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Sample records for syringe calibration factors

  1. Syringe sociology.

    PubMed

    Vitellone, Nicole

    2015-06-01

    In this article I consider the impact of social epistemologies for understanding the object of the syringe. My aim is to examine the process through which the syringe transforms from an injecting device to a tool of social and political inquiry. Paying particular attention to the uses of Foucault, Becker, Bourdieu, Freud and Latour in empirical studies of injecting heroin use, I examine the sociology of the syringe through the lens of habit and habitus, discourse and deviance, mourning and melancholia, attachment and agencement. In pursuing the theory behind the object my goal is to address a sociological object in the making. In so doing I show how the syringe has been significant for social research, social theory, and sociology. It is the difference the object makes that this article seeks to describe. In tracing the epistemology of the syringe I show how the object is important not just for knowledge of addiction but sociology itself. PMID:26072683

  2. High Precision Image Sensor Scale Factor Calibration

    E-print Network

    Hornsey, Richard

    High Precision Image Sensor Scale Factor Calibration Edward Shen, Henok Mebrahtu, Wei Gao, Anthony through the determination of normalized magnification and scale factor. For example, a commercial are the important measurements, only the diagonal elements (u, v), also known as the "scale factors", of the camera

  3. 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

  4. 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 ...

  5. 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. PMID:25829729

  6. Syringe injectable electronics

    PubMed Central

    Hong, Guosong; Zhou, Tao; Jin, Lihua; Duvvuri, Madhavi; Jiang, Zhe; Kruskal, Peter; Xie, Chong; Suo, Zhigang; Fang, Ying; Lieber, Charles M.

    2015-01-01

    Seamless and minimally-invasive three-dimensional (3D) interpenetration of electronics within artificial or natural structures could allow for continuous monitoring and manipulation of their properties. Flexible electronics provide a means for conforming electronics to non-planar surfaces, yet targeted delivery of flexible electronics to internal regions remains difficult. Here, we overcome this challenge by demonstrating syringe injection and subsequent unfolding of submicrometer-thick, centimeter-scale macroporous mesh electronics through needles with a diameter as small as 100 micrometers. Our results show that electronic components can be injected into man-made and biological cavities, as well as dense gels and tissue, with > 90% device yield. We demonstrate several applications of syringe injectable electronics as a general approach for interpenetrating flexible electronics with 3D structures, including (i) monitoring of internal mechanical strains in polymer cavities, (ii) tight integration and low chronic immunoreactivity with several distinct regions of the brain, and (iii) in vivo multiplexed neural recording. Moreover, syringe injection enables delivery of flexible electronics through a rigid shell, delivery of large volume flexible electronics that can fill internal cavities and co-injection of electronics with other materials into host structures, opening up unique applications for flexible electronics. PMID:26053995

  7. Syringe-injectable electronics

    NASA Astrophysics Data System (ADS)

    Liu, Jia; Fu, Tian-Ming; Cheng, Zengguang; Hong, Guosong; Zhou, Tao; Jin, Lihua; Duvvuri, Madhavi; Jiang, Zhe; Kruskal, Peter; Xie, Chong; Suo, Zhigang; Fang, Ying; Lieber, Charles M.

    2015-07-01

    Seamless and minimally invasive three-dimensional interpenetration of electronics within artificial or natural structures could allow for continuous monitoring and manipulation of their properties. Flexible electronics provide a means for conforming electronics to non-planar surfaces, yet targeted delivery of flexible electronics to internal regions remains difficult. Here, we overcome this challenge by demonstrating the syringe injection (and subsequent unfolding) of sub-micrometre-thick, centimetre-scale macroporous mesh electronics through needles with a diameter as small as 100??m. Our results show that electronic components can be injected into man-made and biological cavities, as well as dense gels and tissue, with >90% device yield. We demonstrate several applications of syringe-injectable electronics as a general approach for interpenetrating flexible electronics with three-dimensional structures, including (1) monitoring internal mechanical strains in polymer cavities, (2) tight integration and low chronic immunoreactivity with several distinct regions of the brain, and (3) in vivo multiplexed neural recording. Moreover, syringe injection enables the delivery of flexible electronics through a rigid shell, the delivery of large-volume flexible electronics that can fill internal cavities, and co-injection of electronics with other materials into host structures, opening up unique applications for flexible electronics.

  8. Auto-disable syringes for immunization: issues in technology transfer.

    PubMed Central

    Lloyd, J. S.; Milstien, J. B.

    1999-01-01

    WHO and its partners recommend the use of auto-disable syringes, "bundled" with the supply of vaccines when donor dollars are used, in all mass immunization campaigns, and also strongly advocate their use in routine immunization programmes. Because of the relatively high price of auto-disable syringes, WHO's Technical Network for Logistics in Health recommends that activities be initiated to encourage the transfer of production technology for these syringes as a means of promoting their use and enhancing access to the technology. The present article examines factors influencing technology transfer, including feasibility, corporate interest, cost, quality assurance, intellectual property considerations, and probable time frames for implementation. Technology transfer activities are likely to be complex and difficult, and may not result in lower prices for syringes. Guidelines are offered on technology transfer initiatives for auto-disable syringes to ensure the quality of the product, the reliability of the supply, and the feasibility of the technology transfer activity itself. PMID:10680248

  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. 21 CFR 880.6960 - Irrigating syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Irrigating syringe. 880.6960 Section 880.6960 Food... § 880.6960 Irrigating 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....

  12. 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)

  13. Barriers to Pharmacy-Based Syringe Purchase Among Injection Drug Users in Tijuana, Mexico: A Mixed Methods Study

    PubMed Central

    Lozada, Remedios; Gallardo, Manuel; Rosen, Perth; Vera, Alicia; Macias, Armando; Palinkas, Lawrence A.; Strathdee, Steffanie A.

    2010-01-01

    Injection drug users (IDUs) may be denied purchase of sterile syringes even where purchase without a prescription is legal. This study examined barriers to over-the-counter (OTC) syringe purchase among IDUs in Tijuana, Mexico. A quantitative survey and subsequent focus groups were used to quantify barriers to purchase, identify their correlates and provide in-depth exploration of syringe purchase experiences. Of 627 IDUs, 81% purchased a syringe in the past 6 months and 16% were refused or overcharged. Factors independently associated with refusal/overcharging were homelessness, receptive syringe sharing, >5 uses per syringe, and number of lifetime abscesses. Few pharmacies sold syringes to IDUs, who adapted by limiting purchase attempts to pharmacies known to sell syringes consistently. Failed purchases occurred when drug withdrawal required purchase at unusual times or locations, often following release from jail. IDUs reported syringe sharing, syringe reuse, and searching through unsecured medical waste for syringes in response to failed purchase attempts. Interventions to expand OTC syringe sales to IDUs, particularly near detention facilities, will facilitate safer injection practices. PMID:20300820

  14. Chemistry and the 10cc Syringe

    ERIC Educational Resources Information Center

    Tatton, Hyrum W.

    1973-01-01

    The use of 10cc. syringes in high school chemistry experiments can reduce the expense of equipment and lead to imaginative experimental designs. Describes the equipment and experimental procedures for four experiments utilizing syringes. (JR)

  15. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... syringe is a device intended to inject anesthetic agents subcutaneously or intramuscularly. The device... cartridge) containing anesthetic is placed. After attaching a needle to the syringe body and activating...

  16. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... syringe is a device intended to inject anesthetic agents subcutaneously or intramuscularly. The device... cartridge) containing anesthetic is placed. After attaching a needle to the syringe body and activating...

  17. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... syringe is a device intended to inject anesthetic agents subcutaneously or intramuscularly. The device... cartridge) containing anesthetic is placed. After attaching a needle to the syringe body and activating...

  18. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... syringe is a device intended to inject anesthetic agents subcutaneously or intramuscularly. The device... cartridge) containing anesthetic is placed. After attaching a needle to the syringe body and activating...

  19. 21 CFR 872.6770 - Cartridge syringe.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... syringe is a device intended to inject anesthetic agents subcutaneously or intramuscularly. The device... cartridge) containing anesthetic is placed. After attaching a needle to the syringe body and activating...

  20. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Piston syringe. 880.5860 Section 880.5860 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... Piston syringe. (a) Identification. A piston syringe is a device intended for medical purposes...

  1. 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)

  2. 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.

  3. The coated antiseptic tip (CAT) syringe.

    PubMed

    Mariyaselvam, Maryanne; Hodges, Emily; Richardson, James; Steel, Alistair; Moondi, Parvez; Young, Peter

    2015-01-01

    Catheter-related blood stream infections (CR-BSI) account for 30% of healthcare acquired infection (HAI). Colonization of connector hubs and contaminated syringes are thought to increase the risk of CR-BSI. The Coated Antiseptic Tip (CAT) syringe was developed to decontaminate connector hubs, thereby reducing the risk of CR-BSI. Needleless valves (n?=?20) and three-way connectors (n?=?20) were contaminated with common critical care pathogens. At hourly intervals, CAT syringes were inserted into the connector hubs and normal saline was injected through the connector. This was repeated with control (non-coated) syringes. The internal surface of the connector hubs were swabbed at t?=?0, t?=?1?h and t?=?4?h, inoculated onto blood agar plates and analysed by a blinded microbiologist. Growth was counted as the number of colony forming units. Baseline swabbing demonstrated 100% bacterial hub colonization in both connectors. The CAT syringe showed a significant reduction in CFU growth at 0 and 1?h compared with control syringes (p?syringe completely eliminated bacterial growth in both of the connector hubs. The CAT syringe can effectively disinfect both three-way and needleless connectors. PMID:25970696

  4. 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.

  5. Investigation of factors affecting the calibration of strain gage based transducers ( Goodzeit gages'') for SSC magnets

    SciTech Connect

    Davidson, M.; Gilbertson, A.; Dougherty, M.

    1991-03-01

    These transducers are designed to measure stresses on SSC collared coils. They are individually calibrated with a bonded ten-stack of SSC inner coil cable by applying a known load and reading corresponding output from the gages. The transducer is supported by a notched backing plate'' that allows for bending of the gage beam during calibration or in use with an actual coil. Several factors affecting the calibration and use of the transducers are: the number of times a backing plate'' is used, the similarities or difficulties between bonded ten-stacks, and the differences between the ten-stacks and the coil they represent. The latter is probably the most important because a calibration curve is a model of how a transducer should react within a coil. If the model is wrong, the calibration curve is wrong. Information will be presented regarding differences in calibrations between Brookhaven National Labs (also calibrating these transducers) and Fermilab -- what caused these differences, the investigation into the differences between coils and ten-stacks and how they relate to transducer calibration, and some suggestions for future calibrations.

  6. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Angiographic injector and syringe. 870.1650... injector and syringe. (a) Identification. An angiographic injector and syringe is a device that consists of a syringe and a high-pressure injector which are used to inject contrast material into the...

  7. 10 CFR 35.69 - Labeling of vials and syringes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Labeling of vials and syringes. Each syringe and vial that contains unsealed byproduct material must be labeled to identify the radioactive drug. Each syringe shield and vial shield must also be labeled unless the label on the syringe or vial is visible when shielded....

  8. 21 CFR 880.6960 - Irrigating syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...bulb or a piston syringe with an integral or a detachable tube. The device is used to irrigate, withdraw fluid from, or instill fluid into, a body cavity or wound. (b) Classification. Class I (general controls). The device is...

  9. 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.

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

    PubMed

    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. PMID:25592130

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

    SciTech Connect

    Haseler, Luke J.; Sibbitt, Randy R.; Sibbitt, Wilmer L.; Michael, Adrian A.; Gasparovic, Charles M.; Bankhurst, Arthur D.

    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.

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

    SciTech Connect

    Ashley, J.C.; Turner, J.E.; McMahan, K.L.; Souleyrette, M.L.; Bogard, R.S.

    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.

  13. 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.

  14. Friction condition is an important factor in the control of compressing process. Friction calibration map (FCM), which is also called friction calibration curves (FCCs), is widely used in detecting friction factors

    E-print Network

    Friction condition is an important factor in the control of compressing process. Friction calibration map (FCM), which is also called friction calibration curves (FCCs), is widely used in detecting friction factors between workpiece and die in compression process. The FCM is generated by compressing

  15. 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)

  16. 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)

  17. 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

  18. Open-source syringe pump library.

    PubMed

    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

  19. 21 CFR 870.1670 - Syringe actuator for an injector.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Syringe actuator for an injector. 870.1670 Section... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1670 Syringe actuator for an injector. (a) Identification. A syringe actuator for an injector is an electrical...

  20. 21 CFR 880.6920 - Syringe needle introducer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Syringe needle introducer. 880.6920 Section 880.6920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Devices § 880.6920 Syringe needle introducer. (a) Identification. A syringe needle introducer is a...

  1. Development of Syringe/Bottle Hybrids for Sampling Slurries

    SciTech Connect

    Coleman, C.J.

    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.

  2. Determination of the calibration factor of polysulphone film UV dosemeters for terrestrial solar radiation.

    PubMed

    Krins, A; Dörschel, B; Knuschke, P; Seidlitz, H K; Thiel, S

    2001-01-01

    Polysulphone film is used as a personal UV dosemeter in dermatological or epidemiological studies. The relative efficiency of this detector does not exactly match the action spectrum as proposed by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and to which the UV dose and exposure limits refer. Therefore, the calibration of the dosemeter depends on the spetrum. In the present paper the variation of the calibration factor for terrestrial solar UV spectra is analysed on the basis of a two year observation period at a site near Munich. Germany. A detailed error estimation is included. It is shown that the variation of the calibration factor within this class of spectra is the main contribution to the total uncertainty of the dose determination, which can be up to 40%. The shape of the spectrum of terrestrial solar UV radiation is mainly determined by the total ozone column and the solar elevation angle. It is shown how the calibration depends on these two parameters and how this additional information can help to reduce the measurement error to a residual uncertainty of 17%. Exposure studies of terrestrial solar UV radiation using polysulphone film as a dosemeter would gain in accuracy if total ozone column values at the study's site could be measured or taken from satellite or weather service data. The interpretation of the magnitude of the dose uncertainty depends on the further use of these data. PMID:11707033

  3. 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.

  4. 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…

  5. 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

  6. Note: Calibration of atomic force microscope cantilevers using only their resonant frequency and quality factor

    SciTech Connect

    Sader, John E.; Friend, James R.

    2014-11-15

    A simplified method for calibrating atomic force microscope cantilevers was recently proposed by Sader et al. [Rev. Sci. Instrum. 83, 103705 (2012); Sec. III D] that relies solely on the resonant frequency and quality factor of the cantilever in fluid (typically air). This method eliminates the need to measure the hydrodynamic function of the cantilever, which can be time consuming given the wide range of cantilevers now available. Using laser Doppler vibrometry, we rigorously assess the accuracy of this method for a series of commercially available cantilevers and explore its performance under non-ideal conditions. This shows that the simplified method is highly accurate and can be easily implemented to perform fast, robust, and non-invasive spring constant calibration.

  7. Wrap spring clutch syringe ram and frit mixer

    DOEpatents

    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.

  8. Liquid drugs and high dead space syringes may keep HIV and HCV prevalence high - a comparison of Hungary and Lithuania.

    PubMed

    Gyarmathy, V Anna; Neaigus, Alan; Li, Nan; Ujhelyi, Eszter; Caplinskiene, Irma; Caplinskas, Saulius; Latkin, Carl A

    2010-01-01

    Despitevery similar political, drug policy and HIV prevention backgrounds, HIV and HCV prevalence is considerably different in Hungary (low HIV and moderate HCV prevalence) and Lithuania (high HCV and moderate HIV prevalence). Wecompared the drug use profile of Hungarian (n = 215) and Lithuanian (n = 300) injecting drug users (IDUs). Overall, compared with IDUs in Hungary, IDUs in Lithuania often injected opiates purchased in liquid form ('shirka'), used and shared 2-piece syringes (vs. 1-piece syringes) disproportionately more often, were less likely to acquire their syringes from legal sources and had significantly more experience with injected and less experience with non-injected drugs. It may not be liquid drugs per se that contribute to a higher prevalence of HCV and/or HIV, but it is probably factors associated with the injecting of liquid drugs, such as the wide-spread use and sharing of potentially contaminated 2-piece syringes acquired often from non-legal sources, and syringe-mediated drug sharing with 2-piece syringes. Scaling up substitution therapy, especially heroin replacement, combined with reducing the supply of liquid drugs may decrease the prevalence of high-risk injecting behaviours related to the injecting of liquid drugs and drug injecting-related infections among IDUs in Lithuania. PMID:20798543

  9. 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.

  10. 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

  11. 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.

  12. Syringe Disposal among Injection Drug Users in Harlem and the Bronx during the New York State Expanded Syringe Access Demonstration Program

    ERIC Educational Resources Information Center

    Cleland, Charles M.; Deren, Sherry; Fuller, Crystal M.; Blaney, Shannon; McMahon, James M.; Tortu, Stephanie; Des Jarlais, Don C.; Vlahov, David

    2007-01-01

    Effective January 1, 2001, New York State enacted the Expanded Syringe Access Demonstration Program (ESAP), allowing syringes to be sold in pharmacies without a prescription or dispensed through doctors, hospitals, and clinics to adults. A concern in the assessment of ESAP is its effects on syringe disposal practices. Syringe use data regarding…

  13. 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. PMID:25852577

  14. Solute-Filled Syringe For Formulating Intravenous Solution

    NASA Technical Reports Server (NTRS)

    Owens, Jim; Bindokas, AL; Dudar, Tom; Finley, Mike; Scharf, Mike

    1993-01-01

    Prefilled syringe contains premeasured amount of solute in powder or concentrate form used to deliver solute to sterile interior of large-volume parenteral (LVP) bag. Predetermined amount of sterile water also added to LVP bag through sterilizing filter, and mixed with contents of syringe, yielding sterile intravenous solution of specified concentration.

  15. [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

  16. Calibration of relative sensitivity factors for impact ionization detectors with high-velocity silicate microparticles

    NASA Astrophysics Data System (ADS)

    Fiege, Katherina; Trieloff, Mario; Hillier, Jon K.; Guglielmino, Massimo; Postberg, Frank; Srama, Ralf; Kempf, Sascha; Blum, Jürgen

    2014-10-01

    Impact ionization mass spectrometers, e.g., the Cosmic Dust Analyzer (CDA) onboard the Cassini spacecraft can quantitatively analyze the chemical composition of impacting particles, if the ionization efficiencies of the elements to be quantified are appropriately calibrated. Although silicates are an abundant dust species inside and outside the Solar System, an experimental calibration was not available for elements typically found in silicates. We performed such a calibration by accelerating orthopyroxene dust of known composition with a modified Van de Graaff accelerator to velocities of up to 37.9 km s-1 and subsequent analyses by a high resolution impact ionization mass spectrometer, the Large Area Mass Analyzer (LAMA). The orthopyroxene dust, prepared from a natural rock sample, contains ?90% orthopyroxene and ?10% additional mineral species, such as clinopyroxene, spinel, amphibole, olivine and glasses, which are present as impurities within the orthopyroxene, due to inclusion or intergrowth. Hence, the dust material can be regarded as a multi-mineral mixture. After analyses, we find that most particle data cluster at a composition ascribed to pure orthopyroxene. Some data scatter is caused by stochastic effects, other data scatter is caused by the chemically different mineral impurities. Our data indicate that these minor mineral phases can be recognized within a multi-mineral mixture. Here, for the first time, we present experimentally derived relative sensitivity factors (RSFs) for impact ionization mass spectroscopy of silicates, enabling the quantitative determination of the composition of cosmic dust grains. Orthopyroxene data were used to infer RSFs for Na, Mg, Al, Si, Ca, Ti, Fe and K, for particles with radii ranging from 0.04 ?m to 0.2 ?m and velocities between 19 and 37.9 km s-1, impacting on a Rh-target.

  17. Calibration of a neutron polarimeter to measure the electric form factor of the neutron

    SciTech Connect

    Niculescu, I.; Madey, R.; Suleiman, R.

    1998-02-01

    The authors measured the analyzing power and the efficiency of a new neutron polarimeter that was designed to measure G{sub E}{sup n}, the neutron electric form factor. The polarimeter calibration was performed as experiment E377 at the Indiana University Cyclotron Facility (IUCF) with the {sup 14}C({rvec p}. {rvec n}){sup 14}N reaction at proton beam energies of 124.0, 164.6, and 199.7 MeV without any shielding material ahead of the polarimeter; in addition, at 164.6 MeV the authors measured the analyzing power with 10 cm of lead, sandwiched between 3.5-cm iron plates, ahead of the polarimeter.

  18. 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.

  19. 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

  20. Microbial contamination potential of sterile disposable plastic syringes.

    PubMed

    Huey, W Y; Newton, D W; Augustine, S C; Vejraska, B D; Mitrano, F P

    1985-01-01

    The contamination potential of sterile disposable plastic syringes was evaluated after subjecting the syringes to both simulated in-use conditions and an intentional microbial challenge. Lots of 20 Luer-lock syringes in 10 or 12-cu cm and 20- or 30-cu cm sizes from three manufacturers were tested. Sampling was conducted using 30-ml vials of sterile aerobic culture media containing 14C-labeled substrates. Microbial contamination was confirmed by both visual observation of the turbidity caused by colonization and instrumental detection of 14CO2 caused by the microbial metabolism of 14C-substrates. No contamination of 120 samples was found after the ribbed plunger shaft was grasped by a bare, unprepared dry hand during five cycles of filling and injecting the medium into the vials without removing the needles from the stoppers. When this sampling technique was applied to the syringes inoculated on the upper piston surface with Bacillus subtilis suspension, a 100% contamination rate was observed in 120 samples each under both positive and negative in-vial pressure. Grasping the ribbed plunger shaft of disposable plastic syringes with a dry bare hand did not compromise the sterility of the syringe contents in this study; however, this practice should be avoided when possible. Personnel should absolutely avoid introducing fluid-borne microbial contaminants into the distal barrel end of these syringes because the contents are readily labile to contamination under these conditions. PMID:3918439

  1. Recoil in vacuum for Te ions: Calibration, models, and applications to radioactive-beam g-factor measurements

    SciTech Connect

    Stuchbery, A. E.; Stone, N. J.

    2007-09-15

    In the light of new g factor results for the stable isotopes between {sup 122}Te and {sup 130}Te, the calibration and modeling of the recoil-in-vacuum (RIV) interaction for Te ions is reexamined, and the recent radioactive-beam g factor measurement on {sup 132}Te by the RIV technique is reevaluated. The implications for further RIV g-factor measurements in the {sup 132}Sn region are discussed.

  2. 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

  3. 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...

  4. 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...

  5. 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...

  6. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...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...

  7. 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...

  8. Developing biotechnology company's future positioning strategy in prefilled syringe market

    E-print Network

    Lee, Joonhaeng, S.M. Massachusetts Institute of Technology

    2010-01-01

    The primary goal for the thesis is to develop a recommendation for Amgen's future prefilled syringe strategy related to its drug process development, supplier relationship management plan, supply and sourcing, and procurement. ...

  9. 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

  10. Automatic In-Syringe Dispersive Microsolid Phase Extraction Using Magnetic Metal-Organic Frameworks.

    PubMed

    Maya, Fernando; Palomino Cabello, Carlos; Estela, Jose Manuel; Cerdà, Víctor; Turnes Palomino, Gemma

    2015-08-01

    A novel automatic strategy for the use of micro- and nanomaterials as sorbents for dispersive microsolid phase extraction (D-?-SPE) based on the lab-in-syringe concept is reported. Using the developed technique, the implementation of magnetic metal-organic framework (MOF) materials for automatic solid-phase extraction has been achieved for the first time. A hybrid material based on submicrometric MOF crystals containing Fe3O4 nanoparticles was prepared and retained in the surface of a miniature magnetic bar. The magnetic bar was placed inside the syringe of an automatic bidirectional syringe pump, enabling dispersion and subsequent magnetic retrieval of the MOF hybrid material by automatic activation/deactivation of magnetic stirring. Using malachite green (MG) as a model adsorption analyte, a limit of detection of 0.012 mg/L and a linear working range of 0.04-2 mg/L were obtained for a sample volume equal to the syringe volume (5 mL). MG preconcentration was linear up to a volume of 40 mL, obtaining an enrichment factor of 120. The analysis throughput is 18 h(-1), and up to 3000 extractions/g of material can be performed. Recoveries ranging between 95 and 107% were obtained for the analysis of MG in different types of water and trout fish samples. The developed automatic D-?-SPE technique is a safe alternative for the use of small-sized materials for sample preparation and is readily implementable to other magnetic materials independent of their size and shape and can be easily hyphenated to the majority of detectors and separation techniques. PMID:26138320

  11. Pharmacy Participation in Non-Prescription Syringe Sales in Los Angeles and San Francisco Counties, 2007

    PubMed Central

    Cooper, Erin N.; Dodson, Chaka; Stopka, Thomas J.; Riley, Elise D.; Garfein, Richard S.

    2010-01-01

    Increasing sterile syringe access for injection drug users (IDUs) is one way to prevent HIV and hepatitis C virus (HCV) transmission in this population. In 2005, California Senate Bill 1159 allowed counties to adopt the Disease Prevention Demonstration Project (DPDP). Where enacted, the DPDP allows pharmacies that register with the county to sell up to ten syringes to adults without a prescription. In the current study, we describe pharmacy participation in nonprescription syringe sales (NPSS) in two counties in California and examine factors associated with NPSS. Telephone and in-person interviews were conducted in Los Angeles (LA) and San Francisco (SF) with 238 pharmacies in 2007 (n = 67 in SF; n = 171 in LA). Quantitative survey items captured pharmacy registration with the county, pharmacy policies/practices, episodes and conditions of NPSS and refusals to sell, potential negative consequences of NPSS, and staff attitudes regarding HIV and HCV prevention for IDUs. Overall, 42% of pharmacies reported NPSS (28% in LA and 81% in SF), although only 34% had registered with the county (17% in LA and 76% in SF). Many pharmacies required proof of a medical condition (80% in LA and 30% in SF) and refused NPSS if the customer was a suspected IDU (74% in LA, 33% in SF). Few negative consequences of NPSS were reported. In multivariate logistic regression analysis, we found that the odds of NPSS were significantly higher among pharmacists who thought syringe access was important for preventing HIV among IDUs [adjusted odds ratio (AOR) = 2.95; 95% confidence interval (CI) = 1.10–7.92], were chain pharmacies (AOR = 12.5; 95% CI = 4.55–33.33), and were located in SF (AOR = 4.88; 95% CI = 1.94–12.28). These results suggest that NPSS were influenced by pharmacists’ perception. NPSS might be increased through greater educational efforts directed at pharmacists, particularly those in non-chain pharmacies. PMID:20549568

  12. Attitudes of North Carolina law enforcement officers toward syringe decriminalization

    PubMed Central

    Davis, Corey S.; Johnston, Jill; Zerden, Lisa de Saxe; Clark, Katie; Castillo, Tessie; Childs, Robert

    2015-01-01

    Background North Carolina, like much of the U.S. South, is disproportionately affected by HIV and hepatitis. This persistently high disease burden may be driven in part by laws that criminalize the possession and distribution of syringes for illicit drug use. Legal change to decriminalize syringes may reduce infection rates in the state, but is unlikely absent support from law enforcement actors. Methods We analyzed the responses of 350 North Carolina law enforcement officers to a confidential, anonymous survey. The survey instrument collected data regarding self-reported needle-stick injury (NSI), blood borne disease risk perception and attitudes toward syringe decriminalization. Results 82% of respondents reported that contracting HIV was a “big concern” for them. 3.8% of respondents reported ever receiving a job-related NSI, a rate of 36 NSI per 10,000 officer-years. Majorities of respondents reported positive views regarding syringe decriminalization, with approximately 63% agreeing that it would be “good for the community” and 60% agreeing that it would be “good for law enforcement.” Black and female officers were significantly less likely to agree that on-the-job NSI was a “big concern” and significantly more likely to agree that it would be good for law enforcement. Conclusions These findings suggest that many North Carolina LEOs understand the public health benefits of syringe access programs and may be inclined to support syringe decriminalization legislation. Further research is indicated to determine the causes of observed differences in perceptions of bloodborne disease risk and attitudes toward syringe decriminalization by race and sex. PMID:25193720

  13. Spatial Access to Syringe Exchange Programs and Pharmacies Selling Over-the-Counter Syringes as Predictors of Drug Injectors' Use of Sterile Syringes

    PubMed Central

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

    2011-01-01

    Objectives. We examined relationships of spatial access to syringe exchange programs (SEPs) and pharmacies selling over-the-counter (OTC) syringes with New York City drug injectors’ harm reduction practices. Methods. Each year from 1995 to 2006, we measured the percentage of 42 city health districts’ surface area that was within 1 mile of an SEP or OTC pharmacy. We applied hierarchical generalized linear models to investigate relationships between these exposures and the odds that injectors (n = 4003) used a sterile syringe for at least 75% of injections in the past 6 months. Results. A 1-unit increase in the natural log of the percentage of a district's surface area within a mile of an SEP in 1995 was associated with a 26% increase in the odds of injecting with a sterile syringe; a 1-unit increase in this exposure over time increased these odds 23%. A 1-unit increase in the natural log of OTC pharmacy access improved these odds 15%. Conclusions. Greater spatial access to SEPs and OTC pharmacies improved injectors’ capacity to engage in harm reduction practices that reduce HIV and HCV transmission. PMID:21088267

  14. 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

  15. Volumetric Lattice Boltzmann Simulation for Fluid dynamics and Turbulence in Practical Syringes

    NASA Astrophysics Data System (ADS)

    Lima, Everton; Deep, Debanjan; Yu, Huidan (Whitney)

    2012-11-01

    We conduct numerical experiments to study fluid dynamics and turbulence in syringes using volumetric lattice Boltzmann method (VLBM) that is developed for dealing with arbitrary moving boundaries. Several common used medical syringes are used to predict the efficiency and safety of syringes experiencing low flow infusion rates. It is found that smaller size syringes reach a steady flow rate much sooner than larger ones, which are in quantitative agreement with experimental results. The relation between the syringe size and its steady flow rate is revealed. At low flow rates, corner vortices are observed. We explore conditions that lead to turbulent flow aiming to aid safer syringe application in nursing practices.

  16. Hyaluronic acid filler injections with a 31-gauge insulin syringe.

    PubMed

    Lim, Adrian C

    2010-02-01

    Hyaluronic acid gel is a commonly used skin/soft tissue filler in cosmetic dermatology. Hyaluronic acid fillers are packaged in proprietary luer-lock syringes that can be injected via a 30-gauge, 27-gauge or larger diameter needle depending on the consistency of the gel. A method of decanting proprietary hyaluronic acid fillers into multiple 31-gauge insulin syringes for injection is described. The use of a 31-gauge insulin syringe for filler injections can potentially enhance the injection process through more accurate product delivery and placement. This has the potential to produce a more balanced and symmetrical outcome for patients. Additional benefits include less injection pain, less bleeding/bruising and higher levels of patient satisfaction. PMID:20148851

  17. 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.

  18. Survival of Hepatitis C Virus in Syringes Is Dependent on the Design of the Syringe-Needle and Dead Space Volume

    PubMed Central

    Binka, Mawuena; Paintsil, Elijah; Patel, Amisha; Lindenbach, Brett D.; Heimer, Robert

    2015-01-01

    Background Many people who inject drugs (PWID) use syringes with detachable needles, which have high dead space (HDS). Contaminated HDS blood may substantially contribute to the transmission of HIV, hepatitis C (HCV), and other blood-borne viruses within this population. Newly designed low dead space (LDS) syringe-needle combinations seek to reduce blood-borne virus transmission among PWID. We evaluated the infectivity of HCV-contaminated residual volumes recovered from two LDS syringe-needle combinations. Methods We tested two different design approaches to reducing the dead space. One added a piston to the plunger; the other reduced the dead space within the needle. The two approaches cannot be combined. Recovery of genotype-2a reporter HCV from LDS syringe-needle combinations was compared to recovery from insulin syringes with fixed needles and standard HDS syringe-needle combinations. Recovery of HCV from syringes was determined immediately following their contamination with HCV-spiked plasma, after storage at 22°C for up to 1 week, or after rinsing with water. Results Insulin syringes with fixed needles had the lowest proportion of HCV-positive syringes before and after storage. HCV recovery after immediate use ranged from 47%±4% HCV-positive 1 mL insulin syringes with 27-gauge ½ inch needles to 98%±1% HCV-positive HDS 2 mL syringes with 23-gauge 1¼ inch detachable needles. LDS combinations yielded recoveries ranging from 65%±5% to 93%±3%. Recovery was lower in combinations containing LDS needles than LDS syringes. After 3 days of storage, as much as 6-fold differences in virus recovery was observed, with HCV recovery being lower in combinations containing LDS needles. Most combinations with detachable needles required multiple rinses to reduce HCV infectivity to undetectable levels whereas a single rinse of insulin syringes was sufficient. Conclusions Our study, the first to assess the infectivity of HCV in residual volumes of LDS syringes and needles available to PWID, demonstrates that LDS syringe-needle combination still has the greater potential for HCV transmission than insulin syringes with fixed needles. Improved LDS designs may be able to further reduce HCV recovery, but based on the designed tested, LDS needles and syringes remain intermediate between fixed-needle syringes and HDS combinations in reducing exposure to HCV. PMID:26536599

  19. 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

  20. Magnet/Syringe Separation Issues V.B. Graves

    E-print Network

    McDonald, Kirk

    1 Magnet/Syringe Separation Issues V.B. Graves 8/12/05 This document is an initial response or separate the cylinders from the magnet. Since the cost of stainless cylinders is prohibitively high indicated that 1m would be a sufficient separation distance, in our subsequent phone conversation we thought

  1. 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…

  2. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Section 870.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... 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....

  3. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Section 870.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... 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....

  4. 21 CFR 870.1650 - Angiographic injector and syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Section 870.1650 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... 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....

  5. Disinfection of Syringes Contaminated With Hepatitis C Virus by Rinsing With Household Products

    PubMed Central

    Binka, Mawuena; Paintsil, Elijah; Patel, Amisha; Lindenbach, Brett D.; Heimer, Robert

    2015-01-01

    Background.?Hepatitis C virus (HCV) transmission among people who inject drugs (PWID) is associated with the sharing of injection paraphernalia. People who inject drugs often “disinfect” used syringes with household products when new syringes are unavailable. We assessed the effectiveness of these products in disinfecting HCV-contaminated syringes. Methods.?A genotype-2a reporter virus assay was used to assess HCV infectivity in syringes postrinsing. Hepatitis C virus-contaminated 1 mL insulin syringes with fixed needles and 1 mL tuberculin syringes with detachable needles were rinsed with water, Clorox bleach, hydrogen peroxide, ethanol, isopropanol, Lysol, or Dawn Ultra at different concentrations. Syringes were either immediately tested for viable virus or stored at 4°C, 22°C, and 37°C for up to 21 days before viral infectivity was determined. Results.?Most products tested reduced HCV infectivity to undetectable levels in insulin syringes. Bleach eliminated HCV infectivity in both syringes. Other disinfectants produced virus recovery ranging from high (5% ethanol, 77% ± 12% HCV-positive syringes) to low (1:800 Dawn Ultra, 7% ± 7% positive syringes) in tuberculin syringes. Conclusions.?Household disinfectants tested were more effective in fixed-needle syringes (low residual volume) than in syringes with detachable needles (high residual volume). Bleach was the most effective disinfectant after 1 rinse, whereas other diluted household products required multiple rinses to eliminate HCV. Rinsing with water, 5% ethanol (as in beer), and 20% ethanol (as in fortified wine) was ineffective and should be avoided. Our data suggest that rinsing of syringes with household disinfectants may be an effective tool in preventing HCV transmission in PWID when done properly. PMID:26034767

  6. SU-E-T-491: Importance of Energy Dependent Protons Per MU Calibration Factors in IMPT Dose Calculations Using Monte Carlo Technique

    SciTech Connect

    Randeniya, S; Mirkovic, D; Titt, U; Guan, F; Mohan, R

    2014-06-01

    Purpose: In intensity modulated proton therapy (IMPT), energy dependent, protons per monitor unit (MU) calibration factors are important parameters that determine absolute dose values from energy deposition data obtained from Monte Carlo (MC) simulations. Purpose of this study was to assess the sensitivity of MC-computed absolute dose distributions to the protons/MU calibration factors in IMPT. Methods: A “verification plan” (i.e., treatment beams applied individually to water phantom) of a head and neck patient plan was calculated using MC technique. The patient plan had three beams; one posterior-anterior (PA); two anterior oblique. Dose prescription was 66 Gy in 30 fractions. Of the total MUs, 58% was delivered in PA beam, 25% and 17% in other two. Energy deposition data obtained from the MC simulation were converted to Gy using energy dependent protons/MU calibrations factors obtained from two methods. First method is based on experimental measurements and MC simulations. Second is based on hand calculations, based on how many ion pairs were produced per proton in the dose monitor and how many ion pairs is equal to 1 MU (vendor recommended method). Dose distributions obtained from method one was compared with those from method two. Results: Average difference of 8% in protons/MU calibration factors between method one and two converted into 27 % difference in absolute dose values for PA beam; although dose distributions preserved the shape of 3D dose distribution qualitatively, they were different quantitatively. For two oblique beams, significant difference in absolute dose was not observed. Conclusion: Results demonstrate that protons/MU calibration factors can have a significant impact on absolute dose values in IMPT depending on the fraction of MUs delivered. When number of MUs increases the effect due to the calibration factors amplify. In determining protons/MU calibration factors, experimental method should be preferred in MC dose calculations. Research supported by National Cancer Institute grant P01CA021239.

  7. Safer ambulatory syringe drivers: experiences of one acute hospital trust.

    PubMed

    Freemantle, Alison; Clark, Daniel; Crosby, Vincent

    2011-02-01

    In December 2010 the National Patient Safety Agency released a Rapid Response Report citing evidence of harm and death necessitating the need to immediately address safety issues affecting ambulatory syringe drivers with rate settings in millimetres of travel. These devices are widely used in palliative care in the UK, both in the community and in the hospital setting. In order to ensure a successful changeover to a safer system, a coordinated, multidisciplinary, cross-boundary approach is essential. This article outlines the experiences of one acute hospital trust in identifying and trialling ambulatory syringe drivers to potentially adopt, and in implementing the selected driver and training staff in its use. It is hoped that it will provide insight into the challenges of undertaking such a change in practice. PMID:21378693

  8. Rheological and syringeability properties of highly concentrated human polyclonal immunoglobulin solutions.

    PubMed

    Burckbuchler, V; Mekhloufi, G; Giteau, A Paillard; Grossiord, J L; Huille, S; Agnely, F

    2010-11-01

    This study of highly concentrated polyvalent immunoglobulin solutions, IgG, aimed at analyzing the relationships between protein concentration and aggregation on the one hand and viscosity on the other hand. Viscosity variations as a function of IgG concentration showed two well-defined behaviours: a Newtonian behaviour for low-concentrated solutions and a shear-thinning behaviour for highly concentrated ones. The viscosity data fitted very well with the Mooney model, suggesting the absence of intermolecular interactions in the IgG solutions that behaved like a non-interacting suspension of hard particles. The polyclonal nature of IgG seems to prevent intermolecular interaction. The shape factor, determined from Mooney fitting, revealed a non-spherical shape of the polyclonal IgG molecules. The rheological properties were also correlated with the injection force (F) through hypodermic needles by syringeability tests. Here, F was mainly affected by three parameters: the solution viscosity, the injection flow rate, and the needle characteristics. In fact, syringeability tests showed that F increased with IgG concentration and flow rate and decreased with the internal diameter of the needle. A zone for optimal injection conditions was then identified taking into account the different affecting parameters and mainly a maximum force for manual injection, which was fixed at 30N. PMID:20719247

  9. 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

  10. 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

  11. [Measurement of peak correction factor of Farmer chamber for calibration of flattening filter free (FFF) clinical photon beams].

    PubMed

    Kontra, Gábor; Major, Tibor; Polgár, Csaba

    2015-06-01

    Farmer-type ionization chambers are considered the most reliable detectors and for this reason they are most frequently used for the calibration of photon beams of medical linear accelerators. Flattening filter free (FFF) photon beams of linear accelerators have recently started to be used in radiotherapy. The dose profile of FFF beams is peaked in the center of the field and the dose distribution will be inhomogeneous along the axis of the 2.3 cm long measuring volume of the Farmer chamber. The peaked radiation field will result in volume averaging effects in the large Farmer chamber, therefore this chamber will underestimate the true central axis dose. Our objective was to determine the value of the peak correction factor (Kp) of Farmer-type chamber with measurements to avoid the underestimation of the central axis dose during the calibration of FFF radiation fields. Measurements were made with 6 MV and 10 MV flattened (6X and 10X) and FFF beams (6XFFF and 10XFFF) of a Varian TrueBeam medical linear accelerator in a solid water phantom at 10 cm depth. The source surface distance (SSD) was 100 cm, the field size was 10×10 cm and the dose rate was always 400 MU/min during the measurements. We delivered 100 MU in each measurement and the absorbed dose to water was calculated according to the IAEA TRS-398 dosimetry protocol. The measured signals of the ionization chambers were always corrected for the ion recombination loss. The ion recombination correction factors (Kr) were determined with the two-voltage method separately for the used ion chambers and for flattened and unflattened beams. First, we measured the dose to water with PTW TM30012 Farmer chamber in 6XFFF and 6X beams, then calculated the ratio of doses of 6XFFF and 6X beams (R6,Farmer). Immediately after this we repeated the above measurements with PTW TM31010 Semiflex chamber and determined the ratio of doses of 6XFFF and 6X beams again (R6,Semiflex). The length of the sensitive volume of the Semiflex chamber is only 6.5 mm. According to our dose profile measurements the peak correction factor of this chamber equals to unity for both photon energies. As a consequence R6,Semiflex is larger than R6,Farmer and Kp6XFFF = R6,Semiflex / R6,Farmer, where Kp6XFFF is the peak correction factor of the Farmer chamber in 6XFFF beam. The advantage of this method is that we have to calculate ratio of doses, so it is not necessary to know the calibration factors of the chambers. Repeating the above measurements with 10X and 10XFFF beams we determined the peak correction factor of Farmer chamber for 10XFFF beam, too (Kp10XFFF). According to our measurements Kp6XFFF = 1.0025 and Kp10XFFF = 1.009. The bigger peak correction factor for 10XFFF beam is in accordance with the fact that the peak of dose profile is steeper for higher photon energy. The above described method for the determination of Kp can be used for other photon energies and other large volume ionization chambers. PMID:26035159

  12. Syringe access for the prevention of blood borne infections among injection drug users

    PubMed Central

    Stancliff, Sharon; Agins, Bruce; Rich, Josiah D; Burris, Scott

    2003-01-01

    Background Approximately one-third of acquired immunodeficiency syndrome cases in the United States are associated with the practice of sharing of injection equipment and are preventable through the once-only use of syringes, needles and other injection equipment. Discussion Sterile syringes may be obtained legally by 4 methods depending on the state. They may be purchased over the counter, prescribed, obtained at syringe exchange programs or furnished by authorized agencies. Each of these avenues has advantages and disadvantages; therefore, legal access through all means is the most likely way to promote the use of sterile syringes. Summary By assisting illicit drug injectors to obtain sterile syringes the primary care provider is able to reduce the incidence of blood borne infections, and educate patients about safe syringe disposal. The provider is also able to initiate discussion about drug use in a nonjudgmental manner and to offer care to patients who are not yet ready to consider drug treatment. PMID:14633286

  13. Calibration procedures for measurement of reflectance factor in remote sensing field research

    NASA Technical Reports Server (NTRS)

    Robinson, B. F.; Biehl, L. L.

    1982-01-01

    A means by which measurements of the optical properties of crops and soils can be knowledgeably compared from site to site and instrument to instrument is presented in detail. The definition of bidirectional reflectance factor is reviewed and discussed. Procedures for field implementation are illustrated and discussed. Spectral and goniometric properties of laboratory and field reference surfaces are given. It is concluded that intelligent use of the bidirectional reflectance factor technique is an accurate and practical means to obtain the spectral, optical properties of crops and soils needed for advancements in agricultural remote sensing.

  14. 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.

  15. Mechanical properties of composites as functions of the syringe storage temperature and energy dose

    PubMed Central

    CHAVES, Fernanda Oliveira; de FARIAS, Natália Coelho; MEDEIROS, Luciano Marcelo de Mello; ALONSO, Roberta Caroline Bruschi; DI HIPÓLITO, Vinicius; D'ALPINO, Paulo Henrique Perlatti

    2015-01-01

    Objective: To investigate the mechanical properties of different classifications of composites indicated for posterior application as functions of the storage condition and of the energy dose. Material and Methods: Specimens (8x2x2 mm) were obtained according to the factors: I) Composites (3M ESPE): Filtek P60, Filtek Z350XT, and Filtek Silorane; II) Syringe storage conditions: room temperature, aged, oven, refrigerator, and freezer; and III) Energy dose: 24 J/cm2 and 48 J/cm2. After photoactivation, the specimens were stored at 37ºC for 24 h. After storage, a three-point bending test was carried out in a universal testing machine at 0.5 mm/min. Flexural strength (S) and flexural modulus (E) were calculated. Data were analyzed by three-way ANOVA and Tukey's test (?=0.05). Results: Different storage conditions significantly affected the silorane composite for S; conversely, no effects were noted in terms of E. The accelerated aging protocol significantly increased the S of Filtek P60 and Filtek Silorane, whereas storage in the oven significantly decreased the S for all of the composites tested. Filtek P60 was the only composite not affected by the lower storage temperatures tested for S, whereas for the silorane this parameter was impacted at the same conditions. The factor "dose" was not statistically significant. Conclusions: The syringe storage at different temperature conditions proved to influence mostly the flexural strength, a clinically important characteristic considering the posterior indication of the materials tested. The silorane composite should not be stored at lower temperatures. PMID:25075673

  16. [Uncertainty of cross calibration-applied beam quality conversion factor for the Japan Society of Medical Physics 12].

    PubMed

    Kinoshita, Naoki; Kita, Akinobu; Takemura, Akihiro; Nishimoto, Yasuhiro; Adachi, Toshiki

    2014-09-01

    The uncertainty of the beam quality conversion factor (k(Q,Q0)) of standard dosimetry of absorbed dose to water in external beam radiotherapy 12 (JSMP12) is determined by combining the uncertainty of each beam quality conversion factor calculated for each type of ionization chamber. However, there is no guarantee that ionization chambers of the same type have the same structure and thickness, so there may be individual variations. We evaluated the uncertainty of k(Q,Q0) for JSMP12 using an ionization chamber dosimeter and linear accelerator without a specific device or technique in consideration of the individual variation of ionization chambers and in clinical radiation field. The cross calibration formula was modified and the beam quality conversion factor for the experimental values [(k(Q,Q0))field] determined using the modified formula. It's uncertainty was calculated to be 1.9%. The differences between (k(Q,Q0))field of experimental values and k(Q,Q0) for Japan Society of Medical Physics 12 (JSMP12) were 0.73% and 0.88% for 6- and 10-MV photon beams, respectively, remaining within ± 1.9%. This showed k(Q,Q0) for JSMP12 to be consistent with (k(Q,Q0))field of experimental values within the estimated uncertainty range. Although inter-individual differences may be generated, even when the same type of ionized chamber is used, k(Q,Q0) for JSMP12 appears to be consistent within the estimated uncertainty range of (k(Q,Q0)field. PMID:25242596

  17. 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…

  18. 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.

  19. Pharmacy access to syringes among injecting drug users: follow-up findings from Hartford, Connecticut.

    PubMed Central

    Singer, M; Baer, H A; Scott, G; Horowitz, S; Weinstein, B

    1998-01-01

    OBJECTIVE: To break the link between drug use and the human immunodeficiency virus (HIV), in 1992 the state of Connecticut rescinded a 14-year ban on pharmacy sales of syringes without a physician's prescription. In 1993, the Center for Disease Control and Prevention (CDC) evaluated the impact of the new legislation on access to syringes among injecting drug users (IDUs) and found an initial pattern of expanded access. However, it also found that some pharmacies, after negative experiences with IDU customers, reverted to requiring a prescription. This chapter reports findings from a four-year follow-up study of current IDU access to over-the-counter (OTC) pharmacy syringes in Hartford, Connecticut. METHODS: Through structured interviews, brief telephone interviews, and mailed surveys, data on nonprescription syringe sale practices were collected on 27 pharmacies, including 18 of the 21 pharmacies in Hartford and none from pharmacies in contiguous towns, during June and July 1997. Interview data on pharmacy syringe purchase from two sample of IDUs, a group of out-of-treatment injectors recruited through street outreach, and a sample of users of the Hartford Needle Exchange Program, also are reported. RESULTS: The study found that, while market trends as well as negative experiences have further limited pharmacy availability of nonprescription syringes, pharmacies remain an important source of sterile syringes for IDUs. However, the distribution of access in not even; in some areas of the city it is much easier to purchase nonprescription syringes than in other. All of the seven pharmacies located on the north end of Hartford reported that they had a policy of selling OTC syringes, whereas only six (54.5%) of the II pharmacies located on the south end have such a policy. Overt racial discrimination was not found to be a barrier to OTC access to syringes. CONCLUSIONS: To further decrease acquired immunodeficiency syndrome (AIDS) risk among IDUs, there is a need for public education to counter empirically unsupported stereotypes about IDUs that diminish their access to health care and AIDS prevention resources and services. In states or cities where pharmacy sale of nonprescription syringes is illegal, policy makers should examine the benefits of removing existing barriers to sterile syringe acquisition. In cases in which pharmacy sale of nonprescription syringes is legal, local health departments should implement educational programs to inform pharmacy staff and management about the critically important role low-cost (or cost-free), sterile syringe access can play in HIV prevention. PMID:9722813

  20. [Abortion at 10 to 12 weeks using a plastic syringe or electric aspirator].

    PubMed

    Borko, E; Breznik, R; Ivanisevi?, V; Kokos, Z

    1983-01-01

    The study included 170 women subjected to menstrual regulation. The double-valve band syringe was used in 96 and the electric pump (the vacuum source usually used at the Department) in 74 cases. Nearly all the procedures were performed under general anesthesia, using 8 mm, 10 mm or 12 mm plastic rigid cannulae. Three abortions with the hand syringe also required dilatation and curettage, and all three women suffered blood loss exceeding 100 ml. There was one cervical laceration surgically repaired and a case of adnexitis reported among the hand syringe group. Immediate complications occurred in 7.3% of the cases using the hand syringe and in 4.1% of using the electric pump. The mean procedural time was 4.2 minutes and 4.0 minutes, respectively, with the hand syringe and the electric pump. Only three women reported complications or complaints at the follow-up visit, all of them from the electric pump group. PMID:6645610

  1. Syringe-pump-induced fluctuation in all-aqueous microfluidic system implications for flow rate accuracy.

    PubMed

    Li, Zida; Mak, Sze Yi; Sauret, Alban; Shum, Ho Cheung

    2014-02-21

    We report a new method to display the minute fluctuations induced by syringe pumps on microfluidic flows by using a liquid-liquid system with an ultralow interfacial tension. We demonstrate that the stepper motor inside the pump is a source of fluctuations in microfluidic flows by comparing the frequencies of the ripples observed at the interface to that of the pulsation of the stepper motor. We also quantify the fluctuations induced at different flow rates, using syringes of different diameters, and using different syringe pumps with different advancing distances per step. Our work provides a way to predict the frequency of the fluctuation that the driving syringe pump induces on a microfluidic system and suggests that syringe pumps can be a source of fluctuations in microfluidic flows, thus contributing to the polydispersity of the resulting droplets. PMID:24382584

  2. Clinical performance and safety of adapters for intradermal delivery with conventional and autodisable syringes.

    PubMed

    Tsals, Izrail; Jarrahian, Courtney; Snyder, Fred E; Saganic, Laura; Saxon, Eugene; Zehrung, Darin; Zimmerman, Glen; Papania, Mark; Klaff, Leslie

    2015-09-01

    Although the number of vaccines and diagnostic tests currently delivered intradermally is limited, this route of administration offers potential advantages due to the high concentration of antigen-presenting cells in the skin. One factor which may in part be limiting development and use of intradermal (ID) administration is concern about the ease and reliability of the needle and syringe-based Mantoux technique. A phase I clinical study was conducted to evaluate two ID adapters that have been developed as injection-delivery aids to increase the safety, simplicity, and reliability of ID injection: a prototype autodisable, intradermal (ADID) adapter for autodisable (AD) syringes, and a marketed side-merge adapter (SMA). Thirty healthy adult volunteers each received six injections of 0.1 mL of sterile saline solution. Each adapter was used to give injections into the upper deltoid, forearm, and suprascapular regions of each volunteer. The needle-bevel orientation during injection was random. Injection performance was determined by measuring wheal size and fluid leakage. Wheals were similar in size for the ADID adapter (mean 9.9 ± 0.17 mm) and SMA (mean 9.8 ± 0.15 mm). In all of the injections completed with the SMA, and 98% of those completed with the ADID, fluid leakage was less than 10% of the intended injection volume. Minor skin abrasions were the only adverse events. Based on self-reporting of pain, injections were well tolerated (mean pain score of 2 on a 0-10 scale). ID delivery using the SMA and ADID adapters appears safe and effective. PMID:25964169

  3. 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

    ...; Glass Syringes for Delivering Drug and Biological Products: Technical Information To Supplement... availability of draft guidance for industry and FDA staff entitled ``Glass Syringes for Delivering Drug and... glass syringes that comply with the ISO 11040-4 standard when connected to devices (``connecting...

  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

    ...and Food and Drug Administration Staff; Glass Syringes for Delivering Drug and Biological...for industry and FDA staff entitled ``Glass Syringes for Delivering Drug and Biological...to ensure the safe and effective use of glass syringes that comply with the ISO...

  5. 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.

  6. 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

  7. Selecting the correct weighting factors for linear and quadratic calibration curves with least-squares regression algorithm in bioanalytical LC-MS/MS assays and impacts of using incorrect weighting factors on curve stability, data quality, and assay performance.

    PubMed

    Gu, Huidong; Liu, Guowen; Wang, Jian; Aubry, Anne-Françoise; Arnold, Mark E

    2014-09-16

    A simple procedure for selecting the correct weighting factors for linear and quadratic calibration curves with least-squares regression algorithm in bioanalytical LC-MS/MS assays is reported. The correct weighting factor is determined by the relationship between the standard deviation of instrument responses (?) and the concentrations (x). The weighting factor of 1, 1/x, or 1/x(2) should be selected if, over the entire concentration range, ? is a constant, ?(2) is proportional to x, or ? is proportional to x, respectively. For the first time, we demonstrated with detailed scientific reasoning, solid historical data, and convincing justification that 1/x(2) should always be used as the weighting factor for all bioanalytical LC-MS/MS assays. The impacts of using incorrect weighting factors on curve stability, data quality, and assay performance were thoroughly investigated. It was found that the most stable curve could be obtained when the correct weighting factor was used, whereas other curves using incorrect weighting factors were unstable. It was also found that there was a very insignificant impact on the concentrations reported with calibration curves using incorrect weighting factors as the concentrations were always reported with the passing curves which actually overlapped with or were very close to the curves using the correct weighting factor. However, the use of incorrect weighting factors did impact the assay performance significantly. Finally, the difference between the weighting factors of 1/x(2) and 1/y(2) was discussed. All of the findings can be generalized and applied into other quantitative analysis techniques using calibration curves with weighted least-squares regression algorithm. PMID:25157966

  8. 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.

  9. Pharmacy Participation in Non-Prescription Syringe Sales in Los Angeles and San Francisco Counties, 2007

    E-print Network

    Cooper, Erin N.; Dodson, Chaka; Stopka, Thomas J.; Riley, Elise D.; Garfein, Richard S.; Bluthenthal, Ricky N.

    2010-01-01

    legal and policy changes to prevent HIV and hepatitis CHIV, Viral hepatitis, Sterile syringe access, Pharmacy, Policy,policies/ practices, episodes and conditions of NPSS and refusals to sell, potential negative consequences of NPSS, and staff attitudes regarding HIV and

  10. Optimization of labor allocation at a syringe production facility : design proposals

    E-print Network

    Su, Xiangyong

    2008-01-01

    At MD Medical (Singapore), the syringe value stream is facing escalating labor cost and high labor turnover. Therefore, optimization of the current labor resources is necessary to control the labor cost effectively without ...

  11. In vivo evaluation of a microneedle-based miniature syringe for intradermal drug delivery.

    PubMed

    Häfeli, Urs O; Mokhtari, Amir; Liepmann, Dorian; Stoeber, Boris

    2009-10-01

    A microfabrication process for miniature syringes is described. The MEMS syringes consist of a silicon plate with an array of hollow out-of-plane needles and a flexible poly-dimethylsiloxane (PDMS) reservoir attached to the back of the plate. The PDMS reservoir can be filled with a drug solution or microparticle suspension which is delivered into the skin simply by the pressure of a finger pushing on the miniature syringe. The efficiency of such a syringe for delivering a suspension of microparticles into skin tissue and a radiolabelled protein (albumin) solution into live mice is reported. Such microneedle devices could be used for the intradermal delivery of vaccination agents or for the systemic delivery of highly effective drugs. PMID:19347587

  12. SAR calibration technology review

    NASA Technical Reports Server (NTRS)

    Walker, J. L.; Larson, R. W.

    1981-01-01

    Synthetic Aperture Radar (SAR) calibration technology including a general description of the primary calibration techniques and some of the factors which affect the performance of calibrated SAR systems are reviewed. The use of reference reflectors for measurement of the total system transfer function along with an on-board calibration signal generator for monitoring the temporal variations of the receiver to processor output is a practical approach for SAR calibration. However, preliminary error analysis and previous experimental measurements indicate that reflectivity measurement accuracies of better than 3 dB will be difficult to achieve. This is not adequate for many applications and, therefore, improved end-to-end SAR calibration techniques are required.

  13. Syringe Exchange in the United States: A National Level Economic Evaluation of Hypothetical Increases in Investment

    PubMed Central

    Weir, Brian W.; Des Jarlais, Don C.; Pinkerton, Steven D.; Holtgrave, David R.

    2014-01-01

    To examine whether increasing investment in needle/syringe exchange programs (NSPs) in the US would be cost-effective for HIV prevention, we modeled HIV incidence in hypothetical cases with higher NSP syringe supply than current levels, and estimated number of infections averted, cost per infection averted, treatment costs saved, and financial return on investment. We modified Pinkerton’s model, which was an adaptation of Kaplan’s simplified needle circulation theory model, to compare different syringe supply levels, account for syringes from non-NSP sources, and reflect reduction in syringe sharing and contamination. With an annual $10 to $50 million funding increase, 194–816 HIV infections would be averted (cost per infection averted $51,601– $61,302). Contrasted with HIV treatment cost savings alone, the rate of financial return on investment would be 7.58–6.38. Main and sensitivity analyses strongly suggest that it would be cost-saving for the US to invest in syringe exchange expansion. PMID:24824043

  14. In-syringe dispersive solid phase extraction: a novel format for electrospun fiber based microextraction.

    PubMed

    Zhu, Gang-Tian; He, Xiao-Mei; Cai, Bao-Dong; Wang, Han; Ding, Jun; Yuan, Bi-Feng; Feng, Yu-Qi

    2014-12-01

    A novel in-syringe dispersive solid phase extraction (dSPE) system using electrospun silica fibers as adsorbents has been developed in the current work. A few milligrams of electrospun silica fibers were incubated in sample solution in the barrel of a syringe for microextraction assisted by vortex. Due to the benefit of dispersion and the high mass transfer rate of the sub-microscale electrospun silica fibers, the extraction equilibrium was achieved in a very short time (less than 1 min). Moreover, thanks to the long fibrous properties of electrospun fibers, the separation of the adsorbent from sample solution was easily achieved by pushing out the sample solution which therefore simplified the sample pretreatment procedure. Besides, the analytical throughput was largely increased by using a multi-syringe plate to perform the extraction experiment. The performance of the in-syringe dSPE device was evaluated by extraction of endogenous cytokinins from plant tissue samples based on the hydrophilic interaction. Six endogenous cytokinins in 20 mg of Oryza sativa L. (O. sativa) leaves were successfully determined under optimized conditions using in-syringe dSPE combined with liquid chromatography-mass spectrometry analysis. The results demonstrated that the in-syringe dSPE method was a rapid and high-throughput strategy for the extraction of target compounds, which has great potential in microscale sample pretreatment using electrospun fibers. PMID:25317894

  15. Using a modified syringe technique to adjust the intracuff pressure of a laryngeal mask airway.

    PubMed

    Hung, Kuo-Chuan; Chen, Wei-Hung; Shih, Yu-Hsuan; Yeh, Li-Ren

    2015-12-01

    Limiting the intracuff pressure of a laryngeal mask airway (LMA) to <60 cmH2O is recommended in clinical practice. This report aimed to assess the efficacy of a modified syringe technique to adjust the intracuff pressure of an LMA. In a preclinical study, commercially available 20-mL syringes were attached to the pilot balloon of LMAs with different preset intracuff pressures (40 cmH2O, 50 cmH2O, 60 cmH2O, 70 cmH2O, 80 cmH2O, 100 cmH2O, and 120 cmH2O). After attachment, the syringe plunger was allowed to passively rebound. If no rebound of the plunger was observed after attachment, 1 mL of air was withdrawn and the plunger was allowed to passively rebound again. This technique allowed the plunger to overcome static friction and avoid excessive deflation of the LMA cuffs. The intracuff pressure was measured using a manometer after the plunger ceased moving. In the preclinical study, the intracuff pressure was always less than or close to 60 cmH2O after adjustment using this modified syringe technique. After evaluating the performance and characteristics of the syringe in the preclinical study, we concluded that the modified syringe technique may be useful for adjusting LMA intracuff pressure effectively. PMID:25962713

  16. Syringe exchange in the United States: a national level economic evaluation of hypothetical increases in investment.

    PubMed

    Nguyen, Trang Quynh; Weir, Brian W; Des Jarlais, Don C; Pinkerton, Steven D; Holtgrave, David R

    2014-11-01

    To examine whether increasing investment in needle/syringe exchange programs (NSPs) in the US would be cost-effective for HIV prevention, we modeled HIV incidence in hypothetical cases with higher NSP syringe supply than current levels, and estimated number of infections averted, cost per infection averted, treatment costs saved, and financial return on investment. We modified Pinkerton's model, which was an adaptation of Kaplan's simplified needle circulation theory model, to compare different syringe supply levels, account for syringes from non-NSP sources, and reflect reduction in syringe sharing and contamination. With an annual $10 to $50 million funding increase, 194-816 HIV infections would be averted (cost per infection averted $51,601-$61,302). Contrasted with HIV treatment cost savings alone, the rate of financial return on investment would be 7.58-6.38. Main and sensitivity analyses strongly suggest that it would be cost-saving for the US to invest in syringe exchange expansion. PMID:24824043

  17. SU-E-T-298: Small Field Total Scatter Factors Using a Commercial Scintillator Detector: Calibration Parameters Are Not Independent of Field Size

    SciTech Connect

    Jornet, N; Carrasco de Fez, P; Jordi, O; Latorre-Musoll, A; Eudaldo, T; Ruiz-Martinez, A; Ribas Morales, M

    2014-06-01

    Purpose: To evaluate the accuracy in total scatter factor (Sc,p) determination for small fields using commercial plastic scintillator detector (PSD). The manufacturer's spectral discrimination method to subtract Cerenkov light from the signal is discussed. Methods: Sc,p for field sizes ranging from 0.5 to 10 cm were measured using PSD Exradin (Standard Imaging) connected to two channel electrometer measuring the signals in two different spectral regions to subtract the Cerenkov signal from the PSD signal. A Pinpoint ionisation chamber 31006 (PTW) and a non-shielded semiconductor detector EFD (Scanditronix) were used for comparison. Measures were performed for a 6 MV X-ray beam. The Sc,p are measured at 10 cm depth in water for a SSD=100 cm and normalized to a 10'10 cm{sup 2} field size at the isocenter. All detectors were placed with their symmetry axis parallel to the beam axis.We followed the manufacturer's recommended calibration methodology to subtract the Cerenkov contribution to the signal as well as a modified method using smaller field sizes. The Sc,p calculated by using both calibration methodologies were compared. Results: Sc,p measured with the semiconductor and the PinPoint detectors agree, within 1.5%, for field sizes between 10'10 and 1'1 cm{sup 2}. Sc,p measured with the PSD using the manufacturer's calibration methodology were systematically 4% higher than those measured with the semiconductor detector for field sizes smaller than 5'5 cm{sup 2}. By using a modified calibration methodology for smalls fields and keeping the manufacturer calibration methodology for fields larger than 5'5cm{sup 2} field Sc,p matched semiconductor results within 2% field sizes larger than 1.5 cm. Conclusion: The calibration methodology proposed by the manufacturer is not appropriate for dose measurements in small fields. The calibration parameters are not independent of the incident radiation spectrum for this PSD. This work was partially financed by grant 2012 of Barcelona board of the AECC.

  18. High dead-space syringe use among people who inject drugs in Tijuana, Mexico

    PubMed Central

    Rafful, Claudia; Zule, William; González-Zúñiga, Patricia E.; Werb, Dan; Elena Medina-Mora, María; Magis-Rodriguez, Carlos; Strathdee, Steffanie A.

    2015-01-01

    Background High dead-space syringes (HDSS) are believed to confer an elevated risk of acquiring HIV and other blood-borne infections. Objectives We identified prevalence and correlates of HDSS use among injection drug users (IDU) in Tijuana, Mexico, where syringe purchase and possession is legal without a prescription. Methods Beginning in 2011, IDU who reported being 18 years or older, who injected drugs within the last month were recruited into a prospective study. At baseline and semi-annually, 557 IDU underwent HIV-testing and interviewer-administered surveys. Logistic regression was used to identify correlates of using HDSS. Results Of 557 IDU, 40% had ever used HDSS, mostly because no other syringe type was available (72%), or because they were easier to get (20%). Controlling for sex and age at first injection, use of HDSS was associated with cocaine as the first drug injected (Adjusted Odds Ratio [AOR]:2.68; Confidence Interval 95% [CI]:1.15-6.22), having been stopped or arrested by police (AOR:1.84; 95% CI:1.11-3.07), being deported from the US (AOR:1.64; 95%CI:1.06-2.53), and believing it is illegal to carry syringes (AOR:1.78; 95%CI:1.01-3.15). Conclusion Use of HDSS is surprisingly common among IDU in Tijuana. Efforts are needed to expand coverage of low-dead space syringes through existing syringe exchange programs. Education is required to increase awareness of the harms associated with HDSS, and to inform IDU that syringe possession is legal across Mexico. PMID:25695145

  19. Stability of micafungin sodium solutions at different concentrations in glass bottles and syringes.

    PubMed

    Briot, Thomas; Vrignaud, Sandy; Lagarce, Frédéric

    2015-08-15

    Micafungin is a costly treatment and packaging of 50 mg or 100 mg bottles only are available, while doses lower than 5 mg and 20 mg are often necessary in neonates and paediatrics patients, respectively. The stability of micafungin sodium in polypropylene syringes and glass bottles was studied at different concentrations. Solutions of micafungin diluted with NaCl 0.9% were prepared in glass bottles (20 and 10 mg/mL) or syringes (1 and 0.5 mg/mL) and stored at 25 °C, 60% humidity (RH), in the dark (ICH conditions). Solutions were also exposed to heat (70 °C) or alkaline solution (NaOH) in order to force degradation. Samples were analysed at days 1, 5, 8 (for bottles) and also 15 (for syringes) after the preparation and assayed in triplicate. Stability was studied using a stability-indicating high-performance liquid chromatographic method. Syringes stored at 25 °C retained over 90% of their initial concentration over the study period. Temperature and alkaline conditions had significant effect on the stability of micafungin, leading to apparition of degradation products. Moreover, sub visible particles were in the specification of the European Pharmacopeia along 15 days. To conclude, micafungin diluted in NaCl 0.9% and stored in polypropylene syringes was chemically stable for at least 15 days at 25 °C in the dark. PMID:26187166

  20. 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

  1. Single carbon nanotube syringe: A model for the study of liquid transport through individual carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Chai, Guangyu; Chow, Lee

    2008-03-01

    The hollow structure of the carbon nanotubes (CNT) and their ability to translocate through plasma membrane of a living cell provide a significant chance to use them as a nano syringe for the delivery of therapeutically active molecules into a live cell. However, the size and the extremely high aspect ratio of the CNTs make the nano syringe device difficult to realize. We successfully prepared a monolithic multiwall CNT with a graphitic shield by chemical vapor deposition technique. The graphitic shield provides a handle which allows the manipulation of the supported CNTs. A single CNT syringe device is fabricated with focused ion beam technique. The well-controlled liquid transport through individual CNT is demonstrated.

  2. 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

  3. Cross-linked silicone coating: a novel prefilled syringe technology that reduces subvisible particles and maintains compatibility with biologics.

    PubMed

    Depaz, Roberto A; Chevolleau, Tzvetelina; Jouffray, Sébastien; Narwal, Roja; Dimitrova, Mariana N

    2014-05-01

    Prefilled syringes (PFSs) offer improvements in the delivery of drugs to patients compared with traditional vial presentations and are becoming necessities in an increasingly competitive biologics market. However, the development of a product in a PFS must take into account potential incompatibilities between the drug and the components of the syringe. One such component is silicone oil, which has previously been suggested to promote protein aggregation, loss of soluble protein, and an increase in the particulate content of injectable formulations. This study evaluated the particulate content in a model buffer system (polysorbate 80/phosphate-buffered saline) after agitation in glass syringes with a novel cross-linked silicone coating. We also evaluated the compatibility of two monoclonal antibodies with these syringes. We report that syringes with this novel coating, compared with standard siliconized syringes, exhibited reduced particle content and enhanced integrity of the lubricant layer as determined by reflectometry, optical microscopy, and time-of-flight secondary ion mass spectrometry measurements, while maintaining the desired functional properties of the syringe and the antibodies' stability profiles as determined by high-performance size-exclusion chromatography. Enhanced integrity of the lubricant coating led to significantly fewer subvisible particles in the liquid formulations, particularly after agitation stresses introduced by shipping of the syringes. PMID:24643773

  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. 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.

  6. 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; Rudin, S R; Bednarek, D R

    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.

  7. Estimation of the Force on the Syringe Tie-rods from Fringing

    E-print Network

    McDonald, Kirk

    SS304L or SS316L. · However Stainless Steel 17-4 PH was used. ­ This stainless steel is martensiticEstimation of the Force on the Syringe Tie-rods from Fringing Magnetic Fields Steve Kahn 5 April 2006 #12;Tie-rod location #12;#12;Tie-rod Specifications Indicate that They Should Be Non-Magnetic · 1

  8. STS-43 MS Lucid works with BIMDA-02 cell syringes on OV-104's middeck

    NASA Technical Reports Server (NTRS)

    1991-01-01

    STS-43 Mission Specialist (MS) Shannon W. Lucid works with Bioserve- Instrumentation Technology Associates Materials Dispersion Apparatus (BIMDA) cell syringes at the forward lockers on the middeck of Atlantis, Orbiter Vehicle (OV) 104. Fluorescent lighting fixtures are set up at Lucid's left on a mounting bracket and behind her.

  9. Improved Efficiency for Sample-Standard Bracketing with Syringe Driven Flow Injection System

    NASA Astrophysics Data System (ADS)

    Field, P.

    2013-12-01

    Sample-standard bracketing improves precision and corrects for mass bias drift in the determination of precise isotope ratios by MC-ICPMS. Lower m/z isotope systems suffer worse mass bias drift, so many determinations of isotope ratios below 100 amu require measurement of a standard between every sample in order to achieve the desired precision. A newly designed, syringe-driven, flow injection system precisely and accurately loads sample into a loop and injects it into the ICPMS at a user defined flow rate (10 - 1000uL/min). While sample is loaded onto the loop, a standard may be introduced into the ICPMS. Efficiency is dramatically improved by these discrete, parallel flow paths for standard and samples and minimal dead volume between the valve and the nebulizer. During the standard analysis, the sample flow path and uptake probe is rinsed, the sample-loading syringe is reset, and sample is loaded accurately and precisely into the loop. Alternatively, during the sample analysis, the standard syringe is reset. The benefits of this configuration include rapid wash out, uptake, and sample-standard bracketing; syringe-controlled sample volumes and flow rates; reduced sample consumption; and improved absolute detection limits.

  10. 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…

  11. [Aerobic blood sampling technique using the B 109-syringe (author's transl)].

    PubMed

    Andersen, L H; Thomsen, A

    1978-03-01

    A syringe (B 109 Radiometer) for arterial blood sampling with modified aerobic technique is described. The blood sampling and subsequent storage during 2 h in ice water induces no clinically significant changes in the pH, pCO2 and pO2 of the blood. PMID:25595

  12. 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

  13. Cosmic Calibration

    E-print Network

    Katrin Heitmann; David Higdon; Charles Nakhleh; Salman Habib

    2006-06-07

    The complexity and accuracy of current and future precision cosmology observational campaigns has made it essential to develop an efficient technique for directly combining simulation and observational datasets to determine cosmological and model parameters; a procedure we term calibration. Once a satisfactory calibration of the underlying cosmological model is achieved, independent predictions for new observations become possible. For this procedure to be effective, robust characterization of the uncertainty in the calibration process is highly desirable. In this Letter, we describe a statistical methodology which can achieve both of these goals. An application example based around dark matter structure formation simulations and a synthetic mass power spectrum dataset is used to demonstrate the approach.

  14. Cosmic Calibration

    E-print Network

    Heitmann, K; Nakhleh, C; Habib, S; Heitmann, Katrin; Higdon, David; Nakhleh, Charles; Habib, Salman

    2006-01-01

    The complexity and accuracy of current and future precision cosmology observational campaigns has made it essential to develop an efficient technique for directly combining simulation and observational datasets to determine cosmological and model parameters; a procedure we term calibration. Once a satisfactory calibration of the underlying cosmological model is achieved, independent predictions for new observations become possible. For this procedure to be effective, robust characterization of the uncertainty in the calibration process is highly desirable. In this Letter, we describe a statistical methodology which can achieve both of these goals. An application example based around dark matter structure formation simulations and a synthetic mass power spectrum dataset is used to demonstrate the approach.

  15. ATCA Calibrators

    NASA Astrophysics Data System (ADS)

    Stevens, Jamie; Edwards, Philip; Wark, Robin; Wieringa, Mark

    2010-04-01

    We propose to continue the ATCA calibrator database monitoring, with emphasis at mm wavelengths. We request 24 hours at the beginning of each of the 4 compact configurations in 2010APRS to carefully cross-calibrate a number of bright AGN and ultra-compact HII regions against Uranus for use by those observing in that array configuration. We will observe at the standard ATCA frequencies, and in response to any special requests by observers for non-standard frequencies.

  16. ATCA Calibrators

    NASA Astrophysics Data System (ADS)

    Stevens, Jamie; Edwards, Philip; Wark, Robin; Wieringa, Mark

    2011-04-01

    We propose to continue the ATCA calibrator database monitoring, with emphasis at mm wavelengths. We request 24 hours at the beginning of each configuration in 2011APRS to carefully cross-calibrate a number of bright AGN and ultra-compact HII regions against Uranus and 1934-638 for use by those observing in that array configuration. We will observe at the standard ATCA frequencies, and in response to any special requests by observers for non-standard frequencies.

  17. ATCA Calibrators

    NASA Astrophysics Data System (ADS)

    Stevens, Jamie; Edwards, Philip; Wark, Robin; Wieringa, Mark

    2011-10-01

    We propose to continue the ATCA calibrator database monitoring, with emphasis at cm wavelengths. We request any unallocated time in 2011OCTS to carefully cross-calibrate a number of bright AGN and ultra-compact HII regions against Uranus and 1934-638 for use by those observing in that array configuration. We will observe at the standard ATCA frequencies, and in response to any special requests by observers for non-standard frequencies.

  18. ATCA Calibrators

    NASA Astrophysics Data System (ADS)

    Stevens, Jamie; Edwards, Philip; Wark, Robin; Wieringa, Mark

    2014-04-01

    We propose to continue the ATCA calibrator database monitoring, with emphasis at mm wavelengths. We request 24 hours at the beginning of each configuration in 2011APRS to carefully cross-calibrate a number of bright AGN and ultra-compact HII regions against Uranus and 1934-638 for use by those observing in that array configuration. We will observe at the standard ATCA frequencies, and in response to any special requests by observers for non-standard frequencies.

  19. ATCA Calibrators

    NASA Astrophysics Data System (ADS)

    Stevens, Jamie; Edwards, Philip; Wark, Robin; Wieringa, Mark

    2012-10-01

    We propose to continue the ATCA calibrator database monitoring. We request 24 hours at the beginning five configurations in 2012OCTS to carefully cross-calibrate a number of bright AGN and ultra-compact HII regions against Uranus and 1934-638 for use by those observing in that array configuration. We will observe at the standard ATCA frequencies, and in response to any special requests by observers for non-standard frequencies.

  20. ATCA Calibrators

    NASA Astrophysics Data System (ADS)

    Stevens, Jamie; Edwards, Philip; Wark, Robin; Wieringa, Mark

    2012-04-01

    We propose to continue the ATCA calibrator database monitoring, with emphasis at mm wavelengths. We request 24 hours at the beginning five configurations in 2012APRS to carefully cross-calibrate a number of bright AGN and ultra-compact HII regions against Uranus and 1934-638 for use by those observing in that array configuration. We will observe at the standard ATCA frequencies, and in response to any special requests by observers for non-standard frequencies.

  1. [Comparison of the absorbed dose at calibration depth of photon beams using the Japan Society of Medical Physics 12 beam quality conversion factor in the presence or absence of a waterproofing sleeve].

    PubMed

    Kinoshita, Naoki; Takemura, Akihiro; Kita, Akinobu; Murai, Emi; Nishimoto, Yasuhiro; Toi, Akiko; Shimada, Masato; Sasamoto, Kouhei; Adachi, Toshiki

    2013-10-01

    In standard external beam radiotherapy dosimetry, which is based on absorbed dose by water, the absorbed dose at any calibration depth is calculated using the same beam quality conversion factor, regardless of the presence or absence of a waterproofing sleeve. In this study, we evaluated whether there were differences between absorbed doses at calibration depths calculated using a beam quality conversion factor including a wall correction factor that corresponds to a waterproofing sleeve thickness of 0.3 mm, and without a waterproofing sleeve. The Japan Society of Medical Physics (JSMP) has reported that the uncertainty of the results using a beam quality conversion factor that included a wall correction factor corresponding to a waterproofing sleeve thickness of 0.3 mm, regardless of the presence or absence of the sleeve, was 0.2%. This uncertainty proved to be in agreement with the reported range. PMID:24140905

  2. Field calibration of multi-scattering correction factor for aethalometer aerosol absorption coefficient during CAPMEX Campaign, 2008

    NASA Astrophysics Data System (ADS)

    Kim, J. H.; Kim, S. W.; Yoon, S. C.; Park, R.; Ogren, J. A.

    2014-12-01

    Filter-based instrument, such as aethalometer, is being widely used to measure equivalent black carbon(EBC) mass concentration and aerosol absorption coefficient(AAC). However, many other previous studies have poited that AAC and its aerosol absorption angstrom exponent(AAE) are strongly affected by the multi-scattering correction factor(C) when we retrieve AAC from aethalometer EBC mass concentration measurement(Weingartner et al., 2003; Arnott et al., 2005; Schmid et al., 2006; Coen et al., 2010). We determined the C value using the method given in Weingartner et al. (2003) by comparing 7-wavelngth aethalometer (AE-31, Magee sci.) to 3-wavelength Photo-Acoustic Soot Spectrometer (PASS-3, DMT) at Gosan climate observatory, Korea(GCO) during Cheju ABC plume-asian monsoon experiment(CAPMEX) campaign(August and September, 2008). In this study, C was estimated to be 4.04 ± 1.68 at 532 nm and AAC retrieved with this value was decreased as approximately 100% as than that retrieved with soot case value from Weingartner et al (2003). We compared the AAC determined from aethalomter measurements to that from collocated Continuous Light Absorption Photometer (CLAP) measurements from January 2012 to December 2013 at GCO and found good agreement in both AAC and AAE. This result suggests the determination of site-specific C is crucially needed when we calculate AAC from aethalometer measurements.

  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. State laws, syringe exchange, and HIV among persons who inject drugs in the United States: History and effectiveness.

    PubMed

    Bramson, Heidi; Des Jarlais, Don C; Arasteh, Kamyar; Nugent, Ann; Guardino, Vivian; Feelemyer, Jonathan; Hodel, Derek

    2015-05-01

    In 1981, when acquired immune deficiency syndrome (AIDS) was first observed among persons who inject drugs, almost all US states had laws criminalizing the possession and distribution of needles and syringes for injecting illicit drugs. We reviewed changes to these laws to permit 'syringe exchanges' and the provision of public funding for such programs. Most of the changes in law occurred during the 1990s, 5-10 years later than in many other countries. Public funding of syringe exchanges is associated with lower rates of human immunodeficiency virus (HIV) infection, greater numbers of syringes distributed (a possible causal mechanism), and greater numbers of health and social services provided. Experience in the United states may prove useful in other countries: state, provincial, and local governments may need to move ahead of central governments in addressing HIV infection among persons who inject drugs. PMID:25590514

  5. 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.

  6. Race and Distance Effects on Regular Syringe Exchange Program Use and Injection Risks: A Geobehavioral Analysis

    PubMed Central

    Metzger, David S.

    2010-01-01

    Objectives. We conducted “geobehavioral” analyses by race to understand how distances among injection drug users' (IDUs') residences, drug purchase and use locations, and syringe exchange programs (SEPs) are associated with injection behaviors. Methods. Data were from the HIV Prevention Trial Network 037 (2002–2006) site in Philadelphia, Pennsylvania, a randomized study evaluating the efficacy of a network-oriented HIV prevention intervention for IDUs. At prescreening, participants were asked the nearest intersections to their residence, where they buy and use drugs, and about their injection behaviors. Results. Geographic distances had independent and interactive effects on injection risk behaviors and SEP use. Blacks, regardless of distance, were less likely than Whites to inject in public places (odds ratio [OR] = 0.62; 95% confidence interval [CI] = 0.43, 0.90), to use syringes after someone else (OR = 0.27; 95% CI = 0.19, 0.38), and to access syringes from SEPs (OR = 2.08; 95% CI = 1.48, 2.92). Latinos' injection behaviors were more distance-dependent than Blacks' or Whites'. Conclusions. Distances among IDUs' homes, drug purchase and injecting sites, and prevention resources affected safe injection practices differentially by race. Understanding individuals' geographic relation to the risks and resources that surround them is an important aspect of understanding effects of the environment on health and behavior and the development of targeted interventions. PMID:20395589

  7. Effectiveness of structural-level needle/syringe programs to reduce HCV and HIV infection among people who inject drugs: a systematic review.

    PubMed

    Abdul-Quader, Abu S; Feelemyer, Jonathan; Modi, Shilpa; Stein, Ellen S; Briceno, Alya; Semaan, Salaam; Horvath, Tara; Kennedy, Gail E; Des Jarlais, Don C

    2013-11-01

    Needle-syringe programs (NSP) have been effective in reducing HIV and hepatitis C (HCV) infection among people who inject drugs (PWID). Achieving sustainable reductions in these blood-borne infections requires addressing structural factors so PWID can legally access NSP services. Systematic literature searches collected information on NSP coverage and changes in HIV or HCV infection prevalence or incidence at the population level. Included studies had to document biomarkers (HIV or HCV) coupled with structural-level NSP, defined by a minimum 50 % coverage of PWID and distribution of 10 or more needles/syringe per PWID per year. Fifteen studies reported structural-level NSP and changes in HIV or HCV infection prevalence/incidence. Nine reported decreases in HIV prevalence, six in HCV infection prevalence, and three reported decreases in HIV incidence. The results support NSP as a structural-level intervention to reduce population-level infection and implementation of NSP for prevention and treatment of HIV and HCV infection. PMID:23975473

  8. 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 10.00 mL 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 0.1-3000 ngmL(-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 (0.25-0.50 ngmL(-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

  9. A clinical evaluation of four non-Luer spinal needle and syringe systems.

    PubMed

    Kinsella, S M; Goswami, A; Laxton, C; Kirkham, L; Wharton, N; Bowen, M

    2012-11-01

    We performed an evaluation of non-Luer spinal devices supplied by four manufacturers or suppliers: Polymedic; Pajunk; Sarstedt; and Smiths. For each supplier, 100 evaluations were performed using a 25-G 90-mm spinal needle, 3-ml syringe, 5-ml syringe and filter needle; for comparison, 100 evaluations were performed with our standard Luer equipment. The non-Luer devices were associated with more qualitative problems compared with the Luer devices, for example, poor feel of dural puncture (9-32% vs 10%, respectively), poor observation of cerebrospinal fluid in the hub (3-27% vs 0%), and connection problem of the syringe to the spinal needle (7-33% vs 0%). There was also more frequent failure to achieve the spinal injection due to equipment-related causes (4-7% vs 0%, respectively). Median (IQR [range]) numeric satisfaction scores for the spinal needles were: Luer 10 (9-10 [7-10]); Polymedic 7 (4-8 [0-10]; Pajunk 7 (5-8 [0-10]); Sarstedt 7 (6-8 [0-10]); and Smiths 9 (7-10 [0-10]) (p<0.0001). Satisfaction scores for all spinal equipment were: Luer 10 (9-10 [5-10]); Polymedic 8 (6-8 [0-10]); Pajunk 7 (5-7 [1-9]); Sarstedt 8 (6-8 [0-10]); and Smiths 8 (8-9 [2-10]) (p<0.0001). Between 21% and 75% of non-Luer evaluations were rated with satisfaction worse than the usual Luer needle compared with 0-10% rated better, depending on the needle type. Between 22% and 76% of non-Luer evaluations were rated with satisfaction worse than the usual Luer equipment compared with 0-14% rated better. Specific concerns included poor feel of tissue planes and observation of cerebrospinal fluid (Polymedic), difficulty with connection of the syringe to the spinal needle and trocar removal (Pajunk), poor feel of tissue planes and needle flexibility (Sarstedt) and difficulty with connection of the syringe to the spinal needle (Smiths). We could not demonstrate a short-term learning curve for the new devices. Decisions on purchasing and implementation of the new non-Luer equipment will have to acknowledge that clinicians may have greater technical problems and reduced satisfaction compared with the current equipment. PMID:22881215

  10. Pseudo Linear Gyro Calibration

    NASA Technical Reports Server (NTRS)

    Harman, Richard; Bar-Itzhack, Itzhack Y.

    2003-01-01

    Previous high fidelity onboard attitude algorithms estimated only the spacecraft attitude and gyro bias. The desire to promote spacecraft and ground autonomy and improvements in onboard computing power has spurred development of more sophisticated calibration algorithms. Namely, there is a desire to provide for sensor calibration through calibration parameter estimation onboard the spacecraft as well as autonomous estimation on the ground. Gyro calibration is a particularly challenging area of research. There are a variety of gyro devices available for any prospective mission ranging from inexpensive low fidelity gyros with potentially unstable scale factors to much more expensive extremely stable high fidelity units. Much research has been devoted to designing dedicated estimators such as particular Extended Kalman Filter (EKF) algorithms or Square Root Information Filters. This paper builds upon previous attitude, rate, and specialized gyro parameter estimation work performed with Pseudo Linear Kalman Filter (PSELIKA). The PSELIKA advantage is the use of the standard linear Kalman Filter algorithm. A PSELIKA algorithm for an orthogonal gyro set which includes estimates of attitude, rate, gyro misalignments, gyro scale factors, and gyro bias is developed and tested using simulated and flight data. The measurements PSELIKA uses include gyro and quaternion tracker data.

  11. Needle-free transdermal delivery using PLGA nanoparticles: effect of particle size, injection pressure and syringe orifice diameter.

    PubMed

    Park, Chan Hee; Tijing, Leonard D; Kim, Cheol Sang; Lee, Kang-Min

    2014-11-01

    The aim of this study is to investigate the effects of particle size and other injection factors on the skin penetration of nanoparticles delivered with a needle-free injector. Experimental and simulation tests were carried out at various parameters. In addition to testing different sizes of nanoparticles, we also observed the effects of several injection pressures and syringe orifice diameters (SOD) on the dispersion pattern of the nanoparticles after injection. Our results showed that as the nanoparticle size increased from 45 nm to 452 nm, the resulting puncture opening, channel diameter, and depth of the nanoparticle dispersion decreased, but the width of the dispersion increased. Conversely, as the SOD increased, the puncture opening, channel diameter, and depth of the dispersion increased, but width of the dispersion decreased. Increasing the injection pressure also decreased the size, depth, and width of the puncture opening. These results identify how these three parameters affect nanoparticle delivery from a needle-free injector; therefore, our findings will be beneficial for optimization and further study of needle-free injectors as a mechanism for transdermal delivery of nanoparticles. PMID:25456991

  12. Temperature Calibration

    NASA Astrophysics Data System (ADS)

    Wang, A. L.

    2013-12-01

    Accuracy of temperature measurements is vital to many experiments. In this project, we design an algorithm to calibrate thermocouples' temperature measurements. To collect data, we rely on incremental heating to calculate the diffusion coefficients of argon through sanidine glasses. These coefficients change according to an arrhenius equation that depends on temperature, time, and the size and geometry of the glass; thus by fixing the type of glass and the time of each heating step, we obtain many data points by varying temperature. Because the dimension of temperature is continuous, obtaining data is simpler in noble gas diffusion experiments than in measuring the discrete melting points of various metals. Due to the nature of electrical connections, the need to reference to the freezing point of ice, thermal gradients in the sample, the time dependent dissipation of heat into the surroundings, and other inaccuracies with thermocouple temperature measurements, it is necessary to calibrate the experimental measurements with the expected or theoretical measurements. Since the diffusion constant equation is exponential with the inverse of temperature, we transform the exponential D vs T graph into a linear log(D) vs 1/T graph. Then a simple linear regression yields the equation of the line, and we find a mapping function from the experimental temperature to the expected temperature. By relying on the accuracy of the diffusion constant measurement, the mapping function provides the temperature calibration. Theoretical (Temperature, Diffusion Coefficient, Fractional Loss, Zeta)

  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. 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

  15. Primary and secondary analysis of local elected officials' decisions to support or oppose pharmacy sale of syringes in California.

    PubMed

    Backes, Glenn; Rose, Valerie J

    2010-07-01

    Under California law, local governments may authorize pharmacies within their jurisdictions to sell ten or fewer syringes to an adult without prescription, proof of identity, or proof of medical need. Local governments may simultaneously exempt adults from prosecution for violation of state drug paraphernalia codes for possession of ten or fewer syringes for personal use. Both of these provisions are temporary and sunset on December 31, 2010, unless subsequent state legislation amends that date. The objective of our study was to ascertain how and why local policymakers made their decisions regarding non-prescription syringe sale (NPSS). We examined influences on their decisions, including specific messengers and the arguments that were most salient to their decision making. We selected jurisdictions that were geographically representative of California counties; those with and without syringe exchange programs, and those that had passed or rejected NPSS. We conducted nine semi-structured interviews in five jurisdictions. To enrich primary data collection, we analyzed secondary data by reviewing audio, video, and written transcripts of public hearings and newspaper coverage in five jurisdictions, including three jurisdictions without primary interview data. Among proponents of NPSS, we identified common themes, including: (1) public health research provided conclusive evidence for reduction in HIV and hepatitis transmission without problems of crime, drug use, or unsafe discard of syringes; (2) the local health officer was the key to influencing local policymakers; (3) recall of prior debates over syringe exchange served to inform their decision making; and (4) a lack of local opposition or controversy. Common concerns among opponents of NPSS included: (1) that there would be an increase in unsafe discard of syringes; (2) loss of an important law enforcement tool; (3) that drug users were incapable of desired behavior change; and (4) that research was inconclusive, or proved that syringe access would not work in reducing rates of disease. Themes held in common by proponents and opponents of NPSS were identified as well. Syringe access through NPSS is in fact supported by a robust body of public health research and is considered an important component of a comprehensive strategy to reduce HIV and hepatitis transmission. Our study highlights the importance of understanding the perspectives of elected officials in order to ameliorate their concerns without undermining the public health goal of reducing death, disease, and suffering in at-risk communities. PMID:20352356

  16. STS-47 Payload Specialist Mohri holds sample syringe during SLJ experiment

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-47 Payload Specialist Mamoru Mohri holds sample syringe while conducting Studies on the Effects of Microgravity on the Ultrastructure and Function of Cultured Mammalian Cells (KIDNEY CELLS). Mohri, wearing a lightweight headset, works inside the Spacelab Japan (SLJ) science module aboard Endeavour, Orbiter Vehicle (OV) 105. In the background are the NASDA Material Sciences Rack 10 with field sequential (FS) crew cabin camera attached and the SLJ end cone with a banner from Auburn University and portraits of the backup payload specialists. Mohri represents Japan's National Space Development Agency (NASDA).

  17. 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

  18. Estimation of lead in biological samples of oral cancer patients chewing smokeless tobacco products by ionic liquid-based microextraction in a single syringe system.

    PubMed

    Arain, Sadaf S; Kazi, Tasneem G; Arain, Asma J; Afridi, Hassan I; Arain, Muhammad B; Brahman, Kapil D; Naeemullah; Panhwar, Abdul H; Arain, Mariam S

    2015-08-01

    Several studies have reported that the chewing habit of smokeless tobacco (SLT) has been associated with oral cancer. The aim of the present study was to evaluate the trace levels of lead (Pb) in biological samples (blood, scalp hair) of oral cancer patients and referents of the same age group (range 30-60 years). As the concentrations of Pb are very low in biological samples, so a simple and efficient ionic liquid-based microextraction in a single syringe system has been developed, as a prior step to determination by flame atomic absorption spectrometry. In this procedure, the hydrophobic chelates of Pb with ammonium pyrrolidinedithiocarbamate (APDC) were extracted into fine droplets of 1-butyl-3-methylimidazolium hexafluorophosphate [C4MIM][PF6] within a syringe while using Triton X-114 as a dispersant. Factors influencing the microextraction efficiency and determination, such as pH of the sample, volume of [C4MIM][PF6] and Triton X-114, ligand concentration, and incubation time, were studied. To validate the proposed method, certified reference materials were analyzed and the results of Pb(2+) were in good agreement with certified values. At optimum experimental values of significant variables, detection limit and enhancement factor were found to be 0.412 ?g/L and 80, respectively. The coexisting ions showed no obvious negative outcome on Pb preconcentration. The proposed method was applied satisfactorily for the preconcentration of Pb(2+) in acid-digested SLT and biological samples of the study population. It was observed that oral cancer patients who consumed different SLT products have 2-3-fold higher levels of Pb in scalp hair and blood samples as compared to healthy referents (p?

  19. A study of water flow efficiency in dental air/water syringe tips after repeated chemiclave sterilization.

    PubMed

    Asher, R S; Newman, S; Ohmart, S

    1994-01-01

    In response to the need for dental office asepsis, many practitioners sterilize dental air/water syringe tips for each patient. It is hypothesized that repeated sterilization would lead to internal corrosion restricting the water flow. This study was conducted to evaluate consistency of water flow in a series of dental air/water syringe tips after multiple cycles of Chemiclave sterilization. An apparatus was constructed to deliver water at the same pressure and flow to each syringe tip. The flow rates between tips were significantly different (P < .001). Average water flow, in grams per minute, was determined by ten repeat trials for each tip. The tips were retested after 1, 5, and 25 cycles of Chemiclave sterilization. None of tips showed a decrease in water flow efficiency after repeated sterilization cycles. No difference in ability to remove etchant from enamel and dentin could be demonstrated using a 10-second wash. PMID:8054288

  20. Experimental (FT-IR, FT-Raman, 1H, 13C NMR) and theoretical study of alkali metal syringates

    NASA Astrophysics Data System (ADS)

    ?wis?ocka, Renata

    2013-07-01

    In this work the influence of lithium, sodium, potassium, rubidium and cesium on the electronic system of the syringic acid (4-hydroxy-3,5-dimethoxybenzoic acid) was studied. This paper presents spectroscopic vibrations (FT-IR, FT-Raman) and NMR (1H and 13C) study of the series of alkali metal syringates from lithium to cesium syringates. Characteristic shifts of band wavenumbers and changes in band intensities along the metal series were observed. Optimized geometrical structures of the studied compounds were calculated by the B3LYP method using the 6-311++G?? basis set. Aromaticity indices, atomic charges, dipole moments and energies were also calculated. The theoretical wavenumbers and intensities of IR and NMR spectra were obtained. The calculated parameters were compared to experimental characteristics of studied compounds.

  1. Experimental (FT-IR, FT-Raman, 1H, 13C NMR) and theoretical study of alkali metal syringates.

    PubMed

    ?wis?ocka, Renata

    2013-07-01

    In this work the influence of lithium, sodium, potassium, rubidium and cesium on the electronic system of the syringic acid (4-hydroxy-3,5-dimethoxybenzoic acid) was studied. This paper presents spectroscopic vibrations (FT-IR, FT-Raman) and NMR ((1)H and (13)C) study of the series of alkali metal syringates from lithium to cesium syringates. Characteristic shifts of band wavenumbers and changes in band intensities along the metal series were observed. Optimized geometrical structures of the studied compounds were calculated by the B3LYP method using the 6-311++G(**) basis set. Aromaticity indices, atomic charges, dipole moments and energies were also calculated. The theoretical wavenumbers and intensities of IR and NMR spectra were obtained. The calculated parameters were compared to experimental characteristics of studied compounds. PMID:23664591

  2. Fibre architecture and song activation rates of syringeal muscles are not lateralized in the European starling

    PubMed Central

    Uchida, A. M.; Meyers, R. A.; Cooper, B. G.; Goller, F.

    2010-01-01

    The songbird vocal organ, the syrinx, is composed of two sound generators, which are independently controlled by sets of two extrinsic and four intrinsic muscles. These muscles rank among the fastest vertebrate muscles, but the molecular and morphological foundations of this rapid physiological performance are unknown. Here we show that the four intrinsic muscles in the syrinx of male European starlings (Sturnus vulgaris) are composed of fast oxidative and superfast fibres. Dorsal and ventral tracheobronchialis muscles contain slightly more superfast fibres relative to the number of fast oxidative fibres than dorsal and ventral syringealis muscles. This morphological difference is not reflected in the highest, burst-like activation rate of the two muscle groups during song as assessed with electromyographic recordings. No difference in fibre type ratio was found between the corresponding muscles of the left and right sound generators. Airflow and electromyographic measurements during song indicate that maximal activation rate and speed of airflow regulation do not differ between the two sound sources. Whereas the potential for high-speed muscular control exists on both sides, the two sound generators are used differentially for modulation of acoustic parameters. These results show that large numbers of superfast fibre types are present in intrinsic syringeal muscles of a songbird, providing further confirmation of rapid contraction kinetics. However, syringeal muscles are composed of two fibre types which raises questions about the neuromuscular control of this heterogeneous muscle architecture. PMID:20228343

  3. [Characterization by thin layer chromatography of benzothiazole derivatives and beta-sitosterol leached by disposable syringes].

    PubMed

    Airaudo, C B; Gayte-Sorbier, A; Momburg, R; Laurent, P

    1986-02-28

    A thin-layer chromatographic study of 2-mercaptobenzothiazole, 2-(methylthio)benzothiazole, 2-(2-hydroxy-ethylthio)benzothiazole, 2-hydroxybenzothiazole, zinc 2-mercaptobenzothiazolate, mercaptobenzothiazole disulfide, and beta-sitosterol with three developing solvents and eleven spray reagents is reported. A simple method is described which highlights the leaching of 2-mercaptobenzothiazole and 2-(2-hydroxy-ethylthio)benzothiazole from the rubber plunger-seals of disposable syringes: contact of rubber with bidistilled water, extraction of this liquid with chloroform, chromatography on silica gel with the solvents previously studied and spraying with N-chloro-2,6-dichloro-p-benzoquinone monoimine. The method may also be used to discriminate those syringes sterilized with ethylene oxide, the only ones able to leach 2-(2-hydroxy-ethylthio)benzothiazole, from those sterilized by irradiation. Owing to the beta-sitosterol traces leached, it may also be used to investigate whether the plunger-seals are made of natural rubber. The toxic effects of the compounds leached are briefly reported. PMID:3700529

  4. Cartridge syringe vs computer controlled local anesthetic delivery system: Pain related behaviour over two sequential visits – a randomized controlled trial

    PubMed Central

    Thoppe-Dhamodhara, Yogesh-Kumar; Asokan, Sharath; John, Baby-John; Pollachi-Ramakrishnan, GeethaPriya; Ramachandran, Punithavathy; Vilvanathan, Praburajan

    2015-01-01

    Background Local anesthetic injection is one of the most anxiety provoking procedure in dentistry. Knowledge about change in pain related behaviour during consecutive visits helps in and scheduling of treatment procedures and management of children in dental clinic. Aim To compare the pain perception, behavioural response and the associated change in physiological parameters while receiving local anesthesia injection with cartridge syringe and computer controlled local anesthetic delivery system (CCLAD) over two consecutive visits. Material and Methods In this randomized controlled cross over trial, 120 children aged 7 – 11 years were randomly divided into group A: receiving injections with CCLAD during first visit; group B: receiving injections with cartridge syringe during first visit. The physiological parameters (heart rate and blood pressure) were recorded before and during injection procedure. Objective evaluation of disruptive behaviour and subjective evaluation of pain perceived were done using Face Legs Activity Cry Consolability (FLACC) scale and modified facial image scale (FIS) respectively. Results No statistical difference in pain response (p= 0.164) and disruptive behaviour (p = 0.120) between cartridge syringe and CCLAD injections were seen during the first visit although the latter showed lesser scores. However, during the second visit there were significant increase in pain response (p = 0.004) and disruptive behaviour (p = 0.006) in cartridge syringe group with an associated increase in heart rate. Conclusions Injections with CCLAD produced lesser pain ratings and disruptive behaviour than cartridge syringe in children irrespective of order of visit. Key words:Behaviour, cartridge syringe, CCLAD, local anesthesia. PMID:26535099

  5. Molecularly imprinted solid phase extraction in a syringe filter for determination of triazine herbicides in Radix Paeoniae Alba by ultra-fast liquid chromatography.

    PubMed

    Li, Xinpei; Wang, Yuanpeng; Sun, Qun; Xu, Bo; Yu, Yong; Wang, Xinghua

    2016-02-01

    A novel, cost-effective and simple solid phase extraction (SPE) method, by using a syringe connected with a nylon membrane filter as the adsorbent container, was developed for the extraction of triazine herbicides from Radix Paeoniae Alba (RPA) samples. The selective molecularly imprinted polymers (MIPs) synthesized with the template of atrazine were employed as the adsorbents for the enrichment and purification of analytes. The extraction parameters, including the volume and type of loading solvent, the type of washing solvent and eluting solvent, were investigated. Under the optimized conditions, the final extracts were analyzed by ultra-fast liquid chromatography (UFLC). Recoveries of the developed method range from 92.4% to 107.3% with intra- and inter-day relative standard deviations (RSDs) lower than 8.2%. The calibration curve is linear in the concentration range of 0.005-2.4µgg(-1) for desmetryn, atrazine and terbumeton, and 0.005-1.5µgg(-1) for dimethametryn and dipropetryn, with the correlation coefficient (R(2)) higher than 0.9995. The limits of detection (LODs) of five triazine herbicides are in the range of 0.09-0.39ngg(-1), which are lower than the maximum residue levels (MRLs) established by various official organizations. Analytical results of three real Radix Paeoniae Alba samples indicate that the proposed method is cost-effective and easy-to-use than other routine pretreatment methods. PMID:26653483

  6. Using Pharmacies in a Structural Intervention to Distribute Low Dead Space Syringes to Reduce HIV and HCV Transmission in People Who Inject Drugs

    PubMed Central

    Johnson, Terence L.; Zule, William A.; Carda-Auten, Jessica; Golin, Carol E.

    2015-01-01

    Ongoing injection drug use contributes to the HIV and HCV epidemics in people who inject drugs. In many places, pharmacies are the primary source of sterile syringes for people who inject drugs; thus, pharmacies provide a viable public health service that reduces blood-borne disease transmission. Replacing the supply of high dead space syringes with low dead space syringes could have far-reaching benefits that include further prevention of disease transmission in people who inject drugs and reductions in dosing inaccuracies, medication errors, and medication waste in patients who use syringes. We explored using pharmacies in a structural intervention to increase the uptake of low dead space syringes as part of a comprehensive strategy to reverse these epidemics. PMID:25880955

  7. Using Pharmacies in a Structural Intervention to Distribute Low Dead Space Syringes to Reduce HIV and HCV Transmission in People Who Inject Drugs.

    PubMed

    Oramasionwu, Christine U; Johnson, Terence L; Zule, William A; Carda-Auten, Jessica; Golin, Carol E

    2015-06-01

    Ongoing injection drug use contributes to the HIV and HCV epidemics in people who inject drugs. In many places, pharmacies are the primary source of sterile syringes for people who inject drugs; thus, pharmacies provide a viable public health service that reduces blood-borne disease transmission. Replacing the supply of high dead space syringes with low dead space syringes could have far-reaching benefits that include further prevention of disease transmission in people who inject drugs and reductions in dosing inaccuracies, medication errors, and medication waste in patients who use syringes. We explored using pharmacies in a structural intervention to increase the uptake of low dead space syringes as part of a comprehensive strategy to reverse these epidemics. PMID:25880955

  8. 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 ...

  9. Development of new portable miniaturize solid phase microextraction of silver-APDC complex using micropipette tip in-syringe system couple with electrothermal atomic absorption spectrometry.

    PubMed

    Naeemullah; Kazi, Tasneem Gul; Afridi, Hassan Imran; Shah, Faheem; Arain, Sadaf Sadia; Arain, Salma Aslam; Panhwar, Abdul Haleem; Arain, Mariam Shahzadi; Samoon, Muhammad Kashif

    2016-02-01

    An innovative and simple miniaturized solid phase microextraction (M-SPME) method, was developed for preconcentration and determination of silver(I) in the fresh and waste water samples. For M-SPME, a micropipette tip packed with activated carbon cloth (ACC) as sorbent, in a syringe system. The size, morphology and elemental composition of ACC before and after adsorption of analyte have been characterized by scanning electron microscopy and energy dispersive spectroscopy. The sample solution treated with a complexing reagent, ammonium pyrrolidine dithiocarbamate (APDC), was drawn into the syringe filled with ACC and dispensed manually for 2 to 10 aspirating/dispensing cycle. Then the Ag- complex sorbed on the ACC in micropipette was quantitatively eluted by drawing and dispensing of different concentrations of acids for 2 to 5 aspirating/dispensing cycles. The extracted Ag ions with modifier were injected directly into the electrothermal atomic absorption spectrometry for analysis. The influence of different variables on the extraction efficiency, including the concentration of ligand, pH, sample volume, eluent type, concentration and volume was investigated. Validity and accuracy of the developed method was checked by the standard addition method. Reliability of the proposed methodology was checked by the relative standard deviation (%RSD), which was found to be <5%. Under the optimized experimental variables, the limits of detection (LOD) and enhancement factors (EF), were obtained to be 0.86ngL(-1) and 120, respectively. The proposed method was successfully applied for the determination of trace levels of silver ions in fresh and waste water samples. PMID:26520476

  10. 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

  11. Improved wide-angle, fisheye and omnidirectional camera calibration

    NASA Astrophysics Data System (ADS)

    Urban, Steffen; Leitloff, Jens; Hinz, Stefan

    2015-10-01

    In this paper an improved method for calibrating wide-angle, fisheye and omnidirectional imaging systems is presented. We extend the calibration procedure proposed by Scaramuzza et al. by replacing the residual function and joint refinement of all parameters. In doing so, we achieve a more stable, robust and accurate calibration (up to factor 7) and can reduce the number of necessary calibration steps from five to three. After introducing the camera model and highlighting the differences from the current calibration procedure, we perform a comprehensive performance evaluation using several data sets and show the impact of the proposed calibration procedure on the calibration results.

  12. MOF as a syringe pump for the controlled release of iodine catalyst in the synthesis of meso-thienyl dipyrromethanes.

    PubMed

    Rangaraj, Prasath; Parshamoni, Srinivasulu; Konar, Sanjit

    2015-11-01

    In a new concept, an iodine loaded amine functionalized MOF was employed as a syringe pump for the slow release of iodine as a catalyst in the synthesis of thienyl dipyrromethanes under ambient conditions and turned out to be successful. The catalytic activities were compared with an isoreticular non-functionalized MOF and other conventional catalysts. PMID:26348100

  13. Patterns of sexual commerce among women at US Syringe Exchange Programs.

    PubMed

    Braine, Naomi; Desjarlais, Don C; Goldblatt, Cullen; Zadoretzky, Cathy; Turner, Charles

    2006-01-01

    In the USA, the majority of research on sex work has examined the experiences of women recruited from social locations commonly referred to as the 'sex industry', such as street strolls or escort services. This paper presents data from female syringe exchange participants who had sold sex in the last 30 days. The women interviewed for this study report a much broader array of commercial transactions than found in previous US studies, including selling sex to women, paying men for sex, and considerable role fluidity between buying and selling. In addition, approximately one-third of the women report only selling sex 1 day per week or less, and appear to be more socio-economically stable than women who sell sex more often. We argue that this data suggests the existence of an array of commercial sexual transactions outside of the socially recognized sex industry, and that social location may affect condom use. PMID:16846939

  14. Anterior and middle superior alveolar nerve block for anesthesia of maxillary teeth using conventional syringe

    PubMed Central

    Velasco, Ignacio; Soto, Reinaldo

    2012-01-01

    Background: Dental procedures in the maxilla typically require multiple injections and may inadvertently anesthetize facial structures and affect the smile line. To minimize these inconveniences and reduce the number of total injections, a relatively new injection technique has been proposed for maxillary procedures, the anterior and middle superior alveolar (AMSA) nerve block, which achieves pulpal anesthesia from the central incisor to second premolar through palatal approach with a single injection. The purpose of this article is to provide background information on the anterior and middle superior alveolar nerve block and demonstrate its success rates of pulpal anesthesia using the conventional syringe. Materials and Methods: Thirty Caucasian patients (16 men and 14 women) with an average age of 22 years-old, belonging to the School of Dentistry of Los Andes University, were selected. All the patients received an AMSA nerve block on one side of the maxilla using the conventional syringe, 1 ml of lidocaine 2% with epinephrine 1:100.000 was injected to all the patients. Results: The AMSA nerve block obtained a 66% anesthetic success in the second premolar, 40% in the first premolar, 60% in the canine, 23.3% in the lateral incisor, and 16.7% in the central incisor. Conclusions: Because of the unpredictable anesthetic success of the experimental teeth and variable anesthesia duration, the technique is disadvantageous for clinical application as the first choice, counting with other techniques that have greater efficacy in the maxilla. Although, anesthetizing the teeth without numbing the facial muscles may be useful in restorative dentistry. PMID:23559916

  15. Syringe Injectable Electronics: Precise Targeted Delivery with Quantitative Input/Output Connectivity.

    PubMed

    Hong, Guosong; Fu, Tian-Ming; Zhou, Tao; Schuhmann, Thomas G; Huang, Jinlin; Lieber, Charles M

    2015-10-14

    Syringe-injectable mesh electronics with tissue-like mechanical properties and open macroporous structures is an emerging powerful paradigm for mapping and modulating brain activity. Indeed, the ultraflexible macroporous structure has exhibited unprecedented minimal/noninvasiveness and the promotion of attractive interactions with neurons in chronic studies. These same structural features also pose new challenges and opportunities for precise targeted delivery in specific brain regions and quantitative input/output (I/O) connectivity needed for reliable electrical measurements. Here, we describe new results that address in a flexible manner both of these points. First, we have developed a controlled injection approach that maintains the extended mesh structure during the "blind" injection process, while also achieving targeted delivery with ca. 20 ?m spatial precision. Optical and microcomputed tomography results from injections into tissue-like hydrogel, ex vivo brain tissue, and in vivo brains validate our basic approach and demonstrate its generality. Second, we present a general strategy to achieve up to 100% multichannel I/O connectivity using an automated conductive ink printing methodology to connect the mesh electronics and a flexible flat cable, which serves as the standard "plug-in" interface to measurement electronics. Studies of resistance versus printed line width were used to identify optimal conditions, and moreover, frequency-dependent noise measurements show that the flexible printing process yields values comparable to commercial flip-chip bonding technology. Our results address two key challenges faced by syringe-injectable electronics and thereby pave the way for facile in vivo applications of injectable mesh electronics as a general and powerful tool for long-term mapping and modulation of brain activity in fundamental neuroscience through therapeutic biomedical studies. PMID:26317328

  16. 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

  17. Measure for Measure: Calibrating Ten Commonly Used Calibration Scores

    ERIC Educational Resources Information Center

    Schraw, Gregory; Kuch, Fred; Gutierrez, Antonio P.

    2013-01-01

    This study examined the dimensionality of 10 different calibration measures using confirmatory factor analysis (CFA). The 10 measures were representative of five interpretative families of measures used to assess monitoring accuracy based on a 2 (performance) x 2 (monitoring judgment) contingency table. We computed scores for each of the measures…

  18. Photometer calibration error using extended standard sources

    NASA Technical Reports Server (NTRS)

    Torr, M. R.; Hays, P. B.; Kennedy, B. C.; Torr, D. G.

    1976-01-01

    As part of a project to compare measurements of the night airglow made by the visible airglow experiment on the Atmospheric Explorer-C satellite, the standard light sources of several airglow observatories were compared with the standard source used in the absolute calibration of the satellite photometer. In the course of the comparison, it has been found that serious calibration errors (up to a factor of two) can arise when a calibration source with a reflecting surface is placed close to an interference filter. For reliable absolute calibration, the source should be located at a distance of at least five filter radii from the interference filter.

  19. Calibration procedures for standard gas leaks

    NASA Astrophysics Data System (ADS)

    Mehrhoff, T. K.; Mason, T. M.

    1981-12-01

    Calibration procedures for equipment used in measuring flow rates of standardized gas leaks using a mass spectrometer are discussed. The calibration involves measurements of temperature, time, pressure and volume. The mass spectrometer is calibrated with a calibrated micromanometer and pure gas. The micromanometer is calibrated using a volume expansion method and a quartz fiber manometer in the torr range. Apparent volumes in the mass spectrometer inlet systems are calibrated using a quartz fiber manometer. Error analysis is made by using the partial derivative method and the square root of the sum of squares method. The following error contributions were determined: volume +-0.6% temperature +-3.6% (helium only), time +-0.4%, pressure +-4.6%. For helium diffusion leaks an additional error 0.6% was determined as the contribution for alpha the temperature correction factor.

  20. 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.

  1. Individual and socio-environmental factors associated with unsafe injection practices among young adult injection drug users in San Diego

    PubMed Central

    Muñoz, Fátima; Burgos, José Luis; Cuevas-Mota, Jazmine; Teshale, Eyasu; Garfein, Richard S.

    2014-01-01

    Unsafe injection practices significantly increase the risk of hepatitis C virus and human immunodeficiency virus (HIV) infection among injection drug users (IDUs). We examined individual and socio-environmental factors associated with unsafe injection practices in young adult IDUs in San Diego, California. Of 494 IDUs, 46.9% reported receptive syringe sharing and 68.8% sharing drug preparation paraphernalia in the last 3 months. Unsafe injection practices were associated with increased odds of having friends who injected drugs with used syringes, injecting with friends, sexual partners, and injecting heroin. Perceived high susceptibility to HIV and perceived barriers to obtaining sterile syringes were associated with increased odds of receptive syringe sharing, but not with sharing injection paraphernalia. Over half IDUs reported unsafe injection practices, and our results suggest that personal relationships might influence IDUs’ perceptions that dictate behavior. Integrated interventions addressing individual and socio-environmental factors are needed to promote safe injection practices in this population. PMID:24920342

  2. 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.

  3. NIST's New 3D Airspeed Calibration Rig Addresses Turbulent Flow

    E-print Network

    #12;S-Probe, (used in EPA protocol 2) Calibration Factor is a Function of 4 variables 1. Air speed 2.84 (literature shows small, linear dependence on air speed) 11 #12;EPA Method 2: S-Probe Calibration Calibration 20o Recirculation Zone Flow 19 #12;Modify wind tunnel: add Grid to Generate Turbulence #12;Measure

  4. 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.

  5. Place of Residence Moderates the Relationship Between Emotional Closeness and Syringe Sharing Among Injection Drug Using Clients of Sex Workers in the US-Mexico Border Region.

    PubMed

    Wagner, Karla D; Pitpitan, Eileen V; Valente, Thomas W; Strathdee, Steffanie A; Rusch, Melanie; Magis-Rodriguez, Carlos; Chavarin, Claudia V; Patterson, Thomas L

    2015-06-01

    Injection drug-using men from the US and Mexico who purchase sex in Tijuana, Mexico are at risk for transmitting HIV to their contacts in both countries via syringe sharing. We used social network methods to understand whether place of residence (US vs. Mexico) moderated the effect of emotional closeness on syringe sharing. We interviewed 199 drug-using men who reported paying/trading for sex in Tijuana, Mexico using an epidemiological and social network survey and collected samples for HIV/STI testing. Seventy-two men reported using injection drugs with 272 network contacts. Emotional closeness was strongly associated with syringe sharing in relationship where the partner lives in the US, while the relationship between emotional closeness and syringe sharing was considerably less strong in dyads where the partner lives in Mexico. Efforts to reduce HIV risk behaviors in emotionally close relationships are needed, and could benefit from tailoring to the environmental context of the relationship. PMID:25613593

  6. Generalized synthesis of metal phosphide nanorods via thermal decomposition of continuously delivered metal-phosphine complexes using a syringe pump.

    PubMed

    Park, Jongnam; Koo, Bonil; Yoon, Ki Youl; Hwang, Yosun; Kang, Misun; Park, Je-Geun; Hyeon, Taeghwan

    2005-06-15

    We synthesized uniform-sized nanorods of transition metal phosphides from the thermal decomposition of continuously delivered metal-phosphine complexes using a syringe pump. MnP nanorods with dimensions of 8 nm x 16 nm and 6 nm x 22 nm sized were synthesized by the thermal decomposition of Mn-TOP complex, which was prepared from the reaction of Mn(2)(CO)(10) and tri-n-octylphosphine (TOP), using a syringe pump with constant injection rates of 10 and 20 mL/h, respectively. When Co-TOP complex, which was prepared from the reaction of cobalt acetylacetonate and TOP, was reacted in a mixture solvent composed of octyl ether and hexadecylamine at 300 degrees C using a syringe pump, uniform 2.5 nm x 20 nm sized Co(2)P nanorods were generated. When cobaltocene was employed as a precursor, uniform Co(2)P nanorods with 5 nm x 15 nm were obtained. When Fe-TOP complex was added to trioctylphosphine oxide (TOPO) at 360 degrees C using a syringe pump and then allowed to age at 360 degrees C for 30 min, uniform-sized FeP nanorods with an average dimension of 12 nm x 500 nm were produced. Nickel phosphide (Ni(2)P) nanorods with 4 nm x 8 nm were synthesized successfully by thermally decomposing the Ni-TOP complex, which was synthesized by reacting acetylacetonate [Ni(acac)(2)] and TOP. We measured the magnetic properties of these nanorods, and some of the nanorods exhibited different magnetic characteristics compared to the bulk counterparts. PMID:15941277

  7. 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

  8. A portable multi-syringe flow system for spectrofluorimetric determination of iodide in seawater.

    PubMed

    Frizzarin, Rejane M; Aguado, Enrique; Portugal, Lindomar A; Moreno, Daniel; Estela, José M; Rocha, Fábio R P; Cerdà, Victor

    2015-11-01

    A miniaturized analyzer encompassing a poly(methyl methacrylate) chip with integrated spectrofluorimetric detection and solutions propelling by a multi-syringe module is proposed. Iodide was determined through its catalytic effect on the reaction between Ce(IV) and As(III). Matrix isopotential synchronous fluorescence was explored to set the excitation and emission wavelengths. A two-level full factorial design allowed to evaluate the significance of variables (Ce(IV), As(III) and H2SO4 concentrations) and their interaction effects in the experimental domain. A Doehlert Matrix was applied to identify the critical values. The optimized procedure showed a linear response from 1 to 100?gL(-1) (S=53.7+2.61C, in which S is the net fluorescence and C is iodide concentration in ?gL(-1)). Detection limit, coefficient of variation (n=6) and sampling rate were estimated at 0.3 ?gL(-1), 0.8% and 20h(-1), respectively. Recoveries within 90-117% were estimated for iodide spiked to seawater samples. The proposed procedure stands out because of the portability, robustness, and simplicity for in-field analysis of iodide in seawater. PMID:26452941

  9. Direct Evidence of Egestion and Salivation of Xylella fastidiosa Suggests Sharpshooters Can Be "Flying Syringes".

    PubMed

    Backus, Elaine A; Shugart, Holly J; Rogers, Elizabeth E; Morgan, J Kent; Shatters, Robert

    2015-05-01

    Xylella fastidiosa is unique among insect-transmitted plant pathogens because it is propagative but noncirculative, adhering to and multiplying on the cuticular lining of the anterior foregut. Any inoculation mechanism for X. fastidiosa must explain how bacterial cells exit the vector's stylets via the food canal and directly enter the plant. A combined egestion-salivation mechanism has been proposed to explain these unique features. Egestion is the putative outward flow of fluid from the foregut via hypothesized bidirectional pumping of the cibarium. The present study traced green fluorescent protein-expressing X. fastidiosa or fluorescent nanoparticles acquired from artificial diets by glassy-winged sharpshooters, Homalodisca vitripennis, as they were egested into simultaneously secreted saliva. X. fastidiosa or nanoparticles were shown to mix with gelling saliva to form fluorescent deposits and salivary sheaths on artificial diets, providing the first direct, conclusive evidence of egestion by any hemipteran insect. Therefore, the present results strongly support an egestion-salivation mechanism of X. fastidiosa inoculation. Results also support that a column of fluid is transiently held in the foregut without being swallowed. Evidence also supports (but does not definitively prove) that bacteria were suspended in the column of fluid during the vector's transit from diet to diet, and were egested with the held fluid. Thus, we hypothesize that sharpshooters could be true "flying syringes," especially when inoculation occurs very soon after uptake of bacteria, suggesting the new paradigm of a nonpersistent X. fastidiosa transmission mechanism. PMID:26020829

  10. Antimicrobial activity of syringic acid against Cronobacter sakazakii and its effect on cell membrane.

    PubMed

    Shi, Chao; Sun, Yi; Zheng, Zhiwei; Zhang, Xiaorong; Song, Kaikuo; Jia, Zhenyu; Chen, Yifei; Yang, Miaochun; Liu, Xin; Dong, Rui; Xia, Xiaodong

    2016-04-15

    Syringic acid (SA) has been reported to exhibit antibacterial ability against various microorganisms, but little work has been done on its effect on Cronobacter sakazakii. In this study, minimum inhibitory concentrations (MICs) of SA against various C. sakazakii strains were determined. Moreover, changes in intracellular ATP concentration, intracellular pH (pHin), membrane potential and membrane integrity were measured to evaluate the influence of SA on cell membrane. Finally, field emission scanning electron microscope (FESEM) was used to assess the morphological changes of bacterial cells caused by SA. It was shown that the MICs of SA against all tested C. sakazakii strains were 5mg/mL. SA retarded bacterial growth, and caused cell membrane dysfunction, which was evidenced by intracellular ATP concentration decrease, pHin reduction, cell membrane hyperpolarization and changes in cellular morphology. These findings indicated that SA has potential to be developed as a natural preservative to control C. sakazakii in foods associated with this pathogen and prevent related infections. PMID:26616929

  11. Syringe filtration methods for examining dissolved and colloidal trace element distributions in remote field locations

    NASA Technical Reports Server (NTRS)

    Shiller, Alan M.

    2003-01-01

    It is well-established that sampling and sample processing can easily introduce contamination into dissolved trace element samples if precautions are not taken. However, work in remote locations sometimes precludes bringing bulky clean lab equipment into the field and likewise may make timely transport of samples to the lab for processing impossible. Straightforward syringe filtration methods are described here for collecting small quantities (15 mL) of 0.45- and 0.02-microm filtered river water in an uncontaminated manner. These filtration methods take advantage of recent advances in analytical capabilities that require only small amounts of waterfor analysis of a suite of dissolved trace elements. Filter clogging and solute rejection artifacts appear to be minimal, although some adsorption of metals and organics does affect the first approximately 10 mL of water passing through the filters. Overall the methods are clean, easy to use, and provide reproducible representations of the dissolved and colloidal fractions of trace elements in river waters. Furthermore, sample processing materials can be prepared well in advance in a clean lab and transported cleanly and compactly to the field. Application of these methods is illustrated with data from remote locations in the Rocky Mountains and along the Yukon River. Evidence from field flow fractionation suggests that the 0.02-microm filters may provide a practical cutoff to distinguish metals associated with small inorganic and organic complexes from those associated with silicate and oxide colloids.

  12. 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

  13. 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.

  14. 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, David 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.

  15. 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....

  16. Automated Camera Calibration

    NASA Technical Reports Server (NTRS)

    Chen, Siqi; Cheng, Yang; Willson, Reg

    2006-01-01

    Automated Camera Calibration (ACAL) is a computer program that automates the generation of calibration data for camera models used in machine vision systems. Machine vision camera models describe the mapping between points in three-dimensional (3D) space in front of the camera and the corresponding points in two-dimensional (2D) space in the camera s image. Calibrating a camera model requires a set of calibration data containing known 3D-to-2D point correspondences for the given camera system. Generating calibration data typically involves taking images of a calibration target where the 3D locations of the target s fiducial marks are known, and then measuring the 2D locations of the fiducial marks in the images. ACAL automates the analysis of calibration target images and greatly speeds the overall calibration process.

  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. Methods for routine calibration of brachytherapy sources.

    PubMed

    Williamson, J F; Khan, F M; Sharma, S C; Fullerton, G D

    1982-02-01

    Two types of routine geometry calibrators, the nuclear medicine dose calibrator and a Lucite jig holding a 30-ml external beam ion chamber with the source in a rigid geometry, were compared with open-air measurements for 137Cs, 192Ir, and 226Ra brachytherapy sources. The proximity of scattering surfaces in the second apparatus resulted in significant distortion of the buildup effect and deviation from the inverse square law (5% to 15%). For the dose calibrator, the response/Roentgen was found to be dependent not only on source energy, but on source capsule thickness as well. Approximately one half of the observed variation (27%) in calibration factors was accounted for by differences in filtration among sources. A mathematical logarithm that corrects for these geometric and filtration effects is presented. In addition, the activity assay procedure provided by the manufacturer of the dose calibrator is shown to be unsuitable for brachytherapy sources. Steps to overcome these problems are discussed. PMID:7054845

  19. Residual gas analyzer calibration

    NASA Technical Reports Server (NTRS)

    Lilienkamp, R. H.

    1972-01-01

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

  20. 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

  1. 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

  2. On-line lab-in-syringe cloud point extraction for the spectrophotometric determination of antimony.

    PubMed

    Frizzarin, Rejane M; Portugal, Lindomar A; Estela, José M; Rocha, Fábio R P; Cerdà, Victor

    2016-02-01

    Most of the procedures for antimony determination require time-consuming sample preparation (e.g. liquid-liquid extraction with organic solvents), which are harmful to the environment. Because of the high antimony toxicity, a rapid, sensitive and greener procedure for its determination becomes necessary. The goal of this work was to develop an analytical procedure exploiting for the first time the cloud point extraction on a lab-in-syringe flow system aiming at the spectrophotometric determination of antimony. The procedure was based on formation of an ion-pair between the antimony-iodide complex and H(+) followed by extraction with Triton X-114. The factorial design showed that the concentrations of ascorbic acid, H2SO4 and Triton X-114, as well as second and third order interactions were significant at the 95% confidence level. A Box-Behnken design was applied to obtain the response surfaces and to identify the critical values. System is robust at the 95% confidence level. A linear response was observed from 5 to 50µgL(-1), described by the equation A=0.137+0.050CSb (r=0.998). The detection limit (99.7% confidence level), the coefficient of variation (n=5; 15µgL(-1)) and the sampling rate was estimated at 1.8µgL(-1), 1.6% and 16h(-1), respectively. The procedure allows quantification of antimony in the concentrations established by environmental legislation (6µgL(-1)) and it was successfully applied to the determination of antimony in freshwater samples and antileishmanial drugs, yielding results in agreement with those obtained by HGFAAS at the 95% confidence level. PMID:26653503

  3. 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.

  4. 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.

  5. Automated in-syringe single-drop head-space micro-extraction applied to the determination of ethanol in wine samples.

    PubMed

    Srámková, Ivana; Horstkotte, Burkhard; Solich, Petr; Sklená?ová, Hana

    2014-05-30

    A novel approach of head-space single-drop micro-extraction applied to the determination of ethanol in wine is presented. For the first time, the syringe of an automated syringe pump was used as an extraction chamber of adaptable size for a volatile analyte. This approach enabled to apply negative pressure during the enrichment step, which favored the evaporation of the analyte. Placing a slowly spinning magnetic stirring bar inside the syringe, effective syringe cleaning as well as mixing of the sample with buffer solution to suppress the interference of acetic acid was achieved. Ethanol determination was based on the reduction of a single drop of 3mmol L(-1) potassium dichromate dissolved in 8mol L(-1) sulfuric acid. The drop was positioned in the syringe inlet in the head-space above the sample with posterior spectrophotometric quantification. The entire procedure was carried out automatically using a simple sequential injection analyzer system. One analysis required less than 5min including the washing step. A limit of detection of 0.025% (v/v) of ethanol and an average repeatability of less than 5.0% RSD were achieved. The consumption of dichromate reagent, buffer, and sample per analysis were only 20?L, 200?L, and 1mL, respectively. The results of real samples analysis did not differ significantly from those obtained with the references gas chromatography method. PMID:24845815

  6. The COS Calibration Pipeline

    NASA Astrophysics Data System (ADS)

    Hodge, Philip E.; Keyes, C.; Kaiser, M.

    2007-12-01

    The COS calibration pipeline (CALCOS) includes three main components: basic calibration, wavelength calibration, and spectral extraction. Calibration of modes using the far ultraviolet (FUV) and near ultraviolet (NUV) detectors share a common structure, although the individual reference files differ and there are some additional steps for the FUV channel. The pipeline is designed to calibrate data acquired in either ACCUM or time-tag mode. The basic calibration includes pulse-height filtering and geometric correction for FUV, and flat-field, deadtime, and Doppler correction for both detectors. Wavelength calibration can be done either by using separate lamp exposures or by taking several short lamp exposures concurrently with a science exposure. For time-tag data, the latter mode ("tagflash") will allow better correction of potential drift of the spectrum on the detector. One-dimensional spectra will be extracted and saved in a FITS binary table. Separate columns will be used for the flux-calibrated spectrum, error estimate, and the associated wavelengths. CALCOS is written in Python, with some functions in C. It is similar in style to other HST pipeline code in that it uses an association table to specify which files to be included, and the calibration steps to be performed and the reference files to use are specified by header keywords. Currently, in conjunction with the Instrument Definition Team (led by J. Green), the ground-based reference files are being refined, delivered, and tested with the pipeline.

  7. Laser interferometer calibration station

    NASA Astrophysics Data System (ADS)

    Campolmi, R. W.; Krupski, S. J.

    1981-10-01

    The laser interferometer is a versatile tool, used for calibration over both long and short distances. It is considered traceable to the National Bureau of Standards. The system developed under this project was to be capable of providing for the calibration of many types of small linear measurement devices. The logistics of the original concept of one location for calibration of all mics, calipers, etc. at a large manufacturing facility proved unworkable. The equipment was instead used for the calibration of the large machines used to manufacture cannon tubes.

  8. 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.

  9. Cumulative sum quality control for calibrated breast density measurements

    SciTech Connect

    Heine, John J.; Cao Ke; Beam, Craig

    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.

  10. 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.

  11. CALIBRATION T. David Reed

    E-print Network

    for the calibration distance based on transplanter row spacing, operating at the desired speed. Collect setter water to travel according to nozzle spacing from the chart below. 2. Record the travel time over the calibration distance with equipment attached and operating in appropriate field conditions at the desired speed. 3

  12. Automatic Calibration Systems

    NASA Technical Reports Server (NTRS)

    Ferris, A. T.; Edwards, S. F.; Stewart, W. F.; Mason, D. R. J.; Finley, T. D.; Williams, H. E.

    1982-01-01

    A continuous requirement exists for calibration and environmental testing of instruments in use at multitude of test facilities at Langley Research Center. Brief summarizes several automated systems available for calibration of research instruments to include: six-component balance, multimeter, amplifier, pyrometer, voltage-controlled oscillator, pressure transducer and accelerometer.

  13. 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

  14. 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.

  15. Calibration Revisited Jan Kodovsk

    E-print Network

    Fridrich, Jessica

    ]. Since then, it became an essential part of many feature-based blind and targeted ste- ganalyzers in JPEG the sample statistics of the models as features. Although calibration was originally introduced for the JPEG-to-image variations. While this is in principle correct, this beneficial effect of calibration does not have

  16. Marinelli beaker calibration

    SciTech Connect

    Zimmer, W.H.

    1980-01-01

    The calibration of gamma spectroscopy detectors for analysis of samples in Marinelli beakers is discussed with regard to what constitutes a calibration standard and difference from a point source. Sorption effects are energy dependent and can cause errors of 20 percent or more. True coincidence summing effects can totally misalign detector efficiency, depending on the nuclides contained in the standard.

  17. 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.

  18. Effect of liposomes on rheological and syringeability properties of hyaluronic acid hydrogels intended for local injection of drugs.

    PubMed

    El Kechai, Naila; Bochot, Amélie; Huang, Nicolas; Nguyen, Yann; Ferrary, Evelyne; Agnely, Florence

    2015-06-20

    The aim of this work was to thoroughly study the effect of liposomes on the rheological and the syringeability properties of hyaluronic acid (HA) hydrogels intended for the local administration of drugs by injection. Whatever the characteristics of the liposomes added (neutral, positively or negatively charged, with a corona of polyethylene glycol chains, size), the viscosity and the elasticity of HA gels increased in a lipid concentration-dependent manner. Indeed, liposomes strengthened the network formed by HA chains due to their interactions with this polymer. The nature and the resulting effects of these interactions depended on liposome composition and concentration. The highest viscosity and elasticity were observed with liposomes covered by polyethylene glycol chains while neutral liposomes displayed the lowest effect. Despite their high viscosity at rest, all the formulations remained easily injectable through needles commonly used for local injections thanks to the shear-thinning behavior of HA gels. The present study demonstrates that rheological and syringeability tests are both necessary to elucidate the behavior of such systems during and post injection. In conclusion, HA liposomal gels appear to be a promising and versatile formulation platform for a wide range of applications in local drug delivery when an injection is required. PMID:25882015

  19. Syringe test (modified larval immersion test): a new bioassay for testing acaricidal activity of plant extracts against Rhipicephalus microplus.

    PubMed

    Sindhu, Zia-ud-Din; Jonsson, Nicholas N; Iqbal, Zafar

    2012-09-10

    We report a new bioassay "syringe test" (modified larval immersion test) for in vitro evaluation of acaricidal activity of crude plant extracts. Prepared syringes, containing eggs of tick, were incubated until 14 d after hatching of eggs, when the bioassay was performed on the larvae. Lethal concentrations for 50% of larvae (LC(50)), LC(90) and LC(99) values were calculated for each tested product. 95% confidence intervals for LC(50) were very narrow, indicating a high degree of repeatability for the new bioassay on larvae of R. microplus. Bioassays were applied to six crude aqueous-methanol extracts from five plants (Acacia nilotica, Buxus papillosa, Fumaria parviflora, Juniperus excelsa, and Operculina turpethum), of which three showed discernible effects. Twenty-four hours post exposure, LC(99) values were 11.9% (w/v) for F. parviflora, 20.8% (w/v) and 29.2% (w/v) for B. papillosa and A. nilotica, respectively. After six days of exposure these values were; 9.1% (w/v), 9.2% (w/v) and 15.5 (w/v) for F. parviflora, A. nilotica and B. papillosa, respectively. PMID:22516644

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

    PubMed

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

    2007-11-01

    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

  1. Sandia WIPP calibration traceability

    SciTech Connect

    Schuhen, M.D.; Dean, T.A.

    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.

  2. Calibration of neutron-sensitive devices

    NASA Astrophysics Data System (ADS)

    Gressier, V.; Taylor, G. C.

    2011-12-01

    The calibration of a neutron-sensitive device can range from a simple calibration factor at a single energy or energy distribution to a full response characterization over the entire energy range to which the device is sensitive. As the responses of neutron-sensitive devices and the fluence-to-dose-equivalent conversion coefficients can vary with neutron energy and incident angle, both simulation and experiments in standard neutron fields are required. Although several ISO standards present calibration principles in general and detailed discussion on many specific areas, there are certain omissions and limitations that this paper intends to highlight, along with some new recommendations derived from the recent literature, mainly focused on the effective centre, corrections for geometry and neutron scattering, as well as the problem of calibrating in terms of personal dose equivalent.

  3. 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.

  4. Behavioral and Demographic Factors Associated with Acute and Chronic Wounds among Clients of an Injection Drug Syringe Exchange Program

    E-print Network

    on thigh Abscess on leg Cooking heroin for injection NEP van at Fremont & Riggs Used needles after exchange/frequency % n/N Years injecting drugs 9-14 yrs 15.6 17/109 15 yrs 57.8 63/109 Heroin Never 2.8 3

  5. Calibration of Gamma-Ray Brachytherapy Sources.

    NASA Astrophysics Data System (ADS)

    Williamson, Jeffrey Ford

    The intensity of ('137)Cs, ('192)Ir, and ('226)Ra brachytherapy sources is currently specified in terms of exposure rate as measured in a scatter-free geometry utilizing a long source to detector distance. For reasons of convenience, such sources are routinely calibrated using some type of re-entrant ionization chamber such as the dose calibrator investigated in this thesis. Although it is known that the calibrator response (reading/unit exposure rate) varies significantly from one source to another, this phenomenon is usually attributed to the intrinsic energy response of the instrument. However, investigation by empirical, analytic, and Monte Carlo methodologies shows that source filtration depresses dose calibrator response in the range of 2% for ('137)Cs (0.65mm stainless steel filtration) to 10.5% for a platinum-clad ('192)Ir seed, relative to an unfiltered point source having the same (gamma)-ray spectrum as the given filtered source. Only the Monte Carlo simulation accurately predicted the filtration effect. The analytic model, derived from the Sievert integral, underestimated the effect by 1 to 3.5%. These results demonstrate that an exposure calibrated standard source is required to establish calibrator response for each clinically used filtration as well as (gamma)-ray spectrum. A more general consequence of this analysis is that the accuracy of computed exposure rate distributions for filtered sources significantly improves, given uncertainties in filtration corrections and spectroscopic data, when source intensity is measured in terms of exposure rate rather than absolute activity. The dosimetric error introduced by the Sievert approximation, relative to the more rigorous Monte Carlo results, is reduced by a factor of 2-3 when exposure rate, rather than activity calibration, is adopted. Similarly, exposure calibration is shown to reduce the sensitivity of computed exposure rate to spectroscopic uncertainty by a factor of 75-100.

  6. Unassisted 3D camera calibration

    NASA Astrophysics Data System (ADS)

    Atanassov, Kalin; Ramachandra, Vikas; Nash, James; Goma, Sergio R.

    2012-03-01

    With the rapid growth of 3D technology, 3D image capture has become a critical part of the 3D feature set on mobile phones. 3D image quality is affected by the scene geometry as well as on-the-device processing. An automatic 3D system usually assumes known camera poses accomplished by factory calibration using a special chart. In real life settings, pose parameters estimated by factory calibration can be negatively impacted by movements of the lens barrel due to shaking, focusing, or camera drop. If any of these factors displaces the optical axes of either or both cameras, vertical disparity might exceed the maximum tolerable margin and the 3D user may experience eye strain or headaches. To make 3D capture more practical, one needs to consider unassisted (on arbitrary scenes) calibration. In this paper, we propose an algorithm that relies on detection and matching of keypoints between left and right images. Frames containing erroneous matches, along with frames with insufficiently rich keypoint constellations, are detected and discarded. Roll, pitch yaw , and scale differences between left and right frames are then estimated. The algorithm performance is evaluated in terms of the remaining vertical disparity as compared to the maximum tolerable vertical disparity.

  7. 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 \

  8. 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.

  9. 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.

  10. Compact radiometric microwave calibrator

    SciTech Connect

    Fixsen, D. J.; Wollack, E. J.; Kogut, A.; Limon, M.; Mirel, P.; Singal, J.; Fixsen, S. M.

    2006-06-15

    The calibration methods for the ARCADE II instrument are described and the accuracy estimated. The Steelcast coated aluminum cones which comprise the calibrator have a low reflection while maintaining 94% of the absorber volume within 5 mK of the base temperature (modeled). The calibrator demonstrates an absorber with the active part less than one wavelength thick and only marginally larger than the mouth of the largest horn and yet black (less than -40 dB or 0.01% reflection) over five octaves in frequency.

  11. Calibrated Properties Model

    SciTech Connect

    C.F. Ahlers, H.H. Liu

    2001-12-18

    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 (CRWMS M&O 1999c). 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.

  12. 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.

  13. 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.

  14. TOF-SIMS: accurate mass scale calibration.

    PubMed

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

    2006-04-01

    A study is presented of the factors affecting the calibration of the mass scale in time-of-flight secondary ion mass spectrometry (TOF-SIMS). At the present time, TOF-SIMS analysts using local calibration procedures achieve a rather poor relative mass accuracy of only 150 ppm for large molecules (647 u) whereas for smaller fragments of <200 u this figure only improves to 60 ppm. The instrumental stability is 1 ppm and better than 10 ppm is necessary for unique identification of species. The above experimental uncertainty can lead to unnecessary confusion where peaks are wrongly identified or peaks are ambiguously assigned. Here we study, in detail, the instrumental parameters of a popular single stage reflection TOF-SIMS instrument with ion trajectory calculations using SIMION. The effect of the ion kinetic energy, emission angle, and other instrumental operating parameters on the measured peak position are determined. This shows clearly why molecular and atomic ions have different relative peak positions and the need for an aperture to restrict ions at large emission angles. These data provide the basis for a coherent procedure for optimizing the settings for accurate mass calibration and rules by which calibrations for inorganics and organics may be incorporated. This leads to a new generic set of ions for mass calibration that improves the mass accuracy in our interlaboratory study by a factor of 5. A calibration protocol is developed, which gives a relative mass accuracy of better than 10 ppm for masses up to 140 u. The effects of extrapolation beyond the calibration range are discussed and a recommended procedure is given to ensure that accurate mass is achieved within a selectable uncertainty for large molecules. Additionally, we can alternatively operate our instrument in a regime with good energy discrimination (i.e., poor energy compensation) to study the fragmented energies of molecules. This leads to data that support previous concepts developed in G-SIMS. PMID:16503150

  15. Assessment of an in vitro whole cigarette smoke exposure system: The Borgwaldt RM20S 8-syringe smoking machine

    PubMed Central

    2011-01-01

    Background There have been many recent developments of in vitro cigarette smoke systems closely replicating in vivo exposures. The Borgwaldt RM20S smoking machine (RM20S) enables the serial dilution and delivery of cigarette smoke to exposure chambers for in vitro analyses. In this study we have demonstrated reliability and robustness testing of the RM20S in delivering smoke to in vitro cultures using an in-house designed whole smoke exposure chamber. Results The syringe precision and accuracy of smoke dose generated by the RM20S was assessed using a methane gas standard and resulted in a repeatability error of ?9%. Differential electrical mobility particle spectrometry (DMS) measured smoke particles generated from reference 3R4F cigarettes at points along the RM20S. 53% ± 5.9% of particles by mass reached the chamber, the remainder deposited in the syringe or connecting tubing and ~16% deposited in the chamber. Spectrofluorometric quantification of particle deposition within chambers indicated a positive correlation between smoke concentration and particle deposition. In vitro air-liquid interface (ALI) cultures (H292 lung epithelial cells), exposed to whole smoke (1:60 dilution (smoke:air, equivalent to ~5 ?g/cm2)) demonstrated uniform smoke delivery within the chamber. Conclusions These results suggest this smoke exposure system is a reliable and repeatable method of generating and exposing ALI in vitro cultures to cigarette smoke. This system will enable the evaluation of future tobacco products and individual components of cigarette smoke and may be used as an alternative in vitro tool for evaluating other aerosols and gaseous mixtures such as air pollutants, inhaled pharmaceuticals and cosmetics. PMID:21867559

  16. 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

  17. Comparison of site calibration and cross calibration of Gao Fen (GF)-1 Wide Field of View (WFV)

    NASA Astrophysics Data System (ADS)

    Liu, Li; Xu, Wen; Lu, Shuning; Fu, Qiaoyan; Pan, Zhiqiang; Shi, Tingting

    2015-10-01

    The Wide Field of View (WFV) is one of the key instruments for China's high resolution earth observing system, operating on the Gao Fen-1 (GF-1) satellite which was launched on April 26, 2013. WFV has 4 typical reflective solar bands from 0.45-0.89 ?m with 16m nadir spatial resolution. Because of GF-1's lacking in onboard calibrators, on-orbit radiometric calibration is mainly relies on site calibration. The reflectance-based method of site calibration has been used for the absolute radiometric calibration of the GF-1 WFV on June 26th, 2013 and August 3rd, 2014. The reflectance-based method relies on ground-based measurements of the surface reflectance and atmospheric conditions at Dunhuang test site nearly coincident with the imaging of the test site by the WFV. Site calibration is a time consuming and hard sledding method, which is also difficult to reveal or adequately correct for the deficiency of instrument calibration by its own calibration subsystem. Cross-calibration can be a powerful method to remedy the insufficient of the site calibration. Terra Moderate Resolution Imaging Spectroradiometer (MODIS) with its high accuracy onboard calibration system has been selected as reference sensor. Cross calibration between GF-1/WFV and Terra/MODIS are based on the near-simultaneous and cloud-free image pairs over Dunhuang test site on the same day with site calibration. Spectral band adjustment factors (SBAF) for the cross calibration are determined by SRF, solar zenith and azimuth angle, sensors' zenith and azimuth angle and a typical reflectance spectrum over the Dunhuang test site obtained by in-situ measurements. The percentage difference between the site calibrations is within 5% which reflects that the GF-1/WFV is stable after the launch and the reflectance-based method itself is reliable. The comparison of site calibration and cross calibration shows that site calibration has higher accuracy than the cross calibration, the cross calibration is affected by the SBAF.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. Sprayer Calibration for Turfgrass 

    E-print Network

    Taylor, Gene R.; Abernathy, Scott

    1999-12-08

    calibration process. There are three main formulas that calculate GPA (gallons per acre), GPM (gallons per minute), and MPH (miles per hour). Use each of these formulas to determine and or change the output of the sprayer over a given area (usually per acre... in inches. MILES per hour formula Before making any of the other calibration calculations, determine the actual ground speed of the sprayer in miles per hour (MPH). 1. Measure out 200 feet of terrain in the area to be sprayed and mark it visibly. 2. Fill...

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. A randomized clinical trial in adults and newborns in South Africa to compare the safety and immunogenicity of bacille Calmette-Guérin (BCG) vaccine administration via a disposable-syringe jet injector to conventional technique with needle and syringe

    PubMed Central

    Geldenhuys, Hennie D.; Mearns, Helen; Foster, Jennifer; Saxon, Eugene; Kagina, Benjamin; Saganic, Laura; Jarrahian, Courtney; Tameris, Michele D.; Dintwe, One B.; Van Rooyen, Michele; Luabeya, Kany-Kany A.; Hussey, Gregory; Scriba, Thomas J.; Hatherill, Mark; Zehrung, Darin

    2015-01-01

    Introduction Intradermal bacille Calmette-Guérin (BCG) vaccination by needle-free, disposable-syringe jet injectors (DSJI) is an alternative to the Mantoux method using needle and syringe (NS). We compared the safety and immunogenicity of BCG administration via the DSJI and NS techniques in adults and newborn infants at the South African Tuberculosis Vaccine Initiative (SATVI) research site in South Africa. Method Thirty adults and 66 newborn infants were randomized 1:1 to receive intradermal BCG vaccine (0.1 mL in adults; 0.05 mL in infants) via DSJI or NS. Wheal diameter (mm) and skin fluid deposition at the site of injection (SOI) were measured immediately post-vaccination. Adverse events and SOI reactogenicity data were collected 30 min and 1, 2, 4, and 12 weeks after vaccination for adults and at 30 min and 4, 10, and 14 weeks for infants. Blood was collected in infants at 10 and 14 weeks to assess BCG-specific T-cell immune responses. Results More infant BCG vaccinations by DSJI deposited >5 ?L fluid on the skin surface, compared to NS (49% versus 9%, p = 0.001). However, all 12 infant vaccinations that did not produce any SOI wheal occurred in the NS group (36%, p < 0.001). Median wheal diameter, in participants for which an SOI wheal formed, did not differ significantly between groups in infants (combined 3.0 mm IQR 2.0 to 4.0, p = 0.59) or in adults (combined 9.0 mm IQR 7.0 to 10.0, p = 0.13). Adverse events were similar between study arms. Proportion of participants with BCG scars after three months did not differ in adults (combined 97%, p = 0.67) or infants (combined 62%, p = 0.13). Frequencies of BCG-specific clusters of differentiation 4 (CD4) and clusters of differentiation 8 (CD8) T-cells co-expressing IFN-?, TNF-?, IL-2, and/or IL-17 were not different in the DSJI and NS groups. Conclusion BCG vaccination of newborn infants via DSJI was more likely to deliver an appropriate intradermal wheal at the SOI as compared to NS, despite leaving more fluid on the surface of the skin. Safety, reactogenicity, and antigen-specific T-cell immune responses did not differ between DSJI and NS techniques. PMID:25862299

  9. OARE flight maneuvers and calibration measurements on STS-58

    NASA Technical Reports Server (NTRS)

    Blanchard, Robert C.; Nicholson, John Y.; Ritter, James R.; Larman, Kevin T.

    1994-01-01

    The Orbital Acceleration Research Experiment (OARE), which has flown on STS-40, STS-50, and STS-58, contains a three axis accelerometer with a single, nonpendulous, electrostatically suspended proofmass which can resolve accelerations to the nano-g level. The experiment also contains a full calibration station to permit in situ bias and scale factor calibration. This on-orbit calibration capability eliminates the large uncertainty of ground-based calibrations encountered with accelerometers flown in the past on the orbiter, thus providing absolute acceleration measurement accuracy heretofore unachievable. This is the first time accelerometer scale factor measurements have been performed on orbit. A detailed analysis of the calibration process is given along with results of the calibration factors from the on-orbit OARE flight measurements on STS-58. In addition, the analysis of OARE flight maneuver data used to validate the scale factor measurements in the sensor's most sensitive range is also presented. Estimates on calibration uncertainties are discussed. This provides bounds on the STS-58 absolute acceleration measurements for future applications.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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.

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

    NASA Astrophysics Data System (ADS)

    Haaland, David M.

    1992-03-01

    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 mid- or near-infrared spectra of the blood. Progress toward the noninvasive determination of glucose levels in diabetics is an ultimate goal of this research.

  18. Calibration procedure for Slocum glider deployed optical instruments.

    PubMed

    Cetini?, Ivona; Toro-Farmer, Gerardo; Ragan, Matthew; Oberg, Carl; Jones, Burton H

    2009-08-31

    Recent developments in the field of the autonomous underwater vehicles allow the wide usage of these platforms as part of scientific experiments, monitoring campaigns and more. The vehicles are often equipped with sensors measuring temperature, conductivity, chlorophyll a fluorescence (Chl a), colored dissolved organic matter (CDOM) fluorescence, phycoerithrin (PE) fluorescence and spectral volume scattering function at 117 degrees, providing users with high resolution, real time data. However, calibration of these instruments can be problematic. Most in situ calibrations are performed by deploying complementary instrument packages or water samplers in the proximity of the glider. Laboratory calibrations of the mounted sensors are difficult due to the placement of the instruments within the body of the vehicle. For the laboratory calibrations of the Slocum glider instruments we developed a small calibration chamber where we can perform precise calibrations of the optical instruments aboard our glider, as well as sensors from other deployment platforms. These procedures enable us to obtain pre- and post-deployment calibrations for optical fluorescence instruments, which may differ due to the biofouling and other physical damage that can occur during long-term glider deployments. We found that biofouling caused significant changes in the calibration scaling factors of fluorescent sensors, suggesting the need for consistent and repetitive calibrations for gliders as proposed in this paper. PMID:19724540

  19. Streak camera time calibration procedures

    NASA Technical Reports Server (NTRS)

    Long, J.; Jackson, I.

    1978-01-01

    Time calibration procedures for streak cameras utilizing a modulated laser beam are described. The time calibration determines a writing rate accuracy of 0.15% with a rotating mirror camera and 0.3% with an image converter camera.

  20. 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

  1. 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

  2. Integrating Health and Prevention Services in Syringe Access Programs: A Strategy to Address Unmet Needs in a High-Risk Population

    PubMed Central

    Storm, Deborah S.; Hoyt, Mary Jo; Dutton, Loretta; Berezny, Linda; Allread, Virginia; Paul, Sindy

    2014-01-01

    Injection drug users are at a high risk for a number of preventable diseases and complications of drug use. This article describes the implementation of a nurse-led health promotion and disease prevention program in New Jersey's syringe access programs. Initially designed to target women as part of a strategy to decrease missed opportunities for perinatal HIV prevention, the program expanded by integrating existing programs and funding streams available through the state health department. The program now offers health and prevention services to both men and women, with 3,488 client visits in 2011. These services extend the reach of state health department programs, such as adult vaccination and hepatitis and tuberculosis screening, which clients would have had to seek out at multiple venues. The integration of prevention, treatment, and health promotion services in syringe access programs reaches a vulnerable and underserved population who otherwise may receive only urgent and episodic care. PMID:24385646

  3. Additional information on the dripper design -Syringe pump: Harvard Apparatus / Modified 702019 LEADSCREW & 1/2 NUT =

    E-print Network

    Lee, Xuhui

    air package dew point -100oC / part 51785 Continuous dripping versus interrupted dripping The Harvard will drop abruptly. When this happens, the isotopic ratio can deviate from the calibration value by up to 10

  4. 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.

  5. Absolute radiometric calibration of Landsat using a pseudo invariant calibration site

    USGS Publications Warehouse

    Helder, D.; Thome, K.J.; Mishra, N.; Chander, G.; Xiong, Xiaoxiong; Angal, A.; Choi, Tae-young

    2013-01-01

    Pseudo invariant calibration sites (PICS) have been used for on-orbit radiometric trending of optical satellite systems for more than 15 years. This approach to vicarious calibration has demonstrated a high degree of reliability and repeatability at the level of 1-3% depending on the site, spectral channel, and imaging geometries. A variety of sensors have used this approach for trending because it is broadly applicable and easy to implement. Models to describe the surface reflectance properties, as well as the intervening atmosphere have also been developed to improve the precision of the method. However, one limiting factor of using PICS is that an absolute calibration capability has not yet been fully developed. Because of this, PICS are primarily limited to providing only long term trending information for individual sensors or cross-calibration opportunities between two sensors. This paper builds an argument that PICS can be used more extensively for absolute calibration. To illustrate this, a simple empirical model is developed for the well-known Libya 4 PICS based on observations by Terra MODIS and EO-1 Hyperion. The model is validated by comparing model predicted top-of-atmosphere reflectance values to actual measurements made by the Landsat ETM+ sensor reflective bands. Following this, an outline is presented to develop a more comprehensive and accurate PICS absolute calibration model that can be Système international d'unités (SI) traceable. These initial concepts suggest that absolute calibration using PICS is possible on a broad scale and can lead to improved on-orbit calibration capabilities for optical satellite sensors.

  6. 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. PMID:25848231

  7. Reduction in HCV Incidence Among Injection Drug Users Attending Needle and Syringe Programs in Australia: A Linkage Study

    PubMed Central

    Wand, Handan; Topp, Libby; Kaldor, John; Maher, Lisa

    2013-01-01

    Objectives. We examined trends in HCV incident infection among injection drug users (IDUs) attending needle and syringe programs (NSPs) in Australia in 1995 to 2010. Methods. We created a passive retrospective cohort of 724 IDUs who tested negative for HCV antibodies by a simple deterministic method linking partial identifiers to find repeat respondents in annual cross-sectional serosurveillance. Results. We identified 180 HCV seroconversions over the study period, for a pooled incidence density of 17.0 per 100 person-years (95% confidence interval [CI]?=?14.68, 19.66). Incidence density declined, from a high of 30.8 per 100 person-years (95% CI?=?21.3, 44.6) in 2003 to a low of 4.0 (95% CI?=?1.3, 12.3) in 2009. Conclusions. A decline in HCV incidence among Australian IDUs attending NSPs coincided with considerable expansion of harm reduction programs and a likely reduction in the number of IDUs, associated with significant changes in drug markets. Our results demonstrate the capacity of repeat cross-sectional serosurveillance to monitor trends in HCV incidence and provide a platform from which to assess the impact of prevention and treatment interventions. PMID:23763399

  8. 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...

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Calibration of hydrometers

    NASA Astrophysics Data System (ADS)

    Lorefice, Salvatore; Malengo, Andrea

    2006-10-01

    After a brief description of the different methods employed in periodic calibration of hydrometers used in most cases to measure the density of liquids in the range between 500 kg m-3 and 2000 kg m-3, particular emphasis is given to the multipoint procedure based on hydrostatic weighing, known as well as Cuckow's method. The features of the calibration apparatus and the procedure used at the INRiM (formerly IMGC-CNR) density laboratory have been considered to assess all relevant contributions involved in the calibration of different kinds of hydrometers. The uncertainty is strongly dependent on the kind of hydrometer; in particular, the results highlight the importance of the density of the reference buoyant liquid, the temperature of calibration and the skill of operator in the reading of the scale in the whole assessment of the uncertainty. It is also interesting to realize that for high-resolution hydrometers (division of 0.1 kg m-3), the uncertainty contribution of the density of the reference liquid is the main source of the total uncertainty, but its importance falls under about 50% for hydrometers with a division of 0.5 kg m-3 and becomes somewhat negligible for hydrometers with a division of 1 kg m-3, for which the reading uncertainty is the predominant part of the total uncertainty. At present the best INRiM result is obtained with commercially available hydrometers having a scale division of 0.1 kg m-3, for which the relative uncertainty is about 12 × 10-6.

  14. Mesoscale hybrid calibration artifact

    DOEpatents

    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.

  15. Introduction Calibrating MISR AOD

    E-print Network

    Paciorek, Chris

    Integrating remote sensing and ground monitoring data to improve estimation of PM2.5 concentrations AOD Calibrating GOES AOD Statistical prediction in space and time Exposure estimation for PM2.5 Statistical prediction in space and time Correspondence of AOD and PM PM2.5, 12/5/2004 1.5 4.5 7.5 10.5 13

  16. NOAA polar satellite calibration: A system description

    NASA Astrophysics Data System (ADS)

    Paris, Cecil A.

    1994-02-01

    The operational processing of polar satellite data has undergone many evolutionary changes since the launch of TIROS-N in 1978. These changes have resulted in both functional and organizational changes within NESDIS. In general, corporate knowledge of the detailed steps involved in processing satellite data has been greatly diminished. The following describes several factors contributing to our current situation: decreasing staff/budget and non-replacement of key positions, prompting centralization of many separate functions into one functional element; re-hosting of applications software from the original TIROS-N satellite processing subsystem to an IBM mainframe system (all capabilities inherent to the current system were not transferred in totality to the new system); the lack of properly documented software, procedures, and methodologies associated with detailed, step-by-step processing of satellite data, i.e. pre-launch, early orbit support, in-flight calibration, etc. In efforts to mitigate any further erosion of our knowledge base of operational satellite data processing with respect to calibration, this report is intended to document the instructional guidelines for processing of pre-launch and in-flight calibration data for instruments aboard the NOAA Polar-orbiting Operational Environmental Satellites (POES). Its purpose is to familiarize the reader--the user and managers of satellite acquired environmental data or data systems--with the basic operational technology, terminology and status of the NOAA polar satellite calibration system. Thus, a very brief description of calibration, radiometry, POES instrumentation, and procedures for prelaunch, early-orbit, in-flight, and post-launch support have been included as these subjects pertain to operational calibration.

  17. 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.

  18. Radiation calibration targets

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Several prominent features of Mars Pathfinder and surrounding terrain are seen in this image, taken by the Imager for Mars Pathfinder on July 4 (Sol 1), the spacecraft's first day on the Red Planet. Portions of a lander petal are at the lower part of the image. At the left, the mechanism for the high-gain antenna can be seen. The dark area along the right side of the image represents a portion of the low-gain antenna. The radiation calibration target is at the right. The calibration target is made up of a number of materials with well-characterized colors. The known colors of the calibration targets allow scientists to determine the true colors of the rocks and soils of Mars. Three bull's-eye rings provide a wide range of brightness for the camera, similar to a photographer's grayscale chart. In the middle of the bull's-eye is a 5-inch tall post that casts a shadow, which is distorted in this image due to its location with respect to the lander camera.

    A large rock is located at the near center of the image. Smaller rocks and areas of soil are strewn across the Martian terrain up to the horizon line.

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C.

  19. Fabrication and calibration of sensitively photoelastic biocompatible gelatin spheres

    NASA Astrophysics Data System (ADS)

    Fu, Henry; Ceniceros, Ericson; McCormick, Zephyr

    2013-11-01

    Photoelastic gelatin can be used to measure forces generated by organisms in complex environments. We describe manufacturing, storage, and calibration techniques for sensitive photoelastic gelatin spheres to be used in aqueous environments. Calibration yields a correlation between photoelastic signal and applied force to be used in future studies. Images for calibration were collected with a digital camera attached to a linear polariscope. The images were then processed in Matlab to determine the photoelastic response of each sphere. The effect of composition, gelatin concentration, glycerol concentration, sphere size, and temperature were all examined for their effect on signal response. The minimum detectable force and the repeatability of our calibration technique were evaluated for the same sphere, different spheres from the same fabrication batch, and spheres from different batches. The minimum force detectable is 10 ?N or less depending on sphere size. Factors which significantly contribute to errors in the calibration were explored in detail and minimized.

  20. 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.

  1. 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.

  2. [Laser-based radiometric calibration].

    PubMed

    Li, Zhi-gang; Zheng, Yu-quan

    2014-12-01

    Increasingly higher demands are put forward to spectral radiometric calibration accuracy and the development of new tunable laser based spectral radiometric calibration technology is promoted, along with the development of studies of terrestrial remote sensing, aeronautical and astronautical remote sensing, plasma physics, quantitative spectroscopy, etc. Internationally a number of national metrology scientific research institutes have built tunable laser based spectral radiometric calibration facilities in succession, which are traceable to cryogenic radiometers and have low uncertainties for spectral responsivity calibration and characterization of detectors and remote sensing instruments in the UK, the USA, Germany, etc. Among them, the facility for spectral irradiance and radiance responsivity calibrations using uniform sources (SIRCCUS) at the National Institute of Standards and Technology (NIST) in the USA and the Tunable Lasers in Photometry (TULIP) facility at the Physikalisch-Technische Bundesanstalt (PTB) in Germany have more representatives. Compared with lamp-monochromator systems, laser based spectral radiometric calibrations have many advantages, such as narrow spectral bandwidth, high wavelength accuracy, low calibration uncertainty and so on for radiometric calibration applications. In this paper, the development of laser-based spectral radiometric calibration and structures and performances of laser-based radiometric calibration facilities represented by the National Physical Laboratory (NPL) in the UK, NIST and PTB are presented, technical advantages of laser-based spectral radiometric calibration are analyzed, and applications of this technology are further discussed. Laser-based spectral radiometric calibration facilities can be widely used in important system-level radiometric calibration measurements with high accuracy, including radiance temperature, radiance and irradiance calibrations for space remote sensing instruments, and promote the development of aerospace, atmospheric physics, spectroscopy, biological science and so on in the fields of research and industry. PMID:25881452

  3. 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.

  4. 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.

  5. 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.

  6. In situ broadband cryogenic calibration for two-port superconducting microwave resonators

    SciTech Connect

    Yeh, Jen-Hao; Anlage, Steven M.

    2013-03-15

    We introduce an improved microwave calibration method for use in a cryogenic environment, based on a traditional three-standard calibration, the Thru-Reflect-Line (TRL) calibration. The modified calibration method takes advantage of additional information from multiple measurements of an ensemble of realizations of a superconducting resonator, as a new pseudo-Open standard, to correct errors in the TRL calibration. We also demonstrate an experimental realization of this in situ broadband cryogenic calibration system utilizing cryogenic switches. All calibration measurements are done in the same thermal cycle as the measurement of the resonator (requiring only an additional 20 min), thus avoiding 4 additional thermal cycles for traditional TRL calibration (which would require an additional 12 days). The experimental measurements on a wave-chaotic microwave billiard verify that the new method significantly improves the measured scattering matrix of a high-quality-factor superconducting resonator.

  7. In-situ Broadband Cryogenic Calibration for Two-port Superconducting Microwave Resonators

    E-print Network

    Jen-Hao Yeh; Steven M. Anlage

    2013-03-10

    We introduce an improved microwave calibration method for use in a cryogenic environment, based on a traditional three-standard calibration, the Thru-Reflect-Line (TRL) calibration. The modified calibration method takes advantage of additional information from multiple measurements of an ensemble of realizations of a superconducting resonator, as a new pseudo-Open standard, to correct errors in the TRL calibration. We also demonstrate an experimental realization of this in-situ broadband cryogenic calibration system utilizing cryogenic switches. All calibration measurements are done in the same thermal cycle as the measurement of the resonator (requiring only an additional 20 minutes), thus avoiding 4 additional thermal cycles for traditional TRL calibration (which would require an additional 12 days). The experimental measurements on a wave-chaotic microwave billiard verify that the new method significantly improves the measured scattering matrix of a high-quality-factor superconducting resonator.

  8. Use of Radiometrically Calibrated Flat-Plate Calibrators in Calibration of Radiation Thermometers

    NASA Astrophysics Data System (ADS)

    Cárdenas-García, D.; Méndez-Lango, E.

    2015-08-01

    Most commonly used, low-temperature, infrared thermometers have large fields of view sizes that make them difficult to be calibrated with narrow aperture blackbodies. Flat-plate calibrators with large emitting surfaces have been proposed for calibrating these infrared thermometers. Because the emissivity of the flat plate is not unity, its radiance temperature is wavelength dependent. For calibration, the wavelength pass band of the device under test should match that of the reference infrared thermometer. If the device under test and reference radiometer have different pass bands, then it is possible to calculate the corresponding correction if the emissivity of the flat plate is known. For example, a correction of at is required when calibrating a infrared thermometer with a "" radiometrically calibrated flat-plate calibrator. A method is described for using a radiometrically calibrated flat-plate calibrator that covers both cases of match and mismatch working wavelength ranges of a reference infrared thermometer and infrared thermometers to be calibrated with the flat-plate calibrator. Also, an application example is included in this paper.

  9. Performance comparison of accelerometer calibration algorithms based on 3D-ellipsoid fitting methods.

    PubMed

    Gietzelt, Matthias; Wolf, Klaus-Hendrik; Marschollek, Michael; Haux, Reinhold

    2013-07-01

    Calibration of accelerometers can be reduced to 3D-ellipsoid fitting problems. Changing extrinsic factors like temperature, pressure or humidity, as well as intrinsic factors like the battery status, demand to calibrate the measurements permanently. Thus, there is a need for fast calibration algorithms, e.g. for online analyses. The primary aim of this paper is to propose a non-iterative calibration algorithm for accelerometers with the focus on minimal execution time and low memory consumption. The secondary aim is to benchmark existing calibration algorithms based on 3D-ellipsoid fitting methods. We compared the algorithms regarding the calibration quality and the execution time as well as the number of quasi-static measurements needed for a stable calibration. As evaluation criterion for the calibration, both the norm of calibrated real-life measurements during inactivity and simulation data was used. The algorithms showed a high calibration quality, but the execution time differed significantly. The calibration method proposed in this paper showed the shortest execution time and a very good performance regarding the number of measurements needed to produce stable results. Furthermore, this algorithm was successfully implemented on a sensor node and calibrates the measured data on-the-fly while continuously storing the measured data to a microSD-card. PMID:23566707

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

    SciTech Connect

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

    2014-12-08

    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?×?10{sup 6} 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.

  11. Procedures used in the calibration of AC calibrators

    SciTech Connect

    Salazar, M.T.

    1991-02-01

    This report describes an automatic calibration system used in the calibration of all precision AC calibrators. 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. 5 refs., 3 figs.

  12. CP-50 calibration facility radiological safety assessment document

    SciTech Connect

    Chilton, M.W.; Hill, R.L.; Eubank, B.F.

    1980-03-01

    The CP-50 Calibration Facility Radiological Safety Assessment document, prepared at the request of the Nevada Operations Office of the US Department of Energy to satisfy provisions of ERDA Manual Chapter 0531, presents design features, systems controls, and procedures used in the operation of the calibration facility. Site and facility characteristics and routine and non-routine operations, including hypothetical incidents or accidents are discussed and design factors, source control systems, and radiation monitoring considerations are described.

  13. On-line in-syringe magnetic stirring assisted dispersive liquid-liquid microextraction HPLC - UV method for UV filters determination using 1-hexyl-3-methylimidazolium hexafluorophosphate as extractant.

    PubMed

    Suárez, Ruth; Clavijo, Sabrina; Avivar, Jessica; Cerdà, Víctor

    2016-02-01

    An environmental friendly and fully automated method using in-syringe magnetic stirring assisted dispersive liquid-liquid microextraction coupled with high-performance liquid chromatography has been developed for the determination of UV filters in environmental water samples. The main "green" features on this method are the use of an ionic liquid as extracting solvent, avoiding the use of chlorinated solvents, and the on-line microextraction, preconcentration, separation and detection minimizing the use of reagents and so the waste generation. After sample treatment, 20µL of the organic droplet was injected onto the HPLC-UV system. Various parameters affecting the extraction efficiency were studied using multivariate optimization approach, including the quantity of extraction and dispersive solvents, extraction and sedimentation time, ionic strength and pH. Under optimized conditions, limits of detection were within the range of 0.08-12µg/L, for 3.5mL sample volume. Linearity ranges were up to 500µg/L for the UV-filters studied. Furthermore, enrichment factors ranging from 11 to 23 folds were obtained. Intra- and inter-assay precisions were 6% and 8%, respectively. Finally, the proposed method was successfully applied to determine UV filters in surface seawater and swimming pool samples attaining satisfactory recoveries over the range of 89-114% and 86-107%, respectively. PMID:26653488

  14. 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.

  15. Piezoelectric trace vapor calibrator

    SciTech Connect

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

    2006-08-15

    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 deg. 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 290 fg/l to 1.05 {mu}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.

  16. Weed Busters: Sprayer Calibration Guide 

    E-print Network

    McGinty, Allan; Hanselka, C. Wayne; Lyons, Robert K.; Hart, Charles R.; Cadenhead, J. F.

    2005-03-07

    , especially when boom- less nozzles are used. ?Read and follow the herbicide label directions. L-5465 1/05 Sprayer Calibration Guide Safe and effective four-step method to calibrate herbicide sprays Weed Treatment Series Allan McGinty, Extension Range... can become excessive; you may be in violation of the label; and you might cause environmental dam- age. If you apply too little herbicide, the weeds may not be controlled adequately. Many sprayer calibration methods are available and can be used...

  17. Internal Water Vapor Photoacoustic Calibration

    NASA Technical Reports Server (NTRS)

    Pilgrim, Jeffrey S.

    2009-01-01

    Water vapor absorption is ubiquitous in the infrared wavelength range where photoacoustic trace gas detectors operate. This technique allows for discontinuous wavelength tuning by temperature-jumping a laser diode from one range to another within a time span suitable for photoacoustic calibration. The use of an internal calibration eliminates the need for external calibrated reference gases. Commercial applications include an improvement of photoacoustic spectrometers in all fields of use.

  18. 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.

  19. 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.

  20. 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.

  1. Small Scale Mass Flow Plug Calibration

    NASA Technical Reports Server (NTRS)

    Sasson, Jonathan

    2015-01-01

    A simple control volume model has been developed to calculate the discharge coefficient through a mass flow plug (MFP) and validated with a calibration experiment. The maximum error of the model in the operating region of the MFP is 0.54%. The model uses the MFP geometry and operating pressure and temperature to couple continuity, momentum, energy, an equation of state, and wall shear. Effects of boundary layer growth and the reduction in cross-sectional flow area are calculated using an in- integral method. A CFD calibration is shown to be of lower accuracy with a maximum error of 1.35%, and slower by a factor of 100. Effects of total pressure distortion are taken into account in the experiment. Distortion creates a loss in flow rate and can be characterized by two different distortion descriptors.

  2. 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

  3. Quality Management and Calibration

    NASA Astrophysics Data System (ADS)

    Merkus, Henk G.

    Good specification of a product’s performance requires adequate characterization of relevant properties. Particulate products are usually characterized by some PSD, shape or porosity parameter(s). For proper characterization, adequate sampling, dispersion, and measurement procedures should be available or developed and skilful personnel should use appropriate, well-calibrated/qualified equipment. The characterization should be executed, in agreement with customers, in a wellorganized laboratory. All related aspects should be laid down in a quality handbook. The laboratory should provide proof for its capability to perform the characterization of stated products and/or reference materials within stated confidence limits. This can be done either by internal validation and audits or by external GLP accreditation.

  4. Robot geometry calibration

    NASA Technical Reports Server (NTRS)

    Hayati, Samad; Tso, Kam; Roston, Gerald

    1988-01-01

    Autonomous robot task execution requires that the end effector of the robot be positioned accurately relative to a reference world-coordinate frame. The authors present a complete formulation to identify the actual robot geometric parameters. The method applies to any serial link manipulator with arbitrary order and combination of revolute and prismatic joints. A method is also presented to solve the inverse kinematic of the actual robot model which usually is not a so-called simple robot. Experimental results performed by utilizing a PUMA 560 with simple measurement hardware are presented. As a result of this calibration a precision move command is designed and integrated into a robot language, RCCL, and used in the NASA Telerobot Testbed.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Uniform calibration of night vision goggles and test sets

    NASA Astrophysics Data System (ADS)

    Eppeldauer, George P.

    2007-10-01

    There are orders of magnitude differences between the ~0.1 % (k=2) uncertainty of NIST reference detector calibrations and the uncertainty of night vision (NV) goggle measurements. NIST developed a night vision radiometer calibration facility including NV radiometer transfer standards. The transfer standards, that propagate the radiance responsivity scale to the military primary standards laboratories, are calibrated against a NIST reference radiometer. The reference radiometer has been calibrated on the NIST Spectral Comparator Facility (SCF) for spectral power and irradiance responsivities. Spectral considerations are discussed to lower the uncertainties of the radiance responsivity scale transfer to the test sets and then to the goggles. Since direct determination of the final uncertainties in goggle calibrations and measurements is difficult, models have been made to estimate the most important uncertainty components based on individual spectral measurements of the applied source distributions and radiometer spectral responsivities. It is also shown, that because of source spectral mismatch problems, the goggle measurement uncertainty at applications can be much higher than at calibration. A suggestion is being made to mimic the no-moon (stars only) night sky radiation distribution using several LEDs in the test-sets to decrease the large spectral mismatch errors. A broad-band correction factor has been developed to further decrease calibration uncertainty when the goggles to be used have different spectral responsivities than the standard. Geometrical considerations to optimize the radiance measurement angle and the out-of-target blocking are also discussed to decrease the uncertainty in the radiance responsivity transfer.

  11. Skew redundant MEMS IMU calibration using a Kalman filter

    NASA Astrophysics Data System (ADS)

    Jafari, M.; Sahebjameyan, M.; Moshiri, B.; Najafabadi, T. A.

    2015-10-01

    In this paper, a novel calibration procedure for skew redundant inertial measurement units (SRIMUs) based on micro-electro mechanical systems (MEMS) is proposed. A general model of the SRIMU measurements is derived which contains the effects of bias, scale factor error and misalignments. For more accuracy, the effect of lever arms of the accelerometers to the center of the table are modeled and compensated in the calibration procedure. Two separate Kalman filters (KFs) are proposed to perform the estimation of error parameters for gyroscopes and accelerometers. The predictive error minimization (PEM) stochastic modeling method is used to simultaneously model the effect of bias instability and random walk noise on the calibration Kalman filters to diminish the biased estimations. The proposed procedure is simulated numerically and has expected experimental results. The calibration maneuvers are applied using a two-axis angle turntable in a way that the persistency of excitation (PE) condition for parameter estimation is met. For this purpose, a trapezoidal calibration profile is utilized to excite different deterministic error parameters of the accelerometers and a pulse profile is used for the gyroscopes. Furthermore, to evaluate the performance of the proposed KF calibration method, a conventional least squares (LS) calibration procedure is derived for the SRIMUs and the simulation and experimental results compare the functionality of the two proposed methods with each other.

  12. 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

  13. Calibration of the ARID robot

    NASA Technical Reports Server (NTRS)

    Doty, Keith L

    1992-01-01

    The author has formulated a new, general model for specifying the kinematic properties of serial manipulators. The new model kinematic parameters do not suffer discontinuities when nominally parallel adjacent axes deviate from exact parallelism. From this new theory the author develops a first-order, lumped-parameter, calibration-model for the ARID manipulator. Next, the author develops a calibration methodology for the ARID based on visual and acoustic sensing. A sensor platform, consisting of a camera and four sonars attached to the ARID end frame, performs calibration measurements. A calibration measurement consists of processing one visual frame of an accurately placed calibration image and recording four acoustic range measurements. A minimum of two measurement protocols determine the kinematics calibration-model of the ARID for a particular region: assuming the joint displacements are accurately measured, the calibration surface is planar, and the kinematic parameters do not vary rapidly in the region. No theoretical or practical limitations appear to contra-indicate the feasibility of the calibration method developed here.

  14. 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.

  15. Antenna Position Calibration Melvyn Wright

    E-print Network

    Antenna 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 of HA and DEC provide data from which the antenna positions are determined. If the antenna positions

  16. 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

  17. Approaches on calibration of bolometer and establishment of bolometer calibration device

    NASA Astrophysics Data System (ADS)

    Xia, Ming; Gao, Jianqiang; Ye, Jun'an; Xia, Junwen; Yin, Dejin; Li, Tiecheng; Zhang, Dong

    2015-10-01

    Bolometer is mainly used for measuring thermal radiation in the field of public places, labor hygiene, heating and ventilation and building energy conservation. The working principle of bolometer is under the exposure of thermal radiation, temperature of black absorbing layer of detector rise after absorption of thermal radiation, which makes the electromotive force produced by thermoelectric. The white light reflective layer of detector does not absorb thermal radiation, so the electromotive force produced by thermoelectric is almost zero. A comparison of electromotive force produced by thermoelectric of black absorbing layer and white reflective layer can eliminate the influence of electric potential produced by the basal background temperature change. After the electromotive force which produced by thermal radiation is processed by the signal processing unit, the indication displays through the indication display unit. The measurement unit of thermal radiation intensity is usually W/m2 or kW/m2. Its accurate and reliable value has important significance for high temperature operation, labor safety and hygiene grading management. Bolometer calibration device is mainly composed of absolute radiometer, the reference light source, electric measuring instrument. Absolute radiometer is a self-calibration type radiometer. Its working principle is using the electric power which can be accurately measured replaces radiation power to absolutely measure the radiation power. Absolute radiometer is the standard apparatus of laser low power standard device, the measurement traceability is guaranteed. Using the calibration method of comparison, the absolute radiometer and bolometer measure the reference light source in the same position alternately which can get correction factor of irradiance indication. This paper is mainly about the design and calibration method of the bolometer calibration device. The uncertainty of the calibration result is also evaluated.

  18. 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.

  19. 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.

  20. 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.

  1. Germanium resistance thermometer calibration at superfluid helium temperatures

    NASA Technical Reports Server (NTRS)

    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.

  2. 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.

  3. Cobalt source calibration

    SciTech Connect

    Rizvi, H.M.

    1999-12-03

    The data obtained from these tests determine the dose rate of the two cobalt sources in SRTC. Building 774-A houses one of these sources while the other resides in room C-067 of Building 773-A. The data from this experiment shows the following: (1) The dose rate of the No.2 cobalt source in Building 774-A measured 1.073 x 10{sup 5} rad/h (June 17, 1999). The dose rate of the Shepherd Model 109 Gamma cobalt source in Building 773-A measured 9.27 x 10{sup 5} rad/h (June 25, 1999). These rates come from placing the graduated cylinder containing the dosimeter solution in the center of the irradiation chamber. (2) Two calibration tests in the 774-A source placed the graduated cylinder with the dosimeter solution approximately 1.5 inches off center in the axial direction. This movement of the sample reduced the measured dose rate 0.92% from 1.083 x 10{sup 5} rad/h to 1.073 x 10{sup 5} rad/h. and (3) A similar test in the cobalt source in 773-A placed the graduated cylinder approximately 2.0 inches off center in the axial direction. This change in position reduced the measured dose rate by 10.34% from 1.036 x 10{sup 6} to 9.27 x 10{sup 5}. This testing used chemical dosimetry to measure the dose rate of a radioactive source. In this method, one determines the dose by the chemical change that takes place in the dosimeter. For this calibration experiment, the author used a Fricke (ferrous ammonium sulfate) dosimeter. This solution works well for dose rates to 10{sup 7} rad/h. During irradiation of the Fricke dosimeter solution the Fe{sup 2+} ions ionize to Fe{sup 3+}. When this occurs, the solution acquires a slightly darker tint (not visible to the human eye). To determine the magnitude of the change in Fe ions, one places the solution in an UV-VIS Spectrophotometer. The UV-VIS Spectrophotometer measures the absorbency of the solution. Dividing the absorbency by the total time (in minutes) of exposure yields the dose rate.

  4. Improved camera calibration method based on perpendicularity compensation for binocular stereo vision measurement system.

    PubMed

    Jia, Zhenyuan; Yang, Jinghao; Liu, Wei; Wang, Fuji; Liu, Yang; Wang, Lingli; Fan, Chaonan; Zhao, Kai

    2015-06-15

    High-precision calibration of binocular vision systems plays an important role in accurate dimensional measurements. In this paper, an improved camera calibration method is proposed. First, an accurate intrinsic parameters calibration method based on active vision with perpendicularity compensation is developed. Compared to the previous work, this method eliminates the effect of non-perpendicularity of the camera motion on calibration accuracy. The principal point, scale factors, and distortion factors are calculated independently in this method, thereby allowing the strong coupling of these parameters to be eliminated. Second, an accurate global optimization method with only 5 images is presented. The results of calibration experiments show that the accuracy of the calibration method can reach 99.91%. PMID:26193503

  5. Airdata Measurement and Calibration. Chapter 11

    NASA Technical Reports Server (NTRS)

    Haering, Edward A., Jr.

    2005-01-01

    This Section 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 Section 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 section is not intended to be all inclusive; readers should review AGARDograph 300, Volume 1, "Calibration of Airdata Systems and Flow Direction Sensors" for more detailed information. [11-1] References 11-2, 11-3, and 11-4 also supply pertinent information to better understand airdata measurement and calibration and related terminology. Airdata are vital to successfully complete an aircraft's mission and are derived from the air surrounding the aircraft. These airdata encompass indicated and true airspeed, pressure altitude, ambient air temperature, angles of attack and sideslip, Mach number, and rate of climb. Typically, pitot and static pressures are sensed and converted (by mechanical means in the instruments themselves) into indications on the altimeter, vertical speed indicator, airspeed indicator, and Machmeter. Similarly, measured local flow angles establish angles of attack and sideslip, and the outside air temperature is measured and indicated in the cockpit. (Instruments that can perform the conversion, such as airspeed indicators, altimeters, and Machmeters, do not correct for errors in the input values.) These measured parameters are commonly input to the airdata computer which, using appropriate algorithms and correction factors (or calibrations, as discussed later), can provide other parameters, such as true airspeed, required by the aircraft's avionics or flight control system. The presence of the aircraft in the airstream causes input errors to the measuring instruments - the aircraft disturbs the air that it flies through, thereby also disturbing the airdata measurements. Figure 11-1 shows the airflow around an airplane wing. The air above the wing has lower pressure than the ambient air, while the pressure below the wing is higher than the ambient air. Compressibility and shock waves also disturb the air and affect the measurements. Compressibility effects become important above approximately Mach number 0.3. As a result the static pressure around an airplane varies considerably with location. Local flow angles also differ from the free-stream flow direction. In straight-and-level flight the airflow rises to the wing leading edge and falls below the trailing edge, causing errors in flow direction measurements. To some extent these errors can be studied in wind tunnels, but wind-tunnel measurements cannot replace in-flight measurements.

  6. Calibration of the Oscillating Screen Viscometer

    NASA Technical Reports Server (NTRS)

    Berg, Robert F.; Moldover, Michael R.

    1993-01-01

    We have devised a calibration procedure for the oscillating screen viscometer which can provide the accuracy needed for the flight measurement of viscosity near the liquid-vapor critical point of xenon. The procedure, which makes use of the viscometer's wide bandwidth and hydrodynamic similarity, allows the viscometer to be self-calibrating. To demonstrate the validity of this procedure we measured the oscillator's transfer function under a wide variety of conditions. We obtained data using CO2 at temperatures spanning a temperature range of 35 K and densities varying by a factor of 165, thereby encountering viscosity variations as great as 50%. In contrast the flight experiment will be performed over a temperature range of 29 K and at only a single density, and the viscosity is expected to change by less than 40%. The measurements show that, after excluding data above 10 Hz (where frequency-dependent corrections are poorly modeled) and making a plausible adjustment to the viscosity value used at high density, the viscometer's behavior is fully consistent with the use of hydrodynamic similarity for calibration. Achieving this agreement required understanding a 1% anelastic effect present in the oscillator's torsion fiber.

  7. Application of In-Syringe Dispersive Liquid-Liquid Microextraction Coupled to GC/FID for Determination of Trace Contamination of Phthalate Esters in Water Samples.

    PubMed

    Sargazi, Shahnaz; Mirzaei, Ramazan; Rahmani, Mashaallah; Sheikh, Masoome

    2015-09-01

    In this work, a simple and easy to handle one-step in-syringe setup for the dispersive liquid-liquid microextraction method has been developed for preconcentration of trace quantities of four kinds of phthalate esters (PEs) in water samples as a prior step to its determination by gas chromatography/flame ionization detector. The environmental pollution at this method has been limited due to using a glass syringe as extraction unit and also a very small amount of n-hexane as a safe solvent. Some important parameters such as the type of extraction and disperser solvents, extraction and disperser solvents volume, sample volume and ionic strength were investigated and optimized. Validation experiments showed that the optimized method had precision (1.7-6.9%) and high recovery (94.32-104.7%), and the limits of detection were from 0.406 to 1.33 µg L(-1). At the end, the method was successfully applied for the determination of PEs in real water samples. PMID:25713105

  8. Calibration: Practical experience with ERS-1

    NASA Technical Reports Server (NTRS)

    Louet, Jacques

    1993-01-01

    Viewgraphs and discussion of calibration:practical experience with ERS-1 are presented. Topics covered include: radiometric calibration, geometric calibration, phase calibration, and polarimetric calibration. Basic synthetic aperture radar (SAR) measurement parameters are radar backscattering, target position, target speed, and polarization. SAR calibration facilitates quantitative measurements needed to derive geophysical parameters of the area under observation from basic SAR measurements (e.g. soil moisture, biomass, ocean wave energy, ocean currents, ice type, and ice flow).

  9. Mexican national pyronometer network calibration

    NASA Astrophysics Data System (ADS)

    VAldes, M.; Villarreal, L.; Estevez, H.; Riveros, D.

    2013-12-01

    In order to take advantage of the solar radiation as an alternate energy source it is necessary to evaluate the spatial and temporal availability. The Mexican National Meterological Service (SMN) has a network with 136 meteorological stations, each coupled with a pyronometer for measuring the global solar radiation. Some of these stations had not been calibrated in several years. The Mexican Department of Energy (SENER) in order to count on a reliable evaluation of the solar resource funded this project to calibrate the SMN pyrometer network and validate the data. The calibration of the 136 pyronometers by the intercomparison method recommended by the World Meterological Organization (WMO) requires lengthy observations and specific environmental conditions such as clear skies and a stable atmosphere, circumstances that determine the site and season of the calibration. The Solar Radiation Section of the Instituto de Geofísica of the Universidad Nacional Autónoma de México is a Regional Center of the WMO and is certified to carry out the calibration procedures and emit certificates. We are responsible for the recalibration of the pyronometer network of the SMN. A continuous emission solar simulator with exposed areas with 30cm diameters was acquired to reduce the calibration time and not depend on atmospheric conditions. We present the results of the calibration of 10 thermopile pyronometers and one photovoltaic cell by the intercomparison method with more than 10000 observations each and those obtained with the solar simulator.

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. Vicarious calibration of the Geostationary Ocean Color Imager.

    PubMed

    Ahn, Jae-Hyun; Park, Young-Je; Kim, Wonkook; Lee, Boram; Oh, Im Sang

    2015-09-01

    Measurements of ocean color from Geostationary Ocean Color Imager (GOCI) with a moderate spatial resolution and a high temporal frequency demonstrate high value for a number of oceanographic applications. This study aims to propose and evaluate the calibration of GOCI as needed to achieve the level of radiometric accuracy desired for ocean color studies. Previous studies reported that the GOCI retrievals of normalized water-leaving radiances (nLw) are biased high for all visible bands due to the lack of vicarious calibration. The vicarious calibration approach described here relies on the assumed constant aerosol characteristics over the open-ocean sites to accurately estimate atmospheric radiances for the two near-infrared (NIR) bands. The vicarious calibration of visible bands is performed using in situ nLw measurements and the satellite-estimated atmospheric radiance using two NIR bands over the case-1 waters. Prior to this analysis, the in situ nLw spectra in the NIR are corrected by the spectrum optimization technique based on the NIR similarity spectrum assumption. The vicarious calibration gain factors derived for all GOCI bands (except 865nm) significantly improve agreement in retrieved remote-sensing reflectance (Rrs) relative to in situ measurements. These gain factors are independent of angular geometry and possible temporal variability. To further increase the confidence in the calibration gain factors, a large data set from shipboard measurements and AERONET-OC is used in the validation process. It is shown that the absolute percentage difference of the atmospheric correction results from the vicariously calibrated GOCI system is reduced by ~6.8%. PMID:26368426

  15. 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...

  16. 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.

  17. 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

  18. Improving Planck calibration by including frequency-dependent relativistic corrections

    E-print Network

    Quartin, Miguel

    2015-01-01

    The Planck satellite detectors are calibrated in the 2015 release using the "orbital dipole", which is the time-dependent dipole generated by the Doppler effect due to the motion of the satellite around the Sun. Such an effect has also relativistic time-dependent corrections of relative magnitude 10^(-3), due to coupling with the "solar dipole" (the motion of the Sun compared to the CMB rest frame), which are included in the data calibration by the Planck collaboration. We point out that such corrections are subject to a frequency-dependent multiplicative factor. This factor differs from unity especially at the highest frequencies, relevant for the HFI instrument. Since currently Planck calibration errors are dominated by systematics, to the point that polarization data is currently unreliable at large scales, such a correction can in principle be highly relevant for future data releases.

  19. Improving Planck calibration by including frequency-dependent relativistic corrections

    NASA Astrophysics Data System (ADS)

    Quartin, Miguel; Notari, Alessio

    2015-09-01

    The Planck satellite detectors are calibrated in the 2015 release using the "orbital dipole", which is the time-dependent dipole generated by the Doppler effect due to the motion of the satellite around the Sun. Such an effect has also relativistic time-dependent corrections of relative magnitude 10?3, due to coupling with the "solar dipole" (the motion of the Sun compared to the CMB rest frame), which are included in the data calibration by the Planck collaboration. We point out that such corrections are subject to a frequency-dependent multiplicative factor. This factor differs from unity especially at the highest frequencies, relevant for the HFI instrument. Since currently Planck calibration errors are dominated by systematics, to the point that polarization data is currently unreliable at large scales, such a correction can in principle be highly relevant for future data releases.

  20. 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....

  1. 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.

  2. Influence of the physical data to calibrate TEPCs.

    PubMed

    Chiriotti, S; Moro, D; Conte, V; Colautti, P; Grosswendt, B; Sterpin, E; Vynckier, S

    2015-09-01

    Tissue-equivalent proportional counters (TEPCs) measure distributions of ionisations, produced in the gas cavity by the radiation field which are afterwards converted into distributions of energy imparted by applying a calibration factor. To calibrate the pulse-height spectra, first, a marker point must be identified in the measured spectrum. Then, an accurate value of lineal energy must be assigned to this marker. A common marker that is often used for calibration is the so-called proton-edge (p-edge). It is a distinctive feature of a proton or neutron spectrum which corresponds to the maximum amount of energy that a proton can deposit in the active volume of the detector. A precise method to identify the marker point was applied to identify the p-edge with an uncertainty below 1 %. To evaluate the final uncertainty of the calibration, the uncertainty of the energy value assigned to the p-edge must also be considered. This value can be evaluated using different energy-range tables. This study investigates how the choice of different input databases for calibration purposes influences the calibration. The effect of three different frequently used sets of input data was analysed for pure propane gas and for propane-TE gas mixture. PMID:25877542

  3. 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.

  4. Blackbody comparator for thermocouple calibration

    SciTech Connect

    Ojanen, M.; Hahtela, O. M.; Heinonen, M.

    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. Relevance of ellipse eccentricity for camera calibration

    NASA Astrophysics Data System (ADS)

    Mordwinzew, W.; Tietz, B.; Boochs, F.; Paulus, D.

    2015-05-01

    Plane circular targets are widely used within calibrations of optical sensors through photogrammetric set-ups. Due to this popularity, their advantages and disadvantages are also well studied in the scientific community. One main disadvantage occurs when the projected target is not parallel to the image plane. In this geometric constellation, the target has an elliptic geometry with an offset between its geometric and its projected center. This difference is referred to as ellipse eccentricity and is a systematic error which, if not treated accordingly, has a negative impact on the overall achievable accuracy. The magnitude and direction of eccentricity errors are dependent on various factors. The most important one is the target size. The bigger an ellipse in the image is, the bigger the error will be. Although correction models dealing with eccentricity have been available for decades, it is mostly seen as a planning task in which the aim is to choose the target size small enough so that the resulting eccentricity error remains negligible. Besides the fact that advanced mathematical models are available and that the influence of this error on camera calibration results is still not completely investigated, there are various additional reasons why bigger targets can or should not be avoided. One of them is the growing image resolution as a by-product from advancements in the sensor development. Here, smaller pixels have a lower S/N ratio, necessitating more pixels to assure geometric quality. Another scenario might need bigger targets due to larger scale differences whereas distant targets should still contain enough information in the image. In general, bigger ellipses contain more contour pixels and therefore more information. This supports the target-detection algorithms to perform better even at non-optimal conditions such as data from sensors with a high noise level. In contrast to rather simple measuring situations in a stereo or multi-image mode, the impact of ellipse eccentricity on image blocks cannot be modeled in a straight forward fashion. Instead, simulations can help make the impact visible, and to distinguish critical or less critical situations. In particular, this might be of importance for calibrations, as undetected influence on the results will affect further projects where the same camera will be used. This paper therefore aims to point out the influence of ellipse eccentricities on camera calibrations, by using two typical calibration bodies: planar and cube shaped calibration. In the first step, their relevance and influence on the image measurements, object- and camera geometry is shown with numeric examples. Differences and similarities between both calibration bodies are identified and discussed. In the second step, practical relevance of a correction is proven in a real calibration. Finally, a conclusion is drawn followed by recommendations to handle ellipse eccentricity in the practice.

  6. 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…

  7. An accurate method for calibrating photoluminescence-based lifetime images on multi-crystalline silicon wafers

    E-print Network

    -crystalline silicon wafers H.C. Sio a,n , S.P. Phang a , T. Trupke b , D. Macdonald a a Research School of Engineering for silicon wafers with inhomogeneous lifetime distributions, such as multi-crystalline silicon wafers, based on a calibration factor extracted from a separate, homogeneous, mono-crystalline calibration wafer and simple

  8. Hydrologic calibration of paired watersheds using a MOSUM approach

    SciTech Connect

    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.

    2015-01-09

    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.

  9. Hydrologic calibration of paired watersheds using a MOSUM approach

    DOE PAGESBeta

    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.

    2015-01-09

    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 managedmore »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.« less

  10. Design, manufacture, and calibration of infrared radiometric blackbody sources

    SciTech Connect

    Byrd, D.A.; Michaud, F.D.; Bender, S.C.

    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.

  11. MODEL CALIBRATION REPORT FOR THE HOUSATONIC RIVER

    EPA Science Inventory

    The Model Calibration Report will present a comparison of the model calibration runs to existing data for the calibration period, over a two year time frame. In addition, the model predictions for the calibration period will be compared to other supporting analyses, such as alter...

  12. 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.

  13. 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.

  14. 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

  15. Proof-of-concept demonstration of a total internal reflection based module for fluorescence and absorbance detection using a 3D-printed syringe pump

    NASA Astrophysics Data System (ADS)

    Verschooten, Tom; Ottevaere, Heidi; Vervaeke, Michael; Van Erps, Jürgen; Thienpont, Hugo

    2014-05-01

    In this paper we demonstrate the proof-of-concept of an optofluidic module capable of simultaneous laser-induced fluorescence (LIF) and absorbance (ABS) detection based on total internal reflection (TIR) optics. We discuss the design of the optofluidic detection module, its fabrication, and the setup used for the proof-of-concept. The injection of sample under test is done using two 3D printed syringe pumps, managing accurate injection and repeatable sample propagation through the detector module. We discuss the process of development behind these pumps and review their technical specifications. With this demonstrator setup we find that the limits of detection for the ABS and LIF detection of coumarin 480 are 500 nM and 100 nM respectively.

  16. 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...

  17. 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.

  18. Deformability measurement of red blood cells using a microfluidic channel array and an air cavity in a driving syringe with high throughput and precise detection of subpopulations.

    PubMed

    Kang, Yang Jun; Ha, Young-Ran; Lee, Sang-Joon

    2016-01-01

    Red blood cell (RBC) deformability has been considered a potential biomarker for monitoring pathological disorders. High throughput and detection of subpopulations in RBCs are essential in the measurement of RBC deformability. In this paper, we propose a new method to measure RBC deformability by evaluating temporal variations in the average velocity of blood flow and image intensity of successively clogged RBCs in the microfluidic channel array for specific time durations. In addition, to effectively detect differences in subpopulations of RBCs, an air compliance effect is employed by adding an air cavity into a disposable syringe. The syringe was equally filled with a blood sample (Vblood = 0.3 mL, hematocrit = 50%) and air (Vair = 0.3 mL). Owing to the air compliance effect, blood flow in the microfluidic device behaved transiently depending on the fluidic resistance in the microfluidic device. Based on the transient behaviors of blood flows, the deformability of RBCs is quantified by evaluating three representative parameters, namely, minimum value of the average velocity of blood flow, clogging index, and delivered blood volume. The proposed method was applied to measure the deformability of blood samples consisting of homogeneous RBCs fixed with four different concentrations of glutaraldehyde solution (0%-0.23%). The proposed method was also employed to evaluate the deformability of blood samples partially mixed with normal RBCs and hardened RBCs. Thereafter, the deformability of RBCs infected by human malaria parasite Plasmodium falciparum was measured. As a result, the three parameters significantly varied, depending on the degree of deformability. In addition, the deformability measurement of blood samples was successfully completed in a short time (?10 min). Therefore, the proposed method has significant potential in deformability measurement of blood samples containing hematological diseases with high throughput and precise detection of subpopulations in RBCs. PMID:26616556

  19. Calibration of ionization chamber for ¹?F and ??Ga.

    PubMed

    da Silva, Carlos J; de Oliveira, Estela M; Iwahara, A; Delgado, José U; Poledna, R; de Oliveira, Antônio E; Moreira, Denise S; da Silva, Ronaldo L; Gomes, Regio dos Santos; de Veras, Eduardo V

    2014-05-01

    In order to maintain the results of primary activity standardizations carried out in 2011 the LNMRI has determined the calibration factors for a pressurized 4?-ionization chamber for the nuclides (18)F and (68)Ga. This ionization chamber is coupled to a 6517A Keithley electrometer which is controlled by a homemade LabVIEW program. This paper will describe the main issues related to the calibration of an ionization chamber system for positron emitters and short half-life radionuclides such as timing, current measurement, background, decay, and (226)Ra check source measurements. PMID:24361323

  20. LMC clusters - Age calibration and age distribution revisited

    NASA Technical Reports Server (NTRS)

    Elson, Rebecca A.; Fall, S. Michael

    1988-01-01

    The empirical age relation for star clusters in the Large Magellanic Cloud presented by Elson and Fall (1985) are reexamined using ages based only on main-sequence turnoffs. The present sample includes 57 clusters, 24 of which have color-magnitude diagrams published since 1985. The new calibration is very similar to that found previously, and the scatter in the relation corresponds to uncertainties of about a factor of 2 in age. The age distribution derived from the new calibration does not differ significantly from that derived in earlier work. It is compared with age distributions estimated by other authors for different samples of clusters, and the results are discussed.

  1. Self-calibrating multiplexer circuit

    SciTech Connect

    Wahl, C.P.

    1997-04-29

    A time domain multiplexer system with automatic determination of acceptable multiplexer output limits, error determination, or correction is comprised of a time domain multiplexer, a computer, a constant current source capable of at least three distinct current levels, and two series resistances employed for calibration and testing. A two point linear calibration curve defining acceptable multiplexer voltage limits may be defined by the computer by determining the voltage output of the multiplexer to very accurately known input signals developed from predetermined current levels across the series resistances. Drift in the multiplexer may be detected by the computer when the output voltage limits, expected during normal operation, are exceeded, or the relationship defined by the calibration curve is invalidated. 3 figs.

  2. Self-calibrating multiplexer circuit

    SciTech Connect

    Wahl, C.P.

    1995-12-31

    A time domain multiplexer system with automatic determination of acceptable multiplexer output limits, error determination, or correction is comprised of a time domain multiplexer, a computer, a constant current source capable of at least three distinct current levels, and two series resistances employed for calibration and testing. A two point linear calibration curve defining acceptable multiplexer voltage limits may be defined by the computer by determining the voltage output of the multiplexer to very accurately known input signals developed from predetermined current levels across the series resistances. Drift in the multiplexer may be detected by the computer when the output voltage limits, expected during normal operation, are exceeded, or the relationship defined by the calibration curve is invalidated.

  3. Self-calibrating multiplexer circuit

    DOEpatents

    Wahl, Chris P. (North Huntingdon, PA)

    1997-01-01

    A time domain multiplexer system with automatic determination of acceptable multiplexer output limits, error determination, or correction is comprised of a time domain multiplexer, a computer, a constant current source capable of at least three distinct current levels, and two series resistances employed for calibration and testing. A two point linear calibration curve defining acceptable multiplexer voltage limits may be defined by the computer by determining the voltage output of the multiplexer to very accurately known input signals developed from predetermined current levels across the series resistances. Drift in the multiplexer may be detected by the computer when the output voltage limits, expected during normal operation, are exceeded, or the relationship defined by the calibration curve is invalidated.

  4. SSA Sensor Calibration Best Practices

    NASA Astrophysics Data System (ADS)

    Johnson, T.

    Best practices for calibrating orbit determination sensors in general and space situational awareness (SSA) sensors in particular are presented. These practices were developed over the last ten years within AGI and most recently applied to over 70 sensors in AGI's Commercial Space Operations Center (ComSpOC) and the US Air Force Space Command (AFSPC) Space Surveillance Network (SSN) to evaluate and configure new sensors and perform on-going system calibration. They are generally applicable to any SSA sensor and leverage some unique capabilities of an SSA estimation approach using an optimal sequential filter and smoother. Real world results are presented and analyzed.

  5. 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.

  6. 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).

  7. 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.

  8. 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.

  9. 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.

  10. Line-defect calibration for line-scanning projection display.

    PubMed

    An, Seungdo; Song, Jonghyeong; Lapchuk, Anatoliy; Yurlov, Victor; Ryu, Seung-Won; Kim, Eungju; Yun, Sang Kyeong

    2009-09-14

    A method of line-defect calibration for line-scanning projection display is developed to accomplish acceptable display uniformity. The line scanning display uses a line modulating imaging and scanning device to construct a two-dimensional image. The inherent line-defects in an imaging device and optical lenses are the most fatal performance-degrading factor that should be overcome to reach the basic display uniformity level. Since the human eye recognizes line defects very easily, a method that perfectly removes line defects is required. Most line imaging devices are diffractive optical devices that require a coherent light source. This particular requirement makes the calibration method of sequential single pixel measurement and correction insufficient to take out the line defects distributed on screen due to optical crosstalk. In this report, we present a calibration method using a recursively converging algorithm that successfully transforms the unacceptable line-defected images into a uniform display image. PMID:19770864

  11. IMU-based online kinematic calibration of robot manipulator.

    PubMed

    Du, Guanglong; Zhang, Ping

    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. Incompatible Ages for Clearwing Butterflies Based on Alternative Secondary Calibrations.

    PubMed

    Garzón-Orduña, Ivonne J; Silva-Brandão, Karina L; Willmott, Keith R; Freitas, André V L; Brower, Andrew V Z

    2015-09-01

    The recent publication of a time-tree for the plant family Solanaceae (nightshades) provides the opportunity to use independent calibrations to test divergence times previously inferred for the diverse Neotropical butterfly tribe Ithomiini. Ithomiini includes clades that are obligate herbivores of Solanaceae, with some genera feeding on only one genus. We used 8 calibrations extracted from the plant tree in a new relaxed molecular-clock analysis to produce an alternative temporal framework for the diversification of ithomiines. We compared the resulting age estimates to: (i) a time-tree obtained using 7 secondary calibrations from the Nymphalidae tree of Wahlberg et al. (2009), and (ii) Wahlberg et al.'s (2009) original age estimates for the same clades. We found that Bayesian clock estimates were rather sensitive to a variety of analytical parameters, including taxon sampling. Regardless of this sensitivity however, ithomiine divergence times calibrated with the ages of nightshades were always on average half the age of previous estimates. Younger dates for ithomiine clades appear to fit better with factors long suggested to have promoted diversification of the group such as the uplifting of the Andes, in the case of montane genera. Alternatively, if ithomiines are as old as previous estimates suggest, the recent ages inferred for the diversification of Solanaceae seem likely to be seriously underestimated. Our study exemplifies the difficulty of testing hypotheses of divergence times and of choosing between alternative dating scenarios, and shows that age estimates based on seemingly plausible calibrations may be grossly incongruent. PMID:26012872

  13. 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

  14. Calibration of NPP VIIRS fire detection band using lunar observations

    NASA Astrophysics Data System (ADS)

    McIntire, Jeff; Efremova, Boryana; Xiong, Xiaoxiong

    2012-09-01

    The National Polar-orbiting Partnership (NPP) Visible Infrared Imager Radiometer Suite (VIIRS) includes a fire detection band at roughly 4 ?m. This spectral band has two gain states; fire detection occurs in the low gain state above approximately 343 K. VIIRS thermal bands utilize an on-board blackbody to provide on-orbit calibration. However, as the maximum temperature of this blackbody is 315 K, the low gain state of the 4 ?m band cannot be calibrated in the same manner. Regular observations of the Moon provide an alternative calibration source, as the maximum surface temperature is around 390 K. The periodic on-board high gain calibration along with a surface temperature map based on LRO DIVINER observations was used to determine the emissivity and reflected radiance of the lunar surface at 4 ?m; these factors and the lunar data are then used to calibrate the low gain state of the fire band. Our analysis suggests that the responsivity of the low gain state is lower than the pre-launch value currently in use.

  15. 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.

  16. 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.

  17. 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...

  18. Cherenkov Source for PMT Calibrations

    NASA Astrophysics Data System (ADS)

    Kaptanoglu, Tanner; SNO+ at UC Berkeley Collaboration

    2013-10-01

    My research is focused on building a deployable source for PMT calibrations in the SNO+ detector. I work for the SNO+ group at UC Berkeley headed by Gabriel Orebi Gann. SNO+ is an addition to the SNO project, and its main goal is to search for neutrinoless double beta decay. The detector will be monitored by over 9500 photomultiplier tubes (PMTs). In order to characterize the PMTs, several calibration sources are being constructed. One of which, the Cherenkov Source, will provide a well-understood source of non-isotropic light for calibrating the detector response. My goal is to design and construct multiple aspects of the Cherenkov Source. However, there are multiple questions that arose with its design. How do we keep the scintillation light inside the Cherenkov source so it does not contaminate calibration? How do we properly build the Cherenkov source: a hollow acrylic sphere with a neck? Can we maintain a clean source throughout these processes? These are some of the problems I have been working on, and will continue to work on, until the deployment of the source. Additionally, I have worked to accurately simulate the physics inside the source, mainly the energy deposition of alphas.

  19. Autonomous Attitude Sensor Calibration (ASCAL)

    NASA Technical Reports Server (NTRS)

    Peterson, Chariya; Rowe, John; Mueller, Karl; Ziyad, Nigel

    1998-01-01

    In this paper, an approach to increase the degree of autonomy of flight software is proposed. We describe an enhancement of the Attitude Determination and Control System by augmenting it with self-calibration capability. Conventional attitude estimation and control algorithms are combined with higher level decision making and machine learning algorithms in order to deal with the uncertainty and complexity of the problem.

  20. Radiometric Self Calibration * Tomoo Mitsunaga

    E-print Network

    Nayar, Shree K.

    Radiometric Self Calibration * Tomoo Mitsunaga Media Processing Laboratories Sony Corporation mitsunag @av.crl.sony.co.jp Abstract A simple algorithm is described that computes the ra- diometric a David and Lucile Packard Fellowship. Tomoo Mitsunaga is supported by the Sony Cor- poration. 0

  1. 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...

  2. Christchurch field data for rockfall model calibration

    NASA Astrophysics Data System (ADS)

    Vick, L.; Glover, J.; Davies, T. R.

    2013-12-01

    The Canterbury earthquake of 2012-2011 triggered devastating rockfalls in the Port Hills in Christchurch, over 8000 boulders resulted in fatalities and severe building damage. There is a requirement for detailed and defensible rockfall hazard analysis to guide planning decisions in response to these rockfall events, most commonly this is performed with the use of a rockfall model. Calibrating a rockfall model requires a robust data set of past rockfall events. Information of rockfall deposit shape and size should be mapped over the affected area, in addition to information on the dynamics of the rockfall events such as jump heights and velocities of rocks. It is often the case that such information is obtained from expensive rock rolling studies; however the dynamics of an event can be estimated from the runout terrain and impact scars. In this study a calibration of a 3D rigid-body rockfall model was performed based on mapped boulder sizes and shapes over the rockfall affected zones of Christchurch, and estimations of boulder velocities gleaned from rock impact scars of individual trajectories and a high resolution digital terrain model produced following the rockfall events. The impact scars were mapped recording their length and depth of penetration into the loess soil cover of the runout zones. Two methods to estimate the boulder velocities have been applied. The first crudely estimates the velocity based on the vertical free fall potential between the rockfall shadow line and the terrain surface, and a velocity correction factor to account for friction. The second uses the impact scars assuming a parabolic trajectory between rock-ground impacts giving an indication of both jump height and velocity. Maximum runout distances produced a shadow angle of 23° in the area. Applying the first method suggests velocities can reach up to ~26 m s-1 and maxima concentrate in gullies and steep terrain. On average the distance between impact scars was 23 m, from which jump heights up to 4 m are estimated. While a first calibration of the rockfall model was possible by matching simulated to mapped deposit locations, many results initially showed unrealistic velocities and jump heights. The additional dynamic data has assisted in refining the calibration to ensure a defensible rockfall hazard analysis.

  3. 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

  4. Weighted least squares in calibration: estimating data variance functions in high-performance liquid chromatography.

    PubMed

    Zeng, Qiaoling Charlene; Zhang, Elizabeth; Dong, Hong; Tellinghuisen, Joel

    2008-10-10

    For minimum-variance estimation of parameters by the method of least squares, heteroscedastic data should be weighted inversely as their variance, w(i) proportional, variant 1/sigma(i)2. Here the instrumental data variance for a commercial high-performance liquid chromatography (HPLC) instrument is estimated from 5 to 11 replicate measurements on more than 20 samples for each of four different analytes. The samples span a range of over four orders of magnitude in concentration and HPLC peak area, over which the sampling variance estimates s2 are well represented as a sum of a constant term and a term proportional to the square of the peak area. The latter contribution is dominant over most of the range used in routine HPLC analysis and represents approximately 0.2% of peak area for all four analytes studied here. It includes a contribution from uncertainty in the syringe injection volume, which is found to be +/-0.008 microL. The dominance of proportional error justifies the use of 1/x2 or 1/y2 weighting in routine calibration with such data; however, the constant variance term means that these weighting formulas are not correct in the low-signal limit relevant for analysis at trace levels. Least-squares methods for both direct and logarithmic fitting of variance sampling estimates are described. Since such estimates themselves have proportional uncertainty, direct fitting requires iterative adjustment of the weights, while logarithmic fitting does not. PMID:18760790

  5. Revised absolute amplitude calibration of the LOPES experiment

    E-print Network

    K. Link; T. Huege; W. D. Apel; J. C. Arteaga-Velázquez; L. Bähren; K. Bekk; M. Bertaina; P. L. Biermann; J. Blümer; H. Bozdog; I. M. Brancus; E. Cantoni; A. Chiavassa; K. Daumiller; V. de Souza; F. Di Pierro; P. Doll; R. Engel; H. Falcke; B. Fuchs; H. Gemmeke; C. Grupen; A. Haungs; D. Heck; R. Hiller; J. R. Hörandel; A. Horneffer; D. Huber; P. G. Isar; K-H. Kampert; D. Kang; O. Krömer; J. Kuijpers; P. ?uczak; M. Ludwig; H. J. Mathes; M. Melissas; C. Morello; J. Oehlschläger; N. Palmieri; T. Pierog; J. Rautenberg; H. Rebel; M. Roth; C. Rühle; A. Saftoiu; H. Schieler; A. Schmidt; S. Schoo; F. G. Schröder; O. Sima; G. Toma; G. C. Trinchero; A. Weindl; J. Wochele; J. Zabierowski; J. A. Zensus

    2015-08-14

    One of the main aims of the LOPES experiment was the evaluation of the absolute amplitude of the radio signal of air showers. This is of special interest since the radio technique offers the possibility for an independent and highly precise determination of the energy scale of cosmic rays on the basis of signal predictions from Monte Carlo simulations. For the calibration of the amplitude measured by LOPES we used an external source. Previous comparisons of LOPES measurements and simulations of the radio signal amplitude predicted by CoREAS revealed a discrepancy of the order of a factor of two. A re-measurement of the reference calibration source, now performed for the free field, was recently performed by the manufacturer. The updated calibration values lead to a lowering of the reconstructed electric field measured by LOPES by a factor of $2.6 \\pm 0.2$ and therefore to a significantly better agreement with CoREAS simulations. We discuss the updated calibration and its impact on the LOPES analysis results.

  6. PISCES -- a computerized instrument calibration recall system

    SciTech Connect

    Adams, D.D.; Berry, D.O.; Gamble, M.M.

    1991-04-01

    This report discusses the Plant Instrumentation Surveillance, Calibration, and Evaluation System (PISCES). This data base system is used to keep track of calibration and functional testing of measuring instrumentation at the Hanford Site. (LSP)

  7. Recent Infrasound Calibration Activity at Los Alamos

    NASA Astrophysics Data System (ADS)

    Whitaker, R. W.; Marcillo, O. E.

    2014-12-01

    Absolute infrasound sensor calibration is necessary for estimating source sizes from measured waveforms. This can be an important function in treaty monitoring. The Los Alamos infrasound calibration chamber is capable of absolute calibration. Early in 2014 the Los Alamos infrasound calibration chamber resumed operations in its new location after an unplanned move two years earlier. The chamber has two sources of calibration signals. The first is the original mechanical piston, and the second is a CLD Dynamics Model 316 electro-mechanical unit that can be digitally controlled and provide a richer set of calibration options. During 2008-2010 a number of upgrades were incorporated for improved operation and recording. In this poster we give an overview of recent chamber work on sensor calibrations, calibration with the CLD unit, some measurements with different porous hoses and work with impulse sources.

  8. 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.

  9. 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.

  10. 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.

  11. Personal Social Network Factors Associated with Overdose Prevention Training Participation

    PubMed Central

    Iverson, Ellen; Wong, Carolyn F.; Jackson-Bloom, Jennifer; McNeeley, Miles; Davidson, Peter J.; McCarty, Christopher; Kral, Alex H.; Lankenau, Stephen E.

    2013-01-01

    We investigated social network factors associated with participation in overdose prevention training among injection drug users (IDUs). From 2008-2010, 106 IDUs who had witnessed an overdose in the past year from two syringe exchange programs in Los Angeles provided data on: overdose prevention training status (trained vs. untrained), social networks, history of overdose, and demographics. In multivariate logistic regression, naming at least one network member who had been trained in overdose prevention was significantly associated with being trained (Adjusted Odds Ratio 3.25, 95% Confidence Interval 1.09, 9.68). Using social network approaches may help increase training participation. Limitations are noted. PMID:22988840

  12. On the absolute calibration of SO2 cameras

    NASA Astrophysics Data System (ADS)

    Lübcke, P.; Bobrowski, N.; Illing, S.; Kern, C.; Alvarez Nieves, J. M.; Vogel, L.; Zielcke, J.; Delgado Granados, H.; Platt, U.

    2013-03-01

    Sulphur dioxide emission rate measurements are an important tool for volcanic monitoring and eruption risk assessment. The SO2 camera technique remotely measures volcanic emissions by analysing the ultraviolet absorption of SO2 in a narrow spectral window between 300 and 320 nm using solar radiation scattered in the atmosphere. The SO2 absorption is selectively detected by mounting band-pass interference filters in front of a two-dimensional, UV-sensitive CCD detector. One important step for correct SO2 emission rate measurements that can be compared with other measurement techniques is a correct calibration. This requires conversion from the measured optical density to the desired SO2 column density (CD). The conversion factor is most commonly determined by inserting quartz cells (cuvettes) with known amounts of SO2 into the light path. Another calibration method uses an additional narrow field-of-view Differential Optical Absorption Spectroscopy system (NFOV-DOAS), which measures the column density simultaneously in a small area of the camera's field-of-view. This procedure combines the very good spatial and temporal resolution of the SO2 camera technique with the more accurate column densities obtainable from DOAS measurements. This work investigates the uncertainty of results gained through the two commonly used, but quite different, calibration methods (DOAS and calibration cells). Measurements with three different instruments, an SO2 camera, a NFOV-DOAS system and an Imaging DOAS (I-DOAS), are presented. We compare the calibration-cell approach with the calibration from the NFOV-DOAS system. The respective results are compared with measurements from an I-DOAS to verify the calibration curve over the spatial extent of the image. The results show that calibration cells, while working fine in some cases, can lead to an overestimation of the SO2 CD by up to 60% compared with CDs from the DOAS measurements. Besides these errors of calibration, radiative transfer effects (e.g. light dilution, multiple scattering) can significantly influence the results of both instrument types. The measurements presented in this work were taken at Popocatépetl, Mexico, between 1 March 2011 and 4 March 2011. Average SO2 emission rates between 4.00 and 14.34 kg s-1 were observed.

  13. A practical method for sensor absolute calibration.

    PubMed

    Meisenholder, G W

    1966-04-01

    This paper describes a method of performing sensor calibrations using an NBS standard of spectral irradiance. The method shown, among others, was used for calibration of the Mariner IV Canopus sensor. Agreement of inflight response to preflight calibrations performed by this technique has been found to be well within 10%. PMID:20048890

  14. 14 CFR 33.45 - Calibration tests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Calibration tests. 33.45 Section 33.45... STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.45 Calibration tests. (a) Each engine must be subjected to the calibration tests necessary to establish its power characteristics...

  15. 14 CFR 33.45 - Calibration tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Calibration tests. 33.45 Section 33.45... STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.45 Calibration tests. (a) Each engine must be subjected to the calibration tests necessary to establish its power characteristics...

  16. 14 CFR 33.85 - Calibration tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Calibration tests. 33.85 Section 33.85... STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.85 Calibration tests. (a) Each engine must be subjected to those calibration tests necessary to establish its power characteristics and...

  17. 14 CFR 33.85 - Calibration tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Calibration tests. 33.85 Section 33.85... STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.85 Calibration tests. (a) Each engine must be subjected to those calibration tests necessary to establish its power characteristics and...

  18. 14 CFR 33.45 - Calibration tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Calibration tests. 33.45 Section 33.45... STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.45 Calibration tests. (a) Each engine must be subjected to the calibration tests necessary to establish its power characteristics...

  19. 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...

  20. Bayesian calibration of dynamic traffic simulations

    E-print Network

    Bierlaire, Michel

    for the calibration of microsimulation-based travel demand models in the context of dynamic traffic assignment (DTABayesian calibration of dynamic traffic simulations Gunnar Flötteröd Michel Bierlaire Kai Nagel present an operational framework for the calibration of demand models for dynamic traffic simulations. Our

  1. MODIS On-orbit Calibration Uncertainty Assessment

    NASA Technical Reports Server (NTRS)

    Chiang, Vincent; Sun, Junqiang; Wu, Aisheng

    2011-01-01

    MODIS has 20 reflective solar bands (RSB) and 16 thermal emissive bands (TEB). Compared to its heritage sensors, MODIS was developed with very stringent calibration uncertainty requirements. As a result, MODIS was designed and built with a set of on-board calibrators (OBC), which allow key sensor performance parameters and on-orbit calibration coefficients to be monitored and updated. 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 an in-depth analysis of its on-orbit calibration uncertainties. Also discussed in this paper are uncertainty contributions from individual components and differences due to Terra and Aqua MODIS instrument characteristics and on-orbit performance.

  2. 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.

  3. 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...

  4. 3D ULTRASOUND PROBE CALIBRATION WITHOUT A

    E-print Network

    Drummond, Tom

    to locate features accurately in 3D space. For 3D ultrasound reconstruction, errors in probe calibration3D ULTRASOUND PROBE CALIBRATION WITHOUT A POSITION SENSOR A. H. Gee, N. E. Houghton, G. M. Treece Ultrasound Probe Calibration Without a Position Sensor Andrew Gee, Neil Houghton, Graham Treece and Richard

  5. AUTOMATIC CALIBRATION OF A DISRIBUTED CATCHMENT MODEL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Parameters of hydrologic models often are not exactly known and therefore have to be determined by calibration. A manual calibration depends on the subjective assessment of the modeler and can be very time-consuming though. Methods of automatic calibration can improve these shortcomings. Yet, the...

  6. Supplemental material Humidity-isotope response calibration

    E-print Network

    Meskhidze, Nicholas

    Supplemental material Humidity-isotope response calibration Each individual analyzer needs [Aemisegger et al., 2012; Schmidt et al., 2010]. Without humidity calibration, varying humidity levels in the introduced air samples will introduce an artificial isotope signal. The humidity-isotope response calibration

  7. 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

    PubMed Central

    Davis, Corey S; Beletsky, Leo

    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 programs and may continue to treat the possession of injection equipment as illegal and program participation as a marker of illegal behavior. Law enforcement practice can impede SAP utilization and may increase the risk of needlestick injury (NSI) among law enforcement personnel. Many SAPs conduct little or no outreach to law enforcement, in part because they perceive law enforcement actors as unreceptive to health-promotion programs targeting drug users. Case description We report on a brief training intervention for law enforcement personnel designed to increase officer knowledge of and positive attitudes towards SAPs by bundling content that addresses officer concerns about infectious disease and occupational safety with information about the legality and public health benefits of these programs. Pilot trainings using this bundled curriculum were conducted with approximately 600 officers in three US cities. Discussion and evaluation Law enforcement officers were generally receptive to receiving information about SAPs through the bundled curriculum. The trainings led to better communication and collaboration between SAP and law enforcement personnel, providing a valuable platform for better harmonization of law enforcement and public health activities targeting injection drug users. Conclusion The experience in these three cities suggests that a harm reduction training curriculum that bundles strategies for increasing officer occupational safety with information about the legality and public health benefits of SAPs can be well received by law enforcement personnel and can lead to better communication and collaboration between law enforcement and harm reduction actors. Further study is indicated to assess whether such a bundled curriculum is effective in changing officer attitudes and beliefs and reducing health risks to officers and injection drug users, as well as broader benefits to the community at large. PMID:19602236

  8. The provision of non-needle/syringe drug injecting paraphernalia in the primary prevention of HCV among IDU: a systematic review

    PubMed Central

    2010-01-01

    Background Sharing drug injecting paraphernalia other than needles and syringes (N/S) has been implicated in the transmission of Hepatitis C virus (HCV) among injecting drug users (IDU). We aimed to determine whether the provision of sterile non-N/S injecting paraphernalia reduces injecting risk behaviours or HCV transmission among IDU. Methods A systematic search of seven databases and the grey literature for articles published January 1989-February 2010 was undertaken. Thirteen studies (twelve observational and one non-randomized uncontrolled pilot intervention) were identified and appraised for study design and quality by two investigators. Results No studies examined the association between the provision of non-N/S injecting paraphernalia and incident HCV infection. One cross-sectional study found that individuals who frequently, compared to those who infrequently, used sterile cookers and water, were less likely to report prevalent HCV infection. Another found no association between the uptake of sterile non-N/S injecting paraphernalia and self-reported sharing of this paraphernalia. The remaining observational studies used attendance at needle and syringe exchange programmes (NSP) or safer injection facilities (SIF) that provided non-N/S injecting paraphernalia as a proxy measure. Eight studies presented adjusted odds ratios, ranging from 0.3 to 0.9, suggesting a reduced likelihood of self-reported sharing of non-N/S injecting paraphernalia associated with use of NSP or SIF. There was substantial uncertainty associated with these estimates however. Three unadjusted studies reported a reduction in the prevalence of sharing of non-N/S injecting paraphernalia over time among NSP users. Only one study reported an adjusted temporal trend in the prevalence of sharing non-N/S injecting paraphernalia, finding higher rates among non-NSP users than NSP users at each time point, and a greater reduction in sharing among non-NSP than NSP users over time. Study limitations included the use of convenience samples, self-reported exposure and outcome measures, flawed classification of the exposed and unexposed groups, and inadequate adjustment for potential confounding variables. Conclusions The evidence to demonstrate that the provision of sterile non-N/S injecting paraphernalia reduces HCV transmission or modifies injecting risk behaviours is currently limited by an insufficient volume and quality of studies. Further research is required to inform practice and policy in this area. PMID:21092300

  9. A novel tantalum-based sol-gel packed microextraction syringe for highly specific enrichment of phosphopeptides in MALDI-MS applications.

    PubMed

    Çelikb?çak, Ömür; Atakay, Mehmet; Güler, Ülkü; Salih, Bekir

    2013-08-01

    A new tantalum-based sol-gel material was synthesized using a unique sol-gel synthesis pathway by PEG incorporation into the sol-gel structure without performing a calcination step. This improved its chemical and physical properties for the high capacity and selective enrichment of phosphopeptides from protein digests in complex biological media. The specificity of the tantalum-based sol-gel material for phosphopeptides was evaluated and compared with tantalum(V) oxide (Ta2O5) in different phosphopeptide enrichment applications. The tantalum-based sol-gel and tantalum(V) oxide were characterized in detail using FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM), and also using a surface area and pore size analyzer. In the characterization studies, the surface morphology, pore volume, crystallinity of the materials and PEG incorporation into the sol-gel structure to produce a more hydrophilic material were successfully demonstrated. The X-ray diffractograms of the two different materials were compared and it was noted that the broad signals of the tantalum-based sol-gel clearly represented the amorphous structure of the sol-gel material, which was more likely to create enough surface area and to provide more accessible tantalum atoms for phosphopeptides to be easily adsorbed when compared with the neat and more crystalline structure of Ta2O5. Therefore, the phosphopeptide enrichment performance of the tantalum-based sol-gels was found to be remarkably higher than the more crystalline Ta2O5 in our studies. Phosphopeptides at femtomole levels could be selectively enriched using the tantalum-based sol-gel and detected with a higher signal-to-noise ratio by matrix-assisted laser desorption/ionization-mass spectrometer (MALDI-MS). Moreover, phosphopeptides in a tryptic digest of non-fat bovine milk as a complex real-world biological sample were retained with higher yield using a tantalum-based sol-gel. Additionally, the sol-gel material was packed into a standard syringe (0.5 mL) to enhance the ease of use of the sol-gel material and for the elimination of additional mixing and separation procedures during the adsorption, washing and elution steps of the enrichment procedure. It was found that up to 28 phosphopeptides in milk digest were easily detectable by MALDI-MS at femtomole levels (around 20 fmol) using the microextraction syringe within less than one minute. PMID:23730683

  10. Thermal Targets for Satellite Calibration

    SciTech Connect

    Villa-Aleman, E.

    2001-01-10

    The Savannah River Technology Center (SRTC) is currently calibrating the Multispectral Thermal Imager (MTI) satellite sponsored by the Department of Energy. The MTI imager is a research and development project with 15 wavebands in the visible, near-infrared, short-wave infrared, mid-wave infrared and long-wave infrared spectral regions. A plethora of targets with known temperatures such as power plant heated lakes, volcano lava vents, desert playas and aluminized Mylar tarps are being used in the validation of the five thermal bands of the MTI satellite. SRTC efforts in the production of ''cold targets'' with aluminized Mylar tarps will be described. Visible and thermal imagery and wavelength dependent radiance measurements of the calibration targets will be presented.

  11. Toward Millimagnitude Photometric Calibration (Abstract)

    NASA Astrophysics Data System (ADS)

    Dose, E.

    2014-12-01

    (Abstract only) Asteroid roation, exoplanet transits, and similar measurements will increasingly call for photometric precisions better than about 10 millimagnitudes, often between nights and ideally between distant observers. The present work applies detailed spectral simulations to test popular photometric calibration practices, and to test new extensions of these practices. Using 107 synthetic spectra of stars of diverse colors, detailed atmospheric transmission spectra computed by solar-energy software, realistic spectra of popular astronomy gear, and the option of three sources of noise added at realistic millimagnitude levels, we find that certain adjustments to current calibration practices can help remove small systematic errors, especially for imperfect filters, high airmasses, and possibly passing thin cirrus clouds.

  12. Spinning angle optical calibration apparatus

    DOEpatents

    Beer, Stephen K. (Morgantown, WV); Pratt, II, Harold R. (Morgantown, WV)

    1991-01-01

    An optical calibration apparatus is provided for calibrating and reproducing spinning angles in cross-polarization, nuclear magnetic resonance spectroscopy. An illuminated magnifying apparatus enables optical setting an accurate reproducing of spinning "magic angles" in cross-polarization, nuclear magnetic resonance spectroscopy experiments. A reference mark scribed on an edge of a spinning angle test sample holder is illuminated by a light source and viewed through a magnifying scope. When the "magic angle" of a sample material used as a standard is attained by varying the angular position of the sample holder, the coordinate position of the reference mark relative to a graduation or graduations on a reticle in the magnifying scope is noted. Thereafter, the spinning "magic angle" of a test material having similar nuclear properties to the standard is attained by returning the sample holder back to the originally noted coordinate position.

  13. Automated Camera Array Fine Calibration

    NASA Technical Reports Server (NTRS)

    Clouse, Daniel; Padgett, Curtis; Ansar, Adnan; Cheng, Yang

    2008-01-01

    Using aerial imagery, the JPL FineCalibration (JPL FineCal) software automatically tunes a set of existing CAHVOR camera models for an array of cameras. The software finds matching features in the overlap region between images from adjacent cameras, and uses these features to refine the camera models. It is not necessary to take special imagery of a known target and no surveying is required. JPL FineCal was developed for use with an aerial, persistent surveillance platform.

  14. ASCAL: Autonomous Attitude Sensor Calibration

    NASA Technical Reports Server (NTRS)

    Peterson, Chariya; Rowe, John; Mueller, Karl; Ziyad, Nigel

    1999-01-01

    Abstract In this paper, an approach to increase the degree of autonomy of flight software is proposed. We describe an enhancement of the Attitude Determination and Control System by augmenting it with self-calibration capability. Conventional attitude estimation and control algorithms are combined with higher level decision making and machine learning algorithms in order to deal with the uncertainty and complexity of the problem.

  15. Mars Exploration Rover Navigation Camera in-flight calibration

    USGS Publications Warehouse

    Soderblom, J.M.; Bell, J.F., III; Johnson, J.R.; Joseph, J.; Wolff, M.J.

    2008-01-01

    The Navigation Camera (Navcam) instruments on the Mars Exploration Rover (MER) spacecraft provide support for both tactical operations as well as scientific observations where color information is not necessary: large-scale morphology, atmospheric monitoring including cloud observations and dust devil movies, and context imaging for both the thermal emission spectrometer and the in situ instruments on the Instrument Deployment Device. The Navcams are a panchromatic stereoscopic imaging system built using identical charge-coupled device (CCD) detectors and nearly identical electronics boards as the other cameras on the MER spacecraft. Previous calibration efforts were primarily focused on providing a detailed geometric calibration in line with the principal function of the Navcams, to provide data for the MER navigation team. This paper provides a detailed description of a new Navcam calibration pipeline developed to provide an absolute radiometric calibration that we estimate to have an absolute accuracy of 10% and a relative precision of 2.5%. Our calibration pipeline includes steps to model and remove the bias offset, the dark current charge that accumulates in both the active and readout regions of the CCD, and the shutter smear. It also corrects pixel-to-pixel responsivity variations using flat-field images, and converts from raw instrument-corrected digital number values per second to units of radiance (W m-2 nm-1 sr-1), or to radiance factor (I/F). We also describe here the initial results of two applications where radiance-calibrated Navcam data provide unique information for surface photometric and atmospheric aerosol studies. Copyright 2008 by the American Geophysical Union.

  16. Updated Calibration and Backgrounds for the WFC3 IR Grisms

    NASA Astrophysics Data System (ADS)

    Pirzkal, Norbert; Brammer, Gabriel; Ryan, Russell E.

    2015-01-01

    We present new and improved calibration of the WFC IR (G102 and G141) grism mode. These new calibrations were generated by combining data obtained over six observing cycles and include a better sampling of the field of view. The result is a calibration of the spectral trace that has been improved to better than 0.1 detector pixel. A new fiducial wavelength reference spectrum is now used to calibrate the wavelength dispersion of the grisms and we show that the rms of the solution has been reduced to approximately 7 and 14 Angstrom for the G102 and G141 grisms, over the entire field of view. Overall, both the trace and wavelength calibration have been improved by about a factor of two and the G102 and G141 solutions are in better agreement at wavelengths where the two grisms overlap. We demonstrate that the grism calibration can be extrapolated for objects that are outside of the field of view but still result in dispersed spectra on the WFC3 detector.We also present new master sky images that can be used to improve the sky background subtraction from grism exposures. The individual components of the new background model include the zodiacal continuum and a strong He I emission line at 1.083 microns from the upper atmosphere. We find that fitting science exposures with a linear combination of these two background components enables modeling of the WFC3/IR grism background with an accuracy that is better than ~0.01 electrons/s/pix across the detector.

  17. PACS photometer calibration block analysis

    NASA Astrophysics Data System (ADS)

    Moór, A.; Müller, T. G.; Kiss, C.; Balog, Z.; Billot, N.; Marton, G.

    2014-07-01

    The absolute stability of the PACS bolometer response over the entire mission lifetime without applying any corrections is about 0.5 % (standard deviation) or about 8 % peak-to-peak. This fantastic stability allows us to calibrate all scientific measurements by a fixed and time-independent response file, without using any information from the PACS internal calibration sources. However, the analysis of calibration block observations revealed clear correlations of the internal source signals with the evaporator temperature and a signal drift during the first half hour after the cooler recycling. These effects are small, but can be seen in repeated measurements of standard stars. From our analysis we established corrections for both effects which push the stability of the PACS bolometer response to about 0.2 % (stdev) or 2 % in the blue, 3 % in the green and 5 % in the red channel (peak-to-peak). After both corrections we still see a correlation of the signals with PACS FPU temperatures, possibly caused by parasitic heat influences via the Kevlar wires which connect the bolometers with the PACS Focal Plane Unit. No aging effect or degradation of the photometric system during the mission lifetime has been found.

  18. Protocols for calibrating multibeam sonar.

    PubMed

    Foote, Kenneth G; Chu, Dezhang; Hammar, Terence R; Baldwin, Kenneth C; Mayer, Larry A; Hufnagle, Lawrence C; Jech, J Michael

    2005-04-01

    Development of protocols for calibrating multibeam sonar by means of the standard-target method is documented. Particular systems used in the development work included three that provide the water-column signals, namely the SIMRAD SM2000/90- and 200-kHz sonars and RESON SeaBat 8101 sonar, with operating frequency of 240 kHz. Two facilities were instrumented specifically for the work: a sea well at the Woods Hole Oceanographic Institution and a large, indoor freshwater tank at the University of New Hampshire. Methods for measuring the transfer characteristics of each sonar, with transducers attached, are described and illustrated with measurement results. The principal results, however, are the protocols themselves. These are elaborated for positioning the target, choosing the receiver gain function, quantifying the system stability, mapping the directionality in the plane of the receiving array and in the plane normal to the central axis, measuring the directionality of individual beams, and measuring the nearfield response. General preparations for calibrating multibeam sonars and a method for measuring the receiver response electronically are outlined. Advantages of multibeam sonar calibration and outstanding problems, such as that of validation of the performance of multibeam sonars as configured for use, are mentioned. PMID:15898644

  19. Model Calibration in Watershed Hydrology

    NASA Technical Reports Server (NTRS)

    Yilmaz, Koray K.; Vrugt, Jasper A.; Gupta, Hoshin V.; Sorooshian, Soroosh

    2009-01-01

    Hydrologic models use relatively simple mathematical equations to conceptualize and aggregate the complex, spatially distributed, and highly interrelated water, energy, and vegetation processes in a watershed. A consequence of process aggregation is that the model parameters often do not represent directly measurable entities and must, therefore, be estimated using measurements of the system inputs and outputs. During this process, known as model calibration, the parameters are adjusted so that the behavior of the model approximates, as closely and consistently as possible, the observed response of the hydrologic system over some historical period of time. This Chapter reviews the current state-of-the-art of model calibration in watershed hydrology with special emphasis on our own contributions in the last few decades. We discuss the historical background that has led to current perspectives, and review different approaches for manual and automatic single- and multi-objective parameter estimation. In particular, we highlight the recent developments in the calibration of distributed hydrologic models using parameter dimensionality reduction sampling, parameter regularization and parallel computing.

  20. Genetic Algorithm Calibration of Probabilistic Cellular Automata for Modeling Mining Permit Activity

    USGS Publications Warehouse

    Louis, S.J.; Raines, G.L.

    2003-01-01

    We use a genetic algorithm to calibrate a spatially and temporally resolved cellular automata to model mining activity on public land in Idaho and western Montana. The genetic algorithm searches through a space of transition rule parameters of a two dimensional cellular automata model to find rule parameters that fit observed mining activity data. Previous work by one of the authors in calibrating the cellular automaton took weeks - the genetic algorithm takes a day and produces rules leading to about the same (or better) fit to observed data. These preliminary results indicate that genetic algorithms are a viable tool in calibrating cellular automata for this application. Experience gained during the calibration of this cellular automata suggests that mineral resource information is a critical factor in the quality of the results. With automated calibration, further refinements of how the mineral-resource information is provided to the cellular automaton will probably improve our model.

  1. Improvement of Accuracy in Environmental Dosimetry by TLD Cards Using Three-dimensional Calibration Method

    PubMed Central

    HosseiniAliabadi, S. J.; Hosseini Pooya, S. M.; Afarideh, H.; Mianji, F.

    2015-01-01

    Introduction The angular dependency of response for TLD cards may cause deviation from its true value on the results of environmental dosimetry, since TLDs may be exposed to radiation at different angles of incidence from the surrounding area. Objective A 3D setting of TLD cards has been calibrated isotropically in a standard radiation field to evaluate the improvement of the accuracy of measurement for environmental dosimetry. Method Three personal TLD cards were rectangularly placed in a cylindrical holder, and calibrated using 1D and 3D calibration methods. Then, the dosimeter has been used simultaneously with a reference instrument in a real radiation field measuring the accumulated dose within a time interval. Result The results show that the accuracy of measurement has been improved by 6.5% using 3D calibration factor in comparison with that of normal 1D calibration method. Conclusion This system can be utilized in large scale environmental monitoring with a higher accuracy. PMID:26157729

  2. Photometric Calibrations for the SIRTF Infrared Spectrograph

    E-print Network

    P. W. Morris; V. Charmandaris; T. Herter; L. Armus; J. Houck; G. Sloan

    2002-03-07

    The SIRTF InfraRed Spectrograph (IRS) is faced with many of the same calibration challenges that were experienced in the ISO SWS calibration program, owing to similar wavelength coverage and overlapping spectral resolutions of the two instruments. Although the IRS is up to ~300 times more sensitive and without moving parts, imposing unique calibration challenges on their own, an overlap in photometric sensitivities of the high-resolution modules with the SWS grating sections allows lessons, resources, and certain techniques from the SWS calibration programs to be exploited. We explain where these apply in an overview of the IRS photometric calibration planning.

  3. Scatterometer-Calibrated Stability Verification Method

    NASA Technical Reports Server (NTRS)

    McWatters, Dalia A.; Cheetham, Craig M.; Huang, Shouhua; Fischman, Mark A.; CHu, Anhua J.; Freedman, Adam P.

    2011-01-01

    The requirement for scatterometer-combined transmit-receive gain variation knowledge is typically addressed by sampling a portion of the transmit signal, attenuating it with a known-stable attenuation, and coupling it into the receiver chain. This way, the gain variations of the transmit and receive chains are represented by this loop-back calibration signal, and can be subtracted from the received remote radar echo. Certain challenges are presented by this process, such as transmit and receive components that are outside of this loop-back path and are not included in this calibration, as well as the impracticality for measuring the transmit and receive chains stability and post fabrication separately, without the resulting measurement errors from the test set up exceeding the requirement for the flight instrument. To cover the RF stability design challenge, the portions of the scatterometer that are not calibrated by the loop-back, (e.g., attenuators, switches, diplexers, couplers, and coaxial cables) are tightly thermally controlled, and have been characterized over temperature to contribute less than 0.05 dB of calibration error over worst-case thermal variation. To address the verification challenge, including the components that are not calibrated by the loop-back, a stable fiber optic delay line (FODL) was used to delay the transmitted pulse, and to route it into the receiver. In this way, the internal loopback signal amplitude variations can be compared to the full transmit/receive external path, while the flight hardware is in the worst-case thermal environment. The practical delay for implementing the FODL is 100 s. The scatterometer pulse width is 1 ms so a test mode was incorporated early in the design phase to scale the 1 ms pulse at 100-Hz pulse repetition interval (PRI), by a factor of 18, to be a 55 s pulse with 556 s PRI. This scaling maintains the duty cycle, thus maintaining a representative thermal state for the RF components. The FODL consists of an RF-modulated fiber-optic transmitter, 20 km SMF- 28 standard single-mode fiber, and a photodetector. Thermoelectric cooling and insulating packaging are used to achieve high thermal stability of the FODL components. The chassis was insulated with 1-in. (.2.5-cm) thermal isolation foam. Nylon rods support the Micarta plate, onto which are mounted four 5-km fiber spool boxes. A copper plate heat sink was mounted on top of the fiber boxes (with thermal grease layer) and screwed onto the thermoelectric cooler plate. Another thermal isolation layer in the middle separates the fiberoptics chamber from the RF electronics components, which are also mounted on a copper plate that is screwed onto another thermoelectric cooler. The scatterometer subsystem fs overall stability was successfully verified to be calibratable to within 0.1 dB error in thermal vacuum (TVAC) testing with the fiber-optic delay line, while the scatterometer temperature was ramped from 10 to 30 C, which is a much larger temperature range than the worst-case expected seasonal variations.

  4. Muon Energy Calibration of the MINOS Detectors

    SciTech Connect

    Miyagawa, Paul S.

    2004-09-01

    MINOS is a long-baseline neutrino oscillation experiment designed to search for conclusive evidence of neutrino oscillations and to measure the oscillation parameters precisely. MINOS comprises two iron tracking calorimeters located at Fermilab and Soudan. The Calibration Detector at CERN is a third MINOS detector used as part of the detector response calibration programme. A correct energy calibration between these detectors is crucial for the accurate measurement of oscillation parameters. This thesis presents a calibration developed to produce a uniform response within a detector using cosmic muons. Reconstruction of tracks in cosmic ray data is discussed. This data is utilized to calculate calibration constants for each readout channel of the Calibration Detector. These constants have an average statistical error of 1.8%. The consistency of the constants is demonstrated both within a single run and between runs separated by a few days. Results are presented from applying the calibration to test beam particles measured by the Calibration Detector. The responses are calibrated to within 1.8% systematic error. The potential impact of the calibration on the measurement of oscillation parameters by MINOS is also investigated. Applying the calibration reduces the errors in the measured parameters by {approx} 10%, which is equivalent to increasing the amount of data by 20%.

  5. Size of spectroscopic calibration samples for cosmic shear photometric redshifts

    E-print Network

    Zhaoming Ma; Gary Bernstein

    2008-09-07

    Weak gravitational lensing surveys using photometric redshifts can have their cosmological constraints severely degraded by errors in the photo-z scale. We explore the cosmological degradation vs the size of the spectroscopic survey required to calibrate the photo-z probability distribution. Previous work has assumed a simple Gaussian distribution of photo-z errors; here we describe a method for constraining an arbitrary parametric photo-z error model. As an example we allow the photo-z probability distribution to be the sum of $N_g$ Gaussians. To limit cosmological degradation to a fixed level, photo-z models with multiple Gaussians require up to 5 times larger calibration sample than one would estimate from assuming a single-Gaussian model. This degradation saturates at $N_g\\approx 4$. Assuming a single Gaussian when the photo-z distribution has multiple parameters underestimates cosmological parameter uncertainties by up to 35%. The size of required calibration sample also depends upon the shape of the fiducial distribution, even when the RMS photo-z error is held fixed. The required calibration sample size varies up to a factor of 40 among the fiducial models studied, but this is reduced to a factor of a few if the photo-z parameters are forced to be slowly varying with redshift. Finally we show that the size of the required calibration sample can be substantially reduced by optimizing its redshift distribution. We hope this study will help stimulate work on better understanding of photo-z errors.

  6. Calibration of a novel four-dimensional diode array

    SciTech Connect

    Yan Guanghua; Lu Bo; Kozelka, Jakub; Liu, Chihray; Li, Jonathan G.

    2010-01-15

    Purpose: The aim of this work is to develop effective calibration methods for a novel four-dimensional (4D) diode array for pretreatment verification of intensity-modulated radiation therapy (IMRT) and rotational therapy. Methods: A novel 4D diode array (ArcCHECK, Sun Nuclear, Melbourne, FL) was developed to meet the needs of appropriate and efficient quality assurance for IMRT and especially rotational radiotherapy. The diode array presents a consistent detector image in beam's eye view at arbitrary gantry angles due to isotropic arrangement of diodes in a three-dimensional (3D) cylindrical phantom. The 50 ms simultaneous update of all diodes on the detector array (fourth dimension) makes it capable of time-resolved beam delivery analysis with any rotational delivery techniques. The calibration procedure consisted of delivering and measuring a series of calibration beams with 5.8 deg. angular spacing surrounding the cylindrical diode array. Correction factors for diode intrinsic sensitivity and directional response dependence were derived from these measurements. A real-time algorithm to derive gantry angles based on the detector signal was developed to interpolate and apply the corresponding angular correction factors. Results: The calibration was validated with ion chamber scanned beam profiles in a 3D water tank. Excellent agreement was observed between diode array measurement and treatment planning system calculation. The accuracy of the gantry angle derivation algorithm was within 1 deg. which caused a less than 0.2% dosimetric uncertainty. Conclusions: With the proposed calibration method and the automatic gantry angle derivation algorithm, the 4D diode array achieved isotropic detector response and is suitable for both IMRT and rotational therapy pretreatment verification.

  7. MODIS Instrument Operation and Calibration Improvements

    NASA Technical Reports Server (NTRS)

    Xiong, X.; Angal, A.; Madhavan, S.; Link, D.; Geng, X.; Wenny, B.; Wu, A.; Chen, H.; Salomonson, V.

    2014-01-01

    Terra and Aqua MODIS have successfully operated for over 14 and 12 years since their respective launches in 1999 and 2002. The MODIS on-orbit calibration is performed using a set of on-board calibrators, which include a solar diffuser for calibrating the reflective solar bands (RSB) and a blackbody for the thermal emissive bands (TEB). On-orbit changes in the sensor responses as well as key performance parameters are monitored using the measurements of these on-board calibrators. This paper provides an overview of MODIS on-orbit operation and calibration activities, and instrument long-term performance. It presents a brief summary of the calibration enhancements made in the latest MODIS data collection 6 (C6). Future improvements in the MODIS calibration and their potential applications to the S-NPP VIIRS are also discussed.

  8. Multi-Axis Accelerometer Calibration System

    NASA Technical Reports Server (NTRS)

    Finley, Tom; Parker, Peter

    2010-01-01

    A low-cost, portable, and simplified system has been developed that is suitable for in-situ calibration and/or evaluation of multi-axis inertial measurement instruments. This system overcomes facility restrictions and maintains or improves the calibration quality for users of accelerometer-based instruments with applications in avionics, experimental wind tunnel research, and force balance calibration applications. The apparatus quickly and easily positions a multi-axis accelerometer system into a precisely known orientation suitable for in-situ quality checks and calibration. In addition, the system incorporates powerful and sophisticated statistical methods, known as response surface methodology and statistical quality control. These methods improve calibration quality, reduce calibration time, and allow for increased calibration frequency, which enables the monitoring of instrument stability over time.

  9. Development of a programmable piggyback syringe pump and four-times-a-day injection regimen for superovulation in non-lactating Holstein cows.

    PubMed

    Irshad, Abdul Razaq; Sasaki, Taihei; Kubo, Tomoaki; Odashima, Naoyuki; Katano, Keiji; Osawa, Takeshi; Takahashi, Toru; Izaike, Yoshiaki

    2015-10-21

    The objectives of the present study were to develop a programmable piggyback syringe pump for bovine superovulation and to evaluate the effects of a four-times-a-day injection regimen using the pump. Non-lactating Holstein cows were treated with a total of 30 armour units of porcine FSH by injection four times a day with the pump (study, n = 9) or injection twice a day manually (control, n = 9) for four consecutive days from D10 of the estrous cycle. The pump-driven program successfully induced superovulation in all cows tested. The numbers of small (3- < 5 mm in diameter) and large (? 10 mm in diameter) follicles were greater in the study group on D11-13 and D14, respectively. There were fewer unovulated follicles detected on D21 (7 days after estrus) in the study group than in the control group (1.2 ± 0.4 and 3.2 ± 0.6, respectively). PMID:26052155

  10. Barriers and Potential Improvements for Needle and Syringe Exchange Programs (NSPs) in China: A Qualitative Study from Perspectives of Both Health and Public Security Sectors

    PubMed Central

    Chow, Eric P. F.; Jing, Jun; Zheng, Jun; Zhao, Junshi; Zhang, Lei

    2015-01-01

    This study explores the acceptability, the barriers to the implementation of needle and syringe exchange programs (NSPs) and the potential improvement strategies in China from the perspectives of governmental health and public security officials. Purposive sampling was used for recruitment of participants who had been involved in NSPs implementation. Semi-Structured individual interviews were conducted in Mandarin to address three aspects of NSPs: (1) participants’ attitudes towards NSPs, (2) participants’ opinions on the effectiveness and barriers of NSPs, and (3) suggestions for improving the program. Content analysis was used to analyse the translated interview data. A total of 68 participants from 12 Hunan counties were interviewed (34 from each of the Bureau of Health and the Narcotic Division). Both groups recognised the importance and effectiveness of NSPs in HIV prevention, but public security officials regarded NSPs as a temporary intervention in place of punitive measures. Most health officials (32/34) regarded the main barriers to its implementation as administrative and structural, whereas participants from Narcotics Division (n=24) questioned the legitimacy of NSPs and concerned about the poor management of drug users’ risk behaviours. Close cooperation between the health and public security sectors, engagement of the drug user community and an enabling policy environment were reportedly to be critical for potential improvements of NSPs in China. Misconceptions about NSPs encourage drug users’ addictive behaviour, and an unclear leadership and insufficient support de-motivate the participants from the Bureau of Health and the Narcotics Division to actively support the program implementation. PMID:26114556

  11. Development of a programmable piggyback syringe pump and four-times-a-day injection regimen for superovulation in non-lactating Holstein cows

    PubMed Central

    IRSHAD, Abdul Razaq; SASAKI, Taihei; KUBO, Tomoaki; ODASHIMA, Naoyuki; KATANO, Keiji; OSAWA, Takeshi; TAKAHASHI, Toru; IZAIKE, Yoshiaki

    2015-01-01

    The objectives of the present study were to develop a programmable piggyback syringe pump for bovine superovulation and to evaluate the effects of a four-times-a-day injection regimen using the pump. Non-lactating Holstein cows were treated with a total of 30 armour units of porcine FSH by injection four times a day with the pump (study, n = 9) or injection twice a day manually (control, n = 9) for four consecutive days from D10 of the estrous cycle. The pump-driven program successfully induced superovulation in all cows tested. The numbers of small (3– < 5 mm in diameter) and large (? 10 mm in diameter) follicles were greater in the study group on D11-13 and D14, respectively. There were fewer unovulated follicles detected on D21 (7 days after estrus) in the study group than in the control group (1.2 ± 0.4 and 3.2 ± 0.6, respectively). PMID:26052155

  12. Providing radiometric traceability for the calibration home base of DLR by PTB

    SciTech Connect

    Taubert, D. R.; Hollandt, J.; Sperfeld, P.; Pape, S.; Hoepe, A.; Hauer, K.-O.; Gege, P.; Schwarzmaier, T.; Lenhard, K.; Baumgartner, A.

    2013-05-10

    A dedicated calibration technique was applied for the calibration of the spectral radiance transfer standard (RASTA) of the German Aerospace Center (DLR) at the Physikalisch-Technische Bundesanstalt (PTB), consisting of two independent but complementing calibration procedures to provide redundancy and smallest possible calibration uncertainties. Procedure I included two calibration steps: In a first step the optical radiation source of RASTA, an FEL lamp, was calibrated in terms of its spectral irradiance E{sub {lambda}}({lambda}) in the wavelength range from 350 nm to 2400 nm using the PTB Spectral Irradiance Calibration Equipment (SPICE), while in a second step the spectral radiance factor {beta}{sub 0 Degree-Sign :45 Degree-Sign }({lambda}) of the RASTA reflection standard was calibrated in a 0 Degree-Sign :45 Degree-Sign -viewing geometry in the wavelength range from 350 nm to 1700 nm at the robot-based gonioreflectometer facility of PTB. The achieved relative standard uncertainties (k= 1) range from 0.6 % to 3.2 % and 0.1 % to 0.6 % respectively. Procedure II was completely independent from procedure I and allowed to cover the entire spectral range of RASTA from 350 nm to 2500 nm. In the second procedure, the 0 Degree-Sign :45 Degree-Sign -viewing geometry spectral radiance L{sub {lambda},0 Degree-Sign :45 Degree-Sign }({lambda}) of RASTA was directly calibrated at the Spectral Radiance Comparator Facility (SRCF) of PTB. The relative uncertainties for this calibration procedure range from 0.8 % in the visible up to 7.5 % at 2500 nm (k= 1). In the overlapping spectral range of both calibration procedures the calculated spectral radiance L{sub {lambda},0 Degree-Sign :45 Degree-Sign ,calc}({lambda}) from procedure I is in good agreement with the direct measurement of procedure II, i.e. well within the combined expanded uncertainties (k= 2) of both procedures.

  13. Dry calibration of electromagnetic flowmeters based on numerical models combining multiple physical phenomena (multiphysics)

    SciTech Connect

    Fu, X.; Hu, L.; Zou, J.; Ruan, X. D.; Yang, H. Y.; Lee, K. M.

    2010-10-15

    This paper presents a method for dry calibration of an electromagnetic flowmeter (EMF). This method, which determines the voltage induced in the EMF as conductive liquid flows through a magnetic field, numerically solves a coupled set of multiphysical equations with measured boundary conditions for the magnetic, electric, and flow fields in the measuring pipe of the flowmeter. Specifically, this paper details the formulation of dry calibration and an efficient algorithm (that adaptively minimizes the number of measurements and requires only the normal component of the magnetic flux density as boundary conditions on the pipe surface to reconstruct the magnetic field involved) for computing the sensitivity of EMF. Along with an in-depth discussion on factors that could significantly affect the final precision of a dry calibrated EMF, the effects of flow disturbance on measuring errors have been experimentally studied by installing a baffle at the inflow port of the EMF. Results of the dry calibration on an actual EMF were compared against flow-rig calibration; excellent agreements (within 0.3%) between dry calibration and flow-rig tests verify the multiphysical computation of the fields and the robustness of the method. As requiring no actual flow, the dry calibration is particularly useful for calibrating large-diameter EMFs where conventional flow-rig methods are often costly and difficult to implement.

  14. Calibration Report for the WRAP Facility Gamma Energy Analysis System (104-ND-06-102A)

    SciTech Connect

    WILLS, C.E.

    2000-03-13

    The Waste Receiving And Processing facility (WRAP) adheres to providing gamma-ray spectroscopy instrument calibrations traceable to the National Institute for Standards and Technology (NIST) standard{sup (4)}. The detectors are used to produce quantitative results for the Waste Isolation Pilot Plant (WIPP) and must meet calibration programmatic calibration goals. Instruments must meet portions of ANSI N42.14, 1978 guide for Germanium detectors. The Non-Destructive Assay (NDA) Gamma Energy Analysis (GEA) utilizes NIST traceable line source standards for the detector system calibrations. The counting configuration is a series of drums containing the line sources and different density filler matrices. The drums are used to develop system efficiencies with respect to density. The efficiency and density correction factors are required for the processing of drummed waste materials of similar densities. The calibration verification is carried out after the calibration is deemed final, by counting a second drum of NIST traceable sources. Three in-depth calibrations have been completed on one of the two systems to date, the first being the system acceptance plan. This report has a secondary function; that being the development of the instrument calibration errors which are to be folded into the Total Instrument Uncertainty document, HNF-4050.

  15. Calibration Report for the WRAP Facility Gamma Energy Analysis System [104-ND-06-102A

    SciTech Connect

    WILLS, C.E.

    2000-02-15

    The Waste Receiving And Processing facility (WRAP) adheres to providing gamma-ray spectroscopy instrument calibrations traceable to the National Institute for Standards and Technology (NIST) standards. The detectors are used to produce quantitative results for the Waste Isolation Pilot Plant (WIPP) and must meet calibration programmatic calibration goals. Instruments must meet portions of ANSI N42.14, 1978 guide for Germanium detectors. The Non-Destructive Assay (NDA) Gamma Energy Analysis (GEA) utilizes NIST traceable line source standards for the detector system calibrations. The counting configuration is a series of drums containing the line sources and different density filler matrices. The drums are used to develop system efficiencies with respect to density. The efficiency and density correction factors are required for the processing of drummed waste materials of similar densities. The calibration verification is carried out after the calibration is deemed final, by counting a second drum of NIST traceable sources. Three in-depth calibrations have been completed on one of the two systems to date, the first being the system acceptance plan. This report has a secondary function; that being the development of the instrument calibration errors which are to be folded into the Total Instrument Uncertainty document, HNF-4050.

  16. Effects of pressurization procedures on calibration results for precise pressure transducers

    NASA Astrophysics Data System (ADS)

    Kajikawa, Hiroaki; Kobata, Tokihiko

    2010-06-01

    The output of electromechanical pressure gauges depends on not only the currently applied pressure, but also the pressurization history. Thus, the calibration results of gauges are affected by the pressurization procedure. In this paper, among several important factors influencing the results, we report the effects of the interval between the calibration cycles and the effects of the preliminary pressurizations. In order to quantitatively evaluate these effects, we developed a fully automated system that uses a pressure balance to calibrate pressure gauges. Subsequently, gauges containing quartz Bourdon-type pressure transducers were calibrated in a stepwise manner for pressures between 10 MPa and 100 MPa. The typical standard deviation of the data over three cycles was reduced to a few parts per million (ppm). The interval between the calibration cycles, which ranges from zero to more than 12 h, exerts a strong influence on the results in the process of increasing the pressure, where at 10 MPa the maximum difference between the results was approximately 40 ppm. The preliminary pressurization immediately before the calibration cycle reduces the effects of the interval on the results in certain cases. However, in turn, the influence of the waiting time between the preliminary pressurization and the main calibration cycle becomes strong. In the present paper, we outline several possible measures for obtaining calibration results with high reproducibility.

  17. Calibrating automatic exposure control devices for digital radiography

    NASA Astrophysics Data System (ADS)

    Doyle, P.; Martin, C. J.

    2006-11-01

    The energy responses of digital radiography detectors differ from those of screen-film systems. To provide a consistent level of image quality at different tube potentials automatic exposure control (AEC) devices must be calibrated to suit the energy response of the image receptor with which they are intended for use. AEC calibration for digital radiography systems requires an alternative parameter to optical density, ideally one related to the quality of a digital image. Energy responses of computed radiography (CR) and indirect digital radiography (IDR) image receptors have been calculated, and compared with those for screen-film systems. Practical assessments of the relative sensitivities of a CR detector made using the detector dose indicator (DDI), pixel value and signal-to-noise ratio showed similar variations with tube potential. The DDI has been used to determine the correct kV compensation curve required to calibrate the AECs for the loss in detector sensitivity with tube potential. AECs are set up relative to a predetermined air kerma incident on the detector at 80 kV for CR and IDR systems using this curve and the method used is described. Factors influencing the calibration of AECs for digital radiography including techniques, types of phantom and contributions from scatter are reviewed, and practical methods recommended for use.

  18. The In-Flight Calibration of the GOCE Gradiometer

    NASA Astrophysics Data System (ADS)

    Cesare, Stefano; Catastini, Giuseppe; Floberghagen, Rune; Lamarre, Daniel

    2010-12-01

    Launched on March 17th 2009 from the Plesetsk Cosmodrome, GOCE (Gravity field and Ocean Circulation Explorer) is the first satellite among ESA's "Earth Explorer Core Missions". Flying in a sun-synchronous orbit with mean altitude of 259 km, GOCE exploits the gravity gradiometry technique for the determination of the Earth gravity field. The fundamental observables of this technique are the components of the gravity gradients tensor (GGT), measured by a set of six ultra-sensitive accelerometers constituting the "Gradiometer". The in-flight calibration of the Gradiometer plays a fundamental role in the final measurement accuracy of the GGT components. The Gradiometer calibration includes: i) the measurement and physical corrections of the first non-linear term in the transfer function of the accelerometers; ii) the measurement of the relative scale factors and alignments of the accelerometers for their utilization in the off-line data processing. The techniques utilized for the in-flight calibration of the Gradiometer are presented in this paper, together with the calibration results and their impact on the gradiometric performance.

  19. Real-Time Attitude Independent Three Axis Magnetometer Calibration

    NASA Technical Reports Server (NTRS)

    Crassidis, John L.; Lai, Kok-Lam; Harman, Richard R.

    2003-01-01

    In this paper new real-time approaches for three-axis magnetometer sensor calibration are derived. These approaches rely on a conversion of the magnetometer-body and geomagnetic-reference vectors into an attitude independent observation by using scalar checking. The goal of the full calibration problem involves the determination of the magnetometer bias vector, scale factors and non-orthogonality corrections. Although the actual solution to this full calibration problem involves the minimization of a quartic loss function, the problem can be converted into a quadratic loss function by a centering approximation. This leads to a simple batch linear least squares solution. In this paper we develop alternative real-time algorithms based on both the extended Kalman filter and Unscented filter. With these real-time algorithms, a full magnetometer calibration can now be performed on-orbit during typical spacecraft mission-mode operations. Simulation results indicate that both algorithms provide accurate integer resolution in real time, but the Unscented filter is more robust to large initial condition errors than the extended Kalman filter. The algorithms are also tested using actual data from the Transition Region and Coronal Explorer (TRACE).

  20. Calibration of a stochastic health evolution model using NHIS data

    NASA Astrophysics Data System (ADS)

    Gupta, Aparna; Li, Zhisheng

    2011-10-01

    This paper presents and calibrates an individual's stochastic health evolution model. In this health evolution model, the uncertainty of health incidents is described by a stochastic process with a finite number of possible outcomes. We construct a comprehensive health status index (HSI) to describe an individual's health status, as well as a health risk factor system (RFS) to classify individuals into different risk groups. Based on the maximum likelihood estimation (MLE) method and the method of nonlinear least squares fitting, model calibration is formulated in terms of two mixed-integer nonlinear optimization problems. Using the National Health Interview Survey (NHIS) data, the model is calibrated for specific risk groups. Longitudinal data from the Health and Retirement Study (HRS) is used to validate the calibrated model, which displays good validation properties. The end goal of this paper is to provide a model and methodology, whose output can serve as a crucial component of decision support for strategic planning of health related financing and risk management.

  1. Numerical Analysis of a Radiant Heat Flux Calibration System

    NASA Technical Reports Server (NTRS)

    Jiang, Shanjuan; Horn, Thomas J.; Dhir, V. K.

    1998-01-01

    A radiant heat flux gage calibration system exists in the Flight Loads Laboratory at NASA's Dryden Flight Research Center. This calibration system must be well understood if the heat flux gages calibrated in it are to provide useful data during radiant heating ground tests or flight tests of high speed aerospace vehicles. A part of the calibration system characterization process is to develop a numerical model of the flat plate heater element and heat flux gage, which will help identify errors due to convection, heater element erosion, and other factors. A 2-dimensional mathematical model of the gage-plate system has been developed to simulate the combined problem involving convection, radiation and mass loss by chemical reaction. A fourth order finite difference scheme is used to solve the steady state governing equations and determine the temperature distribution in the gage and plate, incident heat flux on the gage face, and flat plate erosion. Initial gage heat flux predictions from the model are found to be within 17% of experimental results.

  2. Linear positioning laser calibration setup of CNC machine tools

    NASA Astrophysics Data System (ADS)

    Sui, Xiulin; Yang, Congjing

    2002-10-01

    The linear positioning laser calibration setup of CNC machine tools is capable of executing machine tool laser calibraiotn and backlash compensation. Using this setup, hole locations on CNC machien tools will be correct and machien tool geometry will be evaluated and adjusted. Machien tool laser calibration and backlash compensation is a simple and straightforward process. First the setup is to 'find' the stroke limits of the axis. Then the laser head is then brought into correct alignment. Second is to move the machine axis to the other extreme, the laser head is now aligned, using rotation and elevation adjustments. Finally the machine is moved to the start position and final alignment is verified. The stroke of the machine, and the machine compensation interval dictate the amount of data required for each axis. These factors determine the amount of time required for a through compensation of the linear positioning accuracy. The Laser Calibrator System monitors the material temperature and the air density; this takes into consideration machine thermal growth and laser beam frequency. This linear positioning laser calibration setup can be used on CNC machine tools, CNC lathes, horizontal centers and vertical machining centers.

  3. Simplified calibration for broadband solar ultraviolet radiation measurements.

    PubMed

    Oppenrieder, A; Hoeppe, P; Koepke, P; Reuder, J; Schween, J; Schreder, J

    2003-12-01

    Aspects of different calibration procedures for erythemally weighing broadband radiometers are presented in this study. These instruments are common in projects dealing with ultraviolet radiation effects on humans. Many erythemally weighing broadband radiometers are still operated using a single calibration factor (cf) that is provided with the instrument. The individual characteristics of every instrument are strongly dependent on the total ozone amount and the solar elevation. Therefore, a calibration procedure also has to take into account the ozone concentrations and the solar elevation to compensate for the effects of the individual characteristics and to provide comparable measurements. Given the variation of the ozone concentrations and the solar elevation, an individual cf has to be calculated for every measurement. Using a simplified version of the calibration procedure, which is presented in this study, can lessen this effort. Taking into account the relevant meteorological conditions for a measuring site, a single cf is calculated to compensate the individual characteristics of the instruments and therefore deliver comparable measurements with less effort. PMID:14743870

  4. Radiometric Cross-Calibration of the HJ-1B IRS in the Thermal Infrared Spectral Band

    NASA Astrophysics Data System (ADS)

    Sun, K.

    2012-12-01

    The natural calamities occur continually, environment pollution and destruction in a severe position on the earth presently, which restricts societal and economic development. The satellite remote sensing technology has an important effect on improving surveillance ability of environment pollution and natural calamities. The radiometric calibration is precondition of quantitative remote sensing; which accuracy decides quality of the retrieval parameters. Since the China Environment Satellite (HJ-1A/B) has been launched successfully on September 6th, 2008, it has made an important role in the economic development of China. The satellite has four infrared bands; and one of it is thermal infrared. With application fields of quantitative remote sensing in china, finding appropriate calibration method becomes more and more important. Many kinds of independent methods can be used to do the absolute radiometric calibration. In this paper, according to the characteristic of thermal infrared channel of HJ-1B thermal infrared multi-spectral camera, the thermal infrared spectral band of HJ-1B IRS was calibrated using cross-calibration methods based on MODIS data. Firstly, the corresponding bands of the two sensors were obtained. Secondly, the MONDTRAN was run to analyze the influences of different spectral response, satellite view zenith angle, atmosphere condition and temperature on the match factor. In the end, their band match factor was calculated in different temperature, considering the dissimilar band response of the match bands. Seven images of Lake Qinghai in different time were chosen as the calibration data. On the basis of radiance of MODIS and match factor, the IRS radiance was calculated. And then the calibration coefficients were obtained by linearly regressing the radiance and the DN value. We compared the result of this cross-calibration with that of the onboard blackbody calibration, which consistency was good.The maximum difference of brightness temperature between HJ-1B IRS band4 and MODIS band 31 is less than 1 K. Therefore cross-calibration is a rapid and financial way to get calibration coefficients of HJ-1B, however, the matched factor calculation method need further research in order to further improve cross-calibration precision.

  5. GRAIN SIZING AND CALIBRATING OF DISTORTION BY IMAGE PROCESSING WITH INCLINED PHOTOGRAPH

    NASA Astrophysics Data System (ADS)

    Yasuda, Shingo; Ohashi, Keisuke; Ihara, Kazuki

    River bed material is normally heterogeneous, and the grain size distribution shows some features of each rivers. The information of distribution is, therefore, important factor in river engineering, and several traditional methods is practically used. Image processing method with digital photograph is modern analysis by using computer and replaced traditional analog photograph method. In image processing, however, optical distortion brings measurement error. We present a calibration of the distortion with optical theorem. In laboratory experiment with balls supposed river bed gravel, the theoretical calibration is considered to be appropriate. In field experiment, actual coefficient to calibrate distortion is estimated. In consequence of the investigation, it makes image processing method more accurate.

  6. Calibration and application of TRMM precipitation data in Irrawaddy River Basin

    NASA Astrophysics Data System (ADS)

    Qu, W.; Lu, J. X.; Zhang, T. T.; Tan, Y. N.; Song, W. L.; Pang, Z. G.

    2015-08-01

    The Tropical Rainfall Measuring Mission (TRMM) satellite rainfall data were assessed and calibrated using limited ground meteorological and hydrological data in Irrawaddy River basin, a watershed with complex terrain conditions but lack of data. A correction factor was determined to adjust TRMM data, taking basin water balance and terrain slopes into consideration. A distributed hydrological model SWAT was established and used to simulate the basin rainfall-runoff processes from 2001 to 2011, driven by the calibrated TRMM rainfall data series. Results show that, in a data scarce basin like Irrawaddy River basin, such a water balanced based TRMM data calibration method is suitable and reliable.

  7. Statistical perspectives of self-calibration

    NASA Astrophysics Data System (ADS)

    Raugh, Michael R.; Minor, James M.

    1996-05-01

    Positional self-calibration refers to the use of an imperfectly calibrated measurement gauge in an imperfectly calibrated measuring or manufacturing machine to simultaneously deduce improved positional accuracy in the calibrations of the gauge and the machine. The self- calibration function corrects the distortions in the image produced by a high-quality machine as it processes an object in its measurement field. The original derivation by Raugh (1984, 1985) focused on abstract mathematical/geometrical foundations of self-calibration. A later paper by Raugh (1991) dealt with the problem more concretely by showing how a patterned measurement gauge with suitable symmetry properties combined with near-linear comparisons could be used for self-calibration. This poster recasts self-calibration as a statistical problem. Hence, determination of the self-calibration function becomes a problem in statistical estimation, and specification of an optimal set of gauge positions and orientations for self- calibration becomes a problem in statistical design of experiment. This representation enables one to take advantage of established statistical methods for separating signal from extraneous effects and noise using stable and efficient techniques. An example of noise is measurement error. Extraneous effects include imperfections in the gauge and its positioning in the measurement field. The concepts are illustrated by a simple example.

  8. An SLF magnetic antenna calibration system

    NASA Astrophysics Data System (ADS)

    Shimin, Feng; Suihua, Zhou; Zhiyi, Chen; Hongxin, Zhang

    2014-05-01

    Calibrating the super low frequency (SLF) magnetic antenna in magnetic free space or an outdoor environment is difficult and complicated due to the large size calibration instruments and lots of measurement times. Aiming to calibrate the SLF magnetic antenna simply and efficiently, a calibration system comprised of a multi-frequency source, an AC constant-current source and a solenoid is proposed according to the characteristic of an SLF magnetic antenna. The static magnetic transfer coefficient of the designed solenoid is calibrated. The measurement of the frequency response characteristics suggests the transfer coefficient remains unchanged in the range of the SLF band and is unaffected by the magnetic antenna internally installed. The CORDIC algorithm implemented in an FPGA is realized to generate a linear evenly-spaced multi-frequency signal with equal energy at each frequency. An AC constant weak current source circuit is designed in order to avoid the impact on the magnetic induction intensity of a calibration system affected by impedance variation when frequency changing, linearity and the precision of the source are measured. The frequency characteristic of a magnetic antenna calibrated by the proposed calibration system agrees with the theoretical result and the standard Glass ring calibration result. The calibration precision satisfies the experimental requirement.

  9. Comparison of calibration results for an extrapolation chamber obtained with different 90Sr+90Y secondary standard sources.

    PubMed

    Antonio, Patrícia L; Carvalho, Valdir S; Caldas, Linda V E

    2012-02-01

    Two secondary standard systems of beta radiation were used to calibrate a PTW extrapolation chamber Model 23391. Three (90)Sr+(90)Y sources of different activities were used in this calibration procedure. Medium-term stability of the response of the chamber was also studied. The calibration was performed with and without field-flattening filters. The relative standard deviation of the obtained calibration factors was 8.3% for the aluminum collecting electrode and 4.1% for the graphite collecting electrode. PMID:22055844

  10. Feedstock Quality Factor Calibration and Data Model Development

    SciTech Connect

    Richard D. Boardman; Tyler L. Westover; Garold L. Gresham

    2010-05-01

    The goal of the feedstock assembly operation is to deliver uniform, quality-assured feedstock materials that will enhance downstream system performance by avoiding problems in the conversion equipment. In order to achieve this goal, there is a need for rapid screening tools and methodologies for assessing the thermochemical quality characteristics of biomass feedstock through the assembly process. Laser-induced breakdown spectroscopy (LIBS) has been identified as potential technique that could allow rapid elemental analyses of the inorganic content of biomass feedstocks; and consequently, would complement the carbohydrate data provided by near-infrared spectrometry (NIRS). These constituents, including Si, K, Ca, Na, S, P, Cl, Mg, Fe and Al, create a number of downstream problems in thermochemical processes. In particular, they reduce the energy content of the feedstock, influence reaction pathways, contribute to fouling and corrosion within systems, poison catalysts, and impact waste streams.

  11. Long-term stability of morphine hydrochloride in 0.9% NaCl infusion polyolefin bags after freeze-thaw treatment and in polypropylene syringes at 5 degrees C + 3 degrees C.

    PubMed

    Hecq, J-D; Godet, M; Gillet, P; Jamart, J; Galanti, L

    2014-01-01

    The aim of this study was to investigate the long-term stability of morphine hydrochloride in 0.9% NaCI infusion polyolefin bags and polypropylene syringes after storage at 5 degrees C + 3 degrees C and to evaluate the influence of initial freezing and microwave thawing on this stability. Ten polyolefin bags and five polypropylene syringes containing 100 mL of 1 mg/mL of morphine hydrochloride solution in 0.9% NaCI were prepared under aseptic conditions. Five polyolefin bags were frozen at -20 degrees C for 90 days before storage. Immediately after the preparation and after thawing, 2 mL of each bag were withdrawn for the initial concentration measurements. All polyolefin bags and polypropylene syringes were then refrigerated at 5 degrees C + 3 degrees C for 58 days during which the morphine concentrations were measured periodically by high-performance liquid chromatography using a reversed-phase column, naloxone as internal standard, a mobile phase consisting of 5% acetonitrile and 95% of KH2PO4 buffer (pH 3.50), and detection with diode array detector at 254 nm. Visual and microscopic observations and spectrophotometric and pH measurements were also performed. Solutions were considered stable if the concentration remained superior to 90% of the initial concentration. The degradation products peaks were not quantitatively significant and were resolved from the native drug. Polyolefin bag and polypropylene syringe solutions were stable when stored at 5 degrees C + 3 degrees C during these 58 days. No color change or precipitation in the solutions was observed. The physical stability was confirmed by visual, microscopic, and spectrophotometric inspection. There was no significant change in pH during storage. Freezing and microwave thawing didn't influence the infusion stability. Morphine hydrochloride infusions may be prepared in advance by centralized intravenous additive service, frozen in polyolefin bags, and microwave thawed before storage under refrigeration until 58 days either in polyolefin bags or polypropylene syringes. Such treatment could improve safety and management. PMID:24881344

  12. NASA metrology and calibration, 1993

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Th sixteenth annual workshop of NASA's Metrology and Calibration Working Group was held April 20-22, 1993. The goals of the Working Group are to provide Agencywide standardization of individual metrology programs, where appropriate; to promote cooperation and exchange of information within NASA, with other Government agencies, and with industry; to serve as the primary Agency interface with the National Institute of Standards and Technology; and to encourage formal quality control techniques such as Measurement Assurance Programs. These proceedings contain unedited reports and presentations from the workshop and are provided for information only.

  13. SMAP RADAR Calibration and Validation

    NASA Astrophysics Data System (ADS)

    West, R. D.; Jaruwatanadilok, S.; Chaubel, J.

    2014-12-01

    The Soil Moisture Active Passive (SMAP) mission is planned to launch on Jan 8, 2015. The mission employs L-band radar and radiometer measurements to estimate soil moisture with 4% volumetric accuracy at a resolution of 10 km, and freeze-thaw state at a resolution of 1-3 km. Immediately following launch, there will be a 3 month instrument checkout period, followed by 6 months of level 1 (L1) calibration and validation. In this presentation, we will discuss the plans and preparations for the calibration and validation of L1 radar data from SMAP. At the start of the L1 cal/val period, we will validate the operation of the instrument and of the ground processing using tools that look at readily identifiable surface features such as coast lines and corner reflectors. Geometric biases will be fit and removed. Radiometric cross-calibration with PALSAR and Aquarius will also be performed using target regions in the Amazon rain forest selected for their stability and uniformity. As the L1 cal/val period progresses, the performance of the automated short and long term calibration modules in ground processing will be tracked and verified using data from stable reference targets such as the wind corrected ocean and selected areas of rain forest that have shown good temporal stability. The performance of the radio frequency interference (RFI) removal algorithm will be validated by processing data with the algorithm turned on and off, and using different parameter settings. Additional information on the extent of RFI will be obtained from a special RFI survey conducted early in the L1 cal/val period. Radar transmissions are turned off during the RFI survey, and receive only data are collected over a variety of operating frequencies. The model based Faraday rotation corrections will also be checked during the L1 cal/val by comparing the model Faraday rotation with the measured Faraday rotation obtained by the SMAP Radiometer. This work is supported by the SMAP project at the Jet Propulsion Laboratory, California Institute of Technology.

  14. Absolute calibration of optical tweezers

    SciTech Connect

    Viana, N.B.; Mazolli, A.; Maia Neto, P.A.; Nussenzveig, H.M.; Rocha, M.S.; Mesquita, O.N.

    2006-03-27

    As a step toward absolute calibration of optical tweezers, a first-principles theory of trapping forces with no adjustable parameters, corrected for spherical aberration, is experimentally tested. Employing two very different setups, we find generally very good agreement for the transverse trap stiffness as a function of microsphere radius for a broad range of radii, including the values employed in practice, and at different sample chamber depths. The domain of validity of the WKB ('geometrical optics') approximation to the theory is verified. Theoretical predictions for the trapping threshold, peak position, depth variation, multiple equilibria, and 'jump' effects are also confirmed.

  15. Absolute calibration of optical tweezers

    NASA Astrophysics Data System (ADS)

    Viana, N. B.; Mazolli, A.; Maia Neto, P. A.; Nussenzveig, H. M.; Rocha, M. S.; Mesquita, O. N.

    2006-03-01

    As a step toward absolute calibration of optical tweezers, a first-principles theory of trapping forces with no adjustable parameters, corrected for spherical aberration, is experimentally tested. Employing two very different setups, we find generally very good agreement for the transverse trap stiffness as a function of microsphere radius for a broad range of radii, including the values employed in practice, and at different sample chamber depths. The domain of validity of the WKB ("geometrical optics") approximation to the theory is verified. Theoretical predictions for the trapping threshold, peak position, depth variation, multiple equilibria, and "jump" effects are also confirmed.

  16. Calibration Monitor for Dark Energy Experiments

    SciTech Connect

    Kaiser, M. E.

    2009-11-23

    The goal of this program was to design, build, test, and characterize a flight qualified calibration source and monitor for a Dark Energy related experiment: ACCESS - 'Absolute Color Calibration Experiment for Standard Stars'. This calibration source, the On-board Calibration Monitor (OCM), is a key component of our ACCESS spectrophotometric calibration program. The OCM will be flown as part of the ACCESS sub-orbital rocket payload in addition to monitoring instrument sensitivity on the ground. The objective of the OCM is to minimize systematic errors associated with any potential changes in the ACCESS instrument sensitivity. Importantly, the OCM will be used to monitor instrument sensitivity immediately after astronomical observations while the instrument payload is parachuting to the ground. Through monitoring, we can detect, track, characterize, and thus correct for any changes in instrument senstivity over the proposed 5-year duration of the assembled and calibrated instrument.

  17. Radio Interferometric Calibration Using The SAGE Algorithm

    E-print Network

    Sarod Yatawatta; Saleem Zaroubi; Ger de Bruyn; Leon Koopmans; Jan Noordam

    2008-10-31

    Radio Interferometry is an essential method for astronomical observations. Self-calibration techniques have increased the quality of the radio astronomical observations (and hence the science) by orders of magnitude. Recently, there is a drive towards sensor arrays built using inexpensive hardware and distributed over a wide area acting as radio interferometers. Calibration of such arrays poses new problems in terms of computational cost as well as in performance of existing calibration algorithms. We consider the application of the Space Alternating Generalized Expectation Maximization (SAGE) \\cite{Fess94} algorithm for calibration of radio interferometric arrays. Application to real data shows that this is an improvement over existing calibration algorithms that are based on direct, deterministic non linear optimization. As presented in this paper, we can improve the computational cost as well as the quality of the calibration using this algorithm.

  18. Method for calibrating the fisheye distortion center.

    PubMed

    Huang, Fuyu; Wang, Yongzhong; Shen, Xueju; Lin, Chao; Chen, Yudan

    2012-12-01

    A simple method is proposed to calibrate the fisheye distortion center, which synthesizes the algorithms of the ellipse fitting and gaussian surface fitting. Through analyzing the imaging projection of the equidistant fisheye lens, the calibration principle is introduced in detail. From the experimental results, we find that ellipse fitting error and the relative error of gaussian surface fitting are less than 0.06 pixels and 1.5%, respectively, and the proposed method has a higher calibration precision and stability compared with the methods in the inferences. Besides, the proposed method does not rely on any particular distortion model and other fisheye parameters, and only the image information of the calibration board is utilized, which reduces the calibration complexity and is suitable for the center calibration of any equidistant fisheye camera. PMID:23207386

  19. Automated Heat-Flux-Calibration Facility

    NASA Technical Reports Server (NTRS)

    Liebert, Curt H.; Weikle, Donald H.

    1989-01-01

    Computer control speeds operation of equipment and processing of measurements. New heat-flux-calibration facility developed at Lewis Research Center. Used for fast-transient heat-transfer testing, durability testing, and calibration of heat-flux gauges. Calibrations performed at constant or transient heat fluxes ranging from 1 to 6 MW/m2 and at temperatures ranging from 80 K to melting temperatures of most materials. Facility developed because there is need to build and calibrate very-small heat-flux gauges for Space Shuttle main engine (SSME).Includes lamp head attached to side of service module, an argon-gas-recirculation module, reflector, heat exchanger, and high-speed positioning system. This type of automated heat-flux calibration facility installed in industrial plants for onsite calibration of heat-flux gauges measuring fluxes of heat in advanced gas-turbine and rocket engines.

  20. Assessing Calibration of Prognostic Risk Scores

    PubMed Central

    Crowson, Cynthia S.; Atkinson, Elizabeth J.; Therneau, Terry M.

    2014-01-01

    Current methods used to assess calibration are limited, particularly in the assessment of prognostic models. Methods for testing and visualizing calibration (e.g., the Hosmer-Lemeshow test and calibration slope) have been well thought out in the binary regression setting. However, extension of these methods to Cox models are less well-known, and could be improved. We describe a model-based framework for assessment of calibration in the binary setting that provides natural extensions to the survival data setting. We show that Poisson regression models can be used to easily assess calibration in prognostic models. In addition, we show that a calibration test suggested for use in survival data has poor performance. Finally, we apply these methods to the problem of external validation of a risk score developed for the general population when assessed in a special patient population (i.e., patients with particular comorbidities, such as rheumatoid arthritis). PMID:23907781

  1. Biogeographic calibrations for the molecular clock.

    PubMed

    Ho, Simon Y W; Tong, K Jun; Foster, Charles S P; Ritchie, Andrew M; Lo, Nathan; Crisp, Michael D

    2015-09-01

    Molecular estimates of evolutionary timescales have an important role in a range of biological studies. Such estimates can be made using methods based on molecular clocks, including models that are able to account for rate variation across lineages. All clock models share a dependence on calibrations, which enable estimates to be given in absolute time units. There are many available methods for incorporating fossil calibrations, but geological and climatic data can also provide useful calibrations for molecular clocks. However, a number of strong assumptions need to be made when using these biogeographic calibrations, leading to wide variation in their reliability and precision. In this review, we describe the nature of biogeographic calibrations and the assumptions that they involve. We present an overview of the different geological and climatic events that can provide informative calibrations, and explain how such temporal information can be incorporated into dating analyses. PMID:26333662

  2. Calibration of the IMB Detector

    SciTech Connect

    Becker-Szendy, R.; Bionta, R.M.; Bratton, C.B.; Casper, D.; Claus, R.; Cortez, B.; Dye, S.T.; Errede, S.; Foster, G.W.; Gajewski, W.; Ganezer, K.; Goldhaber, M.; Haines, T.J.; Halverson, P.G.; Hazen, E.; Jones, T.W.; Kielczewska, D.; Kropp, W.R.; Learned, J.G.; Losecco, J.M.; Matsuno, S.; /UC, Irvine /Michigan U. /Brookhaven /Boston U. /Hawaii U. /University Coll. London /Warsaw U. /Cleveland State U. /Notre Dame U. /Louisiana State U. /Maryland U. /AT-T Bell Labs, Holmdel /Illinois U., Urbana /Fermilab /LLNL, Livermore /New Mexico U. /SLAC /Adelaide U. /CERN /Cal State, Dominguez Hills

    2012-04-03

    The IMB detector (named after its founding institutions: University of California, Irvine, the University of Michigan and Brookhaven National Laboratory) collected data on a wide range of phenomena for over eight years. It was the first and the largest of the ring imaging water Cherenkov detectors. The detector consisted of 8000 metric tons of ultra-pure water instrumented with 2048 photomultiplier tubes (PMTs). The PMTs were placed on the roof, floor, and walls of the detector in a lattice of approximately 1 m spacing. It made measurements of contained events that ranged in energy from 15 MeV up to 1.5 GeV. This paper describes the calibration of the IMB detector. This procedure was accurate and stable over a wide range of physical variables. It was used with little change throughout the entire eight-year lifetime of the experiment. The IMB calibration is a model for future large-scale detectors that employ the water Cherenkov technique.

  3. Energy Calibration of PVT Detectors

    NASA Astrophysics Data System (ADS)

    Ely, James; Siciliano, Edward; Shepard, Chester

    2004-05-01

    Due to relatively low cost and durability, large-area polyvinyl-toluene (PVT) scintillators are widely used for gamma-ray detection in radiation portal monitors (RPMs). Gamma-ray interactions in PVT are dominated by Compton scattering - a partial-energy deposition mechanism. This mechanism can provide total count rates sufficient for detecting radiation, but because there are no discernable total-energy photopeaks in the PVT response functions, energy calibration is very challenging. Energy calibration of PVT-based systems is important for several reasons. First, manufacturers often quote energy ranges for the gamma detectors, but these ranges are difficult to verify. Secondly, the Compton edges and continuum can provide limited energy information by selecting a few broad energy windows - a technique that may be helpful to distinguish naturally occurring radioactive materials from other sources. In this presentation, methods for making experimental determinations of low-energy thresholds and energy windows in PVT detectors are described. Example cases will be shown for detectors from two manufacturers. Because of the relative simplicity of these methods, they may be useful for estimating the discriminator threshold settings and energy windows in field applications.

  4. Oxygen-Mass-Flow Calibration Cell

    NASA Technical Reports Server (NTRS)

    Martin, Robert E.

    1996-01-01

    Proposed calibration standard for mass flow rate of oxygen based on conduction of oxygen ions through solid electrolyte membrane made of zirconia and heated to temperature of 1,000 degrees C. Flow of oxygen ions proportional to applied electric current. Unaffected by variations in temperature and pressure, and requires no measurement of volume. Calibration cell based on concept used to calibrate variety of medical and scientific instruments required to operate with precise rates of flow of oxygen.

  5. 1987 calibration of the TFTR neutron spectrometers

    SciTech Connect

    Barnes, C.W.; Strachan, J.D.; Princeton Univ., NJ . Plasma Physics Lab.)

    1989-12-01

    The {sup 3}He neutron spectrometer used for measuring ion temperatures and the NE213 proton recoil spectrometer used for triton burnup measurements were absolutely calibrated with DT and DD neutron generators placed inside the TFTR vacuum vessel. The details of the detector response and calibration are presented. Comparisons are made to the neutron source strengths measured from other calibrated systems. 23 refs., 19 figs., 6 tabs.

  6. A BPM calibration procedure using TBT data

    SciTech Connect

    Yang, M.J.; Crisp, J.; Prieto, P.; /Fermilab

    2007-06-01

    Accurate BPM calibration is crucial for lattice analysis. It is also reassuring when the calibration can be independently verified. This paper outlines a procedure that can extract BPM calibration information from TBT orbit data. The procedure is developed as an extension to the Turn-By-Turn lattice analysis [1]. Its application to data from both Recycler Ring and Main Injector (MI) at Fermilab have produced very encouraging results. Some specifics in hardware design will be mentioned to contrast that of analysis results.

  7. Calibration of x-ray projections in 3D reconstruction

    NASA Astrophysics Data System (ADS)

    Wang, Ping; Mou, Xuanqin; Qin, Zhongyuan; Cai, Yuanlong

    2001-09-01

    In cone-beam 3D CT, 2D X-ray projections determine the reconstruction quality directly. However, the generation of an X-ray projection is a complex process that includes the emission, the conversion and the transfer of X-ray latent information, so the pixel value of a projection has no exact meaning generally. In this paper, we suggest a way by experiments to model the whole imaging system based on 'equivalent single energy' which is used to analyze polychromatic X-ray. We define each tissue's SCF(single calibration factor) of human and get GCF (gross calibration factor) by summing up every weighted SCF, then we can use GCF to calibrate and linearize X-ray projections. After such processing, X-ray projection will have explicit meaning, i.e. its pixel value can denote the equivalent material thickness linearly, which will be advantageous to the algorithm research of 3D reconstruction and other quantitative analyses of human's physiological parameters.

  8. SDSS-IV/MaNGA: Spectrophotometric Calibration Technique

    NASA Astrophysics Data System (ADS)

    Yan, Renbin; Tremonti, Christy; Bershady, Matthew A.; Law, David R.; Schlegel, David J.; Bundy, Kevin; Drory, Niv; MacDonald, Nicholas; Bizyaev, Dmitry; Blanc, Guillermo A.; Blanton, Michael R.; Cherinka, Brian; Eigenbrot, Arthur; Gunn, James E.; Harding, Paul; Hogg, David W.; Sánchez-Gallego, José R.; Sánchez, Sebastian F.; Wake, David A.; Weijmans, Anne-Marie; Xiao, Ting; Zhang, Kai

    2016-01-01

    Mapping Nearby Galaxies at Apache Point Observatory (MaNGA), one of three core programs in the Sloan Digital Sky Survey-IV, is an integral-field spectroscopic survey of roughly 10,000 nearby galaxies. It employs dithered observations using 17 hexagonal bundles of 2? fibers to obtain resolved spectroscopy over a wide wavelength range of 3600-10300 Å. To map the internal variations within each galaxy, we need to perform accurate spectral surface photometry, which is to calibrate the specific intensity at every spatial location sampled by each individual aperture element of the integral field unit. The calibration must correct only for the flux loss due to atmospheric throughput and the instrument response, but not for losses due to the finite geometry of the fiber aperture. This requires the use of standard star measurements to strictly separate these two flux loss factors (throughput versus geometry), a difficult challenge with standard single-fiber spectroscopy techniques due to various practical limitations. Therefore, we developed a technique for spectral surface photometry using multiple small fiber-bundles targeting standard stars simultaneously with galaxy observations. We discuss the principles of our approach and how they compare to previous efforts, and we demonstrate the precision and accuracy achieved. MaNGA's relative calibration between the wavelengths of H? and H? has an rms of 1.7%, while that between [N ii] ?6583 and [O ii] ?3727 has an rms of 4.7%. Using extinction-corrected star formation rates and gas-phase metallicities as an illustration, this level of precision guarantees that flux calibration errors will be sub-dominant when estimating these quantities. The absolute calibration is better than 5% for more than 89% of MaNGA's wavelength range.

  9. Pressure Transducer Remote Calibration/Health Check

    NASA Technical Reports Server (NTRS)

    Deyoe, Richard; Voska, Ned (Technical Monitor)

    2002-01-01

    This presentation reports on efforts to develop an in-situ pressure transducer calibration system for extension of calibration lifecycle and transducer health determination. This system aims to: (1) provide a long term solution to determining the calibration of pressure transducers for gas applications, (2) provide a method of isolating problems in remote measurements, and (3) reduce costs and resources by extending the length of time a transducer may be left in a system without a repeat laboratory calibration. Topic covers include: design requirements, design assumptions and design approach.

  10. SMOS-MIRAS Calibration and Performance

    NASA Astrophysics Data System (ADS)

    Corbella, Ignasi; Torres, Francesc; Gonzalez-Gambau, Veronica; Duffo, Nuria; Pablos, Miriam; Duran, Israel; Closa, Josep; Martin-Neira, Manuel

    2010-12-01

    An intense activity has been carried out during the in- orbit commissioning phase of the SMOS (Soil Moisture and Ocean Salinity) mission. Concerning the payload MIRAS (Microwave Imaging Radiometer with Aperture Synthesis) it has been fully characterized using specific orbits dedicated to check all instrument modes. The procedures, already defined during the on-ground characterization, have been repeated so as to obtain realistic temperature characterization and updated internal calibration parameters. External calibration maneuvers have been tested for the first time and have provided absolute instrument calibration, as well as corrections to improve the internal calibration data.

  11. 14 CFR 33.85 - Calibration tests.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Block Tests; Turbine Aircraft Engines § 33.85 Calibration tests. (a) Each engine must be...

  12. 14 CFR 33.45 - Calibration tests.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.45 Calibration tests. (a) Each engine must be...

  13. FY2008 Calibration Systems Final Report

    SciTech Connect

    Cannon, Bret D.; Myers, Tanya L.; Broocks, Bryan T.

    2009-01-01

    The Calibrations project has been exploring alternative technologies for calibration of passive sensors in the infrared (IR) spectral region. In particular, we have investigated using quantum cascade lasers (QCLs) because these devices offer several advantages over conventional blackbodies such as reductions in size and weight while providing a spectral source in the IR with high output power. These devices can provide a rapid, multi-level radiance scheme to fit any nonlinear behavior as well as a spectral calibration that includes the fore-optics, which is currently not available for on-board calibration systems.

  14. Calibration of multi-camera photogrammetric systems

    NASA Astrophysics Data System (ADS)

    Detchev, I.; Mazaheri, M.; Rondeel, S.; Habib, A.

    2014-11-01

    Due to the low-cost and off-the-shelf availability of consumer grade cameras, multi-camera photogrammetric systems have become a popular means for 3D reconstruction. These systems can be used in a variety of applications such as infrastructure monitoring, cultural heritage documentation, biomedicine, mobile mapping, as-built architectural surveys, etc. In order to ensure that the required precision is met, a system calibration must be performed prior to the data collection campaign. This system calibration should be performed as efficiently as possible, because it may need to be completed many times. Multi-camera system calibration involves the estimation of the interior orientation parameters of each involved camera and the estimation of the relative orientation parameters among the cameras. This paper first reviews a method for multi-camera system calibration with built-in relative orientation constraints. A system stability analysis algorithm is then presented which can be used to assess different system calibration outcomes. The paper explores the required calibration configuration for a specific system in two situations: major calibration (when both the interior orientation parameters and relative orientation parameters are estimated), and minor calibration (when the interior orientation parameters are known a-priori and only the relative orientation parameters are estimated). In both situations, system calibration results are compared using the system stability analysis methodology.

  15. Calibration of ACS Prism Slitless Spectroscopy Modes

    E-print Network

    S. S. Larsen; M. Kuemmel; J. R. Walsh

    2005-12-05

    The Advanced Camera for Surveys is equipped with three prisms in the Solar Blind (SBC) and High Resolution (HRC) Channels, which together cover the 1150 - 3500 A range, albeit at highly non-uniform spectral resolution. We present new wavelength- and flux calibrations of the SBC (PR110L and PR130L) and HRC (PR200L) prisms, based on calibration observations obtained in Cycle 13. The calibration products are available to users via the ST-ECF/aXe web pages, and can be used directly with the aXe package. We discuss our calibration strategy and some caveats specific to slitless prism spectroscopy.

  16. Calibration of water-velocity meters

    USGS Publications Warehouse

    Kaehrle, William R.; Bowie, James E.

    1988-01-01

    The U.S. Geological Survey, Department of the Interior, as part of its responsibility to appraise the quantity of water resources in the United States, maintains facilities for the calibration of water-velocity meters at the Gulf Coast Hydroscience Center's Hydraulic Laboratory Facility, NSTL, Mississippi. These meters are used in hydrologic studies by the Geological Survey, U.S. Army Corps of Engineers, U.S. Department of Energy, state agencies, universities, and others in the public and private sector. This paper describes calibration facilities, types of water-velocity meters calibrated, and calibration standards, methods and results.

  17. Calibration of the AXAF Observatory: Overview

    NASA Technical Reports Server (NTRS)

    Weisskopf, M. C.; ODell, S. L.

    1997-01-01

    The Advanced X-ray Astrophysics Facility (AXAF) will soon begin its exploration of the x-ray universe, providing unprecedented angular and spectral resolution. Also unprecedented is the ambitious goal of calibrating the AXAF observatory to an accuracy of a few percent. Toward this end, AXAF science and engineering teams undertook an extensive calibration program at component, subsystem, and system levels. This paper is an overview of the system-level calibration activities, conducted over the past year at the Marshall Space Flight Center (MSFC) X-Ray Calibration Facility (XRCF).

  18. Spectral calibration of programmable imaging spectrometer

    NASA Astrophysics Data System (ADS)

    Du, Guojun; Liao, Zhibo; Jiao, Wenchun; Zong, Xiaoying; He, Xuhua; Wang, Haichao

    2015-10-01

    Programmable imager spectrometer can provide flexible data by changing the spectrum section number, central wavelength, spectral width and spatial resolution in orbit. Spectral calibration of imaging spectrometer plays an important role for acquiring accurate spectrum, two spectral calibration types are in essence: wavelength calibration and Full-width-half-maximum (FWHM). Base on the character of programmable imager spectrometer, designed a set of spectral calibration system. Wavelength calibration realized by utilizing the Monochromatic light of high precision monochromator, during the test, changed output parameters of monochromator according to the spectral bandwidth of imager spectrometer. The FWHM is constructed by a set of variable narrow spectrum lines that is output by tunable laser. Gaussian fitting algorithm is used to determine center wavelength and the FWHM of the characteristic spectrum line, Spectral pixels are calibrated by quadratic polynomial, standard spectroscopic lamp is used to verify wavelength calibration result accuracy. The calibration result indicates that FWHM is better than 2nm, the wavelength uncertainty is less than 0.6nm, meet the calibration requirements of programmable imaging spectrometer.

  19. Sloan Digital Sky Survey Photometric Calibration Revisited

    SciTech Connect

    Marriner, John; /Fermilab

    2012-06-29

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  20. Development of an H(2)(15)O steady-state method combining a bolus and slow increasing injection with a multiprogramming syringe pump.

    PubMed

    Kobayashi, Masato; Kiyono, Yasushi; Maruyama, Rikiya; Mori, Tetsuya; Kawai, Keiichi; Okazawa, Hidehiko

    2011-02-01

    An (15)O-labeled water (H(2)(15)O) steady-state method for quantitative measurement of cerebral blood flow (CBF), which is less stressful to small animals with a few point blood sampling, was developed. After a simulation using a dose meter to achieve stable H(2)(15)O radioactivity in the blood with a multiprogramming syringe pump programmed for slowly increasing injection volume, 10 rats were studied with the injection method. Arterial blood was sampled every minute during 6-minute positron emission tomography (PET) scans. After the PET scan, N-isopropyl-p-[(125)I]-iodoamphetamine ((125)I-IMP) was injected into the same rat to measure CBF using the autoradiography method based on a microsphere model. Regions of interest were placed on the whole brain in H(2)(15)O-PET and (125)I-IMP-autoradiography images, and CBF values calculated from both methods were compared. Radioactivity in the dose meter achieved equilibrium ?1?minute after starting the H(2)(15)O injection. In rat studies, radioactivity in the blood and brain rapidly achieved equilibrium at 2?minutes after administration. The correlation of CBF values of H(2)(15)O PET (49.2±5.4?mL per 100?g per minute) and those of (125)I-IMP autoradiography (49.1±5.2?mL per 100?g per minute) was excellent (y=1.01x-0.37, r(2)=0.97). The H(2)(15)O steady-state method with a continuously increasing injection is useful for CBF measurement in small animal studies, especially when multiple scans are required in the same animal. PMID:20664614

  1. OGIP Calibration Memo CAL/GEN/94-002 The Calibration Database User's Guide

    E-print Network

    Nishikawa, Ken-Ichi

    -database in which calibration datasets are linked to software via Calibration Index Files (CIFs). CIFs contain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.2 How to Customize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4 COMMON PROBLEMS & FAQs 6 4.1 I don't understand anything

  2. Design and Calibration of a Cryogenic Blackbody Calibrator at Centimeter Wavelengths

    E-print Network

    A. Kogut; E. Wollack; D. J. Fixsen; M. Limon; P. Mirel; S. Levin; M. Seiffert; P. M. Lubin

    2004-02-24

    We describe the design and calibration of an external cryogenic blackbody calibrator used for the first two flights of the Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission (ARCADE) instrument. The calibrator consists of a microwave absorber weakly coupled to a superfluid liquid helium bath. Half-wave corrugations viewed 30 deg off axis reduce the return loss below -35 dB. Ruthenium oxide resistive thermometers embedded within the absorber monitor the temperature across the face of the calibrator. The thermal calibration transfers the calibration of a reference thermometer to the flight thermometers using the flight thermometer readout system. Data taken near the superfluid transition in 8 independent calibrations 4 years apart agree within 0.3 mK, providing an independent verification of the thermometer calibration at temperatures near that of the cosmic microwave background.

  3. A Summary of The 2000-2001 NASA Glenn Lear Jet AM0 Solar Cell Calibration Program

    NASA Technical Reports Server (NTRS)

    Scheiman, David; Brinker, David; Snyder, David; Baraona, Cosmo; Jenkins, Phillip; Rieke, William J.; Blankenship, Kurt S.; Tom, Ellen M.

    2002-01-01

    Calibration of solar cells for space is extremely important for satellite power system design. Accurate prediction of solar cell performance is critical to solar array sizing, often required to be within 1%. The NASA Glenn Research Center solar cell calibration airplane facility has been in operation since 1963 with 531 flights to date. The calibration includes real data to Air Mass (AM) 0.2 and uses the Langley plot method plus an ozone correction factor to extrapolate to AM0. Comparison of the AM0 calibration data indicates that there is good correlation with Balloon and Shuttle flown solar cells. This paper will present a history of the airplane calibration procedure, flying considerations, and a brief summary of the previous flying season with some measurement results. This past flying season had a record 35 flights. It will also discuss efforts to more clearly define the ozone correction factor.

  4. Radar Calibration Using a Student-Built Nanosatellite

    NASA Astrophysics Data System (ADS)

    Martin, L.; Fisher, N.; Jones, W.; Umeda, M.; Furumo, J.; Ah Heong, J.; Lim, T.; Shiroma, W.

    2011-09-01

    As a matter of national security, the US military must monitor and calibrate its 80+ C-band radar tracking stations on a consistent basis. These radar stations, which are distributed around the world, currently depend on two calibration satellites: RADCAL and DMSP F-15, launched in 1993 and 1999, respectively. Should either of these two satellites fail, the community of radar calibration users will no longer have a dependable means of calibration. Presented in this paper is the story behind a student-built satellite project, named Ho‘oponopono (“to make right” in the Hawaiian language), which is the first radar calibration satellite to take on a CubeSat form-factor. Led by a team of undergraduate and graduate students, this project has enabled its participants to reach their true potentials and thus act as a training ground for a class of highly competent, multi-tiered engineers. The management practices implemented throughout this project follow those used by today’s top defense contractors and engineering companies. Being involved in a project of this caliber, although time-consuming, provides the students with the experiences they need to make immediate and worthwhile contributions in today’s workforce. Juggling the multitude of commitments they have, however, makes it a challenge. Ho‘oponopono’s concept of operations calls for the collection and dissemination of ephemeris data, while simultaneously conducting transponder interrogations. After acquiring both sets of data, a radar station requesting calibration can then correlate the two and implement its calibration algorithms as needed. Ho‘oponopono and its mission were the basis for the University of Hawaii’s participation in the AFOSR University Nanosat-6 Program. After completing a rigorous two-year, six-level review process, we were awarded with the Most Improved and Third Place Awards at the January 2011 Flight Competition Review. Ho‘oponopono was also selected by NASA as a participant in its CubeSat Launch Initiative for an upcoming launch.

  5. Calibration of ionization chambers in air kerma length

    NASA Astrophysics Data System (ADS)

    Bochud, François O.; Grecescu, Mihail; Valley, Jean-François

    2001-09-01

    Pencil ionization chambers are employed for the direct determination of the computed tomography dose index (CTDI), which is used for patient dosimetry in CT examinations. The chambers are calibrated in air kerma length in a reference x-ray field. The precision of calibration is influenced by several factors which are investigated in the present work. It is shown that the best irradiation length is 50% of the chamber rated length. The reading must be corrected for a residual signal due to the irradiation of the sensitive chamber volume by scattered radiation. The origin of this radiation is identified mainly at the edges of the diaphragm limiting the useful field. The residual signal is determined by a linear fit of measurements performed at minimum of three diaphragm apertures. The optimum geometric conditions are also discussed.

  6. Method and Apparatus for Accurately Calibrating a Spectrometer

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert C. (Inventor); Simmons, Stephen M. (Inventor)

    2013-01-01

    A calibration assembly for a spectrometer is provided. The assembly includes a spectrometer having n detector elements, where each detector element is assigned a predetermined wavelength value. A first source emitting first radiation is used to calibrate the spectrometer. A device is placed in the path of the first radiation to split the first radiation into a first beam and a second beam. The assembly is configured so that one of the first and second beams travels a path-difference distance longer than the other of the first and second beams. An output signal is generated by the spectrometer when the first and second beams enter the spectrometer. The assembly includes a controller operable for processing the output signal and adapted to calculate correction factors for the respective predetermined wavelength values assigned to each detector element.

  7. Calibration: What Is It and Why It Matters? An Introduction to the Special Issue on Calibrating Calibration

    ERIC Educational Resources Information Center

    Alexander, Patricia A.

    2013-01-01

    The burgeoning literatures on students' metacognitive judgments, self-regulation, self-efficacy beliefs, strategic processing, and conceptual change have focused new attention on the nature and measurement of calibration. Calibration, the distance between perceived and demonstrated levels of understanding, capability, competence, or preparedness,…

  8. Calibration of a gamma calibration well with an energy-compensated Geiger-Mueller (G-M) tube.

    SciTech Connect

    George, G. L.; Seagraves, D. T.; Valdez, D. T.

    2001-01-01

    A working-standard Radcal model 1515 radiation monitor with the 1800cc ion chamber was used previously at Los Alamos National Laboratory (LANL) to calibrate and perform routine QA checks on the low-level gamma well, which produces exposure rates in the range of 0.2 mR/h to 10 mR/h. During long integration times (e.g. 24-48 hrs) with the 1800 cc ion chamber, which were required to obtain the necessary precision, changes in temperature and pressure and fluctuations in the zero offset introduced errors that were difficult to account for. An energy compensated G-M tube (SHP-270) was calibrated as a Working Standard to calibrate and perform QA checks on the low-level gamma well. Energy correction factors were determined since the SHP-270 does not have a linear energy response. Monte Carlo N-Particle (MCNP) code was used to determine the exposure rate in 50 keV energy bins as a function of source distance in the well. The results of these calculations were folded into the energy correction factors of the SHP-270 to determine the Corrected Exposure Rate as a function of source distance. To recalibrate the gamma well, the Corrected Exposure Rates were loaded into the source control algorithm, which was then verified to work correctly.

  9. Socio-demographic factors, health risks and harms associated with early initiation of injection among people who inject drugs in Tallinn, Estonia: evidence from cross-sectional surveys

    PubMed Central

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

    2012-01-01

    Aim To explore socio-demographic factors, health risks and harms associated with early initiation of injecting (before age 16) among injecting drug users (IDUs) in Tallinn, Estonia. Methods IDUs were recruited using respondent driven sampling methods for two cross-sectional interviewer-administered surveys (in 2007 and 2009). Bivariate and multivariate logistic regression analysis was used to identify factors associated with early initiation versus later initiation. Results A total of 672 current IDUs reported the age when they started to inject drugs; the mean was 18 years, and about a quarter of the sample (n=156) reported early initiation into injecting drugs. Factors significantly associated in multivariate analysis with early initiation were being female, having a lower educational level, being unemployed, shorter time between first drug use and injecting, high-risk injecting (sharing syringes and paraphernalia, injecting more than once a day), involvement in syringe exchange attendance and getting syringes from outreach workers, and two-fold higher risk of HIV seropositivity. Conclusions Our results document significant adverse health consequences (including higher risk behaviour and HIV seropositivity) associated with early initiation into drug injecting and emphasize the need for comprehensive prevention programs and early intervention efforts targeting youth at risk. Our findings suggest that interventions designed to delay the age of starting drug use, including injecting drug use, can contribute to reducing risk behaviour and HIV prevalence among IDUs. PMID:23036651

  10. A Cryogenic Infrared Calibration Target

    NASA Technical Reports Server (NTRS)

    Wollack, E. J.; Kinzer, R. E., Jr.; Rinehart, S. A.

    2014-01-01

    A compact cryogenic calibration target is presented that has a peak diffuse reflectance, R < or = 0.003, from 800 to 4800/cm (12 - 2 microns ). Upon expanding the spectral range under consideration to 400-10,000/ cm-1 (25 - 1 microns) the observed performance gracefully degrades to R < or = 0.02 at the band edges. In the implementation described, a high-thermal-conductivity metallic substrate is textured with a pyramidal tiling and subsequently coated with a thin lossy dielectric coating that enables high absorption and thermal uniformity across the target. The resulting target assembly is lightweight, has a low-geometric profile, and has survived repeated thermal cycling from room temperature to approx.4 K. Basic design considerations, governing equations, and test data for realizing the structure described are provided. The optical properties of selected absorptive materials-Acktar Fractal Black, Aeroglaze Z306, and Stycast 2850 FT epoxy loaded with stainless steel powder-are characterized and presented

  11. Whistler and FLR density calibration

    NASA Astrophysics Data System (ADS)

    Lichtenberger, János; Vellante, Massimo; Heilig, Balázs; Ferencz, Csaba; Regi, Mauro; Clilverd, Mark; Juhász, Lilla

    2014-05-01

    One of the major objective in PLASMON (http://plasmon.elte.hu) project is to provide plasma densities for data assimilative modeling of plasmasphere from two ground based measurements: whistlers and field line resonances (FLRs). The whistler inversion method used in this procedure includes various model, including wave propagation, magnetic field, field aligned density distribution and equatorial electron density models. The latter one is a special one used for multiple-path whistler groups. As one can obtain electron densities from whistler inversion and plasma mass densities from FLRs, the ion composition would be required to connect the to dataset (that are intended to use in the plasmasphere model), which is rarely known or available. Therefore we have developed a method for cross calibration of the data from two sources. It is based on physics based and experimental field aligned plasma density distribution models as well as on comparison with in situ wave and density (IMAGE and Van Allen Probes) measurements.

  12. Lens distortion calibration using homography

    NASA Astrophysics Data System (ADS)

    Xu, X. Q.; Xia, J. Y.; Zhang, Q.; Xiong, J. L.

    2012-04-01

    Undistortion methods based on perspective invariants play an important role in computer vision. The key of these methods is how to choose an proper measure to describe the perspective invariance of undistorted image features. We propose a new measure based on the homography between the control points in undistorted image and the pattern. The less the distortion is, the less the mapping error is. A new lens distortion calibration method is also put forward which uses this measure to search for accurate distortion parameters by iterative optimization. Comparing with other proposed measures based on perspective invariants, our measure is both concise and comprehensive. Both synthetic and real experiments show that our method performs well in accuracy and runtime.

  13. Gearbox Reliability Collaborative Bearing Calibration

    SciTech Connect

    van Dam, J.

    2011-10-01

    NREL has initiated the Gearbox Reliability Collaborative (GRC) to investigate the root cause of the low wind turbine gearbox reliability. The GRC follows a multi-pronged approach based on a collaborative of manufacturers, owners, researchers and consultants. The project combines analysis, field testing, dynamometer testing, condition monitoring, and the development and population of a gearbox failure database. At the core of the project are two 750kW gearboxes that have been redesigned and rebuilt so that they are representative of the multi-megawatt gearbox topology currently used in the industry. These gearboxes are heavily instrumented and are tested in the field and on the dynamometer. This report discusses the bearing calibrations of the gearboxes.

  14. A cryogenic infrared calibration target

    NASA Astrophysics Data System (ADS)

    Wollack, E. J.; Kinzer, R. E.; Rinehart, S. A.

    2014-04-01

    A compact cryogenic calibration target is presented that has a peak diffuse reflectance, R ? 0.003, from 800 to 4800 cm-1 (12 - 2 ?m). Upon expanding the spectral range under consideration to 400-10 000 cm-1 (25 - 1 ?m) the observed performance gracefully degrades to R ? 0.02 at the band edges. In the implementation described, a high-thermal-conductivity metallic substrate is textured with a pyramidal tiling and subsequently coated with a thin lossy dielectric coating that enables high absorption and thermal uniformity across the target. The resulting target assembly is lightweight, has a low-geometric profile, and has survived repeated thermal cycling from room temperature to ˜4 K. Basic design considerations, governing equations, and test data for realizing the structure described are provided. The optical properties of selected absorptive materials—Acktar Fractal Black, Aeroglaze Z306, and Stycast 2850 FT epoxy loaded with stainless steel powder—are characterized and presented.

  15. A cryogenic infrared calibration target.

    PubMed

    Wollack, E J; Kinzer, R E; Rinehart, S A

    2014-04-01

    A compact cryogenic calibration target is presented that has a peak diffuse reflectance, R ? 0.003, from 800?to?4800?cm(-1) (12 - 2??m). Upon expanding the spectral range under consideration to 400-10,000?cm(-1) (25 - 1??m) the observed performance gracefully degrades to R ? 0.02 at the band edges. In the implementation described, a high-thermal-conductivity metallic substrate is textured with a pyramidal tiling and subsequently coated with a thin lossy dielectric coating that enables high absorption and thermal uniformity across the target. The resulting target assembly is lightweight, has a low-geometric profile, and has survived repeated thermal cycling from room temperature to ?4 K. Basic design considerations, governing equations, and test data for realizing the structure described are provided. The optical properties of selected absorptive materials-Acktar Fractal Black, Aeroglaze Z306, and Stycast 2850 FT epoxy loaded with stainless steel powder-are characterized and presented. PMID:24784638

  16. Metrology - Beyond the Calibration Lab

    NASA Technical Reports Server (NTRS)

    Mimbs, Scott M.

    2008-01-01

    We rely on data from measurements every day; a gas-pump, a speedometer, and a supermarket weight scale are just three examples of measurements we use to make decisions. We generally accept the data from these measurements as "valid." One reason we can accept the data is the "legal metrology" requirements established and regulated by the government in matters of commerce. The measurement data used by NASA, other government agencies, and industry can be critical to decisions which affect everything from economic viability, to mission success, to the security of the nation. Measurement data can even affect life and death decisions. Metrology requirements must adequately provide for risks associated with these decisions. To do this, metrology must be integrated into all aspects of an industry including research, design, testing, and product acceptance. Metrology, the science of measurement, has traditionally focused on the calibration of instruments, and although instrument calibration is vital, it is only a part of the process that assures quality in measurement data. For example, measurements made in research can influence the fundamental premises that establish the design parameters, which then flow down to the manufacturing processes, and eventually impact the final product. Because a breakdown can occur anywhere within this cycle, measurement quality assurance has to be integrated into every part of the life-cycle process starting with the basic research and ending with the final product inspection process. The purpose of this paper is to discuss the role of metrology in the various phases of a product's life-cycle. For simplicity, the cycle will be divided in four broad phases, with discussions centering on metrology within NASA. .

  17. Camera calibration method for dimensional measurement of heavy forging in large scale

    NASA Astrophysics Data System (ADS)

    Liu, Bin; Hu, Chunhai; Song, Xiaoxue; Zhao, Zhenqing

    2009-07-01

    Camera calibration method plays an important role in the stereovision system to resolve the problems of dimensional measurement of heavy forging. Due to the intensive vibrating, the camera parameters must be calibrated every time after the action of the water press. This paper presents a method using the scene geometry to calibrate cameras. In the context of heavy machinery environments, the constraints which can be used are parallelism and orthogonality. These constraints lead to geometrically intuitive methods to calibrate the cameras. The huge forging equipment such as water press belongs to geometrically constrained object and insusceptible to vibrating, which gives natural prior knowledge and constraint conditions for 3-D reconstruction. The method focuses on the calibration of the extrinsic parameters which are subject to change since the effects of the workspace factors. The intrinsic parameters were calibrated in advance by an off-line method and were assumed as invariable. The results of simulation experiments demonstrate that the camera parameters could be calibrated effectively and achieve the real time need.

  18. Calibration of the NASA Glenn 8- by 6-Foot Supersonic Wind Tunnel (1996 and 1997 Tests)

    NASA Technical Reports Server (NTRS)

    Arrington, E. Allen

    2012-01-01

    There were several physical and operational changes made to the NASA Glenn Research Center 8- by 6-Foot Supersonic Wind Tunnel during the period of 1992 through 1996. Following each of these changes, a facility calibration was conducted to provide the required information to support the research test programs. Due to several factors (facility research test schedule, facility downtime and continued facility upgrades), a full test section calibration was not conducted until 1996. This calibration test incorporated all test section configurations and covered the existing operating range of the facility. However, near the end of that test entry, two of the vortex generators mounted on the compressor exit tailcone failed causing minor damage to the honeycomb flow straightener. The vortex generators were removed from the facility and calibration testing was terminated. A follow-up test entry was conducted in 1997 in order to fully calibrate the facility without the effects of the vortex generators and to provide a complete calibration of the newly expanded low speed operating range. During the 1997 tunnel entry, all planned test points required for a complete test section calibration were obtained. This data set included detailed in-plane and axial flow field distributions for use in quantifying the test section flow quality.

  19. Stepwise Regression Analysis of MDOE Balance Calibration Data Acquired at DNW

    NASA Technical Reports Server (NTRS)

    DeLoach, RIchard; Philipsen, Iwan

    2007-01-01

    This paper reports a comparison of two experiment design methods applied in the calibration of a strain-gage balance. One features a 734-point test matrix in which loads are varied systematically according to a method commonly applied in aerospace research and known in the literature of experiment design as One Factor At a Time (OFAT) testing. Two variations of an alternative experiment design were also executed on the same balance, each with different features of an MDOE experiment design. The Modern Design of Experiments (MDOE) is an integrated process of experiment design, execution, and analysis applied at NASA's Langley Research Center to achieve significant reductions in cycle time, direct operating cost, and experimental uncertainty in aerospace research generally and in balance calibration experiments specifically. Personnel in the Instrumentation and Controls Department of the German Dutch Wind Tunnels (DNW) have applied MDOE methods to evaluate them in the calibration of a balance using an automated calibration machine. The data have been sent to Langley Research Center for analysis and comparison. This paper reports key findings from this analysis. The chief result is that a 100-point calibration exploiting MDOE principles delivered quality comparable to a 700+ point OFAT calibration with significantly reduced cycle time and attendant savings in direct and indirect costs. While the DNW test matrices implemented key MDOE principles and produced excellent results, additional MDOE concepts implemented in balance calibrations at Langley Research Center are also identified and described.

  20. Inspection of feasible calibration conditions for UV radiometer detectors with the KI/KIO3 actinometer.

    PubMed

    Qiang, Zhimin; Li, Wentao; Li, Mengkai; Bolton, James R; Qu, Jiuhui

    2015-01-01

    UV radiometers are widely employed for irradiance measurements, but their periodical calibrations not only induce an extra cost but also are time-consuming. In this study, the KI/KIO3 actinometer was applied to calibrate UV radiometer detectors at 254 nm with a quasi-collimated beam apparatus equipped with a low-pressure UV lamp, and feasible calibration conditions were identified. Results indicate that a washer constraining the UV light was indispensable, while the size (10 or 50 mL) of a beaker containing the actinometer solution had little influence when a proper washer was used. The absorption or reflection of UV light by the internal beaker wall led to an underestimation or overestimation of the irradiance determined by the KI/KIO3 actinometer, respectively. The proper range of the washer internal diameter could be obtained via mathematical analysis. A radiometer with a longer service time showed a greater calibration factor. To minimize the interference from the inner wall reflection of the collimating tube, calibrations should be conducted at positions far enough away from the tube bottom. This study demonstrates that after the feasible calibration conditions are identified, the KI/KIO3 actinometer can be applied readily to calibrate UV radiometer detectors at 254 nm. PMID:25283349