Science.gov

Sample records for syringe calibration factors

  1. [Technology of preparing gauges for calibration of medical syringe cylinders].

    PubMed

    Belavin, N F; Vaĭner, E L

    1979-01-01

    Thermal treatment substantially influences the resistance of calibres used in mollification (vacuum calibrating) of glass cylinders for medical syringes, the highest resistance of calibres made of the XH32T alloy and the 12X18H10T steel being achieved through their preliminary annealing in the argon atmosphere. The quality of manufactured syringes is affected also by wrong calibres shape and, formostly, by their out-of-roundness, whose degree in individual cases reaches 2--3 micrometer. PMID:763104

  2. Computerized determination of pneumotachometer characteristics using a calibrated syringe.

    PubMed

    Yeh, M P; Gardner, R M; Adams, T D; Yanowitz, F G

    1982-07-01

    A computerized method has been developed to determine the conductance characteristics of pneumotachometers. Conductance values of the flowmeter, which correspond to all pressure values, can be determined by a weighted averaging technique, when multiple strokes of a precision 3-liter calibrated syringe are used. The conductance values then allow the measured differential pressures to be converted, point by point, into flows. The accuracy of measured volumes is within +/- 0.5% for a 100-stroke calibration process, and calibration with 50 strokes provides +/- 1% accuracy. The method improves the accuracy of the on-line measurements of ventilation. O2 consumption, and CO2 production during exercise. PMID:7118642

  3. Social factors related to syringe sharing among injecting partners: a focus on gender.

    PubMed

    Sherman, S G; Latkin, C A; Gielen, A C

    2001-12-01

    The study of social networks has become an increasingly utilized method of examining the relationship between injection drug users' social environment and risk of HIV. This study examined relational aspects of two injection drug users (IDUs) within a single social network as they relate to sharing syringes. Data presented in this study were derived from baseline interviews of 508 IDUs from Baltimore, MD. Analyses were performed separately for male and female participants in an effort to understand gender differences in social aspects of syringe sharing. Among this sample, women shared syringes with a significantly higher percentage of injecting partners compared to men. In separate multilevel logistic regression models, significant variables associated with males' and females' syringe sharing were: sharing drugs daily with female injecting partners, injecting partners' provision of drugs when indexes' were withdrawing, being sexual partners, and injecting partners' injecting speedballs. Factors associated with male injecting dyads sharing of syringes were: being kin, injecting partners' injection of heroin and daily drug use, and drinking alcohol together. Results from this study demonstrate the usefulness of examining relationship characteristics of injecting dyads related to syringe sharing as they differ between men and women. PMID:11794586

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

    PubMed Central

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

    2012-01-01

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

  5. Neighborhood History as a Factor Shaping Syringe Distribution Networks Among Drug Users at a U.S. Syringe Exchange1

    PubMed Central

    Braine, Naomi; Acker, Caroline; Goldblatt, Cullen; Yi, Huso; Friedman, Samuel; DesJarlais, Don C.

    2008-01-01

    Throughout the US, high-visibility drug markets are concentrated in neighborhoods with few economic opportunities, while drug buyers/users are widely dispersed. A study of Pittsburgh Syringe Exchange participants provides data on travel between and network linkages across neighborhoods with different levels of drug activity. There are distinct racial patterns to syringe distribution activity within networks and across neighborhoods. Pittsburgh’s history suggests these patterns emerge from historical patterns of social and economic development. Study data demonstrate the ability of IDUs to form long term social ties across racial and geographic boundaries and use them to reduce the risk of HIV transmission. PMID:19578475

  6. Social and Political Factors Predicting the Presence of Syringe Exchange Programs in 96 US Metropolitan Areas

    PubMed Central

    Tempalski, Barbara; Flom, Peter L.; Friedman, Samuel R.; Des Jarlais, Don C.; Friedman, Judith J.; McKnight, Courtney; Friedman, Risa

    2007-01-01

    Community activism can be important in shaping public health policies. For example, political pressure and direct action from grassroots activists have been central to the formation of syringe exchange programs (SEPs) in the United States. We explored why SEPs are present in some localities but not others, hypothesizing that programs are unevenly distributed across geographic areas as a result of political, socioeconomic, and organizational characteristics of localities, including needs, resources, and local opposition. We examined the effects of these factors on whether SEPs were present in different US metropolitan statistical areas in 2000. Predictors of the presence of an SEP included percentage of the population with a college education, the existence of local AIDS Coalition to Unleash Power (ACT UP) chapters, and the percentage of men who have sex with men in the population. Need was not a predictor. PMID:17267732

  7. 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

  8. Continuing HIV Risk in New York City Injection Drug Users: The Association of Syringe Source and Syringe Sharing

    PubMed Central

    Jenness, Samuel M.; Hagan, Holly; Liu, Kai-Lih; Wendel, Travis; Murrill, Christopher S.

    2016-01-01

    Sterile syringe access is an important means to reduce HIV risk, but many injection drug users (IDU) who obtain syringes from sterile sources continue to share syringes. We examined the factors associated with continuing syringe sharing in New York City. We recruited 500 active IDU in 2005 through respondent-driven sampling. In multiple logistic regression, not obtaining all syringes in the past year exclusively from sterile sources was associated with increased syringe sharing. Ensuring adequate syringe availability as well as engaging and retaining nonusers and inconsistent users in sterile syringe services may increase sterile syringe access and decrease syringe sharing. PMID:21303239

  9. Social Network-Related Risk Factors for Bloodborne Virus Infections Among Injection Drug Users Receiving Syringes through Secondary Exchange

    PubMed Central

    Cox, Joseph; Boivin, Jean-François; Platt, Robert W.; Jolly, Ann M.

    2007-01-01

    Secondary syringe exchange (SSE) refers to the exchange of sterile syringes between injection drug users (IDUs). To date there has been limited examination of SSE in relation to the social networks of IDUs. This study aimed to identify characteristics of drug injecting networks associated with the receipt of syringes through SSE. Active IDUs were recruited from syringe exchange and methadone treatment programs in Montreal, Canada, between April 2004 and January 2005. Information on each participant and on their drug-injecting networks was elicited using a structured, interviewer-administered questionnaire. Subjects’ network characteristics were examined in relation to SSE using regression models with generalized estimating equations. Of 218 participants, 126 were SSE recipients with 186 IDUs in their injecting networks. The 92 non-recipients reported 188 network IDUs. Networks of SSE recipients and non-recipients were similar with regard to network size and demographics of network members. In multivariate analyses adjusted for age and gender, SSE recipients were more likely than non-recipients to self-report being HIV-positive (OR = 3.56 [1.54–8.23]); require or provide help with injecting (OR = 3.74 [2.01–6.95]); have a social network member who is a sexual partner (OR = 1.90 [1.11–3.24]), who currently attends a syringe exchange or methadone program (OR = 2.33 [1.16–4.70]), injects daily (OR = 1.77 [1.11–2.84]), and shares syringes with the subject (OR = 2.24 [1.13–4.46]). SSE is associated with several injection-related risk factors that could be used to help focus public health interventions for risk reduction. Since SSE offers an opportunity for the dissemination of important prevention messages, SSE-based networks should be used to improve public health interventions. This approach can optimize the benefits of SSE while minimizing the potential risks associated with the practice of secondary exchange. PMID:18038211

  10. Protecting Gas Chromatographic Syringes

    NASA Astrophysics Data System (ADS)

    Ruekberg, Ben

    1995-12-01

    This article describes the construction of a device which protects gas chromatographic syringes. The device lessens the likelihood of syringes rolling off tables and breaking. If the syringe is dropped, the glass barrel is less apt to be struck and shattered.

  11. SWIR calibration of Spectralon reflectance factor

    NASA Astrophysics Data System (ADS)

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

    2011-11-01

    Satellite instruments operating in the reflective solar wavelength region require accurate and precise determination of the Bidirectional Reflectance Factor (BRF) of laboratory-based diffusers used in their pre-flight and on-orbit radiometric calibrations. BRF measurements are required throughout the reflected-solar spectrum from the ultraviolet through the shortwave infrared. Spectralon diffusers are commonly used as a reflectance standard for bidirectional and hemispherical geometries. The Diffuser Calibration Laboratory (DCaL) at NASA's Goddard Space Flight Center is a secondary calibration facility with reflectance measurements traceable to those made by the Spectral Tri-function Automated Reference Reflectometer (STARR) facility at the National Institute of Standards and Technology (NIST). For more than two decades, the DCaL has provided numerous NASA projects with BRF data in the ultraviolet (UV), visible (VIS) and the Near InfraRed (NIR) spectral regions. Presented in this paper are measurements of BRF from 1475 nm to 1625 nm obtained using an indium gallium arsenide detector and a tunable coherent light source. The sample was a 50.8 mm (2 in) diameter, 99% white Spectralon target. The BRF results are discussed and compared to empirically generated data from a model based on NIST certified values of 6°directional-hemispherical spectral reflectance factors from 900 nm to 2500 nm. Employing a new NIST capability for measuring bidirectional reflectance using a cooled, extended InGaAs detector, BRF calibration measurements of the same sample were also made using NIST's STARR from 1475 nm to 1625 nm at an incident angle of 0° and at viewing angle of 45°. The total combined uncertainty for BRF in this ShortWave Infrared (SWIR) range is less than 1%. This measurement capability will evolve into a BRF calibration service in SWIR region in support of NASA remote sensing missions.

  12. Spatial access to sterile syringes and the odds of injecting with an unsterile syringe among injectors: a longitudinal multilevel study.

    PubMed

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

    2012-08-01

    Despite the 2010 repeal of the ban on spending federal monies to fund syringe exchange programs (SEPs) in the U.S.A., these interventions--and specifically SEP site locations--remain controversial. To further inform discussions about the location of SEP sites, this longitudinal multilevel study investigates the relationship between spatial access to sterile syringes distributed by SEPs in New York City (NYC) United Hospital Fund (UHF) districts and injecting with an unsterile syringe among injectors over time (1995-2006). Annual measures of spatial access to syringes in each UHF district (N = 42) were created using data on SEP site locations and site-specific syringe distribution data. Individual-level data on unsterile injecting among injectors (N = 4,067) living in these districts, and on individual-level covariates, were drawn from the Risk Factors study, an ongoing cross-sectional study of NYC drug users. We used multilevel models to explore the relationship of district-level access to syringes to the odds of injecting with an unsterile syringe in >75% of injection events in the past 6 months, and to test whether this relationship varied by district-level arrest rates (per 1,000 residents) for drug and drug paraphernalia possession. The relationship between district-level access to syringes and the odds of injecting with an unsterile syringe depended on district-level arrest rates. In districts with low baseline arrest rates, better syringe access was associated with a decline in the odds of frequently injecting with an unsterile syringe (AOR, 0.95). In districts with no baseline syringe access, higher arrest rates were associated with increased odds of frequently injecting with an unsterile syringe (AOR, 1.02) When both interventions were present, arrest rates eroded the protective effects of spatial access to syringes. Spatial access to syringes in small geographic areas appears to reduce the odds of injecting with an unsterile syringe among local

  13. 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

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

    NASA Astrophysics Data System (ADS)

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

    2007-10-01

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

  15. 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

  16. 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 μm. 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.

  17. 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.

  18. Gas ampoule-syringe

    DOEpatents

    Gay, Don D.

    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.

  19. 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

  20. Automated application of calibration factors on telemetered data

    SciTech Connect

    Kalibjian, J.R.; Voss, T.J.; Yio, J.J.

    1993-04-26

    A long standing problem in telemetry post processing is the application of correct calibration factors to telemetered data generated on a system which has had a history of hardware changes. These calibration problems become most exacerbated when old test data is being examined and there is uncertainty as to hardware configuration at the time of the test. In this paper a mechanism for introducing a high degree of reliability in the application of calibration factors is described in an implementation done for Brilliant Pebbles Flight Experiment Three (FE-3).

  1. Syringe exchange programs: lowering the transmission of syringe-borne diseases and beyond.

    PubMed Central

    Heimer, R

    1998-01-01

    OBJECTIVE: This chapter attempts to describe the factors influencing the transmission of syringe-born viruses, to review the effects of syringe exchange programs (SEPs) in terms of these factors, and to explore the gamut of health-promoting activities of SEPs. RESULTS: The chapter is divided into six sections: biological factors in syringe-borne viral transmission, behavior and viral transmission, quantifying viral transmission, preventing viral transmission, impediments to preventing viral transmission, and research for preventing viral transmission. Understanding how biological and behavioral factors influence transmission of human immunodeficiency virus (HIV) and hepatitis builds a framework to investigate the epidemiology and the impact of SEPs on disease transmission. Even under circumstances in which these programs do not appear to be effective, understanding the implications of the biological and behavioral factors can contribute to our understanding of program benefits and limitations. Furthermore, program benefits may not be restricted to direct effects on disease transmission. Many programs offer services to drug injectors that include risk reduction training, facilitated entry into substance abuse treatment, and medical care. CONCLUSIONS: SEPs can reduce the transmission of syringe-borne viruses without increasing illicit drug use. However, lack of resources, acceptance, and consequently, protection of many of those at risk when they are most vulnerable have hampered program effectiveness. New studies need to be designed to explicate the full measure of program benefit within covered communities and identify the means by which SEPs can expand benefit to individuals at greatest risk. PMID:9722811

  2. 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)

  3. Syringe driver in terminal care.

    PubMed Central

    Dover, S B

    1987-01-01

    Continuous subcutaneous infusions of drugs by syringe driver are used often and successfully in the terminal care of patients when drugs cannot be given orally. Diamorphine is the opioid of choice because of its high solubility. If other drugs such as antiemetics, anticholinergics, sedatives, or steroids are required they may also be given by syringe driver. This method is particularly useful for domiciliary care, where the practical difficulties of providing regular parenteral analgesia are otherwise formidable. PMID:3103774

  4. The syringe gap: an assessment of sterile syringe need and acquisition among syringe exchange program participants in New York City

    PubMed Central

    Heller, Daliah I; Paone, Denise; Siegler, Anne; Karpati, Adam

    2009-01-01

    Background Programmatic data from New York City syringe exchange programs suggest that many clients visit the programs infrequently and take few syringes per transaction, while separate survey data from individuals using these programs indicate that frequent injecting – at least daily – is common. Together, these data suggest a possible "syringe gap" between the number of injections performed by users and the number of syringes they are receiving from programs for those injections. Methods We surveyed a convenience sample of 478 injecting drug users in New York City at syringe exchange programs to determine whether program syringe coverage was adequate to support safer injecting practices in this group. Results Respondents reported injecting a median of 60 times per month, visiting the syringe exchange program a median of 4 times per month, and obtaining a median of 10 syringes per transaction; more than one in four reported reusing syringes. Fifty-four percent of participants reported receiving fewer syringes than their number of injections per month. Receiving an inadequate number of syringes was more frequently reported by younger and homeless injectors, and by those who reported public injecting in the past month. Conclusion To improve syringe coverage and reduce syringe sharing, programs should target younger and homeless drug users, adopt non-restrictive syringe uptake policies, and establish better relationships with law enforcement and homeless services. The potential for safe injecting facilities should be explored, to address the prevalence of public injecting and resolve the 'syringe gap' for injecting drug users. PMID:19138414

  5. jasonSWIR Calibration of Spectralon Reflectance Factor

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  6. Calibration of Gyros with Temperature Dependent Scale Factors

    NASA Technical Reports Server (NTRS)

    Belur, Sheela V.; Harman, Richard

    2001-01-01

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

  7. Individual and neighborhood-level factors associated with non-prescription counseling in pharmacies participating in the New York State Expanded Syringe Access Program (ESAP)

    PubMed Central

    Rivera, Alexis V; Blaney, Shannon; Crawford, Natalie D; White, Kellee; Stern, Rachel J; Amesty, Silvia; Fuller, Crystal

    2013-01-01

    Objective To determine the individual- and neighborhood-level predictors of frequent non-prescription in-pharmacy counseling. Design Cross-sectional survey Setting 130 pharmacies registered in the Expanded Syringe Access Program (ESAP) in New York City. Participants 477 pharmacists, non-pharmacist owner/managers, and technicians/clerks. Main outcome measures Frequent counseling on medical conditions, health insurance, and other products. Results Technicians were less likely than pharmacists to provide frequent counseling on medical conditions or health insurance. In terms of neighborhood-level characteristics, pharmacies in areas of high employment disability were less likely to provide frequent health insurance counseling and pharmacies in areas with higher deprivation were more likely to provide counseling on other products. Conclusion ESAP pharmacy staff is a frequent source of non-prescription counseling for their patients/customers in disadvantaged neighborhoods of NYC. These findings suggest that ESAP pharmacy staff may be amenable to providing relevant counseling services to injection drug using syringe customers and warrants further investigation. PMID:20833615

  8. 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)

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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

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

    PubMed

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

    2014-01-01

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

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

    PubMed

    Tooke, L J; Howell, L

    2014-07-01

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

  17. The cleaning of instruments and syringes

    PubMed Central

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

    1965-01-01

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

  18. Who purchases nonprescription syringes? Characterizing customers of the Expanded Syringe Access Program (ESAP).

    PubMed

    Battles, Haven B; Rowe, Kirsten A; Ortega-Peluso, Christina; Klein, Susan J; Tesoriero, James M

    2009-11-01

    This study represents the first attempt in the USA to survey pharmacy nonprescription syringe customers at their point of purchase. We surveyed 62 individuals purchasing nonprescription syringes in seven pharmacies located in NYC and Albany, NY, USA. Three quarters of respondents purchased for illicit use, and 36% purchased for medical use, with differences found by race and gender. Half got their syringes from pharmacies "most of the time." Half had ever been refused a syringe purchase in a NYS pharmacy, with men, Blacks, and Hispanics reporting higher levels of refusals than women or whites. Two thirds reported syringe reuse but very few reported sharing. While approximately one quarter safely obtained and disposed of syringes "most of the time," two thirds used both safe and unsafe methods. Pharmacy-based syringe access programs are essential in areas not served by syringe exchanges. PMID:19434499

  19. 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)

  20. Syringe liposculpture: a two-year experience.

    PubMed

    Toledo, L S

    1991-01-01

    Syringe liposculpture is a method that combines two relatively new techniques of plastic surgery: syringe liposuction and fat grafting. We can reshape the face and the body by removing localized fat deposits and reinjecting this fat where needed. When we do not reinject, we call the technique reduction liposculpture. In 1989 we introduced a new technique--superficial syringe liposculpture--to treat patients with flaccid skin, superficial irregularities or depressions, "cellulite," and liposuction sequelae. The technique combines syringe liposculpture, superficial liposuction, and our method of treating skin irregularities by breaking the fibrous adherences and injecting fat superficially. PMID:1950806

  1. Calibration

    NASA Astrophysics Data System (ADS)

    Kunze, Hans-Joachim

    Commercial spectrographic systems are usually supplied with some wave-length calibration, but it is essential that the experimenter performs his own calibration for reliable measurements. A number of sources emitting well-known emission lines are available, and the best values of their wavelengths may be taken from data banks accessible on the internet. Data have been critically evaluated for many decades by the National Institute of Standards and Technology (NIST) of the USA [13], see also p. 3. Special data bases have been established by the astronomy and fusion communities (Appendix B).

  2. Fluid delivery from infusion-pump syringes.

    PubMed

    Carl, J L; Erstad, B L; Murphy, J E; Slack, M K

    1995-07-01

    Fluid-delivery rates of five small-volume infusion-pump syringes were compared. The study consisted of a comparison of the infusion-pump syringes in their respective infusion pumps (1) set for continuous delivery at 1 mL/hr, (2) set for continuous delivery at 3 mL/hr, and (3) set to deliver 1-mL bolus volumes during continuous delivery at 4 mL/hr. The Life-care prefilled 30-mL syringe (Abbott), the DBL 30-mL syringe no. 770205 (DBL Inc.), and the Pump-Jet 30-mL syringe no. 1931 (International Medication Systems) were tested in the Lifecare PCA Plus II infusion pump no. 4100 (Abbott). The 30-mL Pump-Jet syringe no. 1911 (International Medication Systems) and the DBL 30-mL syringe no. 709700 (DBL Inc.) were tested in the Stratofuse PCA infusion pump (Baxter). The infusion pumps were set to deliver fluid continuously at 1 mL/hr for 30 hours, and the solutions were collected separately and weighed. The procedure was repeated with the infusion rate set at 3 mL/hr for 10 hours. For the third part of the study, each syringe was tested to deliver 1-mL boluses with 0, 5, 15, and 25 mL removed from the syringe. The solutions were collected and weighed before and after each bolus was delivered. The volume of solution collected was calculated by using the specific gravity of the solution. The syringes delivered significantly different volumes during the first hour of infusion at both the 1- and 3-mL/hr rates. Differences also existed across time for most of the syringes. Bolus volumes varied greatly after infusion of 0 or 5 mL of fluid but were acceptable for the remainder of the infusions.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7671041

  3. Slow viscous flow in a syringe.

    PubMed

    Watson, L T; Billups, S C; Wang, C Y; Everett, E A

    1986-11-01

    The slow viscous flow in a syringe is modeled by the quasi-steady axisymmetric Stokes equation with a point sink for the needle hole. The governing equations are approximated using nonstandard finite difference formulas optimized for the boundary conditions, and solved numerically using a SOR technique. Streamlines and pressure profiles are computed for a variety of syringe configurations. PMID:3795876

  4. 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 and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL HOSPITAL AND PERSONAL USE DEVICES General Hospital and Personal Use Miscellaneous Devices § 880.6960 Irrigating syringe....

  5. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 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 that... connector (nozzle) for fitting the female connector (hub) of a hypodermic single lumen needle. The device...

  6. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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 that... connector (nozzle) for fitting the female connector (hub) of a hypodermic single lumen needle. The device...

  7. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 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 that... connector (nozzle) for fitting the female connector (hub) of a hypodermic single lumen needle. The device...

  8. 21 CFR 880.5860 - Piston syringe.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 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 that... connector (nozzle) for fitting the female connector (hub) of a hypodermic single lumen needle. The device...

  9. Particulate contamination of sterile syringes and needles.

    PubMed

    Taylor, S A

    1982-08-01

    Commercially available sterile needles and syringes have been examined for particulate contamination using the Hiac light blockage technique. The number of particles delivered was small compared with the total number permitted for large volume parenterals. Where syringes are used in particle counting techniques, the contribution of particles should be taken into account. PMID:6126558

  10. A multistate trial of pharmacy syringe purchase.

    PubMed

    Compton, Wilson M; Horton, Joe C; Cottler, Linda B; Booth, Robert; Leukefeld, Carl G; Singer, Merrill; Cunningham-Williams, Renee; Reich, Wendy; Fortuin Corsi, Karen; Staton, Michele; Fink, Joseph L; Stopka, Thomas J; Spitznagel, Edward L

    2004-12-01

    Pharmacies are a potential site for access to sterile syringes as a means for preventing human immunodeficiency virus (HIV), but the type and extent of their utility is uncertain. To examine pharmacy syringe purchase, we conducted a standardized, multistate study in urban and rural areas of four states in which attempts to purchase syringes were documented. Of 1,600 overall purchase attempts, 35% were refused. Colorado (25%) and Connecticut (28%) had significantly lower rates of refusal than Kentucky (41%) and Missouri (47%). Furthermore, urban settings had higher rates of refusal (40%) than rural settings (31%, P < .01). Race and gender did not have a consistent impact on rates of refusal. Despite potential advantages of pharmacies as sites for access to sterile syringes, pharmacy purchase of syringes faces significant obstacles in terms of the practices in different jurisdictions. PMID:15466847

  11. The association of syringe type and syringe cleaning with HCV infection among IDUs in Budapest, Hungary.

    PubMed

    Gyarmathy, V Anna; Neaigus, Alan; Mitchell, Mary M; Ujhelyi, Eszter

    2009-03-01

    We assessed whether syringe type, syringe cleaning and distributive syringe sharing were associated with self-reported and laboratory-confirmed HCV infection among Hungarian IDUs. Injecting drug users (N=215) were recruited from non-treatment settings in Budapest, Hungary between October 2005 and December 2006. Multivariate logistic regression models identified correlates of self-report of being HCV infected and testing positive for HCV. While 37% tested positive for HCV, 14% of the total (39% of those who tested positive) self-reported being HCV infected. Using any two-piece syringes was significantly associated with self-reported HCV infection, while distributive syringe sharing was not associated with self-report of being HCV infected. Engaging in receptive sharing of only one-piece syringes but always cleaning before reuse was not associated with testing HCV positive, while any receptive sharing of only one-piece syringes and not always cleaning before reuse was significantly associated with testing HCV positive. Sharing cookers and squirting drugs from one syringe into another syringe were not associated with testing HCV positive. The high percent of those HCV infected who did not know they were infected highlights the need to provide better access to confidential testing and counseling services. Counseling should emphasize secondary prevention of HCV among HCV infected IDUs. Our findings also indicate that syringe type and syringe cleaning practices may play a role in HCV transmission. Ethnographic research should identify the reasons why IDUs may use two-piece syringes and suggest means to reduce their use. Thorough cleaning of one-piece syringes when sterile syringes are unavailable may be an efficient way to reduce the risk of HCV infection. PMID:19058925

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

    PubMed Central

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

    2010-01-01

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

  13. Source geometry factors for HDR 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.

  14. Syringe Disposal Among Injection Drug Users in San Francisco

    PubMed Central

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

    2011-01-01

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

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

    SciTech Connect

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

    2003-01-28

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

  16. Syringe exchange programs --- United States, 2008.

    PubMed

    2010-11-19

    Persons who inject drugs should use a new, sterile needle and syringe for each injection. Syringe exchange programs (SEPs) provide free sterile syringes and collect used syringes from injection-drug users (IDUs) to reduce transmission of bloodborne pathogens, including human immunodeficiency virus (HIV), hepatitis B virus, and hepatitis C virus (HCV). As of March 2009, a total of 184 SEPs were known to be operating in 36 states, the District of Columbia (DC), and Puerto Rico (North American Syringe Exchange Network [NASEN], unpublished data, 2009). Of these, 123 (67%) SEP directors participated in a mail/telephone survey conducted by NASEN and Beth Israel Medical Center (New York, New York) that covered program operations for the calendar year 2008. To characterize SEPs in the United States, this report summarizes the findings from that survey and compares them with previous SEP survey results from the period 1994-2007. In 2008, the 123 SEPs reported exchanging 29.1 million syringes and had budgets totaling $21.3 million, of which 79% came from state and local governments. Most of the SEPs reported offering preventive health and clinical services in addition to basic syringe exchange: 87% offered HIV counseling and testing, 65% offered hepatitis C counseling and testing, 55% offered sexually transmitted disease screening, and 31% offered tuberculosis screening; 89% provided referrals to substance abuse treatment. Providing comprehensive prevention services and referrals to IDUs, such as those offered by many SEPs, can help reduce the spread of bloodborne infections and should increase access to health care and substance abuse treatment, thus serving as an effective public health approach for this population. PMID:21085091

  17. 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.

  18. Exponential gradient maker using a disposable syringe.

    PubMed

    Domingo, A

    1990-08-15

    With a simple modification, any disposable syringe can become a reliable and easy to use exponential gradient maker. The modification consists of two notches, made with a razor blade, in the borders of the rubber sealing tip of the plunger. A clamp in the tube connected to the syringe allows control over solution flow. With the clamp prohibiting drainage, the body of the syringe is filled with the desired volume of starting solution I. A magnetic stir bar, small enough to spin inside the syringe is included. The notched plunger is introduced until no air space remains. This forms the fixed volume, closed mixing chamber, while the rest of the volume of the syringe forms the open chamber. The two chambers are connected through the notches in the plunger. The ending solution II is poured after the introduction of the plunger. Opening the clamp allows solution I in the closed chamber to flow out, and the solution II in the open chamber flows through the notches and mixes with solution I. This exponential gradient maker can be reused many times, but the low cost of the components makes it potentially disposable. This feature is especially useful when using toxic chemicals, or when pouring polyacrylamide gradient gels, since the apparatus may be disposed of after contamination or eventual polymerization. PMID:2278394

  19. 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.

  20. Characterization of a Monoclonal Antibody against Syringate Derivatives: Application of Immunochemical Detection of Methyl Syringate in Honey.

    PubMed

    Kato, Yoji; Fujinaka, Rie; Juri, Maki; Yoshiki, Yui; Ishisaka, Akari; Kitamoto, Noritoshi; Nitta, Yoko; Ishikawa, Hirohito

    2016-08-24

    Syringic acid is one of the key skeletal structures of plant-derived chemicals. The derivatives of syringic acid have certain biological functions. In this study, a monoclonal antibody to syringic acid-based phytochemicals was prepared and characterized. The obtained antibody reacted with methyl syringate, syringic acid, and leonurine. Methyl syringate is a characteristic compound found in manuka honey, other honey varieties, and plants. Manuka honey was fractionated using HPLC, and the reactivity of the fractions with the antibody was examined. The antibody reacted with the fraction in which methyl syringate was eluted. The amount of methyl syringate in honeys as estimated by ELISA using the antibody had a good linearity compared with that estimated by HPLC. These results suggest that the antibody is applicable for the immunochemical detection of syringic acid derivatives in plants and foods. PMID:27477590

  1. Prevalence and predictors of transitions to and away from syringe exchange use over time in 3 US cities with varied syringe dispensing policies

    PubMed Central

    Green, Traci C.; Bluthenthal, Ricky N.; Singer, Merrill; Beletsky, Leo; Grau, Lauretta E.; Marshall, Patricia; Heimer, Robert

    2010-01-01

    Syringe exchange programs (SEPs) can reduce HIV risk among injecting drug users (IDUs) but their use may depend heavily on contextual factors such as local syringe policies. The frequency and predictors of transitioning over time to and from direct, indirect, and non-use of SEPs are unknown. We sought, over one year, to: (1) quantify and characterize transition probabilities of SEP attendance typologies; (2) identify factors associated with (a) change in typology, and (b) becoming and maintaining direct SEP use; and (3) quantify and characterize transition probabilities of SEP attendance before and after changes in policy designed to increase access. Using data collected from 583 IDUs participating in a three-city cohort study of SEPs, we conducted a latent transition analysis and multinomial regressions. Three typologies were detected: Direct SEP users, Indirect SEP users and Isolated IDUs. Transitions to direct SEP use were most prevalent. Factors associated with becoming or maintaining direct SEP use were female sex, Latino ethnicity, fewer injections per syringe, homelessness, recruitment city, injecting speedballs (cocaine and heroin), and police contact involving drug paraphernalia possession. Similar factors influenced transitions in the syringe policy change analysis. Policy change cities experienced an increase in Indirect SEP users (43% to 51%) with little increased direct use (29% to 31%). We found that, over time, IDUs tended to become Direct SEP users. Policies improving syringe availability influenced SEP use by increasing secondary syringe exchange. Interactions with police around drug paraphernalia may encourage SEP use for some IDUs and may provide opportunities for other health interventions. PMID:20537814

  2. The impact of syringe deregulation on sources of syringes for injection drug users: preliminary findings.

    PubMed

    Deren, Sherry; Cleland, Charles M; Fuller, Crystal; Kang, Sung-Yeon; Des Jarlais, Don C; Vlahov, David

    2006-11-01

    In 2001, New York State enacted legislation to allow the provision of syringes by pharmacies and healthcare providers without prescription (ESAP, the Expanded Syringe Access Demonstration Program). A longitudinal study of IDUs (n=130) found that pre-ESAP, about half used only the safest source (needle exchange programs [NEPs]). Post-ESAP implementation, ESAP sources were initiated by 14%. Frequency of injection was related to ESAP use and those who used unsafe (or possibly unsafe) sources were as likely to use ESAP as those who had previously used only NEPs. The findings indicate that providing multiple sources of safe syringes for IDUs is necessary. PMID:16642418

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

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

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

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

    PubMed

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

    2015-01-21

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

  5. 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)

  6. 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)

  7. Safe practice in syringe pump management.

    PubMed

    Mukoreka, Juliette; Sisay, Isatta

    Syringe pumps offer an alternative route for delivering medicine when the oral route cannot be used. This is particularly important for patients receiving palliative care, for whom a continuous infusion of medication can improve symptom control. This article explains how to administer drugs safely using these devices. PMID:26182586

  8. 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.

  9. Impact of medications on bacterial growth in syringes.

    PubMed

    Kerenyi, M; Borza, Z; Csontos, C; Ittzes, B; Batai, I

    2011-11-01

    Syringes used to administer intravenous medications in an intensive care unit were cultured, and the isolates were compared with those from positive blood cultures from the same patients. The overall contamination rate was 16%, and syringes used for drugs such as insulin, which support bacterial growth, had higher contamination rates. All syringes should be changed routinely after 6h. PMID:21864939

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

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Labeling of vials and syringes. 35.69 Section 35.69 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL General Technical Requirements § 35.69 Labeling of vials and syringes. Each syringe and vial that contains unsealed byproduct material must...

  11. Precision evaluation of calibration factor of a superconducting gravimeter using an absolute gravimeter

    NASA Astrophysics Data System (ADS)

    Feng, Jin-yang; Wu, Shu-qing; Li, Chun-jian; Su, Duo-wu; Xu, Jin-yi; Yu, Mei

    2016-01-01

    The precision of the calibration factor of a superconducting gravimeter (SG) using an absolute gravimeter (AG) is analyzed based on linear least square fitting and error propagation theory and factors affecting the accuracy are discussed. It can improve the accuracy to choose the observation period of solid tide as a significant change or increase the calibration time. Simulation is carried out based on synthetic gravity tides calculated with T-soft at observed site from Aug. 14th to Sept. 2nd in 2014. The result indicates that the highest precision using half a day's observation data is below 0.28% and the precision exponentially increases with the increase of peak-to-peak gravity change. The comparison of results obtained from the same observation time indicated that using properly selected observation data has more beneficial on the improvement of precision. Finally, the calibration experiment of the SG iGrav-012 is introduced and the calibration factor is determined for the first time using AG FG5X-249. With 2.5 days' data properly selected from solid tide period with large tidal amplitude, the determined calibration factor of iGrav-012 is (-92.54423+/-0.13616) μGal/V (1μGal=10-8m/s2), with the relative accuracy of about 0.15%.

  12. 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.

  13. Comparison of injection drug users accessing syringes from pharmacies, syringe exchange programs, and other syringe sources to inform targeted HIV prevention and intervention strategies

    PubMed Central

    Rudolph, Abby E.; Crawford, Natalie D.; Ompad, Danielle C.; Benjamin, Ebele O.; Stern, Rachel J.; Fuller, Crystal M.

    2011-01-01

    Objective In New York, syringe exchange programs (SEPs) and pharmacies provide syringe access for IDUs but may be unable to meet the needs of all IDUs. This analysis aims to describe IDUs who access syringes through different outlets to help inform the prevention needs of IDUs who under-utilize safe syringe sources in a city where syringe availability is high relative to other U.S. cities. Design Cross-sectional study Setting New York City (2005–2007) Participants 285 IDUs recruited using street-intercept sampling Intervention(s) Not Applicable Main outcome measure(s) IDUs using SEPs, pharmacies, or other outlets as a primary syringe source were compared by sociodemographic characteristics, injection practices and medical service utilization. Results Chi-square tests and polytomous logistic regression were used to compare IDUs with different self-reported primary syringe sources used 6 months prior to study entry. Compared with IDUs using other syringe sources, those using primarily SEPs were less likely to be Black (AOR:0.26 95%CI:0.11–0.57), more likely to inject daily (AOR:3.32; 95%CI:1.58–6.98), and more likely to inject with a new syringe (AOR:2.68; 95%CI:1.30–5.54). Compared with IDUs using other syringe sources, those using primarily pharmacies were less likely to be Black (AOR:0.39; 95%CI0.17–0.90). Conclusion These data suggest that pharmacies and SEPs may be reaching different populations of IDUs and highlight a sub-population of highly marginalized IDUs (Black and infrequent injectors) who are under-utilizing safe syringe sources in New York City. Targeted interventions are needed to reduce racial disparities and increase utilization of safe syringe outlets. PMID:20199954

  14. Comparative evaluation of endodontic pressure syringe, insulin syringe, jiffy tube, and local anesthetic syringe in obturation of primary teeth: An in vitro study

    PubMed Central

    Hiremath, Mallayya C.; Srivastava, Pooja

    2016-01-01

    Purpose: The purpose of this in vitro study was to compare four methods of root canal obturation in primary teeth using conventional radiography. Materials and Methods: A total of 96 root canals of primary molars were prepared and obturated with zinc oxide eugenol. Obturation methods compared were endodontic pressure syringe, insulin syringe, jiffy tube, and local anesthetic syringe. The root canal obturations were evaluated by conventional radiography for the length of obturation and presence of voids. The obtained data were analyzed using Chi-square test. Results: The results showed significant differences between the four groups for the length of obturation (P < 0.05). The endodontic pressure syringe showed the best results (98.5% optimal fillings) and jiffy tube showed the poor results (37.5% optimal fillings) for the length of obturation. The insulin syringe (79.2% optimal fillings) and local anesthetic syringe (66.7% optimal fillings) showed acceptable results for the length of root canal obturation. However, minor voids were present in all the four techniques used. Conclusions: Endodontic pressure syringe produced the best results in terms of length of obturation and controlling paste extrusion from the apical foramen. However, insulin syringe and local anesthetic syringe can be used as effective alternative methods. PMID:27433062

  15. 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.

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

    PubMed Central

    2013-01-01

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

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

    PubMed

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

    2013-08-01

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

  18. 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…

  19. Correlates of syringe coverage for heroin injection in 35 large metropolitan areas in the US in which heroin is the dominant injected drug

    PubMed Central

    Tempalski, Barbara; Cooper, Hannah L.; Friedman, Samuel R.; Des Jarlais, Don C.; Brady, Joanne; Gostnell, Karla

    2009-01-01

    Background Scientific consensus holds that if, at the outset of the HIV/AIDS epidemic, injection drug users (IDUs) had had better access to sterile syringes, much of the epidemic among IDUs in the U.S. could have been prevented. In the context of preventing infectious diseases, 100% syringe coverage—that is, one sterile syringe per injector for each injection—is a public health goal. Notably, we know little about variations in syringe coverage within the U.S. and elsewhere, or about the social and political factors that might determine this coverage. Methods Using data from Holmberg (AJPH, 1996), the 1990 United States Census, the 2000 Beth Israel National Syringe Exchange Survey (n=72), and estimates of IDUs in metropolitan areas (MSAs); (Friedman et al., 2004), we explore the impact of (1) political factors (ACT UP, outreach, early syringe exchange programme (SEP) presence, men who have sex with men (MSM) per capita, drug arrests, and police per capita); (2) local resources for SEPs; and (3) indicators of socioeconomic inequality on SEP coverage. We define “syringe coverage” as the ratio of syringes distributed at SEPs to the number of syringes heroin injectors need in a year. We calculated the number of syringes heroin injectors need in a year by multiplying an estimate of the number of IDUs in each MSA by an estimate of the average number of times heroin injectors inject heroin per year (2.8 times per day times 365 days). In this analysis, the sample was limited to 35 MSAs in which the primary drug of choice among injectors was heroin. Results SEP coverage varies greatly across MSAs, with an average of 3 syringes distributed per 100 injection events (std dev = 0.045; range: 2 syringes per 10 injection events, to 3 syringes per 10,000 injection events). In bivariate regression analyses, a 1 unit difference in the proportion of the population that was MSM per 1,000 was associated with a difference of 0.002 in SEP coverage (p=0.052); early SEP presence was

  20. 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.

  1. Could low dead-space syringes really reduce HIV transmission to low levels?

    PubMed

    Vickerman, P; Martin, N K; Hickman, M

    2013-01-01

    Studies published by Zule and colleagues have suggested that use of low dead-space syringes (LDSS) instead of high dead-space syringes (HDSS) by injecting drug users (IDUs) could dramatically reduce HIV transmission. However, evidence is limited because experiments have considered a small range of syringe types and have been unable to reliably estimate the efficacy of using LDSS for reducing HIV transmission. We critically appraise available evidence to determine whether using LDSS is likely to dramatically reduce HIV transmission. We systematically review the literature on the dead-space volume of syringes and estimate the factor difference in blood volume transferred from sharing LDSS or HDSS. Existing data on the relationship between host viral load and HIV transmission risk is used to evaluate the likely efficacy of using LDSS instead of HDSS. An HIV transmission model is used to make conservative impact projections for switching to using LDSS, and explore the implications of heterogeneity in IDU transmission risk and syringe preferences. Although highly variable, reviewed studies suggest that HDSS have on average 10 times the dead-space volume of LDSS and could result in 6/54/489 times more blood being transferred after 0/1/2 water rinses. Assuming a conservative 2-fold increase in HIV transmission risk per 10-fold increase in infected blood inoculum, HDSS use could be associated with a mean 1.7/3.6/6.5-fold increase in transmission risk compared to LDSS for 0/1/2 rinses. However, even for a low efficacy estimate, modelling suggests that partially transferring to LDSS use from using HDSS could dramatically reduce HIV prevalence (generally >33% if LDSS use is 50%), but impact will depend on IDU behavioural heterogeneity and syringe preference. Indirect evidence suggests that encouraging HDSS users to use LDSS could be a powerful HIV prevention strategy. There is an urgent need to evaluate the real life effectiveness of this strategy. PMID:23206493

  2. Calibration of the Multi-Factor HJM Model for Energy Market

    NASA Astrophysics Data System (ADS)

    Broszkiewicz-Suwaj, E.; Weron, A.

    2006-05-01

    The purpose of this paper is to show that using the toolkit of interest rate theory, already well known in financial engineering as the HJM model [D. Heath, R. Jarrow, A. Morton, {ITALIC Econometrica} 60, 77 (1992)], it is possible to derive explicite option pricing formula and calibrate the theoretical model to the empirical electricity market. The analysis is illustrated by numerical cases from the European Energy Exchange (EEX) in Leipzig. The multi-factor {ITALIC versus} one-factor HJM models are compared.

  3. 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…

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

    SciTech Connect

    Bharanidharan, Ganesan; Manigandan, Durai; Devan, Krishnamurthy; Subramani, Vellaiyan; Gopishankar, Natanasabapathi; Ganesh, Tharmar; Joshi, Rakeshchander; Rath, Gourakishore; Velmurugan, Jagadeesan; Aruna, Prakasarao; Ganesan, Singaravelu . E-mail: sganesan@annauniv.edu

    2005-01-01

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

  5. 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.

  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. Use of SoloShot autodestruct syringes compared with disposable syringes, in a national immunization campaign in Indonesia.

    PubMed Central

    Nelson, C. M.; Sutanto, A.; Suradana, I. G.

    1999-01-01

    Autodestruct syringes can reduce the improper reuse of syringes, which present a significant risk in the transmission of bloodborne pathogens in developing countries, especially during immunization campaigns owing to the high number of injections given per session. SoloShot is an autodestruct syringe, distributed by UNICEF, which has been shown to be safer and easier to use than standard syringes. This study analyses the accuracy and dose-efficiency of SoloShot, compared with disposable syringes, during a national tetanus toxoid immunization campaign on the Indonesian island of Lombok. Observation and dose measurements revealed that SoloShot syringes delivered more precise and consistent doses and 15% more doses per vial than disposable syringes. Vaccine savings may partially be offset by the higher price of SoloShot. Vaccinators preferred SoloShot, describing it as easier to use, faster, and more accurate than the disposable syringe. The study indicates that SoloShot is highly appropriate for use in immunization campaigns by reducing vaccine wastage and improving injection safety. PMID:10063658

  8. 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

  9. 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

  10. 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

  11. Radiance factor calibration of near-infrared spectral images of Mars

    NASA Astrophysics Data System (ADS)

    Klassen, David R.; Bell, James F.

    2003-05-01

    We present radiometrically calibrated spectrophotometric images of Mars taken at the NASA Infrared Telescope Facility (IRTF) near and during the 1995 and 1999 oppositions. Absolute intensity and radiance factor ( r F = I/F) values have been calculated for approximately 95% of the surface over all longitudes between -70° to 90° latitude in the 1.5- to 4.1-μm spectral region at a spectral resolution (Δλ/λ) of 1.5%. Values of radiance factor range from r F = 0.4 to 0.6 at 2.2 μm for the bright regions such as Moab and Arabia to r F = 0.12 to 0.3 at 2.2 μm around the dark regions Syrtis Major and Acidalia Planitia. Variations are seen due to seasonal dust and/or condensate cloud cover and viewing geometry. Our results are generally consistent with the few reported previous radiance factor determinations for Mars. These data are unique among ground-based data in their relatively high spatial resolution (≲200 km/pixel at the sub-Earth point) and coverage combined with their spectral resolution and coverage. These radiometrically calibrated observations can be used as input to studies focusing on spectral unmixing of surface and atmospheric components, radiative transfer modeling of disk and limb radiances, and photometric modeling of the martian phase function.

  12. 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

  13. Storage stability of bevacizumab in polycarbonate and polypropylene syringes

    PubMed Central

    Khalili, H; Sharma, G; Froome, A; Khaw, P T; Brocchini, S

    2015-01-01

    Purpose To compare and examine the storage stability of compounded bevacizumab in polycarbonate (PC) and polypropylene (PP) syringes over a 6-month period. PC syringes have been used in a recent clinical study and bevacizumab stability has not been reported for this type of syringe. Methods Repackaged bevacizumab was obtained from Moorfields Pharmaceuticals in PC and PP syringes. Bevacizumab from the stored syringes was analysed at monthly time points for a 6-month period and compared with bevacizumab from a freshly opened vial at each time point. SDS-PAGE electrophoresis and size-exclusion chromatography (SEC) was used to observe aggregation and degradation. Dynamic light scattering (DLS) provided information about the hydrodynamic size and particle size distribution of bevacizumab in solution. VEGF binding and the active concentration of bevacizumab was determined by surface plasmon resonance (SPR) using Biacore. Results SDS-PAGE and SEC analysis did not show any changes in the presence of higher molecular weight species (HMWS) or degradation products in PC and PP syringes from T0 to T6 compared with bevacizumab sampled from a freshly opened vial. The hydrodynamic diameter of bevacizumab in the PC syringe after 6 months of storage was not significantly different to bevacizumab taken from a freshly opened vial. Using SPR, the VEGF binding activity of bevacizumab in the PC syringe was comparable to bevacizumab taken from a freshly opened vial. Conclusion No significant difference over a 6-month period was observed in the quality of bevacizumab repackaged into prefilled polycarbonate and polypropylene syringes when compared with bevacizumab that is supplied from the vial. PMID:25853399

  14. Syringe Stockpiling by Persons Who Inject Drugs: An Evaluation of Current Measures for Needle and Syringe Program Coverage.

    PubMed

    McCormack, Angus R; Aitken, Campbell K; Burns, Lucinda A; Cogger, Shelley; Dietze, Paul M

    2016-05-01

    Needle and syringe program (NSP) coverage is commonly used to assess NSP effectiveness. However, existing measures don't capture whether persons who inject drugs (PWIDs) stockpile syringes, an important and novel aspect of NSP coverage. In this study, we determine the extent of stockpiling in a sample of Australian PWIDs and assess whether including stockpiling enhances NSP coverage measures. As part of the Illicit Drug Reporting System study, PWIDs reported syringes procured and given away, total injections in the last month, and syringes currently stockpiled in 2014. We calculated NSP coverage with and without stockpiling to determine proportional change in adequate NSP coverage. We conducted receiver operating characteristic curve analysis to determine whether inclusion of stockpiled syringes in the measure improved sensitivity in discriminating cases and noncases of risky behaviors. Three-quarters of the sample reported syringe stockpiling, and stockpiling was positively associated with nonindigenous background, stable accommodation, no prison history, longer injecting careers, and more frequent injecting. Compared with previous measures, our measure was significantly better at discriminating cases of risky behaviors. Our results could inform NSP policy to loosen restricted-exchange practice, allowing PWIDs greater flexibility in syringe procurement practices, promoting greater NSP coverage, and reducing PWIDs' engagement in risky behaviors. PMID:27049004

  15. Role of syringeal vibrations in bird vocalizations

    PubMed Central

    Larsen, O. N.; Goller, F.

    1999-01-01

    The sound-generating mechanism in the bird syrinx has been the subject of debate. Recent endoscopic imaging of the syrinx during phonation provided evidence for vibrations of membranes and labia, but could not provide quantitative analysis of the vibrations. We have now recorded vibrations in the intact syrinx directly with an optic vibration detector together with the emitted sound during brain stimulation-induced phonation in anaesthetized pigeons, cockatiels, and a hill myna. The phonating syrinx was also filmed through an endoscope inserted into the trachea. In these species vibrations were always present during phonation, and their frequency and amplitude characteristics were highly similar to those of the emitted sound, including nonlinear acoustic phenomena. This was also true for tonal vocalizations, suggesting that a vibratory mechanism can account for all vocalizations presented in the study. In some vocalizations we found differences in the shape of the waveform between vibrations and the emitted sound, probably reflecting variations in oscillatory behaviour of syringeal structures. This study therefore provides the first direct evidence for a vibratory sound-generating mechanism (i.e. lateral tympaniform membranes or labia acting as pneumatic valves) and does not support pure aerodynamic models. Furthermore, the data emphasize a potentially high degree of acoustic complexity.

  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 μm to 0.2 μm and velocities between 19 and 37.9 km s-1, impacting on a Rh-target.

  17. Non-prescription syringe sales in California: a qualitative examination of practices among 12 local health jurisdictions.

    PubMed

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

    2010-07-01

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

  18. 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

  19. The association between law enforcement encounters and syringe sharing among IDUs on skid row: a mixed methods analysis.

    PubMed

    Wagner, Karla D; Simon-Freeman, Rebecca; Bluthenthal, Ricky N

    2013-10-01

    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

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

    PubMed Central

    2007-01-01

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

  1. Syringe disposal among injection drug users in Harlem and the Bronx during the New York State Expanded Syringe Access Demonstration Program.

    PubMed

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

    2007-04-01

    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 the last injection episode were combined from three projects (N = 1,030) recruiting injection drug users. Disposal of syringes by methods known to be safe decreased significantly over time after the implementation of ESAP. Syringes obtained either from syringe exchange programs or ESAP sources were more likely to be disposed of safely than syringes obtained from other sources. Efforts to enlist pharmacists and others involved in ESAP implementation to encourage safe disposal are needed. More detailed information on disposal practices is needed to capture the continuum from least to most safe practices and variation within individuals. PMID:16816027

  2. DETECTION OF ENDOGENOUS TISSUE FACTOR LEVELS IN PLASMA USING THE CALIBRATED AUTOMATED THROMBOGRAM ASSAY

    PubMed Central

    Ollivier, Veronique; Wang, Jianguo; Manly, David; Machlus, Kellie R.; Wolberg, Alisa S.; Jandrot-Perrus, Martine; Mackman, Nigel

    2009-01-01

    Summary Background The calibrated automated thrombogram (CAT) assay measures thrombin generation in plasma. Objective Use the CAT assay to detect endogenous tissue factor (TF) in recalcified platelet-rich plasma (PRP) and platelet-free plasma (PFP). Methods Blood from healthy volunteers was collected into citrate and incubated at 37°C with or without lipopolysaccharide (LPS) for 5 hours. PRP and PFP were prepared and clotting was initiated by recalcification. Thrombin generation was measured using the CAT assay. Results The lag time (LT) was significantly shortened in PRP prepared from LPS-treated blood compared with untreated blood (10 ± 3 min versus 20 ± 6 min), and this change was reversed by the addition of inactivated human factor VIIa. LPS stimulation did not change the peak thrombin. Similar results were observed in PFP (21 ± 4 min versus 35 ± 5 min). LPS stimulation also significantly reduced the LT of PRP and PFP derived from blood containing citrate and a factor XIIa inhibitor. Finally, a low concentration of exogenous TF shortened the LT of PFP prepared from unstimulated, citrated blood without affecting the peak thrombin. Conclusion Changes in LT in the CAT assay can be used to monitor levels of endogenous TF in citrated plasma. PMID:19345399

  3. Observational calibration of the projection factor of Cepheids. I. The type II Cepheid κ 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 κ Pavonis. Methods: The parallax of the type-II Cepheid κ 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 κ 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 κ 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

  4. 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

  5. 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

  6. 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.

  7. In-flight calibration of NOAA POES proton detectors—Derivation of the MEPED correction factors

    NASA Astrophysics Data System (ADS)

    Sandanger, Marit Irene; Ødegaard, Linn-Kristine Glesnes; Nesse Tyssøy, Hilde; Stadsnes, Johan; Søraas, Finn; Oksavik, Kjellmar; Aarsnes, Kjell

    2015-11-01

    The MEPED instruments on board the NOAA POES and MetOp satellites have been continuously measuring energetic particles in the magnetosphere since 1978. However, degradation of the proton detectors over time leads to an increase in the energy thresholds of the instrument and imposes great challenges to studies of long-term variability in the near-Earth space environment as well as a general quantification of the proton fluxes. By comparing monthly mean accumulated integral flux from a new and an old satellite at the same magnetic local time (MLT) and time period, we estimate the change in energy thresholds. The first 12 monthly energy spectra of the new satellite are used as a reference, and the derived monthly correction factors over a year for an old satellite show a small spread, indicating a robust calibration procedure. The method enables us to determine for the first time the correction factors also for the highest-energy channels of the proton detector. In addition, we make use of the newest satellite in orbit (MetOp-01) to find correction factors for 2013 for the NOAA 17 and MetOp-02 satellites. Without taking into account the level of degradation, the proton data from one satellite cannot be used quantitatively for more than 2 to 3 years after launch. As the electron detectors are vulnerable to contamination from energetic protons, the corrected proton measurements will be of value for electron flux measurements too. Thus, the correction factors ensure the correctness of both the proton and electron measurements.

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

    PubMed Central

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

    1999-01-01

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

  9. Supermarket tampering: cocaine detected in syringes and in fruit.

    PubMed

    Tomlinson, J A; Crowe, J B; Ranieri, N; Kindig, J P; Platek, S F

    2001-01-01

    Product tampering, as detailed by the Federal Anti-Tampering Act of 1983 (1), is a felony punishable by both fine and imprisonment. The rationale for product tampering ranges from pranks and attention seeking acts to extortion, terrorism, and homicide. One such case submitted for analysis involved four medical syringes found in a supermarket and suspected of being used to tamper with various products. One of the syringes was found piercing a pear while the other three syringes were found with needles exposed in other parts of the supermarket. Microscopic analysis was used to collect residue from the syringe barrels and the pear. A multidiscipline approach involving SLM, PLM, including microchemical analysis, FTIR, and GC/MS analyses, performed on the residual liquid found in the syringe barrels and in the suspect pear, confirmed the presence of cocaine. This multidisciplinary approach is often necessary when there is a possible health risk to the public and rapid response is important. With this approach, it was quickly determined which drugs or poisons were used in this tampering. PMID:11210900

  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-μ-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-μ-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. Weighted calibration with reduced number of signals by weighing factor modelling: application to the identification of explosives by ion chromatography.

    PubMed

    Brasil, Beatriz; Bettencourt da Silva, Ricardo J N; Camões, M Filomena G F C; Salgueiro, Pedro A S

    2013-12-01

    The linear weighted regression model (LW) can be used to calibrate analytical instrumentation in a range of quantities (e.g. concentration or mass) wider than possible by the linear unweighted regression model, LuW (i.e. the least squares regression model), since this model can be applied when signals are not equally precise through the calibration range. If precision of signals varies within the calibration range, the regression line should be defined taking into account that more precise signals are more reliable and should count more to define regression parameters. Nevertheless, the LW requires the determination of the variation of signals precision through the calibration range. Typically, this information is collected experimentally for each calibration, requiring a large number of replicate collection of signals of calibrators. This work proposes reducing the number of signals needed to perform LW calibrations by developing models of weighing factors robust to daily variations of instrument sensibility. These models were applied to the determination of the ionic composition of the water soluble fraction of explosives. The adequacy of the developed models was tested through the analysis of control standards, certified reference materials and the ion balance of anions and cations in aqueous extracts of explosives, considering the measurement uncertainty estimated by detailed metrological models. The high success rate of the comparisons between estimated and known quantity values of reference solutions, considering results uncertainty, proves the validity of developed metrological models. The relative expanded measurement uncertainty of single determinations ranged from 1.93% to 35.7% for calibrations performed along 4 months. PMID:24267095

  12. Not sold here: limited access to legally available syringes at pharmacies in Tijuana, Mexico

    PubMed Central

    2011-01-01

    Background Sterile syringe access is a critical component of HIV prevention programs. Although retail pharmacies provide convenient outlets for syringe access, injection drug users (IDUs) may encounter barriers to syringe purchase even where purchase without a prescription is legal. We sought to obtain an objective measure of syringe access in Tijuana, Mexico, where IDUs report being denied or overcharged for syringes at pharmacies. Methods Trained "mystery shoppers" attempted to buy a 1 cc insulin syringe according to a predetermined script at all retail pharmacies in three Tijuana neighborhoods. The same pharmacies were surveyed by telephone regarding their syringe sales policies. Data on purchase attempts were analyzed using basic statistics to obtain an objective measure of syringe access and compared with data on stated sales policies to ascertain consistency. Results Only 46 (28.4%) of 162 syringe purchase attempts were successful. Leading reasons for unsuccessful attempts were being told that the pharmacy didn't sell syringes (35.3%), there were no syringes in stock (31.0%), or a prescription was required (20.7%). Of 136 pharmacies also surveyed by telephone, a majority (88.2%) reported selling syringes but only one-third (32.5%) had a successful mystery shopper purchase; the majority of unsuccessful purchases were attributed to being told the pharmacy didn't sell syringes. There was similar discordance regarding prescription policies: 74 pharmacies said in the telephone survey that they did not require a prescription for syringes, yet 10 of these pharmacies asked the mystery shopper for a prescription. Conclusions IDUs in Tijuana have limited access to syringes through retail pharmacies and policies and practices regarding syringe sales are inconsistent. Reasons for these restrictive and inconsistent practices must be identified and addressed to expand syringe access, reduce syringe sharing and prevent HIV transmission. PMID:21609471

  13. 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

  14. The rate of sulfur hexafluoride escape from a plastic syringe.

    PubMed

    Humayun, M S; Yeo, J H; Koski, W S; Michels, R G

    1989-06-01

    Sulfur hexafluoride (SF6) gas is widely used for internal tamponade during retinal reattachment surgery and is commonly injected into the eye from a 10-mL plastic syringe. The rate of diffusion of SF6 out of a plastic syringe has not bee studied. We measured the percentage of SF6 gas in a 10-mL plastic syringe by gas chromatography, confirmed by infrared spectrometry. Measurements were obtained immediately after aspiration, and at 30 s and 10, 15, 60, 90, and 120 minutes, and 18 hours. A marked decrease in SF6 concentration, from 97% at 30 s to 76% at 60 minutes and 2% at 18 hours, was noted. The results were highly reproducible. Sulfur hexafluoride gas should be injected into the patient's eye as soon as possible after aspiration from the tank to ensure accurate concentrations. PMID:2730405

  15. Clean switch: the case for prison needle and syringe programs.

    PubMed

    Chu, Sandra

    2009-12-01

    In Canada and in many other countries, prisons have become incubators for the transmission of HIV and hepatitis C virus (HCV). Estimates of HIV and HCV prevalence in Canadian prisons are at least 10 and 20 times, respectively, the reported prevalence in the population as a whole--and prevalence rates have been reported to be significantly higher for people who inject drugs. Although people who inject drugs may inject less frequently while incarcerated, the risks of injection drug use are amplified because of the scarcity of sterile syringes and the sharing of injecting equipment in prison. Making sterile injection equipment available to people in prison is an important response to evidence of the risk of HIV and HCV transmission through sharing syringes to inject drugs. In this article, Sandra Chu explains why the government is obligated under international human rights standards and Canadian correctional and constitutional law to provide prison-based needle and syringe programs (PNSPs). PMID:20225504

  16. 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.

  17. Liquid Drugs and High Dead Space Syringes May Keep HIV and HCV Prevalence High – A Comparison of Hungary and Lithuania

    PubMed Central

    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

  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

  19. A clinical comparison of pain perception and extent of area anesthetized by Wand® and a traditional syringe

    PubMed Central

    Shah, Meet; Shivaswamy, Sumanth; Jain, Sanjay; Tambwekar, Sonal

    2012-01-01

    Background: In the contemporary dental practice, alleviation of pain is the most important factor to ameliorate patient's condition and to gain one's confidence towards the skills of the operator. Such confidence aids to the ultimate success of the treatment procedures. Aims and Objectives: This study compares the pain response of a group of 10 subjects to the Wand® with the response to traditional syringe injections and also compares the extent of the area anesthetized. Materials and Methods: 10 subjects were selected for the study and 20 injections were given contralaterally to them, 10 with Wand®, and rest with the traditional aspirating syringe. Each subject received 2 injections on the palate, Left side with Wand® (test) and Right side with Traditional syringe (control). All injections were given by the same investigator without the use of topical anesthetic spray/gel. Pain perception levels were recorded with a visual analogue scale. Also the extent of area anesthetized with a single palatal injection was assessed by probing. Results: The results showed injections with the syringe were more painful than injections with the Wand® in 2 of 10 subjects. Also the extent of the area anesthetized by both the techniques was similar except in 2 patients. Conclusion: The Wand® results in less painful injections; however, mean ratings of pain for both the groups, were mostly below the annoying level of pain. Also, the areas covered by the anesthetic effect of both the injections were comparatively similar. PMID:23055586

  20. Treatment of inverted nipples using a disposable syringe.

    PubMed

    Kesaree, N; Banapurmath, C R; Banapurmath, S; Shamanur, K

    1993-03-01

    Seven mothers who had inverted nipples were helped to breastfeed their infants with the assistance of a simple device made from a 10 ml disposable syringe. These women were able to successfully breastfeed within one week. On follow-up, these mothers were able to sustain adequate breastfeeding. PMID:8489719

  1. 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... that uses a spring-loaded mechanism to drive a hypodermic needle into a patient to a...

  2. 21 CFR 880.6920 - Syringe needle introducer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Syringe needle introducer. 880.6920 Section 880.6920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... that uses a spring-loaded mechanism to drive a hypodermic needle into a patient to a...

  3. 21 CFR 880.6920 - Syringe needle introducer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Syringe needle introducer. 880.6920 Section 880.6920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... that uses a spring-loaded mechanism to drive a hypodermic needle into a patient to a...

  4. 21 CFR 880.6920 - Syringe needle introducer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Syringe needle introducer. 880.6920 Section 880.6920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... that uses a spring-loaded mechanism to drive a hypodermic needle into a patient to a...

  5. 21 CFR 880.6920 - Syringe needle introducer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Syringe needle introducer. 880.6920 Section 880.6920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... that uses a spring-loaded mechanism to drive a hypodermic needle into a patient to a...

  6. 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…

  7. 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

  8. 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.

  9. Disinfection of syringes contaminated with hepatitis C virus by rinsing with household products.

    PubMed

    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

  10. Modeling and Calibration for Exposure to Time-Varying, Modifiable Risk Factors: The Example of Smoking Behavior in India

    PubMed Central

    Goldhaber-Fiebert, Jeremy D.; Brandeau, Margaret L.

    2014-01-01

    Background Risk factors increase chronic disease incidence and severity. To examine future trends and develop policies addressing chronic diseases, it is important to capture the relationship between exposure and disease development -- challenging given limited data. Objective To develop parsimonious risk factor models embeddable in chronic disease models, useful when longitudinal data are unavailable. Design The model structures encode relevant features of risk factors (e.g., time-varying, modifiable) and can be embedded in chronic disease models. Calibration captures time-varying exposures for the risk factor models using available, cross-sectional data. We illustrate feasibility with the policy-relevant example of smoking in India. Methods The model is calibrated to prevalence of male smoking in 12 Indian regions estimated from the 2009–10 Indian Global Adult Tobacco Survey. Nelder-Mead searches (250,000 starting locations) identify distributions of starting, quitting, and re-starting rates that minimize the difference between modeled and observed age-specific prevalence. We compare modeled life expectancies to estimates in the absence of time-varying risk exposures and consider gains from hypothetical smoking cessation programs delivered for 1–30 years. Results Calibration achieves concordance between modeled and observed outcomes. Probabilities of starting to smoke rise and fall with age, while quitting and re-starting probabilities fall with age. Accounting for time-varying smoking exposures is important, as not doing so produces smaller estimates of life expectancy losses. Estimated impacts of smoking cessation programs delivered for different periods depend on the fact that people who have been induced to abstain from smoking longer are less likely to re-start. Conclusion The approach described is feasible for numerous chronic disease risk factors. Incorporating exposure-change rates can improve modeled estimates of chronic disease outcomes and long

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

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

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

  12. Stability of ondansetron hydrochloride and 12 medications in plastic syringes.

    PubMed

    Stewart, J T; Warren, F W; King, D T; Venkateshwaran, T G; Fox, J L

    1998-12-15

    The stability and compatibility of ondansetron hydrochloride with neostigmine methylsulfate, naloxone hydrochloride, midazolam hydrochloride, fentanyl citrate, alfentanil hydrochloride, atropine sulfate, morphine sulfate, meperidine hydrochloride, propofol, droperidol, metoclopramide monohydrochloride, and glycopyrrolate were studied. Ondansetron 1.33 or 1.0 mg/mL was combined with 0.9% sodium chloride injection and each of the 12 drugs in duplicate in plastic syringes (or glass for propofol). The syringes were stored at 21.8-23.4 or 4 degrees C in the dark, except for those containing propofol, which were stored at ambient temperature. Samples were removed at 0, 4, 8, and 24 hours for analysis by high-performance liquid chromatography and pH measurement; the propofol-containing samples were removed at 0, 1, 2, and 4 hours. Syringes were visually assessed for color and clarity, and particulate content was measured with a particle counter at the end of the study period. All solutions containing ondansetron retained more than 90% of their initial ondansetron concentration. Solutions containing each of the other drugs except droperidol retained more than 90% of their initial concentration of these drugs. The solutions containing droperidol retained more than 90% of their initial droperidol concentration for up to eight hours at ambient temperature but precipitated quickly at 4 degrees C. In combinations of ondansetron 1.33 or 1.0 mg/mL and 10 of 12 drugs, all drugs were stable for 24 hours in plastic syringes at 23 and 4 degrees C; ondansetron hydrochloride 1.0 mg/mL and propofol 1.0 and 5.0 mg/mL in admixtures were stable for 4 hours, and droperidol on its own and combined with ondansetron 1.0 mg/mL was stable for no more than 8 hours at ambient temperature. PMID:9872702

  13. Note: On the wavelength dependence of the intensity calibration factor of extreme ultraviolet spectrometer determined with profile measurement of bremsstrahlung continuum

    SciTech Connect

    Yamaguchi, N.; Morita, S.; Dong, C. F.; Goto, M.; Maezawa, H.; Miyauchi, H.

    2015-06-15

    The absolute calibration factor of extreme ultraviolet spectroscopic instrument which has recently been determined from absolute radiation profile measurement of bremsstrahlung continuum has been investigated by comparing the calculated diffraction efficiency of grating. An overall tendency of the wavelength dependence of the calibration factor from 40 Å to 500 Å can be reproduced by that of the grating efficiency, especially the agreement between the measured calibration factor and the calculated grating efficiency has been found to be fairly good for the wavelength range 200 Å-500 Å.

  14. Correlates of lending needles/syringes among HIV-seropositive injection drug users.

    PubMed

    Metsch, Lisa R; Pereyra, Margaret; Purcell, David W; Latkin, Carl A; Malow, Robert; Gómez, Cynthia A; Latka, Mary H

    2007-11-01

    Among HIV-positive injection drug users (IDUs), we examined the correlates of lending needles/syringes with HIV-negative and unknown status injection partners. HIV-positive IDUs (N=738) from 4 cities in the United States who reported injection drug use with other IDUs in the past 3 months participated in an audio computer-assisted self-administered interview. Eighteen percent of study participants self-reported having lent their needles to HIV-negative or unknown status injection partners. Multivariate analyses showed that 6 variables were significantly associated with this high-risk injecting practice. Older IDUs, high school graduates, and those reporting more supportive peer norms for safer drug use were less likely to lend needles/syringes. Admission to a hospital for drug treatment in the past 6 months, having injected with >1 person in the past 3 months, and having more psychiatric symptoms were all associated with more risk. These findings underscore the need for a continued prevention focus on HIV-positive IDUs that recognizes the combination of drug use, mental health factors, and social factors that might affect this high-risk injecting practice, which could be associated with HIV and hepatitis C transmission. PMID:18089987

  15. 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

  16. 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

  17. Consequences of a restrictive syringe exchange policy on utilization patterns of a syringe exchange program in Baltimore, Maryland: Implications for HIV risk

    PubMed Central

    Sherman, Susan G.; Patel, Shivani A.; Ramachandran, Daesha V.; Galai, Noya; Chaulk, Patrick; Serio-Chapman, Chris; Gindi, Renee M.

    2016-01-01

    Background Syringe distribution policies continue to be debated in many jurisdictions throughout the U.S. The Baltimore Needle and Syringe Exchange Program (NSP) operated under a 1-for-1 syringe exchange policy from its inception in 1994 through 1999, when it implemented a restrictive policy (2000–2004) that dictated less than 1-for-1 exchange for non-program syringes. Methods Data were derived from the Baltimore NSP, which prospectively collected data on all client visits. We examined the impact of this restrictive policy on program-level output measures (i.e., distributed:returned syringe ratio, client volume) before, during, and after the restrictive exchange policy. Through multiple logistic regression, we examined correlates of less than 1-for-1 exchange ratios at the client-level before and during the restrictive exchange policy periods. Results During the restrictive policy period, the average annual program-level ratio of total syringes distributed:returned dropped from 0.99 to 0.88, with a low point of 0.85 in 2000. There were substantial decreases in the average number of syringes distributed, syringes returned, the total number of clients, and new clients enrolling during the restrictive compared to the preceding period. During the restrictive period, 33,508 more syringes were returned to the needle exchange than were distributed. In the presence of other variables, correlates of less than 1-for-1 exchange ratio were being white, female, and less than 30 years old. Discussion With fewer clean syringes in circulation, restrictive policies could increase the risk of exposure to HIV among IDUs and the broader community. The study provides evidence to the potentially harmful effects of such policies. PMID:25919590

  18. Prevalence and Correlates of the Use of Prefilled Syringes Among Persons Who Inject Drugs in San Diego, CA.

    PubMed

    Armenta, Richard F; Roth, Alexis M; Wagner, Karla D; Strathdee, Steffanie A; Brodine, Stephanie K; Cuevas-Mota, Jazmine; Munoz, Fatima A; Garfein, Richard S

    2015-12-01

    Persons who inject drugs (PWID) are at increased risk for blood-borne virus (BBV) infections and overdose resulting from high-risk injecting practices. Studies of prefilled syringe use ([PFSU] using a syringe that already contained drug solution when it was obtained by the user), an injection practice previously described in Eastern Europe, suggest that it increases susceptibility to BBV. However, little is known about this practice in the USA. Data were obtained from an ongoing cohort study of PWID to determine the prevalence and assess correlates of PFSU in San Diego, CA. Baseline interviews assessed socio-demographics and drug use behaviors. Logistic regression was used to identify factors independently associated with ever using a prefilled syringe (yes/no). Participants (n = 574) were predominately males (73.9%) and white (50.9%) with a mean age of 43.4 years (range 18-80); 33.3% reported ever using prefilled syringes, although only 4.9% reported use in the past 6 months. In multivariable analyses, PFSU was independently associated with ever having a rushed injection due to police presence [adjusted odds ratio (AOR) = 2.51, 95% CI 1.66, 3.79], ever being in prison (AOR = 1.80, 95% CI 1.23, 2.63), injecting most often in public versus private places in the past 6 months (AOR = 1.66, 95% CI 1.11, 2.48), and injecting drugs in Mexico (AOR = 1.70, 95% CI 1.16, 2.49). Results indicate that a history of PFSU is common and associated with environmental factors that may also increase risk for adverse health outcomes. Studies are needed to better understand PFSU in order to develop interventions to prevent adverse outcomes associated with their use. PMID:26382653

  19. Greater Drug Injecting Risk for HIV, HBV, and HCV Infection in a City Where Syringe Exchange and Pharmacy Syringe Distribution are Illegal

    PubMed Central

    Zhao, Mingfang; Gyarmathy, V. Anna; Cisek, Linda; Friedman, Samuel R.; Baxter, Robert C.

    2008-01-01

    Comparing drug-injecting risk between cities that differ in the legality of sterile syringe distribution for injection drug use provides a natural experiment to assess the efficacy of legalizing sterile syringe distribution as a structural intervention to prevent human immunodeficiency virus (HIV) and other parenterally transmitted infections among injection drug users (IDUs). This study compares the parenteral risk for HIV and hepatitis B (HBV) and C (HCV) infection among IDUs in Newark, NJ, USA, where syringe distribution programs were illegal during the period when data were collected, and New York City (NYC) where they were legal. IDUs were nontreatment recruited, 2004–2006, serotested, and interviewed about syringe sources and injecting risk behaviors (prior 30 days). In multivariate logistic regression, adjusted odds ratios (AOR) and 95% confidence intervals (95% CI) for city differences are estimated controlling for potential city confounders. IDUs in Newark (n = 214) vs. NYC (n = 312) were more likely to test seropositive for HIV (26% vs. 5%; AOR = 3.2; 95% CI = 1.6, 6.1), antibody to the HBV core antigen (70% vs. 27%; AOR = 4.4; 95% CI = 2.8, 6.9), and antibody to HCV (82% vs. 53%; AOR = 3.0; 95% CI = 1.8, 4.9), were less likely to obtain syringes from syringe exchange programs or pharmacies (AOR = 0.004; 95% CI = 0.001, 0.01), and were more likely to obtain syringes from street sellers (AOR = 74.0; 95% CI = 29.9, 183.2), to inject with another IDU’s used syringe (AOR = 2.3; 95% CI = 1.1, 5.0), to reuse syringes (AOR = 2.99; 95% CI = 1.63, 5.50), and to not always inject once only with a new, sterile syringe that had been sealed in a wrapper (AOR = 5.4; 95% CI = 2.9, 10.3). In localities where sterile syringe distribution is illegal, IDUs are more likely to obtain syringes from unsafe sources and to engage in injecting risk behaviors. Legalizing and rapidly implementing sterile

  20. 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

  1. Polypyrrole/polyamide electrospun-based sorbent for microextraction in packed syringe of organophosphorous pesticides from aquatic samples.

    PubMed

    Bagheri, Habib; Ayazi, Zahra; Aghakhani, Ali; Alipour, Noshin

    2012-01-01

    A novel method based on microextraction in packed syringe (MEPS) as sample preparation technique coupled off-line with gas chromatography-mass spectrometry was developed using electrospun nanofibers as sorbent. For electrospinning of polypyrrole/polyamide-based nanofiber, a homogeneous solution containing nylon 6, ferric chloride and pyrrole monomer was prepared and then was drawn into a 2.5-mL syringe. By applying a voltage of 13 kV between the needle of the syringe and an aluminum-foil collector, the nanofibers could be formed on the surface of the collector. The prepared sheet was used as the sorbent for MEPS to analyze some selected organophosphorous pesticides. Important parameters influencing the extraction and desorption processes were optimized. Limits of detection were in the range of 0.04-0.1 ng/mL using time scheduled selected ion monitoring mode, and the relative standard deviation (RSD %) values with four replicates were in the range of 3.7-11.8% at a concentration level of 5 ng/mL. The linearity of the method was in the range of 0.5-500 ng/mL for diazinon and fenithrothion and 0.5-200 ng/mL for the rest of the analytes. The developed method was successfully applied to Zayandeh-roud river water samples, whereas the matrix factors were in the range of 0.87-0.98. PMID:22144091

  2. Long-term survey of a syringe-dispensing machine needle exchange program: answering public concerns

    PubMed Central

    2014-01-01

    Background Syringe-dispensing machines (SDM) provide syringes at any time even to hard-to-reach injecting drug users (IDUs). They represent an important harm reduction strategy in large populated urban areas such as Paris. We analyzed the performance of one of the world's largest SDM schemes based in Paris over 12 years to understand its efficiency and its limitations, to answer public and stakeholder concerns and optimize its outputs. Methods Parisian syringe dispensing and exchange machines were monitored as well as their sharp disposals and associated bins over a 12-year period. Moreover, mechanical counting devices were installed on specific syringe-dispensing/exchange machines to record the characteristics of the exchange process. Results Distribution and needle exchange have risen steadily by 202% for the distribution and 2,000% for syringe recovery even without a coin counterpart. However, 2 machines out of 34 generate 50% of the total activity of the scheme. It takes 14 s for an IDU to collect a syringe, while the average user takes 3.76 syringes per session 20 min apart. Interestingly, collection time stops early in the evening (19 h) for the entire night. Conclusions SDMs had an increasing distribution role during daytime as part of the harm reduction strategy in Paris with efficient recycling capacities of used syringes and a limited number of kits collected by IDU. Using counting devices to monitor Syringe Exchange Programs (SEPs) is a very helpful tool to optimize use and answer public and stakeholder concerns. PMID:24885902

  3. Observational calibration of the projection factor of Cepheids. II. Application to nine Cepheids with HST/FGS parallax measurements

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

    Context. The distance to pulsating stars is classically estimated using the parallax-of-pulsation (PoP) method, which combines spectroscopic radial velocity (RV) measurements and angular diameter (AD) estimates to derive the distance of the star. A particularly important application of this method is the determination of Cepheid distances in view of the calibration of their distance scale. However, the conversion of radial to pulsational velocities in the PoP method relies on a poorly calibrated parameter, the projection factor (p-factor). Aims: We aim to measure empirically the value of the p-factors of a homogeneous sample of nine bright Galactic Cepheids for which trigonometric parallaxes were measured with the Hubble Space Telescope (HST) Fine Guidance Sensor. Methods: We use the SPIPS algorithm, a robust implementation of the PoP method that combines photometry, interferometry, and radial velocity measurements in a global modeling of the pulsation of the star. We obtained new interferometric angular diameter measurements using the PIONIER instrument at the Very Large Telescope Interferometer (VLTI), completed by data from the literature. Using the known distance as an input, we derive the value of the p-factor of the nine stars of our sample and study its dependence with the pulsation period. Results: We find the following p-factors: p = 1.20 ± 0.12 for RT Aur, p = 1.48 ± 0.18 for T Vul, p = 1.14 ± 0.10 for FF Aql, p = 1.31 ± 0.19 for Y Sgr, p = 1.39 ± 0.09 for X Sgr, p = 1.35 ± 0.13 for W Sgr, p = 1.36 ± 0.08 for β Dor, p = 1.41 ± 0.10 for ζ Gem, and p = 1.23 ± 0.12 for ℓ Car. Conclusions: The values of the p-factors that we obtain are consistently close to p = 1.324 ± 0.024. We observe some dispersion around this average value, but the observed distribution is statistically consistent with a constant value of the p-factor as a function of the pulsation period (χ2 = 0.669). The error budget of our determination of the p-factor values is

  4. 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

  5. Simultaneous extraction and determination of albendazole and triclabendazole by a novel syringe to syringe dispersive liquid phase microextraction-solidified floating organic drop combined with high performance liquid chromatography.

    PubMed

    Asadi, Mohammad; Dadfarnia, Shayessteh; Haji Shabani, Ali Mohammad

    2016-08-17

    A syringe to syringe dispersive liquid phase microextraction-solidified floating organic drop was introduced and used for the simultaneous extraction of trace amounts of albendazole and triclabendazole from different matrices. The extracted analytes were determined by high performance liquid chromatography along with fluorescence detection. The analytical parameters affecting the microextraction efficiency including the nature and volume of the extraction solvent, sample volume, sample pH, ionic strength and the cycles of extraction were optimized. The calibration curves were linear in the range of 0.1-30.0 μg L(-1) and 0.2-30.0 μg L(-1) with determination coefficients of 0.9999 and 0.9998 for albendazole and triclabendazole respectively. The detection limits defined as three folds of the signal to noise ratio were found to be 0.02 μg L(-1) for albendazole and 0.06 μg L(-1) for triclabendazole. The inter-day and intra-day precision (RSD%) for both analytes at three concentration levels (0.5, 2.0 and 10.0 μg L(-1)) were in the range of 6.3-10.1% and 5.0-7.5% respectively. The developed method was successfully applied to determine albendazole and triclabendazole in water, cow milk, honey, and urine samples. PMID:27286766

  6. Effective breakage of phage lambda DNA by shearing with ceramic-coated needle of syringe.

    PubMed

    Inokuchi, Hachiro; Inokuti, Yukio

    2005-02-01

    The loss of biological activity of phage lambda DNA was much greater when the DNA was sheared using a ceramic-coated needle attached to a syringe compared with a conventional stainless steel needle. Inactivation of the biological activity was due to breakage at the middle of the molecule. The thickness of the ceramic-coating was a crucial factor for the breakage. Because approximately the same level of inactivation was observed with a non-coated needle as with thin glass and quartz tubes, it was concluded that the unknown characteristic(s) of the silicon nitride (SiNx) coating itself resulted in the effective breakage of lambda DNA molecules by shearing force. PMID:15824459

  7. [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

  8. A simple and cheap alternative to spring loaded syringe for the identification of epidural space.

    PubMed

    Malhotra, Naveen; Jangra, Anil

    2008-04-01

    A simple and cheap alternative to spring-loaded syringe for the identification of epidural space is described. It is easily assembled using a syringe and a rubber band. This assembly is reusable and is especially useful for beginners. PMID:18453501

  9. Inhibitory Activities of Alkyl Syringates and Related Compounds on Aflatoxin Production.

    PubMed

    Furukawa, Tomohiro; Iimura, Kurin; Kimura, Taichi; Yamamoto, Toshiyoshi; Sakuda, Shohei

    2016-01-01

    Inhibitors of aflatoxin production of aflatoxigenic fungi are useful for preventing aflatoxin contamination in crops. As methyl syringate weakly inhibits aflatoxin production, aflatoxin production inhibitory activities of additional alkyl syringates with alkyl chains from ethyl to octyl were examined. Inhibitory activity toward aflatoxin production of Aspergillus flavus became stronger as the length of the alkyl chains on the esters became longer. Pentyl, hexyl, heptyl, and octyl syringates showed strong activity at 0.05 mM. Heptyl and octyl parabens, and octyl gallate also inhibited aflatoxin production as strongly as octyl syringate. Alkyl parabens and alkyl gallates inhibit the complex II activity of the mitochondrial respiration chain; thus, whether alkyl syringates inhibit complex II activity was examined. Inhibitory activities of alkyl syringates toward complex II also became stronger as the length of the alkyl chains increased. The complex II inhibitory activity of octyl syringate was comparable to that of octyl paraben and octyl gallate. These results suggest that alkyl syringates, alkyl parabens, and alkyl gallates, including commonly used food additives, are useful for aflatoxin control. PMID:27338472

  10. Inhibitory Activities of Alkyl Syringates and Related Compounds on Aflatoxin Production

    PubMed Central

    Furukawa, Tomohiro; Iimura, Kurin; Kimura, Taichi; Yamamoto, Toshiyoshi; Sakuda, Shohei

    2016-01-01

    Inhibitors of aflatoxin production of aflatoxigenic fungi are useful for preventing aflatoxin contamination in crops. As methyl syringate weakly inhibits aflatoxin production, aflatoxin production inhibitory activities of additional alkyl syringates with alkyl chains from ethyl to octyl were examined. Inhibitory activity toward aflatoxin production of Aspergillus flavus became stronger as the length of the alkyl chains on the esters became longer. Pentyl, hexyl, heptyl, and octyl syringates showed strong activity at 0.05 mM. Heptyl and octyl parabens, and octyl gallate also inhibited aflatoxin production as strongly as octyl syringate. Alkyl parabens and alkyl gallates inhibit the complex II activity of the mitochondrial respiration chain; thus, whether alkyl syringates inhibit complex II activity was examined. Inhibitory activities of alkyl syringates toward complex II also became stronger as the length of the alkyl chains increased. The complex II inhibitory activity of octyl syringate was comparable to that of octyl paraben and octyl gallate. These results suggest that alkyl syringates, alkyl parabens, and alkyl gallates, including commonly used food additives, are useful for aflatoxin control. PMID:27338472

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

    PubMed

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

    2014-12-01

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

  12. 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…

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

    PubMed

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

    2010-01-01

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

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

    PubMed Central

    2010-01-01

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

  15. Leakage of Oxygen from Blood and Water Samples Stored in Plastic and Glass Syringes

    PubMed Central

    Scott, Peter V.; Horton, J. N.; Mapleson, W. W.

    1971-01-01

    Theory and experiment showed that samples of blood and water stored in 2-ml and 5-ml syringes made of polypropylene, polystyrene, or S.A.N. co-polymer exchanged oxygen with their surroundings. In the first hour the exchange was due mainly to equilibration with the plastic of the syringe and only in small degree to permeation through the plastic. With high initial tension or with blood of low haemoglobin concentration the exchange can result in errors in Po2 of up to 6% in two minutes and 16% in 30 to 60 minutes. With all-glass syringes the exchange was much slower but, even so, after 24 hours was important in all but a few of 18 interchangeable glass syringes. Therefore unless analysis can be started immediately all-glass syringes are to be preferred, and for prolonged storage even these should be selected. PMID:5565518

  16. Plausible authentication of manuka honey and related products by measuring leptosperin with methyl syringate.

    PubMed

    Kato, Yoji; Fujinaka, Rie; Ishisaka, Akari; Nitta, Yoko; Kitamoto, Noritoshi; Takimoto, Yosuke

    2014-07-01

    Manuka honey, obtained from Leptospermum scoparium flowers in New Zealand, has strong antibacterial properties. In this study, plausible authentication of the manuka honey was inspected by measuring leptosperin, methyl syringate 4-O-β-D-gentiobiose, along with methyl syringate. Despite a gradual decrease in methyl syringate content over 30 days at 50 °C, even at moderate 37 °C, leptosperin remained stable. A considerable correlation between nonperoxide antibacterial activity and leptosperin content was observed in 20 certified manuka honey samples. Leptosperin and methyl syringate in manuka honey and related products were analyzed using HPLC connected with mass spectrometry. One noncertified brand displayed significant variations in the leptosperin and methyl syringate contents between two samples obtained from different regions. Therefore, certification is clearly required to protect consumers from disguised and/or low-quality honey. Because leptosperin is stable during storage and specific to manuka honey, its measurement may be applicable for manuka honey authentication. PMID:24941263

  17. Pre-filled syringes: a review of the history, manufacturing and challenges.

    PubMed

    Sacha, Gregory; Rogers, J Aaron; Miller, Reagan L

    2015-01-01

    Pre-filled syringes are convenient devices for the delivery of parenteral medications. They are small which makes them easy to carry and are dependable for delivering a precise dose of medication. These and many other reasons are leading to their growth in the pharmaceutical market. There are a number of review articles that describe the advantages and disadvantages of pre-filled syringes. However, there are few journal articles that present information on their manufacturing and challenges. The intent of this review article is to provide information on the history of the pre-filled syringe, methods of their manufacture, methods of filling syringes as a drug product and to examine the types of syringes available. This type of knowledge can familiarize the formulation scientist with the choices available and their possible challenges. PMID:25589433

  18. Dual Syringe Electrospinning of FNfds-modified Hyaluronic Acid

    NASA Astrophysics Data System (ADS)

    Ji, Yuan; Ghosh, Kaustabh; Shu, Xiaozheng; Sokolov, Jonathan; Prestwich, Glenn; Clark, Richard; Rafailovich, Miriam

    2006-03-01

    We described the fabrication of a unique HA nanofibrous scaffold using dual syringe reactive electrospinning. 3^'-dithiobis(propanoic dihydrazide)-modified HA (HA-DTPH) and Poly (ethylene glycol)-diacrylate (PEGDA) were selected as the cross-linking system. PEO was blended with HA-DTPH to facilitate the fiber formation. Fibronectin functional domains (FNfds) were incorporated with PEGDA and covalently linked to HA via conjugate addition to improve the cell attachment. The as-spun scaffold was soaked into DI water to remove PEO and yield an FNfds-modified HA-DTPH nanofibrous scaffold. Human dermal fibroblasts CF31 were seeded on FNfds-modified HA-DTPH scaffolds. The CF31 fibroblasts showed a unique extended dendritic morphology which is opposed to the typical flattened morphology of cells on regular 2D geometries. Supported by NSF-MRSEC.

  19. 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.

  20. The social geography of AIDS and hepatitis risk: qualitative approaches for assessing local differences in sterile-syringe access among injection drug users.

    PubMed Central

    Singer, M; Stopka, T; Siano, C; Springer, K; Barton, G; Khoshnood, K; Gorry de Puga, A; Heimer, R

    2000-01-01

    While significant gains have been achieved in understanding and reducing AIDS and hepatitis risks among injection drug users (IDUs), it is necessary to move beyond individual-level characteristics to gain a fuller understanding of the impact of social context on risk. In this study, 6 qualitative methods were used in combination with more traditional epidemiologic survey approaches and laboratory bioassay procedures to examine neighborhood differences in access to sterile syringes among IDUs in 3 northeastern cities. These methods consisted of (1) neighborhood-based IDU focus groups to construct social maps of local equipment acquisition and drug use sites; (2) ethnographic descriptions of target neighborhoods; (3) IDU diary keeping on drug use and injection equipment acquisition; (4) ethnographic day visits with IDUs in natural settings; (5) interviews with IDUs about syringe acquisition and collection of syringes for laboratory analysis; and (6) focused field observation and processual interviewing during drug injection. Preliminary findings from each of these methods are reported to illustrate the methods' value in elucidating the impact of local and regional social factors on sterile syringe access. PMID:10897181

  1. Adverse event associated with a change in nonprescription syringe sale policy

    PubMed Central

    Zaller, Nickolas D.; Yokell, Michael A.; Jeronimo, Alexandra; Bratberg, Jeffrey P.; Case, Patricia; Rich, Josiah D.

    2010-01-01

    Objective To report and describe the possible correlation of a change in syringe sale policy at a community pharmacy with an adverse clinical outcome. Setting Providence, RI, in summer 2009. Patient description 27-year-old white woman with a long-standing history of chronic relapsing opiate addiction and human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfection. Case summary The patient presented to the hospital emergency department with 5 days of severe diffuse pain, swelling in her hands and feet, and several days of rigors with fevers, sweats, and chills. She was diagnosed with sepsis resulting from a disseminated methicillin-resistant Staphylococcus aureus (MRSA) infection. The patient was treated with intravenous antibiotics, neurosurgical drainage of an epidural abscess, intensive care unit care for 1 week, and acute hospitalization for 8 weeks. Main outcome measures Not applicable. Results A few weeks before the patient was hospitalized, pharmacists at her local neighborhood pharmacy decided to stop selling syringes in packages of 10. Instead, syringes were sold at a minimum quantity of 100. The patient did not know where to obtain sterile syringes and began reusing syringes. Conclusion The patient introduced pathogenic bacteria from her skin into her bloodstream through unsafe injection practices. The change in syringe sale policy at her local pharmacy likely inadvertently contributed to this severe and life-threatening situation. Consideration of the implications of syringe sale policy must include an understanding of the barriers that influence individual pharmacist’s decisions regarding particular store policies that affect over-the-counter syringe sales. Legalized sale of nonprescription syringes in community pharmacies alone is not enough to curb the epidemic of unsafe injection practices in the United States. All medical risks that are inherent in the use of unsafe syringes, including blood-borne viral pathogens (e.g., HIV, HCV) and

  2. [Comparative evaluation of 3 types of syringes routinely used for arterial gas analysis].

    PubMed

    Bosch, M; Bauzá, F; Togores, B; Agustí, A G

    1997-01-01

    This prospective study evaluates the practical utility of a special plastic syringe for collecting arterial blood samples for gasometry, comparing it to a glass syringe and a conventional plastic one, in 120 patients who came to our hospital for arterial blood analysis for a variety of reasons. The patients were randomly assigned to one of three groups according to type of syringe assigned. Technicians with experience in the technique prepared the syringes and collected the arterial blood samples after providing local anesthesia. The results showed that the special plastic syringe took less time (p < 0.05) to prepare than did the glass or conventional plastic ones. The differences were quite small, however, in absolute terms, with the special syringe requiring 17 seconds less than the glass syringe and 6 seconds less than the plastic one; the practical importance is therefore slight. No other advantages of the special syringe were observed. No patient required more than one puncture to obtain a valid arterial blood sample, the extraction times (time between arterial puncture until end of process) were similar in the three groups of patients, and the presence of post-puncture hematoma was rare in all groups. There were no differences in level of pain reported (on an analog scale) and the subjective quality of the radial pulse wave was good and similar in all three groups. In conclusion, these results show that use of the special syringe offers no important practical advantages for experienced technicians that would justify the higher price. In fact, as the conventional plastic syringes are cheaper, disposable and similarly effective in expert hands, our results suggest that their routine use for collecting arterial blood gas samples can help improve the cost-benefit ratio for a common procedure in pulmonary function units. PMID:9410433

  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

    ... Staff; 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. Reliability based calibration of partial safety factors for design of free pipeline spans

    SciTech Connect

    Ronold, K.O.; Nielsen, N.J.R.; Tura, F.; Bryndum, M.B.; Smed, P.F.

    1995-12-31

    This paper demonstrates how a structural reliability method can be applied as a rational means to analyze free spans of submarine pipelines with respect to failure in ultimate loading, and to establish partial safety factors for design of such free spans against this failure mode. It is important to note that the described procedure shall be considered as an illustration of a structural reliability methodology, and that the results do not represent a set of final design recommendations. A scope of design cases, consisting of a number of available site-specific pipeline spans, is established and is assumed representative for the future occurrence of submarine pipeline spans. Probabilistic models for the wave and current loading and its transfer to stresses in the pipe wall of a pipeline span is established together with a stochastic representation of the material resistance. The event of failure in ultimate loading is considered as based on a limit state which is reached when the maximum stress over the design life of the pipeline exceeds the yield strength of the pipe material. The yielding limit state is considered an ultimate limit state (ULS).

  5. 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.

  6. Human immunodeficiency virus and hepatitis C virus testing services at syringe exchange programs: availability and outcomes.

    PubMed

    Heinzerling, Keith G; Kral, Alex H; Flynn, Neil M; Anderson, Rachel L; Scott, Andrea; Gilbert, Mary L; Asch, Steven M; Bluthenthal, Ricky N

    2007-06-01

    We described the availability and outcomes of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) testing services at syringe exchange programs throughout California, using interviews with 24 syringe exchange program directors and 560 syringe exchange clients. Both HIV and HCV testing services were available in 62% of programs, 21% had HIV testing only, and 17% had neither. Programs administered by health care/social service providers were more likely than independent syringe exchange programs to have HIV and HCV testing services available. Among clients of programs with testing available, clients of illegal programs were significantly less likely than clients of legal programs to have used syringe exchange HIV and HCV testing services. The availability of HIV and HCV testing services at syringe exchange programs varies, and the use of existing testing services by clients is not universal. Efforts to increase both the availability of HIV and HCV testing services at syringe exchange programs and the use of existing testing services are needed. PMID:17481466

  7. Syringe exchange in Canada: good but not enough to stem the HIV tide.

    PubMed

    Hankins, C A

    1998-04-01

    This article provides a historical perspective on the development of syringe exchange in Canada, the Canadian legal and policy context, evaluation and monitoring strategies, and current challenges facing HIV prevention efforts among injecting drug users. Despite the fact that it is legal to sell, exchange, or provide an IDU with a syringe and there are no laws in Canada requiring a physician's prescription to justify possession of a syringe, policy development and programming have not been adequate to hold HIV at bay in several cities across the country. Although there have been concerted efforts by syringe and needle exchange programs to increase the supply of injecting equipment, HIV prevalence continues to rise, provoking a rethinking of the role of syringe exchange. In a coordinated strategy for HIV prevention among drug users in Canada, needle and syringe exchange is not itself in question; however, ghettoization and needle quota systems may have had an adverse impact on prevention programming. A national action plan has been developed which aims to decentralize both methadone maintenance and syringe and needle exchange programs, increase access to detoxification and treatment modalities, and advocate for changes in the criminal justice system and law enforcement practices. PMID:9596380

  8. Sterile syringe access and disposal among injection drug users newly enrolled in methadone maintenance treatment: a cross-sectional survey

    PubMed Central

    McNeely, Jennifer; Arnsten, Julia H; Gourevitch, Marc N

    2006-01-01

    Background We sought to assess injection practices, means of acquiring and disposing of syringes, and utilization and knowledge of harm reduction resources among injection drug users (IDUs) entering methadone maintenance treatment (MMT). Methods Interviews with 100 consecutive patients, including 35 IDUs, entering a MMT program in the Bronx, NY. Results Utilization of unsafe syringe sources was reported by 69% of IDUs in our sample. Most (80%) IDUs reused syringes, and syringe sharing was also common. Fewer than half knew that non-prescription pharmacy purchase of syringes was possible. The most common means of disposing of injecting equipment were the trash (63%) and syringe exchange programs (49%). Conclusions These findings indicate that drug users entering treatment under-utilize sanctioned venues to obtain sterile syringes or safely dispose of used injection equipment. Programs providing services to drug users should adopt a proactive stance to address the safety and health issues faced by injectors. PMID:16503997

  9. Innovative methodology for intercomparison of radionuclide calibrators using short half-life in situ prepared radioactive sources

    SciTech Connect

    Oliveira, P. A.; Santos, J. A. M.

    2014-07-15

    Purpose: An original radionuclide calibrator method for activity determination is presented. The method could be used for intercomparison surveys for short half-life radioactive sources used in Nuclear Medicine, such as{sup 99m}Tc or most positron emission tomography radiopharmaceuticals. Methods: By evaluation of the resulting net optical density (netOD) using a standardized scanning method of irradiated Gafchromic XRQA2 film, a comparison of the netOD measurement with a previously determined calibration curve can be made and the difference between the tested radionuclide calibrator and a radionuclide calibrator used as reference device can be calculated. To estimate the total expected measurement uncertainties, a careful analysis of the methodology, for the case of{sup 99m}Tc, was performed: reproducibility determination, scanning conditions, and possible fadeout effects. Since every factor of the activity measurement procedure can influence the final result, the method also evaluates correct syringe positioning inside the radionuclide calibrator. Results: As an alternative to using a calibrated source sent to the surveyed site, which requires a relatively long half-life of the nuclide, or sending a portable calibrated radionuclide calibrator, the proposed method uses a source preparedin situ. An indirect activity determination is achieved by the irradiation of a radiochromic film using {sup 99m}Tc under strictly controlled conditions, and cumulated activity calculation from the initial activity and total irradiation time. The irradiated Gafchromic film and the irradiator, without the source, can then be sent to a National Metrology Institute for evaluation of the results. Conclusions: The methodology described in this paper showed to have a good potential for accurate (3%) radionuclide calibrators intercomparison studies for{sup 99m}Tc between Nuclear Medicine centers without source transfer and can easily be adapted to other short half-life radionuclides.

  10. Effectiveness of ear syringing in general practice: a randomised controlled trial and patients' experiences.

    PubMed Central

    Memel, David; Langley, Carole; Watkins, Chris; Laue, Barbara; Birchall, Martin; Bachmann, Max

    2002-01-01

    BACKGROUND: Ear syringing is a common procedure performed for a variety of symptoms in primary care. Reports of its effectiveness vary considerably and no randomised controlled trials (RCTs) have been performed. AIM: To estimate the effect of ear syringing on hearing thresholds and on symptoms leading to ear syringing in general practice. DESIGN OF STUDY: Randomised single-blind controlled trial. Before-and-after self-assessments of symptoms. SETTING: Patients from three general practices in the Bristol area attending twice-weekly clinics dedicated to ear syringing over a 12-week period. METHOD: Patients were randomly assigned to have their hearing tested before and after ear syringing, or twice before ear syringing. Changes in hearing threshold were measured by pure tone audiometry (PTA). All patients completed sef-assessment forms of symptoms using Likert scales before, and one week after, ear syringing. RESULTS: Hearing threshold improved by 10 dB or more in 34% (95% confidence interval [CI] = 21% to 47%) of the intervention group and 1.6% of control group (number needed to treat = 3.1, 95% CI = 2.2 to 5.2, P<0.001). The levels of improvement in the intervention group ranged between 15 dB and 36 dB. The symptoms that most commonly improved included hearing on the phone, pain, a feeling of blocked ears, and hearing one-to-one. There was a strong relationship between the change thresholds, as measure using PTA, and self-reports of hearing improvement. Secondary analysis was unable to identify predictors of objectively measured improvement. CONCLUSION: Ear syringing improved hearing threshold in a substantial proportion of patients. An even larger proportion reported an improvement in symptoms. It was not possible to predict which patients would benefit. PMID:12434959

  11. Microbial Contamination on Disposable Hypodermic Syringes Prior to Sterilization by Ionizing Radiation1

    PubMed Central

    Cook, A. M.; Berry, R. J.

    1968-01-01

    A large number of syringes were taken from the production lines of three independent manufacturers; the numbers and types of microorganisms contaminating these randomly sampled syringes were assessed in the laboratories maintained by each of these manufacturers for routine sterility testing, according to a standard protocol devised by the Research Committee of the UK Panel on Gamma and Electron Irradiation, which coordinated the investigation and analyzed the results. Items produced by a manufacturer were assessed for microbiological contamination both in their own laboratories and in the laboratories of the other manufacturers. The level of “false-positive” results was determined independently for each laboratory by the testing of “known sterile” items which had been subjected to the radiation-sterilization process. Both the percentage of syringes initially sterile and the average number of organisms per contaminated syringe differed among the three manufacturers. When corrected for interlaboratory differences, the number of syringes initially sterile ranged from 16 to 48%, and the mean number of organisms per contaminated syringe was 20 to 70. Of 964 syringes tested by all three laboratories, only one contained over 1,000 aerobic organisms (1,133). The most common organisms found were coagulase-negative, gram-positive cocci. Two manufacturers assessed contamination by anaerobic organisms; of 610 syringes, 1 contained 4,275 organisms and 3 more had 100 to 1,000 organisms, but 488 (80%) were uncontaminated by anaerobes. The results are discussed in the context of the choice of radiation dose necessary for the sterilization of medical products manufactured under controlled hygienic conditions. PMID:5675506

  12. Microbial contamination on disposable hypodermic syringes prior to sterilization by ionizing radiation.

    PubMed

    Cook, A M; Berry, R J

    1968-08-01

    A large number of syringes were taken from the production lines of three independent manufacturers; the numbers and types of microorganisms contaminating these randomly sampled syringes were assessed in the laboratories maintained by each of these manufacturers for routine sterility testing, according to a standard protocol devised by the Research Committee of the UK Panel on Gamma and Electron Irradiation, which coordinated the investigation and analyzed the results. Items produced by a manufacturer were assessed for microbiological contamination both in their own laboratories and in the laboratories of the other manufacturers. The level of "false-positive" results was determined independently for each laboratory by the testing of "known sterile" items which had been subjected to the radiation-sterilization process. Both the percentage of syringes initially sterile and the average number of organisms per contaminated syringe differed among the three manufacturers. When corrected for interlaboratory differences, the number of syringes initially sterile ranged from 16 to 48%, and the mean number of organisms per contaminated syringe was 20 to 70. Of 964 syringes tested by all three laboratories, only one contained over 1,000 aerobic organisms (1,133). The most common organisms found were coagulase-negative, gram-positive cocci. Two manufacturers assessed contamination by anaerobic organisms; of 610 syringes, 1 contained 4,275 organisms and 3 more had 100 to 1,000 organisms, but 488 (80%) were uncontaminated by anaerobes. The results are discussed in the context of the choice of radiation dose necessary for the sterilization of medical products manufactured under controlled hygienic conditions. PMID:5675506

  13. Strong composition-dependent variation of MCs + calibration factors in TiO x and GeO x ( x ≤ 2) films

    NASA Astrophysics Data System (ADS)

    Gnaser, Hubert; Le, Yongkang; Su, Weifeng

    2006-07-01

    The emission of MCs + secondary ions (M designates the analyte species) from TiO x (0.2 ≤ x ≤ 2) and GeO x (0.001 ≤ x ≤ 0.8) films under Cs + bombardment was examined. The relative calibration factors of OCs +/TiCs + and OCs +/GeCs + were determined and were found to depend pronouncedly on the O/Ti and O/Ge atomic concentration ratios. Specifically, with increasing oxygen content OCs + ions form much more efficiently (as compared to TiCs + or GeCs + ions), an enhancement amounting to more than a factor of 10 for the highest oxygen concentrations. Concurrently, the formation of TiOCs + or GeOCs + ions increases drastically. For both oxide systems, an empirical relation for the oxygen-concentration dependence of the relative calibration factors could be established.

  14. Freeze-drying in novel container system: Characterization of heat and mass transfer in glass syringes.

    PubMed

    Patel, Sajal M; Pikal, Michael J

    2010-07-01

    This study is aimed at characterizing and understanding different modes of heat and mass transfer in glass syringes to develop a robust freeze-drying process. Two different holder systems were used to freeze-dry in syringes: an aluminum (Al) block and a plexiglass holder. The syringe heat transfer coefficient was characterized by a sublimation test using pure water. Mannitol and sucrose (5% w/v) were also freeze-dried, as model systems, in both the assemblies. Dry layer resistance was determined from manometric temperature measurement (MTM) and product temperature was measured using thermocouples, and was also determined from MTM. Further, freeze-drying process was also designed using Smart freeze-dryer to assess its application for freeze-drying in novel container systems. Heat and mass transfer in syringes were compared against the traditional container system (i.e., glass tubing vial). In the Al block, the heat transfer was via three modes: contact conduction, gas conduction, and radiation with gas conduction being the dominant mode of heat transfer. In the plexiglass holder, the heat transfer was mostly via radiation; convection was not involved. Also, MTM/Smart freeze-drying did work reasonably well for freeze-drying in syringes. When compared to tubing vials, product temperature decreases and hence drying time increases in syringes. PMID:20166199

  15. Correlates of unsafe syringe acquisition and disposal among injection drug users in Baltimore, Maryland.

    PubMed

    Golub, Elizabeth T; Bareta, Joseph C; Mehta, Shruti H; McCall, Lisa D; Vlahov, David; Strathdee, Steffanie A

    2005-01-01

    Because multi-person syringe use is the most common vehicle for HIV and hepatitis C virus transmission among injection drug users (IDUs), safe sources of sterile syringes and safe methods of disposal are necessary to curb these epidemics. We examined syringe acquisition and disposal in a cohort of IDUs in Baltimore. Between January 1, 1998 and December 31, 2001, 1034 participants reported on syringe acquisition at 3492 visits, and 953 reported on disposal at 2569 visits. Participants were 69.9% male, 93.9% African-American, and median age was 44. Syringes were acquired exclusively from unsafe sources at 32.3% of visits, while exclusively unsafe disposal was reported at 59.3% of visits. Significant correlates of unsafe acquisition were: attending shooting galleries, anonymous sex, sharing needles, smoking crack, and emergency room visits. Significant correlates of unsafe disposal were: injecting speedball, no methadone treatment, acquiring safely, and frequent injection. Having a primary source of medical care was associated with safe acquisition, but unsafe disposal. IDUs continue to acquire safely but dispose unsafely, especially among those with a primary source of care; this suggests that messages about safe disposal are not being disseminated as widely as those about acquisition. These data suggest the need for a more active program involving pharmacists, an expanded syringe access program, and better efforts to enhance safe disposal. PMID:16419554

  16. Hidden reality on the introduction of auto-disable syringes in developing countries.

    PubMed

    Kuroiwa, Chushi; Suzuki, Akiko; Yamaji, Yoshio; Miyoshi, Miki

    2004-12-01

    With the growing concerns about the risk of unsafe injections (e.g. unsterilized injection practices), WHO, UNICEF and UNFPA decided to introduce the auto-disable (AD) syringe for immunization in the world. The AD syringe is designed to be automatically locked after a single use, hence no chance of reuse. Consequently, the risk of infection can be reduced for the recipient. On the other hand, the management of increased medical waste is becoming difficult, as the waste volume of AD syringes would be 200 times as much as those of sterilizable syringes. The used and improperly disposed AD syringes could be a huge source of blood-borne infections and environmental pollution at the community level. This study attempted to explore the present situation with regard to the introduction of AD syringes for immunization in Lao PDR. We conclude that reviewing the present 'safe injection' policy is urgently required in Lao PDR, as well as in other developing countries where the disposal system for medical wastes is not yet well established. PMID:15916108

  17. 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

  18. Microparticle-associated tissue factor activity measured with the Zymuphen MP-TF kit and the calibrated automated thrombogram assay.

    PubMed

    Hellum, Marit; Øvstebø, Reidun; Trøseid, Anne-Marie S; Berg, Jens P; Brandtzaeg, Petter; Henriksson, Carola E

    2012-09-01

    There is increasing clinical interest for measuring microparticle (MP)-associated tissue factor (TF) activity owing to its possible role as a prothrombotic biomarker in a variety of diseases. However, the methods used are to various extents hampered by lack of (pre)analytical standardization as well as limited published documentation. The objective of this study was to evaluate the performance of the Zymuphen MP-TF kit and the calibrated automated thrombogram (CAT) assay in measuring MP-associated TF activity in plasma using a Neisseria meningitidis (Nm)-stimulated whole blood model. In addition, (pre)analytical variables like centrifugation procedures, freezing/thawing and the effect of addition of exogenous phosphatidylserine in plasma were evaluated in the CAT assay. Citrate-anticoagulated blood was stimulated with Nm bacteria for 4 h before platelet-poor plasma (PPP) or platelet-free plasma (PFP) were prepared and assayed with either of the two methods. Nm dose-dependently (10-10 bacteria/ml) induced TF-specific activity, measured as decreased lagtimes, in the CAT assay. The Zymuphen MP-TF kit also detected TF activity, although much higher Nm doses (10 bacteria/ml) were required to achieve measurable levels. Neither freezing/thawing nor the use of PPP vs. PFP influenced the TF activity, measured over a broad range of lagtimes, in the CAT assay. In conclusion, changes in lagtime in the CAT assay reflected levels of MP-associated TF activity in a more sensitive manner than the Zymuphen MP-TF kit did, in our Nm-stimulated whole blood system. PMID:22732249

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

    PubMed Central

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

    2013-01-01

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

  20. 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.

  1. 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

  2. DC non-thermal atmospheric-pressure plasma jet generated using a syringe needle electrode

    NASA Astrophysics Data System (ADS)

    Matra, Khanit

    2016-07-01

    Non-thermal plasma jet was generated by applying a dc source voltage between the syringe needle anode with flowing Argon gas and a planar or a hollow copper cathode in an atmospheric-pressure environment. The two operating discharge modes, which were self-pulsing and a continuous discharge mode, these were mainly controlled by the limitations of the current flowing in the discharge circuit. A ballast resistor was an important factor in affecting the limitations of the operating discharge mode. The gas breakdown was initially generated in the self-pulsing discharge mode at the source voltage of 1.2 kV. This was slightly higher than the breakdown voltage at the experimental condition of 1 lpm of Argon and a 1 mm electrode gap distance. The peak self-pulsing discharge currents were up to 15–20 A with a self-pulsing frequency in the range of 10–20 kHz. The continuous discharge mode could be observed at the higher source voltage with the continuous discharge current within the range of a few milliamperes.

  3. Incarceration is associated with used syringe lending among active injection drug users with detectable plasma HIV-1 RNA: a longitudinal analysis

    PubMed Central

    2013-01-01

    Background Informed by recent studies demonstrating the central role of plasma HIV-1 RNA viral load (VL) on HIV transmission, interventions to employ HIV antiretroviral treatment as prevention (TasP) are underway. To optimize these efforts, evidence is needed to identify factors associated with both non-suppressed VL and HIV risk behaviours. Thus, we sought to assess the possible role played by exposure to correctional facilities on VL non-suppression and used syringe lending among HIV-seropositive people who use injection drugs (PWID). Methods We used data from the ACCESS study, a community-recruited prospective cohort. We used longitudinal multivariate mixed-effects analyses to estimate the relationship between incarceration and plasma HIV-1 RNA > 500 copies/mL among antiretroviral therapy (ART)-exposed active PWID and, during periods of non-suppression, the relationship between incarceration and used syringe lending. Results Between May 1996 and March 2012, 657 ART-exposed PWID were recruited. Incarceration was independently associated with higher odds of VL non-suppression (Adjusted Odds Ratio [AOR] = 1.54, 95% Confidence Interval [95% CI]: 1.10, 2.16). In a separate multivariate model restricted to periods of VL non-suppression, incarceration was independently associated with lending used syringes (AOR = 1.81, 95% CI: 1.03, 3.18). Conclusions The current findings demonstrate that incarceration is associated with used syringe lending among active PWID with detectable plasma HIV-1 RNA. Our results provide a possible pathway for the commonly observed association between incarceration and increased risk of HIV transmission. Our results suggest that alternatives to incarceration of non-violent PWID and evidence-based combination HIV prevention interventions for PWID within correctional facilities are urgently needed. PMID:24289651

  4. 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

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

    PubMed

    Melwanki, Mahaveer B; Fuh, Ming-Ren

    2008-07-11

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

  6. Training students to use syringe pumps: an experimental comparison of e-learning and classroom training.

    PubMed

    Grundgeiger, Tobias; Kolb, Lorenz; Korb, Maximilian O; Mengelkamp, Christoph; Held, Volker

    2016-04-01

    The inadequate use of syringe pumps can jeopardize patient safety, and syringe pump trainings are conducted to manage this risk. A critical step in this risk management process is the learning success of trainees. In the present paper, we compared an e-learning approach with standard classroom training in learning success effectives, trainees' opinion on the trainings, and investigated the relation between technological affinity and learning success. The results showed that e-learning was as effective as classroom training but nursing students' confidence in using the pump and satisfaction with the training was decreased for e-learning compared with classroom training. We discuss the results in context of the nursing e-learning literature. Finally, we discuss the literature for risk identification, risk analysis, risk treatment, and risk monitoring and control in the context of syringe pump training and add the lessons learned from the evaluated e-learning program. PMID:26368041

  7. 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

  8. 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,…

  9. Effect of polarization and geometric factors on quantitative laser-induced fluorescence- to-Raman intensity ratios of water samples and a new calibration technique

    NASA Astrophysics Data System (ADS)

    Sivaprakasam, Vasanthi; Killinger, Dennis K.

    2003-09-01

    A 266-nm laser-induced fluorescence system was used to study the effect of polarization of the excitation source and geometry of the collection optics on the ratio of the signal from a fluorescence standard, quinine sulfate, and the Raman scatter from water. Although the ratio is sometimes considered to be a constant and is used for intersystem comparisons, our studies showed that the Raman signal and, thus, the ratio can vary by a factor of up to 3.6. These experimental values agree with previous studies by others involving gas and flame Raman spectroscopy and suggest a new calibration method for intersystem comparison of different fluorescence systems.

  10. What's community got to do with it? Implementation models of syringe exchange programs.

    PubMed

    Downing, Moher; Riess, Thomas H; Vernon, Karen; Mulia, Nina; Hollinquest, Marilyn; McKnight, Courtney; Jarlais, Don C Des; Edlin, Brian R

    2005-02-01

    Syringe exchange programs (SEPs) have been shown to be highly effective in reducing HIV transmission among injection drug users (IDUs). Despite this evidence, SEPs have not been implemented in many communities experiencing HIV epidemics among IDUs. We interviewed 17 key informants in nine U.S. cities to identify factors and conditions that facilitated or deterred the adoption of SEPs. Cities were selected to represent diversity in size, geographic location, AIDS incidence rates, and SEP implementation. Key informants included HIV prevention providers, political leaders, community activists, substance use and AIDS researchers, and health department directors. SEPs were established by one or more of three types of implementation models: (a) broad community coalition support, (b) community activist initiative, and (c) top-down decision making by government authorities. In each model, coalition building and community consultation were critical steps for the acceptance and sustainability of SEPs. When others were not prepared to act, community activists spearheaded SEP development, taking risks in the face of opposition, but often lacked the resources to sustain their efforts. Leadership from politicians and public health officials provided needed authority, clout, and access to resources. Researchers and scientific findings lent force and legitimacy to the effort. Rather than adopting adversarial positions, successful SEP implementers worked with or avoided the opposition. Fear of repercussions and lack of leadership were the greatest barriers to implementing SEPs. Communities that successfully implemented SEPs were those with activists willing to push the agenda, public officials willing to exercise leadership, researchers able to present authoritative findings, and proponents who effectively mobilized resources and worked to build community coalitions, using persistent but nonadversarial advocacy. PMID:15843111

  11. Childhood sexual abuse and syringe sharing among people who inject drugs

    PubMed Central

    Lee, William; Ti, Lianping; Marshall, Brandon D.L.; Dong, Huiru; Wood, Evan; Kerr, Thomas

    2014-01-01

    Childhood sexual abuse is associated with adverse health outcomes. However, the impact of sexual abuse on HIV risk behaviors among people who inject drugs (IDU) has not been thoroughly characterized. We therefore sought to identify whether childhood sexual abuse was associated with syringe sharing among a sample of IDU in Vancouver, Canada. We assessed sexual abuse among two cohorts of IDUs via the Childhood Trauma Questionnaire (CTQ). Multivariate logistic regression was used to estimate the relationship between childhood sexual abuse and syringe sharing. In total, 1380 IDU were included in the study, and 426 (30.9%) IDU reported childhood sexual abuse. Syringe sharing (Adjusted Odds Ratio = 1.83, 95% Confidence Interval: 1.28–2.60) remained independently associated with childhood sexual abuse after adjustment for potential confounders. Given that a history of childhood sexual abuse appears to be elevated among IDU who engage in HIV risk behaviors (i.e., syringe sharing), HIV prevention efforts should include efforts to address historical trauma in this population. PMID:25428283

  12. Suppression of Methionine Oxidation of a Pharmaceutical Antibody Stored in a Polymer-Based Syringe.

    PubMed

    Masato, Amano; Kiichi, Fukui; Uchiyama, Susumu

    2016-02-01

    Oxidation of methionine residues is one of the well-known deteriorations in monoclonal antibody (mAb) therapeutics. Because methionine oxidation may affect their efficacy and pharmacokinetic profile, oxidation levels should be strictly controlled during their storage period. In this study, we revealed that when a therapeutic antibody was filled into a cyclo olefin polymer-based syringe and stored in a blister pack with an oxygen absorber, the methionine oxidation production under thermal or light stress was suppressed because of the reduction in the concentration of dissolved oxygen. Also unexpectedly, fewer amounts of the high-molecular-weight species and the acidic variants of the antibody were generated under thermal or light stress. Although the high-molecular-weight species contains methionine oxidants at similar levels to those in a monomer species, they were likely to be constituted from a higher amount of the oxidative species of internal disulfide linkage, tyrosine, or histidine. Because the dissolved oxygen could be readily removed from the mAb solution in the polymer-based syringe owing to its high gas permeability, this study shows the advantages of the polymer-based syringe with an oxygen absorber over glass syringes in terms of the suppression of the methionine oxidation and oxidative high molecular species. PMID:26462145

  13. 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…

  14. 41 CFR 109-27.5009 - Control of hypodermic needles and syringes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Control of hypodermic... SUPPLY AND PROCUREMENT 27-INVENTORY MANAGEMENT 27.50-Inventory Management Policies, Procedures, and Guidelines § 109-27.5009 Control of hypodermic needles and syringes. Effective procedures and practices...

  15. 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.

  16. Childhood Sexual Abuse and Syringe Sharing Among People Who Inject Drugs.

    PubMed

    Lee, William; Ti, Lianping; Marshall, Brandon D L; Dong, Huiru; Wood, Evan; Kerr, Thomas

    2015-08-01

    Childhood sexual abuse is associated with adverse health outcomes. However, the impact of sexual abuse on HIV risk behaviors among people who inject drugs (IDU) has not been thoroughly characterized. We therefore sought to identify whether childhood sexual abuse was associated with syringe sharing among a sample of IDU in Vancouver, Canada. We assessed sexual abuse among two cohorts of IDUs via the Childhood Trauma Questionnaire. Multivariate logistic regression was used to estimate the relationship between childhood sexual abuse and syringe sharing. In total, 1380 IDU were included in the study, and 426 (30.9 %) IDU reported childhood sexual abuse. Syringe sharing (Adjusted Odds Ratio = 1.83, 95 % Confidence Interval 1.28-2.60) remained independently associated with childhood sexual abuse after adjustment for potential confounders. Given that a history of childhood sexual abuse appears to be elevated among IDU who engage in HIV risk behaviors (i.e., syringe sharing), HIV prevention efforts should include efforts to address historical trauma in this population. PMID:25428283

  17. Sharing of Needles and Syringes among Men Who Inject Drugs: HIV Risk in Northwest Bangladesh

    PubMed Central

    Pasa, M. Kamal; Alom, Kazi Robiul; Bashri, Zubaida; Vermund, Sten H.

    2016-01-01

    Introduction Injection drug use is prevalent in northwestern Bangladesh. We sought to explore the context of needle/syringe sharing among persons who inject drugs (PWID), examining risk exposures to blood-borne infections like the human immunodeficiency virus (HIV) and hepatitis in a region where these dual epidemics are likely to expand. Methods We used a qualitative research approach to learn about injection practices, conducting 60 in-depth interviews among PWID. We then conducted 12 focus group discussions (FGDs) that generated a checklist of salient issues, and followed up with personal observations of typical days at the drug-use venues. Content and interpretative frameworks were used to analyze qualitative information and socio-demographic information, using SPSS software. Results We found that needle/syringe-sharing behaviours were integrated into the overall social and cultural lives of drug users. Sharing behaviours were an central component of PWID social organization. Sharing was perceived as an inherent element within reciprocal relationships, and sharing was tied to beliefs about drug effects, economic adversity, and harassment due to their drug user status. Carrying used needles/syringes to drug-use venues was deemed essential since user-unfriendly needle-syringe distribution schedules of harm reduction programmes made it difficult to access clean needles/syringes in off-hours. PWID had low self-esteem. Unequal power relationships were reported between the field workers of harm reduction programmes and PWID. Field workers expressed anti-PWID bias and judgmental attitudes, and also had had misconceptions about HIV and hepatitis transmission. PWID were especially disturbed that no assistance was forthcoming from risk reduction programme staff when drug users manifested withdrawal symptoms. Conclusion Interventions must take social context into account when scaling up programmes in diverse settings. The social organization of PWID include values that

  18. In-syringe extraction using dissolvable layered double hydroxide-polymer sponges templated from hierarchically porous coordination polymers.

    PubMed

    Ghani, Milad; Frizzarin, Rejane M; Maya, Fernando; Cerdà, Víctor

    2016-07-01

    Herein we report the use of cobalt porous coordination polymers (PCP) as intermediates to prepare advanced extraction media based on layered double hydroxides (LDH) supported on melamine polymer foam. The obtained dissolvable Ni-Co LDH composite sponges can be molded and used as sorbent for the in-syringe solid-phase extraction (SPE) of phenolic acids from fruit juices. The proposed sorbent is obtained due to the surfactant-assisted self-assembly of Co(II)/imidazolate PCPs on commercially available melamine foam, followed by the in situ conversion of the PCP into the final dissolvable LDH coating. Advantageous features for SPE are obtained by using PCPs with hierarchical porosity (HPCPs). The LDH-sponge prepared using intermediate HPCPs (HLDH-sponge) is placed in the headspace of a glass syringe, enabling flow-through extraction followed by analyte elution by the dissolution of the LDH coating in acidic conditions. Three phenolic acids (gallic acid, p-hydroxybenzoic acid and caffeic acid) were extracted and quantified using high performance liquid chromatography. Using a 5mL sample volume, the obtained detection limits were 0.15-0.35μgL(-1). The proposed method for the preparation of HLDH-sponges showed a good reproducibility as observed from the intra- and inter-day RSD's, which were <10% for all analytes. The batch-to-batch reproducibility for three different batches of HLDH-sponges was 10.6-11.2%. Enrichment factors of 15-21 were obtained. The HLDH-sponges were applied satisfactorily to the determination of phenolic acids in natural and commercial fruit juices, obtaining relative recoveries among 89.7-95.3%. PMID:27247213

  19. 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

  20. Monte Carlo-derived TLD cross-calibration factors for treatment verification and measurement of skin dose in accelerated partial breast irradiation.

    PubMed

    Garnica-Garza, H M

    2009-03-21

    Monte Carlo simulation was employed to calculate the response of TLD-100 chips under irradiation conditions such as those found during accelerated partial breast irradiation with the MammoSite radiation therapy system. The absorbed dose versus radius in the last 0.5 cm of the treated volume was also calculated, employing a resolution of 20 microm, and a function that fits the observed data was determined. Several clinically relevant irradiation conditions were simulated for different combinations of balloon size, balloon-to-surface distance and contents of the contrast solution used to fill the balloon. The thermoluminescent dosemeter (TLD) cross-calibration factors were derived assuming that the calibration of the dosemeters was carried out using a Cobalt 60 beam, and in such a way that they provide a set of parameters that reproduce the function that describes the behavior of the absorbed dose versus radius curve. Such factors may also prove to be useful for those standardized laboratories that provide postal dosimetry services. PMID:19229101

  1. Anemometer calibrator

    NASA Technical Reports Server (NTRS)

    Bate, T.; Calkins, D. E.; Price, P.; Veikins, O.

    1971-01-01

    Calibrator generates accurate flow velocities over wide range of gas pressure, temperature, and composition. Both pressure and flow velocity can be maintained within 0.25 percent. Instrument is essentially closed loop hydraulic system containing positive displacement drive.

  2. Spring active drain using bladder (50–60 ml) syringe (De Adotey’s drain)

    PubMed Central

    Igwe, Patrick Okechukwu; Dodiyi-Manuel, Amabra; Adotey, Jacob Molai

    2016-01-01

    Introduction Closed active drainage system with a syringe is an accepted way to let out fluid in a surgical wound. We present a simple spring active (negative suction) drainage (SAD) system using locally improvised metallic spring and 60 ml (bladder syringe); SAD of Adotey, a newly designed compression–expansion spring mechanism which serves especially in situations where an active drainage system is of utmost importance. Conclusion De Adotey's drain is a 60 ml bladder syringe with spring mechanism which is used to provide a negative pressure as an active drain. PMID:26785081

  3. 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

  4. Stability of succinylcholine chloride injection at ambient temperature and 4 deg C in polypropylene syringes.

    PubMed

    Storms, Meredith L; Stewart, James T; Warren, Flynn W

    2003-01-01

    The stability of 20-mg/mL succinylcholine chloride injection in 12-mL polypropylene syringes stored at ambient temperature and 4 deg C for up to 90 days was investigated. Concentration levels of succinylcholine chloride injection were determined at 0, 1, 4, 7, 15, 30, 45, 60, and 90 days after preparation of the syringes by means of a high-performance liquid chromatographic stability-indicating assay. Methylparaben, which was added as a preservative, did not interfere with the assay. The loss in potency was less than 10% after 45 days of storage at 25 deg C and less than 1% after 90 days of storage at 4 deg C. The pH of succinylcholine chloride injection did not change appreciably during the 90-day study period. PMID:23979509

  5. Analysis: the impact of needle, syringe, and lancet disposal on the community.

    PubMed

    Gold, Kathleen

    2011-07-01

    There are over 7.5 billion needles and syringes used outside of the health care system each year by individuals with diabetes, migraines, allergies, infertility, arthritis, HIV, hepatitis, multiple sclerosis, osteoporosis, psoriasis, or other conditions. Disposal of needles, syringes, lancets, and other medical products are not regulated in the home, while these same products used in health care facilities are strictly regulated. Home-generated medical waste is routinely placed into curbside trash, placing sanitation workers and custodial personnel at personal risk of a needle-stick injury. The Coalition for Safe Community Needle Disposal is working to establish a solution that is satisfactory to all stakeholders, sharing the burden of these programs with the pharmaceutical industry, medical device industry, waste management industry, recycling companies, and local and state governments. PMID:21880224

  6. 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.

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

    PubMed Central

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

    2007-01-01

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

  8. Stability of Commercially Available Grape and Compounded Cherry Oral Vancomycin Preparations Stored in Syringes and Cups.

    PubMed

    Kirk, Loren; Lewis, Paul; Luu, Yao; Brown, Stacy

    2016-01-01

    The purpose of this study was to evaluate the stability of two preparations of vancomycin oral solution in two different storage containers, capped amber oral-dosing syringes and heat-sealed oral-dosing cups, stored under refrigerated conditions. Commercially available grape-flavored vancomycin oral preparation and compounded vancomycin for intravenous use in cherry syrup oral preparation were divided into 5-mL aliquots into heat-sealed plastic dosing cups and capped oral-dosing syringes. All samples were stored under refrigeration (2°C to 8°C) and evaluated at days 0, 3, 7, 14, 30, 60, and 90. For each evaluation, samples were visually inspected and analyzed for potency using a stability-indicating high-performance liquid chromatographic method with ultraviolet detection. Over the study period, at least 90% of the initial concentrations for the preparation and the product in both storage containers were retained at 60 days. The commercially available oral vancomycin further demonstrated stability within 90% out to 90 days in the syringe and the unit-dose cups. Visual inspection revealed no changes in the grape-flavored vancomycin oral preparation, but a detectable red-dye precipitate could be seen in the crevices of the dosing cups from the vancomycin in cherry syrup oral preparation after 60 days. Commercially available grape-flavored vancomycin oral preparation was stable up to 90 days, and com- pounded vancomycin for intravenous use in cherry syrup oral preparation maintained stability for 60 days when dispensed in capped amber polypropylene oral-dosing syringes and heat-sealed plastic dosing cups when stored at refrigerated conditions. PMID:27323427

  9. Protection Device Made of a Modified Syringe for Muscle Protection During Cranial Perforation: Technical Note.

    PubMed

    Matano, Fumihiro; Mizunari, Takayuki; Koketsu, Kenta; Fujiki, Yu; Kubota, Asami; Kobayashi, Shiro; Murai, Yasuo; Morita, Akio

    2016-05-01

    In neurosurgical procedures, avoiding damage of surrounding tissues such as muscle and periosteum during a craniotomy is important for esthetic and other reasons. We devised a protection tool by using an amputated syringe barrel to cover the perforating drill and protect temporal muscle damage. This device made it possible to prevent damage to surrounding tissues, such as the muscle and periosteum, during cranial perforation. This method could be useful as it is cost-effective, simple, and versatile. PMID:26773982

  10. 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

  11. Drugs given by a syringe driver: a prospective multicentre survey of palliative care services in the UK.

    PubMed

    Wilcock, Andrew; Jacob, Jayin K; Charlesworth, Sarah; Harris, Elayne; Gibbs, Margaret; Allsop, Helen

    2006-10-01

    The use of a syringe driver to administer drugs by continuous subcutaneous infusion is common practice in the UK. Over time, drug combinations used in a syringe driver are likely to change and the aim of this survey was to obtain a more recent snapshot of practice. On four separate days, at two-week intervals, a questionnaire was completed for every syringe driver in use by 15 palliative care services. Of 336 syringe drivers, the majority contained either two or three drugs, but one-fifth contained only one drug. The median (range) volume of the infusions was 15 (9.5-48) mL, and duration of infusion was generally 24 hours. Only one combination was reported as visually incompatible, and there were 13 site reactions (4% of total). Laboratory physical and chemical compatibility data are available for less than half of the most frequently used combinations. PMID:17060264

  12. 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

  13. Potential Air Contamination During CO{sub 2} Angiography Using a Hand-Held Syringe: Theoretical Considerations and Gas Chromatography

    SciTech Connect

    Cho, David R.; Cho, Kyung J. Hawkins, Irvin F.

    2006-08-15

    Purpose. To assess air contamination in the hand-held syringes currently used for CO{sub 2} delivery and to determine whether there is an association between their position and the rate of air contamination. Methods. Assessment of air contamination in the syringe (20 ml) included theoretical modeling, mathematical calculation, and gas chromatography (GC). The model was used with Fick's first law to calculate the diffusion of CO{sub 2} and the amount of air contamination. For GC studies, the syringes were placed in the upright, horizontal, and inverted positions and gas samples were obtained after 5, 10, 20, 30, and 60 min. All trials with each position for each sampling time were performed five times. Results. The amounts of air contamination with time calculated mathematically were 5-10% less than those of GC. With the diffusivity of air-CO{sub 2} at 0.1599 cm{sup 2}/sec (9.594 cm{sup 2}/min), air contamination was calculated to be 60% at 60 min. With GC air contamination was 13% at 5 min, 31% at 20 min, 43% at 30 min, and 68% at 60 min. There was no difference in air contamination between the different syringe positions. Conclusion. Air contamination occurs in hand-held syringes filled with CO{sub 2} when they are open to the ambient air. The amounts of air contamination over time are similar among syringes placed in the upright, horizontal, and inverted positions.

  14. Iterative Magnetometer Calibration

    NASA Technical Reports Server (NTRS)

    Sedlak, Joseph

    2006-01-01

    This paper presents an iterative method for three-axis magnetometer (TAM) calibration that makes use of three existing utilities recently incorporated into the attitude ground support system used at NASA's Goddard Space Flight Center. The method combines attitude-independent and attitude-dependent calibration algorithms with a new spinning spacecraft Kalman filter to solve for biases, scale factors, nonorthogonal corrections to the alignment, and the orthogonal sensor alignment. The method is particularly well-suited to spin-stabilized spacecraft, but may also be useful for three-axis stabilized missions given sufficient data to provide observability.

  15. 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

  16. 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.

  17. 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.

  18. 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

  19. Internalized stigma and sterile syringe use among people who inject drugs in New York City, 2010-2012

    PubMed Central

    Rivera, Alexis V.; DeCuir, Jennifer; Crawford, Natalie D.; Amesty, Silvia; Lewis, Crystal Fuller

    2014-01-01

    Background Little is known on the effect of stigma on the health and behavior of people who inject drugs (PWID). PWID may internalize these negative attitudes and experiences and stigmatize themselves (internalized stigma). With previous research suggesting a harmful effect of internalized stigma on health behaviors, we aimed to determine socio-demographic characteristics and injection risk behaviors associated with internalized PWID-related stigma in New York City (NYC). Methods Three NYC pharmacies assisted in recruiting PWID. Pharmacy-recruited PWID syringe customers received training in recruiting up to three of their peers. Participants completed a survey on injection behaviors and PWID-related stigma. Among HIV-negative PWID (n=132), multiple linear regression with GEE (to account for peer network clustering) was used to examine associations with internalized PWID-related stigma. Results Latinos were more likely to have higher internalized stigma, as were those with lower educational attainment. Those with higher internalized stigma were more likely to not use a syringe exchange program (SEP) recently, although no association was found with the recent use of pharmacies for syringes. Lastly, higher internalized stigma was related to less than 100% use of pharmacies or SEPs for syringe needs. Conclusions These data suggest that PWID with higher internalized stigma are less likely to consistently use sterile syringe sources in urban settings with multiple sterile syringe access points. These results support the need for individual-and structural-level interventions that address PWID-related stigma. Future research is needed to examine why PWID with higher internalized stigma have less consistent use of public syringe access venues. PMID:25307745

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

    PubMed Central

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

    2012-01-01

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

  1. Drugs and syringe drivers: a survey of adult specialist palliative care practice in the United Kingdom and Eire.

    PubMed

    O'Doherty, C A; Hall, E J; Schofield, L; Zeppetella, G

    2001-03-01

    Subcutaneous delivery of drugs using a syringe driver is common practice within specialist palliative care units. There is, however, little documented information regarding clinical practice. A survey performed in 1992 reported that at least 28 drugs were used in combination with others in a single syringe driver. The aim of the present study was to reassess practice in this field and to enquire more specifically about newer drugs. Postal questionnaires were sent to all adult specialist palliative care in-patient units in the UK and Eire (n = 208). One hundred and sixty-five units (79%) responded. The most common syringe driver in use was the Graseby 26 (61% of responding units). Most units delivered the contents of the syringe over 24 h, and water was usually used as the diluent in 90% of cases. The maximum number of drugs that respondents were prepared to mix in a single syringe was usually three (51%) or four (35%). In the UK, all units used diamorphine in doses from 2.5 mg/24 h upwards. All respondents also used haloperidol, in doses from 0.5 to 60 mg/24 h. A total of 28 different drugs were used in syringe drivers. The most common combinations were diamorphine and midazolam (37%), diamorphine and levomepromazine (35%), diamorphine and haloperidol (33%), and diamorphine and cyclizine (31%). In conclusion, there is much in common with regard to the way in which drugs are delivered in syringe drivers. However, a wide variety of drugs and drug combinations are still in use. PMID:11301666

  2. 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

  3. Increased Access to Unrestricted Pharmacy Sales of Syringes in Seattle–King County, Washington: Structural and Individual-Level Changes, 1996 Versus 2003

    PubMed Central

    Deibert, Ryan J.; Goldbaum, Gary; Parker, Theodore R.; Hagan, Holly; Marks, Robert; Hanrahan, Michael; Thiede, Hanne

    2006-01-01

    We examined pharmacists’ attitudes and practices related to syringe sales to injection drug users before and after legal reform and local programming to enhance sterile syringe access. We replicated a 1996 study by conducting pharmacist phone surveys and syringe test-buys in randomly selected pharmacies. Test-buy success increased from 48% in 1996 to 65% in 2003 (P=.04). Pharmacists agreeing that syringes should be available to injection drug users through pharmacy purchase increased from 49% to 71% (P<.01). Pharmacy policies and pharmacist attitudes were strongly associated with syringe access. Structural changes, including policy reform and pharmacy outreach, appear to increase syringe access. Interventions should address pharmacy policies and pharmacist attitudes and policies. PMID:16809607

  4. ALTEA calibration

    NASA Astrophysics Data System (ADS)

    Zaconte, V.; Altea Team

    The ALTEA project is aimed at studying the possible functional damages to the Central Nervous System (CNS) due to particle radiation in space environment. The project is an international and multi-disciplinary collaboration. The ALTEA facility is an helmet-shaped device that will study concurrently the passage of cosmic radiation through the brain, the functional status of the visual system and the electrophysiological dynamics of the cortical activity. The basic instrumentation is composed by six active particle telescopes, one ElectroEncephaloGraph (EEG), a visual stimulator and a pushbutton. The telescopes are able to detect the passage of each particle measuring its energy, trajectory and released energy into the brain and identifying nuclear species. The EEG and the Visual Stimulator are able to measure the functional status of the visual system, the cortical electrophysiological activity, and to look for a correlation between incident particles, brain activity and Light Flash perceptions. These basic instruments can be used separately or in any combination, permitting several different experiments. ALTEA is scheduled to fly in the International Space Station (ISS) in November, 15th 2004. In this paper the calibration of the Flight Model of the silicon telescopes (Silicon Detector Units - SDUs) will be shown. These measures have been taken at the GSI heavy ion accelerator in Darmstadt. First calibration has been taken out in November 2003 on the SDU-FM1 using C nuclei at different energies: 100, 150, 400 and 600 Mev/n. We performed a complete beam scan of the SDU-FM1 to check functionality and homogeneity of all strips of silicon detector planes, for each beam energy we collected data to achieve good statistics and finally we put two different thickness of Aluminium and Plexiglas in front of the detector in order to study fragmentations. This test has been carried out with a Test Equipment to simulate the Digital Acquisition Unit (DAU). We are scheduled to

  5. Expanded syringe exchange programs and reduced HIV infection among new injection drug users in Tallinn, Estonia

    PubMed Central

    2011-01-01

    Background Estonia has experienced an HIV epidemic among intravenous drug users (IDUs) with the highest per capita HIV prevalence in Eastern Europe. We assessed the effects of expanded syringe exchange programs (SEP) in the capital city, Tallinn, which has an estimated 10,000 IDUs. Methods SEP implementation was monitored with data from the Estonian National Institute for Health Development. Respondent driven sampling (RDS) interview surveys with HIV testing were conducted in Tallinn in 2005, 2007 and 2009 (involving 350, 350 and 327 IDUs respectively). HIV incidence among new injectors (those injecting for < = 3 years) was estimated by assuming (1) new injectors were HIV seronegative when they began injecting, and (2) HIV infection occurred at the midpoint between first injection and time of interview. Results SEP increased from 230,000 syringes exchanged in 2005 to 440,000 in 2007 and 770,000 in 2009. In all three surveys, IDUs were predominantly male (80%), ethnic Russians (>80%), and young adults (mean ages 24 to 27 years). The proportion of new injectors decreased significantly over the years (from 21% in 2005 to 12% in 2009, p = 0.005). HIV prevalence among all respondents stabilized at slightly over 50% (54% in 2005, 55% in 2007, 51% in 2009), and decreased among new injectors (34% in 2005, 16% in 2009, p = 0.046). Estimated HIV incidence among new injectors decreased significantly from 18/100 person-years in 2005 and 21/100 person-years in 2007 to 9/100 person-years in 2009 (p = 0.026). Conclusions In Estonia, a transitional country, a decrease in the HIV prevalence among new injectors and in the numbers of people initiating injection drug use coincided with implementation of large-scale SEPs. Further reductions in HIV transmission among IDUs are still required. Provision of 70 or more syringes per IDU per year may be needed before significant reductions in HIV incidence occur. PMID:21718469

  6. "Single-use" needles and syringes for the prevention of HIV infection among injection drug users.

    PubMed

    Des Jarlais, D C

    1998-01-01

    Providing single-use injection equipment to persons who inject illicit drugs would appear to be an effective method for reducing HIV transmission. However, interviews with manufacturers, syringe exchange program staff, and drug users revealed numerous difficulties with such a technologic solution. All designs for such equipment can be defeated and should probably be called difficult-to-reuse equipment. There are problems with consumer acceptance of difficult-to-reuse equipment and with safe disposal of large amounts of biohazardous waste. Despite these problems, it would be useful to conduct additional research, particularly on the potential for placing difficult-to-reuse equipment into shooting galleries. PMID:9663624

  7. The use of syringe drivers in the community: considerations for palliative care providers.

    PubMed

    West, Cathy

    2014-02-01

    'Caring for him at home was such a sad, challenging but rewarding and special time ... we wouldn't have wanted him to die anywhere else ... things improved after the syringe driver was started as he seemed more at ease and was not suffering anymore ... the twinkle returned to his eyes for a while ... it made such a positive difference and allowed us to carry on at home until the end.' These words from the family of a dying patient recently cared for by the author remind us of how special the care given at the end of life is. PMID:24577209

  8. Syringe distribution to injection drug users for prevention of HIV infection: opinions and practices of health care providers in New York City.

    PubMed

    Coffin, Phillip O; Fuller, Crystal; Blaney, Shannon; Vadnai, Liza; Miller, Sarah; Vlahov, David

    2004-02-01

    The Expanded Syringe Access Demonstration Program (ESAP), which was intended to increase access to syringes for injection drug users (IDUs), went into effect in New York State on 1 January 2001. ESAP allowed prescription-authorized health care providers to register to distribute syringes without a prescription. In spring 2002, we conducted a random postal survey of 1100 providers in New York City to evaluate involvement in ESAP and willingness to furnish IDUs with syringes. Among 363 nurse practitioners, physicians, and physician assistants responding, 16.9% knew about ESAP, and 2.0% believed they were registered; 50.5% would consider distributing syringes to patients who were IDUs. Most of those unwilling to distribute syringes were concerned about legal and moral issues. More respondents agreed that providers should prescribe syringes than distribute syringes (41.1% vs. 22.7%; P<.0001). These results suggest that many providers are willing to furnish IDUs with syringes but are unaware of the current law. PMID:14727219

  9. 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.

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

    PubMed Central

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

    2012-01-01

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

  11. 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

  12. 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 μg/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 < 0.001). While 31.4-50.8% higher levels of Pb were observed in referents chewing different SLT products as compared to nonconsumers (p < 0.01). PMID:25903188

  13. Moving beyond non-engagement on regulated needle-syringe exchange programs in Australian prisons

    PubMed Central

    Mogg, Daniel; Levy, Michael

    2009-01-01

    Background Australia is at a fork in the road with the possibility of a needle-syringe exchange program (NSP) to be introduced at the new prison in the ACT. However, the current situation is characterised by non-engagement from major stakeholders. We explore why informed discussion will not be enough to convince prison officers, policy makers and the wider community of the benefits of prison-based NSPs. Other methods of engagement and communication will be proposed – in that may provide avenues for "breakthrough". Methods A review of the literature on needle-syringe exchanges and harm reduction strategies within the context of prisons and prisoner health was conducted. Literature on strategies to change attitudes and move beyond intractable situations was also consulted. In addition, one author, DM, conducted a two-hour interview with an ex-prison officer. Results No studies were found which investigated the potential efficacy of interventions to modify attitudes or behaviours in the specific context of introducing an NSP into a prison. Nonetheless, several theories were identified which may explain the failure of informed discussion alone to create change in this situation and may therefore lead to suggestions for engagement and communication to move towards a resolution Discussion Cognitive-behavioural therapy highlights the importance of individual cognitions and how they shape behaviours in any change campaign. Social identity theory emphasizes changes to social processes that may open the prison officer workforce to change. Peace studies also suggests socialization strategies such as observing an established and effective prison-based needle-syringe exchange. Social marketing provides suggestions on how to sell an exchange to ensuring the benefits are framed to outweigh the costs. Conclusion Psychology, peace studies and social marketing all agree people's views must be carefully collected and analysed if people are going to be convinced to consider and

  14. 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 0.005-2.4 µg g(-1) for desmetryn, atrazine and terbumeton, and 0.005-1.5 µg g(-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 0.09-0.39 ng g(-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

  15. Virtual camera calibration using optical design software.

    PubMed

    Poulin-Girard, Anne-Sophie; Dallaire, Xavier; Thibault, Simon; Laurendeau, Denis

    2014-05-01

    Camera calibration is a critical step in many vision applications. It is a delicate and complex process that is highly sensitive to environmental conditions. This paper presents a novel virtual calibration technique that can be used to study the impact of various factors on the calibration parameters. To highlight the possibilities of the method, the calibration parameters' behavior has been studied regarding the effects of tolerancing and temperature for a specific lens. This technique could also be used in many other promising areas to make calibration in the laboratory or in the field easier. PMID:24921866

  16. 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

  17. 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

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

    PubMed Central

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

    2011-01-01

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

  19. 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

  20. Non-stick syringe needles: Beneficial effects of thin film metallic glass coating

    PubMed Central

    Chu, Jinn P.; Yu, Chia-Chi; Tanatsugu, Yusuke; Yasuzawa, Mikito; Shen, Yu-Lin

    2016-01-01

    This paper reports on the use of Zr-based (Zr53Cu33Al9Ta5) thin film metallic glass (TFMG) for the coating of syringe needles and compares the results with those obtained using titanium nitride and pure titanium coatings. TFMG coatings were shown to reduce insertion forces by ∼66% and retraction forces by ∼72%, when tested using polyurethane rubber block. The benefits of TFMG-coated needles were also observed when tested using muscle tissue from pigs. In nano-scratch tests, the TFMG coatings achieved a coefficient of friction (COF) of just ∼0.05, which is about one order of magnitude lower than those of other coatings. Finite-element modeling also indicates a significant reduction in injection and retraction forces. The COF can be attributed to the absence of grain boundaries in the TFMG coating as well as a smooth surface morphology and low surface free energy. PMID:27573062

  1. [Exchange of syringes or apprenticeship? The buses of Bienne and Geneva].

    PubMed

    Malatesta, D; Joye, D; Kübler, D; Hausser, D

    1996-01-01

    In Switzerland, the health ministry (Office Fédéral de la Santé Publique) has systematically encouraged the evaluation of low threshold services. In this article, we discuss the evaluation of two of these: the buses for syringes exchange in Geneva and Bienne, the implementation of these two services, the success obtained and the contacts established. Even if the design of such an evaluation was relatively complicated, with one monitoring and two specific surveys, the principal aim of this article is not to measure the efficacy as such but to show how an learning process has occurred between the actors: government, administration, police, service's team, drug's users and neighbourhood's inhabitants. The efficacy for a long period of time and the implementation's success are largely linked to such learning processes. PMID:8693813

  2. Subtle clues to the diagnosis of the herpesvirus by light microscopy. Herpetic syringitis.

    PubMed

    Sangueza, O P; Gordon, M D; White, C R

    1995-04-01

    Among the numerous infections to which AIDS patients are susceptible, those caused by herpesvirus (simplex and varicella/zoster) are among the most common. Because herpetic infections may be the first manifestations of AIDS and often are associated with poor prognosis, rapid and accurate diagnosis of them is imperative. Herpesvirus infection may be diagnosed histopathologically by the presence of ballooned, acantholytic, and multinucleated keratinocytes; intranuclear eosinophilic viral inclusions; steel gray color of affected keratinocytic cytoplasm and nuclei, chromatin margination, and necrotic acantholytic keratinocytes in older lesions. These changes are often limited to the epidermis, but there may frequently be involvement of epithelia of follicles (herpetic folliculitis) and sebaceous glands as well. Similar changes, although seldom noted, may be present in eccrine ducts and glands (herpetic syringitis). Recognition of subtle histologic clues concerning the secretory and ductal components of sweat glands in an unusual case of herpes infection facilitated rapid diagnosis in an AIDS patient, allowing appropriate treatment. PMID:8600782

  3. Chemical stability and adsorption of succinylcholine chloride injections in disposable plastic syringes.

    PubMed

    Pramar, Y V; Moniz, D; Hobbs, D

    1994-06-01

    The purpose of these investigations was to determine the stability and adsorption behaviour of succinylcholine chloride (SCC) when stored in plastic syringes. Drug degradation was monitored using the USP high-pressure liquid chromatography method. Solutions containing 20 mg/ml of SCC in 5% dextrose, and in normal saline, were studied at 5, 25 and 40 degrees C. The hydrolysis of SCC in i.v. fluids followed apparent zero-order kinetics. The manufacturer's recommended expiry period was found to be too conservative. If protected from light, storage at room temperature for up to 3 months can be safely recommended, without significant loss of chemical stability. However, microbiological quality assurance will need to be implemented and an appropriate shelf-life assigned on the basis of both microbiological and chemical stability data. PMID:7962223

  4. Organizational Issues in the Implementation of a Hospital-Based Syringe Exchange Program

    PubMed Central

    Masson, Carmen L.; Sorensen, James L.; Grossman, Nina; Sporer, Karl A.; Des Jarlais, Don C.; Perlman, David C.

    2012-01-01

    Little published information exists to guide health care institutions in establishing syringe exchange program (SEP) services. To address this gap, this article discusses organizational issues encountered in the implementation of a hospital-based SEP in San Francisco, California (USA). Investigators collaborated with a community organization in implementing a county hospital-based SEP. SEP services integrated into a public hospital presented unique challenges directly related to their status as a health care institution. In the course of introducing SEP services into a hospital setting as part of a clinical trial, various ethical, legal, and logistical issues were raised. Based on these experiences, this paper provides guidance on how to integrate an SEP into a traditional health care institution. PMID:20397875

  5. Non-stick syringe needles: Beneficial effects of thin film metallic glass coating.

    PubMed

    Chu, Jinn P; Yu, Chia-Chi; Tanatsugu, Yusuke; Yasuzawa, Mikito; Shen, Yu-Lin

    2016-01-01

    This paper reports on the use of Zr-based (Zr53Cu33Al9Ta5) thin film metallic glass (TFMG) for the coating of syringe needles and compares the results with those obtained using titanium nitride and pure titanium coatings. TFMG coatings were shown to reduce insertion forces by ∼66% and retraction forces by ∼72%, when tested using polyurethane rubber block. The benefits of TFMG-coated needles were also observed when tested using muscle tissue from pigs. In nano-scratch tests, the TFMG coatings achieved a coefficient of friction (COF) of just ∼0.05, which is about one order of magnitude lower than those of other coatings. Finite-element modeling also indicates a significant reduction in injection and retraction forces. The COF can be attributed to the absence of grain boundaries in the TFMG coating as well as a smooth surface morphology and low surface free energy. PMID:27573062

  6. Calibration of sound calibrators: an overview

    NASA Astrophysics Data System (ADS)

    Milhomem, T. A. B.; Soares, Z. M. D.

    2016-07-01

    This paper presents an overview of calibration of sound calibrators. Initially, traditional calibration methods are presented. Following, the international standard IEC 60942 is discussed emphasizing parameters, target measurement uncertainty and criteria for conformance to the requirements of the standard. Last, Regional Metrology Organizations comparisons are summarized.

  7. Syringeable Pluronic-α-cyclodextrin supramolecular gels for sustained delivery of vancomycin.

    PubMed

    Simões, S M N; Veiga, F; Torres-Labandeira, J J; Ribeiro, A C F; Sandez-Macho, M I; Concheiro, A; Alvarez-Lorenzo, C

    2012-01-01

    The ability of Pluronic® F127 to form supramolecular gels in the presence of αCD has been explored as a way to design syringeable gel formulations able to sustain drug release while using the lowest proportion of both components. The effects of αCD concentration range (0-9.7% w/v) in copolymer (6.5%, 13% and 20%) gel features were evaluated at 4, 20 and 37°C. An effective complexation of Pluronic and αCD was evidenced as a change in the surface pressure of the π-A isotherm of Pluronic on a subphase of CD solution and the apparition of new peaks in the X-ray spectra. Once the Pluronic and αCD solutions were mixed, the systems became progressively turbid solutions or white gels. The greater the αCD concentration was, the faster the gel formation. The supramolecular hydrogels were thixotropic and those containing 5% or more αCD had G' values above G″ at room temperature, but they were still easily syringeable. The values of both moduli increased as temperature raised; the effect being more evident for 13% and 20% w/v copolymer. The gels prepared with low proportions of αCD exhibited phase separation in few days, particularly when stored at 4 or 37 °C. By contrast, those prepared with 6.5% copolymer were stable for at least two months when stored at 20 °C. The gels were able to sustain vancomycin release for several days; the higher the αCD proportion, the slower the release was. Furthermore, the drug-loaded gels showed activity against Staphylococcus aureus. The results obtained highlight the role of the αCD concentration on the tuning of the rheological features and drug release profiles from Pluronic gels. PMID:22005155

  8. 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 μm 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

  9. 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

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

    PubMed

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

    2009-05-13

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

  11. A syringe-like love dart injects male accessory gland products in a tropical hermaphrodite.

    PubMed

    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

  12. Evaluation of Incremental Siliconization Levels on Soluble Aggregates, Submicron and Subvisible Particles in a Prefilled Syringe Product.

    PubMed

    Bai, Shujun; Landsman, Pavel; Spencer, Andrea; DeCollibus, Daniel; Vega, Fabian; Temel, Deniz B; Houde, Damian; Henderson, Olivia; Brader, Mark L

    2016-01-01

    The evaluation of stability with respect to particles in prefilled syringes is complicated by the presence of silicone oil. The mobility, colloidal characteristics, and kinetic instability of silicone oil in contact with a protein formulation may be influenced in unpredictable ways by pharmaceutical variables, storage, and handling conditions. To provide insight into the impact of these variables on silicone oil originating specifically from the siliconized prefillable syringe (PFS), a series of studies were conducted at incremental syringe barrel siliconization levels. Size-exclusion chromatography and particle counting methods were used to quantitate soluble aggregates and submicron and subvisible particles in peginterferon beta-1a in a PFS siliconized with a fixed nozzle spray-on siliconization process. The effect of silicone oil on the peginterferon beta-1a molecule was examined under pharmaceutically relevant conditions, accelerated degradation, and under denaturing conditions. Resonant mass measurement was used to discriminate silicone oil from protein particles establishing that silicone oil does not mask adverse trends in non-silicone oil particles. The peginterferon beta-1a molecule was shown to be stable in the presence of silicone oil and robust with respect to the formation of soluble aggregates and submicron and subvisible particles in its PFS siliconized over the range of 0-1.2 mg silicone oil per syringe barrel. PMID:26852839

  13. Three-dimensional Quantitative Porosity Characterization of Syringe- versus Hand-mixed Set Epoxy Resin Root Canal Sealer.

    PubMed

    De-Deus, Gustavo; Scelza, Miriam Z; Neelakantan, Prasanna; Sharma, Subash; Neves, Aline de Almeida; Silva, Emmanuel João Nogueira Leal

    2015-01-01

    The aim of the present study was to compare the porosity characteristics of AH Plus Jet(tm) syringe-mix and the conventional hand-mixed AH Plus root canal sealers by three-dimensional quantitative high-resolution micro-computed tomography (micro-CT). Seven test specimens were prepared from each tested sealer by a single operator following the manufacturer's instructions and poured into pre-lubricated plastic split-ring moulds. Set sealer test specimens were scanned using a micro-CT device and the shadow images were reconstructed into cross-sectional slices. The evaluated parameters were (i) total pore count, (ii) total pore volume and mean pore volume, (iii) total porosity (% of pore volume in relation to total sealer volume) and (iv) mean pore distance to the sealer lateral external surface. In both groups, most pores were localized within the external sealer perimeter (0.05 mm from the external surface). Hand-mixed AH Plus specimens showed statistically significant higher mean total pore count, total pore volume and total porosity (p=0.001) than the syringe-mixed specimens. However, mean pore sizes in AH Plus syringe-mixed specimens were significantly higher (p=0.046) than the AH Plus hand-mixed counterparts. Hand-mixed AH Plus was associated with higher total mean pore count, volume and total porosity compared to syringe mixed AH Plus. PMID:26963204

  14. 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 0.86 ng L(-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

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

    NASA Astrophysics Data System (ADS)

    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 0.86 ng L- 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.

  16. Effervescence-assisted β-cyclodextrin/attapulgite composite for the in-syringe dispersive solid-phase extraction of pyrethroids in environmental water samples.

    PubMed

    Yang, Xiaoling; Zhang, Panjie; Li, Xiaobing; Hu, Lu; Gao, Haixiang; Zhang, Sanbing; Zhou, Wenfeng; Lu, Runhua

    2016-06-01

    In this research, an effervescence-assisted β-cyclodextrin/attapulgite composite (β-CD/ATP) for the in-syringe dispersive solid-phase extraction (EAIS-DSPE) of pyrethroids in environmental samples was developed for the first time. A syringe was used to conduct the extraction procedure and a small amount of β-CD/ATP was dispersed into the solution with the release of carbon dioxide when the effervescent tablet components dissolved in water. Then, the sorbent was recovered using a filter membrane, and the analytes were directly eluted using acetonitrile. In the process, the β-CD/ATP sorbent resulted in an excellent extraction efficiency compared to commercially available sorbents such as C18 and HLB. Moreover, in the extraction procedure, both the β-cyclodextrin inclusion interactions (especially the hydrophobic effects) and the special structure of the ATP contributed to the efficient enrichment of pyrethroids in aqueous media. The amount of β-CD/ATP sorbent, the volume of desorption, the ratio of NaH2PO4/Na2CO3, the volume of the sample, and the pH were screened using a Plackett-Burman design. All factors affecting the procedure were optimized by applying a central composite design. Under the optimized conditions, a good repeatability (RSDs) ranging from 1.7 to 2.3, linearity (2.5-500μgL(-1)), limits of detection (LODs) (0.15-1.03μgL(-1)), and an acceptable recoveries (76.8-86.5%) were achieved. Finally, the proposed method was successfully applied for the determination of pyrethroids in environmental samples including river water, reservoir water and lake water. PMID:27130127

  17. The Evidence Does Not Speak for Itself: The Role of Research Evidence in Shaping Policy Change for the Implementation of Publicly Funded Syringe Exchange Programs in Three US Cities

    PubMed Central

    Allen, Sean T.; Ruiz, Monica S.; O’Rourke, Allison

    2015-01-01

    Background A breadth of literature exists that explores the utilization of research evidence in policy change processes. From this work, a number of studies suggest research evidence is applied to change processes by policy change stakeholders primarily through instrumental, conceptual, and/or symbolic applications, or is not used at all. Despite the expansiveness of research on policy change processes, a deficit exists in understanding the role of research evidence during change processes related to the implementation of structural interventions for HIV prevention among injection drug users (IDU). This study examined the role of research evidence in policy change processes for the implementation of publicly funded syringe exchange services in three US cities: Baltimore, MD, Philadelphia, PA, and Washington, DC. Methods In-depth qualitative interviews were conducted with key stakeholders (N=29) from each of the study cities. Stakeholders were asked about the historical, social, political, and scientific contexts in their city during the policy change process. Interviews were transcribed and analyzed for common themes pertaining to applications of research evidence. Results In Baltimore and Philadelphia, the typological approaches (instrumental and symbolic/conceptual, respectively) to the applications of research evidence used by harm reduction proponents contributed to the momentum for securing policy change for the implementation of syringe exchange services. Applications of research evidence were less successful in DC because policymakers had differing ideas about the implications of syringe exchange program implementation and because opponents of policy change used evidence incorrectly or not at all in policy change discussions. Conclusion Typological applications of research evidence are useful for understanding policy change processes, but their efficacy falls short when sociopolitical factors complicate legislative processes. Advocates for harm reduction may

  18. Absolute calibration in vivo measurement systems

    SciTech Connect

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

    1991-02-01

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

  19. A novel approach to Lab-In-Syringe Head-Space Single-Drop Microextraction and on-drop sensing of ammonia.

    PubMed

    Šrámková, Ivana; Horstkotte, Burkhard; Sklenářová, Hana; Solich, Petr; Kolev, Spas D

    2016-08-31

    A novel approach to the automation technique Lab-In-Syringe, also known as In-Syringe Analysis, is proposed which utilizes a secondary inlet into the syringe void, used as a size-adaptable reaction chamber, via a channel passing through the syringe piston. This innovative approach allows straightforward automation of head-space single-drop microextraction, involving accurately controlled drop formation and handling, and the possibility of on-drop analyte quantification. The syringe was used in upside-down orientation and in-syringe magnetic stirring was carried out, which allowed homogenous mixing of solutions, promotion of head-space analyte enrichment, and efficient syringe cleaning. The superior performance of the newly developed system was illustrated with the development of a sensitive method for total ammonia determination in surface waters. It is based on head-space extraction of ammonia into a single drop of bromothymol blue indicator created inside the syringe at the orifice of the syringe piston channel and on-drop sensing of the color change via fiber optics. The slope of the linear relationship between absorbance and time was used as the analytical signal. Drop formation and performance of on-drop monitoring was further studied with rhodamine B solution to give a better understanding of the system's performance. A repeatability of 6% RSD at 10 μmol L(-1) NH3, a linear range of up to 25 μmol L(-1) NH3, and a limit of detection of 1.8 μmol L(-1) NH3 were achieved. Study of interferences proved the high robustness of the method towards humic acids, high sample salinity, and the presence of detergents, thus demonstrating the method superiority compared to the state-of-the-art gas-diffusion methods. A mean analyte recovery of 101.8% was found in analyzing spiked environmental water samples. PMID:27506353

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

    SciTech Connect

    Giles, J.R.

    1996-05-01

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

  1. 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

  2. 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.

  3. Evaluation of expanded uncertainties in luminous intensity and illuminance calibrations

    SciTech Connect

    Sametoglu, Ferhat

    2008-11-01

    Detector-based calibrating methods and expressions for calculation of photometric uncertainties related to uncertainties in the calibrations of luminous intensity of a light source, illuminance responsivity of a photometer head, and calibration factors of an illuminance meter are discussed. These methods permit luminous intensity calibrations of incandescent light sources, luminous responsivity calibrations of photometer heads, and calibration factors of illuminance meters to be carried out with relative expanded uncertainties (with a level of confidence of 95.45%) of 0.4%, 0.4%, and 0.6%, respectively.

  4. Improving self-calibration

    NASA Astrophysics Data System (ADS)

    Enßlin, Torsten A.; Junklewitz, Henrik; Winderling, Lars; Greiner, Maksim; Selig, Marco

    2014-10-01

    Response calibration is the process of inferring how much the measured data depend on the signal one is interested in. It is essential for any quantitative signal estimation on the basis of the data. Here, we investigate self-calibration methods for linear signal measurements and linear dependence of the response on the calibration parameters. The common practice is to augment an external calibration solution using a known reference signal with an internal calibration on the unknown measurement signal itself. Contemporary self-calibration schemes try to find a self-consistent solution for signal and calibration by exploiting redundancies in the measurements. This can be understood in terms of maximizing the joint probability of signal and calibration. However, the full uncertainty structure of this joint probability around its maximum is thereby not taken into account by these schemes. Therefore, better schemes, in sense of minimal square error, can be designed by accounting for asymmetries in the uncertainty of signal and calibration. We argue that at least a systematic correction of the common self-calibration scheme should be applied in many measurement situations in order to properly treat uncertainties of the signal on which one calibrates. Otherwise, the calibration solutions suffer from a systematic bias, which consequently distorts the signal reconstruction. Furthermore, we argue that nonparametric, signal-to-noise filtered calibration should provide more accurate reconstructions than the common bin averages and provide a new, improved self-calibration scheme. We illustrate our findings with a simplistic numerical example.

  5. 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 μg L(-1) (S=53.7+2.61C, in which S is the net fluorescence and C is iodide concentration in μg L(-1)). Detection limit, coefficient of variation (n=6) and sampling rate were estimated at 0.3 μg L(-1), 0.8% and 20 h(-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

  6. Systematic evaluation of dissolved lead sorption losses to particulate syringe filter materials.

    PubMed

    Minning, Thomas; Lytle, Darren A; Pham, Maily; Kelty, Keith

    2015-06-01

    Distinguishing between soluble and particulate lead in drinking water is useful in understanding the mechanism of lead release and identifying remedial action. Typically, particulate lead is defined as the amount of lead removed by a 0.45-μm filter. Unfortunately, there is little guidance regarding selection of filter membrane material and little consideration to the possibility of the sorption of dissolved lead to the filter. The objective of this work was to examine the tendency of 0.45-μm syringe filter materials to adsorb lead. Tests were performed with water containing 40 and 24 μg/L soluble lead at pH 7 buffered with 50 mg C/L dissolved inorganic concentration (DIC). The amounts of lead sorbed greatly varied by filter, and only two filter types, polypropylene and mixed cellulose esters, performed well and are recommended. Great care must be taken in choosing a filter when filtering soluble lead and interpreting filter results. PMID:26017807

  7. Assessing Syringe Exchange Program Access among Persons Who Inject Drugs (PWID) in the District of Columbia.

    PubMed

    Allen, Sean T; Ruiz, Monica S; Jones, Jeff

    2016-02-01

    Prior research has explored spatial access to syringe exchange programs (SEPs) among persons who inject drugs (PWID), but these studies have been based on limited data from short periods of time. No research has explored changes in spatial access to SEPs among PWID longitudinally. The purpose of this research is to examine spatial access to SEPs among PWID who accessed services at a SEP in Washington, District of Columbia (DC), from 1996 to 2010. The geometric point distance estimation technique was used to calculate the mean walking distance PWID traveled from the centroid point of their zip code of home residence to the mobile exchange site where they accessed SEP services. Analysis of variance (ANOVA) was used to examine differences in walking distance measures by year. The results of this research suggest that the distance DC PWID traveled to access SEP services remained relatively constant (approximately 2.75 mi) from 2003 to 2008, but increased to just over 4 mi in 2010. This research provides support for expanding SEP operations such that PWID have increased access to their services. Increasing SEP accessibility may help resolve unmet needs among injectors. PMID:26786782

  8. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2010-04-01

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

  12. Syringe-cartridge solid-phase extraction method for patulin in apple juice.

    PubMed

    Eisele, Thomas A; Gibson, Midori Z

    2003-01-01

    A syringe-cartridge solid-phase extraction (SPE) method was developed for determination of patulin in apple juice. A 2.5 mL portion of test sample was passed through a conditioned macroporous SPE cartridge and washed with 2 mL 1% sodium bicarbonate followed by 2 mL 1% acetic acid. Patulin was eluted with 1 mL 10% ethyl acetate in ethyl ether and determined by reversed-phase liquid chromatography using a mobile phase consisting of 81% acetonitrile, 9% water, and 10% 0.05M potassium phosphate buffer, pH 2.4. Recoveries averaged 92% and the relative standard deviation was 8.0% in test samples spiked with 50 ng/mL patulin. The method appears to be applicable for monitoring apple juice samples to meet the U.S. Food and Drug Administration compliance action level of 50 microg/kg in an industrial quality assurance laboratory environment. PMID:14979697

  13. Protective effect of syringic acid on kidney ischemia-reperfusion injury.

    PubMed

    Sancak, Eyup Burak; Akbas, Alpaslan; Silan, Coskun; Cakir, Dilek Ulker; Turkon, Hakan; Ozkanli, Sidika Seyma

    2016-05-01

    The objective of the present study was to determine whether preischemic administration of syringic acid (SA) would attenuate renal ischemia-reperfusion injury (IRI). Rats were divided into three groups: Sham group; IR group; and IR + SA group. The effects of SA were examined using biochemical parameters including serum ischemia-modified albumin (IMA), total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), tissue superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and malondialdehyde (MDA). The apoptosis status and histopathological changes were evaluated. After calculating the score for each histopathological change, the total score was obtained by summing all the scores. In the SA group, MDA, IMA, TOS, and OSI decreased significantly compared to the IR group. After SA administration, the increase in GPx activity was found to be significant. Apoptosis decreased significantly in the SA group compared with the IR group. The total score significantly decreased after administration of SA. Taken together, our findings suggest that SA preconditioning is effective in reducing tissue damage induced in kidney IRI. Renal histology also showed convincing evidence regarding the protective nature of SA. PMID:26915396

  14. Functional Evaluation and Characterization of a Newly Developed Silicone Oil-Free Prefillable Syringe System

    PubMed Central

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

    2014-01-01

    The functionality of a newly developed silicone oil-free (SOF) syringe system, of which the plunger stopper is coated by a novel coating technology (i-coating™), was assessed. By scanning electron microscopy observations and other analysis, it was confirmed that the plunger stopper surface was uniformly covered with the designed chemical composition. A microflow imaging analysis showed that the SOF system drastically reduced both silicone oil (SO) doplets and oil-induced aggregations in a model protein formulation, whereas a large number of subvisible particles and protein aggregations were formed when a SO system was used. Satisfactory container closure integrity (CCI) was confirmed by means of dye and microorganism penetration studies. Furthermore, no significant difference between the break loose and gliding forces was observed in the former, and stability studies revealed that the SOF system could perfectly show the aging independence in break loose force observed in the SO system. The results suggest that the introduced novel SOF system has a great potential and represents an alternative that can achieve very low subvisible particles, secure CCI, and the absence of a break loose force. In particular, no risk of SO-induced aggregation can bring additional value in the highly sensitive biotech drug market. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:1520–1528, 2014 PMID:24643749

  15. 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 μm 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 μm 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 μm, the optimally controlled delivery of liquid drug by the irradiated laser pulse is shown possible.

  16. A novel and innovative technique of using a disposable syringe and mesh for harvesting fat for structural fat grafting

    PubMed Central

    Ashok, B. C.; Nagaraj, Pradeep Kumar; Ananteshwar, Y. N.; Srikanth, V.

    2015-01-01

    Background: Successful restoration of structure and function using autologous free fat grafts has remained elusive. Review of literature shows that various harvesting and preparation techniques have been suggested. The goal of these techniques is to obtain greater adipocyte cell survival and consequently more reliable clinical results. Materials and Methods: In our technique, a piece of mesh is kept at one end of the lipoaspiration syringe, which is then connected to the Suction pump. As one syringe fills, it is replaced by another one until the required amount of fat is obtained. Results: By using a polypropylene mesh in our technique, we can separate the transfusate from the harvested fat graft during harvesting itself. The fat graft thus obtained is dense and concentrated, with fewer impurities. Conclusion: Hence, we recommend our technique as a reliable method for extracting sterile emulsified fat in an economical way. PMID:25991892

  17. 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.

  18. Dual HIV risk: receptive syringe sharing and unprotected sex among HIV-negative injection drug users in New York City.

    PubMed

    Neaigus, Alan; Reilly, Kathleen H; Jenness, Samuel M; Hagan, Holly; Wendel, Travis; Gelpi-Acosta, Camila

    2013-09-01

    HIV-negative injection drug users (IDUs) who engage in both receptive syringe sharing and unprotected sex ("dual HIV risk") are at high risk of HIV infection. In a cross-sectional study conducted in New York City in 2009, active IDUs aged ≥18 years were recruited using respondent-driven sampling, interviewed, and tested for HIV. Participants who tested HIV-negative and did not self-report as positive were analyzed (N = 439). Adjusted odds ratios (aOR) and 95 % confidence intervals (95 % CI) were estimated using multinomial logistic regression. The sample was: 77.7 % male; 54.4 % Hispanic, 36.9 % white, and 8.7 % African-American/black. Dual risk was engaged in by 26.2 %, receptive syringe sharing only by 3.2 %, unprotected sex only by 49.4 %, and neither by 21.2 %. Variables independently associated with engaging in dual risk versus neither included Hispanic ethnicity (vs. white) (aOR = 2.0, 95 % CI = 1.0-4.0), married or cohabiting (aOR = 6.3, 95 % CI = 2.5-15.9), homelessness (aOR = 3.4, 95 % CI = 1.6-7.1), ≥2 sex partners (aOR = 8.7, 95 % CI = 4.4-17.3), ≥2 injecting partners (aOR = 2.9, 95 % CI = 1.5-5.8), and using only sterile syringe sources (protective) (aOR = 0.5, 95 % CI = 0.2-0.9). A majority of IDUs engaged in HIV risk behaviors, and a quarter in dual risk. Interventions among IDUs should simultaneously promote the consistent use of sterile syringes and of condoms. PMID:23640654

  19. Calibration Methods for a 3D Triangulation Based Camera

    NASA Astrophysics Data System (ADS)

    Schulz, Ulrike; Böhnke, Kay

    A sensor in a camera takes a gray level image (1536 x 512 pixels), which is reflected by a reference body. The reference body is illuminated by a linear laser line. This gray level image can be used for a 3D calibration. The following paper describes how a calibration program calculates the calibration factors. The calibration factors serve to determine the size of an unknown reference body.

  20. 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.

  1. 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.

  2. 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 Central

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

    2015-01-01

    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

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

    PubMed Central

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

    2013-01-01

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

  4. 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.

  5. 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.

  6. 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.

  7. Evaluation of a new syringe presentation of reduced-antigen content diphtheria, tetanus, and acellular pertussis vaccine in healthy adolescents - A single blind randomized trial

    PubMed Central

    Pavia-Ruz, Noris; Abarca, Katia; Lepetic, Alejandro; Cervantes-Apolinar, Maria Yolanda; Hardt, Karin; Jayadeva, Girish; Kuriyakose, Sherine; Han, Htay Htay; de la O, Manuel

    2015-01-01

    Reduced-antigen-content diphtheria-tetanus-acellular pertussis (dTpa) vaccine, Boostrix™, is indicated for booster vaccination of children, adolescents and adults. The original prefilled disposable dTpa syringe presentation was recently replaced by another prefilled-syringe presentation with latex-free tip-caps and plunger-stoppers. 671 healthy adolescents aged 10–15 years who had previously received 5 or 6 previous DT(P)/dT(pa) vaccine doses, were randomized (1:1) to receive dTpa booster, injected using the new (dTpa-new) or previous syringe (dTpa-previous) presentations. Immunogenicity was assessed before and 1-month post-booster vaccination; safety/reactogenicity were assessed during 31-days post-vaccination. Non-inferiority of dTpa-new versus dTpa-previous was demonstrated for all antigens (ULs 95% CIs for GMC ratios ranged between 1.03-1.13). 1-month post-booster, immune responses were in similar ranges for all antigens with both syringe presentations. dTpa delivered using either syringe presentation was well-tolerated. These clinical results complement the technical data and support the use of the new syringe presentation to deliver the dTpa vaccine. PMID:26075317

  8. Evaluation of a new syringe presentation of reduced-antigen content diphtheria, tetanus, and acellular pertussis vaccine in healthy adolescents--A single blind randomized trial.

    PubMed

    Pavia-Ruz, Noris; Abarca, Katia; Lepetic, Alejandro; Cervantes-Apolinar, Maria Yolanda; Hardt, Karin; Jayadeva, Girish; Kuriyakose, Sherine; Han, Htay Htay; de la O, Manuel

    2015-01-01

    Reduced-antigen-content diphtheria-tetanus-acellular pertussis (dTpa) vaccine, Boostrix™, is indicated for booster vaccination of children, adolescents and adults. The original prefilled disposable dTpa syringe presentation was recently replaced by another prefilled-syringe presentation with latex-free tip-caps and plunger-stoppers. 671 healthy adolescents aged 10-15 years who had previously received 5 or 6 previous DT(P)/dT(pa) vaccine doses, were randomized (1:1) to receive dTpa booster, injected using the new (dTpa-new) or previous syringe (dTpa-previous) presentations. Immunogenicity was assessed before and 1-month post-booster vaccination; safety/reactogenicity were assessed during 31-days post-vaccination. Non-inferiority of dTpa-new versus dTpa-previous was demonstrated for all antigens (ULs 95% CIs for GMC ratios ranged between 1.03-1.13). 1-month post-booster, immune responses were in similar ranges for all antigens with both syringe presentations. dTpa delivered using either syringe presentation was well-tolerated. These clinical results complement the technical data and support the use of the new syringe presentation to deliver the dTpa vaccine. PMID:26075317

  9. 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 500μL of sample through a C18 sorbent in a MEPS syringe placed in the semi-automatic eVol(®) syringe followed by elution using 250μL 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

  10. Calibration system for albedo neutron dosimeters

    SciTech Connect

    Rothermich, N.E.

    1981-01-01

    Albedo neutron dosimeters have proven to be effective as a method of measuring the dose from neutron exposures that other types of neutron detectors cannot measure. Results of research conducted to calibrate an albedo neutron dosemeter are presented. The calibration procedure consisted of exposing the TLD chips to a 46 curie /sup 238/PuBe source at known distances, dose rates and exposure periods. The response of the TLD's is related to the dose rate measured with a dose rate meter to obtain the calibration factor. This calibration factor is then related to the ratio of the counting rates determined by 9-inch and 3-inch Bonner spheres (also called remmeters) and a calibration curve was determined. 17 references, 10 figures, 3 tables.

  11. Miniaturized ionic liquid dispersive liquid-liquid microextraction in a coupled-syringe system combined with UV for extraction and determination of danazol in danazol capsule and mice serum

    NASA Astrophysics Data System (ADS)

    Gong, Aiqin; Zhu, Xiashi

    2016-04-01

    In this study, for the first time, a coupled 1-mL microsyringe system was utilized to perform a miniaturized ionic liquid dispersive liquid-liquid microextraction (IL-DLLME) method. Danazol was extracted and determined via the developed method followed by micro-volume ultraviolet spectroscopy (UV). The extraction process was carried out by the injection of extraction solvent ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate [C8mimPF6] into sample solution (syringe A), and then rapid shoot the solution into syringe B. After that the shooting was repeated several times at a rate of 1 cycle/s. The extraction procedure was induced by the formation of cloudy solution, which was composed of fine drops of [C8mimPF6] dispersed entirely into sample solution with the help of shooting without any dispersive solvent, ultrasonication or high temperature. Several important parameters affecting the extraction efficiency were studied and optimized. Under the optimized conditions, the limit of detection (LOD) was 0.055 μg/mL (capsule) or 0.054 μg/mL (serum) at a signal-to-noise ratio of 3. The calibration curve was linear over the range of 0.62-25 μg/mL. The proposed method was successfully applied to danazol capsule and the real mice serum samples and good spiked recoveries in the range of 90.5-103.4% were obtained. The obtained results of this work were in good agreement with the results of HPLC.

  12. Miniaturized ionic liquid dispersive liquid-liquid microextraction in a coupled-syringe system combined with UV for extraction and determination of danazol in danazol capsule and mice serum.

    PubMed

    Gong, Aiqin; Zhu, Xiashi

    2016-04-15

    In this study, for the first time, a coupled 1-mL microsyringe system was utilized to perform a miniaturized ionic liquid dispersive liquid-liquid microextraction (IL-DLLME) method. Danazol was extracted and determined via the developed method followed by micro-volume ultraviolet spectroscopy (UV). The extraction process was carried out by the injection of extraction solvent ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate [C8mimPF6] into sample solution (syringe A), and then rapid shoot the solution into syringe B. After that the shooting was repeated several times at a rate of 1 cycle/s. The extraction procedure was induced by the formation of cloudy solution, which was composed of fine drops of [C8mimPF6] dispersed entirely into sample solution with the help of shooting without any dispersive solvent, ultrasonication or high temperature. Several important parameters affecting the extraction efficiency were studied and optimized. Under the optimized conditions, the limit of detection (LOD) was 0.055 μg/mL (capsule) or 0.054 μg/mL (serum) at a signal-to-noise ratio of 3. The calibration curve was linear over the range of 0.62-25 μg/mL. The proposed method was successfully applied to danazol capsule and the real mice serum samples and good spiked recoveries in the range of 90.5-103.4% were obtained. The obtained results of this work were in good agreement with the results of HPLC. PMID:26845583

  13. 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 50 µg L(-1), described by the equation A=0.137+0.050C(Sb) (r=0.998). The detection limit (99.7% confidence level), the coefficient of variation (n=5; 15 µg L(-1)) and the sampling rate was estimated at 1.8 µg L(-1), 1.6% and 16 h(-1), respectively. The procedure allows quantification of antimony in the concentrations established by environmental legislation (6 µg L(-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

  14. Improving Viability of Stem Cells During Syringe Needle Flow Through the Design of Hydrogel Cell Carriers

    PubMed Central

    Aguado, Brian A.; Mulyasasmita, Widya; Su, James; Lampe, Kyle J.

    2012-01-01

    Cell transplantation is a promising therapy for a myriad of debilitating diseases; however, current delivery protocols using direct injection result in poor cell viability. We demonstrate that during the actual cell injection process, mechanical membrane disruption results in significant acute loss of viability at clinically relevant injection rates. As a strategy to protect cells from these damaging forces, we hypothesize that cell encapsulation within hydrogels of specific mechanical properties will significantly improve viability. We use a controlled in vitro model of cell injection to demonstrate success of this acute protection strategy for a wide range of cell types including human umbilical vein endothelial cells (HUVEC), human adipose stem cells, rat mesenchymal stem cells, and mouse neural progenitor cells. Specifically, alginate hydrogels with plateau storage moduli (G′) ranging from 0.33 to 58.1 Pa were studied. A compliant crosslinked alginate hydrogel (G′=29.6 Pa) yielded the highest HUVEC viability, 88.9%±5.0%, while Newtonian solutions (i.e., buffer only) resulted in 58.7%±8.1% viability. Either increasing or decreasing the hydrogel storage modulus reduced this protective effect. Further, cells within noncrosslinked alginate solutions had viabilities lower than media alone, demonstrating that the protective effects are specifically a result of mechanical gelation and not the biochemistry of alginate. Experimental and theoretical data suggest that extensional flow at the entrance of the syringe needle is the main cause of acute cell death. These results provide mechanistic insight into the role of mechanical forces during cell delivery and support the use of protective hydrogels in future clinical stem cell injection studies. PMID:22011213

  15. Housing instability among people who inject drugs: results from the Australian needle and syringe program survey.

    PubMed

    Topp, Libby; Iversen, Jenny; Baldry, Eileen; Maher, Lisa

    2013-08-01

    High rates of substance dependence are consistently documented among homeless people, and are associated with a broad range of negative outcomes among this population. Investigations of homelessness among drug users are less readily available. This study examined the prevalence and correlates of housing instability among clients of needle syringe programs (NSPs) via the Australian NSP Survey, annual cross-sectional seroprevalence studies among NSP attendees. Following self-completion of a brief, anonymous survey and provision of a capillary blood sample by 2,396 NSP clients, multivariate logistic regressions identified the variables independently associated with housing instability. Nineteen percent of ANSPS participants reported current unstable housing, with primary ('sleeping rough'; 5 %), secondary (staying with friends/relatives or in specialist homelessness services; 8 %), and tertiary (residential arrangements involving neither secure lease nor private facilities; 6 %) homelessness all evident. Extensive histories of housing instability were apparent among the sample: 66 % reported at least one period of sleeping rough, while 77 % had shifted between friends/relatives (73 %) and/or resided in crisis accommodation (52 %). Participants with a history of homelessness had cycled in and out of homelessness over an average of 10 years; and one third reported first being homeless before age 15. Compared to their stably housed counterparts, unstably housed participants were younger, more likely to be male, of Indigenous Australian descent, and to report previous incarceration; they also reported higher rates of key risk behaviors including public injecting and receptive sharing of injecting equipment. The high prevalence of both historical and current housing instability among this group, particularly when considered in the light of other research documenting the many adverse outcomes associated with this particular form of disadvantage, highlights the need

  16. Orbital Acceleration Research Experiment: Calibration Measurements

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

    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 10(sub -9) 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, and thus provides 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 are also presented. Estimates on calibration uncertainties are discussed. These uncertainty estimates provides bounds on the STS-58 absolute acceleration measurements for future applications.

  17. 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.

  18. Flight calibration assessment of HiRAP accelerometer data

    NASA Technical Reports Server (NTRS)

    Blanchard, Robert C.; Larman, Kevin T.; Moast, Christina D.

    1993-01-01

    A flight derived method of calibrating the High Resolution Accelerometer Package (HiRAP) flight data has been developed and is discussed for Shuttle Orbiter missions STS-35 and STS-40. These two mission data sets have been analyzed using ground calibration factors and flight derived calibration factors. This flight technique evolved early in the flight program when it was recognized that ground calibration factors are insufficient to determine absolute low-acceleration levels. The application of flight calibration factors to the data sets from these missions produced calibrated acceleration levels within an accuracy of less than +/- 1.5 microgravity of zero during a time in the flight when the acceleration level was known to be less than 1.0 microgravity. This analysis further confirms the theory that flight calibrations are required in order to obtain the absolute measurement of low-frequency, low-acceleration flight signals.

  19. Pharmacist and pharmacy staff experiences with non-prescription (NP) sale of syringes and attitudes toward providing HIV prevention services for injection drug users (IDUs) in Providence, RI.

    PubMed

    Zaller, Nickolas; Jeronimo, Alexandra; Bratberg, Jeffrey; Case, Patricia; Rich, Josiah D

    2010-12-01

    Increased access to sterile syringes among injection drug users (IDUs) has been correlated with reduced syringe sharing. Many states, including Rhode Island, have legalized non-prescription (NP) sale of syringes in pharmacies. Previous studies have suggested that training pharmacists to provide HIV-related services to IDUs may be an important opportunity to engage IDUs and provide them with such services. However, it is not clear to what extent pharmacy staff are willing to expand their roles in providing services to IDUs who come in to purchase syringes. We recruited pharmacists and pharmacy staff from the 48 pharmacies indicating NP sale of syringes in the greater Providence, RI area, to participate in an online survey consisting of demographic information; views about the current syringe laws in Rhode Island; willingness to provide HIV-related services, including referral for HIV testing, substance use treatment, and medical and social services, to IDUs; and past experiences with IDU customers. One hundred and forty-six individuals completed the online survey (32 pharmacies, 114 pharmacy staff). Most participants were employed by chain pharmacies (92%). Most participants thought that pharmacies are important resources for IDU customers (77%) and that they would be willing to provide health and prevention information/referrals to IDU customers who purchase NP syringes (59%). With respect to willingness to offer HIV prevention-related services, access to confidential space and concern about personal safety had the strongest associations with willingness to provide HIV prevention services (OR, 4.3 and 0.1, respectively). As the nature of the retail pharmacy shifts, researchers, pharmacy executives, and health care officials can build upon the willingness of pharmacists and pharmacy staff in order to address the health needs of injection drug users and other underserved populations. PMID:21116724

  20. Assessment of MODIS Reflected Solar Calibration Uncertainty

    NASA Technical Reports Server (NTRS)

    Xiong, Xiaoxiong; Sun, Junqiang; Butler, James

    2011-01-01

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

  1. Nonlinear Observers for Gyro Calibration

    NASA Technical Reports Server (NTRS)

    Thienel, Julie; Sanner, Robert M.

    2003-01-01

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

  2. When calibration is not enough

    NASA Astrophysics Data System (ADS)

    Kingsley, Jeffrey R.; Johnson, Leslie

    1999-12-01

    When added CD (Critical Dimension) capacity is needed there are several routes that can be taken -- add shifts and people to existing equipment, obtain additional equipment and staff or use an outside service provider for peak and emergency work. In all but the first scenario the qualification of the 'new' equipment, and correlation to the existing measurements, is key to meaningful results. In many cases simply calibrating the new tool with the same reference material or standard used to calibrate the existing tools will provide the level of agreement required. In fact, calibrating instruments using different standards can provide an acceptable level of agreement in cases where accuracy is a second tier consideration. However, there are also situations where factors outside of calibration can influence the results. In this study CD measurements from a mask sample being used to qualify an outside service provider showed good agreement for the narrower linewidths, but significant deviation occurred with increasing CD. In the course of a root cause investigation, it was found that there are a variety of factors that may influence the agreement found between two tools. What are these 'other factors' and how are they found? In the present case the results of a 'round robin' consensus from a variety of tools was used to initially determine which tool needed to be investigated. The instrument parameters felt to be the most important causes of the disagreement were identified and experiments run to test their influence. The factors investigated as the cause of the disagreement included (1) Type of detector and location with respect to sample, (2) Beam Voltage, (3) Scan Rotation/Sample Orientation issues and (4) Edge Detection Algorithm.

  3. Stability of Hydromorphone–Ketamine Solutions in Glass Bottles, Plastic Syringes, and IV Bags for Pediatric Use

    PubMed Central

    Ensom, Mary H H; Decarie, Diane; Leung, Karen; Montgomery, Carolyne

    2009-01-01

    Objectives: To evaluate the stability of mixtures of hydromorphone and ketamine in 0.9% sodium chloride (normal saline [NS]) after storage for up to 7 days at room temperature (25°C). Methods: The stability of 3 standard mixtures of hydromorphone and ketamine (hydromorphone 0.2 mg/mL + ketamine 0.2 mg/mL, hydromorphone 0.2 mg/mL + ketamine 0.6 mg/mL, and hydromorphone 0.2 mg/mL + ketamine 1.0 mg/mL) in NS was studied. Portions of each mixture were transferred to 3 brown glass bottles (100 mL), 3 plastic syringes (50 mL), and 3 IV bags (50 mL), which were then stored at room temperature (25°C). Physical characteristics, including pH, colour, and precipitation, were evaluated daily. Three 1.5-mL samples were collected from each bottle, syringe, and IV bag at baseline, at 24, 48, and 72 hours, and on day 7. Samples were analyzed in triplicate by a stability-indicating high-performance liquid chromatography method. Solutions were considered stable if they maintained 90% of the initial concentration of each drug. Samples from syringes and IV bags were subjected to standard sterility testing by incubation for 5 days in an enriched culture media. Results: No notable changes in pH or colour were observed, and no precipitation occurred in any of the solutions. All formulations maintained more than 90% of the initial concentration of each drug on day 7. No bacterial growth was observed in any of the samples tested. Conclusions: Mixtures of hydromorphone and ketamine were stable for up 7 days at 25°C, and the sterility of the preparations was maintained. Because stability alone does not guarantee efficacy, it is recommended that clinical studies be conducted to evaluate the pharmacokinetics and pharmacodynamics of these formulations. PMID:22478876

  4. Color-Coded Prefilled Medication Syringes Decrease Time to Delivery and Dosing Error in Simulated Emergency Department Pediatric Resuscitations

    PubMed Central

    Moreira, Maria E.; Hernandez, Caleb; Stevens, Allen D.; Jones, Seth; Sande, Margaret; Blumen, Jason R.; Hopkins, Emily; Bakes, Katherine; Haukoos, Jason S.

    2016-01-01

    Study objective The Institute of Medicine has called on the US health care system to identify and reduce medical errors. Unfortunately, medication dosing errors remain commonplace and may result in potentially life-threatening outcomes, particularly for pediatric patients when dosing requires weight-based calculations. Novel medication delivery systems that may reduce dosing errors resonate with national health care priorities. Our goal was to evaluate novel, prefilled medication syringes labeled with color-coded volumes corresponding to the weight-based dosing of the Broselow Tape, compared with conventional medication administration, in simulated pediatric emergency department (ED) resuscitation scenarios. Methods We performed a prospective, block-randomized, crossover study in which 10 emergency physician and nurse teams managed 2 simulated pediatric arrest scenarios in situ, using either prefilled, color-coded syringes (intervention) or conventional drug administration methods (control). The ED resuscitation room and the intravenous medication port were video recorded during the simulations. Data were extracted from video review by blinded, independent reviewers. Results Median time to delivery of all doses for the conventional and color-coded delivery groups was 47 seconds (95% confidence interval [CI] 40 to 53 seconds) and 19 seconds (95% CI 18 to 20 seconds), respectively (difference=27 seconds; 95% CI 21 to 33 seconds). With the conventional method, 118 doses were administered, with 20 critical dosing errors (17%); with the color-coded method, 123 doses were administered, with 0 critical dosing errors (difference=17%; 95% CI 4% to 30%). Conclusion A novel color-coded, prefilled syringe decreased time to medication administration and significantly reduced critical dosing errors by emergency physician and nurse teams during simulated pediatric ED resuscitations. PMID:25701295

  5. Comparison of drug delivery with autoinjector versus manual prefilled syringe and between three different autoinjector devices administered in pig thigh

    PubMed Central

    Hill, Robert L; Wilmot, John G; Belluscio, Beth A; Cleary, Kevin; Lindisch, David; Tucker, Robin; Wilson, Emmanuel; Shukla, Rajesh B

    2016-01-01

    Parenteral routes of drug administration are often selected to optimize actual dose of drug delivered, assure high bioavailability, bypass first-pass metabolism or harsh gastrointestinal environments, as well as maximize the speed of onset. Intramuscular (IM) delivery can be preferred to intravenous delivery when initiating intravenous access is difficult or impossible. Drugs can be injected intramuscularly using a syringe or an automated delivery device (autoinjector). Investigation into the IM delivery dynamics of these methods may guide further improvements in the performance of injection technologies. Two porcine model studies were conducted to compare differences in dispersion of injectate volume for different methods of IM drug administration. The first study compared the differences in the degree of dispersion and uptake of injectate following the use of a manual syringe and an autoinjector. The second study compared the spatial spread of the injected formulation, or dispersion volume, and uptake of injectate following the use of five different autoinjectors (EpiPen® [0.3 mL], EpiPen® Jr [0.3 mL], Twinject® [0.15 mL, 0.3 mL], and Anapen® 300 [0.3 mL]) with varying needle length, needle gauge, and force applied to the plunger. In the first study, the autoinjector provided higher peak volumes of injectate, indicating a greater degree of dispersion, compared with manual syringe delivery. In the second study, EpiPen autoinjectors resulted in larger dispersion volumes and higher initial dispersion ratios, which decreased rapidly over time, suggesting a greater rate of uptake of injectate than the other autoinjectors. The differences in dispersion and uptake of injectate are likely the result of different functional characteristics of the delivery systems. Both studies demonstrate that the functional characteristics of the method for delivering IM injections impact the dispersion and uptake of the material injected, which could significantly affect the

  6. Comparison of drug delivery with autoinjector versus manual prefilled syringe and between three different autoinjector devices administered in pig thigh.

    PubMed

    Hill, Robert L; Wilmot, John G; Belluscio, Beth A; Cleary, Kevin; Lindisch, David; Tucker, Robin; Wilson, Emmanuel; Shukla, Rajesh B

    2016-01-01

    Parenteral routes of drug administration are often selected to optimize actual dose of drug delivered, assure high bioavailability, bypass first-pass metabolism or harsh gastrointestinal environments, as well as maximize the speed of onset. Intramuscular (IM) delivery can be preferred to intravenous delivery when initiating intravenous access is difficult or impossible. Drugs can be injected intramuscularly using a syringe or an automated delivery device (autoinjector). Investigation into the IM delivery dynamics of these methods may guide further improvements in the performance of injection technologies. Two porcine model studies were conducted to compare differences in dispersion of injectate volume for different methods of IM drug administration. The first study compared the differences in the degree of dispersion and uptake of injectate following the use of a manual syringe and an autoinjector. The second study compared the spatial spread of the injected formulation, or dispersion volume, and uptake of injectate following the use of five different autoinjectors (EpiPen(®) [0.3 mL], EpiPen(®) Jr [0.3 mL], Twinject(®) [0.15 mL, 0.3 mL], and Anapen(®) 300 [0.3 mL]) with varying needle length, needle gauge, and force applied to the plunger. In the first study, the autoinjector provided higher peak volumes of injectate, indicating a greater degree of dispersion, compared with manual syringe delivery. In the second study, EpiPen autoinjectors resulted in larger dispersion volumes and higher initial dispersion ratios, which decreased rapidly over time, suggesting a greater rate of uptake of injectate than the other autoinjectors. The differences in dispersion and uptake of injectate are likely the result of different functional characteristics of the delivery systems. Both studies demonstrate that the functional characteristics of the method for delivering IM injections impact the dispersion and uptake of the material injected, which could significantly affect the

  7. Increasing Syringe Access and HIV Prevention in California: Findings from a Survey of Local Health Jurisdiction Key Personnel

    PubMed Central

    Garfein, Richard S.; Ross, Alessandra; Truax, Steven R.

    2006-01-01

    This article presents results from the first survey of California local health jurisdictions (LHJs) subsequent to passage of legislation that allows for over-the-counter pharmacy sales of syringes. In 2004 Governor Arnold Schwarzenegger signed Senate Bill 1159 (SB1159) into law to “prevent the spread of HIV, hepatitis and other blood-borne disease among drug users, their sexual partners and their children.” This legislation permits counties and cities to authorize a local disease prevention demonstration project (DPDP). Once authorized, a DPDP permits individuals to legally purchase and possess up to ten syringes from registered pharmacies without a doctor’s prescription. From June to August 2005, we surveyed health departments in all 61 LHJs to assess implementation status of SB1159. Fifty-seven (93%) LHJs responded. Nine (16%) had approved a DPDP by August 2005, 17 (30%) were in the process of obtaining authorization, and 18 (32%) anticipated that SB1159 would never be authorized in their LHJ. Among LHJs that do not plan to approve a DPDP (n = 18), the reasons included: strong community opposition (41%), competing priorities (35%), law enforcement opposition (29%), and little or no interest among pharmacies (29%). In LHJs that have authorized a DPDP, 31.4% of pharmacies registered to legally sell nonprescription syringes. Preliminary results indicate that local coalitions, comprised of public health, waste management and pharmacy officials, have been instrumental in facilitating DPDP authorization. Further research is needed to identify facilitators and barriers to adopting SB1159, to identify areas for improving technical assistance to implementers, and to assess the public health impact of the legislation. PMID:17151941

  8. What do pharmacists think about New York state's new nonprescription syringe sale program? Results of a survey.

    PubMed

    Klein, S J; Harris-Valente, K; Candelas, A R; Radigan, M; Narcisse-Pean, M; Tesoriero, J M; Birkhead, G S

    2001-12-01

    Access to sterile syringes can prevent transmission of blood-borne diseases such as human immunodeficiency virus (HIV) and hepatitis B and C. We conducted survey of attitudes of pharmacists to aid in development of the Expanded Syringe Access Demonstration Program (ESAP) in New York State. ESAP is an HIV prevention initiative that authorizes nonprescription sale of hypodermic needles and syringes by registered pharmacies in New York State beginning January 1, 2001. As part of planning for program implementation, the New York State Department of Health (NYSDOH), in collaboration with the New York State Education Department, conducted mailed survey of all 4, 392 licensed pharmacies in New York State during the summer of 2000. Some surveys (171) were returned as undeliverable. Of the 4,221 eligible respondents, 874 (20.7%) completed surveys were received, of which 574 (65.7%) indicated that their pharmacy would likely participate in ESAP. An additional 11.0% were not sure. Only 139 (15.9%) indicated that they would definitely not participate; 7.4% left this question blank. There were 608 responses to questions on safe disposal practices. Of these, 315 (51.8%) respondents indicated that their pharmacy sold sharps containers, and an additional 29 made them available at no cost. Only 133 (21.9%) respondents to this question did not offer sharps containers and were not interested in doing so. In all, 54 responses indicated that they accepted used hypodermic needles and syringes for disposal. Some (170, 28%) that did not accept sharps for disposal were interested in doing so. More than half (382, 63.0%) did not wish to do so. NYSDOH considered respondent suggestions and minimized ESAP requirements. By March 31, 2001, only 3 months after ESAP became effective, more than half of all licensed pharmacies in New York State were registered for ESAP. Survey results provided useful information to NYSDOH and good indication of likelihood of registration. The high level of pharmacy

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

    PubMed

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

    2015-01-01

    Unsafe injection practices significantly increase the risk of hepatitis C virus (HCV) 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 or 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 the IDUs reported unsafe injection practices. 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

  10. 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

  11. Radiometer Calibration and Characterization

    Energy Science and Technology Software Center (ESTSC)

    1994-12-31

    The Radiometer Calibration and Characterization (RCC) software is a data acquisition and data archival system for performing Broadband Outdoor Radiometer Calibrations (BORCAL). RCC provides a unique method of calibrating solar radiometers using techniques that reduce measurement uncertainty and better characterize a radiometer’s response profile. The RCC software automatically monitors and controls many of the components that contribute to uncertainty in an instrument’s responsivity.

  12. LWIR polarimeter calibration

    NASA Astrophysics Data System (ADS)

    Blumer, Robert V.; Miller, Miranda A.; Howe, James D.; Stevens, Mark A.

    2002-01-01

    Performance reported efforts to calibrate a MWIR imaging polarimeter met with moderate success. Recent efforts to calibrate a LWIR sensor using a different technique have been much more fruitful. For our sensor, which is based on a rotating retarder, we have improved system calibration substantially be including nonuniformity correction at all measurement positions of the retarder in our polarization data analysis. This technique can account for effects such as spurious optical reflections within a camera system that had been masquerading as false polarization in our previous data analysis methodology. Our techniques will be described and our calibration results will be quantified. Data from field-testing will be presented.

  13. The Science of Calibration

    NASA Astrophysics Data System (ADS)

    Kent, S. M.

    2016-05-01

    This paper presents a broad overview of the many issues involved in calibrating astronomical data, covering the full electromagnetic spectrum from radio waves to gamma rays, and considering both ground-based and space-based missions. These issues include the science drivers for absolute and relative calibration, the physics behind calibration and the mechanisms used to transfer it from the laboratory to an astronomical source, the need for networks of calibrated astronomical standards, and some of the challenges faced by large surveys and missions.

  14. Energy calibration via correlation

    NASA Astrophysics Data System (ADS)

    Maier, Daniel; Limousin, Olivier

    2016-03-01

    The main task of an energy calibration is to find a relation between pulse-height values and the corresponding energies. Doing this for each pulse-height channel individually requires an elaborated input spectrum with an excellent counting statistics and a sophisticated data analysis. This work presents an easy to handle energy calibration process which can operate reliably on calibration measurements with low counting statistics. The method uses a parameter based model for the energy calibration and concludes on the optimal parameters of the model by finding the best correlation between the measured pulse-height spectrum and multiple synthetic pulse-height spectra which are constructed with different sets of calibration parameters. A CdTe-based semiconductor detector and the line emissions of an 241Am source were used to test the performance of the correlation method in terms of systematic calibration errors for different counting statistics. Up to energies of 60 keV systematic errors were measured to be less than ~ 0.1 keV. Energy calibration via correlation can be applied to any kind of calibration spectra and shows a robust behavior at low counting statistics. It enables a fast and accurate calibration that can be used to monitor the spectroscopic properties of a detector system in near realtime.

  15. 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.

  16. 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.

  17. Aggregation and Particle Formation of Therapeutic Proteins in Contact With a Novel Fluoropolymer Surface Versus Siliconized Surfaces: Effects of Agitation in Vials and in Prefilled Syringes.

    PubMed

    Teska, Brandon M; Brake, Jeffrey M; Tronto, Gregory S; Carpenter, John F

    2016-07-01

    We examined the effects of an accelerated agitation protocol on 2 protein therapeutics, intravenous immunoglobulin (IVIG) and Avastin (bevacizumab), in contact with a novel fluoropolymer surface and more typical siliconized surfaces. The fluoropolymer surface provides "solid-phase" lubrication for the syringe plunger-obviating the need for silicone oil lubrication in prefilled syringes. We tested the 2 surfaces in a vial system and in prefilled glass syringes. We also examined the effects of 2 buffers, phosphate-buffered saline (PBS) and 0.2-M glycine, with and without the addition of polysorbate 20, on agitation-induced aggregation of IVIG. Aggregation was monitored by measuring subvisible particle formation and soluble protein loss. In both vials and syringes, protein particle formation was much lower during agitation with the fluoropolymer surface than with the siliconized surface. Also, particle formation was greater in PBS than in glycine buffer, an effect attributed to lower colloidal stability of IVIG in PBS. Polysorbate 20 in the formulation greatly inhibited protein particle formation. Overall, the fluoropolymer plunger surface in an unsiliconized glass barrel was demonstrated to be a viable solution for eliminating silicone oil droplets from prefilled syringe formulations and providing a consistent system for rationale formulation development and simplified particle analysis. PMID:27233685

  18. 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

  19. 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

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

    PubMed Central

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

    2007-01-01

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

  1. 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

  2. Estrogens determination in wastewater samples by automatic in-syringe dispersive liquid-liquid microextraction prior silylation and gas chromatography.

    PubMed

    González, Alba; Avivar, Jessica; Cerdà, Víctor

    2015-09-25

    A new procedure for the extraction, preconcentration and simultaneous determination of the estrogens most used in contraception pharmaceuticals (estrone, 17β-estradiol, estriol, and 17α-ethynylestradiol), cataloged as Contaminants of Emergent Concern by the Environmental Protection Agency of the United States (US-EPA), is proposed. The developed system performs an in-syringe magnetic stirring-assisted dispersive liquid-liquid microextraction (in-syringe-MSA-DLLME) prior derivatization and gas chromatography (GC-MS). Different extraction (carbon tetrachloride, ethyl acetate, chloroform and trichloroethylene) and disperser solvents (acetone, acetonitrile and methanol) were tested. Chloroform and acetone were chosen as extraction and disperser solvent, respectively, as they provided the best extraction efficiency. Then, a multivariate optimization of the extraction conditions was carried out. Derivatization conditions were also studied to ensure the conversion of the estrogens to their respective trimethylsilyl derivatives. Low LODs and LOQs were achieved, i.e. between 11 and 82ngL(-1), and 37 and 272ngL(-1), respectively. Good values for intra and inter-day precision were obtained (RSDs≤7.06% and RSD≤7.11%, respectively). The method was successfully applied to wastewater samples. PMID:26319623

  3. Parabens determination in cosmetic and personal care products exploiting a multi-syringe chromatographic (MSC) system and chemiluminescent detection.

    PubMed

    Rodas, Melisa; Portugal, Lindomar A; Avivar, Jessica; Estela, José Manuel; Cerdà, Víctor

    2015-10-01

    Parabens are widely used in dairy products, such as in cosmetics and personal care products. Thus, in this work a multi-syringe chromatographic (MSC) system is proposed for the first time for the determination of four parabens: methylparaben (MP), ethylparaben (EP), propylparaben (PP) and butylparaben (BP) in cosmetics and personal care products, as a simpler, practical, and low cost alternative to HPLC methods. Separation was achieved using a 5mm-long precolumn of reversed phase C18 and multi-isocratic separation, i.e. using two consecutive mobile phases, 12:88 acetonitrile:water and 28:72 acetonitrile:water. The use of a multi-syringe buret allowed the easy implementation of chemiluminescent (CL) detection after separation. The chemiluminescent detection is based on the reduction of Ce(IV) by p-hydroxybenzoic acid, product of the acid hydrolysis of parabens, to excite rhodamine 6G (Rho 6G) and measure the resulting light emission. Multivariate designs combined with the concepts of multiple response treatments and desirability functions have been employed to simultaneously optimize and evaluate the responses. The optimized method has proved to be sensitive and precise, obtaining limits of detection between 20 and 40 µg L(-1) and RSD <4.9% in all cases. The method was satisfactorily applied to cosmetics and personal care products, obtaining no significant differences at a confidence level of 95% comparing with the HPLC reference method. PMID:26078157

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. Nonlinear Observers for Gyro Calibration

    NASA Technical Reports Server (NTRS)

    Thienel, Julie; Sanner, Robert M.

    2003-01-01

    High precision estimation and control algorithms, to achieve unprecedented levels of pointing accuracy, will be required to support future formation flying missions such as interferometry missions. Achieving high pointing accuracy requires precise knowledge of the spacecraft rotation rate. Typically, the rotation rate is measured by a gyro. The measured rates can be corrupted by errors in alignment and scale factor, gyro biases, and noise. In this work, we present nonlinear observers for gyro calibration. Nonlinear observers are superior to extended or pseudo-linear Kalman filter type approaches for large errors and global stability. Three nonlinear gyro calibration observers are developed. The first observer estimates a constant gyro bias. The second observer estimates scale factor errors. The third observer estimates the gyro alignment for three orthogonal gyros. The convergence properties of all three observers are discussed. Additionally, all three observers are coupled with a nonlinear control algorithm. The stability of each of the resulting closed loop systems is analyzed. The observers are then combined, and the gyro calibration parameters are estimated simultaneously. The stability of the combined observers is addressed, as well as the stability of the resulting closed loop systems. Simulated test results are presented for each scenario. Finally, the nonlinear observers are compared to a pseudo-linear Kalman filter.

  9. Evidence for a substantial role of sharing of injecting paraphernalia other than syringes/needles to the spread of hepatitis C among injecting drug users.

    PubMed

    Mathei, C; Shkedy, Z; Denis, B; Kabali, C; Aerts, M; Molenberghs, G; Van Damme, P; Buntinx, F

    2006-08-01

    In industrialized countries, transmission of hepatitis C occurs primarily through injecting drug use. Transmission of hepatitis C in injecting drug users is mainly associated with the sharing of contaminated syringes/needles, although evidence for risk of hepatitis C infection through sharing of other injecting paraphernalia is increasing. In this paper, the independent effects of sharing paraphernalia other than syringes/needles have been estimated. The prevalence and force of infection were modelled using three serological data sets from drug users in three centres in Belgium as a function of the sharing behaviour. It was found that sharing of materials other than syringes/needles indeed seemed to contribute substantially to the spread of hepatitis C among injecting drug users. PMID:16901287

  10. 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.

  11. 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

  12. 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

  13. Calibration method for spectroscopic systems

    DOEpatents

    Sandison, David R.

    1998-01-01

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

  14. 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.

  15. Mission history of reflective solar band calibration performance of VIIRS

    NASA Astrophysics Data System (ADS)

    Moy, G.; Rausch, K.; Haas, E.; Wilkinson, T.; Cardema, J.; De Luccia, F.

    2015-09-01

    Environmental Data Records (EDR) from the Visible Infrared Imaging Radiometer Suite (VIIRS) have a need for Reflective Solar Band (RSB) calibration errors of less than 0.1%. Throughout the mission history of VIIRS, the overall instrument calibrated response scale factor (F factor) has been calculated with a manual process that uses data at least one week old and up to two weeks old until a new calibration Look Up Table (LUT) is put into operation. This one to two week lag routinely adds more than 0.1% calibration error. In this paper, we discuss trending the solar diffuser degradation (H factor), a key component of the F factor, improving H factor accuracy with improved bidirectional reflectance distribution function (BRDF) and attenuation screen LUTs , trending F factor, and how using RSB Automated Calibration (RSBAutoCal) will eliminate the lag and look-ahead extrapolation error.

  16. Gemini facility calibration unit

    NASA Astrophysics Data System (ADS)

    Ramsay-Howat, Suzanne K.; Harris, John W.; Gostick, David C.; Laidlaw, Ken; Kidd, Norrie; Strachan, Mel; Wilson, Ken

    2000-08-01

    High-quality, efficient calibration instruments is a pre- requisite for the modern observatory. Each of the Gemini telescopes will be equipped with identical facility calibration units (GCALs) designed to provide wavelength and flat-field calibrations for the suite of instruments. The broad range of instrumentation planned for the telescopes heavily constrains the design of GCAL. Short calibration exposures are required over wavelengths from 0.3micrometers to 5micrometers , field sizes up to 7 arcminutes and spectral resolution from R-5 to 50,000. The output from GCAL must mimic the f-16 beam of the telescope and provide a uniform illumination of the focal plane. The calibration units are mounted on the Gemini Instrument Support Structure, two meters from the focal pane, necessitating the use of large optical components. We will discuss the opto-mechanical design of the Gemini calibration unit, with reference to those feature which allow these stringent requirements to be met. A novel reflector/diffuser unit replaces the integration sphere more normally found in calibration systems. The efficiency of this system is an order of magnitude greater than for an integration sphere. A system of two off-axis mirrors reproduces the telescope pupil and provides the 7 foot focal plane. The results of laboratory test of the uniformity and throughput of the GCAL will be presented.

  17. The COS Calibration Pipeline

    NASA Astrophysics Data System (ADS)

    Hodge, Philip E.; Kaiser, M. E.; Keyes, C. D.; Ake, T. B.; Aloisi, A.; Friedman, S. D.; Oliveira, C. M.; Shaw, B.; Sahnow, D. J.; Penton, S. V.; Froning, C. S.; Beland, S.; Osterman, S.; Green, J.; COS/STIS STScI Team; IDT, COS

    2008-05-01

    The Cosmic Origins Spectrograph, COS, (Green, J, et al., 2000, Proc SPIE, 4013) will be installed in the Hubble Space Telescope (HST) during the next servicing mission. This will be the most sensitive ultraviolet spectrograph ever flown aboard HST. The program (CALCOS) for pipeline calibration of HST/COS data has been developed by the Space Telescope Science Institute. As with other HST pipelines, CALCOS uses an association table to list the data files to be included, and it employs header keywords to specify the calibration steps to be performed and the reference files to be used. COS includes both a cross delay line detector for the far ultraviolet (FUV) and a MAMA detector for the near ultraviolet (NUV). CALCOS uses a common structure for both channels, but the specific calibration steps differ. The calibration steps include pulse-height filtering and geometric correction for FUV, and flat-field, deadtime, and Doppler correction for both detectors. A 1-D spectrum will be extracted and flux calibrated. Data will normally be taken in TIME-TAG mode, recording the time and location of each detected photon, although ACCUM mode will also be supported. The wavelength calibration uses an on-board spectral line lamp. To enable precise wavelength calibration, default operations will simultaneously record the science target and lamp spectrum by executing brief (tag-flash) lamp exposures at least once per external target exposure.

  18. 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.

  19. 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.

  20. Lidar Calibration Centre

    NASA Astrophysics Data System (ADS)

    Pappalardo, Gelsomina; Freudenthaler, Volker; Nicolae, Doina; Mona, Lucia; Belegante, Livio; D'Amico, Giuseppe

    2016-06-01

    This paper presents the newly established Lidar Calibration Centre, a distributed infrastructure in Europe, whose goal is to offer services for complete characterization and calibration of lidars and ceilometers. Mobile reference lidars, laboratories for testing and characterization of optics and electronics, facilities for inspection and debugging of instruments, as well as for training in good practices are open to users from the scientific community, operational services and private sector. The Lidar Calibration Centre offers support for trans-national access through the EC HORIZON2020 project ACTRIS-2.

  1. 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.

  2. Towards A Modern Calibration Of The 238U/235U Paleoredox Proxy: Apparent Uranium Isotope Fractionation Factor During U(VI)-U(IV) Reduction In The Black Sea

    NASA Astrophysics Data System (ADS)

    Rolison, J. M.; Stirling, C. H.; Middag, R.; Rijkenberg, M. J. A.; De Baar, H. J. W.

    2015-12-01

    The isotopic compositions of redox-sensitive metals, including uranium (U), in marine sediments have recently emerged as powerful diagnostic tracers of the redox state of the ancient ocean-atmosphere system. Interpretation of sedimentary isotopic information requires a thorough understating of the environmental controls on isotopic fractionation in modern anoxic environments before being applied to the paleo-record. In this study, the relationship between ocean anoxia and the isotopic fractionation of U was investigated in the water column and sediments of the Black Sea. The Black Sea is the world's largest anoxic basin and significant removal of U from the water column and high U accumulation rates in modern underlying sediments have been documented. Removal of U from the water column occurs during the redox transition of soluble U(VI) to relatively insoluble U(IV). The primary results of this study are two-fold. First, significant 238U/235U fractionation was observed in the water column of the Black Sea, suggesting the reduction of U induces 238U/235U fractionation with the preferential removal of 238U from the aqueous phase. Second, the 238U/235U of underlying sediments is related to the water column through the isotope fractionation factor of the reduction reaction but is influenced by mass transport processes. These results provide important constraints on the use of 238U/235U as a proxy of the redox state of ancient oceans.

  3. 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.

  4. WFPC2 Pipeline Calibration

    NASA Astrophysics Data System (ADS)

    Burrows, Chris

    2004-03-01

    This document contains a listing of all WFPC2 reference files, grouped by type, that are presently available in the Calibration Data Base (CDB) System, and a summary of how they are used in the calibration of WFPC2 data. A summary memo is kept on STEIS and kept up to date as the reference files change. That memo is intended to inform observers as to the quality of the calibration applied to their data by the PODPS pipeline processing and to provide an aid in selecting appropriate reference files for the re-calibration of WFPC2 observations. The datafiles may be requested by name from the STScI in the same fashion as any other nonproprietary data products.

  5. SRAM Detector Calibration

    NASA Technical Reports Server (NTRS)

    Soli, G. A.; Blaes, B. R.; Beuhler, M. G.

    1994-01-01

    Custom proton sensitive SRAM chips are being flown on the BMDO Clementine missions and Space Technology Research Vehicle experiments. This paper describes the calibration procedure for the SRAM proton detectors and their response to the space environment.

  6. Roundness calibration standard

    DOEpatents

    Burrus, Brice M.

    1984-01-01

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

  7. 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.

  8. 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.

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

    PubMed

    Pons, Carmen; Forteza, Rafael; Cerdà, Víctor

    2005-03-31

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

  10. 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.

  11. 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.

  12. Aerosol backscatter lidar calibration and data interpretation

    NASA Technical Reports Server (NTRS)

    Kavaya, M. J.; Menzies, R. T.

    1984-01-01

    A treatment of the various factors involved in lidar data acquisition and analysis is presented. This treatment highlights sources of fundamental, systematic, modeling, and calibration errors that may affect the accurate interpretation and calibration of lidar aerosol backscatter data. The discussion primarily pertains to ground based, pulsed CO2 lidars that probe the troposphere and are calibrated using large, hard calibration targets. However, a large part of the analysis is relevant to other types of lidar systems such as lidars operating at other wavelengths; continuous wave (CW) lidars; lidars operating in other regions of the atmosphere; lidars measuring nonaerosol elastic or inelastic backscatter; airborne or Earth-orbiting lidar platforms; and lidars employing combinations of the above characteristics.

  13. HAWC Timing Calibration

    NASA Astrophysics Data System (ADS)

    Kelley-Hoskins, Nathan; Huentemeyer, Petra; Matthews, John; Dingus, Brenda; HAWC Collaboration

    2011-04-01

    The High-Altitude Water Cherenkov (HAWC) Experiment is a second-generation high sensitivity gamma-ray and cosmic-ray detector that builds on the experience and technology of the Milagro observatory. HAWC utilizes the water Cherenkov technique to measure extensive air showers. Instead of a pond filled with water (as in Milagro), an array of closely packed water tanks with 3 PMTs each is used. The cosmic ray's direction will be reconstructed using the times when the PMTs in each tank are triggered. Therefore, the timing calibration will be crucial for reaching an angular resolution as low as 0.1 degrees. We propose to use a laser calibration system, patterned after the calibration system in Milagro. The HAWC optical calibration system uses less than 1 ns laser light pulses, directed into two optical fiber networks. Each network will use optical fan-outs and switches to direct light to specific tanks. The first network is used to measure the light transit time out to each pair of tanks, and the second network sends light to each tank, calibrating each tank's 3 PMTs. Time slewing corrections will be made using neutral density filters to control the light intensity over 4 orders of magnitude. This system is envisioned to run both continuously at a low rate, or at a high rate with many intensity levels. In this presentation, we present the design of the calibration system and first measurements of its performance.

  14. COBE ground segment gyro calibration

    NASA Technical Reports Server (NTRS)

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

    1991-01-01

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

  15. Acceptability of Rapid Point-of-Care Hepatitis C Tests Among People Who Inject Drugs and Utilize Syringe-Exchange Programs

    PubMed Central

    Barocas, Joshua A.; Linas, Benjamin P.; Kim, Arthur Y.; Fangman, John; Westergaard, Ryan P.

    2016-01-01

    People who inject drugs may benefit from point-of-care hepatitis C virus (HCV) testing offered at syringe exchanges. We sought to understand whether this population would be willing to undergo rapid HCV testing. We found that there was broad support for rapid HCV testing, especially among younger people who inject drugs with high perceived risk. PMID:27191007

  16. Multilevel Community-Based Intervention to Increase Access to Sterile Syringes Among Injection Drug Users Through Pharmacy Sales in New York City

    PubMed Central

    Fuller, Crystal M.; Galea, Sandro; Caceres, Wendy; Blaney, Shannon; Sisco, Sarah; Vlahov, David

    2007-01-01

    Objectives. Research has indicated that there is minimal use of pharmacies among injection drug users (IDUs) in specific neighborhoods and among Black and Hispanic IDUs. We developed a community-based participatory research partnership to determine whether a multilevel intervention would increase sterile syringe access through a new policy allowing nonprescription syringe sales in pharmacies. Methods. We targeted Harlem, NY (using the South Bronx for comparison), and disseminated informational material at community forums, pharmacist training programs, and counseling or outreach programs for IDUs. We compared cross-sectional samples in 3 target populations (pre- and postintervention): community members (attitudes and opinions), pharmacists (opinions and practices), and IDUs (risk behaviors). Results. Among community members (N = 1496) and pharmacists (N = 131), negative opinions of IDU syringe sales decreased in Harlem whereas there was either no change or an increase in negative opinions in the comparison community. Although pharmacy use by IDUs (N=728) increased in both communities, pharmacy use increased significantly among Black IDUs in Harlem, but not in the comparison community; syringe reuse significantly decreased in Harlem, but not in the comparison community. Conclusions. Targeting the individual and the social environment through a multilevel community-based intervention reduced high-risk behavior, particularly among Black IDUs. PMID:17138929

  17. Pharmacy staff characteristics associated with support for pharmacy-based HIV-testing in pharmacies participating in the New York State Expanded Access Syringe Exchange Program

    PubMed Central

    Amesty, Silvia; Blaney, Shannon; Crawford, Natalie D.; Rivera, Alexis V.; Fuller, Crystal

    2013-01-01

    Objective To determine support of in-pharmacy HIV-testing among pharmacy staff and the individual-level characteristics associated with in-pharmacy HIV testing support. Design Descriptive, nonexperimental, cross-sectional study. Setting New York City (NYC) during January 2008 to March 2009. Intervention 131 pharmacies registered in the Expanded Syringe Access Program (ESAP) completed a survey. Participants 480 pharmacy staff, including pharmacists, owners/managers, and technicians/clerks. Main outcome measures Support of in-pharmacy HIV testing. Results Support of in-pharmacy HIV testing is high among pharmacy staff (79.4%). Pharmacy staff that supported in-pharmacy vaccinations were significantly more likely to support in-pharmacy HIV testing. Pharmacy staff that think that selling syringes to IDUs causes the community to be littered with dirty syringes were significantly less likely to support in-pharmacy HIV testing. Conclusion Support for in-pharmacy HIV testing is high among our sample of ESAP pharmacy staff actively involved in non-prescription syringe sales. These findings suggest that active ESAP pharmacy staff may be amenable to providing HIV counseling and testing to injection drug users and warrants further investigation. PMID:22825227

  18. 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.

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

    DOEpatents

    Clifford, Harry J.

    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.

  20. Calibration of radionuclide calibrators in Canadian hospitals

    SciTech Connect

    Santry, D.C.

    1986-01-01

    The major user of radioactive isotopes in Canada is the medical profession. Because of this a program has been initiated at the National Research Council of Canada (NRCC) to assist the nuclear medicine community to determine more accurately, the rather large amounts of radioactive materials administered to patients either for therapeutic or medical diagnostics. Since radiation exposure to the human body has deleterious effects, it is important for the patient that the correct amount of radioactive material is administered to minimize the induction of a fatal cancer at a later time. Hospitals in many other countries have a legal requirement to have their instruments routinely calibrated and have previously entered into intercomparisons with other hospitals or their national standards laboratories. In Canada, hospitals and clinics can participate on a voluntary basis to have the proper operation of measuring devices (radionuclide calibrators in particular) examined through intercomparisons. The program looks primarily at laboratory performance. This includes not only the instrument's performance but the performance of the individual doing the procedure and the technical procedure or method employed. In an effort to provide personal assistance to those having problems, it is essential that the comparisons should be pertinent to the daily work of the laboratory and that the most capable technologist not be selected to carry out the assay.

  1. OPTIMUM FREQUENCY OF CALIBRATION MONITORING

    EPA Science Inventory

    The paper develops an algorithm by which to compute the optimal frequency of calibration monitoring to minimize the total cost of analyzing a set of samples and the required calibration standards. Optimum calibration monitoring is needed because of the high cost and calibration d...

  2. 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

  3. STIS Calibration Pipeline

    NASA Astrophysics Data System (ADS)

    Hulbert, S.; Hodge, P.; Lindler, D.; Shaw, R.; Goudfrooij, P.; Katsanis, R.; Keener, S.; McGrath, M.; Bohlin, R.; Baum, S.

    1997-05-01

    Routine calibration of STIS observations in the HST data pipeline is performed by the CALSTIS task. CALSTIS can: subtract the over-scan region and a bias image from CCD observations; remove cosmic ray features from CCD observations; correct global nonlinearities for MAMA observations; subtract a dark image; and, apply flat field corrections. In the case of spectral data, CALSTIS can also: assign a wavelength to each pixel; apply a heliocentric correction to the wavelengths; convert counts to absolute flux; process the automatically generated spectral calibration lamp observations to improve the wavelength solution; rectify two-dimensional (longslit) spectra; subtract interorder and sky background; and, extract one-dimensional spectra. CALSTIS differs in significant ways from the current HST calibration tasks. The new code is written in ANSI C and makes use of a new C interface to IRAF. The input data, reference data, and output calibrated data are all in FITS format, using IMAGE or BINTABLE extensions. Error estimates are computed and include contributions from the reference images. The entire calibration can be performed by one task, but many steps can also be performed individually.

  4. 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.

  5. GTC Photometric Calibration

    NASA Astrophysics Data System (ADS)

    di Cesare, M. A.; Hammersley, P. L.; Rodriguez Espinosa, J. M.

    2006-06-01

    We are currently developing the calibration programme for GTC using techniques similar to the ones use for the space telescope calibration (Hammersley et al. 1998, A&AS, 128, 207; Cohen et al. 1999, AJ, 117, 1864). We are planning to produce a catalogue with calibration stars which are suitable for a 10-m telescope. These sources will be not variable, non binary and do not have infrared excesses if they are to be used in the infrared. The GTC science instruments require photometric calibration between 0.35 and 2.5 microns. The instruments are: OSIRIS (Optical System for Imaging low Resolution Integrated Spectroscopy), ELMER and EMIR (Espectrógrafo Multiobjeto Infrarrojo) and the Acquisition and Guiding boxes (Di Césare, Hammersley, & Rodriguez Espinosa 2005, RevMexAA Ser. Conf., 24, 231). The catalogue will consist of 30 star fields distributed in all of North Hemisphere. We will use fields containing sources over the range 12 to 22 magnitude, and spanning a wide range of spectral types (A to M) for the visible and near infrared. In the poster we will show the method used for selecting these fields and we will present the analysis of the data on the first calibration fields observed.

  6. A miniature remote deadweight calibrator

    NASA Astrophysics Data System (ADS)

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

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

  7. Targetless Camera Calibration

    NASA Astrophysics Data System (ADS)

    Barazzetti, L.; Mussio, L.; Remondino, F.; Scaioni, M.

    2011-09-01

    In photogrammetry a camera is considered calibrated if its interior orientation parameters are known. These encompass the principal distance, the principal point position and some Additional Parameters used to model possible systematic errors. The current state of the art for automated camera calibration relies on the use of coded targets to accurately determine the image correspondences. This paper presents a new methodology for the efficient and rigorous photogrammetric calibration of digital cameras which does not require any longer the use of targets. A set of images depicting a scene with a good texture are sufficient for the extraction of natural corresponding image points. These are automatically matched with feature-based approaches and robust estimation techniques. The successive photogrammetric bundle adjustment retrieves the unknown camera parameters and their theoretical accuracies. Examples, considerations and comparisons with real data and different case studies are illustrated to show the potentialities of the proposed methodology.

  8. Automatic beamline calibration procedures

    SciTech Connect

    Corbett, W.J.; Lee, M.J.; Zambre, Y.

    1992-03-01

    Recent experience with the SLC and SPEAR accelerators have led to a well-defined set of procedures for calibration of the beamline model using the orbit fitting program, RESOLVE. Difference orbit analysis is used to calibrate quadrupole strengths, BPM sensitivities, corrector strengths, focusing effects from insertion devices, and to determine the source of dispersion and coupling errors. Absolute orbit analysis is used to locate quadrupole misalignments, BPM offsets, or beam loss. For light source applications, the photon beam source coordinates can be found. The result is an accurate model of the accelerator which can be used for machine control. In this paper, automatable beamline calibration procedures are outlined and illustrated with recent examples. 5 refs.

  9. 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.

  10. (Mis)use of (133)Ba as a calibration surrogate for (131)I in clinical activity calibrators.

    PubMed

    Zimmerman, B E; Bergeron, D E

    2016-03-01

    Using NIST-calibrated solutions of (131)Ba and (131)I in the 5mL NIST ampoule geometry, measurements were made in three NIST-maintained Capintec activity calibrators and the NIST Vinten 671 ionization chamber to evaluate the suitability of using (133)Ba as a calibration surrogate for (131)I. For the Capintec calibrators, the (133)Ba response was a factor of about 300% higher than that of the same amount of (131)I. For the Vinten 671, the Ba-133 response was about 7% higher than that of (131)I. These results demonstrate that (133)Ba is a poor surrogate for (131)I. New calibration factors for these radionuclides in the ampoule geometry for the Vinten 671 and Capintec activity calibrators were also determined. PMID:26653213

  11. 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.

  12. Exploration of new multivariate spectral calibration algorithms.

    SciTech Connect

    Van Benthem, Mark Hilary; Haaland, David Michael; Melgaard, David Kennett; Martin, Laura Elizabeth; Wehlburg, Christine Marie; Pell, Randy J.; Guenard, Robert D.

    2004-03-01

    A variety of multivariate calibration algorithms for quantitative spectral analyses were investigated and compared, and new algorithms were developed in the course of this Laboratory Directed Research and Development project. We were able to demonstrate the ability of the hybrid classical least squares/partial least squares (CLSIPLS) calibration algorithms to maintain calibrations in the presence of spectrometer drift and to transfer calibrations between spectrometers from the same or different manufacturers. These methods were found to be as good or better in prediction ability as the commonly used partial least squares (PLS) method. We also present the theory for an entirely new class of algorithms labeled augmented classical least squares (ACLS) methods. New factor selection methods are developed and described for the ACLS algorithms. These factor selection methods are demonstrated using near-infrared spectra collected from a system of dilute aqueous solutions. The ACLS algorithm is also shown to provide improved ease of use and better prediction ability than PLS when transferring calibrations between near-infrared calibrations from the same manufacturer. Finally, simulations incorporating either ideal or realistic errors in the spectra were used to compare the prediction abilities of the new ACLS algorithm with that of PLS. We found that in the presence of realistic errors with non-uniform spectral error variance across spectral channels or with spectral errors correlated between frequency channels, ACLS methods generally out-performed the more commonly used PLS method. These results demonstrate the need for realistic error structure in simulations when the prediction abilities of various algorithms are compared. The combination of equal or superior prediction ability and the ease of use of the ACLS algorithms make the new ACLS methods the preferred algorithms to use for multivariate spectral calibrations.

  13. PERSONALISED BODY COUNTER CALIBRATION USING ANTHROPOMETRIC PARAMETERS.

    PubMed

    Pölz, S; Breustedt, B

    2016-09-01

    Current calibration methods for body counting offer personalisation for lung counting predominantly with respect to ratios of body mass and height. Chest wall thickness is used as an intermediate parameter. This work revises and extends these methods using a series of computational phantoms derived from medical imaging data in combination with radiation transport simulation and statistical analysis. As an example, the method is applied to the calibration of the In Vivo Measurement Laboratory (IVM) at Karlsruhe Institute of Technology (KIT) comprising four high-purity germanium detectors in two partial body measurement set-ups. The Monte Carlo N-Particle (MCNP) transport code and the Extended Cardiac-Torso (XCAT) phantom series have been used. Analysis of the computed sample data consisting of 18 anthropometric parameters and calibration factors generated from 26 photon sources for each of the 30 phantoms reveals the significance of those parameters required for producing an accurate estimate of the calibration function. Body circumferences related to the source location perform best in the example, while parameters related to body mass show comparable but lower performances, and those related to body height and other lengths exhibit low performances. In conclusion, it is possible to give more accurate estimates of calibration factors using this proposed approach including estimates of uncertainties related to interindividual anatomical variation of the target population. PMID:26396263

  14. Effect of contact stiffness on wedge calibration of lateral force in atomic force microscopy

    SciTech Connect

    Wang Fei; Zhao Xuezeng

    2007-04-15

    Quantitative friction measurement of nanomaterials in atomic force microscope requires accurate calibration method for lateral force. The effect of contact stiffness on lateral force calibration of atomic force microscope is discussed in detail and an improved calibration method is presented. The calibration factor derived from the original method increased with the applied normal load, which indicates that separate calibration should be required for every given applied normal load to keep the accuracy of friction measurement. We improve the original method by introducing the contact factor, which is derived from the contact stiffness between the tip and the sample, to the calculation of calibration factors. The improved method makes the calculation of calibration factors under different applied normal loads possible without repeating the calibration procedure. Comparative experiments on a silicon wafer have been done by both the two methods to validate the method in this article.

  15. SAR calibration: A technology review

    NASA Technical Reports Server (NTRS)

    Larson, R. W.; Politis, D. T.; Shuchman, R. A.

    1983-01-01

    Various potential applications of amplitude-calibrated SAR systems are briefly described, along with an estimate of calibration performance requirements. A review of the basic SAR calibration problem is given. For background purposes and to establish consistent definition of terms, various conventional SAR performance parameters are reviewed along with three additional parameters which are directly related to calibrated SAR systems. Techniques for calibrating a SAR are described. Included in the results presented are: calibration philosophy and procedures; review of the calibration signal generator technology development with results describing both the development of instrumentation and internal calibration measurements for two SAR systems; summary of analysis and measurements required to determine optimum retroreflector design and configuration for use as a reference for the absolute calibration of a SAR system; and summary of techniques for in-flight measurements of SAR antenna response.

  16. Primer on multivariate calibration

    SciTech Connect

    Thomas, E.V. )

    1994-08-01

    In analytical chemistry, calibration is the procedure that relates instrumental measurements to an analyte of interest. Typically, instrumental measurements are obtained from specimens in which the amount (or level) of the analyte has been determined by some independent and inherently accurate assay (e.g., wet chemistry). Together, the instrumental measurements and results from the independent assays are used to construct a model that relates the analyte level to the instrumental measurements. The advent of high-speed digital computers has greatly increased data acquisition and analysis capabilities and has provided the analytical chemist with opportunities to use many measurements - perhaps hundreds - for calibrating an instrument (e.g., absorbances at multiple wave-lengths). To take advantage of this technology, however, new methods (i.e., multivariate calibration methods) were needed for analyzing and modeling the experimental data. The purpose of this report is to introduce several evolving multivariate calibration methods and to present some important issues regarding their use. 30 refs., 7 figs.

  17. 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.

  18. NVLAP calibration laboratory program

    SciTech Connect

    Cigler, J.L.

    1993-12-31

    This paper presents an overview of the progress up to April 1993 in the development of the Calibration Laboratories Accreditation Program within the framework of the National Voluntary Laboratory Accreditation Program (NVLAP) at the National Institute of Standards and Technology (NIST).

  19. Calibration issues for MUSE

    NASA Astrophysics Data System (ADS)

    Kelz, Andreas; Roth, Martin; Bauer, Svend; Gerssen, Joris; Hahn, Thomas; Weilbacher, Peter; Laux, Uwe; Loupias, Magali; Kosmalski, Johan; McDermid, Richard; Bacon, Roland

    2008-07-01

    The Multi-Unit Spectroscopic Explorer (MUSE) is an integral-field spectrograph for the VLT for the next decade. Using an innovative field-splitting and slicing design, combined with an assembly of 24 spectrographs, MUSE will provide some 90,000 spectra in one exposure, which cover a simultaneous spectral range from 465 to 930nm. The design and manufacture of the Calibration Unit, the alignment tests of the Spectrograph and Detector sub-systems, and the development of the Data Reduction Software for MUSE are work-packages under the responsibility of the AIP, who is a partner in a European-wide consortium of 6 institutes and ESO, that is led by the Centre de Recherche Astronomique de Lyon. MUSE will be operated and therefore has to be calibrated in a variety of modes, which include seeing-limited and AO-assisted operations, providing a wide and narrow-field-of-view. MUSE aims to obtain unprecedented ultra-deep 3D-spectroscopic exposures, involving integration times of the order of 80 hours at the VLT. To achieve the corresponding science goals, instrumental stability, accurate calibration and adequate data reduction tools are needed. The paper describes the status at PDR of the AIP related work-packages, in particular with respect to the spatial, spectral, image quality, and geometrical calibration and related data reduction aspects.

  20. Improved Regression Calibration

    ERIC Educational Resources Information Center

    Skrondal, Anders; Kuha, Jouni

    2012-01-01

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

  1. 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.

  2. Commodity-Free Calibration

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Commodity-free calibration is a reaction rate calibration technique that does not require the addition of any commodities. This technique is a specific form of the reaction rate technique, where all of the necessary reactants, other than the sample being analyzed, are either inherent in the analyzing system or specifically added or provided to the system for a reason other than calibration. After introduction, the component of interest is exposed to other reactants or flow paths already present in the system. The instrument detector records one of the following to determine the rate of reaction: the increase in the response of the reaction product, a decrease in the signal of the analyte response, or a decrease in the signal from the inherent reactant. With this data, the initial concentration of the analyte is calculated. This type of system can analyze and calibrate simultaneously, reduce the risk of false positives and exposure to toxic vapors, and improve accuracy. Moreover, having an excess of the reactant already present in the system eliminates the need to add commodities, which further reduces cost, logistic problems, and potential contamination. Also, the calculations involved can be simplified by comparison to those of the reaction rate technique. We conducted tests with hypergols as an initial investigation into the feasiblility of the technique.

  3. 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.

  4. LOFAR Facet Calibration

    NASA Astrophysics Data System (ADS)

    van Weeren, R. J.; Williams, W. L.; Hardcastle, M. J.; Shimwell, T. W.; Rafferty, D. A.; Sabater, J.; Heald, G.; Sridhar, S. S.; Dijkema, T. J.; Brunetti, G.; Brüggen, M.; Andrade-Santos, F.; Ogrean, G. A.; Röttgering, H. J. A.; Dawson, W. A.; Forman, W. R.; de Gasperin, F.; Jones, C.; Miley, G. K.; Rudnick, L.; Sarazin, C. L.; Bonafede, A.; Best, P. N.; Bîrzan, L.; Cassano, R.; Chyży, K. T.; Croston, J. H.; Ensslin, T.; Ferrari, C.; Hoeft, M.; Horellou, C.; Jarvis, M. J.; Kraft, R. P.; Mevius, M.; Intema, H. T.; Murray, S. S.; Orrú, E.; Pizzo, R.; Simionescu, A.; Stroe, A.; van der Tol, S.; White, G. J.

    2016-03-01

    LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. LOFAR allows detailed sensitive high-resolution studies of the low-frequency radio sky. At the same time LOFAR also provides excellent short baseline coverage to map diffuse extended emission. However, producing high-quality deep images is challenging due to the presence of direction-dependent calibration errors, caused by imperfect knowledge of the station beam shapes and the ionosphere. Furthermore, the large data volume and presence of station clock errors present additional difficulties. In this paper we present a new calibration scheme, which we name facet calibration, to obtain deep high-resolution LOFAR High Band Antenna images using the Dutch part of the array. This scheme solves and corrects the direction-dependent errors in a number of facets that cover the observed field of view. Facet calibration provides close to thermal noise limited images for a typical 8 hr observing run at ∼ 5\\prime\\prime resolution, meeting the specifications of the LOFAR Tier-1 northern survey.

  5. Calibration Of Oxygen Monitors

    NASA Technical Reports Server (NTRS)

    Zalenski, M. A.; Rowe, E. L.; Mcphee, J. R.

    1988-01-01

    Readings corrected for temperature, pressure, and humidity of air. Program for handheld computer developed to ensure accuracy of oxygen monitors in National Transonic Facility, where liquid nitrogen stored. Calibration values, determined daily, based on entries of data on barometric pressure, temperature, and relative humidity. Output provided directly in millivolts.

  6. Simplified Vicarious Radiometric Calibration

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    A measurement-based radiance estimation approach for vicarious radiometric calibration of spaceborne multispectral remote sensing systems has been developed. This simplified process eliminates the use of radiative transfer codes and reduces the number of atmospheric assumptions required to perform sensor calibrations. Like prior approaches, the simplified method involves the collection of ground truth data coincident with the overpass of the remote sensing system being calibrated, but this approach differs from the prior techniques in both the nature of the data collected and the manner in which the data are processed. In traditional vicarious radiometric calibration, ground truth data are gathered using ground-viewing spectroradiometers and one or more sun photometer( s), among other instruments, located at a ground target area. The measured data from the ground-based instruments are used in radiative transfer models to estimate the top-of-atmosphere (TOA) target radiances at the time of satellite overpass. These TOA radiances are compared with the satellite sensor readings to radiometrically calibrate the sensor. Traditional vicarious radiometric calibration methods require that an atmospheric model be defined such that the ground-based observations of solar transmission and diffuse-to-global ratios are in close agreement with the radiative transfer code estimation of these parameters. This process is labor-intensive and complex, and can be prone to errors. The errors can be compounded because of approximations in the model and inaccurate assumptions about the radiative coupling between the atmosphere and the terrain. The errors can increase the uncertainty of the TOA radiance estimates used to perform the radiometric calibration. In comparison, the simplified approach does not use atmospheric radiative transfer models and involves fewer assumptions concerning the radiative transfer properties of the atmosphere. This new technique uses two neighboring uniform

  7. 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.

  8. 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 μm 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

  9. Error Modeling and Calibration for Encoded Sun Sensors

    PubMed Central

    Fan, Qiaoyun; Zhang, Guangjun; Li, Jian; Wei, Xinguo; Li, Xiaoyang

    2013-01-01

    Error factors in the encoded sun sensor (ESS) are analyzed and simulated. Based on the analysis results, an ESS error compensation model containing structural errors and fine-code algorithm errors is established, and the corresponding calibration method for model parameters is proposed. As external parameters, installation deviation between ESS and calibration equipment are introduced to the ESS calibration model, so that the model parameters can be calibrated accurately. The experimental results show that within plus/minus 60 degree of incident angle, the ESS measurement accuracy after compensation is three times higher on average than that before compensation. PMID:23470486

  10. Mercury Calibration System

    SciTech Connect

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

    2009-03-11

    U.S. Environmental Protection Agency (EPA) Performance Specification 12 in the Clean Air Mercury Rule (CAMR) states that a mercury CEM must be calibrated with National Institute for Standards and Technology (NIST)-traceable standards. In early 2009, a NIST traceable standard for elemental mercury CEM calibration still does not exist. Despite the vacature of CAMR by a Federal appeals court in early 2008, a NIST traceable standard is still needed for whatever regulation is implemented in the future. Thermo Fisher is a major vendor providing complete integrated mercury continuous emissions monitoring (CEM) systems to the industry. WRI is participating with EPA, EPRI, NIST, and Thermo Fisher towards the development of the criteria that will be used in the traceability protocols to be issued by EPA. An initial draft of an elemental mercury calibration traceability protocol was distributed for comment to the participating research groups and vendors on a limited basis in early May 2007. In August 2007, EPA issued an interim traceability protocol for elemental mercury calibrators. Various working drafts of the new interim traceability protocols were distributed in late 2008 and early 2009 to participants in the Mercury Standards Working Committee project. The protocols include sections on qualification and certification. The qualification section describes in general terms tests that must be conducted by the calibrator vendors to demonstrate that their calibration equipment meets the minimum requirements to be established by EPA for use in CAMR monitoring. Variables to be examined include linearity, ambient temperature, back pressure, ambient pressure, line voltage, and effects of shipping. None of the procedures were described in detail in the draft interim documents; however they describe what EPA would like to eventually develop. WRI is providing the data and results to EPA for use in developing revised experimental procedures and realistic acceptance criteria based on

  11. MODIS solar reflective calibration traceability

    NASA Astrophysics Data System (ADS)

    Xiong, Xiaoxiong; Butler, Jim

    2009-08-01

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

  12. MODIS Solar Reflective Calibration Traceability

    NASA Technical Reports Server (NTRS)

    Xiong, Xiaoxiong; Butler, Jim

    2009-01-01

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

  13. 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.

  14. Absolute calibration of sniffer probes on Wendelstein 7-X.

    PubMed

    Moseev, D; Laqua, H P; Marsen, S; Stange, T; Braune, H; Erckmann, V; Gellert, F; Oosterbeek, J W

    2016-08-01

    Here we report the first measurements of the power levels of stray radiation in the vacuum vessel of Wendelstein 7-X using absolutely calibrated sniffer probes. The absolute calibration is achieved by using calibrated sources of stray radiation and the implicit measurement of the quality factor of the Wendelstein 7-X empty vacuum vessel. Normalized absolute calibration coefficients agree with the cross-calibration coefficients that are obtained by the direct measurements, indicating that the measured absolute calibration coefficients and stray radiation levels in the vessel are valid. Close to the launcher, the stray radiation in the empty vessel reaches power levels up to 340 kW/m(2) per MW injected beam power. Furthest away from the launcher, i.e., half a toroidal turn, still 90 kW/m(2) per MW injected beam power is measured. PMID:27587121

  15. 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.

  16. Altazimuth mount based dynamic calibration method for GNSS attitude measurement

    NASA Astrophysics Data System (ADS)

    Jiang, Nan; He, Tao; Sun, Shaohua; Gu, Qing

    2015-02-01

    As the key process to ensure the test accuracy and quality, the dynamic calibration of the GNSS attitude measuring instrument is often embarrassed by the lack of the rigid enough test platform and an accurate enough calibration reference. To solve the problems, a novel dynamic calibration method for GNSS attitude measurement based on altazimuth mount is put forward in this paper. The principle and implementation of this method are presented, and then the feasibility and usability of the method are analyzed in detail involving the applicability of the mount, calibrating precision, calibrating range, base line rigidity and the satellite signal involved factors. Furthermore, to verify and test the method, a confirmatory experiment is carried out with the survey ship GPS attitude measuring instrument, and the experimental results prove that it is a feasible way to the dynamic calibration for GNSS attitude measurement.

  17. Absolute calibration of sniffer probes on Wendelstein 7-X

    NASA Astrophysics Data System (ADS)

    Moseev, D.; Laqua, H. P.; Marsen, S.; Stange, T.; Braune, H.; Erckmann, V.; Gellert, F.; Oosterbeek, J. W.

    2016-08-01

    Here we report the first measurements of the power levels of stray radiation in the vacuum vessel of Wendelstein 7-X using absolutely calibrated sniffer probes. The absolute calibration is achieved by using calibrated sources of stray radiation and the implicit measurement of the quality factor of the Wendelstein 7-X empty vacuum vessel. Normalized absolute calibration coefficients agree with the cross-calibration coefficients that are obtained by the direct measurements, indicating that the measured absolute calibration coefficients and stray radiation levels in the vessel are valid. Close to the launcher, the stray radiation in the empty vessel reaches power levels up to 340 kW/m2 per MW injected beam power. Furthest away from the launcher, i.e., half a toroidal turn, still 90 kW/m2 per MW injected beam power is measured.

  18. Stability of Diphenhydramine Hydrochloride, Lorazepam, and Dexamethasone Sodium Phosphate in 0.9% Sodium Chloride Stored in Polypropylene Syringes.

    PubMed

    Anderson, Collin R; Halford, Zachery; MacKay, Mark

    2015-01-01

    Chemotherapy induced nausea and vomiting is problematic for many patients undergoing chemotherapy. Multiple-drug treatments have been developed to mitigate chemotherapy induced nausea and vomiting. A patient-controlled infusion of diphenhydramine hydrochloride, lorazepam, and dexamethasone sodium phosphate has been studied in patients who are refractory to first-line therapy. Unfortunately, the physical and chemical compatibility of this three-drug combination is not available in the published literature. Chemical compatibility was evaluated using high-performance liquid chromatography with ultraviolet detection. Visual observation was employed to detect change in color, clarity, or gas evolution. Turbidity and pH measurements were performed in conjunction with visual observation at hours 0, 24, and 48. Results showed that diphenhydramine hydrochloride 4 mg/mL, lorazepam 0.16 mg/mL, and dexamethasone sodium phosphate 0.27 mg/mL in 0.9% sodium chloride stored in polypropylene syringes were compatible, and components retained greater than 95% of their original concentration over 48 hours when stored at room temperature. PMID:26625573

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

    PubMed

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

    2006-10-20

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

  20. Injection drug users as social actors: a stigmatized community's participation in the syringe exchange programmes of New York City.

    PubMed

    Henman, A R; Paone, D; Des Jarlais, D C; Kochems, L M; Friedman, S R

    1998-08-01

    In 1992, New York State Department of Health regulations provided for fully legal syringe exchange programmes in the state. The policies and procedures mandated that: 'Each program must seek to recruit ... for inclusion on its advisory board ... program participants ... Programs are also urged to establish other advisory bodies, such as Users' Advisory Boards made up of program participants, to provide input and guidance on program policies and operations.' The inclusion of drug users as official advisors to the legal programmes was seen as a method for incorporating the views of the consumers of the service in operational decisions. The 1992 regulations implied a new public image for users of illicit psychoactive drugs: active drug users were seen to be capable not only of self-protective actions (such as avoiding HIV infection), but also of serving as competent collaborators in programmes to preserve the public health. This development has important implications with regard to the evolution of official drug policy, since it will be difficult in future to treat IDUs simply as the passive objects of state intervention. Whether as individuals or representatives of a wider population of illicit drug users, they have acquired a legitimacy and sense of personal worth which would have been unthinkable in previous periods. PMID:9828960

  1. Determination of clenbuterol from pork samples using surface molecularly imprinted polymers as the selective sorbents for microextraction in packed syringe.

    PubMed

    Du, Wei; Lei, Chunmei; Zhang, Siruo; Bai, Gang; Zhou, Huiyan; Sun, Min; Fu, Qiang; Chang, Chun

    2014-03-01

    In this study, a selective sample pretreatment procedure combing surface molecularly imprinted polymers and microextraction in packed syringe (SMIPs-MEPS) was developed for the analysis of clenbuterol (CLB) from pork samples. SMIPs for CLB were synthesized on silica gel particles through a sol-gel process. A series of characterization and adsorption experiments revealed that the SMIPs exhibited porous structures, good thermal stability, high adsorption capacity and a fast mass transfer rate. The obtained SMIPs were employed as selective sorbents of SMIPs-MEPS for extraction of CLB from pork samples. Several parameters affecting the extraction efficiency were investigated, including the pH of sample solution, number of draw-eject cycles, volume of sample, type and volume of washing solution, and the type and volume of elution solution. Under the optimized conditions, a simple and rapid method for the determination of CLB from pork samples was established by coupling with high performance liquid chromatography (HPLC). The whole pretreatment process was rapid and it can be accomplished with 2min. The limit of quantitation and the limit of detection for CLB were 0.02 and 0.009μgkg(-1), respectively. The average recoveries of CLB at three spiked levels ranged from 86.5% to 91.2% with the relative standard deviations (RSD) ≤6.3%. PMID:24463040

  2. Fully-automated in-syringe dispersive liquid-liquid microextraction for the determination of caffeine in coffee beverages.

    PubMed

    Frizzarin, Rejane M; Maya, Fernando; Estela, José M; Cerdà, Víctor

    2016-12-01

    A novel fully-automated magnetic stirring-assisted lab-in-syringe analytical procedure has been developed for the fast and efficient dispersive liquid-liquid microextraction (DLLME) of caffeine in coffee beverages. The procedure is based on the microextraction of caffeine with a minute amount of dichloromethane, isolating caffeine from the sample matrix with no further sample pretreatment. Selection of the relevant extraction parameters such as the dispersive solvent, proportion of aqueous/organic phase, pH and flow rates have been carefully evaluated. Caffeine quantification was linear from 2 to 75mgL(-1), with detection and quantification limits of 0.46mgL(-1) and 1.54mgL(-1), respectively. A coefficient of variation (n=8; 5mgL(-1)) of a 2.1% and a sampling rate of 16h(-1), were obtained. The procedure was satisfactorily applied to the determination of caffeine in brewed, instant and decaf coffee samples, being the results for the sample analysis validated using high-performance liquid chromatography. PMID:27374593

  3. "Hooked on" prescription-type opiates prior to using heroin: results from a survey of syringe exchange clients.

    PubMed

    Peavy, K Michelle; Banta-Green, Caleb J; Kingston, Susan; Hanrahan, Michael; Merrill, Joseph O; Coffin, Phillip O

    2012-01-01

    The availability and diversion of prescription-type opioids increased dramatically in the first decade of the twenty-first century. One possible consequence of increased prescription opioid use and accessibility is the associated rise in opioid dependence, potentially resulting in heroin addiction. This study aimed to determine how common initial dependence on prescription-type opioids is among heroin injectors; associations with demographic and drug-using characteristics were also examined. Interview data were collected at syringe exchanges in King County, Washington in 2009. Among the respondents who had used heroin in the prior four months, 39% reported being "hooked on" prescription-type opioids first. Regression analysis indicated that younger age, sedative use and no recent crack use were independently associated with self-report of being hooked on prescription-type opioids prior to using heroin. These data quantify the phenomenon of being hooked on prescription-type opioids prior to initiating heroin use. Further research is needed to characterize the epidemiology, etiology and trajectory of prescription-type opioid and heroin use in the context of continuing widespread availability of prescription-type opioids. PMID:23061326

  4. Organizational Impact of the Introduction of a New Portable Syringe Pump for Iloprost Therapy in Italian Hospital Settings

    PubMed Central

    Restelli, Umberto; Faggioli, Paola; Scolari, Francesca; Gussoni, Gualberto; Valerio, Antonella; Sciascera, Alba; Croce, Davide; Mazzone, Antonino

    2015-01-01

    Purpose: The study aims at assessing the organizational and economic impact related to the use of a new portable syringe pump (Pompa Infonde®, Italfarmaco S.p.A., Cinisello Balsamo, Italy) at a hospital level. Methodology: Based on the HTA approach, the analysis assessed the organizational and economic impact of the new device at hospital level, using the traditional methods of Iloprost infusion as comparator. After a pilot evaluation, the organizational impact was assessed within 24 Italian hospitals. Structured interviews were conducted with clinicians and nurses. According to the Hospital-Based HTA approach, a questionnaire assessed the impact on human resources, training activities, internal meetings, spaces needed, facilities, clinical practice implications. Using Activity Based Costing approach, the economic evaluation was performed within the pilot center “Ospedale Civile” of Legnano, Italy. Findings: The new device leads to a positive managerial impact, with a substantial reduction of time to monitor patients by nurses. This resulted in a better management of human resources and in a reduction in nursing cost. Although a mild negative impact on training time for personnel, the structured interviews allowed the identification of three main areas of positive impact: (i) efficiency of internal processes, (ii) clinical pathways, (iii) synergies between wards. Originality: The organizational impact of Pompa Infonde®, showed that it is an efficient alternative to traditional methods, with benefits in the management of patients administered with Iloprost.

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

    PubMed Central

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

    2012-01-01

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

  6. Calibration of the Urbana lidar system

    NASA Technical Reports Server (NTRS)

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

    1980-01-01

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

  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. 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.

  9. 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.

  10. The Calibration Reference Data System

    NASA Astrophysics Data System (ADS)

    Greenfield, P.; Miller, T.

    2016-07-01

    We describe a software architecture and implementation for using rules to determine which calibration files are appropriate for calibrating a given observation. This new system, the Calibration Reference Data System (CRDS), replaces what had been previously used for the Hubble Space Telescope (HST) calibration pipelines, the Calibration Database System (CDBS). CRDS will be used for the James Webb Space Telescope (JWST) calibration pipelines, and is currently being used for HST calibration pipelines. CRDS can be easily generalized for use in similar applications that need a rules-based system for selecting the appropriate item for a given dataset; we give some examples of such generalizations that will likely be used for JWST. The core functionality of the Calibration Reference Data System is available under an Open Source license. CRDS is briefly contrasted with a sampling of other similar systems used at other observatories.

  11. Phase calibration generator

    NASA Technical Reports Server (NTRS)

    Sigman, E. H.

    1988-01-01

    A phase calibration system was developed for the Deep Space Stations to generate reference microwave comb tones which are mixed in with signals received by the antenna. These reference tones are used to remove drifts of the station's receiving system from the detected data. This phase calibration system includes a cable stabilizer which transfers a 20 MHz reference signal from the control room to the antenna cone. The cable stabilizer compensates for delay changes in the long cable which connects its control room subassembly to its antenna cone subassembly in such a way that the 20 MHz is transferred to the cone with no significant degradation of the hydrogen maser atomic clock stability. The 20 MHz reference is used by the comb generator and is also available for use as a reference for receiver LO's in the cone.

  12. Pipeline Calibration for STIS

    NASA Astrophysics Data System (ADS)

    Hodge, P. E.; Hulbert, S. J.; Lindler, D.; Busko, I.; Hsu, J.-C.; Baum, S.; McGrath, M.; Goudfrooij, P.; Shaw, R.; Katsanis, R.; Keener, S.; Bohlin, R.

    The CALSTIS program for calibration of Space Telescope Imaging Spectrograph data in the OPUS pipeline differs in several significant ways from calibration for earlier HST instruments, such as the use of FITS format, computation of error estimates, and association of related exposures. Several steps are now done in the pipeline that previously had to be done off-line by the user, such as cosmic ray rejection and extraction of 1-D spectra. Although the program is linked with IRAF for image and table I/O, it is written in ANSI C rather than SPP, which should make the code more accessible. FITS extension I/O makes use of the new IRAF FITS kernel for images and the HEASARC FITSIO package for tables.

  13. Multivariate Regression with Calibration*

    PubMed Central

    Liu, Han; Wang, Lie; Zhao, Tuo

    2014-01-01

    We propose a new method named calibrated multivariate regression (CMR) for fitting high dimensional multivariate regression models. Compared to existing methods, CMR calibrates the regularization for each regression task with respect to its noise level so that it is simultaneously tuning insensitive and achieves an improved finite-sample performance. Computationally, we develop an efficient smoothed proximal gradient algorithm which has a worst-case iteration complexity O(1/ε), where ε is a pre-specified numerical accuracy. Theoretically, we prove that CMR achieves the optimal rate of convergence in parameter estimation. We illustrate the usefulness of CMR by thorough numerical simulations and show that CMR consistently outperforms other high dimensional multivariate regression methods. We also apply CMR on a brain activity prediction problem and find that CMR is as competitive as the handcrafted model created by human experts. PMID:25620861

  14. 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.

  15. Calibrated vapor generator source

    DOEpatents

    Davies, John P.; Larson, Ronald A.; Goodrich, Lorenzo D.; Hall, Harold J.; Stoddard, Billy D.; Davis, Sean G.; Kaser, Timothy G.; Conrad, Frank J.

    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.

  16. 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

  17. Color-coded prefilled medication syringes decrease time to delivery and dosing errors in simulated prehospital pediatric resuscitations: A randomized crossover trial☆, ☆

    PubMed Central

    Stevens, Allen D.; Hernandez, Caleb; Jones, Seth; Moreira, Maria E.; Blumen, Jason R.; Hopkins, Emily; Sande, Margaret; Bakes, Katherine; Haukoos, Jason S.

    2016-01-01

    Background Medication dosing errors remain commonplace and may result in potentially life-threatening outcomes, particularly for pediatric patients where dosing often requires weight-based calculations. Novel medication delivery systems that may reduce dosing errors resonate with national healthcare priorities. Our goal was to evaluate novel, prefilled medication syringes labeled with color-coded volumes corresponding to the weight-based dosing of the Broselow Tape, compared to conventional medication administration, in simulated prehospital pediatric resuscitation scenarios. Methods We performed a prospective, block-randomized, cross-over study, where 10 full-time paramedics each managed two simulated pediatric arrests in situ using either prefilled, color-coded-syringes (intervention) or their own medication kits stocked with conventional ampoules (control). Each paramedic was paired with two emergency medical technicians to provide ventilations and compressions as directed. The ambulance patient compartment and the intravenous medication port were video recorded. Data were extracted from video review by blinded, independent reviewers. Results Median time to delivery of all doses for the intervention and control groups was 34 (95% CI: 28–39) seconds and 42 (95% CI: 36–51) seconds, respectively (difference = 9 [95% CI: 4–14] seconds). Using the conventional method, 62 doses were administered with 24 (39%) critical dosing errors; using the prefilled, color-coded syringe method, 59 doses were administered with 0 (0%) critical dosing errors (difference = 39%, 95% CI: 13–61%). Conclusions A novel color-coded, prefilled syringe decreased time to medication administration and significantly reduced critical dosing errors by paramedics during simulated prehospital pediatric resuscitations. PMID:26247145

  18. Subcutaneously administered methotrexate for rheumatoid arthritis, by prefilled syringes versus prefilled pens: patient preference and comparison of the self-injection experience

    PubMed Central

    Demary, Winfried; Schwenke, Holger; Rockwitz, Karin; Kästner, Peter; Liebhaber, Anke; Schoo, Ulrich; Hübner, Georg; Pichlmeier, Uwe; Guimbal-Schmolck, Cécile; Müller-Ladner, Ulf

    2014-01-01

    Purpose This multicenter, randomized, crossover study compared preference, ease of use, acceptability, satisfaction, and safety of repeated subcutaneous (SC) self-administrations with prefilled pens and prefilled syringes delivering methotrexate (MTX), in patients with rheumatoid arthritis (RA). Patients and methods The study (ClinicalTrials.gov number NCT01793259) enrolled 120 patients requiring initiation or intensification of MTX therapy for RA. Patients were randomized to receive the test drug, a prefilled pen (Metex® PEN/Metoject® PEN), or the reference drug, a prefilled syringe (Metex®/Metoject®), at doses of 15, 17.5, or 20 mg MTX SC once a week for 3 weeks. This was followed by receipt of the reference drug (prefilled syringe) or the test drug (prefilled pen) in a crossover design, with each patient serving as his/her own control. Questionnaires regarding patient preference, the Self-Injection Assessment Questionnaire (SIAQ), and diaries regarding local tolerability were used to document outcomes. Results Overall patient preference for the MTX prefilled pen was 75% (P<0.0001). In a six-item questionnaire, 73% to 76% of the patients preferred the prefilled pen in relation to use, acceptability, and satisfaction, and 67% of the patients confirmed that it did not take much effort to overcome SC self-injection with the pen. The SIAQ showed no clinical differences, in any domain scores, between both devices. Overall patient attitude towards self-injection at baseline was positive, as was patient experience with both devices during the study. As well, 92% of physicians and study nurses indicated that they would recommend the MTX prefilled pen to patients for future MTX treatment. The formulations were generally well tolerated. Conclusion SC self-injection of MTX with a prefilled pen was generally preferred, by patients with RA, over a prefilled syringe with regard to use, acceptability, and satisfaction. This is supported by the strong appreciation of their

  19. Faint Object Spectrograph (FOS) calibration

    NASA Technical Reports Server (NTRS)

    Harms, R. J.; Beaver, E. A.; Burbidge, E. M.; Angel, J. R. P.; Bartko, F.; Mccoy, J.; Ripp, L.; Bohlin, R.; Davidsen, A. F.; Ford, H.

    1982-01-01

    The Faint Object Spectrograph (FOS) designed for use with The Space Telescope (ST), is currently preparing for instrument assembly, integration, alignment, and calibration. Nearly all optical and detector elements have been completed and calibrated, and selection of flight detectors and all but a few optical elements has been made. Calibration results for the flight detectors and optics are presented, and plans for forthcoming system calibration are briefly described.

  20. 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.

  1. Fast calibration of gas flowmeters

    NASA Technical Reports Server (NTRS)

    Lisle, R. V.; Wilson, T. L.

    1981-01-01

    Digital unit automates calibration sequence using calculator IC and programmable read-only memory to solve calibration equations. Infrared sensors start and stop calibration sequence. Instrument calibrates mass flowmeters or rotameters where flow measurement is based on mass or volume. This automatic control reduces operator time by 80 percent. Solid-state components are very reliable, and digital character allows system accuracy to be determined primarily by accuracy of transducers.

  2. 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.

  3. Program Calibrates Strain Gauges

    NASA Technical Reports Server (NTRS)

    Okazaki, Gary D.

    1991-01-01

    Program dramatically reduces personnel and time requirements for acceptance tests of hardware. Data-acquisition system reads output from Wheatstone full-bridge strain-gauge circuit and calculates strain by use of shunt calibration technique. Program nearly instantaneously tabulates and plots strain data against load-cell outputs. Modified to acquire strain data for other specimens wherever full-bridge strain-gauge circuits used. Written in HP BASIC.

  4. Calibration Facilities for NIF

    SciTech Connect

    Perry, T.S.

    2000-06-15

    The calibration facilities will be dynamic and will change to meet the needs of experiments. Small sources, such as the Manson Source should be available to everyone at any time. Carrying out experiments at Omega is providing ample opportunity for practice in pre-shot preparation. Hopefully, the needs that are demonstrated in these experiments will assure the development of (or keep in service) facilities at each of the laboratories that will be essential for in-house preparation for experiments at NIF.

  5. Calibrated Properties Model

    SciTech Connect

    H. H. Liu

    2003-02-14

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

  6. [Quality control dose calibrators].

    PubMed

    Montoza Aguado, M; Delgado García, A; Ramírez Navarro, A; Salgado García, C; Muros de Fuentes, M A; Ortega Lozano, S; Bellón Guardia, M E; Llamas Elvira, J M

    2004-01-01

    We have reviewed the legislation about the quality control of dose calibrator. The importance of verifying the correct work of these instruments, is fundamental in daily practice of radiopharmacy and nuclear medicine. The Spanish legislation establishes to include these controls as part of the quality control of radiopharmaceuticals, and the program of quality assurance in nuclear medicine. We have reviewed guides and protocols from international eminent organizations, summarizing the recommended tests and periodicity of them. PMID:15625064

  7. Mesoscale hybrid calibration artifact

    DOEpatents

    Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.

    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.

  8. Optical Calibration of SNO+

    NASA Astrophysics Data System (ADS)

    Maneira, J.; Peeters, S.; Sinclair, J.

    2015-04-01

    SNO is being upgraded to SNO+, which has as its main goal the search for neutrinoless double-beta decay. The upgrade is defined by filling with a novel scintillator mixture containing 130Te. With a lower energy threshold than SNO, SNO+ will be sensitive to other exciting new physics. Here we are describing new optical calibration system that meets new, more stringent radiopurity requirements has been developed.

  9. Calibration Matters: Advances in Strapdown Airborne Gravimetry

    NASA Astrophysics Data System (ADS)

    Becker, D.

    2015-12-01

    Using a commercial navigation-grade strapdown inertial measurement unit (IMU) for airborne gravimetry can be advantageous in terms of cost, handling, and space consumption compared to the classical stable-platform spring gravimeters. Up to now, however, large sensor errors made it impossible to reach the mGal-level using such type IMUs as they are not designed or optimized for this kind of application. Apart from a proper error-modeling in the filtering process, specific calibration methods that are tailored to the application of aerogravity may help to bridge this gap and to improve their performance. Based on simulations, a quantitative analysis is presented on how much IMU sensor errors, as biases, scale factors, cross couplings, and thermal drifts distort the determination of gravity and the deflection of the vertical (DOV). Several lab and in-field calibration methods are briefly discussed, and calibration results are shown for an iMAR RQH unit. In particular, a thermal lab calibration of its QA2000 accelerometers greatly improved the long-term drift behavior. Latest results from four recent airborne gravimetry campaigns confirm the effectiveness of the calibrations applied, with cross-over accuracies reaching 1.0 mGal (0.6 mGal after cross-over adjustment) and DOV accuracies reaching 1.1 arc seconds after cross-over adjustment.

  10. Laboratory radiometric calibration for the convex grating imaging spectrometer

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

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

  11. 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.

  12. TIME CALIBRATED OSCILLOSCOPE SWEEP

    DOEpatents

    Owren, H.M.; Johnson, B.M.; Smith, V.L.

    1958-04-22

    The time calibrator of an electric signal displayed on an oscilloscope is described. In contrast to the conventional technique of using time-calibrated divisions on the face of the oscilloscope, this invention provides means for directly superimposing equal time spaced markers upon a signal displayed upon an oscilloscope. More explicitly, the present invention includes generally a generator for developing a linear saw-tooth voltage and a circuit for combining a high-frequency sinusoidal voltage of a suitable amplitude and frequency with the saw-tooth voltage to produce a resultant sweep deflection voltage having a wave shape which is substantially linear with respect to time between equal time spaced incremental plateau regions occurring once each cycle of the sinusoidal voltage. The foregoing sweep voltage when applied to the horizontal deflection plates in combination with a signal to be observed applied to the vertical deflection plates of a cathode ray oscilloscope produces an image on the viewing screen which is essentially a display of the signal to be observed with respect to time. Intensified spots, or certain other conspicuous indications corresponding to the equal time spaced plateau regions of said sweep voltage, appear superimposed upon said displayed signal, which indications are therefore suitable for direct time calibration purposes.

  13. 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.

  14. Vanillic and syringic acids from biomass burning: Behaviour during Fenton-like oxidation in atmospheric aqueous phase and in the absence of light.

    PubMed

    Santos, Gabriela T A D; Santos, Patrícia S M; Duarte, Armando C

    2016-08-01

    Biomass combustion is a threat to the environment since it emits to the atmosphere organic compounds, which may react and originate others more aggressive. This work studied the behaviours of vanillic and syringic acids, small aromatic tracers of biomass burning, during Fenton-like oxidation in aqueous phase and absence of light. For both compounds, the extent of oxidation increased with pH decrease from neutral to acid in atmospheric waters, but for vanillic acid the neutral pH was not able of promoting the oxidation. With the oxidation of both acids were formed chromophoric compounds, and the formation rate increased with the degree of electron-donator substituents in benzene ring. The initial and produced compounds were not totally degraded up to 24h of reaction at pH 4.5, suggesting that the night period may be not sufficient for their full degradation in atmospheric waters. The major compounds formed were the 3,4-dihydroxybenzoic acid for vanillic acid, and the 1,4-dihydroxy-2,6-dimethoxybenzene for syringic acid. These findings suggest the occurrence of an ipso attack by the hydroxyl radical preferential to the methoxy and carboxyl groups of vanillic and syringic acids, respectively. It is important to highlight that for both aromatic acids the main compounds produced are also small aromatic compounds. PMID:27085101

  15. Dynamic Calibration of Pressure Transducers

    NASA Technical Reports Server (NTRS)

    Hess, R. W.; Davis, W. T.; Davis, P. A.

    1985-01-01

    Sinusoidal calibration signal produced in 4- to 100-Hz range. Portable oscillating-pressure device measures dynamic characteristics of pressure transducers installed in models or aircraft at frequency and oscillating-pressure ranges encountered during unsteady-pressure-measurement tests. Calibration is over range of frequencies and amplitudes not available with commercial acoustic calibration devices.

  16. Internet-based calibration of a multifunction calibrator

    SciTech Connect

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

    2000-04-17

    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.

  17. 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.

  18. Calibration of triaxial fluxgate gradiometer

    SciTech Connect

    Vcelak, Jan

    2006-04-15

    The description of simple and fast calibration procedures used for double-probe triaxial fluxgate gradiometer is provided in this paper. The calibration procedure consists of three basic steps. In the first step both probes are calibrated independently in order to reach constant total field reading in every position. Both probes are numerically aligned in the second step in order that the gradient reading is zero in homogenous magnetic field. The third step consists of periodic drift calibration during measurement. The results and detailed description of each calibration step are presented and discussed in the paper. The gradiometer is finally verified during the detection of the metal object in the measuring grid.

  19. Calibration effects on orbit determination

    NASA Technical Reports Server (NTRS)

    Madrid, G. A.; Winn, F. B.; Zielenbach, J. W.; Yip, K. B.

    1974-01-01

    The effects of charged particle and tropospheric calibrations on the orbit determination (OD) process are analyzed. The calibration process consisted of correcting the Doppler observables for the media effects. Calibrated and uncalibrated Doppler data sets were used to obtain OD results for past missions as well as Mariner Mars 1971. Comparisons of these Doppler reductions show the significance of the calibrations. For the MM'71 mission, the media calibrations proved themselves effective in diminishing the overall B-plane error and reducing the Doppler residual signatures.

  20. Primary calibration in acoustics metrology

    NASA Astrophysics Data System (ADS)

    Bacelar Milhomem, T. A.; Defilippo Soares, Z. M.

    2015-01-01

    SI unit in acoustics is realized by the reciprocity calibrations of laboratory standard microphones in pressure field, free field and diffuse field. Calibrations in pressure field and in free field are already consolidated and the Inmetro already done them. Calibration in diffuse field is not yet consolidated, however, some national metrology institutes, including Inmetro, are conducting researches on this subject. This paper presents the reciprocity calibration, the results of Inmetro in recent key comparisons and the research that is being developed for the implementation of reciprocity calibration in diffuse field.

  1. 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.

  2. Comparison of magnetic probe calibration at nano and millitesla magnitudes

    NASA Astrophysics Data System (ADS)

    Pahl, Ryan A.; Rovey, Joshua L.; Pommerenke, David J.

    2014-01-01

    Magnetic field probes are invaluable diagnostics for pulsed inductive plasma devices where field magnitudes on the order of tenths of tesla or larger are common. Typical methods of providing a broadband calibration of dot{{B}} probes involve either a Helmholtz coil driven by a function generator or a network analyzer. Both calibration methods typically produce field magnitudes of tens of microtesla or less, at least three and as many as six orders of magnitude lower than their intended use. This calibration factor is then assumed constant regardless of magnetic field magnitude and the effects of experimental setup are ignored. This work quantifies the variation in calibration factor observed when calibrating magnetic field probes in low field magnitudes. Calibration of two dot{{B}} probe designs as functions of frequency and field magnitude are presented. The first dot{{B}} probe design is the most commonly used design and is constructed from two hand-wound inductors in a differential configuration. The second probe uses surface mounted inductors in a differential configuration with balanced shielding to further reduce common mode noise. Calibration factors are determined experimentally using an 80.4 mm radius Helmholtz coil in two separate configurations over a frequency range of 100-1000 kHz. A conventional low magnitude calibration using a vector network analyzer produced a field magnitude of 158 nT and yielded calibration factors of 15 663 ± 1.7% and 4920 ± 0.6% {T}/{V {s}} at 457 kHz for the surface mounted and hand-wound probes, respectively. A relevant magnitude calibration using a pulsed-power setup with field magnitudes of 8.7-354 mT yielded calibration factors of 14 615 ± 0.3% and 4507 ± 0.4% {T}/{V {s}} at 457 kHz for the surface mounted inductor and hand-wound probe, respectively. Low-magnitude calibration resulted in a larger calibration factor, with an average difference of 9.7% for the surface mounted probe and 12.0% for the hand-wound probe. The

  3. 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

  4. A variable acceleration calibration system

    NASA Astrophysics Data System (ADS)

    Johnson, Thomas H.

    2011-12-01

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

  5. 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.

  6. Automatic force balance calibration system

    NASA Technical Reports Server (NTRS)

    Ferris, Alice T. (Inventor)

    1996-01-01

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

  7. Automatic force balance calibration system

    NASA Astrophysics Data System (ADS)

    Ferris, Alice T.

    1995-05-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-10-01

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

  9. 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.

  10. 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.

  11. Calibration procedure for Slocum glider deployed optical instruments.

    PubMed

    Cetinić, 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

  12. 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.

  13. [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

  14. Statistical design of mass spectrometry calibration procedures

    SciTech Connect

    Bayne, C.K.

    1996-11-01

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

  15. A comparison of 1-year substance abuse treatment outcomes in community syringe exchange participants versus other referrals.

    PubMed

    Neufeld, Karin; King, Van; Peirce, Jessica; Kolodner, Ken; Brooner, Robert; Kidorf, Michael

    2008-09-01

    This longitudinal cohort study of 324 consecutive admissions to methadone maintenance treatment between 08/1994 and 09/1997 compared 1-year outcomes of opioid-dependent patients referred from a syringe exchange program (SEP; n=81) versus other sources (n=243). All participants received stepped-based counseling. The Addiction Severity Index was completed upon admission. Treatment outcomes were assessed using weekly urine testing and days in treatment. GEE regression models were used to evaluate the association between baseline variables and treatment outcomes. SEP referrals were older, included more males and African Americans, reported greater unemployment and heavier heroin, cocaine, and injection drug use at admission. During treatment, SEP referrals used more opioids (OR 2.57; 95% CI 1.86-3.56) and cocaine (OR 2.77; 95% CI 1.93-3.95), and were less likely to complete 1 year (35%) compared to other referrals (56%; hazard ratio 1.88; 95% CI 1.35-2.62). Nevertheless, referral source was not significantly associated with outcome when adjusted for baseline characteristics. Greater baseline frequency of substance and injection drug use, and younger age were positively associated with ongoing opioid and cocaine use. African American race and baseline unemployment were also associated with ongoing cocaine use. Younger age and greater baseline cocaine use were associated with poorer retention at 1 year. The poorer treatment response of SEP referrals is likely due to higher baseline problem severity. Specialized interventions may be required to reduce drug use and improve retention in this population. PMID:18486360

  16. High uptake of naloxone-based overdose prevention training among previously incarcerated syringe-exchange program participants

    PubMed Central

    Barocas, Joshua A.; Baker, Lisa; Hull, Shawnika J.; Stokes, Scott; Westergaard, Ryan P.

    2016-01-01

    Background Incarceration is common among people who inject drugs. Prior research has shown that incarceration is a marker of elevated risk for opioid overdose, suggesting that the criminal justice system may be an important, under-utilized venue for implementing overdose prevention strategies. To better understand the feasibility and acceptability of such strategies, we evaluated the utilization of naloxone-based overdose prevention training among people who inject drugs with and without a history of incarceration. Methods We surveyed clients who utilize a multi-site syringe exchange program (SEP) in 2 cities in the Midwestern United States. Participants completed an 88-item, computerized survey assessing history of incarceration, consequences associated with injection, injecting practices, and uptake of harm reduction strategies. Results Among 543 respondents who injected drugs in the prior 30 days, 243 (43%) reported prior incarceration. Comparing those with and without a history of incarceration, there were no significant differences with respect to age, gender, or race. Those who observed an overdose, experienced overdose, and received training to administer or have administered naloxone were more likely to report incarceration. Overall, 69% of previously incarcerated clients had been trained to administer naloxone. Conclusion People who inject drugs with a history of incarceration appear to have a higher risk of opioid overdose than those never incarcerated, and are more willing to utilize naloxone as an overdose prevention strategy. Naloxone training and distribution is an important component of comprehensive prevention services for persons with opioid use disorders. Expansion of services for persons leaving correctional facilities should be considered. PMID:26143300

  17. Antioxidant Activity of Syringic Acid Prevents Oxidative Stress in l-arginine–Induced Acute Pancreatitis: An Experimental Study on Rats

    PubMed Central

    Cikman, Oztekin; Soylemez, Omer; Ozkan, Omer Faruk; Kiraz, Hasan Ali; Sayar, Ilyas; Ademoglu, Serkan; Taysi, Seyithan; Karaayvaz, Muammer

    2015-01-01

    The aim of this study was to investigate the possible protective role of antioxidant treatment with syringic acid (SA) on l-arginine–induced acute pancreatitis (AP) using biochemical and histopathologic approaches. A total of 30 rats were divided into 3 groups. The control group received normal saline intraperitoneally. The AP group was induced by 3.2 g/kg body weight l-arginine intraperitoneally, administered twice with an interval of 1 hour between administrations. The AP plus SA group, after having AP induced by 3.2 g/kg body weight l-arginine, was given SA (50 mg kg−1) in 2 parts within 24 hours. The rats were killed, and pancreatic tissue was removed and used in biochemical and histopathologic examinations. Compared with the control group, the mean pancreatic tissue total oxidant status level, oxidative stress index, and lipid hydroperoxide levels were significantly increased in the AP group, being 30.97 ± 7.13 (P < 0.05), 1.76 ± 0.34 (P < 0.0001), and 19.18 ± 4.91 (P < 0.01), respectively. However, mean total antioxidant status and sulfhydryl group levels were significantly decreased in the AP group compared with the control group, being 1.765 ± 0.21 (P < 0.0001) and 0.21 ± 0.04 (P < 0.0001), respectively. SA reduces oxidative stress markers and has antioxidant effects. It also augments antioxidant capacity in l-arginine–induced acute toxicity of pancreas in rats. PMID:26011211

  18. SAR antenna calibration techniques

    NASA Technical Reports Server (NTRS)

    Carver, K. R.; Newell, A. C.

    1978-01-01

    Calibration of SAR antennas requires a measurement of gain, elevation and azimuth pattern shape, boresight error, cross-polarization levels, and phase vs. angle and frequency. For spaceborne SAR antennas of SEASAT size operating at C-band or higher, some of these measurements can become extremely difficult using conventional far-field antenna test ranges. Near-field scanning techniques offer an alternative approach and for C-band or X-band SARs, give much improved accuracy and precision as compared to that obtainable with a far-field approach.

  19. Structured light camera calibration

    NASA Astrophysics Data System (ADS)

    Garbat, P.; Skarbek, W.; Tomaszewski, M.

    2013-03-01

    Structured light camera which is being designed with the joined effort of Institute of Radioelectronics and Institute of Optoelectronics (both being large units of the Warsaw University of Technology within the Faculty of Electronics and Information Technology) combines various hardware and software contemporary technologies. In hardware it is integration of a high speed stripe projector and a stripe camera together with a standard high definition video camera. In software it is supported by sophisticated calibration techniques which enable development of advanced application such as real time 3D viewer of moving objects with the free viewpoint or 3D modeller for still objects.

  20. 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.

  1. 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.

  2. 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.

  3. Calibration of a visible polarimeter

    NASA Astrophysics Data System (ADS)

    Gibney, Mark

    2012-06-01

    The calibration of a visible polarimeter is discussed. Calibration coefficients that provide a complete linear characterization of a polarimeter are represented in this paper by the analyzer vector, where sensor response in counts is given by the dot product of the analyzer vector and the incoming Stokes vector. Using the analyzer vector to represent the effect of the sensor on the incoming Stokes vector, we can include elements of the calibration Stokes vector in the fit used to estimate the analyzer vectors/calibration coefficients. This technique allows us to alleviate some of the strict requirements usually levied on the source used to generate the calibration Stokes vectors, such as source temporal stability. Data will be shown that validate the resultant analyzer vectors/calibration coefficients, using a novel technique with a tilted glass plate. A discussion of how these techniques are applied to IR sensors will also be touched on.

  4. 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.

  5. Concept of ASTER calibration requirement

    NASA Technical Reports Server (NTRS)

    Ono, A.

    1992-01-01

    The document of ASTER Calibration Requirement specifies the following items related to spectral and radiometric characteristics of the ASTER instrument: (1) characteristics whose knowledge is specified, (2) requirement for knowledge of the characteristics, (3) methodology for characteristics evaluation, and (4) supplementary information and data related with characteristics evaluation. This document is applicable to the document of the ASTER Instrument Specification on Observational Performances, and will be a part of the ASTER Calibration Plan. ASTER Calibration Requirement is scheduled to establish the concept and framework by March 1992 when the 5th Calibration and Data Validation Panel Meeting is held, and to determine details including requirement values and evaluation methodologies by October 1992 around which the Calibration Peer Review may be held. The ASTER Calibration Plan is planned to finish by the same time.

  6. 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 μN or less depending on sphere size. Factors which significantly contribute to errors in the calibration were explored in detail and minimized.

  7. Application of In-Syringe Dispersive Liquid-Liquid Microextraction and Narrow-Bore Tube Dispersive Liquid-Liquid Microextraction for the Determination of Trace Amounts of BTEX in Water Samples.

    PubMed

    Rahmani, Mashaallah; Kaykhaii, Massoud; Ghasemi, Elham; Tahernejad, Mohadeseh

    2015-08-01

    Two new simple and effective methods based on dispersive liquid-liquid microextraction (DLLME) procedure, termed "in-syringe DLLME (IS-DLLME)" and "narrow-bore tube DLLME (NB-DLLME)", were developed and applied for rapid and simultaneous separation and preconcentration of trace amounts of benzene, toluene, ethylbenzene and xylene isomers in water samples followed by gas chromatographic analysis. Different parameters influencing the extraction efficiency of both methods such as type and volume of the extraction solvent and the disperser solvent; pH, temperature and volume of sample solution and ionic strength of samples were investigated and optimized. Under optimal condition, the limits of detection ranged from 1.7 to 2.4 µg L(-1) for IS-DLLME and 1.5 to 2.2 µg L(-1) for NB-DLLME. Precision (as relative standard deviation) of the two techniques was between 2.1 and 4.6% for IS-DLLME and between 1.5 and 4.5% for NB-DLLME. The enrichment factors found to be between 20-29 and 31-73 for IS- and NB-DLLME, respectively. The applicability of the proposed methods was investigated by analyzing real water samples. PMID:25595286

  8. 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, 20 µL 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 0.08-12 µg/L, for 3.5 mL sample volume. Linearity ranges were up to 500 µg/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

  9. Calorimeters for pulsed lasers: calibration.

    PubMed

    Thacher, P D

    1976-07-01

    A calibration technique is developed and tested in which a calorimeter used for single-shot laser pulse energy measurements is calibrated with reference to a cw power standard using a chopped cw laser beam. A pulsed laser is required only to obtain the relative time response of the calorimeter to a pulse. With precautions as to beam alignment and wavelength, the principal error of the technique is that of the cw standard. Calibration of two thermopiles with cone receivers showed -2.5% and -3.5% agreement with previous calibrations made by the National Bureau of Standards. PMID:20165270

  10. Neural networks for calibration tomography

    NASA Technical Reports Server (NTRS)

    Decker, Arthur

    1993-01-01

    Artificial neural networks are suitable for performing pattern-to-pattern calibrations. These calibrations are potentially useful for facilities operations in aeronautics, the control of optical alignment, and the like. Computed tomography is compared with neural net calibration tomography for estimating density from its x-ray transform. X-ray transforms are measured, for example, in diffuse-illumination, holographic interferometry of fluids. Computed tomography and neural net calibration tomography are shown to have comparable performance for a 10 degree viewing cone and 29 interferograms within that cone. The system of tomography discussed is proposed as a relevant test of neural networks and other parallel processors intended for using flow visualization data.

  11. RX130 Robot Calibration

    NASA Astrophysics Data System (ADS)

    Fugal, Mario

    2012-10-01

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

  12. LBA Calibrator Survey

    NASA Astrophysics Data System (ADS)

    Phillips, Chris; Petrov, Leonid; Bertarini, Alessandra

    2009-07-01

    The Australian LBA (Long Baseline Array) has been used to observe a list of candidate flat spectrum radio sources with declination < -50° to determine their position with milliarcsec accuracy and determine their suitability as calibrators for phase referencing observations and as target for astrometry and geodesy observations. Currently more than 316 new millisecond positions have been determined with a final goal of around 1000 astrometric positions for a high density phase reference grid. The candidate list is based on the AT20G survey, an all-sky 20 GHz survey using an 8 GHz analog correlator for the ATCA. So far a detection rate of candidate source of 97% has been achieved.

  13. 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.

  14. Atmospheric optical calibration system

    DOEpatents

    Hulstrom, Roland L.; Cannon, Theodore W.

    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.

  15. 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.

  16. Automatic flowmeter calibration system

    NASA Technical Reports Server (NTRS)

    Lisle, R. V.; Wilson, T. L. (Inventor)

    1981-01-01

    A system for automatically calibrating the accuracy of a flowmeter is described. The system includes a calculator capable of performing mathematical functions responsive to receiving data signals and function command signals. A prover cylinder is provided for measuring the temperature, pressure, and time required for accumulating a predetermined volume of fluid. Along with these signals, signals representing the temperature and pressure of the fluid going into the meter are fed to a plurality of data registers. Under control of a progress controller, the data registers are read out and the information is fed through a data select circuit to the calculator. Command signals are also produced by a function select circuit and are fed to the calculator set indicating the desired function to be performed. The reading is then compared with the reading produced by the flowmeter.

  17. 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.

  18. TOD to TTP calibration

    NASA Astrophysics Data System (ADS)

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

    2011-05-01

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

  19. A novel calibration method of CCD camera for LAMOST

    NASA Astrophysics Data System (ADS)

    Gu, Yonggang; Jin, Yi; Zhai, Chao

    2012-09-01

    Large Sky Area Multi-object Fiber Spectroscopic Telescope - LAMOST, with a 1.75m-diameter focal plane on which 4000 optical fibers are arranged, is one of major scientific projects in China. During the surveying process of LAMOST, the optical imaging system makes the astrometric objects be imaged in the focal plane, and the optical fiber positioning system controls the 4000 fibers to be aligned with these objects and obtain their spectrum. In order to correct the positioning error of these optical fibers, the CCD camera is used to detect these fibers’ position in the way of close-range photogrammetry. As we all know, the calibration quality of the CCD camera is one of the most important factors for detection precision. However, the camera calibration has two following problems in the field work of LAMOST. First, the camera parameters are not stable due to the changes of on-site work environment and the vibration during movement. So, the CCD camera must be on-line calibrated. Second, a large-size high-precision calibration target is needed to calibrate the camera, for the focal plane is very big. Making such a calibration target, it is very difficult and costly. Meanwhile, the large calibration target is hard to be fixed on LAMOST because of the space constraint. In this paper, an improved bundle adjustment self-calibration method is proposed to solve the two problems above. The results of experiment indicate that this novel calibration method needs only a few control points while the traditional calibration methods need much more control points to get the same accuracy. So the method could realize the on-line high-precision calibration of CCD camera for LAMOST.

  20. BXS Re-calibration

    SciTech Connect

    Welch, J; ,

    2010-11-24

    Early in the commissioning it was noticed by Cecile Limborg that the calibration of the BXS spectrometer magnet seemed to be different from the strength of the BX01/BX02 magnets. First the BX01/BX02 currents were adjusted to 135 MeV and the beam energy was adjusted to make the horizontal orbit flat. Then BX01/BX02 magnets were switched off and BXS was adjusted to make the horizontal orbit in the spectrometer line flat, without changing the energy of the beam. The result was that about 140-141 MeV were required on the BXS magnet. This measurement was repeated several times by others with the same results. It was not clear what was causing the error: magnet strength or layout. A position error of about 19 mm of the BXS magnet could explain the difference. Because there was a significant misalignment of the vacuum chamber in the BXS line, the alignment of the whole spectrometer line was checked. The vacuum chamber was corrected, but the magnets were found to be in the proper alignment. So we were left with one (or conceivably two) magnet calibration errors. Because BXS is a wedged shaped magnet, the bend angle depends on the horizontal position of the incoming beam. As mentioned, an offset of the beam position of 19 mm would increase or decrease the bend angle roughly by the ratio of 135/141. The figure of 19 mm is special and caused a considerable confusion during the design and measurement of the BXS magnet. This is best illustrated in Figure 1 which was taken out of the BXS Traveler document. The distance between the horizontal midplanes of the poles and the apex of the beam path was chosen to be 19 mm so the beam is close to the good field region throughout its entire path. Thus it seemed possible that there was an error that resulted in the beam not being on this trajectory, or conversely, that the magnetic measurements were done on the wrong trajectory and the magnet was then mis-calibrated. Mechanical measurements of the vacuum chamber made in the tunnel

  1. A proposed standard method for polarimetric calibration and calibration verification

    NASA Astrophysics Data System (ADS)

    Persons, Christopher M.; Jones, Michael W.; Farlow, Craig A.; Morell, L. Denise; Gulley, Michael G.; Spradley, Kevin D.

    2007-09-01

    Accurate calibration of polarimetric sensors is critical to reducing and analyzing phenomenology data, producing uniform polarimetric imagery for deployable sensors, and ensuring predictable performance of polarimetric algorithms. It is desirable to develop a standard calibration method, including verification reporting, in order to increase credibility with customers and foster communication and understanding within the polarimetric community. This paper seeks to facilitate discussions within the community on arriving at such standards. Both the calibration and verification methods presented here are performed easily with common polarimetric equipment, and are applicable to visible and infrared systems with either partial Stokes or full Stokes sensitivity. The calibration procedure has been used on infrared and visible polarimetric imagers over a six year period, and resulting imagery has been presented previously at conferences and workshops. The proposed calibration method involves the familiar calculation of the polarimetric data reduction matrix by measuring the polarimeter's response to a set of input Stokes vectors. With this method, however, linear combinations of Stokes vectors are used to generate highly accurate input states. This allows the direct measurement of all system effects, in contrast with fitting modeled calibration parameters to measured data. This direct measurement of the data reduction matrix allows higher order effects that are difficult to model to be discovered and corrected for in calibration. This paper begins with a detailed tutorial on the proposed calibration and verification reporting methods. Example results are then presented for a LWIR rotating half-wave retarder polarimeter.

  2. 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

  3. Two syringe spinal anesthesia technique for cesarean section: A controlled randomized study of a simple way to achieve more satisfactory block and less hypotension

    PubMed Central

    Keera, Amr Aly Ismail; Elnabtity, Ali Mohamed Ali

    2016-01-01

    Background: Multiple trials have been tried to prevent hypotension during spinal anesthesia. However, the drug choice and mode of administration is still a matter of debate. Objectives: To compare the outcome of spinal injection of hyperbaric bupivacaine and fentanyl separately to standard injection of mixed fentanyl with hyperbaric bupivacaine. Settings and Design: A randomized, controlled clinical trial. Patients and Methods: One hundred twenty-four parturient scheduled for elective cesarean section were randomly allocated into two groups, each 62 parturient: Group M received spinal anesthesia using 10 mg bupivacaine 0.5% premixed with 25 μg fentanyl in the same syringe and Group S received 25 μg fentanyl in one syringe and 10 mg bupivacaine 0.5% without barbotage in a second syringe. Results: Patients with intraoperative pain that was controllable without the need for a shift to general anesthesia was significantly lower in Group S (3.2%) than in Group M (16.1%). The frequency of hypotension was significantly lower in Group S compared to Group M (P < 0.05). Time till the onset of sensory block was nonsignificantly shorter with nonsignificantly higher mean level of maximal sensory block in Group S compared to Group M (P > 0.05). There was no significant difference in the time till occurrence of hypotension, duration of hypotension, mean dose of ephedrine used for the treatment of hypotension and frequency of patients developed itching between the groups (P > 0.05). Conclusion: Separate intrathecal injection of fentanyl and hyperbaric bupivacaine provided a significant improvement in the quality of sensory block and significant reduction of the frequency of hypotension compared to injection of mixed medications. PMID:27212767

  4. Comparison of TLD calibration methods for 192Ir dosimetry.

    PubMed

    Haworth, Annette; Butler, Duncan J; Wilfert, Lisa; Ebert, Martin A; Todd, Stephen P; Hayton, Anna J M; Kron, Tomas

    2013-01-01

    For the purpose of dose measurement using a high-dose rate (192)Ir source, four methods of thermoluminescent dosimeter (TLD) calibration were investigated. Three of the four calibration methods used the (192)Ir source. Dwell times were calculated to deliver 1 Gy to the TLDs irradiated either in air or water. Dwell time calculations were confirmed by direct measurement using an ionization chamber. The fourth method of calibration used 6 MV photons from a medical linear accelerator, and an energy correction factor was applied to account for the difference in sensitivity of the TLDs in (192)Ir and 6 MV. The results of the four TLD calibration methods are presented in terms of the results of a brachytherapy audit where seven Australian centers irradiated three sets of TLDs in a water phantom. The results were in agreement within estimated uncertainties when the TLDs were calibrated with the (192)Ir source. Calibrating TLDs in a phantom similar to that used for the audit proved to be the most practical method and provided the greatest confidence in measured dose. When calibrated using 6 MV photons, the TLD results were consistently higher than the (192)Ir-calibrated TLDs, suggesting this method does not fully correct for the response of the TLDs when irradiated in the audit phantom. PMID:23318392

  5. 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.

  6. A new polarimetric active radar calibrator and calibration technique

    NASA Astrophysics Data System (ADS)

    Tang, Jianguo; Xu, Xiaojian

    2015-10-01

    Polarimetric active radar calibrator (PARC) is one of the most important calibrators with high radar cross section (RCS) for polarimetry measurement. In this paper, a new double-antenna polarimetric active radar calibrator (DPARC) is proposed, which consists of two rotatable antennas with wideband electromagnetic polarization filters (EMPF) to achieve lower cross-polarization for transmission and reception. With two antennas which are rotatable around the radar line of sight (LOS), the DPARC provides a variety of standard polarimetric scattering matrices (PSM) through the rotation combination of receiving and transmitting polarization, which are useful for polarimatric calibration in different applications. In addition, a technique based on Fourier analysis is proposed for calibration processing. Numerical simulation results are presented to demonstrate the superior performance of the proposed DPARC and processing technique.

  7. Stability of Ertapenem 100 mg/mL in Manufacturer’s Glass Vials or Syringes at 4°C and 23°C

    PubMed Central

    Walker, Scott E; Law, Shirley; Perks, William; Iazzetta, John

    2015-01-01

    Background: Prophylactic administration of ertapenem as a single 1-g IV dose has been shown to reduce sepsis after prostate biopsy. Objective: To evaluate the stability of ertapenem after reconstitution with 0.9% sodium chloride to a final concentration of 100 mg/mL and storage in the manufacturer’s original glass vials or polypropylene syringes. Methods: On study day 0, 100 mg/mL solutions of ertapenem were retained in the manufacturer’s glass vials or packaged in polypropylene syringes and stored at 4°C or 23°C without protection from fluorescent room light. Samples were assayed periodically over 18 days using a validated, stability-indicating liquid chromatographic method with ultra-violet detection. A beyond-use date was determined as the time for the concentration to decline to 90% of the initial (day 0) concentration, based on the fastest degradation rate, with 95% confidence. Results: Reconstituted solutions stored in the manufacturer’s glass vials or polypropylene syringes exhibited a first-order degradation rate, such that 10% of the initial concentration was lost in the first 2.5 days when stored at 4°C or within the first 6.75 h when stored at room temperature (23°C). Analysis of variance showed differences in the percentage remaining due to temperature (p < 0.001) and study day (p < 0.001) but not type of container (p = 0.98). When a 95% CI for the degradation rate was calculated and used to determine a beyond-use date, it was established that more than 90% of the initial concentration would remain for 2.35 days at 4°C and for 0.23 day (about 5 h, 30 min) at room temperature. Conclusions: A 100 mg/mL ertapenem solution stored in the manufacturer’s glass vial or a polypropylene syringe will retain more than 90.5% of the initial concentration when stored for 48 h at 4°C and for an additional 1 h at 23°C. PMID:25964683

  8. Radiometric calibration to consider in quantitative clinical fluorescence imaging measurements

    NASA Astrophysics Data System (ADS)

    Litorja, M.; Urbas, A.; Zong, Y.

    2015-03-01

    The fluorescent light detected by a clinical imager is assumed to be proportional only to the amount of fluorescent substance present in the sample and the level of excitation. Unfortunately, there are many factors that can add or subtract to the light signal directly attributable to the desired fluorescence emission, especially with fluorescence from inside the body imaged remotely. The quantification of fluorescence emission is feasible by calibrating the imager using international system of units (SI)-traceable physical and material calibration artifacts such that the detector's digital numbers (DN) can be converted to radiometric units. Here we discuss three calibration methods for quantitative clinical fluorescence imaging systems.

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

  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. ENVISAT-1 MWR: calibration targets and preflight calibration

    NASA Astrophysics Data System (ADS)

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

    1998-12-01

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

  12. 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.

  13. Photometric calibration of planetary photographs

    NASA Technical Reports Server (NTRS)

    Beebe, R. F.

    1976-01-01

    The basic data and approach for calibrating photographic plates obtained with the 61 cm telescope at the Tortugas Mountain Station of New Mexico State University are summarized. Since this is the fundamental calibration of planetary data it is of use to all in-house users as well as other individuals who use the data.

  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. 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.

  16. Establishing a NORM based radiation calibration facility.

    PubMed

    Wallace, J

    2016-05-01

    An environmental radiation calibration facility has been constructed by the Radiation and Nuclear Sciences unit of Queensland Health at the Forensic and Scientific Services Coopers Plains campus in Brisbane. This facility consists of five low density concrete pads, spiked with a NORM source, to simulate soil and effectively provide a number of semi-infinite uniformly distributed sources for improved energy response calibrations of radiation equipment used in NORM measurements. The pads have been sealed with an environmental epoxy compound to restrict radon loss and so enhance the quality of secular equilibrium achieved. Monte Carlo models (MCNP),used to establish suitable design parameters and identify appropriate geometric correction factors linking the air kerma measured above these calibration pads to that predicted for an infinite plane using adjusted ICRU53 data, are discussed. Use of these correction factors as well as adjustments for cosmic radiation and the impact of surrounding low levels of NORM in the soil, allows for good agreement between the radiation fields predicted and measured above the pads at both 0.15 m and 1 m. PMID:26921707

  17. 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.

  18. TIME CALIBRATED OSCILLOSCOPE SWEEP CIRCUIT

    DOEpatents

    Smith, V.L.; Carstensen, H.K.

    1959-11-24

    An improved time calibrated sweep circuit is presented, which extends the range of usefulness of conventional oscilloscopes as utilized for time calibrated display applications in accordance with U. S. Patent No. 2,832,002. Principal novelty resides in the provision of a pair of separate signal paths, each of which is phase and amplitude adjustable, to connect a high-frequency calibration oscillator to the output of a sawtooth generator also connected to the respective horizontal deflection plates of an oscilloscope cathode ray tube. The amplitude and phase of the calibration oscillator signals in the two signal paths are adjusted to balance out feedthrough currents capacitively coupled at high frequencies of the calibration oscillator from each horizontal deflection plate to the vertical plates of the cathode ray tube.

  19. Local hadron calibration with ATLAS

    NASA Astrophysics Data System (ADS)

    Giovannini, Paola; ATLAS Liquid Argon Calorimeter Group

    2011-04-01

    The method of Local Hadron Calibration is used in ATLAS as one of the two major calibration schemes for the reconstruction of jets and missing transverse energy. The method starts from noise suppressed clusters and corrects them for non-compensation effects and for losses due to noise threshold and dead material. Jets are reconstructed using the calibrated clusters and are then corrected for out of cone effects. The performance of the corrections applied to the calorimeter clusters is tested with detailed GEANT4 information. Results obtained with this procedure are discussed both for single pion simulations and for di-jet simulations. The calibration scheme is validated on data, by comparing the calibrated cluster energy in data with Mote Carlo simulations. Preliminary results obtained with GeV collision data are presented. The agreement between data and Monte Carlo is within 5% for the final cluster scale.

  20. 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.