Science.gov

Sample records for agency reference method

  1. 40 CFR 1508.24 - Referring agency.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Referring agency. 1508.24 Section 1508.24 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.24... or environmental quality. ...

  2. 40 CFR 1508.24 - Referring agency.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Referring agency. 1508.24 Section 1508.24 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.24... after a determination that the matter is unsatisfactory from the standpoint of public health or...

  3. 40 CFR 1508.24 - Referring agency.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Referring agency. 1508.24 Section 1508.24 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.24... after a determination that the matter is unsatisfactory from the standpoint of public health or...

  4. 40 CFR 1508.24 - Referring agency.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Referring agency. 1508.24 Section 1508.24 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.24... after a determination that the matter is unsatisfactory from the standpoint of public health or...

  5. 40 CFR 60.396 - Reference methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Reference methods and procedures. 60.396 Section 60.396 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Automobile...

  6. 40 CFR 60.396 - Reference methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Reference methods and procedures. 60.396 Section 60.396 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Automobile...

  7. 40 CFR 60.396 - Reference methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Reference methods and procedures. 60.396 Section 60.396 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Automobile...

  8. 75 FR 22126 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-27

    ... AGENCY Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods: Designation of One New Equivalent Method AGENCY: Environmental Protection Agency. ACTION: Notice of the designation of one new equivalent method for monitoring ambient air quality. SUMMARY: Notice is hereby...

  9. 76 FR 62402 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-07

    ... AGENCY Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods; Designation of One New Equivalent Method AGENCY: Environmental Protection Agency. ACTION: Notice of the..., Research Triangle Park, North Carolina 27711. Designation of this new equivalent method is intended...

  10. An Overview of the Smart Sensor Inter-agency Reference Testbench (SSIART)

    NASA Astrophysics Data System (ADS)

    Wagner, R. S.; Dufour, J.; Braham, S. P.; Barton, R. J.

    In this paper, we present an overview of a proposed collaboration between the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA), which is designed to facilitate the introduction of commercial-off-the-shelf (COTS) radios for smart-sensing applications into international spaceflight programs and projects. The proposed work will produce test hardware reference designs, test software reference architectures and example implementations, test plans in reference test environments, and test results, all of which will be shared between the agencies and documented for future use by mission planners. The proposed collaborative structure together with all of the anticipated tools and results produced under the effort is collectively referred to as the Smart Sensor Inter-agency Reference Testbench or SSIART. It is intended to provide guidance in technology selection and in increasing the related readiness levels of projects and missions as well as the space industry.

  11. An Overview of the Smart Sensor Inter-Agency Reference Testbench (SSIART)

    NASA Technical Reports Server (NTRS)

    Wagner, Raymond S.; Braham, Stephen P.; Dufour, Jean-Francois; Barton, Richard J.

    2012-01-01

    In this paper, we present an overview of a proposed collaboration between the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA), which is designed to facilitate the introduction of commercial-off-the-shelf (COTS) radios for smart-sensing applications into international spaceflight programs and projects. The proposed work will produce test hardware reference designs, test software reference architectures and example implementations, test plans in reference test environments, and test results, all of which will be shared between the agencies and documented for future use by mission planners. The proposed collaborative structure together with all of the anticipated tools and results produced under the effort is collectively referred to as the Smart Sensor Inter-agency Reference Testbench or SSIART. It is intended to provide guidance in technology selection and in increasing the related readiness levels of projects and missions as well as the space industry.

  12. An Overview of the Smart Sensor Inter-Agency Reference Testbench (SSIART)

    NASA Technical Reports Server (NTRS)

    Wagner, Raymond S.; Braham, Stephen P.; Dufour, Jean-Francois; Barton, Richard J.

    2012-01-01

    In this paper, we present an overview of a proposed collaboration between the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA), which is designed to facilitate the introduction of commercial-off-the-shelf (COTS) radios for smart-sensing applications into international spaceflight programs and projects. The proposed work will produce test hardware reference designs, test software reference architectures and example implementations, test plans in reference test environments, and test results, all of which will be shared between the agencies and documented for future use by mission planners. The proposed collaborative structure together with all of the anticipated tools and results produced under the effort is collectively referred to as the Smart Sensor Inter-agency Reference Testbench or SSIART. It is intended to provide guidance in technology selection and in increasing the related readiness levels of projects and missions as well as the space industry.

  13. 77 FR 32632 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-01

    ... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent... of lead (Pb) in the ambient air. FOR FURTHER INFORMATION CONTACT: Robert Vanderpool, Human Exposure... CFR Part 53, the EPA evaluates various methods for monitoring the concentrations of those ambient...

  14. 77 FR 60985 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New Equivalent Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ... for Air Pollution Measurement Systems, Volume I,'' EPA/600/R-94/038a and ``Quality Assurance Handbook for Air Pollution Measurement Systems, Volume II, Ambient Air Quality Monitoring Program'' EPA-454/B... AGENCY Ambient Air Monitoring Reference and Equivalent Methods: Designation of Three New...

  15. 31 CFR 5.15 - How will Treasury entities refer Treasury debts to private collection agencies?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false How will Treasury entities refer Treasury debts to private collection agencies? 5.15 Section 5.15 Money and Finance: Treasury Office of the Secretary of the Treasury TREASURY DEBT COLLECTION Procedures To Collect Treasury Debts § 5.15 How...

  16. 15 CFR 19.15 - How will Commerce entities refer Commerce debts to private collection agencies?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false How will Commerce entities refer Commerce debts to private collection agencies? 19.15 Section 19.15 Commerce and Foreign Trade Office of the Secretary of Commerce COMMERCE DEBT COLLECTION Procedures To Collect Commerce Debts § 19.15 How...

  17. Multi-reference vibration correlation methods

    SciTech Connect

    Pfeiffer, Florian; Rauhut, Guntram

    2014-02-14

    State-specific vibration correlation methods beyond the vibrational multi-configuration self-consistent field (VMCSCF) approximation have been developed, which allow for the accurate calculation of state energies for systems suffering from strong anharmonic resonances. Both variational multi-reference configuration interaction approaches and an implementation of approximate 2nd order vibrational multi-reference perturbation theory are presented. The variational approach can be significantly accelerated by a configuration selection scheme, which leads to negligible deviations in the final results. Relaxation effects due to the partitioning of the correlation space and the performance of a VMCSCF modal basis in contrast to a standard modal basis obtained from vibrational self-consistent field theory have been investigated in detail. Benchmark calculations based on high-level potentials are provided for the propargyl cation and cis-diazene.

  18. 41 CFR 102-118.185 - When buying freight transportation, must my agency reference the applicable contract or tender on...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....185 When buying freight transportation, must my agency reference the applicable contract or tender on... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false When buying freight transportation, must my agency reference the applicable contract or tender on the bill of lading (including a...

  19. 41 CFR 102-118.185 - When buying freight transportation, must my agency reference the applicable contract or tender on...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ....185 When buying freight transportation, must my agency reference the applicable contract or tender on... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false When buying freight transportation, must my agency reference the applicable contract or tender on the bill of lading (including a...

  20. Nitrate loss associated with Federal Reference Method

    NASA Astrophysics Data System (ADS)

    Jin, L.; Serve, A.; Brown, N. J.

    2014-12-01

    The 24-h PM2.5 mass, measured by the Federal Reference Method (FRM) designated by EPA, reports the bulk PM2.5 mass retained on a single channel sampler with Teflon or Quartz filters. Semivolatile species such as nitrate can be lost from the Teflon filter during sampling and equilibration processes, and the FRM measurements may not reflect true ambient concentrations of total PM2.5. Consequently, FRM PM2.5 can be problematic when used for evaluating the fidelity of air quality models, especially for domains where particulate nitrate is a dominant contributor. In order to account for this discrepancy, a thermodynamic adjustment method was developed by EPA to determine the retained nitrate based upon the temperature (T) and relative humidity (RH). The nitrate adjustment method was evaluated for the eastern US where summertime is characterized by hot and humid weather and sulfate particles are the dominant inorganic contributor. Potential differences exist for applications to California due to its different PM2.5 composition and meteorology. In this study we, (1) evaluate EPA's nitrate adjustment method for California where particulate nitrate is a major contributor to total PM2.5 mass and (2) apply this method to adjusting simulated PM2.5 by the Community Multiscale Air Quality Model(CMAQ) over the California domain. The adjusted CMAQ outputs are then compared to the observed total PM2.5. The positive biases between CMAQ and observed PM2.5 can be largely explained by evaporative loss of nitrate on filters.

  1. Telepsychiatry with child welfare families referred to a family service agency.

    PubMed

    Keilman, Peggy

    2005-02-01

    A telepsychology and telepsychiatry service, using ISDN interactive video H.320, providing psychological consultations for the Family Resource Center in Farmington, New Mexico, was evaluated. During the first year of service, 56 individuals participated including University of New Mexico staff, Family Resource Center staff and clients. Consultations involved children from families referred by the Children, Youth and Family Department (CYFD) in New Mexico. Telemedicine was used in some child abuse cases. This study investigated whether the quality and acceptance of telemedicine consultations were comparable to face-to-face interactions in a group referred by a state child welfare agency. Participants received formal written consultation reports after the video conferencing sessions, which included a number of recommendations. Participants were asked to complete an anonymous questionnaire to rate various aspects of videoconferencing. The participants rated the university staff as involved, enjoyed the Family Resource Center staff's presence, felt the procedure was useful for evaluation purposes, found the format allowed for discussions of problems, and felt that the format was useful when compared to face-to-face consultations. The participants also said they had followed up on many of the recommendations. Videoconferencing appears to be a viable approach for providing consultation for families referred by a state child welfare agency. Several participants rated the session as both educational and consultative compared to simply therapeutic.

  2. Teaching Reference by the Smorgasbord Method.

    ERIC Educational Resources Information Center

    Sable, Martin H.

    1984-01-01

    Describes in detail six component features of teaching reference: lectures by instructor; assigned readings for class discussion; student reports; library "lab" sessions; case-study discussion; and speakers and library visits. Importance of planning and time-scheduling, comparative value of each component, grading, and element of…

  3. Evaluation of Alternatives to the Ontario Hydro Method as a Reference Method for CAMR

    SciTech Connect

    Dennis L. Laudal

    2007-03-31

    In June 2005, the U.S. Environmental Protection Agency (EPA) finalized the Clean Air Mercury Rule (CAMR). As part of the rule, all coal-fired power plants will be required to do continuous mercury measurements. To complete the required relative accuracy test assessment (RATA), the only reference methods allowed are the wet-chemistry methods: the Ontario Hydro (OH) mercury speciation method (ASTM International D6784-02) and EPA Method 29. Either method will be a challenge and expensive. It would be much more desirable to use an instrumental reference method (IRM) or use sorbent traps as a reference method so that the results can be obtained quickly and cheaply. This report presents the results from testing at Reliant Energy, Inc.'s, Portland Station. The project was designed to compare mercury concentrations measured using sorbent traps to those obtained using the OH method. The tests were done using a RATA scenario and at three different conditions. In addition, as part of the project, limited IRM testing was also completed. The results from the testing show that the sorbent traps compared very well with the OH method and, therefore, must be considered as a potential reference method. Although the IRM testing using manual injection of elemental and oxidized mercury for dynamic spiking showed some promise, it was clear that additional testing was needed. However, this method of dynamic spiking may not be acceptable to EPA, as it does not consider vapor pressure curves for elemental mercury a National Institute of Standards Technology traceable standard.

  4. Child Geopolitical Agency: A Mixed Methods Case Study

    ERIC Educational Resources Information Center

    Habashi, Janette; Worley, Jody

    2009-01-01

    This study examines the geopolitical agency of Palestinian children. Mixed methodology was used to identify the etiologies contributing to processes of political socialization. Both qualitative and qualitative methods are equally distributed throughout this research. Focus groups and interviews with 12 Palestinian children, aged 10 to 13 years,…

  5. Child Geopolitical Agency: A Mixed Methods Case Study

    ERIC Educational Resources Information Center

    Habashi, Janette; Worley, Jody

    2009-01-01

    This study examines the geopolitical agency of Palestinian children. Mixed methodology was used to identify the etiologies contributing to processes of political socialization. Both qualitative and qualitative methods are equally distributed throughout this research. Focus groups and interviews with 12 Palestinian children, aged 10 to 13 years,…

  6. 10 CFR 434.505 - Reference building method.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505...

  7. 10 CFR 434.505 - Reference building method.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505...

  8. 10 CFR 434.505 - Reference building method.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505...

  9. 10 CFR 434.505 - Reference building method.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505.1...

  10. 10 CFR 434.505 - Reference building method.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Reference building method. 434.505 Section 434.505 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CODE FOR NEW FEDERAL COMMERCIAL AND MULTI-FAMILY HIGH RISE RESIDENTIAL BUILDINGS Building Energy Cost Compliance Alternative § 434.505 Reference building method. 505...

  11. 40 CFR 75.22 - Reference test methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... basis (or from a wet basis to a dry basis) and shall be used when relative accuracy test audits of... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Reference test methods. 75.22 Section...) CONTINUOUS EMISSION MONITORING Operation and Maintenance Requirements § 75.22 Reference test methods. (a)...

  12. Assessment of potential risk levels associated with U.S. Environmental Protection Agency reference values.

    PubMed Central

    Castorina, Rosemary; Woodruff, Tracey J

    2003-01-01

    The U.S. Environmental Protection Agency (U.S. EPA) generally uses reference doses (RfDs) or reference concentrations (RfCs) to assess risks from exposure to toxic substances for noncancer health end points. RfDs and RfCs are supposed to represent lifetime inhalation or ingestion exposure with minimal appreciable risk, but they do not include information about the estimated risk from exposures equal to the RfD/RfC. We used results from benchmark dose modeling approaches recently adopted for use in developing RfDs/RfCs to estimate the risk levels associated with exposures at the RfD/RfC. We searched the U.S. EPA Integrated Risk Information System (IRIS) database and identified 11 chemicals with oral RfDs and 12 chemicals with inhalation RfCs that used benchmark dose modeling. For assessments with sufficient model information, we found that 16 of 21 (76%) of the dose-response models were linear or supralinear. We estimated the risk from exposures at the established RfDs and RfCs for these chemicals using a linear dose-response curve to characterize risk below the observed data. Risk estimates ranged from 1 in 10,000 to 5 in 1,000 for exposures at the RfDs, and from 1 in 10,000 to 3 in 1,000 for exposures at the RfCs. Risk estimates for exposures at the RfD/RfC values derived from sublinear dose-response curves ranged from 3 in 1,000,000,000 to 8 in 10,000. Twenty-four percent of reference values corresponded to estimated risk levels greater than 1 in 1,000; 10 of 14 assessments had points of departure greater than the no-observed-adverse-effect levels. For policy development regarding management of cancer risks, the U.S. EPA often uses 1 in 1,000,000 as a de minimis risk level. Although noncancer outcomes may in some instances be reversible and considered less severe than cancer, our findings call into question the assumption that established RfD and RfC values represent negligibly small risk levels. PMID:12896853

  13. Reference intervals data mining: no longer a probability paper method.

    PubMed

    Katayev, Alexander; Fleming, James K; Luo, Dajie; Fisher, Arren H; Sharp, Thomas M

    2015-01-01

    To describe the application of a data-mining statistical algorithm for calculation of clinical laboratory tests reference intervals. Reference intervals for eight different analytes and different age and sex groups (a total of 11 separate reference intervals) for tests that are unlikely to be ordered during routine screening of disease-free populations were calculated using the modified algorithm for data mining of test results stored in the laboratory database and compared with published peer-reviewed studies that used direct sampling. The selection of analytes was based on the predefined criteria that include comparability of analytical methods with a statistically significant number of observations. Of the 11 calculated reference intervals, having upper and lower limits for each, 21 of 22 reference interval limits were not statistically different from the reference studies. The presented statistical algorithm is shown to be an accurate and practical tool for reference interval calculations. Copyright© by the American Society for Clinical Pathology.

  14. Factors influencing the accuracy of the national reference system total cholesterol reference method.

    PubMed

    Bernert, J T; Akins, J R; Cooper, G R; Poulose, A K; Myers, G L; Sampson, E J

    1991-12-01

    Previous comparisons between the Reference and Definitive Methods for measuring serum cholesterol have demonstrated a small but persistent positive bias in the Reference Method, averaging about +1.6%. Here we describe the results of further investigations designed to better characterize the nature of this bias. Analysis of a well-characterized model serum sample (SRM 909) suggests that more than half of the difference in cholesterol values determined by the two methods is the result of small contributions from cholesterol precursor sterols and phytosterols, which are also measured for the Reference Method. An additional significant contribution may be from cholesterol oxidation products, particularly 7-hydroxycholesterol isomers, which are active in the Liebermann-Burchard reaction. The 7-hydroxycholesterol in SRM 909, most of which appeared to be already present in the serum rather than formed during saponification, may account for as much as 20% of the observed difference between the methods. Contributions from other possible sources, including impurities in the cholesterol standard and incomplete saponification of cholesteryl esters, are very small. Because the observed bias is both quite small and consistent among samples, the cholesterol Reference Method continues to meet all of the requirements generally expected for a dependable and effective Reference Method.

  15. 41 CFR 102-118.185 - When buying freight transportation, must my agency reference the applicable contract or tender on...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false When buying freight....185 When buying freight transportation, must my agency reference the applicable contract or tender on... tender when buying transportation on a bill of lading (including GBLs). However, the referenced...

  16. 41 CFR 102-118.185 - When buying freight transportation, must my agency reference the applicable contract or tender on...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false When buying freight....185 When buying freight transportation, must my agency reference the applicable contract or tender on... tender when buying transportation on a bill of lading (including GBLs). However, the referenced...

  17. 41 CFR 102-118.185 - When buying freight transportation, must my agency reference the applicable contract or tender on...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false When buying freight....185 When buying freight transportation, must my agency reference the applicable contract or tender on... tender when buying transportation on a bill of lading (including GBLs). However, the referenced...

  18. 41 CFR 102-118.190 - When buying passenger transportation must my agency reference the applicable contract?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... applicable contract on a GTR or passenger transportation document (e.g., ticket). ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false When buying passenger transportation must my agency reference the applicable contract? 102-118.190 Section 102-118.190 Public...

  19. 41 CFR 102-118.190 - When buying passenger transportation must my agency reference the applicable contract?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... applicable contract on a GTR or passenger transportation document (e.g., ticket). ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false When buying passenger transportation must my agency reference the applicable contract? 102-118.190 Section 102-118.190 Public...

  20. 41 CFR 102-118.190 - When buying passenger transportation must my agency reference the applicable contract?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... applicable contract on a GTR or passenger transportation document (e.g., ticket). ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false When buying passenger transportation must my agency reference the applicable contract? 102-118.190 Section 102-118.190 Public...

  1. 41 CFR 102-118.190 - When buying passenger transportation must my agency reference the applicable contract?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... applicable contract on a GTR or passenger transportation document (e.g., ticket). ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false When buying passenger transportation must my agency reference the applicable contract? 102-118.190 Section 102-118.190 Public...

  2. 41 CFR 102-118.190 - When buying passenger transportation must my agency reference the applicable contract?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... applicable contract on a GTR or passenger transportation document (e.g., ticket). ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false When buying passenger transportation must my agency reference the applicable contract? 102-118.190 Section 102-118.190 Public...

  3. Phase measurement profilometry based on a virtual reference plane method

    NASA Astrophysics Data System (ADS)

    Ren, Hongbing; Lee, Jinlong; Gao, Xiaorong

    2016-09-01

    In Phase Measurement Profilometry(PMP), the setting of the reference plane plays an important role. It is a critical step to capture the grating fringe projected onto the reference plane in PMP. However, it is sometimes difficult to choose and place the reference plane in practical applications. In this paper, a virtual reference plane is introduced into PMP, with which 3D measurement can be realized without using the physical reference plane. The virtual reference plane is generated through extracting a partial area of the deformed fringe image that corresponds to a planar region and employing the interpolation algorithm. The method is proved theoretically through simulation experiments, providing a new suggestion for actual measurement by PMP.

  4. Validation of three new methods for determination of metal emissions using a modified Environmental Protection Agency Method 301.

    PubMed

    Yanca, Catherine A; Barth, Douglas C; Petterson, Krag A; Nakanishi, Michael P; Cooper, John A; Johnsen, Bruce E; Lambert, Richard H; Bivins, Daniel G

    2006-12-01

    Three new methods applicable to the determination of hazardous metal concentrations in stationary source emissions were developed and evaluated for use in U.S. Environmental Protection Agency (EPA) compliance applications. Two of the three independent methods, a continuous emissions monitor-based method (Xact) and an X-ray-based filter method (XFM), are used to measure metal emissions. The third method involves a quantitative aerosol generator (QAG), which produces a reference aerosol used to evaluate the measurement methods. A modification of EPA Method 301 was used to validate the three methods for As, Cd, Cr, Pb, and Hg, representing three hazardous waste combustor Maximum Achievable Control Technology (MACT) metal categories (low volatile, semivolatile, and volatile). The modified procedure tested the methods using more stringent criteria than EPA Method 301; these criteria included accuracy, precision, and linearity. The aerosol generation method was evaluated in the laboratory by comparing actual with theoretical aerosol concentrations. The measurement methods were evaluated at a hazardous waste combustor (HWC) by comparing measured with reference aerosol concentrations. The QAG, Xact, and XFM met the modified Method 301 validation criteria. All three of the methods demonstrated precisions and accuracies on the order of 5%. In addition, correlation coefficients for each method were on the order of 0.99, confirming the methods' linear response and high precision over a wide range of concentrations. The measurement methods should be applicable to emissions from a wide range of sources, and the reference aerosol generator should be applicable to additional analytes. EPA recently approved an alternative monitoring petition for an HWC at Eli Lilly's Tippecanoe site in Lafayette, IN, in which the Xact is used for demonstrating compliance with the HWC MACT metal emissions (low volatile, semivolatile, and volatile). The QAG reference aerosol generator was approved as

  5. The agencies method for coalition formation in experimental games

    PubMed Central

    Nash, John F.; Nagel, Rosemarie; Ockenfels, Axel; Selten, Reinhard

    2012-01-01

    In society, power is often transferred to another person or group. A previous work studied the evolution of cooperation among robot players through a coalition formation game with a non-cooperative procedure of acceptance of an agency of another player. Motivated by this previous work, we conduct a laboratory experiment on finitely repeated three-person coalition formation games. Human players with different strength according to the coalition payoffs can accept a transfer of power to another player, the agent, who then distributes the coalition payoffs. We find that the agencies method for coalition formation is quite successful in promoting efficiency. However, the agent faces a tension between short-term incentives of not equally distributing the coalition payoff and the long-term concern to keep cooperation going. In a given round, the strong player in our experiment often resolves this tension approximately in line with the Shapley value and the nucleolus. Yet aggregated over all rounds, the payoff differences between players are rather small, and the equal division of payoffs predicts about 80% of all groups best. One reason is that the voting procedure appears to induce a balance of power, independent of the individual player's strength: Selfish subjects tend to be voted out of their agency and are further disciplined by reciprocal behaviors. PMID:23175792

  6. The agencies method for coalition formation in experimental games.

    PubMed

    Nash, John F; Nagel, Rosemarie; Ockenfels, Axel; Selten, Reinhard

    2012-12-11

    In society, power is often transferred to another person or group. A previous work studied the evolution of cooperation among robot players through a coalition formation game with a non-cooperative procedure of acceptance of an agency of another player. Motivated by this previous work, we conduct a laboratory experiment on finitely repeated three-person coalition formation games. Human players with different strength according to the coalition payoffs can accept a transfer of power to another player, the agent, who then distributes the coalition payoffs. We find that the agencies method for coalition formation is quite successful in promoting efficiency. However, the agent faces a tension between short-term incentives of not equally distributing the coalition payoff and the long-term concern to keep cooperation going. In a given round, the strong player in our experiment often resolves this tension approximately in line with the Shapley value and the nucleolus. Yet aggregated over all rounds, the payoff differences between players are rather small, and the equal division of payoffs predicts about 80% of all groups best. One reason is that the voting procedure appears to induce a balance of power, independent of the individual player's strength: Selfish subjects tend to be voted out of their agency and are further disciplined by reciprocal behaviors.

  7. Evaluation of alternative methods for estimating reference evapotranspiration

    USDA-ARS?s Scientific Manuscript database

    Evapotranspiration is an important component in water-balance and irrigation scheduling models. While the FAO-56 Penman-Monteith method has become the de facto standard for estimating reference evapotranspiration (ETo), it is a complex method requiring several weather parameters. Required weather ...

  8. Comparison of two reference methods for detemining cotton fiber moisture

    USDA-ARS?s Scientific Manuscript database

    Moisture is an important quality and processing property for the cotton industry. The standard reference method for determining the moisture content in cotton fiber is the ASTM oven method (gravimetric weight loss). Several concerns have expressed on its ability to measure the actual moisture cont...

  9. 40 CFR 53.16 - Supersession of reference methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the Administrator specify a new reference method, or a new measurement principle and calibration... method or a new measurement principle and calibration procedure. (2) The potential economic consequences... quality monitoring programs that might result from such action. (c) An applicant who wishes the...

  10. 40 CFR 53.16 - Supersession of reference methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the Administrator specify a new reference method, or a new measurement principle and calibration... method or a new measurement principle and calibration procedure. (2) The potential economic consequences... quality monitoring programs that might result from such action. (c) An applicant who wishes the...

  11. DNA-Based Methods in the Immunohematology Reference Laboratory

    PubMed Central

    Denomme, Gregory A

    2010-01-01

    Although hemagglutination serves the immunohematology reference laboratory well, when used alone, it has limited capability to resolve complex problems. This overview discusses how molecular approaches can be used in the immunohematology reference laboratory. In order to apply molecular approaches to immunohematology, knowledge of genes, DNA-based methods, and the molecular bases of blood groups are required. When applied correctly, DNA-based methods can predict blood groups to resolve ABO/Rh discrepancies, identify variant alleles, and screen donors for antigen-negative units. DNA-based testing in immunohematology is a valuable tool used to resolve blood group incompatibilities and to support patients in their transfusion needs. PMID:21257350

  12. Matching reference materials with AOAC International methods of analysis.

    PubMed

    Wolf, W R; DeVries, J; Ikins, W

    2001-10-01

    Proper implementation and use of validated analytical methodology with use of appropriate reference materials (RM) is a preferred means of helping to ensure equivalent analytical method performance in diverse laboratories. Choice of an appropriate RM that not only matches the analyte and matrix of the required determination, but also has been demonstrated to be within the applicability of a specific analytical method, are key factors. In response to numerous requests since its founding in 1993, the Technical Division on Reference Materials (TDRM), AOAC International is implementing a program for recognizing the matching of specific reference materials to specific AOAC methods of analysis. This recognition is accomplished by means of a thorough peer-reviewed selection system, under the auspices of the AOAC official methods board and the executive committee of the TDRM. Potential RM/method matching (RM/MM) proposals will be submitted to an RM/MM committee. After technical review of the suitability of the proposed RM by the RM/MM committee, acceptable matches are recommended for review by the current AOAC process responsible for review and recognition of new methods and modifications to existing AOAC methods of analysis. Several trial matches have been used to develop and test this system. The end product of this effort will ultimately be made available as either a stand-alone document, a section of the AOAC Official Methods of Analysis, or a site within the AOAC web site listing recognized matches.

  13. Reference noise method of removing powerline noise from recorded signals.

    PubMed

    Jiruska, Premysl; Cmejla, Roman; Powell, Andrew D; Chang, Wei-Chih; Vreugdenhil, Martin; Jefferys, John G R

    2009-10-30

    Powerline contamination of recorded signals represents a major source of noise in electrophysiology and impairs the use of recordings for research. In this article we present simple and effective method for cancelling 50 Hz (or 60 Hz) noise using a reference noise signal and average noise cycle subtraction. This method is capable of reliably removing not only the fundamental powerline frequency but also its harmonic frequencies. The efficiency of this method appears to be superior to other commonly used methods such as notch filtering or adaptive filtering. Our experience and results show that this method can be efficiently used with very low signal-to-noise ratios, while preserving original signal waveform.

  14. Certified reference materials and reference methods for nuclear safeguards and security.

    PubMed

    Jakopič, R; Sturm, M; Kraiem, M; Richter, S; Aregbe, Y

    2013-11-01

    Confidence in comparability and reliability of measurement results in nuclear material and environmental sample analysis are established via certified reference materials (CRMs), reference measurements, and inter-laboratory comparisons (ILCs). Increased needs for quality control tools in proliferation resistance, environmental sample analysis, development of measurement capabilities over the years and progress in modern analytical techniques are the main reasons for the development of new reference materials and reference methods for nuclear safeguards and security. The Institute for Reference Materials and Measurements (IRMM) prepares and certifices large quantities of the so-called "large-sized dried" (LSD) spikes for accurate measurement of the uranium and plutonium content in dissolved nuclear fuel solutions by isotope dilution mass spectrometry (IDMS) and also develops particle reference materials applied for the detection of nuclear signatures in environmental samples. IRMM is currently replacing some of its exhausted stocks of CRMs with new ones whose specifications are up-to-date and tailored for the demands of modern analytical techniques. Some of the existing materials will be re-measured to improve the uncertainties associated with their certified values, and to enable laboratories to reduce their combined measurement uncertainty. Safeguards involve the quantitative verification by independent measurements so that no nuclear material is diverted from its intended peaceful use. Safeguards authorities pay particular attention to plutonium and the uranium isotope (235)U, indicating the so-called 'enrichment', in nuclear material and in environmental samples. In addition to the verification of the major ratios, n((235)U)/n((238)U) and n((240)Pu)/n((239)Pu), the minor ratios of the less abundant uranium and plutonium isotopes contain valuable information about the origin and the 'history' of material used for commercial or possibly clandestine purposes, and

  15. MOISTURE IN COTTON BY THE KARL FISCHER TITRATION REFERENCE METHOD

    USDA-ARS?s Scientific Manuscript database

    Moisture is a critical parameter that influences many aspects of cotton fiber from harvesting and ginning to various fiber properties. Because of their importance, reference moisture methods that are more accurate than the existing oven-drying techniques and relatively easy to generate results are ...

  16. Reduced-reference image quality assessment using moment method

    NASA Astrophysics Data System (ADS)

    Yang, Diwei; Shen, Yuantong; Shen, Yongluo; Li, Hongwei

    2016-10-01

    Reduced-reference image quality assessment (RR IQA) aims to evaluate the perceptual quality of a distorted image through partial information of the corresponding reference image. In this paper, a novel RR IQA metric is proposed by using the moment method. We claim that the first and second moments of wavelet coefficients of natural images can have approximate and regular change that are disturbed by different types of distortions, and that this disturbance can be relevant to human perceptions of quality. We measure the difference of these statistical parameters between reference and distorted image to predict the visual quality degradation. The introduced IQA metric is suitable for implementation and has relatively low computational complexity. The experimental results on Laboratory for Image and Video Engineering (LIVE) and Tampere Image Database (TID) image databases indicate that the proposed metric has a good predictive performance.

  17. Infrared image quality evaluation method without reference image

    NASA Astrophysics Data System (ADS)

    Yue, Song; Ren, Tingting; Wang, Chengsheng; Lei, Bo; Zhang, Zhijie

    2013-09-01

    Since infrared image quality depends on many factors such as optical performance and electrical noise of thermal imager, image quality evaluation becomes an important issue which can conduce to both image processing afterward and capability improving of thermal imager. There are two ways of infrared image quality evaluation, with or without reference image. For real-time thermal image, the method without reference image is preferred because it is difficult to get a standard image. Although there are various kinds of methods for evaluation, there is no general metric for image quality evaluation. This paper introduces a novel method to evaluate infrared image without reference image from five aspects: noise, clarity, information volume and levels, information in frequency domain and the capability of automatic target recognition. Generally, the basic image quality is obtained from the first four aspects, and the quality of target is acquired from the last aspect. The proposed method is tested on several infrared images captured by different thermal imagers. Calculate the indicators and compare with human vision results. The evaluation shows that this method successfully describes the characteristics of infrared image and the result is consistent with human vision system.

  18. Circuit and method for producing a flexible reference voltage

    NASA Technical Reports Server (NTRS)

    Thornton, Roger D. (Inventor)

    1993-01-01

    A flexible reference voltage circuit includes a circuit for producing a first digital signal representative of a range of reference voltage levels; a circuit for producing a second digital signal representative of a selected reference voltage level within the range of reference voltage levels; an adder for adding the first and second digital signals to produce a third digital signal; and a digital to analog converter for providing an output voltage in response to the third digital signal. The method of producing a flexible reference voltage performed by the circuit is also claimed. The invention can be used with a differential protection circuit to provide a series of trip level ranges, with a series of selectable trip levels in each range. This is accomplished in a high accuracy circuit which is relatively simple to construct, thereby minimizing size and complexity of the current sensor module, in differential protection applications, or the circuitry, if used in a power system controller. Standard digital logic components can be used to perform the necessary range/level decoding.

  19. One directional polarized neutron reflectometry with optimized reference layer method

    SciTech Connect

    Masoudi, S. Farhad; Jahromi, Saeed S.

    2012-09-01

    In the past decade, several neutron reflectometry methods for determining the modulus and phase of the complex reflection coefficient of an unknown multilayer thin film have been worked out among which the method of variation of surroundings and reference layers are of highest interest. These methods were later modified for measurement of the polarization of the reflected beam instead of the measurement of the intensities. In their new architecture, these methods not only suffered from the necessity of change of experimental setup but also another difficulty was added to their experimental implementations. This deficiency was related to the limitations of the technology of the neutron reflectometers that could only measure the polarization of the reflected neutrons in the same direction as the polarization of the incident beam. As the instruments are limited, the theory has to be optimized so that the experiment could be performed. In a recent work, we developed the method of variation of surroundings for one directional polarization analysis. In this new work, the method of reference layer with polarization analysis has been optimized to determine the phase and modulus of the unknown film with measurement of the polarization of the reflected neutrons in the same direction as the polarization of the incident beam.

  20. Recommendations and best practices for reference standards and reagents used in bioanalytical method validation.

    PubMed

    Bower, Joseph F; McClung, Jennifer B; Watson, Carl; Osumi, Takahiko; Pastre, Kátia

    2014-03-01

    The continued globalization of pharmaceutics has increased the demand for companies to know and understand the regulations that exist across the globe. One hurdle facing pharmaceutical and biotechnology companies developing new drug candidates is interpreting the current regulatory guidance documents and industry publications associated with bioanalytical method validation (BMV) from each of the different agencies throughout the world. The objective of this commentary is to provide our opinions on the best practices for reference standards and key reagents, such as metabolites and internal standards used in the support of regulated bioanalysis based on a review of current regulatory guidance documents and industry white papers for BMV.

  1. Methods to estimate irrigated reference crop evapotranspiration - a review.

    PubMed

    Kumar, R; Jat, M K; Shankar, V

    2012-01-01

    Efficient water management of crops requires accurate irrigation scheduling which, in turn, requires the accurate measurement of crop water requirement. Irrigation is applied to replenish depleted moisture for optimum plant growth. Reference evapotranspiration plays an important role for the determination of water requirements for crops and irrigation scheduling. Various models/approaches varying from empirical to physically base distributed are available for the estimation of reference evapotranspiration. Mathematical models are useful tools to estimate the evapotranspiration and water requirement of crops, which is essential information required to design or choose best water management practices. In this paper the most commonly used models/approaches, which are suitable for the estimation of daily water requirement for agricultural crops grown in different agro-climatic regions, are reviewed. Further, an effort has been made to compare the accuracy of various widely used methods under different climatic conditions.

  2. Radiometric reference for weak radiations: comparison of methods

    NASA Astrophysics Data System (ADS)

    Ghazi-Bellouati, A.; Razet, A.; Bastie, J.; Himbert, M. E.; Degiovanni, I. P.; Castelletto, S.; Rastello, M. L.

    2005-08-01

    The parametric down conversion of photons generated in a non-linear crystal gives rise to two correlated photons. When associated with a system of coincidence counting, this phenomenon allows one to measure the quantum efficiencies of detectors working at a normal rate of photon counting, without the need for reference sources or detectors. At the Institut National de Métrologie (INM) (France), this method was implemented with the aim of developing a new standard detector for the absolute measurement of very weak radiation. The validation of this method is presented from an international comparison between the laboratories of the INM (France) and the Istituto Elettrotecnico Nazionale Galileo Ferraris (IENGF) (Italy) and from a comparison of methods at INM using the French national standard detector, the cryogenic radiometer.

  3. Striking against bioterrorism with advanced proteomics and reference methods.

    PubMed

    Armengaud, Jean

    2017-01-01

    The intentional use by terrorists of biological toxins as weapons has been of great concern for many years. Among the numerous toxins produced by plants, animals, algae, fungi, and bacteria, ricin is one of the most scrutinized by the media because it has already been used in biocrimes and acts of bioterrorism. Improving the analytical toolbox of national authorities to monitor these potential bioweapons all at once is of the utmost interest. MS/MS allows their absolute quantitation and exhibits advantageous sensitivity, discriminative power, multiplexing possibilities, and speed. In this issue of Proteomics, Gilquin et al. (Proteomics 2017, 17, 1600357) present a robust multiplex assay to quantify a set of eight toxins in the presence of a complex food matrix. This MS/MS reference method is based on scheduled SRM and high-quality standards consisting of isotopically labeled versions of these toxins. Their results demonstrate robust reliability based on rather loose scheduling of SRM transitions and good sensitivity for the eight toxins, lower than their oral median lethal doses. In the face of an increased threat from terrorism, relevant reference assays based on advanced proteomics and high-quality companion toxin standards are reliable and firm answers.

  4. Quantifying Backscatter Anisotropy Using the Reference Phantom Method.

    PubMed

    Guerrero, Quinton W; Rosado-Mendez, Ivan M; Drehfal, Lindsey C; Feltovich, Helen; Hall, Timothy J

    2017-07-01

    Acoustic properties can be exploited to infer and evaluate tissue microstructure. However, common assumptions are that the medium of interest is homogeneous and isotropic, and that its underlying physical properties cause diffuse scattering. In this paper, we describe how we developed and tested novel parameters designed to address isotropy/anisotropy in backscattered echo signal power in complex biological tissues. Specifically, we explored isotropy/anisotropy in backscattered power in isotropic phantoms (spherical glass beads), an anisotropic phantom (dialysis phantom with rodlike fibers), and an in vivo human tissue with well-described anisotropy (bicep muscle). Our approach uses the reference phantom method to compensate for system transfer and diffraction losses when electronically beamsteering a linear array transducer. We define three parameters to quantify the presence and orientation of anisotropic scatterers, as well as address magnitude of anisotropy. We found that these parameters can detect and sense the degree of anisotropy in backscatter in both phantoms and bicep muscle. Bias of the summary anisotropy parameters, induced through a speed of sound mismatch of sample media and reference phantom, was less than 0.2 dB if the speed of sound was within ±20 m/s of the sample media. In summary, these new parameters may be useful for testing the assumption of isotropy as well as providing more detailed information about the underlying microstructural sources of backscatter in complex biological tissues.

  5. Harmonizing multiple methods for reconstructing historical potential and reference evapotranspiration

    USGS Publications Warehouse

    Belaineh, Getachew; Sumner, David; Carter, Edward; Clapp, David

    2013-01-01

    Potential evapotranspiration (PET) and reference evapotranspiration (RET) data are usually critical components of hydrologic analysis. Many different equations are available to estimate PET and RET. Most of these equations, such as the Priestley-Taylor and Penman- Monteith methods, rely on detailed meteorological data collected at ground-based weather stations. Few weather stations collect enough data to estimate PET or RET using one of the more complex evapotranspiration equations. Currently, satellite data integrated with ground meteorological data are used with one of these evapotranspiration equations to accurately estimate PET and RET. However, earlier than the last few decades, historical reconstructions of PET and RET needed for many hydrologic analyses are limited by the paucity of satellite data and of some types of ground data. Air temperature stands out as the most generally available meteorological ground data type over the last century. Temperature-based approaches used with readily available historical temperature data offer the potential for long period-of-record PET and RET historical reconstructions. A challenge is the inconsistency between the more accurate, but more data intensive, methods appropriate for more recent periods and the less accurate, but less data intensive, methods appropriate to the more distant past. In this study, multiple methods are harmonized in a seamless reconstruction of historical PET and RET by quantifying and eliminating the biases of the simple Hargreaves-Samani method relative to the more complex and accurate Priestley-Taylor and Penman-Monteith methods. This harmonization process is used to generate long-term, internally consistent, spatiotemporal databases of PET and RET.

  6. Marine Biotoxins: Occurrence, Toxicity, Regulatory Limits and Reference Methods

    PubMed Central

    Visciano, Pierina; Schirone, Maria; Berti, Miriam; Milandri, Anna; Tofalo, Rosanna; Suzzi, Giovanna

    2016-01-01

    Harmful algal blooms are natural phenomena caused by the massive growth of phytoplankton that may contain highly toxic chemicals, the so-called marine biotoxins causing illness and even death to both aquatic organisms and humans. Their occurrence has been increased in frequency and severity, suggesting a worldwide public health risk. Marine biotoxins can accumulate in bivalve molluscs and regulatory limits have been set for some classes according to European Union legislation. These compounds can be distinguished in water- and fat-soluble molecules. The first group involves those of Paralytic Shellfish Poisoning and Amnesic Shellfish Poisoning, whereas the toxins soluble in fat can cause Diarrheic Shellfish Poisoning and Neurotoxic Shellfish Poisoning. Due to the lack of long-term toxicity studies, establishing tolerable daily intakes for any of these marine biotoxins was not possible, but an acute reference dose can be considered more appropriate, because these molecules show an acute toxicity. Dietary exposure assessment is linked both to the levels of marine biotoxins present in bivalve molluscs and the portion that could be eaten by consumers. Symptoms may vary from a severe gastrointestinal intoxication with diarrhea, nausea, vomiting, and abdominal cramps to neurological disorders such as ataxia, dizziness, partial paralysis, and respiratory distress. The official method for the detection of marine biotoxins is the mouse bioassay (MBA) showing some limits due to ethical restrictions and insufficient specificity. For this reason, the liquid chromatography–mass spectrometry method has replaced MBA as the reference technique. However, the monitoring of algal blooms producing marine biotoxins should be regularly assessed in order to obtain more reliable, accurate estimates of bloom toxicity and their potential impacts. PMID:27458445

  7. Marine Biotoxins: Occurrence, Toxicity, Regulatory Limits and Reference Methods.

    PubMed

    Visciano, Pierina; Schirone, Maria; Berti, Miriam; Milandri, Anna; Tofalo, Rosanna; Suzzi, Giovanna

    2016-01-01

    Harmful algal blooms are natural phenomena caused by the massive growth of phytoplankton that may contain highly toxic chemicals, the so-called marine biotoxins causing illness and even death to both aquatic organisms and humans. Their occurrence has been increased in frequency and severity, suggesting a worldwide public health risk. Marine biotoxins can accumulate in bivalve molluscs and regulatory limits have been set for some classes according to European Union legislation. These compounds can be distinguished in water- and fat-soluble molecules. The first group involves those of Paralytic Shellfish Poisoning and Amnesic Shellfish Poisoning, whereas the toxins soluble in fat can cause Diarrheic Shellfish Poisoning and Neurotoxic Shellfish Poisoning. Due to the lack of long-term toxicity studies, establishing tolerable daily intakes for any of these marine biotoxins was not possible, but an acute reference dose can be considered more appropriate, because these molecules show an acute toxicity. Dietary exposure assessment is linked both to the levels of marine biotoxins present in bivalve molluscs and the portion that could be eaten by consumers. Symptoms may vary from a severe gastrointestinal intoxication with diarrhea, nausea, vomiting, and abdominal cramps to neurological disorders such as ataxia, dizziness, partial paralysis, and respiratory distress. The official method for the detection of marine biotoxins is the mouse bioassay (MBA) showing some limits due to ethical restrictions and insufficient specificity. For this reason, the liquid chromatography-mass spectrometry method has replaced MBA as the reference technique. However, the monitoring of algal blooms producing marine biotoxins should be regularly assessed in order to obtain more reliable, accurate estimates of bloom toxicity and their potential impacts.

  8. In-house reference material characterization using nuclear methods

    SciTech Connect

    Anderson, D.L.; Cunningham, W.C.

    1994-12-31

    Inclusion of standard reference materials (SRMs) in chemical analysis schemes is an important component of quality control (QC) programs. Effectiveness as QC materials depends on how closely SRM matrices match (in both bulk composition and analyte concentrations) those of the unknowns. For food analysis, wide ranges of matrices and compositions are encountered, and appropriate SRM availability is limited. Moreover, day-to-day use of gram quantities of SRMs during analyses of large numbers of food test samples, such as for the Food and Drug Administration`s (FDA`s) Total Diet Study Program, results in high costs and rapid depletion. To overcome these problems, FDA`s Elemental Research Branch has examined two off-the-shelf foods, soy-based powdered infant formula (SPIF), and cocoa powder, as candidates for in-house (secondary) reference materials. Both materials are relatively homogeneous in particle size and composition and have long shelf lives with no refrigeration. The SPIF is formulated to be a complete infant diet with proper fat content and is fortified with essential vitamins, minerals, and essential elements. At FDA`s Kansas City laboratory, cocoa powder was found to have enough fat to require (desirably) moderate effort for acid digestion and to have cadmium, nickel, and lead concentrations at levels appropriate for graphite furnace atomic absorption spectrometry QC procedures. This material also has suitable concentrations for determination of a number of other elements of interest (e.g., calcium, copper, chromium, iron, potassium, magnesium, manganese, and zinc). Basis weight stabilities, the number of analytes quantitatable by neutron activation methods, and homogeneities for these materials were investigated.

  9. Circuit Riding: A Method for Providing Reference Services.

    ERIC Educational Resources Information Center

    Plunket, Linda; And Others

    1983-01-01

    Discussion of the design and implementation of the Circuit Rider Librarian Program, a shared services project for delivering reference services to eight hospitals in Maine, includes a cost analysis of services and description of user evaluation survey. Five references, composite results of the survey, and postgrant options proposal are appended.…

  10. Rethinking Reference: Consistent Values, New Methods, and Different Tools

    ERIC Educational Resources Information Center

    Kendrick, Kaetrena Davis

    2011-01-01

    The core duties of the reference librarian inherently mandate that the work environment is not unlike a kaleidoscope: Students and faculty revolve within and around the library, and reference and public services workers do the same; every move temporarily redesigning the library, its collections, and even its very role on campus into something…

  11. Rethinking Reference: Consistent Values, New Methods, and Different Tools

    ERIC Educational Resources Information Center

    Kendrick, Kaetrena Davis

    2011-01-01

    The core duties of the reference librarian inherently mandate that the work environment is not unlike a kaleidoscope: Students and faculty revolve within and around the library, and reference and public services workers do the same; every move temporarily redesigning the library, its collections, and even its very role on campus into something…

  12. Circuit Riding: A Method for Providing Reference Services.

    ERIC Educational Resources Information Center

    Plunket, Linda; And Others

    1983-01-01

    Discussion of the design and implementation of the Circuit Rider Librarian Program, a shared services project for delivering reference services to eight hospitals in Maine, includes a cost analysis of services and description of user evaluation survey. Five references, composite results of the survey, and postgrant options proposal are appended.…

  13. LA-ICP-MS of magnetite: Methods and reference materials

    USGS Publications Warehouse

    Nadoll, P.; Koenig, A.E.

    2011-01-01

    Magnetite (Fe3O4) is a common accessory mineral in many geologic settings. Its variable geochemistry makes it a powerful petrogenetic indicator. Electron microprobe (EMPA) analyses are commonly used to examine major and minor element contents in magnetite. Laser ablation ICP-MS (LA-ICP-MS) is applicable to trace element analyses of magnetite but has not been widely employed to examine compositional variations. We tested the applicability of the NIST SRM 610, the USGS GSE-1G, and the NIST SRM 2782 reference materials (RMs) as external standards and developed a reliable method for LA-ICP-MS analysis of magnetite. LA-ICP-MS analyses were carried out on well characterized magnetite samples with a 193 nm, Excimer, ArF LA system. Although matrix-matched RMs are sometimes important for calibration and normalization of LA-ICP-MS data, we demonstrate that glass RMs can produce accurate results for LA-ICP-MS analyses of magnetite. Cross-comparison between the NIST SRM 610 and USGS GSE-1G indicates good agreement for magnetite minor and trace element data calibrated with either of these RMs. Many elements show a sufficiently good match between the LA-ICP-MS and the EMPA data; for example, Ti and V show a close to linear relationship with correlation coefficients, R2 of 0.79 and 0.85 respectively. ?? 2011 The Royal Society of Chemistry.

  14. Pursuit of Licensure by Senior Drivers Referred by Police to a State Licensing Agency's Medical Advisory Board.

    PubMed

    Soderstrom, Carl A; Scottino, Mary Anne; Burch, Cynthia A; Ho, Shiu M; Kerns, Timothy J; Joyce, John J

    2010-01-01

    In all fifty United States and the District of Columbia, police Requests for Re-examination (RRE) concerning fitness to driver are accepted by licensing agencies. This study assessed licensing outcomes of senior drivers, ≥75 years of age, who had RREs submitted to the Medical Advisory Board (MAB) of a Maryland Motor Vehicle Administration from March 2005 through April 2007. RRE traffic event information (including crashed, did not crash), driver demographic information, initial MAB recommendations (suspension vs no suspension), driving occupational therapists assessments, and drivers' pursuit of continued licensure were entered into a database. During the period of study, 475 RREs were referred to the MAB. The percent of referred senior drivers (n=240, 50.4%) was similar to that of younger drivers (n=235, 49.5%). A higher percentage of senior drivers retired from driving compared to younger drivers; being, 57.1% vs 23.8% (p <.01), respectively. Further analyses limited to the 240 senior drivers found: 139 (57.9%) were men, 150 (62.5%) were 75-84 years of age, 119 (49.5%) were noted to be disoriented at the traffic scene, 141 (58.8%) were involved in a crash, and 127 (52.9%) were initially suspended as the result of MAB review. The following factors were significantly related to retiring from driving, initial MAB suspension and greater age. Of the 127 drivers who were initially suspended, 82 (64.6%) retired from driving, and 45 (35.4%) pursued further licensure (p <0.01). In contrast, the percentage of non-suspended drivers who did or did not pursue further licensure was similar; being 48.7% vs 51.3%. Among drivers ≥85 years of age, 68.9% retired from driving, compared with 50% of the drivers who were 75 to 84 years of age (p <0.01) While not statisically significant, higher percentages of driving retirement were noted for the following: sex - a greater percentage of men compared to women (61.9% vs 49.5%); confusion at the traffic scene (confused, 57.1% vs non

  15. Parametric methods for estimating covariate-dependent reference limits.

    PubMed

    Virtanen, Arja; Kairisto, Veli; Uusipaikka, Esa

    2004-01-01

    Age-specific reference limits are required for many clinical laboratory measurements. Statistical assessment of calculated intervals must be performed to obtain reliable reference limits. When parametric, covariate-dependent limits are derived, normal distribution theory usually is applied due to its mathematical simplicity and relative ease of fitting. However, it is not always possible to transform data and achieve a normal distribution. Therefore, models other than those based on normal distribution theory are needed. Generalized linear model theory offers one such alternative. Regardless of the statistical model used, the assumptions behind the model should always be examined.

  16. The method for the modern selenographic reference systems analysis

    NASA Astrophysics Data System (ADS)

    Andreev, Alexey; Nefedev, Yuri; Demina, Natalia; Demin, Sergey; Petrova, Natalia

    2016-10-01

    In this work analysis of the reference systems of modern selenographic systems was made. The center of the Moon's mass position relative to its center of figure was determined from the data of "Clementine" and "Kaguya" missions and "ULCN" and "KSC-1162" catalogues. The knowledge of the Moon's center of mass position relative to its center of figure is important for researches of the lunar origin, structure and evolution and in terms of precision solutions circumlunar navigation tasks. At the present this task is the most relevant and demanded for cosmic lunar missions.The expansions by spherical harmonics N=5 degree and order of the lunar function h (selenographic longitude, selenographic latitude) using the package ASNI were executed. Module of the expansion of the local area to surfaces to full sphere was used. The parameters of cosmic missions are given for comparison (SAI; Bills, Ferrari).As a model describing the behavior of the relief on the lunar sphere is used the expansion of the height in a series of spherical harmonics (Sagitov, 1979) in the form of a regression model (Valeev, 2001). To obtain the expansions in spherical harmonics in order to create a digital model and determine estimations of the center of mass position of the Moon relative to its center of the figure required in the future was usedsoftware package ASSR "Sphere" (an automated system of scientific research).ASSR "Sphere" is intended to describe the distribution of various values of the parameters (topography, gravity, magnetic, and other types of potential fields) on the sphere and its parts which were measured in points with known coordinates. Using this bundled software one can generate models of the specificform,carry out forecasting in the form of cross-sections, contour, tone and three-dimensional representation of the distribution of characteristicsvalues. The formation of models is accompanied by estimation of their quality and diagnostic of adherence of least square method

  17. The Organic Food Method and Movement: An Interdisciplinary Reference Review

    ERIC Educational Resources Information Center

    Park, Elizabeth E.

    2011-01-01

    From popular movies to New York Times bestsellers, organic food is widely acknowledged to be of growing importance. Many community college students are asking: How is organic food different from everything else in the grocery store? What impact does farming have on the environment? How safe is our food? A survey of reference works introduces…

  18. The Organic Food Method and Movement: An Interdisciplinary Reference Review

    ERIC Educational Resources Information Center

    Park, Elizabeth E.

    2011-01-01

    From popular movies to New York Times bestsellers, organic food is widely acknowledged to be of growing importance. Many community college students are asking: How is organic food different from everything else in the grocery store? What impact does farming have on the environment? How safe is our food? A survey of reference works introduces…

  19. Web of science: a unique method of cited reference searching.

    PubMed Central

    Sevinc, Alper

    2004-01-01

    The number of times an article is acknowledged as a reference in another article reflects its scientific impact. Citation analysis is one of the parameters for assessing the quality of research published in scientific, technology and social science journals. Web of Science enables users to search current and retrospective multidisciplinary information. Parameters and practical applications evaluating journal and article citation characteristics available through the Science Citation Index are summarized. Images Figure 1 Figure 2 PMID:15253331

  20. Web of science: a unique method of cited reference searching.

    PubMed

    Sevinc, Alper

    2004-07-01

    The number of times an article is acknowledged as a reference in another article reflects its scientific impact. Citation analysis is one of the parameters for assessing the quality of research published in scientific, technology and social science journals. Web of Science enables users to search current and retrospective multidisciplinary information. Parameters and practical applications evaluating journal and article citation characteristics available through the Science Citation Index are summarized.

  1. Reference-based source separation method for identification of brain regions involved in a reference state from intracerebral EEG

    PubMed Central

    Samadi, Samareh; Amini, Ladan; Cosandier-Rimélé, Delphine; Soltanian-Zadeh, Hamid; Jutten, Christian

    2013-01-01

    In this paper, we present a fast method to extract the sources related to interictal epileptiform state. The method is based on general eigenvalue decomposition using two correlation matrices during: 1) periods including interictal epileptiform discharges (IED) as a reference activation model and 2) periods excluding IEDs or abnormal physiological signals as background activity. After extracting the most similar sources to the reference or IED state, IED regions are estimated by using multiobjective optimization. The method is evaluated using both realistic simulated data and actual intracerebral electroencephalography recordings of patients suffering from focal epilepsy. These patients are seizure-free after the resective surgery. Quantitative comparisons of the proposed IED regions with the visually inspected ictal onset zones by the epileptologist and another method of identification of IED regions reveal good performance. PMID:23428609

  2. Reference-based source separation method for identification of brain regions involved in a reference state from intracerebral EEG.

    PubMed

    Samadi, Samareh; Amini, Ladan; Cosandier-Rimélé, Delphine; Soltanian-Zadeh, Hamid; Jutten, Christian

    2013-07-01

    In this paper, we present a fast method to extract the sources related to interictal epileptiform state. The method is based on general eigenvalue decomposition using two correlation matrices during: 1) periods including interictal epileptiform discharges (IED) as a reference activation model and 2) periods excluding IEDs or abnormal physiological signals as background activity. After extracting the most similar sources to the reference or IED state, IED regions are estimated by using multiobjective optimization. The method is evaluated using both realistic simulated data and actual intracerebral electroencephalography recordings of patients suffering from focal epilepsy. These patients are seizure-free after the resective surgery. Quantitative comparisons of the proposed IED regions with the visually inspected ictal onset zones by the epileptologist and another method of identification of IED regions reveal good performance.

  3. GTX Reference Vehicle Structural Verification Methods and Weight Summary

    NASA Technical Reports Server (NTRS)

    Hunter, J. E.; McCurdy, D. R.; Dunn, P. W.

    2002-01-01

    The design of a single-stage-to-orbit air breathing propulsion system requires the simultaneous development of a reference launch vehicle in order to achieve the optimal mission performance. Accordingly, for the GTX study a 300-lb payload reference vehicle was preliminarily sized to a gross liftoff weight (GLOW) of 238,000 lb. A finite element model of the integrated vehicle/propulsion system was subjected to the trajectory environment and subsequently optimized for structural efficiency. This study involved the development of aerodynamic loads mapped to finite element models of the integrated system in order to assess vehicle margins of safety. Commercially available analysis codes were used in the process along with some internally developed spreadsheets and FORTRAN codes specific to the GTX geometry for mapping of thermal and pressure loads. A mass fraction of 0.20 for the integrated system dry weight has been the driver for a vehicle design consisting of state-of-the-art composite materials in order to meet the rigid weight requirements. This paper summarizes the methodology used for preliminary analyses and presents the current status of the weight optimization for the structural components of the integrated system.

  4. GTX Reference Vehicle Structural Verification Methods and Weight Summary

    NASA Technical Reports Server (NTRS)

    Hunter, J. E.; McCurdy, D. R.; Dunn, P. W.

    2002-01-01

    The design of a single-stage-to-orbit air breathing propulsion system requires the simultaneous development of a reference launch vehicle in order to achieve the optimal mission performance. Accordingly, for the GTX study a 300-lb payload reference vehicle was preliminary sized to a gross liftoff weight (GLOW) of 238,000 lb. A finite element model of the integrated vehicle/propulsion system was subjected to the trajectory environment and subsequently optimized for structural efficiency. This study involved the development of aerodynamic loads mapped to finite element models of the integrated system in order to assess vehicle margins of safety. Commercially available analysis codes were used in the process along with some internally developed spread-sheets and FORTRAN codes specific to the GTX geometry for mapping of thermal and pressure loads. A mass fraction of 0.20 for the integrated system dry weight has been the driver for a vehicle design consisting of state-of-the-art composite materials in order to meet the rigid weight requirements. This paper summarizes the methodology used for preliminary analyses and presents the current status of the weight optimization for the structural components of the integrated system.

  5. EVALUATION OF A CRYPTOSPORIDIUM INTERNAL STANDARD FOR DETERMINING RECOVERY WITH ENVIRONMENTAL PROTECTION AGENCY METHOD 1623

    EPA Science Inventory

    The current benchmark method for detecting Cryptosporidium oocysts in water is the U.S. Environmental Protection Agency (U.S. EPA) Method 1623. Studies evaluating this method report that recoveries are highly variable and dependent upon laboratory, water sample, and analyst. Ther...

  6. Aluminum analysis in biological reference material by nondestructive methods

    SciTech Connect

    Landsberger, S.; Arendt, A.; Keck, B.; Glascock, M.

    1988-01-01

    In recent years, the determination of aluminum in biological materials has become the subject of many research projects. This interest stems from an increasing knowledge of the toxicity of aluminum to both aquatic and human life. Unfortunately, the detection of aluminum in biological materials has proven troublesome. The use of traditional chemical determinations has been shown to be very long and somewhat complicated. Several attempts have been made using neutron activation analysis, but an interfering reaction must be taken into account. In this experiment the rabbit irradiation facilities at the University of Missouri Research Reactor were used. The aluminum concentrations for eight certified reference materials are shown. When US National Bureau of Standards (NBS) value is given as certified or as an information value, results agree very well. The results for NBS 1572 citrus leaves agree, and NBS 1577 results agree very well with that of Glascock et al.

  7. 40 CFR 75.22 - Reference test methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... molecular weight O2 and CO2 concentrations in the emissions. (4) Method 4 (either the standard procedure... moisture monitoring systems are conducted. For the purpose of determining the stack gas molecular weight... Using Carbon Sorbent Traps”. (iv) When Method 29 in appendix A-8 to part 60 of this chapter or...

  8. 40 CFR 60.396 - Reference methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... methods in appendix A to this part, except as provided in § 60.8 shall be used to conduct performance...) For Method 25, the sampling time for each of three runs must be at least one hour. The minimum sample volume must be 0.003 dscm except that shorter sampling times or smaller volumes, when necessitated by...

  9. [Methods of contraception, with special reference to sterilization].

    PubMed

    Lampé, L

    1980-09-28

    Broader use of sterilization as a method of family planning and population control is favored. The author points out all the dangers and side effects associated with various methods of contraception, i.e., the higher death and damage rate with increasing age, and smoking. Even with the IUD the death rate is low but not negligible; 3-4% have complications, while 0.4% require surgery (laparotomy, removal of uterus, removal of uterine appendix). For women over 35 or for mothers with 2-3 children, sterilization is the best method of contraception.

  10. A global multicenter study on reference values: 1. Assessment of methods for derivation and comparison of reference intervals.

    PubMed

    Ichihara, Kiyoshi; Ozarda, Yesim; Barth, Julian H; Klee, George; Qiu, Ling; Erasmus, Rajiv; Borai, Anwar; Evgina, Svetlana; Ashavaid, Tester; Khan, Dilshad; Schreier, Laura; Rolle, Reynan; Shimizu, Yoshihisa; Kimura, Shogo; Kawano, Reo; Armbruster, David; Mori, Kazuo; Yadav, Binod K

    2017-04-01

    The IFCC Committee on Reference Intervals and Decision Limits coordinated a global multicenter study on reference values (RVs) to explore rational and harmonizable procedures for derivation of reference intervals (RIs) and investigate the feasibility of sharing RIs through evaluation of sources of variation of RVs on a global scale. For the common protocol, rather lenient criteria for reference individuals were adopted to facilitate harmonized recruitment with planned use of the latent abnormal values exclusion (LAVE) method. As of July 2015, 12 countries had completed their study with total recruitment of 13,386 healthy adults. 25 analytes were measured chemically and 25 immunologically. A serum panel with assigned values was measured by all laboratories. RIs were derived by parametric and nonparametric methods. The effect of LAVE methods is prominent in analytes which reflect nutritional status, inflammation and muscular exertion, indicating that inappropriate results are frequent in any country. The validity of the parametric method was confirmed by the presence of analyte-specific distribution patterns and successful Gaussian transformation using the modified Box-Cox formula in all countries. After successful alignment of RVs based on the panel test results, nearly half the analytes showed variable degrees of between-country differences. This finding, however, requires confirmation after adjusting for BMI and other sources of variation. The results are reported in the second part of this paper. The collaborative study enabled us to evaluate rational methods for deriving RIs and comparing the RVs based on real-world datasets obtained in a harmonized manner. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Mekong Regional Land Cover Monitoring System Reference Methods

    NASA Astrophysics Data System (ADS)

    Saah, D.; Aekakkararungroj, A.; Phongsapan, K.; Towashiraporn, P.; Triepke, J.; Maus, P.; Tenneson, K.; Anderson, E.; Cutter, P. G.; Ganz, D.; Ate, P.; Markert, K. N.

    2016-12-01

    In 2015, SERVIR-Mekong conducted a geospatial needs assessment for the Lower Mekong countries which included individual country consultations. The assessment revealed that many countries were dependent on land cover and land use maps for land resource planning, quantifying ecosystem services including resilience to climate change, biodiversity conservation, and other critical social issues. Many of the Lower Mekong countries have developed national scale land cover maps derived in part from remote sensing products and geospatial technologies. However, updates are infrequent and classification systems and accuracy assessment do not always meet the needs of key user groups. In addition, data products stop at political boundaries and are often not accessible. Many of the Lower Mekong countries rely on global land cover products to fill the gaps of their national efforts, compromising consistency between data and policies. These gaps in national efforts can be filled by a flexible regional land cover monitoring system that is co-developed by regional partners with the specific intention of meeting national transboundary needs, for example including consistent forest definitions in transboundary watersheds. During this assessment, regional stakeholders identified a need for a land cover monitoring system that will produce frequent, high quality land cover maps using a consistent regional classification scheme that is compatible with national country needs. This system is dependent on a sustainable source of field data that insures data quality and improves potential impact. Based on this need a collaborative workshop was held to create a robust regional reference data system that integrates results from field data, national inventories and high resolution imagery. The results presented here highlights the value of collaboratively developed systems that use data convergence to improve land cover mapping results for multiple end users.

  12. 40 CFR 75.22 - Reference test methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... continuous moisture monitoring systems are conducted. For the purpose of determining the stack gas molecular weight, however, the alternative wet bulb-dry bulb technique for approximating the stack gas moisture... this chapter: (i) Section 7.1 of the method allowing for use of prepared calibration gas mixtures that...

  13. 40 CFR 75.22 - Reference test methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... continuous moisture monitoring systems are conducted. For the purpose of determining the stack gas molecular weight, however, the alternative wet bulb-dry bulb technique for approximating the stack gas moisture... this chapter: (i) Section 7.1 of the method allowing for use of prepared calibration gas mixtures that...

  14. 40 CFR 75.22 - Reference test methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... continuous moisture monitoring systems are conducted. For the purpose of determining the stack gas molecular weight, however, the alternative wet bulb-dry bulb technique for approximating the stack gas moisture... this chapter: (i) Section 7.1 of the method allowing for use of prepared calibration gas mixtures that...

  15. Three methods of interfacing with the private sector by mental health agencies.

    PubMed

    McRae, J A

    1989-01-01

    This article outlines three methods of mental health marketing--formal, intermediary, and interactive. It discusses advantages and disadvantages of each method. These approaches are particularly good for public, non-profit agencies and individuals in contacting the private sector. The need for flexibility and marketing mix is emphasized.

  16. 7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. 801.7 Section 801.7 Agriculture Regulations of the Department of Agriculture... methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. (a) Reference methods. (1)...

  17. 7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. 801.7 Section 801.7 Agriculture Regulations of the Department of Agriculture... methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. (a) Reference methods. (1)...

  18. 7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. 801.7 Section 801.7 Agriculture Regulations of the Department of Agriculture... methods and tolerances for near-infrared spectroscopy (NIRS) analyzers. (a) Reference methods. (1)...

  19. Mental Health Worker Training. A State-of-the-Art Reference on Statewide Mental Health Agency Training Programs.

    ERIC Educational Resources Information Center

    Southern Regional Education Board, Atlanta, GA.

    A study examined the statewide mental health agency training programs for paraprofessional mental health workers that exist throughout the United States. During the study, researchers contacted all 50 state mental health manpower development offices and requested copies of statewide training programs, instructional materials, training needs…

  20. Design of zero reference codes by means of a global optimization method.

    PubMed

    Saez-Landete, José; Alonso, José; Bernabeu, Eusebio

    2005-01-10

    The grating measurement systems can be used for displacement and angle measurements. They require of zero reference codes to obtain zero reference signals and absolute measures. The zero reference signals are obtained from the autocorrelation of two identical zero reference codes. The design of codes which generate optimum signals is rather complex, especially for larges codes. In this paper we present a global optimization method, a DIRECT algorithm for the design of zero reference codes. This method proves to be a powerful tool for solving this inverse problem.

  1. Design of zero reference codes by means of a global optimization method

    NASA Astrophysics Data System (ADS)

    Saez Landete, José; Alonso, José; Bernabeu, Eusebio

    2005-01-01

    The grating measurement systems can be used for displacement and angle measurements. They require of zero reference codes to obtain zero reference signals and absolute measures. The zero reference signals are obtained from the autocorrelation of two identical zero reference codes. The design of codes which generate optimum signals is rather complex, especially for larges codes. In this paper we present a global optimization method, a DIRECT algorithm for the design of zero reference codes. This method proves to be a powerful tool for solving this inverse problem.

  2. 77 FR 55832 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of a New Equivalent Method

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-11

    ... monitoring ambient air quality. SUMMARY: Notice is hereby given that the Environmental Protection Agency (EPA... monitoring agencies under the requirements of 40 CFR part 58, Ambient Air Quality Surveillance. For such..., Ambient Air Quality Monitoring Program'' EPA-454/B-08-003, December, 2008. Provisions...

  3. Evaluation of Gas-filled Ionization Chamber Method for Radon Measurement at Two Reference Facilities

    SciTech Connect

    Ishikawa, Tetsuo; Tokonami, Shinji; Kobayashi, Yosuke; Sorimachi, Atsuyuki; Yatabe, Yoshinori; Miyahara, Nobuyuki

    2008-08-07

    For quality assurance, gas-filled ionization chamber method was tested at two reference facilities for radon calibration: EML (USA) and PTB (Germany). Consequently, the radon concentrations estimated by the ionization chamber method were in good agreement with the reference radon concentrations provided by EML as well as PTB.

  4. 40 CFR 53.14 - Modification of a reference or equivalent method.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... as a reference or equivalent method shall report to the EPA Administrator prior to implementation any intended modification of the method, including but not limited to modifications of design or...

  5. 40 CFR 53.14 - Modification of a reference or equivalent method.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... as a reference or equivalent method shall report to the EPA Administrator prior to implementation any intended modification of the method, including but not limited to modifications of design or...

  6. SYSTEMATIC ERROR REDUCTION: NON-TILTED REFERENCE BEAM METHOD FOR LONG TRACE PROFILER.

    SciTech Connect

    QIAN,S.; QIAN, K.; HONG, Y.; SENG, L.; HO, T.; TAKACS, P.

    2007-08-25

    Systematic error in the Long Trace Profiler (LTP) has become the major error source as measurement accuracy enters the nanoradian and nanometer regime. Great efforts have been made to reduce the systematic error at a number of synchrotron radiation laboratories around the world. Generally, the LTP reference beam has to be tilted away from the optical axis in order to avoid fringe overlap between the sample and reference beams. However, a tilted reference beam will result in considerable systematic error due to optical system imperfections, which is difficult to correct. Six methods of implementing a non-tilted reference beam in the LTP are introduced: (1) application of an external precision angle device to measure and remove slide pitch error without a reference beam, (2) independent slide pitch test by use of not tilted reference beam, (3) non-tilted reference test combined with tilted sample, (4) penta-prism scanning mode without a reference beam correction, (5) non-tilted reference using a second optical head, and (6) alternate switching of data acquisition between the sample and reference beams. With a non-tilted reference method, the measurement accuracy can be improved significantly. Some measurement results are presented. Systematic error in the sample beam arm is not addressed in this paper and should be treated separately.

  7. Investigation of the Preservation Method within Environmental Protection Agency Method 200.8

    EPA Science Inventory

    Lead (Pb) is a trace metal that is closely regulated in drinking water systems because of its harmful toxicity. The U.S. Environmental Protection Agency (USEPA) issued the Lead and Copper Rule (LCR), which defines the action level for Lead as 0.015 mg/L. Researchers and drinking ...

  8. Investigation of the Preservation Method within Environmental Protection Agency Method 200.8

    EPA Science Inventory

    Lead (Pb) is a trace metal that is closely regulated in drinking water systems because of its harmful toxicity. The U.S. Environmental Protection Agency (USEPA) issued the Lead and Copper Rule (LCR), which defines the action level for Lead as 0.015 mg/L. Researchers and drinking ...

  9. Kjeldahl nitrogen analysis as a reference method for protein determination in dairy products.

    PubMed

    Lynch, J M; Barbano, D M

    1999-01-01

    Measurement of total nitrogen by Kjeldahl analysis is the historical reference method for determination of the protein content of dairy products and is used for both calibration and validation of alternative methods for protein determination. Accurate evaluation of alternative methods is not possible if there is large uncertainty regarding the reference values. When Kjeldahl analysis is used to establish reference values, the performance of the Kjeldahl testing must be verified and within established expectations. Advice is given for Kjeldahl system optimization, evaluation of test results, and trouble-shooting. Techniques for successful Kjeldahl nitrogen analysis of dairy products other than milk are discussed.

  10. Resampling methods in Microsoft Excel® for estimating reference intervals.

    PubMed

    Theodorsson, Elvar

    2015-01-01

    Computer-intensive resampling/bootstrap methods are feasible when calculating reference intervals from non-Gaussian or small reference samples. Microsoft Excel® in version 2010 or later includes natural functions, which lend themselves well to this purpose including recommended interpolation procedures for estimating 2.5 and 97.5 percentiles. 
The purpose of this paper is to introduce the reader to resampling estimation techniques in general and in using Microsoft Excel® 2010 for the purpose of estimating reference intervals in particular.
 Parametric methods are preferable to resampling methods when the distributions of observations in the reference samples is Gaussian or can transformed to that distribution even when the number of reference samples is less than 120. Resampling methods are appropriate when the distribution of data from the reference samples is non-Gaussian and in case the number of reference individuals and corresponding samples are in the order of 40. At least 500-1000 random samples with replacement should be taken from the results of measurement of the reference samples.

  11. Resampling methods in Microsoft Excel® for estimating reference intervals

    PubMed Central

    Theodorsson, Elvar

    2015-01-01

    Computer- intensive resampling/bootstrap methods are feasible when calculating reference intervals from non-Gaussian or small reference samples. Microsoft Excel® in version 2010 or later includes natural functions, which lend themselves well to this purpose including recommended interpolation procedures for estimating 2.5 and 97.5 percentiles.
The purpose of this paper is to introduce the reader to resampling estimation techniques in general and in using Microsoft Excel® 2010 for the purpose of estimating reference intervals in particular.
Parametric methods are preferable to resampling methods when the distributions of observations in the reference samples is Gaussian or can transformed to that distribution even when the number of reference samples is less than 120. Resampling methods are appropriate when the distribution of data from the reference samples is non-Gaussian and in case the number of reference individuals and corresponding samples are in the order of 40. At least 500-1000 random samples with replacement should be taken from the results of measurement of the reference samples. PMID:26527366

  12. 40 CFR 53.4 - Applications for reference or equivalent method determinations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 6 2013-07-01 2013-07-01 false Applications for reference or... Provisions § 53.4 Applications for reference or equivalent method determinations. (a) Applications for FRM or... Carolina 27703). (b) Each application shall be signed by an authorized representative of the applicant...

  13. Improving Reference Service: The Case for Using a Continuous Quality Improvement Method.

    ERIC Educational Resources Information Center

    Aluri, Rao

    1993-01-01

    Discusses the evaluation of library reference service; examines problems with past evaluations, including the lack of long-term planning and a systems perspective; and suggests a method for continuously monitoring and improving reference service using quality improvement tools such as checklists, cause and effect diagrams, Pareto charts, and…

  14. [Quality evaluation of guizhi fuling capsule using self-control method of reference Chinese medicine preparation].

    PubMed

    Geng, Ting; Zhang, Zai-juan; Li, Yan-jing; Ding, Gang; Bi, Yu-an; Wang, Zhen-zhong; Xiao, Wei

    2014-11-01

    Taking guizhi fuling capsule (GZFL) for instance, a new method about reference Chinese medicine preparation which was used as standard substance for the quality evaluation of complex Chinese medicine preparation by the fingerprint of reference preparation instead of standard fingerprint was proposed. It could eliminate the errors from different instruments, chromatographic columns and solve the problem of similarity matching in the absence of standard fingerprint. The qualification of reference GZFL was evaluated according to the quality control method of GZFL from Chinese Pharmacopoeia. Then multiple batches of GZFL were estimated, taking fingerprint of reference preparation and standard fingerprint as references, respectively, at different instruments and chromatographic columns. Finally, the packaging and expiration date for reference GZFL were confirmed according to the results of stability investigation. The results indicated that the fingerprint of reference GZFL could be used to assess the quality of GZFL better than standard fingerprint. The data of accelerated stability and long-term stability test demonstrated that reference GZFL was stable in the conditions of double blister package. Therefore, reference GZFL can be used as standard substance in quality control of GZFL.

  15. Selection of reference standard during method development using the analytical hierarchy process.

    PubMed

    Sun, Wan-yang; Tong, Ling; Li, Dong-xiang; Huang, Jing-yi; Zhou, Shui-ping; Sun, Henry; Bi, Kai-shun

    2015-03-25

    Reference standard is critical for ensuring reliable and accurate method performance. One important issue is how to select the ideal one from the alternatives. Unlike the optimization of parameters, the criteria of the reference standard are always immeasurable. The aim of this paper is to recommend a quantitative approach for the selection of reference standard during method development based on the analytical hierarchy process (AHP) as a decision-making tool. Six alternative single reference standards were assessed in quantitative analysis of six phenolic acids from Salvia Miltiorrhiza and its preparations by using ultra-performance liquid chromatography. The AHP model simultaneously considered six criteria related to reference standard characteristics and method performance, containing feasibility to obtain, abundance in samples, chemical stability, accuracy, precision and robustness. The priority of each alternative was calculated using standard AHP analysis method. The results showed that protocatechuic aldehyde is the ideal reference standard, and rosmarinic acid is about 79.8% ability as the second choice. The determination results successfully verified the evaluation ability of this model. The AHP allowed us comprehensive considering the benefits and risks of the alternatives. It was an effective and practical tool for optimization of reference standards during method development. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. [Determination of five components in Pueraria labta decoction with reference extraction method].

    PubMed

    Xue, Cuijuan; Zhang, Jun; Jing, Wenguang; Wang, Yuesheng; Si, Nan; Liu, An

    2012-08-01

    To establish the reference extraction method for determining five components contained in Pueraria labta decoction and detecting the applicability and feasibility of the application of reference extracts according to the quality standard of traditional Chinese medicine. Zorbax C18 chromatographic column (4.6 mm x 250 mm, 5 microm) was used, with methanol-0.02% phosphoric acid (25:75) as the mobile phase and the detection wavelength was set at 250 nm. Self-prepared reference extracts of P. labta was used for determining the content of 3'-hydroxy puerarin, puerarin, 3'-methoxy puerarin, isoflavoues aglycone-8-C-apiose-(1--> 6) glucoside and daidzin and compare with the experimental results obtained with the single reference substance determination method. The reference extraction determination method showed high precision, stability and reproducibility, with coincident determination results with the results obtained with the single reference substance determination method. The reference extraction determination method of P. labta can be used for quality control of P. labta herbs. The study preliminarily proves the feasibility of the application of P. labta in traditional Chinese medicine.

  17. A review on self-reference wavefront methods in optical testing

    NASA Astrophysics Data System (ADS)

    Cornejo-Rodríguez, Alejandro; Granados-Agustín, Fermín. S.

    2013-11-01

    For the testing of components and optical systems, there are diverse methods with different characteristics each one; in the presentation will be done a review of some of them, that can be classified as optical testing techniques, using a self-reference wavefront. Some examples are the lateral shearing interferometers (Bates, Ronchi, Murty), point diffraction interferometer (Linnik), Burch's scattering interferometer, and the knife edge interferometer. Some advantages of such self-reference methods is the fact that are not necessary optical reference surfaces; and usually the light interfering beams have common paths, that implies that the set up is not affected by environment vibrations and other effects.

  18. Model reference adaptive control in fractional order systems using discrete-time approximation methods

    NASA Astrophysics Data System (ADS)

    Abedini, Mohammad; Nojoumian, Mohammad Ali; Salarieh, Hassan; Meghdari, Ali

    2015-08-01

    In this paper, model reference control of a fractional order system has been discussed. In order to control the fractional order plant, discrete-time approximation methods have been applied. Plant and reference model are discretized by Grünwald-Letnikov definition of the fractional order derivative using "Short Memory Principle". Unknown parameters of the fractional order system are appeared in the discrete time approximate model as combinations of parameters of the main system. The discrete time MRAC via RLS identification is modified to estimate the parameters and control the fractional order plant. Numerical results show the effectiveness of the proposed method of model reference adaptive control.

  19. Evaluation of reference crop evapotranspiration methods in arid, semi-arid and humid regions

    USDA-ARS?s Scientific Manuscript database

    It is necessary to find a simpler method in different climatic regions to calculate reference crop evapotranspiration (ETo) since the application of the FAO-56 Penman-Monteith method is often restricted due to unavailability of a full weather data set. Seven ETo methods, the de facto standard FAO-56...

  20. Evaluation of reference evapotranspiration methods in arid, semiarid, and humid regions

    Treesearch

    Fei Gao; Gary Feng; Ying Ouyang; Huixiao Wang; Daniel Fisher; Ardeshir Adeli; Johnie Jenkins

    2017-01-01

    It is often necessary to find a simpler method in different climatic regions to calculate reference crop evapotranspiration (ETo) since the application of the FAO-56 Penman-Monteith method is often restricted due to the unavailability of a comprehensive weather dataset. Seven ETo methods, namely the standard FAO-56 Penman-Monteith, the FAO-24 Radiation, FAO-24 Blaney...

  1. Validation studies of Karl Fisher reference method for moisture in cotton

    USDA-ARS?s Scientific Manuscript database

    With current international standard oven drying (SOD) techniques lacking precision and accuracy statements, a new standard reference method is needed. Volumetric Karl Fischer Titration (KFT) is a widely used measure of moisture content. The method is used in many ASTM methods, 14 NIST SRMs, and te...

  2. Quantification of brain mu-opioid receptors with [11C]carfentanil: reference-tissue methods.

    PubMed

    Endres, Christopher J; Bencherif, Badreddine; Hilton, John; Madar, Igal; Frost, J James

    2003-02-01

    [(11)C]Carfentanil (CFN) is a mu-opioid agonist used for in vivo positron emission tomography (PET) studies of mu-opioid receptors. Previously, a tissue-ratio method was validated for the quantification of CFN binding. However, since that initial validation, several other blood independent (reference-tissue) methods have become available. To evaluate these methods, CFN PET studies with arterial blood sampling were acquired in six healthy male control subjects. Specific binding estimates obtained from reference-tissue methods were compared to those obtained with a more rigorous blood input modeling technique. It was determined that both a graphical method, and a simplified reference tissue model, were more accurate than the tissue-ratio method for quantification of CFN binding.

  3. Adaptive optimization of reference intensity for optical coherence imaging using galvanometric mirror tilting method

    NASA Astrophysics Data System (ADS)

    Kim, Ji-hyun; Han, Jae-Ho; Jeong, Jichai

    2015-09-01

    Integration time and reference intensity are important factors for achieving high signal-to-noise ratio (SNR) and sensitivity in optical coherence tomography (OCT). In this context, we present an adaptive optimization method of reference intensity for OCT setup. The reference intensity is automatically controlled by tilting a beam position using a Galvanometric scanning mirror system. Before sample scanning, the OCT system acquires two dimensional intensity map with normalized intensity and variables in color spaces using false-color mapping. Then, the system increases or decreases reference intensity following the map data for optimization with a given algorithm. In our experiments, the proposed method successfully corrected the reference intensity with maintaining spectral shape, enabled to change integration time without manual calibration of the reference intensity, and prevented image degradation due to over-saturation and insufficient reference intensity. Also, SNR and sensitivity could be improved by increasing integration time with automatic adjustment of the reference intensity. We believe that our findings can significantly aid in the optimization of SNR and sensitivity for optical coherence tomography systems.

  4. Map correlation method: Selection of a reference streamgage to estimate daily streamflow at ungaged catchments.

    USGS Publications Warehouse

    Archfield, Stacey A.; Vogel, Richard M.

    2010-01-01

    Daily streamflow time series are critical to a very broad range of hydrologic problems. Whereas daily streamflow time series are readily obtained from gaged catchments, streamflow information is commonly needed at catchments for which no measured streamflow information exists. At ungaged catchments, methods to estimate daily streamflow time series typically require the use of a reference streamgage, which transfers properties of the streamflow time series at a reference streamgage to the ungaged catchment. Therefore, the selection of a reference streamgage is one of the central challenges associated with estimation of daily streamflow at ungaged basins. The reference streamgage is typically selected by choosing the nearest streamgage; however, this paper shows that selection of the nearest streamgage does not provide a consistent selection criterion. We introduce a new method, termed the map-correlation method, which selects the reference streamgage whose daily streamflows are most correlated with an ungaged catchment. When applied to the estimation of daily streamflow at 28 streamgages across southern New England, daily streamflows estimated by a reference streamgage selected using the map-correlation method generally provides improved estimates of daily streamflow time series over streamflows estimated by the selection and use of the nearest streamgage. The map correlation method could have potential for many other applications including identifying redundancy and uniqueness in a streamgage network, calibration of rainfall runoff models at ungaged sites, as well as for use in catchment classification.

  5. A self-reference PRF-shift MR thermometry method utilizing the phase gradient.

    PubMed

    Langley, Jason; Potter, William; Phipps, Corey; Huang, Feng; Zhao, Qun

    2011-12-21

    In magnetic resonance (MR) imaging, the most widely used and accurate method for measuring temperature is based on the shift in proton resonance frequency (PRF). However, inter-scan motion and bulk magnetic field shifts can lead to inaccurate temperature measurements in the PRF-shift MR thermometry method. The self-reference PRF-shift MR thermometry method was introduced to overcome such problems by deriving a reference image from the heated or treated image, and approximates the reference phase map with low-order polynomial functions. In this note, a new approach is presented to calculate the baseline phase map in self-reference PRF-shift MR thermometry. The proposed method utilizes the phase gradient to remove the phase unwrapping step inherent to other self-reference PRF-shift MR thermometry methods. The performance of the proposed method was evaluated using numerical simulations with temperature distributions following a two-dimensional Gaussian function as well as phantom and in vivo experimental data sets. The results from both the numerical simulations and experimental data show that the proposed method is a promising technique for measuring temperature.

  6. Different equation-of-motion coupled cluster methods with different reference functions: The formyl radical

    NASA Astrophysics Data System (ADS)

    Kuś, Tomasz; Bartlett, Rodney J.

    2008-09-01

    The doublet and quartet excited states of the formyl radical have been studied by the equation-of-motion (EOM) coupled cluster (CC) method. The Sz spin-conserving singles and doubles (EOM-EE-CCSD) and singles, doubles, and triples (EOM-EE-CCSDT) approaches, as well as the spin-flipped singles and doubles (EOM-SF-CCSD) method have been applied, subject to unrestricted Hartree-Fock (HF), restricted open-shell HF, and quasirestricted HF references. The structural parameters, vertical and adiabatic excitation energies, and harmonic vibrational frequencies have been calculated. The issue of the reference function choice for the spin-flipped (SF) method and its impact on the results has been discussed using the experimental data and theoretical results available. The results show that if the appropriate reference function is chosen so that target states differ from the reference by only single excitations, then EOM-EE-CCSD and EOM-SF-CCSD methods give a very good description of the excited states. For the states that have a non-negligible contribution of the doubly excited configurations one is able to use the SF method with such a reference function, that in most cases the performance of the EOM-SF-CCSD method is better than that of the EOM-EE-CCSD approach.

  7. Different equation-of-motion coupled cluster methods with different reference functions: the formyl radical.

    PubMed

    Kuś, Tomasz; Bartlett, Rodney J

    2008-09-14

    The doublet and quartet excited states of the formyl radical have been studied by the equation-of-motion (EOM) coupled cluster (CC) method. The S(z) spin-conserving singles and doubles (EOM-EE-CCSD) and singles, doubles, and triples (EOM-EE-CCSDT) approaches, as well as the spin-flipped singles and doubles (EOM-SF-CCSD) method have been applied, subject to unrestricted Hartree-Fock (HF), restricted open-shell HF, and quasirestricted HF references. The structural parameters, vertical and adiabatic excitation energies, and harmonic vibrational frequencies have been calculated. The issue of the reference function choice for the spin-flipped (SF) method and its impact on the results has been discussed using the experimental data and theoretical results available. The results show that if the appropriate reference function is chosen so that target states differ from the reference by only single excitations, then EOM-EE-CCSD and EOM-SF-CCSD methods give a very good description of the excited states. For the states that have a non-negligible contribution of the doubly excited configurations one is able to use the SF method with such a reference function, that in most cases the performance of the EOM-SF-CCSD method is better than that of the EOM-EE-CCSD approach.

  8. [The EDQM Biological Standardisation Programme for the development of methods and reference preparations].

    PubMed

    Buchheit, K-H; Seitz, R

    2014-10-01

    The Biological Standardisation Programme (BSP) of the European Directorate for the Quality of Medicines & HealthCare (EDQM) was founded in 1992 with the objective to provide the necessary tools for the quality controls prescribed by the European Pharmacopoeia (Ph. Eur.). The BSP accomplishes this task by establishing reference standards and materials, as well as standardised control methods. A key aspect of BSP's work on development of methods is the validation of methods which can replace Ph. Eur. tests involving animals. The current area of work includes vaccines (for human and animal use), medicines produced from human plasma, hormones, cytokines, allergens, as well as reference materials and methods for determination of impurities and contaminations. BSP closely collaborates with the World Health Organization (WHO) and national authorities; many reference standards are established in joint projects with WHO. Participants of studies for establishing of reference materials and methods are mainly national control laboratories and manufacturers. BSP has to date run 131 projects, whereby 121 reference materials were established. Method development was the objective of 38 projects, with 21 thereof aiming at replacement of animal tests. BSP is funded by the EDQM (Council of Europe) and by the European Commission. With its activities BSP makes a significant contribution to quality, safety and efficacy of biological medicinal products in Europe and beyond, and serves thereby health and well-being of human beings and animals.

  9. MEASUREMENT OF VOLATILE ORGANIC COMPOUNDS BY THE US ENVIRONMENTAL PROTECTION AGENCY COMPENDIUM METHOD TO-17 - EVALUATION OF PERFORMANCE CRITERIA

    EPA Science Inventory

    An evaluation of performance criteria for US Environmental Protection Agency Compendium Method TO-17 for monitoring volatile organic compounds (VOCs) in air has been accomplished. The method is a solid adsorbent-based sampling and analytical procedure including performance crit...

  10. MEASUREMENT OF VOLATILE ORGANIC COMPOUNDS BY THE US ENVIRONMENTAL PROTECTION AGENCY COMPENDIUM METHOD TO-17 - EVALUATION OF PERFORMANCE CRITERIA

    EPA Science Inventory

    An evaluation of performance criteria for US Environmental Protection Agency Compendium Method TO-17 for monitoring volatile organic compounds (VOCs) in air has been accomplished. The method is a solid adsorbent-based sampling and analytical procedure including performance crit...

  11. Characterization of a measurement reference standard and neutron fluence determination method in IRSN monoenergetic neutron fields

    NASA Astrophysics Data System (ADS)

    Gressier, V.; Lacoste, V.; Martin, A.; Pepino, M.

    2014-10-01

    The variation in the response of instruments with neutron energy has to be determined in well-characterized monoenergetic neutron fields. The quantities associated with these fields are the neutron fluence and the mean energy of the monoenergetic neutron peak needed to determine the related dosimetric quantities. At the IRSN AMANDE facility, the reference measurement standard for neutron fluence is based on a long counter calibrated in the IRSN reference 252Cf neutron field. In this paper, the final characterization of this device is presented as well as the method used to determine the reference fluence at the calibration point in monoenergetic neutron fields.

  12. A terrain-dependent reference atmosphere determination method for available potential energy calculations

    NASA Technical Reports Server (NTRS)

    Koehler, T. L.

    1986-01-01

    An iterative technique that determines the reference atmosphere which incorporates the effects of uneven surface topography is presented. This method has been successfully applied in several available potential energy studies. An alternative method due to Taylor is also evaluated. While Taylor presented excellent continuous formulations of the available potential energy that include topography, his method for determining the reference atmosphere distributions failed to provide the accuracy needed to produce reliable available potential energy estimates. Since topography has a significant influence on the general circulation, it is important to employ techniques that incorporate its effects in the determination of available potential energy.

  13. Draft reference grid cells for emergency response reconnaissance developed for use by the US Environmental Protection Agency [ER.QUADS6K_EPA

    EPA Pesticide Factsheets

    Draft reference grid cells for emergency response reconnaissance developed for use by the US Environmental Protection Agency. Grid cells are based on densification of the USGS Quarterquad (1:12,000 scale or 12K) grids for the continental United States, Alaska, Hawaii and Puerto Rico and are roughly equivalent to 1:6000 scale (6K) quadrangles approximately 2 miles long on each side. Note: This file is >80MB in size. Regional subsets have been created from this national file that include a 20 mile buffer of tiles around each EPA Region. To access the regional subsets, go to http://geodata.epa.gov/OSWER/6kquads_epa.zip and select the name of the file that corresponds to your region of interest (e.g. 6kquadr1.zip is the name of the file created for EPA Region 1).

  14. An improved candidate reference method for serum potassium measurement by inductively coupled plasma-mass spectrometry.

    PubMed

    Zhang, Rui; Ma, Huaian; Li, Huiling; Xu, Jing; Zhang, Jianping; Zhang, Yang; Wang, Qingtao

    2013-05-01

    In 2002, the National Institute of Standards and Technology (NIST) established a reference method for serum potassium based on inductively coupled plasma-mass spectrometry (ICP-MS). The aim of this study was to develop an inexpensive and improved candidate reference method for accurate and precise determination of serum potassium. Serum samples were diluted with 1% HNO3 supplemented with (59)Cobalt as isotope internal standard, and potassium was measured by ICP-MS. The new method was evaluated with NIST standard reference materials (SRMs), according to the Clinical and Laboratory Standard Institute's evaluation protocols. At 4.300 and 4.678 mmol/l levels, the present method demonstrated analytical imprecision of 0.09% and 0.14%, and recoveries of 99.67% to 99.88%, respectively. The bias between the target values of SRMs were -0.02% to +0.28%, respectively. This method was linear between 0.0000 and 6.87 mmol/l (R(2)=1.000). The method had an uncertainty (U95%) of 0.76%. The proposed ICP-MS method to measure serum potassium is precise and accurate, with high sensitivity and specificity. It may be considered as a candidate reference method for the determination of serum potassium. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. 7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..._of_federal_regulations/ibr_locations.html. (2) The chemical reference starch determination used to... Association Method A-20, Analysis for Starch in Corn, Second revision, April 15, 1986, Standard Analytical... Method 992.23. (3) NIRS corn oil, protein, and starch analyzers. The maintenance tolerances for the NIRS...

  16. 7 CFR 801.7 - Reference methods and tolerances for near-infrared spectroscopy (NIRS) analyzers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..._of_federal_regulations/ibr_locations.html. (2) The chemical reference starch determination used to... Association Method A-20, Analysis for Starch in Corn, Second revision, April 15, 1986, Standard Analytical... Method 992.23. (3) NIRS corn oil, protein, and starch analyzers. The maintenance tolerances for the NIRS...

  17. A review and critique of the statistical methods used to generate reference values in pediatric echocardiography.

    PubMed

    Mawad, Wadi; Drolet, Christian; Dahdah, Nagib; Dallaire, Frederic

    2013-01-01

    Several articles have proposed echocardiographic reference values in normal pediatric subjects, but adequate validation is often lacking and has not been reviewed. The aim of this study was to review published reference values in pediatric two-dimensional and M-mode echocardiography with a specific focus on the adequacy of the statistical and mathematical methods used to normalize echocardiographic measurements. All articles proposing reference values for transthoracic pediatric echocardiography were reviewed. The types of measurements, the methods of normalization, the regression models used, and the methods used to detect potential bias in proposed reference values were abstracted. The detection of residual associations, residual heteroscedasticity, and departures from the normal distribution theory predictions were specifically analyzed. Fifty-two studies met the inclusion criteria. Most authors (87%) used parametric normalization to account for body size, but their approaches were very heterogeneous. Linear regression and indexing were the most common models. Heteroscedasticity was often present but was mentioned in only 27% of studies. The absence of residual heteroscedasticity and residual associations between the normalized measurements and the independent variables were mentioned in only 9% and 22% of the studies, respectively. Only 14% of studies documented that the distribution of the residual values was appropriate for Z score calculation or that the proportion of subjects falling outside the reference range was appropriate. Statistical suitability of the proposed reference ranges was often incompletely documented. This review underlines the great need for better standardization in echocardiographic measurement normalization.

  18. A minimal apparatus method for counting bacteria: comparison with reference method in surveying beef carcasses at three commercial abattoirs.

    PubMed Central

    Hudson, W. R.; Roberts, T. A.; Whelehan, O. P.

    1983-01-01

    In two surveys of three commercial abattoirs a minimal apparatus method for making bacterial counts, the "loop-tile' method, detected the same trends in bacterial numbers on beef carcasses as the ISO reference method applied to the same samples. Both methods showed the carcasses from one abattoir, that with an export license, to carry consistently higher numbers of bacteria, and one of the four sites sampled on each carcass to be consistently dirtier than the other three. PMID:6363526

  19. A systematic review of statistical methods used in constructing pediatric reference intervals.

    PubMed

    Daly, Caitlin H; Liu, Xiaofeng; Grey, Vijay L; Hamid, Jemila S

    2013-09-01

    This study aims to investigate current medical literature with focus on statistical methods used to construct pediatric reference intervals and identify potential gaps within the process of reference interval estimation. A systematic review of methods was performed. Extensive search criteria were developed and search was conducted on Embase, Medline, and PubMed databases to identify relevant articles. The articles were further screened using predefined inclusion and exclusion criteria. The selected articles were then included in our final systematic review. Our review reveals that there are gaps within current methodology and reporting of pediatric reference intervals. Not all publications followed the Clinical and Laboratory Standards Institute (CLSI) guidelines, and there is a large variation in the methods used. Discrepancies particularly arose when reference intervals were calculated for partitions with small sample sizes. In addition, the dynamic nature of pediatric data was not mostly captured when certain partitioning techniques were used. There are areas within the pediatric reference interval development process that need attention. Partitioning methods particularly need to be explored with the goals of reducing subjectivity and enabling researchers to capture the best representative partitions possible. Moreover, the complicated nature of pediatric data often limits the sample size available for each partition and appropriate methods need to be considered in such cases. Researchers are also strongly encouraged to accompany their reference limits with confidence intervals to show sampling variability and demonstrate precision of their limits. These issues exemplify the need for a pediatric specific guideline that outlines a standardized way of establishing reference intervals. Copyright © 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  20. PRELIMINARY RESULTS OF EPA'S PERFORMANCE EVALUATION OF FEDERAL REFERENCE METHODS AND FEDERAL EQUIVALENT METHODS FOR COARSE PARTICULATE MATTER

    EPA Science Inventory

    The main objective of this study is to evaluate the performance of sampling methods for potential use as a Federal Reference Method (FRM) capable of providing an estimate of coarse particle (PMc: particulate matter with an aerodynamic diameter between 2.5 µm and 10 µm) ...

  1. 41 CFR 302-5.13 - What methods may my agency use to reimburse me for househunting trip expenses?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... agency use to reimburse me for househunting trip expenses? 302-5.13 Section 302-5.13 Public Contracts and...) ALLOWANCES FOR SUBSISTENCE AND TRANSPORTATION EXPENSES 5-ALLOWANCE FOR HOUSEHUNTING TRIP EXPENSES Employee's Allowance For Househunting Trip Expenses § 302-5.13 What methods may my agency use to reimburse me for...

  2. 41 CFR 301-10.3 - What methods of transportation may my agency authorize me to use?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 4 2014-07-01 2014-07-01 false What methods of transportation may my agency authorize me to use? 301-10.3 Section 301-10.3 Public Contracts and Property... me to use? Your agency may authorize: (a) Common carrier transportation (e.g., aircraft, train, bus...

  3. 41 CFR 301-10.3 - What methods of transportation may my agency authorize me to use?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 4 2012-07-01 2012-07-01 false What methods of transportation may my agency authorize me to use? 301-10.3 Section 301-10.3 Public Contracts and Property... me to use? Your agency may authorize: (a) Common carrier transportation (e.g., aircraft, train, bus...

  4. 41 CFR 301-10.3 - What methods of transportation may my agency authorize me to use?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 4 2013-07-01 2012-07-01 true What methods of transportation may my agency authorize me to use? 301-10.3 Section 301-10.3 Public Contracts and Property... me to use? Your agency may authorize: (a) Common carrier transportation (e.g., aircraft, train, bus...

  5. Microhomogeneity in reference materials for microanalytical methods - a possible recourse from a blind alley?

    NASA Astrophysics Data System (ADS)

    Renno, A. D.; Michalak, P. P.; Munnik, F.; Tolosana-Delgado, R.; van den Boogaart, G. K.

    2013-12-01

    It is assumed that reference materials for microanalytical methods must be homogeneous, i.e. have the same concentration of the relevant element(s) overall, to ensure that they can be used reliably to get comparison values during the analysis with non absolute methods. With increasing resolution it becomes more and more difficult to ensure such homogeneity, up to the point that it is not possible for several microanalytical methods. Painstaking search for homogeneous natural minerals in gem quality or elaborate expensive methods to produce synthetic minerals provide as obvious solutions to the problem. We propose a way to get reliable reference values with some types of inhomogeneous material, based on multiple probing the reference material. Consider a reference material, which average concentration on the relevant element and its microscale variability has been adequately characterized by a destructive method at a series of grid spots. The minimal number of probing spots required for a certain precision level can be derived from the variance calculations. This procedure is always valid, whenever the heterogeneity value distribution of the reference material has a variance, but at the price that the number of spots will be huge if it is large. However, using adequate models of local heterogeneity can greatly reduce that number. Geostatistics can be used in random, systematic and periodic heterogeneities, while robust methods are useful in cases of nugget heterogeneities. Typical examples of natural and synthetic minerals, analysed by electron microprobe and micro-PIXE (particle induced X-ray emission) for microhomogeneity/microheterogeneity are shown. The distinctions between the two strategies of using these materials as a potential reference material are demonstrated.

  6. Primary reference cell calibrations at SERI - History and methods. [solar cells

    NASA Technical Reports Server (NTRS)

    Osterwald, C. R.; Emery, K. A.; Myers, D. R.; Hart, R. E.

    1990-01-01

    The tabular calibration method used at the Solar Energy Research Institute (SERI) for primary reference cells is derived and described in detail. An uncertainty analysis shows that the tabular method should have a total uncertainty of + or - 1.0 percent; data from five years of calibrations are then shown to support this analysis. Results from SERI's tabular method are compared with terrestrial calibrations performed by the NASA Lewis Research Center in the late 1970s.

  7. A novel method for the activity measurement of large-area beta reference sources.

    PubMed

    Stanga, D; De Felice, P; Keightley, J; Capogni, M; Ioan, M R

    2016-03-01

    A novel method has been developed for the activity measurement of large-area beta reference sources. It makes use of two emission rate measurements and is based on the weak dependence between the source activity and the activity distribution for a given value of transmission coefficient. The method was checked experimentally by measuring the activity of two ((60)Co and (137)Cs) large-area reference sources constructed from anodized aluminum foils. Measurement results were compared with the activity values measured by gamma spectrometry. For each source, they agree within one standard uncertainty and also agree within the same limits with the certified values of the source activity.

  8. Method of multiple references for 3D imaging with Fourier transform interferometry.

    PubMed

    Lally, Evan; Gong, Jianmin; Wang, Anbo

    2010-08-16

    This letter presents an improved phase referencing technique, called Method of Multiple References, for optical profilometry. Based on a lookup table, the method eliminates several major drawbacks of single-reference Fourier Transform Interferometry by enabling surface error correction for steep slopes and step discontinuities, and by allowing mapping of multiple discrete objects using a single image set. The algorithm is tested using a fiber optic coupler-based FTI system and shown to have RMS surface error less than 0.03 mm.

  9. Perturbative universal state-selective correction for state-specific multi-reference coupled cluster methods

    SciTech Connect

    Brabec, Jiri; Banik, Subrata; Kowalski, Karol; Pittner, Jiří

    2016-10-28

    The implementation details of the universal state-selective (USS) multi-reference coupled cluster (MRCC) formalism with singles and doubles (USS(2)) are discussed on the example of several benchmark systems. We demonstrate that the USS(2) formalism is capable of improving accuracies of state specific multi-reference coupled-cluster (MRCC) methods based on the Brillouin-Wigner and Mukherjee’s sufficiency conditions. Additionally, it is shown that the USS(2) approach significantly alleviates problems associated with the lack of invariance of MRCC theories upon the rotation of active orbitals. We also discuss the perturbative USS(2) formulations that significantly reduce numerical overhead of the full USS(2) method.

  10. Validation of a reference method for total cholesterol measurement in human serum and assignation of reference values to proficiency testing samples.

    PubMed

    Heuillet, Maud; Lalere, Beatrice; Peignaux, Maryline; De Graeve, Jacques; Vaslin-Reimann, Sophie; Pais De Barros, Jean-Paul; Gambert, Philippe; Duvillard, Laurence; Delatour, Vincent

    2013-03-01

    Our objective was to develop a reference method to measure total cholesterol in human serum, in order to assign values and assess the accuracy of field methods in French clinical laboratories. A reference method based on gas chromatography coupled with mass spectrometry and isotope dilution (GC-IDMS) was developed and validated. It was then used to assign reference values to five frozen serum samples from voluntary proficiency testing schemes gathering 170 French clinical laboratories. Three peer groups were defined and bias against the reference method target value was calculated. Accuracy of the reference method was assessed against NIST SRM 1951b. Bias of the reference method was less than 0.5% and imprecision was less than 1.0%. Our study indicated that field methods tended to overestimate total cholesterol concentration, mean bias being +5.02% ± 1.02%. The most popular methods (phenolic chromogen with spectrophotometric detection, 80% of participants) exhibited the highest bias (peer group mean bias: +5.51 ± 1.24%). Neither these methods nor those using a non-phenolic chromogen with reflectometric detection (10% of participants, peer group mean bias: +4.20 ± 1.44%) met NCEP recommendations according to which bias should be less than 3%. Only the methods using a non phenolic chromogen with a spectrophotometric detection met these recommendations (10% of participants, peer group mean bias: +1.39 ± 2.75%). As all three peer groups provided positively biased results, the consensus mean usually used to assess the trueness of routine methods is biased as well, which results in an erroneous estimation of method bias. Therefore, this study highlights the value added by reference method target values to assess trueness of field methods and monitor performance of clinical laboratories. Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  11. 20 CFR 411.400 - Can an EN to which a beneficiary's ticket is assigned refer the beneficiary to a State VR agency...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...' Benefits SOCIAL SECURITY ADMINISTRATION THE TICKET TO WORK AND SELF-SUFFICIENCY PROGRAM State Vocational Rehabilitation Agencies' Participation Referrals by Employment Networks to State Vr Agencies § 411.400 Can an EN... beneficiary to the State VR agency for services. Agreements Between Employment Networks and State VR Agencies...

  12. 20 CFR 411.400 - Can an EN to which a beneficiary's ticket is assigned refer the beneficiary to a State VR agency...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...' Benefits SOCIAL SECURITY ADMINISTRATION THE TICKET TO WORK AND SELF-SUFFICIENCY PROGRAM State Vocational Rehabilitation Agencies' Participation Referrals by Employment Networks to State Vr Agencies § 411.400 Can an EN... beneficiary to the State VR agency for services. Agreements Between Employment Networks and State VR Agencies...

  13. A Dynamic Selection Method for Reference Electrode in SSVEP-Based BCI

    PubMed Central

    Wu, Zhenghua; Su, Sheng

    2014-01-01

    In SSVEP-based Brain-Computer Interface (BCI), it is very important to get an evoked EEG with a high signal to noise ratio (SNR). The SNR of SSVEP is fundamentally related to the characteristics of stimulus, such as its intensity and frequency, and it is also related to both the reference electrode and the active electrode. In the past, with SSVEP-based BCI, often the potential at ‘Cz’, the average potential at all electrodes or the average mastoid potential, were statically selected as the reference. In conjunction, a certain electrode in the occipital area was statically selected as the active electrode for all stimuli. This work proposed a dynamic selection method for the reference electrode, in which all electrodes can be looked upon as active electrodes, while an electrode which can result in the maximum sum relative-power of a specific frequency SSVEP can be confirmed dynamically and considered as the optimum reference electrode for that specific frequency stimulus. Comparing this dynamic selection method with previous methods, in which ‘Cz’, the average potential at all electrodes or the average mastoid potential were selected as the reference electrode, it is demonstrated that the SNR of SSVEP is improved significantly as is the accuracy of SSVEP detection. PMID:25100038

  14. A dynamic selection method for reference electrode in SSVEP-based BCI.

    PubMed

    Wu, Zhenghua; Su, Sheng

    2014-01-01

    In SSVEP-based Brain-Computer Interface (BCI), it is very important to get an evoked EEG with a high signal to noise ratio (SNR). The SNR of SSVEP is fundamentally related to the characteristics of stimulus, such as its intensity and frequency, and it is also related to both the reference electrode and the active electrode. In the past, with SSVEP-based BCI, often the potential at 'Cz', the average potential at all electrodes or the average mastoid potential, were statically selected as the reference. In conjunction, a certain electrode in the occipital area was statically selected as the active electrode for all stimuli. This work proposed a dynamic selection method for the reference electrode, in which all electrodes can be looked upon as active electrodes, while an electrode which can result in the maximum sum relative-power of a specific frequency SSVEP can be confirmed dynamically and considered as the optimum reference electrode for that specific frequency stimulus. Comparing this dynamic selection method with previous methods, in which 'Cz', the average potential at all electrodes or the average mastoid potential were selected as the reference electrode, it is demonstrated that the SNR of SSVEP is improved significantly as is the accuracy of SSVEP detection.

  15. A method of synthesis magnetotelluric time-series combining interstation transfer functions and a reference site

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Campanyà, Joan

    2016-04-01

    A new method to Synthesis magnetotelluric (MT) data is proposed whereby the MT Time-series of local site are derived using an Inverse Fourier transform of electric and magnetic fields spectrum of local site, which are computed by Combining Interstation transfer functions and a Reference horizontal magnetic time series (STICIR). The method is based on the stability of interstation transfer function, assuming that the geoelectrical structures of the subsurface independent of time. Applying the suggested method, two interstation transfer functions need to be estimated: the quasi-MT impedance tensor and the interstation geomagnetic transfer functions, which are used to compute the horizontal electric fields and the vertical magnetic field at the local site, respectively. The interstation transfer functions can be estimated by single site robust or remote reference (RR) method if another reference site existed. STICIR provides a new way to synthesis MT time-series at the local site combining interstation transfer functions and the magnetic fields at a reference site. Due to this property, STICIR provides significant improvements processing MT data when time-series at the local site are affected by local noise or are truncated. A test with good quality of MT data shows that synthetic time-series are similar to natural electric and magnetic time series. For contaminated data example, when this method is used to remove noise present at the local site, the scatter of MT sounding curves are clear reduced, and the low frequency data quality are improved.

  16. Performance of the Proposed New Federal Reference Methods for Measuring Ozone Concentrations in Ambient Air

    EPA Science Inventory

    The current Federal Reference Method (FRM) for measuring concentrations of ozone in ambient air, described in EPA regulations at 40 CFR Part 50, Appendix D, is based on the dry, gas-phase, chemiluminescence reaction between ethylene (C2H4) and any ozone (O

  17. FIELD PERFORMANCE OF PM 2.5 FEDERAL REFERENCE METHOD SAMPLERS

    EPA Science Inventory

    The results of several research field studies were evaluated to estimate the precision and bias of various designated PM2.5 Federal Reference Method (FRM) samplers. Precision was high in three carefully conducted research studies where all operational activities were strictly ...

  18. Development of a zero-method interferometer by means of dynamic generation of reference wave front

    NASA Astrophysics Data System (ADS)

    Hanayama, Ryohei; Ishii, Katsuhiro

    2013-04-01

    In this report, we propose a zero-method interferometer by means of dynamic generation of reference wave front using liquid crystal type spatial light modulator (LCoS-SLM). This interferometer was developed to aim to measure the shape of complex plane, such as aspherical plane. It is difficult for interferometer to measure such a surface which include large inclination, because of the problem of saturation of interference fringe. To overcome this problem, and to enlarge the dynamic range of interferometer, we attempted to combine interferometer and zero-method. Zero-method is characterized by its wide dynamic range. To apply zero-method to interferometer, SLM is adopted to configure variable reference surface. The basic configuration of the developed interferometer is Twyman-Green interferometer. A SLM is placed instead of reference mirror. In this interferometer, the shape of a target is measured using interference between object wave front and reference wave front that is generated using SLM. At first, the SLM generates flat wave front. And the detected phase map is fed back to the SLM. Then the difference between object wave front and detected phase map in the first turn. The operation is recursively repeated until the phase range of detected phase map becomes under the threshold. Then the generated wave front should become equal to the target shape. In this report, the basic idea of zeromethod interferometer using LCoS-SLM is verified through several numbers of simulative experiments.

  19. Performance of the Proposed New Federal Reference Methods for Measuring Ozone Concentrations in Ambient Air

    EPA Science Inventory

    The current Federal Reference Method (FRM) for measuring concentrations of ozone in ambient air, described in EPA regulations at 40 CFR Part 50, Appendix D, is based on the dry, gas-phase, chemiluminescence reaction between ethylene (C2H4) and any ozone (O

  20. Review of Federal Reference Method for Ozone: Nitric Oxide-Chemiluminescence:Supplemental Material for CASAC AMMS

    EPA Science Inventory

    ApproachPer suggestion made by CASAC AMMS members during the April 3, 2014 conference call on the Review of Federal Reference Method for Ozone: Nitric Oxide-Chemiluminescence, ORD has performed additional data analysis activities to explain and mitigate scatter observed in the co...

  1. WFC3/IR Reference Pixel Characterization #1: Comparison of Bias Subtraction Methods

    NASA Astrophysics Data System (ADS)

    Hilbert, B.

    2012-03-01

    In this first of two ISRs about the WFC3/IR reference pixel performance, we compare five different methods for using the reference pixels on the detector to remove bias signal from the measured signal in the light-sensitive science pixels. None of these methods produce a significant improvement over the current approach in the calwf3 calibration pipeline. We also note the existence of an extra signal in addition to the bias signal in the inboard reference pixels. Thought to be a "signal memory", this signal was observed in ground tests of early, non-flight detectors but was thought not to be present in the current flight detector. The extra signal does not degrade the WFC3/IR calibration. Large (~100DN), long-lasting (~weeks) signal jumps in a subset of the reference pixels as well as nearby science pixels were also observed. A subsequent ISR will report on efforts to characterize these jumps and the long-term behavior of the reference pixels.

  2. A preliminary verification of the floating reference measurement method for non-invasive blood glucose sensing

    NASA Astrophysics Data System (ADS)

    Min, Xiaolin; Liu, Rong; Fu, Bo; Xu, Kexin

    2017-06-01

    In the non-invasive sensing of blood glucose by near-infrared diffuse reflectance spectroscopy, the spectrum is highly susceptible to the unstable and complicated background variations from the human body and the environment. In in vitro analyses, background variations are usually corrected by the spectrum of a standard reference sample that has similar optical properties to the analyte of interest. However, it is hard to find a standard sample for the in vivo measurement. Therefore, the floating reference measurement method is proposed to enable relative measurements in vivo, where the spectra under some special source-detector distance, defined as the floating reference position, are insensitive to the changes in glucose concentration due to the absorption effect and scattering effect. Because the diffuse reflectance signals at the floating reference positions only reflect the information on background variations during the measurement, they can be used as the internal reference. In this paper, the theoretical basis of the floating reference positions in a semi-infinite turbid medium was discussed based on the steady-state diffusion equation and its analytical solutions in a semi-infinite turbid medium (under the extrapolated boundary conditions). Then, Monte-Carlo (MC) simulations and in vitro experiments based on a custom-built continuous-moving spatially resolving double-fiber NIR measurement system, configured with two types of light source, a super luminescent diode (SLD) and a super-continuum laser, were carried out to verify the existence of the floating reference position in 5%, 10% and 20% Intralipid solutions. The results showed that the simulation values of the floating reference positions are close to the theoretical results, with a maximum deviation of approximately 0.3 mm in 1100-1320 nm. Great differences can be observed in 1340-1400 nm because the optical properties of Intralipid in this region don not satisfy the conditions of the steady

  3. References concerning birth control methods in Ancient Indian Classics: an exposition.

    PubMed

    Srikanth, N

    2000-01-01

    Reproduction is the basic phenomenon of Biological activity. Like other living beings man has a desire to reproduce. Unlike others he can control reproduction at his will. From early vedic periods belonging to several centuries prior to Christian era, we find references concerning methods of controlling the population over growth. Views of vedic sages, sexologists of ancient and medieval India regarding the birth control methods are expressed in this presentation.

  4. A comprehensive method for identification of suitable reference genes in extracellular vesicles

    PubMed Central

    Gouin, Kenneth; Peck, Kiel; Antes, Travis; Johnson, Jennifer Leigh; Li, Chang; Vaturi, Sharon Denise; Middleton, Ryan; de Couto, Geoff; Walravens, Ann-Sophie; Rodriguez-Borlado, Luis; Smith, Rachel Ruckdeschel; Marbán, Linda; Marbán, Eduardo; Ibrahim, Ahmed Gamal-Eldin

    2017-01-01

    ABSTRACT Reverse transcription–quantitative polymerase chain reaction (RT-qPCR) is one of the most sensitive, economical and widely used methods for evaluating gene expression. However, the utility of this method continues to be undermined by a number of challenges including normalization using appropriate reference genes. The need to develop tailored and effective strategies is further underscored by the burgeoning field of extracellular vesicle (EV) biology. EVs contain unique signatures of small RNAs including microRNAs (miRs). In this study we develop and validate a comprehensive strategy for identifying highly stable reference genes in a therapeutically relevant cell type, cardiosphere-derived cells. Data were analysed using the four major approaches for reference gene evaluation: NormFinder, GeNorm, BestKeeper and the Delta Ct method. The weighted geometric mean of all of these methods was obtained for the final ranking. Analysis of RNA sequencing identified miR-101-3p, miR-23a-3p and a previously identified EV reference gene, miR-26a-5p. Analysis of a chip-based method (NanoString) identified miR-23a, miR-217 and miR-379 as stable candidates. RT-qPCR validation revealed that the mean of miR-23a-3p, miR-101-3p and miR-26a-5p was the most stable normalization strategy. Here, we demonstrate that a comprehensive approach of a diverse data set of conditions using multiple algorithms reliably identifies stable reference genes which will increase the utility of gene expression evaluation of therapeutically relevant EVs. PMID:28815002

  5. Analysis of 70 Environmental Protection Agency priority pharmaceuticals in water by EPA Method 1694.

    PubMed

    Ferrer, Imma; Zweigenbaum, Jerry A; Thurman, E Michael

    2010-09-03

    The U.S. Environmental Protection Agency (EPA) Method 1694 for the determination of pharmaceuticals in water recently brought a new challenge for treatment utilities, where pharmaceuticals have been reported in the drinking water of 41-million Americans. This proposed methodology, designed to address this important issue, consists of solid-phase extraction (SPE) followed by liquid chromatography-mass spectrometry (LC/MS-MS) using triple quadrupole. Under the guidelines of Method 1694, a multi-residue method was developed, validated, and applied to wastewater, surface water and drinking water samples for the analysis of 70 pharmaceuticals. Four distinct chromatographic gradients and LC conditions were used according to the polarity and extraction of the different pharmaceuticals. Positive and negative ion electrospray were used with two MRM transitions (a quantifier and a qualifier ion for each compound), which adds extra confirmation not included in the original Method 1694. Finally, we verify, for the first time, EPA Method 1694 on water samples collected in several locations in Colorado, where positive identifications for several pharmaceuticals were found. This study is a valuable indicator of the potential of LC/MS-MS for routine quantitative multi-residue analysis of pharmaceuticals in drinking water and wastewater samples and will make monitoring studies much easier to develop for water utilities across the US, who are currently seeking guidance on analytical methods for pharmaceuticals in their water supplies. 2010 Elsevier B.V. All rights reserved.

  6. The method of testing of the attitude reference systems with optoelectronic sensors

    NASA Astrophysics Data System (ADS)

    Szelmanowski, Andrzej; Michalak, Slawomir

    2003-09-01

    What the paper deals with is the method of testing of the attitude reference systems with the coning excitation/motion applied. A theoretical description of the excitation at issue has been given and followed with a comparative analysis of the excitation generated in the UPG-48 station with a tilting platform. Experimental data of testing of the attitude and heading reference system AHRS LCR-92 system for the non-holonomical excitation/motion have been compared with results effected by some simulation-based tests of numerical models of the attitude and heading reference systems with the optoelectronic sensors. On the grounds of some numerical-simulation-effected findings gained with the AutoCAD packet, a concept of a coning-excitation-generating measuring station has been developed at the Air Force Institute of Technology and presented in this paper.

  7. 78 FR 67360 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of Five New Equivalent Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-12

    ... an automated method (analyzer) utilizing the principle of Cavity Attenuated Phase Shift spectroscopy... shift spectroscopy Nitrogen Dioxide Analyzer'', operated on any full scale range between 0-500 ppb and...

  8. Statistical methods for evaluating the attainment of cleanup standards. Volume 3, Reference-based standards for soils and solid media, Revision 1

    SciTech Connect

    Gilbert, R.O.; Simpson, J.C.

    1992-12-01

    This document is the third volume in a series of volumes sponsored by the US Environmental Protection Agency (EPA), Statistical Policy Branch, that provide statistical methods for evaluating the attainment of cleanup Standards at Superfund sites. Volume 1 (USEPA 1989a) provides sampling designs and tests for evaluating attainment of risk-based standards for soils and solid media. Volume 2 (USEPA 1992) provides designs and tests for evaluating attainment of risk-based standards for groundwater. The purpose of this third volume is to provide statistical procedures for designing sampling programs and conducting statistical tests to determine whether pollution parameters in remediated soils and solid media at Superfund sites attain site-specific reference-based standards. This.document is written for individuals who may not have extensive training or experience with statistical methods. The intended audience includes EPA regional remedial project managers, Superfund-site potentially responsible parties, state environmental protection agencies, and contractors for these groups.

  9. Methods for TEM analysis of NIST's single-walled carbon nanotube Standard Reference Material

    NASA Astrophysics Data System (ADS)

    Mansfield, Elisabeth; Geiss, Roy; Fagan, Jeffrey A.

    2009-08-01

    The National Institute of Standards and Technology (NIST) will soon release a series of single-walled carbon nanotube (SWCNT) reference materials (RMs) to provide users with a well-characterized material for their applications. The SWCNT reference material will be introduced as a series of three types of material: (1) raw soot characterized for composition, which will be certified as a Standard Reference Material, (2) purified (greater than 90 % SWCNT by weight) bucky paper and (3) dispersed, length-sorted populations characterized by length. The instrumental characterization of NIST's SWCNT reference materials is extensive, and this paper aims to provide researchers with dispersion preparation methods for TEM (transmission electron microscopy) analysis of the SWCNT raw soot. A selection of dispersing solvents, including organic solvents, aqueous surfactants and DNA dispersions, were prepared and examined by TEM. Recommendations for sample preparation of the SWCNT SRM 2483 to yield images similar to those presented here are given. Examples of images of the length-sorted SWCNT reference material are also shown. These results illustrate the importance of optimal dispersion to enable imaging of SWCNT characteristics.

  10. Determination of asbestos fibres in air transmission electron microscopy as a reference method

    NASA Astrophysics Data System (ADS)

    Steen, Dieter; Guillemin, Michel P.; Buffat, Phillipe; Gilbert, Litzistorf

    Asbestos fibres are present everywhere in our environment. A series of questions concerning, for example, their toxicity or their acceptable levels still remain unanswered. The elaboration of an as accurate as possible reference method for the determination of mineral fibres in air which would be sensitive enough for use in environments with a very low level of contamination is thus called for. From a very short survey of the available methods it can be concluded that a transmission electron microscopy (TEM) method fulfils these requirements. This method is very long and expensive and should be used only in those environments where the level of fibres is low, or in complicated situations where a reference method is required. In other types of environments, such as occupational or paraoccupational situations, other less accurate but more rapid and convenient methods may be used. It is stressed that for any of these methods, and especially for the TEM method, a detailed standardization of the procedure is essential. As a scanning electron microscopy (SEM) method has also been considered for monitoring the ambient environment, the characteristics of both methods are compared, illustrated by photomicrographs and discussed. A TEM method is described in detail as follows: sampling (included recommended air volumes for different contaminated areas), sample treatment, mounting of collected fibres on electron microscopy grids, identification and counting, expression of results and detection limit. Finally, this method is applied to two different paraoccupational situations: two buildings insulated with asbestos. It is then compared with other, more simple methods. For the case of the air contaminated by long fibres (mostly crocidolite) the agreement between the different methods is fairly good. However, for the case where the fibres are short (mixture of man-made mineral fibres and chrysotile) this is not true. These differences are discussed and it is concluded that the

  11. Are human service agencies ready for disasters? Findings from a mixed-methods needs assessment and planning project.

    PubMed

    Hipper, Thomas J; Orr, Ashley; Chernak, Esther

    2015-01-01

    A mixed-methods design was used to assess the current capacity of human service agencies to provide services in a major disaster, identify challenges and successful strategies for providing those services, and formulate specific recommendations for government planners and the nonprofit sector to promote the integration of human service agencies into emergency preparedness and response. A web-based survey was completed by 188 unique human service agencies, 31 semistructured interviews were conducted with human service agency and government leaders from southeastern Pennsylvania and the mid-Atlantic region, and a collaborative planning meeting was held to review the findings and develop systems-based recommendations. Survey results indicated that human service agencies serve the most vulnerable communities during disasters and would welcome integration into preparedness and response plans, but they currently face challenges that include a lack of real-time communication and opportunities for collaborative planning with government partners. Interview findings were grouped according to 5 themes that emerged: capacity, coordination, communication, training, and leadership. This study identified recommendations to assist human service agencies, local health departments, and emergency management agencies as they work to ensure that needed human services are available during disasters, despite the resource challenges that most agencies face.

  12. Calibration method for the reference parameter in Fernald and Klett inversion combining Raman and Elastic return

    NASA Astrophysics Data System (ADS)

    Ji, Hongzhu; Chen, Siying; Zhang, Yinchao; Chen, He; Guo, Pan; Chen, Hao

    2017-02-01

    A calibration method is proposed to invert the extinction coefficient for Fernald and Klett inversion by using the particle backscattering coefficient inversed with Raman and Elastic return signals. The calibration method is analyzed theoretically and experimentally, the inversion accuracy can be improved by removing the dependence on reference altitudes and intervals in conventional calibration methods, which resulted from the introduction of backscattering coefficient with relatively higher accuracy obtained by Raman-Mie inversion method. The standard deviation of this new calibration method can be reduced by about 20×, compared to that of the conventional calibration methods of Fernald and Klett inversion. And, the more stable effective inversed range with this new calibration method can be obtained by removing the dimple phenomenon in clouds position.

  13. The establishment of tocopherol reference intervals for Hungarian adult population using a validated HPLC method.

    PubMed

    Veres, Gábor; Szpisjak, László; Bajtai, Attila; Siska, Andrea; Klivényi, Péter; Ilisz, István; Földesi, Imre; Vécsei, László; Zádori, Dénes

    2017-02-09

    Evidence suggests that decreased α-tocopherol (the most biologically active substance in the vitamin E group) level can cause neurological symptoms, most likely ataxia. The aim of the current study was to first provide reference intervals for serum tocopherols in the adult Hungarian population with appropriate sample size, recruiting healthy control subjects and neurological patients suffering from conditions without symptoms of ataxia, myopathy or cognitive deficiency. A validated HPLC method applying a diode array detector and rac-tocol as internal standard was utilized for that purpose. Furthermore, serum cholesterol levels were determined as well for data normalization. The calculated 2.5-97.5% reference intervals for α-, β/γ- and δ-tocopherols were 24.62-54.67, 0.81-3.69 and 0.29-1.07 μm, respectively, whereas the tocopherol/cholesterol ratios were 5.11-11.27, 0.14-0.72 and 0.06-0.22 μmol/mmol, respectively. The establishment of these reference intervals may improve the diagnostic accuracy of tocopherol measurements in certain neurological conditions with decreased tocopherol levels. Moreover, the current study draws special attention to the possible pitfalls in the complex process of the determination of reference intervals as well, including the selection of study population, the application of internal standard and method validation and the calculation of tocopherol/cholesterol ratios.

  14. GMOMETHODS: the European Union database of reference methods for GMO analysis.

    PubMed

    Bonfini, Laura; Van den Bulcke, Marc H; Mazzara, Marco; Ben, Enrico; Patak, Alexandre

    2012-01-01

    In order to provide reliable and harmonized information on methods for GMO (genetically modified organism) analysis we have published a database called "GMOMETHODS" that supplies information on PCR assays validated according to the principles and requirements of ISO 5725 and/or the International Union of Pure and Applied Chemistry protocol. In addition, the database contains methods that have been verified by the European Union Reference Laboratory for Genetically Modified Food and Feed in the context of compliance with an European Union legislative act. The web application provides search capabilities to retrieve primers and probes sequence information on the available methods. It further supplies core data required by analytical labs to carry out GM tests and comprises information on the applied reference material and plasmid standards. The GMOMETHODS database currently contains 118 different PCR methods allowing identification of 51 single GM events and 18 taxon-specific genes in a sample. It also provides screening assays for detection of eight different genetic elements commonly used for the development of GMOs. The application is referred to by the Biosafety Clearing House, a global mechanism set up by the Cartagena Protocol on Biosafety to facilitate the exchange of information on Living Modified Organisms. The publication of the GMOMETHODS database can be considered an important step toward worldwide standardization and harmonization in GMO analysis.

  15. Nonlinear Performance Seeking Control using Fuzzy Model Reference Learning Control and the Method of Steepest Descent

    NASA Technical Reports Server (NTRS)

    Kopasakis, George

    1997-01-01

    Performance Seeking Control (PSC) attempts to find and control the process at the operating condition that will generate maximum performance. In this paper a nonlinear multivariable PSC methodology will be developed, utilizing the Fuzzy Model Reference Learning Control (FMRLC) and the method of Steepest Descent or Gradient (SDG). This PSC control methodology employs the SDG method to find the operating condition that will generate maximum performance. This operating condition is in turn passed to the FMRLC controller as a set point for the control of the process. The conventional SDG algorithm is modified in this paper in order for convergence to occur monotonically. For the FMRLC control, the conventional fuzzy model reference learning control methodology is utilized, with guidelines generated here for effective tuning of the FMRLC controller.

  16. NDE of additively manufactured components with embedded defects (reference standards) using conventional and advanced ultrasonic methods

    NASA Astrophysics Data System (ADS)

    Koester, L.; Roberts, R. A.; Barnard, D. J.; Chakrapani, S.; Singh, S.; Hogan, R.; Bond, L. J.

    2017-02-01

    Additive manufacturing provides a unique opportunity to embed defects of known size and shape to produce reference samples for inspection and quality control purposes. This paper reports defect detectability studies with cylindrical additively manufactured cobalt-chromium alloy specimens which contain defects of known sizes and distributions. The specimens were characterized using immersion, synthetic aperture focusing (SAFT), phased array, and nonlinear ultrasonic techniques. Results include detectability, signal to noise ratios, and comparison of results between the methods and what is believed to be the first determination of a non-linearity (beta) parameter for an additively manufactured material. The results indicate that additive manufacturing provides a valuable method to produce reference samples, though additional work is required to validate the shape and morphology of the defects specified.

  17. Massively parallel implementation of the multi-reference Brillouin-Wigner CCSD method

    SciTech Connect

    Brabec, Jiri; Krishnamoorthy, Sriram; van Dam, Hubertus JJ; Kowalski, Karol; Pittner, Jiri

    2011-10-06

    This paper reports the parallel implementation of the Brillouin Wigner MultiReference Coupled Cluster method with Single and Double excitations (BW-MRCCSD). Preliminary tests for systems composed of 304 and 440 correlated obritals demonstrate the performance of our implementation across 1000 cores and clearly indicate the advantages of using improved task scheduling. Possible ways for further improvements of the parallel performance are also delineated.

  18. Verification of chemistry reference ranges using a simple method in sub-Saharan Africa

    PubMed Central

    Taylor, Douglas; Mandala, Justin; Nanda, Kavita; Van Campenhout, Christel; Agingu, Walter; Madurai, Lorna; Barsch, Eva-Maria; Deese, Jennifer; Van Damme, Lut; Crucitti, Tania

    2016-01-01

    Background Chemistry safety assessments are interpreted by using chemistry reference ranges (CRRs). Verification of CRRs is time consuming and often requires a statistical background. Objectives We report on an easy and cost-saving method to verify CRRs. Methods Using a former method introduced by Sigma Diagnostics, three study sites in sub-Saharan Africa, Bondo, Kenya, and Pretoria and Bloemfontein, South Africa, verified the CRRs for hepatic and renal biochemistry assays performed during a clinical trial of HIV antiretroviral pre-exposure prophylaxis. The aspartate aminotransferase/alanine aminotransferase, creatinine and phosphorus results from 10 clinically-healthy participants at the screening visit were used. In the event the CRRs did not pass the verification, new CRRs had to be calculated based on 40 clinically-healthy participants. Results Within a few weeks, the study sites accomplished verification of the CRRs without additional costs. The aspartate aminotransferase reference ranges for the Bondo, Kenya site and the alanine aminotransferase reference ranges for the Pretoria, South Africa site required adjustment. The phosphorus CRR passed verification and the creatinine CRR required adjustment at every site. The newly-established CRR intervals were narrower than the CRRs used previously at these study sites due to decreases in the upper limits of the reference ranges. As a result, more toxicities were detected. Conclusion To ensure the safety of clinical trial participants, verification of CRRs should be standard practice in clinical trials conducted in settings where the CRR has not been validated for the local population. This verification method is simple, inexpensive, and can be performed by any medical laboratory. PMID:28879112

  19. A reference image-based method for optimization of clinical immunohistochemistry.

    PubMed

    Kap, Marcel; Lam, King H; Ewing-Graham, Patricia; Riegman, Peter

    2015-08-01

    Cold ischaemic and formalin fixation time (CIT and FFT) are considered to be crucial parameters for intralaboratory variation in immunohistochemistry (IHC). Here we describe a new method to optimize IHC, by using control tissue blocks with known pre-analytical history and comparing the IHC outcome with digitized reference slides. Tissue specimens (two per tissue type) were divided into eight samples, which were subjected to different CIT and FFT. Immunohistochemistry was performed with 34 routinely used antibodies, following standard operating procedures. Relative staining intensity of four sections per slide was scored. Of the antibodies studied, seven were influenced by CIT, 13 by FFT and five by both parameters. IHC protocols were adapted until most sections on the slide showed the same intensity. Changing the antibody dilution for 10 protocols and the antigen retrieval method for six protocols improved the consistency of the IHC staining. Nine protocols could not be optimized. The optimized staining results were compared to reference slides and were found to be of adequate quality. It was possible to optimize most IHC protocols by adapting the analytical, rather than the pre-analytical, phase. If global references can be established, this method could decrease interlaboratory variation, preceding standardization of the pre-analytical workflow. © 2015 John Wiley & Sons Ltd.

  20. A reference-wavelength-based method for improved analysis of near-infrared spectroscopy.

    PubMed

    Chen, Yun; Chen, Wenliang; Shi, Zhenzhi; Yang, Yue; Xu, Kexin

    2009-05-01

    Near-infrared (NIR) spectroscopy has been widely used in many industrial applications. It also has tremendous potential for trace element detection and noninvasive human physiological measurements. In NIR spectroscopy, however, the measurement precision is often dependent on temperature, measurement position, and sample status. In order to improve measurement precision, a method using spectral information at a reference wavelength is developed in this paper. Based on the displacement effect between solvent and solute molecules in a solution, the signal at the reference wavelength is used as an internal reference to correct the spectrum of the sample under test. As an example, the spectra of glucose aqueous solutions under different temperatures are measured, and our method for eliminating the temperature disturbance is evaluated. The experimental results obtained show that the relative error of glucose concentration prediction is 330% per degree before the spectrum correction. After the correction, the relative error is reduced to 5.12%, and the error is no longer dependent on temperature. As the displacement effect can be found commonly in various solutions, the method described in this work may be used to improve the accuracy of spectral analysis of many other solutions.

  1. [Study on temperature measurement of solution by reference-wavelength method].

    PubMed

    Chen, Yun; Liang, Yu-Jie; Chen, Wen-Liang; Xu, Ke-Xin

    2009-10-01

    Near-infrared (NIR) spectroscopy has been widely used in agriculture, medicine, petrochemical and food industries. However, the measurement precision of NIR spectroscopy is adversely affected by the change in external conditions. Among these influence factors, temperature fluctuation is harder to be controlled than other conditions such as contact pressure and measurement position. Based on the displacement effect between solvent and solute molecules in solution, a reference-wavelength method for temperature measurement of solution is presented in the present paper. The theoretical expression of the method was introduced. The experiment was designed to measure the spectra of glucose aqueous solution under different temperatures, and the effect of eliminating the temperature disturbance was evaluated. When the temperature and solute concentration of solution change simultaneously, the absorbency difference value at reference-wavelength is insensitive to solute concentration, and is totally affected by temperature fluctuation. Therefore, according to the absorbance difference, the actual temperature of the sample can be calculated. The regression model of temperature measurement was established, and the solution temperature was calculated based on this model. The information about temperature can be acquired exactly by reference-wavelength method, and the experimental results showed that the average error of calculated temperafure is 0.03 degree C.

  2. Glossary of reference terms for alternative test methods and their validation.

    PubMed

    Ferrario, Daniele; Brustio, Roberta; Hartung, Thomas

    2014-01-01

    This glossary was developed to provide technical references to support work in the field of the alternatives to animal testing. It was compiled from various existing reference documents coming from different sources and is meant to be a point of reference on alternatives to animal testing. Giving the ever-increasing number of alternative test methods and approaches being developed over the last decades, a combination, revision, and harmonization of earlier published collections of terms used in the validation of such methods is required. The need to update previous glossary efforts came from the acknowledgement that new words have emerged with the development of new approaches, while others have become obsolete, and the meaning of some terms has partially changed over time. With this glossary we intend to provide guidance on issues related to the validation of new or updated testing methods consistent with current approaches. Moreover, because of new developments and technologies, a glossary needs to be a living, constantly updated document. An Internet-based version based on this compilation may be found at http://altweb.jhsph.edu/, allowing the addition of new material.

  3. TANK OPERATIONS CONTRACT CONSTRUCTION MANAGEMENT METHODOLOGY UTILIZING THE AGENCY METHOD OF CONSTRUCTION MANAGEMENT

    SciTech Connect

    LESKO KF; BERRIOCHOA MV

    2010-02-26

    Washington River Protection Solutions, LLC (WRPS) has faced significant project management challenges in managing Davis-Bacon construction work that meets contractually required small business goals. The unique challenge is to provide contracting opportunities to multiple small business constructioin subcontractors while performing high hazard work in a safe and productive manner. Previous to the WRPS contract, construction work at the Hanford Tank Farms was contracted to large companies, while current Department of Energy (DOE) Contracts typically emphasize small business awards. As an integral part of Nuclear Project Management at Hanford Tank Farms, construction involves removal of old equipment and structures and installation of new infrastructure to support waste retrieval and waste feed delivery to the Waste Treatment Plant. Utilizing the optimum construction approach ensures that the contractors responsible for this work are successful in meeting safety, quality, cost and schedule objectives while working in a very hazardous environment. This paper descirbes the successful transition from a traditional project delivery method that utilized a large business general contractor and subcontractors to a new project construction management model that is more oriented to small businesses. Construction has selected the Agency Construction Management Method (John E Schaufelberger, Len Holm, "Management of Construction Projects, A Constructor's Perspective", University of Washington, Prentice Hall 2002). This method was implemented in the first quarter of Fiscal Year 2009 (FY2009), where Construction Management is performed by substantially home office resources from the URS Northwest Office in Richland, Washington. The Agency Method has allowed WRPS to provide proven Construction Managers and Field Leads to mentor and direct small business contractors, thus providing expertise and assurance of a successful project. Construction execution contracts are subcontracted

  4. Washout allometric reference method (WARM) for parametric analysis of [(11)C]PIB in human brains.

    PubMed

    Rodell, Anders; Aanerud, Joel; Braendgaard, Hans; Gjedde, Albert

    2013-01-01

    Rapid clearance and disappearance of a tracer from the circulation challenges the determination of the tracer's binding potentials in brain (BP ND) by positron emission tomography (PET). This is the case for the analysis of the binding of radiolabeled [(11)C]Pittsburgh Compound B ([(11)C]PIB) to amyloid-β (Aβ) plaques in brain of patients with Alzheimer's disease (AD). To resolve the issue of rapid clearance from the circulation, we here introduce the flow-independent Washout Allometric Reference Method (WARM) for the analysis of washout and binding of [(11)C]PIB in two groups of human subjects, healthy aged control subjects (HC), and patients suffering from AD, and we compare the results to the outcome of two conventional analysis methods. We also use the rapid initial clearance to obtain a surrogate measure of the rate of cerebral blood flow (CBF), as well as a method of identifying a suitable reference region directly from the [(11)C]PIB signal. The difference of average absolute CBF values between the AD and HC groups was highly significant (P < 0.003). The CBF measures were not significantly different between the groups when normalized to cerebellar gray matter flow. Thus, when flow differences confound conventional measures of [(11)C]PIB binding, the separate estimates of CBF and BP ND provide additional information about possible AD. The results demonstrate the importance of data-driven estimation of CBF and BP ND, as well as reference region detection from the [(11)C]PIB signal. We conclude that the WARM method yields stable measures of BP ND with relative ease, using only integration for noise reduction and no model regression. The method accounts for relative flow differences in the brain tissue and yields a calibrated measure of absolute CBF directly from the [(11)C]PIB signal. Compared to conventional methods, WARM optimizes the Aβ plaque load discrimination between patients with AD and healthy controls (P = 0.009).

  5. RBS as a new primary direct reference method for measuring quantity of material

    NASA Astrophysics Data System (ADS)

    Jeynes, C.

    2017-09-01

    The quantity of material in thin films can be measured reliably, non-destructively, and at an absolute traceable accuracy with a combined standard uncertainty of 1% by Rutherford backscattering spectrometry (RBS). We have demonstrated a measurement protocol for the determination of quantity of material by RBS that has been accredited at this accuracy to the ISO 17025 standard by the United Kingdom Accreditation Service (UKAS). The method is entirely traceable to SI units relying on no artefacts, and thus qualifies as a primary direct reference method as defined by the ISO Guide 35:1985 (paragraph 9.4.1).

  6. A standard setting method with the best performing students as point of reference: practical and affordable.

    PubMed

    Cohen-Schotanus, Janke; van der Vleuten, Cees P M

    2010-01-01

    Teachers involved in test development usually prefer criterion-referenced standard setting methods using panels. Since expert panels are costly, standards are often set by a pre-fixed percentage of questions answered correctly or norm-referenced methods aimed at ranking examinees. To discuss the (dis)advantages of commonly used criterion and norm-referenced methods and present a new compromise method: standards based on a fixed cut-off score using the best scoring students as reference point. Historical data from 54 Maastricht (norm-referenced) and 52 Groningen (criterion-referenced) tests were used to demonstrate huge discrepancies and variability in cut-off scores and failure rates. Subsequently, the compromise model - known as Cohen's method - was applied to the Groningen tests. The Maastricht norm-referenced method led to a large variation in required cut-off scores (15-46%), but a stable failure rate (about 17%). The Groningen method with a conventional, pre-fixed standard of 60% led to a large variation in failure rates (17-97%). The compromise method reduced variation in required cut-off scores as well as failure rates. Both the criterion and norm-referenced standards, used in practice, have disadvantages. The proposed compromise model reduces the disadvantages of both methods and is considered more acceptable. Last but not least, compared to standard setting methods using panels, this method is affordable.

  7. Reference-free, high-resolution measurement method of timing jitter spectra of optical frequency combs

    PubMed Central

    Kwon, Dohyeon; Jeon, Chan-Gi; Shin, Junho; Heo, Myoung-Sun; Park, Sang Eon; Song, Youjian; Kim, Jungwon

    2017-01-01

    Timing jitter is one of the most important properties of femtosecond mode-locked lasers and optical frequency combs. Accurate measurement of timing jitter power spectral density (PSD) is a critical prerequisite for optimizing overall noise performance and further advancing comb applications both in the time and frequency domains. Commonly used jitter measurement methods require a reference mode-locked laser with timing jitter similar to or lower than that of the laser-under-test, which is a demanding requirement for many laser laboratories, and/or have limited measurement resolution. Here we show a high-resolution and reference-source-free measurement method of timing jitter spectra of optical frequency combs using an optical fibre delay line and optical carrier interference. The demonstrated method works well for both mode-locked oscillators and supercontinua, with 2 × 10−9 fs2/Hz (equivalent to −174 dBc/Hz at 10-GHz carrier frequency) measurement noise floor. The demonstrated method can serve as a simple and powerful characterization tool for timing jitter PSDs of various comb sources including mode-locked oscillators, supercontinua and recently emerging Kerr-frequency combs; the jitter measurement results enabled by our method will provide new insights for understanding and optimizing timing noise in such comb sources. PMID:28102352

  8. Reference-free, high-resolution measurement method of timing jitter spectra of optical frequency combs

    NASA Astrophysics Data System (ADS)

    Kwon, Dohyeon; Jeon, Chan-Gi; Shin, Junho; Heo, Myoung-Sun; Park, Sang Eon; Song, Youjian; Kim, Jungwon

    2017-01-01

    Timing jitter is one of the most important properties of femtosecond mode-locked lasers and optical frequency combs. Accurate measurement of timing jitter power spectral density (PSD) is a critical prerequisite for optimizing overall noise performance and further advancing comb applications both in the time and frequency domains. Commonly used jitter measurement methods require a reference mode-locked laser with timing jitter similar to or lower than that of the laser-under-test, which is a demanding requirement for many laser laboratories, and/or have limited measurement resolution. Here we show a high-resolution and reference-source-free measurement method of timing jitter spectra of optical frequency combs using an optical fibre delay line and optical carrier interference. The demonstrated method works well for both mode-locked oscillators and supercontinua, with 2 × 10‑9 fs2/Hz (equivalent to ‑174 dBc/Hz at 10-GHz carrier frequency) measurement noise floor. The demonstrated method can serve as a simple and powerful characterization tool for timing jitter PSDs of various comb sources including mode-locked oscillators, supercontinua and recently emerging Kerr-frequency combs; the jitter measurement results enabled by our method will provide new insights for understanding and optimizing timing noise in such comb sources.

  9. Efficient implementation of the three-dimensional reference interaction site model method in the fragment molecular orbital method

    SciTech Connect

    Yoshida, Norio

    2014-06-07

    The three-dimensional reference interaction site model (3D-RISM) method was efficiently implemented in the fragment molecular orbital (FMO) method. The method is referred to as the FMO/3D-RISM method, and allows us to treat electronic structure of the whole of a macromolecule, such as a protein, as well as the solvent distribution around a solute macromolecule. The formalism of the FMO/3D-RISM method, for the computationally available form and variational expressions, are proposed in detail. A major concern leading to the implementation of the method was decreasing the computational costs involved in calculating the electrostatic potential, because the electrostatic potential is calculated on numerous grid points in three-dimensional real space in the 3D-RISM method. In this article, we propose a procedure for decreasing the computational costs involved in calculating the electrostatic potential in the FMO method framework. The strategy involved in this procedure is to evaluate the electrostatic potential and the solvated Fock matrix in different manners, depending on the distance between the solute and the solvent. The electrostatic potential is evaluated directly in the vicinity of the solute molecule by integrating the molecular orbitals of monomer fragments of the solute molecule, whereas the electrostatic potential is described as the sum of multipole interactions when an analog of the fast multipole method is used. The efficiency of our method was demonstrated by applying it to a water trimer system and three biomolecular systems. The FMO/3D-RISM calculation can be performed within a reasonable computational time, retaining the accuracy of some physical properties.

  10. Reference Phantom Method for Acoustic Backscatter Coefficient and Attenuation Coefficient Measurements.

    NASA Astrophysics Data System (ADS)

    Yao, Linxin

    1990-08-01

    In previous work in our laboratory accurate backscatter coefficient measurements were obtained with a data reduction method that explicitly accounts for experimental factors involved in recording echo data. An alternative, relative processing method for determining the backscatter coefficient and the attenuation coefficient is presented here. This method involves comparison of echo data from a sample with data recorded from a reference phantom whose backscatter and attenuation coefficients are known. The ratio of the signals cancels depth-dependent instrumentation factors. This saves the efforts of beam profile computation and various calibrations. The attenuation coefficient and backscatter coefficient of the sample are found from these ratios and the known acoustic properties of the reference phantom. This method is tested using tissue-mimicking phantoms with known scattering and attenuation properties. Various experiments have been done using clinical scanners with different transducers to compute attenuation coefficients and backscatter coefficients, and to make quantitative images. This method has been found to be accurate for media containing Rayleigh scatterers, as well as samples containing intermediate-size scatterers. Accuracy was maintained over different frequency bands and for a wide range of transducer-to-ROI distances. Measurements were done in vivo for human livers, kidneys and dog myocardium. The results have shown that the reference phantom method simplifies the measurement procedure as well as keeps the accuracy, and therefore is practical clinically. Statistical uncertainties propagated in the data reduction have been analyzed in detail. Formulae are deduced to predict statistical errors in the attenuation and backscatter coefficients measured with the reference phantom method. Spatial correlations of the echo signals are also considered. A 2-dimensional lateral correlation matrix is introduced to compute the number of effective independent

  11. ANSI/ASHRAE/IES Standard 90.1-2010 Performance Rating Method Reference Manual

    SciTech Connect

    Goel, Supriya; Rosenberg, Michael I.

    2016-05-01

    This document is intended to be a reference manual for the Appendix G Performance Rating Method (PRM) of ANSI/ASHRAE/IES Standard 90.1- 2010 (Standard 90.1-2010).The PRM is used for rating the energy efficiency of commercial and high-rise residential buildings with designs that exceed the requirements of Standard 90.1. The procedures and processes described in this manual are designed to provide consistency and accuracy by filling in gaps and providing additional details needed by users of the PRM. It should be noted that this document is created independently from ASHRAE and SSPC 90.1 and is not sanctioned nor approved by either of those entities . Potential users of this manual include energy modelers, software developers and implementers of “beyond code” energy programs. Energy modelers using ASHRAE Standard 90.1-2010 for beyond code programs can use this document as a reference manual for interpreting requirements of the Performance Rating method. Software developers, developing tools for automated creation of the baseline model can use this reference manual as a guideline for developing the rules for the baseline model.

  12. Design of two-dimensional zero reference codes with cross-entropy method.

    PubMed

    Chen, Jung-Chieh; Wen, Chao-Kai

    2010-06-20

    We present a cross-entropy (CE)-based method for the design of optimum two-dimensional (2D) zero reference codes (ZRCs) in order to generate a zero reference signal for a grating measurement system and achieve absolute position, a coordinate origin, or a machine home position. In the absence of diffraction effects, the 2D ZRC design problem is known as the autocorrelation approximation. Based on the properties of the autocorrelation function, the design of the 2D ZRC is first formulated as a particular combination optimization problem. The CE method is then applied to search for an optimal 2D ZRC and thus obtain the desirable zero reference signal. Computer simulation results indicate that there are 15.38% and 14.29% reductions in the second maxima value for the 16x16 grating system with n(1)=64 and the 100x100 grating system with n(1)=300, respectively, where n(1) is the number of transparent pixels, compared with those of the conventional genetic algorithm.

  13. Resampling approach for determination of the method for reference interval calculation in clinical laboratory practice.

    PubMed

    Pavlov, Igor Y; Wilson, Andrew R; Delgado, Julio C

    2010-08-01

    Reference intervals (RI) play a key role in clinical interpretation of laboratory test results. Numerous articles are devoted to analyzing and discussing various methods of RI determination. The two most widely used approaches are the parametric method, which assumes data normality, and a nonparametric, rank-based procedure. The decision about which method to use is usually made arbitrarily. The goal of this study was to demonstrate that using a resampling approach for the comparison of RI determination techniques could help researchers select the right procedure. Three methods of RI calculation-parametric, transformed parametric, and quantile-based bootstrapping-were applied to multiple random samples drawn from 81 values of complement factor B observations and from a computer-simulated normally distributed population. It was shown that differences in RI between legitimate methods could be up to 20% and even more. The transformed parametric method was found to be the best method for the calculation of RI of non-normally distributed factor B estimations, producing an unbiased RI and the lowest confidence limits and interquartile ranges. For a simulated Gaussian population, parametric calculations, as expected, were the best; quantile-based bootstrapping produced biased results at low sample sizes, and the transformed parametric method generated heavily biased RI. The resampling approach could help compare different RI calculation methods. An algorithm showing a resampling procedure for choosing the appropriate method for RI calculations is included.

  14. Resampling Approach for Determination of the Method for Reference Interval Calculation in Clinical Laboratory Practice▿

    PubMed Central

    Pavlov, Igor Y.; Wilson, Andrew R.; Delgado, Julio C.

    2010-01-01

    Reference intervals (RI) play a key role in clinical interpretation of laboratory test results. Numerous articles are devoted to analyzing and discussing various methods of RI determination. The two most widely used approaches are the parametric method, which assumes data normality, and a nonparametric, rank-based procedure. The decision about which method to use is usually made arbitrarily. The goal of this study was to demonstrate that using a resampling approach for the comparison of RI determination techniques could help researchers select the right procedure. Three methods of RI calculation—parametric, transformed parametric, and quantile-based bootstrapping—were applied to multiple random samples drawn from 81 values of complement factor B observations and from a computer-simulated normally distributed population. It was shown that differences in RI between legitimate methods could be up to 20% and even more. The transformed parametric method was found to be the best method for the calculation of RI of non-normally distributed factor B estimations, producing an unbiased RI and the lowest confidence limits and interquartile ranges. For a simulated Gaussian population, parametric calculations, as expected, were the best; quantile-based bootstrapping produced biased results at low sample sizes, and the transformed parametric method generated heavily biased RI. The resampling approach could help compare different RI calculation methods. An algorithm showing a resampling procedure for choosing the appropriate method for RI calculations is included. PMID:20554803

  15. Comparison of analytical methods for the determination of histamine in reference canned fish samples

    NASA Astrophysics Data System (ADS)

    Jakšić, S.; Baloš, M. Ž.; Mihaljev, Ž.; Prodanov Radulović, J.; Nešić, K.

    2017-09-01

    Two screening methods for histamine in canned fish, an enzymatic test and a competitive direct enzyme-linked immunosorbent assay (CD-ELISA), were compared with the reversed-phase liquid chromatography (RP-HPLC) standard method. For enzymatic and CD-ELISA methods, determination was conducted according to producers’ manuals. For RP-HPLC, histamine was derivatized with dansyl-chloride, followed by RP-HPLC and diode array detection. Results of analysis of canned fish, supplied as reference samples for proficiency testing, showed good agreement when histamine was present at higher concentrations (above 100 mg kg‑1). At a lower level (16.95 mg kg‑1), the enzymatic test produced some higher results. Generally, analysis of four reference samples according to CD-ELISA and RP-HPLC showed good agreement for histamine determination (r=0.977 in concentration range 16.95–216 mg kg‑1) The results show that the applied enzymatic test and CD-ELISA appeared to be suitable screening methods for the determination of histamine in canned fish.

  16. Evaluation of different methods to estimate daily reference evapotranspiration in ungauged basins in Southern Brazil

    NASA Astrophysics Data System (ADS)

    Ribeiro Fontoura, Jessica; Allasia, Daniel; Herbstrith Froemming, Gabriel; Freitas Ferreira, Pedro; Tassi, Rutineia

    2016-04-01

    Evapotranspiration is a key process of hydrological cycle and a sole term that links land surface water balance and land surface energy balance. Due to the higher information requirements of the Penman-Monteith method and the existing data uncertainty, simplified empirical methods for calculating potential and actual evapotranspiration are widely used in hydrological models. This is especially important in Brazil, where the monitoring of meteorological data is precarious. In this study were compared different methods for estimating evapotranspiration for Rio Grande do Sul, the Southernmost State of Brazil, aiming to suggest alternatives to the recommended method (Penman-Monteith-FAO 56) for estimate daily reference evapotranspiration (ETo) when meteorological data is missing or not available. The input dataset included daily and hourly-observed data from conventional and automatic weather stations respectively maintained by the National Weather Institute of Brazil (INMET) from the period of 1 January 2007 to 31 January 2010. Dataset included maximum temperature (Tmax, °C), minimum temperature (Tmin, °C), mean relative humidity (%), wind speed at 2 m height (u2, m s-1), daily solar radiation (Rs, MJ m- 2) and atmospheric pressure (kPa) that were grouped at daily time-step. Was tested the Food and Agriculture Organization of the United Nations (FAO) Penman-Monteith method (PM) at its full form, against PM assuming missing several variables not normally available in Brazil in order to calculate daily reference ETo. Missing variables were estimated as suggested in FAO56 publication or from climatological means. Furthermore, PM was also compared against the following simplified empirical methods: Hargreaves-Samani, Priestley-Taylor, Mccloud, McGuiness-Bordne, Romanenko, Radiation-Temperature, Tanner-Pelton. The statistical analysis indicates that even if just Tmin and Tmax are available, it is better to use PM estimating missing variables from syntetic data than

  17. Potential methods and perspectives of solar energy conversion via photocatalytic processes. [345 references

    SciTech Connect

    Zamaraev, K.I.; Parmon, V.N.

    1980-01-01

    Existing methods of solar energy conversion are classified into 4 types: (1) thermal; (2) photophysical; (3) photochemical (including photoelectrolysis); and (4) photobiological (based on natural photosynthesis). Thermal conversion under direct conditions is an attractive method of conversion, but further conversion of heat into mechanical or electrical energy make thermal conversion seem unsuitable for large-scale use. Methods based on direct conversion into electrical or chemical energy of fossil fuels make them much more attractive for large scale use. For high efficiency of solar energy conversion, the development of moleuclar photocatalytic systems for solar energy conversion - a kind of simplified analog to natural photosynthesizing systems seem very attractive. For obtaining the highest possible efficiency, systems which do not involve free radicals and free atom intermediates appear to be the most advantageous. 345 references. (BLM)

  18. An induction method to calculate the complex permeability of soft magnetic films without a reference sample.

    PubMed

    Wei, Jinwu; Wang, Jianbo; Liu, Qingfang; Li, Xiaoyu; Cao, Derang; Sun, Xiaojun

    2014-05-01

    A new analytical method has been proposed by utilizing an electromagnetic induction principle with a short-circuited microstrip line jig and the complex permeability spectra can be calculated without a known reference sample. The new method using the short-circuited microstrip line can exhibit higher sensitivity and a wider frequency band than coplanar waveguide and pick-up coil. Two magnetic thin films having a good in-plane uniaxial anisotropy are measured by using the induction method. The results show typical complex permeability spectra in good agreement with the theoretical analytical results. The measured permeability values are verified by comparing with the initial susceptibility derived from the sweeping field results. The difference of measured permeability values is less than 5%.

  19. Modeling an Alternative Reference Evapotranspiration Method under Different Climate Regimes in Brazil

    NASA Astrophysics Data System (ADS)

    Jerszurki, D.; Souza, J. L. M.; Silva, L. C. R.; Gurski, B. C.

    2016-12-01

    The development and validation of new reference evapotranspiration (ETo) methods hold significant promise for an improved quantitative understanding of terrestrial water fluxes to the atmosphere. To address a critical gap in knowledge, concerning the general absence of adequate alternative ETo estimations for tropical and subtropical regions, generated a new reference method "Moretti-Jerszurki", based on atmospheric water potential (Ψair) and solar radiation (Ra) data. We adjusted and evaluated this physical ETo method for the most representative climate types of Brazil. We compared our results with standard EToPM (Penman-Monteith) estimates performed between 2004 and 2014, using air temperature (T), sunshine hours (n), relative humidity (RH) and wind speed (U2). The new method was proposed and analyzed in two different scenarios, based: (i) only on Ψair (EToMJ(Ψair)); and, (ii) Ψair and Ra (EToMJ and EToMJc). Least square regression analysis of Ψair vs EToPM and EToMJ vs EToPM were used to calibrate the EToMJ(Ψair) and EToMJc methods, respectively. The performance of calibrated methods EToMJ(Ψair) and EToMJc was evaluated by index of agreement "d" and performance "c", root mean square error (RMSE), mean absolute error (MAE) and mean reason (MR). Preliminary results across a wide range of tropical and subtropical climates are promising and indicate a strong linear association with standard EToPM. The EToMJ(Ψair) was particularly robust in tropical and semi-arid climates, outlining the importance of continuous measurements of T and RH used in the Ψair modeling effort. We recommend the use of EToMJc for most humid climate types in the region, but simplified EToMJ(Ψair) estimates are better suited to estimate water fluxes in arid and semi-arid regions.

  20. Solar collector test procedures: Development of a method to refer measured efficiencies to standardized test conditions

    NASA Astrophysics Data System (ADS)

    Thomas, W. C.

    1984-02-01

    An analytical procedure has been developed for referring collector efficiency measurements, obtained under different test conditions, to a common, or standard set of conditions. The procedure applies to flatplate liquid-type collectors of conventional tube-in-sheet design. The basic Hottel-Whillier-Bliss theory is used with appropriate extensions to account for serpentine flow configurations and glazing materials with high infrared transmittance. The procedure includes a systematic method for deriving two invariant collector parameters directly from ASHRAE Standard 93-77 test results. The two parameters selected are the plate absorptance and back loss coefficient. A set of standard conditions is recommended which corresponds to favorable test conditions.

  1. A method to obtain reference images for evaluation of ultrasonic tissue characterization techniques.

    PubMed

    Jensen, M S; Wilhjelm, J E; Sahl, B; Brandt, T; Martinsen, K; Jespersen, S K; Falk, E

    2002-05-01

    A general problem when evaluating ultrasonic methods for tissue characterization is that "a golden standard" is seldom known. This paper describes a manual method to obtain a reference image, with the same geometry as the ultrasound image, indicating spatial location of the different tissue types present in the biological tissue scanned in vitro. A 30 x 10 x 2 mm3 piece of formalin fixed porcine tissue was molded into an agar block, which on the top surface, contained a set of fiducial markers, spaced 2.5 mm. The block was submerged into 20 degrees C water and a set of parallel 7.5 MHz spatial compound ultrasound images of tissue and fiducial markers were recorded each 0.5 mm. Guided by the fiducial markers, the agar block was subsequently cut into slices 2.5 mm thick, photographed and finally analyzed histologically identifying these tissues: collagen rich, collagen poor, micro vessels and muscle fibres. Due to: (1) the cutting procedure, (2) the finite size of the ultrasound beam and (3) the spatial variation in propagation velocity, the macroscopic photographs did not align completely with the ultrasound images. Likewise, the histological image is a geometrically distorted version of the macroscopic photograph, due to the histological preparation process. The histological information was "mapped back" into the format of the ultrasound images the following way: On the macroscopic images, outlines were drawn manually which defined the border of the tissue. These outlines were superimposed on the corresponding ultrasound images (identified via the fiducial markers) and modified to encompass what appeared to be tissue regions on the ultrasound images and subsequently re-applied to the macroscopic image. This modified macroscopic outline was used as guideline when drawing outlines identifying regions of the various tissue types. Specifically, the macroscopic image revealed the borders between the different tissues, while the histological image identified the four

  2. Assessment of air quality microsensors versus reference methods: The EuNetAir joint exercise

    NASA Astrophysics Data System (ADS)

    Borrego, C.; Costa, A. M.; Ginja, J.; Amorim, M.; Coutinho, M.; Karatzas, K.; Sioumis, Th.; Katsifarakis, N.; Konstantinidis, K.; De Vito, S.; Esposito, E.; Smith, P.; André, N.; Gérard, P.; Francis, L. A.; Castell, N.; Schneider, P.; Viana, M.; Minguillón, M. C.; Reimringer, W.; Otjes, R. P.; von Sicard, O.; Pohle, R.; Elen, B.; Suriano, D.; Pfister, V.; Prato, M.; Dipinto, S.; Penza, M.

    2016-12-01

    The 1st EuNetAir Air Quality Joint Intercomparison Exercise organized in Aveiro (Portugal) from 13th-27th October 2014, focused on the evaluation and assessment of environmental gas, particulate matter (PM) and meteorological microsensors, versus standard air quality reference methods through an experimental urban air quality monitoring campaign. The IDAD-Institute of Environment and Development Air Quality Mobile Laboratory was placed at an urban traffic location in the city centre of Aveiro to conduct continuous measurements with standard equipment and reference analysers for CO, NOx, O3, SO2, PM10, PM2.5, temperature, humidity, wind speed and direction, solar radiation and precipitation. The comparison of the sensor data generated by different microsensor-systems installed side-by-side with reference analysers, contributes to the assessment of the performance and the accuracy of microsensor-systems in a real-world context, and supports their calibration and further development. The overall performance of the sensors in terms of their statistical metrics and measurement profile indicates significant differences in the results depending on the platform and on the sensors considered. In terms of pollutants, some promising results were observed for O3 (r2: 0.12-0.77), CO (r2: 0.53-0.87), and NO2 (r2: 0.02-0.89). For PM (r2: 0.07-0.36) and SO2 (r2: 0.09-0.20) the results show a poor performance with low correlation coefficients between the reference and microsensor measurements. These field observations under specific environmental conditions suggest that the relevant microsensor platforms, if supported by the proper post processing and data modelling tools, have enormous potential for new strategies in air quality control.

  3. Experimental test results from an environmental protection agency test method for determination of vapor suppressant effectiveness

    NASA Astrophysics Data System (ADS)

    Tock, Richard W.; Ahern, Daniel W.

    2005-04-01

    The results obtained from laboratory experiments conducted using Environmental Protection Agency (EPA) subpart WWWW of 40 Code of Federal Regulations (CFR) part 63 (1)-test method are discussed in this article. The original test method was developed to measure the effectiveness of wax suppressants used to reduce hazardous air pollutant (HAP) emissions from unsaturated polyester (UP)/vinyl ester resins. Wax additions of ˜1.5% by weight to commercial UP resins suppress HAP emissions through the formation of surface barrier films. However, the tests performed in this study included the use of limestone and an adjunct, organic fiber reinforcement, rather than the wax. The addition of either commercial product to the UP formulations tested in this study was also shown to reduce HAP emissions. Suppression was a combination of absorption and an increased diffusion path barrier for the volatile organic carbon (VOC) components. Based on the limited data obtained, it was shown that the oil absorption characteristics of the two adjunct products could be used to estimate the expected level of vapor suppression for a specific resin formulation. Values reported in the literature for the oil adsorption characteristics of the adjunct limestone and the commercial biomass fiber were used in the laboratory tests. Although the oil adsorption characteristic of any ingredient added to a base resin formulation is indicative of its potential for emissions reduction, the EPA test protocol is still required to be performed for validation. Such screening tests will always be needed due to the variability associated with commercial UP resins and the evolution of customized UP/fiberglass composite formulations developed by custom molding shops.

  4. A Method for Evaluating Outcomes of Restoration When No Reference Sites Exist

    Treesearch

    J. Stephen Brewer; Timothy. Menzel

    2009-01-01

    Ecological restoration typically seeks to shift species composition toward that of existing reference sites. Yet, comparing the assemblages in restored and reference habitats assumes that similarity to the reference habitat is the optimal outcome of restoration and does not provide a perspective on regionally rare off-site species. When no such reference assemblages of...

  5. A virtual reference satellite differential method for relative correction of satellite ephemeris errors

    NASA Astrophysics Data System (ADS)

    Cai, Chenglin; Li, Xiaohui; Wu, Haitao

    2010-12-01

    In order to solve the problems that the novel wide area differential method on the satellite clock and ephemeris relative correction (CERC) in the non-geostationary orbit satellite constellation, a virtual reference satellite (VRS) differential principle using relative correction of satellite ephemeris errors is proposed. It is referred to be as the VRS differential principle, and the elaboration is focused on the construction of pseudo-range errors of VRS. Through qualitative analysis, it can be found that the impact of the satellite's clock and ephemeris errors on positioning can basically be removed and the users' positioning errors are near zero. Through simulation analysis of the differential performance, it is verified that the differential method is universal in all kinds of satellite navigation systems with geostationary orbit (GEO) constellation, Medium orbit (MEO) constellation or hybrid orbit constellation, and it has insensitivity to abnormal aspects of a satellite ephemeris and clock. Moreover, the real time positioning accuracy of differential users can be maintained within several decimeters after the pseudo-range measurement noise is effectively weakened or eliminated.

  6. Reference sample method reduces the error caused by variable cryosection thickness in Fourier transform infrared imaging.

    PubMed

    Rieppo, Jarno; Hyttinen, Mika M; Jurvelin, Jukka S; Helminen, Heikki J

    2004-01-01

    Fourier transform infrared imaging (FT-IRI) is a novel technique for characterization of the biochemical composition of biological tissues, e.g., articular cartilage. The use of cryosections is preferred in FT-IRI. Unfortunately, significant variation in section thickness often impairs the suitability of cryosections for quantitative FT-IRI analysis. The present study introduces an inexpensive reference sample method for quantitative analysis. In this technique, specimen absorption is normalized with that of nitrocellulose membrane embedded and cryosectioned with the sample. Mean variation of the infrared absorption in cartilage specimens was 11.5%, 12.1%, and 20.6% for 5 microm, 10 microm, and 14 microm thick sections, respectively, without normalization. Normalization reduced the variation to 5.2%, 4.0%, and 4.6% for the same sections, respectively. The normalization method enables usage of cryosections for quantitative work and significantly reduces the cost and time needed for FT-IRI analysis.

  7. COMPARISON OF MENTEROCOCCUS AGAR AND THE U.S. ENVIRONMENTAL PROTECTION AGENCY-RECOMENDED ENTEROCOCCI METHODS, ME AND MEI AGAR

    EPA Science Inventory

    To maintain waters that are "fishable and swimmable", mandated by the Clean Water Act, the U.S. Environmental Protection Agency (EPA) is developing a list of approved methods for use in enumerating enterococci and E. coli in ambient waters. As part of this effort, we compared mEn...

  8. An Innovative Method for Evaluating Strategic Goals in a Public Agency: Conservation Leadership in the U.S. Forest Service.

    ERIC Educational Resources Information Center

    Bengston, David N.; Fan, David P.

    1999-01-01

    Presents an innovative methodology for evaluating strategic goals in a public agency. The method involves computer content analysis of online news media text to evaluate expressed attitudes. Provides a way to assess the views of a wide range of stakeholders quickly and efficiently. (SLD)

  9. A proposed reference method for plasminogen activators that enables calculation of enzyme activities in SI units.

    PubMed

    Longstaff, C; Whitton, C M

    2004-08-01

    A method has been developed for accurately and precisely measuring the activity of a range of plasminogen activators (PAs) used as thrombolytic agents, including streptokinase, tissue plasminogen activator (tPA) and variants, and urokinase (uPA), both single and two chain forms. Plasminogen activation is monitored in a transparent, solid fibrin matrix but uses chromogenic substrate hydrolysis, rather than changes in fibrin, to quantitate the activity of PAs. The method has been tested in two recent international collaborative studies involving tPA and streptokinase where it has been shown to perform very well. Furthermore, the method is based on sound enzymological principles and once correction for the competitive inhibition of fibrin(ogen) is made, the generation of plasmin can be determined in molar terms and hence the activity of PAs can be expressed and compared in SI units (rate of increase in molar concentration of plasmin) as well as International Units. The assay is also arranged in such a way to reflect the behavior of PAs in vivo during thrombolytic therapy and it is shown that the specific activity of streptokinase and tPA in this system reflects plasmin generation capacity of these thrombolytics for doses given in infusions for treatment of myocardial infarction. The method would make a suitable reference method for PAs and provides a rigorous means of studying and modeling the enzymology of fibrinolysis and will be helpful in the rational design of third generation thrombolytic agents.

  10. Total cholesterol performance of Abell-Levy-Brodie-Kendall reference measurement procedure: Certification of Japanese in-vitro diagnostic assay manufacturers through CDC's Cholesterol Reference Method Laboratory Network.

    PubMed

    Nakamura, Masakazu; Iso, Hiroyasu; Kitamura, Akihiko; Imano, Hironori; Kiyama, Masahiko; Yokoyama, Shinji; Kayamori, Yuzo; Koyama, Isao; Nishimura, Kunihiro; Nakai, Michikazu; Dasti, Mahnaz; Vesper, Hubert W; Teramoto, Tamio; Miyamoto, Yoshihiro

    2015-05-20

    Accurate measurement of total cholesterol (TC) is important for cardiovascular disease risk management. The US Centers for Disease Control and Prevention (CDC) and Cholesterol Reference Method Laboratory Network (CRMLN) perform Abell-Levy-Brodie-Kendall (AK) reference measurement procedure (RMP) for TC as a secondary reference method, and implement Certification Protocol for Manufacturers. Japanese CRMLN laboratory at Osaka performed the AK RMP for 22 years, and conducted TC certification for reagent/calibrator/instrument systems of six Japanese manufacturers every 2 years for 16 years. Osaka TC performance was examined and compared to CDC's reference values. AK RMP involved sample hydrolysis, cholesterol extraction, and determination of cholesterol levels by spectrophotometry. The Certification Protocol for Manufacturers includes comparison with AK RMP using at least 40 fresh specimens. Demonstration of average bias ≤3% and total coefficient of variation ≤3% qualified an analytical system for certification. In the AK RMP used in the Osaka CRMLN laboratory, the regression equation for measuring TC was y (Osaka)=1.000x (CDC)+0.032 (n=619, R(2)=1.000). Six Japanese manufacturers had allowable performance for certification. The AK RMP for TC measurement was accurate, precise, and stable for 22 years. Six Japanese manufacturers were certified for 16 years. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. [Quantification of carotenoids of spirilloxanthin series from anoxygenic phototrophic bacteria by substitute reference standard calibration function method].

    PubMed

    Zhao, Chungui; Zhuo, Minquan; Yang, Suping

    2014-02-04

    In this study, we developed a strategy for accurate, rapid and simultaneous quantification of six carotenoids by substitute reference standard. We prepared six carotenoid standards of spirilloxanthin series from Rhodopesudomonnas palustris CQV97 by spectrophotometry, thin layer chromatography and HPLC. The simultaneous quantification method for six carotenoids was established by HPLC using tartrazine and lycopene as substitute reference standards. We established the HPLC fingerprinting of carotenoids of spirilloxanthin series. The quantitative calibration function relationships between two substitute reference standards and six carotenoids were explored. Based on the quantitative calibration function relationships, we quantitatively analyzed carotenoid contents of two samples of CQV97 and YL28 strains. The RSD and recovery of carotenoid contents determined by substitute reference standards method were consistent with quantitative analysis of carotenoid standards method. The substitute reference standards were capable of accurately transmitting the quantitative relationship of tested samples. The method could realize the simultaneous quantification of six carotenoids.

  12. The self-consistent electron pairs method for multiconfiguration reference state functions

    NASA Astrophysics Data System (ADS)

    Werner, Hans-Joachim; Reinsch, Ernst-Albrecht

    1982-03-01

    An efficient direct CI method which includes all singly and doubly substituted configurations with respect to an arbitrary multiconfiguration (MCSCF) reference function is described. The configurations are generated by subsequently applying spin-coupled two-particle annihilation and creation operators to the complete MCSCF function. This considerably reduces the size of the n-electron basis and the computational effort as compared to previous multireference CI treatments, in which the configurations are defined with respect to the individual reference configurations. The formalism of the method is very similar to the closed-shell ''self-consistent electron pairs'' (SCEP) method of Meyer. The vector Hc is obtained in terms of simple matrix operations involving coefficient and integral matrices. A full transformation of the two-electron integrals is not required. Test calculations with large basis sets have been performed for the 3B1 and 1A1 states of CH2 (ΔE = 9.5 kcal/mol) and for the CH2(3B1) +H2→CH3+H reaction barrier (ΔE = 10.7 kcal/mol). As a preliminary test for the accuracy of the results obtained with contracted wave functions of the above type the potential energy and dipole moment functions of the OH X 2Π and A 2Σ+ states have been calculated. For the 2Π state re and ωe deviate by less than 10-3 Å and 1 cm-1, respectively, from the experimental data. For the 2Σ+ state the agreement is somewhat less good, which is probably due to basis set defects. Around the equilibrium distance the calculated dipole moment functions are in very close agreement with those previously obtained from PNO- CEPA functions.

  13. Bayesian methods for uncertainty factor application for derivation of reference values.

    PubMed

    Simon, Ted W; Zhu, Yiliang; Dourson, Michael L; Beck, Nancy B

    2016-10-01

    In 2014, the National Research Council (NRC) published Review of EPA's Integrated Risk Information System (IRIS) Process that considers methods EPA uses for developing toxicity criteria for non-carcinogens. These criteria are the Reference Dose (RfD) for oral exposure and Reference Concentration (RfC) for inhalation exposure. The NRC Review suggested using Bayesian methods for application of uncertainty factors (UFs) to adjust the point of departure dose or concentration to a level considered to be without adverse effects for the human population. The NRC foresaw Bayesian methods would be potentially useful for combining toxicity data from disparate sources-high throughput assays, animal testing, and observational epidemiology. UFs represent five distinct areas for which both adjustment and consideration of uncertainty may be needed. NRC suggested UFs could be represented as Bayesian prior distributions, illustrated the use of a log-normal distribution to represent the composite UF, and combined this distribution with a log-normal distribution representing uncertainty in the point of departure (POD) to reflect the overall uncertainty. Here, we explore these suggestions and present a refinement of the methodology suggested by NRC that considers each individual UF as a distribution. From an examination of 24 evaluations from EPA's IRIS program, when individual UFs were represented using this approach, the geometric mean fold change in the value of the RfD or RfC increased from 3 to over 30, depending on the number of individual UFs used and the sophistication of the assessment. We present example calculations and recommendations for implementing the refined NRC methodology.

  14. Numerical methods for the weakly compressible Generalized Langevin Model in Eulerian reference frame

    SciTech Connect

    Azarnykh, Dmitrii Litvinov, Sergey; Adams, Nikolaus A.

    2016-06-01

    A well established approach for the computation of turbulent flow without resolving all turbulent flow scales is to solve a filtered or averaged set of equations, and to model non-resolved scales by closures derived from transported probability density functions (PDF) for velocity fluctuations. Effective numerical methods for PDF transport employ the equivalence between the Fokker–Planck equation for the PDF and a Generalized Langevin Model (GLM), and compute the PDF by transporting a set of sampling particles by GLM (Pope (1985) [1]). The natural representation of GLM is a system of stochastic differential equations in a Lagrangian reference frame, typically solved by particle methods. A representation in a Eulerian reference frame, however, has the potential to significantly reduce computational effort and to allow for the seamless integration into a Eulerian-frame numerical flow solver. GLM in a Eulerian frame (GLMEF) formally corresponds to the nonlinear fluctuating hydrodynamic equations derived by Nakamura and Yoshimori (2009) [12]. Unlike the more common Landau–Lifshitz Navier–Stokes (LLNS) equations these equations are derived from the underdamped Langevin equation and are not based on a local equilibrium assumption. Similarly to LLNS equations the numerical solution of GLMEF requires special considerations. In this paper we investigate different numerical approaches to solving GLMEF with respect to the correct representation of stochastic properties of the solution. We find that a discretely conservative staggered finite-difference scheme, adapted from a scheme originally proposed for turbulent incompressible flow, in conjunction with a strongly stable (for non-stochastic PDE) Runge–Kutta method performs better for GLMEF than schemes adopted from those proposed previously for the LLNS. We show that equilibrium stochastic fluctuations are correctly reproduced.

  15. Numerical methods for the weakly compressible Generalized Langevin Model in Eulerian reference frame

    NASA Astrophysics Data System (ADS)

    Azarnykh, Dmitrii; Litvinov, Sergey; Adams, Nikolaus A.

    2016-06-01

    A well established approach for the computation of turbulent flow without resolving all turbulent flow scales is to solve a filtered or averaged set of equations, and to model non-resolved scales by closures derived from transported probability density functions (PDF) for velocity fluctuations. Effective numerical methods for PDF transport employ the equivalence between the Fokker-Planck equation for the PDF and a Generalized Langevin Model (GLM), and compute the PDF by transporting a set of sampling particles by GLM (Pope (1985) [1]). The natural representation of GLM is a system of stochastic differential equations in a Lagrangian reference frame, typically solved by particle methods. A representation in a Eulerian reference frame, however, has the potential to significantly reduce computational effort and to allow for the seamless integration into a Eulerian-frame numerical flow solver. GLM in a Eulerian frame (GLMEF) formally corresponds to the nonlinear fluctuating hydrodynamic equations derived by Nakamura and Yoshimori (2009) [12]. Unlike the more common Landau-Lifshitz Navier-Stokes (LLNS) equations these equations are derived from the underdamped Langevin equation and are not based on a local equilibrium assumption. Similarly to LLNS equations the numerical solution of GLMEF requires special considerations. In this paper we investigate different numerical approaches to solving GLMEF with respect to the correct representation of stochastic properties of the solution. We find that a discretely conservative staggered finite-difference scheme, adapted from a scheme originally proposed for turbulent incompressible flow, in conjunction with a strongly stable (for non-stochastic PDE) Runge-Kutta method performs better for GLMEF than schemes adopted from those proposed previously for the LLNS. We show that equilibrium stochastic fluctuations are correctly reproduced.

  16. Selecting the optimal method to calculate daily global reference potential evaporation from CFSR reanalysis data

    NASA Astrophysics Data System (ADS)

    Sperna Weiland, F. C.; Tisseuil, C.; Dürr, H. H.; Vrac, M.; van Beek, L. P. H.

    2011-07-01

    Potential evaporation (PET) is one of the main inputs of hydrological models. Yet, there is limited consensus on which PET equation is most applicable in hydrological climate impact assessments. In this study six different methods to derive global scale reference PET time series from CFSR reanalysis data are compared: Penman-Monteith, Priestley-Taylor and original and modified versions of the Hargreaves and Blaney-Criddle method. The calculated PET time series are (1) evaluated against global monthly Penman-Monteith PET time series calculated from CRU data and (2) tested on their usability for modeling of global discharge cycles. The lowest root mean squared differences and the least significant deviations (95 % significance level) between monthly CFSR derived PET time series and CRU derived PET were obtained for the cell specific modified Blaney-Criddle equation. However, results show that this modified form is likely to be unstable under changing climate conditions and less reliable for the calculation of daily time series. Although often recommended, the Penman-Monteith equation did not outperform the other methods. In arid regions (e.g., Sahara, central Australia, US deserts), the equation resulted in relatively low PET values and, consequently, led to relatively high discharge values for dry basins (e.g., Orange, Murray and Zambezi). Furthermore, the Penman-Monteith equation has a high data demand and the equation is sensitive to input data inaccuracy. Therefore, we preferred the modified form of the Hargreaves equation, which globally gave reference PET values comparable to CRU derived values. Although it is a relative efficient empirical equation, like Blaney-Criddle, the equation considers multiple spatial varying meteorological variables and consequently performs well for different climate conditions. In the modified form of the Hargreaves equation the multiplication factor is uniformly increased from 0.0023 to 0.0031 to overcome the global underestimation

  17. A new reference method for the determination of the total CO2 concentration in biological fluids.

    PubMed

    Dijkhuizen, P; Fongers, T M; Rispens, P; Zijlstra, W G

    1978-06-15

    It appeared that a part of a measuring system recently developed for the determination of the oxygen content of blood (Dijkhuizen, P., Kwant, G. and Zijlstra, W.G. (1976) Clin. Chim. Acta 68, 79), was perfectly suitable for measuring the total CO2 content of blood, plasma or other fluids. CO2-free room air is pumped through an extraction vessel in which all the CO2 of the sample is set free by an acid reagent, and swept by the carrier gas to a titration vessel containing a BaCl2 solution. CO2 is bound as BaCO3 and the ensuing H+ titrated with an NaOH solution. The method was tested by measuring a series of Na2CO3 reference solutions. The values measured by titration amounted to 99.4 +/- 0.8% of the concentration of the reference solutions (range 10--50 mmol 1(-1). The coefficient of variation was 1.8% for 5 mmol 1(-1) solutions and 0.2% for 50 mmol 1(-1) solutions. In measuring a series of 60 blood samples the coefficient of variation as calculated from duplicate determinations was 1%.

  18. Examination of a Method to Determine the Reference Region for Calculating the Specific Binding Ratio in Dopamine Transporter Imaging.

    PubMed

    Watanabe, Ayumi; Inoue, Yusuke; Asano, Yuji; Kikuchi, Kei; Miyatake, Hiroki; Tokushige, Takanobu

    The specific binding ratio (SBR) was first reported by Tossici-Bolt et al. for quantitative indicators for dopamine transporter (DAT) imaging. It is defined as the ratio of the specific binding concentration of the striatum to the non-specific binding concentration of the whole brain other than the striatum. The non-specific binding concentration is calculated based on the region of interest (ROI), which is set 20 mm inside the outer contour, defined by a threshold technique. Tossici-Bolt et al. used a 50% threshold, but sometimes we couldn't define the ROI of non-specific binding concentration (reference region) and calculate SBR appropriately with a 50% threshold. Therefore, we sought a new method for determining the reference region when calculating SBR. We used data from 20 patients who had undergone DAT imaging in our hospital, to calculate the non-specific binding concentration by the following methods, the threshold to define a reference region was fixed at some specific values (the fixing method) and reference region was visually optimized by an examiner at every examination (the visual optimization method). First, we assessed the reference region of each method visually, and afterward, we quantitatively compared SBR calculated based on each method. In the visual assessment, the scores of the fixing method at 30% and visual optimization method were higher than the scores of the fixing method at other values, with or without scatter correction. In the quantitative assessment, the SBR obtained by visual optimization of the reference region, based on consensus of three radiological technologists, was used as a baseline (the standard method). The values of SBR showed good agreement between the standard method and both the fixing method at 30% and the visual optimization method, with or without scatter correction. Therefore, the fixing method at 30% and the visual optimization method were equally suitable for determining the reference region.

  19. Stacking fault energy in FCC plutonium with multiple reference states in the modified embedded atom method

    NASA Astrophysics Data System (ADS)

    Valone, S. M.; Baskes, M. I.; Rudin, S. P.

    2012-03-01

    Basic concepts from the multi-reference state formalism for determining the functions for the modified embedded atom method (MEAM) are adopted to modeling elemental plutonium (Pu). In the case of elemental Pu, the focus is on the background electron density. Here we utilize a portion of the formalism that determines the structure of the background density necessary to capture correct phase ordering between fcc and ideal hcp crystal structures. The critical information comes from cold curves, that is the energy/volume relationships, for these phases. Practically speaking, the energy difference between these two phases determines the stacking fault energy of the material. At the same time, the simple monoclinic phase of elemental Pu also becomes higher in energy at the equilibrium volume of the fcc phase. The new model is based on first-principles electronic structure calculations and captures the basic phase ordering of those calculations.

  20. Comparison of various detection methods for periodontopathic bacteria: can culture be considered the primary reference standard?

    PubMed Central

    Loesche, W J; Lopatin, D E; Stoll, J; van Poperin, N; Hujoel, P P

    1992-01-01

    The development of diagnostic tests for a periodontal infection raises the issue as to what the appropriate reference standard, or "gold standard," should be for the evaluation of a new test. The present research was initiated to compare the ability of several detection methods, i.e., a serial dilution anaerobic culture and/or microscopic procedure, a DNA probe procedure, and immunological reagents using both an enzyme-linked immunosorbent assay and an indirect immunofluorescence assay to detect Treponema denticola, Porphyromonas gingivalis, Bacteroides forsythus, and Actinobacillus actinomycetemcomitans in subgingival plaque samples taken from 204 periodontally diseased tooth sites. The prevalence of the four monitored species varied as a function of both the species and the detection method. Spirochetes were present in 99% of the plaques, whereas A. actinomycetemcomitans was detected at the lowest frequency. The culture method yielded the lowest prevalence values for the three cultivable species. This raised the question as to which results, those obtained by culture or those obtained by the DNA probes and the immunological reagents, were the most reliable. This issue was addressed by looking at the prevalence profile of the monitored organisms, as determined by all the detection methods. If the species was detected by three or four of the detection methods, then it was considered present, whereas if it was absent by three or four of the detection methods, then it was considered absent. This approach showed the DNA probes and immunological reagents to be significantly superior (P less than 0.05) to the culture approach for the detection of P. gingivalis, A. actinomycetemcomitans, and B. forsythus and to be comparable to the microscopic approach in the detection of T. denticola. PMID:1537912

  1. Variability of bioaccessibility results using seventeen different methods on a standard reference material, NIST 2710.

    PubMed

    Koch, Iris; Reimer, Kenneth J; Bakker, Martine I; Basta, Nicholas T; Cave, Mark R; Denys, Sébastien; Dodd, Matt; Hale, Beverly A; Irwin, Rob; Lowney, Yvette W; Moore, Margo M; Paquin, Viviane; Rasmussen, Pat E; Repaso-Subang, Theresa; Stephenson, Gladys L; Siciliano, Steven D; Wragg, Joanna; Zagury, Gerald J

    2013-01-01

    Bioaccessibility is a measurement of a substance's solubility in the human gastro-intestinal system, and is often used in the risk assessment of soils. The present study was designed to determine the variability among laboratories using different methods to measure the bioaccessibility of 24 inorganic contaminants in one standardized soil sample, the standard reference material NIST 2710. Fourteen laboratories used a total of 17 bioaccessibility extraction methods. The variability between methods was assessed by calculating the reproducibility relative standard deviations (RSDs), where reproducibility is the sum of within-laboratory and between-laboratory variability. Whereas within-laboratory repeatability was usually better than (<) 15% for most elements, reproducibility RSDs were much higher, indicating more variability, although for many elements they were comparable to typical uncertainties (e.g., 30% in commercial laboratories). For five trace elements of interest, reproducibility RSDs were: arsenic (As), 22-44%; cadmium (Cd), 11-41%; Cu, 15-30%; lead (Pb), 45-83%; and Zn, 18-56%. Only one method variable, pH, was found to correlate significantly with bioaccessibility for aluminum (Al), Cd, copper (Cu), manganese (Mn), Pb and zinc (Zn) but other method variables could not be examined systematically because of the study design. When bioaccessibility results were directly compared with bioavailability results for As (swine and mouse) and Pb (swine), four methods returned results within uncertainty ranges for both elements: two that were defined as simpler (gastric phase only, limited chemicals) and two were more complex (gastric + intestinal phases, with a mixture of chemicals).

  2. A Design Method of Code Correlation Reference Waveform in GNSS Based on Least-Squares Fitting.

    PubMed

    Xu, Chengtao; Liu, Zhe; Tang, Xiaomei; Wang, Feixue

    2016-07-29

    The multipath effect is one of the main error sources in the Global Satellite Navigation Systems (GNSSs). The code correlation reference waveform (CCRW) technique is an effective multipath mitigation algorithm for the binary phase shift keying (BPSK) signal. However, it encounters the false lock problem in code tracking, when applied to the binary offset carrier (BOC) signals. A least-squares approximation method of the CCRW design scheme is proposed, utilizing the truncated singular value decomposition method. This algorithm was performed for the BPSK signal, BOC(1,1) signal, BOC(2,1) signal, BOC(6,1) and BOC(7,1) signal. The approximation results of CCRWs were presented. Furthermore, the performances of the approximation results are analyzed in terms of the multipath error envelope and the tracking jitter. The results show that the proposed method can realize coherent and non-coherent CCRW discriminators without false lock points. Generally, there is performance degradation in the tracking jitter, if compared to the CCRW discriminator. However, the performance promotions in the multipath error envelope for the BOC(1,1) and BPSK signals makes the discriminator attractive, and it can be applied to high-order BOC signals.

  3. Formulation of probabilistic models of protein structure in atomic detail using the reference ratio method.

    PubMed

    Valentin, Jan B; Andreetta, Christian; Boomsma, Wouter; Bottaro, Sandro; Ferkinghoff-Borg, Jesper; Frellsen, Jes; Mardia, Kanti V; Tian, Pengfei; Hamelryck, Thomas

    2014-02-01

    We propose a method to formulate probabilistic models of protein structure in atomic detail, for a given amino acid sequence, based on Bayesian principles, while retaining a close link to physics. We start from two previously developed probabilistic models of protein structure on a local length scale, which concern the dihedral angles in main chain and side chains, respectively. Conceptually, this constitutes a probabilistic and continuous alternative to the use of discrete fragment and rotamer libraries. The local model is combined with a nonlocal model that involves a small number of energy terms according to a physical force field, and some information on the overall secondary structure content. In this initial study we focus on the formulation of the joint model and the evaluation of the use of an energy vector as a descriptor of a protein's nonlocal structure; hence, we derive the parameters of the nonlocal model from the native structure without loss of generality. The local and nonlocal models are combined using the reference ratio method, which is a well-justified probabilistic construction. For evaluation, we use the resulting joint models to predict the structure of four proteins. The results indicate that the proposed method and the probabilistic models show considerable promise for probabilistic protein structure prediction and related applications. Copyright © 2013 Wiley Periodicals, Inc.

  4. On Statistical Methods for Common Mean and Reference Confidence Intervals in Interlaboratory Comparisons for Temperature

    NASA Astrophysics Data System (ADS)

    Witkovský, Viktor; Wimmer, Gejza; Ďuriš, Stanislav

    2015-08-01

    We consider a problem of constructing the exact and/or approximate coverage intervals for the common mean of several independent distributions. In a metrological context, this problem is closely related to evaluation of the interlaboratory comparison experiments, and in particular, to determination of the reference value (estimate) of a measurand and its uncertainty, or alternatively, to determination of the coverage interval for a measurand at a given level of confidence, based on such comparison data. We present a brief overview of some specific statistical models, methods, and algorithms useful for determination of the common mean and its uncertainty, or alternatively, the proper interval estimator. We illustrate their applicability by a simple simulation study and also by example of interlaboratory comparisons for temperature. In particular, we shall consider methods based on (i) the heteroscedastic common mean fixed effect model, assuming negligible laboratory biases, (ii) the heteroscedastic common mean random effects model with common (unknown) distribution of the laboratory biases, and (iii) the heteroscedastic common mean random effects model with possibly different (known) distributions of the laboratory biases. Finally, we consider a method, recently suggested by Singh et al., for determination of the interval estimator for a common mean based on combining information from independent sources through confidence distributions.

  5. A Design Method of Code Correlation Reference Waveform in GNSS Based on Least-Squares Fitting

    PubMed Central

    Xu, Chengtao; Liu, Zhe; Tang, Xiaomei; Wang, Feixue

    2016-01-01

    The multipath effect is one of the main error sources in the Global Satellite Navigation Systems (GNSSs). The code correlation reference waveform (CCRW) technique is an effective multipath mitigation algorithm for the binary phase shift keying (BPSK) signal. However, it encounters the false lock problem in code tracking, when applied to the binary offset carrier (BOC) signals. A least-squares approximation method of the CCRW design scheme is proposed, utilizing the truncated singular value decomposition method. This algorithm was performed for the BPSK signal, BOC(1,1) signal, BOC(2,1) signal, BOC(6,1) and BOC(7,1) signal. The approximation results of CCRWs were presented. Furthermore, the performances of the approximation results are analyzed in terms of the multipath error envelope and the tracking jitter. The results show that the proposed method can realize coherent and non-coherent CCRW discriminators without false lock points. Generally, there is performance degradation in the tracking jitter, if compared to the CCRW discriminator. However, the performance promotions in the multipath error envelope for the BOC(1,1) and BPSK signals makes the discriminator attractive, and it can be applied to high-order BOC signals. PMID:27483275

  6. Evaluating vehicle inspection/maintenance programs using on-road emissions data. The Atlanta Reference Method.

    PubMed

    DeHart-Davis, Leisha; Corley, Elizabeth; Rodgers, Michael O

    2002-04-01

    On-road remote sensing data is an increasingly popular source of evaluation information for vehicle inspection/maintenance (I/M) programs. This article conducts one such remote sensing data evaluation for the Atlanta, Georgia, I/M program. The reference method involves comparing emissions differences in I/M and non-I/M fleet vehicles with those predicted by a regulatory computer model. Assuming that on-road emissions differences represent observed effectiveness and model-predicted emissions differences represent effectiveness goals, the Atlanta enhanced I/M program appears to be achieving 83% of its targeted emissions reductions. The method compares favorably with other remote sensing evaluation methods in its ability to be applied over time and its relatively small sample size requirement. The chief limitation to the approach is its reliance on a representative non-I/M fleet, which may differ in characteristics for which controls are difficult to locate. Such potential confounding factors include discrepancies in maintenance trends, socioeconomic conditions, and vehicle quality.

  7. Development of a RIA for clonidine and its comparison with the reference methods

    SciTech Connect

    Arndts, D.; Staehle, H.; Foerster, H.J.

    1981-12-01

    A radioimmunoassay for clonidine was optimized by introducing, as a tracer ligand, an iodinized clonidine derivative specifically labeled with more than 500 Ci/mMol. The detection limit of clonidine was 10 pg/ml. The high assay specificity was demonstrated by a double isotope technique. The intraassay coefficient of variance (VK) was less than 4% for any concentration, the interassay VK did not exceed 8.3%. The assay reliability was increased when the plasma samples were diluted 1:5, prior to analysis, in normal human blood plasma, which was also used for the preparation of the calibration samples. In a comparative manner, this assay system was subjected to double-blind accuracy control tests, including all other reference methods so far described for clonidine analysis in blood plasma samples. The RIA technique presented here turned out to be the most sensitive and most reliable method, requiring, moreover, the smallest volumes of blood plasma (0.05 ml). This procedure was appropriate for routine tests, since one technician could perform 500 sample analyses a day. The advantages and disadvantages of each method are discussed.

  8. Using the Contingent Valuation Method To Measure Patron Benefits of Reference Desk Service in an Academic Library.

    ERIC Educational Resources Information Center

    Harless, David W.; Allen, Frank R.

    1999-01-01

    Describes use of the contingent valuation method, a survey technique, to estimate the economic value that patrons attached to reference-desk service in the Virginia Commonwealth University library. Argues that the appropriate measure of patron benefit from reference service includes use value and option value. (Author/LRW)

  9. A method for linking motor vehicle victim and collision data collected by multiple county agencies.

    PubMed

    Papa, Linda; Mendes, Matthew E; Benton, Tom; Issa, R Raymond; Schmalz, Mark S; Bugnacki, Kristine; Garavaglia, Jan C

    2014-01-01

    This study assessed roadside and bedside factors associated with early mortality following motor vehicle trauma. This retrospective cohort study evaluated motor vehicle crashes in Orange County Florida in 2009 that became medical examiner cases. Data from the Department of Highway Safety and Motor Vehicles (DHSMV), emergency medical services (EMS), a level I trauma center, and the medical examiner were integrated for the analysis. The primary outcome measure was early death, defined by death within 48 hours of a motor vehicle trauma. Both traditional and nontraditional predictors of early mortality were assessed. The most significant factors associated with early mortality were as follows: (1) From autopsy: hemothorax (odds ratio [OR] = 8.26, 95% confidence interval [CI]: 1.83-37.3) and liver injury (OR = 4.26, 95% CI: 1.70-15.6); (2) from hospital data: systolic blood pressure (OR = 0.98, 95% CI: 0.96-0.99) and having cardiopulmonary resuscitation (CPR) performed in the emergency department (OR = 13.4, 95% CI: 1.51-118.72); and (3) from DHSMV: involvement of drugs and/or alcohol (OR = 4.27, 95% CI: 1.33-13.6), total fatalities (OR = 6.07, 95% CI: 1.57-23.5), speed of vehicle (OR = 1.06, 95% CI: 1.02-1.09), and number of lanes at the crash scene (OR = 1.58, 95% CI: 1.13-2.20). These results were made possible by integrating 4 distinct data sources. As future research in traffic-related injury moves toward prevention, it will be critical to evaluate new preventative strategies quickly and effectively. A unique number that is both patient and event specific that could be incorporated into each of these databases would make such integration seamless. Successful methods for linking data collected by the multiple agencies involved in motor vehicle collisions will ultimately provide invaluable information for medical personnel, researchers, engineers, planners, and policy makers at the local, state, and national levels to identify safety priorities to reduce crash

  10. Antifungal susceptibility of the aspergillus species by Etest and CLSI reference methods.

    PubMed

    Badiee, Parisa; Alborzi, Abdolvahab; Moeini, Mahsa; Haddadi, Pedram; Farshad, Shohreh; Japoni, Aziz; Ziyaeyan, Maziar

    2012-07-01

    Because resistance to antifungal drugs is seen in patients, susceptibility testing of these drugs aids in choosing the appropriate drug and respective epidemiology. This study has investigated and compared susceptibility patterns of the Aspergillus species isolated from patients by the Clinical and Laboratory Standards Institute (CLSI) reference broth microdilution (MD) assay and Etest method. The minimum inhibitory concentrations (MICs) of various antifungal agents (amphotericin B, ketoconazole, itraconazole, and voriconazole) for 108 Aspergillus species isolated from patients were determined by CLSI M38-A broth MD and Etest. The isolates were obtained from clinical samples that included tissues, sputum, bronchoalveolar lavage, abdominal tap, and cerebrospinal fluid. As revealed by the MD method, 63.9% of the isolates were sensitive to amphotericin B and 36.1% were resistant.Etest revealed that 61.1% were sensitive to amphotericin B and 38.9% were resistant. As for ketoconazole, 108 isolates (100%) were shown to be sensitive through the MD method; while the Etest revealedan 88.9% sensitivity and 11.1% were resistant. All species were susceptible to voriconazole, according to both methods. The measure of agreement (Kappa Index) for these three drugs was satisfactory (≥0.6). According to the MD method, 69.4% of the species were susceptible to itraconazole, whereas 30.6% were not.For this drug, the Etest showed 86.1% susceptible and 13.9% resistant. Voriconazole was the most effective agent against isolates. Using RPMI agar, we found the Etest to be helpful, readily available, and easy to use for determining invitro susceptibilities of Aspergillus species to voriconazole, amphotericin B, ketoconazole, and itraconazole in the region of this study.

  11. Budget- and Priority-Setting Criteria at State Health Agencies in Times of Austerity: A Mixed-Methods Study

    PubMed Central

    Resnick, Beth; Kass, Nancy; Sellers, Katie; Young, Jessica; Bernet, Patrick; Jarris, Paul

    2014-01-01

    Objectives. We examined critical budget and priority criteria for state health agencies to identify likely decision-making factors, pressures, and opportunities in times of austerity. Methods. We have presented findings from a 2-stage, mixed-methods study with state public health leaders regarding public health budget- and priority-setting processes. In stage 1, we conducted hour-long interviews in 2011 with 45 health agency executive and division or bureau leaders from 6 states. Stage 2 was an online survey of 207 executive and division or bureau leaders from all state health agencies (66% response rate). Results. Respondents identified 5 key criteria: whether a program was viewed as “mission critical,” the seriousness of the consequences of not funding the program, financing considerations, external directives and mandates, and the magnitude of the problem the program addressed. Conclusions. We have presented empirical findings on criteria used in state health agency budgetary decision-making. These criteria suggested a focus and interest on core public health and the largest public health problems with the most serious ramifications. PMID:24825212

  12. Achieving comparability with IFCC reference method for the measurement of hemoglobin A1c by use of an improved isotope-dilution mass spectrometry method.

    PubMed

    Liu, Hong; Wong, Lingkai; Yong, Sharon; Liu, Qinde; Lee, Tong Kooi

    2015-10-01

    The development of reference measurement methods for hemoglobin A1c (HbA1c) is important for quality assurance in diabetes management. The IFCC reference method using purified proteins as calibration standards is the recommended accuracy-based reference method for the standardization of HbA1c measurement. We developed a highly precise and accurate liquid chromatography-isotope-dilution tandem mass spectrometry (LC-IDMS/MS) procedure, which can serve as an alternative accuracy-based method for HbA1c measurement. In this method, enzymatic proteolysis was applied to sample preparation, followed by LC-IDMS/MS measurement of hemoglobin A0 (HbA0) and HbA1c, using two "signature" hexapeptides for calibration. The concentrations of the signature hexapeptide calibration solutions were, in turn, determined using a hydrolysis method with HCl, followed by LC-IDMS/MS measurement using amino acid solutions as calibration standards. These solutions were gravimetrically prepared from pure amino acid certified reference materials (CRMs). The developed LC-IDMS/MS method was used in participation in an IFCC ring trial for reference laboratories (RELA 2013 and 2014) for HbA1c, where our results were compared with those using the IFCC reference method. The deviations were found to be 0.4-1.7 mmol mol(-1) [or 0.04-0.16% in National Glygohemoglobin Standardization Program (NGSP) units], revealing good comparability with the IFCC reference method. The relative expanded uncertainty of the LC-IDMS/MS was in the range of 2.6% to 2.8% (1.6% to 2.2% after converting to NGSP units). With excellent method precision, good comparability with the IFCC reference method, and a small measurement uncertainty, the developed LC-IDMS/MS method may be used as an alternative accuracy-based reference method for HbA1c measurement.

  13. Developing patient reference groups within general practice: a mixed-methods study.

    PubMed

    Smiddy, Jane; Reay, Joanne; Peckham, Stephen; Williams, Lorraine; Wilson, Patricia

    2015-03-01

    Clinical commissioning groups (CCGs) are required to demonstrate meaningful patient and public engagement and involvement (PPEI). Recent health service reforms have included financial incentives for general practices to develop patient reference groups (PRGs). To explore the impact of the patient participation direct enhanced service (DES) on development of PRGs, the influence of PRGs on decision making within general practice, and their interface with CCGs. A mixed-methods approach within three case study sites in England. Three case study sites were tracked for 18 months as part of an evaluation of PPEI in commissioning. A sub-study focused on PRGs utilising documentary and web-based analysis; results were mapped against findings of the main study. Evidence highlighted variations in the establishment of PRGs, with the number of active PRGs via practice websites ranging from 27% to 93%. Such groups were given a number of descriptions such as patient reference groups, patient participation groups, and patient forums. Data analysis highlighted that the mode of operation varied between virtual and tangible groups and whether they were GP- or patient-led, such analysis enabled the construction of a typology of PRGs. Evidence reviewed suggested that groups functioned within parameters of the DES with activities limited to practice level. Data analysis highlighted a lack of strategic vision in relation to such groups, particularly their role within an overall patient and PPEI framework). Findings identified diversity in the operationalisation of PRGs. Their development does not appear linked to a strategic vision or overall PPEI framework. Although local pragmatic issues are important to patients, GPs must ensure that PRGs develop strategic direction if health reforms are to be addressed. © British Journal of General Practice 2015.

  14. Design Of A SCRAMJET Nozzle With Streamline Tracing Technique And Reference Temerature Methode

    NASA Astrophysics Data System (ADS)

    Riehmer, J.; Gulhan, A.

    2011-05-01

    This study presents a method to find an optimal shape of a three-dimensional supersonic nozzle for a rectangular scramjet combustion chamber with rounded edges by taking into account the skin friction effects. The geometric and flow constraints are defined within the German DFG GRK 1095/2 project and the designed nozzle will be part of a scramjet demonstrator configuration [1]. The nozzle inlet conditions are mean values of the combustion chamber exit conditions with the assumption of a constant specific heat ratio. To generate the shape of the nozzle a streamline tracing technique is applied to an axis-symmetric flow field calculated by the Method of Characteristics (MOC). Skin friction in relatively high pressure supersonic flow from the combustion chamber is very dominant and cannot be neglected in the design process. Therefore the skin friction is calculated using the Reference Temperature Method (RTM) and used for the determination of the thrust and moment vectors. This allows considering viscous effects without boundary layer calculations. With this approach an optimal truncated ideal nozzle contour which yields the geometric constraints can be derived. For the validation of this method comparative calculations have been carried out with the DLR code TAU on an exemplary axis-symmetric supersonic nozzle for different flow conditions. Results showed a good agreement. Finally for the three-dimensional nozzle the analytical solution for the inviscous and viscous case provided comparable data like TAU simulations. Further simplifications of the approach for an efficient three-dimensional nozzle design will be addressed in the paper.

  15. Methods based on remote sensing data for environmental monitoring to support National and Regional Protection Agencies

    NASA Astrophysics Data System (ADS)

    Cuomo, V.; Lasaponara, R.; Macchiato, F. M.; Simoniello, T.

    2001-05-01

    Remote sensing provides useful data for environmental monitoring nevertheless, efforts are required to test and evaluate methods and techniques to be applied for operational applications. Since 1994, in the context of several projects founded by the Italian Environment Protection Agency (ANPA) and Environmental Department of Basilicata Region, we have experienced the use of remote sensing for environmental monitoring in operative contexts. Particularly, we have developed and tested methodologies based on the integration of remote sensed data aimed at: estimations of space/temporal dynamics of surface parameters (such as temperature and vegetation indexes), forest fire detection and danger estimation, risk assessment, change detection, desertification, alpine ice monitoring, etc. Some examples are briefly summarized below. The action C of Timoran projects was devoted to forest fire monitoring. We devised a dynamic short time fire forecasting based on the integration of remote sensing and GIS. A daily fire susceptibility assessment was performed, from NOAA-AVHRR exploiting the cross analysis of the temporal evolution of NDVI and the middle-infrared channel. Four danger classes have been obtained (low, moderate, high and very high). We also estimated the expected fire severity combining and integrating different danger variables, such as: (1) fire susceptibility (water stress) performed using satellite AVHRR data, (2) fuel type, (3) incidence of topography, (4) wind forecast, obtained from meteorological models. Potential and limitations of AVHRR for fire detection were evaluated in the Italian ecosystems. At present we are working on evaluating the effectiveness of Landsat-TM imagery for mapping burned area in heterogeneous regions, characterized by different cover types, rough topography and complex ecosystems. In the context of "Devising of environmental indicators based on remote sensing data" project, funded by ANPA, we investigated on an AVHRR time series from

  16. The effects of user factors and symbol referents on public symbol design using the stereotype production method.

    PubMed

    Ng, Annie W Y; Siu, Kin Wai Michael; Chan, Chetwyn C H

    2012-01-01

    This study investigated the influence of user factors and symbol referents on public symbol design among older people, using the stereotype production method for collecting user ideas during the symbol design process. Thirty-one older adults were asked to draw images based on 28 public symbol referents and to indicate their familiarity with and ease with which they visualised each referent. Differences were found between the pictorial solutions generated by males and females. However, symbol design was not influenced by participants' education level, vividness of visual imagery, object imagery preference or spatial imagery preference. Both familiar and unfamiliar referents were illustrated pictorially without much difficulty by users. The more visual the referent, the less difficulty the users had in illustrating it. The findings of this study should aid the optimisation of the stereotype production method for user-involved symbol design. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  17. Certified DNA Reference Materials to Compare HER2 Gene Amplification Measurements Using Next-Generation Sequencing Methods.

    PubMed

    Lih, Chih-Jian; Si, Han; Das, Biswajit; Harrington, Robin D; Harper, Kneshay N; Sims, David J; McGregor, Paul M; Camalier, Corinne E; Kayserian, Andrew Y; Williams, P Mickey; He, Hua-Jun; Almeida, Jamie L; Lund, Steve P; Choquette, Steve; Cole, Kenneth D

    2016-09-01

    The National Institute of Standards and Technology (NIST) Standard Reference Materials 2373 is a set of genomic DNA samples prepared from five breast cancer cell lines with certified values for the ratio of the HER2 gene copy number to the copy numbers of reference genes determined by real-time quantitative PCR and digital PCR. Targeted-amplicon, whole-exome, and whole-genome sequencing measurements were used with the reference material to compare the performance of both the laboratory steps and the bioinformatic approaches of the different methods using a range of amplification ratios. Although good reproducibility was observed in each next-generation sequencing method, slightly different HER2 copy numbers associated with platform-specific biases were obtained. This study clearly demonstrates the value of Standard Reference Materials 2373 as reference material and as a calibrator for evaluating assay performance as well as for increasing confidence in reporting HER2 amplification for clinical applications.

  18. Development of a new certified reference material of diosgenin using mass balance approach and Coulometric titration method.

    PubMed

    Gong, Ningbo; Zhang, Baoxi; Hu, Fan; Du, Hui; Du, Guanhua; Gao, Zhaolin; Lu, Yang

    2014-12-01

    Certified reference materials (CRMs) can be used as a valuable tool to validate the trueness of measurement methods and to establish metrological traceability of analytical results. Diosgenin has been selected as a candidate reference material. Characterization of the material relied on two different methods, mass balance method and Coulometric titration method (CT). The certified value of diosgenin CRM is 99.80% with an expanded uncertainty of 0.37% (k=2). The new CRM of diosgenin can be used to validate analytical methods, improve the accuracy of measurement data and control the quality of diosgenin in relevant pharmaceutical formulations.

  19. A Novel Method for Estimating Myocardial Strain: Assessment of Deformation Tracking Against Reference Magnetic Resonance Methods in Healthy Volunteers

    PubMed Central

    Mangion, Kenneth; Gao, Hao; McComb, Christie; Carrick, David; Clerfond, Guillaume; Zhong, Xiaodong; Luo, Xiaoyu; Haig, Caroline E.; Berry, Colin

    2016-01-01

    We developed a novel method for tracking myocardial deformation using cardiac magnetic resonance (CMR) cine imaging. We hypothesised that circumferential strain using deformation-tracking has comparable diagnostic performance to a validated method (Displacement Encoding with Stimulated Echoes- DENSE) and potentially diagnostically superior to an established cine-strain method (feature-tracking). 81 healthy adults (44.6 ± 17.7 years old, 47% male), without any history of cardiovascular disease, underwent CMR at 1.5 T including cine, DENSE, and late gadolinium enhancement in subjects >45 years. Acquisitions were divided into 6 segments, and global and segmental peak circumferential strain were derived and analysed by age and sex. Peak circumferential strain differed between the 3 groups (DENSE: −19.4 ± 4.8%; deformation-tracking: −16.8 ± 2.4%; feature-tracking: −28.7 ± 4.8%) (ANOVA with Tukey post-hoc, F-value 279.93, p < 0.01). DENSE and deformation-tracking had better reproducibility than feature-tracking. Intra-class correlation co-efficient was >0.90. Larger magnitudes of strain were detected in women using deformation-tracking and DENSE, but not feature-tracking. Compared with a reference method (DENSE), deformation-tracking using cine imaging has similar diagnostic performance for circumferential strain assessment in healthy individuals. Deformation-tracking could potentially obviate the need for bespoke strain sequences, reducing scanning time and is more reproducible than feature-tracking. PMID:27941903

  20. Budget- and priority-setting criteria at state health agencies in times of austerity: a mixed-methods study.

    PubMed

    Leider, Jonathon P; Resnick, Beth; Kass, Nancy; Sellers, Katie; Young, Jessica; Bernet, Patrick; Jarris, Paul

    2014-06-01

    We examined critical budget and priority criteria for state health agencies to identify likely decision-making factors, pressures, and opportunities in times of austerity. We have presented findings from a 2-stage, mixed-methods study with state public health leaders regarding public health budget- and priority-setting processes. In stage 1, we conducted hour-long interviews in 2011 with 45 health agency executive and division or bureau leaders from 6 states. Stage 2 was an online survey of 207 executive and division or bureau leaders from all state health agencies (66% response rate). Respondents identified 5 key criteria: whether a program was viewed as "mission critical," the seriousness of the consequences of not funding the program, financing considerations, external directives and mandates, and the magnitude of the problem the program addressed. We have presented empirical findings on criteria used in state health agency budgetary decision-making. These criteria suggested a focus and interest on core public health and the largest public health problems with the most serious ramifications.

  1. ID-SERS Based Reference Method for Quantification of Large Biomolecules on a Single Chip

    SciTech Connect

    Yaghobian, Fatemeh; Stosch, Rainer; Henrion, Andre; Guettler, Bernd

    2010-08-06

    Accuracy and precision of quantitative SERS results have been significantly increased by applying a method based on the so-called isotope-dilution (ID) principle. In this ID-SERS approach, an isotopically labeled analogue of the target molecule (isotopologue) is spiked to the sample at a known concentration. Due to the slight difference in their molar masses, some Raman bands of the heavier isotopologue are red-shifted with respect to the same signals resulting from the unlabelled compound. As a result, spectra evaluation is reduced to the determination of intensity ratios rather than absolute intensities, and the unknown quantity of the analyte can be calculated from the known quantity of the standard. This procedure is of particular interest in the development of highly accurate reference procedures for metrology in chemistry. Because the sample is spiked prior to any further treatment, potential loss of material or matrix effects would equally affect both isotopologues, without influencing the final result. The method has been successfully applied for quantifying small diagnostic marker molecules like creatinine at their relevant serum concentration levels using silver colloids as SERS substrates. Now, the ID-SERS approach has been realized as a 'one-chip' approach using 'Bio-chips' made of intrinsically grown spherical silver nanoparticles with gaps less than 10 nm in between (Fig. 1). In addition, the scope of the method has been extended to larger biomolecules like peptides which will be shown using the example of the human growth-hormone (hGH) peptide T12 at physiologically relevant serum concentration levels (Fig. 2). Further developments towards the quantification of full proteins will also be reported.

  2. ID-SERS Based Reference Method for Quantification of Large Biomolecules on a Single Chip

    NASA Astrophysics Data System (ADS)

    Yaghobian, Fatemeh; Stosch, Rainer; Henrion, André; Güttler, Bernd

    2010-08-01

    Accuracy and precision of quantitative SERS results have been significantly increased by applying a method based on the so-called isotope-dilution (ID) principle. In this ID-SERS approach, an isotopically labeled analogue of the target molecule (isotopologue) is spiked to the sample at a known concentration. Due to the slight difference in their molar masses, some Raman bands of the heavier isotopologue are red-shifted with respect to the same signals resulting from the unlabelled compound. As a result, spectra evaluation is reduced to the determination of intensity ratios rather than absolute intensities, and the unknown quantity of the analyte can be calculated from the known quantity of the standard. This procedure is of particular interest in the development of highly accurate reference procedures for metrology in chemistry. Because the sample is spiked prior to any further treatment, potential loss of material or matrix effects would equally affect both isotopologues, without influencing the final result. The method has been successfully applied for quantifying small diagnostic marker molecules like creatinine at their relevant serum concentration levels using silver colloids as SERS substrates. Now, the ID-SERS approach has been realized as a "one-chip" approach using "Bio-chips" made of intrinsically grown spherical silver nanoparticles with gaps less than 10 nm in between (Fig. 1). In addition, the scope of the method has been extended to larger biomolecules like peptides which will be shown using the example of the human growth-hormone (hGH) peptide T12 at physiologically relevant serum concentration levels (Fig. 2). Further developments towards the quantification of full proteins will also be reported.

  3. A reference-free method for brightness compensation and contrast enhancement of micrographs of serial sections.

    PubMed

    Chang, Shi-Jie; Li, Shuo; Andreasen, Arne; Sha, Xian-Zheng; Zhai, Xiao-Yue

    2015-01-01

    Three-dimensional (3D) reconstruction of an organ or tissue from a stack of histologic serial sections provides valuable morphological information. The procedure includes section preparation of the organ or tissue, micrographs acquisition, image registration, 3D reconstruction, and visualization. However, the brightness and contrast through the image stack may not be consistent due to imperfections in the staining procedure, which may cause difficulties in micro-structure identification using virtual sections, region segmentation, automatic target tracing, etc. In the present study, a reference-free method, Sequential Histogram Fitting Algorithm (SHFA), is therefore developed for adjusting the severe and irregular variance of brightness and contrast within the image stack. To apply the SHFA, the gray value histograms of individual images are first calculated over the entire image stack and a set of landmark gray values are chosen. Then the histograms are transformed so that there are no abrupt changes in progressing through the stack. Finally, the pixel gray values of the original images are transformed into the desired ones based on the relationship between the original and the transformed histograms. The SHFA is tested on an image stacks from mouse kidney sections stained with toluidine blue, and captured by a slide scanner. As results, the images through the entire stack reveal homogenous brightness and consistent contrast. In addition, subtle color differences in the tissue are well preserved so that the morphological details can be recognized, even in virtual sections. In conclusion, compared with the existing histogram-based methods, the present study provides a practical method suitable for compensating brightness, and improving contrast of images derived from a large number of serial sections of biological organ.

  4. Transmit-reference methods in software defined radio platforms for communication in harsh propagation environments and systems thereof

    DOEpatents

    Dowla, Farid U; Nekoogar, Faranak

    2015-03-03

    A method for adaptive Radio Frequency (RF) jamming according to one embodiment includes dynamically monitoring a RF spectrum; detecting any undesired signals in real time from the RF spectrum; and sending a directional countermeasure signal to jam the undesired signals. A method for adaptive Radio Frequency (RF) communications according to another embodiment includes transmitting a data pulse in a RF spectrum; and transmitting a reference pulse separated by a predetermined period of time from the data pulse; wherein the data pulse is modulated with data, wherein the reference pulse is unmodulated. A method for adaptive Radio Frequency (RF) communications according to yet another embodiment includes receiving a data pulse in a RF spectrum; and receiving a reference pulse separated in time from the data pulse, wherein the data pulse is modulated with data, wherein the reference pulse is unmodulated; and demodulating the pulses.

  5. Transmit-reference methods in software defined radio platforms for communication in harsh propagation environments and systems thereof

    DOEpatents

    Dowla, Farid; Nekoogar, Faranak

    2017-01-03

    A method for adaptive Radio Frequency (RF) jamming according to one embodiment includes dynamically monitoring a RF spectrum; detecting any undesired signals in real time from the RF spectrum; and sending a directional countermeasure signal to jam the undesired signals. A method for adaptive Radio Frequency (RF) communications according to another embodiment includes transmitting a data pulse in a RF spectrum; and transmitting a reference pulse separated by a predetermined period of time from the data pulse; wherein the data pulse is modulated with data, wherein the reference pulse is unmodulated. A method for adaptive Radio Frequency (RF) communications according to yet another embodiment includes receiving a data pulse in a RF spectrum; and receiving a reference pulse separated in time from the data pulse, wherein the data pulse is modulated with data, wherein the reference pulse is unmodulated; and demodulating the pulses.

  6. Development of internal forest soil reference samples and testing of digestion methods

    Treesearch

    J.E. Hislop; J.W. Hornbeck; S.W. Bailey; R.A. Hallett

    1998-01-01

    Our research requires determinations of total elemental concentrations of forest soils. The lack of certified forest soil reference materials led us to develop internal reference samples. Samples were collected from three soil horizons (Oa, B, and C) at three locations having forested, acidic soils similar to those we commonly analyze. A shatterbox was used to...

  7. A noble method on no-reference video quality assessment using block modes and quantization parameters of H.264/AVC

    NASA Astrophysics Data System (ADS)

    Park, Inkyung; Na, Taeyoung; Kim, Munchurl

    2011-01-01

    Video quality assessment is an important tool of guaranteeing video services in a required level of quality. Although subjective quality assessment is more reliable due to the reflection of Human Visual System (HVS) than objective quality assessment, it is a time-consuming and very expensive approach, and is not appropriate for real-time applications. Therefore, much research has been made for objective video quality assessment instead of subjective video quality assessment. Among three kinds of objective assessment approaches which are full-reference, reduced-reference and no-reference methods, no-reference method has drawn much attention because it does not require any reference. The encoding parameters are good features to use for no-reference model because the encoded bitstreams carry plenty of information about the video contents and it is easy to extract some coding parameters to assess visual quality. In this paper, we propose a no-reference quality metric using two kinds of coding parameters in H.264/AVC: quantization and block mode parameters. These parameters are extracted and computed from H.264/AVC bitstreams, without relying on pixel domain processing. We design a linear quality metric composed of these two parameters. The weight values of the parameters are estimated using linear regression with the results of subjective quality assessment which are obtained based on the DSIS (Double Stimulus Impairment Scale) method of ITU-R BT.500-11.

  8. Multi-Component Molecular-Level Body Composition Reference Methods: Evolving Concepts and Future Directions

    PubMed Central

    Heymsfield, Steven B.; Ebbeling, Cara B.; Zheng, Jolene; Pietrobelli, Angelo; Strauss, Boyd J.; Silva, Analiza M.; Ludwig, David S.

    2015-01-01

    Excess adiposity is the main phenotypic feature that defines human obesity and that plays a pathophysiological role in most chronic diseases. Measuring the amount of fat mass present is thus a central aspect of studying obesity at the individual and population levels. Nevertheless, a consensus is lacking among investigators on a single accepted “reference” approach for quantifying fat mass in vivo. While the research community generally relies on the multicomponent body-volume class of “reference” models for quantifying fat mass, no definable guide discerns among different applied equations for partitioning the four (fat, water, protein, and mineral mass) or more quantified components, standardizes “adjustment” or measurement system approaches for model-required labeled water dilution volumes and bone mineral mass estimates, or firmly establishes the body temperature at which model physical properties are assumed. The resulting differing reference strategies for quantifying body composition in vivo leads to small but under some circumstances important differences in the amount of measured body fat. Recent technological advances highlight opportunities to expand model applications to new subject groups and measured components such as total body protein. The current report reviews the historical evolution of multicomponent body volume-based methods in the context of prevailing uncertainties and future potential. PMID:25645009

  9. A gene-based association method for mapping traits using reference transcriptome data

    PubMed Central

    Gamazon, Eric R.; Wheeler, Heather E.; Shah, Kaanan P.; Mozaffari, Sahar V.; Aquino-Michaels, Keston; Carroll, Robert J.; Eyler, Anne E.; Denny, Joshua C.; Nicolae, Dan L.; Cox, Nancy J.; Kyung Im, Hae

    2015-01-01

    Genome-wide association studies (GWAS) have identified thousands of variants robustly associated with complex traits. However, the biological mechanisms underlying these associations are, in general, not well understood. We propose a gene-based association method called PrediXcan that directly tests the molecular mechanisms through which genetic variation affects phenotype. The approach estimates the component of gene expression determined by an individual’s genetic profile and correlates the “imputed” gene expression with the phenotype under investigation to identify genes involved in the etiology of the phenotype. The genetically regulated gene expression is estimated using whole-genome tissue-dependent prediction models trained with reference transcriptome datasets. PrediXcan enjoys the benefits of gene-based approaches such as reduced multiple testing burden and a principled approach to the design of follow-up experiments. Our results demonstrate that PrediXcan can detect known and novel genes associated with disease traits and provide insights into the mechanism of these associations. PMID:26258848

  10. The Kjeldahl method as a primary reference procedure for total protein in certified reference materials used in clinical chemistry. I. A review of Kjeldahl methods adopted by laboratory medicine.

    PubMed

    Chromý, Vratislav; Vinklárková, Bára; Šprongl, Luděk; Bittová, Miroslava

    2015-01-01

    We found previously that albumin-calibrated total protein in certified reference materials causes unacceptable positive bias in analysis of human sera. The simplest way to cure this defect is the use of human-based serum/plasma standards calibrated by the Kjeldahl method. Such standards, commutative with serum samples, will compensate for bias caused by lipids and bilirubin in most human sera. To find a suitable primary reference procedure for total protein in reference materials, we reviewed Kjeldahl methods adopted by laboratory medicine. We found two methods recommended for total protein in human samples: an indirect analysis based on total Kjeldahl nitrogen corrected for its nonprotein nitrogen and a direct analysis made on isolated protein precipitates. The methods found will be assessed in a subsequent article.

  11. Comparison of two analog-based downscaling methods for regional reference evapotranspiration forecasts

    NASA Astrophysics Data System (ADS)

    Tian, Di; Martinez, Christopher J.

    2012-12-01

    SummaryThe objective of this study was to compare the performance of natural analog (NA) and constructed analog (CA) methods to produce both probabilistic and deterministic downscaled daily reference evapotranspiration (ETo) forecasts in the southeastern United States. The 1-15 day, 15-member ETo forecasts were produced from 1979 to 2009 using the Penman-Monteith equation and a forecast analog approach with a combination of the Global Forecast System (GFS) reforecasts and NCEP-DOE Reanalysis 2 climatology, and were downscaled using the North American Regional Reanalysis (NARR). The Pearson correlation coefficient (R), mean squared error skill score (MSESS), and Bias were used to evaluate the skill of downscaled deterministic forecasts. The Linear Error in Probability Space (LEPS) skill score, Brier Skill Score (BSS), relative operating characteristic, and reliability diagrams were used to evaluate the skill of downscaled probabilistic forecasts. Overall, CA showed slightly higher skill than NA in terms of the metrics for deterministic forecasts, while for probabilistic forecasts NA showed higher skill than CA regarding the BSS in five categories (terciles, and 10th and 90th percentiles) and lower skill than CA regarding the LEPS skill score. Both CA and NA produced skillful deterministic results in the first 3 lead days, while the skill was higher for CA than for NA. Probabilistic NA forecasts exhibited higher resolution and reliability than CA, likely due to a larger ensemble size. Forecasts by both methods showed the lowest skill in the Florida peninsula and in mountainous areas, likely due to the fact that these features were not well-resolved in the model forecast.

  12. EPA's Reference and Equivalent Supporting NAAQS Implementation through Methods Research Program: Research, Development, and Analysis

    EPA Science Inventory

    . To assess the ambient concentration levels of the six criteria air pollutants regulated by National Ambient Air Quality Standards (NAAQS), the U.S. Environmental Protection Agency (EPA) developed a systematic framework of: (a) field measurements of ambient air pollutant levels ...

  13. EPA's Reference and Equivalent Supporting NAAQS Implementation through Methods Research Program: Research, Development, and Analysis

    EPA Science Inventory

    . To assess the ambient concentration levels of the six criteria air pollutants regulated by National Ambient Air Quality Standards (NAAQS), the U.S. Environmental Protection Agency (EPA) developed a systematic framework of: (a) field measurements of ambient air pollutant levels ...

  14. Evaluation of a youth agency's supervision practices: A mixed-method approach.

    PubMed

    Gosselin, Julie; Valiquette-Tessier, Sophie-Claire; Vandette, Marie-Pier; Romano, Elisa

    2015-10-01

    This research presents the findings from an evaluation and organizational development initiative that was requested by a Canadian youth agency working in a large urban setting. A team of four researchers affiliated with the Center for Research on Educational and Community Services (CRECS) at the University of Ottawa conducted the evaluation. The purpose of the evaluation was to identify the supervision needs and challenges of coordinators and front line staff, assess the efficiency of the current supervision practices, and evaluate the supervisors' and supervisees' satisfaction with these current practices. A literature review was performed to help provide a clear definition of 'supervision' and the different professional roles it encompasses. Additionally, research evidence pertaining both to what contributes to supervision efficacy and supervisor competency was reviewed to distill the most robust findings in the existing literature. The lines of evidence consisted of a document and file review, an online employee survey, group discussions (i.e. focus groups), and interviews with key informants. The results of the evaluation helped the research team formulate recommendations to the agency for the development of enhanced supervision practices across its various service areas.

  15. Correlative multiple porosimetries for reservoir sandstones with adoption of a new reference-sample-guided computed-tomographic method

    PubMed Central

    Jin, Jae Hwa; Kim, Junho; Lee, Jeong-Yil; Oh, Young Min

    2016-01-01

    One of the main interests in petroleum geology and reservoir engineering is to quantify the porosity of reservoir beds as accurately as possible. A variety of direct measurements, including methods of mercury intrusion, helium injection and petrographic image analysis, have been developed; however, their application frequently yields equivocal results because these methods are different in theoretical bases, means of measurement, and causes of measurement errors. Here, we present a set of porosities measured in Berea Sandstone samples by the multiple methods, in particular with adoption of a new method using computed tomography and reference samples. The multiple porosimetric data show a marked correlativeness among different methods, suggesting that these methods are compatible with each other. The new method of reference-sample-guided computed tomography is more effective than the previous methods when the accompanied merits such as experimental conveniences are taken into account. PMID:27445105

  16. A method to remove odd harmonic interferences in square wave reference digital lock-in amplifier.

    PubMed

    Li, Gang; Zhang, Shengzhao; Zhou, Mei; Li, Yongcheng; Lin, Ling

    2013-02-01

    Digital lock-in amplifier using square wave reference is much easier to be implemented compared to digital lock-in amplifier using sinusoidal wave reference. However, because of the odd harmonics containing in the square wave reference, the interferences at the odd harmonics of the reference cannot be removed with conventional algorithm. A new square wave digital lock-in algorithm is presented in this paper. It cannot only be capable of removing the interferences of the odd harmonics in the signal, but also can detect the amplitudes and the phases of the interferences. The real and imaginary parts of the frequency component of interest and those of the odd harmonic interferences are calculated simultaneously. The results of simulation experiments show the feasibility of the proposed algorithm. The algorithm is computationally efficient and thus suitable for weak signal detection implemented in the general microprocessor.

  17. Methods for Derivation of Inhalation Reference Concentrations and Application of Inhalation Dosimetry

    EPA Pesticide Factsheets

    EPA's methodology for estimation of inhalation reference concentrations (RfCs) as benchmark estimates of the quantitative dose-response assessment of chronic noncancer toxicity for individual inhaled chemicals.

  18. An alternative method for the certification of the sulfur mass fraction in coal Standard Reference Materials.

    PubMed

    Winchester, M R; Kelly, W R; Mann, J L; Guthrie, W F; MacDonald, B S; Turk, G C

    2001-06-01

    The S mass fractions of coal SRMs 2682b, 2684b, and 2685b are certified by direct comparison with coal SRMs 2682a, 2684a, and 2685a, respectively, using high-temperature combustion analysis with infrared (IR) absorption detection. The S mass fractions of the "a" materials used for calibration were previously determined by means of isotope-dilution thermal-ionization mass spectrometry (ID-TIMS). Therefore, the comparisons performed with the combustion-IR absorption method establish direct traceability links to accurate and precise ID-TIMS measurements. The expanded uncertainties associated with the certified S mass fractions are of approximately the same magnitude as would be expected for the ID-TIMS methodology. An important aspect of these certifications is that each "b" material is essentially identical with the corresponding "a" material, because both were produced from the same bulk, homogenized coal. As a test of the efficacy of the new certification approach when calibrant and unknown are not identical, the S mass fraction of coal SRM 2683b has been determined by direct comparison to coal SRM 2683a. These two coals, which have both previously been analyzed with ID-TIMS, are different in terms of S content and other properties. Whereas the S mass fraction for SRM 2683b determined with the new methodology agrees statistically with the ID-TIMS value, there is reason for caution in such cases. In addition to the usefulness of the alternative approach for certification activities within NIST, this approach might also be an excellent way of establishing NIST traceability during the value assignment process for reference materials not issued by NIST. Further research is needed, however, to understand better the scope of applicability.

  19. Digital analysis of the orbit using the non-referring method

    PubMed Central

    Dąbek, Józefa; Piechota, Mieczysław; Bajor, Grzegorz; Aniszewski, Łukasz; Markowski, Jarosław

    2014-01-01

    Introduction Anthropological analysis of the orbits using classic anthropometric instruments based on width and height measurements as well as orbital index allows for classification of orbits in terms of their shape, yet it has poor clinical application. Nowadays computer graphics enables a precise research technique implementing the latest achievements in digital technology and data recording. The aim of the study was to compare in let parameters of left and right orbits in male and female skulls by means of digital analysis techniques. Material and methods The analysis was carried out on 184 early medieval well-preserved skulls. The examined crania were fixed into Molisson's craniost at in the author's own modification. They were directed in space towards the Frankfurt plane and photographed in a frontal norm. Parameters describing the plane structure of the orbits were obtained through computer analysis, integrating raster and vector graphics of mathematical recordings of craniofacial structures. Results The research demonstrated some differences between male and female skulls. Parameters of right orbit like area, circumference, radius, excavation, circularity deviation and functional were statistically significant higher values in male skull. The following parameters of left orbit: area, circumference, reference circle radius, parameter describing height between two point (mf-ek), maximal width, maximal excavation in relation to median and mean, circularity deviation and functional were statistically significant higher parameter in the male group. Conclusions Orbit shape variability, and especially variability of the orbit in let, are highly important features for anthropologists and maxillofacial surgeons, hence the usefulness of the in let orbit shape digital analysis. PMID:24701232

  20. A NEW APPROACH FOR CULTURING LEMNA MINOR (DUCKWEED) AND STANDARDIZED METHOD FOR USING ATRAZINE AS A REFERENCE TOXICANT

    EPA Science Inventory

    Lemna minor (Duckweed) is commonly used in aquatic toxicity investigations. Methods for culturing and testing with reference toxicants, such as atrazine, are somewhat variable among researchers. Our goal was to develop standardized methods of culturing and testing for use with L....

  1. Reference and Equivalent Methods Used to Measure National Ambient Air Quality Standards (NAAQS) Criteria Air Pollutants - Volume I

    EPA Science Inventory

    There are a number of Federal Reference Method (FRM) and Federal Equivalent Method (FEM) systems used to monitor the six criteria air pollutants (Lead [Pb], Carbon Monoxide [CO], Sulfur Dioxide [SO2], Nitrogen Dioxide [NO2], Ozone [O3], Particulate Matter [PM]) to determine if an...

  2. Reference and Equivalent Methods Used to Measure National Ambient Air Quality Standards (NAAQS) Criteria Air Pollutants - Volume I

    EPA Science Inventory

    There are a number of Federal Reference Method (FRM) and Federal Equivalent Method (FEM) systems used to monitor the six criteria air pollutants (Lead [Pb], Carbon Monoxide [CO], Sulfur Dioxide [SO2], Nitrogen Dioxide [NO2], Ozone [O3], Particulate Matter [PM]) to determine if an...

  3. A NEW APPROACH FOR CULTURING LEMNA MINOR (DUCKWEED) AND STANDARDIZED METHOD FOR USING ATRAZINE AS A REFERENCE TOXICANT

    EPA Science Inventory

    Lemna minor (Duckweed) is commonly used in aquatic toxicity investigations. Methods for culturing and testing with reference toxicants, such as atrazine, are somewhat variable among researchers. Our goal was to develop standardized methods of culturing and testing for use with L....

  4. Combining GPS and Terrestrial Methods In VLBI Antenna's Reference Point Determination

    NASA Astrophysics Data System (ADS)

    Sarti, P.; Vittuari, L.; Tomasi, P.

    Surveying the reference point of VLBI radiotelescopes within a local ground control network is, nowadays, a very important task. Reference point can be determined using a molteplicity of approaches. We have choosen and tested a purely theoretical ap- proach, writing two routines for best-fitting 3-D surfaces computation. Surveying the antenna structure as it moves in azimuth and elevation permits the determination of a set of points' positions that are used to determine best-fit spheres and planes whose intersections relates to VLBI antenna axes, i.e.: to the reference point. Our opera- tive dataset has been created during a 14 days campaign performed in June 2001 at Medicina (Bologna-Italy) observatory using both Kinematic GPS and two total sta- tions. GPS data have been analysed using both commercial (GeoGenius 2000 and Geotracer V2.29) and scientific software (GIPSY V.2.6.1). We will present the es- timated reference point's coordinates for the VLBI radiotelescope within ITRF2000 and a local reference frame obtained using KGPS and classical geodesy.

  5. 41 CFR 302-7.16 - Must I use the methods selected by my agency for transportation and temporary storage of my HHG...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... BOOKS, PAPERS, AND EQUIPMENT, (PBP&E) AND BAGGAGE ALLOWANCE General Rules § 302-7.16 Must I use the methods selected by my agency for transportation and temporary storage of my HHG and PBP&E? No, you do not... selected by my agency for transportation and temporary storage of my HHG and PBP&E? 302-7.16 Section...

  6. 41 CFR 302-7.16 - Must I use the methods selected by my agency for transportation and temporary storage of my HHG...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... BOOKS, PAPERS, AND EQUIPMENT (PBP&E) General Rules § 302-7.16 Must I use the methods selected by my agency for transportation and temporary storage of my HHG and PBP&E? No, you do not have to use the... selected by my agency for transportation and temporary storage of my HHG and PBP&E? 302-7.16 Section...

  7. 41 CFR 302-7.16 - Must I use the methods selected by my agency for transportation and temporary storage of my HHG...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... BOOKS, PAPERS, AND EQUIPMENT (PBP&E) General Rules § 302-7.16 Must I use the methods selected by my agency for transportation and temporary storage of my HHG and PBP&E? No, you do not have to use the... selected by my agency for transportation and temporary storage of my HHG and PBP&E? 302-7.16 Section...

  8. The list of prohibited substances and methods in sport: structure and review process by the world anti-doping agency.

    PubMed

    Mazzoni, Irene; Barroso, Osquel; Rabin, Olivier

    2011-11-01

    The List of Prohibited Substances and Methods (the List) is the International Standard that determines what is prohibited in sport in- and out-of-competition. The official text of the List is produced by the World Anti-Doping Agency (WADA), the international independent organization responsible for promoting, coordinating and monitoring the fight against doping in sport. The drafting of the annual List is a highly interactive and consultative process involving scientific and medical experts in anti-doping, sport federations and governments. In this article, the elements that compose the List as well as the process behind its annual revision and update are presented.

  9. De novo clustering methods outperform reference-based methods for assigning 16S rRNA gene sequences to operational taxonomic units.

    PubMed

    Westcott, Sarah L; Schloss, Patrick D

    2015-01-01

    Background. 16S rRNA gene sequences are routinely assigned to operational taxonomic units (OTUs) that are then used to analyze complex microbial communities. A number of methods have been employed to carry out the assignment of 16S rRNA gene sequences to OTUs leading to confusion over which method is optimal. A recent study suggested that a clustering method should be selected based on its ability to generate stable OTU assignments that do not change as additional sequences are added to the dataset. In contrast, we contend that the quality of the OTU assignments, the ability of the method to properly represent the distances between the sequences, is more important. Methods. Our analysis implemented six de novo clustering algorithms including the single linkage, complete linkage, average linkage, abundance-based greedy clustering, distance-based greedy clustering, and Swarm and the open and closed-reference methods. Using two previously published datasets we used the Matthew's Correlation Coefficient (MCC) to assess the stability and quality of OTU assignments. Results. The stability of OTU assignments did not reflect the quality of the assignments. Depending on the dataset being analyzed, the average linkage and the distance and abundance-based greedy clustering methods generated OTUs that were more likely to represent the actual distances between sequences than the open and closed-reference methods. We also demonstrated that for the greedy algorithms VSEARCH produced assignments that were comparable to those produced by USEARCH making VSEARCH a viable free and open source alternative to USEARCH. Further interrogation of the reference-based methods indicated that when USEARCH or VSEARCH were used to identify the closest reference, the OTU assignments were sensitive to the order of the reference sequences because the reference sequences can be identical over the region being considered. More troubling was the observation that while both USEARCH and VSEARCH have a

  10. General-relativistic celestial mechanics. I. Method and definition of reference systems

    SciTech Connect

    Damour, T. Departement d'Astrophysique Relativiste et de Cosmologie, Observatoire de Paris, Centre National de la Recherche Scientifique, 92195 Meudon CEDEX, France ); Soffel, M.; Xu, C. )

    1991-05-15

    We present a new formalism for treating the general-relativistic celestial mechanics of systems of {ital N} arbitrarily composed and shaped, weakly self-gravitating, rotating, deformable bodies. This formalism is aimed at yielding a complete description, at the first post-Newtonian approximation level, of (i) the global dynamics of such {ital N}-body systems ( external problem''), (ii) the local gravitational structure of each body ( internal problem''), and, (iii) the way the external and the internal problems fit together ( theory of reference systems''). This formalism uses in a complementary manner {ital N}+1 coordinate charts (or reference systems''): one global'' chart for describing the overall dynamics of the {ital N} bodies, and {ital N} local'' charts adapted to the separate description of the structure and environment of each body. The main tool which allows us to develop, in an elegant manner, a constructive theory of these {ital N}+1 reference systems is a systematic use of a particular exponential'' parametrization of the metric tensor which has the effect of linearizing both the field equations, and the transformation laws under a change of reference system. This linearity allows a treatment of the first post-Newtonian relativistic celestial mechanics which is, from a structural point of view, nearly as simple and transparent as its Newtonian analogue.

  11. Negotiating with Subscription Agencies.

    ERIC Educational Resources Information Center

    McQueen, Judy; Basch, N. Bernard

    1991-01-01

    This first in a two-part series on how librarians can negotiate services and prices with subscription agencies focuses on how vendors operate. Factors that influence agency costs, revenues, and service charges are described, including economies of scale, discounts from publishers, and prepayment and cash flow. (seven references) (LRW)

  12. United States environmental protection agency perchlorate method 332.0. Statistically sound recovery studies in simulated drinking water.

    PubMed

    Vanatta, L E; Slingsby, R W

    2011-09-01

    This research is a continuation of an earlier work, which evaluated the United States Environmental Protection Agency's Perchlorate Method 332.0, in which standards were prepared in deionized water over an extended concentration range (i.e., to a maximum of 200 μg/L). This current paper investigates the performance of the same method in which standards were made in simulated drinking water. A microbore format with a 15-μL injection volume was employed to conduct a recovery study and generate recovery curves (which hold the key to a statistically sound assessment of method performance in more complex matrices). The maximum analyte concentration range was 1 to 200 μg/L. For various subset concentration ranges, recovery evaluations were made using both raw peak-area data and analyte responses scaled by the internal standard (ISTD). The results indicate that in complicated matrices such as drinking water, ISTDs may not provide simultaneously high precision and recovery.

  13. Homogenizing Responses to Different Survey Questions on the Same Topic: Proposal of a Scale Homogenization Method Using a Reference Distribution.

    PubMed

    de Jonge, Tineke; Veenhoven, Ruut; Arends, Lidia

    2014-01-01

    Survey data are often used for comparison purposes, such as comparisons across nations or comparisons over time. To be effective, this would require equivalent questions and equivalent responses options to the questions. Yet there is a lot of variation in the response scales used, which, for example, differ in the number of response options used and the labeling of these options. This is the case in happiness research, and as a result most of the research data in this field is incomparable. Several methods have been proposed to transform ratings on verbal response scales to a common numerical scale, typically ranging from 0 to 10. In this paper we give an overview of the progress made in those Scale Homogenization methods over time. We describe two early methods: Linear Stretch and the Semantic Judgement of Fixed Word Value Method. Next we discuss the Semantic Judgement of Word Value in Context Method in more detail. Based on these discussions we propose a new Reference Distribution Method. We apply the Semantic Judgement of Word Value in Context and the Reference Distribution Methods to data on happiness in The Netherlands for the years 1989-2009. We show that the Reference Distribution Method produces comparable time series on different questions and that it allows discontinuities in data to be corrected.

  14. Library Reference Services.

    ERIC Educational Resources Information Center

    Miller, Constance; And Others

    1985-01-01

    Seven articles on library reference services highlight reference obsolescence in academic libraries, major studies of unobtrusive reference tests, methods for evaluating reference desk performance, reference interview evaluation, problems of reference desk control, online searching by end users, and reference collection development in…

  15. DEMONSTRATION BULLETIN: FIELD ANALYTICAL SCREENING PROGRAM: PCP METHOD - U.S. ENVIRONMENTAL PROTECTION AGENCY

    EPA Science Inventory

    The Superfund Innovative Technology Evaluation (SITE) Program evaluates new technologies to assess their effectiveness. This bulletin summarizes results from the 1993 SITE demonstration of the Field Analytical Screening Program (FASP) Pentachlorophenol (PCP) Method to determine P...

  16. Kernel reconstruction methods for Doppler broadening — Temperature interpolation by linear combination of reference cross sections at optimally chosen temperatures

    DOE PAGES

    Ducru, Pablo; Josey, Colin; Dibert, Karia; ...

    2017-01-25

    This paper establishes a new family of methods to perform temperature interpolation of nuclear interactions cross sections, reaction rates, or cross sections times the energy. One of these quantities at temperature T is approximated as a linear combination of quantities at reference temperatures (Tj). The problem is formalized in a cross section independent fashion by considering the kernels of the different operators that convert cross section related quantities from a temperature T0 to a higher temperature T — namely the Doppler broadening operation. Doppler broadening interpolation of nuclear cross sections is thus here performed by reconstructing the kernel of themore » operation at a given temperature T by means of linear combination of kernels at reference temperatures (Tj). The choice of the L2 metric yields optimal linear interpolation coefficients in the form of the solutions of a linear algebraic system inversion. The optimization of the choice of reference temperatures (Tj) is then undertaken so as to best reconstruct, in the L∞ sense, the kernels over a given temperature range [Tmin,Tmax]. The performance of these kernel reconstruction methods is then assessed in light of previous temperature interpolation methods by testing them upon isotope 238U. Temperature-optimized free Doppler kernel reconstruction significantly outperforms all previous interpolation-based methods, achieving 0.1% relative error on temperature interpolation of 238U total cross section over the temperature range [300 K,3000 K] with only 9 reference temperatures.« less

  17. Kernel reconstruction methods for Doppler broadening - Temperature interpolation by linear combination of reference cross sections at optimally chosen temperatures

    NASA Astrophysics Data System (ADS)

    Ducru, Pablo; Josey, Colin; Dibert, Karia; Sobes, Vladimir; Forget, Benoit; Smith, Kord

    2017-04-01

    This article establishes a new family of methods to perform temperature interpolation of nuclear interactions cross sections, reaction rates, or cross sections times the energy. One of these quantities at temperature T is approximated as a linear combination of quantities at reference temperatures (Tj). The problem is formalized in a cross section independent fashion by considering the kernels of the different operators that convert cross section related quantities from a temperature T0 to a higher temperature T - namely the Doppler broadening operation. Doppler broadening interpolation of nuclear cross sections is thus here performed by reconstructing the kernel of the operation at a given temperature T by means of linear combination of kernels at reference temperatures (Tj). The choice of the L2 metric yields optimal linear interpolation coefficients in the form of the solutions of a linear algebraic system inversion. The optimization of the choice of reference temperatures (Tj) is then undertaken so as to best reconstruct, in the L∞ sense, the kernels over a given temperature range [Tmin ,Tmax ]. The performance of these kernel reconstruction methods is then assessed in light of previous temperature interpolation methods by testing them upon isotope 238U. Temperature-optimized free Doppler kernel reconstruction significantly outperforms all previous interpolation-based methods, achieving 0.1% relative error on temperature interpolation of 238U total cross section over the temperature range [ 300 K , 3000 K ] with only 9 reference temperatures.

  18. Methods of RNA preparation affect mRNA abundance quantification of reference genes in pig maturing oocytes.

    PubMed

    Wang, Y-K; Li, X; Song, Z-Q; Yang, C-X

    2017-10-01

    To ensure accurate normalization and quantification of target RNA transcripts using reverse transcription quantitative polymerase chain reaction (RT-qPCR), most studies focus on the identification of stably expressed gene(s) as internal reference. However, RNA preparation methods could also be an important factor, especially for test samples of limited quantity (e.g. oocytes). In this study, we aimed to select appropriate reference gene(s), and evaluate the effect of RNA preparation methods on gene expression quantification in porcine oocytes and cumulus cells during in vitro maturation. Expression profiles of seven genes (GAPDH, 18S, YWHAG, BACT, RPL4, HPRT1 and PPIA) were examined, on RNA samples extracted from cumulus cells (RNeasy Kit) and oocytes (RNeasy Kit and Lysis Kit) during in vitro maturation, respectively. Interestingly, different RNA preparation methods were found to potentially affect the quantification of reference gene expression in pig oocytes cultured in vitro. After geNorm analyses, the most suitable genes for normalization were identified, GAPDH/18S for cumulus cells and YWHAG/BACT for oocytes, respectively. Thus, our results provide useful data and information on the selection of better reference genes and RNA preparation method for related functional studies. © 2017 Blackwell Verlag GmbH.

  19. Reference test methods for total water in lint cotton by Karl Fischer Titration and low temperature distillation

    USDA-ARS?s Scientific Manuscript database

    In a study of comparability of total water contents (%) of conditioned cottons by Karl Fischer Titration (KFT) and Low Temperature Distillation (LTD) reference methods, we demonstrated a match of averaged results based on a large number of replications and weighing the test specimens at the same tim...

  20. Correction of self-absorption effect in calibration-free laser-induced breakdown spectroscopy by an internal reference method.

    PubMed

    Sun, Lanxiang; Yu, Haibin

    2009-07-15

    A simplified procedure for correcting self-absorption effect was proposed in calibration-free laser-induced breakdown spectroscopy (CF-LIBS). In typical LIBS measurement conditions, the plasma produced is often optically thick, especially for the strong lines of major elements. The selection of self-absorption lines destroys the performance of CF-LIBS, and the familiar correction method based on the curve of growth is complex in implementation. The procedure we proposed, named internal reference for self-absorption correction (IRSAC), first chose an internal reference line for each species, then compared other spectral line intensity of the same species with the reference line to estimate the self-absorption degrees of other spectral lines, and finally achieved an optimal correction by a regressive algorithm. The self-absorption effect of the selected reference line can be ignored, since the reference line with high excitation energy of the upper level is slightly affected by the self-absorption. Through the IRSAC method, the points on the Boltzmann plot become more regular, and the evaluations of the plasma temperature and material composition are more accurate than the basic CF-LIBS.

  1. Reference-free direct digital lock-in method and apparatus

    NASA Technical Reports Server (NTRS)

    Henry, James E. (Inventor); Leonard, John A. (Inventor)

    2000-01-01

    A reference-free direct digital lock-in system (RDDL 10) has a first input coupled to a periodic electrical signal and an output for outputting an indication of a magnitude of a desired periodic signal component. The RDDL also has a second input for receiving a signal (9) that specifies a reference period value, and operates to autonomously generate a lock-in reference signal having a specified period and a phase that is adjusted to maximize a magnitude of the outputted desired periodic signal component. In an embodiment of a measurement system that includes the RDDL 10 an optical source provides a chopped light beam having wavelengths within a predetermined range of wavelengths, and the periodic electrical signal is generated by at least one photodetector that is illuminated by the chopped light beam. In this embodiment the measurement system characterizes, for at least one wavelength of light that is generated by the optical source, a spectral response of the at least one photodetector. The RDDL can operate in nonreal-time upon previously generated and stored digital equivalent values of the periodic electrical signal or signals.

  2. System and method for tuning adjusting the central frequency of a laser while maintaining frequency stabilization to an external reference

    NASA Technical Reports Server (NTRS)

    Livas, Jeffrey (Inventor); Thorpe, James I. (Inventor); Numata, Kenji (Inventor)

    2011-01-01

    A method and system for stabilizing a laser to a frequency reference with an adjustable offset. The method locks a sideband signal generated by passing an incoming laser beam through the phase modulator to a frequency reference, and adjusts a carrier frequency relative to the locked sideband signal by changing a phase modulation frequency input to the phase modulator. The sideband signal can be a single sideband (SSB), dual sideband (DSB), or an electronic sideband (ESB) signal. Two separate electro-optic modulators can produce the DSB signal. The two electro-optic modulators can be a broadband modulator and a resonant modulator. With a DSB signal, the method can introduce two sinusoidal phase modulations at the phase modulator. With ESB signals, the method can further drive the optical phase modulator with an electrical signal with nominal frequency OMEGA(sub 1) that is phase modulated at a frequency OMEGA(sub 2)

  3. Year-long validation study and reference values for urinary amino acids using a reversed-phase HPLC method.

    PubMed

    Venta, R

    2001-03-01

    Reversed-phase HPLC (RP-HPLC) has become an alternative to ion-exchange chromatography for amino acid analysis in biological fluids. However, validation studies for its urine application are limited, and the corresponding reference values have not been reported extensively. We studied the long-term performance of a commercial HPLC method for urine amino acid analysis and established specific age-related reference values for urine amino acid excretion. Method performance was continuously assessed by recovery and precision studies with urine samples and controls, respectively. Healthy individuals were prospectively analyzed throughout a 5-year period. Excretion of individual amino acids, expressed as mmol/mol of creatinine, was included in six age-related groups for random urine samples (0-1 month, 1-12 months, 1-3 years, 3-8 years, 8-16 years, and >16 years) and in two groups for 24-h urine collections (8-16 years and >16 years). Over a 1-year period, CVs for retention times were <0.5% and 3.3% for within- and between-run imprecision, respectively. For amino acid concentrations, within-run CVs were 2.9-17% and between-run CVs were 7.1-46% for the same period. Amino acid recoveries were 78-122%. Reference intervals for 35 amino acids were calculated and compared with the concentrations observed in patients diagnosed with specific pathologies. A few statistically significant differences were found between the reference intervals derived using random and 24-h urine collections. Long-term reliability of the RP-HPLC method for urine amino acid analysis has been demonstrated. Representative age-related reference intervals for the RP-HPLC method in both random urine and 24-h urine collections have been established, and their feasibility for diagnosis of aminoaciduria has been shown. These intervals could serve as a guide for laboratories changing to HPLC methods.

  4. Verbal Auditory Cueing of Improvisational Dance: A Proposed Method for Training Agency in Parkinson's Disease.

    PubMed

    Batson, Glenna; Hugenschmidt, Christina E; Soriano, Christina T

    2016-01-01

    Dance is a non-pharmacological intervention that helps maintain functional independence and quality of life in people with Parkinson's disease (PPD). Results from controlled studies on group-delivered dance for people with mild-to-moderate stage Parkinson's have shown statistically and clinically significant improvements in gait, balance, and psychosocial factors. Tested interventions include non-partnered dance forms (ballet and modern dance) and partnered (tango). In all of these dance forms, specific movement patterns initially are learned through repetition and performed in time-to-music. Once the basic steps are mastered, students may be encouraged to improvise on the learned steps as they perform them in rhythm with the music. Here, we summarize a method of teaching improvisational dance that advances previous reported benefits of dance for people with Parkinson's disease (PD). The method relies primarily on improvisational verbal auditory cueing with less emphasis on directed movement instruction. This method builds on the idea that daily living requires flexible, adaptive responses to real-life challenges. In PD, movement disorders not only limit mobility but also impair spontaneity of thought and action. Dance improvisation demands open and immediate interpretation of verbally delivered movement cues, potentially fostering the formation of spontaneous movement strategies. Here, we present an introduction to a proposed method, detailing its methodological specifics, and pointing to future directions. The viewpoint advances an embodied cognitive approach that has eco-validity in helping PPD meet the changing demands of daily living.

  5. EPA (Environmental Protection Agency) method study 25, method 602, purgeable aromatics. Report for Sep 79-Dec 82

    SciTech Connect

    Warner, B.J.; Finke, J.M.; Gable, R.C.; Strobel, J.E.; Snyder, A.D.

    1984-05-01

    The experimental design and the results of an interlaboratory study for an analytical method to detect purgeable aromatics in water are described herein. The method, EPA Method 602, Purgeable Aromatics, employs a purge-and-trap chromatographic technique for determination of seven aromatic hydrocarbon analytes in water matrices. The three Youden pairs of spiking solutions used in this study contained benzene, chlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, ethylbenzene and toluene. The six water types used in the study were distilled water, drinking water, surface water, and three wastewater samples from industries employing or producing aromatic hydrocarbons. Twenty laboratories participated in the Method 602 validation study. The participating laboratories supplied their individual distilled, drinking, and surface water samples. Monsanto Research Corporation (MRC) supplied the three industrial wastewater samples. The statistical analyses and conclusions reached in this report are based on the analytical data obtained by the 20 participating laboratories.

  6. Toward standardization of carbohydrate-deficient transferrin (CDT) measurements: I. Analyte definition and proposal of a candidate reference method.

    PubMed

    Jeppsson, Jan-Olof; Arndt, Torsten; Schellenberg, François; Wielders, Jos P M; Anton, Raymond F; Whitfield, John B; Helander, Anders

    2007-01-01

    An alcohol-associated change in the serum transferrin glycoform pattern, carbohydrate-deficient transferrin (CDT), is used as a biomarker of chronic moderate to heavy alcohol consumption. A current limitation in CDT analysis is the lack of standardization, which hampers clinical and analytical comparison between studies. This situation prompted initiation of a Working Group (WG) on CDT Standardization under the auspices of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). The standardization work aims to define and validate the analyte, select a reference method, work out procedures for the production of reference materials, and make suggestions for the clinical usage of CDT. The first recommendation of the WG is that disialotransferrin should be the primary target molecule for CDT measurement and the single analyte on which CDT standardization is based. It is further recommended that HPLC should be the analytical principle considered as the basis of an interim reference method until a suitable mass spectrometric reference method is established. In clinical use, CDT should be expressed in a relative amount (% CDT), to compensate for variations in the total transferrin concentration.

  7. 40 CFR Table A-1 to Subpart A of... - Summary of Applicable Requirements for Reference and Equivalent Methods for Air Monitoring of...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Reference and Equivalent Methods for Air Monitoring of Criteria Pollutants A Table A-1 to Subpart A of Part...) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS General Provisions Pt. 53, Subpt. A, Table A-1 Table A-1 to Subpart A of Part 53—Summary of Applicable Requirements for Reference and Equivalent...

  8. 40 CFR Table A-1 to Subpart A of... - Summary of Applicable Requirements for Reference and Equivalent Methods for Air Monitoring of...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Reference and Equivalent Methods for Air Monitoring of Criteria Pollutants A Table A-1 to Subpart A of Part...) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS General Provisions Pt. 53, Subpt. A, Table A-1 Table A-1 to Subpart A of Part 53—Summary of Applicable Requirements for Reference and...

  9. 40 CFR Table A-1 to Subpart A of... - Summary of Applicable Requirements for Reference and Equivalent Methods for Air Monitoring of...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Reference and Equivalent Methods for Air Monitoring of Criteria Pollutants A Table A-1 to Subpart A of Part...) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS General Provisions Pt. 53, Subpt. A, Table A-1 Table A-1 to Subpart A of Part 53—Summary of Applicable Requirements for Reference and...

  10. 40 CFR Table A-1 to Subpart A of... - Summary of Applicable Requirements for Reference and Equivalent Methods for Air Monitoring of...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Reference and Equivalent Methods for Air Monitoring of Criteria Pollutants A Table A-1 to Subpart A of Part...) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS General Provisions Pt. 53, Subpt. A, Table A-1 Table A-1 to Subpart A of Part 53—Summary of Applicable Requirements for Reference and...

  11. 40 CFR Table A-1 to Subpart A of... - Summary of Applicable Requirements for Reference and Equivalent Methods for Air Monitoring of...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Reference and Equivalent Methods for Air Monitoring of Criteria Pollutants A Table A-1 to Subpart A of Part...) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS General Provisions Pt. 53, Subpt. A, Table A-1 Table A-1 to Subpart A of Part 53—Summary of Applicable Requirements for Reference and...

  12. The utility of optical detection system (qPCR) and bioinformatics methods in reference gene expression analysis

    NASA Astrophysics Data System (ADS)

    Skarzyńska, Agnieszka; Pawełkowicz, Magdalena; PlÄ der, Wojciech; Przybecki, Zbigniew

    2016-09-01

    Real-time quantitative polymerase chain reaction is consider as the most reliable method for gene expression studies. However, the expression of target gene could be misinterpreted due to improper normalization. Therefore, the crucial step for analysing of qPCR data is selection of suitable reference genes, which should be validated experimentally. In order to choice the gene with stable expression in the designed experiment, we performed reference gene expression analysis. In this study genes described in the literature and novel genes predicted as control genes, based on the in silico analysis of transcriptome data were used. Analysis with geNorm and NormFinder algorithms allow to create the ranking of candidate genes and indicate the best reference for flower morphogenesis study. According to the results, genes CACS and CYCL were characterised the most stable expression, but the least suitable genes were TUA and EF.

  13. Influence of applied volume on efficacy of 3-minute surgical reference disinfection method prEN 12791.

    PubMed

    Kampf, Günter; Ostermeyer, Christiane

    2004-12-01

    For assessment of the efficacy of surgical hand disinfection, European reference method prEN 12791 prescribes that the hands must be kept wet with the reference alcohol for 3 min regardless of the applied volume. The aim of this study was to determine whether the applied volume of the reference disinfectant n-propanol (60%, vol/vol) influences the effect on the resident hand flora. Ten experiments with 200 reference disinfections were analyzed. Hands were washed for 1 min with soap. The bacterial prevalue was obtained by rubbing fingertips in tryptic soy broth for 1 min. After this, each subject treated the hands with n-propanol (60%, vol/vol) by using as many portions as necessary to keep hands wet for a total of 3 min. Bacterial postvalues (immediate effect) were obtained for one hand, and the other hand was gloved for 3 h. After the gloves were taken off, a second postvalue was obtained (sustained effect). Most surgical reference disinfections (73%) were achieved with 9 ml of the reference alcohol, followed by 12 ml (24%) and 6 ml (3%). There was no significant difference between the mean log10 reduction values for the three treatment groups, both in terms of the immediate effect (P = 0.333, as determined by analysis of variance) and in terms of the sustained effect (P = 0.442). A higher number of portions did not correlate with a higher reduction factor (for immediate effect, Pearson's correlation coefficient = -0.028 [P = 0.689]; for sustained effect, Pearson's correlation coefficient = 0.059 [P = 0.404]). If the hands were kept wet with the reference alcohol for the total application time, the applied volume could vary, but this did not alter the efficacy.

  14. The Kjeldahl method as a primary reference procedure for total protein in certified reference materials used in clinical chemistry. II. Selection of direct Kjeldahl analysis and its preliminary performance parameters.

    PubMed

    Vinklárková, Bára; Chromý, Vratislav; Šprongl, Luděk; Bittová, Miroslava; Rikanová, Milena; Ohnútková, Ivana; Žaludová, Lenka

    2015-01-01

    To select a Kjeldahl procedure suitable for the determination of total protein in reference materials used in laboratory medicine, we reviewed in our previous article Kjeldahl methods adopted by clinical chemistry and found an indirect two-step analysis by total Kjeldahl nitrogen corrected for its nonprotein nitrogen and a direct analysis made on isolated protein precipitates. In this article, we compare both procedures on various reference materials. An indirect Kjeldahl method gave falsely lower results than a direct analysis. Preliminary performance parameters qualify the direct Kjeldahl analysis as a suitable primary reference procedure for the certification of total protein in reference laboratories.

  15. Data page reconstruction method based on two-dimensional soft output Viterbi algorithm with self reference for holographic data storage

    NASA Astrophysics Data System (ADS)

    Koo, Keunhwi; Kim, Soo-Yong; Jeong, Jae Jin; Kim, Sang Woo

    2014-09-01

    This study introduces a two-dimensional (2D) partial response maximum likelihood (PRML) method to reconstruct a degraded data page having 2D inter-symbol interference for holographic data storage. The proposed 2D PRML method consists of 2D partial response (PR) target, 2D equalizer using least mean square algorithm, and 2D soft output Viterbi algorithm (SOVA) having just two one-dimensional (1D) SOVAs in horizontal and vertical directions. To accurately organize a trellis diagram of the 1D SOVA in structural accordance with the 2D PR target, this study proposes the self-reference process for the extrinsic information in the 1D SOVA. Finally, simulation results show that the proposed method has bit error rate performance similar to that of modified 2D SOVA having four 1D SOVAs despite the relatively low computational complexity. Moreover, parallel processing is possible in the two 1D SOVAs through the self-reference process.

  16. Bias adjustment for hydrological modelling - Comparing methods and reference data sets

    NASA Astrophysics Data System (ADS)

    Kpogo-Nuwoklo, Komlan A.; Fischer, Madlen; Rust, Henning W.; Ulbrich, Uwe; Meredith, Edmund; Vagenas, Christos

    2017-04-01

    In the context of the HORIZON 2020 project BINGO (Bringing INnovation to onGOing water management), high-resolution meteorological driving data from the COSMO-CLM regional model are to be bias corrected to be used for various hydrological models. For many of the variables considered, the climate model simulations show a systematic deviation from observation. The expectation value of this error is referred to as bias. To achieve better statistical correspondence between model simulations and the corresponding observational data, it is common practice to adjust this bias prior to subsequent impact studies. A plethora of approaches for bias adjustment have been developed, ranging from simple scaling to more sophisticated approaches. In BINGO, two different approaches are currently used: i) one based on Generalized Linear Model using seasonal covariates and ii) Cumulative Distribution Function Trans- form (CDF-t). While the former aims at correcting the climatological seasonal cycle of simulations to match that of observations, the latter (CDF-t) is based on a cumulative distribution function (CDF) and thus ensures a correction of the full distribution. Focusing on precipitation, a comparison between these two approaches is carried out with two different reference data sets (WATCH and E-OBS). The comparison is mainly based on statistics such as the relative frequency of wet days, the monthly mean and variance. The Wupper catchment (Germany), which is one of the six research sites studied in BINGO, is used as a showcase.

  17. Accuracy of ELISA detection methods for gluten and reference materials: a realistic assessment.

    PubMed

    Diaz-Amigo, Carmen; Popping, Bert

    2013-06-19

    The determination of prolamins by ELISA and subsequent conversion of the resulting concentration to gluten content in food appears to be a comparatively simple and straightforward process with which many laboratories have years-long experience. At the end of the process, a value of gluten, expressed in mg/kg or ppm, is obtained. This value often is the basis for the decision if a product can be labeled gluten-free or not. On the basis of currently available scientific information, the accuracy of the obtained values with commonly used commercial ELISA kits has to be questioned. Although recently several multilaboratory studies have been conducted in an attempt to emphasize and ensure the accuracy of the results, data suggest that it was the precision of these assays, not the accuracy, that was confirmed because some of the underlying assumptions for calculating the gluten content lack scientific data support as well as appropriate reference materials for comparison. This paper discusses the issues of gluten determination and quantification with respect to antibody specificity, extraction procedures, reference materials, and their commutability.

  18. Evaluation of the ERETIC method as an improved quantitative reference for 1H HR-MAS spectroscopy of prostate tissue.

    PubMed

    Albers, Mark J; Butler, Thomas N; Rahwa, Iman; Bao, Nguyen; Keshari, Kayvan R; Swanson, Mark G; Kurhanewicz, John

    2009-03-01

    The Electronic REference To access In vivo Concentrations (ERETIC) method was applied to (1)H HR-MAS spectroscopy. The accuracy, precision, and stability of ERETIC as a quantitative reference were evaluated in solution and human prostate tissue samples. For comparison, the reliability of 3-(trimethylsilyl)propionic-2,2,3,3-d(4) acid (TSP) as a quantitation reference was also evaluated. The ERETIC and TSP peak areas were found to be stable in solution over the short-term and long-term, with long-term relative standard deviations (RSDs) of 4.10% and 2.60%, respectively. Quantification of TSP in solution using the ERETIC peak as a reference and a calibrated, rotor-dependent conversion factor yielded results with a precision < or =2.9% and an accuracy error < or =4.2% when compared with the expected values. The ERETIC peak area reproducibility was superior to TSP's reproducibility, corrected for mass, in both prostate surgical and biopsy samples (4.53% vs. 21.2% and 3.34% vs. 31.8%, respectively). Furthermore, the tissue TSP peaks exhibited only 27.5% of the expected area, which would cause an overestimation of metabolite concentrations if used as a reference. The improved quantification accuracy and precision provided by ERETIC may enable the detection of smaller metabolic differences that may exist between individual tissue samples and disease states.

  19. Development of High-purity Certified Reference Materials for 17 Proteinogenic Amino Acids by Traceable Titration Methods.

    PubMed

    Kato, Megumi; Yamazaki, Taichi; Kato, Hisashi; Eyama, Sakae; Goto, Mari; Yoshioka, Mariko; Takatsu, Akiko

    2015-01-01

    To ensure the reliability of amino acid analyses, the National Metrology Institute of Japan of the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) has developed high-purity certified reference materials (CRMs) for 17 proteinogenic amino acids. These CRMs are intended for use as primary reference materials to enable the traceable quantification of amino acids. The purity of the present CRMs was determined based on two traceable methods: nonaqueous acidimetric titration and nitrogen determination by the Kjeldahl method. Since neither method could distinguish compounds with similar structures, such as amino acid-related impurities, impurities were thoroughly quantified by combining several HPLC methods, and subtracted from the obtained purity of each method. The property value of each amino acid was calculated as a weighted mean of the corrected purities by the two methods. The uncertainty of the property value was obtained by combining measurement uncertainties of the two methods, a difference between the two methods, the uncertainty from the contribution of impurities, and the uncertainty derived from inhomogeneity. The uncertainty derived from instability was considered to be negligible based on stability monitoring of some CRMs. The certified value of each amino acid, property value with uncertainty, was given for both with or without enantiomeric separation.

  20. Detection of Salmonella in Foods Using a Reference PN-ISO Method and an Alternative Method Based on Loop-mediated Isothermal Amplification Coupled with Bioluminescence.

    PubMed

    Sarowska, Jolanta; Frej-Mądrzak, Magdalena; Jama-Kmiecik, Agnieszka; Kilian, Anna; Teryks-Wołyniec, Dorota; Choroszy-Król, Irena

    2016-01-01

    Salmonella, one of the primary indicators of food safety, is a common cause of food poisoning of an epidemic nature around the world. These microorganisms can colonize the gastrointestinal tract of both people and animals, and next contaminate not only eggs, milk, meat and dairy products, but also vegetables, fruit, grains and even spices. The aim of this study was to analyze the frequency of detection of Salmonella spp. in food samples using a reference PN-ISO method and an alternative method based on loop-mediated isothermal amplification (LAMP) coupled with bioluminescence. Food samples were obtained in cooperation with the State Sanitary-Epidemiological Station in Wrocław. Dairy products, meat, fish, pastry and confectionery, vegetables, herbs and spices were analyzed. The food samples were examined using a standard culturing method according to PN-ISO 6579:2003 for Salmonella spp. and an alternative method based on the isothermal amplification and bioluminescence phenomenon using the 3M MDS device. In 399 tested food samples in 8 materials, using both the reference and the alternative LAMP-based method, the presence of salmonella was confirmed. The results obtained show the 100% sensitivity, specificity and accuracy of the presented alternative, LAMP-based technique compared to the reference PN-ISO method. The alternative method using isothermal amplification and bioluminescence makes it possible to detect Salmonella in foods in a much shorter time than the referential culturing method.

  1. Delivery Path Length and Holding Tree Minimization Method of Securities Delivery among the Registration Agencies Connected as Non-Tree

    NASA Astrophysics Data System (ADS)

    Shimamura, Atsushi; Moritsu, Toshiyuki; Someya, Harushi

    To dematerialize the securities such as stocks or cooporate bonds, the securities were registered to account in the registration agencies which were connected as tree. This tree structure had the advantage in the management of the securities those were issued large amount and number of brands of securities were limited. But when the securities such as account receivables or advance notes are dematerialized, number of brands of the securities increases extremely. In this case, the management of securities with tree structure becomes very difficult because of the concentration of information to root of the tree. To resolve this problem, using the graph structure is assumed instead of the tree structure. When the securities are kept with tree structure, the delivery path of securities is unique, but when securities are kept with graph structure, path of delivery is not unique. In this report, we describe the requirement of the delivery path of securities, and we describe selecting method of the path.

  2. Improving the performance of US Environmental Protection Agency Method 300.1 for monitoring drinking water compliance.

    PubMed

    Wagner, Herbert P; Pepich, Barry V; Hautman, Daniel P; Munch, David J

    2003-09-05

    In 1998, the United States Environmental Protection Agency (EPA) promulgated the maximum contaminant level (MCL) for bromate in drinking water at 10 microg/l, and the method for compliance monitoring of bromate in drinking water was established under Stage 1 of the Disinfectants/Disinfection By-Products Rule (D/DBP) as EPA Method 300.1. In January 2002, the United States Food and Drug Administration (FDA) regulated the bromate concentration in bottled waters at 10 microg/l. EPA anticipates proposing additional methods, which have improved performance for bromate monitoring, in addition to EPA Method 300.1, in the Stage 2 DBP Rule. Until the Stage 2 Rule is promulgated, EPA Method 300.1 will continue to be the only method approved for compliance monitoring of bromate. This manuscript describes the work completed at EPA's Technical Support Center (TSC) to assess the performance of recently developed suppressor technologies toward improving the trace level performance of EPA Method 300.1, specifically for the analysis of trace levels of bromate in high ionic matrices. Three different types of Dionex suppressors were evaluated. The baseline noise, return to baseline after the water dip, detection limits, precision and accuracy, and advantages/disadvantages of each suppressor are discussed. Performance data for the three different suppressors indicates that chemical suppression of the eluent, using the AMMS III suppressor, is the most effective means to reduce baseline noise, resulting in the best resolution and the lowest bromate detection limits, even when a high ionic matrix is analyzed. Incorporation of the AMMS III suppressor improves the performance of EPA Method 300.1 at and below 5.0 microg/l and is a quick way for laboratories to improve their bromate compliance monitoring.

  3. 40 CFR 98.7 - What standardized methods are incorporated by reference into this part?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Method for Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb Calorimeter, IBR approved for § 98.254... Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb Calorimeter (Precision Method), IBR approved for... Residues from Combustion of Coal and Coke by Inductively Coupled Plasma—Atomic Emission Spectrometry, IBR...

  4. 40 CFR 98.7 - What standardized methods are incorporated by reference into this part?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Method for Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb Calorimeter, IBR approved for § 98.254... Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb Calorimeter (Precision Method), IBR approved for... Inductively Coupled Plasma—Atomic Emission Spectrometry, IBR approved for § 98.144(b). (46) ASTM D2879-97...

  5. 40 CFR 98.7 - What standardized methods are incorporated by reference into this part?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Method for Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb Calorimeter, IBR approved for § 98.254... Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb Calorimeter (Precision Method), IBR approved for... Inductively Coupled Plasma—Atomic Emission Spectrometry, IBR approved for § 98.144(b). (46) ASTM D2879-97...

  6. 40 CFR 98.7 - What standardized methods are incorporated by reference into this part?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (Reapproved 2007) Standard Test Method for Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb Calorimeter... of Gaseous Fuels, IBR approved for §§ 98.34(a) and 98.254(e). (21) ASTM D3682-01 (Reapproved 2006) Standard Test Method for Major and Minor Elements in Combustion Residues from Coal Utilization Processes...

  7. Methods of Forecasting Manpower Requirements with Special Reference to the Province of Ontario.

    ERIC Educational Resources Information Center

    Mehmet, Ozay

    The most generally accepted approaches of quantitatively forecasting manpower requirements by industries and occupations are described and evaluated. The operational steps of each forecasting technique are spelled out fully and illustrations of their use are made for (1) the econometric method, (2) the productivity method, (3) the trend projection…

  8. Comparison of the Reference Intervals Used for the Evaluation of Maternal Thyroid Function During Pregnancy Using Sequential and Nonsequential Methods

    PubMed Central

    Fan, Jian-Xia; Yang, Shuai; Qian, Wei; Shi, Feng-Tao; Huang, He-Feng

    2016-01-01

    Background: Maternal thyroid dysfunction is common during pregnancy, and physiological changes during pregnancy can lead to the overdiagnosis of hyperthyroidism and misdiagnosis of hypothyroidism with nongestation-specific reference intervals. Our aim was to compare sequential with nonsequential methods for the evaluation of thyroid function in pregnant women. Methods: We tested pregnant women who underwent their trimester prenatal screening at our hospital from February 2011 to September 2012 for serum thyroid stimulating hormone (TSH) and free thyroxine (FT4) using the Abbott and Roche kits. There were 447 and 200 patients enrolled in the nonsequential and sequential groups, respectively. The central 95% range between the 2.5th and the 97.5th percentiles was used as the reference interval for the thyroid function parameter. Results: The nonsequential group exhibited a significantly larger degree of dispersion in the TSH reference interval during the 2nd and 3rd trimesters as measured using both the Abbott and Roche kits (all P < 0.05). The TSH reference intervals were significantly larger in the nonsequential group than in the sequential group during the 3rd trimester as measured with both the Abbott (4.95 vs. 3.77 mU/L, P < 0.001) and Roche kits (6.62 vs. 5.01 mU/L, P = 0.004). The nonsequential group had a significantly larger FT4 reference interval as measured with the Abbott kit during all trimesters (12.64 vs. 5.82 pmol/L; 7.96 vs. 4.77 pmol/L; 8.10 vs. 4.77 pmol/L, respectively, all P < 0.05), whereas a significantly larger FT4 reference interval was only observed during the 2nd trimester with the Roche kit (7.76 vs. 5.52 pmol/L, P = 0.002). Conclusions: It was more reasonable to establish reference intervals for the evaluation of maternal thyroid function using the sequential method during each trimester of pregnancy. Moreover, the exclusion of pregnancy-related complications should be considered in the inclusion criteria for thyroid function tests. PMID

  9. Optical coherence tomography as a reference method for the detection of nanoparticles in thin-film polymer matrices

    NASA Astrophysics Data System (ADS)

    Kirsten, Lars; Mehner, Mirko; Grombe, Ringo; Linsinger, Thomas; Emons, Hendrik; Koch, Edmund

    2013-06-01

    In food and feed production an emerging issue is the use of nanoparticles as additives to control specific properties of the products. In this context, one focus in food chemistry is the development and evaluation of measurement techniques, which could allow the detection and quantification of nanoparticles in food products. For this purpose, special noninvasive and non-destructive reference methods are required, which allow subsequent analysis with other measurement techniques. Additionally, non-invasive and fast imaging techniques are potentially appropriate for applications in the food production. Optical coherence tomography is sensitive to the backscattering of particles and is regarded as a promising technique due to its spatial resolution, the high sensitivity and the high-speed capability. In this study, the ability of OCT as a potential reference method for the detection of nanoparticles in thin-film polymer samples was investigated by determining the correlation between nanoparticle concentration and signal intensity.

  10. SPM analysis of parametric (R)-[11C]PK11195 binding images: plasma input versus reference tissue parametric methods.

    PubMed

    Schuitemaker, Alie; van Berckel, Bart N M; Kropholler, Marc A; Veltman, Dick J; Scheltens, Philip; Jonker, Cees; Lammertsma, Adriaan A; Boellaard, Ronald

    2007-05-01

    (R)-[11C]PK11195 has been used for quantifying cerebral microglial activation in vivo. In previous studies, both plasma input and reference tissue methods have been used, usually in combination with a region of interest (ROI) approach. Definition of ROIs, however, can be labourious and prone to interobserver variation. In addition, results are only obtained for predefined areas and (unexpected) signals in undefined areas may be missed. On the other hand, standard pharmacokinetic models are too sensitive to noise to calculate (R)-[11C]PK11195 binding on a voxel-by-voxel basis. Linearised versions of both plasma input and reference tissue models have been described, and these are more suitable for parametric imaging. The purpose of this study was to compare the performance of these plasma input and reference tissue parametric methods on the outcome of statistical parametric mapping (SPM) analysis of (R)-[11C]PK11195 binding. Dynamic (R)-[11C]PK11195 PET scans with arterial blood sampling were performed in 7 younger and 11 elderly healthy subjects. Parametric images of volume of distribution (Vd) and binding potential (BP) were generated using linearised versions of plasma input (Logan) and reference tissue (Reference Parametric Mapping) models. Images were compared at the group level using SPM with a two-sample t-test per voxel, both with and without proportional scaling. Parametric BP images without scaling provided the most sensitive framework for determining differences in (R)-[11C]PK11195 binding between younger and elderly subjects. Vd images could only demonstrate differences in (R)-[11C]PK11195 binding when analysed with proportional scaling due to intersubject variation in K1/k2 (blood-brain barrier transport and non-specific binding).

  11. Referred Air Method 25E: Determination of a Vapor Phase Organic Concentration in Waste Samples

    EPA Pesticide Factsheets

    This method is applicable for determining the vapor pressure of waste. The headspace vapor of the sample is analyzed for carbon content by a headspace analyzer, which uses a flame ionization detector (FID).

  12. 75 FR 9894 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-04

    ... new equivalent method for measuring concentrations of lead (Pb) in total suspended particulate matter... monitoring the concentrations of those ambient air pollutants for which EPA has established National Ambient...

  13. 75 FR 45627 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-03

    ... new equivalent method for measuring concentrations of lead (Pb) in total suspended particulate matter... monitoring the concentrations of those ambient air pollutants for which EPA has established National Ambient...

  14. EPA (Environmental Protection Agency) method study 23a, method 501. 1, trihalomethanes by purge and trap (reannouncement of PB84-169994 - see notes field for explanation)

    SciTech Connect

    Warner, B.J.; Cheng, S.C.; Friedman, C.S.; Mitrosky, S.; Snyder, A.D.

    1984-03-01

    The experimental design and the results of an interlaboratory study of U.S. Environmental Protection Agency (USEPA) method 501.1 to detect trihalomethanes in drinking water are described herein. In the method, trihalomethanes are extracted by an inert gas which is bubbled through the aqueous sample. The vapors are then trapped on a short column containing a suitable sorbent. The trapped compounds are subsequently thermally desorbed onto the head of a gas chromatographic column. An electrolytic conductivity detector is used to measure the compounds. The six concentrations of spiking solutions contained chloroform, bromodichloromethane, chlorodibromomethane and bromoform. The two waters used in the study were distilled and drinking water, both supplied by the individual laboratories. Statistical analyses and conclusions in this report are based on analytical data obtained by twenty collaborating laboratories. This report was submitted in partial fulfillment of contract 68-03-2856 by Monsanto Research Corporation under the sponsorship of the U.S. Environmental Protection Agency. The report covers a period from September 1979 to December 1982.

  15. A diagnostic for determining the quality of single-reference electron correlation methods

    NASA Technical Reports Server (NTRS)

    Lee, Timothy J.; Taylor, Peter R.

    1989-01-01

    It was recently proposed that the Euclidian norm of the t(sub 1) vector of the coupled cluster wave function (normalized by the number of electrons included in the correlation procedure) could be used to determine whether a single-reference-based electron correlation procedure is appopriate. This diagnostic, T(sub 1) is defined for use with self-consistent-field molecular orbitals and is invariant to the same orbital rotations as the coupled cluster energy. T(sub 1) is investigated for several different chemical systems which exhibit a range of multireference behavior, and is shown to be an excellent measure of the importance of non-dynamical electron correlation and is far superior to C(sub 0) from a singles and doubles configuration interaction wave function. It is further suggested that when the aim is to recover a large fraction of the dynamical electron correlation energy, a large T(sub 1) (i.e., greater than 0.02) probably indicates the need for a multireference electron correlation procedure.

  16. A diagnostic for determining the quality of single-reference electron correlation methods

    NASA Technical Reports Server (NTRS)

    Lee, Timothy J.; Taylor, Peter R.

    1989-01-01

    It was recently proposed that the Euclidian norm of the t sub 1 vector of the coupled cluster wave function (normalized by the number of electrons included in the correlation procedure) could be used to determine whether a single-reference-based electron correlation procedure is appropriate. This diagnostic, T sub 1, is defined for use with self consistent field molecular orbitals and is invariant to the same orbital rotations as the coupled cluster energy. T sub 1 is investigated for several different chemical systems which exhibit a range of multireference behavior, and is shown to be an excellent measure of the importance of nondynamical electron correlation and is far superior to C sub 0 from a singles and doubles configuration interaction wave function. It is further suggested that when the aim is to recover a large fraction of the dynamical electron correlation energy, a large T sub 1 (i.e., greater than 0.02) probably indicates the need for a multireference electron correlation procedure.

  17. A new method without reference channels used for ventricular fibrillation detection during cardiopulmonary resuscitation.

    PubMed

    Yu, Ming; Zhang, Guang; Wu, Taihu; Li, Chao; Wan, Zongming; Li, Liangzhe; Wang, Chunfei; Wang, Yalin; Lu, Hengzhi; Chen, Feng

    2016-06-01

    Ventricular fibrillation (VF) is observed as the initial rhythm in the majority of patients suffering from sudden cardiac arrest. It is vitally important to accurately recognize the initial VF rhythm and then implement electrical defibrillation. However, artifacts produced by chest compression during cardiopulmonary resuscitation (CPR) make the VF detection algorithms utilized by current automated external defibrillators (AEDs) unreliable. CPR must be traditionally interrupted for a reliable diagnosis. However, interruptions in chest compression have a deleterious effect on the success of defibrillation. The elimination of the CPR artifacts would enable compressions to continue during AED VF detection and thereby increase the likelihood of resuscitation success. We have estimated a model of this artifact by adaptively incorporating noise-assisted multivariate empirical mode decomposition (NA-MEMD) and least mean squares (LMS) and then removing the artifact from the corrupted ECGs. The simulation experiment indicated that the CPR artifact could be accurately modeled without any reference channels. We constructed a BP neural network to evaluate the results. A total of 372 VF and 645 normal sinus rhythm (SR) ECG samples were included in the analysis, and 24 CPR artifact signals were used to construct corrupted ECGs. The results indicated that at different SNR levels ranging from 0 to -12 dB, the sensitivity and specificity were always above 95 and 80 %, respectively.

  18. Solubilization methods and reference 2-DE map of cow milk fat globules.

    PubMed

    Bianchi, Laura; Puglia, Michele; Landi, Claudia; Matteoni, Silvia; Perini, Daniele; Armini, Alessandro; Verani, Margherita; Trombetta, Claudia; Soldani, Patrizia; Roncada, Paola; Greppi, Gianfranco; Pallini, Vitaliano; Bini, Luca

    2009-07-21

    Milk fat globules (MFGs) are secretory vesicles assembled and secreted by mammary epithelial cells during lactation. They consist of fat globules surrounded by a lipid bilayer membrane which is derived from the apical membrane of the lactating cells. MFGs contain, besides lipids, proteins from the apical plasma membrane and from the cytoplasmatic material. Their peculiar vesicle nature makes them a suitable and easily available source of biological material in monitoring the physiopathological state of the mammary gland. Unfortunately, the conspicuous lipidic component of MFGs consistently limits protein extraction and purification for MFG proteomic investigations. This work deals with the development of a suitable procedure for protein extraction from the cow MFGs in order to qualitatively and quantitatively improve 2-D electropherograms of the MFG. MFGs were purified from raw milk by centrifugation and then delipidated/precipitated. The resulting protein pellets were solubilised using four different 2-D SDS PAGE compatible lysis buffers. Applied methodological procedures for protein extraction and evaluation of the resulting 2-D protein-pattern are presented and discussed. Using these procedures a reference 2-D map of cow milk fat globules is also reported. The majority of the obtained identifications was represented by proteins involved in lipid synthesis or in fat globule secretion.

  19. Development of a list of reference chemicals for evaluating alternative methods to in vivo fish bioaccumulation tests.

    PubMed

    Rodriguez-Sanchez, Neus; Cronin, Mark Timothy David; Lillicrap, Adam; Madden, Judith Clare; Piechota, Przemyslaw; Tollefsen, Knut Erik

    2014-12-01

    The aim to reduce the number of animals in experiments has highlighted the need to develop and validate nonanimal methods as alternatives to bioaccumulation studies using fish. The present study details a novel 3-tier approach to develop a list of reference compounds to aid this process. The approach was based on 1) the inclusion of relevant chemical classes supported by high-quality in vivo data for the bioconcentration factor (BCF), whole-body biotransformation rates (K(met)), and metabolism characterization for rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio) (tiers I and II); and 2) the refinement to ensure a broad coverage of hydrophobicity, bioconcentration potential, molecular weight, maximum molecular diameter, whole-body biotransformation half-lives, and metabolic pathways (tier III). In silico techniques were employed to predict maximal log BCF and molecular and metabolic properties. Of the 157 compounds considered as reference compounds, 144 were supported by high-quality BCF data, 8 were supported by K(met) data, and 5 were supported by in vivo metabolism data. Additional criteria for refinement of the list of reference compounds were suggested to aid practical implementation in experimental efforts. The present list of reference compounds is anticipated to facilitate the development of alternative approaches, enhance understanding of in vivo and in vitro bioaccumulation relationships, and refine in silico BCF and metabolism predictions. © 2014 SETAC.

  20. Methods for evaluating clustering algorithms for gene expression data using a reference set of functional classes.

    PubMed

    Datta, Susmita; Datta, Somnath

    2006-08-31

    A cluster analysis is the most commonly performed procedure (often regarded as a first step) on a set of gene expression profiles. In most cases, a post hoc analysis is done to see if the genes in the same clusters can be functionally correlated. While past successes of such analyses have often been reported in a number of microarray studies (most of which used the standard hierarchical clustering, UPGMA, with one minus the Pearson's correlation coefficient as a measure of dissimilarity), often times such groupings could be misleading. More importantly, a systematic evaluation of the entire set of clusters produced by such unsupervised procedures is necessary since they also contain genes that are seemingly unrelated or may have more than one common function. Here we quantify the performance of a given unsupervised clustering algorithm applied to a given microarray study in terms of its ability to produce biologically meaningful clusters using a reference set of functional classes. Such a reference set may come from prior biological knowledge specific to a microarray study or may be formed using the growing databases of gene ontologies (GO) for the annotated genes of the relevant species. In this paper, we introduce two performance measures for evaluating the results of a clustering algorithm in its ability to produce biologically meaningful clusters. The first measure is a biological homogeneity index (BHI). As the name suggests, it is a measure of how biologically homogeneous the clusters are. This can be used to quantify the performance of a given clustering algorithm such as UPGMA in grouping genes for a particular data set and also for comparing the performance of a number of competing clustering algorithms applied to the same data set. The second performance measure is called a biological stability index (BSI). For a given clustering algorithm and an expression data set, it measures the consistency of the clustering algorithm's ability to produce biologically

  1. Establishment of quantitative analysis method for genetically modified maize using a reference plasmid and novel primers.

    PubMed

    Moon, Gi-Seong; Shin, Weon-Sun

    2012-12-01

    For the quantitative analysis of genetically modified (GM) maize in processed foods, primer sets and probes based on the 35S promoter (p35S), nopaline synthase terminator (tNOS), p35S-hsp70 intron, and zSSIIb gene encoding starch synthase II for intrinsic control were designed. Polymerase chain reaction (PCR) products (80~101 bp) were specifically amplified and the primer sets targeting the smaller regions (80 or 81 bp) were more sensitive than those targeting the larger regions (94 or 101 bp). Particularly, the primer set 35F1-R1 for p35S targeting 81 bp of sequence was even more sensitive than that targeting 101 bp of sequence by a 3-log scale. The target DNA fragments were also specifically amplified from all GM labeled food samples except for one item we tested when 35F1-R1 primer set was applied. A reference plasmid pGMmaize (3 kb) including the smaller PCR products for p35S, tNOS, p35S-hsp70 intron, and the zSSIIb gene was constructed for real-time PCR (RT-PCR). The linearity of standard curves was confirmed by using diluents ranging from 2×10(1)~10(5) copies of pGMmaize and the R(2) values ranged from 0.999~1.000. In the RT-PCR, the detection limit using the novel primer/probe sets was 5 pg of genomic DNA from MON810 line indicating that the primer sets targeting the smaller regions (80 or 81 bp) could be used for highly sensitive detection of foreign DNA fragments from GM maize in processed foods.

  2. Establishment of Quantitative Analysis Method for Genetically Modified Maize Using a Reference Plasmid and Novel Primers

    PubMed Central

    Moon, Gi-Seong; Shin, Weon-Sun

    2012-01-01

    For the quantitative analysis of genetically modified (GM) maize in processed foods, primer sets and probes based on the 35S promoter (p35S), nopaline synthase terminator (tNOS), p35S-hsp70 intron, and zSSIIb gene encoding starch synthase II for intrinsic control were designed. Polymerase chain reaction (PCR) products (80~101 bp) were specifically amplified and the primer sets targeting the smaller regions (80 or 81 bp) were more sensitive than those targeting the larger regions (94 or 101 bp). Particularly, the primer set 35F1-R1 for p35S targeting 81 bp of sequence was even more sensitive than that targeting 101 bp of sequence by a 3-log scale. The target DNA fragments were also specifically amplified from all GM labeled food samples except for one item we tested when 35F1-R1 primer set was applied. A reference plasmid pGMmaize (3 kb) including the smaller PCR products for p35S, tNOS, p35S-hsp70 intron, and the zSSIIb gene was constructed for real-time PCR (RT-PCR). The linearity of standard curves was confirmed by using diluents ranging from 2×101~105 copies of pGMmaize and the R2 values ranged from 0.999~1.000. In the RT-PCR, the detection limit using the novel primer/probe sets was 5 pg of genomic DNA from MON810 line indicating that the primer sets targeting the smaller regions (80 or 81 bp) could be used for highly sensitive detection of foreign DNA fragments from GM maize in processed foods. PMID:24471096

  3. Comparison of two methods to transmit clinical history information from referring providers to radiologists.

    PubMed

    Agarwal, Rajan; Bleshman, Michael H; Langlotz, Curtis P

    2009-11-01

    need for better communication between referring providers and radiologists.

  4. Developing qualitative LC-MS methods for characterization of Vaccinium berry Standard Reference Materials.

    PubMed

    Lowenthal, Mark S; Phillips, Melissa M; Rimmer, Catherine A; Rudnick, Paul A; Simón-Manso, Yamil; Stein, Stephen E; Tchekhovskoi, Dmitrii; Phinney, Karen W

    2013-05-01

    Standard Reference Materials (SRMs) offer the scientific community a stable and homogenous source of material that holds countless application possibilities. Traditionally, the National Institute of Standards and Technology (NIST) has provided SRMs with associated quantitative information (certified values) for a select group of targeted analytes as measured in a solution or complex matrix. While the current needs of the SRM community are expanding to include non-quantitative data, NIST is attempting to broaden the scope of how and what information is offered to the SRM community by providing qualitative information about biomaterials, such as chromatographic fingerprints and profiles of untargeted identifications. In this work, metabolomic and proteomic profiling efforts were employed to characterize a suite of six Vaccinium berry SRMs. In the discovery phase, liquid chromatography-tandem mass spectrometry (LC-MS/MS) data was matched to mass spectral libraries; a subsequent validation phase based on multiple-reaction monitoring LC-MS/MS relied on both retention time matching of authentic standards along with fragmentation data for a qualitative overview of the most prominent organic compounds present. Definitive and putative identifications were determined for over 70 metabolites based on reporting guidelines set forth by the Metabolomics Standards Initiative (Metabolomics 3(3):211-221, 2007), and the capability of electrospray ionization mass spectrometry (ESI-MS) to profile untargeted metabolites within a complex matrix using mass spectral matching is demonstrated. Bottom-up proteomic analyses were possible using peptide databases translated from expressed sequence tags (ESTs). Homology searches provided identification of novel Vaccinium proteins based on homology to related genera. Chromatographic fingerprints of these berry materials were acquired for supplemental qualitative information to be provided to users of these SRMs. An unbounded set of qualitative

  5. A reference standard for evaluation of methods for drug safety signal detection using electronic healthcare record databases.

    PubMed

    Coloma, Preciosa M; Avillach, Paul; Salvo, Francesco; Schuemie, Martijn J; Ferrajolo, Carmen; Pariente, Antoine; Fourrier-Réglat, Annie; Molokhia, Mariam; Patadia, Vaishali; van der Lei, Johan; Sturkenboom, Miriam; Trifirò, Gianluca

    2013-01-01

    The growing interest in using electronic healthcare record (EHR) databases for drug safety surveillance has spurred development of new methodologies for signal detection. Although several drugs have been withdrawn postmarketing by regulatory authorities after scientific evaluation of harms and benefits, there is no definitive list of confirmed signals (i.e. list of all known adverse reactions and which drugs can cause them). As there is no true gold standard, prospective evaluation of signal detection methods remains a challenge. Within the context of methods development and evaluation in the EU-ADR Project (Exploring and Understanding Adverse Drug Reactions by integrative mining of clinical records and biomedical knowledge), we propose a surrogate reference standard of drug-adverse event associations based on existing scientific literature and expert opinion. The reference standard was constructed for ten top-ranked events judged as important in pharmacovigilance. A stepwise approach was employed to identify which, among a list of drug-event associations, are well recognized (known positive associations) or highly unlikely ('negative controls') based on MEDLINE-indexed publications, drug product labels, spontaneous reports made to the WHO's pharmacovigilance database, and expert opinion. Only drugs with adequate exposure in the EU-ADR database network (comprising ≈60 million person-years of healthcare data) to allow detection of an association were considered. Manual verification of positive associations and negative controls was independently performed by two experts proficient in clinical medicine, pharmacoepidemiology and pharmacovigilance. A third expert adjudicated equivocal cases and arbitrated any disagreement between evaluators. Overall, 94 drug-event associations comprised the reference standard, which included 44 positive associations and 50 negative controls for the ten events of interest: bullous eruptions; acute renal failure; anaphylactic shock

  6. Evaluation and Recalibration of Empirical Constant for Estimation of Reference Crop Evapotranspiration against the Modified Penman Method

    NASA Astrophysics Data System (ADS)

    Sasireka, K.; Jagan Mohan Reddy, C.; Charan Reddy, C.; Ramakrishnan, K.

    2017-07-01

    The major demand in our country is irrigation demand. Looking to the low irrigation potential and small water resources, it is felt necessary to see that water must be used economically and efficiently. This may be achieved by using latest methods of determination of water requirements for crops and applying the proper water management practices. Evapotranspiration (ET) is a basic for calculation of water requirement for crops. The various popular empirical equations for reference crop evapotranspiration (ETr) belong to three categories namely, Temperature, Radiation based methods and Combined methods. The above methods are site specific; hence it is necessary to recalibrate the coefficients for applying them in India. In the present paper, the standard combined method namely FAO modified Penman method was used to recalibrate the constants in temperature based (TB) methods and it can also be used to determine the ETr for the selected station. Four TB evapotranspiration models namely Blaney-Criddle, Romanenko, Kharrufa, and, Thronthwaite methods are recalibrated and the constant in each method are redefined for the data from Lekkur station, Cuddalore district in India. The result shows that, large error existed when ETr has been calculated with original constants. Hence regression equations were developed to minimise these variations in magnitude. It was found that out of four methods the Blaney-Criddle method suits better for the selected region.

  7. RAND’s Portfolio Analysis Tool (PAT): Theory, Methods, and Reference Manual

    DTIC Science & Technology

    2009-01-01

    1997), value-focused thinking (Keeney, 1992; Parnell, 2006), and balanced - scorecard methods used in business ( Kaplan and Norton , 1996). The original...Defense in the Nuclear Age, Cambridge, Mass.: Harvard University Press, 1965. Kaplan , Robert S., and David P. Norton , The Balanced Scorecard ...1 Strategic Planning and the Balancing of Investments

  8. Methods And Systems For Using Reference Images In Acoustic Image Processing

    DOEpatents

    Moore, Thomas L.; Barter, Robert Henry

    2005-01-04

    A method and system of examining tissue are provided in which a field, including at least a portion of the tissue and one or more registration fiducials, is insonified. Scattered acoustic information, including both transmitted and reflected waves, is received from the field. A representation of the field, including both the tissue and the registration fiducials, is then derived from the received acoustic radiation.

  9. 40 CFR 98.7 - What standardized methods are incorporated by reference into this part?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Liquid Hydrocarbon Fuels by Bomb Calorimeter, IBR approved for § 98.254(e). (5) ASTM D388-05 Standard... by Bomb Calorimeter (Precision Method), IBR approved for § 98.254(e). (25) ASTM D4891-89 (Reapproved... Coal, Coke, and Solid Residues from Combustion of Coal and Coke by Inductively Coupled Plasma—Atomic...

  10. [Comparison of diverse methods for the cultivation of anaerobians, with special reference to the GASPAK system].

    PubMed

    Wehrspann, P

    1976-01-01

    The frequent presence of anaerobic bacteria in clinical specimens requires the use of adequate methods for their detection. The GASPAK system, following closely the experiences made by BREWER, meets these requirements and has the additional advantage of easier handling when compared with other methods. Hydrogen necessary for binding oxygen in the anaerobe-receptacle, is produced chemically from a sodium borohydride plate over which only a certain amount of water needs to be poured for activation. A bar containing citric acid and sodium bicarbonate releases carbon dioxide at the same time. Small palladium-coated aluminium balls act as a cold catalyst. The hydrogen-carbon dioxide developer is supplied in disposable bags (Fig. 1). A strip impregnated with methylene blue is used as indicator. This strip is used only once. The GASPAK system was examined and compared with the anaerobe-receptacle by FILDES and MCINTOSH where a pressure-bottle feeds the hydrogen into the system, and the vacuum-process by ZEISSLER. Growth of several anaerobians from fresh clinical specimens and from some defined strains was used in the test (Table 1-4). The highest rate of growth was achieved with the GASPAK-system so that - even if one bears in mind that the other two methods do not undergo enrichment by carbon dioxide - this method for the cultivation of anaerobians can be recommended for use in routine laboratories.

  11. 75 FR 51039 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... new equivalent methods for measuring concentrations of PM 10 and sulfur dioxide (SO 2 ) in the ambient... concentrations of those ambient air pollutants for which EPA has established National Ambient Air Quality... measuring concentrations of PM 10 and SO 2 in the ambient air. These designations are made under the...

  12. 76 FR 15974 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-22

    ... new equivalent methods: One each for measuring concentrations of PM 2.5 and lead (Pb) and two for measuring concentrations of PM 10 in the ambient air. FOR FURTHER INFORMATION CONTACT: Robert Vanderpool... for monitoring the concentrations of those ambient air pollutants for which EPA has established...

  13. 75 FR 30022 - Office of Research and Development; Ambient Air Monitoring Reference and Equivalent Methods...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-28

    ... new equivalent method for measuring concentrations of lead (Pb) in total suspended particulate matter... monitoring the concentrations of those ambient air pollutants for which EPA has established National Ambient...-0510-191, ``Determination of Lead Concentration in TSP by Inductively Coupled Plasma Mass Spectrometry...

  14. Stochastic multi-reference perturbation theory with application to the linearized coupled cluster method

    NASA Astrophysics Data System (ADS)

    Jeanmairet, Guillaume; Sharma, Sandeep; Alavi, Ali

    2017-01-01

    In this article we report a stochastic evaluation of the recently proposed multireference linearized coupled cluster theory [S. Sharma and A. Alavi, J. Chem. Phys. 143, 102815 (2015)]. In this method, both the zeroth-order and first-order wavefunctions are sampled stochastically by propagating simultaneously two populations of signed walkers. The sampling of the zeroth-order wavefunction follows a set of stochastic processes identical to the one used in the full configuration interaction quantum Monte Carlo (FCIQMC) method. To sample the first-order wavefunction, the usual FCIQMC algorithm is augmented with a source term that spawns walkers in the sampled first-order wavefunction from the zeroth-order wavefunction. The second-order energy is also computed stochastically but requires no additional overhead outside of the added cost of sampling the first-order wavefunction. This fully stochastic method opens up the possibility of simultaneously treating large active spaces to account for static correlation and recovering the dynamical correlation using perturbation theory. The method is used to study a few benchmark systems including the carbon dimer and aromatic molecules. We have computed the singlet-triplet gaps of benzene and m-xylylene. For m-xylylene, which has proved difficult for standard complete active space self consistent field theory with perturbative correction, we find the singlet-triplet gap to be in good agreement with the experimental values.

  15. A Study on Simulation Methods in Academic Success with Reference to Teaching Biology for Education Students

    ERIC Educational Resources Information Center

    Sasikala, P.; Tanyong, Siriwan

    2016-01-01

    The main objective of this study is to determine the utility of simulation methods in biology teaching for nursing students and academic success. 100 students (50 control, 50 experimental) who studied at Srinivasa Teacher Training School, Kalikiri, Recognised by Sri Venkateswara University, Faculty of Education, Tirupati, AP, India, 2014-215…

  16. 40 CFR 53.4 - Applications for reference or equivalent method determinations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Required or recommended routine, periodic, and preventative maintenance and maintenance schedules. (J) Any... methods for PM2.5 and PM10−2.5 must be described in sufficient detail, based on the elements described in... Table A-1 to this subpart) will be met throughout the warranty period and that the applicant accepts...

  17. 40 CFR 53.4 - Applications for reference or equivalent method determinations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Required or recommended routine, periodic, and preventative maintenance and maintenance schedules. (J) Any... methods for PM2.5 and PM10−2.5 must be described in sufficient detail, based on the elements described in... Table A-1 to this subpart) will be met throughout the warranty period and that the applicant accepts...

  18. Review of statistical methods used in enhanced-oil-recovery research and performance prediction. [131 references

    SciTech Connect

    Selvidge, J.E.

    1982-06-01

    Recent literature in the field of enhanced oil recovery (EOR) was surveyed to determine the extent to which researchers in EOR take advantage of statistical techniques in analyzing their data. In addition to determining the current level of reliance on statistical tools, another objective of this study is to promote by example the greater use of these tools. To serve this objective, the discussion of the techniques highlights the observed trend toward the use of increasingly more sophisticated methods and points out the strengths and pitfalls of different approaches. Several examples are also given of opportunities for extending EOR research findings by additional statistical manipulation. The search of the EOR literature, conducted mainly through computerized data bases, yielded nearly 200 articles containing mathematical analysis of the research. Of these, 21 were found to include examples of statistical approaches to data analysis and are discussed in detail in this review. The use of statistical techniques, as might be expected from their general purpose nature, extends across nearly all types of EOR research covering thermal methods of recovery, miscible processes, and micellar polymer floods. Data come from field tests, the laboratory, and computer simulation. The statistical methods range from simple comparisons of mean values to multiple non-linear regression equations and to probabilistic decision functions. The methods are applied to both engineering and economic data. The results of the survey are grouped by statistical technique and include brief descriptions of each of the 21 relevant papers. Complete abstracts of the papers are included in the bibliography. Brief bibliographic information (without abstracts) is also given for the articles identified in the initial search as containing mathematical analyses using other than statistical methods.

  19. Method of planning a reference trajectory of a single lane change manoeuver with Bezier curve

    NASA Astrophysics Data System (ADS)

    Korzeniowski, D.; Ślaski, G.

    2016-09-01

    For a comprehensive simulation of vehicle steering process it is vital to model the decision process of planning a trajectory shape and process of the selected trajectory. A single lane change manoeuver is only slightly restricted by the road geometry. There are also other requirements of a possible trajectory of movement, such as the continuity of change (derivative) of curvature, maximizing the passenger's comfort measured with appropriate indicators based on variables of motion dynamics or parameters of motion trajectory which influence that dynamic. This article presents a suggested method of automatic generation of trajectory of single lane change manoeuver. The proposed method can be used as an integral part of driver models and is based on a combination of two symmetrical Bezier curves optionally supplemented with a straight lane connector. The method meets the requirements of a trajectory shape, which results from optimizing the value of parameters controlling Bezier curve based on minimizing the curvature and the resulting lateral acceleration while preserving the continuity of curvature derivative of the planned trajectory.

  20. 40 CFR Appendix A to Part 50 - Reference Method for the Determination of Sulfur Dioxide in the Atmosphere (Pararosaniline Method)

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to minimize losses during this period. Thermoelectric coolers specifically designed for this... temporary level mark on the absorber. If either the temperature is above 10 °C or there was significant loss... Correlation Coefficient. The method of least squares is used to calculate a calibration equation in the form...

  1. Optimizing testing methods and collection of reference data for differentiating critical illness polyneuropathy from critical illness MYOPATHIES.

    PubMed

    Marrero, Humberto Gonzalez; Stålberg, Erik V

    2016-04-01

    In severe acute quadriplegic myopathy in intensive care unit (ICU) patients, muscle fibers are electrically inexcitable; in critical illness polyneuropathy, the excitability remains normal. Conventional electrodiagnostic methods do not provide the means to adequately differentiate between them. In this study we aimed to further optimize the methodology for the study of critically ill ICU patients and to create a reference database in healthy controls. Different electrophysiologic protocols were tested to find sufficiently robust and reproducible techniques for clinical diagnostic applications. Many parameters show large test-retest variability within the same healthy subject. Reference values have been collected and described as a basis for studies of weakness in critical illness. Using the ratio of neCMAP/dmCMAP (response from nerve and direct muscle stimulation), refractory period, and stimulus-response curves may optimize the electrodiagnostic differentiation of patients with critical illness myopathy from those with critical illness polyneuropathy. © 2015 Wiley Periodicals, Inc.

  2. An improved way of minimizing free energy in the variational method with the square well reference system

    NASA Astrophysics Data System (ADS)

    Dubinin, N. E.; Filippov, V. V.; Yuryev, A. A.; Vatolin, N. A.

    2017-05-01

    For the variational method of the thermodynamic perturbation theory with the square well reference system to which the semianalytical way of solving the mean spherical approximation is applied, a new way of minimizing the free energy is proposed. The approach is applied to liquid sodium and potassium, the effective pair interaction in which is described within the framework of the pseudopotential theory. For each of the metals under study, the global minimum of the free energy was found as a function of two independent variables (the hard core diameter and the mean atomic volume). In this minimum, a better agreement between the calculation results and the experimental data is obtained than when using the hard sphere reference system.

  3. Agency for Healthcare Research and Quality Evidence-based Practice Center methods for systematically reviewing complex multicomponent health care interventions.

    PubMed

    Guise, Jeanne-Marie; Chang, Christine; Viswanathan, Meera; Glick, Susan; Treadwell, Jonathan; Umscheid, Craig A; Whitlock, Evelyn; Fu, Rongwei; Berliner, Elise; Paynter, Robin; Anderson, Johanna; Motu'apuaka, Pua; Trikalinos, Tom

    2014-11-01

    The purpose of this Agency for Healthcare Research and Quality Evidence-based Practice Center methods white paper was to outline approaches to conducting systematic reviews of complex multicomponent health care interventions. We performed a literature scan and conducted semistructured interviews with international experts who conduct research or systematic reviews of complex multicomponent interventions (CMCIs) or organizational leaders who implement CMCIs in health care. Challenges identified include lack of consistent terminology for such interventions (eg, complex, multicomponent, multidimensional, multifactorial); a wide range of approaches used to frame the review, from grouping interventions by common features to using more theoretical approaches; decisions regarding whether and how to quantitatively analyze the interventions, from holistic to individual component analytic approaches; and incomplete and inconsistent reporting of elements critical to understanding the success and impact of multicomponent interventions, such as methods used for implementation the context in which interventions are implemented. We provide a framework for the spectrum of conceptual and analytic approaches to synthesizing studies of multicomponent interventions and an initial list of critical reporting elements for such studies. This information is intended to help systematic reviewers understand the options and tradeoffs available for such reviews. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Sex- and Method-Specific Reference Values for Right Ventricular Strain by 2-Dimensional Speckle-Tracking Echocardiography.

    PubMed

    Muraru, Denisa; Onciul, Sebastian; Peluso, Diletta; Soriani, Nicola; Cucchini, Umberto; Aruta, Patrizia; Romeo, Gabriella; Cavalli, Giacomo; Iliceto, Sabino; Badano, Luigi P

    2016-02-01

    Despite the fact that assessment of right ventricular longitudinal strain (RVLS) carries important implications for patient diagnosis, prognosis, and treatment, its implementation in clinical settings has been hampered by the limited reference values and the lack of uniformity in software, method, and definition used for measuring RVLS. Accordingly, this study was designed to establish (1) the reference values for RVLS by 2-dimensional speckle-tracking echocardiography; and (2) their relationship with demographic, hemodynamic, and cardiac factors. In 276 healthy volunteers (55% women; age, 18-76 years), free wall and septum RVLS (6 segments) and free wall RVLS (3 segments) using both 6- and 3-segment regions of interest were obtained. Feasibility of 6-segment RVLS was 92%. Free wall RVLS from 3- versus 6-segment regions of interest had similar values, yet 6-segment region of interest was more feasible (86% versus 73%; P<0.001) and reproducible. Reference values (lower limits of normality) were as follows: 6-segment RVLS, -24.7±2.6% (-20.0%) for men and -26.7±3.1% (-20.3%) for women; 3-segment RVLS, -29.3±3.4% (-22.5%) for men and -31.6±4.0% (-23.3%) for women (P<0.001). Free wall RVLS was 5±2 strain units (%) larger in magnitude than 6-segment RVLS, 10±4% larger than septal RVLS, and 2±4% larger in women than in men (P<0.001). At multivariable analysis, age, sex, pulmonary systolic pressure, right atrial minimal volume, as well as right atrial and left ventricular longitudinal strain resulted as correlates of RVLS values. This is the largest study providing sex- and method-specific reference values for RVLS. Our data may foster the implementation of 2-dimensional speckle-tracking echocardiography-derived RV analysis in clinical practice. © 2016 American Heart Association, Inc.

  5. A Reference Broth Microdilution Method for Dalbavancin In Vitro Susceptibility Testing of Bacteria that Grow Aerobically.

    PubMed

    Koeth, Laura M; DiFranco-Fisher, Jeanna M; McCurdy, Sandra

    2015-09-09

    Antimicrobial susceptibility testing (AST) is performed to assess the in vitro activity of antimicrobial agents against various bacteria. The AST results, which are expressed as minimum inhibitory concentrations (MICs) are used in research for antimicrobial development and monitoring of resistance development and in the clinical setting for antimicrobial therapy guidance. Dalbavancin is a semi-synthetic lipoglycopeptide antimicrobial agent that was approved in May 2014 by the Food and Drug Administration (FDA) for the treatment of acute bacterial skin and skin structure infections caused by Gram-positive organisms. The advantage of dalbavancin over current anti-staphylococcal therapies is its long half-life, which allows for once-weekly dosing. Dalbavancin has activity against Staphylococcus aureus (including both methicillin-susceptible S. aureus [MSSA] and methicillin-resistant S. aureus [MRSA]), coagulase-negative staphylococci, Streptococcus pneumoniae, Streptococcus anginosus group, β-hemolytic streptococci and vancomycin susceptible enterococci. Similar to other recent lipoglycopeptide agents, optimization of CLSI and ISO broth susceptibility test methods includes the use of dimethyl sulfoxide (DMSO) as a solvent when preparing stock solutions and polysorbate 80 (P80) to alleviate adherence of the agent to plastic. Prior to the clinical studies and during the initial development of dalbavancin, susceptibility studies were not performed with the use of P-80 and MIC results tended to be 2-4 fold higher and similarly higher MIC results were obtained with the agar dilution susceptibility method. Dalbavancin was first included in CLSI broth microdilution methodology tables in 2005 and amended in 2006 to clarify use of DMSO and P-80. The broth microdilution (BMD) procedure shown here is specific to dalbavancin and is in accordance with the CLSI and ISO methods, with step-by-step detail and focus on the critical steps added for clarity.

  6. An automatic method for measurement of vertebral bone density based on QCT without an external reference phantom

    NASA Astrophysics Data System (ADS)

    Zhao, Kai; Pan, Xiao-guang; Zou, Yu-yue; Wang, Zhi-qiong; Zhang, Tian-jing; Shao, Kai; Kang, Yan; Zhao, Hong

    2009-10-01

    Purpose: We developed an automatic method for measurement of vertebral bone density based on QCT with the use of internal references(muscle and subcutaneous fat) instead of traditional external phantom. Methods: The automatic multistep approach starts with segmentation of periosteal and endosteal surfaces of spine to define ellipse ROI in cancellous bone followed by segmentation of muscle and subcutaneous fat in the spine image and a subsequent calculation of bone mineral density in ellipse ROI and segmentation trabecular and cortical bone ROI using muscle and subcutaneous fat as internal references. The segmentation approach used a hybrid region-growing method which used local adaptive threshold and morphological operation. Results: We conducted with-phantom and without-phantom measurements by using 94 clinical cases. The doctor manually defined the ellipse ROI in the with-phantom measurement. As for the without-phantom measurement, we use our method to automatically gain the BMD. The Interaclass Correlation Coefficient (ICC) is 0.93. We removed the points whose muscle and fat values are 2 times deviated from the standard deviation. And the calibrated ICC value is 0.999. Conclusion: The without-phantom measurement method is not fit for the patients whose muscle and fat are seriously deviated from the average value. The without-phantom measurement method proposed in this paper can automatically measure the BMD of spine. By accurately segmenting cortical bone and trabecular bone, determining ROI and removing inappropriate data, it is proved that the BMD measurement result by this method is highly consistent with that by with-phantom method.

  7. A Rapid Identification Method for Calamine Using Near-Infrared Spectroscopy Based on Multi-Reference Correlation Coefficient Method and Back Propagation Artificial Neural Network.

    PubMed

    Sun, Yangbo; Chen, Long; Huang, Bisheng; Chen, Keli

    2017-07-01

    As a mineral, the traditional Chinese medicine calamine has a similar shape to many other minerals. Investigations of commercially available calamine samples have shown that there are many fake and inferior calamine goods sold on the market. The conventional identification method for calamine is complicated, therefore as a result of the large scale of calamine samples, a rapid identification method is needed. To establish a qualitative model using near-infrared (NIR) spectroscopy for rapid identification of various calamine samples, large quantities of calamine samples including crude products, counterfeits and processed products were collected and correctly identified using the physicochemical and powder X-ray diffraction method. The NIR spectroscopy method was used to analyze these samples by combining the multi-reference correlation coefficient (MRCC) method and the error back propagation artificial neural network algorithm (BP-ANN), so as to realize the qualitative identification of calamine samples. The accuracy rate of the model based on NIR and MRCC methods was 85%; in addition, the model, which took comprehensive multiple factors into consideration, can be used to identify crude calamine products, its counterfeits and processed products. Furthermore, by in-putting the correlation coefficients of multiple references as the spectral feature data of samples into BP-ANN, a BP-ANN model of qualitative identification was established, of which the accuracy rate was increased to 95%. The MRCC method can be used as a NIR-based method in the process of BP-ANN modeling.

  8. A reference method for the evaluation of femoral head joint center location technique based on external markers.

    PubMed

    Pillet, Hélène; Sangeux, Morgan; Hausselle, Jérôme; El Rachkidi, Rami; Skalli, Wafa

    2014-01-01

    Accurate localization of joint centers is essential in movement analysis. However, joint centers cannot be directly palpated and alternative methods must be used. To assess the relative merits of these methods, a medical image based reference should be used. The EOS(®) system, a new low dose bi-planar X-rays imaging technique may be considered. The aim of this study was to evaluate the accuracy of hip joint center (HJC) localization using the EOS(®) system. Seventeen healthy young adults participated in the study. Femoral heads and pelvic external markers were localized using the EOS(®) system and the HJCs were expressed in the movement analysis coordinate system. Results showed that external marker localization was reliable within 0.15 mm for trained assessors. Mean accuracy for HJC localization was 2.9 mm (SD: 1.3, max: 6.2). The EOS based method therefore appeared reliable and may be used for femoral head localization or as a reference to assess the accuracy of other methods for HJC localization.

  9. Retrieval of diffusing surface by two-frame interferometric method with blind phase shift of a reference wave

    NASA Astrophysics Data System (ADS)

    Muravsky, Leonid I.; Kmet', Arkady B.; Voronyak, Taras I.

    2011-08-01

    Two-frame interferometric method with blind phase shift of a reference wave for smooth surfaces retrieval is considered. The ability of this method to reconstruct a macrorelief of diffusing surfaces with a given roughness is studied. Computer simulations have testified the ability of reliable low-noise reconstruction of the diffusing surface macrorelief with standard deviation of the roughness heights up to λ/10 by using the developed interferogram processing algorithm. The simulations have shown that the proposed correlation approach, which is used to determine the reference wave blind phase shift, is more suitable for a diffusing surface than for a smooth one and the increase of surface roughness leads to a quadruple decrease of this error in comparison with that for the smooth surface. Experimental verification of the interferometric method performance to retrieve real diffusing surface macroreliefs with given roughness has been done by using the experimental setup based on a Twyman-Green interferometer and roughness comparison specimen. The obtained experimental results virtually have coincided with the computer simulation results that prove the performance of the considered method to retrieve not only smooth, but also diffusing surfaces.

  10. Perturbative universal state-selective correction for state-specific multi-reference coupled cluster methods

    NASA Astrophysics Data System (ADS)

    Brabec, Jiri; Banik, Subrata; Kowalski, Karol; Pittner, Jiří

    2016-10-01

    In this work, we report an extension of our previous development of the universal state-selective (USS) multireference coupled-cluster (MRCC) formalism. It was shown [Brabec et al., J. Chem. Phys. 136, 124102 (2012)] and [Banik et al., J. Chem. Phys. 142, 114106 (2015)] that the USS(2) approach significantly improves the accuracy of Brillouin-Wigner and Mukherjee MRCC formulations, however, the numerical and storage costs associated with calculating highly excited intermediates pose a significant challenge, which can restrict the applicability of the USS(2) method. Therefore, we introduce a perturbative variant of the USS(2) approach (USS(pt)), which substantially reduces numerical overhead of the full USS(2) correction while preserving its accuracy. Since the new USS(pt) implementation calculates the triple and quadruple projections in on-the-fly manner, the memory bottleneck associated with the need of storing expensive recursive intermediates is entirely eliminated. On the example of several benchmark systems, we demonstrate accuracies of USS(pt) and USS(2) approaches and their efficiency in describing quasidegenerate electronic states. It is also shown that the USS(pt) method significantly alleviates problems associated with the lack of invariance of MRCC theories upon the rotation of active orbitals.

  11. Reliability of Different Mark-Recapture Methods for Population Size Estimation Tested against Reference Population Sizes Constructed from Field Data

    PubMed Central

    Grimm, Annegret; Gruber, Bernd; Henle, Klaus

    2014-01-01

    Reliable estimates of population size are fundamental in many ecological studies and biodiversity conservation. Selecting appropriate methods to estimate abundance is often very difficult, especially if data are scarce. Most studies concerning the reliability of different estimators used simulation data based on assumptions about capture variability that do not necessarily reflect conditions in natural populations. Here, we used data from an intensively studied closed population of the arboreal gecko Gehyra variegata to construct reference population sizes for assessing twelve different population size estimators in terms of bias, precision, accuracy, and their 95%-confidence intervals. Two of the reference populations reflect natural biological entities, whereas the other reference populations reflect artificial subsets of the population. Since individual heterogeneity was assumed, we tested modifications of the Lincoln-Petersen estimator, a set of models in programs MARK and CARE-2, and a truncated geometric distribution. Ranking of methods was similar across criteria. Models accounting for individual heterogeneity performed best in all assessment criteria. For populations from heterogeneous habitats without obvious covariates explaining individual heterogeneity, we recommend using the moment estimator or the interpolated jackknife estimator (both implemented in CAPTURE/MARK). If data for capture frequencies are substantial, we recommend the sample coverage or the estimating equation (both models implemented in CARE-2). Depending on the distribution of catchabilities, our proposed multiple Lincoln-Petersen and a truncated geometric distribution obtained comparably good results. The former usually resulted in a minimum population size and the latter can be recommended when there is a long tail of low capture probabilities. Models with covariates and mixture models performed poorly. Our approach identified suitable methods and extended options to evaluate the

  12. Investigation on the Reference Evapotranspiration Distribution at Regional Scale By Alternative Methods to Compute the FAO Penman-Monteith Equation

    NASA Astrophysics Data System (ADS)

    Snyder, R. L.; Mancosu, N.; Spano, D.

    2014-12-01

    This study derived the summer (June-August) reference evapotranspiration distribution map for Sardinia (Italy) based on weather station data and use of the geographic information system (GIS). A modified daily Penman-Monteith equation from the Food and Agriculture Organization of the United Nations (UN-FAO) and the American Society of Civil Engineers Environmental and Water Resources Institute (ASCE-EWRI) was used to calculate the Standardized Reference Evapotranspiration (ETos) for all weather stations having a "full" set of required data for the calculations. For stations having only temperature data (partial stations), the Hargreaves-Samani equation was used to estimate the reference evapotranspiration for a grass surface (ETo). The ETos and ETo results were different depending on the local climate, so two methods to estimate ETos from the ETo were tested. Substitution of missing solar radiation, wind speed, and humidity data from a nearby station within a similar microclimate was found to give better results than using a calibration factor that related ETos and ETo. Therefore, the substitution method was used to estimate ETos at "partial" stations having only temperature data. The combination of 63 full and partial stations was sufficient to use GIS to map ETos for Sardinia. Three interpolation methods were studied, and the ordinary kriging model fitted the observed data better than a radial basis function or the inverse distance weighting method. Using station data points to create a regional map simplified the zonation of ETos when large scale computations were needed. Making a distinction based on ETos classes allows the simulation of crop water requirements for large areas and it can potentially lead to improved irrigation management and water savings. It also provides a baseline to investigate possible impact of climate change.

  13. Identification of particle size classes inhibiting protozoan recovery from surface water samples via U.S. Environmental Protection Agency method 1623.

    PubMed

    Krometis, Leigh-Anne H; Characklis, Gregory W; Sobsey, Mark D

    2009-10-01

    Giardia species recovery by U.S. Environmental Protection Agency method 1,623 appears significantly impacted by a wide size range (2 to 30 microm) of particles in water and organic matter. Cryptosporidium species recovery seems negatively correlated only with smaller (2 to 10 microm), presumably inorganic particles. Results suggest constituents and mechanisms interfering with method performance may differ by protozoan type.

  14. Substantiation of Reference Method For Determining Concrete’s Freeze-Thaw Resistance

    NASA Astrophysics Data System (ADS)

    Nikolskiy, S.; Pertseva, O.

    2017-01-01

    It has been analytically proved that using concrete’s rate of set ε as a measure of damage, instead of decreasing of tensile strength R, increases freeze-thaw resistance’s accuracy of estimation a lot under otherwise equal conditions by the time of freeze-thaw cycling. Also it has been experimentally shown that ratio of relative decreasing R to ε in direction, perpendicular to compression, is assumed to be independent on values R and ε for a given concrete and on the ways of achieving them during mechanical or freeze-thaw cycling. Taking this into account patented methods for estimation of concrete’s freeze-thaw resistance as per values R and ε received after freezing and thawing cycles of some specimens and their postliminary failure by linear compression was substantiated.

  15. A new reference method for the determination of the oxygen content of blood.

    PubMed

    Dijkhuizen, P; Kwant, G; Zijlstra, W G

    1976-04-01

    To be able to determine the slight differences between the theoretical and the actual O2-binding capacity of human haemoglobin, a highly accurate method has been developed for measuring the O2 content of blood samples. It is an adaptation of an established O2 determination in organic microanalysis. The bound O2 of the blood is set free by conversion of HbO2 to Hi, and the O2 stripped from the blood is converted to CO by contact with granular carbon at 1120 degrees C. The CO is then converted to CO2 using CuO at 300 degrees C and the CO2 titrated in a solution of BaCl2, using NaOH of known strength. The measuring system was checked by analysis of 36 samples of air, yielding an O2 content of 20.93 +/- 0.06%. The coefficient of variation calculated from 62 duplicate determinations of samples of human blood was 0.65%.

  16. Perturbational treatment of spin-orbit coupling for generally applicable high-level multi-reference methods

    SciTech Connect

    Mai, Sebastian; Marquetand, Philipp; González, Leticia; Müller, Thomas; Plasser, Felix; Lischka, Hans

    2014-08-21

    An efficient perturbational treatment of spin-orbit coupling within the framework of high-level multi-reference techniques has been implemented in the most recent version of the COLUMBUS quantum chemistry package, extending the existing fully variational two-component (2c) multi-reference configuration interaction singles and doubles (MRCISD) method. The proposed scheme follows related implementations of quasi-degenerate perturbation theory (QDPT) model space techniques. Our model space is built either from uncontracted, large-scale scalar relativistic MRCISD wavefunctions or based on the scalar-relativistic solutions of the linear-response-theory-based multi-configurational averaged quadratic coupled cluster method (LRT-MRAQCC). The latter approach allows for a consistent, approximatively size-consistent and size-extensive treatment of spin-orbit coupling. The approach is described in detail and compared to a number of related techniques. The inherent accuracy of the QDPT approach is validated by comparing cuts of the potential energy surfaces of acrolein and its S, Se, and Te analoga with the corresponding data obtained from matching fully variational spin-orbit MRCISD calculations. The conceptual availability of approximate analytic gradients with respect to geometrical displacements is an attractive feature of the 2c-QDPT-MRCISD and 2c-QDPT-LRT-MRAQCC methods for structure optimization and ab inito molecular dynamics simulations.

  17. Characterization of the Aerosol-based Synthesis of Uranium Particles as a Potential Reference Material for Micro Analytical Methods.

    PubMed

    Middendorp, Ronald; Dürr, Martin; Knott, Alexander; Pointurier, Fabien; Ferreira Sanchez, Dario; Samson, Valerie Ann; Grolimund, Daniel

    2017-03-27

    A process for production of micrometer-sized particles composed of uranium oxide using aerosol spray pyrolysis is characterized with respect to the various production parameters. The aerosol is generated using a vibrating orifice aerosol generator providing monodisperse droplets, which are oxidized in a subsequent heat treatment. The final particles are characterized with micro analytical methods to determine size, shape, internal morphology, chemical and structural properties in order to assess the suitability of the produced particles as a reference material for micro analytical methods, in particular for mass-spectrometry. It is demonstrated that physico-chemical processes during particle formation and the heat treatment to chemically transform particles into an oxide strongly influence the particle shape and the internal morphology. Synchrotron μ-X-ray based techniques combined with μ-Raman spectroscopy have been applied to demonstrate that the obtained micro particles consist of a triuranium octoxide phase. Our studies demonstrate that the process is capable of delivering spherical particles with determined uniform size and ele-mental as well as chemical composition. The particles therefore represent a suitable base material to fulfill the homogeneity and stability requirements of a reference material for micro analytical methods applied in, for example, international safeguards or nuclear forensics.

  18. Perturbational treatment of spin-orbit coupling for generally applicable high-level multi-reference methods.

    PubMed

    Mai, Sebastian; Müller, Thomas; Plasser, Felix; Marquetand, Philipp; Lischka, Hans; González, Leticia

    2014-08-21

    An efficient perturbational treatment of spin-orbit coupling within the framework of high-level multi-reference techniques has been implemented in the most recent version of the Columbus quantum chemistry package, extending the existing fully variational two-component (2c) multi-reference configuration interaction singles and doubles (MRCISD) method. The proposed scheme follows related implementations of quasi-degenerate perturbation theory (QDPT) model space techniques. Our model space is built either from uncontracted, large-scale scalar relativistic MRCISD wavefunctions or based on the scalar-relativistic solutions of the linear-response-theory-based multi-configurational averaged quadratic coupled cluster method (LRT-MRAQCC). The latter approach allows for a consistent, approximatively size-consistent and size-extensive treatment of spin-orbit coupling. The approach is described in detail and compared to a number of related techniques. The inherent accuracy of the QDPT approach is validated by comparing cuts of the potential energy surfaces of acrolein and its S, Se, and Te analoga with the corresponding data obtained from matching fully variational spin-orbit MRCISD calculations. The conceptual availability of approximate analytic gradients with respect to geometrical displacements is an attractive feature of the 2c-QDPT-MRCISD and 2c-QDPT-LRT-MRAQCC methods for structure optimization and ab inito molecular dynamics simulations.

  19. Floating reference position-based correction method for near-infrared spectroscopy in long-term glucose concentration monitoring

    NASA Astrophysics Data System (ADS)

    Han, Guang; Han, Tongshuai; Xu, Kexin; Liu, Jin

    2017-07-01

    We present a floating reference position (FRP)-based drift correction method for near-infrared (NIR) spectroscopy-based long-term blood glucose concentration (BGC) monitoring. Previously, we reported that it is difficult to quantify the systematic drift caused by the fluctuation of incident light intensity at different source-detector (SD) separations based on the absolute FRP change. We use the relative FRP change as a baseline reference to quantitatively characterize the signal drift at different SD separations. For the wavelengths that were used, a uniform equation was developed to describe the relationship between the drift and the relative FRP change. With the help of this equation, the correction can easily be performed by subtracting the systematic drift estimated by the equation. A theoretical analysis and an experimental phantom study demonstrated that our method could be used for systematic drift correction in NIR spectroscopy for long-term BGC monitoring. Moreover, the analysis method can also be referenced to reduce drifts from multiple sources.

  20. Reference scenarios for deforestation and forest degradation in support of REDD: a review of data and methods

    NASA Astrophysics Data System (ADS)

    Olander, Lydia P.; Gibbs, Holly K.; Steininger, Marc; Swenson, Jennifer J.; Murray, Brian C.

    2008-04-01

    Global climate policy initiatives are now being proposed to compensate tropical forest nations for reducing carbon emissions from deforestation and forest degradation (REDD). These proposals have the potential to include developing countries more actively in international greenhouse gas mitigation and to address a substantial share of the world's emissions which come from tropical deforestation. For such a policy to be viable it must have a credible benchmark against which emissions reduction can be calculated. This benchmark, sometimes termed a baseline or reference emissions scenario, can be based directly on historical emissions or can use historical emissions as input for business as usual projections. Here, we review existing data and methods that could be used to measure historical deforestation and forest degradation reference scenarios including FAO (Food and Agricultural Organization of the United Nations) national statistics and various remote sensing sources. The freely available and corrected global Landsat imagery for 1990, 2000 and soon to come for 2005 may be the best primary data source for most developing countries with other coarser resolution high frequency or radar data as a valuable complement for addressing problems with cloud cover and for distinguishing larger scale degradation. While sampling of imagery has been effectively useful for pan-tropical and continental estimates of deforestation, wall-to-wall (or full coverage) allows more detailed assessments for measuring national-level reference emissions. It is possible to measure historical deforestation with sufficient certainty for determining reference emissions, but there must be continued calls at the international level for making high-resolution imagery available, and for financial and technical assistance to help countries determine credible reference scenarios. The data available for past years may not be sufficient for assessing all forms of forest degradation, but new data sources

  1. Efficient and accurate local single reference correlation methods for high-spin open-shell molecules using pair natural orbitals

    NASA Astrophysics Data System (ADS)

    Hansen, Andreas; Liakos, Dimitrios G.; Neese, Frank

    2011-12-01

    A production level implementation of the high-spin open-shell (spin unrestricted) single reference coupled pair, quadratic configuration interaction and coupled cluster methods with up to doubly excited determinants in the framework of the local pair natural orbital (LPNO) concept is reported. This work is an extension of the closed-shell LPNO methods developed earlier [F. Neese, F. Wennmohs, and A. Hansen, J. Chem. Phys. 130, 114108 (2009), 10.1063/1.3086717; F. Neese, A. Hansen, and D. G. Liakos, J. Chem. Phys. 131, 064103 (2009), 10.1063/1.3173827]. The internal space is spanned by localized orbitals, while the external space for each electron pair is represented by a truncated PNO expansion. The laborious integral transformation associated with the large number of PNOs becomes feasible through the extensive use of density fitting (resolution of the identity (RI)) techniques. Technical complications arising for the open-shell case and the use of quasi-restricted orbitals for the construction of the reference determinant are discussed in detail. As in the closed-shell case, only three cutoff parameters control the average number of PNOs per electron pair, the size of the significant pair list, and the number of contributing auxiliary basis functions per PNO. The chosen threshold default values ensure robustness and the results of the parent canonical methods are reproduced to high accuracy. Comprehensive numerical tests on absolute and relative energies as well as timings consistently show that the outstanding performance of the LPNO methods carries over to the open-shell case with minor modifications. Finally, hyperfine couplings calculated with the variational LPNO-CEPA/1 method, for which a well-defined expectation value type density exists, indicate the great potential of the LPNO approach for the efficient calculation of molecular properties.

  2. Inspection methods for physical protection Task III review of other agencies' physical security activities for research reactors

    SciTech Connect

    1980-01-01

    In Task I of this project, the current Nuclear Regulatory Commission (NRC) position-on physical security practices and procedures at research reactors were reviewed. In the second task, a sampling of the physical security plans was presented and the three actual reactor sites described in the security plans were visited. The purpose of Task III is to review other agencies' physical security activities for research reactors. During this phase, the actions, procedures and policies of two domestic and two foreign agencies other than the NRC that relate to the research reactor community were examined. The agencies examined were: International Atomic Energy Agency; Canadian Atomic Energy Control Board; Department of Energy; and American Nuclear Insurers.

  3. Utility of Penman-Monteith, Priestley-Taylor, reference evapotranspiration, and pan evaporation methods to estimate pasture evapotranspiration

    USGS Publications Warehouse

    Sumner, D.M.; Jacobs, J.M.

    2005-01-01

    Actual evapotranspiration (ETa) was measured at 30-min resolution over a 19-month period (September 28, 2000-April 23, 2002) from a nonirrigated pasture site in Florida, USA, using eddy correlation methods. The relative magnitude of measured ETa (about 66% of long-term annual precipitation at the study site) indicates the importance of accurate ET a estimates for water resources planning. The time and cost associated with direct measurements of ETa and the rarity of historical measurements of ETa make the use of methods relying on more easily obtainable data desirable. Several such methods (Penman-Monteith (PM), modified Priestley-Taylor (PT), reference evapotranspiration (ET 0), and pan evaporation (Ep)) were related to measured ETa using regression methods to estimate PM bulk surface conductance, PT ??, ET0 vegetation coefficient, and Ep pan coefficient. The PT method, where the PT ?? is a function of green-leaf area index (LAI) and solar radiation, provided the best relation with ET a (standard error (SE) for daily ETa of 0.11 mm). The PM method, in which the bulk surface conductance was a function of net radiation and vapor-pressure deficit, was slightly less effective (SE=0.15 mm) than the PT method. Vegetation coefficients for the ET0 method (SE=0.29 mm) were found to be a simple function of LAI. Pan coefficients for the Ep method (SE=0.40 mm) were found to be a function of LAI and Ep. Historical or future meteorological, LAI, and pan evaporation data from the study site could be used, along with the relations developed within this study, to provide estimates of ETa in the absence of direct measurements of ETa. Additionally, relations among PM, PT, and ET0 methods and ETa can provide estimates of ETa in other, environmentally similar, pasture settings for which meteorological and LAI data can be obtained or estimated. ?? 2004 Elsevier B.V. All rights reserved.

  4. A method for the development of disease-specific reference standards vocabularies from textual biomedical literature resources

    PubMed Central

    Wang, Liqin; Bray, Bruce E.; Shi, Jianlin; Fiol, Guilherme Del; Haug, Peter J.

    2017-01-01

    Objective Disease-specific vocabularies are fundamental to many knowledge-based intelligent systems and applications like text annotation, cohort selection, disease diagnostic modeling, and therapy recommendation. Reference standards are critical in the development and validation of automated methods for disease-specific vocabularies. The goal of the present study is to design and test a generalizable method for the development of vocabulary reference standards from expert-curated, disease-specific biomedical literature resources. Methods We formed disease-specific corpora from literature resources like textbooks, evidence-based synthesized online sources, clinical practice guidelines, and journal articles. Medical experts annotated and adjudicated disease-specific terms in four classes (i.e., causes or risk factors, signs or symptoms, diagnostic tests or results, and treatment). Annotations were mapped to UMLS concepts. We assessed source variation, the contribution of each source to build disease-specific vocabularies, the saturation of the vocabularies with respect to the number of used sources, and the generalizability of the method with different diseases. Results The study resulted in 2588 string-unique annotations for heart failure in four classes, and 193 and 425 respectively for pulmonary embolism and rheumatoid arthritis in treatment class. Approximately 80% of the annotations were mapped to UMLS concepts. The agreement among heart failure sources ranged between 0.28 and 0.46. The contribution of these sources to the final vocabulary ranged between 18% and 49%. With the sources explored, the heart failure vocabulary reached near saturation in all four classes with the inclusion of minimal six sources (or between four to seven sources if only counting terms occurred in two or more sources). It took fewer sources to reach near saturation for the other two diseases in terms of the treatment class. Conclusions We developed a method for the development of

  5. Evaluation of Anatomical and Functional Hip Joint Center Methods: The Effects of Activity Type, Gender, and Proximal Reference Segment.

    PubMed

    McGibbon, C A; Fowler, J; Chase, S; Steeves, K; Landry, J; Mohamed, A

    2016-01-01

    Accurate hip joint center (HJC) location is critical when studying hip joint biomechanics. The HJC is often determined from anatomical methods, but functional methods are becoming increasingly popular. Several studies have examined these methods using simulations and in vivo gait data, but none has studied high-range of motion activities, such a chair rise, nor has HJC prediction been compared between males and females. Furthermore, anterior superior iliac spine (ASIS) marker visibility during chair rise can be problematic, requiring a sacral cluster as an alternative proximal segment; but functional HJC has not been explored using this approach. For this study, the quality of HJC measurement was based on the joint gap error (JGE), which is the difference in global HJC between proximal and distal reference segments. The aims of the present study were to: (1) determine if JGE varies between pelvic and sacral referenced HJC for functional and anatomical methods, (2) investigate which functional calibration motion results in the lowest JGE and if the JGE varies depending on movement type (gait versus chair rise) and gender, and (3) assess whether the functional HJC calibration results in lower JGE than commonly used anatomical approaches and if it varies with movement type and gender. Data were collected on 39 healthy adults (19 males and 20 females) aged 14-50 yr old. Participants performed four hip "calibration" tests (arc, cross, star, and star-arc), as well as gait and chair rise (activities of daily living (ADL)). Two common anatomical methods were used to estimate HJC and were compared to HJC computed using a published functional method with the calibration motions above, when using pelvis or sacral cluster as the proximal reference. For ADL trials, functional methods resulted in lower JGE (12-19 mm) compared to anatomical methods (13-34 mm). It was also found that women had significantly higher JGE compared to men and JGE was significantly higher for

  6. Development of liquid chromatographic methods for the determination of phytosterols in Standard Reference Materials containing saw palmetto.

    PubMed

    Bedner, Mary; Schantz, Michele M; Sander, Lane C; Sharpless, Katherine E

    2008-05-23

    Liquid chromatographic (LC) methods using atmospheric pressure chemical ionization/mass spectrometric (APCI-MS) detection were developed for the separation and analysis of the phytosterols campesterol, cycloartenol, lupenone, lupeol, beta-sitosterol, and stigmasterol. Brassicasterol and cholesterol were also included for investigation as internal standards. The methods were used to identify and quantify the phytosterols in each of two Serenoa repens (saw palmetto) Standard Reference Materials (SRMs) developed by the National Institute of Standards and Technology (NIST). Values obtained by LC-MS were compared to those obtained using the more traditional approach of gas chromatography with flame ionization detection. This is the first reported use of LC-MS to determine phytosterols in saw palmetto dietary supplement materials.

  7. Effect of ribonucleic acid (RNA) isolation methods on putative reference genes messenger RNA abundance in human spermatozoa.

    PubMed

    Barragán, M; Martínez, A; Llonch, S; Pujol, A; Vernaeve, V; Vassena, R

    2015-07-01

    Although the male gamete participates in a significant proportion of infertility cases, there are currently no proven molecular markers of sperm quality. The search for significant gene expression markers is partially hindered by the lack of a recognized set of reference genes (RGs) to normalize reverse transcription quantitative PCR (RT-qPCR) data across studies. The aim of this study is to define a set of RGs in assisted reproduction patients undergoing different sample collection and RNA isolation methods. Twenty-two normozoospermic men were included in the study. From each man, semen was either cryopreserved by slow freezing or analyzed fresh, and, for each, RNA was extracted with either phenol-free or phenol-based methods. In two cases, both methods were used to isolate RNA. Twenty putative RGs were analyzed and their mRNA abundance across samples was estimated by RT-qPCR. To determine the genes whose steady-state mRNA abundance remains unchanged, three different algorithms (geNorm, BestKeeper and NormFinder) were applied to the qPCR data. We found that RGs such as GAPDH or ACTB, useful in other biological contexts, cannot be used as reference for human spermatozoa. It is possible to compare gene expression from fresh and cryopreserved sperm samples using the same isolation method, while the mRNA abundance of expressed genes becomes different depending on the RNA isolation technique employed. In our conditions, the most appropriate RGs for RT-qPCR analysis were RPLP1, RPL13A, and RPLP2. Published discrepancies in gene expression studies in human spermatozoa may be due in part to inappropriate RGs selection, suggesting a possible different interpretation of PCR data in several reports, which were normalized using unstable RGs.

  8. Revised Reference Broth Microdilution Method for Testing Telavancin: Effect on MIC Results and Correlation with Other Testing Methodologies

    PubMed Central

    Mendes, Rodrigo E.; Rhomberg, Paul R.; Jones, Ronald N.

    2014-01-01

    The reference broth microdilution (BMD) antimicrobial susceptibility testing method for telavancin was revised to include dimethyl sulfoxide (DMSO) as a solvent and diluent for frozen-form panel preparation, following the CLSI recommendations for water-insoluble agents. Polysorbate 80 (P-80) was also added to the test medium to minimize proven drug losses associated with binding to plastic surfaces. Four hundred sixty-two Gram-positive isolates, including a challenge set of organisms with reduced susceptibilities to comparator agents, were selected and tested using the revised method for telavancin, and the MIC results were compared with those tested by the previously established method and several Sensititre dry-form BMD panel formulations. The revised method provided MIC results 2- to 8-fold lower than the previous method when tested against staphylococci and enterococci, resulting in MIC50 values of 0.03 to 0.06 μg/ml for staphylococci and 0.03 and 0.12 μg/ml for Enterococcus faecium and Enterococcus faecalis, respectively. Less-significant MIC decreases (1 to 2 log2 dilution steps) were observed when testing streptococci in broth supplemented with blood, which showed similar MIC50 values for both methods. However, Streptococcus pneumoniae had MIC50 results of 0.008 and 0.03 μg/ml when tested by the revised and previous methods, respectively. Highest essential agreement rates (≥94.0%) were noted for one candidate dry-form panel formulation compared to the revised test. The revised BMD method provides lower MIC results for telavancin, especially when tested against staphylococci and enterococci. This is secondary to the use of DMSO for panel production and the presence of P-80, which ensure the proper telavancin testing concentration and result in a more accurate MIC determination. Moreover, earlier studies where the previous method was applied underestimated the in vitro drug potency. PMID:25022579

  9. A method for the development of disease-specific reference standards vocabularies from textual biomedical literature resources.

    PubMed

    Wang, Liqin; Bray, Bruce E; Shi, Jianlin; Del Fiol, Guilherme; Haug, Peter J

    2016-03-01

    Disease-specific vocabularies are fundamental to many knowledge-based intelligent systems and applications like text annotation, cohort selection, disease diagnostic modeling, and therapy recommendation. Reference standards are critical in the development and validation of automated methods for disease-specific vocabularies. The goal of the present study is to design and test a generalizable method for the development of vocabulary reference standards from expert-curated, disease-specific biomedical literature resources. We formed disease-specific corpora from literature resources like textbooks, evidence-based synthesized online sources, clinical practice guidelines, and journal articles. Medical experts annotated and adjudicated disease-specific terms in four classes (i.e., causes or risk factors, signs or symptoms, diagnostic tests or results, and treatment). Annotations were mapped to UMLS concepts. We assessed source variation, the contribution of each source to build disease-specific vocabularies, the saturation of the vocabularies with respect to the number of used sources, and the generalizability of the method with different diseases. The study resulted in 2588 string-unique annotations for heart failure in four classes, and 193 and 425 respectively for pulmonary embolism and rheumatoid arthritis in treatment class. Approximately 80% of the annotations were mapped to UMLS concepts. The agreement among heart failure sources ranged between 0.28 and 0.46. The contribution of these sources to the final vocabulary ranged between 18% and 49%. With the sources explored, the heart failure vocabulary reached near saturation in all four classes with the inclusion of minimal six sources (or between four to seven sources if only counting terms occurred in two or more sources). It took fewer sources to reach near saturation for the other two diseases in terms of the treatment class. We developed a method for the development of disease-specific reference vocabularies

  10. Reference method for detection of Pgp mediated multidrug resistance in human hematological malignancies: a method validated by the laboratories of the French Drug Resistance Network.

    PubMed

    Huet, S; Marie, J P; Gualde, N; Robert, J

    1998-12-15

    Multidrug resistance (MDR) associated with overexpression of the MDR1 gene and of its product, P-glycoprotein (Pgp), plays an important role in limiting cancer treatment efficacy. Many studies have investigated Pgp expression in clinical samples of hematological malignancies but failed to give definitive conclusion on its usefulness. One convenient method for fluorescent detection of Pgp in malignant cells is flow cytometry which however gives variable results from a laboratory to another one, partly due to the lack of a reference method rigorously tested. The purpose of this technical note is to describe each step of a reference flow cytometric method. The guidelines for sample handling, staining and analysis have been established both for Pgp detection with monoclonal antibodies directed against extracellular epitopes (MRK16, UIC2 and 4E3), and for Pgp functional activity measurement with Rhodamine 123 as a fluorescent probe. Both methods have been validated on cultured cell lines and clinical samples by 12 laboratories of the French Drug Resistance Network. This cross-validated multicentric study points out crucial steps for the accuracy and reproducibility of the results, like cell viability, data analysis and expression.

  11. 41 CFR 302-7.15 - Must I use the method selected by my agency for transporting my HHG, PBP&E and temporary storage?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... selected by my agency for transporting my HHG, PBP&E and temporary storage? 302-7.15 Section 302-7.15... TRANSPORTATION AND STORAGE OF PROPERTY 7-TRANSPORTATION AND TEMPORARY STORAGE OF HOUSEHOLD GOODS AND PROFESSIONAL BOOKS, PAPERS, AND EQUIPMENT (PBP&E) General Rules § 302-7.15 Must I use the method selected by...

  12. 41 CFR 302-7.15 - Must I use the method selected by my agency for transporting my HHG, PBP&E and temporary storage?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... selected by my agency for transporting my HHG, PBP&E and temporary storage? 302-7.15 Section 302-7.15... TRANSPORTATION AND STORAGE OF PROPERTY 7-TRANSPORTATION AND TEMPORARY STORAGE OF HOUSEHOLD GOODS AND PROFESSIONAL BOOKS, PAPERS, AND EQUIPMENT (PBP&E) General Rules § 302-7.15 Must I use the method selected by...

  13. INTERLABORATORY EVALUATION OF MI AGAR AND THE US ENVIRONMENTAL PROTECTION AGENCY-APPROVED MEMBRANE FILTER METHOD FOR THE RECOVERY OF TOTAL COLIFORMS AND ESCHERICHIA COLI FROM DRINKING WATER

    EPA Science Inventory

    A new membrane filter (MF) medium, MI agar, recently validated for use in recovering chlorine-damaged total coloiforms (TC) and Escherichia coli from drinking water, was compared to the US Environmental Protection Agency (EPA)-approved MF method(mEndo agar and nutrient agar suppl...

  14. Method validation and reference range values for a peripheral blood immunophenotyping assay in non-human primates.

    PubMed

    Caldwell, Robert G; Marshall, Peggy; Fishel, Jared

    2016-01-01

    A peripheral blood immunophenotyping assay was developed and validated for determination of total T-lymphocytes, helper T-lymphocytes, cytotoxic T-lymphocytes, B-lymphocytes, and natural killer cells in cynomolgus monkeys. Validation parameters included assessment of precision, linearity, antibody optimization, stability of peripheral blood samples, and stability of fixed immunophenotyping samples. Total lymphocyte populations were determined using a heterogeneous lymphocyte gating strategy consisting of CD45 fluorescent staining and side-scatter demarcation. Relative lymphocyte subset values were determined using antigen-specific gating strategies. Absolute subset concentrations for each lymphocyte subset were subsequently determined using a dual-platform methodology wherein relative lymphocyte subset values (via flow cytometry analyses) were multiplied by the absolute total lymphocyte (via hematology analyses) values. Reference ranges are presented for cynomolgus monkey, rhesus monkey, and baboon. Additional 1-year longitudinal immunophenotyping values are presented for the cynomolgus monkey. The method validation and reference ranges presented in this research provide a robust analytical methodology for determination of peripheral blood lymphocyte subsets in various non-human primate species.

  15. Measurement of carboxyhemoglobin and total hemoglobin by five specialized spectrophotometers (CO-oximeters) in comparison with reference methods.

    PubMed

    Mahoney, J J; Vreman, H J; Stevenson, D K; Van Kessel, A L

    1993-08-01

    We measured total hemoglobin (CtHb) and carboxyhemoglobin (COHb) in 100 patients' blood samples by using five specialized spectrophotometers (CO-oximeters)--IL 482 CO-Oximeter, Corning 2500 CO-oximeter, Radiometer OSM 3 Hemoximeter, Corning 270 CO-oximeter, and the AVL 912 CO-Oxylite--and compared the results with those obtained with the manual cyanmethemoglobin method and a gas-chromatographic (GC) method, respectively. For the CtHb measurements, the differences between the cyanmethemoglobin method and the CO-oximeters were not clinically important for any model. For the blood COHb measurements, the direction of the bias relative to GC was dependent on COHb concentration. In general, the CO-oximeters underestimated COHb concentration for COHb > 2.5% of total hemoglobin but overestimated COHb concentration for COHb < or = 2.5%. We conclude that all five CO-oximeters compared favorably with the reference methods for CtHb and for high concentrations of COHb. However, the inaccuracy of CO-oximeters for low-concentration (< or = 2.5%) COHb measurements may make these instruments unsuitable for some applications.

  16. A novel method of calibrating a MEMS inertial reference unit on a turntable under limited working conditions

    NASA Astrophysics Data System (ADS)

    Lu, Jiazhen; Liang, Shufang; Yang, Yanqiang

    2017-10-01

    Micro-electro-mechanical systems (MEMS) inertial measurement devices tend to be widely used in inertial navigation systems and have quickly emerged on the market due to their characteristics of low cost, high reliability and small size. Calibration is the most effective way to remove the deterministic error of an inertial reference unit (IRU), which in this paper consists of three orthogonally mounted MEMS gyros. However, common testing methods in the lab cannot predict the corresponding errors precisely when the turntable’s working condition is restricted. In this paper, the turntable can only provide a relatively small rotation angle. Moreover, the errors must be compensated exactly because of the great effect caused by the high angular velocity of the craft. To deal with this question, a new method is proposed to evaluate the MEMS IRU’s performance. In the calibration procedure, a one-axis table that can rotate a limited angle in the form of a sine function is utilized to provide the MEMS IRU’s angular velocity. A new algorithm based on Fourier series is designed to calculate the misalignment and scale factor errors. The proposed method is tested in a set of experiments, and the calibration results are compared to a traditional calibration method performed under normal working conditions to verify their correctness. In addition, a verification test in the given rotation speed is implemented for further demonstration.

  17. Validation study to demonstrate the equivalence of a minor modification (TECRA ULTIMA protocol) to AOAC Method 998.09 (TECRA Salmonella Visual Immunoassay) with the cultural reference method.

    PubMed

    Briggs, Julie; Dailianis, Angela; Hughes, Denise; Garthwaite, Ian

    2004-01-01

    The TECRA Salmonella Visual Immunoassay (VIA) using Rappaport-Vassiliadis RV[R10] as a single selective enrichment broth has Final Action approval (AOAC Method 998.09). TECRA has recently developed a protocol (TECRA ULTIMA), which involves the addition of a new additive to a 1 mL aliquot of the RV[R10] broth, prior to the heat-killing step, thereby allowing the RV[R10] broth to be tested directly in the kit and thus eliminating the need for the 2 h post-enrichment in M broth. An in-house validation study was conducted to compare the modified AOAC Method 998.09 to the reference culture method. Three foods were used in the study: Naturally contaminated raw ground poultry at high (10-50 cells/25 g), and low (1-5 cells/25 g) levels; and milk powder and peanut butter, artificially inoculated at low and high levels with Salmonella bovismorbificans and S. enterica Mbandaka, respectively. Twenty test portions were analyzed for each level with 10 uninoculated control samples per food. Overall, no significant differences (p <0.05) were observed when the proportion of positive test portions for the modified VIA were compared with that for the reference method. This minor modification, which employs the additive (provided in the TECRA ULTIMA SALMONELLA Test Kit) to permit the direct analysis of RV[R10] broth has demonstrated the utility of the TECRA ULTIMA SALMONELLA protocol. It is recommended that the minor modification to Method 998.09 be approved First Action as an additional option within the method.

  18. Retrieving air humidity, global solar radiation, and reference evapotranspiration from daily temperatures: development and validation of new methods for Mexico. Part III: reference evapotranspiration

    NASA Astrophysics Data System (ADS)

    Lobit, P.; Gómez Tagle, A.; Bautista, F.; Lhomme, J. P.

    2017-07-01

    We evaluated two methods to estimate evapotranspiration (ETo) from minimal weather records (daily maximum and minimum temperatures) in Mexico: a modified reduced set FAO-Penman-Monteith method (Allen et al. 1998, Rome, Italy) and the Hargreaves and Samani (Appl Eng Agric 1(2): 96-99, 1985) method. In the reduced set method, the FAO-Penman-Monteith equation was applied with vapor pressure and radiation estimated from temperature data using two new models (see first and second articles in this series): mean temperature as the average of maximum and minimum temperature corrected for a constant bias and constant wind speed. The Hargreaves-Samani method combines two empirical relationships: one between diurnal temperature range ΔT and shortwave radiation Rs, and another one between average temperature and the ratio ETo/Rs: both relationships were evaluated and calibrated for Mexico. After performing a sensitivity analysis to evaluate the impact of different approximations on the estimation of Rs and ETo, several model combinations were tested to predict ETo from daily maximum and minimum temperature alone. The quality of fit of these models was evaluated on 786 weather stations covering most of the territory of Mexico. The best method was found to be a combination of the FAO-Penman-Monteith reduced set equation with the new radiation estimation and vapor pressure model. As an alternative, a recalibration of the Hargreaves-Samani equation is proposed.

  19. A cross-sectional study on sarcopenia using different methods: reference values for healthy Saudi young men.

    PubMed

    Alkahtani, Shaea A

    2017-03-21

    The aim of this study was to determine reference values for sarcopenia indices using different methods in healthy Saudi young men. Participants included 232 Saudi men aged between 20 and 35 years. The study measured anthropometric indices, blood pressure, hand grip strength, and lean muscle mass using dual-energy X-ray absorptiometry (DXA), and bioelectrical impedance analysis (BIA) was performed using Inbody 770 and Tanita 980 devices. Using DXA, the mean value of appendicular lean mass divided by the height squared (ALM/ht(2)) was found to be 8.97 ± 1.23 kg/m(2); hand grip strength measured 42.8 ± 7.6 kg. While the differences between DXA and BIA (Tanita) were significant for all parameters, the differences between DXA and Inbody values were significant only for ALM parameters. Inbody sensitivity and specificity values were 73% and 95.9%, respectively. The kappa (P = 0.80) and p values (P < 0.001) showed good agreement between Inbody and DXA, whereas Tanita sensitivity and specificity values were 54.2% and 98.3%, respectively. Bland-Altman plots for differences in lean mass values between Tanita, Inbody, and DXA methods showed very high bias for Tanita and DXA, with significant differences (P < 0.001). The cut-off values for sarcopenia indices for Saudi young men are different from those of other ethnicities. The use of tailored cut-off reference values instead of a general cut-off for BIA devices is recommended.

  20. References for marine science

    NASA Astrophysics Data System (ADS)

    1990-06-01

    Standard and Reference Materials for Marine Science, National Oceanic and Atmospheric Administration Technical Memo OMA-51 (2nd edition, 434 pp.), by A. Y. Cantillo, is now available. This compilation of reference materials was prepared at the request of the Group of Experts on Standards and Reference Materials and was printed by NOAA. GESREM is sponsored by the International Atomic Energy Agency, the Intergovernmental Oceanographic Commission, and the United Nations Program.Reference materials are included on ashes, gases, instrument performance materials, oils, physical properties, rocks, sediments, sludges, tissues and waters. For each reference material, source, description and preparation, analyses and values, cost, references, and comments are given. Indices are included for elements, isotopes and organic compounds. Cross references to Chemical Abstracts Service registry numbers and alternate names and chemical structures of organic compounds are also provided.

  1. Automating Reference Desk Files with Microcomputers in a Public Library: An Exploration of Data Resources, Methods, and Software.

    ERIC Educational Resources Information Center

    Miley, David W.

    Many reference librarians still rely on manual searches to access vertical files, ready reference files, and other information stored in card files, drawers, and notebooks scattered around the reference department. Automated access to these materials via microcomputers using database management software may speed up the process. This study focuses…

  2. Comparison of weighed food record procedures for the reference methods in two validation studies of food frequency questionnaires.

    PubMed

    Ishii, Yuri; Ishihara, Junko; Takachi, Ribeka; Shinozawa, Yurie; Imaeda, Nahomi; Goto, Chiho; Wakai, Kenji; Takahashi, Toshiaki; Iso, Hiroyasu; Nakamura, Kazutoshi; Tanaka, Junta; Shimazu, Taichi; Yamaji, Taiki; Sasazuki, Shizuka; Sawada, Norie; Iwasaki, Motoki; Mikami, Haruo; Kuriki, Kiyonori; Naito, Mariko; Okamoto, Naoko; Kondo, Fumi; Hosono, Satoyo; Miyagawa, Naoko; Ozaki, Etsuko; Katsuura-Kamano, Sakurako; Ohnaka, Keizo; Nanri, Hinako; Tsunematsu-Nakahata, Noriko; Kayama, Takamasa; Kurihara, Ayako; Kojima, Shiomi; Tanaka, Hideo; Tsugane, Shoichiro

    2017-07-01

    Although open-ended dietary assessment methods, such as weighed food records (WFRs), are generally considered to be comparable, differences between procedures may influence outcome when WFRs are conducted independently. In this paper, we assess the procedures of WFRs in two studies to describe their dietary assessment procedures and compare the subsequent outcomes. WFRs of 12 days (3 days for four seasons) were conducted as reference methods for intake data, in accordance with the study protocol, among a subsample of participants of two large cohort studies. We compared the WFR procedures descriptively. We also compared some dietary intake variables, such as the frequency of foods and dishes and contributing foods, to determine whether there were differences in the portion size distribution and intra- and inter-individual variation in nutrient intakes caused by the difference in procedures. General procedures of the dietary records were conducted in accordance with the National Health and Nutrition Survey and were the same for both studies. Differences were seen in 1) selection of multiple days (non-consecutive days versus consecutive days); and 2) survey sheet recording method (individual versus family participation). However, the foods contributing to intake of energy and selected nutrients, the portion size distribution, and intra- and inter-individual variation in nutrient intakes were similar between the two studies. Our comparison of WFR procedures in two independent studies revealed several differences. Notwithstanding these procedural differences, however, the subsequent outcomes were similar. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  3. An Innovative Method for Evaluating Strategic Goals in a Public Agency: Conservation Leadership in the U.S. Forest Service

    Treesearch

    David N. Bengston; David P. Fan

    1999-01-01

    This article presents an innovative methodology for evaluating strategic planning goals in a public agency. Computer-coded content analysis was used to evaluate attitudes expressed in about 28,000 on-line news media stories about the U.S. Department of Agriculture Forest Service and its strategic goal of conservation leadership. Three dimensions of conservation...

  4. Method applied to the background analysis of energy data to be considered for the European Reference Life Cycle Database (ELCD).

    PubMed

    Fazio, Simone; Garraín, Daniel; Mathieux, Fabrice; De la Rúa, Cristina; Recchioni, Marco; Lechón, Yolanda

    2015-01-01

    Under the framework of the European Platform on Life Cycle Assessment, the European Reference Life-Cycle Database (ELCD - developed by the Joint Research Centre of the European Commission), provides core Life Cycle Inventory (LCI) data from front-running EU-level business associations and other sources. The ELCD contains energy-related data on power and fuels. This study describes the methods to be used for the quality analysis of energy data for European markets (available in third-party LC databases and from authoritative sources) that are, or could be, used in the context of the ELCD. The methodology was developed and tested on the energy datasets most relevant for the EU context, derived from GaBi (the reference database used to derive datasets for the ELCD), Ecoinvent, E3 and Gemis. The criteria for the database selection were based on the availability of EU-related data, the inclusion of comprehensive datasets on energy products and services, and the general approval of the LCA community. The proposed approach was based on the quality indicators developed within the International Reference Life Cycle Data System (ILCD) Handbook, further refined to facilitate their use in the analysis of energy systems. The overall Data Quality Rating (DQR) of the energy datasets can be calculated by summing up the quality rating (ranging from 1 to 5, where 1 represents very good, and 5 very poor quality) of each of the quality criteria indicators, divided by the total number of indicators considered. The quality of each dataset can be estimated for each indicator, and then compared with the different databases/sources. The results can be used to highlight the weaknesses of each dataset and can be used to guide further improvements to enhance the data quality with regard to the established criteria. This paper describes the application of the methodology to two exemplary datasets, in order to show the potential of the methodological approach. The analysis helps LCA

  5. Improvement of the banana "Musa acuminata" reference sequence using NGS data and semi-automated bioinformatics methods.

    PubMed

    Martin, Guillaume; Baurens, Franc-Christophe; Droc, Gaëtan; Rouard, Mathieu; Cenci, Alberto; Kilian, Andrzej; Hastie, Alex; Doležel, Jaroslav; Aury, Jean-Marc; Alberti, Adriana; Carreel, Françoise; D'Hont, Angélique

    2016-03-16

    Recent advances in genomics indicate functional significance of a majority of genome sequences and their long range interactions. As a detailed examination of genome organization and function requires very high quality genome sequence, the objective of this study was to improve reference genome assembly of banana (Musa acuminata). We have developed a modular bioinformatics pipeline to improve genome sequence assemblies, which can handle various types of data. The pipeline comprises several semi-automated tools. However, unlike classical automated tools that are based on global parameters, the semi-automated tools proposed an expert mode for a user who can decide on suggested improvements through local compromises. The pipeline was used to improve the draft genome sequence of Musa acuminata. Genotyping by sequencing (GBS) of a segregating population and paired-end sequencing were used to detect and correct scaffold misassemblies. Long insert size paired-end reads identified scaffold junctions and fusions missed by automated assembly methods. GBS markers were used to anchor scaffolds to pseudo-molecules with a new bioinformatics approach that avoids the tedious step of marker ordering during genetic map construction. Furthermore, a genome map was constructed and used to assemble scaffolds into super scaffolds. Finally, a consensus gene annotation was projected on the new assembly from two pre-existing annotations. This approach reduced the total Musa scaffold number from 7513 to 1532 (i.e. by 80%), with an N50 that increased from 1.3 Mb (65 scaffolds) to 3.0 Mb (26 scaffolds). 89.5% of the assembly was anchored to the 11 Musa chromosomes compared to the previous 70%. Unknown sites (N) were reduced from 17.3 to 10.0%. The release of the Musa acuminata reference genome version 2 provides a platform for detailed analysis of banana genome variation, function and evolution. Bioinformatics tools developed in this work can be used to improve genome sequence assemblies in

  6. Development and Implementation of a Coagulation Factor Testing Method Utilizing Autoverification in a High-volume Clinical Reference Laboratory Environment

    PubMed Central

    Riley, Paul W.; Gallea, Benoit; Valcour, Andre

    2017-01-01

    Background: Testing coagulation factor activities requires that multiple dilutions be assayed and analyzed to produce a single result. The slope of the line created by plotting measured factor concentration against sample dilution is evaluated to discern the presence of inhibitors giving rise to nonparallelism. Moreover, samples producing results on initial dilution falling outside the analytic measurement range of the assay must be tested at additional dilutions to produce reportable results. Methods: The complexity of this process has motivated a large clinical reference laboratory to develop advanced computer algorithms with automated reflex testing rules to complete coagulation factor analysis. A method was developed for autoverification of coagulation factor activity using expert rules developed with on an off the shelf commercially available data manager system integrated into an automated coagulation platform. Results: Here, we present an approach allowing for the autoverification and reporting of factor activity results with greatly diminished technologist effort. Conclusions: To the best of our knowledge, this is the first report of its kind providing a detailed procedure for implementation of autoverification expert rules as applied to coagulation factor activity testing. Advantages of this system include ease of training for new operators, minimization of technologist time spent, reduction of staff fatigue, minimization of unnecessary reflex tests, optimization of turnaround time, and assurance of the consistency of the testing and reporting process. PMID:28706751

  7. A comparative uncertainty study of the calibration of macrolide antibiotic reference standards using quantitative nuclear magnetic resonance and mass balance methods.

    PubMed

    Liu, Shu-Yu; Hu, Chang-Qin

    2007-10-17

    This study introduces the general method of quantitative nuclear magnetic resonance (qNMR) for the calibration of reference standards of macrolide antibiotics. Several qNMR experimental conditions were optimized including delay, which is an important parameter of quantification. Three kinds of macrolide antibiotics were used to validate the accuracy of the qNMR method by comparison with the results obtained by the high performance liquid chromatography (HPLC) method. The purities of five common reference standards of macrolide antibiotics were measured by the 1H qNMR method and the mass balance method, respectively. The analysis results of the two methods were compared. The qNMR is quick and simple to use. In a new medicine research and development process, qNMR provides a new and reliable method for purity analysis of the reference standard.

  8. EPA (Environmental Protection Agency) method study 24, method 601--purgeable halocarbons by the purge trap method. Final report September 1979-December 1982

    SciTech Connect

    Warner, B.J.; Friedman, C.S.; Metcalfe, L.; Morrow, T.J.; Snyder, A.D.

    1984-07-01

    The experimental design and results of a validations study for an analytical method to detect 29 halocarbons in water are described herein. In Method 601, the halocarbons are purged by an inert gas which is bubbled through the aqueous sample. The vapors are then trapped in a short column containing a suitable sorbent. The trapped components are then thermally desorbed onto the head of a chromatographic column and measured by means of halide specific detector. In this study, the 29 halocarbon compounds were divided into three separate mixes to minimize interferences from co-eluting peaks. The spiking solutions employed in the study contained the 29 halocarbons at six concentrations. Six water matrices were used in the study: distilled water, drinking water, and a surface water all supplied by the cooperating laboratories; and three industrial wastewaters supplied by the Monsanto Company. Statistical analyses and conclusions in this report are based on analytical data obtained by 20 collaborating laboratories.

  9. Reference values assessment in a Mediterranean population for small dense low-density lipoprotein concentration isolated by an optimized precipitation method

    PubMed Central

    Fernández-Cidón, Bárbara; Padró-Miquel, Ariadna; Alía-Ramos, Pedro; Castro-Castro, María José; Fanlo-Maresma, Marta; Dot-Bach, Dolors; Valero-Politi, José; Pintó-Sala, Xavier; Candás-Estébanez, Beatriz

    2017-01-01

    Background High serum concentrations of small dense low-density lipoprotein cholesterol (sd-LDL-c) particles are associated with risk of cardiovascular disease (CVD). Their clinical application has been hindered as a consequence of the laborious current method used for their quantification. Objective Optimize a simple and fast precipitation method to isolate sd-LDL particles and establish a reference interval in a Mediterranean population. Materials and methods Forty-five serum samples were collected, and sd-LDL particles were isolated using a modified heparin-Mg2+ precipitation method. sd-LDL-c concentration was calculated by subtracting high-density lipoprotein cholesterol (HDL-c) from the total cholesterol measured in the supernatant. This method was compared with the reference method (ultracentrifugation). Reference values were estimated according to the Clinical and Laboratory Standards Institute and The International Federation of Clinical Chemistry and Laboratory Medicine recommendations. sd-LDL-c concentration was measured in serums from 79 subjects with no lipid metabolism abnormalities. Results The Passing–Bablok regression equation is y = 1.52 (0.72 to 1.73) + 0.07x (−0.1 to 0.13), demonstrating no significant statistical differences between the modified precipitation method and the ultracentrifugation reference method. Similarly, no differences were detected when considering only sd-LDL-c from dyslipidemic patients, since the modifications added to the precipitation method facilitated the proper sedimentation of triglycerides and other lipoproteins. The reference interval for sd-LDL-c concentration estimated in a Mediterranean population was 0.04–0.47 mmol/L. Conclusion An optimization of the heparin-Mg2+ precipitation method for sd-LDL particle isolation was performed, and reference intervals were established in a Spanish Mediterranean population. Measured values were equivalent to those obtained with the reference method, assuring its clinical

  10. Live, Digital Reference.

    ERIC Educational Resources Information Center

    Kenney, Brian

    2002-01-01

    Discusses digital reference services, also known as virtual reference, chat reference, or online reference, based on a round table discussion at the 2002 American Library Association annual conference in Atlanta. Topics include numbers and marketing; sustainability; competition and models; evaluation methods; outsourcing; staffing and training;…

  11. Live, Digital Reference.

    ERIC Educational Resources Information Center

    Kenney, Brian

    2002-01-01

    Discusses digital reference services, also known as virtual reference, chat reference, or online reference, based on a round table discussion at the 2002 American Library Association annual conference in Atlanta. Topics include numbers and marketing; sustainability; competition and models; evaluation methods; outsourcing; staffing and training;…

  12. Total cholesterol performance of Abell–Levy–Brodie–Kendall reference measurement procedure: Certification of Japanese in-vitro diagnostic assay manufacturers through CDC’s Cholesterol Reference Method Laboratory Network☆

    PubMed Central

    Nakamura, Masakazu; Iso, Hiroyasu; Kitamura, Akihiko; Imano, Hironori; Kiyama, Masahiko; Yokoyama, Shinji; Kayamori, Yuzo; Koyama, Isao; Nishimura, Kunihiro; Nakai, Michikazu; Dasti, Mahnaz; Vesper, Hubert W.; Teramoto, Tamio; Miyamoto, Yoshihiro

    2015-01-01

    Background Accurate measurement of total cholesterol (TC) is important for cardiovascular disease risk management. The US Centers for Disease Control and Prevention (CDC) and Cholesterol Reference Method Laboratory Network (CRMLN) perform Abell–Levy–Brodie–Kendall (AK) reference measurement procedure (RMP) for TC as a secondary reference method, and implement Certification Protocol for Manufacturers. Japanese CRMLN laboratory at Osaka performed the AK RMP for 22 years, and conducted TC certification for reagent/calibrator/instrument systems of six Japanese manufacturers every 2 years for 16 years. Osaka TC performance was examined and compared to CDC’s reference values. Methods AK RMP involved sample hydrolysis, cholesterol extraction, and determination of cholesterol levels by spectrophotometry. The Certification Protocol for Manufacturers includes comparison with AK RMP using at least 40 fresh specimens. Demonstration of average bias ≤3% and total coefficient of variation ≤3% qualified an analytical system for certification. Results In the AK RMP used in the Osaka CRMLN laboratory, the regression equation for measuring TC was y (Osaka) = 1.000x (CDC) + 0.032 (n = 619, R2 = 1.000). Six Japanese manufacturers had allowable performance for certification. Conclusions The AK RMP for TC measurement was accurate, precise, and stable for 22 years. Six Japanese manufacturers were certified for 16 years. PMID:25818239

  13. Lower Bound on Estimation Variance of the Ultrasonic Attenuation Coefficient Using the Spectral-Difference Reference-phantom Method.

    PubMed

    Samimi, Kayvan; Varghese, Tomy

    2017-05-01

    Ultrasonic attenuation is one of the primary parameters of interest in Quantitative Ultrasound (QUS). Non-invasive monitoring of tissue attenuation can provide valuable diagnostic and prognostic information to the physician. The Reference Phantom Method (RPM) was introduced as a way of mitigating some of the system-related effects and biases to facilitate clinical QUS applications. In this paper, under the assumption of diffuse scattering, a probabilistic model of the backscattered signal spectrum is used to derive a theoretical lower bound on the estimation variance of the attenuation coefficient using the Spectral-Difference RPM. The theoretical lower bound is compared to simulated and experimental attenuation estimation statistics in tissue-mimicking (TM) phantoms. Estimation standard deviation (STD) of the sample attenuation in a region of interest (ROI) of the TM phantom is measured for various combinations of processing parameters, including Radio-Frequency (RF) data block length (i.e., window length) from 3 to 17 mm, RF data block width from 10 to 100 A-lines, and number of RF data blocks per attenuation estimation ROI from 3 to 10. In addition to the Spectral-Difference RPM, local attenuation estimation for simulated and experimental data sets was also performed using a modified implementation of the Spectral Fit Method (SFM). Estimation statistics of the SFM are compared to theoretical variance predictions from the literature.(1) Measured STD curves are observed to lie above the theoretical lower bound curves, thus experimentally verifying the validity of the derived bounds. This theoretical framework benefits tissue characterization efforts by isolating processing parameter ranges that could provide required precision levels in estimation of the ultrasonic attenuation coefficient using Spectral Difference methods.

  14. Profiling the binding motif between Be and Mg in the ground state via a single-reference coupled cluster method

    NASA Astrophysics Data System (ADS)

    Sinha Mahapatra, Uttam; Banerjee, Debi; Chaudhuri, Rajat K.; Chattopadhyay, Sudip

    2015-06-01

    We present a study on the performance of our iterative triples correction for the coupled cluster singles and doubles excitations (CCSDT-1a+d) method for computation of potential energy surface (PES), spectroscopic constants, and vibrational spectrum for the ground state (X1Σ+) BeMg, where the ostensible inadequacy of the CCSD and CCSD(T) methods is quite expected. We compare our results with those obtained using state-of-the-art multireference configuration interaction (MRCI) investigations reported earlier by Kerkines and Nicolaides. Our estimated dissociation energy (417.37 cm-1), equilibrium distance (3.285 Å), and vibrational frequency (82.32 cm-1) are in good agreement with recent results of advanced MRCI calculations for X1Σ+ BeMg PES, which exhibits a shallow well of 469.4 cm-1 with a minimum at 3.241 Å and a harmonic vibrational frequency of 85.7 cm-1. Very weakly bound nature of X1Σ+ BeMg is clearly reflected from these values. In accord with MRCI studies, a comparison of BeMg with iso-valence weakly bound ground-state species, Be2 and Mg2, suggests that its characteristics do not exhibit any resemblance to Be2 rather, it shows a close kinship to Mg2. The agreement of our derived vibrational levels with those obtained via the high-level MRCI calculations is very encouraging reflecting the potential of the suitably modified single-reference coupled cluster (SRCC) method, CCSDT-1a+d as a tool for the study of multireference van der Waals systems.

  15. Total phosphorus reference condition for subalpine lakes: a comparison among traditional methods and a new process-based watershed approach.

    PubMed

    Salerno, Franco; Viviano, Gaetano; Carraro, Elisa; Manfredi, Emanuela Chiara; Lami, Andrea; Musazzi, Simona; Marchetto, Aldo; Guyennon, Nicolas; Tartari, Gianni; Copetti, Diego

    2014-12-01

    Different methods for estimating the total phosphorus (TP) reference conditions of lakes have rarely been compared. This work tests the uncertainty and accuracy of the most frequently used approaches (Morpho-edaphic index -MEI-, export coefficient, diatoms and pigment-inferred TP models) for 35 subalpine lakes. Furthermore, we propose a new process-based watershed approach that was tested on a subalpine environment and consists of combining a space for time substitution with a space for space substitution. The possible presence of uncontaminated or less contaminated environments inside or next to the watershed can be exploited by training a hydrological transport watershed model according to the uncontaminated conditions and then applying the calibration to the entire watershed, which reconstructs a natural or semi-natural TP load scenario. We found that the root mean square error (RMSE) for the MEI is 4 μg L(-1). However, its application is limited for lakes that present with an alkalinity ≤1 meq L(-1). For lakes with a higher alkalinity, we observed a loss of predictive capability that results from the lower solubility of phosphorus under conditions of high calcium content. The export coefficient model was applied with a mean export coefficient and presents similar prediction capabilities as the MEI. The chlorophyll-inferred TP model shows a higher uncertainty (RMSE = 8 μg L(-1)); however, it produced fewer underestimations and overestimations. With regards to the diatom-inferred TP model, we are only able to evaluate an uncertainty of 5 μg L(-1) at the European level. Finally, the proposed process-based watershed approach adequately predicted the reference condition of the selected lake and had an uncertainty lower than the other methods (2 μg L(-1)). We conclude by revealing the potential and limitations of this approach in the field of ecological lake modelling more and more attracted by TP pristine load inputs in studies on the effects of

  16. Isotope reference materials

    USGS Publications Warehouse

    Coplen, Tyler B.

    2010-01-01

    Measurement of the same isotopically homogeneous sample by any laboratory worldwide should yield the same isotopic composition within analytical uncertainty. International distribution of light element isotopic reference materials by the International Atomic Energy Agency and the U.S. National Institute of Standards and Technology enable laboratories to achieve this goal.

  17. Review of technical justification of assumptions and methods used by the Environmental Protection Agency for estimating risks avoided by implementing MCLs for radionuclides

    SciTech Connect

    Morris, S.C.; Rowe, M.D.; Holtzman, S.; Meinhold, A.F.

    1992-11-01

    The Environmental Protection Agency (EPA) has proposed regulations for allowable levels of radioactive material in drinking water (40 CFR Part 141, 56 FR 33050, July 18, 1991). This review examined the assumptions and methods used by EPA in calculating risks that would be avoided by implementing the proposed Maximum Contaminant Levels for uranium, radium, and radon. Proposed limits on gross alpha and beta-gamma emitters were not included in this review.

  18. An old method facing a new challenge: re-visiting housekeeping proteins as internal reference control for neuroscience research

    PubMed Central

    Li, Rena; Shen, Yong

    2013-01-01

    Study of specific target protein expression is often performed by western blotting, a commonly used method to measure the protein expression in neuroscience research by specific antibodies. Housekeeping proteins are used as an internal control for protein loading as well as reference in the western blotting analysis. This practice is based on the belief that such housekeeping genes are considered to be ubiquitously and constitutively expressed in every tissue and produce the minimal essential transcripts necessary for normal cellular function. The most commonly used housekeeping proteins are β-actin, β-tubulin, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). However, recent studies have shown significant variation in some housekeeping genes both at the mRNA and protein levels in various neuropathological events, such as spinal cord injury and Alzheimer's diseases. Changes of housekeeping genes are also induced by non-neuronal diseases in various tissues. Therefore, these discoveries raise a potential concern regarding whether using a housekeeping protein as an internal standard for target protein analysis is an appropriate practice. This mini review will focus on (I) the effects of neuronal and non-neuronal diseases, experimental condition, and tissues-specific roles on alteration of housekeeping genes, and (II) alternative internal standards for gene and protein expression analysis. PMID:23454168

  19. Standard Reference Materials (SRMs) for the Calibration and Validation of Analytical Methods for PCBs (as Aroclor Mixtures)

    PubMed Central

    Poster, Dianne L.; Schantz, Michele M.; Leigh, Stefan D.; Wise, Stephen A.

    2004-01-01

    Six Standard Reference Materials (SRMs®) have been prepared by the National Institute of Standards and Technology (NIST) for the determination of PCBs as different Aroclor mixtures in methanol. Six additional SRMs of the same Aroclors in transformer oil have also been prepared. Specifically, solutions of Aroclors 1016, 1232, 1242, 1254, and 1260 have been gravimetrically prepared (individually) in methanol and transformer oil, mixed, and transferred to amber glass ampoules in approximately 1.2 mL aliquots. Gas chromatography with electron capture detection (GC-ECD) has been used to verify the gravimetric data for each solution and transformer oil SRM. Liquid chromatography was used for the isolation of the Aroclors from the transformer oil SRMs prior to GC-ECD analysis. Separate calibration solutions and oils were prepared with Aroclor levels similar to those in each methanol solution and transformer oil SRM and were processed alongside the samples. The GC-ECD response of each Aroclor was monitored relative to internal standards that were added to the complex mixtures for quantification. The gravimetric concentrations of Aroclors 1242 and 1254 in methanol were also examined by the same method of analysis (GC-ECD) using several different sources of Aroclors and two different capillary GC columns: a 5 % phenyl methylpolysiloxane phase and a relatively non-polar phase. The preparation of the materials, the gas chromatographic results, and the certified concentration values for each Aroclor SRM are described in this paper. PMID:27366608

  20. Standard Reference Materials (SRMs) for the Calibration and Validation of Analytical Methods for PCBs (as Aroclor Mixtures).

    PubMed

    Poster, Dianne L; Schantz, Michele M; Leigh, Stefan D; Wise, Stephen A

    2004-01-01

    Six Standard Reference Materials (SRMs®) have been prepared by the National Institute of Standards and Technology (NIST) for the determination of PCBs as different Aroclor mixtures in methanol. Six additional SRMs of the same Aroclors in transformer oil have also been prepared. Specifically, solutions of Aroclors 1016, 1232, 1242, 1254, and 1260 have been gravimetrically prepared (individually) in methanol and transformer oil, mixed, and transferred to amber glass ampoules in approximately 1.2 mL aliquots. Gas chromatography with electron capture detection (GC-ECD) has been used to verify the gravimetric data for each solution and transformer oil SRM. Liquid chromatography was used for the isolation of the Aroclors from the transformer oil SRMs prior to GC-ECD analysis. Separate calibration solutions and oils were prepared with Aroclor levels similar to those in each methanol solution and transformer oil SRM and were processed alongside the samples. The GC-ECD response of each Aroclor was monitored relative to internal standards that were added to the complex mixtures for quantification. The gravimetric concentrations of Aroclors 1242 and 1254 in methanol were also examined by the same method of analysis (GC-ECD) using several different sources of Aroclors and two different capillary GC columns: a 5 % phenyl methylpolysiloxane phase and a relatively non-polar phase. The preparation of the materials, the gas chromatographic results, and the certified concentration values for each Aroclor SRM are described in this paper.

  1. An old method facing a new challenge: re-visiting housekeeping proteins as internal reference control for neuroscience research.

    PubMed

    Li, Rena; Shen, Yong

    2013-04-19

    The study of specific target protein expression is often performed by western blotting, a commonly used method to measure the protein expression in neuroscience research by specific antibodies. Housekeeping proteins are used as an internal control for protein loading as well as reference in the western blotting analysis. This practice is based on the belief that such housekeeping genes are considered to be ubiquitously and constitutively expressed in every tissue and produce the minimal essential transcripts necessary for normal cellular function. The most commonly used housekeeping proteins are β-actin, β-tubulin, and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). However, recent studies have shown significant variation in some housekeeping genes both at the mRNA and protein levels in various neuropathological events, such as spinal cord injury and Alzheimer's diseases. Changes of housekeeping genes are also induced by non-neuronal diseases in various tissues. Therefore, these discoveries raise a potential concern regarding whether using a housekeeping protein as an internal standard for target protein analysis is an appropriate practice. This minireview will focus on (I) the effects of neuronal and non-neuronal diseases, experimental condition, and tissue-specific roles on alteration of housekeeping genes, and (II) alternative internal standards for gene and protein expression analysis. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Hybrid solvation models for bulk, interface, and membrane: Reference interaction site methods coupled with density functional theory

    NASA Astrophysics Data System (ADS)

    Nishihara, S.; Otani, M.

    2017-09-01

    We present two hybrid solvation models for the calculation of the solvation structure with model 1 in a confined nanospace in bulk materials and model 2 at solid/liquid interfaces where an electrode is in contact with an electrolyte and a membrane is immersed into a solution. The hybrid theory is based on the reference interaction site method (RISM) for the solvent region. The electronic structure of a bulk material, an electrode, and a membrane is treated by density functional theory with the plane-wave basis and pseudopotentials technique. For model 1, we use the three-dimensional RISM (3D-RISM) by imposing a 3D periodic boundary condition on the system. However, for model 2, we reformulate the RISM by means of a two-dimensional boundary condition parallel to the surface and an open boundary condition normal to the surface. Four benchmark calculations are performed for the formaldehyde-water system, water packed into a zeolite framework, a NaCl solution in contact with an Al electrode, and an Al thin film immersed in a NaCl solution with different concentrations. The calculations are shown to be efficient and stable. Because of the flexibility of the RISM theory, the models are considered to be applicable to a wide range of solid/liquid interfaces.

  3. A proficiency test system to improve performance of milk analysis methods and produce reference values for component calibration samples for infrared milk analysis.

    PubMed

    Wojciechowski, Karen L; Melilli, Caterina; Barbano, David M

    2016-08-01

    Our goal was to determine the feasibility of combining proficiency testing, analytical method quality-assurance system, and production of reference samples for calibration of infrared milk analyzers to achieve a more efficient use of resources and reduce costs while maximizing analytical accuracy within and among milk payment-testing laboratories. To achieve this, we developed and demonstrated a multilaboratory combined proficiency testing and analytical method quality-assurance system as an approach to evaluate and improve the analytical performance of methods. A set of modified milks was developed and optimized to serve multiple purposes (i.e., proficiency testing, quality-assurance and method improvement, and to provide reference materials for calibration of secondary testing methods). Over a period of years, the approach has enabled the group of laboratories to document improved analytical performance (i.e., reduced within- and between-laboratory variation) of chemical reference methods used as the primary reference for calibration of high-speed electronic milk-testing equipment. An annual meeting of the laboratory technicians allows for review of results and discussion of each method and provides a forum for communication of experience and techniques that are of value to new analysts in the group. The monthly proficiency testing sample exchanges have the added benefit of producing all-laboratory mean reference values for a set of 14 milks that can be used for calibration, evaluation, and troubleshooting of calibration adjustment issues on infrared milk analyzers.

  4. 40 CFR Appendix G to Part 50 - Reference Method for the Determination of Lead in Total Suspended Particulate Matter

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY... Suspended Particulate Matter 1.0 Scope and Applicability Based on review of the air quality criteria and national ambient air quality standard (NAAQS) for lead (Pb) completed in 2008, the EPA made revisions...

  5. Comparative validation study to demonstrate the equivalence of a minor modification to AOAC Official Method 2005.05 Assurance GDS shiga Toxin Genes (O157) method to the reference culture method: 375 gram sample size.

    PubMed

    Feldsine, Philip T; Montgomery-Fullerton, Megan; Roa, Nerie; Kaur, Mandeep; Kerr, David E; Lienau, Andrew H; Jucker, Markus

    2013-01-01

    The Assurance GDS Shiga Toxin Genes (0157), AOAC Official MethodsM 2005.05, has been modified to include a larger sample size of 375 g. A methods comparison study was conducted to demonstrate the equivalence of this modification to the reference culture method. Ninety samples and controls, representing three foods, were analyzed. Results show no statistically detectable difference between the Assurance GDS Escherichia coli O157:H7 assay and the reference culture methods for the detection of E. coli O157:H7, other than the low level of inoculation for leaf lettuce for which the GDS gave noticeably higher recovery [difference in Probability of Detection between candidate methods (dPODc = +0.45)]. There were also suggestions of moderate differences (dPODc = +0.15 to +0.20) for ground beef and the high level of leaf lettuce, but the study size was too small to detect differences of this size. Results showed that the Assurance GDS Shiga Toxin Genes (0157) method is equivalent to the reference culture methods for the detection of Shiga toxigenic E. coli O157:H7.

  6. Comparative validation study to demonstrate the equivalence of a minor modification to AOAC official method 2005.04 assurance GdS E. coli 0157:H7 method to the reference culture method: 375 gram sample size.

    PubMed

    Feldsine, Philip T; Montgomery-Fullerton, Megan; Roa, Nerie; Kaur, Mandeep; Lienau, Andrew H; Jucker, Markus; Kerr, David E

    2013-01-01

    The Assurance GDS Escherichia coli (E. col) O157:H7, AOAC Official Method 2005.04, has been modified to include a larger sample size of 375 g. A methods comparison study was conducted to demonstrate the equivalence of this modification to the reference culture method. Ninety samples and controls, representing three foods, were analyzed. Results show no statistically detectable difference between the Assurance GDS E. coli O157:H7 assay and the reference culture methods for the detection of E. coli O157:H7, other than the low level of inoculation for leaf lettuce, for which the GDS gave noticeably higher recovery [difference in probability of detection between candidate methods (dPODc = +0.45)]. There were also suggestions of moderate differences (dPODc = +0.15 to +0.20) for ground beef and the high level of leaf lettuce, but the study size was too small to detect differences of this size. Results showed that the Assurance GDS E. coli O157:H7 method is equivalent to reference culture methods for the detection of E. coli O157:H7.

  7. Optimization of reference electrode position in a three-electrode cell for impedance measurements in lithium-ion rechargeable battery by finite element method

    NASA Astrophysics Data System (ADS)

    Hoshi, Yoshinao; Narita, Yuki; Honda, Keiichiro; Ohtaki, Tomomi; Shitanda, Isao; Itagaki, Masayuki

    2015-08-01

    We determine the proper placement of the reference electrode for impedance measurements in lithium-ion rechargeable batteries with a three-electrode cell. Calculations of the impedance spectra of the positive and negative electrodes and simulations of the current and potential distributions between them are performed using the finite element method. In the simulation, the positive and negative electrodes are symmetrical face to face. Distortions of the loops and artifact inductive loops are observed in the impedance spectra of the positive and negative electrodes when the reference electrode is between or at the edges of the electrodes. These distortions and the diameter of the artifact inductive loops become small when the reference electrode is positioned outside the area between the positive and negative electrodes. Simulations also demonstrate that current from the positive electrode can flow to the reference electrode and then the negative electrode, i.e., part of the reference electrode facing the positive electrode becomes cathode and part of the reference electrode facing the negative electrode becomes anode. Therefore, the dissolution of reference electrode occurs during impedance measurements in a three-electrode cell and the reference electrode should be placed outside of the area between electrodes, where there is no potential modulation and gradient.

  8. An analytic-numerical method for the construction of the reference law of operation for a class of mechanical controlled systems

    NASA Astrophysics Data System (ADS)

    Mizhidon, A. D.; Mizhidon, K. A.

    2017-04-01

    An analytic-numerical method for the construction of a reference law of operation for a class of dynamic systems describing vibrations in controlled mechanical systems is proposed. By the reference law of operation of a system, we mean a law of the system motion that satisfies all the requirements for the quality and design features of the system under permanent external disturbances. As disturbances, we consider polyharmonic functions with known amplitudes and frequencies of the harmonics but unknown initial phases. For constructing the reference law of motion, an auxiliary optimal control problem is solved in which the cost function depends on a weighting coefficient. The choice of the weighting coefficient ensures the design of the reference law. Theoretical foundations of the proposed method are given.

  9. Determination of serum uric acid using high-performance liquid chromatography (HPLC)/isotope dilution mass spectrometry (ID-MS) as a candidate reference method.

    PubMed

    Dai, Xinhua; Fang, Xiang; Zhang, Chunmei; Xu, Ruifeng; Xu, Bei

    2007-10-01

    Uric acid is an important diagnostic marker of catabolism of the purine nucleosides, and accurate measurements of serum uric acid are necessary for proper diagnosis of gout or renal disease appearance. A candidate reference method involving isotope dilution coupled with liquid chromatography/mass spectrometry (LC/MS) has been described. An isotopically labeled internal standard, [1,3-(15)N(2)] uric acid, was added to serum, followed by equilibration and protein removal clean up to prepare samples for liquid chromatography/mass spectrometry electrospray ionization (LC/MS-ESI) analyses. (M-H)(-) ions at m/z 167 and 169 for uric acid and its labeled internal standard were monitored for LC/MS. The accuracy of the measurement was evaluated by a comparison of results of this candidate reference method on lyophilized human serum reference materials for uric acid (Standard Reference Materials SRM909b) with the certified values determined by gas chromatography/mass spectrometry reference methods and by a recovery study for the added uric acid. The method performed well against the established reference method of ion-exchange followed by derivatization isotope dilution (ID) gas chromatography mass spectrometry (ID-GC/MS). The results of this method for uric acid agreed well with the certified values and were within 0.10%. The amounts of uric acid recovered and added were in good agreement for the three concentrations. This method was applied to determine uric acid in samples of frozen serum pools. Excellent precision was obtained with within-set CVs of 0.08-0.18% and between-set CVs of 0.02-0.07% for LC/MS analyses. Liquid chromatography/tandem mass spectrometry electrospray ionization (LC/MS/MS-ESI) analysis was also performed. The LC/MS and LC/MS/MS results were in very good agreement (within 0.14%). This LC/MS method, which demonstrates good accuracy and precision, and is in the speed of analysis without the need for a derivatization stage, qualifies as a candidate

  10. A Simple method for reference crop evapotranspiration under non-advective conditions suitable for remote sensing applications

    NASA Astrophysics Data System (ADS)

    de Bruin, Henk A. R.; Trigo, Isabel F.; Bosveld, Fred C.; Fokke Meirink, Jan

    2015-04-01

    A method is presented to estimate daily reference crop evapotranspiration (ETo) under non-advective conditions from Meteosat Second Generation (MSG) imagery. For this purpose observations of Cabauw in the Netherlands have been analyzed. Due to the climatic conditions and the local water management at this site water stress is very rare, which makes this dataset ideal to assess ETo without advection. The findings of older studies are combined to arrive at a simple formula for ETo, requiring daily global radiation and air temperature as input only. The formula is validated against independent eddy-covariance measurements of actual evapotranspiration. The bias is 3 W m-2 and the root mean square error (RMSE) 7.6 W m-2. The applied Slob-de Bruin estimate of net radiation is tested separately, yielding a bias of 1.4 W m-2 and a RMSE of 9.6 W m-2. In a next step the measured global radiation has been replaced with MSG estimates. For ETo this resulted in a bias of 1.6 W m-2 and a RMSE of 11.7 W m-2. Based on arguments used by Schmidt (1915) a reasonably sound physical justification for the proposed ETo formula is presented. This justifies application of the results outside Cabauw. However, this applies to conditions where advection can be ignored. It is pointed out that in semi-arid regions local advection cannot be ignored. Finally, the ambiguousness of the formal definition of ETo given in the FAO Irrigation and Drainage Paper No. 56 is discussed.

  11. COMPARISON OF THE RECOVERIES OF ESCHERICHIA COLI AND TOTAL COLIFORMS FROM DRINKING WATER BY THE MI AGAR METHOD AND THE U.S. ENVIRONMENTAL PROTECTION AGENCY-APPROVED MEMBRANE FILTER METHOD

    EPA Science Inventory

    Drinking water regulations under the Final Coliform Rule require that total coliform-positive drinking water samples be examined for the presence of Escherichia coli or fecal coliforms. The current U.S. Environmental Protection Agency-approved membrane filter (MF) method for E. c...

  12. COMPARISON OF THE RECOVERIES OF ESCHERICHIA COLI AND TOTAL COLIFORMS FROM DRINKING WATER BY THE MI AGAR METHOD AND THE U.S. ENVIRONMENTAL PROTECTION AGENCY-APPROVED MEMBRANE FILTER METHOD

    EPA Science Inventory

    Drinking water regulations under the Final Coliform Rule require that total coliform-positive drinking water samples be examined for the presence of Escherichia coli or fecal coliforms. The current U.S. Environmental Protection Agency-approved membrane filter (MF) method for E. c...

  13. 40 CFR Appendix O to Part 50 - Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere O Appendix O to Part 50 Protection of... Coarse Particulate Matter as PM10-2.5 in the Atmosphere 1.0Applicability and Definition 1.1This method...

  14. 40 CFR Appendix O to Part 50 - Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere O Appendix O to Part 50 Protection of... Coarse Particulate Matter as PM10-2.5 in the Atmosphere 1.0Applicability and Definition 1.1This method...

  15. 40 CFR Appendix O to Part 50 - Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 2 2012-07-01 2012-07-01 false Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere O Appendix O to Part 50 Protection of... Coarse Particulate Matter as PM10-2.5 in the Atmosphere 1.0Applicability and Definition 1.1This method...

  16. 40 CFR Appendix O to Part 50 - Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere O Appendix O to Part 50 Protection of... Coarse Particulate Matter as PM10-2.5 in the Atmosphere 1.0Applicability and Definition 1.1This method...

  17. 40 CFR Appendix O to Part 50 - Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 2 2014-07-01 2014-07-01 false Reference Method for the Determination of Coarse Particulate Matter as PM10-2.5 in the Atmosphere O Appendix O to Part 50 Protection of... Coarse Particulate Matter as PM10-2.5 in the Atmosphere 1.0Applicability and Definition 1.1This method...

  18. Sprint performance and mechanical outputs computed with an iPhone app: Comparison with existing reference methods.

    PubMed

    Romero-Franco, Natalia; Jiménez-Reyes, Pedro; Castaño-Zambudio, Adrián; Capelo-Ramírez, Fernando; Rodríguez-Juan, Juan José; González-Hernández, Jorge; Toscano-Bendala, Francisco Javier; Cuadrado-Peñafiel, Víctor; Balsalobre-Fernández, Carlos

    2017-05-01

    The purpose of this study was to assess validity and reliability of sprint performance outcomes measured with an iPhone application (named: MySprint) and existing field methods (i.e. timing photocells and radar gun). To do this, 12 highly trained male sprinters performed 6 maximal 40-m sprints during a single session which were simultaneously timed using 7 pairs of timing photocells, a radar gun and a newly developed iPhone app based on high-speed video recording. Several split times as well as mechanical outputs computed from the model proposed by Samozino et al. [(2015). A simple method for measuring power, force, velocity properties, and mechanical effectiveness in sprint running. Scandinavian Journal of Medicine & Science in Sports. https://doi.org/10.1111/sms.12490] were then measured by each system, and values were compared for validity and reliability purposes. First, there was an almost perfect correlation between the values of time for each split of the 40-m sprint measured with MySprint and the timing photocells (r = 0.989-0.999, standard error of estimate = 0.007-0.015 s, intraclass correlation coefficient (ICC) = 1.0). Second, almost perfect associations were observed for the maximal theoretical horizontal force (F0), the maximal theoretical velocity (V0), the maximal power (Pmax) and the mechanical effectiveness (DRF - decrease in the ratio of force over acceleration) measured with the app and the radar gun (r = 0.974-0.999, ICC = 0.987-1.00). Finally, when analysing the performance outputs of the six different sprints of each athlete, almost identical levels of reliability were observed as revealed by the coefficient of variation (MySprint: CV = 0.027-0.14%; reference systems: CV = 0.028-0.11%). Results on the present study showed that sprint performance can be evaluated in a valid and reliable way using a novel iPhone app.

  19. Reference values for mental health assessment instruments: objectives and methods of the Leiden Routine Outcome Monitoring Study.

    PubMed

    Schulte-van Maaren, Yvonne W M; Carlier, Ingrid V E; Giltay, Erik J; van Noorden, Martijn S; de Waal, Margot W M; van der Wee, Nic J A; Zitman, Frans G

    2013-04-01

    Routine outcome monitoring (ROM) was developed to establish the outcome of psychotherapeutic and pharmacological treatments through repeated assessments before, during and after treatment. Although standardization of psychiatric assessments and their reference values are essential for patient care, for various ROM instruments reference values are not available. The aim of the Leiden ROM Study is to generate reference values for 22 ROM instruments, covering generic and specific mood, anxiety and somatoform (MAS) disorders, for the general population. This article describes the extensive process of recruitment, as well as baseline characteristics of patient versus non-patient groups. Cross-sectional study in randomly selected participants aged 18-65 years from the Dutch population, included through general practitioners. Extensive demographic, psychosocial, mental health, and biological data from 1302 participants, recruited via general practitioners, were collected during a two-hour standardized assessment including observer-rated and self-report scales. These data will be compared with corresponding data from 7840 patients with psychopathology who were referred to secondary care. On-going quality control and calibration ensured maintenance of high quality during data collection. This reference group study for mental health assessments is the first study of this size carried out in the Netherlands. The results of this study are expected to be of value to secondary psychiatric care because they allow the indication of progress in health, treatment effect and possible termination of treatment. Additionally, the reference values can be used by primary care physicians as decision threshold for referral to specialized mental health care and vice versa. © 2012 Blackwell Publishing Ltd.

  20. The development of a rapid method for the isolation of four azaspiracids for use as reference materials for quantitative LC-MS-MS methods.

    PubMed

    Canás, Isa Ruppen; O'Callaghan, Keith; Moroney, Cian; Hamilton, Brett; James, Kevin J; Furey, Ambrose

    2010-10-01

    The azaspiracids are a family of lipophilic polyether marine biotoxins that have caused a number of human intoxication incidents in Europe since 1995 after consumption of contaminated shellfish (Mytilus edulis). Levels of azaspiracids in shellfish for human consumption are monitored in accordance with EU guidelines: only shellfish with less than 160 microg kg(-1) are deemed safe. The limited availability of commercially available standards for azaspiracids is a serious problem, because validated LC-MS methods are required for routine analysis of these toxins in shellfish tissues. The procedure described herein has been used for the separation and the isolation of four azaspiracid (AZA) toxins from shellfish, for use as LC-MS-MS reference materials. Five separation steps have been used to isolate azaspiracids 1, 2, 3, and 6. The purity of the toxins obtained has been confirmed by multiple mass spectrometric methods using authentic azaspiracid standards. The same techniques have been used for quantification of the toxins extracted. The isolation procedure involves several chromatographic purification techniques: solid-phase extraction (diol sorbent, 90% mass reduction, and 95 +/- 1% toxin recovery); Sephadex size-exclusion chromatography (87% mass reduction and up to 95 +/- 2% toxin recovery), Toyopearl HW size-exclusion chromatography (90% mass reduction and up to 92.5 +/- 2.5% toxin recovery), and semi-preparative LC (78 +/- 3% toxin recovery). The procedure effectively separates the toxins from the sample matrix and furnishes azaspiracid toxins (AZA1, AZA2, AZA3 and AZA6) of sufficient purity with an average yield of 65% (n = 5). Triple-quadrupole mass spectrometry was used for qualitative and quantitative monitoring of the isolation efficiency after each stage of the process. High-resolution mass spectrometric evaluation of the toxic isolated material in both positive and negative modes suggests high purity.

  1. Evaluation of the reference unit method for herbaceous biomass estimation in native grasslands of southwestern South Dakota

    Treesearch

    Eric D. Boyda

    2013-01-01

    The high costs associated with physically harvesting plant biomass may prevent sufficient data collection, which is necessary to account for the natural variability of vegetation at a landscape scale. A biomass estimation technique was previously developed using representative samples or "reference units", which eliminated the need to harvest biomass from all...

  2. Government Agencies

    DTIC Science & Technology

    1988-05-01

    large, complex , and difficult to manage. U.S. Government procurement is the largest business enterprise in the world affecting the security...listed in this study.) With the single exception of rocket and spacecraft acquisitions, ship acquisitions are the highest cost and most complex ...acquisitions U.S. Government agencies undertake. Many factors influence the level of complexity for a given ship acquisition program. Between the Navy and

  3. (PRESENTED AT TSUKUBA, JAPAN) PERSISTENT PERFLUORINATED ORGANIC COMPOUNDS METHOD DEVELOPMENT RESEARCH AT THE U.S. ENVIRONMENTAL PROTECTION AGENCY

    EPA Science Inventory

    PowerPoint presentation summarizing method development research involving the persistent perfluorinated organic compounds. Review of data indicating widespread distribution of these materials and the potential for toxicity.

  4. Method and apparatus for a single channel digital communications system. [synchronization of received PCM signal by digital correlation with reference signal

    NASA Technical Reports Server (NTRS)

    Couvillon, L. A., Jr.; Carl, C.; Goldstein, R. M.; Posner, E. C.; Green, R. R. (Inventor)

    1973-01-01

    A method and apparatus are described for synchronizing a received PCM communications signal without requiring a separate synchronizing channel. The technique provides digital correlation of the received signal with a reference signal, first with its unmodulated subcarrier and then with a bit sync code modulated subcarrier, where the code sequence length is equal in duration to each data bit.

  5. Twin-image reduction method for in-line digital holography using periphery and random reference phase-shifting techniques

    NASA Astrophysics Data System (ADS)

    Oshima, Teppei; Matsudo, Yusuke; Kakue, Takashi; Arai, Daisuke; Shimobaba, Tomoyoshi; Ito, Tomoyoshi

    2015-09-01

    Digital holography has the twin image problem that unwanted lights (conjugate and direct lights) overlap in the object light in the reconstruction process. As a method for extracting only the object light, phase-shifting digital holography is widely used; however, this method is not applicable for the observation of moving objects, because this method requires the recording of plural holograms. In this study, we propose a twin-image reduction method by combining the "periphery" method with the "random phase-shifting" method. The proposed method succeeded in improving the reconstruction quality, compared to other one-shot recording methods ("parallel phase-shifting digital holography" and "random phase-shifting").

  6. Certification of caffeine reference material purity by ultraviolet/visible spectrophotometry and high-performance liquid chromatography with diode-array detection as two independent analytical methods.

    PubMed

    Shehata, A B; Rizk, M S; Rend, E A

    2016-10-01

    Caffeine reference material certified for purity is produced worldwide, but no research work on the details of the certification process has been published in the literature. In this paper, we report the scientific details of the preparation and certification of pure caffeine reference materials. Caffeine was prepared by extraction from roasted and ground coffee by dichloromethane after heating in deionized water mixed with magnesium oxide. The extract was purified, dried, and bottled in dark glass vials. Stratified random selection was applied to select a number of vials for homogeneity and stability studies, which revealed that the prepared reference material is homogeneous and sufficiently stable. Quantification of caffeine purity % was carried out using a calibrated UV/visible spectrophotometer and a calibrated high-performance liquid chromatography with diode-array detection method. The results obtained from both methods were combined to drive the certified value and its associated uncertainty. The certified value of the reference material purity was found to be 99.86% and its associated uncertainty was ±0.65%, which makes the candidate reference material a very useful calibrant in food and drug chemical analysis. Copyright © 2016. Published by Elsevier B.V.

  7. Preparation of an in-house reference material containing fumonisins in Thai rice and matrix extension of the analytical method for Japanese rice.

    PubMed

    Awaludin, Norhafniza; Nagata, Reiko; Kawasaki, Tomomi; Kushiro, Masayo

    2009-12-01

    Mycotoxin contamination in rice is less reported, compared to that in wheat or maize, however, some Fusarium fungi occasionally infect rice in the paddy field. Fumonisins are mycotoxins mainly produced by Fusarium verticillioides, which often ruins maize. Rice adherent fungus Gibberella fujikuroi is taxonomically near to F. verticillioides, and there are sporadic reports of fumonisin contamination in rice from Asia, Europe and the United States. Therefore, there exists the potential risk of fumonisin contamination in rice as well as the need for the validated analytical method for fumonisins in rice. Although both natural and spiked reference materials are available for some Fusarium mycotoxins in matrices of wheat and maize, there are no reference materials for Fusarium mycotoxins in rice. In this study, we have developed a method for the preparation of a reference material containing fumonisins in Thai rice. A ShakeMaster grinding machine was used for the preparation of a mixed material of blank Thai rice and F. verticillioides-infected Thai rice. The homogeneity of the mixed material was confirmed by one-way analysis of variance, which led this material to serve as an in-house reference material. Using this reference material, several procedures to extract fumonisins from Thai rice were compared. Accordingly, we proved the applicability of an effective extraction procedure for the determination of fumonisins in Japanese rice.

  8. DETECTION OF CRYPTOSPORIDIUM OOCYSTS IN STREAM WATER SAMPLES USING U.S. ENVIRONMENTAL PROTECTION AGENCY METHOD 1622

    EPA Science Inventory

    To improve surveillance for cryptosporidium oocysts in water the USEPA developed Method 1622 which consists of filtration, concentration, immunomagnetic separation, fluorescent antibody and DAPI counter staining, and microscopic evaluation. Two filters were compared for analysis ...

  9. Comparison of Listeria monocytogenes recoveries from spiked mung bean sprouts by the enrichment methods of three regulatory agencies.

    PubMed

    Cauchon, Kaitlin E; Hitchins, Anthony D; Smiley, R Derike

    2017-09-01

    Three selective enrichment methods, the United States Food and Drug Administration's (FDA method), the United States Department of Agriculture Food Safety Inspection Service's (USDA method), and the EN ISO 11290-1 standard method, were assessed for their suitability for recovery of Listeria monocytogenes from spiked mung bean sprouts. Three parameters were evaluated; the enrichment L. monocytogenes population from singly-spiked sprouts, the enrichment L. monocytogenes population from doubly-spiked (L. monocytogenes and Listeria innocua) sprouts, and the population differential resulting from the enrichment of doubly-spiked sprouts. Considerable L. monocytogenes inter-strain variation was observed. The mean enrichment L. monocytogenes populations for singly-spiked sprouts were 6.1 ± 1.2, 4.9 ± 1.2, and 6.9 ± 2.3 log CFU/mL for the FDA, USDA, and EN ISO 11290-1 methods, respectively. The mean L. monocytogenes populations for doubly-spiked sprouts were 4.7 ± 1.1, 5.5 ± 1.3, and 4.6 ± 1.4 log CFU/mL for the FDA, USDA, and ISO 11290-1 enrichment methods, respectively. The corresponding mean population differentials were 2.8 ± 1.1, 3.3 ± 1.3, and 3.6 ± 1.4 Δlog CFU/mL for the same three enrichment methods, respectively. The presence of L. innocua and resident microorganisms on the sprouts negatively impacted final levels of L. monocytogenes with all three enrichment methods. Published by Elsevier Ltd.

  10. Comparison of different immunoassay methods to detect human anti-drug antibody using the WHO erythropoietin antibody reference panel for analytes.

    PubMed

    Shibata, Hiroko; Nishimura, Kazuko; Miyama, Chizuru; Tada, Minoru; Suzuki, Takuo; Saito, Yoshiro; Ishii-Watabe, Akiko

    2017-09-29

    Development of an appropriate assay to detect anti-drug antibody (ADA) is important for assessing immunogenicity to therapeutic protein products. However, characterizing ADA assay methods is difficult because human ADA as a reference standard is not available in most cases. We compared the analytical performance of three ligand-binding assay methods for ADA, namely, surface plasmon resonance (SPR), electrochemiluminescence (ECL), and biolayer interferometry (BLI) methods, by using the anti-erythropoietin (EPO) monoclonal antibody reference panel developed by the World Health Organization (WHO) in 2015. Dose-dependent binding responses were observed for all nine anti-EPO antibodies in the anti-EPO panel by the SPR and BLI methods. In contrast, the ECL method did not clearly detect binding of low-affinity anti-EPO antibodies. Regarding IgG2 and IgM antibodies derived from the same clone, IgG2 exhibited a higher binding response in the SPR assay, whereas the IgM binding response was higher than that of IgG2 in the ECL assay. In the case of the BLI method, there was no consistent pattern observed in the binding responses of IgG2 or IgM. Results of the anti-EPO antibody reference panel, which contains a variety of monoclonal antibodies, indicated that the ability to detect ADAs differed among these assay methods. Therefore, with ligand-binding assays, differences in assay platforms can affect the sensitivity and other characteristics of assays to detect ADAs. These results show that understanding the analytical performance of ADA assays is important for an appropriate assessment of immunogenicity. Our study also indicated the benefits of using the established human ADA reference panel to assess the assay methods for ADA detection. Copyright © 2017. Published by Elsevier B.V.

  11. Comparison between the triglycerides standardization of routine methods used in Japan and the chromotropic acid reference measurement procedure used by the CDC Lipid Standardization Programme.

    PubMed

    Nakamura, Masakazu; Iso, Hiroyasu; Kitamura, Akihiko; Imano, Hironori; Noda, Hiroyuki; Kiyama, Masahiko; Sato, Shinichi; Yamagishi, Kazumasa; Nishimura, Kunihiro; Nakai, Michikazu; Vesper, Hubert W; Teramoto, Tamio; Miyamoto, Yoshihiro

    2016-11-01

    Background The US Centers for Disease Control and Prevention ensured adequate performance of the routine triglycerides methods used in Japan by a chromotropic acid reference measurement procedure used by the Centers for Disease Control and Prevention lipid standardization programme as a reference point. We examined standardized data to clarify the performance of routine triglycerides methods. Methods The two routine triglycerides methods were the fluorometric method of Kessler and Lederer and the enzymatic method. The methods were standardized using 495 Centers for Disease Control and Prevention reference pools with 98 different concentrations ranging between 0.37 and 5.15 mmol/L in 141 survey runs. The triglycerides criteria for laboratories which perform triglycerides analyses are used: accuracy, as bias ≤5% from the Centers for Disease Control and Prevention reference value and precision, as measured by CV, ≤5%. Results The correlation of the bias of both methods to the Centers for Disease Control and Prevention reference method was: y (%bias) = 0.516 × (Centers for Disease Control and Prevention reference value) -1.292 ( n = 495, R(2 )= 0.018). Triglycerides bias at medical decision points of 1.13, 1.69 and 2.26 mmol/L was -0.71%, -0.42% and -0.13%, respectively. For the combined precision, the equation y (CV) = -0.398 × (triglycerides value) + 1.797 ( n = 495, R(2 )= 0.081) was used. Precision was 1.35%, 1.12% and 0.90%, respectively. It was shown that triglycerides measurements at Osaka were stable for 36 years. Conclusions The epidemiologic laboratory in Japan met acceptable accuracy goals for 88.7% of all samples, and met acceptable precision goals for 97.8% of all samples measured through the Centers for Disease Control and Prevention lipid standardization programme and demonstrated stable results for an extended period of time.

  12. Reducing Failures in Reference Service.

    ERIC Educational Resources Information Center

    Douglas, Ian

    1988-01-01

    Summarizes the results of 11 selected studies of the accuracy of reference services and identifies six modes of failure of reference services. Methods of detecting and reducing failure in each of these modes are then discussed. (17 references) (MES)

  13. Method development in quantitative NMR towards metrologically traceable organic certified reference materials used as (31)P qNMR standards.

    PubMed

    Weber, Michael; Hellriegel, Christine; Rueck, Alexander; Wuethrich, Juerg; Jenks, Peter; Obkircher, Markus

    2015-04-01

    Quantitative nuclear magnetic resonance (qNMR) spectroscopy is employed by an increasing number of analytical and industrial laboratories for the assignment of content and quantitative determination of impurities. Within the last few years, it was demonstrated that (1)H qNMR can be performed with high accuracy leading to measurement uncertainties below 1 % relative. It was even demonstrated that the combination of (1)H qNMR with metrological weighing can lead to measurement uncertainties below 0.1 % when highly pure substances are used. Although qNMR reference standards are already available as certified reference materials (CRM) providing traceability on the basis of (1)H qNMR experiments, there is an increasing demand for purity assays on phosphorylated organic compounds and metabolites requiring CRM for quantification by (31)P qNMR. Unfortunately, the number of available primary phosphorus standards is limited to a few inorganic CRM which only can be used for the analysis of water-soluble analytes but fail when organic solvents must be employed. This paper presents the concept of value assignment by (31)P qNMR measurements for the development of CRM and describes different approaches to establish traceability to primary Standard Reference Material from the National Institute of Standards and Technology (NIST SRM). Phosphonoacetic acid is analyzed as a water-soluble CRM candidate, whereas triphenyl phosphate is a good candidate for the use as qNMR reference material in organic solvents. These substances contain both nuclei, (1)H and (31)P, and the concept is to show that it is possible to indirectly quantify a potential phosphorus standard via its protons using (1)H qNMR. The same standard with its assigned purity can then be used for the quantification of an analyte via its phosphorus using (31)P qNMR. For the validation of the concept, triphenyl phosphate and phosphonoacetic acid have been used as (31)P qNMR standards to determine the purity of the analyte

  14. Verbal Auditory Cueing of Improvisational Dance: A Proposed Method for Training Agency in Parkinson’s Disease

    PubMed Central

    Batson, Glenna; Hugenschmidt, Christina E.; Soriano, Christina T.

    2016-01-01

    Dance is a non-pharmacological intervention that helps maintain functional independence and quality of life in people with Parkinson’s disease (PPD). Results from controlled studies on group-delivered dance for people with mild-to-moderate stage Parkinson’s have shown statistically and clinically significant improvements in gait, balance, and psychosocial factors. Tested interventions include non-partnered dance forms (ballet and modern dance) and partnered (tango). In all of these dance forms, specific movement patterns initially are learned through repetition and performed in time-to-music. Once the basic steps are mastered, students may be encouraged to improvise on the learned steps as they perform them in rhythm with the music. Here, we summarize a method of teaching improvisational dance that advances previous reported benefits of dance for people with Parkinson’s disease (PD). The method relies primarily on improvisational verbal auditory cueing with less emphasis on directed movement instruction. This method builds on the idea that daily living requires flexible, adaptive responses to real-life challenges. In PD, movement disorders not only limit mobility but also impair spontaneity of thought and action. Dance improvisation demands open and immediate interpretation of verbally delivered movement cues, potentially fostering the formation of spontaneous movement strategies. Here, we present an introduction to a proposed method, detailing its methodological specifics, and pointing to future directions. The viewpoint advances an embodied cognitive approach that has eco-validity in helping PPD meet the changing demands of daily living. PMID:26925029

  15. Reference Services.

    ERIC Educational Resources Information Center

    Bunge, Charles A.

    1999-01-01

    Discusses library reference services. Topics include the historical development of reference services; instruction in library use, particularly in college and university libraries; guidance; information and referral services and how they differ from traditional question-answering service; and future concerns, including user fees and the planning…

  16. Reference Assessment

    ERIC Educational Resources Information Center

    Bivens-Tatum, Wayne

    2006-01-01

    This article presents interesting articles that explore several different areas of reference assessment, including practical case studies and theoretical articles that address a range of issues such as librarian behavior, patron satisfaction, virtual reference, or evaluation design. They include: (1) "Evaluating the Quality of a Chat Service"…

  17. Reference Assessment

    ERIC Educational Resources Information Center

    Bivens-Tatum, Wayne

    2006-01-01

    This article presents interesting articles that explore several different areas of reference assessment, including practical case studies and theoretical articles that address a range of issues such as librarian behavior, patron satisfaction, virtual reference, or evaluation design. They include: (1) "Evaluating the Quality of a Chat Service"…

  18. Reference Services.

    ERIC Educational Resources Information Center

    Bunge, Charles A.

    1999-01-01

    Discusses library reference services. Topics include the historical development of reference services; instruction in library use, particularly in college and university libraries; guidance; information and referral services and how they differ from traditional question-answering service; and future concerns, including user fees and the planning…

  19. Reference Revolutions.

    ERIC Educational Resources Information Center

    Mason, Marilyn Gell

    1998-01-01

    Describes developments in Online Computer Library Center (OCLC) electronic reference services. Presents a background on networked cataloging and the initial implementation of reference services by OCLC. Discusses the introduction of OCLC FirstSearch service, which today offers access to over 65 databases, future developments in integrated…

  20. Child Mortality Estimation 2013: An Overview of Updates in Estimation Methods by the United Nations Inter-Agency Group for Child Mortality Estimation

    PubMed Central

    Alkema, Leontine; New, Jin Rou; Pedersen, Jon; You, Danzhen

    2014-01-01

    Background In September 2013, the United Nations Inter-agency Group for Child Mortality Estimation (UN IGME) published an update of the estimates of the under-five mortality rate (U5MR) and under-five deaths for all countries. Compared to the UN IGME estimates published in 2012, updated data inputs and a new method for estimating the U5MR were used. Methods We summarize the new U5MR estimation method, which is a Bayesian B-spline Bias-reduction model, and highlight differences with the previously used method. Differences in UN IGME U5MR estimates as published in 2012 and those published in 2013 are presented and decomposed into differences due to the updated database and differences due to the new estimation method to explain and motivate changes in estimates. Findings Compared to the previously used method, the new UN IGME estimation method is based on a different trend fitting method that can track (recent) changes in U5MR more closely. The new method provides U5MR estimates that account for data quality issues. Resulting differences in U5MR point estimates between the UN IGME 2012 and 2013 publications are small for the majority of countries but greater than 10 deaths per 1,000 live births for 33 countries in 2011 and 19 countries in 1990. These differences can be explained by the updated database used, the curve fitting method as well as accounting for data quality issues. Changes in the number of deaths were less than 10% on the global level and for the majority of MDG regions. Conclusions The 2013 UN IGME estimates provide the most recent assessment of levels and trends in U5MR based on all available data and an improved estimation method that allows for closer-to-real-time monitoring of changes in the U5MR and takes account of data quality issues. PMID:25013954

  1. Evaluation of Method-Specific Extraction Variability for the Measurement of Fatty Acids in a Candidate Infant/Adult Nutritional Formula Reference Material.

    PubMed

    Place, Benjamin J

    2017-05-01

    To address community needs, the National Institute of Standards and Technology has developed a candidate Standard Reference Material (SRM) for infant/adult nutritional formula based on milk and whey protein concentrates with isolated soy protein called SRM 1869 Infant/Adult Nutritional Formula. One major component of this candidate SRM is the fatty acid content. In this study, multiple extraction techniques were evaluated to quantify the fatty acids in this new material. Extraction methods that were based on lipid extraction followed by transesterification resulted in lower mass fraction values for all fatty acids than the values measured by methods utilizing in situ transesterification followed by fatty acid methyl ester extraction (ISTE). An ISTE method, based on the identified optimal parameters, was used to determine the fatty acid content of the new infant/adult nutritional formula reference material.

  2. International collaborative study to establish reference preparations to standardise haemagglutination testing for anti-A and anti-B in normal intravenous immunoglobulins by the direct method.

    PubMed

    Thorpe, S J; Fox, B; Sharp, G; Heath, A B; Behr-Gross, M-E; Terao, E; Virata-Theimer, M L; Yu, M W

    2010-04-01

    A joint project (coded BSP089) was run by the European Directorate for the Quality of Medicines & HealthCare (EDQM) of the Council of Europe, the National Institute for Biological Standards and Control (NIBSC) on behalf of the World Health Organization (WHO) and the Center for Biologics Evaluation and Research (CBER) of the U.S. Food and Drug Administration (FDA) to evaluate, in an international collaborative study, 3 lyophilised intravenous immunoglobulin (IVIG) preparations for their suitability to serve as Reference Preparations to standardise and control the highly variable haemagglutination testing for anti-A and anti-B in IVIG products. 23 laboratories tested candidate IVIG reference preparations consisting of a Positive control, a Negative control and a specifically formulated Limit test reference preparation to define the maximum (e.g., pharmacopoeial) limits of anti-A and anti-B haemagglutinins in IVIG products, where limits are applicable. Laboratories performed direct haemagglutination using papain-treated erythrocytes and/or indirect anti-globulin tests. For both methods, there was up to 16-fold variation in anti-A and anti-B titres, although there was good agreement over a 2-fold titre range for anti-A and anti-B between laboratories using the direct method for both the Positive control and Limit reference preparations. Comparative titration data for the Positive control and Limit reference preparations indicated that the use of a 'Limit' test reference preparation would facilitate identification of higher titre batches when the direct haemagglutination method is used. The Positive control, Negative control and Limit test preparations were adopted in November 2008 by the Commission of the European Pharmacopoeia (Ph. Eur.) as Biological Reference Preparations. The same preparations have been established as reference reagents by the WHO and the U.S FDA, including the maximal specifications defined by the Limit test preparation. This will facilitate

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

    PubMed Central

    Andreis, Elisabeth; Küllmer, Kai

    2014-01-01

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

  4. Application of the reference method isotope dilution gas chromatography mass spectrometry (ID/GC/MS) to establish metrological traceability for calibration and control of blood glucose test systems.

    PubMed

    Andreis, Elisabeth; Küllmer, Kai; Appel, Matthias

    2014-05-01

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

  5. Reference materials and representative test materials to develop nanoparticle characterization methods: the NanoChOp project case.

    PubMed

    Roebben, Gert; Kestens, Vikram; Varga, Zoltan; Charoud-Got, Jean; Ramaye, Yannic; Gollwitzer, Christian; Bartczak, Dorota; Geißler, Daniel; Noble, James; Mazoua, Stephane; Meeus, Nele; Corbisier, Philippe; Palmai, Marcell; Mihály, Judith; Krumrey, Michael; Davies, Julie; Resch-Genger, Ute; Kumarswami, Neelam; Minelli, Caterina; Sikora, Aneta; Goenaga-Infante, Heidi

    2015-01-01

    This paper describes the production and characteristics of the nanoparticle test materials prepared for common use in the collaborative research project NanoChOp (Chemical and optical characterization of nanomaterials in biological systems), in casu suspensions of silica nanoparticles and CdSe/CdS/ZnS quantum dots (QDs). This paper is the first to illustrate how to assess whether nanoparticle test materials meet the requirements of a "reference material" (ISO Guide 30, 2015) or rather those of the recently defined category of "representative test material (RTM)" (ISO/TS 16195, 2013). The NanoChOp test materials were investigated with small-angle X-ray scattering (SAXS), dynamic light scattering (DLS), and centrifugal liquid sedimentation (CLS) to establish whether they complied with the required monomodal particle size distribution. The presence of impurities, aggregates, agglomerates, and viable microorganisms in the suspensions was investigated with DLS, CLS, optical and electron microscopy and via plating on nutrient agar. Suitability of surface functionalization was investigated with attenuated total reflection Fourier transform infrared spectrometry (ATR-FTIR) and via the capacity of the nanoparticles to be fluorescently labeled or to bind antibodies. Between-unit homogeneity and stability were investigated in terms of particle size and zeta potential. This paper shows that only based on the outcome of a detailed characterization process one can raise the status of a test material to RTM or reference material, and how this status depends on its intended use.

  6. Reference materials and representative test materials to develop nanoparticle characterization methods: the NanoChOp project case

    NASA Astrophysics Data System (ADS)

    Roebben, Gert; Kestens, Vikram; Varga, Zoltan; Charoud-Got, Jean; Ramaye, Yannic; Gollwitzer, Christian; Bartczak, Dorota; Geißler, Daniel; Noble, James; Mazoua, Stéphane; Meeus, Nele; Corbisier, Philippe; Palmai, Marcell; Mihály, Judith; Krumrey, Michael; Davies, Julie; Resch-Genger, Ute; Kumarswami, Neelam; Minelli, Caterina; Sikora, Aneta; Goenaga-Infante, Heidi

    2015-10-01

    This paper describes the production and characteristics of the nanoparticle test materials prepared for common use in the collaborative research project NanoChOp (Chemical and optical characterisation of nanomaterials in biological systems), in casu suspensions of silica nanoparticles and CdSe/CdS/ZnS quantum dots. This paper is the first to illustrate how to assess whether nanoparticle test materials meet the requirements of a 'reference material' (ISO Guide 30:2015) or rather those of the recently defined category of 'representative test material' (ISO TS 16195:2013). The NanoChOp test materials were investigated with small-angle X-ray scattering (SAXS), dynamic light scattering (DLS) and centrifugal liquid sedimentation (CLS) to establish whether they complied with the required monomodal particle size distribution. The presence of impurities, aggregates, agglomerates and viable microorganisms in the suspensions was investigated with DLS, CLS, optical and electron microscopy and via plating on nutrient agar. Suitability of surface functionalization was investigated with attenuated total reflection Fourier transform infrared spectrometry (ATR-FTIR) and via the capacity of the nanoparticles to be fluorescently labeled or to bind antibodies. Between-unit homogeneity and stability were investigated in terms of particle size and zeta potential. This paper shows that only based on the outcome of a detailed characterization process one can raise the status of a test material to representative test material or reference material, and how this status depends on its intended use.

  7. Reference materials and representative test materials to develop nanoparticle characterization methods: the NanoChOp project case

    PubMed Central

    Roebben, Gert; Kestens, Vikram; Varga, Zoltan; Charoud-Got, Jean; Ramaye, Yannic; Gollwitzer, Christian; Bartczak, Dorota; Geißler, Daniel; Noble, James; Mazoua, Stephane; Meeus, Nele; Corbisier, Philippe; Palmai, Marcell; Mihály, Judith; Krumrey, Michael; Davies, Julie; Resch-Genger, Ute; Kumarswami, Neelam; Minelli, Caterina; Sikora, Aneta; Goenaga-Infante, Heidi

    2015-01-01

    This paper describes the production and characteristics of the nanoparticle test materials prepared for common use in the collaborative research project NanoChOp (Chemical and optical characterization of nanomaterials in biological systems), in casu suspensions of silica nanoparticles and CdSe/CdS/ZnS quantum dots (QDs). This paper is the first to illustrate how to assess whether nanoparticle test materials meet the requirements of a “reference material” (ISO Guide 30, 2015) or rather those of the recently defined category of “representative test material (RTM)” (ISO/TS 16195, 2013). The NanoChOp test materials were investigated with small-angle X-ray scattering (SAXS), dynamic light scattering (DLS), and centrifugal liquid sedimentation (CLS) to establish whether they complied with the required monomodal particle size distribution. The presence of impurities, aggregates, agglomerates, and viable microorganisms in the suspensions was investigated with DLS, CLS, optical and electron microscopy and via plating on nutrient agar. Suitability of surface functionalization was investigated with attenuated total reflection Fourier transform infrared spectrometry (ATR-FTIR) and via the capacity of the nanoparticles to be fluorescently labeled or to bind antibodies. Between-unit homogeneity and stability were investigated in terms of particle size and zeta potential. This paper shows that only based on the outcome of a detailed characterization process one can raise the status of a test material to RTM or reference material, and how this status depends on its intended use. PMID:26539428

  8. Factors influencing superimposition error of 3D cephalometric landmarks by plane orientation method using 4 reference points: 4 point superimposition error regression model.

    PubMed

    Hwang, Jae Joon; Kim, Kee-Deog; Park, Hyok; Park, Chang Seo; Jeong, Ho-Gul

    2014-01-01

    Superimposition has been used as a method to evaluate the changes of orthodontic or orthopedic treatment in the dental field. With the introduction of cone beam CT (CBCT), evaluating 3 dimensional changes after treatment became possible by superimposition. 4 point plane orientation is one of the simplest ways to achieve superimposition of 3 dimensional images. To find factors influencing superimposition error of cephalometric landmarks by 4 point plane orientation method and to evaluate the reproducibility of cephalometric landmarks for analyzing superimposition error, 20 patients were analyzed who had normal skeletal and occlusal relationship and took CBCT for diagnosis of temporomandibular disorder. The nasion, sella turcica, basion and midpoint between the left and the right most posterior point of the lesser wing of sphenoidal bone were used to define a three-dimensional (3D) anatomical reference co-ordinate system. Another 15 reference cephalometric points were also determined three times in the same image. Reorientation error of each landmark could be explained substantially (23%) by linear regression model, which consists of 3 factors describing position of each landmark towards reference axes and locating error. 4 point plane orientation system may produce an amount of reorientation error that may vary according to the perpendicular distance between the landmark and the x-axis; the reorientation error also increases as the locating error and shift of reference axes viewed from each landmark increases. Therefore, in order to reduce the reorientation error, accuracy of all landmarks including the reference points is important. Construction of the regression model using reference points of greater precision is required for the clinical application of this model.

  9. Factors Influencing Superimposition Error of 3D Cephalometric Landmarks by Plane Orientation Method Using 4 Reference Points: 4 Point Superimposition Error Regression Model

    PubMed Central

    Hwang, Jae Joon; Kim, Kee-Deog; Park, Hyok; Park, Chang Seo; Jeong, Ho-Gul

    2014-01-01

    Superimposition has been used as a method to evaluate the changes of orthodontic or orthopedic treatment in the dental field. With the introduction of cone beam CT (CBCT), evaluating 3 dimensional changes after treatment became possible by superimposition. 4 point plane orientation is one of the simplest ways to achieve superimposition of 3 dimensional images. To find factors influencing superimposition error of cephalometric landmarks by 4 point plane orientation method and to evaluate the reproducibility of cephalometric landmarks for analyzing superimposition error, 20 patients were analyzed who had normal skeletal and occlusal relationship and took CBCT for diagnosis of temporomandibular disorder. The nasion, sella turcica, basion and midpoint between the left and the right most posterior point of the lesser wing of sphenoidal bone were used to define a three-dimensional (3D) anatomical reference co-ordinate system. Another 15 reference cephalometric points were also determined three times in the same image. Reorientation error of each landmark could be explained substantially (23%) by linear regression model, which consists of 3 factors describing position of each landmark towards reference axes and locating error. 4 point plane orientation system may produce an amount of reorientation error that may vary according to the perpendicular distance between the landmark and the x-axis; the reorientation error also increases as the locating error and shift of reference axes viewed from each landmark increases. Therefore, in order to reduce the reorientation error, accuracy of all landmarks including the reference points is important. Construction of the regression model using reference points of greater precision is required for the clinical application of this model. PMID:25372707

  10. Child mortality estimation 2013: an overview of updates in estimation methods by the United Nations Inter-agency Group for Child Mortality Estimation.

    PubMed

    Alkema, Leontine; New, Jin Rou; Pedersen, Jon; You, Danzhen

    2014-01-01

    In September 2013, the United Nations Inter-agency Group for Child Mortality Estimation (UN IGME) published an update of the estimates of the under-five mortality rate (U5MR) and under-five deaths for all countries. Compared to the UN IGME estimates published in 2012, updated data inputs and a new method for estimating the U5MR were used. We summarize the new U5MR estimation method, which is a Bayesian B-spline Bias-reduction model, and highlight differences with the previously used method. Differences in UN IGME U5MR estimates as published in 2012 and those published in 2013 are presented and decomposed into differences due to the updated database and differences due to the new estimation method to explain and motivate changes in estimates. Compared to the previously used method, the new UN IGME estimation method is based on a different trend fitting method that can track (recent) changes in U5MR more closely. The new method provides U5MR estimates that account for data quality issues. Resulting differences in U5MR point estimates between the UN IGME 2012 and 2013 publications are small for the majority of countries but greater than 10 deaths per 1,000 live births for 33 countries in 2011 and 19 countries in 1990. These differences can be explained by the updated database used, the curve fitting method as well as accounting for data quality issues. Changes in the number of deaths were less than 10% on the global level and for the majority of MDG regions. The 2013 UN IGME estimates provide the most recent assessment of levels and trends in U5MR based on all available data and an improved estimation method that allows for closer-to-real-time monitoring of changes in the U5MR and takes account of data quality issues.

  11. A new method of passive counting of nuclear missile warheads -a white paper for the Defense Threat Reduction Agency

    SciTech Connect

    Morris, Christopher; Durham, J. Matthew; Guardincerri, Elena; Bacon, Jeffrey Darnell; Wang, Zhehui; Fellows, Shelby; Poulson, Daniel Cris; Plaud-Ramos, Kenie Omar; Daughton, Tess Marie; Johnson, Olivia Ruth

    2015-07-31

    Cosmic ray muon imaging has been studied for the past several years as a possible technique for nuclear warhead inspection and verification as part of the New Strategic Arms Reduction Treaty between the United States and the Russian Federation. The Los Alamos team has studied two different muon imaging methods for this application, using detectors on two sides and one side of the object of interest. In this report we present results obtained on single sided imaging of configurations aimed at demonstrating the potential of this technique for counting nuclear warheads in place with detectors above the closed hatch of a ballistic missile submarine.

  12. Collaborative study report: evaluation of the ATCC experimental mycoplasma reference strains panel prepared for comparison of NAT-based and conventional mycoplasma detection methods.

    PubMed

    Dabrazhynetskaya, Alena; Volokhov, Dmitriy V; Lin, Tsai-Lien; Beck, Brian; Gupta, Rajesh K; Chizhikov, Vladimir

    2013-11-01

    The main goal of this collaborative study was to evaluate the experimental panel of cryopreserved mycoplasma reference strains recently prepared by the American Type Culture Collection (ATCC(®)) in order to assess the viability and dispersion of cells in the mycoplasma stocks by measuring the ratio between the number of genomic copies (GC) and the number of colony forming units (CFU) in the reference preparations. The employment of microbial reference cultures with low GC/CFU ratios is critical for unbiased and reliable comparison of mycoplasma testing methods based on different methodological approaches, i.e., Nucleic Acid Testing (NAT) and compendial culture-based techniques. The experimental panel included ten different mycoplasma species known to represent potential human and animal pathogens as well as common contaminants of mammalian and avian cell substrates used in research, development, and manufacture of biological products. Fifteen laboratories with expertise in field of mycoplasma titration and quantification of mycoplasmal genomic DNA participated in the study conducted from February to October of 2012. The results of this study demonstrated the feasibility of preparing highly viable and dispersed (possessing low GC/CFU ratios) frozen stocks of mycoplasma reference materials, required for reliable comparison of NAT-based and conventional mycoplasma detection methods.

  13. Validation of a digital PCR method for quantification of DNA copy number concentrations by using a certified reference material.

    PubMed

    Deprez, Liesbet; Corbisier, Philippe; Kortekaas, Anne-Marie; Mazoua, Stéphane; Beaz Hidalgo, Roxana; Trapmann, Stefanie; Emons, Hendrik

    2016-09-01

    Digital PCR has become the emerging technique for the sequence-specific detection and quantification of nucleic acids for various applications. During the past years, numerous reports on the development of new digital PCR methods have been published. Maturation of these developments into reliable analytical methods suitable for diagnostic or other routine testing purposes requires their validation for the intended use. Here, the results of an in-house validation of a droplet digital PCR method are presented. This method is intended for the quantification of the absolute copy number concentration of a purified linearized plasmid in solution with a nucleic acid background. It has been investigated which factors within the measurement process have a significant effect on the measurement results, and the contribution to the overall measurement uncertainty has been estimated. A comprehensive overview is provided on all the aspects that should be investigated when performing an in-house method validation of a digital PCR method.

  14. Feeding Methods at Discharge Predict Long-Term Feeding and Neurodevelopmental Outcomes in Preterm Infants Referred for Gastrostomy Evaluation.

    PubMed

    Jadcherla, Sudarshan R; Khot, Tanvi; Moore, Rebecca; Malkar, Manish; Gulati, Ish K; Slaughter, Jonathan L

    2017-02-01

    To test the hypothesis that oral feeding at first neonatal intensive care unit discharge is associated with less neurodevelopmental impairment and better feeding milestones compared with discharge with a gastrostomy tube (G-tube). We studied outcomes for a retrospective cohort of 194 neonates <37 weeks' gestation referred for evaluation and management of feeding difficulties between July 2006 and July 2012. Discharge milestones, length of hospitalization, and Bayley Scales of Infant Development-Third Edition scores at 18-24 months were examined. χ(2), Mann-Whitney U, or t tests and multivariable logistic regression models were used. A total of 60% (n = 117) of infants were discharged on oral feedings; of these, 96% remained oral-fed at 1 year. The remaining 40% (n = 77) were discharged on G-tube feedings; of these, 31 (40%) remained G-tube dependent, 17 (22%) became oral-fed, and 29 (38%) were on oral and G-tube feedings at 1 year. Infants discharged on a G-tube had lower cognitive (P <.01), communication (P = .03), and motor (P <.01) composite scores. The presence of a G-tube, younger gestation, bronchopulmonary dysplasia, or intraventricular hemorrhage was associated significantly with neurodevelopmental delay. For infants referred for feeding concerns, G-tube evaluations, and feeding management, the majority did not require a G-tube. Full oral feeding at first neonatal intensive care unit discharge was associated with superior feeding milestones and less long-term neurodevelopmental impairment, relative to full or partial G-tube feeding. Evaluation and feeding management before and after G-tube placement may improve long-term feeding and neurodevelopmental outcomes. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Japanese Society for Laboratory Hematology flow cytometric reference method of determining the differential leukocyte count: external quality assurance using fresh blood samples.

    PubMed

    Kawai, Y; Nagai, Y; Ogawa, E; Kondo, H

    2017-04-01

    To provide target values for the manufacturers' survey of the Japanese Society for Laboratory Hematology (JSLH), accurate standard data from healthy volunteers were needed for the five-part differential leukocyte count. To obtain such data, JSLH required an antibody panel that achieved high specificity (particularly for mononuclear cells) using simple gating procedures. We developed a flow cytometric method for determining the differential leukocyte count (JSLH-Diff) and validated it by comparison with the flow cytometric differential leukocyte count of the International Council for Standardization in Haematology (ICSH-Diff) and the manual differential count obtained by microscopy (Manual-Diff). First, the reference laboratory performed an imprecision study of JSLH-Diff and ICSH-Diff, as well as performing comparison among JSLH-Diff, Manual-Diff, and ICSH-Diff. Then two reference laboratories and seven participating laboratories performed imprecision and accuracy studies of JSLH-Diff, Manual-Diff, and ICSH-Diff. Simultaneously, six manufacturers' laboratories provided their own representative values by using automated hematology analyzers. The precision of both JSLH-Diff and ICSH-Diff methods was adequate. Comparison by the reference laboratory showed that all correlation coefficients, slopes and intercepts obtained by the JSLH-Diff, ICSH-Diff, and Manual-Diff methods conformed to the criteria. When the imprecision and accuracy of JSLH-Diff were assessed at seven laboratories, the CV% for lymphocytes, neutrophils, monocytes, eosinophils, and basophils was 0.5~0.9%, 0.3~0.7%, 1.7~2.6%, 3.0~7.9%, and 3.8~10.4%, respectively. More than 99% of CD45 positive leukocytes were identified as normal leukocytes by JSLH-Diff. When JSLH-Diff method were validated by comparison with Manual-Diff and ICSH-Diff, JSLH-Diff showed good performance as a reference method. © 2016 John Wiley & Sons Ltd.

  16. Production of Landsat ETM+ reference imagery of burned areas within Southern African savannahs: comparison of methods and application to MODIS

    Treesearch

    A. M. S. Smith; N. A. Drake; M. J. Wooster; A. T. Hudak; Z. A. Holden; C. J. Gibbons

    2007-01-01

    Accurate production of regional burned area maps are necessary to reduce uncertainty in emission estimates from African savannah fires. Numerous methods have been developed that map burned and unburned surfaces. These methods are typically applied to coarse spatial resolution (1 km) data to produce regional estimates of the area burned, while higher spatial resolution...

  17. Evaluation of reference-based two-color methods for measurement of gene expression ratios using spotted cDNA microarrays

    PubMed Central

    2006-01-01

    Background Spotted cDNA microarrays generally employ co-hybridization of fluorescently-labeled RNA targets to produce gene expression ratios for subsequent analysis. Direct comparison of two RNA samples in the same microarray provides the highest level of accuracy; however, due to the number of combinatorial pair-wise comparisons, the direct method is impractical for studies including large number of individual samples (e.g., tumor classification studies). For such studies, indirect comparisons using a common reference standard have been the preferred method. Here we evaluated the precision and accuracy of reconstructed ratios from three indirect methods relative to ratios obtained from direct hybridizations, herein considered as the gold-standard. Results We performed hybridizations using a fixed amount of Cy3-labeled reference oligonucleotide (RefOligo) against distinct Cy5-labeled targets from prostate, breast and kidney tumor samples. Reconstructed ratios between all tissue pairs were derived from ratios between each tissue sample and RefOligo. Reconstructed ratios were compared to (i) ratios obtained in parallel from direct pair-wise hybridizations of tissue samples, and to (ii) reconstructed ratios derived from hybridization of each tissue against a reference RNA pool (RefPool). To evaluate the effect of the external references, reconstructed ratios were also calculated directly from intensity values of single-channel (One-Color) measurements derived from tissue sample data collected in the RefOligo experiments. We show that the average coefficient of variation of ratios between intra- and inter-slide replicates derived from RefOligo, RefPool and One-Color were similar and 2 to 4-fold higher than ratios obtained in direct hybridizations. Correlation coefficients calculated for all three tissue comparisons were also similar. In addition, the performance of all indirect methods in terms of their robustness to identify genes deemed as differentially expressed

  18. Evaluation of georeferencing methods with respect to their suitability to address unsimilarity between the image to be referenced and the reference image

    NASA Astrophysics Data System (ADS)

    Brüstle, Stefan; Erdnüß, Bastian

    2016-10-01

    In recent years, operational costs of unmanned aircraft systems (UAS) have been massively decreasing. New sensors satisfying weight and size restrictions of even small UAS cover many different spectral ranges and spatial resolutions. This results in airborne imagery having become more and more available. Such imagery is used to address many different tasks in various fields of application. For many of those tasks, not only the content of the imagery itself is of interest, but also its spatial location. This requires the imagery to be properly georeferenced. Many UAS have an integrated GPS receiver together with some kind of INS device acquiring the sensor orientation to provide the georeference. However, both GPS and INS data can easily become unavailable for a period of time during a flight, e.g. due to sensor malfunction, transmission problems or jamming. Imagery gathered during such times lacks georeference. Moreover, even in datasets not affected by such problems, GPS and INS inaccuracies together with a potentially poor knowledge of ground elevation can render location information accuracy less than sufficient for a given task. To provide or improve the georeference of an image affected by this, an image to reference registration can be performed if a suitable reference is available, e.g. a georeferenced orthophoto covering the area of the image to be georeferenced. Registration and thus georeferencing is achieved by determining a transformation between the image to be referenced and the reference which maximizes the coincidence of relevant structures present both in the former and the latter. Many methods have been developed to accomplish this task. Regardless of their differences they usually tend to perform the better the more similar an image and a reference are in appearance. This contribution evaluates a selection of such methods all differing in the type of structure they use for the assessment of coincidence with respect to their ability to tolerate

  19. Ready Reference.

    ERIC Educational Resources Information Center

    Koltay, Emery

    1999-01-01

    Includes the following ready reference information: "Publishers' Toll-Free Telephone Numbers"; "How to Obtain an ISBN (International Standard Book Number)"; "How to Obtain an ISSN (International Standard Serial Number)"; and "How to Obtain an SAN (Standard Address Number)". (AEF)

  20. 48 CFR 317.7002 - Potential multi-agency and intra-agency sources.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Potential multi-agency and intra-agency sources. 317.7002 Section 317.7002 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES CONTRACTING METHODS AND CONTRACT TYPES SPECIAL CONTRACTING METHODS Multi-agency and Intra-agency Contracts 317.7002 Potential...

  1. Continuous improvement of medical test reliability using reference methods and matrix-corrected target values in proficiency testing schemes: application to glucose assay.

    PubMed

    Delatour, Vincent; Lalere, Beatrice; Saint-Albin, Karène; Peignaux, Maryline; Hattchouel, Jean-Marc; Dumont, Gilles; De Graeve, Jacques; Vaslin-Reimann, Sophie; Gillery, Philippe

    2012-11-20

    The reliability of biological tests is a major issue for patient care in terms of public health that involves high economic stakes. Reference methods, as well as regular external quality assessment schemes (EQAS), are needed to monitor the analytical performance of field methods. However, control material commutability is a major concern to assess method accuracy. To overcome material non-commutability, we investigated the possibility of using lyophilized serum samples together with a limited number of frozen serum samples to assign matrix-corrected target values, taking the example of glucose assays. Trueness of the current glucose assays was first measured against a primary reference method by using human frozen sera. Methods using hexokinase and glucose oxidase with spectroreflectometric detection proved very accurate, with bias ranging between -2.2% and +2.3%. Bias of methods using glucose oxidase with spectrophotometric detection was +4.5%. Matrix-related bias of the lyophilized materials was then determined and ranged from +2.5% to -14.4%. Matrix-corrected target values were assigned and used to assess trueness of 22 sub-peer groups. We demonstrated that matrix-corrected target values can be a valuable tool to assess field method accuracy in large scale surveys where commutable materials are not available in sufficient amount with acceptable costs.

  2. In-vivo assessment of tissue metabolite levels using 1H MRS and the Electric REference To access In vivo Concentrations (ERETIC) method.

    PubMed

    Heinzer-Schweizer, S; De Zanche, N; Pavan, M; Mens, G; Sturzenegger, U; Henning, A; Boesiger, P

    2010-05-01

    Quantitative values of metabolite concentrations in (1)H magnetic resonance spectroscopy have been obtained using the Electric REference To access In vivo Concentrations (ERETIC) method, whereby a synthetic reference signal is injected during the acquisition of spectra. The method has been improved to enable quantification of metabolite concentrations in vivo. Optical signal transmission was used to eliminate random fluctuations in ERETIC signal coupling to the receiver coil due to changes in position of cables and highly dielectric human tissue. Stability and reliability of the signal were tested in vitro, achieving stability with a mean error of 2.83%. Scaling of the signal in variable loading conditions was demonstrated and in-vivo measurements of brain were acquired on a 3T Philips system using a transmit/receive coil. The quantitative brain water and metabolite concentration values are in good agreement with those in the literature.

  3. Evaluation of a new electronic preoperative reference marker for toric intraocular lens implantation by two different methods of analysis: Adobe Photoshop versus iTrace

    PubMed Central

    Farooqui, Javed Hussain; Sharma, Mansi; Koul, Archana; Dutta, Ranjan; Shroff, Noshir Minoo

    2017-01-01

    PURPOSE: The aim of this study is to compare two different methods of analysis of preoperative reference marking for toric intraocular lens (IOL) after marking with an electronic marker. SETTING/VENUE: Cataract and IOL Implantation Service, Shroff Eye Centre, New Delhi, India. PATIENTS AND METHODS: Fifty-two eyes of thirty patients planned for toric IOL implantation were included in the study. All patients had preoperative marking performed with an electronic preoperative two-step toric IOL reference marker (ASICO AE-2929). Reference marks were placed at 3-and 9-o'clock positions. Marks were analyzed with two systems. First, slit-lamp photographs taken and analyzed using Adobe Photoshop (version 7.0). Second, Tracey iTrace Visual Function Analyzer (version 5.1.1) was used for capturing corneal topograph examination and position of marks noted. Amount of alignment error was calculated. RESULTS: Mean absolute rotation error was 2.38 ± 1.78° by Photoshop and 2.87 ± 2.03° by iTrace which was not statistically significant (P = 0.215). Nearly 72.7% of eyes by Photoshop and 61.4% by iTrace had rotation error ≤3° (P = 0.359); and 90.9% of eyes by Photoshop and 81.8% by iTrace had rotation error ≤5° (P = 0.344). No significant difference in absolute amount of rotation between eyes when analyzed by either method. CONCLUSIONS: Difference in reference mark positions when analyzed by two systems suggests the presence of varying cyclotorsion at different points of time. Both analysis methods showed an approximately 3° of alignment error, which could contribute to 10% loss of astigmatic correction of toric IOL. This can be further compounded by intra-operative marking errors and final placement of IOL in the bag. PMID:28757694

  4. Evaluation of the PREVI® Isola automated seeder system compared to reference manual inoculation for antibiotic susceptibility testing by the disk diffusion method.

    PubMed

    Le Page, S; van Belkum, A; Fulchiron, C; Huguet, R; Raoult, D; Rolain, J-M

    2015-09-01

    The disk diffusion (DD) method remains the most popular manual technique for antibiotic susceptibility testing (AST) in clinical microbiology laboratories. This is because of its simplicity, reproducibility, and limited cost compared to (automated) microdilution systems, which are usually less sensitive at detecting certain important mechanisms of resistance. Here, we evaluate the PREVI® Isola automated seeder system using a new protocol for spreading bacterial suspensions (eight deposits of calibrated inocula of bacteria, followed by two rounds of rotation) in comparison with manual DD reference testing on a large series of clinical and reference strains. The average time required for seeding one agar plate for DD with this new protocol was 51 s per plate, i.e., 70 agar plates/h. Reproducibility and repeatability was assessed on three reference and three randomly chosen clinical strains, as usually requested by the European Committee on Antimicrobial Susceptibility Testing (EUCAST), and was excellent compared to the manual method. The standard deviations of zones of growth inhibition showed no statistical discrimination. The correlation between the two methods, assessed using 294 clinical isolates and a panel of six antibiotics (n = 3,528 zones of growth inhibition measured), was excellent, with a correlation coefficient of 0.977. The new PREVI® Isola protocol adapted for DD had a sensitivity of 99 % and a specificity of 100 % compared to the manual technique for interpreting DD as recommended by the EUCAST.

  5. Single-laboratory evaluation and modification of US EPA (Environmental Protection Agency) Methods 7470 and 7471 for the determination of mercury in aqueous and solid hazardous wastes (journal version)

    SciTech Connect

    Churchwell, M.E.; Livingston, R.L.; Sgontz, D.L.; Messman, J.D.; Beckert, W.F.

    1988-01-01

    The current U.S. Environmental Protection Agency (U.S. EPA) protocols for mercury determinations in aqueous and solid-waste samples (SW-846 Methods 7470 and 7471) using recirculating cold-vapor atomic absorption spectrometry (CV-AAS) were evaluated. The U.S. EPA protocols have been modified in a single-laboratory study to facilitate additional QC measures, to enhance detectability for low-level mercury concentrations, and to eliminate nonspecific vapor-absorption interferences. Volumetric manipulations for additional QC measures, if required, are facilitated by performing the sample digestions in Erlenmeyer flasks rather than in the current Biochemical Oxygen Demand (BOD) reduction-aeration bottles. Instrument detectability is improved 10-fold by using a gas sparging bottle as a dedicated reduction-aeration vessel and a silver wool-amalgamation CV-AAS system operated in an open configuration. The on-line amalgamation thermal-desorption process of the modified CV-AAS system eliminates interfering water and organic matrix vapors prior to the mercury absorption measurement. Good accuracy and precision have been obtained with the amalgamation CV-AAS system for the analyses of four reference sediment materials.

  6. LC-MS candidate reference methods for the harmonisation of parathyroid hormone (PTH) measurement: a review of recent developments and future considerations.

    PubMed

    Couchman, Lewis; Taylor, David R; Krastins, Bryan; Lopez, Mary F; Moniz, Cajetan F

    2014-09-01

    The analysis of intact parathyroid hormone (PTH) (PTH1-84) is useful in the diagnosis of hyper- and hypocalcaemia, hyperparathyroidism, and in the prevention of bone mineral disorders in renal patients. The analysis is complicated by the presence of PTH fragments, which may accumulate in renal failure and cross-react in immunoassays, including the most recent third-generation immunoassays. Large variability exists between different commercially available assays. This article reviews the current literature on PTH testing, with emphasis on the use of mass spectrometry-based methods, and considers the important sources of variation which still need to be addressed prior to the development of much needed candidate reference methods for PTH analysis. Recently, mass spectrometric methods have been developed for the quantitation of PTH1-84 using surrogate tryptic peptides, but even these methods are subject to significant interferences due to the presence of newly observed modified PTH species, such as oxidised and phosphorylated PTH variants, which can accumulate in patient samples. Further work, including: 1) the use of high-resolution mass spectrometry; and 2) the analysis of PTH without prior protease digestion, is required before these approaches can be considered as reference methods against which other methods should be harmonised.

  7. Linking in situ LAI and fine resolution remote sensing data to map reference LAI over cropland and grassland using geostatistical regression method

    NASA Astrophysics Data System (ADS)

    He, Yaqian; Bo, Yanchen; Chai, Leilei; Liu, Xiaolong; Li, Aihua

    2016-08-01

    Leaf Area Index (LAI) is an important parameter of vegetation structure. A number of moderate resolution LAI products have been produced in urgent need of large scale vegetation monitoring. High resolution LAI reference maps are necessary to validate these LAI products. This study used a geostatistical regression (GR) method to estimate LAI reference maps by linking in situ LAI and Landsat TM/ETM+ and SPOT-HRV data over two cropland and two grassland sites. To explore the discrepancies of employing different vegetation indices (VIs) on estimating LAI reference maps, this study established the GR models for different VIs, including difference vegetation index (DVI), normalized difference vegetation index (NDVI), and ratio vegetation index (RVI). To further assess the performance of the GR model, the results from the GR and Reduced Major Axis (RMA) models were compared. The results show that the performance of the GR model varies between the cropland and grassland sites. At the cropland sites, the GR model based on DVI provides the best estimation, while at the grassland sites, the GR model based on DVI performs poorly. Compared to the RMA model, the GR model improves the accuracy of reference LAI maps in terms of root mean square errors (RMSE) and bias.

  8. Metallurgical and chemical characterization of copper alloy reference materials within laser ablation inductively coupled plasma mass spectrometry: Method development for minimally-invasive analysis of ancient bronze objects

    NASA Astrophysics Data System (ADS)

    Walaszek, Damian; Senn, Marianne; Faller, Markus; Philippe, Laetitia; Wagner, Barbara; Bulska, Ewa; Ulrich, Andrea

    2013-01-01

    The chemical composition of ancient metal objects provides important information for manufacturing studies and authenticity verification of ancient copper or bronze artifacts. Non- or minimal-destructive analytical methods are preferred to mitigate visible damage. Laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) enables the determination of major elements as well as impurities down to lower ppm-levels, however, accuracy and precision of analysis strongly depend on the homogeneity of reference materials used for calibration. Moreover, appropriate analytical procedures are required e.g. in terms of ablation strategies (scan mode, spot size, etc.). This study reviews available copper alloy (certified) reference materials — (C)RMs from different sources and contributes new metallurgical data on homogeneity and spatial elemental distribution. Investigations of the standards were performed by optical and scanning electron microscopy with X-ray spectrometry (SEM-EDX) for the following copper alloy and bronze (certified) reference materials: NIST 454, BAM 374, BAM 211, BAM 227, BAM 374, BAM 378, BAS 50.01-2, BAS 50.03-4, and BAS 50.04-4. Additionally, the influence of inhomogeneities on different ablation and calibration strategies is evaluated to define an optimum analytical strategy in terms of line scan versus single spot ablation, variation of spot size, selection of the most appropriate RMs or minimum number of calibration reference materials.

  9. The history of the microsphere method for measuring blood flows with special reference to myocardial blood flow: a personal memoir.

    PubMed

    Hoffman, Julien I E

    2017-04-01

    We use many types of equipment and technologies to make our measurements but give little thought to how they developed. Evolution was once described as a series of recoils from blind alleys, and this is exemplified by the gradual development of the microsphere method of measuring blood flows. The microsphere method is one of the most frequently used methods for measuring blood flow to organs and portions of organs. The method can measure myocardial blood flow with reasonable accuracy (within 10%) down to samples weighing >50 mg but probably will not do so for samples weighing 1-10 mg. Microspheres with diameters from 10 to 15 μm provide the best compromise between accurate flow measurement and retention in tissue. Radioactive labels have been almst entirely replaced by fluorescent labels, but colored microspheres and neutron-activated labels are also used.NEW & NOTEWORTHY The contributions of the various individuals who developed the microsphere method of measuring regional blood flows and how these advances took place are brought to light in this paper.

  10. Bracketing method with certified reference materials for high precision and accuracy determination of trace cadmium in drinking water by Inductively Coupled Plasma - Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Ketrin, Rosi; Handayani, Eka Mardika; Komalasari, Isna

    2017-01-01

    Two significant parameters to evaluate the measurement results are known as precision and accuracy. Both are associated with indeterminate and determinate error, respectively, that normally happen in such spectrometric measurement method as Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). These errors must be eliminated or suppressed to get high precision and accuracy of the method. Decreasing the errors thus increasing the precision and accuracy of the method. In this study, bracketing method using two-point standard calibration was proposed in order to suppress the indeterminate error caused by instrumental drift thus increasing the result precision, and applied for measuring cadmium in drinking water samples. Certified reference material of ERM CA011b-Hard drinking water UK-metals was used to know the determinate error or measurement bias. When bias is obtained, some corrections are needed to get the accurate measurement result. The result was compared to that by external calibration method.

  11. Further work on the cryopreservation of articular cartilage with particular reference to the liquidus tracking (LT) method.

    PubMed

    Wang, Lihong; Pegg, David E; Lorrison, Jonathan; Vaughan, David; Rooney, Paul

    2007-10-01

    The cryopreservation of articular cartilage with survival of living cells has been a difficult problem. We have provided evidence that this is due to the formation of ice crystals in the chondrons. We have developed a method in which the concentration of the cryoprotectant dimethyl sulphoxide (Me(2)SO) is increased progressively, in steps, as cooling proceeds so that ice is never allowed to form, but the very high concentrations of Me(2)SO required at low temperatures are reached only at those low temperatures. In this paper, we describe some new experiments with discs of ovine articular cartilage similar to those used in our previous studies and we show that continuous stirring throughout the process resulted in a significant increase in the rate of (35)S sulphate incorporation into glycosoaminoglycans (GAGs), now reaching 87% of the corresponding fresh control values. We confirmed that the method is also effective for human knee joint cartilage, which gave 70% of fresh control ability to synthesise GAGs; continuous stirring was also used in this experiment. We then extended the method to ovine knee joint osteochondral dowels and showed that, again with continuous stirring, the method produced tissue concentrations of Me(2)SO that were sufficient to prevent freezing in dowels too, and to permit cell function at 60% of control. The most important mechanical property (instantaneous compressive modulus) was unaffected by the process. Finally, we experimented with some technical variations to facilitate clinical use-a more rapid process for warming and removal of Me(2)SO was developed and a method of short-term storage before or after cryopreservation was developed. Finally, pilot experiments were carried out to provide proof of principle for a closed, continuous flow method in which both temperature and Me(2)SO concentration were computer-controlled.

  12. Automated anthropometric phenotyping with novel Kinect-based three-dimensional imaging method: comparison with a reference laser imaging system.

    PubMed

    Soileau, L; Bautista, D; Johnson, C; Gao, C; Zhang, K; Li, X; Heymsfield, S B; Thomas, D; Zheng, J

    2016-04-01

    Anthropometry for measuring body composition, shape, surface area and volume is important for human clinical research and practice. Although training and technical skills are required for traditional tape and caliper anthropometry, a new opportunity exists for automated measurement using newly developed relatively low-cost three-dimensional (3D) imaging devices. The aim of this study was to compare results provided by a Kinect-based device to a traditional laser 3D reference system. Measurements made by the evaluated device, a hybrid of commercially purchased hardware (KX-16; TC(2), Cary, NC, USA) with our additional added software, were compared with those derived by a high-resolution laser scanner (Vitus Smart XXL; Human Solutions North America, Cary, NC, USA). Both imaging systems were compared with additional linear (stadiometer-derived height) and volumetric (total volume, air-displacement plethysmography) measurements. Subjects (n=101) were healthy children (age ≥5 years) and adults varying in body mass index. Representative linear (4), circumferential (6), volumetric (3) and surface area (1) measurements made by the Kinect-based device showed a consistent pattern relative to the laser system: high correlations (R(2)s= 0.70-0.99, all P<0.001); 1-3% differences for large linear (for example, height, X±s.d., -1.4±0.5%), circumferential (for example, waist circumference, -2.1±1.8%), volume (for example, total body, -0.8±2.2%) and surface area (whole-body, -1.7±2.0%) estimates. By contrast, mean measurement differences were substantially larger for small structures (for example, forearm volume, 31.3±31.4%). Low-cost 3D Kinect-based imaging systems have the potential for providing automated accurate anthropometric and related body measurements for relatively large components; further hardware and software developments may be able to improve system small-component resolution.

  13. Why do women not return family history forms when referred to breast cancer genetics services? A mixed-method study.

    PubMed

    Hanning, Kirstie A; Steel, Michael; Goudie, David; McLeish, Lorna; Dunlop, Jackie; Myring, Jessica; Sullivan, Frank; Berg, Jonathan; Humphris, Gerry; Ozakinci, Gozde

    2015-10-01

    Personal and family data forms, completed by women referred to breast cancer genetics clinics, are valuable tools for verification and extension of family history, crucial steps in accurate risk evaluation. A significant minority of women do not complete and return these forms, despite reminders, even when completion is a pre-requisite for a clinic appointment. To facilitate access of women at increased familial risk of breast cancer to screening and counselling services by investigating reasons for non-return of the forms. Based on a single regional 'breast cancer family' service in the UK, Analysis of quantitative data comparing women who did not return forms (n = 55) with those who had done so (n = 59), together with qualitative evaluation of potential barriers to form-completion through semi-structured telephone interviews with a random subset of 'non-returners' (n = 23). Non-returners have higher proportions of the very young (below the age at which surveillance could be offered) and of women from lower social deprivation categories. Interviews revealed that the majority of non-returners are anxious, rather than unconcerned about their breast cancer risk and circumstances and attitudes contributed to non-compliance. Twenty-one participants confirmed that they would welcome an appointment at a 'breast cancer family' clinic, but nine did not attend for the appointment. They were significantly younger than those who attend, but were not at lower familial risk. Many women who fail to complete and return a family history form would benefit from risk assessment and genetic counselling. Several steps are suggested that might help them access the relevant services. © 2014 John Wiley & Sons Ltd.

  14. Parametric quantification of myocardial ischaemia using real-time perfusion adenosine stress echocardiography images, with SPECT as reference method.

    PubMed

    Gudmundsson, P; Shahgaldi, K; Winter, R; Dencker, M; Kitlinski, M; Thorsson, O; Ljunggren, L; Willenheimer, R

    2010-01-01

    Real-time perfusion (RTP) adenosine stress echocardiography (ASE) can be used to visually evaluate myocardial ischaemia. The RTP power modulation technique, provides images for off-line parametric perfusion quantification using Qontrast software. From replenishment curves, this generates parametric images of peak signal intensity (A), myocardial blood flow velocity (beta) and myocardial blood flow (Axbeta) at rest and stress. This may be a tool for objective myocardial ischaemia evaluation. We assessed myocardial ischaemia by RTP-ASE Qontrast((R))-generated images, using 99mTc-tetrofosmin single-photon emission computed tomography (SPECT) as reference. Sixty-seven patients admitted to SPECT underwent RTP-ASE (SONOS 5500) during Sonovue infusion, before and throughout adenosine stress, also used for SPECT. Quantitative off-line analyses of myocardial perfusion by RTP-ASE Qontrast-generated A, beta and Axbeta images, at different time points during rest and stress, were blindly compared to SPECT. We analysed 201 coronary territories [corresponding to the left anterior descendent (LAD), left circumflex (LCx) and right coronary (RCA) arteries] from 67 patients. SPECT showed ischaemia in 18 patients. Receiver operator characteristics and kappa values showed that A, beta and Axbeta image interpretation significantly identified ischaemia in all territories (area under the curve 0.66-0.80, P = 0.001-0.05). Combined A, beta and Axbeta image interpretation gave the best results and the closest agreement was seen in the LAD territory: 89% accuracy; kappa 0.63; P<0.001. Myocardial isachemia can be evaluated in the LAD territory using RTP-ASE Qontrast-generated images, especially by combined A, beta and Axbeta image interpretation. However, the technique needs improvements regarding the LCx and RCA territories.

  15. Evaluation of a new electronic preoperative reference marker for toric intraocular lens implantation by two different methods of analysis: Adobe Photoshop versus iTrace.

    PubMed

    Farooqui, Javed Hussain; Sharma, Mansi; Koul, Archana; Dutta, Ranjan; Shroff, Noshir Minoo

    2017-01-01

    The aim of this study is to compare two different methods of analysis of preoperative reference marking for toric intraocular lens (IOL) after marking with an electronic marker. Cataract and IOL Implantation Service, Shroff Eye Centre, New Delhi, India. Fifty-two eyes of thirty patients planned for toric IOL implantation were included in the study. All patients had preoperative marking performed with an electronic preoperative two-step toric IOL reference marker (ASICO AE-2929). Reference marks were placed at 3-and 9-o'clock positions. Marks were analyzed with two systems. First, slit-lamp photographs taken and analyzed using Adobe Photoshop (version 7.0). Second, Tracey iTrace Visual Function Analyzer (version 5.1.1) was used for capturing corneal topograph examination and position of marks noted. Amount of alignment error was calculated. Mean absolute rotation error was 2.38 ± 1.78° by Photoshop and 2.87 ± 2.03° by iTrace which was not statistically significant (P = 0.215). Nearly 72.7% of eyes by Photoshop and 61.4% by iTrace had rotation error ≤3° (P = 0.359); and 90.9% of eyes by Photoshop and 81.8% by iTrace had rotation error ≤5° (P = 0.344). No significant difference in absolute amount of rotation between eyes when analyzed by either method. Difference in reference mark positions when analyzed by two systems suggests the presence of varying cyclotorsion at different points of time. Both analysis methods showed an approximately 3° of alignment error, which could contribute to 10% loss of astigmatic correction of toric IOL. This can be further compounded by intra-operative marking errors and final placement of IOL in the bag.

  16. Alignment of gene expression profiles from test samples against a reference database: New method for context-specific interpretation of microarray data

    PubMed Central

    2011-01-01

    Background Gene expression microarray data have been organized and made available as public databases, but the utilization of such highly heterogeneous reference datasets in the interpretation of data from individual test samples is not as developed as e.g. in the field of nucleotide sequence comparisons. We have created a rapid and powerful approach for the alignment of microarray gene expression profiles (AGEP) from test samples with those contained in a large annotated public reference database and demonstrate here how this can facilitate interpretation of microarray data from individual samples. Methods AGEP is based on the calculation of kernel density distributions for the levels of expression of each gene in each reference tissue type and provides a quantitation of the similarity between the test sample and the reference tissue types as well as the identity of the typical and atypical genes in each comparison. As a reference database, we used 1654 samples from 44 normal tissues (extracted from the Genesapiens database). Results Using leave-one-out validation, AGEP correctly defined the tissue of origin for 1521 (93.6%) of all the 1654 samples in the original database. Independent validation of 195 external normal tissue samples resulted in 87% accuracy for the exact tissue type and 97% accuracy with related tissue types. AGEP analysis of 10 Duchenne muscular dystrophy (DMD) samples provided quantitative description of the key pathogenetic events, such as the extent of inflammation, in individual samples and pinpointed tissue-specific genes whose expression changed (SAMD4A) in DMD. AGEP analysis of microarray data from adipocytic differentiation of mesenchymal stem cells and from normal myeloid cell types and leukemias provided quantitative characterization of the transcriptomic changes during normal and abnormal cell differentiation. Conclusions The AGEP method is a widely applicable method for the rapid comprehensive interpretation of microarray data, as

  17. Stable isotope analyses of oxygen (18O:17O:16O) and chlorine (37Cl:35Cl) in perchlorate: reference materials, calibrations, methods, and interferences

    USGS Publications Warehouse

    Böhlke, John Karl; Mroczkowski, Stanley J.; Sturchio, Neil C.; Heraty, Linnea J.; Richman, Kent W.; Sullivan, Donald B.; Griffith, Kris N.; Gu, Baohua; Hatzinger, Paul B.

    2017-01-01

    RationalePerchlorate (ClO4−) is a common trace constituent of water, soils, and plants; it has both natural and synthetic sources and is subject to biodegradation. The stable isotope ratios of Cl and O provide three independent quantities for ClO4− source attribution and natural attenuation studies: δ37Cl, δ18O, and δ17O (or Δ17O or 17Δ) values. Documented reference materials, calibration schemes, methods, and interferences will improve the reliability of such studies.MethodsThree large batches of KClO4 with contrasting isotopic compositions were synthesized and analyzed against VSMOW-SLAP, atmospheric O2, and international nitrate and chloride reference materials. Three analytical methods were tested for O isotopes: conversion of ClO4− to CO for continuous-flow IRMS (CO-CFIRMS), decomposition to O2 for dual-inlet IRMS (O2-DIIRMS), and decomposition to O2 with molecular-sieve trap (O2-DIIRMS+T). For Cl isotopes, KCl produced by thermal decomposition of KClO4 was reprecipitated as AgCl and converted into CH3Cl for DIIRMS.ResultsKClO4 isotopic reference materials (USGS37, USGS38, USGS39) represent a wide range of Cl and O isotopic compositions, including non-mass-dependent O isotopic variation. Isotopic fractionation and exchange can affect O isotope analyses of ClO4− depending on the decomposition method. Routine analyses can be adjusted for such effects by normalization, using reference materials prepared and analyzed as samples. Analytical errors caused by SO42−, NO3−, ReO42−, and C-bearing contaminants include isotope mixing and fractionation effects on CO and O2, plus direct interference from CO2 in the mass spectrometer. The results highlight the importance of effective purification of ClO4− from environmental samples.ConclusionsKClO4 reference materials are available for testing methods and calibrating isotopic data for ClO4− and other substances with widely varying Cl or O isotopic compositions. Current ClO4−extraction, purification

  18. 40 CFR Appendix B to Part 50 - Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... conveniently. c. Preclude leaks that would cause error in the measurement of the air volume passing through the... method provides a measurement of the mass concentration of total suspended particulate matter (TSP) in... standards for particulate matter as specified in § 50.6 and § 50.7 of this chapter. The measurement...

  19. PERFORMANCE AND SENSITIVITY ANALYSIS OF THE USEPA WINS FRACTIONATOR FOR THE PM 2.5 FEDERAL REFERENCE METHOD

    EPA Science Inventory

    In response to growing health concerns related to atmospheric fine particles, EPA promulgated in 1997 a new particulate matter standard accompanied by new sampling methodology. Based on a review of pertinent literature, a new metric (PM;,) was adopted and its measurement method...

  20. PERFORMANCE AND SENSITIVITY ANALYSIS OF THE USEPA WINS FRACTIONATOR FOR THE PM 2.5 FEDERAL REFERENCE METHOD

    EPA Science Inventory

    In response to growing health concerns related to atmospheric fine particles, EPA promulgated in 1997 a new particulate matter standard accompanied by new sampling methodology. Based on a review of pertinent literature, a new metric (PM;,) was adopted and its measurement method...

  1. Earthquake early warning for the 2016 Kumamoto earthquake: performance evaluation of the current system and the next-generation methods of the Japan Meteorological Agency

    NASA Astrophysics Data System (ADS)

    Kodera, Yuki; Saitou, Jun; Hayashimoto, Naoki; Adachi, Shimpei; Morimoto, Masahiko; Nishimae, Yuji; Hoshiba, Mitsuyuki

    2016-12-01

    The 2016 Kumamoto earthquake (Kumamoto earthquake sequence) is an extremely high-seismicity event that has been occurring across Kumamoto and Oita Prefectures in Japan since April 14, 2016 (JST). The earthquake early warning system of the Japan Meteorological Agency (JMA) issued warnings for 19 events in the Kumamoto earthquake sequence from April 14 to 19, under some of the heaviest loading conditions since the system began operating in 2007. We analyzed the system performance for cases where a warning was issued and/or strong motion was actually observed. The results indicated that the system exhibited remarkable performance, especially for the most destructive earthquakes in the Kumamoto earthquake sequence. In addition, the system did not miss or seriously under-predict strong motion of any large earthquake from April 14 to 30. However, in four cases, the system issued over-predicted warnings due to the simultaneous occurrence of small earthquakes within a short distance, which implies a fundamental obstacle in trigger-data classifications based solely on arrival time. We also performed simulations using the integrated particle filter (IPF) and propagation of local undamped motion (PLUM) methods, which JMA plans to implement to address over-prediction for multiple simultaneous earthquakes and under-prediction for massive earthquakes with large rupture zones. The simulation results of the IPF method indicated that the IPF method is highly effective at minimizing over-prediction even for multiple simultaneous earthquakes within a short distance, since it adopts a trigger-data classification using velocity amplitude and hypocenter determinations using not-yet-arrived data. The simulation results of the PLUM method demonstrated that the PLUM method is capable of issuing warnings for destructive inland earthquakes more rapidly than the current system owing to the use of additional seismometers that can only be incorporated by this method.[Figure not available: see

  2. An improved method for dynamic measurement of deflections of the vertical based on the maintenance of attitude reference.

    PubMed

    Dai, Dongkai; Wang, Xingshu; Zhan, Dejun; Huang, Zongsheng

    2014-09-03

    A new method for dynamic measurement of deflections of the vertical (DOV) is proposed in this paper. The integration of an inertial navigation system (INS) and global navigation satellite system (GNSS) is constructed to measure the body's attitude with respect to the astronomical coordinates. Simultaneously, the attitude with respect to the geodetic coordinates is initially measured by a star sensor under quasi-static condition and then maintained by the laser gyroscope unit (LGU), which is composed of three gyroscopes in the INS, when the vehicle travels along survey lines. Deflections of the vertical are calculated by using the difference between the attitudes with respect to the geodetic coordinates and astronomical coordinates. Moreover, an algorithm for removing the trend error of the vertical deflections is developed with the aid of Earth Gravitational Model 2008 (EGM2008). In comparison with traditional methods, the new method required less accurate GNSS, because the dynamic acceleration calculation is avoided. The errors of inertial sensors are well resolved in the INS/GNSS integration, which is implemented by a Rauch-Tung-Striebel (RTS) smoother. In addition, a single-axis indexed INS is adopted to improve the observability of the system errors and to restrain the inertial sensor errors. The proposed method is validated by Monte Carlo simulations. The results show that deflections of the vertical can achieve a precision of better than 1″ for a single survey line. The proposed method can be applied to a gravimetry system based on a ground vehicle or ship with a speed lower than 25 m/s.

  3. An Improved Method for Dynamic Measurement of Deflections of the Vertical Based on the Maintenance of Attitude Reference

    PubMed Central

    Dai, Dongkai; Wang, Xingshu; Zhan, Dejun; Huang, Zongsheng

    2014-01-01

    A new method for dynamic measurement of deflections of the vertical (DOV) is proposed in this paper. The integration of an inertial navigation system (INS) and global navigation satellite system (GNSS) is constructed to measure the body's attitude with respect to the astronomical coordinates. Simultaneously, the attitude with respect to the geodetic coordinates is initially measured by a star sensor under quasi-static condition and then maintained by the laser gyroscope unit (LGU), which is composed of three gyroscopes in the INS, when the vehicle travels along survey lines. Deflections of the vertical are calculated by using the difference between the attitudes with respect to the geodetic coordinates and astronomical coordinates. Moreover, an algorithm for removing the trend error of the vertical deflections is developed with the aid of Earth Gravitational Model 2008 (EGM2008). In comparison with traditional methods, the new method required less accurate GNSS, because the dynamic acceleration calculation is avoided. The errors of inertial sensors are well resolved in the INS/GNSS integration, which is implemented by a Rauch–Tung–Striebel (RTS) smoother. In addition, a single-axis indexed INS is adopted to improve the observability of the system errors and to restrain the inertial sensor errors. The proposed method is validated by Monte Carlo simulations. The results show that deflections of the vertical can achieve a precision of better than 1″ for a single survey line. The proposed method can be applied to a gravimetry system based on a ground vehicle or ship with a speed lower than 25 m/s. PMID:25192311

  4. TANK OPERATIONS CONTRACT CONSTRUCTION MANAGEMENT METHODOLOGY UTILIZING THE AGENCY METHOD OF CONSTRUCTION MANAGEMENT TO SAFELY AND EFFECTIVELY COMPLETE NUCLEAR CONSTRUCTION WORK

    SciTech Connect

    LESO KF; HAMILTON HM; FARNER M; HEATH T

    2010-01-14

    Washington River Protection Solutions, LLC (WRPS) has faced significant project management challenges in managing Davis-Bacon construction work that meets contractually required small business goals. The unique challenge is to provide contracting opportunities to multiple small business construction subcontractors while performing high hazard work in a safe and productive manner. Previous to the Washington River Protection Solutions, LLC contract, Construction work at the Hanford Tank Farms was contracted to large companies, while current Department of Energy (DOE) Contracts typically emphasize small business awards. As an integral part of Nuclear Project Management at Hanford Tank Farms, construction involves removal of old equipment and structures and installation of new infrastructure to support waste retrieval and waste feed delivery to the Waste Treatment Plant. Utilizing the optimum construction approach ensures that the contractors responsible for this work are successful in meeting safety, quality, cost and schedule objectives while working in a very hazardous environment. This paper describes the successful transition from a traditional project delivery method that utilized a large business general contractor and subcontractors to a new project construction management model that is more oriented to small businesses. Construction has selected the Agency Construction Management Method. This method was implemented in the first quarter of Fiscal Year (FY) 2009, where Construction Management is performed by substantially home office resources from the URS Northwest Office in Richland, Washington. The Agency Method has allowed WRPS to provide proven Construction Managers and Field Leads to mentor and direct small business contractors, thus providing expertise and assurance of a successful project. Construction execution contracts are subcontracted directly by WRPS to small or disadvantaged contractors that are mentored and supported by DRS personnel. Each small

  5. Exploring the characteristics of nursing agencies in South Africa.

    PubMed

    Olojede, Omolola I; Rispel, Laetitia C

    2015-01-01

    Background Nursing agencies are temporary employment service providers or labour brokers that supply nurses to health establishments. Objective This study was conducted to determine the characteristics of nursing agencies and their relationship with clients in the health sector. Methods During 2011, a cross-sectional national survey of 106 nursing agencies was conducted. After obtaining informed consent, telephone interviews were conducted with a representative of the selected nursing agency using a pretested structured questionnaire. Questions focused on the following: ownership, date of establishment, province of operation, distribution of clients across private and public health facilities; existence of a code of conduct; nature of the contractual relationship between nursing agencies and their clients, and numbers and cadres of nurses contracted. The survey data were analysed using STATA® 12. Results Fifty-two nursing agencies participated in the survey, representing a 49% response rate. The study found that 32 nursing agencies (62%) served private-sector clients only, which included private hospitals, homes for elderly people, patients in private homes, and private industry/company clinics, and only four (8%) of the agencies served the public sector only. Twenty-seven percent of nursing agencies provided services to homes for elderly individuals. Nursing agencies were more likely to have contracts with private-sector clients (84%) than with public-sector clients (16%) (p = 0.04). Although 98% of nursing agencies reported that they had a code of conduct, the proportion was higher for private-sector clients (73%) compared to public-sector clients (27%). In terms of quality checks and monitoring, 81% of agencies agreed with a statement that they checked the nursing council registration of nurses, 82% agreed with a statement that they requested certified copies of a nurse's qualifications. Only 21% indicated that they conducted reference checks of nurses with

  6. Exploring the characteristics of nursing agencies in South Africa

    PubMed Central

    Olojede, Omolola I.; Rispel, Laetitia C.

    2015-01-01

    Background Nursing agencies are temporary employment service providers or labour brokers that supply nurses to health establishments. Objective This study was conducted to determine the characteristics of nursing agencies and their relationship with clients in the health sector. Methods During 2011, a cross-sectional national survey of 106 nursing agencies was conducted. After obtaining informed consent, telephone interviews were conducted with a representative of the selected nursing agency using a pretested structured questionnaire. Questions focused on the following: ownership, date of establishment, province of operation, distribution of clients across private and public health facilities; existence of a code of conduct; nature of the contractual relationship between nursing agencies and their clients, and numbers and cadres of nurses contracted. The survey data were analysed using STATA® 12. Results Fifty-two nursing agencies participated in the survey, representing a 49% response rate. The study found that 32 nursing agencies (62%) served private-sector clients only, which included private hospitals, homes for elderly people, patients in private homes, and private industry/company clinics, and only four (8%) of the agencies served the public sector only. Twenty-seven percent of nursing agencies provided services to homes for elderly individuals. Nursing agencies were more likely to have contracts with private-sector clients (84%) than with public-sector clients (16%) (p = 0.04). Although 98% of nursing agencies reported that they had a code of conduct, the proportion was higher for private-sector clients (73%) compared to public-sector clients (27%). In terms of quality checks and monitoring, 81% of agencies agreed with a statement that they checked the nursing council registration of nurses, 82% agreed with a statement that they requested certified copies of a nurse's qualifications. Only 21% indicated that they conducted reference checks of nurses with

  7. A comparative proteomics method for multiple samples based on a (18)O-reference strategy and a quantitation and identification-decoupled strategy.

    PubMed

    Wang, Hongbin; Zhang, Yongqian; Gui, Shuqi; Zhang, Yong; Lu, Fuping; Deng, Yulin

    2017-08-15

    Comparisons across large numbers of samples are frequently necessary in quantitative proteomics. Many quantitative methods used in proteomics are based on stable isotope labeling, but most of these are only useful for comparing two samples. For up to eight samples, the iTRAQ labeling technique can be used. For greater numbers of samples, the label-free method has been used, but this method was criticized for low reproducibility and accuracy. An ingenious strategy has been introduced, comparing each sample against a (18)O-labeled reference sample that was created by pooling equal amounts of all samples. However, it is necessary to use proportion-known protein mixtures to investigate and evaluate this new strategy. Another problem for comparative proteomics of multiple samples is the poor coincidence and reproducibility in protein identification results across samples. In present study, a method combining (18)O-reference strategy and a quantitation and identification-decoupled strategy was investigated with proportion-known protein mixtures. The results obviously demonstrated that the (18)O-reference strategy had greater accuracy and reliability than other previously used comparison methods based on transferring comparison or label-free strategies. By the decoupling strategy, the quantification data acquired by LC-MS and the identification data acquired by LC-MS/MS are matched and correlated to identify differential expressed proteins, according to retention time and accurate mass. This strategy made protein identification possible for all samples using a single pooled sample, and therefore gave a good reproducibility in protein identification across multiple samples, and allowed for optimizing peptide identification separately so as to identify more proteins. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Interlaboratory comparison of two AOAC liquid chromatographic fluorescence detection methods for paralytic shellfish toxin analysis through characterization of an oyster reference material.

    PubMed

    Turner, Andrew D; Lewis, Adam M; Rourke, Wade A; Higman, Wendy A

    2014-01-01

    An interlaboratory ring trial was designed and conducted by the Centre for Environment, Fisheries, and Aquaculture Science to investigate a range of issues affecting the analysis of a candidate Pacific oyster paralytic shellfish toxin reference material. A total of 21 laboratories participated in the study and supplied results using one or more of three instrumental methods, specifically precolumn oxidation (Pre-COX) LC with fluorescence detection (FLD; AOAC Official Method 2005.06), postcolumn oxidation (PCOX) LC-FLD (AOAC Official Method 2011.02), and hydrophilic interaction LC/MS/MS. Each participant analyzed nine replicate samples of the oyster tissue in three separate batches of three samples over a period of time longer than 1 week. Results were reported in a standardized format, reporting both individual toxin concentrations and total sample toxicity. Data were assessed to determine the equivalency of the two AOAC LC methods and the LC/MS/MS method as well as an assessment of intrabatch and interbatch repeatability and interlaboratory reproducibility of each method. Differences among the results reported using the three methods were shown to be statistically significant, although visual comparisons showed an overlap between results generated by the majority of tests, the exception being the Pre-COX quantitation of N-hydroxylated toxins in post ion-exchange fractions. Intralaboratory repeatability and interlaboratory reproducibility were acceptable for most of the results, with the exception of results generated from fractions. The results provided good evidence for the acceptable performance of the PCOX method for the quantitation of C toxins. Overall the study showed the usefulness of interlaboratory analysis for the characterization of paralytic shellfish poisoning matrix reference materials, highlighting some issues that may need to be addressed with further method assessment at individual participant laboratories.

  9. Dual energy X-ray absorptiometry body composition reference values of limbs and trunk from NHANES 1999–2004 with additional visualization methods

    PubMed Central

    Fan, Bo; Ng, Bennett K.; Shepherd, John A.

    2017-01-01

    Body Mass Index has traditionally been used as a measure of health, but Fat Mass Index (FMI) and Lean Mass Index (LMI) have been shown to be more predictive of mortality and health risk. Total body FMI and LMI reference curves have particularly been useful in quantifying sarcopenia and sarcopenic obesity. Research has shown regional composition has significant associations to health outcomes. We derived FMI and LMI reference curves of the regions of the body (leg, arm, and trunk) for 15,908 individuals in the 1999–2004 National Health and Nutrition Examination Survey data for each sex and ethnicity using the Lambda-Mu-Sigma (LMS) method and developed software to visualize this regional composition. These reference curves displayed differentiation between males and females during puberty and sharper limb LMI declines during late adulthood for males. For adults ages 30–50, females had 39%, 83%, and 47% larger arm, leg, and trunk FMI values than males, respectively. Males had 49%, 20%, and 15% higher regional LMI values than females for the arms, legs, and trunk respectively. The leg FMI and LMI of black females were 14% and 15% higher respectively than those of Hispanic and white females. White and Hispanic males had 37% higher trunk FMI values than black males. Hispanic females had 20% higher trunk FMI than white and black females. These data underscore the importance of accounting for sex and ethnicity in studies of regional composition. This study is the first to produce regional LMI and FMI reference tables and curves from the NHANES dataset. These reference curves provide a framework useful in studies and research involving sarcopenia, obesity, sarcopenic obesity, and other studies of compositional phenotypes. Further, the software tool we provide for visualizing regional composition will prove useful in monitoring progress in physical therapy, diets, or other attempts to attain healthier compositions. PMID:28346492

  10. Dual energy X-ray absorptiometry body composition reference values of limbs and trunk from NHANES 1999-2004 with additional visualization methods.

    PubMed

    Hinton, Benjamin J; Fan, Bo; Ng, Bennett K; Shepherd, John A

    2017-01-01

    Body Mass Index has traditionally been used as a measure of health, but Fat Mass Index (FMI) and Lean Mass Index (LMI) have been shown to be more predictive of mortality and health risk. Total body FMI and LMI reference curves have particularly been useful in quantifying sarcopenia and sarcopenic obesity. Research has shown regional composition has significant associations to health outcomes. We derived FMI and LMI reference curves of the regions of the body (leg, arm, and trunk) for 15,908 individuals in the 1999-2004 National Health and Nutrition Examination Survey data for each sex and ethnicity using the Lambda-Mu-Sigma (LMS) method and developed software to visualize this regional composition. These reference curves displayed differentiation between males and females during puberty and sharper limb LMI declines during late adulthood for males. For adults ages 30-50, females had 39%, 83%, and 47% larger arm, leg, and trunk FMI values than males, respectively. Males had 49%, 20%, and 15% higher regional LMI values than females for the arms, legs, and trunk respectively. The leg FMI and LMI of black females were 14% and 15% higher respectively than those of Hispanic and white females. White and Hispanic males had 37% higher trunk FMI values than black males. Hispanic females had 20% higher trunk FMI than white and black females. These data underscore the importance of accounting for sex and ethnicity in studies of regional composition. This study is the first to produce regional LMI and FMI reference tables and curves from the NHANES dataset. These reference curves provide a framework useful in studies and research involving sarcopenia, obesity, sarcopenic obesity, and other studies of compositional phenotypes. Further, the software tool we provide for visualizing regional composition will prove useful in monitoring progress in physical therapy, diets, or other attempts to attain healthier compositions.

  11. Evaluation of RNA extraction methods and identification of putative reference genes for real-time quantitative polymerase chain reaction expression studies on olive (Olea europaea L.) fruits.

    PubMed

    Nonis, Alberto; Vezzaro, Alice; Ruperti, Benedetto

    2012-07-11

    Genome wide transcriptomic surveys together with targeted molecular studies are uncovering an ever increasing number of differentially expressed genes in relation to agriculturally relevant processes in olive (Olea europaea L). These data need to be supported by quantitative approaches enabling the precise estimation of transcript abundance. qPCR being the most widely adopted technique for mRNA quantification, preliminary work needs to be done to set up robust methods for extraction of fully functional RNA and for the identification of the best reference genes to obtain reliable quantification of transcripts. In this work, we have assessed different methods for their suitability for RNA extraction from olive fruits and leaves and we have evaluated thirteen potential candidate reference genes on 21 RNA samples belonging to fruit developmental/ripening series and to leaves subjected to wounding. By using two different algorithms, GAPDH2 and PP2A1 were identified as the best reference genes for olive fruit development and ripening, and their effectiveness for normalization of expression of two ripening marker genes was demonstrated.

  12. Canadian listeriosis reference service.

    PubMed

    Pagotto, Franco; Ng, Lai-King; Clark, Clifford; Farber, Jeff

    2006-01-01

    Listeria monocytogenes, a psychrotrophic organism capable of growing at refrigeration temperatures, is of major concern in extended shelf life, refrigerated foods. Considering that as much as 80-90% of human listeriosis cases are linked to the ingestion of contaminated food, human cases are predominantly seen in high-risk individuals, including organ-transplant recipients, patients with AIDS and HIV-infected individuals, pregnant women, cancer patients, and the elderly. In 2001, the Canadian Listeriosis Reference Service (LRS) was created by the Bureau of Microbial Hazards (Health Canada) and the National Microbiology Laboratory (now part of the Public Health Agency of Canada). Major goals of the LRS include investigation of listeriosis cases and maintenance of a national collection of isolates. The LRS intends to create a comprehensive molecular epidemiological database of all isolates in Canada for use as a resource for outbreak investigations, research and other microbiological investigations. The PFGE profiles are being established and stored for clinical, food, environmental, and possibly animal strains of L. monocytogenes. The LRS pursues research activities for investigation and implementation of other molecular methods for characterizing L. monocytogenes isolates. Ribotyping, Multi-locus Sequence Typing (MLST), Variable Number of Tandem Repeats (VNTR), Multi-locus virulence sequence typing (MLVA), microarray- based technologies and sequence-based typing schemes, are being investigated on selected diversity sets. The LRS has also used PFGE typing for outbreak investigations. The molecular epidemiological data, timely coordination and exchange of information should help to reduce the incidence of listeriosis in Canada. In Canada, listeriosis is not a national notifiable disease, except for the province of Quebec, where it has been since 1999. The LRS, Canadian Public Health Laboratory Network, and federal epidemiologists are currently working on making human

  13. Measurements of Temperature Variations in the Atmosphere near the Tropopause with Reference to Airspeed Calibration by the Temperature Method

    NASA Technical Reports Server (NTRS)

    Lina, Lindsay J; Ricker, Harry H , Jr

    1952-01-01

    Measurements of temperature variations in the atmosphere near the tropopause over land in the vicinity of Langley Field, Va., are presented. This investigation was made for the purpose of obtaining information on the accuracy of the temperature method(NACA TN 2046) of airspeed calibration over the range of Mach number from 0.6 to .08. The temperature surveys and the description of a specially designed thermometer are also presented.

  14. Preparation of primary reference material of argon in oxygen by the gravimetric method for application to thermometry

    NASA Astrophysics Data System (ADS)

    Yang, Inseok; Bok Lee, Jin; Moon, Dong Min; Seog Kim, Jin

    2017-04-01

    Three mixtures of argon in oxygen with (1000, 350, 120) μmol mol-1 amount fractions of argon were prepared by the gravimetric method for application to thermometry. The mixtures are to be used to study the effects of argon impurity in oxygen on the temperature of the triple point of oxygen. From an uncertainty assessment compliant with the international standards, the relative uncertainty of the amount fraction of argon in the two-step dilution method used in this work ranged from 0.040% to 0.072%. The uncertainty was dominated by the uncertainties in weighing the mass of argon in the pre-mixture and weighing the mass of the pre-mixture in the final mixture. The internal consistency of the amount fraction of argon given by the gravimetric method was verified to be within 0.025% by measurements via gas chromatography with a thermal conductivity detector. The resultant uncertainty in the amount fraction of argon corresponds to less than 5 μK in the effect of argon impurity on the triple point of oxygen. Therefore, the mixtures have sufficient precision for the thermal study of the argon-in-oxygen mixtures.

  15. Environmental effects of dredging: Methods for the assessment of the genotoxic effects of environmental contaminants. Glossary and references. Technical notes

    SciTech Connect

    Honeycutt, M.E.; Jarvis, A.S.; McFarland, V.A.

    1995-07-01

    This technical note is the third in a series of three that outline and describe the principal methods that have been developed to test the potential of environmental contaminants to cause mutagenic, carcinogenic, and teratogenic effects. The first in this series (EEDP-04-24) describes methods used to discern genotoxic effects at the sub cellular level, while the second (EEDP-04-25) describes methods used to discern genotoxic effects at the cellular and organ/organism level. Recent literature citations for each topic referenced in this series of technical notes are provided in this technical note, in addition to a glossary of terms. The information in these technical notes is intended to provide Corps of Engineers personnel with a working knowledge of the terminology and conceptual basis of genotoxicity testing. To develop an improved understanding of the concepts of genotoxicity, readers are encouraged to review A Primer in Genotoxicity (Jarvis, Reilly, and Lutz 1993), presented in Volume D-93-3 of the Environmental Effects of Dredging information exchange bulletin.

  16. Combining canonical correlation analysis and infinite reference for frequency recognition of steady-state visual evoked potential recordings: a comparison with periodogram method.

    PubMed

    Tian, Yin; Li, Fali; Xu, Peng; Yuan, Zhen; Zhao, Dechun; Zhang, Haiyong

    2014-01-01

    Steady-state visual evoked potentials (SSVEP) are the visual system responses to a repetitive visual stimulus flickering with the constant frequency and of great importance in the study of brain activity using scalp electroencephalography (EEG) recordings. However, the reference influence for the investigation of SSVEP is generally not considered in previous work. In this study a new approach that combined the canonical correlation analysis with infinite reference (ICCA) was proposed to enhance the accuracy of frequency recognition of SSVEP recordings. Compared with the widely used periodogram method (PM), ICCA is able to achieve higher recognition accuracy when extracts frequency within a short span. Further, the recognition results suggested that ICCA is a very robust tool to study the brain computer interface (BCI) based on SSVEP.

  17. [Application and case analysis on the problem-based teaching of Jingluo Shuxue Xue (Science of Meridian and Acupoint) in reference to the team oriented learning method].

    PubMed

    Ma, Ruijie; Lin, Xianming

    2015-12-01

    The problem based teaching (PBT) has been the main approach to the training in the universities o the world. Combined with the team oriented learning method, PBT will become the method available to the education in medical universities. In the paper, based on the common questions in teaching Jingluo Shuxue Xue (Science of Meridian and Acupoint), the concepts and characters of PBT and the team oriented learning method were analyzed. The implementation steps of PBT were set up in reference to the team oriented learning method. By quoting the original text in Beiji Qianjin Yaofang (Essential recipes for emergent use worth a thousand gold), the case analysis on "the thirteen devil points" was established with PBT.

  18. Phenotypic and Phylogenetic Identification of Coliform Bacteria Obtained Using 12 Coliform Methods Approved by the U.S. Environmental Protection Agency.

    PubMed

    Zhang, Ya; Hong, Pei-Ying; LeChevallier, Mark W; Liu, Wen-Tso

    2015-09-01

    The current definition of coliform bacteria is method dependent, and when different culture-based methods are used, discrepancies in results can occur and affect the accuracy of identification of true coliforms. This study used an alternative approach to the identification of true coliforms by combining the phenotypic traits of the coliform isolates and the phylogenetic affiliation of 16S rRNA gene sequences with the use of lacZ and uidA genes. A collection of 1,404 isolates detected by 12 U.S. Environmental Protection Agency-approved coliform-testing methods were characterized based on their phylogenetic affiliations and responses to their original isolation media and lauryl tryptose broth, m-Endo, and MI agar media. Isolates were phylogenetically classified into 32 true-coliform, or targeted Enterobacteriaceae (TE), groups and 14 noncoliform, or nontargeted Enterobacteriaceae (NTE), groups. It was shown statistically that detecting true-positive (TP) events is more challenging than detecting true-negative (TN) events. Furthermore, most false-negative (FN) events were associated with four TE groups (i.e., Serratia group I and the Providencia, Proteus, and Morganella groups) and most false-positive (FP) events with two NTE groups, the Aeromonas and Plesiomonas groups. In Escherichia coli testing, 18 out of 145 E. coli isolates identified by enzymatic methods were validated as FN. The reasons behind the FP and FN reactions could be explained through analysis of the lacZ and uidA genes. Overall, combining the analyses of the 16S rRNA, lacZ, and uidA genes with the growth responses of TE and NTE on culture-based media is an effective way to evaluate the performance of coliform detection methods.

  19. Phenotypic and Phylogenetic Identification of Coliform Bacteria Obtained Using 12 Coliform Methods Approved by the U.S. Environmental Protection Agency

    PubMed Central

    Zhang, Ya; Hong, Pei-Ying; LeChevallier, Mark W.

    2015-01-01

    The current definition of coliform bacteria is method dependent, and when different culture-based methods are used, discrepancies in results can occur and affect the accuracy of identification of true coliforms. This study used an alternative approach to the identification of true coliforms by combining the phenotypic traits of the coliform isolates and the phylogenetic affiliation of 16S rRNA gene sequences with the use of lacZ and uidA genes. A collection of 1,404 isolates detected by 12 U.S. Environmental Protection Agency-approved coliform-testing methods were characterized based on their phylogenetic affiliations and responses to their original isolation media and lauryl tryptose broth, m-Endo, and MI agar media. Isolates were phylogenetically classified into 32 true-coliform, or targeted Enterobacteriaceae (TE), groups and 14 noncoliform, or nontargeted Enterobacteriaceae (NTE), groups. It was shown statistically that detecting true-positive (TP) events is more challenging than detecting true-negative (TN) events. Furthermore, most false-negative (FN) events were associated with four TE groups (i.e., Serratia group I and the Providencia, Proteus, and Morganella groups) and most false-positive (FP) events with two NTE groups, the Aeromonas and Plesiomonas groups. In Escherichia coli testing, 18 out of 145 E. coli isolates identified by enzymatic methods were validated as FN. The reasons behind the FP and FN reactions could be explained through analysis of the lacZ and uidA genes. Overall, combining the analyses of the 16S rRNA, lacZ, and uidA genes with the growth responses of TE and NTE on culture-based media is an effective way to evaluate the performance of coliform detection methods. PMID:26116679

  20. Poroelastic references

    SciTech Connect

    Morency, Christina

    2014-12-12

    This file contains a list of relevant references on the Biot theory (forward and inverse approaches), the double-porosity and dual-permeability theory, and seismic wave propagation in fracture porous media, in RIS format, to approach seismic monitoring in a complex fractured porous medium such as Brady?s Geothermal Field.