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Sample records for analytical methods validation

  1. OVERVIEW OF VALIDATION, BASIC CONCEPTS AND ANALYTICAL METHOD PROCESS VALIDATION

    OpenAIRE

    Indu Gurram* , M.V.S.Kavitha, M.V.Nagabhushnam, Brahmaiah Bonthagara, D.Nagarjuna Reddy

    2017-01-01

    Quality is the primordial intention to any industry and its products manufactured. Multiple views on obtaining such quality are the current interest in the pharmaceutical industry. Validation is the art of designing and practicing the designed steps alongside with the documentation. Validation and quality assurance will go hand in hand, ensuring the through quality for the products. When analytical method is utilized to generate results about the characteristics of drug related samples it is ...

  2. Validation of analytical methods based on accuracy profiles.

    Science.gov (United States)

    Feinberg, Max

    2007-07-27

    Validation is a very living field in analytical chemistry as illustrated by the numerous publications addressing this topic. But, there is some ambiguity in this concept and the abundant vocabulary often does not help the analytical chemist. This paper presents a new method based on the fitness-for-purpose approach of the validation. It consists in building a graphical decision-making tool, called the accuracy profile. Using measurements collected under reproducibility or intermediate precision condition, it allows computing an interval where a known proportion of future measurements will be located. When comparing this interval to an acceptability interval defined by the result end-user it is possible to simply decide whether a method is valid or not. The fundamentals of this method are presented starting from an accepted definition of validation. An example of application illustrates how validation can be experimentally organized and conclusion made.

  3. Development and Validation of Analytical Method for Losartan ...

    African Journals Online (AJOL)

    Development and Validation of Analytical Method for Losartan-Copper Complex Using UV-Vis Spectrophotometry. ... Tropical Journal of Pharmaceutical Research ... Purpose: To develop a new spectrophotometric method for the analysis of losartan potassium in pharmaceutical formulations by making its complex with ...

  4. Analytical methods validation of processes control in injectable antitumor agents

    International Nuclear Information System (INIS)

    Garcia Penna, Caridad Margarita; Cunill Semanat, Edel; Cartaya Morales, Mayra; Diaz de Arma, Anyisela; Curbelo Fonte, Yusleydis

    2010-01-01

    Alternative analytical methods were validated for the process control of 500 mg florouacil, 50 mg doxorrubicin and 50 mg methotrexate by spectrophotometry because of they are more simple and economic allowint to control the drugs quality in process analysis control. Calibration curves of fluorouracil, doxorrubicin and methotrexate were plotted in interval from 60 to 140%, where there were linear with correlation coefficients similar to 0.9998, 0.9999 and 0.9999, respectively; statistical text for intercept and slope were considered as non-significant. Recoveries of 99.97, 99.98 and 99.35% were achieved, respectively in study concentration interval and Cochran and t-Student tests were also non-significant. Methods were specific, linear, precises and exacts in interval of study concentrations

  5. Teaching Analytical Method Transfer through Developing and Validating Then Transferring Dissolution Testing Methods for Pharmaceuticals

    Science.gov (United States)

    Kimaru, Irene; Koether, Marina; Chichester, Kimberly; Eaton, Lafayette

    2017-01-01

    Analytical method transfer (AMT) and dissolution testing are important topics required in industry that should be taught in analytical chemistry courses. Undergraduate students in senior level analytical chemistry laboratory courses at Kennesaw State University (KSU) and St. John Fisher College (SJFC) participated in development, validation, and…

  6. Oxcarbazepine: validation and application of an analytical method

    Directory of Open Access Journals (Sweden)

    Paula Cristina Rezende Enéas

    2010-06-01

    Full Text Available Oxcarbazepine (OXC is an important anticonvulsant and mood stabilizing drug. A pharmacopoeial monograph for OXC is not yet available and therefore the development and validation of a new analytical method for quantification of this drug is essential. In the present study, a UV spectrophotometric method for the determination of OXC was developed. The various parameters, such as linearity, precision, accuracy and specificity, were studied according to International Conference on Harmonization Guidelines. Batches of 150 mg OXC capsules were prepared and analyzed using the validated UV method. The formulations were also evaluated for parameters including drug-excipient compatibility, flowability, uniformity of weight, disintegration time, assay, uniformity of content and the amount of drug dissolved during the first hour.Oxcarbazepina (OXC é um fármaco anticonvulsivante e estabilizante do humor. O desenvolvimento e validação de método analítico para quantificação da OXC são de fundamental importância devido à ausência de monografias farmacopéicas oficiais para esse fármaco. Nesse trabalho, um método espectrofotométrico UV para determinação da OXC foi desenvolvido. O método proposto foi validado seguindo os parâmetros de linearidade, precisão, exatidão e especificidade de acordo com as normas da Conferência Internacional de Harmonização. Cápsulas de OXC 150 mg foram preparadas e analisadas utilizando-se o método analítico validado. As formulações foram avaliadas com relação à compatibilidade fármaco-excipientes, fluidez, determinação de peso, tempo de desintegração, doseamento, uniformidade de conteúdo e quantidade do fármaco dissolvido após 60 minutos.

  7. Analytical models approximating individual processes: a validation method.

    Science.gov (United States)

    Favier, C; Degallier, N; Menkès, C E

    2010-12-01

    Upscaling population models from fine to coarse resolutions, in space, time and/or level of description, allows the derivation of fast and tractable models based on a thorough knowledge of individual processes. The validity of such approximations is generally tested only on a limited range of parameter sets. A more general validation test, over a range of parameters, is proposed; this would estimate the error induced by the approximation, using the original model's stochastic variability as a reference. This method is illustrated by three examples taken from the field of epidemics transmitted by vectors that bite in a temporally cyclical pattern, that illustrate the use of the method: to estimate if an approximation over- or under-fits the original model; to invalidate an approximation; to rank possible approximations for their qualities. As a result, the application of the validation method to this field emphasizes the need to account for the vectors' biology in epidemic prediction models and to validate these against finer scale models. Copyright © 2010 Elsevier Inc. All rights reserved.

  8. Introduction to Validation of Analytical Methods: Potentiometric Determination of CO[subscript 2

    Science.gov (United States)

    Hipólito-Nájera, A. Ricardo; Moya-Hernandez, M. Rosario; Gomez-Balderas, Rodolfo; Rojas-Hernandez, Alberto; Romero-Romo, Mario

    2017-01-01

    Validation of analytical methods is a fundamental subject for chemical analysts working in chemical industries. These methods are also relevant for pharmaceutical enterprises, biotechnology firms, analytical service laboratories, government departments, and regulatory agencies. Therefore, for undergraduate students enrolled in majors in the field…

  9. Development and Validation of Analytical Method for Losartan ...

    African Journals Online (AJOL)

    HP

    Purpose: To develop a new spectrophotometric method for the analysis of losartan potassium in pharmaceutical formulations by making its complex with copper. Method: A coloured complex based on UV/Vis spectroscopic method was developed for the determination of losartan potassium concentration in pharmaceutical ...

  10. Validation of methods performance for routine biochemistry analytes at Cobas 6000 analyzer series module c501.

    Science.gov (United States)

    Supak Smolcic, Vesna; Bilic-Zulle, Lidija; Fisic, Elizabeta

    2011-01-01

    Cobas 6000 (Roche, Germany) is biochemistry analyzer for spectrophotometric, immunoturbidimetric and ion-selective determination of biochemical analytes. Hereby we present analytical validation with emphasis on method performance judgment for routine operation. Validation was made for 30 analytes (metabolites, enzymes, trace elements, specific proteins and electrolytes). Research included determination of within-run (N = 20) and between-run imprecision (N = 30), inaccuracy (N = 30) and method comparison with routine analyzer (Beckman Coulter AU640) (N = 50). For validation of complete analytical process we calculated total error (TE). Results were judged according to quality specification criteria given by European Working Group. Within-run imprecision CVs were all below 5% except for cholesterol, triglycerides, IgA and IgM. Between-run CVs for all analytes were below 10%. Analytes that did not meet the required specifications for imprecision were: total protein, albumin, calcium, sodium, chloride, immunoglobulins and HDL cholesterol. Analytes that did not fulfill requirements for inaccuracy were: total protein, calcium, sodium and chloride. Analytes that deviated from quality specifications for total error were: total protein, albumin, calcium, sodium, chloride and IgM. Passing-Bablok regression analysis provided linear equation and 95% confidence interval for intercept and slope. Complete accordance with routine analyzer Beckman Coulter AU640 showed small number of analytes. Other analytes showed small proportional and/or small constant difference and therefore need to be adjusted for routine operation. Regarding low CV values, tested analyzer has satisfactory accuracy and precision and is extremely stable. Except for analytes that are coherent on both analyzers, some analytes require adjustments of slope and intercept for complete accordance.

  11. Analytical Quality by Design Approach to Test Method Development and Validation in Drug Substance Manufacturing

    Directory of Open Access Journals (Sweden)

    N. V. V. S. S. Raman

    2015-01-01

    Full Text Available Pharmaceutical industry has been emerging rapidly for the last decade by focusing on product Quality, Safety, and Efficacy. Pharmaceutical firms increased the number of product development by using scientific tools such as QbD (Quality by Design and PAT (Process Analytical Technology. ICH guidelines Q8 to Q11 have discussed QbD implementation in API synthetic process and formulation development. ICH Q11 guidelines clearly discussed QbD approach for API synthesis with examples. Generic companies are implementing QbD approach in formulation development and even it is mandatory for USFDA perspective. As of now there is no specific requirements for AQbD (Analytical Quality by Design and PAT in analytical development from all regulatory agencies. In this review, authors have discussed the implementation of QbD and AQbD simultaneously for API synthetic process and analytical methods development. AQbD key tools are identification of ATP (Analytical Target Profile, CQA (Critical Quality Attributes with risk assessment, Method Optimization and Development with DoE, MODR (method operable design region, Control Strategy, AQbD Method Validation, and Continuous Method Monitoring (CMM. Simultaneous implementation of QbD activities in synthetic and analytical development will provide the highest quality product by minimizing the risks and even it is very good input for PAT approach.

  12. Validation of the analytical method for sodium dichloroisocyanurate aimed at drinking water disinfection

    International Nuclear Information System (INIS)

    Martinez Alvarez, Luis Octavio; Alejo Cisneros, Pedro; Garcia Pereira, Reynaldo; Campos Valdez, Doraily

    2014-01-01

    Cuba has developed the first effervescent 3.5 mg sodium dichloroisocyanurate tablets as a non-therapeutic active principle. This ingredient releases certain amount of chlorine when dissolved into a litre of water and it can cause adequate disinfection of drinking water ready to be taken after 30 min. Developing and validating an analytical iodometric method applicable to the quality control of effervescent 3.5 mg sodium dichloroisocyanurate tablets

  13. Moxidectin residues in lamb tissues: Development and validation of analytical method by UHPLC-MS/MS.

    Science.gov (United States)

    Del Bianchi A Cruz, Michelle; Fernandes, Maria A M; de C Braga, Patricia A; Monteiro, Alda L G; Daniel, Daniela; Reyes, Felix G R

    2018-01-01

    The development and validation of a throughput method for the quantitation of moxidectin residues in lamb target tissues (muscle, kidney, liver and fat) was conducted using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). To achieve higher recovery of the analyte from the matrices, a modified QuEChERS method was used for sample preparation. The chromatographic separation was achieved using a Zorbax Eclipse Plus C18 RRHD column with a mobile phase comprising 5mM ammonium formate solution +0.1% formic acid (A) and acetonitrile +0.1% formic acid (B) in a linear gradient program. Method validation was performed based on the Commission Decision 2002/657/EC and VICH GL49. To quantify the analyte, matrix-matched analytical curves were constructed with spiked blank tissues, with a limit of quantitation of 5ngg -1 and limit of detection of 1.5ngg -1 for all matrices. The linearity, decision limit, detection capability accuracy, and inter- and intra-day repeatability of the method are reported. The method was successfully applied to incurred lamb tissue samples (muscle, liver, kidney and fat) in a concentration range from 5 to 200μgkg -1 , which demonstrated its suitability for monitoring moxidectin residues in lamb tissues in health surveillance programs, as well as for pharmacokinetics and residue depletion studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Validation of an analytical method for quality control and stability study of 10 % Phenylephrine eyedrops

    International Nuclear Information System (INIS)

    Monteagudo Licea, Raiza; Garcia Penna, Caridad Margarita; Botet Garcia, Martha

    2010-01-01

    Phenylephrine is used like mydiatric in eye examinations and other ophthalmic procedures. It is used as vasoconstrictor with local anesthetic agents. In present paper a high resolution liquid chromatography analytical method was validated to quality control and stability studies of 10 % Phenylephrine (eyedrops). Method was based in separation of active principle through a Lichrosorb RO-18 (5 μm) (250 x 4 mm) chromatography column with UV detection at 280 nm using a mobile phase composed by a non-gasified mixture of methanol distilled water (1:1) with 1.1 g of 1-sodium octane-sulphonate by liter adjusted to pH 3,0 with phosphoric acid at a flow speed of 1.0 mL/min. Analytical method was linear, accuracy, specific and exact in the interval of study concentrations

  15. Validation of analytical method for quality control of B12 Vitamin-10 000 injection

    International Nuclear Information System (INIS)

    Botet Garcia, Martha; Garcia Penna, Caridad Margarita; Troche Concepcion, Yenilen; Cannizares Arencibia, Yanara; Moreno Correoso, Barbara

    2009-01-01

    Analytical method reported by USA Pharmacopeia was validated for quality control of injectable B 1 2 Vitamin (10 000 U) by UV spectrophotometry because this is a simpler and low-cost method allowing quality control of finished product. Calibration curve was graphed at 60 to 140% interval, where it was linear with a correlation coefficient similar to 0, 9999; statistical test for interception and slope was considered non-significant. There was a recovery of 99.7 % in study concentrations interval where the Cochran (G) and Student(t) test were not significant too. Variation coefficient in repetition study was similar to 0.59 % for the 6 assayed replies, whereas in intermediate precision analysis, the Fisher and Student tests were not significant. Analytical method was linear, precise, specific and exact in study concentrations interval

  16. Analytical method validation for quality control and the study of the 50 mg Propylthiouracil stability

    International Nuclear Information System (INIS)

    Valdes Bendoyro, Maria Olga; Garcia Penna, Caridad Margarita; Fernandez, Juan Lugones; Garcia Borges, Lisandra; Martinez Espinosa, Vivian

    2010-01-01

    A high-performance liquid chromatography analytical method was developed and validated for the quality control and stability studies of 50 mg Propylthiouracil tablets. Method is based in active principle separation through a 100 RP-18 RP-18 (5 μm) (250 x 4 mm) Lichrospher chromatography with UV detection to 272 nm, using a mobile phase composed by a ungaseous mixture of a 0.025 M buffer solution-monobasic potassium phosphate to pH= 4,6 ad acetonitrile in a 80:20 ratio with a flux speed of 0,5 mL/min. Analytical method was linear, precise, specific and exact in the study concentrations interval

  17. Formulation and Development of a Validated UV-Spectrophotometric Analytical Method of Rutin Tablet

    Directory of Open Access Journals (Sweden)

    Murad N. Abualhasan

    2017-01-01

    Full Text Available Rutin is available in some foods, fruits, and vegetables. It has various beneficial medical effects making it useful in the treatment of various diseases. Rutin is available in different oral dosage forms such as tablets or capsules, widely available in the market. Rutin and many herbal medicines lack quality control due to unavailability of analytical methods. In this study, we formulated rutin tablet and studied its stability using a simple developed analytical method. The dissolution profile of our formulated tablet was also inspected. The results showed that our developed method was linear (R2=0.999, precise (% RSD = 0.026, and accurate (% recovery = 98.55–103.34. The formulated rutin tablet was stable under accelerated conditions as well as room temperature for 150 days (% assay > 91.69. The dissolution profile over 45 minutes of our formulated tablet showed a better dissolution (26.5% compared with the internationally marketed Rutin® tablet (18.5%. This study can serve as a guideline to companies that manufacture herbal products to improve their formulated herbs and apply validated analytical methods to check the quality of their product.

  18. Validation of analytical methods for the stability studies of naproxen suppositories for infant and adult use

    International Nuclear Information System (INIS)

    Rodriguez Hernandez, Yaslenis; Suarez Perez, Yania; Garcia Pulpeiro, Oscar

    2011-01-01

    Analytical and validating studies were performed in this paper, with a view to using them in the stability studies of the future formulations of naproxen suppositories for children and adults. The most influential factors in the naproxen stability were determined, that is, the major degradation occurred in acid medium, oxidative medium and by light action. One high-performance liquid chromatography-based method was evaluated, which proved to be adequate to quantify naproxen in suppositories and was selective against degradation products. The quantification limit was 3,480 μg, so it was valid for these studies. Additionally, the parameters specificity for stability, detection and quantification limits were evaluated for the direct semi-aqueous acid-base method, which was formerly validated for the quality control and showed satisfactory results. Nevertheless, the volumetric methods were not regarded as stability indicators; therefore, this method will be used along with the chromatographic methods of choice, that is, thin-layer chromatography and highperformance liquid chromatography, to determine the degradation products

  19. Development and validation of HPLC analytical method for quantitative determination of metronidazole in human plasma

    International Nuclear Information System (INIS)

    Safdar, K.A.; Shyum, S.B.; Usman, S.

    2016-01-01

    The objective of the present study was to develop a simple, rapid and sensitive reversed-phase high performance liquid chromatographic (RP-HPLC) analytical method with UV detection system for the quantitative determination of metronidazole in human plasma. The chromatographic separation was performed by using C18 RP column (250mm X 4.6mm, 5 meu m) as stationary phase and 0.01M potassium dihydrogen phosphate buffered at pH 3.0 and acetonitrile (83:17, v/v) as mobile phase at flow rate of 1.0 ml/min. The UV detection was carried out at 320nm. The method was validated as per the US FDA guideline for bioanalytical method validation and was found to be selective without interferences from mobile phase components, impurities and biological matrix. The method found to be linear over the concentration range of 0.2812 meu g/ml to 18.0 meu g/ml (r2 = 0.9987) with adequate level of accuracy and precision. The samples were found to be stable under various recommended laboratory and storage conditions. Therefore, the method can be used with adequate level of confidence and assurance for bioavailability, bioequivalence and other pharmacokinetic studies of metronidazole in human. (author)

  20. Development and Validation Dissolution Analytical Method of Nimesulide beta-Cyclodextrin 400 mg Tablet

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Carvalho Pereira

    2016-10-01

    Full Text Available The nimesulide (N-(4-nitro-2-phenoxyphenylmethanesulfonamide belongs to the class of non-steroidal anti-inflammatory drugs (NSAIDs and category II of the biopharmaceutical classification, The complexation of nimesulide with b-cyclodextrin is a pharmacological strategy to increase the solubility of the drug The objective of this study was to develop and validate an analytical methodology for dissolving the nimesulide beta-cyclodextrin 400 mg tablet and meets the guidelines of ANVISA for drug registration purposes. Once developed, the dissolution methodology was validated according to the RE of parameters no.  899/2003. In the development of the method it was noted that the duration of the dissolution test was 60 minutes, the volume and the most suitable dissolution medium was 900 mL of aqueous solution of sodium lauryl sulfate 1% (w/ v. It was also noted that rotation of 100 rpm and the paddle apparatus was the most appropriate to evaluate the dissolution of the drug. Spectrophotometric methodology was used to quantify the percentage of dissolved drug. The wavelength was 390 nm using the quantification. The validation of the methodology, system suitability parameters, specificity/selectivity, linearity, precision, accuracy and robustness were satisfactory and proved that the developed dissolution methodology was duly executed. DOI: http://dx.doi.org/10.17807/orbital.v8i5.827

  1. Characterization and validation of sampling and analytical methods for mycotoxins in workplace air.

    Science.gov (United States)

    Jargot, Danièle; Melin, Sandrine

    2013-03-01

    Mycotoxins are produced by certain plant or foodstuff moulds under growing, transport or storage conditions. They are toxic for humans and animals, some are carcinogenic. Methods to monitor occupational exposure to seven of the most frequently occurring airborne mycotoxins have been characterized and validated. Experimental aerosols have been generated from naturally contaminated particles for sampler evaluation. Air samples were collected on foam pads, using the CIP 10 personal aerosol sampler with its inhalable health-related aerosol fraction selector. The samples were subsequently solvent extracted from the sampling media, cleaned using immunoaffinity (IA) columns and analyzed by liquid chromatography with fluorescence detection. Ochratoxin A (OTA) or fumonisin and aflatoxin derivatives were detected and quantified. The quantification limits were 0.015 ng m(-3) OTA, 1 ng m(-3) fumonisins or 0.5 pg m(-3) aflatoxins, with a minimum dust concentration level of 1 mg m(-3) and a 4800 L air volume sampling. The methods were successfully applied to field measurements, which confirmed that workers could be exposed when handling contaminated materials. It was observed that airborne particles may be more contaminated than the bulk material itself. The validated methods have measuring ranges fully adapted to the concentrations found in the workplace. Their performance meets the general requirements laid down for chemical agent measurement procedures, with an expanded uncertainty less than 50% for most mycotoxins. The analytical uncertainty, comprised between 14 and 24%, was quite satisfactory given the low mycotoxin amounts, when compared to the food benchmarks. The methods are now user-friendly enough to be adopted for personal workplace sampling. They will later allow for mycotoxin occupational risk assessment, as only very few quantitative data have been available till now.

  2. Validation of analytical method to calculate the concentration of conjugated monoclonal antibody

    International Nuclear Information System (INIS)

    Alcarde, Lais F.; Massicano, Adriana V.F.; Oliveira, Ricardo S.; Araujo, Elaine B. de

    2013-01-01

    The objective of this study was to develop a quantitative analytical method using high performance liquid chromatography (HPLC) to determine the antibody concentration in conjunction with bifunctional chelator. Assays were performed using a high performance liquid chromatograph, and the following conditions were used: flow rate of 1 mL / min, 15 min run time, 0.2 M sodium phosphate buffer pH 7.0 as the mobile phase and column of molecular exclusion BioSep SEC S-3000 (300 x 7.8 mm, 5 μM - Phenomenex). The calibration curve was obtained with AcM diluted in 0.2 M sodium phosphate buffer pH 7.0 by serial dilution, yielding the concentrations: 400 μg/mL, 200 μg/mL, 100 μg/mL, 50 μg/mL, 25 μg/mL and 12.5 μg/mL. From the calibration curve calculated the equation of the line and with it the concentration of the immunoconjugate. To ensure the validity of the method accuracy and precision studies were conducted. The accuracy test consisted in the evaluation of 3 samples of known concentration, being this test performed with low concentrations (50 μg/mL), medium (100 μg/mL) and high (200 μg/mL). The precision test consisted of 3 consecutive measurements of one sample of known concentration, subject to the conditions set forth above for the other tests. The correlation coefficient of the standard curve was greater than 97%, the accuracy was satisfactory at low concentrations as well as accuracy. The method was validated by showing it for the accurate and precise determination of the concentration of the immunoconjugate. Furthermore, this assay was found to be extremely important, because using the correct mass of the protein, the radiochemical purity of the radioimmunoconjugate was above 95% in all studies

  3. Occurrence of erythromycin residues in sheep milk. Validation of an analytical method.

    Science.gov (United States)

    García-Mayor, M A; Paniagua-González, G; Soledad-Rodríguez, B; Garcinuño-Martínez, R M; Fernández-Hernando, P; Durand-Alegría, J S

    2015-04-01

    The paper describes a new and selective analytical sample treatment for quantitative extraction and preconcentration of erythromycin in presence of other macrolide antibiotics in sheep milk samples. The methodology is based on the use of a molecular imprinted polymer (MIP) employed as solid phase extraction sorbent (MISPE). The synthesized material by bulk polymerization using erythromycin (ERY) as template was evaluated as solid phase extraction sorbent, in a novel sample treatment technique that can be coupled to high-performance liquid chromatography with diode-array detector (HPLC-DAD). MIP selectivity was studied for other macrolide antibiotics with similar structures, such as tylosin (TYL), spiramycin (SPI), josamycin (JOS), roxithromycin (ROX) and ivermectin (IVER) getting recoveries for these interferents lower than 35%, for all cases except for ROX, which recoveries were around 85%. The variables affecting the molecularly imprinted solid-phase extraction (MISPE) procedure were optimized to select the best conditions of selectivity and sensitivity to determine ERY at concentration levels established by EU legislation in sheep milk. Under the selected experimental conditions, quantification limit was 24.1 µg kg(-1). Recoveries were higher than 98%, with RSDs between 0.7% and 2%. The proposed MISPE-HPLC method was validated and successfully applied to ERY analysis in sheep milk samples. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Development and validation of analytical method for Naftopidil in human plasma by LC–MS/MS

    Directory of Open Access Journals (Sweden)

    Pritam S. Jain

    2015-09-01

    Full Text Available A highly sensitive and simple high-performance liquid chromatographic–tandem mass spectrometric (LC–MS-MS assay is developed and validated for the quantification of Naftopidil in human plasma. Naftopidil is extracted from human plasma by methyl tertiary butyl ether and analyzed using a reversed-phase gradient elution on a discovery C 18 5 μ (50 × 4.6 column. A methanol: 2 mM ammonium formate (90:10 as mobile phase, is used and detection was performed by MS using electrospray ionization in positive mode. Propranolol is used as the internal standard. The lower limits of quantification are 0.495 ng/mL. The calibration curves are linear over the concentration range of 0.495–200.577 ng/mL of plasma for each analyte. This novel LC–MS-MS method shows satisfactory accuracy and precision and is sufficiently sensitive for the performance of pharmacokinetic studies in humans.

  5. VALIDATION OF ANALYTICAL METHODS AND INSTRUMENTATION FOR BERYLLIUM MEASUREMENT: REVIEW AND SUMMARY OF AVAILABLE GUIDES, PROCEDURES, AND PROTOCOLS

    Energy Technology Data Exchange (ETDEWEB)

    Ekechukwu, A.

    2008-12-17

    This document proposes to provide a listing of available sources which can be used to validate analytical methods and/or instrumentation for beryllium determination. A literature review was conducted of available standard methods and publications used for method validation and/or quality control. A comprehensive listing of the articles, papers, and books reviewed is given in Appendix 1. Available validation documents and guides are listed in the appendix; each has a brief description of application and use. In the referenced sources, there are varying approaches to validation and varying descriptions of validation at different stages in method development. This discussion focuses on validation and verification of fully developed methods and instrumentation that have been offered up for use or approval by other laboratories or official consensus bodies such as ASTM International, the International Standards Organization (ISO) and the Association of Official Analytical Chemists (AOAC). This review was conducted as part of a collaborative effort to investigate and improve the state of validation for measuring beryllium in the workplace and the environment. Documents and publications from the United States and Europe are included. Unless otherwise specified, all documents were published in English.

  6. VALIDATION OF ANALYTICAL METHODS AND INSTRUMENTATION FOR BERYLLIUM MEASUREMENT: REVIEW AND SUMMARY OF AVAILABLE GUIDES, PROCEDURES, AND PROTOCOLS

    Energy Technology Data Exchange (ETDEWEB)

    Ekechukwu, A

    2009-05-27

    Method validation is the process of evaluating whether an analytical method is acceptable for its intended purpose. For pharmaceutical methods, guidelines from the United States Pharmacopeia (USP), International Conference on Harmonisation (ICH), and the United States Food and Drug Administration (USFDA) provide a framework for performing such valications. In general, methods for regulatory compliance must include studies on specificity, linearity, accuracy, precision, range, detection limit, quantitation limit, and robustness. Elements of these guidelines are readily adapted to the issue of validation for beryllium sampling and analysis. This document provides a listing of available sources which can be used to validate analytical methods and/or instrumentation for beryllium determination. A literature review was conducted of available standard methods and publications used for method validation and/or quality control. A comprehensive listing of the articles, papers and books reviewed is given in the Appendix. Available validation documents and guides are listed therein; each has a brief description of application and use. In the referenced sources, there are varying approches to validation and varying descriptions of the valication process at different stages in method development. This discussion focuses on valication and verification of fully developed methods and instrumentation that have been offered up for use or approval by other laboratories or official consensus bodies such as ASTM International, the International Standards Organization (ISO) and the Association of Official Analytical Chemists (AOAC). This review was conducted as part of a collaborative effort to investigate and improve the state of validation for measuring beryllium in the workplace and the environment. Documents and publications from the United States and Europe are included. Unless otherwise specified, all referenced documents were published in English.

  7. Development and validation of the analytical method by high performance liquid chromatography (HPLC for Lamotrigine raw material Development and validation of the analytical method by high performance liquid chromatography (HPLC for Lamotrigine raw material

    Directory of Open Access Journals (Sweden)

    Hisao Nishijo

    2011-09-01

    Full Text Available Currently when all roads lead to the pursuit of total quality in production of drugs, it is essential to fully understand each phase of a production process. In this case, validation is the appropriate tool to ensure reliability of a production process involving new equipment and the analytical methodology, either in the pharmaceutical, food, computer, microelectronics area or any other area where the quality of the manufactured product is one of the main reasons for the existence of a given company. This study aimed to analyze the main aspects of the validation of analytical methods for Lamotrigine, new drug for bipolar disorder with wide use today. In conclusion, the proposed analytical method for determination of the lamotrigine content in raw materials is adequate, effective and capable of reproducing reliable results during analysis. This method is fast (running time of 10 minutes, selective, accurate, precise and robust for the determination of the drug, with no observed interfering substances in the optimum wavelength. It could be concluded that this may be a routine method for quality control laboratories to certify the quality of Lamotrigine.Currently when all roads lead to the pursuit of total quality in production of drugs, it is essential to fully understand each phase of a production process. In this case, validation is the appropriate tool to ensure reliability of a production process involving new equipment and the analytical methodology, either in the pharmaceutical, food, computer, microelectronics area or any other area where the quality of the manufactured product is one of the main reasons for the existence of a given company. This study aimed to analyze the main aspects of the validation of analytical methods for Lamotrigine, new drug for bipolar disorder with wide use today. In conclusion, the proposed analytical method for determination of the lamotrigine content in raw materials is adequate, effective and capable of

  8. [Validation Study for Analytical Method of Diarrhetic Shellfish Poisons in 9 Kinds of Shellfish].

    Science.gov (United States)

    Yamaguchi, Mizuka; Yamaguchi, Takahiro; Kakimoto, Kensaku; Nagayoshi, Haruna; Okihashi, Masahiro; Kajimura, Keiji

    2016-01-01

    A method was developed for the simultaneous determination of okadaic acid, dinophysistoxin-1 and dinophysistoxin-2 in shellfish using ultra performance liquid chromatography with tandem mass spectrometry. Shellfish poisons in spiked samples were extracted with methanol and 90% methanol, and were hydrolyzed with 2.5 mol/L sodium hydroxide solution. Purification was done on an HLB solid-phase extraction column. This method was validated in accordance with the notification of Ministry of Health, Labour and Welfare of Japan. As a result of the validation study in nine kinds of shellfish, the trueness, repeatability and within-laboratory reproducibility were 79-101%, less than 12 and 16%, respectively. The trueness and precision met the target values of notification.

  9. Validation of an analytical method for the determination of the sodium content in foods

    International Nuclear Information System (INIS)

    Valverde Montero, Ericka; Silva Trejos, Paulina

    2012-01-01

    The analytical methodology for quantitative determination of sodium in foods by flame atomic absorption spectrometry was validated. The samples of 0,5 g was realized by microwave oven with 5,0 mL of nitric acid (HNO 3 ) to 65% by mass. The linearity range has been from 0,043 mg/L to 0,70 mg/L with a correlation coefficient equal to 0,998. The detection and quantification limits have reported 0,025 mg/L and 0,043 mg/L, respectively; with 0,805 Lmg -1 of calibration sensitivity and 44 Lmg -1 of analytical sensitivity. The precision was evaluated in terms of repeatability and have obtained a value equal to 2,9% RDS r . The trueness was determined using three NIST ® , certified standards SRM 1846 Infant Formula with a reported value for sodium of (2310 ± 130) mg/kg, SRM 8414 Bovine Muscle Powder with a reported value for sodium of (0,210 ± 0,008)% and SRM 8415 Whole Egg Powder with a reported value for sodium of (0,377 ± 0,034)% by mass. The bias have obtained an average between(-0,010 to 0,009) mg/L. From the list of foods that were selected for the study, for example, whole milk powder, white wheat bread, fresh cheese and mozzarella cheese have submitted highest content in sodium concentrations, ranging from (106 to 452) mg Na /100g. (author) [es

  10. Impurities in biogas - validation of analytical methods for siloxanes; Foeroreningar i biogas - validering av analysmetodik foer siloxaner

    Energy Technology Data Exchange (ETDEWEB)

    Arrhenius, Karine; Magnusson, Bertil; Sahlin, Eskil [SP Technical Research Institute of Sweden, Boraas (Sweden)

    2011-11-15

    Biogas produced from digester or landfill contains impurities which can be harmful for component that will be in contact with the biogas during its utilization. Among these, the siloxanes are often mentioned. During combustion, siloxanes are converted to silicon dioxide which accumulates on the heated surfaces in combustion equipment. Silicon dioxide is a solid compound and will remain in the engine and cause damages. Consequently, it is necessary to develop methods for the accurate determination of these compounds in biogases. In the first part of this report, a method for analysis of siloxanes in biogases was validated. The sampling was performed directly at the plant by drawing a small volume of biogas onto an adsorbent tube under a short period of time. These tubes were subsequently sent to the laboratory for analysis. The purpose of method validation is to demonstrate that the established method is fit for the purpose. This means that the method, as used by the laboratory generating the data, will provide data that meets a set of criteria concerning precision and accuracy. At the end, the uncertainty of the method was calculated. In the second part of this report, the validated method was applied to real samples collected in waste water treatment plants, co-digestion plants and plants digesting other wastes (agriculture waste). Results are presented at the end of this report. As expected, the biogases from waste water treatment plants contained largely higher concentrations of siloxanes than biogases from co-digestion plants and plants digesting agriculture wastes. The concentration of siloxanes in upgraded biogas regardless of which feedstock was digested and which upgrading technique was used was low.

  11. ANALYTICAL METHOD DEVELOPMENT AND VALIDATION FOR SIMULTANEOUS ESTIMATION OF SIMVASTATIN AND SITAGLIPTIN

    OpenAIRE

    Yaddanapudi Mrudula Devi; R. Karthikeyan; Punttaguntla Sreenivasa Babu

    2013-01-01

    A simple, specific, accurate, rapid, inexpensive isocratic Reversed Phase-High Performance Liquid Chromatography (RP-HPLC) method was developed and validated for the quantitative determination of Simvastatin and Sitagliptin pharmaceutical tablet dosage forms. RP-HPLC method was developed by using Inertsil ODS-3 C 18 (75 mm*4.6 mm) 5 microns Short column, Shimadzu LC-20AT Prominence Liquid Chromatograph. The mobile phase composed of 0.05 M Ammonium acetate: CAN 60:40. The flow rate was set to ...

  12. Validation of the Analytical Method for the Determination of Flavonoids in Broccoli

    Directory of Open Access Journals (Sweden)

    Tuszyńska Magdalena

    2014-09-01

    Full Text Available A simple, accurate and selective HPLC method was developed and validated for determination of quercetin and kaempferol, which are the main flavonols in broccoli. The separation was achieved on a reversed-phase C18 column using a mobile phase composed of methanol/water (60/40 and phosphoric acid 0.2% at a flow rate of 1.0 ml min-1. The detection was carried out on a DAD detector at 370 nm. This method was validated according to the requirements for new methods, which include selectivity, linearity, precision, accuracy, limit of detection and limit of quantitation. The current method demonstrates good linearity, with R2 > 0.99. The recovery is within 98.07-102.15% and 97.92-101.83% for quercetin and kaempferol, respectively. The method is selective, in that quercetin and kaempferol are well separated from other compounds of broccoli with good resolution. The low limit of detection and limit of quantitation of quercetin and kaempferol enable the detection and quantitation of these flavonoids in broccoli at low con–centrations.

  13. Validation of the analytical methods in the LWR code BOXER for gadolinium-loaded fuel pins

    International Nuclear Information System (INIS)

    Paratte, J.M.; Arkuszewski, J.J.; Kamboj, B.K.; Kallfelz, J.M.; Abdel-Khalik, S.I.

    1990-01-01

    Due to the very high absorption occurring in gadolinium-loaded fuel pins, calculations of lattices with such pins present are a demanding test of the analysis methods in light water reactor (LWR) cell and assembly codes. Considerable effort has, therefore, been devoted to the validation of code methods for gadolinia fuel. The goal of the work reported in this paper is to check the analysis methods in the LWR cell/assembly code BOXER and its associated cross-section processing code ETOBOX, by comparison of BOXER results with those from a very accurate Monte Carlo calculation for a gadolinium benchmark problem. Initial results of such a comparison have been previously reported. However, the Monte Carlo calculations, done with the MCNP code, were performed at Los Alamos National Laboratory using ENDF/B-V data, while the BOXER calculations were performed at the Paul Scherrer Institute using JEF-1 nuclear data. This difference in the basic nuclear data used for the two calculations, caused by the restricted nature of these evaluated data files, led to associated uncertainties in a comparison of the results for methods validation. In the joint investigations at the Georgia Institute of Technology and PSI, such uncertainty in this comparison was eliminated by using ENDF/B-V data for BOXER calculations at Georgia Tech

  14. Calculations for Adjusting Endogenous Biomarker Levels During Analytical Recovery Assessments for Ligand-Binding Assay Bioanalytical Method Validation.

    Science.gov (United States)

    Marcelletti, John F; Evans, Cindy L; Saxena, Manju; Lopez, Adriana E

    2015-07-01

    It is often necessary to adjust for detectable endogenous biomarker levels in spiked validation samples (VS) and in selectivity determinations during bioanalytical method validation for ligand-binding assays (LBA) with a matrix like normal human serum (NHS). Described herein are case studies of biomarker analyses using multiplex LBA which highlight the challenges associated with such adjustments when calculating percent analytical recovery (%AR). The LBA test methods were the Meso Scale Discovery V-PLEX® proinflammatory and cytokine panels with NHS as test matrix. The NHS matrix blank exhibited varied endogenous content of the 20 individual cytokines before spiking, ranging from undetectable to readily quantifiable. Addition and subtraction methods for adjusting endogenous cytokine levels in %AR calculations are both used in the bioanalytical field. The two methods were compared in %AR calculations following spiking and analysis of VS for cytokines having detectable endogenous levels in NHS. Calculations for %AR obtained by subtracting quantifiable endogenous biomarker concentrations from the respective total analytical VS values yielded reproducible and credible conclusions. The addition method, in contrast, yielded %AR conclusions that were frequently unreliable and discordant with values obtained with the subtraction adjustment method. It is shown that subtraction of assay signal attributable to matrix is a feasible alternative when endogenous biomarkers levels are below the limit of quantitation, but above the limit of detection. These analyses confirm that the subtraction method is preferable over that using addition to adjust for detectable endogenous biomarker levels when calculating %AR for biomarker LBA.

  15. Parameter validation of analytical methods of insecticide residue analyses in foods of animal origin, feed and water.

    Science.gov (United States)

    Debebe, Amsalu; Kuttalam, S

    2011-06-01

    The study was conducted to examine the interrelationship and coherence of analytical parameters in method validation. Recovery, sensitivity, linearity, precision and limits of detection (LOD) were tested in six methods for organochlorine and organophosphate insecticides. Compounds that fell out of the stipulated recovery, 70-120%, in a matrix have concurrently failed to meet the requirements for sensitivity (≥ 0.7), linearity (R² > 0.99) and precision (< 0.2) in the same matrix. Highest LOD was recorded in those compounds and matrices. Different from the conventional point estimate, a new approach was introduced for setting upper and lower confidence limits of the LOD in quantitative analyses.

  16. Validation of analytical methods for the quality control of Naproxen suppositories

    International Nuclear Information System (INIS)

    Rodriguez Hernandez, Yaslenis; Suarez Perez, Yania; Garcia Pulpeiro, Oscar; Hernandez Contreras, Orestes Yuniel

    2011-01-01

    The analysis methods that will be used for the quality control of the future Cuban-made Naproxen suppositories for adults and children were developed for the first time in this paper. One method based on direct ultraviolet spectrophotometry was put forward, which proved to be specific, linear, accurate and precise for the quality control of Naproxen suppositories, taking into account the presence of chromophore groups in their structure. Likewise, the direct semi-aqueous acid-base volumetry method aimed at the quality control of the Naproxen raw material was changed and adapted to the quality control of suppositories. On the basis of the validation process, there was demonstrated the adequate specificity of this method with respect to the formulation components, as well as its linearity, accuracy and precision in 1-3 mg/ml range. The final results were compared and no significant statistical differences among the replicas per each dose were found in both methods; therefore, both may be used in the quality control of Naproxen suppositories

  17. Suspended sediment assessment by combining sound attenuation and backscatter measurements - analytical method and experimental validation

    Science.gov (United States)

    Guerrero, Massimo; Di Federico, Vittorio

    2018-03-01

    The use of acoustic techniques has become common for estimating suspended sediment in water environments. An emitted beam propagates into water producing backscatter and attenuation, which depend on scattering particles concentration and size distribution. Unfortunately, the actual particles size distribution (PSD) may largely affect the accuracy of concentration quantification through the unknown coefficients of backscattering strength, ks2, and normalized attenuation, ζs. This issue was partially solved by applying the multi-frequency approach. Despite this possibility, a relevant scientific and practical question remains regarding the possibility of using acoustic methods to investigate poorly sorted sediment in the spectrum ranging from clay to fine sand. The aim of this study is to investigate the possibility of combining the measurement of sound attenuation and backscatter to determine ζs for the suspended particles and the corresponding concentration. The proposed method is moderately dependent from actual PSD, thus relaxing the need of frequent calibrations to account for changes in ks2 and ζs coefficients. Laboratory tests were conducted under controlled conditions to validate this measurement technique. With respect to existing approaches, the developed method more accurately estimates the concentration of suspended particles ranging from clay to fine sand and, at the same time, gives an indication on their actual PSD.

  18. Analytical Validation of a New Enzymatic and Automatable Method for d-Xylose Measurement in Human Urine Samples

    Directory of Open Access Journals (Sweden)

    Israel Sánchez-Moreno

    2017-01-01

    Full Text Available Hypolactasia, or intestinal lactase deficiency, affects more than half of the world population. Currently, xylose quantification in urine after gaxilose oral administration for the noninvasive diagnosis of hypolactasia is performed with the hand-operated nonautomatable phloroglucinol reaction. This work demonstrates that a new enzymatic xylose quantification method, based on the activity of xylose dehydrogenase from Caulobacter crescentus, represents an excellent alternative to the manual phloroglucinol reaction. The new method is automatable and facilitates the use of the gaxilose test for hypolactasia diagnosis in the clinical practice. The analytical validation of the new technique was performed in three different autoanalyzers, using buffer or urine samples spiked with different xylose concentrations. For the comparison between the phloroglucinol and the enzymatic assays, 224 urine samples of patients to whom the gaxilose test had been prescribed were assayed by both methods. A mean bias of −16.08 mg of xylose was observed when comparing the results obtained by both techniques. After adjusting the cut-off of the enzymatic method to 19.18 mg of xylose, the Kappa coefficient was found to be 0.9531, indicating an excellent level of agreement between both analytical procedures. This new assay represents the first automatable enzymatic technique validated for xylose quantification in urine.

  19. Validation of an analytical method for determining halothane in urine as an instrument for evaluating occupational exposure

    International Nuclear Information System (INIS)

    Gonzalez Chamorro, Rita Maria; Jaime Novas, Arelis; Diaz Padron, Heliodora

    2010-01-01

    The occupational exposure to harmful substances may impose the apparition of determined significative changes in the normal physiology of the organism when the adequate security measures are not taken in time in a working place where the risk may be present. Among the chemical risks that may affect the workers' health are the inhalable anesthetic agents. With the objective to take the first steps for the introduction of an epidemiological surveillance system to this personnel, an analytical method for determining this anesthetic in urine was validated with the instrumental conditions created in our laboratory. To carry out this validation the following parameters were taken into account: specificity, lineament, precision, accuracy, detection limit and quantification limit, and the uncertainty of the method was calculated. In the validation procedure it was found that the technique is specific and precise, the detection limit was of 0,118 μg/L, and of the quantification limit of 0,354 μg/L. The global uncertainty was of 0,243, and the expanded of 0,486. The validated method, together with the posterior introduction of the biological exposure limits, will serve as an auxiliary means of diagnosis which will allow us a periodical control of the personnel exposure

  20. Adequacy and validation of an analytical method for the quantification of lead in chamomile tisanes produced in Costa Rica

    International Nuclear Information System (INIS)

    Blanco Barrantes, Jeimy

    2014-01-01

    An analytical methodology is developed and validated to quantify lead in chamomile tisanes. Lead is quantified by utilizing the technique of flame atomic absorption spectroscopy in three brands of chamomile tisanes sold in Costa Rica to determine its safety and quality based on international standards. A method of sample preparation is established through a comparison of different forms of extraction. The acid digestion extraction method has been the procedure utilized, reaching an average recovery percentage of 97,1%, with a standard deviation of 2,3%. The optimization of the chosen analytical procedure and complete validation is performed. The results obtained in the validation of the analytical procedure have shown that the interval where is generated the best calibration curve in terms of the correlation coefficient and the value of the statistically significant intercept equal to zero, have been the comprised between (0,2-3,2) μg/mL (r 2 =0,9996), corresponding to a range between 20% to 320% of the maximum allowed limit. In addition, the procedure has been adequate in terms of accuracy (average recovery percentage 101,1%) and precision under repeatability and intermediate precision (RSD max. 9,3%) and limit of quantification (0,2551 μg/mL). The safety criterion of World Health Organization (WHO) is determined with respect to the concentration of lead in the analyzed products. The 9 analyzed samples of products to prepare chamomile tisanes have stayed without evidencing concentrations of lead above the limit value of 10 μg/g suggested for medicinal herbs by WHO [es

  1. Analytical method for the identification and assay of 12 phthalates in cosmetic products: application of the ISO 12787 international standard "Cosmetics-Analytical methods-Validation criteria for analytical results using chromatographic techniques".

    Science.gov (United States)

    Gimeno, Pascal; Maggio, Annie-Françoise; Bousquet, Claudine; Quoirez, Audrey; Civade, Corinne; Bonnet, Pierre-Antoine

    2012-08-31

    Esters of phthalic acid, more commonly named phthalates, may be present in cosmetic products as ingredients or contaminants. Their presence as contaminant can be due to the manufacturing process, to raw materials used or to the migration of phthalates from packaging when plastic (polyvinyl chloride--PVC) is used. 8 phthalates (DBP, DEHP, BBP, DMEP, DnPP, DiPP, DPP, and DiBP), classified H360 or H361, are forbidden in cosmetics according to the European regulation on cosmetics 1223/2009. A GC/MS method was developed for the assay of 12 phthalates in cosmetics, including the 8 phthalates regulated. Analyses are carried out on a GC/MS system with electron impact ionization mode (EI). The separation of phthalates is obtained on a cross-linked 5%-phenyl/95%-dimethylpolysiloxane capillary column 30 m × 0.25 mm (i.d.) × 0.25 mm film thickness using a temperature gradient. Phthalate quantification is performed by external calibration using an internal standard. Validation elements obtained on standard solutions, highlight a satisfactory system conformity (resolution>1.5), a common quantification limit at 0.25 ng injected, an acceptable linearity between 0.5 μg mL⁻¹ and 5.0 μg mL⁻¹ as well as a precision and an accuracy in agreement with in-house specifications. Cosmetic samples ready for analytical injection are analyzed after a dilution in ethanol whereas more complex cosmetic matrices, like milks and creams, are assayed after a liquid/liquid extraction using ter-butyl methyl ether (TBME). Depending on the type of cosmetics analyzed, the common limits of quantification for the 12 phthalates were set at 0.5 or 2.5 μg g⁻¹. All samples were assayed using the analytical approach described in the ISO 12787 international standard "Cosmetics-Analytical methods-Validation criteria for analytical results using chromatographic techniques". This analytical protocol is particularly adapted when it is not possible to make reconstituted sample matrices. Copyright © 2012

  2. Validation of an analytical method applicable to study of 1 mg/mL oral Risperidone solution stability

    International Nuclear Information System (INIS)

    Abreu Alvarez, Maikel; Garcia Penna, Caridad Margarita; Martinez Miranda, Lissette

    2010-01-01

    A validated analytical method by high-performance liquid chromatography (HPLC) was applicable to study of 1 mg/mL Risperidone oral solution stability. The above method was linear, accurate, specific and exact. A stability study of the 1 mg/mL Risperidone oral solution was developed determining its expiry date. The shelf life study was conducted for 24 months at room temperature; whereas the accelerated stability study was conducted with product under influence of humidity and temperature; analysis was made during 3 months. Formula fulfilled the quality specifications described in Pharmacopeia. The results of stability according to shelf life after 24 months showed that the product maintains the parameters determining its quality during this time and in accelerated studies there was not significant degradation (p> 0.05) in the product. Under mentioned conditions expiry date was of 2 years

  3. Analytical method development and validation for quantification of uranium by Fourier Transform Infrared Spectroscopy (FTIR) for routine quality control analysis

    International Nuclear Information System (INIS)

    Pereira, Elaine; Silva, Ieda de S.; Gomide, Ricardo G.; Pires, Maria Aparecida F.

    2015-01-01

    This work presents a low cost, simple and new methodology for direct determination uranium in different matrices uranium: organic phase (UO 2 (NO 3 ) 2 .2TBP - uranyl nitrate complex) and aqueous phase (UO 2 (NO 3 ) 2 - NTU - uranyl nitrate), based on Fourier Transform Infrared spectroscopy (FTIR) using KBr pellets technique. The analytical validation is essential to define if a developed methodology is completely adjusted to the objectives that it is destined and is considered one of the main instruments of quality control. The parameters used in the validation process were: selectivity, linearity, limits of detection (LD) and quantitation (LQ), precision (repeatability and intermediate precision), accuracy and robustness. The method for uranium in organic phase (UO 2 (NO 3 ) 2 .2TBP in hexane/embedded in KBr) was linear (r=0.9989) over the range of 1.0 g L -1 a 14.3 g L -1 , LD were 92.1 mg L -1 and LQ 113.1 mg L -1 , precision (RSD < 1.6% and p-value < 0.05), accurate (recovery of 100.1% - 102.9%). The method for uranium aqueous phase (UO 2 (NO 3 )2/embedded in KBr) was linear (r=0.9964) over the range of 5.4 g L -1 a 51.2 g L -1 , LD were 835 mg L -1 and LQ 958 mg L -1 , precision (RSD < 1.0% and p-value < 0.05), accurate (recovery of 99.1% - 102.0%). The FTIR method is robust regarding most of the variables analyzed, as the difference between results obtained under nominal and modified conditions were lower than the critical value for all analytical parameters studied. Some process samples were analyzed in FTIR and compared with gravimetric and x ray fluorescence (XRF) analyses showing similar results in all three methods. The statistical tests (Student-t and Fischer) showed that the techniques are equivalent. (author)

  4. An analytical method for the thermoluminescence growth curve and its validity

    International Nuclear Information System (INIS)

    Sunta, C.M.; Yoshimura, E.M.; Okuno, E.

    1994-01-01

    The radiative recombination probability P of a carrier released from an active TL trap is computed for the case when the TL traps are interactive with the deep traps. It is shown that the value of P remains constant throughout the TL readout heating when the capture coefficients of the recombination centre and the deep trap are equal. When these coefficients are not equal, P undergoes change but its variation with temperature is still insignificant under a wide variety of conditions. A net value P applicable to the area of the glow curve is calculated and compared with the initial (when heating is begun) value of P, which is used in the analytical expression for the area of the glow curve. (Author)

  5. Analytical Method Validation of High-Performance Liquid Chromatography and Stability-Indicating Study of Medroxyprogesterone Acetate Intravaginal Sponges

    Directory of Open Access Journals (Sweden)

    Nidal Batrawi

    2017-02-01

    Full Text Available Medroxyprogesterone acetate is widely used in veterinary medicine as intravaginal dosage for the synchronization of breeding cycle in ewes and goats. The main goal of this study was to develop reverse-phase high-performance liquid chromatography method for the quantification of medroxyprogesterone acetate in veterinary vaginal sponges. A single high-performance liquid chromatography/UV isocratic run was used for the analytical assay of the active ingredient medroxyprogesterone. The chromatographic system consisted of a reverse-phase C18 column as the stationary phase and a mixture of 60% acetonitrile and 40% potassium dihydrogen phosphate buffer as the mobile phase; the pH was adjusted to 5.6. The method was validated according to the International Council for Harmonisation (ICH guidelines. Forced degradation studies were also performed to evaluate the stability-indicating properties and specificity of the method. Medroxyprogesterone was eluted at 5.9 minutes. The linearity of the method was confirmed in the range of 0.0576 to 0.1134 mg/mL ( R 2 > 0.999. The limit of quantification was shown to be 3.9 µg/mL. Precision and accuracy ranges were found to be %RSD <0.2 and 98% to 102%, respectively. Medroxyprogesterone capacity factor value of 2.1, tailing factor value of 1.03, and resolution value of 3.9 were obtained in accordance with ICH guidelines. Based on the obtained results, a rapid, precise, accurate, sensitive, and cost-effective analysis procedure was proposed for quantitative determination of medroxyprogesterone in vaginal sponges. This analytical method is the only available method to analyse medroxyprogesterone in veterinary intravaginal dosage form.

  6. Validation of an analytical method for the determination in serum of ...

    African Journals Online (AJOL)

    Background: Inter-individual variability in clinical response to psychotropic drugs remains problematic in management of mental illnesses. The patients differ in their ability to absorb, distribute, metabolize and eliminate drugs due to genetic peculiarities, concurrent disease, age, or concomitant medication. Methods: A simple ...

  7. Use of reference materials for validating analytical methods. Applied to the determination of As, Co, Na, Hg, Se and Fe using neutron activation analysis

    International Nuclear Information System (INIS)

    Munoz, L; Andonie, O; Kohnenkamp, I

    2000-01-01

    The main purpose of an analytical laboratory is to provide reliable information on the nature and composition of the materials submitted for analysis. This purpose can only be attained if analytical methodologies that have the attributes of accuracy, precision, specificity and sensitivity, among others, are used. The process by which these attributes are evaluated is called validation of the analytical method. The Chilean Nuclear Energy Commission's Neutron Activation Analysis Laboratory is applying a quality guarantee program to ensure the quality of its analytical results, which aims, as well, to attain accreditation for some of its measurements. Validation of the analytical methodologies used is an essential part of applying this program. There are many forms of validation, from comparison with reference techniques to participation in inter-comparison rounds. Certified reference materials were used in this work in order to validate the application of neutron activation analysis in determining As, Co, Na, Hg, Se and Fe in shellfish samples. The use of reference materials was chosen because it is a simple option that easily detects sources of systematic errors. Neutron activation analysis is an instrumental analytical method that does not need chemical treatment and that is based on processes which take place in the nuclei of atoms, making the matrix effects unimportant and different biological reference materials can be used. The following certified reference materials were used for validating the method used: BCR human hair 397, NRCC dogfish muscle DORM-2, NRCC -dogfish liver DOLT-2, NIST - oyster tissue 1566, NIES - mussel 6 and BCR - tuna fish 464. The reference materials were analyzed using the procedure developed for the shellfish samples and the above-mentioned elements were determined. With the results obtained, the parameters of accuracy, precision, detection limit, quantification limit and uncertainty associated with the method were determined for each

  8. Validation of an analytical method for the quantitative determination of selenium in bacterial biomass by ultraviolet-visible spectrophotometry.

    Science.gov (United States)

    Mörschbächer, Ana Paula; Dullius, Anja; Dullius, Carlos Henrique; Bandt, Cassiano Ricardo; Kuhn, Daniel; Brietzke, Débora Tairini; Malmann Kuffel, Fernando José; Etgeton, Henrique Pretto; Altmayer, Taciélen; Gonçalves, Tamara Engelmann; Oreste, Eliézer Quadro; Ribeiro, Anderson Schwingel; de Souza, Claucia Fernanda Volken; Hoehne, Lucélia

    2018-07-30

    The present paper describes the validation of a spectrophotometry method involving molecular absorption in the visible ultraviolet-visible (UV-Vis) region for selenium (Se) determination in the bacterial biomass produced by lactic acid bacteria (LAB). The method was found to be suitable for the target application and presented a linearity range from 0.025 to 0.250 mg/L Se. The angular and linear coefficients of the linear equation were 1.0678 and 0.0197 mg/L Se, respectively, and the linear correlation coefficient (R 2 ) was 0.9991. Analyte recovery exceeded 96% with a relative standard deviation (RSD) below 3%. The Se contents in LAB ranged from 0.01 to 20 mg/g. The Se contents in the bacterial biomass determined by UV-Vis were not significantly different (p > 0.05) those determined by graphite furnace atomic absorption spectrometry. Thus, Se can be quantified in LAB biomass using this relatively simpler technique. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Analytical method validation of GC-FID for the simultaneous measurement of hydrocarbons (C2-C4) in their gas mixture

    OpenAIRE

    Oman Zuas; Harry budiman; Muhammad Rizky Mulyana

    2016-01-01

    An accurate gas chromatography coupled to a flame ionization detector (GC-FID) method was validated for the simultaneous analysis of light hydrocarbons (C2-C4) in their gas mixture. The validation parameters were evaluated based on the ISO/IEC 17025 definition including method selectivity, repeatability, accuracy, linearity, limit of detection (LOD), limit of quantitation (LOQ), and ruggedness. Under the optimum analytical conditions, the analysis of gas mixture revealed that each target comp...

  10. Validation of an analytical method for the determination of spiramycin, virginiamycin and tylosin in feeding-stuffs bij thin-layer chromatography and bio-autography

    NARCIS (Netherlands)

    Vincent, U.; Gizzi, G.; Holst, von C.; Jong, de J.; Michard, J.

    2007-01-01

    An inter-laboratory validation was carried out to determine the performance characteristics of an analytical method based on thin-layer chromatography (TLC) coupled to microbiological detection (bio-autography) for screening feed samples for the presence of spiramycin, tylosin and virginiamycin.

  11. Development and validation of a multi-analyte method for the regulatory control of carotenoids used as feed additives in fish and poultry feed.

    Science.gov (United States)

    Vincent, Ursula; Serano, Federica; von Holst, Christoph

    2017-08-01

    Carotenoids are used in animal nutrition mainly as sensory additives that favourably affect the colour of fish, birds and food of animal origin. Various analytical methods exist for their quantification in compound feed, reflecting the different physico-chemical characteristics of the carotenoid and the corresponding feed additives. They may be natural products or specific formulations containing the target carotenoids produced by chemical synthesis. In this study a multi-analyte method was developed that can be applied to the determination of all 10 carotenoids currently authorised within the European Union for compound feedingstuffs. The method functions regardless of whether the carotenoids have been added to the compound feed via natural products or specific formulations. It is comprised of three steps: (1) digestion of the feed sample with an enzyme; (2) pressurised liquid extraction; and (3) quantification of the analytes by reversed-phase HPLC coupled to a photodiode array detector in the visible range. The method was single-laboratory validated for poultry and fish feed covering a mass fraction range of the target analyte from 2.5 to 300 mg kg - 1 . The following method performance characteristics were obtained: the recovery rate varied from 82% to 129% and precision expressed as the relative standard deviation of intermediate precision varied from 1.6% to 15%. Based on the acceptable performance obtained in the validation study, the multi-analyte method is considered fit for the intended purpose.

  12. Bio-analytical method development and validation of Rasagiline by high performance liquid chromatography tandem mass spectrometry detection and its application to pharmacokinetic study

    OpenAIRE

    Ravi Kumar Konda; Babu Rao Chandu; B.R. Challa; Chandrasekhar B. Kothapalli

    2012-01-01

    The most suitable bio-analytical method based on liquidâliquid extraction has been developed and validated for quantification of Rasagiline in human plasma. Rasagiline-13C3 mesylate was used as an internal standard for Rasagiline. Zorbax Eclipse Plus C18 (2.1 mmÃ50 mm, 3.5 μm) column provided chromatographic separation of analyte followed by detection with mass spectrometry. The method involved simple isocratic chromatographic condition and mass spectrometric detection in the positive ion...

  13. Development and validation of an analytical method for quality control and the stability of the eyedrops 10 % Phenylephrine and the 1 % Tropicamide

    International Nuclear Information System (INIS)

    Garcia Penna, Caridad Margarita; Botet Garcia, Martha; Troche Concepcion, Yenilen

    2011-01-01

    An analytical high-performance liquid chromatography method was developed and validated applicable to quality control and to stability study of 10 % phenylephrine plus eyedrops 1 % tropicamide. To quantify simultaneously both active principles in the finished product, separation was carried out through a Lichrosorb RP-18 (15 μm) (260 x 4 mm) column chromatography, with ultraviolet detection at 253 nm using the mobile phase composed of methanol: distilled water (1:1), with 1.1 g of sodium 1-octasulfanate by litre and pH fitted to 3.0 with phosphoric acid and the quantification of this front to a reference sample using the external standard method. The analytical method developed was linear, precise, specific and accurate in the rank of study concentrations, established for the quality control and stability study of the finished product since there were not analytical methods designed for these aims

  14. Multicenter Analytical Validation of Aβ40 Immunoassays

    Directory of Open Access Journals (Sweden)

    Linda J. C. van Waalwijk van Doorn

    2017-07-01

    Full Text Available BackgroundBefore implementation in clinical practice, biomarker assays need to be thoroughly analytically validated. There is currently a strong interest in implementation of the ratio of amyloid-β peptide 1-42 and 1-40 (Aβ42/Aβ40 in clinical routine. Therefore, in this study, we compared the analytical performance of six assays detecting Aβ40 in cerebrospinal fluid (CSF in six laboratories according to a recently standard operating procedure (SOP developed for implementation of ELISA assays for clinical routine.MethodsAβ40 assays of six vendors were validated in up to three centers per assay according to recently proposed international consensus validation protocols. The performance parameters included sensitivity, precision, dilutional linearity, recovery, and parallelism. Inter-laboratory variation was determined using a set of 20 CSF samples. In addition, test results were used to critically evaluate the SOPs that were used to validate the assays.ResultsMost performance parameters of the different Aβ40 assays were similar between labs and within the predefined acceptance criteria. The only exceptions were the out-of-range results of recovery for the majority of experiments and of parallelism by three laboratories. Additionally, experiments to define the dilutional linearity and hook-effect were not executed correctly in part of the centers. The inter-laboratory variation showed acceptable low levels for all assays. Absolute concentrations measured by the assays varied by a factor up to 4.7 for the extremes.ConclusionAll validated Aβ40 assays appeared to be of good technical quality and performed generally well according to predefined criteria. A novel version of the validation SOP is developed based on these findings, to further facilitate implementation of novel immunoassays in clinical practice.

  15. Validation of a UV-spectrophotometric analytical method for determination of LPSF/AC04 from inclusion complex and liposomes

    Directory of Open Access Journals (Sweden)

    Rafaela Siqueira Ferraz

    2015-03-01

    Full Text Available The aim of this study was to develop and validate a UV spectrophotometric method for determination of LPSF/AC04 from inclusion complex and encapsulated into liposomes. The validation parameters were determined according to the International Conference on Harmonisation (ICH and National Health Surveillance Agency (ANVISA guidelines. LPSF/AC04 was determined at 250 nm in methanol by a UV spectrophotometric method, exhibiting linearity in the range from 0.3 to 2 µg.mL−1 (Absorbance=0.18068 x [LPSF/AC04 µg.mL-1] + 0.00348, (r2=0.9995. The limits of detection and quantification were 0.047µg.mL−1 and 0.143µg.mL−1, respectively. The method was accurate, precise, reproducible and robust since all the samples analyzed had coefficient of variation of less than 5% and no statistically significant difference between theoretical and practical concentrations was detected. Thus, a rapid, simple, low cost and sensitive spectrophotometric method was developed and validated for determining the content of inclusion complex and liposomes containing LPSF/AC04.

  16. Development and validation of a simple high-performance liquid chromatography analytical method for simultaneous determination of phytosterols, cholesterol and squalene in parenteral lipid emulsions.

    Science.gov (United States)

    Novak, Ana; Gutiérrez-Zamora, Mercè; Domenech, Lluís; Suñé-Negre, Josep M; Miñarro, Montserrat; García-Montoya, Encarna; Llop, Josep M; Ticó, Josep R; Pérez-Lozano, Pilar

    2018-02-01

    A simple analytical method for simultaneous determination of phytosterols, cholesterol and squalene in lipid emulsions was developed owing to increased interest in their clinical effects. Method development was based on commonly used stationary (C 18 , C 8 and phenyl) and mobile phases (mixtures of acetonitrile, methanol and water) under isocratic conditions. Differences in stationary phases resulted in peak overlapping or coelution of different peaks. The best separation of all analyzed compounds was achieved on Zorbax Eclipse XDB C 8 (150 × 4.6 mm, 5 μm; Agilent) and ACN-H 2 O-MeOH, 80:19.5:0.5 (v/v/v). In order to achieve a shorter time of analysis, the method was further optimized and gradient separation was established. The optimized analytical method was validated and tested for routine use in lipid emulsion analyses. Copyright © 2017 John Wiley & Sons, Ltd.

  17. Analytical method development and validation of spectrofluorimetric and spectrophotometric determination of some antimicrobial drugs in their pharmaceuticals

    Science.gov (United States)

    Ibrahim, F.; Wahba, M. E. K.; Magdy, G.

    2018-01-01

    In this study, three novel, sensitive, simple and validated spectrophotometric and spectrofluorimetric methods have been proposed for estimation of some important antimicrobial drugs. The first two methods have been proposed for estimation of two important third-generation cephalosporin antibiotics namely, cefixime and cefdinir. Both methods were based on condensation of the primary amino group of the studied drugs with acetyl acetone and formaldehyde in acidic medium. The resulting products were measured by spectrophotometric (Method I) and spectrofluorimetric (Method II) tools. Regarding method I, the absorbance was measured at 315 nm and 403 nm with linearity ranges of 5.0-140.0 and 10.0-100.0 μg/mL for cefixime and cefdinir, respectively. Meanwhile in method II, the produced fluorophore was measured at λem 488 nm or 491 nm after excitation at λex 410 nm with linearity ranges of 0.20-10.0 and 0.20-36.0 μg/mL for cefixime and cefdinir, respectively. On the other hand, method III was devoted to estimate nifuroxazide spectrofluorimetrically depending on formation of highly fluorescent product upon reduction of the studied drug with Zinc powder in acidic medium. Measurement of the fluorescent product was carried out at λem 335 nm following excitation at λex 255 nm with linearity range of 0.05 to 1.6 μg/mL. The developed methods were subjected to detailed validation procedure, moreover they were used for the estimation of the concerned drugs in their pharmaceuticals. It was found that there is a good agreement between the obtained results and those obtained by the reported methods.

  18. Optimization of instrumental neutron activation analysis method by means of 2k experimental design technique aiming the validation of analytical procedures

    International Nuclear Information System (INIS)

    Petroni, Robson; Moreira, Edson G.

    2013-01-01

    In this study optimization of procedures and standardization of Instrumental Neutron Activation Analysis (INAA) methods were carried out for the determination of the elements arsenic, chromium, cobalt, iron, rubidium, scandium, selenium and zinc in biological materials. The aim is to validate the analytical methods for future accreditation at the National Institute of Metrology, Quality and Technology (INMETRO). The 2 k experimental design was applied for evaluation of the individual contribution of selected variables of the analytical procedure in the final mass fraction result. Samples of Mussel Tissue Certified Reference Material and multi-element standards were analyzed considering the following variables: sample decay time, counting time and sample distance to detector. The standard multi-element concentration (comparator standard), mass of the sample and irradiation time were maintained constant in this procedure. By means of the statistical analysis and theoretical and experimental considerations it was determined the optimized experimental conditions for the analytical methods that will be adopted for the validation procedure of INAA methods in the Neutron Activation Analysis Laboratory (LAN) of the Research Reactor Center (CRPq) at the Nuclear and Energy Research Institute (IPEN - CNEN/SP). Optimized conditions were estimated based on the results of z-score tests, main effect and interaction effects. The results obtained with the different experimental configurations were evaluated for accuracy (precision and trueness) for each measurement. (author)

  19. Bio-analytical method development and validation of Rasagiline by high performance liquid chromatography tandem mass spectrometry detection and its application to pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Konda

    2012-10-01

    Full Text Available The most suitable bio-analytical method based on liquid–liquid extraction has been developed and validated for quantification of Rasagiline in human plasma. Rasagiline-13C3 mesylate was used as an internal standard for Rasagiline. Zorbax Eclipse Plus C18 (2.1 mm×50 mm, 3.5 μm column provided chromatographic separation of analyte followed by detection with mass spectrometry. The method involved simple isocratic chromatographic condition and mass spectrometric detection in the positive ionization mode using an API-4000 system. The total run time was 3.0 min. The proposed method has been validated with the linear range of 5–12000 pg/mL for Rasagiline. The intra-run and inter-run precision values were within 1.3%–2.9% and 1.6%–2.2% respectively for Rasagiline. The overall recovery for Rasagiline and Rasagiline-13C3 mesylate analog was 96.9% and 96.7% respectively. This validated method was successfully applied to the bioequivalence and pharmacokinetic study of human volunteers under fasting condition. Keywords: High performance liquid chromatography, Mass spectrometry, Rasagiline, Liquid–liquid extraction

  20. Bio-analytical method development and validation of Rasagiline by high performance liquid chromatography tandem mass spectrometry detection and its application to pharmacokinetic study.

    Science.gov (United States)

    Konda, Ravi Kumar; Chandu, Babu Rao; Challa, B R; Kothapalli, Chandrasekhar B

    2012-10-01

    The most suitable bio-analytical method based on liquid-liquid extraction has been developed and validated for quantification of Rasagiline in human plasma. Rasagiline- 13 C 3 mesylate was used as an internal standard for Rasagiline. Zorbax Eclipse Plus C18 (2.1 mm×50 mm, 3.5 μm) column provided chromatographic separation of analyte followed by detection with mass spectrometry. The method involved simple isocratic chromatographic condition and mass spectrometric detection in the positive ionization mode using an API-4000 system. The total run time was 3.0 min. The proposed method has been validated with the linear range of 5-12000 pg/mL for Rasagiline. The intra-run and inter-run precision values were within 1.3%-2.9% and 1.6%-2.2% respectively for Rasagiline. The overall recovery for Rasagiline and Rasagiline- 13 C 3 mesylate analog was 96.9% and 96.7% respectively. This validated method was successfully applied to the bioequivalence and pharmacokinetic study of human volunteers under fasting condition.

  1. Volatile composition of Merlot red wine and its contribution to the aroma: optimization and validation of analytical method.

    Science.gov (United States)

    Arcari, Stefany Grützmann; Caliari, Vinicius; Sganzerla, Marla; Godoy, Helena Teixeira

    2017-11-01

    A methodology for the determination of volatile compounds in red wine using headspace solid phase microextraction (HS-SPME) combined with gas chromatography-ion trap/ mass spectrometry (GC-IT/MS) and flame ionization detector (GC -FID) was developed, validated and applied to a sample of Brazilian red wine. The optimization strategy was conducted using the Plackett-Burman design for variable selection and central composite rotational design (CCRD). The response surface methodology showed that the performance of the extraction of the volatile compounds using divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber is improved with no sample dilution, the addition of 30% NaCl, applying an extraction temperature of 56°C and extraction time of 55min. The qualitative method allowed the extraction and identification of 60 volatile compounds in the sample studied, notably the classes of esters, alcohols, and fatty acids. Furthermore, the method was successfully validated for the quantification of 55 volatile compounds of importance in wines and applied to twelve samples of Merlot red wine from South of Brazil. The calculation of the odor activity value (OAV) showed the most important components of the samples aroma. Ethyl isovalerate, ethyl hexanoate, 1-hexanol, octanoic acid and ethyl cinnamate had the greatest contribution to the aroma of the wines analyzed, which is predominantly fruity with the presence of herbal and fatty odors. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Development and validation of a HPLC analytical assay method for efavirenz tablets: a medicine for HIV infections

    Directory of Open Access Journals (Sweden)

    Osnir de Sá Viana

    2011-03-01

    Full Text Available Efavirenz is a reverse transcriptase non analog nucleoside inhibitor used to treat HIV infections. A simple assay method by high performance liquid chromatography was developed and validated for efavirenz tablets. The physical chemical characteristics of efavirenz were investigated to developing the method. The method was validated observing the parameters described in USP 29. Analyses were performed by an ultraviolet detector at a 252 nm wavelength, on a reverse-phase column (C18, 250 mm x 3.9 mm, 10 μm, using an isocratic mobile phase containing acetonitrile/water/orthophosphoric acid (70:30:0.1. The validation parameters used were: selectivity, linearity, precision, accuracy, robustness, detection and quantification limits, and all resulting data were treated by a statistical method. The results obtained confirmed an alternative assay method for efavirenz tablets adequate for routine industrial use.O efavirenz é um inibidor não análogo de nucleosídeo da transcriptase reversa, utilizado no tratamento da infecção por HIV. Um método simples, por cromatografia líquida de alta eficiência, foi desenvolvido e validado para quantificação do efavirenz em comprimidos. O desenvolvimento do método levou em consideração as características físico-químicas do efavirenz. O método foi validado seguindo os parâmetros da USP 29. A análise foi realizada por meio de detector ultravioleta, utilizando um comprimento de onda de 252 nm, com coluna de fase reversa (C18, 250 mm x 3.9 mm, 10 μm e fase móvel isocrática contendo acetonitrila/água/ácido ortofosfórico (70: 30: 0.1. Os critérios usados para validação foram: seletividade, linearidade, precisão, exatidão, robustez e limites de detecção e quantificação do método. Foi utilizado método estatístico em todas as etapas do processo de validação. Os resultados obtidos mostraram que o método é uma alternativa para quantificação do efavirenz em comprimidos, tornando vi

  3. Phenolic compounds involved in grafting incompatibility of Vitis spp: development and validation of an analytical method for their quantification.

    Science.gov (United States)

    Canas, Sara; Assunção, Maria; Brazão, João; Zanol, Geni; Eiras-Dias, José Eduardo

    2015-01-01

    Graft incompatibility of Vitis spp is an unresolved worldwide problem with important economic consequences. Grafting comprises a complex set of morphological and physiological alterations, in which the phenolic compounds seem to be strongly involved. Therefore, a detailed analysis and recognition of structural phenolic compounds diversity in the two partners of a Vitis graft is of great importance to evaluate their role as markers of graft establishment. To optimise a sample extraction method, and to develop and validate a high-performance liquid chromatography (HPLC) method for the simultaneous determination of phenolic acids and flavonols in the graft union so as to understand their behaviour in the metabolism of the scion-rootstock system, using compatible and incompatible combinations of a Syrah cultivar and two rootstocks (R110 and SO4). Sixty extracts of Vitis grafting tissues were prepared and analysed by HPLC for the qualitative and quantitative determination of their phenolic profile. Among the phenolic compounds identified in the samples, one benzoic acid (gallic acid), three cinnamic acids (caffeic acid, ferulic acid and sinapic acid) and two flavonols (catechin and epicatechin) are potentially suitable as markers of graft incompatibility. The method developed presents good performance and lends itself readily for application in routine analysis of the phenolic composition of Vitis grafting tissues to distinguish compatible and incompatible combinations in the graft callusing stage. Copyright © 2014 John Wiley & Sons, Ltd.

  4. Analytical Method Validation and Determination of Pyridoxine, Nicotinamide, and Caffeine in Energy Drinks Using Thin Layer Chromatography-Densitometry

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    Florentinus Dika Octa Riswanto

    2015-03-01

    Full Text Available Food supplement which contains vitamins and stimulants such as caffeine were classified as energy drink. TLC-densitometry method was chosen to determine the pyridoxine, nicotinamide, and caffeine in the energy drink sample. TLC plates of silica gel 60 F254 was used as the stationary phase and methanol : ethyl acetate : ammonia 25% (134:77:10 was used as the mobile phase. The correlation coefficient for each pyridoxine, nicotinamide, and caffeine were 0.9982, 0.9997, and 0.9966, respectively. Detection and quantitation limits of from the three analytes were 4.05 and 13.51 µg/mL; 13.15 and 43.83 µg/mL; 5.43 and 18.11 µg/mL, respectively. The recovery of pyridoxine, nicotinamide, and caffeine were within the required limit range of 95-105%. The percent of RSD were below the limit value of 5.7% for caffeine and nicotinamide and 8% for pyridoxine. The content amount of pyridoxine in the sample 1 and 2 were 33.59 ± 0.981 and 30.29 ± 2.061 µg/mL, respectively. The content amount of nicotinamide in the sample 1 and 2 were 106.53 ± 3.521 and 98.20 ± 3.648 µg/mL, respectively. The content amount of caffeine in the sample 1 and 2 were 249.50 ± 5.080 and 252.80 ± 2.640 µg/mL, respectively. Robustness test results showed that the most optimal method conditions should be applied for the analysis.

  5. Analytical method validation of GC-FID for the simultaneous measurement of hydrocarbons (C2-C4 in their gas mixture

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    Oman Zuas

    2016-09-01

    Full Text Available An accurate gas chromatography coupled to a flame ionization detector (GC-FID method was validated for the simultaneous analysis of light hydrocarbons (C2-C4 in their gas mixture. The validation parameters were evaluated based on the ISO/IEC 17025 definition including method selectivity, repeatability, accuracy, linearity, limit of detection (LOD, limit of quantitation (LOQ, and ruggedness. Under the optimum analytical conditions, the analysis of gas mixture revealed that each target component was well-separated with high selectivity property. The method was also found to be precise and accurate. The method linearity was found to be high with good correlation coefficient values (R2 ≥ 0.999 for all target components. It can be concluded that the GC-FID developed method is reliable and suitable for determination of light C2-C4 hydrocarbons (including ethylene, propane, propylene, isobutane, and n-butane in their gas mixture. The validated method has successfully been applied to the estimation of hydrocarbons light C2-C4 hydrocarbons in natural gas samples, showing high performance repeatability with relative standard deviation (RSD less than 1.0% and good selectivity with no interference from other possible components could be observed.

  6. Development and validation of an analytical method for the extraction and quantification of soluble sulfates in red clay

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    V. I. Cáceres

    2015-09-01

    Full Text Available AbstractIn this work a fast and environmentally friendly method for the extraction and quantification of soluble sulphates in red clay using microwave assisted extraction (MAE and determination by turbidimetry was developed and validated. The favorable conditions for the extraction of soluble sulphates in red clay by MAE were: 1 g of sample, with particle size of 63μm, dissolved in 50 mL of distilled water, it was extracted using a microwave oven with 70% of power during 5 min, later the sample was centrifuged during 5 min and then filtered. The soluble sulphates in red clays were quantified at 420 nm. The procedure proposed showed linear behaviour in the tested rank (5-7000 mg SO42-/kg of clay with R2 0.9993. The limits of detection and quantification were 4.30 and 14.33 mg/kg, respectively, with a variation coefficient of 1.41%. The method proposed in this work allows to determine soluble sulphates in red clay with a recovery of 94%.

  7. Sewage-based epidemiology in monitoring the use of new psychoactive substances: Validation and application of an analytical method using LC-MS/MS.

    Science.gov (United States)

    Kinyua, Juliet; Covaci, Adrian; Maho, Walid; McCall, Ann-Kathrin; Neels, Hugo; van Nuijs, Alexander L N

    2015-09-01

    Sewage-based epidemiology (SBE) employs the analysis of sewage to detect and quantify drug use within a community. While SBE has been applied repeatedly for the estimation of classical illicit drugs, only few studies investigated new psychoactive substances (NPS). These compounds mimic effects of illicit drugs by introducing slight modifications to chemical structures of controlled illicit drugs. We describe the optimization, validation, and application of an analytical method using liquid chromatography coupled to positive electrospray tandem mass spectrometry (LC-ESI-MS/MS) for the determination of seven NPS in sewage: methoxetamine (MXE), butylone, ethylone, methylone, methiopropamine (MPA), 4-methoxymethamphetamine (PMMA), and 4-methoxyamphetamine (PMA). Sample preparation was performed using solid-phase extraction (SPE) with Oasis MCX cartridges. The LC separation was done with a HILIC (150 x 3 mm, 5 µm) column which ensured good resolution of the analytes with a total run time of 19 min. The lower limit of quantification (LLOQ) was between 0.5 and 5 ng/L for all compounds. The method was validated by evaluating the following parameters: sensitivity, selectivity, linearity, accuracy, precision, recoveries and matrix effects. The method was applied on sewage samples collected from sewage treatment plants in Belgium and Switzerland in which all investigated compounds were detected, except MPA and PMA. Furthermore, a consistent presence of MXE has been observed in most of the sewage samples at levels higher than LLOQ. Copyright © 2015 John Wiley & Sons, Ltd.

  8. Validation of an analytical method for the determination of aldehydes and acetone present in the ambient air at the metropolitan area of Costa Rica

    International Nuclear Information System (INIS)

    Rojas Marin, Jose Felix

    2010-01-01

    The analytical method validation has been conducted for the simultaneous determination of 15 carbonyl compounds, the main aldehydes and ketones present in ambient air. The compounds have been captured on cartridges packed with silica gel impregnated with 2.4-dinitrophenylhydrazine (DNPH) at a constant flow of about 1 lmin -1 . Carbonyl compounds present have formed the respective products, which are then eluted with acetonitrile (solid phase extraction). The extracts were analyzed by the technique of high resolution liquid chromatography with ultraviolet detector at a wavelength of 360 nm. The following results were obtained during method validation: linearity from 0.03 mgl -1 to 15 mgl -1 , limits of detection and quantification of 0.02 mgl -1 and 0.06 mgl -1 , the accuracy no significant bias at a confidence level of 95%, accuracy for repeatability and producibility of the analytical method are around 1%. Two sampling campaigns were made in dry and rainy seasons of 2009 for areas of San Jose, Heredia and Belen. The predominant compounds were found to be acetone, acetaldehyde and the formaldehyde was the most abundant in the city of San Jose, others do not have significant amounts, so there is strong correlation between formaldehyde and acetaldehyde suggesting that stem from a common source, possibly vehicle emissions. (author) [es

  9. Validation of analytical methods in GMP: the disposable Fast Read 102® device, an alternative practical approach for cell counting

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    Gunetti Monica

    2012-05-01

    Full Text Available Abstract Background The quality and safety of advanced therapy products must be maintained throughout their production and quality control cycle to ensure their final use in patients. We validated the cell count method according to the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use and European Pharmacopoeia, considering the tests’ accuracy, precision, repeatability, linearity and range. Methods As the cell count is a potency test, we checked accuracy, precision, and linearity, according to ICH Q2. Briefly our experimental approach was first to evaluate the accuracy of Fast Read 102® compared to the Bürker chamber. Once the accuracy of the alternative method was demonstrated, we checked the precision and linearity test only using Fast Read 102®. The data were statistically analyzed by average, standard deviation and coefficient of variation percentages inter and intra operator. Results All the tests performed met the established acceptance criteria of a coefficient of variation of less than ten percent. For the cell count, the precision reached by each operator had a coefficient of variation of less than ten percent (total cells and under five percent (viable cells. The best range of dilution, to obtain a slope line value very similar to 1, was between 1:8 and 1:128. Conclusions Our data demonstrated that the Fast Read 102® count method is accurate, precise and ensures the linearity of the results obtained in a range of cell dilution. Under our standard method procedures, this assay may thus be considered a good quality control method for the cell count as a batch release quality control test. Moreover, the Fast Read 102® chamber is a plastic, disposable device that allows a number of samples to be counted in the same chamber. Last but not least, it overcomes the problem of chamber washing after use and so allows a cell count in a clean environment such as that in a

  10. Analytical method (HPLC, validation used for identification and assay of the pharmaceutical active ingredient, Tylosin tartrate for veterinary use and its finite product Tilodem 50, hydrosoluble powder

    Directory of Open Access Journals (Sweden)

    Maria Neagu

    2010-12-01

    Full Text Available In SC DELOS IMPEX ’96 SRL the quality of the active pharmaceutical ingredient (API for the finite product Tilodem 50 - hydrosoluble powder was acomkplished in the respect of last European Pharmacopoeia.The method for analysis used in this purpose was the compendial method „Tylosin tartrate for veterinary use” in EurPh. in vigour edition and represent a variant developed and validation „in house”.The parameters which was included in the methodology validation for chromatographic method are the followings: Selectivity, Linearity, Linearity range, Detection and Quantification limits, Precision, Repeatability (intra day, Inter-Day Reproductibility, Accuracy, Robustness, Solutions’ stability and System suitability. According to the European Pharmacopoeia, the active pharmaceutical ingredient is consistent, in terms of quality, if it contains Tylosin A - minimum 80% and the amount of Tylosin A, B, C, D, at minimum 95%. Identification and determination of each component separately (Tylosin A, B, C, D is possible by chromatographic separation-HPLC. Validation of analytical methods is presented below.

  11. Validation of an analytical method for the determination of polycyclic aromatic hydrocarbons by high efficiency liquid chromatography in PM10 and PM2,5 particles

    International Nuclear Information System (INIS)

    Herrera Murillo, Jorge; Chaves Villalobos, Maria del Carmen

    2012-01-01

    An analytical method was validated for polycyclic aromatic hydrocarbons in PM10 and PM2,5 particles collected from air by high performance liquid chromatography (HPLC) was validated. The PAHs analyzed in the methodology include: Naphthalene, Acenaphthylene, Fluorene, Acenaphthene, Phenanthrene, Anthracene, fluoranthene, pyrene, Benzo (a)anthracene, Chrysene, Benzo (b)fluoranthene, Benzo (k)fluoranthene, Benzo (a)pyrene, Dibenzo (a, h)anthracene, Benzo (g, h, i)perylene and Indeno (1,2,3-CD)pyrene. For these compounds, the detection limit and quantification limit have been between 0,02 and 0,1 mg/l. An equipment DIONEX, ICS 3000 model is used, that has two in series detectors: one ultraviolet model VWD-1, and fluorescence detector, model RF-2000, separating the different absorption and emission signals for proper identification of individual compounds. For all the compounds analyzed, the recovery factor has found not significantly different from each other and the repeatability and reproducibility has been to be suitable for an analytical method, especially for the lighter PAHs. (author) [es

  12. Validated spectroscopic methods for determination of anti-histaminic drug azelastine in pure form: Analytical application for quality control of its pharmaceutical preparations

    Science.gov (United States)

    El-Masry, Amal A.; Hammouda, Mohammed E. A.; El-Wasseef, Dalia R.; El-Ashry, Saadia M.

    2018-02-01

    Two simple, sensitive, rapid, validated and cost effective spectroscopic methods were established for quantification of antihistaminic drug azelastine (AZL) in bulk powder as well as in pharmaceutical dosage forms. In the first method (A) the absorbance difference between acidic and basic solutions was measured at 228 nm, whereas in the second investigated method (B) the binary complex formed between AZL and Eosin Y in acetate buffer solution (pH 3) was measured at 550 nm. Different criteria that have critical influence on the intensity of absorption were deeply studied and optimized so as to achieve the highest absorption. The proposed methods obeyed Beer's low in the concentration range of (2.0-20.0 μg·mL- 1) and (0.5-15.0 μg·mL- 1) with % recovery ± S.D. of (99.84 ± 0.87), (100.02 ± 0.78) for methods (A) and (B), respectively. Furthermore, the proposed methods were easily applied for quality control of pharmaceutical preparations without any conflict with its co-formulated additives, and the analytical results were compatible with those obtained by the comparison one with no significant difference as insured by student's t-test and the variance ratio F-test. Validation of the proposed methods was performed according the ICH guidelines in terms of linearity, limit of quantification, limit of detection, accuracy, precision and specificity, where the analytical results were persuasive. The absorption spectrum of AZL (16 μg·mL- 1) in 0.1 M HCl. The absorption spectrum of AZL (16 μg·mL- 1) in 0.1 M NaOH. The difference absorption spectrum of AZL (16 μg·mL- 1) in 0.1 M NaOH vs 0.1 M HCl. The absorption spectrum of eosin binary complex with AZL (10 μg·mL- 1).

  13. Validated spectroscopic methods for determination of anti-histaminic drug azelastine in pure form: Analytical application for quality control of its pharmaceutical preparations.

    Science.gov (United States)

    El-Masry, Amal A; Hammouda, Mohammed E A; El-Wasseef, Dalia R; El-Ashry, Saadia M

    2018-02-15

    Two simple, sensitive, rapid, validated and cost effective spectroscopic methods were established for quantification of antihistaminic drug azelastine (AZL) in bulk powder as well as in pharmaceutical dosage forms. In the first method (A) the absorbance difference between acidic and basic solutions was measured at 228nm, whereas in the second investigated method (B) the binary complex formed between AZL and Eosin Y in acetate buffer solution (pH3) was measured at 550nm. Different criteria that have critical influence on the intensity of absorption were deeply studied and optimized so as to achieve the highest absorption. The proposed methods obeyed Beer ' s low in the concentration range of (2.0-20.0μg·mL -1 ) and (0.5-15.0μg·mL -1 ) with % recovery±S.D. of (99.84±0.87), (100.02±0.78) for methods (A) and (B), respectively. Furthermore, the proposed methods were easily applied for quality control of pharmaceutical preparations without any conflict with its co-formulated additives, and the analytical results were compatible with those obtained by the comparison one with no significant difference as insured by student's t-test and the variance ratio F-test. Validation of the proposed methods was performed according the ICH guidelines in terms of linearity, limit of quantification, limit of detection, accuracy, precision and specificity, where the analytical results were persuasive. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The forensic validity of visual analytics

    Science.gov (United States)

    Erbacher, Robert F.

    2008-01-01

    The wider use of visualization and visual analytics in wide ranging fields has led to the need for visual analytics capabilities to be legally admissible, especially when applied to digital forensics. This brings the need to consider legal implications when performing visual analytics, an issue not traditionally examined in visualization and visual analytics techniques and research. While digital data is generally admissible under the Federal Rules of Evidence [10][21], a comprehensive validation of the digital evidence is considered prudent. A comprehensive validation requires validation of the digital data under rules for authentication, hearsay, best evidence rule, and privilege. Additional issues with digital data arise when exploring digital data related to admissibility and the validity of what information was examined, to what extent, and whether the analysis process was sufficiently covered by a search warrant. For instance, a search warrant generally covers very narrow requirements as to what law enforcement is allowed to examine and acquire during an investigation. When searching a hard drive for child pornography, how admissible is evidence of an unrelated crime, i.e. drug dealing. This is further complicated by the concept of "in plain view". When performing an analysis of a hard drive what would be considered "in plain view" when analyzing a hard drive. The purpose of this paper is to discuss the issues of digital forensics and the related issues as they apply to visual analytics and identify how visual analytics techniques fit into the digital forensics analysis process, how visual analytics techniques can improve the legal admissibility of digital data, and identify what research is needed to further improve this process. The goal of this paper is to open up consideration of legal ramifications among the visualization community; the author is not a lawyer and the discussions are not meant to be inclusive of all differences in laws between states and

  15. Development and analytical validation of a screening method for simultaneous detection of five adulterants in raw milk using mid-infrared spectroscopy and PLS-DA.

    Science.gov (United States)

    Botelho, Bruno G; Reis, Nádia; Oliveira, Leandro S; Sena, Marcelo M

    2015-08-15

    This paper proposed a new screening method for the simultaneous detection of five common adulterants in raw cow milk by using attenuated total reflectance (ATR) mid infrared spectroscopy and multivariate supervised classification (partial least squares discrimination analysis - PLSDA). The method was able to detect the presence of the adulterants water, starch, sodium citrate, formaldehyde and sucrose in milk samples containing from one up to five of these analytes, in the range of 0.5-10% w/v. A multivariate qualitative validation was performed, estimating specific figures of merit, such as false positive and false negative rates, selectivity, specificity and efficiency rates, accordance and concordance. The proposed method does not need any sample pretreatment, requires a small amount of sample (30 μL), is fast and simple, being suitable for the control of raw milk in a dairy industry or for the quality inspection of commercialized milk. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Systematic Development and Validation of a Thin-Layer Densitometric Bioanalytical Method for Estimation of Mangiferin Employing Analytical Quality by Design (AQbD) Approach.

    Science.gov (United States)

    Khurana, Rajneet Kaur; Rao, Satish; Beg, Sarwar; Katare, O P; Singh, Bhupinder

    2016-01-01

    The present work aims at the systematic development of a simple, rapid and highly sensitive densitometry-based thin-layer chromatographic method for the quantification of mangiferin in bioanalytical samples. Initially, the quality target method profile was defined and critical analytical attributes (CAAs) earmarked, namely, retardation factor (Rf), peak height, capacity factor, theoretical plates and separation number. Face-centered cubic design was selected for optimization of volume loaded and plate dimensions as the critical method parameters selected from screening studies employing D-optimal and Plackett-Burman design studies, followed by evaluating their effect on the CAAs. The mobile phase containing a mixture of ethyl acetate : acetic acid : formic acid : water in a 7 : 1 : 1 : 1 (v/v/v/v) ratio was finally selected as the optimized solvent for apt chromatographic separation of mangiferin at 262 nm withRf 0.68 ± 0.02 and all other parameters within the acceptance limits. Method validation studies revealed high linearity in the concentration range of 50-800 ng/band for mangiferin. The developed method showed high accuracy, precision, ruggedness, robustness, specificity, sensitivity, selectivity and recovery. In a nutshell, the bioanalytical method for analysis of mangiferin in plasma revealed the presence of well-resolved peaks and high recovery of mangiferin. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Validation and application of an analytical method for determining pesticides in the gas phase of ambient air.

    Science.gov (United States)

    Dos Santos, Luciane G; Lourencetti, Carolina; Pinto, Alicio A; Pignati, Wanderlei A; Dores, Eliana F G C

    2011-01-01

    A method for determining atmospheric concentrations of eight pesticides applied to corn and soybean crops in Mato Grosso state, Brazil is presented. The method involved a XAD-2 resin cartridge coupled to a low volume air pump at 2 L min⁻¹ over 8 hours. Pesticides were recovered from the resin using sonication with n-hexane:ethyl acetate and determined by GC-MS. Good accuracy (76-128%) and precision (CV gas phase samples collected between December 2008 and June 2009. Atrazine and endosulfan were detected both in urban and rural areas indicating the importance of atmospheric dispersion of pesticides in tropical areas. The simple and efficient extraction method and sampling system employed was considered suitable for identifying pesticides in areas of intense agricultural production.

  18. Development and validation of a 48-target analytical method for high-throughput monitoring of genetically modified organisms.

    Science.gov (United States)

    Li, Xiaofei; Wu, Yuhua; Li, Jun; Li, Yunjing; Long, Likun; Li, Feiwu; Wu, Gang

    2015-01-05

    The rapid increase in the number of genetically modified (GM) varieties has led to a demand for high-throughput methods to detect genetically modified organisms (GMOs). We describe a new dynamic array-based high throughput method to simultaneously detect 48 targets in 48 samples on a Fludigm system. The test targets included species-specific genes, common screening elements, most of the Chinese-approved GM events, and several unapproved events. The 48 TaqMan assays successfully amplified products from both single-event samples and complex samples with a GMO DNA amount of 0.05 ng, and displayed high specificity. To improve the sensitivity of detection, a preamplification step for 48 pooled targets was added to enrich the amount of template before performing dynamic chip assays. This dynamic chip-based method allowed the synchronous high-throughput detection of multiple targets in multiple samples. Thus, it represents an efficient, qualitative method for GMO multi-detection.

  19. Development and Validation of A 48-Target Analytical Method for High-throughput Monitoring of Genetically Modified Organisms

    Science.gov (United States)

    Li, Xiaofei; Wu, Yuhua; Li, Jun; Li, Yunjing; Long, Likun; Li, Feiwu; Wu, Gang

    2015-01-01

    The rapid increase in the number of genetically modified (GM) varieties has led to a demand for high-throughput methods to detect genetically modified organisms (GMOs). We describe a new dynamic array-based high throughput method to simultaneously detect 48 targets in 48 samples on a Fludigm system. The test targets included species-specific genes, common screening elements, most of the Chinese-approved GM events, and several unapproved events. The 48 TaqMan assays successfully amplified products from both single-event samples and complex samples with a GMO DNA amount of 0.05 ng, and displayed high specificity. To improve the sensitivity of detection, a preamplification step for 48 pooled targets was added to enrich the amount of template before performing dynamic chip assays. This dynamic chip-based method allowed the synchronous high-throughput detection of multiple targets in multiple samples. Thus, it represents an efficient, qualitative method for GMO multi-detection. PMID:25556930

  20. Analytical Validation of Quantitative Real-Time PCR Methods for Quantification of Trypanosoma cruzi DNA in Blood Samples from Chagas Disease Patients.

    Science.gov (United States)

    Ramírez, Juan Carlos; Cura, Carolina Inés; da Cruz Moreira, Otacilio; Lages-Silva, Eliane; Juiz, Natalia; Velázquez, Elsa; Ramírez, Juan David; Alberti, Anahí; Pavia, Paula; Flores-Chávez, María Delmans; Muñoz-Calderón, Arturo; Pérez-Morales, Deyanira; Santalla, José; Marcos da Matta Guedes, Paulo; Peneau, Julie; Marcet, Paula; Padilla, Carlos; Cruz-Robles, David; Valencia, Edward; Crisante, Gladys Elena; Greif, Gonzalo; Zulantay, Inés; Costales, Jaime Alfredo; Alvarez-Martínez, Miriam; Martínez, Norma Edith; Villarroel, Rodrigo; Villarroel, Sandro; Sánchez, Zunilda; Bisio, Margarita; Parrado, Rudy; Maria da Cunha Galvão, Lúcia; Jácome da Câmara, Antonia Cláudia; Espinoza, Bertha; Alarcón de Noya, Belkisyole; Puerta, Concepción; Riarte, Adelina; Diosque, Patricio; Sosa-Estani, Sergio; Guhl, Felipe; Ribeiro, Isabela; Aznar, Christine; Britto, Constança; Yadón, Zaida Estela; Schijman, Alejandro G

    2015-09-01

    An international study was performed by 26 experienced PCR laboratories from 14 countries to assess the performance of duplex quantitative real-time PCR (qPCR) strategies on the basis of TaqMan probes for detection and quantification of parasitic loads in peripheral blood samples from Chagas disease patients. Two methods were studied: Satellite DNA (SatDNA) qPCR and kinetoplastid DNA (kDNA) qPCR. Both methods included an internal amplification control. Reportable range, analytical sensitivity, limits of detection and quantification, and precision were estimated according to international guidelines. In addition, inclusivity and exclusivity were estimated with DNA from stocks representing the different Trypanosoma cruzi discrete typing units and Trypanosoma rangeli and Leishmania spp. Both methods were challenged against 156 blood samples provided by the participant laboratories, including samples from acute and chronic patients with varied clinical findings, infected by oral route or vectorial transmission. kDNA qPCR showed better analytical sensitivity than SatDNA qPCR with limits of detection of 0.23 and 0.70 parasite equivalents/mL, respectively. Analyses of clinical samples revealed a high concordance in terms of sensitivity and parasitic loads determined by both SatDNA and kDNA qPCRs. This effort is a major step toward international validation of qPCR methods for the quantification of T. cruzi DNA in human blood samples, aiming to provide an accurate surrogate biomarker for diagnosis and treatment monitoring for patients with Chagas disease. Copyright © 2015 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  1. Analytical Validation of Quantitative Real-Time PCR Methods for Quantification of Trypanosoma cruzi DNA in Blood Samples from Chagas Disease Patients

    Science.gov (United States)

    Ramírez, Juan Carlos; Cura, Carolina Inés; Moreira, Otacilio da Cruz; Lages-Silva, Eliane; Juiz, Natalia; Velázquez, Elsa; Ramírez, Juan David; Alberti, Anahí; Pavia, Paula; Flores-Chávez, María Delmans; Muñoz-Calderón, Arturo; Pérez-Morales, Deyanira; Santalla, José; Guedes, Paulo Marcos da Matta; Peneau, Julie; Marcet, Paula; Padilla, Carlos; Cruz-Robles, David; Valencia, Edward; Crisante, Gladys Elena; Greif, Gonzalo; Zulantay, Inés; Costales, Jaime Alfredo; Alvarez-Martínez, Miriam; Martínez, Norma Edith; Villarroel, Rodrigo; Villarroel, Sandro; Sánchez, Zunilda; Bisio, Margarita; Parrado, Rudy; Galvão, Lúcia Maria da Cunha; da Câmara, Antonia Cláudia Jácome; Espinoza, Bertha; de Noya, Belkisyole Alarcón; Puerta, Concepción; Riarte, Adelina; Diosque, Patricio; Sosa-Estani, Sergio; Guhl, Felipe; Ribeiro, Isabela; Aznar, Christine; Britto, Constança; Yadón, Zaida Estela; Schijman, Alejandro G.

    2015-01-01

    An international study was performed by 26 experienced PCR laboratories from 14 countries to assess the performance of duplex quantitative real-time PCR (qPCR) strategies on the basis of TaqMan probes for detection and quantification of parasitic loads in peripheral blood samples from Chagas disease patients. Two methods were studied: Satellite DNA (SatDNA) qPCR and kinetoplastid DNA (kDNA) qPCR. Both methods included an internal amplification control. Reportable range, analytical sensitivity, limits of detection and quantification, and precision were estimated according to international guidelines. In addition, inclusivity and exclusivity were estimated with DNA from stocks representing the different Trypanosoma cruzi discrete typing units and Trypanosoma rangeli and Leishmania spp. Both methods were challenged against 156 blood samples provided by the participant laboratories, including samples from acute and chronic patients with varied clinical findings, infected by oral route or vectorial transmission. kDNA qPCR showed better analytical sensitivity than SatDNA qPCR with limits of detection of 0.23 and 0.70 parasite equivalents/mL, respectively. Analyses of clinical samples revealed a high concordance in terms of sensitivity and parasitic loads determined by both SatDNA and kDNA qPCRs. This effort is a major step toward international validation of qPCR methods for the quantification of T. cruzi DNA in human blood samples, aiming to provide an accurate surrogate biomarker for diagnosis and treatment monitoring for patients with Chagas disease. PMID:26320872

  2. Validation of an HPLC Analytical Method for Determination of Biogenic Amines in Agricultural Products and Monitoring of Biogenic Amines in Korean Fermented Agricultural Products.

    Science.gov (United States)

    Yoon, Hyeock; Park, Jung Hyuck; Choi, Ari; Hwang, Han-Joon; Mah, Jae-Hyung

    2015-09-01

    An HPLC analytical method was validated for the quantitative determination of biogenic amines in agricultural products. Four agricultural foods, including apple juice, Juk, corn oil and peanut butter, were selected as food matrices based on their water and fat contents (i.e., non-fatty liquid, non-fatty solid, fatty liquid and fatty solid, respectively). The precision, accuracy, recovery, limit of detection (LOD) and quantification (LOQ) were determined to test the validity of an HPLC procedure for the determination of biogenic amines, including tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine, in each matrix. The LODs and LOQs for the biogenic amines were within the range of 0.01~0.10 mg/kg and 0.02~0.31 mg/kg, respectively. The relative standard deviation (RSD) of intraday for biogenic amine concentrations ranged from 1.86 to 5.95%, whereas the RSD of interday ranged from 2.08 to 5.96%. Of the matrices spiked with biogenic amines, corn oil with tyramine and Juk with putrescine exhibited the least accuracy of 84.85% and recovery rate of 89.63%, respectively, at the lowest concentration (10 mg/kg). Therefore, the validation results fulfilled AOAC criteria and recommendations. Subsequently, the method was applied to the analysis of biogenic amines in fermented agricultural products for a total dietary survey in Korea. Although the results revealed that Korean traditional soy sauce and Doenjang contained relatively high levels of histamine, the amounts are of no concern if these fermented agricultural products serve as condiments.

  3. Optimisation and validation of analytical methods for the simultaneous extraction of antioxidants: application to the analysis of tomato sauces.

    Science.gov (United States)

    Motilva, Maria-José; Macià, Alba; Romero, Maria-Paz; Labrador, Agustín; Domínguez, Alba; Peiró, Lluís

    2014-11-15

    In the present study, simultaneous extraction of natural antioxidants (phenols and carotenoids) in complex matrices, such as tomato sauces, is presented. The tomato sauce antioxidant compounds studied were the phenolics hydroxytyrosol, from virgin olive oil, quercetin and its derivatives, from onions, and quercetin-rutinoside as well as the carotenoid, lycopene (cis and trans), from tomatoes. These antioxidant compounds were extracted simultaneously with n-hexane/acetone/ethanol (50/25/25, v/v/v). The phenolics were analysed by ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS), and lycopene (cis- and trans-forms) was analysed using high-performance liquid chromatography coupled to a diode array detector (HPLC-DAD). After studying the parameters of these methods, they were applied to the analysis of virgin olive oil, fresh onion, tomato concentrate and tomato powder, and commercial five tomato sauces. Subsequently, the results obtained in our laboratory were compared with those from the Gallina Blanca Star Group laboratory. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Validation of analytical method to calculate the concentration of conjugated monoclonal antibody; Validacao de metodo analitico para calculo de concentracao de anticorpo monoclonal conjugado

    Energy Technology Data Exchange (ETDEWEB)

    Alcarde, Lais F.; Massicano, Adriana V.F.; Oliveira, Ricardo S.; Araujo, Elaine B. de, E-mail: lais_alcarde@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    The objective of this study was to develop a quantitative analytical method using high performance liquid chromatography (HPLC) to determine the antibody concentration in conjunction with bifunctional chelator. Assays were performed using a high performance liquid chromatograph, and the following conditions were used: flow rate of 1 mL / min, 15 min run time, 0.2 M sodium phosphate buffer pH 7.0 as the mobile phase and column of molecular exclusion BioSep SEC S-3000 (300 x 7.8 mm, 5 μM - Phenomenex). The calibration curve was obtained with AcM diluted in 0.2 M sodium phosphate buffer pH 7.0 by serial dilution, yielding the concentrations: 400 μg/mL, 200 μg/mL, 100 μg/mL, 50 μg/mL, 25 μg/mL and 12.5 μg/mL. From the calibration curve calculated the equation of the line and with it the concentration of the immunoconjugate. To ensure the validity of the method accuracy and precision studies were conducted. The accuracy test consisted in the evaluation of 3 samples of known concentration, being this test performed with low concentrations (50 μg/mL), medium (100 μg/mL) and high (200 μg/mL). The precision test consisted of 3 consecutive measurements of one sample of known concentration, subject to the conditions set forth above for the other tests. The correlation coefficient of the standard curve was greater than 97%, the accuracy was satisfactory at low concentrations as well as accuracy. The method was validated by showing it for the accurate and precise determination of the concentration of the immunoconjugate. Furthermore, this assay was found to be extremely important, because using the correct mass of the protein, the radiochemical purity of the radioimmunoconjugate was above 95% in all studies.

  5. Validation and application of an analytical method for the determination of selected acidic pharmaceuticals and estrogenic hormones in wastewater and sludge.

    Science.gov (United States)

    Zhang, Mengtao; Mao, Qianhui; Feng, Jingwei; Yuan, Shoujun; Wang, Qiquan; Huang, Deying; Zhang, Jibiao

    2016-09-18

    This study was undertaken to develop an extraction method for seven acidic pharmaceuticals and five steroidal estrogens from wastewater, treated wastewater and sludge samples. The temperature and time of sample derivatization using N,O-bis(trimethylsilyl)trifluoroacetamide was optimized. Our results show that pretreatment combined with solid phase extraction (SPE) for wastewater samples (using an ENVI-C18 cartridge) and liquid-solid extraction combined with SPE (using an HLB cartridge) for sludge samples increased the analytical efficiency for acidic pharmaceuticals and estrogenic hormones using gas chromatography-mass spectrometry (GC-MS). The derivatization conditions were optimized at 40°C for 2 h. In addition, the derivatized samples were stable at ambient temperature. The new method was validated and applied to the analysis of real wastewater and discharged sludge samples from a local wastewater treatment plant. Except for 17α-ethinylestradiol, all acidic pharmaceuticals and estrogens were detected in the influent, effluent and discharged sludge samples. The concentrations of these compounds were particularly high in the discharged sludge samples.

  6. VALIDATION OF ANALYTICAL PROCEDURES: A COMPARISON OF ICH Vs PHARMACOPOEIA (USP) Vs FDA

    OpenAIRE

    Sharma Ajay; Sharma Rohit

    2012-01-01

    Method validation is the process used to confirm that the analytical procedure employed for a specific test is suitable for its intended use. Results from method validation can be used to judge the quality, reliability and consistency of analytical results; it is an integral part of any good analytical practice. When extended to analytical procedure, depending upon the application, it means that a method works reproducibly, when carried out by same or different persons, in same or different l...

  7. Validation of an analytical method for analysis of cannabinoids in hair by headspace solid-phase microextraction and gas chromatography-ion trap tandem mass spectrometry.

    Science.gov (United States)

    Emídio, Elissandro Soares; Prata, Vanessa de Menezes; Dórea, Haroldo Silveira

    2010-06-18

    The development of an analytical method for the determination of Delta(9)-tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabinol (CBN) in samples of human hair is described. Samples were subjected to a procedure based on the combination of headspace solid-phase microextraction (HS-SPME) with gas chromatography linked with mass spectrometry operating in tandem mode (GC-MS/MS). A 10 mg aliquot of sample was firstly decontaminated using petroleum ether, deionized water and dichloromethane (2 mL of each solvent), for 10 min under sonication, and then digested in alkaline solution (1 mol L(-1) NaOH). The method variables evaluated were pH, mass of hair, fiber type, extraction temperature, desorption time, ionic strength, pre-equilibrium time and extraction time. Parameters concerning operation of the tandem mode MS/MS were also assessed and optimized. Validation of the method demonstrated excellent linearity in the range 0.1-8.0 ng mg(-1), with regression coefficients better than 0.994. Precision was determined using two different concentrations (upper and lower limits of the linear range), and RSD values were between 6.6 and 16.4%. Absolute recoveries (measured in triplicate) were in the range 1.1-8.7%, and limits of detection and quantification were 0.007-0.031 ng mg(-1) and 0.012-0.062 ng mg(-1), respectively. The LOQ for THC (0.062 ng mg(-1)) was below the cut-off value (LOQ Toxicologie Analytique (SFTA). The optimized SPME method was applied in analysis of hair samples from Cannabis drug users, showing that CBN and CBD were present in all samples analyzed. 2010 Elsevier B.V. All rights reserved.

  8. Develop and validation of an analytic method for the histamine determination in fish, using chromatography liquidates of high efficiency in reverse phase with ultraviolet detection

    International Nuclear Information System (INIS)

    Valverde Chavarria, J. C.

    1997-01-01

    There were determined and optimized the reaction and conditions analysis, for the derivation of the histamine with the reagent of or-ftalaldehido (OPA), it was proven that it is possible to quantify the one derived formed at 333nm. The good conditions crhomatografics settled down for the determination of the histamine in fish by means of the analytic technique of chromatography it liquidates of high efficiency (HPLC) in reverse phase, using the derivatizacion in precolumn of the histamine with the reagent of OPA, with ultraviolet detection at 333nm. The conditions of the proposed methodology were optimized and the variables of analytic acting were validated, for the analytic quantification of the histamine in the mg g-1 environment. The applicability of the methodology was demonstrated in the histamine determination in samples of fresh fish [es

  9. Analytical Method Validation and Quality Control of a Seven-Herb Chinese Medicine Formulation Used for the Treatment of Irritable Bowel Syndrome with Constipation.

    Science.gov (United States)

    Bourchier, Suzannah J; Bensoussan, Alan; Lee, Samiuela; Pearson, Jarryd L; Khoo, Cheang S

    2016-03-24

    There is a need for increased QC of complex herbal medicine formulations to ensure product consistency, efficacy, and safety. This study reports an HPLC with photodiode array and electrospray ionization-tandem MS method for quantifying selected analytes in a seven-herb formulation. Fourteen analytes were selected for quantification based on the criteria available from the Herbal Chemical Marker Ranking System, which takes into account the bioavailability, reported bioactivity, and physiological action related to its intended use, as well as commercial availability of the standard. After optimizing the columns and chromatographic conditions, 13 of the 14 analytes were able to be determined in one run, with the remaining analyte analyzed on its own. The method was successfully applied to two different extracts of the formulation, demonstrating an application for the QC of a complex herbal mixture with respect to their chemical characteristics.

  10. Analytical methods under emergency conditions

    International Nuclear Information System (INIS)

    Sedlet, J.

    1983-01-01

    This lecture discusses methods for the radiochemical determination of internal contamination of the body under emergency conditions, here defined as a situation in which results on internal radioactive contamination are needed quickly. The purpose of speed is to determine the necessity for medical treatment to increase the natural elimination rate. Analytical methods discussed include whole-body counting, organ counting, wound monitoring, and excreta analysis. 12 references

  11. Antimycobacterial Activities of N-Substituted-Glycinyl 1H-1,2,3-Triazolyl Oxazolidinones and Analytical Method Development and Validation for a Representative Compound

    Directory of Open Access Journals (Sweden)

    Naser F. Al-Tannak

    2017-10-01

    Full Text Available Twelve N-substituted-glycinyl triazolyl oxazolidinone derivatives were screened for antimycobacterial activity against susceptible (Mycobacterium tuberculosis (Mtb H37Rv and resistant (isoniazid (INH-resistant Mtb (SRI 1369, rifampin (RMP-resistant Mtb (SRI 1367, and ofloxacin (OFX-resistant Mtb (SRI 4000 Mtb strains. Most of the compounds showed moderate to strong antimycobacterial activity against all strains tested, with minimum inhibitory concentration (MIC value ranges of 0.5–11.5, 0.056–11.6, 0.11–5.8, and 0.03–11.6 μM, and percent inhibition ranges of 41–79%, 51–72%, 50–75%, and 52–71% against Mtb H37Rv, INH-R, RMP-R, and OFX-R M. tuberculosis, respectively. The 3,5-dinitrobenzoyl and 5-nitrofuroyl derivatives demonstrated strong antimycobacterial activities with the N-(5-nitrofuroyl derivatives (PH-145 and PH-189 being the most potent, with MIC value range of 0.3–0.6 μM against all strains tested. Compounds were not bactericidal, but showed intracellular (macrophage antimycobacterial activity. A reliable validated analytical method was developed for a representative compound PH-189 using Waters Acquity ultra High-Performance Liquid Chromatography (UHPLC system with quaternary Solvent Manager (H-Class. A simple extraction method indicated that PH-189 was stable in human plasma after 90 min at 37 °C with more than 90% successfully recovered. Moreover, stress stability studies were performed and degradants were identified by using UHPLC-ESI-QToF under acidic, basic, and oxidative simulated conditions.

  12. Decision analytic methods in RODOS

    International Nuclear Information System (INIS)

    Borzenko, V.; French, S.

    1996-01-01

    In the event of a nuclear accident, RODOS seeks to provide decision support at all levels ranging from the largely descriptive to providing a detailed evaluation of the benefits and disadvantages of various countermeasure strategies and ranking them according to the societal preferences as perceived by the decision makers. To achieve this, it must draw upon several decision analytic methods and bring them together in a coherent manner so that the guidance offered to decision makers is consistent from one stage of an accident to the next. The methods used draw upon multi-attribute value and utility theories

  13. Assessment of simpler calibration models in the development and validation of a fast postmortem multi-analyte LC-QTOF quantitation method in whole blood with simultaneous screening capabilities using SWATH acquisition.

    Science.gov (United States)

    Elmiger, Marco P; Poetzsch, Michael; Steuer, Andrea E; Kraemer, Thomas

    2017-11-01

    In postmortem toxicology, fast methods can provide a triage to avoid unnecessary autopsies. Usually, this requires multiple qualitative and quantitative analytical methods. The aim of the present study was to develop a postmortem LC-QTOF method for simultaneous screening and quantitation using easy sample preparation and reduced alternative calibration models. Hence, a method for 24 highly relevant substances in forensic toxicology was fully validated using the following calibration models: one-point external, one-point internal via corresponding deuterated standards, multi-point external daily calibration, and multi-point external weekly calibration. Two hundred microliters of postmortem blood were spiked with internal deuterated standard mixture and extracted by acetonitrile protein precipitation. Analysis was performed on a Sciex 6600 QTOF instrument with ESI+ mode using data-independent acquisition (DIA) namely sequential window acquisition of all theoretical mass spectra (SWATH). Validation of the different calibration models included selectivity, autosampler stability, recovery, matrix effects, accuracy, and precision for 24 substances. In addition, corresponding deuterated analogs of 52 substances were included to the internal standard mix for semi-quantitative concentration assessment. The simple protein precipitation provided recoveries higher than 55 and 75% for all analytes at low and high concentrations, respectively. Accuracy and precision criteria (bias and imprecision ± 15 and ± 20% near the limit of quantitation) were fulfilled by the different calibration models for most analytes. The validated method was successfully applied to more than 100 authentic postmortem samples and 3 proficiency tests. Furthermore, the one-point internal calibration via corresponding deuterated standard proved to be a considerably time saving technique for 76 analytes. Graphical abstract One-point and multi-point calibration and the resulting beta

  14. Improvement of the decision efficiency of the accuracy profile by means of a desirability function for analytical methods validation. Application to a diacetyl-monoxime colorimetric assay used for the determination of urea in transdermal iontophoretic extracts.

    Science.gov (United States)

    Rozet, E; Wascotte, V; Lecouturier, N; Préat, V; Dewé, W; Boulanger, B; Hubert, Ph

    2007-05-22

    Validation of analytical methods is a widely used and regulated step for each analytical method. However, the classical approaches to demonstrate the ability to quantify of a method do not necessarily fulfill this objective. For this reason an innovative methodology was recently introduced by using the tolerance interval and accuracy profile, which guarantee that a pre-defined proportion of future measurements obtained with the method will be included within the acceptance limits. Accuracy profile is an effective decision tool to assess the validity of analytical methods. The methodology to build such a profile is detailed here. However, as for any visual tool it has a part of subjectivity. It was then necessary to make the decision process objective in order to quantify the degree of adequacy of an accuracy profile and to allow a thorough comparison between such profiles. To achieve this, we developed a global desirability index based on the three most important validation criteria: the trueness, the precision and the range. The global index allows the classification of the different accuracy profiles obtained according to their respective response functions. A diacetyl-monoxime colorimetric assay for the determination of urea in transdermal iontophoretic extracts was used to illustrate these improvements.

  15. Validating dialect comparison methods

    NARCIS (Netherlands)

    Nerbonne, J.; Kleiweg, P.; Gaul, W; Ritter, G

    2002-01-01

    The range of dialectometric methods suggests the need for validation work. We propose a gold standard, based on the consensual classification of a well-studied area. Fidelity to the gold standard is assessed via matrix overlap measures (Rand and Fowlkes/Mallows). Word-based techniques in which

  16. The validation of an analytical method for sulfentrazone residue determination in soil using liquid chromatography and a comparison of chromatographic sensitivity to millet as a bioindicator species.

    Science.gov (United States)

    de Oliveira, Marcelo Antonio; Pires, Fábio Ribeiro; Ferraço, Mariana; Belo, Alessandra Ferreira

    2014-07-28

    Commonly used herbicides, such as sulfentrazone, pose the risk of soil contamination due to their persistence, bioaccumulation and toxicity. Phytoremediation by green manure species has been tested using biomarkers, but analytical data are now required to confirm the extraction of sulfentrazone from soil. Thus, the present work was carried out to analyze sulfentrazone residues in soil based on liquid chromatography with a comparison of these values to the sensitivity of the bioindicator Pennisetum glaucum. The soil samples were obtained after cultivation of Crotalaria juncea and Canavalia ensiformis at four seeding densities and with three doses of sulfentrazone. The seedlings were collected into pots, at two different depths, after 75 days of phytoremediator sowing and then were used to determine the herbicide persistence in the soil. A bioassay with P. glaucum was carried out in the same pot. High-performance liquid chromatography (HPLC), using UV-diode array detection (HPLC/UV-DAD), was used to determine the herbicide residues. The HPLC determination was optimized and validated according to the parameters of precision, accuracy, linearity, limit of detection and quantification, robustness and specificity. The bioindicator P. glaucum was more sensitive to sulfentrazone than residue determination by HPLC. Changes in sulfentrazone concentration caused by green manure phytoremediation were accurately identified by the bioindicator. However, a true correlation between the size of the species and the analyte content was not identified.

  17. The Validation of an Analytical Method for Sulfentrazone Residue Determination in Soil Using Liquid Chromatography and a Comparison of Chromatographic Sensitivity to Millet as a Bioindicator Species

    Directory of Open Access Journals (Sweden)

    Marcelo Antonio de Oliveira

    2014-07-01

    Full Text Available Commonly used herbicides, such as sulfentrazone, pose the risk of soil contamination due to their persistence, bioaccumulation and toxicity. Phytoremediation by green manure species has been tested using biomarkers, but analytical data are now required to confirm the extraction of sulfentrazone from soil. Thus, the present work was carried out to analyze sulfentrazone residues in soil based on liquid chromatography with a comparison of these values to the sensitivity of the bioindicator Pennisetum glaucum. The soil samples were obtained after cultivation of Crotalaria juncea and Canavalia ensiformis at four seeding densities and with three doses of sulfentrazone. The seedlings were collected into pots, at two different depths, after 75 days of phytoremediator sowing and then were used to determine the herbicide persistence in the soil. A bioassay with P. glaucum was carried out in the same pot. High-performance liquid chromatography (HPLC, using UV-diode array detection (HPLC/UV-DAD, was used to determine the herbicide residues. The HPLC determination was optimized and validated according to the parameters of precision, accuracy, linearity, limit of detection and quantification, robustness and specificity. The bioindicator P. glaucum was more sensitive to sulfentrazone than residue determination by HPLC. Changes in sulfentrazone concentration caused by green manure phytoremediation were accurately identified by the bioindicator. However, a true correlation between the size of the species and the analyte content was not identified.

  18. Development and validation of an analytical method using High Performance Liquid Chromatography (HPLC to determine ethyl butylacetylaminopropionate in topical repellent formulations

    Directory of Open Access Journals (Sweden)

    Isadora Cabral Pinto

    2017-06-01

    Full Text Available ABSTRACT Diseases caused by insects are frequent in poor countries, leading to epidemic scenarios in urban areas; e.g., Dengue, Zika and Chikungunya. For this reason, the development of a safe and efficient topical formulation is essential. Ethyl butylacetylaminopropionate (EB is a mosquito repellent developed by Merck, which is used in products for adults, children and especially babies, due to its low allergenic potential. The aim of this work was to validate an analytical methodology to quantify EB in a new poloxamer-based formulation by high-performance liquid chromatography (HPLC. The quantification methodology was performed at 40 ºC using a Kromasil reverse-phase column (C18, with the dimensions of 250 x 4.6 mm. The mobile phase was acetonitrile:water (1:1 at a 1.0 mL/min flow-rate. The detector wavelength was set at 218 nm to detect EB. The methodology was considered validated since the results indicated linearity (R2>0.99, specificity, selectivity, precision and accuracy (active recovery between 98% and 102%. It also presented limits of detection and quantification of 0.255 µg/mL and 0.849 µg/mL, respectively. The present study demonstrated the EB vehiculated in poloxamer gel is promising as a new insect repellent formulation, since it could be quantified and quality control evaluated.

  19. Analytical methods used at model facility

    International Nuclear Information System (INIS)

    Wing, N.S.

    1984-01-01

    A description of analytical methods used at the model LEU Fuel Fabrication Facility is presented. The methods include gravimetric uranium analysis, isotopic analysis, fluorimetric analysis, and emission spectroscopy

  20. Analytical method development and validation for quantification of uranium in compounds of the nuclear fuel cycle by Fourier Transform Infrared (FTIR) Spectroscopy

    International Nuclear Information System (INIS)

    Pereira, Elaine

    2016-01-01

    This work presents a low cost, simple and new methodology for direct quantification of uranium in compounds of the nuclear fuel cycle, based on Fourier Transform Infrared (FTIR) spectroscopy using KBr pressed discs technique. Uranium in different matrices were used to development and validation: UO 2 (NO 3 )2.2TBP complex (TBP uranyl nitrate complex) in organic phase and uranyl nitrate (UO 2 (NO 3 ) 2 ) in aqueous phase. The parameters used in the validation process were: linearity, selectivity, accuracy, limits of detection (LD) and quantitation (LQ), precision (repeatability and intermediate precision) and robustness. The method for uranium in organic phase (UO 2 (NO 3 )2.2TBP complex in hexane/embedded in KBr) was linear (r = 0.9980) over the range of 0.20% 2.85% U/ KBr disc, LD 0.02% and LQ 0.03%, accurate (recoveries were over 101.0%), robust and precise (RSD < 1.6%). The method for uranium aqueous phase (UO 2 (NO 3 ) 2 /embedded in KBr) was linear (r = 0.9900) over the range of 0.14% 1.29% U/KBr disc, LD 0.01% and LQ 0.02%, accurate (recoveries were over 99.4%), robust and precise (RSD < 1.6%). Some process samples were analyzed in FTIR and compared with gravimetric and X-ray fluorescence (XRF) analyses showing similar results in all three methods. The statistical tests (t-Student and Fischer) showed that the techniques are equivalent. The validated method can be successfully employed for routine quality control analysis for nuclear compounds. (author)

  1. Maritime Analytics Prototype: Phase 3 Validation

    Science.gov (United States)

    2014-01-01

    on U perations C tion scraped erest. Subje sing the new observed du s included in iii al artier TR ember c; aritime Visu der Advance...Browse idation even d, RCMP, an the tasks an help analyst ser Jury tria enter (MSOC from the web cts were give apps. ring both th teraction (e.g al...Analytical reasoning techniques that let users obtain deep insights that directly support assessment, planning, and decision making;  Visual

  2. Valid, legally defensible data from your analytical laboratories

    International Nuclear Information System (INIS)

    Gay, D.D.; Allen, V.C.

    1989-01-01

    This paper discusses the definition of valid, legally defensible data. The authors describe the expectations of project managers and what should be gleaned from the laboratory in regard to analytical data

  3. Theoretically Guided Analytical Method Development and Validation for the Estimation of Rifampicin in a Mixture of Isoniazid and Pyrazinamide by UV Spectrophotometer

    Science.gov (United States)

    Khan, Mohammad F.; Rita, Shamima A.; Kayser, Md. Shahidulla; Islam, Md. Shariful; Asad, Sharmeen; Bin Rashid, Ridwan; Bari, Md. Abdul; Rahman, Muhammed M.; Al Aman, D. A. Anwar; Setu, Nurul I.; Banoo, Rebecca; Rashid, Mohammad A.

    2017-01-01

    A simple, rapid, economic, accurate, and precise method for the estimation of rifampicin in a mixture of isoniazid and pyrazinamide by UV spectrophotometeric technique (guided by the theoretical investigation of physicochemical properties) was developed and validated. Theoretical investigations revealed that isoniazid and pyrazinamide both were freely soluble in water and slightly soluble in ethyl acetate whereas rifampicin was practically insoluble in water but freely soluble in ethyl acetate. This indicates that ethyl acetate is an effective solvent for the extraction of rifampicin from a water mixture of isoniazid and pyrazinamide. Computational study indicated that pH range of 6.0–8.0 would favor the extraction of rifampicin. Rifampicin is separated from isoniazid and pyrazinamide at pH 7.4 ± 0.1 by extracting with ethyl acetate. The ethyl acetate was then analyzed at λmax of 344.0 nm. The developed method was validated for linearity, accuracy and precision according to ICH guidelines. The proposed method exhibited good linearity over the concentration range of 2.5–35.0 μg/mL. The intraday and inter-day precision in terms of % RSD ranged from 1.09 to 1.70% and 1.63 to 2.99%, respectively. The accuracy (in terms of recovery) of the method varied from of 96.7 ± 0.9 to 101.1 ± 0.4%. The LOD and LOQ were found to be 0.83 and 2.52 μg/mL, respectively. In addition, the developed method was successfully applied to determine rifampicin combination (isoniazid and pyrazinamide) brands available in Bangladesh. PMID:28503547

  4. Theoretically Guided Analytical Method Development and Validation for the Estimation of Rifampicin in a Mixture of Isoniazid and Pyrazinamide by UV Spectrophotometer.

    Science.gov (United States)

    Khan, Mohammad F; Rita, Shamima A; Kayser, Md Shahidulla; Islam, Md Shariful; Asad, Sharmeen; Bin Rashid, Ridwan; Bari, Md Abdul; Rahman, Muhammed M; Al Aman, D A Anwar; Setu, Nurul I; Banoo, Rebecca; Rashid, Mohammad A

    2017-01-01

    A simple, rapid, economic, accurate, and precise method for the estimation of rifampicin in a mixture of isoniazid and pyrazinamide by UV spectrophotometeric technique (guided by the theoretical investigation of physicochemical properties) was developed and validated. Theoretical investigations revealed that isoniazid and pyrazinamide both were freely soluble in water and slightly soluble in ethyl acetate whereas rifampicin was practically insoluble in water but freely soluble in ethyl acetate. This indicates that ethyl acetate is an effective solvent for the extraction of rifampicin from a water mixture of isoniazid and pyrazinamide. Computational study indicated that pH range of 6.0-8.0 would favor the extraction of rifampicin. Rifampicin is separated from isoniazid and pyrazinamide at pH 7.4 ± 0.1 by extracting with ethyl acetate. The ethyl acetate was then analyzed at λ max of 344.0 nm. The developed method was validated for linearity, accuracy and precision according to ICH guidelines. The proposed method exhibited good linearity over the concentration range of 2.5-35.0 μg/mL. The intraday and inter-day precision in terms of % RSD ranged from 1.09 to 1.70% and 1.63 to 2.99%, respectively. The accuracy (in terms of recovery) of the method varied from of 96.7 ± 0.9 to 101.1 ± 0.4%. The LOD and LOQ were found to be 0.83 and 2.52 μg/mL, respectively. In addition, the developed method was successfully applied to determine rifampicin combination (isoniazid and pyrazinamide) brands available in Bangladesh.

  5. Reactor Section standard analytical methods. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Sowden, D.

    1954-07-01

    the Standard Analytical Methods manual was prepared for the purpose of consolidating and standardizing all current analytical methods and procedures used in the Reactor Section for routine chemical analyses. All procedures are established in accordance with accepted practice and the general analytical methods specified by the Engineering Department. These procedures are specifically adapted to the requirements of the water treatment process and related operations. The methods included in this manual are organized alphabetically within the following five sections which correspond to the various phases of the analytical control program in which these analyses are to be used: water analyses, essential material analyses, cotton plug analyses boiler water analyses, and miscellaneous control analyses.

  6. Implementation of QbD Approach to the Analytical Method Development and Validation for the Estimation of Propafenone Hydrochloride in Tablet Dosage Form

    Directory of Open Access Journals (Sweden)

    Monika L. Jadhav

    2013-01-01

    Full Text Available Chromatographic and spectrophotometric methods were developed according to Quality by Design (QbD approach as per ICH Q8(R2 guidelines for estimation of propafenone hydrochloride in tablet dosage form. QbD approach was carried out by varying various parameters and these variable parameters were designed into Ishikawa diagram. The critical parameters were determined by using principal component analysis as well as by observation. Estimated critical parameters in HPTLC method include solvent methanol, mode of detection absorbance, precoated aluminium backed TLC plate (10 cm 10 cm, wavelength: 250 nm, saturation time: 20 min, band length: 8 mm, solvent front: 70 mm, volume of mobile phase: 5 mL, type of chamber: 10 cm 10 cm, scanning time: 10 min, and mobile phase methanol : ethyl acetate : triethylamine (1.5 : 3.5 : 0.4 v/v/v. Estimated critical parameters in zero order spectrophotometric method were solvent methanol, sample preparation tablet, wavelength: 247.4 nm, slit width: 1.0, scan speed medium, and sampling interval: 0.2, and for first order derivative spectrophotometric method it was scaling factor: 5 and delta lambda 4. The above methods were validated according to ICH Q2(R1 guidelines. Proposed methods can be used for routine analysis of propafenone hydrochloride in tablet dosage form as they were found to be robust and specific.

  7. Determination of Anthracycline Drug Residual in Cleaning Validation Swabs of Stainless-Steel Equipment after Production of Cytostatic Injections Using HPLC Analytical Method

    Directory of Open Access Journals (Sweden)

    Zuzana Slivová

    2015-01-01

    Full Text Available Standard cleaning procedures of production line equipment were verified after manufacture of cytostatic injections containing Anthracycline derivate substance. Residual content of Anthracycline drug substance on stainless-steel equipment surface was determined using swab sampling with a specific HPLC-DAD analysis. The acceptance limit was decided as 200.0 μg/100 cm2. Recovery from the stainless-steel surface was 90.1%. Linearity of the method was observed in the concentration range of 0.155–194 μg/mL when estimated using Zorbax TMS (5 μm, 0.25 m × 4.6 mm ID column at 1.3 mL/min flow rate and 254 nm (DAD 190–600 nm. The mobile phase consisted of lauryl hydrogen sulphate solution (3.7 g/L : methanol : acetonitrile (54 : 16 : 30, v/v/v with pH adjusted to 2.5 using phosphoric acid (85%. The LOD and LOQ for Anthracycline derivate were found to be 0.047 and 0.155 μg/mL, respectively. The method validation confirmed the method provides acceptable degree of selectivity, linearity, accuracy, and precision for the intended purposes.

  8. Development and validation of new analytical methods for simultaneous estimation of Drotaverine hydrochloride in combination with Omeprazole in a pharmaceutical dosage form

    Directory of Open Access Journals (Sweden)

    Smita Sharma

    2017-02-01

    Full Text Available A rapid and precise method (in accordance with ICH guidelines is developed for the quantitative simultaneous determination of Drotaverine hydrochloride and Omeprazole in a combined pharmaceutical dosage form. Three methods are described for the simultaneous determination of Drotaverine hydrochloride and Omeprazole in a binary mixture. The first method was based on UV-Spectrophotometric determination of two drugs, using Vierordt!s simultaneous equation method. It involves absorbance measurement at 226.8 nm (λmax of Drotaverine hydrochloride and 269.4 nm (λmax of Omeprazole in methanol; linearity was obtained in the range of 5–30 μg ml−1 for both the drugs. The second method was based on HPLC separation of the two drugs using potassium dihydrogen phosphate buffer pH 5.0: Acetonitrile: Triethylamine (60:40:0.5, v/v as a mobile phase. Areas were recorded at 260 nm for both the drugs and retention time was found to be 2.71 min. and 3.87 min for Drotaverine hydrochloride and Omeprazole, respectively at 1.0 mL/min flow rate. The selected chromatographic conditions were found to determine Drotaverine hydrochloride and Omeprazole quantitatively in a combined dosage form without any physical separation. The method has been validated for linearity, accuracy and precision. Linearity was found over the range of 5–30 μg mL−1 for both drugs. The third method was based on HPTLC method for simultaneous quantification of these compounds in pharmaceutical dosage forms. Precoated silica gel 60 F254 plate was used as stationary phase. The separation was carried out using Glacial acetic acid:Cyclohexane:Methanol:(80:15:5 v/v/v as mobile phase. The proposed method was found to be fast, accurate, precise, reproducible and rugged and can be used for a simultaneous analysis of these drugs in combined formulations.

  9. HTGR analytical methods and design verification

    International Nuclear Information System (INIS)

    Neylan, A.J.; Northup, T.E.

    1982-05-01

    Analytical methods for the high-temperature gas-cooled reactor (HTGR) include development, update, verification, documentation, and maintenance of all computer codes for HTGR design and analysis. This paper presents selected nuclear, structural mechanics, seismic, and systems analytical methods related to the HTGR core. This paper also reviews design verification tests in the reactor core, reactor internals, steam generator, and thermal barrier

  10. Synthesis of trans- and cis-4'-hydroxylomustine and development of validated analytical method for lomustine and trans- and cis-4'-hydroxylomustine in canine plasma.

    Science.gov (United States)

    Dirikolu, L; Chakkath, T; Fan, T; Mente, Nolan R

    2009-01-01

    In veterinary medicine, lomustine has been successfull used primarily for the treatment of resistant lymphoma and also for the treatment of mast cell tumors, intracranial meningioma, epitheliotropic lymphoma, and histiocytic sarcoma in dogs either alone or in combination with other chemotherapeutic agents. Even though lomustine is commonly used in dogs primarily for the treatment of resistant lymphoma, there is no pharmacokinetics information available regarding this compound in dogs. In the present study, we developed and validated a simple high-performance liquid chromatography (HPLC) method with a one-step liquid-liquid extraction procedure to detect and quantify lomustine and its two monohydroxylated metabolites (trans- and cis-4'-hydroxylomustine) in canine plasma for future pharmacokinetic studies. The HPLC-diode-array detection method reported here readily detects lomustine, cis-4'-hydroxylomustine, and trans-4'-hydroxylomustine in canine plasma with a limit of detection of lomustine, cis-4'-hydroxylomustine, and trans-4'-hydroxylomustine in plasma of about 10 ng/120 microL, 5 ng/120 microL, and 5 ng/120 microL, respectively. The mean extraction efficiency values for lomustine, cis-4'-hydroxylomustine, and trans-4'-hydroxylomustine were 73%, 90%, and 89%, respectively, from canine plasma samples on HPLC. The present study also provides stability information about lomustine and its two monohydroxylated metabolites in canine plasma and methanol solution stored at various conditions.

  11. Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS)

    International Nuclear Information System (INIS)

    Guilhen, Sabine Neusatz

    2009-01-01

    Mercury (Hg) is a toxic metal applied to a variety of products and processes, representing a risk to the health of occupationally or accidentally exposed subjects. Dental amalgam is a restorative material composed of metallic mercury, which use has been widely debated in the last decades. Due to the dubiety of the studies concerning dental amalgam, many efforts concerning this issue have been conducted. The Tropical Medicine Foundation (Tocantins, Brazil) has recently initiated a study to evaluate the environmental and occupational levels of exposure to mercury in dentistry attendants at public consulting rooms in the city of Araguaina (TO). In collaboration with this study, the laboratory of analysis at IPEN's Chemistry and Environment Center is undertaking the analysis of mercury levels in exposed subjects' urine samples using cold vapor atomic absorption spectrometry. This analysis requires the definition of a methodology capable of generating reliable results. Such methodology can only be implemented after a rigorous validation procedure. As part of this work, a series of tests were conducted in order to confirm the suitability of the selected methodology and to assert that the laboratory addresses all requirements needed for a successful implementation of the methodology. The following parameters were considered in order to test the method's performance: detection and quantitation limits, selectivity, sensitivity, linearity, accuracy and precision. The assays were carried out with certified reference material, which assures the traceability of the results. Taking into account the estimated parameters, the method can be considered suitable for the afore mentioned purpose. The mercury concentration found for the reference material was of (95,12 +- 11,70)mug.L -1 with a recovery rate of 97%. The method was also applied to 39 urine samples, six of which (15%) showing urinary mercury levels above the normal limit of 10μg.L -1 . The obtained results fall into a

  12. Analytical method development and validation of simultaneous estimation of rabeprazole, pantoprazole, and itopride by reverse-phase high-performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Senthamil Selvan Perumal

    2014-12-01

    Full Text Available A simple, selective, rapid, and precise reverse-phase high-performance liquid chromatography (RP-HPLC method for the simultaneous estimation of rabeprazole (RP, pantoprazole (PP, and itopride (IP has been developed. The compounds were well separated on a Phenomenex C18 (Luna column (250 mm × 4.6 mm, dp = 5 μm with C18 guard column (4 mm × 3 mm × 5 μm with a mobile phase consisting of buffer containing 10 mM potassium dihydrogen orthophosphate (adjusted to pH 6.8: acetonitrile (70:30 v/v at a flow rate of 1.0 mL/min and ultraviolet detection at 288 nm. The retention time of RP, PP, and IP were 5.35, 7.92, and 11.16 minutes, respectively. Validation of the proposed method was carried out according to International Conference on Harmonisation (ICH guidelines. Linearity range was obtained for RP, PP, and IP over the concentration range of 2.5–25, 1–30, and 3–35 μg/mL and the r2 values were 0.994, 0.978, and 0.991, respectively. The calculated limit of detection (LOD values were 1, 0.3, and 1 μg/mL and limit of quantitation (LOQ values were 2.5, 1, and 3 μg/mL for RP, PP, and IP correspondingly. Thus, the current study showed that the developed reverse-phase liquid chromatography method is sensitive and selective for the estimation of RP, PP, and IP in combined dosage form.

  13. Validation Process Methods

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, John E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); English, Christine M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gesick, Joshua C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mukkamala, Saikrishna [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2018-01-04

    This report documents the validation process as applied to projects awarded through Funding Opportunity Announcements (FOAs) within the U.S. Department of Energy Bioenergy Technologies Office (DOE-BETO). It describes the procedures used to protect and verify project data, as well as the systematic framework used to evaluate and track performance metrics throughout the life of the project. This report also describes the procedures used to validate the proposed process design, cost data, analysis methodologies, and supporting documentation provided by the recipients.

  14. Validation of an analytical method based on the high-resolution continuum source flame atomic absorption spectrometry for the fast-sequential determination of several hazardous/priority hazardous metals in soil.

    Science.gov (United States)

    Frentiu, Tiberiu; Ponta, Michaela; Hategan, Raluca

    2013-03-01

    The aim of this paper was the validation of a new analytical method based on the high-resolution continuum source flame atomic absorption spectrometry for the fast-sequential determination of several hazardous/priority hazardous metals (Ag, Cd, Co, Cr, Cu, Ni, Pb and Zn) in soil after microwave assisted digestion in aqua regia. Determinations were performed on the ContrAA 300 (Analytik Jena) air-acetylene flame spectrometer equipped with xenon short-arc lamp as a continuum radiation source for all elements, double monochromator consisting of a prism pre-monocromator and an echelle grating monochromator, and charge coupled device as detector. For validation a method-performance study was conducted involving the establishment of the analytical performance of the new method (limits of detection and quantification, precision and accuracy). Moreover, the Bland and Altman statistical method was used in analyzing the agreement between the proposed assay and inductively coupled plasma optical emission spectrometry as standardized method for the multielemental determination in soil. The limits of detection in soil sample (3σ criterion) in the high-resolution continuum source flame atomic absorption spectrometry method were (mg/kg): 0.18 (Ag), 0.14 (Cd), 0.36 (Co), 0.25 (Cr), 0.09 (Cu), 1.0 (Ni), 1.4 (Pb) and 0.18 (Zn), close to those in inductively coupled plasma optical emission spectrometry: 0.12 (Ag), 0.05 (Cd), 0.15 (Co), 1.4 (Cr), 0.15 (Cu), 2.5 (Ni), 2.5 (Pb) and 0.04 (Zn). Accuracy was checked by analyzing 4 certified reference materials and a good agreement for 95% confidence interval was found in both methods, with recoveries in the range of 94-106% in atomic absorption and 97-103% in optical emission. Repeatability found by analyzing real soil samples was in the range 1.6-5.2% in atomic absorption, similar with that of 1.9-6.1% in optical emission spectrometry. The Bland and Altman method showed no statistical significant difference between the two spectrometric

  15. Analytical methods of radwaste characterization

    International Nuclear Information System (INIS)

    Garcia, C.M.

    1994-10-01

    In view of the need to carry out more extensive studies on the design of newly proposed methods for the treatment of radioactive wastes collected at PNRI, this study is aimed to provide a guide in the characterization of wastes which is a preparatory step for a well-planned waste processing. (auth.). 8 refs

  16. 7 CFR 91.23 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ...-2417. (i) Standard Analytical Methods of the Member Companies of Corn Industries Research Foundation... Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) COMMODITY LABORATORY TESTING PROGRAMS...

  17. A New Method to Study Analytic Inequalities

    Directory of Open Access Journals (Sweden)

    Xiao-Ming Zhang

    2010-01-01

    Full Text Available We present a new method to study analytic inequalities involving n variables. Regarding its applications, we proved some well-known inequalities and improved Carleman's inequality.

  18. Validating Analytical Protocols to Determine Selected Pesticides and PCBs Using Routine Samples

    Directory of Open Access Journals (Sweden)

    Oscar Pindado Jiménez

    2017-01-01

    Full Text Available This study aims at providing recommendations concerning the validation of analytical protocols by using routine samples. It is intended to provide a case-study on how to validate the analytical methods in different environmental matrices. In order to analyze the selected compounds (pesticides and polychlorinated biphenyls in two different environmental matrices, the current work has performed and validated two analytical procedures by GC-MS. A description is given of the validation of the two protocols by the analysis of more than 30 samples of water and sediments collected along nine months. The present work also scopes the uncertainty associated with both analytical protocols. In detail, uncertainty of water sample was performed through a conventional approach. However, for the sediments matrices, the estimation of proportional/constant bias is also included due to its inhomogeneity. Results for the sediment matrix are reliable, showing a range 25–35% of analytical variability associated with intermediate conditions. The analytical methodology for the water matrix determines the selected compounds with acceptable recoveries and the combined uncertainty ranges between 20 and 30%. Analyzing routine samples is rarely applied to assess trueness of novel analytical methods and up to now this methodology was not focused on organochlorine compounds in environmental matrices.

  19. Validation of a multi-analyte HPLC-DAD method for determination of uric acid, creatinine, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid and 2-methylhippuric acid in human urine.

    Science.gov (United States)

    Remane, Daniela; Grunwald, Soeren; Hoeke, Henrike; Mueller, Andrea; Roeder, Stefan; von Bergen, Martin; Wissenbach, Dirk K

    2015-08-15

    During the last decades exposure sciences and epidemiological studies attracts more attention to unravel the mechanisms for the development of chronic diseases. According to this an existing HPLC-DAD method for determination of creatinine in urine samples was expended for seven analytes and validated. Creatinine, uric acid, homovanillic acid, niacinamide, hippuric acid, indole-3-acetic acid, and 2-methylhippuric acid were separated by gradient elution (formate buffer/methanol) using an Eclipse Plus C18 Rapid Resolution column (4.6mm×100mm). No interfering signals were detected in mobile phase. After injection of blank urine samples signals for the endogenous compounds but no interferences were detected. All analytes were linear in the selected calibration range and a non weighted calibration model was chosen. Bias, intra-day and inter-day precision for all analytes were below 20% for quality control (QC) low and below 10% for QC medium and high. The limits of quantification in mobile phase were in line with reported reference values but had to be adjusted in urine for homovanillic acid (45mg/L), niacinamide 58.5(mg/L), and indole-3-acetic acid (63mg/L). Comparison of creatinine data obtained by the existing method with those of the developed method showing differences from -120mg/L to +110mg/L with a mean of differences of 29.0mg/L for 50 authentic urine samples. Analyzing 50 authentic urine samples, uric acid, creatinine, hippuric acid, and 2-methylhippuric acid were detected in (nearly) all samples. However, homovanillic acid was detected in 40%, niacinamide in 4% and indole-3-acetic acid was never detected within the selected samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Development and validation of a new analytical method for the determination of 1,4-dichlorobenzene in honey by gas chromatography-isotope dilution mass spectrometry after steam-distillation.

    Science.gov (United States)

    Botitsi, E V; Kormali, P N; Kontou, S N; Economou, A; Tsipi, D F

    2006-10-02

    A simple, fast, sensitive and robust analytical method using gas chromatography (GC)-isotope dilution mass spectrometry (MS) was developed and validated for the identification and quantification of 1,4-dichlorobenzene (p-DCB) residues in honey samples. The proposed methodology is based on steam-distillation using a Clevenger-type apparatus followed by gas chromatography-mass spectrometry (GC-MS) in the selected ion monitoring (SIM) mode employing the isotopically labeled analogue d4-1,4-dichlorobenzene (d4-p-DCB) as internal standard (IS). Validation of the method was performed in two different GC-MS systems, using quadrupole MS (QMS) and ion-trap MS (ITMS) detectors, with no statistically significant differences between two. Recoveries were better than 91% with percent relative standard deviations lower than 12%. The instrumental limits of detection were 1 microg kg(-1) in the GC-ITMS system and 0.6 microg kg(-1) in the GC-QMS system. The expanded uncertainty was estimated as 17% at the currently accepted "action level" of 10 microg kg(-1). The method was applied to the analysis of 310 honey samples in an extensive national monitoring study. A quality control (QC) system applied during the assays has demonstrated a good performance and long-term stability over a period of more than 8 months of continuous operation.

  1. Analytical and computational methods in electromagnetics

    CERN Document Server

    Garg, Ramesh

    2008-01-01

    This authoritative resource offers you clear and complete explanation of this essential electromagnetics knowledge, providing you with the analytical background you need to understand such key approaches as MoM (method of moments), FDTD (Finite Difference Time Domain) and FEM (Finite Element Method), and Green's functions. This comprehensive book includes all math necessary to master the material.

  2. Mathematical methods for physical and analytical chemistry

    CERN Document Server

    Goodson, David Z

    2011-01-01

    Mathematical Methods for Physical and Analytical Chemistry presents mathematical and statistical methods to students of chemistry at the intermediate, post-calculus level. The content includes a review of general calculus; a review of numerical techniques often omitted from calculus courses, such as cubic splines and Newton's method; a detailed treatment of statistical methods for experimental data analysis; complex numbers; extrapolation; linear algebra; and differential equations. With numerous example problems and helpful anecdotes, this text gives chemistry students the mathematical

  3. Study of hydroxymethylfurfural and furfural formation in cakes during baking in different ovens, using a validated multiple-stage extraction-based analytical method.

    Science.gov (United States)

    Petisca, Catarina; Henriques, Ana Rita; Pérez-Palacios, Trinidad; Pinho, Olívia; Ferreira, Isabel M P L V O

    2013-12-15

    A procedure for extraction of hydroxymethylfurfural (HMF) and furfural from cakes was validated. Higher yield was achieved by multiple step extraction with water/methanol (70/30) and clarification with Carrez I and II reagents. Oven type and baking time strongly influenced HMF, moisture and volatile profile of model cakes, whereas furfural content was not significantly affected. No correlation was found between these parameters. Baking time influenced moisture and HMF formation in cakes from traditional and microwave ovens but not in steam oven cakes. Significant moisture decrease and HMF increase (3.63, 9.32, and 41.9 mg kg(-1)dw at 20, 40 and 60 min, respectively) were observed during traditional baking. Cakes baked by microwave also presented a significant increase of HMF (up to 16.84 mg kg(-1)dw at 2.5 min). Steam oven cakes possessed the highest moisture content and no significant differences in HMF and furfural. This oven is likely to form low HMF and furfural, maintaining cake moisture and aroma compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Risk analysis of analytical validations by probabilistic modification of FMEA

    DEFF Research Database (Denmark)

    Barends, D.M.; Oldenhof, M.T.; Vredenbregt, M.J.

    2012-01-01

    Risk analysis is a valuable addition to validation of an analytical chemistry process, enabling not only detecting technical risks, but also risks related to human failures. Failure Mode and Effect Analysis (FMEA) can be applied, using a categorical risk scoring of the occurrence, detection...... of severity. In an example, the results of traditional FMEA of a Near Infrared (NIR) analytical procedure used for the screening of suspected counterfeited tablets are re-interpretated by this probabilistic modification of FMEA. Using this probabilistic modification of FMEA, the frequency of occurrence...... of undetected failure mode(s) can be estimated quantitatively, for each individual failure mode, for a set of failure modes, and the full analytical procedure....

  5. 7 CFR 93.13 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... PROCESSED FRUITS AND VEGETABLES Peanuts, Tree Nuts, Corn and Other Oilseeds § 93.13 Analytical methods. Official analyses for peanuts, nuts, corn, oilseeds, and related vegetable oils are found in the following..., Englewood Cliffs, New Jersey 07632. (c) Analyst's Instruction for Aflatoxin (August 1994), S&T Instruction...

  6. Biodiesel Analytical Methods: August 2002--January 2004

    Energy Technology Data Exchange (ETDEWEB)

    Van Gerpen, J.; Shanks, B.; Pruszko, R.; Clements, D.; Knothe, G.

    2004-07-01

    Biodiesel is an alternative fuel for diesel engines that is receiving great attention worldwide. The material contained in this book is intended to provide the reader with information about biodiesel engines and fuels, analytical methods used to measure fuel properties, and specifications for biodiesel quality control.

  7. Analytic methods to generate integrable mappings

    Indian Academy of Sciences (India)

    2015-10-22

    Oct 22, 2015 ... Systematic analytic methods of deriving integrable mappings from integrable nonlinear ordinary differential, differential-difference and lattice equations are presented. More specifically, we explain how to derive integrable mappings through four different techniques namely,. dis-cretization technique,; Lax ...

  8. Numerical and analytical methods with Matlab

    CERN Document Server

    Bober, William; Masory, Oren

    2013-01-01

    Numerical and Analytical Methods with MATLAB® presents extensive coverage of the MATLAB programming language for engineers. It demonstrates how the built-in functions of MATLAB can be used to solve systems of linear equations, ODEs, roots of transcendental equations, statistical problems, optimization problems, control systems problems, and stress analysis problems. These built-in functions are essentially black boxes to students. By combining MATLAB with basic numerical and analytical techniques, the mystery of what these black boxes might contain is somewhat alleviated. This classroom-tested

  9. Prioritizing pesticide compounds for analytical methods development

    Science.gov (United States)

    Norman, Julia E.; Kuivila, Kathryn; Nowell, Lisa H.

    2012-01-01

    The U.S. Geological Survey (USGS) has a periodic need to re-evaluate pesticide compounds in terms of priorities for inclusion in monitoring and studies and, thus, must also assess the current analytical capabilities for pesticide detection. To meet this need, a strategy has been developed to prioritize pesticides and degradates for analytical methods development. Screening procedures were developed to separately prioritize pesticide compounds in water and sediment. The procedures evaluate pesticide compounds in existing USGS analytical methods for water and sediment and compounds for which recent agricultural-use information was available. Measured occurrence (detection frequency and concentrations) in water and sediment, predicted concentrations in water and predicted likelihood of occurrence in sediment, potential toxicity to aquatic life or humans, and priorities of other agencies or organizations, regulatory or otherwise, were considered. Several existing strategies for prioritizing chemicals for various purposes were reviewed, including those that identify and prioritize persistent, bioaccumulative, and toxic compounds, and those that determine candidates for future regulation of drinking-water contaminants. The systematic procedures developed and used in this study rely on concepts common to many previously established strategies. The evaluation of pesticide compounds resulted in the classification of compounds into three groups: Tier 1 for high priority compounds, Tier 2 for moderate priority compounds, and Tier 3 for low priority compounds. For water, a total of 247 pesticide compounds were classified as Tier 1 and, thus, are high priority for inclusion in analytical methods for monitoring and studies. Of these, about three-quarters are included in some USGS analytical method; however, many of these compounds are included on research methods that are expensive and for which there are few data on environmental samples. The remaining quarter of Tier 1

  10. Analytical detection methods for irradiated foods

    International Nuclear Information System (INIS)

    1991-03-01

    The present publication is a review of scientific literature on the analytical identification of foods treated with ionizing radiation and the quantitative determination of absorbed dose of radiation. Because of the extremely low level of chemical changes resulting from irradiation or because of the lack of specificity to irradiation of any chemical changes, a few methods of quantitative determination of absorbed dose have shown promise until now. On the other hand, the present review has identified several possible methods, which could be used, following further research and testing, for the identification of irradiated foods. An IAEA Co-ordinated Research Programme on Analytical Detection Methods for Irradiation Treatment of Food ('ADMIT'), established in 1990, is currently investigating many of the methods cited in the present document. Refs and tab

  11. Workshop on Analytical Methods in Statistics

    CERN Document Server

    Jurečková, Jana; Maciak, Matúš; Pešta, Michal

    2017-01-01

    This volume collects authoritative contributions on analytical methods and mathematical statistics. The methods presented include resampling techniques; the minimization of divergence; estimation theory and regression, eventually under shape or other constraints or long memory; and iterative approximations when the optimal solution is difficult to achieve. It also investigates probability distributions with respect to their stability, heavy-tailness, Fisher information and other aspects, both asymptotically and non-asymptotically. The book not only presents the latest mathematical and statistical methods and their extensions, but also offers solutions to real-world problems including option pricing. The selected, peer-reviewed contributions were originally presented at the workshop on Analytical Methods in Statistics, AMISTAT 2015, held in Prague, Czech Republic, November 10-13, 2015.

  12. Desarrollo y validación de los métodos analíticos para el control de calidad del micocilén polvo Development and validation of analytical methods for quality control of Micocilen powder

    Directory of Open Access Journals (Sweden)

    Yania Suárez Pérez

    2011-06-01

    Full Text Available El micocilén es un medicamento que se presenta en forma de polvo. Contiene 2 ingredientes farmacéuticos activos: el ácido undecilénico y el undecilinato de zinc. Por su acción fungistática, se ha convertido en un producto de alta demanda en Cuba, ya que las micosis se favorecen en climas cálidos y húmedos. Se realizó el desarrollo y la validación de 2 métodos analíticos para el control de calidad sobre la base de la cuantificación de cada analito presente en la formulación. Se seleccionaron técnicas volumétricas por neutralización acuosa y complejometría. Los resultados fueron satisfactorios, ya que en ambos casos se obtuvo adecuada especificidad, linealidad, exactitud, precisión y robustez. Los métodos propuestos se compararon con los aplicados anteriormente y se obtuvieron resultados mucho más confiables, según resultados del análisis estadístico aplicado, sin diferencias significativas entre las réplicas de un mismo lote.The undecylenic acid (Micocilen is a drug in powder presentation containing two active pharmaceutical ingredients: undecylenic acid and zinc undecylenate. By its fungistatic action becames a first line product in Cuba because of mycoses are typical of wet and warm climates. Development and validation of two analytical methods for the quality control on the base of the quantification of each symbol present in the formula. Volumetric techniques were selected by aqueous neutralization and complexometric. Results were satisfactory since in both cases an appropriate specificity, linearity, accuracy, precision and robustness were obtained. Methods proposed were compared to those previously applied obtaining more reliable results, according to results of analytical analysis applied, without significant differences among replica of a same batch.

  13. Development of quality-by-design analytical methods.

    Science.gov (United States)

    Vogt, Frederick G; Kord, Alireza S

    2011-03-01

    Quality-by-design (QbD) is a systematic approach to drug development, which begins with predefined objectives, and uses science and risk management approaches to gain product and process understanding and ultimately process control. The concept of QbD can be extended to analytical methods. QbD mandates the definition of a goal for the method, and emphasizes thorough evaluation and scouting of alternative methods in a systematic way to obtain optimal method performance. Candidate methods are then carefully assessed in a structured manner for risks, and are challenged to determine if robustness and ruggedness criteria are satisfied. As a result of these studies, the method performance can be understood and improved if necessary, and a control strategy can be defined to manage risk and ensure the method performs as desired when validated and deployed. In this review, the current state of analytical QbD in the industry is detailed with examples of the application of analytical QbD principles to a range of analytical methods, including high-performance liquid chromatography, Karl Fischer titration for moisture content, vibrational spectroscopy for chemical identification, quantitative color measurement, and trace analysis for genotoxic impurities. Copyright © 2010 Wiley-Liss, Inc.

  14. Validation of a simultaneous analytical method for the detection of 27 benzodiazepines and metabolites and zolpidem in hair using LC-MS/MS and its application to human and rat hair.

    Science.gov (United States)

    Kim, Jihyun; Lee, Sooyeun; In, Sanghwan; Choi, Hwakyung; Chung, Heesun

    2011-04-15

    Benzodiazepines and zolpidem are controlled in many countries due to their inherent adverse effects of a high degree of tolerance and dependence. Recently, as some of these drugs have become distributed illegally and available through media such as the Internet, their abuse is becoming a serious social problem. Hair is a useful specimen to prove chronic drug use. In the present study, a simultaneous analytical method for the detection of 27 benzodiazepines and metabolites and zolpidem in hair was established and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The drugs and their metabolites in hair were extracted using methanol, filtered and injected on the LC-MS/MS. The following validation parameters of the method were satisfactory: selectivity, linearity, matrix effect, recovery, process efficiency, intra- and inter-assay precision and accuracy and processed sample stability. The limit of detection (LOD) and the limit of quantification (LOQ) were the total drug detected from the sample. The LODs ranged from 0.005 ng (zolpidem) to 0.5 ng (bromazepam and chlordiazepoxide) and the LOQs were 0.25 ng in every analyte except for bromazepam and chlordiazepoxide, for which they were 0.5 ng. The developed method was successfully applied to five legal cases involving use of benzodiazepines and zolpidem and to an animal study on drug incorporation into hair. Diazepam and its three metabolites, as well as lorazepam, were detected in hair from both the multiple- and single-dose administration groups of lean Zucker rats. The concentration of diazepam was higher than those of its metabolites in both dark grey and white hair from the multiple-dose administration groups, with the mean concentration ranges from 0.16 to 0.51 ng/mg and from 0.10 to 0.24 ng/mg, respectively. The mean concentration ranges of lorazepam were from 0.05 to 0.37 ng/mg in dark grey hair and from 0.11 to 0.45 ng/mg in white hair from the multiple-dose administration groups. Hair

  15. LATUX: An Iterative Workflow for Designing, Validating, and Deploying Learning Analytics Visualizations

    Science.gov (United States)

    Martinez-Maldonado, Roberto; Pardo, Abelardo; Mirriahi, Negin; Yacef, Kalina; Kay, Judy; Clayphan, Andrew

    2015-01-01

    Designing, validating, and deploying learning analytics tools for instructors or students is a challenge that requires techniques and methods from different disciplines, such as software engineering, human-computer interaction, computer graphics, educational design, and psychology. Whilst each has established its own design methodologies, we now…

  16. Nuclear analytical methods for platinum group elements

    International Nuclear Information System (INIS)

    2005-04-01

    Platinum group elements (PGE) are of special interest for analytical research due to their economic importance like chemical peculiarities as catalysts, medical applications as anticancer drugs, and possible environmental detrimental impact as exhaust from automobile catalyzers. Natural levels of PGE are so low in concentration that most of the current analytical techniques approach their limit of detection capacity. In addition, Ru, Rh, Pd, Re, Os, Ir, and Pt analyses still constitute a challenge in accuracy and precision of quantification in natural matrices. Nuclear analytical techniques, such as neutron activation analysis, X ray fluorescence, or proton-induced X ray emission (PIXE), which are generally considered as reference methods for many analytical problems, are useful as well. However, due to methodological restrictions, they can, in most cases, only be applied after pre-concentration and under special irradiation conditions. This report was prepared following a coordinated research project and a consultants meeting addressing the subject from different viewpoints. The experts involved suggested to discuss the issue according to the (1) application, hence, the concentration levels encountered, and (2) method applied for analysis. Each of the different fields of application needs special consideration for sample preparation, PGE pre-concentration, and determination. Additionally, each analytical method requires special attention regarding the sensitivity and sample type. Quality assurance/quality control aspects are considered towards the end of the report. It is intended to provide the reader of this publication with state-of-the-art information on the various aspects of PGE analysis and to advise which technique might be most suitable for a particular analytical problem related to platinum group elements. In particular, many case studies described in detail from the authors' laboratory experience might help to decide which way to go. As in many cases

  17. Structurally compliant rocket engine combustion chamber: Experimental and analytical validation

    Science.gov (United States)

    Jankovsky, Robert S.; Arya, Vinod K.; Kazaroff, John M.; Halford, Gary R.

    1994-03-01

    A new, structurally compliant rocket engine combustion chamber design has been validated through analysis and experiment. Subscale, tubular channel chambers have been cyclically tested and analytically evaluated. Cyclic lives were determined to have a potential for 1000 percent increase over those of rectangular channel designs, the current state of the art. Greater structural compliance in the circumferential direction gave rise to lower thermal strains during hot firing, resulting in lower thermal strain ratcheting and longer predicted fatigue lives. Thermal, structural, and durability analyses of the combustion chamber design, involving cyclic temperatures, strains, and low-cycle fatigue lives, have corroborated the experimental observations.

  18. Comparison of nuclear analytical methods with competitive methods

    International Nuclear Information System (INIS)

    1987-10-01

    The use of nuclear analytical techniques, especially neutron activation analysis, already have a 50 year old history. Today several sensitive and accurate, non-nuclear trace element analytical techniques are available and new methods are continuously developed. The IAEA is supporting the development of nuclear analytical laboratories in its Member States. In order to be able to advise the developing countries which methods to use in different applications, it is important to know the present status and development trends of nuclear analytical methods, what are their benefits, drawbacks and recommended fields of application, compared with other, non-nuclear techniques. In order to get an answer to these questions the IAEA convened this Advisory Group Meeting. This volume is the outcome of the presentations and discussions of the meeting. A separate abstract was prepared for each of the 21 papers. Refs, figs, tabs

  19. Preliminary Assessment of ATR-C Capabilities to Provide Integral Benchmark Data for Key Structural/Matrix Materials that May be Used for Nuclear Data Testing and Analytical Methods Validation

    Energy Technology Data Exchange (ETDEWEB)

    John D. Bess

    2009-03-01

    The purpose of this research is to provide a fundamental computational investigation into the possible integration of experimental activities with the Advanced Test Reactor Critical (ATR-C) facility with the development of benchmark experiments. Criticality benchmarks performed in the ATR-C could provide integral data for key matrix and structural materials used in nuclear systems. Results would then be utilized in the improvement of nuclear data libraries and as a means for analytical methods validation. It is proposed that experiments consisting of well-characterized quantities of materials be placed in the Northwest flux trap position of the ATR-C. The reactivity worth of the material could be determined and computationally analyzed through comprehensive benchmark activities including uncertainty analyses. Experiments were modeled in the available benchmark model of the ATR using MCNP5 with the ENDF/B-VII.0 cross section library. A single bar (9.5 cm long, 0.5 cm wide, and 121.92 cm high) of each material could provide sufficient reactivity difference in the core geometry for computational modeling and analysis. However, to provide increased opportunity for the validation of computational models, additional bars of material placed in the flux trap would increase the effective reactivity up to a limit of 1$ insertion. For simplicity in assembly manufacture, approximately four bars of material could provide a means for additional experimental benchmark configurations, except in the case of strong neutron absorbers and many materials providing positive reactivity. Future tasks include the cost analysis and development of the experimental assemblies, including means for the characterization of the neutron flux and spectral indices. Oscillation techniques may also serve to provide additional means for experimentation and validation of computational methods and acquisition of integral data for improving neutron cross sections. Further assessment of oscillation

  20. Preliminary Assessment of ATR-C Capabilities to Provide Integral Benchmark Data for Key Structural/Matrix Materials that May be Used for Nuclear Data Testing and Analytical Methods Validation

    Energy Technology Data Exchange (ETDEWEB)

    John D. Bess

    2009-07-01

    The purpose of this document is to identify some suggested types of experiments that can be performed in the Advanced Test Reactor Critical (ATR-C) facility. A fundamental computational investigation is provided to demonstrate possible integration of experimental activities in the ATR-C with the development of benchmark experiments. Criticality benchmarks performed in the ATR-C could provide integral data for key matrix and structural materials used in nuclear systems. Results would then be utilized in the improvement of nuclear data libraries and as a means for analytical methods validation. It is proposed that experiments consisting of well-characterized quantities of materials be placed in the Northwest flux trap position of the ATR-C. The reactivity worth of the material could be determined and computationally analyzed through comprehensive benchmark activities including uncertainty analyses. Experiments were modeled in the available benchmark model of the ATR using MCNP5 with the ENDF/B-VII.0 cross section library. A single bar (9.5 cm long, 0.5 cm wide, and 121.92 cm high) of each material could provide sufficient reactivity difference in the core geometry for computational modeling and analysis. However, to provide increased opportunity for the validation of computational models, additional bars of material placed in the flux trap would increase the effective reactivity up to a limit of 1$ insertion. For simplicity in assembly manufacture, approximately four bars of material could provide a means for additional experimental benchmark configurations, except in the case of strong neutron absorbers and many materials providing positive reactivity. Future tasks include the cost analysis and development of the experimental assemblies, including means for the characterization of the neutron flux and spectral indices. Oscillation techniques may also serve to provide additional means for experimentation and validation of computational methods and acquisition of

  1. Modern methods in analytical acoustics lecture notes

    CERN Document Server

    Crighton, D G; Williams, J E Ffowcs; Heckl, M; Leppington, F G

    1992-01-01

    Modern Methods in Analytical Acoustics considers topics fundamental to the understanding of noise, vibration and fluid mechanisms. The series of lectures on which this material is based began by some twenty five years ago and has been developed and expanded ever since. Acknowledged experts in the field have given this course many times in Europe and the USA. Although the scope of the course has widened considerably, the primary aim of teaching analytical techniques of acoustics alongside specific areas of wave motion and unsteady fluid mechanisms remains. The distinguished authors of this volume are drawn from Departments of Acoustics, Engineering of Applied Mathematics in Berlin, Cambridge and London. Their intention is to reach a wider audience of all those concerned with acoustic analysis than has been able to attend the course.

  2. Big data analytics methods and applications

    CERN Document Server

    Rao, BLS; Rao, SB

    2016-01-01

    This book has a collection of articles written by Big Data experts to describe some of the cutting-edge methods and applications from their respective areas of interest, and provides the reader with a detailed overview of the field of Big Data Analytics as it is practiced today. The chapters cover technical aspects of key areas that generate and use Big Data such as management and finance; medicine and healthcare; genome, cytome and microbiome; graphs and networks; Internet of Things; Big Data standards; bench-marking of systems; and others. In addition to different applications, key algorithmic approaches such as graph partitioning, clustering and finite mixture modelling of high-dimensional data are also covered. The varied collection of themes in this volume introduces the reader to the richness of the emerging field of Big Data Analytics.

  3. Directory of Analytical Methods, Department 1820

    International Nuclear Information System (INIS)

    Whan, R.E.

    1986-01-01

    The Materials Characterization Department performs chemical, physical, and thermophysical analyses in support of programs throughout the Laboratories. The department has a wide variety of techniques and instruments staffed by experienced personnel available for these analyses, and we strive to maintain near state-of-the-art technology by continued updates. We have prepared this Directory of Analytical Methods in order to acquaint you with our capabilities and to help you identify personnel who can assist with your analytical needs. The descriptions of the various capabilities are requester-oriented and have been limited in length and detail. Emphasis has been placed on applications and limitations with notations of estimated analysis time and alternative or related techniques. A short, simplified discussion of underlying principles is also presented along with references if more detail is desired. The contents of this document have been organized in the order: bulky analysis, microanalysis, surface analysis, optical and thermal property measurements

  4. Analytical Methods of Decoupling the Automotive Engine Torque Roll Axis

    Science.gov (United States)

    JEONG, TAESEOK; SINGH, RAJENDRA

    2000-06-01

    This paper analytically examines the multi-dimensional mounting schemes of an automotive engine-gearbox system when excited by oscillating torques. In particular, the issue of torque roll axis decoupling is analyzed in significant detail since it is poorly understood. New dynamic decoupling axioms are presented an d compared with the conventional elastic axis mounting and focalization methods. A linear time-invariant system assumption is made in addition to a proportionally damped system. Only rigid-body modes of the powertrain are considered and the chassis elements are assumed to be rigid. Several simplified physical systems are considered and new closed-form solutions for symmetric and asymmetric engine-mounting systems are developed. These clearly explain the design concepts for the 4-point mounting scheme. Our analytical solutions match with the existing design formulations that are only applicable to symmetric geometries. Spectra for all six rigid-body motions are predicted using the alternate decoupling methods and the closed-form solutions are verified. Also, our method is validated by comparing modal solutions with prior experimental and analytical studies. Parametric design studies are carried out to illustrate the methodology. Chief contributions of this research include the development of new or refined analytical models and closed-form solutions along with improved design strategies for the torque roll axis decoupling.

  5. The Emergence of the Analytical Method

    DEFF Research Database (Denmark)

    Plum, Maja

    2012-01-01

    accountability, visibility and documentation. It is argued that pedagogy is generated as a sequential and unit-specified way of working on the production of ‘the learning child’, forming a time- and material-optimising approach. Hereby, the nursery teacher, as a daily scientific researcher, comes to serve...... the nation by an ongoing observational intervention, producing the learning foundation for the entrepreneurial citizen, and thus the nation as a knowledge society in a globalised world. This is what this article terms the emergence of the analytical method....

  6. Analytical chromatography. Methods, instrumentation and applications

    International Nuclear Information System (INIS)

    Yashin, Ya I; Yashin, A Ya

    2006-01-01

    The state-of-the-art and the prospects in the development of main methods of analytical chromatography, viz., gas, high performance liquid and ion chromatographic techniques, are characterised. Achievements of the past 10-15 years in the theory and general methodology of chromatography and also in the development of new sorbents, columns and chromatographic instruments are outlined. The use of chromatography in the environmental control, biology, medicine, pharmaceutics, and also for monitoring the quality of foodstuffs and products of chemical, petrochemical and gas industries, etc. is considered.

  7. Analytical N beam position monitor method

    Science.gov (United States)

    Wegscheider, A.; Langner, A.; Tomás, R.; Franchi, A.

    2017-11-01

    Measurement and correction of focusing errors is of great importance for performance and machine protection of circular accelerators. Furthermore LHC needs to provide equal luminosities to the experiments ATLAS and CMS. High demands are also set on the speed of the optics commissioning, as the foreseen operation with β*-leveling on luminosity will require many operational optics. A fast measurement of the β -function around a storage ring is usually done by using the measured phase advance between three consecutive beam position monitors (BPMs). A recent extension of this established technique, called the N-BPM method, was successfully applied for optics measurements at CERN, ALBA, and ESRF. We present here an improved algorithm that uses analytical calculations for both random and systematic errors and takes into account the presence of quadrupole, sextupole, and BPM misalignments, in addition to quadrupolar field errors. This new scheme, called the analytical N-BPM method, is much faster, further improves the measurement accuracy, and is applicable to very pushed beam optics where the existing numerical N-BPM method tends to fail.

  8. Validated Analytical Model of a Pressure Compensation Drip Irrigation Emitter

    Science.gov (United States)

    Shamshery, Pulkit; Wang, Ruo-Qian; Taylor, Katherine; Tran, Davis; Winter, Amos

    2015-11-01

    This work is focused on analytically characterizing the behavior of pressure-compensating drip emitters in order to design low-cost, low-power irrigation solutions appropriate for off-grid communities in developing countries. There are 2.5 billion small acreage farmers worldwide who rely solely on their land for sustenance. Drip, compared to flood, irrigation leads to up to 70% reduction in water consumption while increasing yields by 90% - important in countries like India which are quickly running out of water. To design a low-power drip system, there is a need to decrease the pumping pressure requirement at the emitters, as pumping power is the product of pressure and flow rate. To efficiently design such an emitter, the relationship between the fluid-structure interactions that occur in an emitter need to be understood. In this study, a 2D analytical model that captures the behavior of a common drip emitter was developed and validated through experiments. The effects of independently changing the channel depth, channel width, channel length and land height on the performance were studied. The model and the key parametric insights presented have the potential to be optimized in order to guide the design of low-pressure, clog-resistant, pressure-compensating emitters.

  9. Determination of elements by nuclear analytical methods.

    Science.gov (United States)

    Weise, H P; Görner, W; Hedrich, M

    2001-01-01

    The working principle of nuclear analytical methods (NAMs) is not influenced by the chemical bond. Consequently, they are independent counterparts to the well-known chemical procedures. NAMs obey fundamental laws or can be described and understood thoroughly. This qualifies them as candidates for reference methods. Although following similar nuclear reaction schemes, they comprise bulk analyzing capability (neutron and photon activation analysis) as well as detection power in surface near regions of solids (ion beam techniques). Prominent features of NAMs are sensitivity, selectivity, multielement determination and linearity of the calibration function covering a concentration range of several orders of magnitude. Moreover, ion beam techniques allow depth profiling with nm-resolution in several cases while the ion microprobe additionally offers a lateral resolution in the micron-scale. As NAMs require expensive apparatus (nuclear reactor, accelerator in radioactive control areas) their availability is restricted to a small number of suitably equipped institutes. However, they are able to solve complex analytical tasks, take part in key comparisons and play an essential role in the certification of reference materials.

  10. Analytical Methods in Tracing Honey Authenticity.

    Science.gov (United States)

    Trifković, Jelena; Andrić, Filip; Ristivojević, Petar; Guzelmeric, Etil; Yesilada, Erdem

    2017-07-01

    Honey is a precious natural product that is marketed with a wide range of nutritional and medicinal properties. However, it is also a product subjected to frequent adulteration through mislabeling and mixing with cheaper and lower-quality honeys and various sugar syrups. In that sense, honey authentication regarding its genuine botanical and geographical origins, as well as the detection of any adulteration, is essential in order to protect consumer health and to avoid competition that could create a destabilized market. Various analytical techniques have been developed to detect adulterations in honey, including measuring the ratios of stable isotopes (mostly 13C/12C) and the use of different spectroscopic, chromatographic, and electrochemical methods. This review aims to provide a cross-section of contemporary analytical methods used for the determination of honey authenticity in order to help the scientific community engaged in the field of honey chemistry make appropriate choices and select the best applications that should lead to improvements in the detection and elimination of fraudulent practices in honey manufacturing.

  11. Model-Based Method for Sensor Validation

    Science.gov (United States)

    Vatan, Farrokh

    2012-01-01

    Fault detection, diagnosis, and prognosis are essential tasks in the operation of autonomous spacecraft, instruments, and in situ platforms. One of NASA s key mission requirements is robust state estimation. Sensing, using a wide range of sensors and sensor fusion approaches, plays a central role in robust state estimation, and there is a need to diagnose sensor failure as well as component failure. Sensor validation can be considered to be part of the larger effort of improving reliability and safety. The standard methods for solving the sensor validation problem are based on probabilistic analysis of the system, from which the method based on Bayesian networks is most popular. Therefore, these methods can only predict the most probable faulty sensors, which are subject to the initial probabilities defined for the failures. The method developed in this work is based on a model-based approach and provides the faulty sensors (if any), which can be logically inferred from the model of the system and the sensor readings (observations). The method is also more suitable for the systems when it is hard, or even impossible, to find the probability functions of the system. The method starts by a new mathematical description of the problem and develops a very efficient and systematic algorithm for its solution. The method builds on the concepts of analytical redundant relations (ARRs).

  12. Radiochemical methods. Analytical chemistry by open learning

    Energy Technology Data Exchange (ETDEWEB)

    Geary, W.J.; James, A.M. (ed.)

    1986-01-01

    This book presents the analytical uses of radioactive isotopes within the context of radiochemistry as a whole. It is designed for scientists with relatively little background knowledge of the subject. Thus the initial emphasis is on developing the basic concepts of radioactive decay, particularly as they affect the potential usage of radioisotopes. Discussion of the properties of various types of radiation, and of factors such as half-life, is related to practical considerations such as counting and preparation methods, and handling/disposal problems. Practical aspects are then considered in more detail, and the various radioanalytical methods are outlined with particular reference to their applicability. The approach is 'user friendly' and the use of self assessment questions allows the reader to test his/her understanding of individual sections easily. For those who wish to develop their knowledge further, a reading list is provided.

  13. A confirmatory factor analytic validation of the Tinnitus Handicap Inventory.

    Science.gov (United States)

    Kleinstäuber, Maria; Frank, Ina; Weise, Cornelia

    2015-03-01

    Because the postulated three-factor structure of the internationally widely used Tinnitus Handicap Inventory (THI) has not been confirmed yet by a confirmatory factor analytic approach this was the central aim of the current study. From a clinical setting, N=373 patients with chronic tinnitus completed the THI and further questionnaires assessing tinnitus-related and psychological variables. In order to analyze the psychometric properties of the THI, confirmatory factor analysis (CFA) and correlational analyses were conducted. CFA provided a statistically significant support for a better fit of the data to the hypothesized three-factor structure (RMSEA=.049, WRMR=1.062, CFI=.965, TLI=.961) than to a general factor model (RMSEA=.062, WRMR=1.258, CFI=.942, TLI=.937). The calculation of Cronbach's alpha as indicator of internal consistency revealed satisfactory values (.80-.91) with the exception of the catastrophic subscale (.65). High positive correlations of the THI and its subscales with other measures of tinnitus distress, anxiety, and depression, high negative correlations with tinnitus acceptance, moderate positive correlations with anxiety sensitivity, sleeping difficulties, tinnitus loudness, and small correlations with the Big Five personality dimensions confirmed construct validity. Results show that the THI is a highly reliable and valid measure of tinnitus-related handicap. In contrast to results of previous exploratory analyses the current findings speak for a three-factor in contrast to a unifactorial structure. Future research is needed to replicate this result in different tinnitus populations. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Analytical methods to assess nanoparticle toxicity.

    Science.gov (United States)

    Marquis, Bryce J; Love, Sara A; Braun, Katherine L; Haynes, Christy L

    2009-03-01

    During the past 20 years, improvements in nanoscale materials synthesis and characterization have given scientists great control over the fabrication of materials with features between 1 and 100 nm, unlocking many unique size-dependent properties and, thus, promising many new and/or improved technologies. Recent years have found the integration of such materials into commercial goods; a current estimate suggests there are over 800 nanoparticle-containing consumer products (The Project on Emerging Nanotechnologies Consumer Products Inventory, , accessed Oct. 2008), accounting for 147 billion USD in products in 2007 (Nanomaterials state of the market Q3 2008: stealth success, broad impact, Lux Research Inc., New York, NY, 2008). Despite this increase in the prevalence of engineered nanomaterials, there is little known about their potential impacts on environmental health and safety. The field of nanotoxicology has formed in response to this lack of information and resulted in a flurry of research studies. Nanotoxicology relies on many analytical methods for the characterization of nanomaterials as well as their impacts on in vitro and in vivo function. This review provides a critical overview of these techniques from the perspective of an analytical chemist, and is intended to be used as a reference for scientists interested in conducting nanotoxicological research as well as those interested in nanotoxicological assay development.

  15. Analytic Method for Computing Instrument Pointing Jitter

    Science.gov (United States)

    Bayard, David

    2003-01-01

    A new method of calculating the root-mean-square (rms) pointing jitter of a scientific instrument (e.g., a camera, radar antenna, or telescope) is introduced based on a state-space concept. In comparison with the prior method of calculating the rms pointing jitter, the present method involves significantly less computation. The rms pointing jitter of an instrument (the square root of the jitter variance shown in the figure) is an important physical quantity which impacts the design of the instrument, its actuators, controls, sensory components, and sensor- output-sampling circuitry. Using the Sirlin, San Martin, and Lucke definition of pointing jitter, the prior method of computing the rms pointing jitter involves a frequency-domain integral of a rational polynomial multiplied by a transcendental weighting function, necessitating the use of numerical-integration techniques. In practice, numerical integration complicates the problem of calculating the rms pointing error. In contrast, the state-space method provides exact analytic expressions that can be evaluated without numerical integration.

  16. Analytical method for Buddleja colorants in foods.

    Science.gov (United States)

    Aoki, H; Kuze, N; Ichi, T; Koda, T

    2001-04-01

    Buddleja yellow colorant derived from Buddleja officinalis Maxim. has recently been approved for use as a new kind of natural colorant for food additives in China. In order to distinguish Buddleja yellow colorant from other yellow colorants, two known phenylpropanoid glycosides, acteoside (= verbascoside) and poliumoside, were isolated from the colorant as marker substances for Buddleja yellow colorant. Poliumoside has not been detected in B. officinalis Maxim. previously. These phenylpropanoid glycosides were not detected in the fruits of Gardenia jasminoides Ellis or in the stamens of the flowers of Crocus sativus L., which also contain crocetin derivatives as coloring components, using a photodiode array and mass chromatograms. Thus, an analytical HPLC method was developed to distinguish foods that have been colored with yellow colorants containing crocetin derivatives, using phenylpropanoid glycosides as markers.

  17. Analytical method for high resolution liquid chromatography for quality control French Macaw

    International Nuclear Information System (INIS)

    Garcia Penna, Caridad M; Torres Amaro, Leonid; Menendez Castillo, Rosa; Sanchez, Esther; Martinez Espinosa, Vivian; Gonzalez, Maria Lidia; Rodriguez, Carlos

    2007-01-01

    Was developed and validated an analytical method for high resolution liquid chromatography applicable to quality control of drugs dry French Macaw (Senna alata L. Roxb.) With ultraviolet detection at 340 nm. The method for high resolution liquid chromatography used to quantify the sennosides A and B, main components, was validated and proved to be specific, linear, precise and accurate. (Author)

  18. Validación de métodos analíticos de control de procesos de antitumorales inyectables Analytical methods validation of processes control in injectable antitumor agents

    Directory of Open Access Journals (Sweden)

    Caridad Margarita García Peña

    2010-03-01

    Full Text Available Se validaron los métodos analíticos alternativos para el control de proceso de fluorouracilo 500 mg, doxorrubicina 50 mg y metotrexato 50 mg por espectrofotometría, por ser estos métodos más sencillos, económicos, que permiten controlar la calidad de los medicamentos en el análisis de control de proceso. Las curvas de calibración del fluorouracilo, la doxorrubicina y el metotrexato, se realizaron en el intervalo de 60 al 140 %, donde fueron lineales con coeficientes de correlación iguales a 0,9998; 0,9999 y 0,9999, respectivamente; la prueba estadística para el intercepto y la pendiente se consideraron no significativas. Se obtuvieron recobrados del 99,97, 99,08 y 99,35 %, respectivamente en el intervalo de concentraciones estudiado, y las pruebas de Cochran y t de Student resultaron no significativas. Los coeficientes de variación de los estudios de la repetibilidad fueron inferiores al 3 % para las 6 réplicas ensayadas, mientras que en los análisis de la precisión intermedia las pruebas de Fischer y t de Student indicaron diferencias no significativas. Los métodos resultaron específicos, lineales, precisos y exactos en el intervalo de concentraciones estudiadas.Alternative analytical methods were validated for the process control of 500 mg florouacil, 50 mg doxorrubicin and 50 mg methotrexate by spectrophotometry because of they are more simple and economic allowint to control the drugs quality in process anaslysis control. Calibration curves of fluorouracil, doxorrubicin and methotrexate were plotted in interval from 60 to 140 %, where there were linear with correlation coeficients similar to 0.9998, 0.9999 and 0.9999, respectively; statistical text for intercept and slope were considered as non-significant. Recoveries of 99.97, 99.98 and 99.35 % were achieved, respectively in study concentration interval and Cochran and t-Student tests were also non-significant. Methods were specific, linear, precises and exacts in interval

  19. Evolution of microbiological analytical methods for dairy industry needs

    Directory of Open Access Journals (Sweden)

    Daniele eSohier

    2014-02-01

    Full Text Available Traditionally, culture-based methods have been used to enumerate microbial populations in dairy products. Recent developments in molecular methods now enable faster and more sensitive analyses than classical microbiology procedures. These molecular tools allow a detailed characterization of cell physiological states and bacterial fitness and thus, offer new perspectives to integration of microbial physiology monitoring to improve industrial processes. This review summarizes the methods described to enumerate and characterize physiological states of technological microbiota in dairy products, and discusses the current deficiencies in relation to the industry’s needs. Recent studies show that PCR-based methods can successfully be applied to quantify fermenting microbes and probiotics in dairy products. Flow cytometry and omics technologies also show interesting analytical potentialities. However, they still suffer from a lack of validation and standardization for quality control analyses, as reflected by the absence of performance studies and official international standards.

  20. Validation of an advanced analytical procedure applied to the measurement of environmental radioactivity.

    Science.gov (United States)

    Thanh, Tran Thien; Vuong, Le Quang; Ho, Phan Long; Chuong, Huynh Dinh; Nguyen, Vo Hoang; Tao, Chau Van

    2018-04-01

    In this work, an advanced analytical procedure was applied to calculate radioactivity in spiked water samples in a close geometry gamma spectroscopy. It included MCNP-CP code in order to calculate the coincidence summing correction factor (CSF). The CSF results were validated by a deterministic method using ETNA code for both p-type HPGe detectors. It showed that a good agreement for both codes. Finally, the validity of the developed procedure was confirmed by a proficiency test to calculate the activities of various radionuclides. The results of the radioactivity measurement with both detectors using the advanced analytical procedure were received the ''Accepted'' statuses following the proficiency test. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Hanford environmental analytical methods: Methods as of March 1990

    International Nuclear Information System (INIS)

    Goheen, S.C.; McCulloch, M.; Daniel, J.L.

    1993-05-01

    This paper from the analytical laboratories at Hanford describes the method used to measure pH of single-shell tank core samples. Sludge or solid samples are mixed with deionized water. The pH electrode used combines both a sensor and reference electrode in one unit. The meter amplifies the input signal from the electrode and displays the pH visually

  2. Microgenetic Learning Analytics Methods: Workshop Report

    Science.gov (United States)

    Aghababyan, Ani; Martin, Taylor; Janisiewicz, Philip; Close, Kevin

    2016-01-01

    Learning analytics is an emerging discipline and, as such, benefits from new tools and methodological approaches. This work reviews and summarizes our workshop on microgenetic data analysis techniques using R, held at the second annual Learning Analytics Summer Institute in Cambridge, Massachusetts, on 30 June 2014. Specifically, this paper…

  3. Validación de un método analítico empleando cromatografía líquida de alta eficiencia para la determinación de ibuprofeno en medios biorrelevantes Validation of an analytical method by liquid chromatography for determination of ibuprofen in biorelevant media

    Directory of Open Access Journals (Sweden)

    Sandra M. Gómez

    2010-01-01

    Full Text Available An analytical method by liquid chromatography has been proposed and validated to study the apparent solubility of ibuprofen in biorelevant dissolution media. The main properties of the studied media were pH values of 5.0 and 6.5 and the presence or absence of some natural surfactant agents. The parameters evaluated were specificity, linearity, precision, accuracy, and detection and quantification limits, as well as the drug stability under the analysis conditions. The developed method was useful to determine the apparent solubility of this drug as a function of temperature and surfactants concentration to demonstrate the validity of the Biopharmaceutics Classification System.

  4. Analytical Method to Estimate the Complex Permittivity of Oil Samples

    Directory of Open Access Journals (Sweden)

    Lijuan Su

    2018-03-01

    Full Text Available In this paper, an analytical method to estimate the complex dielectric constant of liquids is presented. The method is based on the measurement of the transmission coefficient in an embedded microstrip line loaded with a complementary split ring resonator (CSRR, which is etched in the ground plane. From this response, the dielectric constant and loss tangent of the liquid under test (LUT can be extracted, provided that the CSRR is surrounded by such LUT, and the liquid level extends beyond the region where the electromagnetic fields generated by the CSRR are present. For that purpose, a liquid container acting as a pool is added to the structure. The main advantage of this method, which is validated from the measurement of the complex dielectric constant of olive and castor oil, is that reference samples for calibration are not required.

  5. ANALYTICAL METHODS FOR CALCULATING FAN AERODYNAMICS

    Directory of Open Access Journals (Sweden)

    Jan Dostal

    2015-12-01

    Full Text Available This paper presents results obtained between 2010 and 2014 in the field of fan aerodynamics at the Department of Composite Technology at the VZLÚ aerospace research and experimental institute in Prague – Letnany. The need for rapid and accurate methods for the preliminary design of blade machinery led to the creation of a mathematical model based on the basic laws of turbomachine aerodynamics. The mathematical model, the derivation of which is briefly described below, has been encoded in a computer programme, which enables the theoretical characteristics of a fan of the designed geometry to be determined rapidly. The validity of the mathematical model is assessed continuously by measuring model fans in the measuring unit, which was developed and manufactured specifically for this purpose. The paper also presents a comparison between measured characteristics and characteristics determined by the mathematical model as the basis for a discussion on possible causes of measured deviations and calculation deviations.

  6. Class-modelling in food analytical chemistry: Development, sampling, optimisation and validation issues - A tutorial.

    Science.gov (United States)

    Oliveri, Paolo

    2017-08-22

    Qualitative data modelling is a fundamental branch of pattern recognition, with many applications in analytical chemistry, and embraces two main families: discriminant and class-modelling methods. The first strategy is appropriate when at least two classes are meaningfully defined in the problem under study, while the second strategy is the right choice when the focus is on a single class. For this reason, class-modelling methods are also referred to as one-class classifiers. Although, in the food analytical field, most of the issues would be properly addressed by class-modelling strategies, the use of such techniques is rather limited and, in many cases, discriminant methods are forcedly used for one-class problems, introducing a bias in the outcomes. Key aspects related to the development, optimisation and validation of suitable class models for the characterisation of food products are critically analysed and discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Optimization and validation of a GC-MS analytical method for the determination of alkylated phenols and bisphenol A in sea water and suspended matter; Optimierung und Validierung einer GC-MS-Analysenmethode zur Bestimmung alkylierter Phenole und Bisphenol A in Meerwasser und Schwebstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Theobald, N.; Meyer, C.

    2001-12-01

    A method for the determination of alkylated phenols, phenol ethoxylates and bisphenol A in surface and sea water was optimized and validated. The analytical procedure consists of a liquid/liquid extraction with dichloromethane, a derivatisation with bis(heptafluorobutyric) anhydride and a GC-MS determination in EI-mode under selected ion monitoring condition. The validation parameters such as measuring precision, method precision, linearity, limits of determination, accuracy and robustness were determined. Very good results were achieved for all parameters. It turned out that the problem of contamination has to be observed very carefully. The method validation was supported by organising and performing two ring tests. For the first test, spiked samples of ultra-clean water were analysed. For the second test spiked river and sea water samples were investigated. The results show that the presented method is capable for monitoring purposes within the Bund-Laender-Messprogramm. (orig.)

  8. 7 CFR 94.4 - Analytical methods.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) COMMODITY LABORATORY TESTING PROGRAMS...) FDA Bacteriological Analytical Manual (BAM), AOAC INTERNATIONAL, 481 North Frederick Avenue, Suite 500...

  9. Validation of a horizontal method for trace elements in soil, sludge and biowaste

    OpenAIRE

    CRISTACHE CARMEN-ILEANA; COMERO Sara; LOCORO Giovanni; FISSIAUX ISABELLE; ALONSO RUIZ AGUSTIN; TANET GERARD; GAWLIK Bernd

    2013-01-01

    Validation of an analytical method is a necessary step in controlling the quality of quantitative analysis. Method validation is an established process, which is the provision of documentary evidence that a system fulfils its pre-defined specification or the process of providing that an analytical method is acceptable for its intended purpose. To implement a validated method for the analysis of 22000 soil samples stemming from 2009 LUCAS Soil Survey as well as from sewage sludge and treat...

  10. 40 CFR 425.03 - Sulfide analytical methods and applicability.

    Science.gov (United States)

    2010-07-01

    ... § 425.03 Sulfide analytical methods and applicability. (a) The potassium ferricyanide titration method... ferricyanide titration method for the determination of sulfide in wastewaters discharged by plants operating in... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Sulfide analytical methods and...

  11. An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders - A Reference Solution for the Numerical Method of Auxiliary Sources

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    2004-01-01

    To facilitate the validation of the numerical Method of Auxiliary Sources an analytical Method of Auxiliary Sources solution is derived in this paper. The Analytical solution is valid for transverse magnetic, and electric, plane wave scattering by circular impedance Cylinders, and it is derived b...

  12. Sensor Network Information Analytical Methods: Analysis of Similarities and Differences

    Directory of Open Access Journals (Sweden)

    Chen Jian

    2014-04-01

    Full Text Available In the Sensor Network information engineering literature, few references focus on the definition and design of Sensor Network information analytical methods. Among those that do are Munson, et al. and the ISO standards on functional size analysis. To avoid inconsistent vocabulary and potentially incorrect interpretation of data, Sensor Network information analytical methods must be better designed, including definitions, analysis principles, analysis rules, and base units. This paper analyzes the similarities and differences across three different views of analytical methods, and uses a process proposed for the design of Sensor Network information analytical methods to analyze two examples of such methods selected from the literature.

  13. Evaluation and analytical validation of a handheld digital refractometer for urine specific gravity measurement

    Directory of Open Access Journals (Sweden)

    Sara P. Wyness

    2016-08-01

    Full Text Available Objectives: Refractometers are commonly used to determine urine specific gravity (SG in the assessment of hydration status and urine specimen validity testing. Few comprehensive performance evaluations are available demonstrating refractometer capability from a clinical laboratory perspective. The objective of this study was therefore to conduct an analytical validation of a handheld digital refractometer used for human urine SG testing. Design and methods: A MISCO Palm Abbe™ refractometer was used for all experiments, including device familiarization, carryover, precision, accuracy, linearity, analytical sensitivity, evaluation of potential substances which contribute to SG (i.e. “interference”, and reference interval evaluation. A manual refractometer, urine osmometer, and a solute score (sum of urine chloride, creatinine, glucose, potassium, sodium, total protein, and urea nitrogen; all in mg/dL were used as comparative methods for accuracy assessment. Results: Significant carryover was not observed. A wash step was still included as good laboratory practice. Low imprecision (%CV, <0.01 was demonstrated using low and high QC material. Accuracy studies showed strong correlation to manual refractometry. Linear correlation was also demonstrated between SG, osmolality, and solute score. Linearity of Palm Abbe performance was verified with observed error of ≤0.1%. Increases in SG were observed with increasing concentrations of albumin, creatinine, glucose, hemoglobin, sodium chloride, and urea. Transference of a previously published urine SG reference interval of 1.0020–1.0300 was validated. Conclusions: The Palm Abbe digital refractometer was a fast, simple, and accurate way to measure urine SG. Analytical validity was confirmed by the present experiments. Keywords: Specific gravity, Osmolality, Digital refractometry, Hydration, Sports medicine, Urine drug testing, Urine adulteration

  14. Method development and validations: characterization of critical ...

    African Journals Online (AJOL)

    Method development and validations: characterization of critical elements in the development of pharmaceuticals. ... International Journal of Health Research ... Although a thorough validation cannot rule out all potential problems, the process of method development and validation should address the most common ones.

  15. Nonlinear ordinary differential equations analytical approximation and numerical methods

    CERN Document Server

    Hermann, Martin

    2016-01-01

    The book discusses the solutions to nonlinear ordinary differential equations (ODEs) using analytical and numerical approximation methods. Recently, analytical approximation methods have been largely used in solving linear and nonlinear lower-order ODEs. It also discusses using these methods to solve some strong nonlinear ODEs. There are two chapters devoted to solving nonlinear ODEs using numerical methods, as in practice high-dimensional systems of nonlinear ODEs that cannot be solved by analytical approximate methods are common. Moreover, it studies analytical and numerical techniques for the treatment of parameter-depending ODEs. The book explains various methods for solving nonlinear-oscillator and structural-system problems, including the energy balance method, harmonic balance method, amplitude frequency formulation, variational iteration method, homotopy perturbation method, iteration perturbation method, homotopy analysis method, simple and multiple shooting method, and the nonlinear stabilized march...

  16. A comparison of direct and indirect analytical methods of computing ...

    African Journals Online (AJOL)

    The first step in the analysis of gravity anomalies for mineral exploration is the extraction of residual gravity anomalies from the observed gravity anomalies. This can be achieved by graphical or analytical methods. Generally, direct and indirect analytical methods are considered better than graphical methods. Telford et al ...

  17. Analytical validation of a next generation sequencing liquid biopsy assay for high sensitivity broad molecular profiling.

    Science.gov (United States)

    Plagnol, Vincent; Woodhouse, Samuel; Howarth, Karen; Lensing, Stefanie; Smith, Matt; Epstein, Michael; Madi, Mikidache; Smalley, Sarah; Leroy, Catherine; Hinton, Jonathan; de Kievit, Frank; Musgrave-Brown, Esther; Herd, Colin; Baker-Neblett, Katherine; Brennan, Will; Dimitrov, Peter; Campbell, Nathan; Morris, Clive; Rosenfeld, Nitzan; Clark, James; Gale, Davina; Platt, Jamie; Calaway, John; Jones, Greg; Forshew, Tim

    2018-01-01

    Circulating tumor DNA (ctDNA) analysis is being incorporated into cancer care; notably in profiling patients to guide treatment decisions. Responses to targeted therapies have been observed in patients with actionable mutations detected in plasma DNA at variant allele fractions (VAFs) below 0.5%. Highly sensitive methods are therefore required for optimal clinical use. To enable objective assessment of assay performance, detailed analytical validation is required. We developed the InVisionFirst™ assay, an assay based on enhanced tagged amplicon sequencing (eTAm-Seq™) technology to profile 36 genes commonly mutated in non-small cell lung cancer (NSCLC) and other cancer types for actionable genomic alterations in cell-free DNA. The assay has been developed to detect point mutations, indels, amplifications and gene fusions that commonly occur in NSCLC. For analytical validation, two 10mL blood tubes were collected from NSCLC patients and healthy volunteer donors. In addition, contrived samples were used to represent a wide spectrum of genetic aberrations and VAFs. Samples were analyzed by multiple operators, at different times and using different reagent Lots. Results were compared with digital PCR (dPCR). The InVisionFirst assay demonstrated an excellent limit of detection, with 99.48% sensitivity for SNVs present at VAF range 0.25%-0.33%, 92.46% sensitivity for indels at 0.25% VAF and a high rate of detection at lower frequencies while retaining high specificity (99.9997% per base). The assay also detected ALK and ROS1 gene fusions, and DNA amplifications in ERBB2, FGFR1, MET and EGFR with high sensitivity and specificity. Comparison between the InVisionFirst assay and dPCR in a series of cancer patients showed high concordance. This analytical validation demonstrated that the InVisionFirst assay is highly sensitive, specific and robust, and meets analytical requirements for clinical applications.

  18. Validation of an analytical method for nitrous oxide (N2O) laughing gas by headspace gas chromatography coupled to mass spectrometry (HS-GC-MS): forensic application to a lethal intoxication.

    Science.gov (United States)

    Giuliani, N; Beyer, J; Augsburger, M; Varlet, V

    2015-03-01

    Drug abuse is a widespread problem affecting both teenagers and adults. Nitrous oxide is becoming increasingly popular as an inhalation drug, causing harmful neurological and hematological effects. Some gas chromatography-mass spectrometry (GC-MS) methods for nitrous oxide measurement have been previously described. The main drawbacks of these methods include a lack of sensitivity for forensic applications; including an inability to quantitatively determine the concentration of gas present. The following study provides a validated method using HS-GC-MS which incorporates hydrogen sulfide as a suitable internal standard allowing the quantification of nitrous oxide. Upon analysis, sample and internal standard have similar retention times and are eluted quickly from the molecular sieve 5Å PLOT capillary column and the Porabond Q column therefore providing rapid data collection whilst preserving well defined peaks. After validation, the method has been applied to a real case of N2O intoxication indicating concentrations in a mono-intoxication. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Recent developments in analytical detection methods for radiation processed foods

    International Nuclear Information System (INIS)

    Wu Jilan

    1993-01-01

    A short summary of the programmes of 'ADMIT' (FAO/IAEA) and the developments in analytical detection methods for radiation processed foods has been given. It is suggested that for promoting the commercialization of radiation processed foods and controlling its quality, one must pay more attention to the study of analytical detection methods of irradiated food

  20. An Analytical Procedure for the Equipercentile Method of Equating Tests.

    Science.gov (United States)

    Lindsay, Carl A.; Prichard, Mark A.

    Prior use of the equipercentile method of test equating was based on a graphic procedure which is tedious, subject to smoothing errors, and non-analytical. Recognition of the equipercentile method as a curve-fitting procedure for two cumulative percentage distributions leads to a proposed analytical solution to the problem through use of linear…

  1. A comparison between analytic and numerical methods for modelling automotive dissipative silencers with mean flow

    Science.gov (United States)

    Kirby, R.

    2009-08-01

    Identifying an appropriate method for modelling automotive dissipative silencers normally requires one to choose between analytic and numerical methods. It is common in the literature to justify the choice of an analytic method based on the assumption that equivalent numerical techniques are more computationally expensive. The validity of this assumption is investigated here, and the relative speed and accuracy of two analytic methods are compared to two numerical methods for a uniform dissipative silencer that contains a bulk reacting porous material separated from a mean gas flow by a perforated pipe. The numerical methods are developed here with a view to speeding up transmission loss computation, and are based on a mode matching scheme and a hybrid finite element method. The results presented demonstrate excellent agreement between the analytic and numerical models provided a sufficient number of propagating acoustic modes are retained. However, the numerical mode matching method is shown to be the fastest method, significantly outperforming an equivalent analytic technique. Moreover, the hybrid finite element method is demonstrated to be as fast as the analytic technique. Accordingly, both numerical techniques deliver fast and accurate predictions and are capable of outperforming equivalent analytic methods for automotive dissipative silencers.

  2. Approximate Analytic and Numerical Solutions to Lane-Emden Equation via Fuzzy Modeling Method

    Directory of Open Access Journals (Sweden)

    De-Gang Wang

    2012-01-01

    Full Text Available A novel algorithm, called variable weight fuzzy marginal linearization (VWFML method, is proposed. This method can supply approximate analytic and numerical solutions to Lane-Emden equations. And it is easy to be implemented and extended for solving other nonlinear differential equations. Numerical examples are included to demonstrate the validity and applicability of the developed technique.

  3. An Iteration Method Generating Analytical Solutions for Blasius Problem

    OpenAIRE

    Yun, Beong In

    2011-01-01

    We derive a new iteration method for finding solution of the generalized Blasius problem. This method results in the analytical series solutions which are consistent with the existing series solutions for some special cases.

  4. A REVIEW: AN APPROACH TOWARDS THE ANALYTICAL METHOD DEVELOPMENT FOR DETERMINATION OF NEWER DRUGS

    OpenAIRE

    Kirtimaya Mishra*, Dr. K. Balamurugan1, Dr. R. Suresh1

    2017-01-01

    In this present scenario for treating various diseases several new drugs were invented. Before launching to the market these drugs must undergo analytical validation process. In this review some of analytical techniques such as ultraviolet/ visible spectrophotometry, fluorimetry, capillary electrophoresis, and chromatographic methods (gas chromatography and high-performance liquid chromatography), LC-MS, GC-MS, SOLID PHASE EXTRACTION, NMR, MASS Spectrophotometry LC/MS/MS LC/UV X-ray crystallo...

  5. Valid analytical performance specifications for combined analytical bias and imprecision for the use of common reference intervals.

    Science.gov (United States)

    Hyltoft Petersen, Per; Lund, Flemming; Fraser, Callum G; Sandberg, Sverre; Sölétormos, György

    2018-01-01

    Background Many clinical decisions are based on comparison of patient results with reference intervals. Therefore, an estimation of the analytical performance specifications for the quality that would be required to allow sharing common reference intervals is needed. The International Federation of Clinical Chemistry (IFCC) recommended a minimum of 120 reference individuals to establish reference intervals. This number implies a certain level of quality, which could then be used for defining analytical performance specifications as the maximum combination of analytical bias and imprecision required for sharing common reference intervals, the aim of this investigation. Methods Two methods were investigated for defining the maximum combination of analytical bias and imprecision that would give the same quality of common reference intervals as the IFCC recommendation. Method 1 is based on a formula for the combination of analytical bias and imprecision and Method 2 is based on the Microsoft Excel formula NORMINV including the fractional probability of reference individuals outside each limit and the Gaussian variables of mean and standard deviation. The combinations of normalized bias and imprecision are illustrated for both methods. The formulae are identical for Gaussian and log-Gaussian distributions. Results Method 2 gives the correct results with a constant percentage of 4.4% for all combinations of bias and imprecision. Conclusion The Microsoft Excel formula NORMINV is useful for the estimation of analytical performance specifications for both Gaussian and log-Gaussian distributions of reference intervals.

  6. Validation of NAA Method for Urban Particulate Matter

    International Nuclear Information System (INIS)

    Woro Yatu Niken Syahfitri; Muhayatun; Diah Dwiana Lestiani; Natalia Adventini

    2009-01-01

    Nuclear analytical techniques have been applied in many countries for determination of environmental pollutant. Method of NAA (neutron activation analysis) representing one of nuclear analytical technique of that has low detection limits, high specificity, high precision, and accuracy for large majority of naturally occurring elements, and ability of non-destructive and simultaneous determination of multi-elemental, and can handle small sample size (< 1 mg). To ensure quality and reliability of the method, validation are needed to be done. A standard reference material, SRM NIST 1648 Urban Particulate Matter, has been used to validate NAA method. Accuracy and precision test were used as validation parameters. Particulate matter were validated for 18 elements: Ti, I, V, Br, Mn, Na, K, Cl, Cu, Al, As, Fe, Co, Zn, Ag, La, Cr, and Sm,. The result showed that the percent relative standard deviation of the measured elemental concentrations are found to be within ranged from 2 to 14,8% for most of the elements analyzed whereas Hor rat value in range 0,3-1,3. Accuracy test results showed that relative bias ranged from -11,1 to 3,6%. Based on validation results, it can be stated that NAA method is reliable for characterization particulate matter and other similar matrix samples to support air quality monitoring. (author)

  7. Valid analytical performance specifications for combined analytical bias and imprecision for the use of common reference intervals

    DEFF Research Database (Denmark)

    Hyltoft Petersen, Per; Lund, Flemming; Fraser, Callum G

    2018-01-01

    Background Many clinical decisions are based on comparison of patient results with reference intervals. Therefore, an estimation of the analytical performance specifications for the quality that would be required to allow sharing common reference intervals is needed. The International Federation...... of Clinical Chemistry (IFCC) recommended a minimum of 120 reference individuals to establish reference intervals. This number implies a certain level of quality, which could then be used for defining analytical performance specifications as the maximum combination of analytical bias and imprecision required...... for sharing common reference intervals, the aim of this investigation. Methods Two methods were investigated for defining the maximum combination of analytical bias and imprecision that would give the same quality of common reference intervals as the IFCC recommendation. Method 1 is based on a formula...

  8. Determination of aluminum by four analytical methods

    International Nuclear Information System (INIS)

    Hanson, T.J.; Smetana, K.M.

    1975-11-01

    Four procedures have been developed for determining the aluminum concentration in basic matrices. Atomic Absorption Spectroscopy (AAS) was the routine method of analysis. Citrate was required to complex the aluminum and eliminate matrix effects. AAS was the least accurate of the four methods studied and was adversely affected by high aluminum concentrations. The Fluoride Electrode Method was the most accurate and precise of the four methods. A Gran's Plot determination was used to determine the end point and average standard recovery was 100% +- 2%. The Thermometric Titration Method was the fastest method for determining aluminum and could also determine hydroxide concentration at the same time. Standard recoveries were 100% +- 5%. The pH Electrode Method also measures aluminum and hydroxide content simultaneously, but is less accurate and more time consuming that the thermal titration. Samples were analyzed using all four methods and results were compared to determine the strengths and weaknesses of each. On the basis of these comparisons, conclusions were drawn concerning the application of each method to our laboratory needs

  9. Learner Language Analytic Methods and Pedagogical Implications

    Science.gov (United States)

    Dyson, Bronwen

    2010-01-01

    Methods for analysing interlanguage have long aimed to capture learner language in its own right. By surveying the cognitive methods of Error Analysis, Obligatory Occasion Analysis and Frequency Analysis, this paper traces reformulations to attain this goal. The paper then focuses on Emergence Analysis, which fine-tunes learner language analysis…

  10. Finite analytic method for modeling variably saturated flows.

    Science.gov (United States)

    Zhang, Zaiyong; Wang, Wenke; Gong, Chengcheng; Yeh, Tian-Chyi Jim; Wang, Zhoufeng; Wang, Yu-Li; Chen, Li

    2018-04-15

    This paper develops a finite analytic method (FAM) for solving the two-dimensional Richards' equation. The FAM incorporates the analytic solution in local elements to formulate the algebraic representation of the partial differential equation of unsaturated flow so as to effectively control both numerical oscillation and dispersion. The FAM model is then verified using four examples, in which the numerical solutions are compared with analytical solutions, solutions from VSAFT2, and observational data from a field experiment. These numerical experiments show that the method is not only accurate but also efficient, when compared with other numerical methods. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Rat brain polyamines: an analytical method validation Poliaminas no cérebro do rato: validação de método analítico

    Directory of Open Access Journals (Sweden)

    Valdomiro de Freitas Sampaio

    2010-12-01

    Full Text Available The validation of the analytical technique for the determination of polyamines in cerebral tissue using HPLC based on o-phthalaldehyde post-column derivatization is described. The polyamines were separated in a LiChrospher100 RP18 column. Elution gradient was formed with two mobile phases: A (sodium acetate 0.1 M + sodium octanesulphonate 0.01 M, pH = 4.5 and B (sodium acetate 0.2 M + sodium octanesulphonate 0.01 M/acetonitrile (10:3, pH = 4.5 in a 1.2 ml/min flow rate. The derivative eluent was monitored by fluorescence (excitation, 345 nm; emission, 455 nm. Besides excellent linearity (putrescine, r = 0.9816; spermidine, r = 0.9920; spermine, r = 0.9901, the technique demonstrated intra and inter-day precision (A validação técnica analítica para determinação de poliaminas em tecido cerebral utilizando cromotografia líquida de alta eficiência (HPLC e derivação pós-coluna com o-ftaldialdeído é descrita. A separação das poliaminas deu-se em coluna LiChrospher 100 RP18. O gradiente de eluição foi formado por duas fases móveis A (acetato de sódio 0,1M + octanossulfonato de sódio 0,01 M e B (acetato de sódio 0,2 M + octanossulfonato de sódio 0,01 M/acetonitrila (10:3, fluxo de 1,2 ml/min. O eluente foi monitorado por fluorescência (excitação, 345 nm; emissão, 455 nm. Além da excelente linearidade (putrescina, r = 0,9816; espermidina, r = 0,9920; espermina, r = 0,9901, a técnica demonstrou adequada precisão intra e interdia (< 20% e recuperação (espermidina = 92,56%; espermina = 84,47%. Os limites de quantificação foram 0,22 pM para putrescina, 76,44 pM para espermidina e 51,44 pM para espermina. O método demonstrou ser consistente, simples e altamente reprodutível para a determinação proposta.

  12. Multicenter validation of the analytical accuracy of Salmonella PCR: towards an international standard

    DEFF Research Database (Denmark)

    Malorny, B.; Hoorfar, Jeffrey; Bunge, C.

    2003-01-01

    As part of a major international project for the validation and standardization of PCR for detection of five major food-borne pathogens, four primer sets specific for Salmonella species were evaluated in-house for their analytical accuracy (selectivity and detection limit) in identifying 43 Salmo...... and is proposed as an international standard. This study addresses the increasing demand of quality assurance laboratories for standard diagnostic methods and presents findings that can facilitate the international comparison and exchange of epidemiological data.......As part of a major international project for the validation and standardization of PCR for detection of five major food-borne pathogens, four primer sets specific for Salmonella species were evaluated in-house for their analytical accuracy (selectivity and detection limit) in identifying 43...... of selectivity by using 364 strains showed that the inclusivity was 99.6% and the exclusivity was 100% for the invA primer set. To indicate possible PCR inhibitors derived from the sample DNA, an internal amplification control (IAC), which was coamplified with the invA target gene, was constructed...

  13. Analytical method for establishing indentation rolling resistance

    Science.gov (United States)

    Gładysiewicz, Lech; Konieczna, Martyna

    2018-01-01

    Belt conveyors are highly reliable machines able to work in special operating conditions. Harsh environment, long distance of transporting and great mass of transported martials are cause of high energy usage. That is why research in the field of belt conveyor transportation nowadays focuses on reducing the power consumption without lowering their efficiency. In this paper, previous methods for testing rolling resistance are described, and new method designed by authors was presented. New method of testing rolling resistance is quite simple and inexpensive. Moreover it allows to conduct the experimental tests of the impact of different parameters on the value of indentation rolling resistance such as core design, cover thickness, ambient temperature, idler travel frequency, or load value as well. Finally results of tests of relationship between rolling resistance and idler travel frequency and between rolling resistance and idler travel speed was presented.

  14. Surveillance of emerging drugs of abuse in Hong Kong: validation of an analytical tool.

    Science.gov (United States)

    Tang, Magdalene H Y; Ching, C K; Tse, M L; Ng, Carol; Lee, Caroline; Chong, Y K; Wong, Watson; Mak, Tony W L

    2015-04-01

    To validate a locally developed chromatography-based method to monitor emerging drugs of abuse whilst performing regular drug testing in abusers. Cross-sectional study. Eleven regional hospitals, seven social service units, and a tertiary level clinical toxicology laboratory in Hong Kong. A total of 972 drug abusers and high-risk individuals were recruited from acute, rehabilitation, and high-risk settings between 1 November 2011 and 31 July 2013. A subset of the participants was of South Asian ethnicity. In total, 2000 urine or hair specimens were collected. Proof of concept that surveillance of emerging drugs of abuse can be performed whilst conducting routine drug of abuse testing in patients. The method was successfully applied to 2000 samples with three emerging drugs of abuse detected in five samples: PMMA (paramethoxymethamphetamine), TFMPP [1-(3-trifluoromethylphenyl)piperazine], and methcathinone. The method also detected conventional drugs of abuse, with codeine, methadone, heroin, methamphetamine, and ketamine being the most frequently detected drugs. Other findings included the observation that South Asians had significantly higher rates of using opiates such as heroin, methadone, and codeine; and that ketamine and cocaine had significantly higher detection rates in acute subjects compared with the rehabilitation population. This locally developed analytical method is a valid tool for simultaneous surveillance of emerging drugs of abuse and routine drug monitoring of patients at minimal additional cost and effort. Continued, proactive surveillance and early identification of emerging drugs will facilitate prompt clinical, social, and legislative management.

  15. Spacecraft early design validation using formal methods

    NARCIS (Netherlands)

    Bozzano, Marco; Cimatti, Alessandro; Katoen, Joost P.; Katsaros, Panagiotis; Mokos, Konstantinos; Nguyen, Viet Yen; Noll, Thomas; Postma, Bart; Roveri, Marco

    2014-01-01

    The size and complexity of software in spacecraft is increasing exponentially, and this trend complicates its validation within the context of the overall spacecraft system. Current validation methods are labor-intensive as they rely on manual analysis, review and inspection. For future space

  16. An analytic parton shower. Algorithms, implementation and validation

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Sebastian

    2012-06-15

    The realistic simulation of particle collisions is an indispensable tool to interpret the data measured at high-energy colliders, for example the now running Large Hadron Collider at CERN. These collisions at these colliders are usually simulated in the form of exclusive events. This thesis focuses on the perturbative QCD part involved in the simulation of these events, particularly parton showers and the consistent combination of parton showers and matrix elements. We present an existing parton shower algorithm for emissions off final state partons along with some major improvements. Moreover, we present a new parton shower algorithm for emissions off incoming partons. The aim of these particular algorithms, called analytic parton shower algorithms, is to be able to calculate the probabilities for branchings and for whole events after the event has been generated. This allows a reweighting procedure to be applied after the events have been simulated. We show a detailed description of the algorithms, their implementation and the interfaces to the event generator WHIZARD. Moreover we discuss the implementation of a MLM-type matching procedure and an interface to the shower and hadronization routines from PYTHIA. Finally, we compare several predictions by our implementation to experimental measurements at LEP, Tevatron and LHC, as well as to predictions obtained using PYTHIA. (orig.)

  17. An analytic parton shower. Algorithms, implementation and validation

    International Nuclear Information System (INIS)

    Schmidt, Sebastian

    2012-06-01

    The realistic simulation of particle collisions is an indispensable tool to interpret the data measured at high-energy colliders, for example the now running Large Hadron Collider at CERN. These collisions at these colliders are usually simulated in the form of exclusive events. This thesis focuses on the perturbative QCD part involved in the simulation of these events, particularly parton showers and the consistent combination of parton showers and matrix elements. We present an existing parton shower algorithm for emissions off final state partons along with some major improvements. Moreover, we present a new parton shower algorithm for emissions off incoming partons. The aim of these particular algorithms, called analytic parton shower algorithms, is to be able to calculate the probabilities for branchings and for whole events after the event has been generated. This allows a reweighting procedure to be applied after the events have been simulated. We show a detailed description of the algorithms, their implementation and the interfaces to the event generator WHIZARD. Moreover we discuss the implementation of a MLM-type matching procedure and an interface to the shower and hadronization routines from PYTHIA. Finally, we compare several predictions by our implementation to experimental measurements at LEP, Tevatron and LHC, as well as to predictions obtained using PYTHIA. (orig.)

  18. Validación de métodos analíticos para el control de calidad de naproxeno supositorios Validation of analytical methods for the quality control of Naproxen suppositories

    Directory of Open Access Journals (Sweden)

    Yaslenis Rodríguez Hernández

    2011-09-01

    Full Text Available En el presente trabajo se desarrollaron por primera vez, los métodos de análisis que serán utilizados para el control de calidad de las futuras formulaciones de supositorios de naproxeno, para uso infantil y adulto de producción nacional. Se propuso un método por espectrofotometría ultravioleta directa, el cual resultó específico, lineal, exacto y preciso para su aplicación en el control de calidad del naproxeno en supositorios, teniendo en cuenta la presencia de grupos cromóforos en su estructura. Se modificó el método por volumetría ácido-base semiacuosa directa reportado para control de calidad de la materia prima de naproxeno y se adaptó al control de calidad en los supositorios. A partir del proceso de validación realizado, se demostró la adecuada especificidad frente a los componentes de la formulación, así como su linealidad, exactitud y precisión en el rango de 1 a 3 mg/mL. Se compararon los resultados obtenidos por ambos métodos sin detectar diferencias estadísticamente significativas entre las réplicas analizadas por cada dosis, por lo que cualquiera de ellos pueden aplicarse al control de calidad de los supositorios.The analysis methods that will be used for the quality control of the future Cuban-made Naproxen suppositories for adults and children were developed for the first time in this paper. One method based on direct ultraviolet spectrophotometry was put forward, which proved to be specific, linear, accurate and precise for the quality control of Naproxen suppositories, taking into account the presence of chromophore groups in their structure. Likewise, the direct semi-aqueous acid-base volumetry method aimed at the quality control of the Naproxen raw material was changed and adapted to the quality control of suppositories. On the basis of the validation process, there was demonstrated the adequate specificity of this method with respect to the formulation components, as well as its linearity, accuracy and

  19. Validation of ultraviolet method to determine serum phosphorus level

    International Nuclear Information System (INIS)

    Garcia Borges, Lisandra; Perez Prieto, Teresa Maria; Valdes Diez, Lilliam

    2009-01-01

    Validation of a spectrophotometry method applicable in clinic labs was proposed to analytical assessment of serum phosphates using a kit UV-phosphorus of domestic production from 'Carlos J. Finlay' Biologics Production Enterprise (Havana, Cuba). Analysis method was based on phosphorus reaction to ammonium molybdenum to acid pH to creating a measurable complex to 340 nm. Specificity and precision were measured considering the method strength, linearity, accuracy and sensitivity. Analytical method was linear up to 4,8 mmol/L, precise (CV 30 .999) during clinical interest concentration interval where there were not interferences by matrix. Detection limit values were of 0.037 mmol/L and of quantification of 0.13 mmol/L both were satisfactory for product use

  20. An analytic solution for numerical modeling validation in electromagnetics: the resistive sphere

    Science.gov (United States)

    Swidinsky, Andrei; Liu, Lifei

    2017-11-01

    We derive the electromagnetic response of a resistive sphere to an electric dipole source buried in a conductive whole space. The solution consists of an infinite series of spherical Bessel functions and associated Legendre polynomials, and follows the well-studied problem of a conductive sphere buried in a resistive whole space in the presence of a magnetic dipole. Our result is particularly useful for controlled-source electromagnetic problems using a grounded electric dipole transmitter and can be used to check numerical methods of calculating the response of resistive targets (such as finite difference, finite volume, finite element and integral equation). While we elect to focus on the resistive sphere in our examples, the expressions in this paper are completely general and allow for arbitrary source frequency, sphere radius, transmitter position, receiver position and sphere/host conductivity contrast so that conductive target responses can also be checked. Commonly used mesh validation techniques consist of comparisons against other numerical codes, but such solutions may not always be reliable or readily available. Alternatively, the response of simple 1-D models can be tested against well-known whole space, half-space and layered earth solutions, but such an approach is inadequate for validating models with curved surfaces. We demonstrate that our theoretical results can be used as a complementary validation tool by comparing analytic electric fields to those calculated through a finite-element analysis; the software implementation of this infinite series solution is made available for direct and immediate application.

  1. Validated High Performance Liquid Chromatography Method for ...

    African Journals Online (AJOL)

    capsules and dry powder for oral suspension, manufactured by local and multinational companies. It is an official monograph in United. States Pharmacopeia (USP) [3]. Cefadroxil monohydrate has been quantitatively determined in biological fluids, including plasma, serum, and urine [4-16]. Many analytical methods were.

  2. An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders - A Reference Solution for the Numerical Method of Auxiliary Sources

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    2004-01-01

    To facilitate the validation of the numerical Method of Auxiliary Sources an analytical Method of Auxiliary Sources solution is derived in this paper. The Analytical solution is valid for transverse magnetic, and electric, plane wave scattering by circular impedance Cylinders, and it is derived...... of the numerical Method of Auxiliary Sources for a range of scattering configurations....... with their singularities at different positions away from the origin. The transformation necessitates a truncation of the wave transformation but the inaccuracy introduced hereby is shown to be negligible. The analytical Method of Auxiliary Sources solution is employed as a reference to investigate the accuracy...

  3. Comparative Analytical Methods for the Measurment of Chlorine Dioxide

    OpenAIRE

    Desai, Unmesh Jeetendra

    2002-01-01

    Four commercially available methods used for the analysis of low-level Chlorine Dioxide (ClO2) concentrations in drinking water were evaluated for accuracy and precision and ranked according to cost, efficiency and ease of the methods under several conditions that might be encountered at water treatment plants. The different analytical methods included: 1.The DPD (N, N-diethyl-p-phenylenediamine) method 2.Lissamine Green B (LGB) wet-chemical method 3.Palintest® kit LGB 4.A...

  4. Validation of the analytical methodology for evaluation of lapachol in solution by HPCL

    OpenAIRE

    Fonseca, Said G. C.; Silva, Leila B. L. da; Castro, Rebeka F.; Santana, Davi P. de

    2004-01-01

    Lapachol is a naphthoquinone found in several species of the Bignoniaceae family possessing mainly anticancer activity. The present work consists of the development and validation of analytical methodology for lapachol and its preparations. The results here obtained show that lapachol has a low quantification limit, that the analytical methodology is accurate, reproducible, robust and linear over the concentration range 0.5-100 µg/mL of lapachol.

  5. Analytical methods for quantitation of prenylated flavonoids from hops

    Science.gov (United States)

    Nikolić, Dejan; van Breemen, Richard B.

    2013-01-01

    The female flowers of hops (Humulus lupulus L.) are used as a flavoring agent in the brewing industry. There is growing interest in possible health benefits of hops, particularly as estrogenic and chemopreventive agents. Among the possible active constituents, most of the attention has focused on prenylated flavonoids, which can chemically be classified as prenylated chalcones and prenylated flavanones. Among chalcones, xanthohumol (XN) and desmethylxanthohumol (DMX) have been the most studied, while among flavanones, 8-prenylnaringenin (8-PN) and 6-prenylnaringenin (6-PN) have received the most attention. Because of the interest in medicinal properties of prenylated flavonoids, there is demand for accurate, reproducible and sensitive analytical methods to quantify these compounds in various matrices. Such methods are needed, for example, for quality control and standardization of hop extracts, measurement of the content of prenylated flavonoids in beer, and to determine pharmacokinetic properties of prenylated flavonoids in animals and humans. This review summarizes currently available analytical methods for quantitative analysis of the major prenylated flavonoids, with an emphasis on the LC-MS and LC-MS-MS methods and their recent applications to biomedical research on hops. This review covers all methods in which prenylated flavonoids have been measured, either as the primary analytes or as a part of a larger group of analytes. The review also discusses methodological issues relating to the quantitative analysis of these compounds regardless of the chosen analytical approach. PMID:24077106

  6. Lack of correlation between reaction speed and analytical sensitivity in isothermal amplification reveals the value of digital methods for optimization: validation using digital real-time RT-LAMP.

    Science.gov (United States)

    Khorosheva, Eugenia M; Karymov, Mikhail A; Selck, David A; Ismagilov, Rustem F

    2016-01-29

    In this paper, we asked if it is possible to identify the best primers and reaction conditions based on improvements in reaction speed when optimizing isothermal reactions. We used digital single-molecule, real-time analyses of both speed and efficiency of isothermal amplification reactions, which revealed that improvements in the speed of isothermal amplification reactions did not always correlate with improvements in digital efficiency (the fraction of molecules that amplify) or with analytical sensitivity. However, we observed that the speeds of amplification for single-molecule (in a digital device) and multi-molecule (e.g. in a PCR well plate) formats always correlated for the same conditions. Also, digital efficiency correlated with the analytical sensitivity of the same reaction performed in a multi-molecule format. Our finding was supported experimentally with examples of primer design, the use or exclusion of loop primers in different combinations, and the use of different enzyme mixtures in one-step reverse-transcription loop-mediated amplification (RT-LAMP). Our results show that measuring the digital efficiency of amplification of single-template molecules allows quick, reliable comparisons of the analytical sensitivity of reactions under any two tested conditions, independent of the speeds of the isothermal amplification reactions. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  7. Analytic methods for field induced tunneling in quantum wells with ...

    Indian Academy of Sciences (India)

    Electric field induced tunneling is studied in three different types of quantum wells by solving time-independent effective mass equation in analytic methods based on three different Airy function approaches. Comparison of different Airy function methods indicates that they are identical and connected to each other by the ...

  8. A simple regularization method for stable analytic continuation

    Science.gov (United States)

    Fu, Chu-Li; Dou, Fang-Fang; Feng, Xiao-Li; Qian, Zhi

    2008-12-01

    The problems of analytic continuation are frequently encountered in many practical applications. These problems are well known to be severely ill-posed and therefore several regularization methods have been suggested for solving them. In this paper we consider the problem of analytic continuation of the analytic function f(z) = f(x + iy) on a strip domain \\Omega=\\{z=x+iy\\in {\\bb C}|x\\in{\\bb R},|y|\\leq y_0\\} , where the data are given only on the line y = 0. We use a very simple and convenient method—the Fourier regularization method to solve this problem. Some sharp error estimates between the exact solution and its approximation are given and numerical examples show the method works effectively. The project is supported by the National Natural Science Foundation of China (Nos. 10671085, 10571079 and 10726017).

  9. Validated modified Lycopodium spore method development for ...

    African Journals Online (AJOL)

    Validated modified lycopodium spore method has been developed for simple and rapid quantification of herbal powdered drugs. Lycopodium spore method was performed on ingredients of Shatavaryadi churna, an ayurvedic formulation used as immunomodulator, galactagogue, aphrodisiac and rejuvenator. Estimation of ...

  10. ASTM Validates Air Pollution Test Methods

    Science.gov (United States)

    Chemical and Engineering News, 1973

    1973-01-01

    The American Society for Testing and Materials (ASTM) has validated six basic methods for measuring pollutants in ambient air as the first part of its Project Threshold. Aim of the project is to establish nationwide consistency in measuring pollutants; determining precision, accuracy and reproducibility of 35 standard measuring methods. (BL)

  11. Rapid validated liquid chromatographic method coupled with ...

    African Journals Online (AJOL)

    Abstract. Purpose: To develop and validate a fast, sensitive, and simple liquid chromatographic method coupled with tandem mass spectrometry for the ... European Medicines Agency (EMA) guidelines. Results: The proposed method ... that few articles were published for NTB quantification in rat biological fluids and tissues.

  12. Validation of Prototype Continuous Real-Time Vital Signs Video Analytics Monitoring System CCATT Viewer

    Science.gov (United States)

    2018-01-26

    10 3.5 Auxiliary Function and System Pressure Test ............................................................... 11 4.0 VALIDATION IN A REAL TRAUMA...release. Distribution is unlimited. Cleared, 88PA, Case # 2018-0730, 20 Feb 2018. To test the new system’s accuracy, reliability , and robustness, we...AFRL-SA-WP-TR-2018-0003 Validation of Prototype Continuous Real-Time Vital Signs Video Analytics Monitoring System “CCATT Viewer

  13. A Table Lookup Method for Exact Analytical Solutions of Nonlinear Fractional Partial Differential Equations

    Directory of Open Access Journals (Sweden)

    Ji Juan-Juan

    2017-01-01

    Full Text Available A table lookup method for solving nonlinear fractional partial differential equations (fPDEs is proposed in this paper. Looking up the corresponding tables, we can quickly obtain the exact analytical solutions of fPDEs by using this method. To illustrate the validity of the method, we apply it to construct the exact analytical solutions of four nonlinear fPDEs, namely, the time fractional simplified MCH equation, the space-time fractional combined KdV-mKdV equation, the (2+1-dimensional time fractional Zoomeron equation, and the space-time fractional ZKBBM equation. As a result, many new types of exact analytical solutions are obtained including triangular periodic solution, hyperbolic function solution, singular solution, multiple solitary wave solution, and Jacobi elliptic function solution.

  14. Simplified Analytical Methods to Analyze Lock Gates Submitted to Ship Collisions and Earthquakes

    Directory of Open Access Journals (Sweden)

    Buldgen Loic

    2015-09-01

    Full Text Available This paper presents two simplified analytical methods to analyze lock gates submitted to two different accidental loads. The case of an impact involving a vessel is first investigated. In this situation, the resistance of the struck gate is evaluated by assuming a local and a global deforming mode. The super-element method is used in the first case, while an equivalent beam model is simultaneously introduced to capture the overall bending motion of the structure. The second accidental load considered in this paper is the seismic action, for which an analytical method is presented to evaluate the total hydrodynamic pressure applied on a lock gate during an earthquake, due account being taken of the fluid-structure interaction. For each of these two actions, numerical validations are presented and the analytical results are compared to finite-element solutions.

  15. Rigid inclusions-Comparison between analytical and numerical methods

    International Nuclear Information System (INIS)

    Gomez Perez, R.; Melentijevic, S.

    2014-01-01

    This paper compares different analytical methods for analysis of rigid inclusions with finite element modeling. First of all, the load transfer in the distribution layer is analyzed for its different thicknesses and different inclusion grids to define the range between results obtained by analytical and numerical methods. The interaction between the soft soil and the inclusion in the estimation of settlements is studied as well. Considering different stiffness of the soft soil, settlements obtained analytical and numerically are compared. The influence of the soft soil modulus of elasticity on the neutral point depth was also performed by finite elements. This depth has a great importance for the definition of the total length of rigid inclusion. (Author)

  16. Analytical Methods for Detonation Residues of Insensitive Munitions

    Science.gov (United States)

    Walsh, Marianne E.

    2016-01-01

    Analytical methods are described for the analysis of post-detonation residues from insensitive munitions. Standard methods were verified or modified to obtain the mass of residues deposited per round. In addition, a rapid chromatographic separation was developed and used to measure the mass of NTO (3-nitro-1,2,4-triazol-5-one), NQ (nitroguanidine) and DNAN (2,4-dinitroanisole). The HILIC (hydrophilic-interaction chromatography) separation described here uses a trifunctionally-bonded amide phase to retain the polar analytes. The eluent is 75/25 v/v acetonitrile/water acidified with acetic acid, which is also suitable for LC/MS applications. Analytical runtime was three minutes. Solid phase extraction and LC/MS conditions are also described.

  17. SPANDOM - source projection analytic nodal discrete ordinates method

    International Nuclear Information System (INIS)

    Kim, Tae Hyeong; Cho, Nam Zin

    1994-01-01

    We describe a new discrete ordinates nodal method for the two-dimensional transport equation. We solve the discrete ordinates equation analytically after the source term is projected and represented in polynomials. The method is applied to two fast reactor benchmark problems and compared with the TWOHEX code. The results indicate that the present method accurately predicts not only multiplication factor but also flux distribution

  18. 40 CFR 136.6 - Method modifications and analytical requirements.

    Science.gov (United States)

    2010-07-01

    ... must be dechlorinated prior to the addition of such salts. (iii) If the characteristics of a wastewater... matrices; as described in the ATP Protocol, after validation in nine distinct matrices, the method may be...

  19. Analytical validation of a novel multiplex test for detection of advanced adenoma and colorectal cancer in symptomatic patients.

    Science.gov (United States)

    Dillon, Roslyn; Croner, Lisa J; Bucci, John; Kairs, Stefanie N; You, Jia; Beasley, Sharon; Blimline, Mark; Carino, Rochele B; Chan, Vicky C; Cuevas, Danissa; Diggs, Jeff; Jennings, Megan; Levy, Jacob; Mina, Ginger; Yee, Alvin; Wilcox, Bruce

    2018-02-23

    Early detection of colorectal cancer (CRC) is key to reducing associated mortality. Despite the importance of early detection, approximately 40% of individuals in the United States between the ages of 50-75 have never been screened for CRC. The low compliance with colonoscopy and fecal-based screening may be addressed with a non-invasive alternative such as a blood-based test. We describe here the analytical validation of a multiplexed blood-based assay that measures the plasma concentrations of 15 proteins to assess advanced adenoma (AA) and CRC risk in symptomatic patients. The test was developed on an electrochemiluminescent immunoassay platform employing four multi-marker panels, to be implemented in the clinic as a laboratory developed test (LDT). Under the Clinical Laboratory Improvement Amendments (CLIA) and College of American Pathologists (CAP) regulations, a United States-based clinical laboratory utilizing an LDT must establish performance characteristics relating to analytical validity prior to releasing patient test results. This report describes a series of studies demonstrating the precision, accuracy, analytical sensitivity, and analytical specificity for each of the 15 assays, as required by CLIA/CAP. In addition, the report describes studies characterizing each of the assays' dynamic range, parallelism, tolerance to common interfering substances, spike recovery, and stability to sample freeze-thaw cycles. Upon completion of the analytical characterization, a clinical accuracy study was performed to evaluate concordance of AA and CRC classifier model calls using the analytical method intended for use in the clinic. Of 434 symptomatic patient samples tested, the percent agreement with original CRC and AA calls was 87% and 92% respectively. All studies followed CLSI guidelines and met the regulatory requirements for implementation of a new LDT. The results provide the analytical evidence to support the implementation of the novel multi-marker test as

  20. DEVELOPMENT OF AN ANALYTICAL METHOD TO EVALUATE THE INTEGRITY OF A CALANDRIA TUBE IN THE CASE OF PRESSURE TUBE RUPTURE

    OpenAIRE

    森下 善嗣

    1990-01-01

    An analytical method which consists of two‐dimensional thermal‐hydraulic analysis and three‐dimensional structural analysis has been proposed to evaluate the integrity of a calandria tube in the case of pressure tube rupture in a pressure tube type reactor.In order to validate the method,experiments were carried out with coaxially arranged double tubes simulating a pressure tube and a calandria tube.Experimental data were also comparedwith analytical results with the proposed method.

  1. Validación del método analítico para el control de la calidad y estudio de estabilidad de propiltiouracilo 50 mg Analytical method validation for quality control and the study of the 50 mg Propylthiouracil stability

    Directory of Open Access Journals (Sweden)

    María Olga Valdés Bendoyro

    2010-03-01

    Full Text Available Se desarrolló y validó un método analítico por cromatografía líquida de alta resolución, para el control de la calidad y los estudios de estabilidad del propiltiouracilo 50 mg, tabletas. El método se basó en la separación del principio activo a través una columna cromatográfica Lichrospher 100 RP-18 RP-18 (5 µm (250 x 4 mm, con detección ultravioleta a 272 nm, para lo cual se empleó una fase móvil compuesta por una mezcla desgasificada de solución amortiguadora fosfato de potasio monobásico 0,025 M a pH= 4,6, y acetonitrilo en una proporción de 80:20, con una velocidad de flujo de 0,5 mL/min. El método analítico resultó lineal, preciso, específico y exacto en el intervalo de concentraciones estudiadas.A high-performance liquid chromatography analytical method was developed and validated for the quality control and stability studies of 50 mg Propylthiouracil tablets. Method is based in active principle separation through a 100 RP-18 RP-18 (5 µm (250 x 4 mm Lichrospher chromatography with UV detection to 272 nm, using a mobile phase composed by a ungaseous mixture of a 0.025 M buffer solution-monobasic potassium phosphate to pH= 4,6 ad acetonitrile in a 80:20 ratio with a flux speed of 0,5 mL/min. Analytical method was linear, precise, specific and exact in the study concentrations interval.

  2. An analytical software for NAA by using K0-method

    International Nuclear Information System (INIS)

    A Jingye; Chen Da; Tu Jing; Chenweishi; Zhang Wenshou; Wang Daohua

    2003-01-01

    An analytical software has been designed for a personal computer in DOS environment to do reactor NAA by using K 0 -method. The system has functions of radionuclide identification, f and α calculation, K 0 -value calculation, quantitative calculation of elemental concentrations, nuclides' data management, experiment design, computer simulation etc. The analytical methods used in this system include absolute method, relative method and K 0 -method. Using this system, three gamma-ray spectra for NAA of Au, Zr samples and GBW07107 rock standard sample have been analyzed. The analysis results are in agreement with the certified results in the scope of uncertainties and the f and α values at the irradiation site in the UZrH pulse reactor are 36.6 and 0.044 respectively. (author)

  3. Literature Review on Processing and Analytical Methods for ...

    Science.gov (United States)

    Report The purpose of this report was to survey the open literature to determine the current state of the science regarding the processing and analytical methods currently available for recovery of F. tularensis from water and soil matrices, and to determine what gaps remain in the collective knowledge concerning F. tularensis identification from environmental samples.

  4. Frontier in nanoscale flows fractional calculus and analytical methods

    CERN Document Server

    Lewis, Roland; Liu, Hong-yan

    2014-01-01

    This ebook covers the basic properties of nanoscale flows, and various analytical and numerical methods for nanoscale flows and environmental flows. This ebook is a good reference not only for audience of the journal, but also for various communities in mathematics, nanotechnology and environmental science.

  5. An Analytical Method For The Solution Of Reactor Dynamic Equations

    African Journals Online (AJOL)

    Nigeria Journal of Pure and Applied Physics ... One of the challenges of modelling nuclear reactor dynamics on microcomputers is that of finding robust techniques which guarantee the required level of accuracy and at ... In this paper, an analytical method for the solution of nuclear reactor dynamic equations is presented.

  6. Dependability validation by means of fault injection: method, implementation, application

    International Nuclear Information System (INIS)

    Arlat, Jean

    1990-01-01

    This dissertation presents theoretical and practical results concerning the use of fault injection as a means for testing fault tolerance in the framework of the experimental dependability validation of computer systems. The dissertation first presents the state-of-the-art of published work on fault injection, encompassing both hardware (fault simulation, physical fault Injection) and software (mutation testing) issues. Next, the major attributes of fault injection (faults and their activation, experimental readouts and measures, are characterized taking into account: i) the abstraction levels used to represent the system during the various phases of its development (analytical, empirical and physical models), and Il) the validation objectives (verification and evaluation). An evaluation method is subsequently proposed that combines the analytical modeling approaches (Monte Carlo Simulations, closed-form expressions. Markov chains) used for the representation of the fault occurrence process and the experimental fault Injection approaches (fault Simulation and physical injection); characterizing the error processing and fault treatment provided by the fault tolerance mechanisms. An experimental tool - MESSALINE - is then defined and presented. This tool enables physical faults to be Injected In an hardware and software prototype of the system to be validated. Finally, the application of MESSALINE for testing two fault-tolerant systems possessing very dissimilar features and the utilization of the experimental results obtained - both as design feedbacks and for dependability measures evaluation - are used to illustrate the relevance of the method. (author) [fr

  7. An Analytical Method for the Abel Inversion of Asymmetrical Gaussian Profiles

    International Nuclear Information System (INIS)

    Xu Guosheng; Wan Baonian

    2007-01-01

    An analytical algorithm for fast calculation of the Abel inversion for density profile measurement in tokamak is developed. Based upon the assumptions that the particle source is negligibly small in the plasma core region, density profiles can be approximated by an asymmetrical Gaussian distribution controlled only by one parameter V 0 /D and V 0 /D is constant along the radial direction, the analytical algorithm is presented and examined against a testing profile. The validity is confirmed by benchmark with the standard Abel inversion method and the theoretical profile. The scope of application as well as the error analysis is also discussed in detail

  8. Prediction of polymer flooding performance using an analytical method

    International Nuclear Information System (INIS)

    Tan Czek Hoong; Mariyamni Awang; Foo Kok Wai

    2001-01-01

    The study investigated the applicability of an analytical method developed by El-Khatib in polymer flooding. Results from a simulator UTCHEM and experiments were compared with the El-Khatib prediction method. In general, by assuming a constant viscosity polymer injection, the method gave much higher recovery values than the simulation runs and the experiments. A modification of the method gave better correlation, albeit only oil production. Investigation is continuing on modifying the method so that a better overall fit can be obtained for polymer flooding. (Author)

  9. Use of scientometrics to assess nuclear and other analytical methods

    Energy Technology Data Exchange (ETDEWEB)

    Lyon, W.S.

    1986-01-01

    Scientometrics involves the use of quantitative methods to investigate science viewed as an information process. Scientometric studies can be useful in ascertaining which methods have been most employed for various analytical determinations as well as for predicting which methods will continue to be used in the immediate future and which appear to be losing favor with the analytical community. Published papers in the technical literature are the primary source materials for scientometric studies; statistical methods and computer techniques are the tools. Recent studies have included growth and trends in prompt nuclear analysis impact of research published in a technical journal, and institutional and national representation, speakers and topics at several IAEA conferences, at modern trends in activation analysis conferences, and at other non-nuclear oriented conferences. Attempts have also been made to predict future growth of various topics and techniques. 13 refs., 4 figs., 17 tabs.

  10. Use of scientometrics to assess nuclear and other analytical methods

    International Nuclear Information System (INIS)

    Lyon, W.S.

    1986-01-01

    Scientometrics involves the use of quantitative methods to investigate science viewed as an information process. Scientometric studies can be useful in ascertaining which methods have been most employed for various analytical determinations as well as for predicting which methods will continue to be used in the immediate future and which appear to be losing favor with the analytical community. Published papers in the technical literature are the primary source materials for scientometric studies; statistical methods and computer techniques are the tools. Recent studies have included growth and trends in prompt nuclear analysis impact of research published in a technical journal, and institutional and national representation, speakers and topics at several IAEA conferences, at modern trends in activation analysis conferences, and at other non-nuclear oriented conferences. Attempts have also been made to predict future growth of various topics and techniques. 13 refs., 4 figs., 17 tabs

  11. Long-Term Prediction of Satellite Orbit Using Analytical Method

    Directory of Open Access Journals (Sweden)

    Jae-Cheol Yoon

    1997-12-01

    Full Text Available A long-term prediction algorithm of geostationary orbit was developed using the analytical method. The perturbation force models include geopotential upto fifth order and degree and luni-solar gravitation, and solar radiation pressure. All of the perturbation effects were analyzed by secular variations, short-period variations, and long-period variations for equinoctial elements such as the semi-major axis, eccentricity vector, inclination vector, and mean longitude of the satellite. Result of the analytical orbit propagator was compared with that of the cowell orbit propagator for the KOREASAT. The comparison indicated that the analytical solution could predict the semi-major axis with an accuarcy of better than ~35meters over a period of 3 month.

  12. Theological Predication, Doctrinal Location, and Method in Analytic Theology

    Directory of Open Access Journals (Sweden)

    Peterson Ryan S.

    2017-09-01

    Full Text Available Theological method is situated properly in relation to a range of doctrinal commitments, especially commitments located in the doctrines of God, creation, and theological anthropology. In this article, I use Thomas Aquinas’s account of theological predication to illustrate this doctrinal and methodological interconnection. Then, I describe the methodological commitments of analytic theology as they have been articulated by its advocates and argue that analytic theology should embrace an explicitly theological methodology. This requires taking seriously the proper ends of theology and the varied means used by theologians in the Christian theological tradition. I argue that analytic theologians should nurture attentiveness to theology’s chief end (the visio Dei and the corresponding goals of faithful worship and personal formation, the doctrinal order in which specific doctrinal questions find their proper context and location (beginning from and ending with the doctrine of God, and the practices that facilitate good theological judgment-making (prayer and contemplation.

  13. Sampling and analytical methods for atmospheric reduced sulphur compounds

    OpenAIRE

    Cruz, Lícia P. S.; Campos, Vânia P.

    2008-01-01

    This work presents a review of sampling and analytical methods that can be applied to atmospheric traces of reduced sulphur compounds (RSC) in the atmosphere. Sampling methodology involving discontinuous methods with preconcentration is mostly used. For the most part, adsorption on solids and cryogenic capture are applied as a procedure. The analysis of these compounds has been done mainly by gas chromatography with FPD, fluorescence and spectrophotometry. Advantages and disadvantages of the ...

  14. Current analytical methods for plant auxin quantification--A review.

    Science.gov (United States)

    Porfírio, Sara; Gomes da Silva, Marco D R; Peixe, Augusto; Cabrita, Maria J; Azadi, Parastoo

    2016-01-01

    Plant hormones, and especially auxins, are low molecular weight compounds highly involved in the control of plant growth and development. Auxins are also broadly used in horticulture, as part of vegetative plant propagation protocols, allowing the cloning of genotypes of interest. Over the years, large efforts have been put in the development of more sensitive and precise methods of analysis and quantification of plant hormone levels in plant tissues. Although analytical techniques have evolved, and new methods have been implemented, sample preparation is still the limiting step of auxin analysis. In this review, the current methods of auxin analysis are discussed. Sample preparation procedures, including extraction, purification and derivatization, are reviewed and compared. The different analytical techniques, ranging from chromatographic and mass spectrometry methods to immunoassays and electrokinetic methods, as well as other types of detection are also discussed. Considering that auxin analysis mirrors the evolution in analytical chemistry, the number of publications describing new and/or improved methods is always increasing and we considered appropriate to update the available information. For that reason, this article aims to review the current advances in auxin analysis, and thus only reports from the past 15 years will be covered. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Development and in-line validation of a Process Analytical Technology to facilitate the scale up of coating processes.

    Science.gov (United States)

    Wirges, M; Funke, A; Serno, P; Knop, K; Kleinebudde, P

    2013-05-05

    Incorporation of an active pharmaceutical ingredient (API) into the coating layer of film-coated tablets is a method mainly used to formulate fixed-dose combinations. Uniform and precise spray-coating of an API represents a substantial challenge, which could be overcome by applying Raman spectroscopy as process analytical tool. In pharmaceutical industry, Raman spectroscopy is still mainly used as a bench top laboratory analytical method and usually not implemented in the production process. Concerning the application in the production process, a lot of scientific approaches stop at the level of feasibility studies and do not manage the step to production scale and process applications. The present work puts the scale up of an active coating process into focus, which is a step of highest importance during the pharmaceutical development. Active coating experiments were performed at lab and production scale. Using partial least squares (PLS), a multivariate model was constructed by correlating in-line measured Raman spectral data with the coated amount of API. By transferring this model, being implemented for a lab scale process, to a production scale process, the robustness of this analytical method and thus its applicability as a Process Analytical Technology (PAT) tool for the correct endpoint determination in pharmaceutical manufacturing could be shown. Finally, this method was validated according to the European Medicine Agency (EMA) guideline with respect to the special requirements of the applied in-line model development strategy. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Analytical Validation of Accelerator Mass Spectrometry for Pharmaceutical Development: the Measurement of Carbon-14 Isotope Ratio.

    Energy Technology Data Exchange (ETDEWEB)

    Keck, B D; Ognibene, T; Vogel, J S

    2010-02-05

    Accelerator mass spectrometry (AMS) is an isotope based measurement technology that utilizes carbon-14 labeled compounds in the pharmaceutical development process to measure compounds at very low concentrations, empowers microdosing as an investigational tool, and extends the utility of {sup 14}C labeled compounds to dramatically lower levels. It is a form of isotope ratio mass spectrometry that can provide either measurements of total compound equivalents or, when coupled to separation technology such as chromatography, quantitation of specific compounds. The properties of AMS as a measurement technique are investigated here, and the parameters of method validation are shown. AMS, independent of any separation technique to which it may be coupled, is shown to be accurate, linear, precise, and robust. As the sensitivity and universality of AMS is constantly being explored and expanded, this work underpins many areas of pharmaceutical development including drug metabolism as well as absorption, distribution and excretion of pharmaceutical compounds as a fundamental step in drug development. The validation parameters for pharmaceutical analyses were examined for the accelerator mass spectrometry measurement of {sup 14}C/C ratio, independent of chemical separation procedures. The isotope ratio measurement was specific (owing to the {sup 14}C label), stable across samples storage conditions for at least one year, linear over 4 orders of magnitude with an analytical range from one tenth Modern to at least 2000 Modern (instrument specific). Further, accuracy was excellent between 1 and 3 percent while precision expressed as coefficient of variation is between 1 and 6% determined primarily by radiocarbon content and the time spent analyzing a sample. Sensitivity, expressed as LOD and LLOQ was 1 and 10 attomoles of carbon-14 (which can be expressed as compound equivalents) and for a typical small molecule labeled at 10% incorporated with {sup 14}C corresponds to 30 fg

  17. Analytical Methods for the Quantification of Histamine and Histamine Metabolites.

    Science.gov (United States)

    Bähre, Heike; Kaever, Volkhard

    2017-01-01

    The endogenous metabolite histamine (HA) is synthesized in various mammalian cells but can also be ingested from exogenous sources. It is involved in a plethora of physiological and pathophysiological processes. So far, four different HA receptors (H 1 R-H 4 R) have been described and numerous HAR antagonists have been developed. Contemporary investigations regarding the various roles of HA and its main metabolites have been hampered by the lack of highly specific and sensitive analytic methods for all of these analytes. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) is the method of choice for identification and sensitive quantification of many low-molecular weight endogenous metabolites. In this chapter, different methodological aspects of HA quantification as well as recommendations for LC-MS/MS methods suitable for analysis of HA and its main metabolites are summarized.

  18. Developments and retrospectives in Lie theory geometric and analytic methods

    CERN Document Server

    Penkov, Ivan; Wolf, Joseph

    2014-01-01

    This volume reviews and updates a prominent series of workshops in representation/Lie theory, and reflects the widespread influence of those  workshops in such areas as harmonic analysis, representation theory, differential geometry, algebraic geometry, and mathematical physics.  Many of the contributors have had leading roles in both the classical and modern developments of Lie theory and its applications. This Work, entitled Developments and Retrospectives in Lie Theory, and comprising 26 articles, is organized in two volumes: Algebraic Methods and Geometric and Analytic Methods. This is the Geometric and Analytic Methods volume. The Lie Theory Workshop series, founded by Joe Wolf and Ivan Penkov and joined shortly thereafter by Geoff Mason, has been running for over two decades. Travel to the workshops has usually been supported by the NSF, and local universities have provided hospitality. The workshop talks have been seminal in describing new perspectives in the field covering broad areas of current re...

  19. Nuclear and nuclear related analytical methods applied in environmental research

    International Nuclear Information System (INIS)

    Popescu, Ion V.; Gheboianu, Anca; Bancuta, Iulian; Cimpoca, G. V; Stihi, Claudia; Radulescu, Cristiana; Oros Calin; Frontasyeva, Marina; Petre, Marian; Dulama, Ioana; Vlaicu, G.

    2010-01-01

    Nuclear Analytical Methods can be used for research activities on environmental studies like water quality assessment, pesticide residues, global climatic change (transboundary), pollution and remediation. Heavy metal pollution is a problem associated with areas of intensive industrial activity. In this work the moss bio monitoring technique was employed to study the atmospheric deposition in Dambovita County Romania. Also, there were used complementary nuclear and atomic analytical methods: Neutron Activation Analysis (NAA), Atomic Absorption Spectrometry (AAS) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). These high sensitivity analysis methods were used to determine the chemical composition of some samples of mosses placed in different areas with different pollution industrial sources. The concentrations of Cr, Fe, Mn, Ni and Zn were determined. The concentration of Fe from the same samples was determined using all these methods and we obtained a very good agreement, in statistical limits, which demonstrate the capability of these analytical methods to be applied on a large spectrum of environmental samples with the same results. (authors)

  20. FORECASTING PILE SETTLEMENT ON CLAYSTONE USING NUMERICAL AND ANALYTICAL METHODS

    Directory of Open Access Journals (Sweden)

    Ponomarev Andrey Budimirovich

    2016-06-01

    Full Text Available In the article the problem of designing pile foundations on claystones is reviewed. The purpose of this paper is comparative analysis of the analytical and numerical methods for forecasting the settlement of piles on claystones. The following tasks were solved during the study: 1 The existing researches of pile settlement are analyzed; 2 The characteristics of experimental studies and the parameters for numerical modeling are presented, methods of field research of single piles’ operation are described; 3 Calculation of single pile settlement is performed using numerical methods in the software package Plaxis 2D and analytical method according to the requirements SP 24.13330.2011; 4 Experimental data is compared with the results of analytical and numerical calculations; 5 Basing on these results recommendations for forecasting pile settlement on claystone are presented. Much attention is paid to the calculation of pile settlement considering the impacted areas in ground space beside pile and the comparison with the results of field experiments. Basing on the obtained results, for the prediction of settlement of single pile on claystone the authors recommend using the analytical method considered in SP 24.13330.2011 with account for the impacted areas in ground space beside driven pile. In the case of forecasting the settlement of single pile on claystone by numerical methods in Plaxis 2D the authors recommend using the Hardening Soil model considering the impacted areas in ground space beside the driven pile. The analyses of the results and calculations are presented for examination and verification; therefore it is necessary to continue the research work of deep foundation at another experimental sites to improve the reliability of the calculation of pile foundation settlement. The work is of great interest for geotechnical engineers engaged in research, design and construction of pile foundations.

  1. Development and validation of an analytical method for the separation and determination of major bioactive curcuminoids in Curcuma longa rhizomes and herbal products using non-aqueous capillary electrophoresis.

    Science.gov (United States)

    Anubala, S; Sekar, R; Nagaiah, K

    2014-06-01

    A simple, fast and efficient non-aqueous capillary electrophoresis method (NACE) was developed for the simultaneous determination of three major bioactive curcuminoids (CMNs) in Curcuma longa rhizomes and its herbal products. Good separation, resolution and reproducibility were achieved with the background electrolyte (BGE) consisting a mixture of 15.0 mM sodium tetraborate and 7.4 mM sodium hydroxide (NaOH) in 2:10:15 (v/v/v) of water, 1-propanol, and methanol. The influences of background electrolyte, sodium hydroxide, water, sodium dodecyl sulfate and hydroxylpropyl-β-cyclodextrin on separations were investigated. The separation was carried out in a fused-silica capillary tube with reverse polarity. Hydrodynamic injection of 25mbar for 12s was used for injecting samples and a voltage of 28 kV was applied for separation. The ultrasonication method was used for the extraction of CMNs from the turmeric herbal products and the extract was filtered and directly injected without any further treatments. The limits of detection and quantification were less than 5.0 and 14.6 µg/ml respectively for all CMNs. The percentage recoveries for CMNs were >97.2% (%RSD, <2.62). The results obtained by the method were compared with existing spectrophotometric and HPLC methods. The related compounds in the extract did not interfere in the determination of CMNs. The proposed NACE method is better than existing chromatographic and electrophoretic methods in terms of simple electrophoretic medium, fast analysis and good resolution. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Inter-model, analytical, and experimental validation of a heat balance based residential cooling load calculation procedure

    Science.gov (United States)

    Xiao, Dongyi

    Scope and method of study. A systematic validation of the ASHRAE heat balance based residential cooling load calculation procedure (RHB) has been performed with inter-model comparison, analytical verification and experimental validation. The inter-model validation was performed using ESP-r as the reference model. The testing process was automated through parametric generation and simulation of large sets of test cases for both RHB and ESP-r. The house prototypes covered include a simple Shoebox prototype and a real 4-bedroom house prototype. An analytical verification test suite for building fabric models of whole building energy simulation programs has been developed. The test suite consists of a series of sixteen tests covering convection, conduction, solar irradiation, long-wave radiation, infiltration and ground-coupled floors. Using the test suite, a total of twelve analytical tests have been done with the RHB procedure. The experimental validation has been conducted using experimental data collected from a Cardinal Project house located in Fort Wayne, Indiana. During the diagnostic process of the experimental validation, comparisons have also been made between ESP-r simulation results and experimental data. Findings and conclusions. It is concluded RHB is acceptable as a design tool on a typical North American house. Analytical tests confirmed the underlying mechanisms for modeling basic heat transfer phenomena in building fabric. The inter-model comparison showed that the differences found between RHB and ESP-r can be traced to the differences in sub-models used by RHB and ESP-r. It also showed that the RHB-designed systems can meet the design criteria and that the RHB temperature swing option is helpful in reducing system over-sizing. The experimental validation demonstrated that the systems designed with the method will have adequate size to meet the room temperatures specified in the design, whether or not swing is utilized. However, actual system

  3. Analytical validation of an ultraviolet-visible procedure for determining lutein concentration and application to lutein-loaded nanoparticles.

    Science.gov (United States)

    Silva, Jéssica Thaís do Prado; Silva, Anderson Clayton da; Geiss, Julia Maria Tonin; de Araújo, Pedro Henrique Hermes; Becker, Daniela; Bracht, Lívia; Leimann, Fernanda Vitória; Bona, Evandro; Guerra, Gustavo Petri; Gonçalves, Odinei Hess

    2017-09-01

    Lutein is a carotenoid presenting known anti-inflammatory and antioxidant properties. Lutein-rich diets have been associated with neurological improvement as well as reduction of the risk of vision loss due to Age-Related Macular Degeneration (AMD). Micro and nanoencapsulation have demonstrated to be effective techniques in protecting lutein against degradation and also in improving its bioavailability. However, actual lutein concentration inside the capsules and encapsulation efficiency are key parameters that must be precisely known when designing in vitro and in vivo tests. In this work an analytical procedure was validated for the determination of the actual lutein content in zein nanoparticles using ultraviolet-visible spectroscopy. Method validation followed the International Conference on Harmonisation (ICH) guidelines which evaluate linearity, detection limit, quantification limit, accuracy and precision. The validated methodology was applied to characterize lutein-loaded nanoparticles. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Customizing computational methods for visual analytics with big data.

    Science.gov (United States)

    Choo, Jaegul; Park, Haesun

    2013-01-01

    The volume of available data has been growing exponentially, increasing data problem's complexity and obscurity. In response, visual analytics (VA) has gained attention, yet its solutions haven't scaled well for big data. Computational methods can improve VA's scalability by giving users compact, meaningful information about the input data. However, the significant computation time these methods require hinders real-time interactive visualization of big data. By addressing crucial discrepancies between these methods and VA regarding precision and convergence, researchers have proposed ways to customize them for VA. These approaches, which include low-precision computation and iteration-level interactive visualization, ensure real-time interactive VA for big data.

  5. Ethical leadership: meta-analytic evidence of criterion-related and incremental validity.

    Science.gov (United States)

    Ng, Thomas W H; Feldman, Daniel C

    2015-05-01

    This study examines the criterion-related and incremental validity of ethical leadership (EL) with meta-analytic data. Across 101 samples published over the last 15 years (N = 29,620), we observed that EL demonstrated acceptable criterion-related validity with variables that tap followers' job attitudes, job performance, and evaluations of their leaders. Further, followers' trust in the leader mediated the relationships of EL with job attitudes and performance. In terms of incremental validity, we found that EL significantly, albeit weakly in some cases, predicted task performance, citizenship behavior, and counterproductive work behavior-even after controlling for the effects of such variables as transformational leadership, use of contingent rewards, management by exception, interactional fairness, and destructive leadership. The article concludes with a discussion of ways to strengthen the incremental validity of EL. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  6. Analytical method comparisons for the accurate determination of PCBs in sediments

    Energy Technology Data Exchange (ETDEWEB)

    Numata, M.; Yarita, T.; Aoyagi, Y.; Yamazaki, M.; Takatsu, A. [National Metrology Institute of Japan, Tsukuba (Japan)

    2004-09-15

    National Metrology Institute of Japan in National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) has been developing several matrix reference materials, for example, sediments, water and biological tissues, for the determinations of heavy metals and organometallic compounds. The matrix compositions of those certified reference materials (CRMs) are similar to compositions of actual samples, and those are useful for validating analytical procedures. ''Primary methods of measurements'' are essential to obtain accurate and SI-traceable certified values in the reference materials, because the methods have the highest quality of measurement. However, inappropriate analytical operations, such as incomplete extraction of analytes or crosscontamination during analytical procedures, will cause error of analytical results, even if one of the primary methods, isotope-dilution, is utilized. To avoid possible procedural bias for the certification of reference materials, we employ more than two analytical methods which have been optimized beforehand. Because the accurate determination of trace POPs in the environment is important to evaluate their risk, reliable CRMs are required by environmental chemists. Therefore, we have also been preparing matrix CRMs for the determination of POPs. To establish accurate analytical procedures for the certification of POPs, extraction is one of the critical steps as described above. In general, conventional extraction techniques for the determination of POPs, such as Soxhlet extraction (SOX) and saponification (SAP), have been characterized well, and introduced as official methods for environmental analysis. On the other hand, emerging techniques, such as microwave-assisted extraction (MAE), pressurized fluid extraction (PFE) and supercritical fluid extraction (SFE), give higher recovery yields of analytes with relatively short extraction time and small amount of solvent, by reasons of the high

  7. Spacecraft early design validation using formal methods

    International Nuclear Information System (INIS)

    Bozzano, Marco; Cimatti, Alessandro; Katoen, Joost-Pieter; Katsaros, Panagiotis; Mokos, Konstantinos; Nguyen, Viet Yen; Noll, Thomas; Postma, Bart; Roveri, Marco

    2014-01-01

    The size and complexity of software in spacecraft is increasing exponentially, and this trend complicates its validation within the context of the overall spacecraft system. Current validation methods are labor-intensive as they rely on manual analysis, review and inspection. For future space missions, we developed – with challenging requirements from the European space industry – a novel modeling language and toolset for a (semi-)automated validation approach. Our modeling language is a dialect of AADL and enables engineers to express the system, the software, and their reliability aspects. The COMPASS toolset utilizes state-of-the-art model checking techniques, both qualitative and probabilistic, for the analysis of requirements related to functional correctness, safety, dependability and performance. Several pilot projects have been performed by industry, with two of them having focused on the system-level of a satellite platform in development. Our efforts resulted in a significant advancement of validating spacecraft designs from several perspectives, using a single integrated system model. The associated technology readiness level increased from level 1 (basic concepts and ideas) to early level 4 (laboratory-tested)

  8. Validation of pestice multi residue analysis method on cucumber

    International Nuclear Information System (INIS)

    2011-01-01

    In this study we aimed to validate the method of multi pesticide residue analysis on cucumber. Before real sample injection, system suitability test was performed in gas chromatography (GC). For this purpose, a sensitive pesticide mixture was used for GC-NPD and estimated the performance parameters such as number of effective theoretical plates, resolution factor, asymmetry, tailing and selectivity. It was detected that the system was suitable for calibration and sample injection. Samples were fortified at the level of 0.02, 0.2, 0.8 and 1 mg/kg with mixture of dichlorvos, malathion and chloropyrifos pesticides. In the fortification step 1 4C-carbaryl was also added on homogenized analytical portions to make use of 1 4C labelled pesticides for the determining extraction efficiency. Then the basic analytical process, such as ethyl acetate extraction, filtration, evaporation and cleanup, were performed. The GPC calibration using 1 4C- carbaryl and fortification mixture (dichlorvos, malathion and chloropyrifos) showed that pesticide fraction come through the column between the 8-23 ml fractions. The recovery of 1 4C-carbaryl after the extraction and cleanup step were 92.63-111.73 % and 74.83-102.22 %, respectively. The stability of pesticides during analysis is an important factor. In this study, stability test was performed including matrix effect. Our calculation and t test results showed that above mentioned pesticides were not stabile during sample processing in our laboratory conditions and it was found that sample comminution with dry ice may improve stability. In the other part of the study, 1 4C-chloropyrifos was used to determine homogeneity of analytical portions taken from laboratory samples. Use of 1 4C labelled pesticides allows us for quick quantification analyte, even with out clean-up. The analytical results show that after sample processing with waring blender, analytical portions were homogenous. Sample processing uncertainty depending on quantity of

  9. Analytical methods for determination of terbinafine hydrochloride in pharmaceuticals and biological materials

    Directory of Open Access Journals (Sweden)

    Basavaiah Kanakapura

    2016-06-01

    Full Text Available Terbinafine is a new powerful antifungal agent indicated for both oral and topical treatment of mycosessince. It is highly effective in the treatment of determatomycoses. The chemical and pharmaceutical analysis of the drug requires effective analytical methods for quality control and pharmacodynamic and pharmacokinetic studies. Ever since it was introduced as an effective antifungal agent, many methods have been developed and validated for its assay in pharmaceuticals and biological materials. This article reviews the various methods reported during the last 25 years.

  10. Validation of the quality control methods for active ingredients of Fungirex cream

    International Nuclear Information System (INIS)

    Perez Navarro, Maikel; Rodriguez Hernandez, Yaslenis; Suarez Perez, Yania

    2014-01-01

    Fungirex cream is a two-drug product, that is, undecylenic acid and zinc undecylenate over a suitable basis. Since this is a product not documented in the official monographs of the pharmacopoeia, simple analytical methods were suggested for quantitation of analytes of interest in the cream, which are useful for release of newly prepared cream batches. To validate two volumetric methods for the quality control of active ingredients in Fungirex cream

  11. A Process Analytical Technology (PAT) approach to control a new API manufacturing process: development, validation and implementation.

    Science.gov (United States)

    Schaefer, Cédric; Clicq, David; Lecomte, Clémence; Merschaert, Alain; Norrant, Edith; Fotiadu, Frédéric

    2014-03-01

    Pharmaceutical companies are progressively adopting and introducing Process Analytical Technology (PAT) and Quality-by-Design (QbD) concepts promoted by the regulatory agencies, aiming the building of the quality directly into the product by combining thorough scientific understanding and quality risk management. An analytical method based on near infrared (NIR) spectroscopy was developed as a PAT tool to control on-line an API (active pharmaceutical ingredient) manufacturing crystallization step during which the API and residual solvent contents need to be precisely determined to reach the predefined seeding point. An original methodology based on the QbD principles was designed to conduct the development and validation of the NIR method and to ensure that it is fitted for its intended use. On this basis, Partial least squares (PLS) models were developed and optimized using chemometrics methods. The method was fully validated according to the ICH Q2(R1) guideline and using the accuracy profile approach. The dosing ranges were evaluated to 9.0-12.0% w/w for the API and 0.18-1.50% w/w for the residual methanol. As by nature the variability of the sampling method and the reference method are included in the variability obtained for the NIR method during the validation phase, a real-time process monitoring exercise was performed to prove its fit for purpose. The implementation of this in-process control (IPC) method on the industrial plant from the launch of the new API synthesis process will enable automatic control of the final crystallization step in order to ensure a predefined quality level of the API. In addition, several valuable benefits are expected including reduction of the process time, suppression of a rather difficult sampling and tedious off-line analyses. © 2013 Published by Elsevier B.V.

  12. Benchmark Comparison of Cloud Analytics Methods Applied to Earth Observations

    Science.gov (United States)

    Lynnes, Chris; Little, Mike; Huang, Thomas; Jacob, Joseph; Yang, Phil; Kuo, Kwo-Sen

    2016-01-01

    Cloud computing has the potential to bring high performance computing capabilities to the average science researcher. However, in order to take full advantage of cloud capabilities, the science data used in the analysis must often be reorganized. This typically involves sharding the data across multiple nodes to enable relatively fine-grained parallelism. This can be either via cloud-based file systems or cloud-enabled databases such as Cassandra, Rasdaman or SciDB. Since storing an extra copy of data leads to increased cost and data management complexity, NASA is interested in determining the benefits and costs of various cloud analytics methods for real Earth Observation cases. Accordingly, NASA's Earth Science Technology Office and Earth Science Data and Information Systems project have teamed with cloud analytics practitioners to run a benchmark comparison on cloud analytics methods using the same input data and analysis algorithms. We have particularly looked at analysis algorithms that work over long time series, because these are particularly intractable for many Earth Observation datasets which typically store data with one or just a few time steps per file. This post will present side-by-side cost and performance results for several common Earth observation analysis operations.

  13. Benchmark Comparison of Cloud Analytics Methods Applied to Earth Observations

    Science.gov (United States)

    Lynnes, C.; Little, M. M.; Huang, T.; Jacob, J. C.; Yang, C. P.; Kuo, K. S.

    2016-12-01

    Cloud computing has the potential to bring high performance computing capabilities to the average science researcher. However, in order to take full advantage of cloud capabilities, the science data used in the analysis must often be reorganized. This typically involves sharding the data across multiple nodes to enable relatively fine-grained parallelism. This can be either via cloud-based filesystems or cloud-enabled databases such as Cassandra, Rasdaman or SciDB. Since storing an extra copy of data leads to increased cost and data management complexity, NASA is interested in determining the benefits and costs of various cloud analytics methods for real Earth Observation cases. Accordingly, NASA's Earth Science Technology Office and Earth Science Data and Information Systems project have teamed with cloud analytics practitioners to run a benchmark comparison on cloud analytics methods using the same input data and analysis algorithms. We have particularly looked at analysis algorithms that work over long time series, because these are particularly intractable for many Earth Observation datasets which typically store data with one or just a few time steps per file. This post will present side-by-side cost and performance results for several common Earth observation analysis operations.

  14. Analytical method to determine flexoelectric coupling coefficient at nanoscale

    Science.gov (United States)

    Zhou, Hao; Pei, Yongmao; Hong, Jiawang; Fang, Daining

    2016-03-01

    Flexoelectricity is defined as the coupling between the strain gradient and polarization, which is expected to be remarkable at nanoscale. However, measuring the flexoelectricity at nanoscale is challenging. In the present work, an analytical method for measuring the flexoelectric coupling coefficient based on nanocompression technique is proposed. It is found that the flexoelectricity can induce stiffness softening of the dielectric nano-cone-frustum. This phenomenon becomes more significant when the sample size decreases or the half cone angle increases. This method avoids measuring the electric polarization or current at nanoscale with dynamical loading, which can be beneficial to the flexoelectric measurement at nanoscale and design of flexoelectric nanodevices.

  15. Simplified Analytical Method for Optimized Initial Shape Analysis of Self-Anchored Suspension Bridges and Its Verification

    Directory of Open Access Journals (Sweden)

    Myung-Rag Jung

    2015-01-01

    Full Text Available A simplified analytical method providing accurate unstrained lengths of all structural elements is proposed to find the optimized initial state of self-anchored suspension bridges under dead loads. For this, equilibrium equations of the main girder and the main cable system are derived and solved by evaluating the self-weights of cable members using unstrained cable lengths and iteratively updating both the horizontal tension component and the vertical profile of the main cable. Furthermore, to demonstrate the validity of the simplified analytical method, the unstrained element length method (ULM is applied to suspension bridge models based on the unstressed lengths of both cable and frame members calculated from the analytical method. Through numerical examples, it is demonstrated that the proposed analytical method can indeed provide an optimized initial solution by showing that both the simplified method and the nonlinear FE procedure lead to practically identical initial configurations with only localized small bending moment distributions.

  16. Comparison of analytical methods for calculation of wind loads

    Science.gov (United States)

    Minderman, Donald J.; Schultz, Larry L.

    1989-01-01

    The following analysis is a comparison of analytical methods for calculation of wind load pressures. The analytical methods specified in ASCE Paper No. 3269, ANSI A58.1-1982, the Standard Building Code, and the Uniform Building Code were analyzed using various hurricane speeds to determine the differences in the calculated results. The winds used for the analysis ranged from 100 mph to 125 mph and applied inland from the shoreline of a large open body of water (i.e., an enormous lake or the ocean) a distance of 1500 feet or ten times the height of the building or structure considered. For a building or structure less than or equal to 250 feet in height acted upon by a wind greater than or equal to 115 mph, it was determined that the method specified in ANSI A58.1-1982 calculates a larger wind load pressure than the other methods. For a building or structure between 250 feet and 500 feet tall acted upon by a wind rangind from 100 mph to 110 mph, there is no clear choice of which method to use; for these cases, factors that must be considered are the steady-state or peak wind velocity, the geographic location, the distance from a large open body of water, and the expected design life and its risk factor.

  17. Analytical Methods for Mycotoxin Detection in Southeast Asian Nations (ASEAN).

    Science.gov (United States)

    Lim, Chee Wei; Chung, Gerald; Chan, Sheot Harn

    2017-10-03

    Aflatoxins B 1 (AFB 1 ) and B₂ (AFB₂) and G 1 and G₂ remain the top mycotoxins routinely analyzed and monitored by Association of Southeast Asian Nations (ASEAN) national laboratories primarily for food safety regulation in the major food commodities, nuts and spices. LC tandem fluorescence detection (LC–fluorescence) represents a current mainstream analytical method, with a progressive migration to a primary method by LC tandem MS (MS/MS) for the next half decade. Annual proficiency testing (PT) is conducted by ASEAN Food Reference Laboratories (AFRLs) for mycotoxin testing as part of capability building in national laboratories, with the scope of PT materials spanning from naturally mycotoxin-contaminated spices and nuts in the early 2010s to the recent contamination of corn flour in 2017 for total aflatoxin assay development. The merits of the mainstream LC–fluorescence method are witnessed by a significant improvement ( P < 0.05) in PT z -score passing rates (≤2) from 11.8 to 79.2% for AFB 1 , 23.5 to 83.3% for AFB₂, and 23.5 to 79.2% for total aflatoxins in the last 5 years. This paper discusses the journey of ASEAN national laboratories in analytical testing through AFRLs, and the progressive collective adoption of a multimycotoxin LC-MS/MS method aided by an isotopic dilution assay as a future primary method for safer food commodities.

  18. Validación de método analítico para el control de la calidad de vitamina B12 10 000 inyección Validation of analytical method for quality control of B12 Vitamin-10 000 injection

    Directory of Open Access Journals (Sweden)

    Martha Botet García

    2009-12-01

    Full Text Available Se validó el método analítico reportado en la Farmacopea de los Estados Unidos, para el control de la calidad de vitamina B12 10 000 U (cianocobalamina inyectable, por espectrofotometría ultravioleta, por ser este un método más sencillo, económico y que permite controlar la calidad del producto terminado. La curva de calibración se realizó en el intervalo de 60 al 140 %, donde fue lineal con un coeficiente de correlación igual a 0,9999; la prueba estadística para el intercepto y la pendiente se consideró no significativa. Se obtuvo un recobrado del 99,97 % en el intervalo de concentraciones estudiado, y las pruebas de Cochran (G y Student (t resultaron no significativas. El coeficiente de variación en el estudio de la repetibilidad fue igual a 0,59 % para las 6 réplicas ensayadas, mientras que en los análisis de la precisión intermedia las pruebas de Fischer y Student no significativas. El método analítico resultó lineal, preciso, específico y exacto en el intervalo de concentraciones estudiadas.Analytical method reported by USA Pharmacopeia was validated for quality control of injectable B12 Vitamin (10 000 U by UV spectrophotometry because this is a simpler and low-cost method allowing quality control of finished product. Calibration curve was graphed at 60 to 140 % interval, where it was linear with a correlation coefficient similar to 0, 9999; statistical test for interception and slope was considered non-significant. There was a recovery of 99.7 % in study concentrations interval where the Cochran (G and Student(t test were not significant too. Variation coefficient in repetition study was similar to 0.59 % for the 6 assayed replies, whereas in intermediate precision analysis, the Fisher and Student tests were not significant. Analytical method was linear, precise, specific and exact in study concentrations interval.

  19. Validación del método analítico para el control de la calidad y estudio de estabilidad de ketotifeno colirio 0,025 % Validation of analytical method to quality control and the stability study of 0.025 % eyedrops Ketotiphen

    Directory of Open Access Journals (Sweden)

    Yenilen Troche Concepción

    2010-09-01

    Full Text Available El colirio de ketotifeno se indica para aliviar los signos y síntomas de las conjuntivitis alérgicas, por ser este un potente antihistamínico H1 que muestra cierta capacidad para inhibir la liberación de histamina y otros mediadores en mastocitos. En este trabajo se desarrolló y validó un método analítico por cromatografía líquida de alta resolución, para el control de la calidad y los estudios de estabilidad del ketotifeno colirio 0,025 %. El método se basó en la separación del principio activo a través una columna cromatográfica Lichrosorb RP-18 (5 µm (250 x 4 mm, con detección ultravioleta a 296 nm, para lo cual se empleó una fase móvil compuesta por una mezcla desgasificada de metanol:buffer fosfato (75:25; pH 8,5 y se le añadió 1 mL de isopropanol por cada 1 000 mL de la mezcla anterior, con una velocidad de flujo de 1,2 mL/min. El método analítico resultó lineal, preciso, específico y exacto en el intervalo de concentraciones estudiadas.The Ketotiphen eyedrop is prescribed to relief the signs and symptoms of allergic conjunctivitis due to its potent H1 antihistaminic effect showing some ability to inhibit the histamine release and other mediators in cases of mastocytosis. The aim of present paper was to develop and validate an analytical method for the high-performance liquid chromatography, to quality control and the stability studies of 0.025 % eyedrop Ketotiphen. Method was based on active principle separation by means of a Lichrosorb RP-18 (5 µm (250 x 4 mm, with UV detection to 296 nm using a mobile phase including a non-gasified mixture of methanol:buffer-phosphate (75:25; pH 8.5 adding 1 mL of Isopropanol by each 1 000 mL of the previous mixture at a 1.2 mL/min flow velocity. The analytical method was linear, accurate, specific and exact during the study concentrations.

  20. O enfoque da metrologia química em análises toxicológicas na atividade turfística: validação de método analítico para determinação de cafeína em matrizes biológicas The chemical metrology approach for toxicological analysis in horseracing: validation of an analytical method for the determination of caffeine in biological matrices

    Directory of Open Access Journals (Sweden)

    India Maria H. de Lima

    2007-01-01

    Full Text Available This paper proposes an alternate method to detect forbidden doping substances present in biological matrices of horseracing. The method was fully validated for caffeine, identified as the most frequent forbidden substance in the analysis conducted by the Antidoping Laboratory of the Brazilian Jockey Club, which adopts a zero threshold limit according to national and international horseracing practices. The metrological reliability of the method applied to toxicological analysis in biological matrices is discussed. Although the analytical method proposed for detection of a zero threshold level of the doping substance is qualitative, it was validated for the determination of the limiting value (also known as quantification limit value introducing a criterion that prevents the issuing of incorrect results ("false-positives" and "false-negatives".

  1. A preliminary investigation of PSA validation methods

    International Nuclear Information System (INIS)

    Unwin, S.D.

    1995-09-01

    This document has been prepared to support the initial phase of the Atomic Energy Control Board's program to review and evaluate Probabilistic Safety Assessment (PSA) studies conducted by nuclear generating station designers and licensees. The document provides (1) a review of current and prospective applications of PSA technology in the Canadian nuclear power industry; (2) an assessment of existing practices and techniques for the review or risk and hazard identification studies in the international nuclear power sector and other technological sectors; and (3) proposed analytical framework in which to develop systematic techniques for the scrutiny and evaluation of a PSA model. These frameworks are based on consideration of the mathematical structure of a PSA model and are intended to facilitate the development of methods to evaluate a model relative to intended end-uses. (author). 34 refs., 10 tabs., 3 figs

  2. An interactive website for analytical method comparison and bias estimation.

    Science.gov (United States)

    Bahar, Burak; Tuncel, Ayse F; Holmes, Earle W; Holmes, Daniel T

    2017-12-01

    Regulatory standards mandate laboratories to perform studies to ensure accuracy and reliability of their test results. Method comparison and bias estimation are important components of these studies. We developed an interactive website for evaluating the relative performance of two analytical methods using R programming language tools. The website can be accessed at https://bahar.shinyapps.io/method_compare/. The site has an easy-to-use interface that allows both copy-pasting and manual entry of data. It also allows selection of a regression model and creation of regression and difference plots. Available regression models include Ordinary Least Squares, Weighted-Ordinary Least Squares, Deming, Weighted-Deming, Passing-Bablok and Passing-Bablok for large datasets. The server processes the data and generates downloadable reports in PDF or HTML format. Our website provides clinical laboratories a practical way to assess the relative performance of two analytical methods. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  3. A nonlinear analytic function expansion nodal method for transient calculations

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Han Gyn; Park, Sang Yoon; Cho, Byung Oh; Zee, Sung Quun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    The nonlinear analytic function expansion nodal (AFEN) method is applied to the solution of the time-dependent neutron diffusion equation. Since the AFEN method requires both the particular solution and the homogeneous solution to the transient fixed source problem, the derivation of the solution method is focused on finding the particular solution efficiently. To avoid complicated particular solutions, the source distribution is approximated by quadratic polynomials and the transient source is constructed such that the error due to the quadratic approximation is minimized, In addition, this paper presents a new two-node solution scheme that is derived by imposing the constraint of current continuity at the interface corner points. The method is verified through a series of application to the NEACRP PWR rod ejection benchmark problems. 6 refs., 2 figs., 1 tab. (Author)

  4. Analytical methods for toxic gases from thermal degradation of polymers

    Science.gov (United States)

    Hsu, M.-T. S.

    1977-01-01

    Toxic gases evolved from the thermal oxidative degradation of synthetic or natural polymers in small laboratory chambers or in large scale fire tests are measured by several different analytical methods. Gas detector tubes are used for fast on-site detection of suspect toxic gases. The infrared spectroscopic method is an excellent qualitative and quantitative analysis for some toxic gases. Permanent gases such as carbon monoxide, carbon dioxide, methane and ethylene, can be quantitatively determined by gas chromatography. Highly toxic and corrosive gases such as nitrogen oxides, hydrogen cyanide, hydrogen fluoride, hydrogen chloride and sulfur dioxide should be passed into a scrubbing solution for subsequent analysis by either specific ion electrodes or spectrophotometric methods. Low-concentration toxic organic vapors can be concentrated in a cold trap and then analyzed by gas chromatography and mass spectrometry. The limitations of different methods are discussed.

  5. Reducing waste generation and radiation exposure by analytical method modification

    Energy Technology Data Exchange (ETDEWEB)

    Ekechukwu, A.A.

    1996-10-01

    The primary goal of an analytical support laboratory has traditionally been to provide accurate data in a timely and cost effective fashion. Added to this goal is now the need to provide the same high quality data while generating as little waste as possible. At the Savannah River Technology Center (SRTC), we have modified and reengineered several methods to decrease generated waste and hence reduce radiation exposure. These method changes involved improving detection limits (which decreased the amount of sample required for analysis), decreasing reaction and analysis time, decreasing the size of experimental set-ups, recycling spent solvent and reagents, and replacing some methods. These changes had the additional benefits of reducing employee radiation exposure and exposure to hazardous chemicals. In all cases, the precision, accuracy, and detection limits were equal to or better than the replaced method. Most of the changes required little or no expenditure of funds. This paper describes these changes and discusses some of their applications.

  6. ANALYTICAL METHODS FOR KINETIC STUDIES OF BIOLOGICAL INTERACTIONS: A REVIEW

    Science.gov (United States)

    Zheng, Xiwei; Bi, Cong; Li, Zhao; Podariu, Maria; Hage, David S.

    2015-01-01

    The rates at which biological interactions occur can provide important information concerning the mechanism and behavior of these processes in living systems. This review discusses several analytical methods that can be used to examine the kinetics of biological interactions. These techniques include common or traditional methods such as stopped-flow analysis and surface plasmon resonance spectroscopy, as well as alternative methods based on affinity chromatography and capillary electrophoresis. The general principles and theory behind these approaches are examined, and it is shown how each technique can be utilized to provide information on the kinetics of biological interactions. Examples of applications are also given for each method. In addition, a discussion is provided on the relative advantages or potential limitations of each technique regarding its use in kinetic studies. PMID:25700721

  7. Selectivity in analytical chemistry: two interpretations for univariate methods.

    Science.gov (United States)

    Dorkó, Zsanett; Verbić, Tatjana; Horvai, George

    2015-01-01

    Selectivity is extremely important in analytical chemistry but its definition is elusive despite continued efforts by professional organizations and individual scientists. This paper shows that the existing selectivity concepts for univariate analytical methods broadly fall in two classes: selectivity concepts based on measurement error and concepts based on response surfaces (the response surface being the 3D plot of the univariate signal as a function of analyte and interferent concentration, respectively). The strengths and weaknesses of the different definitions are analyzed and contradictions between them unveiled. The error based selectivity is very general and very safe but its application to a range of samples (as opposed to a single sample) requires the knowledge of some constraint about the possible sample compositions. The selectivity concepts based on the response surface are easily applied to linear response surfaces but may lead to difficulties and counterintuitive results when applied to nonlinear response surfaces. A particular advantage of this class of selectivity is that with linear response surfaces it can provide a concentration independent measure of selectivity. In contrast, the error based selectivity concept allows only yes/no type decision about selectivity. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. The fitness for purpose of analytical methods applied to fluorimetric uranium determination in water matrix

    International Nuclear Information System (INIS)

    Grinman, Ana; Giustina, Daniel; Mondini, Julia; Diodat, Jorge

    2008-01-01

    Full text: This paper describes the steps which should be followed by a laboratory in order to validate the fluorimetric method for natural uranium in water matrix. The validation of an analytical method is a necessary requirement prior accreditation under Standard norm ISO/IEC 17025, of a non normalized method. Different analytical techniques differ in a sort of variables to be validated. Depending on the chemical process, measurement technique, matrix type, data fitting and measurement efficiency, a laboratory must set up experiments to verify reliability of data, through the application of several statistical tests and by participating in Quality Programs (QP) organized by reference laboratories such as the National Institute of Standards and Technology (NIST), National Physics Laboratory (NPL), or Environmental Measurements Laboratory (EML). However, the participation in QP not only involves international reference laboratories, but also, the national ones which are able to prove proficiency to the Argentinean Accreditation Board. The parameters that the ARN laboratory had to validate in the fluorimetric method to fit in accordance with Eurachem guide and IUPAC definitions, are: Detection Limit, Quantification Limit, Precision, Intra laboratory Precision, Reproducibility Limit, Repeatability Limit, Linear Range and Robustness. Assays to fit the above parameters were designed on the bases of statistics requirements, and a detailed data treatment is presented together with the respective tests in order to show the parameters validated. As a final conclusion, the uranium determination by fluorimetry is a reliable method for direct measurement to meet radioprotection requirements in water matrix, within its linear range which is fixed every time a calibration is carried out at the beginning of the analysis. The detection limit ( depending on blank standard deviation and slope) varies between 3 ug U and 5 ug U which yields minimum detectable concentrations (MDC) of

  9. Toward a quality guide to facilitate the transference of analytical methods from research to testing laboratories: a case study.

    Science.gov (United States)

    Bisetty, Krisnha; Gumede, Njabulo Joyfull; Escuder-Gilabert, Laura; Sagrado, Salvador

    2009-01-01

    At present, there is no single viewpoint that defines QA strategies in analytical chemistry. On the other hand, there are no unique protocols defining a set of analytical tasks and decision criteria to be performed during the method development phase (e.g., by a single research laboratory) in order to facilitate the transference to the testing laboratories intending to adapt, validate, and routinely use this method. This study proposes general criteria, a priori valid for any developed method, recommended as a provisional quality guide containing the minimum internal tasks necessary to publish new analytical method results. As an application, the selection of some basic internal quality tasks and the corresponding accepted criteria are adapted to a concrete case study: indirect differential pulse polarographic determination of nitrate in water samples according to European Commission requisites. Extra tasks to be performed by testing laboratories are also outlined.

  10. Validación del método analítico para el control de la calidad y estudio de estabilidad de fenilefrina 10 % colirio Validation of an analytical method for quality control and stability study of 10 % Phenylephrine eyedrops

    Directory of Open Access Journals (Sweden)

    Raiza Monteagudo Licea

    2010-12-01

    Full Text Available La fenilefrina se emplea como midriático en exámenes de ojos y otros procedimientos oftálmicos. Se utiliza como vasoconstrictor con anestésicos locales. En este trabajo se validó un método analítico por cromatografía líquida de alta resolución para el control de la calidad y los estudios de estabilidad de la fenilefrina 10 % colirio. El método se basó en la separación del principio activo a través una columna cromatográfica Lichrosorb RP-18 (5 µm (250 x 4 mm, con detección ultravioleta a 280 nm, para lo cual se empleó una fase móvil compuesta por una mezcla desgasificada de metanol:agua destilada (1:1, con 1,1 g de 1-octanosulfonato de sodio por litro ajustado a pH 3,0 con ácido fosfórico, con una velocidad de flujo de 1,0 mL/min. El método analítico resultó lineal, preciso, específico y exacto en el intervalo de concentraciones estudiadas.Phenylephrine is used like mydiatric in eye examinations and other ophthalmic procedures. It is used as vasoconstrictor with local anesthetic agents. In present paper a high ressolution liquid chromatography analytical method was validated to quality control and stability studies of 10 % Phenylephrine (eyedrops. Mathod was based in separation of active principle through a Lichrosorb RO-18 (5 µm (250 x 4 mm chromatography column with UV detection at 280 nm using a mobile phase composed by a non-gasified mixture of methanol distilled water (1:1 with 1.1 g of 1-sodium octane-sulphonate by liter adjusted to pH 3,0 with phosphoric acid at a flow speed of 1.0 mL/min. Analytical method was linear, accuracy, specific and exact in the interval of study concentrations.

  11. The combination of four analytical methods to explore skeletal muscle metabolomics: Better coverage of metabolic pathways or a marketing argument?

    Science.gov (United States)

    Bruno, C; Patin, F; Bocca, C; Nadal-Desbarats, L; Bonnier, F; Reynier, P; Emond, P; Vourc'h, P; Joseph-Delafont, K; Corcia, P; Andres, C R; Blasco, H

    2018-01-30

    Metabolomics is an emerging science based on diverse high throughput methods that are rapidly evolving to improve metabolic coverage of biological fluids and tissues. Technical progress has led researchers to combine several analytical methods without reporting the impact on metabolic coverage of such a strategy. The objective of our study was to develop and validate several analytical techniques (mass spectrometry coupled to gas or liquid chromatography and nuclear magnetic resonance) for the metabolomic analysis of small muscle samples and evaluate the impact of combining methods for more exhaustive metabolite covering. We evaluated the muscle metabolome from the same pool of mouse muscle samples after 2 metabolite extraction protocols. Four analytical methods were used: targeted flow injection analysis coupled with mass spectrometry (FIA-MS/MS), gas chromatography coupled with mass spectrometry (GC-MS), liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS), and nuclear magnetic resonance (NMR) analysis. We evaluated the global variability of each compound i.e., analytical (from quality controls) and extraction variability (from muscle extracts). We determined the best extraction method and we reported the common and distinct metabolites identified based on the number and identity of the compounds detected with low analytical variability (variation coefficientmass spectrometry methods and nuclear magnetic resonance to explore muscle samples. This study reports the validation of several analytical methods, based on nuclear magnetic resonance and several mass spectrometry methods, to explore the muscle metabolome from a small amount of tissue, comparable to that obtained during a clinical trial. The combination of several techniques may be relevant for the exploration of muscle metabolism, with acceptable analytical variability and overlap between methods However, the difficult and time-consuming data pre-processing, processing, and

  12. Analytical method for thermal stress analysis of plasma facing materials

    International Nuclear Information System (INIS)

    You, J.H.; Bolt, H.

    2001-01-01

    The thermo-mechanical response of plasma facing materials (PFMs) to heat loads from the fusion plasma is one of the crucial issues in fusion technology. In this work, a fully analytical description of the thermal stress distribution in armour tiles of plasma facing components is presented which is expected to occur under typical high heat flux (HHF) loads. The method of stress superposition is applied considering the temperature gradient and thermal expansion mismatch. Several combinations of PFMs and heat sink metals are analysed and compared. In the framework of the present theoretical model, plastic flow and the effect of residual stress can be quantitatively assessed. Possible failure features are discussed

  13. Analytical method for thermal stress analysis of plasma facing materials

    Science.gov (United States)

    You, J. H.; Bolt, H.

    2001-10-01

    The thermo-mechanical response of plasma facing materials (PFMs) to heat loads from the fusion plasma is one of the crucial issues in fusion technology. In this work, a fully analytical description of the thermal stress distribution in armour tiles of plasma facing components is presented which is expected to occur under typical high heat flux (HHF) loads. The method of stress superposition is applied considering the temperature gradient and thermal expansion mismatch. Several combinations of PFMs and heat sink metals are analysed and compared. In the framework of the present theoretical model, plastic flow and the effect of residual stress can be quantitatively assessed. Possible failure features are discussed.

  14. Higher geometry an introduction to advanced methods in analytic geometry

    CERN Document Server

    Woods, Frederick S

    2005-01-01

    For students of mathematics with a sound background in analytic geometry and some knowledge of determinants, this volume has long been among the best available expositions of advanced work on projective and algebraic geometry. Developed from Professor Woods' lectures at the Massachusetts Institute of Technology, it bridges the gap between intermediate studies in the field and highly specialized works.With exceptional thoroughness, it presents the most important general concepts and methods of advanced algebraic geometry (as distinguished from differential geometry). It offers a thorough study

  15. Cleaning validation of ofloxacin on pharmaceutical manufacturing equipment and validation of desired HPLC method.

    Science.gov (United States)

    Arayne, M Saeed; Sultana, Najma; Sajid, S Shahnawaz; Ali, S Shahid

    2008-01-01

    Inadequate cleaning of a pharmaceutical manufacturing plant or inadequate purging of the individual pieces of equipment used in multi-product manufacturing or equipment not dedicated to individual products may lead to contamination of the next batch of pharmaceutics manufactured using the same equipment. Challenges for cleaning validation are encountered especially when developing sensitive analytical methods capable of detecting traces of active pharmaceutical ingredients that are likely to remain on the surface of the pharmaceutical equipment after cleaning. A method's inability to detect some residuals could mean that either the method is not sensitive enough to the residue in question or the sampling procedure is inadequate. A sensitive and reproducible reversed-phase, high-performance liquid chromatographic method was developed for the determination of ofloxacin in swab samples. The method for determining ofloxacin residues on manufacturing equipment surfaces was validated in regard to precision, linearity, accuracy, specificity, limit of quantification, and percent recovery from the equipment surface, as well as the stability of a potential contaminant in a cleaning validation process. The active compound was selectively quantified in a sample matrix and swab material in amounts as low as 0.55 ng/mL. The swabbing procedure using cotton swabs was validated. A mean recovery from stainless steel plate of close to 85% was obtained. Chromatography was carried out on a pre-packed Merck (Dermstadt, Germany) Lichrospher model 100 Rp-18 (5.0 microm, 250 mm X 4.0 mm) column using a mixture of sodium lauryl sulfate (0.024% aqueous solution), acetonitrile, and glacial acetic acid (500:480:20,v/v) as the mobile phase at a flow rate of 1.5 mL/min with a column temperature of 35 degrees C and 294 nm detection. The assay was linear over the concentration range of 2 ng/mL to 2000 ng/mL (R approximately 0.99998). The method was validated for accuracy and precision. The

  16. Analytical method of spectra calculations in the Bargmann representation

    Energy Technology Data Exchange (ETDEWEB)

    Maciejewski, Andrzej J., E-mail: maciejka@astro.ia.uz.zgora.pl [J. Kepler Institute of Astronomy, University of Zielona Góra, Licealna 9, PL-65-417 Zielona Góra (Poland); Przybylska, Maria, E-mail: M.Przybylska@if.uz.zgora.pl [Institute of Physics, University of Zielona Góra, Licealna 9, 65-417 Zielona Góra (Poland); Stachowiak, Tomasz, E-mail: stachowiak@cft.edu.pl [Center for Theoretical Physics PAS, Al. Lotnikow 32/46, 02-668 Warsaw (Poland)

    2014-10-24

    We formulate a universal method for solving an arbitrary quantum system which, in the Bargmann representation, is described by a system of linear equations with one independent variable, such as one- and multi-photon Rabi models, or N level systems interacting with a single mode of the electromagnetic field and their various generalizations. We explain three types of conditions that determine the spectrum and show their usage for two deformations of the Rabi model. We prove that the spectra of both models are just zeros of transcendental functions, which in one case are given explicitly in terms of confluent Heun functions. - Highlights: • Analytical method of spectrum determination in Bargmann representation is proposed. • Three types of conditions determining spectrum are identified. • Method to two generalizations of the Rabi system is applied.

  17. VALIDATED SPECTROPHOTMETRIC METHOD FOR THE DETERMINATION OF SALBUTAMOL SULPHATE IN BULK AND PHARMACEUTICAL DOSAGE FORMS

    OpenAIRE

    Eswarudu.M.M; Sushma.M; Sushmitha.M; Yamini.K

    2012-01-01

    A new, simple, accurate and sensitive spectrophotometric method has been developed for the estimation of Salbutamol sulphate in bulk and in pharmaceutical formulations. Salbutamol sulphate shows ʎ max at 292 nm. The drug follows the beer’s lambert’s law in the concentration range of 20-100µ ml. the method was validated by following the analytical performance parameters as suggested by the international conference on harmonization which included accuracy, precision, linearity. All validation p...

  18. The evolution of analytical chemistry methods in foodomics.

    Science.gov (United States)

    Gallo, Monica; Ferranti, Pasquale

    2016-01-08

    The methodologies of food analysis have greatly evolved over the past 100 years, from basic assays based on solution chemistry to those relying on the modern instrumental platforms. Today, the development and optimization of integrated analytical approaches based on different techniques to study at molecular level the chemical composition of a food may allow to define a 'food fingerprint', valuable to assess nutritional value, safety and quality, authenticity and security of foods. This comprehensive strategy, defined foodomics, includes emerging work areas such as food chemistry, phytochemistry, advanced analytical techniques, biosensors and bioinformatics. Integrated approaches can help to elucidate some critical issues in food analysis, but also to face the new challenges of a globalized world: security, sustainability and food productions in response to environmental world-wide changes. They include the development of powerful analytical methods to ensure the origin and quality of food, as well as the discovery of biomarkers to identify potential food safety problems. In the area of nutrition, the future challenge is to identify, through specific biomarkers, individual peculiarities that allow early diagnosis and then a personalized prognosis and diet for patients with food-related disorders. Far from the aim of an exhaustive review of the abundant literature dedicated to the applications of omic sciences in food analysis, we will explore how classical approaches, such as those used in chemistry and biochemistry, have evolved to intersect with the new omics technologies to produce a progress in our understanding of the complexity of foods. Perhaps most importantly, a key objective of the review will be to explore the development of simple and robust methods for a fully applied use of omics data in food science. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Development and validation of the analytical method by high performance liquid chromatography (HPLC for Lamotrigine raw material = Desenvolvimento e validação do método analítico por cromatografia líquida de alta eficiência (CLAE para a matéria prima Lamotrigina

    Directory of Open Access Journals (Sweden)

    Guilherme Nobre Lima do Nascimento

    2011-07-01

    Full Text Available Currently when all roads lead to the pursuit of total quality in production of drugs, it is essential to fully understand each phase of a production process. In this case, validation is the appropriate tool to ensure reliability of a production process involving new equipment and the analytical methodology, either in the pharmaceutical, food, computer, microelectronics area or any other area where the quality of the manufactured product is one of the main reasons for the existence of a given company. This study aimed to analyze the main aspects of the validation of analytical methods for Lamotrigine, new drug for bipolar disorder with wide use today. In conclusion, the proposed analytical method for determination of the lamotrigine content in raw materials is adequate, effective and capable of reproducing reliable results during analysis. This method is fast (running time of 10 minutes, selective, accurate, precise and robust for the determination of the drug, with no observedinterfering substances in the optimum wavelength. It could be concluded that this may be a routine method for quality control laboratories to certify the quality of Lamotrigine. Atualmente quando todos os caminhos levam à busca da qualidade total na produção de medicamentos, torna-se indispensável conhecer perfeitamente cada fase de um processo produtivo. Neste caso, a validação é a ferramenta adequada para garantir a confiabilidade de instalação de um processo produtivo, de equipamento novo e, inclusive, da metodologia analítica, seja do setor farmacêutico, alimentício, informática microeletrônico ou qualquer outra área onde a qualidade do produto fabricado é uma das principais razões da existência da empresa. O presente trabalho teve por objetivo analisar os principais aspectos da validação de métodos analíticos para Lamotrigina, fármaco novo para transtorno bipolar com amplo usoatualmente. Em conclusão, o método analítico proposto para determina

  20. Diffusion weighted MRI by spatiotemporal encoding: Analytical description and in vivo validations

    Science.gov (United States)

    Solomon, Eddy; Shemesh, Noam; Frydman, Lucio

    2013-07-01

    Diffusion-weighted (DW) MRI is a powerful modality for studying microstructure in normal and pathological tissues. The accuracy derived from DW MRI depends on the acquisition of quality images, and on a precise assessment of the b-values involved. Conventional DW MRI tends to be of limited use in regions suffering from large magnetic field or chemical shift heterogeneities, which severely distort the MR images. In this study we propose novel sequences based on SPatio-temporal ENcoding (SPEN), which overcome such shortcomings owing to SPEN's inherent robustness to offsets. SPEN, however, relies on the simultaneous application of gradients and radiofrequency-swept pulses, which may impart different diffusion weightings along the spatial axes. These will be further complicated in DW measurements by the diffusion-sensitizing gradients, and will in general lead to complex, spatially-dependent b-values. This study presents a formalism for analyzing these diffusion-weighted SPEN (dSPEN) data, which takes into account the concomitant effects of adiabatic pulses, of the imaging as well as diffusion gradients, and of the cross-terms between them. These analytical b-values derivations are subject to experimental validations in phantom systems and ex vivo spinal cords. Excellent agreement is found between the theoretical predictions and these dSPEN experiments. The ensuing methodology is then demonstrated by in vivo mapping of diffusion in human breast - organs where conventional k-space DW acquisition methods are challenged by both field and chemical shift heterogeneities. These studies demonstrate the increased robustness of dSPEN vis-à-vis comparable DW echo planar imaging, and demonstrate the value of this new methodology for medium- or high-field diffusion measurements in heterogeneous systems.

  1. Analytical methods manual for the Mineral Resource Surveys Program, U.S. Geological Survey

    Science.gov (United States)

    Arbogast, Belinda F.

    1996-01-01

    The analytical methods validated by the Mineral Resource Surveys Program, Geologic Division, is the subject of this manual. This edition replaces the methods portion of Open-File Report 90-668 published in 1990. Newer methods may be used which have been approved by the quality assurance (QA) project and are on file with the QA coordinator.This manual is intended primarily for use by laboratory scientists; this manual can also assist laboratory users to evaluate the data they receive. The analytical methods are written in a step by step approach so that they may be used as a training tool and provide detailed documentation of the procedures for quality assurance. A "Catalog of Services" is available for customer (submitter) use with brief listings of:the element(s)/species determined,method of determination,reference to cite,contact person,summary of the technique,and analyte concentration range.For a copy please contact the Branch office at (303) 236-1800 or fax (303) 236-3200.

  2. Analytic moment method calculations of the drift wave spectrum

    International Nuclear Information System (INIS)

    Thayer, D.R.; Molvig, K.

    1985-11-01

    A derivation and approximate solution of renormalized mode coupling equations describing the turbulent drift wave spectrum is presented. Arguments are given which indicate that a weak turbulence formulation of the spectrum equations fails for a system with negative dissipation. The inadequacy of the weak turbulence theory is circumvented by utilizing a renormalized formation. An analytic moment method is developed to approximate the solution of the nonlinear spectrum integral equations. The solution method employs trial functions to reduce the integral equations to algebraic equations in basic parameters describing the spectrum. An approximate solution of the spectrum equations is first obtained for a mode dissipation with known solution, and second for an electron dissipation in the NSA

  3. Introduction to Analytical Methods for Internal Combustion Engine Cam Mechanisms

    CERN Document Server

    Williams, J J

    2013-01-01

    Modern design methods of Automotive Cam Design require the computation of a range of parameters. This book provides a logical sequence of steps for the derivation of the relevant equations from first principles, for the more widely used cam mechanisms. Although originally derived for use in high performance engines, this work is equally applicable to the design of mass produced automotive and other internal combustion engines.   Introduction to Analytical Methods for Internal Combustion Engine Cam Mechanisms provides the equations necessary for the design of cam lift curves with an associated smooth acceleration curve. The equations are derived for the kinematics and kinetics of all the mechanisms considered, together with those for cam curvature and oil entrainment velocity. This permits the cam shape, all loads, and contact stresses to be evaluated, and the relevant tribology to be assessed. The effects of asymmetry on the manufacture of cams for finger follower and offset translating curved followers is ...

  4. Potentialities and possible applications of a new analytical method (PIXE)

    International Nuclear Information System (INIS)

    Pinho, A.G. de; Montenegro, E.C.; Barros Leite, C.V. de; Baptista, G.B.; Paschoa, A.S.

    1979-01-01

    In 1970, a new method was introduced for trace analysis, namely, the X-ray emission induced by charged particles (PIXE). It has been shown that when protons in the few MeV range are used for the excitation of inner shell electrons and solid state detectors for the detection of the characteristic X-rays, we dispose of a powerful multi-elemental analytical tool of high sensitivity. In contrast to activation spectrometry, this is an in beam technique, irradiation and measuring being performed at the same time. The foundations of the method are described experimental arrangements and problems related to beam transport, target preparation an spectrum analysis. A detailed discussion on precision, accuracy and sensitivity is presented. Applications in biology, medicine, environmental and materials sciences are discussed. (Author) [pt

  5. Structurally-compliant rocket engine combustion chamber: Experimental/analytical validation

    Science.gov (United States)

    Jankovsky, R. S.; Kazaroff, J. M.; Galford, G. R.; Arya, V. K.

    1993-11-01

    A new, structurally-compliant rocket engine combustion chamber design has been validated through analysis and experiment. Subscale, tubular channel chambers have been cyclically tested, and analytically evaluated. Cyclic lives were determined to have a potential for 1000 percent increase in life over that of rectangular channel designs, the current state-of-the-art. Greater structural compliance in the circumferential direction gives rise to lower thermal strains during hot firing, resulting in lower thermal strain ratcheting and longer predicted fatigue lives. Thermal/durability analyses of the combustion chamber design, involving cyclic temperatures, strains, and low-cycle fatigue lives have corroborated the experimental observations.

  6. GenoSets: visual analytic methods for comparative genomics.

    Directory of Open Access Journals (Sweden)

    Aurora A Cain

    Full Text Available Many important questions in biology are, fundamentally, comparative, and this extends to our analysis of a growing number of sequenced genomes. Existing genomic analysis tools are often organized around literal views of genomes as linear strings. Even when information is highly condensed, these views grow cumbersome as larger numbers of genomes are added. Data aggregation and summarization methods from the field of visual analytics can provide abstracted comparative views, suitable for sifting large multi-genome datasets to identify critical similarities and differences. We introduce a software system for visual analysis of comparative genomics data. The system automates the process of data integration, and provides the analysis platform to identify and explore features of interest within these large datasets. GenoSets borrows techniques from business intelligence and visual analytics to provide a rich interface of interactive visualizations supported by a multi-dimensional data warehouse. In GenoSets, visual analytic approaches are used to enable querying based on orthology, functional assignment, and taxonomic or user-defined groupings of genomes. GenoSets links this information together with coordinated, interactive visualizations for both detailed and high-level categorical analysis of summarized data. GenoSets has been designed to simplify the exploration of multiple genome datasets and to facilitate reasoning about genomic comparisons. Case examples are included showing the use of this system in the analysis of 12 Brucella genomes. GenoSets software and the case study dataset are freely available at http://genosets.uncc.edu. We demonstrate that the integration of genomic data using a coordinated multiple view approach can simplify the exploration of large comparative genomic data sets, and facilitate reasoning about comparisons and features of interest.

  7. No Impact of the Analytical Method Used for Determining Cystatin C on Estimating Glomerular Filtration Rate in Children.

    Science.gov (United States)

    Alberer, Martin; Hoefele, Julia; Benz, Marcus R; Bökenkamp, Arend; Weber, Lutz T

    2017-01-01

    Measurement of inulin clearance is considered to be the gold standard for determining kidney function in children, but this method is time consuming and expensive. The glomerular filtration rate (GFR) is on the other hand easier to calculate by using various creatinine- and/or cystatin C (Cys C)-based formulas. However, for the determination of serum creatinine (Scr) and Cys C, different and non-interchangeable analytical methods exist. Given the fact that different analytical methods for the determination of creatinine and Cys C were used in order to validate existing GFR formulas, clinicians should be aware of the type used in their local laboratory. In this study, we compared GFR results calculated on the basis of different GFR formulas and either used Scr and Cys C values as determined by the analytical method originally employed for validation or values obtained by an alternative analytical method to evaluate any possible effects on the performance. Cys C values determined by means of an immunoturbidimetric assay were used for calculating the GFR using equations in which this analytical method had originally been used for validation. Additionally, these same values were then used in other GFR formulas that had originally been validated using a nephelometric immunoassay for determining Cys C. The effect of using either the compatible or the possibly incompatible analytical method for determining Cys C in the calculation of GFR was assessed in comparison with the GFR measured by creatinine clearance (CrCl). Unexpectedly, using GFR equations that employed Cys C values derived from a possibly incompatible analytical method did not result in a significant difference concerning the classification of patients as having normal or reduced GFR compared to the classification obtained on the basis of CrCl. Sensitivity and specificity were adequate. On the other hand, formulas using Cys C values derived from a compatible analytical method partly showed insufficient

  8. USING ANALYTIC HIERARCHY PROCESS (AHP METHOD IN RURAL DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Tülay Cengiz

    2003-04-01

    Full Text Available Rural development is a body of economical and social policies towards improving living conditions in rural areas through enabling rural population to utilize economical, social, cultural and technological blessing of city life in place, without migrating. As it is understood from this description, rural development is a very broad concept. Therefore, in development efforts problem should be stated clearly, analyzed and many criterias should be evaluated by experts. Analytic Hierarchy Process (AHP method can be utilized at there stages of development efforts. AHP methods is one of multi-criteria decision method. After degrading a problem in smaller pieces, relative importance and level of importance of two compared elements are determined. It allows evaluation of quality and quantity factors. At the same time, it permits utilization of ideas of many experts and use them in decision process. Because mentioned features of AHP method, it could be used in rural development works. In this article, cultural factors, one of the important components of rural development is often ignored in many studies, were evaluated as an example. As a result of these applications and evaluations, it is concluded that AHP method could be helpful in rural development efforts.

  9. Analytical design method of a device for ultrasonic elliptical vibration cutting.

    Science.gov (United States)

    Huang, Weihai; Yu, Deping; Zhang, Min; Ye, Fengfei; Yao, Jin

    2017-02-01

    Ultrasonic elliptical vibration cutting (UEVC) is effective in ultraprecision diamond cutting of hard-brittle materials and ferrous metals. However, its design is quite empirical and tedious. This paper proposes an analytical design method for developing the UEVC device which works at the Flexural-Flexural complex-mode to generate the elliptical vibration. For such UEVC device, the resonant frequencies of the two flexural vibrations are required to be the same. In addition, the nodal points of the two flexural vibrations should be coincident so that the device can be clamped without affecting the vibrations. Based on the proposed analytical design method, an UEVC device was first designed. Modal analysis of the designed UEVC device was performed by using the finite element method, which shows that the resonant frequencies coincide well with the targeted ones. Then a prototype UEVC device was fabricated, and its vibration characteristics were measured by an impedance analyzer and a laser displacement sensor. Experimental results indicate that the designed UEVC device can generate elliptical vibration with the resonant frequencies closed to the target ones. In addition, the vibration trajectory can be precisely tuned by adjusting the phase difference and the amplitude of the applied voltage. Simulation and experimental results validated the effectiveness of the analytical design method.

  10. A Semi-Analytical Method for the PDFs of A Ship Rolling in Random Oblique Waves

    Science.gov (United States)

    Liu, Li-qin; Liu, Ya-liu; Xu, Wan-hai; Li, Yan; Tang, You-gang

    2018-03-01

    The PDFs (probability density functions) and probability of a ship rolling under the random parametric and forced excitations were studied by a semi-analytical method. The rolling motion equation of the ship in random oblique waves was established. The righting arm obtained by the numerical simulation was approximately fitted by an analytical function. The irregular waves were decomposed into two Gauss stationary random processes, and the CARMA (2, 1) model was used to fit the spectral density function of parametric and forced excitations. The stochastic energy envelope averaging method was used to solve the PDFs and the probability. The validity of the semi-analytical method was verified by the Monte Carlo method. The C11 ship was taken as an example, and the influences of the system parameters on the PDFs and probability were analyzed. The results show that the probability of ship rolling is affected by the characteristic wave height, wave length, and the heading angle. In order to provide proper advice for the ship's manoeuvring, the parametric excitations should be considered appropriately when the ship navigates in the oblique seas.

  11. An Analytical Method of Auxiliary Sources Solution for Plane Wave Scattering by Impedance Cylinders

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal; Breinbjerg, Olav

    2004-01-01

    Analytical Method of Auxiliary Sources solutions for plane wave scattering by circular impedance cylinders are derived by transformation of the exact eigenfunction series solutions employing the Hankel function wave transformation. The analytical Method of Auxiliary Sources solution thus obtained...

  12. An analytical solution for the nonlinear energy spectrum equation by the decomposition method

    Energy Technology Data Exchange (ETDEWEB)

    Goulart, A [Universidade Federal do Pampa, Av. Tiaraju810, 97546-550 Alegrete, RS (Brazil); Vilhena, M T M B de; Bodmann, B E J [Universidade Federal do Rio Grande do Sul, Av. Osvaldo Aranha 99/4, 90460-900 Porto Alegre, RS (Brazil); Moreira, D [Universidade Federal do Pampa, Rua Carlos Barbosa S/N, 96412-420 Bage, RS (Brazil)], E-mail: bardo.bodmann@ufrgs.br

    2008-10-24

    We discuss the isotropic turbulence decay and solve the energy density spectrum (EDS) equation considering the inertial transfer energy and viscosity terms, using the Heisenberg parameterization. In the present approach, buoyant and shear terms are neglected and turbulence is assumed to be homogeneous and isotropic. The nonlinear integro-differential equation is solved by Adomian's generic decomposition method, which yields an analytical recursive expression and upon truncation gives an approximate solution. We show the resulting EDS and the time-dependent decay of the intensity of the turbulent kinetic energy. Our results prove consistent the Heisenberg parameterization for the transfer term of the inertial energy. The analytical character of the solution permits a validation of the nonlinear details of the physical model.

  13. An analytically based numerical method for computing view factors in real urban environments

    Science.gov (United States)

    Lee, Doo-Il; Woo, Ju-Wan; Lee, Sang-Hyun

    2018-01-01

    A view factor is an important morphological parameter used in parameterizing in-canyon radiative energy exchange process as well as in characterizing local climate over urban environments. For realistic representation of the in-canyon radiative processes, a complete set of view factors at the horizontal and vertical surfaces of urban facets is required. Various analytical and numerical methods have been suggested to determine the view factors for urban environments, but most of the methods provide only sky-view factor at the ground level of a specific location or assume simplified morphology of complex urban environments. In this study, a numerical method that can determine the sky-view factors ( ψ ga and ψ wa ) and wall-view factors ( ψ gw and ψ ww ) at the horizontal and vertical surfaces is presented for application to real urban morphology, which are derived from an analytical formulation of the view factor between two blackbody surfaces of arbitrary geometry. The established numerical method is validated against the analytical sky-view factor estimation for ideal street canyon geometries, showing a consolidate confidence in accuracy with errors of less than 0.2 %. Using a three-dimensional building database, the numerical method is also demonstrated to be applicable in determining the sky-view factors at the horizontal (roofs and roads) and vertical (walls) surfaces in real urban environments. The results suggest that the analytically based numerical method can be used for the radiative process parameterization of urban numerical models as well as for the characterization of local urban climate.

  14. Computational and analytical methods in nonlinear fluid dynamics

    Science.gov (United States)

    Walker, James

    1993-09-01

    The central focus of the program was on the application and development of modern analytical and computational methods to the solution of nonlinear problems in fluid dynamics and reactive gas dynamics. The research was carried out within the Division of Engineering Mathematics in the Department of Mechanical Engineering and Mechanics and principally involved Professors P.A. Blythe, E. Varley and J.D.A. Walker. In addition. the program involved various international collaborations. Professor Blythe completed work on reactive gas dynamics with Professor D. Crighton FRS of Cambridge University in the United Kingdom. Professor Walker and his students carried out joint work with Professor F.T. Smith, of University College London, on various problems in unsteady flow and turbulent boundary layers.

  15. Laser induced uranium fluorescence as an analytical method

    International Nuclear Information System (INIS)

    Krutman, I.

    1985-01-01

    A laser induced fluorescence system was developed to measure uranium trace level amounts in aqueous solution with reliable and simple materials and electronics. A nitrogen pulsed laser was built with the storage energy capacitor directly coupled to laser tube electrodes as a transmission line device. This laser operated at 3Hz repetition rate with peak intensity around 21 Kw and temporal width of 4.5 x 10 -9 s. A sample compartment made of rigid PVC and a photomultiplier housing of aluminium were constructed and assembled forming a single integrated device. As a result of this prototype system we made several analytical measurements with U dissolved in nitric acid to obtain a calibration curve. We obtained a straight line from a plot of U concentration versus fluorescence intensity fitted by a least square method that produced a regression coefficient of 0.994. The lower limit of U determination was 30 ppb -+ 3.5%. (Author) [pt

  16. Analytical methods and problems for the diamides type of extractants

    International Nuclear Information System (INIS)

    Cuillerdier, C.; Nigond, L.; Musikas, C.; Vitart, H.; Hoel, P.

    1989-01-01

    Diamides of carboxylic acids and especially malonamides are able to extract alpha emitters (including trivalent ions such as Am and Cm) contained in the wastes solutions of the nuclear industry. As they are completely incinerable and easy to purify, they could be an alternative to the mixture CMPO-TBP which is used in the TRUEX process. A large oxyalkyl radical enhances the distribution coefficients of americium in nitric acid sufficiently to permit the decontamination of wastes solutions in a classical mixers-settlers battery. Now researches are pursued with the aim of optimizing the formula of extractant, the influence of the structure of the extractant on its basicity and stability under radiolysis and hydrolysis is investigated. Analytical methods (potentiometry and NMR of C 13 ) have been developed for solvent titration and to evaluate the percentage of degradation and to identify some of the degradation products

  17. Nuclear analytical methods for trace element studies in calcified tissues

    International Nuclear Information System (INIS)

    Chaudhry, M.A.; Chaudhry, M.N.

    2001-01-01

    Full text: Various nuclear analytical methods have been developed and applied to determine the elemental composition of calcified tissues (teeth and bones). Fluorine was determined by prompt gamma activation analysis through the 19 F(p,ag) 16 O reaction. Carbon was measured by activation analysis with He-3 ions, and the technique of Proton-Induced X-ray Emission (PIXE) was applied to simultaneously determine Ca, P, and trace elements in well-documented teeth. Dental hard tissues, enamel, dentine, cement, and their junctions, as well as different parts of the same tissue, were examined separately. Furthermore, using a Proton Microprobe, we measured the surface distribution of F and other elements on and around carious lesions on the enamel. The depth profiles of F, and other elements, were also measured right up to the amelodentin junction

  18. Application of analytical methods in authentication and adulteration of honey.

    Science.gov (United States)

    Siddiqui, Amna Jabbar; Musharraf, Syed Ghulam; Choudhary, M Iqbal; Rahman, Atta-Ur-

    2017-02-15

    Honey is synthesized from flower nectar and it is famous for its tremendous therapeutic potential since ancient times. Many factors influence the basic properties of honey including the nectar-providing plant species, bee species, geographic area, and harvesting conditions. Quality and composition of honey is also affected by many other factors, such as overfeeding of bees with sucrose, harvesting prior to maturity, and adulteration with sugar syrups. Due to the complex nature of honey, it is often challenging to authenticate the purity and quality by using common methods such as physicochemical parameters and more specialized procedures need to be developed. This article reviews the literature (between 2000 and 2016) on the use of analytical techniques, mainly NMR spectroscopy, for authentication of honey, its botanical and geographical origin, and adulteration by sugar syrups. NMR is a powerful technique and can be used as a fingerprinting technique to compare various samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Analytical methods used in plutonium purification cycles by trilaurylamine

    International Nuclear Information System (INIS)

    Perez, J.J.

    1965-01-01

    The utilisation of trilaurylamine as a solvent extractant for the purification of plutonium has entailed to perfect a set of analytical methods which involves, various techniques. The organic impurities of the solvent can be titrated by gas-liquid chromatography. The titration of the main degradation product, the di-laurylamine, can be accomplished also by spectro-colorimetry. Potentiometry is used for the analysis of the different salts of amine-nitrate-sulfate-bisulfate as also the extracted nitric acid. The determination of the nitrate in aqueous phase is carried out by constant current potentiometry. The range of application, the accuracy and the procedure of these analysis are related in the present report. (author) [fr

  20. Precision profiles and analytic reliability of radioimmunologic methods

    International Nuclear Information System (INIS)

    Yaneva, Z.; Popova, Yu.

    1991-01-01

    The aim of the present study is to investigate and compare some methods for creation of 'precision profiles' (PP) and to clarify their possibilities for determining the analytical reliability of RIA. Only methods without complicated mathematical calculations has been used. The reproducibility in serums with a concentration of the determinable hormone in the whole range of the calibration curve has been studied. The radioimmunoassay has been performed with TSH-RIA set (ex East Germany), and comparative evaluations - with commercial sets of HOECHST (Germany) and AMERSHAM (GB). Three methods for obtaining the relationship concentration (IU/l) -reproducibility (C.V.,%) are used and a comparison is made of their corresponding profiles: preliminary rough profile, Rodbard-PP and Ekins-PP. It is concluded that the creation of a precision profile is obligatory and the method of its construction does not influence the relationship's course. PP allows to determine concentration range giving stable results which improves the efficiency of the analitical work. 16 refs., 4 figs

  1. Validation of spectrophotometric method for lactulose assay in syrup preparation

    Science.gov (United States)

    Mahardhika, Andhika Bintang; Novelynda, Yoshella; Damayanti, Sophi

    2015-09-01

    Lactulose is a synthetic disaccharide widely used in food and pharmaceutical fields. In the pharmaceutical field, lactulose is used as osmotic laxative in a syrup dosage form. This research was aimed to validate the spectrophotometric method to determine the levels of lactulose in syrup preparation and the commercial sample. Lactulose is hydrolyzed by hydrochloric acid to form fructose and galactose. The fructose was reacted with resorcinol reagent, forming compounds that give absorption peak at 485 nm. Analytical methods was validated, hereafter lactulose content in syrup preparation were determined. The calibration curve was linear in the range of 30-100 μg/mL with a correlation coefficient (r) of 0.9996, coefficient of variance (Vxo) of 1.1 %, limit of detection of 2.32 μg/mL, and limit of quantitation of 7.04 μg/mL. The result of accuracy test for the lactulose assay in the syrup preparation showed recoveries of 96.6 to 100.8 %. Repeatability test of lactulose assay in standard solution of lactulose and sample preparation syrup showed the coefficient of variation (CV) of 0.75 % and 0.7 %. Intermediate precision (interday) test resulted in coefficient of variation 1.06 % on the first day, the second day by 0.99 %, and 0.95 % for the third day. This research gave a valid analysis method and levels of lactulose in syrup preparations of samples A, B, C were 101.6, 100.5, and 100.6 %, respectively.

  2. Analytical and clinical validation of parathyroid hormone (PTH) measurement in fine-needle aspiration biopsy (FNAB) washings.

    Science.gov (United States)

    Ketha, Hemamalini; Lasho, Michael A; Algeciras-Schimnich, Alicia

    2016-01-01

    Parathyroid hormone (PTH) quantitation in fine needle aspirate biopsy (FNAB) saline washings complements current modalities for parathyroid tissue localization. To establish the performance characteristics of the Roche Elecsys intact PTH immunoassay in FNAB needle washings and its diagnostic performance for the identification of parathyroid tissue. Accuracy, precision, reportable range, and analytical specificity and sensitivity for the intact PTH immunoassay in FNAB needle washings were established. For clinical validation, 93 specimens from 79 patients were evaluated. Diagnostic cut-offs were established via receiver operator characteristic (ROC) curve analysis. Performance of PTH in FNAB needle washings was compared to cytology. Measurement of the PTH in FNAB needle washings demonstrated a matrix interference that was overcome by supplementation of the samples with a protein based matrix prior to analysis. ROC area under the curve (AUC) was 0.96 for PTH in FNAB needle washings. A PTH concentration ≥100pg/mL showed 100% specificity and 82% sensitivity for identifying parathyroid tissue. On histology-confirmed parathyroid specimens, 21/38 (55%) were correctly identified by cytology; whereas 31/38 (82%) were identified by PTH. Measurement of PTH in FNAB washings complements cytology for identification of parathyroid tissue. Analytical validation to exclude interference in the PTH immunoassay and proper localization of the parathyroid tissue by ultrasound is necessary to ensure the robustness of the method. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  3. A novel analytical approximation technique for highly nonlinear oscillators based on the energy balance method

    Directory of Open Access Journals (Sweden)

    Md. Alal Hosen

    2016-01-01

    Full Text Available In the present paper, a novel analytical approximation technique has been proposed based on the energy balance method (EBM to obtain approximate periodic solutions for the focus generalized highly nonlinear oscillators. The expressions of the natural frequency-amplitude relationship are obtained using a novel analytical way. The accuracy of the proposed method is investigated on three benchmark oscillatory problems, namely, the simple relativistic oscillator, the stretched elastic wire oscillator (with a mass attached to its midpoint and the Duffing-relativistic oscillator. For an initial oscillation amplitude A0 = 100, the maximal relative errors of natural frequency found in three oscillators are 2.1637%, 0.0001% and 1.201%, respectively, which are much lower than the errors found using the existing methods. It is highly remarkable that an excellent accuracy of the approximate natural frequency has been found which is valid for the whole range of large values of oscillation amplitude as compared with the exact ones. Very simple solution procedure and high accuracy that is found in three benchmark problems reveal the novelty, reliability and wider applicability of the proposed analytical approximation technique.

  4. The Method of Manufactured Universes for validating uncertainty quantification methods

    KAUST Repository

    Stripling, H.F.

    2011-09-01

    The Method of Manufactured Universes is presented as a validation framework for uncertainty quantification (UQ) methodologies and as a tool for exploring the effects of statistical and modeling assumptions embedded in these methods. The framework calls for a manufactured reality from which experimental data are created (possibly with experimental error), an imperfect model (with uncertain inputs) from which simulation results are created (possibly with numerical error), the application of a system for quantifying uncertainties in model predictions, and an assessment of how accurately those uncertainties are quantified. The application presented in this paper manufactures a particle-transport universe, models it using diffusion theory with uncertain material parameters, and applies both Gaussian process and Bayesian MARS algorithms to make quantitative predictions about new experiments within the manufactured reality. The results of this preliminary study indicate that, even in a simple problem, the improper application of a specific UQ method or unrealized effects of a modeling assumption may produce inaccurate predictions. We conclude that the validation framework presented in this paper is a powerful and flexible tool for the investigation and understanding of UQ methodologies. © 2011 Elsevier Ltd. All rights reserved.

  5. Groundwater Seepage Estimation into Amirkabir Tunnel Using Analytical Methods and DEM and SGR Method

    OpenAIRE

    Hadi Farhadian; Homayoon Katibeh

    2015-01-01

    In this paper, groundwater seepage into Amirkabir tunnel has been estimated using analytical and numerical methods for 14 different sections of the tunnel. Site Groundwater Rating (SGR) method also has been performed for qualitative and quantitative classification of the tunnel sections. The obtained results of above mentioned methods were compared together. The study shows reasonable accordance with results of the all methods unless for two sections of tunnel. In these t...

  6. Analytical methods associated with the recovery of uranium

    International Nuclear Information System (INIS)

    Dixon, K.

    1983-01-01

    This report summarizes various approaches made to the analysis of materials arising from the processing of Karoo deposits for uranium. These materials include head and residue samples, aqueous solutions and organic solvents and, finally, the precipitated cakes of the elements recovered, i.e. uranium, molybdenum, and arsenic. Analysis was required for these elements and also vanadium, carbon, sulphur, and carbonate in the head and residue samples. The concentration of uranium, molybdenum, and arsenic, other than in the precipitated cakes, ranges from 1 to 2000μg/g, and that of carbon, sulphur, and carbonate from 0,1 to 5 per cent. The analysis of cakes necessitates the determination of silver, arsenic, iron, copper, calcium, magnesium, manganese, molybdenum, lead, tin, titanium, and vanadium within the range 1 to 1000μg/g, and of sodium and silica within the range 10 to 20 000μg/g. The methods used include combustion methods for carbon, sulphur, and carbonate, and atomic-absorption, X-ray-fluorescence, and emission methods for the other analytes. The accuracy of the analysis is within 10 per cent

  7. Short-Term Predictive Validity of Cluster Analytic and Dimensional Classification of Child Behavioral Adjustment in School

    Science.gov (United States)

    Kim, Sangwon; Kamphaus, Randy W.; Baker, Jean A.

    2006-01-01

    A constructive debate over the classification of child psychopathology can be stimulated by investigating the validity of different classification approaches. We examined and compared the short-term predictive validity of cluster analytic and dimensional classifications of child behavioral adjustment in school using the Behavior Assessment System…

  8. Analytical resource assessment method for continuous (unconventional) oil and gas accumulations - The "ACCESS" Method

    Science.gov (United States)

    Crovelli, Robert A.; revised by Charpentier, Ronald R.

    2012-01-01

    The U.S. Geological Survey (USGS) periodically assesses petroleum resources of areas within the United States and the world. The purpose of this report is to explain the development of an analytic probabilistic method and spreadsheet software system called Analytic Cell-Based Continuous Energy Spreadsheet System (ACCESS). The ACCESS method is based upon mathematical equations derived from probability theory. The ACCESS spreadsheet can be used to calculate estimates of the undeveloped oil, gas, and NGL (natural gas liquids) resources in a continuous-type assessment unit. An assessment unit is a mappable volume of rock in a total petroleum system. In this report, the geologic assessment model is defined first, the analytic probabilistic method is described second, and the spreadsheet ACCESS is described third. In this revised version of Open-File Report 00-044 , the text has been updated to reflect modifications that were made to the ACCESS program. Two versions of the program are added as appendixes.

  9. Validation of methods for the detection and quantification of engineered nanoparticles in food

    DEFF Research Database (Denmark)

    Linsinger, T.P.J.; Chaudhry, Q.; Dehalu, V.

    2013-01-01

    The potential impact of nanomaterials on the environment and on human health has already triggered legislation requiring labelling of products containing nanoparticles. However, so far, no validated analytical methods for the implementation of this legislation exist. This paper outlines a generic...

  10. Validation of methods for the detection and quantification of engineered nanoparticles in food

    NARCIS (Netherlands)

    Linsinger, T.P.J.; Chaudhry, Q.; Dehalu, V.; Delahaut, P.; Dudkiewicz, A.; Grombe, R.; Kammer, von der F.; Larsen, E.H.; Legros, S.; Loeschner, K.; Peters, R.; Ramsch, R.; Roebben, G.; Tiede, K.; Weigel, S.

    2013-01-01

    The potential impact of nanomaterials on the environment and on human health has already triggered legislation requiring labelling of products containing nanoparticles. However, so far, no validated analytical methods for the implementation of this legislation exist. This paper outlines a generic

  11. Validation of the ultraviolet spectrophotometry method for the quality control of ciprofloxacin chlorhydrate in Ciprecu tablets

    International Nuclear Information System (INIS)

    Perez Navarro, Maikel; Rodriguez Hernandez, Yaslenis; Suarez Perez, Yania

    2014-01-01

    Quinolones are a group of antimicrobials of high clinical significance. Ciprofloxacin hydrochloride monohydrate is a second-generation antibacterial fluoroquinolone for treatment of several infections and is marketed as eye drops, injections, capsule and tablets. To develop and to validate an ultraviolet spectrophotometric analytical method to be used in the quality control of ciprofloxacin hydrochloride monohydrate in newly manufactured Ciprecu tablets

  12. Characterization of Compton-scatter imaging with an analytical simulation method

    Science.gov (United States)

    Jones, Kevin C.; Redler, Gage; Templeton, Alistair; Bernard, Damian; Turian, Julius V.; Chu, James C. H.

    2018-01-01

    By collimating the photons scattered when a megavoltage therapy beam interacts with the patient, a Compton-scatter image may be formed without the delivery of an extra dose. To characterize and assess the potential of the technique, an analytical model for simulating scatter images was developed and validated against Monte Carlo (MC). For three phantoms, the scatter images collected during irradiation with a 6 MV flattening-filter-free therapy beam were simulated. Images, profiles, and spectra were compared for different phantoms and different irradiation angles. The proposed analytical method simulates accurate scatter images up to 1000 times faster than MC. Minor differences between MC and analytical simulated images are attributed to limitations in the isotropic superposition/convolution algorithm used to analytically model multiple-order scattering. For a detector placed at 90° relative to the treatment beam, the simulated scattered photon energy spectrum peaks at 140-220 keV, and 40-50% of the photons are the result of multiple scattering. The high energy photons originate at the beam entrance. Increasing the angle between source and detector increases the average energy of the collected photons and decreases the relative contribution of multiple scattered photons. Multiple scattered photons cause blurring in the image. For an ideal 5 mm diameter pinhole collimator placed 18.5 cm from the isocenter, 10 cGy of deposited dose (2 Hz imaging rate for 1200 MU min-1 treatment delivery) is expected to generate an average 1000 photons per mm2 at the detector. For the considered lung tumor CT phantom, the contrast is high enough to clearly identify the lung tumor in the scatter image. Increasing the treatment beam size perpendicular to the detector plane decreases the contrast, although the scatter subject contrast is expected to be greater than the megavoltage transmission image contrast. With the analytical method, real-time tumor tracking may be possible

  13. A Multi-Projector Calibration Method for Virtual Reality Simulators with Analytically Defined Screens

    Directory of Open Access Journals (Sweden)

    Cristina Portalés

    2017-06-01

    Full Text Available The geometric calibration of projectors is a demanding task, particularly for the industry of virtual reality simulators. Different methods have been developed during the last decades to retrieve the intrinsic and extrinsic parameters of projectors, most of them being based on planar homographies and some requiring an extended calibration process. The aim of our research work is to design a fast and user-friendly method to provide multi-projector calibration on analytically defined screens, where a sample is shown for a virtual reality Formula 1 simulator that has a cylindrical screen. The proposed method results from the combination of surveying, photogrammetry and image processing approaches, and has been designed by considering the spatial restrictions of virtual reality simulators. The method has been validated from a mathematical point of view, and the complete system—which is currently installed in a shopping mall in Spain—has been tested by different users.

  14. Validación de métodos analíticos para los estudios de estabilidad del naproxeno en supositorios para uso infantil y adulto Validation of analytical methods for the stability studies of naproxen suppositories for infant and adult use

    Directory of Open Access Journals (Sweden)

    Yaslenis Rodríguez Hernández

    2011-12-01

    Full Text Available En el presente trabajo se realizaron los estudios analíticos y de validación para su aplicación en los estudios de estabilidad de las futuras formulaciones de supositorios de naproxeno para uso infantil y adulto. Se determinaron los factores que más influyeron en la estabilidad del naproxeno; la mayor degradación ocurrió en el medio ácido, oxidante y por acción de la luz. Se evaluó un método por cromatografía líquida de alta resolución, el cual mostró adecuado desempeño para cuantificar naproxeno en supositorios y fue selectivo frente a los productos de degradación. Se obtuvo un límite de cuantificación de 3,480 µg, por lo que fue válido para la realización de dichos estudios. Adicionalmente, se evaluaron los parámetros especificidad para estabilidad, límites de detección y de cuantificación para el método por volumetría ácido-base semiacuosa directa validado anteriormente para control de calidad, lo cual mostró resultados satisfactorios. No obstante, los métodos volumétricos no se consideran indicadores de estabilidad, por lo que este método será utilizado conjuntamente con los métodos cromatográficos de elección para determinar productos de degradación: cromatografía de capa delgada y cromatografía líquida de alta resolución.Analytical and validating studies were performed in this paper, with a view to using them in the stability studies of the future formulations of naproxen suppositories for children and adults. The most influential factors in the naproxen stability were determined, that is, the major degradation occurred in acid medium, oxidative medium and by light action. One high-performance liquid chromatography-based method was evaluated, which proved to be adequate to quantify naproxen in suppositories and was selective against degradation products. The quantification limit was 3,480 µg, so it was valid for these studies. Additionally, the parameters specificity for stability, detection and

  15. An analytical method for predicting postwildfire peak discharges

    Science.gov (United States)

    Moody, John A.

    2012-01-01

    An analytical method presented here that predicts postwildfire peak discharge was developed from analysis of paired rainfall and runoff measurements collected from selected burned basins. Data were collected from 19 mountainous basins burned by eight wildfires in different hydroclimatic regimes in the western United States (California, Colorado, Nevada, New Mexico, and South Dakota). Most of the data were collected for the year of the wildfire and for 3 to 4 years after the wildfire. These data provide some estimate of the changes with time of postwildfire peak discharges, which are known to be transient but have received little documentation. The only required inputs for the analytical method are the burned area and a quantitative measure of soil burn severity (change in the normalized burn ratio), which is derived from Landsat reflectance data and is available from either the U.S. Department of Agriculture Forest Service or the U.S. Geological Survey. The method predicts the postwildfire peak discharge per unit burned area for the year of a wildfire, the first year after a wildfire, and the second year after a wildfire. It can be used at three levels of information depending on the data available to the user; each subsequent level requires either more data or more processing of the data. Level 1 requires only the burned area. Level 2 requires the burned area and the basin average value of the change in the normalized burn ratio. Level 3 requires the burned area and the calculation of the hydraulic functional connectivity, which is a variable that incorporates the sequence of soil burn severity along hillslope flow paths within the burned basin. Measurements indicate that the unit peak discharge response increases abruptly when the 30-minute maximum rainfall intensity is greater than about 5 millimeters per hour (0.2 inches per hour). This threshold may relate to a change in runoff generation from saturated-excess to infiltration-excess overland flow. The

  16. Measurement of company effectiveness using analytic network process method

    Science.gov (United States)

    Goran, Janjić; Zorana, Tanasić; Borut, Kosec

    2017-07-01

    The sustainable development of an organisation is monitored through the organisation's performance, which beforehand incorporates all stakeholders' requirements in its strategy. The strategic management concept enables organisations to monitor and evaluate their effectiveness along with efficiency by monitoring of the implementation of set strategic goals. In the process of monitoring and measuring effectiveness, an organisation can use multiple-criteria decision-making methods as help. This study uses the method of analytic network process (ANP) to define the weight factors of the mutual influences of all the important elements of an organisation's strategy. The calculation of an organisation's effectiveness is based on the weight factors and the degree of fulfilment of the goal values of the strategic map measures. New business conditions influence the changes in the importance of certain elements of an organisation's business in relation to competitive advantage on the market, and on the market, increasing emphasis is given to non-material resources in the process of selection of the organisation's most important measures.

  17. Measurement of company effectiveness using analytic network process method

    Directory of Open Access Journals (Sweden)

    Goran Janjić

    2017-07-01

    Full Text Available The sustainable development of an organisation is monitored through the organisation’s performance, which beforehand incorporates all stakeholders’ requirements in its strategy. The strategic management concept enables organisations to monitor and evaluate their effectiveness along with efficiency by monitoring of the implementation of set strategic goals. In the process of monitoring and measuring effectiveness, an organisation can use multiple-criteria decision-making methods as help. This study uses the method of analytic network process (ANP to define the weight factors of the mutual influences of all the important elements of an organisation’s strategy. The calculation of an organisation’s effectiveness is based on the weight factors and the degree of fulfilment of the goal values of the strategic map measures. New business conditions influence the changes in the importance of certain elements of an organisation’s business in relation to competitive advantage on the market, and on the market, increasing emphasis is given to non-material resources in the process of selection of the organisation’s most important measures.

  18. Analytic-numerical method of determining the freezing front location

    Directory of Open Access Journals (Sweden)

    R. Grzymkowski

    2011-07-01

    Full Text Available Mathematical modeling of thermal processes combined with the reversible phase transitions of type: solid phase – liquid phase leads to formulation of the parabolic boundary problems with the moving boundary. Solution of such defined problem requires, most often, to use sophisticated numerical techniques and far advanced mathematical tools. Excellent illustration of the complexity of considered problems, as well as of the variety of approaches used for finding their solutions, gives the papers [1-4]. In the current paper, the authors present the, especially attractive from the engineer point of view, analytic-numerical method for finding the approximate solution of selected class of problems which can be reduced to the one-phase solidification problem of a plate with the unknown a priori, varying in time boundary of the region in which the solution is sought. Proposed method is based on the known formalism of initial expansion of the sought function describing the temperature field into the power series, some coefficients of which are determined with the aid of boundary conditions, and on the approximation of the function defining the location of freezing front with the broken line, parameters of which are numerically determined.

  19. Quality control and analytical methods for baculovirus-based products.

    Science.gov (United States)

    Roldão, António; Vicente, Tiago; Peixoto, Cristina; Carrondo, Manuel J T; Alves, Paula M

    2011-07-01

    Recombinant baculoviruses (rBac) are used for many different applications, ranging from bio-insecticides to the production of heterologous proteins, high-throughput screening of gene functions, drug delivery, in vitro assembly studies, design of antiviral drugs, bio-weapons, building blocks for electronics, biosensors and chemistry, and recently as a delivery system in gene therapy. Independent of the application, the quality, quantity and purity of rBac-based products are pre-requisites demanded by regulatory authorities for product licensing. To guarantee maximization utility, it is necessary to delineate optimized production schemes either using trial-and-error experimental setups ("brute force" approach) or rational design of experiments by aid of in silico mathematical models (Systems Biology approach). For that, one must define all of the main steps in the overall process, identify the main bioengineering issues affecting each individual step and implement, if required, accurate analytical methods for product characterization. In this review, current challenges for quality control (QC) technologies for up- and down-stream processing of rBac-based products are addressed. In addition, a collection of QC methods for monitoring/control of the production of rBac derived products are presented as well as innovative technologies for faster process optimization and more detailed product characterization. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Modern analytic methods applied to the art and archaeology

    International Nuclear Information System (INIS)

    Tenorio C, M. D.; Longoria G, L. C.

    2010-01-01

    The interaction of diverse areas as the analytic chemistry, the history of the art and the archaeology has allowed the development of a variety of techniques used in archaeology, in conservation and restoration. These methods have been used to date objects, to determine the origin of the old materials and to reconstruct their use and to identify the degradation processes that affect the integrity of the art works. The objective of this chapter is to offer a general vision on the researches that have been realized in the Instituto Nacional de Investigaciones Nucleares (ININ) in the field of cultural goods. A series of researches carried out in collaboration with national investigators and of the foreigner is described shortly, as well as with the great support of degree students and master in archaeology of the National School of Anthropology and History, since one of the goals that have is to diffuse the knowledge of the existence of these techniques among the young archaeologists, so that they have a wider vision of what they could use in an in mediate future and they can check hypothesis with scientific methods. (Author)

  1. Development of analytical methods for iodine speciation in fresh water

    International Nuclear Information System (INIS)

    Takaku, Yuichi; Ohtsuka, Yoshihito; Hisamatsu, Shun'ichi

    2007-01-01

    Analytical methods for physicochemical speciation of iodine in fresh water samples were developed to elucidate its behavior in the environment. The methods combined inductively coupled plasma mass spectrometry (ICP-MS) with size exclusion high performance liquid chromatography (SEC) or capillary electrophoresis (CE). Freshwater samples were collected from Lake Towada and rivers surrounding the lake. After filtration through a 0.45 μm pore size membrane filter, iodine in the water samples was pre-concentrated with an ultra-filtration filter which had a cut-off size of 10 kDa. The fraction with molecular size over 10 kDa was concentrated to 100 times in the original water, and then introduced into the SEC-ICP-MS. Molecular size chromatograms of all river and lake water samples showed two peaks for iodine concentrations: 40 kDa and 20 kDa. The method for separately determining two valence states of inorganic iodine, I - and IO 3 - , was also developed using the CE-ICP-MS system and it was successfully applied to the fresh water samples. Analysis results of surface water samples in Lake Towada and rivers surrounding the lake indicated that the chemical form of inorganic iodine in all samples was IO 3 - . Additional lake water samples were collected from Lake O-ike-higashi in the Juni-ko area at Shirakami-Sanchi, which is a UNESCO natural world heritage. The lake has a strong thermocline during all seasons; its bottom layer is in a highly reductive state. Depth profiles of I - and IO 3 - clearly showed that I - was not detected in the surface layer, but it was predominant in the bottom layer, and vice versa for IO 3 - . As this separation method is rapid and sensitive, it will be widely used in the future. (author)

  2. Propulsion and launching analysis of variable-mass rockets by analytical methods

    OpenAIRE

    D.D. Ganji; M. Gorji; M. Hatami; A. Hasanpour; N. Khademzadeh

    2013-01-01

    In this study, applications of some analytical methods on nonlinear equation of the launching of a rocket with variable mass are investigated. Differential transformation method (DTM), homotopy perturbation method (HPM) and least square method (LSM) were applied and their results are compared with numerical solution. An excellent agreement with analytical methods and numerical ones is observed in the results and this reveals that analytical methods are effective and convenient. Also a paramet...

  3. Analytical one parameter method for PID motion controller settings

    NARCIS (Netherlands)

    van Dijk, Johannes; Aarts, Ronald G.K.M.

    2012-01-01

    In this paper analytical expressions for PID-controllers settings for electromechanical motion systems are presented. It will be shown that by an adequate frequency domain oriented parametrization, the parameters of a PID-controller are analytically dependent on one variable only, the cross-over

  4. Migração de β-caprolactama de embalagens contendo poliamida 6 para simulante ácido acético 3% e validação do método analítico β-Caprolactam migration from polyamide 6 packaging into 3% acetic acid food simulant and validation of the analytical method

    Directory of Open Access Journals (Sweden)

    Juliana Silva Félix

    2007-08-01

    Full Text Available Este trabalho teve como objetivo desenvolver e validar método analítico para determinar ε-caprolactama no simulante de alimentos solução de ácido acético 3% e estudar sua migração de embalagens contendo poliamida 6 para o simulante em contato. Foi empregada a cromatografia gasosa usando ε-caprolactama como padrão analítico e 2-azociclononanona como padrão interno. A linearidade esteve entre 1,60 e 640,00 µg de ε-caprolactama.mL-1 de simulante, com coeficiente de correlação 0,9999. Os limites de detecção e de quantificação do método foram 0,24 e 1,60 ng, respectivamente. A precisão do método revelou valores de coeficiente de variação menores que 4,3% e a avaliação da exatidão mostrou recuperação de 100 a 106%. O método demonstrou ser eficaz para quantificar ε-caprolactama no simulante, apresentando ampla linearidade, boa precisão e exatidão. No ensaio de migração, embalagens contendo poliamida 6 foram colocadas em tubos de vidro com 10 mL do simulante, que foram hermeticamente fechados e acondicionados a 40 ± 1 °C durante 10 dias. O ensaio de migração foi realizado por imersão total. A quantidade de ε-caprolactama migrada variou de 7,8 a 10,5 e de 6,9 a 7,6 mg.kg-1 de simulante para as embalagens destinadas aos produtos cárneos e queijos, respectivamente. Todas as embalagens atenderam às exigências da Legislação Brasileira para migração de ε-caprolactama.The aim of this work was to develop and validate an analytical method to determine ε-caprolactam in 3% acetic acid solution and to study its migration from polyamide 6 into food simulant. Gas chromatography was used with ε-caprolactam as an analytical standard and 2-azacyclononanone as an internal standard. The linearity was obtained by the concentration range of 1.60 to 640.00 µg.mL-1, with a correlation coefficient of 0.9999. Detection and quantification limits of the method were 0.24 ng and 1.60 ng, respectively. Relative standard

  5. Analytical validation and reference intervals for freezing point depression osmometer measurements of urine osmolality in dogs.

    Science.gov (United States)

    Guerrero, Samantha; Pastor, Josep; Tvarijonaviciute, Asta; Cerón, José Joaquín; Balestra, Graziano; Caldin, Marco

    2017-11-01

    Urine osmolality (UOsm) is considered the most accurate measure of urine concentration and is used to assess body fluid homeostasis and renal function. We performed analytical validation of freezing point depression measurement of canine UOsm, to establish reference intervals (RIs) and to determine the effect of age, sex, and reproductive status on UOsm in dogs. Clinically healthy dogs ( n = 1,991) were retrospectively selected and stratified in groups by age (young [0-12 mo], adults [13-84 mo], and seniors [>84 mo]), sex (females and males), and reproductive status (intact and neutered). RIs were calculated for each age group. Intra- and inter-assay coefficients of variation were dogs, and 366-2,178 mOsm/kg in seniors. Senior dogs had a significantly lower UOsm than young and adult dogs ( p dogs ( p dogs.

  6. Analytical Performance Modeling and Validation of Intel’s Xeon Phi Architecture

    Energy Technology Data Exchange (ETDEWEB)

    Chunduri, Sudheer; Balaprakash, Prasanna; Morozov, Vitali; Vishwanath, Venkatram; Kumaran, Kalyan

    2017-01-01

    Modeling the performance of scientific applications on emerging hardware plays a central role in achieving extreme-scale computing goals. Analytical models that capture the interaction between applications and hardware characteristics are attractive because even a reasonably accurate model can be useful for performance tuning before the hardware is made available. In this paper, we develop a hardware model for Intel’s second-generation Xeon Phi architecture code-named Knights Landing (KNL) for the SKOPE framework. We validate the KNL hardware model by projecting the performance of mini-benchmarks and application kernels. The results show that our KNL model can project the performance with prediction errors of 10% to 20%. The hardware model also provides informative recommendations for code transformations and tuning.

  7. Simplex and duplex event-specific analytical methods for functional biotech maize.

    Science.gov (United States)

    Lee, Seong-Hun; Kim, Su-Jeong; Yi, Bu-Young

    2009-08-26

    Analytical methods are very important in the control of genetically modified organism (GMO) labeling systems or living modified organism (LMO) management for biotech crops. Event-specific primers and probes were developed for qualitative and quantitative analysis for biotech maize event 3272 and LY 038 on the basis of the 3' flanking regions, respectively. The qualitative primers confirmed the specificity by a single PCR product and sensitivity to 0.05% as a limit of detection (LOD). Simplex and duplex quantitative methods were also developed using TaqMan real-time PCR. One synthetic plasmid was constructed from two taxon-specific DNA sequences of maize and two event-specific 3' flanking DNA sequences of event 3272 and LY 038 as reference molecules. In-house validation of the quantitative methods was performed using six levels of mixing samples, from 0.1 to 10.0%. As a result, the biases from the true value and the relative deviations were all within the range of +/-30%. Limits of quantitation (LOQs) of the quantitative methods were all 0.1% for simplex real-time PCRs of event 3272 and LY 038 and 0.5% for duplex real-time PCR of LY 038. This study reports that event-specific analytical methods were applicable for qualitative and quantitative analysis for biotech maize event 3272 and LY 038.

  8. Analytical Validation of a Portable Mass Spectrometer Featuring Interchangeable, Ambient Ionization Sources for High Throughput Forensic Evidence Screening

    Science.gov (United States)

    Lawton, Zachary E.; Traub, Angelica; Fatigante, William L.; Mancias, Jose; O'Leary, Adam E.; Hall, Seth E.; Wieland, Jamie R.; Oberacher, Herbert; Gizzi, Michael C.; Mulligan, Christopher C.

    2017-06-01

    Forensic evidentiary backlogs are indicative of the growing need for cost-effective, high-throughput instrumental methods. One such emerging technology that shows high promise in meeting this demand while also allowing on-site forensic investigation is portable mass spectrometric (MS) instrumentation, particularly that which enables the coupling to ambient ionization techniques. While the benefits of rapid, on-site screening of contraband can be anticipated, the inherent legal implications of field-collected data necessitates that the analytical performance of technology employed be commensurate with accepted techniques. To this end, comprehensive analytical validation studies are required before broad incorporation by forensic practitioners can be considered, and are the focus of this work. Pertinent performance characteristics such as throughput, selectivity, accuracy/precision, method robustness, and ruggedness have been investigated. Reliability in the form of false positive/negative response rates is also assessed, examining the effect of variables such as user training and experience level. To provide flexibility toward broad chemical evidence analysis, a suite of rapidly-interchangeable ion sources has been developed and characterized through the analysis of common illicit chemicals and emerging threats like substituted phenethylamines. [Figure not available: see fulltext.

  9. Analytical Validation of a Portable Mass Spectrometer Featuring Interchangeable, Ambient Ionization Sources for High Throughput Forensic Evidence Screening.

    Science.gov (United States)

    Lawton, Zachary E; Traub, Angelica; Fatigante, William L; Mancias, Jose; O'Leary, Adam E; Hall, Seth E; Wieland, Jamie R; Oberacher, Herbert; Gizzi, Michael C; Mulligan, Christopher C

    2017-06-01

    Forensic evidentiary backlogs are indicative of the growing need for cost-effective, high-throughput instrumental methods. One such emerging technology that shows high promise in meeting this demand while also allowing on-site forensic investigation is portable mass spectrometric (MS) instrumentation, particularly that which enables the coupling to ambient ionization techniques. While the benefits of rapid, on-site screening of contraband can be anticipated, the inherent legal implications of field-collected data necessitates that the analytical performance of technology employed be commensurate with accepted techniques. To this end, comprehensive analytical validation studies are required before broad incorporation by forensic practitioners can be considered, and are the focus of this work. Pertinent performance characteristics such as throughput, selectivity, accuracy/precision, method robustness, and ruggedness have been investigated. Reliability in the form of false positive/negative response rates is also assessed, examining the effect of variables such as user training and experience level. To provide flexibility toward broad chemical evidence analysis, a suite of rapidly-interchangeable ion sources has been developed and characterized through the analysis of common illicit chemicals and emerging threats like substituted phenethylamines. Graphical Abstract ᅟ.

  10. A Validated Analytical Model for Availability Prediction of IPTV Services in VANETs

    Directory of Open Access Journals (Sweden)

    Bernd E. Wolfinger

    2014-12-01

    Full Text Available In vehicular ad hoc networks (VANETs, besides the original applications typically related to traffic safety, we nowadays can observe an increasing trend toward infotainment applications, such as IPTV services. Quality of experience (QoE, as observed by the end users of IPTV, is highly important to guarantee adequate user acceptance for the service. In IPTV, QoE is mainly determined by the availability of TV channels for the users. This paper presents an efficient and rather generally applicable analytical model that allows one to predict the blocking probability of TV channels, both for channel-switching-induced, as well as for handover-induced blocking events. We present the successful validation of the model by means of simulation, and we introduce a new measure for QoE. Numerous case studies illustrate how the analytical model and our new QoE measure can be applied successfully for the dimensioning of IPTV systems, taking into account the QoE requirements of the IPTV service users in strongly diverse traffic scenarios.

  11. AN ANALYTICAL METHOD FOR CHEMICAL SPECIATION OF SELENIUM IN SOIL

    Directory of Open Access Journals (Sweden)

    Constantin Luca

    2010-10-01

    Full Text Available Selenium is an essential microelement, sometimes redoubtable, through its beneficial role - risk depending on its concentration in the food chain, at low dose is an important nutrient in the life of humans and animals, contrary at high doses, it becomes toxic. Selenium may be find itself in the environment (soil, sediment, water in many forms (oxidized, reduced, organometallic which determine their mobility and toxicity. Determination of chemical speciation (identification of different chemical forms provides much more complete information for a better understanding of the behavior and the potential impact on the environment. In this work we present the results of methodological research on the extraction of sequential forms of selenium in the soil and the coupling of analytical methods capable of identifying very small amounts of selenium in soils An efficient scheme of sequential extractions forms of selenium (SES consisting in atomic absorption spectrometry coupled with hydride generation (HGAAS has been developed into five experimental steps, detailed in the paper. This operational scheme has been applied to the analysis of chemical speciation in the following areas: the Bărăgan Plain and Central Dobrogea of Romania.

  12. Analytical method to estimate resin cement diffusion into dentin

    Science.gov (United States)

    de Oliveira Ferraz, Larissa Cristina; Ubaldini, Adriana Lemos Mori; de Oliveira, Bruna Medeiros Bertol; Neto, Antonio Medina; Sato, Fracielle; Baesso, Mauro Luciano; Pascotto, Renata Corrêa

    2016-05-01

    This study analyzed the diffusion of two resin luting agents (resin cements) into dentin, with the aim of presenting an analytical method for estimating the thickness of the diffusion zone. Class V cavities were prepared in the buccal and lingual surfaces of molars (n=9). Indirect composite inlays were luted into the cavities with either a self-adhesive or a self-etch resin cement. The teeth were sectioned bucco-lingually and the cement-dentin interface was analyzed by using micro-Raman spectroscopy (MRS) and scanning electron microscopy. Evolution of peak intensities of the Raman bands, collected from the functional groups corresponding to the resin monomer (C-O-C, 1113 cm-1) present in the cements, and the mineral content (P-O, 961 cm-1) in dentin were sigmoid shaped functions. A Boltzmann function (BF) was then fitted to the peaks encountered at 1113 cm-1 to estimate the resin cement diffusion into dentin. The BF identified a resin cement-dentin diffusion zone of 1.8±0.4 μm for the self-adhesive cement and 2.5±0.3 μm for the self-etch cement. This analysis allowed the authors to estimate the diffusion of the resin cements into the dentin. Fitting the MRS data to the BF contributed to and is relevant for future studies of the adhesive interface.

  13. NIOSH Manual of Analytical Methods (third edition). Fourth supplement

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-15

    The NIOSH Manual of Analytical Methods, 3rd edition, was updated for the following chemicals: allyl-glycidyl-ether, 2-aminopyridine, aspartame, bromine, chlorine, n-butylamine, n-butyl-glycidyl-ether, carbon-dioxide, carbon-monoxide, chlorinated-camphene, chloroacetaldehyde, p-chlorophenol, crotonaldehyde, 1,1-dimethylhydrazine, dinitro-o-cresol, ethyl-acetate, ethyl-formate, ethylenimine, sodium-fluoride, hydrogen-fluoride, cryolite, sodium-hexafluoroaluminate, formic-acid, hexachlorobutadiene, hydrogen-cyanide, hydrogen-sulfide, isopropyl-acetate, isopropyl-ether, isopropyl-glycidyl-ether, lead, lead-oxide, maleic-anhydride, methyl-acetate, methyl-acrylate, methyl-tert-butyl ether, methyl-cellosolve-acetate, methylcyclohexanol, 4,4'-methylenedianiline, monomethylaniline, monomethylhydrazine, nitric-oxide, p-nitroaniline, phenyl-ether, phenyl-ether-biphenyl mixture, phenyl-glycidyl-ether, phenylhydrazine, phosphine, ronnel, sulfuryl-fluoride, talc, tributyl-phosphate, 1,1,2-trichloro-1,2,2-trifluoroethane, trimellitic-anhydride, triorthocresyl-phosphate, triphenyl-phosphate, and vinyl-acetate.

  14. Analytical methods for waste minimisation in the convenience food industry.

    Science.gov (United States)

    Darlington, R; Staikos, T; Rahimifard, S

    2009-04-01

    Waste creation in some sectors of the food industry is substantial, and while much of the used material is non-hazardous and biodegradable, it is often poorly dealt with and simply sent to landfill mixed with other types of waste. In this context, overproduction wastes were found in a number of cases to account for 20-40% of the material wastes generated by convenience food manufacturers (such as ready-meals and sandwiches), often simply just to meet the challenging demands placed on the manufacturer due to the short order reaction time provided by the supermarkets. Identifying specific classes of waste helps to minimise their creation, through consideration of what the materials constitute and why they were generated. This paper aims to provide means by which food industry wastes can be identified, and demonstrate these mechanisms through a practical example. The research reported in this paper investigated the various categories of waste and generated three analytical methods for the support of waste minimisation activities by food manufacturers. The waste classifications and analyses are intended to complement existing waste minimisation approaches and are described through consideration of a case study convenience food manufacturer that realised significant financial savings through waste measurement, analysis and reduction.

  15. Development and Validation of a Dissolution Test Method for ...

    African Journals Online (AJOL)

    Purpose: To develop and validate a dissolution test method for dissolution release of artemether and lumefantrine from tablets. Methods: A single dissolution method for evaluating the in vitro release of artemether and lumefantrine from tablets was developed and validated. The method comprised of a dissolution medium of ...

  16. Desenvolvimento e validação de método analítico para nistatina creme vaginal por cromatografia líquida de alta eficiência Development and validation of an analytical method for Nystatin vaginal cream by high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Zênia Maria Maciel Lavra

    2008-12-01

    1.0 mL/minute and wavelength of 305 nm. The validated method showed to be accurate, precise, robust, linear and specific, in addition to being fast and practical, able to be used for analytic dosing of nystatin vaginal cream.

  17. Validación del método analítico para el control de la calidad y el estudio de estabilidad del neolimpilen Validation of the analytical method for the quality control and the stability study of neolimpilem

    Directory of Open Access Journals (Sweden)

    Caridad M García Peña

    2004-08-01

    significativas. El método resultó específico, lineal, preciso y exacto.The analytical method developed for the quality control and for the stability study in the quantification of hydroxypropylmethylcellulose and sodium laurisulfate was validated by spectrophotometry with ultraviolet detection at 635 and 650 nm, respectively. Besides, the analytical results of the stability study conducted in the solution for cleaning and conservating rigid contact lens (neolimpilen are presented. Three batches packed in two different flasks were used to carry out the study by accelerated stability and shelf life in order to prove the phsyical and chemical stability of the solution at room temperature for 24 months. In the validation of hydroxypropylmethylcellulose, teh calibration curve in the range from 0.06 to 0.l8 mg/mL showed a lineal behavior with a correlation coefficient equal to 0.99581. The statistical test for the interval and the slope was not significant. A recovery of 99.8 % was obtained in the studied concentration range and Cochran (G and Student's (t tests were not indicative. The variation coefficient in the repeatabililty was 0.9 % for 10 tested replicas,. whereas Fischer and Student's tests were not significant in the reproducibility. The method proved to be specific, lineal, precise and exact. In the validation of sodium laurisulfate the calibration curve in the range 1.44 -3.0 mg/mL behaved in a lineal way with a correlation coefficient equal to 0.99036. The statistical test for the interval and the slope was not signficant. A recovery of 99.9% was attained in the studied concentration range and Cochran (G and Student's (t tests were not significant. The method proved to be specific, lineal, precise and exact.

  18. The Validation of Atomic Absorption Spectrometry (AAS) Method for the Determination of Cr, Cu and Pb

    International Nuclear Information System (INIS)

    Purwanto, A.; Supriyanto, C.; Samin P

    2007-01-01

    The validation of analytical method of atomic absorption spectrometry for the determination of Cr, Cu and Pb by using certified reference materials (CRM) have been carried out. The validation of analytical method was done by measurement of precision, accuracy, bias, % D and % RSD by analysis of chromium (Cr), Copper (Cu), and Lead (Pb) elements in CRM samples. Soil-7 is weighted and dissolved 0.3337 gram to use the bomb digester with concentrated nitric acid, perchloric acid, fluoric acid, and than solution to vinal volume is 10 mL with aquabidest. The validity of instrument atomic absorption spectrometer still valid with obtained of accuracy is 95.85 % and precision is 2.86 for Cr.; 103.32 % and 0.45 for Cu., 114.14 % and 9.89 for Pb. The validation of analytical method showed that with obtained of the content of Cr, Cu and Pb elements is 57.51, 11.37 and 68.49 μg/g., this result is still in the range concentration of certificate. (author)

  19. Evaluation of FTIR-based analytical methods for the analysis of simulated wastes

    International Nuclear Information System (INIS)

    Rebagay, T.V.; Cash, R.J.; Dodd, D.A.; Lockrem, L.L.; Meacham, J.E.; Winkelman, W.D.

    1994-01-01

    Three FTIR-based analytical methods that have potential to characterize simulated waste tank materials have been evaluated. These include: (1) fiber optics, (2) modular transfer optic using light guides equipped with non-contact sampling peripherals, and (3) photoacoustic spectroscopy. Pertinent instrumentation and experimental procedures for each method are described. The results show that the near-infrared (NIR) region of the infrared spectrum is the region of choice for the measurement of moisture in waste simulants. Differentiation of the NIR spectrum, as a preprocessing steps, will improve the analytical result. Preliminary data indicate that prominent combination bands of water and the first overtone band of the ferrocyanide stretching vibration may be utilized to measure water and ferrocyanide species simultaneously. Both near-infrared and mid-infrared spectra must be collected, however, to measure ferrocyanide species unambiguously and accurately. For ease of sample handling and the potential for field or waste tank deployment, the FTIR-Fiber Optic method is preferred over the other two methods. Modular transfer optic using light guides and photoacoustic spectroscopy may be used as backup systems and for the validation of the fiber optic data

  20. An analytical method for the calculation of static characteristics of linear step motors for control rod drives in nuclear reactors

    International Nuclear Information System (INIS)

    Khan, S.H.; Ivanov, A.A.

    1995-01-01

    An analytical method for calculating static characteristics of linear dc step motors (LSM) is described. These multiphase passive-armature motors are now being developed for control rod drives (CRD) in large nuclear reactors. The static characteristics of such LSM is defined by the variation of electromagnetic force with armature displacement and it determines motor performance in its standing and dynamic modes of operation. The proposed analytical technique for calculating this characteristic is based on the permeance analysis method applied to phase magnetic circuits of LSM. Reluctances of various parts of phase magnetic circuit is calculated analytically by assuming probable flux paths and by taking into account complex nature of magnetic field distribution in it. For given armature positions stator and armature iron saturations are taken into account by an efficient iterative algorithm which gives fast convergence. The method is validated by comparing theoretical results with experimental ones which shows satisfactory agreement for small stator currents and weak iron saturation

  1. Fuel Cycle Externalities: Analytical Methods and Issues, Report 2

    International Nuclear Information System (INIS)

    Barnthouse, L.W.; Cada, G.F.; Cheng, M.-D.; Easterly, C.E.; Kroodsma, R.L.; Lee, R.; Shriner, D.S.; Tolbert, V.R.; Turner, R.S.

    1994-01-01

    that also have not been fully addressed. This document contains two types of papers that seek to fill part of this void. Some of the papers describe analytical methods that can be applied to one of the five steps of the damage function approach. The other papers discuss some of the complex issues that arise in trying to estimate externalities. This report, the second in a series of eight reports, is part of a joint study by the U.S. Department of Energy (DOE) and the Commission of the European Communities (EC)* on the externalities of fuel cycles. Most of the papers in this report were originally written as working papers during the initial phases of this study. The papers provide descriptions of the (non-radiological) atmospheric dispersion modeling that the study uses; reviews much of the relevant literature on ecological and health effects, and on the economic valuation of those impacts; contains several papers on some of the more complex and contentious issues in estimating externalities; and describes a method for depicting the quality of scientific information that a study uses. The analytical methods and issues that this report discusses generally pertain to more than one of the fuel cycles, though not necessarily to all of them. The report is divided into six parts, each one focusing on a different subject area

  2. Estimating Fuel Cycle Externalities: Analytical Methods and Issues, Report 2

    Energy Technology Data Exchange (ETDEWEB)

    Barnthouse, L.W.; Cada, G.F.; Cheng, M.-D.; Easterly, C.E.; Kroodsma, R.L.; Lee, R.; Shriner, D.S.; Tolbert, V.R.; Turner, R.S.

    1994-07-01

    of complex issues that also have not been fully addressed. This document contains two types of papers that seek to fill part of this void. Some of the papers describe analytical methods that can be applied to one of the five steps of the damage function approach. The other papers discuss some of the complex issues that arise in trying to estimate externalities. This report, the second in a series of eight reports, is part of a joint study by the U.S. Department of Energy (DOE) and the Commission of the European Communities (EC)* on the externalities of fuel cycles. Most of the papers in this report were originally written as working papers during the initial phases of this study. The papers provide descriptions of the (non-radiological) atmospheric dispersion modeling that the study uses; reviews much of the relevant literature on ecological and health effects, and on the economic valuation of those impacts; contains several papers on some of the more complex and contentious issues in estimating externalities; and describes a method for depicting the quality of scientific information that a study uses. The analytical methods and issues that this report discusses generally pertain to more than one of the fuel cycles, though not necessarily to all of them. The report is divided into six parts, each one focusing on a different subject area.

  3. Validating and Determining the Weight of Items Used for Evaluating Clinical Governance Implementation Based on Analytic Hierarchy Process Model

    Directory of Open Access Journals (Sweden)

    Elaheh Hooshmand

    2015-10-01

    Full Text Available Background The purpose of implementing a system such as Clinical Governance (CG is to integrate, establish and globalize distinct policies in order to improve quality through increasing professional knowledge and the accountability of healthcare professional toward providing clinical excellence. Since CG is related to change, and change requires money and time, CG implementation has to be focused on priority areas that are in more dire need of change. The purpose of the present study was to validate and determine the significance of items used for evaluating CG implementation. Methods The present study was descriptive-quantitative in method and design. Items used for evaluating CG implementation were first validated by the Delphi method and then compared with one another and ranked based on the Analytical Hierarchy Process (AHP model. Results The items that were validated for evaluating CG implementation in Iran include performance evaluation, training and development, personnel motivation, clinical audit, clinical effectiveness, risk management, resource allocation, policies and strategies, external audit, information system management, research and development, CG structure, implementation prerequisites, the management of patients’ non-medical needs, complaints and patients’ participation in the treatment process. The most important items based on their degree of significance were training and development, performance evaluation, and risk management. The least important items included the management of patients’ non-medical needs, patients’ participation in the treatment process and research and development. Conclusion The fundamental requirements of CG implementation included having an effective policy at national level, avoiding perfectionism, using the expertise and potentials of the entire country and the coordination of this model with other models of quality improvement such as accreditation and patient safety.

  4. Analytical method of waste allocation in waste management systems: Concept, method and case study

    International Nuclear Information System (INIS)

    Bergeron, Francis C.

    2017-01-01

    Waste is not a rejected item to dispose anymore but increasingly a secondary resource to exploit, influencing waste allocation among treatment operations in a waste management (WM) system. The aim of this methodological paper is to present a new method for the assessment of the WM system, the “analytical method of the waste allocation process” (AMWAP), based on the concept of the “waste allocation process” defined as the aggregation of all processes of apportioning waste among alternative waste treatment operations inside or outside the spatial borders of a WM system. AMWAP contains a conceptual framework and an analytical approach. The conceptual framework includes, firstly, a descriptive model that focuses on the description and classification of the WM system. It includes, secondly, an explanatory model that serves to explain and to predict the operation of the WM system. The analytical approach consists of a step-by-step analysis for the empirical implementation of the conceptual framework. With its multiple purposes, AMWAP provides an innovative and objective modular method to analyse a WM system which may be integrated in the framework of impact assessment methods and environmental systems analysis tools. Its originality comes from the interdisciplinary analysis of the WAP and to develop the conceptual framework. AMWAP is applied in the framework of an illustrative case study on the household WM system of Geneva (Switzerland). It demonstrates that this method provides an in-depth and contextual knowledge of WM. - Highlights: • The study presents a new analytical method based on the waste allocation process. • The method provides an in-depth and contextual knowledge of the waste management system. • The paper provides a reproducible procedure for professionals, experts and academics. • It may be integrated into impact assessment or environmental system analysis tools. • An illustrative case study is provided based on household waste

  5. Analytic Method to Estimate Particle Acceleration in Flux Ropes

    Science.gov (United States)

    Guidoni, S. E.; Karpen, J. T.; DeVore, C. R.

    2015-01-01

    The mechanism that accelerates particles to the energies required to produce the observed high-energy emission in solar flares is not well understood. Drake et al. (2006) proposed a kinetic mechanism for accelerating electrons in contracting magnetic islands formed by reconnection. In this model, particles that gyrate around magnetic field lines transit from island to island, increasing their energy by Fermi acceleration in those islands that are contracting. Based on these ideas, we present an analytic model to estimate the energy gain of particles orbiting around field lines inside a flux rope (2.5D magnetic island). We calculate the change in the velocity of the particles as the flux rope evolves in time. The method assumes a simple profile for the magnetic field of the evolving island; it can be applied to any case where flux ropes are formed. In our case, the flux-rope evolution is obtained from our recent high-resolution, compressible 2.5D MHD simulations of breakout eruptive flares. The simulations allow us to resolve in detail the generation and evolution of large-scale flux ropes as a result of sporadic and patchy reconnection in the flare current sheet. Our results show that the initial energy of particles can be increased by 2-5 times in a typical contracting island, before the island reconnects with the underlying arcade. Therefore, particles need to transit only from 3-7 islands to increase their energies by two orders of magnitude. These macroscopic regions, filled with a large number of particles, may explain the large observed rates of energetic electron production in flares. We conclude that this mechanism is a promising candidate for electron acceleration in flares, but further research is needed to extend our results to 3D flare conditions.

  6. Random Qualitative Validation: A Mixed-Methods Approach to Survey Validation

    Science.gov (United States)

    Van Duzer, Eric

    2012-01-01

    The purpose of this paper is to introduce the process and value of Random Qualitative Validation (RQV) in the development and interpretation of survey data. RQV is a method of gathering clarifying qualitative data that improves the validity of the quantitative analysis. This paper is concerned with validity in relation to the participants'…

  7. Differentiating between analytical and diagnostic performance evaluation with a focus on the method comparison study and identification of bias.

    Science.gov (United States)

    Flatland, Bente; Friedrichs, Kristen R; Klenner, Stefanie

    2014-12-01

    Prior to introduction of a new method to the diagnostic laboratory, analytical performance must be validated to ensure operation within the manufacturer's specifications and/or within predetermined quality requirements. In addition, the new method may require diagnostic performance assessment to ensure it differentiates between diseased and nondiseased individuals as intended. These 2 phases of assessment, while complementary, are not equivalent and require a different set of experiments, statistical analyses, and interpretation. Studies of analytical performance typically include a method comparison experiment, the purpose of which is to identify bias (inaccuracy) of the "test" (or "index") method (new method) relative to a "comparative method" (established method). Analysis of method comparison data is facilitated by commercial software programs that present the statistical significance of identified bias; however, the clinical relevance of any bias also should be considered. Studies of diagnostic performance should not be pursued until analytical performance is fully characterized and may not be required for well-established tests or for those for which results are nonspecific (ie, not referable to a specific disease or condition). Diagnostic performance assessment may include assessment of sensitivity, specificity, predictive values, odds ratios, and/or likelihood ratios. The purpose of this review is to clarify differences between the assessment of analytical and diagnostic performance, and to explore the method comparison study and bias assessment from a perspective not addressed in prior veterinary articles. © 2014 American Society for Veterinary Clinical Pathology.

  8. A Comparison of Two Approaches for the Ruggedness Testing of an Analytical Method

    International Nuclear Information System (INIS)

    Maestroni, Britt

    2016-01-01

    As part of an initiative under the “Red Analitica de Latino America y el Caribe” (RALACA) network the FAO/IAEA Food and Environmental Protection Laboratory validated a multi-residue method for pesticides in potato. One of the parameters to be assessed was the intra laboratory robustness or ruggedness. The objective of this work was to implement a worked example for RALACA laboratories to test for the robustness (ruggedness) of an analytical method. As a conclusion to this study, it is evident that there is a need for harmonization of the definition of the terms robustness/ruggedness, the limits, the methodology and the statistical treatment of the generated data. A worked example for RALACA laboratories to test for the robustness (ruggedness) of an analytical method will soon be posted on the RALACA website (www.red-ralaca.net). This study was carried out with collaborators from LVA (Austria), University of Antwerp (Belgium), University of Leuwen (The Netherlands), Universidad de la Republica (Uruguay) and Agilent technologies.

  9. Analytical Validation of the ReEBOV Antigen Rapid Test for Point-of-Care Diagnosis of Ebola Virus Infection

    Science.gov (United States)

    Cross, Robert W.; Boisen, Matthew L.; Millett, Molly M.; Nelson, Diana S.; Oottamasathien, Darin; Hartnett, Jessica N.; Jones, Abigal B.; Goba, Augustine; Momoh, Mambu; Fullah, Mohamed; Bornholdt, Zachary A.; Fusco, Marnie L.; Abelson, Dafna M.; Oda, Shunichiro; Brown, Bethany L.; Pham, Ha; Rowland, Megan M.; Agans, Krystle N.; Geisbert, Joan B.; Heinrich, Megan L.; Kulakosky, Peter C.; Shaffer, Jeffrey G.; Schieffelin, John S.; Kargbo, Brima; Gbetuwa, Momoh; Gevao, Sahr M.; Wilson, Russell B.; Saphire, Erica Ollmann; Pitts, Kelly R.; Khan, Sheik Humarr; Grant, Donald S.; Geisbert, Thomas W.; Branco, Luis M.; Garry, Robert F.

    2016-01-01

    Background. Ebola virus disease (EVD) is a severe viral illness caused by Ebola virus (EBOV). The 2013–2016 EVD outbreak in West Africa is the largest recorded, with >11 000 deaths. Development of the ReEBOV Antigen Rapid Test (ReEBOV RDT) was expedited to provide a point-of-care test for suspected EVD cases. Methods. Recombinant EBOV viral protein 40 antigen was used to derive polyclonal antibodies for RDT and enzyme-linked immunosorbent assay development. ReEBOV RDT limits of detection (LOD), specificity, and interference were analytically validated on the basis of Food and Drug Administration (FDA) guidance. Results. The ReEBOV RDT specificity estimate was 95% for donor serum panels and 97% for donor whole-blood specimens. The RDT demonstrated sensitivity to 3 species of Ebolavirus (Zaire ebolavirus, Sudan ebolavirus, and Bundibugyo ebolavirus) associated with human disease, with no cross-reactivity by pathogens associated with non-EBOV febrile illness, including malaria parasites. Interference testing exhibited no reactivity by medications in common use. The LOD for antigen was 4.7 ng/test in serum and 9.4 ng/test in whole blood. Quantitative reverse transcription–polymerase chain reaction testing of nonhuman primate samples determined the range to be equivalent to 3.0 × 105–9.0 × 108 genomes/mL. Conclusions. The analytical validation presented here contributed to the ReEBOV RDT being the first antigen-based assay to receive FDA and World Health Organization emergency use authorization for this EVD outbreak, in February 2015. PMID:27587634

  10. Analytical validity of a microRNA‐based assay for diagnosing indeterminate thyroid FNA smears from routinely prepared cytology slides

    Science.gov (United States)

    Benjamin, Hila; Schnitzer‐Perlman, Temima; Shtabsky, Alexander; VandenBussche, Christopher J.; Ali, Syed Z.; Kolar, Zdenek; Pagni, Fabio; Bar, Dganit

    2016-01-01

    BACKGROUND The majority of thyroid nodules are diagnosed using fine‐needle aspiration (FNA) biopsies. The authors recently described the clinical validation of a molecular microRNA‐based assay, RosettaGX Reveal, which can diagnose thyroid nodules as benign or suspicious using a single stained FNA smear. This paper describes the analytical validation of the assay. METHODS More than 800 FNA slides were tested, including slides stained with Romanowsky‐type and Papanicolaou stains. The assay was examined for the following features: intranodule concordance, effect of stain type, minimal acceptable RNA amounts, performance on low numbers of thyroid cells, effect of time since sampling, and analytical sensitivity, specificity, and reproducibility. RESULTS The assay can be run on FNA slides for which as little as 1% of the cells are thyroid epithelial cells or from which only 5 ng of RNA have been extracted. Samples composed entirely of blood failed quality control and were not classified. Stain type did not affect performance. All slides were stored at room temperature. However, the length of time between FNA sampling and processing did not affect assay performance. There was a high level of concordance between laboratories (96%), and the concordance for slides created from the same FNA pass was 93%. CONCLUSIONS The microRNA‐based assay was robust to various physical processing conditions and to differing sample characteristics. Given the assay's performance, robustness, and use of routinely prepared FNA slides, it has the potential to provide valuable aid for physicians in the diagnosis of thyroid nodules. Cancer Cytopathol 2016;124:711–21. © 2016 Rosetta Genomics. Cancer Cytopathology published by Wiley Periodicals, Inc. on behalf of American Cancer Society. PMID:27223344

  11. Analytical method by high resolution liquid chromatography for the determination of carbamazepine in human plasma

    International Nuclear Information System (INIS)

    Jimenez Aleman, Narda M; Calero Carbonell, Jorge E; Padron Yaquis, Alejandro S; Izquierdo Lozano, Julio C

    2007-01-01

    One of the requirements to develop the studies of bioavailability and bioequivalence is to have analytic methodologies validated for the work with samples in biological fluids. A method was developed by high resolution liquid chromatography for the determination of carbamazepine in human plasma. A mixture of hydrogen phosphate of sodium: acetonitrile (65:35) adjusted to pH= 3.3 with phosphoric acid, flow of 1.2 mL/min and ultraviolet detection at 210 nm, was used as mobile phase. Propylparabene was used as an internal standard. According to the established regulations for the validation of the methods in biological fluids, the following parameters were studied: stability of the samples, lineality, specificity, precision, accuracy and limit of detection and quantification. The method proved to be specific and sensitive with a detection and quantification limit of 0.9 and 1.0 ng, respectively. The method was lineal, precise and exact in the range of concentrations of 1. 07 at 12.67 μg/mL. The mean recovery was not statistically different from 100.0 %. The analito in the proposed biological matrix remained in the studied period. The methodology described in this work is applied in our case to the study that evaluates the bioavailability and bioequivalence of a Cuban formulation of carbamazepine in healthy volunteers. (Author)

  12. A long-term validation of the modernised DC-ARC-OES solid-sample method

    Energy Technology Data Exchange (ETDEWEB)

    Florian, K. [Dept. of Chemistry, Technical University of Kosice (Slovakia); Hassler, J.; Foerster, O. [Elektroschmelzwerk GmbH, Kempten (Germany)

    2001-12-01

    The validation procedure based on ISO 17 025 standard has been used to study and illustrate both the long-term stability of the calibration process of the DC-ARC solid sample spectrometric method and the main validation criteria of the method. In the calculation of the validation characteristics depending on the linearity(calibration), also the fulfilment of predetermining criteria such as normality and homoscedasticity was checked. In order to decide whether there are any trends in the time-variation of the analytical signal or not, also the Neumann test of trend was applied and evaluated. Finally, a comparison with similar validation data of the ETV-ICP-OES method was carried out. (orig.)

  13. Sensitive and validated spectrophotometric methods for the ...

    African Journals Online (AJOL)

    The methods involve the addition of a known excess of NBS to PNT in HCl medium followed by estimation of the unreacted oxidant by two reaction schemes involving the use of iron(II) and thiocyanate (method A) or tiron (method B). In both methods, the absorbance is found to decrease linearly with PNT concentration.

  14. Sulfathiazole: analytical methods for quantification in seawater and macroalgae.

    Science.gov (United States)

    Leston, Sara; Nebot, Carolina; Nunes, Margarida; Cepeda, Alberto; Pardal, Miguel Ângelo; Ramos, Fernando

    2015-01-01

    The awareness of the interconnection between pharmaceutical residues, human health, and aquaculture has highlighted the concern with the potential harmful effects it can induce. Furthermore, to better understand the consequences more research is needed and to achieve that new methodologies on the detection and quantification of pharmaceuticals are necessary. Antibiotics are a major class of drugs included in the designation of emerging contaminants, representing a high risk to natural ecosystems. Among the most prescribed are sulfonamides, with sulfathiazole being the selected compound to be investigated in this study. In the environment, macroalgae are an important group of producers, continuously exposed to contaminants, with a significant role in the trophic web. Due to these characteristics are already under scope for the possibility of being used as bioindicators. The present study describes two new methodologies based on liquid chromatography for the determination of sulfathiazole in seawater and in the green macroalgae Ulva lactuca. Results show both methods were validated according to international standards, with MS/MS detection showing more sensitivity as expected with LODs of 2.79ng/g and 1.40ng/mL for algae and seawater, respectively. As for UV detection the values presented were respectively 2.83μg/g and 2.88μg/mL, making it more suitable for samples originated in more contaminated sites. The methods were also applied to experimental data with success with results showing macroalgae have potential use as indicators of contamination. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Validating and determining the weight of items used for evaluating clinical governance implementation based on analytic hierarchy process model.

    Science.gov (United States)

    Hooshmand, Elaheh; Tourani, Sogand; Ravaghi, Hamid; Vafaee Najar, Ali; Meraji, Marziye; Ebrahimipour, Hossein

    2015-04-08

    The purpose of implementing a system such as Clinical Governance (CG) is to integrate, establish and globalize distinct policies in order to improve quality through increasing professional knowledge and the accountability of healthcare professional toward providing clinical excellence. Since CG is related to change, and change requires money and time, CG implementation has to be focused on priority areas that are in more dire need of change. The purpose of the present study was to validate and determine the significance of items used for evaluating CG implementation. The present study was descriptive-quantitative in method and design. Items used for evaluating CG implementation were first validated by the Delphi method and then compared with one another and ranked based on the Analytical Hierarchy Process (AHP) model. The items that were validated for evaluating CG implementation in Iran include performance evaluation, training and development, personnel motivation, clinical audit, clinical effectiveness, risk management, resource allocation, policies and strategies, external audit, information system management, research and development, CG structure, implementation prerequisites, the management of patients' non-medical needs, complaints and patients' participation in the treatment process. The most important items based on their degree of significance were training and development, performance evaluation, and risk management. The least important items included the management of patients' non-medical needs, patients' participation in the treatment process and research and development. The fundamental requirements of CG implementation included having an effective policy at national level, avoiding perfectionism, using the expertise and potentials of the entire country and the coordination of this model with other models of quality improvement such as accreditation and patient safety. © 2015 by Kerman University of Medical Sciences.

  16. Application of analytical quality by design principles for the determination of alkyl p-toluenesulfonates impurities in Aprepitant by HPLC. Validation using total-error concept.

    Science.gov (United States)

    Zacharis, Constantinos K; Vastardi, Elli

    2018-02-20

    In the research presented we report the development of a simple and robust liquid chromatographic method for the quantification of two genotoxic alkyl sulphonate impurities (namely methyl p-toluenesulfonate and isopropyl p-toluenesulfonate) in Aprepitant API substances using the Analytical Quality by Design (AQbD) approach. Following the steps of AQbD protocol, the selected critical method attributes (CMAs) were the separation criterions between the critical peak pairs, the analysis time and the peak efficiencies of the analytes. The critical method parameters (CMPs) included the flow rate, the gradient slope and the acetonitrile content at the first step of the gradient elution program. Multivariate experimental designs namely Plackett-Burman and Box-Behnken designs were conducted sequentially for factor screening and optimization of the method parameters. The optimal separation conditions were estimated using the desirability function. The method was fully validated in the range of 10-200% of the target concentration limit of the analytes using the "total error" approach. Accuracy profiles - a graphical decision making tool - were constructed using the results of the validation procedures. The β-expectation tolerance intervals did not exceed the acceptance criteria of±10%, meaning that 95% of future results will be included in the defined bias limits. The relative bias ranged between - 1.3-3.8% for both analytes, while the RSD values for repeatability and intermediate precision were less than 1.9% in all cases. The achieved limit of detection (LOD) and the limit of quantification (LOQ) were adequate for the specific purpose and found to be 0.02% (corresponding to 48μgg -1 in sample) for both methyl and isopropyl p-toluenesulfonate. As proof-of-concept, the validated method was successfully applied in the analysis of several Aprepitant batches indicating that this methodology could be used for routine quality control analyses. Copyright © 2017 Elsevier B

  17. Analytical support of plant specific SAMG development validation of SAMG using MELCOR 1.8.5

    International Nuclear Information System (INIS)

    Duspiva, Jiri

    2006-01-01

    They are two NPPs in operation in Czech Republic. Both of NPPs operated in CR have already implemented EOPs, developed under collaboration with the WESE. The project on SAMG development has started and follows the previous one for EOPs also with the WESE as the leading organization. Plant specific SAMGs for the Temelin as well as Dukovany NPPs are based on the WOG generic SAMGs. The analytical support of plant specific SAMGs development is performed by the NRI Rez within the validation process. Basic conditions as well as their filling by NRI Rez are focused on analyst, analytical tools and their applications. More detail description is attended to the approach of the preparation of the MELCOR code application to the evaluation of hydrogen risk, validation of recent set of hydrogen passive autocatalytic recombiners and definition of proposals to amend system of hydrogen removal. Such kind of parametric calculations will request to perform very wide set of runs. It could not be possible with the whole plant model and decoupling of such calculation with storing of mass and energy sources into the containment is only one way. The example of this decoupling for the LOCA scenario is shown. It includes seven sources - heat losses from primary and secondary circuits, fluid blowndown through cold leg break, fission products blowndown through cold leg break, fluid blowndown through break in reactor pressure vessel bottom head, fission products through break in reactor pressure vessel bottom head, melt ejection from reactor pressure vessel to cavity and gas masses and heat losses from corium in cavity. The stand alone containment analysis was tested in two configurations - with or without taking of fission products into account. Testing showed very good agreement of all calculations until lower head failure and acceptable agreement after that. Also some problematic features appeared. The stand alone test with fission product was possible only after the changes in source code

  18. Method development and validation for determination of antihemolytic activity of eculizumab (Soliris

    Directory of Open Access Journals (Sweden)

    E. Yu. Prudnikova

    2016-01-01

    Full Text Available Bioanalytical methods are applied at the development and test of drugs as well as at the step of pharmaceutic products issue. Drugs and excipients quality estimation is made by means of precise and reproducible methods. Accuracy and reproducibility of a method is established during validation which is obligatory for medicine registration. The principal task of method validation is experimental evidence of its suitability for the objectives to be achieved. Validation of bioanalytical methods is one of the elements of the whole medicine production validation [1, 2].The aim of research: to validate a method for determination of specific anti-hemolytic activity of eculizumab developed in LCC “IBC Generium”.Materials and methods: eculizumab, antibody-sensitized chicken erythrocytes, complement-containing human serum.Results. We demonstrated the specificity of the method and its correspondence to criteria of accuracy (103.0±1.4%, robustness (CV – 11.5%, repeatability (CV – (4.9±0.9%, reproducibility (CV – (3.5±0.4%, and linearity (k -1.0275; R2 – 0.9975 during validation. The system validity (equipment, materials, analytical operations and analyzed samples was confirmed for true results obtaining during validation.Results discussion. Experimental evidence of suitability of the method for eculizumab specific activity assessment was obtained in course of validation. The simplicity of the method allows obtaining accurate results in other laboratories. The developed method can be used not only for specific activity of Soliris determination but also for other pharmaceutical substances and drugs based on antibodies specific to human complement C5.

  19. Validation of a new analytical procedure for determination of residual solvents in [{sup 18}F]FDG by gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Flávia M.; Costa, Cassiano L.S.; Silva, Juliana B.; Ferreira, Soraya M.Z.M.D., E-mail: flaviabiomedica@yahoo.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (UPPR/CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Unidade de Pesquisa e Produção de Radiofármacos

    2017-07-01

    Fludeoxyglucose F 18 ([{sup 18}F]FDG) is the most used radiopharmaceutical for positron emission tomography, especially on oncology. Organic solvents such as ether, ethanol and acetonitrile might be used in the synthesis of [{sup 18}F]FDG; however, they might not be completely removed during purification steps. The determination of residual solvents in [{sup 18}F]FDG is required in the European Pharmacopoeia (EP) and the United States Pharmacopeia (USP) monographs. While the procedure described in the EP is quite general, the one described in the USP requires a long runtime (about 13 minutes). In this work a simple and fast (4-minute) analytical procedure was developed and validated for determination of residual solvents in [{sup 18}F]FDG. Analyses were carried out in a Perkin Elmer gas chromatograph equipped with a flame ionization detector. The separation was obtained on a 0.53-mm x 30 m fused-silica column. Validation included the evaluation of various parameters, such as: specificity, linearity and range, limits of detection and quantitation, precision (repeatability and intermediate precision), accuracy, and robustness. Results were found to be within acceptable limits, indicating the developed procedure is suitable for its intended application. Considering the short half-life of fluorine-18 (109.7 minutes), this new method could be a valuable alternative for routine quality control of [{sup 18}F]FDG. (author)

  20. Hanford environmental analytical methods: Methods as of March 1990. Volume 3, Appendix A2-I

    Energy Technology Data Exchange (ETDEWEB)

    Goheen, S.C.; McCulloch, M.; Daniel, J.L.

    1993-05-01

    This paper from the analytical laboratories at Hanford describes the method used to measure pH of single-shell tank core samples. Sludge or solid samples are mixed with deionized water. The pH electrode used combines both a sensor and reference electrode in one unit. The meter amplifies the input signal from the electrode and displays the pH visually.

  1. 40 CFR 141.25 - Analytical methods for radioactivity.

    Science.gov (United States)

    2010-07-01

    .... 141.25 Section 141.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Monitoring and Analytical Requirements... Spectrometry 901.1 p. 92 7120, 7120-97 D4785-93, 00a 4.5.2.3 Radioactive Strontium 89, 90 Radiochemical 905.0 p...

  2. Laser: a Tool for Optimization and Enhancement of Analytical Methods

    Energy Technology Data Exchange (ETDEWEB)

    Preisler, Jan [Iowa State Univ., Ames, IA (United States)

    1997-01-01

    In this work, we use lasers to enhance possibilities of laser desorption methods and to optimize coating procedure for capillary electrophoresis (CE). We use several different instrumental arrangements to characterize matrix-assisted laser desorption (MALD) at atmospheric pressure and in vacuum. In imaging mode, 488-nm argon-ion laser beam is deflected by two acousto-optic deflectors to scan plumes desorbed at atmospheric pressure via absorption. All absorbing species, including neutral molecules, are monitored. Interesting features, e.g. differences between the initial plume and subsequent plumes desorbed from the same spot, or the formation of two plumes from one laser shot are observed. Total plume absorbance can be correlated with the acoustic signal generated by the desorption event. A model equation for the plume velocity as a function of time is proposed. Alternatively, the use of a static laser beam for observation enables reliable determination of plume velocities even when they are very high. Static scattering detection reveals negative influence of particle spallation on MS signal. Ion formation during MALD was monitored using 193-nm light to photodissociate a portion of insulin ion plume. These results define the optimal conditions for desorbing analytes from matrices, as opposed to achieving a compromise between efficient desorption and efficient ionization as is practiced in mass spectrometry. In CE experiment, we examined changes in a poly(ethylene oxide) (PEO) coating by continuously monitoring the electroosmotic flow (EOF) in a fused-silica capillary during electrophoresis. An imaging CCD camera was used to follow the motion of a fluorescent neutral marker zone along the length of the capillary excited by 488-nm Ar-ion laser. The PEO coating was shown to reduce the velocity of EOF by more than an order of magnitude compared to a bare capillary at pH 7.0. The coating protocol was important, especially at an intermediate pH of 7.7. The increase of p

  3. Analytical solutions for solute transport in groundwater and riverine flow using Green's Function Method and pertinent coordinate transformation method

    Science.gov (United States)

    Sanskrityayn, Abhishek; Suk, Heejun; Kumar, Naveen

    2017-04-01

    In this study, analytical solutions of one-dimensional pollutant transport originating from instantaneous and continuous point sources were developed in groundwater and riverine flow using both Green's Function Method (GFM) and pertinent coordinate transformation method. Dispersion coefficient and flow velocity are considered spatially and temporally dependent. The spatial dependence of the velocity is linear, non-homogeneous and that of dispersion coefficient is square of that of velocity, while the temporal dependence is considered linear, exponentially and asymptotically decelerating and accelerating. Our proposed analytical solutions are derived for three different situations depending on variations of dispersion coefficient and velocity, respectively which can represent real physical processes occurring in groundwater and riverine systems. First case refers to steady solute transport situation in steady flow in which dispersion coefficient and velocity are only spatially dependent. The second case represents transient solute transport in steady flow in which dispersion coefficient is spatially and temporally dependent while the velocity is spatially dependent. Finally, the third case indicates transient solute transport in unsteady flow in which both dispersion coefficient and velocity are spatially and temporally dependent. The present paper demonstrates the concentration distribution behavior from a point source in realistically occurring flow domains of hydrological systems including groundwater and riverine water in which the dispersivity of pollutant's mass is affected by heterogeneity of the medium as well as by other factors like velocity fluctuations, while velocity is influenced by water table slope and recharge rate. Such capabilities give the proposed method's superiority about application of various hydrological problems to be solved over other previously existing analytical solutions. Especially, to author's knowledge, any other solution doesn

  4. Experimental Validation of a Risk Assessment Method

    NARCIS (Netherlands)

    Vriezekolk, E.; Etalle, Sandro; Wieringa, Roelf J.

    [Context and motivation] It is desirable that require- ment engineering methods are reliable, that is, that methods can be repeated with the same results. Risk assessments methods, however, often have low reliability when they identify risk mitigations for a sys- tem based on expert judgement.

  5. Analytical method for analysis of electromagnetic scattering from inhomogeneous spherical structures using duality principles

    Science.gov (United States)

    Kiani, M.; Abdolali, A.; Safari, M.

    2018-03-01

    In this article, an analytical approach is presented for the analysis of electromagnetic (EM) scattering from radially inhomogeneous spherical structures (RISSs) based on the duality principle. According to the spherical symmetry, similar angular dependencies in all the regions are considered using spherical harmonics. To extract the radial dependency, the system of differential equations of wave propagation toward the inhomogeneity direction is equated with the dual planar ones. A general duality between electromagnetic fields and parameters and scattering parameters of the two structures is introduced. The validity of the proposed approach is verified through a comprehensive example. The presented approach substitutes a complicated problem in spherical coordinate to an easy, well posed, and previously solved problem in planar geometry. This approach is valid for all continuously varying inhomogeneity profiles. One of the major advantages of the proposed method is the capability of studying two general and applicable types of RISSs. As an interesting application, a class of lens antenna based on the physical concept of the gradient refractive index material is introduced. The approach is used to analyze the EM scattering from the structure and validate strong performance of the lens.

  6. An analytical method for predicting the geometrical and optical properties of the human lens under accommodation

    Science.gov (United States)

    Sheil, Conor J.; Bahrami, Mehdi; Goncharov, Alexander V.

    2014-01-01

    We present an analytical method to describe the accommodative changes in the human crystalline lens. The method is based on the geometry-invariant lens model, in which the gradient-index (GRIN) iso-indicial contours are coupled to the external shape. This feature ensures that any given number of iso-indicial contours does not change with accommodation, which preserves the optical integrity of the GRIN structure. The coupling also enables us to define the GRIN structure if the radii and asphericities of the external lens surfaces are known. As an example, the accommodative changes in lenticular radii and central thickness were taken from the literature, while the asphericities of the external surfaces were derived analytically by adhering to the basic physical conditions of constant lens volume and its axial position. The resulting changes in lens geometry are consistent with experimental data, and the optical properties are in line with expected values for optical power and spherical aberration. The aim of the paper is to provide an anatomically and optically accurate lens model that is valid for 3 mm pupils and can be used as a new tool for better understanding of accommodation. PMID:24877022

  7. Recent Trends in Analytical Methods to Determine New Psychoactive Substances in Hair.

    Science.gov (United States)

    Kyriakou, Chrystalla; Pellegrini, Manuela; García-Algar, Oscar; Marinelli, Enrico; Zaami, Simona

    2017-01-01

    New Psychoactive Substances (NPS) belong to several chemical classes, including phenethylamines, piperazines, synthetic cathinones and synthetic cannabinoids. Development and validation of analytical methods for the determination of NPS both in traditional and alternative matrices is of crucial importance to study drug metabolism and to associate consumption to clinical outcomes and eventual intoxication symptoms. Among different biological matrices, hair is the one with the widest time window to investigate drug-related history and demonstrate past intake. The aim of this paper was to overview the trends of the rapidly evolving analytical methods for the determination of NPS in hair and the usefulness of these methods when applied to real cases. A number of rapid and sensitive methods for the determination of NPS in hair matrix has been recently published, most of them using liquid chromatography coupled to mass spectrometry. Hair digestion and subsequent solid phase extraction or liquid-liquid extraction were described as well as extraction in organic solvents. For most of the methods limits of quantification at picogram per milligram hair were obtained. The measured concentrations for most of the NPS in real samples were in the range of picograms of drug per milligram of hair. Interpretation of the results and lack of cut-off values for the discrimination between chronic consumption and occasional use or external contamination are still challenging. Methods for the determination of NPS in hair are continually emerging to include as many NPS as possible due to the great demand for their detection. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Validation Method of a Telecommunications Blackout Attack

    National Research Council Canada - National Science Library

    Amado, Joao; Nunes, Paulo

    2005-01-01

    This paper presents an evaluation method of telecommunications infrastructure vulnerabilities, allowing the identification of components that can be attacked in order to achieve a communications blackout...

  9. Validação em laboratório de método analítico para determinação do teor de adipato e ftalato de di-(2-etil-hexila utilizados como plastificantes em filmes flexíveis de PVC Validation in laboratory of the analytical method to determine di-(2-ethylhexyl phthalate and adipate utilized as plasticizers in pvc films

    Directory of Open Access Journals (Sweden)

    Andreia Artur Esteves

    2007-02-01

    Full Text Available The validation of analytical methods was carried out for di-(ethylhexyl phthalate (DEHP and adipate (DEHA the determination of in PVC films. The level of DEHP and DEHA in samples was determined by leaving the film in contact with n-heptane during 48 hours and analysis in a gas chromatograph (GC equipped with a flame ionization detector and fused silica column with 5% phenylmethyl silicone in the dimensions 30 m x 0.53 mm x 2.65 mm. The results for detection and the quantification limits were smaller than the restriction limits. The recovery rates of DEHP and DEHA were, respectively, 69.10 and 75.30 %.

  10. Validação de metodologia analítica para determinação de mercúrio total em amostras de urina por espectrometria de absorção atômica com geração de vapor frio (CV-AAS: estudo de caso Validation of an analytical method for the determination of total mercury in urine samples using cold vapor atomic absorption spectrometry (CV-AAS: case study

    Directory of Open Access Journals (Sweden)

    Sabine Neusatz Guilhen

    2010-01-01

    Full Text Available Mercury is a toxic metal used in a variety of substances over the course history. One of its more dubious uses is in dental amalgam restorations. It is possible to measure very small concentrations of this metal in the urine of exposed subjects by the cold vapor atomic absorption technique. The present work features the validation as an essential tool to confirm the suitability of the analytical method chosen to accomplish such determination. An initial analysis will be carried out in order to evaluate the environmental and occupational levels of exposure to mercury in 39 members of the auxiliary dental staff at public consulting rooms in the city of Araguaína (TO.

  11. Validated High Performance Liquid Chromatography Method for ...

    African Journals Online (AJOL)

    Purpose: To develop a simple, rapid and sensitive high performance liquid chromatography (HPLC) method for the determination of cefadroxil monohydrate in human plasma. Methods: Schimadzu HPLC with LC solution software was used with Waters Spherisorb, C18 (5 μm, 150mm × 4.5mm) column. The mobile phase ...

  12. Validação de métodos analíticos na quantificação de comprimidos de Captopril - comparação de metodologias para um programa de garantia de qualidade - DOI: 10.4025/actascihealthsci.v26i2.1590 Validation of analytical methods for quantifying captopril in tablets – a comparison of methodologies for a quality control program - DOI: 10.4025/actascihealthsci.v26i2.1590

    Directory of Open Access Journals (Sweden)

    Graciette Matioli

    2004-04-01

    Full Text Available Atualmente, quando todos os caminhos levam à busca da qualidade total, torna-se indispensável conhecer perfeitamente cada fase de um processo produtivo. Neste caso, a validação é a ferramenta adequada para garantir a confiabilidade de instalação de um processo produtivo, de equipamento e, inclusive, da metodologia analítica. Dessa forma, o presente trabalho teve por objetivo analisar os principais aspectos da validação de métodos analíticos na quantificação do captopril. Foi realizada a validação e a comparação dos seguintes métodos: titulométrico por óxido-redução, espectrofotométrico por Folin-Ciocalteau e cromatográfico por cromatografia líquida de alta eficiência - CLAE. Os atributos de exatidão, precisão, linearidade, especificidade e robustez foram estudados para cada metodologia. Os resultados obtidos demonstraram que o método cromatográfico foi o mais adequado para as análises dos comprimidos de Captopril 25 mg, enquanto que os métodos espectrofotométrico e titulométrico demonstraram valores que satisfazem os critérios de aceitação, porém, com maior variabilidade e menor sensibilidade.Nowadays, when all approaches lead to the search for total quality, a thorough knowledge of every stage of a production process is vital. Validation is an appropriate tool to guarantee the reliabilities of: productive process installation, equipment and also analytical methodology. The aim of the present study was to analyze the main aspects of analytical methods validation for quantifying captopril. Validation and comparison of the following methods were carried out: titrimetric for oxide-reduction, spectrophotometry for Folin-Ciocalteau and high-efficiency liquid chromatography - HPLC. The attributes of accuracy, precision, linearity, specificity and robustness were studied for each methodology. The results show that the chromatographic method was the most suitable for Captopril 25 mg tablets evaluation, while the

  13. RETROSPECTIVE METHOD VALIDATION AND UNCERTAINTY ESTIMATION FOR ACTINIDES DETERMINATION IN EXCRETA BY ALPHA SPECTROMETRY.

    Science.gov (United States)

    Hernández, C; Sierra, I

    2016-09-01

    Two essential technical requirements of ISO 17025 guide for accreditation of testing and calibration laboratories are the validation of methods and the estimation of all sources of uncertainty that may affect the analytical result. Bioelimination Laboratory from Radiation Dosimetry Service of CIEMAT (Spain) uses alpha spectrometry to quantify alpha emitters (Pu, Am, Th, U and Cm isotopes) in urine and faecal samples from workers exposed to internal radiation. Therefore and as a step previous to achieving the ISO 17025 accreditation, the laboratory has performed retrospective studies based on the obtained results in the past few years to validate the analytical method. Uncertainty estimation was done identifying and quantifying all the contributions, and finally the overall combined standard uncertainty was calculated. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Development and validation of stability indicating UPLC assay method for ziprasidone active pharma ingredient

    Directory of Open Access Journals (Sweden)

    Sonam Mittal

    2012-01-01

    Full Text Available Background: Ziprasidone, a novel antipsychotic, exhibits a potent highly selective antagonistic activity on D2 and 5HT2A receptors. Literature survey for ziprasidone revealed several analytical methods based on different techniques but no UPLC method has been reported so far. Aim: Aim of this research paper is to present a simple and rapid stability indicating isocratic, ultra performance liquid chromatographic (UPLC method which was developed and validated for the determination of ziprasidone active pharmaceutical ingredient. Forced degradation studies of ziprasidone were studied under acid, base, oxidative hydrolysis, thermal stress and photo stress conditions. Materials and Methods: The quantitative determination of ziprasidone drug was performed on a Supelco analytical column (100×2.1 mm i.d., 2.7 ΅m with 10 mM ammonium acetate buffer (pH: 6.7 and acetonitrile (ACN as mobile phase with the ratio (55:45-Buffer:ACN at a flow rate of 0.35 ml/ min. For UPLC method, UV detection was made at 318 nm and the run time was 3 min. Developed UPLC method was validated as per ICH guidelines. Results and Conclusion: Mild degradation of the drug substance was observed during oxidative hydrolysis and considerable degradation observed during basic hydrolysis. During method validation, parameters such as precision, linearity, ruggedness, stability, robustness, and specificity were evaluated, which remained within acceptable limits. Developed UPLC method was successfully applied for evaluating assay of Ziprasidone active Pharma ingredient.

  15. Validação em métodos cromatográficos e eletroforéticos Validation for chromatographic and electrophoretic methods

    Directory of Open Access Journals (Sweden)

    Marcelo Ribani

    2004-10-01

    Full Text Available The validation of an analytical method is fundamental to implementing a quality control system in any analytical laboratory. As the separation techniques, GC, HPLC and CE, are often the principal tools used in such determinations, procedure validation is a necessity. The objective of this review is to describe the main aspects of validation in chromatographic and electrophoretic analysis, showing, in a general way, the similarities and differences between the guidelines established by the different Brazilian and international regulatory agencies.

  16. A novel approach to evaluate soil heat flux calculation: An analytical review of nine methods

    Science.gov (United States)

    Gao, Zhongming; Russell, Eric S.; Missik, Justine E. C.; Huang, Maoyi; Chen, Xingyuan; Strickland, Chris E.; Clayton, Ray; Arntzen, Evan; Ma, Yulong; Liu, Heping

    2017-07-01

    There are no direct methods to evaluate calculated soil heat flux (SHF) at the surface (G0). Instead, validation and cross evaluation of methods for calculating G0 usually rely on the conventional calorimetric method or the degree of the surface energy balance closure. However, there is uncertainty in the calorimetric method itself, and factors apart from G0 also contribute to nonclosure of the surface energy balance. Here we used a novel approach to evaluate nine different methods for calculating SHF, including the calorimetric method and methods based on analytical solutions of the heat diffusion equation. The SHF (Gz) measured by a self-calibrating SHF plate at a depth of z = 5 cm below the surface (hereafter Gm_5cm) was deployed as a reference. Each SHF calculation method was assessed by comparing the calculated Gz at the same depth (hereafter Gc_5cm) with Gm_5cm. The calorimetric method and simple measurement method performed best in determining Gc_5cm but still underestimated Gm_5cm by 19% during the daytime. Possible causes for this underestimation include errors and uncertainties in SHF measurements and soil thermal properties, as well as the phase lag between Gc_5cm and Gm_5cm. Our results indicate that the calorimetric method achieves the most accurate SHF estimates if self-calibrating SHF plates are deployed at two depths (e.g., 5 cm and 10 cm), soil temperature and water content measurements are made in a few depths between the two plates, and soil thermal properties are accurately quantified.

  17. Validation of qualitative microbiological test methods

    NARCIS (Netherlands)

    IJzerman-Boon, Pieta C.; van den Heuvel, Edwin R.

    2015-01-01

    This paper considers a statistical model for the detection mechanism of qualitative microbiological test methods with a parameter for the detection proportion (the probability to detect a single organism) and a parameter for the false positive rate. It is demonstrated that the detection proportion

  18. Optimization of the hydrofoil cascade and validation with quasi-analytical solution for hydraulic machinery

    Energy Technology Data Exchange (ETDEWEB)

    Frunza, T; Susan-Resiga, R [Department of Hydraulic Machinery, ' Politehnica' University of Timisoara Bv. Mihai Viteazu 1, RO-300222, Timisoara (Romania); Muntean, S; Bernad, S, E-mail: tfrunza@yahoo.co [Centre of Advanced Research in Engineering Sciences, Romanian Academy - Timisoara Branch, Bv. Mihai Viteazu 24, RO-300223, Timisoara (Romania)

    2010-08-15

    The paper presents the authors ongoing efforts to develop a robust and efficient numerical methodology, and the associated expert software, for analysis, design and optimization of hydrofoil cascades. We developed, so far, a Finite Element solver with streamfunction formulation for incompressible, inviscid and irrotational cascade flow, using a modern software infrastructure, and efficient implementation. Two test cases will be presented to evaluate the accuracy of our CASCADExpert code. In the first case, our code is tested for a thin hydrofoil cascade designed with the quasi-analytical approach. Second, the blade loading and thickness distributions obtain with our code from a given hydrofoil shape are used in an inverse design method. As a result, an optimized hydrofoil cascade is obtained. The pressure distribution on the original and optimized hydrofoil cascades is compared. We have applied the method in order to optimize the turbine and pump hydrofoil cascades, respectively. Consequently, a new method is developed in order to generate the optimized hydrofoil cascade geometry for hydraulic machinery.

  19. Comparative assessment of bioanalytical method validation guidelines for pharmaceutical industry.

    Science.gov (United States)

    Kadian, Naveen; Raju, Kanumuri Siva Rama; Rashid, Mamunur; Malik, Mohd Yaseen; Taneja, Isha; Wahajuddin, Muhammad

    2016-07-15

    The concepts, importance, and application of bioanalytical method validation have been discussed for a long time and validation of bioanalytical methods is widely accepted as pivotal before they are taken into routine use. United States Food and Drug Administration (USFDA) guidelines issued in 2001 have been referred for every guideline released ever since; may it be European Medical Agency (EMA) Europe, National Health Surveillance Agency (ANVISA) Brazil, Ministry of Health and Labour Welfare (MHLW) Japan or any other guideline in reference to bioanalytical method validation. After 12 years, USFDA released its new draft guideline for comments in 2013, which covers the latest parameters or topics encountered in bioanalytical method validation and approached towards the harmonization of bioanalytical method validation across the globe. Even though the regulatory agencies have general agreement, significant variations exist in acceptance criteria and methodology. The present review highlights the variations, similarities and comparison between bioanalytical method validation guidelines issued by major regulatory authorities worldwide. Additionally, other evaluation parameters such as matrix effect, incurred sample reanalysis including other stability aspects have been discussed to provide an ease of access for designing a bioanalytical method and its validation complying with the majority of drug authority guidelines. Copyright © 2016. Published by Elsevier B.V.

  20. Validation of Land Cover Products Using Reliability Evaluation Methods

    OpenAIRE

    Shi, Wenzhong; Zhang, Xiaokang; Hao, Ming; Shao, Pan; Cai, Liping; Lyu, Xuzhe

    2015-01-01

    Validation of land cover products is a fundamental task prior to data applications. Current validation schemes and methods are, however, suited only for assessing classification accuracy and disregard the reliability of land cover products. The reliability evaluation of land cover products should be undertaken to provide reliable land cover information. In addition, the lack of high-quality reference data often constrains validation and affects the reliability results of land cover products. ...

  1. An analytical method for well-formed workflow/Petri net verification of classical soundness

    Directory of Open Access Journals (Sweden)

    Clempner Julio

    2014-12-01

    Full Text Available In this paper we consider workflow nets as dynamical systems governed by ordinary difference equations described by a particular class of Petri nets. Workflow nets are a formal model of business processes. Well-formed business processes correspond to sound workflow nets. Even if it seems necessary to require the soundness of workflow nets, there exist business processes with conditional behavior that will not necessarily satisfy the soundness property. In this sense, we propose an analytical method for showing that a workflow net satisfies the classical soundness property using a Petri net. To present our statement, we use Lyapunov stability theory to tackle the classical soundness verification problem for a class of dynamical systems described by Petri nets. This class of Petri nets allows a dynamical model representation that can be expressed in terms of difference equations. As a result, by applying Lyapunov theory, the classical soundness property for workflow nets is solved proving that the Petri net representation is stable. We show that a finite and non-blocking workflow net satisfies the sound property if and only if its corresponding PN is stable, i.e., given the incidence matrix A of the corresponding PN, there exists a Փ strictly positive m vector such that AՓ≤ 0. The key contribution of the paper is the analytical method itself that satisfies part of the definition of the classical soundness requirements. The method is designed for practical applications, guarantees that anomalies can be detected without domain knowledge, and can be easily implemented into existing commercial systems that do not support the verification of workflows. The validity of the proposed method is successfully demonstrated by application examples.

  2. Analytical methods for the evaluation of melamine contamination.

    Science.gov (United States)

    Cantor, Stuart L; Gupta, Abhay; Khan, Mansoor A

    2014-02-01

    There is an urgent need for the analysis of melamine in the global pharmaceutical supply chain to detect economically motivated adulteration or unintentional contamination using a simple, nondestructive analytical technique that confirms the extent of adulteration in a shorter time period. In this work, different analytical techniques (thermal analysis, X-ray diffraction, Fourier transform infrared (FT-IR), FT-Raman, and near-infrared (NIR) spectroscopy) were evaluated for their ability to detect a range of melamine levels in gelatin. While FT-IR and FT-Raman provided qualitative assessment of melamine contamination or adulteration, powder X-ray diffraction and NIR were able to detect and quantify the presence of melamine at levels as low as 1.0% w/w. Multivariate analysis of the NIR data yielded the most accurate model when three principal components were used. Data were pretreated using standard normal variate transformation to remove multiplicative interferences of scatter and particle size. The model had a root-mean-square error of calibration of 2.4 (R(2) = 0.99) and root-mean square error of prediction of 2.5 (R(2) = 0.96). The value of the paired t test for actual and predicted samples (1%-50% w/w) was 0.448 (p 5), further indicating the robustness of the model. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  3. Are factor analytical techniques used appropriately in the validation of health status questionnaires?

    DEFF Research Database (Denmark)

    de Vet, Henrica C W; Adér, Herman J; Terwee, Caroline B

    2005-01-01

    Factor analysis is widely used to evaluate whether questionnaire items can be grouped into clusters representing different dimensions of the construct under study. This review focuses on the appropriate use of factor analysis. The Medical Outcomes Study Short Form-36 (SF-36) is used as an example...... of methods is crucial for correct interpretation of the results and verification of the conclusions. Our list of criteria may be useful for journal editors, reviewers and researchers who have to assess publications in which factor analysis is applied....... performed. Substantial shortcomings were found in the reporting and justification of the methods applied. In 15 of the 23 studies in which exploratory factor analysis was performed, confirmatory factor analysis would have been more appropriate. Cross-validation was rarely performed. Presentation...

  4. Analytical Method (M) - Metabolonote | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data List Contact us Metabol...lsdba.nbdc01324-003 Description of data contents Information about methods of instrumental analysis. Data file File name: metabol...onote_analytical_method.zip File URL: ftp://ftp.biosciencedbc.jp/archive/metabolonote/LATEST/metabol...://togodb.biosciencedbc.jp/togodb/view/metabolonote_analytical_method#en Data acquisition method - Data anal...his Database Site Policy | Contact Us Analytical Method (M) - Metabolonote | LSDB Archive ...

  5. Examination of fast reactor fuels, FBR analytical quality assurance standards and methods, and analytical methods development: irradiation tests. Progress report, April 1--June 30, 1976, and FY 1976

    International Nuclear Information System (INIS)

    Baker, R.D.

    1976-08-01

    Characterization of unirradiated and irradiated LMFBR fuels by analytical chemistry methods will continue, and additional methods will be modified and mechanized for hot cell application. Macro- and microexaminations will be made on fuel and cladding using the shielded electron microprobe, emission spectrograph, radiochemistry, gamma scanner, mass spectrometers, and other analytical facilities. New capabilities will be developed in gamma scanning, analyses to assess spatial distributions of fuel and fission products, mass spectrometric measurements of burnup and fission gas constituents and other chemical analyses. Microstructural analyses of unirradiated and irradiated materials will continue using optical and electron microscopy and autoradiographic and x-ray techniques. Analytical quality assurance standards tasks are designed to assure the quality of the chemical characterizations necessary to evaluate reactor components relative to specifications. Tasks include: (1) the preparation and distribution of calibration materials and quality control samples for use in quality assurance surveillance programs, (2) the development of and the guidance in the use of quality assurance programs for sampling and analysis, (3) the development of improved methods of analysis, and (4) the preparation of continuously updated analytical method manuals. Reliable analytical methods development for the measurement of burnup, oxygen-to-metal (O/M) ratio, and various gases in irradiated fuels is described

  6. Fuzzy-logic based strategy for validation of multiplex methods: example with qualitative GMO assays.

    Science.gov (United States)

    Bellocchi, Gianni; Bertholet, Vincent; Hamels, Sandrine; Moens, W; Remacle, José; Van den Eede, Guy

    2010-02-01

    This paper illustrates the advantages that a fuzzy-based aggregation method could bring into the validation of a multiplex method for GMO detection (DualChip GMO kit, Eppendorf). Guidelines for validation of chemical, bio-chemical, pharmaceutical and genetic methods have been developed and ad hoc validation statistics are available and routinely used, for in-house and inter-laboratory testing, and decision-making. Fuzzy logic allows summarising the information obtained by independent validation statistics into one synthetic indicator of overall method performance. The microarray technology, introduced for simultaneous identification of multiple GMOs, poses specific validation issues (patterns of performance for a variety of GMOs at different concentrations). A fuzzy-based indicator for overall evaluation is illustrated in this paper, and applied to validation data for different genetically modified elements. Remarks were drawn on the analytical results. The fuzzy-logic based rules were shown to be applicable to improve interpretation of results and facilitate overall evaluation of the multiplex method.

  7. Validation of three rapid screening methods for detection of verotoxin-producing Escherichia coli in foods : interlaboratory study

    NARCIS (Netherlands)

    Capps, K.L.; McLaughlin, E.M.; Murray, A.W.A.; Aldus, C.F.; Wyatt, G.M.; Peck, M.W.; Amerongen, van A.; Ariens, R.M.C.; Wichers, J.H.; Bayliss, C.L.; Wareing, D.R.A.; Bolton, F.J.

    2004-01-01

    An interlaboratory study was conducted for the validation of 3 methods for the detection of all verotoxin-producing Escherichia coli (VTEC) in foods. The methods were a multi-analyte 1-step lateral flow immunoassay (LFIA) for detection of E. coli O157 and verotoxin (VT); an enzyme-linked

  8. A manual of analytical methods used at MINTEK

    International Nuclear Information System (INIS)

    Stoch, H.; Dixon, K.

    1983-01-01

    The manual deals with various methods for a wide range of elemental analysis. Some of the methods that are used, include atomic absorption spectroscopy, optical emission spectroscopy and x-ray fluoresence spectroscopy. The basic charateristics of the method are given and the procedures are recorded step by step. One of the sections deals with methods associated with the recovery of uranium

  9. Analytical Validation of AmpliChip p53 Research Test for Archival Human Ovarian FFPE Sections.

    Directory of Open Access Journals (Sweden)

    Matthew J Marton

    Full Text Available The p53 tumor suppressor gene (TP53 is reported to be mutated in nearly half of all tumors and plays a central role in genome integrity. Detection of mutations in p53 can be accomplished by many assays, including the AmpliChip p53 Research Test. The AmpliChip p53 Research Test has been successfully used to determine p53 status in hematologic malignancies and fresh frozen solid tissues but there are few reports of using the assay with formalin fixed, paraffin-embedded (FFPE tissue. The objective of this study was to describe analytical performance characterization of the AmpliChip p53 Research Test to detect p53 mutations in genomic DNA isolated from archival FFPE human ovarian tumor tissues. Method correlation with sequencing showed 96% mutation-wise agreement and 99% chip-wise agreement. We furthermore observed 100% agreement (113/113 of the most prevalent TP53 mutations. Workflow reproducibility was 96.8% across 8 samples, with 2 operators, 2 reagent lots and 2 instruments. Section-to-section reproducibility was 100% for each sample across a 60 μm region of the FFPE block from ovarian tumors. These data indicate that the AmpliChip p53 Research Test is an accurate and reproducible method for detecting mutations in TP53 from archival FFPE human ovarian specimens.

  10. An analytical method based on multipole moment expansion to calculate the flux distribution in Gammacell-220

    Science.gov (United States)

    Rezaeian, P.; Ataenia, V.; Shafiei, S.

    2017-12-01

    In this paper, the flux of photons inside the irradiation cell of the Gammacell-220 is calculated using an analytical method based on multipole moment expansion. The flux of the photons inside the irradiation cell is introduced as the function of monopole, dipoles and quadruples in the Cartesian coordinate system. For the source distribution of the Gammacell-220, the values of the multipole moments are specified by direct integrating. To confirm the validation of the presented methods, the flux distribution inside the irradiation cell was determined utilizing MCNP simulations as well as experimental measurements. To measure the flux inside the irradiation cell, Amber dosimeters were employed. The calculated values of the flux were in agreement with the values obtained by simulations and measurements, especially in the central zones of the irradiation cell. In order to show that the present method is a good approximation to determine the flux in the irradiation cell, the values of the multipole moments were obtained by fitting the simulation and experimental data using Levenberg-Marquardt algorithm. The present method leads to reasonable results for the all source distribution even without any symmetry which makes it a powerful tool for the source load planning.

  11. Intercalibration of analytical methods on marine environmental samples

    International Nuclear Information System (INIS)

    1985-10-01

    The analytical results reported by the 55 laboratories from 29 countries participating in this intercomparison have enabled to certify the concentration of 16 elements (As, Br, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Na, Rb, Se, Sr, Zn) in the mussel homogenate MA-M-2/TM. Information values could be established for 6 additional elements (Ag, Au, Cl, Pb, Sb, Sc). The atomic absorption spectroscopy was predominantly used in this intercomparison (45% of all determinations). It was followed by neutron activation analysis (28%), atomic emission spectroscopy (15%) and X-ray fluorescence (5%). The total number of outliers was moderate: 11.7% of all results. The number of outlying results by participating laboratories varied between 0 and 6

  12. A simple analytic method for estimating T2 in the knee from DESS.

    Science.gov (United States)

    Sveinsson, B; Chaudhari, A S; Gold, G E; Hargreaves, B A

    2017-05-01

    To introduce a simple analytical formula for estimating T 2 from a single Double-Echo in Steady-State (DESS) scan. Extended Phase Graph (EPG) modeling was used to develop a straightforward linear approximation of the relationship between the two DESS signals, enabling accurate T 2 estimation from one DESS scan. Simulations were performed to demonstrate cancellation of different echo pathways to validate this simple model. The resulting analytic formula was compared to previous methods for T 2 estimation using DESS and fast spin-echo scans in agar phantoms and knee cartilage in three volunteers and three patients. The DESS approach allows 3D (256×256×44) T 2 -mapping with fat suppression in scan times of 3-4min. The simulations demonstrated that the model approximates the true signal very well. If the T 1 is within 20% of the assumed T 1 , the T 2 estimation error was shown to be less than 5% for typical scans. The inherent residual error in the model was demonstrated to be small both due to signal decay and opposing signal contributions. The estimated T 2 from the linear relationship agrees well with reference scans, both for the phantoms and in vivo. The method resulted in less underestimation of T 2 than previous single-scan approaches, with processing times 60 times faster than using a numerical fit. A simplified relationship between the two DESS signals allows for rapid 3D T 2 quantification with DESS that is accurate, yet also simple. The simplicity of the method allows for immediate T 2 estimation in cartilage during the MRI examination. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Development and Validation of a Learning Analytics Framework: Two Case Studies Using Support Vector Machines

    Science.gov (United States)

    Ifenthaler, Dirk; Widanapathirana, Chathuranga

    2014-01-01

    Interest in collecting and mining large sets of educational data on student background and performance to conduct research on learning and instruction has developed as an area generally referred to as learning analytics. Higher education leaders are recognizing the value of learning analytics for improving not only learning and teaching but also…

  14. Investigation by perturbative and analytical method of electronic properties of square quantum well under electric field

    Directory of Open Access Journals (Sweden)

    Mustafa Kemal BAHAR

    2010-06-01

    Full Text Available In this study, the effects of applied electric field on the isolated square quantum well was investigated by analytic and perturbative method. The energy eigen values and wave functions in quantum well were found by perturbative method. Later, the electric field effects were investigated by analytic method, the results of perturbative and analytic method were compared. As well as both of results fit with each other, it was observed that externally applied electric field changed importantly electronic properties of the system.

  15. Analytical validation of a standardized scoring protocol for Ki67: phase 3 of an international multicenter collaboration

    Science.gov (United States)

    Leung, Samuel C Y; Nielsen, Torsten O; Zabaglo, Lila; Arun, Indu; Badve, Sunil S; Bane, Anita L; Bartlett, John M S; Borgquist, Signe; Chang, Martin C; Dodson, Andrew; Enos, Rebecca A; Fineberg, Susan; Focke, Cornelia M; Gao, Dongxia; Gown, Allen M; Grabau, Dorthe; Gutierrez, Carolina; Hugh, Judith C; Kos, Zuzana; Lænkholm, Anne-Vibeke; Lin, Ming-Gang; Mastropasqua, Mauro G; Moriya, Takuya; Nofech-Mozes, Sharon; Osborne, C Kent; Penault-Llorca, Frédérique M; Piper, Tammy; Sakatani, Takashi; Salgado, Roberto; Starczynski, Jane; Viale, Giuseppe; Hayes, Daniel F; McShane, Lisa M; Dowsett, Mitch

    2016-01-01

    Pathological analysis of the nuclear proliferation biomarker Ki67 has multiple potential roles in breast and other cancers. However, clinical utility of the immunohistochemical (IHC) assay for Ki67 immunohistochemistry has been hampered by unacceptable between-laboratory analytical variability. The International Ki67 Working Group has conducted a series of studies aiming to decrease this variability and improve the evaluation of Ki67. This study tries to assess whether acceptable performance can be achieved on prestained core-cut biopsies using a standardized scoring method. Sections from 30 primary ER+ breast cancer core biopsies were centrally stained for Ki67 and circulated among 22 laboratories in 11 countries. Each laboratory scored Ki67 using three methods: (1) global (4 fields of 100 cells each); (2) weighted global (same as global but weighted by estimated percentages of total area); and (3) hot-spot (single field of 500 cells). The intraclass correlation coefficient (ICC), a measure of interlaboratory agreement, for the unweighted global method (0.87; 95% credible interval (CI): 0.81–0.93) met the prespecified success criterion for scoring reproducibility, whereas that for the weighted global (0.87; 95% CI: 0.7999–0.93) and hot-spot methods (0.84; 95% CI: 0.77–0.92) marginally failed to do so. The unweighted global assessment of Ki67 IHC analysis on core biopsies met the prespecified criterion of success for scoring reproducibility. A few cases still showed large scoring discrepancies. Establishment of external quality assessment schemes is likely to improve the agreement between laboratories further. Additional evaluations are needed to assess staining variability and clinical validity in appropriate cohorts of samples. PMID:28721378

  16. VALIDATION OF CYCLAMATE ANALYSIS METHOD WITH SPECTROPHOTOMETRY AND TURBIDIMETRY

    OpenAIRE

    Regina Tutik Padmaningrum; Siti Marwati

    2016-01-01

    This research aims to validate methods of analysis by spectrophotometry and turbidimetry cyclamate in the sample drink mango-flavored jelly drink  by spectrophotometry with hypochlorite reagent, ultraviolet spectrophotometry (without reagent) and turbidimetry. The object of research was the validity parameters spectrophotometric method were linearity, linear range, the limit of detection, limit of quantitation, precision, and accuracy. The calibration curve of standard solution of sodium cycl...

  17. Analytical validation of a melanoma diagnostic gene signature using formalin-fixed paraffin-embedded melanocytic lesions.

    Science.gov (United States)

    Warf, M Bryan; Flake, Darl D; Adams, Doug; Gutin, Alexander; Kolquist, Kathryn A; Wenstrup, Richard J; Roa, Benjamin B

    2015-01-01

    These studies were to validate the analytical performance of a gene expression signature that differentiates melanoma and nevi, using RNA expression from 14 signature genes and nine normalization genes that generates a melanoma diagnostic score (MDS). Formalin-fixed paraffin-embedded melanocytic lesions were evaluated in these studies. The overall SD of the assay was determined to be 0.69 MDS units. Individual amplicons within the signature had an average amplification efficiency of 92% and a SD less than 0.5 CT. The MDS was reproducible across a 2000-fold dilution range of input RNA. Melanin, an inhibitor of PCR, does not interfere with the signature. These studies indicate this signature is robust and reproducible and is analytically validated on formalin-fixed paraffin-embedded melanocytic lesions.

  18. Description of JNC's analytical method and its performance for FBR cores

    International Nuclear Information System (INIS)

    Ishikawa, M.

    2000-01-01

    The description of JNC's analytical method and its performance for FBR cores includes: an outline of JNC's Analytical System Compared with ERANOS; a standard data base for FBR Nuclear Design in JNC; JUPITER Critical Experiment; details of Analytical Method and Its Effects on JUPITER; performance of JNC Analytical System (effective multiplication factor k eff , control rod worth, and sodium void reactivity); design accuracy of a 600 MWe-class FBR Core. JNC developed a consistent analytical system for FBR core evaluation, based on JENDL library, f-table method, and three dimensional diffusion/transport theory, which includes comprehensive sensitivity tools to improve the prediction accuracy of core parameters. JNC system was verified by analysis of JUPITER critical experiment, and other facilities. Its performance can be judged quite satisfactory for FBR-core design work, though there is room for further improvement, such as more detailed treatment of cross-section resonance regions

  19. Development and Validation of a Bioanalytical Method for Direct ...

    African Journals Online (AJOL)

    Erah

    2011-01-16

    Jan 16, 2011 ... Purpose: To develop and validate a user-friendly spiked plasma method for the extraction of diclofenac potassium that reduces the ... Keywords: Bioanalytical method, Diclofenac potassium, RP-HPLC method, NSAIDs, Plasma. Received: 16 ..... R. Enantiospecific Pharmacokinetic Studies on. Ketoprofen in ...

  20. Application of an analytical method for solution of thermal hydraulic conservation equations

    Energy Technology Data Exchange (ETDEWEB)

    Fakory, M.R. [Simulation, Systems & Services Technologies Company (S3 Technologies), Columbia, MD (United States)

    1995-09-01

    An analytical method has been developed and applied for solution of two-phase flow conservation equations. The test results for application of the model for simulation of BWR transients are presented and compared with the results obtained from application of the explicit method for integration of conservation equations. The test results show that with application of the analytical method for integration of conservation equations, the Courant limitation associated with explicit Euler method of integration was eliminated. The results obtained from application of the analytical method (with large time steps) agreed well with the results obtained from application of explicit method of integration (with time steps smaller than the size imposed by Courant limitation). The results demonstrate that application of the analytical approach significantly improves the numerical stability and computational efficiency.

  1. Determination of vitamin C in foods: current state of method validation.

    Science.gov (United States)

    Spínola, Vítor; Llorent-Martínez, Eulogio J; Castilho, Paula C

    2014-11-21

    Vitamin C is one of the most important vitamins, so reliable information about its content in foodstuffs is a concern to both consumers and quality control agencies. However, the heterogeneity of food matrixes and the potential degradation of this vitamin during its analysis create enormous challenges. This review addresses the development and validation of high-performance liquid chromatography methods for vitamin C analysis in food commodities, during the period 2000-2014. The main characteristics of vitamin C are mentioned, along with the strategies adopted by most authors during sample preparation (freezing and acidification) to avoid vitamin oxidation. After that, the advantages and handicaps of different analytical methods are discussed. Finally, the main aspects concerning method validation for vitamin C analysis are critically discussed. Parameters such as selectivity, linearity, limit of quantification, and accuracy were studied by most authors. Recovery experiments during accuracy evaluation were in general satisfactory, with usual values between 81 and 109%. However, few methods considered vitamin C stability during the analytical process, and the study of the precision was not always clear or complete. Potential future improvements regarding proper method validation are indicated to conclude this review. Copyright © 2014. Published by Elsevier B.V.

  2. Downstream processing and chromatography based analytical methods for production of vaccines, gene therapy vectors, and bacteriophages

    Science.gov (United States)

    Kramberger, Petra; Urbas, Lidija; Štrancar, Aleš

    2015-01-01

    Downstream processing of nanoplexes (viruses, virus-like particles, bacteriophages) is characterized by complexity of the starting material, number of purification methods to choose from, regulations that are setting the frame for the final product and analytical methods for upstream and downstream monitoring. This review gives an overview on the nanoplex downstream challenges and chromatography based analytical methods for efficient monitoring of the nanoplex production. PMID:25751122

  3. An Analytical Method for Measuring Competence in Project Management

    Science.gov (United States)

    González-Marcos, Ana; Alba-Elías, Fernando; Ordieres-Meré, Joaquín

    2016-01-01

    The goal of this paper is to present a competence assessment method in project management that is based on participants' performance and value creation. It seeks to close an existing gap in competence assessment in higher education. The proposed method relies on information and communication technology (ICT) tools and combines Project Management…

  4. Analytical Method Details (MS) - Metabolonote | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data List Contact us Metabol...l Analysis information). Data file File name: metabolonote_analytical_method_details.zip File URL: ftp://ftp....biosciencedbc.jp/archive/metabolonote/LATEST/metabolonote_analytical_method_details.zip File size: 73 KB Si...mple search URL http://togodb.biosciencedbc.jp/togodb/view/metabolonote_analytica...cription Download License Update History of This Database Site Policy | Contact Us Analytical Method Details (MS) - Metabolonote | LSDB Archive ...

  5. Experimental evaluation of underride analysis techniques and empirical validation of a new analytical technique.

    Science.gov (United States)

    Boggess, Brian M; Morr, Douglas R; Peterman, Elaine K; Wiechel, John F

    2010-01-01

    Accident reconstructionists are often faced with damage patterns and locations on vehicles that are not well defined by available barrier impact data. One such example is a frontal underride collision. Underride impacts occur when there is a height mismatch between the primary structural components of the impacting vehicles, and the vehicle with the lower height is forced beneath the structure of the other vehicle. The lack of structural engagement typically allows for significantly different damage patterns due to the inherently lower stiffness of the underriding vehicle's contacting surfaces coupled with complex interactions between varying surfaces. In this study, a series of two-vehicle impact tests between a small pickup (bullet vehicle) and a large dump truck (target vehicle) were performed and studied. These tests involved a severe underride configuration in which the dump truck bed's vertical alignment was above the base of the windshield of the pickup. Coupled with these impacting surfaces was a single vertical support, a remnant of a commonly referred to ICC (Interstate Commerce Commission) bumper, which caused a narrow object-type impact, but did not extend down to the pickup's bumper. Multiple prior authors' analytical and empirical relationships to predict impact speed based on crush damage were evaluated using the results of these tests as well as other published underride tests. No single model was sufficient at predicting the mixed mode of impact present in these impact scenarios. However, a system of equations was developed to predict the impact parameters utilizing a combination of previously reported methods and a new empirical relationship presented in this study. This new method shows high correlation and supports the authors' hypothesis that separate crush models can be applied to multiple discrete areas of a vehicle and then combined to form a more complete predictive systematic model.

  6. Reliability and validity of optoelectronic method for biophotonical measurements

    Science.gov (United States)

    Karpienko, Katarzyna; Wróbel, Maciej S.; UrniaŻ, Rafał

    2013-11-01

    Reliability and validity of measurements is of utmost importance when assessing measuring capability of instruments developed for research. In order to perform an experiment which is legitimate, used instruments must be both reliable and valid. Reliability estimates the degree of precision of measurement, the extent to which a measurement is internally consistent. Validity is the usefulness of an instrument to perform accurate measurements of quantities it was designed to measure. Statistical analysis for reliability and validity control of low-coherence interferometry method for refractive index measurements of biological fluids is presented. The low-coherence interferometer is sensitive to optical path difference between interfering beams. This difference depends on the refractive index of measured material. To assess the validity and reliability of proposed method for blood measurements, the statistical analysis of the method was performed on several substances with known refractive indices. Analysis of low-coherence interferograms considered the mean distances between fringes. Performed statistical analysis for validity and reliability consisted of Grubb's test for outliers, Shapiro-Wilk test for normal distribution, T-Student test, standard deviation, coefficient of determination and r-Pearson correlation. Overall the tests proved high statistical significance of measurement method with confidence level measurement method.

  7. Analytical method for the evaluation of the outdoor air contamination by emerging pollutants using tree leaves as bioindicators.

    Science.gov (United States)

    Barroso, Pedro José; Martín, Julia; Santos, Juan Luis; Aparicio, Irene; Alonso, Esteban

    2018-01-01

    In this work, an analytical method, based on sonication-assisted extraction, clean-up by dispersive solid-phase extraction and determination by liquid chromatography-tandem mass spectrometry, has been developed and validated for the simultaneous determination of 15 emerging pollutants in leaves from four ornamental tree species. Target compounds include perfluorinated organic compounds, plasticizers, surfactants, brominated flame retardant, and preservatives. The method was optimized using Box-Behnken statistical experimental design with response surface methodology and validated in terms of recovery, accuracy, precision, and method detection and quantification limits. Quantification of target compounds was carried out using matrix-matched calibration curves. The highest recoveries were achieved for the perfluorinated organic compounds (mean values up to 87%) and preservatives (up to 88%). The lowest recoveries were achieved for plasticizers (51%) and brominated flame retardant (63%). Method detection and quantification limits were in the ranges 0.01-0.09 ng/g dry matter (dm) and 0.02-0.30 ng/g dm, respectively, for most of the target compounds. The method was successfully applied to the determination of the target compounds on leaves from four tree species used as urban ornamental trees (Citrus aurantium, Celtis australis, Platanus hispanica, and Jacaranda mimosifolia). Graphical abstract Analytical method for the biomonitorization of emerging pollutants in outdoor air.

  8. International Harmonization and Cooperation in the Validation of Alternative Methods.

    Science.gov (United States)

    Barroso, João; Ahn, Il Young; Caldeira, Cristiane; Carmichael, Paul L; Casey, Warren; Coecke, Sandra; Curren, Rodger; Desprez, Bertrand; Eskes, Chantra; Griesinger, Claudius; Guo, Jiabin; Hill, Erin; Roi, Annett Janusch; Kojima, Hajime; Li, Jin; Lim, Chae Hyung; Moura, Wlamir; Nishikawa, Akiyoshi; Park, HyeKyung; Peng, Shuangqing; Presgrave, Octavio; Singer, Tim; Sohn, Soo Jung; Westmoreland, Carl; Whelan, Maurice; Yang, Xingfen; Yang, Ying; Zuang, Valérie

    The development and validation of scientific alternatives to animal testing is important not only from an ethical perspective (implementation of 3Rs), but also to improve safety assessment decision making with the use of mechanistic information of higher relevance to humans. To be effective in these efforts, it is however imperative that validation centres, industry, regulatory bodies, academia and other interested parties ensure a strong international cooperation, cross-sector collaboration and intense communication in the design, execution, and peer review of validation studies. Such an approach is critical to achieve harmonized and more transparent approaches to method validation, peer-review and recommendation, which will ultimately expedite the international acceptance of valid alternative methods or strategies by regulatory authorities and their implementation and use by stakeholders. It also allows achieving greater efficiency and effectiveness by avoiding duplication of effort and leveraging limited resources. In view of achieving these goals, the International Cooperation on Alternative Test Methods (ICATM) was established in 2009 by validation centres from Europe, USA, Canada and Japan. ICATM was later joined by Korea in 2011 and currently also counts with Brazil and China as observers. This chapter describes the existing differences across world regions and major efforts carried out for achieving consistent international cooperation and harmonization in the validation and adoption of alternative approaches to animal testing.

  9. Manual of analytical methods for the Industrial Hygiene Chemistry Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Greulich, K.A.; Gray, C.E. (comp.)

    1991-08-01

    This Manual is compiled from techniques used in the Industrial Hygiene Chemistry Laboratory of Sandia National Laboratories in Albuquerque, New Mexico. The procedures are similar to those used in other laboratories devoted to industrial hygiene practices. Some of the methods are standard; some, modified to suit our needs; and still others, developed at Sandia. The authors have attempted to present all methods in a simple and concise manner but in sufficient detail to make them readily usable. It is not to be inferred that these methods are universal for any type of sample, but they have been found very reliable for the types of samples mentioned.

  10. Analytic method for calculating properties of random walks on networks

    Science.gov (United States)

    Goldhirsch, I.; Gefen, Y.

    1986-01-01

    A method for calculating the properties of discrete random walks on networks is presented. The method divides complex networks into simpler units whose contribution to the mean first-passage time is calculated. The simplified network is then further iterated. The method is demonstrated by calculating mean first-passage times on a segment, a segment with a single dangling bond, a segment with many dangling bonds, and a looplike structure. The results are analyzed and related to the applicability of the Einstein relation between conductance and diffusion.

  11. Manual of analytical methods for the Industrial Hygiene Chemistry Laboratory

    International Nuclear Information System (INIS)

    Greulich, K.A.; Gray, C.E.

    1991-08-01

    This Manual is compiled from techniques used in the Industrial Hygiene Chemistry Laboratory of Sandia National Laboratories in Albuquerque, New Mexico. The procedures are similar to those used in other laboratories devoted to industrial hygiene practices. Some of the methods are standard; some, modified to suit our needs; and still others, developed at Sandia. The authors have attempted to present all methods in a simple and concise manner but in sufficient detail to make them readily usable. It is not to be inferred that these methods are universal for any type of sample, but they have been found very reliable for the types of samples mentioned

  12. Practical procedure for method validation in INAA- A tutorial

    International Nuclear Information System (INIS)

    Petroni, Robson; Moreira, Edson G.

    2015-01-01

    This paper describes the procedure employed by the Neutron Activation Laboratory at the Nuclear and Energy Research Institute (LAN, IPEN - CNEN/SP) for validation of Instrumental Neutron Activation Analysis (INAA) methods. According to recommendations of ISO/IEC 17025 the method performance characteristics (limit of detection, limit of quantification, trueness, repeatability, intermediate precision, reproducibility, selectivity, linearity and uncertainties budget) were outline in an easy, fast and convenient way. The paper presents step by step how to calculate the required method performance characteristics in a process of method validation, what are the procedures, adopted strategies and acceptance criteria for the results, that is, how to make a method validation in INAA. In order to exemplify the methodology applied, obtained results for the method validation of mass fraction determination of Co, Cr, Fe, Rb, Se and Zn in biological matrix samples, using an internal reference material of mussel tissue were presented. It was concluded that the methodology applied for validation of INAA methods is suitable, meeting all the requirements of ISO/IEC 17025, and thereby, generating satisfactory results for the studies carried at LAN, IPEN - CNEN/SP. (author)

  13. Practical procedure for method validation in INAA- A tutorial

    Energy Technology Data Exchange (ETDEWEB)

    Petroni, Robson; Moreira, Edson G., E-mail: robsonpetroni@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    This paper describes the procedure employed by the Neutron Activation Laboratory at the Nuclear and Energy Research Institute (LAN, IPEN - CNEN/SP) for validation of Instrumental Neutron Activation Analysis (INAA) methods. According to recommendations of ISO/IEC 17025 the method performance characteristics (limit of detection, limit of quantification, trueness, repeatability, intermediate precision, reproducibility, selectivity, linearity and uncertainties budget) were outline in an easy, fast and convenient way. The paper presents step by step how to calculate the required method performance characteristics in a process of method validation, what are the procedures, adopted strategies and acceptance criteria for the results, that is, how to make a method validation in INAA. In order to exemplify the methodology applied, obtained results for the method validation of mass fraction determination of Co, Cr, Fe, Rb, Se and Zn in biological matrix samples, using an internal reference material of mussel tissue were presented. It was concluded that the methodology applied for validation of INAA methods is suitable, meeting all the requirements of ISO/IEC 17025, and thereby, generating satisfactory results for the studies carried at LAN, IPEN - CNEN/SP. (author)

  14. Potential of accuracy profile for method validation in inductively coupled plasma spectrochemistry

    International Nuclear Information System (INIS)

    Mermet, J.M.; Granier, G.

    2012-01-01

    Method validation is usually performed over a range of concentrations for which analytical criteria must be verified. One important criterion in quantitative analysis is accuracy, i.e. the contribution of both trueness and precision. The study of accuracy over this range is called an accuracy profile and provides experimental tolerance intervals. Comparison with acceptability limits fixed by the end user defines a validity domain. This work describes the computation involved in the building of the tolerance intervals, particularly for the intermediate precision with within-laboratory experiments and for the reproducibility with interlaboratory studies. Computation is based on ISO 5725‐4 and on previously published work. Moreover, the bias uncertainty is also computed to verify the bias contribution to accuracy. The various types of accuracy profile behavior are exemplified with results obtained by using ICP-MS and ICP-AES. This procedure allows the analyst to define unambiguously a validity domain for a given accuracy. However, because the experiments are time-consuming, the accuracy profile method is mainly dedicated to method validation. - Highlights: ► An analytical method is defined by its accuracy, i.e. both trueness and precision. ► The accuracy as a function of an analyte concentration is an accuracy profile. ► Profile basic concepts are explained for trueness and intermediate precision. ► Profile-based tolerance intervals have to be compared with acceptability limits. ► Typical accuracy profiles are given for both ICP-AES and ICP-MS techniques.

  15. Development and validation of a HILIC- MS/MS multi-targeted method for metabolomics applications.

    Science.gov (United States)

    Virgiliou, Christina; Sampsonidis, Ioannis; Gika, Helen G; Raikos, Nikolaos; Theodoridis, Georgios A

    2015-07-14

    The paper reports the development of a multi-analyte method and its application in metabolic profiling of biological fluids. The initial aim of the method was the quantification of metabolites existing in cell culture medium used in in-vitro fertilisation (IVF) and in other biological fluids related to embryo growth. Since most of these analytes are polar primary metabolites a hydrophilic interaction liquid chromatography (HILIC) system was selected. The analytical system comprised Ultra (High) performance liquid chromatography (UHPLC) with detection on a triple quadrupole mass spectrometer operating in both positive and negative modes. Mobile phase and gradient elution conditions were studied with the aim to achieve the highest coverage of metabolic space in a single injection namely the largest number of analytes that could be detected and quantified. The developed method provides absolute quantitation of ca. 100 metabolites belonging to key metabolite classes such as sugars, aminoacids, nucleotides, organic acids and amines. Following validation, the method was applied for the metabolic profiling of hundreds of samples of spent culture medium originating from human IVF procedures and several hundreds of biological samples such as amniotic fluid, human urine and blood serum from pregnant women. The bioanalytical end-point was to provide assistance in the process of embryo transfer and improving IVF success rates but also to provide insight in complications related to the subsequent embryo growth during pregnancy. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  16. Analytical Evaluation of Beam Deformation Problem Using Approximate Methods

    DEFF Research Database (Denmark)

    Barari, Amin; Kimiaeifar, A.; Domairry, G.

    2010-01-01

    The beam deformation equation has very wide applications in structural engineering. As a differential equation, it has its own problem concerning existence, uniqueness and methods of solutions. Often, original forms of governing differential equations used in engineering problems are simplified...

  17. EVALUATION OF ANALYTICAL METHODS FOR DETERMINING PESTICIDES IN BABY FOOD

    Science.gov (United States)

    Three extraction methods and two detection techniques for determining pesticides in baby food were evaluated. The extraction techniques examined were supercritical fluid extraction (SFE), enhanced solvent extraction (ESE), and solid phase extraction (SPE). The detection techni...

  18. Analytical validation of the Roche 25-OH Vitamin D Total assay

    DEFF Research Database (Denmark)

    Knudsen, Cindy Soendersoe; Nexo, Ebba; Højskov, Carsten Schriver

    2012-01-01

    Background: Vitamin D deficiency is considered a major health issue and therefore there is a need for reliable routine tests for measurement of the vitamin in blood samples. Here we present a validation of the recently released Roche 25-OH Vitamin D Total assay (Vitamin D Total). Methods: We...... evaluated the 25-OH Vitamin D Total assay in comparison to our in-house liquid chromatography tandem mass spectrometry (LC-MS/MS) method [194 patient samples without 25-hydroxy vitamin D2 (25OHD2) and 23 patient samples containing 25OHD2]. Results: At concentrations of 34 and 56 nmol/L within-run CVs were 4......) showed Vitamin D Total nmol/L=1.07×(LC-MS/MS) nmol/L+4.7 nmol/L, whereas comparison of 25OHD2 using 23 patient samples showed Vitamin D Total nmol/L=0.55×(LC-MS/MS) nmol/L–2.38 nmol/L (Demings regression). Conclusions: The Roche Vitamin D Total assay is judged suitable for measurement of 25OHD in serum...

  19. A fast analytical method for the addition of random variables

    International Nuclear Information System (INIS)

    Senna, V.; Milidiu, R.L.; Fleming, P.V.; Salles, M.R.; Oliveira, L.F.S. de

    1982-01-01

    Using the minimal cut sets representation of a fault tree, a new approach to the method of moments is proposed in order to estimate confidence bounds to the top event probability. The method utilizes two or three moments either to fit a distribution (the normal and lognormal families) or to evaluate bounds from standard inequalities (e.g. Markov, Tchebycheff, etc.). Examples indicate that the results obtained by the lognormal family are in good agreement with those obtained by Monte Carlo simulation. (Author) [pt

  20. Cluster Analytical Method of Fault Risk Analysis in Systems

    Science.gov (United States)

    Michaľčonok, German; Horalová Kalinová, Michaela

    2016-12-01

    In providing safety functions, the proposal of safety functions of control systems is an important part of a risk reduction strategy. In the specification of security requirements, it is necessary to determine and document individual characteristics and the desired performance level for each safety. This article presents the results of the experiment cluster analysis. The results of the experiment prove that the methods of cluster analysis provide a suitable tool for analyzing the reliability of safety systems analysis. Regarding the increasing complexity of the systems, we can state that the application of these methods in the subject area is a good choice.

  1. Fast analytical method for the addition of random variables

    International Nuclear Information System (INIS)

    Senna, V.; Milidiu, R.L.; Fleming, P.V.; Salles, M.R.; Oliveria, L.F.S.

    1983-01-01

    Using the minimal cut sets representation of a fault tree, a new approach to the method of moments is proposed in order to estimate confidence bounds to the top event probability. The method utilizes two or three moments either to fit a distribution (the normal and lognormal families) or to evaluate bounds from standard inequalities (e.g. Markov, Tchebycheff, etc.) Examples indicate that the results obtained by the log-normal family are in good agreement with those obtained by Monte Carlo simulation

  2. New Analytical Method for the Determination of Metronidazole in ...

    African Journals Online (AJOL)

    Methods: Metronidazole was extracted from human plasma through one step of protein precipitation by methanol using carbamazepine as internal standard (IS). After centrifugation of the plasma sample, the supernatant layer was separated and injected into HPLC system using Eclipse XDB-phenyl column. The mobile ...

  3. An Analytical framework of social learning facilitated by participatory methods

    NARCIS (Netherlands)

    Scholz, G.; Dewulf, A.; Pahl-Wostl, C.

    2014-01-01

    Social learning among different stakeholders is often a goal in problem solving contexts such as environmental management. Participatory methods (e.g., group model-building and role playing games) are frequently assumed to stimulate social learning. Yet understanding if and why this assumption is

  4. Analytic comparison of time- and frequency-domain electromagnetic methods

    Energy Technology Data Exchange (ETDEWEB)

    Stoyer, C.H.

    1980-01-01

    The time- and frequency-domain methods of electromagnetic geophysical prospecting are compared to determine the similarities and differences and to recommend system choices for particular field situations. Only the wire-loop configuration is considered, as this array is quite standard in geothermal prospecting. Comparisons are carried out using hardware and physical considerations, a large catalog of 3-layer model curves, 2D-3D model calculations, and by comparing Fourier transforms and layered inversions of field data from the Randsburg KGRA in California. The results generally indicate that frequency-domain methods offer better resolution and more practical hardware design for long-offset shallow applications. They also have a much better backup in terms of modelling tools for interpretation and history of experience. Transient methods are better suited for deeper probing, for both long- and short-offset applications. Frequency-domain methods are limited by the primary field, which is subject to distortion from near-surface inhomogeneites; this is also the case for early-time transients. Transient measurements in late time are limited by ambient electromagnetic noise and dynamic range of receiving equipment.

  5. Analytic Method for Pressure Recovery in Truncated Diffusers ...

    African Journals Online (AJOL)

    A prediction method is presented for the static pressure recovery in subsonic axisymmetric truncated conical diffusers. In the analysis, a turbulent boundary layer is assumed at the diffuser inlet and a potential core exists throughout the flow. When flow separation occurs, this approach cannot be used to predict the maximum ...

  6. Pressurised liquid extraction of flavonoids in onions. Method development and validation

    DEFF Research Database (Denmark)

    Søltoft, Malene; Christensen, J.H.; Nielsen, J.

    2009-01-01

    A rapid and reliable analytical method for quantification of flavonoids in onions was developed and validated. Five extraction methods were tested on freeze-dried onions and subsequently high performance liquid chromatography (HPLC) with UV detection was used for quantification of seven flavonoids...... extraction methods. However. PLE was the preferred extraction method because the method can be highly automated, use only small amounts of solvents, provide the cleanest extracts, and allow the extraction of light and oxygen-sensitive flavonoids to be carried out in an inert atmosphere protected from light......-step PLE method showed good selectivity, precision (RSDs = 3.1-11%) and recovery of the extractable flavonoids (98-99%). The method also appeared to be a multi-method, i.e. generally applicable to, e.g. phenolic acids in potatoes and carrots....

  7. Approximate Analytic Solutions for the Two-Phase Stefan Problem Using the Adomian Decomposition Method

    Directory of Open Access Journals (Sweden)

    Xiao-Ying Qin

    2014-01-01

    Full Text Available An Adomian decomposition method (ADM is applied to solve a two-phase Stefan problem that describes the pure metal solidification process. In contrast to traditional analytical methods, ADM avoids complex mathematical derivations and does not require coordinate transformation for elimination of the unknown moving boundary. Based on polynomial approximations for some known and unknown boundary functions, approximate analytic solutions for the model with undetermined coefficients are obtained using ADM. Substitution of these expressions into other equations and boundary conditions of the model generates some function identities with the undetermined coefficients. By determining these coefficients, approximate analytic solutions for the model are obtained. A concrete example of the solution shows that this method can easily be implemented in MATLAB and has a fast convergence rate. This is an efficient method for finding approximate analytic solutions for the Stefan and the inverse Stefan problems.

  8. The criterion-related validity of personality measures for predicting GPA: a meta-analytic validity competition.

    Science.gov (United States)

    McAbee, Samuel T; Oswald, Frederick L

    2013-06-01

    Interest in the role of personality traits in predicting academic performance outcomes has steadily increased over the last several decades, enough to produce a number of meta-analyses that summarize this research (e.g., Poropat, 2009; Richardson, Abraham, & Bond, 2012). These previous meta-analyses combine a variety of alternative personality measures under the assumption that they all reflect the same personality traits and thus predict outcomes similarly. The current meta-analysis tests this assumption by comparing different personality measures when predicting postsecondary grade point average (GPA). The operational validities (r+) of 5 frequently used measures of the Big Five personality traits were compared: the NEO Personality Inventory--Revised (NEO-PI-R; Costa & McCrae, 1992), the NEO Five-Factor Inventory (NEO-FFI; Costa & McCrae, 1992), the Big Five Inventory (BFI; e.g., Benet-Martínez & John, 1998), Goldberg's (1992) unipolar Big Five Factor Markers (Markers), and the Big Five International Personality Item Pool (IPIP; Goldberg, 1999). A systematic review of the psychological literature from 1992 to 2012 was conducted, identifying 51 studies containing 274 correlations. Conscientiousness demonstrated the strongest criterion-related validity for predicting GPA (r+ = .23), consistent with previous meta-analyses; in addition, this overall validity was found to be robust across measures (r(BFI)(+) = .24, r(IPIP)(+) = .21, r(Markers)(+) = .15, r(NEO-FFI)(+) = .24, r(NEO-PI-R)(+) = .26). Although the criterion-related validities for Extraversion, Agreeableness, Neuroticism, and Openness to Experience (Intellect) differed by measure, they were generally low (r+s < .10). Practical implications of the findings and directions for future research are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  9. Development and Validation of a Bioanalytical Method for Direct ...

    African Journals Online (AJOL)

    Purpose: To develop and validate a user-friendly spiked plasma method for the extraction of diclofenac potassium that reduces the number of treatments with plasma sample, in order to minimize human error. Method: Instead of solvent evaporation technique, the spiked plasma sample was modified with H2SO4 and NaCl, ...

  10. Development and Validation of Improved Method for Fingerprint ...

    African Journals Online (AJOL)

    Purpose: To develop and validate an improved method by capillary zone electrophoresis with photodiode array detection for the fingerprint analysis of Ligusticum chuanxiong Hort. (Rhizoma Chuanxiong). Methods: The optimum high performance capillary electrophoresis (HPCE) conditions were 30 mM borax containing 5 ...

  11. Validated method for the detection and quantitation of synthetic ...

    African Journals Online (AJOL)

    Validated method for the detection and quantitation of synthetic cannabinoids in whole blood and urine, and its application to postmortem cases in Johannesburg, South ... A LC-HRMS (liquid chromatography coupled with high resolution mass spectrometry) method for the detection and quantitation of several synthetic ...

  12. Predictive validity of the Hand Arm Risk assessment Method (HARM)

    NARCIS (Netherlands)

    Douwes, M.; Boocock, M.; Coenen, P.; Heuvel, S. van den; Bosch, T.

    2014-01-01

    The Hand Arm Risk assessment Method (HARM) is a simplified risk assessment method for determining musculoskeletal symptoms to the arm, neck and/or shoulder posed by hand-arm tasks of the upper body. The purpose of this study was to evaluate the predictive validity of HARM using data collected from a

  13. [Progress in sample preparation and analytical methods for trace polar small molecules in complex samples].

    Science.gov (United States)

    Zhang, Qianchun; Luo, Xialin; Li, Gongke; Xiao, Xiaohua

    2015-09-01

    Small polar molecules such as nucleosides, amines, amino acids are important analytes in biological, food, environmental, and other fields. It is necessary to develop efficient sample preparation and sensitive analytical methods for rapid analysis of these polar small molecules in complex matrices. Some typical materials in sample preparation, including silica, polymer, carbon, boric acid and so on, are introduced in this paper. Meanwhile, the applications and developments of analytical methods of polar small molecules, such as reversed-phase liquid chromatography, hydrophilic interaction chromatography, etc., are also reviewed.

  14. Validation of a method to determine methylmercury in fish tissues using gas chromatography

    International Nuclear Information System (INIS)

    Vega Bolannos, Luisa O.; Arias Verdes, Jose A.; Beltran Llerandi, Gilberto; Castro Diaz, Odalys; Moreno Tellez, Olga L.

    2000-01-01

    We validated a method to determine methylmercury in fish tissues using gas chromatography with an electron capture detector as described by the Association of Official Analytical Chemist (AOAC) International. The linear curve range was 0.02 to 1 g/ml and linear correlation coefficient was 0.9979. A 1 mg/kg methylmercury-contaminated fish sample was analyzed 20 times to determine repeatability of the method. The quantification limit was 0.16 mg/kg and detection limit was 0.06 ppm. Fish samples contaminated with 0.2 to 10 mg/kg methylmercury showed recovery indexes from 94.66 to 108.8%

  15. Numerical Validation of the Delaunay Normalization and the Krylov-Bogoliubov-Mitropolsky Method

    Directory of Open Access Journals (Sweden)

    David Ortigosa

    2014-01-01

    Full Text Available A scalable second-order analytical orbit propagator programme based on modern and classical perturbation methods is being developed. As a first step in the validation and verification of part of our orbit propagator programme, we only consider the perturbation produced by zonal harmonic coefficients in the Earth’s gravity potential, so that it is possible to analyze the behaviour of the mathematical expressions involved in Delaunay normalization and the Krylov-Bogoliubov-Mitropolsky method in depth and determine their limits.

  16. A new robust method for the treatment of analytical data

    International Nuclear Information System (INIS)

    Pearton, D.C.G.

    1982-01-01

    A new robust method is proposed for the calculation of the median and the relative standard deviation for a set of data containing unsymmetrically placed outliers. Examples of the advantages of the new method are given, the findings being confirmed by Monte Carlo tests. At Mintek mass-spectrometric data are often unsymmetrical, and all outliers are often at one of the extremities, either all high or all low. In some instances the outliers can be seen visually, and would therefore be rejected on sight. However, when large sets of results are processed, such as those from mass-spectrometric, X-ray fluorescence, and neutron-activation analyses, or in fields such as the assignment of values to reference materials, the sets of results are often too large for visual inspection and are processed within the computer

  17. [Molecular epidemiology of infectious diseases: analytical methods and results interpretation].

    Science.gov (United States)

    Sammarco, M L; Ripabelli, G; Tamburro, M

    2014-01-01

    Molecular typing and fingerprinting of microbial pathogens represent an essential tool for the epidemiological surveillance, outbreak detection and control of infectious diseases. Indeed, epidemiological investigation without genotyping data may not provide comprehensive information to allow the most appropriate interventions; despite this consideration, some barriers still hamper the routine application and interpretation of molecular typing data. In this paper, the most important methods currently used for characterization of pathogenic microorganisms for microbial source tracking and for the identification of clonal relationships among different isolates, are described according to their principles, advantages and limitations. Criteria for their evaluation and guidelines for the correct interpretation of results are also proposed. Molecular typing methods can be grouped into four categories based on different methodological principles, which include the characterization of restriction sites in genomic or plasmid DNA; the amplification of specific genetic targets; the restriction enzyme digestion and the subsequent amplification; sequence analysis. Although the development and the extensive use of molecular typing systems have greatly improved the understanding of the infectious diseases epidemiology, the rapid diversification, partial evaluation and lack of comparative data on the methods have raised significant questions about the selection of the most appropriate typing method, as well as difficulties for the lack of consensus about the interpretation of the results and nomenclature used for interpretation. Several criteria should be considered in order to evaluate the intrinsic performance and practical advantages of a typing system. However none of the available genotyping methods fully meets all these requirements. Therefore, the combined use of different approaches may lead to a more precise characterization and discrimination of isolates than a single

  18. Validación de un método de análisis para la determinación de hidrocarburos aromáticos policíclicos por cromatografía líquida de alta eficiencia en partículas PM10 Y PM2,5 Validation of an analytical method for the determination of polycyclic aromatic hydrocarbons by high efficiency liquid chromatography in PM10 and PM2, 5

    Directory of Open Access Journals (Sweden)

    Jorge Herrera Murillo

    2012-11-01

    Full Text Available Se validó un método analítico para la determinación de hidrocarburos aromáticos policíclicos presentes en partículas PM10 y PM 2,5 recolectadas en el aire mediante cromatografía líquida de alta resolución (CLAR. Los HPA incluidos en la metodología comprenden: Naftaleno, Acenaftileno, Fluoreno, Acenafteno, Fenantreno, Antraceno, Fluoranteno, Pireno, Benzo (aantraceno, Criseno, Benzo (bfluoranteno, Benzo (kfluoranteno, Benzo (apireno, Dibenzo (a,h antraceno, Benzo (g,h,iperileno y Indeno (1,2,3- C.D pireno. Para estos compuestos, los límites de detección y cuantificación estuvieron entre 0,02 y 0,1 mg/l utilizando un equipo marca Dionex modelo ICS- 3000, el cual consta de dos detectores en serie, un ultravioleta modelo VWD-1 y un detector de fluorescencia modelo RF-2000, permitiendo diferenciar las distintas señales de absorción y emisión para la debida identificación de los distintos compuestos. Para todos los compuestos analizados, el factor de recuperación resultó no ser significativamente diferente de uno y la repetibilidad y reproducibilidad resultó ser adecuada para un método analítico, especialmente para los HPA más ligeros.An analytical method for polycyclic aromatic hydrocarbons in PM10 and PM 2.5 par ticles collected from air by high performance liquid chromatography (HPLC was validated. The PAHs analyzed in the methodology include: Naphthalene, Acenaphthylene, Fluorene, Acenaphthene, Phenanthrene, Anthracene, fluoranthene,pyrene,Benzo(aanthracene,Chrysene, Benzo (bfluoranthene, Benzo (kfluoranthene, Benzo (apyrene Dibenzo (a, hanthracene, Benzo (g, h, iperylene and Indeno (1,2,3-CDpyrene. For these compounds, the detection limit and quantification limit were between 0,02 and 0,1 mg/l using a DIONEX ICS 3000 model cromatograph, that has two in serie detectors: UV/Vis and Fluorescense, separating the different absorption and emission signals for proper identification of individual compounds. For all the compounds

  19. A method of calculating the Jost function for analytic potentials

    International Nuclear Information System (INIS)

    Rakityansky, S.A.; Amos, K.

    1995-01-01

    A combination of the variable-constant and complex coordinate rotation methods is used to solve the two-body Schroedinger equation. The equation is replaced by a system of linear first-order differential equations, which enables one to perform direct calculation of the Jost function for all complex momenta of physical interest including the spectral points corresponding to bound and resonance states. 16 refs., 2 tabs., 2 figs

  20. Diclofenac quantification: analytical attributes of a spectrophotometric method

    OpenAIRE

    Monzón, Celina M.; Delfino, Mario R.; Sarno, María del C.; Delfino, Mario R. (h)

    2011-01-01

    An spectrophotometric UV-visible technique used to quantify diclofenac and its application to pharmaceutical preparations is described, based on diclofenac oxidation by Fe(III) in the presence of ophenanthroline. The formation of tris (o-phenanthroline)-Fe(II) complex (ferroin) upon diclofenac reaction was investigated. Absorbance of ferroin complex was measured at 506 nm. This method was tested on 50 mg tablets. Operating with placebos, it was found that excipients do not interfere with the ...

  1. Analytical methods applied to diverse types of Brazilian propolis

    Directory of Open Access Journals (Sweden)

    Marcucci Maria

    2011-06-01

    Full Text Available Abstract Propolis is a bee product, composed mainly of plant resins and beeswax, therefore its chemical composition varies due to the geographic and plant origins of these resins, as well as the species of bee. Brazil is an important supplier of propolis on the world market and, although green colored propolis from the southeast is the most known and studied, several other types of propolis from Apis mellifera and native stingless bees (also called cerumen can be found. Propolis is usually consumed as an extract, so the type of solvent and extractive procedures employed further affect its composition. Methods used for the extraction; analysis the percentage of resins, wax and insoluble material in crude propolis; determination of phenolic, flavonoid, amino acid and heavy metal contents are reviewed herein. Different chromatographic methods applied to the separation, identification and quantification of Brazilian propolis components and their relative strengths are discussed; as well as direct insertion mass spectrometry fingerprinting. Propolis has been used as a popular remedy for several centuries for a wide array of ailments. Its antimicrobial properties, present in propolis from different origins, have been extensively studied. But, more recently, anti-parasitic, anti-viral/immune stimulating, healing, anti-tumor, anti-inflammatory, antioxidant and analgesic activities of diverse types of Brazilian propolis have been evaluated. The most common methods employed and overviews of their relative results are presented.

  2. A Vocal-Based Analytical Method for Goose Behaviour Recognition

    Directory of Open Access Journals (Sweden)

    Henrik Karstoft

    2012-03-01

    Full Text Available Since human-wildlife conflicts are increasing, the development of cost-effective methods for reducing damage or conflict levels is important in wildlife management. A wide range of devices to detect and deter animals causing conflict are used for this purpose, although their effectiveness is often highly variable, due to habituation to disruptive or disturbing stimuli. Automated recognition of behaviours could form a critical component of a system capable of altering the disruptive stimuli to avoid this. In this paper we present a novel method to automatically recognise goose behaviour based on vocalisations from flocks of free-living barnacle geese (Branta leucopsis. The geese were observed and recorded in a natural environment, using a shielded shotgun microphone. The classification used Support Vector Machines (SVMs, which had been trained with labeled data. Greenwood Function Cepstral Coefficients (GFCC were used as features for the pattern recognition algorithm, as they can be adjusted to the hearing capabilities of different species. Three behaviours are classified based in this approach, and the method achieves a good recognition of foraging behaviour (86–97% sensitivity, 89–98% precision and a reasonable recognition of flushing (79–86%, 66–80% and landing behaviour(73–91%, 79–92%. The Support Vector Machine has proven to be a robust classifier for this kind of classification, as generality and non-linearcapabilities are important. We conclude that vocalisations can be used to automatically detect behaviour of conflict wildlife species, and as such, may be used as an integrated part of awildlife management system.

  3. Plastics in soil: Analytical methods and possible sources.

    Science.gov (United States)

    Bläsing, Melanie; Amelung, Wulf

    2018-01-15

    At least 300 Mio t of plastic are produced annually, from which large parts end up in the environment, where it persists over decades, harms biota and enters the food chain. Yet, almost nothing is known about plastic pollution of soil; hence, the aims of this work are to review current knowledge on i) available methods for the quantification and identification of plastic in soil, ii) the quantity and possible input pathways of plastic into soil, (including first preliminary screening of plastic in compost), and iii) its fate in soil. Methods for plastic analyses in sediments can potentially be adjusted for application to soil; yet, the applicability of these methods for soil needs to be tested. Consequently, the current data base on soil pollution with plastic is still poor. Soils may receive plastic inputs via plastic mulching or the application of plastic containing soil amendments. In compost up to 2.38-1200mg plastic kg -1 have been found so far; the plastic concentration of sewage sludge varies between 1000 and 24,000 plastic items kg -1 . Also irrigation with untreated and treated wastewater (1000-627,000 and 0-125,000 plastic items m -3 , respectively) as well as flooding with lake water (0.82-4.42 plastic items m -3 ) or river water (0-13,751 items km -2 ) can provide major input pathways for plastic into soil. Additional sources comprise littering along roads and trails, illegal waste dumping, road runoff as well as atmospheric input. With these input pathways, plastic concentrations in soil might reach the per mill range of soil organic carbon. Most of plastic (especially >1μm) will presumably be retained in soil, where it persists for decades or longer. Accordingly, further research on the prevalence and fate of such synthetic polymers in soils is urgently warranted. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. An analytical investigation on unsteady motion of vertically falling spherical particles in non-Newtonian fluid by Collocation Method

    Directory of Open Access Journals (Sweden)

    M. Rahimi-Gorji

    2015-06-01

    Full Text Available An analytical investigation is applied for unsteady motion of a rigid spherical particle in a quiescent shear-thinning power-law fluid. The results were compared with those obtained from Collocation Method (CM and the established Numerical Method (Fourth order Runge–Kutta scheme. It was shown that CM gave accurate results. Collocation Method (CM and Numerical Method are used to solve the present problem. We obtained that the CM which was used to solve such nonlinear differential equation with fractional power is simpler and more accurate than series method such as HPM which was used in some previous works by others but the new method named Akbari-Ganji’s Method (AGM is an accurate and simple method which is slower than CM for solving such problems. The terminal settling velocity—that is the velocity at which the net forces on a falling particle eliminate—for three different spherical particles (made of plastic, glass and steel and three flow behavior index n, in three sets of power-law non-Newtonian fluids was investigated, based on polynomial solution (CM. Analytical results obtained indicated that the time of reaching the terminal velocity in a falling procedure is significantly increased with growing of the particle size that validated with Numerical Method. Further, with approaching flow behavior to Newtonian behavior from shear-thinning properties of flow (n → 1, the transient time to achieving the terminal settling velocity is decreased.

  5. Applications of Nuclear Analytical Methods for High Tech Industry

    International Nuclear Information System (INIS)

    Hossain, T.

    2013-01-01

    Silicon based semiconductor chip manufacturing is a worldwide high technology industry with numerous measurement issues. One of the major concerns in the semiconductor manufacturing is contamination such as the trace metal impurities. This concern is vividly illustrated by the fact that the manufacturing in this industry is done in ultra clean environment where the entire manufacturing facility or “Fab” is a clean room facility or each and every manufacturing tool is enclosed in a mini-environment Although semiconductor devices are fabricated on the surface of the Si wafers contamination in the bulk material is a major concern. Nuclear methods of analysis are uniquely suited for the contamination analysis in such a matrix. Many opportunities in the semiconductor manufacturing field exist for the nuclear methods to provide support services. Contamination analysis by NAA, depth profiles by NDP and prompt gamma analysis of H in thin films are a few examples. These needs are on-going and require commitment from the lab so that a manufacturing operation can rely on the delivery of these services when required

  6. Validation of a method for the analysis of biogenic amines: histamine instability during wine sample storage.

    Science.gov (United States)

    Bach, Benoit; Le Quere, Stephanie; Vuchot, Patrick; Grinbaum, Magali; Barnavon, Laurent

    2012-06-30

    This paper reports on the development of an optimized method for the simultaneous analysis of eight biogenic amines (histamine, methylamine, ethylamine, tyramine, putrescine, cadaverine, phenethylamine, and isoamylamine). The analytical method thus proposed has the following advantages: the easy derivatization of wine, the quantification of biogenic amines and a complete degradation of excess derivatization reagent during sample preparation in order to preserve the column. It consists in reversed phase separation by HPLC and UV-vis detection of the aminoenones formed by the reaction of amino compounds with the derivatization reagent diethyl ethoxymethylenemalonate (DEEMM). The usefulness of this technique was confirmed by an alternative oenological analytical method for the validation, quality control and uncertainty assessment (OIV Oeno 10/2005). The method was validated and proposed as a reference method to the International Organization of Vine and Wine (OIV). As a specific application of the proposed method, the biogenic amine content of Rhône valley wines was investigated. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. An analytical method of estimating Value-at-Risk on the Belgrade Stock Exchange

    Directory of Open Access Journals (Sweden)

    Obadović Milica D.

    2009-01-01

    Full Text Available This paper presents market risk evaluation for a portfolio consisting of shares that are continuously traded on the Belgrade Stock Exchange, by applying the Value-at-Risk model - the analytical method. It describes the manner of analytical method application and compares the results obtained by implementing this method at different confidence levels. Method verification was carried out on the basis of the failure rate that demonstrated the confidence level for which this method was acceptable in view of the given conditions.

  8. JRC Guidelines for 1 - Selecting and/or validating analytical methods for cosmetics 2 - Recommending standardization steps of analytical methods

    OpenAIRE

    VINCENT Ursula

    2015-01-01

    The analysis of cosmetics constitutes a challenge mainly due to the large variety of ingredients and formulations, and to the complexity of cosmetic products, in particular due to huge matrix variability. In 2009, the European Commission issued a Regulation (Regulation (EC) N° 1223/2009 of the European Parliament and of the Council) establishing the requisites for cosmetic products and the responsibilities of the stakeholders. While the manufacturers' are responsible to ensure the safety of t...

  9. Colloids in PWR primary and secondary coolant. Innovative analytical methods

    International Nuclear Information System (INIS)

    Nowotka, Karsten; Guillodo, Michael; Burchardt, Carsten; Geier, Roland; Lehr, Robert; Stellwag, Bernhard

    2014-01-01

    Transport and deposition of corrosion products in the colloid size range between 1 nm and 1 μm are important for heat transfer performance and corrosion in primary and secondary cooling circuits of LWRs. Direct analysis of the properties of small-sized colloids (< 0.45 μm) is difficult due to the pronounced change of the physicochemical properties of coolant samples in sampling lines. An innovative method, based on a filter cascade and developed in the AREVA Technical Center, named 'Colloid Catcher' (CC, patent pending), permits on-line measurements of the properties of corrosion products in the coolant of LWRs. CC measurements are complementary to classic trace analysis addressing the soluble content. Low and high temperature (up to 330°C) test sections are available, depending on our customer's needs. The CC contains differential pressure detectors at each of the three consecutive membrane filters which allow for an in-situ characterization without modification of the corrosion products chemical nature due to temperature changes and subsequent exposure to the atmosphere. With this method, a 'Colloid Fingerprint' of the test solution can be obtained, ideal for an assessment of the transport and deposition of corrosion products in laboratory and on-site studies. The on-line data can of course be complemented by post filtration membrane characterization by digestion and/or optical methods. The high temperature CC serves at the same time as a sampling point for grab samples, with good reproducibility thanks to continuous liquid flow. The CC has been designed to be deployable on laboratory or industrial cooling circuits. The CC test sections have been qualified using AREVA Technical Center's test loops. First test results obtained with the LT CC are presented. Laboratory data can be used to back up existing results and data of on-site measurement campaigns at BWR and PWR plants which were determined with a basic version of the LT CC

  10. VALIDATION OF CYCLAMATE ANALYSIS METHOD WITH SPECTROPHOTOMETRY AND TURBIDIMETRY

    Directory of Open Access Journals (Sweden)

    Regina Tutik Padmaningrum

    2016-04-01

    Full Text Available This research aims to validate methods of analysis by spectrophotometry and turbidimetry cyclamate in the sample drink mango-flavored jelly drink  by spectrophotometry with hypochlorite reagent, ultraviolet spectrophotometry (without reagent and turbidimetry. The object of research was the validity parameters spectrophotometric method were linearity, linear range, the limit of detection, limit of quantitation, precision, and accuracy. The calibration curve of standard solution of sodium cyclamate in the spectrophotometric method with hypochlorite reagent, UV spectrophotometry (without reagent, and turbidimetry are linear. Linear range each method respectively at a concentration were (211.36-747.08; (16.000-146.434; and (1.8521-6.1717 ppm. The detection limit of each method successively were 53.6028; 0.5833; and 0.2723 ppm. Limit of quantitation each method successively were 66.9948; 1.9443; and 0.8068 ppm. Spectrophotometric analysis method cyclamate with hypochlorite reagent had good precision and accuracy. Ultra violet  spectrophotometric analysis method of cyclamate have a good precision but the accuracy was not good. Turbidimetric methods  analysis of cyclamate had  precision and accuracy were not good. Keywords:   method validation, spectrophotometry, turbidimetry, cyclamate

  11. Modelling of packet traffic with matrix analytic methods

    DEFF Research Database (Denmark)

    Andersen, Allan T.

    1995-01-01

    vot reveal any adverse behaviour. In fact the observed traffic seemed very close to what would be expected from Poisson traffic. The Changeover/Changeback procedure in SS7, which is used to redirect traffic in case of link failure, has been analyzed. The transient behaviour during a Changeover...... scenario was modelled using Markovian models. The Ordinary Differential Equations arising from these models were solved numerically. The results obtained seemed very similar to those obtained using a different method in previous work by Akinpelu & Skoog 1985. Recent measurement studies of packet traffic...... is found by noting the close relationship with the expressions for the corresponding infinite queue. For the special case of a batch Poisson arrival process this observation makes it possible to express the queue length at an arbitrary in terms of the corresponding queue lengths for the infinite case....

  12. Using an analytical geometry method to improve tiltmeter data presentation

    Science.gov (United States)

    Su, W.-J.

    2000-01-01

    The tiltmeter is a useful tool for geologic and geotechnical applications. To obtain full benefit from the tiltmeter, easy and accurate data presentations should be used. Unfortunately, the most commonly used method for tilt data reduction now may yield inaccurate and low-resolution results. This article describes a simple, accurate, and high-resolution approach developed at the Illinois State Geological Survey for data reduction and presentation. The orientation of tiltplates is determined first by using a trigonometric relationship, followed by a matrix transformation, to obtain the true amount of rotation change of the tiltplate at any given time. The mathematical derivations used for the determination and transformation are then coded into an integrated PC application by adapting the capabilities of commercial spreadsheet, database, and graphics software. Examples of data presentation from tiltmeter applications in studies of landfill covers, characterizations of mine subsidence, and investigations of slope stability are also discussed.

  13. Manual of analytical methods for the Environmental Health Laboratory

    International Nuclear Information System (INIS)

    Gray, C.E.

    1975-06-01

    The manual contains four sections: absorption spectrophotometry; general radiochemical procedures; instrumental analysis; and calibration of field instruments. Included in the individual analyses using absorption spectrophotometry is one for total iodine in oil. Radiochemical procedures are given for: actinides in urine and water; 137 Cs in soil and vegetation; 137 Cs in soil, urine, vegetation, and water; enriched uranium in urine; gross beta activity in soil, urine, vegetation, and water; plutonium in urine and soil; 210 Po in urine and water; 24 Na in air, blood, urine, and water; 90 Sr in soil, vegetation, and water; tritium in urine, water, and on swipes; and total uranium on fallout trays and in soil, urine, and water. Among the individual instrumental analyses is a spectrographic method for determining beryllium in air samples and swipes. (U.S.)

  14. Analytical Chemistry Laboratory (ACL) procedure compendium. Volume 4, Organic methods

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-01

    This interim notice covers the following: extractable organic halides in solids, total organic halides, analysis by gas chromatography/Fourier transform-infrared spectroscopy, hexadecane extracts for volatile organic compounds, GC/MS analysis of VOCs, GC/MS analysis of methanol extracts of cryogenic vapor samples, screening of semivolatile organic extracts, GPC cleanup for semivolatiles, sample preparation for GC/MS for semi-VOCs, analysis for pesticides/PCBs by GC with electron capture detection, sample preparation for pesticides/PCBs in water and soil sediment, report preparation, Florisil column cleanup for pesticide/PCBs, silica gel and acid-base partition cleanup of samples for semi-VOCs, concentrate acid wash cleanup, carbon determination in solids using Coulometrics` CO{sub 2} coulometer, determination of total carbon/total organic carbon/total inorganic carbon in radioactive liquids/soils/sludges by hot persulfate method, analysis of solids for carbonates using Coulometrics` Model 5011 coulometer, and soxhlet extraction.

  15. Validação de método analítico para determinar a migração de ε-caprolactama das embalagens para alimentos gordurosos Validation of analytical method to determine ε-caprolactam migration from packagings to fatty food

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Justo Bomfim

    2010-01-01

    Full Text Available ε-Caprolactam (CAP is a monomer of nylon 6 used as food packaging for bologna sausage, turkey blanquettes, fowl breast, pâtés and ham luncheon meat. After polymerization a part of the monomer can remain in the packaging and migrate into the food. The aim of this work was develop and validate a single laboratory method to determine CAP in ethanol 95% that simulates fatty food characteristics. Thus, linear range was 2 to 32 mg/L of CAP, detection and quantification limits were 0.83 and 1.63 mg/L, respectively. Repeatability showed Hor Rat values lower than 2 while recovery range was 97.5 to 106.5%. The method was considered adequate for purpose.

  16. Amphenicols stability in medicated feed – development and validation of liquid chromatography method

    Directory of Open Access Journals (Sweden)

    Pietro Wojciech Jerzy

    2014-12-01

    Full Text Available A liquid chromatography-ultraviolet detection method for the determination of florfenicol (FF and thiamphenicol (TAP in feeds is presented. The method comprises the extraction of analytes from the matrix with a mixture of methanol and acetonitrile, drying of the extract, and its dissolution in phosphate buffer. The analysis was performed with a gradient programme of the mobile phase composed of acetonitrile and buffer (pH = 7.3 on a Zorbax Eclipse Plus C18 (150 × 4.6 mm, 5 μm analytical column with UV (λ = 220 nm detection. The analytical procedure has been successfully adopted and validated for quantitative determination of florfenicol and thiamphenicol in feed samples. Sensitivity, specificity, linearity, repeatability, and intralaboratory reproducibility were included in the validation. The mean recovery of amphenicols was 93.5% within the working range of 50-4000 mg/kg. Simultaneous determination of chloramphenicol, which is banned in the feed, was also included within the same procedure of FF and TAP stability studies. Storing the medicated feed at room temperature for up to one month decreased concentration in the investigated drugs even by 45%. These findings are relevant to successful provision of therapy to animals.

  17. Arab Scientific Working Group for Forensic Toxicology (ASWGFT: Guidelines for Method Validation in Forensic Toxicology

    Directory of Open Access Journals (Sweden)

    Abdulsallam A. Bakdash

    2018-01-01

    Full Text Available Reliable results and valid analytical data are an essential requirement for proper interpretation of forensic toxicology cases, especially when evaluating scientific studies and daily routine work, and when presenting any toxicological findings as a criminal evidence. In contrast, the results of unreliable analyses can be disputed in court and can also lead to unfair legal judgments against the defendant, or can result in wrong treatment in cases of rehabilitation for patients. In order to establish strong evidence and make a correct decision, the lab is asked to give high quality data that are based on reliable analytical methods. For that reason, all new analytical methods used in forensic toxicology, including the clinical diagnosis of causes of death, require careful care during the development of the analytical method and during its application. This is also an urgent need in the context of quality management and accreditation, especially as those issues have become increasingly important in the science of poisons and drug analysis in recent years. The Arab Society for forensic sciences and forensic medicine (ASFSFM will publish the first version of Guidelines for Method Validation in Forensic Toxicology issued by the Arab Scientific Working Group of Forensic Toxicology (ASWGFT. This aims to be a distinguished scientific publication written in Arabic which introducing the scientific terms of analytical methods in the field of forensic toxicology to Arab readers. The Arab Scientific Working Group of Forensic Toxicology has chosen the first issue to be a manual of guidelines for method validation in forensic toxicology, similar to the international organizations who are actively publishing in this field. The guidelines contain a systematic scientific message that can be published and circulated among Arab laboratories. It will also encourage other Arab scientific working groups in the field of forensic sciences to produce similar publications

  18. The validation and regulatory acceptance of alternative methods in Japan.

    Science.gov (United States)

    Ohno, Yasuo

    2004-06-01

    Except for the genotoxicity test, there are two regulatory guidelines in Japan for in vitro toxicity studies. One of them is a cytotoxicity test for the safety evaluation of extracts from plastic devices for medical use. The other is an in vitro endotoxin test (the Limulus test). These are included in the Japanese Pharmacopoeia. Japan also accepts data obtained from these tests conducted according to OECD guidelines. On the other hand, the Ministry of Health and Welfare (MHW) indicated in 1996 that they would accept alternatives to the Draize eye irritation test for safety evaluation of cosmetics if the method were appropriate. Therefore, the MHW/Japan Cosmetic Industry Association validation group conducted validation studies on alternative methods and indicated that the results of several cytotoxicity tests correlated very well with those of Draize scores obtained from rabbit tests. Based on the results, draft guidelines to evaluate the eye irritation potential of cosmetic ingredients were prepared and submitted to the MHW 1999, in which in vitro methods were incorporated. Validation requires a lot of resources and time. Therefore, we recently constructed an evaluation scheme for alternative methods with the support of the Ministry. This was based on the research, on published manuscripts, and on validation reports. We intended to clarify the performance of the method with its limitations. Without having this information, both regulators and industry persons would make big mistakes in evaluating the results of alternative methods. As a first trial of the project, research on the in vitro phototoxicity test was conducted.

  19. Alternative methods for ocular toxicology testing: validation, applications and troubleshooting.

    Science.gov (United States)

    Dholakiya, Sanjay L; Barile, Frank A

    2013-06-01

    Humanitarian concern, scientific progress and legislative action have lead to the development, validation and regulatory acceptance of alternative in vitro ocular models. However, to date not a single in vitro alternative ocular toxicity test has been validated as a full replacement for the in vivo Draize rabbit eye test for all classes of chemicals across whole irritancy ranges. Since the 1990s, ocular alternative methods have been validated but few have been accepted for regulatory purposes. These assays include: organotypic models, such as the bovine corneal opacity and permeability (BCOP) assay, the isolated chicken eye (ICE) test method and cell function-based in vitro assays, such as the cytosensor microphysiometer (CM) and the fluorescein leakage (FL) test methods. Some refinements to in vivo testing methods have been accepted by regulatory agencies, including humane endpoints to avoid or minimize pain and distress. The authors provide a review of the background, protocol overview, applications and their validation status of the tier-testing approach. Furthermore, the authors provide expert analysis and provide their perspective on this approach and potential future developments. In the search for a battery of methods that replaces the in vivo Draize test, it is necessary to prioritize techniques, define related mechanisms and justify statistical approaches. Overall, only when the reliability and relevance of a method is unequivocally supported will any technique be ready for regulatory acceptance.

  20. Chemical analysis of solid residue from liquid and solid fuel combustion: Method development and validation

    Energy Technology Data Exchange (ETDEWEB)

    Trkmic, M. [University of Zagreb, Faculty of Mechanical Engineering and Naval Architecturek Zagreb (Croatia); Curkovic, L. [University of Zagreb, Faculty of Chemical Engineering and Technology, Zagreb (Croatia); Asperger, D. [HEP-Proizvodnja, Thermal Power Plant Department, Zagreb (Croatia)

    2012-06-15

    This paper deals with the development and validation of methods for identifying the composition of solid residue after liquid and solid fuel combustion in thermal power plant furnaces. The methods were developed for energy dispersive X-ray fluorescence (EDXRF) spectrometer analysis. Due to the fuels used, the different composition and the location of creation of solid residue, it was necessary to develop two methods. The first method is used for identifying solid residue composition after fuel oil combustion (Method 1), while the second method is used for identifying solid residue composition after the combustion of solid fuels, i. e. coal (Method 2). Method calibration was performed on sets of 12 (Method 1) and 6 (Method 2) certified reference materials (CRM). CRMs and analysis test samples were prepared in pellet form using hydraulic press. For the purpose of method validation the linearity, accuracy, precision and specificity were determined, and the measurement uncertainty of methods for each analyte separately was assessed. The methods were applied in the analysis of real furnace residue samples. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Propulsion and launching analysis of variable-mass rockets by analytical methods

    Directory of Open Access Journals (Sweden)

    D.D. Ganji

    2013-09-01

    Full Text Available In this study, applications of some analytical methods on nonlinear equation of the launching of a rocket with variable mass are investigated. Differential transformation method (DTM, homotopy perturbation method (HPM and least square method (LSM were applied and their results are compared with numerical solution. An excellent agreement with analytical methods and numerical ones is observed in the results and this reveals that analytical methods are effective and convenient. Also a parametric study is performed here which includes the effect of exhaust velocity (Ce, burn rate (BR of fuel and diameter of cylindrical rocket (d on the motion of a sample rocket, and contours for showing the sensitivity of these parameters are plotted. The main results indicate that the rocket velocity and altitude are increased with increasing the Ce and BR and decreased with increasing the rocket diameter and drag coefficient.

  2. A SIMPLE ANALYTICAL METHOD TO DETERMINE SOLAR ENERGETIC PARTICLES' MEAN FREE PATH

    International Nuclear Information System (INIS)

    He, H.-Q.; Qin, G.

    2011-01-01

    To obtain the mean free path of solar energetic particles (SEPs) for a solar event, one usually has to fit time profiles of both flux and anisotropy from spacecraft observations to numerical simulations of SEPs' transport processes. This method can be called a simulation method. But a reasonably good fitting needs a lot of simulations, which demand a large amount of calculation resources. Sometimes, it is necessary to find an easy way to obtain the mean free path of SEPs quickly, for example, in space weather practice. Recently, Shalchi et al. provided an approximate analytical formula of SEPs' anisotropy time profile as a function of particles' mean free path for impulsive events. In this paper, we determine SEPs' mean free path by fitting the anisotropy time profiles from Shalchi et al.'s analytical formula to spacecraft observations. This new method can be called an analytical method. In addition, we obtain SEPs' mean free path with the traditional simulation methods. Finally, we compare the mean free path obtained with the simulation method to that of the analytical method to show that the analytical method, with some minor modifications, can give us a good, quick approximation of SEPs' mean free path for impulsive events.

  3. Analytical methods for 2,4-D (Dichlorophenoxyacetic acid) determination

    International Nuclear Information System (INIS)

    Martinez G, M.S.M.

    1999-01-01

    The 2,4-D herbicide is one of the main pesticides for controlling the bad grass in crops such as the water undergrowth. In Mexico the allowed bound of this pesticide is 0.05 mg/l in water of 2,4-D so it is required to have methods trusts and exacts, which can used in order to detected low concentration of it. In this work we show some for the conventional techniques and for establishing the 2,4-D concentrations. The UV-Vis spectrometer and liquids chromatography due that they are the most common used nowadays. Beside, we introduce a now developed technique, which is based on the neutronic activation analysis. Though use of the UV-Vis spectrometer technique it was possible target the concentrations interval between 1 and 200 mg/l. In the liquids chromatography interval was between 0.1 and 0.9, and by the neutronic activation analysis the interval was between 0.01 and 200 mg/l. (Author)

  4. An introduction to clinical microeconomic analysis: purposes and analytic methods.

    Science.gov (United States)

    Weintraub, W S; Mauldin, P D; Becker, E R

    1994-06-01

    The recent concern with health care economics has fostered the development of a new discipline that is generally called clinical microeconomics. This is a discipline in which microeconomic methods are used to study the economics of specific medical therapies. It is possible to perform stand alone cost analyses, but more profound insight into the medical decision making process may be accomplished by combining cost studies with measures of outcome. This is most often accomplished with cost-effectiveness or cost-utility studies. In cost-effectiveness studies there is one measure of outcome, often death. In cost-utility studies there are multiple measures of outcome, which must be grouped together to give an overall picture of outcome or utility. There are theoretical limitations to the determination of utility that must be accepted to perform this type of analysis. A summary statement of outcome is quality adjusted life years (QALYs), which is utility time socially discounted survival. Discounting is used because people value a year of future life less than a year of present life. Costs are made up of in-hospital direct, professional, follow-up direct, and follow-up indirect costs. Direct costs are for medical services. Indirect costs reflect opportunity costs such as lost time at work. Cost estimates are often based on marginal costs, or the cost for one additional procedure of the same type. Finally an overall statistic may be generated as cost per unit increase in effectiveness, such as dollars per QALY.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Waste Tank Organic Safety Program: Analytical methods development. Progress report, FY 1994

    International Nuclear Information System (INIS)

    Campbell, J.A.; Clauss, S.A.; Grant, K.E.

    1994-09-01

    The objectives of this task are to develop and document extraction and analysis methods for organics in waste tanks, and to extend these methods to the analysis of actual core samples to support the Waste Tank organic Safety Program. This report documents progress at Pacific Northwest Laboratory (a) during FY 1994 on methods development, the analysis of waste from Tank 241-C-103 (Tank C-103) and T-111, and the transfer of documented, developed analytical methods to personnel in the Analytical Chemistry Laboratory (ACL) and 222-S laboratory. This report is intended as an annual report, not a completed work

  6. Monitoring of emerging pollutants in Guadiamar River basin (South of Spain): analytical method, spatial distribution and environmental risk assessment.

    Science.gov (United States)

    Garrido, Eva; Camacho-Muñoz, Dolores; Martín, Julia; Santos, Antonio; Santos, Juan Luis; Aparicio, Irene; Alonso, Esteban

    2016-12-01

    Guadiamar River is located in the southwest of the Iberian Peninsula and connects two protected areas in the South of Spain: Sierra Morena and Doñana National Park. It is sited in an area affected by urban, industrial and agriculture sewage pollution and with tradition on intensive mining activities. Most of the studies performed in this area have been mainly focused on the presence of heavy metals and, until now, little is known about the occurrence of other contaminants such as emerging organic pollutants (EOPs). In this work, an analytical method has been optimized and validated for monitoring of forty-seven EOPs in surface water. The analytical method has been applied to study the distribution and environmental risk of these pollutants in Guadiamar River basin. The analytical method was based on solid-phase extraction and determination by liquid chromatography-triple quadrupole-tandem mass spectrometry. The 60 % of the target compounds were found in the analyzed samples. The highest concentrations were found for two plasticizers (bisphenol A and di(2-ethyhexyl)phthalate, mean concentration up to 930 ng/L) and two pharmaceutical compounds (caffeine (up to 623 ng/L) and salicylic acid (up to 318 ng/L)). This study allowed to evaluate the potential sources (industrial or urban) of the studied compounds and the spatial distribution of their concentrations along the river. Environmental risk assessment showed a major risk on the south of the river, mainly due to discharges of wastewater effluents.

  7. Application of capability indices and control charts in the analytical method control strategy.

    Science.gov (United States)

    Oliva, Alexis; Llabres Martinez, Matías

    2017-08-01

    In this study, we assessed the usefulness of control charts in combination with the process capability indices, C pm and C pk , in the control strategy of an analytical method. The traditional X-chart and moving range chart were used to monitor the analytical method over a 2-year period. The results confirmed that the analytical method is in-control and stable. Different criteria were used to establish the specifications limits (i.e. analyst requirements) for fixed method performance (i.e. method requirements). If the specification limits and control limits are equal in breadth, the method can be considered "capable" (C pm  = 1), but it does not satisfy the minimum method capability requirements proposed by Pearn and Shu (2003). Similar results were obtained using the C pk index. The method capability was also assessed as a function of method performance for fixed analyst requirements. The results indicate that the method does not meet the requirements of the analytical target approach. A real-example data of a SEC with light-scattering detection method was used as a model whereas previously published data were used to illustrate the applicability of the proposed approach. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Analytical chemistry in semiconductor manufacturing: Techniques, role of nuclear methods and need for quality control

    International Nuclear Information System (INIS)

    1989-06-01

    This report is the result of a consultants meeting held in Gaithersburg, USA, 2-3 October 1987. The meeting was hosted by the National Bureau of Standards and Technology, and it was attended by 18 participants from Denmark, Finland, India, Japan, Norway, People's Republic of China and the USA. The purpose of the meeting was to assess the present status of analytical chemistry in semiconductor manufacturing, the role of nuclear analytical methods and the need for internationally organized quality control of the chemical analysis. The report contains the three presentations in full and a summary report of the discussions. Thus, it gives an overview of the need of analytical chemistry in manufacturing of silicon based devices, the use of nuclear analytical methods, and discusses the need for quality control. Refs, figs and tabs

  9. Ernst Equation and Riemann Surfaces: Analytical and Numerical Methods

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Frederick J [FJE Enterprises, 511 County Route 59, Potsdam, NY 13676 (United States)

    2007-06-18

    source can be represented by discontinuities in the metric tensor components. The first two chapters of this book are devoted to some basic ideas: in the introductory chapter 1 the authors discuss the concept of integrability, comparing the integrability of the vacuum Ernst equation with the integrability of nonlinear equations of Korteweg-de Vries (KdV) type, while in chapter 2 they describe various circumstances in which the vacuum Ernst equation has been determined to be relevant, not only in connection with gravitation but also, for example, in the construction of solutions of the self-dual Yang-Mills equations. It is also in this chapter that one of several equivalent linear systems for the Ernst equation is described. The next two chapters are devoted to Dmitry Korotkin's concept of algebro-geometric solutions of a linear system: in chapter 3 the structure of such solutions of the vacuum Ernst equation, which involve Riemann theta functions of hyperelliptic algebraic curves of any genus, is contrasted with the periodic structure of such solutions of the KdV equation. How such solutions can be obtained, for example, by solving a matrix Riemann-Hilbert problem and how the metric tensor of the associated spacetime can be evaluated is described in detail. In chapter 4 the asymptotic behaviour and the similarity structure of the general algebro-geometric solutions of the Ernst equation are described, and the relationship of such solutions to the perhaps more familiar multi-soliton solutions is discussed. The next three chapters are based upon the authors' own published research: in chapter 5 it is shown that a problem involving counter-rotating infinitely thin disks of matter can be solved in terms of genus two Riemann theta functions, while in chapter 6 the authors describe numerical methods that facilitate the construction of such solutions, and in chapter 7 three-dimensional graphs are displayed that depict all metrical fields of the associated spacetime

  10. Assessing the impact of natural policy experiments on socioeconomic inequalities in health: how to apply commonly used quantitative analytical methods?

    Directory of Open Access Journals (Sweden)

    Yannan Hu

    2017-04-01

    Full Text Available Abstract Background The scientific evidence-base for policies to tackle health inequalities is limited. Natural policy experiments (NPE have drawn increasing attention as a means to evaluating the effects of policies on health. Several analytical methods can be used to evaluate the outcomes of NPEs in terms of average population health, but it is unclear whether they can also be used to assess the outcomes of NPEs in terms of health inequalities. The aim of this study therefore was to assess whether, and to demonstrate how, a number of commonly used analytical methods for the evaluation of NPEs can be applied to quantify the effect of policies on health inequalities. Methods We identified seven quantitative analytical methods for the evaluation of NPEs: regression adjustment, propensity score matching, difference-in-differences analysis, fixed effects analysis, instrumental variable analysis, regression discontinuity and interrupted time-series. We assessed whether these methods can be used to quantify the effect of policies on the magnitude of health inequalities either by conducting a stratified analysis or by including an interaction term, and illustrated both approaches in a fictitious numerical example. Results All seven methods can be used to quantify the equity impact of policies on absolute and relative inequalities in health by conducting an analysis stratified by socioeconomic position, and all but one (propensity score matching can be used to quantify equity impacts by inclusion of an interaction term between socioeconomic position and policy exposure. Conclusion Methods commonly used in economics and econometrics for the evaluation of NPEs can also be applied to assess the equity impact of policies, and our illustrations provide guidance on how to do this appropriately. The low external validity of results from instrumental variable analysis and regression discontinuity makes these methods less desirable for assessing policy effects

  11. Analysis of plasticizers in PVC medical devices: Performance comparison of eight analytical methods.

    Science.gov (United States)

    Bernard, L; Bourdeaux, D; Pereira, B; Azaroual, N; Barthélémy, C; Breysse, C; Chennell, P; Cueff, R; Dine, T; Eljezi, T; Feutry, F; Genay, S; Kambia, N; Lecoeur, M; Masse, M; Odou, P; Radaniel, T; Simon, N; Vaccher, C; Verlhac, C; Yessad, M; Décaudin, B; Sautou, V

    2017-01-01

    A wide variety of medical devices (MDs) used in hospitals are made of flexible plasticized polyvinylchloride (PVC). Different plasticizers are present in variable amounts in the PVC matrix of the devices and can leach out into the infused solutions and may enter into contact with the patients. The ARMED 1 project aims to assess the migration of these plasticizers from medical devices and therefore the level of exposure in patients. For the first task of the project, eight methods were developed to directly detect and quantify the plasticizers in the PVC matrix of the MDs. We compared the overall performances of the analytical methods using standardized and validated criteria in order to provide the scientific community with the guidance and the technical specifications of each method for the intended application. We have shown that routine rapid screening could be performed directly on the MDs using the FTIR technique, with cost-effective analyses. LC techniques may also be used, but with limits and only with individual quantification of the main plasticizers expected in the PVC matrix. GC techniques, especially GC-MS, are both more specific and more sensitive than other techniques. NMR is a robust and specific technique to precisely discriminate all plasticizers in a MD but is limited by its cost and its low ability to detect and quantify plasticizer contamination, e.g. by DEHP. All these results have been confirmed by a real test, called the " blind test " carried out on 10 MD samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Experimental validation of analytical models for a rapid determination of cycle parameters in thermoplastic injection molding

    Science.gov (United States)

    Pignon, Baptiste; Sobotka, Vincent; Boyard, Nicolas; Delaunay, Didier

    2017-10-01

    Two different analytical models were presented to determine cycle parameters of thermoplastics injection process. The aim of these models was to provide quickly a first set of data for mold temperature and cooling time. The first model is specific to amorphous polymers and the second one is dedicated to semi-crystalline polymers taking the crystallization into account. In both cases, the nature of the contact between the polymer and the mold could be considered as perfect or not (thermal contact resistance was considered). Results from models are compared with experimental data obtained with an instrumented mold for an acrylonitrile butadiene styrene (ABS) and a polypropylene (PP). Good agreements were obtained for mold temperature variation and for heat flux. In the case of the PP, the analytical crystallization times were compared with those given by a coupled model between heat transfer and crystallization kinetics.

  13. Evaluation and selection of in-situ leaching mining method using analytic hierarchy process

    International Nuclear Information System (INIS)

    Zhao Heyong; Tan Kaixuan; Liu Huizhen

    2007-01-01

    According to the complicated conditions and main influence factors of in-situ leaching min- ing, a model and processes of analytic hierarchy are established for evaluation and selection of in-situ leaching mining methods based on analytic hierarchy process. Taking a uranium mine in Xinjiang of China for example, the application of this model is presented. The results of analyses and calculation indicate that the acid leaching is the optimum project. (authors)

  14. Application of Statistical Methods to Activation Analytical Results near the Limit of Detection

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Wanscher, B.

    1978-01-01

    Reporting actual numbers instead of upper limits for analytical results at or below the detection limit may produce reliable data when these numbers are subjected to appropriate statistical processing. Particularly in radiometric methods, such as activation analysis, where individual standard...... deviations of analytical results may be estimated, improved discrimination may be based on the Analysis of Precision. Actual experimental results from a study of the concentrations of arsenic in human skin demonstrate the power of this principle....

  15. Parametric validations of analytical lifetime estimates for radiation belt electron diffusion by whistler waves

    Directory of Open Access Journals (Sweden)

    A. V. Artemyev

    2013-04-01

    Full Text Available The lifetimes of electrons trapped in Earth's radiation belts can be calculated from quasi-linear pitch-angle diffusion by whistler-mode waves, provided that their frequency spectrum is broad enough and/or their average amplitude is not too large. Extensive comparisons between improved analytical lifetime estimates and full numerical calculations have been performed in a broad parameter range representative of a large part of the magnetosphere from L ~ 2 to 6. The effects of observed very oblique whistler waves are taken into account in both numerical and analytical calculations. Analytical lifetimes (and pitch-angle diffusion coefficients are found to be in good agreement with full numerical calculations based on CRRES and Cluster hiss and lightning-generated wave measurements inside the plasmasphere and Cluster lower-band chorus waves measurements in the outer belt for electron energies ranging from 100 keV to 5 MeV. Comparisons with lifetimes recently obtained from electron flux measurements on SAMPEX, SCATHA, SAC-C and DEMETER also show reasonable agreement.

  16. An analytical method for solving exact solutions of a nonlinear evolution equation describing the dynamics of ionic currents along microtubules

    Directory of Open Access Journals (Sweden)

    Md. Nur Alam

    2017-11-01

    Full Text Available In this article, a variety of solitary wave solutions are observed for microtubules (MTs. We approach the problem by treating the solutions as nonlinear RLC transmission lines and then find exact solutions of Nonlinear Evolution Equations (NLEEs involving parameters of special interest in nanobiosciences and biophysics. We determine hyperbolic, trigonometric, rational and exponential function solutions and obtain soliton-like pulse solutions for these equations. A comparative study against other methods demonstrates the validity of the technique that we developed and demonstrates that our method provides additional solutions. Finally, using suitable parameter values, we plot 2D and 3D graphics of the exact solutions that we observed using our method. Keywords: Analytical method, Exact solutions, Nonlinear evolution equations (NLEEs of microtubules, Nonlinear RLC transmission lines

  17. An experimental method for validating compressor valve vibration theory

    NARCIS (Netherlands)

    Habing, R.A.; Peters, M.C.A.M.

    2006-01-01

    This paper presents an experimental method for validating traditional compressor valve theory for unsteady flow conditions. Traditional valve theory considers the flow force acting on the plate and the flow rate as quasi-steady variables. These variables are related via semi-empirical coefficients

  18. Validated RP-HPLC Method for Quantification of Phenolic ...

    African Journals Online (AJOL)

    Purpose: To evaluate the total phenolic content and antioxidant potential of the methanol extracts of aerial parts and roots of Thymus sipyleus Boiss and also to determine some phenolic compounds using a newly developed and validated reversed phase high performance liquid chromatography (RP-HPLC) method.

  19. Development and Validation of a Liquid Chromatographic Method ...

    African Journals Online (AJOL)

    A liquid chromatographic method for the simultaneous determination of six human immunodeficiency virus (HIV) protease inhibitors, indinavir, saquinavir, ritonavir, amprenavir, nelfinavir and lopinavir, was developed and validated. Optimal separation was achieved on a PLRP-S 100 Å, 250 x 4.6 mm I.D. column maintained ...

  20. Development and Validation of an HPLC Method for the Analysis of Sirolimus in Drug Products

    Directory of Open Access Journals (Sweden)

    Hadi Valizadeh

    2012-05-01

    Full Text Available Purpose: The aim of this study was to develop a simple, rapid and sensitive reverse phase high performance liquid chromatography (RP-HPLC method for quantification of sirolimus (SRL in pharmaceutical dosage forms. Methods: The chromatographic system employs isocratic elution using a Knauer- C18, 5 mm, 4.6 × 150 mm. Mobile phase consisting of acetonitril and ammonium acetate buffer set at flow rate 1.5 ml/min. The analyte was detected and quantified at 278nm using ultraviolet detector. The method was validated as per ICH guidelines. Results: The standard curve was found to have a linear relationship (r2 > 0.99 over the analytical range of 125–2000ng/ml. For all quality control (QC standards in intraday and interday assay, accuracy and precision range were -0.96 to 6.30 and 0.86 to 13.74 respectively, demonstrating the precision and accuracy over the analytical range. Samples were stable during preparation and analysis procedure. Conclusion: Therefore the rapid and sensitive developed method can be used for the routine analysis of sirolimus such as dissolution and stability assays of pre- and post-marketed dosage forms.

  1. Selenium contaminated waters: An overview of analytical methods, treatment options and recent advances in sorption methods.

    Science.gov (United States)

    Santos, Sílvia; Ungureanu, Gabriela; Boaventura, Rui; Botelho, Cidália

    2015-07-15

    Selenium is an essential trace element for many organisms, including humans, but it is bioaccumulative and toxic at higher than homeostatic levels. Both selenium deficiency and toxicity are problems around the world. Mines, coal-fired power plants, oil refineries and agriculture are important examples of anthropogenic sources, generating contaminated waters and wastewaters. For reasons of human health and ecotoxicity, selenium concentration has to be controlled in drinking-water and in wastewater, as it is a potential pollutant of water bodies. This review article provides firstly a general overview about selenium distribution, sources, chemistry, toxicity and environmental impact. Analytical techniques used for Se determination and speciation and water and wastewater treatment options are reviewed. In particular, published works on adsorption as a treatment method for Se removal from aqueous solutions are critically analyzed. Recent published literature has given particular attention to the development and search for effective adsorbents, including low-cost alternative materials. Published works mostly consist in exploratory findings and laboratory-scale experiments. Binary metal oxides and LDHs (layered double hydroxides) have presented excellent adsorption capacities for selenium species. Unconventional sorbents (algae, agricultural wastes and other biomaterials), in raw or modified forms, have also led to very interesting results with the advantage of their availability and low-cost. Some directions to be considered in future works are also suggested. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Development and validation of a thin-layer chromatography method for stability studies of naproxen

    International Nuclear Information System (INIS)

    Rodriguez Hernandez, Yaslenis; Suarez Perez, Yania; Garcia Pulpeiro, Oscar; Rodriguez Borges, Tania

    2011-01-01

    The validation of an analytical method was carried out to be applied to the stability studies of the future formulations of naproxen suppositories for infant and adult use. The factors which mostly influenced in the naproxen stability were determined, the major degradation occurred in oxidizing acid medium and by action of light. The possible formation of esters between the free carboxyl group present in naproxen and the glyceryl monoestereate present in the base was identified as one of the degradation paths in the new formulation. The results were satisfactory. A thin-layer chromatography-based method was developed as well as the best chromatographic conditions were selected. GF 254 silica gel plates and ultraviolet developer at 254 nm were employed. Three solvent systems were evaluated of which A made up of glacial acetic: tetrahydrofurane:toluene (3:9:90 v/v/v)allowed adequate resolution between the analyte and the possible degradation products, with detection limit of 1 μg. The use of the suggested method was restricted to the identification of possible degradation products just for qualitative purposes and not as final test. The method proved to be sensitive and selective enough to be applied for the stated objective, according to the validation results

  3. A Validated HPLC-DAD Method for Simultaneous Determination of Etodolac and Pantoprazole in Rat Plasma

    Directory of Open Access Journals (Sweden)

    Ali S. Abdelhameed

    2014-01-01

    Full Text Available A simple, sensitive, and accurate HPLC-DAD method has been developed and validated for the simultaneous determination of pantoprazole and etodolac in rat plasma as a tool for therapeutic drug monitoring. Optimal chromatographic separation of the analytes was achieved on a Waters Symmetry C18 column using a mobile phase that consisted of phosphate buffer pH~4.0 as eluent A and acetonitrile as eluent B in a ratio of A : B, 55 : 45 v/v for 6 min, pumped isocratically at a flow rate of 0.8 mL min−1. The eluted analytes were monitored using photodiode array detector set to quantify samples at 254 nm. The method was linear with r2=0.9999 for PTZ and r2=0.9995 for ETD at a concentration range of 0.1–15 and 5–50 μgmL−1 for PTZ and ETD, respectively. The limits of detection were found to be 0.033 and 0.918 μgmL−1 for PTZ and ETD, respectively. The method was statistically validated for linearity, accuracy, precision, and selectivity following the International Conference for Harmonization (ICH guidelines. The reproducibility of the method was reliable with the intra- and interday precision (% RSD <7.76% for PTZ and <7.58 % for ETD.

  4. Method development and validation for dieckol in the standardization of phlorotannin preparations

    Directory of Open Access Journals (Sweden)

    Jiyoung Kim

    2016-03-01

    Full Text Available Abstract Phlorotannins are reported to have diverse biological properties. However, no analytical methods for the standardization of phlorotannin preparations have been reported. Herein, we developed and validated an analytical method for the determination of dieckol in phlorotannin extracts (PRT using high-performance liquid chromatography (HPLC. The optimum HPLC conditions consisted of a Supelco Discovery C18 column stationary phase, a mobile phase (A: 15 % HPLC grade methanol in deionized water, B: methanol, UV detection at 230 nm, and a flow rate of 0.7 mL/min. The optimized chromatographic conditions were validated and exhibited good specificity and linearity (R 2 > 0.9994–1.0000. The recoveries were in the range of 100.9–102.3 %. The method had good intermediate (%RSD 1.2 and intra-day (%RSD 0.4–1.7 assay precisions. This HPLC method had good accuracy and quality in the determination of dieckol in PRT.

  5. MULTIPLE CRITERA METHODS WITH FOCUS ON ANALYTIC HIERARCHY PROCESS AND GROUP DECISION MAKING

    Directory of Open Access Journals (Sweden)

    Lidija Zadnik-Stirn

    2010-12-01

    Full Text Available Managing natural resources is a group multiple criteria decision making problem. In this paper the analytic hierarchy process is the chosen method for handling the natural resource problems. The one decision maker problem is discussed and, three methods: the eigenvector method, data envelopment analysis method, and logarithmic least squares method are presented for the derivation of the priority vector. Further, the group analytic hierarchy process is discussed and six methods for the aggregation of individual judgments or priorities: weighted arithmetic mean method, weighted geometric mean method, and four methods based on data envelopment analysis are compared. The case study on land use in Slovenia is applied. The conclusions review consistency, sensitivity analyses, and some future directions of research.

  6. Assessing the impact of natural policy experiments on socioeconomic inequalities in health: how to apply commonly used quantitative analytical methods?

    Science.gov (United States)

    Hu, Yannan; van Lenthe, Frank J; Hoffmann, Rasmus; van Hedel, Karen; Mackenbach, Johan P

    2017-04-20

    The scientific evidence-base for policies to tackle health inequalities is limited. Natural policy experiments (NPE) have drawn increasing attention as a means to evaluating the effects of policies on health. Several analytical methods can be used to evaluate the outcomes of NPEs in terms of average population health, but it is unclear whether they can also be used to assess the outcomes of NPEs in terms of health inequalities. The aim of this study therefore was to assess whether, and to demonstrate how, a number of commonly used analytical methods for the evaluation of NPEs can be applied to quantify the effect of policies on health inequalities. We identified seven quantitative analytical methods for the evaluation of NPEs: regression adjustment, propensity score matching, difference-in-differences analysis, fixed effects analysis, instrumental variable analysis, regression discontinuity and interrupted time-series. We assessed whether these methods can be used to quantify the effect of policies on the magnitude of health inequalities either by conducting a stratified analysis or by including an interaction term, and illustrated both approaches in a fictitious numerical example. All seven methods can be used to quantify the equity impact of policies on absolute and relative inequalities in health by conducting an analysis stratified by socioeconomic position, and all but one (propensity score matching) can be used to quantify equity impacts by inclusion of an interaction term between socioeconomic position and policy exposure. Methods commonly used in economics and econometrics for the evaluation of NPEs can also be applied to assess the equity impact of policies, and our illustrations provide guidance on how to do this appropriately. The low external validity of results from instrumental variable analysis and regression discontinuity makes these methods less desirable for assessing policy effects on population-level health inequalities. Increased use of the

  7. Analytical method for reconstruction pin to pin of the nuclear power density distribution

    International Nuclear Information System (INIS)

    Pessoa, Paulo O.; Silva, Fernando C.; Martinez, Aquilino S.

    2013-01-01

    An accurate and efficient method for reconstructing pin to pin of the nuclear power density distribution, involving the analytical solution of the diffusion equation for two-dimensional neutron energy groups in homogeneous nodes, is presented. The boundary conditions used for analytic as solution are the four currents or fluxes on the surface of the node, which are obtained by Nodal Expansion Method (known as NEM) and four fluxes at the vertices of a node calculated using the finite difference method. The analytical solution found is the homogeneous distribution of neutron flux. Detailed distributions pin to pin inside a fuel assembly are estimated by the product of homogeneous flux distribution by local heterogeneous form function. Furthermore, the form functions of flux and power are used. The results obtained with this method have a good accuracy when compared with reference values. (author)

  8. Analytical method for reconstruction pin to pin of the nuclear power density distribution

    Energy Technology Data Exchange (ETDEWEB)

    Pessoa, Paulo O.; Silva, Fernando C.; Martinez, Aquilino S., E-mail: ppessoa@con.ufrj.br, E-mail: fernando@con.ufrj.br, E-mail: aquilino@imp.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    An accurate and efficient method for reconstructing pin to pin of the nuclear power density distribution, involving the analytical solution of the diffusion equation for two-dimensional neutron energy groups in homogeneous nodes, is presented. The boundary conditions used for analytic as solution are the four currents or fluxes on the surface of the node, which are obtained by Nodal Expansion Method (known as NEM) and four fluxes at the vertices of a node calculated using the finite difference method. The analytical solution found is the homogeneous distribution of neutron flux. Detailed distributions pin to pin inside a fuel assembly are estimated by the product of homogeneous flux distribution by local heterogeneous form function. Furthermore, the form functions of flux and power are used. The results obtained with this method have a good accuracy when compared with reference values. (author)

  9. Assessment of Two Analytical Methods in Solving the Linear and Nonlinear Elastic Beam Deformation Problems

    DEFF Research Database (Denmark)

    Barari, Amin; Ganjavi, B.; Jeloudar, M. Ghanbari

    2010-01-01

    Purpose – In the last two decades with the rapid development of nonlinear science, there has appeared ever-increasing interest of scientists and engineers in the analytical techniques for nonlinear problems. This paper considers linear and nonlinear systems that are not only regarded as general...... boundary value problems, but also are used as mathematical models in viscoelastic and inelastic flows. The purpose of this paper is to present the application of the homotopy-perturbation method (HPM) and variational iteration method (VIM) to solve some boundary value problems in structural engineering...... and fluid mechanics. Design/methodology/approach – Two new but powerful analytical methods, namely, He's VIM and HPM, are introduced to solve some boundary value problems in structural engineering and fluid mechanics. Findings – Analytical solutions often fit under classical perturbation methods. However...

  10. Origin Determination and Differentiation of Gelatin Species of Bovine, Porcine, and Piscine through Analytical Methods

    Directory of Open Access Journals (Sweden)

    Hatice Saadiye Eryılmaz

    2017-06-01

    Full Text Available Gelatin origin determination has been a crucial issue with respect to religion and health concerns. It is necessary to analyze the origin of gelatin with reliable methods to ensure not only consumer choices but also safety and legal requirements such as labeling. There are many analytical methods developed for detection and/or quantification of gelatin from different sources including bovine, porcine and piscine. These analytical methods can be divided into physicochemical, chromatographic, immunochemical, spectroscopic and molecular methods. Moreover, computational methods have been used in some cases consecutively to ensure sensitivity of the analytical methods. Every method has different advantages and limitations due to their own principles, applied food matrix and process conditions of material. The present review intends to give insight into novel analytical methods and perspectives that have been developed to differentiate porcine, bovine and piscine gelatins and to establish their authenticity. Almost every method can be succeeded in origin determination; however, it is a matter of sensitivity in that some researches fail to ensure sufficient differentiation.

  11. Validation of ascorbic acid tablets of national production by igh-performance liquid chromatography method

    International Nuclear Information System (INIS)

    Rodriguez Hernandez, Yaslenis; Suarez Perez, Yania; Izquierdo Castro, Idalberto

    2009-01-01

    We validate an analytical method by high-performance liquid chromatography to determine ascorbic acid proportion in vitamin C tablets, which was designed as an alternative method to quality control and to follow-up of active principle chemical stability, since official techniques to quality control of ascorbic acid in tablets are not selective with degradation products. Method was modified according to that reported in USP 28, 2005 for analysis of injectable product. We used a RP-18 column of 250 x 4.6 mm 5 μm with a UV detector to 245 nm. Its validation was necessary for both objectives, considering parameters required for methods of I and II categories. This method was enough linear, exact, and precise in the rank of 100-300 μg/mL. Also, it was selective with remaining components of matrix and with the possible degradation products achieved in stressing conditions. Detection and quantification limits were estimated. When method was validated it was applied to ascorbic acid quantification in two batches of expired tablets and we detected a marked influence of container in active degradation principle after 12 months at room temperature. (Author)

  12. Pre-analytical and analytical validations and clinical applications of a miniaturized, simple and cost-effective solid phase extraction combined with LC-MS/MS for the simultaneous determination of catecholamines and metanephrines in spot urine samples.

    Science.gov (United States)

    Li, Xiaoguang Sunny; Li, Shu; Kellermann, Gottfried

    2016-10-01

    It remains a challenge to simultaneously quantify catecholamines and metanephrines in a simple, sensitive and cost-effective manner due to pre-analytical and analytical constraints. Herein, we describe such a method consisting of a miniaturized sample preparation and selective LC-MS/MS detection by the use of second morning spot urine samples. Ten microliters of second morning urine sample were subjected to solid phase extraction on an Oasis HLB microplate upon complexation with phenylboronic acid. The analytes were well-resolved on a Luna PFP column followed by tandem mass spectrometric detection. Full validation and suitability of spot urine sampling and biological variation were investigated. The extraction recovery and matrix effect are 74.1-97.3% and 84.1-119.0%, respectively. The linearity range is 2.5-500, 0.5-500, 2.5-1250, 2.5-1250 and 0.5-1250ng/mL for norepinephrine, epinephrine, dopamine, normetanephrine and metanephrine, respectively. The intra- and inter-assay imprecisions are ≤9.4% for spiked quality control samples, and the respective recoveries are 97.2-112.5% and 95.9-104.0%. The Deming regression slope is 0.90-1.08, and the mean Bland-Altman percentage difference is from -3.29 to 11.85 between a published and proposed method (n=50). A correlation observed for the spot and 24h urine collections is significant (n=20, p<0.0001, r: 0.84-0.95, slope: 0.61-0.98). No statistical differences are found in day-to-day biological variability (n=20). Reference intervals are established for an apparently healthy population (n=88). The developed method, being practical, sensitive, reliable and cost-effective, is expected to set a new stage for routine testing, basic research and clinical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Development and Validation of a Path Analytic Model of Students' Performance in Chemistry.

    Science.gov (United States)

    Anamuah-Mensah, Jophus; And Others

    1987-01-01

    Reported the development and validation of an integrated model of performance on chemical concept-volumetric analysis. Model was tested on 265 chemistry students in eight schools.Results indicated that for subjects using algorithms without understanding, performance on volumetric analysis problems was not influenced by proportional reasoning…

  14. The international validation of bio- and chemical-anlaytical screening methods for dioxins and dioxin-like PCBs: the DIFFERENCE project rounds 1 and 2

    NARCIS (Netherlands)

    Loco, van J.; Leeuwen, van S.P.J.; Roos, P.; Carbonnelle, S.; Boer, de J.; Goeyens, L.; Beernaert, H.

    2004-01-01

    The European research project DIFFERENCE is focussed on the development, optimisation and validation of screening methods for dioxin analysis, including bio-analytical and chemical techniques (CALUX, GC-LRMS/MS, GC x GC-ECD) and on the optimisation and validation of new extraction and clean-up

  15. Investigation of Unbalanced Magnetic Force in Magnetic Geared Machine Using Analytical Methods

    DEFF Research Database (Denmark)

    Zhang, Xiaoxu; Liu, Xiao; Chen, Zhe

    2016-01-01

    The electromagnetic structure of the magnetic geared machine (MGM) may induce a significant unbalanced magnetic force (UMF). However, few methods have been developed to theoretically reveal the essential reasons for this issue in the MGM. In this paper, an analytical method based on an air...

  16. Flammable gas safety program. Analytical methods development: FY 1994 progress report

    International Nuclear Information System (INIS)

    Campbell, J.A.; Clauss, S.; Grant, K.; Hoopes, V.; Lerner, B.; Lucke, R.; Mong, G.; Rau, J.; Wahl, K.; Steele, R.

    1994-09-01

    This report describes the status of developing analytical methods to account for the organic components in Hanford waste tanks, with particular focus on tanks assigned to the Flammable Gas Watch List. The methods that have been developed are illustrated by their application to samples obtained from Tank 241-SY-101 (Tank 101-SY)

  17. On Approximate Analytical Solutions of Nonlinear Vibrations of Inextensible Beams using Parameter-Expansion Method

    DEFF Research Database (Denmark)

    Kimiaeifar, Amin; Lund, Erik; Thomsen, Ole Thybo

    2010-01-01

    In this work, an analytical method, which is referred to as Parameter-expansion Method is used to obtain the exact solution for the problem of nonlinear vibrations of an inextensible beam. It is shown that one term in the series expansion is sufficient to obtain a highly accurate solution, which...

  18. EVALUATION OF ANALYTICAL METHODS FOR DETERMINING PESTICIDES IN BABY FOOD AND ADULT DUPLICATE-DIET SAMPLES

    Science.gov (United States)

    Determinations of pesticides in food are often complicated by the presence of fats and require multiple cleanup steps before analysis. Cost-effective analytical methods are needed for conducting large-scale exposure studies. We examined two extraction methods, supercritical flu...

  19. 2D Stabilised analytic signal method in DC pole-pole potential data ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Using analytic signal method, interpretation of pole-pole secondary electric potentials due to 2D conductive/resistive prisms is presented. The estimated parameters are the location, lateral extent or width and depth to top surface of the prism. Forward modelling is attempted by 2D-Finite. Difference method. The proposed ...

  20. An Analytical Investigation of Three General Methods of Calculating Chemical-Equilibrium Compositions

    Science.gov (United States)

    Zeleznik, Frank J.; Gordon, Sanford

    1960-01-01

    The Brinkley, Huff, and White methods for chemical-equilibrium calculations were modified and extended in order to permit an analytical comparison. The extended forms of these methods permit condensed species as reaction products, include temperature as a variable in the iteration, and permit arbitrary estimates for the variables. It is analytically shown that the three extended methods can be placed in a form that is independent of components. In this form the Brinkley iteration is identical computationally to the White method, while the modified Huff method differs only'slightly from these two. The convergence rates of the modified Brinkley and White methods are identical; and, further, all three methods are guaranteed to converge and will ultimately converge quadratically. It is concluded that no one of the three methods offers any significant computational advantages over the other two.