Science.gov

Sample records for advanced analytical methods

  1. Advanced epidemiologic and analytical methods.

    PubMed

    Albanese, E

    2016-01-01

    Observational studies are indispensable for etiologic research, and are key to test life-course hypotheses and improve our understanding of neurologic diseases that have long induction and latency periods. In recent years a plethora of advanced design and analytic techniques have been developed to strengthen the robustness and ultimately the validity of the results of observational studies, and to address their inherent proneness to bias. It is the responsibility of clinicians and researchers to critically appraise and appropriately contextualize the findings of the exponentially expanding scientific literature. This critical appraisal should be rooted in a thorough understanding of advanced epidemiologic methods and techniques commonly used to formulate and test relevant hypotheses and to keep bias at bay. PMID:27637951

  2. Recent advances in analytical methods for mycotoxins.

    PubMed

    Gilbert, J

    1993-01-01

    Recent advances in analytical methods are reviewed using the examples of aflatoxins and trichothecene mycotoxins. The most dramatic advances are seen as being those based on immunological principles utilized for aflatoxins to produce simple screening methods and for rapid specific clean-up. The possibilities of automation using immunoaffinity columns is described. In contrast for the trichothecenes immunological methods have not had the same general impact. Post-column derivatization using bromine or iodine to enhance fluorescence for HPLC detection of aflatoxins has become widely employed and there are similar possibilities for improved HPLC detection for trichothecenes using electrochemical or trichothecene-specific post-column reactions. There have been improvements in the use of more rapid and specific clean-up methods for trichothecenes, whilst HPLC and GC remain equally favoured for the end-determination. More sophisticated instrumental techniques such as mass spectrometry (LC/MS, MS/MS) and supercritical fluid chromatography (SFC/MS) have been demonstrated to have potential for application to mycotoxin analysis, but have not as yet made much general impact.

  3. Analytical and numerical methods; advanced computer concepts

    SciTech Connect

    Lax, P D

    1991-03-01

    This past year, two projects have been completed and a new is under way. First, in joint work with R. Kohn, we developed a numerical algorithm to study the blowup of solutions to equations with certain similarity transformations. In the second project, the adaptive mesh refinement code of Berger and Colella for shock hydrodynamic calculations has been parallelized and numerical studies using two different shared memory machines have been done. My current effort is towards the development of Cartesian mesh methods to solve pdes with complicated geometries. Most of the coming year will be spent on this project, which is joint work with Prof. Randy Leveque at the University of Washington in Seattle.

  4. Advanced and In Situ Analytical Methods for Solar Fuel Materials.

    PubMed

    Chan, Candace K; Tüysüz, Harun; Braun, Artur; Ranjan, Chinmoy; La Mantia, Fabio; Miller, Benjamin K; Zhang, Liuxian; Crozier, Peter A; Haber, Joel A; Gregoire, John M; Park, Hyun S; Batchellor, Adam S; Trotochaud, Lena; Boettcher, Shannon W

    2016-01-01

    In situ and operando techniques can play important roles in the development of better performing photoelectrodes, photocatalysts, and electrocatalysts by helping to elucidate crucial intermediates and mechanistic steps. The development of high throughput screening methods has also accelerated the evaluation of relevant photoelectrochemical and electrochemical properties for new solar fuel materials. In this chapter, several in situ and high throughput characterization tools are discussed in detail along with their impact on our understanding of solar fuel materials.

  5. Advances in analytical chemistry

    NASA Technical Reports Server (NTRS)

    Arendale, W. F.; Congo, Richard T.; Nielsen, Bruce J.

    1991-01-01

    Implementation of computer programs based on multivariate statistical algorithms makes possible obtaining reliable information from long data vectors that contain large amounts of extraneous information, for example, noise and/or analytes that we do not wish to control. Three examples are described. Each of these applications requires the use of techniques characteristic of modern analytical chemistry. The first example, using a quantitative or analytical model, describes the determination of the acid dissociation constant for 2,2'-pyridyl thiophene using archived data. The second example describes an investigation to determine the active biocidal species of iodine in aqueous solutions. The third example is taken from a research program directed toward advanced fiber-optic chemical sensors. The second and third examples require heuristic or empirical models.

  6. Selenium contaminated waters: An overview of analytical methods, treatment options and recent advances in sorption methods.

    PubMed

    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. PMID:25847169

  7. Selenium contaminated waters: An overview of analytical methods, treatment options and recent advances in sorption methods.

    PubMed

    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.

  8. Biological Matrix Effects in Quantitative Tandem Mass Spectrometry-Based Analytical Methods: Advancing Biomonitoring

    PubMed Central

    Panuwet, Parinya; Hunter, Ronald E.; D’Souza, Priya E.; Chen, Xianyu; Radford, Samantha A.; Cohen, Jordan R.; Marder, M. Elizabeth; Kartavenka, Kostya; Ryan, P. Barry; Barr, Dana Boyd

    2015-01-01

    The ability to quantify levels of target analytes in biological samples accurately and precisely, in biomonitoring, involves the use of highly sensitive and selective instrumentation such as tandem mass spectrometers and a thorough understanding of highly variable matrix effects. Typically, matrix effects are caused by co-eluting matrix components that alter the ionization of target analytes as well as the chromatographic response of target analytes, leading to reduced or increased sensitivity of the analysis. Thus, before the desired accuracy and precision standards of laboratory data are achieved, these effects must be characterized and controlled. Here we present our review and observations of matrix effects encountered during the validation and implementation of tandem mass spectrometry-based analytical methods. We also provide systematic, comprehensive laboratory strategies needed to control challenges posed by matrix effects in order to ensure delivery of the most accurate data for biomonitoring studies assessing exposure to environmental toxicants. PMID:25562585

  9. Extraction, Analytical and Advanced Methods for Detection of Allura Red AC (E129) in Food and Beverages Products

    PubMed Central

    Rovina, Kobun; Siddiquee, Shafiquzzaman; Shaarani, Sharifudin M.

    2016-01-01

    Allura Red AC (E129) is an azo dye that widely used in drinks, juices, bakery, meat, and sweets products. High consumption of Allura Red has claimed an adverse effects of human health including allergies, food intolerance, cancer, multiple sclerosis, attention deficit hyperactivity disorder, brain damage, nausea, cardiac disease and asthma due to the reaction of aromatic azo compounds (R = R′ = aromatic). Several countries have banned and strictly controlled the uses of Allura Red in food and beverage products. This review paper is critically summarized on the available analytical and advanced methods for determination of Allura Red and also concisely discussed on the acceptable daily intake, toxicology and extraction methods. PMID:27303385

  10. Extraction, Analytical and Advanced Methods for Detection of Allura Red AC (E129) in Food and Beverages Products.

    PubMed

    Rovina, Kobun; Siddiquee, Shafiquzzaman; Shaarani, Sharifudin M

    2016-01-01

    Allura Red AC (E129) is an azo dye that widely used in drinks, juices, bakery, meat, and sweets products. High consumption of Allura Red has claimed an adverse effects of human health including allergies, food intolerance, cancer, multiple sclerosis, attention deficit hyperactivity disorder, brain damage, nausea, cardiac disease and asthma due to the reaction of aromatic azo compounds (R = R' = aromatic). Several countries have banned and strictly controlled the uses of Allura Red in food and beverage products. This review paper is critically summarized on the available analytical and advanced methods for determination of Allura Red and also concisely discussed on the acceptable daily intake, toxicology and extraction methods. PMID:27303385

  11. Advanced organic analysis and analytical methods development: FY 1995 progress report. Waste Tank Organic Safety Program

    SciTech Connect

    Wahl, K.L.; Campbell, J.A.; Clauss, S.A.

    1995-09-01

    This report describes the work performed during FY 1995 by Pacific Northwest Laboratory in developing and optimizing analysis techniques for identifying organics present in Hanford waste tanks. The main focus was to provide a means for rapidly obtaining the most useful information concerning the organics present in tank waste, with minimal sample handling and with minimal waste generation. One major focus has been to optimize analytical methods for organic speciation. Select methods, such as atmospheric pressure chemical ionization mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry, were developed to increase the speciation capabilities, while minimizing sample handling. A capillary electrophoresis method was developed to improve separation capabilities while minimizing additional waste generation. In addition, considerable emphasis has been placed on developing a rapid screening tool, based on Raman and infrared spectroscopy, for determining organic functional group content when complete organic speciation is not required. This capability would allow for a cost-effective means to screen the waste tanks to identify tanks that require more specialized and complete organic speciation to determine tank safety.

  12. The development and application of advanced analytical methods to commercial ICF reactor chambers. Final report

    SciTech Connect

    Cousseau, P.; Engelstad, R.; Henderson, D.L.

    1997-10-01

    Progress is summarized in this report for each of the following tasks: (1) multi-dimensional radiation hydrodynamics computer code development; (2) 2D radiation-hydrodynamic code development; (3) ALARA: analytic and Laplacian adaptive radioactivity analysis -- a complete package for analysis of induced activation; (4) structural dynamics modeling of ICF reactor chambers; and (5) analysis of self-consistent target chamber clearing.

  13. Validating Analytical Methods

    ERIC Educational Resources Information Center

    Ember, Lois R.

    1977-01-01

    The procedures utilized by the Association of Official Analytical Chemists (AOAC) to develop, evaluate, and validate analytical methods for the analysis of chemical pollutants are detailed. Methods validated by AOAC are used by the EPA and FDA in their enforcement programs and are granted preferential treatment by the courts. (BT)

  14. Advances in the analytical methods for determining the antioxidant properties of honey: a review.

    PubMed

    Moniruzzaman, M; Khalil, M I; Sulaiman, S A; Gan, S H

    2012-01-01

    Free radicals and reactive oxygen species (ROS) have been implicated in contributing to the processes of aging and disease. In an effort to combat free radical activity, scientists are studying the effects of increasing individuals' antioxidant levels through diet and dietary supplements. Honey appears to act as an antioxidant in more ways than one. In the body, honey can mop up free radicals and contribute to better health. Various antioxidant activity methods have been used to measure and compare the antioxidant activity of honey. In recent years, DPPH (Diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power), ORAC (The Oxygen Radical Absorbance Capacity), ABTS [2, 2-azinobis (3ehtylbenzothiazoline-6-sulfonic acid) diamonium salt], TEAC [6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid (Trolox)-equivalent antioxidant capacity] assays have been used to evaluate antioxidant activity of honey. The antioxidant activity of honey is also measured by ascorbic acid content and different enzyme assays like Catalase (CAT), Glutathione Peroxidase (GPO), Superoxide Dismutase (SOD). Among the different methods available, methods that have been validated, standardized and widely reported are recommended.

  15. Analytic Methods in Investigative Geometry.

    ERIC Educational Resources Information Center

    Dobbs, David E.

    2001-01-01

    Suggests an alternative proof by analytic methods, which is more accessible than rigorous proof based on Euclid's Elements, in which students need only apply standard methods of trigonometry to the data without introducing new points or lines. (KHR)

  16. Advances in analytical methods and occurrence of organic UV-filters in the environment--A review.

    PubMed

    Ramos, Sara; Homem, Vera; Alves, Arminda; Santos, Lúcia

    2015-09-01

    UV-filters are a group of compounds designed mainly to protect skin against UVA and UVB radiation, but they are also included in plastics, furniture, etc., to protect products from light damage. Their massive use in sunscreens for skin protection has been increasing due to the awareness of the chronic and acute effects of UV radiation. Some organic UV-filters have raised significant concerns in the past few years for their continuous usage, persistent input and potential threat to ecological environment and human health. UV-filters end up in wastewater and because wastewater treatment plants are not efficient in removing them, lipophilic compounds tend to sorb onto sludge and hydrophilics end up in river water, contaminating the existing biota. To better understand the risk associated with UV-filters in the environment a thorough review regarding their physicochemical properties, toxicity and environmental degradation, analytical methods and their occurrence was conducted. Higher UV-filter concentrations were found in rivers, reaching 0.3mg/L for the most studied family, the benzophenone derivatives. Concentrations in the ng to μg/L range were also detected for the p-aminobenzoic acid, cinnamate, crylene and benzoyl methane derivatives in lake and sea water. Although at lower levels (few ng/L), UV-filters were also found in tap and groundwater. Swimming pool water is also a sink for UV-filters and its chlorine by-products, at the μg/L range, highlighting the benzophenone and benzimidazole derivatives. Soils and sediments are not frequently studied, but concentrations in the μg/L range have already been found especially for the benzophenone and crylene derivatives. Aquatic biota is frequently studied and UV-filters are found in the ng/g-dw range with higher values for fish and mussels. It has been concluded that more information regarding UV-filter degradation studies both in water and sediments is necessary and environmental occurrences should be monitored more

  17. Advances in analytical methods and occurrence of organic UV-filters in the environment--A review.

    PubMed

    Ramos, Sara; Homem, Vera; Alves, Arminda; Santos, Lúcia

    2015-09-01

    UV-filters are a group of compounds designed mainly to protect skin against UVA and UVB radiation, but they are also included in plastics, furniture, etc., to protect products from light damage. Their massive use in sunscreens for skin protection has been increasing due to the awareness of the chronic and acute effects of UV radiation. Some organic UV-filters have raised significant concerns in the past few years for their continuous usage, persistent input and potential threat to ecological environment and human health. UV-filters end up in wastewater and because wastewater treatment plants are not efficient in removing them, lipophilic compounds tend to sorb onto sludge and hydrophilics end up in river water, contaminating the existing biota. To better understand the risk associated with UV-filters in the environment a thorough review regarding their physicochemical properties, toxicity and environmental degradation, analytical methods and their occurrence was conducted. Higher UV-filter concentrations were found in rivers, reaching 0.3mg/L for the most studied family, the benzophenone derivatives. Concentrations in the ng to μg/L range were also detected for the p-aminobenzoic acid, cinnamate, crylene and benzoyl methane derivatives in lake and sea water. Although at lower levels (few ng/L), UV-filters were also found in tap and groundwater. Swimming pool water is also a sink for UV-filters and its chlorine by-products, at the μg/L range, highlighting the benzophenone and benzimidazole derivatives. Soils and sediments are not frequently studied, but concentrations in the μg/L range have already been found especially for the benzophenone and crylene derivatives. Aquatic biota is frequently studied and UV-filters are found in the ng/g-dw range with higher values for fish and mussels. It has been concluded that more information regarding UV-filter degradation studies both in water and sediments is necessary and environmental occurrences should be monitored more

  18. NC CATCH: Advancing Public Health Analytics.

    PubMed

    Studnicki, James; Fisher, John W; Eichelberger, Christopher; Bridger, Colleen; Angelon-Gaetz, Kim; Nelson, Debi

    2010-01-01

    The North Carolina Comprehensive Assessment for Tracking Community Health (NC CATCH) is a Web-based analytical system deployed to local public health units and their community partners. The system has the following characteristics: flexible, powerful online analytic processing (OLAP) interface; multiple sources of multidimensional, event-level data fully conformed to common definitions in a data warehouse structure; enabled utilization of available decision support software tools; analytic capabilities distributed and optimized locally with centralized technical infrastructure; two levels of access differentiated by the user (anonymous versus registered) and by the analytical flexibility (Community Profile versus Design Phase); and, an emphasis on user training and feedback. The ability of local public health units to engage in outcomes-based performance measurement will be influenced by continuing access to event-level data, developments in evidence-based practice for improving population health, and the application of information technology-based analytic tools and methods.

  19. Advances in text analytics for drug discovery.

    PubMed

    Roberts, Phoebe M; Hayes, William S

    2005-05-01

    The automated extraction of biological and chemical information has improved over the past year, with advances in access to content, entity extraction of genes, chemicals, kinetic data and relationships, and algorithms for generating and testing hypotheses. As the systems for reading and understanding scientific literature grow more powerful, so must the infrastructure in which to assemble information. Advances in infrastructure systems are discussed in this review. Research efforts have flourished as a result of text analytics competitions that attract participants from various disciplines, from computer science to bioinformatics.

  20. Analytical Methods for Online Searching.

    ERIC Educational Resources Information Center

    Vigil, Peter J.

    1983-01-01

    Analytical methods for facilitating comparison of multiple sets during online searching are illustrated by description of specific searching methods that eliminate duplicate citations and a factoring procedure based on syntactic relationships that establishes ranked sets. Searches executed in National Center for Mental Health database on…

  1. Analytical methods under emergency conditions

    SciTech Connect

    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. (ACR)

  2. Waste minimization in analytical methods

    SciTech Connect

    Green, D.W.; Smith, L.L.; Crain, J.S.; Boparai, A.S.; Kiely, J.T.; Yaeger, J.S. Schilling, J.B.

    1995-05-01

    The US Department of Energy (DOE) will require a large number of waste characterizations over a multi-year period to accomplish the Department`s goals in environmental restoration and waste management. Estimates vary, but two million analyses annually are expected. The waste generated by the analytical procedures used for characterizations is a significant source of new DOE waste. Success in reducing the volume of secondary waste and the costs of handling this waste would significantly decrease the overall cost of this DOE program. Selection of appropriate analytical methods depends on the intended use of the resultant data. It is not always necessary to use a high-powered analytical method, typically at higher cost, to obtain data needed to make decisions about waste management. Indeed, for samples taken from some heterogeneous systems, the meaning of high accuracy becomes clouded if the data generated are intended to measure a property of this system. Among the factors to be considered in selecting the analytical method are the lower limit of detection, accuracy, turnaround time, cost, reproducibility (precision), interferences, and simplicity. Occasionally, there must be tradeoffs among these factors to achieve the multiple goals of a characterization program. The purpose of the work described here is to add waste minimization to the list of characteristics to be considered. In this paper the authors present results of modifying analytical methods for waste characterization to reduce both the cost of analysis and volume of secondary wastes. Although tradeoffs may be required to minimize waste while still generating data of acceptable quality for the decision-making process, they have data demonstrating that wastes can be reduced in some cases without sacrificing accuracy or precision.

  3. Making advanced analytics work for you.

    PubMed

    Barton, Dominic; Court, David

    2012-10-01

    Senior leaders who write off the move toward big data as a lot of big talk are making, well, a big mistake. So argue McKinsey's Barton and Court, who worked with dozens of companies to figure out how to translate advanced analytics into nuts-and-bolts practices that affect daily operations on the front lines. The authors offer a useful guide for leaders and managers who want to take a deliberative approach to big data-but who also want to get started now. First, companies must identify the right data for their business, seek to acquire the information creatively from diverse sources, and secure the necessary IT support. Second, they need to build analytics models that are tightly focused on improving performance, making the models only as complex as business goals demand. Third, and most important, companies must transform their capabilities and culture so that the analytical results can be implemented from the C-suite to the front lines. That means developing simple tools that everyone in the organization can understand and teaching people why the data really matter. Embracing big data is as much about changing mind-sets as it is about crunching numbers. Executed with the right care and flexibility, this cultural shift could have payoffs that are, well, bigger than you expect.

  4. 7 CFR 94.303 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Analytical methods. 94.303 Section 94.303 Agriculture... POULTRY AND EGG PRODUCTS Processed Poultry Products § 94.303 Analytical methods. The analytical methods... latest edition of the Official Methods of Analysis of AOAC INTERNATIONAL, Suite 500, 481 North...

  5. 7 CFR 94.303 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 94.303 Section 94.303 Agriculture... POULTRY AND EGG PRODUCTS Processed Poultry Products § 94.303 Analytical methods. The analytical methods... latest edition of the Official Methods of Analysis of AOAC INTERNATIONAL, Suite 500, 481 North...

  6. 7 CFR 93.4 - Analytical methods.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... PROCESSED FRUITS AND VEGETABLES Citrus Juices and Certain Citrus Products § 93.4 Analytical methods. (a) The majority of analytical methods for citrus products are found in the Official Methods of Analysis of AOAC...-2417. (b) Other analytical methods for citrus products may be used as approved by the AMS...

  7. 7 CFR 93.4 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PROCESSED FRUITS AND VEGETABLES Citrus Juices and Certain Citrus Products § 93.4 Analytical methods. (a) The majority of analytical methods for citrus products are found in the Official Methods of Analysis of AOAC...-2417. (b) Other analytical methods for citrus products may be used as approved by the AMS...

  8. 7 CFR 93.4 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROCESSED FRUITS AND VEGETABLES Citrus Juices and Certain Citrus Products § 93.4 Analytical methods. (a) The majority of analytical methods for citrus products are found in the Official Methods of Analysis of AOAC...-2417. (b) Other analytical methods for citrus products may be used as approved by the AMS...

  9. 7 CFR 93.4 - Analytical methods.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... PROCESSED FRUITS AND VEGETABLES Citrus Juices and Certain Citrus Products § 93.4 Analytical methods. (a) The majority of analytical methods for citrus products are found in the Official Methods of Analysis of AOAC...-2417. (b) Other analytical methods for citrus products may be used as approved by the AMS...

  10. 7 CFR 93.4 - Analytical methods.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... PROCESSED FRUITS AND VEGETABLES Citrus Juices and Certain Citrus Products § 93.4 Analytical methods. (a) The majority of analytical methods for citrus products are found in the Official Methods of Analysis of AOAC...-2417. (b) Other analytical methods for citrus products may be used as approved by the AMS...

  11. 7 CFR 94.103 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Analytical methods. 94.103 Section 94.103 Agriculture... POULTRY AND EGG PRODUCTS Voluntary Analyses of Egg Products § 94.103 Analytical methods. The analytical methods used by the Science and Technology Division laboratories to perform voluntary analyses for...

  12. 7 CFR 94.103 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Analytical methods. 94.103 Section 94.103 Agriculture... POULTRY AND EGG PRODUCTS Voluntary Analyses of Egg Products § 94.103 Analytical methods. The analytical methods used by the Science and Technology Division laboratories to perform voluntary analyses for...

  13. 40 CFR 141.89 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Analytical methods. 141.89 Section 141...) NATIONAL PRIMARY DRINKING WATER REGULATIONS Control of Lead and Copper § 141.89 Analytical methods. (a... shall be conducted with the methods in § 141.23(k)(1). (1) Analyses for alkalinity,...

  14. 40 CFR 141.89 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Analytical methods. 141.89 Section 141...) NATIONAL PRIMARY DRINKING WATER REGULATIONS Control of Lead and Copper § 141.89 Analytical methods. (a... shall be conducted with the methods in § 141.23(k)(1). (1) Analyses for alkalinity,...

  15. Analytical advances in pharmaceutical impurity profiling.

    PubMed

    Holm, René; Elder, David P

    2016-05-25

    Impurities will be present in all drug substances and drug products, i.e. nothing is 100% pure if one looks in enough depth. The current regulatory guidance on impurities accepts this, and for drug products with a dose of less than 2g/day identification of impurities is set at 0.1% levels and above (ICH Q3B(R2), 2006). For some impurities, this is a simple undertaking as generally available analytical techniques can address the prevailing analytical challenges; whereas, for others this may be much more challenging requiring more sophisticated analytical approaches. The present review provides an insight into current development of analytical techniques to investigate and quantify impurities in drug substances and drug products providing discussion of progress particular within the field of chromatography to ensure separation of and quantification of those related impurities. Further, a section is devoted to the identification of classical impurities, but in addition, inorganic (metal residues) and solid state impurities are also discussed. Risk control strategies for pharmaceutical impurities aligned with several of the ICH guidelines, are also discussed.

  16. Recent advances in analytical satellite theory

    NASA Technical Reports Server (NTRS)

    Gaposchkin, E. M.

    1978-01-01

    Recent work on analytical satellite perturbation theory has involved the completion of a revision to 4th order for zonal harmonics, the addition of a treatment for ocean tides, an extension of the treatment for the noninertial reference system, and the completion of a theory for direct solar-radiation pressure and earth-albedo pressure. Combined with a theory for tesseral-harmonics, lunisolar, and body-tide perturbations, these formulations provide a comprehensive orbit-computation program. Detailed comparisons with numerical integration and observations are presented to assess the accuracy of each theoretical development.

  17. 7 CFR 91.23 - Analytical methods.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    .... Environmental Protection Agency (EPA) Chemical Exposure Research Branch, EPA Office of Research and Development... Evaluating Solid Waste Physical/Chemical Methods, Environmental Protection Agency, Office of Solid Waste, SW... and Engineering Center's Military Specifications, approved analytical test methods noted therein,...

  18. Method of identity analyte-binding peptides

    DOEpatents

    Kauvar, Lawrence M.

    1990-01-01

    A method for affinity chromatography or adsorption of a designated analyte utilizes a paralog as the affinity partner. The immobilized paralog can be used in purification or analysis of the analyte; the paralog can also be used as a substitute for antibody in an immunoassay. The paralog is identified by screening candidate peptide sequences of 4-20 amino acids for specific affinity to the analyte.

  19. Method of identity analyte-binding peptides

    DOEpatents

    Kauvar, L.M.

    1990-10-16

    A method for affinity chromatography or adsorption of a designated analyte utilizes a paralog as the affinity partner. The immobilized paralog can be used in purification or analysis of the analyte; the paralog can also be used as a substitute for antibody in an immunoassay. The paralog is identified by screening candidate peptide sequences of 4--20 amino acids for specific affinity to the analyte. 5 figs.

  20. Matrix Methods to Analytic Geometry.

    ERIC Educational Resources Information Center

    Bandy, C.

    1982-01-01

    The use of basis matrix methods to rotate axes is detailed. It is felt that persons who have need to rotate axes often will find that the matrix method saves considerable work. One drawback is that most students first learning to rotate axes will not yet have studied linear algebra. (MP)

  1. Method and apparatus for detecting an analyte

    DOEpatents

    Allendorf, Mark D.; Hesketh, Peter J.

    2011-11-29

    We describe the use of coordination polymers (CP) as coatings on microcantilevers for the detection of chemical analytes. CP exhibit changes in unit cell parameters upon adsorption of analytes, which will induce a stress in a static microcantilever upon which a CP layer is deposited. We also describe fabrication methods for depositing CP layers on surfaces.

  2. Fast optical proximity correction: analytical method

    NASA Astrophysics Data System (ADS)

    Shioiri, Satomi; Tanabe, Hiroyoshi

    1995-05-01

    In automating optical proximity correction, calculation speed becomes important. In this paper we present a novel method for calculating proximity corrected features analytically. The calculation will take only several times the amount it takes to calculate intensity of one point on wafer. Therefore, the calculation will become extremely faster than conventional repetitive aerial image calculations. This method is applied to a simple periodic pattern. The simulated results show great improvement on linearity after correction and have proved the effectiveness of this analytical method.

  3. 7 CFR 94.4 - Analytical methods.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., Gaithersburg, MD 20877-2417. (d) Manual of Analytical Methods for the Analysis of Pesticide Residues in Human...), Volumes I and II, Food and Drug Administration, Center for Food Safety and Applied Nutrition (CFSAN),...

  4. [Recent advancement of photonic-crystal-based analytical chemistry].

    PubMed

    Chen, Yun; Guo, Zhenpeng; Wang, Jinyi; Chen, Yi

    2014-04-01

    Photonic crystals are a type of novel materials with ordered structure, nanopores/channels and optical band gap. They have hence important applications in physics, chemistry, biological science and engineering fields. This review summarizes the recent advancement of photonic crystals in analytical chemistry applications, with focus on sensing and separating fields happening in the nearest 5 years.

  5. Analytical Methods for Trace Metals. Training Manual.

    ERIC Educational Resources Information Center

    Office of Water Program Operations (EPA), Cincinnati, OH. National Training and Operational Technology Center.

    This training manual presents material on the theoretical concepts involved in the methods listed in the Federal Register as approved for determination of trace metals. Emphasis is on laboratory operations. This course is intended for chemists and technicians with little or no experience in analytical methods for trace metals. Students should have…

  6. 7 CFR 93.13 - Analytical methods.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 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... Recommended Practices of the American Oil Chemists' Society (AOCS), American Oil Chemists' Society, P.O....

  7. 7 CFR 93.13 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 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... Recommended Practices of the American Oil Chemists' Society (AOCS), American Oil Chemists' Society, P.O....

  8. 7 CFR 93.13 - Analytical methods.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 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... Recommended Practices of the American Oil Chemists' Society (AOCS), American Oil Chemists' Society, P.O....

  9. 7 CFR 93.13 - Analytical methods.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 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... Recommended Practices of the American Oil Chemists' Society (AOCS), American Oil Chemists' Society, P.O....

  10. 7 CFR 93.13 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    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... Recommended Practices of the American Oil Chemists' Society (AOCS), American Oil Chemists' Society, P.O....

  11. Analytical Methods for Characterizing Magnetic Resonance Probes

    PubMed Central

    Manus, Lisa M.; Strauch, Renee C.; Hung, Andy H.; Eckermann, Amanda L.; Meade, Thomas J.

    2012-01-01

    SUMMARY The efficiency of Gd(III) contrast agents in magnetic resonance image enhancement is governed by a set of tunable structural parameters. Understanding and measuring these parameters requires specific analytical techniques. This Feature describes strategies to optimize each of the critical Gd(III) relaxation parameters for molecular imaging applications and the methods employed for their evaluation. PMID:22624599

  12. Prioritizing pesticide compounds for analytical methods development

    USGS Publications Warehouse

    Norman, Julia E.; Kuivila, Kathryn M.; 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

  13. Analytic sequential methods for detecting network intrusions

    NASA Astrophysics Data System (ADS)

    Chen, Xinjia; Walker, Ernest

    2014-05-01

    In this paper, we propose an analytic sequential methods for detecting port-scan attackers which routinely perform random "portscans" of IP addresses to find vulnerable servers to compromise. In addition to rigorously control the probability of falsely implicating benign remote hosts as malicious, our method performs significantly faster than other current solutions. We have developed explicit formulae for quick determination of the parameters of the new detection algorithm.

  14. An Analytical Method of Estimating Turbine Performance

    NASA Technical Reports Server (NTRS)

    Kochendorfer, Fred D; Nettles, J Cary

    1948-01-01

    A method is developed by which the performance of a turbine over a range of operating conditions can be analytically estimated from the blade angles and flow areas. In order to use the method, certain coefficients that determine the weight flow and friction losses must be approximated. The method is used to calculate the performance of the single-stage turbine of a commercial aircraft gas-turbine engine and the calculated performance is compared with the performance indicated by experimental data. For the turbine of the typical example, the assumed pressure losses and turning angles give a calculated performance that represents the trends of the experimental performance with reasonable accuracy. The exact agreement between analytical performance and experimental performance is contingent upon the proper selection of the blading-loss parameter. A variation of blading-loss parameter from 0.3 to 0.5 includes most of the experimental data from the turbine investigated.

  15. An analytical method of estimating turbine performance

    NASA Technical Reports Server (NTRS)

    Kochendorfer, Fred D; Nettles, J Cary

    1949-01-01

    A method is developed by which the performance of a turbine over a range of operating conditions can be analytically estimated from the blade angles and flow areas. In order to use the method, certain coefficients that determine the weight flow and the friction losses must be approximated. The method is used to calculate the performance of the single-stage turbine of a commercial aircraft gas-turbine engine and the calculated performance is compared with the performance indicated by experimental data. For the turbine of the typical example, the assumed pressure losses and the tuning angles give a calculated performance that represents the trends of the experimental performance with reasonable accuracy. The exact agreement between analytical performance and experimental performance is contingent upon the proper selection of a blading-loss parameter.

  16. Algorithmic and analytical methods in network biology.

    PubMed

    Koyutürk, Mehmet

    2010-01-01

    During the genomic revolution, algorithmic and analytical methods for organizing, integrating, analyzing, and querying biological sequence data proved invaluable. Today, increasing availability of high-throughput data pertaining to functional states of biomolecules, as well as their interactions, enables genome-scale studies of the cell from a systems perspective. The past decade witnessed significant efforts on the development of computational infrastructure for large-scale modeling and analysis of biological systems, commonly using network models. Such efforts lead to novel insights into the complexity of living systems, through development of sophisticated abstractions, algorithms, and analytical techniques that address a broad range of problems, including the following: (1) inference and reconstruction of complex cellular networks; (2) identification of common and coherent patterns in cellular networks, with a view to understanding the organizing principles and building blocks of cellular signaling, regulation, and metabolism; and (3) characterization of cellular mechanisms that underlie the differences between living systems, in terms of evolutionary diversity, development and differentiation, and complex phenotypes, including human disease. These problems pose significant algorithmic and analytical challenges because of the inherent complexity of the systems being studied; limitations of data in terms of availability, scope, and scale; intractability of resulting computational problems; and limitations of reference models for reliable statistical inference. This article provides a broad overview of existing algorithmic and analytical approaches to these problems, highlights key biological insights provided by these approaches, and outlines emerging opportunities and challenges in computational systems biology.

  17. Algorithmic and analytical methods in network biology

    PubMed Central

    Koyutürk, Mehmet

    2011-01-01

    During genomic revolution, algorithmic and analytical methods for organizing, integrating, analyzing, and querying biological sequence data proved invaluable. Today, increasing availability of high-throughput data pertaining functional states of biomolecules, as well as their interactions, enables genome-scale studies of the cell from a systems perspective. The past decade witnessed significant efforts on the development of computational infrastructure for large-scale modeling and analysis of biological systems, commonly using network models. Such efforts lead to novel insights into the complexity of living systems, through development of sophisticated abstractions, algorithms, and analytical techniques that address a broad range of problems, including the following: (1) inference and reconstruction of complex cellular networks; (2) identification of common and coherent patterns in cellular networks, with a view to understanding the organizing principles and building blocks of cellular signaling, regulation, and metabolism; and (3) characterization of cellular mechanisms that underlie the differences between living systems, in terms of evolutionary diversity, development and differentiation, and complex phenotypes, including human disease. These problems pose significant algorithmic and analytical challenges because of the inherent complexity of the systems being studied; limitations of data in terms of availability, scope, and scale; intractability of resulting computational problems; and limitations of reference models for reliable statistical inference. This article provides a broad overview of existing algorithmic and analytical approaches to these problems, highlights key biological insights provided by these approaches, and outlines emerging opportunities and challenges in computational systems biology. PMID:20836029

  18. Secondary waste minimization in analytical methods

    SciTech Connect

    Green, D.W.; Smith, L.L.; Crain, J.S.; Boparai, A.S.; Kiely, J.T.; Yaeger, J.S.; Schilling, J.B.

    1995-07-01

    The characterization phase of site remediation is an important and costly part of the process. Because toxic solvents and other hazardous materials are used in common analytical methods, characterization is also a source of new waste, including mixed waste. Alternative analytical methods can reduce the volume or form of hazardous waste produced either in the sample preparation step or in the measurement step. The authors are examining alternative methods in the areas of inorganic, radiological, and organic analysis. For determining inorganic constituents, alternative methods were studied for sample introduction into inductively coupled plasma spectrometers. Figures of merit for the alternative methods, as well as their associated waste volumes, were compared with the conventional approaches. In the radiological area, the authors are comparing conventional methods for gross {alpha}/{beta} measurements of soil samples to an alternative method that uses high-pressure microwave dissolution. For determination of organic constituents, microwave-assisted extraction was studied for RCRA regulated semivolatile organics in a variety of solid matrices, including spiked samples in blank soil; polynuclear aromatic hydrocarbons in soils, sludges, and sediments; and semivolatile organics in soil. Extraction efficiencies were determined under varying conditions of time, temperature, microwave power, moisture content, and extraction solvent. Solvent usage was cut from the 300 mL used in conventional extraction methods to about 30 mL. Extraction results varied from one matrix to another. In most cases, the microwave-assisted extraction technique was as efficient as the more common Soxhlet or sonication extraction techniques.

  19. Analytical Methods for Secondary Metabolite Detection.

    PubMed

    Taibon, Judith; Strasser, Hermann

    2016-01-01

    The entomopathogenic fungi Metarhizium brunneum, Beauveria bassiana, and B. brongniartii are widely applied as biological pest control agent in OECD countries. Consequently, their use has to be flanked by a risk management approach, which includes the need to monitor the fate of their relevant toxic metabolites. There are still data gaps claimed by regulatory authorities pending on their identification and quantification of relevant toxins or secondary metabolites. In this chapter, analytical methods are presented allowing the qualitative and quantitative analysis of the relevant toxic B. brongniartii metabolite oosporein and the three M. brunneum relevant destruxin (dtx) derivatives dtx A, dtx B, and dtx E. PMID:27565501

  20. Analytical chromatography. Methods, instrumentation and applications

    NASA Astrophysics Data System (ADS)

    Yashin, Ya I.; Yashin, A. Ya

    2006-04-01

    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.

  1. Analytical Methods for Secondary Metabolite Detection.

    PubMed

    Taibon, Judith; Strasser, Hermann

    2016-01-01

    The entomopathogenic fungi Metarhizium brunneum, Beauveria bassiana, and B. brongniartii are widely applied as biological pest control agent in OECD countries. Consequently, their use has to be flanked by a risk management approach, which includes the need to monitor the fate of their relevant toxic metabolites. There are still data gaps claimed by regulatory authorities pending on their identification and quantification of relevant toxins or secondary metabolites. In this chapter, analytical methods are presented allowing the qualitative and quantitative analysis of the relevant toxic B. brongniartii metabolite oosporein and the three M. brunneum relevant destruxin (dtx) derivatives dtx A, dtx B, and dtx E.

  2. The greening of PCB analytical methods

    SciTech Connect

    Erickson, M.D.; Alvarado, J.S.; Aldstadt, J.H.

    1995-12-01

    Green chemistry incorporates waste minimization, pollution prevention and solvent substitution. The primary focus of green chemistry over the past decade has been within the chemical industry; adoption by routine environmental laboratories has been slow because regulatory standard methods must be followed. A related paradigm, microscale chemistry has gained acceptance in undergraduate teaching laboratories, but has not been broadly applied to routine environmental analytical chemistry. We are developing green and microscale techniques for routine polychlorinated biphenyl (PCB) analyses as an example of the overall potential within the environmental analytical community. Initial work has focused on adaptation of commonly used routine EPA methods for soils and oils. Results of our method development and validation demonstrate that: (1) Solvent substitution can achieve comparable results and eliminate environmentally less-desirable solvents, (2) Microscale extractions can cut the scale of the analysis by at least a factor of ten, (3) We can better match the amount of sample used with the amount needed for the GC determination step, (4) The volume of waste generated can be cut by at least a factor of ten, and (5) Costs are reduced significantly in apparatus, reagent consumption, and labor.

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

    PubMed

    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.

  4. Advances in analytical technologies for environmental protection and public safety.

    PubMed

    Sadik, O A; Wanekaya, A K; Andreescu, S

    2004-06-01

    Due to the increased threats of chemical and biological agents of injury by terrorist organizations, a significant effort is underway to develop tools that can be used to detect and effectively combat chemical and biochemical toxins. In addition to the right mix of policies and training of medical personnel on how to recognize symptoms of biochemical warfare agents, the major success in combating terrorism still lies in the prevention, early detection and the efficient and timely response using reliable analytical technologies and powerful therapies for minimizing the effects in the event of an attack. The public and regulatory agencies expect reliable methodologies and devices for public security. Today's systems are too bulky or slow to meet the "detect-to-warn" needs for first responders such as soldiers and medical personnel. This paper presents the challenges in monitoring technologies for warfare agents and other toxins. It provides an overview of how advances in environmental analytical methodologies could be adapted to design reliable sensors for public safety and environmental surveillance. The paths to designing sensors that meet the needs of today's measurement challenges are analyzed using examples of novel sensors, autonomous cell-based toxicity monitoring, 'Lab-on-a-Chip' devices and conventional environmental analytical techniques. Finally, in order to ensure that the public and legal authorities are provided with quality data to make informed decisions, guidelines are provided for assessing data quality and quality assurance using the United States Environmental Protection Agency (US-EPA) methodologies. PMID:15173903

  5. Advanced methods of structural and trajectory analysis for transport aircraft

    NASA Technical Reports Server (NTRS)

    Ardema, Mark D.

    1995-01-01

    This report summarizes the efforts in two areas: (1) development of advanced methods of structural weight estimation, and (2) development of advanced methods of trajectory optimization. The majority of the effort was spent in the structural weight area. A draft of 'Analytical Fuselage and Wing Weight Estimation of Transport Aircraft', resulting from this research, is included as an appendix.

  6. Numerical methods: Analytical benchmarking in transport theory

    SciTech Connect

    Ganapol, B.D. )

    1988-01-01

    Numerical methods applied to reactor technology have reached a high degree of maturity. Certainly one- and two-dimensional neutron transport calculations have become routine, with several programs available on personal computer and the most widely used programs adapted to workstation and minicomputer computational environments. With the introduction of massive parallelism and as experience with multitasking increases, even more improvement in the development of transport algorithms can be expected. Benchmarking an algorithm is usually not a very pleasant experience for the code developer. Proper algorithmic verification by benchmarking involves the following considerations: (1) conservation of particles, (2) confirmation of intuitive physical behavior, and (3) reproduction of analytical benchmark results. By using today's computational advantages, new basic numerical methods have been developed that allow a wider class of benchmark problems to be considered.

  7. Insights from advanced analytics at the Veterans Health Administration.

    PubMed

    Fihn, Stephan D; Francis, Joseph; Clancy, Carolyn; Nielson, Christopher; Nelson, Karin; Rumsfeld, John; Cullen, Theresa; Bates, Jack; Graham, Gail L

    2014-07-01

    Health care has lagged behind other industries in its use of advanced analytics. The Veterans Health Administration (VHA) has three decades of experience collecting data about the veterans it serves nationwide through locally developed information systems that use a common electronic health record. In 2006 the VHA began to build its Corporate Data Warehouse, a repository for patient-level data aggregated from across the VHA's national health system. This article provides a high-level overview of the VHA's evolution toward "big data," defined as the rapid evolution of applying advanced tools and approaches to large, complex, and rapidly changing data sets. It illustrates how advanced analysis is already supporting the VHA's activities, which range from routine clinical care of individual patients--for example, monitoring medication administration and predicting risk of adverse outcomes--to evaluating a systemwide initiative to bring the principles of the patient-centered medical home to all veterans. The article also shares some of the challenges, concerns, insights, and responses that have emerged along the way, such as the need to smoothly integrate new functions into clinical workflow. While the VHA is unique in many ways, its experience may offer important insights for other health care systems nationwide as they venture into the realm of big data. PMID:25006147

  8. Insights from advanced analytics at the Veterans Health Administration.

    PubMed

    Fihn, Stephan D; Francis, Joseph; Clancy, Carolyn; Nielson, Christopher; Nelson, Karin; Rumsfeld, John; Cullen, Theresa; Bates, Jack; Graham, Gail L

    2014-07-01

    Health care has lagged behind other industries in its use of advanced analytics. The Veterans Health Administration (VHA) has three decades of experience collecting data about the veterans it serves nationwide through locally developed information systems that use a common electronic health record. In 2006 the VHA began to build its Corporate Data Warehouse, a repository for patient-level data aggregated from across the VHA's national health system. This article provides a high-level overview of the VHA's evolution toward "big data," defined as the rapid evolution of applying advanced tools and approaches to large, complex, and rapidly changing data sets. It illustrates how advanced analysis is already supporting the VHA's activities, which range from routine clinical care of individual patients--for example, monitoring medication administration and predicting risk of adverse outcomes--to evaluating a systemwide initiative to bring the principles of the patient-centered medical home to all veterans. The article also shares some of the challenges, concerns, insights, and responses that have emerged along the way, such as the need to smoothly integrate new functions into clinical workflow. While the VHA is unique in many ways, its experience may offer important insights for other health care systems nationwide as they venture into the realm of big data.

  9. Analytical methods for human biomonitoring of pesticides. A review.

    PubMed

    Yusa, Vicent; Millet, Maurice; Coscolla, Clara; Roca, Marta

    2015-09-01

    Biomonitoring of both currently-used and banned-persistent pesticides is a very useful tool for assessing human exposure to these chemicals. In this review, we present current approaches and recent advances in the analytical methods for determining the biomarkers of exposure to pesticides in the most commonly used specimens, such as blood, urine, and breast milk, and in emerging non-invasive matrices such as hair and meconium. We critically discuss the main applications for sample treatment, and the instrumental techniques currently used to determine the most relevant pesticide biomarkers. We finally look at the future trends in this field.

  10. Analytic Method for Computing Instrument Pointing Jitter

    NASA Technical Reports Server (NTRS)

    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.

  11. Analytical methods for optical remote sensing

    SciTech Connect

    Spellicy, R.L.

    1997-12-31

    Optical monitoring systems are very powerful because of their ability to see many compounds simultaneously as well as their ability to report results in real time. However, these strengths also present unique problems to analysis of the resulting data and validation of observed results. Today, many FTIR and UV-DOAS systems are in use. Some of these are manned systems supporting short term tests while others are totally unmanned systems which are expected to operate without intervention for weeks or months at a time. The analytical methods needed to support both the diversity of compounds and the diversity of applications is challenging. In this paper, the fundamental concepts of spectral analysis for IR/UV systems are presented. This is followed by examples of specific field data from both short term measurement programs looking at unique sources and long-term unmanned monitoring systems looking at ambient air.

  12. Advanced analytical electron microscopy for alkali-ion batteries

    DOE PAGES

    Qian, Danna; Ma, Cheng; Meng, Ying Shirley; More, Karren; Chi, Miaofang

    2015-01-01

    Lithium-ion batteries are a leading candidate for electric vehicle and smart grid applications. However, further optimizations of the energy/power density, coulombic efficiency and cycle life are still needed, and this requires a thorough understanding of the dynamic evolution of each component and their synergistic behaviors during battery operation. With the capability of resolving the structure and chemistry at an atomic resolution, advanced analytical transmission electron microscopy (AEM) is an ideal technique for this task. The present review paper focuses on recent contributions of this important technique to the fundamental understanding of the electrochemical processes of battery materials. A detailed reviewmore » of both static (ex situ) and real-time (in situ) studies will be given, and issues that still need to be addressed will be discussed.« less

  13. Advanced analytical electron microscopy for alkali-ion batteries

    SciTech Connect

    Qian, Danna; Ma, Cheng; Meng, Ying Shirley; More, Karren; Chi, Miaofang

    2015-01-01

    Lithium-ion batteries are a leading candidate for electric vehicle and smart grid applications. However, further optimizations of the energy/power density, coulombic efficiency and cycle life are still needed, and this requires a thorough understanding of the dynamic evolution of each component and their synergistic behaviors during battery operation. With the capability of resolving the structure and chemistry at an atomic resolution, advanced analytical transmission electron microscopy (AEM) is an ideal technique for this task. The present review paper focuses on recent contributions of this important technique to the fundamental understanding of the electrochemical processes of battery materials. A detailed review of both static (ex situ) and real-time (in situ) studies will be given, and issues that still need to be addressed will be discussed.

  14. Pyrroloquinoline quinone: Metabolism and analytical methods

    SciTech Connect

    Smidt, C.R.

    1990-01-01

    Pyrroloquinoline quinone (PQQ) functions as a cofactor for bacterial oxidoreductases. Whether or not PQQ serves as a cofactor in higher plants and animals remains controversial. Nevertheless, strong evidence exists that PQQ has nutritional importance. In highly purified, chemically defined diets PQQ stimulates animal growth. Further PQQ deprivation impairs connective tissue maturation, particularly when initiated in utero and throughout perinatal development. The study addresses two main objectives: (1) to elucidate basic aspects of the metabolism of PQQ in animals, and (2) to develop and improve existing analytical methods for PQQ. To study intestinal absorption of PQQ, ten mice were administered [[sup 14]C]-PQQ per os. PQQ was readily absorbed (62%) in the lower intestine and was excreted by the kidney within 24 hours. Significant amounts of labeled-PQQ were retained only by skin and kidney. Three approaches were taken to answer the question whether or not PQQ is synthesized by the intestinal microflora of mice. First, dietary antibiotics had no effect on fecal PQQ excretion. Then, no bacterial isolates could be identified that are known to synthesize PQQ. Last, cecal contents were incubated anaerobically with radiolabeled PQQ-precursors with no label appearing in isolated PQQ. Thus, intestinal PQQ synthesis is unlikely. Analysis of PQQ in biological samples is problematic since PQQ forms adducts with nucleophilic compounds and binds to the protein fraction. Existing analytical methods are reviewed and a new approach is introduced that allows for detection of PQQ in animal tissue and foods. PQQ is freed from proteins by ion exchange chromatography, purified on activated silica cartridges, detected by a colorimetric redox-cycling assay, and identified by mass spectrometry. That compounds with the properties of PQQ may be nutritionally important offers interesting areas for future investigation.

  15. Analytical Failure Prediction Method Developed for Woven and Braided Composites

    NASA Technical Reports Server (NTRS)

    Min, James B.

    2003-01-01

    Historically, advances in aerospace engine performance and durability have been linked to improvements in materials. Recent developments in ceramic matrix composites (CMCs) have led to increased interest in CMCs to achieve revolutionary gains in engine performance. The use of CMCs promises many advantages for advanced turbomachinery engine development and may be especially beneficial for aerospace engines. The most beneficial aspects of CMC material may be its ability to maintain its strength to over 2500 F, its internal material damping, and its relatively low density. Ceramic matrix composites reinforced with two-dimensional woven and braided fabric preforms are being considered for NASA s next-generation reusable rocket turbomachinery applications (for example, see the preceding figure). However, the architecture of a textile composite is complex, and therefore, the parameters controlling its strength properties are numerous. This necessitates the development of engineering approaches that combine analytical methods with limited testing to provide effective, validated design analyses for the textile composite structures development.

  16. 40 CFR 161.180 - Enforcement analytical method.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Enforcement analytical method. 161.180... DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Product Chemistry Data Requirements § 161.180 Enforcement analytical method. An analytical method suitable for enforcement purposes must...

  17. 7 CFR 98.4 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... MEALS, READY-TO-EAT (MRE's), MEATS, AND MEAT PRODUCTS MRE's, Meats, and Related Meat Food Products § 98.... Army Individual Protection Directorate's Military Specifications, approved analytical test...

  18. Review of recent advances in analytical techniques for the determination of neurotransmitters

    PubMed Central

    Perry, Maura; Li, Qiang; Kennedy, Robert T.

    2009-01-01

    Methods and advances for monitoring neurotransmitters in vivo or for tissue analysis of neurotransmitters over the last five years are reviewed. The review is organized primarily by neurotransmitter type. Transmitter and related compounds may be monitored by either in vivo sampling coupled to analytical methods or implanted sensors. Sampling is primarily performed using microdialysis, but low-flow push-pull perfusion may offer advantages of spatial resolution while minimizing the tissue disruption associated with higher flow rates. Analytical techniques coupled to these sampling methods include liquid chromatography, capillary electrophoresis, enzyme assays, sensors, and mass spectrometry. Methods for the detection of amino acid, monoamine, neuropeptide, acetylcholine, nucleoside, and soluable gas neurotransmitters have been developed and improved upon. Advances in the speed and sensitivity of these methods have enabled improvements in temporal resolution and increased the number of compounds detectable. Similar advances have enabled improved detection at tissue samples, with a substantial emphasis on single cell and other small samples. Sensors provide excellent temporal and spatial resolution for in vivo monitoring. Advances in application to catecholamines, indoleamines, and amino acids have been prominent. Improvements in stability, sensitivity, and selectivity of the sensors have been of paramount interest. PMID:19800472

  19. [Pharmacokinetics, metabolism, and analytical methods of ethanol].

    PubMed

    Goullé, J-P; Guerbet, M

    2015-09-01

    Alcohol is a licit substance whose significant consumption is responsible for a major public health problem. Every year, a large number of deaths are related to its consumption. It is also involved in various accidents, on the road, at work, as well as during acts of violence. Ethanol absorption and its fate are detailed. It is mainly absorbed in the small intestine. It accompanies the movements of the water, so it diffuses in all the tissues uniformly with the exception of bones and fat. The major route of ethanol detoxification is located into the liver. Detoxification is a saturable two-step oxidation. During the first stage ethanol is oxidized into acetaldehyde, under the action of alcohol dehydrogenase. During the second stage acetaldehyde is oxidized into acetate. Genetic factors or some drugs are able to disturb the absorption and the metabolism of ethanol. The analytical methods for the quantification of alcohol in man include analysis in exhaled air and in blood. The screening and quantification of ethanol for road safety are performed in exhaled air. In hospitals, blood ethanol determination is routinely performed by enzymatic method, but the rule for forensic samples is gas chromatography.

  20. The role of big data and advanced analytics in drug discovery, development, and commercialization.

    PubMed

    Szlezák, N; Evers, M; Wang, J; Pérez, L

    2014-05-01

    In recent years, few ideas have captured the imagination of health-care practitioners as much as the advent of "big data" and the advanced analytical methods and technologies used to interpret it-it is a trend seen as having the potential to revolutionize biology, medicine, and health care.(1,2,3) As new types of data and tools become available, a unique opportunity is emerging for smarter and more effective discovery, development, and commercialization of innovative biopharmaceutical drugs.

  1. Advances in Assays and Analytical Approaches for Botulinum Toxin Detection

    SciTech Connect

    Grate, Jay W.; Ozanich, Richard M.; Warner, Marvin G.; Bruckner-Lea, Cindy J.; Marks, James D.

    2010-08-04

    Methods to detect botulinum toxin, the most poisonous substance known, are reviewed. Current assays are being developed with two main objectives in mind: 1) to obtain sufficiently low detection limits to replace the mouse bioassay with an in vitro assay, and 2) to develop rapid assays for screening purposes that are as sensitive as possible while requiring an hour or less to process the sample an obtain the result. This review emphasizes the diverse analytical approaches and devices that have been developed over the last decade, while also briefly reviewing representative older immunoassays to provide background and context.

  2. 40 CFR 425.03 - Sulfide analytical methods and applicability.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Provisions § 425.03 Sulfide analytical methods and applicability. (a) The potassium ferricyanide titration... the potassium ferricyanide titration method for the determination of sulfide in wastewaters...

  3. 40 CFR 425.03 - Sulfide analytical methods and applicability.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Provisions § 425.03 Sulfide analytical methods and applicability. (a) The potassium ferricyanide titration... the potassium ferricyanide titration method for the determination of sulfide in wastewaters...

  4. 40 CFR 425.03 - Sulfide analytical methods and applicability.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Provisions § 425.03 Sulfide analytical methods and applicability. (a) The potassium ferricyanide titration... the potassium ferricyanide titration method for the determination of sulfide in wastewaters...

  5. Green analytical method development for statin analysis.

    PubMed

    Assassi, Amira Louiza; Roy, Claude-Eric; Perovitch, Philippe; Auzerie, Jack; Hamon, Tiphaine; Gaudin, Karen

    2015-02-01

    Green analytical chemistry method was developed for pravastatin, fluvastatin and atorvastatin analysis. HPLC/DAD method using ethanol-based mobile phase with octadecyl-grafted silica with various grafting and related-column parameters such as particle sizes, core-shell and monolith was studied. Retention, efficiency and detector linearity were optimized. Even for column with particle size under 2 μm, the benefit of keeping efficiency within a large range of flow rate was not obtained with ethanol based mobile phase compared to acetonitrile one. Therefore the strategy to shorten analysis by increasing the flow rate induced decrease of efficiency with ethanol based mobile phase. An ODS-AQ YMC column, 50 mm × 4.6 mm, 3 μm was selected which showed the best compromise between analysis time, statin separation, and efficiency. HPLC conditions were at 1 mL/min, ethanol/formic acid (pH 2.5, 25 mM) (50:50, v/v) and thermostated at 40°C. To reduce solvent consumption for sample preparation, 0.5mg/mL concentration of each statin was found the highest which respected detector linearity. These conditions were validated for each statin for content determination in high concentrated hydro-alcoholic solutions. Solubility higher than 100mg/mL was found for pravastatin and fluvastatin, whereas for atorvastatin calcium salt the maximum concentration was 2mg/mL for hydro-alcoholic binary mixtures between 35% and 55% of ethanol in water. Using atorvastatin instead of its calcium salt, solubility was improved. Highly concentrated solution of statins offered potential fluid for per Buccal Per-Mucous(®) administration with the advantages of rapid and easy passage of drugs. PMID:25582487

  6. 40 CFR 136.6 - Method modifications and analytical requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... person or laboratory using a test procedure (analytical method) in this Part. (2) Chemistry of the method... (analytical method) provided that the chemistry of the method or the determinative technique is not changed... prevent efficient recovery of organic pollutants and prevent the method from meeting QC requirements,...

  7. Experimental and analytical studies of advanced air cushion landing systems

    NASA Technical Reports Server (NTRS)

    Lee, E. G. S.; Boghani, A. B.; Captain, K. M.; Rutishauser, H. J.; Farley, H. L.; Fish, R. B.; Jeffcoat, R. L.

    1981-01-01

    Several concepts are developed for air cushion landing systems (ACLS) which have the potential for improving performance characteristics (roll stiffness, heave damping, and trunk flutter), and reducing fabrication cost and complexity. After an initial screening, the following five concepts were evaluated in detail: damped trunk, filled trunk, compartmented trunk, segmented trunk, and roll feedback control. The evaluation was based on tests performed on scale models. An ACLS dynamic simulation developed earlier is updated so that it can be used to predict the performance of full-scale ACLS incorporating these refinements. The simulation was validated through scale-model tests. A full-scale ACLS based on the segmented trunk concept was fabricated and installed on the NASA ACLS test vehicle, where it is used to support advanced system development. A geometrically-scaled model (one third full scale) of the NASA test vehicle was fabricated and tested. This model, evaluated by means of a series of static and dynamic tests, is used to investigate scaling relationships between reduced and full-scale models. The analytical model developed earlier is applied to simulate both the one third scale and the full scale response.

  8. Advanced analytical facilities report of the planetary materials and geochemistry working group

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The role of advanced analytical facilities; upgrading/replacement of the existing facilities; the relationship of advanced facilities to the present program; and possible facilities are examined. Major conclusions and recommendations are presented.

  9. Metalaxyl: persistence, degradation, metabolism, and analytical methods.

    PubMed

    Sukul, P; Spiteller, M

    2000-01-01

    Metalaxyl is a systemic fungicide used to control plant diseases caused by Oomycete fungi. Its formulations include granules, wettable powders, dusts, and emulsifiable concentrates. Application may be by foliar or soil incorporation, surface spraying (broadcast or band), drenching, and seed treatment. Metalaxyl registered products either contain metalaxyl as the sole active ingredient or are combined with other active ingredients (e.g., captan, mancozeb, copper compounds, carboxin). Due to its broad-spectrum activity, metalaxyl is used world-wide on a variety of fruit and vegetable crops. Its effectiveness results from inhibition of uridine incorporation into RNA and specific inhibition of RNA polymerase-1. Metalaxyl has both curative and systemic properties. Its mammalian toxicity is classified as EPA toxicity class III and it is also relatively non-toxic to most nontarget arthropod and vertebrate species. Adequate analytical methods of TLC, GLC, HPLC, MS, and other techniques are available for identification and determination of metalaxyl residues and its metabolites. Available laboratory and field studies indicate that metalaxyl is stable to hydrolysis under normal environmental pH values, It is also photolytically stable in water and soil when exposed to natural sunlight. Its tolerance to a wide range of pH, light, and temperature leads to its continued use in agriculture. Metalaxyl is photodecomposed in UV light, and photoproducts are formed by rearrangement of the N-acyl group to the aromatic ring, demethoxylation, N-deacylation, and elimination of the methoxycarbonyl group from the molecule. Photosensitizers such as humic acid, TiO2, H2O2, acetone, and riboflavin accelerate its photodecomposition. Information is provided on the fate of metalaxyl in plant, soil, water, and animals. Major metabolic routes include hydrolysis of the methyl ester and methyl ether oxidation of the ring-methyl groups. The latter are precursors of conjugates in plants and animals

  10. The evolution of analytical chemistry methods in foodomics.

    PubMed

    Gallo, Monica; Ferranti, Pasquale

    2016-01-01

    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. PMID:26363946

  11. The evolution of analytical chemistry methods in foodomics.

    PubMed

    Gallo, Monica; Ferranti, Pasquale

    2016-01-01

    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.

  12. 40 CFR 425.03 - Sulfide analytical methods and applicability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... § 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...

  13. 40 CFR 425.03 - Sulfide analytical methods and applicability.

    Code of Federal Regulations, 2010 CFR

    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...

  14. 40 CFR 158.355 - Enforcement analytical method.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Enforcement analytical method. 158.355 Section 158.355 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.355 Enforcement analytical method....

  15. 40 CFR 158.355 - Enforcement analytical method.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Enforcement analytical method. 158.355 Section 158.355 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.355 Enforcement analytical method....

  16. 40 CFR 158.355 - Enforcement analytical method.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Enforcement analytical method. 158.355 Section 158.355 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.355 Enforcement analytical method....

  17. 40 CFR 158.355 - Enforcement analytical method.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Enforcement analytical method. 158.355 Section 158.355 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.355 Enforcement analytical method....

  18. 40 CFR 158.355 - Enforcement analytical method.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Enforcement analytical method. 158.355 Section 158.355 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR PESTICIDES Product Chemistry § 158.355 Enforcement analytical method....

  19. Analytic Nonlinear Methods for Beam Optics

    SciTech Connect

    Irwin, John; /SLAC

    2011-08-31

    In recent years there have been major advances in the computation and use of high-order maps for the design, optimization and operation of beamlines. We will describe five practical examples for both linear and circular colliders. From least to most complex these examples will be: use of similarity transformations (FFTB design, SLC diagnosis); statistical maps (SSC smear and tune-shift); aberrations (SLC upgrade); resonance basis and nPB tracking (PEP-II design); and kick factorization (possibly LHC).

  20. Electroextraction and electromembrane extraction: Advances in hyphenation to analytical techniques

    PubMed Central

    Oedit, Amar; Ramautar, Rawi; Hankemeier, Thomas

    2016-01-01

    Electroextraction (EE) and electromembrane extraction (EME) are sample preparation techniques that both require an electric field that is applied over a liquid‐liquid system, which enables the migration of charged analytes. Furthermore, both techniques are often used to pre‐concentrate analytes prior to analysis. In this review an overview is provided of the body of literature spanning April 2012–November 2015 concerning EE and EME, focused on hyphenation to analytical techniques. First, the theoretical aspects of concentration enhancement in EE and EME are discussed to explain extraction recovery and enrichment factor. Next, overviews are provided of the techniques based on their hyphenation to LC, GC, CE, and direct detection. These overviews cover the compounds and matrices, experimental aspects (i.e. donor volume, acceptor volume, extraction time, extraction voltage, and separation time) and the analytical aspects (i.e. limit of detection, enrichment factor, and extraction recovery). Techniques that were either hyphenated online to analytical techniques or show high potential with respect to online hyphenation are highlighted. Finally, the potential future directions of EE and EME are discussed. PMID:26864699

  1. Thiram: degradation, applications and analytical methods.

    PubMed

    Sharma, Vaneet Kumar; Aulakh, J S; Malik, Ashok Kumar

    2003-10-01

    In this review a brief introduction to thiram (tetramethylthiuram disulfide; TMTD) pesticide has been given along with other applications. All the important methods available are systematically arranged and are listed under various techniques. Some of these methods have been applied for the determination of thiram in commercial formulations, synthetic mixtures in grains, vegetables and fruits. A comparison of different methods is the salient feature of this review.

  2. Learner Language Analytic Methods and Pedagogical Implications

    ERIC Educational Resources Information Center

    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…

  3. Fast Analytical Methods for Macroscopic Electrostatic Models in Biomolecular Simulations*

    PubMed Central

    Xu, Zhenli; Cai, Wei

    2013-01-01

    We review recent developments of fast analytical methods for macroscopic electrostatic calculations in biological applications, including the Poisson–Boltzmann (PB) and the generalized Born models for electrostatic solvation energy. The focus is on analytical approaches for hybrid solvation models, especially the image charge method for a spherical cavity, and also the generalized Born theory as an approximation to the PB model. This review places much emphasis on the mathematical details behind these methods. PMID:23745011

  4. 7 CFR 98.4 - Analytical methods.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... MEALS, READY-TO-EAT (MRE's), MEATS, AND MEAT PRODUCTS MRE's, Meats, and Related Meat Food Products § 98... perform analyses of meat, meat food products and MRE's are listed as follows: (1) Official Methods...

  5. 7 CFR 98.4 - Analytical methods.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... MEALS, READY-TO-EAT (MREs), MEATS, AND MEAT PRODUCTS MREs, Meats, and Related Meat Food Products § 98.4... of meat, meat food products and MREs are listed as follows: (1) Official Methods of Analysis of...

  6. 7 CFR 98.4 - Analytical methods.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... MEALS, READY-TO-EAT (MRE's), MEATS, AND MEAT PRODUCTS MRE's, Meats, and Related Meat Food Products § 98... perform analyses of meat, meat food products and MRE's are listed as follows: (1) Official Methods...

  7. 7 CFR 98.4 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... MEALS, READY-TO-EAT (MRE's), MEATS, AND MEAT PRODUCTS MRE's, Meats, and Related Meat Food Products § 98... perform analyses of meat, meat food products and MRE's are listed as follows: (1) Official Methods...

  8. 7 CFR 91.23 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... are used. The manuals of standard methods most often used by the Science and Technology laboratories... Practices of the American Oil Chemists' Society (AOCS), American Oil Chemists' Society, P.O. Box 3489,...

  9. 7 CFR 91.23 - Analytical methods.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... are used. The manuals of standard methods most often used by the Science and Technology laboratories... Practices of the American Oil Chemists' Society (AOCS), American Oil Chemists' Society, P.O. Box 3489,...

  10. 7 CFR 91.23 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Examination of Foods, Carl Vanderzant and Don Splittstoesser (Editors), American Public Health Association.... Environmental Protection Agency (EPA) Chemical Exposure Research Branch, EPA Office of Research and Development... Methods for the Examination of Dairy Products, American Public Health Association, 1015 Fifteenth...

  11. Advanced Fine Particulate Characterization Methods

    SciTech Connect

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  12. 40 CFR 141.704 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR.... (b) E. coli. System must use methods for enumeration of E. coli in source water approved in § 136.3(a... of an E. coli sample for up to 48 hours between sample collection and initiation of analysis if...

  13. 40 CFR 141.704 - Analytical methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR.... (b) E. coli. System must use methods for enumeration of E. coli in source water approved in § 136.3(a... of an E. coli sample for up to 48 hours between sample collection and initiation of analysis if...

  14. 40 CFR 141.704 - Analytical methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR.... (b) E. coli. System must use methods for enumeration of E. coli in source water approved in § 136.3(a... of an E. coli sample for up to 48 hours between sample collection and initiation of analysis if...

  15. 40 CFR 141.704 - Analytical methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR.... (b) E. coli. System must use methods for enumeration of E. coli in source water approved in § 136.3(a... of an E. coli sample for up to 48 hours between sample collection and initiation of analysis if...

  16. 40 CFR 141.704 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR.... (b) E. coli. System must use methods for enumeration of E. coli in source water approved in § 136.3(a... of an E. coli sample for up to 48 hours between sample collection and initiation of analysis if...

  17. 7 CFR 94.4 - Analytical methods.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... follows: (a) Compendium Methods for the Microbiological Examination of Foods, Carl Vanderzant and Don Splittstoesser (Editors), American Public Health Association, 1015 Fifteenth Street, NW, Washington, DC 20005. (b... Examination of Dairy Products, American Public Health Association, 1015 Fifteenth Street, NW, Washington,...

  18. 7 CFR 94.4 - Analytical methods.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... follows: (a) Compendium Methods for the Microbiological Examination of Foods, Carl Vanderzant and Don Splittstoesser (Editors), American Public Health Association, 1015 Fifteenth Street, NW, Washington, DC 20005. (b... Examination of Dairy Products, American Public Health Association, 1015 Fifteenth Street, NW, Washington,...

  19. 7 CFR 94.4 - Analytical methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... follows: (a) Compendium Methods for the Microbiological Examination of Foods, Carl Vanderzant and Don Splittstoesser (Editors), American Public Health Association, 1015 Fifteenth Street, NW, Washington, DC 20005. (b... Examination of Dairy Products, American Public Health Association, 1015 Fifteenth Street, NW, Washington,...

  20. 7 CFR 94.4 - Analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...), Volumes I and II, Food and Drug Administration, Center for Food Safety and Applied Nutrition (CFSAN), 200... follows: (a) Compendium Methods for the Microbiological Examination of Foods, Carl Vanderzant and Don Splittstoesser (Editors), American Public Health Association, 1015 Fifteenth Street, NW, Washington, DC 20005....

  1. Advanced diagnostic methods in avionics

    NASA Astrophysics Data System (ADS)

    Popyack, Leonard Joseph, Jr.

    Advanced diagnostic systems facilitate further enhancement of reliability and safety of modern aircraft. Unlike classical reliability analyses, addressing specific classes of systems or devices, this research is aimed at the development of methods for assessment of the individual reliability characteristics of particular system components subjected to their unique histories of operational conditions and exposure to adverse environmental factors. Individual reliability characteristics are crucial for the implementation of the most efficient maintenance practice of flight-critical system components, known as "condition-based maintenance." The dissertation presents hardware and software aspects of a computer-based system, Time-Stress Monitoring Device, developed to record, store, and analyze raw data characterizing operational and environmental conditions and performance of electro-mechanical flight control system components and aircraft electronics (avionics). Availability of this data facilitates formulation and solution of such diagnostic problems as estimation of the probability of failure and life expectancy of particular components, failure detection, identification, and prediction. Statistical aspects of system diagnostics are considered. Particular diagnostic procedures utilizing cluster analysis, Bayes' technique, and regression analysis are formulated. Laboratory and simulation experiment that verify the obtained results are provided.

  2. FIELD ANALYTICAL SCREENING PROGRAM: PCB METHOD - INNOVATIVE TECHNOLOGY REPORT

    EPA Science Inventory

    This innovative technology evaluation report (ITER) presents information on the demonstration of the U.S. Environmental Protection Agency (EPA) Region 7 Superfund Field Analytical Screening Program (FASP) method for determining polychlorinated biphenyl (PCB) contamination in soil...

  3. Methods for Estimating Uncertainty in Factor Analytic Solutions

    EPA Science Inventory

    The EPA PMF (Environmental Protection Agency positive matrix factorization) version 5.0 and the underlying multilinear engine-executable ME-2 contain three methods for estimating uncertainty in factor analytic models: classical bootstrap (BS), displacement of factor elements (DI...

  4. Analytical chemistry methods for mixed oxide fuel, March 1985

    SciTech Connect

    Not Available

    1985-03-01

    This standard provides analytical chemistry methods for the analysis of materials used to produce mixed oxide fuel. These materials are ceramic fuel and insulator pellets and the plutonium and uranium oxides and nitrates used to fabricate these pellets.

  5. 40 CFR 136.6 - Method modifications and analytical requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... person or laboratory using a test procedure (analytical method) in this part. (2) Chemistry of the method... oxygen demand. (6) QC means “quality control.” (b) Method modifications. (1) If the underlying chemistry... notification should be of the form “Method xxx has been modified within the flexibility allowed in 40 CFR...

  6. 40 CFR 136.6 - Method modifications and analytical requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... person or laboratory using a test procedure (analytical method) in this part. (2) Chemistry of the method... oxygen demand. (6) QC means “quality control.” (b) Method modifications. (1) If the underlying chemistry... notification should be of the form “Method xxx has been modified within the flexibility allowed in 40 CFR...

  7. 40 CFR 136.6 - Method modifications and analytical requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... person or laboratory using a test procedure (analytical method) in this part. (2) Chemistry of the method... oxygen demand. (6) QC means “quality control.” (b) Method modifications. (1) If the underlying chemistry... notification should be of the form “Method xxx has been modified within the flexibility allowed in 40 CFR...

  8. 40 CFR 766.16 - Developing the analytical test method.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... analytical test method. Because of the matrix differences of the chemicals listed for testing, no one method... to separate the HDDs/HDFs from the sample matrix. Methods are reviewed in the Guidelines under § 766... meet the requirements of the chemical matrix. (d) Analysis. The method of choice is High Resolution...

  9. Analytical techniques for instrument design - matrix methods

    SciTech Connect

    Robinson, R.A.

    1997-09-01

    We take the traditional Cooper-Nathans approach, as has been applied for many years for steady-state triple-axis spectrometers, and consider its generalisation to other inelastic scattering spectrometers. This involves a number of simple manipulations of exponentials of quadratic forms. In particular, we discuss a toolbox of matrix manipulations that can be performed on the 6- dimensional Cooper-Nathans matrix: diagonalisation (Moller-Nielsen method), coordinate changes e.g. from ({Delta}k{sub I},{Delta}k{sub F} to {Delta}E, {Delta}Q & 2 dummy variables), integration of one or more variables (e.g. over such dummy variables), integration subject to linear constraints (e.g. Bragg`s Law for analysers), inversion to give the variance-covariance matrix, and so on. We show how these tools can be combined to solve a number of important problems, within the narrow-band limit and the gaussian approximation. We will argue that a generalised program that can handle multiple different spectrometers could (and should) be written in parallel to the Monte-Carlo packages that are becoming available. We will also discuss the complementarity between detailed Monte-Carlo calculations and the approach presented here. In particular, Monte-Carlo methods traditionally simulate the real experiment as performed in practice, given a model scattering law, while the Cooper-Nathans method asks the inverse question: given that a neutron turns up in a particular spectrometer configuration (e.g. angle and time of flight), what is the probability distribution of possible scattering events at the sample? The Monte-Carlo approach could be applied in the same spirit to this question.

  10. Handbook of Analytical Methods for Textile Composites

    NASA Technical Reports Server (NTRS)

    Cox, Brian N.; Flanagan, Gerry

    1997-01-01

    The purpose of this handbook is to introduce models and computer codes for predicting the properties of textile composites. The handbook includes several models for predicting the stress-strain response all the way to ultimate failure; methods for assessing work of fracture and notch sensitivity; and design rules for avoiding certain critical mechanisms of failure, such as delamination, by proper textile design. The following textiles received some treatment: 2D woven, braided, and knitted/stitched laminates and 3D interlock weaves, and braids.

  11. Analytical techniques for instrument design -- Matrix methods

    SciTech Connect

    Robinson, R.A.

    1997-12-31

    The authors take the traditional Cooper-Nathans approach, as has been applied for many years for steady-state triple-axis spectrometers, and consider its generalization to other inelastic scattering spectrometers. This involves a number of simple manipulations of exponentials of quadratic forms. In particular, they discuss a toolbox of matrix manipulations that can be performed on the 6-dimensional Cooper-Nathans matrix. They show how these tools can be combined to solve a number of important problems, within the narrow-band limit and the gaussian approximation. They will argue that a generalized program that can handle multiple different spectrometers could (and should) be written in parallel to the Monte-Carlo packages that are becoming available. They also discuss the complementarity between detailed Monte-Carlo calculations and the approach presented here. In particular, Monte-Carlo methods traditionally simulate the real experiment as performed in practice, given a model scattering law, while the Cooper-Nathans method asks the inverse question: given that a neutron turns up in a particular spectrometer configuration (e.g. angle and time of flight), what is the probability distribution of possible scattering events at the sample? The Monte-Carlo approach could be applied in the same spirit to this question.

  12. Relativistic mirrors in laser plasmas (analytical methods)

    NASA Astrophysics Data System (ADS)

    Bulanov, S. V.; Esirkepov, T. Zh; Kando, M.; Koga, J.

    2016-10-01

    Relativistic flying mirrors in plasmas are realized as thin dense electron (or electron-ion) layers accelerated by high-intensity electromagnetic waves to velocities close to the speed of light in vacuum. The reflection of an electromagnetic wave from the relativistic mirror results in its energy and frequency changing. In a counter-propagation configuration, the frequency of the reflected wave is multiplied by the factor proportional to the Lorentz factor squared. This scientific area promises the development of sources of ultrashort x-ray pulses in the attosecond range. The expected intensity will reach the level at which the effects predicted by nonlinear quantum electrodynamics start to play a key role. We present an overview of theoretical methods used to describe relativistic flying, accelerating, oscillating mirrors emerging in intense laser-plasma interactions.

  13. Fracture mechanics life analytical methods verification testing

    NASA Technical Reports Server (NTRS)

    Favenesi, J. A.; Clemons, T. G.; Riddell, W. T.; Ingraffea, A. R.; Wawrzynek, P. A.

    1994-01-01

    The objective was to evaluate NASCRAC (trademark) version 2.0, a second generation fracture analysis code, for verification and validity. NASCRAC was evaluated using a combination of comparisons to the literature, closed-form solutions, numerical analyses, and tests. Several limitations and minor errors were detected. Additionally, a number of major flaws were discovered. These major flaws were generally due to application of a specific method or theory, not due to programming logic. Results are presented for the following program capabilities: K versus a, J versus a, crack opening area, life calculation due to fatigue crack growth, tolerable crack size, proof test logic, tearing instability, creep crack growth, crack transitioning, crack retardation due to overloads, and elastic-plastic stress redistribution. It is concluded that the code is an acceptable fracture tool for K solutions of simplified geometries, for a limited number of J and crack opening area solutions, and for fatigue crack propagation with the Paris equation and constant amplitude loads when the Paris equation is applicable.

  14. Analytical instruments, ionization sources, and ionization methods

    DOEpatents

    Atkinson, David A.; Mottishaw, Paul

    2006-04-11

    Methods and apparatus for simultaneous vaporization and ionization of a sample in a spectrometer prior to introducing the sample into the drift tube of the analyzer are disclosed. The apparatus includes a vaporization/ionization source having an electrically conductive conduit configured to receive sample particulate which is conveyed to a discharge end of the conduit. Positioned proximate to the discharge end of the conduit is an electrically conductive reference device. The conduit and the reference device act as electrodes and have an electrical potential maintained between them sufficient to cause a corona effect, which will cause at least partial simultaneous ionization and vaporization of the sample particulate. The electrical potential can be maintained to establish a continuous corona, or can be held slightly below the breakdown potential such that arrival of particulate at the point of proximity of the electrodes disrupts the potential, causing arcing and the corona effect. The electrical potential can also be varied to cause periodic arcing between the electrodes such that particulate passing through the arc is simultaneously vaporized and ionized. The invention further includes a spectrometer containing the source. The invention is particularly useful for ion mobility spectrometers and atmospheric pressure ionization mass spectrometers.

  15. Recent advances in semi-analytical scattering models for NDT simulation

    NASA Astrophysics Data System (ADS)

    Darmon, M.; Chatillon, S.; Mahaut, S.; Calmon, P.; Fradkin, L. J.; Zernov, V.

    2011-01-01

    For several years, CEA-LIST and partners have been developing ultrasonic simulation tools with the aim of modelling non-destructive evaluation. The existing ultrasonic modules allow us to simulate fully real ultrasonic inspection scenarios in a range of applications which requires the computation of the propagated beam, as well as its interaction with flaws. To fulfil requirements of an intensive use (for parametric studies), the choice has been made to adopt mainly analytical approximate or exact methods to model the scattering of ultrasound by flaws. The applied analytical theories (Kirchhoff and Born approximations, GTD, SOV...) were already described in previous GDR communication. Over the years, this "semi-analytical" approach has been enriched by adaptations and improvements of the existing models or by new models, in order to extend the applicability of the simulation tools. This paper is devoted to the following recent advances performed in the framework of this approach: The SOV method based on the exact analytical model for the scattering from a cylindrical cavity has been extended in 3D to account for field variations along the cylinder. This new 3D model leads to an improvement in simulation of small side-drilled holes. Concerning the geometrical theories of diffraction (GTD), subroutines for calculation of the 2D wedge diffraction coefficients (for bulk or Rayleigh incident waves) have been developed by the Waves and Fields Group and uniform corrections (UAT and UTD) are under investigation. Modelling of the contribution of the head wave and creeping wave to the echoes arising from a wedge. Numerous experimental validations of the developed models are provided. New possibilities offered by these new developments are emphasized.

  16. Analytic Methods for Simulated Light Transport

    NASA Astrophysics Data System (ADS)

    Arvo, James Richard

    1995-01-01

    This thesis presents new mathematical and computational tools for the simulation of light transport in realistic image synthesis. New algorithms are presented for exact computation of direct illumination effects related to light emission, shadowing, and first-order scattering from surfaces. New theoretical results are presented for the analysis of global illumination algorithms, which account for all interreflections of light among surfaces of an environment. First, a closed-form expression is derived for the irradiance Jacobian, which is the derivative of a vector field representing radiant energy flux. The expression holds for diffuse polygonal scenes and correctly accounts for shadowing, or partial occlusion. Three applications of the irradiance Jacobian are demonstrated: locating local irradiance extrema, direct computation of isolux contours, and surface mesh generation. Next, the concept of irradiance is generalized to tensors of arbitrary order. A recurrence relation for irradiance tensors is derived that extends a widely used formula published by Lambert in 1760. Several formulas with applications in computer graphics are derived from this recurrence relation and are independently verified using a new Monte Carlo method for sampling spherical triangles. The formulas extend the range of non-diffuse effects that can be computed in closed form to include illumination from directional area light sources and reflections from and transmissions through glossy surfaces. Finally, new analysis for global illumination is presented, which includes both direct illumination and indirect illumination due to multiple interreflections of light. A novel operator equation is proposed that clarifies existing deterministic algorithms for simulating global illumination and facilitates error analysis. Basic properties of the operators and solutions are identified which are not evident from previous formulations. A taxonomy of errors that arise in simulating global illumination is

  17. Internal R and D task summary report: analytical methods development

    SciTech Connect

    Schweighardt, F.K.

    1983-07-01

    International Coal Refining Company (ICRC) conducted two research programs to develop analytical procedures for characterizing the feed, intermediates,and products of the proposed SRC-I Demonstration Plant. The major conclusion is that standard analytical methods must be defined and assigned statistical error limits of precision and reproducibility early in development. Comparing all SRC-I data or data from different processes is complex and expensive if common data correlation procedures are not followed. ICRC recommends that processes be audited analytically and statistical analyses generated as quickly as possible, in order to quantify process-dependent and -independent variables. 16 references, 10 figures, 20 tables.

  18. A Graph Analytic Metric for Mitigating Advanced Persistent Threat

    SciTech Connect

    Johnson, John R.; Hogan, Emilie A.

    2013-06-04

    This paper introduces a novel graph analytic metric that can be used to measure the potential vulnerability of a cyber network to specific types of attacks that use lateral movement and privilege escalation such as the well known Pass The Hash, (PTH). The metric is computed from an oriented subgraph of the underlying cyber network induced by selecting only those edges for which a given property holds between the two vertices of the edge. The metric with respect to a select node on the subgraph is defined as the likelihood that the select node is reachable from another arbitrary node in the graph. This metric can be calculated dynamically from the authorization and auditing layers during the network security authorization phase and will potentially enable predictive deterrence against attacks such as PTH.

  19. Statistically qualified neuro-analytic failure detection method and system

    DOEpatents

    Vilim, Richard B.; Garcia, Humberto E.; Chen, Frederick W.

    2002-03-02

    An apparatus and method for monitoring a process involve development and application of a statistically qualified neuro-analytic (SQNA) model to accurately and reliably identify process change. The development of the SQNA model is accomplished in two stages: deterministic model adaption and stochastic model modification of the deterministic model adaptation. Deterministic model adaption involves formulating an analytic model of the process representing known process characteristics, augmenting the analytic model with a neural network that captures unknown process characteristics, and training the resulting neuro-analytic model by adjusting the neural network weights according to a unique scaled equation error minimization technique. Stochastic model modification involves qualifying any remaining uncertainty in the trained neuro-analytic model by formulating a likelihood function, given an error propagation equation, for computing the probability that the neuro-analytic model generates measured process output. Preferably, the developed SQNA model is validated using known sequential probability ratio tests and applied to the process as an on-line monitoring system. Illustrative of the method and apparatus, the method is applied to a peristaltic pump system.

  20. Study of an analytical method for hexavalent chromium.

    PubMed

    Bhargava, O P; Bumsted, H E; Grunder, F I; Hunt, B L; Manning, G E; Riemann, R A; Samuels, J K; Tatone, V; Waldschmidt, S J; Hernandez, P

    1983-06-01

    The diphenylcarbazide colorimetric method was evaluated by analyzing spiked PVC filters prepared by an AIHA-accredited consultant laboratory for chromium (VI). All seven participating laboratories received the samples and performed the analyses at the same time. Three laboratories simultaneously tested three alternative analytical procedures. Reduced amounts of chromium (VI) were found by both the consultant and participating laboratories when using the test procedure and one of the alternative methods. Two of the alternative analytical methods, both of which involve an alkaline extraction procedure, provided higher recoveries and more precise values for the test filters. It appears that the alkaline extraction procedure may be more appropriate for occupational health samples taken in steel industry environments which may include several interferents. Suggestions are made for further studies to determine the most appropriate analytical method.

  1. Analytical methods for quantitation of prenylated flavonoids from hops.

    PubMed

    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

  2. Analytical methods for quantitation of prenylated flavonoids from hops

    PubMed Central

    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

  3. An advanced search engine for patent analytics in medicinal chemistry.

    PubMed

    Pasche, Emilie; Gobeill, Julien; Teodoro, Douglas; Gaudinat, Arnaud; Vishnykova, Dina; Lovis, Christian; Ruch, Patrick

    2012-01-01

    Patent collections contain an important amount of medical-related knowledge, but existing tools were reported to lack of useful functionalities. We present here the development of TWINC, an advanced search engine dedicated to patent retrieval in the domain of health and life sciences. Our tool embeds two search modes: an ad hoc search to retrieve relevant patents given a short query and a related patent search to retrieve similar patents given a patent. Both search modes rely on tuning experiments performed during several patent retrieval competitions. Moreover, TWINC is enhanced with interactive modules, such as chemical query expansion, which is of prior importance to cope with various ways of naming biomedical entities. While the related patent search showed promising performances, the ad-hoc search resulted in fairly contrasted results. Nonetheless, TWINC performed well during the Chemathlon task of the PatOlympics competition and experts appreciated its usability.

  4. Computer Subroutines for Analytic Rotation by Two Gradient Methods.

    ERIC Educational Resources Information Center

    van Thillo, Marielle

    Two computer subroutine packages for the analytic rotation of a factor matrix, A(p x m), are described. The first program uses the Flectcher (1970) gradient method, and the second uses the Polak-Ribiere (Polak, 1971) gradient method. The calculations in both programs involve the optimization of a function of free parameters. The result is a…

  5. An analytical method for designing low noise helicopter transmissions

    NASA Technical Reports Server (NTRS)

    Bossler, R. B., Jr.; Bowes, M. A.; Royal, A. C.

    1978-01-01

    The development and experimental validation of a method for analytically modeling the noise mechanism in the helicopter geared power transmission systems is described. This method can be used within the design process to predict interior noise levels and to investigate the noise reducing potential of alternative transmission design details. Examples are discussed.

  6. FIELD ANALYTICAL SCREENING PROGRAM: PCP METHOD - INNOVATIVE TECHNOLOGY EVALUATION REPORT

    EPA Science Inventory

    The Field Analytical Screening Program (FASP) pentachlorophenol (PCP) method uses a gas chromatograph (GC) equipped with a megabore capillary column and flame ionization detector (FID) and electron capture detector (ECD) to identify and quantify PCP. The FASP PCP method is design...

  7. Beamforming and holography image formation methods: an analytic study.

    PubMed

    Solimene, Raffaele; Cuccaro, Antonio; Ruvio, Giuseppe; Tapia, Daniel Flores; O'Halloran, Martin

    2016-04-18

    Beamforming and holographic imaging procedures are widely used in many applications such as radar sensing, sonar, and in the area of microwave medical imaging. Nevertheless, an analytical comparison of the methods has not been done. In this paper, the Point Spread Functions pertaining to the two methods are analytically determined. This allows a formal comparison of the two techniques, and to easily highlight how the performance depends on the configuration parameters, including frequency range, number of scatterers, and data discretization. It is demonstrated that the beamforming and holography basically achieve the same resolution but beamforming requires a cheaper (less sensors) configuration.. PMID:27137336

  8. Beamforming and holography image formation methods: an analytic study.

    PubMed

    Solimene, Raffaele; Cuccaro, Antonio; Ruvio, Giuseppe; Tapia, Daniel Flores; O'Halloran, Martin

    2016-04-18

    Beamforming and holographic imaging procedures are widely used in many applications such as radar sensing, sonar, and in the area of microwave medical imaging. Nevertheless, an analytical comparison of the methods has not been done. In this paper, the Point Spread Functions pertaining to the two methods are analytically determined. This allows a formal comparison of the two techniques, and to easily highlight how the performance depends on the configuration parameters, including frequency range, number of scatterers, and data discretization. It is demonstrated that the beamforming and holography basically achieve the same resolution but beamforming requires a cheaper (less sensors) configuration..

  9. Uncertainty profiles for the validation of analytical methods.

    PubMed

    Saffaj, T; Ihssane, B

    2011-09-15

    This article aims to expose a new global strategy for the validation of analytical methods and the estimation of measurement uncertainty. Our purpose is to allow to researchers in the field of analytical chemistry get access to a powerful tool for the evaluation of quantitative analytical procedures. Indeed, the proposed strategy facilitates analytical validation by providing a decision tool based on the uncertainty profile and the β-content tolerance interval. Equally important, this approach allows a good estimate of measurement uncertainty by using data validation and without recourse to other additional experiments. In the example below, we confirmed the applicability of this new strategy for the validation of a chromatographic bioanalytical method and the good estimate of the measurement uncertainty without referring to any extra effort and additional experiments. A comparative study with the SFSTP approach showed that both strategies have selected the same calibration functions. The holistic character of the measurement uncertainty compared to the total error was influenced by our choice of profile uncertainty. Nevertheless, we think that the adoption of the uncertainty in the validation stage controls the risk of using the analytical method in routine phase.

  10. Current Methods in Sedimentation Velocity and Sedimentation Equilibrium Analytical Ultracentrifugation

    PubMed Central

    Zhao, Huaying; Brautigam, Chad A.; Ghirlando, Rodolfo; Schuck, Peter

    2013-01-01

    Significant progress in the interpretation of analytical ultracentrifugation (AUC) data in the last decade has led to profound changes in the practice of AUC, both for sedimentation velocity (SV) and sedimentation equilibrium (SE). Modern computational strategies have allowed for the direct modeling of the sedimentation process of heterogeneous mixtures, resulting in SV size-distribution analyses with significantly improved detection limits and strongly enhanced resolution. These advances have transformed the practice of SV, rendering it the primary method of choice for most existing applications of AUC, such as the study of protein self- and hetero-association, the study of membrane proteins, and applications in biotechnology. New global multi-signal modeling and mass conservation approaches in SV and SE, in conjunction with the effective-particle framework for interpreting the sedimentation boundary structure of interacting systems, as well as tools for explicit modeling of the reaction/diffusion/sedimentation equations to experimental data, have led to more robust and more powerful strategies for the study of reversible protein interactions and multi-protein complexes. Furthermore, modern mathematical modeling capabilities have allowed for a detailed description of many experimental aspects of the acquired data, thus enabling novel experimental opportunities, with important implications for both sample preparation and data acquisition. The goal of the current commentary is to supplement previous AUC protocols, Current Protocols in Protein Science 20.3 (1999) and 20.7 (2003), and 7.12 (2008), and provide an update describing the current tools for the study of soluble proteins, detergent-solubilized membrane proteins and their interactions by SV and SE. PMID:23377850

  11. An analytical study for the design of advanced rotor airfoils

    NASA Technical Reports Server (NTRS)

    Kemp, L. D.

    1973-01-01

    A theoretical study has been conducted to design and evaluate two airfoils for helicopter rotors. The best basic shape, designed with a transonic hodograph design method, was modified to meet subsonic criteria. One airfoil had an additional constraint for low pitching-moment at the transonic design point. Airfoil characteristics were predicted. Results of a comparative analysis of helicopter performance indicate that the new airfoils will produce reduced rotor power requirements compared to the NACA 0012. The hodograph design method, written in CDC Algol, is listed and described.

  12. Analytical Methods for Detonation Residues of Insensitive Munitions

    NASA Astrophysics Data System (ADS)

    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.

  13. A New Analytic Alignment Method for a SINS.

    PubMed

    Tan, Caiming; Zhu, Xinhua; Su, Yan; Wang, Yu; Wu, Zhiqiang; Gu, Dongbing

    2015-01-01

    Analytic alignment is a type of self-alignment for a Strapdown inertial navigation system (SINS) that is based solely on two non-collinear vectors, which are the gravity and rotational velocity vectors of the Earth at a stationary base on the ground. The attitude of the SINS with respect to the Earth can be obtained directly using the TRIAD algorithm given two vector measurements. For a traditional analytic coarse alignment, all six outputs from the inertial measurement unit (IMU) are used to compute the attitude. In this study, a novel analytic alignment method called selective alignment is presented. This method uses only three outputs of the IMU and a few properties from the remaining outputs such as the sign and the approximate value to calculate the attitude. Simulations and experimental results demonstrate the validity of this method, and the precision of yaw is improved using the selective alignment method compared to the traditional analytic coarse alignment method in the vehicle experiment. The selective alignment principle provides an accurate relationship between the outputs and the attitude of the SINS relative to the Earth for a stationary base, and it is an extension of the TRIAD algorithm. The selective alignment approach has potential uses in applications such as self-alignment, fault detection, and self-calibration.

  14. A New Analytic Alignment Method for a SINS.

    PubMed

    Tan, Caiming; Zhu, Xinhua; Su, Yan; Wang, Yu; Wu, Zhiqiang; Gu, Dongbing

    2015-01-01

    Analytic alignment is a type of self-alignment for a Strapdown inertial navigation system (SINS) that is based solely on two non-collinear vectors, which are the gravity and rotational velocity vectors of the Earth at a stationary base on the ground. The attitude of the SINS with respect to the Earth can be obtained directly using the TRIAD algorithm given two vector measurements. For a traditional analytic coarse alignment, all six outputs from the inertial measurement unit (IMU) are used to compute the attitude. In this study, a novel analytic alignment method called selective alignment is presented. This method uses only three outputs of the IMU and a few properties from the remaining outputs such as the sign and the approximate value to calculate the attitude. Simulations and experimental results demonstrate the validity of this method, and the precision of yaw is improved using the selective alignment method compared to the traditional analytic coarse alignment method in the vehicle experiment. The selective alignment principle provides an accurate relationship between the outputs and the attitude of the SINS relative to the Earth for a stationary base, and it is an extension of the TRIAD algorithm. The selective alignment approach has potential uses in applications such as self-alignment, fault detection, and self-calibration. PMID:26556353

  15. A New Analytic Alignment Method for a SINS

    PubMed Central

    Tan, Caiming; Zhu, Xinhua; Su, Yan; Wang, Yu; Wu, Zhiqiang; Gu, Dongbing

    2015-01-01

    Analytic alignment is a type of self-alignment for a Strapdown inertial navigation system (SINS) that is based solely on two non-collinear vectors, which are the gravity and rotational velocity vectors of the Earth at a stationary base on the ground. The attitude of the SINS with respect to the Earth can be obtained directly using the TRIAD algorithm given two vector measurements. For a traditional analytic coarse alignment, all six outputs from the inertial measurement unit (IMU) are used to compute the attitude. In this study, a novel analytic alignment method called selective alignment is presented. This method uses only three outputs of the IMU and a few properties from the remaining outputs such as the sign and the approximate value to calculate the attitude. Simulations and experimental results demonstrate the validity of this method, and the precision of yaw is improved using the selective alignment method compared to the traditional analytic coarse alignment method in the vehicle experiment. The selective alignment principle provides an accurate relationship between the outputs and the attitude of the SINS relative to the Earth for a stationary base, and it is an extension of the TRIAD algorithm. The selective alignment approach has potential uses in applications such as self-alignment, fault detection, and self-calibration. PMID:26556353

  16. ANALYTICAL METHOD READINESS FOR THE CONTAMINANT CANDIDATE LIST

    EPA Science Inventory

    The Contaminant Candidate List (CCL), which was promulgated in March 1998, includes 50 chemical and 10 microbiological contaminants/contaminant groups. At the time of promulgation, analytical methods were available for 6 inorganic and 28 organic contaminants. Since then, 4 anal...

  17. Analytical chemistry methods for metallic core components: Revision March 1985

    SciTech Connect

    Not Available

    1985-03-01

    This standard provides analytical chemistry methods for the analysis of alloys used to fabricate core components. These alloys are 302, 308, 316, 316-Ti, and 321 stainless steels and 600 and 718 Inconels and they may include other 300-series stainless steels.

  18. 40 CFR 161.180 - Enforcement analytical method.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Enforcement analytical method. 161.180 Section 161.180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Product Chemistry Data...

  19. 40 CFR 766.16 - Developing the analytical test method.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Developing the analytical test method. 766.16 Section 766.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT DIBENZO-PARA-DIOXINS/DIBENZOFURANS General Provisions § 766.16 Developing...

  20. 40 CFR 766.16 - Developing the analytical test method.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Developing the analytical test method. 766.16 Section 766.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT DIBENZO-PARA-DIOXINS/DIBENZOFURANS General Provisions § 766.16 Developing...

  1. 40 CFR 766.16 - Developing the analytical test method.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Developing the analytical test method. 766.16 Section 766.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT DIBENZO-PARA-DIOXINS/DIBENZOFURANS General Provisions § 766.16 Developing...

  2. 40 CFR 766.16 - Developing the analytical test method.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Developing the analytical test method. 766.16 Section 766.16 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT DIBENZO-PARA-DIOXINS/DIBENZOFURANS General Provisions § 766.16 Developing...

  3. 40 CFR 161.180 - Enforcement analytical method.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Enforcement analytical method. 161.180 Section 161.180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Product Chemistry Data...

  4. 40 CFR 161.180 - Enforcement analytical method.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Enforcement analytical method. 161.180 Section 161.180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS DATA REQUIREMENTS FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Product Chemistry Data...

  5. Analytic energy gradient for the projected Hartree-Fock method

    NASA Astrophysics Data System (ADS)

    Schutski, Roman; Jiménez-Hoyos, Carlos A.; Scuseria, Gustavo E.

    2014-05-01

    We derive and implement the analytic energy gradient for the symmetry Projected Hartree-Fock (PHF) method avoiding the solution of coupled-perturbed HF-like equations, as in the regular unprojected method. Our formalism therefore has mean-field computational scaling and cost, despite the elaborate multi-reference character of the PHF wave function. As benchmark examples, we here apply our gradient implementation to the ortho-, meta-, and para-benzyne biradicals, and discuss their equilibrium geometries and vibrational frequencies.

  6. Recent developments in detection methods for microfabricated analytical devices.

    PubMed

    Schwarz, M A; Hauser, P C

    2001-09-01

    Sensitive detection in microfluidic analytical devices is a challenge because of the extremely small detection volumes available. Considerable efforts have been made lately to further address this aspect and to investigate techniques other than fluorescence. Among the newly introduced techniques are the optical methods of chemiluminescence, refraction and thermooptics, as well as the electrochemical methods of amperometry, conductimetry and potentiometry. Developments are also in progress to create miniaturized plasma-emission spectrometers and sensitive detectors for gas-chromatographic separations.

  7. Advanced reliability methods - A review

    NASA Astrophysics Data System (ADS)

    Forsyth, David S.

    2016-02-01

    There are a number of challenges to the current practices for Probability of Detection (POD) assessment. Some Nondestructive Testing (NDT) methods, especially those that are image-based, may not provide a simple relationship between a scalar NDT response and a damage size. Some damage types are not easily characterized by a single scalar metric. Other sensing paradigms, such as structural health monitoring, could theoretically replace NDT but require a POD estimate. And the cost of performing large empirical studies to estimate POD can be prohibitive. The response of the research community has been to develop new methods that can be used to generate the same information, POD, in a form that can be used by engineering designers. This paper will highlight approaches to image-based data and complex defects, Model Assisted POD estimation, and Bayesian methods for combining information. This paper will also review the relationship of the POD estimate, confidence bounds, tolerance bounds, and risk assessment.

  8. Understanding Fluorescence Measurements through a Guided-Inquiry and Discovery Experiment in Advanced Analytical Laboratory

    ERIC Educational Resources Information Center

    Wilczek-Vera, Grazyna; Salin, Eric Dunbar

    2011-01-01

    An experiment on fluorescence spectroscopy suitable for an advanced analytical laboratory is presented. Its conceptual development used a combination of the expository and discovery styles. The "learn-as-you-go" and direct "hands-on" methodology applied ensures an active role for a student in the process of visualization and discovery of concepts.…

  9. A Comprehensive Microfluidics Device Construction and Characterization Module for the Advanced Undergraduate Analytical Chemistry Laboratory

    ERIC Educational Resources Information Center

    Piunno, Paul A. E.; Zetina, Adrian; Chu, Norman; Tavares, Anthony J.; Noor, M. Omair; Petryayeva, Eleonora; Uddayasankar, Uvaraj; Veglio, Andrew

    2014-01-01

    An advanced analytical chemistry undergraduate laboratory module on microfluidics that spans 4 weeks (4 h per week) is presented. The laboratory module focuses on comprehensive experiential learning of microfluidic device fabrication and the core characteristics of microfluidic devices as they pertain to fluid flow and the manipulation of samples.…

  10. Recent advances in lattice Boltzmann methods

    SciTech Connect

    Chen, S.; Doolen, G.D.; He, X.; Nie, X.; Zhang, R.

    1998-12-31

    In this paper, the authors briefly present the basic principles of lattice Boltzmann method and summarize recent advances of the method, including the application of the lattice Boltzmann method for fluid flows in MEMS and simulation of the multiphase mixing and turbulence.

  11. Analytical methods for physicochemical characterization of antibody drug conjugates

    PubMed Central

    Wakankar, Aditya; Chen, Yan; Gokarn, Yatin

    2011-01-01

    Antibody-drug conjugates (ADCs), produced through the chemical linkage of a potent small molecule cytotoxin (drug) to a monoclonal antibody, have more complex and heterogeneous structures than the corresponding antibodies. This review describes the analytical methods that have been used in their physicochemical characterization. The selection of the most appropriate methods for a specific ADC is heavily dependent on the properties of the linker, the drug and the choice of attachment sites (lysines, inter-chain cysteines, Fc glycans). Improvements in analytical techniques such as protein mass spectrometry and capillary electrophoresis have significantly increased the quality of information that can be obtained for use in product and process characterization and for routine lot release and stability testing. PMID:21441786

  12. Analytical method for determination of benzene-arsenic acids

    SciTech Connect

    Mitchell, G.L.; Bayse, G.S.

    1988-01-01

    A sensitive analytical method has been modified for use in determination of several benzenearsonic acids, including arsanilic acid (p-aminobenzenearsonic acid), Roxarsone (3-nitro-4-hydroxybenzenearsonic acid), and p-ureidobenzene arsonic acid. Controlled acid hydrolysis of these compounds produces a quantitative yield of arsenate, which is measured colorimetrically as the molybdenum blue complex at 865 nm. The method obeys Beer's Law over the micromolar concentration range. These benzenearsonic acids are routinely used as feed additives in poultry and swine. This method should be useful in assessing tissue levels of the arsenicals in appropriate extracts.

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

    PubMed

    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.

  14. Active controls: A look at analytical methods and associated tools

    NASA Technical Reports Server (NTRS)

    Newsom, J. R.; Adams, W. M., Jr.; Mukhopadhyay, V.; Tiffany, S. H.; Abel, I.

    1984-01-01

    A review of analytical methods and associated tools for active controls analysis and design problems is presented. Approaches employed to develop mathematical models suitable for control system analysis and/or design are discussed. Significant efforts have been expended to develop tools to generate the models from the standpoint of control system designers' needs and develop the tools necessary to analyze and design active control systems. Representative examples of these tools are discussed. Examples where results from the methods and tools have been compared with experimental data are also presented. Finally, a perspective on future trends in analysis and design methods is presented.

  15. Analytical Methods for Measuring Mercury in Water, Sediment and Biota

    SciTech Connect

    Lasorsa, Brenda K.; Gill, Gary A.; Horvat, Milena

    2012-06-07

    Mercury (Hg) exists in a large number of physical and chemical forms with a wide range of properties. Conversion between these different forms provides the basis for mercury's complex distribution pattern in local and global cycles and for its biological enrichment and effects. Since the 1960’s, the growing awareness of environmental mercury pollution has stimulated the development of more accurate, precise and efficient methods of determining mercury and its compounds in a wide variety of matrices. During recent years new analytical techniques have become available that have contributed significantly to the understanding of mercury chemistry in natural systems. In particular, these include ultra sensitive and specific analytical equipment and contamination-free methodologies. These improvements allow for the determination of total mercury as well as major species of mercury to be made in water, sediments and soils, and biota. Analytical methods are selected depending on the nature of the sample, the concentration levels of mercury, and what species or fraction is to be quantified. The terms “speciation” and “fractionation” in analytical chemistry were addressed by the International Union for Pure and Applied Chemistry (IUPAC) which published guidelines (Templeton et al., 2000) or recommendations for the definition of speciation analysis. "Speciation analysis is the analytical activity of identifying and/or measuring the quantities of one or more individual chemical species in a sample. The chemical species are specific forms of an element defined as to isotopic composition, electronic or oxidation state, and/or complex or molecular structure. The speciation of an element is the distribution of an element amongst defined chemical species in a system. In case that it is not possible to determine the concentration of the different individual chemical species that sum up the total concentration of an element in a given matrix, meaning it is impossible to

  16. Analytical Methods for Biomass Characterization during Pretreatment and Bioconversion

    SciTech Connect

    Pu, Yunqiao; Meng, Xianzhi; Yoo, Chang Geun; Li, Mi; Ragauskas, Arthur J

    2016-01-01

    Lignocellulosic biomass has been introduced as a promising resource for alternative fuels and chemicals because of its abundance and complement for petroleum resources. Biomass is a complex biopolymer and its compositional and structural characteristics largely vary depending on its species as well as growth environments. Because of complexity and variety of biomass, understanding its physicochemical characteristics is a key for effective biomass utilization. Characterization of biomass does not only provide critical information of biomass during pretreatment and bioconversion, but also give valuable insights on how to utilize the biomass. For better understanding biomass characteristics, good grasp and proper selection of analytical methods are necessary. This chapter introduces existing analytical approaches that are widely employed for biomass characterization during biomass pretreatment and conversion process. Diverse analytical methods using Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy for biomass characterization are reviewed. In addition, biomass accessibility methods by analyzing surface properties of biomass are also summarized in this chapter.

  17. Analytical method for distribution of metallic gasket contact stress

    NASA Astrophysics Data System (ADS)

    Feng, Xiu; Gu, Boqing; Wei, Long; Sun, Jianjun

    2008-11-01

    Metallic gasket seals have been widely used in chemical and petrochemical plants. The failure of sealing system will lead to enormous pecuniary loss, serious environment pollution and personal injury accident. The failure of sealing systems is mostly caused not by the strength of flanges or bolts but by the leakage of the connections. The leakage behavior of bolted flanged connections is related to the gasket contact stress. In particular, the non-uniform distribution of this stress in the radial direction caused by the flange rotational flexibility has a major influence on the tightness of bolted flanged connections. In this paper, based on Warters method and considering the operating pressure, the deformation of the flanges is analyzed theoretically, and the formula for calculating the angle of rotation of the flanges is derived, based on which and the mechanical property of the gasket material, the method for calculating the gasket contact stresses is put forward. The maximum stress at the gasket outer flank calculated by the analytical method is lower than that obtained by numerical simulation, but the mean stresses calculated by the two methods are nearly the same. The analytical method presented in this paper can be used as an engineering method for designing the metallic gasket connections.

  18. Analytical Method for Measuring Cosmogenic (35)S in Natural Waters.

    PubMed

    Urióstegui, Stephanie H; Bibby, Richard K; Esser, Bradley K; Clark, Jordan F

    2015-06-16

    Cosmogenic sulfur-35 in water as dissolved sulfate ((35)SO4) has successfully been used as an intrinsic hydrologic tracer in low-SO4, high-elevation basins. Its application in environmental waters containing high SO4 concentrations has been limited because only small amounts of SO4 can be analyzed using current liquid scintillation counting (LSC) techniques. We present a new analytical method for analyzing large amounts of BaSO4 for (35)S. We quantify efficiency gains when suspending BaSO4 precipitate in Inta-Gel Plus cocktail, purify BaSO4 precipitate to remove dissolved organic matter, mitigate interference of radium-226 and its daughter products by selection of high purity barium chloride, and optimize LSC counting parameters for (35)S determination in larger masses of BaSO4. Using this improved procedure, we achieved counting efficiencies that are comparable to published LSC techniques despite a 10-fold increase in the SO4 sample load. (35)SO4 was successfully measured in high SO4 surface waters and groundwaters containing low ratios of (35)S activity to SO4 mass demonstrating that this new analytical method expands the analytical range of (35)SO4 and broadens the utility of (35)SO4 as an intrinsic tracer in hydrologic settings. PMID:25981756

  19. Development of A High Throughput Method Incorporating Traditional Analytical Devices

    PubMed Central

    White, C. C.; Embree, E.; Byrd, W. E; Patel, A. R.

    2004-01-01

    A high-throughput (high throughput is the ability to process large numbers of samples) and companion informatics system has been developed and implemented. High throughput is defined as the ability to autonomously evaluate large numbers of samples, while an informatics system provides the software control of the physical devices, in addition to the organization and storage of the generated electronic data. This high throughput system includes both an ultra-violet and visible light spectrometer (UV-Vis) and a Fourier transform infrared spectrometer (FTIR) integrated with a multi sample positioning table. This method is designed to quantify changes in polymeric materials occurring from controlled temperature, humidity and high flux UV exposures. The integration of the software control of these analytical instruments within a single computer system is presented. Challenges in enhancing the system to include additional analytical devices are discussed. PMID:27366626

  20. An analytical method for regional dental manpower training.

    PubMed

    Mulvey, P J; Foley, W J; Schneider, D P

    1978-07-01

    This paper presents an analytical method for dental manpower planning for use by Health Systems Agencies. The planning methods discard geopolitical boundaries in favor of Dental Service Areas (DSA). A method for defining DSAs by aggregating Minor Civil Divisions based on current population mobility and current distribution of dentists is presented. The Dental Manpower Balance Model (DMBM) is presented to calculate shortages (or surpluses) of dentists. This model uses sociodemographic data to calculate the demand for dental services and age adjusted productivity measures to calculate the effective supply of dentists. A case study for the HSA region in Northeastern New York is presented. The case study demonstrates that, although the planning methods are quite simple, they are more flexible and produce more sensitive results than the normative ratio method of manpower planning. PMID:10308627

  1. Comparison of analytical methods for calculation of wind loads

    NASA Technical Reports Server (NTRS)

    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.

  2. A new analytical method for groundwater recharge and discharge estimation

    NASA Astrophysics Data System (ADS)

    Liang, Xiuyu; Zhang, You-Kuan

    2012-07-01

    SummaryA new analytical method was proposed for groundwater recharge and discharge estimation in an unconfined aquifer. The method is based on an analytical solution to the Boussinesq equation linearized in terms of h2, where h is the water table elevation, with a time-dependent source term. The solution derived was validated with numerical simulation and was shown to be a better approximation than an existing solution to the Boussinesq equation linearized in terms of h. By calibrating against the observed water levels in a monitoring well during a period of 100 days, we shown that the method proposed in this study can be used to estimate daily recharge (R) and evapotranspiration (ET) as well as the lateral drainage. It was shown that the total R was reasonably estimated with a water-table fluctuation (WTF) method if the water table measurements away from a fixed-head boundary were used, but the total ET was overestimated and the total net recharge was underestimated because of the lack of consideration of lateral drainage and aquifer storage in the WTF method.

  3. Analytical investigation of thermal barrier coatings on advanced power generation gas turbines

    NASA Technical Reports Server (NTRS)

    Amos, D. J.

    1977-01-01

    An analytical investigation of present and advanced gas turbine power generation cycles incorporating thermal barrier turbine component coatings was performed. Approximately 50 parametric points considering simple, recuperated, and combined cycles (including gasification) with gas turbine inlet temperatures from current levels through 1644K (2500 F) were evaluated. The results indicated that thermal barriers would be an attractive means to improve performance and reduce cost of electricity for these cycles. A recommended thermal barrier development program has been defined.

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

    PubMed

    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.

  5. Gaussian Analytic Centroiding method of star image of star tracker

    NASA Astrophysics Data System (ADS)

    Wang, Haiyong; Xu, Ershuai; Li, Zhifeng; Li, Jingjin; Qin, Tianmu

    2015-11-01

    The energy distribution of an actual star image coincides with the Gaussian law statistically in most cases, so the optimized processing algorithm about star image centroiding should be constructed also by following Gaussian law. For a star image spot covering a certain number of pixels, the marginal distribution of the gray accumulation on rows and columns are shown and analyzed, based on which the formulas of Gaussian Analytic Centroiding method (GAC) are deduced, and the robustness is also promoted due to the inherited filtering effect of gray accumulation. Ideal reference star images are simulated by the PSF (point spread function) with integral form. Precision and speed tests for the Gaussian Analytic formulas are conducted under three scenarios of Gaussian radius (0.5, 0.671, 0.8 pixel), The simulation results show that the precision of GAC method is better than that of the other given algorithms when the Gaussian radius is not bigger than 5 × 5 pixel window, a widely used parameter. Above all, the algorithm which consumes the least time is still the novel GAC method. GAC method helps to promote the comprehensive performance in the attitude determination of a star tracker.

  6. Organic analysis and analytical methods development: FY 1995 progress report

    SciTech Connect

    Clauss, S.A.; Hoopes, V.; Rau, J.

    1995-09-01

    This report describes the status of organic analyses and developing analytical methods to account for the organic components in Hanford waste tanks, with particular emphasis 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-103 (Tank 103-SY). The analytical data are to serve as an example of the status of methods development and application. Samples of the convective and nonconvective layers from Tank 103-SY were analyzed for total organic carbon (TOC). The TOC value obtained for the nonconvective layer using the hot persulfate method was 10,500 {mu}g C/g. The TOC value obtained from samples of Tank 101-SY was 11,000 {mu}g C/g. The average value for the TOC of the convective layer was 6400 {mu}g C/g. Chelator and chelator fragments in Tank 103-SY samples were identified using derivatization. gas chromatography/mass spectrometry (GC/MS). Organic components were quantified using GC/flame ionization detection. Major components in both the convective and nonconvective-layer samples include ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), succinic acid, nitrosoiminodiacetic acid (NIDA), citric acid, and ethylenediaminetriacetic acid (ED3A). Preliminary results also indicate the presence of C16 and C18 carboxylic acids in the nonconvective-layer sample. Oxalic acid was one of the major components in the nonconvective layer as determined by derivatization GC/flame ionization detection.

  7. Analytical methods for kinetic studies of biological interactions: A review.

    PubMed

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

    2015-09-10

    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.

  8. Evolution of microbiological analytical methods for dairy industry needs

    PubMed Central

    Sohier, Danièle; Pavan, Sonia; Riou, Armelle; Combrisson, Jérôme; Postollec, Florence

    2014-01-01

    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 Polymerase chain reaction-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. PMID:24570675

  9. Analytical methods for kinetic studies of biological interactions: A review.

    PubMed

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

    2015-09-10

    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

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

    PubMed Central

    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

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

    NASA Technical Reports Server (NTRS)

    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.

  12. Evolution of microbiological analytical methods for dairy industry needs.

    PubMed

    Sohier, Danièle; Pavan, Sonia; Riou, Armelle; Combrisson, Jérôme; Postollec, Florence

    2014-01-01

    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 Polymerase chain reaction-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.

  13. Advanced analysis methods in particle physics

    SciTech Connect

    Bhat, Pushpalatha C.; /Fermilab

    2010-10-01

    Each generation of high energy physics experiments is grander in scale than the previous - more powerful, more complex and more demanding in terms of data handling and analysis. The spectacular performance of the Tevatron and the beginning of operations of the Large Hadron Collider, have placed us at the threshold of a new era in particle physics. The discovery of the Higgs boson or another agent of electroweak symmetry breaking and evidence of new physics may be just around the corner. The greatest challenge in these pursuits is to extract the extremely rare signals, if any, from huge backgrounds arising from known physics processes. The use of advanced analysis techniques is crucial in achieving this goal. In this review, I discuss the concepts of optimal analysis, some important advanced analysis methods and a few examples. The judicious use of these advanced methods should enable new discoveries and produce results with better precision, robustness and clarity.

  14. Flue gas desulfurization (FGD) chemistry and analytical methods handbook

    SciTech Connect

    Noblett, J.G.; Burke, J.M.

    1990-08-01

    The purpose of this handbook is to provide a comprehensive guide to sampling, analytical, and physical test methods essential to the operation, maintenance, and understanding of flue gas desulfurization (FGD) system chemistry. EPRI sponsored the first edition of this three-volume report in response to the needs of electric utility personnel responsible for establishing and operating commercial FGD analytical laboratories. The second, revised editions of Volumes 1 and 2 were prompted by the results of research into various non-standard aspects of FGD system chemistry. Volume 1 of the handbook explains FGD system chemistry in the detail necessary to understand how the processes operate and how process performance indicators can be used to optimize system operation. Volume 2 includes 63 physical-testing and chemical-analysis methods for reagents, slurries, and solids, and information on the applicability of individual methods to specific FGD systems. Volume 3 contains instructions for FGD solution chemistry computer program designated by EPRI as FGDLIQEQ. Executable on IBM-compatible personal computers, this program calculates the concentrations (activities) of chemical species (ions) in scrubber liquor and can calculate driving forces for important chemical reactions such as S0{sub 2} absorption and calcium sulfite and sulfate precipitation. This program and selected chemical analyses will help an FGD system operator optimize system performance, prevent many potential process problems, and define solutions to existing problems. 22 refs., 17 figs., 28 tabs.

  15. Performance of analytical methods for tomographic gamma scanning

    SciTech Connect

    Prettyman, T.H.; Mercer, D.J.

    1997-06-01

    The use of gamma-ray computerized tomography for nondestructive assay of radioactive materials has led to the development of specialized analytical methods. Over the past few years, Los Alamos has developed and implemented a computer code, called ARC-TGS, for the analysis of data obtained by tomographic gamma scanning (TGS). ARC-TGS reduces TGS transmission and emission tomographic data, providing the user with images of the sample contents, the activity or mass of selected radionuclides, and an estimate of the uncertainty in the measured quantities. The results provided by ARC-TGS can be corrected for self-attenuation when the isotope of interest emits more than one gamma-ray. In addition, ARC-TGS provides information needed to estimate TGS quantification limits and to estimate the scan time needed to screen for small amounts of radioactivity. In this report, an overview of the analytical methods used by ARC-TGS is presented along with an assessment of the performance of these methods for TGS.

  16. Advances in Analytical and Numerical Dispersion Modeling of Pollutants Releasing from an Area-source

    NASA Astrophysics Data System (ADS)

    Nimmatoori, Praneeth

    The air quality near agricultural activities such as tilling, plowing, harvesting, and manure application is of main concern because they release fine particulate matter into the atmosphere. These releases are modeled as area-sources in the air quality modeling research. None of the currently available dispersion models relate and incorporate physical characteristics and meteorological conditions for modeling the dispersion and deposition of particulates emitting from such area-sources. This knowledge gap was addressed by developing the advanced analytical and numerical methods for modeling the dispersion of particulate matter. The development, application, and evaluation of new dispersion modeling methods are discussed in detail in this dissertation. In the analytical modeling, a ground-level area source analytical dispersion model known as particulate matter deposition -- PMD was developed for predicting the concentrations of different particle sizes. Both the particle dynamics (particle physical characteristics) and meteorological conditions which have significant effect on the dispersion of particulates were related and incorporated in the PMD model using the formulations of particle gravitational settling and dry deposition velocities. The modeled particle size concentrations of the PMD model were evaluated statistically after applying it to particulates released from a biosolid applied agricultural field. The evaluation of the PMD model using the statistical criteria concluded effective and successful inclusion of dry deposition theory for modeling particulate matter concentrations. A comprehensive review of analytical area-source dispersion models, which do not account for dry deposition and treat pollutants as gases, was conducted and determined three models -- the Shear, the Parker, and the Smith. A statistical evaluation of these dispersion models was conducted after applying them to two different field data sets and the statistical results concluded that

  17. Experimental validation of an analytical method of calculating photon distributions

    SciTech Connect

    Wells, R.G.; Celler, A.; Harrop, R.

    1996-12-31

    We have developed a method for analytically calculating photon distributions in SPECT projections. This method models primary photon distributions as well as first and second order Compton scattering and Rayleigh scattering. It uses no free fitting parameters and so the projections produced are completely determined by the characteristics of the SPECT camera system, the energy of the isotope, an estimate of the source distribution and an attenuation map of the scattering object. The method was previously validated by comparison with Monte Carlo simulations and we are now verifying its accuracy with respect to phantom experiments. We have performed experiments using a Siemens MS3 SPECT camera system for a point source (2mm in diameter) within a homogeneous water bath and a small spherical source (1cm in diameter) within both a homogeneous water cylinder and a non-homogeneous medium consisting of air and water. Our technique reproduces well the distribution of photons in the experimentally acquired projections.

  18. Method of Analytic Evolution of Flat Distribution Amplitudes in QCD

    NASA Astrophysics Data System (ADS)

    Tandogan, Asli; Radyushkin, Anatoly V.

    A new analytical method of performing ERBL evolution is described. The main goal is to develop an approach that works for distribution amplitudes that do not vanish at the end points, for which the standard method of expansion in Gegenbauer polynomials is inefficient. Two cases of the initial DA are considered: a purely flat DA, given by the same constant for all x, and an antisymmetric DA given by opposite constants for x > 1/2. For a purely flat DA, the evolution is governed by an overall (x\\bar {x})t dependence on the evolution parameter t times a factor that was calculated as an expansion in t. For an antisymmetric flat DA, an extra overall factor |1 - 2x|2t appears due to a jump at x = 1/2. A good convergence was observed in the t ≲ 1/2 region. For larger t, one can use the standard method of the Gegenbauer expansion.

  19. Cost estimating methods for advanced space systems

    NASA Technical Reports Server (NTRS)

    Cyr, Kelley

    1988-01-01

    The development of parametric cost estimating methods for advanced space systems in the conceptual design phase is discussed. The process of identifying variables which drive cost and the relationship between weight and cost are discussed. A theoretical model of cost is developed and tested using a historical data base of research and development projects.

  20. Using analytic network process for evaluating mobile text entry methods.

    PubMed

    Ocampo, Lanndon A; Seva, Rosemary R

    2016-01-01

    This paper highlights a preference evaluation methodology for text entry methods in a touch keyboard smartphone using analytic network process (ANP). Evaluation of text entry methods in literature mainly considers speed and accuracy. This study presents an alternative means for selecting text entry method that considers user preference. A case study was carried out with a group of experts who were asked to develop a selection decision model of five text entry methods. The decision problem is flexible enough to reflect interdependencies of decision elements that are necessary in describing real-life conditions. Results showed that QWERTY method is more preferred than other text entry methods while arrangement of keys is the most preferred criterion in characterizing a sound method. Sensitivity analysis using simulation of normally distributed random numbers under fairly large perturbation reported the foregoing results reliable enough to reflect robust judgment. The main contribution of this paper is the introduction of a multi-criteria decision approach in the preference evaluation of text entry methods.

  1. Analytical methods for the determination of personal care products in human samples: an overview.

    PubMed

    Jiménez-Díaz, I; Zafra-Gómez, A; Ballesteros, O; Navalón, A

    2014-11-01

    Personal care products (PCPs) are organic chemicals widely used in everyday human life. Nowadays, preservatives, UV-filters, antimicrobials and musk fragrances are widely used PCPs. Different studies have shown that some of these compounds can cause adverse health effects, such as genotoxicity, which could even lead to mutagenic or carcinogenic effects, or estrogenicity because of their endocrine disruption activity. Due to the absence of official monitoring protocols, there is an increasing demand of analytical methods that allow the determination of those compounds in human samples in order to obtain more information regarding their behavior and fate in the human body. The complexity of the biological matrices and the low concentration levels of these compounds make necessary the use of advanced sample treatment procedures that afford both, sample clean-up, to remove potentially interfering matrix components, as well as the concentration of analytes. In the present work, a review of the more recent analytical methods published in the scientific literature for the determination of PCPs in human fluids and tissue samples, is presented. The work focused on sample preparation and the analytical techniques employed.

  2. Leveraging advanced data analytics, machine learning, and metrology models to enable critical dimension metrology solutions for advanced integrated circuit nodes

    NASA Astrophysics Data System (ADS)

    Rana, Narender; Zhang, Yunlin; Kagalwala, Taher; Bailey, Todd

    2014-10-01

    Integrated circuit (IC) technology is changing in multiple ways: 193i to extreme ultraviolet exposure, planar to nonplanar device architecture, from single exposure lithography to multiple exposure and directed self-assembly (DSA) patterning, and so on. Critical dimension (CD) control requirement is becoming stringent and more exhaustive: CD and process windows are shrinking, three-sigma CD control of <2 nm is required in complex geometries, and a metrology uncertainty of <0.2 nm is required to achieve the target CD control for advanced IC nodes (e.g., 14, 10, and 7 nm nodes). There are fundamental capability and accuracy limits in all the metrology techniques that are detrimental to the success of advanced IC nodes. Reference or physical CD metrology is provided by atomic force microscopy (CD-AFM) and TEM while workhorse metrology is provided by CD-SEM, scatterometry, and model-based infrared reflectrometry (MBIR). Precision alone is not sufficient for moving forward. No single technique is sufficient to ensure the required accuracy of patterning. The accuracy of CD-AFM is ˜1 nm and the precision in TEM is poor due to limited statistics. CD scanning electron microscopy (CD-SEM), scatterometry, and MBIR need to be calibrated by reference measurements for ensuring the accuracy of patterned CDs and patterning models. There is a dire need for a measurement with <0.5 nm accuracy and the industry currently does not have that capability with inline measurements. Being aware of the capability gaps for various metrology techniques, we have employed data processing techniques and predictive data analytics, along with patterning simulation and metrology models and data integration techniques to selected applications demonstrating the potential solution and practicality of such an approach to enhance CD metrology accuracy. Data from multiple metrology techniques have been analyzed in multiple ways to extract information with associated uncertainties and integrated to extract

  3. Friedmann-Lemaitre cosmologies via roulettes and other analytic methods

    NASA Astrophysics Data System (ADS)

    Chen, Shouxin; Gibbons, Gary W.; Yang, Yisong

    2015-10-01

    In this work a series of methods are developed for understanding the Friedmann equation when it is beyond the reach of the Chebyshev theorem. First it will be demonstrated that every solution of the Friedmann equation admits a representation as a roulette such that information on the latter may be used to obtain that for the former. Next the Friedmann equation is integrated for a quadratic equation of state and for the Randall-Sundrum II universe, leading to a harvest of a rich collection of new interesting phenomena. Finally an analytic method is used to isolate the asymptotic behavior of the solutions of the Friedmann equation, when the equation of state is of an extended form which renders the integration impossible, and to establish a universal exponential growth law.

  4. A novel unified coding analytical method for Internet of Things

    NASA Astrophysics Data System (ADS)

    Sun, Hong; Zhang, JianHong

    2013-08-01

    This paper presents a novel unified coding analytical method for Internet of Things, which abstracts out the `displacement goods' and `physical objects', and expounds the relationship thereof. It details the item coding principles, establishes a one-to-one relationship between three-dimensional spatial coordinates of points and global manufacturers, can infinitely expand, solves the problem of unified coding in production phase and circulation phase with a novel unified coding method, and further explains how to update the item information corresponding to the coding in stages of sale and use, so as to meet the requirement that the Internet of Things can carry out real-time monitoring and intelligentized management to each item.

  5. GenoSets: Visual Analytic Methods for Comparative Genomics

    PubMed Central

    Cain, Aurora A.; Kosara, Robert; Gibas, Cynthia J.

    2012-01-01

    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. PMID:23056299

  6. GenoSets: visual analytic methods for comparative genomics.

    PubMed

    Cain, Aurora A; Kosara, Robert; Gibas, Cynthia J

    2012-01-01

    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. An analytical method for computing atomic contact areas in biomolecules.

    PubMed

    Mach, Paul; Koehl, Patrice

    2013-01-15

    We propose a new analytical method for detecting and computing contacts between atoms in biomolecules. It is based on the alpha shape theory and proceeds in three steps. First, we compute the weighted Delaunay triangulation of the union of spheres representing the molecule. In the second step, the Delaunay complex is filtered to derive the dual complex. Finally, contacts between spheres are collected. In this approach, two atoms i and j are defined to be in contact if their centers are connected by an edge in the dual complex. The contact areas between atom i and its neighbors are computed based on the caps formed by these neighbors on the surface of i; the total area of all these caps is partitioned according to their spherical Laguerre Voronoi diagram on the surface of i. This method is analytical and its implementation in a new program BallContact is fast and robust. We have used BallContact to study contacts in a database of 1551 high resolution protein structures. We show that with this new definition of atomic contacts, we generate realistic representations of the environments of atoms and residues within a protein. In particular, we establish the importance of nonpolar contact areas that complement the information represented by the accessible surface areas. This new method bears similarity to the tessellation methods used to quantify atomic volumes and contacts, with the advantage that it does not require the presence of explicit solvent molecules if the surface of the protein is to be considered. © 2012 Wiley Periodicals, Inc.

  8. An analytic method to compute star cluster luminosity statistics

    NASA Astrophysics Data System (ADS)

    da Silva, Robert L.; Krumholz, Mark R.; Fumagalli, Michele; Fall, S. Michael

    2014-03-01

    The luminosity distribution of the brightest star clusters in a population of galaxies encodes critical pieces of information about how clusters form, evolve and disperse, and whether and how these processes depend on the large-scale galactic environment. However, extracting constraints on models from these data is challenging, in part because comparisons between theory and observation have traditionally required computationally intensive Monte Carlo methods to generate mock data that can be compared to observations. We introduce a new method that circumvents this limitation by allowing analytic computation of cluster order statistics, i.e. the luminosity distribution of the Nth most luminous cluster in a population. Our method is flexible and requires few assumptions, allowing for parametrized variations in the initial cluster mass function and its upper and lower cutoffs, variations in the cluster age distribution, stellar evolution and dust extinction, as well as observational uncertainties in both the properties of star clusters and their underlying host galaxies. The method is fast enough to make it feasible for the first time to use Markov chain Monte Carlo methods to search parameter space to find best-fitting values for the parameters describing cluster formation and disruption, and to obtain rigorous confidence intervals on the inferred values. We implement our method in a software package called the Cluster Luminosity Order-Statistic Code, which we have made publicly available.

  9. Comparison of four [sup 90]Sr groundwater analytical methods

    SciTech Connect

    Scarpitta, S.; Odin-McCabe, J.; Gaschott, R.; Meier, A.; Klug, E. . Analytical Services Lab.)

    1999-06-01

    Data are presented for 45 Long Island groundwater samples each measured for [sup 90]Sr using four different analytical methods. [sup 90]Sr levels were first established by two New York State certified laboratories, one of which used the US Environmental Protection Agency Radioactive Strontium in Drinking Water Method 905.0. Three of the [sup 90]Sr methods evaluated at Brookhaven National Laboratory can reduce analysis time by more than 50%. They were (a) an Environmental Measurements Laboratory Cerenkov technique and (b) two commercially available products that utilize strontium-specific crown-ethers supported on either a resin or membrane disk. Method independent inter-laboratory bias was < 12% based on [sup 90]Sr results obtained using both US Department of Energy/Environmental Measurements Laboratory and US EPA/National Environmental Radiation Laboratory samples of known activity concentration. Brookhaven National Laboratory prepared a National Institute of Standards and Technology traceable [sup 90]Sr tap-water sample used to quantify test method biases. With gas proportional or liquid scintillation counting, minimum detectable levels (MDLs) of 37 Bq m[sup [minus]3] (1 pCi L[sup [minus]1]) wee achievable for both crown-ether methods using a 1-L processed sample beta counted for 1 h.

  10. [Comparison of intestinal bacteria composition identified by various analytical methods].

    PubMed

    Fujisawa, Tomohiko

    2014-01-01

    Many different kinds of bacteria are normally found in the intestines of healthy humans and animals. To study the ecology and function of these intestinal bacteria, the culture method was fundamental until recent years, and suitable agar plates such as non-selective agar plates and several selective agar plates have been developed. Furthermore, the roll-tube, glove box, and plate-in-bottle methods have also been developed for the cultivation of fastidious anaerobes that predominantly colonize the intestine. Until recently, the evaluation of functional foods such as pre- and probiotics was mainly done using culture methods, and many valuable data were produced. On the other hand, genomic analysis such as the fluorescence in situ hybridization (FISH), quantitative PCR (qPCR), clone-library, denaturing gradient gel electrophoresis (DGGE), temperature gradient gel electrophoresis (TGGE), terminal-restriction fragment length polymorphism (T-RFLP) methods, and metagenome analysis have been used for the investigation of intestinal microbiota in recent years. The identification of bacteria is done by investigation of the phenotypic characteristics in culture methods, while rRNA genes are used as targets in genomic analysis. Here, I compare the fecal bacteria identified by various analytical methods.

  11. MICROORGANISMS IN BIOSOLIDS: ANALYTICAL METHODS DEVELOPMENT, STANDARDIZATION, AND VALIDATION

    EPA Science Inventory

    The objective of this presentation is to discuss pathogens of concern in biosolids, the analytical techniques used to evaluate microorganisms in biosolids, and to discuss standardization and validation of analytical protocols for microbes within such a complex matrix. Implicatio...

  12. Analytical Verifications in Cryogenic Testing of NGST Advanced Mirror System Demonstrators

    NASA Technical Reports Server (NTRS)

    Cummings, Ramona; Levine, Marie; VanBuren, Dave; Kegley, Jeff; Green, Joseph; Hadaway, James; Presson, Joan; Cline, Todd; Stahl, H. Philip (Technical Monitor)

    2002-01-01

    Ground based testing is a critical and costly part of component, assembly, and system verifications of large space telescopes. At such tests, however, with integral teamwork by planners, analysts, and test personnel, segments can be included to validate specific analytical parameters and algorithms at relatively low additional cost. This paper opens with strategy of analytical verification segments added to vacuum cryogenic testing of Advanced Mirror System Demonstrator (AMSD) assemblies. These AMSD assemblies incorporate material and architecture concepts being considered in the Next Generation Space Telescope (NGST) design. The test segments for workmanship testing, cold survivability, and cold operation optical throughput are supplemented by segments for analytical verifications of specific structural, thermal, and optical parameters. Utilizing integrated modeling and separate materials testing, the paper continues with support plan for analyses, data, and observation requirements during the AMSD testing, currently slated for late calendar year 2002 to mid calendar year 2003. The paper includes anomaly resolution as gleaned by authors from similar analytical verification support of a previous large space telescope, then closes with draft of plans for parameter extrapolations, to form a well-verified portion of the integrated modeling being done for NGST performance predictions.

  13. 21 CFR 530.24 - Procedure for announcing analytical methods for drug residue quantification.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Procedure for announcing analytical methods for...-Producing Animals § 530.24 Procedure for announcing analytical methods for drug residue quantification. (a) FDA may issue an order announcing a specific analytical method or methods for the quantification...

  14. Improved Tissue-Based Analytical Test Methods for Orellanine, a Biomarker of Cortinarius Mushroom Intoxication.

    PubMed

    Anantharam, Poojya; Shao, Dahai; Imerman, Paula M; Burrough, Eric; Schrunk, Dwayne; Sedkhuu, Tsevelmaa; Tang, Shusheng; Rumbeiha, Wilson

    2016-01-01

    Orellanine (OR) toxin is produced by mushrooms of the genus Cortinarius which grow in North America and in Europe. OR poisoning is characterized by severe oliguric acute renal failure, with a mortality rate of 10%-30%. Diagnosis of OR poisoning currently hinges on a history of ingestion of Cortinarius mushrooms and histopathology of renal biopsies. A key step in the diagnostic approach is analysis of tissues for OR. Currently, tissue-based analytical methods for OR are nonspecific and lack sensitivity. The objectives of this study were: (1) to develop definitive HPLC and LC-MS/MS tissue-based analytical methods for OR; and (2) to investigate toxicological effects of OR in mice. The HPLC limit of quantitation was 10 µg/g. For fortification levels of 15 µg/g to 50 µg/g OR in kidney, the relative standard deviation was between 1.3% and 9.8%, and accuracy was within 1.5% to 7.1%. A matrix-matched calibration curve was reproduced in this range with a correlation coefficient (r) of 0.97-0.99. The limit of detection was 20 ng/g for LC-MS/MS. In OR-injected mice, kidney OR concentrations were 97 ± 51 µg/g on Day 0 and 17 ± 1 µg/g on termination Day 3. Splenic and liver injuries were novel findings in this mouse model. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology. PMID:27213453

  15. Improved Tissue-Based Analytical Test Methods for Orellanine, a Biomarker of Cortinarius Mushroom Intoxication

    PubMed Central

    Anantharam, Poojya; Shao, Dahai; Imerman, Paula M.; Burrough, Eric; Schrunk, Dwayne; Sedkhuu, Tsevelmaa; Tang, Shusheng; Rumbeiha, Wilson

    2016-01-01

    Orellanine (OR) toxin is produced by mushrooms of the genus Cortinarius which grow in North America and in Europe. OR poisoning is characterized by severe oliguric acute renal failure, with a mortality rate of 10%–30%. Diagnosis of OR poisoning currently hinges on a history of ingestion of Cortinarius mushrooms and histopathology of renal biopsies. A key step in the diagnostic approach is analysis of tissues for OR. Currently, tissue-based analytical methods for OR are nonspecific and lack sensitivity. The objectives of this study were: (1) to develop definitive HPLC and LC-MS/MS tissue-based analytical methods for OR; and (2) to investigate toxicological effects of OR in mice. The HPLC limit of quantitation was 10 µg/g. For fortification levels of 15 µg/g to 50 µg/g OR in kidney, the relative standard deviation was between 1.3% and 9.8%, and accuracy was within 1.5% to 7.1%. A matrix-matched calibration curve was reproduced in this range with a correlation coefficient (r) of 0.97–0.99. The limit of detection was 20 ng/g for LC-MS/MS. In OR-injected mice, kidney OR concentrations were 97 ± 51 µg/g on Day 0 and 17 ± 1 µg/g on termination Day 3. Splenic and liver injuries were novel findings in this mouse model. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology. PMID:27213453

  16. Improved Tissue-Based Analytical Test Methods for Orellanine, a Biomarker of Cortinarius Mushroom Intoxication.

    PubMed

    Anantharam, Poojya; Shao, Dahai; Imerman, Paula M; Burrough, Eric; Schrunk, Dwayne; Sedkhuu, Tsevelmaa; Tang, Shusheng; Rumbeiha, Wilson

    2016-05-21

    Orellanine (OR) toxin is produced by mushrooms of the genus Cortinarius which grow in North America and in Europe. OR poisoning is characterized by severe oliguric acute renal failure, with a mortality rate of 10%-30%. Diagnosis of OR poisoning currently hinges on a history of ingestion of Cortinarius mushrooms and histopathology of renal biopsies. A key step in the diagnostic approach is analysis of tissues for OR. Currently, tissue-based analytical methods for OR are nonspecific and lack sensitivity. The objectives of this study were: (1) to develop definitive HPLC and LC-MS/MS tissue-based analytical methods for OR; and (2) to investigate toxicological effects of OR in mice. The HPLC limit of quantitation was 10 µg/g. For fortification levels of 15 µg/g to 50 µg/g OR in kidney, the relative standard deviation was between 1.3% and 9.8%, and accuracy was within 1.5% to 7.1%. A matrix-matched calibration curve was reproduced in this range with a correlation coefficient (r) of 0.97-0.99. The limit of detection was 20 ng/g for LC-MS/MS. In OR-injected mice, kidney OR concentrations were 97 ± 51 µg/g on Day 0 and 17 ± 1 µg/g on termination Day 3. Splenic and liver injuries were novel findings in this mouse model. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology. The new tissue-based analytical tests will improve diagnosis of OR poisoning, while the mouse model has yielded new data advancing knowledge on OR-induced pathology.

  17. Editorial: Latest methods and advances in biotechnology.

    PubMed

    Lee, Sang Yup; Jungbauer, Alois

    2014-01-01

    The latest "Biotech Methods and Advances" special issue of Biotechnology Journal continues the BTJ tradition of featuring the latest breakthroughs in biotechnology. The special issue is edited by our Editors-in-Chief, Prof. Sang Yup Lee and Prof. Alois Jungbauer and covers a wide array of topics in biotechnology, including the perennial favorite workhorses of the biotech industry, Chinese hamster ovary (CHO) cell and Escherichia coli.

  18. Polymeric vehicles for topical delivery and related analytical methods.

    PubMed

    Cho, Heui Kyoung; Cho, Jin Hun; Jeong, Seong Hoon; Cho, Dong Chul; Yeum, Jeong Hyun; Cheong, In Woo

    2014-04-01

    Recently a variety of polymeric vehicles, such as micelles, nanoparticles, and polymersomes, have been explored and some of them are clinically used to deliver therapeutic drugs through skin. In topical delivery, the polymeric vehicles as drug carrier should guarantee non-toxicity, long-term stability, and permeation efficacy for drugs, etc. For the development of the successful topical delivery system, it is of importance to develop the polymeric vehicles of well-defined intrinsic properties, such as molecular weights, HLB, chemical composition, topology, specific ligand conjugation and to investigate the effects of the properties on drug permeation behavior. In addition, the role of polymeric vehicles must be elucidated in in vitro and in vivo analyses. This article describes some important features of polymeric vehicles and corresponding analytical methods in topical delivery even though the application span of polymers has been truly broad in the pharmaceutical fields.

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

    PubMed

    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. PMID:27664687

  20. The Finite Analytic Method for steady and unsteady heat transfer problems

    NASA Technical Reports Server (NTRS)

    Chen, C.-J.; Li, P.

    1980-01-01

    A new numerical method called the Finite Analytical Method for solving partial differential equations is introduced. The basic idea of the finite analytic method is the incorporation of the local analytic solution in obtaining the numerical solution of the problem. The finite analytical method first divides the total region of the problem into small subregions in which local analytic solutions are obtained. Then an algebraic equation is derived from the local analytic solution for each subregion relating an interior nodal value at a point P in the subregion to its neighboring nodal values. The assembly of all the local analytic solutions thus provides the finite-analytic numerical solution of the problem. In this paper the finite analytic method is illustrated in solving steady and unsteady heat transfer problems.

  1. [Analytical methods for control of foodstuffs made from bioengineered plants].

    PubMed

    Chernysheva, O N; Sorokina, E Iu

    2013-01-01

    Foodstuffs made by modern biotechnology are requiring for special control. Analytical methods used for these purposes are being constantly perfected. When choosing a strategy for the analysis, several factors have to be assessed: specificity, sensitivity, practically of the method and time efficiency. To date, the GMO testing methods are mainly based on the inserted DNA sequences and newly produced proteins in GMOs. Protein detection methods are based mainly on ELISA. The specific detection of a novel protein synthesized by gene introduced during transformation constitutes an alternative approach for the identification of GMO. The genetic modification is not always specifically directed at the production of a novel protein and does not always result in protein expression levels sufficient for detection purposes. In addition, some proteins may be expressed only in specific parts of the plant or expressed at different levels in distinct parts of plant. As DNA is a rather stable molecule relative to proteins, it is preferred target for any kind of sample. These methods are more sensitive and specific than protein detection methods. PCR-based test can be categorized into several levels of specificity. The least specific methods are commonly called "screening methods" and relate to target DNA elements, such as promoters and terminators that are present in many different GMOs. For routine screening purpose regulatory elements 35S promoter, derived from the Cauliflower Mosaic Virus and the NOS terminator, derived from the nopaline synthase gene of Agrobacterium tumefaciens, are used as target sequences. The second level is "gene-specific methods". These methods target a part of the DNA harbouring the active gene associated with the specific genetic modification. The highest specificity is seen when the target is the unique junction found at the integration locus between the inserted DNA and the recipient genome. These are called "event-specific methods". For a

  2. [Analytical methods for control of foodstuffs made from bioengineered plants].

    PubMed

    Chernysheva, O N; Sorokina, E Iu

    2013-01-01

    Foodstuffs made by modern biotechnology are requiring for special control. Analytical methods used for these purposes are being constantly perfected. When choosing a strategy for the analysis, several factors have to be assessed: specificity, sensitivity, practically of the method and time efficiency. To date, the GMO testing methods are mainly based on the inserted DNA sequences and newly produced proteins in GMOs. Protein detection methods are based mainly on ELISA. The specific detection of a novel protein synthesized by gene introduced during transformation constitutes an alternative approach for the identification of GMO. The genetic modification is not always specifically directed at the production of a novel protein and does not always result in protein expression levels sufficient for detection purposes. In addition, some proteins may be expressed only in specific parts of the plant or expressed at different levels in distinct parts of plant. As DNA is a rather stable molecule relative to proteins, it is preferred target for any kind of sample. These methods are more sensitive and specific than protein detection methods. PCR-based test can be categorized into several levels of specificity. The least specific methods are commonly called "screening methods" and relate to target DNA elements, such as promoters and terminators that are present in many different GMOs. For routine screening purpose regulatory elements 35S promoter, derived from the Cauliflower Mosaic Virus and the NOS terminator, derived from the nopaline synthase gene of Agrobacterium tumefaciens, are used as target sequences. The second level is "gene-specific methods". These methods target a part of the DNA harbouring the active gene associated with the specific genetic modification. The highest specificity is seen when the target is the unique junction found at the integration locus between the inserted DNA and the recipient genome. These are called "event-specific methods". For a

  3. Simulation methods for advanced scientific computing

    SciTech Connect

    Booth, T.E.; Carlson, J.A.; Forster, R.A.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of the project was to create effective new algorithms for solving N-body problems by computer simulation. The authors concentrated on developing advanced classical and quantum Monte Carlo techniques. For simulations of phase transitions in classical systems, they produced a framework generalizing the famous Swendsen-Wang cluster algorithms for Ising and Potts models. For spin-glass-like problems, they demonstrated the effectiveness of an extension of the multicanonical method for the two-dimensional, random bond Ising model. For quantum mechanical systems, they generated a new method to compute the ground-state energy of systems of interacting electrons. They also improved methods to compute excited states when the diffusion quantum Monte Carlo method is used and to compute longer time dynamics when the stationary phase quantum Monte Carlo method is used.

  4. Analytical model for ring heater thermal compensation in the Advanced Laser Interferometer Gravitational-wave Observatory.

    PubMed

    Ramette, Joshua; Kasprzack, Marie; Brooks, Aidan; Blair, Carl; Wang, Haoyu; Heintze, Matthew

    2016-04-01

    Advanced laser interferometer gravitational-wave detectors use high laser power to achieve design sensitivity. A small part of this power is absorbed in the interferometer cavity mirrors where it creates thermal lenses, causing aberrations in the main laser beam that must be minimized by the actuation of "ring heaters," which are additional heater elements that are aimed to reduce the temperature gradients in the mirrors. In this article we derive the first, to the best of our knowledge, analytical model of the temperature field generated by an ideal ring heater. We express the resulting optical aberration contribution to the main laser beam in this axisymmetric case. Used in conjunction with wavefront measurements, our model provides a more complete understanding of the thermal state of the cavity mirrors and will allow a more efficient use of the ring heaters in the Advanced Laser Interferometer Gravitational-wave Observatory. PMID:27139664

  5. Analytical model for ring heater thermal compensation in the Advanced Laser Interferometer Gravitational-wave Observatory.

    PubMed

    Ramette, Joshua; Kasprzack, Marie; Brooks, Aidan; Blair, Carl; Wang, Haoyu; Heintze, Matthew

    2016-04-01

    Advanced laser interferometer gravitational-wave detectors use high laser power to achieve design sensitivity. A small part of this power is absorbed in the interferometer cavity mirrors where it creates thermal lenses, causing aberrations in the main laser beam that must be minimized by the actuation of "ring heaters," which are additional heater elements that are aimed to reduce the temperature gradients in the mirrors. In this article we derive the first, to the best of our knowledge, analytical model of the temperature field generated by an ideal ring heater. We express the resulting optical aberration contribution to the main laser beam in this axisymmetric case. Used in conjunction with wavefront measurements, our model provides a more complete understanding of the thermal state of the cavity mirrors and will allow a more efficient use of the ring heaters in the Advanced Laser Interferometer Gravitational-wave Observatory.

  6. Method of Analytic Evolution of Flat Distribution Amplitudes in QCD

    SciTech Connect

    Asli Tandogan, Anatoly V. Radyushkin

    2011-11-01

    A new analytical method of performing ERBL evolution is described. The main goal is to develop an approach that works for distribution amplitudes that do not vanish at the end points, for which the standard method of expansion in Gegenbauer polynomials is inefficient. Two cases of the initial DA are considered: a purely flat DA, given by the same constant for all x, and an antisymmetric DA given by opposite constants for x < 1/2 or x > 1/2. For a purely flat DA, the evolution is governed by an overall (x (1-x)){sup t} dependence on the evolution parameter t times a factor that was calculated as an expansion in t. For an antisymmetric flat DA, an extra overall factor |1-2x|{sup 2t} appears due to a jump at x = 1/2. A good convergence was observed in the t {approx}< 1/2 region. For larger t, one can use the standard method of the Gegenbauer expansion.

  7. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical, or... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Safe levels and analytical methods for food... § 530.22 Safe levels and analytical methods for food-producing animals. (a) FDA may establish a...

  8. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical, or regulatory criteria. (b) FDA may require the development of an acceptable analytical method for the... such an acceptable analytical method, the agency will publish notice of that requirement in the...

  9. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical, or regulatory criteria. (b) FDA may require the development of an acceptable analytical method for the... such an acceptable analytical method, the agency will publish notice of that requirement in the...

  10. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical, or regulatory criteria. (b) FDA may require the development of an acceptable analytical method for the... such an acceptable analytical method, the agency will publish notice of that requirement in the...

  11. 21 CFR 530.40 - Safe levels and availability of analytical methods.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Safe levels and availability of analytical methods... Safe levels and availability of analytical methods. (a) In accordance with § 530.22, the following safe... accordance with § 530.22, the following analytical methods have been accepted by FDA:...

  12. 21 CFR 530.22 - Safe levels and analytical methods for food-producing animals.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Safe levels and analytical methods for food... § 530.22 Safe levels and analytical methods for food-producing animals. (a) FDA may establish a safe... analytical method; or (3) Establish a safe level based on other appropriate scientific, technical,...

  13. Advance in methods studying the pharmacokinetics of polyphenols.

    PubMed

    Santos, Ana C; Costa, G; Veiga, F; Figueiredo, I V; Batista, M T; Ribeiro, António J

    2014-01-01

    Significant advances have been achieved during the past decade concerning the metabolism of polyphenol compounds in vitro, but scarce data has been presented about what really happens in vivo. Many studies on polyphenols to date have focused on the bioactivity of one specific molecule in aglycone form, often at supraphysiological doses, whereas foods contain complex, often poorly characterized mixtures with multiple additive or interfering activities. Whereas most studies up to the middle-late 1990s measured total aglycones in plasma and urine, after chemical or enzymatic deconjugation, or both, several recent works now report the polyphenol conjugate composition of plasma, urine, feces and/or tissues, after the administration of pure polyphenols or polyphenol-rich matrices. HPLC methods with electrochemical, mass spectrometric and fluorescence detection have adequate sensitivity. LC/UV-Vis methods have also been widely reported, but they are much less sensitive. Compared with electro-chemical and fluorescence detection, MS can quantify analytes without chromatographic separation, which leads to high throughput, presenting itself as the best choice to date. Regarding the experimental model to monitor the bioavailability of phenolic compounds, most published studies are based on human and animal models, with the majority using rodents, primates and recently the nematode Caenorhabditis elegans. This review focuses on the fundamentals of pharmacokinetic methods from the last 15 years and how the results are evaluated and validated. The types of analytical methods, animal models and biological matrices were used to better elucidate pharmacokinetics of polyphenols.

  14. Advanced Bayesian Method for Planetary Surface Navigation

    NASA Technical Reports Server (NTRS)

    Center, Julian

    2015-01-01

    Autonomous Exploration, Inc., has developed an advanced Bayesian statistical inference method that leverages current computing technology to produce a highly accurate surface navigation system. The method combines dense stereo vision and high-speed optical flow to implement visual odometry (VO) to track faster rover movements. The Bayesian VO technique improves performance by using all image information rather than corner features only. The method determines what can be learned from each image pixel and weighs the information accordingly. This capability improves performance in shadowed areas that yield only low-contrast images. The error characteristics of the visual processing are complementary to those of a low-cost inertial measurement unit (IMU), so the combination of the two capabilities provides highly accurate navigation. The method increases NASA mission productivity by enabling faster rover speed and accuracy. On Earth, the technology will permit operation of robots and autonomous vehicles in areas where the Global Positioning System (GPS) is degraded or unavailable.

  15. How to assess the quality of your analytical method?

    PubMed

    Topic, Elizabeta; Nikolac, Nora; Panteghini, Mauro; Theodorsson, Elvar; Salvagno, Gian Luca; Miler, Marijana; Simundic, Ana-Maria; Infusino, Ilenia; Nordin, Gunnar; Westgard, Sten

    2015-10-01

    Laboratory medicine is amongst the fastest growing fields in medicine, crucial in diagnosis, support of prevention and in the monitoring of disease for individual patients and for the evaluation of treatment for populations of patients. Therefore, high quality and safety in laboratory testing has a prominent role in high-quality healthcare. Applied knowledge and competencies of professionals in laboratory medicine increases the clinical value of laboratory results by decreasing laboratory errors, increasing appropriate utilization of tests, and increasing cost effectiveness. This collective paper provides insights into how to validate the laboratory assays and assess the quality of methods. It is a synopsis of the lectures at the 15th European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Continuing Postgraduate Course in Clinical Chemistry and Laboratory Medicine entitled "How to assess the quality of your method?" (Zagreb, Croatia, 24-25 October 2015). The leading topics to be discussed include who, what and when to do in validation/verification of methods, verification of imprecision and bias, verification of reference intervals, verification of qualitative test procedures, verification of blood collection systems, comparability of results among methods and analytical systems, limit of detection, limit of quantification and limit of decision, how to assess the measurement uncertainty, the optimal use of Internal Quality Control and External Quality Assessment data, Six Sigma metrics, performance specifications, as well as biological variation. This article, which continues the annual tradition of collective papers from the EFLM continuing postgraduate courses in clinical chemistry and laboratory medicine, aims to provide further contributions by discussing the quality of laboratory methods and measurements and, at the same time, to offer continuing professional development to the attendees.

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

    USGS Publications Warehouse

    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.

  17. An analytical method for predicting postwildfire peak discharges

    USGS Publications Warehouse

    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

  18. Analytical methods in bioassay-directed investigations of mutagenicity of air particulate material.

    PubMed

    Marvin, Christopher H; Hewitt, L Mark

    2007-01-01

    The combination of short-term bioassays and analytical chemical techniques has been successfully used in the identification of a variety of mutagenic compounds in complex mixtures. Much of the early work in the field of bioassay-directed fractionation resulted from the development of a short-term bacterial assay employing Salmonella typhimurium; this assay is commonly known as the Ames assay. Ideally, analytical methods for assessment of mutagenicity of any environmental matrix should exhibit characteristics including high capacity, good selectivity, good analytical resolution, non-destructiveness, and reproducibility. A variety of extraction solvents have been employed in investigations of mutagenicity of air particulate; sequential combination of dichloromethane followed by methanol is most popular. Soxhlet extraction has been the most common extraction method, followed by sonication. Attempts at initial fractionation using different extraction solvents have met with limited success and highlight the need for fractionation schemes applicable to moderately polar and polar mutagenic compounds. Fractionation methods reported in the literature are reviewed according to three general schemas: (i) acid/base/neutral partitioning followed by fractionation using open-column chromatography and/or HPLC; (ii) fractionation based on normal-phase (NP) HPLC using a cyanopropyl or chemically similar stationary phase; and (iii) fractionation by open-column chromatography followed by NP-HPLC. The HPLC methods may be preparative, semi-preparative, or analytical scale. Variations based on acid/base/neutral partitioning followed by a chromatographic separation have also been employed. Other lesser-used approaches involve fractionation based on ion-exchange and thin-layer chromatographies. Although some of the methodologies used in contemporary studies of mutagenicity of air particulate do not represent significant advances in technology over the past 30 years, their simplicity, low

  19. Pesticides in honey: A review on chromatographic analytical methods.

    PubMed

    Tette, Patrícia Amaral Souza; Rocha Guidi, Letícia; Glória, Maria Beatriz de Abreu; Fernandes, Christian

    2016-01-01

    Honey is a product of high consumption due to its nutritional and antimicrobial properties. However, residues of pesticides, used in plagues' treatment in the hive or in crop fields in the neighborhoods, can compromise its quality. Therefore, determination of these contaminants in honey is essential, since the use of pesticides has increased significantly in recent decades because of the growing demand for food production. Furthermore, pesticides in honey can be an indicator of environmental contamination. As the concentration of these compounds in honey is usually at trace levels and several pesticides can be found simultaneously, the use of highly sensitive and selective techniques is required. In this context, miniaturized sample preparation approaches and liquid or gas chromatography coupled to mass spectrometry became the most important analytical techniques. In this review we present and discuss recent studies dealing with pesticide determination in honey, focusing on sample preparation and separation/detection methods as well as application of the developed methods worldwide. Furthermore, trends and future perspectives are presented. PMID:26717823

  20. An analytic reconstruction method for PET based on cubic splines

    NASA Astrophysics Data System (ADS)

    Kastis, George A.; Kyriakopoulou, Dimitra; Fokas, Athanasios S.

    2014-03-01

    PET imaging is an important nuclear medicine modality that measures in vivo distribution of imaging agents labeled with positron-emitting radionuclides. Image reconstruction is an essential component in tomographic medical imaging. In this study, we present the mathematical formulation and an improved numerical implementation of an analytic, 2D, reconstruction method called SRT, Spline Reconstruction Technique. This technique is based on the numerical evaluation of the Hilbert transform of the sinogram via an approximation in terms of 'custom made' cubic splines. It also imposes sinogram thresholding which restricts reconstruction only within object pixels. Furthermore, by utilizing certain symmetries it achieves a reconstruction time similar to that of FBP. We have implemented SRT in the software library called STIR and have evaluated this method using simulated PET data. We present reconstructed images from several phantoms. Sinograms have been generated at various Poison noise levels and 20 realizations of noise have been created at each level. In addition to visual comparisons of the reconstructed images, the contrast has been determined as a function of noise level. Further analysis includes the creation of line profiles when necessary, to determine resolution. Numerical simulations suggest that the SRT algorithm produces fast and accurate reconstructions at realistic noise levels. The contrast is over 95% in all phantoms examined and is independent of noise level.

  1. Pesticides in honey: A review on chromatographic analytical methods.

    PubMed

    Tette, Patrícia Amaral Souza; Rocha Guidi, Letícia; Glória, Maria Beatriz de Abreu; Fernandes, Christian

    2016-01-01

    Honey is a product of high consumption due to its nutritional and antimicrobial properties. However, residues of pesticides, used in plagues' treatment in the hive or in crop fields in the neighborhoods, can compromise its quality. Therefore, determination of these contaminants in honey is essential, since the use of pesticides has increased significantly in recent decades because of the growing demand for food production. Furthermore, pesticides in honey can be an indicator of environmental contamination. As the concentration of these compounds in honey is usually at trace levels and several pesticides can be found simultaneously, the use of highly sensitive and selective techniques is required. In this context, miniaturized sample preparation approaches and liquid or gas chromatography coupled to mass spectrometry became the most important analytical techniques. In this review we present and discuss recent studies dealing with pesticide determination in honey, focusing on sample preparation and separation/detection methods as well as application of the developed methods worldwide. Furthermore, trends and future perspectives are presented.

  2. Pyrrolizidine alkaloids in honey: comparison of analytical methods.

    PubMed

    Kempf, M; Wittig, M; Reinhard, A; von der Ohe, K; Blacquière, T; Raezke, K-P; Michel, R; Schreier, P; Beuerle, T

    2011-03-01

    Pyrrolizidine alkaloids (PAs) are a structurally diverse group of toxicologically relevant secondary plant metabolites. Currently, two analytical methods are used to determine PA content in honey. To achieve reasonably high sensitivity and selectivity, mass spectrometry detection is demanded. One method is an HPLC-ESI-MS-MS approach, the other a sum parameter method utilising HRGC-EI-MS operated in the selected ion monitoring mode (SIM). To date, no fully validated or standardised method exists to measure the PA content in honey. To establish an LC-MS method, several hundred standard pollen analysis results of raw honey were analysed. Possible PA plants were identified and typical commercially available marker PA-N-oxides (PANOs). Three distinct honey sets were analysed with both methods. Set A consisted of pure Echium honey (61-80% Echium pollen). Echium is an attractive bee plant. It is quite common in all temperate zones worldwide and is one of the major reasons for PA contamination in honey. Although only echimidine/echimidine-N-oxide were available as reference for the LC-MS target approach, the results for both analytical techniques matched very well (n = 8; PA content ranging from 311 to 520 µg kg(-1)). The second batch (B) consisted of a set of randomly picked raw honeys, mostly originating from Eupatorium spp. (0-15%), another common PA plant, usually characterised by the occurrence of lycopsamine-type PA. Again, the results showed good consistency in terms of PA-positive samples and quantification results (n = 8; ranging from 0 to 625 µg kg(-1) retronecine equivalents). The last set (C) was obtained by consciously placing beehives in areas with a high abundance of Jacobaea vulgaris (ragwort) from the Veluwe region (the Netherlands). J. vulgaris increasingly invades countrysides in Central Europe, especially areas with reduced farming or sites with natural restorations. Honey from two seasons (2007 and 2008) was sampled. While only trace amounts of

  3. DEMONSTRATION OF THE ANALYTIC ELEMENT METHOD FOR WELLHEAD PROTECTION

    EPA Science Inventory

    A new computer program has been developed to determine time-of-travel capture zones in relatively simple geohydrological settings. The WhAEM package contains an analytic element model that uses superposition of (many) closed form analytical solutions to generate a ground-water fl...

  4. Advanced Analysis Methods in High Energy Physics

    SciTech Connect

    Pushpalatha C. Bhat

    2001-10-03

    During the coming decade, high energy physics experiments at the Fermilab Tevatron and around the globe will use very sophisticated equipment to record unprecedented amounts of data in the hope of making major discoveries that may unravel some of Nature's deepest mysteries. The discovery of the Higgs boson and signals of new physics may be around the corner. The use of advanced analysis techniques will be crucial in achieving these goals. The author discusses some of the novel methods of analysis that could prove to be particularly valuable for finding evidence of any new physics, for improving precision measurements and for exploring parameter spaces of theoretical models.

  5. An analytical filter design method for guided wave phased arrays

    NASA Astrophysics Data System (ADS)

    Kwon, Hyu-Sang; Kim, Jin-Yeon

    2016-12-01

    This paper presents an analytical method for designing a spatial filter that processes the data from an array of two-dimensional guided wave transducers. An inverse problem is defined where the spatial filter coefficients are determined in such a way that a prescribed beam shape, i.e., a desired array output is best approximated in the least-squares sense. Taking advantage of the 2π-periodicity of the generated wave field, Fourier-series representation is used to derive closed-form expressions for the constituting matrix elements. Special cases in which the desired array output is an ideal delta function and a gate function are considered in a more explicit way. Numerical simulations are performed to examine the performance of the filters designed by the proposed method. It is shown that the proposed filters can significantly improve the beam quality in general. Most notable is that the proposed method does not compromise between the main lobe width and the sidelobe levels; i.e. a narrow main lobe and low sidelobes are simultaneously achieved. It is also shown that the proposed filter can compensate the effects of nonuniform directivity and sensitivity of array elements by explicitly taking these into account in the formulation. From an example of detecting two separate targets, how much the angular resolution can be improved as compared to the conventional delay-and-sum filter is quantitatively illustrated. Lamb wave based imaging of localized defects in an elastic plate using a circular array is also presented as an example of practical applications.

  6. Analytical method to estimate resin cement diffusion into dentin

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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.

  8. Analytical method to estimate resin cement diffusion into dentin

    NASA Astrophysics Data System (ADS)

    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.

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

    SciTech Connect

    Not Available

    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.

  10. Integrating Organic Matter Structure with Ecosystem Function using Advanced Analytical Chemistry Techniques

    NASA Astrophysics Data System (ADS)

    Boot, C. M.

    2012-12-01

    Microorganisms are the primary transformers of organic matter in terrestrial and aquatic ecosystems. The structure of organic matter controls its bioavailability and researchers have long sought to link the chemical characteristics of the organic matter pool to its lability. To date this effort has been primarily attempted using low resolution descriptive characteristics (e.g. organic matter content, carbon to nitrogen ratio, aromaticity, etc .). However, recent progress in linking these two important ecosystem components has been advanced using advanced high resolution tools (e.g. nuclear magnetic resonance (NMR) spectroscopy, and mass spectroscopy (MS)-based techniques). A series of experiments will be presented that highlight the application of high resolution techniques in a variety of terrestrial and aquatic ecosystems with the focus on how these data explicitly provide the foundation for integrating organic matter structure into our concept of ecosystem function. The talk will highlight results from a series of experiments including: an MS-based metabolomics and fluorescence excitation emission matrix approach evaluating seasonal and vegetation based changes in dissolved organic matter (DOM) composition from arctic soils; Fourier transform ion cyclotron resonance (FTICR) MS and MS metabolomics analysis of DOM from three lakes in an alpine watershed; and the transformation of 13C labeled glucose track with NMR during a rewetting experiment from Colorado grassland soils. These data will be synthesized to illustrate how the application of advanced analytical techniques provides novel insight into our understanding of organic matter processing in a wide range of ecosystems.

  11. Advanced reactor physics methods for heterogeneous reactor cores

    NASA Astrophysics Data System (ADS)

    Thompson, Steven A.

    To maintain the economic viability of nuclear power the industry has begun to emphasize maximizing the efficiency and output of existing nuclear power plants by using longer fuel cycles, stretch power uprates, shorter outage lengths, mixed-oxide (MOX) fuel and more aggressive operating strategies. In order to accommodate these changes, while still satisfying the peaking factor and power envelope requirements necessary to maintain safe operation, more complexity in commercial core designs have been implemented, such as an increase in the number of sub-batches and an increase in the use of both discrete and integral burnable poisons. A consequence of the increased complexity of core designs, as well as the use of MOX fuel, is an increase in the neutronic heterogeneity of the core. Such heterogeneous cores introduce challenges for the current methods that are used for reactor analysis. New methods must be developed to address these deficiencies while still maintaining the computational efficiency of existing reactor analysis methods. In this thesis, advanced core design methodologies are developed to be able to adequately analyze the highly heterogeneous core designs which are currently in use in commercial power reactors. These methodological improvements are being pursued with the goal of not sacrificing the computational efficiency which core designers require. More specifically, the PSU nodal code NEM is being updated to include an SP3 solution option, an advanced transverse leakage option, and a semi-analytical NEM solution option.

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

    SciTech Connect

    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

    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.

  13. Advances in plant gene silencing methods.

    PubMed

    Pandey, Prachi; Senthil-Kumar, Muthappa; Mysore, Kirankumar S

    2015-01-01

    Understanding molecular mechanisms of transcriptional and posttranscriptional gene silencing pathways in plants over the past decades has led to development of tools and methods for silencing a target gene in various plant species. In this review chapter, both the recent understanding of molecular basis of gene silencing pathways and advances in various widely used gene silencing methods are compiled. We also discuss the salient features of the different methods like RNA interference (RNAi) and virus-induced gene silencing (VIGS) and highlight their advantages and disadvantages. Gene silencing technology is constantly progressing as reflected by rapidly emerging new methods. A succinct discussion on the recently developed methods like microRNA-mediated virus-induced gene silencing (MIR-VIGS) and microRNA-induced gene silencing (MIGS) is also provided. One major bottleneck in gene silencing approaches has been the associated off-target silencing. The other hurdle has been the lack of a universal approach that can be applied to all plants. For example, we face hurdles like incompatibility of VIGS vectors with the host and inability to use MIGS for plant species which are not easily transformable. However, the overwhelming research in this direction reflects the scope for overcoming the short comings of gene silencing technology.

  14. Analytical methods in untargeted metabolomics: state of the art in 2015.

    PubMed

    Alonso, Arnald; Marsal, Sara; Julià, Antonio

    2015-01-01

    Metabolomics comprises the methods and techniques that are used to measure the small molecule composition of biofluids and tissues, and is actually one of the most rapidly evolving research fields. The determination of the metabolomic profile - the metabolome - has multiple applications in many biological sciences, including the developing of new diagnostic tools in medicine. Recent technological advances in nuclear magnetic resonance and mass spectrometry are significantly improving our capacity to obtain more data from each biological sample. Consequently, there is a need for fast and accurate statistical and bioinformatic tools that can deal with the complexity and volume of the data generated in metabolomic studies. In this review, we provide an update of the most commonly used analytical methods in metabolomics, starting from raw data processing and ending with pathway analysis and biomarker identification. Finally, the integration of metabolomic profiles with molecular data from other high-throughput biotechnologies is also reviewed.

  15. Analytical Methods in Untargeted Metabolomics: State of the Art in 2015

    PubMed Central

    Alonso, Arnald; Marsal, Sara; Julià, Antonio

    2015-01-01

    Metabolomics comprises the methods and techniques that are used to measure the small molecule composition of biofluids and tissues, and is actually one of the most rapidly evolving research fields. The determination of the metabolomic profile – the metabolome – has multiple applications in many biological sciences, including the developing of new diagnostic tools in medicine. Recent technological advances in nuclear magnetic resonance and mass spectrometry are significantly improving our capacity to obtain more data from each biological sample. Consequently, there is a need for fast and accurate statistical and bioinformatic tools that can deal with the complexity and volume of the data generated in metabolomic studies. In this review, we provide an update of the most commonly used analytical methods in metabolomics, starting from raw data processing and ending with pathway analysis and biomarker identification. Finally, the integration of metabolomic profiles with molecular data from other high-throughput biotechnologies is also reviewed. PMID:25798438

  16. The Mosquito Online Advanced Analytic Service: a case study for school research projects in Thailand.

    PubMed

    Wongkoon, Siriwan; Jaroensutasinee, Mullica; Jaroensutasinee, Krisanadej

    2013-07-01

    The Mosquito Online Advanced Analytic Service (MOAAS) provides an essential tool for querying, analyzing, and visualizing patterns of mosquito larval distribution in Thailand. The MOAAS was developed using Structured Query Language (SQL) technology as a web-based tool for data entry and data access, webMathematica technology for data analysis and data visualization, and Google Earth and Google Maps for Geographic Information System (GIS) visualization. Fifteen selected schools in Thailand provided test data for MOAAS. Users performed data entry using the web-service, data analysis, and data visualization tools with webMathematica, data visualization with bar charts, mosquito larval indices, and three-dimensional (3D) bar charts overlaying on the Google Earth and Google Maps. The 3D bar charts of the number of mosquito larvae were displayed along with spatial information. The mosquito larvae information may be useful for dengue control efforts and health service communities for planning and operational activities.

  17. The Mosquito Online Advanced Analytic Service: a case study for school research projects in Thailand.

    PubMed

    Wongkoon, Siriwan; Jaroensutasinee, Mullica; Jaroensutasinee, Krisanadej

    2013-07-01

    The Mosquito Online Advanced Analytic Service (MOAAS) provides an essential tool for querying, analyzing, and visualizing patterns of mosquito larval distribution in Thailand. The MOAAS was developed using Structured Query Language (SQL) technology as a web-based tool for data entry and data access, webMathematica technology for data analysis and data visualization, and Google Earth and Google Maps for Geographic Information System (GIS) visualization. Fifteen selected schools in Thailand provided test data for MOAAS. Users performed data entry using the web-service, data analysis, and data visualization tools with webMathematica, data visualization with bar charts, mosquito larval indices, and three-dimensional (3D) bar charts overlaying on the Google Earth and Google Maps. The 3D bar charts of the number of mosquito larvae were displayed along with spatial information. The mosquito larvae information may be useful for dengue control efforts and health service communities for planning and operational activities. PMID:24050090

  18. Big data, advanced analytics and the future of comparative effectiveness research.

    PubMed

    Berger, Marc L; Doban, Vitalii

    2014-03-01

    The intense competition that accompanied the growth of internet-based companies ushered in the era of 'big data' characterized by major innovations in processing of very large amounts of data and the application of advanced analytics including data mining and machine learning. Healthcare is on the cusp of its own era of big data, catalyzed by the changing regulatory and competitive environments, fueled by growing adoption of electronic health records, as well as efforts to integrate medical claims, electronic health records and other novel data sources. Applying the lessons from big data pioneers will require healthcare and life science organizations to make investments in new hardware and software, as well as in individuals with different skills. For life science companies, this will impact the entire pharmaceutical value chain from early research to postcommercialization support. More generally, this will revolutionize comparative effectiveness research.

  19. Analytic Method to Estimate Particle Acceleration in Flux Ropes

    NASA Technical Reports Server (NTRS)

    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.

  20. GENETIC-BASED ANALYTICAL METHODS FOR BACTERIA AND FUNGI

    EPA Science Inventory

    In the past two decades, advances in high-throughput sequencing technologies have lead to a veritable explosion in the generation of nucleic acid sequence information (1). While these advances are illustrated most prominently by the successful sequencing of the human genome, they...

  1. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Choi, Jachoon; El-Sharawy, El-Budawy; Hashemi-Yeganeh, Shahrokh; Birtcher, Craig R.

    1990-01-01

    High- and low-frequency methods to analyze various radiation elements located on aerospace vehicles with combinations of conducting, nonconducting, and energy absorbing surfaces and interfaces. The focus was on developing fundamental concepts, techniques, and algorithms which would remove some of the present limitations in predicting radiation characteristics of antennas on complex aerospace vehicles. In order to accomplish this, the following subjects were examined: (1) the development of techniques for rigorous analysis of surface discontinuities of metallic and nonmetallic surfaces using the equivalent surface impedance concept and Green's function; (2) the effects of anisotropic material on antenna radiation patterns through the use of an equivalent surface impedance concept which is incorporated into the existing numerical electromagnetics computer codes; and (3) the fundamental concepts of precipitation static (P-Static), such as formulations and analytical models. A computer code was used to model the P-Static process on a simple structure. Measurement techniques were also developed to characterized the electrical properties at microwave frequencies. Samples of typical materials used in airframes were tested and the results are included.

  2. Quantifying hydrate solidification front advancing using method of characteristics

    NASA Astrophysics Data System (ADS)

    You, Kehua; DiCarlo, David; Flemings, Peter B.

    2015-10-01

    We develop a one-dimensional analytical solution based on the method of characteristics to explore hydrate formation from gas injection into brine-saturated sediments within the hydrate stability zone. Our solution includes fully coupled multiphase and multicomponent flow and the associated advective transport in a homogeneous system. Our solution shows that hydrate saturation is controlled by the initial thermodynamic state of the system and changed by the gas fractional flow. Hydrate saturation in gas-rich systems can be estimated by 1-cl0/cle when Darcy flow dominates, where cl0 is the initial mass fraction of salt in brine, and cle is the mass fraction of salt in brine at three-phase (gas, liquid, and hydrate) equilibrium. Hydrate saturation is constant, gas saturation and gas flux decrease, and liquid saturation and liquid flux increase with the distance from the gas inlet to the hydrate solidification front. The total gas and liquid flux is constant from the gas inlet to the hydrate solidification front and decreases abruptly at the hydrate solidification front due to gas inclusion into the hydrate phase. The advancing velocity of the hydrate solidification front decreases with hydrate saturation at a fixed gas inflow rate. This analytical solution illuminates how hydrate is formed by gas injection (methane, CO2, ethane, propane) at both the laboratory and field scales.

  3. 40 CFR 136.6 - Method modifications and analytical requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... parameter that may be comprised of a number of substances. Examples of such analytes include temperature... requirements of paragraph (b)(2) of this section are met. (ii) If the characteristics of a wastewater matrix... must be dechlorinated prior to the addition of such salts. (iii) If the......

  4. An analytical method for the measurement of nonviable bioaerosols.

    PubMed

    Menetrez, M Y; Foarde, K K; Ensor, D S

    2001-10-01

    Exposures from indoor environments are a major issue for evaluating total long-term personal exposures to the fine fraction (<2.5 microm in aerodynamic diameter) of particulate matter (PM). It is widely accepted in the indoor air quality (IAQ) research community that biocontamination is one of the important indoor air pollutants. Major indoor air biocontaminants include mold, bacteria, dust mites, and other antigens. Once the biocontaminants or their metabolites become airborne, IAQ could be significantly deteriorated. The airborne biocontaminants or their metabolites can induce irritational, allergic, infectious, and chemical responses in exposed individuals. Biocontaminants, such as some mold spores or pollen grains, because of their size and mass, settle rapidly within the indoor environment. Over time they may become nonviable and fragmented by the process of desiccation. Desiccated nonviable fragments of organisms are common and can be toxic or allergenic, depending upon the specific organism or organism component. Once these smaller and lighter fragments of biological PM become suspended in air, they have a greater tendency to stay suspended. Although some bioaerosols have been identified, few have been quantitatively studied for their prevalence within the total indoor PM with time, or for their affinity to penetrate indoors. This paper describes a preliminary research effort to develop a methodology for the measurement of nonviable biologically based PM, analyzing for mold and ragweed antigens and endotoxins. The research objectives include the development of a set of analytical methods and the comparison of impactor media and sample size, and the quantification of the relationship between outdoor and indoor levels of bioaerosols. Indoor and outdoor air samples were passed through an Andersen nonviable cascade impactor in which particles from 0.2 to 9.0 microm were collected and analyzed. The presence of mold, ragweed, and endotoxin was found in all eight

  5. Laser: a Tool for Optimization and Enhancement of Analytical Methods

    SciTech Connect

    Preisler, Jan

    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

  6. Putting synchrotron radiation to work for technology: Analytic methods

    SciTech Connect

    Not Available

    1992-02-01

    This report contains viewgraphs on: Advanced Light Source; Ultra-ESCA: Advanced Capabilities of XPS with High-Brightness Synchrotron Radiation; High-Resolution (20 nm) XPS and XANES with the ALS; Photoelectron Spectroscopy in Industry: Current Capabilities, Needs, and Possible Roles for the ALS; Materials Analysis by Photoemission: Is This Practical at ALS?; Applications of Long-Wavelength X-Ray Fluorescence Spectrometry and X-Ray Powder Diffractometry.

  7. Putting synchrotron radiation to work for technology: Analytic methods

    SciTech Connect

    Not Available

    1992-02-01

    This report contains viewgraphs on: Advanced Light Source; Ultra-ESCA: Advanced Capabilities of XPS with High-Brightness Synchrotron Radiation; High-Resolution (20 nm) XPS and XANES with the ALS; Photoelectron Spectroscopy in Industry: Current Capabilities, Needs, and Possible Roles for the ALS; Materials Analysis by Photoemission: Is This Practical at ALS ; Applications of Long-Wavelength X-Ray Fluorescence Spectrometry and X-Ray Powder Diffractometry.

  8. A new and consistent parameter for measuring the quality of multivariate analytical methods: Generalized analytical sensitivity.

    PubMed

    Fragoso, Wallace; Allegrini, Franco; Olivieri, Alejandro C

    2016-08-24

    Generalized analytical sensitivity (γ) is proposed as a new figure of merit, which can be estimated from a multivariate calibration data set. It can be confidently applied to compare different calibration methodologies, and helps to solve literature inconsistencies on the relationship between classical sensitivity and prediction error. In contrast to the classical plain sensitivity, γ incorporates the noise properties in its definition, and its inverse is well correlated with root mean square errors of prediction in the presence of general noise structures. The proposal is supported by studying simulated and experimental first-order multivariate calibration systems with various models, namely multiple linear regression, principal component regression (PCR) and maximum likelihood PCR (MLPCR). The simulations included instrumental noise of different types: independently and identically distributed (iid), correlated (pink) and proportional noise, while the experimental data carried noise which is clearly non-iid. PMID:27496995

  9. A new and consistent parameter for measuring the quality of multivariate analytical methods: Generalized analytical sensitivity.

    PubMed

    Fragoso, Wallace; Allegrini, Franco; Olivieri, Alejandro C

    2016-08-24

    Generalized analytical sensitivity (γ) is proposed as a new figure of merit, which can be estimated from a multivariate calibration data set. It can be confidently applied to compare different calibration methodologies, and helps to solve literature inconsistencies on the relationship between classical sensitivity and prediction error. In contrast to the classical plain sensitivity, γ incorporates the noise properties in its definition, and its inverse is well correlated with root mean square errors of prediction in the presence of general noise structures. The proposal is supported by studying simulated and experimental first-order multivariate calibration systems with various models, namely multiple linear regression, principal component regression (PCR) and maximum likelihood PCR (MLPCR). The simulations included instrumental noise of different types: independently and identically distributed (iid), correlated (pink) and proportional noise, while the experimental data carried noise which is clearly non-iid.

  10. Advanced fault diagnosis methods in molecular networks.

    PubMed

    Habibi, Iman; Emamian, Effat S; Abdi, Ali

    2014-01-01

    Analysis of the failure of cell signaling networks is an important topic in systems biology and has applications in target discovery and drug development. In this paper, some advanced methods for fault diagnosis in signaling networks are developed and then applied to a caspase network and an SHP2 network. The goal is to understand how, and to what extent, the dysfunction of molecules in a network contributes to the failure of the entire network. Network dysfunction (failure) is defined as failure to produce the expected outputs in response to the input signals. Vulnerability level of a molecule is defined as the probability of the network failure, when the molecule is dysfunctional. In this study, a method to calculate the vulnerability level of single molecules for different combinations of input signals is developed. Furthermore, a more complex yet biologically meaningful method for calculating the multi-fault vulnerability levels is suggested, in which two or more molecules are simultaneously dysfunctional. Finally, a method is developed for fault diagnosis of networks based on a ternary logic model, which considers three activity levels for a molecule instead of the previously published binary logic model, and provides equations for the vulnerabilities of molecules in a ternary framework. Multi-fault analysis shows that the pairs of molecules with high vulnerability typically include a highly vulnerable molecule identified by the single fault analysis. The ternary fault analysis for the caspase network shows that predictions obtained using the more complex ternary model are about the same as the predictions of the simpler binary approach. This study suggests that by increasing the number of activity levels the complexity of the model grows; however, the predictive power of the ternary model does not appear to be increased proportionally.

  11. Extraction of effective parameters of anisotropic optical materials using a decoupled analytical method.

    PubMed

    Pham, Thi-Thu-Hien; Lo, Yu-Lung

    2012-02-01

    A decoupled analytical technique based on the Mueller matrix method and the Stokes parameters is proposed for extracting effective parameters of anisotropic optical materials in linear birefringence (LB), linear dichroism (LD), circular birefrinegence (CB), and circular dichroism (CD) properties. This technique is essential in determining the optical properties of opto-electric or biomedical materials for the development of advanced inspection and/or diagnostic applications. The error and resolution analysis of the proposed approach is demonstrated by extracting the effective parameters given an assumption of errors ranging ± 0.005 in the values of the output Stokes parameters. The results confirm the ability of the proposed method to yield full-range measurements of all the optical parameters. The decoupled nature of the analytical model yields several important advantages, including an improved accuracy and the ability to extract the parameters of optical samples with only LB, CB, LD, or CD property without using compensation technique or pretreatment. Moreover, by decoupling the extraction process, the "multiple solutions" problem inherent in previous models presented by the current group is avoided.

  12. Perinatal periods of risk: analytic preparation and phase 1 analytic methods for investigating feto-infant mortality.

    PubMed

    Sappenfield, William M; Peck, Magda G; Gilbert, Carol S; Haynatzka, Vera R; Bryant, Thomas

    2010-11-01

    The Perinatal Periods of Risk (PPOR) methods provide the necessary framework and tools for large urban communities to investigate feto-infant mortality problems. Adapted from the Periods of Risk model developed by Dr. Brian McCarthy, the six-stage PPOR approach includes epidemiologic methods to be used in conjunction with community planning processes. Stage 2 of the PPOR approach has three major analytic parts: Analytic Preparation, which involves acquiring, preparing, and assessing vital records files; Phase 1 Analysis, which identifies local opportunity gaps; and Phase 2 Analyses, which investigate the opportunity gaps to determine likely causes of feto-infant mortality and to suggest appropriate actions. This article describes the first two analytic parts of PPOR, including methods, innovative aspects, rationale, limitations, and a community example. In Analytic Preparation, study files are acquired and prepared and data quality is assessed. In Phase 1 Analysis, feto-infant mortality is estimated for four distinct perinatal risk periods defined by both birthweight and age at death. These mutually exclusive risk periods are labeled Maternal Health and Prematurity, Maternal Care, Newborn Care, and Infant Health to suggest primary areas of prevention. Disparities within the study community are identified by comparing geographic areas, subpopulations, and time periods. Excess mortality numbers and rates are estimated by comparing the study population to an optimal reference population. This excess mortality is described as the opportunity gap because it indicates where communities have the potential to make improvement.

  13. Application of nanotechnology in miniaturized systems and its use for advanced analytics and diagnostics - an updated review.

    PubMed

    Sandetskaya, Natalia; Allelein, Susann; Kuhlmeier, Dirk

    2013-12-01

    A combination of Micro-Electro-Mechanical Systems and nanoscale structures allows for the creation of novel miniaturized devices, which broaden the boundaries of the diagnostic approaches. Some materials possess unique properties at the nanolevel, which are different from those in bulk materials. In the last few years these properties became a focus of interest for many researchers, as well as methods of production, design and operation of the nanoobjects. Intensive research and development work resulted in numerous inventions exploiting nanotechnology in miniaturized systems. Modern technical and laboratory equipment allows for the precise control of such devices, making them suitable for sensitive and accurate detection of the analytes. The current review highlights recent patents in the field of nanotechnology in microdevices, applicable for medical, environmental or food analysis. The paper covers the structural and functional basis of such systems and describes specific embodiments in three principal branches: application of nanoparticles, nanofluidics, and nanosensors in the miniaturized systems for advanced analytics and diagnostics. This overview is an update of an earlier review article. PMID:24365338

  14. Application of nanotechnology in miniaturized systems and its use for advanced analytics and diagnostics - an updated review.

    PubMed

    Sandetskaya, Natalia; Allelein, Susann; Kuhlmeier, Dirk

    2013-12-01

    A combination of Micro-Electro-Mechanical Systems and nanoscale structures allows for the creation of novel miniaturized devices, which broaden the boundaries of the diagnostic approaches. Some materials possess unique properties at the nanolevel, which are different from those in bulk materials. In the last few years these properties became a focus of interest for many researchers, as well as methods of production, design and operation of the nanoobjects. Intensive research and development work resulted in numerous inventions exploiting nanotechnology in miniaturized systems. Modern technical and laboratory equipment allows for the precise control of such devices, making them suitable for sensitive and accurate detection of the analytes. The current review highlights recent patents in the field of nanotechnology in microdevices, applicable for medical, environmental or food analysis. The paper covers the structural and functional basis of such systems and describes specific embodiments in three principal branches: application of nanoparticles, nanofluidics, and nanosensors in the miniaturized systems for advanced analytics and diagnostics. This overview is an update of an earlier review article.

  15. Hanford environmental analytical methods: Methods as of March 1990. Volume 3, Appendix A2-I

    SciTech Connect

    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.

  16. Advanced superposition methods for high speed turbopump vibration analysis

    NASA Technical Reports Server (NTRS)

    Nielson, C. E.; Campany, A. D.

    1981-01-01

    The small, high pressure Mark 48 liquid hydrogen turbopump was analyzed and dynamically tested to determine the cause of high speed vibration at an operating speed of 92,400 rpm. This approaches the design point operating speed of 95,000 rpm. The initial dynamic analysis in the design stage and subsequent further analysis of the rotor only dynamics failed to predict the vibration characteristics found during testing. An advanced procedure for dynamics analysis was used in this investigation. The procedure involves developing accurate dynamic models of the rotor assembly and casing assembly by finite element analysis. The dynamically instrumented assemblies are independently rap tested to verify the analytical models. The verified models are then combined by modal superposition techniques to develop a completed turbopump model where dynamic characteristics are determined. The results of the dynamic testing and analysis obtained are presented and methods of moving the high speed vibration characteristics to speeds above the operating range are recommended. Recommendations for use of these advanced dynamic analysis procedures during initial design phases are given.

  17. Sonoluminescence Spectroscopy as a Promising New Analytical Method

    NASA Astrophysics Data System (ADS)

    Yurchenko, O. I.; Kalinenko, O. S.; Baklanov, A. N.; Belov, E. A.; Baklanova, L. V.

    2016-03-01

    The sonoluminescence intensity of Cs, Ru, K, Na, Li, Sr, In, Ga, Ca, Th, Cr, Pb, Mn, Ag, and Mg salts in aqueous solutions of various concentrations was investigated as a function of ultrasound frequency and intensity. Techniques for the determination of these elements in solutions of table salt and their own salts were developed. It was shown that the proposed analytical technique gave results at high concentrations with better metrological characteristics than atomic-absorption spectroscopy because the samples were not diluted.

  18. Method for Operating a Sensor to Differentiate Between Analytes in a Sample

    DOEpatents

    Kunt, Tekin; Cavicchi, Richard E; Semancik, Stephen; McAvoy, Thomas J

    1998-07-28

    Disclosed is a method for operating a sensor to differentiate between first and second analytes in a sample. The method comprises the steps of determining a input profile for the sensor which will enhance the difference in the output profiles of the sensor as between the first analyte and the second analyte; determining a first analyte output profile as observed when the input profile is applied to the sensor; determining a second analyte output profile as observed when the temperature profile is applied to the sensor; introducing the sensor to the sample while applying the temperature profile to the sensor, thereby obtaining a sample output profile; and evaluating the sample output profile as against the first and second analyte output profiles to thereby determine which of the analytes is present in the sample.

  19. parallelMCMCcombine: an R package for bayesian methods for big data and analytics.

    PubMed

    Miroshnikov, Alexey; Conlon, Erin M

    2014-01-01

    Recent advances in big data and analytics research have provided a wealth of large data sets that are too big to be analyzed in their entirety, due to restrictions on computer memory or storage size. New Bayesian methods have been developed for data sets that are large only due to large sample sizes. These methods partition big data sets into subsets and perform independent Bayesian Markov chain Monte Carlo analyses on the subsets. The methods then combine the independent subset posterior samples to estimate a posterior density given the full data set. These approaches were shown to be effective for Bayesian models including logistic regression models, Gaussian mixture models and hierarchical models. Here, we introduce the R package parallelMCMCcombine which carries out four of these techniques for combining independent subset posterior samples. We illustrate each of the methods using a Bayesian logistic regression model for simulation data and a Bayesian Gamma model for real data; we also demonstrate features and capabilities of the R package. The package assumes the user has carried out the Bayesian analysis and has produced the independent subposterior samples outside of the package. The methods are primarily suited to models with unknown parameters of fixed dimension that exist in continuous parameter spaces. We envision this tool will allow researchers to explore the various methods for their specific applications and will assist future progress in this rapidly developing field.

  20. Advanced continuous cultivation methods for systems microbiology.

    PubMed

    Adamberg, Kaarel; Valgepea, Kaspar; Vilu, Raivo

    2015-09-01

    Increasing the throughput of systems biology-based experimental characterization of in silico-designed strains has great potential for accelerating the development of cell factories. For this, analysis of metabolism in the steady state is essential as only this enables the unequivocal definition of the physiological state of cells, which is needed for the complete description and in silico reconstruction of their phenotypes. In this review, we show that for a systems microbiology approach, high-resolution characterization of metabolism in the steady state--growth space analysis (GSA)--can be achieved by using advanced continuous cultivation methods termed changestats. In changestats, an environmental parameter is continuously changed at a constant rate within one experiment whilst maintaining cells in the physiological steady state similar to chemostats. This increases the resolution and throughput of GSA compared with chemostats, and, moreover, enables following of the dynamics of metabolism and detection of metabolic switch-points and optimal growth conditions. We also describe the concept, challenge and necessary criteria of the systematic analysis of steady-state metabolism. Finally, we propose that such systematic characterization of the steady-state growth space of cells using changestats has value not only for fundamental studies of metabolism, but also for systems biology-based metabolic engineering of cell factories.

  1. Advanced electromagnetic methods for aerospace vehicles

    NASA Astrophysics Data System (ADS)

    Balanis, Constantine A.; Sun, Weimin; El-Sharawy, El-Budawy; Aberle, James T.; Birtcher, Craig R.; Peng, Jian; Tirkas, Panayiotis A.; Kokotoff, David; Zavosh, Frank

    1993-06-01

    The Advanced Helicopter Electromagnetics (AHE) Industrial Associates Program has continuously progressed with its research effort focused on subjects identified and recommended by the Advisory Task Force of the program. The research activities in this reporting period have been steered toward practical helicopter electromagnetic problems, such as HF antenna problems and antenna efficiencies, recommended by the AHE members at the annual conference held at Arizona State University on 28-29 Oct. 1992 and the last biannual meeting held at the Boeing Helicopter on 19-20 May 1993. The main topics addressed include the following: Composite Materials and Antenna Technology. The research work on each topic is closely tied with the AHE Consortium members' interests. Significant progress in each subject is reported. Special attention in the area of Composite Materials has been given to the following: modeling of material discontinuity and their effects on towel-bar antenna patterns; guidelines for composite material modeling by using the Green's function approach in the NEC code; measurements of towel-bar antennas grounded with a partially material-coated plate; development of 3-D volume mesh generator for modeling thick and volumetric dielectrics by using FD-TD method; FDTD modeling of horn antennas with composite E-plane walls; and antenna efficiency analysis for a horn antenna loaded with composite dielectric materials.

  2. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Sun, Weimin; El-Sharawy, El-Budawy; Aberle, James T.; Birtcher, Craig R.; Peng, Jian; Tirkas, Panayiotis A.; Kokotoff, David; Zavosh, Frank

    1993-01-01

    The Advanced Helicopter Electromagnetics (AHE) Industrial Associates Program has continuously progressed with its research effort focused on subjects identified and recommended by the Advisory Task Force of the program. The research activities in this reporting period have been steered toward practical helicopter electromagnetic problems, such as HF antenna problems and antenna efficiencies, recommended by the AHE members at the annual conference held at Arizona State University on 28-29 Oct. 1992 and the last biannual meeting held at the Boeing Helicopter on 19-20 May 1993. The main topics addressed include the following: Composite Materials and Antenna Technology. The research work on each topic is closely tied with the AHE Consortium members' interests. Significant progress in each subject is reported. Special attention in the area of Composite Materials has been given to the following: modeling of material discontinuity and their effects on towel-bar antenna patterns; guidelines for composite material modeling by using the Green's function approach in the NEC code; measurements of towel-bar antennas grounded with a partially material-coated plate; development of 3-D volume mesh generator for modeling thick and volumetric dielectrics by using FD-TD method; FDTD modeling of horn antennas with composite E-plane walls; and antenna efficiency analysis for a horn antenna loaded with composite dielectric materials.

  3. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Sun, Weimin; El-Sharawy, El-Budawy; Aberle, James T.; Birtcher, Craig R.; Peng, Jian; Tirkas, Panayiotis A.; Andrew, William V.; Kokotoff, David; Zavosh, Frank

    1993-01-01

    The Advanced Helicopter Electromagnetics (AHE) Industrial Associates Program has fruitfully completed its fourth year. Under the support of the AHE members and the joint effort of the research team, new and significant progress has been achieved in the year. Following the recommendations by the Advisory Task Force, the research effort is placed on more practical helicopter electromagnetic problems, such as HF antennas, composite materials, and antenna efficiencies. In this annual report, the main topics to be addressed include composite materials and antenna technology. The research work on each topic has been driven by the AHE consortium members' interests and needs. The remarkable achievements and progresses in each subject is reported respectively in individual sections of the report. The work in the area of composite materials includes: modeling of low conductivity composite materials by using Green's function approach; guidelines for composite material modeling by using the Green's function approach in the NEC code; development of 3-D volume mesh generator for modeling thick and volumetric dielectrics by using FD-TD method; modeling antenna elements mounted on a composite Comanche tail stabilizer; and antenna pattern control and efficiency estimate for a horn antenna loaded with composite dielectric materials.

  4. Analytical and experimental evaluation of joining silicon nitride to metal and silicon carbide to metal for advanced heat engine applications

    SciTech Connect

    Kang, S.; Selverian, J.H.; Kim, H.; O'Niel, D.; Kim, K. )

    1990-04-01

    This report summarizes the results of Phase I of Analytical and Experimental Evaluation of Joining Silicon Nitride to Metal and Silicon Carbide to Metal and Silicon Carbide to Metal for Advanced Heat Engine Applications. A general methodology was developed to optimize the joint geometry and material systems for 650 and 950{degree}C applications. Failure criteria were derived to predict the fracture of the braze and ceramic. Extensive finite element analyses (FEA), using ABAQUS code, were performed to examine various joint geometries and to evaluate the affect of different interlayers on the residual stress state. Also, material systems composed of coating materials, interlayers, and braze alloys were developed for the program based on the chemical stability and strength of the joints during processing and service. Finally, the FEA results were compared with experiments using an idealized strength relationship. The results showed that the measured strength of the joint reached 30--90% of the strength by predicted by FEA. Overall results demonstrated that FEA is an effective tool for designing the geometries of ceramic-metal joints and that joining by brazing is a relevant method for advanced heat engine applications. 33 refs., 54 figs., 36 tabs.

  5. An Advanced Analytical Chemistry Experiment Using Gas Chromatography-Mass Spectrometry, MATLAB, and Chemometrics to Predict Biodiesel Blend Percent Composition

    ERIC Educational Resources Information Center

    Pierce, Karisa M.; Schale, Stephen P.; Le, Trang M.; Larson, Joel C.

    2011-01-01

    We present a laboratory experiment for an advanced analytical chemistry course where we first focus on the chemometric technique partial least-squares (PLS) analysis applied to one-dimensional (1D) total-ion-current gas chromatography-mass spectrometry (GC-TIC) separations of biodiesel blends. Then, we focus on n-way PLS (n-PLS) applied to…

  6. Knowledge Style Profiling: An Exploration of Cognitive, Temperament, Demographic and Organizational Characteristics among Decision Makers Using Advanced Analytical Technologies

    ERIC Educational Resources Information Center

    Polito, Vincent A., Jr.

    2010-01-01

    The objective of this research was to explore the possibilities of identifying knowledge style factors that could be used as central elements of a professional business analyst's (PBA) performance attributes at work for those decision makers that use advanced analytical technologies on decision making tasks. Indicators of knowledge style were…

  7. 40 CFR 141.852 - Analytical methods and laboratory certification.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Standard Methods Online 9221 B.1, B.2-99 2 3 Presence-Absence (P-A) Coliform Test Standard Methods 9221 D.1... Method 1604 2 m-ColiBlue24® Test 2 4 Chromocult 2 4 Enzyme Substrate Methods Colilert® Standard Methods... MI mediumm-ColiBlue24® Test 2,4 EPA Method 1604 2 Chromocult 2 4 Enzyme Substrate Methods...

  8. Identifying factors that impact patient length of stay metrics for healthcare providers with advanced analytics.

    PubMed

    Kudyba, Stephan; Gregorio, Thomas

    2010-12-01

    Managing patients' length of stay is a critical task for healthcare organizations. In order to better manage the processes impacting this performance metric, providers can leverage data resources describing the network of activities that impact a patient's stay with analytic methods. Interdependencies between departmental activities exist within the patient treatment process, where inefficiency in one element of the patient care network of activities can adversely affect process outcomes.This work utilizes the method of neural networks to analyze data describing inpatient cases that incorporate radiology process variables to determine their effect on patient length of stay excesses for a major NJ based healthcare provider. The results indicate that inefficiencies at the radiology level can adversely extend a patient's length of stay beyond initial estimations. Proactive analysis of networks of activities in the patient treatment process can enhance organizational efficiencies of healthcare providers by enabling decision makers to better optimize resource allocations to increase throughput of activities.

  9. AALIM: a cardiac clinical decision support system powered by advanced multi-modal analytics.

    PubMed

    Amir, Arnon; Beymer, David; Grace, Julia; Greenspan, Hayit; Gruhl, Daniel; Hobbs, Allen; Pohl, Kilian; Syeda-Mahmood, Tanveer; Terdiman, Joseph; Wang, Fei

    2010-01-01

    Modern Electronic Medical Record (EMR) systems often integrate large amounts of data from multiple disparate sources. To do so, EMR systems must align the data to create consistency between these sources. The data should also be presented in a manner that allows a clinician to quickly understand the complete condition and history of a patient's health. We develop the AALIM system to address these issues using advanced multimodal analytics. First, it extracts and computes multiple features and cues from the patient records and medical tests. This additional metadata facilitates more accurate alignment of the various modalities, enables consistency check and empowers a clear, concise presentation of the patient's complete health information. The system further provides a multimodal search for similar cases within the EMR system, and derives related conditions and drugs information from them. We applied our approach to cardiac data from a major medical care organization and found that it produced results with sufficient quality to assist the clinician making appropriate clinical decisions.

  10. PESTICIDE ANALYTICAL METHODS TO SUPPORT DUPLICATE-DIET HUMAN EXPOSURE MEASUREMENTS

    EPA Science Inventory

    Historically, analytical methods for determination of pesticides in foods have been developed in support of regulatory programs and are specific to food items or food groups. Most of the available methods have been developed, tested and validated for relatively few analytes an...

  11. 40 CFR 141.852 - Analytical methods and laboratory certification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Standard Methods Online 9221 B.1, B.2-99.2 3 Presence-Absence (P-A) Coliform Test Standard Methods 9221 D.1...-ColiBlue24® Test 2 4 Chromocult 2 4 Enzyme Substrate Methods Colilert® Standard Methods 9223 B (20th ed...-ColiBlue24® Test 2 4 EPA Method 1604 2 Chromocult 2 4 Enzyme Substrate Methods Colilert®...

  12. Validation of analytical methods involved in dissolution assays: acceptance limits and decision methodologies.

    PubMed

    Rozet, E; Ziemons, E; Marini, R D; Boulanger, B; Hubert, Ph

    2012-11-01

    Dissolution tests are key elements to ensure continuing product quality and performance. The ultimate goal of these tests is to assure consistent product quality within a defined set of specification criteria. Validation of an analytical method aimed at assessing the dissolution profile of products or at verifying pharmacopoeias compliance should demonstrate that this analytical method is able to correctly declare two dissolution profiles as similar or drug products as compliant with respect to their specifications. It is essential to ensure that these analytical methods are fit for their purpose. Method validation is aimed at providing this guarantee. However, even in the ICHQ2 guideline there is no information explaining how to decide whether the method under validation is valid for its final purpose or not. Are the entire validation criterion needed to ensure that a Quality Control (QC) analytical method for dissolution test is valid? What acceptance limits should be set on these criteria? How to decide about method's validity? These are the questions that this work aims at answering. Focus is made to comply with the current implementation of the Quality by Design (QbD) principles in the pharmaceutical industry in order to allow to correctly defining the Analytical Target Profile (ATP) of analytical methods involved in dissolution tests. Analytical method validation is then the natural demonstration that the developed methods are fit for their intended purpose and is not any more the inconsiderate checklist validation approach still generally performed to complete the filing required to obtain product marketing authorization. PMID:23084050

  13. DEMONSTRATION BULLETIN: FIELD ANALYTICAL SCREENING PROGRAM: PCB METHOD - U.S. ENVIRONMENTAL PROTECTION AGENCY

    EPA Science Inventory

    The field analytical screening program (FASP) polychlorinated biphenyl (PCB) method uses a temperature-programmable gas chromatograph (GC) equipped with an electron capture detector (ECD) to identify and quantify PCBs. Gas chromatography is an EPA-approved method for determi...

  14. Analytical methods for the determination of carbon tetrachloride in soils.

    SciTech Connect

    Alvarado, J. S.; Spokas, K.; Taylor, J.

    1999-06-01

    Improved methods for the determination of carbon tetrachloride are described. These methods incorporate purge-and-trap concentration of heated dry samples, an improved methanol extraction procedure, and headspace sampling. The methods minimize sample pretreatment, accomplish solvent substitution, and save time. The methanol extraction and headspace sampling procedures improved the method detection limits and yielded better sensitivity, good recoveries, and good performance. Optimization parameters are shown. Results obtained with these techniques are compared for soil samples from contaminated sites.

  15. A versatile, quantitative analytical method for pharmaceutical relevant lipids in drug delivery systems.

    PubMed

    Jeschek, Dominik; Lhota, Gabriele; Wallner, Jakob; Vorauer-Uhl, Karola

    2016-02-01

    Over the past few years, liposomal formulations as drug carrier systems have markedly advanced in pharmaceutical research and development. Therefore, analytical methods to characterize liposome-based formulations are required. One particular issue in liposome analysis is the imbalance of lipid ratios within the vesicle formulations and the detectability of degradation products such as lysophospholipids and fatty acids caused by hydrolysis, especially in low molar ranges. Here, a highly sensitive and selective reversed-phase high-performance liquid chromatography (rp-HPLC) method is described by the combination of an organic solvent/trifluoroacetic acid (TFA) triggered gradient and the application of an evaporative light scattering detector (ELSD). Gain setting adjustments of the ELSD were applied to obtain an optimal detection profile of the analyzed substances. This optimization provides simultaneous separation and quantification of 16 components, including different phosphatidylcholines, phosphatidylglycerols and their degradation products, as well as cholesterol. Parameters such as limit of detection (LOD) and limit of quantification (LOQ) were determined for each of the components and had ranges from 0.25-1.00mg/mL (LOD) and 0.50-2.50μg/mL (LOQ), respectively. The intra-day precision for all analytes is less than 3% (RSD) and inter-day precision is about 8%. The applicability of the method was verified by analyzing two different liposome formulations consisting of DSPC:DPPC:DSPG:Chol (35:35:20:10) and DSPC:DPPC:DSPG (38:38:24). For degradation studies, both formulations were stored at 4°C and at ambient temperature. Additionally, forced degradation experiments were performed to determine hydrolysis mass balances. A total recovery of 96-102% for phospholipid compounds was found. Analytical data revealed that the sensitivity, selectivity, accuracy, and resolution are appropriate for the detection and quantification of phospholipids and their hydrolysis products

  16. A versatile, quantitative analytical method for pharmaceutical relevant lipids in drug delivery systems.

    PubMed

    Jeschek, Dominik; Lhota, Gabriele; Wallner, Jakob; Vorauer-Uhl, Karola

    2016-02-01

    Over the past few years, liposomal formulations as drug carrier systems have markedly advanced in pharmaceutical research and development. Therefore, analytical methods to characterize liposome-based formulations are required. One particular issue in liposome analysis is the imbalance of lipid ratios within the vesicle formulations and the detectability of degradation products such as lysophospholipids and fatty acids caused by hydrolysis, especially in low molar ranges. Here, a highly sensitive and selective reversed-phase high-performance liquid chromatography (rp-HPLC) method is described by the combination of an organic solvent/trifluoroacetic acid (TFA) triggered gradient and the application of an evaporative light scattering detector (ELSD). Gain setting adjustments of the ELSD were applied to obtain an optimal detection profile of the analyzed substances. This optimization provides simultaneous separation and quantification of 16 components, including different phosphatidylcholines, phosphatidylglycerols and their degradation products, as well as cholesterol. Parameters such as limit of detection (LOD) and limit of quantification (LOQ) were determined for each of the components and had ranges from 0.25-1.00mg/mL (LOD) and 0.50-2.50μg/mL (LOQ), respectively. The intra-day precision for all analytes is less than 3% (RSD) and inter-day precision is about 8%. The applicability of the method was verified by analyzing two different liposome formulations consisting of DSPC:DPPC:DSPG:Chol (35:35:20:10) and DSPC:DPPC:DSPG (38:38:24). For degradation studies, both formulations were stored at 4°C and at ambient temperature. Additionally, forced degradation experiments were performed to determine hydrolysis mass balances. A total recovery of 96-102% for phospholipid compounds was found. Analytical data revealed that the sensitivity, selectivity, accuracy, and resolution are appropriate for the detection and quantification of phospholipids and their hydrolysis products

  17. Why Video? How Technology Advances Method

    ERIC Educational Resources Information Center

    Downing, Martin J., Jr.

    2008-01-01

    This paper reports on the use of video to enhance qualitative research. Advances in technology have improved our ability to capture lived experiences through visual means. I reflect on my previous work with individuals living with HIV/AIDS, the results of which are described in another paper, to evaluate the effectiveness of video as a medium that…

  18. Advances in the analytical methodologies: Profiling steroids in familiar pathways-challenging dogmas.

    PubMed

    Bloem, Liezl M; Storbeck, Karl-Heinz; Swart, Pieter; du Toit, Therina; Schloms, Lindie; Swart, Amanda C

    2015-09-01

    . Undoubtedly, the continuous advances in the analytical methodologies used for steroid profiling and quantification will give impetus to the unraveling of the remaining enigmas, old and new, of both hormone biosynthesis and metabolism.

  19. Analytical methods for determination of mycotoxins: An update (2009-2014).

    PubMed

    Turner, Nicholas W; Bramhmbhatt, Heli; Szabo-Vezse, Monika; Poma, Alessandro; Coker, Raymond; Piletsky, Sergey A

    2015-12-11

    Mycotoxins are a problematic and toxic group of small organic molecules that are produced as secondary metabolites by several fungal species that colonise crops. They lead to contamination at both the field and postharvest stages of food production with a considerable range of foodstuffs affected, from coffee and cereals, to dried fruit and spices. With wide ranging structural diversity of mycotoxins, severe toxic effects caused by these molecules and their high chemical stability the requirement for robust and effective detection methods is clear. This paper builds on our previous review and summarises the most recent advances in this field, in the years 2009-2014 inclusive. This review summarises traditional methods such as chromatographic and immunochemical techniques, as well as newer approaches such as biosensors, and optical techniques which are becoming more prevalent. A section on sampling and sample treatment has been prepared to highlight the importance of this step in the analytical methods. We close with a look at emerging technologies that will bring effective and rapid analysis out of the laboratory and into the field.

  20. Team mental models: techniques, methods, and analytic approaches.

    PubMed

    Langan-Fox, J; Code, S; Langfield-Smith, K

    2000-01-01

    Effective team functioning requires the existence of a shared or team mental model among members of a team. However, the best method for measuring team mental models is unclear. Methods reported vary in terms of how mental model content is elicited and analyzed or represented. We review the strengths and weaknesses of vatrious methods that have been used to elicit, represent, and analyze individual and team mental models and provide recommendations for method selection and development. We describe the nature of mental models and review techniques that have been used to elicit and represent them. We focus on a case study on selecting a method to examine team mental models in industry. The processes involved in the selection and development of an appropriate method for eliciting, representing, and analyzing team mental models are described. The criteria for method selection were (a) applicability to the problem under investigation; (b) practical considerations - suitability for collecting data from the targeted research sample; and (c) theoretical rationale - the assumption that associative networks in memory are a basis for the development of mental models. We provide an evaluation of the method matched to the research problem and make recommendations for future research. The practical applications of this research include the provision of a technique for analyzing team mental models in organizations, the development of methods and processes for eliciting a mental model from research participants in their normal work environment, and a survey of available methodologies for mental model research.

  1. Application of an analytical method for solution of thermal hydraulic conservation equations

    SciTech Connect

    Fakory, M.R.

    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.

  2. Tank 48H Waste Composition and Results of Investigation of Analytical Methods

    SciTech Connect

    Walker , D.D.

    1997-04-02

    This report serves two purposes. First, it documents the analytical results of Tank 48H samples taken between April and August 1996. Second, it describes investigations of the precision of the sampling and analytical methods used on the Tank 48H samples.

  3. Statistically Qualified Neuro-Analytic system and Method for Process Monitoring

    SciTech Connect

    Vilim, Richard B.; Garcia, Humberto E.; Chen, Frederick W.

    1998-11-04

    An apparatus and method for monitoring a process involves development and application of a statistically qualified neuro-analytic (SQNA) model to accurately and reliably identify process change. The development of the SQNA model is accomplished in two steps: deterministic model adaption and stochastic model adaptation. Deterministic model adaption involves formulating an analytic model of the process representing known process characteristics,augmenting the analytic model with a neural network that captures unknown process characteristics, and training the resulting neuro-analytic model by adjusting the neural network weights according to a unique scaled equation emor minimization technique. Stochastic model adaptation involves qualifying any remaining uncertainty in the trained neuro-analytic model by formulating a likelihood function, given an error propagation equation, for computing the probability that the neuro-analytic model generates measured process output. Preferably, the developed SQNA model is validated using known sequential probability ratio tests and applied to the process as an on-line monitoring system.

  4. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Sun, Weimin; El-Sharawy, El-Budawy; Aberle, James T.; Birtcher, Craig R.; Peng, Jian; Tirkas, Panayiotis A.

    1992-01-01

    The Advanced Helicopter Electromagnetics (AHE) Industrial Associates Program continues its research on variety of main topics identified and recommended by the Advisory Task Force of the program. The research activities center on issues that advance technology related to helicopter electromagnetics. While most of the topics are a continuation of previous works, special effort has been focused on some of the areas due to recommendations from the last annual conference. The main topics addressed in this report are: composite materials, and antenna technology. The area of composite materials continues getting special attention in this period. The research has focused on: (1) measurements of the electrical properties of low-conductivity materials; (2) modeling of material discontinuity and their effects on the scattering patterns; (3) preliminary analysis on interaction of electromagnetic fields with multi-layered graphite fiberglass plates; and (4) finite difference time domain (FDTD) modeling of fields penetration through composite panels of a helicopter.

  5. Method and apparatus for advancing tethers

    DOEpatents

    Zollinger, W.T.

    1998-06-02

    A tether puller for advancing a tether through a channel may include a bellows assembly having a leading end fixedly attached to the tether at a first position and a trailing end fixedly attached to the tether at a second position so that the leading and trailing ends of the bellows assembly are located a substantially fixed distance apart. The bellows assembly includes a plurality of independently inflatable elements each of which may be separately inflated to an extended position and deflated to a retracted position. Each of the independently inflatable elements expands radially and axially upon inflation. An inflation system connected to the independently inflatable elements inflates and deflates selected ones of the independently inflatable elements to cause the bellows assembly to apply a tractive force to the tether and advance it in the channel. 9 figs.

  6. Method and apparatus for advancing tethers

    DOEpatents

    Zollinger, W. Thor

    1998-01-01

    A tether puller for advancing a tether through a channel may include a bellows assembly having a leading end fixedly attached to the tether at a first position and a trailing end fixedly attached to the tether at a second position so that the leading and trailing ends of the bellows assembly are located a substantially fixed distance apart. The bellows assembly includes a plurality of independently inflatable elements each of which may be separately inflated to an extended position and deflated to a retracted position. Each of the independently inflatable elements expands radially and axially upon inflation. An inflation system connected to the independently inflatable elements inflates and deflates selected ones of the independently inflatable elements to cause the bellows assembly to apply a tractive force to the tether and advance it in the channel.

  7. Manual of analytical methods for the Industrial Hygiene Chemistry Laboratory

    SciTech Connect

    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.

  8. Analytic method for calculating properties of random walks on networks

    NASA Technical Reports Server (NTRS)

    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.

  9. Downstream processing and chromatography based analytical methods for production of vaccines, gene therapy vectors, and bacteriophages

    PubMed Central

    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

  10. Base flow separation: A comparison of analytical and mass balance methods

    NASA Astrophysics Data System (ADS)

    Lott, Darline A.; Stewart, Mark T.

    2016-04-01

    Base flow is the ground water contribution to stream flow. Many activities, such as water resource management, calibrating hydrological and climate models, and studies of basin hydrology, require good estimates of base flow. The base flow component of stream flow is usually determined by separating a stream hydrograph into two components, base flow and runoff. Analytical methods, mathematical functions or algorithms used to calculate base flow directly from discharge, are the most widely used base flow separation methods and are often used without calibration to basin or gage-specific parameters other than basin area. In this study, six analytical methods are compared to a mass balance method, the conductivity mass-balance (CMB) method. The base flow index (BFI) values for 35 stream gages are obtained from each of the seven methods with each gage having at least two consecutive years of specific conductance data and 30 years of continuous discharge data. BFI is cumulative base flow divided by cumulative total discharge over the period of record of analysis. The BFI value is dimensionless, and always varies from 0 to 1. Areas of basins used in this study range from 27 km2 to 68,117 km2. BFI was first determined for the uncalibrated analytical methods. The parameters of each analytical method were then calibrated to produce BFI values as close to the CMB derived BFI values as possible. One of the methods, the power function (aQb + cQ) method, is inherently calibrated and was not recalibrated. The uncalibrated analytical methods have an average correlation coefficient of 0.43 when compared to CMB-derived values, and an average correlation coefficient of 0.93 when calibrated with the CMB method. Once calibrated, the analytical methods can closely reproduce the base flow values of a mass balance method. Therefore, it is recommended that analytical methods be calibrated against tracer or mass balance methods.

  11. EVALUATION OF ANALYTICAL METHODS FOR DETERMINING PESTICIDES IN BABY FOOD

    EPA Science Inventory

    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...

  12. Analytical method for promoting process capability of shock absorption steel.

    PubMed

    Sung, Wen-Pei; Shih, Ming-Hsiang; Chen, Kuen-Suan

    2003-01-01

    Mechanical properties and low cycle fatigue are two factors that must be considered in developing new type steel for shock absorption. Process capability and process control are significant factors in achieving the purpose of research and development programs. Often-used evaluation methods failed to measure process yield and process centering; so this paper uses Taguchi loss function as basis to establish an evaluation method and the steps for assessing the quality of mechanical properties and process control of an iron and steel manufacturer. The establishment of this method can serve the research and development and manufacturing industry and lay a foundation in enhancing its process control ability to select better manufacturing processes that are more reliable than decision making by using the other commonly used methods.

  13. Leveraging Smart Meter Data through Advanced Analytics: Applications to Building Energy Efficiency

    NASA Astrophysics Data System (ADS)

    Jalori, Saurabh

    The poor energy efficiency of buildings is a major barrier to alleviating the energy dilemma. Historically, monthly utility billing data was widely available and analytical methods for identifying building energy efficiency improvements, performing building Monitoring and Verification (M&V) and continuous commissioning (CCx) were based on them. Although robust, these methods were not sensitive enough to detect a number of common causes for increased energy use. In recent years, prevalence of short-term building energy consumption data, also known as Energy Interval Data (EID), made available through the Smart Meters, along with data mining techniques presents the potential of knowledge discovery inherent in this data. This allows more sophisticated analytical tools to be developed resulting in greater sensitivities due to higher prediction accuracies; leading to deep energy savings and highly efficient building system operations. The research explores enhancements to Inverse Statistical Modeling techniques due to the availability of EID. Inverse statistical modeling is the process of identification of prediction model structure and estimates of model parameters. The methodology is based on several common statistical and data mining techniques: cluster analysis for day typing, outlier detection and removal, and generation of building scheduling. Inverse methods are simpler to develop and require fewer inputs for model identification. They can model changes in energy consumption based on changes in climatic variables and up to a certain extent, occupancy. This makes them easy-to-use and appealing to building managers for evaluating any general retrofits, building condition monitoring, continuous commissioning and short-term load forecasting (STLF). After evaluating several model structures, an elegant model form was derived which can be used to model daily energy consumption; which can be extended to model energy consumption for any specific hour by adding corrective

  14. Optimal analytic method for the nonlinear Hasegawa-Mima equation

    NASA Astrophysics Data System (ADS)

    Baxter, Mathew; Van Gorder, Robert A.; Vajravelu, Kuppalapalle

    2014-05-01

    The Hasegawa-Mima equation is a nonlinear partial differential equation that describes the electric potential due to a drift wave in a plasma. In the present paper, we apply the method of homotopy analysis to a slightly more general Hasegawa-Mima equation, which accounts for hyper-viscous damping or viscous dissipation. First, we outline the method for the general initial/boundary value problem over a compact rectangular spatial domain. We use a two-stage method, where both the convergence control parameter and the auxiliary linear operator are optimally selected to minimize the residual error due to the approximation. To do the latter, we consider a family of operators parameterized by a constant which gives the decay rate of the solutions. After outlining the general method, we consider a number of concrete examples in order to demonstrate the utility of this approach. The results enable us to study properties of the initial/boundary value problem for the generalized Hasegawa-Mima equation. In several cases considered, we are able to obtain solutions with extremely small residual errors after relatively few iterations are computed (residual errors on the order of 10-15 are found in multiple cases after only three iterations). The results demonstrate that selecting a parameterized auxiliary linear operator can be extremely useful for minimizing residual errors when used concurrently with the optimal homotopy analysis method, suggesting that this approach can prove useful for a number of nonlinear partial differential equations arising in physics and nonlinear mechanics.

  15. An analytical method to predict efficiency of aircraft gearboxes

    NASA Technical Reports Server (NTRS)

    Anderson, N. E.; Loewenthal, S. H.; Black, J. D.

    1984-01-01

    A spur gear efficiency prediction method previously developed by the authors was extended to include power loss of planetary gearsets. A friction coefficient model was developed for MIL-L-7808 oil based on disc machine data. This combined with the recent capability of predicting losses in spur gears of nonstandard proportions allows the calculation of power loss for complete aircraft gearboxes that utilize spur gears. The method was applied to the T56/501 turboprop gearbox and compared with measured test data. Bearing losses were calculated with large scale computer programs. Breakdowns of the gearbox losses point out areas for possible improvement.

  16. Teaching Analytical Method Development in an Undergraduate Instrumental Analysis Course

    ERIC Educational Resources Information Center

    Lanigan, Katherine C.

    2008-01-01

    Method development and assessment, central components of carrying out chemical research, require problem-solving skills. This article describes a pedagogical approach for teaching these skills through the adaptation of published experiments and application of group-meeting style discussions to the curriculum of an undergraduate instrumental…

  17. MSFC Advanced Concepts Office and the Iterative Launch Vehicle Concept Method

    NASA Technical Reports Server (NTRS)

    Creech, Dennis

    2011-01-01

    This slide presentation reviews the work of the Advanced Concepts Office (ACO) at Marshall Space Flight Center (MSFC) with particular emphasis on the method used to model launch vehicles using INTegrated ROcket Sizing (INTROS), a modeling system that assists in establishing the launch concept design, and stage sizing, and facilitates the integration of exterior analytic efforts, vehicle architecture studies, and technology and system trades and parameter sensitivities.

  18. Advanced electromagnetic methods for aerospace vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; El-Sharawy, El-Budawy; Hashemi-Yeganeh, Shahrokh; Aberle, James T.; Birtcher, Craig R.

    1991-01-01

    The Advanced Helicopter Electromagnetics is centered on issues that advance technology related to helicopter electromagnetics. Progress was made on three major topics: composite materials; precipitation static corona discharge; and antenna technology. In composite materials, the research has focused on the measurements of their electrical properties, and the modeling of material discontinuities and their effect on the radiation pattern of antennas mounted on or near material surfaces. The electrical properties were used to model antenna performance when mounted on composite materials. Since helicopter platforms include several antenna systems at VHF and UHF bands, measuring techniques are being explored that can be used to measure the properties at these bands. The effort on corona discharge and precipitation static was directed toward the development of a new two dimensional Voltage Finite Difference Time Domain computer program. Results indicate the feasibility of using potentials for simulating electromagnetic problems in the cases where potentials become primary sources. In antenna technology the focus was on Polarization Diverse Conformal Microstrip Antennas, Cavity Backed Slot Antennas, and Varactor Tuned Circular Patch Antennas. Numerical codes were developed for the analysis of two probe fed rectangular and circular microstrip patch antennas fed by resistive and reactive power divider networks.

  19. EVALUATION OF ANALYTICAL REPORTING ERRORS GENERATED AS DESCRIBED IN SW-846 METHOD 8261A

    EPA Science Inventory

    SW-846 Method 8261A incorporates the vacuum distillation of analytes from samples, and their recoveries are characterized by internal standards. The internal standards measure recoveries with confidence intervals as functions of physical properties. The frequency the calculate...

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

    EPA Science Inventory

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

  1. Integrated homeland security system with passive thermal imaging and advanced video analytics

    NASA Astrophysics Data System (ADS)

    Francisco, Glen; Tillman, Jennifer; Hanna, Keith; Heubusch, Jeff; Ayers, Robert

    2007-04-01

    for creating initial alerts - we refer to this as software level detection, the next level building block Immersive 3D visual assessment for situational awareness and to manage the reaction process - we refer to this as automated intelligent situational awareness, a third building block Wide area command and control capabilities to allow control from a remote location - we refer to this as the management and process control building block integrating together the lower level building elements. In addition, this paper describes three live installations of complete, total systems that incorporate visible and thermal cameras as well as advanced video analytics. Discussion of both system elements and design is extensive.

  2. [Progress in sample preparation and analytical methods for trace polar small molecules in complex samples].

    PubMed

    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. PMID:26753274

  3. A Vocal-Based Analytical Method for Goose Behaviour Recognition

    PubMed Central

    Steen, Kim Arild; Therkildsen, Ole Roland; Karstoft, Henrik; Green, Ole

    2012-01-01

    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-linear capabilities 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 a wildlife management system. PMID:22737037

  4. A vocal-based analytical method for goose behaviour recognition.

    PubMed

    Steen, Kim Arild; Therkildsen, Ole Roland; Karstoft, Henrik; Green, Ole

    2012-01-01

    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-linear capabilities 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 a wildlife management system.

  5. Using an analytical geometry method to improve tiltmeter data presentation

    USGS Publications Warehouse

    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.

  6. Analytical methods of laser spectroscopy for biomedical applications

    NASA Astrophysics Data System (ADS)

    Martyshkin, Dmitri V.

    Different aspects of the application of laser spectroscopy in biomedical research have been considered. A growing demand for molecular sensing techniques in biomedical and environmental research has led the introduction of existing spectroscopic techniques, as well as development of new methods. The applications of laser-induced fluorescence, Raman scattering, cavity ring-down spectroscopy, and laser-induced breakdown spectroscopy for the monitoring of superoxide dismutase (SOD) and hemoglobin levels, the study of the characteristics of light-curing dental restorative materials, and the environmental monitoring of levels of toxic metal ion is presented. The development of new solid-state tunable laser sources based on color center crystals for these applications is presented as well.

  7. A simple parallel analytical method of prenatal screening.

    PubMed

    Li, Ding; Yang, Hao; Zhang, Wen-Hong; Pan, Hao; Wen, Dong-Qing; Han, Feng-Chan; Guo, Hui-Fang; Wang, Xiao-Ming; Yan, Xiao-Jun

    2006-01-01

    Protein microarray has progressed rapidly in the past few years, but it is still hard to popularize it in many developing countries or small hospitals owing to the technical expertise required in practice. We developed a cheap and easy-to-use protein microarray based on dot immunogold filtration assay for parallel analysis of ToRCH-related antibodies including Toxoplasma gondii, rubella virus, cytomegalovirus and herpes simplex virus type 1 and 2 in sera of pregnant women. It does not require any expensive instruments and the assay results can be clearly recognized by the naked eye. We analyzed 186 random sera of outpatients at the gynecological department with our microarray and commercial ELISA kit, and the results showed there was no significant difference between the two detection methods. Validated by clinical application, the microarray is easy to use and has a unique advantage in cost and time. It is more suitable for mass prenatal screening or epidemiological screening than the ELISA format.

  8. Analytical Chemistry Laboratory (ACL) procedure compendium. Volume 4, Organic methods

    SciTech Connect

    Not Available

    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.

  9. Advanced particulate matter control apparatus and methods

    DOEpatents

    Miller, Stanley J.; Zhuang, Ye; Almlie, Jay C.

    2012-01-10

    Apparatus and methods for collection and removal of particulate matter, including fine particulate matter, from a gas stream, comprising a unique combination of high collection efficiency and ultralow pressure drop across the filter. The apparatus and method utilize simultaneous electrostatic precipitation and membrane filtration of a particular pore size, wherein electrostatic collection and filtration occur on the same surface.

  10. An introduction to clinical microeconomic analysis: purposes and analytic methods.

    PubMed

    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) PMID:10151059

  11. Overview of current methods in sedimentation velocity and sedimentation equilibrium analytical ultracentrifugation.

    PubMed

    Zhao, Huaying; Brautigam, Chad A; Ghirlando, Rodolfo; Schuck, Peter

    2013-02-01

    Modern computational strategies have allowed for the direct modeling of the sedimentation process of heterogeneous mixtures, resulting in sedimentation velocity (SV) size-distribution analyses with significantly improved detection limits and strongly enhanced resolution. These advances have transformed the practice of SV, rendering it the primary method of choice for most existing applications of analytical ultracentrifugation (AUC), such as the study of protein self- and hetero-association, the study of membrane proteins, and applications in biotechnology. New global multisignal modeling and mass conservation approaches in SV and sedimentation equilibrium (SE), in conjunction with the effective-particle framework for interpreting the sedimentation boundary structure of interacting systems, as well as tools for explicit modeling of the reaction/diffusion/sedimentation equations to experimental data, have led to more robust and more powerful strategies for the study of reversible protein interactions and multiprotein complexes. Furthermore, modern mathematical modeling capabilities have allowed for a detailed description of many experimental aspects of the acquired data, thus enabling novel experimental opportunities, with important implications for both sample preparation and data acquisition. The goal of the current unit is to describe the current tools for the study of soluble proteins, detergent-solubilized membrane proteins and their interactions by SV and SE.

  12. [Final goal and problems in clinical chemistry examination measured by advanced analytical instruments].

    PubMed

    Sasaki, M; Hashimoto, E

    1993-07-01

    In the field of clinical chemistry of Japan, the automation of analytical instruments first appeared in the 1960's with the rapid developments in electronics industry. After a series of improvements and modifications in the past thirty years, these analytical instruments became excellent with multifunctions. From the results of these developments, it is now well recognized that automated analytical instruments are indispensable to manage the modern clinical Laboratory. On the other hand, these automated analytical instruments uncovered the various problems which had been hitherto undetected when the manually-operated instruments were used. For instances, the variation of commercially available standard solutions due to the lack of government control causes the different values obtained in institutions. In addition, there are many problems such as a shortage of medical technologists, a complication to handle the sampling and an increased labor costs. Furthermore, the inadequacies in maintenance activities cause the frequent erroneous reports of laboratory findings in spite of the latest and efficient analytical instruments equipped. Thus, the working process in clinical laboratory must be systematized to create the rapidity and the effectiveness. In the present report, we review the developmental history of automation system for analytical instruments, discuss the problems to create the effective clinical laboratory and explore the ways to deal with these emerging issues for the automation technology in clinical laboratory.

  13. Analytical recovery of protozoan enumeration methods: have drinking water QMRA models corrected or created bias?

    PubMed

    Schmidt, P J; Emelko, M B; Thompson, M E

    2013-05-01

    Quantitative microbial risk assessment (QMRA) is a tool to evaluate the potential implications of pathogens in a water supply or other media and is of increasing interest to regulators. In the case of potentially pathogenic protozoa (e.g. Cryptosporidium oocysts and Giardia cysts), it is well known that the methods used to enumerate (oo)cysts in samples of water and other media can have low and highly variable analytical recovery. In these applications, QMRA has evolved from ignoring analytical recovery to addressing it in point-estimates of risk, and then to addressing variation of analytical recovery in Monte Carlo risk assessments. Often, variation of analytical recovery is addressed in exposure assessment by dividing concentration values that were obtained without consideration of analytical recovery by random beta-distributed recovery values. A simple mathematical proof is provided to demonstrate that this conventional approach to address non-constant analytical recovery in drinking water QMRA will lead to overestimation of mean pathogen concentrations. The bias, which can exceed an order of magnitude, is greatest when low analytical recovery values are common. A simulated dataset is analyzed using a diverse set of approaches to obtain distributions representing temporal variation in the oocyst concentration, and mean annual risk is then computed from each concentration distribution using a simple risk model. This illustrative example demonstrates that the bias associated with mishandling non-constant analytical recovery and non-detect samples can cause drinking water systems to be erroneously classified as surpassing risk thresholds.

  14. Indentation Methods in Advanced Materials Research Introduction

    SciTech Connect

    Pharr, George Mathews; Cheng, Yang-Tse; Hutchings, Ian; Sakai, Mototsugu; Moody, Neville; Sundararajan, G.; Swain, Michael V.

    2009-01-01

    Since its commercialization early in the 20th century, indentation testing has played a key role in the development of new materials and understanding their mechanical behavior. Progr3ess in the field has relied on a close marriage between research in the mechanical behavior of materials and contact mechanics. The seminal work of Hertz laid the foundations for bringing these two together, with his contributions still widely utilized today in examining elastic behavior and the physics of fracture. Later, the pioneering work of Tabor, as published in his classic text 'The Hardness of Metals', exapdned this understanding to address the complexities of plasticity. Enormous progress in the field has been achieved in the last decade, made possible both by advances in instrumentation, for example, load and depth-sensing indentation and scanning electron microscopy (SEM) and transmission electron microscopy (TEM) based in situ testing, as well as improved modeling capabilities that use computationally intensive techniques such as finite element analysis and molecular dynamics simulation. The purpose of this special focus issue is to present recent state of the art developments in the field.

  15. Advanced spectral methods for climatic time series

    USGS Publications Warehouse

    Ghil, M.; Allen, M.R.; Dettinger, M.D.; Ide, K.; Kondrashov, D.; Mann, M.E.; Robertson, A.W.; Saunders, A.; Tian, Y.; Varadi, F.; Yiou, P.

    2002-01-01

    The analysis of univariate or multivariate time series provides crucial information to describe, understand, and predict climatic variability. The discovery and implementation of a number of novel methods for extracting useful information from time series has recently revitalized this classical field of study. Considerable progress has also been made in interpreting the information so obtained in terms of dynamical systems theory. In this review we describe the connections between time series analysis and nonlinear dynamics, discuss signal- to-noise enhancement, and present some of the novel methods for spectral analysis. The various steps, as well as the advantages and disadvantages of these methods, are illustrated by their application to an important climatic time series, the Southern Oscillation Index. This index captures major features of interannual climate variability and is used extensively in its prediction. Regional and global sea surface temperature data sets are used to illustrate multivariate spectral methods. Open questions and further prospects conclude the review.

  16. Approximate Analytical Solutions of the Regularized Long Wave Equation Using the Optimal Homotopy Perturbation Method

    PubMed Central

    Căruntu, Bogdan

    2014-01-01

    The paper presents the optimal homotopy perturbation method, which is a new method to find approximate analytical solutions for nonlinear partial differential equations. Based on the well-known homotopy perturbation method, the optimal homotopy perturbation method presents an accelerated convergence compared to the regular homotopy perturbation method. The applications presented emphasize the high accuracy of the method by means of a comparison with previous results. PMID:25003150

  17. Analytical methods for quantifying environmental connectivity for the control and surveillance of infectious disease spread

    PubMed Central

    Remais, Justin; Akullian, Adam; Ding, Lu; Seto, Edmund

    2010-01-01

    The sustained transmission and spread of environmentally mediated infectious diseases is governed in part by the dispersal of parasites, disease vectors and intermediate hosts between sites of transmission. Functional geospatial models can be used to quantify and predict the degree to which environmental features facilitate or limit connectivity between target populations, yet typical models are limited in their geographical and analytical approach, providing simplistic, global measures of connectivity and lacking methods to assess the epidemiological implications of fine-scale heterogeneous landscapes. Here, functional spatial models are applied to problems of surveillance and control of the parasitic blood fluke Schistosoma japonicum and its intermediate snail host Oncomelania haupensis in western China. We advance functional connectivity methods by providing an analytical framework to (i) identify nodes of transmission where the degree of connectedness to other villages, and thus the potential for disease spread, is higher than is estimated using Euclidean distance alone and (ii) (re)organize transmission sites into disease surveillance units based on second-order relationships among nodes using non-Euclidean distance measures, termed effective geographical distance (EGD). Functional environmental models are parametrized using ecological information on the target organisms, and pair-wise distributions of inter-node EGD are estimated. A Monte Carlo rank product analysis is presented to identify nearby nodes under alternative distance models. Nodes are then iteratively embedded into EGD space and clustered using a k-means algorithm to group villages into ecologically meaningful surveillance groups. A consensus clustering approach is taken to derive the most stable cluster structure. The results indicate that novel relationships between nodes are revealed when non-Euclidean, ecologically determined distance measures are used to quantify connectivity in

  18. A Comparative Evaluation of Analytical Methods to Allocate Individual Marks from a Team Mark

    ERIC Educational Resources Information Center

    Nepal, Kali

    2012-01-01

    This study presents a comparative evaluation of analytical methods to allocate individual marks from a team mark. Only the methods that use or can be converted into some form of mathematical equations are analysed. Some of these methods focus primarily on the assessment of the quality of teamwork product (product assessment) while the others put…

  19. Integrative Mixed Methods Data Analytic Strategies in Research on School Success in Challenging Circumstances

    ERIC Educational Resources Information Center

    Jang, Eunice E.; McDougall, Douglas E.; Pollon, Dawn; Herbert, Monique; Russell, Pia

    2008-01-01

    There are both conceptual and practical challenges in dealing with data from mixed methods research studies. There is a need for discussion about various integrative strategies for mixed methods data analyses. This article illustrates integrative analytic strategies for a mixed methods study focusing on improving urban schools facing challenging…

  20. 75 FR 49930 - Stakeholder Meeting Regarding Re-Evaluation of Currently Approved Total Coliform Analytical Methods

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-16

    ... Methods AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: The Environmental...) analytical methods. At these meetings, stakeholders will be given an opportunity to discuss potential elements of a method re-evaluation study, such as developing a reference coliform/non-coliform library...

  1. Advances in methods for deepwater TLP installations

    SciTech Connect

    Wybro, P.G.

    1995-10-01

    This paper describes a method suitable for installing deepwater TLP structures in water depths beyond 3,000 ft. An overview is presented of previous TLP installation, wherein an evaluation is made of the various methods and their suitability to deepwater applications. A novel method for installation of deepwater TLP`s is described. This method of installation is most suitable for deepwater and/or large TLP structures, but can also be used in moderate water depth as well. The tendon installation method utilizes the so-called Platform Arrestor Concept (PAC), wherein tendon sections are transported by barges to site, and assembled vertically using a dynamically position crane vessel. The tendons are transferred to the platform where they are hung off until there are a full complement of tendons. The hull lock off operation is performed on all tendons simultaneously, avoiding dangerous platform resonant behavior. The installation calls for relatively simple installation equipment, and also enables the use of simple tendon tie-off equipment, such as a single piece nut.

  2. Waste Tank Organic Safety Program: Analytical methods development. Progress report, FY 1994

    SciTech Connect

    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.

  3. Protein Microarrays with Novel Microfluidic Methods: Current Advances

    PubMed Central

    Dixit, Chandra K.; Aguirre, Gerson R.

    2014-01-01

    Microfluidic-based micromosaic technology has allowed the pattering of recognition elements in restricted micrometer scale areas with high precision. This controlled patterning enabled the development of highly multiplexed arrays multiple analyte detection. This arraying technology was first introduced in the beginning of 2001 and holds tremendous potential to revolutionize microarray development and analyte detection. Later, several microfluidic methods were developed for microarray application. In this review we discuss these novel methods and approaches which leverage the property of microfluidic technologies to significantly improve various physical aspects of microarray technology, such as enhanced imprinting homogeneity, stability of the immobilized biomolecules, decreasing assay times, and reduction of the costs and of the bulky instrumentation.

  4. Advanced method for making vitreous waste forms

    SciTech Connect

    Pope, J.M.; Harrison, D.E.

    1980-01-01

    A process is described for making waste glass that circumvents the problems of dissolving nuclear waste in molten glass at high temperatures. Because the reactive mixing process is independent of the inherent viscosity of the melt, any glass composition can be prepared with equal facility. Separation of the mixing and melting operations permits novel glass fabrication methods to be employed.

  5. Advanced Electromagnetic Methods for Aerospace Vehicles

    NASA Technical Reports Server (NTRS)

    Balanis, Constantine A.; Polycarpou, Anastasis; Birtcher, Craig R.; Georgakopoulos, Stavros; Han, Dong-Ho; Ballas, Gerasimos

    1999-01-01

    The imminent destructive threats of Lightning on helicopters and other airborne systems has always been a topic of great interest to this research grant. Previously, the lightning induced currents on the surface of the fuselage and its interior were predicted using the finite-difference time-domain (FDTD) method as well as the NEC code. The limitations of both methods, as applied to lightning, were identified and extensively discussed in the last meeting. After a thorough investigation of the capabilities of the FDTD, it was decided to incorporate into the numerical method a subcell model to accurately represent current diffusion through conducting materials of high conductivity and finite thickness. Because of the complexity of the model, its validity will be first tested for a one-dimensional FDTD problem. Although results are not available yet, the theory and formulation of the subcell model are presented and discussed here to a certain degree. Besides lightning induced currents in the interior of an aircraft, penetration of electromagnetic fields through apertures (e.g., windows and cracks) could also be devastating for the navigation equipment, electronics, and communications systems in general. The main focus of this study is understanding and quantifying field penetration through apertures. The simulation is done using the FDTD method and the predictions are compared with measurements and moment method solutions obtained from the NASA Langley Research Center. Cavity-backed slot (CBS) antennas or slot antennas in general have many applications in aircraft-satellite type of communications. These can be flushmounted on the surface of the fuselage and, therefore, they retain the aerodynamic shape of the aircraft. In the past, input impedance and radiation patterns of CBS antennas were computed using a hybrid FEM/MoM code. The analysis is now extended to coupling between two identical slot antennas mounted on the same structure. The predictions are performed

  6. Comparison of Analytical Methods: Direct Emission versus First-Derivative Fluorometric Methods for Quinine Determination in Tonic Waters

    NASA Astrophysics Data System (ADS)

    Pandey, Siddharth; Borders, Tammie L.; Hernández, Carmen E.; Roy, Lindsay E.; Reddy, Gaddum D.; Martinez, Geo L.; Jackson, Autumn; Brown, Guenevere; Acree, William E., Jr.

    1999-01-01

    An undergraduate laboratory experiment is designed for the quantitative determination of quinine in tonic water samples. It is based upon direct fluorescence emission and first-derivative spectroscopic methods. Unlike other published laboratory experiments, our method exposes students to the general method of derivative spectroscopy, an important, often-used analytical technique for eliminating sample matrix and background absorbance effects and for treating overlapped spectral bands. The statistical treatment allows students to compare concentrations directly calculated from the measured fluorescence emission intensity with values obtained from the first-derivative emission spectra, to ascertain whether there is a difference between the two analytical methods. Method selection and validation are important items routinely encountered by practicing analytical chemists.

  7. Cost estimating methods for advanced space systems

    NASA Technical Reports Server (NTRS)

    Cyr, Kelley

    1988-01-01

    Parametric cost estimating methods for space systems in the conceptual design phase are developed. The approach is to identify variables that drive cost such as weight, quantity, development culture, design inheritance, and time. The relationship between weight and cost is examined in detail. A theoretical model of cost is developed and tested statistically against a historical data base of major research and development programs. It is concluded that the technique presented is sound, but that it must be refined in order to produce acceptable cost estimates.

  8. Advances in organometallic synthesis with mechanochemical methods.

    PubMed

    Rightmire, Nicholas R; Hanusa, Timothy P

    2016-02-14

    Solvent-based syntheses have long been normative in all areas of chemistry, although mechanochemical methods (specifically grinding and milling) have been used to good effect for decades in organic, and to a lesser but growing extent, inorganic coordination chemistry. Organometallic synthesis, in contrast, represents a relatively underdeveloped area for mechanochemical research, and the potential benefits are considerable. From access to new classes of unsolvated complexes, to control over stoichiometries that have not been observed in solution routes, mechanochemical (or 'M-chem') approaches have much to offer the synthetic chemist. It has already become clear that removing the solvent from an organometallic reaction can change reaction pathways considerably, so that prediction of the outcome is not always straightforward. This Perspective reviews recent developments in the field, and describes equipment that can be used in organometallic synthesis. Synthetic chemists are encouraged to add mechanochemical methods to their repertoire in the search for new and highly reactive metal complexes and novel types of organometallic transformations.

  9. Advances in explosives analysis—part I. animal, chemical, ion, and mechanical methods

    SciTech Connect

    Brown, Kathryn E.; Greenfield, Margo T.; McGrane, Shawn D.; Moore, David S.

    2015-10-13

    The number and capability of explosives detection and analysis methods have increased substantially since the publication of the Analytical and Bioanalytical Chemistry special issue devoted to Explosives Analysis (Moore and Goodpaster, Anal Bioanal Chem 395(2):245–246, 2009). We review and critically evaluate the latest (the past five years) important advances in explosives detection, with details of the improvements over previous methods, and suggest possible avenues towards further advances in, e.g., stand-off distance, detection limit, selectivity, and penetration through camouflage or packaging. The review consists of two parts. Moreover, Part I, reviews methods based on animals, chemicals (including colorimetry, molecularly imprinted polymers, electrochemistry, and immunochemistry), ions (both ion-mobility spectrometry and mass spectrometry), and mechanical devices. Part II will review methods based on photons, from very energetic photons including X-rays and gamma rays down to the terahertz range, and neutrons.

  10. Advances in explosives analysis—part I. animal, chemical, ion, and mechanical methods

    DOE PAGES

    Brown, Kathryn E.; Greenfield, Margo T.; McGrane, Shawn D.; Moore, David S.

    2015-10-13

    The number and capability of explosives detection and analysis methods have increased substantially since the publication of the Analytical and Bioanalytical Chemistry special issue devoted to Explosives Analysis (Moore and Goodpaster, Anal Bioanal Chem 395(2):245–246, 2009). We review and critically evaluate the latest (the past five years) important advances in explosives detection, with details of the improvements over previous methods, and suggest possible avenues towards further advances in, e.g., stand-off distance, detection limit, selectivity, and penetration through camouflage or packaging. The review consists of two parts. Moreover, Part I, reviews methods based on animals, chemicals (including colorimetry, molecularly imprinted polymers,more » electrochemistry, and immunochemistry), ions (both ion-mobility spectrometry and mass spectrometry), and mechanical devices. Part II will review methods based on photons, from very energetic photons including X-rays and gamma rays down to the terahertz range, and neutrons.« less

  11. Advances in explosives analysis—part II: photon and neutron methods

    DOE PAGES

    Brown, Kathryn E.; Greenfield, Margo T.; McGrane, Shawn D.; Moore, David S.

    2015-10-07

    The number and capability of explosives detection and analysis methods have increased dramatically since publication of the Analytical and Bioanalytical Chemistry special issue devoted to Explosives Analysis [Moore DS, Goodpaster JV, Anal Bioanal Chem 395:245–246, 2009]. Here we review and critically evaluate the latest (the past five years) important advances in explosives detection, with details of the improvements over previous methods, and suggest possible avenues towards further advances in, e.g., stand-off distance, detection limit, selectivity, and penetration through camouflage or packaging. Our review consists of two parts. Part I discussed methods based on animals, chemicals (including colorimetry, molecularly imprinted polymers,more » electrochemistry, and immunochemistry), ions (both ion-mobility spectrometry and mass spectrometry), and mechanical devices. In Part II, we review methods based on photons, from very energetic photons including X-rays and gamma rays down to the terahertz range, and neutrons.« less

  12. Advances in explosives analysis—part II: photon and neutron methods

    SciTech Connect

    Brown, Kathryn E.; Greenfield, Margo T.; McGrane, Shawn D.; Moore, David S.

    2015-10-07

    The number and capability of explosives detection and analysis methods have increased dramatically since publication of the Analytical and Bioanalytical Chemistry special issue devoted to Explosives Analysis [Moore DS, Goodpaster JV, Anal Bioanal Chem 395:245–246, 2009]. Here we review and critically evaluate the latest (the past five years) important advances in explosives detection, with details of the improvements over previous methods, and suggest possible avenues towards further advances in, e.g., stand-off distance, detection limit, selectivity, and penetration through camouflage or packaging. Our review consists of two parts. Part I discussed methods based on animals, chemicals (including colorimetry, molecularly imprinted polymers, electrochemistry, and immunochemistry), ions (both ion-mobility spectrometry and mass spectrometry), and mechanical devices. In Part II, we review methods based on photons, from very energetic photons including X-rays and gamma rays down to the terahertz range, and neutrons.

  13. Advances in explosives analysis--part I: animal, chemical, ion, and mechanical methods.

    PubMed

    Brown, Kathryn E; Greenfield, Margo T; McGrane, Shawn D; Moore, David S

    2016-01-01

    The number and capability of explosives detection and analysis methods have increased substantially since the publication of the Analytical and Bioanalytical Chemistry special issue devoted to Explosives Analysis (Moore and Goodpaster, Anal Bioanal Chem 395(2):245-246, 2009). Here we review and critically evaluate the latest (the past five years) important advances in explosives detection, with details of the improvements over previous methods, and suggest possible avenues towards further advances in, e.g., stand-off distance, detection limit, selectivity, and penetration through camouflage or packaging. The review consists of two parts. This part, Part I, reviews methods based on animals, chemicals (including colorimetry, molecularly imprinted polymers, electrochemistry, and immunochemistry), ions (both ion-mobility spectrometry and mass spectrometry), and mechanical devices. Part II will review methods based on photons, from very energetic photons including X-rays and gamma rays down to the terahertz range, and neutrons.

  14. Synergistic effect of combining two nondestructive analytical methods for multielemental analysis.

    PubMed

    Toh, Yosuke; Ebihara, Mitsuru; Kimura, Atsushi; Nakamura, Shoji; Harada, Hideo; Hara, Kaoru Y; Koizumi, Mitsuo; Kitatani, Fumito; Furutaka, Kazuyoshi

    2014-12-16

    We developed a new analytical technique that combines prompt gamma-ray analysis (PGA) and time-of-flight elemental analysis (TOF) by using an intense pulsed neutron beam at the Japan Proton Accelerator Research Complex. It allows us to obtain the results from both methods at the same time. Moreover, it can be used to quantify elemental concentrations in the sample, to which neither of these methods can be applied independently, if a new analytical spectrum (TOF-PGA) is used. To assess the effectiveness of the developed method, a mixed sample of Ag, Au, Cd, Co, and Ta, and the Gibeon meteorite were analyzed. The analytical capabilities were compared based on the gamma-ray peak selectivity and signal-to-noise ratios. TOF-PGA method showed high merits, although the capability may differ based on the target and coexisting elements. PMID:25371049

  15. Advancements in Research Synthesis Methods: From a Methodologically Inclusive Perspective

    ERIC Educational Resources Information Center

    Suri, Harsh; Clarke, David

    2009-01-01

    The dominant literature on research synthesis methods has positivist and neo-positivist origins. In recent years, the landscape of research synthesis methods has changed rapidly to become inclusive. This article highlights methodologically inclusive advancements in research synthesis methods. Attention is drawn to insights from interpretive,…

  16. A method based on stochastic resonance for the detection of weak analytical signal.

    PubMed

    Wu, Xiaojing; Guo, Weiming; Cai, Wensheng; Shao, Xueguang; Pan, Zhongxiao

    2003-12-23

    An effective method for detection of weak analytical signals with strong noise background is proposed based on the theory of stochastic resonance (SR). Compared with the conventional SR-based algorithms, the proposed algorithm is simplified by changing only one parameter to realize the weak signal detection. Simulation studies revealed that the method performs well in detection of analytical signals in very high level of noise background and is suitable for detecting signals with the different noise level by changing the parameter. Applications of the method to experimental weak signals of X-ray diffraction and Raman spectrum are also investigated. It is found that reliable results can be obtained.

  17. Current methods and advances in bone densitometry

    NASA Technical Reports Server (NTRS)

    Guglielmi, G.; Gluer, C. C.; Majumdar, S.; Blunt, B. A.; Genant, H. K.

    1995-01-01

    Bone mass is the primary, although not the only, determinant of fracture. Over the past few years a number of noninvasive techniques have been developed to more sensitively quantitate bone mass. These include single and dual photon absorptiometry (SPA and DPA), single and dual X-ray absorptiometry (SXA and DXA) and quantitative computed tomography (QCT). While differing in anatomic sites measured and in their estimates of precision, accuracy, and fracture discrimination, all of these methods provide clinically useful measurements of skeletal status. It is the intent of this review to discuss the pros and cons of these techniques and to present the new applications of ultrasound (US) and magnetic resonance (MRI) in the detection and management of osteoporosis.

  18. Method and ethics in advancing jury research.

    PubMed

    Robertshaw, P

    1998-10-01

    In this article the contemporary problems of the jury and jury research are considered. This is timely, in view of the current Home Office Consultation Paper on the future of, and alternatives to, the jury in serious fraud trials, to which the author has submitted representations on its jury aspects. The research position is dominated by the prohibitions in the Contempt of Court Act 1981. The types of indirect research on jury deliberation which have been achieved within this stricture are outlined. In the USA, direct research of the jury is possible but, for historical reasons, it has been in television documentaries that direct observation of the deliberation process has been achieved. The first issue is discussed and the problems of inauthenticity, 'the observer effect', and of existential invalidity in 'mock' or 'shadow' juries are noted. Finally, the kinds of issues that could be addressed if licensed jury deliberation research was legalized, are proposed. It is also suggested that there are methods available to transcend the problems associated with American direct research. PMID:9808945

  19. Cost estimating methods for advanced space systems

    NASA Technical Reports Server (NTRS)

    Cyr, Kelley

    1994-01-01

    NASA is responsible for developing much of the nation's future space technology. Cost estimates for new programs are required early in the planning process so that decisions can be made accurately. Because of the long lead times required to develop space hardware, the cost estimates are frequently required 10 to 15 years before the program delivers hardware. The system design in conceptual phases of a program is usually only vaguely defined and the technology used is so often state-of-the-art or beyond. These factors combine to make cost estimating for conceptual programs very challenging. This paper describes an effort to develop parametric cost estimating methods for space systems in the conceptual design phase. The approach is to identify variables that drive cost such as weight, quantity, development culture, design inheritance and time. The nature of the relationships between the driver variables and cost will be discussed. In particular, the relationship between weight and cost will be examined in detail. A theoretical model of cost will be developed and tested statistically against a historical database of major research and development projects.

  20. Advanced Fuzzy Potential Field Method for Mobile Robot Obstacle Avoidance

    PubMed Central

    Park, Jong-Wook; Kwak, Hwan-Joo; Kang, Young-Chang; Kim, Dong W.

    2016-01-01

    An advanced fuzzy potential field method for mobile robot obstacle avoidance is proposed. The potential field method primarily deals with the repulsive forces surrounding obstacles, while fuzzy control logic focuses on fuzzy rules that handle linguistic variables and describe the knowledge of experts. The design of a fuzzy controller—advanced fuzzy potential field method (AFPFM)—that models and enhances the conventional potential field method is proposed and discussed. This study also examines the rule-explosion problem of conventional fuzzy logic and assesses the performance of our proposed AFPFM through simulations carried out using a mobile robot. PMID:27123001

  1. Advanced Fuzzy Potential Field Method for Mobile Robot Obstacle Avoidance.

    PubMed

    Park, Jong-Wook; Kwak, Hwan-Joo; Kang, Young-Chang; Kim, Dong W

    2016-01-01

    An advanced fuzzy potential field method for mobile robot obstacle avoidance is proposed. The potential field method primarily deals with the repulsive forces surrounding obstacles, while fuzzy control logic focuses on fuzzy rules that handle linguistic variables and describe the knowledge of experts. The design of a fuzzy controller--advanced fuzzy potential field method (AFPFM)--that models and enhances the conventional potential field method is proposed and discussed. This study also examines the rule-explosion problem of conventional fuzzy logic and assesses the performance of our proposed AFPFM through simulations carried out using a mobile robot. PMID:27123001

  2. Contextual and Analytic Qualities of Research Methods Exemplified in Research on Teaching

    ERIC Educational Resources Information Center

    Svensson, Lennart; Doumas, Kyriaki

    2013-01-01

    The aim of the present article is to discuss contextual and analytic qualities of research methods. The arguments are specified in relation to research on teaching. A specific investigation is used as an example to illustrate the general methodological approach. It is argued that research methods should be carefully grounded in an understanding of…

  3. Flammable gas safety program. Analytical methods development: FY 1994 progress report

    SciTech Connect

    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).

  4. Study on Two Methods for Nonlinear Force-Free Extrapolation Based on Semi-Analytical Field

    NASA Astrophysics Data System (ADS)

    Liu, S.; Zhang, H. Q.; Su, J. T.; Song, M. T.

    2011-03-01

    In this paper, two semi-analytical solutions of force-free fields (Low and Lou, Astrophys. J. 352, 343, 1990) have been used to test two nonlinear force-free extrapolation methods. One is the boundary integral equation (BIE) method developed by Yan and Sakurai ( Solar Phys. 195, 89, 2000), and the other is the approximate vertical integration (AVI) method developed by Song et al. ( Astrophys. J. 649, 1084, 2006). Some improvements have been made to the AVI method to avoid the singular points in the process of calculation. It is found that the correlation coefficients between the first semi-analytical field and extrapolated field using the BIE method, and also that obtained by the improved AVI method, are greater than 90% below a height 10 of the 64×64 lower boundary. For the second semi-analytical field, these correlation coefficients are greater than 80% below the same relative height. Although differences between the semi-analytical solutions and the extrapolated fields exist for both the BIE and AVI methods, these two methods can give reliable results for heights of about 15% of the extent of the lower boundary.

  5. EVALUATION OF ANALYTICAL METHODS FOR DETERMINING PESTICIDES IN BABY FOOD AND ADULT DUPLICATE-DIET SAMPLES

    EPA Science Inventory

    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...

  6. System and Method for Providing a Climate Data Analytic Services Application Programming Interface Distribution Package

    NASA Technical Reports Server (NTRS)

    Schnase, John L. (Inventor); Duffy, Daniel Q. (Inventor); Tamkin, Glenn S. (Inventor)

    2016-01-01

    A system, method and computer-readable storage devices for providing a climate data analytic services application programming interface distribution package. The example system can provide various components. The system provides a climate data analytic services application programming interface library that enables software applications running on a client device to invoke the capabilities of a climate data analytic service. The system provides a command-line interface that provides a means of interacting with a climate data analytic service by issuing commands directly to the system's server interface. The system provides sample programs that call on the capabilities of the application programming interface library and can be used as templates for the construction of new client applications. The system can also provide test utilities, build utilities, service integration utilities, and documentation.

  7. An Analytical Investigation of Three General Methods of Calculating Chemical-Equilibrium Compositions

    NASA Technical Reports Server (NTRS)

    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.

  8. Review of Properties and Analytical Methods for the Determination of Norfloxacin.

    PubMed

    Chierentin, Lucas; Salgado, Hérida Regina Nunes

    2016-01-01

    The first-generation quinolones have their greatest potency against Gram-negative bacteria, but newly developed molecules have exhibited increased potency against Gram-positive bacteria, and existing agents are available with additional activity against anaerobic microorganisms. Norfloxacin is a broad-spectrum antimicrobial fluoroquinolone used against Gram-positive and Gram-negative organisms (aerobic organisms). There are different analytical methods available to determine norfloxacin applied in quality control of this medicine in order to ensure its effectiveness and safety. The authors present an overview of the fourth generation of quinolones, followed by the properties, applications, and analytical methods of norfloxacin. These results show several existing analytical techniques that are flexible and broad-based methods of analysis in different matrices. This article focuses on bionalytical and pharmaceutical quality-control applications, such as thin-layer chromatography, microbiological assay, spectrophotometry, capillary electrophoresis (CE), and high-performance liquid chromatography (HPLC).

  9. Advantages of Analytical Transformations in Monte Carlo Methods for Radiation Transport

    SciTech Connect

    McKinley, M S; Brooks III, E D; Daffin, F

    2004-12-13

    Monte Carlo methods for radiation transport typically attempt to solve an integral by directly sampling analog or weighted particles, which are treated as physical entities. Improvements to the methods involve better sampling, probability games or physical intuition about the problem. We show that significant improvements can be achieved by recasting the equations with an analytical transform to solve for new, non-physical entities or fields. This paper looks at one such transform, the difference formulation for thermal photon transport, showing a significant advantage for Monte Carlo solution of the equations for time dependent transport. Other related areas are discussed that may also realize significant benefits from similar analytical transformations.

  10. Possibilities of Utilizing the Method of Analytical Hierarchy Process Within the Strategy of Corporate Social Business

    NASA Astrophysics Data System (ADS)

    Drieniková, Katarína; Hrdinová, Gabriela; Naňo, Tomáš; Sakál, Peter

    2010-01-01

    The paper deals with the analysis of the theory of corporate social responsibility, risk management and the exact method of analytic hierarchic process that is used in the decision-making processes. The Chapters 2 and 3 focus on presentation of the experience with the application of the method in formulating the stakeholders' strategic goals within the Corporate Social Responsibility (CSR) and simultaneously its utilization in minimizing the environmental risks. The major benefit of this paper is the application of Analytical Hierarchy Process (AHP).

  11. Verification of an Analytical Method for Measuring Crystal Nucleation Rates in Glasses from DTA Data

    NASA Technical Reports Server (NTRS)

    Ranasinghe, K. S.; Wei, P. F.; Kelton, K. F.; Ray, C. S.; Day, D. E.

    2004-01-01

    A recently proposed analytical (DTA) method for estimating the nucleation rates in glasses has been evaluated by comparing experimental data with numerically computed nucleation rates for a model lithium disilicate glass. The time and temperature dependent nucleation rates were predicted using the model and compared with those values from an analysis of numerically calculated DTA curves. The validity of the numerical approach was demonstrated earlier by a comparison with experimental data. The excellent agreement between the nucleation rates from the model calculations and fiom the computer generated DTA data demonstrates the validity of the proposed analytical DTA method.

  12. Guidance for characterizing explosives contaminated soils: Sampling and selecting on-site analytical methods

    SciTech Connect

    Crockett, A.B.; Craig, H.D.; Jenkins, T.F.; Sisk, W.E.

    1996-09-01

    A large number of defense-related sites are contaminated with elevated levels of secondary explosives. Levels of contamination range from barely detectable to levels above 10% that need special handling due to the detonation potential. Characterization of explosives-contaminated sites is particularly difficult due to the very heterogeneous distribution of contamination in the environment and within samples. To improve site characterization, several options exist including collecting more samples, providing on-site analytical data to help direct the investigation, compositing samples, improving homogenization of samples, and extracting larger samples. On-site analytical methods are essential to more economical and improved characterization. On-site methods might suffer in terms of precision and accuracy, but this is more than offset by the increased number of samples that can be run. While verification using a standard analytical procedure should be part of any quality assurance program, reducing the number of samples analyzed by the more expensive methods can result in significantly reduced costs. Often 70 to 90% of the soil samples analyzed during an explosives site investigation do not contain detectable levels of contamination. Two basic types of on-site analytical methods are in wide use for explosives in soil, calorimetric and immunoassay. Calorimetric methods generally detect broad classes of compounds such as nitroaromatics or nitramines, while immunoassay methods are more compound specific. Since TNT or RDX is usually present in explosive-contaminated soils, the use of procedures designed to detect only these or similar compounds can be very effective.

  13. Advances in spectroscopic methods for quantifying soil carbon

    USGS Publications Warehouse

    Reeves, James B.; McCarty, Gregory W.; Calderon, Francisco; Hively, W. Dean

    2012-01-01

    The current gold standard for soil carbon (C) determination is elemental C analysis using dry combustion. However, this method requires expensive consumables, is limited by the number of samples that can be processed (~100/d), and is restricted to the determination of total carbon. With increased interest in soil C sequestration, faster methods of analysis are needed, and there is growing interest in methods based on diffuse reflectance spectroscopy in the visible, near-infrared or mid-infrared spectral ranges. These spectral methods can decrease analytical requirements and speed sample processing, be applied to large landscape areas using remote sensing imagery, and be used to predict multiple analytes simultaneously. However, the methods require localized calibrations to establish the relationship between spectral data and reference analytical data, and also have additional, specific problems. For example, remote sensing is capable of scanning entire watersheds for soil carbon content but is limited to the surface layer of tilled soils and may require difficult and extensive field sampling to obtain proper localized calibration reference values. The objective of this chapter is to discuss the present state of spectroscopic methods for determination of soil carbon.

  14. Advanced Ablative Insulators and Methods of Making Them

    NASA Technical Reports Server (NTRS)

    Congdon, William M.

    2005-01-01

    Advanced ablative (more specifically, charring) materials that provide temporary protection against high temperatures, and advanced methods of designing and manufacturing insulators based on these materials, are undergoing development. These materials and methods were conceived in an effort to replace the traditional thermal-protection systems (TPSs) of re-entry spacecraft with robust, lightweight, better-performing TPSs that can be designed and manufactured more rapidly and at lower cost. These materials and methods could also be used to make improved TPSs for general aerospace, military, and industrial applications.

  15. Evaluation of sampling and analytical methods for the determination of chlorodifluoromethane in air.

    PubMed

    Seymour, M J; Lucas, M F

    1993-05-01

    In January 1989, the Occupational Safety and Health Administration (OSHA) published revised permissible exposure limits (PELs) for 212 compounds and established PELs for 164 additional compounds. In cases where regulated compounds did not have specific sampling and analytical methods, methods were suggested by OSHA. The National Institute for Occupational Safety and Health (NIOSH) Manual of Analytical Methods (NMAM) Method 1020, which was developed for 1,1,2-trichloro-1,2,2-trifluoroethane, was suggested by OSHA for the determination of chlorodifluoromethane in workplace air. Because this method was developed for a liquid and chlorodifluoromethane is a gas, the ability of NMAM Method 1020 to adequately sample and quantitate chlorodifluoromethane was questioned and tested by researchers at NIOSH. The evaluation of NMAM Method 1020 for chlorodifluoromethane showed that the capacity of the 100/50-mg charcoal sorbent bed was limited, the standard preparation procedure was incorrect for a gas analyte, and the analyte had low solubility in carbon disulfide. NMAM Method 1018 for dichlorodifluoromethane uses two coconut-shell charcoal tubes in series, a 400/200-mg tube followed by a 100/50-mg tube, which are desorbed with methylene chloride. This method was evaluated for chlorodifluoromethane. Test atmospheres, with chlorodifluoromethane concentrations from 0.5-2 times the PEL were generated. Modifications of NMAM Method 1018 included changes in the standard preparation procedure, and the gas chromatograph was equipped with a capillary column. These revisions to NMAM 1018 resulted in a 96.5% recovery and a total precision for the method of 7.1% for chlorodifluoromethane. No significant bias in the method was found. Results indicate that the revised NMAM Method 1018 is suitable for the determination of chlorodifluoromethane in workplace air.

  16. Analytical methods for soluble microbial products (SMP) and extracellular polymers (ECP) in wastewater treatment systems: a review.

    PubMed

    Kunacheva, Chinagarn; Stuckey, David C

    2014-09-15

    Effluents from biological processes contain a wide range of complex organic compounds, including soluble microbial products (SMP) and extracellular polymers (ECP), released during bacteria metabolism in mixed culture in bioreactors. It is important to clearly identify the primary components of SMPs and ECPs in order to understand the fundamental mechanisms of biological activity that create these compounds, and how to reduce these compounds in the effluent. In addition, these compounds constitute the main foulants in membrane bioreactors which are being used more widely around the world. A review on the extraction of ECP, characterization, and identification of SMPs and ECPs is presented, and we summarize up-to-date pretreatments and analytical methods for SMPs. Most researchers have focused more on the overall properties of SMPs and ECPs such as their concentrations, molecular weight distribution, aromaticity, hydrophobic and hydrophilic properties, biodegradability, and toxicity characteristics. Many studies on the identification of effluent SMPs show that most of these compounds were not present in the influent, such as humic acids, polysaccharides, proteins, nucleic acids, organic acids, amino acids, exocellular enzymes, structural components of cells and products of energy metabolism. A few groups of researchers have been working on the identification of compounds in SMPs using advanced analytical techniques such as GC-MS, LC-IT-TOF-MS and MALDI-TOF-MS. However, there is still considerably more work needed to be done analytically to fully understand the chemical characteristics of SMPs and ECPs.

  17. Strategy to Promote Active Learning of an Advanced Research Method

    ERIC Educational Resources Information Center

    McDermott, Hilary J.; Dovey, Terence M.

    2013-01-01

    Research methods courses aim to equip students with the knowledge and skills required for research yet seldom include practical aspects of assessment. This reflective practitioner report describes and evaluates an innovative approach to teaching and assessing advanced qualitative research methods to final-year psychology undergraduate students. An…

  18. Combined experimental and analytical study using cruciform specimen for testing advanced aeropropulsion materials under in-plane biaxial loading

    NASA Astrophysics Data System (ADS)

    Abdul-Aziz, Ali; Krause, David

    2006-03-01

    A new in-house test capability has been developed at the NASA Glenn Research Center to conduct highly critical tests in support of major and significant components of the Stirling Radioisotope Generator (SRG). It is to aid the development of analytical life prediction methodology and to experimentally assist in verifying the flight-design component's life. Components within the SRG such as the heater head pressure vessel endure a very high temperature environment for a long period of time. Such conditions impose life-limiting failure by means of material creep, a slow gradual increase in strain which leads to an eventual failure of the pressure vessel. To properly evaluate the performance and assist in the design of this component, testing under multiaxial loading setting is essential, since the heater head is subjected to a biaxial state of stress. Thus, the current work undertakes conducting analytical studies under equibiaxial and non-equi-biaxial loadings situations at various temperatures emulating creep environment. These analytical activities will utilize the finite element method to analyze cruciform type specimens both, under linear elastic and creep conditions. And further to calibrate the in-plane biaxial-test system. The specimen finite element model is generated with MSC/Patran [1] and analytical calculations are conducted with MARC and ANSYS finite element codes [2-3]. Complementing these calculations will undertake conducting experimental tests. However, only results pertaining to the analytical studies are reported and their impact on estimating the life of the component is evaluated.

  19. Experimental design and multiple response optimization. Using the desirability function in analytical methods development.

    PubMed

    Candioti, Luciana Vera; De Zan, María M; Cámara, María S; Goicoechea, Héctor C

    2014-06-01

    A review about the application of response surface methodology (RSM) when several responses have to be simultaneously optimized in the field of analytical methods development is presented. Several critical issues like response transformation, multiple response optimization and modeling with least squares and artificial neural networks are discussed. Most recent analytical applications are presented in the context of analytLaboratorio de Control de Calidad de Medicamentos (LCCM), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, C.C. 242, S3000ZAA Santa Fe, ArgentinaLaboratorio de Control de Calidad de Medicamentos (LCCM), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, C.C. 242, S3000ZAA Santa Fe, Argentinaical methods development, especially in multiple response optimization procedures using the desirability function.

  20. Analytical calculation of spectral phase of grism pairs by the geometrical ray tracing method

    NASA Astrophysics Data System (ADS)

    Rahimi, L.; Askari, A. A.; Saghafifar, H.

    2016-07-01

    The most optimum operation of a grism pair is practically approachable when an analytical expression of its spectral phase is in hand. In this paper, we have employed the accurate geometrical ray tracing method to calculate the analytical phase shift of a grism pair, at transmission and reflection configurations. As shown by the results, for a great variety of complicated configurations, the spectral phase of a grism pair is in the same form of that of a prism pair. The only exception is when the light enters into and exits from different facets of a reflection grism. The analytical result has been used to calculate the second-order dispersions of several examples of grism pairs in various possible configurations. All results are in complete agreement with those from ray tracing method. The result of this work can be very helpful in the optimal design and application of grism pairs at various configurations.

  1. Comparative analysis of methods for real-time analytical control of chemotherapies preparations.

    PubMed

    Bazin, Christophe; Cassard, Bruno; Caudron, Eric; Prognon, Patrice; Havard, Laurent

    2015-10-15

    Control of chemotherapies preparations are now an obligation in France, though analytical control is compulsory. Several methods are available and none of them is presumed as ideal. We wanted to compare them so as to determine which one could be the best choice. We compared non analytical (visual and video-assisted, gravimetric) and analytical (HPLC/FIA, UV/FT-IR, UV/Raman, Raman) methods thanks to our experience and a SWOT analysis. The results of the analysis show great differences between the techniques, but as expected none us them is without defects. However they can probably be used in synergy. Overall for the pharmacist willing to get involved, the implementation of the control for chemotherapies preparations must be widely anticipated, with the listing of every parameter, and remains according to us an analyst's job. PMID:26299761

  2. Design and structural verification of locomotive bogies using combined analytical and experimental methods

    NASA Astrophysics Data System (ADS)

    Manea, I.; Popa, G.; Girnita, I.; Prenta, G.

    2015-11-01

    The paper presents a practical methodology for design and structural verification of the locomotive bogie frames using a modern software package for design, structural verification and validation through combined, analytical and experimental methods. In the initial stage, the bogie geometry is imported from a CAD program into a finite element analysis program, such as Ansys. The analytical model validation is done by experimental modal analysis carried out on a finished bogie frame. The bogie frame own frequencies and own modes by both experimental and analytic methods are determined and the correlation analysis of the two types of models is performed. If the results are unsatisfactory, the structural optimization should be performed. If the results are satisfactory, the qualification procedures follow by static and fatigue tests carried out in a laboratory with international accreditation in the field. This paper presents an application made on bogie frames for the LEMA electric locomotive of 6000 kW.

  3. Transfer-matrix-based method for an analytical description of velocity-map-imaging spectrometers

    NASA Astrophysics Data System (ADS)

    Harb, M. M.; Cohen, S.; Papalazarou, E.; Lépine, F.; Bordas, C.

    2010-12-01

    We propose a simple and general analytical model describing the operation of a velocity-map-imaging spectrometer. We show that such a spectrometer, possibly equipped with a magnifying lens, can be efficiently modeled by combining analytical expressions for the axial potential distributions along with a transfer matrix method. The model leads transparently to the prediction of the instrument's operating conditions as well as to its resolution. A photoelectron velocity-map-imaging spectrometer with a magnifying lens, built and operated along the lines suggested by the model has been successfully employed for recording images at threshold photoionization of atomic lithium. The model's reliability is demonstrated by the fairly good agreement between experimental results and calculations. Finally, the limitations of the analytical method along with possible generalizations, extensions, and potential applications are also discussed. The model may serve as a guide for users interested in building and operating such spectrometers as well as a tutorial tool.

  4. Comparative analysis of methods for real-time analytical control of chemotherapies preparations.

    PubMed

    Bazin, Christophe; Cassard, Bruno; Caudron, Eric; Prognon, Patrice; Havard, Laurent

    2015-10-15

    Control of chemotherapies preparations are now an obligation in France, though analytical control is compulsory. Several methods are available and none of them is presumed as ideal. We wanted to compare them so as to determine which one could be the best choice. We compared non analytical (visual and video-assisted, gravimetric) and analytical (HPLC/FIA, UV/FT-IR, UV/Raman, Raman) methods thanks to our experience and a SWOT analysis. The results of the analysis show great differences between the techniques, but as expected none us them is without defects. However they can probably be used in synergy. Overall for the pharmacist willing to get involved, the implementation of the control for chemotherapies preparations must be widely anticipated, with the listing of every parameter, and remains according to us an analyst's job.

  5. An Overview of Conventional and Emerging Analytical Methods for the Determination of Mycotoxins

    PubMed Central

    Cigić, Irena Kralj; Prosen, Helena

    2009-01-01

    Mycotoxins are a group of compounds produced by various fungi and excreted into the matrices on which they grow, often food intended for human consumption or animal feed. The high toxicity and carcinogenicity of these compounds and their ability to cause various pathological conditions has led to widespread screening of foods and feeds potentially polluted with them. Maximum permissible levels in different matrices have also been established for some toxins. As these are quite low, analytical methods for determination of mycotoxins have to be both sensitive and specific. In addition, an appropriate sample preparation and pre-concentration method is needed to isolate analytes from rather complicated samples. In this article, an overview of methods for analysis and sample preparation published in the last ten years is given for the most often encountered mycotoxins in different samples, mainly in food. Special emphasis is on liquid chromatography with fluorescence and mass spectrometric detection, while in the field of sample preparation various solid-phase extraction approaches are discussed. However, an overview of other analytical and sample preparation methods less often used is also given. Finally, different matrices where mycotoxins have to be determined are discussed with the emphasis on their specific characteristics important for the analysis (human food and beverages, animal feed, biological samples, environmental samples). Various issues important for accurate qualitative and quantitative analyses are critically discussed: sampling and choice of representative sample, sample preparation and possible bias associated with it, specificity of the analytical method and critical evaluation of results. PMID:19333436

  6. Leveraging data analytics, patterning simulations and metrology models to enhance CD metrology accuracy for advanced IC nodes

    NASA Astrophysics Data System (ADS)

    Rana, Narender; Zhang, Yunlin; Kagalwala, Taher; Hu, Lin; Bailey, Todd

    2014-04-01

    Integrated Circuit (IC) technology is changing in multiple ways: 193i to EUV exposure, planar to non-planar device architecture, from single exposure lithography to multiple exposure and DSA patterning etc. Critical dimension (CD) control requirement is becoming stringent and more exhaustive: CD and process window are shrinking., three sigma CD control of < 2 nm is required in complex geometries, and metrology uncertainty of < 0.2 nm is required to achieve the target CD control for advanced IC nodes (e.g. 14 nm, 10 nm and 7 nm nodes). There are fundamental capability and accuracy limits in all the metrology techniques that are detrimental to the success of advanced IC nodes. Reference or physical CD metrology is provided by CD-AFM, and TEM while workhorse metrology is provided by CD-SEM, Scatterometry, Model Based Infrared Reflectrometry (MBIR). Precision alone is not sufficient moving forward. No single technique is sufficient to ensure the required accuracy of patterning. The accuracy of CD-AFM is ~1 nm and precision in TEM is poor due to limited statistics. CD-SEM, scatterometry and MBIR need to be calibrated by reference measurements for ensuring the accuracy of patterned CDs and patterning models. There is a dire need of measurement with < 0.5 nm accuracy and the industry currently does not have that capability with inline measurments. Being aware of the capability gaps for various metrology techniques, we have employed data processing techniques and predictive data analytics, along with patterning simulation and metrology models, and data integration techniques to selected applications demonstrating the potential solution and practicality of such an approach to enhance CD metrology accuracy. Data from multiple metrology techniques has been analyzed in multiple ways to extract information with associated uncertainties and integrated to extract the useful and more accurate CD and profile information of the structures. This paper presents the optimization of

  7. Importance of Genetic Diversity Assessment in Crop Plants and Its Recent Advances: An Overview of Its Analytical Perspectives

    PubMed Central

    Govindaraj, M.; Vetriventhan, M.; Srinivasan, M.

    2015-01-01

    The importance of plant genetic diversity (PGD) is now being recognized as a specific area since exploding population with urbanization and decreasing cultivable lands are the critical factors contributing to food insecurity in developing world. Agricultural scientists realized that PGD can be captured and stored in the form of plant genetic resources (PGR) such as gene bank, DNA library, and so forth, in the biorepository which preserve genetic material for long period. However, conserved PGR must be utilized for crop improvement in order to meet future global challenges in relation to food and nutritional security. This paper comprehensively reviews four important areas; (i) the significance of plant genetic diversity (PGD) and PGR especially on agriculturally important crops (mostly field crops); (ii) risk associated with narrowing the genetic base of current commercial cultivars and climate change; (iii) analysis of existing PGD analytical methods in pregenomic and genomic era; and (iv) modern tools available for PGD analysis in postgenomic era. This discussion benefits the plant scientist community in order to use the new methods and technology for better and rapid assessment, for utilization of germplasm from gene banks to their applied breeding programs. With the advent of new biotechnological techniques, this process of genetic manipulation is now being accelerated and carried out with more precision (neglecting environmental effects) and fast-track manner than the classical breeding techniques. It is also to note that gene banks look into several issues in order to improve levels of germplasm distribution and its utilization, duplication of plant identity, and access to database, for prebreeding activities. Since plant breeding research and cultivar development are integral components of improving food production, therefore, availability of and access to diverse genetic sources will ensure that the global food production network becomes more sustainable

  8. Importance of genetic diversity assessment in crop plants and its recent advances: an overview of its analytical perspectives.

    PubMed

    Govindaraj, M; Vetriventhan, M; Srinivasan, M

    2015-01-01

    The importance of plant genetic diversity (PGD) is now being recognized as a specific area since exploding population with urbanization and decreasing cultivable lands are the critical factors contributing to food insecurity in developing world. Agricultural scientists realized that PGD can be captured and stored in the form of plant genetic resources (PGR) such as gene bank, DNA library, and so forth, in the biorepository which preserve genetic material for long period. However, conserved PGR must be utilized for crop improvement in order to meet future global challenges in relation to food and nutritional security. This paper comprehensively reviews four important areas; (i) the significance of plant genetic diversity (PGD) and PGR especially on agriculturally important crops (mostly field crops); (ii) risk associated with narrowing the genetic base of current commercial cultivars and climate change; (iii) analysis of existing PGD analytical methods in pregenomic and genomic era; and (iv) modern tools available for PGD analysis in postgenomic era. This discussion benefits the plant scientist community in order to use the new methods and technology for better and rapid assessment, for utilization of germplasm from gene banks to their applied breeding programs. With the advent of new biotechnological techniques, this process of genetic manipulation is now being accelerated and carried out with more precision (neglecting environmental effects) and fast-track manner than the classical breeding techniques. It is also to note that gene banks look into several issues in order to improve levels of germplasm distribution and its utilization, duplication of plant identity, and access to database, for prebreeding activities. Since plant breeding research and cultivar development are integral components of improving food production, therefore, availability of and access to diverse genetic sources will ensure that the global food production network becomes more sustainable

  9. Analytical procedures for estimating structural response to acoustic fields generated by advanced launch systems, phase 2

    NASA Technical Reports Server (NTRS)

    Elishakoff, Isaac; Lin, Y. K.; Zhu, Li-Ping; Fang, Jian-Jie; Cai, G. Q.

    1994-01-01

    This report supplements a previous report of the same title submitted in June, 1992. It summarizes additional analytical techniques which have been developed for predicting the response of linear and nonlinear structures to noise excitations generated by large propulsion power plants. The report is divided into nine chapters. The first two deal with incomplete knowledge of boundary conditions of engineering structures. The incomplete knowledge is characterized by a convex set, and its diagnosis is formulated as a multi-hypothesis discrete decision-making algorithm with attendant criteria of adaptive termination.

  10. Analytical investigation of thermal barrier coatings for advanced power generation combustion turbines

    NASA Technical Reports Server (NTRS)

    Amos, D. J.

    1977-01-01

    An analytical evaluation was conducted to determine quantitatively the improvement potential in cycle efficiency and cost of electricity made possible by the introduction of thermal barrier coatings to power generation combustion turbine systems. The thermal barrier system, a metallic bond coat and yttria stabilized zirconia outer layer applied by plasma spray techniques, acts as a heat insulator to provide substantial metal temperature reductions below that of the exposed thermal barrier surface. The study results show the thermal barrier to be a potentially attractive means for improving performance and reducing cost of electricity for the simple, recuperated, and combined cycles evaluated.

  11. Advanced Analytic Treatment and Efficient Computation of the Diffraction Integrals in the Extended Nijboer-Zernike Theory

    NASA Astrophysics Data System (ADS)

    van Haver, S.; Janssen, A. J. E. M.

    2013-07-01

    The computational methods for the diffraction integrals that occur in the Extended Nijboer-Zernike (ENZ-) approach to circular, aberrated, defocused optical systems are reviewed and updated. In the ENZ-approach, the Debye approximation of Rayleigh's integral for the through-focus, complex, point-spread function is evaluated in semi-analytic form. To this end, the generalized pupil function, comprising phase aberrations as well as amplitude non-uniformities, is assumed to be expanded into a series of Zernike circle polynomials, and the contribution of each of these Zernike terms to the diffraction integral is expressed in the form of a rapidly converging series (containing power functions and/or Bessel functions of various kinds). The procedure of expressing the through-focus point-spread function in terms of Zernike expansion coefficients of the pupil function can be reversed and has led to the ENZ-method of retrieval of pupil functions from measured through-focus (inte! nsity) point-spread functions. The review and update concern the computation for systems ranging from as basic as having low NA and small defocus parameter to high-NA systems, with vector fields and polarization, meant for imaging of extended objects into a multi-layered focal region. In the period 2002-2010, the evolution of the form of the diffraction integral (DI) was dictated by the agenda of the ENZ-team in which a next instance of the DI was handled by amending the computation scheme of the previous one. This has resulted into a variety of ad hoc measures, lack of transparency of the schemes, and sometimes prohibitively slow computer codes. It is the aim of the present paper to reconstruct the whole building of computation methods, using consistently more advanced mathematical tools. These tools are -explicit Zernike expansion of the focal factor in the DI, -Clebsch-Gordan coefficients for the omnipresent problem of linearizing products ofZernike circle polynomials, -recursions for Bessel

  12. A Primer In Advanced Fatigue Life Prediction Methods

    NASA Technical Reports Server (NTRS)

    Halford, Gary R.

    2000-01-01

    Metal fatigue has plagued structural components for centuries, and it remains a critical durability issue in today's aerospace hardware. This is true despite vastly improved and advanced materials, increased mechanistic understanding, and development of accurate structural analysis and advanced fatigue life prediction tools. Each advance is quickly taken advantage of to produce safer, more reliable more cost effective, and better performing products. In other words, as the envelop is expanded, components are then designed to operate just as close to the newly expanded envelop as they were to the initial one. The problem is perennial. The economic importance of addressing structural durability issues early in the design process is emphasized. Tradeoffs with performance, cost, and legislated restrictions are pointed out. Several aspects of structural durability of advanced systems, advanced materials and advanced fatigue life prediction methods are presented. Specific items include the basic elements of durability analysis, conventional designs, barriers to be overcome for advanced systems, high-temperature life prediction for both creep-fatigue and thermomechanical fatigue, mean stress effects, multiaxial stress-strain states, and cumulative fatigue damage accumulation assessment.

  13. Calibration coefficient of reference brachytherapy ionization chamber using analytical and Monte Carlo methods.

    PubMed

    Kumar, Sudhir; Srinivasan, P; Sharma, S D

    2010-06-01

    A cylindrical graphite ionization chamber of sensitive volume 1002.4 cm(3) was designed and fabricated at Bhabha Atomic Research Centre (BARC) for use as a reference dosimeter to measure the strength of high dose rate (HDR) (192)Ir brachytherapy sources. The air kerma calibration coefficient (N(K)) of this ionization chamber was estimated analytically using Burlin general cavity theory and by the Monte Carlo method. In the analytical method, calibration coefficients were calculated for each spectral line of an HDR (192)Ir source and the weighted mean was taken as N(K). In the Monte Carlo method, the geometry of the measurement setup and physics related input data of the HDR (192)Ir source and the surrounding material were simulated using the Monte Carlo N-particle code. The total photon energy fluence was used to arrive at the reference air kerma rate (RAKR) using mass energy absorption coefficients. The energy deposition rates were used to simulate the value of charge rate in the ionization chamber and N(K) was determined. The Monte Carlo calculated N(K) agreed within 1.77 % of that obtained using the analytical method. The experimentally determined RAKR of HDR (192)Ir sources, using this reference ionization chamber by applying the analytically estimated N(K), was found to be in agreement with the vendor quoted RAKR within 1.43%.

  14. 40 CFR 260.21 - Petitions for equivalent testing or analytical methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Petitions for equivalent testing or analytical methods. 260.21 Section 260.21 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) HAZARDOUS WASTE MANAGEMENT SYSTEM: GENERAL Rulemaking Petitions §...

  15. Knowledge, Skills, and Abilities for Entry-Level Business Analytics Positions: A Multi-Method Study

    ERIC Educational Resources Information Center

    Cegielski, Casey G.; Jones-Farmer, L. Allison

    2016-01-01

    It is impossible to deny the significant impact from the emergence of big data and business analytics on the fields of Information Technology, Quantitative Methods, and the Decision Sciences. Both industry and academia seek to hire talent in these areas with the hope of developing organizational competencies. This article describes a multi-method…

  16. COMPARISON OF ANALYTICAL METHODS FOR THE MEASUREMENT OF NON-VIABLE BIOLOGICAL PM

    EPA Science Inventory

    The paper describes a preliminary research effort to develop a methodology for the measurement of non-viable biologically based particulate matter (PM), analyzing for mold, dust mite, and ragweed antigens and endotoxins. Using a comparison of analytical methods, the research obj...

  17. Meta-Analytic Structural Equation Modeling (MASEM): Comparison of the Multivariate Methods

    ERIC Educational Resources Information Center

    Zhang, Ying

    2011-01-01

    Meta-analytic Structural Equation Modeling (MASEM) has drawn interest from many researchers recently. In doing MASEM, researchers usually first synthesize correlation matrices across studies using meta-analysis techniques and then analyze the pooled correlation matrix using structural equation modeling techniques. Several multivariate methods of…

  18. Addressing fundamental architectural challenges of an activity-based intelligence and advanced analytics (ABIAA) system

    NASA Astrophysics Data System (ADS)

    Yager, Kevin; Albert, Thomas; Brower, Bernard V.; Pellechia, Matthew F.

    2015-06-01

    The domain of Geospatial Intelligence Analysis is rapidly shifting toward a new paradigm of Activity Based Intelligence (ABI) and information-based Tipping and Cueing. General requirements for an advanced ABIAA system present significant challenges in architectural design, computing resources, data volumes, workflow efficiency, data mining and analysis algorithms, and database structures. These sophisticated ABI software systems must include advanced algorithms that automatically flag activities of interest in less time and within larger data volumes than can be processed by human analysts. In doing this, they must also maintain the geospatial accuracy necessary for cross-correlation of multi-intelligence data sources. Historically, serial architectural workflows have been employed in ABIAA system design for tasking, collection, processing, exploitation, and dissemination. These simpler architectures may produce implementations that solve short term requirements; however, they have serious limitations that preclude them from being used effectively in an automated ABIAA system with multiple data sources. This paper discusses modern ABIAA architectural considerations providing an overview of an advanced ABIAA system and comparisons to legacy systems. It concludes with a recommended strategy and incremental approach to the research, development, and construction of a fully automated ABIAA system.

  19. Advanced stress analysis methods applicable to turbine engine structures

    NASA Technical Reports Server (NTRS)

    Pian, T. H. H.

    1985-01-01

    Advanced stress analysis methods applicable to turbine engine structures are investigated. Constructions of special elements which containing traction-free circular boundaries are investigated. New versions of mixed variational principle and version of hybrid stress elements are formulated. A method is established for suppression of kinematic deformation modes. semiLoof plate and shell elements are constructed by assumed stress hybrid method. An elastic-plastic analysis is conducted by viscoplasticity theory using the mechanical subelement model.

  20. Advanced surface paneling method for subsonic and supersonic flow

    NASA Technical Reports Server (NTRS)

    Erickson, L. L.; Johnson, F. T.; Ehlers, F. E.

    1976-01-01

    Numerical results illustrating the capabilities of an advanced aerodynamic surface paneling method are presented. The method is applicable to both subsonic and supersonic flow, as represented by linearized potential flow theory. The method is based on linearly varying sources and quadratically varying doublets which are distributed over flat or curved panels. These panels are applied to the true surface geometry of arbitrarily shaped three dimensional aerodynamic configurations.

  1. A minireview of analytical methods for the geographical origin analysis of teas (Camellia sinensis).

    PubMed

    Ye, N S

    2012-01-01

    Chemical compositions in tea leaves are influenced by their growing surrounding, and the content of these components are related to the quality of teas. The determination of the concentration of chemical composition in teas will predict the ranking of teas and indicate the geographical origins. This overview concerns an investigation of analytical methods that are being used for the determination of the geographical origin of tea. The analytical approaches have been subdivided into three groups: spectroscopic techniques, chromatographic techniques, and other techniques. The advantages, drawbacks, and reported applications concerning geographical authenticity are discussed.

  2. Reconceptualizing vulnerability: deconstruction and reconstruction as a postmodern feminist analytical research method.

    PubMed

    Glass, Nel; Davis, Kierrynn

    2004-01-01

    Nursing research informed by postmodern feminist perspectives has prompted many debates in recent times. While this is so, nurse researchers who have been tempted to break new ground have had few examples of appropriate analytical methods for a research design informed by the above perspectives. This article presents a deconstructive/reconstructive secondary analysis of a postmodern feminist ethnography in order to provide an analytical exemplar. In doing so, previous notions of vulnerability as a negative state have been challenged and reconstructed. PMID:15206680

  3. Protein Microarrays with Novel Microfluidic Methods: Current Advances

    PubMed Central

    Dixit, Chandra K.; Aguirre, Gerson R.

    2014-01-01

    Microfluidic-based micromosaic technology has allowed the pattering of recognition elements in restricted micrometer scale areas with high precision. This controlled patterning enabled the development of highly multiplexed arrays multiple analyte detection. This arraying technology was first introduced in the beginning of 2001 and holds tremendous potential to revolutionize microarray development and analyte detection. Later, several microfluidic methods were developed for microarray application. In this review we discuss these novel methods and approaches which leverage the property of microfluidic technologies to significantly improve various physical aspects of microarray technology, such as enhanced imprinting homogeneity, stability of the immobilized biomolecules, decreasing assay times, and reduction of the costs and of the bulky instrumentation. PMID:27600343

  4. Synthetic cathinone pharmacokinetics, analytical methods, and toxicological findings from human performance and postmortem cases.

    PubMed

    Ellefsen, Kayla N; Concheiro, Marta; Huestis, Marilyn A

    2016-05-01

    Synthetic cathinones are commonly abused novel psychoactive substances (NPS). We present a comprehensive systematic review addressing in vitro and in vivo synthetic cathinone pharmacokinetics, analytical methods for detection and quantification in biological matrices, and toxicological findings from human performance and postmortem toxicology cases. Few preclinical administration studies examined synthetic cathinone pharmacokinetic profiles (absorption, distribution, metabolism, and excretion), and only one investigated metabolite pharmacokinetics. Synthetic cathinone metabolic profiling studies, primarily with human liver microsomes, elucidated metabolite structures and identified suitable biomarkers to extend detection windows beyond those provided by parent compounds. Generally, cathinone derivatives underwent ketone reduction, carbonylation of the pyrrolidine ring, and oxidative reactions, with phase II metabolites also detected. Reliable analytical methods are necessary for cathinone identification in biological matrices to document intake and link adverse events to specific compounds and concentrations. NPS analytical methods are constrained in their ability to detect new emerging synthetic cathinones due to limited commercially available reference standards and continuous development of new analogs. Immunoassay screening methods are especially affected, but also gas-chromatography and liquid-chromatography mass spectrometry confirmation methods. Non-targeted high-resolution-mass spectrometry screening methods are advantageous, as they allow for retrospective data analysis and easier addition of new synthetic cathinones to existing methods. Lack of controlled administration studies in humans complicate interpretation of synthetic cathinones in biological matrices, as dosing information is typically unknown. Furthermore, antemortem and postmortem concentrations often overlap and the presence of other psychoactive substances are typically found in combination

  5. Evaluation Methodology for Advance Heat Exchanger Concepts Using Analytical Hierarchy Process

    SciTech Connect

    Piyush Sabharwall; Eung Soo Kim

    2012-07-01

    The primary purpose of this study is to aid in the development and selection of the secondary/process heat exchanger (SHX) for power production and process heat application for a Next Generation Nuclear Reactors (NGNR). The potential options for use as an SHX are explored such as shell and tube, printed circuit heat exchanger. A shell and tube (helical coiled) heat exchanger is a recommended for a demonstration reactor because of its reliability while the reactor design is being further developed. The basic setup for the selection of the SHX has been established with evaluation goals, alternatives, and criteria. This study describes how these criteria and the alternatives are evaluated using the analytical hierarchy process (AHP).

  6. A simple analytical method for heterogeneity corrections in low dose rate prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Hueso-González, Fernando; Vijande, Javier; Ballester, Facundo; Perez-Calatayud, Jose; Siebert, Frank-André

    2015-07-01

    In low energy brachytherapy, the presence of tissue heterogeneities contributes significantly to the discrepancies observed between treatment plan and delivered dose. In this work, we present a simplified analytical dose calculation algorithm for heterogeneous tissue. We compare it with Monte Carlo computations and assess its suitability for integration in clinical treatment planning systems. The algorithm, named as RayStretch, is based on the classic equivalent path length method and TG-43 reference data. Analytical and Monte Carlo dose calculations using Penelope2008 are compared for a benchmark case: a prostate patient with calcifications. The results show a remarkable agreement between simulation and algorithm, the latter having, in addition, a high calculation speed. The proposed analytical model is compatible with clinical real-time treatment planning systems based on TG-43 consensus datasets for improving dose calculation and treatment quality in heterogeneous tissue. Moreover, the algorithm is applicable for any type of heterogeneities.

  7. Homotopy Perturbation Method-Based Analytical Solution for Tide-Induced Groundwater Fluctuations.

    PubMed

    Munusamy, Selva Balaji; Dhar, Anirban

    2016-05-01

    The groundwater variations in unconfined aquifers are governed by the nonlinear Boussinesq's equation. Analytical solution for groundwater fluctuations in coastal aquifers under tidal forcing can be solved using perturbation methods. However, the perturbation parameters should be properly selected and predefined for traditional perturbation methods. In this study, a new dimensional, higher-order analytical solution for groundwater fluctuations is proposed by using the homotopy perturbation method with a virtual perturbation parameter. Parameter-expansion method is used to remove the secular terms generated during the solution process. The solution does not require any predefined perturbation parameter and valid for higher values of amplitude parameter A/D, where A is the amplitude of the tide and D is the aquifer thickness.

  8. Analytical method for analyzing c-channel stiffener made of laminate composite

    NASA Astrophysics Data System (ADS)

    Kumton, Tattchapong

    Composite materials play the important role in the aviation industry. Conventional materials such as aluminum were replaced by composite material on the main structures. The objective of this study focuses on development of analytical method to analyze the laminated composite structure with C-channel cross-section. A lamination theory base closed-form solution was developed to analysis ply stresses on the C-channel cross-section. The developed method contains the effects of coupling due to unsymmetrical of both laminate and structural configuration levels. The present method also included the expression of the sectional properties such as centroid, axial and bending stiffnesses of cross-section. The results obtain from analytical method showed an excellent agreement with finite element results.

  9. Dynamic buckling analysis of delaminated composite plates using semi-analytical finite strip method

    NASA Astrophysics Data System (ADS)

    Ovesy, H. R.; Totounferoush, A.; Ghannadpour, S. A. M.

    2015-05-01

    The delamination phenomena can become of paramount importance when the design of the composite plates is concerned. In the current study, the effect of through-the-width delamination on dynamic buckling behavior of a composite plate is studied by implementing semi-analytical finite strip method. In this method, the energy and work integrations are computed analytically due to the implementation of trigonometric functions. Moreover, the method can lead to converged results with comparatively small number of degrees of freedom. These features have made the method quite efficient. To account for delamination effects, displacement field is enriched by adding appropriate terms. Also, the penetration of the delamination surfaces is prevented by incorporating an appropriate contact scheme into the time response analysis. Some selected results are validated against those available in the literature.

  10. Analytical Method for Reduction of Residual Stress Using Low Frequency and Ultrasonic Vibrations

    NASA Astrophysics Data System (ADS)

    Aoki, Shigeru; Kurita, Katsumi; Koshimizu, Shigeomi; Nishimura, Tadashi; Hiroi, Tetsumaro; Hirai, Seiji

    Welding is widely used for construction of many structures. It is well known that residual stress is generated near the bead because of locally given heat. Tensile residual stress on the surface degrades fatigue strength. On the other hand, welding is used for repair of mold and die. In this case, reduction of residual stress is required because of protection from crack of welded part in mold and die. In this paper, a new method for reduction of residual stress of welded joint is proposed for repair welding of mold and die. In this method, low frequency and ultrasonic vibrations are used during welding. Thick plates are used as specimens of mold and die. Residual stresses are reduced when low frequency and ultrasonic vibrations are used during welding. Experimental results are examined by simulation method using an analytical model. One mass model considering plastic deformation is used as an analytical model. Experimental results are demonstrated by simulation method.

  11. Advanced digital methods for solid propellant burning rate determination

    NASA Astrophysics Data System (ADS)

    Jones, Daniel A.

    The work presented here is a study of a digital method for determining the combustion bomb burning rate of a fuel-rich gas generator propellant sample using the ultrasonic pulse-echo technique. The advanced digital method, which places user defined limits on the search for the ultrasonic echo from the burning surface, is computationally faster than the previous cross correlation method, and is able to analyze data for this class of propellant that the previous cross correlation data reduction method could not. For the conditions investigated, the best fit burning rate law at 800 psi from the ultrasonic technique and advanced cross correlation method is within 3 percent of an independent analysis of the same data, and is within 5 percent of the best fit burning rate law found from parallel research of the same propellant in a motor configuration.

  12. Recent advances in optical measurement methods in physics and chemistry

    SciTech Connect

    Gerardo, J.B.

    1985-01-01

    Progress being made in the development of new scientific measurement tools based on optics and the scientific advances made possible by these new tools is impressive. In some instances, new optical-based measurement methods have made new scientific studies possible, while in other instances they have offered an improved method for performing these studies, e.g., better signal-to-noise ratio, increased data acquisition rate, remote analysis, reduced perturbation to the physical or chemical system being studied, etc. Many of these advances were made possible by advances in laser technology - spectral purity, spectral brightness, tunability, ultrashort pulse width, amplitude stability, etc. - while others were made possible by improved optical components - single-made fibers, modulators, detectors, wavelength multiplexes, etc. Attention is limited to just a few of many such accomplishments made recently at Sandia. 17 references, 16 figures.

  13. Status report on analytical methods to support the disinfectant/disinfection by-products regulation

    SciTech Connect

    Not Available

    1992-08-01

    The U.S. EPA is developng national regulations to control disinfectants and disinfection by-products in public drinking water supplies. Twelve disinfectants and disinfection by-products are identified for possible regulation under this rule. The document summarizes the analytical methods that EPA intends to propose as compliance monitoring methods. A discussion of surrogate measurements that are being considered for inclusion in the regulation is also provided.

  14. Flight and Analytical Methods for Determining the Coupled Vibration Response of Tandem Helicopters

    NASA Technical Reports Server (NTRS)

    Yeates, John E , Jr; Brooks, George W; Houbolt, John C

    1957-01-01

    Chapter one presents a discussion of flight-test and analysis methods for some selected helicopter vibration studies. The use of a mechanical shaker in flight to determine the structural response is reported. A method for the analytical determination of the natural coupled frequencies and mode shapes of vibrations in the vertical plane of tandem helicopters is presented in Chapter two. The coupled mode shapes and frequencies are then used to calculate the response of the helicopter to applied oscillating forces.

  15. On the Use of Accelerated Test Methods for Characterization of Advanced Composite Materials

    NASA Technical Reports Server (NTRS)

    Gates, Thomas S.

    2003-01-01

    A rational approach to the problem of accelerated testing for material characterization of advanced polymer matrix composites is discussed. The experimental and analytical methods provided should be viewed as a set of tools useful in the screening of material systems for long-term engineering properties in aerospace applications. Consideration is given to long-term exposure in extreme environments that include elevated temperature, reduced temperature, moisture, oxygen, and mechanical load. Analytical formulations useful for predictive models that are based on the principles of time-based superposition are presented. The need for reproducible mechanisms, indicator properties, and real-time data are outlined as well as the methodologies for determining specific aging mechanisms.

  16. Implicit solution of Navier-Stokes equations on staggered curvilinear grids using a Newton-Krylov method with a novel analytical Jacobian.

    NASA Astrophysics Data System (ADS)

    Borazjani, Iman; Asgharzadeh, Hafez

    2015-11-01

    Flow simulations involving complex geometries and moving boundaries suffer from time-step size restriction and low convergence rates with explicit and semi-implicit schemes. Implicit schemes can be used to overcome these restrictions. However, implementing implicit solver for nonlinear equations including Navier-Stokes is not straightforward. Newton-Krylov subspace methods (NKMs) are one of the most advanced iterative methods to solve non-linear equations such as implicit descritization of the Navier-Stokes equation. The efficiency of NKMs massively depends on the Jacobian formation method, e.g., automatic differentiation is very expensive, and matrix-free methods slow down as the mesh is refined. Analytical Jacobian is inexpensive method, but derivation of analytical Jacobian for Navier-Stokes equation on staggered grid is challenging. The NKM with a novel analytical Jacobian was developed and validated against Taylor-Green vortex and pulsatile flow in a 90 degree bend. The developed method successfully handled the complex geometries such as an intracranial aneurysm with multiple overset grids, and immersed boundaries. It is shown that the NKM with an analytical Jacobian is 3 to 25 times faster than the fixed-point implicit Runge-Kutta method, and more than 100 times faster than automatic differentiation depending on the grid (size) and the flow problem. The developed methods are fully parallelized with parallel efficiency of 80-90% on the problems tested.

  17. Effect-Based Screening Methods for Water Quality Characterization Will Augment Conventional Analyte-by-Analyte Chemical Methods in Research As Well As Regulatory Monitoring

    EPA Science Inventory

    Conventional approaches to water quality characterization can provide data on individual chemical components of each water sample. This analyte-by-analyte approach currently serves many useful research and compliance monitoring needs. However these approaches, which require a ...

  18. 7 CFR 27.92 - Method of payment; advance deposit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Method of payment; advance deposit. 27.92 Section 27.92 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE COMMODITY STANDARDS AND STANDARD...

  19. METHODS ADVANCEMENT FOR MILK ANALYSIS: THE MAMA STUDY

    EPA Science Inventory

    The Methods Advancement for Milk Analysis (MAMA) study was designed by US EPA and CDC investigators to provide data to support the technological and study design needs of the proposed National Children=s Study (NCS). The NCS is a multi-Agency-sponsored study, authorized under the...

  20. Advanced propulsion for LEO-Moon transport. 1: A method for evaluating advanced propulsion performance

    NASA Technical Reports Server (NTRS)

    Stern, Martin O.

    1992-01-01

    This report describes a study to evaluate the benefits of advanced propulsion technologies for transporting materials between low Earth orbit and the Moon. A relatively conventional reference transportation system, and several other systems, each of which includes one advanced technology component, are compared in terms of how well they perform a chosen mission objective. The evaluation method is based on a pairwise life-cycle cost comparison of each of the advanced systems with the reference system. Somewhat novel and economically important features of the procedure are the inclusion not only of mass payback ratios based on Earth launch costs, but also of repair and capital acquisition costs, and of adjustments in the latter to reflect the technological maturity of the advanced technologies. The required input information is developed by panels of experts. The overall scope and approach of the study are presented in the introduction. The bulk of the paper describes the evaluation method; the reference system and an advanced transportation system, including a spinning tether in an eccentric Earth orbit, are used to illustrate it.

  1. An analytical method of ultra-trace tellurium for samples of sea- and environmental-water.

    PubMed

    Jingru, A; Qing, Z

    1983-01-01

    This paper presents a method for the concentration of tellurium in sulfhydral cotton fiber. The mechanism of Te-Re catalytic polarographic behaviour has been studied. The optimal conditions of systems are proposed. An analytical procedure of preconcentration with sulfhydral cotton fiber and catalytic polarographic determination of ultra-trace tellurium is presented. This method exhibits good selectivity and is simple and easy. It is also one o;f the most sensitive analytical methods of tellurium at present. The procedure is demonstrated successfully for the determination of background levels of tellurium in a variety of natural water. This is the first reported determination of tellurium in sea water, filling a gap in the literature of oceanic geochemistry. It was found that the content of tellurium in South China sea water is 8 X 10(-10) g/l, that in East China sea water is 4-7 X 10(-10) g/l.

  2. Trigonometric and hyperbolic functions method for constructing analytic solutions to nonlinear plane magnetohydrodynamics equilibrium equations

    SciTech Connect

    Moawad, S. M.

    2015-02-15

    In this paper, we present a solution method for constructing exact analytic solutions to magnetohydrodynamics (MHD) equations. The method is constructed via all the trigonometric and hyperbolic functions. The method is applied to MHD equilibria with mass flow. Applications to a solar system concerned with the properties of coronal mass ejections that affect the heliosphere are presented. Some examples of the constructed solutions which describe magnetic structures of solar eruptions are investigated. Moreover, the constructed method can be applied to a variety classes of elliptic partial differential equations which arise in plasma physics.

  3. Semi analytical solution of second order fuzzy Riccati equation by homotopy perturbation method

    NASA Astrophysics Data System (ADS)

    Jameel, A. F.; Ismail, Ahmad Izani Md

    2014-07-01

    In this work, the Homotopy Perturbation Method (HPM) is formulated to find a semi-analytical solution of the Fuzzy Initial Value Problem (FIVP) involving nonlinear second order Riccati equation. This method is based upon homotopy perturbation theory. This method allows for the solution of the differential equation to be calculated in the form of an infinite series in which the components can be easily calculated. The effectiveness of the algorithm is demonstrated by solving nonlinear second order fuzzy Riccati equation. The results indicate that the method is very effective and simple to apply.

  4. An analytic method to account for drag in the Vinti satellite theory. [computer program using quadrature algorithm

    NASA Technical Reports Server (NTRS)

    Watson, J. S.; Mistretta, G. D.; Bonavito, N. L.

    1975-01-01

    A quadrature algorithm is presented which employs analytical expressions for the variations of satellite orbital elements caused by air drag. The Hamiltonian is formally preserved and the Jacobi constants of the motion are advanced with time through the variational equations. The atmospheric density profile is written as a fitted exponential function of the eccentric anomaly, which adheres to tabulated data at all altitudes and simultaneously reduces the variational equations to definite integrals with closed form evaluations, whose limits are in terms of the eccentric anomaly. Results are given for two intense air drag satellites and indicate that the satellite ephemerides produced by this method in conjunction with the Vinti program are of very high accuracy.

  5. Advanced qualification of pharmaceutical excipient suppliers by multiple analytics and multivariate analysis combined.

    PubMed

    Hertrampf, A; Müller, H; Menezes, J C; Herdling, T

    2015-11-10

    Pharmaceutical excipients have different functions within a drug formulation, consequently they can influence the manufacturability and/or performance of medicinal products. Therefore, critical to quality attributes should be kept constant. Sometimes it may be necessary to qualify a second supplier, but its product will not be completely equal to the first supplier product. To minimize risks of not detecting small non-similarities between suppliers and to detect lot-to-lot variability for each supplier, multivariate data analysis (MVA) can be used as a more powerful alternative to classical quality control that uses one-parameter-at-a-time monitoring. Such approach is capable of supporting the requirements of a new guideline by the European Parliament and Council (2015/C-95/02) demanding appropriate quality control strategies for excipients based on their criticality and supplier risks in ensuring quality, safety and function. This study compares calcium hydrogen phosphate from two suppliers. It can be assumed that both suppliers use different manufacturing processes. Therefore, possible chemical and physical differences were investigated by using Raman spectroscopy, laser diffraction and X-ray powder diffraction. Afterwards MVA was used to extract relevant information from each analytical technique. Both CaHPO4 could be discriminated by their supplier. The gained knowledge allowed to specify an enhanced strategy for second supplier qualification.

  6. Advances and future directions of research on spectral methods

    NASA Technical Reports Server (NTRS)

    Patera, A. T.

    1986-01-01

    Recent advances in spectral methods are briefly reviewed and characterized with respect to their convergence and computational complexity. Classical finite element and spectral approaches are then compared, and spectral element (or p-type finite element) approximations are introduced. The method is applied to the full Navier-Stokes equations, and examples are given of the application of the technique to several transitional flows. Future directions of research in the field are outlined.

  7. Two Approaches in the Lunar Libration Theory: Analytical vs. Numerical Methods

    NASA Astrophysics Data System (ADS)

    Petrova, Natalia; Zagidullin, Arthur; Nefediev, Yurii; Kosulin, Valerii

    2016-10-01

    Observation of the physical libration of the Moon and the celestial bodies is one of the astronomical methods to remotely evaluate the internal structure of a celestial body without using expensive space experiments. Review of the results obtained due to the physical libration study, is presented in the report.The main emphasis is placed on the description of successful lunar laser ranging for libration determination and on the methods of simulating the physical libration. As a result, estimation of the viscoelastic and dissipative properties of the lunar body, of the lunar core parameters were done. The core's existence was confirmed by the recent reprocessing of seismic data Apollo missions. Attention is paid to the physical interpretation of the phenomenon of free libration and methods of its determination.A significant part of the report is devoted to describing the practical application of the most accurate to date the analytical tables of lunar libration built by comprehensive analytical processing of residual differences obtained when comparing the long-term series of laser observations with numerical ephemeris DE421 [1].In general, the basic outline of the report reflects the effectiveness of two approaches in the libration theory - numerical and analytical solution. It is shown that the two approaches complement each other for the study of the Moon in different aspects: numerical approach provides high accuracy of the theory necessary for adequate treatment of modern high-accurate observations and the analytic approach allows you to see the essence of the various kind manifestations in the lunar rotation, predict and interpret the new effects in observations of physical libration [2].[1] Rambaux, N., J. G. Williams, 2011, The Moon's physical librations and determination of their free modes, Celest. Mech. Dyn. Astron., 109, 85–100.[2] Petrova N., A. Zagidullin, Yu. Nefediev. Analysis of long-periodic variations of lunar libration parameters on the basis

  8. Recent advances in chemical functionalization of nanoparticles with biomolecules for analytical applications.

    PubMed

    Oh, Ju-Hwan; Park, Do Hyun; Joo, Jang Ho; Lee, Jae-Seung

    2015-11-01

    The recent synthetic development of a variety of nanoparticles has led to their widespread application in diagnostics and therapeutics. In particular, the controlled size and shape of nanoparticles precisely determine their unique chemical and physical properties, which is highly attractive for accurate analysis of given systems. In addition to efforts toward controlling the synthesis and properties of nanoparticles, the surface functionalization of nanoparticles with biomolecules has been intensively investigated since the mid-1990s. The complicated yet programmable properties of biomolecules have proved to substantially enhance and enrich the novel functions of nanoparticles to achieve "smart" nanoparticle materials. In this review, the advances in chemical functionalization of four types of representative nanoparticle with DNA and protein molecules in the past five years are critically reviewed, and their future trends are predicted.

  9. Simultaneous determination of antazoline and naphazoline by the net analyte signal standard addition method and spectrophotometric technique.

    PubMed

    Asadpour-Zeynali, Karim; Ghavami, Raoof; Esfandiari, Roghayeh; Soheili-Azad, Payam

    2010-01-01

    A novel net analyte signal standard addition method (NASSAM) was used for simultaneous determination of the drugs anthazoline and naphazoline. The NASSAM can be applied for determination of analytes in the presence of known interferents. The proposed method is used to eliminate the calibration and prediction steps of multivariate calibration methods; the determination is carried out in a single step for each analyte. The accuracy of the predictions against the H-point standard addition method is independent of the shape of the analyte and interferent spectra. The net analyte signal concept was also used to calculate multivariate analytical figures of merit, such as LOD, selectivity, and sensitivity. The method was successfully applied to the simultaneous determination of anthazoline and naphazoline in a commercial eye drop sample.

  10. Advanced analytical techniques for the extraction and characterization of plant-derived essential oils by gas chromatography with mass spectrometry.

    PubMed

    Waseem, Rabia; Low, Kah Hin

    2015-02-01

    In recent years, essential oils have received a growing interest because of the positive health effects of their novel characteristics such as antibacterial, antifungal, and antioxidant activities. For the extraction of plant-derived essential oils, there is the need of advanced analytical techniques and innovative methodologies. An exhaustive study of hydrodistillation, supercritical fluid extraction, ultrasound- and microwave-assisted extraction, solid-phase microextraction, pressurized liquid extraction, pressurized hot water extraction, liquid-liquid extraction, liquid-phase microextraction, matrix solid-phase dispersion, and gas chromatography (one- and two-dimensional) hyphenated with mass spectrometry for the extraction through various plant species and analysis of essential oils has been provided in this review. Essential oils are composed of mainly terpenes and terpenoids with low-molecular-weight aromatic and aliphatic constituents that are particularly important for public health.

  11. [Recent advances in sample preparation methods of plant hormones].

    PubMed

    Wu, Qian; Wang, Lus; Wu, Dapeng; Duan, Chunfeng; Guan, Yafeng

    2014-04-01

    Plant hormones are a group of naturally occurring trace substances which play a crucial role in controlling the plant development, growth and environment response. With the development of the chromatography and mass spectroscopy technique, chromatographic analytical method has become a widely used way for plant hormone analysis. Among the steps of chromatographic analysis, sample preparation is undoubtedly the most vital one. Thus, a highly selective and efficient sample preparation method is critical for accurate identification and quantification of phytohormones. For the three major kinds of plant hormones including acidic plant hormones & basic plant hormones, brassinosteroids and plant polypeptides, the sample preparation methods are reviewed in sequence especially the recently developed methods. The review includes novel methods, devices, extractive materials and derivative reagents for sample preparation of phytohormones analysis. Especially, some related works of our group are included. At last, the future developments in this field are also prospected.

  12. Advances in spectroscopic methods for quantifying soil carbon

    USGS Publications Warehouse

    Liebig, Mark; Franzluebbers, Alan J.; Follett, Ronald F.; Hively, W. Dean; Reeves, James B.; McCarty, Gregory W.; Calderon, Francisco

    2012-01-01

    The gold standard for soil C determination is combustion. However, this method requires expensive consumables, is limited to the determination of the total carbon and in the number of samples which can be processed (~100/d). With increased interest in soil C sequestration, faster methods are needed. Thus, interest in methods based on diffuse reflectance spectroscopy in the visible, near-infrared or mid-infrared ranges using either proximal or remote sensing. These methods have the ability to analyze more samples (2 to 3X/d) or huge areas (imagery) and do multiple analytes simultaneously, but require calibrations relating spectral and reference data and have specific problems, i.e., remote sensing is capable of scanning entire watersheds, thus reducing the sampling needed, but is limiting to the surface layer of tilled soils and by difficulty in obtaining proper calibration reference values. The objective of this discussion is the present state of spectroscopic methods for soil C determination.

  13. Advances in analytical methodology for bioinorganic speciation analysis: metallomics, metalloproteomics and heteroatom-tagged proteomics and metabolomics.

    PubMed

    Szpunar, Joanna

    2005-04-01

    The recent developments in analytical techniques capable of providing information on the identity and quantity of heteroatom-containing biomolecules are critically discussed. Particular attention is paid to the emerging areas of bioinorganic analysis including: (i) a comprehensive analysis of the entirety of metal and metalloid species within a cell or tissue type (metallomics), (ii) the study of the part of the metallome involving the protein ligands (metalloproteomics), and (iii) the use of a heteroelement, naturally present in a protein or introduced in a tag added by means of derivatisation, for the spotting and quantification of proteins (heteroatom-tagged proteomics). Inductively coupled plasma mass spectrometry (ICP MS), used as detector in chromatography and electrophoresis, and supported by electrospray and MALDI MS, appears as the linchpin analytical technique for these emerging areas. This review focuses on the recent advances in ICP MS in biological speciation analysis including sensitive detection of non-metals, especially of sulfur and phosphorus, couplings to capillary and nanoflow HPLC and capillary electrophoresis, laser ablation ICP MS detection of proteins in gel electrophoresis, and isotope dilution quantification of biomolecules. The paper can be considered as a followup of a previous review by the author on a similar topic (J. Szpunar, Analyst, 2000, 125, 963).

  14. Advances of vibrational spectroscopic methods in phytomics and bioanalysis.

    PubMed

    Huck, Christian W

    2014-01-01

    During the last couple of years great advances in vibrational spectroscopy including near-infrared (NIR), mid-infrared (MIR), attenuated total reflection (ATR) and imaging and also mapping techniques could be achieved. On the other hand spectral treatment features have improved dramatically allowing filtering out relevant information from spectral data much more efficiently and providing new insights into the biochemical composition. These advances offer new possible quality control strategies in phytomics and enable to get deeper insights into biochemical background in terms of medicinal relevant questions. It is the aim of the present article pointing out the technical and methodological advancements in the NIR and MIR field and to demonstrate the individual methods efficiency by discussing distinct selected applications.

  15. An advanced probabilistic structural analysis method for implicit performance functions

    NASA Technical Reports Server (NTRS)

    Wu, Y.-T.; Millwater, H. R.; Cruse, T. A.

    1989-01-01

    In probabilistic structural analysis, the performance or response functions usually are implicitly defined and must be solved by numerical analysis methods such as finite element methods. In such cases, the most commonly used probabilistic analysis tool is the mean-based, second-moment method which provides only the first two statistical moments. This paper presents a generalized advanced mean value (AMV) method which is capable of establishing the distributions to provide additional information for reliability design. The method requires slightly more computations than the second-moment method but is highly efficient relative to the other alternative methods. In particular, the examples show that the AMV method can be used to solve problems involving non-monotonic functions that result in truncated distributions.

  16. Application of quality by design to the development of analytical separation methods.

    PubMed

    Orlandini, Serena; Pinzauti, Sergio; Furlanetto, Sandra

    2013-01-01

    Recent pharmaceutical regulatory documents have stressed the critical importance of applying quality by design (QbD) principles for in-depth process understanding to ensure that product quality is built in by design. This article outlines the application of QbD concepts to the development of analytical separation methods, for example chromatography and capillary electrophoresis. QbD tools, for example risk assessment and design of experiments, enable enhanced quality to be integrated into the analytical method, enabling earlier understanding and identification of variables affecting method performance. A QbD guide is described, from identification of quality target product profile to definition of control strategy, emphasizing the main differences from the traditional quality by testing (QbT) approach. The different ways several authors have treated single QbD steps of method development are reviewed and compared. In a final section on outlook, attention is focused on general issues which have arisen from the surveyed literature, and on the need to change the researcher's mindset from the QbT to QbD approach as an important analytical trend for the near future.

  17. An analytical sensitivity method for use in integrated aeroservoelastic aircraft design

    NASA Technical Reports Server (NTRS)

    Gilbert, Michael G.

    1989-01-01

    Interdisciplinary analysis capabilities have been developed for aeroservoelastic aircraft and large flexible spacecraft, but the requisite integrated design methods are only beginning to be developed. One integrated design method which has received attention is based on hierarchal problem decompositions, optimization, and design sensitivity analyses. This paper highlights a design sensitivity analysis method for Linear Quadratic Gaussian (LQG) optimal control laws, enabling the use of LQG techniques in the hierarchal design methodology. The LQG sensitivity analysis method calculates the change in the optimal control law and resulting controlled system responses due to changes in fixed design integration parameters using analytical sensitivity equations. Numerical results of a LQG design sensitivity analysis for a realistic aeroservoelastic aircraft example are presented. In this example, the sensitivity of the optimal control law and aircraft response for various parameters such as wing bending natural frequency is determined. The sensitivity results computed from the analytical expressions are used to estimate changes in response resulting from changes in the parameters. Comparisons of the estimates with exact calculated responses show they are reasonably accurate for + or - 15 percent changes in the parameters. Evaluation of the analytical expressions is computationally faster than equivalent finite difference calculations.

  18. Comparison of five analytical methods for the determination of peroxide value in oxidized ghee.

    PubMed

    Mehta, Bhavbhuti M; Darji, V B; Aparnathi, K D

    2015-10-15

    In the present study, a comparison of five peroxide analytical methods was performed using oxidized ghee. The methods included the three iodometric titration viz. Bureau of Indian Standard (BIS), Association of Analytical Communities (AOAC) and American Oil Chemists' Society (AOCS), and two colorimetric methods, the ferrous xylenol orange (FOX) and ferric thiocyanate (International Dairy Federation, IDF) methods based on oxidation of iron. Six ghee samples were stored at 80 °C to accelerate deterioration and sampled periodically (every 48 h) for peroxides. Results were compared using the five methods for analysis as well as a flavor score (9 point hedonic scale). The correlation coefficients obtained using the different methods were in the order: FOX (-0.836) > IDF (-0.821) > AOCS (-0.798) > AOAC (-0.795) > BIS (-0.754). Thus, among the five methods used for determination of peroxide value of ghee during storage, the highest coefficient of correlation was obtained for the FOX method. The high correlations between the FOX and flavor data indicated that FOX was the most suitable method tested to determine peroxide value in oxidized ghee. PMID:25952892

  19. Advances in nucleic acid-based detection methods.

    PubMed Central

    Wolcott, M J

    1992-01-01

    Laboratory techniques based on nucleic acid methods have increased in popularity over the last decade with clinical microbiologists and other laboratory scientists who are concerned with the diagnosis of infectious agents. This increase in popularity is a result primarily of advances made in nucleic acid amplification and detection techniques. Polymerase chain reaction, the original nucleic acid amplification technique, changed the way many people viewed and used nucleic acid techniques in clinical settings. After the potential of polymerase chain reaction became apparent, other methods of nucleic acid amplification and detection were developed. These alternative nucleic acid amplification methods may become serious contenders for application to routine laboratory analyses. This review presents some background information on nucleic acid analyses that might be used in clinical and anatomical laboratories and describes some recent advances in the amplification and detection of nucleic acids. PMID:1423216

  20. Fracture Toughness in Advanced Monolithic Ceramics - SEPB Versus SEVENB Methods

    NASA Technical Reports Server (NTRS)

    Choi, S. R.; Gyekenyesi, J. P.

    2005-01-01

    Fracture toughness of a total of 13 advanced monolithic ceramics including silicon nitrides, silicon carbide, aluminas, and glass ceramic was determined at ambient temperature by using both single edge precracked beam (SEPB) and single edge v-notched beam (SEVNB) methods. Relatively good agreement in fracture toughness between the two methods was observed for advanced ceramics with flat R-curves; whereas, poor agreement in fracture toughness was seen for materials with rising R-curves. The discrepancy in fracture toughness between the two methods was due to stable crack growth with crack closure forces acting in the wake region of cracks even in SEVNB test specimens. The effect of discrepancy in fracture toughness was analyzed in terms of microstructural feature (grain size and shape), toughening exponent, and stable crack growth determined using back-face strain gaging.

  1. An analytical framework for determining life cycle cost implications of the advanced launch system

    NASA Astrophysics Data System (ADS)

    Stockman, William K.

    1988-12-01

    The product of this research effort was a simplified cost analysis tool that can be used to determine life cycle costs for the Advanced Launch System. The major objective was to develop a tool that would allow quick analysis of proposals and provide data input in a timely fashion. This effort produced a core program that can be used to determine life cycle costs as a function of system components, production infrastructures, reliability assumptions and flexible mission models. The life cycle cost model can operate in either a deterministic or stochastic mode depending on user inputs. An additional effort modeled the production infrastructure using a network flow system. This system modeled the flow of the basic vehicle components from initial production through final launch. The analysis tool uses a commercially available spreadsheet package available for most personal computers. The analyst using this program operates in a user-friendly environment that simplifies data input and problem formulation. The user has a wide variety of output formats and graphics options that simplify report generation.

  2. Environmental equity research: review with focus on outdoor air pollution research methods and analytic tools.

    PubMed

    Miao, Qun; Chen, Dongmei; Buzzelli, Michael; Aronson, Kristan J

    2015-01-01

    The objective of this study was to review environmental equity research on outdoor air pollution and, specifically, methods and tools used in research, published in English, with the aim of recommending the best methods and analytic tools. English language publications from 2000 to 2012 were identified in Google Scholar, Ovid MEDLINE, and PubMed. Research methodologies and results were reviewed and potential deficiencies and knowledge gaps identified. The publications show that exposure to outdoor air pollution differs by social factors, but findings are inconsistent in Canada. In terms of study designs, most were small and ecological and therefore prone to the ecological fallacy. Newer tools such as geographic information systems, modeling, and biomarkers offer improved precision in exposure measurement. Higher-quality research using large, individual-based samples and more precise analytic tools are needed to provide better evidence for policy-making to reduce environmental inequities.

  3. An analytical solution of temperature response in multilayered materials for transient methods

    SciTech Connect

    Araki, N.; Makino, A.; Ishiguro, T.; Mihara, J. )

    1992-05-01

    Transient methods, such as those with pulse- or stepwise heating, have often been used to measure thermal diffusivities of various materials including layered materials. The objective of the present study is to derive an analytical solution of the temperature rise in a multilayered material, the front surface of which is subjected to pulse- or stepwise heating. The Laplace transformation has been used to obtain the analytical solution. This solution will enable one to establish the appropriate measurement method for thermophysical properties of the multilayered material. It is also shown that the present solution can be extended to functionally gradient materials (FGM), in which thermophysical properties as well as compositions change continuously. 4 refs., 3 figs.

  4. Analytical approximate solution of the cooling problem by Adomian decomposition method

    NASA Astrophysics Data System (ADS)

    Alizadeh, Ebrahim; Sedighi, Kurosh; Farhadi, Mousa; Ebrahimi-Kebria, H. R.

    2009-02-01

    The Adomian decomposition method (ADM) can provide analytical approximation or approximated solution to a rather wide class of nonlinear (and stochastic) equations without linearization, perturbation, closure approximation, or discretization methods. In the present work, ADM is employed to solve the momentum and energy equations for laminar boundary layer flow over flat plate at zero incidences with neglecting the frictional heating. A trial and error strategy has been used to obtain the constant coefficient in the approximated solution. ADM provides an analytical solution in the form of an infinite power series. The effect of Adomian polynomial terms is considered and shows that the accuracy of results is increased with the increasing of Adomian polynomial terms. The velocity and thermal profiles on the boundary layer are calculated. Also the effect of the Prandtl number on the thermal boundary layer is obtained. Results show ADM can solve the nonlinear differential equations with negligible error compared to the exact solution.

  5. SRC-I demonstration plant analytical laboratory methods manual. Final technical report

    SciTech Connect

    Klusaritz, M.L.; Tewari, K.C.; Tiedge, W.F.; Skinner, R.W.; Znaimer, S.

    1983-03-01

    This manual is a compilation of analytical procedures required for operation of a Solvent-Refined Coal (SRC-I) demonstration or commercial plant. Each method reproduced in full includes a detailed procedure, a list of equipment and reagents, safety precautions, and, where possible, a precision statement. Procedures for the laboratory's environmental and industrial hygiene modules are not included. Required American Society for Testing and Materials (ASTM) methods are cited, and ICRC's suggested modifications to these methods for handling coal-derived products are provided.

  6. Analytic method for three-center nuclear attraction integrals: a generalization of the Gegenbauer addition theorem

    SciTech Connect

    Weatherford, C.A.

    1988-01-01

    A completely analytic method for evaluating three-center nuclear-attraction integrals for STOS is presented. The method exploits a separation of the STO into an evenly loaded solid harmonic and a OS STO. The harmonics are translated to the molecular center of mass in closed finite terms. The OS STO is translated using the Gegenbauer addition theorem; ls STOS are translated using a single parametric differentiation of the OS formula. Explicit formulas for the integrals are presented for arbitrarily located atoms. A numerical example is given to illustrate the method.

  7. Analytical solutions for determining residual stresses in two-dimensional domains using the contour method

    PubMed Central

    Kartal, Mehmet E.

    2013-01-01

    The contour method is one of the most prevalent destructive techniques for residual stress measurement. Up to now, the method has involved the use of the finite-element (FE) method to determine the residual stresses from the experimental measurements. This paper presents analytical solutions, obtained for a semi-infinite strip and a finite rectangle, which can be used to calculate the residual stresses directly from the measured data; thereby, eliminating the need for an FE approach. The technique is then used to determine the residual stresses in a variable-polarity plasma-arc welded plate and the results show good agreement with independent neutron diffraction measurements. PMID:24204187

  8. Analytical method for determining quantum well exciton properties in a magnetic field

    NASA Astrophysics Data System (ADS)

    Stépnicki, Piotr; Piétka, Barbara; Morier-Genoud, François; Deveaud, Benoît; Matuszewski, Michał

    2015-05-01

    We develop an analytical approximate method for determining the Bohr radii of Wannier-Mott excitons in thin quantum wells under the influence of magnetic field perpendicular to the quantum well plane. Our hybrid variational-perturbative method allows us to obtain simple closed formulas for exciton binding energies and optical transition rates. We confirm the reliability of our method through exciton-polariton experiments realized in a GaAs/AlAs microcavity with an 8 nm InxGa1 -xAs quantum well and magnetic field strengths as high as 14 T.

  9. A new validated analytical method for the quality control of red ginseng products

    PubMed Central

    Kim, Il-Woung; Cha, Kyu-Min; Wee, Jae Joon; Ye, Michael B.; Kim, Si-Kwan

    2013-01-01

    The main active components of Panax ginseng are ginsenosides. Ginsenoside Rb1 and Rg1 are accepted as marker substances for quality control worldwide. The analytical methods currently used to detect these two compounds unfairly penalize steamed and dried (red) P. ginseng preparations, because it has a lower content of those ginsenosides than white ginseng. To manufacture red ginseng products from fresh ginseng, the ginseng roots are exposed to high temperatures for many hours. This heating process converts the naturally occurring ginsenoside Rb1 and Rg1 into artifact ginsenosides such as ginsenoside Rg3, Rg5, Rh1, and Rh2, among others. This study highlights the absurdity of the current analytical practice by investigating the time-dependent changes in the crude saponin and the major natural and artifact ginsenosides contents during simmering. The results lead us to recommend (20S)- and (20R)-ginsenoside Rg3 as new reference materials to complement the current P. ginseng preparation reference materials ginsenoside Rb1 and Rg1. An attempt has also been made to establish validated qualitative and quantitative analytical procedures for these four compounds that meet International Conference of Harmonization (ICH) guidelines for specificity, linearity, range, accuracy, precision, detection limit, quantitation limit, robustness and system suitability. Based on these results, we suggest a validated analytical procedure which conforms to ICH guidelines and equally values the contents of ginsenosides in white and red ginseng preparations. PMID:24235862

  10. A new validated analytical method for the quality control of red ginseng products.

    PubMed

    Kim, Il-Woung; Cha, Kyu-Min; Wee, Jae Joon; Ye, Michael B; Kim, Si-Kwan

    2013-10-01

    The main active components of Panax ginseng are ginsenosides. Ginsenoside Rb1 and Rg1 are accepted as marker substances for quality control worldwide. The analytical methods currently used to detect these two compounds unfairly penalize steamed and dried (red) P. ginseng preparations, because it has a lower content of those ginsenosides than white ginseng. To manufacture red ginseng products from fresh ginseng, the ginseng roots are exposed to high temperatures for many hours. This heating process converts the naturally occurring ginsenoside Rb1 and Rg1 into artifact ginsenosides such as ginsenoside Rg3, Rg5, Rh1, and Rh2, among others. This study highlights the absurdity of the current analytical practice by investigating the time-dependent changes in the crude saponin and the major natural and artifact ginsenosides contents during simmering. The results lead us to recommend (20S)- and (20R)-ginsenoside Rg3 as new reference materials to complement the current P. ginseng preparation reference materials ginsenoside Rb1 and Rg1. An attempt has also been made to establish validated qualitative and quantitative analytical procedures for these four compounds that meet International Conference of Harmonization (ICH) guidelines for specificity, linearity, range, accuracy, precision, detection limit, quantitation limit, robustness and system suitability. Based on these results, we suggest a validated analytical procedure which conforms to ICH guidelines and equally values the contents of ginsenosides in white and red ginseng preparations.

  11. Method and apparatus for continuous fluid leak monitoring and detection in analytical instruments and instrument systems

    DOEpatents

    Weitz, Karl K.; Moore, Ronald J.

    2010-07-13

    A method and device are disclosed that provide for detection of fluid leaks in analytical instruments and instrument systems. The leak detection device includes a collection tube, a fluid absorbing material, and a circuit that electrically couples to an indicator device. When assembled, the leak detection device detects and monitors for fluid leaks, providing a preselected response in conjunction with the indicator device when contacted by a fluid.

  12. A comparative evaluation of analytical methods to allocate individual marks from a team mark

    NASA Astrophysics Data System (ADS)

    Nepal, Kali

    2012-08-01

    This study presents a comparative evaluation of analytical methods to allocate individual marks from a team mark. Only the methods that use or can be converted into some form of mathematical equations are analysed. Some of these methods focus primarily on the assessment of the quality of teamwork product (product assessment) while the others put greater emphasis on the assessment of teamwork performance (process assessment). The remaining methods try to strike a balance between product assessment and process assessment. To discuss the characteristics of these methods, graphical plots generated by the mathematical equations that collectively cover all possible team learning scenarios are discussed. Finally, a typical teamwork example is used to simplify the discussions. Although each of the methods discussed has its own merits for a particular application scenario, recent methods are relatively better in terms of a number of evaluation criteria.

  13. Determination of proline in honey: comparison between official methods, optimization and validation of the analytical methodology.

    PubMed

    Truzzi, Cristina; Annibaldi, Anna; Illuminati, Silvia; Finale, Carolina; Scarponi, Giuseppe

    2014-05-01

    The study compares official spectrophotometric methods for the determination of proline content in honey - those of the International Honey Commission (IHC) and the Association of Official Analytical Chemists (AOAC) - with the original Ough method. Results show that the extra time-consuming treatment stages added by the IHC method with respect to the Ough method are pointless. We demonstrate that the AOACs method proves to be the best in terms of accuracy and time saving. The optimized waiting time for the absorbance recording is set at 35min from the removal of reaction tubes from the boiling bath used in the sample treatment. The optimized method was validated in the matrix: linearity up to 1800mgL(-1), limit of detection 20mgL(-1), limit of quantification 61mgL(-1). The method was applied to 43 unifloral honey samples from the Marche region, Italy.

  14. Determination of proline in honey: comparison between official methods, optimization and validation of the analytical methodology.

    PubMed

    Truzzi, Cristina; Annibaldi, Anna; Illuminati, Silvia; Finale, Carolina; Scarponi, Giuseppe

    2014-05-01

    The study compares official spectrophotometric methods for the determination of proline content in honey - those of the International Honey Commission (IHC) and the Association of Official Analytical Chemists (AOAC) - with the original Ough method. Results show that the extra time-consuming treatment stages added by the IHC method with respect to the Ough method are pointless. We demonstrate that the AOACs method proves to be the best in terms of accuracy and time saving. The optimized waiting time for the absorbance recording is set at 35min from the removal of reaction tubes from the boiling bath used in the sample treatment. The optimized method was validated in the matrix: linearity up to 1800mgL(-1), limit of detection 20mgL(-1), limit of quantification 61mgL(-1). The method was applied to 43 unifloral honey samples from the Marche region, Italy. PMID:24360478

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

    NASA Astrophysics Data System (ADS)

    Hosen, Md. Alal; Chowdhury, M. S. H.; Ali, Mohammad Yeakub; Ismail, Ahmad Faris

    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.

  16. Instrumental characterization of odour: a combination of olfactory and analytical methods.

    PubMed

    Zarra, T; Naddeo, V; Belgiorno, V; Reiser, M; Kranert, M

    2009-01-01

    Odour emissions are a major environmental issue in wastewater treatment plants and are considered to be the main cause of disturbance noticed by the exposed population. Odour measurement is carried out using analytical or sensorial methods. Sensorial analysis, being assigned to the "human sensor", is the cause of a considerable uncertainty. In this study a correlation between analytical and sensorial methods was investigated. A novel tool was used to both define odour indexes and characterise the odour sources and the volatile substances that cause annoyance in a wastewater treatment plant, with the aim to remove the subjective component in the measure of the odours and define the induced impact. The sources and the main chemical substances responsible for the olfactory annoyances were identified. Around 36 different substances were detected, with more than half being smell relevant components as well as responsible. Dimethyl disulphide was identified as key compound. Results highlight the applicability of highly correlation between analytical and sensorial methods in odour emission monitoring.

  17. A New Splitting Method for Both Analytical and Preparative LC/MS

    NASA Astrophysics Data System (ADS)

    Cai, Yi; Adams, Daniel; Chen, Hao

    2013-11-01

    This paper presents a novel splitting method for liquid chromatography/mass spectrometry (LC/MS) application, which allows fast MS detection of LC-separated analytes and subsequent online analyte collection. In this approach, a PEEK capillary tube with a micro-orifice drilled on the tube side wall is used to connect with LC column. A small portion of LC eluent emerging from the orifice can be directly ionized by desorption electrospray ionization (DESI) with negligible time delay (6~10 ms) while the remaining analytes exiting the tube outlet can be collected. The DESI-MS analysis of eluted compounds shows narrow peaks and high sensitivity because of the extremely small dead volume of the orifice used for LC eluent splitting (as low as 4 nL) and the freedom to choose favorable DESI spray solvent. In addition, online derivatization using reactive DESI is possible for supercharging proteins and for enhancing their signals without introducing extra dead volume. Unlike UV detector used in traditional preparative LC experiments, this method is applicable to compounds without chromophores (e.g., saccharides) due to the use of MS detector. Furthermore, this splitting method well suits monolithic column-based ultra-fast LC separation at a high elution flow rate of 4 mL/min. [Figure not available: see fulltext.

  18. Analytical perturbation methods for studying a transversely isotropic medium in multipole acoustic logging

    NASA Astrophysics Data System (ADS)

    Zhang, Li; Liu, Xi-Feng; Yuan, Wen; Wang, Xiao-Tian

    2014-06-01

    A new analytical perturbation method is developed in this study to investigate the general reflection coefficients in the frequency-wavenumber domain of the acoustic field in a fluid-filled borehole surrounded by a transversely isotropic medium (TIM). The transversely isotropic medium with a symmetric axis parallel to the borehole axis, which is usually called a VTI medium, was adopted because its exact solutions exists, and a corresponding isotropic medium was adopted as a reference state of perturbation solution. The general reflection coefficients were originally calculated by using the perturbation method and were compared with the analytical solutions. The zero-, first- and second-order perturbation solutions for the general reflection coefficients excited by monopole, dipole and quadrupole sources were investigated for a transversely isotropic elastic solid. The results showed that the general reflection coefficients obtained by using the perturbation solutions and the analytical solutions were similar for all three sources. In summary, our study demonstrated that the perturbation method is valid and effective in acoustical logging. This work provided a theoretical foundation for extending perturbation analyses to complicated anisotropic acoustical logging applications.

  19. Advanced stress analysis methods applicable to turbine engine structures

    NASA Technical Reports Server (NTRS)

    Pian, Theodore H. H.

    1991-01-01

    The following tasks on the study of advanced stress analysis methods applicable to turbine engine structures are described: (1) constructions of special elements which contain traction-free circular boundaries; (2) formulation of new version of mixed variational principles and new version of hybrid stress elements; (3) establishment of methods for suppression of kinematic deformation modes; (4) construction of semiLoof plate and shell elements by assumed stress hybrid method; and (5) elastic-plastic analysis by viscoplasticity theory using the mechanical subelement model.

  20. Improved method of HIPOT testing of advanced ignition system product

    SciTech Connect

    Baker, P.C.

    1992-04-01

    A new method of high potential (HIPOT) testing of advanced ignition system (AIS) product was developed. The new incorporated using a silver-filled RTV silicone as the electrodes of the HIPOT tester instead of the preformed, semi-rigid aluminum electrodes of the current tester. Initial results indicate that the developed method was more sensitive to the testing requirements of the HIPOT test. A patent for the combination of the material used and the method of testing developed was attempted but was withdrawn following a patent search by the US Patent Office.

  1. Analytical methods of the U.S. Geological Survey's New York District Water-Analysis Laboratory

    USGS Publications Warehouse

    Lawrence, Gregory B.; Lincoln, Tricia A.; Horan-Ross, Debra A.; Olson, Mark L.; Waldron, Laura A.

    1995-01-01

    The New York District of the U.S. Geological Survey (USGS) in Troy, N.Y., operates a water-analysis laboratory for USGS watershed-research projects in the Northeast that require analyses of precipitation and of dilute surface water and soil water for major ions; it also provides analyses of certain chemical constituents in soils and soil gas samples. This report presents the methods for chemical analyses of water samples, soil-water samples, and soil-gas samples collected in wateshed-research projects. The introduction describes the general materials and technicques for eachmethod and explains the USGS quality-assurance program and data-management procedures; it also explains the use of cross reference to the three most commonly used methods manuals for analysis of dilute waters. The body of the report describes the analytical procedures for (1) solution analysis, (2) soil analysis, and (3) soil-gas analysis. The methods are presented in alphabetical order by constituent. The method for each constituent is preceded by (1) reference codes for pertinent sections of the three manuals mentioned above, (2) a list of the method's applications, and (3) a summary of the procedure. The methods section for each constitutent contains the following categories: instrumentation and equipment, sample preservation and storage, reagents and standards, analytical procedures, quality control, maintenance, interferences, safety considerations, and references. Sufficient information is presented for each method to allow the resulting data to be appropriately used in environmental samples.

  2. Pesticides in near-surface aquifers: An assessment using highly sensitive analytical methods and tritium

    SciTech Connect

    Kolpin, D.W.; Goolsby, D.A.; Thurman, E.M.

    1995-11-01

    In 1992, the U.S. Geological Survey (USGS) determined the distribution of pesticides in near-surface aquifers of the Midwestern USA to be much more widespread than originally determined during a 1991 USGS study. The frequency of pesticide detection increased from 28.4% during the 1991 study to 59.0% during the 1992 study. This increase in pesticide detection was primarily the result of a more sensitive analytical method that used reporting limits as much as 20 times lower than previously available and a threefold increase in the number of pesticide metabolites analyzed. No pesticide concentrations exceeded the U.S. Environmental Protection Agency`s (USEPAs) maximum contaminant levels or health advisory levels for drinking water. However, five of the six most frequently detected compounds during 1992 were pesticide metabolites that currently do not have drinking water standards determined. The frequent presence of pesticide metabolites for this study documents the importance of obtaining information on these compounds to understand the fate and transport of pesticides in the hydrologic system. It appears that the 56 parent compounds analyzed follow similar pathways through the hydrologic system as atrazine. When atrazine was detected by routine or sensitive analytical methods, there was an increased likelihood of detecting additional parent compounds. As expected, the frequency of pesticide detection was highly dependent on the analytical reporting limit. The number of atrazine detections more than doubled as the reporting limit decreased from 0.10 to 0.01 {mu}g/L. The 1992 data provided no indication that the frequency of pesticide detection would level off as improved analytical methods provide concentrations below 0.003 {mu}g/L. A relation was determined between groundwater age and the frequency of pesticide detection. 30 refs., 4 figs., 3 tabs.

  3. 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".

    PubMed

    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.

  4. Phonon dispersion on Ag (100) surface: A modified analytic embedded atom method study

    NASA Astrophysics Data System (ADS)

    Xiao-Jun, Zhang; Chang-Le, Chen

    2016-01-01

    Within the harmonic approximation, the analytic expression of the dynamical matrix is derived based on the modified analytic embedded atom method (MAEAM) and the dynamics theory of surface lattice. The surface phonon dispersions along three major symmetry directions , and X¯M¯ are calculated for the clean Ag (100) surface by using our derived formulas. We then discuss the polarization and localization of surface modes at points X¯ and M¯ by plotting the squared polarization vectors as a function of the layer index. The phonon frequencies of the surface modes calculated by MAEAM are compared with the available experimental and other theoretical data. It is found that the present results are generally in agreement with the referenced experimental or theoretical results, with a maximum deviation of 10.4%. The agreement shows that the modified analytic embedded atom method is a reasonable many-body potential model to quickly describe the surface lattice vibration. It also lays a significant foundation for studying the surface lattice vibration in other metals. Project supported by the National Natural Science Foundation of China (Grant Nos. 61471301 and 61078057), the Scientific Research Program Funded by Shaanxi Provincial Education Department, China (Grant No. 14JK1301), and the Specialized Research Fund for the Doctoral Program of Higher Education, China (Grant No. 20126102110045).

  5. An intercomparison study of analytical methods used for quantification of levoglucosan in ambient aerosol filter samples

    NASA Astrophysics Data System (ADS)

    Yttri, K. E.; Schnelle-Kreis, J.; Maenhaut, W.; Abbaszade, G.; Alves, C.; Bjerke, A.; Bonnier, N.; Bossi, R.; Claeys, M.; Dye, C.; Evtyugina, M.; García-Gacio, D.; Hillamo, R.; Hoffer, A.; Hyder, M.; Iinuma, Y.; Jaffrezo, J.-L.; Kasper-Giebl, A.; Kiss, G.; López-Mahia, P. L.; Pio, C.; Piot, C.; Ramirez-Santa-Cruz, C.; Sciare, J.; Teinilä, K.; Vermeylen, R.; Vicente, A.; Zimmermann, R.

    2015-01-01

    The monosaccharide anhydrides (MAs) levoglucosan, galactosan and mannosan are products of incomplete combustion and pyrolysis of cellulose and hemicelluloses, and are found to be major constituents of biomass burning (BB) aerosol particles. Hence, ambient aerosol particle concentrations of levoglucosan are commonly used to study the influence of residential wood burning, agricultural waste burning and wildfire emissions on ambient air quality. A European-wide intercomparison on the analysis of the three monosaccharide anhydrides was conducted based on ambient aerosol quartz fiber filter samples collected at a Norwegian urban background site during winter. Thus, the samples' content of MAs is representative for BB particles originating from residential wood burning. The purpose of the intercomparison was to examine the comparability of the great diversity of analytical methods used for analysis of levoglucosan, mannosan and galactosan in ambient aerosol filter samples. Thirteen laboratories participated, of which three applied high-performance anion-exchange chromatography (HPAEC), four used high-performance liquid chromatography (HPLC) or ultra-performance liquid chromatography (UPLC) and six resorted to gas chromatography (GC). The analytical methods used were of such diversity that they should be considered as thirteen different analytical methods. All of the thirteen laboratories reported levels of levoglucosan, whereas nine reported data for mannosan and/or galactosan. Eight of the thirteen laboratories reported levels for all three isomers. The accuracy for levoglucosan, presented as the mean percentage error (PE) for each participating laboratory, varied from -63 to 20%; however, for 62% of the laboratories the mean PE was within ±10%, and for 85% the mean PE was within ±20%. For mannosan, the corresponding range was -60 to 69%, but as for levoglucosan, the range was substantially smaller for a subselection of the laboratories; i.e. for 33% of the

  6. An intercomparison study of analytical methods used for quantification of levoglucosan in ambient aerosol filter samples

    NASA Astrophysics Data System (ADS)

    Yttri, K. E.; Schnelle-Kreiss, J.; Maenhaut, W.; Alves, C.; Bossi, R.; Bjerke, A.; Claeys, M.; Dye, C.; Evtyugina, M.; García-Gacio, D.; Gülcin, A.; Hillamo, R.; Hoffer, A.; Hyder, M.; Iinuma, Y.; Jaffrezo, J.-L.; Kasper-Giebl, A.; Kiss, G.; López-Mahia, P. L.; Pio, C.; Piot, C.; Ramirez-Santa-Cruz, C.; Sciare, J.; Teinilä, K.; Vermeylen, R.; Vicente, A.; Zimmermann, R.

    2014-07-01

    The monosaccharide anhydrides (MAs) levoglucosan, galactosan and mannosan are products of incomplete combustion and pyrolysis of cellulose and hemicelluloses, and are found to be major constituents of biomass burning aerosol particles. Hence, ambient aerosol particle concentrations of levoglucosan are commonly used to study the influence of residential wood burning, agricultural waste burning and wild fire emissions on ambient air quality. A European-wide intercomparison on the analysis of the three monosaccharide anhydrides was conducted based on ambient aerosol quartz fiber filter samples collected at a Norwegian urban background site during winter. Thus, the samples' content of MAs is representative for biomass burning particles originating from residential wood burning. The purpose of the intercomparison was to examine the comparability of the great diversity of analytical methods used for analysis of levoglucosan, mannosan and galactosan in ambient aerosol filter samples. Thirteen laboratories participated, of which three applied High-Performance Anion-Exchange Chromatography (HPAEC), four used High-Performance Liquid Chromatography (HPLC) or Ultra-Performance Liquid Chromatography (UPLC), and six resorted to Gas Chromatography (GC). The analytical methods used were of such diversity that they should be considered as thirteen different analytical methods. All of the thirteen laboratories reported levels of levoglucosan, whereas nine reported data for mannosan and/or galactosan. Eight of the thirteen laboratories reported levels for all three isomers. The accuracy for levoglucosan, presented as the mean percentage error (PE) for each participating laboratory, varied from -63 to 23%; however, for 62% of the laboratories the mean PE was within ±10%, and for 85% the mean PE was within ±20%. For mannosan, the corresponding range was -60 to 69%, but as for levoglucosan, the range was substantially smaller for a subselection of the laboratories; i.e., for 33% of

  7. Lead-210 in animal and human bone: A new analytical method

    SciTech Connect

    Fisenne, I.M. )

    1994-01-01

    Lead-210 delivers the highest radiation dose to the skeleton of any naturally occurring radionuclide. A robust analytical method for the accurate determination of its concentration in bone was developed which minimizes the use of hazardous chemicals. Dry-ashing experiments showed that no substantial loss of [sup 210]Pb occurred at [le]700[degrees]C. Additional experiments showed that no loss of [sup 222]Rn occurred from dry-ashed bone. Ashed human-bone samples from three US regional areas were analyzed for [sup 210]Pb and [sup 226]Ra using the new method. 9 refs., 3 figs., 1 tab.

  8. Interpolation method for accurate affinity ranking of arrayed ligand-analyte interactions.

    PubMed

    Schasfoort, Richard B M; Andree, Kiki C; van der Velde, Niels; van der Kooi, Alex; Stojanović, Ivan; Terstappen, Leon W M M

    2016-05-01

    The values of the affinity constants (kd, ka, and KD) that are determined by label-free interaction analysis methods are affected by the ligand density. This article outlines a surface plasmon resonance (SPR) imaging method that yields high-throughput globally fitted affinity ranking values using a 96-plex array. A kinetic titration experiment without a regeneration step has been applied for various coupled antibodies binding to a single antigen. Globally fitted rate (kd and ka) and dissociation equilibrium (KD) constants for various ligand densities and analyte concentrations are exponentially interpolated to the KD at Rmax = 100 RU response level (KD(R100)).

  9. Field sampling and selecting on-site analytical methods for explosives in soil

    SciTech Connect

    Crockett, A.B.; Craig, H.D.; Jenkins, T.F.; Sisk, W.E.

    1996-12-01

    A large number of defense-related sites are contaminated with elevated levels of secondary explosives. Levels of contamination range from barely detectable to levels above 10% that need special handling because of the detonation potential. Characterization of explosives-contaminated sites is particularly difficult because of the very heterogeneous distribution of contamination in the environment and within samples. To improve site characterization, several options exist including collecting more samples, providing on-site analytical data to help direct the investigation, compositing samples, improving homogenization of the samples, and extracting larger samples. This publication is intended to provide guidance to Remedial Project Managers regarding field sampling and on-site analytical methods for detecting and quantifying secondary explosive compounds in soils, and is not intended to include discussions of the safety issues associated with sites contaminated with explosive residues.

  10. Analytic second derivatives of the energy in the fragment molecular orbital method.

    PubMed

    Nakata, Hiroya; Nagata, Takeshi; Fedorov, Dmitri G; Yokojima, Satoshi; Kitaura, Kazuo; Nakamura, Shinichiro

    2013-04-28

    We developed the analytic second derivatives of the energy for the fragment molecular orbital (FMO) method. First we derived the analytic expressions and then introduced some approximations related to the first and second order coupled perturbed Hartree-Fock equations. We developed a parallel program for the FMO Hessian with approximations in GAMESS and used it to calculate infrared (IR) spectra and Gibbs free energies and to locate the transition states in SN2 reactions. The accuracy of the Hessian is demonstrated in comparison to ab initio results for polypeptides and a water cluster. By using the two residues per fragment division, we achieved the accuracy of 3 cm(-1) in the reduced mean square deviation of vibrational frequencies from ab initio for all three polyalanine isomers, while the zero point energy had the error not exceeding 0.3 kcal/mol. The role of the secondary structure on IR spectra, zero point energies, and Gibbs free energies is discussed.

  11. Analytic second derivatives of the energy in the fragment molecular orbital method

    NASA Astrophysics Data System (ADS)

    Nakata, Hiroya; Nagata, Takeshi; Fedorov, Dmitri G.; Yokojima, Satoshi; Kitaura, Kazuo; Nakamura, Shinichiro

    2013-04-01

    We developed the analytic second derivatives of the energy for the fragment molecular orbital (FMO) method. First we derived the analytic expressions and then introduced some approximations related to the first and second order coupled perturbed Hartree-Fock equations. We developed a parallel program for the FMO Hessian with approximations in GAMESS and used it to calculate infrared (IR) spectra and Gibbs free energies and to locate the transition states in SN2 reactions. The accuracy of the Hessian is demonstrated in comparison to ab initio results for polypeptides and a water cluster. By using the two residues per fragment division, we achieved the accuracy of 3 cm-1 in the reduced mean square deviation of vibrational frequencies from ab initio for all three polyalanine isomers, while the zero point energy had the error not exceeding 0.3 kcal/mol. The role of the secondary structure on IR spectra, zero point energies, and Gibbs free energies is discussed.

  12. Laboratory Techniques in Geology: Embedding Analytical Methods into the Undergraduate Curriculum

    NASA Astrophysics Data System (ADS)

    Baedke, S. J.; Johnson, E. A.; Kearns, L. E.; Mazza, S. E.; Gazel, E.

    2014-12-01

    Paid summer REU experiences successfully engage undergraduate students in research and encourage them to continue to graduate school and scientific careers. However these programs only accommodate a limited number of students due to funding constraints, faculty time commitments, and limited access to needed instrumentation. At JMU, the Department of Geology and Environmental Science has embedded undergraduate research into the curriculum. Each student fulfilling a BS in Geology or a BA in Earth Science completes 3 credits of research, including a 1-credit course on scientific communication, 2 credits of research or internship, followed by a presentation of that research. Our department has successfully acquired many analytical instruments and now has an XRD, SEM/EDS, FTIR, handheld Raman, AA, ion chromatograph, and an IRMS. To give as many students as possible an overview to the scientific uses and operation methods for these instruments, we revived a laboratory methods course that includes theory and practical use of instrumentation at JMU, plus XRF sample preparation and analysis training at Virginia Tech during a 1-day field trip. In addition to practical training, projects included analytical concepts such as evaluating analytical vs. natural uncertainty, determining error on multiple measurements, signal-to-noise ratio, and evaluating data quality. State funding through the 4-VA program helped pay for analytical supplies and support for students to complete research projects over the summer or during the next academic year using instrumentation from the course. This course exemplifies an alternative path to broadening participation in undergraduate research and creating stronger partnerships between PUI's and research universities.

  13. Advanced Analytical Techniques for the Measurement of Nanomaterials in Food and Agricultural Samples: A Review

    PubMed Central

    Bandyopadhyay, Susmita; Peralta-Videa, Jose R.; Gardea-Torresdey, Jorge L.

    2013-01-01

    Abstract Nanotechnology offers substantial prospects for the development of state-of-the-art products and applications for agriculture, water treatment, and food industry. Profuse use of nanoproducts will bring potential benefits to farmers, the food industry, and consumers, equally. However, after end-user applications, these products and residues will find their way into the environment. Therefore, discharged nanomaterials (NMs) need to be identified and quantified to determine their ecotoxicity and the levels of exposure. Detection and characterization of NMs and their residues in the environment, particularly in food and agricultural products, have been limited, as no single technique or method is suitable to identify and quantify NMs. In this review, we have discussed the available literature concerning detection, characterization, and measurement techniques for NMs in food and agricultural matrices, which include chromatography, flow field fractionation, electron microscopy, light scattering, and autofluorescence techniques, among others. PMID:23483065

  14. Review of analytical methods for the determination of pesticide residues in grapes.

    PubMed

    Grimalt, Susana; Dehouck, Pieter

    2016-02-12

    This review presents an overview of analytical methods for the analysis of pesticide residues in grapes and by-products in the last decade. The most widely used detection technique for the determination of pesticides in grapes is mass spectrometry combined with gas and/or liquid chromatography. In general, multi-residue methods with selective sample treatment methodologies have been developed for this purpose. However, this review focuses not only on these common multi-residue methods but also on specific methodologies as single-residue methods for the analysis of pesticides in grapes and by-products. Finally, the limitations of multi-residue methods, the future perspectives and the trends for pesticide residue analysis in grapes are reviewed.

  15. Allocation of Transaction Cost to Market Participants Using an Analytical Method in Deregulated Market

    NASA Astrophysics Data System (ADS)

    Jeyasankari, S.; Jeslin Drusila Nesamalar, J.; Charles Raja, S.; Venkatesh, P.

    2014-04-01

    Transmission cost allocation is one of the major challenges in transmission open access faced by the electric power sector. The purpose of this work is to provide an analytical method for allocating transmission transaction cost in deregulated market. This research work provides a usage based transaction cost allocation method based on line-flow impact factor (LIF) which relates the power flow in each line with respect to transacted power for the given transaction. This method provides the impact of line flows without running iterative power flow solution and is well suited for real time applications. The proposed method is compared with the Newton-Raphson (NR) method of cost allocation on sample six bus and practical Indian utility 69 bus systems by considering multilateral transaction.

  16. Argon thermochronology of mineral deposits; a review of analytical methods, formulations, and selected applications

    USGS Publications Warehouse

    Snee, Lawrence W.

    2002-01-01

    40Ar/39Ar geochronology is an experimentally robust and versatile method for constraining time and temperature in geologic processes. The argon method is the most broadly applied in mineral-deposit studies. Standard analytical methods and formulations exist, making the fundamentals of the method well defined. A variety of graphical representations exist for evaluating argon data. A broad range of minerals found in mineral deposits, alteration zones, and host rocks commonly is analyzed to provide age, temporal duration, and thermal conditions for mineralization events and processes. All are discussed in this report. The usefulness of and evolution of the applicability of the method are demonstrated in studies of the Panasqueira, Portugal, tin-tungsten deposit; the Cornubian batholith and associated mineral deposits, southwest England; the Red Mountain intrusive system and associated Urad-Henderson molybdenum deposits; and the Eastern Goldfields Province, Western Australia.

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

    PubMed

    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. PMID:19650633

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

    PubMed

    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.

  19. Advances in Statistical Methods for Substance Abuse Prevention Research

    PubMed Central

    MacKinnon, David P.; Lockwood, Chondra M.

    2010-01-01

    The paper describes advances in statistical methods for prevention research with a particular focus on substance abuse prevention. Standard analysis methods are extended to the typical research designs and characteristics of the data collected in prevention research. Prevention research often includes longitudinal measurement, clustering of data in units such as schools or clinics, missing data, and categorical as well as continuous outcome variables. Statistical methods to handle these features of prevention data are outlined. Developments in mediation, moderation, and implementation analysis allow for the extraction of more detailed information from a prevention study. Advancements in the interpretation of prevention research results include more widespread calculation of effect size and statistical power, the use of confidence intervals as well as hypothesis testing, detailed causal analysis of research findings, and meta-analysis. The increased availability of statistical software has contributed greatly to the use of new methods in prevention research. It is likely that the Internet will continue to stimulate the development and application of new methods. PMID:12940467

  20. Analytical method for space-fractional telegraph equation by homotopy perturbation transform method

    NASA Astrophysics Data System (ADS)

    Prakash, Amit

    2016-06-01

    The object of the present article is to study spacefractional telegraph equation by fractional Homotopy perturbation transform method (FHPTM). The homotopy perturbation transform method is an innovative adjustment in Laplace transform algorithm. Three test examples are presented to show the efficiency of the proposed technique.

  1. Analytical and experimental evaluation of joining silicon carbide to silicon carbide and silicon nitride to silicon nitride for advanced heat engine applications Phase 2. Final report

    SciTech Connect

    Sundberg, G.J.; Vartabedian, A.M.; Wade, J.A.; White, C.S.

    1994-10-01

    The purpose of joining, Phase 2 was to develop joining technologies for HIP`ed Si{sub 3}N{sub 4} with 4wt% Y{sub 2}O{sub 3} (NCX-5101) and for a siliconized SiC (NT230) for various geometries including: butt joins, curved joins and shaft to disk joins. In addition, more extensive mechanical characterization of silicon nitride joins to enhance the predictive capabilities of the analytical/numerical models for structural components in advanced heat engines was provided. Mechanical evaluation were performed by: flexure strength at 22 C and 1,370 C, stress rupture at 1,370 C, high temperature creep, 22 C tensile testing and spin tests. While the silicon nitride joins were produced with sufficient integrity for many applications, the lower join strength would limit its use in the more severe structural applications. Thus, the silicon carbide join quality was deemed unsatisfactory to advance to more complex, curved geometries. The silicon carbide joining methods covered within this contract, although not entirely successful, have emphasized the need to focus future efforts upon ways to obtain a homogeneous, well sintered parent/join interface prior to siliconization. In conclusion, the improved definition of the silicon carbide joining problem obtained by efforts during this contract have provided avenues for future work that could successfully obtain heat engine quality joins.

  2. Applications of flight control system methods to an advanced combat rotorcraft

    NASA Technical Reports Server (NTRS)

    Tischler, Mark B.; Fletcher, Jay W.; Morris, Patrick M.; Tucker, George T.

    1989-01-01

    Advanced flight control system design, analysis, and testing methodologies developed at the Ames Research Center are applied in an analytical and flight test evaluation of the Advanced Digital Optical Control System (ADOCS) demonstrator. The primary objectives are to describe the knowledge gained about the implications of digital flight control system design for rotorcraft, and to illustrate the analysis of the resulting handling-qualities in the context of the proposed new handling-qualities specification for rotorcraft. Topics covered in-depth are digital flight control design and analysis methods, flight testing techniques, ADOCS handling-qualities evaluation results, and correlation of flight test results with analytical models and the proposed handling-qualities specification. The evaluation of the ADOCS demonstrator indicates desirable response characteristics based on equivalent damping and frequency, but undersirably large effective time-delays (exceeding 240 m sec in all axes). Piloted handling-qualities are found to be desirable or adequate for all low, medium, and high pilot gain tasks; but handling-qualities are inadequate for ultra-high gain tasks such as slope and running landings.

  3. Changes in the Concentrations of Corticoid Metabolites--The Effect of Stress, Diet and Analytical Method.

    PubMed

    Dušková, Michaela; Sosvorová, Lucie; Vítků, Jana; Jandíková, Hana; Rácz, Beáta; Chlupáčová, Tereza; De Cordeiro, Jose; Stárka, Luboslav

    2015-01-01

    A precisely measured corticoid level is important for decision-making in daily clinical practice. These levels can be influenced in the pre-analytical phase, when the effect of stress, timing, and diet can be important. The aim of this study was to elucidate optimal conditions for blood sampling as well as the choice of analytical methods, which they will be used in measuring of corticoids. By studying ten women, we focused on the influences of the stress of cannulation and a large lunchtime meal on cortisol, cortisone, aldosterone and corticosterone levels. We further compared results of cortisol measurements from RIA and LC-MS/MS. Stress from cannulation caused increase of cortisol, cortisone and corticosterone already, when the cannula was being inserted. This indicates that this increase is stimulated by fear of the blood withdrawing rather, than just by the needle insertion itself. The effect of stress on corticosterone disappeared after an hour, while effect on other corticoids was still apparent. Concerning the lunchtime meal, we found an increase in all measured corticoids between 11 and 12 o'clock. After the food, there were marked decreases in cortisone and aldosterone, while declining levels of cortisol and corticosterone had rather plateaus. We compared cortisol in 90 plasma samples measured by a commercial RIA kit and the LC-MS/MS method. Results from both methods showed a strong correlation (r=0.85). When measuring corticoid metabolites, the chosen analytical method, eliminating stress factors, and precisely timed blood sampling considering the daily rhythm and food intake are critical.

  4. Changes in the Concentrations of Corticoid Metabolites--The Effect of Stress, Diet and Analytical Method.

    PubMed

    Dušková, Michaela; Sosvorová, Lucie; Vítků, Jana; Jandíková, Hana; Rácz, Beáta; Chlupáčová, Tereza; De Cordeiro, Jose; Stárka, Luboslav

    2015-01-01

    A precisely measured corticoid level is important for decision-making in daily clinical practice. These levels can be influenced in the pre-analytical phase, when the effect of stress, timing, and diet can be important. The aim of this study was to elucidate optimal conditions for blood sampling as well as the choice of analytical methods, which they will be used in measuring of corticoids. By studying ten women, we focused on the influences of the stress of cannulation and a large lunchtime meal on cortisol, cortisone, aldosterone and corticosterone levels. We further compared results of cortisol measurements from RIA and LC-MS/MS. Stress from cannulation caused increase of cortisol, cortisone and corticosterone already, when the cannula was being inserted. This indicates that this increase is stimulated by fear of the blood withdrawing rather, than just by the needle insertion itself. The effect of stress on corticosterone disappeared after an hour, while effect on other corticoids was still apparent. Concerning the lunchtime meal, we found an increase in all measured corticoids between 11 and 12 o'clock. After the food, there were marked decreases in cortisone and aldosterone, while declining levels of cortisol and corticosterone had rather plateaus. We compared cortisol in 90 plasma samples measured by a commercial RIA kit and the LC-MS/MS method. Results from both methods showed a strong correlation (r=0.85). When measuring corticoid metabolites, the chosen analytical method, eliminating stress factors, and precisely timed blood sampling considering the daily rhythm and food intake are critical. PMID:26654800

  5. Comparison of the acetyl bromide spectrophotometric method with other analytical lignin methods for determining lignin concentration in forage samples.

    PubMed

    Fukushima, Romualdo S; Hatfield, Ronald D

    2004-06-16

    Present analytical methods to quantify lignin in herbaceous plants are not totally satisfactory. A spectrophotometric method, acetyl bromide soluble lignin (ABSL), has been employed to determine lignin concentration in a range of plant materials. In this work, lignin extracted with acidic dioxane was used to develop standard curves and to calculate the derived linear regression equation (slope equals absorptivity value or extinction coefficient) for determining the lignin concentration of respective cell wall samples. This procedure yielded lignin values that were different from those obtained with Klason lignin, acid detergent acid insoluble lignin, or permanganate lignin procedures. Correlations with in vitro dry matter or cell wall digestibility of samples were highest with data from the spectrophotometric technique. The ABSL method employing as standard lignin extracted with acidic dioxane has the potential to be employed as an analytical method to determine lignin concentration in a range of forage materials. It may be useful in developing a quick and easy method to predict in vitro digestibility on the basis of the total lignin content of a sample.

  6. Adaptive correction method for an OCXO and investigation of analytical cumulative time error upper bound.

    PubMed

    Zhou, Hui; Kunz, Thomas; Schwartz, Howard

    2011-01-01

    Traditional oscillators used in timing modules of CDMA and WiMAX base stations are large and expensive. Applying cheaper and smaller, albeit more inaccurate, oscillators in timing modules is an interesting research challenge. An adaptive control algorithm is presented to enhance the oscillators to meet the requirements of base stations during holdover mode. An oscillator frequency stability model is developed for the adaptive control algorithm. This model takes into account the control loop which creates the correction signal when the timing module is in locked mode. A recursive prediction error method is used to identify the system model parameters. Simulation results show that an oscillator enhanced by our adaptive control algorithm improves the oscillator performance significantly, compared with uncorrected oscillators. Our results also show the benefit of explicitly modeling the control loop. Finally, the cumulative time error upper bound of such enhanced oscillators is investigated analytically and comparison results between the analytical and simulated upper bound are provided. The results show that the analytical upper bound can serve as a practical guide for system designers. PMID:21244973

  7. Adaptive correction method for an OCXO and investigation of analytical cumulative time error upper bound.

    PubMed

    Zhou, Hui; Kunz, Thomas; Schwartz, Howard

    2011-01-01

    Traditional oscillators used in timing modules of CDMA and WiMAX base stations are large and expensive. Applying cheaper and smaller, albeit more inaccurate, oscillators in timing modules is an interesting research challenge. An adaptive control algorithm is presented to enhance the oscillators to meet the requirements of base stations during holdover mode. An oscillator frequency stability model is developed for the adaptive control algorithm. This model takes into account the control loop which creates the correction signal when the timing module is in locked mode. A recursive prediction error method is used to identify the system model parameters. Simulation results show that an oscillator enhanced by our adaptive control algorithm improves the oscillator performance significantly, compared with uncorrected oscillators. Our results also show the benefit of explicitly modeling the control loop. Finally, the cumulative time error upper bound of such enhanced oscillators is investigated analytically and comparison results between the analytical and simulated upper bound are provided. The results show that the analytical upper bound can serve as a practical guide for system designers.

  8. Analytical sensitivity analysis of transient groundwater flow in a bounded model domain using the adjoint method

    NASA Astrophysics Data System (ADS)

    Lu, Zhiming; Vesselinov, Velimir V.

    2015-07-01

    Sensitivity analyses are an important component of any modeling exercise. We have developed an analytical methodology based on the adjoint method to compute sensitivities of a state variable (hydraulic head) to model parameters (hydraulic conductivity and storage coefficient) for transient groundwater flow in a confined and randomly heterogeneous aquifer under ambient and pumping conditions. For a special case of two-dimensional rectangular domains, these sensitivities are represented in terms of the problem configuration (the domain size, boundary configuration, medium properties, pumping schedules and rates, and observation locations and times), and there is no need to actually solve the adjoint equations. As an example, we present analyses of the obtained solution for typical groundwater flow conditions. Analytical solutions allow us to calculate sensitivities efficiently, which can be useful for model-based analyses such as parameter estimation, data-worth evaluation, and optimal experimental design related to sampling frequency and locations of observation wells. The analytical approach is not limited to groundwater applications but can be extended to any other mathematical problem with similar governing equations and under similar conceptual conditions.

  9. A nearly analytic symplectically partitioned Runge-Kutta method for 2-D seismic wave equations

    NASA Astrophysics Data System (ADS)

    Ma, Xiao; Yang, Dinghui; Liu, Faqi

    2011-10-01

    In this paper, we develop a new nearly analytic symplectically partitioned Runge-Kutta (NSPRK) method for numerically solving elastic wave equations. In this method, we first transform the elastic wave equations into a Hamiltonian system, and use the nearly analytic discrete operator to approximate the high-order spatial differential operators, and then we employ the partitioned second-order symplectic Runge-Kutta method to numerically solve the resulted semi-discrete Hamiltonian ordinary differential equations (ODEs). We investigate in great detail on the properties of the NSPRK method that includes the stability condition for the P-SV wave in a 2-D homogeneous isotropic medium, the computational efficiency, and the numerical dispersion relation for the 2-D acoustic case. Meanwhile, we apply the NSPRK to simulate the elastic wave propagating in several multilayer models with both strong velocity contrasts and fluctuating interfaces. Both theoretical analysis and numerical results show that the NSPRK can effectively suppress the numerical dispersion resulted from the discretization of the wave equations, and more importantly, it preserves the symplecticity structure for long-time computation. In addition, numerical experiments demonstrate that the NSPRK is effective to combine the split perfectly matched layer boundary conditions to take care of the reflections from the artificial boundaries.

  10. Approximate analytic method for high-apogee twelve-hour orbits of artificial Earth's satellites

    NASA Astrophysics Data System (ADS)

    Vashkovyaka, M. A.; Zaslavskii, G. S.

    2016-09-01

    We propose an approach to the study of the evolution of high-apogee twelve-hour orbits of artificial Earth's satellites. We describe parameters of the motion model used for the artificial Earth's satellite such that the principal gravitational perturbations of the Moon and Sun, nonsphericity of the Earth, and perturbations from the light pressure force are approximately taken into account. To solve the system of averaged equations describing the evolution of the orbit parameters of an artificial satellite, we use both numeric and analytic methods. To select initial parameters of the twelve-hour orbit, we assume that the path of the satellite along the surface of the Earth is stable. Results obtained by the analytic method and by the numerical integration of the evolving system are compared. For intervals of several years, we obtain estimates of oscillation periods and amplitudes for orbital elements. To verify the results and estimate the precision of the method, we use the numerical integration of rigorous (not averaged) equations of motion of the artificial satellite: they take into account forces acting on the satellite substantially more completely and precisely. The described method can be applied not only to the investigation of orbit evolutions of artificial satellites of the Earth; it can be applied to the investigation of the orbit evolution for other planets of the Solar system provided that the corresponding research problem will arise in the future and the considered special class of resonance orbits of satellites will be used for that purpose.

  11. An analytical method for measuring α-amylase activity in starch-containing foods.

    PubMed

    Koyama, Kazuo; Hirao, Takashi; Toriba, Akira; Hayakawa, Kazuichi

    2013-05-01

    The quality of starch-containing foods may be significantly impaired by contamination with very small amounts of α-amylase, which can enzymatically hydrolyze the starch and cause viscosity loss. Thus, for quality control, it is necessary to have an analytical method that can measure low amylase activity. We developed a sensitive analytical method for measuring the activity of α-amylase (from Bacillus subtilis) in starch-containing foods. The method consists of six steps: (1) crude extraction of α-amylase by centrifugation and filtration; (2) α-amylase purification by desalting and anion-exchange chromatography; (3) reaction of the purified amylase with boron-dipyrromethene (BODIPY)-labeled substrate, which releases a fluorescent fragment upon digestion of the substrate, thus avoiding interference from starch derivatives in the sample; (4) stopping the reaction with acetonitrile; (5) reversed-phase solid-phase extraction of the fluorescent substrate to remove contaminating dye and impurities; and (6) separation and measurement of BODIPY fluorescence by HPLC. The proposed method could quantify α-amylase activities as low as 10 mU/mL, which is enough to reduce the viscosity of starch-containing foods.

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

    SciTech Connect

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

    1994-09-30

    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.

  13. Analytical and Biological Methods for Probing the Blood-Brain Barrier

    NASA Astrophysics Data System (ADS)

    Kuhnline, Sloan; Courtney, D.; Nandi, Pradyot; Linz, Thomas H.; Aldrich, Jane V.; Audus, Kenneth L.; Lunte, Susan M.

    2012-07-01

    The blood-brain barrier (BBB) is an important interface between the peripheral and central nervous systems. It protects the brain against the infiltration of harmful substances and regulates the permeation of beneficial endogenous substances from the blood into the extracellular fluid of the brain. It can also present a major obstacle in the development of drugs that are targeted for the central nervous system. Several methods have been developed to investigate the transport and metabolism of drugs, peptides, and endogenous compounds at the BBB. In vivo methods include intravenous injection, brain perfusion, positron emission tomography, and microdialysis sampling. Researchers have also developed in vitro cell-culture models that can be employed to investigate transport and metabolism at the BBB without the complication of systemic involvement. All these methods require sensitive and selective analytical methods to monitor the transport and metabolism of the compounds of interest at the BBB.

  14. Analytical and Biological Methods for Probing the Blood-Brain Barrier

    PubMed Central

    Sloan, Courtney D. Kuhnline; Nandi, Pradyot; Linz, Thomas H.; Aldrich, Jane V.; Audus, Kenneth L.; Lunte, Susan M.

    2013-01-01

    The blood-brain barrier (BBB) is an important interface between the peripheral and central nervous systems. It protects the brain against the infiltration of harmful substances and regulates the permeation of beneficial endogenous substances from the blood into the extracellular fluid of the brain. It can also present a major obstacle in the development of drugs that are targeted for the central nervous system. Several methods have been developed to investigate the transport and metabolism of drugs, peptides, and endogenous compounds at the BBB. In vivo methods include intravenous injection, brain perfusion, positron emission tomography, and microdialysis sampling. Researchers have also developed in vitro cell-culture models that can be employed to investigate transport and metabolism at the BBB without the complication of systemic involvement. All these methods require sensitive and selective analytical methods to monitor the transport and metabolism of the compounds of interest at the BBB. PMID:22708905

  15. Dynamical analysis of the avian-human influenza epidemic model using the semi-analytical method

    NASA Astrophysics Data System (ADS)

    Jabbari, Azizeh; Kheiri, Hossein; Bekir, Ahmet

    2015-03-01

    In this work, we present a dynamic behavior of the avian-human influenza epidemic model by using efficient computational algorithm, namely the multistage differential transform method(MsDTM). The MsDTM is used here as an algorithm for approximating the solutions of the avian-human influenza epidemic model in a sequence of time intervals. In order to show the efficiency of the method, the obtained numerical results are compared with the fourth-order Runge-Kutta method (RK4M) and differential transform method(DTM) solutions. It is shown that the MsDTM has the advantage of giving an analytical form of the solution within each time interval which is not possible in purely numerical techniques like RK4M.

  16. The dynamics of a cantilevered pipe aspirating fluid studied by experimental, numerical and analytical methods

    NASA Astrophysics Data System (ADS)

    Giacobbi, Dana B.; Rinaldi, Stephanie; Semler, Christian; Païdoussis, Michael P.

    2012-04-01

    This paper investigates the dynamics of a slender, flexible, aspirating cantilevered pipe, ingesting fluid at its free end and conveying it towards its clamped end. The problem is interesting not only from a fundamental perspective, but also because applications exist, notably in ocean mining. First, the need for the present work is demonstrated through a review of previous research into the topic - spanning many years and yielding often contradictory results - most recently suggesting that the system loses stability by flutter at relatively low flow velocities. In the present paper, that conclusion is refined and expanded upon by exploring the problem in three ways: experimentally, numerically and analytically. First, air-flow experiments were conducted using different elastomer pipes and intake shapes, in which the flow velocity of the fluid was varied and the frequency and amplitude of oscillation of the pipe were measured. Second, a fully coupled Computational Fluid Dynamics (CFD) and Computational Structural Mechanics (CSM) model was developed in ANSYS™ in order to simulate experiments and corroborate experimental results. Finally, using a Newtonian analytical approach, a new linear equation of motion describing the system was derived, and then solved via the Galerkin method in order to determine its stability characteristics. Heavily influenced by the CFD analysis, the proposed analytical model is different from previous ones, most notably because of the inclusion of a two-part fluid depressurisation at the intake. In general, both the actual and numerical experiments suggest a first-mode loss of stability by flutter at flow velocities comparable to those for the discharging case, which agrees with the results from the new analytical model.

  17. Method for detection and reconstruction of gravitational wave transients with networks of advanced detectors

    NASA Astrophysics Data System (ADS)

    Klimenko, S.; Vedovato, G.; Drago, M.; Salemi, F.; Tiwari, V.; Prodi, G. A.; Lazzaro, C.; Ackley, K.; Tiwari, S.; Da Silva, C. F.; Mitselmakher, G.

    2016-02-01

    We present a method for detection and reconstruction of the gravitational wave (GW) transients with the networks of advanced detectors. Originally designed to search for transients with the initial GW detectors, it uses significantly improved algorithms, which enhance both the low-latency searches with rapid localization of GW events for the electromagnetic follow-up and high confidence detection of a broad range of the transient GW sources. In this paper, we present the analytic framework of the method. Following a short description of the core analysis algorithms, we introduce a novel approach to the reconstruction of the GW polarization from a pattern of detector responses to a GW signal. This polarization pattern is a unique signature of an arbitrary GW signal that can be measured independently from the other source parameters. The polarization measurements enable rapid reconstruction of the GW waveforms, sky localization, and helps identification of the source origin.

  18. The riddle of Siegfried: exploring methods and psychological perspectives in analytical psychology.

    PubMed

    Barreto, Marco Heleno

    2016-02-01

    Jung's dream of the killing of Siegfried poses a riddle: why did the unconscious choose precisely Siegfried as the hero to be murdered? Jung himself declares that he does not know. This paper attempts to decipher this riddle using three distinct methodological approaches accepted by Jung, two of them in fact grounded in his theories of dream interpretation. Besides presenting some possible answers to the riddle of Siegfried, this interpretative reflection brings to light the discrepancy of the psychological perspectives created by the heterogeneity of methods within analytical psychology.

  19. The riddle of Siegfried: exploring methods and psychological perspectives in analytical psychology.

    PubMed

    Barreto, Marco Heleno

    2016-02-01

    Jung's dream of the killing of Siegfried poses a riddle: why did the unconscious choose precisely Siegfried as the hero to be murdered? Jung himself declares that he does not know. This paper attempts to decipher this riddle using three distinct methodological approaches accepted by Jung, two of them in fact grounded in his theories of dream interpretation. Besides presenting some possible answers to the riddle of Siegfried, this interpretative reflection brings to light the discrepancy of the psychological perspectives created by the heterogeneity of methods within analytical psychology. PMID:26785416

  20. Research progress of pharmacological activities and analytical methods for plant origin proteins.

    PubMed

    Li, Chun-hong; Chen, Cen; Xia, Zhi-ning; Yang, Feng-qing

    2015-07-01

    As one of the important active components of traditional Chinese medicine (TCM), plant origin active proteins have many significant pharmacological functions. According to researches on the plant origin active proteins reported in recent years, pharmacological effects include anti-tumor, immune regulation, anti-oxidant, anti-pathogeny microorganism, anti-thrombus, as well as hypolipidemic and hypoglycemic activities of plant origin were reviewed, respectively. On the other hand, the analytical methods including chromatography, spectroscopy, electrophoresis and mass spectrometry for plant origin proteins analysis were also summarized. The main purpose of this paper is providing a reference for future development and application of plant active proteins.