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Sample records for fluorescence complementation analysis

  1. Complementing Gender Analysis Methods.

    Kumar, Anant

    2016-01-01

    The existing gender analysis frameworks start with a premise that men and women are equal and should be treated equally. These frameworks give emphasis on equal distribution of resources between men and women and believe that this will bring equality which is not always true. Despite equal distribution of resources, women tend to suffer and experience discrimination in many areas of their lives such as the power to control resources within social relationships, and the need for emotional security and reproductive rights within interpersonal relationships. These frameworks believe that patriarchy as an institution plays an important role in women's oppression, exploitation, and it is a barrier in their empowerment and rights. Thus, some think that by ensuring equal distribution of resources and empowering women economically, institutions like patriarchy can be challenged. These frameworks are based on proposed equality principle which puts men and women in competing roles. Thus, the real equality will never be achieved. Contrary to the existing gender analysis frameworks, the Complementing Gender Analysis framework proposed by the author provides a new approach toward gender analysis which not only recognizes the role of economic empowerment and equal distribution of resources but suggests to incorporate the concept and role of social capital, equity, and doing gender in gender analysis which is based on perceived equity principle, putting men and women in complementing roles that may lead to equality. In this article the author reviews the mainstream gender theories in development from the viewpoint of the complementary roles of gender. This alternative view is argued based on existing literature and an anecdote of observations made by the author. While criticizing the equality theory, the author offers equity theory in resolving the gender conflict by using the concept of social and psychological capital.

  2. Construction of a bimolecular fluorescence complementation (BiFC ...

    Protein–protein interactions are essential for signal transduction in cells. Bimolecular fluorescence complementation (BiFC) is a novel technology that utilises green fluorescent proteins to visualize protein–protein interactions and subcellular protein localisation. BiFC based on pSATN vectors are a good system for ...

  3. Construction of a bimolecular fluorescence complementation (BiFC ...

    DR. NJ TONUKARI

    2012-08-02

    Aug 2, 2012 ... Accepted 8 June, 2012. Protein–protein interactions are essential for signal transduction in cells. ... BiFC is a novel technology that is used for identifying .... occasional fluorescence was observed, it was very weak ... Light field.

  4. Complementation analysis of ataxia-telangiectasia

    Jaspers, N.G.; Painter, R.B.; Paterson, M.C.; Kidson, C.; Inoue, T.

    1985-01-01

    In a number of laboratories genetic analysis of ataxia-telangiectasia (AT) has been performed by studying the expression of the AT phenotype in fused somatic cells or mixtures of cell-free extracts from different patients. Complementation of the defective response to ionizing radiation was observed frequently, considering four different parameters for radiosensitivity in AT. The combined results from studies on cultured fibroblasts or lymphoblastoid cells from 17 unrelated families revealed the presence of at least four and possibly nine complementation groups. These findings suggest that there is an extensive genetic heterogeneity in AT. More extensive studies are needed for an integration of these data and to provide a set of genetically characterized cell strains for future research of the AT genetic defect

  5. Limestone rocks analysis by X-ray fluorescence analysis

    Izquierdo M, G.; Ponce R, R.; Vazquez J, J.

    1996-01-01

    By request of a private company, employing basically X-ray fluorescence analysis (X RF), was established a fast and accurate method for the analysis of the major elements in limestone rocks. Additionally, for complementing analysis was determined by ion chromatography, the chlorides appearance and by atomic absorption of sodium. By gravimetry, was determined the losses by ignition and the alpha quartz. (Author)

  6. Genome-Wide Bimolecular Fluorescence Complementation-Based Proteomic Analysis of Toxoplasma gondii ROP18’s Human Interactome Shows Its Key Role in Regulation of Cell Immunity and Apoptosis

    Jing Xia

    2018-02-01

    Full Text Available Toxoplasma gondii rhoptry protein ROP18 (TgROP18 is a key virulence factor secreted into the host cell during invasion, where it modulates the host cell response by interacting with its host targets. However, only a few TgROP18 targets have been identified. In this study, we applied a high-throughput protein–protein interaction (PPI screening in human cells using bimolecular fluorescence complementation (BiFC to identify the targets of Type I strain ROP18 (ROP18I and Type II strain ROP18 (ROP18II. From a pool of more than 18,000 human proteins, 492 and 141 proteins were identified as the targets of ROP18I and ROP18II, respectively. Gene ontology, search tool for the retrieval of interacting genes/proteins PPI network, and Ingenuity pathway analyses revealed that the majority of these proteins were associated with immune response and apoptosis. This indicates a key role of TgROP18 in manipulating host’s immunity and cell apoptosis, which might contribute to the immune escape and successful parasitism of the parasite. Among the proteins identified, the immunity-related proteins N-myc and STAT interactor, IL20RB, IL21, ubiquitin C, and vimentin and the apoptosis-related protein P2RX1 were further verified as ROP18I targets by sensitized emission-fluorescence resonance energy transfer (SE-FRET and co-immunoprecipitation. Our study substantially contributes to the current limited knowledge on human targets of TgROP18 and provides a novel tool to investigate the function of parasite effectors in human cells.

  7. Image reconstruction of fluorescent molecular tomography based on the tree structured Schur complement decomposition

    Wang Jiajun

    2010-05-01

    Full Text Available Abstract Background The inverse problem of fluorescent molecular tomography (FMT often involves complex large-scale matrix operations, which may lead to unacceptable computational errors and complexity. In this research, a tree structured Schur complement decomposition strategy is proposed to accelerate the reconstruction process and reduce the computational complexity. Additionally, an adaptive regularization scheme is developed to improve the ill-posedness of the inverse problem. Methods The global system is decomposed level by level with the Schur complement system along two paths in the tree structure. The resultant subsystems are solved in combination with the biconjugate gradient method. The mesh for the inverse problem is generated incorporating the prior information. During the reconstruction, the regularization parameters are adaptive not only to the spatial variations but also to the variations of the objective function to tackle the ill-posed nature of the inverse problem. Results Simulation results demonstrate that the strategy of the tree structured Schur complement decomposition obviously outperforms the previous methods, such as the conventional Conjugate-Gradient (CG and the Schur CG methods, in both reconstruction accuracy and speed. As compared with the Tikhonov regularization method, the adaptive regularization scheme can significantly improve ill-posedness of the inverse problem. Conclusions The methods proposed in this paper can significantly improve the reconstructed image quality of FMT and accelerate the reconstruction process.

  8. Implementing quantitative analysis and its complement

    Rasmuson, D.M.; Nelson, W.R.; Shepherd, J.C.

    1982-01-01

    This paper presents an application of risk analysis for the evaluation of nuclear reactor facility operation. Common cause failure analysis (CCFA) techniques to identify potential problem areas are discussed. Integration of CCFA and response trees, a particular form of the path sets of a success tree, to gain significant insight into the operation of the facility is also demonstrated. An example illustrating the development of the risk analysis methodology, development of the fault trees, generation of response trees, and evaluation of the CCFA is presented to explain the technique

  9. Bimolecular Fluorescence Complementation of Alpha-synuclein Demonstrates its Oligomerization with Dopaminergic Phenotype in Mice

    Waijiao Cai

    2018-03-01

    Full Text Available Alpha-synuclein (αSyn is encoded by the first causal gene identified in Parkinson's disease (PD and is the main component of Lewy bodies, a pathological hallmark of PD. aSyn-based animal models have contributed to our understanding of PD pathophysiology and to the development of therapeutics. Overexpression of human wildtype αSyn by viral vectors in rodents recapitulates the loss of dopaminergic neurons from the substantia nigra, another defining pathological feature of the disease. The development of a rat model exhibiting bimolecular fluorescence complementation (BiFC of αSyn by recombinant adeno-associated virus facilitates detection of the toxic αSyn oligomers species. We report here neurochemical, neuropathological and behavioral characterization of BiFC of αSyn in mice. Overexpression and oligomerization of αSyn through BiFC is detected by conjugated fluorescence. Reduced striatal dopamine and loss of nigral dopaminergic neurons are accompanied neuroinflammation and abnormal motor activities. Our mouse model may provide a valuable tool to study the role of αSyn in PD and to explore therapeutic approaches. Keywords: Parkinson's disease, Alpha-synuclein, Mouse model, Oligomers, Neuroinflammation

  10. Interactions among the early Escherichia coli divisome proteins revealed by bimolecular fluorescence complementation.

    Pazos, Manuel; Natale, Paolo; Margolin, William; Vicente, Miguel

    2013-12-01

    We used bimolecular fluorescence complementation (BiFC) assays to detect protein-protein interactions of all possible pairs of the essential Escherichia coli proto-ring components, FtsZ, FtsA and ZipA, as well as the non-essential FtsZ-associated proteins ZapA and ZapB. We found an unexpected interaction between ZipA and ZapB at potential cell division sites, and when co-overproduced, they induced long narrow constrictions at division sites that were dependent on FtsZ. These assays also uncovered an interaction between ZipA and ZapA that was mediated by FtsZ. BiFC with ZapA and ZapB showed that in addition to their expected interaction at midcell, they also interact at the cell poles. BiFC detected interaction between FtsZ and ZapB at midcell and close to the poles. Results from the remaining pairwise combinations confirmed known interactions between FtsZ and ZipA, and ZapB with itself. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  11. Visualizing double-stranded RNA distribution and dynamics in living cells by dsRNA binding-dependent fluorescence complementation

    Cheng, Xiaofei; Deng, Ping; Cui, Hongguang; Wang, Aiming

    2015-01-01

    Double-stranded RNA (dsRNA) is an important type of RNA that plays essential roles in diverse cellular processes in eukaryotic organisms and a hallmark in infections by positive-sense RNA viruses. Currently, no in vivo technology has been developed for visualizing dsRNA in living cells. Here, we report a dsRNA binding-dependent fluorescence complementation (dRBFC) assay that can be used to efficiently monitor dsRNA distribution and dynamics in vivo. The system consists of two dsRNA-binding proteins, which are fused to the N- and C-terminal halves of the yellow fluorescent protein (YFP). Binding of the two fusion proteins to a common dsRNA brings the split YFP halves in close proximity, leading to the reconstitution of the fluorescence-competent structure and restoration of fluorescence. Using this technique, we were able to visualize the distribution and trafficking of the replicative RNA intermediates of positive-sense RNA viruses in living cells. - Highlights: • A live-cell imaging system was developed for visualizing dsRNA in vivo. • It uses dsRNA binding proteins fused with two halves of a fluorescent protein. • Binding to a common dsRNA enables the reporter to become fluorescent. • The system can efficiently monitor viral RNA replication in living cells.

  12. Visualizing double-stranded RNA distribution and dynamics in living cells by dsRNA binding-dependent fluorescence complementation

    Cheng, Xiaofei [Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3 (Canada); College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, Zhejiang 310036 (China); Deng, Ping; Cui, Hongguang [Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3 (Canada); Wang, Aiming, E-mail: aiming.wang@agr.gc.ca [Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3 (Canada)

    2015-11-15

    Double-stranded RNA (dsRNA) is an important type of RNA that plays essential roles in diverse cellular processes in eukaryotic organisms and a hallmark in infections by positive-sense RNA viruses. Currently, no in vivo technology has been developed for visualizing dsRNA in living cells. Here, we report a dsRNA binding-dependent fluorescence complementation (dRBFC) assay that can be used to efficiently monitor dsRNA distribution and dynamics in vivo. The system consists of two dsRNA-binding proteins, which are fused to the N- and C-terminal halves of the yellow fluorescent protein (YFP). Binding of the two fusion proteins to a common dsRNA brings the split YFP halves in close proximity, leading to the reconstitution of the fluorescence-competent structure and restoration of fluorescence. Using this technique, we were able to visualize the distribution and trafficking of the replicative RNA intermediates of positive-sense RNA viruses in living cells. - Highlights: • A live-cell imaging system was developed for visualizing dsRNA in vivo. • It uses dsRNA binding proteins fused with two halves of a fluorescent protein. • Binding to a common dsRNA enables the reporter to become fluorescent. • The system can efficiently monitor viral RNA replication in living cells.

  13. Adaptation of Tri-molecular fluorescence complementation allows assaying of regulatory Csr RNA-protein interactions in bacteria.

    Gelderman, Grant; Sivakumar, Anusha; Lipp, Sarah; Contreras, Lydia

    2015-02-01

    sRNAs play a significant role in controlling and regulating cellular metabolism. One of the more interesting aspects of certain sRNAs is their ability to make global changes in the cell by interacting with regulatory proteins. In this work, we demonstrate the use of an in vivo Tri-molecular Fluorescence Complementation assay to detect and visualize the central regulatory sRNA-protein interaction of the Carbon Storage Regulatory system in E. coli. The Carbon Storage Regulator consists primarily of an RNA binding protein, CsrA, that alters the activity of mRNA targets and of an sRNA, CsrB, that modulates the activity of CsrA. We describe the construction of a fluorescence complementation system that detects the interactions between CsrB and CsrA. Additionally, we demonstrate that the intensity of the fluorescence of this system is able to detect changes in the affinity of the CsrB-CsrA interaction, as caused by mutations in the protein sequence of CsrA. While previous methods have adopted this technique to study mRNA or RNA localization, this is the first attempt to use this technique to study the sRNA-protein interaction directly in bacteria. This method presents a potentially powerful tool to study complex bacterial RNA protein interactions in vivo. © 2014 Wiley Periodicals, Inc.

  14. In vitro and in vivo mapping of the Prunus necrotic ringspot virus coat protein C-terminal dimerization domain by bimolecular fluorescence complementation.

    Aparicio, Frederic; Sánchez-Navarro, Jesús A; Pallás, Vicente

    2006-06-01

    Interactions between viral proteins are critical for virus viability. Bimolecular fluorescent complementation (BiFC) technique determines protein interactions in real-time under almost normal physiological conditions. The coat protein (CP) of Prunus necrotic ringspot virus is required for multiple functions in its replication cycle. In this study, the region involved in CP dimerization has been mapped by BiFC in both bacteria and plant tissue. Full-length and C-terminal deleted forms of the CP gene were fused in-frame to the N- and C-terminal fragments of the yellow fluorescent protein. The BiFC analysis showed that a domain located between residues 9 and 27 from the C-end plays a critical role in dimerization. The importance of this C-terminal region in dimer formation and the applicability of the BiFC technique to analyse viral protein interactions are discussed.

  15. Functional analysis of Ficolin-3 mediated complement activation

    Hein, Estrid; Honoré, Christian; Skjoedt, Mikkel-Ole

    2010-01-01

    Ficolin-3 mediated complement activation that could be applicable for research and clinical use. Bovine serum albumin (BSA) was acetylated (acBSA) and chosen as a solid phase ligand for Ficolins in microtiter wells. Binding of Ficolins on acBSA was evaluated, as was functional complement activation...... was applied to the samples that inhibited interference from the classical pathway due to the presence of anti-BSA antibodies in some sera. We describe a novel functional method for measuring complement activation mediated by Ficolin-3 in human serum up to the formation of TCC. The assay provides...

  16. Combination of Complement-Dependent Cytotoxicity and Relative Fluorescent Quantification of HLA Length Polymorphisms Facilitates the Detection of a Loss of Heterozygosity

    Klaus Witter

    2014-01-01

    Full Text Available Loss of heterozygosity (LOH is a common event in malignant cells. In this work we introduce a new approach to identify patients with loss of heterozygosity in the HLA region either at first diagnosis or after HLA mismatched allogeneic HSCT. Diagnosis of LOH requires a high purity of recipient target cells. FACS is time consuming and also frequently prevented by rather nonspecific or unknown immune phenotype. The approach for recipient cell enrichment is based on HLA targeted complement-dependent cytotoxicity (CDC. Relative fluorescent quantification (RFQ analysis of HLA intron length polymorphisms then allows analysis of HLA heterozygosity. The approach is exemplified in recent clinical cases illustrating the detection of an acquired allele loss. As illustrated in one case with DPB1, distinct HLA loci in donor and patient were sufficient for both proof of donor cell removal and evaluation of allele loss in the patient's leukemic cells. Results were confirmed using HLA-B RFQ analysis and leukemia-associated aberrant immunophenotype (LAIP based cell sort. Both results confirmed suspected loss of HLA heterozygosity. Our approach complements or substitutes for FACS-based cell enrichment; hence it may be further developed as novel routine diagnostic tool. This allows rapid recipient cell purification and testing for loss of HLA heterozygosity before and after allogeneic HSCT in easily accessible peripheral blood samples.

  17. TRANSGENIC STRATEGY FOR IDENTIFYING SYNAPTIC CONNECTIONS IN MICE BY FLUORESCENCE COMPLEMENTATION (GRASP

    Masahito eYamagata

    2012-02-01

    Full Text Available In the "GFP reconstitution across synaptic partners" (GRASP method, non-fluorescent fragments of GFP are expressed in two different neurons; the fragments self-assemble at synapses between the two to form a fluorophore. GRASP has proven useful for light microscopic identification of synapses in two invertebrate species, Caenorhabditis elegans and Drosophila melanogaster, but has not yet been applied to vertebrates. Here, we describe GRASP constructs that function in mammalian cells and implement a transgenic strategy in which a Cre-dependent gene switch leads to expression of the two fragments in mutually exclusive neuronal subsets in mice. Using a transgenic line that expresses Cre selectively in rod photoreceptors, we demonstrate labeling of synapses in the outer plexiform layer of the retina. Labeling is specific, in that synapses made by rods remain labeled for at least 6 months whereas nearby synapses made by intercalated cone photoreceptors on many of the same interneurons remain unlabeled. We also generated antisera that label reconstituted GFP but neither fragment in order to amplify the GRASP signal and thereby increase the sensitivity of the method.

  18. Functional analysis of Ficolin-3 mediated complement activation

    Hein, Estrid; Honoré, Christian Le Fèvre; Skjoedt, Mikkel-Ole

    2010-01-01

    assessed by C4, C3 and terminal complement complex (TCC) deposition. Serum Ficolin-3 bound to acBSA in a calcium dependent manner, while only minimal binding of Ficolin-2 and no binding of Ficolin-1 were observed. No binding to normal BSA was seen for any of the Ficolins. Serum C4, C3 and TCC deposition...... was applied to the samples that inhibited interference from the classical pathway due to the presence of anti-BSA antibodies in some sera. We describe a novel functional method for measuring complement activation mediated by Ficolin-3 in human serum up to the formation of TCC. The assay provides...

  19. Radionuclide X-ray fluorescence analysis

    Cechak, T.

    1994-01-01

    The author's achievements in the title field are summarized and discussed. The following topics are dealt with: (i) principles of radionuclide X-ray fluorescence analysis; (ii) mathematical methods in X-ray fluorescence analysis; (iii) Ross differential filters; (iv) application of radionuclide X-ray fluorescence analysis in the coal industry (with emphasis on the determination of the ash content, sulfur content, and arsenic content of coal); and (v) evaluation of the X-ray fluorescence analyzer from the radiological safety point of view. (P.A.)

  20. Phylogenetic comparative methods complement discriminant function analysis in ecomorphology.

    Barr, W Andrew; Scott, Robert S

    2014-04-01

    In ecomorphology, Discriminant Function Analysis (DFA) has been used as evidence for the presence of functional links between morphometric variables and ecological categories. Here we conduct simulations of characters containing phylogenetic signal to explore the performance of DFA under a variety of conditions. Characters were simulated using a phylogeny of extant antelope species from known habitats. Characters were modeled with no biomechanical relationship to the habitat category; the only sources of variation were body mass, phylogenetic signal, or random "noise." DFA on the discriminability of habitat categories was performed using subsets of the simulated characters, and Phylogenetic Generalized Least Squares (PGLS) was performed for each character. Analyses were repeated with randomized habitat assignments. When simulated characters lacked phylogenetic signal and/or habitat assignments were random, ecomorphology. Copyright © 2013 Wiley Periodicals, Inc.

  1. Complement Test

    ... Salicylates Semen Analysis Serotonin Serum Free Light Chains Sex Hormone Binding Globulin (SHBG) Shiga toxin-producing Escherichia ... and forming complexes that respond to infections, non-self tissues (transplants), dead cells ... KJ. Complement determinations in human disease. Ann Allergy Asthma Immunol . 2004; ...

  2. High throughput screening for antibody induced complement-dependent cytotoxicity in early antibody discovery using homogeneous macroconfocal fluorescence imaging

    Gerritsen, Arnout F.; Bosch, Martijn; de Weers, Michel; van de Winkel, Jan G. J.; Parren, Paul W. H. I.

    2010-01-01

    Complement-dependent cytotoxicity (CDC) represents an important Fc-mediated effector function of antibodies and is a quality often sought in candidates for therapeutic antibody development in cancer. Antibodies inducing potent CDC are relatively rare as the ability to induce CDC is strongly

  3. Automated x-ray fluorescence analysis

    O'Connell, A.M.

    1977-01-01

    A fully automated x-ray fluorescence analytical system is described. The hardware is based on a Philips PW1220 sequential x-ray spectrometer. Software for on-line analysis of a wide range of sample types has been developed for the Hewlett-Packard 9810A programmable calculator. Routines to test the system hardware are also described. (Author)

  4. Functional analysis of the putative peroxidase domain of FANCA, the Fanconi anemia complementation group A protein.

    Ren, J; Youssoufian, H

    2001-01-01

    Fanconi anemia (FA) is an autosomal recessive disorder manifested by chromosomal breakage, birth defects, and susceptibility to bone marrow failure and cancer. At least seven complementation groups have been identified, and the genes defective in four groups have been cloned. The most common subtype is complementation group A. Although the normal functions of the gene products defective in FA cells are not completely understood, a clue to the function of the FA group A gene product (FANCA) was provided by the detection of limited homology in the amino terminal region to a class of heme peroxidases. We evaluated this hypothesis by mutagenesis and functional complementation studies. We substituted alanine residues for the most conserved FANCA residues in the putative peroxidase domain and tested their effects on known biochemical and cellular functions of FANCA. While the substitution mutants were comparable to wild-type FANCA with regard to their stability, subcellular localization, and interaction with FANCG, only the Trp(183)-to-Ala substitution (W183A) abolished the ability of FANCA to complement the sensitivity of FA group A cells to mitomycin C. By contrast, TUNEL assays for apoptosis after exposure to H2O2 showed no differences between parental FA group A cells, cells complemented with wild-type FANCA, and cells complemented with the W183A of FANCA. Moreover, semiquantitative RT-PCR analysis for the expression of the peroxide-sensitive heme oxygenase gene showed appropriate induction after H2O2 exposure. Thus, W183A appears to be essential for the in vivo activity of FANCA in a manner independent of its interaction with FANCG. Moreover, neither wild-type FANCA nor the W183A mutation appears to alter the peroxide-induced apoptosisor peroxide-sensing ability of FA group A cells. Copyright 2001 Academic Press.

  5. Multielement characterization of atmospheric pollutants by x-ray fluorescence analysis and instrumental neutron activation analysis

    Rancitelli, L.A.; Tanner, T.M.

    1976-01-01

    The simultaneous measurement of a wide spectrum of elements in aerosols collected on air filters and in rainwater can yield information on the origin, transport, and removal of atmospheric pollutants. In order to determine the elemental content of these aerosols, a pair of highly sensitive, precise and complementing instrumental techniques, x-ray fluorescence and neutron activation analysis, have been developed and employed. Data are presented on the results of combined x-ray fluorescence and activation analysis of aerosols collected in a number of urban areas of the USA and from the 80th median sampling network in March 1972. From a comparison of these ratios in granite and diabase with those of filters placed in urban areas, it is evident that Zn, Se, Sb, Hg, and Pb levels have been increased by as much as several orders of magnitude. Al, Co, La, Fe, Eu, Sm, Tb, Ta, Hf, and Th appear to exist at levels compatible with an earth's crust origin

  6. Interspecies complementation analysis of xeroderma pigmentosum and UV-sensitive Chinese hamster cells

    Stefanini, M.; Keijzer, W.; Westerveld, A.; Bootsma, D.

    1985-01-01

    Complementation analysis was performed 24 h after fusion of UV-sensitive CHO cells (CHO 12 RO) with XP cells of complementation groups A, B, C, D, F and G. The parental cells are characterized by low levels of unscheduled DNA synthesis (UDS). In all combinations, the UDS levels observed in heterokaryons were higher than those in parental mutant cells, clearly indicating cooperation of human and Chinese hamster repair functions. In heterokaryons of CHO 12 RO with XP-A and XP-C cells, the UDS values reached about the normal human level, whereas in heterokaryons with XP-B, XP-D and XP-F, UDS was restored at a level approaching that in wild-type CHO cells. The results obtained after fusion of CHO cells with two representative cell strains from the XP-G group, XP 2 BI and XP 3 BR, were inconsistent. Fusion with XP 3 BR cells yielded UDS levels ranging from wild-type Chinese hamster to normal human, whereas fusion with XP 2 BI cells resulted in a slight increase in UDS which even after 48 h remained below the level found in wild-type CHO cells. The occurrence of complementation in these interspecies heterokaryons indicates that the genetic defect in the CHO 12 RO cells is different from the defects in the XP complementation groups tested

  7. [Fluorescence spectra analysis of the scrophularia soup].

    Yan, Li-hua; Song, Feng; Han, Juan; Su, Jing; Qu, Fei-fei; Song, Yi-zhan; Hu, Bo-lin; Tian, Jian-guo

    2008-08-01

    The cold-water and boiled-water soaked scrophularia soups have been prepared. The emission and excitation spectra of each scrophularia soup under different conditions have been measured at room temperature. The pH values of the different scrophularia soups have been also detected. There are obvious differences between the cold-water soaked scrophularia soup and the boiled-water soaked scrophularia. For both soups the emission wavelength increases with the wavelength of the excitation, but the peaks of the emission spectra for cold-water and boiled-water soaked scrophularia soup are different, which are 441 and 532 nm, respectively. Excitation spectrum has double peaks in the cold-water soaked scrophularia soup while only one peak with longer wavelength in the boiled-water soaked one. The pH value changes from 5.5 to 4.1. According to the organic admixture fluorescence mechanism we analyzed the reasons of the experimental results. Through heating, the interaction in different fluorescence molecular and the energy transfer process in the same fluorescence molecular become more active, and the conjugate structures and the generation of hydrogen bonds, increase. The fluorescence measurement is of value for the scrophularia pharmacology analysis and provides an analytical method for the quality identification of scrophularia soup.

  8. Status analysis: A complement or an alternative to the class analysis

    Antonić Slobodan

    2009-01-01

    Full Text Available The author discusses the relation between stratification and belonging to the status groups based on citizenship, race, gender or lifestyle (underclass. The author claims that the status analysis is not an alternative, but a complement to the class analysis. The life prospects of individuals in today's society depend not only on their position in the market (or in the system of production, but on their membership of a particular status group as well. Hence the Weberian approach - with two-dimensional, class and status analysis - is certainly more successful in dealing with all the complexities of social reality than the Marxist one. Therefore, if we add the third dimension of the Weber's stratification scheme - power, we can see that the exact social position of the individual could be determined the best by identification of its: position in the market (and the financial equivalent of the outcomes from it; position in a status group; and position in organizational structures (belonging to an organization and position that it occupies. Landowner or wage earner, citizen or immigrant, union activists or non-member, each of these positions mean a position either higher or lower on the stratification ladder. How this three-dimensional approach could be united into a single analytical matrix, and how could successful operationalization of it through appropriate indicators be made, still remains a challenge for researchers and statisticians. .

  9. Schur Complement Reduction in the Mixed-Hybrid Approximation of Darcy's Law: Rounding Error Analysis

    Maryška, Jiří; Rozložník, Miroslav; Tůma, Miroslav

    2000-01-01

    Roč. 117, - (2000), s. 159-173 ISSN 0377-0427 R&D Projects: GA AV ČR IAA2030706; GA ČR GA201/98/P108 Institutional research plan: AV0Z1030915 Keywords : potential fluid flow problem * symmetric indefinite linear systems * Schur complement reduction * iterative methods * rounding error analysis Subject RIV: BA - General Mathematics Impact factor: 0.455, year: 2000

  10. Live cell imaging of interactions between replicase and capsid protein of Brome mosaic virus using Bimolecular Fluorescence Complementation: implications for replication and genome packaging.

    Chaturvedi, Sonali; Rao, A L N

    2014-09-01

    In Brome mosaic virus, it was hypothesized that a physical interaction between viral replicase and capsid protein (CP) is obligatory to confer genome packaging specificity. Here we tested this hypothesis by employing Bimolecular Fluorescent Complementation (BiFC) as a tool for evaluating protein-protein interactions in living cells. The efficacy of BiFC was validated by a known interaction between replicase protein 1a (p1a) and protein 2a (p2a) at the endoplasmic reticulum (ER) site of viral replication. Additionally, co-expression in planta of a bona fide pair of interacting protein partners of p1a and p2a had resulted in the assembly of a functional replicase. Subsequent BiFC assays in conjunction with mCherry labeled ER as a fluorescent cellular marker revealed that CP physically interacts with p2a, but not p1a, and this CP:p2a interaction occurs at the cytoplasmic phase of the ER. The significance of the CP:p2a interaction in BMV replication and genome packaging is discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Live cell imaging of interactions between replicase and capsid protein of Brome mosaic virus using Bimolecular Fluorescence Complementation: Implications for replication and genome packaging

    Chaturvedi, Sonali; Rao, A.L.N.

    2014-01-01

    In Brome mosaic virus, it was hypothesized that a physical interaction between viral replicase and capsid protein (CP) is obligatory to confer genome packaging specificity. Here we tested this hypothesis by employing Bimolecular Fluorescent Complementation (BiFC) as a tool for evaluating protein–protein interactions in living cells. The efficacy of BiFC was validated by a known interaction between replicase protein 1a (p1a) and protein 2a (p2a) at the endoplasmic reticulum (ER) site of viral replication. Additionally, co-expression in planta of a bona fide pair of interacting protein partners of p1a and p2a had resulted in the assembly of a functional replicase. Subsequent BiFC assays in conjunction with mCherry labeled ER as a fluorescent cellular marker revealed that CP physically interacts with p2a, but not p1a, and this CP:p2a interaction occurs at the cytoplasmic phase of the ER. The significance of the CP:p2a interaction in BMV replication and genome packaging is discussed. - Highlights: • YFP fusion proteins of BMV p1a and p2a are biologically active. • Self-interaction was observed for p1a, p2a and CP. • CP interacts with p2a but not p1a. • Majority of reconstituted YFP resulting from bona fide fusion protein partners localized on ER

  12. Live cell imaging of interactions between replicase and capsid protein of Brome mosaic virus using Bimolecular Fluorescence Complementation: Implications for replication and genome packaging

    Chaturvedi, Sonali; Rao, A.L.N., E-mail: arao@ucr.edu

    2014-09-15

    In Brome mosaic virus, it was hypothesized that a physical interaction between viral replicase and capsid protein (CP) is obligatory to confer genome packaging specificity. Here we tested this hypothesis by employing Bimolecular Fluorescent Complementation (BiFC) as a tool for evaluating protein–protein interactions in living cells. The efficacy of BiFC was validated by a known interaction between replicase protein 1a (p1a) and protein 2a (p2a) at the endoplasmic reticulum (ER) site of viral replication. Additionally, co-expression in planta of a bona fide pair of interacting protein partners of p1a and p2a had resulted in the assembly of a functional replicase. Subsequent BiFC assays in conjunction with mCherry labeled ER as a fluorescent cellular marker revealed that CP physically interacts with p2a, but not p1a, and this CP:p2a interaction occurs at the cytoplasmic phase of the ER. The significance of the CP:p2a interaction in BMV replication and genome packaging is discussed. - Highlights: • YFP fusion proteins of BMV p1a and p2a are biologically active. • Self-interaction was observed for p1a, p2a and CP. • CP interacts with p2a but not p1a. • Majority of reconstituted YFP resulting from bona fide fusion protein partners localized on ER.

  13. Characterization and expression analysis of a complement component gene in sea cucumber ( Apostichopus japonicus)

    Chen, Zhong; Zhou, Zunchun; Yang, Aifu; Dong, Ying; Guan, Xiaoyan; Jiang, Bei; Wang, Bai

    2015-12-01

    The complement system plays a crucial role in the innate immune system of animals. It can be activated by distinct yet overlapping classical, alternative and lectin pathways. In the alternative pathway, complement factor B (Bf) serves as the catalytic subunit of complement component 3 (C3) convertase, which plays the central role among three activation pathways. In this study, the Bf gene in sea cucumber ( Apostichopus japonicus), termed AjBf, was obtained by rapid amplification of cDNA ends (RACE). The full-length cDNA of AjBf was 3231 bp in length barring the poly (A) tail. It contained an open reading frame (ORF) of 2742 bp encoding 913 amino acids, a 105 bp 5'-UTR (5'-terminal untranslated region) and a 384 bp 3'-UTR. AjBf was a mosaic protein with six CCP (complement control protein) domains, a VWA (von Willebrand factor A) domain, and a serine protease domain. The deduced molecular weight of AjBf protein was 101 kDa. Quantitative real time PCR (qRT-PCR) analysis indicated that the expression level of AjBf in A. japonicus was obviously higher at larval stage than that at embryonic stage. Expression detection in different tissues showed that AjBf expressed higher in coelomocytes than in other four tissues. In addation, AjBf expression in different tissues was induced significantly after LPS or PolyI:C challenge. These results indicated that AjBf plays an important role in immune responses to pathogen infection.

  14. Capacity of X-ray fluorescence analysis

    Wobrauschek, P.; Kregsamer, P.

    1997-01-01

    X-Ray fluorescence analysis (XRF) is a powerful analytical tool for the qualitative and quantitative determination of chemical elements in a sample. Two different detection principles are accepted widely: wavelength dispersive and energy dispersive. Various sources for XRF are discussed: X-ray tubes, accelerators for particle induced XRF, radioactive isotopes, and the use of synchrotron radiation. Applications include environmental, technical, medical, fine art, and forensic studies. Due to the demands of research and application special techniques like total reflection XRF (TXRF) were developed with ultimately achievable detection limits in the femtogram region. The elements detectable by XRF range from Be to U. (author)

  15. Total reflection X-ray fluorescence analysis

    Michaelis, W.; Prange, A.

    1987-01-01

    In the past few years, total reflection X-ray flourescence analysis (TXRF) has found an increasing number of assignments and applications. Experience of trace element analysis using TXRF and examples of applications are already widespread. Therefore, users of TXRF had the opportunity of an intensive exchange of their experience at the 1st workshop on total reflection X-ray fluorescence analysis which took place on May 27th and 28th 1986 at the GKSS Research Centre at Geesthacht. In a series of lectures and discussions dealing with the analytical principle itself, sample preparation techniques and applications as well as comuter programs for spectrum evaluation, the present state of development and the range of applications were outlined. 3 studies out of a total of 14 were included separately in the INIS and ENERGY databases. With 61 figs., 12 tabs [de

  16. In vivo X-ray fluorescence analysis

    Ahlgren, L.

    1980-02-01

    Measurements on five occupationally exposed persons have shown that it is possible to use X-ray fluorescence analysis for in vivo measurements of lead in the skeleton. The technique for calibrating in vivo X-ray fluorescence measurements of lead in bone tissue has been studied in detail and a two-component phantom simulating the bone and the soft tissue parts of the finger constructed. The technique has been used for in vivo measurements on 22 occupationally exposed persons. The minimum detectable concentration of lead in fingerbones was found to be around 20 μg x g -1 . The lead concentrations in their skeletons and blood were compared: the correlation was poor. The variations in lead concentrations in the skeleton have been studied in occupationally exposed persons and in samples from archaeological skeletons. The sensitivity and the minimum detectable concentration of cadmium in the kidney cortex in in vivo measurements has been studied by measurements on kidney models. The minimum detectable concentration was 20 μg x g -1 at a skin-kidney distance of 30 mm and 40 μg x g -1 at 40 mm. Five persons occupationally exposed were studied. (Author)

  17. Complement in patients receiving maintenance hemodialysis: functional screening and quantitative analysis

    Horikoshi Satoshi

    2010-12-01

    Full Text Available Abstract Background The complement system is vital for innate immunity and is implicated in the pathogenesis of inflammatory diseases and the mechanism of host defense. Complement deficiencies occasionally cause life-threatening diseases. In hemodialysis (HD patients, profiles on complement functional activity and deficiency are still obscure. The objectives of the present study were to measure the functional complement activities of the classical pathway (CP, lectin pathway (LP and alternative pathway (AP using a novel method and consequently to elucidate the rates of deficiencies among HD patients. Methods In the present study, 244 HD patients at one dialysis center and 204 healthy controls were enrolled. Functional complement activities were measured simultaneously using the Wielisa®-kit. The combination of the results of these three pathway activities allows us to speculate which candidate complement is deficient; subsequently, the deficient complement was determined. Results All three functional complement activities were significantly higher in the HD patients than in the control group (P ®-kit, 16 sera (8.8% with mannose-binding lectin (MBL deficiency, 1 serum (0.4% with C4 deficiency, 1 serum (0.4% with C9 deficiency, and 1 serum (0.4% with B deficiency were observed in the HD group, and 18 sera (8.8% with MBL deficiency and 1 serum (0.5% with B deficiency were observed in the control group. There were no significant differences in the 5-year mortality rate between each complement-deficient group and the complement-sufficient group among the HD patients. Conclusion This is the first report that profiles complement deficiencies by simultaneous measurement of functional activities of the three complement pathways in HD patients. Hemodialysis patients frequently suffer from infections or malignancies, but functional complement deficiencies do not confer additional risk of mortality.

  18. X-ray fluorescence method for trace analysis and imaging

    Hayakawa, Shinjiro

    2000-01-01

    X-ray fluorescence analysis has a long history as conventional bulk elemental analysis with medium sensitivity. However, with the use of synchrotron radiation x-ray fluorescence method has become a unique analytical technique which can provide tace elemental information with the spatial resolution. To obtain quantitative information of trace elemental distribution by using the x-ray fluorescence method, theoretical description of x-ray fluorescence yield is described. Moreover, methods and instruments for trace characterization with a scanning x-ray microprobe are described. (author)

  19. Sheet Fluorescence and Annular Analysis of Ultracold Neutral Plasmas

    Castro, J.; Gao, H.; Killian, T. C.

    2009-01-01

    Annular analysis of fluorescence imaging measurements on Ultracold Neutral Plasmas (UNPs) is demonstrated. Spatially-resolved fluorescence imaging of the strontium ions produces a spectrum that is Doppler-broadened due to the thermal ion velocity and shifted due to the ion expansion velocity. The fluorescence excitation beam is spatially narrowed into a sheet, allowing for localized analysis of ion temperatures within a volume of the plasma with small density variation. Annular analysis of fluorescence images permits an enhanced signal-to-noise ratio compared to previous fluorescence measurements done in strontium UNPs. Using this technique and analysis, plasma ion temperatures are measured and shown to display characteristics of plasmas with strong coupling such as disorder induced heating and kinetic energy oscillations.

  20. The fluorescence properties and NMR analysis of protopine and allocryptopine

    Kubala, Martin; Vacek, Jan; Popa, Igor; Janovska, Marika; Kosina, Pavel; Ulrichova, Jitka; Travnicek, Zdenek; Simanek, Vilim

    2011-01-01

    The fluorescence properties of protopine and allocryptopine in aqueous and organic environments are described for the first time. The fluorescence of alkaloids and their pH-dependent interconversion to cationic forms (transannular interaction) were studied using steady-state and time-resolved fluorescence techniques. For the analysis of tricyclic base and cis/trans tetracyclic cations of the alkaloids, NMR and X-ray crystallography were used. - Highlights: → We describe fundamental fluorescence characteristics of alkaloids protopine and allocryptopine. → We analyzed the pH-dependent transitions and cis/trans isomerization. → These two alkaloids can be better distinguished by their fluorescence decay characteristics. → The fluorescence parameters are related to the NMR and crystallographic structural data.

  1. Applications of optical fiber to the remote fluorescence analysis

    Shin, Jang Soo; Kim, Duck Hueon; Lee, Soo Ho

    1992-12-01

    The laser fluorometer developed in 1987 has been used in real circumstances for trace uranium analysis. And, we have been trying to improve the instrument to be able to apply in analytical circumstances of remote measurement using optical fiber. The N 2 laser beam and the resulting fluorescence light could be successfully transmitted through a quartz-made optical fiber. The wavelength resolution and the fluorescence decay time resolution induced by pulsed N 2 laser were used to the uranium fluorescence analyses. The fluorescence of uranium in nitric acid medium was measured successfully using the system. The fluorescence signal was analysed using simplex method which is useful to deconvolute the mixed signals. An analytical method using thermal lens effect was developed. The method will be a complementary one for the fluorescence measurement. (Author)

  2. Scanning fluorescent microscopy is an alternative for quantitative fluorescent cell analysis.

    Varga, Viktor Sebestyén; Bocsi, József; Sipos, Ferenc; Csendes, Gábor; Tulassay, Zsolt; Molnár, Béla

    2004-07-01

    Fluorescent measurements on cells are performed today with FCM and laser scanning cytometry. The scientific community dealing with quantitative cell analysis would benefit from the development of a new digital multichannel and virtual microscopy based scanning fluorescent microscopy technology and from its evaluation on routine standardized fluorescent beads and clinical specimens. We applied a commercial motorized fluorescent microscope system. The scanning was done at 20 x (0.5 NA) magnification, on three channels (Rhodamine, FITC, Hoechst). The SFM (scanning fluorescent microscopy) software included the following features: scanning area, exposure time, and channel definition, autofocused scanning, densitometric and morphometric cellular feature determination, gating on scatterplots and frequency histograms, and preparation of galleries of the gated cells. For the calibration and standardization Immuno-Brite beads were used. With application of shading compensation, the CV of fluorescence of the beads decreased from 24.3% to 3.9%. Standard JPEG image compression until 1:150 resulted in no significant change. The change of focus influenced the CV significantly only after +/-5 microm error. SFM is a valuable method for the evaluation of fluorescently labeled cells. Copyright 2004 Wiley-Liss, Inc.

  3. Mutations in complement regulatory proteins predispose to preeclampsia: a genetic analysis of the PROMISSE cohort.

    Jane E Salmon

    2011-03-01

    Full Text Available Pregnancy in women with systemic lupus erythematosus (SLE or antiphospholipid antibodies (APL Ab--autoimmune conditions characterized by complement-mediated injury--is associated with increased risk of preeclampsia and miscarriage. Our previous studies in mice indicate that complement activation targeted to the placenta drives angiogenic imbalance and placental insufficiency.We use PROMISSE, a prospective study of 250 pregnant patients with SLE and/or APL Ab, to test the hypothesis in humans that impaired capacity to limit complement activation predisposes to preeclampsia. We sequenced genes encoding three complement regulatory proteins--membrane cofactor protein (MCP, complement factor I (CFI, and complement factor H (CFH--in 40 patients who had preeclampsia and found heterozygous mutations in seven (18%. Five of these patients had risk variants in MCP or CFI that were previously identified in atypical hemolytic uremic syndrome, a disease characterized by endothelial damage. One had a novel mutation in MCP that impairs regulation of C4b. These findings constitute, to our knowledge, the first genetic defects associated with preeclampsia in SLE and/or APL Ab. We confirmed the association of hypomorphic variants of MCP and CFI in a cohort of non-autoimmune preeclampsia patients in which five of 59 were heterozygous for mutations.The presence of risk variants in complement regulatory proteins in patients with SLE and/or APL Ab who develop preeclampsia, as well as in preeclampsia patients lacking autoimmune disease, links complement activation to disease pathogenesis and suggests new targets for treatment of this important public health problem.ClinicalTrials.gov NCT00198068.

  4. Analysis of Cholesterol Trafficking with Fluorescent Probes

    Maxfield, Frederick R.; Wustner, Daniel

    2012-01-01

    Cholesterol plays an important role in determining the biophysical properties of biological membranes, and its concentration is tightly controlled by homeostatic processes. The intracellular transport of cholesterol among organelles is a key part of the homeostatic mechanism, but sterol transport...... that can bind to cholesterol to reveal its distribution in cells. We also discuss the use of intrinsically fluorescent sterols that closely mimic cholesterol, as well as some minimally modified fluorophore-labeled sterols. Methods for imaging these sterols by conventional fluorescence microscopy...... and by multiphoton microscopy are described. Some label-free methods for imaging cholesterol itself are also discussed briefly....

  5. Analysis of different DNA fragments of Corynebacterium glutamicum complementing dapE of Escherichia coli.

    Wehrmann, A; Eggeling, L; Sahm, H

    1994-12-01

    In Corynebacterium glutamicum L-lysine is synthesized simultaneously via the succinylase and dehydrogenase variant of the diaminopimelate pathway. Starting from a strain with a disrupted dehydrogenase gene, three different-sized DNA fragments were isolated which complemented defective Escherichia coli mutants in the succinylase pathway. Enzyme studies revealed that in one case the dehydrogenase gene had apparently been reconstituted in the heterologous host. The two other fragments resulted in desuccinylase activity; one of them additionally in succinylase activity. However, the physical analysis showed that structural changes had taken place in all fragments. Using a probe derived from one of the fragments we isolated a 3.4 kb BamHI DNA fragment without selective pressure (by colony hybridization). This was structurally intact and proved functionally to result in tenfold desuccinylase overexpression. The nucleotide sequence of a 1966 bp fragment revealed the presence of one truncated open reading frame of unknown function and that of dapE encoding N-succinyl diaminopimelate desuccinylase (EC 3.5.1.18). The deduced amino acid sequence of the dapE gene product shares 23% identical residues with that from E. coli. The C. glutamicum gene now available is the first gene from the succinylase branch of lysine synthesis of this biotechnologically important organism.

  6. Quantitative image analysis of cellular heterogeneity in breast tumors complements genomic profiling.

    Yuan, Yinyin; Failmezger, Henrik; Rueda, Oscar M; Ali, H Raza; Gräf, Stefan; Chin, Suet-Feung; Schwarz, Roland F; Curtis, Christina; Dunning, Mark J; Bardwell, Helen; Johnson, Nicola; Doyle, Sarah; Turashvili, Gulisa; Provenzano, Elena; Aparicio, Sam; Caldas, Carlos; Markowetz, Florian

    2012-10-24

    Solid tumors are heterogeneous tissues composed of a mixture of cancer and normal cells, which complicates the interpretation of their molecular profiles. Furthermore, tissue architecture is generally not reflected in molecular assays, rendering this rich information underused. To address these challenges, we developed a computational approach based on standard hematoxylin and eosin-stained tissue sections and demonstrated its power in a discovery and validation cohort of 323 and 241 breast tumors, respectively. To deconvolute cellular heterogeneity and detect subtle genomic aberrations, we introduced an algorithm based on tumor cellularity to increase the comparability of copy number profiles between samples. We next devised a predictor for survival in estrogen receptor-negative breast cancer that integrated both image-based and gene expression analyses and significantly outperformed classifiers that use single data types, such as microarray expression signatures. Image processing also allowed us to describe and validate an independent prognostic factor based on quantitative analysis of spatial patterns between stromal cells, which are not detectable by molecular assays. Our quantitative, image-based method could benefit any large-scale cancer study by refining and complementing molecular assays of tumor samples.

  7. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, J.; Koleška, M.; Voljanskij, A.

    2015-01-01

    Mercury is an essential component of fluorescent lamps. Not all fluorescent lamps are recycled, resulting in contamination of the environment with toxic mercury, making measurement of the mercury mass used in fluorescent lamps important. Mercury mass measurement of lamps via instrumental neutron activation analysis (NAA) was tested under various conditions in the LVR-15 research reactor. Fluorescent lamps were irradiated in different positions in vertical irradiation channels and a horizontal channel in neutron fields with total fluence rates from 3×10 8 cm −2 s −1 to 10 14 cm −2 s −1 . The 202 Hg(n,γ) 203 Hg nuclear reaction was used for mercury mass evaluation. Activities of 203 Hg and others induced radionuclides were measured via gamma spectrometry with an HPGe detector at various times after irradiation. Standards containing an Hg 2 Cl 2 compound were used to determine mercury mass. Problems arise from the presence of elements with a large effective cross section in luminescent material (europium, antimony and gadolinium) and glass (boron). The paper describes optimization of the NAA procedure in the LVR-15 research reactor with particular attention to influence of neutron self-absorption in fluorescent lamps. - Highlights: • Mercury is an essential component of fluorescent lamps. • Fluorescent lamps were irradiated in neutron fields in research reactor. • 203 Hg induced radionuclide activity was measured using gamma spectrometry. • Mercury mass in fluorescent lamps can be measured by neutron activation analysis.

  8. Transcriptome Analysis of the Innate Immunity-Related Complement System in Spleen Tissue of Ctenopharyngodon idella Infected with Aeromonas hydrophila.

    Yunfei Dang

    Full Text Available The grass carp (Ctenopharyngodon idella is an important commercial farmed herbivorous fish species in China, but is susceptible to Aeromonas hydrophila infections. In the present study, we performed de novo RNA-Seq sequencing of spleen tissue from specimens of a disease-resistant family, which were given intra-peritoneal injections containing PBS with or without a dose of A. hydrophila. The fish were sampled from the control group at 0 h, and from the experimental group at 4, 8, 12, 24, 48 and 72 h. 122.18 million clean reads were obtained from the normalized cDNA libraries; these were assembled into 425,260 contigs and then 191,795 transcripts. Of those, 52,668 transcripts were annotated with the NCBI Nr database, and 41,347 of the annotated transcripts were assigned into 90 functional groups. 20,569 unigenes were classified into six main categories, including 38 secondary KEGG pathways. 2,992 unigenes were used in the analysis of differentially expressed genes (DEGs. 89 of the putative DEGs were related to the immune system and 41 of them were involved in the complement and coagulation cascades pathway. This study provides insights into the complement and complement-related pathways involved in innate immunity, through expression profile analysis of the genomic resources in C. idella. We conclude that complement and complement-related genes play important roles during defense against A. hydrophila infection. The immune response is activated at 4 h after the bacterial injections, indicating that the complement pathways are activated at the early stage of bacterial infection. The study has improved our understanding of the immune response mechanisms in C. idella to bacterial pathogens.

  9. 5-ALA induced fluorescent image analysis of actinic keratosis

    Cho, Yong-Jin; Bae, Youngwoo; Choi, Eung-Ho; Jung, Byungjo

    2010-02-01

    In this study, we quantitatively analyzed 5-ALA induced fluorescent images of actinic keratosis using digital fluorescent color and hyperspectral imaging modalities. UV-A was utilized to induce fluorescent images and actinic keratosis (AK) lesions were demarcated from surrounding the normal region with different methods. Eight subjects with AK lesion were participated in this study. In the hyperspectral imaging modality, spectral analysis method was utilized for hyperspectral cube image and AK lesions were demarcated from the normal region. Before image acquisition, we designated biopsy position for histopathology of AK lesion and surrounding normal region. Erythema index (E.I.) values on both regions were calculated from the spectral cube data. Image analysis of subjects resulted in two different groups: the first group with the higher fluorescence signal and E.I. on AK lesion than the normal region; the second group with lower fluorescence signal and without big difference in E.I. between two regions. In fluorescent color image analysis of facial AK, E.I. images were calculated on both normal and AK lesions and compared with the results of hyperspectral imaging modality. The results might indicate that the different intensity of fluorescence and E.I. among the subjects with AK might be interpreted as different phases of morphological and metabolic changes of AK lesions.

  10. Possibilities of radioisotopic fluorescence analysis application in copper industry

    Parus, J.; Kierzek, J.

    1983-01-01

    The main applications of X-ray fluorescence analysis in copper industry such as: copper ores and other materials from flotation analysis, lead and silver determination in blister copper, analysis of metallurgic dusts and copper base alloys analysis are presented. (A.S.)

  11. How Content Analysis may Complement and Extend the Insights of Discourse Analysis

    Tracey Feltham-King

    2016-02-01

    Full Text Available Although discourse analysis is a well-established qualitative research methodology, little attention has been paid to how discourse analysis may be enhanced through careful supplementation with the quantification allowed in content analysis. In this article, we report on a research study that involved the use of both Foucauldian discourse analysis (FDA and directed content analysis based on social constructionist theory and our qualitative research findings. The research focused on the discourses deployed, and the ways in which women were discursively positioned, in relation to abortion in 300 newspaper articles, published in 25 national and regional South African newspapers over 28 years, from 1978 to 2005. While the FDA was able to illuminate the constitutive network of power relations constructing women as subjects of a particular kind, questions emerged that were beyond the scope of the FDA. These questions concerned understanding the relative weightings of various discourses and tracing historical changes in the deployment of these discourses. In this article, we show how the decision to combine FDA and content analysis affected our sampling methodology. Using specific examples, we illustrate the contribution of the FDA to the study. Then, we indicate how subject positioning formed the link between the FDA and the content analysis. Drawing on the same examples, we demonstrate how the content analysis supplemented the FDA through tracking changes over time and providing empirical evidence of the extent to which subject positionings were deployed.

  12. Characterization of shark complement factor I gene(s): genomic analysis of a novel shark-specific sequence.

    Shin, Dong-Ho; Webb, Barbara M; Nakao, Miki; Smith, Sylvia L

    2009-07-01

    Complement factor I is a crucial regulator of mammalian complement activity. Very little is known of complement regulators in non-mammalian species. We isolated and sequenced four highly similar complement factor I cDNAs from the liver of the nurse shark (Ginglymostoma cirratum), designated as GcIf-1, GcIf-2, GcIf-3 and GcIf-4 (previously referred to as nsFI-a, -b, -c and -d) which encode 689, 673, 673 and 657 amino acid residues, respectively. They share 95% (shark-specific sequence between the leader peptide (LP) and the factor I membrane attack complex (FIMAC) domain. The cDNA sequences differ only in the size and composition of the shark-specific region (SSR). Sequence analysis of each SSR has identified within the region two novel short sequences (SS1 and SS2) and three repeat sequences (RS1-3). Genomic analysis has revealed the existence of three introns between the leader peptide and the FIMAC domain, tentatively designated intron 1, intron 2, and intron 3 which span 4067, 2293 and 2082bp, respectively. Southern blot analysis suggests the presence of a single gene copy for each cDNA type. Phylogenetic analysis suggests that complement factor I of cartilaginous fish diverged prior to the emergence of mammals. All four GcIf cDNA species are expressed in four different tissues and the liver is the main tissue in which expression level of all four is high. This suggests that the expression of GcIf isotypes is tissue-dependent.

  13. Power flow as a complement to statistical energy analysis and finite element analysis

    Cuschieri, J. M.

    1987-01-01

    Present methods of analysis of the structural response and the structure-borne transmission of vibrational energy use either finite element (FE) techniques or statistical energy analysis (SEA) methods. The FE methods are a very useful tool at low frequencies where the number of resonances involved in the analysis is rather small. On the other hand SEA methods can predict with acceptable accuracy the response and energy transmission between coupled structures at relatively high frequencies where the structural modal density is high and a statistical approach is the appropriate solution. In the mid-frequency range, a relatively large number of resonances exist which make finite element method too costly. On the other hand SEA methods can only predict an average level form. In this mid-frequency range a possible alternative is to use power flow techniques, where the input and flow of vibrational energy to excited and coupled structural components can be expressed in terms of input and transfer mobilities. This power flow technique can be extended from low to high frequencies and this can be integrated with established FE models at low frequencies and SEA models at high frequencies to form a verification of the method. This method of structural analysis using power flo and mobility methods, and its integration with SEA and FE analysis is applied to the case of two thin beams joined together at right angles.

  14. Organic characterisation of cave drip water by LC-OCD and fluorescence analysis

    Rutlidge, Helen; Andersen, Martin S.; Baker, Andy; Chinu, Khorshed J.; Cuthbert, Mark O.; Jex, Catherine N.; Marjo, Christopher E.; Markowska, Monika; Rau, Gabriel C.

    2015-10-01

    Cathedral Cave, Wellington, Australia, is a natural laboratory for studying water movement and geochemical processes in the unsaturated zone by using artificial irrigation to activate drip sites within the cave. Water sampled from two drip sites activated by irrigations carried out in summer 2014 was analysed for dissolved inorganic ions and fluorescent organic matter. The analysis allowed the development of a conceptual flow path model for each drip site. DOM analysis was further complemented by liquid chromatography with organic carbon detection (LC-OCD), applied for the first time to karst drip waters, allowing the characterisation of six organic matter fractions. The differences in organic matter fractions at each drip site are interpreted as a signature of the proposed flow paths. LC-OCD was also compared with parallel factor analysis (PARAFAC) of the fluorescence and good correlations were observed for high molecular weight organic matter. Strong positive correlations were also observed for high molecular weight matter and Cu and Ni. This is suggestive of colloidal transport of Cu and Ni by organic matter with high molecular weight, while small molecular weight colloids were not efficient transporters. LC-OCD uniquely provides information on non-fluorescent organic matter and can be used to further quantify drip water organic matter composition.

  15. X-ray fluorescent elemental analysis. Ch. 16

    Baryshev, V.; Kulipanov, G.; Skrinsky, A.

    1991-01-01

    X-ray fluorescence analysis (XFA) is used worldwide to define a quantitative content of the elements as well as to visualize the distribution of elements in different regions (element mapping). Utilization of synchrotron radiation (SR) to excite X-ray fluorescence enables the XFA method to be qualitatively improved. This chapter reviews the experimental work in especially the last decade (author). 71 refs.; 24 figs.; 3 tabs

  16. Detection of Heteromers Formed by Cannabinoid CB1, Dopamine D2, and Adenosine A2A G-Protein-Coupled Receptors by Combining Bimolecular Fluorescence Complementation and Bioluminescence Energy Transfer

    Navarro, Gemma; Carriba, Paulina; Gandí, Jorge; Ciruela, Francisco; Casadó, Vicent; Cortés, Antoni; Mallol, Josefa; Canela, Enric I.; Lluis, Carmen; Franco, Rafael

    2008-01-01

    Functional interactions in signaling occur between dopamine D2 (D2R) and cannabinoid CB1 (CB1R) receptors, between CB1R and adenosine A2A (A2AR) receptors, and between D2R and A2AR. Furthermore, direct molecular interactions have been reported for the pairs CB1R-D2R, A2AR-D2R, and CB1R-A2AR. Here a combination of bimolecular fluorescence complementation and bioluminescence energy transfer techniques was used to identify the occurrence of D2R-CB1R-A2AR hetero-oligomers in living cells. PMID:18956124

  17. Detection of Heteromers Formed by Cannabinoid CB1, Dopamine D2, and Adenosine A2A G-Protein-Coupled Receptors by Combining Bimolecular Fluorescence Complementation and Bioluminescence Energy Transfer

    Gemma Navarro

    2008-01-01

    Full Text Available Functional interactions in signaling occur between dopamine D2 (D2R and cannabinoid CB1 (CB1R receptors, between CB1R and adenosine A2A (A2AR receptors, and between D2R and A2AR. Furthermore, direct molecular interactions have been reported for the pairs CB1R-D2R, A2AR-D2R, and CB1R-A2AR. Here a combination of bimolecular fluorescence complementation and bioluminescence energy transfer techniques was used to identify the occurrence of D2R-CB1R-A2AR hetero-oligomers in living cells.

  18. A single-chip computer analysis system for liquid fluorescence

    Zhang Yongming; Wu Ruisheng; Li Bin

    1998-01-01

    The single-chip computer analysis system for liquid fluorescence is an intelligent analytic instrument, which is based on the principle that the liquid containing hydrocarbons can give out several characteristic fluorescences when irradiated by strong light. Besides a single-chip computer, the system makes use of the keyboard and the calculation and printing functions of a CASIO printing calculator. It combines optics, mechanism and electronics into one, and is small, light and practical, so it can be used for surface water sample analysis in oil field and impurity analysis of other materials

  19. Applications of optical fiber to remote laser fluorescence analysis

    Kim, Cheol Jung; Shin, Jang Soo; Lee, Sang Mock; Kim, Jeong Moog; Kim, Duk Heon; Hong, Seok Kyung

    1991-12-01

    Fluorescence analysis using time-resolved laser fluorimetry has been used for trace uranium analysis because this method shows high sensitivity and low detection limit and is less matrix dependent than any other fluorimetric measurement. By this time, the uranium analyses in the solution of reprocessing process or high radioactive area have been primarily analyzed by sampling of the solution, but recently, a study on a remote uranium fluorescence analysis using optical fiber has been setting out based on the development of an optical fiber with radiation resistivity and of an advanced laser excitation source. Laser fluorimetry developed by our laboratory for trace uranium analyses in uranium handling process or in urine samples of workers in a nuclear facility has been used in our institute since 1988. A development of the system for remote control of uranium fluorescence analysis will be expected to contribute to an on-line uranium concentration monitoring in the cooling water of reconversion stream. In this report, we summarize the information related to fluorescence analyses and remote fluorescence monitoring methods established by foreign countries and our laboratory. We also present a future research direction for remote on-line monitoring of uranium in conversion or reconversion process. (Author)

  20. Research Note: Energy dispersive x-ray fluorescence analysis ...

    Energy Dispersive X-Ray fluorescence (EDXRF) technique for the analysis of geological, biological and environmental samples is described. The technique has been applied in the analysis of 10 (geological, biological, environmental) standard reference materials. The accuracy and precision of the technique were attested ...

  1. Analysis of Complement C3 Gene Reveals Susceptibility to Severe Preeclampsia

    A. Inkeri Lokki

    2017-05-01

    Full Text Available Preeclampsia (PE is a common vascular disease of pregnancy with genetic predisposition. Dysregulation of the complement system has been implicated, but molecular mechanisms are incompletely understood. In this study, we determined the potential linkage of severe PE to the most central complement gene, C3. Three cohorts of Finnish patients and controls were recruited for a genetic case-control study. Participants were genotyped using Sequenom genotyping and Sanger sequencing. Initially, we studied 259 Finnish patients with severe PE and 426 controls from the Southern Finland PE and the Finnish population-based PE cohorts. We used a custom-made single nucleotide polymorphism (SNP genotyping assay consisting of 98 SNPs in 18 genes that encode components of the complement system. Following the primary screening, C3 was selected as the candidate gene and consequently Sanger sequenced. Fourteen SNPs from C3 were also genotyped by a Sequenom panel in 960 patients with severe PE and 705 controls, including already sequenced individuals. Three of the 43 SNPs observed within C3 were associated with severe PE: rs2287845 (p = 0.038, OR = 1.158, rs366510 (p = 0.039, OR = 1.158, and rs2287848 (p = 0.041, OR = 1.155. We also discovered 16 SNP haplotypes with extreme linkage disequilibrium in the middle of the gene with a protective (p = 0.044, OR = 0.628 or a predisposing (p = 0.011, OR = 2.110 effect to severe PE depending on the allele combination. Genetic variants associated with PE are located in key domains of C3 and could thereby influence the function of C3. This is, as far as we are aware, the first candidate gene in the complement system with an association to a clinically relevant PE subphenotype, severe PE. The result highlights a potential role for the complement system in the pathogenesis of PE and may help in defining prognostic and therapeutic subgroups of preeclamptic women.

  2. Automatic scatter detection in fluorescence landscapes by means of spherical principal component analysis

    Kotwa, Ewelina Katarzyna; Jørgensen, Bo Munk; Brockhoff, Per B.

    2013-01-01

    In this paper, we introduce a new method, based on spherical principal component analysis (S‐PCA), for the identification of Rayleigh and Raman scatters in fluorescence excitation–emission data. These scatters should be found and eliminated as a prestep before fitting parallel factor analysis...... models to the data, in order to avoid model degeneracies. The work is inspired and based on a previous research, where scatter removal was automatic (based on a robust version of PCA called ROBPCA) and required no visual data inspection but appeared to be computationally intensive. To overcome...... this drawback, we implement the fast S‐PCA in the scatter identification routine. Moreover, an additional pattern interpolation step that complements the method, based on robust regression, will be applied. In this way, substantial time savings are gained, and the user's engagement is restricted to a minimum...

  3. CHLOROPHYLL a FLUORESCENCE ANALYSIS IN FORESTS

    M. Pollastrini

    2016-03-01

    Full Text Available A European-wide assessment of chlorophyll a fluorescence (ChlF, prompt fluorescence on dark-adapted samples parameters in forest ecosystems was carried out in the years 2012-2013, within the 7FP FunDivEUROPE project. A total of 1596 trees growing in 209 stands distributed in six countries, from Mediterranean to boreal sites, were sampled. This paper shows the applicability of the ChlF in forest ecology surveys, the protocols adopted for leaf sampling and ChlF measurements, the variability of the ChlF parameters within and between trees, their dependence to environmental factors and the relationships with other functional leaf traits. The most relevant findings were as follows: (i The least variable ChlF parameter within and between the trees was the maximum quantum yield of primary photochemistry (FV/FM, whereas the performance indices (PIABS and PITOT showed the highest variability; (ii for a given tree, the ChlF parameters measured at two heights of the crown (top and bottom leaves were correlated and, in coniferous species, the ChlF parameters were correlated between different needle age classes (from the current year and previous year; (iii the ChlF parameters showed a geographical pattern, and the photochemical performance of the forest trees was higher in central Europe than in the edge sites (northernmost and southernmost; and (iv ChlF parameters showed different sensitivity to specific environmental factors: FV/FM increased with the increase of the leaf area index of stands and soil fertility; ΔVIP was reduced under high temperature and drought. The photochemical responses of forest tree species, analyzed with ChlF parameters, were influenced by the ecology of the trees (i.e. their functional groups, continental distribution, successional status, etc., tree species’ richness and composition of the stands. Our results support the applicability and usefulness of the ChlF in forest monitoring investigations on a large spatial scale and

  4. Application of X-ray fluorescence analysis in environmental research

    Kliment, V.; Kliman, J.; Turzo, I.

    1978-01-01

    A description is presented of the X-ray fluorescence analysis principles and of its possibilities in the study of environmental pollution impact. Experiments with X-ray fluorescence analysis using 241-Am and a Ge(Li) semiconductor detector are discussed. The reproducibility of determinations in dependence on the sample preparation and the evaluation of peak surfaces of characteristic radiation is shown. The dependence of the peak surface on the elemental contents in the sample was linear. Detection limits of the investigated elements ranged in tenths of μg for 300 s measurement. (author)

  5. 3-D Image Analysis of Fluorescent Drug Binding

    M. Raquel Miquel

    2005-01-01

    Full Text Available Fluorescent ligands provide the means of studying receptors in whole tissues using confocal laser scanning microscopy and have advantages over antibody- or non-fluorescence-based method. Confocal microscopy provides large volumes of images to be measured. Histogram analysis of 3-D image volumes is proposed as a method of graphically displaying large amounts of volumetric image data to be quickly analyzed and compared. The fluorescent ligand BODIPY FL-prazosin (QAPB was used in mouse aorta. Histogram analysis reports the amount of ligand-receptor binding under different conditions and the technique is sensitive enough to detect changes in receptor availability after antagonist incubation or genetic manipulations. QAPB binding was concentration dependent, causing concentration-related rightward shifts in the histogram. In the presence of 10 μM phenoxybenzamine (blocking agent, the QAPB (50 nM histogram overlaps the autofluorescence curve. The histogram obtained for the 1D knockout aorta lay to the left of that of control and 1B knockout aorta, indicating a reduction in 1D receptors. We have shown, for the first time, that it is possible to graphically display binding of a fluorescent drug to a biological tissue. Although our application is specific to adrenergic receptors, the general method could be applied to any volumetric, fluorescence-image-based assay.

  6. X-ray fluorescence spectrometry applied to soil analysis

    Salvador, Vera Lucia Ribeiro; Sato, Ivone Mulako; Scapin Junior, Wilson Santo; Scapin, Marcos Antonio; Imakima, Kengo

    1997-01-01

    This paper studies the X-ray fluorescence spectrometry applied to the soil analysis. A comparative study of the WD-XRFS and ED-XRFS techniques was carried out by using the following soil samples: SL-1, SOIL-7 and marine sediment SD-M-2/TM, from IAEA, and clay, JG-1a from Geological Survey of Japan (GSJ)

  7. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, Jan; Koleska, M.; Voljanskij, A.

    2015-01-01

    Roč. 116, NOV (2015), s. 56-59 ISSN 0969-806X R&D Projects: GA TA ČR TA01010237; GA MŠk LM2011019 Institutional support: RVO:61389005 Keywords : fluorescent lamp * mercury measurement * neutron activation analysis * research reactor Subject RIV: BG - Nuclear , Atomic and Molecular Physics, Colliders Impact factor: 1.207, year: 2015

  8. A portable tube exciting X-ray fluorescence analysis system

    Yang Qiang; Lai Wanchang; Ge Liangquan

    2009-01-01

    Article introduced a portable tube exciting X-ray fluorescence analysis system which is based on arm architecture. Also, we designed Tube control circuit and finished preliminary application. The energy and the intensity of the photon can be adjusted continuously by using the tube. Experiments show that high excitation efficiency obtained by setting the appropriate parameters of the tube for the various elements. (authors)

  9. Multielement methods of atomic fluorescence analysis of enviromental samples

    Rigin, V.I.

    1985-01-01

    A multielement method of atomic fluorescence analysis of environmental samples based on sample decomposition by autoclave fluorination and gas-phase atomization of volatile compounds in inductive araon plasma using a nondispersive polychromator is suggested. Detection limits of some elements (Be, Sr, Cd, V, Mo, Te, Ru etc.) for different sample forms introduced in to an analyzer are given

  10. Quantitative x-ray fluorescent analysis using fundamental parameters

    Sparks, C.J. Jr.

    1976-01-01

    A monochromatic source of x-rays for sample excitation permits the use of pure elemental standards and relatively simple calculations to convert the measured fluorescent intensities to an absolute basis of weight per unit weight of sample. Only the mass absorption coefficients of the sample for the exciting and the fluorescent radiation need be determined. Besides the direct measurement of these absorption coefficients in the sample, other techniques are considered which require fewer sample manipulations and measurements. These fundamental parameters methods permit quantitative analysis without recourse to the time-consuming process of preparing nearly identical standards

  11. Quantitative analysis with energy dispersive X-ray fluorescence analyser

    Kataria, S.K.; Kapoor, S.S.; Lal, M.; Rao, B.V.N.

    1977-01-01

    Quantitative analysis of samples using radioisotope excited energy dispersive x-ray fluorescence system is described. The complete set-up is built around a locally made Si(Li) detector x-ray spectrometer with an energy resolution of 220 eV at 5.94 KeV. The photopeaks observed in the x-ray fluorescence spectra are fitted with a Gaussian function and the intensities of the characteristic x-ray lines are extracted, which in turn are used for calculating the elemental concentrations. The results for a few typical cases are presented. (author)

  12. Molecular and expression analysis of complement component C5 in the nurse shark (Ginglymostoma cirratum) and its predicted functional role.

    Graham, Matthew; Shin, Dong-Ho; Smith, Sylvia L

    2009-07-01

    We present the complete cDNA sequence of shark (Ginglymostoma cirratum) pro-C5 and its molecular characterization with a descriptive analysis of the structural elements necessary for its potential functional role as a potent mediator of inflammation (fragment C5a) and initiator molecule (fragment C5b) for the assembly of the membrane attack complex (MAC) upon activation by C5 convertase. In mammals the three complement activation cascades, the classical, alternative and lectin pathways, converge at the activation of C3, a pivotal complement protein. It is, however, the subsequent activation of the next complement component, C5, which is the focal point at which the initiation of the terminal lytic pathway takes place and involves the stepwise assembly of the MAC. The effector cytolytic function of complement occurs with the insertion of MAC into target membranes causing dough-nut like holes and cell leakage. The lytic activity of shark complement results in structurally similar holes in target membranes suggesting the assembly of a shark MAC that likely involves a functional analogue of C5. The composition of shark MAC remains unresolved and to date conclusive evidence has been lacking for shark C5. The gene has not been cloned nor has the serum protein been characterized for any elasmobranch species. This report is the first to confirm the presence of C5 homologue in the shark. GcC5 is remarkably similar to human C5 in overall structure and domain arrangement. The GcC5 cDNA measured 5160-bp with 5' and 3' UTRs of 35 bp and 79 bp, respectively. Structural analysis of the derived protein sequence predicts a molecule that is a two-chain structure which lacks a thiolester bond and contains a C5 convertase cleavage site indicating that activation will generate two peptides, akin to C5b and C5a. The putative GcC5 molecule also contains the C-terminal C345C/Netrin module that characterizes C3, C4 and C5. Multiple alignment of deduced amino acid sequences shows that GcC5

  13. Mercury mass measurement in fluorescent lamps via neutron activation analysis

    Viererbl, L.; Vinš, M.; Lahodová, Z.; Fuksa, A.; Kučera, J.; Koleška, M.; Voljanskij, A.

    2015-11-01

    Mercury is an essential component of fluorescent lamps. Not all fluorescent lamps are recycled, resulting in contamination of the environment with toxic mercury, making measurement of the mercury mass used in fluorescent lamps important. Mercury mass measurement of lamps via instrumental neutron activation analysis (NAA) was tested under various conditions in the LVR-15 research reactor. Fluorescent lamps were irradiated in different positions in vertical irradiation channels and a horizontal channel in neutron fields with total fluence rates from 3×108 cm-2 s-1 to 1014 cm-2 s-1. The 202Hg(n,γ)203Hg nuclear reaction was used for mercury mass evaluation. Activities of 203Hg and others induced radionuclides were measured via gamma spectrometry with an HPGe detector at various times after irradiation. Standards containing an Hg2Cl2 compound were used to determine mercury mass. Problems arise from the presence of elements with a large effective cross section in luminescent material (europium, antimony and gadolinium) and glass (boron). The paper describes optimization of the NAA procedure in the LVR-15 research reactor with particular attention to influence of neutron self-absorption in fluorescent lamps.

  14. Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis

    Lee, Jae Eun; Lee, Jae Young; Kim, Hong Rye; Shin, Hyun Young; Lin, Tao; Jin, Dong Il

    2015-01-01

    Two dimensional-fluorescence difference gel electrophoresis (2D DIGE) is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2 non-pregnant were used in this study. The pre-electrophoretic labeling of pregnant and non-pregnant serum proteins were mixed with Cy3 and Cy5 fluorescent dyes, respectively, and an internal standard was labeled with Cy2. Labeled proteins with Cy2, Cy3, and Cy5 were separated together in a single gel, and then were detected by fluorescence image analyzer. The 2D DIGE method using fluorescence CyDye DIGE flour had higher sensitivity than conventional 2D gel electrophoresis, and showed reproducible results. Approximately 1,500 protein spots were detected by 2D DIGE. Several proteins showed a more than 1.5-fold up and down regulation between non-pregnant and pregnant serum proteins. The differentially expressed proteins were identified by MALDI-TOF mass spectrometer. A total 16 protein spots were detected to regulate differentially in the pregnant serum, among which 7 spots were up-regulated proteins such as conglutinin precursor, modified bovine fibrinogen and IgG1, and 6 spots were down-regulated proteins such as hemoglobin, complement component 3, bovine fibrinogen and IgG2a three spots were not identified. The identified proteins demonstrate that early pregnant bovine serum may have several pregnancy-specific proteins, and these could be a valuable information for the development of pregnancy-diagnostic markers in early pregnancy bovine serum. PMID:25925056

  15. Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis

    Jae Eun Lee

    2015-06-01

    Full Text Available Two dimensional-fluorescence difference gel electrophoresis (2D DIGE is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2 non-pregnant were used in this study. The pre-electrophoretic labeling of pregnant and non-pregnant serum proteins were mixed with Cy3 and Cy5 fluorescent dyes, respectively, and an internal standard was labeled with Cy2. Labeled proteins with Cy2, Cy3, and Cy5 were separated together in a single gel, and then were detected by fluorescence image analyzer. The 2D DIGE method using fluorescence CyDye DIGE flour had higher sensitivity than conventional 2D gel electrophoresis, and showed reproducible results. Approximately 1,500 protein spots were detected by 2D DIGE. Several proteins showed a more than 1.5-fold up and down regulation between non-pregnant and pregnant serum proteins. The differentially expressed proteins were identified by MALDI-TOF mass spectrometer. A total 16 protein spots were detected to regulate differentially in the pregnant serum, among which 7 spots were up-regulated proteins such as conglutinin precursor, modified bovine fibrinogen and IgG1, and 6 spots were down-regulated proteins such as hemoglobin, complement component 3, bovine fibrinogen and IgG2a three spots were not identified. The identified proteins demonstrate that early pregnant bovine serum may have several pregnancy-specific proteins, and these could be a valuable information for the development of pregnancy-diagnostic markers in early pregnancy bovine serum.

  16. [Analysis of fluorescence spectrum of petroleum-polluted water].

    Huang, Miao-Fen; Song, Qing-Jun; Xing, Xu-Feng; Jian, Wei-Jun; Liu, Yuan; Zhao, Zu-Long

    2014-09-01

    In four ratio experiments, natural waters, sampled from the mountain reservoir and the sea water around Dalian city, were mixed with the sewage from petroleum refinery and petroleum exploitation plants. The fluorescence spectra of water samples containing only chromophoric dissolved organic matters(CDOM), samples containing only petroleum, and samples containing a mixture of petroleum and CDOM were analyzed, respectively. The purpose of this analysis is to provide a basis for determining the contribution of petroleum substances and CDOM to the total absorption coefficient of the petroleum-contaminated water by using fluorescence technique. The results showed that firstly, CDOM in seawater had three main fluorescence peaks at Ex: 225-230 nm/Em: 320-330 nm, Ex: 280 nm/Em: 340 nm and Ex: 225-240 nm/Em: 430-470 nm, respectively, and these may arise from the oceanic chlorophyll. CDOM in natural reservoir water had two main fluorescence peaks at EX: 240- 260 nm/Em: 420-450 nm and Ex: 310~350 nm/Em: 420--440 nm, respectively, and these may arise from the terrestrial sources; secondly, the water samples containing only petroleum extracted with n-hexane had one to three fluorescence spectral peaksat Ex: 220-240 nm/Em: 320-340 nm, Ex: 270-290 nm/Em: 310-340 nm and Ex: 220-235 nm/Em: 280-310 nm, respectively, caused by their hydrocarbon component; finally, the water samples containing both petroleum and CDOM showed a very strong fluorescence peak at Ex: 230-250 nm/Em: 320-370 nm, caused by the combined effect of CDOM and petroleum hydrocarbons.

  17. Analysis of hyperspectral fluorescence images for poultry skin tumor inspection

    Kong, Seong G.; Chen, Yud-Ren; Kim, Intaek; Kim, Moon S.

    2004-02-01

    We present a hyperspectral fluorescence imaging system with a fuzzy inference scheme for detecting skin tumors on poultry carcasses. Hyperspectral images reveal spatial and spectral information useful for finding pathological lesions or contaminants on agricultural products. Skin tumors are not obvious because the visual signature appears as a shape distortion rather than a discoloration. Fluorescence imaging allows the visualization of poultry skin tumors more easily than reflectance. The hyperspectral image samples obtained for this poultry tumor inspection contain 65 spectral bands of fluorescence in the visible region of the spectrum at wavelengths ranging from 425 to 711 nm. The large amount of hyperspectral image data is compressed by use of a discrete wavelet transform in the spatial domain. Principal-component analysis provides an effective compressed representation of the spectral signal of each pixel in the spectral domain. A small number of significant features are extracted from two major spectral peaks of relative fluorescence intensity that have been identified as meaningful spectral bands for detecting tumors. A fuzzy inference scheme that uses a small number of fuzzy rules and Gaussian membership functions successfully detects skin tumors on poultry carcasses. Spatial-filtering techniques are used to significantly reduce false positives.

  18. Automating X-ray Fluorescence Analysis for Rapid Astrobiology Surveys.

    Thompson, David R; Flannery, David T; Lanka, Ravi; Allwood, Abigail C; Bue, Brian D; Clark, Benton C; Elam, W Timothy; Estlin, Tara A; Hodyss, Robert P; Hurowitz, Joel A; Liu, Yang; Wade, Lawrence A

    2015-11-01

    A new generation of planetary rover instruments, such as PIXL (Planetary Instrument for X-ray Lithochemistry) and SHERLOC (Scanning Habitable Environments with Raman Luminescence for Organics and Chemicals) selected for the Mars 2020 mission rover payload, aim to map mineralogical and elemental composition in situ at microscopic scales. These instruments will produce large spectral cubes with thousands of channels acquired over thousands of spatial locations, a large potential science yield limited mainly by the time required to acquire a measurement after placement. A secondary bottleneck also faces mission planners after downlink; analysts must interpret the complex data products quickly to inform tactical planning for the next command cycle. This study demonstrates operational approaches to overcome these bottlenecks by specialized early-stage science data processing. Onboard, simple real-time systems can perform a basic compositional assessment, recognizing specific features of interest and optimizing sensor integration time to characterize anomalies. On the ground, statistically motivated visualization can make raw uncalibrated data products more interpretable for tactical decision making. Techniques such as manifold dimensionality reduction can help operators comprehend large databases at a glance, identifying trends and anomalies in data. These onboard and ground-side analyses can complement a quantitative interpretation. We evaluate system performance for the case study of PIXL, an X-ray fluorescence spectrometer. Experiments on three representative samples demonstrate improved methods for onboard and ground-side automation and illustrate new astrobiological science capabilities unavailable in previous planetary instruments. Dimensionality reduction-Planetary science-Visualization.

  19. Analysis of fluorescently labeled glycosphingolipid-derived oligosaccharides following ceramide glycanase digestion and anthranilic acid labeling.

    Neville, David C A; Coquard, Virginie; Priestman, David A; te Vruchte, Danielle J M; Sillence, Daniel J; Dwek, Raymond A; Platt, Frances M; Butters, Terry D

    2004-08-15

    Interest in cellular glycosphingolipid (GSL) function has necessitated the development of a rapid and sensitive method to both analyze and characterize the full complement of structures present in various cells and tissues. An optimized method to characterize oligosaccharides released from glycosphingolipids following ceramide glycanase digestion has been developed. The procedure uses the fluorescent compound anthranilic acid (2-aminobenzoic acid; 2-AA) to label oligosaccharides prior to analysis using normal-phase high-performance liquid chromatography. The labeling procedure is rapid, selective, and easy to perform and is based on the published method of Anumula and Dhume [Glycobiology 8 (1998) 685], originally used to analyze N-linked oligosaccharides. It is less time consuming than a previously published 2-aminobenzamide labeling method [Anal. Biochem. 298 (2001) 207] for analyzing GSL-derived oligosaccharides, as the fluorescent labeling is performed on the enzyme reaction mixture. The purification of 2-AA-labeled products has been improved to ensure recovery of oligosaccharides containing one to four monosaccharide units, which was not previously possible using the Anumula and Dhume post-derivatization purification procedure. This new approach may also be used to analyze both N- and O-linked oligosaccharides.

  20. Complementing the Numbers: A Text Mining Analysis of College Course Withdrawals

    Michalski, Greg V.

    2011-01-01

    Excessive college course withdrawals are costly to the student and the institution in terms of time to degree completion, available classroom space, and other resources. Although generally well quantified, detailed analysis of the reasons given by students for course withdrawal is less common. To address this, a text mining analysis was performed…

  1. The lipid dependence of melittin action investigated by dual-color fluorescence burst analysis

    Bogaart, Geert van den; Mika, Jacek T.; Krasnikov, Viktor; Poolman, Bert

    Dual-color fluorescence-burst analysis was used to study melittin-induced leakage of macromolecules from liposomes of various lipid compositions. To perform dual-color fluorescence-burst analysis, fluorescently labeled size-marker molecules were encapsulated into liposomes, labeled with a second

  2. Fluorescent foci quantitation for high-throughput analysis

    Elena Ledesma-Fernández

    2015-06-01

    Full Text Available A number of cellular proteins localize to discrete foci within cells, for example DNA repair proteins, microtubule organizing centers, P bodies or kinetochores. It is often possible to measure the fluorescence emission from tagged proteins within these foci as a surrogate for the concentration of that specific protein. We wished to develop tools that would allow quantitation of fluorescence foci intensities in high-throughput studies. As proof of principle we have examined the kinetochore, a large multi-subunit complex that is critical for the accurate segregation of chromosomes during cell division. Kinetochore perturbations lead to aneuploidy, which is a hallmark of cancer cells. Hence, understanding kinetochore homeostasis and regulation are important for a global understanding of cell division and genome integrity. The 16 budding yeast kinetochores colocalize within the nucleus to form a single focus. Here we have created a set of freely-available tools to allow high-throughput quantitation of kinetochore foci fluorescence. We use this ‘FociQuant’ tool to compare methods of kinetochore quantitation and we show proof of principle that FociQuant can be used to identify changes in kinetochore protein levels in a mutant that affects kinetochore function. This analysis can be applied to any protein that forms discrete foci in cells.

  3. How Can Big Data Complement Expert Analysis? A Value Chain Case Study

    Kyungtae Kim

    2018-03-01

    Full Text Available In the world of big data, there is a need to investigate how data-driven approaches can support expert-based analyses during a technology planning process. To meet this goal, we examined opportunities and challenges for big data analytics in the social sciences, particularly with respect to value chain analysis. To accomplish this, we designed a value chain mapping experiment that aimed to compare the results of expert-based and data-based mappings. In the expert-based approach, we asked an industry expert to visually depict an industry value chain based on insights and collected data. We also reviewed a previously published value chain developed by a panel of industry experts during a national technology planning process. In the data-driven analysis, we used a massive number of business transaction records between companies under the assumption that the data would be useful in identifying relationships between items in a value chain. The case study results demonstrated that data-driven analysis can help researchers understand the current status of industry structures, enabling them to develop more realistic, although less flexible value chain maps. This approach is expected to provide more value when used in combination with other databases. It is important to note that significant effort is required to develop an elaborate analysis algorithm, and data preprocessing is essential for obtaining meaningful results, both of which make this approach challenging. Experts’ insights are still helpful for validating the analytic results in value chain mapping.

  4. Ultratrace analysis of transuranic actinides by laser-induced fluorescence

    Miller, S.M.

    1983-10-31

    Ultratrace quantities of transuranic actinides are detected indirectly by their effect on the fluorescent emissions of a preselected fluorescent species. Transuranic actinides in a sample are coprecipitated with a host lattice material containing at least one preselected fluorescent species. The actinide either quenches or enhances the laser-induced fluorescence of the preselected fluorescent species. The degree of enhancement or quenching is quantitatively related to the concentration of actinide in the sample.

  5. Handbook of practical X-ray fluorescence analysis

    Beckhoff, B.; Wedell, R.; Wolff, H.

    2006-01-01

    X-ray fluorescence analysis (XRF) is a reliable multi-elemental and nondestructive analytical method widely used in research and industrial applications. This practical handbook provides self-contained modules featuring XRF instrumentation, quantification methods, and most of the current applications. The broad spectrum of topics is due to the efforts of a large number of authors from a variety of different types of institutions such as universities, research institutes, and companies. The book gives a survey of the theoretical fundamentals, analytical instrumentation, software for data processing, various excitation regimes including gracing incidents and microfocus measurements, quantitative analysis, applications in routine and micro analysis, mineralogy, biology, medicine, criminal investigations, archeology, metallurgy, abrasion, microelectronics, environmental air and water analysis. It gives the basic knowledge on this technique, information on analytical equipment and guides the reader to the various applications. This practical handbook is intended as a resource for graduate students, research scientists, and industrial users. (orig.)

  6. Handbook of practical X-ray fluorescence analysis

    Beckhoff, B. [Physikalisch-Technische Bundesanstalt, Berlin (Germany). X-ray Spectrometry; Kanngiesser, B. [Technische Univ. Berlin (Germany). Inst. fuer Atomare Physik und Fachdidaktik; Langhoff, N. [IfG-Institute for Scientific Instruments GmbH, Berlin (Germany); Wedell, R.; Wolff, H. (eds.) [Institut fuer Angewandte Photonik e.V., Berlin (Germany)

    2006-07-01

    X-ray fluorescence analysis (XRF) is a reliable multi-elemental and nondestructive analytical method widely used in research and industrial applications. This practical handbook provides self-contained modules featuring XRF instrumentation, quantification methods, and most of the current applications. The broad spectrum of topics is due to the efforts of a large number of authors from a variety of different types of institutions such as universities, research institutes, and companies. The book gives a survey of the theoretical fundamentals, analytical instrumentation, software for data processing, various excitation regimes including gracing incidents and microfocus measurements, quantitative analysis, applications in routine and micro analysis, mineralogy, biology, medicine, criminal investigations, archeology, metallurgy, abrasion, microelectronics, environmental air and water analysis. It gives the basic knowledge on this technique, information on analytical equipment and guides the reader to the various applications. This practical handbook is intended as a resource for graduate students, research scientists, and industrial users. (orig.)

  7. X-ray fluorescence analysis of welding fume particles

    Carsey, T.P.

    1982-01-01

    A commercial standard filter set and two laboratory-made standard filter sets are compared via the analysis of generated welding fume samples by X-ray fluorescence. The latter standards are made by (1) hydrophobic-edge membrane filters spiked with prepared metal ion solutions, and (2) filters through which a dispersion of metal oxide powder in isopropanol has been drawn. The results are presented in table form. Precision (Pre) is the relative standard deviation of the six samples. Four main conclusions are enumerated

  8. Quantification procedures in micro X-ray fluorescence analysis

    Kanngiesser, Birgit

    2003-01-01

    For the quantification in micro X-ray fluorescence analysis standardfree quantification procedures have become especially important. An introduction to the basic concepts of these quantification procedures is given, followed by a short survey of the procedures which are available now and what kind of experimental situations and analytical problems are addressed. The last point is extended by the description of an own development for the fundamental parameter method, which renders the inclusion of nonparallel beam geometries possible. Finally, open problems for the quantification procedures are discussed

  9. Analysis of the complement and molecular evolution of tRNA genes in cow

    Barris Wesley C

    2009-04-01

    Full Text Available Abstract Background Detailed information regarding the number and organization of transfer RNA (tRNA genes at the genome level is becoming readily available with the increase of DNA sequencing of whole genomes. However the identification of functional tRNA genes is challenging for species that have large numbers of repetitive elements containing tRNA derived sequences, such as Bos taurus. Reliable identification and annotation of entire sets of tRNA genes allows the evolution of tRNA genes to be understood on a genomic scale. Results In this study, we explored the B. taurus genome using bioinformatics and comparative genomics approaches to catalogue and analyze cow tRNA genes. The initial analysis of the cow genome using tRNAscan-SE identified 31,868 putative tRNA genes and 189,183 pseudogenes, where 28,830 of the 31,868 predicted tRNA genes were classified as repetitive elements by the RepeatMasker program. We then used comparative genomics to further discriminate between functional tRNA genes and tRNA-derived sequences for the remaining set of 3,038 putative tRNA genes. For our analysis, we used the human, chimpanzee, mouse, rat, horse, dog, chicken and fugu genomes to predict that the number of active tRNA genes in cow lies in the vicinity of 439. Of this set, 150 tRNA genes were 100% identical in their sequences across all nine vertebrate genomes studied. Using clustering analyses, we identified a new tRNA-GlyCCC subfamily present in all analyzed mammalian genomes. We suggest that this subfamily originated from an ancestral tRNA-GlyGCC gene via a point mutation prior to the radiation of the mammalian lineages. Lastly, in a separate analysis we created phylogenetic profiles for each putative cow tRNA gene using a representative set of genomes to gain an overview of common evolutionary histories of tRNA genes. Conclusion The use of a combination of bioinformatics and comparative genomics approaches has allowed the confident identification of a

  10. Hydrologically complemented deterministic slope stability analysis in part of Indian Lesser Himalaya

    John Mathew

    2016-09-01

    Full Text Available This study uses a deterministic approach to evaluate the factor of safety (FS of the terrain for different hydrological conditions, in part of Indian Lesser Himalaya. The results indicate sudden increase in the percentage unstable area from 7.5% to 13.8% for rainfall intensity variation from 50 to 100 mm/day. For the rainfall intensity of 15 August 2007 which caused many landslides in the study area, 18.5% of the total area was unstable and it increases to 21.7%, 23.5% and 24.7%, respectively, for rainfall intensities corresponding to 10, 25 and 50 year return periods. This increment stagnates at about 260 mm/day, making about 25% of the area unstable. Higher rainfall intensities make progressively gentler slopes unstable, but limited to 25 degrees of slope in this area. The area underlain by granitic gneiss showed 23.1% of area as unstable for 135 mm/day of rainfall intensity, and was followed by those areas underlain by amphibolite (16%, limestone (13.7% and quartzite (10.4%. Receiver operating characteristic (ROC curve analysis has given 84.2% accuracy for the model. Conversion of FS to failure probability through Z scores enables identification unstable or marginally unstable areas, for planning selective slope stabilization measures.

  11. Isolation and sequence analysis of a cDNA clone encoding the fifth complement component

    Lundwall, Åke B; Wetsel, Rick A; Kristensen, Torsten

    1985-01-01

    DNA clone of 1.85 kilobase pairs was isolated. Hybridization of the mixed-sequence probe to the complementary strand of the plasmid insert and sequence analysis by the dideoxy method predicted the expected protein sequence of C5a (positions 1-12), amino-terminal to the anticipated priming site. The sequence......, subcloned into M13 mp8, and sequenced at random by the dideoxy technique, thereby generating a contiguous sequence of 1703 base pairs. This clone contained coding sequence for the C-terminal 262 amino acid residues of the beta-chain, the entire C5a fragment, and the N-terminal 98 residues of the alpha......'-chain. The 3' end of the clone had a polyadenylated tail preceded by a polyadenylation recognition site, a 3'-untranslated region, and base pairs homologous to the human Alu concensus sequence. Comparison of the derived partial human C5 protein sequence with that previously determined for murine C3 and human...

  12. Quantitative analysis by computer controlled X-ray fluorescence spectrometer

    Balasubramanian, T.V.; Angelo, P.C.

    1981-01-01

    X-ray fluorescence spectroscopy has become a widely accepted method in the metallurgical field for analysis of both minor and major elements. As encountered in many other analytical techniques, the problem of matrix effect generally known as the interelemental effects is to be dealt with effectively in order to make the analysis accurate. There are several methods by which the effects of matrix on the analyte are minimised or corrected for and the mathematical correction is one among them. In this method the characteristic secondary X-ray intensities are measured from standard samples and correction coefficients. If any, for interelemental effects are evaluated by mathematical calculations. This paper describes attempts to evaluate the correction coefficients for interelemental effects by multiple linear regression programmes using a computer for the quantitative analysis of stainless steel and a nickel base cast alloy. The quantitative results obtained using this method for a standard stainless steel sample are compared with the given certified values. (author)

  13. X-ray Microprobe for Fluorescence and Diffraction Analysis

    Ice, G.E.

    2005-01-01

    X-ray diffraction (see unit 1.1) and x-ray excited fluorescence analysis are powerful techniques for the nondestructive measurement of crystal structure and chemical composition. X-ray fluorescence analysis is inherently nondestructive with orders of magnitude lower power deposited for the same detectable limit as with fluorescence excited by charged particle probes (Sparks, 1980). X-ray diffraction analysis is sensitive to crystal structure with orders-of-magnitude greater sensitivity to crystallographic strain than electron probes (Rebonato, et al. 1989). When a small-area x-ray microbeam is used as the probe, chemical composition (Z>14), crystal structure, crystalline texture, and crystalline strain distributions can be determined. These distributions can be studied both at the surface of the sample and deep within the sample (Fig. 1). Current state-of-the-art can achieve an ∼1 mm-D x-ray microprobe and an ∼0.1 mm-D x-ray microprobe has been demonstrated (Bilderback, et al., 1994). Despite their great chemical and crystallographic sensitivities, x-ray microprobe techniques have until recently been restricted by inefficient x-ray focusing optics and weak x-ray sources; x-ray microbeam analysis was largely superseded by electron techniques in the 50's. However, interest in x-ray microprobe techniques has now been revived (Howells, et al., 1983; Ice and Sparks, 1984; Chevallier, et al., 1997; Riekel 1992; Thompson, el al., 1992; and Making and Using... 1997) by the development of efficient x-ray focusing optics and ultra-high intensity synchrotron x-ray sources (Buras and Tazzari, 1984; Shenoy, et al., 1988). These advances have increased the achievable microbeam flux by more than 11 orders of magnitude (Fig. 2) (Ice, 1997); the flux in a tunable 1 mm-D beam on a 'so called' 3rd-generation synchrotron source such as the APS can exceed the flux in a fixed-energy mm2 beam on a conventional source. These advances make x-ray microfluorescence and x

  14. Identification and functional analysis of cytochrome P450 complement in Streptomyces virginiae IBL14

    2013-01-01

    Background As well known, both natural and synthetic steroidal compounds are powerful endocrine disrupting compounds (EDCs) which can cause reproductive toxicity and affect cellular development in mammals and thus are generally regarded as serious contributors to water pollution. Streptomyces virginiae IBL14 is an effective degradative strain for many steroidal compounds and can also catalyze the C25 hydroxylation of diosgenin, the first-ever biotransformation found on the F-ring of diosgenin. Results To completely elucidate the hydroxylation function of cytochrome P450 genes (CYPs) found during biotransformation of steroids by S. virginiae IBL14, the whole genome sequencing of this strain was carried out via 454 Sequencing Systems. The analytical results of BLASTP showed that the strain IBL14 contains 33 CYPs, 7 ferredoxins and 3 ferredoxin reductases in its 8.0 Mb linear chromosome. CYPs from S. virginiae IBL14 are phylogenetically closed to those of Streptomyces sp. Mg1 and Streptomyces sp. C. One new subfamily was found as per the fact that the CYP Svu001 in S. virginiae IBL14 shares 66% identity only to that (ZP_05001937, protein identifer) from Streptomyces sp. Mg1. Further analysis showed that among all of the 33 CYPs in S. virginiae IBL14, three CYPs are clustered with ferredoxins, one with ferredoxin and ferredoxin reductase and three CYPs with ATP/GTP binding proteins, four CYPs arranged with transcriptional regulatory genes and one CYP located on the upstream of an ATP-binding protein and transcriptional regulators as well as four CYPs associated with other functional genes involved in secondary metabolism and degradation. Conclusions These characteristics found in CYPs from S. virginiae IBL14 show that the EXXR motif in the K-helix is not absolutely conserved in CYP157 family and I-helix not absolutely essential for the CYP structure, too. Experimental results showed that both CYP Svh01 and CYP Svu022 are two hydroxylases, capable of bioconverting

  15. Absorption correction factor in X-ray fluorescent quantitative analysis

    Pimjun, S.

    1994-01-01

    An experiment on absorption correction factor in X-ray fluorescent quantitative analysis were carried out. Standard samples were prepared from the mixture of Fe 2 O 3 and tapioca flour at various concentration of Fe 2 O 3 ranging from 5% to 25%. Unknown samples were kaolin containing 3.5% to-50% of Fe 2 O 3 Kaolin samples were diluted with tapioca flour in order to reduce the absorption of FeK α and make them easy to prepare. Pressed samples with 0.150 /cm 2 and 2.76 cm in diameter, were used in the experiment. Absorption correction factor is related to total mass absorption coefficient (χ) which varied with sample composition. In known sample, χ can be calculated by conveniently the formula. However in unknown sample, χ can be determined by Emission-Transmission method. It was found that the relationship between corrected FeK α intensity and contents of Fe 2 O 3 in these samples was linear. This result indicate that this correction factor can be used to adjust the accuracy of X-ray intensity. Therefore, this correction factor is essential in quantitative analysis of elements comprising in any sample by X-ray fluorescent technique

  16. Molecular cloning, structural analysis and expression of complement component Bf/C2 genes in the nurse shark, Ginglymostoma cirratum.

    Shin, Dong-Ho; Webb, Barbara; Nakao, Miki; Smith, Sylvia L

    2007-01-01

    Factor B and C2 are serine proteases that provide the catalytic subunits of C3 and C5 convertases of the alternative (AP) and classical (CP) complement pathways. Two Bf/C2 cDNAs, GcBf/C2-1 and -2 (previously referred to as nsBf/C2-A and nsBf/C2-B), were isolated from the nurse shark, Ginglymostoma cirratum. GcBf/C2-1 and -2 are 3364 and 3082bp in length and encode a leader peptide, three CCPs, one VWFA, the serine protease domain and have a putative factor D/C1s/MASP cleavage site. Southern blots show that there might be up to two Bf/C2-like genes for each of the two GcBf/C2 isoforms. GcBf/C2-1 and -2 are constitutively expressed, albeit at different levels, in all nine tissues examined. Expression in erythrocytes is a novel finding. Structural analysis has revealed that the localization of glycosylation sites in the SP domain of both putative proteins indicates that the molecular organization of the shark molecules is more like C2 than factor B. Phylogenetic analysis indicates that GcBf/C2-1 and -2 and TrscBf of Triakis scyllia (another shark species) originated from a common ancestor and share a remote ancestor with Bf and C2 of mammals and bony fish.

  17. Preparation and Fluorescent Analysis of Plant Metaphase Chromosomes.

    Schwarzacher, Trude

    2016-01-01

    Good preparations are essential for informative analysis of both somatic and meiotic chromosomes, cytogenetics, and cell divisions. Fluorescent chromosome staining allows even small chromosomes to be visualized and counted, showing their morphology. Aneuploidies and polyploidies can be established for species, populations, or individuals while changes occurring in breeding lines during hybridization or tissue culture and transformation protocols can be assessed. The process of division can be followed during mitosis and meiosis including pairing and chiasma distribution, as well as DNA organization and structure during the evolution of chromosomes can be studied. This chapter presents protocols for pretreatment and fixation of material, including tips of how to grow plants to get good and healthy meristem with many divisions. The chromosome preparation technique is described using proteolytic enzymes, but acids can be used instead. Chromosome slide preparations are suitable for fluorochrome staining for fast screening (described in the chapter) or fluorescent in situ hybridization (see Schwarzacher and Heslop-Harrison, In situ hybridization. BIOS Scientific Publishers, Oxford, 2000).

  18. The use of fluorescent indoline dyes for side population analysis.

    Kohara, Hiroshi; Watanabe, Kohei; Shintou, Taichi; Nomoto, Tsuyoshi; Okano, Mie; Shirai, Tomoaki; Miyazaki, Takeshi; Tabata, Yasuhiko

    2013-01-01

    Dye efflux assay evaluated by flow cytometry is useful for stem cell studies. The side population (SP) cells, characterized by the capacity to efflux Hoechst 33342 dye, have been shown to be enriched for hematopoietic stem cells (HSCs) in bone marrow. In addition, SP cells are isolated from various tissues and cell lines, and are also potential candidates for cancer stem cells. However, ultra violet (UV) light, which is not common for every flow cytometer, is required to excite Hoechst 33342. Here we showed that a fluorescent indoline dye ZMB793 can be excited by 488-nm laser, equipped in almost all the modern flow cytometers, and ZMB793-excluding cells showed SP phenotype. HSCs were exclusively enriched in the ZMB793-excluding cells, while ZMB793 was localized in cytosol of bone marrow lineage cells. The efflux of ZMB793 dye was mediated by ATP binding cassette (ABC) transporter Abcg2. Moreover, staining properties were affected by the side-chain structure of the dyes. These data indicate that the fluorescent dye ZMB793 could be used for the SP cell analysis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Optimized elemental analysis of fluorescence lamp shredder waste.

    Hobohm, Julia; Kuchta, Kerstin; Krüger, Oliver; van Wasen, Sebastian; Adam, Christian

    2016-01-15

    Fluorescence lamps contain considerable amounts of rare earth elements (REE). Several recycling procedures for REE recovery from spent lamps have been established. However, despite their economic importance, the respective recycling is scarce so far, with an REE recovery rate of less than 1%. A reliable analysis of REE and other relevant metals like Yttrium is crucial for a thorough and complete recovery process. This applies both to the solid matter and aqueous phase, since most of the recycling processes include wet-chemical steps. We tested seven different reagent mixtures for microwave-assisted digestion of fluorescent lamp shredder, including hydrofluoric acid, perchloric acid, and hydrogen peroxide. We determined the concentrations of 25 of the most relevant rare earth and other trace elements (Al, P, Ti, V, Cr, Fe, Ni, Cu, Ga, Ge, As, Y, Ag, Cd, Sn, Sb, La, Ce, Eu, Gd, Tb, W, Au, Hg, and Pb) in the respective dilutions. Two independent digestions, one a mixture of perchlorid/nitric/hydrofluoric acid and the other aqua regia, showed the highest concentrations of 23 of these elements, excluding only Sn and Tb. The REE concentrations in the tested lamp shredder sample (stated in g/kg) were 10.2 (Y), 12.1 (La), 7.77 (Ce), 6.91 (Eu), 1.90 (Gd), and 4.11 (Tb). Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Genetic and Biochemical Analysis of Intragenic Complementation Events among Nitrate Reductase Apoenzyme-Deficient Mutants of Nicotiana Plumbaginifolia

    Pelsy, F.; Gonneau, M.

    1991-01-01

    Intragenic complementation has been observed between apoenzyme nitrate reductase-deficient mutants (nia) of Nicotiana plumbaginifolia. In vivo as in vitro, the NADH-nitrate reductase (NR) activity in plants heterozygous for two different nia alleles was lower than in the wild type plant, but the plants were able to grow on nitrate as a sole nitrogen source. NR activity, absent in extracts of homozygous nia mutants was restored by mixing extracts from two complementing nia mutants. These obser...

  1. Quantitative Brightness Analysis of Fluorescence Intensity Fluctuations in E. Coli.

    Kwang-Ho Hur

    Full Text Available The brightness measured by fluorescence fluctuation spectroscopy specifies the average stoichiometry of a labeled protein in a sample. Here we extended brightness analysis, which has been mainly applied in eukaryotic cells, to prokaryotic cells with E. coli serving as a model system. The small size of the E. coli cell introduces unique challenges for applying brightness analysis that are addressed in this work. Photobleaching leads to a depletion of fluorophores and a reduction of the brightness of protein complexes. In addition, the E. coli cell and the point spread function of the instrument only partially overlap, which influences intensity fluctuations. To address these challenges we developed MSQ analysis, which is based on the mean Q-value of segmented photon count data, and combined it with the analysis of axial scans through the E. coli cell. The MSQ method recovers brightness, concentration, and diffusion time of soluble proteins in E. coli. We applied MSQ to measure the brightness of EGFP in E. coli and compared it to solution measurements. We further used MSQ analysis to determine the oligomeric state of nuclear transport factor 2 labeled with EGFP expressed in E. coli cells. The results obtained demonstrate the feasibility of quantifying the stoichiometry of proteins by brightness analysis in a prokaryotic cell.

  2. Large-scale protein-protein interaction analysis in Arabidopsis mesophyll protoplasts by split firefly luciferase complementation.

    Li, Jian-Feng; Bush, Jenifer; Xiong, Yan; Li, Lei; McCormack, Matthew

    2011-01-01

    Protein-protein interactions (PPIs) constitute the regulatory network that coordinates diverse cellular functions. There are growing needs in plant research for creating protein interaction maps behind complex cellular processes and at a systems biology level. However, only a few approaches have been successfully used for large-scale surveys of PPIs in plants, each having advantages and disadvantages. Here we present split firefly luciferase complementation (SFLC) as a highly sensitive and noninvasive technique for in planta PPI investigation. In this assay, the separate halves of a firefly luciferase can come into close proximity and transiently restore its catalytic activity only when their fusion partners, namely the two proteins of interest, interact with each other. This assay was conferred with quantitativeness and high throughput potential when the Arabidopsis mesophyll protoplast system and a microplate luminometer were employed for protein expression and luciferase measurement, respectively. Using the SFLC assay, we could monitor the dynamics of rapamycin-induced and ascomycin-disrupted interaction between Arabidopsis FRB and human FKBP proteins in a near real-time manner. As a proof of concept for large-scale PPI survey, we further applied the SFLC assay to testing 132 binary PPIs among 8 auxin response factors (ARFs) and 12 Aux/IAA proteins from Arabidopsis. Our results demonstrated that the SFLC assay is ideal for in vivo quantitative PPI analysis in plant cells and is particularly powerful for large-scale binary PPI screens.

  3. Large-scale protein-protein interaction analysis in Arabidopsis mesophyll protoplasts by split firefly luciferase complementation.

    Jian-Feng Li

    Full Text Available Protein-protein interactions (PPIs constitute the regulatory network that coordinates diverse cellular functions. There are growing needs in plant research for creating protein interaction maps behind complex cellular processes and at a systems biology level. However, only a few approaches have been successfully used for large-scale surveys of PPIs in plants, each having advantages and disadvantages. Here we present split firefly luciferase complementation (SFLC as a highly sensitive and noninvasive technique for in planta PPI investigation. In this assay, the separate halves of a firefly luciferase can come into close proximity and transiently restore its catalytic activity only when their fusion partners, namely the two proteins of interest, interact with each other. This assay was conferred with quantitativeness and high throughput potential when the Arabidopsis mesophyll protoplast system and a microplate luminometer were employed for protein expression and luciferase measurement, respectively. Using the SFLC assay, we could monitor the dynamics of rapamycin-induced and ascomycin-disrupted interaction between Arabidopsis FRB and human FKBP proteins in a near real-time manner. As a proof of concept for large-scale PPI survey, we further applied the SFLC assay to testing 132 binary PPIs among 8 auxin response factors (ARFs and 12 Aux/IAA proteins from Arabidopsis. Our results demonstrated that the SFLC assay is ideal for in vivo quantitative PPI analysis in plant cells and is particularly powerful for large-scale binary PPI screens.

  4. Analysis of fresco paintings by X-ray fluorescence method

    Cechak, T.; Gerndt, J.; Musilek, L.; Kopecka, I.

    2000-01-01

    In this work we present the application of X-ray fluorescence analysis (XRFA) to examine fresco paintings from the Karlstejn castle. The X-ray fluorescence apparatus built and operated in the Laboratory of Quantitative Methods in Research of Ancient Monuments was used for the purpose of fresco paintings measurements. The X-ray sources (radionuclides) generate the characteristic X-ray photons from the sample. The Si(Li) detector measures numbers and energies of photons emitted from the specimen. The energy and number of photons detected can be converted into kind and amount of measured atoms. These results give data for qualitative and quantitative analysis of samples. XRFA is relatively simple and non-destructive method. Capability of in-situ measurement is one of big advantages of this method. The radionuclide sources of exciting radiation (e.g. 55 Fe enables the excitation of elements with Z up to 23, 238 Pu is used in interval of Z from 20 to 39 etc.) were used. An Si(Li) semiconductor detector with a 5 l Dewar vessel and portable spectroscopy system enable the in situ measurement. Narrow collimation of the exciting beam makes it possible to select the measured area of fresco painting. The valuable fresco paintings from the Karlstejn castle were investigated in this way. The measurements were carried out in collaboration with the Analytical Laboratory of the State Institute for the Preservation of Historic Monuments. A suitable analysis of paintings makes it possible to detect the kind of colours and evaluate changes in the surface colour of paintings and suggest useful and timely procedures for their conservation and restoration. (author)

  5. Gaseous detectors for energy dispersive X-ray fluorescence analysis

    Veloso, J. F. C. A.; Silva, A. L. M.

    2018-01-01

    The energy resolution capability of gaseous detectors is being used in the last years to perform studies on the detection of characteristic X-ray lines emitted by elements when excited by external radiation sources. One of the most successful techniques is the Energy Dispersive X-ray Fluorescence (EDXRF) analysis. Recent developments in the new generation of micropatterned gaseous detectors (MPGDs), triggered the possibility not only of recording the photon energy, but also of providing position information, extending their application to EDXRF imaging. The relevant features and strategies to be applied in gaseous detectors in order to better fit the requirements for EDXRF imaging will be reviewed and discussed, and some application examples will be presented.

  6. Uranium concentrate analysis by X-ray fluorescence spectroscopy

    Diaz-Guerra, J.P.; Bayon, A.; Roca, R.

    1978-01-01

    The determination of As, Ca, Fe, Mo, P, S, Si. Th, V and U in uranium concentrates by X-ray fluorescence spectroscopy has been studied. As and U are determined in nitric solutions and for the rest of elements analysis is performed by a bead fusion technique using Li 2 B 4 O 7 and Li 2 CO 3 as fluxes. Although the uranium matrix minimizes the absorption and enhancement effects, because of the content variations of this element it is advisable to operate at a constant level of U 3 O 8 . Despite the high matrix absorption and the large dilution of the samples, sensitivity and speed are found to be satisfactory as the result of the use of a high sensitivity automatic spectrometer. The spectral interferences of Mo on S and P, and of Pb on As have been particularly considered. (author) [es

  7. CSF coccidioides complement fixation

    ... this page: //medlineplus.gov/ency/article/003526.htm CSF coccidioides complement fixation test To use the sharing features on this page, please enable JavaScript. CSF coccidioides complement fixation is a test that checks ...

  8. Expression, purification, cocrystallization and preliminary crystallographic analysis of sucrose octasulfate/human complement regulator factor H SCRs 6–8

    Prosser, Beverly E.; Johnson, Steven; Roversi, Pietro [The Sir William Dunn School of Pathology, The University of Oxford, South Parks Road, Oxford OX1 3RE (United Kingdom); Clark, Simon J. [Faculty of Life Sciences, Manchester University, Michael Smith Building, Oxford Road, Manchester M13 9PT (United Kingdom); Tarelli, Edward [Medical Biomics Centre, St George’s, University of London, Cranmer Terrace, London SW17 0RE (United Kingdom); Sim, Robert B. [The MRC Immunochemistry Unit, The University of Oxford, South Parks Road, Oxford OX1 3RE (United Kingdom); Day, Antony J. [Faculty of Life Sciences, Manchester University, Michael Smith Building, Oxford Road, Manchester M13 9PT (United Kingdom); Lea, Susan M., E-mail: susan.lea@bnc.ox.ac.uk [The Sir William Dunn School of Pathology, The University of Oxford, South Parks Road, Oxford OX1 3RE (United Kingdom)

    2007-06-01

    The crystallization of human complement regulator FH-678{sub 402H} with a glycosaminoglycan analogue is described. Human plasma protein complement factor H (FH) is an inhibitor of the spontaneously activated alternative complement pathway. An allotypic variant of FH, 402His, has been associated with age-related macular degeneration, the leading cause of blindness in the elderly. Crystals of FH domains 6–8 (FH678) containing 402His have been grown in the presence of a polyanionic sucrose octasulfate ligand (an analogue of the natural glycosaminoglycan ligands of FH) using both native and selenomethionine-derivatized protein. Native data sets diffracting to 2.3 Å and SeMet data sets of up to 2.8 Å resolution have been collected. An anomalous difference Patterson map reveals self- and cross-peaks from two incorporated Se atoms. The corresponding selenium substructure has been solved.

  9. SIMA: Python software for analysis of dynamic fluorescence imaging data

    Patrick eKaifosh

    2014-09-01

    Full Text Available Fluorescence imaging is a powerful method for monitoring dynamic signals in the nervous system. However, analysis of dynamic fluorescence imaging data remains burdensome, in part due to the shortage of available software tools. To address this need, we have developed SIMA, an open source Python package that facilitates common analysis tasks related to fluorescence imaging. Functionality of this package includes correction of motion artifacts occurring during in vivo imaging with laser-scanning microscopy, segmentation of imaged fields into regions of interest (ROIs, and extraction of signals from the segmented ROIs. We have also developed a graphical user interface (GUI for manual editing of the automatically segmented ROIs and automated registration of ROIs across multiple imaging datasets. This software has been designed with flexibility in mind to allow for future extension with different analysis methods and potential integration with other packages. Software, documentation, and source code for the SIMA package and ROI Buddy GUI are freely available at http://www.losonczylab.org/sima/.

  10. UV irradiation analysis of complementation between, and replication of, RNA-negative temperature-sensitivie mutants of Newcastle disease virus

    Peeples, M.E.; Bratt, M.A.

    1982-01-01

    Random uv irradiation-induced lesions destroy the infectivity of Newcastle disease virus (NDV) by blocking downstream transcription from the single viral promoter. The nucleocapsid-associated polypeptides most likely to be involved in RNA synthesis are located at the extreme ends of the genome: NP and P are promoter proximal genes, and L is the most distal gene. We attempted to order the two temperature-sensitive (ts) RNA-negative (RNA-) mutant groups of NDV by determining the uv target sizes for the complementing abilities of mutants A1 and E1. After uv irradiation, E1 was unable to complement A1, a result compatible with the A mutation lying in the L gene. In contrast, after uv irradiation A1 was able to complement E1 for both virus production and viral protein synthesis, with a target size most consistent with the E mutation lying in the P gene. UV-irradiated virus was unable to replicate as indicated by its absence in the yields of multiply infected cells, either as infectious virus or as particles with complementing activity. After irradiation, ts mutant B1ΔP, with a non-ts mutation affecting the electrophoretic mobility of the P protein, complemented E1 in a manner similar to A1, but it did not amplify the expression of ΔP in infected cells. This too is consistent with irradiated virus being unable to replicate despite the presence of the components needed for replication of E1. At high uv doses, A1 was able to complement E1 in a different, uv-resistant manner, probably by direct donation of input polypeptides. Multiplicity reactivation has previously been observed at high-multiplicity infection by uv-irradiated paramyxoviruses. In this case, virions which are noninfectious because they lack a protein component may be activated by a protein from irradiated virions

  11. Comparative genomic analysis of multi-subunit tethering complexes demonstrates an ancient pan-eukaryotic complement and sculpting in Apicomplexa.

    Christen M Klinger

    Full Text Available Apicomplexa are obligate intracellular parasites that cause tremendous disease burden world-wide. They utilize a set of specialized secretory organelles in their invasive process that require delivery of components for their biogenesis and function, yet the precise mechanisms underpinning such processes remain unclear. One set of potentially important components is the multi-subunit tethering complexes (MTCs, factors increasingly implicated in all aspects of vesicle-target interactions. Prompted by the results of previous studies indicating a loss of membrane trafficking factors in Apicomplexa, we undertook a bioinformatic analysis of MTC conservation. Building on knowledge of the ancient presence of most MTC proteins, we demonstrate the near complete retention of MTCs in the newly available genomes for Guillardiatheta and Bigelowiellanatans. The latter is a key taxonomic sampling point as a basal sister taxa to the group including Apicomplexa. We also demonstrate an ancient origin of the CORVET complex subunits Vps8 and Vps3, as well as the TRAPPII subunit Tca17. Having established that the lineage leading to Apicomplexa did at one point possess the complete eukaryotic complement of MTC components, we undertook a deeper taxonomic investigation in twelve apicomplexan genomes. We observed excellent conservation of the VpsC core of the HOPS and CORVET complexes, as well as the core TRAPP subunits, but sparse conservation of TRAPPII, COG, Dsl1, and HOPS/CORVET-specific subunits. However, those subunits that we did identify appear to be expressed with similar patterns to the fully conserved MTC proteins, suggesting that they may function as minimal complexes or with analogous partners. Strikingly, we failed to identify any subunits of the exocyst complex in all twelve apicomplexan genomes, as well as the dinoflagellate Perkinsus marinus. Overall, we demonstrate reduction of MTCs in Apicomplexa and their ancestors, consistent with modification during

  12. A systematic analysis of the complement pathways in patients with neuromyelitis optica indicates alteration but no activation during remission

    Veszeli, Nóra; Füst, György; Csuka, Dorottya

    2014-01-01

    Neuromyelitis optica (NMO) is an autoimmune demyelinating inflammatory disorder, mediated by pathogenic autoantibodies against aquaporin 4 (AQP4), the main water channel of the central nervous system (CNS). NMO is characterized by local IgG deposition and complement activation within the CNS...

  13. Assembly and activation of alternative complement components on endothelial cell-anchored ultra-large von Willebrand factor links complement and hemostasis-thrombosis.

    Nancy A Turner

    Full Text Available Vascular endothelial cells (ECs express and release protein components of the complement pathways, as well as secreting and anchoring ultra-large von Willebrand factor (ULVWF multimers in long string-like structures that initiate platelet adhesion during hemostasis and thrombosis. The alternative complement pathway (AP is an important non-antibody-requiring host defense system. Thrombotic microangiopathies can be associated with defective regulation of the AP (atypical hemolytic-uremic syndrome or with inadequate cleavage by ADAMTS-13 of ULVWF multimeric strings secreted by/anchored to ECs (thrombotic thrombocytopenic purpura. Our goal was to determine if EC-anchored ULVWF strings caused the assembly and activation of AP components, thereby linking two essential defense mechanisms.We quantified gene expression of these complement components in cultured human umbilical vein endothelial cells (HUVECs by real-time PCR: C3 and C5; complement factor (CF B, CFD, CFP, CFH and CFI of the AP; and C4 of the classical and lectin (but not alternative complement pathways. We used fluorescent microscopy, monospecific antibodies against complement components, fluorescent secondary antibodies, and the analysis of >150 images to quantify the attachment of HUVEC-released complement proteins to ULVWF strings secreted by, and anchored to, the HUVECs (under conditions of ADAMTS-13 inhibition. We found that HUVEC-released C4 did not attach to ULVWF strings, ruling out activation of the classical and lectin pathways by the strings. In contrast, C3, FB, FD, FP and C5, FH and FI attached to ULVWF strings in quantitative patterns consistent with assembly of the AP components into active complexes. This was verified when non-functional FB blocked the formation of AP C3 convertase complexes (C3bBb on ULVWF strings.AP components are assembled and activated on EC-secreted/anchored ULVWF multimeric strings. Our findings provide one possible molecular mechanism for clinical

  14. Renal function measured by X-ray fluorescence analysis

    Boijsen, M.; Jacobsson, L.; Tylen, U.; Sahlgrenska Sjukhuset, Goeteborg

    1987-01-01

    In twenty-six patients injected with metrizoate during urography, plasma was analyzed for iodine concentration using X-ray fluorescence analysis, and total plasma clearance of contrast medium was calculated. Total plasma clearance of 51 Cr-EDTA was also determined, but not simultaneously, in order to find out if the urographic procedure would influence the kidneys to such an extent that the contrast medium clearance value would differ much from the 51 Cr-EDTA clearance value. The errors in the method were assessed and the total error of the contrast medium clearance determination was calculated. When comparing 51 Cr-EDTA and metrizoate clearance a correlation of 0.94 and a mean ratio of 1.046 (SD 0.138) was found. The assessable errors cannot fully explain the standard deviation, which might indicate a transient change in kidney function related to elements of the urographic procedure such as laxation with possible dehydration and/or the contrast medium dose. (orig.)

  15. Radioisotope sources for X-ray fluorescence analysis

    Leonowich, J.; Pandian, S.; Preiss, I.L.

    1977-01-01

    Problems involved in developing radioisotope sources and the characteristics of potentially useful radioisotopes for X-ray fluorescence analysis are presented. These include the following. The isotope must be evaluated for the physical and chemical forms available, purity, half-life, specific activity, toxicity, and cost. The radiation hazards of the source must be considered. The type and amount of radiation output of the source must be evaluated. The source construction must be planned. The source should also present an advance over those currently available in order to justify its development. Some of the isotopes, which are not in use but look very promising, are indicated, and their data are tabulated. A more or less ''perfect'' source within a given range of interest would exhibit the following characteristics. (1) Decay by an isometric transition with little or no internal conversion, (2) Have an intense gamma transition near the absorption edge of the element(s) of interest with no high energy gammas, (3) Have a sufficiently long half-life (in the order of years) for both economic and calibration reasons, (4) Have a sufficiently large cross-section for production in a reasonable amount of time. If there are competing reactions the interfering isotopes should be reasonably short-lived, or if not, be apt to be separated from the isotope chemically with a minimum of difficulty. (T.G.)

  16. TRANES analysis of the fluorescence of nile red in organized ...

    Unknown

    Department of Chemical Sciences, Tata Institute of Fundamental Research, ... Construction of time-resolved emission spectra (TRES) is a useful method 1. If the ..... 1992–2000 Topics in fluorescence spectroscopy (New York: Plenum) vol. 1–5 ...

  17. X-ray fluorescence analysis of Fe - Ni - Mo systems

    Belyaev, E.E.; Ershov, A.V.; Mashin, A.I.; Mashin, N.I.; Rudnevskij, N.K.

    1998-01-01

    Procedures for the X-ray fluorescence determination of the composition and thickness of Fe - Ni - Mo thin films and the concentration of elements in thick films of the Fe - Ni - Mo alloy are developed [ru

  18. Preparation of specimens for analysis by: X-ray diffraction and X-ray fluorescence analysis

    Banos L, L.

    2004-01-01

    Specimen preparation is one of the most important requirements in the analysis of samples by X-ray Diffraction and X-ray Fluorescence. This statement is especially true for samples containing different types of materials. There are many forms of specimen suitable for X-ray analysis and the type of the sample as received will generally determine the method of pretreatment. It is convenient to refer to the material received for analysis as the sample, and that, which is actually analyzed as the specimen. The powder Diffraction method assumes that the particles in the specimen are ideally random orientation and that there are enough crystallites in the specimen to achieve a representative intensity distribution for these crystallites. X ray Fluorescence is essentially a comparative method of analysis, it is vital that all standards and unknowns be presented to the spectrometer in a reproducible and identical manner. (Author) 3 refs., 6 figs

  19. Application of instrumental neutron activation analysis and X-ray fluorescence analysis in art pieces investigation

    Panczyk, E.; Kierzek, J.; Walis, L.; Ligeza, M.

    1996-01-01

    The application of instrumental neutron activation analysis have been shown for the trace element identification in dyes of old painting and other art objects. The recognition of their composition is a important measure for attribution. Also the X-ray fluorescence analysis has been frequently used for examination of art objects. The age determination of the old chinese porcelain is a good example described in the paper. 20 refs, 4 figs

  20. Complementing approaches to demonstrate chlorinated solvent biodegradation in a complex pollution plume: mass balance, PCR and compound-specific stable isotope analysis.

    Courbet Christelle; Rivière Agnès; Jeannottat Simon; Rinaldi Sandro; Hunkeler Daniel; Bendjoudi Hocine; De Marsily Ghislain

    2011-01-01

    This work describes the use of different complementing methods (mass balance polymerase chain reaction assays and compound specific stable isotope analysis) to demonstrate the existence and effectiveness of biodegradation of chlorinated solvents in an alluvial aquifer. The solvent contaminated site is an old chemical factory located in an alluvial plain in France. As most of the chlorinated contaminants currently found in the groundwater at this site were produced by local industries at vario...

  1. Romanian medieval earring analysis by X-ray fluorescence technique

    Therese, Laurent; Guillot, Philippe; Muja, Cristina

    2011-01-01

    Full text: Several instrumental techniques of elemental analysis are now used for the characterization of archaeological materials. The combination between archaeological and analytical information can provide significant knowledge on the constituting material origin, heritage authentication and restoration, provenance, migration, social interaction and exchange. Surface mapping techniques such as X-Ray Fluorescence have become a powerful tool for obtaining qualitative and semi-quantitative information about the chemical composition of cultural heritage materials, including metallic archaeological objects. In this study, the material comes from the Middle Age cemetery of Feldioara (Romania). The excavation of the site located between the evangelical church and the parsonage led to the discovery of several funeral artifacts in 18 graves among a total of 127 excavated. Even if the inventory was quite poor, some of the objects helped in establishing the chronology. Six anonymous Hungarian denarii (silver coins) were attributed to Geza II (1141-1161) and Stefan III (1162-1172), placing the cemetery in the second half of the XII century. This period was also confirmed by three loop shaped earrings with the end in 'S' form (one small and two large earrings). The small earring was found during the excavation in grave number 86, while the two others were discovered together in grave number 113. The anthropological study shown that skeletons excavated from graves 86 and 113 belonged respectively to a child (1 individual, medium level preservation, 9 months +/- 3 months) and to an adult (1 individual). In this work, elemental mapping were obtained by X-ray fluorescence (XRF) technique from Jobin Yvon Horiba XGT-5000 instrument offering detailed elemental images with a spatial resolution of 100μm. The analysis revealed that the earrings were composed of copper, zinc and tin as major elements. Minor elements were also determined. The comparison between the two large earrings

  2. Romanian medieval earring analysis by X-ray fluorescence technique

    Therese, Laurent; Guillot, Philippe, E-mail: philippe.guillot@univ-jfc.fr [Laboratoire Diagnostics des Plasmas, CUFR J.F.C, Albi (France); Muja, Cristina [Laboratoire Diagnostics des Plasmas, CUFR J.F.C, Albi (France); Faculty of Biology, University of Bucharest (Romania); Vasile Parvan Institute of Archaeology, Bucharest, (Romania)

    2011-07-01

    Full text: Several instrumental techniques of elemental analysis are now used for the characterization of archaeological materials. The combination between archaeological and analytical information can provide significant knowledge on the constituting material origin, heritage authentication and restoration, provenance, migration, social interaction and exchange. Surface mapping techniques such as X-Ray Fluorescence have become a powerful tool for obtaining qualitative and semi-quantitative information about the chemical composition of cultural heritage materials, including metallic archaeological objects. In this study, the material comes from the Middle Age cemetery of Feldioara (Romania). The excavation of the site located between the evangelical church and the parsonage led to the discovery of several funeral artifacts in 18 graves among a total of 127 excavated. Even if the inventory was quite poor, some of the objects helped in establishing the chronology. Six anonymous Hungarian denarii (silver coins) were attributed to Geza II (1141-1161) and Stefan III (1162-1172), placing the cemetery in the second half of the XII century. This period was also confirmed by three loop shaped earrings with the end in 'S' form (one small and two large earrings). The small earring was found during the excavation in grave number 86, while the two others were discovered together in grave number 113. The anthropological study shown that skeletons excavated from graves 86 and 113 belonged respectively to a child (1 individual, medium level preservation, 9 months +/- 3 months) and to an adult (1 individual). In this work, elemental mapping were obtained by X-ray fluorescence (XRF) technique from Jobin Yvon Horiba XGT-5000 instrument offering detailed elemental images with a spatial resolution of 100{mu}m. The analysis revealed that the earrings were composed of copper, zinc and tin as major elements. Minor elements were also determined. The comparison between the two

  3. Background approximation in automatic qualitative X-ray-fluorescent analysis

    Jordanov, J.; Tsanov, T.; Stefanov, R.; Jordanov, N.; Paunov, M.

    1982-01-01

    An empirical method of finding the dependence of the background intensity (Isub(bg) on the wavelength is proposed, based on the approximation of the experimentally found values for the background in the course of an automatic qualitative X-ray fluorescent analysis with pre-set curve. It is assumed that the dependence I(lambda) will be well approximated by a curve of the type Isub(bg)=(lambda-lambda sub(o)sup(fsub(1)(lambda))exp[fsub(2)(lambda)] where fsub(1) (lambda) and f 2 (lambda) are linear functions with respect to the sought parameters. This assumption was checked out on a ''pure'' starch background, in which it is not known beforehand which points belong to the background. It was assumed that the dependence I(lambda) can be found from all minima in the spectrum. Three types of minima has been distinguished: 1. the lowest point between two well-solved X-ray lines; 2. a minimum obtained as a result of statistical fluctuations of the measured signal; 3. the lowest point between two overlapped lines. The minima strongly deviating from the background are removed from the obtained set. The sum-total of the remaining minima serves as a base for the approximation of the dependence I(lambda). The unknown parameters are determined by means of the LSM. The approximated curve obtained by this method is closer to the real background than the background determined by the method described by Kigaki Denki, as the effect of all recorded minima is taken into account. As an example the PbTe spectrum recorded with crystal LiF 220 is shown graphically. The curve well describes the background of the spectrum even in the regions in which there are no minima belonging to the background. (authors)

  4. A guide for approval of x-ray fluorescence analysis devices

    1990-01-01

    This guide has been written to assist manufacturers, distributors and users of x-ray fluorescence analysis devices in the preparation of a submission to the Atomic Energy Control Board (AECB) in support of a request for approval of an x-ray fluorescence analysis device. Prior to the issuance of a Radioisotope licence authorizing the use or possession of an x-ray fluorescence analysis device in Canada, the design and construction of the device must be approved by the AECB. The AECB assessment is limited to the radiation safety aspects of use and packaging for transportation

  5. Radionuclide X-ray fluorescence analysis of components of the environment

    Toelgyessy, J.; Havranek, E.; Dejmkova, E.

    1983-12-01

    The physical foundations and methodology are described of radionuclide X-ray fluorescence analysis. The sources are listed of air, water and soil pollution, and the transfer of impurities into biological materials is described. A detailed description is presented of the sampling of air, soil and biological materials and their preparation for analysis. Greatest attention is devoted to radionuclide X-ray fluorescence analysis of the components of the environment. (ES)

  6. LASER FLUORESCENCE EEM PROBE FOR CONE PENETROMETER POLLUTION ANALYSIS

    A fiber optic LIF (Laser induced fluorescence) EEM (Excitation emission matrix) instrument for CPT deployment has been successfully developed and field tested. The system employs a Nd: YAG laser and Raman shifter as a rugged field portable excitation source. This excitation sou...

  7. Time-resolved fluorescence analysis of the mobile flavin cofactor

    Conformational heterogeneity of the FAD cofactor in -hydroxybenzoate hydroxylase (PHBH) was investigated with time-resolved polarized flavin fluorescence. For binary enzyme/substrate (analogue) complexes of wild-type PHBH and Tyr222 mutants, crystallographic studies have revealed two distinct flavin conformations ...

  8. X-Ray Diffraction and Fluorescence Instrument for Mineralogical Analysis at the Lunar Surface, Phase II

    National Aeronautics and Space Administration — We propose to develop LUNA, a compact and lightweight X-Ray Diffraction (XRD) / X-Ray Fluorescence (XRF) instrument for mineralogical analysis of regolith, rock...

  9. X-Ray Diffraction and Fluorescence Instrument for Mineralogical Analysis at the Lunar Surface, Phase I

    National Aeronautics and Space Administration — We propose to develop a compact and lightweight X-Ray Diffraction (XRD) / X-Ray Fluorescence (XRF) instrument for analysis of mineralogical composition of regolith,...

  10. Sampling, storage and sample preparation procedures for X ray fluorescence analysis of environmental materials

    1997-06-01

    X ray fluorescence (XRF) method is one of the most commonly used nuclear analytical technique because of its multielement and non-destructive character, speed, economy and ease of operation. From the point of view of quality assurance practices, sampling and sample preparation procedures are the most crucial steps in all analytical techniques, (including X ray fluorescence) applied for the analysis of heterogeneous materials. This technical document covers recent modes of the X ray fluorescence method and recent developments in sample preparation techniques for the analysis of environmental materials. Refs, figs, tabs

  11. Principles of fluorescence techniques

    2016-01-01

    Fluorescence techniques are being used and applied increasingly in academics and industry. The Principles of Fluorescence Techniques course will outline the basic concepts of fluorescence techniques and the successful utilization of the currently available commercial instrumentation. The course is designed for students who utilize fluorescence techniques and instrumentation and for researchers and industrial scientists who wish to deepen their knowledge of fluorescence applications. Key scientists in the field will deliver theoretical lectures. The lectures will be complemented by the direct utilization of steady-state and lifetime fluorescence instrumentation and confocal microscopy for FLIM and FRET applications provided by leading companies.

  12. The MicroAnalysis Toolkit: X-ray Fluorescence Image Processing Software

    Webb, S. M.

    2011-01-01

    The MicroAnalysis Toolkit is an analysis suite designed for the processing of x-ray fluorescence microprobe data. The program contains a wide variety of analysis tools, including image maps, correlation plots, simple image math, image filtering, multiple energy image fitting, semi-quantitative elemental analysis, x-ray fluorescence spectrum analysis, principle component analysis, and tomographic reconstructions. To be as widely useful as possible, data formats from many synchrotron sources can be read by the program with more formats available by request. An overview of the most common features will be presented.

  13. Quantification of epithelial cells in coculture with fibroblasts by fluorescence image analysis.

    Krtolica, Ana; Ortiz de Solorzano, Carlos; Lockett, Stephen; Campisi, Judith

    2002-10-01

    To demonstrate that senescent fibroblasts stimulate the proliferation and neoplastic transformation of premalignant epithelial cells (Krtolica et al.: Proc Natl Acad Sci USA 98:12072-12077, 2001), we developed methods to quantify the proliferation of epithelial cells cocultured with fibroblasts. We stained epithelial-fibroblast cocultures with the fluorescent DNA-intercalating dye 4,6-diamidino-2-phenylindole (DAPI), or expressed green fluorescent protein (GFP) in the epithelial cells, and then cultured them with fibroblasts. The cocultures were photographed under an inverted microscope with appropriate filters, and the fluorescent images were captured with a digital camera. We modified an image analysis program to selectively recognize the smaller, more intensely fluorescent epithelial cell nuclei in DAPI-stained cultures and used the program to quantify areas with DAPI fluorescence generated by epithelial nuclei or GFP fluorescence generated by epithelial cells in each field. Analysis of the image areas with DAPI and GFP fluorescences produced nearly identical quantification of epithelial cells in coculture with fibroblasts. We confirmed these results by manual counting. In addition, GFP labeling permitted kinetic studies of the same coculture over multiple time points. The image analysis-based quantification method we describe here is an easy and reliable way to monitor cells in coculture and should be useful for a variety of cell biological studies. Copyright 2002 Wiley-Liss, Inc.

  14. Pathological diagnosis of bladder cancer by image analysis of hypericin induced fluorescence cystoscopic images

    Kah, James C. Y.; Olivo, Malini C.; Lau, Weber K. O.; Sheppard, Colin J. R.

    2005-08-01

    Photodynamic diagnosis of bladder carcinoma based on hypericin fluorescence cystoscopy has shown to have a higher degree of sensitivity for the detection of flat bladder carcinoma compared to white light cystoscopy. The potential of the photosensitizer hypericin-induced fluorescence in performing non-invasive optical biopsy to grade bladder cancer in vivo using fluorescence cystoscopic image analysis without surgical resection for tissue biopsy is investigated in this study. The correlation between tissue fluorescence and histopathology of diseased tissue was explored and a diagnostic algorithm based on fluorescence image analysis was developed to classify the bladder cancer without surgical resection for tissue biopsy. Preliminary results suggest a correlation between tissue fluorescence and bladder cancer grade. By combining both the red-to-blue and red-to-green intensity ratios into a 2D scatter plot yields an average sensitivity and specificity of around 70% and 85% respectively for pathological cancer grading of the three different grades of bladder cancer. Therefore, the diagnostic algorithm based on colorimetric intensity ratio analysis of hypericin fluorescence cystoscopic images developed in this preliminary study shows promising potential to optically diagnose and grade bladder cancer in vivo.

  15. Noun complement clauses as referential modifiers

    Carlos de Cuba

    2017-01-01

    Full Text Available A number of recent analyses propose that so-called noun complement clauses should be analyzed as a type of relative clause. In this paper, I present a number of complications for any analysis that equates noun complement clauses to relative clauses, and conclude that this type of analysis is on the wrong track. I present cross-linguistic evidence showing that the syntactic behavior of noun complement clauses does not pattern with relative clauses. Patterns of complementizer choice and complementizer drop as well as patterns involving main clause phenomena and extraction differ in the two constructions, which I argue is unexpected under a relative clause analysis that involves operator movement. Instead I present an alternative analysis in which I propose that the referentiality of a noun complement clause is linked to its syntactic behavior. Following recent work, I claim that referential clauses have a syntactically truncated left-periphery, and this truncation can account for the lack of main clause phenomena in noun complement clauses. I argue that the truncation analysis is also able to accommodate complementizer data patterns more easily than relative clause analyses that appeal to operator movement.

  16. Simultaneous analysis of gaseous and particulate sulphur in the atmosphere by x-ray fluorescence spectrometry

    Matsuda, Yatsuka; Mamuro, Tetsuo

    1975-01-01

    An analytical technique for the simultaneous measurements of the atmospheric concentrations of SO 2 gas and sulphur absorbed by aerosol particles has been developed. Aerosol particles are collected on membrane filter and at the same time SO 2 gas is captured on alkali impregnated filter. The sulphur content in each filter is measured by an energy dispersive X -ray fluorescence spectrometer consisting of a Si(Li) semiconductor detector connected to a multi-channel pulse height analyzer and an excitation source of 55 Fe. Two methods are acceptable for the determination of the sulphur content in impregnated filter by X-ray fluorescence analysis. In the first method X-ray fluorescence analysis is made after the collected sulphur gas diffused and distributed uniformly enough throughout the filter, and in the second method X-ray fluorescence analysis gas to be finished before the diffusion of the collected sulphur becomes appreciable. (author)

  17. Fluorescent Probes for Analysis and Imaging of Monoamine Oxidase Activity

    Kim, Dokyoung; Jun, Yong Woong; Ahn, Kyo Han [POSTECH, Pohang (Korea, Republic of)

    2014-05-15

    Monoamine oxidases catalyze the oxidative deamination of dietary amines and amine neurotransmitters, and assist in maintaining the homeostasis of the amine neurotransmitters in the brain. Dysfunctions of these enzymes can cause neurological and behavioral disorders including Parkinson's and Alzheimer's diseases. To understand their physiological roles, efficient assay methods for monoamine oxidases are essential. Reviewed in this Perspective are the recent progress in the development of fluorescent probes for monoamine oxidases and their applications to enzyme assays in cells and tissues. It is evident that still there is strong need for a fluorescent probe with desirable substrate selectivity and photophysical properties to challenge the much unsolved issues associated with the enzymes and the diseases.

  18. In situ Analysis of Coral Recruits Using Fluorescence Imaging

    Adi Zweifler

    2017-09-01

    Full Text Available Recruitment is a fundamental process that influences coral population dynamics as well as reef community structure. To date, coral recruitment success rates are poorly quantified because survey methods are labor-intensive and require manual interpretation. Thus, they are prone to human errors and have low repeatability—a gap we aim to bridge in this research. Since both corals and their symbiotic algae contain fluorescent pigments (chlorophyll and fluorescent proteins, we used the non-invasive Fluorescence Imaging System (FluorIS and developed a methodology to acquire daytime fluorescent photographs and identify coral recruits in them. We tested our method by monitoring 20 random quadrats at two sites in the Gulf of Aqaba, Israel. The quadrats were surveyed once a month for 8 months in order to track the settlement, mortality and survival rates of new coral recruits. We demonstrate daytime imaging using our method and identification of coral recruits as small as 1 mm in diameter, in a 20 × 20 cm quadrat. Our results show that this photographic method reduces surveyor errors and improves precision. The surveys revealed that on average, there are ~2 new coral recruit settlements (<2 cm for a quadrat (40 cm2 per month and that 83% of them survive the first month. Our study suggests a relative stability in the Gulf of Aqaba coral population during the survey period. The ability to survey recruits during the day using low-cost, easy-to-use photographic equipment has the potential to contribute significantly to the standardization of coral reef monitoring and management tools, at a time when the world's coral reefs are declining due to local and global stressors.

  19. Method and device for X-ray fluorescence analysis

    Jagoutz, E.; Palme, C.

    1978-01-01

    In the x-ray fluorescence analyzer the useful signal can be completely separated from the spurious signals, and especially the pulse can be determined. For this purpose the output of the radiation detector is connected with a multichannel pulse height discriminator. The measured signal determined in the pulse heigth discriminator may be indicated by a visual display or processed by a computer (coincidence circuits). (DG) [de

  20. Technique of sample preparation for analysis of gasoline and lubricating oils by X-ray fluorescence analysis

    Avila P, P.

    1990-03-01

    The X-ray fluorescence laboratory of the National Institute of Nuclear Research when not having a technique for the analysis of oils it has intended, with this work, to develop a preparation technique for the analysis of the metals of Pb, Cr, Ni, V and Mo in gasolines and oils, by means of the spectrometry by X-ray fluorescence analysis. The obtained results, its will be of great utility for the one mentioned laboratory. (Author)

  1. Synchrotron x-ray microbeam characteristics for x-ray fluorescence analysis

    Iida, Atsuo; Noma, Takashi

    1995-01-01

    X-ray fluorescence analysis using a synchrotron x-ray microprobe has become an indispensable technique for non-destructive micro-analysis. One of the most important parameters that characterize the x-ray microbeam system for x-ray fluorescence analysis is the beam size. For practical analysis, however, the photon flux, the energy resolution and the available energy range are also crucial. Three types of x-ray microbeam systems, including monochromatic and continuum excitation systems, were compared with reference to the sensitivity, the minimum detection limit and the applicability to various types of x-ray spectroscopic analysis. 16 refs., 5 figs

  2. Molecular Detection of Bladder Cancer by Fluorescence Microsatellite Analysis and an Automated Genetic Analyzing System

    Sarel Halachmi

    2007-01-01

    Full Text Available To investigate the ability of an automated fluorescent analyzing system to detect microsatellite alterations, in patients with bladder cancer. We investigated 11 with pathology proven bladder Transitional Cell Carcinoma (TCC for microsatellite alterations in blood, urine, and tumor biopsies. DNA was prepared by standard methods from blood, urine and resected tumor specimens, and was used for microsatellite analysis. After the primers were fluorescent labeled, amplification of the DNA was performed with PCR. The PCR products were placed into the automated genetic analyser (ABI Prism 310, Perkin Elmer, USA and were subjected to fluorescent scanning with argon ion laser beams. The fluorescent signal intensity measured by the genetic analyzer measured the product size in terms of base pairs. We found loss of heterozygocity (LOH or microsatellite alterations (a loss or gain of nucleotides, which alter the original normal locus size in all the patients by using fluorescent microsatellite analysis and an automated analyzing system. In each case the genetic changes found in urine samples were identical to those found in the resected tumor sample. The studies demonstrated the ability to detect bladder tumor non-invasively by fluorescent microsatellite analysis of urine samples. Our study supports the worldwide trend for the search of non-invasive methods to detect bladder cancer. We have overcome major obstacles that prevented the clinical use of an experimental system. With our new tested system microsatellite analysis can be done cheaper, faster, easier and with higher scientific accuracy.

  3. Significant improvement of accuracy and precision in the determination of trace rare earths by fluorescence analysis

    Ozawa, L.; Hersh, H.N.

    1976-01-01

    Most of the rare earths in yttrium, gadolinium and lanthanum oxides emit characteristic fluorescent line spectra under irradiation with photons, electrons and x rays. The sensitivity and selectivity of the rare earth fluorescences are high enough to determine the trace amounts (0.01 to 100 ppM) of rare earths. The absolute fluorescent intensities of solids, however, are markedly affected by the synthesis procedure, level of contamination and crystal perfection, resulting in poor accuracy and low precision for the method (larger than 50 percent error). Special care in preparation of the samples is required to obtain good accuracy and precision. It is found that the accuracy and precision for the determination of trace (less than 10 ppM) rare earths by fluorescence analysis improved significantly, while still maintaining the sensitivity, when the determination is made by comparing the ratio of the fluorescent intensities of the trace rare earths to that of a deliberately added rare earth as reference. The variation in the absolute fluorescent intensity remains, but is compensated for by measuring the fluorescent line intensity ratio. Consequently, the determination of trace rare earths (with less than 3 percent error) is easily made by a photoluminescence technique in which the rare earths are excited directly by photons. Accuracy is still maintained when the absolute fluorescent intensity is reduced by 50 percent through contamination by Ni, Fe, Mn or Pb (about 100 ppM). Determination accuracy is also improved for fluorescence analysis by electron excitation and x-ray excitation. For some rare earths, however, accuracy by these techniques is reduced because indirect excitation mechanisms are involved. The excitation mechanisms and the interferences between rare earths are also reported

  4. Multi-color fluorescent DNA analysis in an integrated optofluidic lab on a chip

    Dongre, C.

    2010-01-01

    Abstract: Sorting and sizing of DNA molecules within the human genome project has enabled the genetic mapping of various illnesses. Furthermore by employing tiny lab-on-a-chip device, integrated DNA sequencing and genetic diagnostics have become feasible. We present the combination of capillary electrophoresis with laser-induced fluorescence for optofluidic integration toward an on-chip bio-analysis tool. Integrated optical fluorescence excitation allows for a high spatial resolution (12 μm) ...

  5. X-ray fluorescence analysis for trace element determination in foodstuff chemistry

    Wildanger, W.

    The physical fundamentals of X-ray fluorescence analysis are given and the routine spectrometers described. The basic principles are given of analytical methods used in qualitative and quantitative fluorescence analyses. Examples are given of the use of the method in a number of fields and the possibility and usefulness is discussed for the determination of trace elements in foodstuffs. The preparation of samples, preliminary concentration of components and calibration methods are discussed. (M.K.)

  6. Rare earth aerosol analysis by x-ray fluorescence spectrometry

    Citron, I.M.; Mausner, L.F.

    1982-01-01

    An analytical method for the determination of four lanthanides in air filter samples is described. The method involves simultaneous quantitative determinations of La, Ce, Pr, and Nd at the microgram level by x-ray fluorescence spectrometry without chemical separation of these rare earths and without serious interferences from the dust matrices on the filters. The method has been used successfully to analyze some air filter samples collected at a rare earth processing refinery in Illinois. A description of the development of the method is given as well as the results obtained by using this method on the air filter samples. The reproducibility of the results was generally +-5%

  7. Microstructural analysis of clayey ceramic incorporated with fluorescent lamp glass

    Morais, A.S.C.; Caldas, T.C.C.; Pereira, P.S.; Monteiro, S.N.; Vieira, C.M.F.

    2011-01-01

    This study aims to evaluate the effect of the incorporation of glass powder fluorescent lamp, from a decontamination process, in the microstructure of clayey ceramic. Formulations were prepared with incorporation of the waste in amounts of up to 10 wt.% into the clayey body. Specimens were prepared by uniaxial mold-press at 20 MPa and then fired at 850 and 1050°C. After firing, the microstructure of the ceramics was evaluated by optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that the incorporation of glass powder into the clayey body changes the microstructure of the ceramics. (author)

  8. Study of the elemental composition of Chenopodium Quinoa Willd by fast neutron activation analysis and X ray fluorescence analysis

    Soto Moran, R.L.; Szegedi, S.; Llopiz, J.L.

    1996-01-01

    By means of x-ray fluorescence and fast neutron activation analysis the nitrogen content has been determined in samples of roots, stems, leaf, flowers and grains from Quinua (Chenopodium Quinoa Willd), which was previously treated with fertilizer

  9. Strategies of molecular imprinting-based fluorescence sensors for chemical and biological analysis.

    Yang, Qian; Li, Jinhua; Wang, Xiaoyan; Peng, Hailong; Xiong, Hua; Chen, Lingxin

    2018-07-30

    One pressing concern today is to construct sensors that can withstand various disturbances for highly selective and sensitive detecting trace analytes in complicated samples. Molecularly imprinted polymers (MIPs) with tailor-made binding sites are preferred to be recognition elements in sensors for effective targets detection, and fluorescence measurement assists in highly sensitive detection and user-friendly control. Accordingly, molecular imprinting-based fluorescence sensors (MI-FL sensors) have attracted great research interest in many fields such as chemical and biological analysis. Herein, we comprehensively review the recent advances in MI-FL sensors construction and applications, giving insights on sensing principles and signal transduction mechanisms, focusing on general construction strategies for intrinsically fluorescent or nonfluorescent analytes and improvement strategies in sensing performance, particularly in sensitivity. Construction strategies are well overviewed, mainly including the traditional indirect methods of competitive binding against pre-bound fluorescent indicators, employment of fluorescent functional monomers and embedding of fluorescence substances, and novel rational designs of hierarchical architecture (core-shell/hollow and mesoporous structures), post-imprinting modification, and ratiometric fluorescence detection. Furthermore, MI-FL sensor based microdevices are discussed, involving micromotors, test strips and microfluidics, which are more portable for rapid point-of-care detection and in-field diagnosing. Finally, the current challenges and future perspectives of MI-FL sensors are proposed. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Analysis of the Color and Fluorescence Alterations of Enamel and Dentin Treated With Hydrogen Peroxide.

    Caneppele, Taciana Marco Ferraz; Rocha Gomes Torres, Carlos; Bresciani, Eduardo

    2015-10-01

    The aim of this study was to evaluate the effect of hydrogen peroxide whitening on fluorescence and color of bovine enamel and dentin. Twenty five dentin discs and 25 enamel discs, with 6 mm diameter and 1 mm thick, were obtained. Direct fluorescence (spectrofluorophotometry) and color (spectrophotometry) were assessed. After fluorescence and color baseline measurements, specimens were immersed in a 35% hydrogen peroxide (HP) solution for 1 h. This procedure was repeated after 7 days. Final fluorescence and color measurements were performed after the second immersion. Chemical characterization of 5 additional specimens was also performed. Data were submitted to repeated analysis of variance and Tukey's test for fluorescence and unpaired t-test for color and chemical components (pwhitening. Enamel presented lower fluorescence than dentin at baseline, but this parameter did not decrease after whitening. Color changes were observed for both substrates, with significantly greater whitening effect in dentin (ΔE=10.37) (pWhitening by hydrogen peroxide induced significant decrease in fluorescence of tooth dentin and promoted significant color changes in dentin and enamel with more accentuated outcomes in dentin.

  11. Plasmonic-based instrument response function for time-resolved fluorescence: toward proper lifetime analysis

    Szlazak, Radoslaw; Tutaj, Krzysztof; Grudzinski, Wojciech; Gruszecki, Wieslaw I.; Luchowski, Rafal, E-mail: rafal.luchowski@umcs.pl [Maria Curie-Sklodowska University, Department of Biophysics, Institute of Physics (Poland)

    2013-06-15

    In this report, we investigated the so-called plasmonic platforms prepared to target ultra-short fluorescence and accurate instrumental response function in a time-domain spectroscopy and microscopy. The interaction of metallic nanoparticles with nearby fluorophores results in the increase of the dye fluorescence quantum yield, photostability and decrease of the lifetime parameter. The mentioned properties of platforms were applied to achieve a picosecond fluorescence lifetime (21 ps) of erythrosin B, used later as a better choice for deconvolution of fluorescence decays measured with 'color' sensitive photo-detectors. The ultra-short fluorescence standard based on combination of thin layers of silver film, silver colloidal nanoparticles (about 60 nm in diameter), and top layer of erythrosin B embedded in 0.2 % poly(vinyl) alcohol. The response functions were monitored on two photo-detectors; microchannel plate photomultiplier and single photon avalanche photodiode as a Rayleigh scattering and ultra-short fluorescence. We demonstrated that use of the plasmonic base fluorescence standard as an instrumental response function results in the absence of systematic error in lifetime measurements and analysis.

  12. Synovitis in mice with inflammatory arthritis monitored with quantitative analysis of dynamic contrast-enhanced NIR fluorescence imaging using iRGD-targeted liposomes as fluorescence probes

    Wu H

    2018-03-01

    Full Text Available Hao Wu,1,2,* Haohan Wu,1,2,* Yanni He,1 Zhen Gan,2 Zhili Xu,1,2 Meijun Zhou,1,2 Sai Liu,1,2 Hongmei Liu1 1Department of Ultrasonography, Guangdong Second Provincial General Hospital Affiliated to Southern Medical University, Guangzhou, China; 2Department of Ultrasonography, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China *These authors contributed equally to this work Background: Rheumatoid arthritis (RA is a common inflammatory disorder characterized primarily by synovitis and pannus formation in multiple joints, causing joints destruction and irreversible disability in most cases. Early diagnosis and effective therapy monitoring of RA are of importance for achieving the favorable prognosis. Methods: We first prepared the targeted fluorescence probes, and then explored the feasibility of near-infrared (NIR fluorescence molecular imaging to detect and evaluate the RA via the targeted fluorescence probes by quantitative analysis in this study. Results: The targeted fluorescence probes (indocyanine green-liposomes decorated with iRGD peptide [iLPs] was successfully prepared. The quantitative analysis found that strong fluorescence signal was detected in inflamed paws and the fluorescence signal in iLPs group was 3.03-fold higher than that in non-targeted (indocyanine green-liposomes decorated without iRGD peptide [LPs] group (P<0.01 at 15 min after injection, whereas the fluorescence signal from iLPs signal can almost not be observed in the non-inflamed paws, showing the high sensitivity and accuracy for arthritis by the NIR fluorescence imaging based on iLPs. Conclusion: The NIR fluorescence imaging by iLPs may facilitate improved arthritis diagnosis and early assessment of the disease progression by providing an in vivo characterization of angiogenesis in inflammatory joint diseases. Keywords: rheumatoid arthritis, synovitis, diagnosis, near-infrared fluorescence imaging, iRGD-targeted probes

  13. X-ray fluorescence analysis of thin films at glancing-incident and -takeoff angles

    Tsuji, K.; Sato, S.; Hirokawa, K.

    1995-01-01

    We have developed a new analytical method, Glancing-Incidence and -Takeoff X-Ray Fluorescence (GIT-XRF) method for the first time. Here, we present an idea for a thin-film analysis and a surface analysis by the GIT-XRF method. In this method, the dependence of the fluorescent x-ray intensity on takeoff angle is measured at various incident angles of the primary x-ray. Compared with a total reflection x-ray fluorescence method, the GIT-XRF method allows a detailed thin-film analysis, because the thin film is cross-checked by many experimental curves. Moreover, a surface-sensitive analysis is also possible by the GIT-XRF method. (author)

  14. MCNP calculation for calibration curve of X-ray fluorescence analysis

    Tan Chunming; Wu Zhifang; Guo Xiaojing; Xing Guilai; Wang Zhentao

    2011-01-01

    Due to the compositional variation of the sample, linear relationship between the element concentration and fluorescent intensity will not be well maintained in most X-ray fluorescence analysis. To overcome this, we use MCNP program to simulate fluorescent intensity of Fe (0∼100% concentration range) within binary mixture of Cr and O which represent typical strong absorption and weak absorption conditions respectively. The theoretic calculation shows that the relationship can be described as a curve determined by parameter p and value of p can be obtained with given absorption coefficient of substrate elements and element under detection. MCNP simulation results are consistent with theoretic calculation. Our research reveals that MCNP program can calculate the Calibration Curve of X-ray fluorescence very well. (authors)

  15. Theoretical study on X-Ray Fluorescence Analysis: Contribution of the self-excitation phenomenon

    RAKOTONDRAJAONA, H.N.J.L.

    1999-01-01

    This work consist in setting up, firstly, fluorescence intensities due to the contribution of secondary and tertiary excitation phenomena which settle among the elements of the same sample during the analysis through X fluorescence, inspired by Sherman calculations. Secondly, we have experimentally checked these expression from the analysis of twelve samples; containing all the following elements: Iron, Copper and Zinc. The difference between the theoretical results and the experimental results has been valued from the formula of the test of χ 2 . We consider that this difference is noticeable compared to other errors due to analysis method. [fr

  16. Evaluation of a fluorescent light densitometer for radiochromic film analysis

    Cheung Tsang; Butson, M.J. E-mail: butsonm@iahs.nsw.gov.au; Yu, P.K.N

    2002-01-01

    Radiochromic film dosimetry used in high energy X-ray detection has been evaluated using a VIDAR VXR-12 digitiser for accuracy and results are compared to other densitometers. The VIDAR scanner uses a broad band fluorescent light source which however, produces a negligible ultraviolet reaction effect on the radiochromic film with an estimated equivalent dose of 0.25 cGy darkening per scan to MD-55-2 film. By varying the exposure setting on the scanner, more accurate information can be obtained using radiochromic film within a certain optical density range. Over the range of 0-20 Gy, the scanner can accurately measure dose with a standard deviation of 1.8% calculated between the measured values and a polynomial fit to data. The VIDAR scanner is shown to be a suitable densitometer for radiochromic film.

  17. Evaluation of a fluorescent light densitometer for radiochromic film analysis

    Cheung Tsang; Butson, M.J.; Yu, P.K.N.

    2002-01-01

    Radiochromic film dosimetry used in high energy X-ray detection has been evaluated using a VIDAR VXR-12 digitiser for accuracy and results are compared to other densitometers. The VIDAR scanner uses a broad band fluorescent light source which however, produces a negligible ultraviolet reaction effect on the radiochromic film with an estimated equivalent dose of 0.25 cGy darkening per scan to MD-55-2 film. By varying the exposure setting on the scanner, more accurate information can be obtained using radiochromic film within a certain optical density range. Over the range of 0-20 Gy, the scanner can accurately measure dose with a standard deviation of 1.8% calculated between the measured values and a polynomial fit to data. The VIDAR scanner is shown to be a suitable densitometer for radiochromic film

  18. Analysis of solar blocker through portable X-ray fluorescence

    Ferreira, Diego de Dio; Melquiades, Fabio Luiz; Appoloni, Carlos Roberto; Lopes, Fabio; Lonni, Audrey Stinghen G.; Oliveira, Frederico Minardi de; Duarte, Jose C.

    2009-01-01

    This paper estimates the concentration of TiO 2 by Energy Dispersion X-ray fluorescence (EDXRF) viewing t obtain the FPS due to the physical barrier in the composition of solar blockers, and identifies possible present metals in the samples. A portable EDXRF equipment was used and 27 commercial of different brands and solar protection factors were analysed. Also, three formulations (A, B and C) were prepared and measured estimated in FPS-30 using 5% or TiO 2 . The quantification was performed through calibration curves with 1% to 30% standards of TiO 2 . As result, it was possible to determine the contribution to physical protection in the FPS, associated to the Ti concentration present in some solar blocker samples available in the market. Also, it was possible to detect the presence of various metals in solar protectors, such as Fe, Zn, Br and Sr, and identify chemical elements which were not mentioned and their formulation as well

  19. Compositional analysis of steels by x-ray fluorescence spectrometry

    Kutty, K.V.G.; Rajagopalan, S.; Ananthakrishnan, S.K.; Asuvatharaman, R.

    1988-01-01

    The x-ray fluorescence spectrometric method of determining Ni, Cr, Mn, Mo, T i, Si and Co in austenitic, ferritic, titanium-stabilised and low alloy steels is described. Samples in the bulk solid form (25-50 mm diameter and upto 50 mm height) or very small samples having a flat surface at least 5 mm in diameter are analysed as received after a brief surface treatment. The complex matrix effects affecting the determination of the various elements are discussed. The direct calibration method as well as the mathematical method of empirical coefficients of overcoming the matrix effects is described. The precision and accuracy of the analyses are discussed. (author). 10 refs

  20. Analysis of Septin Reorganization at Cytokinesis Using Polarized Fluorescence Microscopy

    Molly McQuilken

    2017-05-01

    Full Text Available Septins are conserved filament-forming proteins that act in diverse cellular processes. They closely associate with membranes and, in some systems, components of the cytoskeleton. It is not well understood how filaments assemble into higher-order structures in vivo or how they are remodeled throughout the cell cycle. In the budding yeast S. cerevisiae, septins are found through most of the cell cycle in an hourglass organization at the mother-bud neck until cytokinesis when the collar splits into two rings that disassemble prior to the next cell cycle. Experiments using polarized fluorescence microscopy have suggested that septins are arranged in ordered, paired filaments in the hourglass and undergo a coordinated 90° reorientation during splitting at cytokinesis. This apparent reorganization could be due to two orthogonal populations of filaments disassembling and reassembling or being preferentially retained at cytokinesis. In support of this idea, we report a decrease in septin concentration at the mother-bud neck during cytokinesis consistent with other reports and the timing of the decrease depends on known septin regulators including the Gin4 kinase. We took a candidate-based approach to examine what factors control reorientation during splitting and used polarized fluorescence microscopy to screen mutant yeast strains deficient in septin interacting proteins. Using this method, we have linked known septin regulators to different aspects of the assembly, stability, and reorganization of septin assemblies. The data support that ring splitting requires Gin4 activity and an anillin-like protein Bud4, and normal accumulation of septins at the ring requires phosphorylation of Shs1. We found distinct regulatory requirements for septin organization in the hourglass compared to split rings. We propose that septin subpopulations can vary in their localization and assembly/disassembly behavior in a cell-cycle dependent manner at cytokinesis.

  1. Peroxisome biogenesis disorders: identification of a new complementation group distinct from peroxisome-deficient CHO mutants and not complemented by human PEX 13

    Shimozawa, N.; Suzuki, Y.; Zhang, Z.; Imamura, A.; Tsukamoto, T.; Osumi, T.; Tateishi, K.; Okumoto, K.; Fujiki, Y.; Orii, T.; Barth, P. G.; Wanders, R. J.; Kondo, N.

    1998-01-01

    Ten complementation groups of generalized peroxisome biogenesis disorders (PBD), (excluding rhizomelic chondrodysplasia punctata) have been identified using complementation analysis. Four of the genes involved have been identified using two different methods of (1) genetic functional complementation

  2. Photon induced x-ray fluorescence analysis using energy dispersive detector and dichotomous sampler

    Jaklevic, J.M.; Loo, B.W.; Goulding, F.S.

    1976-01-01

    Operating experience in using the photon-excited energy-dispersive x-ray fluorescence analysis system has demonstrated the applicability of this technique to large-scale air-sampling networks. This experience has shown that it is possible to perform automatic sampling and analysis of aerosol particulates at a sensitivity and accuracy more than adequate for most air pollution studies

  3. TRACE ANALYSIS BY LASER-EXCITED ATOMIC FLUORESCENCE WITH ATOMIZATION IN A PULSED PLASMA

    Lunyov , O.; Oshemkov , S.; Petrov , A.

    1991-01-01

    The possibilities of plasma atomization for laser fluorescence trace analysis are discussed. Pulsed hot hollow cathode discharge was used for analysis of solutions and powdered samples. The high voltage spark and laser-induced breakdown (laser spark) were used as atomizers of metal-containing atmospheric aerosols. Detection limits were improved by means of temporal background selection.

  4. Abstracts of the 8th Conference on total reflection x-ray fluorescence analysis and related methods

    Wobrauschek, P.

    2000-01-01

    The 8. conference on total reflection x-ray fluorescence analysis and related methods held from 25.9 to 29.9.2000 contains 79 abstracts about x-ray fluorescence analysis (XRFA) as a powerful tool used for industrial production, geological prospecting and for environmental control. Total reflection x-ray fluorescence spectroscopy is also a tool used for chemical analysis in medicine, industry and research. (E.B.)

  5. Facilitating in vivo tumor localization by principal component analysis based on dynamic fluorescence molecular imaging

    Gao, Yang; Chen, Maomao; Wu, Junyu; Zhou, Yuan; Cai, Chuangjian; Wang, Daliang; Luo, Jianwen

    2017-09-01

    Fluorescence molecular imaging has been used to target tumors in mice with xenograft tumors. However, tumor imaging is largely distorted by the aggregation of fluorescent probes in the liver. A principal component analysis (PCA)-based strategy was applied on the in vivo dynamic fluorescence imaging results of three mice with xenograft tumors to facilitate tumor imaging, with the help of a tumor-specific fluorescent probe. Tumor-relevant features were extracted from the original images by PCA and represented by the principal component (PC) maps. The second principal component (PC2) map represented the tumor-related features, and the first principal component (PC1) map retained the original pharmacokinetic profiles, especially of the liver. The distribution patterns of the PC2 map of the tumor-bearing mice were in good agreement with the actual tumor location. The tumor-to-liver ratio and contrast-to-noise ratio were significantly higher on the PC2 map than on the original images, thus distinguishing the tumor from its nearby fluorescence noise of liver. The results suggest that the PC2 map could serve as a bioimaging marker to facilitate in vivo tumor localization, and dynamic fluorescence molecular imaging with PCA could be a valuable tool for future studies of in vivo tumor metabolism and progression.

  6. On-line analysis of algae in water by discrete three-dimensional fluorescence spectroscopy.

    Zhao, Nanjing; Zhang, Xiaoling; Yin, Gaofang; Yang, Ruifang; Hu, Li; Chen, Shuang; Liu, Jianguo; Liu, Wenqing

    2018-03-19

    In view of the problem of the on-line measurement of algae classification, a method of algae classification and concentration determination based on the discrete three-dimensional fluorescence spectra was studied in this work. The discrete three-dimensional fluorescence spectra of twelve common species of algae belonging to five categories were analyzed, the discrete three-dimensional standard spectra of five categories were built, and the recognition, classification and concentration prediction of algae categories were realized by the discrete three-dimensional fluorescence spectra coupled with non-negative weighted least squares linear regression analysis. The results show that similarities between discrete three-dimensional standard spectra of different categories were reduced and the accuracies of recognition, classification and concentration prediction of the algae categories were significantly improved. By comparing with that of the chlorophyll a fluorescence excitation spectra method, the recognition accuracy rate in pure samples by discrete three-dimensional fluorescence spectra is improved 1.38%, and the recovery rate and classification accuracy in pure diatom samples 34.1% and 46.8%, respectively; the recognition accuracy rate of mixed samples by discrete-three dimensional fluorescence spectra is enhanced by 26.1%, the recovery rate of mixed samples with Chlorophyta 37.8%, and the classification accuracy of mixed samples with diatoms 54.6%.

  7. Computed microtomography and X-ray fluorescence analysis for comprehensive analysis of structural changes in bone.

    Buzmakov, Alexey; Chukalina, Marina; Nikolaev, Dmitry; Schaefer, Gerald; Gulimova, Victoria; Saveliev, Sergey; Tereschenko, Elena; Seregin, Alexey; Senin, Roman; Prun, Victor; Zolotov, Denis; Asadchikov, Victor

    2013-01-01

    This paper presents the results of a comprehensive analysis of structural changes in the caudal vertebrae of Turner's thick-toed geckos by computer microtomography and X-ray fluorescence analysis. We present algorithms used for the reconstruction of tomographic images which allow to work with high noise level projections that represent typical conditions dictated by the nature of the samples. Reptiles, due to their ruggedness, small size, belonging to the amniote and a number of other valuable features, are an attractive model object for long-orbital experiments on unmanned spacecraft. Issues of possible changes in their bone tissue under the influence of spaceflight are the subject of discussions between biologists from different laboratories around the world.

  8. Computer-assisted sperm morphometry fluorescence-based analysis has potential to determine progeny sex

    Pilar Santolaria

    2016-01-01

    Full Text Available This study was designed to determine the ability of computer-assisted sperm morphometry analysis (CASA-Morph with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa (SX and SY, respectively. Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average (P < 0.001 although with important differences between bulls. A simultaneous evaluation of all the measured features by discriminant analysis revealed that nuclear area and average fluorescence intensity were the variables selected by stepwise discriminant function analysis as the best discriminators between SX and SY. In the second experiment, the sperm nuclear morphometric results from CASA-Morph in nonsexed (mixed SX and SY and sexed (SX semen samples from four bulls were compared. FISH allowed a successful classification of spermatozoa according to their sex chromosome content. X-sexed spermatozoa displayed a larger size and fluorescence intensity than nonsexed spermatozoa (P < 0.05. We conclude that the CASA-Morph fluorescence-based method has the potential to find differences between X- and Y-chromosome-bearing spermatozoa in bovine species although more studies are needed to increase the precision of sex determination by this technique.

  9. X-ray fluorescence analysis of thulium oxide/oxalate for rare earth impurities

    Chandola, L.C.; Khanna, P.P.

    1986-01-01

    An X-ray fluorescence spectrometric method for the analysis of thulium oxide is described. For the analysis, the sample in oxalate form is mixed with boric acid binding material and pressed into a pellet over a supporting pellet of boric acid. A wavelength dispersive Philips PW 1220 X-ray fluorescence spectrometer is used for the experiments; the minimum determination limits are 0.002per cent for Ho, Lu and Y, 0.005per cent for Dy and Er and 0.01per cent for Yb. Calculations for theoretical minimum detection limits and percent standard deviation at each concentration of the standard are carried out. (author)

  10. X-ray fluorescence analysis of lutetium oxide/oxalate for rare earth impurities

    Chandola, L.C.; Khanna, P.P.

    1985-01-01

    An X-ray fluorescence spectrometric method for the analysis of lutetium oxide is described. The sample in the oxalate form is mixed with boric acid binding material and pressed into a pellet over supporting pellet of boric acid. A Philips PW 1220 wavelength dispersive semiautomatic X-ray fluorescence spectrometer is used for the analysis. The minimum determination limit is 0.002 percent for Y, Er and Yb and 0.005 percent for Tm. Calculations for theoretical minimum detection limits and percent standard deviations at each concentration of the standard are carried out. (author)

  11. A portable UV-fluorescence multispectral imaging system for the analysis of painted surfaces

    Comelli, Daniela; Valentini, Gianluca; Nevin, Austin; Farina, Andrea; Toniolo, Lucia; Cubeddu, Rinaldo

    2008-08-01

    A portable fluorescence multispectral imaging system was developed and has been used for the analysis of artistic surfaces. The imaging apparatus exploits two UV lamps for fluorescence excitation and a liquid crystal tunable filter coupled to a low-noise charge coupled device as the image detector. The main features of the system are critically presented, outlining the assets, drawbacks, and practical considerations of portability. A multivariate statistical treatment of spectral data is further considered. Finally, the in situ analysis with the new apparatus of recently restored Renaissance wall paintings is presented.

  12. X-ray fluorescence analysis and optical emission spectrometry of an roman mirror from Tomis, Romania

    Belc, M.; Bogoi, M.; Ionescu, D.; Guita, D.; Caiteanu, S.; Caiteanu, D.

    2000-01-01

    The miscellaneous population of Roman Empire, their diverse cultural tradition, their ability to assimilate the roman civilization spirits, had determined a permanent reassessment superimposed upon the roman contribution. Analysis was undertaken using optical emission spectrometry and non-destructive X-ray fluorescence. X-ray fluorescence analysis is a well-established method and is often used in archaeometry and other work dealing with valuable objects pertaining to the history of art and civilization. Roman mirror analysed has been found not to be made of speculum (a high tin bronze). (authors)

  13. Rapid Analysis and Exploration of Fluorescence Microscopy Images

    Pavie, Benjamin; Rajaram, Satwik; Ouyang, Austin; Altschuler, Jason; Steininger, Robert J; Wu, Lani; Altschuler, Steven

    2014-01-01

    Despite rapid advances in high-throughput microscopy, quantitative image-based assays still pose significant challenges. While a variety of specialized image analysis tools are available, most traditional image-analysis-based workflows have steep learning curves (for fine tuning of analysis parameters) and result in long turnaround times between imaging and analysis. In particular, cell segmentation, the process of identifying individual cells in an image, is a major bottleneck in this regard.

  14. A BIOSENSOR USING COUPLED PLASMON WAVEGUIDE RESONANCE COMBINED WITH HYPERSPECTRAL FLUORESCENCE ANALYSIS

    CHAN DU

    2014-01-01

    Full Text Available We developed a biosensor that is capable for simultaneous surface plasmon resonance (SPR sensing and hyperspectral fluorescence analysis in this paper. A symmetrical metal-dielectric slab scheme is employed for the excitation of coupled plasmon waveguide resonance (CPWR in the present work. Resonance between surface plasmon mode and the guided waveguide mode generates narrower full width half-maximum of the reflective curves which leads to increased precision for the determination of refractive index over conventional SPR sensors. In addition, CPWR also offers longer surface propagation depths and higher surface electric field strengths that enable the excitation of fluorescence with hyperspectral technique to maintain an appreciable signal-to-noise ratio. The refractive index information obtained from SPR sensing and the chemical properties obtained through hyperspectral fluorescence analysis confirm each other to exclude false-positive or false-negative cases. The sensor provides a comprehensive understanding of the biological events on the sensor chips.

  15. Lattices with unique complements

    Saliĭ, V N

    1988-01-01

    The class of uniquely complemented lattices properly contains all Boolean lattices. However, no explicit example of a non-Boolean lattice of this class has been found. In addition, the question of whether this class contains any complete non-Boolean lattices remains unanswered. This book focuses on these classical problems of lattice theory and the various attempts to solve them. Requiring no specialized knowledge, the book is directed at researchers and students interested in general algebra and mathematical logic.

  16. Quantifying the value of investing in distributed natural gas and renewable electricity systems as complements: Applications of discounted cash flow and real options analysis with stochastic inputs

    Pless, Jacquelyn; Arent, Douglas J.; Logan, Jeffrey; Cochran, Jaquelin; Zinaman, Owen

    2016-01-01

    One energy policy objective in the United States is to promote the adoption of technologies that provide consumers with stable, secure, and clean energy. Recent work provides anecdotal evidence of natural gas (NG) and renewable electricity (RE) synergies in the power sector, however few studies quantify the value of investing in NG and RE systems together as complements. This paper uses discounted cash flow analysis and real options analysis to value hybrid NG-RE systems in distributed applications, focusing on residential and commercial projects assumed to be located in the states of New York and Texas. Technology performance and operational risk profiles are modeled at the hourly level to capture variable RE output and NG prices are modeled stochastically as geometric Ornstein-Uhlenbeck (OU) stochastic processes to capture NG price uncertainty. The findings consistently suggest that NG-RE hybrid distributed systems are more favorable investments in the applications studied relative to their single-technology alternatives when incentives for renewables are available. In some cases, NG-only systems are the favorable investments. Understanding the value of investing in NG-RE hybrid systems provides insights into one avenue towards reducing greenhouse gas emissions, given the important role of NG and RE in the power sector. - Highlights: • Natural gas and renewable electricity can be viewed as complements. • We model hybrid natural gas and renewable electricity systems at the hourly level. • We incorporate variable renewable power output and uncertain natural gas prices. • Hybrid natural gas and renewable electricity systems can be valuable investments.

  17. Dissecting virus entry: Replication-independent analysis of virus binding, internalization, and penetration using minimal complementation of β-galactosidase

    Burkard, Christine; Bloyet, Louis Marie; Wicht, Oliver; Van Kuppeveld, Frank J.; Rottier, Peter J M; De Haan, Cornelis A M; Bosch, Berend Jan

    2014-01-01

    Studies of viral entry into host cells often rely on the detection of post-entry parameters, such as viral replication or the expression of a reporter gene, rather than on measuring entry per se. The lack of assays to easily detect the different steps of entry severely hampers the analysis of this

  18. Сomparative Analysis of 0.266 and 0.355 µm Fluorescence Excitation Wavelengths for Laser Fluores-Cence Monitoring of Oil Pollution Detection

    M. L. Belov

    2017-01-01

    Full Text Available The on-line detection of pipeline spillage is really essential for the fast oil spill response to the ecological and economical consequences. However existing on-line pipelines spillage detection systems have a sensibility of 0.2 – 1 % of pipe flow and do not detect the smaller-sized spillages.For unpeopled or sparsely populated regions an advanced technique for detection of pipeline spillages (including low-intensity ones is to monitor oil pollution (petroleum spills on the earth surface along the pipeline using, for example, an air drone.The laser remote sensing method is an effective method to detect the pipelines spillage.The paper is dedicated to development of laser fluorescence detection method of oil pollution. The remote sensing laser method to monitor oil pollution is based on the fluorescence excitation of oil in UV spectral band and on the data record of the earth surface laser-induced fluorescence radiation.For laser fluorescence method of monitoring oil pollution the paper presents a comparative analysis  of 0.266 and 0.355 µm wavelengths of the fluorescence excitation in terms of earth atmosphere propagation, eye-safety, laser characteristics, and petroleum fluorescence excitation efficiency.It is shown that in terms of eye-safety, laser characteristics, and propagation in the earth atmosphere a 0.355 µm laser wavelength of the fluorescence excitation has a sure advantage.In the context of petroleum fluorescence excitation efficiency a 0.266 µm laser wavelength of the fluorescence excitation has the advantage, but this advantage depends heavily on the petroleum base. For low-sulfur (sweet oil for instance,  it is not that big.At large, in solving the task of oil pollution detection because of the oil pipeline spillages the 0.355 µm wavelength of fluorescence excitation ought to be preferable. However, when creating a monitoring system for the pipeline with a specific petroleum base the irreversible decision depends on the

  19. X-ray fluorescence analysis of metal concentration in an alloy electroplating bath

    Hines, R.A.

    1980-06-01

    An energy-dispersive x-ray fluorescence analysis system has been developed for rapid, simultaneous analysis of gold and copper concentrations in an aqueous electroplating bath. The speed and repeatability of the system make it well suited for in-process control. Data collection and reduction are automatic. The analysis requires less than 10 minutes from taking the sample to printing the gold and copper concentrations

  20. Analysis of point mutations in an ultraviolet-irradiated shuttle vector plasmid propagated in cells from Japanese xeroderma pigmentosum patients in complementation groups A and F

    Yagi, T.; Tatsumi-Miyajima, J.; Sato, M.; Kraemer, K.H.; Takebe, H.

    1991-01-01

    To assess the contribution to mutagenesis by human DNA repair defects, a UV-treated shuttle vector plasmid, pZ189, was passed through fibroblasts derived from Japanese xeroderma pigmentosum (XP) patients in two different DNA repair complementation groups (A and F). Patients with XP have clinical and cellular UV hypersensitivity, increased frequency of skin cancer, and defects in DNA repair. The XP DNA repair defects represented by complementation groups A (XP-A) and F (XP-F) are more common in Japan than in Europe or the United States. In comparison to results with DNA repair-proficient human cells (W138-VA13), UV-treated pZ189 passed through the XP-A [XP2OS(SV)] or XP-F [XP2YO(SV)] cells showed fewer surviving plasmids (XP-A less than XP-F) and a higher frequency of mutated plasmids (XP-A greater than XP-F). Base sequence analysis of more than 200 mutated plasmids showed the major type of base substitution mutation to be the G:C----A:T transition with all three cell lines. The XP-A and XP-F cells revealed a higher frequency of G:C----A:T transitions and a lower frequency of transversions among plasmids with single or tandem mutations and a lower frequency of plasmids with multiple point mutations compared to the normal line. The spectrum of mutations in pZ189 with the XP-A cells was similar to that with the XP-F cells. Seventy-six to 91% of the single base substitution mutations occurred at G:C base pairs in which the 5'-neighboring base of the cytosine was thymine or cytosine. These studies indicate that the DNA repair defects in Japanese XP patients in complementation groups A and F result in different frequencies of plasmid survival and mutagenesis but in similar types of mutagenic abnormalities despite marked differences in clinical features

  1. Analysis of root surface properties by fluorescence/Raman intensity ratio.

    Nakamura, Shino; Ando, Masahiro; Hamaguchi, Hiro-O; Yamamoto, Matsuo

    2017-11-01

    The aim of this study is to evaluate the existence of residual calculus on root surfaces by determining the fluorescence/Raman intensity ratio. Thirty-two extracted human teeth, partially covered with calculus on the root surface, were evaluated by using a portable Raman spectrophotometer, and a 785-nm, 100-mW laser was applied for fluorescence/Raman excitation. The collected spectra were normalized to the hydroxyapatite Raman band intensity at 960 cm -1 . Raman spectra were recorded from the same point after changing the focal distance of the laser and the target radiating angle. In seven teeth, the condition of calculus, cementum, and dentin were evaluated. In 25 teeth, we determined the fluorescence/Raman intensity ratio following three strokes of debridement. Raman spectra collected from the dentin, cementum, and calculus were different. After normalization, spectra values were constant. The fluorescence/Raman intensity ratio of calculus region showed significant differences compared to the cementum and dentin (p Raman intensity ratio decreased with calculus debridement. For this analysis, the delta value was defined as the difference between the values before and after three strokes, with the final 2 delta values close to zero, indicating a gradual asymptotic curve and the change in intensity ratio approximating that of individual constants. Fluorescence/Raman intensity ratio was effectively used to cancel the angle- and distance-dependent fluctuations of fluorescence collection efficiency during measurement. Changes in the fluorescence/Raman intensity ratio near zero suggested that cementum or dentin was exposed, and calculus removed.

  2. Chemical analysis by X-ray fluorescence, of niobium in high-strength plate steels

    Iozzi, F.B.; Dias, M.J.P.

    1981-01-01

    The use of X-ray fluorescence spectrometry in quantitative analysis of niobium in steels, as an alternative solution for optical emission spectrometry, in the rapid chemical control of steel fabrication by LD type converters, is presented. (M.C.K.) [pt

  3. X-ray fluorescence analysis of ancient and medieval brass artifacts from south Moravia

    Hložek, M.; Komoróczy, Balázs; Trojek, T.

    2012-01-01

    Roč. 7, č. 70 (2012), s. 1250-1253 ISSN 0969-8043 Institutional research plan: CEZ:AV0Z80010507 Institutional support: RVO:68081758 Keywords : x-ray fluorescence analysis * brass * Moravia Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 1.179, year: 2012

  4. X-ray fluorescence analysis study. Final report, December 1, 1970-December 31, 1977

    Kneip, T J; Laurer, G R

    1978-01-01

    This report has described the most significant experiments and the results obtained, during the development of a system for the detection and measurement of Pb in blood using radioisotope-excited x-ray fluorescence analysis, over the contract period. Briefly, the report described: detector selection; source selection; source-sample-detector geometry; sample preparation; system calibration; and separation technique. (PSB)

  5. Site-Specific Analysis of Protein Hydration Based on Unnatural Amino Acid Fluorescence

    Amaro, Mariana; Brezovský, J.; Kováčová, S.; Sýkora, Jan; Bednář, D.; Němec, V.; Lišková, V.; Kurumbang, N. P.; Beerens, K.; Chaloupková, R.; Paruch, K.; Hof, Martin; Damborský, J.

    2015-01-01

    Roč. 137, č. 15 (2015), s. 4988-4992 ISSN 0002-7863 R&D Projects: GA ČR GBP208/12/G016 Institutional support: RVO:61388955 Keywords : analysis * fluorescence * hydration of proteins Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 13.038, year: 2015

  6. Rapid analysis and exploration of fluorescence microscopy images.

    Pavie, Benjamin; Rajaram, Satwik; Ouyang, Austin; Altschuler, Jason M; Steininger, Robert J; Wu, Lani F; Altschuler, Steven J

    2014-03-19

    Despite rapid advances in high-throughput microscopy, quantitative image-based assays still pose significant challenges. While a variety of specialized image analysis tools are available, most traditional image-analysis-based workflows have steep learning curves (for fine tuning of analysis parameters) and result in long turnaround times between imaging and analysis. In particular, cell segmentation, the process of identifying individual cells in an image, is a major bottleneck in this regard. Here we present an alternate, cell-segmentation-free workflow based on PhenoRipper, an open-source software platform designed for the rapid analysis and exploration of microscopy images. The pipeline presented here is optimized for immunofluorescence microscopy images of cell cultures and requires minimal user intervention. Within half an hour, PhenoRipper can analyze data from a typical 96-well experiment and generate image profiles. Users can then visually explore their data, perform quality control on their experiment, ensure response to perturbations and check reproducibility of replicates. This facilitates a rapid feedback cycle between analysis and experiment, which is crucial during assay optimization. This protocol is useful not just as a first pass analysis for quality control, but also may be used as an end-to-end solution, especially for screening. The workflow described here scales to large data sets such as those generated by high-throughput screens, and has been shown to group experimental conditions by phenotype accurately over a wide range of biological systems. The PhenoBrowser interface provides an intuitive framework to explore the phenotypic space and relate image properties to biological annotations. Taken together, the protocol described here will lower the barriers to adopting quantitative analysis of image based screens.

  7. Elementary analysis by means of the x fluorescence and energy dispersion

    Jbeli, H.

    1988-10-01

    Three actualisation reports are shown, in the three first chapters, concerning the following subjects: x fluorescence principle, energy dispersive X ray spectroscopy and excitation spectrum characteristics. The matrice effects, the energy equivalence concept, and the correction methods of the interelement effects, related to a calibration curve, are discussed. For the last ones, it is shown that they are supplied to rough values. Quantitative analysis results are shown. A new possibility has been added to those of data processing program usually applied in quantitative analysis. In the second method applied in quantitative analysis, standard samples are used. In both methods an error appreciation analysis is carried out. It is shown that energy dispersive X fluorescence analysis can be applied to thin layers composition and thickness characterization [fr

  8. Segmentation and morphometric analysis of cells from fluorescence microscopy images of cytoskeletons.

    Ujihara, Yoshihiro; Nakamura, Masanori; Miyazaki, Hiroshi; Wada, Shigeo

    2013-01-01

    We developed a method to reconstruct cell geometry from confocal fluorescence microscopy images of the cytoskeleton. In the method, region growing was implemented twice. First, it was applied to the extracellular regions to differentiate them from intracellular noncytoskeletal regions, which both appear black in fluorescence microscopy imagery, and then to cell regions for cell identification. Analysis of morphological parameters revealed significant changes in cell shape associated with cytoskeleton disruption, which offered insight into the mechanical role of the cytoskeleton in maintaining cell shape. The proposed segmentation method is promising for investigations on cell morphological changes with respect to internal cytoskeletal structures.

  9. Gut fluorescence analysis of barnacle larvae: An approach to quantify the ingested food

    Gaonkar, C.A.; Anil, A.C.

    of Oceanography, Dona Paula, Goa, India A B S T R A C T Gut fluorescence analysis can provide a snapshot of ingested food and has been employed in the feeding studies of various organisms. In this study we standardised the gut fluorescence method utilising... naupliar instars and a pre-settling cyprid instar. The I instar nauplius is non-feeding and moults into II instar within a short interval of time. II to VI instars are phytoplanktivorus. Nauplii obtained from the adult broods of the barnacle Balanus...

  10. Application of synchrotron radiation to x-ray fluorescence analysis of trace elements

    Gordon, B.M.; Jones, K.W.; Hanson, A.L.

    1986-08-01

    The development of synchrotron radiation x-ray sources has provided the means to greatly extend the capabilities of x-ray fluorescence analysis for determinations of trace element concentrations. A brief description of synchrotron radiation properties provides a background for a discussion of the improved detection limits compared to existing x-ray fluorescence techniques. Calculated detection limits for x-ray microprobes with micrometer spatial resolutions are described and compared with experimental results beginning to appear from a number of laboratories. The current activities and future plans for a dedicated x-ray microprobe beam line at the National Synchrotron Light Source (NSLS) of Brookhaven National Laboratory are presented

  11. Chlorophyll fluorescence analysis: a guide to good practice and understanding some new applications.

    Murchie, E H; Lawson, T

    2013-10-01

    Chlorophyll fluorescence is a non-invasive measurement of photosystem II (PSII) activity and is a commonly used technique in plant physiology. The sensitivity of PSII activity to abiotic and biotic factors has made this a key technique not only for understanding the photosynthetic mechanisms but also as a broader indicator of how plants respond to environmental change. This, along with low cost and ease of collecting data, has resulted in the appearance of a large array of instrument types for measurement and calculated parameters which can be bewildering for the new user. Moreover, its accessibility can lead to misuse and misinterpretation when the underlying photosynthetic processes are not fully appreciated. This review is timely because it sits at a point of renewed interest in chlorophyll fluorescence where fast measurements of photosynthetic performance are now required for crop improvement purposes. Here we help the researcher make choices in terms of protocols using the equipment and expertise available, especially for field measurements. We start with a basic overview of the principles of fluorescence analysis and provide advice on best practice for taking pulse amplitude-modulated measurements. We also discuss a number of emerging techniques for contemporary crop and ecology research, where we see continual development and application of analytical techniques to meet the new challenges that have arisen in recent years. We end the review by briefly discussing the emerging area of monitoring fluorescence, chlorophyll fluorescence imaging, field phenotyping, and remote sensing of crops for yield and biomass enhancement.

  12. Tools for the quantitative analysis of sedimentation boundaries detected by fluorescence optical analytical ultracentrifugation.

    Huaying Zhao

    Full Text Available Fluorescence optical detection in sedimentation velocity analytical ultracentrifugation allows the study of macromolecules at nanomolar concentrations and below. This has significant promise, for example, for the study of systems of high-affinity protein interactions. Here we describe adaptations of the direct boundary modeling analysis approach implemented in the software SEDFIT that were developed to accommodate unique characteristics of the confocal fluorescence detection system. These include spatial gradients of signal intensity due to scanner movements out of the plane of rotation, temporal intensity drifts due to instability of the laser and fluorophores, and masking of the finite excitation and detection cone by the sample holder. In an extensive series of experiments with enhanced green fluorescent protein ranging from low nanomolar to low micromolar concentrations, we show that the experimental data provide sufficient information to determine the parameters required for first-order approximation of the impact of these effects on the recorded data. Systematic deviations of fluorescence optical sedimentation velocity data analyzed using conventional sedimentation models developed for absorbance and interference optics are largely removed after these adaptations, resulting in excellent fits that highlight the high precision of fluorescence sedimentation velocity data, thus allowing a more detailed quantitative interpretation of the signal boundaries that is otherwise not possible for this system.

  13. Fluorescence suppression using wavelength modulated Raman spectroscopy in fiber-probe-based tissue analysis.

    Praveen, Bavishna B; Ashok, Praveen C; Mazilu, Michael; Riches, Andrew; Herrington, Simon; Dholakia, Kishan

    2012-07-01

    In the field of biomedical optics, Raman spectroscopy is a powerful tool for probing the chemical composition of biological samples. In particular, fiber Raman probes play a crucial role for in vivo and ex vivo tissue analysis. However, the high-fluorescence background typically contributed by the auto fluorescence from both a tissue sample and the fiber-probe interferes strongly with the relatively weak Raman signal. Here we demonstrate the implementation of wavelength-modulated Raman spectroscopy (WMRS) to suppress the fluorescence background while analyzing tissues using fiber Raman probes. We have observed a significant signal-to-noise ratio enhancement in the Raman bands of bone tissue, which have a relatively high fluorescence background. Implementation of WMRS in fiber-probe-based bone tissue study yielded usable Raman spectra in a relatively short acquisition time (∼30  s), notably without any special sample preparation stage. Finally, we have validated its capability to suppress fluorescence on other tissue samples such as adipose tissue derived from four different species.

  14. Analysis of eight argonne premium coal samples by X-ray fluorescence spectrometry

    Evans, J.R.; Sellers, G.A.; Johnson, R.G.; Vivit, D.V.; Kent, J.

    1990-01-01

    X-ray fluorescence spectrometric methods were used in the analysis of eight Argonne Premium Coal Samples. Trace elements (Cr, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, La, and Ce) in coal ash were determined by energy-dispersive X-ray fluorescence spectrometry; major elements (Na, Mg, Al, Si, P, S, K, Ca, Ti, Mn, and Fe) in coal ash and trace elements (Cl and P) in whole coal were determined by wavelength-dispersive X-ray fluorescence spectrometry. The results of this study will be used in a geochemical database compiled for these materials from various analytical techniques. The experimental XRF methods and procedures used to determine these major and trace elements are described.

  15. Fluorescence decay data analysis correcting for detector pulse pile-up at very high count rates

    Patting, Matthias; Reisch, Paja; Sackrow, Marcus; Dowler, Rhys; Koenig, Marcelle; Wahl, Michael

    2018-03-01

    Using time-correlated single photon counting for the purpose of fluorescence lifetime measurements is usually limited in speed due to pile-up. With modern instrumentation, this limitation can be lifted significantly, but some artifacts due to frequent merging of closely spaced detector pulses (detector pulse pile-up) remain an issue to be addressed. We propose a data analysis method correcting for this type of artifact and the resulting systematic errors. It physically models the photon losses due to detector pulse pile-up and incorporates the loss in the decay fit model employed to obtain fluorescence lifetimes and relative amplitudes of the decay components. Comparison of results with and without this correction shows a significant reduction of systematic errors at count rates approaching the excitation rate. This allows quantitatively accurate fluorescence lifetime imaging at very high frame rates.

  16. Precision analysis for standard deviation measurements of immobile single fluorescent molecule images.

    DeSantis, Michael C; DeCenzo, Shawn H; Li, Je-Luen; Wang, Y M

    2010-03-29

    Standard deviation measurements of intensity profiles of stationary single fluorescent molecules are useful for studying axial localization, molecular orientation, and a fluorescence imaging system's spatial resolution. Here we report on the analysis of the precision of standard deviation measurements of intensity profiles of single fluorescent molecules imaged using an EMCCD camera.We have developed an analytical expression for the standard deviation measurement error of a single image which is a function of the total number of detected photons, the background photon noise, and the camera pixel size. The theoretical results agree well with the experimental, simulation, and numerical integration results. Using this expression, we show that single-molecule standard deviation measurements offer nanometer precision for a large range of experimental parameters.

  17. Analysis of archaeological ceramics by total-reflection X-ray fluorescence: Quantitative approaches

    Fernandez-Ruiz, R.; Garcia-Heras, M.

    2008-01-01

    This paper reports the quantitative methodologies developed for the compositional characterization of archaeological ceramics by total-reflection X-ray fluorescence at two levels. A first quantitative level which comprises an acid leaching procedure, and a second selective level, which seeks to increase the number of detectable elements by eliminating the iron present in the acid leaching procedure. Total-reflection X-ray fluorescence spectrometry has been compared, at a quantitative level, with Instrumental Neutron Activation Analysis in order to test its applicability to the study of this kind of materials. The combination of a solid chemical homogenization procedure previously reported with the quantitative methodologies here presented allows the total-reflection X-ray fluorescence to analyze 29 elements with acceptable analytical recoveries and accuracies

  18. Visualizing the dental biofilm matrix by means of fluorescence lectin-binding analysis

    Tawakoli, Pune Nina; Neu, Thomas R; Busck, Mette Marie

    2017-01-01

    lectins to visualize and quantify extracellular glycoconjugates in dental biofilms. Lectin binding was screened on pooled supragingival biofilm samples collected from 76 subjects using confocal microscopy. FLBA was then performed with 10 selected lectins on biofilms grown in situ for 48 h in the absence......The extracellular matrix is a poorly studied, yet important component of dental biofilms. Fluorescence lectin-binding analysis (FLBA) is a powerful tool to characterize glycoconjugates in the biofilm matrix. This study aimed to systematically investigate the ability of 75 fluorescently labeled......-biofilms: Aleuria aurantia (AAL), Calystega sepiem (Calsepa), Lycopersicon esculentum (LEA), Morniga-G (MNA-G) and Helix pomatia (HPA). No significant correlation between the binding of specific lectins and bacterial composition was found. Fluorescently labeled lectins enable the visualization of glycoconjugates...

  19. Analysis of archaeological ceramics by total-reflection X-ray fluorescence: Quantitative approaches

    Fernandez-Ruiz, R. [Servicio Interdepartamental de Investigacion, Facultad de Ciencias, Universidad Autonoma de Madrid, Modulo C-9, Laboratorio de TXRF, Crta. Colmenar, Km 15, Cantoblanco, E-28049, Madrid (Spain)], E-mail: ramon.fernandez@uam.es; Garcia-Heras, M. [Grupo de Arqueometria de Vidrios y Materiales Ceramicos, Instituto de Historia, Centro de Ciencias Humanas y Sociales, CSIC, C/ Albasanz, 26-28, 28037 Madrid (Spain)

    2008-09-15

    This paper reports the quantitative methodologies developed for the compositional characterization of archaeological ceramics by total-reflection X-ray fluorescence at two levels. A first quantitative level which comprises an acid leaching procedure, and a second selective level, which seeks to increase the number of detectable elements by eliminating the iron present in the acid leaching procedure. Total-reflection X-ray fluorescence spectrometry has been compared, at a quantitative level, with Instrumental Neutron Activation Analysis in order to test its applicability to the study of this kind of materials. The combination of a solid chemical homogenization procedure previously reported with the quantitative methodologies here presented allows the total-reflection X-ray fluorescence to analyze 29 elements with acceptable analytical recoveries and accuracies.

  20. Analysis of Cell Movement by Simultaneous Quantification of Local Membrane Displacement and Fluorescent Intensities Using Quimp2

    Bosgraaf, Leonard; van Haastert, Peter J. M.; Bretschneider, Till

    The use of fluorescent markers in living cells has increased dramatically in the recent years. The quantitative analysis of the images requires specific analysis software. Previously, the program Quimp was launched for quantitating fluorescent intensities at the membrane or the cortex of the cell.

  1. A dated phylogeny complements macroecological analysis to explain the diversity patterns in Geonoma (Arecaceae)

    Roncal, Julissa; Overgaard, Anne Blach; Borchsenius, Finn

    2011-01-01

    pattern. To test for a time-for-diversification effect, we correlated four different species richness measures with the diversification time of the earliest large lineage that is characteristic of each cluster. In support of this hypothesis, we found that geographic areas with higher richness contained...... coherent floristic clusters. We then evaluated the extent to which the spatial variation in species composition reflects present-day environmental variation vs. nonenvironmental spatial effects, as expected if the pattern reflects historical biogeography. We also examined the degree of geographic structure...... in the Geonoma phylogeny. Finally, we used a dated phylogeny to assess whether species richness within the floristic clusters was constrained by a specific historical biogeographic driver, namely time-for-diversification. A cluster analysis identified six spatially coherent floristic clusters, four of which were...

  2. Monitoring organic loading to swimming pools by fluorescence excitation–emission matrix with parallel factor analysis (PARAFAC)

    Seredynska-Sobecka, Bozena; Stedmon, Colin; Boe-Hansen, Rasmus

    2011-01-01

    Fluorescence Excitation–Emission Matrix spectroscopy combined with parallel factor analysis was employed to monitor water quality and organic contamination in swimming pools. The fluorescence signal of the swimming pool organic matter was low but increased slightly through the day. The analysis...... revealed that the organic matter fluorescence was characterised by five different components, one of which was unique to swimming pool organic matter and one which was specific to organic contamination. The latter component had emission peaks at 420nm and was found to be a sensitive indicator of organic...... loading in swimming pool water. The fluorescence at 420nm gradually increased during opening hours and represented material accumulating through the day....

  3. Analysis of environmental samples by roentgen fluorescence spectroscopy

    Hroncova, E.; Ladomersky, J.

    2004-01-01

    We can use it to analyse nearly all elements of solid and liquid samples. The possibility of analysing solid samples in compact shape, in powder or either under shape of fine layers shortens appreciably the total time of analysis, that is in addition to its no destructiveness, the main reason of as a XRF favourite method. (authors)

  4. Quantitative analysis of essential oils of Thymus daenensis using laser-induced fluorescence and Raman spectroscopy.

    Khoshroo, H; Khadem, H; Bahreini, M; Tavassoli, S H; Hadian, J

    2015-11-10

    Laser-induced fluorescence and Raman spectroscopy are used for the investigation of different genotypes of Thymus daenensis native to the Ilam province of Iran. Different genotypes of T. daenensis essential oils, labeled T1 through T7, possess slight differences with regard to the composition of the thymol. The gas chromatography-mass spectrometry (GC-MS) method is performed to determine the concentration of each constituent as a reference method. The Raman spectra of different concentrations of pure thymol dissolved in hexane as standard samples are obtained via a laboratory prototype Raman spectroscopy setup for the calculation of the calibration curve. The regression coefficient and limit of detection are calculated. The possibility of the differentiation of different genotypes of T. daenensis is also examined by laser-induced fluorescence spectroscopy, although we do not know the exact amounts of their components. All the fluorescence spectral information is used jointly by cluster analysis to differentiate between 7 genotypes. Our results demonstrate the acceptable precision of Raman spectroscopy with GC-MS and corroborate the capacity of Raman spectroscopy in applications in the quantitative analysis field. Furthermore, the cluster analysis results show that laser-induced fluorescence spectroscopy is an acceptable technique for the rapid classification of different genotypes of T. daenensis without having any previous information of their exact amount of constituents. So, the ability to rapidly and nondestructively differentiate between genotypes makes it possible to efficiently select high-quality herbs from many samples.

  5. Peripheral Artery Disease and Continuous Flow Left Ventricle Assist Device: An Engaging Complement Analysis May Help to Guide Treatment.

    Falletta, Calogero; Pasta, Salvatore; Raffa, Giuseppe Maria; Crinò, Francesca; Sciacca, Sergio; Clemenza, Francesco

    2018-02-13

    Use of continuous flow left ventricle assist device (CF-LVAD) in advanced heart failure (HF) patients results in clinically relevant improvements in survival, functional capacity, and quality of life. Peripheral artery disease (PAD) can occur in patients with CF-LVAD due to the high rate of concomitance between risk factors for atherosclerosis and HF. Diagnosis of PAD can be difficult in the specific setting of a patient supported by this kind of device because of the marked alteration in waveform morphology and velocity created by the artificial physiology of an LVAD. We report the case of a 53-year-old man with HF secondary to ischemic cardiomyopathy supported by the HeartWare HVAD as bridge to transplant, who after the implant developed symptoms suggestive of PAD. We describe additional computational flow analysis for the study of PAD-related hemodynamic disturbances induced by a CF-LVAD. Flow simulations enhance the information of clinical image data, and may have an application in clinical investigations of the risk of hemodynamic disturbances induced by LVAD implantation. © 2018 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  6. Quantitative analysis of fluorescence lifetime measurements of the macula using the fluorescence lifetime imaging ophthalmoscope in healthy subjects.

    Dysli, Chantal; Quellec, Gwénolé; Abegg, Mathias; Menke, Marcel N; Wolf-Schnurrbusch, Ute; Kowal, Jens; Blatz, Johannes; La Schiazza, Olivier; Leichtle, Alexander B; Wolf, Sebastian; Zinkernagel, Martin S

    2014-04-03

    Fundus autofluorescence (FAF) cannot only be characterized by the intensity or the emission spectrum, but also by its lifetime. As the lifetime of a fluorescent molecule is sensitive to its local microenvironment, this technique may provide more information than fundus autofluorescence imaging. We report here the characteristics and repeatability of FAF lifetime measurements of the human macula using a new fluorescence lifetime imaging ophthalmoscope (FLIO). A total of 31 healthy phakic subjects were included in this study with an age range from 22 to 61 years. For image acquisition, a fluorescence lifetime ophthalmoscope based on a Heidelberg Engineering Spectralis system was used. Fluorescence lifetime maps of the retina were recorded in a short- (498-560 nm) and a long- (560-720 nm) spectral channel. For quantification of fluorescence lifetimes a standard ETDRS grid was used. Mean fluorescence lifetimes were shortest in the fovea, with 208 picoseconds for the short-spectral channel and 239 picoseconds for the long-spectral channel, respectively. Fluorescence lifetimes increased from the central area to the outer ring of the ETDRS grid. The test-retest reliability of FLIO was very high for all ETDRS areas (Spearman's ρ = 0.80 for the short- and 0.97 for the long-spectral channel, P macula in healthy subjects. By using a custom-built software, we were able to quantify fluorescence lifetimes within the ETDRS grid. Establishing a clinically accessible standard against which to measure FAF lifetimes within the retina is a prerequisite for future studies in retinal disease.

  7. Material properties in complement activation

    Moghimi, S. Moein; Andersen, Alina Joukainen; Ahmadvand, Davoud

    2011-01-01

    activation differently and through different sensing molecules and initiation pathways. The importance of material properties in triggering complement is considered and mechanistic aspects discussed. Mechanistic understanding of complement events could provide rational approaches for improved material design...

  8. Single particle transfer for quantitative analysis with total-reflection X-ray fluorescence spectrometry

    Esaka, Fumitaka; Esaka, Konomi T.; Magara, Masaaki; Sakurai, Satoshi; Usuda, Shigekazu; Watanabe, Kazuo

    2006-01-01

    The technique of single particle transfer was applied to quantitative analysis with total-reflection X-ray fluorescence (TXRF) spectrometry. The technique was evaluated by performing quantitative analysis of individual Cu particles with diameters between 3.9 and 13.2 μm. The direct quantitative analysis of the Cu particle transferred onto a Si carrier gave a discrepancy between measured and calculated Cu amounts due to the absorption effects of incident and fluorescent X-rays within the particle. By the correction for the absorption effects, the Cu amounts in individual particles could be determined with the deviation within 10.5%. When the Cu particles were dissolved with HNO 3 solution prior to the TXRF analysis, the deviation was improved to be within 3.8%. In this case, no correction for the absorption effects was needed for quantification

  9. Determination of small amounts of aluminum in iron and steel by x-ray fluorescence analysis

    Ito, Minao; Sato, Shoki; Narita, Masanao

    1981-01-01

    The accuracy of X-ray fluorescence analysis for determining aluminum in steel is generally poor when the aluminum content is below 0.1%. In this study, it is confirmed that the existence of inhomogeneous acid-insoluble aluminum causes the poor accuracy of X-ray fluorescence analysis. The accuracy can be improved by adding granular ferro-zirconium to molten steel when sampling. By using this method, the accuracy of determining aluminum was 0.0024% for low alloy steels and 0.0022% for stainless steels as the standard deviation obtained for a series of differences between an analytical result and a standard value. Corrections for overlapping of the chromium spectrum, and for absorption and enhancement effects of co-existent elements are not necessary for the analysis of low alloy steels, whereas these corrections are necessary for the analysis of stainless steels. (author)

  10. Sample analysis using gamma ray induced fluorescent X-ray emission

    Sood, B S; Allawadhi, K L; Gandhi, R; Batra, O P; Singh, N [Punjabi Univ., Patiala (India). Nuclear Science Labs.

    1983-01-01

    A non-destructive method for the analysis of materials using gamma ray-induced fluorescent x-ray emission has been developed. In this method, special preparation of very thin samples in which the absorption of the incident gamma rays and the emitted fluorescent x-rays is negligible, is not needed, and the absorption correction is determined experimentally. A suitable choice of the incident gamma ray energies is made to minimise enhancement effects through selective photoionization of the elements in the sample. The method is applied to the analysis of a typical sample of the soldering material using 279 keV and 59.5 keV gamma rays from /sup 203/Hg and /sup 241/Am radioactive sources respectively. The results of the analysis are found to agree well with those obtained from the chemical analysis.

  11. The determination of lanthanum and lanthanide elements by means of X-ray fluorescence analysis

    Kuelcue, N.

    1982-01-01

    The quantitative analysis of all lanthanide elements (except Pm) was carried out concurrently using X-ray fluorescence analysis. By choice of suitable preparative methods (thin layer samples prepared by pipetting solutions onto filter paper) and use of an internal standard (Sr) it was possible to obtain linear calibration curves up to high concentrations in the solution (85 g/l) and to suppress disturbances caused by absorption and secondary fluorescence. A correction procedure was developed for reflection superimpositions in the L-spectra of the lanthanide elements which, through selection of the most favourable reflections for analysis, permitted concurrent determination of all 14 elements. Main and secondary constitutents can be analysed whereas enrichment is required for trace analysis. Under routine usage the actual limits of detection range from 3 to 17 μg/cm 2 or alternatively 0.3 to 1.7 mg/ml. (orig.) [de

  12. Scoria analysis by X-ray fluorescence with briquet

    Silva, G.R. da; Albert, P.E.

    1987-01-01

    The sample of scoria is triturated, using boric acid as agglomerative. The briquets are analyzed by X-ray quantometry, establishing the proportions of SiO 2 , P 2 O 5 , S, Cr 2 O 3 , V 2 O 5 , TiO 2 , Al 2 O 3 , Mg O, Ca O, FeO and their basicity. The calibration curves are prepared with standard scoria samples, by chemical analysis. (C.G.C.) [pt

  13. Development of unified X-ray fluorescent analysis to determine rhenium content in multicomponent oxide compositions

    Drobot, D.V.; Belyaev, A.V.; Kutvitskij, V.A.; Rysev, A.P.

    1999-01-01

    A procedure to prepare rhenium-containing glass-like specimens on the basis of bismuth and boron oxides is proposed. The glasses produced are studied by X-ray fluorescent analysis and routine spectrometric thiocyanate analysis. The results make it possible to determine rhenium in oxide mixtures in the range of its content 0.01 - 10% with S r = 0.03 [ru

  14. Multielemental analysis of surface sediments in Havana bay (Cuba) using X-ray fluorescence

    Gelen, A.; Corrales, Y.; Lopez, N.; Manso Guevara, M. V.; Casanova, A. O.; Alessandro, K. D'; Diaz, O.; Espen, P. Van; Beltran, J.; Soto, J.

    2006-01-01

    Multielemental Analysis was performed in Superficial Sediments in Havana Bay. Twenty one samples were analysed by Dispersive Energy X- Ray Fluorescence using an spectrometer based on Si (Li) semiconductor detector an a 109 Cd source. The results showed a similar behaviour in the levels of contamination related with neutron activation analysis. The data suggest that an anthropogenic input into the bay from domestic sewage and industries occurred. (Full text)

  15. Analysis of noble metal on automotive exhaust catalysts by radioisotope-induce x-ray fluorescence

    Elgart, M.F.

    1976-01-01

    A technique was developed for the in-situ analysis of noble metals deposited on monolithic automotive exhaust catalysts. This technique is based on radioisotope-induced x-ray fluorescence, and provides a detailed picture of the distribution of palladium and platinum on catalyst samples. The experimental results for the cross section of a monolithic exhaust catalyst, analyzed in increments of 0.2 cm 3 , are compared with analyses for palladium and platinum obtained by instrumental neutron activation analysis

  16. Embryonic lineage analysis using three-dimensional, time-lapse in-vivo fluorescent microscopy

    Minden, Jonathan; Kam, Zvi; Agard, David A.; Sedat, John W.; Alberts, Bruce

    1990-08-01

    Drosophila melanogaster has become one of the most extensively studied organisms because of its amenability to genetic analysis. Unfortunately, the biochemistry and cell biology ofDrosophila has lagged behind. To this end we have been microinjecting fluorescently labelled proteins into the living embryo and observing the behavior of these proteins to determine their role in the cell cycle and development. Imaging of these fluorescent probes is an extremely important element to this form of analysis. We have taken advantage of the sensitivity and well behaved characteristics of the charge coupled device (CCD) camera in conjunction with digital image enhancement schemes to produce highly accurate images of these fluorescent probes in vivo. One of our major goals is to produce a detailed map of cell fate so that we can understand how fate is determined and maintained. In order produce such a detailed map, protocols for following the movements and mitotic behavior of a large number of cells in three dimensions over relatively long periods of time were developed. We will present our results using fluorescently labelled histone proteins as a marker for nuclear location1. In addition, we will also present our initial results using a photoactivatable analog of fluorescein to mark single cells so that their long range fate can be unambiguously determined.

  17. Total-reflection X-ray fluorescence analysis of Austrian wine

    Gruber, X. [Atominstitut der Osterreichischen Universitaeten, 1020 Vienna (Austria); Kregsamer, P. [Atominstitut der Osterreichischen Universitaeten, 1020 Vienna (Austria); Wobrauschek, P. [Atominstitut der Osterreichischen Universitaeten, 1020 Vienna (Austria); Streli, C. [Atominstitut der Osterreichischen Universitaeten, 1020 Vienna (Austria)]. E-mail: streli@ati.ac.at

    2006-11-15

    The concentration of major, minor and trace elements in Austrian wine was determined by total-reflection X-ray fluorescence using gallium as internal standard. A multi-elemental analysis was possible by pipetting 6 {mu}l of wine directly on the reflector and drying. Total-reflection X-ray fluorescence analysis was performed with Atomika EXTRA II A (Cameca) X-rays from a Mo tube with a high-energy cut-off at 20 keV in total-reflection geometry. The results showed that it was possible to identify only by the elemental analysis as fingerprint the vineyards and year of vintage among 11 different wines.

  18. Total-reflection X-ray fluorescence analysis of Austrian wine

    Gruber, X.; Kregsamer, P.; Wobrauschek, P.; Streli, C.

    2006-01-01

    The concentration of major, minor and trace elements in Austrian wine was determined by total-reflection X-ray fluorescence using gallium as internal standard. A multi-elemental analysis was possible by pipetting 6 μl of wine directly on the reflector and drying. Total-reflection X-ray fluorescence analysis was performed with Atomika EXTRA II A (Cameca) X-rays from a Mo tube with a high-energy cut-off at 20 keV in total-reflection geometry. The results showed that it was possible to identify only by the elemental analysis as fingerprint the vineyards and year of vintage among 11 different wines

  19. Fluorescence correlation spectroscopy analysis for accurate determination of proportion of doubly labeled DNA in fluorescent DNA pool for quantitative biochemical assays.

    Hou, Sen; Sun, Lili; Wieczorek, Stefan A; Kalwarczyk, Tomasz; Kaminski, Tomasz S; Holyst, Robert

    2014-01-15

    Fluorescent double-stranded DNA (dsDNA) molecules labeled at both ends are commonly produced by annealing of complementary single-stranded DNA (ssDNA) molecules, labeled with fluorescent dyes at the same (3' or 5') end. Because the labeling efficiency of ssDNA is smaller than 100%, the resulting dsDNA have two, one or are without a dye. Existing methods are insufficient to measure the percentage of the doubly-labeled dsDNA component in the fluorescent DNA sample and it is even difficult to distinguish the doubly-labeled DNA component from the singly-labeled component. Accurate measurement of the percentage of such doubly labeled dsDNA component is a critical prerequisite for quantitative biochemical measurements, which has puzzled scientists for decades. We established a fluorescence correlation spectroscopy (FCS) system to measure the percentage of doubly labeled dsDNA (PDL) in the total fluorescent dsDNA pool. The method is based on comparative analysis of the given sample and a reference dsDNA sample prepared by adding certain amount of unlabeled ssDNA into the original ssDNA solution. From FCS autocorrelation functions, we obtain the number of fluorescent dsDNA molecules in the focal volume of the confocal microscope and PDL. We also calculate the labeling efficiency of ssDNA. The method requires minimal amount of material. The samples have the concentration of DNA in the nano-molar/L range and the volume of tens of microliters. We verify our method by using restriction enzyme Hind III to cleave the fluorescent dsDNA. The kinetics of the reaction depends strongly on PDL, a critical parameter for quantitative biochemical measurements. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Development of suitable plastic standards for X-ray fluorescence analysis

    Mans, Christian [University of Applied Sciences Muenster, Department of Chemical Engineering, Advanced Analytical Chemistry, Stegerwaldstr. 39, 48565 Steinfurt (Germany)], E-mail: c.mans@fh-muenster.de; Hanning, Stephanie [University of Applied Sciences Muenster, Department of Chemical Engineering, Advanced Analytical Chemistry, Stegerwaldstr. 39, 48565 Steinfurt (Germany)], E-mail: hanning@fh-muenster.de; Simons, Christoph [University of Applied Sciences Muenster, Department of Chemical Engineering, Advanced Analytical Chemistry, Stegerwaldstr. 39, 48565 Steinfurt (Germany)], E-mail: simons@fh-muenster.de; Wegner, Anne [University of Applied Sciences Muenster, Department of Chemical Engineering, Advanced Analytical Chemistry, Stegerwaldstr. 39, 48565 Steinfurt (Germany)], E-mail: awegner@fh-muenster.de; Janssen, Anton [University of Applied Sciences Muenster, Department of Chemical Engineering, Advanced Analytical Chemistry, Stegerwaldstr. 39, 48565 Steinfurt (Germany)], E-mail: janssena@fh-muenster.de; Kreyenschmidt, Martin [University of Applied Sciences Muenster, Department of Chemical Engineering, Advanced Analytical Chemistry, Stegerwaldstr. 39, 48565 Steinfurt (Germany)], E-mail: martin.kreyenschmidt@fh-muenster.de

    2007-02-15

    For the adoption of the EU directive 'Restriction on use of certain Hazardous Substances' and 'Waste Electrical and Electronic Equipment' using X-ray fluorescence analysis suitable standard materials are required. Plastic standards based on acrylonitrile-butadiene-styrene terpolymer, containing the regulated elements Br, Cd, Cr, Hg and Pb were developed and produced as granulates and solid bodies. The calibration materials were not generated as a dilution from one master batch but rather the element concentrations were distributed over nine independent calibration samples. This was necessary to enable inter-elemental corrections and empirical constant mass absorption coefficients. The produced standard materials are characterized by a homogenous element distribution, which is more than sufficient for X-ray fluorescence analysis. Concentrations for all elements except for Br could be determined by Inductively Coupled Plasma Atomic Emission Spectroscopy after microwave assisted digestion. The concentration of Br was determined by use of Neutron Activation Analysis at Hahn-Meitner-Institute in Berlin, Germany. The correlation of the X-ray fluorescence analysis measurements with the values determined using Inductively Coupled Plasma Atomic Emission Spectroscopy and Neutron Activation Analysis showed a very good linearity.

  1. Quantitative analysis of dynamic association in live biological fluorescent samples.

    Pekka Ruusuvuori

    Full Text Available Determining vesicle localization and association in live microscopy may be challenging due to non-simultaneous imaging of rapidly moving objects with two excitation channels. Besides errors due to movement of objects, imaging may also introduce shifting between the image channels, and traditional colocalization methods cannot handle such situations. Our approach to quantifying the association between tagged proteins is to use an object-based method where the exact match of object locations is not assumed. Point-pattern matching provides a measure of correspondence between two point-sets under various changes between the sets. Thus, it can be used for robust quantitative analysis of vesicle association between image channels. Results for a large set of synthetic images shows that the novel association method based on point-pattern matching demonstrates robust capability to detect association of closely located vesicles in live cell-microscopy where traditional colocalization methods fail to produce results. In addition, the method outperforms compared Iterated Closest Points registration method. Results for fixed and live experimental data shows the association method to perform comparably to traditional methods in colocalization studies for fixed cells and to perform favorably in association studies for live cells.

  2. Sorting fluorescent nanocrystals with DNA

    Gerion, Daniele; Parak, Wolfgang J.; Williams, Shara C.; Zanchet, Daniela; Micheel, Christine M.; Alivisatos, A. Paul

    2001-12-10

    Semiconductor nanocrystals with narrow and tunable fluorescence are covalently linked to oligonucleotides. These biocompounds retain the properties of both nanocrystals and DNA. Therefore, different sequences of DNA can be coded with nanocrystals and still preserve their ability to hybridize to their complements. We report the case where four different sequences of DNA are linked to four nanocrystal samples having different colors of emission in the range of 530-640 nm. When the DNA-nanocrystal conjugates are mixed together, it is possible to sort each type of nanoparticle using hybridization on a defined micrometer -size surface containing the complementary oligonucleotide. Detection of sorting requires only a single excitation source and an epifluorescence microscope. The possibility of directing fluorescent nanocrystals towards specific biological targets and detecting them, combined with their superior photo-stability compared to organic dyes, opens the way to improved biolabeling experiments, such as gene mapping on a nanometer scale or multicolor microarray analysis.

  3. FluoRender: joint freehand segmentation and visualization for many-channel fluorescence data analysis.

    Wan, Yong; Otsuna, Hideo; Holman, Holly A; Bagley, Brig; Ito, Masayoshi; Lewis, A Kelsey; Colasanto, Mary; Kardon, Gabrielle; Ito, Kei; Hansen, Charles

    2017-05-26

    Image segmentation and registration techniques have enabled biologists to place large amounts of volume data from fluorescence microscopy, morphed three-dimensionally, onto a common spatial frame. Existing tools built on volume visualization pipelines for single channel or red-green-blue (RGB) channels have become inadequate for the new challenges of fluorescence microscopy. For a three-dimensional atlas of the insect nervous system, hundreds of volume channels are rendered simultaneously, whereas fluorescence intensity values from each channel need to be preserved for versatile adjustment and analysis. Although several existing tools have incorporated support of multichannel data using various strategies, the lack of a flexible design has made true many-channel visualization and analysis unavailable. The most common practice for many-channel volume data presentation is still converting and rendering pseudosurfaces, which are inaccurate for both qualitative and quantitative evaluations. Here, we present an alternative design strategy that accommodates the visualization and analysis of about 100 volume channels, each of which can be interactively adjusted, selected, and segmented using freehand tools. Our multichannel visualization includes a multilevel streaming pipeline plus a triple-buffer compositing technique. Our method also preserves original fluorescence intensity values on graphics hardware, a crucial feature that allows graphics-processing-unit (GPU)-based processing for interactive data analysis, such as freehand segmentation. We have implemented the design strategies as a thorough restructuring of our original tool, FluoRender. The redesign of FluoRender not only maintains the existing multichannel capabilities for a greatly extended number of volume channels, but also enables new analysis functions for many-channel data from emerging biomedical-imaging techniques.

  4. Data for analysis of mannose-6-phosphate glycans labeled with fluorescent tags.

    Kang, Ji-Yeon; Kwon, Ohsuk; Gil, Jin Young; Oh, Doo-Byoung

    2016-06-01

    Mannose-6-phosphate (M-6-P) glycan plays an important role in lysosomal targeting of most therapeutic enzymes for treatment of lysosomal storage diseases. This article provides data for the analysis of M-6-P glycans by high-performance liquid chromatography (HPLC) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The identities of M-6-P glycan peaks in HPLC profile were confirmed by measuring the masses of the collected peak eluates. The performances of three fluorescent tags (2-aminobenzoic acid [2-AA], 2-aminobenzamide [2-AB], and 3-(acetyl-amino)-6-aminoacridine [AA-Ac]) were compared focusing on the analysis of bi-phosphorylated glycan (containing two M-6-Ps). The bi-phosphorylated glycan analysis is highly affected by the attached fluorescent tag and the hydrophilicity of elution solvent used in HPLC. The data in this article is associated with the research article published in "Comparison of fluorescent tags for analysis of mannose-6-phosphate glycans" (Kang et al., 2016 [1]).

  5. Data for analysis of mannose-6-phosphate glycans labeled with fluorescent tags

    Ji-Yeon Kang

    2016-06-01

    Full Text Available Mannose-6-phosphate (M-6-P glycan plays an important role in lysosomal targeting of most therapeutic enzymes for treatment of lysosomal storage diseases. This article provides data for the analysis of M-6-P glycans by high-performance liquid chromatography (HPLC and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF mass spectrometry. The identities of M-6-P glycan peaks in HPLC profile were confirmed by measuring the masses of the collected peak eluates. The performances of three fluorescent tags (2-aminobenzoic acid [2-AA], 2-aminobenzamide [2-AB], and 3-(acetyl-amino-6-aminoacridine [AA-Ac] were compared focusing on the analysis of bi-phosphorylated glycan (containing two M-6-Ps. The bi-phosphorylated glycan analysis is highly affected by the attached fluorescent tag and the hydrophilicity of elution solvent used in HPLC. The data in this article is associated with the research article published in “Comparison of fluorescent tags for analysis of mannose-6-phosphate glycans” (Kang et al., 2016 [1].

  6. Segmentation-based retrospective shading correction in fluorescence microscopy E. coli images for quantitative analysis

    Mai, Fei; Chang, Chunqi; Liu, Wenqing; Xu, Weichao; Hung, Yeung S.

    2009-10-01

    Due to the inherent imperfections in the imaging process, fluorescence microscopy images often suffer from spurious intensity variations, which is usually referred to as intensity inhomogeneity, intensity non uniformity, shading or bias field. In this paper, a retrospective shading correction method for fluorescence microscopy Escherichia coli (E. Coli) images is proposed based on segmentation result. Segmentation and shading correction are coupled together, so we iteratively correct the shading effects based on segmentation result and refine the segmentation by segmenting the image after shading correction. A fluorescence microscopy E. Coli image can be segmented (based on its intensity value) into two classes: the background and the cells, where the intensity variation within each class is close to zero if there is no shading. Therefore, we make use of this characteristics to correct the shading in each iteration. Shading is mathematically modeled as a multiplicative component and an additive noise component. The additive component is removed by a denoising process, and the multiplicative component is estimated using a fast algorithm to minimize the intra-class intensity variation. We tested our method on synthetic images and real fluorescence E.coli images. It works well not only for visual inspection, but also for numerical evaluation. Our proposed method should be useful for further quantitative analysis especially for protein expression value comparison.

  7. Quantitative analysis of tear film fluorescence and discomfort during tear film instability and thinning.

    Begley, Carolyn; Simpson, Trefford; Liu, Haixia; Salvo, Eliza; Wu, Ziwei; Bradley, Arthur; Situ, Ping

    2013-04-12

    The purpose of this study was to test the association between tear film fluorescence changes during tear break-up (TBU) or thinning and the concurrent ocular sensory response. Sixteen subjects kept one eye open as long as possible (MBI), indicated their discomfort level continuously, and rated ocular sensations of irritation, stinging, burning, pricking, and cooling using visual analog scales (VAS). Fluorescence of the tear film was quantified by a pixel-based analysis of the median pixel intensity (PI), TBU, and percentage of dark pixels (DarkPix) over time. A cutoff of 5% TBU was used to divide subjects into either break-up (BU) or minimal break-up (BUmin) groups. Tear film fluorescence decreased (median PI) and the percentage of TBU and DarkPix increased in all trials, with the rate significantly greater in the BU than the BUmin group (Mann-Whitney U test, P film thinning best explains decreasing tear film fluorescence during trials. This was highly correlated with increasing ocular discomfort, suggesting that both tear film thinning and TBU stimulate underlying corneal nerves, although TBU produced more rapid stimulation. Slow increases in tear film hyperosmolarity may cause the gradual increase in discomfort during slow tear film thinning, whereas the sharp increases in discomfort during TBU suggest a more complex stimulus.

  8. Contribution to the analysis of light elements using x fluorescence excited by radio-elements

    Robert, A.

    1964-01-01

    In order to study the possibilities of using radioactive sources for the X-fluorescence analysis of light elements, the principle is given, after a brief description of X-fluorescence, of the excitation of this phenomenon by X, β and α emission from radio-elements. The operation and use of the proportional gas counter for X-ray detection is described. A device has been studied for analysing the elements of the 2. and 3. periods of the Mendeleev table. It makes it possible to excite the fluorescence with a radioactive source emitting X-rays or a particles; the X-ray fluorescence penetrates into a window-less proportional counter, this being made possible by the use of an auxiliary electric field in the neighbourhood of the sample. The gas detection pressure leading to the maximum detection yield is given. The spectra are given for the K α lines of 3. period elements excited by 55 Fe, 3 H/Zr and 210 Po sources; for the 2. period the K α spectra of carbon and of fluorine excited by the α particles of 210 Po. (author) [fr

  9. Comparative real-time kinetic analysis of human complement killing of Leishmania infantum promastigotes derived from axenic culture or from Phlebotomus perniciosus.

    Moreno, Inmaculada; Molina, Ricardo; Toraño, Alfredo; Laurin, Edurne; García, Esther; Domínguez, Mercedes

    2007-01-01

    Although Leishmania metacyclic promastigotes are generally considered resistant to human complement, studies of in vitro-cultured axenic stationary promastigotes using serum concentrations that approximate physiological plasma conditions indicate complement sensitivity. Natural Leishmania infection is caused by sand fly-inoculated promastigotes, whose complement resistance has not been analyzed systematically. We compared Leishmania susceptibility to human complement in L. infantum promastigotes derived from in vitro cultures and from sand flies. Phlebotomus perniciosus sand flies were fed with axenic promastigotes, L. infantum-infected U-937 cells, or spleen cells from L. infantum-infected hamsters. On selected days post-feeding, flies were dissected and promastigotes isolated; in addition, axenic promastigotes were obtained from culture at equivalent days of growth. In near-physiological serum concentration and temperature conditions, measurement of real-time kinetics of propidium iodide uptake showed that approximately 90% of axenic- and sand fly-derived promastigotes were rapidly killed by complement. We found no substantial differences between promastigotes from axenic culture, those isolated from flies on different post-feeding days, or those generated in flies fed with distinct inocula. The results indicate that Leishmania susceptibility to human complement is independent of promastigote developmental stage in the sand fly mid-gut and in axenic culture.

  10. Analysis of metals in organic compounds by energy dispersive X-ray fluorescence analysis

    Anjos, Marcelino J.; Lopes, Ricardo T.; Jesus, Edgar F.O. de

    2000-01-01

    Using energy dispersive X-ray fluorescence analysis with an X-ray tube filtered with Ti. It was possible to determine the concentration of the elements at ppm level of several elements: K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn As, Rb, Sr, Y, Zr, and Pb in two types of organic compound enough used in the agriculture: organic compound of urban garbage (Fertilurb) and aviary bed (birds manure). The experimental setup is composed of: x-ray tube (Oxford, 30 kV, 50 μA and W anode), an ORTEC Si-Li detector, with an energy resolution of about 180 eV at 5.9 keV and an ORTEC multichannel-analyser. The X-ray beam is quasi- monochromatic by using Ti filter. The samples were prepared in pellet form with superficial density in the range of 100 mg/cm 2 . The fundamental parameter method was used in order to verify the elemental concentration. The radiation transmission method was going used to the radiation absorption effects correction in the samples. (author)

  11. Rapid analysis of molybdenum contents in molybdenum master alloys by X-ray fluorescence technique

    Tongkong, P.

    1985-01-01

    Determination of molybdenum contents in molybdenum master alloy had been performed using energy dispersive x-ray fluorescence (EDX) technique where analysis were made via standard additions and calibration curves. Comparison of EDX technique with other analyzing techniques, i.e., wavelength dispersive x-ray fluorescence, neutron activation analysis and inductive coupled plasma spectrometry, showed consistency in the results. This technique was found to yield reliable results when molybdenum contents in master alloys were in the range of 13 to 50 percent using HPGe detector or proportional counter. When the required error was set at 1%, the minimum analyzing time was found to be 30 and 60 seconds for Fe-Mo master alloys with molybdenum content of 13.54 and 49.09 percent respectively. For Al-Mo master alloys, the minimum times required were 120 and 300 seconds with molybdenum content of 15.22 and 47.26 percent respectively

  12. Theoretical Influence Coefficients For X-Ray Fluorescence Analysis Of Alloys

    Okunade, I.O.

    2004-01-01

    The problem of quantifications in X-ray fluorescence analysis has over the years been narrowed down to matrix effects arising from the presence of other elements in the sample, which may either lead to the reduction or enhancement in the measured intensities of the analytic element. This paper describes a mathematical matrix correction method, which yield certain fundamental coefficients that account for the inter-element effects. The application of these influence coefficients in quantitative analysis however relies on the knowledge of pure element intensities of the analyse element, its mass absorption coefficients (for exciting and fluorescent radiation) of other elements in the sample that are responsible for the matrix effects. The quantification method using these coefficients are thereafter established for binary systems and further extended to multi-component systems such as ternary and quaternary alloys

  13. Hybrid Microfluidic Platform for Multifactorial Analysis Based on Electrical Impedance, Refractometry, Optical Absorption and Fluorescence

    Fábio M. Pereira

    2016-10-01

    Full Text Available This paper describes the development of a novel microfluidic platform for multifactorial analysis integrating four label-free detection methods: electrical impedance, refractometry, optical absorption and fluorescence. We present the rationale for the design and the details of the microfabrication of this multifactorial hybrid microfluidic chip. The structure of the platform consists of a three-dimensionally patterned polydimethylsiloxane top part attached to a bottom SU-8 epoxy-based negative photoresist part, where microelectrodes and optical fibers are incorporated to enable impedance and optical analysis. As a proof of concept, the chip functions have been tested and explored, enabling a diversity of applications: (i impedance-based identification of the size of micro beads, as well as counting and distinguishing of erythrocytes by their volume or membrane properties; (ii simultaneous determination of the refractive index and optical absorption properties of solutions; and (iii fluorescence-based bead counting.

  14. WellReader: a MATLAB program for the analysis of fluorescence and luminescence reporter gene data.

    Boyer, Frédéric; Besson, Bruno; Baptist, Guillaume; Izard, Jérôme; Pinel, Corinne; Ropers, Delphine; Geiselmann, Johannes; de Jong, Hidde

    2010-05-01

    Fluorescent and luminescent reporter gene systems in combination with automated microplate readers allow real-time monitoring of gene expression on the population level at high precision and sampling density. This generates large amounts of data for the analysis of which computer tools are missing to date. We have developed WellReader, a MATLAB program for the analysis of fluorescent and luminescent reporter gene data. WellReader allows the user to load the output files of microplate readers, remove outliers, correct for background effects and smooth and fit the data. Moreover, it computes biologically relevant quantities from the measured signals, notably promoter activities and protein concentrations, and compares the resulting expression profiles of different genes under different conditions. WellReader is available under a LGPL licence at http://prabi1.inrialpes.fr/trac/wellreader.

  15. Applications of total reflection X-ray fluorescence in multi-element analysis

    Michaelis, W.; Prange, A.; Knoth, J.

    1985-01-01

    Although Total Reflection X-Ray Fluorescence Analysis (TXRF) became available for practical applications and routine measurements only few years ago, the number of programmes that make use of this method is increasing rapidly. The scope of work is widespread over environmental research and monitoring, mineralogy, mineral exploration, oceanography, biology, medicine and biochemistry. The present paper gives a brief survey of these applications and summarizes some of them which are typical for quite different matrices. (orig.)

  16. Radioisotope induced X-ray fluorescence analysis of cereal grains and flour

    Toeroek, Sz.; Szoekefalvi-Nagy, Z.

    1982-06-01

    Radioisotope-induced X-ray fluorescence analysis is a rather simple and easy method for investigating ashed plant material. In order to reduce matrix effects thin samples of 2 mg/cm 2 are analysed to obtain a reasonable compromise between maximum sensitivity and the lowest possible absorption effects. Concentrations are determined by standard addition method. An accuracy of 6-8% can be achieved. As an application analytical results are given for whole grains of several sorts of wheat. (author)

  17. Energy dispersion X-ray fluorescence techniques in water pollution analysis

    Holynska, B.

    1980-01-01

    Advantages and limitations of energy dispersion X-ray fluorescence methods for analysis of pollutants in water are discussed. The necessary equipment for X-ray measurement of insoluble and dissolved trace metals in water is described. Different techniques of enrichment of trace metals are presented: ion exchange on selective Chelex-100 exchanger, precipitation with chelating agents DDTC and APDC, and adsorption on activated carbon. Some results obtained using different preconcentration methods for trace metals determination in different waters are presented. (author)

  18. Proteomic Analysis of Bovine Pregnancy-specific Serum Proteins by 2D Fluorescence Difference Gel Electrophoresis

    Lee, Jae Eun; Lee, Jae Young; Kim, Hong Rye; Shin, Hyun Young; Lin, Tao; Jin, Dong Il

    2015-01-01

    Two dimensional-fluorescence difference gel electrophoresis (2D DIGE) is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2...

  19. Multi-color fluorescent DNA analysis in an integrated optofluidic lab-on-a-chip

    Dongre, C.; van Weerd, J.; van Weeghel, R.; Martinez-Vazquez, R.; Osellame, R.; Cerullo, G.; Besselink, G.A.J.; van den Vlekkert, H.H.; Hoekstra, Hugo; Pollnau, Markus

    2010-01-01

    Sorting and sizing of DNA molecules within the human genome project has enabled the genetic mapping of various illnesses. By employing tiny lab-on-a-chip devices for such DNA analysis, integrated DNA sequencing and genetic diagnostics have become feasible. However, such diagnostic chips typically lack integrated sensing capability. We address this issue by combining microfluidic capillary electrophoresis with laser-induced fluorescence detection resulting in optofluidic integration towards an...

  20. Correction for interelement effect in X-Ray fluorescence analysis of trace elements in geological materials

    El-Behay, A.Z.; Attawiya, M.Y.; Khattab, F.M.

    1984-01-01

    In a trial to obtain accurate results from X-ray fluorescence technique for the analysis of trace elements in geological materials, two corrections were used for the obtained data, namely, correction for the observed x-ray intensities for absorption and/or enhancement effects due to the presence of other elements in the system and correction for spectral deconvolution to account for the overlapping lines. Significant improvement in the precision and accuracy was obtained and evaluated

  1. Determination of potassium concentration in organic samples by means of x-ray fluorescence analysis

    Soto Moran, R.L.; Szgedi, S.

    1993-01-01

    By means of x-ray fluorescence analysis and the inner standard method using KH 2 PO 4 as the added chemical compound, potassium concentration of roots, stems , leaf, flowers and grains from Quinua (Chenopodium Quinoa Willd). which was previously treated with a nitrogen ed fertilizers has been determined taking into account the increasing effect the average atomic number due to used standard. Experimental errors are lower than 10 %

  2. Total reflection X-ray fluorescence analysis with synchrotron radiation monochromatized by multilayer structures

    Rieder, R.; Wobrauschek, P.; Ladisich, W.; Streli, C.; Aiginger, H.; Garbe, S.; Gaul, G.; Knoechel, A.; Lechtenberg, F.

    1995-01-01

    To achieve lowest detection limits in total reflection X-ray fluorescence analysis (TXRF) synchrotron radiation has been monochromatized by a multilayer structure to obtain a relative broad energy band compared to Bragg single crystals for an efficient excitation. The energy has been set to 14 keV, 17.5 keV, 31 keV and about 55 keV. Detection limits of 20 fg and 150 fg have been achieved for Sr and Cd, respectively. ((orig.))

  3. SAVLOC, computer program for automatic control and analysis of X-ray fluorescence experiments

    Leonard, R. F.

    1977-01-01

    A program for a PDP-15 computer is presented which provides for control and analysis of trace element determinations by using X-ray fluorescence. The program simultaneously handles data accumulation for one sample and analysis of data from previous samples. Data accumulation consists of sample changing, timing, and data storage. Analysis requires the locating of peaks in X-ray spectra, determination of intensities of peaks, identification of origins of peaks, and determination of a real density of the element responsible for each peak. The program may be run in either a manual (supervised) mode or an automatic (unsupervised) mode.

  4. Fourier transform infrared and fluorescence spectroscopy for analysis of vegetable oils

    Nigri S.

    2013-09-01

    Full Text Available Fourier transform infrared (FTIR and fluorescence spectroscopy, combined with chemometric approaches have been developed to analysis of extra virgin olive oil adulterated with pomace olive oil. The measurements were made on pure vegetable oils: extra virgin oil, pomace olive oil and that adulterated with varying concentration of pomace olive oil. Today, the application of FTIR spectroscopy has increased in food studied, and particularly has become a powerful analytical tool in the study of edible oils and fats. The spectral regions where the variations were observed chosen for developing models and cross validation was used. The synchronous fluorescence spectrometry takes advantage of the hardware capability to vary both the excitation and emission wavelengths during the analysis with constant wavelength difference is maintained between the two. The region between 300 and 400 nm is attributed to the tocopherols and phenols, the derivatives of vitamin E are associated with the region 400–600 nm and the bands in the region of 600–700 nm are attributed to the chlorophyll and peophytin pigments. The results presented in this study suggest that FTIR and fluorescence may be a useful tool for analysis and detecting adulteration of extra virgin olive oil with pomace oil.

  5. Shark complement: an assessment.

    Smith, S L

    1998-12-01

    The classical (CCP) and alternative (ACP) pathways of complement activation have been established for the nurse shark (Ginglymostoma cirratum). The isolation of a cDNA clone encoding a mannan-binding protein-associated serine protease (MASP)-1-like protein from the Japanese dogfish (Triakis scyllia) suggests the presence of a lectin pathway. The CCP consists of six functionally distinct components: C1n, C2n, C3n, C4n, C8n and C9n, and is activated by immune complexes in the presence of Ca++ and Mg++ ions. The ACP is antibody independent, requiring Mg++ ions and a heat-labile 90 kDa factor B-like protein for activity. Proteins considered homologues of C1q, C3 and C4 (C2n) of the mammalian complement system have been isolated from nurse shark serum. Shark C1q is composed of at least two chain types each showing 50% identity to human C1q chains A and B. Partial sequence of the globular domain of one of the chains shows it to be C1q-like rather than like mannan-binding protein. N-terminal amino acid sequences of the alpha and beta chain of shark C3 and C4 molecules show significant identity with corresponding human C3 and C4 chains. A sequence representing shark C4 gamma chain, shows little similarity to human C4 gamma chain. The terminal shark components C8n and C9n are functional analogues of mammalian C8 and C9. Anaphylatoxin activity has been demonstrated in activated shark serum, and porcine C5a desArg induces shark leucocyte chemotaxis. The deduced amino acid sequence of a partial C3 cDNA clone from the nurse shark shows 50%, 30% and 24% homology with the corresponding region of mammalian C3, C4 and alpha 2-macroglobulin. Deduced amino acid sequence data from partial Bf/C2 cDNA clones, two from the nurse shark and one from the Japanese dogfish, suggest that at least one species of elasmobranch has two distinct Bf/C2 genes.

  6. Detecting thermal phase transitions in corneal stroma by fluorescence micro-imaging analysis

    Matteini, P.; Rossi, F.; Ratto, F.; Bruno, I.; Nesi, P.; Pini, R.

    2008-02-01

    Thermal modifications induced in corneal stroma were investigated by the use of fluorescence microscopy. Freshly extracted porcine corneas were immersed for 5 minutes in a water bath at temperatures in the 35-90°C range and stored in formalin. The samples were then sliced in 200-μm-thick transversal sections and analyzed under a stereomicroscope to assess corneal shrinkage. Fluorescence images of the thermally treated corneal samples were acquired using a slow-scan cooled CCD camera, after staining the slices with Indocyanine Green (ICG) fluorescent dye which allowed to detect fluorescence signal from the whole tissue. All measurements were performed using an inverted epifluorescence microscope equipped with a mercury lamp. The thermally-induced modifications to the corneal specimens were evaluated by studying the grey level distribution in the fluorescence images. For each acquired image, Discrete Fourier Transform (DFT) and entropy analyses were performed. The spatial distribution of DFT absolute value indicated the spatial orientation of the lamellar planes, while entropy was used to study the image texture, correlated to the stromal structural transitions. As a result, it was possible to indicate a temperature threshold value (62°C) for high thermal damage, resulting in a disorganization of the lamellar planes and in full agreement with the measured temperature for corneal shrinkage onset. Analysis of the image entropy evidenced five strong modifications in stromal architecture at temperatures of ~45°C, 53°C, 57°C, 66°C, 75°C. The proposed procedure proved to be an effective micro-imaging method capable of detecting subtle changes in corneal tissue subjected to thermal treatment.

  7. A new methodology for fluorescence analysis of composite resins used in anterior direct restorations.

    de Lima, Liliane Motta; Abreu, Jessica Dantas; Cohen-Carneiro, Flavia; Regalado, Diego Ferreira; Pontes, Danielson Guedes

    2015-01-01

    The aim of this study was to use a new methodology to evaluate the fluorescence of composite resins for direct restorations. Microhybrid (group 1, Amelogen; group 2, Opallis; group 3, Filtek Z250) and nanohybrid (group 4, Filtek Z350 XT; group 5, Brilliant NG; group 6, Evolu-X) composite resins were analyzed in this study. A prefabricated matrix was used to prepare 60 specimens of 7.0 × 3.0 mm (n = 10 per group); the composite resin discs were prepared in 2 increments (1.5 mm each) and photocured for 20 seconds. To establish a control group of natural teeth, 10 maxillary central incisor crowns were horizontally sectioned to create 10 discs of dentin and enamel tissues with the same dimensions as the composite resin specimens. The specimens were placed in a box with ultraviolet light, and photographs were taken. Aperture 3.0 software was used to quantify the central portion of the image of each specimen in shades of red (R), green (G), and blue (B) of the RGB color space. The brighter the B shade in the evaluated area of the image, the greater the fluorescence shown by the specimen. One-way analysis of variance revealed significant differences between the groups. The fluorescence achieved in group 1 was statistically similar to that of the control group and significantly different from those of the other groups (Bonferroni test). Groups 3 and 4 had the lowest fluorescence values, which were significantly different from those of the other groups. According to the results of this study, neither the size nor the amount of inorganic particles in the evaluated composite resin materials predicts if the material will exhibit good fluorescence.

  8. Direct analysis of biological samples by total reflection X-ray fluorescence

    Lue M, Marco P.; Hernandez-Caraballo, Edwin A.

    2004-01-01

    The technique of total reflection X-ray fluorescence (TXRF) is well suited for the direct analysis of biological samples due to the low matrix interferences and simultaneous multi-element nature. Nevertheless, biological organic samples are frequently analysed after digestion procedures. The direct determination of analytes requires shorter analysis time, low reactive consumption and simplifies the whole analysis process. On the other hand, the biological/clinical samples are often available in minimal amounts and routine studies require the analysis of large number of samples. To overcome the difficulties associated with the analysis of organic samples, particularly of solid ones, different procedures of sample preparation and calibration to approach the direct analysis have been evaluated: (1) slurry sampling, (2) Compton peak standardization, (3) in situ microwave digestion, (4) in situ chemical modification and (5) direct analysis with internal standardization. Examples of analytical methods developed by our research group are discussed. Some of them have not been previously published, illustrating alternative strategies for coping with various problems that may be encountered in the direct analysis by total reflection X-ray fluorescence spectrometry

  9. Nanomedicine and the complement paradigm.

    Moghimi, S Moein; Farhangrazi, Z Shadi

    2013-05-01

    The role of complement in idiosyncratic reactions to nanopharmaceutical infusion is receiving increasing attention. We discuss this in relation to nanopharmaceutical development and the possible use of complement inhibitors to prevent related adverse reactions. We further call on initiation of genetic association studies to unravel the genetic basis of nanomedicine infusion-related adverse responses, since most of the polymorphic genes in the genome belong to the immune system. In this paper, idiosyncratic reactions based on complement activation are discussed in the context of newly available complement inhibitors. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. X-ray fluorescence analysis of ancient and medieval brass artifacts from south Moravia

    Hložek, M.; Komoróczy, B.; Trojek, T.

    2012-01-01

    This paper deals with an investigation of archeological finds using X-ray fluorescence analysis and microanalysis. The main aim of the investigation was to prove the production of brass in the South Moravian Region (part of the Czech Republic) in former times. The probable brass production technology is described. Various objects dating back to Antiquity and to the Middle Ages were investigated using two X-ray fluorescence systems, and the results of the analyses are discussed. The measurements showed, e.g., that fragments of Roman scale armor and a belt fitting dating back to Antiquity were made of brass. Brass was also identified on the surfaces of various ancient and medieval molds and melting pots. - Highlights: ► Semiquantitative X-ray fluorescence analysis of archeological finds. ► Two different gilding techniques of a brass belt terminal found in Brno. ► Use of brass before the Great Moravian period. ► Evidence of brass casting in the 12th century in Brno.

  11. X-ray fluorescence analysis of ancient and medieval brass artifacts from south Moravia

    Hlozek, M. [Methodical Centre of Conservation-Technical Museum in Brno, Purkynova 105, 612 00 Brno (Czech Republic); Komoroczy, B. [Institute of Archeology of the Academy of Science of the Czech Republic, Kralovopolska 147, 612 00 Brno (Czech Republic); Trojek, T., E-mail: tomas.trojek@fjfi.cvut.cz [Department of Dosimetry and Application of Ionizing Radiation, Czech Technical University in Prague, Brehova 7, 115 19 Praha 1 (Czech Republic)

    2012-07-15

    This paper deals with an investigation of archeological finds using X-ray fluorescence analysis and microanalysis. The main aim of the investigation was to prove the production of brass in the South Moravian Region (part of the Czech Republic) in former times. The probable brass production technology is described. Various objects dating back to Antiquity and to the Middle Ages were investigated using two X-ray fluorescence systems, and the results of the analyses are discussed. The measurements showed, e.g., that fragments of Roman scale armor and a belt fitting dating back to Antiquity were made of brass. Brass was also identified on the surfaces of various ancient and medieval molds and melting pots. - Highlights: Black-Right-Pointing-Pointer Semiquantitative X-ray fluorescence analysis of archeological finds. Black-Right-Pointing-Pointer Two different gilding techniques of a brass belt terminal found in Brno. Black-Right-Pointing-Pointer Use of brass before the Great Moravian period. Black-Right-Pointing-Pointer Evidence of brass casting in the 12th century in Brno.

  12. X-ray fluorescence analysis of neodymium oxide/oxalate for rare earth impurities

    Chandola, L.C.; Mohile, A.N.

    1977-01-01

    An X-ray fluorescence method for the determination of cesium, praseodymium, samarium, europium and gadolinium in pure neodymium oxide and oxalate is described. The oxide sample is converted to oxalate and mixed with a binder (boric acid) to obtain a pressed circular pellet. The amount of sample needed for analysis is reduced by making use of the double layer pellet technique. A tungsten target X-ray tube is employed to irradiate the sample and a Philips PW 1220 semiautomatic X-ray spectrometer with a LiF (200) crystal is used to analyse the fluorescent X-rays. The minimum determination limit is 0.01 percent for all rare earths determined except for europium for which the limit is 0.005 percent. Three sigma detection limits have been calculated. (author)

  13. Fundamental parameters method for quantitative energy dispersive x-ray fluorescence analysis

    Demirel, H.; Zararsiz, A.

    1986-01-01

    In this study, the requirement of the standart material in photon excited energy distributed X-ray fluorescence analysis has been removed. The interaction of X-rays with matter has been taken into account. A computer program has been developed by using the fundamental parameters of X-ray fluorescence technique and the spectral intensity 'K' of pure elements at saturation thickness has been obtained. For experimental purpose a convenient source-target-detector geometry has been designed. In order to excite the samples,Cd-109 radioisotope source has been used. The peak intensities has been obtained in a vacum chamber by counting the emitted X-rays. The calculation of concentration has been performed for double mixed samples correcting the effects of absorption and enchancement factors. The results were in conformity with their certificate values. (author)

  14. Analysis of cell-tissue grafts under weightless conditions using confocal fluorescence microscopy

    Volova, L. T.; Milyakova, M. N.; Rossinskaya, V. V.; Boltovskaya, V. V.; Kulagina, L. N.; Kurganskaya, L. V.; Timchenko, P. E.; Timchenko, E. V.; Zherdeva Taskina, Larisa A.

    2015-03-01

    The research results of monitoring of viable cells in a cellular-tissue graft using confocal laser fluorescence microscopy at 488 nm and 561 nm with the use of fluorophore propidium iodide (propidium iodide, PI Sigma Aldrich USA) are presented. The processing of the received images was carried out using the software ANDOR. It is experimentally shown that the method of confocal fluorescence microscopy is one of the informational methods for detecting cells populated in a 3-D bio-carrier with a resolution of at least 400 nm. Analysis of the received micrographs suggests that the cells that were in a bio-carrier for 30 days in a synchronous ground-based experiment retained their viability compared to a similar space-based experiment in which the cells were hardly detected in a bio-carrier.

  15. Multielemental analysis in Brazilian cigarettes using total reflection X-ray fluorescence with synchrotron radiation

    Serpa, Renata F.B.; Jesus, Edgar F.O. de; Lopes, Ricardo T.; Moreira, Silvana

    2005-01-01

    In order to identify major and trace elements in conventional and light Brazilian cigarettes, Total Reflection X-Ray Fluorescence with Synchrotron Radiation (SR-TXRF) was used. The fluorescence measurements were carried out at Brazilian Synchrotron Light Laboratory, Campinas - Sao Paulo. This technique enables detection limit is in the ngg -1 range, which is very useful in elemental tobacco smoke analysis, since it presents most of its elements at a trace level. The major elements identified in tobacco samples were: S, Cl, K, Ca, Mn, Fe and Cd, and the trace elements were: Ti, Cr, Ni, Cu, Zn, Br, Rb, Sr and Ba. However in tobacco smoke samples, there were only two major elements: K and Ca, the others were present a trace level. The rate transfer of tobacco to tobacco smoke was about 2.5 % for all elements studied. (author)

  16. Nondestructive analysis of silver in gold foil using synchrotron radiation X-ray fluorescence spectrometry

    Kasamatsu, Masaaki; Suzuki, Yasuhiro; Suzuki, Shinichi; Nakanishi, Toshio; Shimoda, Osamu; Nishiwaki, Yoshinori; Miyamoto, Naoki

    2005-01-01

    Small particles of gold foil detached from an indoor decoration might be important evidence to associate a suspect with a crime scene. We have investigated the application of elemental analysis using synchrotron radiation X-ray fluorescence spectrometry to discriminate small particles of gold foil. Eight kinds of gold foil samples collected in Japan were used in the experiments. As a result of synchrotron radiation X-ray fluorescence spectrometry, only two elements, gold and silver, were detected from all gold foil samples. The intensity ratios of AgK α /AuL α showed good correlation with the content ratios of Ag/Au. The variation of intensity ratio within a same sample was sufficiently small compared with those of different samples. Therefore the comparison of this intensity ratio can be an effective method to discriminate small particles originating from different types of gold foil. (author)

  17. Role of importance of X-ray fluorescence analysis of forensic samples

    Jha, Shailendra; Sharma, M.

    2009-01-01

    Full text: In the field of forensic science, it is very important to investigate the evidential samples obtained at various crime scenes. X-ray fluorescence (XRF) is used widely in forensic science [1]. Its main strength is its non-destructive nature, thus preserving evidence [2, 3]. In this paper, we report the application of XRF to examine the evidences like purity gold and silver jewelry (Indian Ornaments), remnants of glass pieces and paint chips recovered from crime scenes. The experimental measurements on these samples have been made using X-ray fluorescence spectrometer (LAB Center XRF-1800) procured from Shimazdu Scientific Inst., USA. The results are explained in terms of quantitative/ qualitative analysis of trace elements. (author)

  18. Beer analysis by synchrotron radiation total reflection X-ray fluorescence (SR-TXRF)

    Moreira, Silvana; Vives, Ana Elisa S. de; Nascimento Filho, Virgilio F.; Zucchi, Orgheda L.D.A.

    2005-01-01

    In this work the concentrations of P, S, Cl, K, Ca, Mn, Fe, Zn and Br in twenty-nine brands of national and international beers were determined by Synchrotron Radiation Total Reflection X-Ray Fluorescence analysis (SR-TXRF). The results were compared with the limits established by the Brazilian Legislation and the nutritive values established by National Agricultural Library (NAL). The measurements were performed at the X-ray Fluorescence Beamline at Synchrotron Light Source Laboratory, in Campinas, Sao Paulo, Brazil, using a polychromatic beam for excitation. A small volume of 5 μL of sample beers containing just an internal standard, used to correct geometry effects, were analyzed without any pre-treatment. The measuring time was 100 s and the detection limits obtained varied from 1μg.L -1 for Mn and Fe to 15μg.L -1 for P. (author)

  19. Computer-assisted sperm morphometry fluorescence-based analysis has potential to determine progeny sex.

    Santolaria, Pilar; Pauciullo, Alfredo; Silvestre, Miguel A; Vicente-Fiel, Sandra; Villanova, Leyre; Pinton, Alain; Viruel, Juan; Sales, Ester; Yániz, Jesús L

    2016-01-01

    This study was designed to determine the ability of computer-assisted sperm morphometry analysis (CASA-Morph) with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa (SX and SY, respectively). Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average (P potential to find differences between X- and Y-chromosome-bearing spermatozoa in bovine species although more studies are needed to increase the precision of sex determination by this technique.

  20. Quantitative analysis and metallic coating thickness measurements by X-ray fluorescence

    Negrea, Denis; Ducu, Catalin; Malinovschi, Viorel; Moga, Sorin; Boicea, Niculae

    2009-01-01

    Full text: This paperwork covers the use of X-ray fluorescence (XRF) for determining the concentration and the coating thickness on metallic samples. The analysis method presented here may also be applicable to other coatings, providing that the elemental nature of the coating and substrate are compatible with the technical aspects of XRF, such as the absorption coefficient of the system, primary radiation, fluorescent radiation and type of detection. For the coating thickness measurement it was used the substrate-line attenuation method and a computing algorithm was developed. Its advantage relies in the fact that no special calibration with standard samples having different layer thickness is needed. The samples used for evaluation were metallic pieces of iron with zinc-nickel coatings of different thickness obtained by electrochemical deposition. (authors)

  1. Quantitative analysis and metallic coating thickness measurements by X-ray fluorescence

    Negrea, Denis; Ducu, Catalin; Malinovschi, Viorel; Moga, Sorin; Boicea, Niculae

    2009-01-01

    This work deals with the use of X-ray fluorescence (XRF) for determining the concentration and the coating thickness on metallic samples. The analysis method presented here may also be applicable to other coatings, providing that the elemental nature of the coating and substrate are compatible with the technical aspects of XRF, such as the absorption coefficient of the system, primary radiation, fluorescent radiation and type of detection. For the coating thickness measurement it was used the substrate-line attenuation method and an algorithm was developed. Its advantage relies in the fact that no special calibration with standard samples having different layer thickness is needed. The samples used for evaluation were metallic pieces of iron with zinc-nickel coatings of different thickness obtained by electrochemical deposition. (authors)

  2. Data analysis of x-ray fluorescence holography by subtracting normal component from inverse hologram

    Happo, Naohisa; Hayashi, Kouichi; Hosokawa, Shinya

    2010-01-01

    X-ray fluorescence holography (XFH) is a powerful technique for determining three-dimensional local atomic arrangements around a specific fluorescing element. However, the raw experimental hologram is predominantly a mixed hologram, i.e., a mixture of hologram generated in both normal and inverse modes, which produces unreliable atomic images. In this paper, we propose a practical subtraction method of the normal component from the inverse XFH data by a Fourier transform for the calculated hologram of a model ZnTe cluster. Many spots originating from the normal components could be properly removed using a mask function, and clear atomic images were reconstructed at adequate positions of the model cluster. This method was successfully applied to the analysis of experimental ZnTe single crystal XFH data. (author)

  3. Hyperspectral fluorescence imaging coupled with multivariate image analysis techniques for contaminant screening of leafy greens

    Everard, Colm D.; Kim, Moon S.; Lee, Hoyoung

    2014-05-01

    The production of contaminant free fresh fruit and vegetables is needed to reduce foodborne illnesses and related costs. Leafy greens grown in the field can be susceptible to fecal matter contamination from uncontrolled livestock and wild animals entering the field. Pathogenic bacteria can be transferred via fecal matter and several outbreaks of E.coli O157:H7 have been associated with the consumption of leafy greens. This study examines the use of hyperspectral fluorescence imaging coupled with multivariate image analysis to detect fecal contamination on Spinach leaves (Spinacia oleracea). Hyperspectral fluorescence images from 464 to 800 nm were captured; ultraviolet excitation was supplied by two LED-based line light sources at 370 nm. Key wavelengths and algorithms useful for a contaminant screening optical imaging device were identified and developed, respectively. A non-invasive screening device has the potential to reduce the harmful consequences of foodborne illnesses.

  4. Beer analysis by synchrotron radiation total reflection X-ray fluorescence (SR-TXRF)

    Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo. Dept. de Recursos Hidricos]. E-mail: silvana@fec.unicamp.br; Vives, Ana Elisa S. de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Nascimento Filho, Virgilio F. [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Instrumentacao Nuclear]. E-mail: virgilio@cena.usp.br; Zucchi, Orgheda L.D.A. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas de Ribeirao Preto]. E-mail: olzucchi@fcfrp.usp.br

    2005-07-01

    In this work the concentrations of P, S, Cl, K, Ca, Mn, Fe, Zn and Br in twenty-nine brands of national and international beers were determined by Synchrotron Radiation Total Reflection X-Ray Fluorescence analysis (SR-TXRF). The results were compared with the limits established by the Brazilian Legislation and the nutritive values established by National Agricultural Library (NAL). The measurements were performed at the X-ray Fluorescence Beamline at Synchrotron Light Source Laboratory, in Campinas, Sao Paulo, Brazil, using a polychromatic beam for excitation. A small volume of 5 {mu}L of sample beers containing just an internal standard, used to correct geometry effects, were analyzed without any pre-treatment. The measuring time was 100 s and the detection limits obtained varied from 1{mu}g.L{sup -1} for Mn and Fe to 15{mu}g.L{sup -1} for P. (author)

  5. The isotope X-ray fluorescence analysis and its application in geochemical investigations in Greenland

    Kunzendorf, H.

    1973-01-01

    The applicability of the isotope X-ray fluorescence analysis (IRFA) in the geochemical exploration was investigated. Detection limits of about 0.1% for the elements Ti, Zr, Nb, Mo and La+Ce were achieved in terrain measurements. Detection limits of 0.05% were found in the analysis of Cr, Ni, Cu, Zn, Zr, Nb, Mo, La+Ce and Pb in finely grinded rock samples. Geochemical investigations were carried out in the Ilimaussag-Intrusion in south Greenland as well as on the Mo deposits Malmbjerg and the heavy mineral occurence 'kote 800' in East Greenland. The use of portable IRFA equipment proved to be particularly suitable in the analysis of bed rocks, loose rock samples such as moraine material, in the semi-quantitative analysis of heavy mineral concentrates, the analysis of bored cores during the boring programme, as well as the analysis of finely grinded rock samples. (ORU) [de

  6. 3D Synchrotron μ-x-ray fluorescence analysis on human bones

    Zoeger, N.; Wobrauschek, P.; Streli, C.; Chinea-Cano, E.; Wegrzynek, D.; Roschger, P.; Simon, R.; Staub, S.; Falkenberg, G.

    2004-01-01

    A comparison between μ-x-ray fluorescence tomography and confocal μ-x-ray fluorescence analysis (μ-XRF) will be presented. These techniques were used to study the three dimensional (3D) elemental distribution in human bone. Since bone shows very strong inhomogeneities in structure as well as in distribution of the chemical elements, two dimensional (2D) analysis (element mapping) of the samples always led to difficulties in interpreting the results and assigning elemental distributions to microscopic structures. Tomography scans in fluorescence and absorption mode have been carried out simultaneously at the fluo-topo beamline at ANKA, Karlsruhe, to determine the distribution of the elements over the depth of the previously prepared sample from human patella. A monochromatized x-ray beam (17 keV) from a bending magnet station focused by a compound refractive lens to a beamsize of 10 x 5 μm was used to perform the measurements. The transmitted beam signal measured with the SD detector was utilized to apply a simplified absorption correction to XRF tomographic images. Based on the XRF sinograms the elemental distribution within the object cross-section was reconstructed by means of filtered backprojection. The same section of human bone has been analyzed by confocal μ-XRF at HASYLAB, Hamburg, Germany beamline L. With this experiment two polycapillary half lenses were used; one for focusing the previously monochromatized primary x-ray beam onto the sample and the second half lens in front of a Si(Li) detector to get a small inspected area. By overlapping the two foci of the lenses a very well defined volume of investigation could be defined. Scanning the sample up- and downstream it was possible to determine the elemental distribution in depth of the sample. An absorption correction has been applied to get a corrected fluorescence image of the sample. Both methods showed consistent results and allowed a precise localization of the elements of interest. (author)

  7. Fast neutron activation analysis and radioisotope X-ray fluorescence study on KALEWA and NAMMA coal

    Naing-Win

    1981-07-01

    Kalewa coal was studied with Fast Neutron Activation Analysis (FNAA) technique, employing KAMAN A-710 neutron generator and HP(Ge) detector coupled to ''Canberra'' series 30 MCA. Sequential irradiation and dual aluminium foil monitoring method was employed. Simultaneous multielement analysis was carried out. Namma Coal was studied with radioisotope X-ray Fluorescence (XRF) technique, employing Co-57 exciter source and HP(Ge) detector coupled to ''Canberra'' series 40 MCA. In both FNAA and XRF study, the results obtained were compared to that obtained with Atomic Absorption Spectrophotometry (AAS) technique. Finally, the results were reviewed together with those obtained from similar work on coal with FNAA and XRF techniques. (author)

  8. Data processing of X-ray fluorescence analysis using an electronic computer

    Yakubovich, A.L.; Przhiyalovskij, S.M.; Tsameryan, G.N.; Golubnichij, G.V.; Nikitin, S.A.

    1979-01-01

    Considered are problems of data processing of multi-element (for 17 elements) X-ray fluorescence analysis of tungsten and molybdenum ores. The analysis was carried out using silicon-lithium spectrometer with the energy resolution of about 300 eV and a 1024-channel analyzer. A characteristic radiation of elements was excited with two 109 Cd radioisotope sources, their general activity being 10 mCi. The period of measurements was 400 s. The data obtained were processed with a computer using the ''Proba-1'' and ''Proba-2'' programs. Data processing algorithms and computer calculation results are presented

  9. Fast neutron activation analysis and radioisotope X-ray fluorescence study on KALEWA and NAMMA coal

    Naing-Win, [Arts and Science University, Yangon (Myanmar)

    1981-07-01

    Kalewa coal was studied with Fast Neutron Activation Analysis (FNAA) technique, employing KAMAN A-710 neutron generator and HP(Ge) detector coupled to ``Canberra`` series 30 MCA. Sequential irradiation and dual aluminium foil monitoring method was employed. Simultaneous multielement analysis was carried out. Namma Coal was studied with radioisotope X-ray Fluorescence (XRF) technique, employing Co-57 exciter source and HP(Ge) detector coupled to ``Canberra`` series 40 MCA. In both FNAA and XRF study, the results obtained were compared to that obtained with Atomic Absorption Spectrophotometry (AAS) technique. Finally, the results were reviewed together with those obtained from similar work on coal with FNAA and XRF techniques. (author).

  10. Application of direct peak analysis to energy dispersive x-ray fluorescence spectra

    Nielson, K.K.

    1977-07-01

    A modified Covell method for direct peak analysis has been applied to energy dispersive x-ray fluorescence spectra. The method is background independent and is well-suited to computerized data reduction. It provides acceptable precision, minimizes errors from instrumental gain shift, and permits peak overlap correction. Peak overlap errors exhibit both positive and negative nodes as a function of peak separation distance, and are corrected using concentration ratios determined from thin, single-element standards. Peak precisions and overlaps are evaluated as a function of window width to aid in width selection. Least-square polynomial smoothing prior to peak analysis significantly improves peak area precisions without significantly affecting their accuracies

  11. Exploratory analysis for the identification of false banknotes using portable X-ray Fluorescence spectrometer.

    Zamalloa Jara, M A; Luízar Obregón, C; Araujo Del Castillo, C

    2018-05-01

    The aim of this study was to verify if a portable X-ray fluorescence (pXRF) spectrometer can recognize the security features in banknotes that are reproducible by counterfeiters. Peruvian Nuevo Sol banknotes were studied: 4 genuine and 3 fake ones, in 11 points of analysis for each one, at all 77 data set. The correlation analysis of spectra among original notes was 1.0, and there was no correlation with fake banknotes. pXRF prove that two security features were reproducible for counterfeiters. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. The x-rays fluorescence applied to the analysis of alloys

    Gutierrez, D.A.

    1997-01-01

    This work is based on the utilization of the Fluorescence of X Rays. This technique of non destructive trial, has the purpose to establish a routine method, for the control of the conformation of industrial samples used. It makes an analysis with a combination of the algorithms of Rasberry-Heinrich and Claisse-Thinh. Besides, the numerical implementation of non usual techniques in this type of analysis. Such as the Linear Programming applied to the solution of super determined systems, of equations and the utilization of methods of relaxation to facilitate the convergence to the solutions. (author) [es

  13. Analysis of kiwi fruit (Accented deliciosa) by energy dispersive X-ray fluorescence spectra

    Oliveira, Ana Claudia S.; Oliveira, Marcia L. de; Silva, Lucia C.A.S.; Arthur, Valter; Almeida, Eduardo

    2011-01-01

    The search for a healthy life has led consumers to eat fruits and vegetables in place of manufactured products, however, the demand for minimally processed products has evolved rapidly. The kiwi has at least eight nutrients beneficial to health: calcium, magnesium, manganese, phosphorus, iron, potassium, sodium and has also high vitamin C, which has wide acceptance in consumer markets. Energy dispersive spectroscopy X-ray (EDX) is the analytical technique used for elemental analysis or chemical characterization of a sample. It is a variant of fluorescence spectroscopy X-ray based on the sample through an investigation of interactions between electromagnetic radiation and matter, analyzing X-rays emitted by matter in response to being struck by charged particles. The aim of this study were to determine potassium, calcium, iron and bromine (K, Ca, Fe and Br, respectively) present in kiwifruit using the technique of fluorescence X-ray energy dispersive (EDXRF). Kiwifruit were peeled, washed and cut into slices and freeze-dried. After drying the sample was held digestion and subsequent reading of the same equipment in the X-ray fluorescence energy dispersive (EDXRF). The results indicated that the contents of potassium, calcium, iron and bromine are present in kiwifruit as expected when compared to Brazilian Table of Food Composition. (author)

  14. Light emitting diode, photodiode-based fluorescence detection system for DNA analysis with microchip electrophoresis.

    Hall, Gordon H; Glerum, D Moira; Backhouse, Christopher J

    2016-02-01

    Electrophoretic separation of fluorescently end-labeled DNA after a PCR serves as a gold standard in genetic diagnostics. Because of their size and cost, instruments for this type of analysis have had limited market uptake, particularly for point-of-care applications. This might be changed through a higher level of system integration and lower instrument costs that can be realized through the use of LEDs for excitation and photodiodes for detection--if they provide sufficient sensitivity. Here, we demonstrate an optimized microchip electrophoresis instrument using polymeric fluidic chips with fluorescence detection of end-labeled DNA with a LOD of 0.15 nM of Alexa Fluor 532. This represents orders of magnitude improvement over previously reported instruments of this type. We demonstrate the system with an electrophoretic separation of two PCR products and their respective primers. We believe that this is the first LED-induced fluorescence microchip electrophoresis system with photodiode-based detection that could be used for standard applications of PCR and electrophoresis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Fluorescence spectroscopy for the detection of potentially malignant disorders of the oral cavity: analysis of 30 cases

    Francisco, A L N; Correr, W R; Kurachi, C; Azevedo, L H; Galletta, V K; Pinto, C A L; Kowalski, L P

    2014-01-01

    Oral cancer is a major health problem worldwide and although early diagnosis of potentially malignant and malignant diseases is associated with better treatment results, a large number of cancers are initially misdiagnosed, with unfortunate consequences for long-term survival. Fluorescence spectroscopy is a noninvasive modality of diagnostic approach using induced fluorescence emission in tumors that can improve diagnostic accuracy. The objective of this study was to determine the ability to discriminate between normal oral mucosa and potentially malignant disorders by fluorescence spectroscopy. Fluorescence investigation under 408 and 532 nm excitation wavelengths was performed on 60 subjects, 30 with potentially malignant disorders and 30 volunteers with normal mucosa. Data was analyzed to correlate fluorescence patterns with clinical and histopathological diagnostics. Fluorescence spectroscopy used as a point measurement technique resulted in a great variety of spectral information. In a qualitative analysis of the fluorescence spectral characteristics of each type of injury evaluated, it was possible to discriminate between normal and abnormal oral mucosa. The results show the potential use of fluorescence spectroscopy for an improved discrimination of oral disorders. (paper)

  16. Chemical analysis of copper and gold ores from Papua New Guinea (PNG) by means of X-ray fluorescence analysis

    Sugiyama, Kazumasa; Waseda, Yoshio; Pangum, L.S.; Witney, J.Y.

    1995-01-01

    X-ray fluorescence analysis (XRF) has been made for determining the contents of copper and gold in ores from PNG mines. An internal standard method of Cu Kα/Er Lβ 1 was used for the analysis of the common copper porphyry samples. The results clearly indicate that this technique is quite effective for analyzing any copper ores with complicated matrix elements. On the other hand, an addition method of the diluted Au solution was applied to gold ores. The results of the present XRF analysis were found to reasonably agree with those obtained by the inductively coupled plasma (ICP) technique. (author)

  17. Advances in low atomic number element analysis by wavelength dispersive x-ray fluorescence spectrometry

    Vrebos, B.

    1996-01-01

    Traditionally, the analysis of low atomic number has been a chal1enging task for wavelength dispersive x-ray fluorescence spectrometry. Among the most important factors influencing analysis of the low atomic number elements (from Z=11 downwards) are the fluorescence yield, absorption and the dispersion. The effect of each of these factors on the overall performance will be illustrated. The long wavelengths involved (longer than I nm) used to pose severe problems concerning the monochromator used. Early instruments relied on lead stearate or Blodgett Langmuir soap films for the diffraction of the characteristic radiation. Nowadays, synthetic multilayers are commonly used. The performance of these multilayers is determined by the reflectivity, the resolution and the absorption of the characteristic radiation to be diffracted. These parameters can be optimised by adequately selecting the composition of the materials involved. The sensitivity of the modem instruments is sufficient to allow quantitative analysis. However, this aspect of WDS XRF is still met with considerable scepticism. Examples of quantitative analysis will be given to illustrate the current capability

  18. Proton induced X-Ray fluorescence study as a tool trace element analysis

    El-Kady, Ahmed A.

    1978-01-01

    Usefulness and limitations of trace elemental analysis by high energy charged particles and photon induced X-ray have been discussed. Comparison with the well established neutron activation analysis technique is also given. Back-ground radiation due to bremsstrahlung from secondary electrons and due to charged particle bremsstrahlung have been reviewed for different projectiles. The sensitivity of elemental analysis by proton induced X-ray fluorescence have been examined by measuring the characteristic X-ray emission cross section for K and L transitions of many elements and for different proton energies and compared with theroretical values. The discussion given in this report show that with suitable proton generator and a high resolution X-ray detector, proton X-ray fluorescence technique is capable of analyzing many elements simultaneously at the part per million level and offers a rapid and reliable method for trace element analysis. Data on water, blood and tissue samples given in this report are few examples of many possible applications

  19. The studies of post-medieval glass by multivariate and X-ray fluorescence analysis

    Kierzek, J.; Kunicki-Goldfinger, J.

    2002-01-01

    Multivariate statistical analysis of the results obtained by energy dispersive X-ray fluorescence analysis has been used in the study of baroque vessel glasses originated from central Europe. X-ray spectrometry can be applied as a completely non-destructive, non-sampling and multi-element method. It is very useful in the studies of valuable historical artefacts. For the last years, multivariate statistical analysis has been developed as an important tool for the archaeometric purposes. Cluster, principal component and discriminant analysis were applied for the classification of the examined objects. The obtained results show that these statistical tools are very useful and complementary in the studies of historical objects. (author)

  20. An image analysis system for near-infrared (NIR) fluorescence lymph imaging

    Zhang, Jingdan; Zhou, Shaohua Kevin; Xiang, Xiaoyan; Rasmussen, John C.; Sevick-Muraca, Eva M.

    2011-03-01

    Quantitative analysis of lymphatic function is crucial for understanding the lymphatic system and diagnosing the associated diseases. Recently, a near-infrared (NIR) fluorescence imaging system is developed for real-time imaging lymphatic propulsion by intradermal injection of microdose of a NIR fluorophore distal to the lymphatics of interest. However, the previous analysis software3, 4 is underdeveloped, requiring extensive time and effort to analyze a NIR image sequence. In this paper, we develop a number of image processing techniques to automate the data analysis workflow, including an object tracking algorithm to stabilize the subject and remove the motion artifacts, an image representation named flow map to characterize lymphatic flow more reliably, and an automatic algorithm to compute lymph velocity and frequency of propulsion. By integrating all these techniques to a system, the analysis workflow significantly reduces the amount of required user interaction and improves the reliability of the measurement.

  1. Instrumental aspects of tube-excited energy-dispersive X-ray fluorescence analysis

    Adams, F.; Nullens, H.; Espen, P. van

    1983-01-01

    Energy-dispersive X-ray fluorescence spectrometry is an attractive and widely used method for sensitive multi-element analysis. The method suffers from the extreme density of spectral components in a rather limited energy range which implies the need for computer based spectrum analysis. The method of iterative least squares analysis is the most powerful tool for this. It requires a systematic and accurate description of the spectral features. Other important necessities for accurate analysis are the calibration of the spectrometer and the correction for matrix absorption effects in the sample; they can be calculated from available physical constants. Ours and similar procedures prove that semi-automatic analyses are possible with an accuracy of the order of 5%. (author)

  2. X-ray fluorescence analysis of archaeological finds and art objects: Recognizing gold and gilding

    Trojek, Tomáš; Hložek, Martin

    2012-01-01

    Many cultural heritage objects were gilded in the past, and nowadays they can be found in archeological excavations or in historical buildings dating back to the Middle Ages, or from the modern period. Old gilded artifacts have been studied using X-ray fluorescence analysis and 2D microanalysis. Several techniques that enable the user to distinguish gold and gilded objects are described and then applied to investigate artifacts. These techniques differ in instrumentation, data analysis and numbers of measurements. The application of Monte Carlo calculation to a quantitative analysis of gilded objects is also introduced. - Highlights: ► Three techniques of gilding identification with XRF analysis are proposed. ► These techniques are applied to gold and gilded art and archeological objects. ► Composition of a substrate material is determined by a Monte Carlo simulation.

  3. Quantitative X ray analysis system. User's manual and guide to X ray fluorescence technique

    2009-01-01

    This guide covers trimmed and re-arranged version 3.6 of the Quantitative X ray Analysis System (QXAS) software package that includes the most frequently used methods of quantitative analysis. QXAS is a comprehensive quantitative analysis package that has been developed by the IAEA through research and technical contracts. Additional development has also been carried out in the IAEA Laboratories in Seibersdorf where QXAS was extensively tested. New in this version of the manual are the descriptions of the Voigt-profile peak fitting, the backscatter fundamental parameters' and emission-transmission methods of chemical composition analysis, an expanded chapter on the X ray fluorescence physics, and completely revised and increased number of practical examples of utilization of the QXAS software package. The analytical data accompanying this manual were collected in the IAEA Seibersdorf Laboratories in the years 2006/2007

  4. Fluorescence Analysis on the Roots of Rauvolfia Serpentina (L.) Benth. Ex Kurz Under UV Radiation

    Selvam, A.B.D; Bandyopadhyay, S.

    2005-01-01

    The present study deals with an analysis of the roots of Rauvolfia serpentine (L) Benth. Ex Kurz under ultraviolet radiation and also under daylight. The coarsely powdered roots were treated with various chemical reagents and the characteristic fluorescence patterns emitted were recorded and are reported in this paper. This study was undertaken as a pharmacognostic standardization to ascertain the authenticity of the roots of this plant in its crude form and also to check any adulteration that may be used in trade. PMID:22557172

  5. Analysis of signal to background ratio in synchrotron radiation X-ray fluorescence

    Sakurai, Kenji; Gohshi, Yohichi; Iida, Atsuo.

    1988-01-01

    The signal to background (S/B) ratio in energy dispersive X-ray fluorescence using synchrotron radiation (SR) was quantitatively analyzed. The S/B ratio, which has been significantly improved by taking advantage of the polarized nature of SR, was found to be strongly dependent on geometrical factors of the measurement system. From the analysis on the origin of the scattered background, the dependence of the S/B ratio on the geometry was quantitatively explained, mainly by the polarization properties of SR. Experimental conditions could be optimized by adjusting the degree of polarization of the incident beam and the detector solid angle. (author)

  6. Pattern recognition on X-ray fluorescence records from Copenhagen lake sediments using principal component analysis

    Schreiber, Norman; Garcia, Emanuel; Kroon, Aart

    2014-01-01

    Principle Component Analysis (PCA) was performed on chemical data of two sediment cores from an urban fresh-water lake in Copenhagen, Denmark. X-ray fluorescence (XRF) core scanning provided the underlying datasets on 13 variables (Si, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Cd, Pb). Principle......, Fe, Rb) and characterized the content of minerogenic material in the sediment. In case of both cores, PC2 was a good descriptor emphasized as the contamination component. It showed strong linkages with heavy metals (Cu, Zn, Pb), disclosing changing heavy-metal contamination trends across different...

  7. Elemental analysis of air particulate samples in Jakarta area by x-ray fluorescence spectrometry

    Yumiarti; Yusuf, M.; Mellawati, June; Menry, Yulizon; Surtipanti S

    1998-01-01

    Determination of elements in air particulate samples collected from Jakarta, especially from industrial area Pulo Gadung, also from residence, office, and recreation sites had been carried out. The samples collected periodically from August through December 1996. The elements were analyzed by X-ray fluorescence spectrometry method. Quantitative and qualitative analyses were done using QXAS AXIL (Quantitative X-ray Analysis System of x-ray Spectra by Iterative Least squares fitting) and QAES (Quantitative Analyses of Environmental Samples) package program. Results of the analyses showed that the content of heavy metal elements in air particulate samples from all areas studied were still below the maximum permissible concentration. (authors)

  8. Elimination of matrix effect in quantitative analysis of elements using x-ray fluorescence

    Sampaio, R.V.

    1973-07-01

    The emission-transmission method of Leroux and Mahmud, an experimental technique for compensating matrix effects in photon excited X-ray fluorescence analysis, was used to determine the concentration of lead and antimony in pellets of galalith. The effect of interfering elements was studied by adding various concentrations of mercury and tin to the respective pellets. To illustrate possible environmental applications, a number of pellets was prepared from leaves of almond trees located in different regions of Rio de Janeiro. Lead concentrations were determined for the dried leaf material and showed values ranging from 50 to 145 parts per million [pt

  9. Analysis of zirconia and alumina products and raw materials by X-ray fluorescence spectrometry

    Boix, A.; Draignaud, M.; Debras-Guedon, J.

    1975-01-01

    An X-ray fluorescence spectrometric method of analysis for various raw materials and materials based on zirconia, alumina and silica was developed. The measurements were made on beads made from the sample and a borax based flux, in the proportions 1:10. A repeatability test allowed the relative standard deviation to be estimated for the three main constituents: SiO 2 , Al 2 O 3 , ZrO 2 : it is at the level of 1%. The element analyzed are: Si, Al, Fe, Ti, Ca, Hf and Zr [fr

  10. Fluorescence method for enzyme analysis which couples aromatic amines with aromatic aldehydes

    Smith, R.E.; Dolbeare, F.A.

    1980-10-21

    Analysis of proteinases is accomplished using conventional amino acid containing aromatic amine substrates. Aromatic amines such as 4-methoxy-2-naphthylamine (4M2NA), 2-naphthylamine, aminoisophthalic acid dimethyl ester, p-nitroaniline, 4-methoxy-1-aminofluorene and coumarin derivatives resulting from enzymatic hydrolysis of the substrate couples with aromatic aldehydes such as 5-nitrosalicylaldehyde (5-NSA), benzaldehyde and p-nitrobenzaldehyde to produce Schiff-base complexes which are water insoluble. Certain Schiff-base complexes produce a shift from blue to orange-red (visible) fluorescence. Such complexes are useful in the assay of enzymes. No Drawings

  11. The analysis, by a fusion procedure and X-ray-fluorescence spectrometry, of silicates and slags

    Jacobs, J.J.; Balaes, A.M.E.

    1980-01-01

    A glass-disc fusion method is described for the analysis, by X-ray-fluorescence spectrometry, of slags and silicate materials. The data are corrected for detector dead time and short-term instrumental drift. Corrections are made for matrix variations by use of the Lachange-Traill mathematical model, and the results are processed on a mini-computer, an iterative procedure being used in the solving of the simultaneous equations. As the alpha-correction coefficients of the Lachange-Traill model are not truly constant, a modified version of the model is proposed [af

  12. Determination of minor and trace elements in kidney stones by x-ray fluorescence analysis

    Srivastava, Anjali; Heisinger, Brianne J.; Sinha, Vaibhav; Lee, Hyong-Koo; Liu, Xin; Qu, Mingliang; Duan, Xinhui; Leng, Shuai; McCollough, Cynthia H.

    2014-03-01

    The determination of accurate material composition of a kidney stone is crucial for understanding the formation of the kidney stone as well as for preventive therapeutic strategies. Radiations probing instrumental activation analysis techniques are excellent tools for identification of involved materials present in the kidney stone. In particular, x-ray fluorescence (XRF) can be very useful for the determination of minor and trace materials in the kidney stone. The X-ray fluorescence measurements were performed at the Radiation Measurements and Spectroscopy Laboratory (RMSL) of department of nuclear engineering of Missouri University of Science and Technology and different kidney stones were acquired from the Mayo Clinic, Rochester, Minnesota. Presently, experimental studies in conjunction with analytical techniques were used to determine the exact composition of the kidney stone. A new type of experimental set-up was developed and utilized for XRF analysis of the kidney stone. The correlation of applied radiation source intensity, emission of X-ray spectrum from involving elements and absorption coefficient characteristics were analyzed. To verify the experimental results with analytical calculation, several sets of kidney stones were analyzed using XRF technique. The elements which were identified from this techniques are Silver (Ag), Arsenic (As), Bromine (Br), Chromium (Cr), Copper (Cu), Gallium (Ga), Germanium (Ge), Molybdenum (Mo), Niobium (Nb), Rubidium (Rb), Selenium (Se), Strontium (Sr), Yttrium (Y), Zirconium (Zr). This paper presents a new approach for exact detection of accurate material composition of kidney stone materials using XRF instrumental activation analysis technique.

  13. Enhancement of early cervical cancer diagnosis with epithelial layer analysis of fluorescence lifetime images.

    Jun Gu

    Full Text Available This work reports the use of layer analysis to aid the fluorescence lifetime diagnosis of cervical intraepithelial neoplasia (CIN from H&E stained cervical tissue sections. The mean and standard deviation of lifetimes in single region of interest (ROI of cervical epithelium were previously shown to correlate to the gold standard histopathological classification of early cervical cancer. These previously defined single ROIs were evenly divided into layers for analysis. A 10-layer model revealed a steady increase in fluorescence lifetime from the inner to the outer epithelial layers of healthy tissue sections, suggesting a close association with cellular maturity. The shorter lifetime and minimal lifetime increase towards the epithelial surface of CIN-affected regions are in good agreement with the absence of cellular maturation in CIN. Mean layer lifetimes in the top-half cervical epithelium were used as feature vectors for extreme learning machine (ELM classifier discriminations. It was found that the proposed layer analysis technique greatly improves the sensitivity and specificity to 94.6% and 84.3%, respectively, which can better supplement the traditional gold standard cervical histopathological examinations.

  14. Description of CORSET: a computer program for quantitative x-ray fluorescence analysis

    Stohl, F.V.

    1980-08-01

    Quantitative x-ray fluorescence analysis requires a method of correcting for absorption and secondary fluorescence effects due to the sample matrix. The computer program CORSET carries out these corrections without requiring a knowledge of the spectral distribution of the x-ray source, and only requires one standard per element or one standard containing all the elements. Sandia's version of CORSET has been divided into three separate programs to fit Sandia's specific requirements for on-line analysis in a melt facility. The melt facility is used to fabricate new alloys with very variable compositions and requires very rapid analyses during a run. Therefore, the standards must be analyzed several days in advance. Program DAT1 is used to set up a permanent file consisting of all the data related to the standards. Program UNINT is used to set up a permanent file with the intensities, background counts and counting times of the unknowns. Program CORSET uses the files created in UNINT and DAT1 to carry out the analysis. This report contains descriptions, listings, and sample runs for these programs. The accuracy of the analyses carried out with these three programs is about 1 to 2% relative with an elemental concentration of about 10 wt %

  15. Image segmentation and dynamic lineage analysis in single-cell fluorescence microscopy.

    Wang, Quanli; Niemi, Jarad; Tan, Chee-Meng; You, Lingchong; West, Mike

    2010-01-01

    An increasingly common component of studies in synthetic and systems biology is analysis of dynamics of gene expression at the single-cell level, a context that is heavily dependent on the use of time-lapse movies. Extracting quantitative data on the single-cell temporal dynamics from such movies remains a major challenge. Here, we describe novel methods for automating key steps in the analysis of single-cell, fluorescent images-segmentation and lineage reconstruction-to recognize and track individual cells over time. The automated analysis iteratively combines a set of extended morphological methods for segmentation, and uses a neighborhood-based scoring method for frame-to-frame lineage linking. Our studies with bacteria, budding yeast and human cells, demonstrate the portability and usability of these methods, whether using phase, bright field or fluorescent images. These examples also demonstrate the utility of our integrated approach in facilitating analyses of engineered and natural cellular networks in diverse settings. The automated methods are implemented in freely available, open-source software.

  16. Heavy metals analysis in fishes by the X-ray fluorescence method

    Perez Novara, Ana Ma.

    1986-04-01

    Among the sources of contamination in human beings we find ingestion of heavy metals. As it is common practice to pour industrial wastes in waters where fishes feed, some toxic elements present in water may pass to human beings through ingestion. It is therefore important to determine the concentrations of heavy metals present in fishes, mainly in those living in waters close to industrial zones or villages. Concentrations of heavy metals in tissue of fishes amount to ppm, hence making necessary the use of very sensitive analytical techniques which do not require a too complex preparation of the sample in order to avoid the loss or contamination of interesting elements of analysis while handling them, thus falsifying the results. The X-Ray Fluorescence method covers these requirements and is not destructive nor multi-elemental. The development of the technique of element analysis in fishes by X-Ray Fluorescence comprised several aspects. from sampling and storage to quantification, specially stressing the preparation of samples. The work was carried out with a Si-Li detector/monitor for solid state and associated electronic equipment. Cd-109 and Pu-238 sources were used to produce excitation, detection limits near 1 ppm were obtained in the majority of elements the technique attained for the analysis of this kind of samples fulfills the celerity, precision, accuracy, and sensitivity requirements. (author)

  17. Multi-elemental analysis of marine sediments of Sorsogon Bay using x-ray fluorescence spectroscopy

    Gonzales, Ralph Roly A.; Quirit, Leni L.; Rosales, Colleen Marciel F.; Pabroa, Preciosa Corazon B.; Sta Maria, Efren J.

    2011-01-01

    Metal composition and nutrient loadings of our bodies of water, when uncontrolled, may cause harmful bacterial contamination and pose threats in aquatic and human life. Toxic and trace element inputs in Sorsogon Bay sediments were determined using nuclear analytical techniques, more specifically, x-ray fluorescence spectrometry, in this study. Pre-treated marine sediment samples from Sorsogon Bay were homogenized using SPEX # 8000 mixer/mill and agate mortar and pestle, pelletized into 31-mm flat discs using SPEX 3630 X-Press and analyzed using PAN Analytical Epsilon 5 EDX X-ray Fluorescence Spectrometer with the emission and transmission method using silver and germanium secondary targets. Spectrum fitting performed using AXIL (Analysis of X-ray Spectra by Iterative Least-Squares Fitting), a subprogram in Quantitative X-ray Analysis System developed by the International Atomic Energy Agency and Quantitative Analysis of Environmental Samples program, was used for quantification of results. Results indicate generally moderate to high metal enrichment, specifically manganese, lead, cadmium, zinc and copper. Mercury and iron level enrichment are found to be low, marking an improvement from previous studies indicating high enrichment of these metals. (author)

  18. Complement Evasion by Pathogenic Leptospira.

    Fraga, Tatiana Rodrigues; Isaac, Lourdes; Barbosa, Angela Silva

    2016-01-01

    Leptospirosis is a neglected infectious disease caused by spirochetes from the genus Leptospira . Pathogenic microorganisms, notably those which reach the blood circulation such as Leptospira , have evolved multiple strategies to escape the host complement system, which is important for innate and acquired immunity. Leptospira avoid complement-mediated killing through: (i) recruitment of host complement regulators; (ii) acquisition of host proteases that cleave complement proteins on the bacterial surface; and, (iii) secretion of proteases that inactivate complement proteins in the Leptospira surroundings. The recruitment of host soluble complement regulatory proteins includes the acquisition of Factor H (FH) and FH-like-1 (alternative pathway), C4b-binding protein (C4BP) (classical and lectin pathways), and vitronectin (Vn) (terminal pathway). Once bound to the leptospiral surface, FH and C4BP retain cofactor activity of Factor I in the cleavage of C3b and C4b, respectively. Vn acquisition by leptospires may result in terminal pathway inhibition by blocking C9 polymerization. The second evasion mechanism lies in plasminogen (PLG) binding to the leptospiral surface. In the presence of host activators, PLG is converted to enzymatically active plasmin, which is able to degrade C3b, C4b, and C5 at the surface of the pathogen. A third strategy used by leptospires to escape from complement system is the active secretion of proteases. Pathogenic, but not saprophytic leptospires, are able to secrete metalloproteases that cleave C3 (central complement molecule), Factor B (alternative pathway), and C4 and C2 (classical and lectin pathways). The purpose of this review is to fully explore these complement evasion mechanisms, which act together to favor Leptospira survival and multiplication in the host.

  19. Characterization of DOM adsorption of CNTs by using excitation-emission matrix fluorescence spectroscopy and multiway analysis.

    Peng, Mingguo; Li, Huajie; Li, Dongdong; Du, Erdeng; Li, Zhihong

    2017-06-01

    Carbon nanotubes (CNTs) were utilized to adsorb DOM in micro-polluted water. The characteristics of DOM adsorption on CNTs were investigated based on UV 254 , TOC, and fluorescence spectrum measurements. Based on PARAFAC (parallel factor) analysis, four fluorescent components were extracted, including one protein-like component (C4) and three humic acid-like components (C1, C2, and C3). The adsorption isotherms, kinetics, and thermodynamics of DOM adsorption on CNTs were further investigated. A Freundlich isotherm model fit the adsorption data well with high values of correlation. As a type of macro-porous and meso-porous adsorbent, CNTs preferably adsorb humic acid-like substances rather than protein-like substances. The increasing temperature will speed up the adsorption process. The self-organizing map (SOM) analysis further explains the fluorescent properties of water samples. The results provide a new insight into the adsorption behaviour of DOM fluorescent components on CNTs.

  20. Analysis of the peptidoglycan hydrolase complement of Lactobacillus casei and characterization of the major γ-D-glutamyl-L-lysyl-endopeptidase.

    Regulski, Krzysztof; Courtin, Pascal; Meyrand, Mickael; Claes, Ingmar J J; Lebeer, Sarah; Vanderleyden, Jos; Hols, Pascal; Guillot, Alain; Chapot-Chartier, Marie-Pierre

    2012-01-01

    Peptidoglycan (PG) is the major component of Gram positive bacteria cell wall and is essential for bacterial integrity and shape. Bacteria synthesize PG hydrolases (PGHs) which are able to cleave bonds in their own PG and play major roles in PG remodelling required for bacterial growth and division. Our aim was to identify the main PGHs in Lactobacillus casei BL23, a lactic acid bacterium with probiotic properties.The PGH complement was first identified in silico by amino acid sequence similarity searches of the BL23 genome sequence. Thirteen PGHs were detected with different predicted hydrolytic specificities. Transcription of the genes was confirmed by RT-PCR. A proteomic analysis combining the use of SDS-PAGE and LC-MS/MS revealed the main seven PGHs synthesized during growth of L. casei BL23. Among these PGHs, LCABL_02770 (renamed Lc-p75) was identified as the major one. This protein is the homolog of p75 (Msp1) major secreted protein of Lactobacillus rhamnosus GG, which was shown to promote survival and growth of intestinal epithelial cells. We identified its hydrolytic specificity on PG and showed that it is a γ-D-glutamyl-L-lysyl-endopeptidase. It has a marked specificity towards PG tetrapeptide chains versus tripeptide chains and for oligomers rather than monomers. Immunofluorescence experiments demonstrated that Lc-p75 localizes at cell septa in agreement with its role in daughter cell separation. It is also secreted under an active form as detected in zymogram. Comparison of the muropeptide profiles of wild type and Lc-p75-negative mutant revealed a decrease of the amount of disaccharide-dipeptide in the mutant PG in agreement with Lc-p75 activity. As a conclusion, Lc-p75 is the major L. casei BL23 PGH with endopeptidase specificity and a key role in daughter cell separation. Further studies will aim at investigating the role of Lc-p75 in the anti-inflammatory potential of L. casei BL23.

  1. Analysis of the peptidoglycan hydrolase complement of Lactobacillus casei and characterization of the major γ-D-glutamyl-L-lysyl-endopeptidase.

    Krzysztof Regulski

    Full Text Available Peptidoglycan (PG is the major component of Gram positive bacteria cell wall and is essential for bacterial integrity and shape. Bacteria synthesize PG hydrolases (PGHs which are able to cleave bonds in their own PG and play major roles in PG remodelling required for bacterial growth and division. Our aim was to identify the main PGHs in Lactobacillus casei BL23, a lactic acid bacterium with probiotic properties.The PGH complement was first identified in silico by amino acid sequence similarity searches of the BL23 genome sequence. Thirteen PGHs were detected with different predicted hydrolytic specificities. Transcription of the genes was confirmed by RT-PCR. A proteomic analysis combining the use of SDS-PAGE and LC-MS/MS revealed the main seven PGHs synthesized during growth of L. casei BL23. Among these PGHs, LCABL_02770 (renamed Lc-p75 was identified as the major one. This protein is the homolog of p75 (Msp1 major secreted protein of Lactobacillus rhamnosus GG, which was shown to promote survival and growth of intestinal epithelial cells. We identified its hydrolytic specificity on PG and showed that it is a γ-D-glutamyl-L-lysyl-endopeptidase. It has a marked specificity towards PG tetrapeptide chains versus tripeptide chains and for oligomers rather than monomers. Immunofluorescence experiments demonstrated that Lc-p75 localizes at cell septa in agreement with its role in daughter cell separation. It is also secreted under an active form as detected in zymogram. Comparison of the muropeptide profiles of wild type and Lc-p75-negative mutant revealed a decrease of the amount of disaccharide-dipeptide in the mutant PG in agreement with Lc-p75 activity. As a conclusion, Lc-p75 is the major L. casei BL23 PGH with endopeptidase specificity and a key role in daughter cell separation. Further studies will aim at investigating the role of Lc-p75 in the anti-inflammatory potential of L. casei BL23.

  2. Quantitative fluorescence loss in photobleaching for analysis of protein transport and aggregation

    Wüstner Daniel

    2012-11-01

    Full Text Available Abstract Background Fluorescence loss in photobleaching (FLIP is a widely used imaging technique, which provides information about protein dynamics in various cellular regions. In FLIP, a small cellular region is repeatedly illuminated by an intense laser pulse, while images are taken with reduced laser power with a time lag between the bleaches. Despite its popularity, tools are lacking for quantitative analysis of FLIP experiments. Typically, the user defines regions of interest (ROIs for further analysis which is subjective and does not allow for comparing different cells and experimental settings. Results We present two complementary methods to detect and quantify protein transport and aggregation in living cells from FLIP image series. In the first approach, a stretched exponential (StrExp function is fitted to fluorescence loss (FL inside and outside the bleached region. We show by reaction–diffusion simulations, that the StrExp function can describe both, binding/barrier–limited and diffusion-limited FL kinetics. By pixel-wise regression of that function to FL kinetics of enhanced green fluorescent protein (eGFP, we determined in a user-unbiased manner from which cellular regions eGFP can be replenished in the bleached area. Spatial variation in the parameters calculated from the StrExp function allow for detecting diffusion barriers for eGFP in the nucleus and cytoplasm of living cells. Polyglutamine (polyQ disease proteins like mutant huntingtin (mtHtt can form large aggregates called inclusion bodies (IB’s. The second method combines single particle tracking with multi-compartment modelling of FL kinetics in moving IB’s to determine exchange rates of eGFP-tagged mtHtt protein (eGFP-mtHtt between aggregates and the cytoplasm. This method is self-calibrating since it relates the FL inside and outside the bleached regions. It makes it therefore possible to compare release kinetics of eGFP-mtHtt between different cells and

  3. Automated image analysis for quantitative fluorescence in situ hybridization with environmental samples.

    Zhou, Zhi; Pons, Marie Noëlle; Raskin, Lutgarde; Zilles, Julie L

    2007-05-01

    When fluorescence in situ hybridization (FISH) analyses are performed with complex environmental samples, difficulties related to the presence of microbial cell aggregates and nonuniform background fluorescence are often encountered. The objective of this study was to develop a robust and automated quantitative FISH method for complex environmental samples, such as manure and soil. The method and duration of sample dispersion were optimized to reduce the interference of cell aggregates. An automated image analysis program that detects cells from 4',6'-diamidino-2-phenylindole (DAPI) micrographs and extracts the maximum and mean fluorescence intensities for each cell from corresponding FISH images was developed with the software Visilog. Intensity thresholds were not consistent even for duplicate analyses, so alternative ways of classifying signals were investigated. In the resulting method, the intensity data were divided into clusters using fuzzy c-means clustering, and the resulting clusters were classified as target (positive) or nontarget (negative). A manual quality control confirmed this classification. With this method, 50.4, 72.1, and 64.9% of the cells in two swine manure samples and one soil sample, respectively, were positive as determined with a 16S rRNA-targeted bacterial probe (S-D-Bact-0338-a-A-18). Manual counting resulted in corresponding values of 52.3, 70.6, and 61.5%, respectively. In two swine manure samples and one soil sample 21.6, 12.3, and 2.5% of the cells were positive with an archaeal probe (S-D-Arch-0915-a-A-20), respectively. Manual counting resulted in corresponding values of 22.4, 14.0, and 2.9%, respectively. This automated method should facilitate quantitative analysis of FISH images for a variety of complex environmental samples.

  4. Methods for the analysis of complex fluorescence decays: sum of Becquerel functions versus sum of exponentials

    Menezes, Filipe; Fedorov, Alexander; Baleizão, Carlos; Berberan-Santos, Mário N; Valeur, Bernard

    2013-01-01

    Ensemble fluorescence decays are usually analyzed with a sum of exponentials. However, broad continuous distributions of lifetimes, either unimodal or multimodal, occur in many situations. A simple and flexible fitting function for these cases that encompasses the exponential is the Becquerel function. In this work, the applicability of the Becquerel function for the analysis of complex decays of several kinds is tested. For this purpose, decays of mixtures of four different fluorescence standards (binary, ternary and quaternary mixtures) are measured and analyzed. For binary and ternary mixtures, the expected sum of narrow distributions is well recovered from the Becquerel functions analysis, if the correct number of components is used. For ternary mixtures, however, satisfactory fits are also obtained with a number of Becquerel functions smaller than the true number of fluorophores in the mixture, at the expense of broadening the lifetime distributions of the fictitious components. The quaternary mixture studied is well fitted with both a sum of three exponentials and a sum of two Becquerel functions, showing the inevitable loss of information when the number of components is large. Decays of a fluorophore in a heterogeneous environment, known to be represented by unimodal and broad continuous distributions (as previously obtained by the maximum entropy method), are also measured and analyzed. It is concluded that these distributions can be recovered by the Becquerel function method with an accuracy similar to that of the much more complex maximum entropy method. It is also shown that the polar (or phasor) plot is not always helpful for ascertaining the degree (and kind) of complexity of a fluorescence decay. (paper)

  5. Synchrotron x-ray fluorescence and extended x-ray absorption fine structure analysis

    Chen, J.R.; Gordon, B.M.; Hanson, A.L.; Jones, K.W.; Kraner, H.W.; Chao, E.C.T.; Minkin, J.A.

    1984-01-01

    The advent of dedicated synchrotron radiation sources has led to a significant increase in activity in many areas of science dealing with the interaction of x-rays with matter. Synchrotron radiation provides intense, linearly polarized, naturally collimated, continuously tunable photon beams, which are used to determine not only the elemental composition of a complex, polyatomic, dilute material but also the chemical form of the elements with improved accuracy. Examples of the application of synchrotron radiation include experiments in synchrotron x-ray fluorescence (SXRF) analysis and extended x-ray absorption fine structure (EXAFS) analysis. New synchrotron radiation x-ray microprobes for elemental analysis in the parts per billion range are under construction at several laboratories. 76 references, 24 figures

  6. A method for the quantitative analysis of heavy elements by X-ray fluorescence

    Souza Caillaux, Z. de

    1981-01-01

    A study of quantitative analysis methodology by X-ray fluorescence analysis is presented. With no damage to precision it makes possible an analysis of heavy elements in samples with the form and texture as they present themselves. Some binary alloys were examined such as: FeCo; CuNi; CuZn; AgCd; AgPd; AuPt e PtIr. The possibility of application of this method is based on the compromise solutIon of wave lengths and the intensity of the homologous emission and absorption edges of constituents with the quantic efficiency of the detector, the dispersion and the wave lenght resolution of crystal analyser, and the uniformity of the excitation intensity. (Author) [pt

  7. Physical aspects of quantitative particles analysis by X-ray fluorescence and electron microprobe techniques

    Markowicz, A.

    1986-01-01

    The aim of this work is to present both physical fundamentals and recent advances in quantitative particles analysis by X-ray fluorescence (XRF) and electron microprobe (EPXMA) techniques. A method of correction for the particle-size effect in XRF analysis is described and theoretically evaluated. New atomic number- and absorption correction procedures in EPXMA of individual particles are proposed. The applicability of these two correction methods is evaluated for a wide range of elemental composition, X-ray energy and sample thickness. Also, a theoretical model for composition and thickness dependence of Bremsstrahlung background generated in multielement bulk specimens as well as thin films and particles are presented and experimantally evaluated. Finally, the limitations and further possible improvements in quantitative particles analysis by XFR and EPXMA are discussed. 109 refs. (author)

  8. Comparison of fluorescent tags for analysis of mannose-6-phosphate glycans.

    Kang, Ji-Yeon; Kwon, Ohsuk; Gil, Jin Young; Oh, Doo-Byoung

    2016-05-15

    Mannose-6-phosphate (M-6-P) glycan analysis is important for quality control of therapeutic enzymes for lysosomal storage diseases. Here, we found that the analysis of glycans containing two M-6-Ps was highly affected by the hydrophilicity of the elution solvent used in high-performance liquid chromatography (HPLC). In addition, the performances of three fluorescent tags--2-aminobenzoic acid (2-AA), 2-aminobenzamide (2-AB), and 3-(acetyl-amino)-6-aminoacridine (AA-Ac)--were compared with each other for M-6-P glycan analysis using HPLC and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The best performance for analyzing M-6-P glycans was shown by 2-AA labeling in both analyses. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. The fundamental parameter method applied to X-ray fluorescence analysis with synchrotron radiation

    Pantenburg, F. J.; Beier, T.; Hennrich, F.; Mommsen, H.

    1992-05-01

    Quantitative X-ray fluorescence analysis applying the fundamental parameter method is usually restricted to monochromatic excitation sources. It is shown here, that such analyses can be performed as well with a white synchrotron radiation spectrum. To determine absolute elemental concentration values it is necessary to know the spectral distribution of this spectrum. A newly designed and tested experimental setup, which uses the synchrotron radiation emitted from electrons in a bending magnet of ELSA (electron stretcher accelerator of the university of Bonn) is presented. The determination of the exciting spectrum, described by the given electron beam parameters, is limited due to uncertainties in the vertical electron beam size and divergence. We describe a method which allows us to determine the relative and absolute spectral distributions needed for accurate analysis. First test measurements of different alloys and standards of known composition demonstrate that it is possible to determine exact concentration values in bulk and trace element analysis.

  10. Elemental analysis of granite by instrumental neutron activation analysis (INAA) and X-ray fluorescence analysis (XRF)

    El-Taher, A.

    2012-01-01

    The instrumental neutron activation analysis technique (INAA) was used for qualitative and quantitative analysis of granite samples collected from four locations in the Aswan area in South Egypt. The samples were prepared together with their standards and simultaneously irradiated in a neutron flux of 7×10 11 n/cm 2 s in the TRIGA Mainz research reactor. Gamma-ray spectra from an hyper-pure germanium detector were analyzed. The present study provides the basic data of elemental concentrations of granite rocks. The following elements have been determined Na, Mg, K, Fe, Mn, Sc, Cr, Ti, Co, Zn, Ga, Rb, Zr, Nb, Sn, Ba, Cs, La, Ce, Nd, Sm, Eu, Yb, Lu, Hf, Ta, Th and U. The X-ray fluorescence (XRF) was used for comparison and to detect elements, which can be detected only by XRF such as F, S, Cl, Co, Cu, Mo, Ni, Pb, Se and V. The data presented here are our contribution to understanding the elemental composition of the granite rocks. Because there are no existing databases for the elemental analysis of granite, our results are a start to establishing a database for the Egyptian granite. It is hoped that the data presented here will be useful to those dealing with geochemistry, granite chemistry and related fields. - Highlights: ► Instrumental neutron activation analysis technique (INAA) was used for qualitative and quantitative analysis of granite. ► The samples were prepared together with their standards and simultaneously irradiated in a neutron flux of 7×10 11 n/cm 2 s in the TRIGA Mainz research reactor. ► Following elements have been determined Na, Mg, K, Fe, Mn, Sc, Cr, Ti, Co, Zn, Ga, Rb, Zr, Nb, Sn, Ba, Cs, La, Ce, Nd, Sm, Eu, Yb, Lu, Hf, Ta, Th and U.

  11. Rapid Simultaneous Amplification and Detection of the MBR/JH Chromosomal Translocation by Fluorescence Melting Curve Analysis

    Bohling, Sandra D.; King, Thomas C.; Wittwer, Carl T.; Elenitoba-Johnson, Kojo S. J.

    1999-01-01

    Polymerase chain reaction (PCR) amplification and product analysis for the detection of chromosomal translocations, such as the t(14;18), has traditionally been a two-step process. PCR product detection has generally entailed gel electrophoresis and/or hybridization or sequencing for confirmation of assay specificity. Using a microvolume fluorimeter integrated with a thermal cycler and a PCR-compatible double-stranded DNA (dsDNA) binding fluorescent dye (SYBR Green I), we investigated the feasibility of simultaneous thermal amplification and detection of MBR/JH translocation products by fluorescence melting curve analysis. We analyzed DNA from 30 cases of lymphoproliferative disorders comprising 19 cases of previously documented MBR/JH-positive follicle center lymphoma and 11 reactive lymphadenopathies. The samples were coded and analyzed blindly for the presence of MBR/JH translocations by fluorescence melting curve analysis. We also performed dilutional assays using the MBR/JH-positive cell line SUDHL-6. Multiplex PCR for MBR/JH and β-globin was used to simultaneously assess sample adequacy. All (100%) of the 19 cases previously determined to be MBR/JH positive by conventional PCR analysis showed a characteristic sharp decrease in fluorescence at ∼90°C by melting curve analysis after amplification. Fluorescence melting peaks obtained by plotting the negative derivative of fluorescence over temperature (−dF/dT) versus temperature (T) showed melting temperatures (Tm) at 88.85 ± 1.15°C. In addition, multiplex assays using both MBR/JH and β-globin primers yielded easily distinguishable fluorescence melting peaks at ∼90°C and 81.2°C, respectively. Dilutional assays revealed that fluorescence melting curve analysis was more sensitive than conventional PCR and agarose gel electrophoresis with ultraviolet transillumination by as much as 100-fold. Simultaneous amplification and fluorescence melting curve analysis is a simple, reliable, and sensitive method

  12. Development of image analysis for graphite pore-structure determination using fluorescence techniques

    Stephen, W.J.; Bowden, E.A.T.; Wickham, A.J.

    1983-03-01

    The use of image analysis to assess the pore structure of graphite has been developed to the point at which it may be considered available for routine use. A definitive pore structure in terms of the geometry-independent ''characteristic pore dimension'' is derived from the computer analysis of polished specimens whose open-pore structure has been impregnated with bismuth or a fluorescent epoxy resin, with the very small pores identified separately by mercury porosimetry as in the past. The pore-size distributions obtained from these combined techniques have been used successfully to predict the corrosion rates of nine graphites, of widely differing pore structure, in a variety of gas compositions and, indirectly, to confirm appropriate mean ranges and rate constants for the reaction of the oxidising species in these gas mixtures. The development of the fluorescent-impregnant technique is discussed in detail and its use is justified in preference to ''traditional'' methods. Further possible refinements are discussed, including the eventual aim of obtaining a computer prediction of the future oxidation behaviour of the graphite directly from the image analyser. (author)

  13. Precious metal assay analysis of fresh reforming catalyst by x-ray fluorescence spectrometry

    McElroy, F.C.; Mulhall, J.M.

    1991-01-01

    This paper reports that precious metal analysis of fresh reforming catalysts are typically performed by both the catalyst manufacturer and buyer to arrive at a financial settlement on the quantity of metal in each lot of commercial catalyst. Traditional assay methods involve a variety of fire assay or wet chemical acid digestion schemes coupled with gravimetric, colorimetic, or titrimetric measurement for precious metals. Methods must have sufficient precision and accuracy to afford interlaboratory agreement of within one half of one percent relative between the catalyst supplier and purchaser. To meet this requirement many laboratories rely on classical methods. Unfortunately these proceeders are labor intensive and time consuming. X-ray fluorescence has the inherent instrument precision to achieve typical intralaboratory precision of 0.5% RSD on a wide variety of elements and numerous sample types. We have developed an X-ray fluorescence method for the assay quality analysis of fresh reforming catalyst containing platinum, rhenium, and iridium. This method was applied to numerous samples over the past five years

  14. Contextual analysis of immunological response through whole-organ fluorescent imaging.

    Woodruff, Matthew C; Herndon, Caroline N; Heesters, B A; Carroll, Michael C

    2013-09-01

    As fluorescent microscopy has developed, significant insights have been gained into the establishment of immune response within secondary lymphoid organs, particularly in draining lymph nodes. While established techniques such as confocal imaging and intravital multi-photon microscopy have proven invaluable, they provide limited insight into the architectural and structural context in which these responses occur. To interrogate the role of the lymph node environment in immune response effectively, a new set of imaging tools taking into account broader architectural context must be implemented into emerging immunological questions. Using two different methods of whole-organ imaging, optical clearing and three-dimensional reconstruction of serially sectioned lymph nodes, fluorescent representations of whole lymph nodes can be acquired at cellular resolution. Using freely available post-processing tools, images of unlimited size and depth can be assembled into cohesive, contextual snapshots of immunological response. Through the implementation of robust iterative analysis techniques, these highly complex three-dimensional images can be objectified into sortable object data sets. These data can then be used to interrogate complex questions at the cellular level within the broader context of lymph node biology. By combining existing imaging technology with complex methods of sample preparation and capture, we have developed efficient systems for contextualizing immunological phenomena within lymphatic architecture. In combination with robust approaches to image analysis, these advances provide a path to integrating scientific understanding of basic lymphatic biology into the complex nature of immunological response.

  15. Preparation of uranium standard solutions for x-ray fluorescence analysis

    Wong, C.M.; Cate, J.L.; Pickles, W.L.

    1978-03-01

    A method has been developed for gravimetrically preparing uranium nitrate standards with an estimated mean error of 0.1% (1 sigma) and a maximum error of 0.2% (1 sigma) for the total uranium weight. Two source materials, depleted uranium dioxide powder and NBS Standard Reference Material 960 uranium metal, were used to prepare stock solutions. The NBS metal proved to be superior because of the small but inherent uncertainty in the stoichiometry of the uranium oxide. These solutions were used to prepare standards in a freeze-dried configuration suitable for x-ray fluorescence analysis. Both gravimetric and freeze-drying techniques are presented. Volumetric preparation was found to be unsatisfactory for 0.1% precision for the sample size of interest. One of the primary considerations in preparing uranium standards for x-ray fluorescence analysis is the development of a technique for dispensing a 50-μl aliquot of a standard solution with a precision of 0.1% and an accuracy of 0.1%. The method developed corrects for variation in aliquoting and for evaporation loss during weighing. Two sets, each containing 50 standards have been produced. One set has been retained by LLL and one set retained by the Savannah River project

  16. Principal component analysis of dynamic fluorescence images for diagnosis of diabetic vasculopathy

    Seo, Jihye; An, Yuri; Lee, Jungsul; Ku, Taeyun; Kang, Yujung; Ahn, Chulwoo; Choi, Chulhee

    2016-04-01

    Indocyanine green (ICG) fluorescence imaging has been clinically used for noninvasive visualizations of vascular structures. We have previously developed a diagnostic system based on dynamic ICG fluorescence imaging for sensitive detection of vascular disorders. However, because high-dimensional raw data were used, the analysis of the ICG dynamics proved difficult. We used principal component analysis (PCA) in this study to extract important elements without significant loss of information. We examined ICG spatiotemporal profiles and identified critical features related to vascular disorders. PCA time courses of the first three components showed a distinct pattern in diabetic patients. Among the major components, the second principal component (PC2) represented arterial-like features. The explained variance of PC2 in diabetic patients was significantly lower than in normal controls. To visualize the spatial pattern of PCs, pixels were mapped with red, green, and blue channels. The PC2 score showed an inverse pattern between normal controls and diabetic patients. We propose that PC2 can be used as a representative bioimaging marker for the screening of vascular diseases. It may also be useful in simple extractions of arterial-like features.

  17. Evaluation of ABS resin disk certified reference materials for heavy metal analysis by x-ray fluorescence analysis

    Ohata, Masaki; Kidokoro, Toshihiro; Kurahashi, Masayasu; Hioki, Akiharu

    2010-01-01

    ABS resin disk certified reference materials (CRMs) for heavy-metal analysis (NMIJ CRM 8105-a, NMIJ CRM 8106-a, NMIJ CRM 8115-a and NMIJ CRM 8116-a) were evaluated using an energy dispersive X-ray fluorescence (ED-XRF) analysis. The homogeneities of elements for both among-disks and within-disk were evaluated by ED-XRF analysis without any sample pre-treatment, which were similar to those evaluated by ICP-MS analysis after a sample digenstion procedure. The normalized XRF sensitivities for Cd, Cr and Pb in different ABS resin disk CRMs were compared, and the differences among them for those ABS resin disks that have similar matrices were observed. Moreover, Hg in those ABS resin disk CRMs was stable for long-term X-ray irradiation during ED-XRF analysis. (author)

  18. Threshold Analysis and Biodistribution of Fluorescently Labeled Bevacizumab in Human Breast Cancer

    Koch, Maximilian; de Jong, Johannes S.; Glatz, Juergen; Symvoulidis, Panagiotis; Lamberts, Laetitia E.; Adams, Arthur L. L.; Kranendonk, Mariette E. G.; Terwisscha Van Scheltinga, Anton; Aichler, Michaela; Jansen, Liesbeth; de Vries, Jakob; Lub-de Hooge, Marjolijn N.; Schroder, Carolien P.; Jorritsma-Smit, Annelies; Linssen, Matthijs D.; de Boer, Esther; van der Vegt, Bert; Nagengast, Wouter B.; Elias, Sjoerd G.; Oliveira, Sabrina; Witkamp, Arjen J.; Mali, Willem P. T. M.; Van der Wall, Elsken; Garcia-Allende, P. Beatriz; van Diest, Paul J.; de Vries, Elisabeth G. E.; Walch, Axel; van Dam, Gooitzen M.; Ntziachristos, Vasilis

    2017-01-01

    In vivo tumor labeling with fluorescent agents may assist endoscopic and surgical guidance for cancer therapy as well as create opportunities to directly observe cancer biology in patients. However, malignant andnonmalignant tissues are usually distinguished on fluorescence images by applying

  19. Complementing approaches to demonstrate chlorinated solvent biodegradation in a complex pollution plume: Mass balance, PCR and compound-specific stable isotope analysis

    Courbet, Christelle; Rivière, Agnès; Jeannottat, Simon; Rinaldi, Sandro; Hunkeler, Daniel; Bendjoudi, Hocine; de Marsily, Ghislain

    2011-11-01

    This work describes the use of different complementing methods (mass balance, polymerase chain reaction assays and compound-specific stable isotope analysis) to demonstrate the existence and effectiveness of biodegradation of chlorinated solvents in an alluvial aquifer. The solvent-contaminated site is an old chemical factory located in an alluvial plain in France. As most of the chlorinated contaminants currently found in the groundwater at this site were produced by local industries at various times in the past, it is not enough to analyze chlorinated solvent concentrations along a flow path to convincingly demonstrate biodegradation. Moreover, only a few data were initially available to characterize the geochemical conditions at this site, which were apparently complex at the source zone due to (i) the presence of a steady oxygen supply to the groundwater by irrigation canal losses and river infiltration and (ii) an alkaline pH higher than 10 due to former underground lime disposal. A demonstration of the existence of biodegradation processes was however required by the regulatory authority within a timeframe that did not allow a full geochemical characterization of such a complex site. Thus a combination of different fast methods was used to obtain a proof of the biodegradation occurrence. First, a mass balance analysis was performed which revealed the existence of a strong natural attenuation process (biodegradation, volatilization or dilution), despite the huge uncertainty on these calculations. Second, a good agreement was found between carbon isotopic measurements and PCR assays (based on 16S RNA gene sequences and functional genes), which clearly indicated reductive dechlorination of different hydrocarbons (Tetrachloroethene—PCE-, Trichloroethene—TCE-, 1,2- cisDichloroethene— cis-1,2-DCE-, 1,2- transDichloroethene— trans-1,2-DCE-, 1,1-Dichloroethene—1,1-DCE-, and Vinyl Chloride—VC) to ethene. According to these carbon isotope measurements

  20. Statistical Analysis of Bending Rigidity Coefficient Determined Using Fluorescence-Based Flicker-Noise Spectroscopy.

    Doskocz, Joanna; Drabik, Dominik; Chodaczek, Grzegorz; Przybyło, Magdalena; Langner, Marek

    2018-06-01

    Bending rigidity coefficient describes propensity of a lipid bilayer to deform. In order to measure the parameter experimentally using flickering noise spectroscopy, the microscopic imaging is required, which necessitates the application of giant unilamellar vesicles (GUV) lipid bilayer model. The major difficulty associated with the application of the model is the statistical character of GUV population with respect to their size and the homogeneity of lipid bilayer composition, if a mixture of lipids is used. In the paper, the bending rigidity coefficient was measured using the fluorescence-enhanced flicker-noise spectroscopy. In the paper, the bending rigidity coefficient was determined for large populations of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-sn-glycero-3-phosphocholine vesicles. The quantity of obtained experimental data allows to perform statistical analysis aiming at the identification of the distribution, which is the most appropriate for the calculation of the value of the membrane bending rigidity coefficient. It has been demonstrated that the bending rigidity coefficient is characterized by an asymmetrical distribution, which is well approximated with the gamma distribution. Since there are no biophysical reasons for that we propose to use the difference between normal and gamma fits as a measure of the homogeneity of vesicle population. In addition, the effect of a fluorescent label and types of instrumental setups on determined values has been tested. Obtained results show that the value of the bending rigidity coefficient does not depend on the type of a fluorescent label nor on the type of microscope used.

  1. Analysis of Single-cell Gene Transcription by RNA Fluorescent In Situ Hybridization (FISH)

    Ronander, Elena; Bengtsson, Dominique C; Joergensen, Louise

    2012-01-01

    Adhesion of Plasmodium falciparum infected erythrocytes (IE) to human endothelial receptors during malaria infections is mediated by expression of PfEMP1 protein variants encoded by the var genes. The haploid P. falciparum genome harbors approximately 60 different var genes of which only one has...... been believed to be transcribed per cell at a time during the blood stage of the infection. How such mutually exclusive regulation of var gene transcription is achieved is unclear, as is the identification of individual var genes or sub-groups of var genes associated with different receptors...... fluorescent in situ hybridization (FISH) analysis of var gene transcription by the parasite in individual nuclei of P. falciparum IE(1). Here, we present a detailed protocol for carrying out the RNA-FISH methodology for analysis of var gene transcription in single-nuclei of P. falciparum infected human...

  2. Colouration of medieval glass bracelets studied by total reflection x-ray fluorescence analysis

    Detcheva, Albena; Velinova, Ralitsa; Ivanova, Elisaveta; Jordanov, Juri; Karadjov, Metody

    2014-01-01

    The contents of 3d-transition metals (Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) in fragments of medieval glass bracelets, found in the necropolis of Stambolovo and the castle of Mezek, Bulgaria, were determined by total reflection X-ray fluorescence (TXRF) analysis using gallium as internal standard. The samples were analysed as slurries in Triton X 114. The experimental parameters: grain size of the glass sample, concentrations of glass sample, Triton X114 and internal standard in the slurry, volume of the slurry aliquot taken for analysis, as well as the excitation time, were optimised. For method validation the certified reference material BAM-S005 Type A soda-lime glass was used. It was proven that the elements Co, Mn and Fe are responsible for colour generation in the investigated glass samples. The precision of the determinations is characterised by an RSD in the range 3–11%

  3. Energy-dispersive X-ray fluorescence analysis of organic-rich soils and sediments

    Parekh, P.P.

    1981-01-01

    A method has been developed for elemental analysis of environmental samples of soils and sediments rich in organic matter by energy-dispersive X-ray fluorescence spectrometry. It consists of three steps (i) determining the apparent concentration of elements by using calibration coefficients based on geochemical standards, (ii) subsequent assay of the total organic matter (TOM) from loss on ignition at 550 deg C, and (iii) evaluating the correct elemental concentration by normalizing for transparency from an empirical relationship. The main feature of the method is the sample analysis prior to ignition, which avoids any loss of trace elements - especially the volatile toxic elements, such as Zn, As, Se, and Pb - during heating. The method was tested on two organic-rich lake sediments (TOM> 30%). Concentrations of five elements (K, Mn, Fe, Zn, and Pb) determined by the present method and by atomic absorption spectrometry agreed within about +-10%. (author)

  4. Development of a combined portable x-ray fluorescence and Raman spectrometer for in situ analysis.

    Guerra, M; Longelin, S; Pessanha, S; Manso, M; Carvalho, M L

    2014-06-01

    In this work, we have built a portable X-ray fluorescence (XRF) spectrometer in a planar configuration coupled to a Raman head and a digital optical microscope, for in situ analysis. Several geometries for the XRF apparatus and digital microscope are possible in order to overcome spatial constraints and provide better measurement conditions. With this combined spectrometer, we are now able to perform XRF and Raman measurements in the same point without the need for sample collection, which can be crucial when dealing with cultural heritage objects, as well as forensic analysis. We show the capabilities of the spectrometer by measuring several standard reference materials, as well as other samples usually encountered in cultural heritage, geological, as well as biomedical studies.

  5. Diagnostic and Prognostic Utility of Fluorescence In situ Hybridization (FISH) Analysis in Acute Myeloid Leukemia.

    Gonzales, Patrick R; Mikhail, Fady M

    2017-12-01

    Acute myeloid leukemia (AML) is a hematologic neoplasia consisting of incompletely differentiated hematopoietic cells of the myeloid lineage that proliferate in the bone marrow, blood, and/or other tissues. Clinical implementation of fluorescence in situ hybridization (FISH) in cytogenetic laboratories allows for high-resolution analysis of recurrent structural chromosomal rearrangements specific to AML, especially in AML with normal karyotypes, which comprises approximately 33-50% of AML-positive specimens. Here, we review the use of several FISH probe strategies in the diagnosis of AML. We also review the standards and guidelines currently in place for use by clinical cytogenetic laboratories in the evaluation of AML. Updated standards and guidelines from the WHO, ACMG, and NCCN have further defined clinically significant, recurring cytogenetic anomalies in AML that are detectable by FISH. FISH continues to be a powerful technique in the diagnosis of AML, with higher resolution than conventional cytogenetic analysis, rapid turnaround time, and a considerable diagnostic and prognostic utility.

  6. Quantitative X-ray fluorescence analysis at the ESRF ID18F microprobe

    Vekemans, B; Somogyi, A; Drakopoulos, M; Kempenaers, L; Simionovici, A; Adams, F

    2003-01-01

    The new ID18F end-station at the European synchrotron radiation facility (ESRF) in Grenoble (France) is dedicated to sensitive and accurate quantitative micro-X-ray fluorescence (XRF) analysis at the ppm level with accuracy better than 10% for elements with atomic numbers above 18. For accurate quantitative analysis, given a high level of instrumental stability, major steps are the extraction and conversion of experimental X-ray line intensities into elemental concentrations. For this purpose a two-step quantification approach was adopted. In the first step, the collected XRF spectra are deconvoluted on the basis of a non-linear least-squares fitting algorithm (AXIL). The extracted characteristic line intensities are then used as input for a detailed Monte Carlo (MC) simulation code dedicated to XRF spectroscopy taking into account specific experimental conditions (excitation/detection) as well as sample characteristics (absorption and enhancement effects, sample topology, heterogeneity etc.). The iterative u...

  7. Identification and characterization of historical pigments with x-ray diffraction analysis (XRD), x-ray fluorescence analysis (XRA) and Fourier transformed infrared spectroscopy (FTIR)

    Hochleitner, B.

    2002-11-01

    This thesis presents a systematic characterization of historical inorganic pigments with respect to their crystallographic structure, main components, and trade elements, utilizing three complementary methods. The results are compiled in a computer-database containing the experimentally obtained information. The specimens examined in this study originate from a collection of 19th and 20th century pigments, dyes and binders with a wide variety of colors and materials at the Institute of Natural Sciences and Technologies in Art of the Academy of Fine Arts in Vienna. Approximately 400 different inorganic pigments were analysed for this first study of its kind by combining the experimental techniques explained in the next paragraph. For analyzing the inorganic pigments three different methods were applied: x-ray diffraction (XRD), x-ray fluorescence (XRF) and fourier-transformed infrared spectroscopy (FTIR) proved to be suitable techniques to identify and characterize the composition of the materials. The experimental work was focused on x-ray diffraction to detect the main components and to perform phase analysis for the identification of the crystallographic structure. To facilitate the analysis of the diffractograms and investigate differences in the elemental composition, XRF-measurements were carried out and complemented by FTIR-spectroscopy. The latter technique supports the identification of organic components of the samples and both ease phase analysis. In some cases, the obtained results show remarkable differences in composition for pigments having the same trade name. These differences consist either with respect to the identified elements or added components, such as pure white pigments. However, in most cases the chemical structure of the phase determining the color of the relevant pigment group was similar. Knowledge of the composition of the originally used pigments is of great importance for the restoration and conservation of art objects. In order to

  8. Brownian motion of polyphosphate complexes in yeast vacuoles: characterization by fluorescence microscopy with image analysis.

    Puchkov, Evgeny O

    2010-06-01

    In the vacuoles of Saccharomyces cerevisiae yeast cells, vividly moving insoluble polyphosphate complexes (IPCs) movement of the IPCs and to evaluate the viscosity in the vacuoles using the obtained data. Studies were conducted on S. cerevisiae cells stained by DAPI and fluorescein isothyocyanate-labelled latex microspheres, using fluorescence microscopy combined with computer image analysis (ImageJ software, NIH, USA). IPC movement was photorecorded and shown to be Brownian motion. On latex microspheres, a methodology was developed for measuring a fluorescing particle's two-dimensional (2D) displacements and its size. In four yeast cells, the 2D displacements and sizes of the IPCs were evaluated. Apparent viscosity values in the vacuoles of the cells, computed by the Einstein-Smoluchowski equation using the obtained data, were found to be 2.16 +/- 0.60, 2.52 +/- 0.63, 3.32 +/- 0.9 and 11.3 +/- 1.7 cP. The first three viscosity values correspond to 30-40% glycerol solutions. The viscosity value of 11.3 +/- 1.7 cP was supposed to be an overestimation, caused by the peculiarities of the vacuole structure and/or volume in this particular cell. This conclusion was supported by the particular quality of the Brownian motion trajectories set in this cell as compared to the other three cells.

  9. Estimation of the number of fluorescent end-members for quantitative analysis of multispectral FLIM data.

    Gutierrez-Navarro, Omar; Campos-Delgado, Daniel U; Arce-Santana, Edgar R; Maitland, Kristen C; Cheng, Shuna; Jabbour, Joey; Malik, Bilal; Cuenca, Rodrigo; Jo, Javier A

    2014-05-19

    Multispectral fluorescence lifetime imaging (m-FLIM) can potentially allow identifying the endogenous fluorophores present in biological tissue. Quantitative description of such data requires estimating the number of components in the sample, their characteristic fluorescent decays, and their relative contributions or abundances. Unfortunately, this inverse problem usually requires prior knowledge about the data, which is seldom available in biomedical applications. This work presents a new methodology to estimate the number of potential endogenous fluorophores present in biological tissue samples from time-domain m-FLIM data. Furthermore, a completely blind linear unmixing algorithm is proposed. The method was validated using both synthetic and experimental m-FLIM data. The experimental m-FLIM data include in-vivo measurements from healthy and cancerous hamster cheek-pouch epithelial tissue, and ex-vivo measurements from human coronary atherosclerotic plaques. The analysis of m-FLIM data from in-vivo hamster oral mucosa identified healthy from precancerous lesions, based on the relative concentration of their characteristic fluorophores. The algorithm also provided a better description of atherosclerotic plaques in term of their endogenous fluorophores. These results demonstrate the potential of this methodology to provide quantitative description of tissue biochemical composition.

  10. Quantitative analysis of thorium in the presence of rare earth by X-ray fluorescence spectrometry

    Jesus, Camila S. de; Taam, Isabel; Vianna, Claudio A.

    2013-01-01

    The occurrence of Thorium in ores is normally associated to other elements such as Uranium and Cerium, as well as some Rare-Earths (RE). The separation of these elements by traditional analytic chemistry techniques is both time and reagent consuming, thus increasing the analysis cost. The hereby proposed method consists in the direct determination of Thorium in rare earths ores and compounds by X-ray fluorescence spectroscopy without any prior chemical separation from other matrix elements. This non-destructive technique is used to determine which elements are present in solid and liquid samples, as well as their concentrations. The studied matrix contains Lanthanum, Cerium, Praseodymium, Neodymium, Samarium, Gadolinium and Yttrium. This study evaluated the analytical lines of radiation emission for each rare earth contained in the matrix, comparing it to the Thorium main analytical line. The Thorium quantification was measured through the Th L line, where there is no influence or interference from the rare earths analytical lines. The studied samples are certified standards and the obtained results have been compared to Ethylenediaminetetraacetic acid (EDTA) titration results, an already well-established and widely trusted method. We also measured the matrix effect thus using complex rare earths liquor. This liquor contains also elements commonly found in monazites sands: phosphates, aluminum, iron. Obtained results state the efficiency of X-ray Fluorescence to determine Thorium in the presence of rare earths without any prior chemical separation. (author)

  11. Elemental concentration analysis in prostate tissues using total reflection X-ray fluorescence

    Leitão, R.G.; Palumbo, A.; Souza, P.A.V.R.; Pereira, G.R.; Canellas, C.G.L.; Anjos, M.J.; Nasciutti, L.E.; Lopes, R.T.

    2014-01-01

    Prostate cancer (PCa) currently represents the second most prevalent malignant neoplasia in men, representing 21% of all cancer cases. Benign Prostate Hyperplasia (BPH) is an illness prevailing in men above the age of 50, close to 90% after the age of 80. The prostate presents a high zinc concentration, about 10-fold higher than any other body tissue. In this work, samples of human prostate tissues with cancer, BPH and normal tissue were analyzed utilizing total reflection X-ray fluorescence spectroscopy using synchrotron radiation technique (SR-TXRF) to investigate the differences in the elemental concentrations in these tissues. SR-TXRF analyses were performed at the X-ray fluorescence beamline at Brazilian National Synchrotron Light Laboratory (LNLS), in Campinas, São Paulo. It was possible to determine the concentrations of the following elements: P, S, K, Ca, Fe, Cu, Zn and Rb. By using Mann–Whitney U test it was observed that almost all elements presented concentrations with significant differences (α=0.05) between the groups studied. - Highlights: ► Prostate cancer is the most frequently diagnosed form of cancer in men. ► Intracellular Zn is correlated with proliferation, differentiation, or apoptosis. ► The prostate gland accumulate high concentration of Zn. ► SR-TXRF is a technique widely used in the analysis of low concentration in samples

  12. Multielemental analysis in cigarettes using total reflection X-ray fluorescence with synchrotron radiation

    Barbosa, R.F.; Anjos, M.J. dos; Jesus, E.F.O. de; Lopes, R.T.; Moreira, S.

    2008-01-01

    Full text: It is well known that trace elements have important ejects in the life processes. Some of these elements are toxic for the human even at a very low level of intake. It is known that tobacco plant easily absorbs the heavy metals from the soil, especially Cd and Ni, accumulating them in its leaves. Part of these metals are transferred from tobacco to human body where they will be accumulated and damage some organs, mainly kidneys and liver. In this way, cigarettes are responsible for the death of millions of people in the world, about one death every eight seconds. The aim of this work was to determine the elemental concentrations of ten different elements in tobacco of Brazilian cigarettes used Total Reflection X-Ray Fluorescence with Synchrotron Radiation method. The fluorescence measurements were carried out at Brazilian Synchrotron Light Laboratory, Campinas - Sao Paulo. A qualitative analysis of spectral peaks showed that the samples contained potassium, calcium, titanium, chromium, manganese, iron, copper, rubidium and strontium. Among these elements, calcium, potassium and iron presented the highest concentrations. There was a wide range in the elemental concentrations in the tobacco, due various factors, such as agricultural practices, soil characteristics, climatic conditions and plant varieties. Our results are in good concern with the results reported by the scientific literature

  13. Genetic analysis of complement C1s deficiency associated with systemic lupus erythematosus highlights alternative splicing of normal C1s gene

    Amano, Mariane T; Ferriani, Virgínia P L; Florido, Marlene P C

    2008-01-01

    Deficiencies of complement proteins of the classical pathway are strongly associated with the development of autoimmune diseases. Deficiency of C1r has been observed to occur concomitantly with deficiency in C1s and 9 out of 15 reported cases presented systemic lupus erythematosus (SLE). Here, we...... describe a family in which all four children are deficient in C1s but only two of them developed SLE. Hemolytic activity mediated by the alternative and the lectin pathways were normal, but classical pathway activation was absent in all children's sera. C1s was undetectable, while in the parents' sera...

  14. Application of x-ray fluorescence (XRF) absolute analysis method for silica refractories

    Asakura, Hideo; Yamada, Yasujiro; Kansai, Kouhei; Tomatsu, Ichirou; Murata, Mamoru

    2015-01-01

    X-ray fluorescence (XRF) analysis is a rapid and precise quantitative analytical method for the determination of major and trace elements in many industries and academics. XRF analytical values are relative due to the use of the calibration curves calculated from measuring the reference standard materials such as Japanese Refractory Reference Materials (JRRM) series with certified values determined by wet chemical analysis. The development of the XRF analytical method from relative to absolute analysis will help much to determine the absolute values of samples from the fields where reference standard samples have not been prepared, and thus can be applied widely in many industries. The implement of the absolute XRF analysis for silica refractories requires high purity reagents and/or reference standard solution for the binary basic calibration curve, and theoretical matrix correction coefficients for the multi-components silica refractories analysis. The reproducibility and repeatability of this method for Al 2 O 3 5 mass% sample were 0.009 and 0.006 mass% in Al 2 O 3 and showed better values that those of ICP-AES recognized as an absolute method in JIS R 2212-2, which yielded 0.028 and 0.031 mass%, respectively. The XRF absolute analysis for JRRM 200 series, 201a and 205a does not show a bias but coincides with their certified values. (author)

  15. Complement fixation test to C burnetii

    ... complement fixation test; Coxiella burnetii - complement fixation test; C burnetii - complement fixation test ... a specific foreign substance ( antigen ), in this case, C burnetii . Antibodies defend the body against bacteria, viruses, ...

  16. Synchrotron radiation total reflection x-ray fluorescence analysis; of polymer coated silicon wafers

    Brehm, L.; Kregsamer, P.; Pianetta, P.

    2000-01-01

    It is well known that total reflection x-ray fluorescence (TXRF) provides an efficient method for analyzing trace metal contamination on silicon wafer surfaces. New polymeric materials used as interlayer dielectrics in microprocessors are applied to the surface of silicon wafers by a spin-coating process. Analysis of these polymer coated wafers present a new challenge for TXRF analysis. Polymer solutions are typically analyzed for bulk metal contamination prior to application on the wafer using inductively coupled plasma mass spectrometry (ICP-MS). Questions have arisen about how to relate results of surface contamination analysis (TXRF) of a polymer coated wafer to bulk trace analysis (ICP-MS) of the polymer solutions. Experiments were done to explore this issue using synchrotron radiation (SR) TXRF. Polymer solutions were spiked with several different concentrations of metals. These solutions were applied to silicon wafers using the normal spin-coating process. The polymer coated wafers were then measured using the SR-TXRF instrument set-up at the Stanford Synchrotron Radiation Laboratory (SSRL). Several methods of quantitation were evaluated. The best results were obtained by developing calibration curves (intensity versus ppb) using the spiked polymer coated wafers as standards. Conversion of SR-TXRF surface analysis results (atoms/cm 2 ) to a volume related concentration was also investigated. (author)

  17. Force Dynamics of Verb Complementation

    Jacek Woźny

    2015-12-01

    Full Text Available Force Dynamics of Verb Complementation The concepts of motion and force are both extensively discussed in cognitive linguistics literature. But they are discussed separately. The first usually in the context of ‘motion situations’ (Talmy, Slobin, Zlatev, the other as part of the Force Dynamics framework, which was developed by Talmy. The aim of this paper is twofold: first, to argue that the concepts of force and motion should not be isolated but considered as two inseparable parts of force-motion events. The second goal is to prove that the modified Force Dynamics (force-motion framework can be used for precise characterization of the verb complementation patterns. To this end, a random sample of 50 sentences containing the verb ‘went’ is analyzed, demonstrating the differences between the categories of intensive and intransitive complementation with respect to the linguistically coded parameters of force and motion.

  18. Account of spectral dependence of instrumental factor in quantitative X-ray fluorescence analysis

    Pershin, N.V.; Mosichev, V.I.

    1990-01-01

    A new method for calibration of X-ray fluorescence spectrometers using scanning spectrometric channel is proposed. The method is based on a separate account of matrix and instrumental effects and needs no calibration standards for the element analysed. For calibration in the whole spectral range of XRS (0.03-1.0 nm) it is sufficient to have from 10 to 15 pure element emitters made of most wide spread elements. The method provides rapid development of quantitative analysis for the elements which are not provided with standard samples and preparation of pure element emitters for which is impossible or problematic. The practical verification of the method was made by analysing a set of 146 standard samples covering a wide group of alloys. The mean relative error of the method was 3-5 % in an analytical range of 0.1-3.0 wt %

  19. Procedure of trace element analysis in oyster tissues by using X-ray fluorescence

    Vo Thi Tuong Hanh; Dinh Thi Bich Lieu; Dinh Thien Lam and Nguyen Manh Hung

    2004-01-01

    The procedure of trace element analysis such as Ca, Mn, Fe, Zn, Cu, Pb in molluscs (oyster tissues) was established by using X-ray fluorescence techniques. The procedure was investigated from the sample collection, drying, ashing ratio to the analytical techniques by using Cd-109, detector Si (Li) and the peak processing MCAPLUS program was applied for this study. The procedure is based on direct comparison with certified concentrations of international standard reference SRM 1566b Oyster Tissue of National Institute of Standards and Technology, Department of commerce, United States of America for Ca, Mn, Fe, Zn, Cu and the Standard Addition Methods for Pb. The accuracy of the Standard Addition Methods was estimated by CRM281 Rye Grass of Community Bureau of Reference-BCR, European Commission. The results of 10 samples which were collected from several markets in Hanoi are shown. (author)

  20. Metals determination in coffee sample by total reflection X-ray fluorescence analysis (TXRF)

    Vives, Ana Elisa Sirito de

    2005-01-01

    The objective of this study was to evaluate the inorganic concentration in five brands of coffee, three of them nationally marketed and the others of an exportation kind. The samples were prepared by infusion with deionized water. To carry out the calibration, standard solutions were prepared with different concentrations of Al, Si, K, Ca, Ti, Cr, Fe, Ni, Zn and Se. The measurements were carried out using a white beam of synchrotron radiation for excitation and a Si (Li) semiconductor detector for detection. By employing Synchrotron Radiation Total Reflection X-Ray Fluorescence Analysis (SR-TXRF) it was possible to evaluate the concentrations of P, S, Cl, K, Ca, Mn, Fe, Cu, Zn, Rb and Ba. The detection limits for 300 s counting time were in the range of 0.03 (Ca) to 30 ng.g -1 (Rb), respectively. (author)

  1. Evaluation of diatomea algae Thalassiosira weissflogii sensitivity to chloride mercury and methylmercury by chlorophyll fluorescence analysis

    Graevskaya, E. E.; Antal, T. K.; Matorin, D. N.; Voronova, E. N.; Pogosyan, S. I.; Rubin, A. B.

    2003-05-01

    Measurement of chlorophyll fluorescence has been shown to be a rapid, non-invasive, and reliable method to assess photosynthetic performance in a changing environment. In our study, the pulseamplitude-modulation (PAM) - fluorometric method was used to evaluate the sensitivity to chloride mercury and methylmercury chloride of diatomea microalgae Thalassiosira weissflogii. We found that 10^{-6} and 10^{-7} M MeHg led to a slow decrease in the PS II activity following for prolonged lag phase, whereas the algae was not sensitive to the same concentrations of HgCl2. However observed PS II inactivation by methylmercury was not complete and about 10 percents ofthe cells kept the high level of PS II activity as it was shown by microfluorometric analysis. These cells could determine adaptation of algae to methylmercury effect. Both toxicants decreased the rate of PS II reparation, as well as increased a heat pathway of excitation dissipation in PS II antennae complex.

  2. Metals determination in wood treated by synchrotron radiation X-ray fluorescence analysis

    Vives, Ana Elisa Sirito de; Medeiros, Jean Gabriel da Silva; Tomazello Filho, Mario

    2005-01-01

    The paper describes the use of X-Ray fluorescence analysis for distribution and quantification of metals in the hardwood (Eucalyptus sp) and softwood (Pinus sp) treated with CCA (copper-chromium-arsenic). The sapwood/heartwood for hardwood sample and the growth-rings for softwood sample were analyzed. The samples were scanned in 320 mm steps in the vertical direction. For excitation of the elements a white beam synchrotron radiation of ∼ 320 x 180 mm was employed and for the X-ray detection a Si(Li) semiconductor detector. The elements K, Ca, Cr, Mn, Cu, Zn and As were determined. Fundamental parameters were used to quantify the elements concentrations. (author)

  3. 2-Pyridylfuran: a new fluorescent tag for the analysis of carbohydrates.

    Cai, Zhi Peng; Hagan, Andrew Kevin; Wang, Mao Mao; Flitsch, Sabine Lahja; Liu, Li; Voglmeir, Josef

    2014-05-20

    We herein report the use of 1,3-di(2-pyridyl)-1,3-propanedione (DPPD) as a fluorogenic labeling reagent for sugars. Reaction of DPPD with the anomeric carbon affords a fluorescent 2-pyridylfuran (2-PF) moiety that permits the sensitive HPLC-based detection of monosaccharides. 2-PF-labeled monosaccharides can be easily separated and analyzed from mixtures thereof, and the reported protocol compares favorably with established labeling reagents such as 2-aminobenzoic acid (2-AA) and 1-phenyl-3-methyl-5-pyrazolone (PMP), ultimately allowing subfemtomole detection of the galactose-derived product. Furthermore, we demonstrate the application of DPPD in the labeling of monosaccharides in complex biological matrices such as blood and milk samples. We envisage that DPPD will prove to be an excellent choice of labeling reagent in monosaccharide and carbohydrate analysis.

  4. Metals determination in coffee sample by total reflection X-ray fluorescence analysis (TXRF)

    Vives, Ana Elisa Sirito de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo]. E-mail: Silvana@fec.unicamp.br; Brienza, Sandra Maria Boscolo [ Universidade Metodista de Piracicaba (UNIMEP), Piracicaba, SP (Brazil). Faculdade de Ciencias Matematicas, da Natureza e de Tecnologia da Informacao]. E-mail: sbrienza@unimep.br; Zucchi, Orgheda Luiza Araujo Domingues [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: olzucchi@fcfrp.usp.br; Nascimento Filho, Virgilio Franco do [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil)]. E-mail: virgilio@cena.usp.br

    2005-07-01

    The objective of this study was to evaluate the inorganic concentration in five brands of coffee, three of them nationally marketed and the others of an exportation kind. The samples were prepared by infusion with deionized water. To carry out the calibration, standard solutions were prepared with different concentrations of Al, Si, K, Ca, Ti, Cr, Fe, Ni, Zn and Se. The measurements were carried out using a white beam of synchrotron radiation for excitation and a Si (Li) semiconductor detector for detection. By employing Synchrotron Radiation Total Reflection X-Ray Fluorescence Analysis (SR-TXRF) it was possible to evaluate the concentrations of P, S, Cl, K, Ca, Mn, Fe, Cu, Zn, Rb and Ba. The detection limits for 300 s counting time were in the range of 0.03 (Ca) to 30 ng.g{sup -1} (Rb), respectively. (author)

  5. Metals determination in wood treated by synchrotron radiation X-ray fluorescence analysis

    Vives, Ana Elisa Sirito de [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo]. E-mail: aesvives@unimep.br; Silva, Richard Maximiliano da Cunha [Centro de Energia Nuclear na Agricultura, Piracicaba, SP (Brazil)]. E-mail: maxcunha@cena.usp.br; Medeiros, Jean Gabriel da Silva; Tomazello Filho, Mario [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz]. E-mail: jeangm@esalq.usp.br; mtomazel@esalq.usp.br; Moreira, Silvana [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo]. E-mail: Silvana@fec.unicamp.br; Zucchi, Orgheda Luiza Araujo Domingues [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: olzucchi@fcfrp.usp.br; Barroso, Regina Cely [Universidade do Estado, Rio de Janeiro, RJ (Brazil)]. E-mail: cely@uerj.br

    2005-07-01

    The paper describes the use of X-Ray fluorescence analysis for distribution and quantification of metals in the hardwood (Eucalyptus sp) and softwood (Pinus sp) treated with CCA (copper-chromium-arsenic). The sapwood/heartwood for hardwood sample and the growth-rings for softwood sample were analyzed. The samples were scanned in 320 mm steps in the vertical direction. For excitation of the elements a white beam synchrotron radiation of {approx} 320 x 180 mm was employed and for the X-ray detection a Si(Li) semiconductor detector. The elements K, Ca, Cr, Mn, Cu, Zn and As were determined. Fundamental parameters were used to quantify the elements concentrations. (author)

  6. Analysis of primary aromatic amines using precolumn derivatization by HPLC fluorescence detection and online MS identification.

    Zhao, Xianen; Suo, Yourui

    2008-03-01

    2-(2-phenyl-1H-phenanthro-[9,10-d]imidazole-1-yl)-acetic acid (PPIA) and 2-(9-acridone)-acetic acid (AAA), two novel precolumn fluorescent derivatization reagents, have been developed and compared for analysis of primary aromatic amines by high performance liquid chromatographic fluorescence detection coupled with online mass spectrometric identification. PPIA and AAA react rapidly and smoothly with the aromatic amines on the basis of a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) as dehydrating catalyst to form stable derivatives with emission wavelengths at 380 and 440 nm, respectively. Taking six primary aromatic amines (aniline, 2-methylaniline, 2-methoxyaniline, 4-methylaniline, 4-chloroaniline, and 4-bromoaniline) as testing compounds, derivatization conditions such as coupling reagent, basic catalyst, reaction temperature and time, reaction solvent, and fluorescent labeling reagent concentration have also been investigated. With the better PPIA method, chromatographic separation of derivatized aromatic amines exhibited a good baseline resolution on an RP column. At the same time, by online mass spectrometric identification with atmospheric pressure chemical ionization (APCI) source in positive ion mode, the PPIA-labeled derivatives were characterized by easy-to-interpret mass spectra due to the prominent protonated molecular ion m/z [M + H](+) and specific fragment ions (MS/MS) m/z 335 and 295. The linear range is 24.41 fmol-200.0 pmol with correlation coefficients in the range of 0.9996-0.9999, and detection limits of PPIA-labeled aromatic amines are 0.12-0.21 nmol/L (S/N = 3). Method repeatability, precision, and recovery were evaluated and the results were excellent for the efficient HPLC analysis. The most important argument, however, was the high sensitivity and ease-of-handling of the PPIA method. Preliminary experiments with wastewater samples collected from the waterspout of a paper mill and its nearby soil where

  7. Fluorescence In Situ Hybridization (FISH Signal Analysis Using Automated Generated Projection Images

    Xingwei Wang

    2012-01-01

    Full Text Available Fluorescence in situ hybridization (FISH tests provide promising molecular imaging biomarkers to more accurately and reliably detect and diagnose cancers and genetic disorders. Since current manual FISH signal analysis is low-efficient and inconsistent, which limits its clinical utility, developing automated FISH image scanning systems and computer-aided detection (CAD schemes has been attracting research interests. To acquire high-resolution FISH images in a multi-spectral scanning mode, a huge amount of image data with the stack of the multiple three-dimensional (3-D image slices is generated from a single specimen. Automated preprocessing these scanned images to eliminate the non-useful and redundant data is important to make the automated FISH tests acceptable in clinical applications. In this study, a dual-detector fluorescence image scanning system was applied to scan four specimen slides with FISH-probed chromosome X. A CAD scheme was developed to detect analyzable interphase cells and map the multiple imaging slices recorded FISH-probed signals into the 2-D projection images. CAD scheme was then applied to each projection image to detect analyzable interphase cells using an adaptive multiple-threshold algorithm, identify FISH-probed signals using a top-hat transform, and compute the ratios between the normal and abnormal cells. To assess CAD performance, the FISH-probed signals were also independently visually detected by an observer. The Kappa coefficients for agreement between CAD and observer ranged from 0.69 to 1.0 in detecting/counting FISH signal spots in four testing samples. The study demonstrated the feasibility of automated FISH signal analysis that applying a CAD scheme to the automated generated 2-D projection images.

  8. Complement: Alive and Kicking Nanomedicines

    Andersen, Alina Joukainen; Hashemi, S.H.; Andresen, Thomas Lars

    2009-01-01

    Administration of liposome- and polymer-based clinical nanomedicines, as well as many other proposed multifunctional nanoparticles, often triggers hypersensitivity reactions without the involvement of IgE. These anaphylactic reactions are believed to be secondary to activation of the complement...... their procoagulant activity, and has the capacity to elicit non-lytic stimulatory responses from vascular endothelial cells. Here we discuss the molecular basis of complement activation by liposomes, including poly(ethylene glycol) coated vesicles, and other related lipid-based and phospholipid-poly(ethylene glycol...

  9. Application of radionuclide sources for excitation in energy-dispersive X-ray fluorescence analysis

    Hoffmann, P.

    1986-01-01

    X-ray fluorescence (XRF) analysis is in broad application in many fields of science where elemental determinations are necessary. Solid and liquid samples are analyzed by this method. Solids are introduced in thin or thick samples as melted glass, pellets, powders or as original specimen. The excitation of X-ray spectra can be performed by specific and polychromic radiation of X-ray tubes, by protons, deuterons, α-particles, heavy ions and synchrotron radiation from accelerators and by α-particles, X- and γ-rays and by bremsstrahlung generated by β - -particles from radionuclide sources. The radionuclides are devided into groups with respect to their decay mode and the energy of the emitted radiation. The broad application of radionuclides in XRF excitation is shown in examples as semi-quantitative analysis of glasses, as quantitative analysis of coarse ceramics and as quantitative determination of heavy elements (mainly actinides) in solutions. The advantages and disadvantages of radionuclide excitation in XRF analysis are discussed. (orig.) [de

  10. Depth profile analysis of non-specific fluorescence and color of tooth tissues after peroxide bleaching.

    Klukowska, Malgorzata; Götz, Hermann; White, Donald J; Zoladz, James; Schwarz, Björn-Olaf; Duschner, Heinz

    2013-02-01

    To examine laboratory changes of endogenous non-specific fluorescence and color throughout subsurface of tooth structures prior to and following peroxide bleaching. Extracted human teeth were cross sectioned and mounted on glass slides. Cross sections were examined for internal color (digital camera) and nonspecific fluorescence (microRaman spectroscopy) throughout the tooth structure at specified locations. Surfaces of sections were then saturation bleached for 70 hours with a gel containing 6% hydrogen peroxide. Cross sections were reexamined for color and non-specific fluorescence changes. Unbleached enamel, dentin-enamel junction and dentin exhibit different CIELab color and non-specific fluorescence properties. Bleaching of teeth produced significant changes in color of internal cross sections and substantial reductions of non-specific fluorescence levels within enamel dentin and DEJ. Enamel and dentin non-specific fluorescence were reduced to common values with bleaching with enamel and the DEJ showing larger reductions than dentin.

  11. Analysis of fluorescence quenching of pyronin B and pyronin Y by molecular oxygen in aqueous solution

    Celebi, Neslihan [Faculty of Arts and Sciences, Department of Chemistry, Atatuerk University, 25240 Erzurum (Turkey); Arik, Mustafa [Faculty of Arts and Sciences, Department of Chemistry, Atatuerk University, 25240 Erzurum (Turkey); Onganer, Yavuz [Faculty of Arts and Sciences, Department of Chemistry, Atatuerk University, 25240 Erzurum (Turkey)]. E-mail: yonganer@atauni.edu.tr

    2007-09-15

    The fluorescence quenching of pyronin B and pyronin Y molecules by molecular oxygen in aqueous solution was studied by using steady-state and time-resolved fluorescence and UV-Vis absorption spectroscopy techniques. In order to understand the quenching mechanism, fluorescence decays, absorption and fluorescence spectra of the probes were recorded as a function of the oxygen concentration and temperature. The quenching was found to be appreciable and shows positive deviation in the Stern-Volmer representation obtained from the fluorescence intensity ratio. Fluorescence quenching constants (k {sub q}) were calculated from the {tau} {sub o}/{tau} vs. [Q] plots having linear correlation and compared with calculated diffusion-controlled rate constants (k {sub diff}) values. Experimental results were in good agreement with the simultaneous dynamic and static quenching model.

  12. Analysis of fluorescence quenching of pyronin B and pyronin Y by molecular oxygen in aqueous solution

    Celebi, Neslihan; Arik, Mustafa; Onganer, Yavuz

    2007-01-01

    The fluorescence quenching of pyronin B and pyronin Y molecules by molecular oxygen in aqueous solution was studied by using steady-state and time-resolved fluorescence and UV-Vis absorption spectroscopy techniques. In order to understand the quenching mechanism, fluorescence decays, absorption and fluorescence spectra of the probes were recorded as a function of the oxygen concentration and temperature. The quenching was found to be appreciable and shows positive deviation in the Stern-Volmer representation obtained from the fluorescence intensity ratio. Fluorescence quenching constants (k q ) were calculated from the τ o /τ vs. [Q] plots having linear correlation and compared with calculated diffusion-controlled rate constants (k diff ) values. Experimental results were in good agreement with the simultaneous dynamic and static quenching model

  13. Acute toxicity of excess mercury on the photosynthetic performance of cyanobacterium, S. platensis--assessment by chlorophyll fluorescence analysis.

    Lu, C M; Chau, C W; Zhang, J H

    2000-07-01

    Measurement of chlorophyll fluorescence has been shown to be a rapid, non-invasive, and reliable method to assess photosynthetic performance in a changing environment. In this study, acute toxicity of excess Hg on the photosynthetic performance of the cyanobacterium S. platensis, was investigated by use of chlorophyll fluorescence analysis after cells were exposed to excess Hg (up to 20 microM) for 2 h. The results determined from the fast fluorescence kinetics showed that Hg induced a significant increase in the proportion of the Q(B)-non-reducing PSII reaction centers. The fluorescence parameters measured under the steady state of photosynthesis demonstrated that the increase of Hg concentration led to a decrease in the maximal efficiency of PSII photochemistry, the efficiency of excitation energy capture by the open PSII reaction centers, and the quantum yield of PSII electron transport. Mercury also resulted in a decrease in the coefficients of photochemical and non-photochemical quenching. Mercury may have an acute toxicity on cyanobacteria by inhibiting the quantum yield of photosynthesis sensitively and rapidly. Such changes occurred before any other visible damages that may be evaluated by other conventional measurements. Our results also demonstrated that chlorophyll fluorescence analysis can be used as a useful physiological tool to assess early stages of change in photosynthetic performance of algae in response to heavy metal pollution.

  14. Structural analysis of human complement protein H: homology with C4b binding protein, beta 2-glycoprotein I, and the Ba fragment of B2

    Kristensen, Torsten; Wetsel, R A; Tack, B F

    1986-01-01

    We report here a partial primary structure for human complement protein H. Tryptic peptides comprising 27% of the H molecule were isolated by conventional techniques and were sequenced (333 amino acid residues). Several mixed-sequence oligonucleotide probes were constructed, based on the peptide...... sequence data, and were used to screen a human liver cDNA library. The largest recombinant plasmid (pH1050), which hybridized with two probes, was further characterized. The cDNA insert of this plasmid contained coding sequence (672 bp) for 224 amino acids of H. The 3' end of this clone had...... a polyadenylated tail preceded by a polyadenylation recognition site (ATTAAA) and a 3'-untranslated region (229 bp). Four regions of internal homology, each about 60 amino acids in length, were observed in the derived protein sequence from this cDNA clone, and a further seven from the tryptic peptide sequences...

  15. Three-dimensional fluorescence analysis of chernozem humic acids and their electrophoretic fractions

    Trubetskoi, O. A.; Trubetskaya, O. E.

    2017-09-01

    Polyacrylamide gel electrophoresis in combination with size-exclusion chromatography (SEC-PAGE) has been used to obtain stable electrophoretic fractions of different molecular size (MS) from chernozem humic acids (HAs). Three-dimensional fluorescence charts of chernozem HAs and their fractions have been obtained for the first time, and all fluorescence excitation-emission maxima have been identified in the excitation wavelength range of 250-500 nm. It has been found that fractionation by the SEC-PAGE method results in a nonuniform distribution of protein- and humin-like fluorescence of the original HA preparation among the electrophoretic fractions. The electrophoretic fractions of the highest and medium MSs have only the main protein-like fluorescence maximum and traces of humin-like fluorescence. In the electrophoretic fraction of the lowest MS, the intensity of protein-like fluorescence is low, but the major part of humin-like fluorescence is localized there. Relationships between the intensity of protein-like fluorescence and the weight distribution of amino acids have been revealed, as well as between the degree of aromaticity and the intensity of humin-like fluorescence in electrophoretic fractions of different MSs. The obtained relationships can be useful in the interpretation of the spatial structural organization and ecological functions of soil HAs.

  16. Fluorescent analysis of interaction of flavonols with hemoglobin and bovine serum albumin

    Sentchouk, V. V.; Bondaryuk, E. V.

    2007-09-01

    We have studied the fluorescent properties of flavonols (quercetin, fisetin, morin, rutin) with the aim of studying possible interaction with hemoglobin and bovine serum albumin (BSA). We observed an increase in the intensity of intrinsic fluorescence for all the flavonols except rutin in the presence of BSA. From the changes in the fluorescence spectra, we concluded that tautomeric forms are formed on interaction with hemoglobin. We determined the interconnection between the structure of related flavonols and their fluorescent properties on interaction with proteins, and we determined the binding constants for binding with BSA and hemoglobin.

  17. Automated parasite faecal egg counting using fluorescence labelling, smartphone image capture and computational image analysis.

    Slusarewicz, Paul; Pagano, Stefanie; Mills, Christopher; Popa, Gabriel; Chow, K Martin; Mendenhall, Michael; Rodgers, David W; Nielsen, Martin K

    2016-07-01

    Intestinal parasites are a concern in veterinary medicine worldwide and for human health in the developing world. Infections are identified by microscopic visualisation of parasite eggs in faeces, which is time-consuming, requires technical expertise and is impractical for use on-site. For these reasons, recommendations for parasite surveillance are not widely adopted and parasite control is based on administration of rote prophylactic treatments with anthelmintic drugs. This approach is known to promote anthelmintic resistance, so there is a pronounced need for a convenient egg counting assay to promote good clinical practice. Using a fluorescent chitin-binding protein, we show that this structural carbohydrate is present and accessible in shells of ova of strongyle, ascarid, trichurid and coccidian parasites. Furthermore, we show that a cellular smartphone can be used as an inexpensive device to image fluorescent eggs and, by harnessing the computational power of the phone, to perform image analysis to count the eggs. Strongyle egg counts generated by the smartphone system had a significant linear correlation with manual McMaster counts (R(2)=0.98), but with a significantly lower coefficient of variation (P=0.0177). Furthermore, the system was capable of differentiating equine strongyle and ascarid eggs similar to the McMaster method, but with significantly lower coefficients of variation (P<0.0001). This demonstrates the feasibility of a simple, automated on-site test to detect and/or enumerate parasite eggs in mammalian faeces without the need for a laboratory microscope, and highlights the potential of smartphones as relatively sophisticated, inexpensive and portable medical diagnostic devices. Copyright © 2016 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

  18. Portable x-ray fluorescence for the analysis of chromium in nail and nail clippings

    Fleming, David E.B.; Ware, Chris S.

    2017-01-01

    Assessment of chromium content in human nail or nail clippings could serve as an effective biomarker of chromium status. The feasibility of a new portable x-ray fluorescence (XRF) approach to chromium measurement was investigated through analysis of nail and nail clipping phantoms. Five measurements of 180 s (real time) duration were first performed on six whole nail phantoms having chromium concentrations of 0, 2, 5, 10, 15, and 20 µg/g. Using nail clippers, these phantoms were then converted to nail clippings, and assembled into different mass groups of 20, 40, 60, 80, and 100 mg for additional measurements. The amplitude of the chromium Kα characteristic x-ray energy peak was examined as a function of phantom concentration for all measurement conditions to create a series of calibration lines. The minimum detection limit (MDL) for chromium was also calculated for each case. The chromium MDL determined from the whole nail intact phantoms was 0.88±0.03 µg/g. For the clipping phantoms, the MDL ranged from 1.2 to 3.3 µg/g, depending on the mass group analyzed. For the 40 mg clipping group, the MDL was 1.2±0.1 µg/g, and higher mass collections did not improve upon this result. This MDL is comparable to chromium concentration levels seen in various studies involving human nail clippings. Further improvements to the portable XRF technique would be required to detect chromium levels expected from the lower end of a typical population. - Highlights: • Portable x-ray fluorescence (XRF) was explored as a technique to assess levels of chromium in human nails or nail clippings. • Results were found to depend on the mass of clipping sample provided. • Minimum detection limits for chromium were similar to concentration levels found in previous studies of human nail clippings.

  19. X-ray fluorescence analysis of low concentrations metals in geological samples and technological products

    Lagoida, I. A.; Trushin, A. V.

    2016-02-01

    For the past several years many nuclear physics methods of quantitative elemental analysis have been designed. Many of these methods have applied in different devices which have become useful and effective instrument in many industrial laboratories. Methods of a matter structure analysis are based on the intensity detection of the X-ray radiation from the nuclei of elements which are excited by external X-ray source. The production of characteristic X-rays involves transitions of the orbital electrons of atoms in the target material between allowed orbits, or energy states, associated with ionization of the inner atomic shells. One of these methods is X-ray fluorescence analysis, which is widespread in metallurgical and processing industries and is used to identify and measure the concentration of the elements in ores and minerals on a conveyor belt. Samples of copper ore with known concentrations of elements, were taken from the Ural deposit. To excite the characteristic X-rays radionuclide sources 109Cd, with half-life 461.4 days were used. After finding the calibration coefficients, control measurements of samples and averaging of overall samples were made. The measurement error did not exceed 3%.

  20. Multilayers quantitative X-ray fluorescence analysis applied to easel paintings.

    de Viguerie, Laurence; Sole, V Armando; Walter, Philippe

    2009-12-01

    X-ray fluorescence spectrometry (XRF) allows a rapid and simple determination of the elemental composition of a material. As a non-destructive tool, it has been extensively used for analysis in art and archaeology since the early 1970s. Whereas it is commonly used for qualitative analysis, recent efforts have been made to develop quantitative treatment even with portable systems. However, the interpretation of the results obtained with this technique can turn out to be problematic in the case of layered structures such as easel paintings. The use of differential X-ray attenuation enables modelling of the various layers: indeed, the absorption of X-rays through different layers will result in modification of intensity ratio between the different characteristic lines. This work focuses on the possibility to use XRF with the fundamental parameters method to reconstruct the composition and thickness of the layers. This method was tested on several multilayers standards and gives a maximum error of 15% for thicknesses and errors of 10% for concentrations. On a painting test sample that was rather inhomogeneous, the XRF analysis provides an average value. This method was applied in situ to estimate the thickness of the layers a painting from Marco d'Oggiono, pupil of Leonardo da Vinci.

  1. Fluorescence, electrophoretic and chromatographic fingerprints of herbal medicines and their comparative chemometric analysis.

    Mazina, Jekaterina; Vaher, Merike; Kuhtinskaja, Maria; Poryvkina, Larisa; Kaljurand, Mihkel

    2015-07-01

    The aim of the present study was to compare the polyphenolic compositions of 47 medicinal herbs (HM) and four herbal tea mixtures from Central Estonia by rapid, reliable and sensitive Spectral Fluorescence Signature (SFS) method in a front face mode. The SFS method was validated for the main identified HM representatives including detection limits (0.037mgL(-1) for catechin, 0.052mgL(-1) for protocatechuic acid, 0.136mgL(-1) for chlorogenic acid, 0.058mgL(-1) for syringic acid and 0.256mgL(-1) for ferulic acid), linearity (up to 5.0-15mgL(-1)), intra-day precision (RSDs=6.6-10.6%), inter-day precision (RSDs=6.4-13.8%), matrix effect (-15.8 to +5.5) and recovery (85-107%). The phytochemical fingerprints were differentiated by parallel factor analysis (PARAFAC) combined with hierarchical cluster analysis (CA) and principal component analysis (PCA). HM were clustered into four main clusters (catechin-like, hydroxycinnamic acid-like, dihydrobenzoic acid-like derivatives containing HM and HM with low/very low content of fluorescent constituents) and 14 subclusters (rich, medium, low/very low contents). The average accuracy and precision of CA for validation HM set were 97.4% (within 85.2-100%) and 89.6%, (within 66.7-100%), respectively. PARAFAC-PCA/CA has improved the analysis of HM by the SFS method. The results were verified by two separation methods CE-DAD and HPLC-DAD-MS also combined with PARAFAC-PCA/CA. The SFS-PARAFAC-PCA/CA method has potential as a rapid and reliable tool for investigating the fingerprints and predicting the composition of HM or evaluating the quality and authenticity of different standardised formulas. Moreover, SFS-PARAFAC-PCA/CA can be implemented as a laboratory and/or an onsite method. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Wavelength Dispersive X-ray Fluorescence Spectrometry for the Analysis of Organic Polymer Film

    Choi, Yong Suk; Park, Yong Joon; Kim, Jong Yun

    2008-01-01

    Recently, many studies have been focused on the thin films because there are numerous industrial processes relevant to thin films such as fuel cells, sensors, lubricants, coatings, and so on. Physical and chemical properties of solid surface have been modified by ultra-thin coatings such as Langmuir-Blodgett (LB) method with a variety of types of organic functional materials for the specific purposes in many applications. In addition, the layer-by-layer technique using polyelectrolyte films are now of interest as biosensors, electrochromic and electroluminescent devices, etc. In general, several methods such as X-ray or neutron reflectivity, and quartz crystal microbalance (QCM) have been utilized for the thin film analysis. These optical techniques can measure the film thicknesses up to hundreds of nanometers while X-ray photoelectron spectroscopy is widely used to study a few nanometers thick films. Other methods such as X-ray Photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atom force microscopy (AFM) have also been used in the film analysis in spite of some disadvantages for each method. X-ray fluorescence (XRF) has long been used as a rapid and simple analytical tool for the analysis of elemental composition of materials. XRF technique is suitable for on-line or in-line real-time monitoring because it is a non-destructive and rapid analysis with good precision and good accuracy at low cost. The aim of this work is to develop a new analytical technique for the quantitative analysis of polymer film on metal substrate. In the present study, Compton peak profile was investigated under different experimental conditions by using wavelength-dispersive XRF (WD-XRF). Compared to energy-dispersive XRF (ED-XRF), WD-XRF is more adequate in an accurate quantitative analysis of thin organic film

  3. Comparative analysis of monoclonal antibody N-glycosylation using stable isotope labelling and UPLC-fluorescence-MS.

    Millán Martín, Silvia; Delporte, Cédric; Farrell, Amy; Navas Iglesias, Natalia; McLoughlin, Niaobh; Bones, Jonathan

    2015-03-07

    A twoplex method using (12)C6 and (13)C6 stable isotope analogues (Δmass = 6 Da) of 2-aminobenzoic acid (2-AA) is described for quantitative analysis of N-glycans present on monoclonal antibodies and other glycoproteins using ultra performance liquid chromatography with sequential fluorescence and accurate mass tandem quadrupole time of flight (QToF) mass spectrometric detection.

  4. Moessbauer spectroscopy and X-ray fluorescence analysis in studies for determinate the sources of several prehispanic objects

    Arriola S, H.; Ramos R, P.; Castro V, P.; Jimenez R, A.; Flores D, F.; Garcia Moreno C, C.

    1980-01-01

    A study by the Moessbauer effect and X-ray fluorescence analysis of the mexican prehispanic ceramic specimens is presented. Several iron compounds of the ceramics are determined, the different iron compounds indicate different sources of the clays, and different forms of ovens used with them, this compounds are identified by the differents oxidation states of the magnetic iron Fe 3+ , Fe 2+ . (author)

  5. The use of rapid quantitative x-ray fluorescence analysis in paper manufacturing and construction materials industry

    Kocman, V.; Foley, L.; Woodger, S.C.

    1985-01-01

    A modern analytical laboratory of a large corporation manufacturing paper, construction materials and chemicals must be sufficiently diversified in methodology to provide accurate results in the shortest possible time. Among other techniques the implementation of an automated ''menu'' driven wavelength dispersive spectrometer allowed for the setting-up of a variety of quantitative X-ray fluorescence methods. An overview of these methods is given as presented at the 33rd. Annual Conference on the Application of X-ray Fluorescence Analysis in Denver, Colorado, 1984

  6. Results of improvement of simultaneous and sequential x-ray fluorescence equipment for quantitative routine analysis

    Zsamboky, Jozsef

    1985-01-01

    Two main types of x-ray fluorescence analyzers measuring sequentially and simultaneously, respectively, the intensities at given wave lengths are described. The main parts of an up to date x-ray fluorescence analyzer are surveyed in detail. The advantages and disadvantages of both methods are discussed. Some results on calibration and optimization are given. (D.Gy.)

  7. Preparation and application of new fluorescein-labeled fumonisins B1 in fluorescence polarization analysis technique

    Objective: To prepare a new fluorescent tracer against common mycotoxins such as fumonisin B1 in order to replace 6-(4,6-Dichlorotriazinyl) aminofluorescein (6-DTAF), an expensive marker, and to develop a technique for quick detection of fumonisin B1 based on the principle of fluorescence polarizati...

  8. Threshold analysis and biodistribution of fluorescently labeled bevacizumab in human breast cancer

    Koch, Maximillian; de Jong, Johannes S; Glatz, Jürgen; Symvoulidis, Panagiotis; Lamberts, Laetitia E; Adams, Arthur; Kranendonk, Mariëtte E G; Terwisscha van Scheltinga, Anton G T; Aichler, Michaela; Jansen, Liesbeth; de Vries, Jakob; Lub-de Hooge, Marjolijn N; Schröder, Carolina P; Jorritsma-Smit, Annelies; Linssen, Matthijs D; de Boer, Esther; van der Vegt, Bert; Nagengast, Wouter B; Elias, Sjoerd G; Oliveira, Sabrina; Witkamp, Arjen; Mali, Willem P Th M; van der Wall, Elsken; Garcia-Allende, Beatriz P; Van Diest, Paul J; de Vries, Elisabeth G; Walch, Axel; van Dam, Gooitzen M; Ntziachristos, Vasilis

    2017-01-01

    In vivo tumor labeling with fluorescent agents may assist endoscopic and surgical guidance for cancer therapy as well as create opportunities to directly observe cancer biology in patients. However, malignant and non-malignant tissues are usually distinguished on fluorescence images by applying

  9. Threshold analysis and biodistribution of fluorescently labeled bevacizumab in human breast cancer

    Koch, Maximillian; de Jong, Johannes S; Glatz, Jürgen; Symvoulidis, Panagiotis; Lamberts, Laetitia E; Adams, Arthur; Kranendonk, Mariëtte E G; Terwisscha van Scheltinga, Anton G T; Aichler, Michaela; Jansen, Liesbeth; de Vries, Jakob; Lub-de Hooge, Marjolijn N; Schröder, Carolina P; Jorritsma-Smit, Annelies; Linssen, Matthijs D; de Boer, Esther; van der Vegt, Bert; Nagengast, Wouter B; Elias, Sjoerd G; Oliveira, Sabrina|info:eu-repo/dai/nl/304841455; Witkamp, Arjen; Mali, Willem P Th M; van der Wall, Elsken; Garcia-Allende, Beatriz P; Van Diest, Paul J; de Vries, Elisabeth G; Walch, Axel; van Dam, Gooitzen M; Ntziachristos, Vasilis

    2016-01-01

    In vivo tumor labeling with fluorescent agents may assist endoscopic and surgical guidance for cancer therapy as well as create opportunities to directly observe cancer biology in patients. However, malignant and non-malignant tissues are usually distinguished on fluorescence images by applying

  10. Microspectroscopic analysis of green fluorescent proteins infiltrated into mesoporous silica nanochannels

    Ma, Yujie; Rajendran, Prayanka; Blum, Christian; Cesa, Yanina; Gartmann, Nando; Brühwiler, Dominik; Subramaniam, Vinod

    2011-01-01

    The infiltration of enhanced green fluorescent protein (EGFP) into nanochannels of different diameters in mesoporous silica particles was studied in detail by fluorescence microspectroscopy at room temperature. Silica particles from the MCM-41, ASNCs and SBA-15 families possessing nanometer-sized

  11. Ultratrace analysis of actinides via coprecipitation/laser-induced fluorescence spectroscopy

    Miller, S.M.

    1982-01-01

    Actinides were selectively preconcentrated by coprecipitating each out of solution with a fluoride matrix and calcining each sample at 800 0 C. The fluorescence spectrum of each sample was recorded by illuminating the sample with laser light and detecting fluorescence with either a fluorescence/Raman spectrometer, an infrared spectrometer or in certain cases a filter fluorimeter. Three previously unobserved actinide spectra were recorded. Narrow lines at 546.9 nm, 564.6 nm, and 569.6 nm were found for CaF 2 :PuO 2++ at 10K. CaF 2 :Am + 3 displayed two broadband fluorescent peaks at 625 nm and 746 nm at room temperature and CaF 2 :Pu + 3 possessed a fluorescent peak at 1.22 microns at 10K. Energy transfer was observed in the form of Tb fluorescence quenching in TbF 3 :Pu + 3 when Pu was present in quantities of 10 ppM or more and in the form of Tb fluorescence enhancement in TbF 3 :Am + 3 when 1 ppM or more of Am was present. Careful sample preparation and the use of temporal as well as a spectral discrimination system extended the detection limit of U from 1 ml samples to the subfemtogram level. The fluorescence detection limits for Pu and Am were extended to 0.48 and 0.032 pg/ml. 39 figures, 9 tables

  12. Project Title: Radiochemical Analysis by High Sensitivity Dual-Optic Micro X-ray Fluorescence

    Havrilla, George J.; Gao, Ning

    2002-01-01

    A novel dual-optic micro X-ray fluorescence instrument will be developed to do radiochemical analysis of high-level radioactive wastes at DOE sites such as Savannah River Site and Hanford. This concept incorporates new X-ray optical elements such as monolithic polycapillaries and double bent crystals, which focus X-rays. The polycapillary optic can be used to focus X-rays emitted by the X-ray tube thereby increasing the X-ray flux on the sample over 1000 times. Polycapillaries will also be used to collect the X-rays from the excitation site and screen the radiation background from the radioactive species in the specimen. This dual-optic approach significantly reduces the background and increases the analyte signal thereby increasing the sensitivity of the analysis. A doubly bent crystal used as the focusing optic produces focused monochromatic X-ray excitation, which eliminates the bremsstrahlung background from the X-ray source. The coupling of the doubly bent crystal for monochromatic excitation with a polycapillary for signal collection can effectively eliminate the noise background and radiation background from the specimen. The integration of these X-ray optics increases the signal-to-noise and thereby increases the sensitivity of the analysis for low-level analytes. This work will address a key need for radiochemical analysis of high-level waste using a non-destructive, multi-element, and rapid method in a radiation environment. There is significant potential that this instrumentation could be capable of on-line analysis for process waste stream characterization at DOE sites

  13. Increasing of sensitivity of fluorescent immunoassay analysis of alpha-fetoprotein by means of plasmonical silver nanoparticles

    Vashchenko, S.V.; Min'ko, A.A.; Romanenko, A.A.; Gaponenko, S.V.; Kulakovich, O.S.

    2014-01-01

    A test system is proposed based on metal enhanced fluorescence to analyze low concentrations of alpha-fetoprotein (AFP), a tumor marker. Antigen-antibody reaction was performed on polystyrene plates coated with silver nanoparticles to increase sensitivity of fluorescent immunoassay and signal-to-noise ratio as compared to silver-free system. As compared to widely used ELISA technique and other immunoassay techniques the proposed approach is characterized by smaller probe volume, fast analysis and simplicity. The proposed test system uses layer-by-layer assembly approach, LED excitation and nanowatt photodetection set-up. The proposed test system offers AFP detection at concentrations used in clinical practice. Fluorescence enhancement for labeled AFP antibodies on a silver substrate was found to depend on antibodies concentration and was up to 6 times. (authors)

  14. Lie Group Analysis of the Photo-Induced Fluorescence of Drosophila Oogenesis with the Asymmetrically Localized Gurken Protein.

    Jen-Cheng Wang

    Full Text Available Lie group analysis of the photo-induced fluorescence of Drosophila oogenesis with the asymmetrically localized Gurken protein has been performed systematically to assess the roles of ligand-receptor complexes in follicle cells. The (2×2 matrix representations resulting from the polarized tissue spectra were employed to characterize the asymmetrical Gurken distributions. It was found that the fluorescence of the wild-type egg shows the Lie point symmetry X 23 at early stages of oogenesis. However, due to the morphogen regulation by intracellular proteins and extracellular proteins, the fluorescence of the embryogenesis with asymmetrically localized Gurken expansions exhibits specific symmetry features: Lie point symmetry Z 1 and Lie point symmetry X 1. The novel approach developed herein was successfully used to validate that the invariant-theoretical characterizations are consonant with the observed asymmetric fluctuations during early embryological development.

  15. Specific solvent effect on lumazine photophysics: A combined fluorescence and intrinsic reaction coordinate analysis

    Moyon, N. Shaemningwar; Gashnga, Pynsakhiat Miki; Phukan, Smritakshi; Mitra, Sivaprasad, E-mail: smitra@nehu.ac.in

    2013-06-27

    Highlights: • Correlation of lumazine photophysics with multiparametric Kamlet–Taft equation. • Solvent basicity (β) contributes maximum towards the hydrogen bonding (HB) effect. • HB interaction occurs at N1 and N3 proton in S{sub 0} and S{sub 1} state, respectively. • IRC calculation for different tautomerization processes both in S{sub 0} and S{sub 1} states. • Process related to riboflavin biosynthesis is thermodynamically feasible. - Abstract: The photophysical properties and tautomerization behavior of neutral lumazine were studied by fluorescence spectroscopy and density functional theory calculation. A quantitative estimation of the contributions from different solvatochromic parameters, like solvent polarizibility (π{sup ∗}), hydrogen bond donation (α) and hydrogen bond accepting (β) ability of the solvent, was made using linear free energy relationships based on the Kamlet–Taft equation. The analysis reveals that the hydrogen bond acceptance ability of the solvent is the most important parameter characterizing the excited state behavior of lumazine. Theoretical calculations result predict an extensive charge redistribution of lumazine upon excitation corresponding to the N3 and N1 proton dissociation sites by solvents in the ground and excited states, respectively. Comparison of S{sub 0} and S{sub 1} state potential energy curves constructed for several water mediated tautomerization processes by intrinsic reaction coordinate analysis of lumazine-H{sub 2}O cluster shows that (3,2) and (1,8) hydrogen migrations are the most favorable processes upon excitation.

  16. Multi-elemental analysis of marine sediments of Manila Bay using x-ray fluorescence spectrometry

    Rosales, Colleen Marciel Fontelera

    2011-04-01

    An analysis of the marine sediments of Manila Bay was done by employing X-ray fluorescence spectrometry. The general trends observed in sediments are increasing (Ca and Sr), decreasing (Zr), or constant (Cl, Na, S, K) with respect to depth, sometimes, no trend can be observed. These trends are further explained by correlations present among these elements, plus all the other elements. The two X RF data analysis methods Auto Quantify and AXIL were also compared on the basis of the correlation plot obtained. AutoQuantify gave clearer correlations; thus, results from this method were used for constructing correlation plots. Correlations using Microsoft Excel and Stat graphics Centurion X V show that there are naturally occurring [lithogenic (Si, Ti, Al, Mg, Rb, Zn and Fe), biogenic (Ca, Mg), and conservative (Na, Cl)] and non-naturally occurring [mostly anthropogenic, brought to the bodies of water by aeolian or fluvial input (heavy metals Pb-Cu-Zn and Ni-Cr)] correlation present in the sediments. Moreover, pairs of elements that may coexist in a source and not coexist in another (Cr and Mg, Cr and Ni) have also been observed. The heavy metal enrichment was attributed to the burning of fossil fuels, iron and steel manufacturing (present in Valenzuela-Bulacan area), ferry and fishing services and other industrialization activities present in Manila Bay. Marine organisms are affected by the presence of these heavy metals by means of bioaccumulations, and may later on affect humans because of trophic transfer and bio magnification. (author)

  17. Chemical analysis of zinc electroplating solutions by x-ray fluorescence spectrometry

    Jung, Sung-Mo; Cho, Young-Mo; Na, Han-Gil

    2007-01-01

    A quantitative analysis method used to analyze chlorine, iron and zinc in electroplating solutions, using X-ray spectrometry in atmospheric He mode, is proposed. The present research concerns the replacement of the conventional analyses of electroplating solutions with rapid and reproducible quantification using X-ray fluorescence spectrometer. An in-depth investigation conducted in the present study identifies the species present in the real electroplating solutions. XRD patterns and semi-quantitative results for the electroplating solutions show synthetic standards based on the compositional range of solutions by analyzing the electroplating solutions obtained in real processes. 28 calibration standard solutions are prepared by diluting liquid standard solutions certified by titration and ICP-OES analyses used to construct the XRF calibration curves for Cl, Fe and Zn. The suggested method showed satisfactory precision and accuracy in the analysis of electroplating solutions. The present study provides evidences that the proposed XRF spectrometry could be an alternative analytical method to replace the conventional techniques by comparing the uncertainties estimated for each method. (author)

  18. Quality in the chemical analysis of biological matrices by fluorescence X-ray by energy dispersive

    Sousa, Evely E. de; Paiva, Jose Daniel S. de; Franca, Elvis J. de; Almeida, Macio E.S.; Cantinha, Rebeca S.; Hazin, Clovis A.

    2013-01-01

    The aim of this study was to obtain multielement analytical curves of high analytical rigor to the analysis of biological matrices by the technique of fluorescence x-ray energy dispersive - EDXRF. Calibration curves were constructed from the reference materials IAEA 140, IAEA 155, IAEA V8, V10 to the International Atomic Energy Agency - IAEA, and SRM1515, SRM 1547, SRM 1570a, SRM 1573a, SEM 1567a, to the National Institute of Standards and Technology - NIST. After energy calibration, all samples were subjected to vacuum to the analyzes by 100 seconds for each group of chemical elements. The voltages used were respectively 15 keV for chemical elements with less than atomic number 22 and 50 keV for the others. After the construction of the curves, the analytical quality was assessed by the analysis of a portion-test of the reference material SRM 2976, also produced by NIST. Based on the number of certified reference materials used for construction of calibration curves in this work, quality analytical protocol was originated with considerable reliability for quantification of chemical elements in biological samples by EDXR

  19. Effect of the sample matrix on measurement uncertainty in X-ray fluorescence analysis

    Morgenstern, P.; Brueggemann, L.; Wennrich, R.

    2005-01-01

    The estimation of measurement uncertainty, with reference to univariate calibration functions, is discussed in detail in the Eurachem Guide 'Quantifying Uncertainty in Analytical Measurement'. The adoption of these recommendations to quantitative X-ray fluorescence analysis (XRF) involves basic problems which are above all due to the strong influence of the sample matrix on the analytical response. In XRF-analysis, the proposed recommendations are consequently applicable only to the matrix corrected response. The application is also restricted with regard to both the matrices and analyte concentrations. In this context the present studies are aimed at the problems to predict measurement uncertainty also with reference to more variable sample compositions. The corresponding investigations are focused on the use of the intensity of the Compton scattered tube line as an internal standard to assess the effect of the individual sample matrix on the analytical response relatively to a reference matrix. Based on this concept the estimation of the measurement uncertainty of an analyte presented in an unknown specimen can be predicted in consideration of the data obtained under defined matrix conditions

  20. Quantitative X-ray fluorescence analysis at the ESRF ID18F microprobe

    Vekemans, B.; Vincze, L.; Somogyi, A.; Drakopoulos, M.; Kempenaers, L.; Simionovici, A.; Adams, F.

    2003-01-01

    The new ID18F end-station at the European synchrotron radiation facility (ESRF) in Grenoble (France) is dedicated to sensitive and accurate quantitative micro-X-ray fluorescence (XRF) analysis at the ppm level with accuracy better than 10% for elements with atomic numbers above 18. For accurate quantitative analysis, given a high level of instrumental stability, major steps are the extraction and conversion of experimental X-ray line intensities into elemental concentrations. For this purpose a two-step quantification approach was adopted. In the first step, the collected XRF spectra are deconvoluted on the basis of a non-linear least-squares fitting algorithm (AXIL). The extracted characteristic line intensities are then used as input for a detailed Monte Carlo (MC) simulation code dedicated to XRF spectroscopy taking into account specific experimental conditions (excitation/detection) as well as sample characteristics (absorption and enhancement effects, sample topology, heterogeneity etc.). The iterative use of the MC code gives a 'no-compromise' solution for the quantification problem

  1. Quantitative X-ray fluorescence analysis at the ESRF ID18F microprobe

    Vekemans, B. E-mail: vekemans@uia.ua.ac.be; Vincze, L.; Somogyi, A.; Drakopoulos, M.; Kempenaers, L.; Simionovici, A.; Adams, F

    2003-01-01

    The new ID18F end-station at the European synchrotron radiation facility (ESRF) in Grenoble (France) is dedicated to sensitive and accurate quantitative micro-X-ray fluorescence (XRF) analysis at the ppm level with accuracy better than 10% for elements with atomic numbers above 18. For accurate quantitative analysis, given a high level of instrumental stability, major steps are the extraction and conversion of experimental X-ray line intensities into elemental concentrations. For this purpose a two-step quantification approach was adopted. In the first step, the collected XRF spectra are deconvoluted on the basis of a non-linear least-squares fitting algorithm (AXIL). The extracted characteristic line intensities are then used as input for a detailed Monte Carlo (MC) simulation code dedicated to XRF spectroscopy taking into account specific experimental conditions (excitation/detection) as well as sample characteristics (absorption and enhancement effects, sample topology, heterogeneity etc.). The iterative use of the MC code gives a 'no-compromise' solution for the quantification problem.

  2. Elementary analysis of Alternanthera Maritima and Blutaparon Portulacoides (Gomphreneae, Amaranthacear) by X-ray fluorescence

    Salvador, M.J.; Dias, D.A.; Zucchi, O.L.A.D.; Nascimento Filho, V.F.

    2002-01-01

    The phytochemical study and the evaluation of biological activities of plants species have been intensified in the last years. The modernization of analytical equipment allowed significant progress in the natural products chemistry. Most of the plants researches emphasize the isolation of secondary metabolites and the metal analysis is neglected. In this study, aqueous and ethanolic extracts and the intact plant of Alternanthera maritima (aerial parts and roots) and Blutaparon portulacoides (aerial parts and roots), species commonly found on the beaches of eastern coast of Brazil (Restinga de Marica, RJ), were selected for analysis by energy dispersive X-ray fluorescence (EDXRF). With the standard sample aid, the correlation between the elementary sensitivity and the atomic numbers of the elements was determined. The elements P, K, Ca, Ti, Fe, Ni, As, Zn, Br, Sr, Sn and Sb, supported in membranes, were detected in the two analyzed plants, but only the elements in the interval 26 (Fe) ≤ Z ≤ 30 (Zn) were quantified with elementary concentration between 8,7 and 895,0 μg.g -1 . (author)

  3. Analysis of ancient masterly pieces of work by means of X-ray fluorescence analysis by dispersion in the energy

    Cesareo, R.; Cappio B, C.; Brunetti, A.; Rosales, M.A.; Castellano, A.; Gigante, G.E.; Fiorini, C.

    2004-01-01

    Energy dispersive X-ray fluorescence (EDXRF) analysis has been widely used for the analysis of works of art because it is non-destructive, multi-elemental, simple to utilize, and relatively inexpensive. In the last few years, miniaturized and portable X-ray tubes and high-resolution semiconductor detectors have been developed. This progress allowed the design and construction of portable equipments that can be easily transported all over the world, for use in museums, excavations, etc. In this work, these portable systems will be described and their usefulness demonstrated in the analysis of objects of archaeological value. First, we present the analysis of a lot of gold prehispanic jewels from the Museo del Templo Mayor in Mexico City; in the second place we present the results of analysis of the golden altar of St. Ambrogio in Milan, which is considered one of the most important goldsmith's works ever realized and the gold pigments from the fresco 'The chapel of the Scrovegni' by Giotto. In the third place we give a brief account of Mycenaean and pre-Mycenaean gold objects from the Museum Benaki in Athens. Finally, the results of bulk nuragic copper based ingots from the nuragic village of St. Imbenia are presented. (Author) 19 refs., 5 tabs., 8 figs

  4. Systemic complement activation in age-related macular degeneration.

    Hendrik P N Scholl

    Full Text Available Dysregulation of the alternative pathway (AP of complement cascade has been implicated in the pathogenesis of age-related macular degeneration (AMD, the leading cause of blindness in the elderly. To further test the hypothesis that defective control of complement activation underlies AMD, parameters of complement activation in blood plasma were determined together with disease-associated genetic markers in AMD patients. Plasma concentrations of activation products C3d, Ba, C3a, C5a, SC5b-9, substrate proteins C3, C4, factor B and regulators factor H and factor D were quantified in patients (n = 112 and controls (n = 67. Subjects were analyzed for single nucleotide polymorphisms in factor H (CFH, factor B-C2 (BF-C2 and complement C3 (C3 genes which were previously found to be associated with AMD. All activation products, especially markers of chronic complement activation Ba and C3d (p<0.001, were significantly elevated in AMD patients compared to controls. Similar alterations were observed in factor D, but not in C3, C4 or factor H. Logistic regression analysis revealed better discriminative accuracy of a model that is based only on complement activation markers Ba, C3d and factor D compared to a model based on genetic markers of the complement system within our study population. In both the controls' and AMD patients' group, the protein markers of complement activation were correlated with CFH haplotypes.This study is the first to show systemic complement activation in AMD patients. This suggests that AMD is a systemic disease with local disease manifestation at the ageing macula. Furthermore, the data provide evidence for an association of systemic activation of the alternative complement pathway with genetic variants of CFH that were previously linked to AMD susceptibility.

  5. Crystallization and X-ray diffraction analysis of the complement component-3 (C3) inhibitory domain of Efb from Staphylococcus aureus

    Hammel, Michal; Ramyar, Kasra X.; Spencer, Charles T.; Geisbrecht, Brian V.

    2006-01-01

    The crystallization and results of multiwavelength anomalous diffraction studies of a recombinant C3-inhibitory fragment of Efb from S. aureus are reported. The extracellular fibrinogen-binding protein (Efb) of Staphylococcus aureus is a multifunctional virulence factor capable of potent inhibition of complement component-3 (C3) activity in addition to its previously described fibrinogen-binding properties. A truncated recombinant form of Efb (Efb-C) that binds C3 has been overexpressed and purified and has been crystallized using the hanging-drop vapor-diffusion technique. Crystals of native Efb-C grew in the tetragonal space group P4 3 (unit-cell parameters a = b = 59.53, c = 46.63 Å) with two molecules in the asymmetric unit and diffracted well beyond 1.25 Å limiting Bragg spacing. To facilitate de novo phasing of the Efb-C crystals, two independent site-directed mutants were engineered in which either residue Ile112 or Val140 was replaced with methionine and crystals isomorphous to those of native Efb-C were reproduced using a seleno-l-methionine-labeled form of each mutant protein. Multiwavelength anomalous diffraction (MAD) data were collected on both mutants and analyzed for their phasing power toward solution and refinement of a high-resolution Efb-C crystal structure

  6. Major and minor elements analysis in soil samples by neutron activation analysis and X-ray fluorescence

    Morcelli, Claudia Petronilho Ribeiro; Ana Maria Graciano; Enzweiler, Jacinta

    2002-01-01

    In the present work, Instrumental Neutron Activation Analysis (INAA) and X-Ray Fluorescence were employed to analyze major and minor elements in soil samples collected near Bandeirantes road. Elements of environmental interest, such as Al, Sb, As, Ba, Cd, Pb, Co, Cu, Cr, Fe, Mn, Mo, Ni, Se, V and Zn, which have reference background levels, were determined. The samples were dried in an oven at 40 deg C, were sieved (<2 mm), grinded and were analyzed by INAA and FRX. The aims of this work were: to evaluate the possible variations in the concentration levels in soil due to emission of particulate from vehicles and other anthropogenic sources; to compare the results obtained by using both techniques. This preliminary study showed that the concentration levels of the elements of environmental interest agree with reference values for tropical soils in the sampling sites, except for Ba, which presented higher values. (author)

  7. A retrospective analysis of compact fluorescent lamp experience curves and their correlations to deployment programs

    Smith, Sarah Josephine; Wei, Max; Sohn, Michael D.

    2016-01-01

    Experience curves are useful for understanding technology development and can aid in the design and analysis of market transformation programs. Here, we employ a novel approach to create experience curves, to examine both global and North American compact fluorescent lamp (CFL) data for the years 1990–2007. We move away from the prevailing method of fitting a single, constant, exponential curve to data and instead search for break points where changes in the learning rate may have occurred. Our analysis suggests a learning rate of approximately 21% for the period of 1990–1997, and 51% and 79% in global and North American datasets, respectively, after 1998. We use price data for this analysis; therefore our learning rates encompass developments beyond typical “learning by doing”, including supply chain impacts such as market competition. We examine correlations between North American learning rates and the initiation of new programs, abrupt technological advances, and economic and political events, and find an increased learning rate associated with design advancements and federal standards programs. Our findings support the use of segmented experience curves for retrospective and prospective technology analysis, and may imply that investments in technology programs have contributed to an increase of the CFL learning rate. - Highlights: • We develop a segmented regression technique to estimate historical CFL learning curves. • CFL experience curves do not have a constant learning rate. • CFLs exhibited a learning rate of approximately 21% from 1990 to 1997. • The CFL learning rate significantly increased after 1998. • Increased CFL learning rate is correlated to technology deployment programs.

  8. Synchrotron Radiation Total Reflection X-ray Fluorescence Spectroscopy for Microcontamination Analysis on Silicon Wafer Surfaces

    Takaura, Norikatsu

    1997-10-01

    As dimensions in state-of-the-art CMOS devices shrink to less than 0.1 pm, even low levels of impurities on wafer surfaces can cause device degradation. Conventionally, metal contamination on wafer surfaces is measured using Total Reflection X-Ray Fluorescence Spectroscopy (TXRF). However, commercially available TXRF systems do not have the necessary sensitivity for measuring the lower levels of contamination required to develop new CMOS technologies. In an attempt to improve the sensitivity of TXRF, this research investigates Synchrotron Radiation TXRF (SR TXRF). The advantages of SR TXRF over conventional TXRF are higher incident photon flux, energy tunability, and linear polarization. We made use of these advantages to develop an optimized SR TXRF system at the Stanford Synchrotron Radiation Laboratory (SSRL). The results of measurements show that the Minimum Detection Limits (MDLs) of SR TXRF for 3-d transition metals are typically at a level-of 3x10{sup 8} atoms/cm{sup 2}, which is better than conventional TXRF by about a factor of 20. However, to use our SR TXRF system for practical applications, it was necessary to modify a commercially available Si (Li) detector which generates parasitic fluorescence signals. With the modified detector, we could achieve true MDLs of 3x10{sup 8} atoms/cm{sup 2} for 3-d transition metals. In addition, the analysis of Al on Si wafers is described. Al analysis is difficult because strong Si signals overlap the Al signals. In this work, the Si signals are greatly reduced by tuning the incident beam energy below the Si K edge. The results of our measurements show that the sensitivity for Al is limited by x-ray Raman scattering. Furthermore, we show the results of theoretical modeling of SR TXRF backgrounds consisting of the bremsstrahlung generated by photoelectrons, Compton scattering, and Raman scattering. To model these backgrounds, we extended conventional theoretical models by taking into account several aspects particular

  9. The lectin pathway of complement

    Ballegaard, Vibe Cecilie Diederich; Haugaard, Anna Karen; Garred, P

    2014-01-01

    The pattern recognition molecules of the lectin complement pathway are important components of the innate immune system with known functions in host-virus interactions. This paper summarizes current knowledge of how these intriguing molecules, including mannose-binding lectin (MBL), Ficolin-1, -2......-1, -2 and -3 and CL-11 could have similar functions in HIV infection as the ficolins have been shown to play a role in other viral infections, and CL-11 resembles MBL and the ficolins in structure and binding capacity.......The pattern recognition molecules of the lectin complement pathway are important components of the innate immune system with known functions in host-virus interactions. This paper summarizes current knowledge of how these intriguing molecules, including mannose-binding lectin (MBL), Ficolin-1, -2...

  10. Complement's participation in acquired immunity

    Nielsen, Claus Henrik; Leslie, Robert Graham Quinton

    2002-01-01

    of the B cell receptor for antigen (BCR), a complex composed of the iC3b/C3d fragment-binding complement type 2 receptor (CR2, CD21) and its signaling element CD19 and the IgG-binding receptor FcgammaRIIb (CD32). The positive or negative outcome of signaling through this triad is determined by the context...

  11. Comparative analysis of dose rates in bricks determined by neutron activation analysis, alpha counting and X-ray fluorescence analysis for the thermoluminescence fine grain dating method

    Bártová, H.; Kučera, Jan; Musílek, L.; Trojek, T.

    2014-01-01

    Roč. 104, NOV (2014), s. 393-397 ISSN 0969-806X. [1st International Conference on Dosimetry and its Applications (ICDA). Prague, 23.6.2013-28.6.2013] R&D Projects: GA MŠk(XE) LM2011019 Institutional support: RVO:61389005 Keywords : Alpha coutning * neutron activation analysis * X-ray fluorescence * thermoluminescence dating * dose rate Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.380, year: 2014

  12. Pigment particles analysis with a total reflection X-ray fluorescence spectrometer: study of influence of instrumental parameters

    Coccato, Alessia; Vandenabeele, Peter [Ghent University, Department of Archaeology, Ghent (Belgium); Vekemans, Bart; Vincze, Laszlo; Moens, Luc [Ghent University, Department of Analytical Chemistry, Ghent (Belgium)

    2016-12-15

    Total reflection X-ray fluorescence (TXRF) analysis is an excellent tool to determine major, minor and trace elements in minuscule amounts of samples, making this technique very suitable for pigment analysis. Collecting minuscule amounts of pigment material from precious works of art by means of a cotton swab is a well-accepted sampling method, but poses specific challenges when TXRF is to be used for the characterization of the unknown material. (orig.)

  13. Quantitative analysis by X-ray fluorescence using first principles for matrix correction

    Hulett, L.D.; Dunn, H.W.; Tarter, J.G.

    1978-01-01

    The quantitative interpretation of X-ray fluorescence (XRF) data is often difficult because of matrix effects. The intensity of fluorescence measured for a given element is not only dependent on the element's concentration, but also on the mass absorption coefficients of the sample for the excitation and fluorescence radiation. Also, there are interelement effects in which high-energy fluorescence from heavier elements is absorbed by lighter elements with a resulting enhancement of their fluorescence. Recent theoretical treatments of this problem have shown that X-ray fluorescence data can be corrected for these matrix effects by calculations based on first principles. Fundamental constants, available in atomic physics data tables, are the only parameters needed. It is not necessary to make empirical calibrations. The application of this correctional procedure to alloys and alumina-supported catalysts is described. A description is given of a low-background spectrometer which uses monochromatic Ag Ksub(α) radiation for excitation. Matrix corrections by first principles can be easily applied to data from instruments of this type because fluorescence excitation cross-sections and mass absorption coefficients can be accurately defined for monochromatic radiation. (author)

  14. Enhancing analysis of cells and proteins by fluorescence imaging on silk-based biomaterials: modulating the autofluorescence of silk.

    Neo, Puay Yong; Tan, Daryl Jian-An; Shi, Pujiang; Toh, Siew Lok; Goh, James Cho-Hong

    2015-02-01

    Silk is a versatile and established biomaterial for various tissue engineering purposes. However, it also exhibits strong autofluorescence signals-thereby hindering fluorescence imaging analysis of cells and proteins on silk-derived biomaterials. Sudan Black B (SB) is a lysochrome dye commonly used to stain lipids in histology. It has also been reported to be able to quench autofluorescence of tissues in histology and has been tested on artificial biomedical polymers in recent years. It was hypothesized that SB would exert similar quenching effects on silk, modulating the autofluorescence signals, and thereby enabling improved imaging analysis of cells and molecules of interests. The quenching effect of SB on the intrinsic fluorescence properties of silk and on commercial fluorescent dyes were first investigated in this study. SB was then incorporated into typical fluorescence-based staining protocols to study its effectiveness in improving fluorescence-based imaging of the cells and proteins residing with the silk-based biomaterials. Silk processed into various forms of biomaterials (e.g., films, sponges, fibers, and electrospun mats) was seeded with cells and cultured in vitro. At sacrificial time points, specimens were harvested, fixed, and prepared for fluorescence staining. SB, available commercially as a powder, was dissolved in 70% ethanol (0.3% [w/v]) to form staining solutions. SB treatment was introduced at the last step of typical immunofluorescence staining protocols for 15-120 min. For actin staining protocols by phalloidin toxin, SB staining solutions were added before and after permeabilization with Triton-X for 15-30 min. Results showed that ideal SB treatment duration is about 15 min. Apart from being able to suppress the autofluorescence of silk, this treatment duration was also not too long to adversely affect the fluorescent labeling probes used. The relative improvement brought about by SB treatment was most evident in the blue and green

  15. Meta-analysis assessing potential of steady-state chlorophyll fluorescence for remote sensing detection of plant water, temperature and nitrogen stress

    Ač, Alexander; Malenovský, Z.; Olejníčková, Julie; Gallé, A.; Rascher, U.; Mohammed, G.

    2015-01-01

    Roč. 168, oct (2015), s. 420-436 ISSN 0034-4257 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : steady-state chlorophyll fluorescence * passive sun-induced fluorescence * active laser-induced fluorescence * photosynthesis * stress * water * temperature * nitrogen * random-effects meta-analysis * FLEX satellite mission Subject RIV: EH - Ecology, Behaviour Impact factor: 5.881, year: 2015

  16. Analysis of skin tissues spatial fluorescence distribution by the Monte Carlo simulation

    Churmakov, D Y; Meglinski, I V; Piletsky, S A; Greenhalgh, D A

    2003-01-01

    A novel Monte Carlo technique of simulation of spatial fluorescence distribution within the human skin is presented. The computational model of skin takes into account the spatial distribution of fluorophores, which would arise due to the structure of collagen fibres, compared to the epidermis and stratum corneum where the distribution of fluorophores is assumed to be homogeneous. The results of simulation suggest that distribution of auto-fluorescence is significantly suppressed in the near-infrared spectral region, whereas the spatial distribution of fluorescence sources within a sensor layer embedded in the epidermis is localized at an 'effective' depth

  17. Analysis of skin tissues spatial fluorescence distribution by the Monte Carlo simulation

    Churmakov, D Y [School of Engineering, Cranfield University, Cranfield, MK43 0AL (United Kingdom); Meglinski, I V [School of Engineering, Cranfield University, Cranfield, MK43 0AL (United Kingdom); Piletsky, S A [Institute of BioScience and Technology, Cranfield University, Silsoe, MK45 4DT (United Kingdom); Greenhalgh, D A [School of Engineering, Cranfield University, Cranfield, MK43 0AL (United Kingdom)

    2003-07-21

    A novel Monte Carlo technique of simulation of spatial fluorescence distribution within the human skin is presented. The computational model of skin takes into account the spatial distribution of fluorophores, which would arise due to the structure of collagen fibres, compared to the epidermis and stratum corneum where the distribution of fluorophores is assumed to be homogeneous. The results of simulation suggest that distribution of auto-fluorescence is significantly suppressed in the near-infrared spectral region, whereas the spatial distribution of fluorescence sources within a sensor layer embedded in the epidermis is localized at an 'effective' depth.

  18. Analysis of skin tissues spatial fluorescence distribution by the Monte Carlo simulation

    Y Churmakov, D.; Meglinski, I. V.; Piletsky, S. A.; Greenhalgh, D. A.

    2003-07-01

    A novel Monte Carlo technique of simulation of spatial fluorescence distribution within the human skin is presented. The computational model of skin takes into account the spatial distribution of fluorophores, which would arise due to the structure of collagen fibres, compared to the epidermis and stratum corneum where the distribution of fluorophores is assumed to be homogeneous. The results of simulation suggest that distribution of auto-fluorescence is significantly suppressed in the near-infrared spectral region, whereas the spatial distribution of fluorescence sources within a sensor layer embedded in the epidermis is localized at an `effective' depth.

  19. Neutron, gamma and Roentgen fluorescent activation analysis of hair of children suffering from bronchial asthma

    Alekseeva, O.A.; Belov, A.G.; Frontasyeva, M.V.; Gundorina, S.F.; Gustova, M.V.; Kusmenko, L.G.; Perelygin, V.P.; Zaverioukha, O.S.

    2001-01-01

    The aim of present study was the multiparametric study of dangerous microelements content in the hair of children under school and primary school age which included 12 children ill with bronchial asthma and 11 control group persons in the town of Troitsk, Moscow Region. The hair specimens with weight 15-220 mg were analysed with the application of epithermal neutron activation analysis conducted at experimental installation REGATA and neutron source-unique Pulsed Fast Reactor IBR-2, with the application of combined gamma-neutron irradiation at Microtron MT-25 and with Roentgen Fluorescence Analysis device of JINR. The data of elements content in hair were obtained with solid state track detectors and semiconductor electronic spectrometers. The solid state track detectors provide the determination of U, Th, Bi and Be elements at the level of sensitivity up to 10 -8 -10 -9 g/g. These data were compared with more representative information about dangerous microelements concentration obtained with NAA and RFA analyses. The obtained concentrations of most elements vary in a wide range, but in agreement with the known data. The highest degree of element dispersion was observed for U, Th, Pb, I, Br, Sb, Co, K and Be (the radiation coefficient was higher than 100-200%). The presented analysis of results shows that in the clinical picture there is some proved correlation between an increased content of some element in hair and symptoms of their accumulation in the organism of ill children, the revelation of which is the basic idea of our examination

  20. Micro energy dispersive X-ray fluorescence analysis of polychrome lead-glazed Portuguese faiences

    Guilherme, A.; Pessanha, S.; Carvalho, M.L.; Santos, J.M.F. dos; Coroado, J.

    2010-01-01

    Several glazed ceramic pieces, originally produced in Coimbra (Portugal), were submitted to elemental analysis, having as premise the pigment manufacture production recognition. Although having been produced in Coimbra, their location changed as time passed due to historical reasons. A recent exhibition in Coimbra brought together a great number of these pieces and in situ micro Energy Dispersive X-ray Fluorescence (μ-EDXRF) analyses were performed in order to achieve some chemical and physical data on the manufacture of faiences in Coimbra. A non-commercial μ-EDXRF equipment for in situ analysis was employed in this work, carrying some important improvements when compared to the conventional ones, namely, analyzing spot sizes of about 100 μm diameter. The combination of a capillary X-ray lens with a new generation of low power microfocus X-ray tube and a drift chamber detector enabled a portable unit for micro-XRF with a few tens of μm lateral resolution. The advantages in using a portable system emphasized with polycapillary optics enabled to distinguish proximal different pigmented areas, as well as the glaze itself. These first scientific results on the pigment analysis of the collection of faiences seem to point to a unique production center with own techniques and raw materials. This conclusion arose with identification of the blue pigments having in its constitution Mn, Fe Co and As and the yellows as a result of the combination between Pb and Sb. A statistical treatment was used to reveal groups of similarities on the pigments elemental profile.

  1. Analysis of metal-laden water via portable X-ray fluorescence spectrometry

    Pearson, Delaina; Weindorf, David C.; Chakraborty, Somsubhra; Li, Bin; Koch, Jaco; Van Deventer, Piet; de Wet, Jandre; Kusi, Nana Yaw

    2018-06-01

    A rapid method for in-situ elemental composition analysis of metal-laden water would be indispensable for studying polluted water. Current analytical lab methods to determine water quality include flame atomic absorption spectrometry (FAAS), atomic absorption spectrophotometry (AAS), electrothermal atomic absorption spectrometry (EAAS), and inductively coupled plasma (ICP) spectroscopy. However only two field methods, colorimetry and absorptiometry, exist for elemental analysis of water. Portable X-ray fluorescence (PXRF) spectrometry is an effective method for elemental analysis of soil, sediment, and other matrices. However, the accuracy of PXRF is known to be affected while scanning moisture-laden soil samples. This study sought to statistically establish PXRF's predictive ability for various elements in water at different concentrations relative to inductively coupled plasma atomic emission spectroscopy (ICP-AES). A total of 390 metal-laden water samples collected from leaching columns of mine tailings in South Africa were analyzed via PXRF and ICP-AES. The PXRF showed differential effectiveness in elemental quantification. For the collected water samples, the best relationships between ICP and PXRF elemental data were obtained for K and Cu (R2 = 0.92). However, when scanning ICP calibration solutions with elements in isolation, PXRF results indicated near perfect agreement; Ca, K, Fe, Cu and Pb produced an R2 of 0.99 while Zn and Mn produced an R2 of 1.00. The utilization of multiple PXRF (stacked) beams produced stronger correlation to ICP relative to the use of a single beam in isolation. The results of this study demonstrated the PXRF's ability to satisfactorily predict the composition of metal-laden water as reported by ICP for several elements. Additionally this study indicated the need for a "Water Mode" calibration for the PXRF and demonstrates the potential of PXRF for future study of polluted or contaminated waters.

  2. Total protein analysis as a reliable loading control for quantitative fluorescent Western blotting.

    Samantha L Eaton

    Full Text Available Western blotting has been a key technique for determining the relative expression of proteins within complex biological samples since the first publications in 1979. Recent developments in sensitive fluorescent labels, with truly quantifiable linear ranges and greater limits of detection, have allowed biologists to probe tissue specific pathways and processes with higher resolution than ever before. However, the application of quantitative Western blotting (QWB to a range of healthy tissues and those from degenerative models has highlighted a problem with significant consequences for quantitative protein analysis: how can researchers conduct comparative expression analyses when many of the commonly used reference proteins (e.g. loading controls are differentially expressed? Here we demonstrate that common controls, including actin and tubulin, are differentially expressed in tissues from a wide range of animal models of neurodegeneration. We highlight the prevalence of such alterations through examination of published "-omics" data, and demonstrate similar responses in sensitive QWB experiments. For example, QWB analysis of spinal cord from a murine model of Spinal Muscular Atrophy using an Odyssey scanner revealed that beta-actin expression was decreased by 19.3±2% compared to healthy littermate controls. Thus, normalising QWB data to β-actin in these circumstances could result in 'skewing' of all data by ∼20%. We further demonstrate that differential expression of commonly used loading controls was not restricted to the nervous system, but was also detectable across multiple tissues, including bone, fat and internal organs. Moreover, expression of these "control" proteins was not consistent between different portions of the same tissue, highlighting the importance of careful and consistent tissue sampling for QWB experiments. Finally, having illustrated the problem of selecting appropriate single protein loading controls, we demonstrate

  3. Amine Analysis Using AlexaFluor 488 Succinimidyl Ester and Capillary Electrophoresis with Laser-Induced Fluorescence

    Christian G. Kendall

    2015-01-01

    Full Text Available Fluorescent probes enable detection of otherwise nonfluorescent species via highly sensitive laser-induced fluorescence. Organic amines are predominantly nonfluorescent and are of analytical interest in agricultural and food science, biomedical applications, and biowarfare detection. Alexa Fluor 488 N-hydroxysuccinimidyl ester (AF488 NHS-ester is an amine-specific fluorescent probe. Here, we demonstrate low limit of detection of long-chain (C9 to C18 primary amines and optimize AF488 derivatization of long-chain primary amines. The reaction was found to be equally efficient in all solvents studied (dimethylsulfoxide, ethanol, and N,N-dimethylformamide. While an organic base (N,N-diisopropylethylamine is required to achieve efficient reaction between AF488 NHS-ester and organic amines with longer hydrophobic chains, high concentrations (>5 mM result in increased levels of ethylamine and propylamine in the blank. Optimal incubation times were found to be >12 hrs at room temperature. We present an initial capillary electrophoresis separation for analysis using a simple micellar electrokinetic chromatography (MEKC buffer consisting of 12 mM sodium dodecylsulfate (SDS and 5 mM carbonate, pH 10. Limits of detection using the optimized labeling conditions and these separation conditions were 5–17 nM. The method presented here represents a novel addition to the arsenal of fluorescent probes available for highly sensitive analysis of small organic molecules.

  4. A low cost multi-purpose experimental arrangement for variants in energy dispersive X-ray fluorescence analysis

    Nascimento Filho, V.F.; Silva, R.M.C.; Moraes, L.M.B.; Parreira, P.S.; Appoloni, R.C.; Silva, R.M.C.

    2005-01-01

    Based in an X-ray tower with four exits (two line and two point beams) experimental conditions were arranged to carry out variants in energy dispersive X-ray fluorescence analysis: (1) the conventional one (EDXRF), with excitation/detection of thin and thick samples, under vacuum and air atmosphere, (2) the X-ray energy dispersive micro- fluorescence analysis(μ-EDXRF), with 2D mapping, using a quartz capillar, (3) the total reflection X-ray fluorescence (TXRF), under He and air atmosphere, and (4) secondary target/polarized X-ray fluorescence (P-EDXRF). It was possible to use a Cu, Mo or W target on the X-ray tube, with or without filter (V, Fe, Ni and Zr), and Si(Li) or Si-PIN semicondutor detectors coupled to a multichannel analyzer. In addition, it was possible to use the point beam to carry out experiments on (5) X-ray radiography and (6) X-ray absorption, and the line beam on (7) X-ray diffractometry studies.

  5. Water deficit and salt stress diagnosis through LED induced chlorophyll fluorescence analysis in Jatropha curcas L. oil plants for biodiesel

    Gouveia-Neto, Artur S.; Silva, Elias A., Jr.; Oliveira, Ronaldo A.; Cunha, Patrícia C.; Costa, Ernande B.; Câmara, Terezinha J. R.; Willadino, Lilia G.

    2011-02-01

    Light-emitting-diode induced chlorophyll fluorescence analysis is employed to investigate the effect of water and salt stress upon the growth process of physicnut(jatropha curcas) grain oil plants for biofuel. Red(Fr) and far-red (FFr) chlorophyll fluorescence emission signals around 685 nm and 735 nm, respectively, were observed and examined as a function of the stress intensity(salt concentration and water deficit) for a period of time of 30 days. The chlorophyll fluorescence(ChlF) ratio Fr/FFr which is a valuable nondestructive and nonintrusive indicator of the chlorophyll content of leaves was exploited to monitor the level of stress experienced by the jatropha plants. The ChlF technique data indicated that salinity plays a minor role in the chlorophyll concentration of leaves tissues for NaCl concentrations in the 25 to 200 mM range, and results agreed quite well with those obtained using conventional destructive spectrophotometric methods. Nevertheless, for higher NaCl concentrations a noticeable decrease in the Chl content was observed. The Chl fluorescence ratio analysis also permitted detection of damage caused by water deficit in the early stages of the plants growing process. A significant variation of the Fr/FFr ratio was observed sample in the first 10 days of the experiment when one compared control and nonwatered samples. The results suggest that the technique may potentially be applied as an early-warning indicator of stress caused by water deficit.

  6. Analysis of DNA binding by human factor xeroderma pigmentosum complementation group A (XPA) provides insight into its interactions with nucleotide excision repair substrates.

    Sugitani, Norie; Voehler, Markus W; Roh, Michelle S; Topolska-Woś, Agnieszka M; Chazin, Walter J

    2017-10-13

    Xeroderma pigmentosum (XP) complementation group A (XPA) is an essential scaffolding protein in the multiprotein nucleotide excision repair (NER) machinery. The interaction of XPA with DNA is a core function of this protein; a number of mutations in the DNA-binding domain (DBD) are associated with XP disease. Although structures of the central globular domain of human XPA and data on binding of DNA substrates have been reported, the structural basis for XPA's DNA-binding activity remains unknown. X-ray crystal structures of the central globular domain of yeast XPA (Rad14) with lesion-containing DNA duplexes have provided valuable insights, but the DNA substrates used for this study do not correspond to the substrates of XPA as it functions within the NER machinery. To better understand the DNA-binding activity of human XPA in NER, we used NMR to investigate the interaction of its DBD with a range of DNA substrates. We found that XPA binds different single-stranded/double-stranded junction DNA substrates with a common surface. Comparisons of our NMR-based mapping of binding residues with the previously reported Rad14-DNA crystal structures revealed similarities and differences in substrate binding between XPA and Rad14. This includes direct evidence for DNA contacts to the residues extending C-terminally from the globular core, which are lacking in the Rad14 construct. Moreover, mutation of the XPA residue corresponding to Phe-262 in Rad14, previously reported as being critical for DNA binding, had only a moderate effect on the DNA-binding activity of XPA. The DNA-binding properties of several disease-associated mutations in the DBD were investigated. These results suggest that for XPA mutants exhibiting altered DNA-binding properties, a correlation exists between the extent of reduction in DNA-binding affinity and the severity of symptoms in XP patients. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. The analysis of anode sludges by x-ray-fluorescence spectrometry

    Austen, C.E.; Wall, G.J.

    1978-01-01

    A method is described for the analysis, by X-ray-fluorescence spectrometry, of anode sludges for the determination of antimony, bismuth, copper, iron, lead, nickel, selenium, silver, tellurium, tin, and zinc. The preparation of the samples involves fusion with a flux of barium peroxide and lithium hydroxide, and with dichromium trioxide as the internal standard, in a zirconium or vitreous-carbon crucible and casting of the melt in an aluminium mould; the fused disc so formed is then pulverized and briquetted to form pellets. Calibration curves, which are straight lines for all the elemets determined because the flux contains a heavy absorber, are established by measurement of pellets prepared from standard anode sludges, pure metals, compounds of the metals, or any combination of these materials. The precision of the results varies between 2 and 15 per cent relative standard deviation, depending on the concentration of the element being determined. The accuracy of the results is comparable with that obtained by wet-chemical methods. The laboratory method is given in an appendix

  8. Censoring approach to the detection limits in X-ray fluorescence analysis

    Pajek, M.; Kubala-Kukus, A.

    2004-01-01

    We demonstrate that the effect of detection limits in the X-ray fluorescence analysis (XRF), which limits the determination of very low concentrations of trace elements and results in appearance of the so-called 'nondetects', can be accounted for using the statistical concept of censoring. More precisely, the results of such measurements can be viewed as the left random censored data, which can further be analyzed using the Kaplan-Meier method correcting the data for the presence of nondetects. Using this approach, the results of measured, detection limit censored concentrations can be interpreted in a nonparametric manner including the correction for the nondetects, i.e. the measurements in which the concentrations were found to be below the actual detection limits. Moreover, using the Monte Carlo simulation technique we show that by using the Kaplan-Meier approach the corrected mean concentrations for a population of the samples can be estimated within a few percent uncertainties with respect of the simulated, uncensored data. This practically means that the final uncertainties of estimated mean values are limited in fact by the number of studied samples and not by the correction procedure itself. The discussed random-left censoring approach was applied to analyze the XRF detection-limit-censored concentration measurements of trace elements in biomedical samples

  9. Analysis of azaarenes in pan fried meat and its gravy by liquid chromatography with fluorescence detection.

    Błaszczyk, Urszula; Janoszka, Beata

    2008-07-01

    A method for analysis of six azaarenes (benzo[h]quinoline, benzo[a]acridine, benzo[c]acridine, dibenzo[a,c]acridine, dibenzo[a,j]acridine and dibenzo[a,h]acridine) in thermally treated high-protein food has been described. The clean-up procedure used based on alkaline hydrolysis, tandem solid phase extraction on columns filled with Extrelut - diatomaceous earth and cation exchanger (propyl sulfonic acid), enabled a selective isolation of carcinogenic compounds belonging to benzoacridines and dibenzoacridines from samples of cooked meat and its gravy. The isolated fractions of aza-PAHs were analysed by high-performance liquid chromatography with fluorescence detection. The detection limits for the azaarenes were between 0.0001ng and 0.005ng loaded on column. The recoveries for the four-ring and five-ring azaarenes were from 55% to 67%. Two types of dishes prepared from pork by pan-frying were investigated. Total contents of the benzoacridines and dibenzoacridines determined in cooked meat were 1.57 and 2.50ng/g in collar and chop samples, respectively; their gravies contained 0.34 and 0.59ng of these azaarenes per g of cooked meat. Copyright © 2007 Elsevier Ltd. All rights reserved.

  10. X-ray fluorescence analysis of strontium in environmental water by using barium carbonate coprecipitation method

    Nishioka, Hiroshi; Yoneda, Akio; Maeda, Yoshimichi; Azumi, Takatugu

    1986-01-01

    Determination of strontium in environmental water was studied by a coprecipitation method with barium carbonate and the subsequent X-ray fluorescence analysis. Fifty mg of barium ion and 1 g of sodium carbonate were added to sample water, which was then mixed for one hour by a magnetic stirrer. Precipitate was gathered onto a membrane filter paper to measure its XF intensity. The amount of strontium from 2 to 150 μg could be repeatedly determined by means of the calibration curve method, and the limit of detection was found to be 0.6 μg of strontium. A large amount of calcium and magnesium ions was found to interfere with the coprecipitation of strontium ion. However, this interference could be eliminated by using a small amount of sample water. Strontium in several environmental waters was determined by the above method. The results obtained from the calibration curve method and the standard addition method agreed with each other, and also agreed with those from the atomic absorption spectrometry. (author)

  11. X-ray fluorescence and computed radiography analysis of a famous brazilian painting from XIX century

    Calza, Cristiane; Oliveira, Davi F.; Rocha, Henrique S.; Lopes, Ricardo Tadeu

    2009-01-01

    This work used Energy Dispersive X-Ray Fluorescence (EDXRF) and Computed Radiography (CR) to evaluate the general conditions of the painting 'Gioventu' (Eliseu Visconti, 1898), identifying possible problems, areas that revealed signs of previous retouchings and the pigments used by the artist. EDXRF measurements were carried out with a portable system consisting of an X-ray tube Oxford TF3005 with W anode, operating at 25 kV and 100 μA, and a Si-PIN XR-100CR detector from Amptek. Several spectra were obtained in each color, with an acquisition time of 300 s and a beam collimation of 2 mm. The spectra were analyzed using the software QXAS-AXIL (IAEA). The results revealed that the drawings were made over a preparatory layer of lead white. Some pigments identified were: yellow, red and brown ochre; umbra; vermilion; cobalt blue; etc. The experimental setup used in the CR analysis consisted of an Oxford X-ray source, operating at 50 kV and 200 μA, placed at 85 cm from the painting, a GE CR 50P portable computed radiography scanner and a Fuji imaging plate detector. The exposure time was 600 s. The radiographic images revealed that the painting was in a good state of conservation and also a complete composition hidden underneath the visible paint layer.(author)

  12. Total Reflection X-ray Fluorescence attachment module modified for analysis in vacuum

    Wobrauschek, P.; Streli, C.; Kregsamer, P.; Meirer, F.; Jokubonis, C.; Markowicz, A.; Wegrzynek, D.; Chinea-Cano, E.

    2008-01-01

    Based on the design of the low cost Total Reflection X-Ray Fluorescence attachment module available since 1986 from Atominstitut (WOBRAUSCHEK-module) which can be attached to existing X-ray equipment, a new version was developed which allows the analysis of samples in vacuum. This design was in particular possible as the Peltier cooled light weight Silicon Drift Detector is following all adjustment procedures for total reflection as angle rotation and linear motion. The detector is mounted through a vacuum feed and O-ring tightening to the small vacuum chamber. The standard 30 mm round quartz, Si-wafer or Plexiglas reflectors are used to carry the samples. The reflectors are placed on the reference plane with the dried sample down looking facing in about 0.5 mm distance the up looking detector window. The reflectors are resting on 3 steel balls defining precisely the reference plane for the adjustment procedure. As the rotation axis of the module is in the plane of the reflector surface, angle dependent experiments can be made to distinguish between film and particulate type contamination of samples. Operating with a Mo anode at 50 kV and 40 mA with a closely attached multilayer monochromator and using a 10 mm 2 KETEK silicon drift detector with 8 μm Be window, a sensitivity of 70 cps/ng for Rb was measured and detection limits of 2 pg were obtained

  13. Applications of a glazing incidence X-ray fluorescence analysis to forensic samples

    Ninomiya, Toshio; Nomura, Shigeaki; Taniguchi, Kazuo; Ikeda, Shigero.

    1995-01-01

    A glazing incidence X-ray fluorescence analysis (GIXF) has been applied to forensic samples: a counterfeit 100-dollar bill, fragments of polyvinyl tapes, a trace of semen, illegal drugs, fingerprints and fake V.S.O.P brandy. Strontium could not be detected on the magnet-respondent letter of the counterfeit bill and Br was detected on the magnet-nonrespondent part of the counterfeit bill, while such phenomena could not be noticed on a true bill. Fragments of black vinyl tapes related to a sexual assault case could be discriminated from each other. Zinc as a characteristic ingredient could be detected in a trace of semen. Bromine was detected in each of what is called a pure methamphetamine crystal and K, Ca, Fe, Zn etc. were detected in heroin powders. Lead was sharply detected in gunshot residues attached to a finger after gunfiring. Sulfur as a contaminant was abundant in fake V.S.O.P brandy, while no S was detected in genuine V.S.O.P brandy. (author)

  14. Applications of a glazing incidence X-ray fluorescence analysis to forensic samples

    Ninomiya, Toshio [Hyogo Prefecture, Kobe (Japan). Forensic Science Lab.; Nomura, Shigeaki; Taniguchi, Kazuo; Ikeda, Shigero

    1995-06-01

    A glazing incidence X-ray fluorescence analysis (GIXF) has been applied to forensic samples: a counterfeit 100-dollar bill, fragments of polyvinyl tapes, a trace of semen, illegal drugs, fingerprints and fake V.S.O.P brandy. Strontium could not be detected on the magnet-respondent letter of the counterfeit bill and Br was detected on the magnet-nonrespondent part of the counterfeit bill, while such phenomena could not be noticed on a true bill. Fragments of black vinyl tapes related to a sexual assault case could be discriminated from each other. Zinc as a characteristic ingredient could be detected in a trace of semen. Bromine was detected in each of what is called a pure methamphetamine crystal and K, Ca, Fe, Zn etc. were detected in heroin powders. Lead was sharply detected in gunshot residues attached to a finger after gunfiring. Sulfur as a contaminant was abundant in fake V.S.O.P brandy, while no S was detected in genuine V.S.O.P brandy. (author).

  15. Tar analysis from biomass gasification by means of online fluorescence spectroscopy

    Baumhakl, Christoph; Karellas, Sotirios

    2011-07-01

    Optical methods in gas analysis are very valuable mainly due to their non-intrusive character. That gives the possibility to use them for in-situ or online measurements with only optical intervention in the measurement volume. In processes like the gasification of biomass, it is of high importance to monitor the gas quality in order to use the product gas in proper machines for energy production following the restrictions in the gas composition but also improving its quality, which leads to high efficient systems. One of the main problems in the biomass gasification process is the formation of tars. These higher hydrocarbons can lead to problems in the operation of the energy system. Up to date, the state of the art method used widely for the determination of tars is a standardized offline measurement system, the so-called "Tar Protocol". The aim of this work is to describe an innovative, online, optical method for determining the tar content of the product gas by means of fluorescence spectroscopy. This method uses optical sources and detectors that can be found in the market at low cost and therefore it is very attractive, especially for industrial applications where cost efficiency followed by medium to high precision are of high importance.

  16. 5-ALA Fluorescence Image Guided Resection of Glioblastoma Multiforme: A Meta-Analysis of the Literature

    Samy Eljamel

    2015-05-01

    Full Text Available Background: Glioblastoma multiforme (GBM is one of the most deadly cancers in humans. Despite recent advances in anti-cancer therapies, most patients with GBM die from local disease progression. Fluorescence image guided surgical resection (FIGR was recently advocated to enhance local control of GBM. This is meta-analyses of 5-aminolevulinic (5-ALA induced FIGR. Materials: Review of the literature produced 503 potential publications; only 20 of these fulfilled the inclusion criteria of this analysis, including a total of 565 patients treated with 5-ALA-FIGR reporting on its outcomes and 800 histological samples reporting 5-ALA-FIGR sensitivity and specificity. Results: The mean gross total resection (GTR rate was 75.4% (95% CI: 67.4–83.5, p < 0.001. The mean time to tumor progression (TTP was 8.1 months (95% CI: 4.7–12, p < 0.001. The mean overall survival gain reported was 6.2 months (95% CI: −1–13, p < 0.001. The specificity was 88.9% (95% CI: 83.9–93.9, p < 0.001 and the sensitivity was 82.6% (95% CI: 73.9–91.9, p < 0.001. Conclusion: 5-ALA-FIGR in GBM is highly sensitive and specific, and imparts significant benefits to patients in terms of improved GTR and TTP.

  17. Sample preparation for total reflection X-ray fluorescence analysis using resist pattern technique

    Tsuji, K.; Yomogita, N.; Konyuba, Y.

    2018-06-01

    A circular resist pattern layer with a diameter of 9 mm was prepared on a glass substrate (26 mm × 76 mm; 1.5 mm thick) for total reflection X-ray fluorescence (TXRF) analysis. The parallel cross pattern was designed with a wall thickness of 10 μm, an interval of 20 μm, and a height of 1.4 or 0.8 μm. This additional resist layer did not significantly increase background intensity on the XRF peaks in TXRF spectra. Dotted residue was obtained from a standard solution (10 μL) containing Ti, Cr, Ni, Pb, and Ga, each at a final concentration of 10 ppm, on a normal glass substrate with a silicone coating layer. The height of the residue was more than 100 μm, where self-absorption in the large residue affected TXRF quantification (intensity relative standard deviation (RSD): 12-20%). In contrast, from a droplet composed of a small volume of solution dropped and cast on the resist pattern structure, the obtained residue was not completely film but a film-like residue with a thickness less than 1 μm, where self-absorption was not a serious problem. In the end, this sample preparation was demonstrated to improve TXRF quantification (intensity RSD: 2-4%).

  18. Multiplex fluorescence melting curve analysis for mutation detection with dual-labeled, self-quenched probes.

    Qiuying Huang

    2011-04-01

    Full Text Available Probe-based fluorescence melting curve analysis (FMCA is a powerful tool for mutation detection based on melting temperature generated by thermal denaturation of the probe-target hybrid. Nevertheless, the color multiplexing, probe design, and cross-platform compatibility remain to be limited by using existing probe chemistries. We hereby explored two dual-labeled, self-quenched probes, TaqMan and shared-stem molecular beacons, in their ability to conduct FMCA. Both probes could be directly used for FMCA and readily integrated with closed-tube amplicon hybridization under asymmetric PCR conditions. Improved flexibility of FMCA by using these probes was illustrated in three representative applications of FMCA: mutation scanning, mutation identification and mutation genotyping, all of which achieved improved color-multiplexing with easy probe design and versatile probe combination and all were validated with a large number of real clinical samples. The universal cross-platform compatibility of these probes-based FMCA was also demonstrated by a 4-color mutation genotyping assay performed on five different real-time PCR instruments. The dual-labeled, self-quenched probes offered unprecedented combined advantage of enhanced multiplexing, improved flexibility in probe design, and expanded cross-platform compatibility, which would substantially improve FMCA in mutation detection of various applications.

  19. Collection of airborne particulate matter for a subsequent analysis by total reflection X-ray fluorescence

    Klockenkaemper, R.; Bayer, H.; Bohlen, A. von; Schmeling, M.; Klockow, D.

    1995-01-01

    The collection of airborne particulate matter by filtration and impaction was adapted to total reflection X-ray fluorescence analysis (TXRF). Cellulose nitrate filters were used for collecting in a Berner impactor. Single filter spots were punched out, placed on quartz-glass carriers, dissolved by tetrahydrofuran and re-precipitated prior to element determinations by TXRF. In a Battelle-type impactor, airborne dust was collected on Plexiglass carriers coated with medical Vaseline. The loaded carriers were directly analyzed by TXRF. In both cases, quantification was simply performed by the addition of an internal standard after sampling. Impactors were made of a suitable material in order to investigate high blank values, collection losses and memory effects. It could be shown that stainless steel, even coated with TiN, is less suitable and should be avoided as an impactor material. Although aluminum is partly recommendable, titanium and the polymer Makrolon are quite appropriate. By using an impactor made of these materials, a reliable multielement determination in airborne dust is made possible with low detection limits as low as 1 ng/m 3 and a satisfactory repeatability of a few %. Short sampling times of only 1 h or less can be realized. The total procedure is simple and time-saving, and can be recommended for routine investigations of airborne particulate matter. (author)

  20. X-ray fluorescence and computed radiography analysis of a famous brazilian painting from XIX century

    Calza, Cristiane; Oliveira, Davi F.; Rocha, Henrique S.; Lopes, Ricardo Tadeu [Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Instrumentacao Nuclear], e-mail: ccalza@lin.ufrj.br; Pedreira, Andrea [Museu Nacional de Belas Artes, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This work used Energy Dispersive X-Ray Fluorescence (EDXRF) and Computed Radiography (CR) to evaluate the general conditions of the painting 'Gioventu' (Eliseu Visconti, 1898), identifying possible problems, areas that revealed signs of previous retouchings and the pigments used by the artist. EDXRF measurements were carried out with a portable system consisting of an X-ray tube Oxford TF3005 with W anode, operating at 25 kV and 100 {mu}A, and a Si-PIN XR-100CR detector from Amptek. Several spectra were obtained in each color, with an acquisition time of 300 s and a beam collimation of 2 mm. The spectra were analyzed using the software QXAS-AXIL (IAEA). The results revealed that the drawings were made over a preparatory layer of lead white. Some pigments identified were: yellow, red and brown ochre; umbra; vermilion; cobalt blue; etc. The experimental setup used in the CR analysis consisted of an Oxford X-ray source, operating at 50 kV and 200 {mu}A, placed at 85 cm from the painting, a GE CR 50P portable computed radiography scanner and a Fuji imaging plate detector. The exposure time was 600 s. The radiographic images revealed that the painting was in a good state of conservation and also a complete composition hidden underneath the visible paint layer.(author)

  1. Redox speciation analysis of antimony in soil extracts by hydride generation atomic fluorescence spectrometry

    Fuentes, Edwar; Pinochet, Hugo; Gregori, Ida de; Potin-Gautier, Martine

    2003-01-01

    A sensitive atomic spectrometric method for the redox speciation analysis of antimony in soils is described. The method is based on the selective generation of stibine from Sb(III) in a continuous flow system using atomic fluorescence spectrometry for detection. Sb(V) is masked by citric or oxalic acid in HCl medium. The procedure was optimized with synthetic solutions of Sb(III) and Sb(V). The effect of carboxylic acid and HCl concentration on the recovery of Sb(III) and Sb(V) species from standard solutions, and on the fluorescence signal were studied. Both species were extracted from soil with H 2 O, 0.05 mol l -1 EDTA and 0.25 mol l -1 H 2 SO 4 . Since the soil samples were collected from sites impacted by copper mining activities, the effect of Cu 2+ on the determination of antimony in synthetic solutions and soil extracts was studied. Cu 2+ decreased the Sb(III) signal, but had no effect on the total antimony determination. Therefore, the selective determination of Sb(III) was carried out in citric acid-HCl medium, using the analyte addition technique. Total antimony in soil extracts was determined using the standard calibration technique after reducing Sb(V) to Sb(III) at room temperature with KI-ascorbic acid. The Sb(V) concentration was calculated from the difference between total antimony and Sb(III). The limits of detection (PS Analytical, Excalibur Millennium model) were 17 and 10 ng l -1 for Sb(III) and total antimony, respectively, and the R.S.D. at the 0.5-μg l -1 level were 2.5 and 2.4%, respectively. The total antimony concentration of soils is in the mg kg -1 range; the Sb recovery from the different soils by the extracting solutions was between less than 0.02% and approximately 10%. Similar recoveries were obtained using EDTA and sulfuric acid solutions. Sb(V) was found to be the main antimony species extracted from soils

  2. Applicability of multisyringe chromatography coupled to cold-vapor atomic fluorescence spectrometry for mercury speciation analysis

    Guzmán-Mar, J.L.; Hinojosa-Reyes, L.; Serra, A.M.; Hernández-Ramírez, A.; Cerdà, V.

    2011-01-01

    Graphical abstract: An automatic system, based on the applicability of multisyringe chromatography (MSC) coupled to cold-vapor atomic fluorescence spectrometry (CV/AFS) detection is developed for mercury speciation. Highlights: ► The on-line coupling of MSC to CV/AFS was developed for mercury speciation analysis. ► The speciation of MeHg + , Hg 2+ and EtHg + was achieved on a RP C18 monolithic column. ► The hyphenated system provided higher sample throughput compared to HPLC–CV/AFS. ► The limits of detection for mercury species were comparable or better than those reported by HPLC–CV/AFS. ► The developed method also provided low instrumental and operational costs. - Abstract: In this paper, a novel automatic approach for the speciation of inorganic mercury (Hg 2+ ), methylmercury (MeHg + ) and ethylmercury (EtHg + ) using multisyringe chromatography (MSC) coupled to cold-vapor atomic fluorescence spectrometry (CV/AFS) was developed. For the first time, the separation of mercury species was accomplished on a RP C18 monolithic column using a multi-isocratic elution program. The elution protocol involved the use of 0.005% 2-mercapthoethanol in 240 mM ammonium acetate (pH 6)–acetonitrile (99:1, v/v), followed by 0.005% 2-mercapthoethanol in 240 mM ammonium acetate (pH 6)–acetonitrile (90:10, v/v). The eluted mercury species were then oxidized under post-column UV radiation and reduced using tin(II) chloride in an acidic medium. Subsequently, the generated mercury metal were separated from the reaction mixture and further atomized in the flame atomizer and detected by AFS. Under the optimized experimental conditions, the limits of detection (3σ) were found to be 0.03, 0.11 and 0.09 μg L −1 for MeHg + , Hg 2+ and EtHg + , respectively. The relative standard deviation (RSD, n = 6) of the peak height for 3, 6 and 3 μg L −1 of MeHg + , Hg 2+ and EtHg + (as Hg) ranged from 2.4 to 4.0%. Compared with the conventional HPLC–CV/AFS hyphenated systems

  3. Evaluation of a tungsten coil atomization-laser-induced fluorescence detection approach for trace elemental analysis

    Ezer, Muhsin; Elwood, Seth A.; Jones, Bradley T.; Simeonsson, Josef B.

    2006-01-01

    The analytical utility of a tungsten (W)-coil atomization-laser-induced fluorescence (LIF) approach has been evaluated for trace level measurements of elemental chromium (Cr), arsenic (As), selenium (Se), antimony (Sb), lead (Pb), tin (Sn), copper (Cu), thallium (Tl), indium (In), cadmium (Cd), zinc (Zn) and mercury (Hg). Measurements of As, Cr, In, Se, Sb, Pb, Tl, and Sn were performed by laser-induced fluorescence using a single dye laser operating near 460 nm whose output was converted by frequency doubling and stimulated Raman scattering to wavelengths ranging from 196 to 286 nm for atomic excitation. Absolute limits of detection (LODs) of 1, 0.3, 0.3, 0.2, 1, 6, 1, 0.2 and 0.8 pg and concentration LODs of 100, 30, 30, 20, 100, 600, 100, 20, and 80 pg/mL were achieved for As, Se, Sb, Sn, In, Cu, Cr, Pb and Tl, respectively. Determinations of Hg, Pb, Zn and Cd were performed using two-color excitation approaches and resulted in absolute LODs of 2, 30, 5 and 0.6 pg, respectively, and concentration LODs of 200, 3000, 500 and 60 pg/mL, respectively. The sensitivities achieved by the W-coil LIF approaches compare well with those reported by W-coil atomic absorption spectrometry, graphite furnace atomic absorption spectrometry, and graphite furnace electrothermal atomization-LIF approaches. The accuracy of the approach was verified through the analysis of a multielement reference solution containing Sb, Pb and Tl which each had certified performance acceptance limits of 19.6-20.4 μg/mL. The determined concentrations were 20.05 ± 2.60, 20.70 ± 2.27 and 20.60 ± 2.46 μg/mL, for Sb, Pb and Tl, respectively. The results demonstrate that W-coil LIF provides good analytical performance for trace analyses due to its high sensitivity, linearity, and capability to measure multiple elements using a single tunable laser and suggest that the development of portable W-coil LIF instrumentation using compact, solid-state lasers is feasible

  4. Evaluation of a tungsten coil atomization-laser-induced fluorescence detection approach for trace elemental analysis.

    Ezer, Muhsin; Elwood, Seth A; Jones, Bradley T; Simeonsson, Josef B

    2006-06-30

    The analytical utility of a tungsten (W)-coil atomization-laser-induced fluorescence (LIF) approach has been evaluated for trace level measurements of elemental chromium (Cr), arsenic (As), selenium (Se), antimony (Sb), lead (Pb), tin (Sn), copper (Cu), thallium (Tl), indium (In), cadmium (Cd), zinc (Zn) and mercury (Hg). Measurements of As, Cr, In, Se, Sb, Pb, Tl, and Sn were performed by laser-induced fluorescence using a single dye laser operating near 460 nm whose output was converted by frequency doubling and stimulated Raman scattering to wavelengths ranging from 196 to 286 nm for atomic excitation. Absolute limits of detection (LODs) of 1, 0.3, 0.3, 0.2, 1, 6, 1, 0.2 and 0.8 pg and concentration LODs of 100, 30, 30, 20, 100, 600, 100, 20, and 80 pg/mL were achieved for As, Se, Sb, Sn, In, Cu, Cr, Pb and Tl, respectively. Determinations of Hg, Pb, Zn and Cd were performed using two-color excitation approaches and resulted in absolute LODs of 2, 30, 5 and 0.6 pg, respectively, and concentration LODs of 200, 3000, 500 and 60 pg/mL, respectively. The sensitivities achieved by the W-coil LIF approaches compare well with those reported by W-coil atomic absorption spectrometry, graphite furnace atomic absorption spectrometry, and graphite furnace electrothermal atomization-LIF approaches. The accuracy of the approach was verified through the analysis of a multielement reference solution containing Sb, Pb and Tl which each had certified performance acceptance limits of 19.6-20.4 microg/mL. The determined concentrations were 20.05+/-2.60, 20.70+/-2.27 and 20.60+/-2.46 microg/mL, for Sb, Pb and Tl, respectively. The results demonstrate that W-coil LIF provides good analytical performance for trace analyses due to its high sensitivity, linearity, and capability to measure multiple elements using a single tunable laser and suggest that the development of portable W-coil LIF instrumentation using compact, solid-state lasers is feasible.

  5. Fluorescence Image Segmentation by using Digitally Reconstructed Fluorescence Images

    Blumer, Clemens; Vivien, Cyprien; Oertner, Thomas G; Vetter, Thomas

    2011-01-01

    In biological experiments fluorescence imaging is used to image living and stimulated neurons. But the analysis of fluorescence images is a difficult task. It is not possible to conclude the shape of an object from fluorescence images alone. Therefore, it is not feasible to get good manual segmented nor ground truth data from fluorescence images. Supervised learning approaches are not possible without training data. To overcome this issues we propose to synthesize fluorescence images and call...

  6. Sedimentation separation and fluorescent X-ray analysis of very small amount of cobalt in pure iron

    Kato, Kensaku

    1990-01-01

    As the simple method of separation and analysis of very small amount of cobalt up to 1 ppm in pure iron, the application of sedimentation separation and fluorescent X-ray analysis was examined. By adding citric acid to the sample solution, the masking of the main components was carried out, and cobalt was deposited with 2-nitroso 1-naphtol separated and concentrated on a membrane filter. The reagents and equipments used are shown. The operation of the fundamental quantitative determination was determined. The condition of measurement, the condition of sedimentation separation, the effect of coexisting elements, the rate of recovery of cobalt, the calibration curve, and the analysis of actual samples are reported. By separating and concentrating cobalt on a membrane filter, this method eliminates the obstruction of coexisting elements to the object element, which is the problem in fluorescent X-ray measurement, and has the merit of simple operation and wide range of quantitative determination. (K.I.)

  7. Initial idea to use optical flats for x-ray fluorescence analysis and recent applications to diffraction studies

    Horiuchi, T.

    1993-01-01

    Described in this work is the initial idea of using an optical flat for X-ray fluorescence analysis based upon studies of anomalous surface reflection (ASR). To develop total-reflection X-ray fluorescence analysis (TXRF) as one of the most powerful tools for microchemical analysis, various experiments such as the micro-determinations of uranium in sea-water, iron in human blood and rare earth elements in hot spring-water were attempted. Furthermore, the physically interesting experiment on Compton scattering under total-reflection conditions was conducted. Recent applications of the total-reflection phenomenon to diffraction studies, i.e. total-reflection X-ray diffraction (TXRD), are also presented. (author)

  8. QUANTITATIVE IMAGING AND STATISTICAL ANALYSIS OF FLUORESCENCE IN SITU HYBRIDIZATION (FISH) OF AUREOBASIDIUM PULLULANS. (R823845)

    AbstractImage and multifactorial statistical analyses were used to evaluate the intensity of fluorescence signal from cells of three strains of A. pullulans and one strain of Rhodosporidium toruloides, as an outgroup, hybridized with either a universal o...

  9. Automated Image Analysis for Quantitative Fluorescence In Situ Hybridization with Environmental Samples▿ †

    Zhou, Zhi; Pons, Marie Noëlle; Raskin, Lutgarde; Zilles, Julie L.

    2007-01-01

    When fluorescence in situ hybridization (FISH) analyses are performed with complex environmental samples, difficulties related to the presence of microbial cell aggregates and nonuniform background fluorescence are often encountered. The objective of this study was to develop a robust and automated quantitative FISH method for complex environmental samples, such as manure and soil. The method and duration of sample dispersion were optimized to reduce the interference of cell aggregates. An au...

  10. Diversity and evolution of coral fluorescent proteins.

    Naila O Alieva

    2008-07-01

    Full Text Available GFP-like fluorescent proteins (FPs are the key color determinants in reef-building corals (class Anthozoa, order Scleractinia and are of considerable interest as potential genetically encoded fluorescent labels. Here we report 40 additional members of the GFP family from corals. There are three major paralogous lineages of coral FPs. One of them is retained in all sampled coral families and is responsible for the non-fluorescent purple-blue color, while each of the other two evolved a full complement of typical coral fluorescent colors (cyan, green, and red and underwent sorting between coral groups. Among the newly cloned proteins are a "chromo-red" color type from Echinopora forskaliana (family Faviidae and pink chromoprotein from Stylophora pistillata (Pocilloporidae, both evolving independently from the rest of coral chromoproteins. There are several cyan FPs that possess a novel kind of excitation spectrum indicating a neutral chromophore ground state, for which the residue E167 is responsible (numeration according to GFP from A. victoria. The chromoprotein from Acropora millepora is an unusual blue instead of purple, which is due to two mutations: S64C and S183T. We applied a novel probabilistic sampling approach to recreate the common ancestor of all coral FPs as well as the more derived common ancestor of three main fluorescent colors of the Faviina suborder. Both proteins were green such as found elsewhere outside class Anthozoa. Interestingly, a substantial fraction of the all-coral ancestral protein had a chromohore apparently locked in a non-fluorescent neutral state, which may reflect the transitional stage that enabled rapid color diversification early in the history of coral FPs. Our results highlight the extent of convergent or parallel evolution of the color diversity in corals, provide the foundation for experimental studies of evolutionary processes that led to color diversification, and enable a comparative analysis of

  11. LED-FISH: Fluorescence microscopy based on light emitting diodes for the molecular analysis of Her-2/neu oncogene amplification

    Vollmer Ekkehard

    2008-12-01

    Full Text Available Abstract Light emitting diodes (LED, which are available as small monochromatic light sources with characteristic features such as maximum illumination power combined with minimum energy consumption and extremely long lifespan have already proved as a highly potential low-cost alternative for specific diagnostic applications in clinical medicine such as tuberculosis fluorescence microscopy. Likewise, the most reliable evaluation of Her-2/neu (c-erbB2 gene amplification, which has been established in the last few years for routine diagnosis in clinical pathology as determinant towards Herceptin-based treatment of patients with breast cancer, is based on fluorescence in situ hybridization (FISH and corresponding high priced fluorescence equipment. In order to test the possibility to utilize the advantages of low-cost LED technology on FISH analysis of c-erbB2 gene expression for routine diagnostic purposes, the applicability of a standard bright field Carl Zeiss Axiostar Plus microscope equipped with a Fraen AFTER* LED Fluorescence Microscope Kit for the detection of Her-2/neu gene signals was compared to an advanced Nikon Eclipse 80i fluorescence microscope in combination with a conventional 100W mercury vapor lamp. Both microscopes were fitted with the same Quicam FAST CCD digital camera to unequivocally compare the quality of the captured images. C-erbB2 gene expression was analyzed in 30 different human tissue samples of primary invasive breast cancer, following formalin fixation and subsequent paraffin-embedding. The Her2/neu gene signals (green were identifiable in the tumor cells in all cases and images of equal quality were captured under almost identical conditions by 480 nm (blue LED module equipped standard Axiostar microscope as compared to conventional fluorescence microscopy. In this first attempt, these monochromatic LED elements proved in principle to be suitable for the detection of Her-2/neu gene expression by FISH. Thus, our own

  12. In vivo elemental analysis in occupational medicine using X-ray fluorescence

    Christoffersson, J.O.

    1986-01-01

    A technique for the in vivo determination of cadmium in the kidney cortex using X-ray fluorescence analysis (XRF) has been developed for clinical use. The method uses the Cd K-alfa X-rays. The radiation from the tube was polarized by scattering at 90 degrees in a plastic disc. Using a Si(Li) detector the minimum detectable concentration (MDC) of cadmium in the renal cortex was about 6 ppm for an effective dose equivalent of 3 micro-Sievert. The precision of the method was estimated to be about 23 percent. The clinical usefulness was confirmed by studying 20 occupationally exposed cadmium workers and three controls. The cadmium workers showed levels of cadmium in the kidney in the range 47-317 ppm, and controls showed levels below 30 ppm. Using XRF in vivo large-scale measurements of lead in the fingerbone of more than 100 lead workers were performed. The technique used included two 57-Co sources for excitation and a higher-purity Ge detector for the analysis of the Pb K-alfa X-rays. The MDC was about 20 ppm for an effective dose equivalent of 0.1 micro-Sievert. The precision of the method was estimated to be about 15 per cent. The in vivo measurements showed levels of fingerbone-Pb up to 148 ppm. The existence of a significant endogenous exposure from lead in the skeleton was confirmed. The fingerbone-Pb was correlated to time-integrated blood-Pb indicating that it could be used as a rough estimated of time-integrated exposure. The results from the measurements were used to develop a three-compartment (cortical bone, trabecular bone, blood/soft tissues) model. Using this model, lead levels in fingerbone, vertebrae and blood could be predicted in good agreement with observations. (author)

  13. Neutron activation analysis technique and X-ray fluorescence in bovine liver sample

    Maihara, V.A.; Favaro, D.I.T.; Vasconcellos, M.B.A.; Sato, I.M.; Salvador, V.L.

    2002-01-01

    Many analytical techniques have been used in food and diet analysis in order to determine a great number of nutritional elements, ranging from percentage to ng g -1 , with high sensitivity and accuracy. Instrumental Neutron activation Analysis (INAA) has been employed to certificate many trace elements in biological reference materials. More recently, the X-Ray Fluorescence (FRX-WD) has been also used to determine some essential elements in food samples. The INAA has been applied in nutrition studies in our laboratory at IPEN since the 80 s. For the development of analytical methodologies the use of the reference materials with the same characteristics of the sample analyzed is essential. Several Brazilian laboratories do not have conditions to use these materials due their high cost.In this paper preliminary results of commercial bovine liver sample analyses obtained by INAA and WD-XRF methods are presented. This sample was prepared to be a Brazilian candidate of reference material for a group of laboratories participating in a research project sponsored by FAPESP. The concentrations of some elements like Cl, K, Na, P, S and trace elements Br, Ca, Co, Cu, Fe, Mg, Mn, Mo, Rb, Se and Zn were determined by INAA and WD-XFR. For validation methodology of both techniques, NIST SRM 1577b Bovine Liver reference material was analyzed and the detection limits were calculated. The concentrations of elements determined by both analytical techniques were compared by using the Student's t-test and for Cl, Cu, Fe, K, Mg, Na, Rn and Zn the results do show no statistical difference for 95% significance level. (author)

  14. Measurement of apoptosis by SCAN©, a system for counting and analysis of fluorescently labelled nuclei

    Neta Shlezinger

    2014-11-01

    Full Text Available Apoptosis-like programmed cell death (A-PCD is a universal process common to all types of eukaryotic organisms. Because A-PCD-associated processes are conserved, it is possible to define A-PCD by a standard set of markers. Many of the popular methods to measure A-PCD make use of fluorescent ligands that change in intensity or cellular localization during A-PCD. In single cell organisms, it is possible to quantify levels of A-PCD by scoring the number of apoptotic cells using flow cytometry instruments. In a multicellular organism, quantification of A-PCD is more problematic due to the complex nature of the tissue. The situation is further complicated in filamentous fungi, in which nuclei are divided between compartments, each containing a number of nuclei, which can also migrate between the compartments. We developed SCAN©, a System for Counting and Analysis of Nuclei, and used it to measure A-PCD according to two markers – chromatin condensation and DNA strand breaks. The package includes three modules designed for counting the number of nuclei in multi-nucleated domains, scoring the relative number of nuclei with condensed chromatin, and calculating the relative number of nuclei with DNA strand breaks. The method provides equal or better results compared with manual counting, the analysis is fast and can be applied on large data sets. While we demonstrated the utility of the software for measurement of A-PCD in fungi, the method is readily adopted for measurement of A-PCD in other types of multicellular specimens.

  15. Achieving 100% Efficient Postcolumn Hydride Generation for As Speciation Analysis by Atomic Fluorescence Spectrometry.

    Marschner, Karel; Musil, Stanislav; Dědina, Jiří

    2016-04-05

    An experimental setup consisting of a flow injection hydride generator coupled to an atomic fluorescence spectrometer was optimized in order to generate arsanes from tri- and pentavalent inorganic arsenic species (iAs(III), iAs(V)), monomethylarsonic acid (MAs(V)), and dimethylarsinic acid (DMAs(V)) with 100% efficiency with the use of only HCl and NaBH4 as the reagents. The optimal concentration of HCl was 2 mol L(-1); the optimal concentration of NaBH4 was 2.5% (m/v), and the volume of the reaction coil was 8.9 mL. To prevent excessive signal noise due to fluctuations of hydride supply to an atomizer, a new design of a gas-liquid separator was implemented. The optimized experimental setup was subsequently interfaced to HPLC and employed for speciation analysis of arsenic. Two chromatography columns were tested: (i) ion-pair chromatography and (ii) ion exchange chromatography. The latter offered much better results for human urine samples without a need for sample dilution. Due to the equal hydride generation efficiency (and thus the sensitivities) of all As species, a single species standardization by DMAs(V) standard was feasible. The limits of detection for iAs(III), iAs(V), MAs(V), and DMAs(V) were 40, 97, 57, and 55 pg mL(-1), respectively. Accuracy of the method was tested by the analysis of the standard reference material (human urine NIST 2669), and the method was also verified by the comparative analyses of human urine samples collected from five individuals with an independent reference method.

  16. Characteristics of curcumin using cyclic voltammetry, UV–vis, fluorescence and thermogravimetric analysis

    Masek, Anna; Chrzescijanska, Ewa; Zaborski, Marian

    2013-01-01

    Highlights: • Electrooxidation of curcumin was investigated with cyclic voltammetry. • The curcumin is irreversibly oxidized at the platinum electrode in anhydrous media. • Absorbance, fluorescence and thermogravimetric analysis of curcumin was studied. • The HOMO and Mapped Electron Densities were calculated using HyperChem. • Oxidation mechanism for curcumin proposed. -- Abstract: Curcumin, the yellow, primary bioactive component of turmeric, has recently received attention from chemists due its wide range of potential biological applications as an antioxidant, anti-inflammatory, and anti-carcinogenic agent. The electrochemical behaviour of curcumin at a platinum electrode has been studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The oxidation of curcumin is an irreversible process that proceeds in two steps in 0.1 M (C 4 H 9 ) 4 NClO 4 in acetonitrile. The process of oxidation and its kinetics have been investigated. The rate constant, electron transfer coefficient and diffusion coefficients for the electrochemical oxidation of curcumin were determined. A mechanism for the oxidation of curcumin is proposed. The data obtained are consistent with the current literature and suggest that voltammetric studies on mechanically transferred solids may be a convenient method for elucidating the electrochemical oxidation mechanisms of compounds in anhydrous media. Theoretical calculations regarding the optimization of curcumin, electronic properties like highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) were calculated using with HyperChem software by AM1 semi-empirical method. The properties of curcumin in a homogeneous environment were investigated using spectroscopic techniques and thermogravimetric analysis

  17. Total reflection x-ray fluorescence spectrometers for multielemental analysis: status of commercial equipment

    Ayala Jimenez, R.E.

    2000-01-01

    Multi-elemental analysis by total reflection x-ray fluorescence spectrometry has evolved during two decades. At the present there are commercial equipment available for the chemical analysis in all kind of biological and mineral samples. The electronic industry has also been benefited from the scientific and technological developments in the field of TXRF. The basic components of the spectrometers can be summarized as follow: a) excitation source; b) geometric arrangement (optics) for collimation and monochromatization of the primary radiation; c) x-ray detector; d) hardware and software for operation of the instrument, data acquisition and spectral deconvolution to determine the concentrations of the element present in the sample (quantitative analysis). As optional there are manufacturers offering the conventional 45 degrees geometry for direct excitation of bulky liquid or solid samples. Personal communications of the author and the commercial brochures available at the moment of writing this presentation have allowed to list the following type of components used in the TXRF spectrometers for multi-elemental analysis (the devices used in the electronic industry to analyze silicon wafers are excluded). Excitation: high power x-ray tube, output from 1300 to 2000 watts; metal ceramic low power-ray tube, output up to 50 watts. Different anodes are used but molybdenum, tungsten and copper are frequent. The excitation systems can be customized according to the requirements of the laboratory. Detector: Si-Li semi-conductor liquid nitrogen cooled; silicon solid state thermoelectrically cooled (silicon drift detector SDD and Si-PIN diode). Optics: multilayer monochromator of Si-W or Ni-C; double multilayer monochromator. Electronics: spectroscopy amplifier, analog to digital converter adapted to a PC compatible computer with software in Windows environment for the whole operation of the spectrometer and for qualy/quantitative analysis of samples are standards in the

  18. Time-Resolved Fluorescent Immunochromatography of Aflatoxin B1 in Soybean Sauce: A Rapid and Sensitive Quantitative Analysis.

    Wang, Du; Zhang, Zhaowei; Li, Peiwu; Zhang, Qi; Zhang, Wen

    2016-07-14

    Rapid and quantitative sensing of aflatoxin B1 with high sensitivity and specificity has drawn increased attention of studies investigating soybean sauce. A sensitive and rapid quantitative immunochromatographic sensing method was developed for the detection of aflatoxin B1 based on time-resolved fluorescence. It combines the advantages of time-resolved fluorescent sensing and immunochromatography. The dynamic range of a competitive and portable immunoassay was 0.3-10.0 µg·kg(-1), with a limit of detection (LOD) of 0.1 µg·kg(-1) and recoveries of 87.2%-114.3%, within 10 min. The results showed good correlation (R² > 0.99) between time-resolved fluorescent immunochromatographic strip test and high performance liquid chromatography (HPLC). Soybean sauce samples analyzed using time-resolved fluorescent immunochromatographic strip test revealed that 64.2% of samples contained aflatoxin B1 at levels ranging from 0.31 to 12.5 µg·kg(-1). The strip test is a rapid, sensitive, quantitative, and cost-effective on-site screening technique in food safety analysis.

  19. Improving the spectral analysis of Fluorescence Resonance Energy Transfer in live cells: application to interferon receptors and Janus kinases.

    Krause, Christopher D; Digioia, Gina; Izotova, Lara S; Pestka, Sidney

    2013-10-01

    The observed Fluorescence Resonance Energy Transfer (FRET) between fluorescently labeled proteins varies in cells. To understand how this variation affects our interpretation of how proteins interact in cells, we developed a protocol that mathematically separates donor-independent and donor-dependent excitations of acceptor, determines the electromagnetic interaction of donors and acceptors, and quantifies the efficiency of the interaction of donors and acceptors. By analyzing large populations of cells, we found that misbalanced or insufficient expression of acceptor or donor as well as their inefficient or reversible interaction influenced FRET efficiency in vivo. Use of red-shifted donors and acceptors gave spectra with less endogenous fluorescence but produced lower FRET efficiency, possibly caused by reduced quenching of red-shifted fluorophores in cells. Additionally, cryptic interactions between jellyfish FPs artefactually increased the apparent FRET efficiency. Our protocol can distinguish specific and nonspecific protein interactions even within highly constrained environments as plasma membranes. Overall, accurate FRET estimations in cells or within complex environments can be obtained by a combination of proper data analysis, study of sufficient numbers of cells, and use of properly empirically developed fluorescent proteins. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Variable selection based on clustering analysis for improvement of polyphenols prediction in green tea using synchronous fluorescence spectra

    Shan, Jiajia; Wang, Xue; Zhou, Hao; Han, Shuqing; Riza, Dimas Firmanda Al; Kondo, Naoshi

    2018-04-01

    Synchronous fluorescence spectra, combined with multivariate analysis were used to predict flavonoids content in green tea rapidly and nondestructively. This paper presented a new and efficient spectral intervals selection method called clustering based partial least square (CL-PLS), which selected informative wavelengths by combining clustering concept and partial least square (PLS) methods to improve models’ performance by synchronous fluorescence spectra. The fluorescence spectra of tea samples were obtained and k-means and kohonen-self organizing map clustering algorithms were carried out to cluster full spectra into several clusters, and sub-PLS regression model was developed on each cluster. Finally, CL-PLS models consisting of gradually selected clusters were built. Correlation coefficient (R) was used to evaluate the effect on prediction performance of PLS models. In addition, variable influence on projection partial least square (VIP-PLS), selectivity ratio partial least square (SR-PLS), interval partial least square (iPLS) models and full spectra PLS model were investigated and the results were compared. The results showed that CL-PLS presented the best result for flavonoids prediction using synchronous fluorescence spectra.

  1. Simple procedure for nutrient analysis of coffee plant with energy dispersive X-ray fluorescence spectrometry (EDXRF)

    Tezotto, Tiago; Favarin, Jose Laercio; Neto, Ana Paula; Azevedo, Ricardo Antunes, E-mail: tiago.tezotto@usp.br [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil); Gratao, Priscila Lupino [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP/ FCAV), Jaboticabal, SP (Brazil). Dept. de Biologia Aplicada a Agropecuaria; Mazzafera, Paulo [Universidade Estadual de Campinas (UNICAMP/IB), SP (Brazil). Dept. Biologia Vegetal

    2013-07-15

    Nutrient analysis is used to estimate nutrient content of crop plants to manage fertilizer application for sustained crop production. Direct solid analysis of agricultural and environmental samples by energy dispersive X-ray fluorescence spectrometry (EDXRF) was chosen as alternative technique to evaluate the simultaneous multielemental quantification of the most important essential elements in coffee (Coffea arabica L.) plants. Inductively coupled plasma atomic emission spectrometry and certified reference materials made from leaves were used to calibrate and check the trueness of EDXRF method for the determination of the concentration of several nutrients in coffee leaves and branches. Fluorescence spectrometry proved to be advantageous and presented low cost as loose powder samples could be used. Samples collected from a field experiment where coffee plants were treated with excess of Ni and Zn were used to verify the practical application of the method. Good relationships were achieved between certified values and data obtained by EDXRF, with recoveries ranging from 82 to 117 %.(author)

  2. Quantitative analysis of phosphoinositide 3-kinase (PI3K) signaling using live-cell total internal reflection fluorescence (TIRF) microscopy.

    Johnson, Heath E; Haugh, Jason M

    2013-12-02

    This unit focuses on the use of total internal reflection fluorescence (TIRF) microscopy and image analysis methods to study the dynamics of signal transduction mediated by class I phosphoinositide 3-kinases (PI3Ks) in mammalian cells. The first four protocols cover live-cell imaging experiments, image acquisition parameters, and basic image processing and segmentation. These methods are generally applicable to live-cell TIRF experiments. The remaining protocols outline more advanced image analysis methods, which were developed in our laboratory for the purpose of characterizing the spatiotemporal dynamics of PI3K signaling. These methods may be extended to analyze other cellular processes monitored using fluorescent biosensors. Copyright © 2013 John Wiley & Sons, Inc.

  3. Energy dispersive X-ray fluorescence analysis with Bragg polarized Mo radiation. Energiedispersive Roentgenfluoreszenzanalyse mit Bragg-polarisierter Mo Strahlung

    Gloeckl, H

    1983-01-01

    The aim of introducing energy dispersive analysis into X-ray fluorescence analysis is to suppress background from the Bremsstrahlung spectrum and the characteristic radiation without an undue reduction of the signal. The variant under consideration uses linearly polarization radiation obtained after a Bragg reflection,under delta = 90/sup 0/. In an introductory part, Bragg reflection, fluorescence and strong radiation are considered quantitatively with respect to counting statistics and detection limits. In the experimental part two combinations are describe, of a Ta crystal with a Cr tube and of a Mo crystal with a Mo tube. Details of adjustment, sample preparation and calibration and detection limits are given. The pros and cons of the Ta/Cr and the Mo/Mo are contrasted and proposals for further improvements are given.

  4. Relative evaluation of neutron activation, X-ray fluorescence and spark source mass spectrometry for multielement analysis of geothermal waters

    Blommaert, W.; Vandelannoote, R.; Van't Dack, L.; Gijbels, R.; Van Grieken, R.

    1980-01-01

    To sulfide geothermal waters from the French Pyrenees region and bicarbonate and chloride waters from the French Vosges area, all of the following analysis techniques were applied in order to compose a broad inventory of trace elements: (1) for the dissolved metarial: neutron activation analysis after a freeze-drying step using a very short cycle, short cycle or long cycle, neutron activation after co-crystallization on 1-(2-pyridylazo)-2-naphthol (PAN) using a short cycle or long cycle, X-ray fluorescence after co-crystallization on PAN and spark source mass spectrometry after evaporation on graphite or preconcentration on PAN, and, (2) for the filtered or suspended material: neutron activation using a very short, short or long cycle and X-ray fluorescence. Altogether, on the average some 30 elements could be determined above the detection limit in solution and 15 in suspension. (author)

  5. Subversion of complement by hematophagous parasites

    Schroeder, Hélène; Skelly, Patrick; Zipfel, Peter F.; Losson, Bertrand; Vanderplasschen, Alain

    2009-01-01

    The complement system is a crucial part of innate and adaptive immunity which exerts a significant evolutionary pressure on pathogens. It has selected for those pathogens, mainly micro-organisms but also parasites, that have evolved countermeasures. The characterization of how pathogens evade complement attack is a rapidly developing field of current research. In recent years, multiple complement evasion strategies have been characterized. In this review, we focus on complement escape mechani...

  6. conformational complexity of complement component C3

    Janssen, B.J.C.

    2007-01-01

    The complement system is an important part of the immune system and critical for the elimination of pathogens. In mammals the complement system consists of an intricate set of about 35 soluble and cell-surface plasma proteins. Central to complement is component C3, a large protein of 1,641 residues.

  7. Complement activation and inhibition: a delicate balance

    Sjöberg, A P; Trouw, L A; Blom, A M

    2009-01-01

    proteins, pentraxins, amyloid deposits, prions and DNA, all bind the complement activator C1q, but also interact with complement inhibitors C4b-binding protein and factor H. This contrasts to the interaction between C1q and immune complexes, in which case no inhibitors bind, resulting in full complement...

  8. [Determination of H2S in Rat Intestinal Perfusion Solution Based on Fluorescence Analysis].

    Hou, Jun-feng; Li, Xin-xia; Shen, Xue-ru; Huojia, Miliban; Guan, Ming

    2015-08-01

    Under alkaline conditions, Fluorescein mercury has strong fluorescence, however, when it met S(2-), its fluorescence would quench, in view of the above, a fluorescence method for determination of H2S in biological samples was established. In the 0.1 mol · L(-1) NaOH dilution, when the concentration of fluorescein Mercury and Na2S was 5.0 × 10(-5) and 1.0 × 10(-5) mol · L(-1) respectively, the fluorescence intensity of system was determined at 522 nm. The results showed that, at the range of 4.0 × 10(-7)~2.0 × 10(-6) mol · L(-1), the concentration decreasing of H2S and fluorescence intensity had good linear relationship, r=0.9980, the RSD of precision test was 4.59% (n=7), the detection limit was 3.5 × 10(-8) mol · L(-1), the content of H2S in the sample were 1.01 × 10(-6) and 1.15 × 10(-6) mol · L(-1), and the recovery rate was 95.8%~101.0%, the method has the advantages of simple operation, high sensitivity, good selectivity, can accurately determine of H2S in intestinal perfused solution, and provides the basis for the determination of endogenous H2S.

  9. Multiplexed fluorescent microarray for human salivary protein analysis using polymer microspheres and fiber-optic bundles.

    Nie, Shuai; Benito-Peña, Elena; Zhang, Huaibin; Wu, Yue; Walt, David R

    2013-10-10

    Herein, we describe a protocol for simultaneously measuring six proteins in saliva using a fiber-optic microsphere-based antibody array. The immuno-array technology employed combines the advantages of microsphere-based suspension array fabrication with the use of fluorescence microscopy. As described in the video protocol, commercially available 4.5 μm polymer microspheres were encoded into seven different types, differentiated by the concentration of two fluorescent dyes physically trapped inside the microspheres. The encoded microspheres containing surface carboxyl groups were modified with monoclonal capture antibodies through EDC/NHS coupling chemistry. To assemble the protein microarray, the different types of encoded and functionalized microspheres were mixed and randomly deposited in 4.5 μm microwells, which were chemically etched at the proximal end of a fiber-optic bundle. The fiber-optic bundle was used as both a carrier and for imaging the microspheres. Once assembled, the microarray was used to capture proteins in the saliva supernatant collected from the clinic. The detection was based on a sandwich immunoassay using a mixture of biotinylated detection antibodies for different analytes with a streptavidin-conjugated fluorescent probe, R-phycoerythrin. The microarray was imaged by fluorescence microscopy in three different channels, two for microsphere registration and one for the assay signal. The fluorescence micrographs were then decoded and analyzed using a homemade algorithm in MATLAB.

  10. Analysis of biological slurry samples by total x-ray fluorescence after in situ microwave digestion

    Lue-Meru, M.P.; Capote, T.; Greaves, E.

    2000-01-01

    Biological slurry samples were analyzed by total reflection x-ray fluorescence (TXRF) after an in situ microwave digestion procedure on the quartz reflector. This method lead to the removal of the matrix by the digestion and permits the enrichment of the analites by using sample amounts higher than those normally used in TXRF for the thin layer requirement since the organic matrix is removed. In consequence, the pre-concentration of sample is performed and the detection capability is increased by a quasi direct method. The samples analyzed were the international IAEA blood standard, the SRM bovine liver 1577-a standard and fresh onion tissues. Slurries were prepared in three ways: a.- weighing a sample amount on the reflector and adding suprapure nitric acid and internal standard followed by microwave digestion, b.-weighing a sample amount and water with an appropriate concentration of the internal standard in an Eppendorf vial, taking then an aliquot to the quartz reflector for microwave digestion with suprapure nitric acid, c.- weighing a sample amount of fresh tissue, homogenising with high speed homegenator to obtain a slurry sample which can be diluted in an ependorf vial with water an the internal standard. Then an aliquot is taken to the reflector for microwave digestion with suprapure nitric acid. Further details of sample preparation procedures will be discussed during presentation. The analysis was carried out in a Canberra spectrometer using the Kalpha lines of the Ag and Mo tubes. The elements Ca, K, Fe, Cu, Zn, Se, Mn, Rb, Br, Sr were determined. The effect of the preparation procedure was evaluated by the accuracy and precision of the results for each element and the percent of recovery. (author)

  11. X-ray Peltier cooled detectors for X-ray fluorescence analysis

    Loupilov, A.; Sokolov, A.; Gostilo, V.

    2001-01-01

    The recent results on development of X-ray Si(Li), Si-planar and CdTe p-i-n detectors cooled by Peltier coolers for fabrication of laboratory and portable XRF analysers for different applications are discussed. Low detection limits of XRF analysers are provided by increasing of detectors sensitive surface; improvement of their spectrometrical characteristics; decreasing of front-end-electronics noise level; Peltier coolers and vacuum chambers cooling modes optimization. Solution of all mentioned tasks allowed to develop Peltier cooled detectors with the following performances: (1.) Si(Li) detectors: S=20 mm 2 , thickness=3.5 mm, 175 eV (5.9 keV), 430 eV (59.6 keV); S=100 mm 2 ; thickness=4.5 mm, 270 eV (5.9 keV), 485 eV (59.6 keV). (2.) Si-planar detector: S=10 mm 2 , thickness=0.4 mm, 230 eV (5.9 keV), 460 eV (59.6 keV). (3.) CdTe p-i-n detectors: S=16 mm 2 , thickness=0.5 mm, 350 eV (5.9 keV), 585 eV (59.6 keV). S=16 mm 2 , thickness=1.2 mm, 310 eV (5.9 keV), 600 eV (59.6 keV). Advantages and disadvantages of all types of detectors for X-ray fluorescence analysis are compared. Spectra are presented. Application of different XRF analysers based on developed detectors in medicine, environmental science, industry, cryminalistics and history of art are demonstrated

  12. X-ray Peltier cooled detectors for X-ray fluorescence analysis

    Loupilov, A.; Sokolov, A.; Gostilo, V.

    2000-01-01

    The recent results on development of X-ray Si(Li), Si-planar and CdTe p-i- n detectors cooled by Peltier coolers for fabrication of laboratory and portable XRF analysers for different applications are discussed. Low detection limits of XRF analysers are provided by increasing of detectors sensitive surface; improvement of their spectrometrical characteristics; decreasing of front-end-electronics noise level; Peltier coolers and vacuum chambers cooling modes optimization. Solution of all mentioned tasks allowed to develop Peltier cooled detectors with the following performances: (1) Si(Li) detectors: S = 20 mm 2 , thickness = 3.5 mm, 175 eV (5.9 keV), 430 eV (59.6 keV); S = 100 mm 2 ; thickness = 4.5 mm, 270 eV (5.9 keV), 485 eV (59,6 keV). (2) Si-planar detector: S = 10 mm 2 , thickness = 0.4 mm, 230 eV (5.9 keV), 460 eV (59.6 keV). (3) CdTe p-i-n detectors: S = 16 mm 2 , thickness 0.5 mm, 350 eV (5.9 keV), 585 eV (59.6 keV). S = 16 mm 2 , thickness = 1.2 mm, 310 eV (5.9 keV), 600 eV (59.6 keV). Advantages and disadvantages of all types of detectors for X-ray fluorescence analysis are compared. Spectra are presented. Application of different XRF analysers based on developed detectors in medicine, environmental science, industry, criminalistics and history of art are demonstrated. (author)

  13. Analysis of agricultural soils by using energy dispersive X-ray fluorescence

    Anjos, Marcelino Jose dos

    2000-03-01

    In this work, we describe an Energy Dispersive x-ray Fluorescence System with a x-ray tube excitation for trace analysis of environmental samples (soil). The system was used to analyze the contamination of metals in treated soils with doses of 10, 20 and 30 ton/ha of compound organic of urban garbage of the type Fertilurb and 10 ton/ha of aviary bed (manure of birds). Samples of roots and foliages of plant radishes cultivated in these soils were also analyzed. The soil samples were collected in five different depths of 0,5, 5-10, 10-20, 20-40 and 40-60 cm. The experimental set-up is composed by an OXFORD X-ray (30 kV, 50 μA and W anode), an ORTEC Si-Li detector, with an energy resolution of about 180 eV at 5.9 keV and an ORTEC multichannel-analyser. The X-ray spectrum tube is quasi-monochromatic by using of Ti filter. Samples were prepared in pellet form with superficial density in the range of 100 mg/cm 2 . The fundamental parameter method was used in order to verify the elemental concentration. It was possible to determine the concentrations of thirteen elements: K, Ca, Ti, Mn, Fe, Cu, Zn, Br, Rb, Sr, Y, Zr and Pb in the treated soils with compounds organic. The results indicate that the values found for K, Ca, Rb, Sr, Zr and Pb are significantly above the upper confidence limits for the control soil (α = 0.05). There is a real different between these elements compared to their relationship in the control soils, (α=0,05). There is a real difference between these elements compared to their relationship in the control soils, confirming the influence of the organic compounds in the soil. (author)

  14. Chromosome analysis of nuclear power plant workers using fluorescence in situ hybridization and Giemsa assay

    Hristova, Rositsa; Hadjidekova, Valeria; Grigorova, Mira; Nikolova, Teodora; Bulanova, Minka; Popova, Ljubomira; Staynova, Albena; Benova, Donka

    2013-01-01

    The aim of this study was to evaluate the genotoxic effects of ionizing radiation in vivo in exposed Bulgarian nuclear power plant workers by using classical cytogenetic and molecular cytogenetic analyses of peripheral lymphocytes. Chromosome analysis using fluorescence in situ hybrydization (FISH) and Giemsa techniques was undertaken on 63 workers and 45 administrative staff controls from the Bulgarian Nuclear Power Plant. Using the Giemsa method, the frequencies of cells studied with chromosome aberrations, dicentrics plus rings and chromosome fragments in the radiation workers were significantly higher compared with the control group (P=0.044, P=0.014, and P=0.033, respectively). A significant association between frequencies of dicentrics plus rings and accumulated doses was registered (P<0.01). In the present study, a FISH cocktail of whole chromosome paints for chromosomes 1, 4 and 11 was used. A significant association between frequency of translocations and accumulated doses was also observed (P<0.001). Within the control group, a correlation was found between age and the spontaneous frequency of translocations. No correlation was found between smoking status and frequency of translocations. When compared with the control group, workers with accumulated doses up to 100 mSv showed no increase in genome translocation frequency, whereas workers with accumulated doses from 101 to 200 mSv showed a statistically significant doubling of genome translocation frequency (P=0.009). Thus, in cases of chronic exposure and for purposes of retrospective dosimetry, the genome frequency of translocations is a more useful marker for evaluation of genotoxic effects than dicentric frequency. (author)

  15. Total reflection X-ray fluorescence analysis of airborne silver nanoparticles from fabrics.

    Menzel, Magnus; Fittschen, Ursula Elisabeth Adriane

    2014-03-18

    Ag nanoparticles (NPs) are usually applied to consumer products because of their antimicrobial properties, which are desired in fabrics for sportswear as well as cloth used for cleaning. Hazards to human health from airborne Ag NPs may occur when the NPs are inhaled. NPs are comparable in size to macromolecules and viruses and able to penetrate deep into the lungs, e.g., the alveoli, where they may cause damage to cells and tissue due to their large surface area. In this study, aerosols released form fabrics treated with Ag NPs were collected using a low pressure Berner impactor and analyzed with total reflection X-ray fluorescence (TXRF). We found that the Ag NPs are released primarily in the form of larger particles, mainly 0.13-2 μm, probably attached to fiber material. Using an electron micro probe, single particles could be identified. The detection of backscattered electrons suggests small spots on the particle consist of a heavier element, which most likely is Ag, although the signal in energy-dispersive X-ray spectroscopy (EDX) was below the lower limit of detection (LOD). To achieve LODs necessary for Ag determination, Ar peaks were eliminated by a nitrogen atmosphere provided by the "Picofox-box". This enables linear calibration and quantification of Ag. The LOD was calculated at 0.2 ng (2.0 ppb). Following the TXRF and scanning electron microscopy (SEM)/EDX analysis, the aerosol samples were dissolved in nitric acid and analyzed with ICPMS to successfully confirm the results obtained by the TXRF measurements.

  16. The application of energy-dispersive X-Ray fluorescence spectrometry (EDXRF) to the analysis of ceramic glasses

    Ben Abdelwahed, Haifa; Reguigui, Nafaa; Ghdira, Lotfi; Khosrof, S.

    2005-01-01

    The measurement of energies and intensities of fluorescent X-rays emitted from a given material when atoms are bombarded with suitable projectiles like electrons, protons, α particles or photons has been successfully used for non-destructive elemental analysis in many applications, especially in the analysis of ceramic glasses. Use of radioisotopes as a source of excitation radiation in combination with high resolution semiconductor detectors in x-ray fluorescence has found wide applications in elemental analysis. A radioisotope excited X-ray fluorescence spectrometer consisting of a standard 5.45mm Si(Li) detector having a resolution of 200 eV at 5.9 keV coupled to a TRUMP-8K multichannel analyzer has been used. Tow sources of annular geometry using 10 mCi 109Cd and 10 mCi 55Fe together with PC AXIL software have been used for this study of tile-pavement glasses of ''Ksar Said'' in Tunisia. Analytical data shows that those tile pavement witch are broken in the 19th century from France (Marseille) have not the same composition of Tunisian tile pavement. Referring to our data, The kind of that analyzed glasses is of alkaline lead. we found also, through this study, the elemental compositions of different pigments (green, blue, brownish, yellow, white and red) used to color that tile-pavement glasses

  17. The application of energy-dispersive X-Ray Fluorescence spectrometry (EDXRF) to the analysis of ceramic glasses

    Ben Abdelwahed, H.; Reguigui, N.; Ghidira, L.; Khosrof, S.

    2005-01-01

    The measurement of energies and intensities of fluorescent X-rays emitted from a given material when atoms are bombarded with suitable projectiles like electrons, protons,α particles or photons have been successfully used for non destructive elemental analysis in many applications, especially in the analysis of ceramic glasses. Use of radioisotopes as a source of excitation radiation in combination with high resolution semiconductor detectors in x-ray fluorescence has found wide applications in elemental analysis. A radioisotope excited X-ray fluorescence spectrometer consisting of a standard 5.45mm Si(Li) detector having a resolution of 200 eV at 5.9 KeV coupled to a TRUMP -8K multichannel analyser has been used. Two sources of annular geometry using 10 mCi 109 CD and 10 mCi 55 Fe together with PC AXIL software have been used for this study of tile-pavement glasses of ''Ksar Said'' in Tunisia. Analytical data shows that those tile pavements which are broken in the 19th century from France (Marseille) have not the same composition of Tunisian tile pavement. Referring to our data, the kind of that analysed glasses is of alkaline lead. We found also, through this study, the elemental compositions of different pigments (green, blue, brownish, yellow, white and red) used to color those tile-pavement glasses

  18. Analysis of Indium Tin Oxide Film Using Argon Fluroide (ArF) Laser-Excited Atomic Fluorescence of Ablated Plumes.

    Ho, Sut Kam; Garcia, Dario Machado

    2017-04-01

    A two-pulse laser-excited atomic fluorescence (LEAF) technique at 193 nm wavelength was applied to the analysis of indium tin oxide (ITO) layer on polyethylene terephthalate (PET) film. Fluorescence emissions from analytes were induced from plumes generated by first laser pulse. Using this approach, non-selective LEAF can be accomplished for simultaneous multi-element analysis and it overcomes the handicap of strict requirement for laser excitation wavelength. In this study, experimental conditions including laser fluences, times for gating and time delay between pulses were optimized to reveal high sensitivity with minimal sample destruction and penetration. With weak laser fluences of 100 and 125 mJ/cm 2 for 355 and 193 nm pulses, detection limits were estimated to be 0.10% and 0.43% for Sn and In, respectively. In addition, the relation between fluorescence emissions and number of laser shots was investigated; reproducible results were obtained for Sn and In. It shows the feasibility of depth profiling by this technique. Morphologies of samples were characterized at various laser fluences and number of shots to examine the accurate penetration. Images of craters were also investigated using scanning electron microscopy (SEM). The results demonstrate the imperceptible destructiveness of film after laser shot. With such weak laser fluences and minimal destructiveness, this LEAF technique is suitable for thin-film analysis.

  19. X-RAY FLUORESCENCE ANALYSIS OF HANFORD LOW ACTIVITY WASTE SIMULANTS

    Jurgensen, A; David Missimer, D; Ronny Rutherford, R

    2006-05-08

    Savannah River National Laboratory (SRNL) was requested to develop an x-ray fluorescence (XRF) spectrometry method for elemental characterization of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) pretreated low activity waste (LAW) stream to the LAW Vitrification Plant. The WTP is evaluating the potential for using XRF as a rapid turnaround technique to support LAW product compliance and glass former batching. The overall objective of this task was to develop XRF analytical methods that provide the rapid turnaround time (<8 hours) requested by the WTP, while providing sufficient accuracy and precision to determine waste composition variations. For Phase 1a, SRNL (1) evaluated, selected, and procured an XRF instrument for WTP installation, (2) investigated three XRF sample methods for preparing the LAW sub-sample for XRF analysis, and (3) initiated scoping studies on AN-105 (Envelope A) simulant to determine the instrument's capability, limitations, and optimum operating parameters. After preliminary method development on simulants and the completion of Phase 1a activities, SRNL received approval from WTP to begin Phase 1b activities with the objective of optimizing the XRF methodology. Three XRF sample methods used for preparing the LAW sub-sample for XRF analysis were studied: direct liquid analysis, dried spot, and fused glass. The direct liquid method was selected because its major advantage is that the LAW can be analyzed directly without any sample alteration that could bias the method accuracy. It also is the fastest preparation technique--a typical XRF measurement could be completed in < 1hr after sample delivery. Except for sodium, the method detection limits (MDLs) for the most important analytes in solution, the hold point elements, were achieved by this method. The XRF detection limits are generally adequate for glass former batching and product composition reporting, but may be inadequate for some species (Hg, Cd, and Ba) important

  20. X-RAY FLUORESCENCE ANALYSIS OF HANFORD LOW ACTIVITY WASTE SIMULANTS

    Jurgensen, A; David Missimer, D; Ronny Rutherford, R

    2006-01-01

    Savannah River National Laboratory (SRNL) was requested to develop an x-ray fluorescence (XRF) spectrometry method for elemental characterization of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) pretreated low activity waste (LAW) stream to the LAW Vitrification Plant. The WTP is evaluating the potential for using XRF as a rapid turnaround technique to support LAW product compliance and glass former batching. The overall objective of this task was to develop XRF analytical methods that provide the rapid turnaround time (<8 hours) requested by the WTP, while providing sufficient accuracy and precision to determine waste composition variations. For Phase 1a, SRNL (1) evaluated, selected, and procured an XRF instrument for WTP installation, (2) investigated three XRF sample methods for preparing the LAW sub-sample for XRF analysis, and (3) initiated scoping studies on AN-105 (Envelope A) simulant to determine the instrument's capability, limitations, and optimum operating parameters. After preliminary method development on simulants and the completion of Phase 1a activities, SRNL received approval from WTP to begin Phase 1b activities with the objective of optimizing the XRF methodology. Three XRF sample methods used for preparing the LAW sub-sample for XRF analysis were studied: direct liquid analysis, dried spot, and fused glass. The direct liquid method was selected because its major advantage is that the LAW can be analyzed directly without any sample alteration that could bias the method accuracy. It also is the fastest preparation technique--a typical XRF measurement could be completed in < 1hr after sample delivery. Except for sodium, the method detection limits (MDLs) for the most important analytes in solution, the hold point elements, were achieved by this method. The XRF detection limits are generally adequate for glass former batching and product composition reporting, but may be inadequate for some species (Hg, Cd, and Ba) important to

  1. Kinetic analysis of DAF-FM activation by NO: toward calibration of a NO-sensitive fluorescent dye.

    Namin, Shabnam M; Nofallah, Sara; Joshi, Mahesh S; Kavallieratos, Konstantinos; Tsoukias, Nikolaos M

    2013-01-15

    Nitric oxide (NO) research in biomedicine has been hampered by the absence of a method that will allow quantitative measurement of NO in biological tissues with high sensitivity and selectivity, and with adequate spatial and temporal resolution. 4-amino-5-methylamino-2',7'-difluorofluorescein (DAF-FM) is a NO sensitive fluorescence probe that has been used widely for qualitative assessment of cellular NO production. However, calibration of the fluorescent signal and quantification of NO concentration in cells and tissues using fluorescent probes, have provided significant challenge. In this study we utilize a combination of mathematical modeling and experimentation to elucidate the kinetics of NO/DAF-FM reaction in solution. Modeling and experiments suggest that the slope of fluorescent intensity (FI) can be related to NO concentration according to the equation: ddtFI=2αk(1)NO(2)O(2)DAF-FMkNO+DAF-FM where α is a proportionality coefficient that relates FI to unit concentration of activated DAF-FM, k(1) is the NO oxidation rate constant, and k was estimated to be 4.3±0.6. The FI slope exhibits saturation kinetics with DAF-FM concentration. Interestingly, the effective half-maximum constant (EC(50)) increases proportionally to NO concentration. This result is not in agreement with the proposition that N(2)O(3) is the NO oxidation byproduct that activates DAF-FM. Kinetic analysis suggests that the reactive intermediate should exhibit NO-dependent consumption and thus NO(2)() is a more likely candidate. The derived rate law can be used for the calibration of DAF-FM fluorescence and the quantification of NO concentration in biological tissues. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Analysis of chemical equilibrium of silicon-substituted fluorescein and its application to develop a scaffold for red fluorescent probes.

    Hirabayashi, Kazuhisa; Hanaoka, Kenjiro; Takayanagi, Toshio; Toki, Yuko; Egawa, Takahiro; Kamiya, Mako; Komatsu, Toru; Ueno, Tasuku; Terai, Takuya; Yoshida, Kengo; Uchiyama, Masanobu; Nagano, Tetsuo; Urano, Yasuteru

    2015-09-01

    Fluorescein is a representative green fluorophore that has been widely used as a scaffold of practically useful green fluorescent probes. Here, we report synthesis and characterization of a silicon-substituted fluorescein, i.e., 2-COOH TokyoMagenta (2-COOH TM), which is a fluorescein analogue in which the O atom at the 10' position of the xanthene moiety of fluorescein is replaced with a Si atom. This fluorescein analogue forms a spirolactone ring via intramolecular nucleophilic attack of the carboxylic group in a pH-dependent manner. Consequently, 2-COOH TM exhibits characteristic large pH-dependent absorption and fluorescence spectral changes: (1) 2-COOH TM is colorless at acidic pH, whereas fluorescein retains observable absorption and fluorescence even at acidic pH, and the absorption maximum is also shifted; (2) the absorption spectral change occurs above pH 7.0 for 2-COOH TM and below pH 7.0 for fluorescein; (3) 2-COOH TM shows a much sharper pH response than fluorescein because of its pKa inversion, i.e., pKa1 > pKa2. These features are also different from those of a compound without the carboxylic group, 2-Me TokyoMagenta (2-Me TM). Analysis of the chemical equilibrium between pH 3.0 and 11.0 disclosed that 2-COOH TM favors the colorless and nonfluorescent lactone form, compared with fluorescein. Substitution of Cl atoms at the 4' and 5' positions of the xanthene moiety of 2-COOH TM to obtain 2-COOH DCTM shifted the equilibrium so that the new derivative exists predominantly in the strongly fluorescent open form at physiological pH (pH 7.4). To demonstrate the practical utility of 2-COOH DCTM as a novel scaffold for red fluorescent probes, we employed it to develop a probe for β-galactosidase.

  3. Synthesis and live-cell imaging of fluorescent sterols for analysis of intracellular cholesterol transport

    Modzel, Maciej; Lund, Frederik W.; Wüstner, Daniel

    2017-01-01

    Cellular cholesterol homeostasis relies on precise control of the sterol content of organelle membranes. Obtaining insight into cholesterol trafficking pathways and kinetics by live-cell imaging relies on two conditions. First, one needs to develop suitable analogs that resemble cholesterol...... as closely as possible with respect to their biophysical and biochemical properties. Second, the cholesterol analogs should have good fluorescence properties. This interferes, however, often with the first requirement, such that the imaging instrumentation must be optimized to collect photons from suboptimal...... fluorophores, but good cholesterol mimics, such as the intrinsically fluorescent sterols, cholestatrienol (CTL) or dehydroergosterol (DHE). CTL differs from cholesterol only in having two additional double bonds in the ring system, which is why it is slightly fluorescent in the ultraviolet (UV). In the first...

  4. Recent results of synchrotron radiation induced total reflection X-ray fluorescence analysis at HASYLAB, beamline L

    Streli, C. [Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna (Austria)]. E-mail: streli@ati.ac.at; Pepponi, G. [ITC-irst, Povo (Italy); Wobrauschek, P. [Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna (Austria); Jokubonis, C. [Atominstitut, Vienna University of Technology, Stadionallee 2, A-1020 Vienna (Austria); Falkenberg, G. [Hamburger Synchrotronstrahlungslabor at Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, D-22603 Hamburg (Germany); Zaray, G. [Institute of Inorganic and Applied Chemistry, 3 EOTVOS Univ, Budapest (Hungary); Broekaert, J. [Institute of Anorganic and Applied Chemistry, University Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany); Fittschen, U. [Institute of Anorganic and Applied Chemistry, University Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany); Peschel, B. [Institute of Anorganic and Applied Chemistry, University Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg (Germany)

    2006-11-15

    At the Hamburger Synchrotronstrahlungslabor (HASYLAB), Beamline L, a vacuum chamber for synchrotron radiation-induced total reflection X-ray fluorescence analysis, is now available which can easily be installed using the adjustment components for microanalysis present at this beamline. The detector is now in the final version of a Vortex silicon drift detector with 50-mm{sup 2} active area from Radiant Detector Technologies. With the Ni/C multilayer monochromator set to 17 keV extrapolated detection limits of 8 fg were obtained using the 50-mm{sup 2} silicon drift detector with 1000 s live time on a sample containing 100 pg of Ni. Various applications are presented, especially of samples which are available in very small amounts: As synchrotron radiation-induced total reflection X-ray fluorescence analysis is much more sensitive than tube-excited total reflection X-ray fluorescence analysis, the sampling time of aerosol samples can be diminished, resulting in a more precise time resolution of atmospheric events. Aerosols, directly sampled on Si reflectors in an impactor were investigated. A further application was the determination of contamination elements in a slurry of high-purity Al{sub 2}O{sub 3}. No digestion is required; the sample is pipetted and dried before analysis. A comparison with laboratory total reflection X-ray fluorescence analysis showed the higher sensitivity of synchrotron radiation-induced total reflection X-ray fluorescence analysis, more contamination elements could be detected. Using the Si-111 crystal monochromator also available at beamline L, XANES measurements to determine the chemical state were performed. This is only possible with lower sensitivity as the flux transmitted by the crystal monochromator is about a factor of 100 lower than that transmitted by the multilayer monochromator. Preliminary results of X-ray absorption near-edge structure measurements for As in xylem sap from cucumber plants fed with As(III) and As(V) are

  5. Recent results of synchrotron radiation induced total reflection X-ray fluorescence analysis at HASYLAB, beamline L

    Streli, C.; Pepponi, G.; Wobrauschek, P.; Jokubonis, C.; Falkenberg, G.; Zaray, G.; Broekaert, J.; Fittschen, U.; Peschel, B.

    2006-01-01

    At the Hamburger Synchrotronstrahlungslabor (HASYLAB), Beamline L, a vacuum chamber for synchrotron radiation-induced total reflection X-ray fluorescence analysis, is now available which can easily be installed using the adjustment components for microanalysis present at this beamline. The detector is now in the final version of a Vortex silicon drift detector with 50-mm 2 active area from Radiant Detector Technologies. With the Ni/C multilayer monochromator set to 17 keV extrapolated detection limits of 8 fg were obtained using the 50-mm 2 silicon drift detector with 1000 s live time on a sample containing 100 pg of Ni. Various applications are presented, especially of samples which are available in very small amounts: As synchrotron radiation-induced total reflection X-ray fluorescence analysis is much more sensitive than tube-excited total reflection X-ray fluorescence analysis, the sampling time of aerosol samples can be diminished, resulting in a more precise time resolution of atmospheric events. Aerosols, directly sampled on Si reflectors in an impactor were investigated. A further application was the determination of contamination elements in a slurry of high-purity Al 2 O 3 . No digestion is required; the sample is pipetted and dried before analysis. A comparison with laboratory total reflection X-ray fluorescence analysis showed the higher sensitivity of synchrotron radiation-induced total reflection X-ray fluorescence analysis, more contamination elements could be detected. Using the Si-111 crystal monochromator also available at beamline L, XANES measurements to determine the chemical state were performed. This is only possible with lower sensitivity as the flux transmitted by the crystal monochromator is about a factor of 100 lower than that transmitted by the multilayer monochromator. Preliminary results of X-ray absorption near-edge structure measurements for As in xylem sap from cucumber plants fed with As(III) and As(V) are reported. Detection

  6. X-ray fluorescence analysis of praseodymium oxide/oxalate for rare earth impurities

    Chandola, L.C.; Mohile, A.N.

    1976-01-01

    A method for the determination of lanthanum, cerium, neodymium and samarium oxides in praseodymium oxide is described. The sample in the oxalate form is mixed with boric acid binder in the weight ratio of 1:1 and pressed into a pellet. The pellet is irradiated by X-rays from a tungsten tube and fluorescent X-rays are dispersed by a LiF (200) crystal in a Philips semiautomatic X-ray fluorescence spectrometer. The intensity of the characteristic X-rays of the impurity elements is measured by a flow proportional counter at selected 20 angles. The minium determination limit is 0.01% for all impurities. (author)

  7. X-ray fluorescence analysis of bimetallic complexes on the basis of tantalocene trihydride

    Shurupova, T.I.; Sokolova, T.A.

    1989-01-01

    Methods of X-ray fluorescence determination of metals in tantalocene trihydride complexes of Cp 2 TaH 3 ·nMeHalm composition where Me=Cu, Mg, Hal=Cl, I, n=1 or 2, m=1 or 2 are developed. To obtain the form, stable in relation to the air oxygen and water vapours, the complexes were burut off up to metal oxides. Possibility of direct X-ray fluorescent determination is tested taking the most stable iodide copper-containing complex as an example

  8. Theoretical analysis of fluorescence signals in filamentation of femtosecond laser pulses in nitrogen molecular gas

    Arevalo, E.; Becker, A.

    2005-01-01

    We study numerically and analytically the role of the combined effect of self-focusing, geometrical focusing, and the plasma defocusing in the formation of the fluorescence signal during the filamentation of a Ti:sapphire laser pulse in nitrogen molecular gas. Results of numerical simulations are used to estimate the number of excited ions in the focal volume, which is proportional to the fluorescence signal. We find good agreement between the theoretical results and the experimental data, showing that such data can be used to get further insight into the effective focal volume during filamentation of femtosecond laser pulses in transparent media

  9. Analysis of selected elements in tobacco by wavelength dispersive X-ray fluorescence spectrometry

    Martin, J.M.

    1988-01-01

    A rapid method for the determination of 16 elements in tobacco by wavelength dispersive X-ray fluorescence spectrometry has been developed. The method is accurate and precise, and requires only 9 min per sample for quantitation. Sample preparation consists of placing a portion of dried, ground tobacco in a sample cup, and pressing at 25 tons pressure to make a compressed pellet. This pellet is then automatically analyzed by X-ray fluorescence for 16 elements. The results are stored on a computer disk for future recall and report generation. The elements are: Al, Br, Ca, Cl, Cu, Fe, K, Mg, Mn, Na, P, S, Si, Sr, Ti and Zn

  10. Applicability of multisyringe chromatography coupled to cold-vapor atomic fluorescence spectrometry for mercury speciation analysis

    Guzman-Mar, J.L.; Hinojosa-Reyes, L. [Department of Chemistry Sciences, Universidad Autonoma de Nuevo Leon, Cd. Universitaria, Pedro de Alba s/n, C.P. 66451 San Nicolas de los Garza, Nuevo Leon (Mexico); Serra, A.M. [Department of Chemistry, University of the Balearic Islands, E-07122 Palma de Mallorca (Spain); Hernandez-Ramirez, A. [Department of Chemistry Sciences, Universidad Autonoma de Nuevo Leon, Cd. Universitaria, Pedro de Alba s/n, C.P. 66451 San Nicolas de los Garza, Nuevo Leon (Mexico); Cerda, V., E-mail: victor.cerda@uib.es [Department of Chemistry, University of the Balearic Islands, E-07122 Palma de Mallorca (Spain)

    2011-12-05

    Graphical abstract: An automatic system, based on the applicability of multisyringe chromatography (MSC) coupled to cold-vapor atomic fluorescence spectrometry (CV/AFS) detection is developed for mercury speciation. Highlights: Black-Right-Pointing-Pointer The on-line coupling of MSC to CV/AFS was developed for mercury speciation analysis. Black-Right-Pointing-Pointer The speciation of MeHg{sup +}, Hg{sup 2+} and EtHg{sup +} was achieved on a RP C18 monolithic column. Black-Right-Pointing-Pointer The hyphenated system provided higher sample throughput compared to HPLC-CV/AFS. Black-Right-Pointing-Pointer The limits of detection for mercury species were comparable or better than those reported by HPLC-CV/AFS. Black-Right-Pointing-Pointer The developed method also provided low instrumental and operational costs. - Abstract: In this paper, a novel automatic approach for the speciation of inorganic mercury (Hg{sup 2+}), methylmercury (MeHg{sup +}) and ethylmercury (EtHg{sup +}) using multisyringe chromatography (MSC) coupled to cold-vapor atomic fluorescence spectrometry (CV/AFS) was developed. For the first time, the separation of mercury species was accomplished on a RP C18 monolithic column using a multi-isocratic elution program. The elution protocol involved the use of 0.005% 2-mercapthoethanol in 240 mM ammonium acetate (pH 6)-acetonitrile (99:1, v/v), followed by 0.005% 2-mercapthoethanol in 240 mM ammonium acetate (pH 6)-acetonitrile (90:10, v/v). The eluted mercury species were then oxidized under post-column UV radiation and reduced using tin(II) chloride in an acidic medium. Subsequently, the generated mercury metal were separated from the reaction mixture and further atomized in the flame atomizer and detected by AFS. Under the optimized experimental conditions, the limits of detection (3{sigma}) were found to be 0.03, 0.11 and 0.09 {mu}g L{sup -1} for MeHg{sup +}, Hg{sup 2+} and EtHg{sup +}, respectively. The relative standard deviation (RSD, n = 6) of the

  11. Application of factor analysis to chemically analyzed data in environmental samples after x-ray fluorescence analysis

    El-Sayed, A.A.

    2005-01-01

    The underlying principle of factorial analysis is frequency distribution and description of reaction in between and through the element series in specific environmental samples. Application of this factor analysis was elaborated to interpret the variance and covariance of certain elements Si, Al, Ca. K, Fe, Ti and Mg in three different types of common materials in environmental sediments, soil, and rock. These evaluations were proceeded after x-ray fluorescence measurements. Results of applications of factorial statistical data analysis show that three factors cause relationship between the above elements in a certain type of environmental samples are mainly recognized. In such cases, these factors represent the main reason for findings and interpret all hidden relationship between the chemical analyzed data. Factor one, the effect of weathering type alteration and oxidation reaction processes as a main one in case of soil and rock where they are characterized by the close covariance of a group of metals, like iron and manganese, commonly derived from weathered and altered igneous rocks. Factor two and three represents other processes. In case of soil, formation of alumino-silicate is revealed in factor two due to the positive covariance of these elements and also the presence of aluminum oxide, titanium oxide and silicon dioxide together is explained by these positive values. The inverse relation between Ca, K, Fe and Mg while indicate the presence of mineral salts which may be due to fertilization and water of irrigation. In case of factor three in that soil, it is the weakest factor that can be used to explain the relationship between the above elements

  12. Potential actionable targets in appendiceal cancer detected by immunohistochemistry, fluorescent in situ hybridization, and mutational analysis

    Millis, Sherri Z.; Kimbrough, Jeffery; Doll, Nancy; Von Hoff, Daniel; Ramanathan, Ramesh K.

    2017-01-01

    Background Appendiceal cancers are rare and consist of carcinoid, mucocele, pseudomyxoma peritonei (PMP), goblet cell carcinoma, lymphoma, and adenocarcinoma histologies. Current treatment involves surgical resection or debulking, but no standard exists for adjuvant chemotherapy or treatment for metastatic disease. Methods Samples were identified from approximately 60,000 global tumors analyzed at a referral molecular profiling CLIA-certified laboratory. A total of 588 samples with appendix primary tumor sites were identified (male/female ratio of 2:3; mean age =55). Sixty-two percent of samples were adenocarcinomas (used for analysis); the rest consisted of 9% goblet cell, 15% mucinous; 6% pseudomyxoma, and less than 5% carcinoids and 2% neuroendocrine. Tests included sequencing [Sanger, next generation sequencing (NGS)], protein expression/immunohistochemistry (IHC), and gene amplification [fluorescent in situ hybridization (FISH) or CISH]. Results Profiling across all appendiceal cancer histological subtypes for IHC revealed: 97% BRCP, 81% MRP1, 81% COX-2, 71% MGMT, 56% TOPO1, 5% PTEN, 52% EGFR, 40% ERCC1, 38% SPARC, 35% PDGFR, 35% TOPO2A, 25% RRM1, 21% TS, 16% cKIT, and 12% for TLE3. NGS revealed mutations in the following genes: 50.4% KRAS, 21.9% P53, 17.6% GNAS, 16.5% SMAD4, 10% APC, 7.5% ATM, 5.5% PIK3CA, 5.0% FBXW7, and 1.8% BRAF. Conclusions Appendiceal cancers show considerable heterogeneity with high levels of drug resistance proteins (BCRP and MRP1), which highlight the difficulty in treating these tumors and suggest an individualized approach to treatment. The incidence of low TS (79%) could be used as a backbone of therapy (using inhibitors such as 5FU/capecitabine or newer agents). Therapeutic options includeTOPO1 inhibitors (irinotecan/topotecan), EGFR inhibitors (erlotinib, cetuximab), PDGFR antagonists (regorafenib, axitinib), MGMT (temozolomide). Clinical trials targeting pathways involving KRAS, p53, GNAS, SMAD4, APC, ATM, PIK3CA, FBXW7, and

  13. Enhanced Measurements of Chromophoric Dissolved Organic Matter (CDOM) for Water Quality Analysis using a New Simultaneous Absorbance and Fluorescence Instrument

    Gilmore, A. M.

    2009-12-01

    Water quality, with respect to suspended particles and dissolved organic and inorganic compounds, is now recognized as one of the top global environmental concerns. Contemporary research indicates fluorescence spectral analyses coupled with UV-VIS absorbance assays have the potential, especially when combined and coordinated, to facilitate rapid, robust quantification of a wide range of compounds, including interactions among them. Fluorescence excitation-emission matrices (EEMs) collected over the UV-VIS region provide a wealth of information on chromophoric dissolved organic matter (CDOM). CDOM includes humic and fulvic acid, chlorophyll, petroleum, protein, amino acid, quinone, fertilizer, pesticide, sewage and numerous other compound classes. Analysis of the EEMs using conventional and multivariate techniques, including primarily parallel factor analysis (PARAFAC), provides information about many types of CDOM relevant to carbon cycling and pollution of fresh, marine and drinking water sources. Of critical concern also are the CDOM interactions with, and optical activities of, dissolved inorganic compounds. Many of the inorganic compounds and oxygen demand parameters can be analyzed with a wide range of UV-VIS absorbance assays. The instrument is designed and optimized for high UV throughput and low stray light performance. The sampling optics are optimized for both fluorescence and absorbance detection with the same sample. Both EEM and absorbance measurements implement NIST traceable instrument correction and calibration routines. The fluorescence detection utilizes a high dynamic range CCD coupled to a high-resolution spectrograph while absorbance utilizes diode based detection with a high dynamic range and extremely low-stray light specifications. The CDOM analysis is facilitated by a transfer of the data and model information with the PARAFAC routine. The EEM analysis software package facilitates coordinated correction of and correlation with the

  14. Atomic-fluorescence spectrophotometry

    Bakhturova, N.F.; Yudelevich, I.G.

    1975-01-01

    Atomic-fluorescence spectrophotometry, a comparatively new method for the analysis of trace quantities, has developed rapidly in the past ten years. Theoretical and experimental studies by many workers have shown that atomic-fluorescence spectrophotometry (AFS) is capable of achieving a better limit than atomic absorption for a large number of elements. The present review examines briefly the principles of atomic-fluorescence spectrophotometry and the types of fluorescent transition. The excitation sources, flame and nonflame atomizers, used in AFS are described. The limits of detection achieved up to the present, using flame and nonflame methods of atomization are given

  15. Complement Activation in Inflammatory Skin Diseases

    Jenny Giang

    2018-04-01

    Full Text Available The complement system is a fundamental part of the innate immune system, playing a crucial role in host defense against various pathogens, such as bacteria, viruses, and fungi. Activation of complement results in production of several molecules mediating chemotaxis, opsonization, and mast cell degranulation, which can contribute to the elimination of pathogenic organisms and inflammation. Furthermore, the complement system also has regulating properties in inflammatory and immune responses. Complement activity in diseases is rather complex and may involve both aberrant expression of complement and genetic deficiencies of complement components or regulators. The skin represents an active immune organ with complex interactions between cellular components and various mediators. Complement involvement has been associated with several skin diseases, such as psoriasis, lupus erythematosus, cutaneous vasculitis, urticaria, and bullous dermatoses. Several triggers including auto-antibodies and micro-organisms can activate complement, while on the other hand complement deficiencies can contribute to impaired immune complex clearance, leading to disease. This review provides an overview of the role of complement in inflammatory skin diseases and discusses complement factors as potential new targets for therapeutic intervention.

  16. Optimization of a polarized source for in vivo x-ray fluorescence analysis of platinum and other heavy metals

    Lewis, D.G.

    1994-01-01

    The Monte Carlo method was used to optimize a polarized photon source for the x-ray fluorescence analysis of platinum and other heavy metals in vivo. The source consisted of a 140 kVp, 25 mA x-ray tube with the photons plane-polarized by 90 o scattering. The use of plane-polarized photons results in a significant reduction in background when the fluorescent radiation is measured along the direction of polarization. A Monte Carlo computer programme was written to simulate the production and interaction of polarized photons in order to determine the optimal polarizing material and dimensions, together with beam width and geometrical arrangement of source, polarizer and beam collimators. Calculated photon energy distributions are compared with experimental data to test the validity of the model. (author)

  17. 25-gauge fibered-needle for label-free fluorescence analysis of breast masses: a first in vivo study

    Toullec, Alexis; Mathieu, Marie-Christine; Benoit, Charlotte; Farcy, René; Tourasse, Christophe; Boisserie-Lacroix, Martine; Fontaine-Aupart, Marie-Pierre; Delaloge, Suzette; Balleyguier, Corinne

    2018-02-01

    Breast lesions diagnosis and characterization need additional cost-effective techniques to avoid unnecessary invasive procedures, such as core needle biopsies, in the case of benign tumors. Endogenous fluorescence is an effective method to highlight in situ metabolic and/or structural changes between cancerous and non-cancerous lesions. In this context, we developed an original set-up, consisting of a 405 nm laser diode transmitting light through a 25 Gauge (0.45 mm x 50mm) 14° sharp fibered needle to excite intranodular fluorophores around the needle tip and providing real-time labelfree fluorescence spectral analysis of lesions from 450 nm to 650 nm. The objective was to help radiologists to classify suspicious masses in vivo and in real-time within the lesion. We reported the results of spectral differences between 14 invasive lobular carcinomas and 6 intraductal papilloma enrolled in a clinical study.

  18. Correlation between Wavelength Dispersive X-ray Fluorescence (WDXRF) analysis of hardened concrete for chlorides vs. Atomic Absorption (AA) analysis in accordance with AASHTO T- 260; sampling and testing for chloride ion in concrete and concrete raw mater

    2014-04-01

    A correlation between Wavelength Dispersive X-ray Fluorescence(WDXRF) analysis of Hardened : Concrete for Chlorides and Atomic Absorption (AA) analysis (current method AASHTO T-260, procedure B) has been : found and a new method of analysis has been ...

  19. Precision evaluation of pressed pastille preparation different methods for X-ray fluorescence analysis

    Lima, Raquel Franco de Souza; Melo Junior, Germano; Sa, Jaziel Martins

    1997-01-01

    This work relates the comparison between the results obtained with the two different methods of preparing pressed pastilles from the crushed sample. In this study, the reproductivity is evaluated, aiming to define the method that furnishes a better analytic precision. These analyses were realized with a X-ray fluorescence spectrometer at the Geology Department of the Federal University of Rio Grande do Norte

  20. Analysis of River sediments from the Tigre river (Venezuela) by radioisotope excited x-ray fluorescence

    LaBrecque, J.J.; Rosales, P.A.; Schorin, H.

    1985-01-01

    This paper describes qualitative elemental scans by both energy dispersive (radioisotope excited) and conventional wavelength dispersive x-ray fluorescence of different grain size fractions of river sediments. An internal standard thin-film technique was used. The precision of Rb, Sr, Y and Zr determination for SY-3 standard reference rock and one real sample for five independently prepared samples is demonstrated

  1. Fluorescence, Absorption, and Excitation Spectra of Polycyclic Aromatic Hydrocarbons as a Tool for Quantitative Analysis

    Rivera-Figueroa, A. M.; Ramazan, K. A.; Finlayson-Pitts, B. J.

    2004-01-01

    A quantitative and qualitative study of the interplay between absorption, fluorescence, and excitation spectra of pollutants called polycyclic aromatic hydrocarbons (PAHs) is conducted. The study of five PAH displays the correlation of the above-mentioned properties along with the associated molecular changes.

  2. Confirmation of molecular formulas of metallic complexes through X-ray fluorescence quantitative analysis

    Filgueiras, C.A.L.; Marques, E.V.; Machado, R.M.

    1984-01-01

    X-ray fluorescence spectrophotometry was employed to determined the metal content in a series of five transition element complexes (Mn, Ti, Zn, V). The results confirmed the molecular formulas of these complexes, already proposed on the basis of elemental microanalysis, solution condutimetry and other analytical methods. (C.L.B.) [pt

  3. Analysis of subnanosecond fluorescence decay curves with a 5GHz real time detection system

    Cunin, B.; Heisel, F.; Knispel, G.; Miehe, J.A.; Sipp, B.

    1975-01-01

    This paper presents a detailed description and a review on the characteristics of a fast vacuum photoelectric cell associated with a high speed cathode ray tube. In addition, this system is used to measure short-lived fluorescence decay times [fr

  4. Karyotype analysis of Lilium longiflorum and Lilium rubellum by chromosome banding and fluorescence in situ hybridisation

    Lim, K.B.; Wennekes, J.; Jong, de J.H.S.G.M.; Jacobsen, E.; Tuyl, van J.M.

    2001-01-01

    Detailed karyotypes of Lilium longiflorum and L. rubellum were constructed on the basis of chromosome arm lengths, C-banding, AgNO3 staining, and PI-DAPI banding, together with fluorescence in situ hybridisation (FISH) with the 5S and 45S rDNA sequences as probes. The C-banding patterns that were

  5. Cytogenetic analysis using fluorescence in situ hybridization (FISH) to evaluate occupational exposure to carcinogens

    Šrám, Radim; Beskid, Olena; Binková, Blanka; Rössner, P.; Šmerhovský, Zdeněk

    2004-01-01

    Roč. 149, - (2004), s. 335-344 ISSN 0378-4274 R&D Projects: GA MŽP SI/340/2/00 Institutional research plan: CEZ:AV0Z5039906 Keywords : Chromosomal aberrations * Fluorescence in situ hybridization Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.571, year: 2004

  6. Implications of the fluorescence for the conformational analysis of polymeric profisentinidins and procyanidins

    Carin A. Heifer; Joo-Sang Sun; Mark A. Matties; Wayne L. Mattice; Richard W. Hemingway; Jan P. Steynberg; Lisa A. Kelly

    1995-01-01

    The common monomeric units in the polymeric procyanidins are catechin and epicatechin, which have a hydroxyl group at C(5). this hydroxyl group is absent in the profisetinidins. The fluorescence properties have been characterized for the profisentinidin monomer and dimers, and compared with previous results for the procyanidins. There is a measurable heterogeneity in...

  7. Analysis of Caffeine in Beverages Using Aspirin as a Fluorescent Chemosensor

    Smith, Jordan; Loxley, Kristen; Sheridan, Patrick; Hamilton, Todd M.

    2016-01-01

    Caffeine (1,3,7-trimethylxanthine) is an alkaloid stimulant that is popular in beverages. Fluorescence-coupled methods have been used to measure the caffeine content in coffee, tea, soft drinks, energy drinks, and cosmetics. In this experiment, we have developed a method for detecting caffeine in beverages utilizing the effect of the caffeine…

  8. Comparative analysis of toxic elements in snuff by analytical techniques of X-ray fluorescence

    Mendoza, Mario; Olivera, Paula

    2013-01-01

    Six samples of different commercial brands of cigarettes expended in the Peruvian market have been analyzed along with two IAEA certified reference material using the technique of X-ray fluorescence energy dispersive. The results obtained in the study showed the presence of toxic metals such as Cr, Mn, Fe, Cu and Zn.

  9. Applications of Liquid Chromatography with Fluorescence Detector Diodes and the Analysis of Environmental Pollutants

    Garcia, S.; Perez, R. M.

    2012-01-01

    It presents a review on the determination of major types of organic pollutants in environmental samples by HPLC with diode array or fluorescence molecular detectors. Main objective has been to make a compilation of the analytical potential of the technique based on literature and our laboratory studies on the main aspects of analytical methodology used in the determination of these compounds. (Author) 53 refs.

  10. Quantitative method to assess caries via fluorescence imaging from the perspective of autofluorescence spectral analysis

    Chen, Q G; Xu, Y; Zhu, H H; Chen, H; Lin, B

    2015-01-01

    A quantitative method to discriminate caries lesions for a fluorescence imaging system is proposed in this paper. The autofluorescence spectral investigation of 39 teeth samples classified by the International Caries Detection and Assessment System levels was performed at 405 nm excitation. The major differences in the different caries lesions focused on the relative spectral intensity range of 565–750 nm. The spectral parameter, defined as the ratio of wavebands at 565–750 nm to the whole spectral range, was calculated. The image component ratio R/(G + B) of color components was statistically computed by considering the spectral parameters (e.g. autofluorescence, optical filter, and spectral sensitivity) in our fluorescence color imaging system. Results showed that the spectral parameter and image component ratio presented a linear relation. Therefore, the image component ratio was graded as <0.66, 0.66–1.06, 1.06–1.62, and >1.62 to quantitatively classify sound, early decay, established decay, and severe decay tissues, respectively. Finally, the fluorescence images of caries were experimentally obtained, and the corresponding image component ratio distribution was compared with the classification result. A method to determine the numerical grades of caries using a fluorescence imaging system was proposed. This method can be applied to similar imaging systems. (paper)

  11. Quantitative method to assess caries via fluorescence imaging from the perspective of autofluorescence spectral analysis

    Chen, Q. G.; Zhu, H. H.; Xu, Y.; Lin, B.; Chen, H.

    2015-08-01

    A quantitative method to discriminate caries lesions for a fluorescence imaging system is proposed in this paper. The autofluorescence spectral investigation of 39 teeth samples classified by the International Caries Detection and Assessment System levels was performed at 405 nm excitation. The major differences in the different caries lesions focused on the relative spectral intensity range of 565-750 nm. The spectral parameter, defined as the ratio of wavebands at 565-750 nm to the whole spectral range, was calculated. The image component ratio R/(G + B) of color components was statistically computed by considering the spectral parameters (e.g. autofluorescence, optical filter, and spectral sensitivity) in our fluorescence color imaging system. Results showed that the spectral parameter and image component ratio presented a linear relation. Therefore, the image component ratio was graded as 1.62 to quantitatively classify sound, early decay, established decay, and severe decay tissues, respectively. Finally, the fluorescence images of caries were experimentally obtained, and the corresponding image component ratio distribution was compared with the classification result. A method to determine the numerical grades of caries using a fluorescence imaging system was proposed. This method can be applied to similar imaging systems.

  12. An Analysis of Sources of Technological Change in Efficiency Improvement of Fluorescent Lamp Systems

    Imanaka, Takeo

    In Japan, energy efficient fluorescent lamp systems which use “rare-earth phosphors” and “electronic ballasts” have shown rapid diffusion since 1990s. This report investigated sources of technological change in the efficiency improvement of fluorescent lamp systems: (i) Fluorescent lamp and luminaires have been under steady technological development for getting more energy efficient lighting and the concepts to achieve high efficiency had been found in such activities; however, it took long time until they realized and become widely used; (ii) Electronic ballasts and rare-earth phosphors add fluorescent lamp systems not only energy efficiency but also various values such as compactness, lightweight, higher output, and better color rendering properties, which have also been expected and have induced research and development (R&D) (iii) Affordable electronic ballasts are realized by the new technology “power MOSFET” which is based on IC technologies and has been developed for large markets of information and communication technologies and mobile devices; and (iv) Rare-earth phosphors became available after rare-earth industries developed for the purpose of supplying rare-earth phosphors for color television. In terms of sources of technological change, (i) corresponds to “R&D” aiming at the particular purpose i.e. energy efficiency in this case, on the other hand, (ii), (iii), and (iv) correspond to “spillovers” from activities aiming at other purposes. This case exhibits an actual example in which “spillovers” were the critical sources of technological change in energy technology.

  13. Some aspects of detectors and electronics for x-ray fluorescence analysis

    Goulding, F.S.

    1976-08-01

    Some of the less recognized and potentially important parameters of the electronics and detectors used in X-ray fluorescence spectrometers are discussed. Detector factors include window (dead-layer) effects, time-dependent background and excess background. Noise parameters of field-effect transistors and time-variant pulse shaping are also discussed

  14. Implications of the fluorescence for the conformational analysis of polymeric profisetinidins and procyanidins

    Carin A. Helfer; Joo-Sang Sun; Mark A. Matties; Wayne L. Mattice; Richard W. Hemingway; Jan P. Steynberg; Lisa A. Kelly

    1995-01-01

    The common monomeric units in the polymeric proeyanidins are catechin and epicatechin, which have a hydroxyl group at C(5). This hydroxyl group is absent in the profisetinidins. The fluorescence properties have been characterized for the profisetinidin monomer and dimers, and compared with previous results for the procyanidins. There is a measurable heterogeneity in...

  15. Determination of Fe and Zn in healing plants by radionuclide X-ray fluorescence analysis

    Harangozo, M.; Toelgyessy, J.; Tomecek, O.; Ruzicka, I.; Cejpek, K.

    1999-01-01

    Radionuclide X-ray fluorescence method was used for the determination of Fe and Zn in healing plants (Sage, Peppermint, Stinging, Common Agrimony, Milfoil, Ribwort, Tansy, White Dead-Nettle). 238 Pu exciting source and Si/Li semiconductor detector were used for the determination. (author)

  16. Micro-hole array fluorescent sensor based on AC-Dielectrophoresis (DEP) for simultaneous analysis of nano-molecules

    Kim, Hye Jin; Kang, Dong-Hoon; Lee, Eunji; Hwang, Kyo Seon; Shin, Hyun-Joon; Kim, Jinsik

    2018-02-01

    We propose a simple fluorescent bio-chip based on two types of alternative current-dielectrophoretic (AC-DEP) force, attractive (positive DEP) and repulsive (negative DEP) force, for simultaneous nano-molecules analysis. Various radius of micro-holes on the bio-chip are designed to apply the different AC-DEP forces, and the nano-molecules are concentrated inside the micro-hole arrays according to the intensity of the DEP force. The bio-chip was fabricated by Micro Electro Mechanical system (MEMS) technique, and was composed of two layers; a SiO2 layer and Ta/Pt layer were accomplished for an insulation layer and a top electrode with micro-hole arrays to apply electric fields for DEP force, respectively. Each SiO2 and Ta/Pt layers were deposited by thermal oxidation and sputtering, and micro-hole arrays were fabricated with Inductively Coupled Plasma (ICP) etching process. For generation of each positive and negative DEP at micro-holes, we applied two types of sine-wave AC voltage with different frequency range alternately. The intensity of the DEP force was controlled by the radius of the micro-hole and size of nano-molecule, and calculated with COMSOL multi-physics. Three types of nano-molecules labelled with different fluorescent dye were used and the intensity of nano-molecules was examined by the fluorescent optical analysis after applying the DEP force. By analyzing the fluorescent intensities of the nano-molecules, we verify the various nano-molecules in analyte are located successfully inside corresponding micro-holes with different radius according to their size.

  17. Determination of some main elements and traces by x-ray fluorescence analysis in silicate rocks: a comparative study of two analytical techniques

    Andrade, M.D. de.

    1977-01-01

    The determinations of silicon, magnesium, iron, potassium, calcium, titanium, manganese, barium, strontium, rubidium, zirconium and scandium in felsic and mafic rocks, by X ray fluorescence analysis are presented. (author)

  18. Fluorescence lifetime selectivity in excitation-emission matrices for qualitative analysis of a two-component system

    Millican, D.W.; McGown, L.B.

    1989-01-01

    Steady-state fluorescence excitation-emission matrices (EEMs), and phase-resolved EEMs (PREEMs) collected at modulation frequencies of 6, 18, and 30 MHz, were used for qualitative analysis of mixtures of benzo[k]fluoranthene (τ = 8 ns) and benzo[b]fluoranthene (τ = 29 ns) in ethanol. The EEMs of the individual components were extracted from mixture EEMs by means of wavelength component vector-gram (WCV) analysis. Phase resolution was found to be superior to steady-state measurements for extraction of the component spectra, for mixtures in which the intensity contributions from the two components are unequal

  19. Application of instrumental neutron activation and X-ray fluorescence analysis to the examination of objects of art

    Panczyk, E.; Ligeza, M.; Walis, L.

    1999-01-01

    In the Institute of Nuclear Chemistry and Technology in Warsaw in collaboration with the Department of Preservation and Restoration of Works of Art of the Academy of Fine Arts in Cracow and National Museum in Warsaw systematic studies using nuclear methods, particulary instrumental neutron activation analysis and X-ray fluorescence analysis, have been carried out on the panel paintings from the Krakowska- Nowosadecka School and Silesian School of the period from the XIV-XVII century, Chinese and Thai porcelains and mummies fillings of Egyptian sarcophagi. These studies will provide new data to the existing data base, will permit to compare materials used by various schools and individual artists.

  20. Application of instrumental neutron activation and X-ray fluorescence analysis to the examination of objects of art

    Panczyk, E.; Ligeza, M.; Walis, L.

    1999-01-01

    In the Institute of Nuclear Chemistry and Technology in Warsaw in collaboration with the Department of Preservation and Restoration of Works of Art of the Academy of Fine Arts in Cracow and National Museum in Warsaw systematic studies using nuclear methods, particularly instrumental neutron activation analysis and X-ray fluorescence analysis, have been carried out on the panel paintings from the Krakowska-Nowosadecka School and Silesian School of the period from the XIV-XVII century, Chinese and Thai porcelains and mummies fillings of Egyptian sarcophagi. These studies will provide new data to the existing data base, will permit to compare materials used by various schools and individual artists. (author)