A method for reducing memory errors in the isotopic analyses of uranium hexafluoride by mass spectrometry; Methode de reduction des erreurs de memoire dans les analyses isotopiques de l'hexafluorure d'uranium par spectrometrie de masse

Energy Technology Data Exchange (ETDEWEB)

Bir, R [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1961-07-01

One of the most serious causes of systematic error in isotopic analyses of uranium from UF{sub 6} is the tendency of this material to become fixed in various ways in the mass spectrometer. As a result the value indicated by the instrument is influenced by the isotopic composition of the substances previously analysed. The resulting error is called a memory error. Making use of an elementary mathematical theory, the various methods used to reduce memory errors are analysed and compared. A new method is then suggested, which reduces the memory errors to an extent where they become negligible over a wide range of {sup 235}U concentration. The method is given in full, together with examples of its application. (author) [French] Une des causes d'erreurs systematiques les plus graves dans les analyses isotopiques d'uranium a partir d'UF{sub 6} est l'aptitude de ce produit a se fixer de diverses manieres dans le spectrometre de masse. Il en resulte une influence de la composition isotopique des produits precedemment analyses sur la valeur indiquee par l'appareil. L'erreur resultante est appelee erreur de memoire. A partir d'une theorie mathematique elementaire, on analyse et on compare les differentes methodes utilisees pour reduire les erreurs de memoire. On suggere ensuite une nouvelle methode qui reduit les erreurs de memoire dans une proportion telle qu'elles deviennent negligeables dans un grand domaine de concentration en {sup 235}U. On donne le mode operatoire complet et des exemples d'application. (auteur)

Multidimensional chromatography coupled to mass spectrometry in analysing complex proteomics samples

NARCIS (Netherlands)

Horvatovich, Peter; Hoekman, Berend; Govorukhina, Natalia; Bischoff, Rainer

Multidimensional chromatography coupled to mass spectrometry (LC(n)-MS) provides more separation power and an extended measured dynamic concentration range to analyse complex proteomics samples than one dimensional liquid chromatography coupled to mass spectrometry (1D-LC-MS). This review gives an

Analyse des kérosènes et des gas oils moyens par spectrométrie de masse à moyenne résolution Analysis of Kerosenes and Middle Distillates by Medium-Resolution Mass Spectrometry

Directory of Open Access Journals (Sweden)

Castex H.

2006-11-01

Full Text Available Une méthode d'analyse par spectrométrie de masse des kérosènes et des distillats moyens dérivée de la norme ASTM D2425, a été développée. Elle utilise le même principe de calcul du carbone moyen pour déterminer le choix des matrices appropriées. Mais elle opère à moyenne résolution, effectuant ainsi le tri des différentes masses exactes d'hydrocarbures, composés soufrés et oxygénés et évitant de ce fait toute séparation préalable par chromatographie liquide (ASTM D2 549 . Les valeurs des matrices ont été modifiées en conséquence et le calcul du carbone moyen adapté à l'étude des coupes étroites et larges. A mass-spectrometry analysis method derived from the ASTM D2425 standard has been developed for kerosenes and middle distillates (185-345°C. It uses the same principle for calculating the mean carbon value to determine the appropriate matrices. But it works with medium reso-lution so as to sort out the different exact masses of hydrocarbons, sulfur and oxygenated compounds, thus avoiding any prior separation by liquid chromatography (ASTM D2549. Therefore, the matrix values have been modified, and the calculation of the mean carbon value has been adapted for analyzing narrow and wide distillation cuts.

Phosphorylation of Mycobacterium tuberculosis ParB participates in regulating the ParABS chromosome segregation system.

Science.gov (United States)

Baronian, Grégory; Ginda, Katarzyna; Berry, Laurence; Cohen-Gonsaud, Martin; Zakrzewska-Czerwińska, Jolanta; Jakimowicz, Dagmara; Molle, Virginie

2015-01-01

Here, we present for the first time that Mycobacterium tuberculosis ParB is phosphorylated by several mycobacterial Ser/Thr protein kinases in vitro. ParB and ParA are the key components of bacterial chromosome segregation apparatus. ParB is a cytosolic conserved protein that binds specifically to centromere-like DNA parS sequences and interacts with ParA, a weak ATPase required for its proper localization. Mass spectrometry identified the presence of ten phosphate groups, thus indicating that ParB is phosphorylated on eight threonines, Thr32, Thr41, Thr53, Thr110, Thr195, and Thr254, Thr300, Thr303 as well as on two serines, Ser5 and Ser239. The phosphorylation sites were further substituted either by alanine to prevent phosphorylation or aspartate to mimic constitutive phosphorylation. Electrophoretic mobility shift assays revealed a drastic inhibition of DNA-binding by ParB phosphomimetic mutant compared to wild type. In addition, bacterial two-hybrid experiments showed a loss of ParA-ParB interaction with the phosphomimetic mutant, indicating that phosphorylation is regulating the recruitment of the partitioning complex. Moreover, fluorescence microscopy experiments performed in the surrogate Mycobacterium smegmatis ΔparB strain revealed that in contrast to wild type Mtb ParB, which formed subpolar foci similar to M. smegmatis ParB, phoshomimetic Mtb ParB was delocalized. Thus, our findings highlight a novel regulatory role of the different isoforms of ParB representing a molecular switch in localization and functioning of partitioning protein in Mycobacterium tuberculosis.

Phosphorylation of Mycobacterium tuberculosis ParB participates in regulating the ParABS chromosome segregation system.

Directory of Open Access Journals (Sweden)

Grégory Baronian

Full Text Available Here, we present for the first time that Mycobacterium tuberculosis ParB is phosphorylated by several mycobacterial Ser/Thr protein kinases in vitro. ParB and ParA are the key components of bacterial chromosome segregation apparatus. ParB is a cytosolic conserved protein that binds specifically to centromere-like DNA parS sequences and interacts with ParA, a weak ATPase required for its proper localization. Mass spectrometry identified the presence of ten phosphate groups, thus indicating that ParB is phosphorylated on eight threonines, Thr32, Thr41, Thr53, Thr110, Thr195, and Thr254, Thr300, Thr303 as well as on two serines, Ser5 and Ser239. The phosphorylation sites were further substituted either by alanine to prevent phosphorylation or aspartate to mimic constitutive phosphorylation. Electrophoretic mobility shift assays revealed a drastic inhibition of DNA-binding by ParB phosphomimetic mutant compared to wild type. In addition, bacterial two-hybrid experiments showed a loss of ParA-ParB interaction with the phosphomimetic mutant, indicating that phosphorylation is regulating the recruitment of the partitioning complex. Moreover, fluorescence microscopy experiments performed in the surrogate Mycobacterium smegmatis ΔparB strain revealed that in contrast to wild type Mtb ParB, which formed subpolar foci similar to M. smegmatis ParB, phoshomimetic Mtb ParB was delocalized. Thus, our findings highlight a novel regulatory role of the different isoforms of ParB representing a molecular switch in localization and functioning of partitioning protein in Mycobacterium tuberculosis.

Theory and technique of spark source mass spectrometry; Theorie et technique de la spectrometrie de masse a etincelles

Energy Technology Data Exchange (ETDEWEB)

Stefani, R [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1968-07-01

Trace analysis in solids by spark source mass spectrometry involves complicated phenomena: element ionization in spark and blacking of sensitive emulsion by focused ion beam. However the principal risk of selectivity lies in analyser system, which realizes double focusing only for a part of the ions. Therefore, each analyst has to known ionic optics of his apparatus, for ensuring the transmission of mean energetic ions, which are representative of sample composition. By a careful photometry of mass spectrum, good reproducibility can be obtained. Thereafter accuracy depends on the knowledge of sensitivity coefficients proper to this apparatus. (author) [French] L'analyse de traces dans les solides par spectrometrie de masse a etincelles met en jeu des phenomenes complexes qui sont l'ionisation des elements dans l'etincelle, et le noircissement de l'emulsion sensible par les faisceaux ioniques focalises. Cependant, le risque majeur de selectivite provient de l'ensemble analyseur, qui realise la double focalisation sur une fraction seulement du faisceau d'ions. L'analyste doit donc connaitre en detail l'optique ionique de son appareil, pour assurer le passage de la bande d'energie moyenne des ions, qui seule caracterise quantitativement la composition chimique de l'echantillon. Une exploitation photometrique soignee du spectrogramme donne alors des resultats reproductibles, dont la justesse ne depend plus que des coefficients de sensibilite propres a ce type d'instrument. (auteur)

Activation analysis using {gamma} photons; Analyse par activation aux photons {gamma}

Energy Technology Data Exchange (ETDEWEB)

Engelmann, Ch [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-07-01

This report summarizes all the data required for using photonuclear reactions in the field of analysis. After a brief review of the elementary properties of nuclear reactions induced by photon irradiation, the main characteristics are given of high energy (E > 20 MeV) Bremsstrahlung sources. The principle of activation analysis based on the use of photons is given. Actual examples of the analytic possibilities are described in detail, in particular in the case of the determination of very small quantities (< 10{sup -6}) of C, N, O and F. The influence of interfering nuclear reactions is discussed. (author) [French] Ce rapport se propose de resumer l'ensemble des connaissances indispensables pour l'utilisation des reactions photonucleaires a des fins analytiques. Apres quelques rappels concernant les proprietes elementaires des reactions nucleaires induites par irradiation dans les photons, les principales caracteristiques des sources de rayonnement de freinage de haute energie (E > 20 MeV)| sont donnees. Le principe de l'analyse par activation aux photons est rappele. Des exemples concrets sur les possibilites analytiques sont developpes, particulierement en ce qui concerne la determination de quantites tres faibles (< 10{sup -6}) de C, N, O et F. L'influence des reactions nucleaires parasites est discutee. (auteur)

Coupling Front-End Separations, Ion Mobility Spectrometry, and Mass Spectrometry For Enhanced Multidimensional Biological and Environmental Analyses

Science.gov (United States)

Zheng, Xueyun; Wojcik, Roza; Zhang, Xing; Ibrahim, Yehia M.; Burnum-Johnson, Kristin E.; Orton, Daniel J.; Monroe, Matthew E.; Moore, Ronald J.; Smith, Richard D.; Baker, Erin S.

2017-01-01

Ion mobility spectrometry (IMS) is a widely used analytical technique for rapid molecular separations in the gas phase. Though IMS alone is useful, its coupling with mass spectrometry (MS) and front-end separations is extremely beneficial for increasing measurement sensitivity, peak capacity of complex mixtures, and the scope of molecular information available from biological and environmental sample analyses. In fact, multiple disease screening and environmental evaluations have illustrated that the IMS-based multidimensional separations extract information that cannot be acquired with each technique individually. This review highlights three-dimensional separations using IMS-MS in conjunction with a range of front-end techniques, such as gas chromatography, supercritical fluid chromatography, liquid chromatography, solid-phase extractions, capillary electrophoresis, field asymmetric ion mobility spectrometry, and microfluidic devices. The origination, current state, various applications, and future capabilities of these multidimensional approaches are described in detail to provide insight into their uses and benefits. PMID:28301728

Coupling Front-End Separations, Ion Mobility Spectrometry, and Mass Spectrometry For Enhanced Multidimensional Biological and Environmental Analyses

Energy Technology Data Exchange (ETDEWEB)

Zheng, Xueyun; Wojcik, Roza; Zhang, Xing; Ibrahim, Yehia M.; Burnum-Johnson, Kristin E.; Orton, Daniel J.; Monroe, Matthew E.; Moore, Ronald J.; Smith, Richard D.; Baker, Erin M.

2017-06-12

Ion mobility spectrometry (IMS) is a widely used analytical technique for rapid molecular separations in the gas phase. IMS alone is useful, but its coupling with mass spectrometry (MS) and front-end separations has been extremely beneficial for increasing measurement sensitivity, peak capacity of complex mixtures, and the scope of molecular information in biological and environmental sample analyses. Multiple studies in disease screening and environmental evaluations have even shown these IMS-based multidimensional separations extract information not possible with each technique individually. This review highlights 3-dimensional separations using IMS-MS in conjunction with a range of front-end techniques, such as gas chromatography (GC), supercritical fluid chromatography (SFC), liquid chromatography (LC), solid phase extractions (SPE), capillary electrophoresis (CE), field asymmetric ion mobility spectrometry (FAIMS), and microfluidic devices. The origination, current state, various applications, and future capabilities for these multidimensional approaches are described to provide insight into the utility and potential of each technique.

Thermodynamic study of sulphur hemi-oxide using mass spectrometry (1963); Etude thermodynamique de l'hemioxyde de soufre par spectrometry de masse (1963)

Energy Technology Data Exchange (ETDEWEB)

Hagemann, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-01-15

have also examined the work concerning the heat of formation of SO to discover whether the formation of SO is possible between 1000 deg K and 1500 deg K starting from sulphur and SO{sub 2}. (author) [French] L'action de l'oxygene sur le soufre, a basse pression, dons une decharge haute frequence, a ete etudiee en analysant en continu, les produits de la reaction par spectrometrie de masse. Les spectres de masse du gaz issu de la decharge correspondent a un melange SO{sub 2}, S{sub 2}O, S{sub 2} et O{sub 2}. Nous avons mesure jusqu'a 75 pour rent de SO{sub 2} dans le melange SO{sub 2} + S{sub 2}O. Nous avons conclu a l'absence des molecules S{sub 2}O{sub 2}, et SO dans le melange. Les potentiels d'ionisation des molecules, et d'apparition des ions fragments du melange issu de la decharge, ont ete etudies par spectrometrie de masse. La chaleur de formation de S{sub 2}O a ete estimee a partir des mesures des potentiels d'apparition des ions SO{sup +} provenant de SO{sub 2}, et S{sub 2}O. (- 18.5 kcal/mole - < {delta}H, (S{sub 2}O{sub g}) < - 7 kcal/mole). Nous avons ete amenes a mesurer les potentiels d'ionisation des molecules S{sub 2}, S{sub 4}, S{sub 6} et S{sub 8} dont les valeurs sont respectivement: 9,7 {+-} 0,1 eV; 10,4 {+-} 0,5 eV; 8,5 {+-} 0,3 eV et 7,3 {+-} 0,3 eV. Nous avons enfin etudie l'equilibre de formation de StO a partir de soufre et de S{sub 2}O, dans un reacteur a filaments chauds. La mesure de la variation, entre 1100 deg K et 1500 deg K. de h constante d'equilibre de la reaction: SO{sub 2} + 3/2 S{sub 2} {r_reversible} 2 S{sub 2}O a permis de determiner la variation d'enthalpie de cette reaction ({delta}H = 5310 {+-} 370 calories) La somme d'etats de la molecule S{sub 2}O, Z{sup 0}, a ete calculee a partir des donnees bibliographiques. En appliquant a l'equilibre de formation de S{sub 2}O l'equation: Log K{sub p} = {delta}Log Z{sup 0}/N - {delta}H{sup 0}{sub 0}/RT nous avons calcule l'enthalpie de ia reaction au zero absolu ({delta}H{sup 0}{sub 0

Isotopic analysis of plutonium by optical spectroscopy; Analyse isotopique du plutonium par spectroscopie optique

Energy Technology Data Exchange (ETDEWEB)

Artaud, J; Chaput, M; Gerstenkorn, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

Isotopic analysis of mixtures of plutonium 239 and 240 has been carried out by means of the photo-electric spectrometer Fabry-Perot, the source being a hollow cathode cooled by liquid nitrogen. This first research has been concerned with finding among the spectral lines given by the hollow cathode, those suitable for use in analysis. Actually, the relative precision is of the order of 2 per cent (for samples containing 3 per cent of {sup 240}Pu). The study of the reproducibility of the measurements should make it possible to increase the precision; the relative precision which can be expected from this method should be 1 per cent for mixtures containing 1 per cent of {sup 240}Pu. (author) [French] L'analyse isotopique des melanges de plutonium 239 et 240 a ete effectuee a l'aide du spectrometre photoelectrique Fabry-Perot, la source etant une cathode creuse refroidie a l'azote liquide. Ce premier travail a eu pour but de discerner parmi les raies spectrales emises par la cathode creuse, celles susceptibles de servir de raies d'analyse. Actuellement, la precision relative est de l'ordre de 2 pour cent (pour des echantillons contenant 3 pour cent de {sup 240}Pu). L'etude de la reproductibilite des mesures devrait permettre d'ameliorer la precision; la precision relative que l'on pourrait atteindre par cette methode serait de 1 pour cent pour des melanges contenant 1 pour cent de {sup 240}Pu. (auteur)

Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966); Etude de la radioactivite artificielle du milieu marin par spectrometrie gamma (1962-1966)

Energy Technology Data Exchange (ETDEWEB)

Chesselet, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [French] Les resultats decrits dans cette etude concernent la radioactivite artificielle sous forme de zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 et praseodyme-144 apportee par la retombee atmospherique entre 1962 et 1964 et les

Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966); Etude de la radioactivite artificielle du milieu marin par spectrometrie gamma (1962-1966)

Energy Technology Data Exchange (ETDEWEB)

Chesselet, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [French] Les resultats decrits dans cette etude concernent la radioactivite artificielle sous forme de zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 et praseodyme-144 apportee par la retombee

Fourier Transform Mass Spectrometry: The Transformation of Modern Environmental Analyses

Science.gov (United States)

Lim, Lucy; Yan, Fangzhi; Bach, Stephen; Pihakari, Katianna; Klein, David

2016-01-01

Unknown compounds in environmental samples are difficult to identify using standard mass spectrometric methods. Fourier transform mass spectrometry (FTMS) has revolutionized how environmental analyses are performed. With its unsurpassed mass accuracy, high resolution and sensitivity, researchers now have a tool for difficult and complex environmental analyses. Two features of FTMS are responsible for changing the face of how complex analyses are accomplished. First is the ability to quickly and with high mass accuracy determine the presence of unknown chemical residues in samples. For years, the field has been limited by mass spectrometric methods that were based on knowing what compounds of interest were. Secondly, by utilizing the high resolution capabilities coupled with the low detection limits of FTMS, analysts also could dilute the sample sufficiently to minimize the ionization changes from varied matrices. PMID:26784175

Ion-exchange resin separation applied to activation analysis (1963); Separation par resines echangeuses d'ions appliquees a l'analyse par activation (1963)

Energy Technology Data Exchange (ETDEWEB)

Aubouin, G; Laverlochere, J [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1963-07-01

The separation techniques based on ion-exchange resins have been used, in this study, for carrying out activation analyses on about thirty impurities. A separation process has been developed so as to standardise these analyses and to render them execution a matter of routine. The reparation yields obtained are excellent and make it possible to carry out analyses on samples having a large activation cross-section ween working inside a reinforced fume-cupboard. This technique has been applied to the analysis of impurities in tantalum, iron, gallium, germanium, terphenyl, and tungsten. The extension of this process to other impurities and to other matrices is now being studied. (authors) [French] Les techniques de separations sur resines echangeusee d'ions ont ete utilisees, dans cette etude, pour effectuer des analyses par activation sur une trentaine d'impuretes. Un schema de separation a ete mis au point de maniere a normaliser ces analyses et a pouvoir les faire en routine. Les rendements de separation obtenus sont excellents et permettent de proceder a des analyses d'echantillons a grande section efficace d'activation en travaillant dans une sorbonne blindee. Des applications de cette technique ont ete faites pour des analyses d'impuretes dans le tantale, le fer, le gallium, le germanium, le terphenyle, le tungstene. L'extension de ce schema a d'autres impuretes et a d'autres matrices est en cours d'etude. (auteurs)

Use of the helium-3 proportional counter for neutron spectrometry; Utilisation du compteur proportionnel a helium 3 pour la spectrometrie des neutrons

Energy Technology Data Exchange (ETDEWEB)

Vialettes, H; Le Thanh, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-07-01

Up to now, two methods have been mainly used for neutron spectrometry near nuclear installations: - photographic emulsion spectrometry - the so-called, 'multisphere' technique spectrometry. The first method, which is fairly difficult to apply, has a threshold energy of about 500 keV; this is a big disadvantage for an apparatus which has to be used for spectrometry around nuclear installations where the neutron radiation is very much degraded energetically. The second method does not suffer from this disadvantage but the results which it yields are only approximate. In order to extend the energy range of the neutron spectra studied with sufficient accuracy the use of a helium-3 proportional counter has been considered. This report presents the principles of operation of the helium-3 spectrometer, and the calculation methods which make it possible to take into account the two main effects tending to deform the spectra obtained: - energy absorption by the walls of the counter, - energy loss of the incident neutrons due to elastic collisions with helium-3 nuclei. As an example of the application, the shape of the neutron spectrum emitted by a polonium-lithium source is given; the results obtained are in excellent agreement with theoretical predictions. (authors) [French] Jusqu'ici deux methodes ont ete utilisees principalement pour la spectrometrie des neutrons autour des installations nucleaires: - la spectrometrie par emulsions photographiques - la spectrometrie par la technique dite des multispheres. La premiere methode, d'un emploi assez delicat presente un seuil en energie d'environ 500 keV qui est un obstacle serieux a la spectrometrie autour des installations nucleaires ou le rayonnement neutronique est tres degrade en energie. La deuxieme methode ne presente pas cet inconvenient mais les resultats qu'elle permet d'obtenir ne sont qu'approches. Pour etendre la gamme d'energie des spectres de neutrons etudies avec une precision suffisante, l'utilisation du

Fourier Transform Mass Spectrometry: The Transformation of Modern Environmental Analyses

Directory of Open Access Journals (Sweden)

Lucy Lim

2016-01-01

Full Text Available Unknown compounds in environmental samples are difficult to identify using standard mass spectrometric methods. Fourier transform mass spectrometry (FTMS has revolutionized how environmental analyses are performed. With its unsurpassed mass accuracy, high resolution and sensitivity, researchers now have a tool for difficult and complex environmental analyses. Two features of FTMS are responsible for changing the face of how complex analyses are accomplished. First is the ability to quickly and with high mass accuracy determine the presence of unknown chemical residues in samples. For years, the field has been limited by mass spectrometric methods that were based on knowing what compounds of interest were. Secondly, by utilizing the high resolution capabilities coupled with the low detection limits of FTMS, analysts also could dilute the sample sufficiently to minimize the ionization changes from varied matrices.

Mass Spectrometry Analyses of Multicellular Tumor Spheroids.

Science.gov (United States)

Acland, Mitchell; Mittal, Parul; Lokman, Noor A; Klingler-Hoffmann, Manuela; Oehler, Martin K; Hoffmann, Peter

2018-05-01

Multicellular tumor spheroids (MCTS) are a powerful biological in vitro model, which closely mimics the 3D structure of primary avascularized tumors. Mass spectrometry (MS) has established itself as a powerful analytical tool, not only to better understand and describe the complex structure of MCTS, but also to monitor their response to cancer therapeutics. The first part of this review focuses on traditional mass spectrometry approaches with an emphasis on elucidating the molecular characteristics of these structures. Then the mass spectrometry imaging (MSI) approaches used to obtain spatially defined information from MCTS is described. Finally the analysis of primary spheroids, such as those present in ovarian cancer, and the great potential that mass spectrometry analysis of these structures has for improved understanding of cancer progression and for personalized in vitro therapeutic testing is discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Analyse des solides déformables par la méthode des éléments finis

CERN Document Server

Bonnet, Marc

2006-01-01

Cet ouvrage propose une présentation structurée de la formulation et la mise en œuvre de la simulation numérique par éléments finis en mécanique des solides déformables. Il présente et développe les concepts et techniques permettant la transposition, en termes de codes de calcul de structures mécaniques industrielles, des notions fondamentales de mécanique des milieux continus solides, et ce dans le cadre d'analyses en régimes (a) statique linéaire, (b) quasistatique non-linéaire et (c) dynamique linéaire. L'exposé théorique est complété et illustré au moyen de programmes d'initiation écrits en Matlab (librement accessibles par Internet) mettant en œuvre les notions développées dans cet ouvrage et conçus comme support pratique à un enseignement. Le texte combine ainsi l'exposition des principes et des méthodes avec la présentation détaillée de ces programmes et d'exemples les mettant en œuvre. L'ouvrage est complété d'une annexe écrite par Andrei Constantinescu (directeur de...

Comprendre le développement professionnel par l’analyse des discours

Directory of Open Access Journals (Sweden)

Sabine Vanhulle

2011-07-01

Full Text Available Dans un dispositif consacré au développement professionnel, nos étudiants en enseignement secondaire tiennent un portfolio. Celui-ci se clôture par un récit de trajectoire. Notre recherche réside dans l’analyse de ces récits à partir d’une grille d’indicateurs linguistiques. Ces indicateurs nous informent sur les processus réflexifs et discursifs à l’œuvre dans l’élaboration de savoirs professionnels. Ce premier niveau de description conduit à une méthode de recherche herméneutique. Il s’agit alors de mettre en lumière les préoccupations sous-jacentes à ces processus : systèmes de valeurs, de motivations et d’intentions ; tensions entre les savoirs scientifiques et la confrontation aux réalités vécues dans l’expérience ; constructions identitaires conflictuelles. Nous questionnons les conditions sociales externes et propres au contexte de formation qui influencent la production de ces récits. Nous en dégageons les implications méthodologiques pour l’analyse de discours à visée descriptive et compréhensive. Sur cette base, nous discutons quelques résultats de la recherche.Mots-clés : Portfolio. Savoirs professionnels écrits. Indicateurs de développement. Formation des valeurs. Herméneutique.

Isotope analysis by emission spectroscopy; Analyse isotopique par spectroscopie d'emission

Energy Technology Data Exchange (ETDEWEB)

Artaud, J; Gerstenkorn, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Blaise, J [Centre National de la Recherche Scientifique (CNRS), Lab. Aime Cotton, 92 - Meudon-Bellevue (France)

1959-07-01

Quantitative analysis of isotope mixtures by emission spectroscopy is resulting from the phenomenon called 'isotope shift', say from the fact that spectral lines produced by a mixture of isotopes of a same element are complex. Every spectral line is, indeed, resulting from several lines respectively corresponding to each isotope. Then isotopic components are near one to others, and their separation is effected by means of Fabry-Perot calibration standard: the apparatus allowing to measure abundances is the Fabry-Perot photo-electric spectrometer, designed in 1948 by MM. JACQUINOT and DUFOUR. This method has been used to make abundance determination in the case of helium, lithium, lead and uranium. In the case of lithium, the utilised analysis line depends on the composition of examined isotopic mixture. For mixtures containing 7 to 93 pour cent of one of isotopes of lithium, this line is the lithium blue line: {lambda} = 4603 angstrom. In other cases the red line {lambda} = 6707 angstrom is preferable, though it allows to do easily nothing but relative determinations. Helium shows no particular difficulty and the analysis line selected was {lambda} = 6678 angstrom. For lead the line {lambda} = 5201 angstrom gives the possibility to determine the isotope abundance for the four isotopes of lead notwithstanding the presence of hyperfine structure of {sup 207}Pb. For uranium, line {lambda} 5027 angstrom is used, and this method allows to determine the composition of isotope mixtures, the content of which in {sup 235}U may shorten to 0,1 per cent. Relative precision is about 2 per cent for contents in {sup 235}U over 1 per cent. For lower contents, this line {lambda} = 5027 angstrom will allow relative measures when using previously dosed mixtures. (author) [French] L'analyse quantitative des melanges isotopiques par spectroscopie d'emission doit son existence au phenomene appele 'deplacement isotopique', c'est-a-dire au fait que les raies spectrales emises par un

Multielemental analyses of tree rings by inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Hall, G.S.

1990-01-01

Inductively coupled plasma mass spectrometry (ICP-MS) was evaluated for major, minor, trace, and ultra-trace elemental analyses of individual tree rings. The samples were obtained from an old-growth Douglas fir growing near Mount St. Helens volcano, and from trees at various other North American sites. Eightly percent of elements from Li to U had detection limits in the solid (wood) below 8.0 ng g -1 . Two anomalous peaks occur in Mount St. Helens samples at A.D. 1478 and 1490 that closely correlate with past eruptions of the volcano. These results show that ICP-MS is a rapid and sensitive analytical method for multielemental analyses of individual tree rings. (author) 16 refs.; 2 figs.; 2 tabs

Ion-exchange resin separation applied to activation analysis (1963); Separation par resines echangeuses d'ions appliquees a l'analyse par activation (1963)

Energy Technology Data Exchange (ETDEWEB)

Aubouin, G.; Laverlochere, J. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1963-07-01

The separation techniques based on ion-exchange resins have been used, in this study, for carrying out activation analyses on about thirty impurities. A separation process has been developed so as to standardise these analyses and to render them execution a matter of routine. The reparation yields obtained are excellent and make it possible to carry out analyses on samples having a large activation cross-section ween working inside a reinforced fume-cupboard. This technique has been applied to the analysis of impurities in tantalum, iron, gallium, germanium, terphenyl, and tungsten. The extension of this process to other impurities and to other matrices is now being studied. (authors) [French] Les techniques de separations sur resines echangeusee d'ions ont ete utilisees, dans cette etude, pour effectuer des analyses par activation sur une trentaine d'impuretes. Un schema de separation a ete mis au point de maniere a normaliser ces analyses et a pouvoir les faire en routine. Les rendements de separation obtenus sont excellents et permettent de proceder a des analyses d'echantillons a grande section efficace d'activation en travaillant dans une sorbonne blindee. Des applications de cette technique ont ete faites pour des analyses d'impuretes dans le tantale, le fer, le gallium, le germanium, le terphenyle, le tungstene. L'extension de ce schema a d'autres impuretes et a d'autres matrices est en cours d'etude. (auteurs)

Investigation of aluminium and manganese uptake in Congolese flora by activation analysis; Recherche d'accumulateurs D’ Aluminium Et De Manganese Dans La Flore Congolaise Par La Methode D'Analyse Par Activation

Energy Technology Data Exchange (ETDEWEB)

Evrard, C.; Roels, J.; Pauwels, L.; Pollak, H. [Centre nucléaire TRICO, Kinshasa (Congo, The Democratic Republic of the); Université Lovanium, Kinshasa (Congo, The Democratic Republic of the)

1970-01-15

It is known that certain plants accumulate one or more elements in their tissues. This characteristic can make a valuable contribution to the taxonomy of groups, families and even of species. The ecology characteristic of each species may also be demonstrated by the accumulation of certain elements. Soil acidity can have a strong effect on accumulation. High acidity favours the accumulation of manganese, for example. The authors have endeavoured to perfect a technique of analysis based on neutron activation (nondestructive). Thermal neutron activation is carried out in the TRIGA Mk I reactor of the TRICO Nuclear Centre, which has a flux of about 10{sup 11}n cm{sup -2} s{sup -1}. Activation analysis is quicker than chemical methods and has the additional advantage that it can be used for small quantities of plant material. At least forty species of local plants have been tested. In addition to these specific tests, we have analysed leaves from trees of a given species growing in different soils, in order to get some idea of individual variations from one plant to another. (author) [French] Il est connu que certaines plantes accumulent un ou plusieurs éléments dans leurs tissus. Cette particularité peut apporter une précieuse contribution à la taxonomie des groupes, des familles ou même des espèces. L'écologie propre â chaque espèce peut aussi être mise en évidence par l'accumulation de certains éléments. Le degré d'acidité du sol, par exemple, peut fortement influencer cette accumulation. Dans le cas de manganèse, une forte acidité du sol favorise l'accumulation de cet élément. Les auteurs ont cherché à mettre au point une méthode d'analyse par activation neutronique (non destructive). Les activations aux neutrons thermiques ont été effectuées dans le réacteur TRIGA Mk I du Centre nucléaire TRICO, dans un flux d'environ 10{sup 11} n cm{sup -2} sec{sup -1}. Comparée à la méthode chimique, l'analyse par activation est plus rapide et peut

The double par locus of virulence factor pB171: DNA segregation is correlated with oscillation of ParA

DEFF Research Database (Denmark)

Ebersbach, G; Gerdes, K; Charbon, Gitte Ebersbach

2001-01-01

Prokaryotic plasmids and chromosomes encode partitioning (par) loci that segregate DNA to daughter cells before cell division. Recent database analyses showed that almost all known par loci encode an ATPase and a DNA-binding protein, and one or more cis-acting regions where the proteins act. All...

The use of mass spectrometry for analysing metabolite biomarkers in epidemiology

DEFF Research Database (Denmark)

Lind, Mads Vendelbo; Savolainen, Otto I; Ross, Alastair B

2016-01-01

measurement tools. One tool that is increasingly being used for measuring biomarkers in epidemiological cohorts is mass spectrometry (MS), because of the high specificity and sensitivity of MS-based methods and the expanding range of biomarkers that can be measured. Further, the ability of MS to quantify many...... biomarkers simultaneously is advantageously compared to single biomarker methods. However, as with all methods used to measure biomarkers, there are a number of pitfalls to consider which may have an impact on results when used in epidemiology. In this review we discuss the use of MS for biomarker analyses...

Leçons d’analyse classique exposition d'un cours fait par Paul Koosis à l'Université McGill, Montréal

CERN Document Server

Poulin, Philippe

2015-01-01

Ce livre est basé sur un cours de deuxième cycle donné en 2005-2006 par M. Paul Koosis, professeur émérite à l'université McGill. Il traite de sujets soigneusement choisis par le professeur à l'intention de ceux qui, plutôt que de rechercher un catalogue exhaustif de résultats techniques et abstraits, veulent être initiés aux découvertes les plus essentielles et prolifiques de l'analyse classique du vingtième siècle. Analyse harmonique, quasi-analyticité, zéros des fonctions entières (dont une preuve inédite du théorème de Levinson-Cartwright), approximation pondérée, principe d'incertitude, mesures harmoniques…, les résultats saillants et géniaux de l'analyse classique sont présentés dans un style soigné, rigoureux et détaillé, préparant les étudiants à des études plus poussées ; et au service du lecteur qui, connaissant les bases de la théorie de la mesure et de l'analyse complexe, désire suivre le merveilleux développement de M. Koosis et accroître sa connaissance d...

Mass-spectrometric analysis of trace oxygen in carbon dioxide; Analyse de traces d'oxygene dans le gaz carbonique par spectrometrie de masse

Energy Technology Data Exchange (ETDEWEB)

Nief, G; Severin, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1961-07-01

The mass spectrum of pure CO{sub 2} contains a peak of weight 32 whose relationship to peak at 44 varies greatly depending on the previous history of the source of ions and even during the course of an analysis. The fact that this peak is more or less proportional to the pressure and that its appearance potential is the same as that of oxygen leads us to suppose that it is produced from oxygen formed by dissociation of the carbon dioxide on the tungsten filament. A prior treatment of the ion source with acetylene reduces the ratio 32/44 to a value of about 15.10{sup -5}. This same treatment also stabilises the spectrometer's sensitivity to oxygen. Two lines of introduction enable pure carbon dioxide, the specimen to be estimated and a reference mixture of known oxygen content to be sent into the mass spectrometer in quick succession. Oxygen in the carbon dioxide in amounts ranging between 0 and 500 p.p.m. can thus be determined to an accuracy of {+-} 5 p.p.m., the analysis taking 30 minutes. (author) [French] Le spectre de masse de CO{sub 2} pur contient un pic de masse 32 dont le rapport au pic 44 varie enormement suivant l'histoire anterieure de la source d'ions et meme au cours d'une analyse. Le fait que ce pic soit grossierement proportionnel a la pression et que son potentiel d'apparition soit le meme que celui de l'oxygene permet de supposer qu'il est engendre a partir de l'oxygene produit par dissociation du gaz carbonique sur le filament de tungstene. Un conditionnement prealable de la source d'ions avec de l'acetylene reduit le rapport 32/44 a une valeur d'environ 15.10{sup -5}. Ce meme traitement stabilise egalement la sensibilite du spectrometre vis-a-vis de l'oxygene. Une double ligne d'introduction de gaz permet d'envoyer en successions rapides dans le spectrometre de masse le gaz carbonique pur, l'echantillon a doser et un melange de reference de teneur en oxygene connue. On arrive ainsi a doser l'oxygene dans le gaz carbonique dans la gamme de 0 a

MULTI-DIMENSIONAL MASS SPECTROMETRY-BASED SHOTGUN LIPIDOMICS AND NOVEL STRATEGIES FOR LIPIDOMIC ANALYSES

Science.gov (United States)

Han, Xianlin; Yang, Kui; Gross, Richard W.

2011-01-01

Since our last comprehensive review on multi-dimensional mass spectrometry-based shotgun lipidomics (Mass Spectrom. Rev. 24 (2005), 367), many new developments in the field of lipidomics have occurred. These developments include new strategies and refinements for shotgun lipidomic approaches that use direct infusion, including novel fragmentation strategies, identification of multiple new informative dimensions for mass spectrometric interrogation, and the development of new bioinformatic approaches for enhanced identification and quantitation of the individual molecular constituents that comprise each cell’s lipidome. Concurrently, advances in liquid chromatography-based platforms and novel strategies for quantitative matrix-assisted laser desorption/ionization mass spectrometry for lipidomic analyses have been developed. Through the synergistic use of this repertoire of new mass spectrometric approaches, the power and scope of lipidomics has been greatly expanded to accelerate progress toward the comprehensive understanding of the pleiotropic roles of lipids in biological systems. PMID:21755525

Contribution to the study of the geophysical behaviour of lead-210 by application of alpha spectrometry; Contribution a l'etude du comportement geophysique du plomb 210 par application de la spectrometrie alpha

Energy Technology Data Exchange (ETDEWEB)

Nezami, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-06-01

A study of the changes in the lead-210 contents of rain-water and of water produced by melting polar ice has required the development of a method for dosing lead-210, an {alpha} emitter. This method is 40 times more sensitive than that which measures the lead-210 by bismuth-210, a ({beta} emitter. The first part of the report presents the study of a spectrometry using semiconductor detectors; a catalogue of a spectra shows the advantages of this method. In the second part will be found at first a new chemical separation method for polonium-210 and the results obtained with this method. The main results obtained on the geophysical behaviour of lead-210 are the following: - the monthly lead-210 and polonium-210 contents in rain water are approximately constant with time. - in the Gif-sur-Yvette region, the clean-up by 'dry fall-out' can attain 40 to 50 per cent of the total fall-out. - a study of Antarctic ice samples makes it possible to determine an annual accumulation rate equivalent to 13.8 cm of water and to show discrepancies in the periodic concentrations which correspond to the latest maxima of solar activity. - a balance is drawn up between the radon produced by the continents and the lead-210 fall-out. (author) [French] Une etude sur les variations de la teneur en plomb 210 des eaux de pluie et des eaux de fusion des glaces polaires a necessite la mise au point d'une methode de dosage du plomb 210 emetteur {alpha}. Cette methode permet d'obtenir une sensibilite quarante fois superieure a celle dosant le plomb 210 par le bismuth 210 emetteur {beta}. La premiere partie du travail presente l'etude de la spectrometrie {alpha} par detecteur a semiconducteurs, un catalogue de spectres {alpha} met en evidence les avantages de cette methode. Dans la deuxieme partie on trouvera en premier lieu une nouvelle methode chimique de separation du polonium 210 ainsi que les resultats obtenus grace a cette methode. Les principaux resultats sur le comportement geophysique du

Analysis of electronic circuits using digital computers; L'analyse des circuits electroniques par les calculateurs numeriques

Energy Technology Data Exchange (ETDEWEB)

Tapu, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1968-07-01

Various programmes have been proposed for studying electronic circuits with the help of computers. It is shown here how it possible to use the programme ECAP, developed by I.B.M., for studying the behaviour of an operational amplifier from different point of view: direct current, alternating current and transient state analysis, optimisation of the gain in open loop, study of the reliability. (author) [French] Differents programmes ont ete proposes pour l'etude des circuits electroniques a l'aide des calculateurs. On montre comment on peut utiliser le programme ECAP, mis au point par I. B. M., pour etudier le comportement d'un amplificateur operationnel, a differents points de vue: analyse en courant continu, courant alternatif et regime transitoire, optimalisation du gain en boucle ouverte, etude de la fiabilite. (auteur)

Numerical analysis of resonances induced by s wave neutrons in transmission time-of-flight experiments with a computer IBM 7094 II; Methodes d'analyse des resonances induites par les neutrons s dans les experiences de transmission par temps de vol et automatisation de ces methodes sur ordinateur IBM 7094 II

Energy Technology Data Exchange (ETDEWEB)

Corge, Ch [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-01-01

Numerical analysis of transmission resonances induced by s wave neutrons in time-of-flight experiments can be achieved in a fairly automatic way on an IBM 7094/II computer. The involved computations are carried out following a four step scheme: 1 - experimental raw data are processed to obtain the resonant transmissions, 2 - values of experimental quantities for each resonance are derived from the above transmissions, 3 - resonance parameters are determined using a least square method to solve the over determined system obtained by equalling theoretical functions to the correspondent experimental values. Four analysis methods are gathered in the same code, 4 - graphical control of the results is performed. (author) [French] L'automatisation, sur ordinateur IBM 7094/II, de l'analyse des resonances induites par les neutrons s dans les experiences de transmission par temps de vol a ete accomplie en la decomposant selon un schema articule en quatre phases: 1 - le traitement des donnees experimentales brutes pour obtenir les transmissions interfero-resonnantes, 2 - la determination des grandeurs d'analyse a partir des transmissions precedentes, 3 - l'analyse proprement dite des resonances dont les parametres sont obtenus par la resolution d'un systeme surabondant. Quatre methodes d'analyse sont groupees en un meme programme, 4 - la procedure de verification graphique. (auteur)

Contribution to the study of the geophysical behaviour of lead-210 by application of alpha spectrometry; Contribution a l'etude du comportement geophysique du plomb 210 par application de la spectrometrie alpha

Energy Technology Data Exchange (ETDEWEB)

Nezami, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-06-01

A study of the changes in the lead-210 contents of rain-water and of water produced by melting polar ice has required the development of a method for dosing lead-210, an {alpha} emitter. This method is 40 times more sensitive than that which measures the lead-210 by bismuth-210, a ({beta} emitter. The first part of the report presents the study of a spectrometry using semiconductor detectors; a catalogue of a spectra shows the advantages of this method. In the second part will be found at first a new chemical separation method for polonium-210 and the results obtained with this method. The main results obtained on the geophysical behaviour of lead-210 are the following: - the monthly lead-210 and polonium-210 contents in rain water are approximately constant with time. - in the Gif-sur-Yvette region, the clean-up by 'dry fall-out' can attain 40 to 50 per cent of the total fall-out. - a study of Antarctic ice samples makes it possible to determine an annual accumulation rate equivalent to 13.8 cm of water and to show discrepancies in the periodic concentrations which correspond to the latest maxima of solar activity. - a balance is drawn up between the radon produced by the continents and the lead-210 fall-out. (author) [French] Une etude sur les variations de la teneur en plomb 210 des eaux de pluie et des eaux de fusion des glaces polaires a necessite la mise au point d'une methode de dosage du plomb 210 emetteur {alpha}. Cette methode permet d'obtenir une sensibilite quarante fois superieure a celle dosant le plomb 210 par le bismuth 210 emetteur {beta}. La premiere partie du travail presente l'etude de la spectrometrie {alpha} par detecteur a semiconducteurs, un catalogue de spectres {alpha} met en evidence les avantages de cette methode. Dans la deuxieme partie on trouvera en premier lieu une nouvelle methode chimique de separation du polonium 210 ainsi que les resultats obtenus grace a cette methode. Les principaux resultats sur le

Isotopic analysis of uranium hexafluoride highly enriched in U-235; Analyse isotopique de l'hexafluorure d'uranium fortement enrichi en U 235

Energy Technology Data Exchange (ETDEWEB)

Chaussy, L; Boyer, R [Commissariat a l' Energie Atomique, Pierrelatte (France). Centre d' Etudes Nucleaires

1968-07-01

Isotopic analysis of uranium in the form of the hexafluoride by mass-spectrometry gives gross results which are not very accurate. Using a linear interpolation method applied to two standards it is possible to correct for this inaccuracy as long as the isotopic concentrations are less than about 10 per cent in U-235. Above this level, the interpolations formula overestimates the results, especially if the enrichment of the analyzed samples is higher than 1.3 with respect to the standards. A formula is proposed for correcting the interpolation equation and for the extending its field of application to high values of the enrichment ({approx_equal}2) and of the concentration. It is shown that by using this correction the results obtained have an accuracy which depends practically only on that of the standards, taking into account the dispersion in the measurements. (authors) [French] L'analyse isotopique de l'uranium sous forme d'hexafluorure, par spectrometrie de masse, fournit des resultats bruts entaches d'inexactitude. Une methode d'interpolation lineaire entre deux etalons permet de corriger cette inexactitude, tant que les concentrations isotopiques sont inferieures a 10 pour cent en U-235 environ. Au-dessus de cette valeur, la formule d'interpolation surestime les resultats, notamment si l'enrichissement des echantillons analyses par rapport aux etalons est superieur a 1,3. On propose une formule de correction de l'equation d'interpolation qui etend son domaine d'application jusqu'a des valeurs elevees d'enrichissement ({approx_equal}2) et de concentration. On montre experimentalement que par cette correction, les resultats atteignent, a la precision des mesures, une exactitude qui ne depend pratiquement plus que de celles des etalons. (auteurs)

Accelerator mass spectrometry analyses of environmental radionuclides: sensitivity, precision and standardisation

Science.gov (United States)

Hotchkis; Fink; Tuniz; Vogt

2000-07-01

Accelerator Mass Spectrometry (AMS) is the analytical technique of choice for the detection of long-lived radionuclides which cannot be practically analysed with decay counting or conventional mass spectrometry. AMS allows an isotopic sensitivity as low as one part in 10(15) for 14C (5.73 ka), 10Be (1.6 Ma), 26Al (720 ka), 36Cl (301 ka), 41Ca (104 ka), 129I (16 Ma) and other long-lived radionuclides occurring in nature at ultra-trace levels. These radionuclides can be used as tracers and chronometers in many disciplines: geology, archaeology, astrophysics, biomedicine and materials science. Low-level decay counting techniques have been developed in the last 40-50 years to detect the concentration of cosmogenic, radiogenic and anthropogenic radionuclides in a variety of specimens. Radioactivity measurements for long-lived radionuclides are made difficult by low counting rates and in some cases the need for complicated radiochemistry procedures and efficient detectors of soft beta-particles and low energy x-rays. The sensitivity of AMS is unaffected by the half-life of the isotope being measured, since the atoms not the radiations that result from their decay, are counted directly. Hence, the efficiency of AMS in the detection of long-lived radionuclides is 10(6)-10(9) times higher than decay counting and the size of the sample required for analysis is reduced accordingly. For example, 14C is being analysed in samples containing as little as 20 microg carbon. There is also a world-wide effort to use AMS for the analysis of rare nuclides of heavy mass, such as actinides, with important applications in safeguards and nuclear waste disposal. Finally, AMS microprobes are being developed for the in-situ analysis of stable isotopes in geological samples, semiconductors and other materials. Unfortunately, the use of AMS is limited by the expensive accelerator technology required, but there are several attempts to develop compact AMS spectrometers at low (advances in AMS

Numerical analysis of resonances induced by s wave neutrons in transmission time-of-flight experiments with a computer IBM 7094 II; Methodes d'analyse des resonances induites par les neutrons s dans les experiences de transmission par temps de vol et automatisation de ces methodes sur ordinateur IBM 7094 II

Energy Technology Data Exchange (ETDEWEB)

Corge, Ch. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-01-01

Numerical analysis of transmission resonances induced by s wave neutrons in time-of-flight experiments can be achieved in a fairly automatic way on an IBM 7094/II computer. The involved computations are carried out following a four step scheme: 1 - experimental raw data are processed to obtain the resonant transmissions, 2 - values of experimental quantities for each resonance are derived from the above transmissions, 3 - resonance parameters are determined using a least square method to solve the over determined system obtained by equalling theoretical functions to the correspondent experimental values. Four analysis methods are gathered in the same code, 4 - graphical control of the results is performed. (author) [French] L'automatisation, sur ordinateur IBM 7094/II, de l'analyse des resonances induites par les neutrons s dans les experiences de transmission par temps de vol a ete accomplie en la decomposant selon un schema articule en quatre phases: 1 - le traitement des donnees experimentales brutes pour obtenir les transmissions interfero-resonnantes, 2 - la determination des grandeurs d'analyse a partir des transmissions precedentes, 3 - l'analyse proprement dite des resonances dont les parametres sont obtenus par la resolution d'un systeme surabondant. Quatre methodes d'analyse sont groupees en un meme programme, 4 - la procedure de verification graphique. (auteur)

Contribution to the activation analysis of the rare gases. Contribution to the analysis of carbon monoxide and water vapour in gases (1963); Contribution a l'analyse par activation des gaz rares. Contribution a l'analyse de l'oxyde de carbone et de la vapeur d'eau dans les gaz (1963)

Energy Technology Data Exchange (ETDEWEB)

Diebolt, J [Commisariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1963-07-15

In the present work, we have applied radioactive analysis to the general technique of rare gas separation. This separation is carried out on active charcoal, at constant pressure. The desorption of the gas is caused by an increase in the initial temperature of adsorption. These separations are quantitative and can be confirmed by chemical analysis. The volumes of desorbed gas are measured by radioactive counting. We have also used radioactivation to study the reduction of palladous chloride by carbon monoxide. Since this reduction is quantitative, we can have a knowledge of the mass of palladium reduced by measuring its activity. We have used the property which have organic chlorides of being hydrolysed by water vapour and of liberating hydrochloric acid to study quantitatively the amount of water vapour which a gas contains. The hydrochloric acid formed is measured by activation of the chlorine in the acid. (author) [French] Dans les travaux que nous presentons, nous avons applique l'analyse par radioactivation, a la technique generale de separation des gaz rares. Cette separation est faite sur charbon active, a pression constante. La desorption des gaz est provoquee par une augmentation de la temperature initiale d'adsorption. Ces separations sont quantitatives, et peuvent etre exploitees par l'analyse chimique. Les volumes de gaz dedorbes sont mesures par comptage de la radioactivite. Nous avons egalement utilise la radioactivation pour l'etude de la reduction du chlorure palladeux par l'oxyde de carbone. Cette reduction etant quantitative, nous pouvons connaitre la masse de palladium reduit par la mesure de son activite. Nous avons exploite la propriete que possede un chlorure organique d'etre hydrolise par la vapeur d'eau et de liberer de l'acide chlorhydrique pour etudier quantitativement la vapeur d'eau contenue dans un gaz. L'acide chlorhydrique forme est mesure par l'activation du chlore de l'acide. (auteur)

Phytochemical analyses of Ziziphus jujuba Mill. var. spinosa seed by ultrahigh performance liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry.

Science.gov (United States)

Yang, Bao; Yang, Hongshun; Chen, Feng; Hua, Yanglin; Jiang, Yueming

2013-11-21

Ziziphus jujuba Mill. var. spinosa (Z. jujuba) seeds have attracted much attention within the field of medicine due to their significant effects against disturbances of the central nervous system. Secondary metabolites composition is key to the influence of the pharmaceutical and commercial qualities of this plant. In this work, the phytochemical profile of Z. jujuba seeds was analysed by ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and gas chromatography-mass spectrometry (GC-MS). The UPLC-MS/MS information identified the main secondary metabolites in Z. jujuba seeds, including flavonoid C-glycosides, triterpene acids and unsaturated fatty acids. The leading chemical identified by UPLC-MS/MS was betulinic acid, and oleic acid was the leading volatile from the GC-MS results. All the samples tested showed similar phytochemical profiles, but levels of the chemical compounds varied. Principal component analysis revealed the principal secondary metabolites that could define the differences in quality. It was confirmed that the combination of UPLC-MS/MS and GC-MS was an effective technique to demonstrate the pharmaceutical quality of Z. jujuba seeds.

Use of particles other than neutrons in activation analysis; Emploi de particules autres que les neutrons en analyse par actuation

Energy Technology Data Exchange (ETDEWEB)

Engelmann, Ch [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-15

Nuclear reactions obtained by irradiation in {gamma} Bremsstrahlung, {alpha} particles and protons are particularly suitable for dosing very small traces of light elements. We consider the possibilities presented by activation in {gamma} radiation of 28 MeV maximum energy, mainly for the measurement of C, F, N, O, P and S. Non-destructive methods of analysis for beryllium are described. Under certain conditions they may also be used for other elements such as B, Ca, Li and Na. We give also the results of our first experiments carried out in an attempt to find a method for dosing carbon and oxygen by irradiation in {alpha} particles and protons. For each type of activation the possible types of interference with other nuclear refections are considered. (author) [French] Des reactions nucleaires obtenues par irradiation dans des rayons {gamma} de freinage, des particules {alpha} et des protons, sont particulierement indiquees pour les dosages de traces ultimes de certains elements legers. Nous etudions les possibilites offertes par les activations en rayons {alpha} d'energie maximum 28 MeV, principalement pour les dosages de C, F, N, O, P et S. Des methodes d'analyse non destructives appliquees au beryllium sont decrites. Sous certaines conditions, elles peuvent egalement etre utilisees pour d'autres materiaux comme B, Ca, Li et Na. Nous donnons d'autre part les resultats de nos premieres experiences effectuees pour la mise au point des methodes de dosage du carbone et de l'oxygene par irradiation dans les particules {alpha} et les protons. Pour chaque type d'activation, les possibilites d'interferences avec d'autres reactions nucleaires sont examinees. (auteur)

Paternal age related schizophrenia (PARS): Latent subgroups detected by k-means clustering analysis.

Science.gov (United States)

Lee, Hyejoo; Malaspina, Dolores; Ahn, Hongshik; Perrin, Mary; Opler, Mark G; Kleinhaus, Karine; Harlap, Susan; Goetz, Raymond; Antonius, Daniel

2011-05-01

Paternal age related schizophrenia (PARS) has been proposed as a subgroup of schizophrenia with distinct etiology, pathophysiology and symptoms. This study uses a k-means clustering analysis approach to generate hypotheses about differences between PARS and other cases of schizophrenia. We studied PARS (operationally defined as not having any family history of schizophrenia among first and second-degree relatives and fathers' age at birth ≥ 35 years) in a series of schizophrenia cases recruited from a research unit. Data were available on demographic variables, symptoms (Positive and Negative Syndrome Scale; PANSS), cognitive tests (Wechsler Adult Intelligence Scale-Revised; WAIS-R) and olfaction (University of Pennsylvania Smell Identification Test; UPSIT). We conducted a series of k-means clustering analyses to identify clusters of cases containing high concentrations of PARS. Two analyses generated clusters with high concentrations of PARS cases. The first analysis (N=136; PARS=34) revealed a cluster containing 83% PARS cases, in which the patients showed a significant discrepancy between verbal and performance intelligence. The mean paternal and maternal ages were 41 and 33, respectively. The second analysis (N=123; PARS=30) revealed a cluster containing 71% PARS cases, of which 93% were females; the mean age of onset of psychosis, at 17.2, was significantly early. These results strengthen the evidence that PARS cases differ from other patients with schizophrenia. Hypothesis-generating findings suggest that features of PARS may include a discrepancy between verbal and performance intelligence, and in females, an early age of onset. These findings provide a rationale for separating these phenotypes from others in future clinical, genetic and pathophysiologic studies of schizophrenia and in considering responses to treatment. Copyright © 2011 Elsevier B.V. All rights reserved.

Contribution to the analysis of light elements using x fluorescence excited by radio-elements; Contribution a l'analyse des elements legers par fluorescence x excitee au moyen de radioelements

Energy Technology Data Exchange (ETDEWEB)

Robert, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-01

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, {beta} and {alpha} 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{sub {alpha}} lines of 3. period elements excited by {sup 55}Fe, {sup 3}H/Zr and {sup 210}Po sources; for the 2. period the K{sub {alpha}} spectra of carbon and of fluorine excited by the {alpha} particles of {sup 210}Po. (author) [French] Afin d'etudier les possibilites d'emploi de sources radioactives a l'analyse par fluorescence X des elements legers, on presente apres rappel de notions generales sur la fluorescence X, le principe de l'excitation de ce phenomene par emission X, {beta}, {alpha} de radioelements. Le fonctionnement et l'utilisation du compteur proportionnel a gaz a la detection du rayonnement X est developpe. Un dispositif permettant l'analyse des elements des 2eme et 3eme periodes de la classification de Mendeleev est etudie. Il permet l'excitation de la fluorescence par source radioactive emettrice de rayons X ou de particules {alpha}; le rayonnement X de fluorescence penetre dans un compteur proportionnel depourvu de fenetre, ceci est rendu possible en creant un champ electrique auxiliaire au voisinage de l'echantillon. On definit une pression du gaz de detection pour un rendement de detection maximal

Directed and persistent movement arises from mechanochemistry of the ParA/ParB system.

Science.gov (United States)

Hu, Longhua; Vecchiarelli, Anthony G; Mizuuchi, Kiyoshi; Neuman, Keir C; Liu, Jian

2015-12-22

The segregation of DNA before cell division is essential for faithful genetic inheritance. In many bacteria, segregation of low-copy number plasmids involves an active partition system composed of a nonspecific DNA-binding ATPase, ParA, and its stimulator protein ParB. The ParA/ParB system drives directed and persistent movement of DNA cargo both in vivo and in vitro. Filament-based models akin to actin/microtubule-driven motility were proposed for plasmid segregation mediated by ParA. Recent experiments challenge this view and suggest that ParA/ParB system motility is driven by a diffusion ratchet mechanism in which ParB-coated plasmid both creates and follows a ParA gradient on the nucleoid surface. However, the detailed mechanism of ParA/ParB-mediated directed and persistent movement remains unknown. Here, we develop a theoretical model describing ParA/ParB-mediated motility. We show that the ParA/ParB system can work as a Brownian ratchet, which effectively couples the ATPase-dependent cycling of ParA-nucleoid affinity to the motion of the ParB-bound cargo. Paradoxically, this resulting processive motion relies on quenching diffusive plasmid motion through a large number of transient ParA/ParB-mediated tethers to the nucleoid surface. Our work thus sheds light on an emergent phenomenon in which nonmotor proteins work collectively via mechanochemical coupling to propel cargos-an ingenious solution shaped by evolution to cope with the lack of processive motor proteins in bacteria.

Contribution to the analysis of light elements using x fluorescence excited by radio-elements; Contribution a l'analyse des elements legers par fluorescence x excitee au moyen de radioelements

Energy Technology Data Exchange (ETDEWEB)

Robert, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-01

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, {beta} and {alpha} 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{sub {alpha}} lines of 3. period elements excited by {sup 55}Fe, {sup 3}H/Zr and {sup 210}Po sources; for the 2. period the K{sub {alpha}} spectra of carbon and of fluorine excited by the {alpha} particles of {sup 210}Po. (author) [French] Afin d'etudier les possibilites d'emploi de sources radioactives a l'analyse par fluorescence X des elements legers, on presente apres rappel de notions generales sur la fluorescence X, le principe de l'excitation de ce phenomene par emission X, {beta}, {alpha} de radioelements. Le fonctionnement et l'utilisation du compteur proportionnel a gaz a la detection du rayonnement X est developpe. Un dispositif permettant l'analyse des elements des 2eme et 3eme periodes de la classification de Mendeleev est etudie. Il permet l'excitation de la fluorescence par source radioactive emettrice de rayons X ou de particules {alpha}; le rayonnement X de fluorescence penetre dans un compteur proportionnel depourvu de fenetre, ceci est rendu possible en creant un champ electrique auxiliaire au voisinage de l'echantillon. On definit une pression du gaz de detection

[Ambroise Paré, his death and his historians].

Science.gov (United States)

Dumaître, P

2001-01-01

Ambroise Paré died December the 20th., 1590. What happened after his death and what are we knowing about his life? Never forgotten, though a lack of care, we were waiting till the XIXth. century to get recollection upon a subject sustained only by accounts of his travels. After Percy, a surgeon who tried to write Paré's biography through the "Biographie universelle ancienne et moderne, de Michaud (1822)" and some second rank authors, Malgaigne is the first who inside a printing of the "Oeuvres complétes de Paré (1840-41)" has a fine look upon the question, though his work is incomplete and allows many mistakes. Doctors Chéreau and Jal, an historian, analysing civil status records, gave new information enlarged by doctors Le Paulmier, Turner and the U.S. native Janet Doe.

Dynamics of urokinase receptor interaction with Peptide antagonists studied by amide hydrogen exchange and mass spectrometry

DEFF Research Database (Denmark)

Jørgensen, Thomas J D; Gårdsvoll, Henrik; Danø, Keld

2004-01-01

Using amide hydrogen exchange combined with electrospray ionization mass spectrometry, we have in this study determined the number of amide hydrogens on several peptides that become solvent-inaccessible as a result of their high-affinity interaction with the urokinase-type plasminogen activator...... receptor (uPAR). These experiments reveal that at least six out of eight amide hydrogens in a synthetic nine-mer peptide antagonist (AE105) become sequestered upon engagement in uPAR binding. Various uPAR mutants with decreased affinity for this peptide antagonist gave similar results, thereby indicating...... that deletion of the favorable interactions involving the side chains of these residues in uPAR does not affect the number of hydrogen bonds established by the main chain of the peptide ligand. The isolated growth factor-like domain (GFD) of the cognate serine protease ligand for uPAR showed 11 protected amide...

Atomic mass spectrometry

International Nuclear Information System (INIS)

Sanz-Medel, A.

1997-01-01

The elemental inorganic analysis seems to be dominated today by techniques based on atomic spectrometry. After an evaluation of advantages and limitations of using mass analysers (ion detectors) versus conventional photomultipliers (photon detector) a brief review of the more popular techniques of the emerging Atomic Mass spectrometry is carried out. Their huge potential for inorganic trace analysis is such that in the future we could well witness how this end of the century and millennium marked the fall of the photons empire in Analytical Atomic Spectrometry. (Author)

Croissance epitaxiale de GaAs sur substrats de Ge par epitaxie par faisceaux chimiques

Science.gov (United States)

Belanger, Simon

La situation energetique et les enjeux environnementaux auxquels la societe est confrontee entrainent un interet grandissant pour la production d'electricite a partir de l'energie solaire. Parmi les technologies actuellement disponibles, la filiere du photovoltaique a concentrateur solaire (CPV pour concentrator photovoltaics) possede un rendement superieur et mi potentiel interessant a condition que ses couts de production soient competitifs. La methode d'epitaxie par faisceaux chimiques (CBE pour chemical beam epitaxy) possede plusieurs caracteristiques qui la rendent interessante pour la production a grande echelle de cellules photovoltaiques a jonctions multiples a base de semi-conducteurs III-V. Ce type de cellule possede la meilleure efficacite atteinte a ce jour et est utilise sur les satellites et les systemes photovoltaiques a concentrateur solaire (CPV) les plus efficaces. Une des principales forces de la technique CBE se trouve dans son potentiel d'efficacite d'utilisation des materiaux source qui est superieur a celui de la technique d'epitaxie qui est couramment utilisee pour la production a grande echelle de ces cellules. Ce memoire de maitrise presente les travaux effectues dans le but d'evaluer le potentiel de la technique CBE pour realiser la croissance de couches de GaAs sur des substrats de Ge. Cette croissance constitue la premiere etape de fabrication de nombreux modeles de cellules solaires a haute performance decrites plus haut. La realisation de ce projet a necessite le developpement d'un procede de preparation de surface pour les substrats de germanium, la realisation de nombreuses sceances de croissance epitaxiale et la caracterisation des materiaux obtenus par microscopie optique, microscopie a force atomique (AFM), diffraction des rayons-X a haute resolution (HRXRD), microscopie electronique a transmission (TEM), photoluminescence a basse temperature (LTPL) et spectrometrie de masse des ions secondaires (SIMS). Les experiences ont permis

FooPar

DEFF Research Database (Denmark)

Hargreaves, F. P.; Merkle, D.

2013-01-01

We present FooPar, an extension for highly efficient Parallel Computing in the multi-paradigm programming language Scala. Scala offers concise and clean syntax and integrates functional programming features. Our framework FooPar combines these features with parallel computing techniques. Foo......, results based on a empirical analysis on two supercomputers are given. We achieve close-to-optimal performance wrt. theoretical peak performance. Based on this result we conclude that FooPar allows programmers to fully access Scalas design features without suffering from performance drops when compared...

An accessible, scalable ecosystem for enabling and sharing diverse mass spectrometry imaging analyses.

Energy Technology Data Exchange (ETDEWEB)

Fischer, CR; Ruebel, O; Bowen, BP

2016-01-01

Mass spectrometry imaging (MSI) is used in an increasing number of biological applications. Typical MSI datasets contain unique, high-resolution mass spectra from tens of thousands of spatial locations, resulting in raw data sizes of tens of gigabytes per sample. In this paper, we review technical progress that is enabling new biological applications and that is driving an increase in the complexity and size of MSI data. Handling such data often requires specialized computational infrastructure, software, and expertise. OpenMSI, our recently described platform, makes it easy to explore and share MSI datasets via the web - even when larger than 50 GB. Here we describe the integration of OpenMSI with IPython notebooks for transparent, sharable, and replicable MSI research. An advantage of this approach is that users do not have to share raw data along with analyses; instead, data is retrieved via OpenMSI's web API. The IPython notebook interface provides a low-barrier entry point for data manipulation that is accessible for scientists without extensive computational training. Via these notebooks, analyses can be easily shared without requiring any data movement. We provide example notebooks for several common MSI analysis types including data normalization, plotting, clustering, and classification, and image registration.

Optimization of Reversed-Phase Peptide Liquid Chromatography Ultraviolet Mass Spectrometry Analyses Using an Automated Blending Methodology

Science.gov (United States)

Chakraborty, Asish B.; Berger, Scott J.

2005-01-01

The balance between chromatographic performance and mass spectrometric response has been evaluated using an automated series of experiments where separations are produced by the real-time automated blending of water with organic and acidic modifiers. In this work, the concentration effects of two acidic modifiers (formic acid and trifluoroacetic acid) were studied on the separation selectivity, ultraviolet, and mass spectrometry detector response, using a complex peptide mixture. Peptide retention selectivity differences were apparent between the two modifiers, and under the conditions studied, trifluoroacetic acid produced slightly narrower (more concentrated) peaks, but significantly higher electrospray mass spectrometry suppression. Trifluoroacetic acid suppression of electrospray signal and influence on peptide retention and selectivity was dominant when mixtures of the two modifiers were analyzed. Our experimental results indicate that in analyses where the analyzed components are roughly equimolar (e.g., a peptide map of a recombinant protein), the selectivity of peptide separations can be optimized by choice and concentration of acidic modifier, without compromising the ability to obtain effective sequence coverage of a protein. In some cases, these selectivity differences were explored further, and a rational basis for differentiating acidic modifier effects from the underlying peptide sequences is described. PMID:16522853

New trends in nuclear spectrometry

International Nuclear Information System (INIS)

Westmeier, W.; Siemon, K.

2013-01-01

An overview on the status and function of current spectrometry hardware, of detectors having energy-dispersive (spectrometric) properties as well as of the latest developments in quantitative spectrometry software is presented. Making extensive use of modern computing power, new strategies in high-precision spectrum analysis have been developed which enhance the quality of results and also open new fields of spectrometric applications. Three principles have been newly introduced to spectrum analysis software: -use no approximations in modelling (Physics, no numerology) -apply all available models to find a solution (Fuzzy Logic) -repeat complete analyses for iterative improvement (Learn from results). -- Highlights: ► We present an overview of MCA hardware and detectors for nuclear spectrometry. ► Physics-oriented descriptions, Fuzzy Logic and multiple repetitive analyses lead to improved results in spectrum analysis. ► New strategies allow the successful deconvolution of spectra that could not be analysed before

The Spatial Distribution of Alkaloids in Psychotria prunifolia (Kunth) Steyerm and Palicourea coriacea (Cham.) K. Schum Leaves Analysed by Desorption Electrospray Ionisation Mass Spectrometry Imaging

DEFF Research Database (Denmark)

Kato, Lucilia; Moraes, Aline Pereira; de Oliveira, Cecília Maria Alves

2018-01-01

INTRODUCTION: Species of the genera Psychotria and Palicourea are sources of indole alkaloids, however, the distribution of alkaloids within the plants is not known. Analysing the spatial distribution using desorption electrospray ionisation mass spectrometry imaging (DESI-MSI) has become...... analyses. METHODOLOGY: Based upon previous structure elucidation studies, four alkaloids targeted in this study were identified using high resolution mass spectrometry by direct infusion of plant extracts, and their distributions were imaged by DESI-MSI via tissue imprints on a porous Teflon surface....... Relative quantitation of the four alkaloids was obtained by HPLC-MS/MS analysis performed using multiple-reaction monitoring (MRM) mode on a triple quadrupole mass spectrometer. RESULTS: Alkaloids showed distinct distributions on the leaf surfaces. Prunifoleine was mainly present in the midrib, while 10...

Ninth ISMAS workshop on mass spectrometry

International Nuclear Information System (INIS)

Aggarwal, S.K.

2000-12-01

Mass spectrometry has wide-ranging applications in such diverse areas as nuclear industry, agriculture, drugs, environment, petroleum and lentils. There is an urgent need to absorb and assimilate state-of-the-art technological developments in the field. Emerging trends in atomic mass spectrometry, advances in organic mass spectrometry, qualitative and quantitative analyses by mass spectrometry and mass spectrometry in oceanography are some of the areas that need to be expeditiously examined and are covered in this volume. Papers relevant to INIS are indexed separately

Ion Mobility Spectrometry-Mass Spectrometry Coupled with Gas-Phase Hydrogen/Deuterium Exchange for Metabolomics Analyses

Science.gov (United States)

Maleki, Hossein; Karanji, Ahmad K.; Majuta, Sandra; Maurer, Megan M.; Valentine, Stephen J.

2018-02-01

Ion mobility spectrometry-mass spectrometry (IMS-MS) in combination with gas-phase hydrogen/deuterium exchange (HDX) and collision-induced dissociation (CID) is evaluated as an analytical method for small-molecule standard and mixture characterization. Experiments show that compound ions exhibit unique HDX reactivities that can be used to distinguish different species. Additionally, it is shown that gas-phase HDX kinetics can be exploited to provide even further distinguishing capabilities by using different partial pressures of reagent gas. The relative HDX reactivity of a wide variety of molecules is discussed in light of the various molecular structures. Additionally, hydrogen accessibility scoring (HAS) and HDX kinetics modeling of candidate ( in silico) ion structures is utilized to estimate the relative ion conformer populations giving rise to specific HDX behavior. These data interpretation methods are discussed with a focus on developing predictive tools for HDX behavior. Finally, an example is provided in which ion mobility information is supplemented with HDX reactivity data to aid identification efforts of compounds in a metabolite extract.

ParA and ParB coordinate chromosome segregation with cell elongation and division during Streptomyces sporulation

Science.gov (United States)

Donczew, Magdalena; Mackiewicz, Paweł; Wróbel, Agnieszka; Flärdh, Klas; Zakrzewska-Czerwińska, Jolanta

2016-01-01

In unicellular bacteria, the ParA and ParB proteins segregate chromosomes and coordinate this process with cell division and chromosome replication. During sporulation of mycelial Streptomyces, ParA and ParB uniformly distribute multiple chromosomes along the filamentous sporogenic hyphal compartment, which then differentiates into a chain of unigenomic spores. However, chromosome segregation must be coordinated with cell elongation and multiple divisions. Here, we addressed the question of whether ParA and ParB are involved in the synchronization of cell-cycle processes during sporulation in Streptomyces. To answer this question, we used time-lapse microscopy, which allows the monitoring of growth and division of single sporogenic hyphae. We showed that sporogenic hyphae stop extending at the time of ParA accumulation and Z-ring formation. We demonstrated that both ParA and ParB affect the rate of hyphal extension. Additionally, we showed that ParA promotes the formation of massive nucleoprotein complexes by ParB. We also showed that FtsZ ring assembly is affected by the ParB protein and/or unsegregated DNA. Our results indicate the existence of a checkpoint between the extension and septation of sporogenic hyphae that involves the ParA and ParB proteins. PMID:27248800

Par Pond water balance

International Nuclear Information System (INIS)

Hiergesell, R.A.; Dixon, K.L.

1996-06-01

A water budget for the Par Pond hydrologic system was established in order to estimate the rate of groundwater influx to Par Pond. This estimate will be used in modeling exercises to predict Par Pond reservoir elevation and spillway discharge in the scenario where Savannah River water is no longer pumped and discharged into Par Pond. The principal of conservation of mass was used to develop the water budget, where water inflow was set equal to water outflow. Components of the water budget were identified, and the flux associated with each was determined. The water budget was considered balanced when inflow and outflow summed to zero. The results of this study suggest that Par Pond gains water from the groundwater system in the upper reaches of the reservoir, but looses water to the groundwater system near the dam. The rate of flux of groundwater from the water table aquifer into Par Pond was determined to be 13 cfs. The rate of flux from Par Pond to the water table aquifer near the dam was determined to be 7 cfs

uPAR Expression Pattern in Patients with Urothelial Carcinoma of the Bladder

DEFF Research Database (Denmark)

Dohn, Line Hammer; Pappot, Helle; Iversen, Benedikte Richter

2015-01-01

The objective of the present study was to confirm the expression and localisation pattern of the urokinase-type plasminogen activator receptor (uPAR) focusing on its possible clinical relevance in patients with urothelial neoplasia of the bladder. uPAR is a central molecule in tissue remodelling...... during cancer invasion and metastasis and is an established prognostic marker in various cancer diseases other than bladder cancer. Formalin-fixed and paraffin-embedded tumour-tissue blocks from 186 patients treated with radical cystectomy were analysed. uPAR expression was scored as either negative...... or positive as well as by the actual score. Separate scores were obtained for cancer cells, macrophages and myofibroblasts at the invasive front and in tumour core. We were able to confirm, in an independent patient cohort, the tissue expression and localisation pattern of uPAR as investigated...

Brief communication: Population variation in human maxillary premolar accessory ridges (MxPAR).

Science.gov (United States)

Burnett, Scott E; Hawkey, Diane E; Turner, Christy G

2010-02-01

The purpose of this brief communication is to report the results of an analysis of maxillary premolar accessory ridges (MxPAR), a common but understudied accessory ridge that may occur both mesial and distal to the central ridge of the buccal cusp of upper premolars. We developed a new five-grade scoring plaque to better categorize MxPAR variation. Subsequently, we conducted a population analysis of MxPAR frequency in 749 dental casts of South African Indian, American Chinese, Alaskan Eskimo, Tohono O'odham (Papago), Akimel O'odham (Pima), Solomon Islander, South African Bantu, and both American and South African Whites. Northeast Asian and Asian-derived populations exhibited the highest MxPAR frequencies while Indo-European samples (South African Indians, American and South African Whites) exhibited relatively low frequencies. The Solomon Islanders and South African Bantu samples exhibited intermediate frequencies. Our analysis indicates that statistically significant differences in MxPAR frequency exist between major geographic populations. As a result, the MxPAR plaque has now been added to the Arizona State University Dental Anthropology System, an important contribution as maxillary premolar traits are underrepresented in analyses of dental morphology. 2009 Wiley-Liss, Inc.

suPAR

DEFF Research Database (Denmark)

Hodges, Gethin W; Bang, Casper N; Wachtell, Kristian

2015-01-01

The fundamental role of inflammation in cardiovascular disease (CVD) has prompted interest in numerous biomarkers that detect subclinical levels of inflammation. Soluble urokinase plasminogen activator receptor (suPAR) is a novel biomarker that correlates significantly with cardiovascular events ...... comprehensive review of suPAR in CVD and explore its function and usefulness in predicting cardiovascular events....

C9.A/14 steelwork joints de poutres par plaque frontale : assemblages par gousset

CERN Document Server

2015-01-01

Les Tables de résistances ultimes des assemblages boulonnés par plaque frontale et par gousset, complétées par une description des modèles de calcul et des exemples d’application, ont pour but de faciliter la tâche de l'ingénieur et du constructeur. Cette première partie C9.A/14 contient les chapitres suivants: - Joints de poutres par plaque frontale en acier S235 et S355 - Assemblages par gousset en acier S235 et S355 Les Tables contiennent des données relatives à la géométrie ainsi que les valeurs de calcul correspondantes des résistances ultimes des assemblages ; elles remplacent le chapitre « Assemblages par plaques frontales et boulons HR » des anciennes Tables C9.1 de 1983 / 2002. Le calcul de ces assemblages par plaque frontale est basé sur les hypothèses du modèle de la méthode des composants décrite dans la norme SN EN 1993-1-8. Les vérifications sont effectuées selon la norme SIA 263:2013. Les assemblages par gousset remplacent les assemblages par double cornière, (telle...

Development of SI-traceable C-peptide certified reference material NMIJ CRM 6901-a using isotope-dilution mass spectrometry-based amino acid analyses.

Science.gov (United States)

Kinumi, Tomoya; Goto, Mari; Eyama, Sakae; Kato, Megumi; Kasama, Takeshi; Takatsu, Akiko

2012-07-01

A certified reference material (CRM) is a higher-order calibration material used to enable a traceable analysis. This paper describes the development of a C-peptide CRM (NMIJ CRM 6901-a) by the National Metrology Institute of Japan using two independent methods for amino acid analysis based on isotope-dilution mass spectrometry. C-peptide is a 31-mer peptide that is utilized for the evaluation of β-cell function in the pancreas in clinical testing. This CRM is a lyophilized synthetic peptide having the human C-peptide sequence, and contains deamidated and pyroglutamylated forms of C-peptide. By adding water (1.00 ± 0.01) g into the vial containing the CRM, the C-peptide solution in 10 mM phosphate buffer saline (pH 6.6) is reconstituted. We assigned two certified values that represent the concentrations of total C-peptide (mixture of C-peptide, deamidated C-peptide, and pyroglutamylated C-peptide) and C-peptide. The certified concentration of total C-peptide was determined by two amino acid analyses using pre-column derivatization liquid chromatography-mass spectrometry and hydrophilic chromatography-mass spectrometry following acid hydrolysis. The certified concentration of C-peptide was determined by multiplying the concentration of total C-peptide by the ratio of the relative area of C-peptide to that of the total C-peptide measured by liquid chromatography. The certified value of C-peptide (80.7 ± 5.0) mg/L represents the concentration of the specific entity of C-peptide; on the other hand, the certified value of total C-peptide, (81.7 ± 5.1) mg/L can be used for analyses that does not differentiate deamidated and pyroglutamylated C-peptide from C-peptide itself, such as amino acid analyses and immunochemical assays.

Estuarine morphometry governs optically active substances, Kd(PAR) and beam attenuation

DEFF Research Database (Denmark)

Lund-Hansen, L. C.; Nielsen, J. M.; Blüthgen, J.

2013-01-01

estuaries using OACs as input parameters. It is concluded that there are no large differences in OAC concentrations between the two estuaries. The spatial distributions of OACs and optical properties were significantly different and governed by the estuary morphometry, i.e. a power distribution......°N) at high discharges. The major difference was the spatial distribution of the optical properties against distance, best described by significant power functions in the ria, compared to significant linear functions in the coastal plain. It was hypothesized that estuarine morphometry could explain...... this spatial distribution. Partition and multiple regression analyses showed that Chl-a governed Kd(PAR) and beam attenuation coefficient in both estuaries. Significant, high correlations were obtained by multiple regression analyses in the estimation of Kd(PAR) and beam attenuation coefficients in the two...

Dosage of cesium 137 in radioactive wastes by the application of sodium tetraphenylborate; Dosage du cesium 137 dans les effluents radioactifs par le tetraphenylborate de sodium

Energy Technology Data Exchange (ETDEWEB)

Testemale, G; Girault, J [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1967-07-01

A simple technique of the dosage of {sup 137}Cs has been developed. The technique consists in the formation of cesium tetraphenyl borate, followed by a double extraction with isoamyl acetate, and washing of the organic phase. The counting of known parts of the cesium solution assaying of its purity by {gamma} spectrometry enable the determination of the {sup 137}Cs. The yield is about 98 per cent. (authors) [French] Une technique simple du dosage du {sup 137}Cs a ete mise au point. Elle consiste en une double extraction du tetraphenylborate de cesium forme par l'acetate d'isoamyle suivie d'un lavage de la phase organique. Des comptages sur des parties aliquotes de la solution de cesium et un controle de purete par spectrometrie {gamma} permettent la determination de cet element. Rendement: environ 98 pour cent. (auteurs)

Traitement De La Peripneumonie Contagieuse Bovine Par L ...

African Journals Online (AJOL)

Traitement De La Peripneumonie Contagieuse Bovine Par L'oxyteTracycline Longe Action Et Transmission Experimentale de la Maladie A Partir de Bovins Traites. ... Tous les 14 animaux ont séroconverti et l'analyse post-mortem a montré la présence des lésions chroniques dont des séquestres pulmonaires chez 4 d'entre ...

Composition and mechanisms analysis of aromatic telechelic oligomers by mass spectroscopy; Analyse de la composition et de mecanismes de polymerisation d`oligomeres telecheliques aromatiques par spectrometrie de masse

Energy Technology Data Exchange (ETDEWEB)

Damerval, V.

1997-10-22

The aim of this work was to apply mass spectrometry, on the one hand to the characterization of telechelic oligo-imides with oxazoline and lactane end-caps and, on the other hand to the determination of the thermal reticulation mechanism of nadimides. First bis-oxazoline and buslactane end-capped, oligomers used to form blocks copolymers were studied by liquid secondary ion mass spectroscopy (LSIMS) and Matrix-assisted laser desorption ionization time of flight spectroscopy (MALDI-TOF). An acetamide end-cap by-product was detected. Then the analysis was modified to avoid the formation of this by-product which was unable to copolymerize. Secondly, to circumvent the experimental difficulties related to crosslinked networks, the study of the thermal polymerization of nadimides was performed ones (LSIMS, electroscopy, MALDI-TOF) led to the determination of the polynadimide structure. Thanks to MS/MS studies the nature of the linkages and the structure of the end-caps were established. Finally, this work evidenced the opportunity to use mass spectrometry to analyze synthetic polymers. (author) 222 refs.

Parálisis cerebral :

OpenAIRE

Cabrero Izquierdo, María del Carmen

2012-01-01

Se aborda el tema de la parálisis cerebral definiendo qué es, clasificando los tipos de parálisis dependiendo de la afectación y las características principales. Se explican algunos de sus tratamientos, se dan sistemas alternativos y/o aumentativos de comunicación para un alumno con PC (parálisis cerebral).

Migration-Velocity Analysis for Ti and Orthorhombic Background Media Analyse de vitesse par migration dans les cas de milieux environnantsTI et orthorhombiques

Directory of Open Access Journals (Sweden)

Ikelle L. T.

2006-12-01

migration instead of using directly. Il est essentiel de connaître le modèle de vitesse du milieu environnant pour effectuer la description précise du réservoir que l'on veut obtenir par imagerie et par inversion. Les méthodes conventionnelles permettant de reconstituer le modèle de vitesse de fond, telles que les méthodes de vitesse migratoire, supposent souvent une sous-surface isotrope et peuvent donner des descriptions de réservoirs manquant de précisions lorsque la sous-surface contient des formations de roches anisotropes. Nous généralisons ici le concept de vitesse migratoire en permettant à la vitesse de fond d'être transversalement isotrope (TI par rapport à l'axe vertical ou orthorhombique. Cette méthode consiste à scanner différents modèles de vitesse anisotropes à l'aide d'une migration à décalage de phases et de sélectionner des paramètres anisotropes sur la base des variations d'amplitude des résultats migrés (analyse par focalisation. Sachant que le modèle de vitesse de fond anisotrope est généralement décrit par plusieurs coefficients d'élasticité, il importe d'adopter une procédure de scannage efficace. Nous avons choisi de travailler sur des sections azimutales communes. Pour une section azimutale commune donnée, nous avons effectué une analyse continue de deux paramètres : la vitesse normale de déplacement et le paramètre anisotrope connu sous le nom d'anellipticité. Ces deux balayages nous permettent de reconstituer un modèle de vitesse azimutalement isotrope. L'opération est ensuite répétée pour différentes sections azimutales communes ; chacune d'entre elles donne un nouveau modèle de vitesse azimutalement isotrope si le support est azimutalement anisotrope. Le nombre de sections azimutales communes, et par conséquent le nombre de modèles de vitesse azimutalement isotropes nécessaires pour reconstituer un modèle de vitesse azimutalement anisotrope, dépend du type de symétries. Par exemple, il faut

Novel role for proteinase-activated receptor 2 (PAR2) in membrane trafficking of proteinase-activated receptor 4 (PAR4).

Science.gov (United States)

Cunningham, Margaret R; McIntosh, Kathryn A; Pediani, John D; Robben, Joris; Cooke, Alexandra E; Nilsson, Mary; Gould, Gwyn W; Mundell, Stuart; Milligan, Graeme; Plevin, Robin

2012-05-11

Proteinase-activated receptors 4 (PAR(4)) is a class A G protein-coupled receptor (GPCR) recognized through the ability of serine proteases such as thrombin and trypsin to mediate receptor activation. Due to the irreversible nature of activation, a fresh supply of receptor is required to be mobilized to the cell surface for responsiveness to agonist to be sustained. Unlike other PAR subtypes, the mechanisms regulating receptor trafficking of PAR(4) remain unknown. Here, we report novel features of the intracellular trafficking of PAR(4) to the plasma membrane. PAR(4) was poorly expressed at the plasma membrane and largely retained in the endoplasmic reticulum (ER) in a complex with the COPI protein subunit β-COP1. Analysis of the PAR(4) protein sequence identified an arginine-based (RXR) ER retention sequence located within intracellular loop-2 (R(183)AR → A(183)AA), mutation of which allowed efficient membrane delivery of PAR(4). Interestingly, co-expression with PAR(2) facilitated plasma membrane delivery of PAR(4), an effect produced through disruption of β-COP1 binding and facilitation of interaction with the chaperone protein 14-3-3ζ. Intermolecular FRET studies confirmed heterodimerization between PAR(2) and PAR(4). PAR(2) also enhanced glycosylation of PAR(4) and activation of PAR(4) signaling. Our results identify a novel regulatory role for PAR(2) in the anterograde traffic of PAR(4). PAR(2) was shown to both facilitate and abrogate protein interactions with PAR(4), impacting upon receptor localization and cell signal transduction. This work is likely to impact markedly upon the understanding of the receptor pharmacology of PAR(4) in normal physiology and disease.

Examining relational empowerment for elementary school students in a yPAR program.

Science.gov (United States)

Langhout, Regina Day; Collins, Charles; Ellison, Erin Rose

2014-06-01

This paper joins relational empowerment, youth empowerment, and Bridging Multiple Worlds frameworks to examine forms of relational empowerment for children in two intermediary institutions-school and a youth participatory action research after-school program (yPAR ASP). Participants were twelve children, most of whom were Latina/o and from im/migrant families, enrolled in a yPAR ASP for 2 years. A mixed-method approach was utilized; we analyzed children's interviews, self-defined goals, and their social networks to examine their experiences of relational empowerment. We conclude that children experienced each of the five relational empowerment factors-collaborative competence, bridging social divisions, facilitating others' empowerment, mobilizing networks, and passing on a legacy-in the yPAR ASP setting, and some factors in school. These experiences, however, were more pronounced in the yPAR ASP setting. Additionally, social network analyses revealed that a small but meaningful percentage of actors bridged worlds, especially home and family, but by year 2, also school and the yPAR ASP. Finally, most helpers for school-based goals came from school, but a sizable number came from family, friends, and home worlds, and by year 2, also came from the yPAR ASP. Implications range from theoretical to methodological development, including the use of social network analysis as a tool to descriptively examine relational power in context.

Analytical methods used by the geochemical section: water; Methodes d'analyses utilisees par la section de geochimie: les eaux

Energy Technology Data Exchange (ETDEWEB)

Berthollet, P; Cavalier, G [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1971-07-01

The authors describe the analytical methods used by the C.E.A. Geochemical Section to determine the chemical composition of natural waters encountered during the prospecting of uraniferous deposits or in the course of mining operations. Because of the diversity of the samples and the different items of information requested, methods were selected and adapted to answer to the demands peculiar to mining research. Methods and know-how concerning the quantitative analysis of natural water to find out the concentration of the following chemicals are reviewed: carbonates and bicarbonates, calcium, magnesium, chlorides, sodium and potassium, sulfates, nitrates, silica, phosphates, iron, manganese, aluminium, fluorides, dissolved oxygen, CO{sub 2}, SH{sub 2} and sulphur, and uranium. (authors) [French] Les auteurs decrivent les methodes d'analyses utilisees par la Section de Geochimie du C.E.A., pour la determination de la composition chimique des eaux naturelles rencontrees au cours de prospections de gites uraniferes ou de travaux miniers. La diversite des echantillons et les differents renseignements demandes a l'analyse les ont conduit a selectionner et a adapter des methodes afin qu'elles repondent aux exigences particulieres de la recherche miniere. Les methodes concernant le dosage dans les eaux superficielles et eaux souterraines des elements qui suivent sont presentees : carbonates and bicarbonates, calcium, magnesium, chlorures, sodium et potassium, sulfates, nitrates, silice, phosphates, fer ferreus et ferrique, manganese, aluminium, fluorures, oxygene dissous, CO{sub 2} libre, SH{sub 2} et soufre total, et uranium. (auteurs)

Spectrometry techniques for radioactivity measurements

International Nuclear Information System (INIS)

Anilkumar, S.

2016-01-01

The energy of the radiation emission following the nuclear decay is unique and the characteristic of the radio nuclide which undergoes decay. Thus measurement of the energy of the radiation offers a method of identifying the radio nuclides. The prime requirement of the energy measurement is a suitable detector which shows response proportional to the energy of the radiation rather than the presence of the radiation. The response from such detectors are suitably processed and distributed with respect to the signal strength which is proportional to incident energy. This distribution is normally referred as energy spectrum and is recorded in the multichannel analyser. The measurement of energy and intensity of radiation from the spectrum is called radiation spectrometry. Thus the radiation spectrometry allows the identification and quantification of radioactive isotopes in variety of matrices. The radiation spectrometry has now become a popular radioanalytical technique in wide area of nuclear fuel cycle programs. The popular spectrometry techniques commonly used for the radioactivity measurement and analysis are Alpha spectrometry, Gamma ray spectrometry and Beta spectrometry

Radionuclide content of simulated and fully radioactive SRLLL waste glasses: comparison of results from ICP-MS, gamma spectrometry and alpha spectrometry

International Nuclear Information System (INIS)

Wolf, S.F.; Bates, J.K.

1995-01-01

We have measured the transuranic content of two transuranic=doped, simulated waste glasses, using inductively coupled plasma-mass spectrometry (ICP-MS), γ-spectrometry, and α-spectrometry. Average concentrations measured by each technique were within ± 10% of the as-doped concentrations. We also report the transuranic content of three fully radioactive SRL waste glasses that were determined using γ- and α-spectrometry measurements to deconvolute isobaric interferences present in the ICP-MS analyses

Microhabitats utilisés par les alevins 0+ d'une communauté de cyprins rhéophiles : analyse de l'évolution de la communauté et des densités de population

Directory of Open Access Journals (Sweden)

BARAS E.

1995-04-01

Full Text Available L'évolution de l'occupation des microhabitats par les alevins de la communauté de cyprins rhéophiles de l'Ourthe a été étudiée au cours de l'été et de l'automne 1994 par échantillonnage ponctuel d'abondance (électrodes fixes prépositionnées, courant continu. 16155 poissons (10-75 mm appartenant à 15 espèces ont été recensés sur 78 sites d'échantillonnage de 2 m2 . Les espèces les plus représentées étaient Leuciscus cephalus, Leuciscus leuciscus et Chondrostoma nasus (respectivement 43,6 %, 20,7 % et 16,7 % des captures estivales. L'analyse factorielle des correspondances d'une matrice site x (espèce x taille met en évidence une subdivision progressive de la communauté au cours de l'été en espèces d'eau vive (B. barbus et L. leuciscus et d'eau lente, davantage associées à un couvert végétal (L. cephalus et C. nasus. La densité maximale observée (fin juin est de 1500 alevins (25 mm m-2, correspondant à une biomasse de 250 g m-2. Le modèle explicatif de la densité généré par analyse de régression multiple pas-à-pas explique 60,0 % de la variabilité de la densité par les variables vitesse de courant, température de l'eau et date d'échantillonnage, cette variable intégrant le concept de mortalité-dispersion au cours de la saison de croissance. Les implications de la méthodologie et des résultats présentés au plan de la gestion des écosystèmes lotiques sont brièvement discutés.

Improvement of spectrographic analyses by the use of a mechanical packer in the arc distillation technique; Amelioration de l'analyse spectrograpique par l'utilisation d'un tasseur mecanique dans la methode de distillation dans l'arc

Energy Technology Data Exchange (ETDEWEB)

Buffereau, M; Deniaud, S; Pichotin, B; Violet, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-07-01

One studies improvement of spectrographic analysis by the 'carrier distillation' method with the help of a mechanical device. Experiments and advantages of such an apparatus are given (precision and reproducibility improvement, operator factor suppression). A routine apparatus (French patent no 976.493) is described. (authors) [French] On etudie l'amelioration des analyses spectrographiques par la methode de distillation avec entra eur dans l'arc au moyen d'un tasseur mecanique. On indique les experiences realisees et les avantages de l'emploi d'un tel appareil (amelioration de la precision et de la reproductibilite, suppression du facteur operateur). On decrit l'appareil de routine objet du brevet no 976.493 du 29 mai 1964. (auteurs)

Par Pond vegetation status 1996

International Nuclear Information System (INIS)

Mackey, H.E. Jr.; Riley, R.S.

1996-12-01

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995, and into the early spring and late summer of 1996. Communities similar to the pre-drawdown, Par Pond aquatic plant communities continue to become re-established. Emergent beds of maidencane, lotus, waterlily, watershield, and Pontederia are extensive and well developed. Measures of percent cover, width of beds, and estimates of area of coverage with satellite data indicate regrowth within two years of from 40 to 60% of levels prior to the draw down. Cattail occurrence continued to increase during the summer of 1996, especially in the former warm arm of Par Pond, but large beds common to Par Pond prior to the draw down still have not formed. Lotus has invaded and occupies many of the areas formerly dominated by cattail beds. To track the continued development of macrophytes in Par Pond, future surveys through the summer and early fall of 1997, along with the evaluation of satellite data to map the extent of the macrophyte beds of Par Pond, are planned

Analysis of solids by spark-source mass spectrometry; Analyse des solides au spectrometre de masse a etincelles

Energy Technology Data Exchange (ETDEWEB)

Stefani, R; Desjardins, M; Brun, J C; Cornu, A; Bourguillot, R [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1965-07-01

Spark source mass spectrometer MS7 has been designed to determine traces of impurities in solids without standards. An atlas of 12 000 lines, assembled in the Grenoble laboratory, allows a quick investigation of mass spectra, notwithstanding their complexity due to multiply charged and polyatomic darkening. Photometric measurements increase accuracy calibration curve is known for each photo-plate. Further, reproducibility is better, if random fluctuations of matrix line darkening are corrected. So far, in a concentration range of 0,01 to 1 000 ppm (atomic), reproducibility is approximately 20 per cent, but absolute value of results depends on 'sensitivity coefficients'. (authors) [French] Le spectrometre de masse a etincelles, de type MS7, est destine a l'analyse chimique de traces dans les solides, sans echantillons etalons. L'emploi de catalogues de 12 000 raies, elabores au laboratoire, permet un depouillement rapide des spectres, malgre leur complexite due aux ionisations multiples et aux associations d'atomes. Le niveau d'apparition d'une impurete donne une estimation de sa teneur, mais la valeur du renseignement depend de la preparation des electrodes et de la connaissance plus ou moins approfondie des processus d'ionisation dans l'etincelle et de noircissement des emulsions photographiques. Les mesures photometriques augmentent la precision des resultats, si l'on determine systematiquement la courbe de noircissement de chaque plaque. De meme la reproductibilite est amelioree si l'on tient compte des fluctuations statistiques du noircissement de l'emulsion par les ions de la matrice. Actuellement, les concentrations mesurees dans le domaine de 0,01 a 1000 ppm atomiques sont reproductibles a 20 pour cent pres, mais leur valeur absolue n'est assuree qu'a un coefficient 3 pres. Des etudes sont en cours pour calibrer l'appareil en valeur absolue, par une determination des coefficients de sensibilite a partir d'echantillons etalons. (auteurs)

Forensic Mass Spectrometry

Science.gov (United States)

Hoffmann, William D.; Jackson, Glen P.

2015-07-01

Developments in forensic mass spectrometry tend to follow, rather than lead, the developments in other disciplines. Examples of techniques having forensic potential born independently of forensic applications include ambient ionization, imaging mass spectrometry, isotope ratio mass spectrometry, portable mass spectrometers, and hyphenated chromatography-mass spectrometry instruments, to name a few. Forensic science has the potential to benefit enormously from developments that are funded by other means, if only the infrastructure and personnel existed to adopt, validate, and implement the new technologies into casework. Perhaps one unique area in which forensic science is at the cutting edge is in the area of chemometrics and the determination of likelihood ratios for the evaluation of the weight of evidence. Such statistical techniques have been developed most extensively for ignitable-liquid residue analyses and isotope ratio analysis. This review attempts to capture the trends, motivating forces, and likely impact of developing areas of forensic mass spectrometry, with the caveat that none of this research is likely to have any real impact in the forensic community unless: (a) The instruments developed are turned into robust black boxes with red and green lights for positives and negatives, respectively, or (b) there are PhD graduates in the workforce who can help adopt these sophisticated techniques.

Cyclodextrin--piroxicam inclusion complexes: analyses by mass spectrometry and molecular modelling

Science.gov (United States)

Gallagher, Richard T.; Ball, Christopher P.; Gatehouse, Deborah R.; Gates, Paul J.; Lobell, Mario; Derrick, Peter J.

1997-11-01

Mass spectrometry has been used to investigate the natures of non-covalent complexes formed between the anti-inflammatory drug piroxicam and [alpha]-, [beta]- and [gamma]-cyclodextrins. Energies of these complexes have been calculated by means of molecular modelling. There is a correlation between peak intensities in the mass spectra and the calculated energies.

uPAR Expression Pattern in Patients with Urothelial Carcinoma of the Bladder--Possible Clinical Implications.

Directory of Open Access Journals (Sweden)

Line Hammer Dohn

Full Text Available The objective of the present study was to confirm the expression and localisation pattern of the urokinase-type plasminogen activator receptor (uPAR focusing on its possible clinical relevance in patients with urothelial neoplasia of the bladder. uPAR is a central molecule in tissue remodelling during cancer invasion and metastasis and is an established prognostic marker in various cancer diseases other than bladder cancer. Formalin-fixed and paraffin-embedded tumour-tissue blocks from 186 patients treated with radical cystectomy were analysed. uPAR expression was scored as either negative or positive as well as by the actual score. Separate scores were obtained for cancer cells, macrophages and myofibroblasts at the invasive front and in tumour core. We were able to confirm, in an independent patient cohort, the tissue expression and localisation pattern of uPAR as investigated by Immunohistochemistry as well as a significant association between uPAR positivity and increasing tumour stage and tumour grade. This demonstrates the robustness of our previous and current findings. In addition the association between uPAR positive myofibroblasts and poor survival was reproduced. The highest hazard ratios for survival were seen for uPAR positive myofibroblasts both at the invasive front and in tumour core. Evaluating uPAR expression by the actual score showed a significant association between uPAR positive myofibroblasts in tumour core and an increased risk of cancer specific mortality. Our investigations have generated new and valuable biological information about the cell types being involved in tumour invasion and progression through the plasminogen activation system.

Stable carbon isotope analyses of nanogram quantities of particulate organic carbon (pollen) with laser ablation nano combustion gas chromatography/isotope ratio mass spectrometry

Science.gov (United States)

Sluijs, Appy; Laks, Jelmer J.; Reichart, Gert‐Jan

2016-01-01

Rationale Analyses of stable carbon isotope ratios (δ 13C values) of organic and inorganic matter remains have been instrumental for much of our understanding of present and past environmental and biological processes. Until recently, the analytical window of such analyses has been limited to samples containing at least several μg of carbon. Methods Here we present a setup combining laser ablation, nano combustion gas chromatography and isotope ratio mass spectrometry (LA/nC/GC/IRMS). A deep UV (193 nm) laser is used for optimal fragmentation of organic matter with minimum fractionation effects and an exceptionally small ablation chamber and combustion oven are used to reduce the minimum sample mass requirement compared with previous studies. Results Analyses of the international IAEA CH‐7 polyethylene standard show optimal accuracy, and precision better than 0.5‰, when measuring at least 42 ng C. Application to untreated modern Eucalyptus globulus (C3 plant) and Zea mays (C4 plant) pollen grains shows a ~ 16‰ offset between these species. Within each single Z. mays pollen grain, replicate analyses show almost identical δ 13C values. Conclusions Isotopic offsets between individual pollen grains exceed analytical uncertainties, therefore probably reflecting interspecimen variability of ~0.5–0.9‰. These promising results set the stage for investigating both δ 13C values and natural carbon isotopic variability between single specimens of a single population of all kinds of organic particles yielding tens of nanograms of carbon. © 2016 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd. PMID:27766694

Densité, morphologie urbaine et qualité de vie. Une approche par le projet

OpenAIRE

Occhiuto, Rita; Goossens, Marc; Fisher, Axel

2013-01-01

La recherche "Densification des tissus urbanisés en Wallonie: forme, acceptabilité et modalités pour accompagner la mutation des tissus bâtis" s'articule en plusieurs volets thématiques, parmi lesquels figure le volet "formes urbaines, modes d'habitat". Ce dernier volet est abordé selon deux approches parallèles et complémentaires qui se valident mutuellement: la première dite "par le projet" (approche qualitative et opérationnelle) et la seconde par analyse statistique et cartographique (ap...

Direct Analyses of Secondary Metabolites by Mass Spectrometry Imaging (MSI) from Sunflower (Helianthus annuus L.) Trichomes.

Science.gov (United States)

Brentan Silva, Denise; Aschenbrenner, Anna-Katharina; Lopes, Norberto Peporine; Spring, Otmar

2017-05-10

Helianthus annuus (sunflower) displays non-glandular trichomes (NGT), capitate glandular trichomes (CGT), and linear glandular trichomes (LGT), which reveal different chemical compositions and locations in different plant tissues. With matrix-assisted laser desorption/ionization (MALDI) and laser desorption/ionization (LDI) mass spectrometry imaging (MSI) techniques, efficient methods were developed to analyze the tissue distribution of secondary metabolites (flavonoids and sesquiterpenes) and proteins inside of trichomes. Herein, we analyzed sesquiterpene lactones, present in CGT, from leaf transversal sections using the matrix 2,5-dihydroxybenzoic acid (DHB) and α-cyano-4-hydroxycinnamic acid (CHCA) (mixture 1:1) with sodium ions added to increase the ionization in positive ion mode. The results observed for sesquiterpenes and polymethoxylated flavones from LGT were similar. However, upon desiccation, LGT changed their shape in the ionization source, complicating analyses by MSI mainly after matrix application. An alternative method could be applied to LGT regions by employing LDI (without matrix) in negative ion mode. The polymethoxylated flavones were easily ionized by LDI, producing images with higher resolution, but the sesquiterpenes were not observed in spectra. Thus, the application and viability of MALDI imaging for the analyses of protein and secondary metabolites inside trichomes were confirmed, highlighting the importance of optimization parameters.

Quantitation of Poly(ADP-Ribose) by Isotope Dilution Mass Spectrometry

DEFF Research Database (Denmark)

Zubel, Tabea; Martello, Rita; Bürkle, Alexander

2017-01-01

PARP inhibitors, which represent a novel class of promising chemotherapeutics. Previously, we have developed a bioanalytical platform based on isotope dilution mass spectrometry (LC-MS/MS) to quantify cellular PAR with unequivocal chemical specificity in absolute terms with femtomol sensitivity...... research, as well as in drug development (Martello et al. ACS Chem Biol 8(7):1567-1575, 2013; Mangerich et al. Toxicol Lett 244:56-71, 2016). Here, we present an improved and adjusted version of the original protocol by Martello/Mangerich et al., which uses UPLC-MS/MS instrumentation....

Contribution to the studies on the mineral content of plant material through radioactivation analysis; Contribution a l'etude de la composition minerale des matieres vegetales au moyen de l'analyse par radioactivation

Energy Technology Data Exchange (ETDEWEB)

Fourcy, A [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1968-03-15

Radioactivation analysis is by its great sensibility or its rapidity quite helpful in plant biology and agronomy. Specific composition of plants and results to obtain in biological experimentation have needed a practical research on analytical methods for plant materials, using for radioactivation swimming-pool reactor neutrons and 14 MeV neutrons from a generator. Dosage process for 25 elements is exposed, taking account of the interest of the analysis for each element, the average amount occurring in plants and the result obtained. Many applications are developed, concerning nutrition physiology, genetics, parasitology, toxicology, control of manufactured agricultural and pharmaceutical products industrial and pesticides residues, ecology, radioecology and biochemistry. (author) [French] L'analyse par radioactivation, par sa grande sensibilite ou sa rapidite, est susceptible de rendre de nombreux services en biologie vegetale et en agronomie. La composition particuliere des plantes et les buts recherches dans l'experimentation ont exige une etude concrete des methodes d'analyse propres a la matiere vegetale en utilisant, pour la radioactivation, soit un reacteur de type piscine a eau legere, soit un accelerateur generateur de neutrons de 14 MeV. Le mode de dosage de 25 elements est expose en tenant compte de l'interet de l'analyse de chaque element, des teneurs moyennes rencontrees dans les plantes, et du resultat atteint. De nombreuses applications sont developpees qui touchent a la physiologie de la nutrition, la genetique, la parasitologie, la toxicologie, le controle des fabrications, les pollutions industrielles, l'ecologie, la radioecologie et la biochimie. (auteur)

Analyse des stratégies d’apprentissage dans une méthode d’apprentissage par problèmes : le cas d’étudiantes en soins infirmiers

Directory of Open Access Journals (Sweden)

Caroline Larue

2009-09-01

Full Text Available Plusieurs institutions d’enseignement supérieur ont adopté l’apprentissage par problèmes comme méthode pédagogique, mais peu d’études, à notre connaissance, se sont intéressées à décrire les stratégies utilisées par les étudiants dans un curriculum d’apprentissage par problèmes. Le but de cette recherche est justement l’étude de ces stratégies. L’analyse des verbatims obtenus auprès de 31 étudiantes1 de soins infirmiers a permis de dégager un ensemble de stratégies et d’en évaluer la fréquence. Les résultats suggèrent que les étudiantes utilisent davantage des stratégies de traitement en surface de l’information que des stratégies de traitement en profondeur malgré des indications voulant que l’utilisation d’une approche en profondeur soit associée à une meilleure réussite au cours.Several higher education institutions have adopted problem-based learning as an educational method. But, as far as we know, very few studies try to describe the strategies which are used by students in order to succeed in a problem-based learning context. The purpose of this research is to study those strategies. The analysis of the verbatim obtained from 31 nursing students uncovered the main strategies and their respective frequency. The results suggest that the students are more likely to use strategies based on surface treatment of the information than in-depth learning strategies. This preference is maintained even though they were told that in-depth learning strategies increase their academic achievements.

Protease-activated receptor (PAR)-2 is required for PAR-1 signalling in pulmonary fibrosis

NARCIS (Netherlands)

Lin, Cong; von der Thüsen, Jan; Daalhuisen, Joost; ten Brink, Marieke; Crestani, Bruno; van der Poll, Tom; Borensztajn, Keren; Spek, C. Arnold

2015-01-01

Idiopathic pulmonary fibrosis is the most devastating diffuse fibrosing lung disease of unknown aetiology. Compelling evidence suggests that both protease-activated receptor (PAR)-1 and PAR-2 participate in the development of pulmonary fibrosis. Previous studies have shown that bleomycin-induced

Mass spectrometry a versatile aid to inorganic analysis

International Nuclear Information System (INIS)

Stefani, Rene

1976-01-01

Several hundred publications have appeared in the last three years that deal with applications of Mass Spectrometry to inorganic analysis. Bulk and localized trace analysis, surface and thin film characterization and microstructure examination are currently performed by Secondary Ion Mass Spectrometry, Spark Source Mass Spectrometry and the newly developed Laser Probe Mass Spectrometry. Suitable experimental procedures allow insulators, biologic materials and microsamples to be analysed. In spite of the classification by techniques this review is essentially devoted to the most significant papers in analytical applications but instrumental and basic features are sometimes introduced to support the discussions

Evaluation of Passive Autocatalytic Recombiner (PAR) Implementation in a Konvoi NPP Containment Type

Energy Technology Data Exchange (ETDEWEB)

Lopez-Alonso, E.; Papini, D.; Jimenez, G.

2015-07-01

The evaluation of Passive Autocatalytic Recombiner (PAR) implementation has been developed under the methodology extracted from the IAEA document, analysing the size, location and number of the PARs capable to minimize the combustion risk, which arises from a hydrogen release generated during a severe accident and its distribution in containment building. A detailed three-dimensional model of Konvoi (PWR) containment with GOTHIC 8.1 code was used for the simulations. The hydrogen preferential pathways and the accumulation points were studied and identified on the basis of a base case scenario without any mitigation measure. The PAR configuration offers an improvement in the chosen accidental scenario; decreasing the possibility of hydrogen combustion and leading to concentration values below the flammability limit (hydrogen concentration below 7%), in all the containment compartments at the end of the transient. Furthermore, from the analysis, it is concluded that the time required to reach hydrogen concentrations below the combustion limit is considerably reduced. (Author)

Laser desorption and time-of-flight mass spectrometry. Fundamentals .Applications; Desorption laser et spectrometrie de masse par temps de vol. Aspects fondamentaux. Applications

Energy Technology Data Exchange (ETDEWEB)

Chaurand, P

1994-11-01

Time-of-flight mass spectrometry is a very powerful technique for the analysis of heavy molecular ions (100 000 u and more). The ejection in the gas phase and the ionization of these molecules is now possible through the MALDI technique (Matrix Assisted Laser Desorption Ionization). This technique consists in mixing the heavy molecules to be analysed with a organic matrix which absorbs at the wavelength of the laser. The necessary irradiance are of the order of 10{sup 6} W/cm{sup 2}. In these conditions we have shown that the mass resolutions are optimum and that the relative mass accuracies are of the order of 10{sup -4}. We have also demonstrated that the emission angle of the molecular ions in MALDI depends on the incident angle of the laser light. During the desorption process, the molecular ions are emitted in the opposite direction of the incident laser light. This effect is particularly important for the design of the accelerating stage of the time-of-flight spectrometers. Problems relative to the detection of these heavy molecular ions have been studied in details between 0.5 10{sup 4} m/s and 10{sup 5} m/s. The velocity threshold of the electronic emission is lower than the value of 0.5 10{sup 4} m/s. The relation between the electronic emission and the projectile velocity is complex. Finally, examples on mass identification of C{sub 60} molecules and derivated C{sub 60} are presented. Desorption methods are compared. (author). 32 refs., 34 figs.

Par Pond vegetation status Summer 1995 -- Summary

International Nuclear Information System (INIS)

Mackey, H.E. Jr.; Riley, R.S.

1996-01-01

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the newly emergent, shoreline aquatic plant communities of Par Pond began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level. These surveys continued in July, September, and late October, 1995. Communities similar to the pre-drawdown, Par Pond aquatic plant communities are becoming re-established. Emergent beds of maidencane, lotus, waterlily, and watershield are extensive and well developed. Cattail occurrence continued to increase during the summer, but large beds common to Par Pond prior to the drawdown have not formed. Estimates from SPOT HRV, remote sensing satellite data indicated that as much as 120 hectares of emergent wetlands vegetation may have been present along the Par Pond shoreline by early October, 1995. To track the continued development of macrophytes in Par Pond, future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned

Contribution to the studies on the mineral content of plant material through radioactivation analysis; Contribution a l'etude de la composition minerale des matieres vegetales au moyen de l'analyse par radioactivation

Energy Technology Data Exchange (ETDEWEB)

Fourcy, A. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1968-03-15

Radioactivation analysis is by its great sensibility or its rapidity quite helpful in plant biology and agronomy. Specific composition of plants and results to obtain in biological experimentation have needed a practical research on analytical methods for plant materials, using for radioactivation swimming-pool reactor neutrons and 14 MeV neutrons from a generator. Dosage process for 25 elements is exposed, taking account of the interest of the analysis for each element, the average amount occurring in plants and the result obtained. Many applications are developed, concerning nutrition physiology, genetics, parasitology, toxicology, control of manufactured agricultural and pharmaceutical products industrial and pesticides residues, ecology, radioecology and biochemistry. (author) [French] L'analyse par radioactivation, par sa grande sensibilite ou sa rapidite, est susceptible de rendre de nombreux services en biologie vegetale et en agronomie. La composition particuliere des plantes et les buts recherches dans l'experimentation ont exige une etude concrete des methodes d'analyse propres a la matiere vegetale en utilisant, pour la radioactivation, soit un reacteur de type piscine a eau legere, soit un accelerateur generateur de neutrons de 14 MeV. Le mode de dosage de 25 elements est expose en tenant compte de l'interet de l'analyse de chaque element, des teneurs moyennes rencontrees dans les plantes, et du resultat atteint. De nombreuses applications sont developpees qui touchent a la physiologie de la nutrition, la genetique, la parasitologie, la toxicologie, le controle des fabrications, les pollutions industrielles, l'ecologie, la radioecologie et la biochimie. (auteur)

Risques naturels en montagne et analyse spatiale

Directory of Open Access Journals (Sweden)

Yannick Manche

1999-06-01

Full Text Available Le concept de risque repose sur deux notions :l'aléa, qui représente le phénomène physique par son amplitude et sa période retour ;la vulnérabilité, qui représente l'ensemble des biens et des personnes pouvant être touchés par un phénomène naturel.Le risque se définit alors comme le croisement de ces deux notions. Cette vision théorique permet de modéliser indépendamment les aléas et la vulnérabilité.Ce travail s'intéresse essentiellement à la prise en compte de la vulnérabilité dans la gestion des risques naturels. Son évaluation passe obligatoirement par une certaine analyse spatiale qui prend en compte l'occupation humaine et différentes échelles de l'utilisation de l'espace. Mais l'évaluation spatiale, que ce soit des biens et des personnes, ou des effets indirects se heurte à de nombreux problèmes. Il faut estimer l'importance de l'occupation de l'espace. Par ailleurs, le traitement des données implique des changements constants d'échelle pour passer des éléments ponctuels aux surfaces, ce que les systèmes d'information géographique ne gèrent pas parfaitement. La gestion des risques entraîne de fortes contraintes d'urbanisme, la prise en compte de la vulnérabilité permet de mieux comprendre et gérer les contraintes spatiales qu'impliquent les risques naturels. aléa, analyse spatiale, risques naturels, S.I.G., vulnérabilité

The use of secondary ion mass spectrometry in forensic analyses of ultra-small samples

Science.gov (United States)

Cliff, John

2010-05-01

It is becoming increasingly important in forensic science to perform chemical and isotopic analyses on very small sample sizes. Moreover, in some instances the signature of interest may be incorporated in a vast background making analyses impossible by bulk methods. Recent advances in instrumentation make secondary ion mass spectrometry (SIMS) a powerful tool to apply to these problems. As an introduction, we present three types of forensic analyses in which SIMS may be useful. The causal organism of anthrax (Bacillus anthracis) chelates Ca and other metals during spore formation. Thus, the spores contain a trace element signature related to the growth medium that produced the organisms. Although other techniques have been shown to be useful in analyzing these signatures, the sample size requirements are generally relatively large. We have shown that time of flight SIMS (TOF-SIMS) combined with multivariate analysis, can clearly separate Bacillus sp. cultures prepared in different growth media using analytical spot sizes containing approximately one nanogram of spores. An important emerging field in forensic analysis is that of provenance of fecal pollution. The strategy of choice for these analyses-developing host-specific nucleic acid probes-has met with considerable difficulty due to lack of specificity of the probes. One potentially fruitful strategy is to combine in situ nucleic acid probing with high precision isotopic analyses. Bulk analyses of human and bovine fecal bacteria, for example, indicate a relative difference in d13C content of about 4 per mil. We have shown that sample sizes of several nanograms can be analyzed with the IMS 1280 with precisions capable of separating two per mil differences in d13C. The NanoSIMS 50 is capable of much better spatial resolution than the IMS 1280, albeit at a cost of analytical precision. Nevertheless we have documented precision capable of separating five per mil differences in d13C using analytical spots containing

ParABS system in chromosome partitioning in the bacterium Myxococcus xanthus.

Directory of Open Access Journals (Sweden)

Antonio A Iniesta

Full Text Available Chromosome segregation is an essential cellular function in eukaryotic and prokaryotic cells. The ParABS system is a fundamental player for a mitosis-like process in chromosome partitioning in many bacterial species. This work shows that the social bacterium Myxococcus xanthus also uses the ParABS system for chromosome segregation. Its large prokaryotic genome of 9.1 Mb contains 22 parS sequences near the origin of replication, and it is shown here that M. xanthus ParB binds preferentially to a consensus parS sequence in vitro. ParB and ParA are essential for cell viability in M. xanthus as in Caulobacter crescentus, but unlike in many other bacteria. Absence of ParB results in anucleate cells, chromosome segregation defects and loss of viability. Analysis of ParA subcellular localization shows that it clusters at the poles in all cells, and in some, in the DNA-free cell division plane between two chromosomal DNA masses. This ParA localization pattern depends on ParB but not on FtsZ. ParB inhibits the nonspecific interaction of ParA with DNA, and ParA colocalizes with chromosomal DNA only when ParB is depleted. The subcellular localization of ParB suggests a single ParB-parS complex localized at the edge of the nucleoid, next to a polar ParA cluster, with a second ParB-parS complex migrating after the replication of parS takes place to the opposite nucleoid edge, next to the other polar ParA cluster.

Processing of data issued from a {gamma} spectrometer; Traitement des informations issues d'un spectrometre {gamma}

Energy Technology Data Exchange (ETDEWEB)

Boulanger, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1966-03-01

The purpose of the following report is the study of computation method applied to analysis by gamma spectrometry. We first study quantitative analysis by the least-squares method, improved by a gain-shift correction. Then the single full-energy peaks and the resolution of complex peaks are dealt with. In both cases, the calculation principle, then the systematic tests achieved in order to-prove their validity and determine their application ranges are described and finally some experimental results appropriate to illustrate their possibilities are presented. (author) [French] Le present rapport a pour objet l'etude de methodes de calcul applicables a l'analyse par spectrometrie gamma. On etudie d'abord l'analyse quantitative par la methode des moindres carres, completee par une correction de derive du gain. Puis on examine les pics d'absorption totale simples et la resolution des pics complexes. Dans les deux cas, on expose le principe des calculs et les essais systematiques effectues pour eprouver leur validite et definir leurs domaines d'application, ainsi que quelques resultats experimentaux propres a illustrer leurs possibilites.

Etude par imagerie radar des pollutions pétrolières

Directory of Open Access Journals (Sweden)

G. Rees

2004-06-01

Full Text Available En Russie, chaque année, les déversements de pétrole représentent un cinquième de la production totale. Les plus importants se produisent dans le domaine périglaciaire où le milieu naturel est d’une extrême fragilité. Les pipelines sont soumis à de rudes conditions notamment à la corrosion et aux processus cryogéniques. Le risque de rupture augmente en conséquence. La surveillance des déversements d’hydrocarbures, contrainte par l’immensité et la fréquente inaccessibilité du réseau de pipelines, peut être réalisée par le recours à la télédétection. L’objectif de ce travail est de fournir, à travers l’exemple de la catastrophe d’Usinsk (Rép. de Komi survenue en 1994, des outils d’analyse des images radar. Outre leur capacité à s’affranchir du couvert nuageux, les capteurs radar apportent des informations complémentaires à celles fournies par des capteurs optiques. L’exploitation thématique de ces images est rendue difficile par un certain nombre de facteurs perturbateurs tels que les caractéristiques propres du capteur, la direction de visée, la topographie et le phénomène de chatoiement (speckle. Le travail présenté montre le rôle prépondérant joué par ces corrections qui permettent de disposer de données quantitatives comparables d’une date à une autre. La méthode mise au point ici pour le suivi temporel de l’épanchement de pétrole d’Usinsk à partir de trois images radar, est discutée notamment dans ses limites et son aspect opérationnel possible.

Computational analyses of spectral trees from electrospray multi-stage mass spectrometry to aid metabolite identification.

Science.gov (United States)

Cao, Mingshu; Fraser, Karl; Rasmussen, Susanne

2013-10-31

Mass spectrometry coupled with chromatography has become the major technical platform in metabolomics. Aided by peak detection algorithms, the detected signals are characterized by mass-over-charge ratio (m/z) and retention time. Chemical identities often remain elusive for the majority of the signals. Multi-stage mass spectrometry based on electrospray ionization (ESI) allows collision-induced dissociation (CID) fragmentation of selected precursor ions. These fragment ions can assist in structural inference for metabolites of low molecular weight. Computational investigations of fragmentation spectra have increasingly received attention in metabolomics and various public databases house such data. We have developed an R package "iontree" that can capture, store and analyze MS2 and MS3 mass spectral data from high throughput metabolomics experiments. The package includes functions for ion tree construction, an algorithm (distMS2) for MS2 spectral comparison, and tools for building platform-independent ion tree (MS2/MS3) libraries. We have demonstrated the utilization of the package for the systematic analysis and annotation of fragmentation spectra collected in various metabolomics platforms, including direct infusion mass spectrometry, and liquid chromatography coupled with either low resolution or high resolution mass spectrometry. Assisted by the developed computational tools, we have demonstrated that spectral trees can provide informative evidence complementary to retention time and accurate mass to aid with annotating unknown peaks. These experimental spectral trees once subjected to a quality control process, can be used for querying public MS2 databases or de novo interpretation. The putatively annotated spectral trees can be readily incorporated into reference libraries for routine identification of metabolites.

Analysis of ParB-centromere interactions by multiplex SPR imaging reveals specific patterns for binding ParB in six centromeres of Burkholderiales chromosomes and plasmids.

Science.gov (United States)

Pillet, Flavien; Passot, Fanny Marie; Pasta, Franck; Anton Leberre, Véronique; Bouet, Jean-Yves

2017-01-01

Bacterial centromeres-also called parS, are cis-acting DNA sequences which, together with the proteins ParA and ParB, are involved in the segregation of chromosomes and plasmids. The specific binding of ParB to parS nucleates the assembly of a large ParB/DNA complex from which ParA-the motor protein, segregates the sister replicons. Closely related families of partition systems, called Bsr, were identified on the chromosomes and large plasmids of the multi-chromosomal bacterium Burkholderia cenocepacia and other species from the order Burkholeriales. The centromeres of the Bsr partition families are 16 bp palindromes, displaying similar base compositions, notably a central CG dinucleotide. Despite centromeres bind the cognate ParB with a narrow specificity, weak ParB-parS non cognate interactions were nevertheless detected between few Bsr partition systems of replicons not belonging to the same genome. These observations suggested that Bsr partition systems could have a common ancestry but that evolution mostly erased the possibilities of cross-reactions between them, in particular to prevent replicon incompatibility. To detect novel similarities between Bsr partition systems, we have analyzed the binding of six Bsr parS sequences and a wide collection of modified derivatives, to their cognate ParB. The study was carried out by Surface Plasmon Resonance imaging (SPRi) mulitplex analysis enabling a systematic survey of each nucleotide position within the centromere. We found that in each parS some positions could be changed while maintaining binding to ParB. Each centromere displays its own pattern of changes, but some positions are shared more or less widely. In addition from these changes we could speculate evolutionary links between these centromeres.

La pelade par plaques

Science.gov (United States)

Spano, Frank; Donovan, Jeff C.

2015-01-01

Résumé Objectif Présenter aux médecins de famille des renseignements de base pour faire comprendre l’épidémiologie, la pathogenèse, l’histologie et l’approche clinique au diagnostic de la pelade par plaques. Sources des données Une recension a été effectuée dans PubMed pour trouver des articles pertinents concernant la pathogenèse, le diagnostic et le pronostic de la pelade par plaques. Message principal La pelade par plaques est une forme de perte pileuse auto-immune dont la prévalence durant une vie est d’environ 2 %. Des antécédents personnels ou familiaux de troubles auto-immuns concomitants, comme le vitiligo ou une maladie de la thyroïde, peuvent être observés dans un petit sous-groupe de patients. Le diagnostic peut souvent être posé de manière clinique en se fondant sur la perte de cheveux non cicatricielle et circulaire caractéristique, accompagnée de cheveux en « point d’exclamation » en périphérie chez ceux dont le problème en est aux premiers stades. Le diagnostic des cas plus complexes ou des présentations inhabituelles peut être facilité par une biopsie et un examen histologique. Le pronostic varie largement et de mauvais résultats sont associés à une apparition à un âge précoce, une perte importante, la variante ophiasis, des changements aux ongles, des antécédents familiaux ou des troubles auto-immuns concomitants. Conclusion La pelade par plaques est une forme auto-immune de perte de cheveux périodiquement observée en soins primaires. Les médecins de famille sont bien placés pour identifier la pelade par plaques, déterminer la gravité de la maladie et poser le diagnostic différentiel approprié. De plus, ils sont en mesure de renseigner leurs patients à propos de l’évolution clinique de la maladie ainsi que du pronostic général selon le sous-type de patients.

L'analyse des corpus multimodaux en ligne : état des lieux et perspectives

Directory of Open Access Journals (Sweden)

Develotte Christine

2012-07-01

Full Text Available Partant de l’ouvrage "Texte et ordinateur. L’écriture réinventée ?" de Jacques Anis (1998 nous cherchons à montrer la trajectoire des travaux français en sciences du langage sur les corpus médiés par la technologie jusqu’à aujourd’hui. La communication en ligne renvoie à des formes diverses selon qu’il s’agit de la production de textes fixes (par exemple, sites Web, courriels ou de formes plutôt centrées sur les processus d’interaction et de communication (par exemple, chat, visioconférence susceptibles donc d’être étudiées tant du point de vue de l’analyse du discours que de celui de l’analyse conversationnelle. Nous nous proposons de montrer, dans cet article, dans quelle mesure les deux traditions en sciences du langage ont trouvé matière à exploiter ces corpus en ligne en empiétant, parfois, l’une comme l’autre, sur leurs « territoires » respectifs. Dans cette perspective, nous commençons par mettre au jour l’apport des chercheurs revendiquant leur appartenance à l’analyse du discours, puis celui des chercheurs relevant de l’analyse des interactions et nous montrons les zones de tuilage entre les deux courants. Dans une dernière partie, nous nous intéressons aux défis juridiques, techniques et épistémologiques que doit relever le linguiste qui cherche à étudier des corpus multimodaux en ligne qui prennent des formes de plus en plus sophistiquées et complexes.

Keratometric alterations following the 25-gauge transconjunctival sutureless pars plana vitrectomy versus the conventional pars plana vitrectomy.

Science.gov (United States)

Citirik, Mehmet; Batman, Cosar; Bicer, Tolga; Zilelioglu, Orhan

2009-09-01

To assess the alterations in keratometric astigmatism following the 25-gauge transconjunctival sutureless pars plana vitrectomy versus the conventional pars plana vitrectomy. Sixteen consecutive patients were enrolled into the study. Conventional vitrectomy was applied to eight of the cases and 25-gauge transconjunctival sutureless vitrectomy was performed in eight patients. Keratometry was performed before and after the surgery. In the 25-gauge transconjunctival sutureless pars plana vitrectomy group, statistically significant changes were not observed in the corneal curvature in any post-operative follow-up measurement (p > 0.05); whereas in the conventional pars plana vitrectomy group, statistically significant changes were observed in the first postoperative day (p = 0.01) and first postoperative month (p = 0.03). We noted that these changes returned to baseline in three months (p = 0.26). Both 25-gauge transconjunctival sutureless and conventional pars plana vitrectomy are effective surgical modalities for selected diseases of the posterior segment. Surgical procedures are critical for the visual rehabilitation of the patients. The post-operative corneal astigmatism of the vitrectomised eyes can be accurately determined at least two months post-operatively.

Measurement and analysis of high energy radiation through activation detectors. Application in dosimetry; Sur la mesure et l'analyse des rayonnements de haute energie par detecteurs a activation. Application a la dosimetrie

Energy Technology Data Exchange (ETDEWEB)

Sklavenitis, L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-10-15

reactions nucleaires a tres haute energie est realisee ainsi que la mesure et le calcul des sections efficaces d'un certain nombre de reactions, comme la reaction {sup 11}B (p,n) {sup 11}C entre 150 et 3000 MeV et la reaction {sup 34}S (p,2pn) {sup 32}P entre 50 et 3000 MeV. La deuxieme partie est relative a l'application de l'analyse des fluences dans un fantome equivalent aux tissus irradie par des protons de 3 GeV. Cette analyse est suffisamment detaillee pour permettre de reconstituer les doses absorbees, les equivalents de dose et, sous reserve d'une meilleure connaissance de la dose due aux particules lourdes, les facteurs de qualite. Elle a permis, par ailleurs, de suivre l'evolution des differentes donnees dosimetriques en fonction de la profondeur dans le fantome et d'effectuer une verification des calculs deja faits par d'autres chercheurs. La comparaison des doses mesurees et des activites correspondantes de certains detecteurs a revele une qualite de ces derniers pouvant eventuellement conduire a la mise au point d'un detecteur qui donnerait directement la dose absorbee ou meme l'equivalent de dose par simple mesure de son activite. (auteur)

Centromere pairing by a plasmid-encoded type I ParB protein

DEFF Research Database (Denmark)

Ringgaard, Simon; Löwe, Jan; Gerdes, Kenn

2007-01-01

The par2 locus of Escherichia coli plasmid pB171 encodes two trans-acting proteins, ParA and ParB, and two cis-acting sites, parC1 and parC2, to which ParB binds cooperatively. ParA is related to MinD and oscillates in helical structures and thereby positions ParB/parC-carrying plasmids regularly......, hence identifying the N terminus of ParB as a requirement for ParB-mediated centromere pairing. These observations suggest that centromere pairing is an important intermediate step in plasmid partitioning mediated by the common type I loci....

Analysis of ParB-centromere interactions by multiplex SPR imaging reveals specific patterns for binding ParB in six centromeres of Burkholderiales chromosomes and plasmids.

Directory of Open Access Journals (Sweden)

Flavien Pillet

Full Text Available Bacterial centromeres-also called parS, are cis-acting DNA sequences which, together with the proteins ParA and ParB, are involved in the segregation of chromosomes and plasmids. The specific binding of ParB to parS nucleates the assembly of a large ParB/DNA complex from which ParA-the motor protein, segregates the sister replicons. Closely related families of partition systems, called Bsr, were identified on the chromosomes and large plasmids of the multi-chromosomal bacterium Burkholderia cenocepacia and other species from the order Burkholeriales. The centromeres of the Bsr partition families are 16 bp palindromes, displaying similar base compositions, notably a central CG dinucleotide. Despite centromeres bind the cognate ParB with a narrow specificity, weak ParB-parS non cognate interactions were nevertheless detected between few Bsr partition systems of replicons not belonging to the same genome. These observations suggested that Bsr partition systems could have a common ancestry but that evolution mostly erased the possibilities of cross-reactions between them, in particular to prevent replicon incompatibility. To detect novel similarities between Bsr partition systems, we have analyzed the binding of six Bsr parS sequences and a wide collection of modified derivatives, to their cognate ParB. The study was carried out by Surface Plasmon Resonance imaging (SPRi mulitplex analysis enabling a systematic survey of each nucleotide position within the centromere. We found that in each parS some positions could be changed while maintaining binding to ParB. Each centromere displays its own pattern of changes, but some positions are shared more or less widely. In addition from these changes we could speculate evolutionary links between these centromeres.

Etk/Bmx regulates proteinase-activated-receptor1 (PAR1 in breast cancer invasion: signaling partners, hierarchy and physiological significance.

Directory of Open Access Journals (Sweden)

Irit Cohen

Full Text Available BACKGROUND: While protease-activated-receptor 1 (PAR(1 plays a central role in tumor progression, little is known about the cell signaling involved. METHODOLOGY/PRINCIPAL FINDINGS: We show here the impact of PAR(1 cellular activities using both an orthotopic mouse mammary xenograft and a colorectal-liver metastasis model in vivo, with biochemical analyses in vitro. Large and highly vascularized tumors were generated by cells over-expressing wt hPar1, Y397Z hPar1, with persistent signaling, or Y381A hPar1 mutant constructs. In contrast, cells over-expressing the truncated form of hPar1, which lacks the cytoplasmic tail, developed small or no tumors, similar to cells expressing empty vector or control untreated cells. Antibody array membranes revealed essential hPar1 partners including Etk/Bmx and Shc. PAR(1 activation induces Etk/Bmx and Shc binding to the receptor C-tail to form a complex. Y/A mutations in the PAR(1 C-tail did not prevent Shc-PAR(1 association, but enhanced the number of liver metastases compared with the already increased metastases obtained with wt hPar1. We found that Etk/Bmx first binds via the PH domain to a region of seven residues, located between C378-S384 in PAR(1 C-tail, enabling subsequent Shc association. Importantly, expression of the hPar1-7A mutant form (substituted A, residues 378-384, which is incapable of binding Etk/Bmx, resulted in inhibition of invasion through Matrigel-coated membranes. Similarly, knocking down Etk/Bmx inhibited PAR(1-induced MDA-MB-435 cell migration. In addition, intact spheroid morphogenesis of MCF10A cells is markedly disrupted by the ectopic expression of wt hPar1. In contrast, the forced expression of the hPar1-7A mutant results in normal ball-shaped spheroids. Thus, by preventing binding of Etk/Bmx to PAR(1 -C-tail, hPar1 oncogenic properties are abrogated. CONCLUSIONS/SIGNIFICANCE: This is the first demonstration that a cytoplasmic portion of the PAR(1 C-tail functions as a scaffold

CFD modelling of hydrogen stratification in enclosures: Model validation and application to PAR performance

Energy Technology Data Exchange (ETDEWEB)

Hoyes, J.R., E-mail: james.hoyes@hsl.gsi.gov.uk; Ivings, M.J.

2016-12-15

Highlights: • The ability of CFD to predict hydrogen stratification phenomena is investigated. • Contrary to expectation, simulations on tetrahedral meshes under-predict mixing. • Simulations on structured meshes give good agreement with experimental data. • CFD model used to investigate the effects of stratification on PAR performance. • Results show stratification can have a significant effect on PAR performance. - Abstract: Computational Fluid Dynamics (CFD) models are maturing into useful tools for supporting safety analyses. This paper investigates the capabilities of CFD models for predicting hydrogen stratification in a containment vessel using data from the NEA/OECD SETH2 MISTRA experiments. Further simulations are then carried out to illustrate the qualitative effects of hydrogen stratification on the performance of Passive Autocatalytic Recombiner (PAR) units. The MISTRA experiments have well-defined initial and boundary conditions which makes them well suited for use in a validation study. Results are presented for the sensitivity to mesh resolution and mesh type. Whilst the predictions are shown to be largely insensitive to the mesh resolution they are surprisingly sensitive to the mesh type. In particular, tetrahedral meshes are found to induce small unphysical convection currents that result in molecular diffusion and turbulent mixing being under-predicted. This behaviour is not unique to the CFD model used here (ANSYS CFX) and furthermore, it may affect simulations run on other non-aligned meshes (meshes that are not aligned perpendicular to gravity), including non-aligned structured meshes. Following existing best practice guidelines can help to identify potential unphysical predictions, but as an additional precaution consideration should be given to using gravity-aligned meshes for modelling stratified flows. CFD simulations of hydrogen recombination in the Becker Technologies THAI facility are presented with high and low PAR positions

Measurement of radioactive isotopes by {gamma} and x rays spectrometry with INa crystals. application to radiochemistry of some fission and activation products; Mesures d'isotopes radioactifs par spectrometrie {gamma} et x a l'aide de cristaux INa. application a la radiochimie de certains produits de fission et d'activation

Energy Technology Data Exchange (ETDEWEB)

Simonet, P; Boile, G; Simonet, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-07-01

The measurement of an number of atoms N may be obtained by detection of one {gamma} ray emitted if its branching ratio K{sub E} is known (number of E energy {gamma} transitions/number of disintegrations). N = A/{lambda} N{sub {gamma}}{sub E} / (K{sub E} * {lambda}) This measurement is effectuated in well-defined geometry, {gamma} rays emitted by the source are detected by a calibrated NaI crystal which is connected to a photomultiplier delivering electric impulses analysed by a multichannel analyser. Crystals are chosen according to energy, intensity of measured rays and of background. Calibration is established with standard sources or by total absolute efficiency of a definite crystal. Half-life, energy of measured photopeak branching ratio have been determined for these isotopes: Fission products: {sup 95}Zr, {sup 95}Nb, {sup 99}Mo, {sup 103}Ru, {sup 106}Ru, {sup 111}Ag, {sup 115}Cd, {sup 115m}Cd, {sup 132}Te, {sup 129m}Te, {sup 134}Cs, {sup 136}Cs, {sup 137}Cs, {sup 140}Ba, {sup 140}La. Rare earth elements: {sup 91}Y, {sup 141}Ce, {sup 144}Ce, {sup 147}Nd, {sup 156}Eu. Products from reactions (n, {gamma}) (n, 2n): 1{sup 10}Ag, {sup 124}Sb, {sup 239}Np, {sup 237}U, {sup 241}Am. (authors) [French] La mesure du nombre d'atomes N d'un isotope peut s'effectuer sur un rayonnement {gamma} si l'on connait le rapport d'embranchement K{sub E} (nombre de rayonnements {gamma} d'energie E/nombre de desintegrations). N = A/{lambda} N{sub {gamma}}{sub E} / (K{sub E} * {lambda}) La mesure s'effectue en geometrie definie; les rayonnements {gamma} emis par la source sous mylar sont detectes par un cristal INa etalonne en fonction de l'energie, lequel est relie a un photomultiplicateur delivrant des impulsions electriques qui seront analysees par un selecteur multicanaux. La connaissance de la distribution theorique (effet photoelectrique, compton, paires, retrodiffusion, echappement... ) permet de determiner qualitativement si les elements sont purs, et de faire une mesure sur

Mass spectrometry applied to high temperature chemistry, (2)

International Nuclear Information System (INIS)

Asano, Mitsuru; Kato, Eiichi; Sata, Toshiyuki.

1980-01-01

The application of mass spectrometry to high temperature chemistry is reviewed. As a blanket material for fusion reactors, the behavior of lithium has been investigated by using mass analysers. The enthalpies of the chemical reactions of metallic lithium were obtained. The enthalpies of isomolecular exchange reactions and the derived atomization energies of LiD, Li 2 D and Li 2 D 2 were also obtained by mass spectrometry. The thermomechanical character of lithium oxide was studied. The vaporization behaviors of LiCrO 2 and Li 5 FeO 4 were studied with a quadrupole mass analyser. The vaporization of cobalt from nickel alloy was studied. The evaporated ions were analysed with a mass analyser. The measurement of the vaporized molecules of metals and fused silicate was made by mass spectrometry. The activities of Fe-V system were determined by measuring the ion current ratio. The activities of Fe-V-Cr system were also obtained. The vapor pressure of phosphor from Fe-P alloys can be measured. The activity coefficients and interaction parameters for the dilute solutions of elements, such as Mn, Al, Cu, Cr, Co, Ni, Si, Ti, V, B, Zr, Mo, C, S, and P, dissolved in liquid iron are shown in a table. The activities of NaCl-KCl system were derived by measuring the ion current ratio and by monomer-dimer method. (Kato, T.)

CFD analysis of PAR performance as function of inlet design

International Nuclear Information System (INIS)

Park, Kweonha; Khor, Chong Lee

2016-01-01

Highlights: • The new concept of PAR (passive autocatalytic recombiner) was proposed and analyzed. • Guidance wall was added at the bottom of PAR to enhance the flow rate through the catalyst. • The new concept of PAR was proved to have a better hydrogen removal performance. - Abstract: Passive autocatalytic recombiner (PAR) is very useful hydrogen mitigation measurement. It is widely implemented in the current and advanced light water reactors (ALWRs). The design of the PARs should be optimized for the specific use under severe accident scenarios. Several techniques and innovations have been fused into the PAR, as an effort to increase its efficiency of hydrogen mitigation. This study proposes different concepts of PAR, which applied some changes to the honeycomb catalyst PAR made by the Korea Nuclear Technology (KNT) Inc. Two slices of plate are added to the bottom of PAR model, which intended to act as a reflection wall and promote the gas flow into PAR. Hydrogen volume fraction was given 4 vol. % which tested by KNT to investigate the performance of PAR in different direction gas flow conditions to see maximum hydrogen recombination rate. The new concept of PAR was proved to have a better hydrogen removal performance compared to the original honeycomb catalyst PAR.

CFD analysis of PAR performance as function of inlet design

Energy Technology Data Exchange (ETDEWEB)

Park, Kweonha, E-mail: khpark@kmou.ac.kr [Division of Mechanical and Energy systems Engineering, Korea Maritime University, Dongsam-dong, Yeongdo-gu, Busan 606-791 (Korea, Republic of); Khor, Chong Lee, E-mail: itachi_829@hotmail.com [Department of Mechanical Engineering, Korea Maritime University (Korea, Republic of)

2016-01-15

Highlights: • The new concept of PAR (passive autocatalytic recombiner) was proposed and analyzed. • Guidance wall was added at the bottom of PAR to enhance the flow rate through the catalyst. • The new concept of PAR was proved to have a better hydrogen removal performance. - Abstract: Passive autocatalytic recombiner (PAR) is very useful hydrogen mitigation measurement. It is widely implemented in the current and advanced light water reactors (ALWRs). The design of the PARs should be optimized for the specific use under severe accident scenarios. Several techniques and innovations have been fused into the PAR, as an effort to increase its efficiency of hydrogen mitigation. This study proposes different concepts of PAR, which applied some changes to the honeycomb catalyst PAR made by the Korea Nuclear Technology (KNT) Inc. Two slices of plate are added to the bottom of PAR model, which intended to act as a reflection wall and promote the gas flow into PAR. Hydrogen volume fraction was given 4 vol. % which tested by KNT to investigate the performance of PAR in different direction gas flow conditions to see maximum hydrogen recombination rate. The new concept of PAR was proved to have a better hydrogen removal performance compared to the original honeycomb catalyst PAR.

Par Pond Fish, Water, and Sediment Chemistry

International Nuclear Information System (INIS)

Paller, M.H.; Wike, L.D.

1996-06-01

The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond

Par Pond Fish, Water, and Sediment Chemistry

Energy Technology Data Exchange (ETDEWEB)

Paller, M.H. [Westinghouse Savannah River Company, AIKEN, SC (United States); Wike, L.D.

1996-06-01

The objectives of this report are to describe the Par Pond fish community and the impact of the drawdown and refill on the community, describe contaminant levels in Par Pond fish, sediments, and water and indicate how contaminant concentrations and distributions were affected by the drawdown and refill, and predict possible effects of future water level fluctuations in Par Pond.

Accelerator mass spectrometry: state of the art

Energy Technology Data Exchange (ETDEWEB)

Tuniz, C. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

1996-12-31

Accelerator Mass Spectrometry (AMS) is the analytical technique of choice for the detection of long-lived radionuclides which cannot be practically analysed with decay counting or conventional mass spectrometry. The main use of AMS has been in the analysis of radiocarbon and other cosmogenic radionuclides for archaeological, geological and environmental applications. In addition, AMS has been recently applied in biomedicine to study exposure of human tissues to chemicals and biomolecules at attomole levels. There is also a world-wide effort to analyse rare nuclides of heavier masses, such as long-lived actinides, with important applications in safeguards and nuclear waste disposal. The use of AMS is limited by the expensive accelerator technology required and there are several attempts to develop smaller and cheaper AMS spectrometers. 5 refs.

Accelerator mass spectrometry: state of the art

Energy Technology Data Exchange (ETDEWEB)

Tuniz, C [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

1997-12-31

Accelerator Mass Spectrometry (AMS) is the analytical technique of choice for the detection of long-lived radionuclides which cannot be practically analysed with decay counting or conventional mass spectrometry. The main use of AMS has been in the analysis of radiocarbon and other cosmogenic radionuclides for archaeological, geological and environmental applications. In addition, AMS has been recently applied in biomedicine to study exposure of human tissues to chemicals and biomolecules at attomole levels. There is also a world-wide effort to analyse rare nuclides of heavier masses, such as long-lived actinides, with important applications in safeguards and nuclear waste disposal. The use of AMS is limited by the expensive accelerator technology required and there are several attempts to develop smaller and cheaper AMS spectrometers. 5 refs.

Concerning the dynamic instability of actin homolog ParM

International Nuclear Information System (INIS)

Popp, David; Yamamoto, Akihiro; Iwasa, Mitsusada; Narita, Akihiro; Maeda, Kayo; Maeda, Yuichiro

2007-01-01

Using in vitro TIRF- and electron-microscopy, we reinvestigated the dynamics of native ParM, a prokaryotic DNA segregation protein and actin homolog. In contrast to a previous study, which used a cysteine ParM mutant, we find that the polymerization process of wild type ATP-ParM filaments consists of a polymerization phase and a subsequent steady state phase, which is dynamically unstable, like that of microtubules. We find that the apparent bidirectional polymerization of ParM, is not due to the intrinsic nature of this filament, but results from ParM forming randomly oriented bundles in the presence of crowding agents. Our results imply, that in the bacterium, ParM filaments spontaneously form bipolar bundles. Due to their intrinsic dynamic instability, ParM bundles can efficiently 'search' the cytoplasmic lumen for DNA, bind it equally well at the bipolar ends and segregate it approximately symmetrically, by the insertion of ParM subunits at either end

First-in-human uPAR PET

DEFF Research Database (Denmark)

Persson, Morten; Skovgaard, Dorthe; Brandt-Larsen, Malene

2015-01-01

A first-in-human clinical trial with Positron Emission Tomography (PET) imaging of the urokinase-type plasminogen activator receptor (uPAR) in patients with breast, prostate and bladder cancer, is described. uPAR is expressed in many types of human cancers and the expression is predictive...... for targeted molecular imaging with PET. The safety, pharmacokinetic, biodistribution profile and radiation dosimetry after a single intravenous dose of (64)Cu-DOTA-AE105 were assessed by serial PET and computed tomography (CT) in 4 prostate, 3 breast and 3 bladder cancer patients. Safety assessment...... of invasion, metastasis and indicates poor prognosis. uPAR PET imaging therefore holds promise to be a new and innovative method for improved cancer diagnosis, staging and individual risk stratification. The uPAR specific peptide AE105 was conjugated to the macrocyclic chelator DOTA and labeled with (64)Cu...

uPAR as anti-cancer target

DEFF Research Database (Denmark)

Lund, Ida K; Illemann, Martin; Thurison, Tine

2011-01-01

, and a potential diagnostic and predictive impact of the different uPAR forms has been reported. Hence, pericellular proteolysis seems to be a suitable target for anti-cancer therapy and numerous approaches have been pursued. Targeting of this process may be achieved by preventing the binding of uPA to u...... using mouse monoclonal antibodies (mAbs) against mouse uPA or uPAR. These reagents will target uPA and uPAR in both stromal cells and cancer cells, and their therapeutic potential can now be assessed in syngenic mouse cancer models....

Traitement de la margine brute d'huile d'olive par distillation suivi de ...

African Journals Online (AJOL)

L'analyse physico-chimique de la margine brute et distillat, montre que ce dernier se caractérise par des abattements très remarquables des composés phénoliques (97%), Demande Chimique en Oxygène (DOC) (92%), Demande Biologique en Oxygène (DBO) (96%), conductivité (99%,) et chlorures (97%). Conclusion et ...

Protease-activated receptor (PAR2, but not PAR1, is involved in collateral formation and anti-inflammatory monocyte polarization in a mouse hind limb ischemia model.

Directory of Open Access Journals (Sweden)

Lisa G van den Hengel

Full Text Available AIMS: In collateral development (i.e. arteriogenesis, mononuclear cells are important and exist as a heterogeneous population consisting of pro-inflammatory and anti-inflammatory/repair-associated cells. Protease-activated receptor (PAR1 and PAR2 are G-protein-coupled receptors that are both expressed by mononuclear cells and are involved in pro-inflammatory reactions, while PAR2 also plays a role in repair-associated responses. Here, we investigated the physiological role of PAR1 and PAR2 in arteriogenesis in a murine hind limb ischemia model. METHODS AND RESULTS: PAR1-deficient (PAR1-/-, PAR2-deficient (PAR2-/- and wild-type (WT mice underwent femoral artery ligation. Laser Doppler measurements revealed reduced post-ischemic blood flow recovery in PAR2-/- hind limbs when compared to WT, while PAR1-/- mice were not affected. Upon ischemia, reduced numbers of smooth muscle actin (SMA-positive collaterals and CD31-positive capillaries were found in PAR2-/- mice when compared to WT mice, whereas these parameters in PAR1-/- mice did not differ from WT mice. The pool of circulating repair-associated (Ly6C-low monocytes and the number of repair-associated (CD206-positive macrophages surrounding collaterals in the hind limbs were increased in WT and PAR1-/- mice, but unaffected in PAR2-/- mice. The number of repair-associated macrophages in PAR2-/- hind limbs correlated with CD11b- and CD115-expression on the circulating monocytes in these animals, suggesting that monocyte extravasation and M-CSF-dependent differentiation into repair-associated cells are hampered. CONCLUSION: PAR2, but not PAR1, is involved in arteriogenesis and promotes the repair-associated response in ischemic tissues. Therefore, PAR2 potentially forms a new pro-arteriogenic target in coronary artery disease (CAD patients.

Routine Isotopic Analysis of {sup 235}U by Emission Spectrometry. 1. Interferometry using electrode-less discharge lamps 2. determination of the {sup 235}U/{sup 238}U ratio using a spectrograph and electrode-less lamps; Contribution a l'analyse isotopique de routine de l'uranium 235 par spectrometrie d'emission. 1. interferometrie avec des lampes a decharge sans electrode. 2. determination du rapport {sup 235}U/{sup 238}U a l'aide d'un spectrographe et avec des lampes sans electrodes

Energy Technology Data Exchange (ETDEWEB)

Capitini, R; Ceccaldi, M; Leicknam, J P; Rabec, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1970-07-01

{+-} 2 a 3 pour cent; pour des echantillons enrichis en uranium 235 (5 a 93 pour cent), la precision relative atteint {+-} 0.5 pour cent. II. Malgre le tres grand nombre de travaux effectues pour ameliorer la precision des analyses isotopiques de l'uranium par voie optique, il n'a jusqu'a present pas ete possible de mettre au point une methode permettant de concurrencer la spectrometrie de masse. Cependant, lorsqu'on n'a pas besoin d'une tres grande precision, la spectrometrie d'emission, qui ne presente pas d'effet de memoire, peut constituer une methode d'analyse complementaire, si elle est suffisamment rapide et economique; pour qu'il en soit ainsi, il nous semble qu'une telle methode doit pouvoir etre appliquee dans les laboratoires equipes d'appareils d'analyses spectrochimiques courants. (auteur) [abstract truncated

Analyse quantitative détaillée des distillats moyens par couplage CG/SM. Application à l'étude des schémas réactionnels du procédé d'hydrotraitement Quantitative Analysis of Middle Distillats by Gc/Ms Coupling. Application to Hydrotreatment Process Mechanisms

Directory of Open Access Journals (Sweden)

Fafet A.

2006-11-01

Full Text Available L'analyse détaillée des distillats moyens est une étape indispensable à la compréhension des mécanismes réactionnels et à la cinétique de certains procédés de raffinage comme l'hydrotraitement. Une nouvelle méthode associant, d'une part un couplage chromatographie en phase gazeuse/spectrométrie de masse (CG/SM et, d'autre part une analyse quantitative par famille chimique par spectrométrie de masse a été développée. La chromatographie en phase gazeuse, réalisée sur une colonne apolaire, effectue la distillation des composés présents dans le gazole et la spectrométrie de masse quantifie les familles chimiques par intervalle de nombre d'atomes de carbone ou de point d'ébullition. Elle permet d'accéder ainsi à la répartition par nombre d'atomes de carbone de chaque famille chimique (alcanes, cycloalcanes, hydrocarbures aromatiques à un ou plusieurs noyaux, hydrocarbures aromatiques soufrés. Cette méthode a été validée et appliquée à une charge et à une recette d'hydrotraitement. A detailed analysis of middle distillates is essential for understanding the reaction mechanism and for studying the kinetics of refining processes such hydrotreatment. In fact, when we see the complexity of saturated and aromatic hydrocarbon mixtures appearing in gas oil, we realize that it's necessary to have a very detailed analysis of those cuts to understand the mechanisms involved in refining processes and to be able to describe their kinetics. Each gas oil has a very different composition and therefore a specific reactivity. That is why we have tried to develop predictive kinetic models to avoid experimenting in pilot plants, which is very expensive. But, even if all the compounds of a gasoline (PI-200°C have now been identified and quantified, using gas chromatography (1, such is not the case for heavier cuts. Only an overall characterization can be made, by chemical family. The techniques employed are, for example, HPLC (3,4 or

Apoplejía pituitaria con parálisis del III par craneal: Reporte de caso

Directory of Open Access Journals (Sweden)

Miguel Pinto Valdivia

2011-10-01

Full Text Available Se describe el caso de un varón de 65 años de edad, sin antecedentes patológicos de importancia, que acudió a emergencia del Hospital Nacional Cayetano Heredia por presentar cefalea intensa y ptosis palpebral izquierda. El examen físico mostró parálisis aislada del III par craneal izquierdo. Los análisis de laboratorio mostraron hiponatremia e hipopituitarismo y la resonancia magnética nuclear un adenoma pituitario con áreas de hemorragia e invasión de los senos cavernosos. El tratamiento incluyó glucocorticoides y descompresión quirúrgica transesfenoidal. La anatomía patológica confirmó el diagnóstico de infarto hemorrágico de un adenoma pituitario. El paciente fue dado de alta con terapia sustitutiva de levotiroxina y prednisona. La ptosis palpebral izquierda se recuperó en forma parcial. La apoplejía pituitaria es un síndrome clínico producido por un proceso expansivo dentro de la silla turca, secundario a hemorragia o infarto de un adenoma pituitario, que se caracteriza por cefalea, déficit visual, oftalmoplejía y alteración del nivel de conciencia. Este proceso expansivo puede comprimir los pares craneales en los senos cavernosos, produciendo diferentes grados de parálisis de los músculos oculomotores. La parálisis aislada del III par craneal es rara.(Rev Med Hered 2011;22:186-189.

Copenhagen uPAR prostate cancer (CuPCa) database

DEFF Research Database (Denmark)

Lippert, Solvej; Berg, Kasper D; Høyer-Hansen, Gunilla

2016-01-01

AIM: Urokinase plasminogen activator receptor (uPAR) plays a central role during cancer invasion by facilitating pericellular proteolysis. We initiated the prospective 'Copenhagen uPAR Prostate Cancer' study to investigate the significance of uPAR levels in prostate cancer (PCa) patients. METHODS...

Recombination in the human Pseudoautosomal region PAR1.

Directory of Open Access Journals (Sweden)

Anjali G Hinch

2014-07-01

Full Text Available The pseudoautosomal region (PAR is a short region of homology between the mammalian X and Y chromosomes, which has undergone rapid evolution. A crossover in the PAR is essential for the proper disjunction of X and Y chromosomes in male meiosis, and PAR deletion results in male sterility. This leads the human PAR with the obligatory crossover, PAR1, to having an exceptionally high male crossover rate, which is 17-fold higher than the genome-wide average. However, the mechanism by which this obligatory crossover occurs remains unknown, as does the fine-scale positioning of crossovers across this region. Recent research in mice has suggested that crossovers in PAR may be mediated independently of the protein PRDM9, which localises virtually all crossovers in the autosomes. To investigate recombination in this region, we construct the most fine-scale genetic map containing directly observed crossovers to date using African-American pedigrees. We leverage recombination rates inferred from the breakdown of linkage disequilibrium in human populations and investigate the signatures of DNA evolution due to recombination. Further, we identify direct PRDM9 binding sites using ChIP-seq in human cells. Using these independent lines of evidence, we show that, in contrast with mouse, PRDM9 does localise peaks of recombination in the human PAR1. We find that recombination is a far more rapid and intense driver of sequence evolution in PAR1 than it is on the autosomes. We also show that PAR1 hotspot activities differ significantly among human populations. Finally, we find evidence that PAR1 hotspot positions have changed between human and chimpanzee, with no evidence of sharing among the hottest hotspots. We anticipate that the genetic maps built and validated in this work will aid research on this vital and fascinating region of the genome.

Comparison of photoacoustic radiometry to gas chromatography/mass spectrometry methods for monitoring chlorinated hydrocarbons

International Nuclear Information System (INIS)

Sollid, J.E.; Trujillo, V.L.; Limback, S.P.; Woloshun, K.A.

1996-01-01

A comparison of two methods of gas chromatography mass spectrometry (GCMS) and a nondispersive infrared technique, photoacoustic radiometry (PAR), is presented in the context of field monitoring a disposal site. First is presented an historical account describing the site and early monitoring to provide an overview. The intent and nature of the monitoring program changed when it was proposed to expand the Radiological Waste Site close to the Hazardous Waste Site. Both the sampling methods and analysis techniques were refined in the course of this exercise

Plasma suPAR is lowered by smoking cessation

DEFF Research Database (Denmark)

Eugen-Olsen, Jesper; Ladelund, Steen; Sørensen, Lars Tue

2016-01-01

BACKGROUND: Soluble urokinase plasminogen activator receptor (suPAR) is a stable inflammatory biomarker. In patients, suPAR is a marker of disease presence, severity and prognosis. In the general population, suPAR is predictive of disease development, such as diabetes and cardiovascular disease a...

Measurement and analysis of high energy radiation through activation detectors. Application in dosimetry; Sur la mesure et l'analyse des rayonnements de haute energie par detecteurs a activation. Application a la dosimetrie

Energy Technology Data Exchange (ETDEWEB)

Sklavenitis, L. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-10-15

detecteurs, une etude systematique des reactions nucleaires a tres haute energie est realisee ainsi que la mesure et le calcul des sections efficaces d'un certain nombre de reactions, comme la reaction {sup 11}B (p,n) {sup 11}C entre 150 et 3000 MeV et la reaction {sup 34}S (p,2pn) {sup 32}P entre 50 et 3000 MeV. La deuxieme partie est relative a l'application de l'analyse des fluences dans un fantome equivalent aux tissus irradie par des protons de 3 GeV. Cette analyse est suffisamment detaillee pour permettre de reconstituer les doses absorbees, les equivalents de dose et, sous reserve d'une meilleure connaissance de la dose due aux particules lourdes, les facteurs de qualite. Elle a permis, par ailleurs, de suivre l'evolution des differentes donnees dosimetriques en fonction de la profondeur dans le fantome et d'effectuer une verification des calculs deja faits par d'autres chercheurs. La comparaison des doses mesurees et des activites correspondantes de certains detecteurs a revele une qualite de ces derniers pouvant eventuellement conduire a la mise au point d'un detecteur qui donnerait directement la dose absorbee ou meme l'equivalent de dose par simple mesure de son activite. (auteur)

Study of a micro-sublimation apparatus with removal of the vapours by pumping; application to the analysis of fluorinated products (1963); Etude d'un appareillage de microsublimation avec entrainement des vapeurs par pompage et application a l'analyse des produits fluores (1963)

Energy Technology Data Exchange (ETDEWEB)

Delvalle, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1963-07-01

Micro-sublimation analysis presents definite advantages both from the qualitative and quantitative points of view. An automatic micro-sublimation analysis apparatus has been developed for the analysis of fluorinated products (ClF{sub 3}, HF, UF{sub 6}, etc.) but this is only one particular application of a method which has a far wider field of possible applications. We give first the most favorable conditions for the operation of such an apparatus. These conditions are the use of a detector which is linear and independent of the nature of the gas, the flow of the sublimed vapours in the conditions of molecular flow, and finally a reproducible and linear re-heating of the separating trap. The apparatus thus built has the advantage of yielding any analysis without prior calibration. It also makes possible the easy identification of an unknown product by the determination of its vapour pressure curve and its molecular weight. The analysis of fluorinated products with this apparatus has shown that the experimental results agree well with what is expected. (author) [French] L'analyse par microsublimation presente un interet certain tant au point de vue qualitatif que quantitatif. Nous avons mis au point un appareillage automatique d'analyse par microsublimation pour l'analyse des produits fluores (CIF{sub 3}, HF, UF{sub 6}, etc.) mais il ne s'agit que de l'application a un cas particulier d'une methode ayant un champ d'applications bien plus vaste. Nous exposons tout d'abord les conditions les plus favorables au bon fonctionnement d'un tel appareil. Ces conditions sont l'emploi d'un detecteur lineaire et independant de la nature du gaz, l'ecoulement des vapeurs sublimees en regime moleculaire et enfin un rechauffage reproductible et lineaire du piege separateur. L'appareil ainsi realise presente l'avantage d'effectuer une analyse quelconque sans etalonnage prealable. Il permet en outre d'identifier aisement un corps inconnu par la determination de sa courbe de tension

Accounting for undetected compounds in statistical analyses of mass spectrometry 'omic studies.

Science.gov (United States)

Taylor, Sandra L; Leiserowitz, Gary S; Kim, Kyoungmi

2013-12-01

Mass spectrometry is an important high-throughput technique for profiling small molecular compounds in biological samples and is widely used to identify potential diagnostic and prognostic compounds associated with disease. Commonly, this data generated by mass spectrometry has many missing values resulting when a compound is absent from a sample or is present but at a concentration below the detection limit. Several strategies are available for statistically analyzing data with missing values. The accelerated failure time (AFT) model assumes all missing values result from censoring below a detection limit. Under a mixture model, missing values can result from a combination of censoring and the absence of a compound. We compare power and estimation of a mixture model to an AFT model. Based on simulated data, we found the AFT model to have greater power to detect differences in means and point mass proportions between groups. However, the AFT model yielded biased estimates with the bias increasing as the proportion of observations in the point mass increased while estimates were unbiased with the mixture model except if all missing observations came from censoring. These findings suggest using the AFT model for hypothesis testing and mixture model for estimation. We demonstrated this approach through application to glycomics data of serum samples from women with ovarian cancer and matched controls.

The inflammatory marker suPAR after cardiac arrest

DEFF Research Database (Denmark)

Rundgren, Malin; Lyngbaek, Stig; Fisker, Helle

2015-01-01

. This pilot study aimed at investigating suPAR levels in relation to outcome after CA and mild induced hypothermia. METHODS: suPAR levels were measured at 6, 36, and 72 hours in patients treated with hypothermia after CA. suPAR levels were analyzed in relation to survival after 6 months. Receiver operating...

Par Pond phytoplankton in association with refilling of the pond: Final Report for sampling from February 1995 -- September 1996

International Nuclear Information System (INIS)

Wilde, E.W.; Johnson, M.A.; Cody, W.C.

1996-01-01

This report describes the results of phytoplankton analyses from Par Pond samples collected between February 1995 and September 1996. The principal objective of the study was to determine the effect of refilling of Par Pond following repair of the dam on the phytoplankton community. Algal blooms are often responsible for fish kills and other detrimental effects in ponds and lakes, and it was postulated that decaying vegetation from formerly exposed sediments might trigger algal blooms that could result in fish kills in Par Pond following the refill. Sporadic algal blooms involving blue-green algae were detected, especially during the summer of 1996. However, the data derived from the study demonstrates that overall, the refilling effort caused no significant negative impact to the pond attributable to phytoplankton dynamics

Par Pond phytoplankton in association with refilling of the pond: Final Report for sampling from February 1995 -- September 1996

Energy Technology Data Exchange (ETDEWEB)

Wilde, E.W.; Johnson, M.A.; Cody, W.C.

1996-12-31

This report describes the results of phytoplankton analyses from Par Pond samples collected between February 1995 and September 1996. The principal objective of the study was to determine the effect of refilling of Par Pond following repair of the dam on the phytoplankton community. Algal blooms are often responsible for fish kills and other detrimental effects in ponds and lakes, and it was postulated that decaying vegetation from formerly exposed sediments might trigger algal blooms that could result in fish kills in Par Pond following the refill. Sporadic algal blooms involving blue-green algae were detected, especially during the summer of 1996. However, the data derived from the study demonstrates that overall, the refilling effort caused no significant negative impact to the pond attributable to phytoplankton dynamics.

Qualitative and quantitative analyses of flavonoids in Spirodela polyrrhiza by high-performance liquid chromatography coupled with mass spectrometry.

Science.gov (United States)

Qiao, Xue; He, Wen-ni; Xiang, Cheng; Han, Jian; Wu, Li-jun; Guo, De-an; Ye, Min

2011-01-01

Spirodela polyrrhiza (L.) Schleid. is a traditional Chinese herbal medicine for the treatment of influenza. Despite its wide use in Chinese medicine, no report on quality control of this herb is available so far. To establish qualitative and quantitative analytical methods by high-performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) for the quality control of S. polyrrhiza. The methanol extract of S. polyrrhiza was analysed by HPLC/ESI-MS(n). Flavonoids were identified by comparing with reference standards or according to their MS(n) (n = 2-4) fragmentation behaviours. Based on LC/MS data, a standardised HPLC fingerprint was established by analysing 15 batches of commercial herbal samples. Furthermore, quantitative analysis was conducted by determining five major flavonoids, namely luteolin 8-C-glucoside, apigenin 8-C-glucoside, luteolin 7-O-glucoside, apigenin 7-O-glucoside and luteolin. A total of 18 flavonoids were identified by LC/MS, and 14 of them were reported from this herb for the first time. The HPLC fingerprints contained 10 common peaks, and could differentiate good quality batches from counterfeits. The total contents of five major flavonoids in S. polyrrhiza varied significantly from 4.28 to 19.87 mg/g. Qualitative LC/MS and quantitative HPLC analytical methods were established for the comprehensive quality control of S. polyrrhiza. Copyright © 2011 John Wiley & Sons, Ltd.

It's quicker "Par Avignon"!

CERN Multimedia

2005-01-01

For a few years, the CERN Library has been receiving books from the University of Hanover sent via Avignon, at least that's what it says on the envelope. Such a detour would mean that parcels were travelling 720 km more than the distance separating Geneva and Hanover, which would be a very strange state of affairs. The explanation lies in a spelling mistake. The sender has been stamping parcels with a stamp that says "Par Avignon prioritaire" (first-class via Avignon) instead of "Par Avion prioritaire" (First Class Air Mail), a source of much amusement to the librarians!

Serum suPAR in patients with FSGS: trash or treasure?

Science.gov (United States)

Maas, Rutger J H; Deegens, Jeroen K J; Wetzels, Jack F M

2013-07-01

The urokinase-type plasminogen activator receptor (uPAR) has important functions in cell migration. uPAR can be shed from the cell membrane resulting in soluble uPAR (suPAR). Further cleavage gives rise to shorter fragments with largely unknown functions. Recent studies have demonstrated that both overexpression of uPAR on podocytes and the administration of suPAR cause proteinuria in mice. The common pathogenic mechanism involves the activation of podocyte β3-integrin. Increased activation of β3-integrin is also observed in patients with focal and segmental glomerulosclerosis (FSGS). These observations form the basis for the hypothesis that suPAR may be the circulating factor causing FSGS. A recent study fosters this idea by demonstrating increased suPAR levels in the serum of patients with FSGS and reporting an association with recurrence after transplantation and response to plasmapheresis. However, this study was heavily biased, and subsequent studies have given conflicting results. Although the experimental work is very suggestive, at present there is no proof that any known human suPAR fragment causes FSGS in humans. We therefore suggest that the measurement of suPAR using currently available assays has absolutely no value at the present time in decision-making in routine clinical practice.

Proteinase-Activated Receptor 1 (PAR1 regulates leukemic stem cell functions.

Directory of Open Access Journals (Sweden)

Nicole Bäumer

Full Text Available External signals that are mediated by specific receptors determine stem cell fate. The thrombin receptor PAR1 plays an important role in haemostasis, thrombosis and vascular biology, but also in tumor biology and angiogenesis. Its expression and function in hematopoietic stem cells is largely unknown. Here, we analyzed expression and function of PAR1 in primary hematopoietic cells and their leukemic counterparts. AML patients' blast cells expressed much lower levels of PAR1 mRNA and protein than CD34+ progenitor cells. Constitutive Par1-deficiency in adult mice did not affect engraftment or stem cell potential of hematopoietic cells. To model an AML with Par1-deficiency, we retrovirally introduced the oncogene MLL-AF9 in wild type and Par1-/- hematopoietic progenitor cells. Par1-deficiency did not alter initial leukemia development. However, the loss of Par1 enhanced leukemic stem cell function in vitro and in vivo. Re-expression of PAR1 in Par1-/- leukemic stem cells delayed leukemogenesis in vivo. These data indicate that Par1 contributes to leukemic stem cell maintenance.

Proteinase-Activated Receptor 1 (PAR1) regulates leukemic stem cell functions.

Science.gov (United States)

Bäumer, Nicole; Krause, Annika; Köhler, Gabriele; Lettermann, Stephanie; Evers, Georg; Hascher, Antje; Bäumer, Sebastian; Berdel, Wolfgang E; Müller-Tidow, Carsten; Tickenbrock, Lara

2014-01-01

External signals that are mediated by specific receptors determine stem cell fate. The thrombin receptor PAR1 plays an important role in haemostasis, thrombosis and vascular biology, but also in tumor biology and angiogenesis. Its expression and function in hematopoietic stem cells is largely unknown. Here, we analyzed expression and function of PAR1 in primary hematopoietic cells and their leukemic counterparts. AML patients' blast cells expressed much lower levels of PAR1 mRNA and protein than CD34+ progenitor cells. Constitutive Par1-deficiency in adult mice did not affect engraftment or stem cell potential of hematopoietic cells. To model an AML with Par1-deficiency, we retrovirally introduced the oncogene MLL-AF9 in wild type and Par1-/- hematopoietic progenitor cells. Par1-deficiency did not alter initial leukemia development. However, the loss of Par1 enhanced leukemic stem cell function in vitro and in vivo. Re-expression of PAR1 in Par1-/- leukemic stem cells delayed leukemogenesis in vivo. These data indicate that Par1 contributes to leukemic stem cell maintenance.

The prognostic value of the suPARnosticTM ELISA assay in HIV-1 infected individuals is not affected by uPAR promoter polymorphisms

DEFF Research Database (Denmark)

Schneider, Uffe; Nielsen, Rikke; Pedersen, Court

2007-01-01

. METHODS: DNA samples were collected retrospectively from 145 Danes infected with HIV-1 with known seroconversion times. In addition, plasma was collected retrospectively from 81 of these participants for use in the suPAR analysis. Survival was analysed using Kaplan Meier analysis. RESULTS: Survival...... to A transition at -118 and an A to G transition at -465 comparative to the transcription start site. These promoter transitions did not influence neither the suPAR levels nor patient survival. CONCLUSION: Plasma suPAR levels, as measured by the suPARnosticTM assay, were strongly predictive of survival in ART...

Serum suPAR in patients with FSGS: trash or treasure?

NARCIS (Netherlands)

Maas, R.J.H.; Deegens, J.K.J.; Wetzels, J.F.M.

2013-01-01

The urokinase-type plasminogen activator receptor (uPAR) has important functions in cell migration. uPAR can be shed from the cell membrane resulting in soluble uPAR (suPAR). Further cleavage gives rise to shorter fragments with largely unknown functions. Recent studies have demonstrated that both

Characterization of pars intermedia connections in amphibians by biocytin tract tracing and immunofluorescence aided by confocal microscopy

NARCIS (Netherlands)

Jansen, K; Fabro, C; Artero, C; Feuilloley, M; Vaudry, H; Fasolo, A; Franzoni, MF

Biocytin, recently introduced in neuroanatomical studies, was used as a retrograde tract tracer in combination with immunofluorescence in order to analyse the neurochemical characters of some central neuronal projections to the pars intermedia in two amphibian species, the anuran Rana esculenta and

Accouchement par forceps: indications et pronostic materno-foetal ...

African Journals Online (AJOL)

L'accouchement par voie basse, peut être parfois compromis par des facteurs maternels, foetaux ou materno-foetaux nécessitant des moyens thérapeutiques comme le forceps pour achever l'accouchement par voie naturelle. Le forceps, une méthode qui n'est pas sans risque pour la mère et le nouveau-né. Nous avons ...

Isotopic analysis using optical spectroscopy (1963); Analyse isotopique par spectroscopie optique (1963)

Energy Technology Data Exchange (ETDEWEB)

Gerstenkorn, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1963-07-01

The isotopic displacement in the atomic lines of certain elements (H, He, Li, Ne, Sr, Hg, Pb, U, Pu) is used for dosing these elements isotopically. The use of the Fabry-Perot photo-electric interference spectrometer is shown to be particularly adapted for this sort of problem: in each case we give on the one hand the essential results obtained with this apparatus, and on the other hand the results previously obtained with a conventional apparatus (grating, photographic plate). These results together give an idea of the possibilities of optical spectroscopy: in the best case, the precision which may be expected is of the order of 1 to 2 per cent for isotopes whose concentration is about 1 per cent. (author) [French] Le deplacement isotopique dans les raies atomiques de certains elements (H, He, Li, Ne, Sr, Hg, Pb, U, Pu) est utilise pour effectuer le dosage isotopique de ces elements. L'utilisation du spectrometre interferentiel Fabry-Perot photoelectrique se revele particulierement adapte a ce genre de probleme: dans chaque cas, nous donnons d'une part l'essentiel des resultats obtenus avec cet appareil, et d'autre part, les resultats obtenus anterieurement a l'aide de l'appareillage classique (reseau, plaque photographique). L'ensemble de ces informations donne une idee des possibilites offertes par la spectroscopie optique: dans le meilleur des cas, la precision que l'on peut esperer est de l'ordre de 1 a 2 pour cent pour des isotopes dont la concentration est de l'ordre de 1 pour cent. (auteur)

Total and species-specific quantitative analyses of trace elements in sediment by isotope dilution inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Inagaki, Kazumi; Takatsu, Akiko; Yarita, Takashi; Okamoto, Kensaku; Chiba, Koichi

2009-01-01

Isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) is one of the reliable methods for total and species-specific quantitative analysis of trace elements. However, several technical problems (e.g. spectral interference caused from sample constituents) should be overcome to obtain reliable analytical results when environmental samples are analyzed by ID-ICP-MS. In our laboratory, various methods based on ID-ICP-MS have been investigated for reliable quantitative analyses of trace elements in environmental samples. In this paper, coprecipitate separation/ID-ICP-MS for the determination of trace elements in sediment, cation exchange disk filtration/ID-ICP-MS for the determination of selenium in sediment, species-specific ID-ICP-MS using 118 Sn/labeled organotin compounds for the determination of butyltins and phenyltins, and the application of the ID-ICP-MS methods to the certification of sediment reference materials are described. (author)

Evaluation of passive autocatalytic recombiners (PARS) performance for a PWR-konvoi containment type with Gothic 8.1 code; Evaluacion de la implementacion de recombinadores autocataliticos pasivos (PAR) en una contencion tipo Konvoi con el codigo Gothic 8.1

Energy Technology Data Exchange (ETDEWEB)

Lopez-Alonso Conty, E.; Papini, D.; Jimenez Varas, G.

2016-08-01

The study presented in this work analyses the evaluation of Passive Autocatalytic Recombiners (PARs) performance for a PWR-Konvoi containment type as a result of an international collaboration between the Paul Scherrer institute (PSI) and the Universidad Politecnica de Madrid (UPM). The implementation study analyzes the size, location and number of the PARs to minimize the risk arising from a hydrogen release and its distribution in the containment building during a hypothetical severe accident. A detailed 3D model of containment was used for the simulations developed for the Gothic 8.1 code. In the first place, the hydrogen preferential pathways and points of hydrogen accumulation were studies and identified starting from the base case scenario without any mitigation measure. The severe accident scenario chosen is a fast release of hydrogen-steam mixture from hot leg creep rupture during SBO (Station Black-Out) accident. Secondly a configuration of PARs was simulated under the same conditions of the unmitigated case. The PAR configuration offered an improvement in the chosen accident scenario, decreasing the hydrogen concentration values below the flammability limit /hydrogen concentration below 7%) in all the containment compartments. (Author)

Pratique de l'analyse fonctionelle

CERN Document Server

Tassinari, Robert

1997-01-01

Mettre au point un produit ou un service qui soit parfaitement adapté aux besoins et aux exigences du client est indispensable pour l'entreprise. Pour ne rien laisser au hasard, il s'agit de suivre une méthodologie rigoureuse : celle de l'analyse fonctionnelle. Cet ouvrage définit précisément cette méthode ainsi que ses champs d'application. Il décrit les méthodes les plus performantes en termes de conception de produit et de recherche de qualité et introduit la notion d'analyse fonctionnelle interne. Un ouvrage clé pour optimiser les processus de conception de produit dans son entreprise. -- Idées clés, par Business Digest

Plasma levels of intact and cleaved urokinase plasminogen activator receptor (uPAR) in men with clinically localised prostate cancer

DEFF Research Database (Denmark)

Kristensen, Gitte; Berg, Kasper Drimer; Lippert, Solvej

2017-01-01

Aims: Lymph node metastasis (N1) is an adverse prognostic factor for men with clinically localised prostate cancer (PCa), but the prediction of N1 disease remains difficult. Urokinase plasminogen activator receptor (uPAR) plays an important role in angiogenesis and tumorigenesis. We analysed...... analysis and quantified using the areas under the ROC curve (AUC).Results: All soluble uPAR levels were significantly (p=0.03) higher in patients with N1 disease compared with patients with N0/x disease. ROC curves including clinical tumour stage, biopsy Gleason score, prostate-specific antigen and percent...

Protease-Activated Receptor 4 (PAR4): A Promising Target for Antiplatelet Therapy.

Science.gov (United States)

Rwibasira Rudinga, Gamariel; Khan, Ghulam Jilany; Kong, Yi

2018-02-14

Cardiovascular diseases (CVDs) are currently among the leading causes of death worldwide. Platelet aggregation is a key cellular component of arterial thrombi and major cause of CVDs. Protease-activated receptors (PARs), including PAR1, PAR2, PAR3 and PAR4, fall within a subfamily of seven-transmembrane G-protein-coupled receptors (GPCR). Human platelets express PAR1 and PAR4, which contribute to the signaling transduction processes. In association with CVDs, PAR4 not only contributes to platelet activation but also is a modulator of cellular responses that serve as hallmarks of inflammation. Although several antiplatelet drugs are available on the market, they have many side effects that limit their use. Emerging evidence shows that PAR4 targeting is a safer strategy for preventing thrombosis and consequently may improve the overall cardiac safety profile. Our present review summarizes the PAR4 structural characteristics, activation mechanism, role in the pathophysiology of diseases and understanding the association of PAR4 targeting for improved cardiac protection. Conclusively, this review highlights the importance of PAR4 antagonists and its potential utility in different CVDs.

Functional and gene network analyses of transcriptional signatures characterizing pre-weaned bovine mammary parenchyma or fat pad uncovered novel inter-tissue signaling networks during development

Directory of Open Access Journals (Sweden)

Lewin Harris A

2010-05-01

Full Text Available Abstract Background The neonatal bovine mammary fat pad (MFP surrounding the mammary parenchyma (PAR is thought to exert proliferative effects on the PAR through secretion of local modulators of growth induced by systemic hormones. We used bioinformatics to characterize transcriptomics differences between PAR and MFP from ~65 d old Holstein heifers. Data were mined to uncover potential crosstalk through the analyses of signaling molecules preferentially expressed in one tissue relative to the other. Results Over 9,000 differentially expressed genes (DEG; False discovery rate ≤ 0.05 were found of which 1,478 had a ≥1.5-fold difference between PAR and MFP. Within the DEG highly-expressed in PAR vs. MFP (n = 736 we noted significant enrichment of functions related to cell cycle, structural organization, signaling, and DNA/RNA metabolism. Only actin cytoskeletal signaling was significant among canonical pathways. DEG more highly-expressed in MFP vs. PAR (n = 742 belong to lipid metabolism, signaling, cell movement, and immune-related functions. Canonical pathways associated with metabolism and signaling, particularly immune- and metabolism-related were significantly-enriched. Network analysis uncovered a central role of MYC, TP53, and CTNNB1 in controlling expression of DEG highly-expressed in PAR vs. MFP. Similar analysis suggested a central role for PPARG, KLF2, EGR2, and EPAS1 in regulating expression of more highly-expressed DEG in MFP vs. PAR. Gene network analyses revealed putative inter-tissue crosstalk between cytokines and growth factors preferentially expressed in one tissue (e.g., ANGPTL1, SPP1, IL1B in PAR vs. MFP; ADIPOQ, IL13, FGF2, LEP in MFP vs. PAR with DEG preferentially expressed in the other tissue, particularly transcription factors or pathways (e.g., MYC, TP53, and actin cytoskeletal signaling in PAR vs. MFP; PPARG and LXR/RXR Signaling in MFP vs. PAR. Conclusions Functional analyses underscored a reciprocal influence in

Gas Well Testing Analysis Using Finite-Difference Models and Optimization Techniques Analyse d'essais de puits de gaz par des modèles utilisant la méthode des différences finies et par des techniques d'optimisation

Directory of Open Access Journals (Sweden)

Darderes E. A.

2006-11-01

paramètres à partir d'essais de puits de gaz. Une des plus performantes est l'analyse du régime pseudo-permanent pour lequel on trouve, sur un graphique semi-logarithmique, une relation linéaire entre la pseudo-pression d'un gaz réel et le temps. Une autre méthode est l'ajustement à des courbes types. Les deux méthodes présentent l'inconvénient de ne pouvoir être rigoureusement appliquées qu'à des cas spécifiques. Cet article expose une méthode générale permettant d'analyser les données des essais de puits par ajustement automatisé des courbes types. Elle est basée sur le meilleur accord d'un modèle numérique avec les données obtenues dans les essais de puits de gaz grâce à des techniques d'optimisation. Le modèle numérique fournit la solution d'une équation différentielle à dérivées partielles du 2e ordre et fortement non linéaire qui régit le flux radial des gaz réels vers un puits de production. L'équation différentielle est résolue par la méthode des différences finies en tenant compte des variations des propriétés des gaz avec la pression. Pour simuler n'importe quel type d'essais de puits de gaz, on impose des conditions initiales et aux limites appropriées. On minimise les différences résiduelles entre les pressions réelles mesurées pendant l'essai et les pressions calculées par la méthode des moindres carrés. On utilise deux techniques d'optimisation pour obtenir la meilleure estimation des paramètres qui minimisent la somme des carrés des résidus : la méthode monovariante de Fibonacci [1] et la méthode polyvariante de Marquardt [1, 2]. On applique ce mode opératoire à des essais de puits menés à un débit constant et à deux débits constants. Les résultats numériques concordent très bien avec les données des essais de puits.

Multichannel amplitude analyser for nuclear spectrometry

International Nuclear Information System (INIS)

Jankovic, S.; Milovanovic, B.

2003-01-01

A multichannel amplitude analyser with 4096 channels was designed. It is based on a fast 12-bit analog-to-digital converter. The intended purpose of the instrument is recording nuclear spectra by means of scintillation detectors. The computer link is established through an opto-isolated serial connection cable, thus reducing instrument sensitivity to disturbances originating from digital circuitry. Refreshing of the data displayed on the screen occurs on every 2.5 seconds. The impulse peak detection is implemented through the differentiation of the amplified input signal, while the synchronization with the data coming from the converter output is established by taking advantage of the internal 'pipeline' structure of the converter itself. The mode of operation of the built-in microcontroller provides that there are no missed impulses, and the simple logic network prevents the initiation of the amplitude reading sequence for the next impulse in case it appears shortly after its precedent. The solution proposed here demonstrated a good performance at a comparatively low manufacturing cost, and is thus suitable for educational purposes (author)

Determination of radium isotopes in environmental samples by gamma spectrometry, liquid scintillation counting and alpha spectrometry: a review of analytical methodology

International Nuclear Information System (INIS)

Jia, Guogang; Jia, Jing

2012-01-01

Radium (Ra) isotopes are important from the viewpoints of radiation protection and environmental protection. Their high toxicity has stimulated the continuing interest in methodology research for determination of Ra isotopes in various media. In this paper, the three most routinely used analytical techniques for Ra isotope determination in biological and environmental samples, i.e. low-background γ-spectrometry, liquid scintillation counting and α-spectrometry, were reviewed, with emphasis on new methodological developments in sample preparation, preconcentration, separation, purification, source preparation and measurement techniques. The accuracy, selectivity, traceability, applicability and minimum detectable activity (MDA) of the three techniques were discussed. It was concluded that the MDA (0.1 mBq L −1 ) of the α-spectrometry technique coupled with chemical separation is about two orders of magnitude lower than that of low-background HPGe γ-spectrometry and LSC techniques. Therefore, when maximum sensitivity is required, the α-spectrometry technique remains the first choice. - Highlights: ► A review is made for determination of Ra isotopes in environmental samples. ► Gamma spectrometry, LSC and a-spectrometry are the main concerned radiometric approach. ► Sample preparation, preconcentration, separation and source preparation are discussed. ► The methods can analyse air, water, seawater, soil, sediment and foodstuffs samples. ► Some new data obtained recently from our laboratory for Ra method study are included.

PAR1 activation affects the neurotrophic properties of Schwann cells.

Science.gov (United States)

Pompili, Elena; Fabrizi, Cinzia; Somma, Francesca; Correani, Virginia; Maras, Bruno; Schininà, Maria Eugenia; Ciraci, Viviana; Artico, Marco; Fornai, Francesco; Fumagalli, Lorenzo

2017-03-01

Protease-activated receptor-1 (PAR1) is the prototypic member of a family of four G-protein-coupled receptors that signal in response to extracellular proteases. In the peripheral nervous system, the expression and/or the role of PARs are still poorly investigated. High PAR1 mRNA expression was found in the rat dorsal root ganglia and the signal intensity of PAR1 mRNA increased in response to sciatic nerve transection. In the sciatic nerve, functional PAR1 receptor was reported at the level of non-compacted Schwann cell myelin microvilli of the nodes of Ranvier. Schwann cells are the principal population of glial cells of the peripheral nervous system which myelinate axons playing an important role during axonal regeneration and remyelination. The present study was undertaken in order to determine if the activation of PAR1 affects the neurotrophic properties of Schwann cells. Our results suggest that the stimulation of PAR1 could potentiate the Schwann cell ability to favour nerve regeneration. In fact, the conditioned medium obtained from Schwann cell cultures challenged with a specific PAR1 activating peptide (PAR1 AP) displays increased neuroprotective and neurotrophic properties with respect to the culture medium from untreated Schwann cells. The proteomic analysis of secreted proteins in untreated and PAR1 AP-treated Schwann cells allowed the identification of factors differentially expressed in the two samples. Some of them (such as macrophage migration inhibitory factor, matrix metalloproteinase-2, decorin, syndecan 4, complement C1r subcomponent, angiogenic factor with G patch and FHA domains 1) appear to be transcriptionally regulated after PAR1 AP treatment as shown by RT-PCR. Copyright © 2017 Elsevier Inc. All rights reserved.

Protease-Activated Receptor 4 (PAR4: A Promising Target for Antiplatelet Therapy

Directory of Open Access Journals (Sweden)

Gamariel Rwibasira Rudinga

2018-02-01

Full Text Available Cardiovascular diseases (CVDs are currently among the leading causes of death worldwide. Platelet aggregation is a key cellular component of arterial thrombi and major cause of CVDs. Protease-activated receptors (PARs, including PAR1, PAR2, PAR3 and PAR4, fall within a subfamily of seven-transmembrane G-protein-coupled receptors (GPCR. Human platelets express PAR1 and PAR4, which contribute to the signaling transduction processes. In association with CVDs, PAR4 not only contributes to platelet activation but also is a modulator of cellular responses that serve as hallmarks of inflammation. Although several antiplatelet drugs are available on the market, they have many side effects that limit their use. Emerging evidence shows that PAR4 targeting is a safer strategy for preventing thrombosis and consequently may improve the overall cardiac safety profile. Our present review summarizes the PAR4 structural characteristics, activation mechanism, role in the pathophysiology of diseases and understanding the association of PAR4 targeting for improved cardiac protection. Conclusively, this review highlights the importance of PAR4 antagonists and its potential utility in different CVDs.

Heavy water standards. Qualitative analyses, sample treating, stocking and manipulation

International Nuclear Information System (INIS)

Pavelescu, M.; Steflea, D.; Mihancea, I.; Varlam, M.; Irimescu, R.

1995-01-01

This paper presents methods and procedures for measuring heavy water concentration, and also sampling, stocking and handling of samples to be analysed. The main concentration analysis methods are: mass spectrometry, for concentrations less then 1%, densitometry, for concentrations within the range 1% - 99% and infrared spectrometry for concentrations above 99%. Procedures of sampling, processing and purification appropriate to these measuring methods were established. 1 Tab

Vote par sondage uniforme incorruptible

OpenAIRE

Blanchard , Nicolas

2016-01-01

International audience; Introduit en 2012 par David Chaum, le vote par sondage uniforme (random-sample voting) est un protocole de vote basé sur un choix d'une sous-population représentative , permettant de limiter les coûts tout en ayant de nombreux avantages, principalement lorsqu'il est couplé a d'autres techniques comme ThreeBallot. Nous analysons un problème de corruptibilité potentielle où les votants peuvent vendre leur vote au plus offrant et proposons une variation du protocole reméd...

Mass spectrometer introduction line: application to the analysis of impurities in uranium hexafluoride; Ligne d'introduction pour spectrometre de masse: application a l'analyse des impuretes contenues dans l'UF{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Besson, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement de physico-chimie, service des isotopes stables, section de spectrometrie de masse

1967-01-01

The continuous mass-spectrometric analysis of impurities in UF{sub 6} is possible industrially if certain conditions imposed by the nature of the gas are respected. The gas introduction line arriving at the spectrometer's source makes it possible to fix the flow-rate, to control the inlet pressure and to selectively destroy the gas containing the impurities. The operational conditions for the line are defined and a description is given of the theoretical and experimental study of the various elements of which it is composed, i.e. the leak valve, the flow-meter, the chemical trap and the servo-mechanism making it possible to regulate and control the gas flow. The dynamic characteristics of the line's various components and the performance of the equipment in the case of the analyses considered are given. (author) [French] L'analyse en continu par spectrometrie de masse des impuretes contenus dans l'UF{sub 6} est possible industriellement moyennant certaines conditions imposees par la nature du gaz. La ligne d'introduction des gaz dans la source du spectrometre permet de regler le debit, de controler la pression d'introduction et de detruire selectivement le gaz porteur d'impuretes. Les conditions de fonctionnement de la ligne etant definies, on decrit l'etude theorique et experimentale des differents elements qui la composent, c'est-a-dire: le robinet a fuite, le debitmetre, le piege chimique et l'ensemble d'asservissement permettant la regulation et le controle du debit. On donne les caracteristiques dynamiques des differents constituants de la ligne et les performances de l'ensemble pour les analyses considerees. (auteur)

The role of pars flaccida in human middle ear sound transmission.

Science.gov (United States)

Aritomo, H; Goode, R L; Gonzalez, J

1988-04-01

The role of the pars flaccida in middle ear sound transmission was studied with the use of twelve otoscopically normal, fresh, human temporal bones. Peak-to-peak umbo displacement in response to a constant sound pressure level at the tympanic membrane was measured with a noncontacting video measuring system capable of repeatable measurements down to 0.2 micron. Measurements were made before and after pars flaccida modifications at 18 frequencies between 100 and 4000 Hz. Four pars flaccida modifications were studied: (1) acoustic insulation of the pars flaccida to the ear canal with a silicone rubber baffle, (2) stiffening the pars flaccida with cyanoacrylate cement, (3) decreasing the tension of the pars flaccida with a nonperforating incision, and (4) perforation of the pars flaccida. All of the modifications (except the perforation) had a minimal effect on umbo displacement; this seems to imply that the pars flaccida has a minor acoustic role in human beings.

Matrix-Assisted Laser Desorption Ionization Mass Spectrometry Imaging for Peptide and Protein Analyses: A Critical Review of On-Tissue Digestion

NARCIS (Netherlands)

Cillero-Pastor, B.; Heeren, R.M.A.

2013-01-01

Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) has established itself among the plethora of mass spectrometry applications. In the biomedical field, MALDI-MSI is being more frequently recognized as a new method for the discovery of biomarkers and targets of

Phylogenetic Analysis Using Protein Mass Spectrometry.

Science.gov (United States)

Ma, Shiyong; Downard, Kevin M; Wong, Jason W H

2017-01-01

Through advances in molecular biology, comparative analysis of DNA sequences is currently the cornerstone in the study of molecular evolution and phylogenetics. Nevertheless, protein mass spectrometry offers some unique opportunities to enable phylogenetic analyses in organisms where DNA may be difficult or costly to obtain. To date, the methods of phylogenetic analysis using protein mass spectrometry can be classified into three categories: (1) de novo protein sequencing followed by classical phylogenetic reconstruction, (2) direct phylogenetic reconstruction using proteolytic peptide mass maps, and (3) mapping of mass spectral data onto classical phylogenetic trees. In this chapter, we provide a brief description of the three methods and the protocol for each method along with relevant tools and algorithms.

Evaluation of passive autocatalytic recombiners (PARS) performance for a PWR-konvoi containment type with Gothic 8.1 code

International Nuclear Information System (INIS)

Lopez-Alonso Conty, E.; Papini, D.; Jimenez Varas, G.

2016-01-01

The study presented in this work analyses the evaluation of Passive Autocatalytic Recombiners (PARs) performance for a PWR-Konvoi containment type as a result of an international collaboration between the Paul Scherrer institute (PSI) and the Universidad Politecnica de Madrid (UPM). The implementation study analyzes the size, location and number of the PARs to minimize the risk arising from a hydrogen release and its distribution in the containment building during a hypothetical severe accident. A detailed 3D model of containment was used for the simulations developed for the Gothic 8.1 code. In the first place, the hydrogen preferential pathways and points of hydrogen accumulation were studies and identified starting from the base case scenario without any mitigation measure. The severe accident scenario chosen is a fast release of hydrogen-steam mixture from hot leg creep rupture during SBO (Station Black-Out) accident. Secondly a configuration of PARs was simulated under the same conditions of the unmitigated case. The PAR configuration offered an improvement in the chosen accident scenario, decreasing the hydrogen concentration values below the flammability limit /hydrogen concentration below 7%) in all the containment compartments. (Author)

Dosing of traces of oxygenated water by polarography; Dosage de traces d'eau oxygenee par polarographie

Energy Technology Data Exchange (ETDEWEB)

Faure, A. M.; Malterre, J.

1960-07-01

As dosing oxygenated water by using polarography has been envisaged within the framework of water purity controls for the Melusine pile, the objective of the authors is here to see whether the polarographic method could be satisfying for routine analyses, and would result in a higher dosing sensitivity. They describe the polarography principle, indicate devices which are used, specify and comment conditions under which polarography is performed [French] Le dosage de l'eau oxygenee par polarographie a ete envisage dans le cadre des controles de purete de l'eau de la pile Melusine. La methode calorimetrique dans les conditions de fonctionnement de Melusine a puissance maxima, avait mis en evidence des teneurs en H{sub 2}O{sub 2} produites par radiolyse de l'eau, inferieures a 20 ppm. Le but de cette etude, a ete de voir si la methode polarographique pouvait donner satisfaction en analyse de routine a ces teneurs la et permettre une plus grande sensibilite de dosage, la colorimetrie se limitant pratiquement a 1 ppm avec une precision de 20 pour cent environ. (auteurs)

Movement and equipositioning of plasmids by ParA filament disassembly

DEFF Research Database (Denmark)

Ringgaard, Simon; van Zon, Jeroen; Howard, Martin

2009-01-01

, plasmids consistently migrate behind disassembling ParA cytoskeletal structures, suggesting that ParA filaments pull plasmids by depolymerization. The perpetual cycles of ParA assembly and disassembly result in continuous relocation of plasmids, which, on time averaging, results in equidistribution...

PAR-1 contributes to the innate immune response during viral infection

Science.gov (United States)

Antoniak, Silvio; Owens, A. Phillip; Baunacke, Martin; Williams, Julie C.; Lee, Rebecca D.; Weithäuser, Alice; Sheridan, Patricia A.; Malz, Ronny; Luyendyk, James P.; Esserman, Denise A.; Trejo, JoAnn; Kirchhofer, Daniel; Blaxall, Burns C.; Pawlinski, Rafal; Beck, Melinda A.; Rauch, Ursula; Mackman, Nigel

2013-01-01

Coagulation is a host defense system that limits the spread of pathogens. Coagulation proteases, such as thrombin, also activate cells by cleaving PARs. In this study, we analyzed the role of PAR-1 in coxsackievirus B3–induced (CVB3-induced) myocarditis and influenza A infection. CVB3-infected Par1–/– mice expressed reduced levels of IFN-β and CXCL10 during the early phase of infection compared with Par1+/+ mice that resulted in higher viral loads and cardiac injury at day 8 after infection. Inhibition of either tissue factor or thrombin in WT mice also significantly increased CVB3 levels in the heart and cardiac injury compared with controls. BM transplantation experiments demonstrated that PAR-1 in nonhematopoietic cells protected mice from CVB3 infection. Transgenic mice overexpressing PAR-1 in cardiomyocytes had reduced CVB3-induced myocarditis. We found that cooperative signaling between PAR-1 and TLR3 in mouse cardiac fibroblasts enhanced activation of p38 and induction of IFN-β and CXCL10 expression. Par1–/– mice also had decreased CXCL10 expression and increased viral levels in the lung after influenza A infection compared with Par1+/+ mice. Our results indicate that the tissue factor/thrombin/PAR-1 pathway enhances IFN-β expression and contributes to the innate immune response during single-stranded RNA viral infection. PMID:23391721

Use of 14 MeV neutrons in activation analysis. Experiments carried out at the Grenoble nuclear research Centre (1963); Utilisation de neutrons de 14 MeV en analyse par activation. Experience realisee au Centre d'etudes nucleaires de Grenoble (1963)

Energy Technology Data Exchange (ETDEWEB)

Auboin, G; Guazzoni, P; Laverlochere, J [Commisariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1963-07-01

The use of 14 MeV neutron irradiation makes it possible to extend the field of application of activation analysis to elements which cannot be activated in nuclear reactors (oxygen, boron, for example) or else to consider the possibility of 'portable' measurement units for routine analyses. With this aim, tests have been carried out for studying the sensitivity and interferences in the case of the dosing of oxygen in eleven different matrices using 150 and 300 kV SAMES accelerators producing 14 MeV neutrons by the reaction {sup 3}H (d, n) {sup 4}He. The sensitivity of the dosage methods for six writer elements has also been studied. The results obtained show that, for a neutron flux of 10{sup 10} n/4{pi}, the sensitivities vary from 100 {mu}g and 1 mg for oxygen in nine matrices (Be, Ta, Nb, Ti, Zr, Fe, Al, Sb, Si) and that it is possible to dose the six elements F, B, Y, Si, N, Al with sensitivities of between 1 an 1000 micrograms. (authors) [French] L'irradiation au moyen de neutrons de 14 MeV permet d'etendre le domaine d'application de l'analyse par activation a des elements non activables en reacteur nucleaire (oxygene, bore, par exemple) ou encore d'envisager des unites de dosage ''portables'' pour des analyses de routine. Dans ce but, des essais ont ete effectues pour etudier les sensibilites et les interferences dans le cas du dosage de l'oxygene dans onze matrices differentes, au moyen d'accelerateurs SAMES 150 et 300 kV. produisant les neutrons de 14 MeV par la reaction {sup 3}H (d, n) {sup 4}He. Des sensibilites de dosage ont egalement ete etudiees pour six autres elements. Les resultats obtenus montrent que, pour un flux de neutrons de 10{sup 10} n /4{pi}, les sensibilites varient entre 100 {mu}g et 1 mg, pour l'oxygene dans neuf matrices (Be, Ta, Nb, Ti, Zr, Fe, Al, Sb, Si) et qu'il est possible de doser les six elements F, B, Y, Si, N, Al avec des sensibilites se situant entre 1 et 1000 microgrammes. (auteurs)

Row orientation effect on UV-B, UV-A and PAR solar irradiation components in vineyards at Tuscany, Italy

Science.gov (United States)

Grifoni, D.; Carreras, G.; Zipoli, G.; Sabatini, F.; Dalla Marta, A.; Orlandini, S.

2008-11-01

Besides playing an essential role in plant photosynthesis, solar radiation is also involved in many other important biological processes. In particular, it has been demonstrated that ultraviolet (UV) solar radiation plays a relevant role in grapevines ( Vitis vinifera) in the production of certain important chemical compounds directly responsible for yield and wine quality. Moreover, the exposure to UV-B radiation (280-320 nm) can affect plant-disease interaction by influencing the behaviour of both pathogen and host. The main objective of this research was to characterise the solar radiative regime of a vineyard, in terms of photosynthetically active radiation (PAR) and UV components. In this analysis, solar spectral UV irradiance components, broadband UV (280-400 nm), spectral UV-B and UV-A (320-400 nm), the biological effective UVBE, as well as the PAR (400-700 nm) component, were all considered. The diurnal patterns of these quantities and the UV-B/PAR and UV-B/UV-A ratios were analysed to investigate the effect of row orientation of the vineyard in combination with solar azimuth and elevation angles. The distribution of PAR and UV irradiance at various heights of the vertical sides of the rows was also studied. The results showed that the highest portion of plants received higher levels of daily radiation, especially the UV-B component. Row orientation of the vines had a pronounced effect on the global PAR received by the two sides of the rows and, to a lesser extent, UV-A and UV-B. When only the diffused component was considered, this geometrical effect was greatly attenuated. UV-B/PAR and UV-A/PAR ratios were also affected, with potential consequences on physiological processes. Because of the high diffusive capacity of the UV-B radiation, the UV-B/PAR ratio was significantly lower on the plant portions exposed to full sunlight than on those in the shade.

Peptide-Based Optical uPAR Imaging for Surgery

DEFF Research Database (Denmark)

Juhl, Karina; Christensen, Anders; Persson, Morten

2016-01-01

Near infrared intra-operative optical imaging is an emerging technique with clear implications for improved cancer surgery by enabling a more distinct delineation of the tumor margins during resection. This modality has the potential to increase the number of patients having a curative radical...... tumor resection. In the present study, a new uPAR-targeted fluorescent probe was developed and the in vivo applicability was evaluated in a human xenograft mouse model. Most human carcinomas express high level of uPAR in the tumor-stromal interface of invasive lesions and uPAR is therefore considered...... an ideal target for intra-operative imaging. Conjugation of the flourophor indocyanine green (ICG) to the uPAR agonist (AE105) provides an optical imaging ligand with sufficiently high receptor affinity to allow for a specific receptor targeting in vivo. For in vivo testing, human glioblastoma xenograft...

Évaluation du niveau de pollution par les métaux lourds des lacs ...

African Journals Online (AJOL)

La présente étude a pour objectif principal d'évaluer le niveau de pollution métallique des lacs Bini et Dang (Ngaoundéré, Cameroun) à travers l'analyse des eaux et des sédiments de surface. La concentration des métaux lourds (Ni, Cr, Fe, Pb, Cd, Zn) a été mesurée par spectrophotométrie d'absorption atomique.

Radio Column Chromatographic Assay of H{sup 3}-Labelled Substances; Analyse par radiochromatographie en colonne, de substances marquees par le tritium; Radiokhromatograficheskoe ispytanie mechennykh tritiem veshchestv na kolonke; Analisis por radiocromatografia en columna de sustancias marcadas con {sup 3}H

Energy Technology Data Exchange (ETDEWEB)

Scharpenseel, H W; Menke, K H [Institute of Soil Science and Institute of Animal Husbandry, Bonn University, Bonn (Germany)

1962-01-15

between the analyser- and monitor-phototubes. In order to ensure a laminar flow and constantly mixed volume ratio, dose-pumps are lised for the supply of buffer on the column and of the 30-fold volume of toluene/ethanol. The counting efficiency for H{sup 3} averages 2.5-4% for'coils spreading over the whole diameter of the phototubes. 3. The aqeous column effluent is led through an anthracene-filled glass tube and the H{sup 3} counted with close to l{sup o}/o efficiency. (author) [French] Dans la majorite des cas, les recherches radiochromatographique s combinees portant sur des substances marquees par {sup 3}H font partie integrante des experiences biochimiques utilisant des composes trities. Avec un ensemble comprenant un compteur a balayage continu sans fenetre, le comptage du tritium par radiochromatographi e sur papier est d'un rendement de 0,5 a 1,5%, qui depend dans une large mesure de l'epaisseur du papier et de l'autoabsorption dans le compose marque. La radiochromatographie en phase gazeuse des composes trities ne presente pas davantage de difficultes serieuses. On utilise avec succes un ensemble de chromatographic en phase gazeuse comportant une chambre d'ionisation a courant et un electrometre a lame vibrante - concu par K. E. Wilzbach et P. Riesz et perfectionne par H. Dutton, L. Mason et L. Blair. Grace a l'emploi de ''Teflon'' et de caoutchouc de silicones pour les elements isolants de la chambre d'ionisation, cet ensemble peut fonctionner a des temperatures voisines de 300{sup o}C. Avec le tritium, la radiochromatographi e en colonne donne des resultats mediocres, si le liquide sortant de la colonne se repand en une couche mince et passe lentement sous un compteur a balayage continu sans fenetre ou un compteur a scintillations, alors que le meme procede a donne d'excellente resultats avec le carbone-14. Aussi est-il probable que l'on adoptera la spectrometrie a scintillations en phase liquide. Elle comporte essentiellement deux procedes differents, que les

Analyse par ToF-SIMS de matériaux organiques pour les applications en électronique organique

OpenAIRE

Terlier , Tanguy

2015-01-01

During the last decade, organic electronics have developed rapidly. However, the production of organic electronic devices is still impeded because of various technological barriers. Such systems have specific analytical needs and time-of-flight secondary ion mass spectrometry (ToF-SIMS) is per se highly relevant, particularly when considering the use of a new type of ion source based on argon clusters (Arn +). The main objective of this work was therefore to understand the ion-matter interact...

Dynamic Filament Formation by a Divergent Bacterial Actin-Like ParM Protein.

Directory of Open Access Journals (Sweden)

Anthony J Brzoska

Full Text Available Actin-like proteins (Alps are a diverse family of proteins whose genes are abundant in the chromosomes and mobile genetic elements of many bacteria. The low-copy-number staphylococcal multiresistance plasmid pSK41 encodes ParM, an Alp involved in efficient plasmid partitioning. pSK41 ParM has previously been shown to form filaments in vitro that are structurally dissimilar to those formed by other bacterial Alps. The mechanistic implications of these differences are not known. In order to gain insights into the properties and behavior of the pSK41 ParM Alp in vivo, we reconstituted the parMRC system in the ectopic rod-shaped host, E. coli, which is larger and more genetically amenable than the native host, Staphylococcus aureus. Fluorescence microscopy showed a functional fusion protein, ParM-YFP, formed straight filaments in vivo when expressed in isolation. Strikingly, however, in the presence of ParR and parC, ParM-YFP adopted a dramatically different structure, instead forming axial curved filaments. Time-lapse imaging and selective photobleaching experiments revealed that, in the presence of all components of the parMRC system, ParM-YFP filaments were dynamic in nature. Finally, molecular dissection of the parMRC operon revealed that all components of the system are essential for the generation of dynamic filaments.

Mass spectrometer introduction line: application to the analysis of impurities in uranium hexafluoride; Ligne d'introduction pour spectrometre de masse: application a l'analyse des impuretes contenues dans l'UF{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Besson, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement de physico-chimie, service des isotopes stables, section de spectrometrie de masse

1967-01-01

The continuous mass-spectrometric analysis of impurities in UF{sub 6} is possible industrially if certain conditions imposed by the nature of the gas are respected. The gas introduction line arriving at the spectrometer's source makes it possible to fix the flow-rate, to control the inlet pressure and to selectively destroy the gas containing the impurities. The operational conditions for the line are defined and a description is given of the theoretical and experimental study of the various elements of which it is composed, i.e. the leak valve, the flow-meter, the chemical trap and the servo-mechanism making it possible to regulate and control the gas flow. The dynamic characteristics of the line's various components and the performance of the equipment in the case of the analyses considered are given. (author) [French] L'analyse en continu par spectrometrie de masse des impuretes contenus dans l'UF{sub 6} est possible industriellement moyennant certaines conditions imposees par la nature du gaz. La ligne d'introduction des gaz dans la source du spectrometre permet de regler le debit, de controler la pression d'introduction et de detruire selectivement le gaz porteur d'impuretes. Les conditions de fonctionnement de la ligne etant definies, on decrit l'etude theorique et experimentale des differents elements qui la composent, c'est-a-dire: le robinet a fuite, le debitmetre, le piege chimique et l'ensemble d'asservissement permettant la regulation et le controle du debit. On donne les caracteristiques dynamiques des differents constituants de la ligne et les performances de l'ensemble pour les analyses considerees. (auteur)

Estimation of the fraction of absorbed photosynthetically active radiation (fPAR) in maize canopies using LiDAR data and hyperspectral imagery.

Science.gov (United States)

Qin, Haiming; Wang, Cheng; Zhao, Kaiguang; Xi, Xiaohuan

2018-01-01

Accurate estimation of the fraction of absorbed photosynthetically active radiation (fPAR) for maize canopies are important for maize growth monitoring and yield estimation. The goal of this study is to explore the potential of using airborne LiDAR and hyperspectral data to better estimate maize fPAR. This study focuses on estimating maize fPAR from (1) height and coverage metrics derived from airborne LiDAR point cloud data; (2) vegetation indices derived from hyperspectral imagery; and (3) a combination of these metrics. Pearson correlation analyses were conducted to evaluate the relationships among LiDAR metrics, hyperspectral metrics, and field-measured fPAR values. Then, multiple linear regression (MLR) models were developed using these metrics. Results showed that (1) LiDAR height and coverage metrics provided good explanatory power (i.e., R2 = 0.81); (2) hyperspectral vegetation indices provided moderate interpretability (i.e., R2 = 0.50); and (3) the combination of LiDAR metrics and hyperspectral metrics improved the LiDAR model (i.e., R2 = 0.88). These results indicate that LiDAR model seems to offer a reliable method for estimating maize fPAR at a high spatial resolution and it can be used for farmland management. Combining LiDAR and hyperspectral metrics led to better performance of maize fPAR estimation than LiDAR or hyperspectral metrics alone, which means that maize fPAR retrieval can benefit from the complementary nature of LiDAR-detected canopy structure characteristics and hyperspectral-captured vegetation spectral information.

First (18)F-labeled ligand for PET imaging of uPAR

DEFF Research Database (Denmark)

Persson, Morten; Liu, Hongguang; Madsen, Jacob

2013-01-01

Urokinase-type plasminogen activator receptor (uPAR) is overexpressed in human prostate cancer and uPAR has been found to be associated with metastatic disease and poor prognosis. AE105 is a small linear peptide with high binding affinity to uPAR. We synthesized an N-terminal NOTA......-conjugated version (NOTA-AE105) for development of the first (18)F-labeled uPAR positron-emission-tomography PET ligand using the Al(18)F radiolabeling method. In this study, the potential of (18)F-AlF-NOTA-AE105 to specifically target uPAR-positive prostate tumors was investigated....

Elastic and inelastic scattering of 2 to 10 MeV protons by lithium isotopes; Diffusion elastique et inelastique des protons de 2 a 10 MeV par les isotopes du lithium

Energy Technology Data Exchange (ETDEWEB)

Laurat, M [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1969-07-01

A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten {mu}g/cm{sup 2}) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of {sup 8}Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [French] Nous decrivons le dispositif experimental mis au point pour effectuer les mesures de spectrometrie et de section efficace absolue pour les reactions induites par des protons acceleres par un Van de Graaff Tandem 12 MeV. Les particules sont detectees par des jonctions au silicium, le poids des cibles (de l'ordre d'une dizaine de {mu}g/cm{sup 2}), mesure par la methode du quartz. L'ensemble de l'appareillage a ete controle par l'etude de la diffusion des protons par le lithium 6, et nous a permis de preciser les diffusions elastiques et inelastiques (excitation du 1er niveau) des protons de 2 a 9 MeV par le lithium 7. La structure observee a permis de determiner les spin et parite les plus probables de six niveaux du {sup 8}Be entre 19 et 25 MeV d'energie d'excitation. (auteur)

Elastic and inelastic scattering of 2 to 10 MeV protons by lithium isotopes; Diffusion elastique et inelastique des protons de 2 a 10 MeV par les isotopes du lithium

Energy Technology Data Exchange (ETDEWEB)

Laurat, M. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1969-07-01

A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten {mu}g/cm{sup 2}) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of {sup 8}Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [French] Nous decrivons le dispositif experimental mis au point pour effectuer les mesures de spectrometrie et de section efficace absolue pour les reactions induites par des protons acceleres par un Van de Graaff Tandem 12 MeV. Les particules sont detectees par des jonctions au silicium, le poids des cibles (de l'ordre d'une dizaine de {mu}g/cm{sup 2}), mesure par la methode du quartz. L'ensemble de l'appareillage a ete controle par l'etude de la diffusion des protons par le lithium 6, et nous a permis de preciser les diffusions elastiques et inelastiques (excitation du 1er niveau) des protons de 2 a 9 MeV par le lithium 7. La structure observee a permis de determiner les spin et parite les plus probables de six niveaux du {sup 8}Be entre 19 et 25 MeV d'energie d'excitation. (auteur)

Narrative Identities and the Plebiscite in Pará: An Analysis of the Front Pages for O Liberal and Diário do Pará

Directory of Open Access Journals (Sweden)

Alda Cristina Silva da Costa

2017-05-01

Full Text Available On December 11, 2011, a plebiscite was held in Pará proposing to create two separatist states, Carajás and Tapajós, out of the state of Pará. The public voted against both projects. This article analyzes the narrative identities found on the front pages of O Liberal and Diário do Pará newspapers about the plebiscite in Pará. Depth Hermeneutics (DH, as proposed by Thompson (2011, was used as the methodological reference. DH emphasizes the object of analysis as a meaningful symbolic construction requiring interpretation. Narrative analysis, as proposed by Motta (2007, was the main research technique used to highlight the movement of construction of journalistic (discursive characters. The narrative identities built by the two newspapers showed that both were against the creation of the new states, but for very different reasons. The flag of Pará was the main object used to induce the idea of unity. Em 11 de dezembro de 2011, o plebiscito no Pará propôs a criação dos estados de Carajás e de Tapajós a partir da divisão do estado do Pará. O resultado da consulta pública foi negativo aos dois projetos. O artigo analisa as identidades narrativas constituídas pelas primeiras páginas dos jornais O Liberal e Diário do Pará sobre o plebiscito no Pará. Utilizou-se como referencial metodológico a Hermenêutica em Profundidade (HP, proposta por Thompson (2011. A HP evidencia o fato de que o objeto de análise é uma construção simbólica significativa, que exige uma interpretação. Como principal técnica de pesquisa, a análise narrativa, proposta por Motta (2007, com ênfase no movimento de construção de personagens jornalísticas (discursivas. As identidades narrativas construídas pelos dois jornais indicaram que ambos eram contrários à criação dos novos estados, porém por motivos divergentes. A bandeira do Pará foi o principal elemento utilizado para evocar a ideia de unidade. En 11 de diciembre de 2011, el plebiscito en

Limnological database for Par Pond: 1959 to 1980

International Nuclear Information System (INIS)

Tilly, L.J.

1981-03-01

A limnological database for Par Pond, a cooling reservoir for hot reactor effluent water at the Savannah River Plant, is described. The data are derived from a combination of research and monitoring efforts on Par Pond since 1959. The approximately 24,000-byte database provides water quality, primary productivity, and flow data from a number of different stations, depths, and times during the 22-year history of the Par Pond impoundment. The data have been organized to permit an interpretation of the effects of twenty years of cooling system operations on the structure and function of an aquatic ecosystem

Soluble urokinase plasminogen activator receptor (suPAR) in acute care

DEFF Research Database (Denmark)

Rasmussen, Line Jee Hartmann; Ladelund, Steen; Haupt, Thomas Huneck

2016-01-01

for age, sex, Charlson score and C reactive protein. Area under the curve for receiver operating characteristics curve analysis of suPAR for 30-day mortality was 0.84 (95% CI 0.81 to 0.86). Furthermore, in the entire cohort, women had slightly higher suPAR compared with men, and suPAR was associated...

Applications of mass spectrometry in the trace element analysis of biological materials

International Nuclear Information System (INIS)

Moens, L.

1997-01-01

The importance of mass spectrometry for the analysis of biological material is illustrated by reviewing the different mass spectrometric methods applied and describing some typical applications published recently. Though atomic absorption spectrometry is used in the majority of analyses of biological material, most mass spectrometric methods have been used to some extent for trace element determination in biomedical research. The relative importance of the different methods is estimated by reviewing recent research papers. It is striking that especially inductively coupled plasma mass spectrometry is increasingly being applied, partly because the method can be used on-line after chromatographic separation, in speciation studies. Mass spectrometric methods prove to offer unique possibilities in stable isotope tracer studies and for this purpose also experimentally demanding methods such as thermal ionization mass spectrometry and accelerator mass spectrometry are frequently used. (orig.)

Measurement of the quantity of water in organic solvents by infrared absorption an measurement of the dielectric constants; Dosage de l'eau dans les solvants organiques par absorption infra-rouge et mesure des constantes dielectriques

Energy Technology Data Exchange (ETDEWEB)

Desnoyer, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1959-06-15

Some chemical methods for the analysis of the quantity of water in solvents are first described, their object being the determination of the maximum error for cases where the water content is less than 1 per cent. - The first part of the work consists in describing infrared spectrometry as applied to the analysis of water in carbon tetrachloride, chloroform aniline, acetone and dioxane. A method based on isotopic exchange between heavy and light water is used on the one hand for determining the solubility of water in carbon tetrachloride and on the other hand for establishing standard solutions (sensitivity of the method). - In the second part the dielectric constant of water solvent solutions is measured. A table is presented giving the precision obtained by the two principal methods. These are comparable and further than that the appearance of the spectra suggests an interpretation of the anomalies observed in calibration curves obtained by the dielectric constant method. (author) [French] Quelques methodes chimiques d'analyses de l'eau dissoute dans les solvants sont decrites tout d'abord en vue de determiner l'erreur maxima dans le cas ou la teneur en eau ne depasse pas 1 pour cent. - Une premiere partie du travail expose la technique utilisee en spectrometrie infrarouge pour doser l'eau dans le tetrachlorure de carbone, chloroforme, aniline, acetone et le dioxane. Une methode basee sur l'echange isotopique entre l'eau legere et l'eau lourde permet de determiner d'une part la solubilite de l'eau dans le tetrachlorure de carbone et le chloroforme et d'autre part le titre en valeur absolue des solutions etalons (sensibilite de la methode). - Dans une deuxieme partie, on mesure la constante dielectrique des solutions eau-solvant. On dresse un tableau des precisions obtenues par les deux methodes principales. Celles-ci sont comparables et en outre, l'aspect du spectre suggere une interpretation des anomalies observees dans les courbes d'etalonnage tracees par la

Ionizing radiation effects in Acai oil analysed by gas chromatography coupled to mass spectrometry technique

International Nuclear Information System (INIS)

Valli, Felipe; Fernandes, Carlos Eduardo; Moura, Sergio; Machado, Ana Carolina; Furasawa, Helio Akira; Pires, Maria Aparecida Faustino; Bustillos, Oscar Vega

2007-01-01

The Acai fruit is a well know Brazilian seed plant used in large scale as a source of feed stock, specially in the Brazilian North-east region. The Acai oil is use in many purposes from fuel sources to medicine. The scope of this paper is to analyzed the chemical structures modification of the acai oil after the ionizing radiation. The radiation were set in the range of 10 to 25 kGy in the extracted Acai oil. The analyses were made by gas chromatography coupled to mass spectrometry techniques. A GC/MS Shimatzu QP-5000 equipped with 30 meters DB-5 capillary column with internal diameter of 0.25 mm and 0.25 μm film thickness was used. Helium was used as carried gas and gave a column head pressure of 12 p.s.i. (1 p.s.i. = 6894.76 Pa) and an average flux of 1 ml/min. The temperature program for the GC column consisted of a 4-minutes hold at 75 deg C, a 15 deg C /min ramp to 200 deg C, 8 minutes isothermal. 20 deg C/min ramp to 250 deg C, 2 minutes isothermal. The extraction of the fatty acids was based on liquid-liquid method using chloroform as solvent. The chromatograms resulted shows the presences of the oleic acid and others fatty acids identify by the mass spectra library (NIST-92). The ionization radiation deplete the fatty acids presents in the Acai oil. Details on the chemical qualitative analytical is present as well in this work. (author)

Online Ozonolysis Combined with Ion Mobility-Mass Spectrometry Provides a New Platform for Lipid Isomer Analyses

Energy Technology Data Exchange (ETDEWEB)

Poad, Berwyck L.; Zheng, Xueyun; Mitchell, Todd A.; Smith, Richard D.; Baker, Erin M.; Blanksby, Stephen J.

2017-12-21

One of the most significant challenges in contemporary lipidomics lies in the separation and identification of lipid isomers that differ only in site(s) of unsaturation or geometric configuration of the carbon-carbon double bonds. While analytical separation techniques including ion mobility spectrometry (IMS) and liquid chromatography (LC) can separate isomeric lipids under appropriate conditions, conventional tandem mass spectrometry cannot provide unequivocal identification. To address this challenge, we have implemented ozone-induced dissociation (OzID) in-line with LC, IMS and high resolution mass spectrometry. Modification of an IMS- capable quadrupole time-of-flight mass spectrometer was undertaken to allow the introduction of ozone into the high-pressure trapping ion funnel region preceding the IMS cell. This enabled the novel LC-OzID-IMS-MS configuration where ozonolysis of ionized lipids occurred rapidly (10 ms) without prior mass-selection. LC-elution time alignment combined with accurate mass and arrival time extraction of ozonolysis products facilitated correlation of precursor and product ions without mass-selection (and associated reductions in duty cycle). Unsaturated lipids across 11 classes were examined using this workflow in both positive and negative ion modalities and in all cases the positions of carbon-carbon double bonds were unequivocally assigned based on predictable OzID transitions. Under these conditions geometric isomers exhibited different IMS arrival time distributions and distinct OzID product ion ratios providing a means for discrimination of cis/trans double bonds in complex lipids. The combination of OzID with multidimensional separations shows significant promise for facile profiling of unsaturation patterns within complex lipidomes.

Intact and cleaved uPAR forms: diagnostic and prognostic value in cancer

DEFF Research Database (Denmark)

Rasch, M.G.; Lund, I.K.; Hoyer-Hansen, G.

2008-01-01

identified in tissue and body fluids. It is well-established, that the total amount of all uPAR forms is a strong prognostic marker in different types of cancer. Using immunoassays, measuring the individual uPAR forms, has revealed that the cleaved uPAR forms are even stronger prognostic markers and have...... diagnostic utility. This review will focus on the mechanism of uPAR cleavage and the functional consequences, as well as the clinical applicability of cleaved uPAR forms Udgivelsesdato: 2008...

Overtone Mobility Spectrometry: Part 4. OMS-OMS Analyses of Complex Mixtures

Science.gov (United States)

Kurulugama, Ruwan T.; Nachtigall, Fabiane M.; Valentine, Stephen J.; Clemmer, David E.

2011-11-01

A new, two-dimensional overtone mobility spectrometry (OMS-OMS) instrument is described for the analysis of complex peptide mixtures. OMS separations are based on the differences in mobilities of ions in the gas phase. The method utilizes multiple drift regions with modulated drift fields such that only ions with appropriate mobilities are transmitted to the detector. Here we describe a hybrid OMS-OMS combination that utilizes two independently operated OMS regions that are separated by an ion activation region. Mobility-selected ions from the first OMS region are exposed to energizing collisions and may undergo structural transitions before entering the second OMS region. This method generates additional peak capacity and allows for higher selectivity compared with the one-dimensional OMS method. We demonstrate the approach using a three-protein tryptic digest spiked with the peptide Substance P. The [M + 3H]3+ ion from Substance P can be completely isolated from other components in this complex mixture prior to introduction into the mass spectrometer.

A Bipolar Spindle of Antiparallel ParM Filaments Drives Bacterial Plasmid Segregation

DEFF Research Database (Denmark)

Gayathri, P; Fujii, T; Møller-Jensen, Jakob

2012-01-01

the spindle between ParRC complexes on sister plasmids. Using a combination of structural work and total internal reflection fluorescence microscopy, we show that ParRC bound and could accelerate growth at only one end of polar ParM filaments, mechanistically resembling eukaryotic formins. The architecture...... of ParM filaments enabled two ParRC-bound filaments to associate in an antiparallel orientation, forming a bipolar spindle. The spindle elongated as a bundle of at least two antiparallel filaments, thereby pushing two plasmid clusters toward the poles....

Analyse diallele du rendement graines par hectare et du poids de ...

African Journals Online (AJOL)

L'analyse de variance associée aux aptitudes générales et spécifiques à la combinaison (AGC, ASC) et aux effets réciproques (ERC) montre que des effets génétiques de type additif sont à l'origine de la variabilité génétique totale pour les caractères étudiés. Ce travail a permis l'étude de l'hérédité quantitative des deux ...

PAR-2 expression in the gingival crevicular fluid reflects chronic periodontitis severity

Directory of Open Access Journals (Sweden)

Henrique FUKUSHIMA

Full Text Available Abstract Recent studies investigating protease-activated receptor type 2 (PAR-2 suggest an association between the receptor and periodontal inflammation. It is known that gingipain, a bacterial protease secreted by the important periodontopathogen Porphyromonas gingivalis can activate PAR-2. Previous studies by our group found that PAR-2 is overexpressed in the gingival crevicular fluid (GCF of patients with moderate chronic periodontitis (MP. The present study aimed at evaluating whether PAR-2 expression is associated with chronic periodontitis severity. GCF samples and clinical parameters, including plaque and bleeding on probing indices, probing pocket depth and clinical attachment level, were collected from the control group (n = 19 at baseline, and from MP patients (n = 19 and severe chronic periodontitis (SP (n = 19 patients before and 6 weeks after periodontal non-surgical treatment. PAR-2 and gingipain messenger RNA (mRNA in the GCF of 4 periodontal sites per patient were evaluated by Reverse Transcription Polymerase Chain Reaction (RT-qPCR. PAR-2 and gingipain expressions were greater in periodontitis patients than in control group patients. In addition, the SP group presented increased PAR-2 and gingipain mRNA levels, compared with the MP group. Furthermore, periodontal treatment significantly reduced (p <0.05 PAR-2 expression in patients with periodontitis. In conclusion, PAR-2 is associated with chronic periodontitis severity and with gingipain levels in the periodontal pocket, thus suggesting that PAR-2 expression in the GCF reflects the severity of destruction during periodontal infection.

Structures of actin-like ParM filaments show architecture of plasmid-segregating spindles.

Science.gov (United States)

Bharat, Tanmay A M; Murshudov, Garib N; Sachse, Carsten; Löwe, Jan

2015-07-02

Active segregation of Escherichia coli low-copy-number plasmid R1 involves formation of a bipolar spindle made of left-handed double-helical actin-like ParM filaments. ParR links the filaments with centromeric parC plasmid DNA, while facilitating the addition of subunits to ParM filaments. Growing ParMRC spindles push sister plasmids to the cell poles. Here, using modern electron cryomicroscopy methods, we investigate the structures and arrangements of ParM filaments in vitro and in cells, revealing at near-atomic resolution how subunits and filaments come together to produce the simplest known mitotic machinery. To understand the mechanism of dynamic instability, we determine structures of ParM filaments in different nucleotide states. The structure of filaments bound to the ATP analogue AMPPNP is determined at 4.3 Å resolution and refined. The ParM filament structure shows strong longitudinal interfaces and weaker lateral interactions. Also using electron cryomicroscopy, we reconstruct ParM doublets forming antiparallel spindles. Finally, with whole-cell electron cryotomography, we show that doublets are abundant in bacterial cells containing low-copy-number plasmids with the ParMRC locus, leading to an asynchronous model of R1 plasmid segregation.

CALiPER Report 20.5: Chromaticity Shift Modes of LED PAR38 Lamps Operated in Steady-State Conditions

Energy Technology Data Exchange (ETDEWEB)

Davis, J. Lynn [RTI International, Research Triangle Park, NC (United States); Young, Joseph [RTI International, Research Triangle Park, NC (United States); Royer, Michael [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-02-26

This report builds on CALiPER Report 20.4, focusing on the same 32 PAR38 lamps but investigating causes of color shift and parametric failures. It provides a tear-down analysis of the lamp models and performs additional analyses on the spectroradiometric data obtained using a specially developed automated long-term test apparatus.

Study of the coefficient of separation for some processes which are applied to lithium isotopes; Etude du coefficient de separation de quelques processus concernant les isotopes du lithium

Energy Technology Data Exchange (ETDEWEB)

Perret, L; Rozand, L; Saito, E [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

The fundamental separation factors of some processes are investigated: the distillation of metallic lithium, counter current electromigration in fused salts (particularly in lithium nitrate) electrolysis in aqueous solution and ion exchange. The chemical transfer between a lithium amalgam and lithium salts in a dimethylformamide solution (a solvent which is not attacked by the amalgam) is also studied. Finally a description is given of isotopic analyses carried out either by scintillation counting or by mass spectrography using apparatus specially designed for this particular task. (author) [French] Les facteurs de separation elementaires de quelques processus connus sont etudies: distillation du lithium metallique, electromigration a contre-courant en sels fondus (en particulier le nitrate), electrolyse en solution aqueuse et echange d'ions. L'echange chimique entre l'amalgame de lithium et les sels de lithium en solution dans la dimethylformamide - solvant non attaque par l'amalgame - est egalement etudie. Enfin, on decrit les methodes d 'analyse isotopique, soit par comptage par scintillation, soit par spectrometrie de masse au moyen d'un appareil specialement concu pour cet usage particulier. (auteur)

Study of the coefficient of separation for some processes which are applied to lithium isotopes; Etude du coefficient de separation de quelques processus concernant les isotopes du lithium

Energy Technology Data Exchange (ETDEWEB)

Perret, L.; Rozand, L.; Saito, E. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

The fundamental separation factors of some processes are investigated: the distillation of metallic lithium, counter current electromigration in fused salts (particularly in lithium nitrate) electrolysis in aqueous solution and ion exchange. The chemical transfer between a lithium amalgam and lithium salts in a dimethylformamide solution (a solvent which is not attacked by the amalgam) is also studied. Finally a description is given of isotopic analyses carried out either by scintillation counting or by mass spectrography using apparatus specially designed for this particular task. (author) [French] Les facteurs de separation elementaires de quelques processus connus sont etudies: distillation du lithium metallique, electromigration a contre-courant en sels fondus (en particulier le nitrate), electrolyse en solution aqueuse et echange d'ions. L'echange chimique entre l'amalgame de lithium et les sels de lithium en solution dans la dimethylformamide - solvant non attaque par l'amalgame - est egalement etudie. Enfin, on decrit les methodes d 'analyse isotopique, soit par comptage par scintillation, soit par spectrometrie de masse au moyen d'un appareil specialement concu pour cet usage particulier. (auteur)

Focusing procedures in time-of-flight mass spectrometry

International Nuclear Information System (INIS)

Ioanoviciu, D.

2002-01-01

Time-of-flight mass spectrometry is a fast growing field due to its ability to handle very fast processes and due to its theoretically unlimited mass range. The performances of the time-of-flight mass analysers are heavily dependent on the progress in ion optics, a periodically reviewed field. In this presentation the various focusing procedures in time-of-flight mass spectrometry are reviewed. For ions of the same charge and mass flight time differences result from different potentials at the location of formation and from the initial velocity spread. There is no simultaneous space and velocity focusing in time-of-flight mass spectrometry. Space focusing of first and second order can be reached in time-of-flight mass analysers having two homogeneous electric field ion sources followed by a field free space in front of the detector. Single and double stage homogeneous electric field mirrors can focus in time ions of different energies. These different energies result when ions leaving different initial sites and arriving simultaneously to an intermediate space focus. Convenient mass dispersion can be obtained by including a mirror. Initial velocity focusing is obtained by the delayed extraction procedure in drift space and mirror time-of-flight mass analysers. Post source pulse focusing aims at the same purpose. Ion source electrodes of hyperbolic shape, operated by high voltage pulses can bring major improvements of the resolution, especially at high masses. For each focusing procedure the geometric and/or electric conditions are given as well as the aberrations allowing the mass resolution determination. The various focusing procedures are compared and a prediction of their future performances was tempted. (author)

Rabies in humans and non-human in the state of Pará, Brazilian Amazon

Directory of Open Access Journals (Sweden)

Marcus Emanuel Barroncas Fernandes

2013-04-01

Full Text Available We evaluate the relationship of positive cases of rabies with the continuing expansion of livestock production, and analyse the trends of this zoonosis in human population in the state of Pará, Brazilian Amazon. The distribution of rabies cases was recorded between 1999 and 2004. Of 148 cases of rabies, 21% were in humans and 79% in non-human mammals. The rapid growth in livestock numbers seems to be associated with the increase of positive cases in bovine livestock transmitted by vampire bats. This idea is supported by positive and significant relationship of both events in time (p < 0.01, but failed when spatial distribution among regions of the state was considered. However, rabies cases tend to occur toward the northeastern of the state of Pará, where rabies cases are proportionally five times greater than other mesoregions, suggesting that increased livestock production may influence the increase of this zoonosis.

Rabies in humans and non-human in the state of Pará, Brazilian Amazon

Directory of Open Access Journals (Sweden)

Marcus Emanuel Barroncas Fernandes

Full Text Available We evaluate the relationship of positive cases of rabies with the continuing expansion of livestock production, and analyse the trends of this zoonosis in human population in the state of Pará, Brazilian Amazon. The distribution of rabies cases was recorded between 1999 and 2004. Of 148 cases of rabies, 21% were in humans and 79% in non-human mammals. The rapid growth in livestock numbers seems to be associated with the increase of positive cases in bovine livestock transmitted by vampire bats. This idea is supported by positive and significant relationship of both events in time (p < 0.01, but failed when spatial distribution among regions of the state was considered. However, rabies cases tend to occur toward the northeastern of the state of Pará, where rabies cases are proportionally five times greater than other mesoregions, suggesting that increased livestock production may influence the increase of this zoonosis.

Par and IR reflectance, transmittance, and absorptance of four crop canopies

International Nuclear Information System (INIS)

Wanjura, D.F.; Hatfield, J.L.

1986-01-01

Reflectance, transmittance and absorptance of electromagnetic radiation by cotton, soybeans, grain sorghum, and sunflower was measured at three growth stages in two wavebands (PAR: 0.4 to 0.7 pun and IR: 0.7 to 1.1 yim). As leaf area increased in each crop there were increases in IR reflectance and PAR absorptance and decreases in PAR reflectance and both PAR and IR transmittance. IR radiation was concentrated at the soil surface between rows by reflectance from the sides of canopies when crop cover was less than 80%. Across all crops one parameter, leaf overlap index, explained 81 and 71% of the PAR reflectance and another, crop cover, explained 86 and 94% of IR reflectance from rows and interrows, respectively. Attenuation of PAR radiation through the canopies of cotton and sunflower was similar (K = 0.62 and 0.67) but different from that of soybeans and grain sorghum (K = 0.46 and 0.43) which were the same

Épidémiologie de l'intoxication par envenimation chez les enfants ...

African Journals Online (AJOL)

Introduction: L'intoxication par envenimation est l'ensemble des manifestations locales et générales induites par la pénétration dans l'organisme d'une substance toxique produite par un animal venimeux. Le but de notre travail était d'étudier les signes cliniques des intoxications par envenimation chez les enfants de 0 à 15 ...

Multielement trace analyses of SINQ materials by ICP-OES

Energy Technology Data Exchange (ETDEWEB)

Keil, R.; Schwikowski, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1997-09-01

Inductively Coupled Plasma Optical Emission Spectrometry was used to analyse 70 elements in various materials used for construction of the SINQ. Detection limits for individual elements depend strongly on the matrix and had to be determined separately. (author) 1 tab.

PARs for combustible gas control in advanced light water reactors

International Nuclear Information System (INIS)

Hosler, J.; Sliter, G.

1997-01-01

This paper discusses the progress being made in the United States to introduce passive autocatalytic recombiner (PAR) technology as a cost-effective alternative to electric recombiners for controlling combustible gas produced in postulated accidents in both future Advanced Light Water Reactors (ALWRs) and certain U. S. operating nuclear plants. PARs catalytically recombine hydrogen and oxygen, gradually producing heat and water vapor. They have no moving parts and are self-starting and self-feeding, even under relatively cold and wet containment conditions. Buoyancy of the hot gases they create sets up natural convective flow that promotes mixing of combustible gases in a containment. In a non-inerted ALWR containment, two approaches each employing a combination of PARs and igniters are being considered to control hydrogen in design basis and severe accidents. In pre-inerted ALWRs, PARs alone control radiolytic oxygen produced in either accident type. The paper also discusses regulatory feedback regarding these combustible gas control approaches and describes a test program being conducted by the Electric Power Research Institute (EPRI) and Electricite de France (EdF) to supplement the existing PAR test database with performance data under conditions of interest to U.S. plants. Preliminary findings from the EPRI/EdF PAR model test program are included. Successful completion of this test program and confirmatory tests being sponsored by the U. S. NRC are expected to pave the way for use of PARs in ALWRs and operating plants. (author)

Brulure par Plaque de Bistouri Electrique: a Propos de Quatre Cas

Science.gov (United States)

Khales, A.; Achbouk, A.; Belmir, R.; Cherkab, L.; Ennouhi, M.A.; Ababou, K.; Ihrai, H.

2010-01-01

Summary La brûlure par plaque de bistouri électrique est un accident rare mais grave par la profondeur de la lésion et par sa localisation, surtout quand qu’elle survient dans un contexte chirurgical dont le vécu reste difficile de la part du malade et du chirurgien. Cette brûlure bien que imprévisible reste grave par la profondeur et la localisation de la brûlure et par sa survenue dans un contexte opératoire, chez des patients malades. La prise en charge de la brûlure doit se faire en milieu spécialisé. La prévention reste le seul moyen d’éviter ce type d’accident. PMID:21991216

Co-combustion characteristics and blending optimization of tobacco stem and high-sulfur bituminous coal based on thermogravimetric and mass spectrometry analyses.

Science.gov (United States)

Zhang, Kaihua; Zhang, Kai; Cao, Yan; Pan, Wei-ping

2013-03-01

Despite much research on co-combustion of tobacco stem and high-sulfur coal, their blending optimization has not been effectively found. This study investigated the combustion profiles of tobacco stem, high-sulfur bituminous coal and their blends by thermogravimetric analysis. Ignition and burnout performances, heat release performances, and gaseous pollutant emissions were also studied by thermogravimetric and mass spectrometry analyses. The results indicated that combustion of tobacco stem was more complicated than that of high-sulfur bituminous coal, mainly shown as fixed carbon in it was divided into two portions with one early burning and the other delay burning. Ignition and burnout performances, heat release performances, and gaseous pollutant emissions of the blends present variable trends with the increase of tobacco stem content. Taking into account the above three factors, a blending ratio of 0–20% tobacco stem content is conservatively proposed as optimum amount for blending. Copyright © 2012 Elsevier Ltd. All rights reserved.

Elusloom lennukiga puhkusele / Inge Parring

Index Scriptorium Estoniae

Parring, Inge

2003-01-01

Ilmunud ka: Delovõje Vedomosti 1. okt. lk. 13. Air Cargo Estonia/ACE Logisticsi müügijuht Inge Parring tutvustab elusloomade transpordivõimalusi. Vt. samas: Loomade transportimiseks vajalikud dokumendid

suPAR

DEFF Research Database (Denmark)

Eugen-Olsen, Jesper; Giamarellos-Bourboulis, Evangelos J

2015-01-01

Investigation of biomarkers that can promptly predict unfavourable outcome of critically illness is an emerging necessity taking into consideration the need for early intervention, the shortage of available beds in intensive care units and the considerable cost of hospitalisation. The most...... promising biomarker is soluble urokinase-type plasminogen activator receptor (suPAR). Three studies in large populations of critically ill patients and patients admitted to the emergency department have shown that concentrations >12ng/mL can safely predict unfavourable outcome. This review presents...

Urine suPAR levels compared with plasma suPAR levels as predictors of post-consultation mortality risk among individuals assumed to be TB-negative: a prospective cohort study

DEFF Research Database (Denmark)

Rabna, Paulo; Andersen, Andreas; Wejse, Christian

2010-01-01

-suPAR was measured using a commercial ELISA (suPARnostic®). We found that U-suPAR carried significant prognostic information on mortality for HIV-infected subjects with an area under the ROC curve of 0.75. For HIV-negative individuals, little or no prognostic effect was observed. However, in both HIV positives...... and negatives, the predictive effect of U-suPAR was found to be inferior to that of P-suPAR....

Brésil : La contamination par le mercure en Amazonie | CRDI ...

International Development Research Centre (IDRC) Digital Library (Canada)

11 janv. 2011 ... En tentant de déceler la source de la contamination de l'Amazone par le ... par Jean-Rémy Davy Guimaraes de l'Université fédérale de Rio de Janeiro ... ces mattes est circonscrite par la conservation et la restauration en rive.

Raman spectra of ordinary and deuterated liquid ammonias; Spectres Raman des ammoniacs ordinaire et deuteries liquides

Energy Technology Data Exchange (ETDEWEB)

Ceccaldi, M; Leicknam, J P [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires, direction des materiaux et des combustibles nucleaires, departement de physico-chimie, service des isotopes stables, service de spectrometrie de masse

1968-12-01

les intensites relatives sont approximativement conformes aux previsions; au contraire, les spectres Raman presentent dans la meme region une bande supplementaire intense, dont l'apparition est due a une resonance de Fermi; par des considerations theoriques on peut expliquer pourquoi cette resonance est si facilement mise en evidence par Raman, alors qu'on ne la detecte en spectrometrie infra-rouge que par une analyse tres approfondie des effets de solvants sur l'ammoniac. (auteurs)

Un « gouvernement des journalistes par le Pouvoir politique » par défaut ?

Directory of Open Access Journals (Sweden)

Matthieu Lardeau

2013-12-01

Full Text Available Cet article présente les interactions de deux mouvements concomitants apparusprincipalement dans les décennies 1950 à 1970 dans le champ de la presse française : d’un côté les initiatives – consécutives à la démarche pionnière, en 1951, de création de la première Société des journalistes (SDJ au sein du Monde – menées par les journalistes de rédactions de quotidiens pour créer des SDJ dont la destination peut aller jusqu’à gouverner les journaux; de l’autre côté, les « réponses » apportées par les Pouvoirs politique et public pour contenir ces initiatives visant à étendre le pouvoir des journalistes dans la gestion et la gouvernance de leurs journaux. Cette étude exploratoire repose principalement sur l’analyse de deux types de littérature, souvent déconsidérés ou négligés par le champ académique, en dépit de leur grande richesse : (1 la littérature professionnelle, ayant pour principaux auteurs les journalistes et managers de presse (Périer Daville, Boegner, Pigasse, etc., florissante depuis 1944 et singulièrement durant les décennies 1960 et 1970 ; (2 la littérature grise constituée notamment par des rapports publics rédigés par des institutions comme les services du Premier ministre (commissions Lindon de 1970 et Serisé de 1972, le Conseil économique et social, etc. Nos principaux résultats montrent que les propositions ou actions menées par les journalistes (1 restent le plus souvent inexploitées in concreto par les journalistes eux-mêmes; (2 entrent le plus souvent en opposition avec les politiques de nouveaux actionnaires ou directions de journaux et avec les projets des autorités politiques et publiques qui cherchent à encadrer l’autonomie de la profession journalistique pour mieux gouverner celle-ci ; (3 combien in fine les représentants des différents acteurs impliqués s’accordent pour contenir l’émergence d’un « gouvernement des journalistes » par les

Analyse situationnelle de la lutte antitabac au Kenya | CRDI - Centre ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le Kenya est l'un des 12 pays d'Afrique subsaharienne participant à l'initiative Analyses situationnelles de la lutte antitabac en Afrique (ASTA) financée par le CRDI et la Fondation Bill et Melinda Gates. L'objectif de cette initiative est de favoriser la compréhension des possibilités et des obstacles liés à la lutte antitabac et ...

Analyse conceptuelle et traductibilité des termes de maladie dioula

NARCIS (Netherlands)

Diaby Kassamba, Oumou Koultoum

2015-01-01

Ce livre est une étude pionnière portant sur l’analyse conceptuelle et la traductibilité des termes de maladie dioula jusqu’ici non abordées par les recherches antérieures. Le Dioula est une langue mandé parlée au Burkina Faso. L’étude présente les représentations de la santé, de la maladie et du

Electron microscope study of vacancy clusters produced by quenching in magnesium; Etude par microscopie electronique des amas de lacunes crees par trempe dans le magnesium

Energy Technology Data Exchange (ETDEWEB)

Levy, V; Espinasse, J; Mairy, C; Hillairet, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

Vacancy clustering in quenched magnesium has been studied by transmission electron microscopy. The nature of the vacancy loops observed, seems to depend essentially on the impurity content of the metal; this effect can be attributed to a variation of the stacking fault energy of magnesium due to impurities. (authors) [French] On a etudie par microscopie electronique en transmission les defauts crees par trempe dans le magnesium. Un effet considerable des impuretes du metal sur la nature des boucles obtenues par condensation de lacunes a ete mis en evidence; cet effet semble s'expliquer de facon satisfaisante par un abaissement de l'energie de faute d'empilement du magnesium du aux impuretes. (auteur)

ParABS Systems of the Four Replicons of Burkholderia cenocepacia: New Chromosome Centromeres Confer Partition Specificity†

Science.gov (United States)

Dubarry, Nelly; Pasta, Franck; Lane, David

2006-01-01

Most bacterial chromosomes carry an analogue of the parABS systems that govern plasmid partition, but their role in chromosome partition is ambiguous. parABS systems might be particularly important for orderly segregation of multipartite genomes, where their role may thus be easier to evaluate. We have characterized parABS systems in Burkholderia cenocepacia, whose genome comprises three chromosomes and one low-copy-number plasmid. A single parAB locus and a set of ParB-binding (parS) centromere sites are located near the origin of each replicon. ParA and ParB of the longest chromosome are phylogenetically similar to analogues in other multichromosome and monochromosome bacteria but are distinct from those of smaller chromosomes. The latter form subgroups that correspond to the taxa of their hosts, indicating evolution from plasmids. The parS sites on the smaller chromosomes and the plasmid are similar to the “universal” parS of the main chromosome but with a sequence specific to their replicon. In an Escherichia coli plasmid stabilization test, each parAB exhibits partition activity only with the parS of its own replicon. Hence, parABS function is based on the independent partition of individual chromosomes rather than on a single communal system or network of interacting systems. Stabilization by the smaller chromosome and plasmid systems was enhanced by mutation of parS sites and a promoter internal to their parAB operons, suggesting autoregulatory mechanisms. The small chromosome ParBs were found to silence transcription, a property relevant to autoregulation. PMID:16452432

Electron paramagnetic resonance study of radicals formed by radiolysis at 77 K of nitroalkanes and of their solutions in organic glasses. Chromatography analysis of radiolysis products of nitromethane in ethanol solution in a vitreous medium; Etude par resonance paramagnetique electronique des radicaux formes par radiolyse a 77 K des nitroalcanes et de leurs solutions dans les verres organiques analyse par chromatographie des produits de la radiolyse du nitromethane en solution dans l'ethanol en milieux vitreux

Energy Technology Data Exchange (ETDEWEB)

Rosilio, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1968-05-01

etude porte sur la structure et la reactivite des radicaux formes par irradiation 7 des derives nitres a 77 K, et sur le mecanisme de formation et de disparition de ces radicaux dans les differentes matrices utilisees. Les radicaux resultant de l'arrachement d'un hydrogene en {alpha} du groupe NO{sub 2}, et les radicaux resultant de reactions d'addition sur le groupe nitre caracterises par un electron non apparie sur l'azote ont ete identifies, soit dans la radiolyse des nitroalcanes purs, soit dans la radiolyse a 77 K des nitroalcanes en solution dans les verres organiques. La conformation et les mouvements des radicaux dans les matrices, le mecanisme de formation des radicaux observes resultant generalement de la capture par les nitroalcanes des especes primaires de la radiolyse ont ete etudies. Les nitroalcanes en solution dans l'ethanol se manifestent a la fois comme capteurs d'electrons et de radicaux libres. L'etude de la radiolyse des nitroalcanes en solution dans un verre polaire d'ethanol a ete completee par des analyses chimiques des produits finals de la radiolyse; elle nous a permis de deduire l'efficacite de capture des electrons pieges et des radicaux libres par les nitroalcanes dans l'ethanol. Pour cela nous avons dose, pour le systeme nitro-methane - ethanol les rendements radiochimiques de-l'hydrogene, de l'acetaldehyde et du glycol en fonction de la concentration en capteur. Un mecanisme de disparition des radicaux observes a ete propose. (auteur)

Electron paramagnetic resonance study of radicals formed by radiolysis at 77 K of nitroalkanes and of their solutions in organic glasses. Chromatography analysis of radiolysis products of nitromethane in ethanol solution in a vitreous medium; Etude par resonance paramagnetique electronique des radicaux formes par radiolyse a 77 K des nitroalcanes et de leurs solutions dans les verres organiques analyse par chromatographie des produits de la radiolyse du nitromethane en solution dans l'ethanol en milieux vitreux

Energy Technology Data Exchange (ETDEWEB)

Rosilio, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1968-05-01

radiolyse. Notre etude porte sur la structure et la reactivite des radicaux formes par irradiation 7 des derives nitres a 77 K, et sur le mecanisme de formation et de disparition de ces radicaux dans les differentes matrices utilisees. Les radicaux resultant de l'arrachement d'un hydrogene en {alpha} du groupe NO{sub 2}, et les radicaux resultant de reactions d'addition sur le groupe nitre caracterises par un electron non apparie sur l'azote ont ete identifies, soit dans la radiolyse des nitroalcanes purs, soit dans la radiolyse a 77 K des nitroalcanes en solution dans les verres organiques. La conformation et les mouvements des radicaux dans les matrices, le mecanisme de formation des radicaux observes resultant generalement de la capture par les nitroalcanes des especes primaires de la radiolyse ont ete etudies. Les nitroalcanes en solution dans l'ethanol se manifestent a la fois comme capteurs d'electrons et de radicaux libres. L'etude de la radiolyse des nitroalcanes en solution dans un verre polaire d'ethanol a ete completee par des analyses chimiques des produits finals de la radiolyse; elle nous a permis de deduire l'efficacite de capture des electrons pieges et des radicaux libres par les nitroalcanes dans l'ethanol. Pour cela nous avons dose, pour le systeme nitro-methane - ethanol les rendements radiochimiques de-l'hydrogene, de l'acetaldehyde et du glycol en fonction de la concentration en capteur. Un mecanisme de disparition des radicaux observes a ete propose. (auteur)

MODIS-derived daily PAR simulation from cloud-free images and its validation

Energy Technology Data Exchange (ETDEWEB)

Chen, Liangfu; Gu, Xingfa; Tian, Guoliang [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101 (China); The Center for National Spaceborne Demonstration, Beijing 100101 (China); Gao, Yanhua [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101 (China); Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101 (China); Yang, Lei [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101 (China); Jilin University, Changchun 130026 (China); Liu, Qinhuo [State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101 (China)

2008-06-15

In this paper, a MODIS-derived daily PAR (photosynthetically active radiation) simulation model from cloud-free image over land surface has been developed based on Bird and Riordan's model. In this model, the total downwelling spectral surface irradiance is divided into two parts: one is beam irradiance, and another is diffuse irradiance. The attenuation of solar beam irradiance comprises scattering by the gas mixture, absorption by ozone, the gas mixture and water vapor, and scattering and absorption by aerosols. The diffuse irradiance is scattered out of the direct beam and towards the surface. The multiple ground-air interactions have been taken into account in the diffuse irradiance model. The parameters needed in this model are atmospheric water vapor content, aerosol optical thickness and spectral albedo ranging from 400 nm to 700 nm. They are all retrieved from MODIS data. Then, the instantaneous photosynthetically available radiation (IPAR) is integrated by using a weighted sum at each of the visible MODIS wavebands. Finally, a daily PAR is derived by integration of IPAR. In order to validate the MODIS-derived PAR model, we compared the field PAR measurements in 2003 and 2004 against the simulated PAR. The measurements were made at the Qianyanzhou ecological experimental station, Chinese Ecosystem Research Network. A total of 54 days of cloud-free MODIS L1B level images were used for the PAR simulation. Our results show that the simulated PAR is consistent with field measurements, where the correlation coefficient of linear regression between calculated PAR and measured PAR is 0.93396. However, there were some uncertainties in the comparison of 1 km pixel PAR with the tower flux stand measurement. (author)

Serum tetranectin is an independent prognostic marker in colorectal cancer and weakly correlated with plasma suPAR, plasma PAI-1 and serum CEA

DEFF Research Database (Denmark)

Høgdall, Claus K; Christensen, Ib J; Stephens, Ross W

2002-01-01

PAR and CEA had a 2.43 increased risk as compared to a patient with median levels of these biochemical markers. Significant correlations were found with Dukes' stages for all the biochemical markers and between the respective biochemical markers. The findings confirm that TN is a strong prognostic factor...... activator (uPAR) and carcinoembryonic antigen (CEA). Significantly shorter survival was found for patients with TN levels below a cut-off point of 7.5 mg/l compared to patients with levels above, as illustrated by Kaplan-Meier curves. By Cox analyses, log TN, log soluble uPAR as well as log CEA were found...... to have an independent prognostic value for survival (log TN: HR = 0.47, 95% CI: 0.29-0.76); log soluble uPAR: HR = 1.65, 95% CI: 1.18-2.31; log CEA: HR = 1.I1, 95% CI: 1.03-1.20). Based on the multivariate model, a patient with a combination of low levels of TN and PAI-1 and elevated levels of soluble u...

PAR-2 expression in the gingival crevicular fluid reflects chronic periodontitis severity.

Science.gov (United States)

Fukushima, Henrique; Alves, Vanessa Tubero Euzebio; Carvalho, Verônica Franco de; Ambrósio, Lucas Macedo Batitucci; Eichler, Rosangela Aparecida Dos Santos; Carvalho, Maria Helena Catelli de; Saraiva, Luciana; Holzhausen, Marinella

2017-01-26

Recent studies investigating protease-activated receptor type 2 (PAR-2) suggest an association between the receptor and periodontal inflammation. It is known that gingipain, a bacterial protease secreted by the important periodontopathogen Porphyromonas gingivalis can activate PAR-2. Previous studies by our group found that PAR-2 is overexpressed in the gingival crevicular fluid (GCF) of patients with moderate chronic periodontitis (MP). The present study aimed at evaluating whether PAR-2 expression is associated with chronic periodontitis severity. GCF samples and clinical parameters, including plaque and bleeding on probing indices, probing pocket depth and clinical attachment level, were collected from the control group (n = 19) at baseline, and from MP patients (n = 19) and severe chronic periodontitis (SP) (n = 19) patients before and 6 weeks after periodontal non-surgical treatment. PAR-2 and gingipain messenger RNA (mRNA) in the GCF of 4 periodontal sites per patient were evaluated by Reverse Transcription Polymerase Chain Reaction (RT-qPCR). PAR-2 and gingipain expressions were greater in periodontitis patients than in control group patients. In addition, the SP group presented increased PAR-2 and gingipain mRNA levels, compared with the MP group. Furthermore, periodontal treatment significantly reduced (p periodontitis. In conclusion, PAR-2 is associated with chronic periodontitis severity and with gingipain levels in the periodontal pocket, thus suggesting that PAR-2 expression in the GCF reflects the severity of destruction during periodontal infection.

Molecular mechanism of bundle formation by the bacterial actin ParM

Energy Technology Data Exchange (ETDEWEB)

Popp, David, E-mail: dpopp@imcb.a-star.edu.sg [ERATO ' Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673 Singapore (Singapore); Narita, Akihiro [ERATO ' Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Nagoya University Graduate School of Science, Structural Biology Research Center and Division of Biological Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Iwasa, Mitsusada [ERATO ' Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Maeda, Yuichiro [ERATO ' Actin Filament Dynamics' Project, Japan Science and Technology Corporation, c/o RIKEN Harima Institute at Spring 8, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Nagoya University Graduate School of Science, Structural Biology Research Center and Division of Biological Sciences, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Robinson, Robert C. [Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, 138673 Singapore (Singapore)

2010-01-22

The actin homolog ParM plays a microtubule-like role in segregating DNA prior to bacterial cell division. Fluorescence and cryo-electron microscopy have shown that ParM forms filament bundles between separating DNA plasmids in vivo. Given the lack of ParM bundling proteins it remains unknown how ParM bundles form at the molecular level. Here we show using time-lapse TIRF microscopy, under in vitro molecular crowding conditions, that ParM-bundle formation consists of two distinct phases. At the onset of polymerization bundle thickness and shape are determined in the form of nuclei of short helically disordered filaments arranged in a liquid-like lattice. These nuclei then undergo an elongation phase whereby they rapidly increase in length. At steady state, ParM bundles fuse into one single large aggregate. This behavior had been predicted by theory but has not been observed for any other cytomotive biopolymer, including F-actin. We employed electron micrographs of ParM rafts, which are 2-D analogs of 3-D bundles, to identify the main molecular interfilament contacts within these suprastructures. The interface between filaments is similar for both parallel and anti-parallel orientations and the distribution of filament polarity is random within a bundle. We suggest that the interfilament interactions are not due to the interactions of specific residues but rather to long-range, counter ion mediated, electrostatic attractive forces. A randomly oriented bundle ensures that the assembly is rigid and that DNA may be captured with equal efficiency at both ends of the bundle via the ParR binding protein.

Gas chromatography-mass spectrometry and high-performance liquid chromatographic analyses of thermal degradation products of common plastics

NARCIS (Netherlands)

Pacakova, V.; Leclercq, P.A.

1991-01-01

The thermo-oxidation of five commonly used materials, namely low-density polyethylene, retarded polyethylene, paper with a polyethylene foil, a milk package and filled polypropylene, was studied. Capillary gas chromatography and gas chromatography-mass spectrometry were used to analyze the volatile

Analyse des images satellitales radar RSO-ERS et optique ETM+ de ...

African Journals Online (AJOL)

... l'analyse des images satellitales est un outil¸ au même titre que par exemple, la géophysique de prospection minière. Les spatio-cartes géologiques obtenues peuvent permettre de mieux planifier les travaux miniers sur le terrain. Mots-clés : images satellitales, Radar RSO-ERS, ETM+ - LANDSAT 7, prospection minière, ...

Par Pond vegetation status Summer 1995 -- October survey descriptive summary

International Nuclear Information System (INIS)

Mackey, H.E. Jr.; Riley, R.S.

1995-11-01

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the emergent shoreline aquatic plant communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level and continued with this late October survey. Communities similar to the pre-drawdown Par Pond aquatic plant communities are becoming re-established; especially, beds of maiden cane, lotus, waterlily, and watershield are now extensive and well established. Cattail occurrence continues to increase, but large beds common to Par Pond prior to the drawdown have not formed. Future surveys throughout 1996 and 1997, along with the continued evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned

Par Pond vegetation status Summer 1995 -- September survey descriptive summary

International Nuclear Information System (INIS)

Mackey, H.E. Jr.; Riley, R.S.

1995-09-01

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the emergent shoreline aquatic plant communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level and continued with this mid-September survey. Communities similar to the pre-drawdown Par Pond aquatic plant communities are becoming re-established; especially, beds of maidencane, lotus, waterlily, and watershield are now extensive and well established. Cattail occurrence continues to increase, but large beds common to Par Pond prior to the drawdown have not formed. Future surveys during the late growing seasons of 1995, and throughout 1996 and 1997, along with the evaluation of satellite data to map the areal extent of the macrophyte beds of Par Pond, are planned

Chemical Changes Induced by Irradiation in Meats and Meat Components; Transformations Chimiques Provoquees par les Rayonnements dans les Viandes et Leurs Constituants; Khimicheskie prevrashcheniya v myasnykh produktakh i ikh sostavnykh chastyakh pod vozdejstviem oblucheniya; Alteraciones Quimicas Producidas por Irradiacion de las Carnes y de sus Componentes

Energy Technology Data Exchange (ETDEWEB)

Merritt, C. Jr. [Pioneering Research Division, United States Army Natick Laboratories, Natick, MA (United States)

1966-11-15

The acceptability of meats preserved by irradiation has been hampered by the formation of an irradiation flavour and odour. This flavour and odour is believed to be due to the volatile chemical compounds produced by radiation impact on the protein and lipid molecules. The analysis of the volatile compounds has been accomplished, employing programmed cryogenic temperature gas chromatography for separation of the complex mixtures obtained, and rapid scanning mass spectrometry for identification of the individually separated components. Comprehensive analyses of the volatiles from irradiated ground beef, pork, mutton, lamb, and veal, as well as the volatile irradiation degradation products of several amino acids and proteins, animal fats, methyl esters of fatty acids, and triglycerides have been made. The results of the analysis of the irradiated component meat substances are compared with those obtained from the irradiation of meat itself, and of separate meat fractions, thus establishing the contribution of each fraction to the total. Mechanisms are postulated for the formation of the volatile components from each fraction and for interactions among intermediates from different fractions. (author) [French] La comestibilite des viandes conservees par les rayonnements s'est trouvee diminuee a la suite de l'apparition dans celles-ci d'un gout et d'une odeur engendres par l'irradiation. On pense que ces derniers sont dus aux composes chimiques volatils qui sont formes par l'action des rayonnements sur les molecules des proteines et des lipides. Il a ete procede a l'analyse des composes volatils a l'aide d'un programme de chromatographie en phase gazeuse a temperature cryogenique visant a separer les constituants des melanges complexes obtenus, et par spectrometrie de masse a balayage rapide destinee a identifier les constituants separes. L'auteur a effectue des analyses completes des composes volatils emanant de viande hachee de boeuf, de porc, de mouton, d'agneau et de

Improved Satellite-based Photosysnthetically Active Radiation (PAR) for Air Quality Studies

Science.gov (United States)

Pour Biazar, A.; McNider, R. T.; Cohan, D. S.; White, A.; Zhang, R.; Dornblaser, B.; Doty, K.; Wu, Y.; Estes, M. J.

2015-12-01

One of the challenges in understanding the air quality over forested regions has been the uncertainties in estimating the biogenic hydrocarbon emissions. Biogenic volatile organic compounds, BVOCs, play a critical role in atmospheric chemistry, particularly in ozone and particulate matter (PM) formation. In southeastern United States, BVOCs (mostly as isoprene) are the dominant summertime source of reactive hydrocarbon. Despite significant efforts in improving BVOC estimates, the errors in emission inventories remain a concern. Since BVOC emissions are particularly sensitive to the available photosynthetically active radiation (PAR), model errors in PAR result in large errors in emission estimates. Thus, utilization of satellite observations to estimate PAR can help in reducing emission uncertainties. Satellite-based PAR estimates rely on the technique used to derive insolation from satellite visible brightness measurements. In this study we evaluate several insolation products against surface pyranometer observations and offer a bias correction to generate a more accurate PAR product. The improved PAR product is then used in biogenic emission estimates. The improved biogenic emission estimates are compared to the emission inventories over Texas and used in air quality simulation over the period of August-September 2013 (NASA's Discover-AQ field campaign). A series of sensitivity simulations will be performed and evaluated against Discover-AQ observations to test the impact of satellite-derived PAR on air quality simulations.

SAFARI 2000 PAR Measurements, Kalahari Transect, Botswana, Wet Season 2000

Data.gov (United States)

National Aeronautics and Space Administration — Ceptometer data from a Decagon AccuPAR (Model PAR-80) were collected at four sites in Botswana during the SAFARI 2000 Kalahari Transect Wet Season Campaign (March,...

Lumbar lordosis and pars interarticularis fractures: a case-control study

International Nuclear Information System (INIS)

Bugg, William G.; Lewis, Mark; Juette, Arne; Cahir, John G.; Toms, Andoni P.

2012-01-01

The aim of this study is to examine the relationship between lumbar lordosis and pars interarticularis fractures. In this retrospective case-control study we compare the angle of lumbar lordosis and the angle of the S1 vertebral endplate (as a measure of pelvic tilt) in patients with bilateral L5 pars interarticularis fractures with age- and sex-matched control cases with normal MRI examinations of the lumbar spine. Twenty-nine cases of bilateral L5 pars interarticularis fractures with matched control-cases were identified on MRI (16 male, 13 female, age 9-63 years). The angle of lordosis was measured between the inferior L4 and superior S1 vertebral endplates on a standing lateral lumbar spine radiograph for both groups. The mean angle of lordosis about the L5 vertebra was 36.9 (SD = 6.5 ) in the pars interarticularis fracture group, and 30.1 (SD = 6.4 ) in the control group. The difference between the two groups was significant (mean difference 6.8 , Student's t test: P < 0.001). The mean angle of sacral tilt measured was 122.2 (SD = 10.16 ) for controls and 136.4 (SD = 10.86 ) for patients with pars defects. The difference in the means of 14.2 was statistically significantly different (P < 0.0001). Sacral tilt represented by a steeply angled superior endplate of S1 is associated with a significantly increased angle of lordosis, between L4 and S1, and pars fractures at L5. Steep angulation of the first sacral vertebral segment maybe the predisposing biomechanical factor that leads to pincer-like impingement of the pars interarticularis and then spondylolysis. (orig.)

Lumbar lordosis and pars interarticularis fractures: a case-control study

Energy Technology Data Exchange (ETDEWEB)

Bugg, William G; Lewis, Mark; Juette, Arne; Cahir, John G; Toms, Andoni P [Cotman Centre, Norwich Radiology Academy, Norwich, Norfolk (United Kingdom)

2012-07-15

The aim of this study is to examine the relationship between lumbar lordosis and pars interarticularis fractures. In this retrospective case-control study we compare the angle of lumbar lordosis and the angle of the S1 vertebral endplate (as a measure of pelvic tilt) in patients with bilateral L5 pars interarticularis fractures with age- and sex-matched control cases with normal MRI examinations of the lumbar spine. Twenty-nine cases of bilateral L5 pars interarticularis fractures with matched control-cases were identified on MRI (16 male, 13 female, age 9-63 years). The angle of lordosis was measured between the inferior L4 and superior S1 vertebral endplates on a standing lateral lumbar spine radiograph for both groups. The mean angle of lordosis about the L5 vertebra was 36.9 (SD = 6.5 ) in the pars interarticularis fracture group, and 30.1 (SD = 6.4 ) in the control group. The difference between the two groups was significant (mean difference 6.8 , Student's t test: P < 0.001). The mean angle of sacral tilt measured was 122.2 (SD = 10.16 ) for controls and 136.4 (SD = 10.86 ) for patients with pars defects. The difference in the means of 14.2 was statistically significantly different (P < 0.0001). Sacral tilt represented by a steeply angled superior endplate of S1 is associated with a significantly increased angle of lordosis, between L4 and S1, and pars fractures at L5. Steep angulation of the first sacral vertebral segment maybe the predisposing biomechanical factor that leads to pincer-like impingement of the pars interarticularis and then spondylolysis. (orig.)

Lumbar lordosis and pars interarticularis fractures: a case-control study

Energy Technology Data Exchange (ETDEWEB)

Bugg, William G.; Lewis, Mark; Juette, Arne; Cahir, John G.; Toms, Andoni P. [Cotman Centre, Norwich Radiology Academy, Norwich, Norfolk (United Kingdom)

2012-07-15

The aim of this study is to examine the relationship between lumbar lordosis and pars interarticularis fractures. In this retrospective case-control study we compare the angle of lumbar lordosis and the angle of the S1 vertebral endplate (as a measure of pelvic tilt) in patients with bilateral L5 pars interarticularis fractures with age- and sex-matched control cases with normal MRI examinations of the lumbar spine. Twenty-nine cases of bilateral L5 pars interarticularis fractures with matched control-cases were identified on MRI (16 male, 13 female, age 9-63 years). The angle of lordosis was measured between the inferior L4 and superior S1 vertebral endplates on a standing lateral lumbar spine radiograph for both groups. The mean angle of lordosis about the L5 vertebra was 36.9 (SD = 6.5 ) in the pars interarticularis fracture group, and 30.1 (SD = 6.4 ) in the control group. The difference between the two groups was significant (mean difference 6.8 , Student's t test: P < 0.001). The mean angle of sacral tilt measured was 122.2 (SD = 10.16 ) for controls and 136.4 (SD = 10.86 ) for patients with pars defects. The difference in the means of 14.2 was statistically significantly different (P < 0.0001). Sacral tilt represented by a steeply angled superior endplate of S1 is associated with a significantly increased angle of lordosis, between L4 and S1, and pars fractures at L5. Steep angulation of the first sacral vertebral segment maybe the predisposing biomechanical factor that leads to pincer-like impingement of the pars interarticularis and then spondylolysis. (orig.)

Recent applications of gas chromatography with high-resolution mass spectrometry.

Science.gov (United States)

Špánik, Ivan; Machyňáková, Andrea

2018-01-01

Gas chromatography coupled to high-resolution mass spectrometry is a powerful analytical method that combines excellent separation power of gas chromatography with improved identification based on an accurate mass measurement. These features designate gas chromatography with high-resolution mass spectrometry as the first choice for identification and structure elucidation of unknown volatile and semi-volatile organic compounds. Gas chromatography with high-resolution mass spectrometry quantitative analyses was previously focused on the determination of dioxins and related compounds using magnetic sector type analyzers, a standing requirement of many international standards. The introduction of a quadrupole high-resolution time-of-flight mass analyzer broadened interest in this method and novel applications were developed, especially for multi-target screening purposes. This review is focused on the development and the most interesting applications of gas chromatography coupled to high-resolution mass spectrometry towards analysis of environmental matrices, biological fluids, and food safety since 2010. The main attention is paid to various approaches and applications of gas chromatography coupled to high-resolution mass spectrometry for non-target screening to identify contaminants and to characterize the chemical composition of environmental, food, and biological samples. The most interesting quantitative applications, where a significant contribution of gas chromatography with high-resolution mass spectrometry over the currently used methods is expected, will be discussed as well. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

ParTIES: a toolbox for Paramecium interspersed DNA elimination studies.

Science.gov (United States)

Denby Wilkes, Cyril; Arnaiz, Olivier; Sperling, Linda

2016-02-15

Developmental DNA elimination occurs in a wide variety of multicellular organisms, but ciliates are the only single-celled eukaryotes in which this phenomenon has been reported. Despite considerable interest in ciliates as models for DNA elimination, no standard methods for identification and characterization of the eliminated sequences are currently available. We present the Paramecium Toolbox for Interspersed DNA Elimination Studies (ParTIES), designed for Paramecium species, that (i) identifies eliminated sequences, (ii) measures their presence in a sequencing sample and (iii) detects rare elimination polymorphisms. ParTIES is multi-threaded Perl software available at https://github.com/oarnaiz/ParTIES. ParTIES is distributed under the GNU General Public Licence v3. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Effect of simvastatin and ezetimibe on suPAR levels and outcomes

DEFF Research Database (Denmark)

Hodges, Gethin W; Bang, Casper N; Forman, Julie L

2018-01-01

-lowering therapy also lowers suPAR levels is unknown. METHODS: We investigated whether treatment with Simvastatin 40 mg and Ezetimibe 10 mg lowered plasma suPAR levels in 1838 patients with mild-moderate, asymptomatic aortic stenosis, included in the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study, using...... and Ezetimibe treatment impeded the progression of the time-related increase in plasma suPAR levels. Year-1 suPAR was associated with all-cause mortality, MCE, and AVE irrespective of baseline levels (SEAS study: NCT00092677)....... cardiovascular events (MCE) composed of ischemic cardiovascular events (ICE) and aortic valve related events (AVE). RESULTS: After 4.3 years of follow-up, suPAR levels had increased by 9.2% (95% confidence interval [CI]: 7.0%-11.5%) in the placebo group, but only by 4.1% (1.9%-6.2%) in the group with lipid...

The Utilization of Background Spectrum to Calibrate Gamma Spectrometry

International Nuclear Information System (INIS)

Mahrouka, M. M.; Mutawa, A. M.

2004-01-01

Many developed countries have very poor reference standards to calibrate their nuclear instrumentations or may find some difficulties to obtain a reference standard. In this work a simple way for Gamma spectrometry calibration was developed. The method depends on one reference point and additional points from the background. The two derived equations were applied to the analyses of radioactive nuclides in soil and liquid samples prepared by IAEA laboratories through AL MERA Project. The results showed the precision of the methodology used, as well as, the possibility of using some points in the background spectrum as a replacement for reference standards of Gamma spectrometry calibration. (authors)

Paracrine Apoptotic Effect of p53 Mediated by Tumor Suppressor Par-4

Directory of Open Access Journals (Sweden)

Ravshan Burikhanov

2014-01-01

Full Text Available The guardian of the genome, p53, is often mutated in cancer and may contribute to therapeutic resistance. Given that p53 is intact and functional in normal tissues, we harnessed its potential to inhibit the growth of p53-deficient cancer cells. Specific activation of p53 in normal fibroblasts selectively induced apoptosis in p53-deficient cancer cells. This paracrine effect was mediated by p53-dependent secretion of the tumor suppressor Par-4. Accordingly, the activation of p53 in normal mice, but not p53−/− or Par-4−/− mice, caused systemic elevation of Par-4, which induced apoptosis of p53-deficient tumor cells. Mechanistically, p53 induced Par-4 secretion by suppressing the expression of its binding partner, UACA, which sequesters Par-4. Thus, normal cells can be empowered by p53 activation to induce Par-4 secretion for the inhibition of therapy-resistant tumors.

Minicomputer system for radiochemical analysis by coincidence spectrometry

International Nuclear Information System (INIS)

Brauer, F.P.; Fager, J.E.

1979-01-01

Minicomputer-based coincidence analysis methods have been developed for use in performing radiochemical analysis by high-resolution x- and gamma-ray coincidence spectrometry. This paper describes the data-acquisition and analysis methods develolped for qualitative and quantitative analyses of coincidence spectrometric data. Data-acquisition capabilities include both direct multiparameter pulse-height analysis and buffered list-mode acquisition

Efficacy and safety of the pars plana clip in the Ahmed valve device inserted via the pars plana in patients with refractory glaucoma

Directory of Open Access Journals (Sweden)

Manuel Diaz-Llopis

2010-05-01

Full Text Available Manuel Diaz-Llopis1,2,3, David Salom1,3, Salvador García-Delpech1,2,3, Patricia Udaondo1,3, Jose Maria Millan3,5, J Fernando Arevalo61Department of Ophthalmology, La Fe University Hospital of Valencia, Valencia, Spain; 2Department of Ophthalmology of the Valencia University, Valencia, Spain; 3Biomedical Network Research Centre on Rare Diseases (CIBERER, Valencia, Spain; 4Catholic University San Vicente Martir, Valencia, Spain; 5Department of Genetics, La Fe University Hospital of Valencia, Valencia, Spain; 6Clinica Oftalmologica Centro Caracas, Retina and VItreous Service, Caracas, DC, VenezuelaPurpose: To evaluate the efficacy and safety of the pars plana clip (PPC in the Ahmed valve tube inserted via the pars plana in patients with secondary refractory glaucomas.Methods: Prospective and interventional case series that included 10 patients with secondary refractory glaucoma. The pars plana vitrectomy and the implant of the modified tube were performed during the same surgery. Control of intraocular pressure (IOP and the development of intra- and postoperative complications were evaluated during the follow-up.Results: Follow-up time was twelve months in all the patients. Control of IOP was achieved in 90% of patients, and 70% needed no antiglaucoma treatment. The complications that occurred were transient hypotony in three cases, choroidal detachment in two cases, and one case of intraocular hemorrhage. No case of tube extrusion or tube kink was observed.Conclusions: Our data suggests that implantation of the Ahmed tube modified with the PPC via the pars plana is safe and effective in patients with secondary refractory glaucomas. Keywords: pars plana clip, Ahmed valve, refractory glaucoma, pars plana vitrectomy

Effects of solar PAR and UV radiation on tropical biofouling communities

KAUST Repository

Dobretsov, SV

2010-03-08

We investigated the effect of solar ultraviolet radiation (UVR) and photosynthetically active radiation (PAR) on the development of tropical micro- and macrofouling communities for 30 d. The experimental design involved 3 treatments: full spectrum (PAR+UVR), PAR only, and minimal light (reduced PAR and UVR). Terminal restriction fragment length polymorphism analysis demonstrated that different light conditions resulted in the formation of highly different microbial communities. The lowest densities of bacteria were found under the full spectrum treatment, while the lowest densities of diatoms were found in the minimal light treatment. Macrofouling communities consisted of 13 species and differed among light treatments. In the presence of UVR, communities had low species diversity, evenness, and richness, while in minimal light and PAR treatments, communities had high species diversity, evenness, and richness. Similarity percentage (SIMPER) analysis revealed that the tubeworm Hydroides elegans, the alga Ulva (Enteromorpha) sp., and the bivalve Perna viridis were the species responsible for most of the dissimilarities in macrofouling communities among treatments. While densities of H. elegans were similar in the PAR and minimal light treatments, this polychaete had higher growth rates under minimal light conditions. We conclude that UVR and PAR directly control the development of shallow micro- and macrofouling communities by inhibiting the recruitment and growth of sensitive species and promoting the growth of resistant species, but also that these forms of solar radiation influence the surface cues available to competent larvae by altering the development of the microbial community.

Par Pond vegetation status Summer 1995 -- June survey descriptive summary

International Nuclear Information System (INIS)

Mackey, H.E. Jr.; Riley, R.S.

1995-06-01

The water level of Par Pond was lowered approximately 20 feet in mid-1991 in order to protect downstream residents from possible dam failure suggested by subsidence on the downstream slope of the dam and to repair the dam. This lowering exposed both emergent and nonemergent macrophyte beds to drying conditions resulting in extensive losses. A survey of the shoreline aquatic plant communities in June 1995, three months after the refilling of Par Pond to approximately 200 feet above mean sea level, indicated that much of the original plant communities and the intermediate shoreline communities present on the exposed sediments have been lost. The extensive old-field and emergent marsh communities that were present on the exposed shoreline during the drawdown have been flooded and much of the pre-drawdown Par Pond aquatic plant communities have not had sufficient time for re-establishment. The shoreline does, however, have extensive beds of maidencane which extend from the shoreline margin to areas as deep as 2 and perhaps 3 meters. Scattered individual plants of lotus and watershield are common and may indicate likely directions of future wetland development in Par Pond. In addition, within isolated coves, which apparently received ground water seepage and/or stream surface flows during the period of the Par Pond draw down, extensive beds of waterlilies and spike rush are common. Invasion of willow and red maple occurred along the lake shoreline as well. Although not absent from this survey, evidence of the extensive redevelopment of the large cattail and eel grass beds was not observed in this first survey of Par Pond. Future surveys during the growing seasons of 1995, 1996, and 1997 along with the evaluation of satellite date to map the areal extent of the macrophyte beds of Par Pond are planned

Analytical methods used in plutonium purification cycles by trilaurylamine; Methodes analytiques utilisees dans les cycles de purification du plutonium par la trilaurylamine

Energy Technology Data Exchange (ETDEWEB)

Perez, J J [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1965-07-01

The utilisation of trilaurylamine as a solvent extractant for the purification of plutonium has entailed to perfect a set of analytical methods which involves, various techniques. The organic impurities of the solvent can be titrated by gas-liquid chromatography. The titration of the main degradation product, the di-laurylamine, can be accomplished also by spectro-colorimetry. Potentiometry is used for the analysis of the different salts of amine-nitrate-sulfate-bisulfate as also the extracted nitric acid. The determination of the nitrate in aqueous phase is carried out by constant current potentiometry. The range of application, the accuracy and the procedure of these analysis are related in the present report. (author) [French] L'utilisation de la trilaurylamine comme solvant d'extraction pour la purification du plutonium a necessite la mise au point d'un ensemble de methodes analytiques qui ressortent de techniques diverses. Les impuretes organiques du solvant peuvent etre dosees par chromatographie gaz-liquide. Le dosage du principal produit de degradation, la dilaurylamine, peut egalement etre effectue par spectrocolorimetrie. La potentiometrie est utilisee pour les analyses des differents sels d'amine: nitrate, sulfate, bisulfate, ainsi que de l'acide nitrique extrait. La determination des nitrates en phase aqueuse est executee par potentiometrie a courant impose. Le domaine d'application, la precision et le mode operatoire de ces analyses sont indiques dans le present rapport. (auteur)

Mass spectrometry in identification of ecotoxicants including chemical and biological warfare agents

International Nuclear Information System (INIS)

Lebedev, Albert T.

2005-01-01

Mass spectrometry is a unique tool to detect and identify trace levels of organic and bioorganic compounds as well as microorganisms in the environment. The range of potential chemical warfare (CW) and biological warfare (BW) agents is very broad. An important advantage of mass spectrometry over other techniques involves potential for full spectrum detection of chemical and biological agents including mid-spectrum materials (i.e. bioactive peptides, toxins, etc.) for which biological approaches are inadequate. Being very fast (seconds and minutes), extremely sensitive (zeptomoles 10 -21 ), and informative (detailed qualitative and quantitative composition of mixtures containing hundreds of chemicals), mass spectrometry is a principal analytical tool at the sites of destruction of CW. Due to its unique features, mass spectrometry is applied not only for the detection of CW agents, but for the analysis of products of metabolism and degradation of these agents in organisms or environment as well. The present paper deals with some examples of successful application of mass spectrometry for the analyses of ecotoxicants, chemical warfare agents, explosives, and microorganisms including biology warfare agents

Bacterial mitosis: Partitioning protein ParA oscillates in spiral-shaped structures and positions plasmids at mid-cell

DEFF Research Database (Denmark)

Ebersbach, G.; Gerdes, Kenn

2004-01-01

The par2 locus of Escherichia coli plasmid pB171 encodes oscillating ATPase ParA, DNA binding protein ParB and two cis-acting DNA regions to which ParB binds (parC1 and parC2). Three independent techniques were used to investigate the subcellular localization of plasmids carrying par2. In cells......A-GFP oscillated in spiral-shaped structures. Amino acid substitutions in ParA simultaneously abolished ParA spiral formation, oscillation and either plasmid localization or plasmid separation at mid-cell. Therefore, our results suggest that ParA spirals position plasmids at the middle of the bacterial nucleoid...

Further development of IDGS: Isotope dilution gamma-ray spectrometry

International Nuclear Information System (INIS)

Li, T.K.; Parker, J.L.; Kuno, Y.; Sato, S.; Kamata, M.; Akiyama, T.

1991-01-01

The isotope dilution gamma-ray spectrometry (IDGS) technique for determining the plutonium concentration and isotopic composition of highly radioactive spent-fuel dissolver solutions has been further developed. Both the sample preparation and the analysis have been improved. The plutonium isotopic analysis is based on high-resolution, low-energy gamma-ray spectrometry. The plutonium concentration in the dissolver solutions then is calculated from the measured isotopic differences among the spike, the dissolver solution, and the spiked dissolver solution. Plutonium concentrations and isotopic compositions of dissolver solutions analyzed from this study agree well with those obtained by traditional isotope dilution mass spectrometry (IDMS) and are consistent with the first IDGS experimental result. With the current detector efficiency, sample size, and a 100-min count time, the estimated precision is ∼0.5% for 239 Pu and 240 Pu isotopic analyses and ∼1% for the plutonium concentration analysis. 5 refs., 2 figs., 7 tabs

TMS suppression of right pars triangularis, but not pars opercularis, improves naming in aphasia

Science.gov (United States)

Naeser, Margaret A.; Martin, Paula I.; Theoret, Hugo; Kobayashi, Masahito; Fregni, Felipe; Nicholas, Marjorie; Tormos, Jose M.; Steven, Megan S.; Baker, Errol H.; Pascual-Leone, Alvaro

2011-01-01

This study sought to discover if an optimum 1 cm2 area in the non-damaged right hemisphere (RH) was present, which could temporarily improve naming in chronic, nonfluent aphasia patients when suppressed with repetitive transcranial magnetic stimulation (rTMS). Ten minutes of slow, 1 Hz rTMS was applied to suppress different RH ROIs in eight aphasia cases. Picture naming and response time (RT) were examined before, and immediately after rTMS. In aphasia patients, suppression of right pars triangularis (PTr) led to significant increase in pictures named, and significant decrease in RT. Suppression of right pars opercularis (POp), however, led to significant increase in RT, but no change in number of pictures named. Eight normals named all pictures correctly; similar to aphasia patients, RT significantly decreased following rTMS to suppress right PTr, versus right POp. Differential effects following suppression of right PTr versus right POp suggest different functional roles for these regions. PMID:21864891

The future of the accelerator mass spectrometry of rare long-lived radioactive isotopes

International Nuclear Information System (INIS)

Litherland, A.E.

1990-01-01

Accelerators, originally designed for nuclear physics, can be added to mass spectrometric apparatus to increase the sensitivity so that isotope ratios in the range 10 -12 to 10 -15 can be measured routinely. This significant improvement of high-sensitivity mass spectrometry has been called Accelerator Mass Spectrometry. The present article addresses the basic principles of accelerator mass spectrometry and some recent applications which show its versatility. In particular, it is noted that accelerator mass spectrometry could play an increasing role in the measurement of the levels of long lived radioactivities in the environment, including the actinides, which result from human activities such as the use of nuclear power. To fulfill this promise, continued research and development is necessary to provide ion sources, various types of heavy ion accelerators and peripheral magnetic and electric analysers. (N.K.)

First-in-human uPAR PET: Imaging of Cancer Aggressiveness

Science.gov (United States)

Persson, Morten; Skovgaard, Dorthe; Brandt-Larsen, Malene; Christensen, Camilla; Madsen, Jacob; Nielsen, Carsten H.; Thurison, Tine; Klausen, Thomas Levin; Holm, Søren; Loft, Annika; Berthelsen, Anne Kiil; Ploug, Michael; Pappot, Helle; Brasso, Klaus; Kroman, Niels; Højgaard, Liselotte; Kjaer, Andreas

2015-01-01

A first-in-human clinical trial with Positron Emission Tomography (PET) imaging of the urokinase-type plasminogen activator receptor (uPAR) in patients with breast, prostate and bladder cancer, is described. uPAR is expressed in many types of human cancers and the expression is predictive of invasion, metastasis and indicates poor prognosis. uPAR PET imaging therefore holds promise to be a new and innovative method for improved cancer diagnosis, staging and individual risk stratification. The uPAR specific peptide AE105 was conjugated to the macrocyclic chelator DOTA and labeled with 64Cu for targeted molecular imaging with PET. The safety, pharmacokinetic, biodistribution profile and radiation dosimetry after a single intravenous dose of 64Cu-DOTA-AE105 were assessed by serial PET and computed tomography (CT) in 4 prostate, 3 breast and 3 bladder cancer patients. Safety assessment with laboratory blood screening tests was performed before and after PET ligand injection. In a subgroup of the patients, the in vivo stability of our targeted PET ligand was determined in collected blood and urine. No adverse or clinically detectable side effects in any of the 10 patients were found. The ligand exhibited good in vivo stability and fast clearance from plasma and tissue compartments by renal excretion. In addition, high uptake in both primary tumor lesions and lymph node metastases was seen and paralleled high uPAR expression in excised tumor tissue. Overall, this first-in-human study therefore provides promising evidence for safe use of 64Cu-DOTA-AE105 for uPAR PET imaging in cancer patients. PMID:26516369

Rat beta-LPH, gamma-LPH and beta-endorphin biosynthesized by isolated cells of pars intermedia and pars distalis

International Nuclear Information System (INIS)

Gianoulakis, C.; Seidah, N.G.; Routhier, R.; Chretien, M.

1980-01-01

Rats pars intermedia cells were incubated for 3 h with the following amino-acids: a) 35 S-methionine and 3 H-phenylalamine; b) 3 H-valine; and c) 3 H-valine and 3 H-lysine. Radioactive gamma-lipotropin, beta-lipotropin and beta-endorphin were purified on carboxy- methyl-cellulose and characterized by polyacrylamide disc gel electrophoresis af pH 4.5, molecular weight estimation and microsequencing. Rat gamma-lipotropin was shown to differ slightly from ovine gamma-lipotropin in its NH 2 -terminal amino acid sequence, in containing no methionine and having phenylalanine at position 6, valine at positions 13 and 27, and lysine at position 20. The same variations were observed in the sequence of rat beta-lipotropin, while rat beta-endorphin was shown to be identical to the ovine beta-endorphin. Following a 3-h pulse of rat pars distalis, the cells were extracted with care to avoid beta-lipotropin degradation by proteolytic enzymes. A peptide was purified and identified to be rat beta-endorphin, thus demonstrating that beta-endorphin is biosynthesized in pars distalis and is not an extraction artifact. (author)

Socioeconomic diagnosis of cheese producers of Marajó, state of Pará, Brazil

Directory of Open Access Journals (Sweden)

Vitória Nazaré Costa Seixas

2014-10-01

Full Text Available The aim of this research was to diagnose the socioeconomic conditions of cheese producers from three municipalities of Marajó Island, Pará state, Brazil. Manufacture process, hygienic-sanitary conditions in handmade cheese production and its commercialization were some features analysed for both cream-type and butter-type cheeses. During the survey, conducted from March to September 2012 questionnaires were applied to ten Marajó’s cheese producers. The cheese fabrication was characterized as a handmade process, employing family labor, most over ten years of experience. The production has a small scale, uses rudimentary technologies, lacks proper infrastructure for the processing of the product and has unsatisfactory hygienic-sanitary conditions. Commercialization is mainly by direct sale on the ship that travels to Belém city, capital of Pará state. Interviewed producers showed good reception to knowledge that can improve quality of the product, but they need a better guidance. In this context, the transfer of information is essential to sustain the production of these cheeses and preserve local culture, contributing to the economic and social development of producers regions.

Identification of a new epitope in uPAR as a target for the cancer therapeutic monoclonal antibody ATN-658, a structural homolog of the uPAR binding integrin CD11b (αM.

Directory of Open Access Journals (Sweden)

Xiang Xu

Full Text Available The urokinase plasminogen activator receptor (uPAR plays a role in tumor progression and has been proposed as a target for the treatment of cancer. We recently described the development of a novel humanized monoclonal antibody that targets uPAR and has anti-tumor activity in multiple xenograft animal tumor models. This antibody, ATN-658, does not inhibit ligand binding (i.e. uPA and vitronectin to uPAR and its mechanism of action remains unclear. As a first step in understanding the anti-tumor activity of ATN-658, we set out to identify the epitope on uPAR to which ATN-658 binds. Guided by comparisons between primate and human uPAR, epitope mapping studies were performed using several orthogonal techniques. Systematic site directed and alanine scanning mutagenesis identified the region of aa 268-275 of uPAR as the epitope for ATN-658. No known function has previously been attributed to this epitope Structural insights into epitope recognition were obtained from structural studies of the Fab fragment of ATN-658 bound to uPAR. The structure shows that the ATN-658 binds to the DIII domain of uPAR, close to the C-terminus of the receptor, corroborating the epitope mapping results. Intriguingly, when bound to uPAR, the complementarity determining region (CDR regions of ATN-658 closely mimic the binding regions of the integrin CD11b (αM, a previously identified uPAR ligand thought to be involved in leukocyte rolling, migration and complement fixation with no known role in tumor progression of solid tumors. These studies reveal a new functional epitope on uPAR involved in tumor progression and demonstrate a previously unrecognized strategy for the therapeutic targeting of uPAR.

The protein kinase SIK downregulates the polarity protein Par3

DEFF Research Database (Denmark)

Vanlandewijck, Michael; Dadras, Mahsa Shahidi; Lomnytska, Marta

2018-01-01

on Par3. Functionally, this mechanism impacts on tight junction downregulation. Furthermore, SIK contributes to the loss of epithelial polarity and examination of advanced and invasive human cancers of diverse origin displayed high levels of SIK expression and a corresponding low expression of Par3...

PET imaging of urokinase-type plasminogen activator receptor (uPAR) in prostate cancer

DEFF Research Database (Denmark)

Skovgaard, Dorthe; Persson, Morten; Kjaer, Andreas

2016-01-01

Overexpression of urokinase-type plasminogen activator receptors (uPAR) represents an important biomarker for aggressiveness in most common malignant diseases, including prostate cancer (PC). Accordingly, uPAR expression either assessed directly in malignant PC tissue or assessed directly in plasma...... and prognostic imaging method. In this review, we will focus on the recent development of uPAR PET and the relevance within prostate cancer imaging. Novel antibody and small-molecule radiotracers-targeting uPAR, including a series of uPAR-targeting PET ligands, based on the high affinity peptide ligand AE105......, have been synthesized and tested in vitro and in vivo in preclinical murine xenograft models and, recently, in a first-ever clinical uPAR PET study in cancer patients, including patients with PC. In this phase I study, a high and specific uptake of the tracer 64Cu-DOTA-AE105 was found in both primary...

Determination of rare-earth elements in rocks by isotope-excited X-ray fluorescence spectrometry

DEFF Research Database (Denmark)

Kunzendorf, Helmar; Wollenberg, H.A.

1970-01-01

Isotope-excited X-ray fluorescence spectrometry furnishes a rapid determination of rare-earth elements in unprepared rock samples. The samples are excited by 241Am γ-rays, generating X-ray spectra on a multichannel pulse-height analyser. Gaussian peaks of the Kα and Kβ X-ray energies are treated ......-ray spectrometric scan of a longitudinally sliced drill core showed a close correlation between rare-earth abundances and appropriate minerals.......Isotope-excited X-ray fluorescence spectrometry furnishes a rapid determination of rare-earth elements in unprepared rock samples. The samples are excited by 241Am γ-rays, generating X-ray spectra on a multichannel pulse-height analyser. Gaussian peaks of the Kα and Kβ X-ray energies are treated...

Electron spin resonance and E.N.D.O.R. double resonance study of free radicals produced by gamma irradiation of imidazole single crystals; Etude par resonance paramagnetique electronique et double resonance E.N.D.O.R. des radicaux libres crees par irradiation gamma de monocristaux d'imidazole

Energy Technology Data Exchange (ETDEWEB)

Lamotte, B [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1970-07-01

Gamma irradiation of imidazole single crystals at 300 deg. K gives two radicals. Identification and detailed studies of their electronic and geometric structure have been made by ESR and ENDOR techniques. A study of the hydrogen bonded protons hyperfine tensor is made and let us conclude to the inexistence of movement and tunneling of these protons. The principal low temperature radical, produced by gamma irradiation at 77 deg. K has been also studied by ESR and a model has been proposed. (author) [French] L'irradiation gamma de monocristaux d'imidazole a 300 deg. K conduit a deux radicaux dont l'identification et l'etude detaillee des structures electroniques et geometriques ont ete obtenues par la resonance paramagnetique electronique (RPE) et la double resonance ENDOR. En particulier l'examen des protons de la liaison hydrogene permet de conclure, pour ceux-ci, a l'inexistence de tout mouvement par effet tunnel. De plus, l'analyse des spectres de RPE du radical principal cree par irradiation gamma de l'imidazole a 77 deg. K nous a permis de proposer un modele pour ce radical. (auteur)

Comparison of a portable micro-X-ray fluorescence spectrometry with inductively coupled plasma atomic emission spectrometry for the ancient ceramics analysis

International Nuclear Information System (INIS)

Papadopoulou, D.N.; Zachariadis, G.A.; Anthemidis, A.N.; Tsirliganis, N.C.; Stratis, J.A.

2004-01-01

Two multielement instrumental methods of analysis, micro X-ray fluorescence spectrometry (micro-XRF) and inductively coupled plasma atomic emission spectrometry (ICP-AES) were applied for the analysis of 7th and 5th century B.C. ancient ceramic sherds in order to evaluate the above two methods and to assess the potential to use the current compact and portable micro-XRF instrument for the in situ analysis of ancient ceramics. The distinguishing factor of interest is that micro-XRF spectrometry offers the possibility of a nondestructive analysis, an aspect of primary importance in the compositional analysis of cultural objects. Micro-XRF measurements were performed firstly directly on the ceramic sherds with no special pretreatment apart from surface cleaning (micro-XRF on sherds) and secondly on pressed pellet disks which were prepared for each ceramic sherd (micro-XRF on pellet). For the ICP-AES determination of elements, test solutions were prepared by the application of a microwave-assisted decomposition procedure in closed high-pressure PFA vessels. Also, the standard reference material SARM 69 was used for the efficiency calibration of the micro-XRF instrument and was analysed by both methods. In order to verify the calibration, the standard reference materials NCS DC 73332 and SRM620 as well as the reference materials AWI-1 and PRI-1 were analysed by micro-XRF. Elemental concentrations determined by the three analytical procedures (ICP-AES, micro-XRF on sherds and micro-XRF on pellets) were statistically treated by correlation analysis and Student's t-test (at the 95% confidence level)

Comparison of a portable micro-X-ray fluorescence spectrometry with inductively coupled plasma atomic emission spectrometry for the ancient ceramics analysis

Energy Technology Data Exchange (ETDEWEB)

Papadopoulou, D.N. [Laboratory of Analytical Chemistry, Faculty of Chemistry, Aristotle University, GR-54124, Thessaloniki (Greece); Zachariadis, G.A. [Laboratory of Analytical Chemistry, Faculty of Chemistry, Aristotle University, GR-54124, Thessaloniki (Greece); Anthemidis, A.N. [Laboratory of Analytical Chemistry, Faculty of Chemistry, Aristotle University, GR-54124, Thessaloniki (Greece); Tsirliganis, N.C. [Archaeometry Laboratory, Cultural and Educational Technology Institute, Tsimiski 58, GR-67100, Xanthi (Greece); Stratis, J.A. [Laboratory of Analytical Chemistry, Faculty of Chemistry, Aristotle University, GR-54124, Thessaloniki (Greece)]. E-mail: jstratis@chem.auth.gr

2004-12-01

Two multielement instrumental methods of analysis, micro X-ray fluorescence spectrometry (micro-XRF) and inductively coupled plasma atomic emission spectrometry (ICP-AES) were applied for the analysis of 7th and 5th century B.C. ancient ceramic sherds in order to evaluate the above two methods and to assess the potential to use the current compact and portable micro-XRF instrument for the in situ analysis of ancient ceramics. The distinguishing factor of interest is that micro-XRF spectrometry offers the possibility of a nondestructive analysis, an aspect of primary importance in the compositional analysis of cultural objects. Micro-XRF measurements were performed firstly directly on the ceramic sherds with no special pretreatment apart from surface cleaning (micro-XRF on sherds) and secondly on pressed pellet disks which were prepared for each ceramic sherd (micro-XRF on pellet). For the ICP-AES determination of elements, test solutions were prepared by the application of a microwave-assisted decomposition procedure in closed high-pressure PFA vessels. Also, the standard reference material SARM 69 was used for the efficiency calibration of the micro-XRF instrument and was analysed by both methods. In order to verify the calibration, the standard reference materials NCS DC 73332 and SRM620 as well as the reference materials AWI-1 and PRI-1 were analysed by micro-XRF. Elemental concentrations determined by the three analytical procedures (ICP-AES, micro-XRF on sherds and micro-XRF on pellets) were statistically treated by correlation analysis and Student's t-test (at the 95% confidence level)

Radiocarbon analyses along the EDML ice core in Antarctica

NARCIS (Netherlands)

van de Wal, R.S.W.; Meijer, H.A.J.; van Rooij, M.; van der Veen, C.

2007-01-01

Samples, 17 in total, from the EDML core drilled at Kohnen station Antarctica are analysed for 14CO and 14CO2 with a dry-extraction technique in combination with accelerator mass spectrometry. Results of the in situ produced 14CO fraction show a very low concentration of in situ produced 14CO.

Radiocarbon analyses along the EDML ice core in Antarctica

NARCIS (Netherlands)

Van de Wal, R. S. W.; Meijer, H. A. J.; De Rooij, M.; Van der Veen, C.

Samples, 17 in total, from the EDML core drilled at Kohnen station Antarctica are analysed for (CO)-C-14 and (CO2)-C-14 with a dry-extraction technique in combination with accelerator mass spectrometry. Results of the in situ produced (CO)-C-14 fraction show a very low concentration of in situ

The allure of mass spectrometry: From an earlyday chemist's perspective.

Science.gov (United States)

Tőkés, László

2017-07-01

sensitivity TCDD analyses and other projects. Reflecting on my services for the mass spectrometry society, involvements with the co-founding and 12 year chairing of the Asilomar Conference on Mass Spectrometry and founding of the Bay Area Mass Spectrometry regional MS discussion group, as part of my services for the mass spectrometry community, are presented in some detail. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 36:520-542, 2017. © 2016 The Authors. Mass Spectrometry Reviews Published by Wiley Periodicals, Inc.

Par3L enhances colorectal cancer cell survival by inhibiting Lkb1/AMPK signaling pathway

International Nuclear Information System (INIS)

Li, Taiyuan; Liu, Dongning; Lei, Xiong; Jiang, Qunguang

2017-01-01

Partitioning defective 3-like protein (Par3L) is a recently identified cell polarity protein that plays an important role in mammary stem cell maintenance. Previously, we showed that high expression of Par3L is associated with poor survival in malignant colorectal cancer (CRC), but the underlying mechanism remained unknown. To this end, we established a Par3L knockout colorectal cancer cell line using the CRISPR/Cas system. Interestingly, reduced proliferation, enhanced cell death and caspase-3 activation were observed in Par3L knockout (KO) cells as compared with wildtype (WT) cells. Consistent with previous studies, we showed that Par3L interacts with a tumor suppressor protein liver kinase B1 (Lkb1). Moreover, Par3L depletion resulted in abnormal activation of Lkb1/AMPK signaling cascade. Knockdown of Lkb1 in these cells could significantly reduce AMPK activity and partially rescue cell death caused by Par3L knockdown. Furthermore, we showed that Par3L KO cells were more sensitive to chemotherapies and irradiation. Together, these results suggest that Par3L is essential for colorectal cancer cell survival by inhibiting Lkb1/AMPK signaling pathway, and is a putative therapeutic target for CRC. - Highlights: • Par3L knockout using the CRISPR/Cas system induces apoptosis in colorectal cancer cells. • Par3L interacts with Lkb1 and regulates the activity of AMPK signaling cascade. • Par3L knockout cells are more sensitive to treatment of different chemotherapy drugs and irradiation.

Ultra-sensitive radionuclide spectrometry. Radiometrics and mass spectrometry synergy

International Nuclear Information System (INIS)

Povinec, P.P.

2005-01-01

Recent developments in radiometrics and mass spectrometry techniques for ultra-sensitive analysis of radionuclides in the marine environment are reviewed. In the radiometrics sector the dominant development has been the utilization of large HPGe detectors in underground laboratories with anti-cosmic or anti-Compton shielding for the analysis of short and medium-lived radionuclides in the environment. In the mass spectrometry sector, applications of inductively coupled plasma mass spectrometry (ICP-MS) and accelerator mass spectrometry (AMS) for the analysis of long-lived radionuclides in the environment are the most important recent achievements. The recent developments do not only considerably decrease the detection limits for several radionuclides (up to several orders of magnitude), but they also enable to decrease sample volumes so that sampling, e.g., of the water column can be much easier and more effective. A comparison of radiometrics and mass spectrometry results for the analysis of radionuclides in the marine environment shows a reasonable agreement - within quoted uncertainties, for wide range of activities and different sample matrices analyzed. (author)

Profils des enfants infectes par le vih en debut du traitement ...

African Journals Online (AJOL)

But : Décrire les profils des enfants infectés par le VIH au début du traitement antirétroviral. Matériels et méthode: Les dossiers des enfants infectés par le VIH dans la région maritime ont été analysés de mai 2008 à février 2010 par le comité thérapeutique. Résultats: Parmi les 96 dossiers analysés, 66,67% venaient du ...

Radiogas chromatography mass spectrometry in the selected ion monitoring mode

International Nuclear Information System (INIS)

Doerfler, D.L.; Rosenblum, E.R.; Malloy, J.M.; Naworal, J.D.; McManus, I.R.; Campbell, I.M.

1980-01-01

The value of selected ion monitoring in analyzing biological radio isotope incorporation experiments by radiogas chromatography mass spectrometry is illustrated with reference to the biosynthesis of the mycotoxin mycophenolic acid in Penicillium brevicompactum and the mode of action of the anticholesterolemic drug 20,25-diazacholesterol. Both examples used 1-[ 14 C]acetate precursors. It is shown that the increased sensitivity and specificity of the selected ion monitoring mode detector permits straightforward detection and identification of the relatively small cellular pools associated with metabolic intermediates. The computer program RADSIM is described. Problems that still exist in using radiogas gas chromatography mass spectrometry technology to analyse isotope incorporation experiments are discussed. (author)

Production des micro-algues des claires ostréicoles en relation avec l'azote organique dissous excrété par les huîtres

OpenAIRE

Robert, Jean-michel; Maestrini, Serge; Heral, Maurice; Zanette, Yvan

1981-01-01

L'utilisation de tests biologiques dans l'étude de la fertilité des eaux de claires ainsi que l'analyse chimique des réserves en sels nutritifs des mêmes eaux montrent qu'une part importante de la biomasse micro-algale peut être produite dans ces bassins, par assimilation par les cellules de substances organiques dissoutes. Ainsi, pour l'azote, des estimations indirectes aboutissent à des quantités de cet élément assimilé sous forme organique variant entre 0,6 et 30,7 µg-at.I-1 selon les mode...

Intoxication par la paraphényléne-diamine

African Journals Online (AJOL)

raoul

9 mars 2011 ... remède contre la douleur par Averbukh [8], ou contre la constipation par Schemesh [9], mais l´utilisation à des fins autolytique reste toujours prédominante. Le tableau clinique de l´intoxication à ... une anurie ayant nécessité le recours à l´hémodialyse. Ce taux de survenue d´IRA anurique est relativement ...

Optical spectroscopy versus mass spectrometry: The race for fieldable isotopic analysis

International Nuclear Information System (INIS)

Barshick, C.M.; Young, J.P.; Shaw, R.W.

1995-01-01

Several techniques have been developed to provide on-site isotopic analyses, including decay-counting and mass spectrometry, as well as methods that rely on the accessibility of optical transitions for isotopic selectivity (e.g., laser-induced fluorescence and optogalvanic spectroscopy). The authors have been investigating both mass spectrometry and optogalvanic spectroscopy for several years. Although others have considered these techniques for isotopic analysis, the authors have focussed on the use of a dc glow discharge for atomization and ionization, and a demountable discharge cell for rapid sample exchange. The authors' goal is a fieldable instrument that provides useful uranium isotope ratio information

Identifying modifications in RNA by MALDI mass spectrometry

DEFF Research Database (Denmark)

Douthwaite, Stephen; Kirpekar, Finn

2007-01-01

as RNA modifications added in cell-free in vitro systems. MALDI-MS is particularly useful in cases in which other techniques such as those involving primer extension or chromatographic analyses are not practicable. To date, MALDI-MS has been used to localize rRNA modifications that are involved......Posttranscriptional modifications on the base or sugar of ribonucleosides generally result in mass increases that can be measured by mass spectrometry. Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a direct and accurate means of determining the masses of RNAs. Mass...... spectra produced by MALDI are relatively straightforward to interpret, because they are dominated by singly charged ions, making it possible to analyze complex mixtures of RNA oligonucleotides ranging from trinucleotides up to 20-mers. Analysis of modifications within much longer RNAs, such as ribosomal...

MSiReader v1.0: Evolving Open-Source Mass Spectrometry Imaging Software for Targeted and Untargeted Analyses

Science.gov (United States)

Bokhart, Mark T.; Nazari, Milad; Garrard, Kenneth P.; Muddiman, David C.

2018-01-01

A major update to the mass spectrometry imaging (MSI) software MSiReader is presented, offering a multitude of newly added features critical to MSI analyses. MSiReader is a free, open-source, and vendor-neutral software written in the MATLAB platform and is capable of analyzing most common MSI data formats. A standalone version of the software, which does not require a MATLAB license, is also distributed. The newly incorporated data analysis features expand the utility of MSiReader beyond simple visualization of molecular distributions. The MSiQuantification tool allows researchers to calculate absolute concentrations from quantification MSI experiments exclusively through MSiReader software, significantly reducing data analysis time. An image overlay feature allows the incorporation of complementary imaging modalities to be displayed with the MSI data. A polarity filter has also been incorporated into the data loading step, allowing the facile analysis of polarity switching experiments without the need for data parsing prior to loading the data file into MSiReader. A quality assurance feature to generate a mass measurement accuracy (MMA) heatmap for an analyte of interest has also been added to allow for the investigation of MMA across the imaging experiment. Most importantly, as new features have been added performance has not degraded, in fact it has been dramatically improved. These new tools and the improvements to the performance in MSiReader v1.0 enable the MSI community to evaluate their data in greater depth and in less time. [Figure not available: see fulltext.

Review of application of mass spectrometry for analyses of anterior eye proteome

Institute of Scientific and Technical Information of China (English)

Sherif; Elsobky; Ashley; M; Crane; Michael; Margolis; Teresia; A; Carreon; Sanjoy; K; Bhattacharya

2014-01-01

Proteins have important functional roles in the body, which can be altered in disease states. The eye is a complex organ rich in proteins; in particular, the anterior eye is very sophisticated in function and is most commonly involved in ophthalmic diseases. Proteomics, the large scale study of proteins, has greatly impacted our knowledge and understanding of gene function in the post-genomic period. The most significant breakthrough in proteomics has been mass spectrometric identification of proteins, which extends analysis far beyond the mere display of proteins that classical techniques provide. Mass spectrometry functions as a "mass analyzer" which simplifies the identification and quantification of proteins extracted from biological tissue. Mass spectrometric analysis of the anterior eye proteome provides a differential display for protein comparison of normal and diseased tissue. In this article wepresent the key proteomic findings in the recent literature related to the cornea, aqueous humor, trabecular meshwork, iris, ciliary body and lens. Through this we identified unique proteins specific to diseases related to the anterior eye.

Profiling gene expression induced by protease-activated receptor 2 (PAR2 activation in human kidney cells.

Directory of Open Access Journals (Sweden)

Jacky Y Suen

Full Text Available Protease-Activated Receptor-2 (PAR2 has been implicated through genetic knockout mice with cytokine regulation and arthritis development. Many studies have associated PAR2 with inflammatory conditions (arthritis, airways inflammation, IBD and key events in tumor progression (angiogenesis, metastasis, but they have relied heavily on the use of single agonists to identify physiological roles for PAR2. However such probes are now known not to be highly selective for PAR2, and thus precisely what PAR2 does and what mechanisms of downstream regulation are truly affected remain obscure. Effects of PAR2 activation on gene expression in Human Embryonic Kidney cells (HEK293, a commonly studied cell line in PAR2 research, were investigated here by comparing 19,000 human genes for intersecting up- or down-regulation by both trypsin (an endogenous protease that activates PAR2 and a PAR2 activating hexapeptide (2f-LIGRLO-NH(2. Among 2,500 human genes regulated similarly by both agonists, there were clear associations between PAR2 activation and cellular metabolism (1,000 genes, the cell cycle, the MAPK pathway, HDAC and sirtuin enzymes, inflammatory cytokines, and anti-complement function. PAR-2 activation up-regulated four genes more than 5 fold (DUSP6, WWOX, AREG, SERPINB2 and down-regulated another six genes more than 3 fold (TXNIP, RARG, ITGB4, CTSD, MSC and TM4SF15. Both PAR2 and PAR1 activation resulted in up-regulated expression of several genes (CD44, FOSL1, TNFRSF12A, RAB3A, COPEB, CORO1C, THBS1, SDC4 known to be important in cancer. This is the first widespread profiling of specific activation of PAR2 and provides a valuable platform for better understanding key mechanistic roles of PAR2 in human physiology. Results clearly support the development of both antagonists and agonists of human PAR2 as potential disease modifying therapeutic agents.

par genes in Mycobacterium bovis and Mycobacterium smegmatis are arranged in an operon transcribed from "SigGC" promoters

Directory of Open Access Journals (Sweden)

Casart Yveth

2008-03-01

Full Text Available Abstract Background The ParA/Soj and ParB/Spo0J proteins, and the cis-acting parS site, participate actively in chromosome segregation and cell cycle progression. Genes homologous to parA and parB, and two putative parS copies, have been identified in the Mycobacterium bovis BCG and Mycobacterium smegmatis chromosomes. As in Mycobacterium tuberculosis, the parA and parB genes in these two non-pathogenic mycobacteria are located near the chromosomal origin of replication. The present work focused on the determination of the transcriptional organisation of the ~6 Kb orf60K-parB region of M. bovis BCG and M. smegmatis by primer extension, transcriptional fusions to the green fluorescence protein (GFP and quantitative RT-PCR. Results The parAB genes were arranged in an operon. However, we also found promoters upstream of each one of these genes. Seven putative promoter sequences were identified in the orf60K-parB region of M. bovis BCG, whilst four were identified in the homologous region of M. smegmatis, one upstream of each open reading frame (ORF. Real-time PCR assays showed that in M. smegmatis, mRNA-parA and mRNA-parB levels decreased between the exponential and stationary phases. In M. bovis BCG, mRNA-parA levels also decreased between the exponential and stationary phases. However, parB expression was higher than parA expression and remained almost unchanged along the growth curve. Conclusion The majority of the proposed promoter regions had features characteristic of Mycobacterium promoters previously denoted as Group D. The -10 hexamer of a strong E. coli σ70-like promoter, located upstream of gidB of M. bovis BCG, overlapped with a putative parS sequence, suggesting that the transcription from this promoter might be regulated by the binding of ParB to parS.

Analyses des taxes et de la pauvreté pour faire avancer la lutte ...

International Development Research Centre (IDRC) Digital Library (Canada)

Analyses des taxes et de la pauvreté pour faire avancer la lutte contre le tabagisme à l'échelle mondiale. Ce projet, mis en place par l'Instituto Nacional de Salud Pública du Mexique, consiste à entreprendre une série d'études préliminaires pour contribuer aux travaux de la nouvelle commission sur la lutte antitabac à ...

Par-4-mediated recruitment of Amida to the actin cytoskeleton leads to the induction of apoptosis

International Nuclear Information System (INIS)

Boosen, Meike; Vetterkind, Susanne; Koplin, Ansgar; Illenberger, Susanne; Preuss, Ute

2005-01-01

Par-4 (prostate apoptosis response-4) sensitizes cells to apoptotic stimuli, but the exact mechanisms are still poorly understood. Using Par-4 as bait in a yeast two-hybrid screen, we identified Amida as a novel interaction partner, a ubiquitously expressed protein which has been suggested to be involved in apoptotic processes. Complex formation of Par-4 and Amida occurs in vitro and in vivo and is mediated via the C-termini of both proteins, involving the leucine zipper of Par-4. Amida resides mainly in the nucleus but displays nucleo-cytoplasmic shuttling in heterokaryons. Upon coexpression with Par-4 in REF52.2 cells, Amida translocates to the cytoplasm and is recruited to actin filaments by Par-4, resulting in enhanced induction of apoptosis. The synergistic effect of Amida/Par-4 complexes on the induction of apoptosis is abrogated when either Amida/Par-4 complex formation or association of these complexes with the actin cytoskeleton is impaired, indicating that the Par-4-mediated relocation of Amida to the actin cytoskeleton is crucial for the pro-apoptotic function of Par-4/Amida complexes in REF52.2 cells. The latter results in enhanced phosphorylation of the regulatory light chain of myosin II (MLC) as has previously been shown for Par-4-mediated recruitment of DAP-like kinase (Dlk), suggesting that the recruitment of nuclear proteins involved in the regulation of apoptotic processes to the actin filament system by Par-4 represents a potent mechanism how Par-4 can trigger apoptosis

AMS analyses at ANSTO

Energy Technology Data Exchange (ETDEWEB)

Lawson, E.M. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia). Physics Division

1998-03-01

The major use of ANTARES is Accelerator Mass Spectrometry (AMS) with {sup 14}C being the most commonly analysed radioisotope - presently about 35 % of the available beam time on ANTARES is used for {sup 14}C measurements. The accelerator measurements are supported by, and dependent on, a strong sample preparation section. The ANTARES AMS facility supports a wide range of investigations into fields such as global climate change, ice cores, oceanography, dendrochronology, anthropology, and classical and Australian archaeology. Described here are some examples of the ways in which AMS has been applied to support research into the archaeology, prehistory and culture of this continent`s indigenous Aboriginal peoples. (author)

AMS analyses at ANSTO

International Nuclear Information System (INIS)

Lawson, E.M.

1998-01-01

The major use of ANTARES is Accelerator Mass Spectrometry (AMS) with 14 C being the most commonly analysed radioisotope - presently about 35 % of the available beam time on ANTARES is used for 14 C measurements. The accelerator measurements are supported by, and dependent on, a strong sample preparation section. The ANTARES AMS facility supports a wide range of investigations into fields such as global climate change, ice cores, oceanography, dendrochronology, anthropology, and classical and Australian archaeology. Described here are some examples of the ways in which AMS has been applied to support research into the archaeology, prehistory and culture of this continent's indigenous Aboriginal peoples. (author)

Cadmium, copper, lead, and zinc determination in precipitation: A comparison of inductively coupled plasma atomic emission spectrometry and graphite furnace atomization atomic absorption spectrometry

Science.gov (United States)

Reddy, M.M.; Benefiel, M.A.; Claassen, H.C.

1987-01-01

Selected trace element analysis for cadmium, copper, lead, and zinc in precipitation samples by inductively coupled plasma atomic emission Spectrometry (ICP) and by atomic absorption spectrometry with graphite furnace atomization (AAGF) have been evaluated. This task was conducted in conjunction with a longterm study of precipitation chemistry at high altitude sites located in remote areas of the southwestern United States. Coefficients of variation and recovery values were determined for a standard reference water sample for all metals examined for both techniques. At concentration levels less than 10 micrograms per liter AAGF analyses exhibited better precision and accuracy than ICP. Both methods appear to offer the potential for cost-effective analysis of trace metal ions in precipitation. ?? 1987 Springer-Verlag.

Reactor gamma spectrometry: status

International Nuclear Information System (INIS)

Gold, R.; Kaiser, B.J.

1979-01-01

Current work is described for Compton Recoil Gamma-Ray Spectrometry including developments in experimental technique as well as recent reactor spectrometry measurements. The current status of the method is described concerning gamma spectromoetry probe design and response characteristics. Emphasis is given to gamma spectrometry work in US LWR and BR programs. Gamma spectrometry in BR environments are outlined by focussing on start-up plans for the Fast Test Reactor (FTR). Gamma spectrometry results are presented for a LWR pressure vessel mockup in the Poolside Critical Assembly (PCA) at Oak Ridge National Laboratory

Prognostic value of suPAR and hs-CRP on cardiovascular disease

DEFF Research Database (Denmark)

Diederichsen, Marie Zöga; Diederichsen, Søren Zöga; Mickley, Hans

2018-01-01

Background and aims: Studies have shown that soluble urokinase Plasminogen Activator Receptor (suPAR) and CRP (both inflammatory markers) and coronary artery calcification (CAC) are independent risk predictors for cardiovascular (CV) disease. The aim of this study is to assess whether suPAR and CRP...... have an increased predictive prognostic value beyond the traditional CV risk factors and the CAC score. Methods: A population sample of 1179 subjects, free of CV disease was included. The subjects underwent traditional CV risk evaluation, CAC assessment and blood sampling for suPAR and CRP. CV events...

Broca Pars Triangularis Constitutes a “Hub” of the Language-Control Network during Simultaneous Language Translation

Directory of Open Access Journals (Sweden)

Stefan Elmer

2016-09-01

Full Text Available Until now, several branches of research have fundamentally contributed to a better understanding of the ramifications of bilingualism, multilingualism, and language expertise on psycholinguistic-, cognitive-, and neural implications. In this context, it is noteworthy to mention that from a cognitive perspective, there is a strong convergence of data pointing to an influence of multilingual speech competence on a variety of cognitive functions, including attention, short-term- and working memory, set shifting, switching, and inhibition. In addition, complementary neuroimaging findings have highlighted a specific set of cortical and subcortical brain regions which fundamentally contribute to administrate cognitive control in the multilingual brain, namely Broca’s area, the middle-anterior cingulate cortex, the inferior parietal lobe, and the basal ganglia. However, a disadvantage of focusing on group analyses is that this procedure only enables an approximation of the neural networks shared within a population while at the same time smoothing inter-individual differences. In order to address both commonalities (i.e., within group analyses and inter-individual variability (i.e., single-subject analyses in language control mechanisms, here I measured five professional simultaneous interpreters while the participants overtly translated or repeated sentences with a simple subject-verb-object structure. Results demonstrated that pars triangularis was commonly activated across participants during backward translation (i.e., from L2 to L1, whereas the other brain regions of the control network showed a strong inter-individual variability during both backward and forward (i.e., from L1 to L2 translation. Thus, I propose that pars triangularis plays a crucial role within the language-control network and behaves as a fundamental processing entity supporting simultaneous language translation.

mTORC2 activation is regulated by the urokinase receptor (uPAR) in bladder cancer.

Science.gov (United States)

Hau, Andrew M; Leivo, Mariah Z; Gilder, Andrew S; Hu, Jing-Jing; Gonias, Steven L; Hansel, Donna E

2017-01-01

Mammalian target of rapamycin complex 2 (mTORC2) has been identified as a major regulator of bladder cancer cell migration and invasion. Upstream pathways that mediate mTORC2 activation remain poorly defined. Urokinase-type plasminogen activator receptor (uPAR) is a GPI-anchored membrane protein and known activator of cell-signaling. We identified increased uPAR expression in 94% of invasive human bladder cancers and in 54-71% of non-invasive bladder cancers, depending on grade. Normal urothelium was uPAR-immunonegative. Analysis of publicly available datasets identified uPAR gene amplification or mRNA upregulation in a subset of bladder cancer patients with reduced overall survival. Using biochemical approaches, we showed that uPAR activates mTORC2 in bladder cancer cells. Highly invasive bladder cancer cell lines, including T24, J82 and UM-UC-3 cells, showed increased uPAR mRNA expression and protein levels compared with the less aggressive cell lines, UROtsa and RT4. uPAR gene-silencing significantly reduced phosphorylation of Serine-473 in Akt, an mTORC2 target. uPAR gene-silencing also reduced bladder cancer cell migration and Matrigel invasion. S473 phosphorylation was observed by immunohistochemistry in human bladder cancers only when the tumors expressed high levels of uPAR. S473 phosphorylation was not controlled by uPAR in bladder cancer cell lines that are PTEN-negative; however, this result probably did not reflect altered mTORC2 regulation. Instead, PTEN deficiency de-repressed alternative kinases that phosphorylate S473. Our results suggest that uPAR and mTORC2 are components of a single cell-signaling pathway. Targeting uPAR or mTORC2 may be beneficial in patients with bladder cancer. Copyright © 2016. Published by Elsevier Inc.

Mass and emission spectrometry in the Analytical Chemistry Division of Oak Ridge National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Smith, D.H. (ed.)

1978-11-01

The capabilities of the Mass and Emission Spectrometry Section of the Analytical Chemistry Division of Oak Ridge National Laboratory are described. Many different areas of mass spectrometric expertise are represented in the section: gas analysis, high abundance sensitivity measurements, high- and low-resolution organic analyses, spark source trace constituent analysis, and ion microprobe analysis of surfaces. These capabilities are complemented by emission spectrometry. The instruments are described along with a few applications, some of which are unique.

Mass and emission spectrometry in the Analytical Chemistry Division of Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Smith, D.H.

1978-11-01

The capabilities of the Mass and Emission Spectrometry Section of the Analytical Chemistry Division of Oak Ridge National Laboratory are described. Many different areas of mass spectrometric expertise are represented in the section: gas analysis, high abundance sensitivity measurements, high- and low-resolution organic analyses, spark source trace constituent analysis, and ion microprobe analysis of surfaces. These capabilities are complemented by emission spectrometry. The instruments are described along with a few applications, some of which are unique

Réduction du risque d'infection par le VIH au Botswana - essais ...

International Development Research Centre (IDRC) Digital Library (Canada)

Au Botswana, ce sont les jeunes femmes qui sont le plus touchées par les nouvelles infections par le VIH. Le présent projet a pour but de réduire le nombre de nouveaux cas d'infection par le VIH, en particulier chez les femmes de 15 à 29 ans. Bien que l'on recense des cas de VIH/sida dans la plupart des régions du ...

New developments in the analysis and measurement of thicknesses by excitation of the fluorescent lines by means of {beta} particles; Nouveaux developpements de l'analyse et de la mesure des epaisseurs par excitation des raies de fluorescence au moyen de particules {beta}

Energy Technology Data Exchange (ETDEWEB)

Martinelli, P [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Seibel, G [Institut de Recherches de la Siderurgie, 78 - Saint-Germain-en-Laye (France)

1960-07-01

The process for analysing and measuring the thickness of deposits by {beta}-X fluorescence which we have already described has undergone further development. The use of promethium-147 and krypton-85 sources makes it possible to reduce the background noise which is observed with strontium-90. We present the results obtained for various measurements of the thickness of metallic coatings and the continuous measurement of calcium and of iron in ore samples. We describe the tests carried out with a view to analysing the X-rays by means of a crystal. (author) [French] Le procede d'analyse et de mesure des epaisseurs de depots par fluorescence {beta}-X que nous avons precedemment decrit a fait l'objet de nouveaux developpements. L'emploi de sources de prometheum-147 et de krypton-85 permet de reduire le bruit de fond que l'on observe avec le strontium-90. Nous dormons les resultats obtenus pour diverses mesures d'epaisseurs de depots metalliques et la mesure en continu du calcium et du fer dans les carottes de minerais. Nous decrivons les essais effectues en vue d'analyser le rayonnement X au moyen d'un cristal. (auteur)

La magie de Saint-Cloud par Mme d’Aulnoy

Directory of Open Access Journals (Sweden)

Sophie Raynard

2010-12-01

Full Text Available Cet article se propose d’analyser la manière dont Mme d’Aulnoy a su préparer ses lecteurs au « merveilleux » de ses contes en les encadrant dans un récit prenant place dans le domaine royal de Saint‐Cloud. Par le moyen d’images textuelles particulières comme la mise en abyme et l’ekphrasis, et jouant sur la réputation enchanteresse de Saint‐Cloud, la conteuse a elle aussi participé à la création de la magie de Saint‐Cloud au même titre que les artistes et artisans qui ont accompli ce chef‐d’oeuvre architectural, pictural et esthétique. C’est ce que nous verrons en mettant en parallèle les textes de fiction et de non‐fiction qui décrivent Saint‐Cloud à l’époque de son apogée.

The role of CFD computer analyses in hydrogen safety management

International Nuclear Information System (INIS)

Komen, E.M.J; Visser, D.C; Roelofs, F.; Te Lintelo, J.G.T

2014-01-01

The risks of hydrogen release and combustion during a severe accident in a light water reactor have attracted considerable attention after the Fukushima accident in Japan. Reliable computer analyses are needed for the optimal design of hydrogen mitigation systems, like e.g. passive autocatalytic recombiners (PARs), and for the assessment of the associated residual risk of hydrogen combustion. Traditionally, so-called Lumped Parameter (LP) computer codes are being used for these purposes. In the last decade, significant progress has been made in the development, validation, and application of more detailed, three-dimensional Computational Fluid Dynamics (CFD) simulations for hydrogen safety analyses. The objective of the current paper is to address the following questions: - When are CFD computer analyses needed complementary to the traditional LP code analyses for hydrogen safety management? - What is the validation status of the CFD computer code for hydrogen distribution, mitigation, and combustion analyses? - Can CFD computer analyses nowadays be executed in practical and reliable way for full scale containments? The validation status and reliability of CFD code simulations will be illustrated by validation analyses performed for experiments executed in the PANDA, THAI, and ENACCEF facilities. (authors)

Évaluation spatiale et prospectives sur le risque de pollution diffuse par le nitrate sur le bassin versant de la Bultière

Directory of Open Access Journals (Sweden)

LE FLAHEC, François

2015-06-01

Full Text Available En France, la protection des captages d'eau potable est une préoccupation majeure : le Grenelle Environnement a identifié plus de cinq cents sites menacés par les pollutions diffuses, d'où la nécessité de mettre en place des plans d'action pour les protéger. En Vendée, dans le bassin versant de la Bultière, confronté à des rejets importants de nitrate, une étude par modélisation agronomique et hydrologique a été mise en œuvre avec le logiciel Swat, un outil alliant analyse spatiale et simulation, qui doit permettre de donner des orientations et de prioriser des solutions.

The joined use of n.i. spectroscopic analyses - FTIR, Raman, visible reflectance spectrometry and EDXRF - to study drawings and illuminated manuscripts

International Nuclear Information System (INIS)

Bruni, S.; Guglielmi, V.; Caglio, S.; Poldi, G.

2008-01-01

Some art objects being small and very precious prevents conservators and conservation scientists from whatever kind of sampling, so that only completely non-invasive (n.i.) studies are permitted. Besides, also moving the object is sometimes forbidden: this happens for jewels as well as for manuscripts, illuminated codices, drawings and paintings. Some important physical n.i. analyses, such as PIXE and PIGE, therefore cannot be used in many cases. With these limitations, only imaging techniques in X, UV, Visible and IR bands, and a few spectroscopic methods that can be carried out with portable instruments can be applied, i.e. molecular spectroscopies like Fourier transform infrared (FTIR), Raman, UV visible and near IR reflectance spectrometry (UV-Vis-NIR RS) and atomic spectroscopy like energy dispersive X-ray fluorescence (EDXRF). The use of only one or two of these techniques is usually far from giving all the information required to achieve a full characterization of materials used by the artist or during restorations, and to understand some conservative problems of the object. On the contrary, a joined use of n.i. analyses can supply a larger set of data, allowing for cross checks. With this aim we show a fully integrated spectroscopic approach to polychrome objects, and, in particular, to drawings and illuminated manuscripts, using portable instruments, specifically μ-FTIR, μ-Raman, Vis-RS and EDXRF, where also the Raman signal does not suffer fluorescence caused by varnish coating and from binder. We propose the joined use of all these four physical analyses to characterize materials - support, pigments, dyes, binders, etc. - on a complex case: a painted and drawn parchment of the late 15th century, or the beginning of the 16th, partly attributed to Andrea Mantegna. The collected spectroscopic data have been compared to proper spectral databases, some of which specifically realized in our laboratories. Also, mixtures of pigments and their stratigraphical

Alpha spectrometry and secondary ion mass spectrometry of thorium

International Nuclear Information System (INIS)

Strisovska, Jana; Kuruc, Jozef; Galanda, Dusan; Matel, Lubomir; Velic, Dusan; Aranyosiova, Monika

2009-01-01

A sample of thorium content on steel discs was prepared by electrodeposition with a view to determining the natural thorium isotope. Thorium was determined by alpha spectrometry and by secondary ion mass spectrometry and the results of the two methods were compared

A mechanism for ParB-dependent waves of ParA, a protein related to DNA segregation during cell division in prokaryotes

DEFF Research Database (Denmark)

Hunding, Axel; Gerdes, Kenn; Charbon, Gitte Ebersbach

2003-01-01

in an autocatalytic process. We discuss this mechanism in relation to recent models for MinDE oscillations in E.coli and to microtubule degradation in mitosis. The study points to an ancestral role for the presented pattern types in generating bipolarity in prokaryotes and eukaryotes.......Prokaryotic plasmids encode partitioning (par) loci involved in segregation of DNA to daughter cells at cell division. A functional fusion protein consisting of Walker-type ParA ATPase and green fluorescent protein (Gfp) oscillates back and forth within nucleoid regions with a wave period of about...

Application of energy dispersive XRF-spectrometry to analyse nutritional elements in relation to cancer

International Nuclear Information System (INIS)

Hota, P.K.; Vijayan, V.; Singh, L.P.

2001-01-01

Food is the principal media for intake of elements from environment to human body. Thus, it is felt important to determine the daily dietary intake of such elements in the field of toxicity and nutrition, the deficiency or sufficiency of which may lead to various diseases, disorders and allergies in human health. In this study, the elements present in commonly used cereals, pulses, noodles, some condiments/spices, tobacco products, some common leaves used in herbal medicine and tea leaves have been analyzed using EDXRF spectrometry technique. Elemental concentrations of K, Ca, Fe, Sr, Mn, Zn, Cu, Pb, As and Se are detected and quantified in all the samples using this method. The results are discussed in relation to cancer. (author)

Accelerator-based ultrasensitive mass spectrometry

International Nuclear Information System (INIS)

Gove, H.E.

1985-01-01

This chapter describes a new mass spectrometry technique involving charged particle accelerators normally used for basic research in nuclear science. Topics considered include the limitations of conventional mass spectrometry, the limitations of the direct measurement of radioactive decay, mass spectrometry using a tandem electrostatic accelerator, mass spectrometry using a cyclotron, how accelerator mass spectrometry circumvents the limitations of conventional mass spectrometry, measurements of stable isotopes, nuclear physics and astrophysics applications, modifications to existing accelerators, descriptions of dedicated systems, and future applications

Evaluation of metal and radionuclide data from neutron activation and acid-digestion-based spectrometry analyses of background soils. Significance in environmental restoration

International Nuclear Information System (INIS)

Lee, S.Y.; Watkins, D.R.; Jackson, B.L.; Schmoyer, R.L.; Lietzke, D.A.; Burgoa, B.B.; Branson, J.T.; Ammons, J.T.

1997-01-01

A faster, more cost-effective, and higher-quality data acquisition for natural background-level metals and radionuclides in soils is needed for remedial investigations of contaminated sites. The advantages and disadvantages of neutron activation analysis (NAA) compared with those of acid-digestion-based spectrometry (ADS) methods were evaluated using Al, Sb, As, Cr, Co, Fe, Mg, Mn, Hg, K, Ag, 232 Th, 235 U, 238 U, V, and Zn data. The ADS methods used for this project were inductively coupled plasma (ICP), ICP-mass spectrometry (ICP-MS), and alpha spectrometry. Scatter plots showed that the NAA results for As, Co, Fe, Mn, 232 Th, and 238 U are reasonably correlated with the results from the other analytical methods. Compared to NAA, however, the ADS methods underestimated Al, Cr, Mg, K, V, and Zn. Because of the high detection limits of ADS methods, the scatter plots of Sb, Hg, and Ag did not show a definite relationship. The NAA results were highly correlated with the alpha spectrometry results for 232T h and 238 U but poorly correlated for 235 U. The NAA, including the delayed neutron counting, was a far superior technique for quantifying background levels of radionuclides ( 232 Th, 235 U, and 238 U) and metals (Al, Cr, Mg, K, V, and Zn) in soils. (author)

[Ambroise Paré in French literature].

Science.gov (United States)

Dumaitre, P

1995-01-01

The 16th century by its passionate side has been the favourite one of authors of historical novels in which among the heroes of "cloak and dagger stories" appears sometime Ambroise Paré. Alexandre Dumas (the father) has shown him at the court of Charles IX in La Reine Margot (1845) where he does not however play a great role. On the contrary, Balzac in Le Martyr calviniste (1842) has given him a capital part close to the dying François II, whom he intended to trepanize but had to give up this idea as a consequence of the opposition of the queen-mother Catherine de Médicis. In the present century, Robert Merle in Paris ma bonne ville (Fortune de France, 3, 1980) shows Paré at the time of the Saint Barthélemy.

Les dispensées par fantaisie en éducation physique et sportive ...

African Journals Online (AJOL)

Cette étude vise à comprendre les raisons avancées par les élèves dispensés par fantaisie des cours d'EPS, pour justifier leur attitude et principalement leur forfait. Une enquête par questionnaire écrit a été menée dans 13 établissements publics de la ville de Porto-Novo au Bénin. Au total, 203 élèves parmi les 771 élèves ...

Complexation de l'aluminium par des hétéropolyanions lacunaires ...

African Journals Online (AJOL)

L'objectif visé par cette étude est la dépollution des eaux à partir de la complexation d'un métal toxique, l'aluminium en solution, par des hétéropolyanions lacunaires (HPA) de type Dawson. Les complexes formés sont récupérés par membrane liquide émulsionnée (MEL).Les résultats de la complex1ation de l'aluminium ...

Uranium-lead dating method at the Pará-Iso isotope geology laboratory, UFPA, Belém - Brazil

Directory of Open Access Journals (Sweden)

Robert S. Krymsky

2007-03-01

Full Text Available Analytical procedures for U-Pb isotope dilution analyses at the Pará-Iso isotope geology laboratory of the Federal University of Pará (UFPA are described in detail. The procedures are applied to zircon, titanite, rutile, apatite, columbite-tantalite and whole rock. Reagent preparation and chemical processing are done in clean-room conditions. Samples are dissolved using TeflonTM microcapsules in steel jacket TeflonTM Parr InstrumentTM bomb or TeflonTM screw cap containers. U and Pb are separated using anion exchange AG 1x8 resin columns. Typical blanks for mineral sample amounts of 0.01 to 1.0 mg are less than 1 pg U and 20-30 pg Pb. Isotope analysis of the U and Pb from the same filament are carried out using a Finnigan MAT 262 mass-spectrometer in static and dynamic modes. The current analytical level is demonstrated on analyses of international standard zircon 91500 with three different 235U-205Pb and 235U-208Pb isotope tracers and whole rock standards. Results of analyses of two zircon samples are also presented.Os procedimentos analíticos para análises U-Pb por diluição isotópica no Laboratório de Geologia Isotópica (Pará-Iso da Universidade Federal do Pará (UFPA são descritos detalhadamente. Esses procedimentos são aplicados para análises de zircão, titanita, rutilo, apatita, columbita-tantalita e rocha total. A purificação dos reagentes e os procedimentos químicos são feitos em salas limpas. As amostras são dissolvidas em microcápsulas de Teflon em bombas do tipo Parr InstrumentTM. U e Pb são separados em colunas com resina de troca iônica AG 1x8. Os brancos de procedimento para amostra típica(0,01-1 mg são menores que 1 pg de U e 20-30 pg de Pb. As análises isotópicas de Pb e de U são feitas em um único filamento de Re em um espectrômetro de massa Finnigan MAT 262 nos modos estático e dinâmico. O nível analítico atual é comprovado pelas análises do padrão internacional de zircão 91500, usando tr

Determination of mercury in hair: Comparison between gold amalgamation-atomic absorption spectrometry and mass spectrometry.

Science.gov (United States)

Domanico, Francesco; Forte, Giovanni; Majorani, Costanza; Senofonte, Oreste; Petrucci, Francesco; Pezzi, Vincenzo; Alimonti, Alessandro

2017-09-01

Mercury is a heavy metal that causes serious health problems in exposed subjects. The most toxic form, i.e., methylmercury (MeHg), is mostly excreted through human hair. Numerous analytical methods are available for total Hg analysis in human hair, including cold vapour atomic fluorescence spectrometry (CV-AFS), inductively coupled plasma mass spectrometry (ICP-MS) and thermal decomposition amalgamation atomic absorption spectrometry (TDA-AAS). The aim of the study was to compare the TDA-AAS with the ICP-MS in the Hg quantification in human hair. After the washing procedure to minimize the external contamination, from each hair sample two aliquots were taken; the first was used for direct analysis of Hg by TDA-AAS and the second was digested for Hg determination by the ICP-MS. Results indicated that the two data sets were fully comparable (median; TDA-AAS, 475ngg -1 ; ICP-MS, 437ngg -1 ) and were not statistically different (Mann-Whitney test; p=0.44). The two techniques presented results with a good coefficient of correlation (r=0.94) despite different operative ranges and method limits. Both techniques satisfied internal performance requirements and the parameters for method validation resulting sensitive, precise and reliable. Finally, the use of the TDA-AAS can be considered instead of the ICP-MS in hair analysis in order to reduce sample manipulation with minor risk of contamination, less time consuming due to the absence of the digestion step and cheaper analyses. Copyright © 2016 Elsevier GmbH. All rights reserved.

Removal of focal segmental glomerulosclerosis (FSGS) factor suPAR using CytoSorb.

Science.gov (United States)

Schenk, Heiko; Müller-Deile, Janina; Schmitt, Roland; Bräsen, Jan Hinrich; Haller, Hermann; Schiffer, Mario

2017-12-01

Treatment of primary focal segmental glomerulosclerosis (FSGS) and its recurrence after kidney transplantation associated with rapid deterioration of kidney function remains to be challenging despite advances in immunosuppressive therapy. The presence of circulating factors has been postulated to be a pivotal player in the pathogenesis of FSGS, although suPAR and CLCF-1 have been identified as the most promising causative factors. The potential therapeutic effect of suPAR elimination in an FSGS patient using CytoSorb, a hemoadsorption device that gained attention in the cytokine elimination in septic patients, was studied. Efficiency of total plasma exchange to remove suPAR was determined. CytoSorb hemoadsorption caused a 27.33% reduction of the suPAR level in a single treatment, whereas total plasma exchange showed a suPAR level reduction of 25.12% (n = 3; 95% confidence interval, 0.2777-0.8090; P < 0.01), which may indicate therapeutic potential in the treatment of primary FSGS and its recurrence in a kidney transplant. © 2017 Wiley Periodicals, Inc.

Thrombin induces rapid PAR1-mediated non-classical FGF1 release

International Nuclear Information System (INIS)

Duarte, Maria; Kolev, Vihren; Soldi, Raffaella; Kirov, Alexander; Graziani, Irene; Oliveira, Silvia Marta; Kacer, Doreen; Friesel, Robert; Maciag, Thomas; Prudovsky, Igor

2006-01-01

Thrombin induces cell proliferation and migration during vascular injury. We report that thrombin rapidly stimulated expression and release of the pro-angiogenic polypeptide fibroblast growth factor 1 (FGF1). Thrombin failed to induce FGF1 release from protease-activated receptor 1 (PAR1) null fibroblasts, indicating that this effect was dependent on PAR1. Similarly to thrombin, FGF1 expression and release were induced by TRAP, a specific oligopeptide agonist of PAR1. These results identify a novel aspect of the crosstalk between FGF and thrombin signaling pathways which both play important roles in tissue repair and angiogenesis

Elevated soluble urokinase plasminogen activator receptor (suPAR) predicts mortality in Staphylococcus aureus bacteremia

DEFF Research Database (Denmark)

Mölkänen, T; Ruotsalainen, E; Thorball, C W

2011-01-01

The soluble form of urokinase-type plasminogen activator receptor (suPAR) is a new inflammatory marker. High suPAR levels have been shown to associate with mortality in cancer and in chronic infections like HIV and tuberculosis, but reports on the role of suPAR in acute bacteremic infections...... are scarce. To elucidate the role of suPAR in a common bacteremic infection, the serum suPAR levels in 59 patients with Staphylococcus aureus bacteremia (SAB) were measured using the suPARnostic ELISA assay and associations to 1-month mortality and with deep infection focus were analyzed. On day three, after...... the first positive blood culture for S. aureus, suPAR levels were higher in 19 fatalities (median 12.3; range 5.7-64.6 ng/mL) than in 40 survivors (median 8.4; range 3.7-17.6 ng/mL, p = 0.002). This difference persisted for 10 days. The presence of deep infection focus was not associated with elevated su...

The polarity protein Par6 is coupled to the microtubule network during molluscan early embryogenesis

Energy Technology Data Exchange (ETDEWEB)

Homma, Taihei [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Shimizu, Miho [Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Kuroda, Reiko, E-mail: ckuroda@mail.ecc.u-tokyo.ac.jp [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

2011-01-07

Research highlights: {yields} The cDNAs encoding Par6 and aPKC homologues were cloned from the snail Lymnaea stagnalis. {yields} L. stagnalis Par6 directly interacts with tubulin and microtubules and localizes to the microtubule cytoskeleton during the early embryogenesis. {yields} Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of body handedness. -- Abstract: Cell polarity, which directs the orientation of asymmetric cell division and segregation of fate determinants, is a fundamental feature of development and differentiation. Regulators of polarity have been extensively studied, and the critical importance of the Par (partitioning-defective) complex as the polarity machinery is now recognized in a wide range of eukaryotic systems. The Par polarity module is evolutionarily conserved, but its mechanism and cooperating factors vary among different systems. Here we describe the cloning and characterization of a pond snail Lymnaea stagnalis homologue of partitioning-defective 6 (Lspar6). The protein product LsPar6 shows high affinity for microtubules and localizes to the mitotic apparatus during embryonic cell division. In vitro assays revealed direct binding of LsPar6 to tubulin and microtubules, which is the first evidence of the direct interaction between the two proteins. The interaction is mediated by two distinct regions of LsPar6 both located in the N-terminal half. Atypical PKC, a functional partner of Par6, was also found to localize to the mitotic spindle. These results suggest that the L. stagnalis Par complex employs the microtubule network in cell polarity processes during the early embryogenesis. Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of handedness.

The polarity protein Par6 is coupled to the microtubule network during molluscan early embryogenesis

International Nuclear Information System (INIS)

Homma, Taihei; Shimizu, Miho; Kuroda, Reiko

2011-01-01

Research highlights: → The cDNAs encoding Par6 and aPKC homologues were cloned from the snail Lymnaea stagnalis. → L. stagnalis Par6 directly interacts with tubulin and microtubules and localizes to the microtubule cytoskeleton during the early embryogenesis. → Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of body handedness. -- Abstract: Cell polarity, which directs the orientation of asymmetric cell division and segregation of fate determinants, is a fundamental feature of development and differentiation. Regulators of polarity have been extensively studied, and the critical importance of the Par (partitioning-defective) complex as the polarity machinery is now recognized in a wide range of eukaryotic systems. The Par polarity module is evolutionarily conserved, but its mechanism and cooperating factors vary among different systems. Here we describe the cloning and characterization of a pond snail Lymnaea stagnalis homologue of partitioning-defective 6 (Lspar6). The protein product LsPar6 shows high affinity for microtubules and localizes to the mitotic apparatus during embryonic cell division. In vitro assays revealed direct binding of LsPar6 to tubulin and microtubules, which is the first evidence of the direct interaction between the two proteins. The interaction is mediated by two distinct regions of LsPar6 both located in the N-terminal half. Atypical PKC, a functional partner of Par6, was also found to localize to the mitotic spindle. These results suggest that the L. stagnalis Par complex employs the microtubule network in cell polarity processes during the early embryogenesis. Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of handedness.

PECAN: library-free peptide detection for data-independent acquisition tandem mass spectrometry data

Energy Technology Data Exchange (ETDEWEB)

Ting, Ying S.; Egertson, Jarrett D.; Bollinger, James G.; Searle, Brian C.; Payne, Samuel H.; Noble, William Stafford; MacCoss, Michael J.

2017-08-07

Data-independent acquisition (DIA) is an emerging mass spectrometry (MS)-based technique for unbiased and reproducible measurement of protein mixtures. DIA tandem mass spectrometry spectra are often highly multiplexed, containing product ions from multiple cofragmenting precursors. Detecting peptides directly from DIA data is therefore challenging; most DIA data analyses require spectral libraries. Here we present PECECAN (http://pecan.maccosslab.org), a library-free, peptide-centric tool that robustly and accurately detects peptides directly from DIA data. PECECAN reports evidence of detection based on product ion scoring, which enables detection of low-abundance analytes with poor precursor ion signal. We demonstrate the chromatographic peak picking accuracy and peptide detection capability of PECECAN, and we further validate its detection with data-dependent acquisition and targeted analyses. Lastly, we used PECECAN to build a plasma proteome library from DIA data and to query known sequence variants.

Alterations of palm oil (Elaeis guineensis in the continuous industrial par frying of breaded chicken snacks

Directory of Open Access Journals (Sweden)

Débora Rezende Ferreira

2014-03-01

Full Text Available The physical and chemical alterations in palm oil during continuous industrial par frying of breaded chicken snacks were evaluated using a pseudo first-order kinetic model. The acidity index, refractive index, concentration of polar compounds, viscosity, color, and absorbance (232 and 268 nm of 238 samples of the frying oil collected during 26 days of production were analyzed. For all of the analyses, the results of the oil were below the limits recommended for oil disposal, indicating that the processing conditions were safe and that under these experimental conditions the oil remained suitable for frying. The linear regressions were significant for refractive index, content of polar compounds, and lightness (L*. The content of polar compounds was determined using a cooking oil tester, and it had the best fit to the proposed model and can be used as an effective index for monitoring palm oil during the continuous par frying of breaded chicken snacks. The high turnover rate of the oil was important for maintaining the oil in good running conditions.

MARK/Par1 Kinase Is Activated Downstream of NMDA Receptors through a PKA-Dependent Mechanism.

Directory of Open Access Journals (Sweden)

Laura P Bernard

Full Text Available The Par1 kinases, also known as microtubule affinity-regulating kinases (MARKs, are important for the establishment of cell polarity from worms to mammals. Dysregulation of these kinases has been implicated in autism, Alzheimer's disease and cancer. Despite their important function in health and disease, it has been unclear how the activity of MARK/Par1 is regulated by signals from cell surface receptors. Here we show that MARK/Par1 is activated downstream of NMDA receptors in primary hippocampal neurons. Further, we show that this activation is dependent on protein kinase A (PKA, through the phosphorylation of Ser431 of Par4/LKB1, the major upstream kinase of MARK/Par1. Together, our data reveal a novel mechanism by which MARK/Par1 is activated at the neuronal synapse.

Tumour Microenvironments Induce Expression of Urokinase Plasminogen Activator Receptor (uPAR) and Concomitant Activation of Gelatinolytic Enzymes

Science.gov (United States)

Magnussen, Synnøve; Hadler-Olsen, Elin; Latysheva, Nadezhda; Pirila, Emma; Steigen, Sonja E.; Hanes, Robert; Salo, Tuula; Winberg, Jan-Olof; Uhlin-Hansen, Lars; Svineng, Gunbjørg

2014-01-01

Background The urokinase plasminogen activator receptor (uPAR) is associated with poor prognosis in oral squamous cell carcinoma (OSCC), and increased expression of uPAR is often found at the invasive tumour front. The aim of the current study was to elucidate the role of uPAR in invasion and metastasis of OSCC, and the effects of various tumour microenvironments in these processes. Furthermore, we wanted to study whether the cells’ expression level of uPAR affected the activity of gelatinolytic enzymes. Methods The Plaur gene was both overexpressed and knocked-down in the murine OSCC cell line AT84. Tongue and skin tumours were established in syngeneic mice, and cells were also studied in an ex vivo leiomyoma invasion model. Soluble factors derived from leiomyoma tissue, as well as purified extracellular matrix (ECM) proteins, were assessed for their ability to affect uPAR expression, glycosylation and cleavage. Activity of gelatinolytic enzymes in the tissues were assessed by in situ zymography. Results We found that increased levels of uPAR did not induce tumour invasion or metastasis. However, cells expressing low endogenous levels of uPAR in vitro up-regulated uPAR expression both in tongue, skin and leiomyoma tissue. Various ECM proteins had no effect on uPAR expression, while soluble factors originating from the leiomyoma tissue increased both the expression and glycosylation of uPAR, and possibly also affected the proteolytic processing of uPAR. Tumours with high levels of uPAR, as well as cells invading leiomyoma tissue with up-regulated uPAR expression, all displayed enhanced activity of gelatinolytic enzymes. Conclusions Although high levels of uPAR are not sufficient to induce invasion and metastasis, the activity of gelatinolytic enzymes was increased. Furthermore, several tumour microenvironments have the capacity to induce up-regulation of uPAR expression, and soluble factors in the tumour microenvironment may have an important role in the

Tumour microenvironments induce expression of urokinase plasminogen activator receptor (uPAR and concomitant activation of gelatinolytic enzymes.

Directory of Open Access Journals (Sweden)

Synnøve Magnussen

Full Text Available The urokinase plasminogen activator receptor (uPAR is associated with poor prognosis in oral squamous cell carcinoma (OSCC, and increased expression of uPAR is often found at the invasive tumour front. The aim of the current study was to elucidate the role of uPAR in invasion and metastasis of OSCC, and the effects of various tumour microenvironments in these processes. Furthermore, we wanted to study whether the cells' expression level of uPAR affected the activity of gelatinolytic enzymes.The Plaur gene was both overexpressed and knocked-down in the murine OSCC cell line AT84. Tongue and skin tumours were established in syngeneic mice, and cells were also studied in an ex vivo leiomyoma invasion model. Soluble factors derived from leiomyoma tissue, as well as purified extracellular matrix (ECM proteins, were assessed for their ability to affect uPAR expression, glycosylation and cleavage. Activity of gelatinolytic enzymes in the tissues were assessed by in situ zymography.We found that increased levels of uPAR did not induce tumour invasion or metastasis. However, cells expressing low endogenous levels of uPAR in vitro up-regulated uPAR expression both in tongue, skin and leiomyoma tissue. Various ECM proteins had no effect on uPAR expression, while soluble factors originating from the leiomyoma tissue increased both the expression and glycosylation of uPAR, and possibly also affected the proteolytic processing of uPAR. Tumours with high levels of uPAR, as well as cells invading leiomyoma tissue with up-regulated uPAR expression, all displayed enhanced activity of gelatinolytic enzymes.Although high levels of uPAR are not sufficient to induce invasion and metastasis, the activity of gelatinolytic enzymes was increased. Furthermore, several tumour microenvironments have the capacity to induce up-regulation of uPAR expression, and soluble factors in the tumour microenvironment may have an important role in the regulation of posttranslational

Correcting the effects of the matrix using capture gamma-ray spectrometry: Application to measurement by Active Neutron Interrogation; Correction des effets de matrice par spectrometrie des rayonnements gamma de capture: Application a la mesure par Interrogation Neutronique Active (I.N.A.)

Energy Technology Data Exchange (ETDEWEB)

Baudry, G.

2003-11-15

In the field of the measurement of low masses of fissile material ({sup 235}U, {sup 239}Pu, {sup 241}Pu) in radioactive waste drums, the Active Neutron Interrogation is a non-destructive method achieving good results. It does however remain reliant upon uncertainties related to the matrix effects on interrogation and fission neutrons. The aim of this thesis is to develop a correction method able to take into account these matrix effects by quantifying the amount of absorbent materials (chlorine and hydrogen) in a 118- liter homogeneous matrix. The main idea is to use the gamma-ray spectrometry of gamma emitted by neutron captures to identify and quantify the composition of the matrix. An indicator from its chlorine content is then deduced in order to choose the calibration coefficient which best represents the real composition of the matrix. This document firstly presents the needs of control and characterization of radioactive objects, and the means used in the field of nuclear measurement. Emphases is put in particular on the Active Neutron Interrogation method. The matrices of interest are those made of light technological waste (density {<=} 0,4 g/cm{sup 3}) containing hydrogenated and chlorinated materials. The advantages of gamma-rays emitted by neutron captures for the determination of a chlorine content indicator of the matrices and the principles of the correction method are then explained. Measurements have been firstly realized with an existing Neutron Interrogation device (PROMETHEE 6). Such measurements have proven its inadequacy: no signal from the matrix hydrogen was detected, due to an intense signal from the polyethylene contained in some cell elements. Moreover, the matrix chlorine content appeared difficult to be measured. A new and specific device, named REGAIN and dedicated to active gamma-rays spectrometry, was defined with the Monte-Carlo N-Particle (MCNP) code. The experiments conducted with this new device made it possible to detect the

Gas chromatography-mass spectrometry and high-performance liquid chromatographic analyses of thermal degradation products of common plastics

OpenAIRE

Pacakova, V.; Leclercq, P.A.

1991-01-01

The thermo-oxidation of five commonly used materials, namely low-density polyethylene, retarded polyethylene, paper with a polyethylene foil, a milk package and filled polypropylene, was studied. Capillary gas chromatography and gas chromatography-mass spectrometry were used to analyze the volatile degradation products, while high-performance liquid chromatography was employed to measure polycyclic aromatic hydrocarbons. The results are discussed from the point of view of toxicity of the prod...

Application of EPR spectrometry, thermoluminescence, analyses of DNA damage and germination power for detection of irradiated foods

International Nuclear Information System (INIS)

Malec-Czechowska, K.; Stachowicz, W.; Dancewicz, A.M.; Szot, Z.

1999-01-01

The results of our own detection of irradiation in various foods: meat, poultry, fishes, spices, dried fruits, mushrooms, crops, fresh fruits and food additives are presented. The techniques for detection whether foods have been irradiated or not, such as EPR spectrometry, thermoluminescence (TL), DNA damage by ''comet'' method and ability for germination of grains has been discussed. The applicability of particular technique to specific foodstuffs has been indicated. (author)

Beach sediments drift study by means of radioactive tracers; L'etude du transport littoral par la methode des traceurs radioactifs

Energy Technology Data Exchange (ETDEWEB)

Hours, R [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Jaffry, P [Electricite de France (EDF), 78 - Chatou (France). Lab. National d' Hydraulique

1959-07-01

The present state of the sediments drift studies by means of radioactive tracers is exposed. Various processes of labelling, immersion and detection, used in France and other countries, are reviewed. A more extended analysis of some aspects of the problem by the same authors can be found in 'La Houille Blanche', number 3, may-june 1959 (Rapport C.E.A. number 1269). (author) [French] L'etude du transport littoral des sediments et galets par la methode des traceurs radioactifs est en plein developpement. Le present rapport precise l'etat actuel de la question. Les techniques de marquage, d'immersion et de detection utilisees en France et a l'etranger sont decrites; une analyse plus detaillee de certains aspects de la question est presentee par les memes auteurs dans 'La Houille Blanche', numero 3, mai-juin 1959 (Rapport C.E.A. numero 1269). (auteur)

Influencia de los parámetros de proceso, en el comportamiento del parámetro vibración absoluta en turbinas de vapor.

Directory of Open Access Journals (Sweden)

F. de la Torre Silva

2008-01-01

Full Text Available Este trabajo muestra el estudio realizado en turbinas de vapor de pequeña capacidad de generación de las centrales termoeléctricas cubanas, relacionadas con la influencia estadística entre parámetros de proceso de la turbina, respecto al parámetro vibración absoluta, medidos en las chumaceras de la turbina. Se utilizan las bases de datos de los sistemas de monitoreado on-line de la turbina. Se exponen las relaciones existentes entre los principales parámetros seleccionados para este estudio.This work show the study in small steam turbine capacity of generation in cubans thermoelectric power station to relative with statistical influence between steam process parameters regarding absolute vibration parameter, in the steam housing measurements. Themselves use database as steam on-line monitoring systems. Expose the existing relation between the principal selection parameters for this study.

Contamination potentielle des aliments par des ...

African Journals Online (AJOL)

SARA Computers

la notion de la pollution et de l'exposition aux PCBs, lorsque 77% n'ont pas conscience de cette situation de risque ... 2018). Quoique la contamination par les. PCBs soit de faible niveau, elle est ...... Université Paris-Est, Paris, France ; 183.

Methods of neutron spectrometry

International Nuclear Information System (INIS)

Doerschel, B.

1981-01-01

The different methods of neutron spectrometry are based on the direct measurement of neutron velocity or on the use of suitable energy-dependent interaction processes. In the latter case the measuring effect of a detector is connected with the searched neutron spectrum by an integral equation. The solution needs suitable unfolding procedures. The most important methods of neutron spectrometry are the time-of-flight method, the crystal spectrometry, the neutron spectrometry by use of elastic collisions with hydrogen nuclei, and neutron spectrometry with the aid of nuclear reactions, especially of the neutron-induced activation. The advantages and disadvantages of these methods are contrasted considering the resolution, the measurable energy range, the sensitivity, and the experimental and computational efforts. (author)

Collection and preparation of samples for gamma spectrometry

International Nuclear Information System (INIS)

Pan Jingquan

1994-01-01

The paper presents the basic principles of sample collection and preparation: setting up unified sampling program, methods and procedures, sample packing, transportation and storage, determination of sample quantity, sample pretreatment and preparation of samples to be analysed, etc. for gamma spectrometry. And the paper also describes briefly the main methods and special issues of sampling and preparation for the same environmental and biological samples, such as, air, water, grass, soil and foods

Accouchement par césarienne et mortalité maternelle du postpartum

OpenAIRE

Deneux-Tharaux , Catherine; Carmona , Elodie; Bouvier-Colle , Marie-Hélène; Bréart , Gérard

2006-01-01

Objectifs Une augmentation continue du taux d'accouchements par césarienne (CS)est observée dans la plupart des pays depuis 20 ans. Cette évolution a suscité l'émergence d'un débat controversé sur les risques et les bénéfices associés à la CS. L'objectif de cette étude était d'estimer le risque de mort maternelle du postpartum lié directement à la CS par comparaison à l'accouchement par voie basse, globalement et en distinguant les CS pre- ou intra- partum . Méthode Etude cas/témoins. Les cas...

Prise en charge des intoxications par envenimation chez les enfants ...

African Journals Online (AJOL)

Les signes cliniques étaient dominés par les douleurs (98%) suivies des hémorragies (73,80%) pour les morsures de serpent, la douleur pour les piqures de scorpion (100%) et les oedèmes pour les piqures d'abeilles (100%). Les cas de morsure de serpent ont été traités par le sérum antivenimeux polyvalent. Conclusion: ...

Contribution to the study of luminous sources for uranium isotope measurements by emission spectrometry; Contribution a l'etude de sources lumineuses destinees au dosage isotopique de l'uranium par spectrometrie d'emission

Energy Technology Data Exchange (ETDEWEB)

Leichnam, J P; Capitini, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1964-07-01

After a brief summary of results obtained with different hollow cathode luminous sources, the reasons for which they cannot be more widely used are given: an insufficient luminosity when uranium oxides are used in the cathode hollow; the large amount of sample required when it is metallic; the impossibility of effecting a chemical purification of the sample. Electrode-less discharge tubes excited by high frequency whose qualities (luminosity, stability, rapidity of preparation starting from small amounts of sample in various chemical forms, in particular iron) satisfy the conditions laid down for the measurement of uranium 235 by interferometry are used. Tho production process for such lamps is given together with the method of excitation. Examples of recordings obtained with an interferometer of the 'HYPEAC' type and a small grating spectrometer give an idea of the spectral qualities of these sources. (authors) [French] Apres avoir rappele les resultats obtenus avec differentes sources de lumiere a cathode creuse, on explique les raisons qui limitent leur emploi: brillance trop faible lorsque les oxydes d'uranium sont utilises dans le trou cathodique; trop grande quantite d'echantillon necessaire lorsque celui-ci est sous forme metallique; impossibilite de purifier chimiquement l'echantillon. On a employe des tubes a decharge sans electrode excitee par haute frequence, dont les qualites (brillance, stabilite, rapidite de preparation a partir de faibles quantites d'echantillon se presentant sous des formes chimiques diverses, elimination des impuretes chimiques, en particulier du fer) repondent aux conditions imposees pour le dosage isotopique de l'uranium 235 par interferometrie. On decrit le mode operatoire de fabrication de telles lampes et on rappelle le systeme d'excitation. Des exemples d'enregistrement, obtenus avec un appareil interferometrique 'HYPEAC' et un petit spectrometre a reseau, donnent une idee des qualites spectrales de ces sources. (auteurs)

Experimental study about the regulating effect of Par-4 gene overexpression on the nephroblastoma sensitivity to cisplatin

Directory of Open Access Journals (Sweden)

Hui-Lin Mao

2017-11-01

Full Text Available Objective: To study the regulating effect of Par-4 gene overexpression on the nephroblastoma sensitivity to cisplatin. Methods: Nephroblastoma SK-NEP-1 cells were cultured and divided into four groups, control group were treated with RMPI-1640 without serum or drugs, cisplatin group were treated with serum-free RMPI-1640 containing 5 μg/mL cisplatin, Par-4 group were transfected by Par-4 overexpression plasmids with serum-free RMPI-1640, and cisplatin + Par-4 group were transfected by Par-4 overexpression plasmid with serum-free RMPI-1640 containing 5 μg/mL cisplatin. The cell proliferation activity as well the expression of apoptosis genes, migration genes and invasion genes was measured. Results: 8 h, 16 h and 24 h after different conditions of treatment, the cell proliferation activity of cisplatin group, Par-4 group and cisplatin + Par-4 group were significantly lower than that of control group, and the cell proliferation activity of cisplatin + Par-4 group was significantly lower than that of cisplatin group and Par-4 group; 24 h after different conditions of treatment, Bim, PDCD4, WT1, RGS4, Axin, KAI1, E-cadherin, PPARγ and PTEN mRNA expression in cisplatin group, Par-4 group and cisplatin + Par-4 group were greatly higher than those in control group whereas GDNF, GFRα1, TUBB3, NME1 and FGF1 mRNA expression were greatly lower than those in control group; Bim, PDCD4, WT1, RGS4, Axin, KAI1, E-cadherin, PPARγ and PTEN mRNA expression in cisplatin + Par-4 group were greatly higher than those in cisplatin group and Par-4 group whereas GDNF, GFRα1, TUBB3, NME1 and FGF1 mRNA expression were greatly significantly lower than those in cisplatin group and Par-4 group. Conclusion: Par-4 gene overexpression can increase the nephroblastoma sensitivity to cisplatin, reduce cell proliferation activity, promote apoptosis and inhibit cell migration and invasion.

Inductively coupled plasma source mass spectrometry

International Nuclear Information System (INIS)

Price Russ, G. III

1993-01-01

Inductively coupled plasma source mass spectrometry (ICP-MS) is a relatively new (5 y commercial availability) technique for simultaneously determining the concentration and isotopic composition of a large number of elements at trace levels. The principle advantages of ICP-MS are the ability to measure essentially all the metallic elements at concentrations as low as 1 part in 10 12 by weight, to analyse aqueous samples directly, to determine the isotopic composition of essentially all the metallic elements, and to analyse samples rapidly (minutes). The history of the development of ICP-MS and discussions of a variety of applications have been discussed in detail in Date and Gray (1988). Koppenaal (1988, 1990) has reviewed the ICP-MS literature. In that ICP-MS is a relatively new and still evolving technique, this chapter will discuss potential capability more than proven performance. (author). 24 refs

Nanomechanical recognition of prognostic biomarker suPAR with DVD-ROM optical technology

International Nuclear Information System (INIS)

Bache, Michael; Bosco, Filippo G; Brøgger, Anna L; Frøhling, Kasper B; Boisen, Anja; Alstrøm, Tommy Sonne; Hwu, En-Te; Chen, Ching-Hsiu; Hwang, Ing-Shouh; Eugen-Olsen, Jesper

2013-01-01

In this work the use of a high-throughput nanomechanical detection system based on a DVD-ROM optical drive and cantilever sensors is presented for the detection of urokinase plasminogen activator receptor inflammatory biomarker (uPAR). Several large scale studies have linked elevated levels of soluble uPAR (suPAR) to infectious diseases, such as HIV, and certain types of cancer. Using hundreds of cantilevers and a DVD-based platform, cantilever deflection response from antibody–antigen recognition is investigated as a function of suPAR concentration. The goal is to provide a cheap and portable detection platform which can carry valuable prognostic information. In order to optimize the cantilever response the antibody immobilization and unspecific binding are initially characterized using quartz crystal microbalance technology. Also, the choice of antibody is explored in order to generate the largest surface stress on the cantilevers, thus increasing the signal. Using optimized experimental conditions the lowest detectable suPAR concentration is currently around 5 nM. The results reveal promising research strategies for the implementation of specific biochemical assays in a portable and high-throughput microsensor-based detection platform. (paper)

Effect of a physical activity intervention on suPAR levels

DEFF Research Database (Denmark)

Rohde, Christopher; Polcwiartek, Christoffer; Andersen, Eivind

2018-01-01

OBJECTIVES: Soluble urokinase-type plasminogen activator receptor (suPAR) is a novel inflammatory marker, associated with lifestyle diseases and mortality risk. No studies have investigated whether physical activity may reduce suPAR levels using a randomized controlled design. DESIGN AND METHODS......: suPAR and C-reactive protein (CRP) levels were determined in blood samples from a previous randomized controlled trial with Pakistani immigrants in Norway, 2008. The study included physically inactive men that were randomized to an intervention group (supervised group exercises) or a control group...... and followed for 5 months. A linear regression model was used and adjusted for age, inactivity level at baseline, and mean difference in CRP levels. RESULTS: Overall, 80 and 53 participants were included in the intervention and control group, respectively. Obesity and smoking were associated with higher su...

An electronic probe micro-analyser. A linear scan device; Microanalyseur a sonde electronique. Dispositif de balayage lineaire

Energy Technology Data Exchange (ETDEWEB)

Kirianenko, A; Maurice, F [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1963-07-01

The Castaing electronic probe micro-analyser makes possible static analysis at successive points. For two years this apparatus has been equipped by its constructor with an automatic device for surface scanning. In order to increase the micro-analyser's efficiency a 'linear' scan device has been incorporated making it possible to obtain semi-quantitative analyses very rapidly. (authors) [French] Le microanalyseur a sonde electronique de Castaing permet l'analyse statique en des points successifs. Depuis deux ans, cet appareil a ete equipe par son constructeur d'un dispositif de balayage automatique 'surface'. Afin d'augmenter l'efficacite du microanalyaeur, on a adapte un dispositif de balayage 'lineaire' qui permet d'obtenir tres rapidement des analyses semi-quantitative. (auteurs)

Testing Suitability of Cell Cultures for SILAC-Experiments Using SWATH-Mass Spectrometry.

Science.gov (United States)

Reinders, Yvonne; Völler, Daniel; Bosserhoff, Anja-K; Oefner, Peter J; Reinders, Jörg

2016-01-01

Precise quantification is a major issue in contemporary proteomics. Both stable-isotope-labeling and label-free methods have been established for differential protein quantification and both approaches have different advantages and disadvantages. The present protocol uses the superior precision of label-free SWATH-mass spectrometry to test for suitability of cell lines for a SILAC-labeling approach as systematic regulations may be introduced upon incorporation of the "heavy" amino acids. The SILAC-labeled cell cultures can afterwards be used for further analyses where stable-isotope-labeling is mandatory or has substantial advantages over label-free approaches such as pulse-chase-experiments and differential protein interaction analyses based on co-immunoprecipitation. As SWATH-mass spectrometry avoids the missing-value-problem typically caused by undersampling in highly complex samples and shows superior precision for the quantification, it is better suited for the detection of systematic changes caused by the SILAC-labeling and thus, can serve as a useful tool to test cell lines for changes upon SILAC-labeling.

uPA/uPAR system activation drives a glycolytic phenotype in melanoma cells.

Science.gov (United States)

Laurenzana, Anna; Chillà, Anastasia; Luciani, Cristina; Peppicelli, Silvia; Biagioni, Alessio; Bianchini, Francesca; Tenedini, Elena; Torre, Eugenio; Mocali, Alessandra; Calorini, Lido; Margheri, Francesca; Fibbi, Gabriella; Del Rosso, Mario

2017-09-15

In this manuscript, we show the involvement of the uPA/uPAR system in the regulation of aerobic glycolysis of melanoma cells. uPAR over-expression in human melanoma cells controls an invasive and glycolytic phenotype in normoxic conditions. uPAR down-regulation by siRNA or its uncoupling from integrins, and hence from integrin-linked tyrosine kinase receptors (IL-TKRs), by an antagonist peptide induced a striking inhibition of the PI3K/AKT/mTOR/HIF1α pathway, resulting into impairment of glucose uptake, decrease of several glycolytic enzymes and of PKM2, a checkpoint that controls metabolism of cancer cells. Further, binding of uPA to uPAR regulates expression of molecules that govern cell invasion, including extracellular matrix metallo-proteinases inducer (EMPPRIN) and enolase, a glycolytyc enzyme that also serves as a plasminogen receptor, thus providing a common denominator between tumor metabolism and phenotypic invasive features. Such effects depend on the α5β1-integrin-mediated uPAR connection with EGFR in melanoma cells with engagement of the PI3K-mTOR-HIFα pathway. HIF-1α trans-activates genes whose products mediate tumor invasion and glycolysis, thus providing the common denominator between melanoma metabolism and its invasive features. These findings unveil a unrecognized interaction between the invasion-related uPAR and IL-TKRs in the control of glycolysis and disclose a new pharmacological target (i.e., uPAR/IL-TKRs axis) for the therapy of melanoma. © 2017 UICC.

Analytical capabilities of laser-probe mass spectrometry

International Nuclear Information System (INIS)

Kovalev, I.D.; Madsimov, G.A.; Suchkov, A.I.; Larin, N.V.

1978-01-01

The physical bases and quantitative analytical procedures of laser-probe mass spectrometry are considered in this review. A comparison is made of the capabilities of static and dynamic mass spectrometers. Techniques are studied for improving the analytical characteristics of laser-probe mass spectrometers. The advantages, for quantitative analysis, of the Q-switched mode over the normal pulse mode for lasers are: (a) the possibility of analysing metals, semiconductors and insulators without the use of standards; and (b) the possibility of layer-by-layer and local analysis. (Auth.)

Proteinase-Activated Receptor-1 and Immunomodulatory Effects of a PAR1-Activating Peptide in a Mouse Model of Prostatitis

Science.gov (United States)

Stanton, M. Mark; Nelson, Lisa K.; Benediktsson, Hallgrimur; Hollenberg, Morley D.; Buret, Andre G.; Ceri, Howard

2013-01-01

Background. Nonbacterial prostatitis has no established etiology. We hypothesized that proteinase-activated receptor-1 (PAR1) can play a role in prostatitis. We therefore investigated the effects of PAR1 stimulation in the context of a new model of murine nonbacterial prostatitis. Methods. Using a hapten (ethanol-dinitrobenzene sulfonic acid- (DNBS-)) induced prostatitis model with both wild-type and PAR1-null mice, we examined (1) the location of PAR1 in the mouse prostate and (2) the impact of a PAR1-activating peptide (TFLLR-NH2: PAR1-TF) on ethanol-DNBS-induced inflammation. Results. Ethanol-DNBS-induced inflammation was maximal at 2 days. In the tissue, PAR1 was expressed predominantly along the apical acini of prostatic epithelium. Although PAR1-TF on its own did not cause inflammation, its coadministration with ethanol-DNBS reduced all indices of acute prostatitis. Further, PAR1-TF administration doubled the prostatic production of interleukin-10 (IL-10) compared with ethanol-DNBS treatment alone. This enhanced IL-10 was not observed in PAR1-null mice and was not caused by the reverse-sequence receptor-inactive peptide, RLLFT-NH2. Surprisingly, PAR1-TF, also diminished ethanol-DNBS-induced inflammation in PAR1-null mice. Conclusions. PAR1 is expressed in the mouse prostate and its activation by PAR1-TF elicits immunomodulatory effects during ethanol-DNBS-induced prostatitis. However, PAR1-TF also diminishes ethanol-DNBS-induced inflammation via a non-PAR1 mechanism by activating an as-yet unknown receptor. PMID:24459330

Solar PAR and UVR modify the community composition and photosynthetic activity of sea ice algae.

Science.gov (United States)

Enberg, Sara; Piiparinen, Jonna; Majaneva, Markus; Vähätalo, Anssi V; Autio, Riitta; Rintala, Janne-Markus

2015-10-01

The effects of increased photosynthetically active radiation (PAR) and ultraviolet radiation (UVR) on species diversity, biomass and photosynthetic activity were studied in fast ice algal communities. The experimental set-up consisted of nine 1.44 m(2) squares with three treatments: untreated with natural snow cover (UNT), snow-free (PAR + UVR) and snow-free ice covered with a UV screen (PAR). The total algal biomass, dominated by diatoms and dinoflagellates, increased in all treatments during the experiment. However, the smaller biomass growth in the top 10-cm layer of the PAR + UVR treatment compared with the PAR treatment indicated the negative effect of UVR. Scrippsiella complex (mainly Scrippsiella hangoei, Biecheleria baltica and Gymnodinium corollarium) showed UV sensitivity in the top 5-cm layer, whereas Heterocapsa arctica ssp. frigida and green algae showed sensitivity to both PAR and UVR. The photosynthetic activity was highest in the top 5-cm layer of the PAR treatment, where the biomass of the pennate diatom Nitzschia frigida increased, indicating the UV sensitivity of this species. This study shows that UVR is one of the controlling factors of algal communities in Baltic Sea ice, and that increased availability of PAR together with UVR exclusion can cause changes in algal biomass, photosynthetic activity and community composition. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

PAR-Complex and Crumbs Function During Photoreceptor Morphogenesis and Retinal Degeneration.

Science.gov (United States)

Pichaud, Franck

2018-01-01

The fly photoreceptor has long been used as a model to study sensory neuron morphogenesis and retinal degeneration. In particular, elucidating how these cells are built continues to help further our understanding of the mechanisms of polarized cell morphogenesis, intracellular trafficking and the causes of human retinal pathologies. The conserved PAR complex, which in flies consists of Cdc42-PAR6-aPKC-Bazooka, and the transmembrane protein Crumbs (Crb) are key players during photoreceptor morphogenesis. While the PAR complex regulates polarity in many cell types, Crb function in polarity is relatively specific to epithelial cells. Together Cdc42-PAR6-aPKC-Bazooka and Crb orchestrate the differentiation of the photoreceptor apical membrane (AM) and zonula adherens (ZA) , thus allowing these cells to assemble into a neuro-epithelial lattice. In addition to its function in epithelial polarity, Crb has also been shown to protect fly photoreceptors from light-induced degeneration, a process linked to Rhodopsin expression and trafficking. Remarkably, mutations in the human Crumbs1 (CRB1) gene lead to retinal degeneration, making the fly photoreceptor a powerful disease model system.

Potential Ecological Effects of Contaminants in the Exposed Par Pond Sediments

International Nuclear Information System (INIS)

Paller, M.H.; Wike, L.D.

1996-08-01

Sediment and small mammal samples were collected from the exposed sediments of Par Pond in early 1995, shortly before the reservoir was refilled after a 4-year drawdown. Sampling was confined to elevations between 58 and 61 meters (190 and 200 feet) above mean sea level, which includes the sediments likely to be exposed if the Par Pond water level is permitted to fluctuate naturally. Both soil and small mammal samples were analyzed for a number of radionuclides and metals. Some of the soil samples were also analyzed for organic contaminants. The objective of the study was to determine if contaminant levels in the Par Pond sediments were high enough to cause deleterious ecological effects

The pars intermedia: an anatomic basis for a coordinated vascular response to female genital arousal.

Science.gov (United States)

Shih, Cheryl; Cold, Christopher J; Yang, Claire C

2013-06-01

The pars intermedia is an area of the vulva that has been inconsistently described in the literature. We conducted anatomic studies to better describe the tissues and vascular structures of the pars intermedia and proposed a functional rationale of the pars intermedia in the female sexual response. Nine cadaveric vulvectomy specimens were used. Each was serially sectioned and stained with hematoxylin and eosin and Masson's trichrome. Histologic ultrastructural description of the pars intermedia. The pars intermedia contains veins traveling longitudinally in the angle of the clitoris, supported by collagen-rich stromal tissues. These veins drain the different vascular compartments of the vulva, including the clitoris, the bulbs, and labia minora; also, the interconnecting veins link the different vascular compartments. The pars intermedia is not composed of erectile tissue, distinguishing it from the erectile tissues of the corpora cavernosa of the clitoris as well as the corpus spongiosum of the clitoral (vestibular) bulbs. The venous communications of the pars intermedia, linking the erectile tissues with the other vascular compartments of the vulva, appear to provide the anatomic basis for a coordinated vascular response during female sexual arousal. © 2012 International Society for Sexual Medicine.

PAR-1 and thrombin: the ties that bind the microenvironment to melanoma metastasis.

Science.gov (United States)

Zigler, Maya; Kamiya, Takafumi; Brantley, Emily C; Villares, Gabriel J; Bar-Eli, Menashe

2011-11-01

Progression of melanoma is dependent on cross-talk between tumor cells and the adjacent microenvironment. The thrombin receptor, protease-activated receptor-1 (PAR-1), plays a key role in exerting this function during melanoma progression. PAR-1 and its activating factors, which are expressed on tumor cells and the surrounding stroma, induce not only coagulation but also cell signaling, which promotes the metastatic phenotype. Several adhesion molecules, cytokines, growth factors, and proteases have recently been identified as downstream targets of PAR-1 and have been shown to modulate interactions between tumor cells and the microenvironment in the process of melanoma growth and metastasis. Inhibiting such interactions by targeting PAR-1 could potentially be a useful therapeutic modality for melanoma patients. ©2011 AACR.

SECHAGE DE PRODUITS GRANULAIRES PAR DESHYDRATATION PAR DETENTES SUCCESSIVES (DDS)

OpenAIRE

Abdulla , Galal; Mellouk , Hamid; Belghit , Abdelhamid; Allaf , Karim

2009-01-01

International audience; Dans cette étude, nous avons évalué les performances d'un nouveau procédé de séchage dans le cas du liège en granulés. Ce procédé (La déshydratation par détentes successives : DDS) consiste à soumettre le matériau liège dans une chambre hermétique aux variations cycliques de la pression. Chaque cycle est composé d'une compression et d'une décompression. La phase de compression est réalisée en injectant de l'air comprimé à température ambiante provenant d'un compresseur...

Determination of Trace Iron in Red Wine by Isotope Dilution Mass Spectrometry Using Multiple-Collector Inductively Coupled Plasma Mass Spectrometry

International Nuclear Information System (INIS)

Zhou Tao; Wang Jun; Lu Hai; Zhou Yuanjing; Li Haifeng

2009-01-01

This paper introduces determination of trace iron in red wine certified reference material by isotope dilution mass spectrometry (IDMS) method using a multiplecollector inductively coupled plasma mass spectrometry, equipped with a hexapole collision cell. The measurement procedure of iron isotopic abundance ratios was deeply researched. Reduced polyatomic ion interferences to iron isotopes ion by collision reaction using Ar and H 2 gas, high precise isotopic abundance ratios were achieved. Two relative measurement methods (ICP-MS and ICP-OES) were used to analyze trace iron in red wine. The results are compared with IDMS results, which indicate that they are accordant. The uncertainty analyses include each uncertainty factor in whole experiment and the uncertainty of used certified reference material and it shows that the procedure blank is not neglectable to detect limit and precision of the method. The establishment of IDMS method for analysis of trace iron in red wine supports the certification of certified reference materials. (authors)

Par Pond vegetation status summer 1995 - July survey descriptive summary

International Nuclear Information System (INIS)

Mackey, H.E. Jr.; Riley, R.S.

1995-07-01

A survey of the emergent shoreline aquatic plant, communities began in June 1995, three months after the refilling of Par Pond to approximately 200 feet (61 meters) above mean sea level, and continued with this July survey. Aquatic plant communities, similar to the pre-drawdown Par Pond communities, are becoming reestablished. Beds of maidencane (Panicum hemitomon), lotus (Nelumbo lutea), water lily (Nymphaea odorata), and watershield (Brasenia schreberi) are now extensive and well established. In addition, within isolated coves, extensive beds of water lilies and spike-rush (Eleocharis sp.) are common. Cattail occurrence has increased since refill, but large beds common to Par Pond prior to the drawdown have not formed. Invasion of willow (Salix sp.) and red maple (Acer rubrum) occurred along the lake shoreline during drawdown. The red maples along the present shoreline are beginning to show evidence of stress and mortality from flooding over the past four months. Some of the willows appear to be stressed as well. The loblolly pines (Pinus taeda), which were flooded in all but the shallow shoreline areas, are now dead. Future surveys are planned for the growing seasons of 1995, 1996, and 1997, along with the evaluation of satellite data for mapping the areal extent of the macrophyte beds of Par Pond

Mass spectrometry imaging: Towards a lipid microscope?

Science.gov (United States)

Touboul, David; Brunelle, Alain; Laprévote, Olivier

2011-01-01

Biological imaging techniques are the most efficient way to locally measure the variation of different parameters on tissue sections. These analyses are gaining increasing interest since 20 years and allow observing extremely complex biological phenomena at lower and lower time and resolution scale. Nevertheless, most of them only target very few compounds of interest, which are chosen a priori, due to their low resolution power and sensitivity. New chemical imaging technique has to be introduced in order to overcome these limitations, leading to more informative and sensitive analyses for biologists and physicians. Two major mass spectrometry methods can be efficiently used to generate the distribution of biological compounds over a tissue section. Matrix-Assisted Laser Desorption/Ionisation-Mass Spectrometry (MALDI-MS) needs the co-crystallization of the sample with a matrix before to be irradiated by a laser, whereas the analyte is directly desorbed by a primary ion bombardment for Secondary Ion Mass Spectrometry (SIMS) experiments. In both cases, energy used for desorption/ionization is locally deposited -some tens of microns for the laser and some hundreds of nanometers for the ion beam- meaning that small areas over the surface sample can be separately analyzed. Step by step analysis allows spectrum acquisitions over the tissue sections and the data are treated by modern informatics software in order to create ion density maps, i.e., the intensity plot of one specific ion versus the (x,y) position. Main advantages of SIMS and MALDI compared to other chemical imaging techniques lie in the simultaneous acquisition of a large number of biological compounds in mixture with an excellent sensitivity obtained by Time-of-Flight (ToF) mass analyzer. Moreover, data treatment is done a posteriori, due to the fact that no compound is selectively marked, and let us access to the localization of different lipid classes in only one complete acquisition. Copyright © 2010

Chemical analysis of zinc electroplating solutions by x-ray fluorescence spectrometry

International Nuclear Information System (INIS)

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)

Project Plan 7930 Cell G PaR Remote Handling System Replacement

International Nuclear Information System (INIS)

Kinney, Kathryn A.

2009-01-01

For over 40 years the US Department of Energy (DOE) and its predecessors have made Californium-252 ( 252 Cf) available for a wide range of industries including medical, nuclear fuels, mining, military and national security. The Radiochemical Engineering Development Center (REDC) located within the Oak Ridge National Laboratory (ORNL) processes irradiated production targets from the High Flux Isotope Reactor (HFIR). Operations in Building 7930, Cell G provide over 70% of the world's demand for 252 Cf. Building 7930 was constructed and equipped in the mid-1960s. Current operations for 252 Cf processing in Building 7930, Cell G require use of through-the-wall manipulators and the PaR Remote Handling System. Maintenance and repairs for the manipulators is readily accomplished by removal of the manipulator and relocation to a repair shop where hands-on work can be performed in glove boxes. Contamination inside cell G does not currently allow manned entry and no provisions were created for a maintenance area inside the cell. There has been no maintenance of the PaR system or upgrades, leaving operations vulnerable should the system have a catastrophic failure. The Cell G PaR system is currently being operated in a run to failure mode. As the manipulator is now 40+ years old there is significant risk in this method of operation. In 2006 an assessment was completed that resulted in recommendations for replacing the manipulator operator control and power centers which are used to control and power the PaR manipulator in Cell G. In mid-2008 the chain for the bridge drive failed and subsequent examinations indicated several damaged links (see Figure 1). To continue operations the PaR manipulator arm is being used to push and pull the bridge as a workaround. A retrieval tool was fabricated, tested and staged inside Cell G that will allow positioning of the bridge and manipulator arm for removal from the cell should the PaR system completely fail. A fully functioning and

Évaluation des services rendus par les écosystèmes  en France

Directory of Open Access Journals (Sweden)

Philippe Blancher

2011-12-01

Full Text Available Cet article rend compte de la méthode d’évaluation des services écosystémiques appliquée au territoire français dans le cadre d’une approche exploratoire. S’inscrivant dans le sillage du ‘‘Millennium Ecosystem Assessment’’ (MA lancé par l’ONU, l’application de la démarche du MA à un territoire donné a conduit à l’élaboration de nouveaux outils d’analyse et de mesure des interactions entre nature et activités humaines à plusieurs échelles territoriales, à travers une projection cartographique des écosystèmes sur l’ensemble du territoire, un recensement des services rendus par les écosystèmes en France et une méthodologie pour leur quantification.This article introduces a method for the assessment of ecosystem services on the French territory. Following the U.N.-initiated Millennium Ecosystem Assessment framework, the implementation of an ecosystem assessment on a specific territory led to the conception of new tools for the analysis and the measurement of interactions between nature and human activities at different territorial scales, through the mapping of ecosystems, an identification of ecosystem services on the French territory and a methodology for their quantification.

Problems raised by pulse analysers - functional multi-dimensional analysers; Problemes poses par les analyseurs en impulsions - Analyseurs multidimensionnels fonctionnels; Problemy, voznikayushchie v svyazi s ispol'zovaniem analizatorov impul'sov - funktsional'nye mnogorazmernye analizatory; Problemas planteados por los analizadores de impulsos - Analizadores multidimensionales funcionales

Energy Technology Data Exchange (ETDEWEB)

Pages, A [Centre d' Etudes Nucleaires de Saclay (France)

1962-04-15

de nombreuses raisons: le nombre de parametres possibles est beaucoup trop reduit (deblocage seulement sur les analyseurs 100 et 256 canaux) ainsi que leur capacite; cette limitation multiplie considerablement le temps d'accelerateur; parfois l'experience est rendue impossible par le mauvais de ces analyseurs; par ailleurs, etant concus en un seul , ils manquent de d'utilisation. Un appareil multidimensionnel limite a 2 voies de 63 canaux a ete etudie et construit en 1958-59. Une separation est faite entre les differentes fonctions essentielles: analyse, transfert (fonctionnement en multidimensionnel) et exploitation des resultats. MM. Amram, Guillon et Thenard etudient et construisent a la SEG un analyseur multidimensionnel 1023 canaux x 63 canaux (destine au groupe de mesures de vitesses de neutrons de la SPNBE). Par ailleurs, afin de repondre aux limitations precedemment formulees, le laboratoire d'electronique de la SPNBE realise un analyseur multidimensionnel fonctionnel, ou la fonction de transfert a ete elle-meme decomposee en unites (rythmeur, memoire non integratrice, conditionneur et calculateur). Les types d'unites choisies sont, comme les limites definissant les voies, variables en fonction des besoins et de la complexite de l'experience (langage standard interfonctionnel). (author) [Spanish] Los investigadores emplean cada vez con mayor frecuencia conjuntos analizadores que permiten obtener una funcion de varios parametros (el numero de parametros y la precision relativa de cada uno de ellos puede variar de un experimento a otro). Por muchas razones, los analizadores actuales no se prestan bien para los experimentos, que son cada dia mas complejos: el numero de parametros posibles es excesivamente pequeno (desbloqueo solo en los analizadores de 100 y 256 canales) y tambien lo es su capacidad; esta limitacion multiplica considerablemente el tiempo de acelerador. Algunas veces, el bajo ''rendimiento'' de estos analizadores

Injures onomasti et public : éléments pour une analyse interactionnelle.

Directory of Open Access Journals (Sweden)

Rossella Saetta Cottone

2007-07-01

Full Text Available Cet article se propose de mettre en lumière les dynamiques interactionnelles mises en œuvre par la pratique comique de l’onomasti kômôidein, à travers le recours à certaines instruments théoriques fournis par la socio-linguistique (analyse interactionnelle et conversationnelle. En soulignant l’analogie existante entre les injures que les acteurs adressent contre des citoyens réels appelés par leur nom et la calomnie, la diabolè,  il propose de nuancer l’opposition, qui domine la critique aristophanienne, entre les interprétations « ritualistes » et les interprétations « politiques » de ce phénomène dramatique.This article aims to shed light on the interactional dynamics created by the comic practice of onomasti kômôidein, making use of some theoretical tools provided by sociolinguistics (interactional and conversational analysis in particular. By illuminating the analogy that exists between the insults aimed by actors at actual citizens called by their real names on the one hand, and slander (diabolè on the other hand, this paper seeks to give nuance to an opposition which dominates Aristophanic criticism: between "ritualist" and "political" interpretations of the dramatic phenomenon in question.

Structural Elucidation of cis / trans Dicaffeoylquinic Acid Photoisomerization Using Ion Mobility Spectrometry-Mass Spectrometry

Energy Technology Data Exchange (ETDEWEB)

Zheng, Xueyun; Renslow, Ryan S.; Makola, Mpho M.; Webb, Ian K.; Deng, Liulin; Thomas, Dennis G.; Govind, Niranjan; Ibrahim, Yehia M.; Kabanda, Mwadham M.; Dubery, Ian A.; Heyman, Heino M.; Smith, Richard D.; Madala, Ntakadzeni E.; Baker, Erin S.

2017-03-15

Due to the recently uncovered health benefits and anti-HIV activities of dicaffeoylquinic acids (diCQAs), understanding their structures and functions is of great interest for drug discovery efforts. DiCQAs are analytically challenging to identify and quantify since they commonly exist as a diverse mixture of positional and geometric (cis/trans) isomers. In this work, we utilized ion mobility spectrometry coupled with mass spectrometry to separate the various isomers before and after UV irradiation. The experimental collision cross sections were then compared with theoretical structures to differentiate and identify the diCQA isomers. Our analyses found that naturally the diCQAs existed predominantly as trans/trans isomers, but after 3 h of UV irradiation, cis/cis, cis/trans, trans/cis, and trans/trans isomers were all present in the mixture. This is the first report of successful differentiation of cis/trans diCQA isomers individually, which shows the great promise of IMS coupled with theoretical calculations for determining the structure and activity relationships of different isomers in drug discovery studies.

PAR-1 mediated apoptosis of breast cancer cells by V. cholerae hemagglutinin protease.

Science.gov (United States)

Ray, Tanusree; Pal, Amit

2016-05-01

Bacterial toxins have emerged as promising agents in cancer treatment strategy. Hemagglutinin (HAP) protease secreted by Vibrio cholerae induced apoptosis in breast cancer cells and regresses tumor growth in mice model. The success of novel cancer therapies depends on their selectivity for cancer cells with limited toxicity for normal tissues. Increased expression of Protease Activated Receptor-1 (PAR-1) has been reported in different malignant cells. In this study we report that HAP induced activation and over expression of PAR-1 in breast cancer cells (EAC). Immunoprecipitation studies have shown that HAP specifically binds with PAR-1. HAP mediated activation of PAR-1 caused nuclear translocation of p50-p65 and the phosphorylation of p38 which triggered the activation of NFκB and MAP kinase signaling pathways. These signaling pathways enhanced the cellular ROS level in malignant cells that induced the intrinsic pathway of cell apoptosis. PAR-1 mediated apoptosis by HAP of malignant breast cells without effecting normal healthy cells in the same environment makes it a good therapeutic agent for treatment of cancer.

Fast neutron spectrometry and dosimetry; Spectrometrie et dosimetrie des neutrons rapides

Energy Technology Data Exchange (ETDEWEB)

Blaize, S; Ailloud, J; Mariani, J; Millot, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

We have studied fast neutron spectrometry and dosimetry through the recoil protons they produce in hydrogenated samples. In spectrometric, we used nuclear emulsions, in dosimetric, we used polyethylene coated with zinc sulphide and placed before a photomultiplier. (author)Fren. [French] Nous avons etudie la spectrometrie et la dosimetrie des neutrons rapides en utilisant les protons de recul qu'ils produisent dans une matiere hydrogenee. En spectrometrie, nous avons employe des emulsions nucleaires, en dosimetrie, du polyethylene recouvert de sulfure de zinc place devant un photomultiplicateur. (auteur)

Comparaison du Pangola (Digitaria decumbens) et du Stargrass (Cynodon nlemfluensis) exploités par des ovins

OpenAIRE

Boval, Maryline

1989-01-01

A la Martinique l'utilisation comparée de Digitaria decumbens (Dd) et de Cynodon nlemfuensis (Cn) par des brebis allaitantes a été étudiée pendant une période d'observation de 6 mois. Le cheptel est à un taux élevé de 1 600 kg de poids vif par hectare et par an, obtenu par une fertilisation de 450 kg/ha/an en azote.

ParFit: A Python-Based Object-Oriented Program for Fitting Molecular Mechanics Parameters to ab Initio Data.

Science.gov (United States)

Zahariev, Federico; De Silva, Nuwan; Gordon, Mark S; Windus, Theresa L; Dick-Perez, Marilu

2017-03-27

A newly created object-oriented program for automating the process of fitting molecular-mechanics parameters to ab initio data, termed ParFit, is presented. ParFit uses a hybrid of deterministic and stochastic genetic algorithms. ParFit can simultaneously handle several molecular-mechanics parameters in multiple molecules and can also apply symmetric and antisymmetric constraints on the optimized parameters. The simultaneous handling of several molecules enhances the transferability of the fitted parameters. ParFit is written in Python, uses a rich set of standard and nonstandard Python libraries, and can be run in parallel on multicore computer systems. As an example, a series of phosphine oxides, important for metal extraction chemistry, are parametrized using ParFit. ParFit is in an open source program available for free on GitHub ( https://github.com/fzahari/ParFit ).

Analytical studies by activation. Part A and B: Counting of short half-life radio-nuclides. Part C: Analytical programs for decay curves; Etudes d'analyse par activation. Parties A et B: le comptage des radio-nucleides de periodes courtes. Partie C: programme de depouillement des courbes de decroissance

Energy Technology Data Exchange (ETDEWEB)

Junod, E [Commissariat a l' Energie Atomique Grenoble (France). Centre d' Etudes Nucleaires

1966-03-01

est consacree au probleme des corrections de pertes au comptage dues au temps mort des analyseurs multicanaux. On a etabli les formules de correction exactes lorsque le radionucleide de periode courte est pur ou seulement accompagne d'un radionucleide de periode longue. Par comparaison on a trace sous forme d'abaques les approximations fournies par le comptage dit 'en temps actif' et par un mode de comptage en temps reel associe a la mesure du temps mort global, ce second procede se revelant plus valable que le premier. Dans le cas d'un melange complexe, on donne le moyen de le ramener au probleme a deux constituants. Partie C: On presente les problemes que pose l'analyse qualitative et quantitative des courbes de decroissance d'un melange de sources radioactives dont au moins une de periode courte. Six procedes fondamentaux sont decrits mathematiquement pour lesquels sont proposes des elements de programmes fortran. Deux programmes supplementaires sont construits pour traiter globalement des problemes de dosages en analyse par activation: l'un base sur l'irradiation simultanee d'un echantillon et d'un ou plusieurs temoins; l'autre sur l'irradiation separee de l'echantillon et du temoin, un dosimetre (par activation ou exterieur) servant a normaliser les conditions de flux d'irradiation.

Application of passive auto catalytic recombiner (PAR) for BWR plants in Japan

International Nuclear Information System (INIS)

Kobayashi, K.; Murano, K.; Yamanari, S.; Yamamoto, Y.

2001-01-01

The passive auto-catalytic recombiner (PAR), which can recombine flammable gases such as hydrogen and oxygen with each other to avoid an explosion in case of a loss-of-coolant accident (LOCA), installed in the primary containment vessel does not require a power supply or dynamic equipment, while the existing flammability gas control system (FCS) of most BWRs as an outer loop of the primary containment vessel needs them to make flammable gases circulate through blowers and heaters in the system. PAR offers a number of advantages over existing FCS, such as high reliability, low cost due to much smaller amount of materials needed, good maintainability, good operability in case of a LOCA, and smaller space for installation. An experimental study has been carried out for the purpose of solving the problems of applying PAR to Japanese BWR plants instead of existing FCS, in which we grasped the basic characteristics of PAR. (author)

Identification and imaging of modern paints using Secondary Ion Mass Spectrometry with MeV ions

DEFF Research Database (Denmark)

Bogdanović Radović, Iva; Siketić, Zdravko; Jembrih-Simbürger, Dubravka

2017-01-01

Secondary Ion Mass Spectrometry using MeV ion excitation was applied to analyse modern paint materials containing synthetic organic pigments and binders. It was demonstrated that synthetic organic pigments and binder components with molecular masses in the m/z range from 1 to 1200 could be identi......Secondary Ion Mass Spectrometry using MeV ion excitation was applied to analyse modern paint materials containing synthetic organic pigments and binders. It was demonstrated that synthetic organic pigments and binder components with molecular masses in the m/z range from 1 to 1200 could...... be identified in different paint samples with a high efficiency and in a single measurement. Different ways of mounting of mostly insulating paint samples were tested prior to the analysis in order to achieve the highest possible yield of pigment main molecular ions. As Time-of-Flight mass spectrometer for Me......V Secondary Ion Mass Spectrometry is attached to the heavy ion microprobe, molecular imaging on cross-sections of small paint fragments was performed using focused ions. Due to the fact that molecules are extracted from the uppermost layer of the sample and to avoid surface contamination, the paint samples...

Pars plana Ahmed valve and vitrectomy in patients with glaucoma associated with posterior segment disease.

Science.gov (United States)

Wallsh, Josh O; Gallemore, Ron P; Taban, Mehran; Hu, Charles; Sharareh, Behnam

2013-01-01

To assess the safety and efficacy of a modified technique for pars plana placement of the Ahmed valve in combination with pars plana vitrectomy in the treatment of glaucoma associated with posterior segment disease. Thirty-nine eyes with glaucoma associated with posterior segment disease underwent pars plana vitrectomy combined with Ahmed valve placement. All valves were placed in the pars plana using a modified technique, without the pars plana clip, and using a scleral patch graft. The 24 eyes diagnosed with neovascular glaucoma had an improvement in intraocular pressure from 37.6 mmHg to 13.8 mmHg and best-corrected visual acuity from 2.13 logarithm of minimum angle of resolution to 1.40 logarithm of minimum angle of resolution. Fifteen eyes diagnosed with steroid-induced glaucoma had an improvement in intraocular pressure from 27.9 mmHg to 14.1 mmHg and best-corrected visual acuity from 1.38 logarithm of minimum angle of resolution to 1.13 logarithm of minimum angle of resolution. Complications included four cases of cystic bleb formation and one case of choroidal detachment and explantation for hypotony. Ahmed valve placement through the pars plana during vitrectomy is an effective option for managing complex cases of glaucoma without the use of the pars plana clip.

La syphilis congenitale revelee par une fracture spontanee

Directory of Open Access Journals (Sweden)

Mounia Lakhdar Idrissi

2011-11-01

Full Text Available Alors qu�elle est actuellement oubliee dans les pays developpes, la syphilis congenitale se voit encore chez nous faute du depistage antenatal. Ses formes cliniques sont polymorphes et orientent a tord vers d�autres pathologies surtout en periode neonatale. Le diagnostic n�est donc pas toujours facile. La revelation d�une syphilis congenitale par une fracture spontanee est exceptionnellement decrite. Nous rapportons dans ce travail le cas d�un nourrisson de 2 mois ramene en consultation pour limitation douloureuse des mouvements du bras droit. Le diagnostic est evoque sur les donnees radiologiques et confirme par la serologie syphilitique. Le traitement a repose essentiellement sur l�administration de la penicilline G avec une bonne evolution clinique.

[Roles of protease-activated receptor-2 (PAR-2), a G protein-coupled receptor, in modulation of exocrine gland functions].

Science.gov (United States)

Nishikawa, Hiroyuki

2006-07-01

Protease-activated receptor-2 (PAR-2), a G protein-coupled receptor, is activated by proteolytic unmasking of the N-terminal extracellular tethered ligand that presumably binds to the extracellular loop 2 of the receptor itself. PAR-2 is widely distributed in the mammalian body and plays various roles in biological events in the cardiovascular, respiratory, alimentary, and central neurons systems. PAR-2-activating peptides administered systemically to mice and rats trigger prompt salivation in vivo. In an in vitro study, PAR-2 agonists including the endogenous PAR-2 activator trypsin induce secretion of amylase and mucin from isolated rat parotid glands and sublingual glands, respectively. PAR-2-activating peptides administered systemically also modulate pancreatic exocrine secretion in vivo as well as in vitro. In the gastric mucosa, PAR-2 stimulation enhances secretion of mucus and pepsinogen and suppresses acid secretion. Tear secretion can also be caused by PAR-2-related peptides in PAR-2-dependent and -independent manners. PAR-2 thus plays a general or key role in the regulation of exocrine secretion. This review focuses on the physiologic and/or pathophysiologic roles of PAR-2 in glandular exocrine secretion. The possibility of PAR-2 as a target for drug development is also discussed.

Cluster secondary ion mass spectrometry microscope mode mass spectrometry imaging.

Science.gov (United States)

Kiss, András; Smith, Donald F; Jungmann, Julia H; Heeren, Ron M A

2013-12-30

Microscope mode imaging for secondary ion mass spectrometry is a technique with the promise of simultaneous high spatial resolution and high-speed imaging of biomolecules from complex surfaces. Technological developments such as new position-sensitive detectors, in combination with polyatomic primary ion sources, are required to exploit the full potential of microscope mode mass spectrometry imaging, i.e. to efficiently push the limits of ultra-high spatial resolution, sample throughput and sensitivity. In this work, a C60 primary source was combined with a commercial mass microscope for microscope mode secondary ion mass spectrometry imaging. The detector setup is a pixelated detector from the Medipix/Timepix family with high-voltage post-acceleration capabilities. The system's mass spectral and imaging performance is tested with various benchmark samples and thin tissue sections. The high secondary ion yield (with respect to 'traditional' monatomic primary ion sources) of the C60 primary ion source and the increased sensitivity of the high voltage detector setup improve microscope mode secondary ion mass spectrometry imaging. The analysis time and the signal-to-noise ratio are improved compared with other microscope mode imaging systems, all at high spatial resolution. We have demonstrated the unique capabilities of a C60 ion microscope with a Timepix detector for high spatial resolution microscope mode secondary ion mass spectrometry imaging. Copyright © 2013 John Wiley & Sons, Ltd.

Dispersive liquid-liquid microextraction followed by flow injection-inductively coupled plasma mass spectrometry (FI-ICPMS) determination of 14 lanthanides from ground water

International Nuclear Information System (INIS)

Chandrasekaran, K.; Karunasagar, D.; Arunachalam, J.

2011-01-01

The aim of the present work was to develop a dispersive liquid-liquid microextraction (DLLME) method for the sensitive determination of REEs at a few parts per billion in groundwater by flow injection-inductively coupled plasma mass spectrometry (FI-ICPMS). In the developed method, methanol (500 μl) and chloroform (200μl) were used as the disperser and extractant respectively. The REEs were complexed with 4-(2-pyridylazo resorcinol) (PAR) at a pH of 7. Acetate ion was added as an auxiliary ligand for neutralization of the charge on the lanthanide-PAR complex. The disperser (MeOH) - extraction solvent (CHCl 3 ) mixture was rapidly injected using a disposable syringe, thereby forming a cloudy solution. The lanthanide-PAR complex was extracted into the fine droplets of the chloroform dispersed in the aqueous phase. The solution was centrifuged and the aqueous layer at the top was discarded. The REEs were back extracted from the chloroform layer with nitric acid for determination by ICPMS. Important parameters for complex formation and extraction, such as volume of extraction/disperser solvent, extraction time, pH and concentration of the chelating agent and the auxiliary ligand are being optimized using ICP-MS. The optimization is being carried out at 5 μg L -1 concentration level of REE in the initial water sample. Preliminary studies have shown an extraction recovery of 80-85% for all the 14 lanthanide elements and these will be presented

Comparison of Direct Pars Repair Techniques of Spondylolysis in Pediatric and Adolescent Patients: Pars Compression Screw Versus Pedicle Screw-Rod-Hook.

Science.gov (United States)

Karatas, Ali F; Dede, Ozgur; Atanda, Alfred A; Holmes, Larry; Rogers, Kenneth; Gabos, Peter; Shah, Suken A

2016-08-01

Retrospective clinical cohort study. To compare the clinical and radiographic outcomes of patients who were treated with intrasegmental pars fixation by either laminar compression screw (LS) or a pedicle screw, rod, and laminar hook (PSRH) construct. Spondylolysis is a nonunion defect of the pars interarticularis. In symptomatic spondylolysis, direct repair of the pars interarticularis defect can preserve motion and prevent abnormal stresses at the adjacent levels. Sixteen patients who failed nonoperative treatment and underwent direct pars repair by using LS (n=9) or PSRH (n=7) constructs were included in the study. Clinical outcome was assessed by using the MacNab criteria. Radiologic fusion and complications were evaluated using plain radiographs or computed tomography images and patient charts. The healing rate was 100% after 6 months. The healing time was similar in both the groups: LS, 6.5 months; PSRH, 6.2 months. Patients with PSRH (5.9 mo) were more likely to return to sports earlier relative to patients with LS (7.7 mo). There were no complications in the LS group; in the PSRH group, 1 patient had mild sensory deficit and 2 had superficial wound infections. The MacNab criteria for pain assessment showed an excellent or good outcome in 8 of 9 patients in LS group and 6 of 7 patients in PSRH group. Relative to LS patients, there was a significant increase in surgical time and estimated blood loss among PSRH patients. Either of the mentioned 2 techniques appears to produce acceptable results. Biplanar fluoroscopy and navigation systems could minimize the risk of screw misplacement with LS construct. Familiarity with the various fixation techniques will allow the surgeon to select the most appropriate surgical technique.

DNA adducts: Mass spectrometry methods and future prospects

International Nuclear Information System (INIS)

Farmer, P.B.; Brown, K.; Tompkins, E.; Emms, V.L.; Jones, D.J.L.; Singh, R.; Phillips, D.H.

2005-01-01

Detection of DNA adducts is widely used for the monitoring of exposure to genotoxic carcinogens. Knowledge of the nature and amounts of DNA adducts formed in vivo also gives valuable information regarding the mutational effects that may result from particular exposures. The power of mass spectrometry (MS) to achieve qualitative and quantitative analyses of human DNA adducts has increased greatly in recent years with the development of improved chromatographic interfaces and ionisation sources. Adducts have been detected on nucleic acid bases, 2'-deoxynucleosides or 2'-deoxynucleotides, with LC-MS/MS being the favoured technique for many of these analyses. Our current applications of this technique include the determination of N7-(2-carbamoyl-2-hydroxyethyl)-guanine, which was postulated to be found as a DNA repair product in urine following exposure to acrylamide, and of 8-oxo-7,8-dihydro-2'-deoxyguanosine and 8-oxo-7,8-dihydro-2'-deoxyadenosine, as markers of oxidative damage in human lymphocyte DNA. Higher sensitivity (with a detection limit of 1-10 adducts/10 12 nucleotides) may be achieved by the use of accelerator mass spectrometry (AMS), although this requires the presence of certain isotopes, such as [ 14 C], in the material being analysed. In order to make this technique more amenable for studies of human exposure to environmental carcinogens, new postlabelling techniques, incorporating [ 14 C] into specific DNA adducts after formation, are being developed. It is expected that combining the use of advanced MS techniques with existing 32 P-postlabelling and immunochemical methodologies will contribute greatly to the understanding of the burden of human exposure to environmental carcinogens

PAR-Complex and Crumbs Function During Photoreceptor Morphogenesis and Retinal Degeneration

Directory of Open Access Journals (Sweden)

Franck Pichaud

2018-03-01

Full Text Available The fly photoreceptor has long been used as a model to study sensory neuron morphogenesis and retinal degeneration. In particular, elucidating how these cells are built continues to help further our understanding of the mechanisms of polarized cell morphogenesis, intracellular trafficking and the causes of human retinal pathologies. The conserved PAR complex, which in flies consists of Cdc42-PAR6-aPKC-Bazooka, and the transmembrane protein Crumbs (Crb are key players during photoreceptor morphogenesis. While the PAR complex regulates polarity in many cell types, Crb function in polarity is relatively specific to epithelial cells. Together Cdc42-PAR6-aPKC-Bazooka and Crb orchestrate the differentiation of the photoreceptor apical membrane (AM and zonula adherens (ZA, thus allowing these cells to assemble into a neuro-epithelial lattice. In addition to its function in epithelial polarity, Crb has also been shown to protect fly photoreceptors from light-induced degeneration, a process linked to Rhodopsin expression and trafficking. Remarkably, mutations in the human Crumbs1 (CRB1 gene lead to retinal degeneration, making the fly photoreceptor a powerful disease model system.

L’ANALYSE DU DISCOURS DE LA RESPONSABILITE SOCIALE DE L’ENTREPRISE A TRAVERS LES RAPPORTS ANNUELS DE DEVELOPPEMENT DURABLE D’ ENTREPRISES FRANÇAISES DU CAC 40

Directory of Open Access Journals (Sweden)

Jacques IGALENS

2006-01-01

Full Text Available Sous la pression des parties prenantes, le nombre de rapports dedéveloppement durable ne cesse d'augmenter. Jusqu'ici les méthodesd'analyse des informations qu'ils contiennent sont essentiellementcomptables. L'enjeu de ces rapports va au-delà des indicateurs chiffrésfournis par exemple par la GRI, Global Reporting Initiative. Il s'agit pour uneentreprise de légitimer son action et les conséquences de son action dansles domaines sociaux, environnementaux et societaux. La place tenue par lediscours dans ces rapports est essentielle et la méthode proposée dans cetarticle est ainsi celle de "l'analyse des discours" notamment en s'appuyantsur les caractéristiques de l'énonciation et sur celles des procédésrhétoriques. Ainsi apparaît que les entreprises ne se contentent pas de "faireun rapport" mais qu'elles essaient de construire un monde, un monde danslequel elles se présentent en héros positif, un monde dont elles définissentles règles.

Mass spectrometry of submicrogram quantities of lead and cadmium

International Nuclear Information System (INIS)

Moraes, Noemia M.P. de; Kakazu, M.H.; Iyer, S.S.

1980-01-01

Isotope analyses of submicrogram quantities of lead and cadmium are carried out by single filament solid source mass spectrometry. Thermionic emission of Pb and Cd is enhanced using silica gel as an emitter. Details of the chemical and mass spectrometric techniques are described. The low blank levels are maintained by extra purification of the reagents. The applications of isotope ratios of Pb and Cd in environmental sciences and geochemistry are discussed. (Author) [pt

Delineation of pulmonary airway fluid protein fractions with HRPO binding-avidity by far-Western ligand blot and mass spectrometry analyses: a model methodology for detecting mannose-binding protein expression profiles.

Science.gov (United States)

Coyne, Cody P; Rashmir-Raven, Ann; Jones, Toni; Mochal, Cathleen; Linford, Robert L; Brashier, Michael; Eddy, Alison

2009-01-01

Limited research to date has characterized the potential for HRPO to function as a primary molecular probe. Pulmonary airway fluid was developed by non-reducing far-Western (ligand) blot analyses utilizing conjugated HRPO-strepavidin or non-conjugated HRPO without the presence of primary immunoglobulin. Endogenous esterase-like biochemical activity of fractions within pulmonary airway fluid was inactivated to determine if they were capable of biochemically converting HRPO chemiluminescent substrate. Complementary analyses modified pulmonary fluid and HRPO with beta-galactosidase and alpha-mannosidase respectively, in addition to determining the influence of mannose and maltose competitive binding on HRPO far-Western (ligand) blot analyses. Identification of pulmonary fluid fractions detected by HRPO far-Western blot analyses was determined by mass spectrometry. Modification of pulmonary fluid with beta-galactosidase, and HRPO with alpha-mannosidase in concert with maltose and mannose competitive binding analyses altered the intensity and spectrum of pulmonary fluid fractions detected by HRPO far-Western blot analysis. Identity of pulmonary airway fluid fractions detected by HRPO far-Western (ligand) blot analysis were transferrin, dynein, albumin precursor, and two 156 kDa equine peptide fragments. HRPO can function as a partially-selective primary molecular probe when applied in either a conjugated or non-conjugated form. Some protein fractions can form complexes with HRPO through molecular mechanisms that involve physical interactions at the terminal alpha-mannose-rich regions of HRPO glycan side-chains. Based on its known molecular composition and structure, HRPO provides an opportunity for the development of diagnostics methodologies relevant to disease biomarkers that possess mannose-binding avidity.

Analyse de discours et inégalités sociales: de l’empathie pour les invisibles à l’engagement pour le commun

Directory of Open Access Journals (Sweden)

Alain Rabatel

2016-12-01

Full Text Available L’article analyse le lien entre inégalités sociales et invisibilité puis étudie quelques exemples de luttes de reconnaissance. Il interroge ensuite les précautions à prendre pour que l’analyse de discours rende compte de l’invisibilité sociale lorsqu’elle est redoublée par l’invisibilité médiatique et linguistique – avec des phénomènes d’effacement énonciatif, de naturalisation, de prise en compte énonciative qui ne vont pas jusqu’à la prise en charge. À cette fin, il liste des conditions épistémologiques, méthodologiques et théoriques faisant système concernant: l’articulation entre linguistique et réalité extralinguistique; la problématisation de la notion de représentation; le rapport des corpus marginaux à la norme; l’interprétation de la dualité marqué/non marqué en termes de continuums; la prise en compte des stratégies de communication formatées par les situations, par les choix discursifs révélateurs des intentions des locuteurs; une analyse de discours critique (aux antipodes des postures de dénonciation en appui sur des vérités monologiques; le choix de l’interdisciplinarité; l’analyse empathique – non seulement envers différents acteurs, mais envers des groupes, des façons de penser conflictuelles –, afin de pouvoir mieux penser la place et la contribution des uns et des autres dans la co-construction d’un (bien commun partagé.

Etude par simulation hil des performances d'un statcom pour la ...

African Journals Online (AJOL)

Ce travail présente l'étude par simulation Hardware In the Loop (HIL) des performances d'un STATCOM pour la stabilisation de la tension délivrée par une génératrice asynchrone triphasée auto excitée dans un réseau autonome. Nous avons combiné l'utilisation du logiciel de simulation LABVIEW et la carte ARDUINO ...

Protease activated receptors (PARS) mediation in gyroxin biological activity; Mediacao dos receptores ativados por proteases (PARs) em atividades biologicas da giroxina

Energy Technology Data Exchange (ETDEWEB)

Silva, Jose Alberto Alves da

2009-07-01

Gyroxin is a serine protease enzyme from the South American rattlesnake (Crotalus durissus terrificus) venom; it is only partially characterized and has multiple activities. Gyroxin induces blood coagulation, blood pressure decrease and a neurotoxic behavior named barrel rotation. The mechanisms involved in this neurotoxic activity are not known. Whereas gyroxin is a member of enzymes with high potential to become a new drug with clinical applications such as thrombin, batroxobin, ancrod, tripsyn and kalicrein, it is important to find out how gyroxin works. The analysis on agarose gel electrophoresis and circular dichroism confirmed the molecules' integrity and purity. The gyroxin intravenous administration in mice proved its neurotoxicity (barrel rotation). In vivo studies employing intravital microscopy proved that gyroxin induces vasodilation with the participation of protease activated receptors (PARs), nitric oxide and Na+K+ATPase. The leukocytes' adherence and rolling counting indicated that gyroxin has no pro inflammatory activity. Gyroxin induced platelet aggregation, which was blocked by inhibitors of PAR1 and PAR4 receptors (SCH 79797 and tcY-NH{sub 2}, respectively). Finally, it was proved that the gyroxin temporarily alter the permeability of the blood brain barrier (BBB). Our study has shown that both the protease-activated receptors and nitric oxide are mediators involved in the biological activities of gyroxin. (author)

Measures and modelling of PAR (photosynthetically-active radiation) for the Northeast of Brazil; Medidas e modelagem da radiacao PAR (photosynthetically-active radiation) para o nordeste do Brasil

Energy Technology Data Exchange (ETDEWEB)

Tiba, Chigueru; Leal, Sergio da S.A. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear], e-mail: tiba@rce.neoline.com.br

2004-07-01

Photosynthetically active solar radiation, known by its acronym in the English language as PAR, is the principal driving force of innumerable biological and physical processes related to biomass production, such as, the evolution of vegetal covering, agricultural productivity, and countless environment aspects, among others. Unfortunately in Brazil and particularly in the Northeast of Brazil, the PAR radiation measures are not a routine part of meteorological station measures, and therefore are still rarer than solar irradiation measures. In this context, a station was installed in Recife, Pernambuco in 2003, to carry out simultaneous measures of daily solar irradiation and PAR irradiation, which permits the modelling and valuation of the relationship between these two parameters and thus makes the estimation of PAR radiation possible, where there used to be only information on solar irradiation. Three others stations are being installed, one on Fernando de Noronha-PE, another in Pesqueira-PE, and the other in Xingo-SE, which complete a group of 4 between Latitudes 8 deg and 10 deg South and Longitudes 34 deg to 38 deg West, each having differentiated Equatorial Climates: island maritime, continental maritime, sylvan (Agreste) and semi-arid. (author)

Soil analyses by ICP-MS (Review)

International Nuclear Information System (INIS)

Yamasaki, Shin-ichi

2000-01-01

Soil analyses by inductively coupled plasma mass spectrometry (ICP-MS) are reviewed. The first half of the paper is devoted to the development of techniques applicable to soil analyses, where diverse analytical parameters are carefully evaluated. However, the choice of soil samples is somewhat arbitrary, and only a limited number of samples (mostly reference materials) are examined. In the second half, efforts are mostly concentrated on the introduction of reports, where a large number of samples and/or very precious samples have been analyzed. Although the analytical techniques used in these reports are not necessarily novel, valuable information concerning such topics as background levels of elements in soils, chemical forms of elements in soils and behavior of elements in soil ecosystems and the environment can be obtained. The major topics discussed are total elemental analysis, analysis of radionuclides with long half-lives, speciation, leaching techniques, and isotope ratio measurements. (author)

A method for estimating the diffuse attenuation coefficient (KdPAR)from paired temperature sensors

Science.gov (United States)

Read, Jordan S.; Rose, Kevin C.; Winslow, Luke A.; Read, Emily K.

2015-01-01

A new method for estimating the diffuse attenuation coefficient for photosynthetically active radiation (KdPAR) from paired temperature sensors was derived. We show that during cases where the attenuation of penetrating shortwave solar radiation is the dominant source of temperature changes, time series measurements of water temperatures at multiple depths (z1 and z2) are related to one another by a linear scaling factor (a). KdPAR can then be estimated by the simple equation KdPAR ln(a)/(z2/z1). A suggested workflow is presented that outlines procedures for calculating KdPAR according to this paired temperature sensor (PTS) method. This method is best suited for conditions when radiative temperature gains are large relative to physical noise. These conditions occur frequently on water bodies with low wind and/or high KdPARs but can be used for other types of lakes during time periods of low wind and/or where spatially redundant measurements of temperatures are available. The optimal vertical placement of temperature sensors according to a priori knowledge of KdPAR is also described. This information can be used to inform the design of future sensor deployments using the PTS method or for campaigns where characterizing sub-daily changes in temperatures is important. The PTS method provides a novel method to characterize light attenuation in aquatic ecosystems without expensive radiometric equipment or the user subjectivity inherent in Secchi depth measurements. This method also can enable the estimation of KdPAR at higher frequencies than many manual monitoring programs allow.

RESOLUTION DU PROBLEME DE PREDICTION LINEAIRE PAR LA METHODE ULV. APPLICATION AU SIGNAL FID

Directory of Open Access Journals (Sweden)

M KHELIF

2003-06-01

Full Text Available Dans le cadre de la spectroscopie RMN, notre objectif est de déterminer le spectre d'absorption du signal de précession libre FID par la méthode de prédiction linéaire (PL. Ceci revient à résoudre le problème de prédiction linéaire en exploitant la méthode de corrélation par l'utilisation de la décomposition en valeurs singulières SVD pour l'inversion de la matrice de corrélation. Or, cette technique est la source d'un certain nombre de problèmes lorsque le signal est noyé dans du bruit. Aussi sera-t-elle coûteuse en temps lorsque les dimensions de la matrice de corrélation sont importantes. Afin de résoudre ce problème, nous exploitons les propriétés d'une nouvelle technique dérivée de la SVD, la décomposition ULV pour minimiser le coût du traitement et assurer une inversion correcte de la matrice de corrélation. Dans ce but, nous déterminons le spectre d'absorption par la technique ULV et nous le comparons avec le spectre déterminé par la SVD et  la FFT. Nous comparons par la suite la qualité des spectres obtenus par rapport au spectre d'absorption idéal  déterminé par FFT.

Comparison of the analytical methods used to determine natural and artificial radionuclides from environmental samples by gamma, alpha and beta spectrometry

DEFF Research Database (Denmark)

Pöllänen, Roy; Virtanen, Sinikka; Kämäräinen, Meerit

In CAMNAR, an extensive interlaboratory exercise on the analytical methods used to determine several radionuclides present in the environmental samples was organized. Activity concentration of different natural radionuclides, such as Rn-222, Pb-210, Po-210, K-40, Ra-226, Ra-228 and isotopes...... of uranium, in addition to artificial Cs-137 and Am-241 were analysed from lake sediment samples and drinking water. The measurement techniques were gamma-ray spectrometry, alpha spectrometry, liquid scintillation counting and inductively coupled plasma mass spectrometry. Twenty six laboratories from nine...

In-situ spectrometry of 137Cs in the soil by unfolding method

International Nuclear Information System (INIS)

Fueloep, M.; Ragan, P.; Krnac, S.

1995-01-01

This contribution is aimed to the possibility of improving the in-situ gamma spectrometry to be independent on a knowledge about a depth distribution of 137 Cs in soil and sufficiently sensitive for the measurement of the post-Chernobyl 137 Cs at present, as well. The depth distribution of 137 Cs averaged over a large area of soil is obtained by unfolding of the detector responses to primary and in soil forward scattered photons. The proposed method employs detector with and without collimator. The 137 Cs distributions obtained in-situ measurements are analysed, and comparisons are made to the results obtained with soil sampling and with standard in-situ spectrometry, as well. 5 figs., 1 tab., 4 refs

Volatile organic compound monitoring by photo acoustic radiometry

International Nuclear Information System (INIS)

Sollid, J.E.; Trujillo, V.L.; Limback, S.P.; Woloshun, K.A.

1995-01-01

Two methods for sampling and analyzing volatile organics in subsurface pore gas were developed for use at the Hazardous Waste Disposal Site at Los Alamos National Laboratory. One is Thermal Desorption Gas Chromatography Mass Spectrometry (TDGCMS), the other is Photoacoustic Radiometry (PAR). Presented here are two years worth of experience and lessons learned as both techniques matured. The sampling technique is equally as important as the analysis method. PAR is a nondispersive infrared technique utilizing band pass filters in the region from 1 to 15 μm. A commercial instrument, the Model 1302 Multigas Analyzer, made by Bruel and Kjaer, was adapted for field use. To use the PAR there must be some a priori knowledge of the constellation of analytes to be measured. The TDGCMS method is sensitive to 50 analytes. Hence TDGCMS is used in an initial survey of the site to determine what compounds are present and at what concentration. Once the major constituents of the soil-gas vapor plume are known the PAR can be configured to monitor for the five analytes of most interest. The PAR can analyse a sample in minutes, while in the field. The PAR is also quite precise in controlled situations

The Determination of Composite Elements in Zircaloy-2 by X-Ray Fluorescence and Emission Spectrometry Method

International Nuclear Information System (INIS)

Dian Anggraini; Rosika Kriswarini; Yusuf N

2007-01-01

Analysis of composing elements in zircaloy-2 has been done by Emission Spectrometry method and X-Ray Fluorescence (XRF). The aim of the analysis is to verify conformity between composing elements in zircaloy-2 and the material certificate. Spectrometry Emission method has higher sensitivity in element determination of a material than that of XRF method, so can be estimated that emission spectrometry method has higher accuracy than that of XRF method. The result of qualitative analysis by Emission Spectrometry indicate that the composing elements in zircaloy-2 were Sn, Cr and Ni. However, the qualitative analysis result by XRF method indicated that the composing elements in zircaloy 2 were Sn, Cr, Ni and Fe. Fe element can not be analysed by Emission Spectrometry method because Emission Spectrometer did not equipped with Fe detector. The quantitative analysis result of the composing elements in the material with both methods showed that Sn, Cr and Ni concentration of zircaloy 2 existed in concentration ranges of the material certificate. Result of statistical test (F and t-test) of analysis result of both methods can be used for analyzing composing elements in zircaloy 2. Emission Spectrometry method was more sensitive and accurate for determining Cr and Ni element in zircaloy 2 than that of emission Spectrometry method but both methods had same accuracy. The precision of measurement of Sn, Cr and Ni element using XRF method was better than that of Emission spectrometry method. (author)

Characterization of Roman glass tesserae from the Coriglia excavation site (Italy) via energy-dispersive X-ray fluorescence spectrometry and Raman spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Donais, Mary Kate; Sparks, Andrew; Redente, Monica [Saint Anselm College, Department of Chemistry, Manchester, NH (United States); Pevenage, Jolien van; Moens, Luc; Vincze, Laszlo [Ghent University, Department of Analytical Chemistry, Ghent (Belgium); George, David B. [Saint Anselm College, Department of Classics, Manchester, NH (United States); Vandenabeele, Peter [Ghent University, Department of Archaeology, Ghent (Belgium)

2016-12-15

The combined use of handheld energy-dispersive X-ray fluorescence spectrometry, Raman spectroscopy, and micro-energy-dispersive X-ray fluorescence spectrometry permitted the characterization of Roman glass tesserae excavation from the Coriglia (Italy) archeological site. Analyses of ten different glass colors were conducted as spot analyses on intact samples and as both spot analyses and line scans on select cross-sectioned samples. The elemental and molecular information gained from these spectral measurements allowed for the qualitative chemical characterization of the bulk glass, decolorants, opacifiers, and coloring agents. The use of an antimony opacifier in many of the samples supports the late Imperial phasing as determined through numismatic, fresco, ceramics, and architectural evidence. And dealinization of the exterior glass layers caused by the burial environment was confirmed. (orig.)

Absolute analysis of uranium isotopic concentrations with a gas ion source mass spectrometer; Analyses absolues des concentrations isotopiques de l'uranium par spectrometre de masse equipe d'une source a gaz

Energy Technology Data Exchange (ETDEWEB)

Chaussy, L.; Boyer, R. [Commissariat a l' Energie Atomique, Pierrelatte (France)

1969-07-01

Mass spectrometer with electronic bombardment ions source for routine uranium isotopic analysis are used like relative measurements apparatus. We show that such mass spectrometers can be used for absolute measurements with a very high sensitivity and precision which are ten times better than theses of thermo-ionic ions source mass spectrometer. We examine the causes of systematic errors and we give experimental data. In particular natural uranium sample used as reference give: U{sub 5} = 0.7202 {+-} 0.0005 atoms per cent; U{sub 4} = 0.00552 {+-} 0.0003 atoms per cent. The use of this method is justified for standards control. (authors) [French] Les spectrometres de masse a source par bombardement electronique pour l'analyse de l'uranium sous forme d'hexafluorure, sont utilises en routine comme des appareils de mesure relative. On montre que l'on peut utiliser de tels appareils pour effectuer des mesures absolues avec une excellente sensibilite et reproductibilite, dix fois superieure a celle des spectrometres a source thermoionique. On examine en detail les causes d'erreurs systematiques et on donne des resultats experimentaux. En particulier, l'analyse d'un echantillon d'uranium naturel donne: U{sub 5} = 0.7202 {+-} 0.0005 atomes pour cent; U{sub 4} = 0.00552 {+-} 0.0003 atomes pour cent. La technique de mesure est utile pour le controle d'etalons isotopiques. (auteurs)

Feasibility of high-resolution continuum source molecular absorption spectrometry in flame and furnace for sulphur determination in petroleum products

Science.gov (United States)

Kowalewska, Zofia

2011-07-01

For the first time, high-resolution molecular absorption spectrometry with a high-intensity xenon lamp as radiation source has been applied for the determination of sulphur in crude oil and petroleum products. The samples were analysed as xylene solutions using vaporisation in acetylene-air flame or in an electrothermally heated graphite furnace. The sensitive rotational lines of the CS molecule, belonging to the ∆ν = 0 vibrational sequence within the electronic transition X 1∑ + → A 1П, were applied. For graphite furnace molecular absorption spectrometry, the Pd + Mg organic modifier was selected. Strong interactions with Pd atoms enable easier decomposition of sulphur-containing compounds, likely through the temporal formation of Pd xS y molecules. At the 258.056 nm line, with the wavelength range covering central pixel ± 5 pixels and with application of interactive background correction, the detection limit was 14 ng in graphite furnace molecular absorption spectrometry and 18 mg kg -1 in flame molecular absorption spectrometry. Meanwhile, application of 2-points background correction found a characteristic mass of 12 ng in graphite furnace molecular absorption spectrometry and a characteristic concentration of 104 mg kg -1 in flame molecular absorption spectrometry. The range of application of the proposed methods turned out to be significantly limited by the properties of the sulphur compounds of interest. In the case of volatile sulphur compounds, which can be present in light petroleum products, severe difficulties were encountered. On the contrary, heavy oils and residues from distillation as well as crude oil could be analysed using both flame and graphite furnace vaporisation. The good accuracy of the proposed methods for these samples was confirmed by their mutual consistency and the results from analysis of reference samples (certified reference materials and home reference materials with sulphur content determined by X-ray fluorescence

Feasibility of high-resolution continuum source molecular absorption spectrometry in flame and furnace for sulphur determination in petroleum products

Energy Technology Data Exchange (ETDEWEB)

Kowalewska, Zofia, E-mail: zofia.kowalewska@obr.pl

2011-07-15

For the first time, high-resolution molecular absorption spectrometry with a high-intensity xenon lamp as radiation source has been applied for the determination of sulphur in crude oil and petroleum products. The samples were analysed as xylene solutions using vaporisation in acetylene-air flame or in an electrothermally heated graphite furnace. The sensitive rotational lines of the CS molecule, belonging to the {Delta}{nu} = 0 vibrational sequence within the electronic transition X{sup 1}{Sigma}{sup +} {yields} A{sup 1}{Pi}, were applied. For graphite furnace molecular absorption spectrometry, the Pd + Mg organic modifier was selected. Strong interactions with Pd atoms enable easier decomposition of sulphur-containing compounds, likely through the temporal formation of Pd{sub x}S{sub y} molecules. At the 258.056 nm line, with the wavelength range covering central pixel {+-} 5 pixels and with application of interactive background correction, the detection limit was 14 ng in graphite furnace molecular absorption spectrometry and 18 mg kg{sup -1} in flame molecular absorption spectrometry. Meanwhile, application of 2-points background correction found a characteristic mass of 12 ng in graphite furnace molecular absorption spectrometry and a characteristic concentration of 104 mg kg{sup -1} in flame molecular absorption spectrometry. The range of application of the proposed methods turned out to be significantly limited by the properties of the sulphur compounds of interest. In the case of volatile sulphur compounds, which can be present in light petroleum products, severe difficulties were encountered. On the contrary, heavy oils and residues from distillation as well as crude oil could be analysed using both flame and graphite furnace vaporisation. The good accuracy of the proposed methods for these samples was confirmed by their mutual consistency and the results from analysis of reference samples (certified reference materials and home reference materials with

A Single-Cell Biochemistry Approach Reveals PAR Complex Dynamics during Cell Polarization.

Science.gov (United States)

Dickinson, Daniel J; Schwager, Francoise; Pintard, Lionel; Gotta, Monica; Goldstein, Bob

2017-08-21

Regulated protein-protein interactions are critical for cell signaling, differentiation, and development. For the study of dynamic regulation of protein interactions in vivo, there is a need for techniques that can yield time-resolved information and probe multiple protein binding partners simultaneously, using small amounts of starting material. Here we describe a single-cell protein interaction assay. Single-cell lysates are generated at defined time points and analyzed using single-molecule pull-down, yielding information about dynamic protein complex regulation in vivo. We established the utility of this approach by studying PAR polarity proteins, which mediate polarization of many animal cell types. We uncovered striking regulation of PAR complex composition and stoichiometry during Caenorhabditis elegans zygote polarization, which takes place in less than 20 min. PAR complex dynamics are linked to the cell cycle by Polo-like kinase 1 and govern the movement of PAR proteins to establish polarity. Our results demonstrate an approach to study dynamic biochemical events in vivo. Copyright © 2017 Elsevier Inc. All rights reserved.

Imaging mass spectrometry statistical analysis.

Science.gov (United States)

Jones, Emrys A; Deininger, Sören-Oliver; Hogendoorn, Pancras C W; Deelder, André M; McDonnell, Liam A

2012-08-30

Imaging mass spectrometry is increasingly used to identify new candidate biomarkers. This clinical application of imaging mass spectrometry is highly multidisciplinary: expertise in mass spectrometry is necessary to acquire high quality data, histology is required to accurately label the origin of each pixel's mass spectrum, disease biology is necessary to understand the potential meaning of the imaging mass spectrometry results, and statistics to assess the confidence of any findings. Imaging mass spectrometry data analysis is further complicated because of the unique nature of the data (within the mass spectrometry field); several of the assumptions implicit in the analysis of LC-MS/profiling datasets are not applicable to imaging. The very large size of imaging datasets and the reporting of many data analysis routines, combined with inadequate training and accessible reviews, have exacerbated this problem. In this paper we provide an accessible review of the nature of imaging data and the different strategies by which the data may be analyzed. Particular attention is paid to the assumptions of the data analysis routines to ensure that the reader is apprised of their correct usage in imaging mass spectrometry research. Copyright © 2012 Elsevier B.V. All rights reserved.

The superoxide scavenger TEMPOL induces urokinase receptor (uPAR expression in human prostate cancer cells

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Francis Joseph

2006-06-01

Full Text Available Abstract There is little understanding of the effect that reactive oxygen metabolites have on cellular behavior during the processes of invasion and metastasis. These oxygen metabolites could interact with a number of targets modulating their function such as enzymes involved in basement membrane dissolution, adhesion molecules involved in motility or receptors involved in proliferation. We investigated the effect of increased scavenging of superoxide anions on the expression of the urokinase receptor (uPAR in PC-3M human prostate cancer cells. Urokinase receptor is a GPI-linked cell surface molecule which mediates multiple functions including adhesion, proliferation and pericellular proteolysis. Addition of the superoxide scavenger 4-hydroxy-2,2,6,6-tetramethylpiperidinyloxy (TEMPOL to PC-3M cultures stimulated expression of uPAR protein peaking between 48 and 72 hours. Cell surface expression of the uPAR was also increased. Surprisingly, uPAR transcript levels increased only slightly and this mild increase did not coincide with the striking degree of protein increase. This disparity indicates that the TEMPOL effect on uPAR occurs through a post-transcriptional mechanism. TEMPOL presence in PC-3M cultures reduced intracellular superoxide-type species by 75% as assayed by NBT dye conversion; however this reduction significantly diminished within hours following TEMPOL removal. The time gap between TEMPOL treatment and peak uPAR protein expression suggests that reduction of reactive oxygen metabolites in prostate cancer cells initiates a multistep pathway which requires several hours to culminate in uPAR induction. These findings reveal a novel pathway for uPAR regulation involving reactive oxygens such as superoxide anion.

Quantitative analysis of strontium 90 in the radioactive wastes by means of thenoyltrifluoroacetone; Dosage du strontium 90 dans les effluents radioactifs par le thenoyltrifluoroacetone

Energy Technology Data Exchange (ETDEWEB)

Testemale, G; Leredde, J L [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1970-07-01

A simple method of analysing the quantity of {sup 90}Sr has been perfected. It consists in a double extraction of it by means of thenoyltrifluoroacetone and tributylphosphate in tetrachloride of carbon followed by eliminating yttrium 90 by means of thenoyltrifluoroacetone in the benzene. Numberings on aliquot parts of wastes make the determination of that element possible. The yield is about 97 per cent. (authors) [French] Une technique simple du dosage du {sup 90}Sr a ete mise au point. Elle consiste en une double extraction par le thenoyltrifluoroacetone et le tributylphosphate dans le tetrachlorure de carbone, suivie de l'elimination de l'yttrium 90 par le thenoyltrifluoroacetone dans le benzene, Des comptages sur des parties aliquotes d'effluents permettent la dermination de cet element. Rendement environ 97 pour cent. (auteurs)

Numerical analysis of the influence of PAR unit elevation within a vessel on its performance

International Nuclear Information System (INIS)

Kotouč, Miroslav

2011-01-01

On the basis of successful validation of the MELCOR code on several experiments from the international OECD/NEA programme THAI, a numerical parametric study has been conducted at NRI Řež evaluating the influence of PAR's vertical position within a vessel on its performance. Simulations were carried out for an Areva PAR unit which was considered to be placed at 5 different elevations in the THAI test vessel, the sixth simulation comprised a model of blower, simulating thus forced convection. The initial conditions were those of the THAI HR-12 test, which was characterized by steam-saturated atmosphere at elevated pressure and temperature. The results show that the overall hydrogen mass recombined monotonically decreases with PAR elevation. This behavior is due to hot, light and hydrogen-lean plume, coming out from the PAR outlet, which, due to buoyancy forces, eventually fills the upper part of the vessel and prevents thus the PAR unit from efficient operation (if the latter is placed near the top). It was also demonstrated that the effect of forced convection is favorable since it breaks the gas stratification and increases thus hydrogen concentration at the PAR inlet. (author)

Increased Soluble Urokinase-Type Plasminogen Activator Receptor (suPAR Levels in Plasma of Suicide Attempters.

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Filip Ventorp

Full Text Available The soluble form of the urokinase receptor, suPAR, has been suggested as a novel biomarker of low-grade inflammation. Activation of the immune system has been proposed to contribute to the development of depression and suicidal behavior. In order to identify depressed and suicidal individuals who could benefit from an anti-inflammatory treatment, a reliable biomarker of low-grade inflammation is vital. This study evaluates plasma suPAR levels as a biomarker of low-grade inflammation in patients with major depressive disorder and in patients who recently attempted suicide. The plasma suPAR and an established biomarker, C reactive protein (CRP of suicide attempters (n = 54, depressed patients (n = 19 and healthy controls (n = 19 was analyzed with enzyme-linked immunosorbent assays. The biomarker attributes of sensitivity and sensibility were evaluated using ROC curve analysis. Both the depressed patients and suicide attempters had increased plasma suPAR. The levels of suPAR discriminated better between controls and suicide attempters than did CRP. In the future, plasma suPAR might be a superior prognosticator regarding outcome of treatment applying conventional antidepressants in conjunction with anti-inflammatory drugs.

Pars plana vitrectomy for disturbing primary vitreous floaters: clinical outcome and patient satisfaction

NARCIS (Netherlands)

Nie, K.F. de; Crama, N.; Tilanus, M.A.D.; Klevering, B.J.; Boon, C.J.F.

2013-01-01

BACKGROUND: Primary vitreous floaters can be highly bothersome in some patients. In the case of persistently bothersome floaters, pars plana vitrectomy may be the most effective treatment. The aim of this study is to evaluate the incidence of complications, and patient satisfaction, after pars plana

Study of inks on paper engravings using portable EDXRF spectrometry

International Nuclear Information System (INIS)

Ferrero, J.L.; Roldan, C.; Juanes, D.; Carballo, J.; Pereira, J.; Ardid, M.; Lluch, J.L.; Vives, R.

2004-01-01

The prints are fragile and delicate art objects that need for its examination a suitable technique for 'in situ', non-destructive and rapid analyses. The energy dispersive X-ray Fluorescence (EDXRF) spectrometry with portable instrumentation offers these analytical properties. In this work we present the EDXRF analyses of eight engravings elaborated with different techniques (etching and heliogravure) from the 17th to 20th centuries. The characterization of the paper is directly done from its EDXRF spectra, whereas the inks are characterized by the ink plus paper analysis after subtracting the background from the paper spectrum. Inorganic components of the paper engravings and inks have been identified from the EDXRF spectra and the results are discussed. Also, we present EDXRF analyses for the identification of inorganic components from six samples of modern inks

Établir un corpus oral de questions : L’analyse semi-automatisée avec Praat et Perl à l’exemple de cinq épisodes de Maya l’Abeille

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Reinhardt Janina

2016-01-01

Full Text Available Cette communication donne des directives pour la sélection des textes ainsi que des propositions concernant l’usage des outils Praat et Perl, puis les applique à un exemple. À l’heure actuelle, le traitement par ordinateur devient de plus en plus important pour l’analyse des corpus. Cependant, l’exploitation de données prêtes à l’usage nous fait parfois oublier qu’un corpus doit tout d’abord être composé de manière adéquate. De plus, l’automatisation peut être très utile, mais il est impératif de l’utiliser uniquement pour ce qui est décidable par les ordinateurs. Par conséquent, la contribution de cet article est une annotation manuelle par Praat, joint à l’application d’un script de Perl exécutant la partie automatisable. Cet article a trois objectifs : supporter et améliorer les recherches s’appuyant sur des corpus, développer une méthodologie pour établir et analyser un corpus de questions parlées, et enfin d’exemplifier une telle procédure à l’aide d’un petit corpus, à savoir cinq épisodes de l’émission télévisée Maya l’Abeille. Dans ce dernier, je démontre que les patrons intonatifs ne peuvent pas être associés directement aux structures morphosyntaxiques. De surcroît, les résultats soutiennent l’idée que la variation morphosyntaxique ne peut pas être expliquée par une seule catégorie de variables (intralinguistiques, extralinguistiques ou discursifs mais par l’ensemble des facteurs appartenant à ces trois catégories.

Active zone proteins are transported via distinct mechanisms regulated by Par-1 kinase.

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Kara R Barber

2017-02-01

Full Text Available Disruption of synapses underlies a plethora of neurodevelopmental and neurodegenerative disease. Presynaptic specialization called the active zone plays a critical role in the communication with postsynaptic neuron. While the role of many proteins at the active zones in synaptic communication is relatively well studied, very little is known about how these proteins are transported to the synapses. For example, are there distinct mechanisms for the transport of active zone components or are they all transported in the same transport vesicle? Is active zone protein transport regulated? In this report we show that overexpression of Par-1/MARK kinase, a protein whose misregulation has been implicated in Autism spectrum disorders (ASDs and neurodegenerative disorders, lead to a specific block in the transport of an active zone protein component- Bruchpilot at Drosophila neuromuscular junctions. Consistent with a block in axonal transport, we find a decrease in number of active zones and reduced neurotransmission in flies overexpressing Par-1 kinase. Interestingly, we find that Par-1 acts independently of Tau-one of the most well studied substrates of Par-1, revealing a presynaptic function for Par-1 that is independent of Tau. Thus, our study strongly suggests that there are distinct mechanisms that transport components of active zones and that they are tightly regulated.

Localization of amylin-like immunoreactivity in melanocyte-stimulating hormone-containing cells of the pars intermedia but not those of the pars distalis in the axolotl (Ambystoma mexicanum) pituitary.

Science.gov (United States)

Suzuki, Hirohumi; Yamamoto, Toshiharu

2016-04-01

Immunohistochemical techniques were employed to investigate the distribution of amylin-like immunoreactivity in the axolotl (Ambystoma mexicanum) pituitary. Amylin-immunoreactive cells were observed in the pars intermedia, and these cells were found to be immunoreactive for α-melanocyte-stimulating hormone (αMSH) as well. In contrast, αMSH-immunoreactive cells in the pars distalis were immuno-negaitive for amylin. These light microscopic findings were confirmed by immunoelectron microscopy. Amylin-immunoreactive signals were located on the haloes of presumable secretory granules in association with αMSH-immunoreactive signals in the amylin-positive cells. However, in the pars distalis, the αMSH-positive cells did not contain amylin-immunoreactive secretory granules. Western blot analysis of axolotl pituitary extracts revealed the labeling of a protein band at approximately 10.5-kDa by the anti-rat amylin serum, which was not labeled by the anti-αMSH antibody. These findings indicate that amylin secreted from MSH-producing cells in the pars intermedia may modulate MSH secretion in an autocrine fashion and may participate in MSH functions such as fatty homeostasis together with MSH. Copyright © 2016 Elsevier GmbH. All rights reserved.

Area specific stripping of lower energy windows for AGS and CGS NaI systems[Airborne Gamma Spectrometry; Carbone Gamma Spectrometry

Energy Technology Data Exchange (ETDEWEB)

Korsbech, U.; Aage, H.K. [Technical Univ. of Denmark (Denmark); Bystroem, S.; Wedmark, M. [Geological Survey of Sweden (Sweden); Thorshaug, S. [Norwegian Radiation Protection Agency (Norway); Bargholz, K. [Danish Emergency Management Agency (Denmark)

2005-05-01

The report describes the results from a NKS (Nordic Nuclear Safety Research) project aiming at examining the possibilities for extracting stripping factors for Airborne Gamma-ray Spectrometry (AGS) data and Carborne Gamma-ray Spectrometry (CGS) data directly from the recorded set of data, i.e. without having to calibrate the detector systems on beforehand. The project 'NKS project ASSb' has been carried out between 1 August 2004 and 31 March 2005 by a research group composed of persons from Technical University of Denmark (DTU), Danish Emergency Management Agency (DEMA), Geological Survey of Sweden (SGU), and Norwegian Radiation Protection Authority (NRPA). The AGS and CGS data sets used for the project were recorded by SGU, DEMA, NGU (Geological Survey of Norway), and SSI (Swedish Radiation Protection Institute). Most of the project effort has been directed towards analysing AGS and CGS data with point source signals recorded at the Barents Rescue 2001 LIVEX exercise at Boden in Sweden. Possibilities and limitations for the method have been identified. (au)

evaluation de la fertilite femelle des arabusta par le niveau de ...

African Journals Online (AJOL)

Les hybrides Arabusta sont caractérisés par une faible fertilité exprimée par des taux de caracolis élevés et des taux de loges vides importants induisant des productivités faibles. Pour une stratégie plus efficiente des sélections, il est important de connaître les niveaux de fertilité femelle des différents types de caféiers ...

Sample Preprocessing For Atomic Spectrometry

International Nuclear Information System (INIS)

Kim, Sun Tae

2004-08-01

This book gives descriptions of atomic spectrometry, which deals with atomic absorption spectrometry such as Maxwell-Boltzmann equation and Beer-Lambert law, atomic absorption spectrometry for solvent extraction, HGAAS, ETASS, and CVAAS and inductively coupled plasma emission spectrometer, such as basic principle, generative principle of plasma and device and equipment, and interferences, and inductively coupled plasma mass spectrometry like device, pros and cons of ICP/MS, sample analysis, reagent, water, acid, flux, materials of experiments, sample and sampling and disassembling of sample and pollution and loss in open system and closed system.

MMP-1/PAR-1 signal transduction axis and its prognostic impact in esophageal squamous cell carcinoma

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Hong-hua Peng

2012-01-01

Full Text Available The matrix metalloprotease-1 (MMP-1/protease-activated receptor-1 (PAR-1 signal transduction axis plays an important role in tumorigenesis. To explore the expression and prognostic value of MMP-1 and PAR-1 in esophageal squamous cell carcinoma (ESCC, we evaluated the expression of two proteins in resected specimens from 85 patients with ESCC by immunohistochemistry. Sixty-two (72.9% and 58 (68.2% tumors were MMP-1- and PAR-1-positive, respectively, while no significant staining was observed in normal esophageal squamous epithelium. MMP-1 and PAR-1 overexpression was significantly associated with tumor node metastasis (TNM stage and regional lymph node involvement. Patients with MMP-1- and PAR-1-positive tumors, respectively, had poorer disease-free survival (DFS than those with negative ESCC (P = 0.002 and 0.003, respectively. Univariate analysis showed a significant relationship between TNM stage [hazard ratio (HR = 2.836, 95% confidence interval (CI = 1.866-4.308], regional lymph node involvement (HR = 2.955, 95%CI = 1.713-5.068, MMP-1 expression (HR = 2.669, 95%CI = 1.229-6.127, and PAR-1 expression (HR = 1.762, 95%CI = 1.156-2.883 and DFS. Multivariate analysis including the above four parameters identified TNM stage (HR = 2.035, 95%CI = 1.167-3.681, MMP-1 expression (HR = 2.109, 95%CI = 1.293-3.279, and PAR-1 expression (HR = 1.967, 95%CI = 1.256-2.881 as independent and significant prognostic factors for DFS. Our data suggest for the first time that MMP-1 and PAR-1 were both overexpressed in ESCC and are novel predictors of poor patient prognosis after curative resection. The MMP-1/PAR-1 signal transduction axis might be a new therapeutic target for future therapies tailored against ESCC.

MMP-1/PAR-1 signal transduction axis and its prognostic impact in esophageal squamous cell carcinoma

Energy Technology Data Exchange (ETDEWEB)

Peng, Hong-hua; Zhang, Xi; Cao, Pei-guo [Department of Oncology, the Third Xiangya Hospital, Central South University, Changsha, Hunan Province (China)

2011-11-18

The matrix metalloprotease-1 (MMP-1)/protease-activated receptor-1 (PAR-1) signal transduction axis plays an important role in tumorigenesis. To explore the expression and prognostic value of MMP-1 and PAR-1 in esophageal squamous cell carcinoma (ESCC), we evaluated the expression of two proteins in resected specimens from 85 patients with ESCC by immunohistochemistry. Sixty-two (72.9%) and 58 (68.2%) tumors were MMP-1- and PAR-1-positive, respectively, while no significant staining was observed in normal esophageal squamous epithelium. MMP-1 and PAR-1 overexpression was significantly associated with tumor node metastasis (TNM) stage and regional lymph node involvement. Patients with MMP-1- and PAR-1-positive tumors, respectively, had poorer disease-free survival (DFS) than those with negative ESCC (P = 0.002 and 0.003, respectively). Univariate analysis showed a significant relationship between TNM stage [hazard ratio (HR) = 2.836, 95% confidence interval (CI) = 1.866-4.308], regional lymph node involvement (HR = 2.955, 95%CI = 1.713-5.068), MMP-1 expression (HR = 2.669, 95%CI = 1.229-6.127), and PAR-1 expression (HR = 1.762, 95%CI = 1.156-2.883) and DFS. Multivariate analysis including the above four parameters identified TNM stage (HR = 2.035, 95%CI = 1.167-3.681), MMP-1 expression (HR = 2.109, 95%CI = 1.293-3.279), and PAR-1 expression (HR = 1.967, 95%CI = 1.256-2.881) as independent and significant prognostic factors for DFS. Our data suggest for the first time that MMP-1 and PAR-1 were both overexpressed in ESCC and are novel predictors of poor patient prognosis after curative resection. The MMP-1/PAR-1 signal transduction axis might be a new therapeutic target for future therapies tailored against ESCC.

Radiological findings and healing patterns of incomplete stress fractures of the pars interarticularis

International Nuclear Information System (INIS)

Dunn, Andrew J.; Campbell, Robert S.D.; Mayor, Peter E.; Rees, Dai

2008-01-01

The objective was to retrospectively record the CT and MRI features and healing patterns of acute, incomplete stress fractures of the pars interarticularis. The CT scans of 156 adolescents referred with suspected pars interarticularis stress fractures were reviewed. Patients with incomplete (grade 2) pars fractures were included in the study. Fractures were assessed on CT according to vertebral level, location of cortical involvement and direction of fracture propagation. MRI was also performed in 72 of the 156 cases. MRI images of incomplete fractures were assessed for the presence of marrow oedema and cortical integrity. Fracture healing patterns were characterised on follow-up CT imaging. Twenty-five incomplete fractures were identified in 23 patients on CT. All fractures involved the inferior or infero-medial cortex of the pars and propagated superiorly or superolaterally. Ninety-two percent of incomplete fractures demonstrated either complete or partial healing on follow-up imaging. Two (8%) cases progressed to complete fractures. Thirteen incomplete fractures in 11 patients confirmed on CT also had MRI, and 92% demonstrated oedema in the pars. Ten out of thirteen fractures (77%) showed a break in the infero-medial cortex with intact supero-lateral cortex, which correlated with the CT findings. MRI incorrectly graded one case as a complete (grade 3) fracture, and 2 cases as (grade 1) stress reaction. Six fractures had follow-up MRI, 67% showed partial or complete cortical healing, and the same number showed persistent marrow oedema. Incomplete fracture of the pars interarticularis represents a stage of the evolution of a complete stress fracture. The direction of fracture propagation is consistent, and complete healing can be achieved in most cases with appropriate clinical management. CT best demonstrates fracture size and extent, and is the most appropriate modality for follow-up. MRI is limited in its ability to fully depict the cortical integrity of

Radiological findings and healing patterns of incomplete stress fractures of the pars interarticularis

Energy Technology Data Exchange (ETDEWEB)

Dunn, Andrew J.; Campbell, Robert S.D. [Royal Liverpool and Broadgreen University Teaching Hospitals, Department of Medical Imaging, Liverpool (United Kingdom); Mayor, Peter E. [Leighton Hospital, Department of Medical Imaging, Crewe, Cheshire (United Kingdom); Rees, Dai [Robert Jones and Agnes-Hunt Orthopaedic Hospital, Department of Orthopaedic Surgery, Oswestry, Shropshire (United Kingdom)

2008-05-15

The objective was to retrospectively record the CT and MRI features and healing patterns of acute, incomplete stress fractures of the pars interarticularis. The CT scans of 156 adolescents referred with suspected pars interarticularis stress fractures were reviewed. Patients with incomplete (grade 2) pars fractures were included in the study. Fractures were assessed on CT according to vertebral level, location of cortical involvement and direction of fracture propagation. MRI was also performed in 72 of the 156 cases. MRI images of incomplete fractures were assessed for the presence of marrow oedema and cortical integrity. Fracture healing patterns were characterised on follow-up CT imaging. Twenty-five incomplete fractures were identified in 23 patients on CT. All fractures involved the inferior or infero-medial cortex of the pars and propagated superiorly or superolaterally. Ninety-two percent of incomplete fractures demonstrated either complete or partial healing on follow-up imaging. Two (8%) cases progressed to complete fractures. Thirteen incomplete fractures in 11 patients confirmed on CT also had MRI, and 92% demonstrated oedema in the pars. Ten out of thirteen fractures (77%) showed a break in the infero-medial cortex with intact supero-lateral cortex, which correlated with the CT findings. MRI incorrectly graded one case as a complete (grade 3) fracture, and 2 cases as (grade 1) stress reaction. Six fractures had follow-up MRI, 67% showed partial or complete cortical healing, and the same number showed persistent marrow oedema. Incomplete fracture of the pars interarticularis represents a stage of the evolution of a complete stress fracture. The direction of fracture propagation is consistent, and complete healing can be achieved in most cases with appropriate clinical management. CT best demonstrates fracture size and extent, and is the most appropriate modality for follow-up. MRI is limited in its ability to fully depict the cortical integrity of

Equações de chuvas intensas para o estado do Pará Intense rainfall equations for the state of Pará, Brazil

Directory of Open Access Journals (Sweden)

Rodrigo O. R. de M. Souza

2012-09-01

Full Text Available As equações de chuvas intensas têm sido usadas como ferramenta importante para o dimensionamento de obras hidráulicas. Devido à grande carência de informações relativas às equações de chuvas intensas, o presente trabalho teve como objetivo a obtenção das relações de intensidade, duração e frequência de precipitação pluvial para o Estado do Pará, utilizando-se a metodologia da desagregação da chuva de 24 h. Foram utilizadas séries históricas de dados pluviométricos de 74 cidades do Estado do Pará, obtidas no Sistema de Informações Hidrológicas da Agência Nacional de Águas-ANA. As equações de intensidade-duração-frequência foram devidamente ajustadas e apresentaram bom ajuste, com coeficientes de determinação acima de 0,99. A maioria das estações (51,4% apresentou intensidade de precipitação entre 90 e 110 mm h-1, para uma duração de chuva de 30 min e um tempo de retorno de 15 anos. Pode-se perceber uma concentração das maiores precipitações na região próxima ao litoral do nordeste paraense e no sudeste da Ilha do Marajó.The intense rainfall equations have been used as an important tool for design of hydraulic structures. Considering the lack of intense rainfall equations, this study aimed to determine the relations of intensity, duration and frequency of intense rainfall in the Pará State (Brazil, using the one-day rain disaggregation method. In this research rainfall data of 74 cities in the State of Pará were used, obtained from the Hydrological Information System of the National Water Agency-ANA. The equations of intensity-duration-frequency were adjusted and presented good adjustment with coefficients of determination above 0.99. Most stations (51.4% showed intensity of precipitation between 90 and 110 mm h-1 for duration of 30 min and rainfall return period of 15 years. The highest rainfall intensities were in the region near the northeast coast of Pará State and southeast of the Marajo

Heavy ion recoil spectrometry of SixGe1-x thin films

International Nuclear Information System (INIS)

Walker, S.R.; Johnston, P.N.; Bubb, I.F.; Cohen, D.D.; Dytlewski, N.; Hult, M.; Whitlow, H.J.; Zaring, C.; Oestling, M.

1993-01-01

Mass and energy dispersive recoil spectrometry employing 77 MeV 127 I ions from ANTARES (FN Tandem) facility at Lucas Heights has been used to examine the isotopic composition of samples of Si x Ge 1-x grown at the Australian National University by Electron Beam Evaporation (EBE). The recoiling target nuclei were analysed by a Time Of Flight and Energy (TOF-E) detector telescope composed of two timing pickoff detectors and a surface barrier (energy) detector. From the time of flight and energy, the ion mass can be determined and individual depth distributions for each element can be obtained. Recoil spectrometry has shown the presence of oxygen in the Si x Ge 1-x layer and has enabled the separate determination of energy spectra for individual elements. 9 refs., 3 figs

Software for nuclear spectrometry

International Nuclear Information System (INIS)

1998-10-01

The Advisory Group Meeting (AGM) on Software for Nuclear Spectrometry was dedicated to review the present status of software for nuclear spectrometry and to advise on future activities in this field. Because similar AGM and consultant's meetings had been held in the past; together with an attempt to get more streamlined, this AGM was devoted to the specific field of software for gamma ray spectrometry. Nevertheless, many of the issues discussed and the recommendations made are of general concern for any software on nuclear spectrometry. The report is organized by sections. The 'Summary' gives conclusions and recommendations adopted at the AGM. These conclusions and recommendations resulted from the discussions held during and after presentations of the scientific and technical papers. These papers are reported here in their integral form in the following Sections

Plant-derived SAC domain of PAR-4 (Prostate Apoptosis Response 4 exhibits growth inhibitory effects in prostate cancer cells

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Shayan eSarkar

2015-10-01

Full Text Available The gene Par-4 (Prostate Apoptosis Response 4 was originally identified in prostate cancer cells undergoing apoptosis and its product Par-4 showed cancer specific pro-apoptotic activity. Particularly, the SAC domain of Par-4 (SAC-Par-4 selectively kills cancer cells leaving normal cells unaffected. The therapeutic significance of bioactive SAC-Par-4 is enormous in cancer biology; however, its large scale production is still a matter of concern. Here we report the production of SAC-Par-4-GFP fusion protein coupled to translational enhancer sequence (5′ AMV and apoplast signal peptide (aTP in transgenic Nicotiana tabacum cv. Samsun NN plants under the control of a unique recombinant promoter M24. Transgene integration was confirmed by genomic DNA PCR, Southern and Northern blotting, Real-time PCR and Nuclear run-on assays. Results of Western blot analysis and ELISA confirmed expression of recombinant SAC-Par-4-GFP protein and it was as high as 0.15% of total soluble protein. In addition, we found that targeting of plant recombinant SAC-Par-4-GFP to the apoplast and endoplasmic reticulum (ER was essential for the stability of plant recombinant protein in comparison to the bacterial derived SAC-Par-4. Deglycosylation analysis demonstrated that ER-targeted SAC-Par-4-GFP-SEKDEL undergoes O-linked glycosylation unlike apoplast-targeted SAC-Par-4-GFP. Furthermore, various in vitro studies like mammalian cells proliferation assay (MTT, apoptosis induction assays, and NF-κB suppression suggested the cytotoxic and apoptotic properties of plant-derived SAC-Par-4-GFP against multiple prostate cancer cell lines. Additionally, pre-treatment of MAT-LyLu prostate cancer cells with purified SAC-Par-4-GFP significantly delayed the onset of tumor in a syngeneic rat prostate cancer model. Taken altogether, we proclaim that plant made SAC-Par-4 may become a useful alternate therapy for effectively alleviating cancer in the new era.

Acrylamide levels in Finnish foodstuffs analysed with liquid chromatography tandem mass spectrometry.

Science.gov (United States)

Eerola, Susanna; Hollebekkers, Koen; Hallikainen, Anja; Peltonen, Kimmo

2007-02-01

Sample clean-up and HPLC with tandem mass spectrometric detection (LC-MS/MS) was validated for the routine analysis of acrylamide in various foodstuffs. The method used proved to be reliable and the detection limit for routine monitoring was sensitive enough for foods and drinks (38 microg/kg for foods and 5 microg/L for drinks). The RSDs for repeatability and day-to-day variation were below 15% in all food matrices. Two hundred and one samples which included more than 30 different types of food and foods manufactured and prepared in various ways were analysed. The main types of food analysed were potato and cereal-based foods, processed foods (pizza, minced beef meat, meat balls, chicken nuggets, potato-ham casserole and fried bacon) and coffee. Acrylamide was detected at levels, ranging from nondetectable to 1480 microg/kg level in solid food, with crisp bread exhibiting the highest levels. In drinks, the highest value (29 microg/L) was found in regular coffee drinks.

Hep par-1: a novel immunohistochemical marker for differentiating hepatocellular carcinoma from metastatic carcinoma

International Nuclear Information System (INIS)

Hanif, R.

2014-01-01

To evaluate the diagnostic utility of Hep par-1 in differentiating hepatocellular carcinoma from metastatic carcinoma taking histopathology as a gold standard. Study Design: Comparative cross-sectional study. Place and Duration of Study: Pathology Department, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, from April 2007 to February 2008. Methodology: Hep par-1 immunohistochemical stain was performed on 60 cases of liver carcinoma, 30 cases each of metastatic and hepatocellular carcinoma. Information regarding patient age, gender, sign and symptoms, radiographic findings, histological grade of tumour, and expression of Hep par-1 on hepatocellular and metastatic carcinoma were recorded on proforma sheet. Sensitivity, specificity, positive and negative predictive values, and accuracy of Hep par-1 were calculated using the formulas. Results: Hep par-1 expression was noted in 25 out of 30 cases of hepatocellular carcinoma (83%). Out of 30 cases of metastatic carcinoma, only one case expressed staining in < 5% tumour cells and remaining 29 cases showed no reactivity. The age of the patients with hepatocellular carcinoma ranged from 40 to 76 years with a median age of 60.5 years and 40 - 75 years for metastatic carcinomas with a median age of 57.5 years. Conclusion: Hep par-1 is a reliable immunohistochemical marker for cases of hepatocellular carcinoma (HCC). It can be used along with other markers in morphologically difficult cases when differential diagnosis lies between poorly differentiated HCC and metastatic carcinoma of liver. (author)

Technique du Micro-Enseignement: Une Approche Pour Enseigner La Pratique de La Lecture aux Apprenants de Niveau A2 et La Perception de Cette Technique Par Les Futurs Enseignants

Directory of Open Access Journals (Sweden)

Nurten ÖZÇELİK

2017-09-01

Full Text Available Cette étude a été préparée en vue de déterminer les difficultés rencontrées par les futurs enseignants lors de l’enseignement de la lecture aux apprenants de niveau A2 par la technique du micro-enseignement, et de mettre à jour leurs opinions concernant les avantages ainsi que les inconvénients de cette technique. Le groupe de travail est composé de 20 futurs enseignants (14 femmes, 6 hommes du Département de la Didactique du FLE de la Faculté Pédagogique de l’Université Gazi, pour le deuxième semestre de la période 2014-2015. Les données recueillies par les questions à réponses ouvertes ont été évaluées par la méthode de l’analyse descriptive, à la suite des calculs de fréquence. Selon les résultats obtenus, les futurs enseignants ont surtout du mal à prononcer le français, à gérer leurs émotions, à préparer une présentation, des activités de pré-lecture et du dossier de présentation. Augmenter la confiance en soi, apprendre à préparer un plan de cours, donner la possibilité de voir les aspects insuffisants sont les points positifs de la technique. L’insuffisance des participations au cours, l’artificialité du milieu de la classe, la subjectivité des critiques des pairs sont indiqués par les participants comme les inconvénients de cette technique.

Paraplégie compliquant une plaie abdominale antérieure par arme blanche

Science.gov (United States)

Elahmadi, Brahim; Awab, Almahdi; El Moussaoui, Rachid; El Hijri, Ahmed; Azzouzi, Abderrahim; Alilou, Mustapha

2015-01-01

Les traumatismes médullaires sont des complications rares des plaies abdominales antérieures par arme blanche. Son diagnostic est difficile parfois retardé. L'imagerie par résonance magnétique reste l'examen de choix. Le traitement dépend du tableau clinique et de la gravité de la souffrance médullaire. Le pronostic est corrélé à l’étendue et à la nature de la lésion médullaire. Nous rapportons un cas exceptionnel d'un traumatisme médullaire chez une patiente victime d'une plaie abdominale antérieure par arme blanche. PMID:25995808

In vitro activity of five quinolones and analysis of the quinolone resistance-determining regions of gyrA, gyrB, parC, and parE in Ureaplasma parvum and Ureaplasma urealyticum clinical isolates from perinatal patients in Japan.

Science.gov (United States)

Kawai, Yasuhiro; Nakura, Yukiko; Wakimoto, Tetsu; Nomiyama, Makoto; Tokuda, Tsugumichi; Takayanagi, Toshimitsu; Shiraishi, Jun; Wasada, Kenshi; Kitajima, Hiroyuki; Fujita, Tomio; Nakayama, Masahiro; Mitsuda, Nobuaki; Nakanishi, Isao; Takeuchi, Makoto; Yanagihara, Itaru

2015-04-01

Ureaplasma spp. cause several disorders, such as nongonococcal urethritis, miscarriage, and preterm delivery with lung infections in neonates, characterized by pathological chorioamnionitis in the placenta. Although reports on antibiotic resistance in Ureaplasma are on the rise, reports on quinolone-resistant Ureaplasma infections in Japan are limited. The purpose of this study was to determine susceptibilities to five quinolones of Ureaplasma urealyticum and Ureaplasma parvum isolated from perinatal samples in Japan and to characterize the quinolone resistance-determining regions in the gyrA, gyrB, parC, and parE genes. Out of 28 clinical Ureaplasma strains, we isolated 9 with high MICs of quinolones and found a single parC gene mutation, resulting in the change S83L. Among 158 samples, the ParC S83L mutation was found in 37 samples (23.4%), including 1 sample harboring a ParC S83L-GyrB P462S double mutant. Novel mutations of ureaplasmal ParC (S83W and S84P) were independently found in one of the samples. Homology modeling of the ParC S83W mutant suggested steric hindrance of the quinolone-binding pocket (QBP), and de novo prediction of peptide structures revealed that the ParC S84P may break/kink the formation of the α4 helix in the QBP. Further investigations are required to unravel the extent and mechanism of antibiotic resistance of Ureaplasma spp. in Japan. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Diagnosing impaired glucose tolerance using direct infusion mass spectrometry of blood plasma.

Directory of Open Access Journals (Sweden)

Petr G Lokhov

Full Text Available The goal of this study was to evaluate the capacity for mass spectrometry of blood plasma to diagnose impaired glucose tolerance (IGT. For this study, blood plasma samples from control subjects (n = 30 and patients with IGT (n = 20 were treated with methanol and low molecular weight fraction were then analyzed by direct infusion mass spectrometry. A total of 51 metabolite ions strongly associated with IGT were detected. The area under a receiver operating characteristic (ROC curve (AUC for diagnosing IGT that was based on an analysis of all these metabolites was 0.93 (accuracy 90%, specificity 90%, and sensitivity 90%. The associated reproducibility was 85%. The metabolites identified were also consistent with risk factors previously associated with the development of diabetes. Thus, direct infusion mass spectrometry of blood plasma metabolites represents a rapid, single-step, and reproducible method for the analysis of metabolites. Moreover, this method has the potential to serve as a prototype for clinical analyses that could replace the currently used glucose tolerance test with a more patient-friendly assay.

Use of 1012 ohm current amplifiers in Sr and Nd isotope analyses by TIMS for application to sub-nanogram samples

NARCIS (Netherlands)

Koornneef, J.M.; Bouman, C.; Schwieters, J.B.; Davies, G.R.

2013-01-01

We have investigated the use of current amplifiers equipped with 10 12 ohm feedback resistors in thermal ionisation mass spectrometry (TIMS) analyses of sub-nanogram sample aliquots for Nd and Sr isotope ratios. The results of analyses using the 1012 ohm resistors were compared to those obtained

Determination of {sup 126}Sn half-life from ICP-MS and gamma spectrometry measurements

Energy Technology Data Exchange (ETDEWEB)

Bienvenu, P.; Arnal, N.; Comte, J. [CEA Cadarache DEN/DEC/SA3C/LARC, Paul Lez Durance (France); Ferreux, L.; Lepy, M.C.; Be, M.M. [CEA Saclay LIST LNE/LNHB, Gif sur Yvette (France); Andreoletti, G. [AREVA Cogema SL/UP2-800, Beaumont Hague (France)

2009-07-01

A new value of {sup 126}Sn half-life was determined by combination of inductively coupled plasma-mass spectrometry (ICP-MS) and gamma spectrometry measurements on purified sample solutions collected from nuclear fuel reprocessing. {sup 126}Sn was isolated through dissolution of fission product precipitates and liquid-liquid extraction with N-benzoyl-N-phenyl-hydroxylamine (BPHA). The abundance of {sup 126}Sn atoms together with the absence of interfering species in the analysed solutions made it possible to measure both mass concentration and nuclide activity with high precision and accuracy. This led to a {sup 126}Sn half-life value of 1.980 (57) x 10{sup 5} a. (orig.)

Increased plasma soluble uPAR level is a risk marker of respiratory cancer in initially cancer-free individuals

DEFF Research Database (Denmark)

Langkilde, Anne A; Hansen, Tine Willum; Ladelund, Steen

2011-01-01

BACKGROUND: Soluble urokinase plasminogen activator receptor (suPAR) is a stable plasma biomarker associated with inflammation and disease. This study tested the association between suPAR levels and incident respiratory, gastrointestinal or other types of cancer in initially cancer-free individuals...... with respiratory, gastrointestinal and other cancer types, respectively.CONCLUSIONS: Elevated suPAR levels were associated with increased risk of incident respiratory cancer and other types of cancer, but not gastrointestinal cancers, independently of established risk factors, CRP and leukocyte numbers. Impact.......RESULTS: suPAR levels ranged from 0.6-22 ng/ml, and median suPAR level was 4.01 ng/ml. 1 ng/ml increase in baseline suPAR was associated with adjusted hazard ratios (HR) of 1.61 (95% CI: 1.23-2.11, P

Lambeaux autofermants pour le traitement des brulures electriques du scalp par haut voltage

Science.gov (United States)

Hafidi, J.; El Mazouz, S.; El Mejatti, H.; Fejjal, N.; Gharib, N.E.; Abbassi, A.; Belmahi, A.M.

2011-01-01

Summary Les brûlures électriques par haut voltage sont responsables de gros dégâts tissulaires en immédiat et dans les jours suivant l’accident du fait de la chaleur importante dégagée par effet joule et de la thrombose microvasculaire évolutive. Les pertes de substances du scalp secondaires à ces brûlures nécessitent une couverture par lambeaux vu la destruction du périoste et du calvarium en regard. De juin 1997 à juin 2008, 15 patients ont été traités pour des pertes de substance du scalp secondaires à des brûlures électriques par haut voltage de diamètre allant de 8 à 11 cm et siégeant dans la région tonsurale. Ces patients ont été opérés dans la première semaine suivant l’accident. Les pertes de substance du scalp de taille moyenne secondaires à ces brûlures peuvent être couvertes per primam de façon fiable par des lambeaux locaux axialisés et multiples. Nous relatons l’expérience du Service de Chirurgie Plastique du Centre Hospitalier Universitaire Ibn-Sina, Rabat, Maroc, dans la gestion et la prise en charge de ces brûlures. PMID:22262963

Spondylolysis outcomes in adolescents after direct screw repair of the pars interarticularis.

Science.gov (United States)

Snyder, Laura A; Shufflebarger, Harry; O'Brien, Michael F; Thind, Harjot; Theodore, Nicholas; Kakarla, Udaya K

2014-09-01

Isthmic spondylolysis can significantly decrease functional abilities, especially in adolescent athletes. Although treatment can range from observation to surgery, direct screw placement through the fractured pars, or Buck's procedure, may be a more minimally invasive procedure than the more common pedicle screw-hook construct. Review of surgical databases identified 16 consecutive patients treated with Buck's procedure from 2004 to 2010. Twelve patients were treated at Miami Children's Hospital and 4 at Barrow Neurological Institute. Demographics and clinical and radiographic outcomes were recorded and analyzed retrospectively. The 16 patients had a median age of 16 years, and 14 were 20 years or younger at the time of treatment. Symptoms included axial back pain in 100% of patients with concomitant radiculopathy in 38%. Pars defects were bilateral in 81% and unilateral in 19% for a total of 29 pars defects treated using Buck's procedure. Autograft or allograft augmented with recombinant human bone morphogenetic protein as well as postoperative bracing was used in all cases. Postoperatively, symptoms resolved completely or partially in 15 patients (94%). Of 29 pars defects, healing was observed in 26 (89.6%) prior to 1 revision surgery, and an overall fusion rate of 97% was observed at last radiological follow-up. There were no implant failures. All 8 athletes in this group had returned to play at last follow-up. Direct screw repair of the pars interarticularis defect as described in this series may provide a more minimally invasive treatment of adolescent patients with satisfactory clinical and radiological outcomes, including return to play of adolescent athletes.

Compression robuste du signal par la transformée avec les B ...

African Journals Online (AJOL)

Par contre, elle diminue de façon considérable pour les b-splincs et les paquets dbndelcttes de Haar. Du point de vue entropie, la compression par bfsplines est bonne que celle de la TCD. Nous donnons ci-dessous un tableau récapitulatif des résultats de quelques méthodes utilisées pour deux signaux EMG. Le facteur de ...

Planar Cell Polarity Breaks the Symmetry of PAR Protein Distribution prior to Mitosis in Drosophila Sensory Organ Precursor Cells.

Science.gov (United States)

Besson, Charlotte; Bernard, Fred; Corson, Francis; Rouault, Hervé; Reynaud, Elodie; Keder, Alyona; Mazouni, Khalil; Schweisguth, François

2015-04-20

During development, cell-fate diversity can result from the unequal segregation of fate determinants at mitosis. Polarization of the mother cell is essential for asymmetric cell division (ACD). It often involves the formation of a cortical domain containing the PAR complex proteins Par3, Par6, and atypical protein kinase C (aPKC). In the fly notum, sensory organ precursor cells (SOPs) divide asymmetrically within the plane of the epithelium and along the body axis to generate two distinct cells. Fate asymmetry depends on the asymmetric localization of the PAR complex. In the absence of planar cell polarity (PCP), SOPs divide with a random planar orientation but still asymmetrically, showing that PCP is dispensable for PAR asymmetry at mitosis. To study when and how the PAR complex localizes asymmetrically, we have used a quantitative imaging approach to measure the planar polarization of the proteins Bazooka (Baz, fly Par3), Par6, and aPKC in living pupae. By using imaging of functional GFP-tagged proteins with image processing and computational modeling, we find that Baz, Par6, and aPKC become planar polarized prior to mitosis in a manner independent of the AuroraA kinase and that PCP is required for the planar polarization of Baz, Par6, and aPKC during interphase. This indicates that a "mitosis rescue" mechanism establishes asymmetry at mitosis in PCP mutants. This study therefore identifies PCP as the initial symmetry-breaking signal for the planar polarization of PAR proteins in asymmetrically dividing SOPs. Copyright © 2015 Elsevier Ltd. All rights reserved.

uPAR EXPRESSION IN CANINE NORMAL PROSTATE AND WITH PROLIFERATIVE DISORDERS

Directory of Open Access Journals (Sweden)

Mariana Rodrigues Faleiro

2013-06-01

Full Text Available Prostatic lesions such as prostatic intraepithelial neoplasia (PIN and proliferative inflammatory atrophy (PIA are studied in human and canine species due to their malignance potential. The plasminogen activator (PA system has been suggested to play a central role in cell adhesion, angiogenesis, inflammation, and tumor invasion. The urokinase-type plasminogen activator receptor (uPAR is a component of the PA, with a range of expression in tumor and stromal cells. In this study, uPAR expression in both canine normal prostates and with proliferative disorders (benign prostatic hyperplasia-BPH, proliferative inflammatory atrophy-PIA, prostatic intraepithelial neoplasia-PIN, and carcinoma-PC was evaluated by immunohistochemistry in a tissue microarray (TMA slide to establish the role of this enzyme in extracellular matrix (ECM remodeling and in the processes of tissue invasion. A total of 298 cores and 355 diagnoses were obtained, with 36 (10.1% normal prostates, 46 (13.0% with BPH, 128 (36.1% with PIA, 74 (20.8% with PIN and 71 (20.0% with PC. There is variation in the expression of uPAR in canine prostate according to the lesion, with lower expression in normal tissue and with BPH, and higher expression in tissue with PIA, PIN and PC. The high expression of uPAR in inflammatory and neoplastic microenvironment indicates increased proteolytic activity in canine prostates with PIA, PIN, and PC.

Evaluation of metal and radionuclide data from neutron activation and acid-digestion-based spectrometry analyses of background soils: Significance in environmental restoration

Energy Technology Data Exchange (ETDEWEB)

Lee, S.Y.; Watkins, D.R.; Jackson, B.L.; Schmoyer, R.L. [Oak Ridge National Lab., TN (United States); Lietzke, D.A.; Burgoa, B.B.; Branson, J.T.; Ammons, J.T. [Univ. of Tennessee, Knoxville, TN (United States)

1995-12-31

A faster, more cost-effective, and higher-quality data acquisition procedure for natural background-level metals and radionuclides in soils is needed for remedial investigations of contaminated sites. In this project, a total of 120 soil samples were collected from uncontaminated areas on and near the Oak Ridge Reservation. The samples were taken at three different depths and from three different geologic groups to establish background concentrations of metals and radionuclides. The objective of this presentation is to discuss the advantages and disadvantages of neutron activation analysis (NAA) compared with those of acid-digestion-based spectrometry (ADS) methods; the advantages and disadvantages were evaluated from Al, Sb, As, Cr, Co, Fe, Mg, Mn, Hg, K, Ag, {sup 232}Th, {sup 235}U, {sup 238}U, V, and Zn data. The ADS methods used for this project were inductively coupled plasma (ICP), ICP-mass spectrometry (ICP-MS), and alpha spectrometry. The scatter plots showed that the NAA results for As, Co, Fe, Mn, {sup 232}Th, and {sup 238}U are reasonably correlated with the results from the other analytical methods. Compared to NAA, however, the ADS methods underestimated Al, Cr, Mg, K, V, and Zn. The skew distributions were caused by incomplete dissolution of the analytes during acid digestion of the soil samples. Because of the high detection limits of the spectrometric methods, the NAA results and the ADS results for some elements, including Sb, Hg, and Ag, did not show a definite relationship. The NAA results were highly correlated with the alpha spectrometry results for {sup 232}Th and {sup 238}U but poorly correlated for {sup 235}U, probably because of a larger counting error associated with the lower activity of the isotope. The NAA methods, including the delayed neutron counting method, were far superior techniques for quantifying background levels of radionuclides ({sup 232}Th, {sup 235}U, and {sup 238}U) and metals (Al, Cr, Mg, K, V, and Zn) in soils.

Evaluation of metal and radionuclide data from neutron activation and acid-digestion-based spectrometry analyses of background soils: Significance in environmental restoration

International Nuclear Information System (INIS)

Lee, S.Y.; Watkins, D.R.; Jackson, B.L.; Schmoyer, R.L.; Lietzke, D.A.; Burgoa, B.B.; Branson, J.T.; Ammons, J.T.

1995-01-01

A faster, more cost-effective, and higher-quality data acquisition procedure for natural background-level metals and radionuclides in soils is needed for remedial investigations of contaminated sites. In this project, a total of 120 soil samples were collected from uncontaminated areas on and near the Oak Ridge Reservation. The samples were taken at three different depths and from three different geologic groups to establish background concentrations of metals and radionuclides. The objective of this presentation is to discuss the advantages and disadvantages of neutron activation analysis (NAA) compared with those of acid-digestion-based spectrometry (ADS) methods; the advantages and disadvantages were evaluated from Al, Sb, As, Cr, Co, Fe, Mg, Mn, Hg, K, Ag, 232 Th, 235 U, 238 U, V, and Zn data. The ADS methods used for this project were inductively coupled plasma (ICP), ICP-mass spectrometry (ICP-MS), and alpha spectrometry. The scatter plots showed that the NAA results for As, Co, Fe, Mn, 232 Th, and 238 U are reasonably correlated with the results from the other analytical methods. Compared to NAA, however, the ADS methods underestimated Al, Cr, Mg, K, V, and Zn. The skew distributions were caused by incomplete dissolution of the analytes during acid digestion of the soil samples. Because of the high detection limits of the spectrometric methods, the NAA results and the ADS results for some elements, including Sb, Hg, and Ag, did not show a definite relationship. The NAA results were highly correlated with the alpha spectrometry results for 232 Th and 238 U but poorly correlated for 235 U, probably because of a larger counting error associated with the lower activity of the isotope. The NAA methods, including the delayed neutron counting method, were far superior techniques for quantifying background levels of radionuclides ( 232 Th, 235 U, and 238 U) and metals (Al, Cr, Mg, K, V, and Zn) in soils

In vitro and in vivo inhibition of proangiogenic retinal phenotype by an antisense oligonucleotide downregulating uPAR expression.

Science.gov (United States)

Lulli, Matteo; Cammalleri, Maurizio; Granucci, Irene; Witort, Ewa; Bono, Silvia; Di Gesualdo, Federico; Lupia, Antonella; Loffredo, Rosa; Casini, Giovanni; Dal Monte, Massimo; Capaccioli, Sergio

2017-08-26

Neoangiogenesis is the main pathogenic event involved in a variety of retinal diseases. It has been recently demonstrated that inhibiting the urokinase-type plasminogen activator receptor (uPAR) results in reduced angiogenesis in a mouse model of oxygen-induced retinopathy (OIR), establishing uPAR as a therapeutic target in proliferative retinopathies. Here, we evaluated in cultured human retinal endothelial cells (HRECs) and in OIR mice the potential of a specific antisense oligodeoxyribonucleotide (ASO) in blocking the synthesis of uPAR and in providing antiangiogenic effects. uPAR expression in HRECs was inhibited by lipofection with the phosphorotioated 5'-CGGCGGGTGACCCATGTG-3' ASO-uPAR, complementary to the initial translation site of uPAR mRNA. Inhibition of uPAR expression via ASO-uPAR was evaluated in HRECs by analyzing VEGF-induced tube formation and migration. In addition, the well-established and reproducible murine OIR model was used to induce retinal neovascularization in vivo. OIR mice were injected intraperitoneally with ASO-uPAR and retinopathy was evaluated considering the extent of the avascular area in the central retina and neovascular tuft formation. The ASO-uPAR specifically decreased uPAR mRNA and protein levels in HRECs and mitigated VEGF-induced tube formation and cell migration. Noteworthy, in OIR mice ASO-uPAR administration reduced both the avascular area and the formation of neovascular tufts. In conclusion, although the extrapolation of these experimental findings to the clinic is not straightforward, ASO-uPAR may be considered a potential therapeutic tool for treatment of proliferative retinal diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

Protease activated receptors (PARS) mediation in gyroxin biological activity

International Nuclear Information System (INIS)

Silva, Jose Alberto Alves da

2009-01-01

Gyroxin is a serine protease enzyme from the South American rattlesnake (Crotalus durissus terrificus) venom; it is only partially characterized and has multiple activities. Gyroxin induces blood coagulation, blood pressure decrease and a neurotoxic behavior named barrel rotation. The mechanisms involved in this neurotoxic activity are not known. Whereas gyroxin is a member of enzymes with high potential to become a new drug with clinical applications such as thrombin, batroxobin, ancrod, tripsyn and kalicrein, it is important to find out how gyroxin works. The analysis on agarose gel electrophoresis and circular dichroism confirmed the molecules' integrity and purity. The gyroxin intravenous administration in mice proved its neurotoxicity (barrel rotation). In vivo studies employing intravital microscopy proved that gyroxin induces vasodilation with the participation of protease activated receptors (PARs), nitric oxide and Na+K+ATPase. The leukocytes' adherence and rolling counting indicated that gyroxin has no pro inflammatory activity. Gyroxin induced platelet aggregation, which was blocked by inhibitors of PAR1 and PAR4 receptors (SCH 79797 and tcY-NH 2 , respectively). Finally, it was proved that the gyroxin temporarily alter the permeability of the blood brain barrier (BBB). Our study has shown that both the protease-activated receptors and nitric oxide are mediators involved in the biological activities of gyroxin. (author)

Localizing by autoradiography at -195 deg radioactive areas in rats exposed to a high flux of thermal neutrons, importance of phosphorus 32 in consecutive internal irradiation; Localisation par autoradiographie a -195 deg des zones radioactives chez le rat expose a un haut flux de neutrons thermiques, importance du phosphore 32 dans l'irradiation interne consecutive

Energy Technology Data Exchange (ETDEWEB)

Chanteur, J; Pellerin, P [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1961-07-01

Rats weighing 25 g were exposed for 5 mn to a flux of 6.10{sup 12} thermal neutrons/cm{sup 2}/s. Anatomical autoradiography at -195 deg. C has enabled the radioactive organs to be easily localised, to follow in course of time the decrease of radioactivity, and from it to deduce the probable nature of the numerous emitters in question. In particular, the phosphorus 32 has thus appeared to be one of those responsible for internal irradiation, general, on the one hand, by activating cellular phosphorus, local, on the other, by activating bony phosphates. Owing to this, an accidental irradiation by neutrons might have consequences that are both somatic (elective irradiation of the bone marrow) and genetic (activation of nucleic acids). The gamma spectrometry has confirmed the nature of certain other emitters. (author) [French] Des rats de 25 g ont ete exposes pendant 5 mn a un flux de 6.10{sup 12} neutrons thermiques/cm{sup 2}/s. L'autoradiographie anatomique a -195 deg. C a permis de localiser facilement les organes radioactifs, de suivre dans le temps la decroissance de la radioactivite, et d'en deduire la nature probable des nombreux emetteurs en cause. En particulier, le phosphore 32 est ainsi apparu comme l'un des responsables de l'irradiation interne, d'une part generale par activation du phosphore cellulaire, d'autre part locale par activation des phosphates osseux. Une irradiations accidentelle par neutrons aurait, de ce fait, des consequences a la fois somatiques (irradiation elective de la moelle osseuse) et genetiques (activation des acides nucleiques). La spectrometrie gamma a confirme la nature de certains autres emetteurs. (auteur)

Flame emission, atomic absorption and fluorescence spectrometry

International Nuclear Information System (INIS)

Horlick, G.

1980-01-01

Six hundred and thirty references are cited in this review. The information in the review is divided into 12 major areas: books, reviews, and bibliographies; fundamental studies in flames; developments in instrumentation; measurement techniques and procedure; flame emission spectrometry; flame atomic absorption spectrometry; flame molecular absorption spectrometry; electrothermal atomization atomic absorption spectroscopy; hydride generation techniques; graphite furnace atomic emission spectrometry; atomic fluorescence spectrometry; and analytical comparisons

Avis 6 sur la formation à et par la recherche

OpenAIRE

Centre de Coopération Internationale en Recherche Agronomique pour le Développement

2015-01-01

La formation à et par la recherche s’appuie sur la démarche scientifique, les savoirs, les connaissances à transmettre, tout autant que l’acquisition de compétences en gestion de projet, de capacités au travail en équipe, d’une ouverture d’esprit qui favorisera la créativité. Elle doit permettre de prendre conscience de la responsabilité endossée par la communauté scientifique vis-à-vis de la société et de l’environnement, mais aussi préparer l’avenir professionnel de celle ou de celui qu...

Désadification biologique des vins par les levures de fleur

Directory of Open Access Journals (Sweden)

C. LLAGUNO

1971-03-01

Le processus de désacidification bactérienne du vin par la fermentation malolactique est bien connu. Le vin acquiert ainsi une plus grande souplesse au goût et une stabilité biologique indispensable à sa conservation en bouteilles. Cependant, les levures Schizosaccharomyces pombe peuvent aussi fermenter l'acide malique (RIBÉREAU-GAYON et PEYNAUD, 1962. TARANTOLA et GANDINI, 1967 ont décrit des essais semi-industriels de désacidification biologique d'un moût blanc piémontais ; provoquée aussi bien par l'ensemencement de bactéries malolactiques  que de Schizosaccharomyces pombe.

Preparation and study of the properties of lead telluride and cadmium telluride diodes for use in nuclear spectrometry; Preparation et etude des proprietes de diodes au tellurure de plomb et au tellurure de cadmium en vue d'une utilisation en spectrometrie nucleaire

Energy Technology Data Exchange (ETDEWEB)

Lancon, R [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1969-07-01

This work studies the possibility of using high atomic number compound semiconductors, like lead telluride and cadmium telluride as to realize nuclear radiation detectors, specially in gamma ray spectrometry because of their high absorption coefficient. The problems related to the preparation of binary compounds are exposed. Experiments on PbTe show the influence of the conditions of preparation on the electrical properties of the semiconductor which are greatly dependent on the stoichiometry of the compound. PbTe surface-barrier diodes were realized and have been used to study the surface properties of this semiconductor. These diodes cannot detect nuclear radiations because of the too weak resistivity of our material. Different types of devices made of Cd Te have been studied. One of these diodes has been used as an alpha particle detector. We explain the relative poor performances of that detector by the presence of lattice defects in Cd Te where charge carriers may recombine themselves. By analysing the properties of gold diffused Cd Te diodes we identified this defect, the cadmium vacancy, the presence of which is due to the deviation from stoichiometry during the preparation of the material. (author) [French] Ce travail etudie la possibilite d'utiliser des semiconducteurs composes d'elements a numero atomique eleve, tels que le tellurure de plomb et le tellurure de cadmium pour la realisation de detecteurs de rayonnements nucleaires, grace notamment a la section efficace de capture elevee qu'ils presentent vis-a-vis des rayons gamma. On souligne les problemes relatifs a la preparation des composes binaires. Les experiences realisees sur PbTe mettent en evidence l'influence des conditions de preparation sur les proprietes electriques du semiconducteur qui dependent fortement de la stoechiometrie du compose. Nous avons realise des diodes au PbTe a barriere de surface qui ont permis de preciser les proprietes de surface de ce semiconducteur. La trop faible

Structure identification by Mass Spectrometry Non-Targeted Analysis using the US EPA’s CompTox Chemistry Dashboard

Science.gov (United States)

Identification of unknowns in mass spectrometry based non-targeted analyses (NTA) requires the integration of complementary pieces of data to arrive at a confident, consensus structure. Researchers use chemical reference databases, spectral matching, fragment prediction tools, r...

"Parīzes šiks" mūsdienu restorānu interjera dizainā

OpenAIRE

Kalnarāja, Agnese

2015-01-01

Diplomdarbā “Parīzes šiks mūsdienu restorānu interjera dizainā” sastāv no piecām nodaļām. Pirmajā nodaļā tiek aprakstīta Parīzes arhitektūras un interjera dizaina vēsture, tā ietekme uz “Parīzes šika” veidošanos, kā arī pētīta restorānu vēsture. Otrajā nodaļā tiek pētīti elementi, kas raksturo “Parīzes šika” interjeru. Trešajā nodaļā tiek analizēti un aprakstīti psiholoģiskie faktori, kas ietekmē restorānu dizainu – apgaismojums, krāsu lietojums un atmosfēras nozīme interjerā. Empīriskajā...

Mass spectrometry in clinical chemistry

International Nuclear Information System (INIS)

Pettersen, J.E.

1977-01-01

A brief description is given of the functional elements of a mass spectrometer and of some currently employed mass spectrometric techniques, such as combined gas chromatography-mass spectrometry, mass chromatography, and selected ion monitoring. Various areas of application of mass spectrometry in clinical chemistry are discussed, such as inborn errors of metabolism and other metabolic disorders, intoxications, quantitative determinations of drugs, hormones, gases, and trace elements, and the use of isotope dilution mass spectrometry as a definitive method for the establishment of true values for concentrations of various compounds in reference sera. It is concluded that mass spectrometry is of great value in clinical chemistry. (Auth.)

Analysis of oak tannins by liquid chromatography-electrospray ionisation mass spectrometry.

Science.gov (United States)

Mämmelä, P; Savolainen, H; Lindroos, L; Kangas, J; Vartiainen, T

2000-09-01

Extractable tannins were analysed by liquid chromatography-electrospray ionisation mass spectrometry in two oak species, North American white oak (Quercus alba) and European red oak (Quercus robur). They mainly included various glucose gallic and ellagic acid esters. The structures were partially determined, and they included grandinin/roburin E, castalagin/vescalagin, gallic acid, valoneic acid bilactone, monogalloyl glucose, digalloyl glucose, trigalloyl glucose, ellagic acid rhamnose, quercitrin and ellagic acid.

Funding Research Through the Online Partnership to Accelerate Research (OnPAR

Directory of Open Access Journals (Sweden)

Martin A. Dueñas, MPA

2016-10-01

Full Text Available OnPAR—the Online Partnership to Accelerate Research—seeks to provide a second opportunity for funding of high-quality, unfunded applications originally submitted to the National Institutes of Health and other national and international funding agencies. OnPAR will match applicable, unfunded applications with the research priorities of nongovernment organizations such as private biomedical foundations, pharmaceutical companies, venture capital funds, and other private funds. Funding organization members will review and make final funding decisions through a simple, 2-step process whereby applicants can submit public abstracts directly to OnPAR. If a member requests additional information, then, by invitation only, an applicant can submit their original unfunded application and their peer review summary statement. Advancing research discovery and drug development to improve clinical outcomes for patients afflicted with or at risk for disease is the primary goal of OnPAR. OnPAR invites the scientific community to fully participate in this new funding paradigm by submitting their National Institutes of Health public abstracts so that funding members can review and potentially support these high-quality, unfunded applications.

Automation on computers of the partial area method for the analysis of 's' neutron induced resonances. I. Without interference terms. (1962); Automatisation sur ordinateur de la methode des aires partielle dans l'analyse des resonances induites par les neutrons 's'. I. sans terme d'interference. (1962)

Energy Technology Data Exchange (ETDEWEB)

Bianchi, G; Corge, C R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1962-07-01

This report deals with numerical analysis of transmission resonances induced by 's' wave neutrons in time of flight experiments. The analysis method used is the partial area one. The only case treated here, in this first part, is the one when the interference term can be neglected. Programs and subroutines are thoroughly described, which determine from experimental raw data the resonant transmission, the partial areas, and the resonance parameters. (authors) [French] Le present rapport a pour objet l'analyse numerique sur ordinateur IBM 7090, des resonances dues aux neutrons 's' dans les experiences de transmission par temps de vol, la methode d'analyse utilisee etant la methode des aires partielles. Dans cette premiere partie, seul a ete envisage le cas ou le terme d'interference peut etre neglige. On y trouvera une description detaillee des programmes et sous programmes elabores pour determiner les transmissions resonantes avec leur trace, a partir des donnees experimentales brutes, les aires partielles afferentes ainsi que les parametres caracteristiques des resonances. (auteurs)

Eleventh ISMAS workshop on mass spectrometry

International Nuclear Information System (INIS)

Aggarwal, S.K.; Jaison, P.G.

2004-10-01

This volume deals with the latest developments in this field, exposing the innumerable applications of mass spectrometry. The topics covered include basic fundamentals of mass spectrometry, qualitative and quantitative aspects and data interpretation, maintenance of mass spectrometers, selection of a mass spectrometer, its applications in various branches of science as well as recent advances in mass spectrometry. Emphasis is also laid on the practical aspects of mass spectrometry. Papers relevant to INIS are indexed separately

Factor Xa stimulates fibroblast procollagen production, proliferation, and calcium signaling via PAR1 activation

International Nuclear Information System (INIS)

Blanc-Brude, Olivier P.; Archer, Fabienne; Leoni, Patricia; Derian, Claudia; Bolsover, Steven; Laurent, Geoffrey J.; Chambers, Rachel C.

2005-01-01

Fibroblast proliferation and procollagen production are central features of tissue repair and fibrosis. In addition to its role in blood clotting, the coagulation cascade proteinase thrombin can contribute to tissue repair by stimulating fibroblasts via proteolytic activation of proteinase-activated receptor-1 (PAR 1 ). During hemostasis, the coagulation cascade proteinase factor X is converted into factor Xa. We have previously shown that factor Xa upregulates fibroblast proliferation via production of autocrine PDGF. In this study, we further examined the effects of factor Xa on fibroblast function and aimed to identify its signaling receptor. We showed that factor Xa stimulates procollagen promoter activity and protein production by human and mouse fibroblasts. This effect was independent of PDGF and thrombin production, but dependent on factor Xa proteolytic activity. We also showed that PAR 1 -deficient mouse fibroblasts did not upregulate procollagen production, mobilize cytosolic calcium, or proliferate in response to factor Xa. Desensitization techniques and PAR 1 -specific agonists and inhibitors were used to demonstrate that PAR 1 mediates factor Xa signaling in human fibroblasts. This is the first report that factor Xa stimulates extracellular matrix production. In contrast with endothelial cells and vascular smooth muscle cells, fibroblasts appear to be the only cell type in which the effects of factor Xa are mediated mainly via PAR 1 and not PAR 2 . These findings are critical for our understanding of tissue repair and fibrotic mechanisms, and for the design of novel approaches to inhibit the profibrotic effects of the coagulation cascade without compromising blood hemostasis

Recherche documentaire par titrage automatique

OpenAIRE

Lopez , Cédric; Prince , Violaine; Roche , Mathieu

2011-01-01

Nous proposons dans cet article un système facilitant la recherche d'information dans un ensemble de documents textuels, basé sur le titrage (et sous-titrage) automatique. Ce dernier peut se révéler crucial, par exemple, dans le cadre de la problématique de l'accessibilité des pages web (norme W3C). Notre processus de titrage automatique consiste à extraire des syntagmes nominaux pertinents dans les textes, pouvant constituer des titres ou sous-titres candidats. Une approche originale combina...

Mass spectrometry and tandem mass spectrometry of citrus limonoids.

Science.gov (United States)

Tian, Qingguo; Schwartz, Steven J

2003-10-15

Methods for atmospheric pressure chemical ionization tandem mass spectrometry (APCI-MS/MS) of citrus limonoid aglycones and electrospray ionization tandem mass spectrometry (ESI-MS/MS) of limonoid glucosides are reported. The fragmentation patterns of four citrus limonoid aglycones (limonin, nomilin, obacunone, and deacetylnomilin) and six limonoid glucosides, that is, limonin 17-beta-D-glucopyranoside (LG), nomilin 17-beta-D-glucopyranoside (NG), nomilinic acid 17-beta-D-glucopyranoside (NAG), deacetyl nomilinic acid 17-beta-D-glucopyranoside (DNAG), obacunone 17-beta-D-glucopyranoside (OG), and obacunoic acid 17-beta-D-glucopyranoside (OAG) were investigated using a quadruple mass spectrometer in low-energy collisionally activated dissociation (CAD). The four limonoid aglycones and four limonoid glucosides (LG, OG, NAG, and DNAG) were purified from citrus seeds; the other two limonoid glucosides (NG and OAG) were tentatively identified in the crude extract of grapefruit seeds by ESI mass spectrometry in both positive and negative ion analysis. Ammonium hydroxide or acetic acid was added to the mobile phase to facilitate ionization. During positive ion APCI analysis of limonoid aglycones, protonated molecular ion, [M + H]+, or adduct ion, [M + NH3 + H]-, was formed as base peaks when ammonium hydroxide was added to the mobile phase. Molecular anions or adduct ions with acetic acid ([M + HOAc - H] and [M + HOAc]-) or a deprotonated molecular ion were produced during negative ion APCI analysis of limonoid aglycones, depending on the mobile-phase modifier used. Positive ion ESI-MS of limonoid glucosides produced adduct ions of [M + H + NH3]+, [M + Na]+, and [M + K]+ when ammonium hydroxide was added to the mobile phase. After collisionally activated dissociation (CAD) of the limonoid aglycone molecular ions in negative ion APCI analysis, fragment ions indicated structural information of the precursor ions, showing the presence of methyl, carboxyl, and oxygenated ring

Liquid chromatography-mass spectrometry coupling by the intermediary of a liquid micro chromatography-electro spray interface; Couplage chromatographie liquide-spectrometrie de masse par l`intermediaire d`une interface electrospray-microchromatographie liquide

Energy Technology Data Exchange (ETDEWEB)

Gillard Factor, C

1996-12-06

The objective of this work is to realize a liquid chromatography- mass spectrometry coupling by the intermediary of an electro spray interface and the evaluation of performances of tis analytical tool to study pollutants in water, and more particularly pesticides whom maximum admissible concentration in a table water is 0.1{mu}g/l. This study has allowed to bring to the fore the interest of the ionization mode by electro spray in a LC/MS coupling to identify and quantify pesticides in the state of traces without treating the sample. Then, it was demonstrated the usefulness of this analytical tool to detect high molecular masses molecules. (N.C.)

Urokinase-type plasminogen activator receptor (uPAR) as a promising new imaging target

DEFF Research Database (Denmark)

Persson, Morten; Kjaer, Andreas

2013-01-01

modalities such as optical imaging, magnetic resonance imaging, single photon emission computer tomography (SPECT) and positron emission topography (PET). In this review, we will discuss recent advances in the development of uPAR-targeted imaging ligands according to imaging modality. In addition, we...... will discuss the potential future clinical application for uPAR imaging as a new imaging biomarker....

Contribution to the determination of Sb-Ag-Cu-Ga-Mo-Zn using 14 MeV neutron activation; Contribution au dosage de Sb-Ag-Cu-Ga-Mo-Zn par activation aux neutrons de 14 MeV

Energy Technology Data Exchange (ETDEWEB)

Crambes, M [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1966-04-01

By using, 14 MeV, neutron irradiation it is possible to extend the field of application of neutron radio-activation analysis, in particular to the case of light elements. For, many other elements it can replace in-pile irradiation thereby making it possible, thanks to portable 14 MeV neutron generators, to carry out radio-activation analyses away from nuclear-research c e n t r e s. With a view to applying this analytical technique to routine work, we have developed some rapid chemical separation methods in order to make possible the determination of several elements which after exposure to fast neutrons, produce {beta} emitting nuclides which cannot be differentiated by a simple instrumental study, the emitted radiation being of the same type and of similar half-life the two cases. (author) [French] L'irradiation au moyen de neutrons de 14 MeV permet d'etendre le domaine d'application de l'analyse par radioactivation neutronique, en particulier aux elements legers. Cependant pour de nombreux autres elements elle peut remplacer l'irradiation en reacteur nucleaire permettant ainsi grace aux ensembles portables producteurs de neutrons de 14 MeV, l'extension de l'analyse par radioactivation a l'exterieur des centres d'etudes nucleaires. Dans le but d'appliquer cette methode d'analyse a des travaux de routine, nous avons mis au point des separations chimiques rapides, afin de permettre le dosage de quelques elements qui par irradiation aux neutrons rapides, engendrent des nucleides emetteurs {beta} qu'une simple etude instrumentale ne peut differencier en raison de l'identite de leur rayonnement et de leurs periodes radioactives trop proches. (auteur)

Protease-activated receptor 2 (PAR2) is upregulated by Acanthamoeba plasminogen activator (aPA) and induces proinflammatory cytokine in human corneal epithelial cells.

Science.gov (United States)

Tripathi, Trivendra; Abdi, Mahshid; Alizadeh, Hassan

2014-05-29

Acanthamoeba plasminogen activator (aPA) is a serine protease elaborated by Acanthamoeba trophozoites that facilitates the invasion of trophozoites to the host and contributes to the pathogenesis of Acanthamoeba keratitis (AK). The aim of this study was to explore if aPA stimulates proinflammatory cytokine in human corneal epithelial (HCE) cells via the protease-activated receptors (PARs) pathway. Acanthamoeba castellanii trophozoites were grown in peptone-yeast extract glucose for 7 days, and the supernatants were collected and centrifuged. The aPA was purified using the fast protein liquid chromatography system, and aPA activity was determined by zymography assays. Human corneal epithelial cells were incubated with or without aPA (100 μg/mL), PAR1 agonists (thrombin, 10 μM; TRAP-6, 10 μM), and PAR2 agonists (SLIGRL-NH2, 100 μM; AC 55541, 10 μM) for 24 and 48 hours. Inhibition of PAR1 and PAR2 involved preincubating the HCE cells for 1 hour with the antagonist of PAR1 (SCH 79797, 60 μM) and PAR2 (FSLLRY-NH2, 100 μM) with or without aPA. Human corneal epithelial cells also were preincubated with PAR1 and PAR2 antagonists and then incubated with or without PAR1 agonists (thrombin and TRAP-6) and PAR2 agonists (SLIGRL-NH2 and AC 55541). Expression of PAR1 and PAR2 was examined by quantitative RT-PCR (qRT-PCR), flow cytometry, and immunocytochemistry. Interleukin-8 expression was quantified by qRT-PCR and ELISA. Human corneal epithelial cells constitutively expressed PAR1 and PAR2 mRNA. Acanthamoeba plasminogen activator and PAR2 agonists significantly upregulated PAR2 mRNA expression (1- and 2-fold, respectively) (P aPA, and PAR2 agonists induced PAR2 mRNA expression in HCE cells (P aPA, significantly upregulated PAR1 mRNA expression, which was significantly inhibited by PAR1 antagonist in HCE cells. Acanthamoeba plasminogen activator and PAR2 agonists stimulated IL-8 mRNA expression and protein production, which is significantly diminished by PAR2 antagonist