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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Mediální skandalizace sexuálních afér v církvi v českém tisku na jaře 2010 / Medial muck-raking of sexual affairs in fold in czech press in spring 2010

Šulcová, Jana January 2011 (has links)
The thesis "Medial muck-raking of sexual affairs in the Church in Czech press in spring 2010" through the use of medial ruts, stereotypes and logic, inquires into medial texts from the springtime 2010, which have referenced to sexual affairs in Catholic Church. Based on medial theories (gatekeeping, social construction of reality, agenda setting etc.) the thesis follows up the reflection of the theme and specifics of media discourse. This view is complemented with interviews with members of the Church, which give the thesis out-of- media extent. Qualitative part of the thesis takes sexual affairs in Church as illustrative theme, which is meant in connection with the Roman Catholic Church reflected by Czech media. The thesis also attempts to generalize the actual medial reflection of the Church on the background of current medial trends. It tries to offer a way how to improve the relationship between two part of culture - media and the Roman Catholic Church. To put the thesis into context it will be provided with information about history of the Roman Catolic Church and relationship of Czech society to matters of the church, because it determinates perception of medial news about this theme.
242

Strukturuntersuchungen an Proteinen der bakteriellen Stressantwort: NblA von Anabaena sp. PCC 7120 und Csp:ssDNA-Komplexe von Bacillus caldolyticus und Bacillus subtilis

Bienert, Ralf 11 December 2006 (has links)
Die meisten Cyanobakterien und Chloroplasten von Rotalgen verfügen über Phycobilisomen, große lichtsammelnde Multiproteinkomplexe, die an der cytoplasmatischen Seite der Thylakoidmembran gebunden vorliegen. Unter stickstofflimitierten Bedingungen werden die Phycobilisomen proteolytisch abgebaut. Dieser Prozess schützt vor Fotoschäden unter den gegebenen Stressbedingungen und liefert gleichzeitig einen großen Vorrat an Stickstoff enthaltenden Substanzen. Das Gen nblA, welches in allen Phycobilisomen enthaltenden Organismen vorkommt, kodiert für ein Polypeptid von ungefähr 7 kDa, das eine Schlüsselrolle im Abbau der Phycobilisomen einnimmt. Die Wirkungsweise von NblA dabei wird jedoch bisher kaum verstanden. Ein Selenomethioninderivat von NblA des filamentösen Cyanobakteriums Anabaena sp. PCC 7120 wurde in Escherichia coli rekombinant hergestellt, gereinigt und kristallisiert. Die Röntgenkristallstruktur von NblA wurde mithilfe der single-wavelength anomalous dispersion-Methode bis zu einer Auflösung von 1,8 Angstrom bestimmt. Das finale Modell verfügt über einen kristallographischen R-Wert von 18,2% und einen freien R-Wert von 21,7%. Das kleine NblA-Protein von 65 Aminosäuren besteht aus zwei alpha-Helices, die in einem ca. 37°-Winkel in einer antiparallelen, V-förmigen Anordnung zueinander stehen. Zwei dieser Monomere bilden die grundlegende strukturelle Einheit von NblA, ein vier-Helix-Bündel, bei dem sich die Spitzen der "Vs" auf der gleichen Seite des Dimers überlagern und über eine nicht-kristallographische zweizählige Achse miteinander verknüpft sind. Auf der Grundlage von Bindungsstudien und der Kenntnis der NblA-Struktur konnte ein Modell für die Bindung von NblA an die Phycobilisomenstruktur postuliert werden. / Cyanobacterial light harvesting complexes, the phycobilisomes, are proteolytically degraded when the organisms are starved for combined nitrogen, a process referred to as chlorosis or bleaching. Gene nblA, present in all phycobilisome-containing organisms, encodes a protein of about 7 kDa that plays a key role in phycobilisome degradation. To gain deeper insights into the mode of action of NblA in this degradation process the crystal structure of NblA was determined and a model of its binding to phycobilisomes was proposed. For this purpose, NblA from Anabaena sp. PCC 7120 was produced as selenomethionine NblA derivative in Escherichia coli B834 (DE3), purified and crystalized. NblA crystals grew as long, but thin rods and belong to the monoclinic space group P2(1) with cell parameters of a = 43.2 A, b = 95.9 A, c = 104.8 A and Beta = 97.0°. They contain twelve NblA monomers in the asymmetric unit. The crystal structure with a resolution of 1.8 A was determined using the single-wavelength anomalous dispersion (SAD) technique and refined to final values for Rwork and Rfree of 0.182 and 0.217, respectively. The small NblA polypeptide of 65 amino acids consists of two alpha-helices which are assembled at a ~37° angle in an antiparallel, V-shaped arrangement. Two NblA monomers form the basic structural unit of NblA, a four-helix bundle with the tips of the V superimposing on the same side of a dimer. The dimer is formed by two molecules related by a non-crystallographic dyad axis. Based on the crystal structure presented here, pull-down experiments, and peptide scan data a model of binding of NblA to phycobilisomes was proposed. Considering the entire phycobilisome structure, NblA is predicted to bind via its amino acids Leu51 and Lys53 to the trimer-trimer interface of the phycobiliprotein hexamers.
243

Dynamique de formation et de déformation de minibassins en contexte compressif : exemple du bassin de Sivas, Turquie Approche terrain et implications structurales multiéchelles / Evolution of minibasins in compressive setting. The case of the Sivas Basin, Turkey

Kergaravat, Charlie 30 March 2016 (has links)
Cette thèse porte sur les interactions entre les déformations halocinétiques locales au sein des mini-bassins salifères et les déformations régionales compressives. L’étude s’appuie sur une analyse structurale multi-échelle détaillée d’une province à mini-bassins se développant dans le bassin d’avant pays de Sivas (Turquie). Une analyse de terrain approfondie, associée à une étude de données de subsurface, permet de proposer une révision des cartes géologiques ainsi qu’une évolution tectonosédimentaire identifiant les déformations liées à la tectonique salifère et celles liées à la propagation de la ceinture de plis et de chevauchements dans l’avant-pays. A partir de l’Eocène supérieur, le fluage del’évaporite autochtone, initié et entretenu par le chargement sédimentaire différentiel ainsi que par la déformation compressive, permet la formation d’une première génération de mini-bassins. Ces minibassins, constitués par une formation continentale Oligocène, vont être recouverts par une nappe d’évaporite allochtone accueillant une seconde génération de mini-bassins constitués de formations continentales et marines Oligo-Miocène. L’initiation du domaine de mini-bassins secondaires est caractérisée par une distribution polygonale du réseau de diapirs et de murs d’évaporites. Ces mini-bassins enregistrent localement les effets de la tectonique salifère par le développement d’une grande variété de structures halocinétiques à différentes échelles telles que les séquences halocinétiques unitaires (crochet et éventail), séquences composites (tabulaire ou fuseau) et megaflaps. Une série de modélisation analogique préliminaire amontré que ces structures peuvent se développer avec ou sans l’application d’une compression aux limites. De plus, les analogies géométriques entre les mini-bassins de Sivas et les provinces salifères connues suggèrent que la dynamique de formation de ces mini-bassins est au premier ordre contrôlée par le chargement sédimentaire différentiel, découplé partiellement de la compression régionale. Néanmoins, l’analyse du réseau de fractures et de l’endommagement matriciel souligne l’enregistrement précoce de la déformation compressive régionale lors de l’initiation des mini-bassins.L’influence du raccourcissement sur la structuration de la province à mini-bassins s’exprime de manière croissante par l’écrasement des corps salifères permettant : (i) le développement de dépocentres linéaires préférentiellement perpendiculaire à la direction de raccourcissement, (ii) l’émergence de corps allochtones d’évaporites en surface, ainsi que (iii) la rotation et translation des mini-bassins. Cette province à mini-bassins génère une discontinuité dans la propagation et l’accommodation de la déformation compressive : la déformation compressive est accommodée auniveau du réseau polygonal de murs d’évaporites formant des structures multidirectionnelles. De plus, cette concentration de la déformation par écrasement des structures salifères entraine la remobilisation des évaporites vers l’avant-pays générant alors un nouveau système salifère. / This doctoral work studies the interaction between withdrawal of minibasins and regional shortening during evolution of a foreland fold-and-thrust belt. This is achieved by a multiscale structural analysis of the Sivas Basin (Turkey). Extensive field work and regional seismic lines interpretations helped to build a new and detailed geologic map of the central Sivas Basin and to provide a new tectonosedimentary framework highlighting the influence of salt tectonics and the regional shortening, starting in the Late Eocene by the autochthonous evaporite deposition. This level is remobilized by the northward migrating sedimentary load, shortening and tilting of the basin southern margin during propagation of the foreland fold-and-thrust belt. Evaporite flow is recorded by the withdrawal of a primary generation of continental Oligocene minibasins which are then covered by an evaporite canopy. The canopy extending northward allows the development of second generation of continental to shallow marine mini-basins from Oligocene to Middle Miocene. Secondary minibasins initiation in the central part of the Basin, is characterized by sub-circular minibasins surrounded by polygonal diapirs and walls. Flanking these minibasins, a large variety of halokinetic structures is described: halokinetic sequences (hooks and wedges), composite halokinetic sequences and megaflaps. Preliminary sand-box modeling study suggests the development of thesehalokinetic structures both with and without shortening. Furthermore, minibasins geometries are closely similar to those imaged or mapped in other salt provinces suggesting that mini-basin withdrew is first control by sedimentary load, probably due to decoupling by the salt. However, the fractures and anisotropy of magnetic susceptibility analyses suggests the record of shortening since the minibasins initiation. The increase influence of regional shortening on the minibasins domain is expressed by salt walls and diapirs squeezing inducing: (i) the development of linear mini-basins perpendicular to the shortening direction, (ii) salt sheet emplacement and (iii) the translation/rotation of minibasins. The minibasins province produces a discontinuity for the fold-and-thrust belt propagation. Indeed, the minibasins province accommodates the shortening deformation along the polygonal network of salt walls and diapirs forming multidirectional structures. Furthermore, the regional shortening accommodation by salt structures squeezing produce an evaporitic remobilization and migration of a salt canopy toward the foreland basin. / Bu doktora tezi/çalışması, bir önülke kıvrım ve bindirme kuşağının evrimi sırasında minihavzaların çekilmesi ve bölgesel kısalma arasındaki etkileşimi konu edinir. Çoklu ölçekteki bu yapısal analiz Sivas Havzası (Türkiye) ölçeğinde gerçekleştirilmiştir. Kapsamlı saha çalışması ve bölgesel olarak sismik kesitlerden ortaya çıkarılan yorumlamalar, Sivas Havzası’nın orta kesiminde detaylı bir jeolojik haritalama yapımına yardımcı olmuş ve otokton evaporit depolanmasının başladığı Geç Eosen’den başlayarak havza için tuz tektoniği ve bölgesel kısalmanın etkisindeki yeni bir tektono-sedimanter çatının ortaya çıkarılmasına neden olmuştur. Söz konusu seviye, önülke kıvrım ve bindirme kuşağının ilerlemesisüresince kuzeye doğru sedimanter dolgunun göçüyle birlikte havzanın güney kenarında kısalıma uğrayarak ve eğim kazanarak remobilize olmuştur. Evaporit akışı, kıtasal Oligosen minihavzalarının ilksel olarak oluşumundan sonra çekilmesine bağlı olarak gözlenmiş ve sonrasında evaporit yaygılarıyla örtülmüştür. Kuzeye kadar uzanan bu yaygı, Oligosen-Orta Miyosen arasında kıtasaldan sonra sığ denizel tipteki ikincil minihavzaların gelişimine de neden olmuştur.Havzanın orta kesimindeki ikincil minihavza başlangıcı, poligonal diyapir ve duvarlar tarafından çevrelenen dairesel minihavzalarla karakterize olur. Bu minihavzaların kanatlarında halokinetik yapılar tanımlanmıştır. Kanca (hook) ve kama (wedge) tiplerde olmak üzere halokinetik seriler, kompozit halokinetik seriler ve megaflaplar bu yapılar arasında sayılabilir. Çalışmanın başlangıcında yapılan kum kutusu model deneyi, bu halokinetik yapıların kısalmayla veya kısalma olmaksızın geliştiğini göstermiştir. Buna ek olarak minihavzaların geometrisi, muhtemelen tuzun ayrışmasından dolayı tortul yükün ilkkontrolünden dolayı çekilen diğer tuz bölgelerinde önerilen haritalanmış minihavzalara benzerdir. Bununla birlikte kırık ve manyetik suseptibilite analizleri, minihavzaların başlangıcından itibaren kısalmanın kayıt edilebilmesi hakkında fikir vermektedir. Minihavza bölgelerindeki bölgesel kısalımın artışı, tuz duvarları ve diyapirlerin sıkışmasıyla birlikte(i) kısalma yönüne dik durumdaki çizgisel minihavzaların gelişimi, (ii) tuz örtülerinin yerleşimi ve (iii) minihavzaların yer değiştirmesi veya dönmesiyle açıklanır. Minihavzalar bölgesi, kıvrım ve bindirme kuşağının gelişimi için bir süreksizlik üretir. Aslında, minihavzalar birçok yönde yapılar oluşturarak tuz duvarları ve diyapirlerin polygonal şekildeki yerleşimi boyunca kısalma deformasyonuna eşlik eder. Üstelik, tuz yapılarının eşlik ettiği bölgesel kısalma önülke havzalarına doğru evaporitik bir göçe de neden olmaktadır.
244

Characterization of Epoxide Hydrolases from Yeast and Potato

Tronstad-Elfström, Lisa January 2005 (has links)
<p>Epoxides are three-membered cyclic ethers formed in the metabolism of foreign substances and as endogenous metabolites. Epoxide hydrolases (EHs) are enzymes that catalyze the hydrolysis of epoxides to yield the corresponding diols. EHs have been implicated in diverse functions such as detoxification of various toxic epoxides, as well as regulation of signal substance levels.</p><p>The main goal of this thesis was to investigate and characterize the α/β hydrolase fold EH. The first part concerns the identifictaion of an EH in <i>Saccharomyces cerevisiae</i>. The second part involves detailed mechanistic and structural studies of a plant EH from potato, StEH1. </p><p>Despite the important function of EH, no EH has previously been established in <i>S. cerevisiae</i>. By sequence analysis, we have identified a new subclass of EH present in yeast and in a wide range of microorganisms. The <i>S. cerevisiae</i> protein was produced recombinantly and was shown to display low catalytic activity with tested epoxide substrates. </p><p>In plants, EHs are involved in the general defence system, both in the metabolism of the cutin layer and in stress response to pathogens. The catalytic mechanism of recombinantly expressed wild type and mutant potato EH were investigated in detail using the two enantiomers of <i>trans</i>-stilbene oxide (TSO). The proposed catalytic residues of StEH1 were confirmed. StEH1 is slightly enantioselective for the <i>S,S</i>-enantiomer of<i> trans</i>-stilbene oxide. Furthermore, distinct pH dependence of the two enantiomers probably reflects differences in the microscopic rate constants of the substrates. The detailed function of the two catalytic tyrosines was also studied. The behavior of the tyrosine pair resembles that of a bidentate Lewis acid and we conclude that these tyrosines function as Lewis acids rather then proton donors.</p><p>The three dimensional structure of StEH1 was solved, representing the first structure of a plant EH. The structure provided information about the substrate specificity of StEH1.</p>
245

Characterization of Epoxide Hydrolases from Yeast and Potato

Tronstad-Elfström, Lisa January 2005 (has links)
Epoxides are three-membered cyclic ethers formed in the metabolism of foreign substances and as endogenous metabolites. Epoxide hydrolases (EHs) are enzymes that catalyze the hydrolysis of epoxides to yield the corresponding diols. EHs have been implicated in diverse functions such as detoxification of various toxic epoxides, as well as regulation of signal substance levels. The main goal of this thesis was to investigate and characterize the α/β hydrolase fold EH. The first part concerns the identifictaion of an EH in Saccharomyces cerevisiae. The second part involves detailed mechanistic and structural studies of a plant EH from potato, StEH1. Despite the important function of EH, no EH has previously been established in S. cerevisiae. By sequence analysis, we have identified a new subclass of EH present in yeast and in a wide range of microorganisms. The S. cerevisiae protein was produced recombinantly and was shown to display low catalytic activity with tested epoxide substrates. In plants, EHs are involved in the general defence system, both in the metabolism of the cutin layer and in stress response to pathogens. The catalytic mechanism of recombinantly expressed wild type and mutant potato EH were investigated in detail using the two enantiomers of trans-stilbene oxide (TSO). The proposed catalytic residues of StEH1 were confirmed. StEH1 is slightly enantioselective for the S,S-enantiomer of trans-stilbene oxide. Furthermore, distinct pH dependence of the two enantiomers probably reflects differences in the microscopic rate constants of the substrates. The detailed function of the two catalytic tyrosines was also studied. The behavior of the tyrosine pair resembles that of a bidentate Lewis acid and we conclude that these tyrosines function as Lewis acids rather then proton donors. The three dimensional structure of StEH1 was solved, representing the first structure of a plant EH. The structure provided information about the substrate specificity of StEH1.
246

Kvittningsrätten inom fållan : En analys av reglernas förenlighet med den skatterättsliga neutralitetsprincipen / Set-off right within the fold : An analysis of the rules compatibility with the principle of fiscal neutrality

Andersson, Martin, Malm, Andreas January 2015 (has links)
Den 1 juli 2013 meddelade Högsta förvaltningsdomstolen (HFD) beslut i ett mål gällande kvittningsrätten för kapitalvinster och kapitalförluster på delägarrätter. Frågan som be-handlades i målet var om aktiebolaget hade rätt att kvitta sina kapitalförluster mot kapital-vinsterna som uppkommit i den utländska delägarbeskattade juridiska personen. HFD beslutade att neka aktiebolaget möjligheten till kvittning på grund av att lagstöd saknades. Denna bedömning väcker frågor, då aktiebolag som väljer att placera delägarrätter i del-ägarbeskattade juridiska personer får en mindre utsträckt kvittningsrätt vid jämförelse om delägarrätterna hade placerats direkt i aktiebolaget. Vid närmare granskning av kvittnings-möjligheterna kan det konstateras att även kvittningsrätten för kapitalförluster (inte bara kapitalvinster) på delägarrätter i delägarbeskattade juridiska personer är begränsade, vid jämförelse om motsvarande kapitalförluster hade uppkommit direkt i aktiebolaget. Be-gränsningarna för kapitalförlusterna på delägarrätter i delägarbeskattade juridiska perso-ner innebär att kapitalförlusten ska kvoteras till 70 % innan kvittning kan ske, vilket inte är ett krav om kapitalförlusten hade uppkommit direkt i aktiebolaget. Vidare finns varken en sparanderegel eller en koncernkvittningsregel att tillgå i 48 kap. 27 § IL, vilket finns om kapitalförlusten hade uppkommit direkt i aktiebolaget enligt 48 kap. 26 § IL. Frågan som uppkommer är hur dessa begränsningar står i förhållande till den skatterätts-liga neutralitetsprincipen, där den skattskyldiges val ska styras i minsta möjliga utsträck-ning av skattesystemet. Avsteg från denna princip kan göras i syfte att motverka oönskad skatteplanering. Av en samlad bedömning anser skribenterna att samtliga begränsningar av kvittningsrätten för delägarrätter ägda via delägarbeskattade juridiska personer är oför-enliga med neutralitetsprincipen. Detta grundar skribenterna på att aktiebolag som väljer att placera delägarrätter via delägarbeskattade juridiska personer missgynnas ur ett skatte-mässigt perspektiv, vid jämförelse om delägarrätterna hade placerats direkt i aktiebolaget. iii En av de motiveringar som har anförts av lagstiftaren har varit att motverka oönskad skatteplanering. Denna motivering anser skribenterna inte vara hållbar för att rättfärdiga dessa begränsningar. Reglerna borde därmed ändras så att kvittningsmöjligheten på delä-garrätter ägda via delägarbeskattade juridiska personer blir lika omfattande som om delä-garrätterna hade ägts direkt av aktiebolaget. Den framtida existensen av kvittningsrätten på delägarrätter har diskuterats av lagstiftaren och det återstår att se ifall den kommer att avskaffas eller inte. / July 1, 2013, the Supreme Administrative Court (SAC) announced a decision in a case concerning the right to set off of capital gains and losses on securities. The question that was raised in the case was whether the Swedish company had the right to set off their capital losses against capital gains arisen in the foreign part-owner taxable legal person. SAC decided to deny the company the right to set off due to lack of legal support. This decision raises questions, because companies that chooses to place securities in part-owner taxable legal persons gets less extended rights to set off, in comparison to if the securities had been placed directly in the Swedish company. By a closer examination of the possibilities to set off, it can be concluded that the right to set off of capital losses (not just capital gains) on securities in part-owner taxable legal persons are limited, in comparison to if the corresponding capital losses incurred directly in the Swedish com-pany. The limitations of capital losses on securities in part-owner taxable legal persons means that the capital losses should be subject to a quota of 70 % before set off can occur, which is not a requirement when capital losses incurred directly in the Swedish company. Furthermore, there is neither a carry forward rule nor an intra-group set off rule in Chap-ter 48. 27 § Swedish Income Tax Act (SITA), which exists if the capital losses incurred directly in the company according to Chapter 48. 26 § SITA. The question that arises is how these limitations stand in relation to the principle of neutrality where the taxpayer's choices should be controlled as little as possible by the legal tax system. Derogations from this principle can be made in order to coun-teract undesirable tax planning. By an overall assessment the writers consider that all limitations to set off of secu-rities owned via part-owner taxable legal persons are incompatible with the principle v of neutrality. The reason for this opinion is that a company who chooses to place securities via part-owner taxable legal persons is affected adversely from a tax per-spective in comparison to if the securities were owned directly by the Swedish com-pany itself. According to the writers, there is no sustainable justification for these limitations. The rules should therefore be amended so that the set off possibilities on securities owned via part-owner taxable legal persons should be as extensive as if the securities were owned directly by the Swedish company. The future existence of the set-off right on securities has been discussed by the legislature and the future will tell if it will be abolished or not.
247

Modelling Implied Volatility of American-Asian Options : A Simple Multivariate Regression Approach

Radeschnig, David January 2015 (has links)
This report focus upon implied volatility for American styled Asian options, and a least squares approximation method as a way of estimating its magnitude. Asian option prices are calculated/approximated based on Quasi-Monte Carlo simulations and least squares regression, where a known volatility is being used as input. A regression tree then empirically builds a database of regression vectors for the implied volatility based on the simulated output of option prices. The mean squared errors between imputed and estimated volatilities are then compared using a five-folded cross-validation test as well as the non-parametric Kruskal-Wallis hypothesis test of equal distributions. The study results in a proposed semi-parametric model for estimating implied volatilities from options. The user must however be aware of that this model may suffer from bias in estimation, and should thereby be used with caution.
248

Sedimentary, structural, and provenance record of the Cianzo basin, Puna plateau-Eastern Cordillera boundary, NW Argentina

Siks, Benjamin Charles 15 July 2011 (has links)
The fault-bounded Cianzo basin represents a Cenozoic intermontane depocenter between the Puna plateau and Eastern Cordillera of the central Andean fold-thrust belt in northern Argentina. New characterizations of fold-thrust structure, nonmarine sedimentation, and sediment provenance for the shortening-induced Cianzo basin at 23°S help constrain the origin, interconnectedness, and subsequent uplift and exhumation of the basin, which may serve as an analogue for other intermontane hinterland basins in the Andes. Structural mapping of the Cianzo basin reveals SW and NE-plunging synclines within the >6000 m-thick, upsection coarsening Cenozoic clastic succession in the shared footwall of the N-striking, E-directed Cianzo thrust fault and transverse, NE-striking Hornocal fault. Growth stratal relationships within upper Miocene levels of the succession indicate syncontractional sedimentation directly adjacent to the Hornocal fault. Measured stratigraphic sections and clastic sedimentary lithofacies of Cenozoic basin-fill deposits show upsection changes from (1) a distal fluvial system recorded by vi fine-grained, paleosol-rich, heavily bioturbated sandstones and mudstones (Paleocene‒Eocene Santa Bárbara Subgroup, ~400 m), to (2) a braided fluvial system represented by cross-stratified sandstones and interbedded mudstones with 0.3 to 8 m upsection-fining sequences (Upper Eocene–Oligocene Casa Grande Formation, ~1400 m), to (3) a distributary fluvial system in the distal sectors of a distributary fluvial megafan represented by structureless sheetflood sandstones, stratified pebble conglomerates and sandstones, and interbedded overbank mudstones (Miocene Río Grande Formation, ~3300 m), to (4) a proximal alluvial fan system with thick conglomerates interbedded with thin discontinuous sandstone lenses (upper Miocene Pisungo Formation, ~1600 m). New 40Ar/39Ar geochronological results for five interbedded volcanic tuffs indicate distributary fluvial deposition of the uppermost Río Grande Formation from 16.31 ± 0.6 Ma to 9.69 ± 0.05 Ma. Sandstone petrographic results show distinct upsection trends in lithic and feldspar content in the Casa Grande, Río Grande, and Pisungo formations, potentially distinguishing western magmatic arc (Western Cordillera) sediment sources from evolving eastern thrust-belt sources (Puna‒Eastern Cordillera). In addition to growth stratal relationships and 40Ar/39Ar constraints, conglomerate clast compositions reflect distinct lithologic differences, constraining the activation of the Cianzo thrust and coeval movement on the reactivated Hornocal fault. Finally, U-Pb geochronological analyses of sandstone detrital zircon populations in conjunction with paleocurrent data and depositional facies patterns help distinguish localized sources from more distal sources west of the basin, revealing a systematic eastward advance of Eocene to Miocene fold-thrust deformation in the central Andes of northern Argentina. / text
249

Influence of Fenugreek gum on bread and in vitro physiological effects

Roberts, Keisha 18 May 2012 (has links)
ABSTRACT Influence of fenugreek gum on bread and in vitro physiological effects Keisha T. Roberts Advisors: University of Guelph Dr. S.W. Cui Professor T.E. Graham This thesis examined the effect of fenugreek gum, from Canadian grown fenugreek on bread quality, when substituted for wheat flour at 5 % and 10 %, and the in vitro physiological effects of these breads, based on models of acute and long - term feeding. Study I determined bread could be produced with 10 % fenugreek gum, while maintaining quality parameters of volume and texture, comparable to a control. This was accomplished through the development of a novel bread production method, using the lamination procedure for puff pastry production. The behavior of fenugreek gum and starch (wheat flour) was determined by rapid visco analysis (RVA), farinograph and dynamic rheological measurement, while scanning electron microscopy of bread found fenugreek gum could be identified within the bread matrix. Study 2 in vitro starch digestion found fenugreek gum at 5 % and 10 % reduced glucose liberated from bread, with 10 % fenugreek gum causing a reduction of over 30 %. RVA of fenugreek breads highlighted differences in viscosity between breads and wheat flour substituted with the gum. This was substantial as viscosity measurements by RVA are conducted on raw ingredients and not the food as consumed, which reflects the possible reduction in viscosity with food processing. This study also determined extruding fenugreek gum may have caused morphological changes to the gum, which may possibly contribute to attenuation of glucose liberated in vitro. Study 3 evaluated the accumulation of short chain fatty acids (SCFA) from the fermentation of three substrates: Extruded fenugreek gum, bread with 10 % extruded gum and control bread, based on fecal microbiota from three donors. SCFA profiles varied with substrates and donors, with fenugreek gum having the highest accumulation of SCFA after 12 hours. Donors were a caucuasian Canadian, a black Jamaican and a black Trinidadian who was the only donor culturally exposed to fenugreek. This Trinidadian’s SCFA profiles were consistently higher for fenugreek gum than the other donors. These studies collectively showed fenugreek gum, though viscous could be successfully incorporated into bread and have potential as a functional food and nutraceutical.
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Petrologia e geocronologia do Maciço Glória Norte, faixa de dobramentos sergipana, NE do Brasil

Lisboa, Vinícius Anselmo Carvalho 11 March 2014 (has links)
O Domínio Macururé, localizado na porção norte da Faixa de Dobramentos Sergipana, é caracterizado por apresentar um grande volume de granitos (s.l.) de idade Neoproterozóica. O Maciço Glória Norte (MGN), que ocorre na porção centronorte do Domínio Macururé, representa uma das mais importantes intrusões que se colocaram após o pico de deformação e metamorfismo no orógeno (630 Ma). Nesse estudo identificou-se a presença de duas fácies petrográficas nesse maciço: quartzomonzonítica porfirítica, quartzo-monzonítica, além de diques leucocráticos. Os enclaves de diversos tipos, são uma feição recorrente em toda a extensão do maciço, assim como texturas evidenciam a existência do processo de misturas entre magmas. Os estudos microscópicos permitiram a identificação de várias texturas de instabilidade, e uma sequência de cristalização marcada pelo aumento de fluídos ao longo da evolução do magma. Os dados geoquímicos revelam uma afinidade com as rochas da série shoshonítica e seus enclaves exibem afinidade ultrapotássica com conteúdos de MgO e K2O sempre maiores que 3%. Nos diagramas ETR percebeuse um enriquecimento de ETR leves em relação aos pesados, além de fortes anomalias negativas de Ta, Nb, Ti, P, Sr e Eu, principalmente nos enclaves. As temperaturas médias calculadas pelo geotermômetro de Zr revelam que o início da cristalização no MGN se deu entre 810°C e 784°C e teve seu fim entre 730°C e 700°C. A idade obtida através do método U/Pb SHRIMP (588 + 5,2 Ma) posiciona o magmatismo que deu origem ao MGN, no Período Ediacarano, marcando a ocorrência de um magmatismo a 588 Ma, que não foi afetado por eventos tectônicos. / The Domain Macururé located in the northern portion of Sergipano Fold Thrust Belt, is characterized by having a large volume of granites (s.l.) of Neoproterozoic age. The Gloria Norte Massif (GNM), which occurs in the north-central portion of the Domain Macururé, represents a major intrusion that arose after the peak of deformation and metamorphism in the orogen (+ 630 Ma). In this study we identified the presence of two petrographic facies in that massif: quartz-monzonitic porphyritic, quartz-monzonitic and leucocratic dykes. The enclaves, varied tipology, are a recurrent feature in the whole extent of the massif, as well as mixtures of texture of mixing and mingling. Microscopic studies allowed the identification of various textures of the mixing and a sequence of crystallization marked by increased fluids during the evolution of the magma. Geochemical data reveal an affinity with shoshonitic series rocks, and their enclaves exhibit ultrapotassic affinity, wich always show MgO and K2O contents greater than 3%. In the diagrams ETR perceives an enrichment of LREE relative to HREE, and strong negative anomalies of Ta, Nb, Ti, P, Sr, and Eu, mostly in enclaves. The average temperature calculated by Zr geothermometer showed that the onset of MGN crystallization occurred between 810°C and 784°C, and its end was between 730°C and 700°C. The ages obtained by U/Pb SHRIMP (588 + 5.2 Ma) positions the magmatism that gave rise to the MGN, in the Ediacaran and this age mark the occurrence of a magmatism (588 Ma), which was not significantly affected by tectonic events.

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