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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.
111

Fytotoxicita průsakových vod ze skládky odpadů Štěpánovice

Heralová, Kateřina January 2017 (has links)
Thesis on Phytotocity leachate from landfills Štěpánovice deals with basic concepts and legislation related to municipal waste and landfill in theoretical part. There are also procedures in waste management, their hierarchy, and statistical evaluation of the amount of multicipan waste. Another part of a literature search is aimed at monitoring water, general description of the storage process and general description of phytotoxicity. The practical part describes the process of solid municipal waste landfill Štěpánovice, its natural circumstances, locations and the integration in the territory. There is also described and discussed experiment which was realized by semi-chronic toxicity leachate method with white mustard (Sinapis alba L.). Followed by evaluation of the results and their interpretation in the current comparison of results with other writers.
112

Bříza bělokorá jako přípravná dřevina při zalesňování kalamitních holin jedlí bělokorou: vliv na podmínky prostředí a vybrané ekofyziologické parametry jedle

Štefková, Veronika January 2017 (has links)
This thesis compare various uses of silver birch (Betula pendula Roth.) as a preparatory species during afforestation by silver fir (Abies alba Mill.). In this experiment, silver fir was planted at fall of 2015 and measurements were conducted in the vegetation season 2016. There were four variants of experiment with respect to the silver birch: clearcut, birch stand with 50 % stocking density, narrow embankment cut and birch stand with a full stocking density. Air temperature, precipitation, vapor pressure deficit, soil moisture and transmittance of photosynthetically active radiation were measured from the environmental variables. On plants, the growth increment, chlorophyll fluorescence, shoot water potential and needle mas per area were studied. Preparatory forest stand eliminated extreme temperatures, both positive and negative. Maximum temperatures were by 7 °C lower under the forest canopy than on clearcut. Spring frost was eliminated by 2.2 °C which was enough to protect fresh shoots from freezing. On the other hand soil moisture under the birch was by 23 till 47 % lower than at the clearcut. Tallest growth increment of 12 cm was at the clearcut, shortest of 7 cm under the birch without thinning. Needle mass per area corresponded to light availability and it was highest at clearcut and lowest under the birch. Chlorophyll fluorescence in dark did not suggest any differences between treatments (Fv/Fm was higher than 0.80) and therefore differences in growth can be accounted to the light availability. Data suggest that for the silver fir saplings is best to grow under severely thinned silver birch canopy with low stocking density which allows for enough light and soil moisture but still protects saplings against inclement weatherFormula clause:I declare that I am working, "Birch as a preparatory tree species in reforestation calamity clearings silver fir: the impact of environmental conditions and selected ecophysiological parameters fir" worked independently and all used sources and information mention in the list of references. I agree that my work has been published in accordance with § 47 b of the Act no. 111/1998 Coll., On universities, as amended and in accordance with directives on the publication of university theses. I am aware that my work covered by Act no. 121/2000 Coll., The Copyright Act, and the Mendel University in Brno has the right to conclude a license agreement and use this work as school work pursuant to Section 60 paragraph. 1 of the Copyright Act. I also agree that, before drawing up licensing agreements on the use of a work by another person (the subject), I request a written opinion by the university that the subject license agreement is not contrary to the legitimate interests of the university and undertake to pay any contribution to the costs associated with the creation of the work, and up to the full amount
113

Das Phänomen der Alba Brangänes aus Tristan und Isolde von Richard Wagner

Wolanski, Andrzej 25 August 2017 (has links)
Richard Wagner war von der mittelalterlichen Welt des Minnesangs fasziniert. In der Szene des zweiten Aktes des durch das Poem von Gottfried von Straßburg inspirierten Dramas Tristan und Isolde befindet sich ein wunderschönes Lied, die Alba, das von Brangäne gesungen wird, als sie über die 'in der Liebesumarmung' Tristans 'verharrende' Isolde wachte.
114

Potential of Great Egrets to be Vectors for the Transmission of s Virulent Strain of Aeromonas Hydrophila between Channel Catfish Culture Pond

Jubirt, Madison McCall 11 August 2012 (has links)
Aeromonas hydrophila is a Gram-negative, rod shaped, facultative anaerobic bacterium that is ubiquitous to freshwater and slightly brackish aquatic environments and can cause infections in fish, humans, reptiles, and avian species. Recent severe outbreaks of disease in catfish aquaculture have been associated with a highly virulent Aeromonas hydrophila strain (VAH) that is genetically distinct from less virulent strains. Given that A. hydrophila is known to infect birds, we hypothesized that fish eating birds may serve as a reservoir for VAH and spread the pathogen by flying to uninfected ponds. Great Egrets were used in this transmission model because these wading birds frequently predate catfish farms. We found that Great Egrets that were fed VAH infected catfish shed VAH demonstrating their potential to spread VAH. Histologically there were changes found in selected tissue samples.
115

A Design Concept for the Lighting Design of Federico Garcia Lorca's The House of Bernarda Alba

Kramer, Thaddeus L 01 January 2011 (has links) (PDF)
A discussion of the abstract approach for the lighting design of the Theater Department’s Fall 2010 production of Federico García Lorca’s The House of Bernarda Alba through the use of time of day and “clean and dirty” light.
116

Mechanistic Studies and Inhibition of N-hydroxylating Monooxygenases

Bufkin, Kendra Bernice 23 May 2017 (has links)
N-hydroxylating monooxygenases (NMO) are members the class B flavoprotein monooxygenases. They catalyze the N-hydroxylation of lysine and ornithine and play and essential role in the biosynthesis of hydroxamate containing siderophores. Siderophores are high affinity iron-chelators composed of catechol and hydroxamate functional groups that are synthesized and secreted by several microorganisms and plants. It has been showed that many NMOs are essential for virulence in many opportunistic pathogens such as Aspergillus fumigatus and Pseudomonas aeruginosa. The focus of my research is on the N-hydroxylating enzymes: Siderophore A (SidA) from Aspergillus fumigatus and Amycolatoposis alba monooxygenase (AMO). One of my projects is focusing on identifying inhibitors of SidA that will ultimately block the siderophore biosynthesis in A. fumigatus. Out of 973 compounds screened using an activity high-throughput assays two compounds were identified. These were, wortmannin a steroid metabolite and ebselen a benzoselenazole as SidA inhibitors with IC50 values of 369 µM and 11 µM respectively. A second part of this works investigates the hydroxamate formation of the siderophore albachelin in Amycolatoposis alba with the purpose of better understanding this class of enzymes and their catalytic mechanism. The enzyme was purified and characterized in its holo (FAD-bound) and apo (unbound) forms. Pre-steady and steady state kinetics shows that the two forms have different coenzyme preference; apo-AMO prefers NADH while holo-AMO has a higher affinity to NADPH. / Master of Science in Life Sciences
117

Interactions plantes-insectes dans deux écosystèmes forestiers méditerranéens contrastés : le cas des scolytes (Coleoptera Curculionidae Scolytinae) en région méditerranéenne / Plant-insect interactions in two contrasting forest ecosystems : bark beetles (Coleoptera Curculionidae) in Mediterranean area

Durand-Gillmann, Marion 07 February 2014 (has links)
Les écosystèmes forestiers méditerranéens présentent des espèces d'arbres vivant en limite sud de leur aire de répartition sensibles aux stress climatiques et des espèces vivant au coeur de leur aire de répartition et a priori adaptées à ces mêmes stress. Ces contrastes interrogent sur la diversité potentielle des mécanismes régulant la dynamique des populations de leurs parasites, et en retour l'impact des parasites sur la dynamique de leurs hôtes. Les scolytes constituent un bon modèle pour l'étude de ces interactions hôte-parasite car ils alternent des phases endémiques et épidémiques. Nous avons développé une approche pluridisciplinaire couplant la caractérisation de traits écophysiologiques et dendrométriques impliqués dans la résistance des populations d'arbres aux attaques de scolytes avec la caractérisation de facteurs écologiques clés pour la démographie des scolytes. Chez le pin d'Alep, T. destruens est présent à un niveau endémique mais des attaques subsistent dans des patchs d'arbres formés par des arbres attaqués et morts suite aux attaques, des arbres attaqués qui ont résisté et des arbres non attaqués. Des stratégies de dispersion locale différentes selon les deux grandes phases du cycle de T . destruens semblent favoriser l'exploitation d'une ressource peu abondante. Chez le sapin pectiné, nous avons montré qu'une communauté abondante de scolytes s'attaque à des arbres déjà affaiblis par des sécheresses répétées et présentant un mauvais état sanitaire et une croissance en baisse. Ces deux écosystèmes forestiers permettent de mieux appréhender les mécanismes impliqués dans les interactions plantes-insectes dans un contexte de changement global. / Mediterranean forest ecosystems have both trees living in their southern range and being sensitive to climatic stress and tree species living in the core of their range and being non sensitive to the same stress. These contrasts in tree populations questioned about potential contrasts in their interrelationships with their parasites and on the impact of that parasites have on their host in turn. Bark beetles are a relevant model to study such host-parasite interactions because they alternate endemic and epidemic phases. We developed a multidisciplinary approach combining the characterization of ecophysiological and dendrometrical traits involved in resistance of tree populations to bark beetle attacks with this assessment of key ecological factors involved in bark beetles demography. We focused on the two following contrasted Mediterranean ecosystems in South-Eastern France: a healthy Aleppo pine interacting with a bark beetle population at an endemic state and a declining population of the Silver fir interacting with a bark beetle community at an epidemic state. Our results suggested that this Aleppo pine population, the pine shoot beetle T. destruens showed low abundance levels. All attacks remained in patches formed by dead trees following the attacks. T. destruens dispersal strategies seem to favor the exploitation of a scarce resource. On silver fir, we showed a bark beetle community attacking trees already weakened by repeated droughts and with poor health status and low growth. The study of these two contrasted forest ecosystems allowed us to shed some critical light on the mechanisms involved in plant-insect interactions in the context of global change.
118

Les contributions de la pratique de l'arbitrage d'investissement en Amérique latine au développement de l'arbitrage international / From the contributions to Arbitration practices in Investment in Latin America to development to International Arbitration

Vasquez-Faucheux, Hilmer 30 November 2015 (has links)
Depuis les années deux-mille, les Etats latino-américains ont activement participé aux arbitrages d’investissement administrés par le Centre international pour le règlement des différends relatifs aux investissements (CIRDI). Ainsi, la pratique arbitrale de ce Centre trouve son origine dans les très nombreuses affaires latino-américaines qui ont permis d’encadrer la procédure et d’entériner certaines pratiques liées aux questions de fond de l’arbitrage. Les affaires latino-américaines ont enrichi la procédure en consacrant notamment la participation des tiers à la procédure arbitrale par le biais de l’amicus curiae (l’ami de la Cour). Cette innovation démontre la prise en compte de l’impact des questions d’intérêt public sur les populations concernées. Les divers standards juridiques insérés dans les accords d’investissement ont également été invoqués par les investisseurs afin de voir engagée la responsabilité internationale des Etats. Ainsi, les arbitres ont pu s’exprimer sur le caractère imprécis de certains standards comme celui du traitement juste et équitable. Les tribunaux ont dégagé certains étalons de mesure qui permettent d’évaluer et de comparer les éléments de l’affaire. Deux étalons de mesure semblent être pertinents dans le cas latino-américain. Il s’agit du respect de la stabilité du cadre juridique puis de la protection des attentes légitimes de l’investisseur. C’est dans ce cadre que les Etats latino-américains ont réagi différemment face au contentieux arbitral auprès du CIRDI, ce dernier ayant fait l’objet de critiques quant à sa légitimité et quant aux différentes condamnations prononcées par les tribunaux à l’encontre des Etats. Certains Etats ont pris l’initiative de dénoncer les accords internationaux donnant compétence au CIRDI et de créer un nouveau centre d’arbitrage sur le continent, capable de connaître les différends en matière d’investissement. Ceci dit, les décisions et sentences arbitrales rendues dans le contexte latino-américain constituent une source d’inspiration précieuse pour les arbitrages internationaux en cours et futurs. / Since 2001, Latin American Countries have actively participated in investment arbitrations administered by the International Centre for Settlement of Investment Disputes (ICSID). Because of that the way to arbitrate in this Centre base itself on a great number of Latin American affairs which helped to delimit the procedures and endorse some practices linked to the very founding principles of arbitration.The procedure of arbitration has been improved by Latin American affairs, by example with the help of the Amicus Curiae, which is the participation of a third party to the arbitral process. This innovation shows how much these questions of public interest are important for the populations concerned.The multiple juridical standards inserted in the investment agreements have often been brought forward by the investors in order to see the responsibility of some countries engaged in an international way. Arbitrators have been able to emphasize on the inaccuracy of some of these standards, such as the the fair and equitable treatment.Different ways to measure the elements of an affair have been brought to light by the tribunals. Two of them are present in the case of Latin American affairs: the compliance with the juridical framework stability and the protection of the investor's legitimate expectations.Latin American countries did take action differently in front of the arbitrations brought to the ICSID which was criticized for its lack of legitimacy and for its decisions in a great number of cases against these countries. Some countries renounced the international treaties giving the ICSID its arbitration rights and created a new arbitration center on the continent capable of giving a ruling in the matter of investment affairs. In spite of this the arbitral decisions and the arbitral awards in the Latin American context should be able to be inspirations for the future of arbitration.
119

Ekstrakti duda (Morus spp., Morasceae), sastav, delovanje i primena / Mulberry extracts (Morus spp., Morasceae), composition, activity and application

Radojković Marija 09 November 2012 (has links)
<p>&nbsp;Upotrebom različitih ekstragenasa izvr&scaron;ena je ekstrakcija ploda, lista i korena belog (<em>Morus alba</em> L.) i crnog duda (<em>Morus nigra</em> L. ). Ekstrakcija etanolom je izvr&scaron;ena pri predhodno određenim optimalnim uslovima ekstrakcije (70% koncentracija etanola, temperatura 60&deg;C i odnos rastvarač:droga 20 ml/g). Ispitan je hemijski sastav ekstrakata različitih delova duda. Ispitivanja hemijskog sastava etanolnih ekstrakata obuhvatala su određivanje sadržaja ukupnih fenola, ukupnih flavonoida, ukupnih i monomernih antocijana, kvalitativni i kvantitativni sastav polifenolnih komponenata, kao i sadržaj mikro-, makro- i toksičnih elemenata. Najvedi sadržaj ukupnih fenolnih jedinjenja određen je u ekstraktu korena <em>M. nigra</em> (186 mg EHK/g), a najvedi sadržaj flavonoidnih jedinjenja u ekstraktu lista <em>M. nigra</em> (67 mg ER/g). U ekstraktima lista duda po svom sadržaju u odnosu na ukupan sadržaj polifenolnih jedinjenja ističe se kafena kiselina (od 53,34 do 62,11%), dok se u ekstraktima korena izdvaja hlorogenska kiselina (udeo vedi od 74%). U pogledu mineralnog sastava ekstrakata relativno veliki sadržaj Ca i Mg je karakterističan za obe vrste ekstrakata (vedi od 1.400 &mu;g/g). Mikroelementi u svim ispitanim uzorcima duda po opadajudem nivou, su Fe, B, Zn, Cu i Mn. U ekstraktima dobijenim superkritičnim CO<sub>2 </sub>određen je sadržaj masnih kiselina i ukupnih karotenoida. U ispitivanim ekstraktima dominante su nezasidene masne kiseline, linolna i linolenska kiselina, a značajan je udeo i zasidene masne kiseline (palmitinske kiseline).</p><p>Ispitivanje delovanja ekstrakata obuhvatalo je evaluaciju antioksidativne aktivnosti pradenjem sposobnosti neutralizacije slobodnih radikala, redukcionog potencijala i inhibicije lipidne peroksidacije. Po svim primenjenim metodama najvedu aktivnost je pokazao ekstrakt lista crnog duda. U zavr&scaron;noj fazi rada ispitana je in vitro citotoksična aktivnost ekstrakata duda, njihovim delovanjem na rast tri delijske linije: Hep2, RD i L2OB. Ekstrakti lista <em>M. nigra</em> su se pokazali kao najpotentniji inhibitori&nbsp;rasta na sve tri delijske linije (IC<sub>50</sub>&lt;30 &mu;g/g). Na osnovu svih sprovedenih ispitivanja kao proizvod sa najboljim karakteristikama pokazao se ekstrakti lista <em>M. nigra</em>.</p> / <p>Using different extraction solvents extracts of fruit, leaves and roots of white (<em>Morus alba</em> L.) and black mulberry (<em>Morus nigra</em> L.) were prepared. Extraction by ethanol was carried out at the previously determined optimal extraction conditions (70% ethanol concentration, temperature 60&deg;C and the ratio of solvent: drug 20 ml/g). The chemical composition of extracts obtained from different parts of the mulberry were analysed. These analyses included the determination of total phenols, total flavonoids, monomeric and total anthocyanins, qualitative and quantitative composition of polyphenolic components, and the content of micro-, macro- and toxic elements. The highest phenolic content was determined in the extract of <em>M. nigra</em> root (186 mg ECA/ g), while the highest content of flavonoid compounds was determined in the extract of <em>M. nigra</em> leaves (67 mg ER/g). In the case of mulberry leaf extracts dominant phenolic compound, in relation to the total phenolic content, was caffeic acid (with contribution from 53.34 to 62.11%), while in the extracts of root extracts dominant phenolic compounds was chlorogenic acid (a higher proportion of 74%). In terms of mineral composition of the extracts relatively high content of Ca and Mg was characteristic of both types of extracts (greater than 1,400 mg/g). Measured content of trace elements in mulberry extracts decrease in the next order: Fe&gt; B&gt; Zn&gt; Cu&gt; Mn. In the extracts obtained by supercritical CO<sub>2</sub> fatty acids and total carotenoids were determined. In these extracts dominant unsaturated fatty acids were linoleic and linolenic acid. Also, significant proportion of saturated fatty acid (palmitic acid) has been detected.</p><p>Testing of extracts activity included the evaluation of antioxidant activity applying the methods based on: neutralize free radicals, reducing power potential and the inhibition of lipid peroxidation. All applied methods showed the highest activity of black mulberry leaf extract. In the final phase of work in vitro cytotoxic activity of mulberry extracts was examined. Their effect on growth of three cell lines: Hep2, RD, and L2OB were analysed. Extracts of <em>M. nigra</em> proved to be the most potent inhibitors of growth in all three cell lines (IC<sub>50</sub>&lt;30 mg/g). On the basis of all conducted tests it has been proven that <em>M. nigra</em> extracts are products with the best characteristics.</p>
120

Contribution des méthodes chiroptiques à l'analyse et à la caractérisation des huiles essentielles / Chiroptical contribution methods for the analysis and characterization of essential oils

Said, Mohammed El Amin 22 February 2016 (has links)
Les huiles essentielles sont connues pour leur richesse en molécules chirales. L'identification et la caractérisation de ces différentes molécules en termes de la configuration absolue des énantiomères majoritaires représente un important pas dans la compréhension des actions thérapeutiques des huiles essentielles. Dans le cadre de cette thèse, une étude est réalisée sur la composition chimique des huiles essentielles de quelques plantes aromatiques du Sahara algérien (l'Artemisia herba-alba, le Bubonium graveolens et l'Artemisia arborescens) ayant un usage fréquent dans la pharmacopée traditionnelle. Différentes techniques analytiques chromatographiques telles que la CG-SM classique et chirale, la CLHP chirale et spectroscopiques comme l'IR et le VCD seront mises en œuvre afin d’étudier les constituants chiraux de ces HE pour la connaissance de leurs signatures chiroptiques qui peuvent être des paramètres essentiels pour leurs caractérisations. En associant la performance du traitement chimiométrique, la fiabilité des techniques spectroscopiques et le potentiel discriminant de la signature chirale, nous avons développé des outils de caractérisation, de contrôle qualité et de traçabilité des HE. Les configurations absolues de la (-)-α-thujone, la (+)-β-thujone, l'acetate de (-)-cis-chrysanthenyl, le (+)-oxocyclonerolidol et l'acetate de (-)-cis-acetoxychrysanthenyl ont été obtenues par la comparaison des spectres VCD expérimentaux et calculés et on a montré qu'on peut utiliser le VCD pour l'étude et la modélisation des matrices complexes. / Essential oils are known for their richness in Chiral molecules. Identification and characterization of these different molecules in terms of absolute configuration of the majors enantiomers represents an important step in the understanding of the therapeutic actions of essential oils. In this thesis, a study was done to investigate the chemical composition of the essential oils of some aromatic plants of the Algerian Sahara (Artemisia herba-alba, Bubonium graveolens and Artemisia arborescens) frequently used in the traditional pharmacopoeia. Different chromatographic analytical techniques such as classic and chiral GC-MS, chiral HPLC and spectroscopic techniques as IR and VCD will be implemented to study the chiral constituents in these EO for the knowledge of their chiroptical signatures which can be essential parameters for their characterizations. Combining chemometrics processing performance, reliability of spectroscopic techniques and potential discriminating chiral signature, we have developed tools for the characterization, quality control and traceability of EO. Absolute configuration of (-)-α-thujone, (+)-β-thujone, (-)-cis-chrysanthenyl acetate, (+)-oxocyclonerolidol and (-)-cis-acetoxychrysanthenyl acetate were obtained by comparison of calculated and experimental VCD spectra and we demonstrated that VCD can be used for the study and modeling of complex matrices.

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