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This diploma thesis concerns in design and realization of assembling line of a 2/2 seat valve for commercial vehicles sector. Design is using Autodesk Inventor. Thesis describes phases and goals of project management – in this case management of technological/manufacturing transfer.

La synthèse de β-aminoacides, analogues structurels des -aminoacides, constitue un enjeu essentiel dans le développement d'oligopeptides. Un long travail a été mené sur le comportement des β-peptides (enchaînement de β-aminoacides) ainsi que les peptides mixtes (mélange d'β- et β- aminoacides). Il en résulte que la préférence conformationnelle des β-aminoacides va induire l'apparition d'une structure tridimensionnelle ordonnée de l'oligopeptide. Ainsi, plusieurs types d'hélices, des feuillets et des coudes ont été observés sur des β-oligopeptides. En plus de cette fascinante particularité, les β-peptides et les peptides mixtes ont montré une grande stabilité vis-à-vis des enzymes digestives. Ces caractéristiques sont importantes dans le développement de nouveaux médicaments, mimes de structures protéiques. Au laboratoire, nous travaillons sur le β-aminoacide cyclobutanique comme bloc de construction de structures moléculaires élaborées dont les β-peptides. La partie bibliographique, scindée en deux parties, décrit la synthèse deβ-aminoacides carbocycliques puis les différents types de structures secondaires obtenus à partir de peptides composés de β-aminoacides. Des travaux ont été menés sur les β-aminoacides cycliques à 6, 5 et à 4 chaînons. Cependant, aucuns travaux n'ont été décris sur le trans-β-aminoacide cyclobutanique " trans-ACBC ". Nous avons entrepris d'accéder au cis- et trans-ACBC optiquement enrichis et nous avons mis au point deux voies de synthèse à l'échelle multigramme. L'étape clé, commune aux deux synthèses et la photocycloaddition [2+2] entre l'éthylène et un partenaire ènone pour créer le cyclobutane. A l'aide de méthodes de couplages peptidiques, nous avons préparé le dimère, le tétramère, l'hexamère et l'octamère du 1R,2R- trans-ACBC. Grâce à plusieurs techniques de caractérisation couramment utilisées dans l'étude conformationnelle de polypeptides, nous avons pu déterminer avec certitude l'existence d'une hélice- 12 dès l'hexamère. En parallèle, nous avons mené une étude complète de modélisation moléculaire qui nous a conduits à un résultat identique. Ce travail sur la synthèse des ACBC optiquement pures et sur le comportement des β-peptides cyclobutaniques complète le tableau des β-peptides carbocycliques. Nous envisageons de préparer des β-aminoacides cyclobutaniques fonctionnalisés, afin de construire des β-peptides structurés, destinés à une application en chimie médicinale.

Florida's undergraduate organization of higher education is a 2 + 2 system in which students are encouraged to complete freshmen and sophomore years at a community college and then transfer to a state university. Florida statutes provide for a highly articulated educational system to facilitate seamless transition from one public institution to another. The researcher investigated the transfer function's effectiveness among community college students subsequent to enrollment at a large, urban, doctoral/research extensive university in Florida using a course-based model of transfer success. The research explored whether differences existed in academic performance in targeted upper-division undergraduate courses between native and Florida Community College System (FCCS) transfer students who completed prerequisite courses prior to transferring to the university. Four upper-division courses were chosen specifically because many transfer students complete prerequisite coursework at a community college prior to matriculating at the university. A total of 764 native students and 1,053 FCCS transfer students were enrolled in at least one course of interest in fall 2002. Preliminary investigation of selected demographic characteristics identified statistically significant differences between these two groups. Native students were younger and more racially/ethnically diverse; more native students were enrolled full time (for 12 or more credits) than transfer students. Although first-term transfer students experienced transfer shock, university native students who were enrolled in three courses also experienced declines in fall 2002 GPA when compared to their previous GPA at the university. Statistically significant mean grade differences occurred between transfer and native students in three courses; transfers outperformed native students in two courses. Additional comparisons of fall 2002 term GPA between native and transfer students yielded no significant differences. Findings lend support to the effectiveness of Florida's community colleges in preparing students for upper-division undergraduate coursework, but that transition for some is not seamless, suggesting need for collaboration among universities and community colleges.

Ce mémoire est articulé autour de trois chapitres. En premier lieu, nos nouveaux résultats concernant la synthèse de 3-silapiperidines par voie dianionique sont présentés. Le chapitre suivant traite de nos premières études sur les mécanismes mis en jeu, au cours de la cycloisomérisation d'enynes-1,5 catalysée par PtCl2, lors de la formation de systèmes [3.1.0]-bicycliques. Enfin, le dernier chapitre concerne nos travaux en collaboration avec l'université préfectorale d'Osaka, sur la formation de résorcinols fonctionnalisés, à partir de pivalate vinylpropargyliques par carbonylation catalytique au [RhCl(CO)2]2.

The modern world faces a number of challenges related to energy and the environment. Atmospheric levels of carbon dioxide have now surpassed the 400 ppm mark due to the burning of fossil fuels, yet despite its abundance and potential use as a C1 feedstock for value-added products, there are both thermodynamic and kinetic barriers associated with the strong carbon-oxygen bonds that preclude its widespread deployment in industry. Nuclear energy is an alternative power source that reduces carbon emissions by billions of tonnes each year, but there are widespread concerns regarding the treatment of the radioactive waste that it accrues (of which the main component is uranyl, [UO2]2+). Most of the work presented in this thesis concerns the synthesis of transition-metal complexes, with the aim of directing catalytic reactivity to convert CO2 to useful products. Part of this thesis also concerns the synthesis of uranyl complexes and the study of uranyl reduction chemistry, which is relevant to uranyl remediation and nuclear waste treatment at a fundamental level. Making use of Earth-abundant metals to carry out hydrocarbon oxidation catalysis is a further focus of this work, as the efficient production of oxygenated compounds under mild conditions is of importance to the fine-chemical industry. Chapter 1 reviews important complexes reported in the literature that successfully convert CO2 to useful products through molecular, homogenous electro-catalysis and ring-opening copolymerisation catalysis. Reactions that exemplify a two-electron reduction of uranyl (i.e. uranium(VI) to uranium(IV)) are reviewed, along with uranyl complexes that undergo ligand-centred redox to give ligand-based radicals. The state of the literature on hydrocarbon oxidation catalysis is reviewed in the introduction. The development of multinuclear, macrocyclic complexes and the reactivity of dinuclear Pacman complexes are also presented. Chapter 2 reports the synthesis and characterisation of a new set of Schiff-base macrocycles and acyclic dipyrrin ligands. A number of attempted synthetic routes towards incorporating a dipyrrin coordination compartment in a macro-cyclic setting are discussed. Differences in electronic structures between dipyrromethanes and dipyrromethenes are also examined by theoretical and experimental methods. Chapter 3 introduces the coordination chemistry of these new macrocycles with zinc(II), where the isolation of dinuclear and tetranuclear complexes is demonstrated using different zinc(II) precursors. Tetranuclear zinc-alkyl complexes presented here are shown to be resistant to insertion chemistry with small molecules, but readily form zinc-oxo, -hydroxyl and -alkoxide clusters upon protonolysis with water and alcohols. These molecular clusters display reactivity towards CO2: a zinc-hydroxyl complex precipitates ZnCO3 at high temperature; and zinc-alkoxide complexes have been used to catalyse the copolymerisation reaction between CO2 and cyclohexene oxide to form polycarbonates. Chapter 4 describes the synthesis of late-transition-metal complexes of macrocyclic ligands and dipyrrins, and explores the relationship between macrocycle geometry and electronic structure. Their reactivities towards CO2 are assessed here, using cyclic voltammetry to assess the electro-catalytic activity of a number of the complexes. Chapter 5 reports the oxidation chemistry of hydrocarbon substrates catalysed by copper(II) complexes. High-temperature catalysis occurs with bimetallic copper(II) complexes, and this chapter describes how added FeCl3 acts as a co-catalyst, leading to greater catalyst stability and allowing the catalytic reaction to occur at room temperature. A range of analytical methods have been used to deduce the catalytically active species, and chemical kinetic measurements have been used to deduce a possible reaction mechanism. Chapter 6 reports the synthesis of a uranyl(VI) dipyrrin complex and details characterisation of its electronic structure by theoretical and experimental methods. Theoretical modelling has indicated that the observed two-electron reduction of uranium(VI) to uranium(IV) is facilitated by the dipyrrin ligand, representing a novel uranyl reduction mechanism.

In recent decades, insect sex pheromones are playing an increasingly important role in the detection, monitoring and control of pests, becoming part of Integrated Management strategies and helping to reduce the amount and use of conventional pesticides. The implementation of control techniques based on pheromones makes it necessary to obtain these substances through organic synthesis. Oleander Scale, Aspidiotus nerii Bouché, 1833, is a cosmopolitan and polyphagous pest that attacks more than 100 plant families. In Spain, it is a coccoid pest of medium-importance for citrus crops, after California red scale (Aonidiella aurantii Maskell), Chaff scale (Parlatoria pergandii Comstock) and Purple scale (Lepidosaphes beckii Newman). Conventional chemical control against Oleander scale is sometimes ineffective due to the biology of the pest and the increasing restrictions on the number of available pesticides; thus, a possible treatment of this pest based on its sex pheromone would be highly valuable. The sex pheromone of A. nerii was identified by Einhorn et al. in 1998 as (1R,2S)-cis-2-isopropenyl-1-(4¿-methyl-4¿-penten-1¿-yl)cyclobutaneethanol acetate. Its synthesis has been approached by various authors but the synthetic routes described until now have a high number of synthetic stages and a low overall yield, which makes it not suitable for a multigram scale synthesis. It can be highlighted the synthesis of Einhorn et al., in 1998, involving 17 steps and an overall yield of 0.40% or the total synthesis developed in the same year by Guerrero et al., with 15 steps and an overall yield of 5.6%. For these reasons, this thesis addresses the development of a synthetic route that improves the existing ones to obtain the sex pheromone of A. nerii at a multigram scale. The synthetic route developed in this work is based on low cost commercial substrates such as 3-hydroxypropanenitrile, which can be transformed into the pheromone of interest using only 10 steps and with an overall yield of 10.3%. The proposed route employs simple purification procedures and several reactions including a Blaise reaction and a [2 + 2] photocycloaddition as key reactions. In addition, some of the synthetic intermediates obtained in this proposed route have high interest to improve the synthesis of the aggregation pheromones of Diaprepes abbreviatus Linnaeus and Trypodendron lineatum Olivier, which represent important pests in different countries. The possibility of obtaining a sufficient amount of A. nerii sex pheromone has allowed the realization of field trials, which are expected to contribute significantly to the development of alternative techniques for the control of this pest in crops of interest in Spain and other countries. / El uso de las feromonas sexuales de insectos para la detección, seguimiento y control de plagas ha ido creciendo de manera constante en los últimos años, convirtiendo a estas sustancias en una de las herramientas más importantes en la lucha contra poblaciones de insectos dentro del Manejo Integrado de Plagas, ayudando así a reducir la cantidad y el uso de plaguicidas convencionales. La aplicación de estas técnicas hace necesaria la obtención de estas sustancias mediante síntesis orgánica. El piojo blanco del limón Aspidiotus nerii Bouché, 1833, también conocido como piojo de la adelfa (Oleander scale), es una plaga cosmopolita y polífaga que ataca a más de 100 familias de plantas. En España constituye una plaga de cóccidos de importancia media en el cultivo de cítricos después del piojo rojo de California (Aonidiella aurantii Maskell), el piojo gris (Parlatoria pergandei Comstock) y serpeta gruesa (Lepidosaphes beckii Newman). Su tratamiento mediante plaguicidas tradicionales es en ocasiones poco efectivo debido a la biología de la plaga y a las crecientes restricciones en cuanto al número de plaguicidas disponibles, por lo que un posible tratamiento de esta plaga basado en su feromona sexual tendría un alto interés. Hasta el momento la síntesis de la feromona sexual de A. nerii, identificada por Einhorn et al. en 1998 como acetato de 2-[(1R,2S)-cis-2-isopropenil-1-(4¿-metil-4¿-pentenil)-ciclobutano]etilo, ha sido llevada a cabo por diversos autores pero las rutas sintéticas descritas para obtener esta feromona, presentan un elevado número de etapas sintéticas y un rendimiento global bajo, no resultando adecuadas para llevarlas a escala multigramo. Se puede destacar la síntesis de Einhorn et al., en 1998, que involucra 17 etapas y un rendimiento global de 0.40% o la síntesis total desarrollada por ese mismo año por Guerrero et al. con 15 etapas y un rendimiento global de 5.6%. Por estas razones, en la presente tesis se aborda el desarrollo de una ruta sintética que mejore las existentes para obtener la feromona sexual del piojo blanco del limón (A. nerii) a escala multigramo. La ruta sintética desarrollada en este trabajo parte de sustratos comerciales de bajo coste como el 3-hidroxipropanonitrilo, el cual puede ser transformado en la feromona de interés empleando únicamente 10 etapas y con un rendimiento global de 10.3%, con procedimientos de purificación sencillos y mediante diversas reacciones que incluyen como reacciones clave una reacción de tipo Blaise y una fotocicloadición de tipo [2+2]. Asimismo, algunos de los intermedios sintéticos obtenidos en esta ruta propuesta son de alto interés para mejorar las síntesis de las feromonas de agregación de Diaprepes abbreviatus Linnaeus y de Trypodendron lineatum Olivier, las cuales representan plagas importantes en diferentes países. La posibilidad de obtener cantidad suficiente de la feromona sexual de A. nerii, ha permitido la realización de ensayos en campo, y se espera generar un aporte significativo en el desarrollo de técnicas alternativas para el control de esta plaga en cultivos de interés en España y en otros países. / L'ús de les feromones sexuals d'insectes per a la detecció, seguiment i control de plagues ha anat creixent de manera constant en els darrers anys, convertint aquestes substàncies en una de les eines més importants en la lluita contra poblacions d'insectes dins el Control Integrat de Plagues, ajudant així a reduir la quantitat i l'ús de plaguicides convencionals. L'aplicació d'aquestes tècniques fa necessària l'obtenció d'aquestes substàncies mitjançant síntesi orgànica. El poll blanc de la llimona Aspidiotus nerii Bouché, 1833, també conegut com poll del baladre (Oleander scale), és una plaga cosmopolita i polífaga que ataca més de 100 famílies de plantes. A Espanya constitueix una plaga de còccids d'importància mitjana en el cultiu de cítrics després del poll roig de Califòrnia (Aonidiella aurantii Maskell), el poll gris (Parlatoria pergandei Comstock) i serpeta gruixuda (Lepidosaphes beckii Newman). El seu tractament mitjançant plaguicides tradicionals en ocasions és poc efectiu a causa de la biologia de la plaga i a les creixents restriccions pel que fa al nombre de plaguicides disponibles, de manera que un possible tractament d'aquesta plaga basat en la seua feromona sexual tindria un alt interès. Fins al moment la síntesi de la feromona sexual d'A. nerii, identificada per Einhorn et al. el 1998 com a acetat de 2-[(1R,2S)-cis-2-isopropenil-1-(4'-metil-4'-pentenil)-ciclobutàn]etil, ha estat portada a terme per diversos autors però les rutes sintètiques descrites per obtenir aquesta feromona, presenten un elevat nombre d'etapes sintètiques i un rendiment global baix, no resultant adequades per al pas a escala multigram. Es pot destacar la síntesi de Einhorn et al., El 1998, que involucra 17 etapes i un rendiment global de 0,40% o la síntesi total desenvolupada per aquest mateix any per Guerrero et al. amb 15 etapes i un rendiment global de 5.6%. Per aquestes raons, en la present tesi s'aborda el desenvolupament d'una ruta sintètica que millore les existents per obtenir la feromona sexual del poll blanc de la llimona (A. nerii) a escala multigram. La ruta sintètica desenvolupada en aquest treball parteix de substrats comercials de baix cost com el 3-hidroxipropanonitril, el qual pot ser transformat en la feromona d'interès emprant únicament 10 etapes i amb un rendiment global de 10.3%, amb procediments de purificació senzills i mitjançant diverses reaccions que inclouen com a reaccions clau una reacció de tipus Blaise i una fotocicloaddició de tipus [2 + 2]. Així mateix, alguns dels intermedis sintètics obtinguts en aquesta ruta proposada són d'alt interès per millorar les síntesis de les feromones d'agregació de Diaprepes abbreviatus Linnaeus i de Trypodendron lineatum Olivier, les quals representen plagues importants en diferents països. La possibilitat d'obtenir quantitat suficient de la feromona sexual d'A. nerii, ha permès la realització d'assajos en camp, i s'espera generar una aportació significativa en el desenvolupament de tècniques alternatives per al control d'aquesta plaga d'importància en cultius d'interès en Espanya i en altres països. / Montaño Castañeda, MC. (2017). DESARROLLO DE UNA RUTA SINTÉTICA PARA LA OBTENCIÓN DE LA FEROMONA SEXUAL DEL PIOJO BLANCO DEL LIMÓN (Aspidiotus nerii) [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/92184 / TESIS

Hydrogen peroxide (H2O2) is a reactive oxygen species generated by several metabolic pathways in mammalian cells. Endothelial cells are extremely susceptible to oxidative stress. H2O2 has been reported to increase the permeability in these cells. Using rat heart endothelial cell culture as a model system, we examined the effect of H2O2 on the gene expression of vascular endothelial growth factor (VEGF), a potent mitogen of endothelial cells and a vascular permeability factor. By Northern blot analysis we found that VEGF mRNA responded to H2O2 in a dose-and time- dependent manner. The induction was superinduced by cycloheximide and blocked by actinomycin D. N-Acetylcysteine, a synthetic antioxidant, was able to suppress the induction. H7, a protein kinase C inhibitor, could also block the induction. Electrophoretic mobility shift assay revealed an enhanced binding of transcription factors, AP-1 and NF-κB. Immunoblot analysis showed that the amount of secreted VEGF was elevated in the medium 4 h after H2O2 stimulation. Our results demonstrate that VEGF gene expression is upregulated by H2O2 in these endothelial cells.

<p>Total synthesis of massarinolin A, purpurlides B, D, E, 2,3-deoxypurpurolide C, phleghenrines A and B were finished. A halogen bond promoted michael addiation was discovered during mechanism study toward diamination of allenes. Computational chemsitry study conducted toward the selectivity of 2+2 reaction supported the proposed key reaction during total synthesis of gibberellic acid 18.</p>

Neste trabalho é apresentada a síntese e a caracterização de cinco novas iminas derivadas de compostos do tipo 2-(2`-hidroxifenil)benzazóis, fluorescentes devido a um mecanismo de transferência protônica intramolecular no estado excitado (ESIPT). Estas iminas foram caracterizadas por espectroscopia de absorção na região do infravermelho (IV) e por espectroscopia de ressonância magnética nuclear de hidrogênio (1H-RMN) e apresentaram deslocamentos de Stokes compatíveis com compostos que sofrem o mecanismo de ESIPT. Os produtos apresentaram sensível variação do máximo de emissão de fluorescência devido à reação de protonação em meio ácido, o que permite seu uso como sensores ópticos de pH. Ensaios demonstraram que as iminas sintetizadas são sensíveis à presença de Ni2+ devido à reação de complexação com o metal, causando uma alteração do máximo de emissão de fluorescência. / The present work presents the synthesis and characterization of five new imines derived from 2-(2`-hydroxyphenyl)benzazole derivatives, fluorescent due to an excited state intramolecular proton transfer (ESIPT) mechanism. These imines were characterized by infrared absorption spectroscopy (IR) and by hydrogen-1 nuclear magnetic resonance spectroscopy (1H-NMR) and presented Stokes shifts compatible with ESIPT compounds. These products presented a considerable shift of the maximum fluorescence emission due to the protonation reaction in acid medium, which allows their use as pH optical sensors. Tests showed that the synthesized imines are sensitive to Ni2+ due to the complexation reaction with the metal, causing a shift of the maximum fluorescence emission.