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Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are naturally produced in aquatic ecosystems e.g. by algae. Many OH-PBDEs have been observed to be highly bioactive and to cause adverse effects through several pathways, e.g. via disrupting oxidative phosphorylation (OXPHOS). The levels of some OH-PBDEs have increased in Baltic biota over the past decades. This may be associated with the nutrient enrichment of the Baltic Sea, which has favored growth of some of the OH-PBDE producers. Ceramium tenuicorne has been suggested to be a producer of OH-PBDEs in the Baltic Sea, which is supported by the results presented in this thesis. The levels of OH-PBDEs were observed to fluctuate greatly in C. tenuicorne over the summer season, and to correlate with the levels of pigments in the algae. However, the observed congener pattern in C. tenuicorne questioned theories regarding the mechanism of their biosynthesis. The results indicate a much more selective pathway for biosynthesis than previously suggested for the production of OH-PBDEs. One of the most abundant OH-PBDEs in C. tenuicorne, 6-OH-BDE137, has previously been observed to be toxic to bacteria, fungi, and crustaceans. Furthermore, Baltic gammarids seemed to change their feeding preferences towards less grazing on C. tenuicorne during the production peek of OH-PBDEs in the alga. This suggests that OH-PBDEs may serve as allelochemical defense agents for C. tenuicorne. The transport and fate of OH-PBDEs through a Baltic food chain was also studied, including C. tenuicorne, Gammarus spp., three-spined stickleback (Gasterosteus aculeatus), and perch (Perca fluviatilis). A small portion of the OH-PBDEs were observed to be methylated in the alga, or by associated bacteria. The methylated OH-PBDEs biomagnified in the food chain up to perch, in which they were converted back to the OH-PBDEs via demethylation. The OH-PBDEs and their methylated counterparts were also partially debrominated in the food chain, which resulted in high concentration of 6-OH-BDE47 in the perch. This congener is the most toxic OH-PBDE with regards to OXPHOS disruption. Another biotransformation of OH-PBDEs was identified in Baltic Sea blue mussels (Mytilus edulis). High concentrations of OH-PBDEs were conjugated with lipophilic moieties, e.g. fatty acids. This increases the residence time of the OH-PBDEs in the mussels. Mussels have been suggested to conjugate steroids with fatty acids as a means to regulate hormone levels. The conjugation of OH-PBDEs to fatty acids may occur due to intrusion into this pathway. Methods were developed to include quantification of conjugated OH-PBDEs in the analysis of mussels. OH-PBDEs were also quantified in blood from Baltic Sea grey seals (Halichoerus grypus). Seals originating from the Baltic proper were observed to be more highly exposed to 6-OH-BDE47 than seals from the Gulf of Bothnia. However, the levels of OH-PBDEs were generally low. A major effort was invested into securing these results, including development of a new analytical method. Blood obtained from dead seals is a difficult matrix for quantification of OH-PBDEs, and previous attempts using an established method yielded unsatisfactory results. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>

Ce mémoire décrit les travaux qui ont été réalisés sur la synthèse de l’hodgsonox, un sesquiterpène tricyclique comportant un éther diallylique dans un cycle tétrahydropyranique. Les approches envisagées sont la formation du cycle à cinq puis la formation du tétrahydropyrane et une autre plus convergente qui implique la synthèse des deux cycles en une seule étape. La première partie du mémoire discute de la synthèse d’un précurseur acyclique du cycle à cinq membres, afin de réaliser une réaction de métathèse de fermeture de cycle. Toutefois, les essais n’ont pas été concluants et cette voie a été abandonnée. Dans la deuxième partie, une nouvelle approche impliquant la synthèse d’un bicycle par une réaction de Pauson-Khand a été étudiée. Le précurseur de la réaction de Pauson- Khand a été préparé en 9 étapes (30% de rendement global) à partir du diéthyle tartrate. Le produit de cyclisation a été également obtenu mais il n’a pas été possible par la suite d’introduire le groupement isopropyle. Dans la dernière partie de ce mémoire, les travaux de Lise Brethous sur la synthèse de l’hodgsonox ont été repris. Celle-ci avait montré que le cycle à 5 membres pouvait être obtenu à partir de l’a-acétyl g-butyrolactone et que la formation du bicycle pouvait être réalisée par une réaction catalytique d’insertion d’un composé diazoïque dans un lien O-H. Certaines de ces étapes ont été optimisées et différents tests ont été effectués pour réaliser les dernières étapes de la synthèse de l’hodgosonox, mais sans succès. / This master thesis describes various strategies towards the total synthesis of (+)- and (-)-hodgsonox, a tricyclic sesquiterpene containing a diallylic ether functionality fused into a tetrahydropyran ring. The first synthetic approach involved the formation of the fivemembered ring followed by the formation of the tetrahydropyran moiety. The second approach consisted in the synthesis of both carbon cycles in a single stage. In the first part, is described the synthesis of an acyclic precursor to assemble the fivemembered ring via a ring-closing metathesis reaction. This approach proved unsuccessful and was not pursued. In the second part, is reported a Pauson-Khand cyclization to produce the bicyclic compound. The Pauson-Khand precursor was synthesized in 9 steps (30% overall yield) from diethyl tartarate. The cyclization was successful, but the isopropyl moiety could not be introduced. A former Lebel’s PhD student, Lise Brethous had also worked on the total synthesis of hodgsonox. She established that the 5-membered ring could be prepared from a-acetyl gbutyrolactone and observed the formation of the tetrahydropyran moiety via an OH-insertion reaction with a diazo intermediate. In the last part of this master thesis, some steps from Brethous’s approach were optimized. Unsuccessful attempts to tackle the last steps of the synthesis are also described.

Approved for public release, distribution is unlimited / For over half a century the NPS Aerolabʼ Low Speed Wind Tunnel located in Halligan Hall of the Naval Postgraduate school has served to provide students and faculty with meaningful aerodynamic data for research and problem analysis. New data acquisition hardware was installed three years ago but never fully verified, and contained no integrated software program to collect data from the strain-gauge balance pedestal. Existing National Instruments based hardware for the NPS low-speed wind tunnel was reconfigured to obtain data from the strain-gauge pedestal. Additionally, a data acquisition software program was written in LabVIEW⠭ to accommodate the hardware. The Virtual Instruments (VI) program collects and plots accurate data from all four strain gauges in real-time, producing non-dimensional force and moment coefficients. A research study on the performance of an OH-6A helicopter fuselage was conducted. NPS Aerolabʼ wind tunnel tests consisted of drag, lift, and pitching moment measurements of the OH-6A along yaw and angle-of-attack sweeps. The results of the NPS wind tunnel data were compared against testing conducted on a full-scale OH-6A helicopter in NASA Ames' 40 ft. x 80ft. wind tunnel, along with the U.S. Army's Light Observation Helicopter (LOH) wind tunnel tests. Results of current testing substantiate the LabVIEW⠭ code. / Ensign, United States Navy

[pt] Automorfismos genéricos de cubos com alças (handlebodies) aparecem do estudo de classes the isotopia de automorfismos de variedades orientáveis de dimensão três. Automorfismos genéricos permanecem como uma das partes menos entendidas desse estudo.Dado um automorfismo genérico de um cubo com alças, é conhecida uma forma de se construir uma laminação bidimensional que é invariante pelo automorfismo. A essa laminação se associa um fator de crescimento. É sabido que, no caso de tal fator de crescimento ser minimal - uma característica importante, pois mede a complexidade essencial do automorfismo - a laminação deve gozar de uma certa propriedade de incompressibilidade. Nessa tese mostramos que o processo de se achar uma laminação com tal propriedade é algoritmico. Por outro lado, mostramos que tal propriedade não garante que o respectivo fator de crescimento seja minimal. Propomos uma outra propriedade, tensão transversal, mais forte que incompressibilidade, que conjecturamos também ser condição necessária para que o fator de crescimento seja minimal. Provamos a conjectura em alguns casos.Além dos resultados mencionados acima, desenvolvemos métodos para gerar automorfismos genéricos de cubos com alcas, que usamos para apresentar alguma variedade de exemplos. / [en] Generic automorphisms of handlebodies appear naturally in the study of isotopy classes of automophisms of orientable three-dimensional manifolds. Generic automorphisms remain as one of the least understood parts of this study. Given a generic automorphism of a handlebody one can construct a bidimensional lamination that is invariant under the automorphism. There is a growth rate associated to this lamination. It is known that, when this growth rate is minimal among all possible choices (an important property, for it measures the essential complexity of the automorphism), the lamination must have a certain incompressibility property. On this thesis we show that the process of finding a lamination with such a property is algorithmic. On the other hand, we show that this said incompressibility property is not sufficient for the minimality of the growth rate. We propose a stronger property, which we called transverse tightness, and conjecture that it is a necessary condition for the growth rate to be minimal. We prove the conjecture in some particular cases. In addition to the results mentioned above, we develop methods to generate generic automorphisms of handlebodies, which we use to present some variety of examples.

A hiperplasia adrenal congênita (HAC) é um grupo de doenças hereditárias causadas por uma deficiência em uma das enzimas necessárias para a síntese de cortisol no cortex adrenal. Mais de 95% de todos os casos de HAC são devidos a 21-Hidroxilase (21-OHD). Existem 3 formas principais, duas com manifestações clínicas no período neonatal, a forma mais grave perdedora de sal (HAC-PS) e a forma virilizante simples (HAC-VS). Além da perda salina, o excesso de andrógenos leva à virilização de recém nascidas femininas. As formas neonatais são chamadas de clássicas, atividade enzimática da 21-OH bastante reduzida, de < 2% na HAC-PS e de 2-10% na HAC-VS. A forma parcial de início tardio é chamada de HAC não clássica (HAC-NC) e a principal manifestação na infância é a adrenarca precoce. Nesta forma a atividade da 21-OH é de 20-60%. Os programas de triagem para HAC visam, principalmente, ao diagnóstico precoce da forma clássica perdedora de sal, mais grave e potencialmente letal. No Brasil, a triagem pública é realizada no Estado de Goiás desde 1997 e em Santa Catarina desde 2001. No Rio Grande do Sul (RS) foi implantada em maio de 2014 na fase IV do Programa Nacional de Triagem Neonatal. A inclusão da HAC trouxe consigo muitos desafios e a exigência de um fluxo de triagem e diagnóstico bem estruturados. O diagnóstico precoce é crucial para prevenir o óbito de lactentes por insuficiência adrenal. Dosa-se, em papelfiltro, a 17OH progesterona (17-OHP). Elevações podem ocorrer em recém-nascidos sem HAC (falso-positivos), devido a situações de estresse perinatal e por prematuridade. Após avaliação dos dados do primeiro ano de triagem para HAC neste estudo, a mediana da idade da coleta nos casos diagnosticados foi de 8 dias (4.25-15.75). Dos 8 casos diagnosticados de maio de 2014 a abril de 2015, 6 casos com forma perdedora de sal (incluindo 1 caso de óbito por coleta tardia do TP aos 38 dias de vida). A incidência encontrada em nosso meio no primeiro ano foi de 1:13.551 casos. Com a estratégia do uso de pontos de corte estratificados pelo peso de nascimento18, o índice total de resultados positivos em nosso meio foi de 0,5% da amostra avaliada (“n” total de 514 bebês), sendo mais frequente em recém nascidos com menos de 2000g de peso ao nascer. Além da confirmação clínica e laboratorial, o genótipo é importante, além de confirmar, para estabelecer gravidade da doença e também para ratificar o diagnostico dos falsos positivos na ausência de uma mutação do gene CYP21A2. Um dos casos confirmados de HAC-PS foi associado a múltiplas malformações e craniossinostose severa, suscitando a hipótese de um a associação com defeito de FGFR2. A correlação genótipo- fenótipo na avaliação dos casos em dois anos da triagem alcançou um alto nível de concordância de 87%. Diagnosticada, portanto, de forma assertiva a HAC forma clássica, instituise a terapia glicocorticóide para as formas virilizante simples e acrescenta-se mineralocorticóide para as formas perdedoras de sal. A triagem neonatal é um importante programa de saúde populacional e visa ao diagnóstico precoce de uma patologia com potencial risco à vida pela perda de sal, além de permitir adequada atribuição de sexo nas meninas com virilização genital e à saúde da criança. Estabelecer os fluxos adequados de triagem e manejo, além de ampliar o conhecimento sobre a HAC, com o reconhecimento dos desfechos e tratamentos adequados é essencial para minimizar as possíveis complicações nesta população de maior vulnerabilidade. / Congenital adrenal hyperplasia (CAH) is a group of inherited diseases caused by a deficiency in one of the enzymes required for the cortisol synthesis by the adrenal cortex. More than 95% of all CAH cases are due to 21-hydroxylase (21-OHD). There are 3 forms, two with neonatal clinical manifestation: salt-wasting CAH (SW-CAH\) and the simple virilizing form (HAC-VS). In addition to salt loss, androgens excess lead to the virilization of female newborn. Neonatal forms are defined as classical CAH. The 21-OHD enzymatic activity in SWCAH is less than <2% and in the SV-CAH 2-10%. A late-onset form, with partial enzymatic defect (20-60%) is called non-classical HAC (NC-CAH) and the main manifestation in childhood is early adrenarche. In Brazil, public health screening has been conducted in the State of Goiás since 1997 and in te Sate of Santa Catarina since 2001. In Rio Grande do Sul (RS) it was implemented in May 2014, in phase IV of the National Neonatal Screening Program. The inclusion of CAH in the local screening program brought many challenges and the need of a well structured screening and diagnosis flowchart. Early diagnosis is crucial to prevent infant death due to adrenal insufficiency. Around de world, the screening programs for CAH main purpose is the early diagnosis of the more severe classical forms, especially SW-CAH. The cortisol precursor 17OH progesterone (17-OHP) is the main disease marker and is measured on filter paper. Elevations may occur in infants without CAH (false positive) due to perinatal stress and prematurity. Of newborns screened in the first year, median age of collection in diagnosed cases was 8 days (4.25-15.75) and 8 patients were diagnosed with CAH (four males, four females). The incidence of CAH in the state was 1:13,551. Six cases were identified as classic salt-was-ting CAH and two were cases of virilizing CAH. The overall rate of positive results was 0.5% (n = 514 infants). The number of false positive results was higher among newborns with birth weight < 2,000 g. In addition to clinical and laboratory confirmation, the genotype is important to confirme 21-OH deficiency, to establish disease severity and also in the absence of a mutation of the CYP21A2 gene to more precise exclude the diagnosis of suspected false positives. One of the confirmed cases of SW-CAH was associated with multiple malformations and severe craniosynostosis, raising the hypothesis of an association with FGFR2 mutation. A high genotype- phenotype correlation of 87% was found in the cases after two years of screening. Once the classic CAH is diagnosed, glucocorticoid therapy is instituted and mineralocorticoid is added for SW-CAH. CAH neonatal screening is an important population health program and aims to the early diagnosis of a pathology with a potential risk due to salt loss crisis. The early detection of cases also allows to adequate sex assignment in girls with genital virilization. Establishing adequate screening flows, proper diagnosis and management, in addition to increase knowledge about the disease, with the appropriate recognition of outcomes and treatments is essential to minimize complications in this population of greater vulnerability.

Les techniques de mesures optiques non intrusives développées depuis plusieurs dizaines d'années permettent la mesure des paramètres physiques tels que la température, la concentration des espèces chimiques et la vitesse. Tous ces diagnostics optiques, bien que très performants, sont généralement appliqués en mesures ponctuelles.<br />Le but de la thèse est de développer une ou plusieurs techniques d'imagerie quantitatives et instantanées de température et de concentration. Deux axes d'études complémentaires ont été abordés au cours de ce travail. Il s'agit de la fluorescence induite par laser sur le radical OH pour l'étude des milieux en combustion et de la fluorescence induite par laser d'un traceur moléculaire (acétone) pour l'étude des écoulements non réactifs. Ces deux axes d'étude ont été menés en parallèle avec la même approche : après compilation des données bibliographiques, des modèles de fluorescence induite par laser de ces deux espèces ont été développés. Les résultats de ces modélisations ont servi à sélectionner les meilleures stratégies expérimentales. <br />Des expériences pilotes ont été mises en place en vue développer ces techniques d'imagerie. Elles consistent en l'utilisation des modèles proposés pour les deux traceurs étudiés afin d'obtenir des images instantanées et couplées de température et de concentration dans différents types d'écoulements (combustion hydrogène–air, mélange de jets, ...). <br />D'autres applications ont été réalisées sur des bancs d'essais à caractère semi-industriel afin de caractériser l'utilisation de ces techniques dans des conditions de mesures sévères. <br />Les résultats obtenus au cours de ces différentes expériences montrent que l'outil d'imagerie quantitative et instantanée développé est opérationnel, répondant ainsi à un besoin d'informations quantitatives et spatialement résolues et complétant les possibilités offertes par les autres diagnostics optiques.

The foci of this thesis are the metal oxides Cu2O, ZnO and Fe3O4 and their interaction with water and sulfur dioxide (SO2). The intention is to study SO2-induced atmospheric corrosion on a molecular level. All studies are based on photoelectron spectroscopy (PES) and scanning tunneling microscopy (STM) measurements. The band structure of Cu2O in the Γ-M direction has been probed by angle-resolved PES (ARPES). It reveals a more detailed picture of the bulk band structure than earlier data and gives the first experimental evidence of a dispersive hybridized Cu 3d-Cu 4s state. The experimental data is compared to band structure calculations. The structure of clean metal oxide surfaces and impact of sample preparation have been studied. Oxygen vacancies can form a (√3x√3)R30° reconstruction on Cu2O(111). Oxygen atoms adjacent to copper vacancies, steps or kinks are shown to be adsorption sites for both water and SO2. Annealing temperature influences the defect density and hydrogen content in ZnO, which can have large impact on the surface properties of ZnO(0001). Water is shown to adsorb dissociatively on ZnO(0001) and partly dissociatively on Cu2O(111). The dissociation occurs at undercoordinated oxygen sites on both surfaces. Water stays adsorbed on ZnO(0001) at room temperature but on Cu2O(111), all water has desorbed at 210 K. SO2 interacts with one or two undercoordinated O-sites on all studied oxide surfaces forming SO3 or SO4 species respectively. SO4 on Fe3O4(100) follows the (√2x√2)R45° reconstruction. On Cu2O(111) and ZnO(0001), SO2 adsorbs on defect sites. An SO3 to SO4 transition is observed on Cu2O(111) when heating an SO3 adsorbate layer from 150 K to 280K. Coadsorption of water and SO2 on ZnO(0001) and Fe3O4(100) has been studied briefly. Water blocks SO2 adsorption sites on ZnO(0001). On Fe3O4(100) and on one type of reduced ZnO(0001) sample, SO2 dissociation to atomic sulfur or sulfide occurs to a higher extent on water exposed surfaces than on clean surfaces. Water thus appears to increase the charge density on some surfaces. Further studies are needed to reveal the cause of this unexpected effect. / <p>QC 20110516</p>

Die Arbeit enthaelt kurze Abrisse zum gegenwertigen Kenntnisstand bezueglich der Struktur und der Eigenschaften von amorphen Siliciumdioxiden sowie zur Erzeugung von Silan- und Phenylgruppen auf Siliciumdioxidoberflaechen. Im Mittelpunkt der Arbeit steht die Oberflaechenfunktionalisierung des Aerosil 300 aus der Gasphase bei hohen Temperaturen. Es wird die Reaktion des Wasserstoffs mit den Silanolgruppen zu Silangruppen und deren Umsetzung mit Benzol untersucht. Die IR-Spektroskopie wird zur Verfolgung des Einflusses der Reaktionsparameter (Temperatur, Zeit und Volumenstroeme der Gase) auf das Ergebnis der Funktionalisierung eingesetzt. Neben der IR-Spektroskopie wird auch die Festkoerper-NMR-Spektroskopie zur Strukturaufklaerung genutzt. Weiterhin werden die erzeugten Oberflaechengruppen quantitativ bestimmt und die molaren dekadischen Extinktionskoeffizienten fuer die Valenzschwingung der Silangruppen bei 2293 cm-1 und der Phenylgruppen bei 3068 cm-1 berechnet. Die Hydrolysebestaendigkeit sowie die thermische Stabilitaet der Oberflaechensilane und -phenyle wird ueberprueft. Außerdem werden Aussagen zu den Eigenschaften der Oberflaechen-Si-H-Bindung getroffen. Dann wird gezeigt, daß auch auf Kieselgeloberflaechen Silan- und Phenylgruppen erzeugt werden koennen.