>Magister Scientiae - MSc / As the demand for energy is constantly increasing, researchers are looking at various methods of energy production. Following the rise of solar energy becoming a major player, researchers are looking at kesterite materials, Cu2ZnSn(S,Se)4 (CZTS) for photovoltaic applications as they demonstrate many excellent characteristics making them highly suitable for use in thin-film solar cells. Consequently, there are major drawbacks of using kesterite materials for photovoltaic applications such as their point defects and secondary phases. Cerium and iron oxyselenides (Ce2O2Fe2OSe2) are a member of the chalcogenide family and by introducing this chalcogenide into the kesterite structure there would be an improvement in the semiconducting property of the kesterite material. The focus of this research is to dope the kesterite material with nanoscopic cerium and iron oxyselenides in order to reduce the band gap of the kesterite material, thereby improving its light absorption, thus, resulting in a more efficient photovoltaic effect.

The parkinsonian inducing drug 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is bioactivated in a reaction catalyzed by the flavoenzyme monoamine oxidase B (MAO-B) to form the corresponding dihydropyridinium (MPDP+) subsequently pyridinium (MPP+) metabolites. As part of our ongoing studies to characterize the structural features responsible for this unexpected biotransformation, we have synthesized and examined the MAO-B substrate properties of a variety of MPTP analogs bearing various heteroaryl groups at the 4-position of the tetrahydropyridinyl ring. The results of these SAR studies indicate that electronic features, steric features and polar interactions can contribute to the substrate activities. Additionally, isotope effects have been examined to investigate the mechanism and stereoselectivity of the MAO-B catalytic pathway. The synthesis and characterization of regio and stereoselectively deuterated MPTP analogs have been achieved. The results indicate that the catalytic step occurs exclusively at the allylic C-6 position and is rate-determining for both good and poor substrates. The two enantiomers of MPTP bearing a deuterium atom at C-6 have been prepared via chiral aminooxazolinyl derivatives and have been characterized by 2H NMR in a chiral liquid crystal matrix. These enantiomers were used to determine the selectivity of the MAO-B catalyzed a C-H bond cleavage reaction leading to the dihydropyridinium metabolite MPDP+. Some of the cyclopropyl analogs of MPTP have also been synthesized as the potential inhibitors. / Ph. D.

Informed forest management requires accurate, up-to-date information. Ground-based forest inventory is commonly conducted to generate estimates of forest characteristics with a predetermined level of statistical confidence. As the importance of monitoring forest resources has increased, budgetary and logistical constraints often limit the resources needed for precise estimates. In this research, the incorporation of ancillary information in planted loblolly pine (Pinus taeda L.) forest inventory was investigated. Additionally, a simulation study using synthetic populations provided the basis for investigating the effects of plot and stand-level inventory aggregations on predictions and projections of future forest conditions. Forest regeneration surveys are important for assessing conditions immediately after plantation establishment. An unmanned aircraft system was evaluated for its ability to capture imagery that could be used to automate seedling counting using two computer vision approaches. The imagery was found to be unreliable for consistent detection in the conditions evaluated. Following establishment, conditions are assessed throughout the lifespan of forest plantations. Using small area estimation (SAE) methods, the incorporation of light detection and ranging (lidar) and thinning status improved the precision of inventory estimates compared with ground data alone. Further investigation found that reduced density lidar point clouds and lower resolution elevation models could be used to generate estimates with similar increases in precision. Individual tree detection estimates of stand density were found to provide minimal improvements in estimation precision when incorporated into the SAE models. Plot and stand level inventory aggregations were found to provide similar estimates of future conditions in simulated stands without high levels of spatial heterogeneity. Significant differences were noted when spatial heterogeneity was high. Model form was found to have a more significant effect on the observed differences than plot size or thinning status. The results of this research are of interest to forest managers who regularly conduct forest inventories and generate estimates of future stand conditions. The incorporation of auxiliary data in mid-rotation stands using SAE techniques improved estimate precision in most cases. Further, guidance on strategies for using this information for predicting future conditions is provided. / Doctor of Philosophy / Informed forest management requires accurate, up-to-date information. Groundbased sampling (inventory) is commonly used to generate estimates of forest characteristics such as total wood volume, stem density per unit area, heights, and regeneration survival. As the importance of assessing forest resources has increased, resources are often not available to conduct proper assessments. In this research, the incorporation of ancillary information in planted loblolly pine (Pinus taeda L.) forest inventory was investigated. Additionally, a simulation study investigated the effects of two forest inventory data aggregation methods on predictions and projections of future forest conditions. Forest regeneration surveys are important for assessing conditions immediately after tree planting. An unmanned aircraft system was evaluated for its ability to capture imagery that could be used to automate seedling counting. The imagery was found to be unreliable for use in accurately detecting seedlings in the conditions evaluated. Following establishment, forest conditions are assessed at additional points in forest development. Using a class of statistical estimators known as small-area estimation, a combination of ground and light detection and ranging data generated more confident estimates of forest conditions. Further investigation found that more coarse ancillary information can be used with similar confidence in the conditions evaluated. Forest inventory data are used to generate estimates of future conditions needed for management decisions. The final component of this research found that there are significant differences between two inventory data aggregation strategies when forest conditions are highly spatially variable. The results of this research are of interest to forest managers who regularly assess forest resources with inventories and models. The incorporation of ancillary information has potential to enhance forest resource assessments. Further, managers have guidance on strategies for using this information for estimating future conditions.

A common problem encountered in phased array signal processing is how to remove sources of interference from a desired signal. Two existing methods to accomplish this are the Linearly Constrained Minimum Variance (LCMV) beamformer and the Side-Lobe Canceller (SLC). LCMV provides better performance than SLC, but comes with much higher computational costs. The Steered Auxiliary Beam Canceller (SABC) presented in this thesis is a new algorithm developed to improve the performance of SLC without the computational costs of LCMV. SABC performs better than SLC because it uses high-gain auxiliary channels for cancellation. This new technique is now possible because digital arrays allow for direction finding algorithms such as Estimation of Signal Parameters via Rotational Invariance Techniques (ESPRIT) to estimate the directions of the interference sources. With this added knowledge, high gain beams similar to the main beam may be used as auxiliaries instead of low-gain antenna elements. Another contribution is a method introduced to calculate the computational complexity of LCMV, SLC, and SABC much more accurately than existing methods which only provide order-of-magnitude estimates. The final contribution is a derivation of the signal loss experienced by SLC and SABC and simulations that verify the performance of LCMV, SLC, and SABC. / Master of Science

Pusiau pagalbinio veiksmažodžio vaidmuo šiuolaikinėje prancūzų kalboje semantikos ir sintaksės požiūriu yra labai ženklus, nes pusiau pagalbiniai veiksmažodžiai yra dažni ir grožinėje literatūroje, ir dokumentiniame žanre, ir buityje. Kalbininkų požiūris į pusiau pagalbinius veiksmažodžius skiriasi tik dėl paties pavadinimo: pusiau pagalbiniai, veikslo, pagalbiniai veikslo veiksmažodžiai, modaliniai veiksmažodžiai, veiksmažodžių junginiai, tačiau visi kalbininkai sutaria, kad pagalbiniai veiksmažodžiai prancūzų kalboje skiriasi nuo pagalbinių veiksmažodžių tuo, kad jie išsaugo didesnę ar mažesnę semantinės reikšmės dalį ir padeda išreikšti tuos niuansus, kurių neįmanoma išreikšti morfologinėmis formomis. Tai ir yra pusiau pagalbinių veiksmažodžių vaidmuo semantikos požiūriu. Sintaksės požiūriu pusiau pagalbiniai veiksmažodžiai sudaro nedalomą junginį su tariniu, todėl yra sudėtinė tarinio dalis, kuri paklūsta visoms tradicinės gramatikos taisyklėms: yra asmenuojama, kaitoma laikais, asmenimis, derinama su skaičiumi, gimine ir tt. / Semi-auxiliary verb's role in modern French syntax and semantics is very significant because the semi-auxiliary verbs are quite frequent in literature as well as periodicals. All the linguists agree on the fact, that auxiliary verbs or pure modals do not contain any semantic meaning and serve just for grammatical purposes to express future or past times and semi-auxiliary verbs in French do contain some part of its semantic meaning and have some serious impact on the main verb. Linguists’ approaches differ only in the denomination as a semi-auxiliary or auxiliary of aspect, auxiliary aspect verbs, modal verbs, verbs compounds and so on. The semi-auxiliary verbs role consists of its semantic sens as well as its syntactic functions, as semi-auxiliary verbs tend to express the shadings of a verb, that can’t be translated by morphological means and morphological forms. On the syntactic point of view, semi-auxiliary verbs form with the infinitive an integrated combination of the predicate. It is an integral part of the predicate, where the semi-auxiliary acts as a regular verb under all rules of grammar: changes in accordance with person, singular or plural, gender, mode, time etc. / Le rôle du verbe semi-auxiliaire dans le français contemporain du point de vue sémantico- syntaxique est très important, puisque les verbes semi auxiliaires sont fréquents en belles lettres ainsi que les périodiques et le quotidien. Les approches des linguistes envers le verbe semi-auxiliaire ne diffèrent qu’en dénomination : semi-auxiliaire, auxiliaire d’aspect, les aspectuels, les modaux, causatifs, perceptifs, périphrases verbales etc. Tous les linguistes soulignent que le verbe auxiliaire est dépourvu de tout sens, et le verbe semi-auxiliaire en garde une partie sémantique plus ou moins grande. Les semi-auxiliaires aident à exprimer les nuances quand les formes morphologiques ne peuvent pas les couvrir. Le verbe semi-auxiliaire est étroitement lié à l’expression de l’aspect. Le rôle sémantique des verbes semi-auxiliaires consiste à apporter des nuances au verbe principal ou même détourner son sens, tandis que le rôle syntaxique est plus concret et consiste à précéder et faire partie intégrante du prédicat et .

Nätverks-RTK (Real-Time Kinematic) är en metod för positionsbestämning med Global Navigation Satellite System (GNSS) i realtid. Metoden kräver att en driftledningscentral kan kommunicera med de GNSS-mottagare som använder referensstationsnätet, för att bland annat skicka ut korrigerade GNSS-data. I Sverige erbjuder SWEPOS, ett nät av fasta referensstationer, en tjänst för nätverks-RTK-mätning, som förväntas ge en mätosäkerhet på mindre än 15 mm i plan och 25 mm i höjd (över ellipsoiden) (med täckningsfaktorn k = 1 i bägge fallen). Den teknik som idag används av SWEPOS för att utföra positionsbestämning av GNSS-mottagare är Virtuell Referensstation (VRS). VRS kräver tvåvägskommunikation eftersom mottagaren skickar in sin absoluta position till nätverks-RTK-programvaran hos driftledningscentralen, var beräkningarna av korrektionsdata sker, innan de skickas tillbaka till mottagaren. Det finns ett annat alternativ som möjliggör envägskommunikation, nämligen nätverks-RTK-meddelande. Då sänds observationsdata, i form av korrektioner, ut till mottagaren som utför positionsberäkningarna. Syftet med det här examensarbetet var att undersöka nätverks-RTK-meddelande för GNSS-mottagare av tre olika fabrikat med avseende på initialiseringstider, mätosäkerhet, avståndsberoende från närmaste masterstation, och GLONASS-satelliters deltagande i positionsbestämningen. I studien ingick även att utföra några jämförande mätningar med VRS. Undersökningarna gjordes genom upprepade nätverks-RTK-mätningar med GNSS-mottagare från Leica Geosystems, Trimble och Topcon, på tre kända punkter sydöst om Gävle. Tre mätmetoder användes, nätverks-RTK-meddelande med automatiskt nät (tvåvägskommunikation) och statiskt nät (envägskommunikation), samt VRS. De tre mätpunkterna valdes så att avståndet, till den referensstation som användes som en så kallad masterstation, varierade. Studien visade att initialiseringstiderna skiljde mellan de tre mottagarfabrikaten. En anledning till detta var att varje mottagare ominitialiserades från olika lösningslägen. Generellt var mätosäkerheten något högre för statiskt nät. Mätosäkerheten var omkring 11 mm i plan och 19 mm i höjd med det automatiska nätet, samt 13 mm respektive 22 mm i det statiska nätet. Fabrikaten emellan, låg Leica och Trimble på samma nivå, medan Topcon hade ett generellt problem för det statiska nätet, vilket det inte fanns möjlighet att närmare utreda orsaken till. Resultatet visade även att mätosäkerheten påverkas av avståndet till använd masterstation. I några fall var dessa förhållanden linjära. Vid några tillfällen användes inte GLONASS-satelliter i positionsbestämningen. / Network RTK (Real-Time Kinematic) is a method of positioning with Global Navigation Satellite System (GNSS) in real-time. The method requires that a control centre can communicate with the GNSS receiver, which is using the reference station network, for example to send out corrected GNSS data. In Sweden, SWEPOS, which is a network of permanent reference stations for GNSS, offers a service for Network RTK measurement. This is expected to give an uncertainty of less than 15 mm in plane and 25 mm in (ellipsoidal) height (with the coverage factor k = 1 in both cases). The technology currently used by SWEPOS, to perform positioning of a GNSS receiver, is Virtual Reference Station (VRS). VRS requires two-way communication because the receiver submits its navigated location to the control centre, where the calculations of correction data are made, before they are sent back to the receiver. Another alternative is Network RTK messages which make use of one-way communication. Then the observation data are transmitted to the receiver, which performs determination of its position. The purpose of this thesis was to investigate the network RTK messages with GNSS receivers from three different manufacturers with regard to time to fix ambiguities, measurement uncertainty and its dependence on the distance from the master station, and GLONASS satellites presence in the positioning. Also included in the study was the performance of comparative measurements with VRS. The investigations were conducted through repeated network RTK measurements with GNSS receivers from Leica Geosystems, Trimble and Topcon, at three known points south-east of Gävle. Three methods were used, network RTK message with automatic and static networks, and VRS. The three measurement points were chosen so that the distance to the reference station that was used as the so-called master station, varied. The study showed that the time to fix ambiguities differed between the three brands. One reason for this was that each receiver was reinitialized from different steps in the initialization process. In general, the uncertainty in the measurement was slightly higher for the static network. The uncertainty was about 11 mm in plane and 19 mm in height with the automated network, and 13 mm and 22 mm respectively in the static network. Leica and Trimble were at the same level, while Topcon had general problems for the static network, which there was no possibility to closer investigate the reason for. The results also showed that the uncertainty is influenced by the distance to used master station. In some cases, this relationship is linear. On some occasions, GLONASS satellites were not included in the positioning.

The first chapter provides some basic definitions and results from the theory of convex analysis and nonlinear mappings related to our work. Some sufficient conditions for the existence of a solution of problem (GVIP) are also recalled. In the second chapter, we first illustrate the scope of the auxiliary problem procedure designed to solve problems like (GVIP) by examining some well-known methods included in that framework. Then, we review the most representative convergence results for that class of methods that can be found in the literature in the case where F is singlevalued as well as in the multivalued case. Finally, we somewhat discuss the particular case of projection methods to solve affine variational inequalities. The third chapter introduces the variational convergence notion of Mosco and combines it with the auxiliary problem principle. Then, we recall the convergence conditions existing for the resulting perturbed scheme before our own contribution and we comment them. Finally, we introduce and illustrate the rate of convergence condition that we impose on the perturbations to obtain better convergence results. Chapter 4 presents global and local convergence results for the family of perturbed methods in the case where F is singlevalued. We also discuss how our results extend or improve the previous ones. Chapter 5 studies the multivalued case. First, we present convergence results generalizing those obtained when there is no perturbations. Then, we relax the scheme by means of a notion of enlargement of an operator and we provide convergence conditions for this inexact scheme. In Chapter 6, we build a bundle algorithm to solve problem (GVIP) and we study its convergence.

L'oxazolidine trifluorométhylée (trans-Fox) dérivée du (R)-phénylglycinol a été préparée sous forme diastéréoisomériquement pure par résolution dynamique induite par la cristallisation d'un mélange d'oxazolidines cis et trans.La trans-Fox a été utilisée avec succès comme auxiliaire chiral pour des réactions d'hydroxylation par l'oxygène moléculaire et de fluoration électrophile d'énolates d'amide ainsi qu'en réarrangement sigmatropique [2,3] d'amines allyliques. Après clivage, des composés énantiomériquement purs d'une grande importance synthétique sont obtenus.Une voie d'accès à des pyrrolydines trifluorométhylées chirales a été mise au point à partir de la trans-Fox. La trans 2-phenyl-5-trifluoromethylpyrrolidine a été utilisée comme auxiliaire chiral pour des réactions d'alkylation asymétriques. / The trifluoromethylated oxazolidine (trans-Fox) derived from (R)-phenylglycinol was prepared as a single diastereoisomer by a cristallisation induced dynamic resolution of a mixture of cis and trans oxazolidines.The trans-Fox was used with success as a chiral auxiliary for hydroxylation by oxygen and electrophilic fluorination of amide enolates reactions and [2,3] sigmatropic rearrangements of allylic amines. After deprotection, very synthetically useful enantiomerically pure compounds were obtained.An acces to chiral trifluoromethylated pyrrolidines was developped starting from trans-Fox. The trans 2-phenyl-5-trifluoromethylpyrrolidine was used as a chiral auxiliary for asymmetric alkylation reactions.

Les récepteurs du glutamate de type AMPA (rAMPA) sont les récepteurs ionotroniques responsables de la majeure partie des courants excitateurs rapides lors de la transmission synaptique dans le système nerveux central. Le nombre de rAMPA stabilisés à la synapse est responsable en partie de l’intensité de la transmission synaptique et de nombreux phénomènes de plasticité synaptique. Les rAMPA se répartissent en trois populations en équilibre dynamique: les récepteurs intracellulaires, les récepteurs extra-synaptiques, et les récepteurs synaptiques stabilisés au niveau de la densité post-synaptique. L’implication des protéines transmembranaires régulatrices des rAMPA (TARP) dans la stabilisation des rAMPA est établie, et repose au moins en partie sur la liaison de la protéine TARP γ-2 avec la protéine d’échafaudage PSD-95. Dans l’hippocampe, siège de nombreux phénomènes de plasticité, l’isoforme γ-8 est particulièrement enrichie. La TARP γ-8 a pour particularité de posséder un domaine C-terminal plus long que son homologue γ-2 et de s’exprimer au niveau synaptique et extra-synaptique. Mon travail de thèse à consisté à étudier les mécanismes moléculaires mis en jeu dans la régulation de la liaison des protéines TARP γ-2 et γ-8 avec la protéine PSD-95, ainsi que l’implication respective des deux isoformes dans la régulation de la mobilité latérale des rAMPA. Les résultats majeurs de cette étude sont : a) l’interaction entre γ-2 et PSD-95 est régulée par la longueur apparent du domaine C-terminal de γ-2 modulée par la phosphorylation; b) γ-8 lie PSD-95 dans les compartiments synaptiques et extra-synaptiques, toutefois cette interaction n’est pas corrélée avec une immobilisation des rAMPA. Ces résultats suggèrent que γ-2 et γ-8 jouent des rôles bien distincts dans l’adressage des rAMPA à la synapse. / AMPA type glutamate receptors (AMPARs) are ionotropic receptors responsible for most excitatory transmission in the central nervous system. The number of stabilized AMPARs in front of glutamate release sites determines in large part the strength of synaptic transmission and variation in this number is thought to underlie numerous forms of synaptic plasticity. AMPARs are present in three main subcellular pools between which they are in a dynamic equilibrium by processes of trafficking: intracellular receptors, extrasynaptic receptors, and synaptic receptors stabilized at the postsynaptic density (PSD). Transmembrane AMPAR regulatory proteins (TARPs) are known to be implicated in AMPAR stabilization at the synapse through the interaction of TARP γ-2/8 with the scaffolding protein PSD-95. In the hippocampus, a structure exhibiting various synaptic plasticity patterns, γ-8 is the most abundant TARP. This isoform is characterized by a longer C-terminal fragment than γ-2 and a synaptic and extrasynaptic localization. During my Ph.D, I studied the molecular mechanisms involved in the regulation of TARP γ-2 and γ-8 binding to PSD-95 and their respective roles in regulating AMPAR lateral mobility. The main results are: a) γ-2 interaction with PSD-95 is regulated by the apparent length of its C-terminus domain that is modulated by phosphorylation; b) γ-8 binds PSD-95 in synaptic and extrasynaptic compartment however this interaction is not correlated with AMPAR immobilization. Altogether, those results suggest that those two TARP isoforms have independent functional roles.

Master of Science / Department of Electrical and Computer Engineering / William B. Kuhn / The design of power amplifiers in any semi-conductor process is not a trivial exercise and it is often encountered that the simulated solution is significantly different than the results obtained. Oscillatory phenomena occurring either in-band or out of band and sometimes at subharmonic intervals can render a design useless. Other less apparent effects such as jumps, hysteresis and continuous spectrum, often referred to as chaos, can also invalidate a design. All of these problems might have been identified through a more rigorous approach to stability analysis. Designing for stability is probably the one area of amplifier design that receives the least amount of attention but incurs the most catastrophic of effects if it is not performed properly. Other parameters such as gain, power output, frequency response and even matching may have suitable mitigation paths. But the lack of stability in an amplifier has no mitigating path. In addition to the loss of the design there are the increased production cycle costs, costs involved with investigating and resolving the problem and the costs involved with schedule slips or delays resulting from it. The Linville or Rollett stability criteria that many microwave engineers follow and rely exclusively on is not sufficient by itself to ensure a stable and robust design. It will be shown that the belief that unconditional stability is obtained through an analysis of the scattering matrix S to determine if K>1 and [delta][supscript]s<1 can fail and other tools must be used to validate circuit stability. With the emphasis being placed on stability, a 1W pulse modulated S-band power amplifier is designed using a battery of analysis tools in addition to the standard Linville or Rollett criteria to rigorously confirm the stability of the circuit. Test measurements are then presented to confirm the stability of the design and illustrate the results. The research shown contributes to the state of the art by offering a detailed approach to stability design and then applying the techniques to the design of a 1W pulse modulated S-band power amplifier demonstrating the first with 20 nanosecond pulse width switching and single digit nanosecond rise and fall times at 1 Watt power levels.