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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.
41

Neuroanatomical variability in individuals with alcohol use disorder : A systematic review

Lundqvist, Roosa, Deramond, Jenny January 2024 (has links)
Alcohol Use Disorder (AUD) is a pervasive and intricate public health challenge, with significant health and psychosocial consequences. Among the most frequently used substances, alcohol provokes diverse neurochemical and neurophysiological changes within the brain and is in long-term excessive use associated with severe cognitive dysfunctions such as memory, decision-making, and problem-solving abilities. This systematic review aims to compare gray matter volume in healthy individuals and those diagnosed with AUD, with the goal of identifying structural differences between the two groups. The six studies, identified from Scopus, Web of Science, and Medline EBSCO, included in this systematic review were written in English, published within the last 20 years, employed magnetic resonance imaging (MRI) to quantify volume, involved human participants over the age of 18, and included both AUD and healthy comparison groups examining gray matter volume differences. The number of participants and gender distribution differed among all the included articles, with two studies exclusively including males. The studies employed either region of interest (ROI) or voxel-based morphometry (VBM) as their analysis method. The results revealed gray matter reductions between individuals with AUD and those without through out the whole brain, both cortical and subcortical, with the most prominent reductions observed in the putamen and thalamus. Future research should consider the limitations presented in this systematic review by conducting longitudinal investigations focusing on gray matter reductions and recovery over extended periods. Such studies could offer deeper insights into how the brain's gray matter volume behaves during longer periods of abstinence among individuals with AUD.
42

As estâncias missioneiras da Banda Oriental do Rio Uruguai

Serres, Helenize Soares 06 July 2018 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2018-10-16T16:14:13Z No. of bitstreams: 1 Helenize Soares Serres_.pdf: 9790971 bytes, checksum: abda03b30a0495bcc3a5a822accae61a (MD5) / Made available in DSpace on 2018-10-16T16:14:13Z (GMT). No. of bitstreams: 1 Helenize Soares Serres_.pdf: 9790971 bytes, checksum: abda03b30a0495bcc3a5a822accae61a (MD5) Previous issue date: 2018-07-06 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / Esta tese estuda as estâncias missioneiras da Banda Oriental do Rio Uruguai na primeira metade do século XVIII. O trabalho investiga as articulações que elas mantiveram com suas respectivas reduções e também com outros atores sociais daquele espaço. As estâncias foram, em boa medida, responsáveis pelo sustento das reduções, uma vez que a criação de gado foi essencial à alimentação de suas populações, situação que as tornava diretamente responsáveis pela viabilidade das missões. Por isso, ao falar em espaço missioneiro, é preciso considerar tais áreas não “urbanas” como parte importante a que se refere. As estâncias apresentavam, entre suas estruturas, postos com currais, ranchos, galpões e capelas, sendo habitadas por um número de indígenas que variava durante o ano. Considerando isso, o texto aborda as dinâmicas de sua formação e organização, os trabalhos e trabalhadores que faziam parte de sua rotina, bem como as relações que, a partir delas, se estabeleciam com grupos de indígenas não reduzidos, colonos espanhóis e portugueses. Interessa ainda os litígios em que se envolveram as estâncias entre si e com os povoados missioneiros, bem como a forma como estes casos eram resolvidos. Esse estudo se baseou na leitura da literatura de referência e na análise intensiva de um conjunto variado de fontes jesuíticas tais como: memoriais, diários de padres, pareceres, cartas, processos de litígios, crônicas e mapas. Ao lado delas, foram consultados documentos procedentes da administração espanhola e diários dos administradores que assumiram os pueblos após a expulsão dos jesuítas. Por meio desse material, a tese busca elucidar a importância alcançada pelas estâncias, uma vez que se constituem como uma parte essencial da própria redução. / This thesis studies the missionary ranchs (estancias) of the Eastern Band of the Uruguay River in the first half of the 18th century. The work investigates the articulations that they maintained with their respective reductions and also with other social actors within that space. The ranches were, to a large extent, responsible for sustaining the reductions, since cattle farming was essential to feed their populations, which made them directly responsible for the viability of the missions (missiones). Therefore, when speaking in missions‟ space, it is necessary to consider such non-"urban" areas as an important part to which it refers. The estancias had corrals, ranches, sheds and chapels among their structures, being inhabited by several natives whose number varied during the year. Considering this, the text addresses the dynamics of its formation and organization, the tasks and workers that were part of its routine, as well as the relations that, from them, established themselves with groups of indiscriminate indigenous, Spanish and Portuguese settlers. It also interests the litigations amid the estancias themselves and also with the mission villages, as well as the way these cases were fixed. This study was based on the reading of the literature of reference and the intensive analysis of a varied set of Jesuit sources such as: memorials, diaries of priests, opinions, letters, litigation processes, chronicles and maps. Next to them, were consulted documents from the Spanish administration and diaries of the administrators who took over the pueblos after the expulsion of the Jesuits. Through this material, the thesis seeks to elucidate the importance reached by the estancias, since they constitute an essential part of the reductions.
43

Asymmetric Hydrogenations of Imines, Vinyl Fluorides, Enol Phosphinates and Other Alkenes Using N,P-Ligated Iridium Complexes

Diesen, Jarle Sidney January 2008 (has links)
The research described in this thesis is directed toward the efficient, enantioselective synthesis of chiral products that have useful functionality. This goal was pursued through catalytic asymmetric hydrogenation, a reaction class that selectively introduces one or two stereocenters into a molecule in an atom-efficient step. This reaction uses a small amount (often <1 mol%) of a chiral catalyst to impart stereoselectivity to the product formed. Though catalytic asymmetric hydrogenation is not a new reaction type, there remain many substrate classes for which it is ineffective. The present thesis describes efforts to extend the reaction to some of these substrates classes. Some of the products synthesized in these studies may eventually find use as building blocks for the production of chiral pharmaceuticals, agrochemicals, or flavouring or colouring agents. However, the primary and immediate aim of this thesis was to develop and demonstrate new catalysts that are rapid and effective in the asymmetric hydrogenation of a broad range of compounds. Paper I describes the design and construction of two new, related chiral iridium compounds that are catalysts for asymmetric hydrogenation. They each contain an N,P-donating phosphinooxazoline ligand that is held together by a rigid bicyclic unit. One of these iridium compounds catalyzed the asymmetric hydrogenation of acyclic aryl imines, often with very good enantioselectivities. This is particularly notable because acyclic imines are difficult to reduce with useful enantioselectivity. The second catalyst was useful for the asymmetric hydrogenation of two aryl olefins. In Paper II, the class of catalysts introduced into Paper I is expanded to include many more related compounds, and these are also applied to the asymmetric hydrogenation of prochiral imines and olefins. By studying a range of related catalysts that differ in a single attribute, we were able to probe how different parts of the catalyst affect the yield and selectivity of the hydrogenation reactions. Whereas iridium catalysts had been applied to the asymmetric hydrogenation of imines and largely unfunctionalized olefins prior to this work (with varied degrees of success), they had not been used to reduce fluoroolefins. Their hydrogenation, which is discussed in Paper III, was complicated by concomitant defluorination to yield non-halogenated alkanes. To combat this problem, several iridium-based hydrogenation catalysts were applied to the reaction. Two catalysts stood out for their ability to produce chiral fluoroalkanes in good enantioselectivity while minimizing the defluorination reaction, and one of these bore a phosphinooxazoline ligand of the type described in Papers I and II. Enol phosphinates are another class of olefins that had not previously been subjected to iridium-catalyzed asymmetric hydrogenation. They do, however, constitute an attractive substrate class, because the product chiral alkyl phosphinates can be transformed into chiral alcohols or chiral phosphines with no erosion of enantiopurity. Iridium complexes of the phosphinooxazoline ligands described in Papers I and II were extremely effective catalysts for the asymmetric hydrogenation of enol phosphinates. They produced alkyl phosphinates from di- and trisubstituted enol phosphinate, β-ketoester-derived enol phosphinates, and even purely alkyl-substituted enol phopshinates, in very high yields and enantioselectivities.
44

Linear degeneracy in multidimensions

Moss, Jonathan January 2016 (has links)
Linear degeneracy of a PDE is a concept that is related to a number of interesting geometric constructions. We first take a quadratic line complex, which is a three parameter family of lines in projective space P3 specified by a single quadratic relation in the Plucker coordinates. This complex supplies us with a conformal structure in P3. With this conformal structure, we associate a three-dimensional second order quasilinear wave equation. We show that any PDE arising in this way is linearly degenerate, furthermore, any linearly degenerate PDE can be obtained by this construction. We classify Segre types of quadratic complexes for which the structure is conformally flat, as well as Segre types for which the corresponding PDE is integrable. These results were published in [1]. We then introduce the notion of characteristic integrals, discuss characteristic integrals in 3D and show that, for certain classes of second-order linearly degenerate dispersionless integrable PDEs, the corresponding characteristic integrals are parameterised by points on the Veronese variety. These results were published in [2].
45

Méthodes de sous-espaces de Krylov rationnelles pour le contrôle et la réduction de modèles / Rational Krylov subspace methods for the control and model reductions

Abidi, Oussama 08 December 2016 (has links)
Beaucoup de phénomènes physiques sont modélisés par des équations aux dérivées partielles, la discrétisation de ces équations conduit souvent à des systèmes dynamiques (continus ou discrets) dépendant d'un vecteur de contrôle dont le choix permet de stabiliser le système dynamique. Comme ces problèmes sont, dans la pratique, de grandes tailles, il est intéressant de les étudier via un autre problème dérivé réduit et plus proche du modèle initial. Dans cette thèse, on introduit et on étudie de nouvelles méthodes basées sur les processus de type Krylov rationnel afin d'extraire un modèle réduit proche du modèle original. Des applications numériques seront faites à partir de problèmes pratiques. Après un premier chapitre consacré au rappel de quelques outils mathématiques, on s'intéresse aux méthodes basées sur le processus d'Arnoldi rationnel par blocs pour réduire la taille d'un système dynamique de type Multi-Input/Multi-Output (MIMO). On propose une sélection adaptative de choix de certains paramètres qui sont cruciaux pour l'efficacité de la méthode. On introduit aussi un nouvel algorithme adaptatif de type Arnoldi rationnel par blocs afin de fournir une nouvelle relation de type Arnoldi. Dans la deuxième partie de ce travail, on introduit la méthode d'Arnoldi rationnelle globale, comme alternative de la méthode d'Arnoldi rationnel par blocs. On définit la projection au sens global, et on applique cette méthode pour approcher les fonctions de transfert. Dans la troisième partie, on s'intéresse à la méthode d'Arnoldi étendue (qui est un cas particulier de la méthode d'Arnoldi rationnelle) dans les deux cas (global et par blocs), on donnera quelques nouvelles propriétés algébriques qui sont appliquées aux problèmes des moments. On consièdère dans la quatrième partie la méthode de troncature balancée pour la réduction de modèle. Ce procédé consiste à résoudre deux grandes équations algébriques de Lyapunov lorsque le système est stable ou à résoudre deux équations de Riccati lorsque le système est instable. Comme ces équations sont de grandes tailles, on va appliquer la méthode de Krylov rationnel par blocs pour approcher la solution de ces équations. Le travail de cette thèse sera cloturé par une nouvelle idée, dans laquelle on définit un nouvel espace sous le nom de sous-espace de Krylov rationnelle étendue qui sera utilisée pour la réduction du modèle. / Many physical phenomena are modeled by PDEs. The discretization of these equations often leads to dynamical systems (continuous or discrete) depending on a control vector whose choice can stabilize the dynamical system. As these problems are, in practice, of a large size, it is interesting to study the problem through another one which is reduced and close to the original model. In this thesis, we develop and study new methods based on rational Krylov-based processes for model reduction techniques in large-scale Multi-Input Multi-Output (MIMO) linear time invariant dynamical systems. In chapter 2 the methods are based on the rational block Arnoldi process to reduce the size of a dynamical system through its transfer function. We provide an adaptive selection choice of shifts that are crucial for the effectiveness of the method. We also introduce a new adaptive Arnoldi-like rational block algorithm to provide a new type of Arnoldi's relationship. In Chapter 3, we develop the new rational global Arnoldi method which is considered as an alternative to the rational block Arnoldi process. We define the projection in the global sense, and apply this method to extract reduced order models that are close to the large original ones. Some new properties and applications are also presented. In chapter 4 of this thesis, we consider the extended block and global Arnoldi methods. We give some new algebraic properties and use them for approaching the firt moments and Markov parameters in moment matching methods for model reduction techniques. In chapter 5, we consider the method of balanced truncation for model reduction. This process is based on the soluytions of two major algebraic equations : Lyapunov equations when the system is stable or Riccati equations when the system is unstable. Since these equations are of large sizes, we will apply the rational block Arnoldi method for solving these equations. In chapter 6, we introduce a new method based on a new subspace called the extended-rational Krylov subspace. We introduce the extended-rational Krylov method which will be used for model reduction in large-scale dynamical systems.
46

Idiom-driven innermost loop vectorization in the presence of cross-iteration data dependencies in the HotSpot C2 compiler / Idiomdriven vektorisering av inre loopar med databeroenden i HotSpots C2 kompilator

Sjöblom, William January 2020 (has links)
This thesis presents a technique for automatic vectorization of innermost single statement loops with a cross-iteration data dependence by analyzing data-flow to recognize frequently recurring program idioms. Recognition is carried out by matching the circular SSA data-flow found around the loop body’s φ-function against several primitive patterns, forming a tree representation of the relevant data-flow that is then pruned down to a single parameterized node, providing a high-level specification of the data-flow idiom at hand used to guide algorithmic replacement applied to the intermediate representation. The versatility of the technique is shown by presenting an implementation supporting vectorization of both a limited class of linear recurrences as well as prefix sums, where the latter shows how the technique generalizes to intermediate representations with memory state in SSA-form. Finally, a thorough performance evaluation is presented, showing the effectiveness of the vectorization technique.
47

The Local Economic Impact of Alternative State Budget Reductions for Selected Texas Community Colleges

Saleh, Abdelrahim 05 1900 (has links)
The purpose of this study was to determine the local economic impact of alternative state budget reductions for Texas community colleges by investigating the income losses to the Metropolitan Statistical Areas (MSAs) if state appropriations were reduced by 10, 15, and 20 percent. The objective of this study was achieved through an economic analysis of the local economy of selected MSAs and by computing the income size which was generated by selected colleges. Eight community colleges located in eight MSAs participated by answering mailed questionnaires. The model of Direct Economic Impact was applied to describe the colleges' economic impact. The model was composed of college expenditures, employee expenditures, student expenditures, and the economic multiplier. The study revealed that the selected community colleges were responsible for creating new jobs and increasing the income of the local economies. These eight colleges were responsible for increasing the income of the local economies by $294,945,560 and for creating 5,129 jobs. Reduction in state appropriations to the selected community colleges will reduce the income they produce. A state appropriation cut of 10 percent will result in a loss to the local economy of $6,153,951. A 15 percent reduction in state appropriations will cause the local economy to lose $9,230,943. A 20 percent reduction in state appropriations will reduce the local economic income by $12,307,920.
48

Las reducciones de capital por absorción de pérdidas y sus efectos en el costo computable de accionistas no domiciliados / Capital reductions for loss absorption and their effects on the computable cost of non-domiciled shareholders

León Puccio, Pablo Antonio 06 1900 (has links)
En nuestro medio, los sujetos no domiciliados que deciden vender sus acciones de empresas peruanas deben realizar un procedimiento de certificación de capital invertido ante la Administración tributaria. Sin embargo, hasta el momento, esta ha ajustado el costo computable de las acciones de titularidad de los sujetos no domiciliados cuando las empresas peruanas emisoras de tales acciones han realizado reducciones de capital para absorber pérdida. De este modo, la presente investigación tiene como objeto determinar si las reducciones de capital para absorber pérdidas deberían implicar una disminución del costo computable de las acciones de las empresas peruanas que son enajenadas por sujetos no domiciliados.
49

PART 1: SYMPHONY NO. 1: THE SLEEP SYMPHONYPART 2: SYMMETRY AND FORM IN CHRISTOPHER ROUSE'S FLUTE CONCERTO

Miller, Kevin 21 May 2019 (has links)
No description available.
50

Environmental impact from materials and products in infrastructure / Miljöpåverkan från material och produkter inom bygg- och anläggningsbranschen

Bergman, Alexander January 2021 (has links)
Global uppvärmning och klimatförändringar har enat världens länder och det arbetas hårt för att den globala temperaturökningen ska hållas under 2 °C. I EU har man satt som mål att vara klimatneutrala senast 2050 och i Sverige satte man ett ambitiöst mål på att uppnå nettonollutsläpp redan till 2045. I och med det satte även bygg- och anläggningsbranschen som mål att vara klimatneutrala till år 2045. För att nå målet måste alla aktörer i branschen ta sitt ansvar och hitta nya mer miljövänliga alternativ och lösningar. Syftet med denna studie var att sammanställa totala mängder och utsläppta koldioxidekvivalent för tio nyckelprodukter och material använda i tillbyggnaden i projektet Nya Krav Himmerfjärdsverket som utfördes av Veidekke Entreprenad AB. Dessutom att identifiera möjliga miljövänligare alternativ till dessa produkter för att till sist undersöka möjligheten av poängtagning i hållbarhetscertifieringen CEEQUAL i avsnitt 7.2.1, 7.2.3, 7.3.1 samt 7.3.2. Mängddata samlades in från upphandlade avtal, aktuella protokoll samt projektets samordningsmodell. GWP-data som användes som underlag för produkternas utsläpp insamlades från produktspecifika EPD:er. Resultaten fastslog att de produkter som var kopplade till störst utsläpp i projektet var betong, Multicem, betongpålar, armeringsjärn och prefabricerade betongelement. Det konstaterades att utsläppen kopplade till betong kunde minskas med upp till 26,7% genom användning av betong med iblandad flygaska. Utförda utsläppsbesparing i projektet beräknades till 2399 ton CO2e och möjliga utsläppsbesparingar för projektet beräknades till 750 ton CO2e. Jämfört med baseline-utsläpp uppnåddes en reducering på 32%. Totalt uppskattades poängtagning för CEEQUAL i avsnitten 7.2.1, 7.2.3, 7.3.1 samt 7.3.2 till mellan 66–125 poäng. Slutsatser som drogs ur studien var vikten av att redan från starten av bygg- och anläggningsprojekt börja tänka på miljö- och hållbarhetsfrågor och däribland produkt- och materialval. / Global warming and climate change have united the world. There is ongoing hard work to keep global temperature rise below 2 ° C. In the EU, the goal has been to be climate neutral by 2050 and, in Sweden, an ambitious goal has been set to achieve net-zero emissions by 2045. Because of this, the construction industry has also set a goal of being climate neutral by 2045. To achieve the goal all players in the industry must take their responsibility and find new, more environmentally friendly alternatives and solutions. The purpose of this study was to compile total amounts and emitted carbon dioxide equivalent for ten key products and materials used in the new extension of the Nya Krav Himmerfjärdsverket project carried out by Veidekke Entreprenad AB. Also, to identify more environmentally friendly alternatives to these products. Finally, the study investigated the possibility of scoring in sustainability certification CEEQUAL in sections 7.2.1, 7.2.3, 7.3.1 and 7.3.2. Quantity data was collected from procured agreements, current protocols, and the project's coordination model. GWP data was used as the basis for product emissions and were collected from product-specific EPDs.The results stated that the products that were linked to the largest emissions in the project were concrete, Multicem, concrete piles, rebar, and prefabricated concrete elements. It was found that emissions linked to concrete could be reduced by up to 26.7% using concrete with fly ash. Emissions savings that had been made in the project were estimated at 2399 tonnes of CO2e and possible emission savings for the project were estimated at 750 tonnes of CO2e. Compared to the baseline emissions, a total reduction of 32% was achieved. In total, scoring for CEEQUAL in sections 7.2.1, 7.2.3, 7.3.1 and 7.3.2 was estimated at between 66–125 points. Conclusions drawn from the study were the importance of starting to think about environmental and sustainability issues, including product and material choices, right from the start of construction and infrastructure projects.

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