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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

SPECTROSCOPIC AND MECHANISTIC STUDIES OF METALLO-BETA-LACTAMASE INHIBITORS AND THE STRUCTURE-FUNCTION RELATIONSHIP OF NEW DELHI METALLO-BETA-LACTAMASE VARIANTS

Bergstrom, Alexander R. 20 April 2018 (has links)
No description available.
42

MODELING HETEROTACHY IN PHYLOGENETICS

Zhou, Yan 04 1900 (has links)
Il a été démontré que l’hétérotachie, variation du taux de substitutions au cours du temps et entre les sites, est un phénomène fréquent au sein de données réelles. Échouer à modéliser l’hétérotachie peut potentiellement causer des artéfacts phylogénétiques. Actuellement, plusieurs modèles traitent l’hétérotachie : le modèle à mélange des longueurs de branche (MLB) ainsi que diverses formes du modèle covarion. Dans ce projet, notre but est de trouver un modèle qui prenne efficacement en compte les signaux hétérotaches présents dans les données, et ainsi améliorer l’inférence phylogénétique. Pour parvenir à nos fins, deux études ont été réalisées. Dans la première, nous comparons le modèle MLB avec le modèle covarion et le modèle homogène grâce aux test AIC et BIC, ainsi que par validation croisée. A partir de nos résultats, nous pouvons conclure que le modèle MLB n’est pas nécessaire pour les sites dont les longueurs de branche diffèrent sur l’ensemble de l’arbre, car, dans les données réelles, le signaux hétérotaches qui interfèrent avec l’inférence phylogénétique sont généralement concentrés dans une zone limitée de l’arbre. Dans la seconde étude, nous relaxons l’hypothèse que le modèle covarion est homogène entre les sites, et développons un modèle à mélanges basé sur un processus de Dirichlet. Afin d’évaluer différents modèles hétérogènes, nous définissons plusieurs tests de non-conformité par échantillonnage postérieur prédictif pour étudier divers aspects de l’évolution moléculaire à partir de cartographies stochastiques. Ces tests montrent que le modèle à mélanges covarion utilisé avec une loi gamma est capable de refléter adéquatement les variations de substitutions tant à l’intérieur d’un site qu’entre les sites. Notre recherche permet de décrire de façon détaillée l’hétérotachie dans des données réelles et donne des pistes à suivre pour de futurs modèles hétérotaches. Les tests de non conformité par échantillonnage postérieur prédictif fournissent des outils de diagnostic pour évaluer les modèles en détails. De plus, nos deux études révèlent la non spécificité des modèles hétérogènes et, en conséquence, la présence d’interactions entre différents modèles hétérogènes. Nos études suggèrent fortement que les données contiennent différents caractères hétérogènes qui devraient être pris en compte simultanément dans les analyses phylogénétiques. / Heterotachy, substitution rate variation across sites and time, has shown to be a frequent phenomenon in the real data. Failure to model heterotachy could potentially cause phylogenetic artefacts. Currently, there are several models to handle heterotachy, the mixture branch length model (MBL) and several variant forms of the covarion model. In this project, our objective is to find a model that efficiently handles heterotachous signals in the data, and thereby improves phylogenetic inference. In order to achieve our goal, two individual studies were conducted. In the first study, we make comparisons among the MBL, covarion and homotachous models using AIC, BIC and cross validation. Based on our results, we conclude that the MBL model, in which sites have different branch lengths along the entire tree, is an over-parameterized model. Real data indicate that the heterotachous signals which interfere with phylogenetic inference are generally limited to a small area of the tree. In the second study, we relax the assumption of the homogeneity of the covarion parameters over sites, and develop a mixture covarion model using a Dirichlet process. In order to evaluate different heterogeneous models, we design several posterior predictive discrepancy tests to study different aspects of molecular evolution using stochastic mappings. The posterior predictive discrepancy tests demonstrate that the covarion mixture +Γ model is able to adequately model the substitution variation within and among sites. Our research permits a detailed view of heterotachy in real datasets and gives directions for future heterotachous models. The posterior predictive discrepancy tests provide diagnostic tools to assess models in detail. Furthermore, both of our studies reveal the non-specificity of heterogeneous models. Our studies strongly suggest that different heterogeneous features in the data should be handled simultaneously.
43

Caracterização sérica da lectina ligadora de manose (MBL) em indivíduos portadores de parasitoses intestinais

ALENCAR, Maria de Nazaré Costa Santos January 2012 (has links)
Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2017-09-28T15:15:11Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_CaracterizacaoSericaLectina.pdf: 842856 bytes, checksum: 1d50a60868eedc792b1a123a56c45874 (MD5) / Approved for entry into archive by Irvana Coutinho (irvana@ufpa.br) on 2017-10-06T12:06:36Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_CaracterizacaoSericaLectina.pdf: 842856 bytes, checksum: 1d50a60868eedc792b1a123a56c45874 (MD5) / Made available in DSpace on 2017-10-06T12:06:37Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_CaracterizacaoSericaLectina.pdf: 842856 bytes, checksum: 1d50a60868eedc792b1a123a56c45874 (MD5) Previous issue date: 2012 / Apesar de as parasitoses intestinais, serem conhecidas desde muito tempo e serem estudas desde sua identificação, ainda constituem um desafio quanto ao seu diagnóstico e tratamento. Existe a necessidade de investimentos em pesquisas para o diagnóstico mais preciso, para a pronta intervenção, para os casos existentes. Além da prevenção dos fatores de risco que favorecem o surgimento, a manutenção e a propagação desses agentes. O conhecimento de que a competência imunológica do hospedeiro é um fator limitante da carga parasitária de diversas espécies. Considerando-se que a lectina ligadora de manose (MBL), componente do sistema do complemento, é uma proteína chave do sistema imune inato, atuando na primeira linha de defesa contra os patógenos pois é considerada de fase aguda, este estudo com 221 amostras de indivíduos de ambos os sexos e idades variadas, coletadas em três laboratórios distintos, no período de janeiro a abril de 2012. Foi estabelecido o perfil da população do estudo e fez-se a análise da associação entre fatores sociais e demográficos com as entero-parasitoses e avaliada a influência dos níveis séricos da lectina ligadora de manose(MBL) na susceptibilidade das enteroparasitoses, distribuição por faixa etária e sexo. Estabelecida também a comparação entre as concentrações séricas de MBL dos grupos com identificação de parasitas. Foram observadas associações estatisticamente significativas quando se relacionou os protozoários E.histolytica e G.lamblia com a concentração sérica da MBL. / Although the intestinal parasitosis are known since a long time and be studied since its identification, still constitute a challenge for their diagnosis and treatment. The delineation of the problem coming up in the necessity of investments in research for more accurate diagnosis, for the prompt intervention, to the existing cases and work for the prevention of risk factors that favor the emergence, maintenance and propagation of these agents. The knowledge that the host's immune competence is a limiting factor of parasitic load of various species, stimulated the research considering that the Mannosebinding lectin (MBL), a component of the complement system, is a key protein of the innate immune system, acting in the first line of defense against pathogens because it is considered acute phase. In this study, were colected 221 samples of individuals of both gender and varied ages at three different laboratories, in the period from January to April 2012. The profile of the population of the study are made and the analysis of the association between social and demographic factors with the entero-parasites and evaluated the influence of serum levels of Mannose-binding lectin (MBL) susceptibility of enteroparasitoses, distribution by age group and gender. Established also the comparison between serum concentrations of MBL of groups with identification of parasites. Statistically significant associations were observed when related protozoa E. histolytica and G.lamblia with the serum concentration of the MBL.
44

Utstationering av utländska arbetstagare i Sverige : Är Lex Britannia och Sveriges sätt att implementera utstationeringsdirektivet (96/71/EG) förenliga med EG-rätten?

Sanfridsson, Karin January 2005 (has links)
<p>The Latvian building company Laval un Partneri Ltd (Laval) posted Latvian construction workers at the rebuilding of a school in Vaxholm in autumn 2004. Because the company refused to sign a collective agreement with Svenska Byggnadsarbetareförbundet (Byggnads), which is the Swedish trade union for constructions workers, Byggnads put the construction site under a boycott. Next Laval sued Byggnads for damages in the Swedish Labour Court (AD) because Laval considers the boycott as well as Byggnad´s demand that Laval signs a collective agreement incompatible with EC Law. AD has now demanded a preliminary ruling from the European Court of Justice (ECJ). While waiting for the preliminary ruling from the ECJ, several important questions of principle stand unanswered. Two such questions are whether Lex Britannia and the way in which Sweden har implemented the directive for posted workers (96/71/EC) are compatible with EC Law. In this thesis the author seeks to answer these two questions.</p> / <p>Det lettiska byggbolaget Laval un Partneri Ltd (Laval) utstationerade under hösten 2004 lettiska byggarbetare på ett skolbygge i Vaxholm. Eftersom bolaget vägrade teckna kollektivavtal med Svenska Byggnadsarbetareförbundet (Byggnads) satte Byggnads bygget i blockad. Laval stämde därefter Byggnads i Arbetsdomstolen (AD) och krävde skadestånd eftersom Laval anser att blockaden, liksom Byggnads krav på att Laval skulle teckna kollektivavtal, strider mot EG-rätten. AD har nu begärt ett förhandsavgörande i målet från EG-domstolen. I avvaktan på EG-domstolens avgörande står flera principiellt viktiga frågor i målet obesvarade. Dessa är bl a huruvida Lex Britannia och Sveriges sätt att implementera utstationeringsdirektivet (96/71/EG) är förenliga med EG-rätten. Det är dessa frågor som författaren ämnar besvara i uppsatsen.</p>
45

Utstationering av utländska arbetstagare i Sverige : Är Lex Britannia och Sveriges sätt att implementera utstationeringsdirektivet (96/71/EG) förenliga med EG-rätten?

Sanfridsson, Karin January 2005 (has links)
The Latvian building company Laval un Partneri Ltd (Laval) posted Latvian construction workers at the rebuilding of a school in Vaxholm in autumn 2004. Because the company refused to sign a collective agreement with Svenska Byggnadsarbetareförbundet (Byggnads), which is the Swedish trade union for constructions workers, Byggnads put the construction site under a boycott. Next Laval sued Byggnads for damages in the Swedish Labour Court (AD) because Laval considers the boycott as well as Byggnad´s demand that Laval signs a collective agreement incompatible with EC Law. AD has now demanded a preliminary ruling from the European Court of Justice (ECJ). While waiting for the preliminary ruling from the ECJ, several important questions of principle stand unanswered. Two such questions are whether Lex Britannia and the way in which Sweden har implemented the directive for posted workers (96/71/EC) are compatible with EC Law. In this thesis the author seeks to answer these two questions. / Det lettiska byggbolaget Laval un Partneri Ltd (Laval) utstationerade under hösten 2004 lettiska byggarbetare på ett skolbygge i Vaxholm. Eftersom bolaget vägrade teckna kollektivavtal med Svenska Byggnadsarbetareförbundet (Byggnads) satte Byggnads bygget i blockad. Laval stämde därefter Byggnads i Arbetsdomstolen (AD) och krävde skadestånd eftersom Laval anser att blockaden, liksom Byggnads krav på att Laval skulle teckna kollektivavtal, strider mot EG-rätten. AD har nu begärt ett förhandsavgörande i målet från EG-domstolen. I avvaktan på EG-domstolens avgörande står flera principiellt viktiga frågor i målet obesvarade. Dessa är bl a huruvida Lex Britannia och Sveriges sätt att implementera utstationeringsdirektivet (96/71/EG) är förenliga med EG-rätten. Det är dessa frågor som författaren ämnar besvara i uppsatsen.
46

MODELING HETEROTACHY IN PHYLOGENETICS

Zhou, Yan 04 1900 (has links)
Il a été démontré que l’hétérotachie, variation du taux de substitutions au cours du temps et entre les sites, est un phénomène fréquent au sein de données réelles. Échouer à modéliser l’hétérotachie peut potentiellement causer des artéfacts phylogénétiques. Actuellement, plusieurs modèles traitent l’hétérotachie : le modèle à mélange des longueurs de branche (MLB) ainsi que diverses formes du modèle covarion. Dans ce projet, notre but est de trouver un modèle qui prenne efficacement en compte les signaux hétérotaches présents dans les données, et ainsi améliorer l’inférence phylogénétique. Pour parvenir à nos fins, deux études ont été réalisées. Dans la première, nous comparons le modèle MLB avec le modèle covarion et le modèle homogène grâce aux test AIC et BIC, ainsi que par validation croisée. A partir de nos résultats, nous pouvons conclure que le modèle MLB n’est pas nécessaire pour les sites dont les longueurs de branche diffèrent sur l’ensemble de l’arbre, car, dans les données réelles, le signaux hétérotaches qui interfèrent avec l’inférence phylogénétique sont généralement concentrés dans une zone limitée de l’arbre. Dans la seconde étude, nous relaxons l’hypothèse que le modèle covarion est homogène entre les sites, et développons un modèle à mélanges basé sur un processus de Dirichlet. Afin d’évaluer différents modèles hétérogènes, nous définissons plusieurs tests de non-conformité par échantillonnage postérieur prédictif pour étudier divers aspects de l’évolution moléculaire à partir de cartographies stochastiques. Ces tests montrent que le modèle à mélanges covarion utilisé avec une loi gamma est capable de refléter adéquatement les variations de substitutions tant à l’intérieur d’un site qu’entre les sites. Notre recherche permet de décrire de façon détaillée l’hétérotachie dans des données réelles et donne des pistes à suivre pour de futurs modèles hétérotaches. Les tests de non conformité par échantillonnage postérieur prédictif fournissent des outils de diagnostic pour évaluer les modèles en détails. De plus, nos deux études révèlent la non spécificité des modèles hétérogènes et, en conséquence, la présence d’interactions entre différents modèles hétérogènes. Nos études suggèrent fortement que les données contiennent différents caractères hétérogènes qui devraient être pris en compte simultanément dans les analyses phylogénétiques. / Heterotachy, substitution rate variation across sites and time, has shown to be a frequent phenomenon in the real data. Failure to model heterotachy could potentially cause phylogenetic artefacts. Currently, there are several models to handle heterotachy, the mixture branch length model (MBL) and several variant forms of the covarion model. In this project, our objective is to find a model that efficiently handles heterotachous signals in the data, and thereby improves phylogenetic inference. In order to achieve our goal, two individual studies were conducted. In the first study, we make comparisons among the MBL, covarion and homotachous models using AIC, BIC and cross validation. Based on our results, we conclude that the MBL model, in which sites have different branch lengths along the entire tree, is an over-parameterized model. Real data indicate that the heterotachous signals which interfere with phylogenetic inference are generally limited to a small area of the tree. In the second study, we relax the assumption of the homogeneity of the covarion parameters over sites, and develop a mixture covarion model using a Dirichlet process. In order to evaluate different heterogeneous models, we design several posterior predictive discrepancy tests to study different aspects of molecular evolution using stochastic mappings. The posterior predictive discrepancy tests demonstrate that the covarion mixture +Γ model is able to adequately model the substitution variation within and among sites. Our research permits a detailed view of heterotachy in real datasets and gives directions for future heterotachous models. The posterior predictive discrepancy tests provide diagnostic tools to assess models in detail. Furthermore, both of our studies reveal the non-specificity of heterogeneous models. Our studies strongly suggest that different heterogeneous features in the data should be handled simultaneously.
47

Sustainable Polymer Production: Investigating Synthesis and Copolymerization of Cyclic Ketene Acetals / Hållbar polymerproduktion: Undersökning och syntes samt sampolymerisation av cykliska ketenacetaler

Bourraman, Soufian, Staffas, Stella, Brandt, Adam, Isaksson, Simon January 2023 (has links)
The large amount of non-degradable plastic waste has become a significant environmental concern, leading to an increased need for degradable plastics. Here in, to create degradable polymers, polyesters were produced through radical ring opening polymerization using cyclic ketene acetals. The cyclic ketene acetal monomer 5,6-benzo-2-methylene-1,3-dioxepane has been prepared for the synthesis of homo- and copolymers with methyl methacrylate, α-methylene-γ-valerolactone, α-methylene-γ-butyrolactone, cholesterol methacrylate and limonene acrylate. The polymerization was conducted using radical ring opening polymerization both in bulk and solution polymerization. The structural characteristics of the polymer were determined by different characterization methodologies, including TGA, DSC, SEC, FTIR and 1D 1H-NMR. The results obtained from 1H-NMR analysis showed the composition of the copolymers. TGA analysis revealed the thermal stability of the polymers and their degradation patterns. DSC analysis provided information about the glass transition temperatures (Tg’s) of the polymers. Moreover, the Tg indicated the presence and amounts of comonomers in the copolymers. Overall, the results showed the influence of different comonomers on the properties of the polymers by successfully incorporating the comonomers in the polymer. The thermal properties for polymers containing methyl methacrylate became more thermally stable. The Tg, analyzed with DSC, shifted from the Tg of homopolymers indicating the incorporation of both monomers. The polymers were successfully degraded via hydrolysis in alkaline conditions breaking them down into smaller pieces making them easier to recycle. To conclude, the results all indicate that the incorporation of BMDO and thereby possibly other CKA-monomers into the polymer chains of commonly used plastics could provide valuable tools in the recycling of said plastics.
48

Kollektivavtalsrätten och ideologierna : Ideologies and Swedish Labour Law

Berg, Lisa, von Zedtwitz-Liebenstein, Sangrid January 2011 (has links)
Abstract   The overall aim of this paper is to examine the impact of ideologies and norms on a legal system. Against a background of a description of the hierarchy of norms in Swedish labour law and in European Union law, respectively, the paper aims to specifically demonstrate the problems caused by the different hierarchies of norms when implementing EU directives in Swedish labor law.   The research question examines how the trade unions’ right to industrial action towards an undertaker providing transnational services by posting of workers, is affected by the implementation of the Directive 96/71/EC of the European Parliament and of the Council of 16 December 1996 concerning the posting of workers in the framework of the provision of services. The paper answers the question under what conditions the Swedish trade unions have the right to take industrial action in situations of posting of workers.   Through the study of sources of law and adhering to traditional jurisprudence, this paper investigates the legislation regarding trade unions’ rights to take industrial action in situations of posting of workers.   In addition to the jurisprudential research, a glance at the history of ideologies is provided. The purpose of this is to explain the role of ideologies in the origins and history of Swedish labour law, as well as their role in the current development of law. With the ideological and historical discussion as a background, this paper investigates Swedish law and EU law using a comparative approach. The purpose is to illustrate how differences in ideological bases are determinant of differences in current legislation and legal practice.   The paper studies the development of law since the 1990s with regards to the right to industrial action in situations of posting of workers. The Swedish labour law has been revised since Sweden joined the European Union. The presentation looks particularly at the following cases in the Swedish Labour Court: AD 1989 No. 120 (the Britannia case) and AD 2005 No. 49 (the Vaxholm case). The paper studies the Posting of Workers Directive and presents an analysis of the European Court of Justice Case C-341/05 Laval un Partneri Ltd (the Laval case). To allow for analysis and a broad discussion on the implementation of the Posting of Workers Directive, an account is made of the different government committee instructions, committee of inquiry reports, and governmental legislative proposals of importance for the implementation of the directive into the Foreign Posting of Employees Act, and for the legislative changes prompted by the Laval case (i.e. the lex Laval).   The main conclusion drawn from the study of the legislative development is that the level of legislation of the Swedish labour market will increase due to the tendency of europeanisation. The study also establishes the importance of ideologies, norms and values for the development of a legal system. This paper does not fully answer whether the set of norms on which Swedish labour law is based is about to change, but the trend is that on the whole no such changes have been observed. The existence of lex Laval has not affected the basic set of norms of Swedish labour law.

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