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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.
531

Three Topics in Descriptive Set Theory

Kieftenbeld, Vincent 05 1900 (has links)
This dissertation deals with three topics in descriptive set theory. First, the order topology is a natural topology on ordinals. In Chapter 2, a complete classification of order topologies on ordinals up to Borel isomorphism is given, answering a question of Benedikt Löwe. Second, a map between separable metrizable spaces X and Y preserves complete metrizability if Y is completely metrizable whenever X is; the map is resolvable if the image of every open (closed) set in X is resolvable in Y. In Chapter 3, it is proven that resolvable maps preserve complete metrizability, generalizing results of Sierpiński, Vainštein, and Ostrovsky. Third, an equivalence relation on a Polish space has the Laczkovich-Komjáth property if the following holds: for every sequence of analytic sets such that the limit superior along any infinite set of indices meets uncountably many equivalence classes, there is an infinite subsequence such that the intersection of these sets contains a perfect set of pairwise inequivalent elements. In Chapter 4, it is shown that every coanalytic equivalence relation has the Laczkovich-Komjáth property, extending a theorem of Balcerzak and Głąb.
532

Concentrações plasmaticas e salivares e efeito sobre a microbiota oral de duas formulações de amoxicilina : estudo em voluntarios sadios

Baglie, Sinvaldo 16 February 2005 (has links)
Orientador: Francisco Carlos Groppo, Pedro Luiz Rosalen / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-04T02:16:09Z (GMT). No. of bitstreams: 1 Baglie_Sinvaldo_D.pdf: 818069 bytes, checksum: 1c0d1eb4621ca27afda369d7e188a9a7 (MD5) Previous issue date: 2005 / Resumo: As concentrações de amoxicilina (AMO)em plasma e saliva e seus efeitos na microbiota oral de voluntários sadios foram analisados, em um estudo aberto, de forma aleatória, cruzado com dois períodos. AMO875 mg (Amoxicilina-EMS- medicamento teste e Amoxil@- medicamentoreferência) foi administrada para todos os voluntários com 1 semana de intervalo entre as doses. Amostras de plasma e saliva foram colhidas em um intervalo de até 12h após a administração. As concentrações plasmáticas de AMOforam obtidas por cromatografia líquida e espectrometria de massas com ionização por electrospray (LC-ESI-MS). As concentrações de amoxicilina em saliva foram analisadas por cromatografia líquida de alta eficiência (HPLC).As contagens dos microrganismos totais, anaeróbios e estreptococos foram obtidas em diferentes condições de cultura. ASC foi calculada pelo método de extrapolação dos trapezóides. Cmaxe Tmaxforam compilados dos dados de concentração-tempo. Análise de variância foi realizada usando dados logaritmicamente transformadospara ASCo-inf, ASCO-12h, Cmax e não transformados para Tmax.As médias (:1:dp) para ASCO-12h (jJg.h.mL-1),ASCo-inf (jJg.h.mL-1),Cmax (jJg.mL-1)and Tmax(h), foram respectivamente: 55,42(:1:16,85), 55,42 (:1:16,85), 18,59 (:1:6,3), 2,04(:1:0,75) para o medicamento teste e 51,11 (:1:18,9), 51,29 (:1:19,12), 17,83 (:1:5,86),2,02 (:i:O,87)para o medicamento referência. Intervalos de confiança (90%) para a razão das médias de AMO(testejreferência) para ASCO-12he Cmaxforam: 0,961-1,149 e 0,914 - 1,142, respectivamente. Tanto para as concentrações plasmáticas quanto para as salivares não foram observadas diferenças estatisticamente significantes entre os dois medicamentos (Teste t pareado, p>0.05). As contagens de microrganismos provindos da saliva não mostraram diferenças estatísticas (ANOVAde medidas repetidas, p>0.05) entre as duas formulações durante cada tempo. A partir de 60 min, uma redução estatisticamente significante (ANOVAde medidas repetidas, p<0.05) foi observada para todos os microrganismos. Os dois medicamentos foram considerados bioequivalentes baseado na razão e extensão de absorção e foram eficazes na redução dos microrganismos da microbiota oral avaliados até 12 horas / Abstract: The plasmatic and salivary concentration of amoxicillin(AMO)875mg and its effects on oral microbiota in healthy volunteers were assessed in an open, randomized, two-period crossover designo A single 875 mg oral dose of AMO (Amoxicillin-EMS- test formulation and Amoxil@- reference formulation) was administered to ali volunteers observing 1-week intervaI between doses. Blood and saliva samples were collected from pre-dose to 12 h. The concentrations of AMO, in plasma and saliva, were quantified by LC-ESI-MSand LCmethod, respectively. AUC was calculated by the trapezoidal rule extrapolation method. Cmaxand Tmax were compiled from the plasmatic concentration-time data. Streptococci, anaerobe, and total microorganisms' counts were obtained in different culture conditions. The mean values (:1:SD) for AUCO-12(lh1g.h.mL-1),AUCO-í(nlf1g.h.mL-1),Cmax(l1g.mL-1) and Tmax(h), were respectively: 55.42(:1:16.85), 55.42 (:I:16.85), 18.59 (:I:6.3), 2.04{:I:0.75) concerning the test formulation and 51.11 (:I:18.9), 51.29 (:I:1,9.12), 17.83 (:I:5.86), 2.02 (:1:0.87) concerning the reference formulation. Confidence intervals (90%) of amoxicillinmeans of AUCO-12ahnd Cmaxratios (testjreference) were: 0.961 - 1.149 and 0.914 - 1.142, respectively. No statistically significant differences were observed between the two formulations (t test, p>0.05) regarding AMOplasmatic and saliva concentrations. Saliva microorganisms counts did not show statistical differences (ANOVArepeated measures, p>0.05) between the two groups during each sampling time. Starting at 60 min, a statistically significant decrease (ANOYArepeated measures, p<0.05) was also observed for all microorganisms. Both formulations were bioequivalent based on both the rate and extent of absorption, and were effective in reduce microorganisms until 12 hours / Doutorado / Farmacologia, Anestesiologia e Terapeutica / Doutor em Odontologia
533

Avaliação de equivalência substancial e potencial de alergenicidade de cultivares de soja tolerantes ao herbicida glifosato / Evaluation of substantial equivalence and potential of allergenic reactions of soybean cultivars tolerant to the glyphosate herbicide

Cintia Bezuti Giora 25 June 2009 (has links)
Os parâmetros de avaliação de segurança de alimentos geneticamente modificados fundamentam-se na comparação de equivalência substancial entre as variedades e pela inocuidade de proteínas da planta GM com as proteínas encontradas nas plantas convencionais. O objetivo deste trabalho foi avaliar a segurança alimentar de três cultivares de sojas geneticamente modificadas para tolerarem o herbicida glifosato através da determinação da equivalência substancial e do potencial alergênico das mesmas quando comparadas às suas respectivas parentais isogênicas. Seis amostras de soja foram analisadas, sendo três convencionais parentais e três GM, referentes ao cultivo de 2004-2005, em Goiás. Para a composição química foram realizadas análises em triplicata de proteínas, lipídeos, umidade, minerais e fibra alimentar. Análises complementares para determinação de aminoácidos, ácidos graxos, isoflavonas e ácido fítico também foram realizadas. O potencial de alergenicidade foi avaliado em extratos protéicos brutos de três cultivares convencionais e suas correspondentes GM. Os mesmos extratos protéicos foram fracionados para obter as globulinas 7S e 11S por precipitação e posterior purificação em coluna de bioafinidade Sepharose 4B. A glicoproteína 7S foi obtida a partir da eluição com tampão contendo -D-mannopyranoside. A resistência à proteólise foi realizada a partir de dois fluidos gástricos simulados com pepsina nas proporções 2,5:100 e 13:1 de enzima/substrato. As amostras foram submetidas à eletroforese dissociante para se estimar a resistência à ação da pepsina em função da concentração da enzima e do tempo de incubação. Extratos brutos protéicos e frações hidrolisadas foram testados contra soros de pacientes comprovadamente alérgicos e não alérgicos à soja nas concentrações de 1/20 em ensaios imunoquímicos do tipo ELISA e 1/10 em ensaios do tipo Western blotting. Os resultados da composição básica de nutrientes mostraram dispersões normais esperadas entre as amostras de mesma origem, com tendências de níveis superiores de proteínas de 9 a 16% nas amostras GM. As análises de fibras insolúveis e isoflavonas revelaram valores de decréscimo das amostras GMs em relação aos teores das variedades convencionais, contrastando com o acréscimo de valores de ácido fítico nas mesmas cultivares. Quanto à proteólise, foi possível observar estabilidade de bandas protéicas com pesos moleculares em torno de 50 e 18 KDa nos extratos brutos, 10 KDa nos extratos de 11S e 50 KDa nos extratos de 7S, em geral similares entre as parentais isogênicas e GMs. Os testes de reatividade dos soros de pacientes alérgicos e não alérgicos em extratos brutos protéicos das cultivares GM demonstraram reatividade similar quando comparados às suas respectivas parentais isogênicas. Com a observação dos resultados pode-se concluir que as diferenças significativas apresentadas pelas amostras GM não as tornam inseguras para o consumo humano e animal. Da mesma forma que não foram observadas alterações na alergenicidade das amostras GM em relação às amostras parentais isogênicas por apresentarem perfis semelhantes de proteólise frente à pepsina e aos testes imunológicos contra soros de pacientes alérgicos. / The parameters of security evaluation of genetically modified foods are based on the substantial equivalence among varieties and the innocuity of GM vegetal proteins compared with conventional vegetal proteins. The aim of this work was to evaluate the food safety of three genetically modified soybean cultivars to tolerate glyphosate herbicide through substantial equivalence determination and allergenic potential when compared to their respective isogenic parental. Six samples analyzed were three parental soybean (conventional) and the others GM, regarding to the crop of 2004-2005, grown in Goiás state. The chemical composition was performed in triplicate and the content of moisture, minerals, proteins, lipids and fiber were determined. Additional compounds like aminoacids, fatty acids, isoflavons and phytates were analyzed. The potential of allergenic reactions was evaluated in crude protein extracts of three conventional and their corresponding GM cultivars. The same protein extracts were fractionated to obtain 7S and 11S globulins by precipitation and posterior purification on Sepharose 4B bioaffinity column. The 7S glycoprotein was obtained by elution with -D-mannopyranoside buffer. The resistance to proteolysis was performed by two simulated gastric fluids with pepsin at the proportions 2,5:100 and 13:1 enzyme/substrate. The samples were run by SDS electrophoresis to estimate the resistance to pepsin action according to enzyme concentration and incubation time. Crude protein extracts and hydrolyzed fractions were tested against serum of allergic and non-allergic patients through ELISA immunochemistry essays at concentrations of 1/20 and Western blotting, 1/10. The results of chemical composition of nutrients showed an expected normal dispersion among samples from the same origin, with tendencies for superior levels of proteins from 9 to 16% by GM samples. The analyses of insoluble fibers and isoflavons revealed decreased values at GM samples regarding to the contents on conventional varieties, contrasting with the increase of the phytic acid values in the same cultivars. After the proteolysis, some protein bands remained apparently stable, that correspond to molecular weights around 50 and 18 KDa for crude extracts, 10 KDa for 11S extracts and 50 KDa for 7S extracts. The undigested proteins are similar in both set of samples, the parental isogenic and GM soybeans. Immuno-reactivity of proteins from crude extracts with serum from allergic and non allergic patients were also similar for isogenic and GM cultivars. These results allow us to state that the significant differences observed in the composition of GM samples will neither affect the nutrient levels nor the safety of their consumption as food or feed. As well as there were no observed changes at the potential allergenicity of GM samples regarding to parental isogenic samples by exhibit similar proteolysis profile related to pepsin and immunological essays against allergic patient serums.
534

Kateřina Šichová: Mit Händen und Füßen reden. Verbale Phraseme im deutschtschechischen Vergleich: Buchbesprechung

Tyczka, Agnieszka 20 July 2020 (has links)
In den letzten vier Jahrzehnten hat sich auf dem Gebiet der vergleichenden Phraseologieforschung eine kontinuierliche Entwicklung vollzogen, die sich auf den Forschungsbedarf der Übersetzungswissenschaft, der Lexikographie und der Fremdsprachendidaktik gründet. Vor allem seit den 1990er Jahren entstanden viele auf theoretischer und auch praktischer Ebene fundierte germanistische Studien. Zu nennen sind zum Beispiel Barbara Wotjaks „Verbale Phraseolexeme in System und Text“ (1992), Csaba Földes’ „Deutsche Phraseologie kontrastiv. Intra- und interlinguale Zugänge“ (1996) oder der von Harmut Lenk und Stephan Stein herausgegebene Band „Phraseologismen in Textsorten“ (2011). Zum Tschechischen liegen wichtige Untersuchungen vor wie die von Franz Schindler, „Das Sprichwort im heutigen Tschechischen. Empirische Untersuchung und semantische Beschreibung“ (1993) oder Helgunde Henschels „Die Phraseologie der tschechischen Sprache“ (1993).
535

BRISTANDE SAMSYN OCH NYANLÄNDA OCH FLERSPRÅKIGA ELEVER : Problemrepresentationer och diskursiva tystnader i svensk skola

Akyol, Nadja, Hagi Ali, Filsan January 2021 (has links)
The purpose of the thesis is to study how Umeå municipality explicitly approaches what constitutes quality and problems in school activities and how it can be understood in relation to segregation andequality. Using Bacchis ``What's the problem represented to be´´-approach we seek to analyse what problems are presented, how the municipality aims to handle the problem and what the discursive effects of these representations are. The analysis is based on the Municipality's quality report 2019/20.The main problem discussed lies with school staff who partly do not understand their assignment and partly prioritize certain parts of the curriculum over others. Non-ethnic Swedish students (“recently arrived”, “multi lingual students” and “students born abroad”) are described as a monolithic and especially problematic category due to parents’ cultural views and lacking language skills. In both these representations the wider social context of e g segregation, is disregarded, and power of the municipality to deal with the described problems are minimized.
536

Vote électronique : définitions et techniques d'analyse / Electronic Voting : Definitions and Analysis Techniques

Lallemand, Joseph 08 November 2019 (has links)
Cette thèse porte sur l'étude de différents aspects de la sécurité des protocoles de vote électronique à distance. Ces protocoles décrivent comment organiser des élections par Internet de manière sécurisée. Ils ont notamment pour but d'apporter des garanties de secret du vote, et de vérifiabilité - ie, il doit être possible de s'assurer que les votes sont correctement comptabilisés. Nos contributions portent sur deux aspects principaux. Premièrement, nous proposons une nouvelle technique d'analyse automatique de propriétés d'équivalence, dans le modèle symbolique. De nombreuses propriétés en lien avec la vie privée s'expriment comme des propriétés d'équivalence, telles que le secret du vote en particulier, mais aussi l'anonymat ou la non-traçabilité. Notre approche repose sur le typage: nous mettons au point un système de typage qui permet d'analyser deux protocoles pour prouver leur équivalence. Nous montrons que notre système de typage est correct, c'est-à-dire qu'il implique effectivement l'équivalence de traces, à la fois pour des nombres bornés et non bornés de sessions. Nous comparons l'implémentation d'un prototype de notre système avec les autres outils existants pour l'équivalence symbolique, sur divers protocoles de la littérature. Cette étude de cas montre que notre procédure est bien plus efficace que la plupart des autres outils - au prix d'une perte de précision (notre outil peut parfois échouer à prouver certaines équivalences). Notre seconde contribution est une étude des définitions du secret du vote et de la vérifiabilité - ou, plus précisément, la vérifiabilité individuelle, une propriété qui requiert que chaque votant soit en mesure de vérifier que son propre vote a bien été pris en compte. Nous prouvons, aussi bien dans les modèles symboliques que calculatoire, que le secret du vote implique la vérifiabilité individuelle, alors même que l'intuition et des résultats voisins déjà établis semblaient indiquer que ces deux propriétés s'opposent. Notre étude met également en évidence une limitation des définitions existantes du secret du vote par jeux cryptographiques : elles supposent une urne honnête, et par conséquent expriment des garanties significativement plus faibles que celles que les protocoles visent à assurer. Nous proposons donc une nouvelle définition (par jeu) du secret du vote, contre une urne malhonnête. Nous relions notre définition à une notion de secret du vote par simulation, pour montrer qu'elle apporte des garanties fortes. Enfin, nous menons une étude de cas sur plusieurs systèmes de vote existants. / In this thesis we study several aspects of the security of remote electronic voting protocols. Such protocols describe how to securely organise elections over the Internet. They notably aim to guarantee vote privacy - ie, votes must remain secret -and verifiability - it must be possible to check that votes are correctly counted. Our contributions are on two aspects. First, we propose a new approach to automatically prove equivalence properties in the symbolic model. Many privacy properties can be expressed as equivalence properties, such as in particular vote privacy, but also anonymity or unlinkability. Our approach relies on typing: we design a type system that can typecheck two protocols to prove their equivalence. We show that our type system %, together with some additional conditions on the messages exchanged by the protocols, soundly implies trace equivalence, both for bounded and unbounded numbers of sessions. We compare a prototype implementation of our typechecker with other existing tools for symbolic equivalence, on a variety of protocols from the literature. This case study shows that our procedure is much more efficient than most other tools - at the price of losing precision (our tool may fail to prove some equivalences). Our second contribution is a study of the definitions of privacy and verifiability - more precisely, individual verifiability, a property that requires each voter to be able to check that their own vote is counted. We prove that, both in symbolic and computational models, privacy implies individual verifiability, contrary to intuition and related previous results that seem to indicate that these two properties are opposed. Our study also highlights a limitation of existing game-based definitions of privacy: they assume the ballot box is trusted, which makes for significantly weaker guarantees than what protocols aim for. Hence we propose a new game-based definition for vote privacy against a dishonest ballot box. We relate our definition to a simulation-based notion of privacy, to show that it provides meaningful guarantees, and conduct a case study on several voting schemes.
537

Weak-Equivalence Principle Violation and Mass Change of Charged Matter Due to Vacuum Polarization

Tajmar, Martin January 2016 (has links)
Vacuum polarization by electric fields is a well established fact. Assuming that anti-matter has negative gravitational properties, the fluctating electric dipoles from the quantum vacuum may also have gravitational dipolar properties. A model is developed that describes how electric fields could gravitationally polarize the vacuum causing gravitational screening or anti-screening effects. This leads to a violation of the Weak Equivalence Principle or a general mass change most notabily for elementary particles, such as the electron or positron, below but close to measured boundaries. Also a gravitational vacuum torque is predicted to act on a charged capacitor perpendicular to a gravitational field. The predictions could be verified by future laboratory experiments that could contribute on our understanding of the gravitational properties of anti-matter.
538

Lokální-globální princip pro kvadratické formy / Local-global principle for quadratic forms

Surý, Pavel January 2020 (has links)
Local-global principle for quadratic forms This work will be focused on the problems of representation and equivalence for quadratic forms. We will prove the fundamental Hasse-Minkowski theorem, which describes the rational representation and equivalence using properties of the form over the completions of Q: the real and p-adic numbers. We will refer to this procedure as local-global principle. Furthermore, we shall describe the methods for computing the p-adic invariants, and show their relation to the representation problem. Finally, we show how the local-global partially extends to integral forms, in particular to indefinite ones of dimension at least 4. 1
539

Třídy modulů motivované algebraickou geometrií / Classes of modules arising in algebraic geometry

Slávik, Alexander January 2020 (has links)
This thesis summarises the author's results in representation theory of rings and schemes, obtained with several collaborators. First, we show that for a quasicompact semiseparated scheme X, the derived category of very flat quasicoherent sheaves is equivalent to the derived category of flat quasicoherent sheaves, and if X is affine, this is further equivalent to the homotopy category of projectives. Next, we prove that if R is a commutative Noetherian ring, then every countably generated flat module is quite flat, i.e., a direct summand of a transfinite extension of localizations of R in countable multiplicative subsets. Further, we investigate the relations between the geometric and categorical purity in categories of sheaves; we give a characterization of indecomposable geometric pure-injectives in both the quasicoherent and non-quasicoherent case. In partic- ular, we describe the Ziegler spectrum and its geometric part for the category of quasicoherent sheaves on the projective line over a field. The final result is the equivalence of the following statements for a quasicompact quasiseparated scheme X: (1) the category QCoh(X) of all quasicoherent sheaves on X has a flat generator; (2) for every injective object E of QCoh(X), the internal Hom functor into E is exact; (3) for some injective...
540

A Class of Stochastic Petri Nets with Step Semantics and Related Equivalence Notions

Buchholz, Peter, Tarasyuk, Igor V. 15 January 2013 (has links)
This paper presents a class of Stochastic Petri Nets with concurrent transition firings. It is assumed that transitions occur in steps and that for every step each enabled transition decides probabilistically whether it wants to participate in the step or not. Among the transitions which what to participate in a step, a maximal number is chosen to perform the firing step. The observable behavior is defined and equivalence relations are introduced. The equivalence relations extend the well-known trace and bisimulation equivalences for systems with step semantics to Stochastik Petri Nets with concurrent transition firing. It is shown that the equivalence notions form a lattice of interrelations.

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