The extensive and sometimes incorrect and noncompliant use of various types of antimicrobial agents has accelerated the development of antimicrobial resistance (AMR). In fact, AMR has become one of the greatest global threat to human health in this era. The broad-spectrum antibiotics aminoglycosides (AGs) display excellent potency against most Gram-negative bacteria, mycobacteria, and some Gram-positive bacteria, such as Staphylococcus aureus. The AG antibiotics amikacin, gentamicin, kanamycin, and tobramycin are still commonly prescribed in the U.S.A. for the treatment of serious infections. Unfortunately, bacteria evolve to acquire resistance to AGs via four different mechanisms: i) changing in membrane permeability to resist drugs from entering, ii) upregulating efflux pumps for active removal of intracellular AGs, iii) modifying the antimicrobial target(s) to prevent drugs binding to their targets, and iv) acquiring resistance enzymes to chemically inactivate the compounds. Amongst all, the acquisition of resistance enzymes, AG-modifying enzymes (AMEs), is the most common resistance mechanism identified. Depending on the chemistry each enzyme catalyzes, AMEs can be further divided into AG N-acetyltransferases (AACs), AG O-phosphotransferases (APHs), and AG O-nucleotidyltransferases. To overcome AME-related resistance, we need to better understand these resistance enzymes and further seek ways to either escape or inhibit their actions. In this dissertation, I summarized my efforts to characterize the AAC(6') domain and its mutant enzymes from a bifunctional AME, AAC(6')-Ie/APH(2")-Ia as well as another common AME, APH(3')-IIa. I also explained my attempt to inhibit the action of various AAC enzymes using metal salts. In an effort to explore the current resistance epidemic, I evaluated the resistance against carbapenem and AG antibiotics and the correlation between the resistance profiles and the AME genes in a collection of 122 Pseudomonas aeruginosa clinical isolates obtained from the University of Kentucky Hospital System. Besides tackling the resistance mechanisms in bacteria, I have also attempted to explore a new antifungal option by repurposing an existing antipsychotic drug, bromperidol, and a panel of its derivatives into a combination therapy with the azole antifungals against a variety of pathogenic yeasts and filamentous fungi.

The purpose of the study was to question rural general education teachers’ perceptions and attitudes on the inclusion of students with significant disabilities. The investigator surveyed rural general education teachers on their perceptions of what should be occurring in terms of inclusion and on what they saw as occurring in terms of inclusion of students with significant disabilities. The results yielded mixed perceptions and were generally positive in terms of the inclusion occurring within that school district.

Memory formation in Drosophila melanogaster is composed of two pathways that are genetically distinct, and functionally independent of each other. These are short-term and long-term memory. Short-term memory is a transient phenomenon, located in the cytoplasm of the neuronal cells, which requires no alteration of gene expression. The formation of long-term memory requires a change in gene expression, therefore chromatin-modifying complexes may play an integral part. The mushroom-bodies of Drosophila are a distinct bilateral brain structure and are essential for the formation and recollection of long-term memory. Therefore, an alteration in gene expression within the mushroom bodies is essential to the formation of long-term memory. Disruption of a gene within the mushroom-bodies that resulted in an alteration in the formation of long-term memory would indicate that the gene is involved in long-term memory. In order to investigate the role of the two chromatin-modifying proteins, HDACX and pr-Set7, whose role in memory function is unknown, RNA interference was used to knockdown expression of their respective mRNA. Published GAL4 lines were used to drive down expression in the mushroom bodies. The efficacy of the knockdown on levels of mRNA was measured by quantitative RT-PCR. The effect of these knockdowns on the formation of long-term memory was assayed using conditioned courtship. Additionally, the actual spatial and temporal expression of the GAL4 drivers was investigated using fluorescent proteins, and analysed using fluorescent microscopy. Both pr-set7 and HDACX appear to play a role in long-term memory function. The RNAi-induced knockdown of the individual mRNAs caused impairment in long-term memory formation, although the exact mode of action is still to be elucidated. The levels of mRNA from these knockdowns were reduced within the head, although not to the extent expected. The fluorescent microscopy analysis indicated that the expression of mushroom-body specific GAL4 drivers was more widespread than previously reported.

I have examined three different topological forms of a material modifier. The modifier is silicone and the three topological forms are cyclic, linear tethers and networked siloxane bonds in the form of a nanoparticulate. Often silicones, or siloxanes, are added to a material because of its unique properties that are related to its inorganic or inorganic-organic hybrid character. This dissertation addresses either the synthesis of silicones for material modification or the effect of the adding silicones to a variety of substrates and polymeric systems. Chapters 2 and 3 present research focused on the first topological form, cyclic PDMS. The synthesis of cyclic polymers is very important to the synthesis and subsequent characterization of cyclic containing multi-component materials. Cyclic PDMS is formed via ring-chain depolymerization and bimolecular coupling and the unique issues associated with the formation, purification and analysis of cyclic polymer topologies. The goal of the work described in these chapters was to find a straightforward high-yield route to form large cycles of PDMS in a relatively high purity. Chapter 4 focuses on the modification of the next topological form, linear polymers as tethers for surface modification and presents a novel concept for surface-modifying compounds; the incorporation of an ionic-reactive functionality into PDMS is presented. The idea being its ionic character will increase affinity for the surface, surface coverage and levelness, while the subsequent reactive fixation will permanently modify the surface to improve retention and fastness. The use of such chemistry has not been applied for surface modification protocols. Chapters 5, 6 and 7 discuss the characterization of systems with the third topological form incorporated. They include differences in the viscoelastic behavior of PVAc/silica nanocomposites and the neat PVAc matrix, relating those differences to polymer dynamics and structure as determined by several solid-state NMR experiments. The latter two chapters pertain to PVAc/silica nanocomposites with PDMS surface treatments. Specifically, evaluating how polymer dynamics and structure changes particularly at the interfaceinterphase with various PDMS surface treatments having different topologies at the surface.

Recent advances in high throughput technology have opened the door to systematic studies of epigenetic mechanisms. One of the key components in the regulation of the cell cycle and differentiation is the retinoblastoma protein (pRB), a component of the RB/E2F tumor suppressor pathway that is frequently deregulated in cancer. The RBP2/KDM5A histone demethylase was shown to interact with pRB and regulate pRB function during differentiation. However, how precisely differentiation is coupled with halted cell cycle progression and whether an epigenetic mechanism is involved remain unknown. In the present study, I analyzed gene expression levels of human histone methyltransferases (HMT) and demethylases (HDM), as well as their targets in human cancers; and focused on RB/KDM5A connection in control of cell cycle and differentiation. In particular, I used Drosophila as a model to describe a novel mechanism where the RB/E2F pathway interacts with the Hippo tumor suppressor pathway to synergistically control cell cycle exit upon differentiation. Studying the role of miR-11, I found that the inhibition of dE2F1-induced cell death is its highly specialized function. Furthermore, I studied the induction of differentiation and apoptosis as the consequences of KDM5A deletion in cells derived from Rb knockout mice. I concluded that during differentiation, KDM5A plays a critical role at the enhancers of cell type-specific genes and at the promoters of E2F targets; in cooperation with other repressor complexes, it silences cell cycle genes. I found that KDM5A binds to transcription start sites of the majority of genes with H3K4 methylation. These are highly expressed genes, involved in certain biological processes, and occupied by KDM5A in an isoform-specific manner. KDM5A plays a unique and non-redundant role in histone demethylation and its promoter binding pattern highly overlaps with the opposing enzyme, MLL1. Finally, I found that HMT and HDM enzymes exhibit a distinct co-expression pattern in different cancer types, and this determines the level of expression of their target genes. / Los avances recientes en las tecnologías de alto flujo han abierto el camino a los estudios sistemáticos de los mecanismos epigenéticos. La proteína retinoblastoma (pRB), uno de los elementos de la ruta de supresión de tumores RB/E2F que se encuentra desregulado con frecuencia en el cáncer, es uno de los componentes esenciales de la regulación del ciclo celular y la diferenciación. Sin embargo, aún no se conoce de qué manera precisa la diferenciación se acopla a la detención del avance del ciclo celular y si hay algún mecanismo epigenético vinculado a este proceso. En este estudio, he analizado los niveles de expresión de histona metiltransferasas (HMT) y desmetilasas humanas (HDM), así como sus dianas en cánceres humanos, y me he centrado en la conexión de RB/KDM5A en el control del ciclo celular y la diferenciación. Específicamente, utilicé Drosophila como modelo para describir un mecanismo nuevo mediante el cual RB/E2F interactúa con la ruta Hippo de supresión de tumores para controlar de manera sinérgica la detención del ciclo celular relacionada con la diferenciación. Mediante la investigación del papel de miR-11, determiné que su función altamente especializada es la inhibición de la muerte celular inducida por dE2F1. Además, estudié la inducción de la diferenciación y la apoptosis como consecuencia de la pérdida de KDMA5 en células obtenidas a partir de ratones sin Rb. Extraje como conclusión que, durante la diferenciación, KDMA5 desempeña un papel esencial sobre los estimuladores de los genes específicos de los tipos celulares, así como en los promotores de las dianas de E2F; en cooperación con otros complejos represores silencia a los genes del ciclo celular. Investigué el mecanismo de reclutamiento de KDM5A y encontré que se une al sitio de inicio de la transcripción de la mayoría de los genes que poseen metilación en H3K4. Estos genes tienen elevados niveles de expresión, están involucrados en determinados procesos biológicos y están ocupados por diferentes isoformas de KDM5A. KDM5A desempeña un papel único y no redundante en la desmetilación de las histonas y que en gran medida se solapa con la enzima con la función opuesta, MLL1. Para terminar, encontré que las enzimas HMT y HDM muestran patrones de co-expresión distintos en diferentes tipos de cáncer, y que este hecho determina los niveles de expresión de sus genes diana.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-11-11T17:46:50Z No. of bitstreams: 0 / Made available in DSpace on 2016-11-11T17:46:50Z (GMT). No. of bitstreams: 0 / A movimentação dentária induzida é um processo biológico complexo mediado por estímulos mecânicos, levando a um subsequente processo de remodelação óssea, podendo haver reabsorção indesejada da raiz dentária provocada pelo excesso de força. Uma vez que a movimentação ortodôntica se baseia em um processo inflamatório localizado, o propósito deste estudo foi avaliar os efeitos do laser de baixa potência no processo de remodelação óssea e reabsorção radicular, buscando correlacionar as mudanças metabólicas observadas a nível celular ocorridas nos dias iniciais da movimentação dentária às alterações teciduais observadas microscopicamente e à arquitetura e morfologia do trabeculado e cortical ósseo. Primeiros molares de sessenta e oito ratos machos Wistar foram submetidos à movimentação induzida, divididos em 3 grupos: controle negativo (nenhuma movimentação), não irradiado (movimentação sem irradiação) e laser (movimentação e irradiação com laser de baixa potência de comprimento de onda de 810 nm, potência de 100 mW, área de 0,02cm2 e energia de 1,5 J/ponto) e eutanasiados nos dias 3, 6, 9, 14 e 21. Mensurações da movimentação dentária e análises histomorfométricas foram realizadas em todos os dias estudados. Análise imunoistoquímica dos marcadores RANKL, OPG e TRAP e avaliações por microscopia eletrônica de varredura (MEV) foram feitas nos dias 3, 6 e 9 e o ensaio Western Blotting para proteínas RANKL e SOFAT e imagens de microtomografia computadorizada (MicroCT) nos dias 14 e 21. Os resultados deste estudo mostraram que a movimentação dentária foi significantemente maior no grupo Laser (aumento em média de 40%) em todos os dias avaliados. O lado de compressão mostrou maior expressão de RANKL e osteoclastos TRAP-positivos nos dias 3, 6 e 9 (p<0,05), promovendo significativa redução na área de osso alveolar presente no lado de compressão nos dias 6, 9 e 14 (p<0,05), e alterações microestruturais, como menor fração de volume ósseo/volume total, menor densidade óssea mineral aos 14 dias. A irradiação com laser também aumentou a expressão de RANKL e a citocina SOFAT no dia 14. No lado de tensão, houve maior expressão de OPG especialmente aos 9 dias (p<0,001) e significativo aumento na área de osso alveolar presente nos dias 14 (p<0,01) e 21 (p<0,05) histomorfometricamente e maior densidade óssea mineral e espessura das trabéculas aos 21 dias (p<0,01). Com relação às áreas de hialinização presentes, os resultados mostraram áreas significantemente reduzidas nos dias 3, 6 e 9 nos grupos irradiados, o que explica o menor número de odontoclastos na superfície radicular nestes dias e a redução significante das áreas de reabsorção radicular observadas nas lâminas histológicas nos dias 9, 14 e 21 e nas imagens de MEV nos dias 3 e 9. Os grupos irradiados também mostraram menor volume das lacunas de reabsorção radicular medidas no MicroCT nos dias 14 e 21, especialmente nos lados de compressão. O estudo concluiu que o laser de baixa potência influenciou a remodelação óssea, aumentou a atividade dos osteoclastos no lado da compressão, e estimulou a formação óssea no de tensão, acelerando significativamente o movimento dentário e potencialmente reduzindo as áreas de necrose no ligamento periodontal e, consequentemente, a reabsorção radicular. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-03-22T12:41:12Z No. of bitstreams: 1 robledoestevessantospires.pdf: 1489508 bytes, checksum: 70622a2c796a7c60cf73b540110f1a2f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T02:20:57Z (GMT) No. of bitstreams: 1 robledoestevessantospires.pdf: 1489508 bytes, checksum: 70622a2c796a7c60cf73b540110f1a2f (MD5) / Made available in DSpace on 2016-04-24T02:20:57Z (GMT). No. of bitstreams: 1 robledoestevessantospires.pdf: 1489508 bytes, checksum: 70622a2c796a7c60cf73b540110f1a2f (MD5) Previous issue date: 2013-03-25 / A superlativação de conceitos por meio de projeções figurativas é um fenômeno muito comum à Língua Portuguesa, observado tanto na modalidade escrita quanto oral, e promove a emergência de padrões construcionais com sofisticados mecanismos de estruturação conceptual e formal. O presente estudo identifica, descreve e analisa um desses padrões: a Construção Hiperbólica por Símile – CHS, com especial destaque para as instâncias desta construção instituídas a partir do articulador sintático que nem, como ilustra o elenco de types a seguir: (1) A pobreza é que nem um câncer; (2) Passou por mim que nem um rabo de vento e (3) Inocência enrubesceu que nem uma romã. O aporte teórico central deste estudo advém de dois dos mais relevantes modelos da Linguística Cognitiva, quais sejam, a Gramática das Construções como um Modelo Baseado no Uso (GOLDBERG, 1995, 2006; LAKOFF, 1987; SALOMÃO, 2002-2007, 2009; MIRANDA, 2008-2010; BOAS, 2010) e a Semântica de Frames (FILLMORE, 1968, 1977, 1982), cujas teses apontam para a relevância do uso linguístico e da experiência (de todas as ordens) na arquitetura cognitiva do léxico e da gramática. Nesse enquadre, opta-se por procedimentos metodológicos baseados em corpora e em padrões de frequência de ocorrência e de tipos (GOLDBERG, 2006; BYBEE, 2007; CROFT & CRUSE, 2004). Os resultados certificam o valor semântico-pragmático específico dessas expressões hiperbólicas do Português, assegurando-lhes o estatuto de instâncias de um padrão construcional (a CHS) integrado por três subpadrões. Trata-se de uma construção vinculada à Construção Genérica de Modificação de Grau e cujo constructo ( FILLMORE, GOLDMAN & RHODES, 2010) se desenha pela presença de dois Elementos da Construção (EC): um EC Escopo ou núcleo graduável e um sintagma complexo (EC Qualificador_de_grau) resultante da ampliação de valência do EC Escopo. Evocando o frame Posição_máxima_em_uma_escala, a CHS tem seu Valor_hiperbólico assegurado através da comparação por Símile. Em termos de sua função discursiva, esta construção evocada por que nem, marcadamente informal, seja em modalidade oral ou escrita, demarca o domínio da autoexpressão, da subjetividade nas molduras interativas. / The construction of superlative concepts through figurative projections is a very common phenomenon to Portuguese Language, observed both in written and oral speech, and promotes the emergence of constructional patterns with sophisticated mechanisms for structuring conceptual and formal a language pattern. This study identifies, describes and analyzes one of these patterns: the Hyperbolic Construction by Simile – CHS, with special emphasis on its instances instituted by the syntactic articulator que nem, as illustrates the following types: (1) A pobreza é que nem um câncer; (2) Passou por mim que nem um rabo de vento e (3) Inocência enrubesceu que nem uma romã. The central theoretical assumptions comes from two of the most relevant models developed inside Cognitive Linguistics, namely the Construction Grammar as Used-based Model (GOLDBERG, 1995, 2006, LAKOFF, 1987; SOLOMÃO, 2002-2007, 2009; MIRANDA, 2008-2010; BOAS, 2010) and Frame Semantics (FILLMORE, 1968, 1977, 1982), whose thesis point to the importance of the language use and the experience (of all orders) in the cognitive architecture of the lexicon and grammar. In this framework, it is chosen a corpus-based methodological procedure, with the examination of token and type frequencies (GOLDBERG, 2006; BYBEE, 2007; CROFT & CRUSE, 2004). The results certify the specific semantic-pragmatic value of these hyperbolic expressions of Portuguese, assuring them the status of instances of a constructional pattern (the CHS) integrated for three subpatterns. The construction is linked to the Degree Modifying Generic Construction of which construct (FILLMORE, LEE-GOLDMAN & RHODES, 2010) is drawn by the presence of two construction elements (CE): a CE SCOPE or a gradable core and a complex phrase (CE DEGREE_MODIFIER) resultant from the expansion of the CE SCOPE valence. Evoking the frame Position_on_a_scale, CHS has its Hyperbolic_value ensured by the comparison by Simile. In terms of its discursive function, this construction evoked by que nem, markedly informal, whether in oral or written form, demarcates the area of self expression and subjectivity in interactive frames.

Cluster analysis characterizes data that are similar enough and useful into meaningful groups (clusters).For example, cluster analysis can be applicable to find group of genes and proteins that are similar, to retrieve information from World Wide Web, and to identify locations that are prone to earthquakes. So the study of clustering has become very important in several fields, which includes psychology and other social sciences, biology, statistics, pattern recognition, information retrieval, machine learning and data mining [1] [2].   Cluster analysis is the one of the widely used technique in the area of data mining. According to complexity and amount of data in a system, we can use variety of cluster analysis algorithms. K-means clustering is one of the most popular and widely used among the ten algorithms in data mining [3]. Like other clustering algorithms, it is not the silver bullet. K-means clustering requires pre analysis and knowledge before the number of clusters and their centroids are determined. Recent studies show a new approach for K-means clustering which does not require any pre knowledge for determining the number of clusters [4].   In this thesis, we propose a new clustering procedure to solve the central problem of identifying the number of clusters (k) by imitating the desired number of clusters with proper properties. The proposed algorithm is validated by investigating different characteristics of the analyzed data with modified theory, analyze parameters efficiency and their relationships. The parameters in this theory include the selection of embryo-size (m), significance level (α), distributions (d), and training set (n), in the identification of clusters (k).

L’objectif de cette thèse est d’étudier l’influence de la température sur la thixotropie des bétons autoplaçants (BAP). L’intérêt de ce travail s’inscrit dans la perspective d’optimiser les formulations des BAP dans une large gamme de température. Un plan factoriel composite centré a été adopté dans le but de minimiser le nombre d’essais tout en étudiant les effets des facteurs (température et dosage en agent de viscosité (AV)) et leurs interactions sur les propriétés rhéologiques des BAP.La première phase de l’étude consistait à quantifier la thixotropie du béton juste après le malaxage et durant la période dormante en fonction du dosage en AV à des températures comprises entre 11.3 et 30.7°C selon le protocole proposé par Wallevik sur le rhéomètre BML4. Les résultats ont montré que l’indice de thixotropie présente un minimum respectivement pour un dosage en AV de 0.28 % (par rapport à la masse d’eau) et une température de 24°C. Cependant, ce protocole ne permet pas d’étudier la déstructuration des BAP, facteur recherché par exemple dans les coulages multicouches. Nous avons donc été amenés à retenir un protocole utilisé dans les gels et appelé protocole Dolz. L’application de ce dernier aux pâtes de ciment et aux BAP a permis de mettre en évidence une nouvelle grandeur, le potentiel de déstructuration K. Les valeurs du potentiel K montrent qu’au delà d’un certain dosage en AV et d’une certaine température, apparaissent des phénomènes d’encombrement qui réduisent le potentiel K. Ainsi, le potentiel K apporte des informations complémentaires pour l’aide à la sélection de dosages adéquats du couple superplastifiant – agent de viscosité en fonction de la température de coulage. / The aim of this thesis was to study the influence of the temperature on the thixotropy of self-consolidating concrete (SCC). The research significance comes within the perspective to optimize the design of SCC in a wide range temperature. A factorial composite experimental plan was carried out in order to minimize the total number of tests while studying the effects of factors (temperature and dosage of viscosity modifying admixture (VMA)) and their interactions on the rheological properties of SCC. The first phase of the study was to quantify the thixotropy of concrete proportioned with various dosage of VMA at different temperatures ranging from 11.3 to 30.7°C just after mixing and at different time during the dormant period using the protocol proposed by Wallevik in BML4 rheometer. The results indicated that the values of thixotropy index present a minimum respectively with a VMA dosage of 0.28 % (by mass of water) and a temperature of 24°C.On the other hand, this protocol does not allow studying the destructuration of SCC, useful factor needed for example in the multi-layer casting. We therefore had to retain a protocol used in gels and called Dolz protocol. The application of this last to cement pastes and SCC has revealed a new grandeur, the potential of destructuration K. The values of K show that beyond a certain dosage in VMA and a certain temperature, the congestion phenomena appear that reduce the potential K. In this case, the potential of destructuration provides complementary information to assist in the selection of appropriate dosages of couple superlasticizer-VMA whatever the casting temperature may be.

Currently, increasing reinforced concrete structures and concrete structures that require repair in the form of remediation. The master’s thesis deals with the development of repair mortars with resistance to high temperatures, which would allow the re-profiling of the fire damaged parts of the structures and restore its function. Development of repair mortars is based on a literature review of articles dealing with research materials resistant to high temperatures.