Magíster en Ciencias, Mención Física / La fabricación y posicionamiento de nanopartículas de tamaño y composición ajustable resulta interesante debido a las propiedades que surgen producto del confinamiento en bajas dimensiones. Para acceder a ellas es necesario reemplazar los dispositivos electrónicos macroscópicos típicos por equivalentes nanométricos. En este campo, uno de los mayores retos es elaborar un esquema de medición que permita estudiar el transporte de cargas a través de una nanopartícula individual. Con tal de contactar las nanopartículas a los electrodos en este nuevo esquema, es necesario conocer tanto las propiedades de ambos como sus interacciones. Dado el tamaño reducido de las nanopartículas, resulta fundamental el poder fabricar electrodos nano-espaciados. En esta tesis se realizaron caracterizaciones eléctricas de dos tipos de nanopartículas: análogas al azul Prusiano (PBA por su sigla en ingles) y a base de hierro. Dichas nanopartículas fueron depositadas sobre muestras de electrodos nano-espaciados fabricados mediante la técnica de enmascaramiento con óxido de cromo. Se concluyó que estos dispositivos son una plataforma confiable para un amplio rango de temperaturas ($4$-$300$ K). Más aún, se pudo establecer que son compatibles tanto con técnicas actualmente disponibles como drop-casting, como con nuevas técnicas como la deposición directa de clústeres generados por pulverización catódica con magnetrón. La caracterización eléctrica de las nanopartículas de \ce{CoFe} PBA depositadas por \textit{drop-casting}, permitió demostrar que es posible atraparlas y estudiar sus curvas corriente-voltaje usando los dispositivos fabricados. Sin embargo, los datos obtenidos a bajas temperaturas no permitieron esclarecer el mecanismo involucrado en el transporte eléctrico. En este sentido es importante mencionar que se observaron dos comportamientos: Un primer grupo de dispositivos que no mostró evidencia de ser afectado por el láser ($640$ nm) y que presentó un \textit{Coulomb gap}, sugiriendo transporte individual de electrones; y un segundo grupo en el que si se evidenció un efecto tras la irradiación, que no se presenta \textit{Coulomb gap}, y cuya dependencia en temperatura de la resistencia se desvió fuertemente de la ecuación de Arrhenius ($\log(R) \propto T^{-1}$). En el caso de las nanopartículas a base de hierro, se consideró un nuevo esquema de fabricación y depósito de éstas, utilizando pulverización catódica. Mediciones a temperatura ambiente indicaron que las nanopartículas habían sido atrapadas entre los electrodos tras depositarlas. Las mediciones a baja temperatura mostraron una disminución en la resistencia medida y la aparición de un \textit{Coulomb gap}, lo que sugiere transporte individual de electrones. Usando teoría ortodoxa, y la aproximación de condensador de placas paralelas, fue posible estimar que el tamaño del punto de contacto entre la nanopartícula y los electrodos estaba en el rango de $1$ a $2$ nm, lo cual tiene sentido dado el tamaño de las primeras. / Este trabajo ha sido financiado a través de los Proyectos Fondecyt 1140770 y DAFNEOX

No description available.

Essential hypertension is the leading contributor to premature death worldwide. Endoplasmic reticulum (ER) stress has recently been implicated in diseased blood vessels and hypertension. It is unclear whether ER stress is a cause or a consequence of hypertension. We hypothesized that ER stress inhibition would prevent the development of hypertension in the young spontaneously hypertensive rat (SHR) by improving vascular structure and function. The SHR was used as a genetic model of human essential hypertension, and the Wistar Kyoto (WKY) rat as its normotensive control. The first study conducted involved assessing the levels of ER stress in young SHRs, before they developed hypertension. The second study conducted involved treating rats with 1g/kg/day of the sodium salt of 4-phenylbutyric acid (4-PBA) orally for 8 weeks from 5 weeks of age. Blood pressure was measured weekly, noninvasively via radiotelemetry. Mesenteric arteries were collected at sacrifice. Finally, the third study conducted involved treating rats with 1g/kg/day 4-PBA orally for eight weeks from five weeks of age, and then withdrawing the drug for four weeks to determine if drug treatment created a sustained lowering of blood pressure. In the first study, ER stress markers were observed to be significantly increased in the young SHR when compared to the WKY. In the second study, blood pressure was observed to be significantly lower in the 4-PBA-treated SHR groups than in the untreated SHRs. In addition, mesenteric arteries from the 4-PBA treated SHRs had a significant decrease in media/lumen ratio, ER stress marker expressions, as well as improved vasodilatory response to carbachol and reduced contractile responses to phenylephrine. In the third study, 4-PBA was able to keep the blood pressure low for one week after withdrawal, however, blood pressure returned to similar levels as untreated SHRs by the end of three weeks. Overall, ER stress inhibition, via 4-PBA, blunted the development of hypertension in the SHR. / Thesis / Master of Science (MSc)

Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2016-07-27T13:00:37Z No. of bitstreams: 1 arquivototal.pdf: 2786590 bytes, checksum: 78ef8677e696433a749f7ec4fc68899c (MD5) / Made available in DSpace on 2016-07-27T13:00:37Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2786590 bytes, checksum: 78ef8677e696433a749f7ec4fc68899c (MD5) Previous issue date: 2015-12-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Teaching act, understood as a work, is something that requires an understanding of the multidimensionality constitutive of teaching activity, considered by a sociointeractionist view, which allows to evaluate the individual actions as a reflection of their conceptions/representations built and/or acquired in the social environment. This research focuses on the epistemological approach of the Sociodiscursive Interactionism (SDI) and its main theoretical and methodological contributions, with the assumptions of Bronckart (1999; 2006; 2008); the Work Sciences (the Ergonomy and the Clinic of Activity) , the studies of Clot (2007; 2010); Nouroudine (2002) and Amigues (2004); and Education theories specifically regarding the Didactics, with studies of Tardif (2014); Chevallard (1991; 2013); Aeby-Daghé & Dolz (2008) and Schneuwly (2000). The investigation of this research is focused on the act of the literacy-teacher who works in the Brazil Literacy Programme (Programa Brasil Alfabetizado - PBA). The goal is to understand the teaching practice of literacy-teacher in the context of Youth and Adult Education (Educação de Jovens e Adultos – EJA), considering the relationship between the didactic gestures and teaching knowledge presented in their conceptions and their performances. This aim, based on this relation, is to investigate to what extension an analysis of literacy-teachers’ act in teaching young and old students can reveal their knowledge, specific gestures and practices. In this research, there are two collaborators who work in the PBA at urban schools, in the municipality of Jacaraú-PB. The adopted methodological approach consists of three stages of analysis, including the represented/interpreted work and the performed work. Thus, the collection and provision of data necessarily were carried out through, firstly semi structured interviews to check the teachers’ conceptions and their implied knowledge; secondly, filming three classes of each collaborator to check and categorize didactic gestures mobilized by them. Thirdly, a simple self-confrontation session with both literacy-teachers in order to get their interpretations of the implemented pedagogical act. With all the data, each stage was analyzed separately, using as categories, the thematic content and the linguistic-discursive materialization proposed by the SDI, in Machado and Bronckart (2009), in addition to the founding didactic gestures defined by Aeby-Daghé & Dolz (2008). In the end, there was a triangulation of data, bringing together all realization, in order to get a more accurate view of the investigated object. As conclusions, it was found that there are eight evidenced conceptions in the literary-teachers of the PBA, which are in the base of their specific didactic gestures’ performance. In addition, the interpretations of their own act reveal that the higher is the teaching experience, the higher is the tendency of the educator to shield him/herself and avoid explicitly self-reflections that expose his/her weaknesses and unexpected actions in their pedagogical activity. Therefore, as a result of all the analysis after triangulation, it was found that experiential knowledge derived from practice in the classroom is what permeates and guides the generation, doing and interpretation of these literacy-teachers of young people and adults. This fact confirms the thesis that pedagogical practice of the literacy-teachers of young and adult students in the Literate Brazil Program is permeated by didactic gestures and acquired and (re)focused knowledge, mainly in / by the experience in the classroom. / O agir docente, entendido como trabalho, é algo que requer uma compreensão da multidimensionalidade constitutiva da atividade de ensino, vista por uma ótica sociointeracionista, a qual permite avaliar as ações dos indivíduos como sendo reflexo de suas concepções/representações construídas e/ou adquiridas no social. A presente pesquisa centra-se nessa abordagem epistemológica e tem como principais aportes teórico-metodológicos o Interacionismo Sociodiscursivo – ISD, com os pressupostos de Bronckart (1999; 2006; 2008); as Ciências do Trabalho (Ergonomia e Clínica da Atividade), com os estudos de Clot (2007; 2010); de Nouroudine (2002) e de Amigues (2004); e as Teorias da Educação, especificamente, relativas à Didática, com os estudos de Tardif (2014); Chevallard (1991; 2013); Aeby-Daghé & Dolz (2008) e Schneuwly (2000). O objeto de investigação é o agir do professor-alfabetizador de Jovens e Adultos atuante no Programa Brasil Alfabetizado (PBA). O objetivo central é compreender a prática pedagógica dos professores-alfabetizadores em contexto de EJA, considerando a relação entre os gestos didáticos e os saberes docentes presentes em suas concepções e realizações do agir. Tal objetivo resulta da problemática que é investigar em que medida uma análise do agir docente do alfabetizador de jovens e adultos pode revelar saberes, gestos e práticas específicas desse professor. Participam da pesquisa dois professores colaboradores que atuam no PBA, no município de Jacaraú-PB, em escolas da zona urbana. O percurso metodológico adotado é composto de três momentos de análise, incluindo o trabalho representado/interpretado e o trabalho realizado. Assim, a constituição dos dados correspondeu necessariamente a tal percurso, a saber, primeiro, a realização de entrevistas semiestruturadas para verificar as concepções docentes e os saberes nelas implicados; segundo, a filmagem de três aulas de cada colaborador para verificar e categorizar os gestos didáticos por eles mobilizados; e terceiro, uma sessão de autoconfrontação simples com ambos os alfabetizadores a fim de obter as suas interpretações acerca do agir pedagógico implementado. De posse do conjunto dos dados, fez-se a análise de cada etapa, separadamente, utilizando como categorias o nível do conteúdo temático e o da materialização linguístico-discursiva propostos no quadro do ISD, conforme Machado e Bronckart (2009), além dos gestos didáticos fundadores definidos por Aeby-Daghé & Dolz (2008). Ao final, fez-se uma triangulação dos dados, reunindo todas as constatações, com o propósito de obter uma visão mais apurada do objeto investigado. Como conclusões, verificou-se a existência de oito concepções docentes evidenciadas no dizer dos alfabetizadores do PBA, as quais estão na base da realização dos seus gestos didáticos específicos. Além disso, as interpretações do próprio agir feitas pelos respectivos professores revelam que, quanto maior a experiência docente, mais o educador tende a evitar explicitamente autorreflexões que desvelem as fragilidades e os imprevistos do seu agir professoral. Portanto, como desdobramentos de todas as análises, após a triangulação, ficou constatado que os saberes experienciais oriundos da prática em sala de aula são o que perpassa e orienta tanto o conceber, quanto o fazer e o interpretar desses alfabetizadores de pessoas jovens e adultas. Esse fato serviu para confirmar a tese de que a prática pedagógica do alfabetizador de jovens e adultos atuante no Programa Brasil Alfabetizado é permeada por gestos didáticos e saberes docentes adquiridos e (re)orientados, sobretudo, na/pela vivência em sala de aula.

Introduction The genetic skin disease epidermolytic ichtyosis is caused by mutations in either keratin gene 1 or 10 and leads to blisters and hyperkeratosis of the epidermis. At cellular level the disease is seen as aggregates in the keratin filaments. Since medicines are hard to investigate and produce mainly due to lack of reproducible model systems, there is no good treatment available for this disease today. In this article we describe how an in vitro model consisting of cells from a stable cell line transfected with expression plasmids to mimic patient cells, may be a possible alternative for screening compounds for therapies. The first step was to generate an expression plasmid required to complete the in vitro model. The model was tested by a preliminary experiment with 4-phenylbuturate (4-PBA) to see if the substance had an effect on the amount of cells with keratin aggregates. Methods PCR and primers containing the desired mutation were used to incorporate a deletion in wild type keratin gene1 plasmid to generate the expression plasmid. HaCaT cells were transfected with the plasmid for expression of keratin. The percentage of cells with keratin aggregates was assessed by fluorescence microscopy. Results/Conclusion Cells containing mutated plasmid had a higher percentage of keratin aggregates compared to cells transfected with wild type plasmid. 4-PBA was found not to affect the amount of cells with keratin aggregates. According to this project the model might be a useful tool for screening compounds, but it needs to be more developed and tested.

No description available.

La mucoviscidose est une pathologie pulmonaire causée par un dysfonctionnement du canal CFTR et caractérisée par un mucus visqueux, une susceptibilité accrue aux infections chroniques et une inflammation excessive. Une première partie de ma thèse a eu pour objectif d’étudier les mécanismes inflammatoires impliqués dans le développement de la pathologie. Nous avons plus particulièrement analysé le rôle de l’IL-1β et de l’IL-17 dans la réponse à l’infection par Pseudomonas aeruginosa, dans le modèle murin ΔF508 de mucoviscidose. La seconde partie de ma thèse a porté sur l’étude de la malaria pulmonaire et cérébrale, une complication létale de l’infection à P. falciparum. Nous avons mis en évidence l’importance de trois voies d’activation des lymphocytes T CD8+ cytotoxiques dans le développement de la neuropathologie induite par Plasmodium berghei ANKA chez la souris : la protéine PKC-θ, la sous-unité β2 du récepteur à l’IL-12 et le récepteur des IFN de type I, mais qui ne semblent pas impliquées dans l’inflammation pulmonaire associée. / Cystic fibrosis is a pulmonary pathology, caused by the CFTR channel dysfunction, and characterized by high mucus viscosity, increased sensitivity to chronic infections and excessive inflammation. The aim of my thesis was first to study the inflammatory mechanisms involved in this lung pathology. Indeed, we analyzed the role of IL-1β and IL-17 in response to Pseudomonas aeruginosa infection, in the ΔF508 mouse model of cystic fibrosis. In the second part of my thesis, I studied pulmonary and cerebral malaria, a lethal complication of P. falciparum infection. We showed the importance of three pathways implicated in cytotoxic CD8+ T lymphocytes activation during the Plasmodium berghei ANKA-induced neuropathology development in mice: PKC-θ protein, β2 subunit of IL-12 receptor and type I IFN receptor, which did not seem essential for the associated lung inflammation.

The aim of this thesis is to determine the sources, controls and risk aspects of fluoride in surface water and groundwater in a region of southeastern Sweden where the fluorine-rich 1.45 Ga circular Götemar granite (5 km in diameter) crops out in the surrounding 1.8 Ga granites and quartz monzodiorites (TIB rocks). The materials of this thesis include both primary data, collected for the purpose of this thesis, and a large set of secondary data, retrieved from the Swedish Nuclear Fuel and Waste Management Co., the Swedish Geological Survey and the Kalmar County Council. A characteristic feature of the area is high fluoride concentrations in all kinds of natural waters, including surface waters (such as streams) and groundwater in both the Quaternary deposits (regolith groundwater) and bedrock fractures (fracture groundwater). A number of potential sources and controls of the high fluoride concentrations were investigated, including a variety of geological, mineralogical, mineral-chemical and hydrological features and processes. For the stream waters and regolith groundwater, high fluoride concentrations were correlated with the location of the Götemar granite. This finding is explained by the discharge of fluoride-rich groundwater from fractures in the bedrock and/or the release of fluoride due to the weathering of fluorine-bearing minerals in the Quaternary deposits; however, the Quaternary deposits had considerably lower fluoride concentrations than the underlying bedrock. The high fluoride concentrations in the fresh fracture groundwater (up to 7.4 mg/L) in the TIB-rocks are proposed to be the result of long residence times and the alteration/dissolution of fluorine-bearing primary and secondary minerals along the fracture walls. In terms of risk aspects, this thesis shows that fluoride can add to the transport and inorganic complexation of aluminium in humic-rich, acidic streams. Additionally, 24 % of the children in households with private wells in Kalmar County were assessed to be at risk of excess fluoride intake based on the WHO drinking water guideline value (1.5 mg/L). However, the risk increased significantly when instead the US EPA reference dose (0.06 mg/kg-day) was used, both when all relevant exposure pathways were taken into account as well as water consumption alone. Hence, it is shown that the risk of an excess intake of fluoride is strongly dependent on the basis for evaluation.

La perméthrine fait partie de la famille des pyréthrinoïdes qui sont abondamment utilisés en agriculture. Le but de cette étude était d'obtenir des données sur la cinétique des biomarqueurs d'exposition à la perméthrine en condition réelle d'exposition chez les travailleurs agricoles. Douze travailleurs (un applicateur, un superviseur et dix cueilleurs) exposés à la perméthrine dans le cadre de leur emploi ont été recrutés dans une ferme maraichère de la Montérégie (Québec). Ils ont fourni toutes leurs urines sur une période de trois jours suivant le début des travaux dans un champ traité. Les trois principaux métabolites de la perméthrine, l'acide cis-/trans-3-(2,2-dichlorovinyle)-2,2-diméthylecyclopropane carboxylique (cis-/trans-DCCA) et l'acide 3-phénoxybenzoïque (3-PBA) ont été analysés par chromatographie liquide à ultra-haute performance couplée à la spectrométrie de masse à temps de vol. Pour l'applicateur, une augmentation progressive des valeurs d'excrétion a été observée avec un pic unique atteint environ 30 h après le début de l'exposition d'une durée de 3,5 h suivi d'une élimination avec une demi-vie de 8 h. Pour le superviseur et l'un des cueilleurs, les profils d'excrétion de trans-DCCA et de 3-PBA étaient compatibles avec de multiples entrées dans la zone traitée pendant la période d'échantillonnage accompagné d'une élimination rapide entre les épisodes d'exposition.L'applicateur aurait été exposé indirectement par contact main-bouche, alors que les autres travailleurs auraient été exposés par la voie cutanée. Pour une surveillance biologique adéquate, nous recommandons de mesurer deux biomarqueurs de la perméthrine, soit le trans-DCCA et le 3-PBA et de prendre un minimum de trois échantillons urinaires, un avant et deux pendant ou suivant la période d'exposition. / Permethrin is a synthetic pyrethroid insecticide widely used in agriculture worldwide. This study aimed at obtaining data on the time courses of biomarkers of exposure to permethrin in agricultural workers following typical exposure conditions. Twelve workers (an applicator, a supervisor and ten harvesters) exposed to permethrin were recruited from a corn production farm in the Montérégie (Quebec). They provided all their urine voided over a period of three days following the onset of a spraying episode of permethrin or work in a treated area. Three major metabolites of permethrin, cis-/trans-3-(2,2-dichlorovinyl)-2,2-dimethylycyclopropane carboxylic acid (cis-/trans-DCCA) and 3-phenoxybenzoic acid (3-PBA) were analyzed by ultra-high performance liquid chromatography coupled to quadripole time-of-flight mass spectrometry (UHPLC/Q-TOF MS). For the applicator, a progressive rise in excretion values was observed with a single peak being reached about 30 h following the onset of the 3.5 h exposure and ensuing elimination with a half-life of 8 h. For the supervisor and one harvester excretion profiles of trans-DCCA and 3-PBA were more compatible with multiple entries in the treated area during the 3-day sampling period and rapid elimination between exposure episodes. The applicator would have been indirectly exposed by hand-to-mouth contact, while other workers would have been exposed by the dermal route. Time-dependent variability in excretion values of workers confirms the need for serial urine sampling of at least two biomarkers of exposure for routine biomonitoring, with minimally pre-exposure, end-of-shift sample the day of the onset of exposure and following morning void.

Made available in DSpace on 2015-05-07T15:08:45Z (GMT). No. of bitstreams: 1 Arquivototal.pdf: 1371028 bytes, checksum: 2a18f3848ddc48fc8054a0cb273598f8 (MD5) Previous issue date: 2012-08-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This report is based on both qualitative and quantitative data resulting from bibliographical, documental and fieldwork research carried out in fifteen municipalities in the 9th Microregion of the backlands (sertão) of the State of Paraiba. The research analyses the impact of the Literate Brazil Programme (PBA) on public policy for youth and adult education (YAE) in these municipalities. It seeks to understand what perspectives guide public policy of Youth and Adult education, characterizing its provision and linkages with the Literacy Programme with a view to guarantee continuity of studies for those concluding PBA. To that end, studies on PBA, documents which regulate literacy activities and the provision of YAE by the state and municipal systems, statistical data from the School Census (Censo Escolar) (the historical series 2003-2010) which register enrolments in this modality in the 15 municipalities, were consulted. Fieldwork was undertaken to collect information from local managers (municipal secretaries and coordinators of AYE) using semi-structured interviews. On the basis of our analysis, we conclude that the Literate Brazil Programme introduces possibilities for the planning, systematization and instrumentalization of municipal public policy. On the negative side, we point to the fact that the provision of literacy classes by PBA has inhibited the provision of adult literacy classes by the school networks (state and municipal) in the municipalities under study. With regard to the linkage between the demand produced by PBA and the provision of schooling by the state and municipal systems of education, we point to the absence of an effective educational policy formulated on the basis of the specificities of YAE as a modality of primary education. Our analysis is based on the following authors, amongst others: Arretche (2000), Arroyo (2005, 2007) Azevedo (2004), Carnoy (1994), Ireland (2009, 2012), Fávero (2011), Freire (1996, 2011), Machado (2009, 2011), Minayo (2005, 2009). / O presente trabalho compreende um estudo de natureza qualitativa e quantitativa, baseado em pesquisa bibliográfica, documental e de campo, realizada em quinze municípios da 9ª microrregião do sertão paraibano. O objeto da investigação é analisar o impacto do Programa Brasil Alfabetizado (PBA) para as políticas públicas da Educação de Jovens e Adultos (EJA) nesses municípios. A pesquisa busca compreender quais as perspectivas que norteiam as políticas públicas para EJA caracterizando sua oferta e articulação com o PBA na perspectiva de garantir a continuidade para os egressos do referido Programa. Para tanto, buscaram-se estudos já empreendidos sobre o PBA, documentos que normatizam as ações de alfabetização e oferta da EJA pelas redes estadual e municipal, dados estatísticos tendo por base o Censo Escolar (série histórica de 2003 a 2010), evidenciando as matrículas desta modalidade nos quinze municípios. A pesquisa de campo objetivou coletar informações através de gestores locais (secretários e coordenadores municipais da EJA) por meio de entrevistas semiestruturadas. A partir da análise constatou-se que o PBA vem apresentando possibilidades de planejamento, sistematização e instrumentalização para as políticas públicas municipais. Como aspecto negativo destacamos que a oferta das turmas de alfabetização pelo PBA vem inibindo a oferta da alfabetização na modalidade EJA pelas redes de ensino (municipal e estadual) dos municípios pesquisados. No tocante à articulação entre a demanda oriunda do PBA e a oferta de escolarização nas redes estadual e municipal de ensino, apontase a ausência de uma política educacional efetiva, formulada com base nas especificidades da EJA, enquanto modalidade do ensino fundamental. As análises estão fundamentadas, dentre outros, em autores como Arretche (2000), Arroyo (2005, 2007), Azevedo (2004), Carnoy (1994), Ireland (2009, 2012), Fávero (2011), Freire (1996, 2011), Machado (2009, 2011), Minayo (2005, 2009).