Le vieillissement cutané s'accompagne d'altérations des composants de la matrice extracellulaire. Des études ont montré que le contenu en collagène IV diminuait dans la peau à partir de 35 ans. Le collagène IV, constituant majeur des membranes basales, est formé de l'association, en triple hélice, de 3 chaînes alpha parmi 6 possibles: alpha1(IV) à alpha6(IV). Au niveau de la membrane basale cutanée, encore appelée jonction dermo-épidermique, seulement deux isoformes de collagène IV ont été mises en évidence : [alpha1(IV)2; alpha2(IV)], isoforme majoritaire, et [alpha5(IV)2; alpha6(IV)], isoforme minoritaire, synthétisées par les fibroblastes et les kératinocytes. Nous avons vérifié, par western-blot sur des extraits de peaux, cette diminution de collagène IV. Nous avons ensuite analysé la répartition du collagène IV au niveau de la JDE sur des coupes transversales de peau et n'avons pu mettre en évidence de discontinuité dans le réseau de collagène IV avec l'âge, du fait des fortes variations inter-individuelles. Parallèlement, sur coupe de peau, nous avons tenté de mettre en évidence des différences spectrales du collagène IV avec l'âge par spectroscopie Raman mais la résolution s'est avérée insuffisante. Nous avons isolé des fibroblastes de patients d'âges différents et montré une diminution de l'expression génique de la chaîne alpha1(IV) malgré de fortes variations inter-individuelles. Afin de s'affranchir de ces variations inter-individuelles pour étudier les mécanismes impliqués dans la diminution d'expression du collagène IV, nous avons mis au point un modèle de vieillissement accéléré de fibroblastes traités à l'H2O2 et vérifié le phénotype sénescent des cellules (morphologie modifiée, augmentation de l'activité SA-beta-galactosidase, augmentation de p21WAF-1…). Nous nous sommes intéressé à la voie du TGF-beta1. Nous avons montré que l'expression du récepteur au TGF-beta1, TbetaRII, diminuait dans le modèle de vieillissement accéléré. Nous avons également montré qu'un anticorps bloquant anti-TGF-beta1 reproduisait la diminution d'expression de collagène IV observée au cours de la sénescence. La détermination du mécanisme impliqué pourrait permettre, à terme, de proposer de nouvelles stratégies pour maintenir l'intégrité de la membrane basale lors du vieillissement cutané. / During aging skin there are extracellular matrix alterations. Preliminary studies showed that type IV collagen content decreased in skin with age after 35 years. Type IV collagen is a major component of basement membranes. It's constituted by the association of 3 alpha chains among 6 possible (alpha1 to alpha6). In the cutaneous basement membrane also called dermo-epidermal junction, only two isoform of type IV collagen were found: [alpha1(IV)2; alpha2(IV)], which is majoritary isoform, and [alpha5(IV)2; alpha6(IV)], which is minoritary, both synthesized by fibroblasts and keratinocytes. We checked the decrease in type IV collagen by western-blot on skin extracts. We then analyzed the distribution of this collagen in the DEJ on skin sections but we were not able to highlight a discontinuity in the network of type IV collagen during aging. At the same time, we tried to highlight spectral differences of the collagen IV with aging by Raman spectroscopy on skin sections but the resolution was insufficient. 35 years. We showed a decrease of type IV collagen expression by dermal fibroblasts in spite of strong variation between patients. In order to study the mechanism involved in type IV collagen variation during aging in dermal fibroblasts avoiding inter-individual variations, we develop an accelerated aging model of fibroblasts by treatment with H2O2. We checked the senescent phenotype of the cells (modified morphology, increase of SA-beta-galactosidase activity, increase of p21WAF-1…). We were interested on the TGF-1 pathway and we showed that TGF-beta1 receptor, called TbetaRII, was decreased in our accelerated aging model. We also showed that a blocking antibody against TGF-beta1 reproduced the decrease of type IV collagen expression observed during the senescence. The determination of the involved mechanism could lead to propose new strategies to maintain the integrity of the basal membrane during skin aging.

This work concentrates on the issue of capital adequacy of banks. Inadequate capital base of the banking sector is often referred to as one of the causes of the latest financial crisis. Such topic is currently very actual. Even banking regulators pay high attention to this topic. In my thesis I focus on legal and economic aspects of this topic. It is typical for the banking sector that banks operate with much more leverage effect than enterprises belonging to other sectors. Therefore, I focus on the root cause of this phenomenon in the third chapter. I assess the bank indebtedness using the theory of optimal capital structure and I also address the relations between economic and regulatory capital. In the fourth chapter I focus on the concept of capital adequacy and its comparison with leverage indicator. The next chapter concentrates on the development of regulatory minimum capital adequacy standards developed by the Basel Committee on Banking Supervision, known as Basel I and Basel II. The last but one chapter focuses on the latest regulatory rules Basel III governing the capital adequacy of banks and their legal implementation. Final chapter analyzes the impact of Basel III rules on the capital structure of banks in the European Union and the Czech Republic. A separate part of the chapter is...

Este trabalho propõe a tradução do discurso Panegírico, de autoria do ateniense Isócrates. A versão vem acompanhada de notas, que visam a fornecer um breve comentário das passagens mais importantes do texto. Um estudo introdutório, cujo primeiro capítulo pretende discutir algumas questões propostas pelo texto, tratando de sua composição, do tratamento dos fatos históricos e um breve relato das principais interpretações modernas do Panegírico. O capítulo seguinte aborda o problema dos bárbaros no Panegírico e como o retrato de Isócrates dos povos não gregos visa a reforçar as propostas feitas pelo autor em seu texto. Na parte final do estudo, examina-se a relação desse texto com obras precedentes tratando das mesmas questões que o Panegírico. / This work proposes to translate the Panegyricus, a speech by the Athenian Isocrates. Endnotes have been added, in order to comment the most important passages in the text. In addition, an introductory study is included to clarify the some points of the text, such as the problems posed by the composition of the text, its treatment of the historical facts and a brief review of the main modern interpretations of the Panegyricus. The next chapter discusses the role which the barbarians play in the Panegyricus and how Isocrates portrait of the non-Greek peoples serves the propositions advanced by the author in his text. The final part of the study examines the relation of the Panegyricus with texts treating the same questions.

As cucurbiturilas são moléculas versáteis empregadas em diversos ramos da química, essas gaiolas moleculares formam uma família de homólogos oriundos da condensação da glicolurila e do formaldeído em meio ácido. As aplicações se estendem para campos como catálise, fotoquímica, sínteses orgânica e inorgânica, química de materiais e supramolecular. Particularmente a cucurbit[6]urila, comumente chamada apenas de CB[6], uma molécula bastante simétrica, têm em seus opérculos, sítios propícios à coordenação, especialmente com espécies pequenas e pouco polarizáveis. Aproveitando o caráter dos portais, foi possível sintetizar um complexo inédito, com um sítio catalítico proveniente de íons vanadila, VO2+, ligados às extremidades do cavitando. O acesso ao centro catalítico desta molécula, seria determinado pela captura do substrato no interior do macrociclo, limitado pelo volume do substrato e pelas relações de solvofobicidade, pois a cavidade possui um caráter hidrofóbico. A estrutura desse complexo ainda não foi completamente elucidada, pois não foi possível obter um cristal único e determiná-la através de difração de raios-x. As técnicas de caracterização no estado sólido empregadas indicaram que esse novo complexo teria o seu centro metálico provavelmente numa configuração piramidal de base retangular, isso é evidenciado pelas medidas espectroscópicas que remetem a uma simetria C2V. Foram feitas tentativas de coordenação mono e binuclear, mas algumas técnicas apontam para a formação apenas da espécie mononuclear. Os primeiros testes catalíticos, em condições brandas para a conversão de hidrocarbonetos apresentaram bons resultados frente a substratos lineares e inatividade frente a substratos cíclicos mais volumosos. Os resultados obtidos nos levam a crer que as reações de oxidação de alcanos, com estas espécies, se dão pelo interior da cavidade, ao longo do orbital dz2 do íon (V=O)2+, e não pela parte superior através do átomo de oxigênio ligado ao vanádio. / Cucurbiturils are versatile molecules used in several branches of chemistry. These molecular cages form a family of homologues from the condensation of glycoluril and formaldehyde in acidic medium. Their applications range from catalysis, photochemistry, organic and inorganic synthesis, materials and supramolecular chemistry. Particularly cucurbit[6]uril, or simply CB[6], is a very symmetrical molecule, which posesses coordination points on its portals, especially with hard acids. Due to this characteristic, it was possible to synthesize a new complex, with a vanadyl, VO2+, catalytic center bonded to the extremity of the cavitand. The access to the catalytic center of this molecule should be determined by the entrance of the substrate inside the macrocycle, which is limited by its volume and by solvophobicity, because the cavity is strongly hydrophobic. The structure of this new complex could not be completely solved yet, because it was impossible to obtain a single crystal for X-rays diffraction analysis. The solid state characterization techniques indicated that this new complex has its metallic center in a rectangular-base pyramid configuration. This was shown by the spectroscopic evidences which point to a d1 ion in a C2V symmetry. Attempts were made to synthesize both mono and binuclear species, but all the techniques we have used have demonstrated that only the former one was obtained. The first catalytic tests for hydrocarbons convertion in mild conditions have shown good results towards for linear substrates and no activity at all towards more volumous cyclic molecules. The results we have obtained indicate that the alkane oxidation reactions with these complexes occur inside the cavity along the (V=O)2+ ion dz2 orbital , and not on its superior moiety on the vanadyl oxygen atom.

abstract: The work described in this thesis explores the synthesis of new semiconductors in the Si-Ge-Sn system for application in Si-photonics. Direct gap Ge1-ySny (y=0.12-0.16) alloys with enhanced light emission and absorption are pursued. Monocrystalline layers are grown on Si platforms via epitaxy-driven reactions between Sn- and Ge-hydrides using compositionally graded buffer layers that mitigate lattice mismatch between the epilayer and Si platforms. Prototype p-i-n structures are fabricated and are found to exhibit direct gap electroluminescence and tunable absorption edges between 2200 and 2700 nm indicating applications in LEDs and detectors. Additionally, a low pressure technique is described producing pseudomorphic Ge1-ySny alloys in the compositional range y=0.06-0.17. Synthesis of these materials is achieved at ultra-low temperatures resulting in nearly defect-free films that far exceed the critical thicknesses predicted by thermodynamic considerations, and provide a chemically driven route toward materials with properties typically associated with molecular beam epitaxy. Silicon incorporation into Ge1-ySny yields a new class of Ge1-x-ySixSny (y>x) ternary alloys using reactions between Ge3H8, Si4H10, and SnD4. These materials contain small amounts of Si (x=0.05-0.08) and Sn contents of y=0.1-0.15. Photoluminescence studies indicate an intensity enhancement relative to materials with lower Sn contents (y=0.05-0.09). These materials may serve as thermally robust alternatives to Ge1-ySny for mid-infrared (IR) optoelectronic applications. An extension of the above work is the discovery of a new class of Ge-like Group III-V-IV hybrids with compositions Ga(As1–xPx)Ge3 (x=0.01-0.90) and (GaP)yGe5–2y related to Ge1-x-ySixSny in structure and properties. These materials are prepared by chemical vapor deposition of reactive Ga-hydrides with P(GeH3)3 and As(GeH3)3 custom precursors as the sources of P, As, and Ge incorporating isolated GaAs and GaP donor-acceptor pairs into diamond-like Ge-based structures. Photoluminescence studies reveal bandgaps in the near-IR and large bowing of the optical behavior relative to linear interpolation of the III-V and Ge end members. Similar materials in the Al-Sb-B-P system are also prepared and characterized. The common theme of the above topics is the design and fabrication of new optoelectronic materials that can be fully compatible with Si-based technologies for expanding the optoelectronic capabilities of Ge into the mid-IR and beyond through compositional tuning of the diamond lattice. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2018

As pesquisas atuais sobre os sambaquis litorâneos no Brasil os consideram estruturas intencionalmente construídas a partir de unidades culturais complexas, de processo contínuo de sedentarização e adensamento demográfico, que se expandiram por toda a costa brasileira entre pelo menos sete mil e mil e quinhentos anos atrás. Após esse período de dominação sambaquieira em ecossistemas costeiros, ocorreu um processo de mudança na configuração dos sítios, marcado pela presença de cerâmica em camadas mais recentes dos sambaquis e pelo surgimento de novos assentamentos tardios. Tais transformações são interpretadas como o início do contato entre povos interioranos e as populações do litoral. Essa pesquisa de mestrado buscou aprofundar o conhecimento obtido a respeito do sítio cerâmico Galheta IV (datado entre 1256-1031 e 690-530 cal AP) durante o projeto Sambaquis e Paisagem, a partir de uma perspectiva zooarqueológica, e trazer novos dados que auxiliem na compreensão dos processos de descontinuidade da construção de sítios conchíferos no litoral sul catarinense. As análises contemplaram áreas intra-sítio na tentativa de compreender sua contextualização relacional e espacial. Os resultados identificaram vestígios zooarqueológicos atuando como acompanhamentos funerários. Uma concentração de vestígios de fauna em uma área específica do sítio arqueológico, associada à grande quantidade concreções, apontam para um alto processamento e consumo de vertebrados relacionados ao contexto funerário do sítio. A presença significativa de espécies marinhas de grande porte, como pinípedes, tubarões, e cetáceos, somados aos resultados de análises isotópicas previamente desenvolvidas, inaugura um panorama que difere dos demais estudos de fauna em sítios costeiros desenvolvidas até então, nos quais os peixes são fontes proteicas predominantes na dieta de populações pré ceramistas e ceramistas. Esses animais marinhos de elevado nível de cadeia trófica, somados aos peixes, aves e tartarugas marinhas, demonstram uma continuidade e intensificação das práticas pesqueiras desenvolvidas por grupos sambaquieiros, numa adaptação para a captura de recursos junto às áreas próximas ao costão rochoso e ao mar aberto. / Current research on the coastal shellmounds (or sambaquis) in Brazil considers them structures intentionally constructed from complex cultural units, a continuous process of sedentarization and demographic densification, which have expanded throughout the Brazilian coast between at least seven thousand and fifteen hundred years ago. After this period of shellmounds domination in coastal ecosystems, a process of change in the configuration of the sites occurred, marked by the presence of pottery in more recent layers of the shellmounds and by the appearance of new late settlements. Such transformations are interpreted as the beginning of contact between the interior peoples and the coastal populations. This master\'s research sought to deepen the knowledge obtained about the Galheta IV ceramic site (dating from 1256-1031 and 690-530 cal BP) during the Sambaquis e Paisagem project, from a zooarchaeological perspective, and to bring new data that contribute to the understanding of the discontinuity processes of the construction of shellmounds sites in the south coast of Santa Catarina. Analyzes contemplated intra-site areas in an attempt to understand their relational and spatial contextualization. The results identified zooarchaeological vestiges acting as funerary accompaniments. A concentration of fauna remains in a specific area of the archaeological site, associated to a large number of concretions, point to a high processing and consumption of vertebrates related to the funerary context of the site. The significant presence of large marine species, such as pinnipeds, sharks, and cetaceans, added to the results of previously developed isotopic analyzes, inaugurates a panorama that differs from other studies of fauna in coastal sites developed until then, in which fish are protein sources predominant in the diet of pre-ceramic and ceramic populations. These marine animals of high trophic chain, in addition to fish, birds and sea turtles, demonstrate a continuity and intensification of the fishing practices developed by sambaquis people, in an adaptation for the capture of resources near the rocky coast and the open sea.

A família é um sistema dinâmico e complexo influenciado por aspectos históricos, econômicos, políticos, sociais e culturais. As relações familiares, em algum grau, podem interferir nos processos de saúde e doença de seus membros, assim como a interpretação da experiência de cada indivíduo da família diante desses eventos. Avaliar o sistema familiar, assim como avaliar como ocorre sua dinâmica favorece possíveis intervenções nesse campo, podendo prevenir enfermidades e/ou sofrimento dos sujeitos que fazem parte desse sistema. O objetivo deste estudo foi verificar a associação de variáveis sociodemográficas (sexo, situação ocupacional, religião e classe socioeconômica) e de caraterísticas familiares (tipo de família e presença/ausência de doença crônica) sobre a percepção de funcionamento familiar em universitários. Este estudo foi do tipo descritivo, exploratório, de corte transversal, apoiado na metodologia quantitativa e de referencial sistêmico. Os dados foram coletados em estudantes universitários de uma universidade pública do interior do Estado de São Paulo e os instrumentos utilizados foram o questionário sociodemográfico e familiar e a escala de avaliação da coesão e adaptabilidade familiar (FACES IV). A análise de dados foi realizada com o programa SPSS 25.0 e foram realizadas medidas de tendência central e de dispersão para variáveis numéricas e calculadas as porcentagens para variáveis categóricas. Para a comparação de variáveis de interesse foi utilizado um teste estatístico específico (t de Student), adotando-se nível de significância p=0,05. Participaram do presente estudo 295 estudantes universitários de cursos de graduação da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (Medicina, Ciências Biológicas/Modalidade Médica, Terapia Ocupacional, Fisioterapia, Nutrição e Metabolismo e Fonoaudiologia). A maioria dos participantes pertencia ao Estado de São Paulo (90,5%), eram do sexo feminino (82,0%), pertencente à faixa etária dos 18 a 22 anos (93,6%), com ensino superior incompleto (96,9%), sem companheiro residindo na mesma residência (99,0%), não trabalhava (61,7%), morava com a família (41,4%), tinha como principal provedor o pai consanguíneo (65,4%), pertencia à família nuclear (75,3%), não possuía membro familiar com doença crônica (73,9%), de religião católica (68%) e pertencia à classe socioeconômica A. Não foram encontradas diferenças significativas entre o funcionamento familiar e as variáveis sociodemográficas elencadas, sugerindo que, na presente amostra, o sexo, a situação ocupacional, a religião e a classe socioeconômica possuem baixo poder explicativo sobre o modo como a família opera em termos de coesão, flexibilidade e comunicação. Com parcimônia, aventa-se que esses achados podem ser explicados em função da amostra homogênea e não exposta a vulnerabilidades sociais expressivas, com aspectos protetivos que envolvem, por exemplo, a alta escolarização, o pertencimento a uma universidade pública com rígida política seletiva de ingresso e também a vinculação a configurações familiares consideradas mais tradicionais, embora tais estruturas não devam ser tomadas como sinônimos de ajustamento psicossocial ou de funcionamento emocional adequado. Para estudos futuros, recomenda-se maior diversificação da amostra, bem como instrumentos de rastreio para saúde mental, abrangendo populações mais expostas a vulnerabilidades que possam estar associadas ao funcionamento familiar, ampliando as reflexões sobre os aspectos contextuais que podem repercutir no desenvolvimento do público universitário / The family is a dynamic and complex system influenced by historical, economic, political, social and cultural aspects. Family relationships, at some degree, may interfere with the health and illness processes of their members, as well as the interpretation of each individual\'s family\'s experience of these events. Evaluating the family system, as well as evaluating how its dynamics occurs, favors possible interventions in this field, and can prevent illnesses and/or suffering of the subjects that are part of this system. The objective of this study was to verify the association of sociodemographic variables (gender, occupational situation, religion and socioeconomic class) and family characteristics (family type and presence/absence of chronic disease) on the perception of family functioning in university students. This study was descriptive, exploratory, cross - sectional, supported by the quantitative methodology and the theoretical input used was the systemic approach. Data were collected from university students of a public university in the interior of São Paulo and the instruments used were the sociodemographic and family questionnaire and the scale of evaluation of family cohesion and adaptability (FACES IV). Data analysis was performed through the SPSS 25.0 program and measurements of central tendency and dispersion were performed for numerical variables and the percentages for categorical variables were calculated. For the comparison of variables of interest, a specific statistical test (Student\'s t) was used, adopting significance level p=0,05. A total of 295 undergraduate students from the Medical School of Ribeirão Preto of the University of São Paulo (Medicine, Biological Sciences/Medical Modality, Occupational Therapy, Physiotherapy, Nutrition and Metabolism and Speech Therapy) participated in this study. Most of the participants were from the State of São Paulo (90.5%), were females (82.0%), aged 18 to 22 years old (93.6%), with incomplete higher education (96 , 9%), had no partner living in the same household (99.0%), did not work (61.7%), lived with the family (41.4%), had as main provider the consanguineous father (65.4% ), belonged to the nuclear family (75.3%), did not have a family member with chronic disease (73.9%), the family religion was Catholic (68%) and belonged to socioeconomic class A. No significant differences were found between family functioning and sociodemographic variables, suggesting that in the present sample, gender, occupational situation, religion and socioeconomic class have low explanatory power on how the family operates in terms of cohesion, flexibility and communication. With parsimony, it is pointed out that these findings can be explained by the homogeneous sample and not exposed to expressive social vulnerabilities, with protective aspects that involve, for example, high schooling, belonging to a public university with a rigid selective admission policy and also the linkage to family configurations considered more traditional, although such structures should not be taken as synonyms of psychosocial adjustment or adequate emotional functioning. For future studies, a greater sample diversification is recommended, as well as screening tools for mental health, covering populations that are more exposed to vulnerabilities that may be associated with family functioning, broadening the reflections on the contextual aspects that may affect the development of the university public

<p>The use of hydrogen is predicted to increase substantially in the future, both as chemical feedstock and also as energy carrier for transportation. The annual world production of hydrogen amounts to some 50 million tonnes and the majority is produced using fossil fuels like natural gas, coal and naphtha. High temperature nuclear reactors (HTRs) represent a novel way to produce hydrogen at large scale with high efficiency and less carbon footprint. The aim of this master thesis has been to evaluate the feasibility of HTRs for hydrogen production by analyzing both the reactor concept and its potential to be used in certain hydrogen niche markets. The work covers the production, storage, distribution and use of hydrogen as a fuel for vehicles and aviation and as chemical feedstock for the oil refining and ammonia production industry.</p><p>The study indicates that HTRs may be suitable for hydrogen production under certain conditions. However, the use of hydrogen as an energy carrier necessitates a widespread hydrogen infrastructure (e.g. pipe-lines, refuelling stations and large scale storage), which is associated with major energy losses. Both mentioned industries could benefit from nuclear-based hydrogen with less infrastructural changes, but the potential market is by far smaller than if hydrogen is used as an energy carrier. A maximum of about 60 HTRs of 600 MWth worldwide has been estimated for the ammonia production industry. The Swedish refineries are likely too small to utilize the HTR but in the larger refineries HTR might be applicable.</p>

The use of hydrogen is predicted to increase substantially in the future, both as chemical feedstock and also as energy carrier for transportation. The annual world production of hydrogen amounts to some 50 million tonnes and the majority is produced using fossil fuels like natural gas, coal and naphtha. High temperature nuclear reactors (HTRs) represent a novel way to produce hydrogen at large scale with high efficiency and less carbon footprint. The aim of this master thesis has been to evaluate the feasibility of HTRs for hydrogen production by analyzing both the reactor concept and its potential to be used in certain hydrogen niche markets. The work covers the production, storage, distribution and use of hydrogen as a fuel for vehicles and aviation and as chemical feedstock for the oil refining and ammonia production industry. The study indicates that HTRs may be suitable for hydrogen production under certain conditions. However, the use of hydrogen as an energy carrier necessitates a widespread hydrogen infrastructure (e.g. pipe-lines, refuelling stations and large scale storage), which is associated with major energy losses. Both mentioned industries could benefit from nuclear-based hydrogen with less infrastructural changes, but the potential market is by far smaller than if hydrogen is used as an energy carrier. A maximum of about 60 HTRs of 600 MWth worldwide has been estimated for the ammonia production industry. The Swedish refineries are likely too small to utilize the HTR but in the larger refineries HTR might be applicable.

No description available.