Made available in DSpace on 2015-05-14T13:21:51Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3041446 bytes, checksum: ababcafc4806728e34bf8d0bd8ea021e (MD5) Previous issue date: 2010-09-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This study proposed a miniaturized flow-batch system for chemical analysis. The technique used microfabricated urethane-acrylate, a commercial polymer. The microsystem was evaluated and optimized by analysis of synthetic dye samples. Afterwards, it was employed for the determination of tannins in tea samples. The tannins are a group of polyphenols of significant relevance in the food industry and pharmaceuticals. The samples used were green and black tea, obtained from the local market. The determinations were performed by turbidimetric methods using copper (II) in an acetate medium, with photometric methods and ferrous tartrate as a reference. Miniaturization in urethane-acrylate implies low cost and low maintenance, rapid prototyping and includes the satisfactory physicochemical properties of polymer. These characteristics combined with the general advantages of miniaturization in analytical devices, such as high frequency analysis and low waste generation, make the system a great source in academic research. For analysis of tannins in tea samples, the system had precise and accurate results, and high speeds. This flow-batch microsystem was able to perform up to 300 tests per hour, for the photometric method of reference and up to 200 tests per hour for the turbidimetric method. Each analysis performed generated waste volumes lower than 70 μL. Data validation of statistical models obtained have proved very satisfactory and promising for new optical applications. / Neste trabalho de pesquisa foi proposto o uso da técnica de microfabricação em polímero comercial uretana-acrilato para a miniaturização de um sistema automático de análises químicas em fluxobatelada, o flow-batch. O microssistema desenvolvido foi avaliado e otimizado pela análise de amostras sintéticas de corantes. Posteriormente, o microssistema, foi empregado para a determinação de taninos, grupo de polifenóis de expressiva relevância industrial, em amostras de chá verde e preto, por dois métodos ópticos distintos, fotométrico e turbidimétrico. A técnica de microfabricação em uretana-acrilato se caracteriza pelos baixos custos de implementação e manutenção, satisfatórias propriedades físicoquímicas do polímero e a rápida prototipagem de sistemas microfluídicos. Tais características aliadas às vantagens inerentes da miniaturização de dispositivos analíticos, como a elevada frequência de análise e a baixa geração de resíduos, conferem a esse sistema de análise uma ótima fonte de pesquisa acadêmica. Para análise dos taninos em amostras de chá, o sistema apresentou resultados precisos e exatos, além de uma alta velocidade analítica para ambos os métodos ópticos, sendo capaz de executar até 300 análises por hora, no método fotométrico e 200 análises por hora pelo método turbidimétrico. Cada análise efetuada gerou resíduos cujos volumes foram inferiores a 70 μL. Os dados de validação estatística dos modelos obtidos se mostraram bastante satisfatórios e promissores para novas aplicações ópticas.

Submitted by (edna.saturno@ufrpe.br) on 2016-07-27T15:26:38Z No. of bitstreams: 1 Sonia Paula Alexandrino de Oliveira.pdf: 561366 bytes, checksum: c192a2b79e10a3f472b46ce8e1815d29 (MD5) / Made available in DSpace on 2016-07-27T15:26:38Z (GMT). No. of bitstreams: 1 Sonia Paula Alexandrino de Oliveira.pdf: 561366 bytes, checksum: c192a2b79e10a3f472b46ce8e1815d29 (MD5) Previous issue date: 2012-02-29 / Among the various toxic substances found in alcoholic beverages, especially in spirits, ethyl carbamate (EC), a recognized carcinogen of organic nature, has drawn great attention to food inspecting authorities and researchers. Taking into account various scientific studies showing that cachaça, the most consumed spirit in Brazil, has high levels of EC, the Brazilian Ministry of Agriculture, Livestock and Food Supply (MAPA) established an EC limit (150 μg.L-1) for the beverage in 2005 (which is coming into effect in June 2012), but other consumed spirits in Brazil, such as rums and whiskies, are not subjected to EC control by MAPA. Given the lack of information on the chemical profiles of rums and whiskies produced in Brazil, the objective of this study was to quantify congeners (volatile acids, aldehydes, esters, furfural, higher alcohols), EC and other contaminants (methanol, acrolein, sec-butanol, copper, lead and arsenic) in these beverages. Fifteen brands of rum and nine brands of whisky were sampled. All brands were low-priced (below US$20 per bottle) and recorded (licit). With the exception of two brands of rum, all brands complied with MAPA regulation for total congeners. With respect of EC, levels above 50 μg.L-1 (limit of quantification) were observed in one brand of whisky (86 μg.L-1) and three brands of rum (115, 340 e 278 μg.L-1). Therefore, the majority (83%) of sampled brands complied with the international EC limit for spirits (150 μg.L-1). It was also observed that the two brands of rum which exceeded the EC limit (126% and 85%) also presented relatively high levels of methanol. In general terms, the results indicate that distillation processes used in rum and whisky production in Brazil, notably column distillation and rectification, are suitable for controlling EC and other contaminants. Although rum and cachaça originate from the same raw material (sugar cane), EC levels in rum is comparatively lower. This observation is probably related to the distillation process (column distillation and rectification) or the physicochemical treatment by which the sugar cane juice is subjected (conversion into molasses) in rum production. / Dentre as várias substâncias tóxicas encontradas em bebidas alcoólicas, especialmente nas destiladas, o carbamato de etila (CE), um reconhecido carcinógeno de natureza orgânica, tem despertado grande atenção dos órgãos de fiscalização e pesquisadores. Em 2005, após constatação que a cachaça, a bebida alcoólica destilada mais consumida no Brasil, possuía elevado nível deste contaminante, o Ministério da Agricultura, Pecuária e Abastecimento (MAPA) estabeleceu uma tolerância de 150 μg de CE por litro de cachaça (a entrar em vigor em junho de 2012), porém outras bebidas destiladas de consumo popular, tais como runs e uísques produzidos no Brasil, ficaram livres deste controle. Assim, diante do desconhecimento do nível de CE, aliada a carência de informações sobre os perfis químicos de runs e uísques produzidos no Brasil, esta pesquisa teve como objetivo quantificar congêneres (acidez volátil, aldeídos, ésteres, furfural e alcoóis superiores), CE e outros contaminantes (metanol, acroleína, sec-butanol, cobre, chumbo e arsênio) nestas bebidas. Foram amostradas 15 marcas de rum e 9 marcas de uísque, todas do segmento de consumo popular (definidas com base no preço – até R$35,00 por unidade). Com exceção de duas marcas de rum, todas as demais estavam adequadas quanto aos limites estabelecidos pelo MAPA para o somatório de congêneres. Também foi observada adequação dos níveis de metanol, cobre, chumbo, arsênio e sec-butanol à legislação vigente. Quanto ao CE, foram verificados níveis acima de 50 μg.L-1 (limite de quantificação do método) em quatro marcas amostradas, uma de uísque (86 μg.L-1) e três de rum (115, 340 e 278 μg.L-1), portanto, a maioria (83%) apresentou adequação quanto ao nível internacionalmente tolerado para o contaminante em destilados (150 μg.L-1). No caso particular do CE em rum, observou-se que as duas marcas que ultrapassaram (126% e 85%) a citada tolerância também apresentaram níveis relativamente elevados de metanol. De um modo geral, os resultados indicam que os processos de destilação empregados na produção de runs e uísques no Brasil, notadamente a destilo-retificação, são adequados para controlar o nível de congêneres, CE e outros contaminantes. Este trabalho também mostrou que apesar do rum e da cachaça se originarem da mesma matéria-prima (cana-de-açúcar), o nível do CE no rum é comparativamente menor. Tal fato está provavelmente relacionado ao processo de destilação ou ao tratamento físico-químico pelo qual o caldo de cana é submetido (conversão em melaço) na produção do rum.

INTRODUÇÃO. Estudos epidemiológicos têm demonstrado que a exposição à poluição atmosférica está associada ao aumento de doenças cardiorrespiratórias. Trabalhos experimentais anteriores, utilizaram uretana para induzir a formação de nódulos pulmonares em camundongos e expor estes animais à poluição de \"mundo real\". Ou seja, os animais foram expostos a gases e partículas da mesma forma com que a população está exposta na cidade de São Paulo. Evidenciou-se então, o papel promotor e dose dependente da atmosfera poluída na progressão dos tumores de pulmão. Sabe-se que substâncias carcinogênicas como hidrocarbonetos policíclicos aromáticos (HPA), metais, ácidos graxos e aldeídos, estão presentes na fração particulada respirável da poluição (material particulado fino - MP 2,5), e a exposição prolongada a este último vem sendo considerada um risco para o desenvolvimento do câncer de pulmão. O objetivo deste estudo é verificar se a exposição crônica ao MP2,5 concentrado, a partir do ar ambiente da cidade de São Paulo, tem potencial carcinogênico. MÉTODOS. Foram utilizados 60 camundongos machos suíços (30g); e 60 AJ (20g), com quatro a seis semanas de vida. Os camundongos suíços foram pré-tratados com um carcinógeno completo, o ácido carbâmico (uretana-U), enquanto que os AJ receberam um carcinógeno iniciador 4-(methylnitrosamino)-1-(3-pyridil)-1-butanona (NNK), por serem pré-dispostos ao desenvolvimento de tumores de pulmão. Em seguida todos os animais foram expostos no Concentrador de Partículas Atmosféricas Harvard ao MP 2,5 diariamente, por 2 horas, durante quatro meses. Cada linhagem foi dividida em quatro grupos (n=15 cada): 2 controles com salina e carcinógeno (CsS e CsU ou CajS e CajNNK) e 2 expostos com salina e carcinógeno (EsS e EsU ou EajS e EajNNK). Foi realizada a análise histopatológica dos pulmões, a contagem e classificação das lesões pulmonares encontradas. Foi feito estudo imunoistoquimico para p53 e PCNA. RESULTADOS. Os animais dos grupos expostos, em ambas as linhagens, apresentaram maior número de lesões neoplásicas. As médias de lesões (nódulos e hiperplasia) obtidas foram: CsU: 1,07( DP+ 1,54), CsSl: 0( DP+ 0), EsU: 2,57 ( DP+ 2,77) e EsS: 0,40 ( DP+ 1,12), com p < 0,001; CajNNK: 4,94( DP+ 3,54), CajS: 0,15( DP+ 0,37), EajNNK: 9,14 ( DP+ 7,70) e EajS:0,80 ( DP+ 1,93), com p<0,001. Não houve alterações para o p53 em ambas as linhagens e, apenas os grupos AJ controle e exposto NNK apresentaram diferença para o PCNA. CONCLUSÃO. A exposição crônica ao MP 2,5 proveniente da poluição atmosférica da cidade de São Paulo tem potencial para promover tumores em camundongos de duas linhagens diferentes, com ou sem o pré-tratamento por carcinógenos / INTRODUCTION. Epidemiological studies have shown that exposure to air pollution is associated with increased cardiorespiratory diseases. Previous experimental studies, we used urethane to induce lung nodule formation in mice and these animals exposed to pollution from \"real world.\" In these studies, animals were exposed to gases and particles in the same way that the population is exposed in the city of São Paulo. It was evident then, the role of promoter and dose dependent polluted atmosphere in the progression of lung tumors. It is known that carcinogens such as polycyclic aromatic hydrocarbons (PAHs), metals, aldehydes and fatty acids, are present in the respirable fraction particulate pollution (fine particulate matter - PM2.5), and prolonged exposure to the latter has been considered a risk factor for the development of lung cancer. The objective of this study is to verify whether chronic exposure to PM 2.5 concentration from the air of the city of São Paulo, has carcinogenic potential. METHODS. A total of 60 male Swiss mice (30 g) and 60 AJ (20g), with four to six weeks of life. The Swiss mice were pretreated with a carcinogen completed, the carbamic acid (urethane-U), while AJ received a carcinogen primer 4 - (methylnitrosamino) -1 - (3-pyridil)-1-butanone (NNK) as being predisposed to developing lung tumors. Then all the animals were exposed to atmospheric Harvard Particle Concentrator to PM 2.5 daily for two hours for four months. Each strain was divided into four groups (n = 15 each): 2 with saline controls and carcinogen (CsS and CsU or CajS and CajNNK) and 2 exposed to saline and carcinogen (EsS and EsS or EajS and EajNNK). After the exposure time, the animals were anesthetized and euthanized. The lungs were fixed, processed histologically and imunohistochemistry was performed on slides with tumor presence of antibodies to p53 and PCNA. Later, in histopathology of pulmonary nodules made counting and classification of lesions found. RESULTS. The animals exposed groups in both strains showed a high percentage of neoplastic lesions. Mean lesions (nodules and hyperplasia) were obtained: CsU: 1.07 (SD + 1.54), CsS: 0 (DP + 0), EsU: 2.57 (SD + 2.77) and EsS: 0.40 ( + SD 1.12), p < 0.001; CajNNK: 4.94 (SD + 3.54), CajS: 0.15 (SD + 0.37), EajNNK: 9.14 (SD + 7.70) and EajS: 0 , 80 (SD + 1.93), with p < 0.001. There were no changes to the p53 in both strains, and only groups A / J control and exposed to NNK differ PCNA. CONCLUSION. The chronic exposure to PM 2.5 air pollution from the city of São Paulo has the potential to promote tumors in mice of two different strains with or without pretreatment by carcinogens

Sous l’impact des agressions environnementales (lumière, température, eau …), les peintures de carrosseries automobiles voient leurs propriétés (couleur, brillant, …) se dégrader. L’amélioration de leur tenue dans le temps est l’un des enjeux importants auxquels sont confrontés les constructeurs automobiles. La compréhension des phénomènes mis en jeu nécessite un travail de recherche important. Les objectifs de cette thèse ont été d’étudier les mécanismes de photovieillissement de polymères tridimensionnels (acrylique-mélamine et acrylique-uréthane) depuis l’échelle moléculaire (structure chimique du polymère) jusqu’à l’échelle macroscopique (propriétés fonctionnelles du matériau). L’étude de l’influence de chacune des contraintes (lumière, eau, …) indépendamment les unes des autres a permis de comprendre le comportement du matériau dans les conditions naturelles où toutes ces contraintes se superposent. Nous avons montré que le photovieillissement des vernis mettait en jeu la dégradation des fonctions chimiques formées lors de l’étape de réticulation du vernis, entraînant une densification du réseau au cours du vieillissement et menant à l’apparition d’un faïençage lorsqu’un seuil de contraintes internes était atteint. On a également montré qu’il existait une relation étroite entre le mécanisme chimique de dégradation, l’obtention d’un palier de dureté et l’apparition du faïençage. Sur la base de comparaisons entre vieillissement naturel et vieillissement artificiel accéléré, des facteurs d’accélération ont été calculés, permettant de prévoir à partir d’une irradiation en conditions de vieillissement artificiel accéléré, la durée de vie des vernis. / It is well known that under environmental stresses impact (light, temperature,water, ...), car paints properties (color, gloss, ...) deteriorate. Improving clearcoats performance over time is one of the most important issues that car manufacturers have to solve. This necessitates an important research activity. The main objectives of this thesis were to study the mechanisms of photoageing of crosslinked polymers (acrylic-melamine and acrylic-urethane) from the molecular (chemical structure of the polymer) to the macroscopic scale (functional properties of the material). The study of the influence of individual stress (light,water, ...) independently each from other has allowed us to understand the behavior of the material under natural conditions where all these stresses overlap. We have demonstrated that the photoageing of clearcoats leads to the degradation of the chemical function formed along with the crosslinking process. We have observed that this results in a significant network densification, leading to the appearance of cracking when a threshold of internal stresses is reached. We have also demonstrated a close relationship between the degradation mechanism, the hardness values and the time required for cracks appearance. Based on comparisons between natural and artificial ageing, acceleration factors were calculated to predict clearcoats service life from an accelerated ageing.

<p>U radu su prvi put za proveru teorija nastajanja i gumolike elastičnosti polimernih mreža primenjeni modelni poliuretanski sistemi čiji su čvorovi veoma stabilni izocijanurat(heksahidro-1,3,5-triazin- 2,4,6-trion) prstenovi. Rad obuhvata: (1) Sintetezu nekoliko serija homogenih poli(uretan-izocijanuratnih) mreža, na bazi 2.4-TDI i poli(oksipropilen)diola, dvoetapnim postupkom u masi, tj. ciklotrimerizacijom teleheličnih diizocijanata uz katalizator Polycat 41. (2) Sintezu manje savr&scaron;enih mreža sa nekom definisanom koncentracijom visećih lanaca koja je postignuta uvodenjem monoola dietilenglikol- monometiletra u toku pripreme prepolimera. (3) Odredivanje povoljnih reakcionih uslove svih etapa sinteze uz primenu i modifikaciju postojećih analitičkih postupaka za karakterizaciju svojstava reakcionih komponenti i praćenja reakcija umrežavanja. (4) Procenu mogućih bočnih reakcija u toku nastajanja mreža jer one mogu značajno uticati na raspodelu različitih fragmenata u mrežama praćenjem koncentracija reakcionih proizvoda kod modelnih reakcija u rastvoru uz isti diol i isti katalizator i odgovarajuće mono-funkcionalne izocijanatne komponente. (5) Karakterizaciju svojstava i strukturnih parametara modelnih mreža i to primenom postupaka ekstrakcije i bubrenja, diferencijalne skanirajuće kalorimetrije, fotoelastičnih merenja, dinamičko-mehaničke spektroskopije i merenja napon-istezanje. Izborom nominalne Mn diola od 400 do 4000 postigne gustina umreženja 0.1x10^-4mol/cm³ do 10x10^-4mol/cm³ sa rasponom temperatura staklastog prelaza od -60&deg;C do +30&deg;C. Za procenu strukturnih parametara mreža primenjena je teorija granajućih procesa sa kaskadnom zamenom za slučaj nastajanja mreža ciklotrimerizacijom i dvoetapni postupak. U zavisnosti od konverzije NCO grupa u mrežama izračunate su masa po monomernoj jedinici, maseni udeo, broj po monomernoj jedinici, koncentracija po jedinici zapremine, Mn, Mw, Mz i Mw/Mn kako za elastično aktivne, osnovne i viseće lance tako i zamolekule sola. Ključni ekspehmentalni podaci koji su kori&scaron;ćeni za proveru teorija nastajanja bio sadržaj gela dobijen vi&scaron;estrukim ekstrakcijama, a za teorije gumolike elastičnosti ravnotežni modul dobijen iz fotoelastičnih merenja. Provera teorija gumolike elastičnosti se zasnivala se u nalaženje vrednosti pred- faktora 3 (tzv. faktora pamćenja) u jednačini koja daje vezu ravnotežnog modula elastičnosti i koncentracije elastično aktivnih lanaca mreže koji ukazuje na način fluktuacije cvorova mreže. Fotoelastična merenja su omogućila da se preko njih parameter pred-faktor 3 proceni pri malim deformacijama. Potvrden je koncept stvarnih mreža sa delimično potisnutim fluktuacijama čvorova uz aditivni doprinos zapletenosti lanaca modulu elastičnosti prema Langley-Graesley konceptu zarobljenih prepletaja.</p> / <p>In this thesis polymer network formation theories and rubber elasticity of polymer networks on model polyurethane systems having as a junction very stable isocyanurate(hexahidro-1,3,5-tгiazin-2,4,6- trion) rings are for the first time investigated. The work contains: (1) Synthesis of homogenious series of several poly(urethane-isocyanurate) networks based on poly(oxypropylene)diol and 2.4-TDI by two stages procedures in bulk i.e. cyclotrimerization of telechelic diisoicyanates with Polycat 41 as catalyst. (2) Synthesis of less perfect networks with some concentration of dangling chains obtained by introduction of monofunctional component diethyleneglycolmonomethylether during prepolymer formation. (3) Determination of optimal reaction conditions for both stages of the synthesis. (4) Estimation of possible side reaction during network formation because of theirs important influence on nework fragment distribution. (5) Caracterization of networks structure and properties by swelling and multiply extraction, differential scanning calorimetry, photoelastical measurements, dynamic-mechanical spectroscopy and stress-strain measurements. By using the different Mn of diols (400 - 4000) the network density from<br />0.1x10^-4mol/cm³ to 10x10^-4mol/cm³ and glass transition temperatures from -60&deg;C to +30&deg;C was achieved. For network structure determinations the theory of branching processes with cascade substitution was used. Mass per monomer unit, mass fraction, number per monomer unit, concentration per unit volume, Mn, Mw, Mz and Mw/Mn for elastically active network chains, backbone chains, dangling chains and sol molecules In the dependence on NCO groups conversion are calculated. Crucial experimental data for examination of network formation theories was the gel content and for rubber<br />elasticity theories the equilibrium modulus received from photoelastical measurement. The estimation of rubber elasticity theories was based on the analysis of the front factor 3 in the equation which gives the relation between the equilibrium modulus and concentration of elastically active network chains. It is estimated the additive contribution of chain entanglements to the equilibrium modulus, especially in the case of high networks density according to Langley-Graesley theory of trapped entanglements.</p>

Des polyacides lactiques hydroxy téléchélique de masses molaires variées ont été synthétisés par polymérisation par ouverture de cycle du LLA en présence de 1,4 -butane diol. Des polyhydroxybutyrate hydroxy téléchéliques ont été préparés transesterification du PHB et du 1,4-butanediol catalysée par l'acide p-toluène sulfonique .Ces oligomères ont été utilisés pour préparer des polyesters amides fonctionnalisés acrylates ou mercaptans. Dans une approche parallèle, du PCL multi acrylate a été préparé avec succès par copolymérisation par ouverture de cycle de méthacrylate de glycidyle avec du caprolactone. Des copolymères (GMA -co- CL) ayant des masses molaire et de la fonctionnalité variables, ont été préparés en modifiant les paramètres de la réaction tels que le catalyseur, la nature du co-amorceur et le rapport des stœchiométriques des différents réactifs. Les polymères multi acrylates ont été copolymérisés principalement avec l'HEMA sous irradiation UV pour obtenir des réseaux PLA, PHB et PCL segmentés. Les mécanismes de dégradation de ces réseaux ont été étudiés en examinant particulièrement les décompositions des liaisons uréthanes et esters. Des dépolymérisations du PHEMA ont été détectées avec TGA -FTIR à plus haute température (450°C). Pour les réseaux à base de PCL, les propriétés thermo -mécaniques ont été étudiées. Le résultat montre que les phases riches en PCL ont une bonne compatibilité avec le poly HEMA. Les modules caoutchoutiques et l’étendue des températures des zones d’amortissement peuvent être contrôlées en fonction des paramètres réactionnels. Les Polymères multifonctionnels Thiols du PCL, PHA et PLA ont été utilisés pour faire croître des chaines méthacrylates et construire des polymères de type étoile / Hydroxyl telechelic polylactic acids of various molecular weights were synthesized by ring opening polymerization in the presence of LLA and 1,4-butanediol. Telechelic hydroxy polyhydroxybutyrate were prepared transesterification of PHB and 1,4- butanediol catalyzed by p- toluene sulfonic acid. These oligomers were used to prepare polyesteramides functionalised acrylates or mercaptans. In a parallel approach, the PCL multi acrylate was successfully prepared by ring-opening copolymerization of glycidyl methacrylate with caprolactone. Copolymers (GMA-co-CL) with variable molar masses and functionality were prepared by changing the reaction parameters such as catalyst, the nature of the co-initiator and the ratio of different stoichiometric reagents. Multi-acrylated polymers were copolymerized with HEMA under UV irradiation to obtain PLA, PHB and PCL segmented networks. Degradation mechanisms of these networks have been studied by examining particular decomposition of urethane bonds and esters. Depolymerization of the PHEMA was detected with TGA -FTIR at higher temperature (450°C). For PCL based networks, the thermo- mechanical properties were studied. The result shows that the PCL-rich phases have good compatibility with poly HEMA. The rubber and the working temperature range of the damping zones modules can be controlled as a function of reaction parameters. Multi mercapto functionalized polymers with PCL, PLA and PHA segments were used to grow methacrylate polymer chains and build star type

No description available.

A growing interest for Cannabidiol (CBD), a component of Cannabis Sativa, has occurred over the past years. The medical potential of the component is yet to be better characterized, as its effects on sleep, and in particular memory, are to date not well understood or consistently characterized. This master thesis project focuses on analysing the effect of CBD on an anaesthesia-induced sleep-like state in rats, and its effects on the hippocampal sharp-wave-ripples, which have been shown to be associated with memory replay during sleep, and hence system consolidation. The hippocampus and prefrontal cortex, the two structures involved in memory consolidation, were recorded in 19 rats, split in two groups (CBD and vehicle). From these recordings, an automated sleep scorer using principal component analysis was developed to obtain the animals’ hypnograms, which were analysed to study sleep-like structure. From the recordings of the hippocampal pyramidal layer, and an additionnal layer deeper under it, respectively ripples and sharp waves were detected in all animals, and characterized for each group. We observed and demonstrated that CBD changes the sleep-like structure by shortening both REM and NREM bouts, resulting in an increase in transitions between both states. Additionally, we observed that, although ripples are not significantly different between both groups, sharp waves tend to be smaller among CBD animals. Lastly we noticed that both sharp wave and ripple activity, after increasing upon transition to NREM, decreases as the bout last. This finding suggests that vehicle animals, who have longer bouts and less transitions, would display less sharp wave and ripple activity, although we found no significant difference in the amount of both brain events. This paradox suggests that there is still more to characterize in order to understand if CBD enhances or not memory consolidation. In sum, CBD changes anaesthesia-induced sleep by shortening the duration of both NREM and REM bouts, resulting in an increase in transitions between both state. As for sleep events, sharp waves appeared shorter among CBD animals, although the same difference was not observed for ripples. Finally, sharp wave and ripple activity appear to peak upon transition from REM to NREM sleep, and decreases as the NREM bout lasts longer, however, no effect of CBD on this observation was highlighted.

Made available in DSpace on 2016-01-26T12:51:52Z (GMT). No. of bitstreams: 1 paulo saad_tese.pdf: 455472 bytes, checksum: 76fed03b80932ea6f964693d4c8d92cf (MD5) Previous issue date: 2006-06-19 / Cigarettes accounts for the death of millions of people a year worldwide, directly related to lung cancer. Some studies have shown that larger plasmatic indexes of beta-carotene or a great ingestion of foods rich in carotenoids diminish the risk of developing this neoplasia. On the other hand, studies suggest that the smokers' lung can alter the metabolism of beta-carotene, that is, producing greater risk of cell alterations and neoplasias. It is probable that the alpha-tocopherol has beneficial effect on this association. Objective: To evaluate the participation of beta-carotene and alpha-tocopherol in the development of lung cancer induced by urethane and its relationship with cigarette exposition. Material and Method: Balb C mice were divided into 10 groups: G1(cigarette), G2 (cigarette and urethane), G3 (only urethane), G4, G5 and G6 (cigarette, urethane and beta-carotene to 0.25, 0.05 and 0.005%, respectively), G8 (urethane and beta-carotene to 0.25%), G7, G10 and G11 (cigarette, urethane and beta-carotene to 0.25 and alpha-tocopherol 0.25; 0.05 and 0.005%, respectively).The exposition to the cigarette was for 10 minutes, twice a day, 5 days a week, during 16 weeks. For induction of tumors, urethane was administered intraperitonealy, in the dose of 3.0mg/Kg. Nodules and hyperplasias were quantified; morphometric analyses of the nodules were performed. Kruskal-Wallis and of Mann-Whitney tests were used for statistical analysis. Results: Group G3 presented greater number of nodules (P=0.001), smaller stromal fraction (P=0.011) and greater sum of the tumor area (P=0.047) compared to group G2. Group G8 showed smaller number of nodules (P=0.013) and hyperplasias (P=0.05) compared to group G3. Both smaller doses of beta-carotene (G5 and G6) were statistically similar, although with smaller number of nodules when compared to group G4 (P=0.04). Group G4 presented smaller number of hyperplasias than G8, however, the number of nodules did not alter (P=0.045%). Stromal fraction of groups G3 and G4 was similar, although smaller than G2 and G5 (P=0.011). According to the alpha-tocopherol, the stromal fraction of group G7 was greater than the one of the groups G2, G3, G4 and G10 (P=0.011). The 0.25%-beta-carotene diet increased the area of the nodules, demonstrated by the largest area (P=0.03), smaller area (P=0.03), sum of the areas (P=0.018) and average of the areas (P=0.006) in group G4 when compared to G2. Conclusion: According to these results, it was concluded that passive tobacco can be a protecting factor in the evolution of tumors induced by urethane in mice, however, there is no evidence that this could be dose-dependent. The supplementation of beta-carotene in 0.25%-dose can also be a protecting factor, however, associated to passive tobacco it has smaller effect than in lower doses (0.05 and 0.005%). The exposition to cigarette smoke does not alter the number of nodules induced by urethane in mice when in the presence of 0.25%-beta-carotene diet; however the hyperplasia number with the presence of the cigarette diminished. The association of the alpha-tocopherol to the 0.25%- beta-carotene and the passive tobacco produces a protecting factor, mainly in the dose of 0.25%. / O hábito de fumar cigarros é responsável pela morte de milhões de pessoas por ano em todo o mundo, estando diretamente relacionado ao câncer de pulmão. Estudos demonstraram que maiores índices plasmáticos de beta-caroteno ou a grande ingestão de alimentos ricos em carotenóides diminuem o risco de desenvolver esta neoplasia. Por outro lado, existem estudos que sugerem que o pulmão de fumantes pode alterar o metabolismo do beta-caroteno, gerando maior risco de alterações celulares e neoplasias. É provável que o alfa-tocoferol tenha efeito benéfico sobre esta associação. Objetivo: Avaliar a participação do beta caroteno e do alfa-tocoferol no desenvolvimento de câncer de pulmão induzido por uretana e sua relação com a exposição ao cigarro. Material e Método: Camundongos Balb C foram divididos em 10 grupos: G1(cigarro), G2(cigarro e uretana), G3 (uretana), G4, G5 e G6 (cigarro, uretana e beta-caroteno a 0,25; 0,05 e 0,005% respectivamente), G8 (uretana e Beta-caroteno a 0,25%), G7, G10 e G11 (cigarro, uretana e beta-caroteno a 0,25 e alfa-tocoferol a 0,25; 0,05 e 0,005% respectivamente). A exposição ao cigarro ocorreu durante 10 minutos, 2 vezes por dia, 5 dias por semana, por 16 semanas. Para a indução de tumores, foi administrada uretana por via intraperitoneal na dose de 3,0mg/Kg. Foram quantificados nódulos e hiperplasias, realizada análise morfométrica dos nódulos e submetidos aos testes de Kruskal-Wallis e de Mann-Whitney para análise estatística. Resultados: O grupo G3 apresentou maior número de nódulos (P=0,001), menor fração estromal (P=0,011) e maior soma da área de tumor (P=0,047) comparado ao grupo G2. O grupo G8, mostrou-se com menor número de nódulos (P=0,013) e hiperplasias (P=0,05) comparados ao grupo G3. As duas doses menores de beta-caroteno (G5 e G6) se mostraram estatisticamente semelhantes, porém com menor número de nódulos quando comparados ao grupo G4 (P=0,04). O grupo G4 apresentou menor número de hiperplasias que G8, porém o número de nódulos não se alterou (P=0,045). A fração estromal dos grupos G3 e G4 foram semelhantes, porém menores que G2 e G5 (P=0,011). Quanto ao alfa-tocoferol, a fração estromal do grupo G7 foi maior que a dos grupos G2, G3, G4 e G10 (P=0,011). A dieta com beta-caroteno a 0,25% aumentou a área dos nódulos, demonstrada pela maior área (P=0,03), menor área (P=0,03), soma das áreas (P=0,018) e média das áreas (P=0,006) no grupo G4 comparada com o grupo G2. Conclusão: Com estes resultados, concluiu-se que na evolução de tumores induzidos por uretana em camundongos o fumo passivo se comporta como um fator protetor, porém não há evidência de que seja dose-dependente. A suplementação de beta-caroteno na dose de 0,25% também age como protetor, porém associada ao fumo passivo tem efeito menor do que em doses mais baixas (0,05 e 0,005%). A exposição à fumaça do cigarro não altera o número de nódulos quando na presença de dieta com beta-caroteno a 0,25%, porém o número de hiperplasias com a presença do cigarro diminui. A associação do alfa-tocoferol ao beta-caroteno 0,25% e ao fumo passivo gera um fator protetor, principalmente na dose 0,25%.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Entre os polímeros considerados promissores para a remoção seletiva de CO2, destacam-se aqueles que contêm os grupos glicol etilênico (EG). Nesta dissertação, foram obtidos filmes a partir de dispersões aquosas de poliuretano (PU), sintetizadas em trabalho anterior, à base de poli(glicol propilênico) (PPG), copolímero em bloco à base de poli(glicol etilênico) (PEG) e PPG (EG-b-PG), ácido dimetilolpropiônico (DMPA), diisocianato de isoforona (IPDI) e etilenodiamina (EDA). PPG, EG-b-PG e DMPA formaram as regiões flexíveis nas proporções de: PPG 100% e 0% EG-b-PG, PPG 75% e 25% EG-b-PG, PPG 50% e 50% EG-b-PG e PPG 25% e 75% EG-b-PG em termos de equivalentes-gramas. A influência da quantidade dos segmentos de PEG foi avaliada por ensaios de permeação com os gases CO2, CH4 e N2. Os filmes obtidos das dispersões foram caracterizados por espectrometria de infravermelho com transformadas de Fourier (FTIR), análise termogravimétrica (TGA), difração de raios x (DRX) e espalhamento de raios X a baixo ângulo (SAXS). Espectros de FTIR mostraram que os segmentos de EG influenciaram a frequência da banda de carbonila. Curvas de perda de massa (TG) mostraram perfis semelhantes de degradação, enquanto que as curvas derivadas apresentaram diferenças. DRX e SAXS mostraram que os segmentos de PEG promoveram uma maior ordenação na estrutura da membrana. Testes de permeação de gases mostraram que o aumento do teor de PEG aumentou o valor da permeabilidade para o CO2, indicando que os segmentos de PEG interagiram favoravelmente com este gás. Em relação ao CH4 e N2, houve uma diminuição na permeabilidade quando comparados com os valores encontrados para o CO2, sendo atribuído a perda de mobilidade segmental. Em termos de seletividade, para o par CO2/CH4 foi obtido um valor médio de 61,7 para a membrana contendo o maior teor de PEG, e o par CO2/N2 um valor médio de 121,5, sendo superior aos valores encontrados na literatura, tornando o material promissor / Among the polymers considered promising for the selective removal of CO2 from natural gas, those containing ethylene glycol groups (EG) are the most distinguished. In this study cast films were obtained from aqueous dispersions of polyurethane (PU), synthesized in a previous work with poly (propylene glycol) (PPG), block copolymer based on poly(ethylene glycol) (PEG) and PPG, dimethylolpropionic acid (DMPA), isophorone diisocyanate (IPDI) and ethylenediamine (EDA). Segments of PPG, EG-b-PG and DMPA formed the flexible domains in the proportions of: PPG 100% and 0% EG-b-PG, PPG 75% and 25% EG-b-PG, PPG 50% and 50% EG-b-PG and PPG 25% and 75% EG-b-PG, in terms of equivalent-grams. The influence of the amount of PEG segments in permeation properties of CO2, CH4 and N2 was verified by permeability essays. The membranes were obtained as cast films from the dispersions and was characterized by infrared spectrometry (FTIR), termogravimetric analysis (TGA), X ray diffractometry (XRD) and small angle X ray scattering (SAXS). FTIR spectra showed that PEG segments influenced carbonyl band frequency. Loss of mass curves with temperature (TG) showed similar profiles of degradation, whereas DTG curves presented more stages. PEG segments conferred higher thermal stability for the materials. XRD and SAXS analysis showed that PEG promoted ordination to the membranes. In gas permeation tests, it was verified that the increase in copolymer amount increased permeability value for CO2, being attributed to the fact that the segments of poly(ethylene glycol) interacted favorably with this gas. In relation to CH4 and N2, there was a significant decrease in permeability when compared to the values found for CO2, being assigned to a loss of segmental mobility with increasing content of EG. In terms of selectivity, the pair CO2/CH4 had a mean value of 61,7 for the membrane containing the highest amount of EG groups, and the pair CO2/N2 produced a mean value of 121,5 for the same one, being superior than those found in the literature, making a promising material