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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Óleos essenciais para controle da podridão mole em couve-chinesa

GUERRA, Myrzânia de Lira 26 July 2011 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-22T15:55:30Z No. of bitstreams: 1 Myrzania de Lira Guerra.pdf: 865300 bytes, checksum: 159f62ad074b37facb2aca234031d937 (MD5) / Made available in DSpace on 2017-03-22T15:55:30Z (GMT). No. of bitstreams: 1 Myrzania de Lira Guerra.pdf: 865300 bytes, checksum: 159f62ad074b37facb2aca234031d937 (MD5) Previous issue date: 2011-07-26 / Chinese cabbage (Brassica pekinensis L.) is very important in the Brazilian horticulture due to its nutritional value and increasing yielding. In the Zona da Mata and Agreste of Pernambuco State, Brazil, this vegetable is intensely cultivated in the conventional system although its production is limited by several factors including the soft rot disease. It was evaluated the action of essential oils in controlling soft rot in Chinese cabbage and their influence in colorimetry and physicochemical characteristics of this vegetable. Preliminary fitotoxicity tests selected 11 oils. In the greenhouse, plants of cv. Natsume were sprayed with the oils of bergamot, lemon grass, copaiba, eucalyptus citriodora, eucalyptus globulus, fennel, ginger, mint, sweet orange, lemon and clary sage (0.5%) and the antibiotic Mycoshield® (3 g L-1), and inoculated with P. carotovorum subsp. carotovorum (Pcc-c) after 72 h. The disease severity was evaluated every six hours until 48 h, and the final severity (SEV) and area under the disease progress curve (AUDPC) were determined. The 11 oils and Mycoshield® reduced similarly SEV and AUDPreduced SEV in 53.1 and 38.8% and AUDPC in 37.0 and 27.5%, respectively. The oils of bergamot, copaiba, eucalyptus citriodora, mint and sweet orange were selected for further studies and tested for stability of the effectiveness of disease control in relation to three strains of Pcc. The interaction oils x strains was not significant (P≤0.05). The five oils reduced the SEV and AUDPC without differences between themselves or from Mycoshield®, except for copaiba oil that was less effective than the antibiotic in reducing the AUDPC. In the in vitro tests, filter paper discs were soaked in those five oils (0.5%) and Mycoshield® and deposited on culture medium containing Pcc-c. The pathogen was inhibited in vitro only by Mycoshield®. The technique of overlapping plates was used for detection of antibacterial activity of volatile substances at different pHs. Pcc-c growth was inhibited only by the oils of mint and bergamot at pH 7.0, and by the oil of copaiba at pH 8.0. The colorimetry of Chinese cabbage leaves, the ascorbic acid content and the pH of the plants treated with those five oils have not changed compared to the control without Pcc-c. The acidity was elevated by mint oil and total soluble solids (˚Brix) by the oils of sweet orange, eucalyptus citriodora and bergamot. / A couve-chinesa (Brassica pekinensis L.) destaca-se na olericultura brasileira pelo valor nutricional e aumento da produtividade. Nas regiões da Zona da Mata e do Agreste Pernambucano esta hortaliça é intensamente cultivada no sistema convencional tendo sua produção limitada entre outros fatores pela ocorrência da podridão mole. Avaliou-se a ação de óleos essenciais no controle da podridão mole em couve-chinesa e sua influência na colorimetria e características físico-químicas da hortaliça. Em testes preliminares de fitotoxidez foram selecionados 11 óleos. Em casa de vegetação, plantas da cv. Natsume foram pulverizadas com os óleos de bergamota, capim limão, copaíba, eucalipto citriodora, eucalipto globulus, funcho de erva-doce, gengibre, hortelã, laranja doce, limão e sálvia esclaréia (0,5%) e o antibiótico agrícola Mycoshield® (3g L-1), sendo inoculadas com Pectobacterium carotovorum subsp. carotovorum (Pcc-c) após 72 h. Avaliou-se a severidade da doença a cada seis horas até 48 h, determinando-se a severidade final (SEV) e área abaixo da curva de progresso da doença (AACPD). Os 11 óleos e o Mycoshield® reduziram similarmente a SEV e a AACPD em relação à testemunha. O óleo de hortelã e o Mycoshield® reduziram a SEV em 53,1 e 38,8% e a AACPD em 37,0 e 27,5%, respectivamente. Os óleos de bergamota, copaíba, eucalipto citriodora, hortelã e laranja doce foram selecionados para a continuidade dos estudos e testados quanto à estabilidade da eficácia de controle da doença em relação a três isolados de Pcc. A interação óleos x isolados não foi significativa (P≤0,05). Os cinco óleos reduziram a SEV e AACPD sem diferirem entre si ou do Mycoshield® exceto o óleo de copaíba que se mostrou menos eficiente do que o antibiótico na redução da AACPD. Nos testes in vitro, discos de papel de filtro foram embebidos nos cinco óleos (0,5%) e Mycoshield® e depositados sobre meio de cultura contendo Pcc-c. O patógeno foi inibido in vitro apenas pelo Mycoshield®. Para detecção da atividade antibacteriana das substâncias voláteis em diferentes pHs foi utilizada a técnica da placa sobreposta. O crescimento de Pcc-c foi inibido apenas pelos óleos de hortelã e bergamota no pH 7,0, e pelo óleo de copaíba no pH 8,0. A colorimetria das folhas da couve-chinesa, o teor de ácido ascórbico e o pH das plantas tratadas com os cinco óleos não foram alterados, considerando a testemunha sem Pcc-c. A acidez titulável foi elevada pelo óleo de hortelã e o ˚Brix pelos óleos de laranja doce, eucalipto citriodora e bergamota.
72

Características da neo formação dos tecidos moles periimplantares e periodontais após excisão cirúrgica de margem / Characterization of soft tissue neo formation around implants and teeth after margin surgical excision

Flávia Sukekava 10 September 2008 (has links)
O presente estudo descreve as características da cicatrização de tecido mole ao redor de dentes e implantes, em 5 cães beagle, após remoção cirúrgica. Os terceiros e quartos pré-molares inferiores bilateralmente foram extraídos. Três meses após, 2 implantes de titânio Osseospeed foram instalados em cada quadrante inferior, juntamente com a instalação imediata do conector na região dos pré-molares extraídos previamente. Três meses após a instalação dos implantes, quatro áreas contendo um implante e um dente foram determinadas e identificadas em cada cão. Uma área foi aleatoriamente escolhida em cada animal para receber a cirurgia ressectiva na face vestibular do dente e do implante. Na face lingual não foi executado qualquer procedimento ficando esta face como lado controle. As 3 áreas remanescentes foram tratadas de maneira idêntica e os animais foram ortotanasiados e forneceram biópsias representando os seguintes intervalos de cicatrização 1, 2, 4 e 12 semanas. As biópsias foram preparadas para análise histological e morfométrica. Foi observado que em 12 semanas a altura da mucosa periimplantar e da gengiva foram similares ao lado controle. Além disso, a análise morfométrica demonstrou que no intervalo 12 semanas o volume de feixes de fibras colágenas, fibroblastos, estruturas vasculares e tecido residual não foi similar entre o grupo de implantes comparando grupo teste com grupo controle. O presente experimento demonstrou que a cicatrização do tecido mole ao redor de implantes parece ser mais lenta que ao redor de dentes. / The current presentation will describe a study in the dog features characteristic of soft tissue healing after ressective surgery at teeth and implants. Five beagle dogs were used. In both quadrants of the mandible, the third and fourth premolars were extracted. Three months later, two titanium fixtures Osseospeed were installed and abutment connection performed in each mandibular quadrant at the premolar region of the edentulous ridge. Following additional 3 months of healing, four regions containing each implant and an adjacent tooth were identified in each dog. One region was randomly selected and soft tissue ressective surgery was performed at the buccal aspect. The lingual soft tissues were not included in the experimental surgical procedure and were regarded as control sites. The remaining three regions were treated in an identical manner and the dogs sacrificed to provide biopsies representing healing intervals of 1, 2, 4 and 12 weeks. The biopsies were prepared for histological and morphological analyses. It was observed that at the 12-weeek interval the height of the soft tissue both at the gingival and implant mucosa was similar to the one at the control site. Furthermore, the morphometric analyses demonstrated that the 12-week interval the volume of collagen fibers, fibroblasts, vessels and residual tissue in the healing tissues was not similar between the gingival and periimplant mucosa also differed from the control sites regarding the vascular content. The present experiment demonstrated that soft tissue healing around implants seems to be slower than around tooth.
73

The life history of Damaraland mole-rats, Fukomys damarensis : growth, ageing and behaviour

Thorley, Jack January 2018 (has links)
The social mole-rats have often been typecast as extreme examples of mammalian sociality. With their pronounced reproductive skew, status-related contrasts in lifespan and morphology, and the suggestion of a division of labour amongst helpers, mole-rat societies have repeatedly been likened to the structurally complex societies of some eusocial insects. However, because few studies of mole-rats have quantified individual variation in growth and behaviour across long periods of development, it has remained unclear the extent to which mole-rat societies, and the features of individuals within them, should be considered unique amongst social vertebrates. In this thesis, I examine life history variation in Damaraland mole-rats Fukomys damarensis from three perspectives- growth, behaviour, and ageing- to explore how individual developmental trajectories contribute to, and are influenced by, the structure of mole-rat societies. First, I use a large longitudinal dataset to test for the presence of behavioural specialisation in non-breeding mole-rat helpers. I find no indication of individual specialisation in cooperative activities. Instead, individual differences in helping behaviour are largely the result of age-related changes in the extent to which individuals commit to all forms of helping (Chapter 3); refuting the notion of helper castes. I then focus on the variation in growth across non-breeders, developing a novel biphasic model to accurately quantify sex differences in growth and explore the influence of social effects on growth trajectories (Chapter 4). Despite the proposition of intense intrasexual competition in mole-rat societies, there was no clear signature of sex-specific competition on helper growth trajectories. A more conspicuous form of socially-mediated growth in mole-rats is the secondary growth spurt displayed by females that have acquired the dominant breeding position, causing them to become larger and more elongated. By experimentally controlling reproduction in age-matched siblings, I show that rather than being stimulated by the removal from reproductive suppression, this adaptive morphological divergence is achieved through a lengthening of the lumbar vertebrae when breeding is commenced (Chapter 5). With contrasts in size and shape following the acquisition of the breeding role, this status-related growth pattern shares similarities with growth in naked mole-rats and other social vertebrates. Breeders also show a twofold greater lifespan than non-breeders in Fukomys mole-rats, prompting the suggestion that the transition to dominance also sets individuals onto a slower ageing trajectory. To date, there is little evidence to support a physiological basis to lifespan extension in breeders. This assertion is bolstered by the absence of longer telomeres or slower rates of telomere attrition in breeding females compared to non-breeding females residing in groups (Chapter 6), each of which might be expected if breeders age more slowly. I argue that previous studies exploring status-related ageing in captive Fukomys mole-rats have overlooked the importance of demographic processes (and associated behavioural influences) on mortality schedules. Irrespective of the proximate basis of the longer lifespan of breeders, at an interspecific level the social mole-rats are unusually long-lived for their size. A recent large-scale comparative analysis concluded that prolonged lifespan is a general characteristic of all mammalian cooperative breeders, but this conclusion is premature, as in most of the major clades containing both cooperative and non-cooperative species there is no consistent trend towards lifespan extension in cooperative species (Chapter 7). In the case of mole-rats, it seems more likely that their exceptional longevity arises principally from their subterranean habits and related reductions in extrinsic mortality. Overall, these findings demonstrate that cooperative breeding has important consequences for individual life histories, but there is no strong basis for the claim that Damaraland mole-rat societies are markedly different in form than other cooperative breeding societies.
74

Analysis of alpha-2 macroglobulin from the long-lived and cancer-resistant naked mole-rat and human plasma

Thieme, René, Kurz, Susanne, Kolb, Marlen, Debebe, Tewodros, Holtze, Susanne, Morhart, Michaela, Huse, Klaus, Szafranski, Karol, Platzer, Matthias, Hildebrandt, Thomas B., Birkenmeier, Gerd 27 July 2015 (has links) (PDF)
Background: The naked mole-rat (NMR) is a long-lived and cancer resistant species. Identification of potential anti-cancer and age related mechanisms is of great interest and makes this species eminent to investigate anti-cancer strategies and understand aging mechanisms. Since it is known that the NMR expresses higher liver mRNA-levels of alpha 2-macroglobulin than mice, nothing is known about its structure, functionality or expression level in the NMR compared to the human A2M. Results: Here we show a comprehensive analysis of NMR- and human plasma-A2M, showing a different prediction in glycosylation of NMR-A2M, which results in a higher molecular weight compared to human A2M. Additionally, we found a higher concentration of A2M (8.3±0.44 mg/mL vs. and 4.4±0.20 mg/mL) and a lower total plasma protein content (38.7±1.79 mg/mL vs. 61.7±3.20 mg/mL) in NMR compared to human. NMR-A2M can be transformed by methylamine and trypsin resulting in a conformational change similar to human A2M. NMRA2M is detectable by a polyclonal antibody against human A2M. Determination of tryptic and anti-tryptic activity of NMR and human plasma revealed a higher anti-tryptic activity of the NMR plasma. On the other hand, less proteolytic activity was found in NMR plasma compared to human plasma.
75

Nondestructive molecular sex determination of free-ranging star-nosed moles (Condylura cristata)

Price, Nadine 15 January 2014 (has links)
Molecular techniques, particularly noninvasive genetic sampling (NGS) and nondestructive sampling (NDS), are increasingly being used as tools to study the ecology of free-ranging mammals. A specific application of these methods is the molecular sexing of species for which external sex differentiation is challenging. Star-nosed moles (Condylura cristata) are a little-studied species in which females possess a peniform clitoris making them externally indistinguishable from males. To my knowledge, no studies have employed NDS to study any aspect of their ecology. I therefore sequenced fragments of one X-chromosome (Zfx) and two Y-chromosome (Sry and Zfy) genes from known-sex specimens, and designed species-specific primers to co-amplify these loci from hair, claw and fecal samples of 16 star-nosed moles. I found all tissue types were highly (90-100%) reliable for sex determination. I envision that this NDS method will facilitate future capture-and-release studies on the natural history and social structure of this fascinating, semi-aquatic mammal.
76

[en] TESTS OF FIELD AND LABORATORY IN CABRITONULLS INLET SOFT CLAY IN SALVADOR-BAHIA / [pt] ENSAIOS DE CAMPO E LABORATÓRIO NA ARGIDA MOLE DA ENSEADA DO CABRITO, SALVADOR, BAHIA

HELIO MACHADO BAPTISTA 23 April 2001 (has links)
[pt] Este trabalho apresenta os resultados de uma investigação sobre as características geotécnicas do depósito de argila mole da enseada do Cabrito em Salvador-Bahia. Nesta área está em curso a implantação de uma obra de urbanização, visando o assentamento de famílias que habitavam anteriormente no local, em casas construídas sobre palafitas. A determinação das propriedades geotécnicas do solo foi feita através de ensaios de campo e de laboratório. No campo, foram realizados ensaios de piezocone e de dissipação de poro-pressão, além de sondagens com medida de SPT e ensaios de palheta. Para a realização dos ensaios de dissipação de poropressões in situ, foi desenvolvida uma sonda piezométrica, que está apresentada neste trabalho. No laboratório, o programa experimental constou de ensaios de caracterização, triaxiais e de adensamento (incrementais e contínuos). Para os ensaios de adensamento contínuos, foram realizadas algumas modificações no equipamento convencional, que também são descritas neste trabalho. / [en] This work presents and discusses the geotechnical characteristics of the Cabrito's inlet soft clay in Salvador-Bahia. On this area is in course the implantation of an embankment, seeking to locate families that inhabited previously in the place, in houses built on wood piles. The determination of the soil properties was made through geotechnical tests of field and laboratory. For the accomplishment of the tests of dissipation of poropressure in situ, a piezometer probe was developed, that is presented in this work. For the continuos oedometer tests, some modifications were accomplished in a conventional cell, that are also presented in this volume. Finally, the obtained results of physical , of consolidation, of deformation and of resistance characteristics, are analyzed together, in such a way to obtain a better characterization of the properties of the deposit.
77

[en] EXPERIMENTAL STUDY OF THE COMPRESSIBILITY AND CONSOLIDATION CHARACTERISTICS OF A SOFT CLAY / [pt] ESTUDO EXPERIMENTAL DAS CARACTERÍSTICAS DE COMPRESSIBILIDADE E ADENSAMENTO DE UMA ARGILA MOLE

YGOR ALMEIDA NETTO 27 June 2007 (has links)
[pt] No presente trabalho é realizado um estudo experimental das características de compressibilidade e adensamento de argilas moles. Foram realizados ensaios convencionais de adensamento (SIC) e ensaios de adensamento com velocidade constante de deformação (CRS) - em diferentes velocidades - ensaios de adensamento com uma face drenante e ensaios traxiais. As amostras foram remoldadas em laboratório, a partir de uma mistura de bentonita e caulim, na proporção de 98 : 2 em peso, e adensadas istoropicamente, a fim de se garantir uma melhor qualidade quanto à homogeneidade e isotropia do material. Os resultados são obtidos e analisados através das curvas típicas para os ensaios de adensamento. São obtidos os valores dos parâmetros de compressibilidade e de adensamento do material. Por fim é proposto um novo método para obtenção coeficiente de adensamento vertical (Cv) e feita uma análise comparativa com métodos existentes na literatura. / [en] In the present work it is carried out an experimental study of the compressibility characteristics and consolidation of a soft clay. Standard Incremental Consolidation (SIC) and Constant Rate of strain (CRS) - in different speeds - triaxiais tests and consolidation with one drenate tests had been carried trough. The samples had been remoulds in laboratory, from a mixture of bentonita and kaolin, in the ratio 98 : 2 In weight, and confined under isotropic conditions, in order to guarantee one better quality how much to the homogeneity and isotropy of the material. The results are gotten and analyzed through the typical curves for consolidation tests. The values of the parameters of compressibility and consolidation of the material are gotten. Finally a new method for attainment of the vertical consolidation coefficient (Cv) and made a comparative analysis with existing methods in literature is considered.
78

Exploratory and spatial learning abilities in two African mole-rats with different social system. / Exploratory and spatial learning abilities in two African mole-rats with different social system.

MAZOCH, Vladimír January 2008 (has links)
The goal of this study was to examine differences in the exploratory activity, spatial learning and memory between two strictly subterranean rodents with different social systems, solitary silvery mole-rat (Heliophobius argenteocinereus) and social giant mole-rat (Fukomys mechowii) in a maze resembling natural burrows. Although the giant mole-rats showed better performance in most of the parameters of the test, this could not be easily explained by superior learning abilities of social species. The differences found could be more attributed to different motivation in both species. The solitary mole-rat was remarkably more cautious and moved with lower velocity, spent more time in the maze, made more errors and traveled a longer path before reaching the reward box.
79

Desenvolvimento de um enxaguatório bucal com extrato nebulizado de Guapira graciliflora (L.)

Rocha, Ibrahim Vieira 21 February 2017 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2018-06-19T14:04:27Z No. of bitstreams: 1 PDF - Ibrahim Vieira Rocha.pdf: 50898078 bytes, checksum: c4f8b8a31f362dd3548a8bb36cbc1ecf (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2018-07-03T17:47:43Z (GMT) No. of bitstreams: 1 PDF - Ibrahim Vieira Rocha.pdf: 50898078 bytes, checksum: c4f8b8a31f362dd3548a8bb36cbc1ecf (MD5) / Made available in DSpace on 2018-07-03T17:47:43Z (GMT). No. of bitstreams: 1 PDF - Ibrahim Vieira Rocha.pdf: 50898078 bytes, checksum: c4f8b8a31f362dd3548a8bb36cbc1ecf (MD5) Previous issue date: 2017-02-21 / The plants have been a rich source of medicinal agents, serving as a foundation for the synthesis of drugs, and making the Caatinga, like the other biomes, a valuable barn for the discovery of new antimicrobial agents, valuing the ethnobotanical knowledge and its phytogeography. Guapira graciliflora Lundell belonging to the family Nyctaginaceae is popularly known as João-Mole and has been shown to be a strong candidate with antimicrobial action. This work aimed to develop a new mouthwash formulation from the G. graciliflora Lundell nebulized extract, in order to decrease and control the dental biofilm. The extract obtained by spraying was submitted to a toxicity test in Artemia salina. Phytochemical and microbiological screenings of the nebulized extract of joão-mole, for determination of its secondary metabolites and its major compound, and evaluation by microdilution, against the microorganisms involved with the formation of the dental biofilm: Streptococcus mutans, Streptococcus salivarius, Streptococcus parasanguis and Streptococcus oralis. Quantitative phytochemical screening indicated the presence of flavonoids in the concentration of 13.89mg mL-1, and tannins 5.96mg mL-1. Identification of the major component was performed using Mass Spectrometry with electrospray ionization (ESI-MS), suggesting the presence of pinitol, rutin and kaemptoferol. G. graciliflora Lundell, and the final formulation showed antimicrobial activity against three of the four strains tested. The physicochemical analyzes showed that the nebulized extract is highly hygroscopic, has low density, poorly acidic pH and loss by desiccation within the parameters recommended by the Brazilian Pharmacopoeia. A preformulation study was performed with pharmaceutical excipients and the nebulized extract through Thermal Analysis, Fourier Transform Spectroscopy (FT- IR). The compatibility study demonstrated that sodium lauryl sulfate, propylparaben and sorbitol were the excipients chosen to make up the formulation. As for the lots produced, the pH, viscosity and organoleptic characteristics observed after 24 hours of manipulation and at the end of thermal stress and centrifugation tests presented stability, thus representing an excellent herbal alternative for the prevention and control of dental biofilm. / As plantas têm sido uma rica fonte de agentes medicinais, servindo de alicerce para a síntese de fármacos, e tornando a Caatinga, como os demais biomas, um valioso celeiro para a descoberta de novos agentes antimicrobianos, valorizando o conhecimento etnobotânico e a sua fitogeografia. Guapira graciliflora Lundell pertencente à família Nyctaginaceae é conhecida popularmente como joão-mole e tem se mostrado um forte candidato com ação antimicrobiana. Este trabalho teve como objetivo desenvolver uma nova formulação de enxaguatório bucal a partir do extrato nebulizado de G. graciliflora Lundell, com o intuito de diminuir e controlar o biofilme dentário. O extrato obtido por aspersão foi submetido a teste de toxicidade em Artemia salina. Realizou-se screenings fitoquímico e microbiológico do extrato nebulizado de joão-mole, para determinação de seus metabolitos secundários e seu composto majoritário, e avaliação, por micodiluição, frente aos microrganismos envolvidos com a formação do biofilme dentário: Streptococcus mutans, Streptococcus salivarius, Streptococcus parasanguis e Streptococcus oralis. O screening fitoquímico quantitativo indicou a presença de flavonoides na concentração de 13,89mg mL-1,e taninos 5,96mg mL-1. A identificação do componente majoritário foi realizada através da Espectrometria de Massas com ionização por eletrospray (ESI-MS), sugerindo a presença de pinitol, rutina e kaemptoferol. G. graciliflora Lundell, e a formulação final apresentaram atividade antimicrobiana frente a três das quatro cepas testadas. As análises físico-químicas mostraram que o extrato nebulizado é altamente higroscópico, tem baixa densidade, pH fracamente ácido e perda por dessecação dentro dos parâmetros recomendados pela Farmacopéia Brasileira. Um estudo de préformulação foi realizado com excipientes farmacêuticos e o extrato nebulizado através de Análise Térmica, Espectrotroscopia com Transformada de Fourier (FT-IR). O estudo de compatibilidade demonstrou que o lauril sulfato de sódio, propilparabeno e sorbitol foram os excipientes eleitos para compor a formulação. Quanto aos lotes produzidos, o pH, viscosidade e as características organolépticas observadas após 24 horas de manipulação e ao término dos testes de estresse térmico e de centrifugação apresentaram estabilidade, representando assim, uma excelente alternativa fitoterápica para o prevenção e controle do biofilme dental.
80

Diffusive properties of soft condensed matter systems under external confinement / Diffusive properties of soft condensed matter systems under external confinement

Diego de Lucena CamarÃo 27 August 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Nesta tese estudamos a influÃncia de potenciais de confinamento externos nas propriedades dinÃmicas de sistemas de matÃria condensada mole. Analisamos as propriedades difusivas de dois sistemas especÃficos utilizando simulaÃÃes computacionais (DinÃmica Molecular de Langevin e DinÃmica Browniana). No CapÃtulo 1, introduzimos o tÃpico sobre matÃria condensada mole. Mostramos vÃrios aspectos teÃricos e experimentais neste tipo de sistema. Fazemos uma breve introduÃÃo ao tÃpico de difusÃo, onde discutimos os principais aspectos do movimento Browniano. Introduzimos o problema de difusÃo em linha (SFD, do inglÃs "single-file diffusion") e o discutimos, teorica e experimentalmente, no contexto de sistemas de matÃria condensada mole. No CapÃtulo 2, introduzimos os mÃtodos computacionais utilizados nesta tese. Discutimos os mÃtodos de DinÃmica Molecular e suas variantes, o mÃtodo de DinÃmica de Langevin e DinÃmica Browniana. TambÃm introduzimos algoritmos de integraÃÃo utilizados nos capÃtulos posteriores. Nos Caps. 3, 4 e 5, analisamos dois sistemas distintos, (i) um sistema de partÃculas de Yukawa confinadas em um canal parabÃlico quasi-unidimensional (q1D) e (ii) um sistema de colÃides magnÃticos sob a influÃncia de um potencial parabÃlico e uma modulaÃÃo periÃdica externa ao longo da direÃÃo nÃo confinada. No primeiro sistema, estudamos a transiÃÃo do regime de difusÃo em linha (SFD) para o regime de difusÃo normal (2D). No segundo sistema, estudamos os efeitos de vÃrios parÃmetros que caracterizam o sistema (e.g., a magnitude do campo magnÃtico externo e a presenÃa da modulaÃÃo periÃdica externa) em suas propriedades dinÃmicas. Finalmente, apresentamos um sumÃrio dos principais resultados obtidos nesta tese e mostramos algumas questÃes em aberto como perspectivas para pesquisas futuras na Ãrea de difusÃo em sistemas de matÃria condensada mole. / In this thesis we study the influence of external confinement potentials on the dynamical properties of soft condensed matter systems. We analyze the diffusive properties of two specific systems by means of Langevin and Brownian Dynamics simulations. In Chapter 1, we introduce the subject of soft condensed matter. We show several theoretical and experimental aspects of these type of systems. We make a brief introduction to the topic of diffusion, where we discuss main aspects of Brownian motion. We introduce the single-file diffusion (SFD) problem and discuss it in the context of soft condensed matter systems, both theoretically and experimentally. In Chapter 2, we introduce the computational method used in this thesis. We discuss Molecular Dynamics (MD) and its variants, Langevin and Brownian Dynamics simulations. We also introduce numerical algorithms used in the following chapters. In Chapters 3, 4 and 5, we analyze two different systems, namely (i) a system of interacting Yukawa particles confined in a parabolic quasi-one-dimensional (q1D) channel and (ii) a system of magnetic colloidal particles under the influence of both a parabolic confinement potential and a periodic external modulation along the unconfined direction. In the former, we study the transition from the single-file diffusion (SFD) regime to the two-dimensional (2D) diffusion regime. In the latter, we study the influence of several parameters that characterizes the system, e.g., the strength of an external magnetic field and the periodic modulation along the unconfined direction, on its dynamical properties. Finally, we present the summary of the main findings reported in this thesis and we show some open questions as perspectives for future research in the field of diffusion in soft condensed matter systems.

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