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La plupart des épisodes de pollution atmosphérique intense apparaissent lors des situations des vents faibles. Les modèles de pollution atmosphérique surestiment ou sous-estiment les concentrations dans ces conditions, en fonction des modèles des écarts-types (σi avec i=x,y,z) de dispersion auxquels ils sont associés. Ceci a été mis en évidence dans la première partie de cette thèse où on a évalué l’efficacité de 5 modèles de dispersion associés à 6 modèles des écarts-types, en se servant de 5 bases des données internationales. Dans la deuxième partie, nous avons développé deux modèles écarts-types de dispersion (S_LMEE_Ond et S_LMEE_Taylor) à partir de bases de données expérimentales appropriées. On a montré ainsi que pour les vents faibles, la vitesse instantanée du vent est non-stationnaire et qu’elle est caractérisée par des fluctuations rapides (aléatoires ou turbulentes) et des fluctuations lentes (organisées). Les fluctuations turbulentes favorisent le mélange des particules à l’intérieur du panache et les fluctuations lentes entrainent leur transport horizontal. Les modèles des écarts-types développés dans cette thèse semblent mieux appropriés pour étudier la dispersion des particules par faibles vents. Le modèle S_LMEE_Taylor est fonction du module moyen de la vitesse du vent (V) et des écarts-types des fluctuations organisées (σu et σv). Des modèles ARX multivariables et autorégressifs ont été développés dans un environnement MATLAB pour la prédiction de ces paramètres avec un horizon de 10 mn et 30 min. / The most intense air pollution episodes occur in situations of low winds. The air pollution models overestimate or underestimate the levels in these conditions, according to models of standard deviations (σi with i = x, y, z) dispersion which they are associated. This was highlighted in the irst part of this thesis where we evaluated the efficacy of five models of dispersal patterns associated with six standard deviations, using five international databases. In the second part, we have developed two models of dispersal standard deviations (S_LMEE_Ond and S_LMEE_Taylor) from experimental databases appropriate. It has been shown and for light winds, the wind speed is non-stationary and ischaracterized by rapid fluctuations (random or turbulent) and slow fluctuations (organized). Turbulent fluctuations promote mixing of particles within the plume and slow fluctuations leading to their horizontal transport. Models of deviations developed in this thesis seem more appropriate to study the dispersion of particles by low winds. The model is based on the module S_LMEE_Taylor average wind speed (V) and standard deviations of fluctuations organized (σu and σv). ARX models and multivariate autoregressive have been developed in MATLAB to predict these parameters with a 10 min and 30 min.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, 2009. / Submitted by Allan Wanick Motta (allan_wanick@hotmail.com) on 2010-04-01T12:24:19Z No. of bitstreams: 1 2009_FranciscoPNJunior.pdf: 873921 bytes, checksum: b8c21f11bac2583450a9d6fe651959a3 (MD5) / Approved for entry into archive by Lucila Saraiva(lucilasaraiva1@gmail.com) on 2010-05-21T16:26:57Z (GMT) No. of bitstreams: 1 2009_FranciscoPNJunior.pdf: 873921 bytes, checksum: b8c21f11bac2583450a9d6fe651959a3 (MD5) / Made available in DSpace on 2010-05-21T16:26:57Z (GMT). No. of bitstreams: 1 2009_FranciscoPNJunior.pdf: 873921 bytes, checksum: b8c21f11bac2583450a9d6fe651959a3 (MD5) Previous issue date: 2009 / Objetivos: comparar a eficácia visual para longe, perto e intermediário com e sem correção das lentes intraoculares multifocais difrativas apodizadas Restor Asférica - SN6AD3 - e Restor Esférica - SN60D3 -, além de avaliar a performance visual destas lentes por meio do exame de aberrometria. Metodologia Científica: 68 olhos foram submetidos à facoemulsificação com implante de lente intraocular multifocal Restor Asférica e Restor Esférica. No 3 mês de pós-operatório, foram avaliadas, em condições fotópicas (85 cd/m2), as acuidades visuais, com e sem correção, para longe (6 metros), perto (33 cm) e intermediário (60 cm). Todos os pacientes foram submetidos ao exame de aberrometria e comparados os resultados por meio de testes estatísticos paramétricos e não-paramétricos (teste de Kruskal-Wallis e teste t-Student). Resultados: Os pacientes analisados (72,23% femininos) tinham idade média de 70 anos, variando de 58 a 79 anos. A dioptria das lentes intraoculares multifocais implantadas nos pacientes deste estudo apresentouse dentro dos valores mais comuns, onde 83,8% dos pacientes usaram lentes intraoculares com medidas entre 20 e 24 dioptrias, com uma média de 21,4 e com desvio padrão de 2,1. A medida da acuidade visual média dos pacientes com lente Restor Asférica foi pior na distância intermediária, onde a Acuidade Visual foi, aproximadamente, de 20/32 (J4) com e sem correção. Para perto e longe, a AV das lentes asféricas ficou em torno de 20/20 com correção. Os pacientes com lente Restor Esférica também apresentaram acuidade visual, em média, de 20/20, para perto e para longe, com correção. Na distância intermediária a AV foi, em média, de 20/30 (J3) sem correção e 20/32 com correção. Nessas lentes, a acuidade visual para longe, sem correção, alcançou a média de 20/25. Não houve diferenças estatisticamente significativas entre as lentes esféricas e asféricas nas acuidades visuais para perto sem correção (p=0,345), para perto com correção (p=0,903), para intermediário sem correção (p=0,798), para intermediário com correção (p=0,743) e para longe com correção (p=0,133). A lente Restor Asférica apresentou melhor acuidade visual para longe sem correção (p=0,000). Não existiu diferença estatística entre as medidas do equivalente esférico (p=0,965) e das aberrações do olho (aberração total 5mm - p=0,273) (aberração total 6mm p=0,742) (HOA 5mm p=0,556) (HOA 6mm p=0,339) (aberração esférica 6mm p=0,360) entre a lente asférica e esférica. Conclusões: Não foram observadas diferenças estatisticamente significativas entre as lentes multifocais Restor Asférica e Restor Esférica nas visões de perto e intermediário com e sem correção. A Restor Asférica alcançou melhor acuidade visual para longe, sem correção, do que a Restor Esférica. Quando o erro refracional foi corrigido, a acuidade visual para longe das lentes se aproximou e deixou de ter significância estatística, além da inexistência de diferença entre as medidas do equivalente esférico e das aberrações do olho entre a lente asférica e esférica. _______________________________________________________________________________________ ABSTRACT / PURPOSE: To compare distance, intermediate and near visual acuity (VA) ,uncorrected and best corrected, and ocular aberrations in patients who had multifocal aspherical and spherical apodized diffractive intraocular lens (IOL) implantation (Restor, Alcon). METHODS: The best corrected visual acuity (BCVA), uncorrected visual acuity (UCVA), distance corrected near visual acuity (DCNVA), uncorrected near visual acuity (UCNVA), uncorrected intermediate visual acuity (UCIVA), distance corrected intermediate visual acuity (DCIVA) and ocular aberrations were measured in 68 eyes who had multifocal aspherical and spherical apodized diffractive intraocular lens (IOL) implantation (Restor, Alcon). Ocular aberrations with a 5.0 mm and 6.0 mm pupil were measured with a Hartmann-Shack aberrometer. All patients were followed for 3 months. RESULTS: The mean age of the 25 women and 9 men was 70 years ( range of 58 the 79 years). There were no statistically significant differences between eyes in postoperative uncorrected and best corrected near and intermediate visual acuities after a follow-up of 3 months. The dioptry of the implanted multifocal intraocular lenses was presented between the most common values. 83.8% of the patients had implanted intraocular lens between 20 and 24 dioptries (mean 21,5 D 2,0 D). The mean best corrected visual acuity (BCVA), distance corrected near visual acuity (DCNVA), uncorrected near visual acuity (UCNVA) were 20/20 in aspherical group. In this group, uncorrected and best corrected intermediate visual acuity (UCIVA) were worst (mean 20/32- J4 ). In the spherical group, the mean best corrected visual acuity (BCVA) and distance corrected near visual acuity (DCNVA) were 20/20. The mean uncorrected intermediate visual acuity (UCIVA) was 20/30 and the mean best distance corrected intermediate visual acuity (DCIVA) was 20/32. In spherical group, the mean uncorrected visual acuity (UCVA) was 20/25. There were no statistically significant differences between the groups in best corrected visual acuity (BCVA) (p=0,133), distance corrected near visual acuity (DCNVA) (p=0,903), uncorrected near visual acuity (UCNVA) (p=0,345), uncorrected intermediate visual acuity (UCIVA) (p=0,798), distance corrected intermediate visual acuity (DCIVA) (p=0,743) . The uncorrected visual acuity (UCVA) was better in patients with an AcrySof ReSTOR Aspherical SN6AD3 (p=0,000).There were no statistically significant differences in spherical equivalent (p=0,965), total aberration with 5 mm pupil diameter (p=0,273), total aberration with 6 mm pupil diameter (p=0,742), high-order aberration(HOA) with 5 mm pupil diameter (p=0,556), high-order aberration(HOA) with 6 mm pupil diameter (p=0,339) and spherical aberration (p=0,360) between the groups. CONCLUSIONS: There were no statistically significant differences between eyes in postoperative best corrected visual acuity (BCVA), distance corrected near visual acuity (DCNVA), uncorrected near visual acuity (UCNVA), uncorrected intermediate visual acuity (UCIVA), distance corrected intermediate visual acuity (DCIVA) and ocular aberrations. The uncorrected visual acuity (UCVA) was better in patients with an AcrySof ReSTOR Aspherical SN6AD3.

Orientadores: Newton Kara Jose, Vital Paulino Costa / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-01T21:29:53Z (GMT). No. of bitstreams: 1 Souza_OsiasFranciscode_D.pdf: 16950441 bytes, checksum: 80c3608581c578b98f0c8ab772af9a29 (MD5) Previous issue date: 2002 / Resumo: Introdução e objetivos: A evolução da vitrectomiavia pars plana (VVPP) levou ao desenvolvimento de equipamentos especializados e aumentou a necessidade de novos sistemas de visibilização retiniana. O presente estudo analisou os sistemas de visibilização Landers e sistema de lentes de inversão operatória (ROLS), em VVPP, comparando os tempos cirúrgicos, o número de trocas de lentes de visibilização, o número de troca fluido gasosa (TFG), o uso de perfluorocarbono líquido (PFCL), o número de realizações de depressão escleral intra-operatória, as dificuldades de aplicação de laser periférico, acuidade visual fmal e resultado anatômico. Pacientes e Métodos: Estudo comparativo entre VVPP realizadas com os sistemas ROLS e Landers. Foram analisados retrospectivamente 117 VVPP realizadas em 87 pacientes, no período entre Dezembro de 1996 e Agosto de 1998, divididas em 2 grupos, de acordo com o sistema de visibilização utilizado, avaliando-se as VVPP primárias e reoperações. O grupo 1 (G1) foi formado com 54 cirurgias e utilizou o sistema Landers. O grupo 2 (G2) foi formado com 63 cirurgias e utilizou o sistema ROLS. Não houve diferenças estatisticamente significativas entre os dois grupos nos dados pré-operatórios, com exceção para a AV inicial (p<0.05) ...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: Introduction: Since the introduction of PPV (pars plana vitrectomy), techniques have improved continuously in order to provide clear and complete view of the surgical field. The present study analyzed the panoramic viewing system (PVS) Reinverting Operating Lens System (ROLS) and the plano-convex Landers lens system in PPV, and compared the surgical time, the number of lens and air-fluid exchanges, use of PFCL, scleral depression during the procedure, difficulty of laser application, final visual acuity and anatomic success. Patients and Methods: The authors retrospectively compared the records of 117 PPV, 87 patients, performed from December 1996 up to August 1998. The PPV was divided into two groups. Group 1, Landers system, included 54 surgeries, and group 2, ROLS, ineluded 63 surgeries. There were no statistical significant differences regarding pre-operative parameters, except for the initial VA Introduction: Since the introduction of PPV (pars plana vitrectomy), techniques have improved continuously in order to provide clear and complete view of the surgical field. The present study analyzed the panoramic viewing system (PVS) Reinverting Operating Lens System (ROLS) and the plano-convex Landers lens system in PPV, and compared the surgical time, the number of lens and air-fluid exchanges, use of PFCL, scleral depression during the procedure, difficulty of laser application, final visual acuity and anatomic success. Patients and Methods: The authors retrospectively compared the records of 117 PPV, 87 patients, performed from December 1996 up to August 1998. The PPV was divided into two groups. Group 1, Landers system, included 54 surgeries, and group 2, ROLS, ineluded 63 surgeries. There were no statistical significant differences regarding pre-operative parameters, except for the initial VA...Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Oftalmologia / Doutor em Ciências Médicas

Orientador: Edison Bittencourt / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-02T10:01:16Z (GMT). No. of bitstreams: 1 RivasLeon_Harold_M.pdf: 2946304 bytes, checksum: 94b0fb190bf73338870922ff04fb3676 (MD5) Previous issue date: 2002 / Resumo: Na indústria de dispositivos ópticos o vidro, material tradicional, tem sido progressivamente substituído pelos materiais poliméricos por ter estes últimos melhores propriedades ópticas e mecânicas, além de menor custo de produção, e oferecer maior conforto e segurança. O polímero mais usado na fabricação de lentes oftálmicas é obtido por polimerização do dietilenoglicol biscarbonato de alila (CR39). Os principais processos de cura deste monômero são bastante elaborados e demorados, o que eleva significativamente os custos de produção, permitem pouco controle de processo e apresentam um alto índice de rejeição. Estes processos são baseados na iniciação por calor, necessitando 60-72 horas para a cura isotérmica e 18-22 horas para quando usada uma taxa crescente de temperatura. O objetivo deste trabalho é desenvolver e otimizar métodos de cura utilizando polimerização térmica ou iniciada por irradiação ultravioleta, apoiando­se na determinação das principais constantes cinéticas dos sistemas de monômero-iniciador assim como caracterizar os materiais obtidos em quanto a suas propriedades mecânicas, óticas e térmicas. O estudo permitiu reduzir o tempo de cura do CR39 tanto quando realizada a polimerização por aquecimento ou por irradiação com luz UV. As lentes obtidas em estas condições têm propriedades ópticas, mecânicas e térmicas adequadas que permitem seu uso como dispositivos ópticos / Abstract: In the industries of optical lenses, glass, the material traditionally used, has been progressively substituted by polymeric materials, due to its better mechanical and optical properties, lower cost and higher comfort and safety. The polymer mostly used to produce ophthalmic lenses is obtained from the polymerization of diethylene glycol bis (ally carbonate), commercially known as CR39. Today's CR39 curing processes are elaborate and slow, have high production costs, allowing insufficient process control and presenting a high rejection of defective lenses. These polymerization processes are initiated by heat. It's demand 60-72 hours for an isothermal cure and 18-22 hours when the temperature is increased under adequate control during the polymerization process. In this work, curing processes using both, heat and ultraviolet light initiation, were developed and optimized, determining the necessary kinetic constant for specific monomer-initiator systems and characterizing mechanical, optical and thermal properties of lenses obtained. This study permitted the reduction of CR39 curing time both for thermal and ultraviolet initiated polymerization. Optical, mechanical and thermal properties obtained were suitable for commercial utilization of the lenses obtained. / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química

Le sommeil est présent chez pratiquement tous les animaux mais a atteint le plus haut niveau d’organisation chez les mammifères et les oiseaux avec le sommeil à ondes lentes et le sommeil paradoxal. De nombreuses études ont suggéré que le sommeil est généré par le cerveau pour ses propres besoins. L’oscillation lente est une caractéristique électroencéphalographique du sommeil à ondes lentes se traduisant par une alternance entre des états actif et silencieux du réseau thalamocortical. Elle a attiré le focus de plusieurs études étant donné son implication dans la plasticité synaptique et la consolidation de la mémoire. Plusieurs questions restent néanmoins en suspens. Quel est le rôle du thalamus dans l’oscillation lente? Quelles conditions mènent à l’état silencieux? Y a-t-il une variabilité entre espèces dans la synchronisation des ondes lentes? Dans la première étude de cette thèse, nous montrons que le thalamus est crucial à la genèse et à la propagation de l’oscillation lente alors que le cortex a la propriété intrinsèque de la restaurer en absence d’afférence fonctionnelle. Dans la seconde étude, nous nous intéressons aux conditions qui mènent à l’initiation des états silencieux dans le néocortex. Nous avons trouvé que l’inhibition dépendante du chlore est impliquée dans la terminaison des états actifs et que les afférences thalamocorticales jouent un rôle dans la synchronisation des états silencieux. Dans la troisième étude, nous comparons le niveau de synchronisation de l’oscillation lente dans les régions somatosensorielle et associative du néocortex chez le chat et le lapin. Nous rapportons que la synchronisation de l’oscillation lente corrèle avec le niveau de gyrification du cortex cérébral et le niveau hiérarchique dans le traitement de l’information d’une région néocorticale. Nous concluons que l’oscillation lente est une propriété intrinsèque du néocortex qui émerge du dialogue entre le néocortex et le thalamus, de la balance entre l’inhibition et l’excitation dans le réseau néocortical et dont la synchronisation a évolué avec le développement du cortex cérébral. / Sleep is a defining feature of animals that achieved the highest degree of organization in mammals with two distinct types of sleep: the slow wave sleep (SWS) and the rapid eye movements sleep. A large body of evidences suggests that the sleep is generated by the brain to fulfill its own need. Among the electroencephalographic signatures of SWS and anesthesia, the slow oscillation (&lt; 1 Hz), a rhythmic alternation of active and silent states of the thalamocortical network, has attracted a lot of attention owing to its implication in synaptic plasticity and memory consolidation. Several questions remain unanswered on the mechanisms underlying the slow oscillation. For instance, what is the role of the thalamus in the slow oscillation? Which conditions lead to the onset of the silent state? Is there inter-species variability in the synchronization? In the first study of this thesis, we have investigated the respective contribution of the neocortex and the thalamus in the generation of the slow oscillation. We report that the thalamus is crucial to the generation and propagation of the active states of the slow oscillation while the neocortex has the intrinsic ability to recover the slow oscillation in absence of afferents. In the second study, we address the question regarding the conditions that lead to the onset of the silent state in the neocortex. We have found that chloride-mediated inhibition and functional thalamocortical afferents are involved in terminating the active states. In the third study, we compare the synchronization of the slow oscillation in the somatosensory and associative cortices of cats and rabbits. We have found that the synchronization of the slow waves correlates with the level of gyrification of the cerebral cortex and the hierarchical level of information processing of a neocortical region. We conclude that the slow oscillation is an intrinsic property of the neocortex that emerges from the dialogue between the neocortex and thalamus, the balance of inhibition and excitation in the neocortical network and that the synchronization of the slow oscillation evolved with the development of the cerebral cortex.

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Com o crescimento do setor de lentes de contato houve também um aumento de casos de ceratite por Acanthamoeba spp. A falta de cuidados na limpeza e manutenção de lentes pode levar à ocorrência dessa doença. Nesse estudo avaliou-se o perfil de 196 usuários de lentes de contato de clínicas particulares e do Hospital de Clínicas de Porto Alegre (HCPA), através de entrevistas, para conhecer os tipos de lentes usadas, soluções de limpeza, conhecimento da patologia, entre outros, no período de maio de 2015 a outubro de 2016. No HCPA, 112 usuários (57,1%) responderam ao questionário enquanto nas clínicas particulares 84 usuários (42,9%) participaram da pesquisa. A maioria dos entrevistados eram mulheres 116 (59,2%), brancas 173 (89,6%) e com ensino superior 91 (46,4%). O uso de lentes de contato gelatinosas foi mais frequente nas clínicas particulares (78,6%) enquanto no HCPA as lentes mais usadas eram Rígidas Gás Permeáveis (RGP) (60,7%). A maioria dos pacientes usava solução multiuso na limpeza de suas lentes 131 (66,8%). Desconheciam que uma ameba poderia ser causadora da patologia 143 entrevistados (73,0%). Além disso, paralelamente, foi pesquisada a ocorrência de 25 casos de ceratite por Acanthamoeba spp. (nos anos de 1994 a 2015) em uma clínica particular e no HCPA. Foram analisados dados encontrados nos prontuários médicos, como os citados acima entre outros. A maioria eram mulheres (68,0%), brancas (44,0%) e com curso superior (40,0%). Em relação ao uso de lentes de contato a maioria dos pacientes usava lentes gelatinosas (66,7%). Sobre a limpeza e desinfecção, 64,0% utilizavam solução multiuso, mas usavam também soro fisiológico (48,0%) e água (36,0%). A falta de suspeição e a corrente confusão devido aos achados biomicroscópicos leva a um diagnóstico errado quase sempre confundido com herpes simples (36,0%) como mostra o resultado encontrado. Ações que auxiliem os usuários de lentes de contato e a continuidade do levantamento de casos de ceratite por Acanthamoeba spp. seriam necessárias para um conhecimento maior da patologia e consequente sucesso no tratamento. / The growth of the contact lens sector is responsible by the increase Acanthamoeba spp. keratitis cases. The lack of care in cleaning and maintenance of lenses can lead to the occurrence of this disease. In this study, the profile of 196 users of contact lenses from private clinics and Hospital de Clínicas de Porto Alegre (HCPA) was evaluated through interviews, to know the kind of lenses used, cleaning solutions, knowledge of pathology, among others from May 2015 to October 2016. At the HCPA, 112 users (57.1%) answered the questionnaire while in the private clinics 84 users (42.9%) participated of the survey. Most of the interviewees were women 116 (59.2%), white 173 (89.6%) and higher education 91 (46.4%). Soft contact lenses were the most frequent in private clinics (78.6%) while in HCPA the most used lenses were Rigid Permeable Gas (RGP) (60.7%). Most patients wore a multipurpose lens cleaning solution (66.8%), 143 (73.0%) of the interviewees, did not know that an amoeba could be the causer of keratitis. In addition, a survey the occurrence of 25 cases of keratitis caused by Acanthamoeba spp. was investigated (from 1994 to 2015) in a private clinic and at the HCPA. We analyzed data found in medical records, such as those cited above, among others. The majority were women (68.0%), white (44.0%) and higher education (40.0%). Regarding to the use of contact lenses, most patients used gel lenses (66.7%). Regarding to the cleaning and disinfection, 64.0% used multipurpose solution, but they also used saline solution (48.0%) and water (36.0%). Lack of suspicion and the current confusion due to the biomicroscopic findings leads to a misdiagnosis ordinarily confused with herpes simplex (36.0%) we found. Actions that assist the wearers of contact lenses and the continuity of the survey of Acanthamoeba keratitis cases would be necessary for a better knowledge of the pathology and consequent success in the treatment.