O osso alógeno fresco congelado e o Bio-Oss® (OBM) são materiais conhecidos como substitutos ao osso autógeno em cirurgias de levantamento de seio maxilar. O objetivo deste estudo foi avaliar clínica, histológica e histomorfometricamente o processo de reparo de enxertos alógenos com e sem a utilização de OBM, utilizados em técnicas de levantamento de seio maxilar em humanos. Neste estudo do tipo prospectivo, randomizado, tipo série de casos, comparativo, foram operados 34 seios maxilares de pacientes de ambos os sexos, que apresentavam um rebordo ósseo residual com altura máxima de 5 mm na região de seios maxilares para reconstrução em altura para cirurgias de levantamento de seio maxilar prévia à reabilitação por implantes. Os pacientes foram divididos em a) Grupo Controle: Dezessete (17) seios maxilares enxertados somente com a utilização de osso alógeno e b) Grupo Teste: 17 seios maxilares reabilitados com osso alógeno e OBM, na proporção de 2:1. Seis meses após a enxertia, no momento da instalação dos implantes, amostras ósseas foram coletadas por meio de trefinas para análise histológica e histomorfométrica. Os dados da investigação foram submetidos ao teste t de Student para amostras independentes empregado para comparações entre os dois grupos, Mann-Whitney e testes de correlação foram aplicados. 29 pacientes com uma média de idade de 51,32 anos (± 6,44), foram divididos em grupos controle (17) e teste (12), sendo 34 seios avaliados no total. Não houve diferença estatística entre os grupos com relação à idade (p = 0,23) e ao gênero (p = 0,56). Mediana do torque de inserção dos implantes foi de 32N para o grupo controle, e 45N para o grupo teste (p < 0,0001). Taxa de sucesso no grupo controle foi de 93,02% e 100% no grupo teste. Análise histológica apresentou no grupo controle osso alógeno residual com lacunas osteocíticas vazias e padrão lamelar; osso neoformado com lacunas osteocíticas com osteócitos viáveis e padrão imaturo; osteoblastos em íntimo contato matriz osteóide, formando pontes entre os blocos de osso alógeno e osso neoformado; osteoclastos em proximidade às áreas remodelação óssea; ausência de sinais de infiltrado inflamatório; tecido conjuntivo; e no grupo teste, todos os ítens acima e osso bovino mineral. Histomorfometria: material enxertado remanescente (p = 0,74); osso alógeno remanescente (35.78% ± 6.21% grupo controle, 19.72% ± 10.42% grupo teste; p < 0,0001); OBM remanescente no grupo teste (14,78% ± 8,67); osso neoformado (11.94% ± 1.71% grupo controle, 25.79% ± 8.76% grupo teste; p < 0,001); osso total (47.72% ± 5.6% grupo controle, 58.96% ± 8.1% grupo teste; p < 0,001); tecido conjuntivo (52.27% ± 5.6% grupo controle, 41.45% ± 8.4% grupo teste; p < 0,01). Adicionar OBM ao osso alógeno em cirurgias de levantamento de seio maxilar mostrou-se uma técnica de enxertia eficaz para a instalação de implantes. Resultou em maior torque de inserção, porcentagens maiores de osso neoformado e osso total, permitindo a instalação de implantes e reabilitação protética funcional. / Allograft fresh frozen bone and Bio-Oss are knows as autogenous bone materials substitutes in maxillary sinus lifting. The aim of this study was to evaluate clinical, histological and histomorphometrically the process of repair with and without the association of BBM in maxillary sinus augmentation. In this prospective, randomized, comparative case series study, 34 maxillary sinuses were augmented, which had a residual bone ridge with a maximum height of 5 mm in maxillary sinus reconstruction region at the time for surgery of maxillary sinus prior to rehabilitation by implants. Patients were divided into a) control group: seventeen (17) grafted maxillary sinuses with only allograft bone and b) test group: 17 maxillary sinuses rehabilitated with allograft bone and BBM in a 2:1 ratio. Six months after grafting, at time of implant placement, bone samples were collected using a trephine burr for histological and histomorphometrical analysis. The research data were subjected to Student\'s t test for independent samples used for comparisons between two groups, Mann - Whitney and correlation tests were applied. 29 patients with a mean age of 51.32 years (± 6.44), were divided into control group (17) and test (12), with 34 maxillary sinuses evaluated in total. There was no statistical difference between the groups regarding to age (p = 0.23) and gender (p = 0.56). Median insertion torque of the implants was 32N for the control group and 45N for the test group (p < 0.0001). Survival rate in the control group was 93.02% and 100% in the test group. Histological analysis showed, at the control group, residual allograft bone with empty osteocytic lacunae and lamellar pattern; newly formed bone with osteocytic lacunae with viable osteocytes and immature pattern; osteoblasts in close contact with osteoid matrix, forming bridges between the blocks of allograft bone and new bone formation; osteoclasts in bone remodeling surrounding areas; no evidence of inflammatory infiltrate; connective tissue; and in the test group, all the items above and bovine bone mineral. Histomorphometry: graft remaining material (p = 0.74); remaining allogenous bone (35.78% ± 06.21% control group, 19.72% ± 10:42% test group, p < 0.0001); BBM remaining in the test group (14.78% ± 8.67); newly formed bone (11.94% ± 1.71% control group, 25.79% ± 8.76% test group, p < 0.001); total bone (47.72% ± 5.6% control group, 58.96% ± 8.1% test group, p < 0.001); connective tissue (52.27% ± 5.6% control group, 41.45% ± 8.4% test group, p < 0.01). Adding bovine bone mineral to allogenous bone in maxillary sinus surgery proved to be an effective technique of grafting for implant placement. It resulted in higher insertion torque, higher percentages of new bone formation and total bone, allowing installation of implants and functional loading.

A técnica de inseminação artificial (IA) por laparoscopia em ovinos foi utilizada pela primeira vez em 1982, o que tornou viável a utilização econômica do sêmen congelado nesta espécie. Os experimentos foram realizados com o objetivo de determinar as taxas de prenhez de ovelhas inseminadas por laparoscopia, utilizando 50 x 106 espermatozóides descongelados e capacitados in vitro. No experimento 1, foi utilizado sêmen de um reprodutor e 67 ovelhas com estros sincronizados, divididas aleatoriamente entre os grupos: sêmen congelado (SC1) e sêmen congelado capacitado in vitro (SCC1). As ovelhas foram submetidas à IA, com 50x106 espermatozóides, 56 e 60 horas, respectivamente, após a retirada das esponjas impregnadas com progesterona. No grupo SCC1, a taxa de prenhez foi de 48,39% (15/31) significativamente superior a do grupo SC1 de 25% (9/36). No experimento 2, utilizou-se um reprodutor e 100 ovelhas com os estros sincronizados, distribuídas aleatoriamente entre três grupos: sêmen fresco (SF2), SC2 e SCC2. Nos grupos SF2 e SC2 as fêmeas foram inseminadas com 100x106 espermatozóides e 56 horas após a retirada da progesterona. No grupo das fêmeas inseminadas com espermatozóides capacitados in vitro, utilizou-se 50x106 espermatozóides e um intervalo de 60 horas após retirada da progesterona. As taxas de prenhez diagnosticadas nos diferentes grupos experimentais foram: SF2 60,9% (25/41), SC2 56,70% (17/30) e SCC2 44,90% (13/29), não existindo diferença estatística entre os grupos. Os experimentos realizados mostraram a viabilidade doemprego, na espécie ovina, da IA por laparoscopia utilizando 50x106 espermatozóides descongelados e capacitados in vitro. / The ovine artificial insemination (AI) by laparoscopy was described the first time in 1982, since this time frozen semen became a tool for use under field conditions. Today one research goal is to achieve high preganancies rates after AI using a reduced number of frozen/thawed spermatozoa per dosis. The experiments were carried out with the objective to determine the pregnancy rate of ewes inseminated by laparoscopy, using 50 x 106 thawed and in vitro capacited spermatozoa. In the experiment 1 was used semen of one fertily ram and 67 ewes with synchronized estrus. The females were randomly distributed among two experimental groups: inseminated with frozen semen (SC1) or frozen and in vitro capacitated semen (SCC1). The ewes were submitted to the AI with 50x106 spermatozoa, 56 (SC1) or 60 (SCC1) hours, respectively, after retreat of the intra vaginal device impregnated with progesterona. In the group SCC1 the pregnancy rate was 48,39% (15/31) significantly different from the 25% (9/36) observed in the group SC1. In the experiment 2 was used one fertily ram and 100 ewes with synchronized estrus, distributed randomly among three groups: inseminated with fresh semen (SF2), 100 x 106 spermatozoa, SC2, 100 x 106 frozen spermatozoa and SCC2, 50 x 106 frozen and in vitro capacited spermatozoa. The moment of the laparoscopic AI was the same as used in the experiment 1: 56 (SF2 and SC2) or 60 (SCC2) hours, respectively, after retreat of the intra vaginal device impregnated with progesterona. The observed pregnancy rates were similar among the experimental groups: SF2 60,9% (25/41), SC2 56,70% (17/30) and SCC2 44,90% (13/29). Our experiments showed the ability of frozen/thawed and in vitro capacitated ovine spermatozoa to in vivo fertilize and promote the development of pregancies. In conclusion, itis possible to use 50x106 frozen/thawed and in vitro capacited spermatozoa for ovine laparoscopic AI.

Made available in DSpace on 2014-08-20T14:37:58Z (GMT). No. of bitstreams: 1 dissertacao_gissele_rambo.pdf: 235931 bytes, checksum: a4e2ca4dc38eed3295f04e66a374e019 (MD5) Previous issue date: 2008-11-24 / The evaluation of the efficiency of semen cryopreservation is critical to make the use of frozen semen feasible in artificial insemination programs in swine. This study compared the efficiency of two non-penetrating cryoprotectants (dimetilacetamide-DMA or glycerol) on parameters of post-thawing semen quality and in vitro fertility with frozen swine semen. The sperm-rich fractions of 28 ejaculates from four boars were frozen with either DMA or glycerol. The efficiency of semen freezing was evaluated through parameters of post-thawing semen quality and in vitro penetration (IVP) of swine oocytes and embryo production. For samples frozen with DMA, sperm motility (38.1%) and membrane integrity (39.9%) were greater (P < 0.05) than those for glycerol (21.9% and 13.0%, respectively). Both the IVP rate and the number of spermatozoa per oocyte were greater (P < 0.05) for DMA (27.9% and 29.2, respectively) than for glycerol (13.6% and 20.7, respectively). The cleavage rate with DMA and glycerol samples (13.0% and 15.6%, respectively) were similar (P > 0.05). The embryo development rate did not differ (P < 0.05) for DMA (15.8%) and glycerol (22.0%). Therefore, when compared to glycerol, DMA was associated with improved post-thawing semen quality and in vitro fertility. / A avaliação da eficiência da criopreservação do sêmen é uma importante ferramenta para viabilizar o uso de sêmen congelado na inseminação artificial em suínos. Um experimento foi realizado a fim de identificar qual crioprotetor interno (dimetilacetamida-DMA ou glicerol) seria associado com melhores indicadores de qualidade seminal pós-descongelamento e fertilidade in vitro com sêmen suíno congelado. A fração espermática rica em espermatozóides de 28 ejaculados provenientes de quatro machos foi congelada com DMA ou glicerol. Para estimar o sucesso da criopreservação do sêmen foram utilizados parâmetros de qualidade seminal pós-descongelamento, teste de penetração in vitro (TPIV) de ovócitos suínos e produção in vitro de embriões. Para amostras congeladas com DMA, a motilidade (38,1%) e a integridade da membrana espermática (39,9%) foram superiores (P < 0,05) às observadas com glicerol (21,9% e 13,0%, respectivamente). A taxa de TPIV e o número de espermatozóides por ovócito também foram superiores (P < 0,05) para a DMA (27,9% e 29,2, respectivamente) do que para o glicerol (13,6% e 20,7, respectivamente). A taxa de clivagem alcançada com a DMA (13,0%) foi similar (P > 0,05) à obtida com glicerol (15,6%). A taxa de desenvolvimento embrionário não diferiu (P > 0,05) entre DMA e glicerol (15,8% e 22,0%, respectivamente). Portanto, considerando o conjunto de todos os testes, em comparação com o glicerol, a DMA foi associada com melhores indicadores de qualidade seminal e fertilidade in vitro.

Made available in DSpace on 2014-08-20T13:32:49Z (GMT). No. of bitstreams: 1 tese_ivan_bianchi.pdf: 495717 bytes, checksum: 66978c47d9c193a45f85b5cad5be6c3f (MD5) Previous issue date: 2007-02-27 / Although boar semen is available in the frozen format since 1975, its use has been restricted to very specific situations for many reasons: it requires spermatozoa concentration per dose twice to three times higher than that for cooled semen; semen processing is labor intensive; and farrowing rate and litter size are reduced. Thus, most of the artificial inseminations in swine are performed at the day of semen collection or at most at the following day, using liquid semen conditioned between 15 and 18 ºC. The aims of this thesis were: to evaluate distinct extenders for cooling semen, methods for freezing, centrifugation temperatures, the use of amides as penetrating cryoprotectants and of low density lipoprotein as nonpenetrating cryoprotectants, and the presence of specific protein factors in seminal plasma in the results that could be associated with boar semen freezability. Five experiments have been executed: four with evaluations in vitro (motility and cell membrane integrity); and one with fertilization in vivo. The control treatment was the freezing with glycerol at 3% concentration. The semen processing method that provide more efficient results consisted of semen cooling during 120 min up to a centrifugation temperature of 15 °C. We also identified a 26 kDa factor in the seminal plasma that is associated with maintenance of the integrity of the sperm cell membrane post-thawing. Additionally, parameters of semen quality in vitro with the use of dimetilacetamide at 5% were better than those observed with the most used penetrating cryoprotectant (glycerol 3%) as control, although no difference between those cryoprotectants was observed in vivo. This study demonstrated the association of components in the seminal plasma with the sperm quality, and presenting an alternative protocol of semen freezing-thawed boar semen based in the use of dimetilacetamide at 5%. / Apesar do sêmen suíno congelado estar disponível comercialmente deste 1975, o seu uso tem ocorrido somente em ocasiões específicas, pois, em relação ao uso de sêmen refrigerado, requer duas a três vezes maior número de espermatozóides por dose, o processamento do sêmen é trabalhoso, o tamanho da leitegada é diminuído em um a três leitões por parto e a taxa de parição é menor. Dessa forma, a grande maioria das inseminações artificiais nessa espécie utiliza sêmen diluído e acondicionado no estado líquido entre 15 e 18 ºC. Os objetivos desta tese foram: avaliar diferentes diluidores de resfriamento, metodologias de congelamento, temperaturas de centrifugação, uso de crioprotetores intracelulares a base de amidas e extracelulares baseados em lipoproteína de baixa densidade, além do estudo de fatores protéicos presentes no plasma seminal nos resultados de avaliações in vitro e in vivo de sêmen suíno congelado-descongelado. Foram executados cinco experimentos com avaliações da qualidade do sêmen congeladodescongelado, quatro experimentos com avaliações in vitro (motilidade e integridade de membrana) e um experimento com fertilização in vivo. O tratamento utilizado como controle foi o congelamento com glicerol na concentração de 3%. A melhor curva de resfriamento após a coleta até 15 °C, foi atingida com o tempo de 120 min. Foi identificado um fator de 26 kDa no plasma seminal, cuja ausência proporcionou melhores resultados de integridade de membrana plasmática após o descongelamento. O uso do crioprotetor intracelular dimetilacetamida na concentração de 5%, proporcionou nas avaliações in vitro, resultados superiores ao tratamento controle (glicerol 3%), não diferindo na avaliação in vivo. O presente estudo demonstrou a relação de componentes do plasma seminal com a qualidade espermática, além de apresentar um novo protocolo de congelamentodescongelamento de sêmen suíno baseado no uso de dimetilacetamida 5%.

Abstract The main goal of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatment is a healthy mother and a healthy child. The most important complication following IVF/ICSI arises from the increased risk of multiple pregnancies. An elective single embryo transfer (eSET) with the freezing of spare embryos and subsequent treatment with frozen embryo transfer (FET) is the only way to avoid this complication. For this reason, the number of children born after FET is steadily rising. The aim of this study was to provide more detailed evidence on the safety of FET, particularly focusing on serum hormone profiles during the first trimester weeks of singleton pregnancies after IVF/ICSI fresh embryo transfer (ET), after FET during a natural menstrual cycle, and after spontaneous conception. Another part of this study compared the perinatal outcomes, congenital anomalies (CAs), and morbidity of singletons born after FET and IVF/ICSI fresh ET. The reference group was those born after spontaneously conceived (SC) pregnancies. In the clinical prospective study, the maternal serum estradiol and progesterone levels in pregnancies after fresh ET (n=39) were higher during early pregnancy weeks than in FET (n=30) and SC pregnancies (n=41), while the hormonal profiles after FET did not differ from SC pregnancies. In the large register study, FET children (n=1830) were found to have a reduced risk for adverse perinatal outcomes, such as preterm birth, a low birthweight, and being small for their gestational age compared with children born after fresh ET (n=2942). However, FET children have an increased risk for being large for their gestational age. The major CAs and morbidity until three years of age did not differ between groups. When compared with SC children (n =31 243), the perinatal outcome was worse and the rates of CAs and morbidity were higher in FET children. The FET cycle seemed to provide a better physiological environment for early fetal development than fresh ET. Further, FET protects against some of the adverse perinatal outcomes of children when compared with fresh ET, but not when it comes to the major CAs and early somatic health. This study provides further evidence of the safety of FET in comparison with fresh ET. This information should further encourage clinicians to implement eSET combined with cryopreservation in their IVF/ICSI program. / Tiivistelmä Koeputkihedelmöityshoidon (in vitro fertilization, IVF ja intracytoplasmic sperm injection, ICSI) tavoitteena on terve äiti ja terve lapsi. Monisikiöraskaus on hoidon komplikaatio, koska siihen liittyy selkeästi kohonnut riski äidille ja lapselle. Yhden alkion siirto, jäljelle jääneiden alkioiden pakastus ja myöhemmin tehtävä pakastetun alkion siirto (PAS) ovat lisänneet IVF/ICSI-hoitojen turvallisuutta ja tehokkuutta. Täten PAS:sta syntyneiden lasten määrä kasvaa. Tutkimuksen tavoitteena on lisätä PAS-hoitojen turvallisuutta tarkastelemalla veren steroidihormonien muutoksia alkuraskaudessa naisilta, jotka olivat tulleet raskaiksi IVF/ICSI-tuorealkion siirroista, luonnollisen kuukautiskierron aikana tehdystä PAS:sta ja luonnollisesti. Lisäksi tutkimuksessa verrattiin PAS- ja IVF/ICSI-tuorealkion siirrosta alkunsa saaneiden lasten terveyttä kolmeen ikävuoteen asti. Viiteryhmän muodostivat luonnollisesti alkunsa saaneet lapset. Kliinisessä prospektiivisessa tutkimuksessa havaittiin naisilla, joilla oli tuorealkion siirrosta alkanut raskaus (n=39), merkittävästi koholla olevat seerumin estradioli- ja progesteronipitoisuudet 7-8 raskausviikolle asti verrattuna naisiin, joilla raskaudet olivat alkaneet PAS:sta (n=30) tai luonnollisesti (n=41). Vastaavasti PAS-raskauksissa hormonipitoisuudet eivät eronneet merkittävästi luonnolliseen raskauteen verrattuna. Laajassa rekisteritutkimuksessa havaittiin PAS-lapsilla (n=1830) olevan pienempi riski ennenaikaisuuteen ja pienipainoisuuteen kuin tuorealkiolapsilla (n=2942). Kuitenkin PAS-lapsilla oli lisääntynyt riski syntyä isokokoisina raskausviikkoihin nähden. Synnynnäisten epämuodostumien ja eri sairauksien esiintyvyyksissä ei ollut eroja. Luonnollisesti alkunsa saaneisiin lapsiin (n= 31 243) verrattaessa, PAS-lapsilla oli vastasyntyneisyyskaudelta lähtien enemmän terveyteen liittyviä ongelmia. Tutkimus osoitti PAS-raskaudessa sikiön kehittyvän alkuviikkoina luonnollisemmassa ympäristössä kuin tuorealkion siirtoraskaudessa. Vaikka suurin osa PAS- ja tuorealkiolapsista oli terveitä, tuorealkiolapsilla oli vastasyntyneisyyskaudella enemmän ongelmia kuin PAS-lapsilla. Muita terveyseroja lasten välillä ei todettu. Tutkimus antaa lisänäyttöä PAS hoidon turvallisuudesta. Alkion pakastamisella voidaan välttää koeputkihedelmöityshoidon riskejä pyrkimällä mahdollisimman usein yhden alkion siirtoon.

The development of alternative binder systems for tungsten carbide (WC) based cemented carbides has again become of relevance due to possible changes in EU regulations regarding the use of Cobalt (Co). A framework for the ICME (Integrated Computational Materials Engineering) based Materials Design is presented to accelerate the development of alternative binder systems. Part one of this work deals with the design of the cemented carbide composite hardness. It has been shown that the intrinsic binder hardness is comparable to a bulk metal alloy and that based on the binder solubilities a solid solution strengthening model developed in this work can be employed. Using a method presented in this work the non-equilibrium, frozen-in binder solubilities can be obtained. Both the design of the binder phase and composite hardness is presented based on a general Materials Design approach. Part two deals with a multiscale approach to model the surface gradient formation. The experimentally missing data on liquid binder diffusion has been calculated using AIMD (Ab initio Molecular Dynamics). The diffusion through the liquid cemented carbide binder has to be reduced to an effective diffusion value due to the solid carbides acting as obstacles that increase the diffusion path. The geometrical reduction of the diffusion has been investigated experimentally using the SIMS (secondary ion mass spectroscopy) technique in WC-Nickel-58Nickel diffusion couples. The geometrical contribution of the so-called labyrinth factor has been proven by the combination of the experiments and in conjunction with DICTRA simulations using the precise liquid AIMD diffusivities. Unfortunately, despite the improved kinetic database and the geometrical diffusion reduction, the surface gradient formation cannot be explained satisfactory in complex cemented carbide grades. Additional, but so far unidentified, contributions have to be considered to predict the surface gradient thickness. / <p>QC 20170919</p>

La ventilation joue un rôle important dans le confort thermique des occupants d'un bâtiment en climat chaud, en contribuant au rafraîchissement de l'air qui les entoure. Qu'elle soit mécanique ou naturelle, la ventilation doit être maîtrisée pour ne pas gêner l'occupant et respecter des normes ou réglementations en vigueur. Ces gênes sont liées à des vitesses d'air ou à une intensité turbulente trop élevée. Les concepteurs doivent alors faire appel à l'outil numérique pour une prédiction fine des écoulements d'air. La simulation de configurations à l'échelle du bâtiment peut se faire par une approche moyennée des équations de Navier-Stokes en complément d'un modèle de turbulence. Ces simulations sont utilisées par les chercheurs comme des outils de dimensionnement, ou encore, d'optimisation des composants de ventilation. De plus, la forme des bouches de ventilation peut contribuer passivement à l'optimisation de certains phénomènes aérauliques. L'amélioration de ces formes peut ainsi se faire par l'utilisation de méthodes d'optimisation de forme. L'optimisation topologique par ajout de matière permet de trouver des formes pour optimiser des fonctionnelles objectifs définies sur le fluide ou sur ses frontières. C'est sur cette méthode que ces travaux de thèse se concentrent pour proposer un outil de contrôle des écoulements d'air dans le bâtiment par la recherche de formes optimales de bouches de ventilation. Ces travaux de thèse proposent une contribution à l'optimisation topologique d'écoulements turbulents dans le bâtiment. Dans un premier temps, la méthode par ajout de matière est appliquée pour minimiser les pertes de charge dans une conduite d'aération en forme de Té. Le modèle adjoint développé est soumis à l'hypothèse de turbulence gelée. Dans un second temps le modèle adjoint complet est proposé pour le modèle de turbulence standard k-epsilon pour la réduction des pertes de charge d'une part et de l'intensité turbulente d'autre part. Enfin, ces outils sont appliqués à l'optimisation de forme de bouches de ventilation. Les résultats montrent ainsi un bon potentiel de l'optimisation topologique par ajout de matière pour l'orientation des écoulements d'air mais ne garantissent pas la maîtrise des vitesses d'air dans la pièce. De plus, la minimisation de l'intensité turbulente grâce à l'approche complète développée a contribué à la réduction du taux d'insatisfaction lié à une intensité turbulente trop élevée dans la pièce. / Ventilation plays a key role in thermal comfort of building's occupants in hot climates by refreshing air surrounding them. Mechanical or natural ventilation must be controlled for two reasons: do not disturb the bulding's occupants and comply with the regulations in force. Discomfort is linked to too high air velocities or turbulent intensity. Designers can use the numerical tools for a finer prediction of airflow. The simulation of configurations at the building scale can be done using averaged Navier-Stokes equations approach in addition to a turbulence model. These simulations are used by researchers as sizing tools or for the optimization of ventilation components. In addition, the shape of the ventilation nozzle can passively contributes to the optimization of some aeraulics phenomena. The improvement of these ventilation components can be achieved by the use of shape optimization methods. Topological optimization by addition of material makes it possible for the optimization of cost functions defined on the fluid or on its boundaries. The main objective of this manuscript is to propose a tool to control airflows in building by the search for optimal shape of ventilation nozzle. This work proposes a contribution to the topological optimization of turbulent flows in buildings. In a first step, topological optimization by adding material is applied to minimize pressure losses in a T-shaped pipe. The developed model is subjected to the hypothesis of the frozen turbulence. In a second step, the complete adjoint model is proposed for the standard turbulence model k-epsilon for the minimization of the total pressure losses on the one hand and the turbulent intensity on the other hand. Finally, these tools are applied to the shape optimization of ventilation nozzle. The results of topological optimization by adding virtual material show good potential for the orientation of the airflows but does not guarantee the control of the air velocities in the room. Moreover, the minimization of turbulent intensity through the complete approach contributed to the reduction of the dissatisfaction rate due to excessive turbulent intensity in the room.

Orientadores: Marcelo Cristianini, Pedro Esteves Duarte Augusto / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-24T10:15:18Z (GMT). No. of bitstreams: 1 Leite_ThiagoSoares_M.pdf: 1645658 bytes, checksum: 5cef9e21cdc929b63d32c29376a6edbc (MD5) Previous issue date: 2014 / Resumo: O Brasil é o maior produtor mundial de laranja, sendo que a maior parte desta produção é destinada a fabricação do suco concentrado congelado (Frozen concentrated Orange Juice - FCOJ). Devido ao seu grande volume de exportação e sua alta consistência (viscosidade aparente), o conhecimento de suas propriedades reológicas se torna necessária para um melhor dimensionamento de equipamentos e processos. Na homogeneização a alta pressão (HAP), uma tecnologia de processamento não térmica, o produto é pressurizado e forçado a passar por um pequeno orifício aumentando drasticamente sua velocidade, fazendo a pressão diminuir para a atmosférica, causando forte cisalhamento e cavitação. Estes fenômenos causam alteração na estrutura de células e biopolímeros, impactando no tamanho das partículas e na maneira como se interagem, alterando assim, as características reológicas do produto. O presente trabalho se baseou na utilização desta tecnologia em FCOJ visando diminuição da sua consistência, e alteração de demais comportamentos reológicos, para gerar uma economia de energia em diversas operações unitárias como bombeamento, congelamento, transporte e estocagem. Reduções mesmo que pequenas na consistência possibilitam grande economia de energia devido aos grandes volumes de suco processado no Brasil. Este trabalho teve como objetivo avaliar a influência da alta pressão de homogeneização (HAP) no comportamento reológico em estado estacionário (independente e dependente do tempo). Foram avaliados também, a energia de ativação de Arrhenius, comportamento reológico dinâmico (viscoelasticidade), distribuição de tamanho de partículas, microestrutura e cor do suco concentrado, bem como a estabilidade à sedimentação, turbidez e cor do produto reconstituído. Também foi verificada a influência do numero de ciclos de homogeneização nos comportamentos reológicos (estado estacionário) e tamanho de partícula do suco de laranja concentrado. A consistência do FCOJ foi reduzida com o aumento de pressão no processamento de HAP. Para processos a 150 MPa a viscosidade aparente reduziu para cerca de metade do valor original, a tixotropia e viscoelasticidade também tiveram suas magnitudes reduzidas. A energia de ativação de Arrhenius teve seu valor aumentado com a utilização de HAP, indicando que pequenas variações de temperatura acarretam em variações significativas nos valores de consistência. O tamanho de partículas foi reduzido, bem como no perfil de distribuição das mesmas. Houve um aumento na proporção total de partículas pequenas em relação às partículas maiores. Estas mudanças foram possíveis de perceber pela microestrutura observada com microscópio óptico. As cores dos produtos concentrado ou diluído não apresentaram alterações devido à pressão. A HAP não praticamente não reduziu a viscosidade do suco diludo (RTD). Nenhum dos parâmetros estudados apresentou mudanças devido ao tempo de estocagem. O comportamento da sedimentação de polpa também não sofreu alterações com a HAP. Os múltiplos ciclos de HAP a baixas pressões apresentaram ser uma alternativa ao ciclo único com pressão elevada / Abstract: Brazil is the world's largest orange producer, most of the production being intended for the manufacture of frozen concentrated orange juice (FCOJ). Due to the large export volume and high consistency (apparent viscosity) of FCOJ, knowledge of its rheological properties becomes necessary for a better design of the equipments and processes. In high-pressure homogenization (HAP), a non-thermal processing technology, the product is pressurized and forced through a small gap that dramatically increases its speed, followed by a sudden drop to atmospheric pressure, causing high shear stress and cavitation. These phenomena are able to change the structure of cells and biopolymers, impacting on the particle size and the way they interact, thus changing the rheological characteristics. In the present study this technology was used aiming at decreasing the consistency and other rheological properties. Even small reductions in viscosity can result in great energy savings in various unit operations, such as pumping, given the large volume of juice processed in Brazil. The objective of this work was to evaluate the influence of high pressure homogenization on the rheological steady-state behaviour (time independent and time dependent properties), Arhenius activation energy, dynamic rheological behaviour (viscoelasticity), particle size distribution, microstructure and colour of FCOJ, as well as the pulp sedimentation stability of the reconstituted product, the turbidity and colour were also evaluated. The influence of the number of HPH cycles, on rheological behaviour (steady-state) e on particle size distribution of FCOJ was also verified. HPH decreased the consistency of FCOJ as the pressure increased from 0 to 150MPa. At 150MPa the apparent viscosity was decreased to approximately half its original value. The thixotropy and viscoelasticity of the concentrated juice were also reduced during HPH, and the value of the Arhenius activation energy had its value increased, indicating that a minor change in temperature produces a significant change in consistency. The particle size was reduced, and the particle distribution changed, showing a higher ratio of small particles over larger ones. These changes could be observed from the microstructure. The FCOJ or diluted product showed no difference in colour, neither due to affect by the homogenization nor for the storage time. HPH slighty decreased the viscosity of the RTD-juice. None of the above mentioned parameters changed during the storage time. The pulp sedimentation behaviour was not affected by HPH. Multiple HPH cycles at lower pressures are an alternative to a single HPH at higher pressure / Mestrado / Tecnologia de Alimentos / Mestre em Tecnologia de Alimentos

The dissertation deals with the state of the relations between the Organisation for Security and Cooperation in Europe and the Russian Federation. The main questions to be addressed are: "Has the Russian attitude towards the OSCE changed? How has Russia dealt with the OSCE in the last years? Do the OSCE security commitments play any role in the formation of the Russian foreign policy?" To answer these questions different approaches from international relations theories have been used, but especially, those that better reflect the importance of national constrains in foreign affairs. The formation of national interests is therefore, a key element to understand and assess the evolution of the Russian foreign policy and, subsequently, the evolution of the OSCE- Russia relations. A case of study is included to show better how Russian policies upon the OSCE have evolved from a positive engagement towards scepticism about the future of Russia within the Organisation. 1

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