Dissertations / Theses: 'Fase napo'

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Cabrero, i. Miret Ferran. "Omaguas, cataclismo amazónico." Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/284977.

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L'objectiu d'aquesta tesi és comprendre el passat amazònic i especialment la suposada nació omagua per poder avançar investigacions futures en arqueologia de camp. Els/les suposats/des omagues varen ser un dels majors grups precolombins de l'Amazònia. Haurien dominat el curs mitjà del riu Amazones, el curs mitjà del riu Napo, i la confluència d'aquest riu amb el Coca, ja a la selva de muntaña. En arqueologia se'ls ha vinculat amb la Fase policroma Amazònica, concretament amb la Subtradició Miracanguera (després inserida a la Guarita), i en especial amb la Fase Napo. Fonts etnohistòriques els citen com a bons canoers, amb una flota fluvial que els permetia dominar les principals xarxes d'intercanvi; amb característiques similars com la deformació cranial, l'ús de vestimenta de cotó amb dibuixos geomètrics multicolors, arracades, anells de nas, i pitreres d'or, l'ús d'armes com la llançadora de javelina, la “macana”, escuts, grans caps polítics i tinença d'esclaus. Tot això fa pensar que tenien una estructura social que podria associar-se a la categoria evolucionista de “cacicazgue”, amb cacics o caps el poder polític dels quals abastaria més d'un poblat. L'esplendor d'aquesta suposada nació decau amb la colonització europea, incloent baixada poblacional a causa d’epidèmies i de l' esclavisme, i amb l’homogeneïtzació cultural per mitjà de les reduccions religioses. Si bé en els segles XIX i XX sembla que hagin de desaparèixer, a finals d'aquest i principis del segle XXI processos d’etnogènesi fan renéixer certa identitat cultural comuna per al reclam de drets col·lectius.
El objetivo de esta tesis es comprender el pasado amazónico y en especial la supuesta nación omagua para poder avanzar investigaciones futuras en arqueología de campo. Los/as supuestos/as omaguas fueron uno de los mayores grupos precolombinos de la Amazonia. Habrían dominado el curso medio del rio Amazonas, el curso medio del rio Napo, y la confluencia de este rio con el Coca, ya en ceja de selva. En arqueología se los ha vinculado con la Fase Polícroma Amazónica, concretamente con la Subtradición Miracanguera (luego incorporada a la Guarita), y en especial con la Fase Napo. Fuentes etnohistóricas los citan como buenos canoeros, con una flota fluvial que les permitía dominar las principales redes de intercambio de la zona; con características similares como la deformación craneal, el uso de vestimenta de algodón con dibujos geométricos multicolores, pendientes, narigueras, y pecheras de oro, el uso de armas como la estólica y la macana, escudos, grandes jefes y tenencia de esclavos. Todo ello hace pensar que tenían una estructura social que podría asociarse a la categoría evolucionista de “cacicazgo”, con caciques o jefes cuyo poder político abarcaría más de un poblado. El esplendor de esta supuesta nación decae con la colonización europea, incluyendo bajada poblacional debido a epidemias y al esclavismo, y homogeneización cultural por medio de las reducciones religiosas. Si bien en los siglos XIX y XX parece que vayan a desaparecer, a finales de éste y principios del siglo XXI procesos de etnogénesis hacen renacer cierta identidad cultural común para el reclamo de derechos colectivos.
The aim of this thesis is to understand the Amazonian past and especially the alleged omagua nation so to advance future research in field archeology. The alleged Omaguas were one of the largest pre-Columbian Amazonian groups. They would have controled the middle reaches of the Amazon River, the middle reaches of the Napo River, and the confluence of this river with Coca River, in the mountain jungle. In archaeology they have been linked with the Amazonian Polychrome Tradition, mainly with the Miracanguera Subtradition (later under the Guarita Subtradition), and especially with the Napo Phase. Ethnohistorical sources cite them as good canoeists, with a river fleet that allowed them to dominate the major exchange networks; with similar characteristics such as cranial deformation, wearing cotton dresses with geometric and multicolored designs, earrings, nose rings and gold breastplates, the use of weapons such as the spear-thrower and baton, and shields, having big chiefs and owning slaves. This leads to the assumption that they had a social structure that could be associated with the evolutionary status of "chiefdom" with caciques or chiefs whose political power would cover more than one village. The splendor of this alleged nation decays with European colonization, including population decline due to epidemics and slavery, and due to cultural homogenization through religious reductions. Although in the nineteenth and twentieth centuries they seem likely to disappear, by the end of last century and early twenty-first century ethnogenesis processes make rebirth some common cultural identity for claiming collective rights.

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Mateus, Crislene. "Radônio como indicador de contaminação ambiental por hidrocarbonetos em fase livre." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-25072016-130633/.

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As áreas contaminadas por NAPL (Non-Aqueous Phase-Liquids ou fase líquida não aquosa ou ainda fase livre) podem causar riscos à saúde humana e aos ecossistemas, restrições para o desenvolvimento urbano e diminuição do valor imobiliário das propriedades. Este trabalho utilizou o gás radônio como um indicador para a análise de gás subsuperficial do solo, uma vez que este gás nobre apresenta boa solubilidade em uma ampla gama de NAPL, sendo parcialmente retido na contaminação NAPL. Portanto, uma diminuição da atividade de gás radônio no solo contaminado pode ser esperada, devido à elevada capacidade de particionamento do radônio em NAPL, o que permite que o NAPL retenha uma parte do radônio anteriormente disponível nos poros do solo. O levantamento foi realizado em uma indústria abandonada, contaminada por NAPL pouco volátil, localizada na zona sudeste da cidade de São Paulo, entre junho de 2014 e maio de 2015. A concentração de radônio foi avaliada pela metodologia de detecção passiva com detectores sólidos de traços nucleares (SSNTD) tipo CR-39 em dez estações de monitoramento instaladas na área contaminada investigada e nomeadas de A até J. A média das concentrações de atividade de radônio para as oito estações de monitoramento em locais supostamente não contaminados variou de (22 ± 4) kBq.m-3 a (39 ± 4) kBq.m-3. Para as duas estações de monitoramento supostas como locais contaminados, as concentrações de radônio foram (1,4 ± 0,4) kBq.m-3 e (13 ± 9) kBq.m-3. Os resultados demonstraram que o método utilizado foi consistente com as técnicas convencionais de investigação ambiental para a maioria das estações de monitoramento em diferentes estações do ano. Resultados obtidos com CR-39 variam ao longo dos períodos de exposição, devido à sazonalidade. Não foi observada relação entre as oscilações das concentrações de atividade de radônio e o volume de chuva acumulada nos diferentes períodos de exposição dos detectores CR-39. As menores concentrações de atividade do 222Rn ocorreram nas estações de monitoramento G e H e verificou-se por espectrometria gama, que a baixa atividade não está relacionada à concentração de atividade de seu pai 226Ra na série do decaimento radioativo do 238U, reforçando a teoria de retenção do gás radônio nos locais contaminados por NAPL. Resultados da etapa de remediação comprovaram que a técnica utilizada neste trabalho foi mais eficiente que as técnicas convencionais de investigação ambiental, especialmente para as estações de monitoramento D e G na área contaminada investigada.
Contaminated sites by NAPL (Non-Aqueous Phase-Liquids) may lead to safety risks to human health and to ecosystems, restrictions to urban development and decrease of real estate value. This work used the radon gas as an indicator for the analysis of subsurface soil gas, once this noble gas presents good solubility in a wide range of NAPL, being partially retained in the NAPL contamination. Therefore, a decrease of the activity of radon in the contaminated soil gas can be expected, due to the high capacity of partitioning of radon in NAPL, which allows that the NAPL retain part of the radon previously available in the soil pores. The survey was carried out at a disused industry, contaminated by low volatile NAPL, located at southeast of São Paulo city, from June/14 to May/15. Radon was evaluated by passive detection methodology with CR-39 solid state nuclear track detectors (SSNTD) in ten monitoring stations installed in the contaminated area investigated and named \"A\" to \"J\". Radon concentrations average for the eight monitoring stations at non-contaminated locations varied from (22 ± 4) kBq.m-3 to (39 ± 4) kBq.m-3. For the two monitoring stations assumed as contaminated locations, radon concentrations average were (1.4 ± 0.4) kBq.m-3 and (13 ± 9) kBq.m-3. The results have shown good agreement between the used method and the conventional environmental investigation techniques, for the majority of the monitoring stations in different seasons. Results obtained with CR-39 detectors varied over the exposure time due to the different seasons. No relation was observed between radon activity concentrations and rain volume accumulated over the different CR-39 exposure times. The lowest 222Rn activity concentrations occurred in G and H monitoring stations, also verifying by gamma-ray spectrometry, that the low activities are not related to the activity concentration of its father 226Ra from the 238U decay chain, reinforcing the theory that radon gas is retained in sites where NAPL contamination is present. Results obtained during environmental remediation proved that the methodology employed in this study was more efficient than the conventional investigation techniques, specially for the D and G monitoring stations to the investigated site.

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Moreau, Luc. "Les papillomes inverses naso-sinusiens : a propos de 38 observations." Lille 2, 1990. http://www.theses.fr/1990LIL2M152.

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Sadurní, Gràcia Núria. "Estudi de la formació de nano-emulsions de fase externa aquosa i solubilització de fàrmacs lipòfils." Doctoral thesis, Universitat de Barcelona, 2006. http://hdl.handle.net/10803/1610.

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Les nano-emulsions són emulsions amb una mida de gota molt petita i uniforme, generalment, en l'interval comprés entre els 20 i els 200nm. La seva mida característica fa que tinguin una elevada estabilitat cinètica, enfront la sedimentació o el cremat, i els confereix un aspecte transparent o translúcid. Aquest tipus de dispersions col·loïdals requereixen d'energia per a la seva formació, que pot provenir de fonts externes com ara homogeneïtzadors d'alta pressió, ultrasons, etc. (els anomenats mètodes d'emulsificació d'alta energia o de dispersió), o bé, de fonts internes, a partir de l'energia química del sistema (mètodes d'emulsificació de baixa energia o de condensació).
En la present tesi doctoral s'ha estudiat la formació de nano-emulsions de fase externa aquosa amb un elevat contingut en aigua mitjançant mètodes d'emulsificació de baixa energia adequades per la solubilització de fàrmacs pràcticament insolubles en aigua.
S'han format nano-emulsions O/W amb una mida de gota molt petita i uniforme (des de 14 fins a 70nm) mitjançant mètodes de baixa energia en sistemes aigua/tensioactiu(s) no iònic(s)/component(s) oliós(os) biocompatibles i adequats per a la seva utilització com a vehicles per a l'alliberació de principis actius. Tot i que s'han format nano-emulsions mitjançant diferents mètodes de baixa energia, el mètode òptim per a l'obtenció d'una mida de gota mínima per als sistemes estudiats ha estat l'addició d'aigua de manera successiva a mescles oli/tensioactiu mitjançant una agitació suau a 70ºC.
S'ha relacionat els estudis de comportament fàsic amb la mida de gota de les nano-emulsions obtingudes en els diferents sistemes estudiats. D'aquesta manera, les nano-emulsions dels sistemes aigua/Cremophor EL/Miglyol 812, aigua/Cremophor EL/Miglyol 812:oli de ricí 1:1, aigua/Cremophor EL/oli de ricí i aigua/Solutol HS15/Miglyol 812, en els quals s'ha identificat una fase de cristall líquid laminar en equilibri, tenen una mida de gota més petita que les obtingudes en els sistemes on no apareix aquest tipus de fase (aigua/Cremophor EL:Synperonic F68 1:1/Miglyol 812 i aigua/ aigua/Cremophor EL:polietilenglicol 400 1:1/Miglyol 812. Les transicions de fases amb la presència de cristall líquid laminar durant el procés d'emulsificació són un factor important per l'obtenció de nano-emulsions de mida de gota petita i uniforme.
Les nano-emulsions obtingudes presenten una elevada estabilitat cinètica. La mida de gota no ha excedit els 100nm durant el temps d'estudi experimental (superior a un any per a la majoria de sistemes estudiats). En cap de les nano-emulsions s'ha observat separació de fases durant l'estudi d'estabilitat cinètica.
S'han solubilitzat concentracions terapèutiques de lidocaïna i flurbiprofè, principis actius pràcticament insolubles en aigua, en nano-emulsions O/W amb un 90% d'aigua i diferents relacions oli/tensioactiu.
L'adequació de les nano-emulsions obtingudes com a vehicles per a l'administració de principis actius per via transdèrmica s'ha estudiat mitjançant la idoneïtat in vivo per ser aplicades sobre la pell i la permeació in vitro d'un principi actiu liposoluble, lidocaïna, solubilitzat en les nano-emulsions.
La determinació de la pèrdua transepidèrmica d'aigua i la mesura del canvi de color de la pell han posat de manifest que les nano-emulsions dels sistemes aigua/Cremophor EL/Miglyol 812 i aigua/Solutol HS15/Miglyol 812 no destrueixen l'estructura de la capa còrnia ni produeixen eritemes, de manera que, probablement, no alteren la integritat de la funció de barrera la pell.

Les velocitats de permeació, 80 a 149 micrograms/cm2h i de temps de latència de 0,17 a 0,69h obtinguts per la lidocaïna solubilitzada en les nano-emulsions dels sistemes aigua/Cremophor EL/Miglyol 812 i aigua/Solutol HS15/Miglyol 812 són molt inferiors a les obtingudes amb una formulació comercialitzada d'hidroclorur de lidocaïna.
Nano-emulsions are a type of emulsions with uniform and extremely small droplet size, in the range 20-200nm. Due to their characteristic size, nano-emulsions are optically transparent or translucent and they have high kinetic stability against creaming or sedimentation. As they are non-equilibrium systems, energy is required for their formation. The emulsification methods using mechanical energy are called high-energy or dispersion emulsification methods and those which use the chemical energy stored in the components are named low-energy or condensation emulsification methods.
The objectives of the present doctoral thesis have been to study nano-emulsion formation with biocompatible components using low-energy emulsification methods suitable for the solubilization of non-water soluble drugs.
O/W nano-emulsions with very small droplet sizes (from 14 to 70nm) have been formed in water/non-ionic surfactant/oil systems by using low-energy emulsification methods. The lowest droplet sizes and polydispersity indexes have been obtained by the emulsification method consisting of stepwise addition of water at 70ºC.
Phase transitions during emulsification involving one lamellar liquid crystalline phase seem to be a key factor to obtain nano-emulsions with a small and uniform droplet size.
Nano-emulsions show high kinetic stability: no phase separation occurred during the experimental study time (more than one year for the greater part of formulations). Moreover, droplet sizes of nano-emulsions have not exceeded 100nm during the kinetic stability study.
Solubilization of therapeutic concentrations of practically non-water soluble drugs, lidocaine and flurbiprofene, has been achieved in O/W nano-emulsions with 90 wt% of water content and different O/S ratios.
To assess the suitability of nano-emulsions as vehicles for transdermal delivery of drugs in vivo acceptability studies of formulations to be applied on the skin and in vitro permeation studies have been carried out. Stratum corneum structure has not been affected and erythema doesn't appear after application of nano-emulsions in vivo. In vitro delivery of lidocaine across the skin has been efficient with a short lag-time suggesting a potentially useful pharmaceutical application for these novel formulations.

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Petrocelli, Danilo. "Reti neurali convoluzionali per il riconoscimento facciale sul robot NAO." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.

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A partite dallo studio dell’attuale sistema di riconoscimento facciale presente sul robot NAO, questo lavoro di tesi si propone di ricercare una soluzione alternativa, basata sul riconoscimento delle caratteristiche facciali che possa essere utilizzata per estendere l’attuale sistema di riconoscimento in uso dal robot. Le soluzioni proposte per il rilevamento e successivo riconoscimento dei volti, nel robot NAO, si basano su delle librerie software pronte all’uso. In particolare il modulo di visione AlFacedetect consente di rilevare un volto ed in seguito riconoscerlo, mentre La fase di apprendimento avviene grazie al modulo Learn Face presente nel software Choregraphe, sviluppato dalla Aldebaran Robotics. Al fine di ricercare soluzioni alternative ai problemi esposti, sarà illustrato il software sviluppato e gli strumenti utilizzati in ciascuna delle fasi sopra indicate, nessuna delle quali utilizza i moduli built-in presenti nel NAO. La fase iniziale è consistita nella realizzazione dei datasets, uno per ogni caratteristica facciale considerata, dai quali si sono ricavati i diversi training set necessari per addestrare le reti neurali convoluzionali a classificare le caratteristiche facciali prese in esame. Per la fase di detection dei volti si sono utilizzati algoritmi noti in letteratura e opportunamente implementati nella libreria di Computer Vision OpenCV, adattati dinamicamente al compito da svolgere, ovvero alla caratteristica facciale da individuare. In questo modo si sono potute sfruttare appieno le potenzialità e l’efficienza delle reti neurali convoluzionali nello svolgere compiti di classificazione, riuscendo a garantire, nella fase di riconoscimento un’elevata precisione, in termini di accuratezza. La fase finale è consistita nel porting di quanto fatto sul robot NAO, in modo da effettuare la predizione di una determinata caratteristica facciale a partire da un’immagine acquisita attraverso la sua videocamera.

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Korchia, Daniel. "La polypose naso-sinusienne : intérêt de l'approche multidisciplinaire (à propos de 116 patients opérés)." Aix-Marseille 2, 1991. http://www.theses.fr/1991AIX20713.

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Astruc, François. "Les papillomes inversés naso-sinusiens : à propos de 38 cas." Montpellier 1, 1995. http://www.theses.fr/1995MON11105.

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Marques, Rafael. "Caracterização não invasiva de fase estacionária monolítica para uso em eletrocromatografia capilar e nano-cromatografia a líquido." Universidade Federal de Juiz de Fora (UFJF), 2017. https://repositorio.ufjf.br/jspui/handle/ufjf/6057.

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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Esta tese de doutorado aborda o preparo, a caracterização e a utilização de fases estacionárias monolíticas para uso em colunas de separação cromatográfica em escala capilar. As fases estacionárias foram preparadas pela polimerização do monômero 3-(metacriloxipropil)-trimetoxisilano em duas etapas envolvendo primeiramente um processo sol-gel e depois um processo de adição radicalar fotoiniciado. A fotopolimerização foi feita in situ em capilares de sílica fundida transparentes à radiação UV com 100 μm de diâmetro interno. As colunas produzidas foram aplicadas qualitativamente com sucesso na separação de cinco hidrocarbonetos policíclicos aromáticos e três hormônios esteroides, tanto por cromatografia a líquido capilar quanto por eletrocromatografia capilar em um equipamento de eletroforese capilar. A eletrocromatografia foi usada para analisar quantitativamente uma amostra de emulsão transdérmica contendo estriol e 17-β-estradiol. Como tentativa de melhorar a separação entre alguns analitos, foi feita a modificação do polímero adicionando o monômero benzil metacrilato, porém sem sucesso. As colunas foram caracterizadas com relação à sua homogeneidade física usando um microscópio óptico e um detector condutométrico sem contato capacitivamente acoplado. O detector foi usado como um scanner não invasivo deslocando-se longitudinalmente ao longo da coluna externamente ao capilar. A caracterização química do polímero foi feita através da espectroscopia de ressonância magnética nuclear no estado sólido dos núcleos de 13C e de 29Si. Foi possível propor uma estrutura para o arranjo da cadeia carbônica e o grau de substituição do grupo silil indicando a reticulação das cadeias poliméricas através da formação de dímeros e trímeros condensação de grupos alcoxisilanos.
This doctoral thesis adresses the preparation, characterization and use of monolithic stationary phases for chromatographic separation columns in capillary scale. The stationary phases were prepared by polymerizing the 3- (methacryloxypropyl) trimethoxysilane monomer in two steps involving a sol-gel process followed by a photoinitiated radical addition. The photopolymerization was carried out in UV transparent coating fused silica capillaries with 100 μm of internal diameter. The columns were applied in the qualitative separation of five polycyclic aromatic hydrocarbons and three steroid hormones, both by capillary liquid chromatography and capillary electrochromatography in a capillary electrophoresis equipment. Electrochromatography was used to quantitative analyzis of a transdermal emulsion sample containing estriol and 17-β-estradiol. In an attempt to improve the separation between some analytes, the polymer was modified by adding the benzyl methacrylate monomer, but without success. The columns were characterized with respect to their physical homogeneity using an optical microscope and a capacitively coupled contactless conductivity detector. The detector was used as a non-invasive scanner moving longitudinally along the column externally to the capillary. The chemical characterization of the polymer was done by the solid state 13C and 29Si nuclear magnetic resonance spectroscopy. It was possible to propose a carbon chain strucuture and the substitution degree of the silyl group indicating the cross-linking of the polymer chains through the formation of dimers and trimers by condensation of the alkoxysilane groups.

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Kalva-Filho, Carlos Augusto [UNESP]. "Validação de um teste específico para determinação do máximo déficit acumulado de oxigênio (MAOD) e da máxima fase estável de lactato em nado atado." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/87351.

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Os objetivos do presente trabalho de pesquisa foram validar metodologias de avaliação aeróbia e anaeróbia em nado atado. Para isso 23 nadadores (17±2 anos) foram submetidos a um teste incremental para a determinação do limiar anaeróbio (LAN), da máxima força atingida neste teste (FPTI), a dez esforços submáximos (50-95% da FPTI) para a construção da relação entre o consumo de O2 (VO2) e a intensidade (VO2-intensidade), a um esforço exaustivo a 100% da FPTI para a determinação do máximo déficit acumulado de oxigênio (MAOD), a um esforço máximo de três minutos para a determinação da força crítica (FC3MIN) e da força realizada acima da FC3MIN (W´3MIN) e ao protocolo de lactato mínimo. Todos os esforços foram realizados em nado atado e repetidos para testar a reprodutibilidade das medidas. A relação VO2-intensidade e o MAOD, apresentaram elevada reprodutibilidade. O MAOD determinado por meio de apenas um esforço máximo (MAODRED) não foi uma metodologia reprodutível quando determinada...
The main purpose this work was to validate the methodologies of assessment aerobic and anaerobic in tethered swimming. 23 swimmers (17 ± 2 years) underwent an incremental test to determine the anaerobic threshold (LAN) maximum force achieved in this test (PFGET), ten submaximal efforts (50-95% of FPTI) to build the relationship between O2 uptake (VO2) and intensity (VO2-intensity) and an exhaustive effort (100% of FPTI) to determine the maximal accumulated oxygen deficit (MAOD), an All-Out 3-min test to determine critical force (CF3MIN), work done above CF3MIN (W'3MIN) and the lactate minimum protocol. All efforts have been made in tethered swimming and repeated to test the reproducibility of the measurements. The VO2-intensity relationship and MAOD, showed high reproducibility. The MAOD determined by only one maximum effort (MAODRED) is not a reproducible when determined in tethered swimming... (Complete abstract click electronic access below)

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Kalva-Filho, Carlos Augusto. "Validação de um teste específico para determinação do máximo déficit acumulado de oxigênio (MAOD) e da máxima fase estável de lactato em nado atado /." Presidente Prudente, 2013. http://hdl.handle.net/11449/87351.

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Orientador: Marcelo Papoti
Coorientador: Alessandro Moura Zagatto
Banca: Adelino Sanches Ramos da Silva
Banca: Rômulo Araújo Fernandes
Resumo: Os objetivos do presente trabalho de pesquisa foram validar metodologias de avaliação aeróbia e anaeróbia em nado atado. Para isso 23 nadadores (17±2 anos) foram submetidos a um teste incremental para a determinação do limiar anaeróbio (LAN), da máxima força atingida neste teste (FPTI), a dez esforços submáximos (50-95% da FPTI) para a construção da relação entre o consumo de O2 (VO2) e a intensidade (VO2-intensidade), a um esforço exaustivo a 100% da FPTI para a determinação do máximo déficit acumulado de oxigênio (MAOD), a um esforço máximo de três minutos para a determinação da força crítica (FC3MIN) e da força realizada acima da FC3MIN (W'3MIN) e ao protocolo de lactato mínimo. Todos os esforços foram realizados em nado atado e repetidos para testar a reprodutibilidade das medidas. A relação VO2-intensidade e o MAOD, apresentaram elevada reprodutibilidade. O MAOD determinado por meio de apenas um esforço máximo (MAODRED) não foi uma metodologia reprodutível quando determinada... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The main purpose this work was to validate the methodologies of assessment aerobic and anaerobic in tethered swimming. 23 swimmers (17 ± 2 years) underwent an incremental test to determine the anaerobic threshold (LAN) maximum force achieved in this test (PFGET), ten submaximal efforts (50-95% of FPTI) to build the relationship between O2 uptake (VO2) and intensity (VO2-intensity) and an exhaustive effort (100% of FPTI) to determine the maximal accumulated oxygen deficit (MAOD), an All-Out 3-min test to determine critical force (CF3MIN), work done above CF3MIN (W'3MIN) and the lactate minimum protocol. All efforts have been made in tethered swimming and repeated to test the reproducibility of the measurements. The VO2-intensity relationship and MAOD, showed high reproducibility. The MAOD determined by only one maximum effort (MAODRED) is not a reproducible when determined in tethered swimming... (Complete abstract click electronic access below)
Mestre

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Bougis, Kévin. "Fluctuations et interactions en situation de nano-confinement anisotrope." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0060/document.

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La structure et les interactions qui stabilisent des empilements lamellaires lyotropes de bicouches lipidiques "poilues" (et dépourvues de charge électrique nette) dans leur état fluide sont principalement étudiées par diffusion de rayons X aux petits angles. Les empilements lamellaires sont utilisés comme matrices hôtes afin de confiner et d’encapsuler des nano-bâtonnets d’ADN qui s’auto-assemblent en différentes structures en fonction du confinement réalisé. L’objectif fixé est de comprendre l’origine des mécanismes qui sont responsables de la formation de tels assemblages supramoléculaires. Dans ce but,on s’intéresse aux mécanismes entropiques et interfaciaux, sensibles expérimentalement à la physico-chimie du système, cette dernière affectant notamment le caractère "lié"ou "non lié" des systèmes lamellaires à haute dilution. Un modèle thermodynamique est utilisé afin d’interpréter la décroissance exponentielle "classique" observée dans les profils de pression osmotique en fonction de l’hydratation, sans faire appel à la force"d’hydratation". Une transition structurale est mise en évidence, à faible hydratation,entre deux phases lamellaires "liées". Le changement structural de la bicouche est discuté en termes de couplage entre confinements vertical et latéral. La caractérisation de la matrice lamellaire hôte autorise finalement une description des organisations des bâtonnets d’ADN qui semblent directement corrélées aux propriétés physiques des bicouches, faisant ainsi apparaître quelques perspectives pour leur encapsulation au sein "d’ognons"
Structure and interactions stabilizing the lyotropic lamellar stack of (electrically-neutral)mixed "hairy" lipid bilayers in their fluid state are mainly investigated by means of small angleX-ray scattering. The lamellar stacks are used as hosts to confine and encapsulate DNA nanorods which organize themselves into different structures depending on the confinement.The challenge here is to understand the mechanisms responsible for the formation of these supramolecular assemblies. In this aim, we are interested in entropic and interfacial mechanisms which are both experimentally sensitive to the physical-chemistry of the system, changing in particular the “bound” or “unbound” character of the waters wollen systems. A thermodynamic model is then used for interpreting the “classical”exponential decay obtained in osmotic profiles as a function of hydration, without resorting to “hydration forces”. A structural transition between two different “bound” lamellar phases is brought out at low hydration. The bilayer structural changes are discussed as resulting from a coupling between lateral and vertical confinements. The lamellar host characterization finally allows a description of the DNA nanorods organizations which seem to be directly correlated to the physical properties of the bilayers, leaving some perspectives for the encapsulation inside “onions”
A estrutura e as interações, que estabilizam os empilhamentos lamelares liotrópicos dasmembranas lipídicas em seu estado fluido, são estudadas principalmente por espalhamento de raios-x a baixos ângulos. As membranas “peludas” (eletricamente neutras) são compostas de uma mistura em diversas proporções de lecitina, um fosfolipídio zwiteriônico, ede simulsol, um cotensoativo etoxilado não iônico similar a um copolímero dibloco (curto). Esses empilhamentos lamelares são utilizados como matrizes hospedeiras, com o intuito deconfinar e de encapsular nanobastões de DNA que se auto organizam em diferentes estruturas,em função do confinamento aplicado. O objetivo fixado é de compreender aorigem dos mecanismos responsáveis pela formação dessas organizações supramoleculares,não regidas pelas interações eletrostáticas. Dessa forma, nos interessamos aos mecanismos entrópicos e interfaciais, que são ligados à elasticidade membranar e às interações mais específicas que intervêm nas interfaces membrana-membrana ou DNA-membrana. Aabordagem experimental consiste em modificar os diferentes parâmetros físico-químicosda matriz hospedeira, como a hidratação do sistema, a natureza química do cotensoativo (blocos hidrofóbicos e/ou hidrofílicos) e a proporção de cotensoativo no interior da membrana.O cotensoativo tem então uma função chave para modificar os dois mecanismos,perturbando o estado “ligado” ou “não-ligado” em sistemas lamelares altamente diluídos.Um modelo termodinâmico é utilizado para interpretar o decréscimo exponencial “clássico”observado para os perfis de pressão osmótica, quando se aumenta a hidratação, semutilizar a “força de hidratação”. Uma transição estrutural é evidenciada, à baixahidratação, entre duas fases lamelares “ligadas”. A mudança estrutural da membranaé discutida graças ao acoplamento entre confinamento lateral e vertical, em analogia àconhecida transição “escova-cogumelo” induzida pelo confinamento lateral, relevante paralongos polímeros lineares funcionalizados em superfícies rígidas [10]. A caracterizaçãoda matriz lamelar hospedeira permite, finalmente, uma descrição das organizações dosbastões de DNA que parecem diretamente correlacionados com as propriedades físicasdas membranas, deixando, então, algumas perspectivas para sua encapsulação no interiorde estruturas semelhantes a ”cebolas”

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FOSSOUD, FREDERIC. "La polypose naso-sinusienne invalidante : place de l'ethmoidectomie par voie endo-nasale." Toulouse 3, 1991. http://www.theses.fr/1991TOU31518.

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Spagnuolo, Imerio. "Landmark based facial recognition in the NAO robot." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13227/.

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Lo scopo di questa tesi è permettere ad un robot umanoide (NAO) di rilevare i volti nelle immediate vicinanze e riconoscerli. Riconoscere il volto di una persona è un’abilità difficile da automatizzare, innanzitutto bisogna scomporre il problema in due differenti problemi: face detection e face recognition. Per face detection si intende quel processo attraverso cui è possibile rilevare la presenza o meno di uno o più volti all’interno di un’immagine o di un flusso di immagini. Una volta accertata la presenza di un volto è possibile passare alla fase di recognition. Tale fase viene realizzata tramite l’ausilio di un classificatore che prende in ingresso delle feature estratte dal volto identificato e restituisce il nome della persona a cui esso potrebbe appartenere con la relativa probabilità. Il sistema proposto in questa tesi è caratterizzato da una fase di rilevazione del volto realizzata attraverso la tecnica dei gradienti orientati, delle fasi di pre-processing delle immagini ed una classificazione dei volti attraverso l’implementazione di due differenti reti neurali in cascata. La prima rete è una rete neurale convoluzionale che prende in ingresso l’intera immagine e restituisce il nome della persona. La seconda rete è una rete neurale multistrato che discrimina i volti solo tra le classi su cui la prima rete fa “confusione” basandosi su determinate misure (distanza tra naso e bocca, lunghezza naso, ecc...).

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Brito, Silvio Luiz Miranda. "Síntese, caracterização e modificação superficial de nano partículas de titanato de bário produzidas pelo método Pechini." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-28052009-141416/.

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A síntese de nano partículas e a sua caracterização tem sido a grande mola propulsora do desenvolvimento de materiais nano-estruturados. Pouca atenção tem sido dedicada aos fenômenos físico-químicos relacionados às enormes superfícies intrínsecas destes materiais. Dentre eles, o titanato de bário ocupa uma posição de destaque devido ao seu grande potencial na geração de produtos de alta tecnologia. Neste estudo o BaTiO3 foi sintetizado pelo método Pechini que proporciona a geração de nanopartículas de grande uniformidade química. Contudo, o uso de cátions que formam carbonatos de alta estabilidade pode inviabilizar o uso do método. Os pós de titanato de bário preparados apresentaram elevada área de superfície específica, mas formação de fases parasitas de carbonato de bário e em algumas estequiometrias de ortotitanato de bário e carbonatos adsorvidos à superfície do titanato de bário. O estudo sistemático da química de superfície e da estrutura cristalina do material permitiu a proposta de um método de lixiviação em meio ácido onde as fases parasitas foram eliminadas e um material nanométrico de grande potencial de aplicação foi obtido com as seguintes características: fase com simetria tetragonal predominante ~95% (apesar da coexistência de fase cúbica ~5%); tamanho de cristalito ou partícula primária de 44 nm; área de superfície específica igual a 13,4 m2/g e D(BET) de 74 nm; está isento de contaminação de carbonatos ou outra fase; relação estequiométrica de Ba/Ti = 0,96 -> Ba0,98Ti1,02O3.
The synthesis and characterization of Nanoparticles has been a great topic for nanostructured materials developments. The Relationship between Physicochemical phenomena and large surface area has had a little attention. The barium titanate has a great potential of high-tech products generation. In this work, the BaTiO3 was prepared by polymeric precursor method because this method generates a great chemical uniformity in nanoparticles. However, cations that form carbonates of high-stability may compromise this method use. The barium titanate powder was prepared and showed high specific surface area, but this powder has barium carbonate and ortotitanato contamination. The systematic surface chemistry and crystal structure study suggest an acid leaching method to contaminant phases eliminated. A nanomaterial of great potential for application was obtained with the following characteristics: tetragonal phase predominant ~95% (cubic phase coexist ~5%); crystallite size of 44 nm; surface area of 13,4 m2/g and Particle size (estimated BET) of 74 nm; carbonate free; Ba/Ti = 0,96 -> Ba0,98Ti1,02O3.

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Bonnet, Jacques. "Contribution a l'etude de l'etiologie dentaire des aspergilloses naso-sinusiennes : a propos de 85 observations." Nantes, 1988. http://www.theses.fr/1988NANT105M.

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BALOUKA, JEAN BERNARD. "Les metastases naso-sinusiennes de la tumeur de grawitz : a propos de trois cas." Université Louis Pasteur (Strasbourg) (1971-2008), 1992. http://www.theses.fr/1992STR1M234.

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Granger-Veyron, Nicolas. "Aspergilloses naso-sinusiennes chez l'immunocompétent : expérience bordelaise au sujet de 62 cas." Bordeaux 2, 1999. http://www.theses.fr/1999BOR2M017.

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Favà, Figueres Vicent. "Efectos climáticos en la Península Ibérica del cambio de fase del índice SNAO en 1967." Doctoral thesis, Universitat Ramon Llull, 2019. http://hdl.handle.net/10803/667948.

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El principal objectiu d'aquesta tesi és estudiar els canvis que es van produir en la temperatura, precipitació i vent a la Península Ibèrica (PI) i que es van derivar de la brusca transició que va experimentar l'índex SNAO (Oscil·lació de l'Atlàntic Nord a l'estiu) cap a una fase positiva persistent a la fi dels anys 60 del segle XX, com a conseqüència del Rapid Global Climate Shift. Per això han estat utilitzades dades de reanàlisi de NCEP / NCAR (National Centers for Environmental Prediction / Nacional Center for Atmospheric Research) juntament amb diverses bases de dades procedents de l'observació, principalment Spain02 (temperatures a l'Espanya peninsular) i E-OBS ( temperatures i precipitació a nivell del continent europeu). S'ha implementat el mètode d'anàlisi de components principals (PCA) per al càlcul de diversos índexs atmosfèrics, i s'han aplicat diversos mètodes no paramètrics per a l'estimació de la significació estadística de tendències i correlacions (Mann-Kendall i Block Bootstrap). En síntesi aquest estudi ha contemplat diverses anàlisis regionals (influència sobre les temperatures màximes a l'Espanya Peninsular i sobre les precipitacions al NE) i diverses anàlisis a escala local (canvis en la direcció del vent en els observatoris de l'Ebre, Ourense i València i el seu impacte en les temperatures màximes) Els resultats més rellevants han estat trobats en comparar les condicions climàtiques del període 1950-1966 respecte a les dels anys 70 i principis dels 80. S'ha trobat que els valors negatius de SNAO del període 1950-1966 es van caracteritzar no només per una elevada freqüència de sistemes de baixes pressions al nord d'Europa, sinó que, per la seva disposició espacial, aquestes van influir més del que és habitual en les condicions del nord de la PI. S'han trobat quatre patrons sinòptics en què la forma en què es distribueixen al nord d'Europa les zones d'altes pressions (SNAO positiu) o les baixes pressions (SNAO negatiu), influeix directament en la classe de temps que cal esperar en al nord de la PI. A escala regional s'ha trobat que els valors negatius de SNAO dels anys 50 i 60 van estar associats en general a una disminució de la vorticitat al SW i a un augment en el NE, factors que van contribuir a fer pujar les temperatures màximes a la zona del litoral de València i del SE de la PI. Quan SNAO va canviar a valors fortament positius a partir de finals dels 60, aquest patró de vorticitats es va revertir, fent que el flux en superfície tendís a ser més marítim, el que va contribuir a la baixada de la temperatura màxima i de l'oscil·lació tèrmica diària observades a València i al litoral SE de la PI entre finals dels anys 60 i principis dels 80. Els valors negatius de SNAO dels anys 50 i 60 van estar associats, a més, a la formació d'un nucli anticiclònic sobre la Mediterrània Occidental , aïllat de la Anticicló de les Açores. Entre tots dos sistemes d'altes pressions, la PI quedava en un pantà baromètric que afavoria d'una banda la formació de baixes tèrmiques sobre el centre-est de la PI i de l'altra, l'arribada d'aire càlid i humit al NE de la PI, factor que probablement va contribuir a la formació de tempestes. En el període 1950-1966, les precipitacions al NE de la PI van mostrar correlacions significatives de signe negatiu amb SNAO, de signe contrari a l'obtingut amb les precipitacions del centre de la PI en el període 1950-2010. S'ha trobat també que en el període 1950-1966, les transicions de flux de component sud a component nord al NE de la PI van contribuir més que en qualsevol altre període a la precipitació, el que és coherent amb una major precipitació d'origen frontal en aquest període.
El principal objetivo de esta tesis es estudiar los cambios que se produjeron en la temperatura, precipitación y viento en la Península Ibérica (PI) y que se derivaron de la brusca transición que experimentó el índice SNAO (Oscilación del Atlántico Norte en verano) hacia una fase positiva persistente a finales de los años 60 del siglo XX, como consecuencia del Rapid Global Climate Shift. Para ello han sido utilizados datos de reanálisis de NCEP/NCAR (National Centers for Environmental Prediction/ Nacional Center for Atmospheric Research) junto con diversas bases de datos procedentes de la observación, principalmente Spain02 (temperaturas en la España peninsular) y E-OBS (temperaturas y precipitación a nivel del continente europeo). Se ha implementado el método de análisis de componentes principales (PCA) para el cálculo de diversos índices atmosféricos, y se han aplicado diversos métodos no paramétricos para la estimación de la significancia de tendencias y correlaciones (Mann-Kendall y Block Bootstrap). En síntesis este estudio ha contemplado diversos análisis regionales (influencia sobre las temperaturas máximas en la España Peninsular y sobre las precipitaciones en el NE) y diversos análisis a escala local (cambios en la dirección del viento en los observatorios del Ebro, Ourense y Valencia y su impacto en las temperaturas máximas) Los resultados más relevantes han sido encontrados al comparar las condiciones climáticas del periodo 1950-1966 con respecto a las de los años 70 y principios de los 80. Se ha encontrado que los valores negativos de SNAO del periodo 1950-1966 se caracterizaron no sólo por una elevada frecuencia de sistemas de bajas presiones en el norte de Europa, sino que, por su disposición espacial, éstas influyeron más de lo habitual en las condiciones del norte de la PI. Se han encontrado cuatro patrones sinópticos en los que la forma en la que se distribuyen en el norte de Europa las zonas de altas presiones (SNAO positivo) o las bajas presiones (SNAO negativo), influye directamente en la clase de tiempo que cabe esperar en el norte de la PI. A escala regional se ha encontrado que los valores negativos de SNAO de los años 50 y 60 estuvieron asociados en general a una disminución de la vorticidad en el SW y a un aumento en el NE, factores que contribuyeron a hacer subir las temperaturas máximas en la zona del litoral de Valencia y del SE de la PI. Cuando SNAO cambió a valores fuertemente positivos a partir de finales de los 60, este patrón de vorticidades se revirtió, haciendo que el flujo en superficie tendiera a ser más marítimo, lo que contribuyó a la bajada de la temperatura máxima y de la oscilación térmica diaria observadas en Valencia y en el litoral SE de la PI entre finales de los años 60 y principios de los 80. Los valores negativos de SNAO de los años 50 y 60 estuvieron asociados, además, a la formación de un núcleo anticiclónico sobre el Mediterráneo Occidental, aislado del Anticiclón de las Azores. Entre ambos sistemas de altas presiones, la PI quedaba en un pantano barométrico que favorecía por un lado la formación de bajas térmicas sobre el centro-este de la PI y por el otro, la llegada de aire cálido y húmedo al NE de la PI, factor que probablemente contribuyó a la formación de tormentas. En el periodo 1950-1966, las precipitaciones en el NE de la PI mostraron correlaciones significativas de signo negativo con SNAO, de signo contrario al obtenido con las precipitaciones del centro de la PI en el periodo 1950-2010. Se ha encontrado también que en el periodo 1950-1966, las transiciones de flujo de componente sur a componente norte en el NE de la PI contribuyeron más que en cualquier otro periodo a la precipitación, lo que es coherente con una mayor precipitación de origen frontal en este periodo.
The main objective of this thesis is to study the changes in temperature, precipitation and wind in the Iberian Peninsula (IP) that were derived from the sudden transition of the SNAO index (Summer North Atlantic Oscillation) towards a persistent positive phase in the late 60's of the twentieth century, as a result of the Rapid Global Climate Shift. To this end, NCEP / NCAR reanalysis data (National Centers for Environmental Prediction / National Center for Atmospheric Research) have been used together with several observational databases, mainly Spain02 (temperatures in mainland Spain) and E-OBS (European temperature and precipitation data). The principal component analysis (PCA) method has been implemented for the calculation of various atmospheric indices, and various nonparametric methods have been applied to estimate the significance of trends and correlations (Mann-Kendall and Block Bootstrap). In summary, this study has contemplated various regional analyses (influence on the maximum temperatures in the peninsular Spain and on rainfall in the NE) and various analyses at local scale (changes in wind direction at the Ebro, Ourense and Valencia observatories and its impact on maximum temperatures). The most relevant results have been found when comparing the climatic conditions of the period 1950-1966 with respect to those of the 70s and early 80s. It has been found that the negative values of SNAO for the period 1950-1966 were characterized not only by a high frequency of low pressure systems in northern Europe, but, because of their spatial arrangement, they influenced more than usual the conditions of northern IP. Four synoptic patterns have been found in which the way in which high pressures (positive SNAO) or low pressure areas (negative SNAO) are distributed in northern Europe, directly influences the kind of weather that can be expected in the north of the IP. On a regional scale it has been found that the negative SNAO values of the 50s and 60s were generally associated with a decrease in the vorticity in the SW and an increase in the NE, factors that contributed to raise the maximum temperatures in the area of the coast of Valencia and the SE of the IP. When SNAO changed to strongly positive values from the end of the 60s, this pattern of vorticities was reversed, resulting in an enhanced maritime flow, which contributed to the observed decrease in maximum temperatures and daily temperature range (DTR) in Valencia and in the SE coast of the IP between the end of the 60s and the beginning of the 80s. The negative SNAO index phase registered from the 50s to mid-60s were also associated with the formation of an anticyclonic nucleus on the Western Mediterranean, isolated from the Azores High. Between both high pressures systems, the IP remained in a barometric swamp that favored on the one hand the formation of thermal lows on the center-east of the IP and on the other, the arrival of warm moist air at the NE of the IP, factor that probably enhanced the formation of storms. In the period 1950-1966, rainfall in the NE of the IP showed significant correlations of negative sign with SNAO, of opposite sign to that obtained with the precipitation in the center of the IP in the period 1950-2010. It has also been found that in the period 1950-1966, the transitions from southerly to northerly flow in the NE of the IP contributed to precipitation more than in any other period, which is consistent with an enhanced frontal precipitation in this period.

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Mandel, Kristin. "Untersuchungen zum feldaktivierten Sintern und zum geschwindigkeitsabhängigen Festigkeits- und Versagensverhalten von near-nano WC-Co-Hartstoffen unter Druckbeanspruchung." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2014. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-137517.

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In dieser Arbeit wurden das feldaktivierte Sinterverhalten sowie das geschwindigkeitsabhängige Druckfestigkeitsverhalten von WC-Co-Hartstoffen mit variierenden Bindergehalten untersucht. Dazu wurde eine Herstellungsroute für kornwachstumshemmerfreie near-nanokristalline WC-Co-Hartstoffe mit der Field Assisted Sintering Technique (FAST) entwickelt und genutzt, um Materialien mit Co-Gehalten von 2 bis 12 Ma.-% zu erzeugen. Gezielte Werkstoffzustände und Probengeometrien sind durch Anpassung des Sinterprozesses herstellbar. Ausgewählte WC-Co-Materialien mit Co-Anteilen von 6 bis 12 Ma.-% wurden unter Einfluss von Beanspruchungsgeschwindigkeit, Spannungszustand und Beanspruchungshäufigkeit hinsichtlich der Druckfestigkeit und des Versagensverhaltens charakterisiert.

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Cavalcanti, Bezerra dos Santos Leonardo. "Avaliação dos espaços naso e oro-faríngeos e suas correlações com altereções dimensionais da face em pacientes admitidos no serviço de ortopedia facial da UFPE." Universidade Federal de Pernambuco, 2012. https://repositorio.ufpe.br/handle/123456789/8481.

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Made available in DSpace on 2014-06-12T23:00:19Z (GMT). No. of bitstreams: 2 arquivo8513_1.pdf: 1653631 bytes, checksum: dad331d76921481081873690505c76ac (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2012
A mastigação e a respiração constituem duas ações básicas e fundamentais na manutenção da qualidade de vida do indivíduo. As relações anatômicas e funcionais entre os sistemas respiratórios e mastigatórios são muito próximas e em algumas situações poderão estar correlacionados a uma patologia de etiologia comum, portanto, o diagnóstico de uma deformidade facial deverá levar em consideração as alterações morfológicas e funcionais de ambos os sistemas. O objetivo deste estudo foi o de investigar as possíveis correlações entre os espaços naso e oro-faríngeos e alterações das dimensões verticais, bem como o posicionamento ântero-posterior da maxila e da mandíbula. Foi realizado um estudo retrospectivo em 161 radiografias cefalométricas laterais com análise de McNamara de pacientes admitidos no Serviço de Ortopedia Facial da Universidade Federal de Pernambuco. Os dados foram avaliados pelos métodos estatísticos de Person, Spearm e Kendal todos à níveis de significância de 0,05 %. Os espaços naso e oro-faríngeos mostraram uma correlação positiva com posicionamento ântero-posterior da mandíbula e com posicionamento ântero-posterior da maxila e também com dimensão vertical da face, foi observado uma correlação negativa entre dimensão vertical da face e o posicionamento ântero-posterior da mandíbula. Concluiu-se que houve uma grande incidência de diminuição dos espaços naso-faríngeos na amostra estudada e as correlações foram estatisticamente significantes

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INSERRA, SABRINA. "L'apport de l'ethmoidectomie endonasale dans la polypose naso-sinusienne de l'asthmatique : interet, resultats sur une serie de 40 patients." Nice, 1992. http://www.theses.fr/1992NICE6544.

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Morral, Ruíz Genoveva. "Estudi de la formació de nanopartícules polimèriques obtingudes a partir de nanoemulsions de fase externa aquosa i associació d’antiinflamatoris no esteroïdals." Doctoral thesis, Universitat de Barcelona, 2011. http://hdl.handle.net/10803/83823.

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Les nano-emulsions són emulsions amb una mida de gota molt petita i uniforme, normalment compresa entre 20 i 200 nm, que poden formar-se a baixes concentracions de tensioactiu. Degut a les seves propietats específiques (mida de gota, elevada estabilitat cinètica i transparència òptica) les nano-emulsions tenen importants aplicacions en indústria química, cosmètica i farmacèutica. En aquest sentit, una de les principals aplicacions tecnològiques és la seva utilització com a medi de polimerització per a l’obtenció de nanopartícules. Les nanopartícules polimèriques poden definir-se com a sistemes col•loïdals sòlids amb un diàmetre comprès entre 10 i 1000 nm en les quals el principi actiu es pot trobar solubilitzat, atrapat, encapsulat, adsorbit o fins i tot unit a la superfície d’una matriu polimèrica que actua com a vehicle permetent l’alliberació selectiva del fàrmac en el lloc d’acció. Per tant, mitjançant la formació de nanopartícules s’aconsegueix dotar al sistema col•loïdal inicial d’una certa rigidesa morfològica que conjuntament amb la petita mida de partícula fan que aquestes composicions siguin idònies com a sistemes d’alliberació controlada de fàrmacs. D’acord amb aquestes premisses, l’objectiu principal d’aquest treball d’investigació ha estat estudiar la formació de nanopartícules polimèriques a partir de nano-emulsions de fase externa aquosa (O/W), obtingudes per mètodes d’emulsificació de baixa energia, en sistemes aigua/ tensioactiu no iònic: co-tensioactiu/ component oliós amb excipients biocompatibles i adequats per a l’administració per via parenteral i tòpica. Una de les fites més importants d’aquest treball d’investigació ha consistit en desenvolupar sistemes nanoestructurats recoberts amb polietilenglicol i biomaterials que podrien incrementar la biodisponibilitat d’aquests sistemes col•loïdals. Per tal d’assolir aquest objectiu, en una primera etapa es va estudiar la formació, caracterització i propietats de les nano-emulsions O/W i posteriorment es va procedir a l’elaboració de les nanopartícules polimèriques. En aquesta segona etapa, també es va estudiar la influència dels paràmetres de composició així com també de la temperatura i temps de polimerització en la preparació de les nanopartícules. Els sistemes de nano-emulsions i nanopartícules es van caracteritzar per Espectroscòpia de Correlació Fotònica (DLS), Microscòpia Electrònica de Transmissió (TEM), Microscòpia de Força Atòmica (AFM) i Microscòpia confocal. La formació de polímers de poliuretà i poliurea es va constatar a través de les anàlisis dels espectres obtinguts per Espectroscòpia d’Infraroig per Transformada de Fourier (FT-IR). Finalment, es va incorporar un fàrmac antiinflamatori no esteroïdal (ketoprofèn) en els sistemes esmentats i es van dur a terme estudis d’incorporació, alliberació i permeació cutània del fàrmac. Mitjançant els estudis de comportament fàsic s’han identificat regions on es formen nano-emulsions O/W amb una elevada concentració d’aigua (90% i 95% en pes) i components utilitzats per a la preparació de nanopartícules. Aquestes nano-emulsions O/W presenten una mida de gota compresa entre 13 i 42 nm, una elevada estabilitat cinètica i una baixa polidispersitat que les fa apropiades per a ser utilitzades com a sistemes d’alliberació controlada de fàrmacs i com a medi de polimerització per l’elaboració de nanopartícules polimèriques. Destacar també, que s’ha aconseguit la formació de nanopartícules de poliuretà i poliurea recobertes amb polietilenglicol i diferents biomaterials amb un diàmetre de partícula inferior a 100 nm i una baixa polidispersitat (<0,150) que presenten una elevada estabilitat cinètica, a partir de nano-emulsions obtingudes mitjançant mètodes d’emulsificació de baixa energia. Aquests sistemes serien adequats per a la vehiculització de principis actius amb una baixa solubilitat en aigua ja que es van aconseguir incorporar concentracions elevades d’un fàrmac model, ketoprofèn, amb una elevada eficiència d’associació (≥ 80 %). Per altra banda, els estudis de cessió van posar de manifest que el principi actiu es capaç d’alliberar-se completament des de les formulacions cap a una solució receptora seguint una cinètica d’ordre zero.
Nano-emulsions are emulsions optically transparent or translucent, characterized by uniform and extremely small droplet size in the range of 20-200 nm. Because of their small size, they may have high kinetic stability. Owing to these specific properties nano-emulsions have been widely used in chemical, cosmetic and pharmaceutical fields. In this regard, it is especially noteworthy their use as templates to prepare nanoparticles. Polymeric nanoparticles are solid colloidal materials of less than 1µm, in which drugs may be dissolved, entrapped or encapsulated, chemically attached to the polymers or even adsorbed to the particle surface. Due to their small size, kinetic stability and large structural variety both systems constitute a promising tool as drug carriers for targeted drug delivery. Therefore, the aims of this research have been: a) to study the formation of polymeric surface-modified nanoparticles from O/W nano-emulsions obtained by low-energy emulsification methods in water/nonionic surfactant/co-surfactant/oil systems with biocompatible excipients suitable for parenteral and topical administration and b) to incorporate a non steroidal anti-inflammatory drug in nano-emulsions and nanoparticles and to study the drug release from these colloidal systems. Nano-emulsions and nanoparticles were characterised by DLS, TEM, AFM and confocal microscopy and their stability at 25ºC was also studied. The formation of polyurethane and polyurea polymer was confirmed by FT-IR analysis. Phase behaviour studies allowed the identification of O/W nano-emulsion regions with high water content in the water/nonionic surfactant/oil and water/surfactant/co-surfactant/oil systems. These nano-emulsions possess mean diameters ranging from 13 to 42 nm, low polydispersity and good kinetic stability. These properties make them appropriate as drug delivery systems and as reaction media for the preparation of polymeric nanoparticles. Moreover, we achieved to prepare polyurethane and polyurea nanoparticles with a particle size lower than 100 nm, low polydispersity index and high kinetic stability from selected O/W nano-emulsions obtained by low-energy emulsification methods. These systems are suitable to load drugs with low water solubility. Thus, Ketoprofen, was successfully loaded into nanoparticles achieving a yield of encapsulation ≥ 80 wt %. Eventually, drug release studies demonstrate that Ketoprofen can diffuse completely from nano-emulsions and nanoparticle suspensions with drug release profiles following zero-order kinetic patterns.

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23

Matos, Margarida dos Santos Diogo Luis de. "Consolidação e reintegração cromática de revestimentos antigos - Comportamento face a cloretos." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/11052.

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Dissertação para obtenção do Grau de Mestre em Engenharia Civil Perfil Construção
Um fenómeno comum de degradação dos revestimentos antigos é a perda de coesão do sistema ligante-agregado. Quando o edifício apresenta valor histórico, a restituição da coesão é realizada através do uso de consolidantes, sendo esses produtos compatíveis com os revestimentos pré-existentes, para garantir a sua integração e durabilidade. Os consolidantes mais adequados são os inorgânicos devido à sua maior compatibilidade e durabilidade. São exemplos a água de cal e o silicato de etilo, que no entanto têm sido usados com eficácia limitada. Devido a esta baixa eficácia registada, têm surgido alternativas ao longo dos anos: as dispersões em álcool de nano-partículas de cal. Outro fenómeno que afecta os edifícios antigos é a acção dos sais solúveis. É considerada uma das principais causas de degradação, uma vez que, para além do facto das argamassas antigas serem porosas (o que facilita a acumulação de sais e de humidade), apresentam resistências mecânicas fracas, originando baixas resistências às tensões internas decorrentes da cristalização dos sais. Neste estudo, numa primeira fase, foram utilizados consolidantes nano-estruturados à base de hidróxido de cálcio, aditivado também com silicato de etilo, e soluções aquosas de hidróxido de cálcio e metacaulino. Estes consolidantes foram incorporados com pigmentos inorgânicos para avaliar a viabilidade da reintegração cromática. Na segunda fase do trabalho foram realizados ciclos de dissolução-cristalização com uma solução de cloreto de sódio, semelhante à concentração de sal da água do mar. Os consolidantes foram aplicados em provetes de revestimento de argamassa de cal aérea com uma perda simulada de coesão, obtida com um traço fraco de ligante. Realizaram-se ensaios para avaliar a eficácia dos consolidantes. Os provetes consolidados foram contaminados com cloreto de sódio e repetiram-se os ensaios, com o objectivo de aferir a resistência dos tratamentos de consolidação à acção do cloreto de sódio. Concluiu-se que os consolidantes estudados são compatíveis, eficientes, apresentam boa durabilidade e, na presença do cloreto de sódio, apresentam resistência satisfatória saindo ligeiramente prejudicados quanto à durabilidade. Em relação à adição de pigmentos, estes influenciam ligeiramente o tratamento de consolidação e a resistência ao cloreto de sódio. Este trabalho insere-se no projecto LIMECONTECH financiado pela Fundação para a Ciência e a Tecnologia.

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Hensen, Matthias [Verfasser]. "Concentrating Light: Nano-devices for spectroscopy, ultra-fast current injection and coherent energy transport / Matthias Hensen." Bielefeld : Universitätsbibliothek Bielefeld, 2016. http://d-nb.info/1105645533/34.

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25

Barros, Kleber Vânio Gomes. "Sistema de duas fases aquosas NaPA/PEG aplicado na purificação de proteases produzidas por fungos filamentosos." reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/17724.

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Tese (doutorado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Programa de Pós-Graduação em Ciências Farmacêuticas, 2014.
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O desenvolvimento de metologias que permitam a purificação de biomoléculas de interesse industral é alvo de estudo devido sua importância comercial. Foi avaliada a purificação de proteases produzidas pelos fungos isolados do Cerrado, Penicillium fellutanum e Penicillium restrictum por extração líquido-líquido em sistema de duas fases aquosas (ATPS), composto por polietilenoglicol (PEG) e poliacrilato de sódio (NaPA). As duas fases no ATPS NaPA/PEG foram formadas através da mistura dos polímeros com um sal (NaCl) e caldo fermentado de P. fellutanum ou P. restrictum. Para os sistemas formados com o caldo fermentado de P. restrictum foram estudados o efeito da massa molar de PEG (2000, 4000 e 6000 g.mol-1), concentração de PEG (4, 6, 8 e 10% p/p), concentração de NaPA (4, 6, 8, 10, 15 e 20% p/p) e concentração do caldo fermentado (25, 35 e 45% p/p) na partição da enzima a 25 °C. Os valores do coeficiente de partição (K) obtidos variavam de 0,06 a 37,73, mostrando a versatilidade do método para a purificação da biomolécula sob investigação. Na maioria dos sistemas analisados conseguiu-se a partição da biomolécula de interesse para a fase oposta àquela das proteínas totais, proporcionando assim efetiva purificação da enzima. O maior K (partição preferencial na fase rica PEG) foi obtido usando-se: concentração de NaPA igual a 20% p/p, concentração de PEG 2000gmol-1 igual a 4% p/p e concentração de caldo fermentado igual a 45% p/p. Para grande número dos sistemas analisados foram obtidos elevados valores referentes ao balanço de massa (BM) indicando a estabilidade da enzima em relação aos componentes do sistema. Diversos sistemas analisados apresentaram elevados níveis de rendimentos (η) – alguns acima de 90%. Para os sistemas formados com o caldo fermentado de P. fellutanum foram analisados o efeito da massa molar de PEG (2000, 4000 e 6000 g.mol-1), a concentração de PEG (3, 6, 8 e 10 % p/p) e a concentração de NaPA (6, 8, e 10 % p/p) sobre o coeficiente de partição (K) a 25°C. Também foi analisada a influência da concentração de Na2SO4 (5, 10 e 15% p/p) na reextração da enzima. Os valores do coeficiente de partição K obtidos variaram de 1,21 até 77,51. A partição na fase superior foi maior em sistemas com maior concentração de NaPA, maior massa molar de PEG e menor concentração de PEG. Usando a estratégia de reextração foi possível direcionar a partição da protease para a fase oposta às demais proteínas, proporcionando assim uma etapa de prépurificação da biomolécula. Os resultados obtidos através dos APTS NaPA/PEG e posterior reextração com Na2SO4 demonstraram as potencialidades do método no processo de prépurificação de proteases a partir dos caldos fermentados de P. restrictum e P. fellutanum. ____________________________________________________________________________________ ABSTRACT
The development of metologias allowing purification of biomolecules of industrial interest is target of study because of its commercial importance. The partition of proteases produced by fungi of the Brazilian Cerrado, Penicillium fellutanum and Penicillium restrictum, in aqueous two-phase system (ATPS) composed of polyethylene glycol (PEG) and sodium polyacrylate (NaPA) was evaluated. The two phases in ATPS NaPA/PEG were formed by mixing the polymers with a salt (NaCl) and fermented broth of P. fellutanum or P. restrictum. For those systems formed with fermented broth of P. restrictum were studied the effect of molecular size of PEG (2000, 4000 and 6000 g.mol-1), PEG concentration (4, 6, 8 and 10% w/w), concentration NaPA (4, 6, 8, 10, 15 and 20% w/w) and fermented broth concentration (25, 35 and 45% w/w) in partitioning of enzyme at 25°C. The values of partition coefficient (K) obtained varied from 0.064 to 37.73, showing the versatility of the method for the purification of the biomolecule under investigation. In most systems examined it was achieved the partition of biomolecule in the opposite phase to that of total proteins and thus provide effective enzyme purification. The highest K (preferential partitioning in PEG-rich phase) was obtained using: 20% w/w of NaPA concentration, 4% w/w of PEG 2000 g.mol-1 and 45% w/w of broth concentration. For large number of systems analyzed, high values of BM were obtained indicating the stability of the enzyme in relation to system components. Several systems analyzed showed high levels of yield (η) - some over 90%. For those systems formed with the fermented broth of P. fellutanum were analysed the effect of molecular size of PEG (2000, 4000 and 6000 g.mol-1), PEG concentration (3, 6, 8 and 10% w/w) and NaPA concentration (6, 8, and 10% w/w) over the partition coefficient (K) at 25°C. It was also analyzed the influence of Na2SO4 concentration (5, 10 and 15% w/w) in the re-extraction of the enzyme. The values of partition coefficient K obtained ranged from 1.21 to 77.51. The partition in the upper layer was greater in systems with higher NaPA concentration, higher PEG molecular weight and lower PEG concentration. By using the re-extraction strategy it was possible to partition the target protease to the opposite phase to the other proteins, thereby providing a pre-purification step of the biomolecule. The results obtained by ATPS NaPA/PEG/NaCl and subsequent re-extraction with Na2SO4 demonstrated the potential of this method in the pre-purification of proteases from the fermentation broth of P. restrictum and P. fellutanum.

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Mazzeo, Aaron D. (Aaron David) 1979. "Centrifugal casting and fast curing of polydimethylsiloxane (PDMS) for the manufacture of micro and nano featured components." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54660.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 237-248).
The thermosetting resin polydimethylsiloxane (PDMS) is commonly used to prototype micro and nano featured components. In the field of microfluidics, PDMS-based devices have been used for cell sorting, cell culturing, microbioreactors, DNA sequencing, and immunoassays. In energy-related applications, PDMS has been used in fuel cell assemblies and as a material for transferring carbon nanotubes in the construction of solar cells. In addition, PDMS is the fundamental material of soft lithography and microcontact printing. Given the widespread use of PDMS in micro/nano technology, biology, and chemistry, the motivation of this thesis is to outline a viable manufacturing process for thermosetting resins such as PDMS that could be scaled-up for the large-scale production of micro/nano featured components. With respect to rate of PDMS device production, the two time-limiting steps in the typical prototyping process are degassing (bubble removal) and curing. To improve the degassing step, a novel centrifugal casting method is introduced, which permits simultaneous patterning of multiple surfaces and precise thickness control of a PDMS part. To improve the curing step, a custom-designed thermal management system heats and cools the PDMS. In centrifugal casting, the spinning time required to produce a bubble-free part is dependent on a distribution of critical bubble sizes, the centrifuge's spin speed profile, geometry, and fluid properties. A physical model predicting the spin time for bubble removal is verified by high speed video imaging and the production of bubble-free parts.
(cont.) In addition to producing bubble-free parts, the PDMS centrifugal casting technique is utilized to produce micro and nano featured components.
by Aaron D. Mazzeo.
Ph.D.

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Mengestab, Tsegay. "Fate and Transport of Nano-TiO2 in Saturated Porous Media: Effect of pH, Ionic Strength and Flow Rate." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-252835.

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Titanium dioxide nanoparticles are widely used in a variety of products, such as pigments, paints, paper, plastics, cosmetics, nano-fibers, food coloring and photovoltaic cells, and the industry is growing at anexponential rate. It is believed that by 2025, 2.5 million tons of nano-TiO2 will be manufactured annually. Thus far, there has been very little research in the environmental impact of nano-TiO2. There is a need to understand the fate and transport of nanoTiO2 to mitigate their effect on human health, the ecosystems and the environment in general. The aim of this study was to investigate the impact of pH, flow rate and ionic strength on the deposition of nano-TiO2 in a saturated porous media (sand). Nano-TiO2 formed aggregates in solutions that had a pH near the point of zero charge for TiO2, which is at approximately pH 6.2 for TiO2. The formed aggregates showed very little mobility due to site blocking in the pores of the sandy medium, whereas at pH 7.5, the solutions’ concentration was more stable than at pH 6.3 and more mobile up to 10 mM. Above 10 mM, a decrease in mobility, due to reduction in repulsive energy interaction between the medium and the nanoparticles could be observed. Flow rate had also a marked effect on the deposition, i.e., the slower the flow rate, the higher on deposition, because of an increase in attachment efficiency. To verify the experimental results, a finite element solution of the reactive transport equation in one dimension was used to compare the fit between observed and simulated results. The model was run in inverse mode, to determine unknown parameter values such as dispersivity and detachment rate. In general, it was possible to obtain a good fit to theexperimental BTCs.
Nanopartiklar av titaniumdioxid används allmänt i en mängd olika produkter, såsom pigment, färger,papper, plast, kosmetika, nanofibrer, matfärgläggning, och solceller. Branschen växer explosionsartat.Man tror att år 2025 kommer 2,5 miljoner ton nano-TiO2 tillverkas årligen. Hittills har väldigt lite forskning gjorts på området nano-TiO2. Det finns ett behov av att förstå transportprocesser och vad som händer med nanoTiO2 i miljön för att bla kunna mildra effekter av dessa partiklar på människors hälsa, ekologi och miljö. Syftet med denna studie var att undersöka effekten av pH, flöde och jonstyrka (IS) på transporten av nano - TiO2 i vattenmättade porösa medier (sand). Nano - TiO2 bildade aggregat i lösningar som hade ett pH nära pH(PZC), pH(PZC) är pH-värdet vid vilket laddningen är noll, ungefär pH 6,2 för TiO2. Vid pH 6,3 visade nano partiklarna mycket liten rörlighet på grund av fysisk igentäppning i porerna av sandmediet, medan vid pH 7,5 var lösningens koncentration mer stabil och partiklarna mer mobila upp till en jonstyrka på 10 mM. Över 10 mM, observerades en minskning i rörlighet, på grund av minskad repellerande energi mellan mediet och nano partiklarna.Flödeshastighet hade också en markant inverkan på retentionen av partiklar i kolonnen, ju långsammare flöde, desto större retention, på grund av mer gynnsamma förhållande för fastläggning av partiklar till mediet. För att verifiera de experimentella resultaten och jämföra observerade och simulerade resultat användes en lösning med finita-elementmetoden av den reaktiva transportekvationen i en dimension. Inversmodellering gjordes för att ta reda på okända parametervärden såsom dispersivitet och fastläggning. Det var i allmänhet möjligt att uppnå god överensstämmelse mellan observerade ochexperimentella genombrottskurvor.

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Berthe, Marie-Laurence. "Les mélanomes malins naso-sinusiens : étude anatomo-clinique et immunohistochimique de 14 cas et revue de la littérature." Montpellier 1, 1997. http://www.theses.fr/1997MON11174.

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Fitzner, Arnas Gerald. "Effects of alloying elements on twinning in alpha-titanium alloys." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/effects-of-alloying-elements-on-twinning-in-alphatitanium-alloys(5d94e41b-face-40a9-b2d3-28223a2f28ad).html.

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It has been found that commercially pure (CP) Titanium (Ti) undergoes substantial amount of deformation twinning during plastic forming in a wide range of temperatures and strain rates giving CP-Ti good ductility and allowing up to 90% thickness reduction by cold rolling. Aluminium (Al) rich ! Ti-alloys lack this superior ductility but exhibit therefore up to five times higher yield strength, which was connected experimentally to reduced activity of deformation twinning with addition of Al to Ti. Ultimately this is also valid in the ! phase of two-phase alloys such as Ti6Al4V and thought to be key to the reduced ductility in Al rich alloys. It is to date unclear if ordering of Al in the Ti matrix, a change in the stacking fault energy (SFE) with alloying or a transition of the cellular dislocation structures in CP-Ti to planar slip patterns at high Al contents reduces twin activity. The focus of this dissertation project is therefore the transition of microstructural details and the deformation structures in the ! phase with increasing Al concentration. For simplified investigations binary Ti-Al alloys containing 3.5, 7, 10 and 13at.% Al have been created with comparable grain morphology and texture within this study. For a better understanding of the role of Al also binary Ti-Sn (Tin) alloys (1 & 3.4at.% Sn) and Ti-Zr (Zirconium) alloys (3.6 & 10at.%) as well as an Oxygen (O) rich Ti-10at.%Al and the industrial compositions of Ti6Al4V were produced on the same route and investigated by the same methods. This alloy range allows evaluation of the effects of the c/a ratio, ordering phenomena and the SFE on the twin activity. The knowledge was finally transferred to industrially forged CP-Ti and Ti5Al2.5Sn. TEM and neutron diffraction confirmed the onset of Ti3Al formation from Al concentrations above 7at.% (4wt%), but no ordering of Zr or Sn atoms was found after solution treatments. The evolution of lattice strain and lattice reorientation due to twinning with increasing compressive strain was captured by in-situ experiments under neutron diffraction at Engin-X, ISIS. Post-mortem EBSD micro and macro texture mappings revealed that the twin fraction in Al reduces above a critical concentration of 7at.% (4wt%), which was enhanced with increasing ordering towards Ti3Al. Sn and Zr addition showed no significant effect on the overall twin fraction, but increased twin numbers with facilitated nucleation and impeded twin growth, which may be related to the SFE. Increasing slip planarity and a transition from prismatic slip towards basal slip with addition of Al was found with means of Digital image correlation (DIC). DIC also revealed intense prismatic slip in grains undergoing !"!! tension twinning and virtually barely any strain accumulation within a twin below 9% plastic strain, rationalised by much increased nanohardness in the twin in comparison to the parent. Nanoindentation also revealed that alloying with Al reduces the crystal anisotropy. Finally it is believed that ordering and the closely related transition of slip patterns lead to the reduction in twin activity, while c/a ratio, crystal anisotropy and SFE seem less important.

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Norman, Erik. "Fast i gamla spår? : En studie av gamla idéers betydelse för den svenska försvars- och säkerhetspolitiken idag." Thesis, Uppsala universitet, Statsvetenskapliga institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-323044.

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Adam, Véronique. "Ecotoxicological impact and risk assessment of engineered TiO2 nanomaterials on water, sediments and soil by building a combined RALCA (Risk Assessment – Life Cycle Assessment) model." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAH020/document.

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L’analyse du cycle de vie et l’évaluation du risque ont été combinées afin d’évaluer les impacts et risques potentiels de NMs de TiO2 dans l’eau, les sols et les sédiments à une échelle site-spécifique. Une approche analytique a permis de caractériser les NMs industriels dans les eaux, sols et sédiments et de déterminer leur comportement dans l’eau. Un modèle bayésien a été réalisé pour évaluer leur devenir dans les eaux et sédiments de la rivière, ainsi que leurs effets et risques associés en mésocosmes. Il a ainsi été montré que le TiO2 est présent en faible concentration dans l’eau de rivière. En mésocosmes, des risques ont été quantifiés sur deux espèces : Dreissena polymorpha et Gammarus roeseli. Il est apparu nécessaire de mieux caractériser la dimension fractale des agrégats de NMs pour comprendre leur sédimentation et de quantifier les effets des nano-TiO2 dans le milieu naturel, en dépassant l’approche par mésocosmes
In this work, life cycle and risk assessments were combined in order to assess the potential impacts and risks of TiO2 NMs in water, soils and sediments at a site-specific scale. Two approaches were used: (1) An analytical approach allowed the analysis of waters, sediments and soils, the characterization of industrial NMs and the determination of their aggregation behavior in water; (2) A Bayesian modeling approach was used to assess their fate in the river water and sediments, as well as their potential effects and risks in mesocosms. It was thus shown that TiO2 occurs at low concentrations in the river water. Quantifying the TiO2 mass which deposits on the sediment requires characterizing more precisely their fractal dimension. Finally, nano-TiO2 were shown to induce risks to two species in mesocosms: it is consequently necessary to assess the potential effects of the nano-TiO2 produced on the study area in mesocosms, simulating realistic conditions

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Busch, Jan, Tobias Meißner, Annegret Potthoff, and Sascha Oswald. "Plating of nano zero-valent iron (nZVI) on activated carbon : a fast delivery method of iron for source remediation?" Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2011/5379/.

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The use of nano zerovalent iron (nZVI) for environmental remediation is a promising new technique for in situ remediation. Due to its high surface area and high reactivity, nZVI is able to dechlorinate organic contaminants and render them harmless. Limited mobility, due to fast aggregation and sedimentation of nZVI, limits the capability for source and plume remediation. Carbo-Iron is a newly developed material consisting of activated carbon particles (d50 = 0,8 µm) that are plated with nZVI particles. These particles combine the mobility of activated carbon and the reactivity of nZVI. This paper presents the rst results of the transport experiments.
Der Einsatz von elementarem Nanoeisen ist eine vielversprechende Technik zur Sanierung von Altlastenschadensfällen. Aufgrund der hohen Oberäche und der hohen Reaktivität kannn ZVI chlororganische Schadstoffe dechlorieren und zu harmlosen Substanzen umwandeln. Der Einsatz von Nanoeisen zur Quellen- und Fahnensanierung wird jedoch durch mangelnde Mobilität im Boden im eingeschränkt. Carbo-Iron ist ein neu entwickeltes Material, das aus Aktivkohlepartikeln (d50 = 0,8 µm) und nZVI besteht. Diese Partikel kombinieren die Mobilit ät von Aktivkohle mit der Reaktivität von nZVI. Dieser Artikel beschreibt erste Ergebnisse von Transportuntersuchungen.

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Goetz, Rodolphe. "Le traitement médico-chirurgical de la polypose naso-sinusienne : critères d'évaluation post-opératoire des résultats." Montpellier 1, 1991. http://www.theses.fr/1991MON11018.

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Rushiti, Arben. "La communauté internationale face à la crise du Kosovo : de l'éclatement de l'ex-Yougoslavie à l'intervention de l'OTAN (1991-1999)." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAH035.

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De l’éclatement de l’ex-Yougoslavie en 1991 à la montée des tensions à la fin de 1997, la crise du Kosovo a été insuffisamment considérée par la communauté internationale, qui était accaparée par la gestion des conflits ouverts en Croatie et en Bosnie. Mais l’éclatement du conflit armé au début de 1998 poussa la communauté internationale à réagir au Kosovo. Or, cette réaction était à la fois tardive et insuffisante pour permettre de parvenir à une solution diplomatique du conflit. L’une des interrogations de ce travail est donc de déterminer si un règlement politique et pacifique du conflit était possible. Si, avant le conflit armé, tout n’a pas été tenté pour prévenir son éclatement, les chances de trouver une solution politique une fois les hostilités déclenchées, étaient illusoires. Aussi, toutes les initiatives entreprises par la communauté internationale au cours de l’année 1998 et le début de 1999 échouèrent.L’absence d’une solution diplomatique conduisit l’OTAN à intervenir militairement contre l’ex-République fédérale de Yougoslavie, entre mars et juin 1999. Les raisons qui ont motivé cette intervention constituent un autre questionnement important de cette thèse. Dans cette crise, l’OTAN semble avoir subi l’évolution de la situation plus qu’elle ne l’a précédée et anticipée. Selon notre hypothèse, l’Alliance atlantique s’est impliquée dans le conflit en espérant que ses menaces lui éviteraient une intervention militaire qu'elle croyait brève lorsque celle-ci devint inévitable. En entendant mettre fin au conflit par une démonstration de force contre Belgrade, l’OTAN se retrouva donc engagée dans une guerre qu'elle devait mener jusqu'au bout, car il en allait de sa propre crédibilité. Si d’autres facteurs ont également joué un rôle important, l’enjeu de crédibilité nous semble donc constituer l'élément déclencheur de l’intervention de l’OTAN, puis son moteur au fur et à mesure qu’elle se prolongeait et s’intensifiait
From the collapse of former Yugoslavia in 1991 to the rising tensions at the end of 1997, the crisis of Kosovo had not been sufficiently considered by the international community, which was preoccupied with the management of open conflicts in Croatia and Bosnia. However, the outbreak of the armed conflict in early 1998 pushed the international community to react in Kosovo. That reaction was both late and insufficient to achieve a diplomatic solution for the conflict. One of the research questions of this work was to determine whether a political and peaceful resolution of the conflict was indeed possible. If, before the armed conflict, everything was not attempted to prevent its outbreak, chances to find a political solution, once the hostilities began, were illusory. Therefore, all of the initiatives undertaken by the international community during 1998, and in early 1999, were to no avail.In absence of any diplomatic solution, NATO intervened militarily against the former Federal Republic of Yugoslavia, from March to June 1999. The reasons behind this intervention constitute another important question of this thesis. In this crisis, NATO seems to have undergone the evolution of the situation rather than precede and anticipate it. According to our hypothesis, the Atlantic Alliance was involved in the conflict hoping that, by its threats, would avoid the need for a military intervention; and when the intervention became inevitable, NATO believed it to be short. Waiting to put an end to the conflict through military force demonstration against Belgrade, NATO found itself engaged in a war that had to be carried to the end, because its own credibility was at stake. While other factors have also played an important role, the issue of credibility seems to us to have been the major element that triggered NATO's intervention, and as such became its driving force as the intervention prolongated and intensified progressively

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Oliveira, Mariana Fernandes Mendes de [UNESP]. "Respostas metabólicas e da técnica de nado durante o exercício realizado na velocidade correspondente à máxima fase estável de lactato sanguíneo determinada de forma contínua e intermitente." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/87460.

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Made available in DSpace on 2014-06-11T19:22:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-18Bitstream added on 2014-06-13T18:49:50Z : No. of bitstreams: 1 oliveira_mfm_me_rcla.pdf: 189165 bytes, checksum: a4bab800dd002ebdbcf3ba192de703c9 (MD5)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O principal objetivo deste estudo foi comparar a velocidade, concentração de lactato sanguíneo e os índices técnicos correspondentes à máxima fase estável de lactato sanguíneo obtida de forma contínua e intermitente na natação. Participaram deste estudo, 5 nadadores fundistas e 8 triatletas (23 + 9 anos, 1,76 + 0,1 m e 71,3 + 9,8 kg), com pelo menos 3 anos de experiência nas respectivas modalidades. Os indivíduos realizaram em diferentes dias, os seguintes testes, em uma piscina de 25 m: 1) repetição máxima na distância de 400 m; 2) teste incremental para a determinação do limiar de lactato (LL) e limiar anaeróbio (LAn); 3) 2 a 4 repetições com duração de 30 min em diferentes intensidades, para a determinação da máxima fase estável de lactato sanguíneo contínua (MLSSC), e; 4) 2 a 4 tentativas de 12 x 150 s com intervalo de 30 s (5:1) em diferentes intensidades, para a determinação da máxima fase estável de lactato sanguíneo intermitente (MLSSI). O LAn foi determinado por meio de interpolação linear entre a velocidade e a concentração de lactato, considerando uma concentração fixa de lactato de 3,5 mM. O critério de determinação da MLSSC e da MLSSI foi um aumento menor ou igual a 1 mM de lactato entre o décimo e o trigésimo min de exercício. Os índices técnicos taxa de braçada (TB), comprimento de braçada (CB) e índice de braçada (IB) foram determinados em todos os testes. A TB foi calculada por meio de filmagem utilizando o tempo necessário para se realizar cinco ciclos completos de braçadas. O CB foi calculado dividindo a velocidade pela TB. O IB foi determinado pelo produto da velocidade e o CB. De acordo com os dados do presente estudo, a máxima fase estável de lactato sanguínea é atingida em uma velocidade maior quando esta é determinada de forma intermitente (1,17 + 0,09 m.s-1) do que de forma contínua (1,13 + 0,08 m.s-1)...
The main objective of this study was to compare the speed, blood lactate concentration and technical indexes corresponding to the maximal lactate steady state obtained with continuous and intermittent protocols. Thirteen endurance swimmers and triathletes (23.8 ± 9.5 yr., 1.76 ± 0.1 m and 71.3 ± 9.8 kg) participated of this study. The athletes had at least 3 years of experience in swimming. The individuals performed in different days, the following tests: 1) Maximal performance tests of 400 m; 2) Progressive test until exhaustion to determine the anaerobic threshold (AT); 3) 2 to 4 30-min repetitions in different intensities, to determine continuous maximal lactate steady state (MLSSC), and; 4) 2 to 4 trials of 12 x 150 s with 30 s of rest (5:1) at different intensities, to determine the intermittent maximal lactate steady state (MLSSI). The AT was determined trough linear interpolation between the speed and blood lactate concentration, considering a fixed blood lactate value of 3.5 mM. The criterion for the determination of MLSSC and MLSSI was an increase lower or equal to 1 mM of lactate between tenth and thirty min of exercise. Technical indexes stroke rate (SR), stroke length (SL) and stroke index (SI) were determined in all tests. The TB was calculated trough film using the time to perform five complete stroke cycles. The CB was calculated trough the quotient between the speed and SR. The SI was determined by the product of the speed and SL... (Complete abstract click electronic access below)

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36

Oliveira, Mariana Fernandes Mendes de. "Respostas metabólicas e da técnica de nado durante o exercício realizado na velocidade correspondente à máxima fase estável de lactato sanguíneo determinada de forma contínua e intermitente /." Rio Claro : [s.n.], 2008. http://hdl.handle.net/11449/87460.

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Orientador: Camila Coelho Greco
Banca: Mauro Gonçalves
Banca: Luiz Guilherme Antonacci Guglielmo
Resumo: O principal objetivo deste estudo foi comparar a velocidade, concentração de lactato sanguíneo e os índices técnicos correspondentes à máxima fase estável de lactato sanguíneo obtida de forma contínua e intermitente na natação. Participaram deste estudo, 5 nadadores fundistas e 8 triatletas (23 + 9 anos, 1,76 + 0,1 m e 71,3 + 9,8 kg), com pelo menos 3 anos de experiência nas respectivas modalidades. Os indivíduos realizaram em diferentes dias, os seguintes testes, em uma piscina de 25 m: 1) repetição máxima na distância de 400 m; 2) teste incremental para a determinação do limiar de lactato (LL) e limiar anaeróbio (LAn); 3) 2 a 4 repetições com duração de 30 min em diferentes intensidades, para a determinação da máxima fase estável de lactato sanguíneo contínua (MLSSC), e; 4) 2 a 4 tentativas de 12 x 150 s com intervalo de 30 s (5:1) em diferentes intensidades, para a determinação da máxima fase estável de lactato sanguíneo intermitente (MLSSI). O LAn foi determinado por meio de interpolação linear entre a velocidade e a concentração de lactato, considerando uma concentração fixa de lactato de 3,5 mM. O critério de determinação da MLSSC e da MLSSI foi um aumento menor ou igual a 1 mM de lactato entre o décimo e o trigésimo min de exercício. Os índices técnicos taxa de braçada (TB), comprimento de braçada (CB) e índice de braçada (IB) foram determinados em todos os testes. A TB foi calculada por meio de filmagem utilizando o tempo necessário para se realizar cinco ciclos completos de braçadas. O CB foi calculado dividindo a velocidade pela TB. O IB foi determinado pelo produto da velocidade e o CB. De acordo com os dados do presente estudo, a máxima fase estável de lactato sanguínea é atingida em uma velocidade maior quando esta é determinada de forma intermitente (1,17 + 0,09 m.s-1) do que de forma contínua (1,13 + 0,08 m.s-1)... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The main objective of this study was to compare the speed, blood lactate concentration and technical indexes corresponding to the maximal lactate steady state obtained with continuous and intermittent protocols. Thirteen endurance swimmers and triathletes (23.8 ± 9.5 yr., 1.76 ± 0.1 m and 71.3 ± 9.8 kg) participated of this study. The athletes had at least 3 years of experience in swimming. The individuals performed in different days, the following tests: 1) Maximal performance tests of 400 m; 2) Progressive test until exhaustion to determine the anaerobic threshold (AT); 3) 2 to 4 30-min repetitions in different intensities, to determine continuous maximal lactate steady state (MLSSC), and; 4) 2 to 4 trials of 12 x 150 s with 30 s of rest (5:1) at different intensities, to determine the intermittent maximal lactate steady state (MLSSI). The AT was determined trough linear interpolation between the speed and blood lactate concentration, considering a fixed blood lactate value of 3.5 mM. The criterion for the determination of MLSSC and MLSSI was an increase lower or equal to 1 mM of lactate between tenth and thirty min of exercise. Technical indexes stroke rate (SR), stroke length (SL) and stroke index (SI) were determined in all tests. The TB was calculated trough film using the time to perform five complete stroke cycles. The CB was calculated trough the quotient between the speed and SR. The SI was determined by the product of the speed and SL... (Complete abstract click electronic access below)
Mestre

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Kunadian, Illayathambi. "NUMERICAL INVESTIGATION OF THERMAL TRANSPORT MECHANISMS DURING ULTRA-FAST LASER HEATING OF NANO-FILMS USING 3-D DUAL PHASE LAG (DPL) MODEL." UKnowledge, 2004. http://uknowledge.uky.edu/gradschool_theses/324.

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Ultra-fast laser heating of nano-films is investigated using 3-D Dual Phase Lag heat transport equation with laser heating at different locations on the metal film. The energy absorption rate, which is used to model femtosecond laser heating, is modified to accommodate for three-dimensional laser heating. A numerical solution based on an explicit finite-difference method is employed to solve the DPL equation. The stability criterion for selecting a time step size is obtained using von Neumann eigenmode analysis, and grid function convergence tests are performed. DPL results are compared with classical diffusion and hyperbolic heat conduction models and significant differences among these three approaches are demonstrated. We also develop an implicit finite-difference scheme of Crank-Nicolson type for solving 1-D and 3-D DPL equations. The proposed numerical technique solves one equation unlike other techniques available in the literature, which split the DPL equation into a system of two equations and then apply discretization. Stability analysis is performed using a von Neumann stability analysis. In 3-D, the discretized equation is solved using delta-form Douglas and Gunn time splitting. The performance of the proposed numerical technique is compared with the numerical techniques available in the literature.

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Delshadi, Sarah. "Tests de diagnostic immunologique rapides combinant des nanoparticules magnétiques et des micro-aimants structurés." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAV070.

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Cette thèse présente le développement de tests immunologiques innovants, rapides et sensibles combinant des nanoparticules superparamagnétiques (SPN) fonctionnalisées et des micro-aimants : nos immuno-essais magnétiques exploitent les forts gradients de champ magnétique de ces micro-aimants pour capturer les complexes immunologiques liés aux SPN. L’attraction magnétique est souvent utilisée en biotechnologies car elle peut générér des forces capables de capturer des molécules d’intérêt. Les immuno-essais sur billes utilisent habituellement des aimants centi- et millimétriques pour capturer des micro-particules. Réduire la taille des particules magnétiques est très intéressant pour réduire les cinétiques de réactions, tout en diminuant les phénomènes de sédimentation et d’agrégation. Cette réduction d’échelle des particules permet aussi d’augmenter la surface de réaction et ainsi d’augmenter la sensibilité des tests. Cependant les aimants millimétriques génèrent des gradients faibles qui capturent difficilement les SPN, trop mobiles. Les micro-aimants de l’Institut Néel génèrent des forts gradients locaux et ainsi des forces magnétiques importantes. Ces technologies innovantes sont utilisées dans cette thèse pour développer des immuno-essais rapides tirant profit de la réduction d’échelle des particules et des aimants, par rapport aux technologies commerciales.Dans un premier temps, nous avons développé un test immunologique magnétique (MagIA) colorimétrique, comme approche innovante du test ELISA. Nous avons réalisé une preuve de concept pour la détection d’anticorps dirigé contre l’ovalbumine et comparé les résultats avec ceux de tests ELISA. Le test MagIA optimisé présente une limite de détection et une zone dynamique similaires au test ELISA développé avec les mêmes réactifs biologiques. Les micro-aimants fabriqués selon la méthode de micro-magnetic imprinting sont intégrés à bas coût dans les micro-puits des plaques multi-puits ELISA, et permettent la capture efficace des complexes immunologiques couplés aux SPN. La méthode est générique est permet de réaliser des tests ELISA en 30 minutes avec le même équipement.Nous avons ensuite développé un test magnétique immunologique avec une détection fluorescente locale tirant profit des propriétés de capture locale des SPN sur les micro-aimants. Ce test permet la quantification de la molécule d’intérêt en à peine 15 minutes sans étape de lavage. Une preuve de concept réalisée sur la détection de l’anticorps anti-ovalbumine a été réalisée, avec des anticorps de détection fluorescents et des micro-aimants fabriqués selon la méthode de thermo-magnetic patterning. La mesure différentielle entre le signal fluorescent provenant des complexes immunologiques couplés aux SPN localisées sur les micro-aimants, et le signal non spécifique (à l’extérieur des micro-aimants) permet la quantification d’une molécule. Ce test MLFIA (magnetically localized FIA) possède des performances jusqu’à 100 fois meilleures que les tests ELISA standard, pour la détection d’anticorps anti-ovalbumine en PBS. Le test MLFIA a ensuite été transféré à la détection de paramètres cliniques tels que la protéine C réactive, l'ostéopontine, et les sérologies de la toxoplasmose (IgG et IgM). La comparaison des résultats avec des méthodes automatisées a montré d’excellentes corrélations. Le test MLFIA présente plusieurs avantages : il est versatile, compatible avec les milieux biologiques, utilise de faibles volumes et requiert peu d’énergie. Ces résultats ouvrent la voie à une nouvelle génération de tests immunologiques sensibles et nous développons désormais un lecteur miniature pour le diagnostic portable
This thesis reports the development of innovative, sensitive and fast immunoassays combining functionalized superparamagnetic nanoparticles (SPN) and micro-magnets. Our magnetic immunoassays exploit high gradients generated by micro-magnets to capture immune-complexes captured on SPN. Magnetic attraction is widely used in biotechnology, because it provides long-range forces able to capture molecules of interest. Bead-based immunoassays use common centimetre-scale magnets to attract micro-particles. Those magnets generate low magnetic gradients and struggle to capture superparamagnetic nano-particles, which are too small and mobile to be efficiently trapped. Down-scaling the size of magnetic particles is very interesting since it allows diffusion-based transport to perform faster reactions, while avoiding particle sedimentation and aggregation. Furthermore, it increases the reaction surface, which improves the sensitivity of immunoassays. Thanks to the scaling law effects micro-magnets from Institut Néel generate high local gradients and therefore large magnetic volume forces: we use this innovative technology to develop fast immuno-assays that take advantage of a radical size reduction, compared to commercial technology.We first developed a colorimetric magnetic immunoassay (MagIA) as a new approach to standard ELISA. A proof-of-concept based on colorimetric quantification of anti-ovalbumin antibody in buffer was performed and compared with conventional ELISAs. After optimization, MagIA exhibits a limit of detection and dynamic range similar to ELISAs developed using the same biochemical tools. Micromagnets made by the micro-magnetic imprinting method can be fully integrated in multi-well plates at low cost, allowing the efficient capture of immuno-complexes carried by SPNs. The method is generic and performs magnetic ELISA in 30 min.We then developed a magnetically localized fluorescent immunoassay (MLFIA) exploiting the local capture of SPN on micro-magnets. The differential measurement of fluorescence localized on and besides micro-magnet arrays allows the detection and quantification of a molecule in only 15 minutes without fluid handling. We present a proof of concept based on the detection of monoclonal antibody anti-ovalbumin. Functionalized nanoparticles are incubated with fluorescent detection antibody and the sample containing the molecule to be detected. After a single incubation step, the nanoparticles are captured on micro-magnets made by thermo-magnetic patterning. Fluorescence is then read under a microscope. Differential measurement between the signal from the immunological complex localised on the micro-magnets and the non-specific signal localised besides micro-magnets allows the quantification of mAb anti-OVA. The performance of MLFIA was compared with conventional ELISA and exhibits a limit of detection up to 100 times better for anti-OVA mAb in PBS. For further validation, MLFIA was used to measure clinical parameters: we developed a sandwich assay to detect C-reactive protein, and a serology for Toxoplasma gondii immunoglobulin G and M or osteopontin in human samples. Comparisons with data obtained with routine clinical automatized methods show excellent correlation. Our MLFIA technology presents several key advantages: it is compatible with biological media (serum, plasma), uses small volumes and requires little energy. It also is versatile and thus can be used to detect any antigen or antibody in complex media. We are currently developing a portable prototype for point-of-care diagnostics. The results will open the way to a new generation of sensitive immunological lab-on-chip

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Zhang, Wen. "Characterizing, imaging, and quantifying the environmental behavior and biological interactions of metal-based nanoparticles." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/44822.

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Due to the rapid expansion of nanotechnology and the increasing applications of nanomaterials under production and development, it is essential evaluate the potential impacts on human health, ecosystems and the environment. This study is specifically focused on the interactions between metal-based nanoparticles (NPs) and target cells, aiming at exploration of the fundamental knowledge essentially useful for understanding nanotoxicity and its connections with particle properties. The whole structure of this study can be divided into three levels: the first level is to quantitatively understand physicochemical properties of NPs of interest and their dynamic changes under varying environmental conditions. The second level is to evaluate the biological interactions of representative NPs with a specific focus on the size-dependent adsorption processes, interfacial forces, cellular disruption, and membrane damages. The third level is to develop effective, accurate, and valid tools based on atomic force microscopy (AFM) to characterize NPs in terms of the nanoscale hydrophobicity and the nanoscale electric properties, which are most relevant and important properties in the bio-nano interactions. Overall, this study systematically investigated the kinetic environmental behaviors, biological interactions, and unique nano-properties of metal-based NPs, which should be of interest to people in application and implication of nanotechnology.

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Teixeira, da Silva Emerson Rodrigo. "Structure and dynamics of DNA confined in-between non-cationic lipid membranes." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14342/document.

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Une étude expérimentale sur la structure et la dynamique d'un complexe hydraté de fragments d'ADN (150 pb) et des phases lamellaires de lipides non-cationiques est présentée. Par la variation de d'hydratation, il est possible de contrôler le confinement imposé par cette matrice hôte sur les nucléotides insérés dans les couches aqueuses. L’organisation supramoléculaire du complexe est suivie par diffraction des rayons-X et des techniques de microscopie optique et électronique. Un riche polymorphisme de mésophases est observé en fonction du confinement. Dans le régime plus hydraté, les fragments se distribuent selon une orientation nématique. Dans la mesure où la quantité de l'eau diminue, le confinement des bicouches sur les nucléotides monte et des corrélations trans-membranaires donnent origine à des phases hautement organisées, avec de symétries rectangulaires et hexagonales (2D) d'ADN dans la phase lipidique. L'incorporation totale des nucléotides par la phase lamellaire est observée uniquement lorsque des grandes quantités d'ADN y sont présentes. Ce fait souligne une importance majeur des interactions de volume exclu. Une analyse du paramètre de Caillé montre que l'insertion des fragments diminue les fluctuations des membranes. À partir des ces observations, il est suggéré que la modification des interactions stériques entre des lamelles, associée à des effets interfaciaux ADN-membranes, est un mécanisme important dans le comportement de phases. Les propriétés dynamiques sont étudiés avec la technique de retour de fluorescence après photo-blanchiment (FRAP). Un modèle développé récemment pour l'analyse de diffusion anisotrope est testé avec succès, démontrant une corrélation proche entre structure et dynamique
An experimental study on the structural and dynamical properties of a hydrated DNA-non-cationic complex is presented. By varying the water amount, it is possible to control the confinement imposed by this host matrix over the organization of the nucleotides inserted within the water layers. The supramolecular assembly is investigated by X-rays diffraction and techniques involving both optical and electron microscopy. A rich polymorphism of mesophases is observed in function of confinement. In the more hydrated regime, the fragments are distributed according to nematic orientation in-between lamellae. As the water amount decreases, the confinement of bilayers over the particles increases and transmembrane correlations appear, giving raise to highly-ordered phases, with 2D-rectangular and -hexagonal symmetries of DNA embodied in the lamellar phase. The full incorporation of nucleotides by the lamellar phase is observed only in the presence of large amounts of DNA. This finding points to major importance of excluded volume interactions. An analysis of the Caillé parameter shows that the insertion of DNA reduces the fluctuations of membranes. From these observations, it is suggested that changes in the interactions between bilayers, together with the appearance of interfacial effects between DNA and membranes, are a mechanism relevant for the phase behavior of these systems. The dynamical properties of nucleotides are investigated through the fluorescence recovery after photobleach (FRAP). A model recently developed for analyses of anisotropic diffusion is sucessfully tested, demonstrating a close relationship between structure and dynamics
Um estudo experimental sobre aspectos estruturais e dinâmicos de um complexo hidratado de fragmentos de DNA (150 pb) e fases lamelares de lipídios não-catiônicos é apresentado. Variando-se a hidratação, é possível controlar o confinamento imposto por essa matriz hospedeira sobre os nucleotídeos inseridos na camada aquosa. O arranjo supramolecular do complexo é investigado por difração de raios X e técnicas de microscopia óptica e eletrônica. Um rico polimorfismo de mesofases é observado em função do confinamento. No regime mais hidratado, os fragmentos se distribuem segundo uma orientação nemática entre as membranas. À medida que a quantidade de água diminui, o confinamento das bicamadas sobre os nucleotídeos aumenta e correlações transmembranares aparecem, dando origem a fases altamente organizadas, com simetrias retangulares e hexagonais 2D de DNA entre as lamelas. A incorporação completa de nucleotídeos é observada apenas quando grandes quantidades de DNA estão presentes. Esse fato aponta para importância maior de interações de volume excluído. Uma análise do parâmetro de Caillé mostra que as flutuações das membranas diminuem com a inserção de DNA. A partir dessas observações, é sugerido que a alteração das interações entre membranas, aliada à aparição de efeitos interfaciais entre DNA e membranas, é um mecanismo relevante no comportamento de fase. As propriedades dinâmicas dos nucleotídeos são investigadas através da técnica de FRAP (fluorescence recovery after photobleaching). Um modelo recentemente desenvolvido para análise de difusão anisotrópica é testado com sucesso, demonstrando estreita correlação entre estrutura e dinâmica

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Reis, Ivan Gustavo Masselli dos [UNESP]. "Análise de parâmetros de força e padrão de nado de ratos controles e obesos, a partir de um sistema de aquisição de sinais em natação atada: Influência da intensidade do exercício e da densidade corporal." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/87482.

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No modelo de natação para ratos, a associação das intensidades de exercício determinadas por meio da lactacidemia com as suas respectivas sobrecargas são passíveis de crítica, uma vez que a quantificação dos pesos atados ao animal pode não representar efetivamente o esforço real do animal para sua manutenção na superfície da água, devido a esta metodologia sofrer influência da densidade corporal e dos padrões de nado apresentados pelos animais. O principal objetivo desse estudo foi desenvolver um modelo de natação atada para roedores o qual permitiu a determinação direta e em tempo real da força de nado realizada pelo animal e verificar a possível existência de diferentes padrões de nado. Além disso, foi feita a discriminação da densidade corporal em animais controles e induzidos à obesidade, com intuito de destacar consistentemente a influência da flutuabilidade na natação. Foram utilizados 24 rattus norvegicus albinus, machos, com 150 dias de idade, divididos em animais controles e induzidos à obesidade por meio da redução de ninhada somada a uma dieta hiperlipídica. Os animais tiveram a densidade corporal determinada por meio de um aparato de pesagem hidrostática utilizando um sistema de aquisição de dados. Posteriormente todos os ratos foram avaliados no teste de máxima fase estável de lactato adaptado para natação atada. Por meio do modelo experimental de indução a obesidade, foi possível induzir aumento significativo do peso e volume corporal, alem da redução da densidade corporal dos animais no grupo obeso. As avaliações de animais controles e obesos revelaram a influência significativa da densidade corporal na determinação das intensidades de exercício, principalmente quando as cargas foram expressas em valores absolutos. Estudos que fazem uso do modelo de natação para ratos, principalmente de caráter longitudinal...
In the swimming model for rats, the association between the blood lactate concentration with the exercise intensity could be criticized once the workload quantification could not represent effectively the effort performed by the rat to keep himself on the surface, due to it be affected by the body density and the swimming patterns present by the animals. Thus, the mainly objective of this study was develop a apparatus for tethered swimming for rats, that allows the monitoring of swimming force during all exercise time and to verify the existence of different sorts of swimming patterns. 24 male rattus novergicus albinus, with 150 days of age were used, divided in control and obese induced animals by a nest reduction and hyper-lipid diet. All animals had their body density determined by hydrostatic weighing with an acquiring data device. Later the animals were evaluated in maximal lactate steady state test adapted to the tethered swimming. Was possible to induce significant weight and body volume increase in the obese group beside the reduction of the body density. The assessment of control and obese animals reveled significant body density influence in the workload determination, mainly when the workload was expressed in absolute values. Tethered swimming model allowed the investigation of statistic parameters of the data signal, which showed that the signal amplitude varied in function of the intensity, however the dispersion did not. Also the visual analyses of the force kinetic allowed the identification of 4 swimming patterns and the speculation about the reason and consequences of it incidence. Therefore animals that present such swimming patterns which can influence the assessment should be removed from the sample. Studies that make use of the swimming model for rats, mainly those of longitudinal duration or that make use of interventions that may change the animal’s body composition...(Complete abstract click electronic access below)

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Juvé, Vincent. "Spectroscopie linéaire et ultra-rapide de nanoparticules métalliques : de l’ensemble au nano-objet individuel." Thesis, Lyon 1, 2011. http://www.theses.fr/2011LYO10163/document.

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En passant de l’état massif à la nanoparticule les matériaux métalliques voient certaines de leurs caractéristiques modifiées de manière notable comme par exemple les propriétés optiques avec l’apparition d’une résonance dans le spectre optique, la Résonance Plasmon de Surface Localisée (RPSL) responsable du changement de couleur des nanoparticules métalliques. Les propriétés vibrationnelles et thermiques de nanoparticules métalliques ont été étudiées à l’aide d’une technique de Spectroscopie Femtoseconde. Nous avons montré qu’il était possible d’exciter et de détecter optiquement des fréquences de vibrations mécaniques dans le domaine térahertz pour des nanoparticules de platine composées de moins de cent atomes. D’autre part l’augmentation des effets dus aux interfaces a été mis en évidence sur les propriétés thermiques de nanoparticules d’or et d’argent. La résistance thermique à l’interface, résistance de Kapitza, voit son rôle augmenter lors du transfert thermique à l’échelle nanométrique. Une corrélation entre les valeurs mesurées et les impédances acoustiques des matériaux composants les interfaces a été mise en évidence. Nous avons aussi montré qu’elle augmente quand la température diminue de 300K à 70K. Les propriétés optiques de nanoparticules non sphériques ont été étudiées à l’aide de la Spectroscopie à Modulation Spatiale. Cette technique a permis de repérer puis de caractériser des nano-bâtonnets d’or individuels. Nous avons montré que la largeur spectrale de la RPSL est fortement dépendante de la géométrie des nanoparticules (diamètre et longueur). Cette double dépendance n’est pas prédite par les modèles classiques ou quantique existants
The size reduction of metals, from bulk to nanoparticles, induces significant modifications of their properties. For instance, the optical properties evolve and a new resonance, the localized surface plasmon resonance, appears in the optical spectrum and is responsible for the change of colors of metallic nanoparticles. This work is focused on studies of metals’ properties at the nanometric scale. In the first part, the vibrational and thermal properties are studied with a femtosecond spectroscopy technique. It is shown that it is possible to excite and detect optically vibrational frequencies in the terahertz domain by studying platinum nanoparticles formed by less than 100 atoms. The study of the thermal properties of the metallic nanoparticles (gold and silver) has shown that the boundary effect increases. This thermal boundary resistance, known as the Kapitza resistance, plays a dominant role in the heat transfer at the nanometric scale. A correlation between the experimental values of the thermal boundary resistance and the acoustic impedances of the boundary’s materials has been found. We have also shown that the Kapitza resistance is a decreasing function of the temperature in the 70-300K range. In the second part, the effect of the size reduction on the optical properties of non-spherical nanoparticles is observed. The Spatial Modulation Spectroscopy technique is used in order to locate and study individual gold nanorods. It is shown that the two geometrical parameters (the length and the diameter) of the nanorods influence the spectral linewidth of the localized surface plasmon resonance. This effect is not predicted by existing classical or quantum models

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Koneti, Siddardha. "In situ and 3D environmental transmission electron microscopy of Pd-Al2O3 nano catalysts : Fast tomography with applications to other catalytic systems in operando conditions and to electron beam sensitive nanomaterials." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI123/document.

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Au début du XXIème siècle, la Microscopie Electronique à Transmission en mode Environnemental (ETEM) est devenue l’une des techniques les plus fiables de caractérisation de nanomatériaux dans des conditions simulant leur vie réelle. L’ETEM est maintenant en mesure de suivre l’évolution dynamique des nanomatériaux dans des conditions variables comme l’exposition à des températures élevées, l’observation en milieux liquide ou gazeux à diverses pressions. Parmi différents domaines de recherche et développement concernés, la catalyse peut bénéficier de manière significative des avancées permises par la microscopie électronique environnementale. Cette thèse, dédiée au développement de l’ETEM au laboratoire MATEIS, a commencé avec l’étude du système catalytique Pd-alumine. Les nanoparticules de Pd déposées sur alpha -Al2O3 et delta-Al2O3 sont très utilisées en physicochimie avec un impact environnemental important : en particulier dans le domaine de l’hydrogénation sélective, pour la synthèse de polymères ou l’hydrogénation de CO2 pour la production de méthane. Nous avons tout d’abord effectué des analyses 2D aux différentes étapes du processus de synthèse du catalyseur : imprégnation du précurseur, séchage et chauffage pour la calcination dans l’air à la pression atmosphérique. La motivation de cette approche a été de comparer des analyses post mortem avec des traitements en ETEM où l’évolution des nanoparticules peut être mesurée in situ et pas seulement « avant » et « après ». De manière générale, les études faites en ETEM en 2D donnent un aperçu limité sur la morphologie des objets et la distribution spatiale des nanoparticules supportées. Nous avons développé une nouvelle approche d’acquisition rapide pour collecter dans des temps très courts des séries d’images sous différents angles de vue pour la tomographie électronique, la rapidité de cette acquisition étant un prérequis pour appréhender correctement la morphologie d’un nano-système au cours de son évolution dynamique in situ. La technique a ensuite été utilisée pour l’étude de plusieurs systèmes où une acquisition tridimensionnelle rapide est indispensable, notamment sur un sujet concernant un enjeu sociétal important, la dépollution des moteurs diesel : l’oxydation de la suie a été étudiée in situ sur des supports à base de zircone entre 400 et 600°C et une pression de 2 mbar d’oxygène à différents degrés de combustion, ce qui a permis d’extraire des données cinétiques telle que l’énergie d’activation du processus. La tomographie électronique rapide a été également appliquée à des matériaux sensibles au faisceau électronique, comme des nanocomposites polymères et des objets biologiques, montrant le large spectre d’applications possibles pour cette technique, qui constitue un pas important vers la caractérisation operando 3D de nanomatériaux en temps réel
In the beginning of the XXIst century, Environmental Transmission Electron Microscopy has become one of the reliable characterization techniques of nanomaterials in conditions mimicking their real life. ETEM is now able to follow the dynamic evolution of nanomaterials under various conditions like high temperature, liquid or various gas pressures. Among various fields of research, catalysis can benefit significantly from Environmental Microscopy. This contribution starts with the study of the Palladium-Alumina catalytic system. Pd nanoparticles supported by α-Al2O3 and δ-Al2O3 are of an important physicochemical and environmental interest, particularly in the field of selective hydrogenation in petrochemistry, for the synthesis of polymers or CO2 hydrogenation for methane production. We first performed 2D analyses at different steps of the synthesis process, then the same synthesis steps were performed under in situ conditions. The motivation of this approach was to compare post mortem treatments with ETEM observations. In general, 2D data provide limited insights on, for example, the morphology and position of supported nanoparticles. We have then developed a new fast acquisition approach to collect tomographic tilt series in very short times, enabling to reconstruct nano-systems in 3D during their dynamical evolution. Taking advantage of this approach, we have determined the activation energy for soot combustion on YSZ oxidation catalysts for diesel motors from volumetric data extracted from in situ experiments. Fast electron tomography was also applied to electron beam sensitive materials, like polymer nanocomposites and biological materials, showing the wide spectrum of possible applications for rapid 3D characterization of nanomaterials

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Cao, Jing. "Creation and orientation of nano-crystals by femtosecond laser light for controlling optical non-linear response in silica-based glasses." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS055/document.

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En raison d’un désordre aléatoire à longue distance, un verre présente une symétrie d'inversion telle que la génération de seconde harmonique (GSH) est interdite. Cependant, par irradiation avec un laser femtoseconde (fs) très focalisé, il est possible de précipiter des cristaux optiquement non linéaires, et de rompre la symétrie d'inversion et donc d'induire une GSH. De plus, ceci peut être réalisé localement en trois dimensions. Pour la démonstration, on a appliqué, dans le système vitreux Li₂O-Nb₂O₅-SiO₂ le mode opératoire décrit ci-dessous qui permet la formation de cristaux de LiNbO₃, hautement optiquement non linéaire. La procédure est la suivante : 1) ajustement de la composition chimique du verre pour obtenir un verre suffisamment sensible au laser fs ; 2) contrôle des paramètres du laser (durée d'impulsion, fréquence de répétition des impulsions, vitesse de balayage du faisceau, énergie d'impulsion…) pour obtenir des nanocristaux avec répartition spatiale et taille correcte. En outre, la taille de la zone affectée doit être limitée ; 3) contrôle de l'orientation des nanocristaux. On montre qu'il est possible de satisfaire à cette condition, en contrôlant l'orientation de la polarisation du laser. Ceci a été montré par la méthode de rétrodiffusion d'électrons de diffraction (EBSD). En d'autres termes, ce processus peut être contrôlé directement avec la lumière. En outre, la spectroscopie par rayons X à dispersion d'énergie couplée à la microscopie à transmission électronique à balayage (STEM /EDS) et la microscopie électronique à transmission a révélé une microstructure orientable similaire à celle appelée nanoréseaux formée dans silice. L'originalité est que les nanocristaux optiques non linéaires texturées noyées dans un réseau de "murs" vitreux, sont alignés perpendiculairement à la direction de polarisation du laser. Il en résulte que la biréfringence et la propriété optique non linéaire peuvent être maîtrisées ensemble. Ceci est une percée dans ce travail de thèse. Ces résultats mettent en évidence des modifications spectaculaires de verre par rayonnement laser fs. Avec de nouvelles améliorations dans les techniques de fabrication, l'application de ce travail est de parvenir à réaliser un guide d'ondes biréfringent doubleur ou changeur de fréquences
Due to random disorder, a glass exhibits inversion symmetry such that second harmonic generation (SHG) is forbidden. However, by irradiation with a tightly focused femtosecond (fs) laser, it is possible to induce nonlinear optical crystal precipitation, in order to break the inversion symmetry and thus to induce SHG. Moreover, this can be achieved locally in three dimensions. For demonstration, we applied the procedure described below in the glass system Li₂O-Nb₂O₅-SiO₂ that allows the formation of LiNbO₃ crystal, a highly non linear optical one. The procedure is thus the following: 1) adjustment of the glass chemical composition for obtaining a glass sensitive enough to fs laser. 2) control of the laser parameters (pulse duration, pulse repetition rate, speed of beam scanning, pulse energy…) for obtaining nanocrystals with correct space distribution and size. In addition, the size of the affected zone has to be limited. 3) control of the orientation of the nanocrystals. We show that it is possible to fulfill this condition by controlling the laser polarization orientation. This has been achieved by electron backscatter diffraction method (EBSD). In other words, this process can be controlled with light directly. In addition, energy dispersive X-ray spectroscopy coupled to scanning transmission electron microscopy (STEM/EDS) and transmission electron microscopy revealed an orientable microstructure similar to the one called nanogratings form in silica. The originality here is a textured nonlinear optical nanocrystals embedded in a network of “walls” made of vitreous phase, aligned perpendicular to the laser polarization direction. It results that birefringence and nonlinear optical property can be mastered in the same time. This is a highly valuable aspect of the work. These findings highlight spectacular modifications of glass by fs laser radiation. With further improvements in the fabrication techniques, the application of this work is to achieve SHG waveguide and birefringence-based devices

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Almén, Anton. "Importance of atomic force microscopy settings for measuring the diameter of carbon nanotubes." Thesis, Karlstads universitet, Institutionen för ingenjörsvetenskap och fysik (from 2013), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-74745.

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Carbon nanotubes (CNTs) have gathered a lot of interest because of their extraordinary mechanical, electrical and thermal properties and have potential applications in a wide variety of areas such as material-reinforcement and nano-electronics. The properties of nanotubes are dependent on their diameter and methods for determining this using atomic force microscopy (AFM) in tapping mode assume that the measured height of the tubes represent the real diameter. Based on early, faulty calculations, the forces in tapping mode were assumed to be much lower than in contact mode, however it was later shown that forces in tapping mode can at point of impact rival the forces present in contact mode. This means that there is a potential risk of tube deformation during tapping mode measurements, resulting in incorrectly determined diameters. This work studies CNTs deposited on a silicon-substrate to analyze the effect of three common AFM settings (tapping frequency, free oscillation amplitude and setpoint) to determine their effect on measured CNT diameters and recommendations for choosing settings are given.
Kolnanorör har skapat mycket intresse på grund av sina extraordinära mekaniska, elektriska och termiska egenskaper och har lovande tillämpningar inom en mängd olika områden så som materialförstärkning och nanoelektronik. Kolnanorörens egenskaper påverkas kraftigt av deras diameter och de metoder som använder sig av atomkraftsmikroskopi(AFM) för att mäta diametern hos rören antar att den höjd-data man får fram är ett bra mått på den verkliga diametern hos rören. Baserat på tidiga, felaktiga beräkningar, antog man att kraften i ’tapping mode’ skulle vara mycket lägre än i ’contact mode’ vilket skulle leda till att man inte deformerar ytan man undersöker. Senare forskning visade att kraften mellan spets och prov kan vara lika stor eller rentutav större i tapping mode än i contact mode under det ögonblick då spetsen slår ner i provytan. Det medför att det finns en potentiell risk för att man deformerar kolnanorören när man mäter på dom vilket skulle resultera i att man får felaktiga värden på deras diametrar. Under det här projektet har kolnanorör som placerats på ett kisel-substrat undersökts för att analysera hur tre vanliga inställningar hos AFMet påverkar de erhållna värdena för diametern hos kolnanorören. De tre inställningarna som testats är svängnings-frekvensen, svängnings-amplituden i luft och börvärdet hos svängnings-amplituden.

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Horta, Antonio Carlos Luperni. "Técnicas computacionais inteligentes para a inferência de estado e a otimização de cultivos de Streptococcus pneumoniae." Universidade Federal de São Carlos, 2008. https://repositorio.ufscar.br/handle/ufscar/6950.

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Streptococcus pneumoniae (pneumococo) is a pathogenic bacterium that causes several infections which are aggravated by the increase of serotypes with antibiotics resistance. The development of an effective vaccine against this pathogen is crucial for the prevention of the neumococcal illnesses. Conjugated vaccines, consisting of the capsular polysaccharide joined to a carrier protein, are more efficient in the stimulation of the immunologic memory. The capsular polysaccharide (PS) is present in the capsule that involves the cell. Thus, the conjugated vaccine elaboration involves bacterial cells cultivation for its production. As the organism is cultivated in the oxygen absence, the lactate production is inevitably high, leading to growth inhibition due to lactate accumulation in the medium. To minimize the inhibitory effects of the lactate accumulation and to increase the PS production it is necessary to monitor the process and adequately control the addition of supplementary medium along with the withdrawal of saturated medium. This kind of operation can be performed by carrying out a fed-bath cultivation in a bioreactor connected to a perfusion system. The success on the monitoring, control and optimization of this bioprocess depends on the efficiency of the modeling and simulation resources employed. This research work considers the uses intelligent computational techniques, specifically the technique of heuristical search called simulated annealing (SA) combined with neural networks for the state inference and the optimization of S. pneumoniae cultivations. The proposal was implemented as a computational system that: a) uses the SA for the identification of the values for a set of parameters associated to unstructured models and; b) uses neural networks (individually and grouped as a committee) for the state inference of a culture. The work presents and discusses the results of the system for data sets experimentally obtained and highlights the importance of the proposal for achieving a higher efficiency in the culture control processes.
Streptococcus pneumoniae (pneumococo) é uma bactéria patogênica causadora de várias infecções que são agravadas pelo aumento de cepas com resistência aos antibióticos. O desenvolvimento de uma vacina efetiva contra este patógeno é crucial para a prevenção das doenças pneumocócicas. Vacinas conjugadas, constituídas pelo polissacarídeo capsular ligado a uma proteína carregadora, são mais eficientes no estímulo da memória imunológica. O polissacarídeo capsular (PS) está presente na cápsula que envolve a célula e, desta forma, a elaboração de vacinas conjugadas envolve o cultivo da bactéria para a produção do mesmo. Como o microrganismo é cultivado na ausência de oxigênio, a produção de lactato é inevitavelmente elevada e o seu acúmulo no meio provoca a inibição do crescimento. Para minimizar os efeitos inibitórios da acumulação de lactato e aumentar a produção de PS é necessário monitorar o processo e controlar adequadamente a adição de meio suplementar e a retirada de meio saturado em cultivos operados em batelada alimentada, utilizando biorreatores acoplados a sistema de perfusão. O sucesso no monitoramento, no controle e na otimização deste bioprocesso depende da utilização de recursos de modelagem e de simulação que sejam eficientes. Este trabalho de pesquisa propõe o uso de técnicas computacionais inteligentes, especificamente a técnica de busca heurística chamada de simulated annealing (SA) aliada a redes neurais, para a inferência de estado e a otimização de cultivos de S. pneumoniae. A proposta foi concretizada via desenvolvimento de um sistema computacional que: a) faz uso do SA para a identificação do conjunto de valores de parâmetros associados a modelos não estruturados e; b) usa redes neurais (individualmente e em regime de comitê) para a inferência de estado de um cultivo. O trabalho apresenta e discute os resultados do sistema em conjuntos de dados obtidos experimentalmente e evidencia a importância da proposta para uma maior eficiência no controle de processos de cultivo.

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Battiss, Samir. "Les relations transatlantiques dans le cadre de la politique européenne de sécurité et de défense (PESD) : l’Alliance atlantique face à l’émergence d’un acteur stratégique européen (1989-2009)." Thesis, Paris 2, 2012. http://www.theses.fr/2012PA020056.

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Tentant de sortir du seul modèle connu et qui s’offre aux partenaires européens, à savoir l’OTAN, l’UE se fonde sur un système original et spécifique qui se veut plus efficace devant les défis de sécurité d’aujourd’hui et de demain. En parallèle, l’Alliance atlantique, qui tire pour beaucoup, sa légitimité de l’Histoire du continent européen, essaie de se maintenir en tant qu’acteur privilégié en matière de défense et de sécurité collective. L’objectif de cette thèse est de défendre l’idée de la pertinence de l’Union européenne en tant qu’acteur majeur dans le domaine de la défense et de sécurité tout en mettant en évidence les différences fondamentales entre celle-ci et l’action de l’Alliance atlantique. Ce travail de recherche fournit une analyse doctrinale et conceptuelle, à la fois « éclectique et pluraliste », pour répondre à la question de l’établissement de relations entre plusieurs institutions internationales de sécurité à partir des comportements étatiques en matière de sécurité et de défense collective. Cette analyse ne peut se faire sans se fonder sur les développements politiques et techniques ayant marqué ces vingt-cinq dernières années. Ces faits constituent des éléments tant explicatifs qu’évaluatifs du processus par lequel ces institutions naissent ou se modifient. Ils contribuent également à mettre en lumière les mécanismes d’interdépendance étroite entre l’Alliance atlantique et le processus de la PESD de l’Union européenne, et par ailleurs, de souligner l’originalité de cette dernière. Cette interdépendance existe sur le plan politique et dans ses différents aspects militaires (stratégique, opérationnel et tactique), ainsi que dans le volet technico-industriel ; elle résulte directement tant de la double appartenance historique des États membres à des instruments multilatéraux de sécurité, d’événements politiques majeurs touchant le continent européen, que des efforts entrepris pour faire converger les intérêts nationaux et, donc, le façonnage d’une culture stratégique
The European Union bases its security system on genuine and specific approach which would allow the face the forthcoming challenges. Meanwhile it has attempted to untangle from the unique model of collective security in the Euroatlantic area, that is to say NATO. This study aims to defend the relevancy of the EU as a major international actor in a large scale of security missions. Moreover it highlights the main differences between the EU vis-à-vis the Alliance’s activities. It is based on a theoretical and conceptual analysis which uses both an eclectic and pluralist approach in order to provide answers on how States’ behavior in defense and collective security matters influences the setting up of relations between several international security institutions. This analysis derives from the political and technical developments that influenced the security landscape the last twenty-five years. These facts help to explain and to evaluate the process by which such institutions arise and develop. They finally contribute to highlight the tight and original interdependency of the between the Atlantic Alliance and the European Security and Defense Policy of the European Union. This interdependency is real from political, military (strategic, operational and tactical) and technical-industrial perspectives ; it directly originates from the historical dual belonging to the multinational security frameworks, from major political events on the European continent, as much as a joint effort to focus on common interests and the shaping of a strategic culture

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Montagu, Angélique. "Composants aromatiques nano-encapsulés : une alternative face à la résistance aux antibiotiques : Démonstration des effets biologiques seuls ou nano-encapsulés de l’in vitro à l’in vivo Prevention of Bacterial Infections Using Encapsulated Phytophenolic Actives Aromatic and terpenic compounds loaded in lipidic nanocapsules: activity against multi-drug resisant Acinobacter baumannii assessed in vitro and in a murine model of sepsis Demonstration of the interactions between aromatic compound-loaded lipid nanocapsules and Acinetobacter baumannii bacterial membrane." Thesis, Angers, 2016. http://www.theses.fr/2016ANGE0072.

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Face à la montée en puissance des bactéries multi-résistantes, la découverte de nouvelles stratégies antibactériennes s’impose. Une alternative est l’utilisation de substances actives antibactériennes issues d’huiles essentielles. Ces actifs de nature lipophile, ont été encapsulés via les nanocapsules lipidiques (NCL) pour une utilisation par voie systémique. L’efficacité de ces NCL chargées en actifs a été montrée dans un modèle de sepsis à Acinetobacter baumannii avec un taux de survie de 45% à 55%. Notre étude a montré le pouvoir d’attraction et de pénétration du carvacrol (Car) encapsulé via les fonctions hydroxyles vis-à-vis de la membrane bactérienne. Les effets biologiques de ces actifs ont été caractérisés par une dégradation de l’ARNr et une surexpression des gènes codant pour des heat shock protein. Une surexpression de la catalase due au Car est également observée, en lien avec le stress oxydatif (rôle de détoxification). Nos travaux ont montré que les bactéries pourraient utiliser dans ce processus une stratégie de défense contre le Car en utilisant les ROS endogènes lors d’une réponse au stress environnemental. Ces effets biologiques sont conservés après l’encapsulation des actifs par les NCL. Dans un modèle in vivo de pneumopathie, aucune survie animale n’a été constatée, malgré la post-insertion des NCL, qui est censée augmenter leur furtivité dans le sang. L’infection pulmonaire n’a pas favorisé d’accumulation des NCL dans les poumons. Ce phénomène pourrait s’expliquer par la métabolisation du Cin en acide cinnamique dans le sang, forme oxydée de l’actif qui réduirait drastiquement l’activité antibactérienne des NCL chargées en Car-Cin
Faced with the rise of multidrug-resistant bacteria, the discovery of new antibacterial strategies is imperative. An alternative is the use of antibacterial active substances from essential oils. These lipophilic compounds were encapsulated via lipidic nanocapsules(LNC) allowing a use by systemic way. The efficacy of actives loaded LNC has been showed in a murine model of sepsis against Acinetobacter baumannii with a survival rate of 45% to 55%. Our study showed the power of attraction and penetration of the encapsulated carvacrol (Car) via the hydroxyl functions. The biological effects of these compounds were characterized by a degradation of rRNA, an over expression of genes encoding heat shock proteins. A catalase overexpression was also observed which is related to an oxidative stress (role of detoxification). Our works showed that bacteria could use in this process, a defense strategy against Car using the endogenous reactive oxygen species in response to environmental stress. These biological effects are preserved after encapsulation by LNC. In an in vivo model of pneumonia, no animal survival has been observed, despite the use of pegylated LNC, which is supposed to increase their stealth in the blood. Pulmonary infection did not promote the LNC accumulation in the lungs. This phenomenon could be explained by the metabolization of Cin in cinnamic acid in the blood, the oxidized form ofthe compound which would drastically reduce the antibacterial activity of Car-Cin loaded LNC

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Morais, Jacqueline Moreira de. "Desenvolvimento e avaliação do processo de obtenção de emulsões múltiplas A/O/A em etapa única empregando óleo de canola e tensoativo não iônico derivado do óleo de rícino." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-23072008-152433/.

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As emulsões múltiplas mostram-se como veículos promissores em várias áreas das ciências cosmética e farmacêutica. O estudo do método de obtenção de emulsões múltiplas em etapa única é ferramenta útil para elucidação de seus aspectos físico-químicos e para viabilizar sua aplicação tecnológica. O objetivo da pesquisa foi desenvolver e caracterizar os aspectos físico-químicos do processo de emulsificação em etapa única, das emulsões múltiplas A/O/A obtidas e dos tensoativos empregados. Testes preliminares de estabilidade e avaliação do seu perfil de liberação (cafeína) foram realizados. Nanoemulsões foram inicialmente obtidas pela metodologia proposta, resultado de processo de emulsificação por inversão de fases. Suas características físico-químicas foram determinadas (valores de pH, potencial zeta e granulometria) e a influência de aditivos avaliada. Para o desenvolvimento da emulsão múltipla foram realizadas análises qualitativas e quantitativas das variáveis relevantes à composição (tipo de fase oleosa, de tensoativo hidrofílico, valor de EHL, emprego de diagrama ternário) e ao método de emulsificação (temperatura de aquecimento das fases e de emulsificação, ordem de adição e velocidade de agitação). Os estudos das propriedades físico-químicas dos tensoativos e do filme interfacial formado (cloud point, tensão superficial, CMC, reologia interfacial, reologia de fluxo e isotermas de Langmuir) foram primordiais para compreensão dos fenômenos envolvidos e relevantes ao processo de emulsificação proposto. As emulsões múltiplas foram caracterizadas quanto aos aspectos macro e microscópico, granulometria, valores de pH, potencial zeta, viscosidade relativa, perfil reológico e influência da adição de macromoléculas. A temperatura de manipulação e de emulsificação (78±2grausC) foram parâmetros fundamentais para obtenção destes sistemas em etapa única. Seus aspectos macro e microscópico foram extremamente dependentes da temperatura de emulsificação. Os resultados indicam glóbulos múltiplos consideravelmente menores do que os relatados pela literatura. Foi possível observar, no intervalo de temperatura considerado crítico para o processo, valores de tensão superficial/interfacial mínimos. Os resultados de elasticidade superficial sugerem que o comportamento das moléculas de tensoativos, em associação ou não, foi marcadamente influenciado pela temperatura e que o aumento do número de moléculas do tensoativo hidrofólico na superfície foi desfavorável as interações intramoleculares. A isoterma para os tensoativos em associação e em função da temperatura exibiu marcante inflexão para a faixa de temperatura crítica. Este comportamento indica uma dramática alteração na microestrutura do filme interfacial. O processo de encapsulação foi considerado eficiente. Os resultados obtidos indicam que, no atual estágio de desenvolvimento, não foi possível definir um perfil de liberação para a emulsão múltipla em análise. O método de emulsificação escolhido permitiu a obtenção de sistema múltiplo em etapa única, determinado pelas características físico-químicas dos tensoativos empregados, em especial do tensoativo hidrofílico derivado do óleo de rícino e do processo proposto. A formação de emulsões múltiplas anormais não ocasionais ou momentâneas sugere uma combinação dos processos de inversão de fases transicional, influência do emprego de tensoativos não-iônicos etoxilados, e catastrófica, influência da razão entre o volume da fase dispersa e dispersante. As emulsões múltiplas obtidas apresentaram difícil reprodutibilidade microestrutural; entretanto podem ser consideradas estáveis frente às metodologias de avaliação e análise empregadas.
Multiple emulsions are potential vehicles not only for the cosmetic science, but also for the pharmaceutical science. Study the manufacture process of multiple emulsions by one step is a useful tool for understanding their physical-chemistry aspects and making their technological application practicable as well. The goals of this research were to development and characterize the physical chemistry features of the emulsification process by one step, the W/O/W multiple emulsions produced and the surfactants employed. Preliminary stability tests and evaluation of the release profile (caffeine) were carried out. Initially, nano-emulsions were produced by the proposed methodology, resulting from phase inversion emulsification process. Their physical chemistry aspects (pH and zeta potential values and size distribution) and electrolytes addition influence were evaluated. In order to develop the multiple emulsions, noteworthy qualitative and quantitative variables related to the composition (oil phase and hydrophilic surfactant types, HLB values, phase diagram) and to emulsification process (heating and emulsification temperatures, addition order and agitation speed) were analyzed. Analyses of the physical chemistry aspects of the surfactants in solution and their interfacial film (cloud point, surface tension, CMC, interfacial and flux rheology, and Langmuir isotherms) were essential in order to understand the phenomena related to proposed emulsification process. Multiple emulsion analyses (macroscopic, microscopic, size distribution, pH and zeta potential values, relative viscosity, rheological profile and macromolecule addition influence) were carried out. Production and emulsification temperatures (78±2grausC) were fundamental parameters in order to obtain multiple droplets by one step. Their macro and microscopic aspects were completely conditioned by the emulsification temperature. The sizes of the multiple droplets obtained were significantly smaller than those reported in the literature. For the critical temperature range, the minimum surface tension values were reached. Surface elasticity results suggest that the behavior of the surfactant molecules, in association or not, was fundamentally influenced by the temperature. Increasing surfactant molecule moieties on the surface, the intra molecular interactions were misplaced. The Langmuir isotherm as a function of the temperature demonstrated distinctive behavior for the critical temperature range, where the transition phase into solid state and soon afterwards some collapse could be observed. This phenomenon indicated some dramatic alteration of the surface film microstructure. The encapsulation process was regarded as efficient. The release profile studies demonstrated that the dispersed system in analysis was not ready yet for this research stage. The proposed emulsification process was able to produce multiple droplets by one step; moreover this result presented direct influence of the surfactant physical chemistry features, particularly the hydrophilic one, castor oil derivate, and of the methodology employed. The abnormal, non-occasional and non-transitory, multiple emulsion formation suggest a combination of transitional (ethoxylated non ionic surfactant influence), and catastrophic (dispersed/dispersant ratio influence) phase inversion processes. The obtained multiple emulsions presents microstructure aspects were not easily reproducible; however those were regarded stable for the analysis methodology employed.

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Chen, Li-Hua, and 陳麗華. "Fate of Nano Zinc Oxide in the Aquatic Environment." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/16433419934279812356.

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碩士
國立臺灣大學
環境工程學研究所
97
This study was mainly focused on the behavior of aqueous nano-zinc-oxide under different pH, concentration of cations and humic acid. The amount of the stably dispersed nano-zinc-oxide was determined by measuring the total particle concentration in the supernatant (detected by atomic absorption spectrometry) and zeta potential of the particle surface. The results showed that the nano-zinc-oxide existed mainly in dissolved form, at lower pH(<8),and the amount of zinc particles in the supernatant could not be determined. On the contrary, under higher pH the nano-zinc-oxide particles formed aggregated easily when the pH of the solution equaled approximately to 8, the isoelectric point (IEP). The effects of the concentration of cations on nano-zinc-oxide aggregation and dispersion were investigated by adding 0.1mM KCl or CaCl2 to the nano-zinc-oxide suspensions. The variations of the energy barrier between supernatant nano-zinc-oxide particles were calculated by using Derjaguin Landau Verwey Overbeek (DLVO) theory. The results revealed that the energy barrier between particles in the presence of K+ was higher than that of Ca2+, and the efficiency of nano-zinc-oxide dispersion by adding K+ was higher than that with Ca2+ by 20%. Besides, the nano-zinc-oxide dispersion was also affected by the presence of humic acid ( a naturally occuringe organic matter in the aquatic environment). Under lower humic acid concentrations(0.5 to 50 mg/L), due to that the zeta potential of the nano-zinc-oxide decreased from 30.7 ± 1.13 mV from without humic acid to -3.93 ± 3.32 mV and the static-electric repulsion between particles diminished, there were dramatic particle collision and sedimentation. The stably dispersed nano-zinc-oxide in the supernatant was only 20%. However, with higher humic acid concentration(2.0 to 50 mg/L), the concentration of the stably dispersed nano-zinc-oxide was higher than that with lower humic aicd concentration by 60% due to that the surface of nano-zinc-oxide particles were thoroughly covered with negatively charged humic acid, and the static-electric repulsion increased significantly. Keywords: nano zinc oxidep; humic acid; DLVO theory; Van der Waals forces

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