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A computational study of the effect of cross wind on the flow of fire fighting agentMyers, Alexandra. 06 1900 (has links)
Approved for public release, distribution unlimited / This research will be used to evaluate the feasibility of robotically, or remotecontrolled firefighting nozzles aboard air-capable ships. A numerical model was constructed and analyzed, using the program CFD-ACE, of a fire hose stream being deflected by the influence of a crosswind, tailwind, or headwind. The model is intended to predict the reach of the fire hose stream, indicate the distribution pattern, and estimate the volume of fire fighting agent available at the end of the stream. Preliminary results for a two fluid cross flow model have been obtained. / US Navy (USN) author.
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Steady state and transient measurements within a compressor rotor during steam-induced stall at transonic operational speedsZarro, Sarah E. 09 1900 (has links)
Approved for public release, distribution unlimited / Steam leakage from an aircraft carrier catapult is sometimes ingested into the aircraft engines upon launch which may induce compressor stall. Investigation of this phenomenon is of particular interest to the Navy with its new F35C, the aircraft carrier variant of the joint strike fighter. The single engine configuration of the F-35C makes this aircraft particularly vunerable to steam-induced stall. The present study examined both throttle-induced stall and steam-induced stall in a compressor at 90% and 95% speed through the use of 9 Kulite and 2 hot-film pressure transducers. The use of Fast Fourier Transform waterfall plots of the transient data before and during stall proved invaluable in determining stall precursors as well as the mode of rotor stall. In addition, a new computational fluid dynamic model was designed using CFX-5 software to represent a single blade passage of the compressor rotor, in order to predict compressor performance. The computed results were compared to experimental results gathered at various throttle settings. An accurate model will enable researchers to predict compressor performance for various and multiple gases. / Outstanding Thesis
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Évaluation de la toxicité de nanoémulsions de tributyrine et de docétaxelPerron, Marie-Ève January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
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Aceria tulipae (Kiefer) (Eriophyidae) in relation to the transmission of various strains of wheat streak mosaic virusRosario, Maria Salome Escanilla del. January 1957 (has links)
Call number: LD2668 .T4 1957 R68 / Master of Science
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Desenvolvimento de método analítico para quantificação de antineoplásico em sistemas de liberação controlada de fármacos / Development of analytical method for quantification of antineoplastic in drug delivery systemsPrado, Fernando Kaneko 16 May 2019 (has links)
Nos últimos anos têm crescido cada vez mais o número de pesquisas envolvendo nanotecnologia para obtenção de medicamentos com liberação controlada, pois esses sistemas podem: proteger o fármaco de incompatibilidades tanto biológicas quanto físico-químicas assim como controlar a biodisponibilidade do fármaco. Embora com todas essas vantagens não existem métodos in vitro realmente capazes de prever com precisão a liberação dos fármacos por esses sistemas, por esse motivo, é muito importante o desenvolvimento de métodos de liberação in vitro para determinar a cinética de liberação desses sistemas.O presente trabalho teve como objetivo desenvolver e validar os métodos de eletroforese capilar (CE) e cromatografia líquida de alta eficiência (HPLC) para determinar a eficiência de encapsulação do fármaco imatinibe em nanopartículaspreviamente elaboradas e caracterizadas, assim como estudar sua liberação in vitro por CE. As nanopartículas foramdesenvolvidas pelo método de nanoprecipitaçãoe caracterizadas quanto ao tamanho, potencial zeta, morfologia e eficiência de encapsulação. A eletroforese capilar é uma técnica alternativa muito promissora em relação ao HPLC devido ao seu baixo custo, menor tempo de corrida e menos poluente ao meio ambiente. Os métodos de quantificação por CE e HPLCforam desenvolvidose validadossegundo as diretrizes do ICH, Farmacopeia Americana e ANVISA, permitindo desenvolver um estudo de liberação.As nanoesferas desenvolvidas apresentaram diâmetro médio próximo a 150nm, com índice de polidispersão menor que 0,1 e aproximadamente 90% de eficiência de encapsulação. Ambos métodos se mostraram lineares com coeficientes de determinação superiores a 0,99, os métodos se mostraram precisos (%DPR< 2), exatos(101,0±4,2% e 98,0±2,5% para HPLC e CE, respectivamente)e seletivos.O método de CE permitiu desenvolver um método de estudo de liberação independente das membranas de diálise. / In recent years, there has been a growing number of researches involving nanotechnology to obtain controlled release drugs, these systems can: protect the drug against biological and physico-chemical incompatibilities; controlling the bioavailability of the drug. Although with all these advantages there are no in vitro methods really capable of accurately predicting drugs release by such systems, therefore, the development of in vitro release methods to determine the release kinetics of such systems is very important. The objective of the present work was to develop and validate capillary electrophoresis (CE) and HPLC methods to determine the encapsulation efficiency of the imatinib drug in previously elaborated and characterized nanoparticles, as well as to study its release in vitro by CE method. The nanoparticles were synthesized using the nanoprecipitation method and characterized by size, zeta potential, morphology and encapsulation efficiency. Capillary electrophoresis is a very promising alternative to HPLC because of its low cost, less runtime and less polluting environment. The CE and HPLC methodswere developed and validated according ICH, American Pharmacopoeia and ANVISA guidelines.Developed nanospheres had an average diameter close to 150nm, with polydispersity index less than 0.1 and approximately 90% encapsulation efficiency. Both methods were linear with determination coefficients higher than 0.99, the methods were precise (%RSD < 2), accurate (101.0±4,2% and 98.0±2,5% for HPLC and CE, respectively) and selective. Capillary electrophoresis method allowed to develop a drug release study independent of dialysis membranes.
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Rodina auxinových přenašečů PIN: funkční a evoluční pohled / Rodina auxinových přenašečů PIN: funkční a evoluční pohledSkůpa, Petr January 2011 (has links)
Growth and development of plant body is dependent on correct and effective integration of information about current deployment of its body parts, as well as on perception and transduction of inputs from environment. Multiple developmental processes within plant body are determined by specific and tightly controlled distribution of molecule with unique signaling mission within plant development - auxin. Spatial distribution of auxin is co-determined by plethora of tightly controlled processes, and the polar auxin transport plays unique role among them. PIN proteins are the plant-specific family of secondary transporters driving movement of auxin across membranes. With their frequent asymmetrical localization within cells, specific expression patterns in developing tissues and their reactiveness to external cues they secure unique, dynamic and asymmetric distribution of auxin within the plant body. This dissertation thesis is focused on characterization of the role different PIN proteins play in determining cellular auxin homeostasis and consequent formation of auxin gradients. Controlled overexpression of PIN proteins in tobacco cells showed, that PIN4 and to some extent also PIN6, function as the direct auxin efflux carriers. In the cellular auxin transport they play the role analogous to other...
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Mechanismy regulace aktivity vynašečů auxinu / Mechanismy regulace aktivity vynašečů auxinuKřeček, Pavel January 2011 (has links)
The morphology of plant body is shaped by genetically coded developmental programme together with environmental factors. The influence of environmental factors on the morphology is much more important in plants that in other multicellular organisms. The developmental programme provides a general scheme that is modified by environmental signals. Phytohormone auxin is a regulator of plant morphogenesis and its distribution in the plant body is an important mechanism controling the growth and development of plants and coordinating the developmental programme with environmentally-induced changes. This thesis investigates factors important for transport of auxin from cells, second part is dedicated to bioinformatic analysis of the transporters from the PIN protein family. For investigation of signals involved in regulation of activity of auxin efflux transporters I have selected (based on published information) physiological signals influencing auxin transport. These signals were changed by treatment with chemicals and resulting changes in auxin transport were measured (on the cellular level) with the intention to discover signals that can rapidly (within minutes) change the activity of auxin efflux transporters. The signals, which satisfy these requirements were subjected to further investigation. He detailed...
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Mechanizmus transportu cytokininů přes buněčnou membránu a jejich metabolizmus v buňkách tabákové suspenzní kultury BY-2 / Mechanizmus transportu cytokininů přes buněčnou membránu a jejich metabolizmus v buňkách tabákové suspenzní kultury BY-2Klíma, Petr January 2011 (has links)
MECHANISM OF CYTOKININ TRANSPORT ACROSS PLASMA MEMBRANE AND THEIR METABOLISM IN TOBACCO BY-2 CULTURED CELLS Mgr. Petr Klíma / Abstract of Ph.D. Thesis / Prague 2011 Cytokinins (CKs) are plant hormones that play a major role in a number of developmental processes in plants. Those include promotion of cell division, active growth and differentiation, and maintenance of sink-source relationships, as well as control of environmental stress responses. Native CKs are low-molecular derivatives of adenine which seem to act either as paracrine or as long-distance signals. Due to their numerous physiological effects, plants have to precisely control the occurrence of bioactive CK molecules on the levels of the whole plant, its organs, tissues as well as single cells. To achieve this, a concerted action of metabolism and transport processes is required. Studies of the kinetics of CK translocation across plasma membrane in BY-2 suspension-grown tobacco cells suggested the existence of energy-dependent, partially selective transport routes for CK bases and CK ribosides. HPLC analysis of the metabolites of accumulated CKs pointed at their fast degradation or metabolic conversion into physiologically inactive forms. The prevalent ways of inactivation were the degradation to adenine and phosphorylation or phosphoribosyl...
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Desenvolvimento de anticorpos anti-peptídeos sintéticos derivados da proteína transportadora de fosfato dependente de sódio NaPi2b. / Development of anti-synthetic peptides antibodies derived from sodium-dependent phosphate transporter NaPi2b protein.Megale, Ângela Alice Amadeu 28 November 2014 (has links)
Dois peptídeos, designados Let#1 e Let#2, foram delineados do segundo laço extracelular da proteína NaPi2b. Após conjugação, os peptídeos induziram produção de anticorpos específicos em coelhos e camundongos. Os anticorpos com maiores títulos foram selecionados para ensaios complementares. Estes anticorpos reconheceram os peptídeos conjugados aos carreadores pelos métodos de ELISA e WB, não havendo reação cruzada quando testados com a proteína carreadora livre e com antígeno sintético inespecífico. Após a completa validação, foi possível observar que os anticorpos anti-peptídeos reconhecem NaPi2b nativa, presente na superfície de células OV-CAR, bem como mostraram reconhecimento de um alvo comum em todos os soros analisados, mesmo quando o soro era considerado negativo para COV pelo teste comercial. Este reconhecimento não foi observado quando as amostras foram analisadas pelo soro pré-imune dos animais teste, sugerindo um reconhecimento específico dos anticorpos produzidos. / Two peptides, designated Let#1 and Let#2, were outlined from the second extracellular loop of the NaPi2b protein. After conjugation, the peptides induced the production of specific antibodies in rabbits and mice. Antibodies with higher titers were selected for complementary tests. These antibodies recognized peptides conjugated to the carrier by ELISA and WB, with no cross-reaction when tested with the free carrier protein and nonspecific synthetic antigen. After complete validation, it was observed that the anti-peptide antibodies recognize native NaPi2b protein present on the OV-CAR cell surface and showed recognizing a common target in all sera tested, even when the serum was considered negative for ovarian carcinonoma by commercial test. This recognition was not observed when the samples were analyzed by pre-immune serum of test animals, suggesting specific recognition of antibodies produced.
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Desenvolvimento de carreador lipídico nanoestruturado (CLN) como sistema de co-encapsulação de curcuminóides e timol para aplicação tópica / Development of nanostructured lipid carrier (NCL) as a co-encapsulation system of curcumin and thymol for topical applicationSouza, Patrícia Fernanda de 29 January 2018 (has links)
A pele desempenha um importante papel na homeostasia e é uma via muito utilizada na administração de fármacos. O envelhecimento compromete sua função protetora e contribui para o aparecimento de sintomas como a rugosidade, flacidez, secura, prurido, hiperpigmentação dificuldade de cicatrização e a incidência de melanomas. Os raios UV são a principal causa do envelhecimento devido à geração de espécies reativas de oxigênio (ROS) e peroxidação lipídica. Os danos causados pelos ROS podem ser mitigados pelo uso de antioxidantes tópicos como a curcumina e timol (TML). No entanto, a baixa permeabilidade e estabilidade são fatores limitantes para sua aplicação. Para superar esses desafios, ECUR e TML podem ser encapsulados em nanopartículas, como os carreadores lipídicos nanoestruturado (CLN). Assim, os objetivos desse projeto foi desenvolver um CLN estável com manteiga Illipê, óleo de calêndula e TPGS para co-encapsular ECUR e TML e incorporação em uma formulação tópica. O padrão analítico dos curcuminóides foi isolado de amostra comercial, identificado por LC-MS e RMN e a metodologia analítica para quantificação CUR e TML foi validada. Os CLNs foram produzidos por emulsão quente e sonicação e otimizados utilizando a ferramenta de DoE Box-Behnken. Foram caracterizados em relação às propriedades físicas, citotoxicidade em cálulas HaCaT e atividade antioxidante. O CLN otimizado apresentou tamanho em torno de 130 nm, índice de polidispersão abaixo de 0,200 e potencial zeta negativo. A eficiência de encapsulação foi acima de 97% tanto para TML quanto CUR. CLN com e sem ativos demonstrou baixo índice de recristalização e forma esférica caracterização por DSC e AFM e não foram citotóxicos para células HaCaT, mostrando viabilidade celular superior a 80% na concentração 1,48x1012 partículas/ml, correspondente a 0,8 ?g/ml de TML/CUR co-encapsulados. Além disso, TML/CUR livre e co-encapsulado mostrou alta atividade antioxidante em ensaios in vitro para inibição de xantina oxidade e auto-oxidação do pirrogalol, indicando sua potente capacidade de inibição da enzima superóxido dismutase mesmo quando encapsulados. O emulgel tópico foi desenvolvido e apresentou estabilidade física após a incorporação do CLN no teste de estabilidade acelerada. O perfil reológico do emulgel demonstrou característica plástica e reoplexa e se manteve estável com o tempo e sob as variações de temperatura de analise, indicando alta estabilidade física da formulação. O perfil de liberação de ECUR e TML indicou cinética de liberação correspondente ao modelo de Higuchi sem influência da co-encapsulação na liberação da CUR e com liberação mais lenta do TML encapsulado. Os dados de permeação sugerem que os ativos possam permear na pele. A extensão e a intensidade da permeabilidade dos ativos promovida pelo CLN determinarão a aplicabilidade da formulação que poderá ser interessante para o desenvolvimento de um produto cosmético, dermocosmético, ou mesmo para um medicamento transdérmico. Em conclusão, o CLN desenvolvido apresentou características físicas e biológicas interessantes para a aplicação tópica. / Skin plays an important role in homeostasis and it is an important route for drug delivery. Aging compromises its protective function and contributes to the appearance of symptoms such as roughness, sagging, dryness, pruritus, hyperpigmentation, scarring deficient and the incidence of melanomas. UV rays are the main cause of photo-aging due of ROS generation and lipid peroxidation. ROS damage can be mitigated by using topical antioxidants as curcumin and thymol. However, low permeability and physico-chemical stability are disadvantages for its clinical application. To overcome these challenges, ECUR and TML can be encapsulated in nanoparticles such as nanostructured lipid carriers (NLC). This project aimed to develop a stable NLC composed by Illipê butter, calendula oil and TPGS to co-encapsulate ECUR and TML, followed by the NLC incorporation into a cosmetic formulation. Curcuminoid\'s analytical standard was isolated from commercial sample, identified by LC-MS and NMR, and the analytical methodology for quantification CUR and TML was validated. NLCs were produced by sonication emulsification method and their development was designed by Box-Behnken DoE and characterized in relation to physical properties, HaCaT cell cytotoxicity and antioxidant activity. Optimized NLC with size around 130 nm, polydispersity index (PdI) below 0.200 and negative zeta potential was obtained. The encapsulation efficiency (EE%) was above 97% for both TML and CUR. Empty and co-encapsulated NLC showed in DSC and AFM characterization low recrystallization index and spherical shapes and were not cytotoxic for HaCaT cells, showing cell viability over 80% at the maximum concentration evaluated (1.48x1012 particles / ml, wich corresponds to 0.8 ?g / ml co-encapsulated TML / CUR). Furthermore, free and co-encapsulated TML / CUR showed high antioxidant activity in in vitro assays due inhibition of xanthine oxidation and pyrogallol autoxidation, indicating their potent superoxide dismutase inhibition even when co-encapsulated. The cosmetic emulgel was developed and physically stable after NLC incorporation in accelerated stability. Emulgel rheological profile showed a plastic and rheopexy characteristic, which remained storage stability. The rheological profile did not change due variations in the temperature analysis, indicating good formulation physical stability and cosmetic acceptability. The release profile of ECUR/TML release kinetics corresponded to the Higuchi model without influence of co-encapsulation with slower release of the encapsulated TML. Permeation data suggest that the active substances may permeate deep into skin. The actives permeability extent and intensity promoted by CLN will determine the applicability of the formulation that can be interest for the development of a cosmetic, dermocosmetic product or even for a transdermal drug. In conclusion, the developed CLN presented interesting physical and biological characteristics for topical application.
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