Approved for public release, distribution is unlimited / This thesis study focuses on understanding the dissipation processes of the stratocumulus deck after sunrise. This objective is met through careful analyses of observational data as well as model simulations. Measurements from the Marine Atmosphere Measurement Lab (MAML) of the Naval Postgraduate School (NPS) are used in this study. In particular, the half-hourly wind profiler/Radio Acoustic Sounding System (RASS) measurements were used to determine the boundary layer top and the evolution of the boundary layer mean thermodynamic properties during the cloud breakup period. Measurements from a laser ceilometer and the routine surface measurements are also used to detect the variation of cloud base height, the evolution of the cloud deck, and the onset of sea breeze. These measurements revealed the increase of the boundary layer depth after sunrise followed by a decrease of the boundary layer depth after the onset of the sea breeze, which points to the role of surface heating and sea breeze development in modulating cloud evolution. The effects of surface heating and sea breeze are further tested using a 1-dimensional mixed layer model modified for coastal land surfaces. / Lieutenant Commander, United States Navy

Graphical information presented as pictures, graphs, maps, and the like are an important media for relaying knowledge and are a fundamental means of education rarely experienced by people who are blind or have a severe visual impairment. This thesis presents the design, development and testing of a multiple finger, haptic matrix dynamic display device capable of relaying graphical information through simulated textures. The design is based on user perception studies that determined which hand constraints provided the best tradeoff between simplicity of design, accuracy and time to answer. The best design was one that incorporated multiple fingers in close proximity to each other and restricted wrist rotation. Upon further testing after the development of the device, evidence was gathered to show its effectiveness. Although subjects could determine key information from the simulated textures, there is a clear mismatch between the simulated representations of the objects and their tactile or embossed counterparts. There is some evidence that shows that the spatial resolution of the actuators may be a source of this error and also some evidence to state that it is the inability to track the edges that causes the difference between determining the physical diagrams and the simulated. On the other hand, results on determining locations using simulated maps were far closer to the control texture maps used than the results for object diagrams. Further studies could be done to determine the effect of higher actuator spatial resolution on object identification and edge tracking.

This thesis focuses on inductive base sensor design at MHz range frequency. The background theory, design, experiments and results for a new magnetic particles sensor is presented. A new magnetic sensor based on a planar coil was investigated for DNA pathogen detection. Change in inductance of the planar coil due to the presence of magnetic particles with varying mass was measured. The experimental set-up consisted of different sized planar coil with associated electronics for inductance measurements. The best sensor performance was accomplished using two different inductors while oscillating at frequencies 2.4MHz using 9.5μH inductor and 7.2MHz with 85μH inductor. The sensor has very large signal to noise ratio (580×103), while the average amount of frequency drift was 0.58. This sensor was tested with various types of magnetic particles. In addition, iron-oxide nanoparticles were synthesized through water in oil microemulsion method and with an average size of 25nm. The best sensitivity achieved for detection of 50μg iron-oxide particles was with the bead size of 10nm. 81Hz frequency shift was attained in regard to that amount of particles. This research shows that increasing the resonance frequency to 7.2MHz can cause the larger output signal difference (frequency shift) in the presence of magnetic particles; however, the sensor stability is the most important factor for determining the detection resolution and sensitivity. The sensitivity is better if the sensor can detect smaller amount of magnetic sample. The results of this research demonstrate that while the sample consists of smaller size particles, the sensor can detect the lower amount of sample. This is due to the heating effect of nanoparticles. On the other hand the sample distance from the sensor has a major impact on the sensitivity too; the shorter the distance, the higher the sensitivity. This technique can potentially be extended to detect several different types of bacterial pathogens and can be modified for multiplex quantitative detection. This sensing technique will be incorporated into a handheld, disposable microfluidic chip for point-of-care diagnostics for sexually transmitted diseases.

Au cours du stockage et sous de mauvaises conditions de conservation, les grains de blé peuvent subir diverses altérations causées par le développement fongique. Les moisissures peuvent produire des toxines pouvant avoir un impact sur la santé du consommateur. L’évaluation de la diversité fongique sur blé de stockage produit localement dans les régions céréalières du Nord de la Tunisie durant deux années successives (2010-2011 et 2011-2012) a montré une dominance du genre Alternaria. L’étude de la cinétique d’évolution de cette mycoflore au cours du stockage s’est caractérisée par un profil particulier dépendant des paramètres géographiques et temporels et des conditions écophysiologiques. L’évaluation du pouvoir toxinogène a révélé un faible pourcentage d’isolats ochratoxinogènes. L’évaluation de la présence de l’OTA dans le blé ont montré des taux de contaminations largement inférieurs aux normes européennes. L’étude sur la physiologie de sporulation et la production d’OTA en Fermentation en Milieu Solide par A. carbonarius à montré une amplification de la production des conidiospores et de l’OTA par aération humide forcée. L’évaluation de l'activité antifongique de 15 bactéries lactiques isolées du blé de stockage à l’égard de 8 moisissures post-récolte a montré une bonne aptitude de Lb. plantarum à inhiber la croissance de ces moisissures. L’étude du pouvoir anti-ochratoxinogène de Lb. plantarum LabN10, Lb. graminis LabN11 and P. Pentosaceus LabN12 ont montré un effet significatif de la température, du pH et de la biomasse bactérienne sur l’inhibition de la biomasse fongique ainsi que sur la réduction d’OTA. / During storage and under bad storage conditions, wheat grains can undergo various alterations caused by fungal growth. Molds can produce toxins that can have an impact on consumer health. Assessment of fungal diversity on wheat storage locally produced cereal in northern Tunisia during two successive years (2010-2011 and 2011-2012) showed a dominance of the genus Alternaria. Study of kinetics evolution of mycoflora during storage is characterized by a particular pattern depending on geographic and temporal parameters and ecophysiological conditions. Evaluation of toxigenic fungal revealed a low percentage of ochratoxinogenic isolates. Occurence of OTA in wheat showed contamination levels under European standards. The study on sporulation physiology and production of OTA by Solid State Fermentation by A. carbonarius shown amplification and production of conidiospores OTA wet forced by aeration. The evaluation of the antifungal activity of lactic acid bacteria (LAB) isolated from the 15 wheat storage against 8 post-harvest molds showed good ability of Lb. plantarum to inhibit the growth of these fungi. The study of anti-ochratoxinogène activity Lb. LabN10 plantarum, Lb. and P. graminis LabN11 LabN12 pentosaceus showed a significant effect of temperature, pH and the bacterial biomass on the inhibition of the fungal biomass and on the reduction of OTA.

Após a constatação da escassez de estudos realizados com vegetais crus na busca por novas estirpes de bactérias láticas (BAL) produtoras de bacteriocinas e diante do potencial tecnológico da aplicação destas cepas tanto como agentes de conservação em alimento, bem como cultura probiótica em alimentos funcionais, este estudo objetivou isolar e identificar cepas de bactérias láticas potencialmente bacteriocinogênicas de amostras de rúcula obtidas no comércio local de São Paulo, SP - Brasil, identificar e caracterizar as bacteriocinas produzidas pelos isolados e avaliar o potencial probiótico dos isolados testando sua sobrevivência no modelo dinâmico do trato gastrointestinal TNO gastro-Intestinal Model - TIM-1 disponível no TNO (The Netherlands Organization for Applied Scientific Research) divisão Quality of Life (Zeist, Holanda). A produção de bacteriocinas neste modelo também foi avaliada, comparando-se com L. sakei 2a, também produtora de bacteriocinas e ainda avaliou-se a interferência na viabilidade de E. faecium LMA1. A cepa Lactococcus lactis subsp. lactis MK02R de rúcula produziu uma bacteriocina sensível à enzimas proteolíticas, termoestável e não influenciada pelo pH, sendo capaz de inibir Enterococcus faecium, Lactobacillus sakei, Listeria innocua, Lactobacillus delbrueckii e Listeria Monocytogenes de diferentes grupos sorológicos. Os ensaios genéticos utilizando primers Nisf e Nisr confirmaram que a bacteriocina MK02R é uma nisina, apresentando uma alteração dos aminoácidos no peptídeo líder em relação às nisinas A, Z, Q, F e U, porém com a estrutura do peptídeo maduro idêntica ao da nisina F. Estes resultados foram confirmados por espectrometria de massas de amostras purificadas por HPLC. L. lactis MK02R resistiu à passagem no modelo dinâmico TIM-1, apresentando uma alta capacidade de sobreviver nas condições simuladas do trato gastrointestinal humano. Entretanto, não foi capaz de causar a redução no número de E. faecium LMA1. Em contrapartida, L. sakei 2a, mesmo apresentando uma sobrevivência menor, foi capaz de causar uma redução de 70% na população de E. faecium LMA1 no ambiente simulado do TGI. Não foi detectada atividade residual da ação antimicrobiana das bacteriocinas produzidas por L. lactis MK02R ou L. sakei 2a após a passagem pelo modelo dinâmico TIM-1. Estes resultados evidenciam a possível aplicação de L. lactis MK02R como um agente de controle biológico na conservação de alimentos e também como uma cultura potencialmente probiótica. / Given the scarcity of studies performed with raw vegetables addressing the search for new bacteriocinogenic strains of lactic acid bacteria (LAB) and considering the technological application of these strains as food preservatives and probiotic cultures in functional foods, this study was aimed at isolation and identification of bacteriocinogenic LAB strains from samples of rocket salad obtained in the local market of São Paulo, SP - Brazil, subsequent characterization of the bacteriocins produced by these LABs and evaluation of their probiotic potential by testing their survival in the dynamic gastrointestinal model TNO gastro- Intestinal-Model - TIM-1, available at the TNO (Netherlands Organization for Applied Scientific Research) Quality of Life division (Zeist, Netherlands). The studies in the TIM-1 model were also done with another bacteriocinogenic strain L. sakei 2a for comparison, evaluating their interference on the viability of E. faecium LMA1. The bacteriocin produced by strain Lactococcus lactis subsp. lactis MK02R isolated from rocket salad was sensitive to proteolytic enzymes, heat-stable and not influenced by the pH. The bacteriocin inhibited the growth of Enterococcus faecium, Lactobacillus sakei, Listeria innocua, Lactobacillus delbrueckii the primers Nisf and Nisr indicated that the bacteriocin produced by the strain MK02R is a nisin, with a change in the amino acid sequence of the leader peptide when compared to nisin A, Z, Q, U and F, but with the structure of the mature peptide homologous to that of nisin F. These results were confirmed by mass spectrometry of purified samples obtained by HPLC. L. lactis MK02R withstood the test in the dynamic model TIM-1, presenting capability to survive in the simulated conditions of the human gastrointestinal tract. However, the strain was not able to cause a reduction in the number of E. faecium LMA1. On the other hand, L. sakei 2a, even presenting lower survival, was able to cause 70% reduction in the population of E. faecium LMA1 in the gut simulated environment. No residual antimicrobial activity of bacteriocin produced by L. lactis MK02R or L. sakei 2a was detected after the transit through the dynamic model TIM-1. These results demonstrate the possible application of L. lactis MK02R both as a biocontrol agent in food preservation and as a potentially probiotic culture.

The diploma thesis focuses on support of teaching in chosen subjects in the second year of elementary school using interactive white boards with new technology SMART lab. It is focused on evaluation of publicly available interactive teaching portal applications, which occurre in high numbers, however they are obsoled or inappropriately created. Subsequently, the thesis includes a research which pays attention to the usage of the interactive white boards in chosen subjects in the second year of elementary schools located in Vysočina region. The main aim is to ascertain knowledge of teachers when using this technology. The examined subjects were chosen of the result of the questionnaire survey which was sent to teachers from the first grade of the elementary school.

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No. of bitstreams: 1 Lucas de Vasconcelos Teixeira.pdf: 30069920 bytes, checksum: 7e644d5de1b68f899254e06965368c86 (MD5) Previous issue date: 2016-03-17 / The theme of this academic research is the Cafés, as communicational environments of sociability and consumption of memories and experiences. Its theoretical object is the consumption of memories and experiences, spatialities and temporalities of Cafés in the city of São Paulo, while the empirical objects are Café Girondino and Coffee Lab, which allow us to observe a variety of cultural scenes involving the universe of coffee. The general objective of this study is to examine the phenomenon of cultural scenes in the city of São Paulo, originated from the consumption of memories and experiences in communicational spaces and sociability, as observed at the Cafés mentioned above. One of its specific objectives is to analyze to what extend Café Girondino, nowadays, operates as a space organized by communicative strategies, enabling to revisiting memories and histories that took place at the beginning of modernity in the city of São Paulo, mainly at the end of the XIX century and the beginning of the following century. In addition to that, to identify how Coffee Lab disseminates the culture of specialty coffees, counting on a pedagogy of consumption, and becomes an obligatory destination for coffee lovers. Furthermore, we aim to problematize similarities and differences involving these cultural scenes including here the consumption of memories and experiences in these two Cafés. The guiding issue is to understand how these cultural scenes rise and structure with the consumption of memories and experiences in these iconic Cafés in the city of São Paulo. The corpus of this study includes the physical spaces of both Cafés, their objects, interviews and courses. For a deeper investigation into these communicational environments, we employed the flânerie methodology, as proposed by McLaren (2000), grounded on bibliographical and documentary researches. Among the theoretical references, authors as Will Straw, Norval Baitello, Mary Douglas and Baron Isherwood, Walter Benjamin, Iúri Lótman, Maurice Halbwachs, Pierre Nora, Mike Featherstone, Mônica Nunes, Cláudia Pereira, Vander Casaqui, Ana Luiza Martins and Nicolau Sevcenko, not to mention other thinkers that have contributed to our discussions. The results show there is a media strategy in these spaces, and the symbolic meaning that brings reasoning and value to consumptions is the fruit of sociabilities that go beyond market studies, characterizing these cultural scenes as a symptomatic phenomenon. / Esta pesquisa tem como tema os Cafés como ambiências comunicacionais de sociabilidade e de consumo de memórias e experiências. O objeto teórico diz respeito ao consumo de memórias e experiências, de espacialidades e temporalidades em cafeterias paulistanas, enquanto que os objetos empíricos são o Café Girondino e o Coffee Lab, que permitem observar variadas cenas culturais envolvendo o universo do café. O objetivo geral é examinar o fenômeno das cenas culturais paulistanas originadas do consumo de memórias e experiências em espaços comunicacionais e de sociabilidade, como nas referidas cafeterias. Os objetivos específicos são: analisar em que medida o atual Café Girondino opera como um espaço que se organiza através de estratégias comunicativas que proporcionam revisitar memórias e histórias do início da modernidade paulistana, mais precisamente do final do século XIX e início do seguinte; identificar as formas pelas quais o Coffee Lab dissemina a cultura dos cafés especiais por meio de uma pedagogia do consumo e se converte em destino obrigatório para os apreciadores da bebida; problematizar as semelhanças e diferenças entre as cenas culturais e também entre os consumos de memórias e experiências nas duas cafeterias. A questão que norteou a pesquisa pretende responder de que modo são constituídas as cenas culturais que se articulam em torno do consumo de memórias e experiências nestas cafeterias paulistanas icônicas. O corpus de pesquisa inclui os espaços físicos de ambas as cafeterias, seus objetos, entrevistas e cursos. Para melhor explorar estas ambiências comunicacionais, utilizamos a flânerie de McLaren (2000) como a metodologia aplicada, alicerçada por pesquisas bibliográfica e documental. O referencial teórico inclui autores como Will Straw, Norval Baitello, Mary Douglas e Baron Isherwood, Walter Benjamin, Iúri Lótman, Maurice Halbwachs, Pierre Nora, Mike Featherstone, Mônica Nunes, Cláudia Pereira, Vander Casaqui, Ana Luiza Martins e Nicolau Sevcenko, entre outros pensadores que contribuem para as discussões. Os resultados indicam que há uma estratégia midiática de construção desses espaços ao mesmo tempo em que as apropriações que dão sentido e valor ao que é consumido são fruto de sociabilidades que ultrapassam o que é mercadologicamente planejado, sendo as cenas culturais seu fenômeno sintomático.

Como a experiência estética pode ampliar as condições de escuta, leitura e compreensão do mundo? O objetivo desta pesquisa é trazer à luz o campo da criação artística como analogia da construção sensível do ser humano e a constituição de sua visão de mundo. Espera-se poder refletir sobre como o trabalho artístico se relaciona com processos subjetivos, conduzindo à transformação de aspectos psicológicos. Tomaremos a abordagem do Construtivismo Semiótico-Cultural em Psicologia como possibilidade de mediação de um diálogo entre Artes Cênicas e Psicologia, para a compreensão de processos e modos híbridos de criação, com o intuito de poder contribuir com procedimentos que abarquem estratégias de intervenção em Psicologia. Utilizaremos como material empírico os registros da atividade artístico-pedagógica do pesquisador que atua como artista-orientador do Programa Vocacional da Prefeitura da cidade de São Paulo. A forma de análise dos resultados prezará pela compreensão do acontecimento artístico em sua interdependência e interrelação com a pessoa e inserida dentro de seu campo social. São feitas reflexões sobre os procedimentos do processo de criação que envolve a elaboração de protocolos, depoimentos, entrevistas, ações culturais, construção de cenas como produtos artísticos que aparecem, ressoam e ressignificam a vida cotidiana. Consideramos que a experiência vivida da criação artística funde-se a uma pessoa também em construção, que vivencia, num espaço-tempo codificado, outras possibilidades e relações, percebe no advento do artifício sua incompletude como potencialidade latente de reinventar sua própria realidade / How can aesthetic experience enhance the conditions of listening, reading and understanding of the world? The objective of this research is to bring to light the field of artistic creation as an analogy of the sensitive construction of human being and his/her worldview constitution. It is expected that we can reflect on how the artistic work relates to subjective processes, which leads to the transformation of psychological aspects. We will take the approach of Semiotic- Cultural Constructivism in Psychology as the possibility of mediation of a dialogue between Performing Arts and Psychology, in order to understand of processes and hybrid forms of creation, intending to being able to contribute to procedures that cover strategies of intervention in Psychology. As empirical material, we will use the researchers who works as a tutor-artist in the Vocational Program of the city of Sao Paulo artistic-pedagogical activity records. The form of analysis of the results will focus the understanding of the artistic happening in its interdependence and interrelationship with the person, and inserted within his/her social field. We reflect on the procedures of the creation process that involves the elaboration of protocols, testimonies, interviews, cultural actions, and the construction of scenes as artistic products that appear, resonate and resignify day-to-day life. We consider the lived experience of artistic creation merges with a person who is also under construction, who experiences, in a codified space-time, other possibilities and relations, perceives in the advent of artifice his/her incompleteness as latent potentiality to reinvent his/her own reality

Nos estudos dos ritmos biológicos de roedores em laboratório, a roda de atividade é comumente utilizada assumindo-se que o horário da atividade em roda represente o horário de atividade do animal na natureza. Entretanto, a atividade de qualquer espécie pode ser diferente em campo e em laboratório, e tampouco se resume à atividade em roda. O tuco-tuco (Ctenomys aff. knighti) é um roedor subterrâneo diurno em campo e noturno em laboratório. Por isso, o nosso primeiro objetivo é verificar quais comportamentos são apresentados pelos tuco-tucos em laboratório, a distribuição desses comportamentos ao longo do dia e qual a contribuição da atividade em roda para o total de sua atividade e ritmicidade. O segundo objetivo é verificar quais os efeitos agudos (mascaramento) que a luz e a escuridão têm sobre a atividade dos tuco-tucos, dado que costumam ter efeitos opostos (exacerbação/inibição) em animais diurnos e noturnos. 18 machos e fêmeas adultos (150-250g) foram mantidos em gaiolas individuais e tiveram sua atividade em roda monitorada por registro automatizado, atividade geral monitorada por sensores de infravermelho e por acelerômetros, temperatura corpórea monitorada por transmissores telemétricos e comportamentos de laboratório registrados por câmeras filmadoras. Eles foram submetidos a um regime de CE 12:12 (C= 100 lux) por sete dias para que seus ritmos se sincronizassem com esse ciclo pelo mecanismo de arrastamento. Depois, receberam um pulso de luz durante a noite e, dois dias depois, um de escuridão durante o dia, para verificar se há efeito de mascaramento de seus comportamentos por luz e escuridão. Cada animal passou por esse mesmo protocolo em três condições: na primeira, sem roda de atividade; na segunda, com roda; na terceira, com roda travada. A maioria dos animais demonstrou pouca ou nenhuma ritmicidade em comportamentos específicos de laboratório que não a atividade em roda, a qual também é o principal componente da atividade geral a sofrer efeitos agudos de pulsos de luz. Um único indivíduo, quando mantido sem roda de atividade, mudou de noturno para diurno. Como a atividade em roda foi o principal comportamento inibido pela luz, cujo efeito foi quase nulo nos demais comportamentos, o mascaramento parece não ser um empecilho para a atividade diurna do tuco-tuco em campo, apesar do mascaramento ser considerado um desafio à inversão de noturnalidade para diurnalidade tanto na escala de vida individual quanto evolutiva / The running wheel is commonly used in rhythm studies assuming that the wheel-running time corresponds to the activity time in nature. The tuco-tuco (Ctenomys aff. knighti) is a subterranean rodent which is diurnal in the field and nocturnal in the lab. Because of that peculiarity, our first goal is to verify which are their behaviors in the lab, their distribution throughout the 24 hours, and how much the running wheel activity contributes to the total activity and its rhytmicity. The second goal is to verify the acute effects of light and darkness on their rhythms. 18 adult males and females (150-250g) had their behaviors recorded by cameras. Their running wheel activity, general activity and body temperature were also monitored. They were kept in a LD 12:12 (L = 100 lux) regimen and received light and darkness pulses to verify possible masking effects in their rhythms, going through the same protocol three times: 1) without wheel, 2) with wheel, and 3) with a blocked wheel. Most of animals demonstrated little to no rhythmicity in specific lab behaviors, except for running wheel activity. The wheel activity is also the main component of the general activity that is inhibited by the light pulse, but we found some masking on body temperature rhythm as well. Interestingly, there was a single individual that switched from nocturnal to diurnal when kept without a running wheel, and presented the masking patterns expected for diurnal animals. As wheel activity was the main component suffering inhibition by light, with little to no inhibition of other behaviors, it seems masking isn\'t an obstacle to the diurnal activity in the field and consequently to switches from nocturnal to diurnal activity within an individual lifetime or even in evolutionary scale for tuco-tucos

L’objectif de ce travail porte sur l’étude et la réalisation de résonateurs optiques à état liquide en microfluidique digitale. Les gouttes sphériques constituent des résonateurs à mode de galerie, dans lesquels la lumière peut être piégée par réflexion totale interne. A l’échelle microscopique, elles exhibent des propriétés optiques remarquables. Leurs facteurs de qualité très élevés en font notamment des objets propices à l’étude de phénomènes optiques non linéaires, tel l’effet laser, et leur confèrent un potentiel certain en spectroscopie. Par ailleurs, la microfluidique digitale, qui a trait aux systèmes multiphasiques dans des microcanaux artificiels, offre une grande liberté de manipulation des microgouttes : génération au kHz, transport, encapsulation, fusion, division, stockage, triage… Aussi, pour les laboratoires-sur-puce, le développement de ces microgouttes en cavités résonantes constitue une opportunité d’intégrer des outils d’analyse optique capables de sonder des échantillons allant du picolitre au nanolitre.Après un exposé des propriétés optiques des résonateurs à modes de galerie, ce mémoire rapporte les travaux réalisés. Une présentation des méthodes de microfabrication et du montage expérimental précède l’étude de la génération de cavités optiques liquides en dynamique. Ces cavités résonantes sont ensuite appliquées aux sources lasers microfluidiques. En particulier, un effet laser a été mis en évidence dans des microgouttes sphériques d’éthylène glycol contenant de la rhodamine 6G. Enfin, une ouverture sur des systèmes couplant microgouttes et cavités Fabry-Perot présente d’autres perspectives telles que l’analyse de gouttes passives en intravité laser ou bien la commutation rapide de la longueur d’onde d’émission de lasers microfluidiques monomodes. / The purpose of this work is to study and realize liquid state optical resonators in digital microfluidics. Spherical droplets may behave as whispering gallery mode resonators, in which light is trapped by total internal reflections. At the microscopic scale, they exhibit outstanding optical properties. Their high quality factors make them attractive for studying non-linear optical phenomena, such as lasing, and for spectroscopy. In another field of research, digital microfluidics, that deals with multiphase fluid systems in artificial microchannels, also involves microdroplets. It offers a high degree of freedom in handling microdroplets: kHz generation, transport, encapsulation, fusion, division, stockpiling, sorting… Therefore, in lab-on-chip systems, turning microdroplets into resonant microcavities constitutes an opportunity for integrating optical analysis tools that can probe picoliter to nanoliter samples.After a review of the optical properties of whispering gallery mode resonators, this thesis reports the experimental results. A presentation of the methods of microfabrication and of the experimental bench top precedes the study of the dynamic generation of liquid optical microcavities. Then, these resonant cavities are applied to microfluidic laser sources. In particular, lasing effect has been demonstrated in spherical microdroplets of ethylene glycol and rhodamine 6G. Finally, an opening towards systems that combine microdroplets and Fabry-Perot cavities presents other perspectives such as the analysis of passive droplets in laser intacavity or the capability of fast switching the output wavelength of single mode microfluidic dye lasers.