In recent years, the confocal and two photon microscopes have become ubiquitous tools in life science laboratories. The reason for this is that both these systems can acquire three dimensional image data from biological specimens. Specifically, this is done by acquiring a series of two-dimensional images from a set of equally spaced planes within the specimen. The resulting image stack can be manipulated and displayed on a computer to reveal a wealth of information. These systems can also be used in time lapse studies to monitor the dynamical behaviour of specimens by recording a number of image stacks at a sequence of time points. The time resolution in this situation is, however, limited by the maximum speed at which each constituent image stack can be acquired. Various techniques have emerged to speed up image acquisition and in most practical implementations a single, in-focus, image can be acquired very quickly. However, the real bottleneck in three dimensional imaging is the process of refocusing the system to image different planes. This is commonly done by physically changing the distance between the specimen and imaging lens, which is a relatively slow process. It is clear with the ever-increasing need to image biologically relevant specimens quickly that the speed limitation imposed by the refocusing process must be overcome. This thesis concerns the acquisition of data from a range of specimen depths without requiring the specimen to be moved. A new technique is demonstrated for two photon microscopy that enables data from a whole range of specimen depths to be acquired simultaneously so that a single two dimensional scan records extended depth of field image data directly. This circumvents the need to acquire a full three dimensional image stack and hence leads to a significant improvement in the temporal resolution for acquiring such data by more than an order of magnitude. In the remainder of this thesis, a new microscope architecture is presented that enables scanning to be carried out in three dimensions at high speed without moving the objective lens or specimen. Aberrations introduced by the objective lens are compensated by the introduction of an equal and opposite aberration with a second lens within the system enabling diffraction limited performance over a large range of specimen depths. Focusing is achieved by moving a very small mirror, allowing axial scan rates of several kHz; an improvement of some two orders of magnitude. This approach is extremely general and can be applied to any form of optical microscope with the very great advantage that the specimen is not disturbed. This technique is developed theoretically and experimental results are shown that demonstrate its potential application to a broad range of sectioning methods in microscopy.

Optical manipulation covers a wide range of techniques to guide and trap cells using only the forces exerted by light. Another optical tool is photoporation, the technique of injecting membrane-impermeable molecules using light, which has become an important alternative to other injection techniques. Together they provided sterile tools for manipulation and molecule delivery at the single-cell level. In this thesis, the properties of low Reynolds fluid flows are exploited to guide cells though a femtosecond Bessel beam. This design allows for high-throughput optical injection of cells without the need to individually target cells. A method of 'off-chip' hydrodynamic focusing was evaluated and was found to confine 95.6% of the sample within a region which would receive a femtosecond dose compared to 20% without any hydrodynamic focusing. The system was tested using two cell lines to optically inject the membrane-impermeable dye, propidium iodide. This resulted in an increase of throughput by an order of magnitude compared to the previous microfluidic design (to up to 10 cells per second). Next optical trapping and photoporation were combined to create a multimodal workstation. The system provides 3D beam control using spatial light modulators integrated into a custom user interface. The efficiency of optical injection of adherent cells and trapping capabilities were tested. The development of the system provides the groundwork for exploration of the parameters required for photoporation of non-adherent cells. Finally optical trapping is combined with temporally focused multiphoton illumination for scanless imaging. The axial resolution of the system was measured using different microscope objectives before imaging cells stained with calcein. Both single and a pair of recently trypsinised cells were optically trapped and imaged. The position of the trapped cells was manipulated using a spatial light modulator in order to obtain a z-stack of images without adjusting the objective position.

A crescente tendência de utilização de materiais austeníticos soldados e cladeados em componentes críticos em alguns setores industriais, como nas indústrias de óleo&gás e nuclear, leva a um aumento na demanda sobre ensaios não-destrutivos confiáveis na avaliação de sua integridade estrutural. Dentre os métodos utilizados na inspeção de soldas cladeados austeníticos estão os métodos de ultrassom por phased array, que são normalmente utilizados na detecção e localização de defeitos. No entanto, componentes com esse tipo de microestrutura são difíceis de inspecionar por phased array devido a anisotropia e inomogeneidade causadas pela microestrutura de grãos grosseiros que costumam levar ao aumento do nível de ruído, ao deslocamento de indicações e ao surgimento de indicações falsas. Sendo assim, a seleção de um método de phased array apropriado precisa levar em conta a habilidade do método em superar os problemas causados pela anisotropia e inomogeneidade. Esta tese apresenta dois métodos de imagem por phased array ultrassônico não-convencionais pensados como formas de ajudar na determinação da integridade de componentes onde soldas e cladeados austeníticos estão presentes. Ambos os métodos tem como base o método de foco total (TFM), sendo que o primeiro é uma extensão do método de leis de atraso adaptativas chamado Método de Foco Total de Atraso Adaptativo (ADTFM) e o segundo método usa fatores de coerência associado à imagens de TFM. A partir dos métodos de imagem aplicados é possível aumentar significativamente a qualidade das imagens por ultrassom em comparação com as imagens padrão obtidas por TFM, especialmente quando foi possível utilizar ambos os métodos combinados. / The increasing trend to use austenitic welded and cladded materials in critical components employed in some industrial sectors, such as the oil&gas and nuclear industries, leads to an increasing demand for their non-destructive assessment by reliable non-destructive methods. Among the methods used to access the integrity of austenitic welds and claddings are the Ultrasonic Phased Array methods, which are usually used to detect the presence and determine the position of defects. However, austenitic welds and claddings are challenging to inspect with Phased Array methods due to the anisotropy and inhomogeneity caused by their coarse grain microstructure, which is capable of increasing noise levels, misplace indications and create false indications. Therefore, the selection of an appropriate phased array method needs to take into account the method’s ability to overcome the impairment caused by anisotropy and inhomogeneity. This thesis presents two non-conventional methods based on ultrasonic phased array imaging techniques designed to assist the structural integrity assessment of components where austenitic welds and clads are present. Both proposed methods are based on the Total Focusing Method (TFM); the first approach is an expansion of the adaptive delay laws concept named Adaptive Delay Total Focusing Method (ADTFM), while the second method uses the coherence weights combined with the TFM images. From the imaging methods applied it was possible to significantly increase the quality of the ultrasonic images in comparison with the standard TFM, primarily when it was possible to combine both approaches.

O presente trabalho tem como objetivo principal a eletrofiação de nanofibras poliméricas de poliacrilonitrila (PAN) e polifluoreto de vinilideno (PVDF), incorporadas com negro de fumo (NF) e ftalocianina de cobre (CuPc), visando aplicações em dispositivos sensores. Inicialmente foram preparadas soluções de PAN puro a 6 % em peso e PVDF puro a 20% em peso e foram misturadas a essas soluções partículas de negro de fumo e ftalocianina de cobre, obtendo soluções de PAN/NF, PVDF/NF, PAN/CuPc e PVDF/CuPc. Foi determinada a viscosidade absoluta das soluções. Realizou-se a eletrofiação para obtenção de nanofibras que foram caracterizadas segundo o diâmetro e morfologia, usando microscópio óptico e microscópio eletrônico de varredura. Para avaliar as interações polímero-polímero, polímero-partícula foram analisadas por espectroscopia FITR e Raman. Com as fibras de PAN/NF foi analisada a resistência e condutância elétrica das membranas usando um picoamperímetro digital, visando aplicação como filtro eletrostático. Foi construído canal na lâmina de silício usando um feixe de laser visando a deposição de fibras dentro do canal usando a técnica de focagem eletrodinâmica com tensão aplicada em máscaras de cobre. Foi usada a técnica da microbalança de cristal de quartzo para determinar a variação de massa adsorvida por membranas de PAN/CuPc e PVDF/CuPc por meio da medida da variação de frequência usando um frequencímetro digital, onde se observou que essas membranas são promissoras para atuar como sensores de vapor de amônia. / The main objective of this work is the incorporation of different particles in order to electrospun polymeric nanofibers of polyacrylonitrile (PAN) and polyvinylidene fluoride (PVDF), aiming at applications in sensor devices. Initially, solutions of PAN pure 6 wt% and PVDF pure 20 wt% were prepared and these solutions were mixed with carbon black (NF) particles and copper phthalocyanine (CuPc), obtaining solutions of PAN/NF, PVDF/NF, PAN/CuPc and PVDF/CuPc. The absolute viscosity of the solutions was determined. The electrospinning was performed to obtain nanofibers that were characterized according to the diameter and morphology, using optical microscope and scanning electron microscopy. To evaluate the polymer-polymer and polymer-particle interactions, FITR and Raman spectroscopy were performed. The resistance and conductance of the membranes electrospun from PAN/NF solution were analyzed using a digital picoammeter, and an increase in the resistance was measured. This result shows that the membrane is suitable to be applied as electrostatic filter. A channel was constructed on the silicon wafer using a laser beam for the deposition of fibers inside the channel using the electrodynamic focusing technique. The quartz crystal microbalance technique was used to determine the applicability of the membranes as sensor layer. The results of PAN/CuPc and PVDF/CuPc membranes suggests that these membranes are promising to act such as ammonia vapor sensors.

A pobreza na América Latina e seu enfrentamento têm demandado esforços dos governos e ocupado espaço nos debates acadêmicos. A via escolhida por muitos governos para esse enfrentamento tem sido a utilização dos Programas de Transferência Condicionada de Renda, os quais se utilizam da via da focalização visando atender às famílias em situação de pobreza e de extrema pobreza. O presente trabalho procurou analisar esses programas, os quais foram adotados pelos governos do Brasil e do México, respectivamente os programas Bolsa Família e Oportunidades. Tem como objetivo geral analisar os desenhos dos programas com seus mecanismos de elegibilidade e como objetivos específicos analisar a possível interferência de tais mecanismos no alcance da máxima cobertura do publico alvo, além de analisar também a forma como ocorre o cadastramento das famílias nos dois programas. Para tanto, foi utilizado um estudo comparativo entre os dois programas por meio de pesquisa bibliométrica e documental revisando a literatura a respeito e consultas a documentos governamentais e institucionais, além de relatórios encomendados por instituições internacionais a exemplo do Banco Mundial. A pesquisa encomendada pelo Banco Mundial e realizada por Castañeda e Lindert (2005), norteou o que se refere às características dos programas estudados, como se dá a focalização em cada um, seus mecanismos de elegibilidade e os cuidados requeridos desde a concepção do programa, passando pela sua implementação até chegar ao monitoramento e avaliação dos mesmos. Os programas Bolsa Família e Oportunidades possuem algumas características comuns e outras divergentes entre si. Promoveram ganhos redistributivos e lograram considerável benefício às famílias beneficiadas, porém apresentaram vazamentos decorrentes de erros de focalização, o que contribuiu para o não atendimento ao contingente total de famílias elegíveis, de modo que os limites orçamentários dos programas não chegaram a ser o único fator causador dessa cobertura insuficiente, uma vez que os vazamentos também foram determinantes. A importância e visibilidade dos programas e a incompletude dos dados sugere a necessidade de se ampliar e atualizar as informações sobre este tema que se apresenta como uma via bastante interessante de combate à pobreza e extrema pobreza, apontando para as análises das novas conjunturas políticas, sociais e econômicas. / Poverty in Latin America and its confrontation have demanded governments\' efforts and occupied space in academic debates. The path chosen by many governments for this confrontation has been the use of Conditional Income Transfer Programs, which use the targeting approach to assist families living in poverty and extreme poverty. The present work sought to analyze these programs, which were adopted by the governments of Brazil and Mexico, respectively the Bolsa Família and Oportunidades programs. Its general objective is to analyze the designs of the programs with their eligibility mechanisms and as specific objectives to analyze the possible interference of such mechanisms in the reach of the maximum coverage of the target public, as well as to analyze how the registration of the families in the two programs occurs. To do so, a comparative study was used between the two programs by means of bibliometric and documentary research, reviewing the literature on the subject and consultations with governmental and institutional documents, as well as reports commissioned by international institutions such as the World Bank. The research commissioned by the World Bank and conducted by Castañeda and Lindert (2005), guided the characteristics of the programs studied, how to focus on each one, its eligibility mechanisms and the care required from the conception of the program, through its implementation to the monitoring and evaluation of the same. The Bolsa Familia and Oportunidades programs have some common and other divergent characteristics. They promoted redistributive gains and achieved a considerable benefit to the beneficiary families, but they showed leaks due to errors of focus, which contributed to the non-attendance to the total contingent of eligible families, so that the budgetary limits of the programs did not become the only causal factor insufficient coverage, since the leaks were also decisive. The importance and visibility of the programs and the incompleteness of the data suggest the need to expand and update the information on this topic is a very interesting way of combating poverty and extreme poverty, pointing to the analyzes of the new political conjunctures, social and economic.

No description available.

La technologie de la microencapsulation comprend généralement deux procédés : les procédés de production de microgouttes/microémulsions et les procédés de leur encapsulation. A cause de difficultés de calibrer la taille de microgouttes, des microcapsules ont souvent une grande dispersion sur leur taille. La technologie microfluidique permet d'améliorer la monodispersité de microcapsules.<br />Cette thèse a pour objet la conception et la réalisation d'un système microfluidique pour la production de gouttes calibrées et leur encapsulation. La contribution de cette thèse consiste en trois aspects : le premier concerne les effets géométriques sur la formation de goutte ; le deuxième concerne la dynamique des écoulements, le comportement d'écoulement laminaire, les propriétés physico-chimiques des couples diphasiques sur la taille de gouttes, les lois corrélant la taille de gouttes. Troisièmement, un système microfluidique est conçu dans lequel le procédé complet de la microencapsulation est réalisé pour la fabrication de microcapsules monodisperses. Les perspectives d'applications sont nombreuses.

- An extensive summary in French is available in Appendix E on page 189 -

<p>Affective forecasting refers to the process of predicting future emotions in response to future events. The overall aim of the present thesis was to investigate, by applying the framework of Affective forecasting, how car users predict their satisfaction with public transport services. Study 1, Part 1 revealed a satisfaction gap between users and non-users of public transport, whereby non-users reported lower satisfaction than users, in overall satisfaction as well as in two quality factors resulting from a factor analysis of a major survey on satisfaction with public transport. It was hypothesized that non-users were biased in their satisfaction reports, something which was subsequently investigated in Study 1, Part 2, where a field experiment revealed that car users suffer from an impact bias in their predictions about future satisfaction with public transport due to being more satisfied with the services after a trial period than they initially predicted they would. Addressing the question of whether or not a focusing illusion is the psychological mechanism responsible for the impact bias, two experiments containing critical incidents were conducted during Study 2, in order to investigate whether or not car users exaggerate the impact of specific incidents upon their future satisfaction with public transport. For car users with a stated intention to change their current travel mode, in Study 2, Part 1, as well as for car users with no stated intention to change their travel mode, in Study 2, Part 2, the negative critical incident generated lower predicted satisfaction with public transport, in support of the hypothesis that the impact bias in car users’ predictions about future satisfaction with public transport is caused by a focusing illusion.</p>

The present study is an empirical phenomenological investigation of the influence of peer group Focusing practice (Gendlin, 1981) on doctoral psychology students' senses of their developing clinical expertise. Focusing, a therapeutic bodily awareness and symbolization practice, was proposed as a method that would support the development of student self-reflection, self-assessment, and self-care. The present study investigates the experiences of three female doctoral students who participated in a peer-initiated and peer-run Focusing group for five semesters. The methodological procedures for a reflective empirical phenomenological study as articulated by Giorgi and Giorgi (2003), Robbins (2006), and Wertz (1984) were followed. Procedures adapted from Walsh (1995) to ensure phenomenological researcher reflexivity and to explicate the researcher's approach to the phenomenon were also used. All participants provided data via audiotaped individual interviews, read provisional interpretations and provided written and verbal feedback to the researcher. The interpretive analyses of these texts indicated that all participants found their participation in the peer Focusing group to enhance some aspects of their clinical expertise. The findings support the idea that peer group Focusing is a helpful method for directly training psychology graduate students in self-reflection, self-assessment, and self-care. Relationships between these findings and research on the use of mindfulness meditation in graduate psychology training are discussed. Implications for curriculum development, including a discussion of the relationship between the findings and the training concepts of personal professional development and professional development are explored. / McAnulty College and Graduate School of Liberal Arts / Clinical Psychology / PhD / Dissertation