In this thesis I study the role of artificial lighting in the everyday urban life of older residents living in the London Borough of Newham. Newham's light infrastructure is currently undergoing change as the borough's entire 19,000 street lamps are being re-placed with Light Emitting Diodes and as a range of regeneration projects provide public spaces designed with new lighting. By increasing visibility and encouraging everyday activity into the evening, the Council claims that the changes in public light-ing will provide 'eyes on the streets' and encourage 'eyes from the windows' of build-ings, contributing to increasing 'natural surveillance'. The Council's avowal of every-day practices in streets and in homes, has made me question how lighting affects the way older residents move through streets and carry out domestic practices as dark-ness falls. The study explores how light planning, lighting design and everyday, rou-tine practices in the public realm and inside homes co-produce the urban, lit environ-ment. Two major contributions of the thesis lie in the (post)phenomenological ap-proach I develop to study everyday experiences of urban lighting, and the methodo-logical framework I employ to research such practices, which combines mobile and visual methods. I have conducted 11 in-depth interviews with nine different planners and designers, 12 walk-along interviews with 22 residents between 58 and 79 years old, and a collaborative photography project with 14 residents between 68 and 96 years old. As I show how older residents experiences different lighting technologies, layers of light, and different lit spaces in their neighbourhoods, I discuss how urban lighting makes them see, feel and carry out routine practices in particular ways. Based on my findings, I argue that urban lighting shapes what, and how, people see, but how people see depends on how they negotiate changes in lighting. In a range of examples where residents mould the urban, lit environment or respond to lighting in different ways, I show how they play and active part in co-producing ways of seeing. I argue it is crucial that light planners and lighting designers recognise such co-constitutive role of everyday practices in order to ensure better lighting for our future cities.

This research project consists of a critical analysis of the role of intellectual property amongst other factors in the successful commercial development at the Cavendish Laboratory of optoelectronic light emitting diode display devices based on novel organic semiconductor materials. It begins by giving the background to the quantum mechanical properties upon which the technology is based, followed by a discussion of the path of innovation, describing the interaction between the different socioeconomic factors that influence this path. It then draws an analogy with the development of an analogous technology - inorganic semiconductors - to signpost the factors that may affect the developmental history of the technology. This is followed by an analysis of a chronology derived initially from patents downloaded from the World Patents Database of the European Patent Office to showcase the technology's development steps, and to study the patenting strategy of Cambridge Display Technology (CDT) - the company that was set up to commercialise the novel technology - through a patent trends analysis. From that, the major socioeconomic factors critical to the technology's development are analysed, followed by a test and extension of an existing Black Box mathematical model for studying the dynamics of innovation that is based on the interaction of those factors. Finally, through a patent citation analysis, CDT's commercial strategy for the technology is shown as being based on its patents portfolio to build an extensive licensing programme that pooled major academic, industry and commercial partners for the furtherance of the technology. This later evolved into a new ecosystem for the innovation, of which CDT occupied a central and indispensable position.

>Magister Scientiae - MSc / Tellurium is a member of the chalcogen group in the periodic table and is known to be a better semiconductor material when compared to sulfur and selenium. By introducing tellurium into the kesterite structure there would be an improvement in the semiconducting property of the kesterite material. This research focused on incorporating tellurium into kesterite structure in order to reduce its band-gap thereby improving its light absorption and ultimately lead to a more efficient photovoltaic effect. For a typical synthesis, kesterite nanoparticles were synthesized by anion hot injection process which involved the injection of the anion precursor comprising of sulfur, selenium and tellurium in diethylene glycol into a solution containing the cation precursor which are copper (II) chloride, Zinc chloride and tin (II) chloride which are dissolved in diethylene glycol. The synthesized nanoparticles were copper zinc tin sulfide (CZTS), copper zinc tin sulfide selenide telluride (CZTSSeTe) and copper zinc tin sulfide telluride (CZTSTe). Morphological characterization of the synthesized nanoparticles was carried out by high-resolution scanning electron microscopy (HRSEM) and high-resolution transmission electron microscopy (HRTEM) to obtain the shape of the surface and internal structure of the nanoparticles respectively. The micrograph obtained from HRSEM shows that all synthesized nanoparticles had a flower-like surface appearance which is a common morphology obtained for non-vacuum synthesized kesterite nanoparticles. The micrograph obtained from TEM showed that all nanoparticles were agglomerated and had a black surface covering which attributable to the solvent used during synthesis, washing and centrifugation. The internal structure of the synthesized nanoparticles was obtained through small angle x-ray scattering (SAXS) plot of the shapes. The shape obtained for the nanoparticles were core shell hollow sphere for CZTS, core shell dumb-bell for CZTSSeTe and solid sphere for CZTSTe.

by Ka-Suen Lee. / "June 1998." / Thesis (Ph.D.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

The E and B EXperiment (EBEX) is a pointed balloon-borne telescope designed to measure the polarization of the cosmic microwave background (CMB) as well as that from Galactic dust. The instrument is equipped with a 1.5 meter aperture Gregorian-Dragone telescope, providing an 8' beam at three frequency bands centered on 150, 250 and 410 GHz. The telescope is designed to measure or place an upper limit on inflationary B-mode signals and to probe B-modes originating from gravitationnal lensing of the CMB. The higher EBEX frequencies are designed to enable the measurement and removal of polarized Galactic dust foregrounds which currently limit the measurement of inflationary B-modes. Polarimetry is achieved by rotating an achromatic half-wave plate (HWP) on a superconducting magnetic bearing. In January 2013, EBEX completed 11 days of observations in a flight over Antarctica covering 6,000 square degrees of the southern sky. This marks the first time that kilo-pixel TES bolometer arrays have made science observations on a balloon-borne platform. In this thesis we report on the construction, deployment and data analysis of EBEX. We review the development of the pointing sensors and software used for real-time attitude determination and control, including pre-flight testing and calibration. We then report on the 2013 long duration flight (LD2013) and review all the major stages of the analysis pipeline used to transform the ~1 TB of raw data into polarized sky maps. We review "LEAP", the software framework developed to support the analysis pipeline. We discuss in detail the novel program developed to reconstruct the attitude post-flight and estimate the effect of attitude errors on measured B-mode signals. We describe the bolometer time-stream cleaning procedure including removing the HWP-synchronous signal, and we detail the map making procedure. Finally we present a novel method to measure and subtract instrumental polarization, after which we show Galaxy and CMB maps.

Neste estudo foi feita uma detalhada caracterização das propriedades óticas de partículas de aerossóis biogênicos, de poluição urbana e de queimadas na bacia Amazônia. Foram utilizadas diferentes abordagens, incluindo medidas in-situ e por sensoriamento remoto em várias localidades. Radiômetros solares da rede AERONET e instrumentos de medida de absorção (Aetalômetros e MAAP) e espalhamento (Nefelômetros) foram utilizados no experimento GoAmazon2014/5 que estudou o efeito das emissões urbanas de Manaus nas propriedades de aerossóis. Em regiões impactadas pela queima de biomassa, a forçante radiativa foi quantificada através de medidas da AERONET, separando as contribuições de carbono orgânico (OC) e elementar (EC). Com base apenas nas propriedades óticas dos aerossóis, foi feita uma análise qualitativa dos tipos de aerossóis dominantes durante a queima de biomassa na Amazônia, avaliando seus impactos no balanço radiativo. O OC emitido nas queimadas tem forte efeito de resfriamento no topo da atmosfera, com uma forçante radiativa de -53 ± 17 W/m². O EC é altamente absorvedor e, apesar de estar presente em menor quantidade que o OC, apresenta um forte efeito na forçante radiativa no topo da atmosfera, tornando-a significativamente menos negativa, com efeitos de até -12 ± 9 W/m². As propriedades de absorção e espalhamento associadas com as emissões urbanas da cidade de Manaus foram analisadas. Uma significativa diferença na componente de absorção da profundidade ótica foi observada entre dois sítios localizados vento acima e vento abaixo da pluma urbana. O efeito da absorção é notável principalmente na estação chuvosa, mas também pode ser observado com as plumas de queimadas na estação seca. A partir de medidas in-situ, foi observado que o albedo de espalhamento simples (SSA) médio diminui de 0,92 ± 0,06 antes de Manaus para 0,83 ± 0,11 na região impactada pela pluma urbana durante a estação chuvosa. Medidas in-situ do coeficiente de absorção do particulado PM10 foram realizadas em paralelo com o PM2.5 durante a estação chuvosa na reserva ZF2 para análise da absorção de partículas grossas biogênicas. Em condições de dominância do particulado biogênico, a absorção em 880 nm do PM10 é cerca de 10% superior à absorção do PM2.5 no mesmo comprimento de onda, inferindo a absorção da radiação por partículas biogênicas na moda grossa. / In this study, a detailed characterization of aerosol optical properties for the biological, urban pollution and biomass burning aerosols was performed in the Amazon basin. A number of different approaches were used, including in-situ and remote sensing measurements in several locations. As part of the GoAmazon2014/5 experiment, solar radiometers from AERONET Network and in-situ instruments measuring absorption (Aethalometers and MAAP) and scattering coefficients (Nephelometers) were used to assess the effect of Manaus urban emissions on the aerosol properties. In regions heavily affected by the biomass burning events, the radiative forcing retrieved by AERONET was quantified, separating the contributions of organic carbon (OC) and elemental (EC). Based exclusively on the aerosol optical properties, a qualitative analysis of the dominant aerosol types was performed in the Amazon, assessing its impact on the radiative balance. The OC emitted from biomass burn has strong cooling effect at the top of the atmosphere, presenting an instantaneous radiative forcing of -53 ± 17 W/m². The EC is highly absorbing and, despite its lower concentration compared to the OC, showed a strong effect on the instantaneous radiative forcing at the top of the atmosphere, making it significantly less negative, with an effect up to -12 ± 9 W/m². The absorption and scattering properties associated with the urban emissions from the Manaus city were analyzed. A significant difference on the absorption optical depth was observed between two sites located upwind and downwind of the urban plume, respectively. The effect of absorption is particularly remarkable in the rainy season, but can also be observed with the biomass burning plumes during the dry season. In-situ measurements showed that the averaged single scattering albedo (SSA) decreased from 0.92 ± 0.06 upwind to 0.83 ± 0.11 downwind of Manaus urban plume during the wet season. In-situ measurements of the spectral absorption coefficient of PM10 cut size were performed in parallel with the PM2.5 during the wet season at ZF2 reserve in order to study the light absorption by biological coarse particles. In atmospheric conditions with the dominance of biological particles, the PM10 absorption at 880 nm is up to 10 % higher than the PM2.5 absorption at the same wavelength, inferring the absorption of radiation by coarse mode biological particles.

All animals harbor microorganisms that interact with each other and with their hosts. These microorganisms play important roles in health, disease, and defense against pathogens. The microbial communities in the intestine are particularly important in preventing colonization by pathogens; however, this defense mechanism and the means by which pathogens overcome it remain largely unknown. Moreover, while the composition of animal-associated microbial communities has been studied in great depth, the spatial and temporal dynamics of these communities has only recently begun to be explored. Here, we use a transparent model organism, larval zebrafish, to study how a human pathogen, Vibrio cholerae, invades intestinal communities. We pay particular attention to a bacterial competition mechanism, the type VI secrection system (T6SS), in this process. In vivo 3D fluorescence imaging and differential contrast imaging of transparent host tissue allow us to establish that V. cholerae can use the T6SS to modulate the intestinal mechanics of its host to displace established bacterial communities, and we demonstrate that one part of the T6SS apparatus, the actin crosslinking domain, is responsible for this function. Next, we develop an automated high-throughput light sheet fluorescence microscope to allow rapid imaging of bacterial communities and host cells in live larval zebrafish. Light sheet fluorescence microscopy (LSFM) has been limited in the past by low throughput and tedious sample preparation, and our new microscope features an integrated fluidic circuit and automated positioning and imaging to address these issues and allow faster collection of larger datasets, which will considerably expand the use of LSFM in the life sciences. This microscope could also be used for future experiments related to bacterial communities and the immune system. The overarching theme of the work in this dissertation is the use and development of advanced imaging techniques to make new biological discoveries, and the conclusions of this work point the way toward understanding pathogenic invasion, maximizing the use of LSFM in the life sciences, and gaining a better grasp of host-associated bacterial community dynamics. This dissertation includes previously published and unpublished co-authored material.

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Gravitational lensing of photons in the Cosmic Microwave Background (CMB) can be described by an integrated potential along the line of sight, the CMB lensing potential. Covariances in maps of the CMB are generated by the lensing effect, and are used to reconstruct the lensing potential itself, which is a useful probe of the matter distribution. The CMB lensing potential has been measured to high significance with CMB temperature data. However, signal to noise for lensing reconstruction from CMB polarization data is expected to be much better due to the presence of the lensing B-mode. Upcoming data from ground based CMB polarization instruments will provide high resolution maps over small patches of the sky. This will provide much better lensing reconstruction, but also presents data analysis challenges. This thesis begins with an introduction to the field of CMB lensing and CMB lensing reconstruction. The second chapter details the biases present in reconstructing the lensing potential from CMB polarization maps considering first the full sky, and then small patches of sky. It also shows that using the pure-B mode formalism for the CMB polarization leads to improved lensing reconstruction over the naive case on the cut sky. Given the upcoming improvement in the CMB lensing reconstruction, it is expected that cross-correlations of the CMB lensing with other structure tracers, such as galaxies, will yield improved information for cosmology. It is also expected that the CMB lensing will become useful to help constrain uncertainties in the galaxy power spectrum, and provide information on the linear galaxy bias and redshift distribution. The third chapter of the thesis forecasts the power of cross correlation science for a number of galactic and non-galactic parameters. Finally, the CMB lensing effects the level of non-Gaussianity observed in the CMB. The fourth chapter of the thesis is a study of the lensing effect on the primordial squeezed bispectrum. We conclude in the fifth chapter.