Inland waters including streams, rivers, reservoirs and lakes are regarded as a significant site of Organic Carbon (OC) cycling, and greenhouse gas production. As a result, there has been significant recent interest in the rates and fate of fluvial carbon exported from organic soils, such as peatlands. Additionally, peatlands can be subject to substantial degradation resulting in high rates of fluvial OC export, and this has led to efforts to repair degraded peatlands through restoration programmes. As a consequence, the study of degraded areas is useful to quantify the upper values of carbon release, understand processes of transformation, and evaluate the success of restoration programmes. Importantly peatlands are also collection areas for drinking water, which has implications for treatment, and requires better understanding of carbon cycling upstream of treatment works, in headwater rivers, reservoirs and pipes. UK upland blanket peat catchments are a key location in which to consider global questions surrounding fluvial carbon export and transformations, as they are highly degraded, provide a source of drinking water supply, and are currently undergoing pioneering methods of landscape scale restoration. This thesis considers Kinder Scout, an area of highly degraded and gullied blanket peatland in the South Pennines, UK. Using analysis of water samples collected over several years in the Kinder reservoir catchment and plateau, this thesis presents three novel contributions to global questions concerning OC cycling and peatlands. Firstly it provides (to date), the only carbon budget for a reservoir in a peat dominated catchment with high Particulate Organic Carbon (POC) export, which demonstrates that reservoirs may be net sources of Dissolved Organic Carbon (DOC), with the implication that POC-DOC interactions are important OC transformation mechanism in degraded systems. Secondly through use of a unique integrated combination of methods, it considers changes in carbon flux and composition in both river, lake and pipe locations, providing detailed understanding of the relative roles of river reaches, reservoirs and supply pipes, in controlling fluvial carbon cycling in peatland systems, and upstream of water treatment works. An important implication here, is that rate and direction of change in water treatability varies through a catchment. Finally, it includes results from the first widespread monitoring of the catchment scale effects of a new method of peatland revegetation. This restoration approach is being applied at landscape scale and the findings here, are that despite fears to the contrary, it does not lead to short term increases in fluvial carbon loss, which is an important piece of evidence supporting practical conservation approaches in these systems. To further enhance this research, a combination of field and laboratory investigations into carbon transformation processes, and ongoing restoration mentoring should be undertaken.

Philosophiae Doctor - PhD / This research charts the political and visual economies of asọ ebì in urban Lagos from 1960 to 2010. Under political economy I address the politics of asọ ebì dress in Lagos: the contestations surrounding the use of asọ ebì among friends, family members, organizations, among others. Under visual economy I engage the role of photography and other visual cultural practices in the practice of asọ ebì. From the 1960s asọ ebì began to be redefined in line with the cultural and socio-economic changes that came with late global capitalism. Within asọ ebì practice in the city of Lagos meanings of friendship, solidarity, camaraderie and wealth have undergone radical transformation as more people migrate to the city after Nigeria’s independence. From the 1970s through the 1980s, individuals were compelled by the economic conditions to adopt new modes of asọ ebì practice. For example new types of textile materials used for asọ ebì expanded to include cheaper textiles imported from China and elsewhere. Instead of offering aso ebi free, individuals sold it to their friends and within such transactions, politics of exclusion and inclusion ensued. From the 1990s through the 2000s, the rise of digital photography and the emergence of radical printing technology ushered a new mode of fashioning asọ ebì. In the process, photography and fashion magazines became a means of negotiating sartorial elegance and cosmopolitan modernity. In this thesis, therefore, the central argument resides in the contestations surrounding the use and meanings of asọ ebì within these transformations in the city of Lagos.

This dissertation adopts a quantitative approach to investigate the determinants of residents’ perceptions of neighbourhood crime, focusing specifically on a series of structural factors at the community level, in accordance with the social disorganisation model. Using different statistical models, including correlations, linear regression, multilevel models and spatial regression analyses, and several Spanish data sources, in particular the 2001 Population and Housing Census and a nationally representative survey conducted in 2006, the research confirms the relevance of its exogenous sources in explaining perceived neighbourhood crime. These include classical variables, such as neighbourhoods’ socioeconomic status, residential stability, ethnic diversity, family disruption and degree of urbanisation, but also other features related to the time, skills and resources deployed by residents in their residential areas such as commuting time to work, the number of working hours and the availability of a second home. For its part, other local conditions traditionally associated specifically with perceived neighbourhood crime, such as social incivilities and physical decay, act as mediators of other contextual effects, in particular of the number of retail shops and offices. The research also demonstrates the urban nature of the social disorganisation theory. That is, that the local conditions typically associated with social disorganisation, urban unease and the various social problems that can affect neighbourhoods, are better predictors of residents’ perceptions of crime in town and large cities than in rural areas, operationalized as municipalities of less than 5,000 inhabitants. Small municipalities seem particularly successful in controlling their younger residents for neither the proportion of adolescents and young adults, nor the number of children per family exert an important effect on residents’ perceptions of neighbourhood crime. Among these local conditions, special attention has been devoted to measures of diversity and immigration demonstrating that their effect on residents’ perceptions of neighbourhood crime, except for the positive impact of Asians, is not necessarily robust to different model specifications and statistical methods. This erratic immigrant effect is surprising given how consistent the belief in a crime-immigration nexus is among Spaniards. Precisely on this point, the dissertation has investigated why the belief in a crime-immigration nexus varies significantly between individuals and across communities. Three variables have been identified as determining factors: contextual parochialism, right-wing ideology and the media. In rural areas with high residential stability, a significant presence of elderly population and a low socioeconomic status, residents are more likely to unconsciously associate immigration and crime, even when individual attributes are adjusted for and, more importantly, even if few migrants live in the surroundings. Not surprisingly, right-wing residents are more likely to associate both phenomena yet, in contrast to many statements by scholars and pundits, the media in Spain seems to exert a moderator effect.

At low temperatures, strongly correlated materials, which typically contain partially filled d- or f-electron shells, often exhibit phases with interesting properties, which may be of both research value and technological significance. The mechanisms of phase formation in them if could be clarified, are believed to be able to provide important insights not only into physics but also into the design of new materials. In this thesis, the experimental study of two strongly correlated materials, Sr₂RuO₄ and CeAuSb₂ is presented. Sr₂RuO₄ is an unconventional superconductor, and a strong candidate for spin-triplet superconductivity. Its potential significance in relation to quantum computing also makes it of great scientific interest. In order to clarify the role of the Van Hove singularity (VHS) in its superconductivity, experimental study has been performed with the recently developed uniaxial strain methods. The experimental results suggest that as the sample is compressed towards the VHS, the transition temperature can be enhanced by a factor of =2.3 whilst the upper critical field can be enhanced by a factor of more than ten. The experimental findings are intriguing and new possibilities are open for future study. CeAuSb₂ is a Kondo lattice system which has been speculated to be close to a quantum critical point. The similarity between some of its low temperature properties and those of a well-known quantum critical system Sr₃Ru₂O₇ makes it especially interesting. In this thesis, new magnetoresistivity and torque magnetometry measurements are used to clarify its low temperature phase diagram, and reveal the strength of its magnetic anisotropy.

This thesis introduces normal factor graphs under a new semantics, namely, the exterior function semantics. Initially, this work was motivated by two distinct lines of research. One line is ``holographic algorithms,'' a powerful approach introduced by Valiant for solving various counting problems in computer science; the other is ``normal graphs,'' an elegant framework proposed by Forney for representing codes defined on graphs. The nonrestrictive normality constraint enables the notion of holographic transformations for normal factor graphs. We establish a theorem, called the generalized Holant theorem, which relates a normal factor graph to its holographic transformation. We show that the generalized Holant theorem on one hand underlies the principle of holographic algorithms, and on the other reduces to a general duality theorem for normal factor graphs, a special case of which was first proved by Forney. As an application beyond Forney's duality, we show that the normal factor graphs duality facilitates the approximation of the partition function for the two-dimensional nearest-neighbor Potts model. In the course of our development, we formalize a new semantics for normal factor graphs, which highlights various linear algebraic properties that enables the use of normal factor graphs as a linear algebraic tool. Indeed, we demonstrate the ability of normal factor graphs to encode several concepts from linear algebra and present normal factor graphs as a generalization of ``trace diagrams.'' We illustrate, with examples, the workings of this framework and how several identities from linear algebra may be obtained using a simple graphical manipulation procedure called ``vertex merging/splitting.'' We also discuss translation association schemes with the aid of normal factor graphs, which we believe provides a simple approach to understanding the subject. Further, under the new semantics, normal factor graphs provide a probabilistic model that unifies several graphical models such as factor graphs, convolutional factor graphs, and cumulative distribution networks.

The attached diploma thesis explains the transformations of companies. It shows the development of transformations in the Czech Republic and also explains the different types of transformations with emphasis on divisions. In the theoretical part it also states most common reasons for transformaitons. The practical part takes the reader through a division of the company XY. It shows all the steps that are required not only by law but also for practical reasons. The division is evaluated.

This thesis deals with the linkages between data models from conceptual models to physical design of information bases, used for implementation. The aim is to analyze the modern approach to design systems and specify how detailed the conceptual modeling and impact on the quality of the final form of application or system, including processes that take place in advance to the next level of design. Approximated the techniques the transition between these levels and will take into account structural features and limitations of selected platforms and requirements for their design and mutual coherence level view of the system. For the purpose of the thesis the well known data modeling methods are being analyzed together with their applicabilities.

The complexity of the processes whereby organic species are degraded in the atmosphere prevents many of the individual species (intermediates or products) from being unambiguously identified. Laboratory work necessarily focuses therefore on studies of idealised proxies with the aim of increasing general understanding of the physical and chemical processes which occur on particles and the types of species which they produce. Studies of the ubiquitous proxy oleic acid have resulted in the development of complex reaction schemes describing the various products and intermediates. These schemes include a diverse range of reactions and rates, thus highlighting the complications associated even with a relatively simple system. This thesis describes novel experimental studies designed to increase understanding of heterogeneous ozonolysis reactions of organic species in the aerosol phase using infrared spectroscopy as the principal analytical method. Reactions have been studied in solution (supported by off-line mass spectrometry), in thin films and in aerosols. The sensitivity of the infrared technique has also enabled the kinetics of reactions in thin films and aerosols to be followed. These methods were applied to both single- and mixed-component systems. Product studies successfully identified a number of primary and secondary species in the ozonised systems, with the secondary products formed from association reactions of the Criegee Intermediates with other species present (including self-reaction). In the mixed organic system these products were found to have originated from both a single reactant and from cross reactions between moieties from two different reactants. At low relative humidity, the ozonolysis reaction rates were monitored through the loss of the reactant species by infrared spectroscopy in the thin film and aerosol phase to give reactive uptake coefficients (gamma). At high relative humidity, the formation of products was followed. For the single-component thin films, the values obtained were gamma = 7.8 x 10-5 for stilbene and gamma = 2.0 x 10-7 for anthracene. In thin mixed films of oleic acid and stilbene, segregation occurred which prevented the effect of mixing upon the rate to be measured. A reactive uptake of gamma = 6.8 x 10-5 was obtained, identical to that of pure oleic acid. In the particle phase, the functional form of the reaction kinetics was found to be dependent on the type of particle. Pure stilbene and mixed oleic/stilbene aerosols were highly reactive and it proved necessary to treat reactive uptake coefficients under both diffusion-limited and surface-only reaction scenarios. For stilbene, the values obtained were gamma = 1.5 x 10-3 and gamma = 5.3 x 10-3 respectively. Spectral limitations in the mixed system meant that only the reaction of stilbene could be followed, giving gamma = 4.4 x 10-3 and gamma = 10.0 x 10-3 respectively. The enhanced rate in the mixture was attributed to secondary reactions. Anthracene and oleic acid coated particles were treated using a Langmuir-Hinshelwood mechanism from which the parameters KO3 (ozone partitioning coefficient) and kImax (maximum pseudo-first-order rate coefficient) could be extracted. For anthracene ozonolysis KO3 = 1.4 x 10-16 cm3 molecule-1 and kImax = 3.5x10-2 s-1. For oleic acid coated onto ammonium sulfate aerosols, values obtained were KO3 = 2.35 x 10-15 cm3 molecule-1 and kImax = 0.56 s-1 at low RH% and KO3 = 1.71 x 10-16 cm3 molecule-1 and kImax =0.33 s-1 at high RH%. The reduction in reactivity with increased RH% is principally attributed to the effect of surface polarity on ozone absorption.

Les informations visuelles sont prépondérantes pour guider le comportement. Malgré une bonne connaissance du système visuel, un phénomène représentant une latéralisation de celui-ci, le phénomène de dominance oculaire (DO), reste mal compris et finalement peu étudié. Nos travaux de thèse ont permis de démontrer que cette DO exerce une large influence sur différentes étapes de la transformation des informations visuelles en mouvements manuels ou oculaires et que celle-ci s’exprime en interaction avec d’autres latéralisations du système nerveux telles que les latéralisations manuelle et des réseaux attentionnels. Nous montrons également son influence sur les processus de transfert d'information entre les deux hémisphères du cerveau. Enfin, nos travaux comportent des retombées cliniques directes : ils introduisent une méthode de quantification plus précise de la DO utilisable par les cliniciens pour une meilleure réussite de certaines techniques chirurgicales. En conclusion, nous montrons que la DO constitue un aspect important de la latéralisation du cerveau humain, relativement négligé jusqu’à présent. / Processing of visual information from the environment is preponderant for the successful performance of many motor behaviors. Despite a good knowledge of the visual system, a phenomenon corresponding to a lateralization of this system, called eye dominance (ED), remains not well understood and poorly studied. Our thesis demonstrated that ED has a widespread influence on different levels of the transformation of visual information into manual or ocular movements and interacts with other lateralizations of the central nervous system such as the manual and attentional networks. We also show the influence of ED on the process of information transfer between the two hemispheres of the brain. Finally, our work has direct clinical implications: it introduces a more accurate method of quantifying ED which is usable by clinicians for better success of some surgical techniques. In sum, we show that ED is an important aspect of the human brain lateralization which has been overlooked until now.

Orientador: Rubens Caram Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-26T12:33:37Z (GMT). No. of bitstreams: 1 Salvador_CamiloAugustoFernandes_M.pdf: 6043299 bytes, checksum: d34b83077b59f31d9349e1c6f8532b3a (MD5) Previous issue date: 2015 / Resumo: Ligas biomédicas do sistema Ti-Nb-Sn são bastante promissoras em função de sua excelente biocompatibilidade, baixo módulo de elasticidade e resistência à corrosão. Estas propriedades são severamente influenciadas pela precipitação das fases ? e ? durante tratamentos térmicos de envelhecimento. Estudos prévios evidenciaram uma grande divergência entre a evolução microestrutural de amostras submetidas ao envelhecimento clássico (amostras solubilizadas, resfriadas em água e envelhecidas, RC) e de amostras submetidas à isoterma direta (ID). O objetivo deste trabalho é avaliar a evolução microestrutural de três diferentes composições - Ti-30Nb, Ti-30Nb-2Sn e Ti-30Nb-4Sn (% peso) durante os tratamentos isotérmicos RC e ID. As ligas foram fundidas em forno a arco, homogeneizadas (1000°C, 12 horas), resfriadas em água e laminadas a frio até a espessura de 2.5 mm, resultando em uma redução de espessura de 78%. Foram então obtidas amostras de 10 x 10 x 2.5 mm através de corte a frio. Um tratamento de recristalização foi empregado (800°C, 30 min), seguido dos tratamentos isotérmicos RC ou ID, a 400°C, por tempos entre 10 min e 48 h. Todas as amostras foram resfriadas em água após o envelhecimento. Em seguida, as amostras foram polidas e analisadas por MEV-FEG e DRX utilizando um porta-amostras giratório. Adicionalmente, medidas de microdureza e de módulo de foram executadas. Discos de 3 mm foram preparados para serem analisados por MET. Foram empregadas as técnicas de SAD, campo claro/campo escuro e CBED. Verificou-se que a adição de 4% de Sn suprime a formação de ? isotérmico a 400°C, dando origem a uma microestrutura de baixo módulo e baixa dureza. A adição de Sn permite a formação da fase ?" no resfriamento rápido executado após 48 h de isoterma direta. Para todas as composições, independentemente do tratamento térmico, a precipitação de ? ocorreu majoritariamente nos contornos de grão. Precipitados intragranulares em formato triangular também foram observados nas ligas com 2Sn e 4Sn / Abstract: Ti-Nb-Sn biomedical alloys have been recently developed as promising biomaterials due to their excellent biocompatibility, low elastic modulus and corrosion resistance. These desirable properties are highly influenced by the precipitation of ? and ? phases during aging heat treatments. Previous studies reported a great divergence between the microstructure evolution on specimens submitted to QA (quench and aged) and DH (direct holding from beta field, step-quenched, Route 2) aging heat treatments. The aim of this project was to evaluate the microstructure evolution of three different alloys - Ti-30Nb, Ti-30Nb-2Sn and Ti-30Nb-4Sn (wt %) during QA and DH isothermal aging heat treatments. The alloys were arc melted, homogenized (1000°C, 12 hours), water quenched and then cold rolled to 2.5 mm thickness, resulting in a total reduction rate of 78%. The ingot was cut in samples of 10 x 10 x 2.5 mm. A recrystallization heat treatment (800°C for 30 min) was employed, followed by the isothermal heat treatments (QA or DH) - from 10 minutes to 48 hours - and water quenching. The samples were finally polished and analysed by FEG-SEM and also X-ray diffraction (XRD) using a spinner device. Furthermore, microhardness and elastic modulus measurements were performed. Conventional TEM sample preparation was used in order to obtain 3 mm disks suitable for BF/DF/SAD and CBED analysis. It was verified the addition of 4% Sn supresses the ? formation during DH aging heat treatments at 400°C, resulting in a low hardness and low elastic modulus microstructure. This Sn addition also allows ?" to be formed on water quenching even after 48 h of aging. For all compositions, despite of the aging heat treatment, the majority of ? precipitation was given on grain boundaries. Intragranular, triangular-shape ? precipitates were also observed in Ti-30Nb-2Sn and Ti-30Nb-4Sn alloys / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica