Noncompete agreements are elements of workers' contracts that limit the worker's job mobility in the event of a job separation. In this dissertation, I address two major questions: first, why are noncompete agreements used, especially among workers earning low wages? Second, what are the ramifications of use of noncompete agreements, both for the firms using them and for the markets in which those firms exist? In the first chapter, co-authored with Matthew Johnson, I show that low wage workers sign noncompete agreements when their wages are constrained. I use a novel sample of owners of hair salons to empirically demonstrate that, when wage constraints are more binding due to a greater minimum wage or a greater labor supply, noncompete agreements are used more frequently. I show that use in this context may not maximize the firm's joint surplus, suggesting that policy interventions may be welfare-enhancing. In the second chapter, I generalize the theory of the first chapter, allowing for intertemporal changes in labor markets. I posit the existence of noncompete agreement cycles, which may explain recent trends in use among low wage employees. In a noncompete agreement cycle, workers who separate must exit the labor market. Low labor supply decreases use of noncompete agreements, allowing labor supply to increase and leading to use of noncompete agreements once again. I examine the costs and benefits of a policy prohibiting NCAs, analyzing such a policy's sensitivity to various parameters. In the final chapter, I consider the effects of noncompete agreements on the effort exertion of workers. If a worker is able to exert effort in order to increase the value of an asset, that worker may wish to spin off a new firm to leverage its value. The worker's current employer faces a tradeoff: a noncompete agreement induces the employee to stay but decreases the employee's incentive to exert effort. I show that, when the value of a spinoff is unknown ex ante, noncompete agreements may cause large ex post efficiency losses by limiting creation of highly profitable spinoffs.

O objetivo geral deste estudo é identificar desafios e perspectivas para avaliação e melhoria da mobilidade urbana através de padrões sustentáveis de geração de viagens. A investigação se baseia na aplicação de procedimentos específicos, que têm início com o cálculo do Índice de Mobilidade Urbana Sustentável (IMUS), em seis cidades brasileiras selecionadas: Belém, Curitiba, Goiânia, Juazeiro do Norte, Uberlândia e Itajubá. Além de permitir comparações entre as cidades, a aplicação do índice em vários locais serve também para identificar as mudanças que poderiam ser implementadas em sua estrutura para torná-lo mais flexível na utilização em distintos contextos. O estudo também se concentra em estratégias de planejamento para a melhoria da mobilidade urbana sustentável, com duas abordagens. Na primeira, uma avaliação simultânea de custo, prazo e risco político é levada em conta. Na segunda abordagem, um cenário hipotético é utilizado para avaliar os impactos de padrões sustentáveis de geração de viagem sobre a mobilidade urbana. Os resultados do índice indicaram que Curitiba, Uberlândia e Goiânia tiveram um desempenho melhor do que Itajubá, Belém e Juazeiro do Norte, em relação às condições de mobilidade urbana sustentável. Estes resultados também destacaram a importância do contexto nas condições de mobilidade de cada cidade estudada. As menores cidades e as das regiões mais ricas do país, por exemplo, tiveram, em geral, um desempenho melhor do que as demais. Outro fato relevante é que apenas 53% dos 87 indicadores foram calculados em todas as seis cidades, o que sugere que podem ser necessárias mudanças nos métodos de cálculo de alguns indicadores. Por outro lado, um resultado positivo da aplicação do índice em cidades distintas foi a possibilidade de identificar os aspectos comuns que ajudaram a promover a mobilidade sustentável, bem como aqueles que atuaram como obstáculos para tal. Uma forte relação entre boas condições de mobilidade e a viabilidade de ações para melhorá-las ainda mais também foi observada nos casos estudados. Mais importante do que essas observações, no entanto, podem ser os casos de indicadores com desempenho ruim, mas com boas expectativas de melhora. Estas são áreas potenciais para ações destinadas à promoção da mobilidade urbana sustentável. / The overall aim of this study is to identify challenges and perspectives for the assessment and improvement of the urban mobility through sustainable trips generation patterns. The investigation is based on the application of specific procedures, which start with the calculation of the Index of Sustainable Urban Mobility (I_SUM) in six selected Brazilian cities: Belém, Curitiba, Goiânia, Juazeiro do Norte, Uberlândia, and Itajubá. The application of I_SUM in several cities allows for comparisons between the cities. In addition, it also serves to identify changes that could be implemented in the index structure to make it more flexible for use in distinct contexts. The study also focuses on planning strategies for the improvement of sustainable urban mobility, with two approaches. In the first one, a simultaneous assessment of cost, time and political risk is taken into account. In the second approach, a hypothetical scenario is used to assess the impacts of sustainable trip generation patterns on urban mobility. The index results indicated that, re garding the sustainable urban mobility conditions, Curitiba, Uberlândia and Goiânia had a better performance than Itajubá, Belém and Juazeiro do Norte. These results also highlighted the importance of the context in the mobility conditions of each studied city. The smallest cities and those in the wealthier part of the country, for example, had in general a better performance than the others. Also relevant is the fact that only 53% of the 87 indicators have been calculated in all six cities, what suggests that changes in the calculation methods of some indicators may be needed. On the other hand, a positive outcome of the index application in distinct cities was the possibility of detecting the common aspects that helped to foster sustainable mobility, as well as those that acted as obstacles. A strong relationship between good mobility conditions and the feasibility of actions to further improve these conditions was also observed in the studied cases. More important than those observations, however, may be the cases with bad performance but high expectations of improvement. These are potential areas for actions meant to foster sustainable urban mobility.

L’Islote est une petite île artificielle de la région des Caraïbes de Colombie. Elle a commencé à être peuplée à la fin du XIX avec l’arrivée de pêcheurs itinérants qui provenaient des côtes proches de Carthagène. Pour s’y installer, ils ont comblé le sol d’un îlot et ont construit un hameau qui s’est étendu jusqu’à devenir une île d’une surface d’un hectare. Six cents insulaires qui se disent noirs et costeños y vivent, ils se consacrent à la pêche et au tourisme. Sur la base de l’ethnographie réalisée entre 2010 et 2011, cette thèse analyse la manière dont les insulaires interagissent avec leur environnement, y compris les îles, la mer et le littoral. L’Islote est un terrain totalement construit : il n’y a pas d’étendues de cultures, ni des plages, ni des palmiers. D’après les villageois il s’apparente à un “quartier” au milieu de la mer. Pour habiter cet endroit, les insulaires nouent des relations avec les autres îles et le littoral. Ils se déplacent constamment vers des villages et des villes où ils construisent des maisons dans lesquelles ils résident par périodes. De plus, ils ont noué une étroite relation avec d’autres villages de la côte, qui leur ont permis d’avoir accès à des biens, des services et aux échanges. Contrairement à d’autres lieux de la région des Caraïbes, où les relations se développent par le biais de la diversification de parentèles à plusieurs endroits, et avec différentes femmes, à l’Islote les alliances entre les membres du groupe sont privilégiées. Ici, la cohésion est interprétée comme une manière de renforcer les relations internes et ainsi pouvoir vivre à différents endroits sans perdre les liens qui les unissent. Cette thèse prétend contribuer à l’étude des interrelations caribéennes, tout en montrant qu’elles présentent des dynamiques sociales et culturelles propres. / The Islote is a small artificial island off the caribbean coast of Colombia. Its settlement began at the end of the XIX century with the arrival of itinerant fishermen from the surrounding coasts of Cartagena. To establish the island, they filled the existing key with soil and built a hamlet that grew until it reached one hectare of surface. 600 islanders live on the Islote who identify themselves as black people and costeños; they devote themselves to fishing and tourism. Based on the ethnography conducted between 2010 and 2011, the present work analyzes the ways in which the islanders relate with their environment, including other islands, the sea, and the litoral. The Islote is a piece of land totally occupied without open land: it does not have cultivation areas, beaches, or palm trees. Its appearance is interpreted by locals as a “neighborhood” in the middle of the ocean. In order to inhabit this place, the islanders extend their network of relationships towards other islands and the coast. They continuously move to small towns and municipalities where they build houses where they can reside seasonally. Furthermore, they have a tight relationship with other coastal towns; which has allowed them to gain access to goods, services, and exchanges. Unlike elsewhere in the Caribbean where relationships expand through the diversification of kin in several locations, and with many women, in the Islote the alliances between group members are prioritized. The social cohesion is interpreted here as a way to reinforce the alliances within the group and therefore makes it possible to live in different places without losing the ties that bind them. / El Islote es una pequeña isla artificial del Caribe colombiano. Se comenzó a poblar a finales del siglo XIX con la llegada de pescadores itinerantes provenientes de las costas aledañas a Cartagena. Para asentarse, ellos rellenaron el suelo de un cayo y construyeron un caserío que creció hasta conformar una isla de una hectárea de superficie. Allí conviven seiscientos isleños que se identifican como gente negra y costeña, se dedican a la pesca y el turismo. Con base en la etnografía realizada entre el 2010 y el 2011, el presente trabajo analiza la forma en que los isleños se relacionan con su entorno, incluyendo las islas, el mar y el litoral. El Islote es un terreno construido en su totalidad: no tiene zonas de cultivo, ni playas, ni palmeras. Su apariencia se interpreta desde la perspectiva de los lugareños, como de un “barrio” en medio del mar. Para habitar este lugar, los isleños amplían su red de relaciones hacia las otras islas y el litoral. Estos se mueven continuamente hacia corregimientos y municipios donde construyen casas en las que residen por temporadas. Además, tienen estrecha relación con otros poblados de la costa, que les han permitido acceder a bienes, servicios e intercambios. A diferencia de otros lugares del Caribe, donde las relaciones se expanden mediante la diversificación de parentelas en varios lugares, y con diferentes mujeres, en el Islote se privilegian las alianzas entre los miembros del grupo. La cohesión se interpreta aquí, como una forma de reforzar las relaciones internas y así poder vivir en distintos lugares sin perder los vínculos que los atan. Esta tesis pretende aportar en el estudio de las interrelaciones caribeñas, mostrando que estas presentan dinámicas sociales y culturales propias.

O mundo globalizado e o estado-da-arte dos desenvolvimentos nos remetem a um ambiente tecnologicamente complexo. Nos dias de hoje a convergência tecnológica é indiscutivelmente realidade. O usuário tem a necessidade de movimentar-se fisicamente dentro do meio em que vive e interagir com o aplicativo ou serviço que lhe é prestado. As novas gerações de sistemas de comunicação, que não mais utilizam fios em suas conexões, prevêem a integração de vários sistemas heterogêneos já existentes, unidos em uma infraestrutura capaz de, transparentemente, entregar a usuários móveis uma ampla gama de serviços com a finalidade de permitir sua comunicabilidade e acesso à informação. Com base nessas premissas, este trabalho apresenta um método para descrever um modelo de negócio para um usuário em movimento dentro de um ambiente convergente heterogêneo. O trânsito do usuário dentro das várias tecnologias de acesso para que esteja conectado a um determinado serviço é mostrado através de um framework de mobilidade e interatividade e, fundamentado nesse framework, é construído um modelo de negócio para a consecução da entrega desse serviço ao usuário. Este trabalho conceitua um modelo para um framework de mobilidade e interatividade aplicáveis a sistemas abertos; e um modelo de negócio voltado aos serviços num cenário com soluções tecnológicas interoperáveis. / The global world today and the state of the art of the technology send us to a very complex environment. Nowadays, the technological convergence a reality, where the users have the necessity of moving and where they need to interact with services and applications while moving on a wireless base. The new generations of wireless networks can integrate some existing heterogeneous systems providing a new infrastructure capable of delivering several services to moving users with transparency, allowing the communicability and the access to the users’ information. This work presents a method for the description of a generic business model for a moving user inside of a convergent heterogeneous environment. The user’s movement in this environment is modelled on a mobility and interactivity framework, where there has been built a business model to deliver services to the moving user. This thesis also presents the basic concepts of a business model for mobility and interactivity applicable to open systems.

Social mobility has been extensively documented based on two-generational associations. Whereas a few studies suggest that the approach related to social inequalities should be open to multigenerational associations, the topic of social mobility over multiple generations is still at its blooming stage. Very little is known about multigenerational effects on education in Britain and about empirical evidence of the mechanisms that underlie multigenerational effects. Drawing on the British Household Panel Survey and the UK Longitudinal Household Study, this thesis examines social mobility over three generations in Britain. The central aims of the thesis are to explore direct grandparental effects on grandchildren's educational and class attainments independent of parental influences. In particular, it focuses on mechanisms through which grandparental effects operate. The thesis finds that grandparental class is significantly associated with grandchildren's educational achievement, despite parental class, parental education, and parental wealth being taken into account. Regarding the mechanisms, the evidence suggests first that the impacts of grandparental class on education remain even though grandparents have passed away at the time of the survey, and second that the impacts disappear only when grandparents have only infrequent contact with the family. Furthermore, I find that grandparental effects are significantly stronger on grandchildren originating from advantaged parents than on those from disadvantaged parents, indicating the strong persistence of inequalities at the top of social stratification. The research also highlights significant, albeit modest, effects of grandparental class on grandchildren's class attainment over and above parental influences. For grandsons, maternal grandparental class still matters even after grandsons' education has been controlled for. In particular, self-employed grandparents have a strong impact on grandsons' likelihood of engagement in self-employment, a pattern that holds true even when parents are not self-employed. For granddaughters, neither paternal nor maternal grandparental class is found to have a direct substantial impact on granddaughters' class after granddaughters' education has been controlled for. The thesis suggests that the conventional social mobility approach based on parentchild associations may overestimate the effects of parental characteristics and underestimate the effects of family origins. Family advantages run deep; they are maintained over generations in Britain.

Glycans and their conjugates form the largest and most diverse class of biological molecules found within nature. These glycosides are vital for numerous cellular functions including recognition events, protein stabilisation and energy storage, to name a few. Additionally, abnormalities within these structures are associated with a wide range of disease states. As a result, robust analytical techniques capable of in depth characterisation of carbohydrates and their binding partners are required. Currently, liquid chromatography coupled with tandem mass spectrometry (MS2) is the 'gold standard' for characterising these species. However there are inherent challenges for 'sequencing' carbohydrates given that most structures are diastereomeric. As a result MS alone is insufficient to fully elucidate all stereochemical and often regiochemical information and alternative analytical techniques have inherent issues meaning that they are not suitable for medium/high throughput analysis. To facilitate elucidation of these structures, ion mobility spectrometry (IMS) has been used in-line with MS2. IMS of mono- and di-saccharide product ions generate by collision-induced dissociation (CID) of various glycans and their conjugates enables unambiguous identification of the monomer and the regio-/stereo-chemistry of the glycosidic bond, independent of the precursor structure. Also, given the prominence of glycans in biological recognition events, high-throughput techniques capable of elucidating and characterising carbohydrate to glycan-binding protein (GBP) interactions are highly sought after. Historically, (micro)array strategies are employed to screen large numbers of biological interactions, with detection conventionally achieved with fluorescent tagging. The major disadvantage of this approach is the requirement of a labelling step to facilitate detection of glycan-GBP binding. MS offers the ability to unambiguously identify GBPs when combined with routine bottom-up proteomics strategies, namely on-chip proteolysis followed by mass fingerprinting and MS2 analysis and subsequent comparison to protein databases. It is anticipated that these methodologies developed throughout these studies, both for carbohydrate sequencing and the characterisation of glycan-binding proteins, will greatly add to the Glycomics toolbox.

Research into the relationship between the structure and function of proteins has been ongoing now for several decades. More recently, there has been an explosion in the investigation of the dynamic properties of proteins, and how their dynamic propensity relates to their function. This new direction in protein research requires new techniques to analyse protein dynamics, since most traditional techniques are biased towards a fixed tertiary structure. Mass spectrometry (MS) is emerging as a powerful tool to probe protein dynamics since it can provide information on interconverting conformations and has no preference towards the folded state. Furthermore, its low sample consumption, rapid data acquisition and low data processing positions MS as an attractive tool in protein structure research. The hybrid technique of ion mobility-mass spectrometry provides further insight into the range of conformations adopted by proteins and protein complexes, by providing information on the size in terms of rotationally averaged collision cross section. The work presented in this thesis considers proteins with a range of structural characteristics. We use ion mobility mass spectrometry to investigate proteins of different extents of disorder, protein complexes with dynamic entities and a system that undergoes structural rearrangement upon ligand binding. First, a framework of mass spectrometry experiments is described which allows identification of the extent of structure and disorder within proteins. This framework is tested on a range of different systems throughout the thesis. Differences in the gas-phase properties of two conformationally dynamic proteins which behave similarly in solution are investigated and from this research we postulate a new ionisation mechanism for partially folded proteins. The dynamic propensity of C-terminal p27 is investigated and compared to two permutants which allows us to delineate how the location of charged residues in a primary sequence affects the structure of a protein. We monitor the 'folding-upon-binding' behaviour of p27 upon association with its binding partners, and how this differs with the order of charged residues in the linear sequence. Finally, we describe the structural rearrangement of Fdc1 upon the binding of its cofactor; a prenylated FMN molecule. This thesis demonstrates the suitability of ion mobility-mass spectrometry for the investigation of dynamic properties of proteins and protein complexes.

This thesis explores how Chilean teachers understand their life trajectories in terms of life-course change, socio-historical change and social mobility, examining whether they make distinctions between these different kinds of understandings of transitions. In a context of 40 years of transformations in Chile, teachers are used as a case-study for examination of the subjective dimension of social mobility, and people's sense of class location and inequality. Methodologically, this research adopted the approach of exploring people's sense of life course and social movement in its broadest sense, examining how teachers talked about their life trajectories in order to consider whether questions of social change, life-course change, social structure and social mobility featured. It is built on data collected through interviews with 41 teachers who live in Santiago, who were asked to outline their personal timelines as a way to reflect on the main changes which they regarded as significant in their life stories. The argument of this thesis draws on and contributes to sociological work on class and social mobility. Most social mobility research has been dominated by quantitative work about occupational patterns of movement, with subjective social mobility neglected because people's subjective understandings of social movement have been seen to be contradictory and inconsistent. It has been suggested that 'lay' understandings fail to distinguish 'social mobility' from socio-historical change and life-course change, so people fail to recognise the true extent of inequality and the limited nature of social mobility. This thesis foregrounds subjective social mobility and critically examines these assumptions. On the basis of my empirical research, I argue that the apparent inconsistences in 'lay' subjective social mobility disappear, or at least make more sense, when we locate people's understandings of social location, social change and social mobility within their broader sense of their life stories. These inconsistencies are partly the result of the complex ways in which people understand their life stories and position themselves within a broader social structure, and are best explained using an analytical focus which emphasises the multidimensional nature of trajectories in social space (Bourdieu, 1984) and a methodological focus which is sensitive to the multifaceted and practical ways in which people speak about their lives. The teachers in my sample resisted a linear summary of their timelines and issues of life-course change and socio-historical change also framed their accounts, adding additional layers of complexity to them, in narratives of trajectories along different dimensions which qualified or disrupted each other. Despite that the teachers framed their trajectories as complex, non-linear constructs, and some rejected 'social mobility' stories, they still all offered overall evaluations of their changing life circumstances. They looked beyond their own trajectories to make different sort of comparisons which helped them to establish a sense of relative social movement, characterising their lives as showing social improvement, stability or decline as different views of their relative social position, and of the social structure and inequalities. I argue that rather than focusing on whether or not ordinary people correctly recognise relative or absolute mobility, it is more pivotal to examine how these different understandings come into play when ordinary people reflect about their location in an unequal society. The thesis argues that subjective social mobility needs to be analysed in term of a multidimensional model of class location and class movement, and this also argues for a greater understanding of the complexities of issues of social location, trajectories and social mobility in which 'class' emerges in different way in people's accounts. Therefore, a more open-ended approach to how people understand their relative situation is needed, in order to explore whether and how issues of class position, social inequalities and social mobility feature in the accounts of 'ordinary' people when they discuss the key transitions of their lives.

Triacetone triperoxide has been synthesised for a range of experimental studies towards the reactivity, stability and gas phase metal complexation of the explosive. Reaction with transition metals was performed and a series of molten TATP experiments conducted at 120 °C. The effect of a molten state on the degradation, conformation and reactivity of TATP has been studied with the formation of diacetone diperoxide, acetone and acetic acid degradation products observed. The complexation of TATP with a range of metals has been studied by electrospray ionisation-mass spectrometry, yielding [M+Cat]+ ions for all of the alkali metals. The first observations of a [TATP+Ag]+ adduct have been made. The formation of [2TATP+Li+LiX]+ (X = Br, Cl) and [2TATP+Ag]+ sandwich complexes was also observed. Collision cross sections (CCS) for the lithium-containing complexes of TATP were measured by travelling wave ion mobility-mass spectrometry, comparing well to computationally determined structures.

Orientador: Carlos Roberto Grandini / Banca: Alfredo Gonçalves Cunha / Banca: Paulo Noronha Lisboa Filho / O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp / Resumo: Desde a descoberta dos supercondutores com alta Tc, vários trabalhos têm sido efetuados sobre as diferentes propriedades destes materiais. As cerâmicas Y'BA IND.2' "C IND.U 'IND.3' 'O IND. 7-'delta' mostraram que tem suas propriedades supercondutoras fortemente afetadas pela quantidade de oxigênio. Mais recentemente, medidas de relaxações anelásticas em 'LA IND.2'CU 'O IND. 4+'delta' mostraram que a remoção deste elemento pode ser relacionada com dois eventos. Um deles é o decréscimo na mobilidade entre dois planos adjacentes CuO e o outro, é o aumento no número de padrões de mobilidade para os octaedros CU 'O IND. 6'. Para SM'BA IND.2' "C IND.U 'IND.3' 'O IND. 7-'delta' (SBCO), a possibilidade de uma estequiometria de oxigênio variável e sua alta mobilidade nos planos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Since the discovery of the high Tc superconductors, several works have been made about the different propoerties of these materials. Y'BA IND.2' "C IND.U 'IND.3' 'O IND. 7-'delta' ceramic showed to have its superconducting properties strongly affected by the oxygen content. More recently, anelastic relaxation measurements in 'LA IND.2'CU 'O IND. 4+'delta', showed that the remotion of this element can be related to two events. One is the decrease in mobility between two adjacent CuO planes, and the other is the increase in the number of tilting patterns of the Cu 'O IND. 6' octahedra. For SM'BA IND.2' "C IND.U 'IND.3' 'O IND. 7-'delta' (SBCO), the possibility of variable stoichiometry and the high mobility of oxygen in the... (Complete abstract, click electronic access below) / Mestre