Este trabalho avaliou a bioacumulação de metais e as respostas biológicas em mexilhões Perna perna coletados na Praia da Cocanha, Ilha das Palmas e Ponta de Itaipu, e ostras Crassostrea brasiliana coletadas nos Estuários de Cananéia, Santos e Bertioga em diferentes estações do ano. Foram realizadas duas campanhas: 2008/09 e 2016/17. A Cocanha apresentou elevados níveis de metais, indução de EROD e DBF e efeitos peroxidativos e genotóxicos. Em Palmas houve ativação de EROD, DBF, GST e GSH. Itaipu evidenciou bioacumulação de metais, ativação de GST e GSH e danos no DNA. Em Cananéia houve bioacumulação de As e Cr, respostas das fases I e II e efeitos peroxidativos. Santos exibiu piores condições fisiológicas, com alterações bioquímicas em todas as estações do ano. Bertioga piorou em 2016/17 em relação a 2008/09, evidenciado por maior bioacumulação de metais e respostas de biotransformação e antioxidantes e efeitos neurotóxicos. Os dados evidenciam fontes de contaminação diferentes para cada local e variação de acordo com o período do ano em função de diversos fatores (e.g. pluviosidade, reprodução, turismo). Os locais escolhidos como referência demonstraram estar sob influência de fontes pontuais de contaminação. Deve-se considerar que Itaipu e Cananéia integram unidades de conservação. / The present study assessed the bioaccumulation of metals and the biological responses in mussels Perna perna from Cocanha Brach, Palmas Island and Ponta de Itaipu, and oysters Crassostrea brasiliana from the estuaries of Cananéia, Santos and Bertioga in different seasons. Two campaigns were carried out: 2008/09 and 2016/17. Cocanha showed high levels of metals, induction of EROD and DBF and peroxidative and genotoxic damages. Palmas exhibited induction of EROD, DBF, GST and GSH. Itaipu exhibited bioaccumulation of metals, activation of GST and GSH and DNA damage. Cananéia showed bioaccumulation of As and Cr, phases I and II responses and peroxidative damage. Santos exhibited the worst physiological conditions, with biochemical alterations in all seasons. Bertioga conditions worsened in 2016/17 compared to 2008/09, evidenced by the higher content of metals and biotransformation and antioxidant responses and neurotoxic damage. These data show different sources of contamination for each site and variation in accordance with the time of the year due to several factors (e.g. rainfall, reproduction, tourism). The sites chosen as reference may be influenced by point sources of contamination. It should be considered that Itaipu and Cananéia are within protected areas.

A pesquisa utiliza a Cena Contemporânea (2011-2013) e o jogo do Círculo Neutro como anteparos para os processos de preparação e criação do ator. Primeiro, procura refletir sobre os ambientes formativos, relacionando as proposições de Agamben sobre o \"ser qualquer [e o] assim, irreparável\" (1993), com as de Bauman sobre \"comunidade, segurança, liberdade e estrangeiro\" (2003). Segundo, busca cartografar o Círculo Neutro e, para isso, entrevista François Kahn, Francisco Medeiros, Inês Aranha e Maurício Paroni de Castro. Depois, junto a um grupo de atores, instala um campo de verificação prático e experimental para vivenciar, derivar, descrever e enquadrar o Círculo Neutro como \"jogo\". Considera que o jogo e o jogar, portadores dos aspectos risco, acidente e imprevistos, mostram-se produtivos para o trabalho do ator e para o desenvolvimento orgânico da cena, pois colaboram para a formação de um artista mais \"aberto\" e com \"jogo de cintura\". / The study uses the Contemporary Scene (2011-2013) and the Neutral Circle game as support for the actors\' processes of preparation and creation. Firstly, it aims at reflecting about the education environments by relating the propositions of Agamben about the \"whatever being [and the] therefore, irreparable\" (1993), with those of Bauman about \"community, safety, freedom and foreign\" (2003). Secondly, it tries to map the Neutral Circle, and for that interviews François Khan, Francisco Medeiros, Inês Aranha, and Maurício Paroni de Castro. Afterwards, with a group of actors, it establishes a space of practical and experimental verification to experience, derive, describe and frame the Neutral Circle as a \"game\". The analysis considers that the game and the act of playing, involving the aspects of risk, accident and the unexpected, are productive for the work of the actor and for the organic development of the scene, because they collaborate with the formation of an artist who is more \"open\" and \"more flexible\".

Este trabalho avaliou a bioacumulação de metais e as respostas biológicas em mexilhões Perna perna coletados na Praia da Cocanha, Ilha das Palmas e Ponta de Itaipu, e ostras Crassostrea brasiliana coletadas nos Estuários de Cananéia, Santos e Bertioga em diferentes estações do ano. Foram realizadas duas campanhas: 2008/09 e 2016/17. A Cocanha apresentou elevados níveis de metais, indução de EROD e DBF e efeitos peroxidativos e genotóxicos. Em Palmas houve ativação de EROD, DBF, GST e GSH. Itaipu evidenciou bioacumulação de metais, ativação de GST e GSH e danos no DNA. Em Cananéia houve bioacumulação de As e Cr, respostas das fases I e II e efeitos peroxidativos. Santos exibiu piores condições fisiológicas, com alterações bioquímicas em todas as estações do ano. Bertioga piorou em 2016/17 em relação a 2008/09, evidenciado por maior bioacumulação de metais e respostas de biotransformação e antioxidantes e efeitos neurotóxicos. Os dados evidenciam fontes de contaminação diferentes para cada local e variação de acordo com o período do ano em função de diversos fatores (e.g. pluviosidade, reprodução, turismo). Os locais escolhidos como referência demonstraram estar sob influência de fontes pontuais de contaminação. Deve-se considerar que Itaipu e Cananéia integram unidades de conservação. / The present study assessed the bioaccumulation of metals and the biological responses in mussels Perna perna from Cocanha Brach, Palmas Island and Ponta de Itaipu, and oysters Crassostrea brasiliana from the estuaries of Cananéia, Santos and Bertioga in different seasons. Two campaigns were carried out: 2008/09 and 2016/17. Cocanha showed high levels of metals, induction of EROD and DBF and peroxidative and genotoxic damages. Palmas exhibited induction of EROD, DBF, GST and GSH. Itaipu exhibited bioaccumulation of metals, activation of GST and GSH and DNA damage. Cananéia showed bioaccumulation of As and Cr, phases I and II responses and peroxidative damage. Santos exhibited the worst physiological conditions, with biochemical alterations in all seasons. Bertioga conditions worsened in 2016/17 compared to 2008/09, evidenced by the higher content of metals and biotransformation and antioxidant responses and neurotoxic damage. These data show different sources of contamination for each site and variation in accordance with the time of the year due to several factors (e.g. rainfall, reproduction, tourism). The sites chosen as reference may be influenced by point sources of contamination. It should be considered that Itaipu and Cananéia are within protected areas.

The impressive progress that elementary particle physics made in the second half of the last century led to the formulation of a comprehensive theory, known as the Standard Model (SM), which correctly describes all fundamental interactions in nature, except for the gravitational one. Indirect discoveries have always played an important role in high energy physics scenario and indirect research can be considered to all intents and purposes complementary to the direct one, since allows to test much higher energy scales than those the current colliders are able to reach. This is very important now that electroweak precision tests and measurements on Flavour Changing Neutral Currents (FCNC) processes put very stringent constraints on physics beyond the SM, requiring it to appear at scales O(10 TeV). On the other hand, New Physics (NP) is expected already at scales O(1 TeV) in order to offer a natural explanation to the smallness of the Higgs mass. This scale is also confirmed by recent constraints on thermal dark matter [1] which show how new physics should manifest not far above the electroweak scale. Rare B decays have always played a crucial role in shaping the flavour structure of the SM and particle physics in general. Since the first measurement of rare radiative B æ Kú“ decays by the CLEO Collaboration [2] this area of particle physics has received much experimental and theoretical attention. In particular, FCNC B decays, involving the b-quark transition b æ (s, d) + “ and b æ (s, d) + ¸+¸≠(¸ = e, μ, ·, ‹), provided crucial tests for the SM at the quantum level since they proceed through loop or box diagrams, and they are highly suppressed in the SM (also by helicity). Hence, these rare B decays are characterised by their high sensitivity to NP. The B0 s æ μ+μ≠ channel is the most direct example of the b æ s ¸¸ transitions. The SM predicted branching ratio [3] can be enhanced by coupling to non-SM heavy particles, such as those predicted by the Minimal Supersymmetric Standard Model (MSSM) and other extensions. Updated measurements on the B0 s æ μ+μ≠ branching ratio have been presented by ATLAS [4], LHCb [5] and CMS [6] collaborations. In this thesis I will report all the studies I performed within the rare B decays ATLAS group, measuring the branching ratio of the B0 s æ μ+μ≠ channel on data collected during LHC Run 1. The first chapter provides a general introduction to the SM, focusing in particular on the flavour sector and the possible new physics scenarios. Chapter 2 briefly introduces the LHC collider and the ATLAS detector, detailing the muon and trigger systems, fundamental for the rare B decays measurements. In chapters 3 and 4, I will summarise the work done, during my presence at CERN, on the ATLAS semiconductor strip detector, monitoring the Lorentz angle during Run 1 and measuring the backplane resistance of the silicon modules installed in the ATLAS cavern. In chapter 5, I will review the strategy adopted to measure the B0 s æ μ+μ≠ branching ratio, reporting all the studies I performed on the combinatorial background, and the results obtained on 4.9 fb≠1 of data collected in 2011. Chapters 6 and 7 detail respectively the additional studies I performed on the 2011 datasets and all the tests I made in preparation for the analysis on 20 fb≠1 of data collected in 2012. I will show the studies on the discriminating variables for the rejection of the background, the tests on the multivariate analysis and on the possible strategies for the invariant mass fit for the extraction of the signal yield. All these studies proved to be fundamental for the 2012 measurement detailed in chapter 8.

Orientadora: Telma Teresinha Berchielli / Banca: Izabelle Auxiliadora Molina de Almeida Teixeira / Banca: Paulo Henrique Moura Dian / Resumo: Os objetivos foram avaliar diferentes formas de dosagem de indicadores (infusão contínua 24h, e duas doses diária de indicador) e verificar sua precisão e acurácia para estimativa do fluxo duodenal de matéria seca (MS), consumo de concentrado, consumo de volumoso, produção fecal e digestibilidade aparente da MS em bovinos. No experimento 1, seis animais receberam os indicadores Cr-EDTA e YbCl3 através de uma bomba de infusão contínua, via fístula ruminal durante seis dias de adaptação nos dois períodos de 17 dias, enquanto os outros seis animais receberam os mesmos indicadores em duas dosagens diárias (8h e às 19h). No experimento 2, doze animais receberam os indicadores Cr-EDTA, YbCl3, LIPE®LÍQUIDO, FDNi e FDAi, em duas doses diárias que foram utilizados nas estimativas do fluxo duodenal de matéria seca (MS) pelo método de único e duplo indicador. Os indicadores TiO2 e LIPE®LÍQUIDO foram utilizados para estimativa do consumo de concentrado, produção fecal, digestibilidade aparente e os indicadores internos, FDNi e FDAi para estimar consumo de volumoso, produção fecal e digestibilidade. No experimento 1, o delineamento utilizado foi inteiramente casualisado em parcelas subdivididas com dois tratamentos em dois períodos. No experimento 2, o delineamento foi o de blocos em parcelas subdivididas. As médias foram comparadas pelo teste tukey a 5%. No experimento 1 não foram observadas diferenças entre as formas de fornecimento dos indicadores (P>0,05). No experimento 2, a FDNi estimou o fluxo de digesta no duodeno e a produção fecal e o consumo de volumoso. A estimativa do consumo de volumoso através do FDNi e FDAi foram semelhantes ao observado (P>0,05). O TiO2 e LIPE®LÍQUIDO foram acurados na estimativa do consumo de concentrado / Abstract: The objectives of this study were to evaluate by two metabolism trials different ways to dose markers (by continuous infusion for 24 hours and by two doses of marker per day) and also to study the accuracy and reliability of differents markers to estimate duodenal flow of nutrients concentrate intake, roughage intake, fecal production and apparent digestibility of dry matter (DM) in cattle. Twelve crossbred heifers were used in both experiments with average body weight of 361.7kg ± 59 and approximately 24 months of age, cannulated in the rumen and duodenum. In experiment 1, six animals received the markers Cr-EDTA, YbCl3 by continuous infusion via ruminal fistula in two periods of 17 days, while the other six animals received the same markers in twice daily dosing (8 and 7hours). In experiment 2, animals received the twelve markers twice daily during the experimental periods. Markers Cr-EDTA, YbCl3, LIPE®LIQUID, iNDF and iADF were used in the estimation of duodenal flow of nutrients by the method of single and double markers. Markers TiO2 and LIPE®LIQUID were used to estimate concentrate intake, fecal output, digestibility of DM and internal markers, iNDF and iADF to estimate forage intake, digestibility and fecal production. In experiment 1, a split plot design was used with two treatments (supply), six replicates in two periods. In experiment 2, the experimental design was randomized blocks in split plots, where the markers were considered as treatments. In both experiments, the means were compared by Tukey test at 5%. In experiments 1, there were no differences between the ways to supply the marker (P>0.05). In experiment 2, the iNDF was the best variable to predict digest flow in the duodenum and fecal production. iNDF and iADF were not d significantly different when the average intake of roughage were compared with the observed. The TiO2 was not significantly different... (Complete abstract click electronic access below) / Mestre

Os modelos de otimização de carteiras baseados na análise média-variância apresentam dificuldades para estimação das matrizes de covariância, usadas no processo de otimização, o que leva a necessidade de métodos ad hoc para limitar ou suavizar as alocações eficientes recomendadas pelo modelo. Embora as carteiras obtidas por este método sejam eficientes, não é assegurado que o tracking error seja estacionário, podendo a carteira se distanciar do benchmark, exigindo frequentes recomposições. Neste artigo é empregada a metodologia de cointegração para otimização de carteiras no âmbito de duas estratégias: index tracking e estratégia long-short. A estabilidade das carteiras otimizadas através da cointegração em diferentes cenários de mercado, diminuindo custos relativos a frequentes recomposições da carteira, e níveis de retorno e volatilidade superiores aos benchmarks, mostram que a metodologia é uma ferramenta eficiente e capaz de gerar resultados robustos, se caracterizando como uma atraente ferramenta para a gestão quantitativa de recursos. Modelar a estrutura a termo da taxa de juros é extremamente importante para macroeconomistas e participantes do mercado financeiro em geral. Neste artigo é empregada a formulação de Diebold-Li para ajustar e fazer previsões da estrutura a termo da taxa de juros brasileira. São empregados dados diários referentes às taxas dos contratos de DI Futuro negociados na BM&F que apresentaram maior liquidez para o período de Janeiro de 2006 a Fevereiro de 2009. Diferentemente da maior parte da literatura sobre curva de juros para dados brasileiros, em que o modelo de Diebold- Li é estimado pelo método de dois passos, neste trabalho o modelo é colocado no formado de estado espaço, e os parâmetros são estimados simultaneamente, de forma eficiente, pelo Filtro de Kalman. Os resultados obtidos tanto para o ajuste, mas principalmente no que diz respeito à previsão, mostram que a estimação do modelo através do Filtro de Kalman é a mais adequada, gerando melhores previsões para todas as maturidades quando é considerado horizontes de previsão de um mês, três meses e seis meses. No terceiro artigo artigo nós propomos estimar o modelo dinâmico da estrutura a termo da curva de juros de Nelson e Siegel (1987) considerando duas especificações alternativas. Na primeira, nós consideramos os pesos dos fatores como variantes no tempo e tratamos a heterocedasticidade condicional via um modelo volatilidade estocática com fatores comuns. No segundo caso, consideramos um modelo onde os fatores latentes seguem individualmente processos autoregressivos com volatilidade estocástica. Os assim chamados fatores de volatilidade buscam capturar a incerteza ao longo do tempo associada ao nível, inclinação e curvatura da curva de juros. A estimação é realizada através de métodos de inferência bayesiana, por Markov Chain Monte Carlo. Os resultados mostram que os fatores de volatilidade são altamente persistentes, dando suporte ao fato estilizado de que os choques na volatilidade das taxas de juros são altamente persistentes, e também indicam que o uso de estruturas de volatilidade estocástica levam a melhores ajustes dentro da amostra para a curva de juros observada. / The traditional models to optimize portfolios based on mean-variance analysis aim to determine the portfolio weights that minimize the variance for a certain return level. The covariance matrices used to optimize are difficult to estimate and ad hoc methods often need to be applied to limit or smooth the mean-variance efficient allocations recommended by the model. Although the method is efficient, the tracking error isn’t certainly stationary, so the portfolio can get distant from the benchmark, requiring frequent re-balancements. We used the cointegration methodology to devise two quantitative strategies: index tracking and long-short market neutral. We aim to design optimal portfolios acquiring the asset prices’ co-movements. We used Ibovespa’s index and stocks from Jan-2000 to Dec-2008. The results show that the devise of index tracking portfolios using cointegration generates goods results, replicating the benchmark’s return and volatility. The long-short strategy generated stable returns under several market circumstances, presenting low volatility. Modeling the term structure of interest rate is very important to macroeconomists and financial market practitioners in general. In this paper, we used the Diebold-Li interpretation to the Nelson Siegel model in order to fit and forecast the Brazilian yield curve. The data consisted of daily observations of the most liquid future ID yields traded in the BM&F from January 2006 to February 2009. Differently from the literature on the Brazilian yield curve, where the Diebold-Li model is estimated through the two-step method, the model herein is put in the state-space form, and the parameters are simultaneously and efficiently estimated using the Kalman filter. The results obtained for the fit and for the forecast showed that the Kalman filter is the most suitable method for the estimation of the model, generating better forecast for all maturities when we consider the forecasting horizons of one and three months. In the third essay we propose to estimate the dynamic Nelson-Siegel model of yield curve considering two alternative specifications. At first, we consider the factor loadings such as time-varying conditonal heteroskedasticity and treat via a common factors of stochastic volatility models. In the second case, we consider a model where the latent factors individually following autorregressive process with stochastic volatility. The volatility factors seek to capture the uncertainty over time associated with level, slope and curvature of yield curve.The estimation is performed through bayesian inference, Markov Chain Monte Carlo. The volatility factors showed high persistence, supporting the stylized fact that shocks in the volatility of interest rate are highly persistent, and also indicate that the used of structures of stochastic volatility lead to better in-sample fits of the observed yield curve.

Inter-ocular suppression occurs when very different images are presented to each eye. Diplopia ensues if different images are superimposed and perceived. The brain removes this unfavourable viewing experience by suppressing one eye’s input to enable clear single vision. Inter-ocular suppression during visual development occurs in response to sufficiently disparate images caused by strabismus (misalignment of the visual axis) or anisometropia (uncorrected difference in refractive error), and if persistent may result in amblyopia. This is reduced visual sensitivity, usually in one eye, to a range of visual functions that cannot be corrected by refraction. Furthermore, binocular vision is reduced or absent. Depth and extent of suppression is measured across the central visual field in healthy participants with monocularly blurred vision, healthy participants with monocularly reduced luminance using neutral density (ND) filters, and participants with naturally disrupted binocular vision and/or amblyopia. Suppression of spatial stimuli defined by luminance (L) and luminancemodulated noise (LM) was compared to that measured for stimuli defined by contrast-modulated noise (CM), for which there is no change in mean luminance. For all stimuli suppression depth increased with increased imbalance of binocular input. Suppression was of a similar depth across the visual field with imposed blur and localised central suppression was found with ND filters. Microstrabismics showed central suppression, while strabismic amblyopes showed central in addition to hemifield suppression. Suppression for all participants was measured to be deeper for CM spatial stimuli than for LM spatial stimuli. This is suggested to be a result of CM stimuli engaging more binocular mechanisms of processing, than LM stimuli, thereby becoming more sensitive to disruptions of binocularity such as those produced in the participants in the present study. CM stimuli are therefore more sensitive to detecting suppression, which is associated with amblyopia.

O autor explora o corpo neutro do referente da imagem fotográfica e o resultado da sua pesquisa é este conjunto de narrativas. Cada uma é construída a partir dos retratos da família e desenvolvida em diálogo com outros autores. Ele conta em particular a história de um homem e de uma mulher. Mas eles não são um casal. Ele é avô dela. E ela, ainda criança nestas imagens, é agora mãe do autor. Ele lê no verso do retrato dela: \"Vimeiro 1968\". É a costa ocidental portuguesa. Lugar onde se travou a batalha com os franceses no início do século XIX e, pelo que parece, destino de férias da sua família. Lugar esperado e distante, onde águas doces e salgadas se encontram e a ilha de Saturno pontua o horizonte. Ilha granítica situada no oceano Atlântico, a meia dúzia de milhas do Cabo Carvoeiro. No horizonte do Vimeiro, onde o avô ensinou a criança a nadar. Acontecimento testemunhado pelo aparelho fotográfico do pai e comprovado até hoje pelos retratos do álbum da família. Nestas férias o avô ensinou-a a nadar e o seu pai foi fotógrafo, a avó cozinhou e a mãe costurou um sorriso, não fosse ter chorado na Rocha do Conde de Óbidos quando ele embarcou no paquete Pátria da Companhia Nacional de Navegação no dia 29 de Agosto de 1961. / The author explores the referent\'s neutral body in the photographic image and the result of his research is this set of narratives, each one built from the family\'s portraits and the dialogue with other authors. He tells in particular the story of a man and a woman. They are not a couple though. He is her grandfather and she, a child in these images, is now the author\'s mother. He reads on the back of her picture, \"Vimeiro 1968\". It is the Portuguese west coast. Where the battle with the French was fought in the early nineteenth century and, it seems, his family\'s vacation destination. Expected and distant place, where fresh and salt waters meet and Saturno Island punctuates the horizon. Granitic island situated in the Atlantic Ocean, half a dozen miles from Cabo Carvoeiro. In the horizon of Vimeiro where the grandfather taught the children to swim. Event witnessed by the father\'s photographic apparatus and today testified by the pictures in the family\'s album. This holiday grandfather taught her to swim, father was photographer, grandmother cooked, and mother sewed a smile, had not she wept in Rocha do Conde de Óbidos when he boarded the packet Pátria, of Companhia Nacional de Navegação, on August 29, 1961.

This doctoral project explores the ways in which European small states' approaches to peacekeeping have been affected by the changing nature of peace missions. The central objective is to explain the choices made by small states' governments to participate in missions which no longer fit traditional peacekeeping models. The increasing need for comprehensive and robust responses to international crises characterised by intra-state violence has challenged small states whose elites and publics have been accustomed to deploying troops to low intensity missions tasked to separate parties. Throughout the Cold War and beyond, traditional peacekeeping developed along the norms of non-use of force, impartiality and consent. Identifying positively with the objectives and normative underpinnings of traditional peacekeeping, small states have actively committed their armed forces based on a perception of themselves as international norm entrepreneurs. This thesis challenges the notion that small states' governments commit material and human resources to new types of peace operations motivated by such self-images. Transformations in the practice of peacekeeping are forcing foreign policy agents in small states to rethink the function(s) that their states should play in the international system towards peacekeeping. Three questions are considered: I) what new or existing roles are small states adopting in this evolving peacekeeping system? II) through what political processes do these roles emerge? and III) how do these roles affect decision-making on peacekeeping deployments? Small state research cannot effectively answer these questions nor comprehensively explain what small states do in international affairs because it lacks analytical tools to link structure and agency. A theoretical approach grounded in role theory is better suited to understand the foreign policies of small states and re-evaluate their peacekeeping credentials. A model depicting the interaction between role socialisation and domestic role processes is constructed to guide four empirical analyses of recent peacekeeping decisions taken by Austrian and Belgian governments. This theoretical foundation allows the contention that small states' changing self-perceptions do not necessarily originate from internal ideational factors, as the norm entrepreneur argument suggests. Each case study traces how the interplay between external role demands and domestically conceived ideas about the state's position in an evolving peacekeeping system informs Austria's and Belgium's adjustment to new peace missions. Austria's decisions to withdraw from UNDOF in 2013, and to participate in EUFOR Chad 2007-2008, are telling cases of a small state adapting to new forms of peacekeeping through a reconfiguration of roles. This thesis also investigates the roles that have motivated the contributions made by two Belgian governments towards the Malian crisis, 2012-2013 and the 2006 Israeli-Hezbollah war. This project contributes to small state research by showing that these actors fulfil a broad range of functions in the international system. It also improves the way we explain small states' foreign policy actions by providing a dynamic framework capturing the relationship between structure and agency, and by delving into the decision-making processes of small states. Additionally, it adds to the peacekeeping literature by providing an original account as to why states, and in particular small states, contribute troops to missions operating under evolving conditions. Finally, inputs are made to the scholarship on role theory by exploring how state size influences role conceptions and investigating how role socialisation and domestic role dynamics interact to affect the roles and decisions of an under-studied category of states.

Medling är ett viktigt verktyg i verktygslådan för hantering av konflikter. Mycket av forskningen har fokuserat på externa aktörer som kommer från utanför konflikten och som är neutrala till konfliktparterna och sammanhanget, men interna aktörer som är partiska har mindre uppmärksamhet i medlingslitteraturen. Baserat på detta syftar studien till att förstå effekterna av olika typer av medlare, nämligen medling av extern-neutrala och interna-partiska medlare och effektivitetensom dessa medlare kan ha i fredsavtal. Baserat på detta är studiens forskningsfråga, Vilken medling är effektivaste för att nå ett hållbart fredsavtal i bräckliga stater, Inter-partisk eller Extern-neutral medling? För att svara på forskningsfrågan använder studien den kvalitativa metoden av fokuserad och strukturerad jämförelsemetod. Empirisk analys, som omfattar perioden 1991–1998, baserad på medlingsprocesserna i de två fallen av studien, nämligen södra Somalia och den självdeklarerade republiken Somaliland (norra Somalia) används. Studiens hypotes är att interna-partiska medlare är mer sannolikt att generera ett hållbart fredsavtal vilket bygger på förhandlingsteori där trovärdiga bärare av information kan förhindra informationsproblem och därmed skapa hållbar fred. Det empiriska resultatet av studien stödjer denna hypotes.