Este estudo apresenta indicações de mudanças paleoceanográficas ao longo dos últimos 25.000 anos na porção oeste do Oceano Atlântico Sul a partir do registro da variação de nanofósseis calcários em dois testemunhos de sedimento marinho da margem continental nordeste do Brasil. Outros indicadores foram incorporados às análises de nanofósseis calcários no intuito de melhor compreender as alterações observadas nas assembléias fósseis: 1) dados isotópicos de oxigênio de testas de foraminíferos planctônicos e bentônicos; 2) índice de temperatura e de nutrientes; 3) equação de paleoprodutividade e 4) análises estatísticas multivariadas. Os índices de temperatura e nutrientes foram, pela primeira vez, aplicados a nanofósseis calcários do Quaternário em amostras do Atlântico Sul. A integração dos resultados sugere que as principais características oceanográficas não sofreram alterações significativas nos últimos 25.000 anos, embora condições ambientais instáveis tenham sido registradas a partir da transição do Último Máximo Glacial - Holoceno. Durante o Último Máximo Glacial a região estudada sofreu pouca variação de temperatura, funcionando como um reservatório de calor. A variação da profundidade da termoclina/nutriclina foi considerada a principal resposta às oscilações climáticas, sendo relacionada às mudanças de intensidade dos ventos alísios. / This study focuses on changes in calcareous nannofossil assemblages as an evidence of paleoceanographic variability during the last 25,000 years in two deep sea piston cores from the northeastern Brazilian continental margin. To support reconstructing ancient marine environment others proxies have been applied along with the calcareous nannofossil analysis: 1) oxygen isotopic data from planktonic and benthic foraminifers\' tests; 2) temperature and nutrient indices; 3) paleoproductivity equation and 4) multivariate analysis. For the first time the temperature and nutrient indices were employed to Quaternary calcareous nannofossil from the South Atlantic Ocean. According to presented results major oceanographic features were stable in the last 25,000 years, although instable environmental conditions were recorded in the Last Glacial Maximum - Holocene boundary. During the Last Glacial Maximum the western tropical Atlantic seems to have experienced slight temperature changes and served as a heat and salt reservoir. Nutricline and thermocline depth variation was considered the most important response to climate changes largely related to Trade Winds strength oscillation.

A Basílica de Santa Maria Assunta, localizada em Torcello, uma das ilhas que compõem a Laguna de Veneza, abriga um programa iconográfico de três painéis em mosaico, caracterizados como bizantinos. Em um deles, na contrafachada, está figurado o painel do Juízo Final, nosso objeto de estudo. Produzido na segunda metade do século XI, ele inaugura (juntamente com o afresco de SantAngelo in Formis, na cidade de Cápua) a tradição de representação monumental desse tema iconográfico na Itália, aproximando-se do chamado modelo bizantino clássico, encontrado em Constantinopla a partir do século XI. Há, porém, algumas diferenças em relação aos exemplares conhecidos desse modelo bizantino, como o suporte e a localização em uma contrafachada de uma igreja. Assim, nossa preocupação nesta dissertação foi dupla: por um lado, analisar tais diferenças e, por outro, discutir o que levou à escolha deste tema ainda pouquíssimo comum para ornamentar uma igreja, buscando entender seus modos de funcionamento e as funções que desempenhava, tanto na igreja e em seu programa iconográfico quanto na própria sociedade veneziana da época de sua confecção. / The Basilica of Santa Maria Assunta, located in Torcello, one of the islands in the Venetian Lagoon, houses an iconographic program of three mosaic panels, characterized as Byzantine. In one of them, on the counter-façade, is figured the panel of the Last Judgment, our object of study. Produced on the second half of the eleventh century, it inaugurates (together with the fresco of Sant\'Angelo in Formis, in the city of Capua) the tradition of monumental representation of this iconographic theme in Italy, approaching the so-called \"classical Byzantine model\", found in Constantinople from the 11th century. There are, however, some differences from the known examples of this Byzantine model, such as the support and the location on a churchs counter-façade. Thus, our concern in this dissertation was twofold: on the one hand, to analyze such differences and, on the other hand, to discuss what led to the choice of this very uncommon subject to decorate a church, trying to understand its modes of functioning and the functions it performed, both in the church and in its iconographic program, as well as in Venetian society itself at the time of its confection.

Le sujet de ma thèse traite les changements paléoenvironnementaux et paléoclimatiques qui ont affecté les écosystèmes du Moyen Atlas marocain depuis la dernière période glaciaire, centrée autour de 25,000 cal BP. Les trois séquences sédimentaires étudiées dans cette thèse ont été prélevées le long d'un transect Nord-Sud dans le Moyen Atlas. Cette étude est basée sur une approche multi-bioindicateurs intégrant la palynologie, la géochimie élémentaire et la granulométrie afin de comprendre la dynamique des écosystèmes passés et de mettre en évidence les impacts anthropiques sur ces écosystèmes et leurs bassins versants. Les résultats obtenus montrent que durant la dernière période glaciaire et jusqu’au début de l’holocène, une végétation steppique a dominé les paysages du Moyen Atlas en réponse à des conditions climatiques froides et arides. Cependant, des populations de cèdres, de chênes et de pins ont persisté durant la période glaciaire dans des micro-refuges. Bien que le début de l’holocène révèle une expansion des chênes et des pins (principaux composants des écosystèmes forestiers méditerranéens), la steppe (composée d'armoise, de chénopodiacées et de graminées) a persisté jusqu’à 6.5 ka cal BP. Ces écosystèmes tolérant à la sécheresse reflètent un début de l’holocène chaud mais avec une quantité de précipitations annuelles assez réduite pour permettre l'expansion des forêts tel que nous l'observons en Europe et d’autres régions de la Méditerranée. Ce n'est qu'à partir de 6.5 ka cal BP que les forêts de cèdre s’installent aux altitudes des sites étudiés (autour de 1600m) et que des plantes aquatiques prolifèrent dans les marais ou nous avons effectué les sondages. Nous observons ensuite une nette régression du couvert arboré à partir de 4.5 ka cal BP, notamment les chênes décidus, et une expansion des taxons herbacés. Ceci est le résultat d’une tendance vers des conditions plus arides témoignant d'une installation du climat méditerranéen tel que nous le connaissons aujourd'hui. Le début des changements environnementaux liés à l'impact humain, à travers les données palynologiques et géochimiques, n'est enregistré qu’à partir de ca. 1500 cal BP. Les résultats obtenus dans cette thèse sont en accord avec ceux d'autres études paléoenvironnementales menées en Méditerranée autant pour la période glaciaire que pour le début des conditions arides à partir de 5.5 ka cal BP. / This thesis discusses the paleoenvironmental and paleoclimatic changes that have affected the ecosystems of the Moroccan Middle Atlas since the last glacial period, and focuses around 25000 cal BP. The three sedimentary sequences that have been studied in this thesis were taken along a North-South transect in the Middle Atlas. This study is based on a multi-bio-indicators approach, including palynology, geochemical elements and particle size, in order to better understand the dynamic of previous ecosystems and to highlight the human activities on these ecosystems and on their catchment areas.The results obtained show that during the last glacial period, and until the beginning of the Holocene, steppe vegetation was predominant in the Middle Atlas, in reaction to cold and arid climate conditions. However, populations of cedars, oaks and pine trees remained in micro-refugia. Although the beginning of the Holocene reveals an expansion of oaks and pines trees (the main components of Mediterranean forests ecosystems), the steppe (which is composed of Artemisia, Chenopodiaceae and grasses) persisted till 6.5 ka cal BP. These drought-tolerant ecosystems reflect a warm beginning of the Holocene, with an amount of precipitation that was low enough to allow the expansion of forests similar to those we can observe in Europe and other areas of the Mediterranean. It’s only since 6.5 ka cal BP that cedars forests have started to grow at the altitudes of the sites we studied (around 1600m), and that aquatic plants have proliferated in the marshes where we took our samples. We can then observe a sharp decline of tree cover, including deciduous oaks, starting 4.5 ka cal BP and an expansion of herbaceous taxa. These are the consequences of a tendency to conditions that were more arid, attesting the installation of the Mediterranean climate as we know it today. The first environmental changes linked to human impact have only been recorded, through palynology and biochemical data, from ca. 1500 cal BP. The results obtained in this thesis are in line with those obtained in other paleoenvironmental studies conducted in the Mediterranean area, for the glacial period as well as for the beginning of arid conditions starting 5.5 ka cal BP.

The focus of interest in this thesis is the social and personal trajectories of men and women who were born in the Soviet Union in the 1970-1980s and then, after growing up in post-Soviet Russia in the 1990s in an atmosphere of change and uncertainty, decided to exploit the opportunities to go abroad to study and work that started opening up in the early and mid-1990s. The thesis analyses these moves as the individual strategies of either escaping or waiting on the career insecurities in Russia, or consciously enhancing one's social standing and professional and educational capital. It traces their social and professional trajectories, showing that, apart from developing the desired expertise and gaining experience, these Russians went through intensive changes in their self-identifications and senses of belonging, including the acquisition of new habits of mobility, international social networks and cosmopolitan dispositions. This thesis argues that, while their Soviet-Russian cultural past and their belonging to a particular social group of 'Soviet intelligentsia' was still important to them, they continuously acquired new social, cultural and cosmopolitan forms of capital that influenced their coming back to Russia as different persons from their contemporaries who had stayed in the country. They brought with them new dispositions and new social practices resulting from their active comparisons of their lives in Russia and Britain, and in many respects they actively maintained their differences in creating clubs for returnees. While able to integrate successfully into the emerging Russian middle classes, they still expressed the cultural and intellectual heritage of the past Soviet intelligentsia, now reborn in the guise of Westernizing attitudes and practices, different degrees of cosmopolitan patriotism, intellectual pursuits, a quest for education and self-development, interest in world travel, an ethical concern for sustainability, opposition to excessive consumerism in Russia and conspicuous practices of status performance. The materials for this research were mainly gathered through the use of semi-structured in-depth interviews, one third of them longitudinal, with informants talking to the researcher several times during the course of fieldwork between 2007 and 2012. Some additional participant observation has been conducted in informal Russian circles in the UK and among returnees from Britain in Russia. This research consists of an ethnography with elements of a biographical approach. This has made the researcher attentive to the inclusion of a certain event within a person's whole biography, aimed at putting the period researched within the context of the past and future lives of the informant. The participants of this research were aged between 22 and 40 and belonged to a transition cohort generation (Miller 2000), as they had all passed their childhoods in the Soviet Union, their adolescence and teenage years coinciding with the period of dissolution of the USSR, with the transitional break up of one system and the formation of another, while their young adulthood developed in post-Soviet Russia. They were mainly single when they initiated their move to Britain, and had various professional profiles within the broadly defined groups of 'highly skilled' and 'highly educated', the latter term being preferred in this research. The dissertation includes an introduction, four ethnographic chapters, a conclusion and one appendix. The introduction presents the historical and research context, the methodology and the design of the study. The first chapter traces the professional and educational trajectories of participants, while the second chapter focuses on informants' spatial mobility and habits of extensive travel acquired during the move to Britain. The third chapter deals with the negotiation of informants' belonging to a particular cultural and social past, which is associated both with Russian-Soviet culture and with their social status as the children of Soviet-era intelligentsia. The fourth chapter argues that, while belonging to Soviet intelligentsia families was still important for informants' self-identifications in Britain, new social, cultural and cosmopolitan forms of capital were acquired during this period, resulting in new cosmopolitan dispositions, ethics and moral values, and new practices socially remitted (Levitt 2001) from Britain. The conclusion places this ethnography within the state-of-the-art research on the mobilities of Russians to the UK.

No setor da construção civil, tem ocorrido um aumento na utilização de sistemas industrializados, dentre eles sistemas construtivos metálicos, visto que o uso desses sistemas contribui para o aumento da velocidade de execução dos empreendimentos e para a redução de desperdícios. Esta mudança tem criado oportunidades para a aplicação de conceitos e métodos de gestão da produção, desenvolvidos em outras indústrias, tais como a Filosofia da Produção Enxuta, que tem trazido muitos benefícios ao setor da construção, tais como redução de desperdícios, aumento da produtividade e da confiabilidade nos prazos de entrega. Entretanto, há poucas pesquisas sobre a utilização de conceitos da produção enxuta no processo de PCP de obras de empresas que fornecem sistemas construtivos metálicos. O presente trabalho tem como objetivo geral propor diretrizes para a concepção e implementação de sistemas de Planejamento e Controle de Produção em obras de empresas que projetam, fabricam e montam sistemas construtivos metálicos. São também propostas adaptações no Sistema Last Planner ao contexto de montagem deste tipo de sistema. A estratégia de pesquisa adotada foi a pesquisa-ação, sendo desenvolvidos cinco estudos empíricos em obras de uma empresa líder neste setor. O trabalho iniciou pela realização de um diagnóstico relativo aos fluxos de materiais e informações entre os principais setores da empresa, assim como análise do processo de planejamento e controle existente no processo de montagem. Na sequência, foram definidas e implementadas melhorias no processo de PCP em três obras da empresa. Os principais resultados obtidos pela pesquisa estão relacionados à necessidade de ampliação do escopo do projeto do sistema de produção, à adaptação dos níveis de planejamento de médio e curto prazo do Sistema Last Planner para este contexto, assim como à necessidade de integração do planejamento e controle do processo de montagem a outros processos à montante da obra. São também propostos diferentes tipos de sistemas de planejamento e controle da produção, em função da complexidade e do tamanho da obra. / In the construction sector, there has been an increase on the use of industrialized building systems, including steel construction systems, due to the contribution of those systems in terms of reducing the duration of projects, and reduction of waste. This change has created opportunities for the application of production management concepts and methods that have been originated in other industries, such as the Lean Production Philosophy, which has brought several benefits for the construction sector, such as waste reduction, increase in productivity and reliability in delivery time. However, there have been only a few research studies on the application of Lean Production concepts on the production planning and control process of companies involved in the delivery of steel construction systems. The aim of this research work is to propose guidelines for the conception and implementation of production planning and control systems for projects delivered by companies that design, manufacture and assemble steel construction systems. Moreover, some adaptations in the Last Planner Systems are proposed for the context of assembling this type of system. Action research was the research strategy adopted in this investigation, which involved the development of five empirical studies in projects carried out by a Brazilian leading company. This investigation started by carrying out an analysis of the material and information flows among the main departments of the company, as well as by assessing the existing planning and control process for site assembly. Then, a set of improvements in that process were devised and implemented in three construction sites of the company. The main results of this research work are concerned with extending the scope of production system design, adapting the medium and short-term planning levels of the Last Planner System to this context, and integrating the planning and control process for site assembly with upstream processes. Moreover, different types of planning and control systems were proposed for different types of projects, according to their complexity and size.

Os sistemas de comunicação óptica por espaço livre, comumente denominados sistemas FSO (Free Space Optics), servem para estabelecer enlaces de comunicação do tipo wireless, ponto-a-ponto, a uma elevada taxa de dados e com alcances que podem variar de algumas centenas de metros a alguns quilômetros. O interesse pela tecnologia FSO tem sido estimulado pela necessidade de se fornecer soluções complementares às tradicionais (e.g. fibra óptica e RF) visando a atender à crescente demanda por conexões de banda larga. Algumas de suas aplicações mais importantes são a conexão de redes locais de computadores, a conexão de estações rádio base de telefonia móvel às centrais e o acesso de última milha. Embora a tecnologia FSO venha sendo empregada em pequena escala no Brasil, vislumbra-se o potencial de maior aplicação desta tecnologia em um futuro próximo, razão pela qual se propõe este estudo, focado no projeto de sistemas FSO. A principal contribuição deste trabalho é demonstrar uma possível solução para a realização de um enlace óptico operando em espaço livre, destinado a conectar duas redes locais de computadores Ethernet Rápida (100 Mbps). As seguintes atividades foram desenvolvidas: estudo das questões mais relevantes pertinentes ao projeto de sistemas FSO; projeto, construção e caracterização eletro-óptica de circuitos; montagem e demonstração do funcionamento de uma versão de testes do sistema, realizadas em laboratório; estudo de características associadas à transferência de radiação óptica de transmissor para receptor, envolvendo o balanço de potência para estimativa do alcance do enlace, sob condições atmosféricas ideais. Como resultado, obtivemos um sistema de comunicação do tipo full-duplex, operando no comprimento de onda de 850 nm em formato de modulação OOK, a uma taxa de dados efetiva de 125 Mbps. Com base na experiência obtida, melhoras ao sistema são sugeridas no final do trabalho. / Free space optical communication systems (FSO systems) provide wireless, point-to-point communication links at high data rates, at maximum distances ranging from hundreds of meters to several kilometers. The growing interest in FSO technology arises from the necessity of providing complementary and alternative solutions to those already adopted (eg. fiber optics and RF), aiming to satisfy the increasing demand for broadband connections. Some of its most important applications are connecting local area networks (LANs), backhauling wireless networks and providing last mile access. Although today FSO is not widely adopted in Brazil, the technology has the potential for being adopted in a greater scale in the near future, which is the reason we propose a study focused on issues related to the design of FSO systems. This work\'s main contribution is to demonstrate a possible solution for the construction of a FSO system intended to connect two Fast Ethernet LANs (100 Mbps). For this purpose, the following activities were developed: study of the main aspects related to FSO system design; design, construction and electrooptical characterization of circuits; mounting and demonstration, in the lab, of a test version of the system; study of characteristics related to radiation transfer from transmitter to receiver, involving the use of the link power budget for an estimation of the maximum distance achievable under ideal atmospheric conditions. The result is a full-duplex communication system that employs the 850 nm wavelength in OOK modulation format, operating at an effective bit rate of 125 Mbps. Based on the knowledge achieved, improvements to the system are suggested at the end of this work.

This dissertation analyzes the emergence of the Austro-Hungarian Bank (OeUB) as a modern lender of last resort (LLR) between 1868 and 1914. In order to evaluate policy responses to specific periods of financial distress, an in-depth knowledge of the context and dynamics at hand is indispensable. Chapter I sets the groundwork for this dissertation. It shows that bank failures during the Austro-Hungarian crisis of 1873 followed mainly from the break-down of a large repo market on the Viennese stock exchange. Credit institutions granted repo loans against securities that turned into highly illiquid and depreciated collateral. Banks that were forced to sell repossessed collateral in response to heavy funding withdrawals had to write-off substantial portions of their repo portfolios and thus incurred heavy losses. This chapter reinterprets the Austro-Hungarian crisis of 1873 as a historical "run on repo". It is the first study to examine a historical repo market crisis using microdata. I use semi-parametric survival analysis as well as stratification techniques new to the literature on bank distress to identify the causes of bank failures. Bank failures in 1873 did not spring from a pure liquidity problem, nor did they derive from a simple solvency shock. The complex roots of bank distress in 1873 posed difficult questions for policy-makers who needed to decide whether and how to intervene. Although central banks may be first-best candidates for the role of a LLR, they can also face constraints which obviate an elastic supply of liquidity during crises. Some of these constraints may be ideational, institutional or technical. Others are driven by market characteristics: quantity rationing can be the result of asymmetric information problems in financial markets. In Chapter II, I study a historical experiment implemented to overcome the specter of a credit rationing LLR during the Austro-Hungarian crisis of 1873. I explore bank-level information on treatment by a LLR mechanism designed as a public-private partnership between the central bank and market players. Drawing on inverse probability weighted regression adjustment (IPWRA) to tease out the causal effect of liquidity support, I show that this unconventional LLR was effective in mitigating bank distress: it worked as a remedy for the under-provision of a good particularly desirable in times of crises central bank liquidity. No matter how successful it is in calming financial distress and independently of the concrete form it takes, the LLR always comes at a cost. Moral hazard is a central issue in the literature on last resort lending. In Chapter III, I provide a new explanation for how central banks dealt with moral hazard historically. I focus on one specific component of central banks' risk frameworks: credit limits for discount window customers. I argue that credit limits as operationalized by the Austro-Hungarian Bank (OeUB) after 1878 constituted the backbone of an early form of microprudential regulation that was designed to check moral hazard in normal times. Credit limits empowered the Austro-Hungarian Bank to enforce minimum liquidity and capital standards for its counterparties at the discount window. Rather than contradicting the tenet of free lending in times of distress, credit limits functioned as "contingent rules": enforced in normal times, limits were increased or lifted during liquidity crises perceived as exogenous. Moreover, even during crises, the Bank did not simply relax limits for all credit institutions: it differentiated between banks depending on their fundamentals prior to the crisis. Chapter III provides the first economic interpretation and empirical analysis of the credit limit frameworks employed by central banks in the past.

Si, en littérature, le début scelle l’entrée dans un univers, la fin, lexicalement, porte toujours en elle à la fois la clôture et l’intention. Nous nous intéressons ici aux œuvres conclusives, aux textes qui ferment l'œuvre des auteurs. La narration y met en marche un mécanisme d’achèvement, de récapitulation – voire de déconstruction – de l’œuvre. Nous avons choisi d'étudier cinq auteurs (Reinaldo Arenas, Julio Cortázar, Juan Carlos Onetti, Augusto Roa Bastos et Ernesto Sábato) comme autant de voies différentes de tirer leur révérence littéraire. On examinera les différents chemins et modalités possibles de cette écriture finale. Dans ce travail, nous avons tenté de clarifier la notion d’« écriture testamentaire », souvent trop floue. Les propositions théoriques d’Edward Said autour du « style tardif » ont représenté une orientation importante à la délimitation de la notion. Le « tardif », par ses positionnements parfois radicaux, est ainsi venu secouer et questionner les caractéristiques plus vagues du « testamentaire » pour en dessiner, à travers des constantes et des variantes, une notion voisine et complémentaire. / Beginnings and ends are always decisive in literature as they represent the entrance to a universe and its closing. We chose here to study the last works of five important Latin American authors of the 20th century (Reinaldo Arenas, Julio Cortázar, Juan Carlos Onetti, Augusto Roa Bastos and Ernesto Sábato) as different ways to close their own work, using various modalities of final writing. The main focus of our attention will be on those various closing modalities. To illustrate the complexity of the notion, we will have to categorize it, from mechanism of fulfillment, completion, recapitulation – or even demolition - of the work. Edward W. Said’s theory on “late style” will help us to define and clarify the notion through its permanent features and variations.

A Basílica de Santa Maria Assunta, localizada em Torcello, uma das ilhas que compõem a Laguna de Veneza, abriga um programa iconográfico de três painéis em mosaico, caracterizados como bizantinos. Em um deles, na contrafachada, está figurado o painel do Juízo Final, nosso objeto de estudo. Produzido na segunda metade do século XI, ele inaugura (juntamente com o afresco de SantAngelo in Formis, na cidade de Cápua) a tradição de representação monumental desse tema iconográfico na Itália, aproximando-se do chamado modelo bizantino clássico, encontrado em Constantinopla a partir do século XI. Há, porém, algumas diferenças em relação aos exemplares conhecidos desse modelo bizantino, como o suporte e a localização em uma contrafachada de uma igreja. Assim, nossa preocupação nesta dissertação foi dupla: por um lado, analisar tais diferenças e, por outro, discutir o que levou à escolha deste tema ainda pouquíssimo comum para ornamentar uma igreja, buscando entender seus modos de funcionamento e as funções que desempenhava, tanto na igreja e em seu programa iconográfico quanto na própria sociedade veneziana da época de sua confecção. / The Basilica of Santa Maria Assunta, located in Torcello, one of the islands in the Venetian Lagoon, houses an iconographic program of three mosaic panels, characterized as Byzantine. In one of them, on the counter-façade, is figured the panel of the Last Judgment, our object of study. Produced on the second half of the eleventh century, it inaugurates (together with the fresco of Sant\'Angelo in Formis, in the city of Capua) the tradition of monumental representation of this iconographic theme in Italy, approaching the so-called \"classical Byzantine model\", found in Constantinople from the 11th century. There are, however, some differences from the known examples of this Byzantine model, such as the support and the location on a churchs counter-façade. Thus, our concern in this dissertation was twofold: on the one hand, to analyze such differences and, on the other hand, to discuss what led to the choice of this very uncommon subject to decorate a church, trying to understand its modes of functioning and the functions it performed, both in the church and in its iconographic program, as well as in Venetian society itself at the time of its confection.

As assembléias dos foraminíferos planctônicos fósseis de dois testemunhos amostrados do Atlântico tropical oeste representativo dos últimos 30.000 anos foram analisadas junto com estimativas de paleotemperatura superficial e ∂18O e ∂13C do foraminífero planctônico Globigerinoides ruber \'branca\'. Estes resultados mostraram que durante o Último Máximo Glacial e durante os eventos de resfriamento de curta duração Heinrich 1 and Younger Dryas o Atlântico tropical oeste manteve altas paleotemperaturas superficiais. Este estudo sugere que durante este período o Atlântico tropical oeste ocorreu uma acumulação de sal e clor nesta porção do Atlântico como conseqüência do enfraqueciemnto do transporte de calor e sal através do equador. Ao final destes eventos a intensificação do transporte de calor e sal foi restabelecido, baixando a temperatura superficial aos valores conhecidos atuamente. Este estudo sugere que o Atlântico tropical oeste atuou como um reservatório de calor e sal durante a deglaciação. / The planktonic foraminiferal assemblages of two piston cores from western tropical Atlantic covering the last 30,000 years have been analysed together with paleoceanographic ANN sea surface temperature reconstruction and ?18O and ?13C of the shallow dwelling planntonic foraminifera Globigerinoides ruber \'white\'. These proxies reveal that during the Last Glacial Maximum and during the Heinrich 1 and Younger Dryas cold events, the western tropical experienced warm periods. This study suggest that during these warm intervals a pronounced accumulation of heat and salt occurred at western tropical Atlantic, as a result of cross-equatorial heat and salt transport decrease. At the end of these events, the intensification of cross-equatorial heat and salt transport cooled and freshened the western tropical surface waters. This study suggests the western tropical Atlantic served as a heat and salt reservoir during deglaciation.