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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Análise empírica da formação de expectativas de inflação no Brasil : uma aplicação de redes neurais artificiais a dados em painel

Palma, Andreza Aparecida January 2007 (has links)
O objetivo principal deste trabalho é estudar empiricamente o processo de formação de expectativas inflacionárias no Brasil, no período recente (pós metas de inflação), através de um modelo conexionista, que aproxima a forma como os agentes fazem previsões. A coordenação das expectativas do mercado em relação à inflação futura é um aspecto crucial do regime de metas de inflação. Dessa forma, entender os fatores que afetam tais expectativas é de grande relevância para o direcionamento adequado da política monetária. Os dados para expectativas de inflação utilizados são provenientes da pesquisa FOCUS do Banco Central do Brasil, e constituem um painel de dados não balanceado. Os resultados obtidos nos permitem afirmar que a maior influência sobre as expectativas inflacionárias no período como um todo foi da volatilidade cambial, seguida pela variação no preço das commodities, pela defasagem de ordem um das expectativas, pela variação cambial e pela meta. Em menor magnitude, afetam as expectativas o resultado primário do governo, a defasagem de ordem dois e a taxa Selic. O comportamento desse efeito ao longo do tempo foi verificado através da análise de sensibilidade do produto da rede em resposta a cada uma das variáveis. No período de crise de confiança, há um expressivo descolamento das expectativas em relação à meta, com um aumento do efeito das demais variáveis. Resultado inverso ocorre no período pós-crise: o efeito da meta de inflação aumenta e das demais variáveis tende a se reduzir, ainda que em alguns casos tais efeitos sejam expressivos (como da defasagem de ordem um e da volatilidade cambial). Isso nos leva a concluir que o Banco Central vem consolidando sua credibilidade ao longo do tempo, mas que há ainda espaço para melhorias. / This work aims to empirically study the formation process of inflationary expectations in Brazil, in the recent period (after the introduction of the inflation targeting policy) by a connexionist model that approaches the way agents forecast. The coordination of market expectations in relation to the future inflation is a crucial aspect of the inflation targeting. This way, understanding the factors that affect such expectations has great relevance for the adequate aiming of the monetary policies. The data for inflation expectations used in this work are from the FOCUS research of the Brazilian Central Bank, and it constitutes a unbalanced data panel. The results obtained allow us to affirm that the biggest influence on the inflationary expectations in the period as a whole was from exchange rate volatility, followed by the commodities prices variation, by the first order lag of the expectations, by the exchange rate variation and by the target. In lesser magnitude, the primary result of the government, the second order lag and the Selic tax affect the expectations. The behavior of this effect throughout the time was verified through the analysis of sensitivity of the product of the network in reply to each one of the inputs. In the period of reliable crisis, there is an expressive shift of the expectations in relation to the target, with an increase of the effect of the other variables. Inverse result occurs in the after-crisis period: the effect of the inflation target increases and of the other variables tend to be reduced, despite in some cases such effect are expressive (as the first order lag and exchange rate volatility). Thus we may conclude that the Brazilian Central Bank has been consolidating its credibility throughout the time, but there is still an open space for improvements.
372

Um estudo sobre os modelos operacionais dos bancos centrais autônomos no mundo

Forjaz, Luiz Henrique Petersen 05 1900 (has links)
Made available in DSpace on 2008-05-13T13:48:25Z (GMT). No. of bitstreams: 1 2233.pdf: 464094 bytes, checksum: 6304ee0a64680524e3112ddd267fc553 (MD5) Previous issue date: 2007-05-31 / The bill of the Senate of no. 317 of 2003, that establishes the operational autonomy of the Central Bank of Brazil, is a great step towards an institutional modernization of the country. Being that approved autonomy, a crucial subject that proceed is how the institutional drawing of the Central Bank of Brazil will be. Which areas will be linked to BACEN and which areas will be out? Who will determine the goal? Who will be the members of COPOM? Those are just some subjects that appear when it is spoken in autonomy of the central bank. Several examples of autonomous central banks exist in the world and that study will analyze how those central banks operate, so that hereafter we can try to draw an institutional arrangement that adapts to the Brazilian needs. / O projeto de lei do Senado de Nº 317 de 2003, que estabelece a autonomia operacional do Banco Central do Brasil, é um grande passo em direção a uma modernização institucional do país. Sendo essa autonomia aprovada, uma questão crucial que se segue é como será o desenho institucional do Banco Central do Brasil. Quais áreas estarão ligadas ao BACEN e quais áreas estarão fora? Quem determinará a meta? Quem serão os membros do COPOM? Essas são apenas algumas questões que surgem quando se fala em autonomia do canco central. Existem diversos exemplos de bancos centrais autônomos no mundo e esse estudo irá analisar como esses cancos centrais operam, para que futuramente se possa tentar desenhar um arranjo institucional que se adapte as necessidades brasileiras.
373

Para além da inadequabilidade do regime monetário de metas de inflação no Brasil : evidências acerca da relação entre dinâmica de preços e produtividade na indústria de transformação

Piper, Denise January 2018 (has links)
A presente tese embasa-se na concepção de que a obtenção e a manutenção da estabilidade de preços na economia brasileira dependem não apenas da adoção de medidas pontuais de curto prazo, como também da contemplação da inflação, ao lado do crescimento econômico, como objetivos correlacionados no contexto de um projeto de desenvolvimento atinente a um horizonte ampliado de tempo. Em termos de políticas conjunturais de controles de preços, evidencia-se que, dado a inflação brasileira não consubstanciar-se em um fenômeno precipuamente de demanda, outras medidas, que não a mera elevação da taxa básica de juros, revelam-se necessárias; ademais, clarifica-se que aumentos nos juros, por seus significativos impactos contracionistas sobre a atividade econômica, comprometem a própria estabilidade futura de preços, consistindo, portanto, em uma conduta anti-inflacionária deveras ineficiente. No que tange ao longo prazo, argumenta-se que a inflação brasileira apresenta especificidades que a tornam variável dependente do processo de desenvolvimento econômico, social e institucional do País. Em assim sendo, entende-se que a dinâmica inflacionária brasileira vincula-se significativamente ao comportamento de determinados atributos intrínsecos ao setor produtivo nacional. Evidências empíricas obtidas neste trabalho a partir da estimação de um modelo SVAR concernente ao período que se segue a dezembro de 2009 mostram a existência de uma relação negativa entre inflação e produtividade na indústria de transformação, revelando-se tal relação, entretanto, inelástica, o que esclarece que o empresariado brasileiro tende a converter a maior parte dos ganhos de produtividade em expansões de mark-up, em vez de repassá-los primordialmente aos preços. Assim, constata-se que os problemas inflacionários enfrentados pela economia brasileira se mostram deveras complexos, e que sua resolução não depende apenas de vontade política. Desse modo, salta aos olhos a ineficiência do simplismo inerente ao Regime de Metas de Inflação no que tange à persecução da estabilidade de preços no Brasil. / The present thesis is based on the idea that obtaining and maintaining price stability in the Brazilian economy depends not only on the adoption of short-term measures, but also on the contemplation of inflation, alongside economic growth, as correlated objectives in the context of a development project related to an extended horizon of time. In terms of the cyclical policies of price control, it is evident that, given that Brazilian inflation is not mainly consubstantiated in a demand phenomenon, alternative measures, other than the mere increase of the benchmark interest rate, are necessary; in addition, it is clarified that increases in interest rates, due to their significant contractionary impacts on economic activity, jeopardize the future price stability, thus constituting an inefficient anti-inflationary behavior. With regard to the long-term, it is argued that Brazilian inflation shows specificities that make it a variable dependent of the economic, social and institutional development process of the Country. Accordingly, it is understood that the Brazilian inflationary dynamics is significantly linked to behavior of certain attributes intrinsic to the national productive sector. Empirical evidence obtained in this work from the estimation of a SVAR model concerning to the period after December 2009 shows the existence of a negative relationship between inflation and productivity in the manufacturing industry, revealing this relationship, however, inelastic, what clarifies that Brazilian businessmen tend to convert most of their productivity gains into mark-up expansions, instead of passing them along primarily to prices. So, it can be seen that the inflationary problems faced by the Brazilian economy are very complex, and that their resolution depends not only on political will. Therefore, the inefficiency of the simplicity inherent to the Inflation Targeting Regime in relation to the pursuit of price stability in Brazil is quite clear.
374

Gene targeting in Silkworm (Bombyx mori) by Engineered Endonucleases / Gene targeting in Silkworm (Bombyx mori) by Engineered Endonucleases

SAJWAN, Suresh Chandra Singh January 2013 (has links)
This thesis describes the establishment of a precise gene targeting methodology in the silkworm Bombyx mori by technologies based on engineered endonucleases. Two classes of engineered endonucleases, ZFNs and full length TALENs were used for creating DSBs at specified sites in the colour marker genes (BmBlos2 and Bmwh3). Direct embryo microinjection of engineered nucleases mRNA were performed and let the nuclease proteins to disrupt the functions of these marker genes by creating DSBs and inducing error prone NHEJ mechanism. These experiments showed that both ZFNs and TALENs could be used for targeted gene disruption in silkworms.
375

Understanding the “micro” in micro-targeting: an analysis of the 2018 Ontario provincial election

Yawney, Lauren 19 December 2018 (has links)
There is a breadth of research on micro-targeting in American elections, while the practice is under-researched in Canadian federal elections. Additionally, there is no academic commentary on micro-targeting at the Canadian provincial election level. This thesis draws on this gap in literature to investigate how micro-targeting is used at the provincial campaign level by parties and candidates. My research was conducted through an analysis of emails, Facebook ads and Facebook posts by the Liberal, Progressive Conservative and New Democratic Party candidates in 8 ridings in the 2018 Ontario election. I drew hypotheses about the types of “micro” appeals in provincial micro-targeting from the work of Kreiss (2017), Giasson and Small (2017), Marland and Matthews (2017), Munroe and Munroe (2018), Delacourt (2015) and Carty, Cross and Young (2000). From this research, I argue that provincial micro-targeting is nowhere near the level of specificity that is found in Canadian federal elections, let alone American elections. Parties rely on appeals to very broad groups and areas, such as occupations and “the North.” Parties do not use the information contained in voter management databases to target campaign appeals on social media or other media, and instead rely on these systems more for get-out-the-vote activities. This thesis contributes to the growing research on micro-targeting and the use of Facebook for political campaigning, while also remaining conscious to the fact that these technologies are constantly changing and advancing. / Graduate
376

Synthèse de nano-vecteurs dérivés des polydiacétylènes pour la co-délivrance d’un ARN interférent et d’un anticancéreux / Synthesis of polydiacetylenic nanovectors for intelligent co-delivery of siRNA and anticancer drug

Ripoll, Manon 11 December 2017 (has links)
En nanomédecine, une nouvelle approche consiste à développer des vecteurs synthétiques pour co-délivrer au sein d’une cellule tumorale, un anticancéreux ainsi qu’un siARN, capable de supprimer l’expression d’une protéine impliquée dans les mécanismes de résistance. Les travaux décrits dans ce manuscrit ont été consacrés à la synthèse de nano-vecteurs micellaires pour la délivrance simultanée de ces deux agents thérapeutiques. Une première partie décrit la synthèse et la formulation de micelles nanométriques diacétyléniques photopolymérisables conçues pour délivrer efficacement un siARN. Les propriétés d’encapsulation et de délivrance de ces micelles ont ensuite été étudiées in vitro et in vivo pour une application en thérapie combinatoire. Enfin, une dernière partie présente la fonctionnalisation par interaction électrostatique de ces vecteurs cationiques avec des anticorps préalablement modifiés par des oligonucléotides anioniques pour réaliser un ciblage actif des cellules tumorales. / In the nanomedecine field, a new approach consists in developing synthetic vectors able to co-deliver into a cancer cell, an antitumoral drug and siRNAs that target protein(s) involved in MDR. The work described in this manuscript was dedicated to the development of micellar nanovectors for the intracellular co-delivery of these two therapeutic agents. The first part details the synthesis and the formulation of nanometric photopolymerized diacetylenic micelles adapted for the delivery and intracellular release of the siRNA. Then, the encapsulation and delivery properties of these micelles, bearing histidine polar heads have been investigated in vitro and in vivo for the application of combination therapy. Finally, the last part presents the functionalization by electrostatic interaction of these cationic vectors with antibodies, priorly modified by anionic oligonucleotides. This original and versatile system allowed achieving an active targeting of tumoral cells.
377

Análise empírica da formação de expectativas de inflação no Brasil : uma aplicação de redes neurais artificiais a dados em painel

Palma, Andreza Aparecida January 2007 (has links)
O objetivo principal deste trabalho é estudar empiricamente o processo de formação de expectativas inflacionárias no Brasil, no período recente (pós metas de inflação), através de um modelo conexionista, que aproxima a forma como os agentes fazem previsões. A coordenação das expectativas do mercado em relação à inflação futura é um aspecto crucial do regime de metas de inflação. Dessa forma, entender os fatores que afetam tais expectativas é de grande relevância para o direcionamento adequado da política monetária. Os dados para expectativas de inflação utilizados são provenientes da pesquisa FOCUS do Banco Central do Brasil, e constituem um painel de dados não balanceado. Os resultados obtidos nos permitem afirmar que a maior influência sobre as expectativas inflacionárias no período como um todo foi da volatilidade cambial, seguida pela variação no preço das commodities, pela defasagem de ordem um das expectativas, pela variação cambial e pela meta. Em menor magnitude, afetam as expectativas o resultado primário do governo, a defasagem de ordem dois e a taxa Selic. O comportamento desse efeito ao longo do tempo foi verificado através da análise de sensibilidade do produto da rede em resposta a cada uma das variáveis. No período de crise de confiança, há um expressivo descolamento das expectativas em relação à meta, com um aumento do efeito das demais variáveis. Resultado inverso ocorre no período pós-crise: o efeito da meta de inflação aumenta e das demais variáveis tende a se reduzir, ainda que em alguns casos tais efeitos sejam expressivos (como da defasagem de ordem um e da volatilidade cambial). Isso nos leva a concluir que o Banco Central vem consolidando sua credibilidade ao longo do tempo, mas que há ainda espaço para melhorias. / This work aims to empirically study the formation process of inflationary expectations in Brazil, in the recent period (after the introduction of the inflation targeting policy) by a connexionist model that approaches the way agents forecast. The coordination of market expectations in relation to the future inflation is a crucial aspect of the inflation targeting. This way, understanding the factors that affect such expectations has great relevance for the adequate aiming of the monetary policies. The data for inflation expectations used in this work are from the FOCUS research of the Brazilian Central Bank, and it constitutes a unbalanced data panel. The results obtained allow us to affirm that the biggest influence on the inflationary expectations in the period as a whole was from exchange rate volatility, followed by the commodities prices variation, by the first order lag of the expectations, by the exchange rate variation and by the target. In lesser magnitude, the primary result of the government, the second order lag and the Selic tax affect the expectations. The behavior of this effect throughout the time was verified through the analysis of sensitivity of the product of the network in reply to each one of the inputs. In the period of reliable crisis, there is an expressive shift of the expectations in relation to the target, with an increase of the effect of the other variables. Inverse result occurs in the after-crisis period: the effect of the inflation target increases and of the other variables tend to be reduced, despite in some cases such effect are expressive (as the first order lag and exchange rate volatility). Thus we may conclude that the Brazilian Central Bank has been consolidating its credibility throughout the time, but there is still an open space for improvements.
378

Etude des performances de la politique économique : l'exemple du ciblage d'inflation en contexte de ruptures structurelles / Studies of the performance of economic policy : the case of inflation targeting in the context of structural

Sayari, Zied 06 December 2013 (has links)
Depuis sa première adoption en 1990, la politique de ciblage de l'inflation est devenue la politique monétaire la plus adoptée par les banques centrales aussi bien dans les économies développées ou émergentes. Cette priorité stratégique des autorités monétaires nous a conduits à réfléchir sur l'efficacité de ce choix. L'objectif de cette thèse est alors étudier la performance économique de cette politique économique surtout en cas de ruptures structurelles. Le premier chapitre présente l'approche théorique de ce travail en mettant l'accent sur ce débat de performance et l'intérêt à adopter cette politique de ciblage d'inflation afin de maitriser sa volatilité. L'approche empirique de cette thèse cherche à vérifier la performance de ce passage. Le second chapitre traduit l'efficacité du nouveau régime en étudiant son effet sur la dynamique de l'inflation, la croissance et certains indicateurs agissant sur la conjoncture macroéconomique. Ce travail explore également l'existence des différents points de ruptures structurelles. Le troisième chapitre illustre l'existence de ces dates de changement correspondant au changement de régime. La présente étude montre d'un côté qu'il y a performance économique suite au changement de régime. D'un autre côté, les résultats prouvent l'existence de multitude points de changement de rupture structurelle qui coïncident avec la mise en œuvre de la nouvelle politique de ciblage d'inflation. / Since its first introduction in 1990, the policy of inflation targeting has become the most adopted monetary policy by central banks in both developed and emerging economies. This strategic priority of monetary policy has led us to think the effectiveness of this choice. The objective of this thesis is then to study the economic performance of this economic policy especially in the case of structural interruptions. The first chapter presents the theoretical approach of this work focusing on performance and the necessity of adopting this policy in order to control its volatility. The empirical approach of this thesis aims to verify the performance of this transition. The second chapter shows the effectiveness of the new system by studying its effect on the inflation dynamics, the growth and indicators which affect the macroeconomic environment. This work also explores the existence of different points of structural interruptions. The third chapter illustrates the existence of these date changes corresponding to the regime switching. The present study reveals on one side that there is economic performance following the regime change. On the other hand, the results confirm the existence of many structural break points which coincide with the implementation of the new policy of inflation targeting.
379

Synthèse de vecteurs peptidiques non-viraux : vectorisation et ciblage tumoral / Synthesis of non viral peptide vectors : targeting of cancer

Claron, Michaël 29 November 2013 (has links)
Dans l’optique de développer de nouveaux agents bio-inspirés pour la détection et/ou le traitement des cellules cancéreuses, nos travaux se sont tournés vers la synthèse de macromolécules peptidiques complexes ayant la capacité de reconnaître les cellules tumorales. Ces travaux visent à développer des molécules permettant de cibler des particularités cellulaires présentes sur les cellules tumorales dans le but d’obtenir un traitement personnalisé via une vectorisation active permettant une augmentation de l'efficacité thérapeutique et une réduction intrinsèque de la toxicité du traitement. Pour cela, ces biomolécules doivent posséder à la fois un site de reconnaissance pour la liaison avec des protéines présentes à la surface de la cellule cible et un ou plusieurs éléments utilisés pour détecter et/ou détruire la cible. Ces systèmes ont été élaborés à partir d'un châssis moléculaire cyclodécapeptidique présentant des propriétés conformationnelles particulières. Plusieurs approches ont été envisagées. La première a consisté à rechercher de nouveaux ligands de récepteurs tumoraux en s'inspirant du domaine de reconnaissance d'un anticorps monoclonal thérapeutique. Dans ce contexte, nous avons proposé la conception de mimes du Rituximab ciblant l'antigène CD20 utilisé dans le traitement des lymphomes Non-Hodgkinien. Dans la seconde approche, nous avons développé des vecteurs destinés à des applications d'imagerie tumorale. Pour cela, des châssis multivalents présentant des ligands peptidiques RGD ciblant l'intégrine alpha-v-beta-3 ont été conjugués avec différents agents de détection puis évalués par des techniques d'imagerie telles que la TEP, la TEMP et l’imagerie optique. Toujours dans un but de diagnostic des cellules tumorales, nous nous sommes par la suite tournés vers l’application à la capture cellulaire. Pour cela, une surface d’or à été modifiée via la formation d’une monocouche organisée SAM (« Self-assembled monolayer ») présentant des cyclodextrines. Un gabarit peptidique adéquat a ainsi permis la capture et le relargage sélectif de cellules tumorales mesurées par la technique de microbalance à quartz. Ces mêmes vecteurs, validés pour le diagnostic ont par la suite été couplés à des peptides cytotoxiques issus d’une protéine pro-apoptotique « Bax ». Enfin, une dernière partie a été consacrée à la recherche de nouveaux composés comportant plusieurs éléments de ciblage tumoraux. Ces molécules présentent deux ligands de ciblage des récepteurs surexprimés sur la membrane et peuvent ainsi permettre une meilleure sélectivité vis-à-vis des tissus tumoraux. / In order to develop new agents for cancer diagnosis and treatment, our work aims to synthesize complex peptide macromolecules that are able to specifically recognize cancer cells. Our goal is to increase the therapeutic efficiency and reduce the toxicity of currently available drugs using "targeted strategies". In this context, we designed sophisticated macromolecules encompassing a cell recognition domain and one or several components used to detect and/or destroy the target. This system was prepared starting from a cyclodecapeptidic scaffold presenting particular conformational properties. Different approaches were considered. First of all our work was to investigate new tumor receptor ligands based on the recognition domain of a therapeutics monoclonal antibody. We proposed the design of Rituximab mimics which targets the CD20 antigen used for the treatment of Non-Hodgkin lymphoma. In a second approach, we prepared new vectors for tumor imaging. For this purpose, multivalent scaffolds containing RGD peptide that targets alpha-v-beta-3 integrin were combined with several detection elements and evaluated by using PET, SPECT and optical imaging techniques. We also used this peptide vector for the selective cell capture and release from flowing suspensions, using a gold surface modified with a cyclodextrin-containing self-assembled monolayer (SAM). A scaffold containing ferrocenyl and -RGD- ligands permitted the selective capture and release of tumor cells. This experiment was monitored by QCM-D. This vector has been next grafted to a cytotoxic peptide that was discovered from a pro-apoptotic protein named “Bax”. Finally, we designed new molecules which include an additional ligand for the cell’s surface to increase the selectivity and the affinity of tumor tissue.
380

Quem atinge as metas? Determinantes do sucesso das metas de inflação / Who hits the targets?

Acauã Brochado 02 December 2009 (has links)
O sistema de metas de inflação é considerado por muitos o regime monetário mais moderno em prática no mundo, um dos pilares fundamentais da política macroeconômica atual. Muitos estudos foram feitos sobre esse sistema, mas até o momento faltavam pesquisas empíricas sobre uma questão chave: quais são os determinantes do sucesso do sistema de metas de inflação? Mais especificamente, será que um país com dívida menor, superávit fiscal maior e mais aberto ao comércio exterior tem mais chances de ser bem sucedido sob o regime de metas? Este trabalho procura responder empiricamente a essa questão analisando quais variáveis macroeconômicas fazem com que esse regime funcione melhor em determinado país, ou seja, o que afeta a chance de que a inflação se mantenha próxima à meta. A análise econométrica é feita a partir de um painel de dados de diversas variáveis. Entre outras, o painel contém a situação fiscal do governo, o nível de abertura comercial e o estoque de reservas internacionais, para os diversos países que utilizam ou utilizaram esse regime, durante o período de adoção. Os cálculos mostram que nenhuma dessas variáveis apresentou significância estatística na determinação do sucesso do regime. / Inflation targeting is considered by many as the most modern monetary regime in practice in the world, one of the fundamentals of todays macroeconomic policy. Many empirical works have been done on this theme, but, until now, am important question remained unanswered: what are the determinants of the inflation targeting regime success? More precisely, will a country with lower debt, higher fiscal surplus, and a more open economy have better chances in being successful under IT? This paper tries to empirically answer this analyzing which macroeconomic variables help the regime functioning in a given country, that is, what affects the chances that inflation keeps on track. The econometric analysis is made with a panel data approach. Among others, the panel contains the government fiscal situation, the level of commercial openness, and the international reserves stock, for the various countries that are, or were for some time, under inflation targeting, during the period of adoption. The calculations show that these variables are not statistically significant in the determination of the regime success.

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