869 resultados para Expectations hypothesis of term struscture of interest rates


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Electron-impact scattering data for argon and its ions continue to be of interest in studies of magnetically confined plasmas. In an earlier paper, Griffin et al (1997 J. Phys. B: At. Mol. Opt. Phys. 30 3543) employed the results of 28-term and 40-term R-matrix calculations of electron-impact excitation in Ar+ to carry out a collisional-radiative modelling study of the impurity influx of argon in tokamaks. We have now completed a 452-term R-matrix with pseudo-states (RMPS) calculation of electron-impact excitation for Ar+ in order to provide more accurate excitation data; using these improved data, we have repeated the modelling studies presented in the earlier paper. We compare our excitation data, as well as the results of the collisional radiative calculations, with those arising from the 40-term R-matrix calculation and find significant differences.

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Inelastic electron scattering from light atomic species is of fundamental importance and has significant applications in fusion-plasma modeling. Therefore, it is of interest to apply advanced nonperturbative, close-coupling methods to the determination of electron-impact excitation for these atoms. Here we present the results of R matrix with pseudostate (RMPS) calculations of electron-impact excitation cross sections through the n=4 terms in Be, Be+, Be2+, and Be3+. In order to determine the effects of coupling of the bound states to the target continuum in these species, we compare the RMPS results with those from standard R-matrix calculations. In addition, we have performed time-dependent close-coupling calculations for excitation from the ground and the metastable terms of Be+ and the metastable term of Be3+. In general, these results are found to agree with those from our RMPS calculations. The full set of data resulting from this work is now available on the Oak Ridge National Laboratory Controlled Fusion Atomic Data Center web site, and will be employed for collisional-radiative modeling of Be in magnetically confined plasmas.

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Coastal and estuarine landforms provide a physical template that not only accommodates diverse ecosystem functions and human activities, but also mediates flood and erosion risks that are expected to increase with climate change. In this paper, we explore some of the issues associated with the conceptualisation and modelling of coastal morphological change at time and space scales relevant to managers and policy makers. Firstly, we revisit the question of how to define the most appropriate scales at which to seek quantitative predictions of landform change within an age defined by human interference with natural sediment systems and by the prospect of significant changes in climate and ocean forcing. Secondly, we consider the theoretical bases and conceptual frameworks for determining which processes are most important at a given scale of interest and the related problem of how to translate this understanding into models that are computationally feasible, retain a sound physical basis and demonstrate useful predictive skill. In particular, we explore the limitations of a primary scale approach and the extent to which these can be resolved with reference to the concept of the coastal tract and application of systems theory. Thirdly, we consider the importance of different styles of landform change and the need to resolve not only incremental evolution of morphology but also changes in the qualitative dynamics of a system and/or its gross morphological configuration. The extreme complexity and spatially distributed nature of landform systems means that quantitative prediction of future changes must necessarily be approached through mechanistic modelling of some form or another. Geomorphology has increasingly embraced so-called â˜reduced complexityâ models as a means of moving from an essentially reductionist focus on the mechanics of sediment transport towards a more synthesist view of landform evolution. However, there is little consensus on exactly what constitutes a reduced complexity model and the term itself is both misleading and, arguably, unhelpful. Accordingly, we synthesise a set of requirements for what might be termed â˜appropriate complexity modellingâ of quantitative coastal morphological change at scales commensurate with contemporary management and policy-making requirements: 1) The system being studied must be bounded with reference to the time and space scales at which behaviours of interest emerge and/or scientific or management problems arise; 2) model complexity and comprehensiveness must be appropriate to the problem at hand; 3) modellers should seek a priori insights into what kind of behaviours are likely to be evident at the scale of interest and the extent to which the behavioural validity of a model may be constrained by its underlying assumptions and its comprehensiveness; 4) informed by qualitative insights into likely dynamic behaviour, models should then be formulated with a view to resolving critical state changes; and 5) meso-scale modelling of coastal morphological change should reflect critically on the role of modelling and its relation to the observable world.

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The main aim of this chapter is to analyze the social and political effects of dynastic marriages between the Portuguese and Castilian-Aragonese crowns on the configuration of transnational, aristocratic families during the sixteenth and seventeenth centuries. To illustrate these questions we have chosen to follow the Soares de Alarcão family (known in Spain as Suárez de Alarcón) and the paths it took between the royal houses of Portugal and Castile for seven generations. The working hypothesis of the chapter is that the identity of the Iberian nobility during this era was characterized by a shared noble culture rather than by any particular features derived from the familyâs land of origin. That assumption allows us to discuss whether the use of a particular language or culture indicates ties or political loyalties based on criteria of nationality, or, at the very least, place of birth. Therefore, this essay discusses the miscegenation of Iberian nobilities derived from dynastic marriages. It articulates the structural characteristics of this group and its political impact with the individual trajectories and historical contexts in which they developed. While these topics can be of interest for the comprehension of Portuguese early modern history, they can also help us to reflect more broadly on processes of identity construction.

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Aim There is growing interest in the contribution of public-private partnerships (PPPs) bridging the shortage of financial resources and management expertise in developing public healthcare infrastructure. However, few studies have evidenced PPPsâ ability in increasing efficiency in public procurement of primary healthcare infrastructure. The aim of this study was to assess to what extent PPPs would increase efficiency in public procurement of primary healthcare facilities. Subject and Methods A qualitative analysis, adopting a realistic research evaluation method, used data collected from a purposive sample of public (n=23) and private sector staff (n=2) directly involved in the UK National Health Service Local Improvement Finance Trust (LIFT). Results We find a positive association of LIFT helping to bridge public sector capital shortages for developing primary care surgeries. LIFT is negatively associated with inefficient procurement because it borrows finance from private banks, leaving public agencies paying high interest rates. The study shows that some contextual factors and mechanisms in LIFT play a major part in obstructing public staff from increasing procurement efficiency. Conclusion PPPâs ability to increase efficiency may be determined by contextual factors and mechanisms that restrict discretion over critical decisions by frontline public sector staff. Developing their capacity in monitoring PPP activities may make partnerships more efficient.

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The European sea bass, Dicentrarchus labrax, is one of the most important marine species cultivated in Southern Europe and has not benefited from selective breeding. One of the major goals in the sea bass (D. labrax) aquaculture industry is to understand and control the complexity of growth associated traits. The aim of the methodology developed for the studies reported in the thesis was not only to establish genetic and genomic resources for sea bass, but to also develop a conceptual strategy to efficiently create knowledge in a research environment that can easily be transferred to the aquaculture industry. The strategy involved; i) establishing an annotated sea bass transcriptome and then using it to, ii) identify new genetic markers for target QTL regions so that, iii) new QTL analysis could be performed and marker based resolution of the DNA regions of interest increased, and then iv) to merge the linkage map and the physical map in order to map the QTL confidence intervals to the sea bass genome and identify genes underlying the targeted traits. Finally to test if genes in the QTL regions that are candidates for divergent growth phenotypes have modified patterns of transcription that reflects the modified whole organism physiology SuperSAGE-SOLiD4 gene expression was used with sea bass with high growth heterogeneity. The SuperSAGE contributed to significantly increase the transcriptome information for sea bass muscle, brain and liver and also led to the identification of putative candidate genes lying in the genomic region of growth related QTL. Lastly all differentially expressed transcripts in brain, liver and muscle of the European sea bass with divergent specific growth rates were mapped to gene pathways and networks and the regulatory pathways most affected identified and established the tissue specific changes underlying the divergent SGR. Owing to the importance of European sea bass to Mediterranean aquaculture and the developed genomics resources from the present thesis and from other studies it should be possible to implement genetic selection programs using marker assisted selection.

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Tese de doutoramento, Geologia (Geologia Económica e do Ambiente), Universidade de Lisboa, Faculdade de Ciências, 2014

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Thesis (Ph.D.)--University of Washington, 2013

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Writing in the late 1980s, Nancy gives as examples of the "recent fashion for the sublime" not only the theoreticians of Paris, but the artists of Los Angeles, Berlin, Rome, and Tokyo. At the beginning of the twenty-first century, the sublime may of course no longer seem quite so "now" as it did back then, whether in North America, Europe, or Japan. Simon Critchley, for one, has suggested that, at least as regards the issue of its conceptual coupling to "postmodernism," the "debate" concerning the sublime "has become rather stale and the discussion has moved on." Nonetheless, if that debate has indeed "moved on"-and thankfully so-it is not without its remainder, particularly in the very contemporary context of a resurgence of interest in explicitly philosophical accounts of art, in the wake of an emergent critique of cultural studies and of the apparent waning of poststructuralism's influence-a resurgence that has led to a certain "return to aesthetics" in recent Continental philosophy and to the work of Kant, Schelling, and the German Romantics. Moreover, as Nancy's precise formulations suggest, the "fashion" [mode] through which the sublime "offers itself"-as "a break within or from aesthetics"-clearly contains a significance that Critchley's more straightforward narration of shifts in theoretical chic cannot encompass. At stake in this would be the relation between the mode of fashion and art's "destiny" within modernity itself, from the late eighteenth century onwards. Such a conception of art's "destiny," as inextricably linked to that of the sublime, is not unique to recent French theory. In a brief passage in Aesthetic Theory, Adorno also suggests that the "sublime, which Kant reserved exclusively for nature, later became the historical constituent of art itself.... [I]n a subtle way, after the fall of formal beauty, the sublime was the only aesthetic idea left to modernism." As such, although the term has its classical origins in Longinus, its historical character for "us," both Nancy and Adorno argue, associates it specifically with the emergence of the modern. As another philosopher states: "It is around this name [of the sublime] that the destiny of classical poetics was hazarded and lost; it is in this name that ... romanticism, in other words, modernity, triumphed."

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Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores

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Are return migrants more productive than non-migrants? If so, is it a causal effect or simply self-selection? Existing literature has not reached a consensus on the role of return migration for origin countries. To answer these research questions, an empirical analysis was performed based on household data collected in Cape Verde. One of the most common identification problems in the migration literature is the presence of migrant self-selection. In order to disentangle potential selection bias, we use instrumental variable estimation using variation provided by unemployment rates in migrant destination countries, which is compared with OLS and Nearest Neighbor Matching (NNM) methods. The results using the instrumental variable approach provide evidence of labour income gains due to return migration, while OLS underestimates the coefficient of interest. This bias points towards negative self-selection of return migrants on unobserved characteristics, although the different estimates cannot be distinguished statistically. Interestingly, migration duration and occupational changes after migration do not seem to influence post-migration income. There is weak evidence that return migrants from the United States have higher income gains caused by migration than the ones who returned from Portugal.

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To study the macroeconomic effects of unconventional monetary policy across the different countries of the eurozone, I develop an identification scheme to disentangle conventional from non-conventional policy shocks, using futures contracts on overnight interest rates and the size of the European Central Bank balance sheet. Setting these shocks as endogenous variables in a structural vector autoregressive (SVAR) model, along with the CPI and the employment rate, estimated impulse response functions of policy to macroeconomic variables are studied. I find that unconventional policy shocks generated mixed effects in inflation but had a positive impact on employment, with the exception of Portugal, Spain, Greece and Italy where the employment response is close to zero or negative. The heterogeneity that characterizes the responses shows that the monetary policy measures taken in recent years were not sufficient to stabilize the economies of the eurozone countries under more severe economic conditions.

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Directed Research Internship

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In this paper, we analyze the behavior of real interest rates over the long-run using historical data for nine developed economies, to assess the extent to which the recent decline observed in most advanced countries is at odds with the past data, as suggested by the Secular Stagnation hypothesis. By using data from 1703 and performing stationarity and structural breaks tests, we find that the recent decline in interest rates is not explained by a structural break in the time series. Our results also show that considering long-run data leads to different conclusions than using short-run data.

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In this work we are going to evaluate the different assumptions used in the Black- Scholes-Merton pricing model, namely log-normality of returns, continuous interest rates, inexistence of dividends and transaction costs, and the consequences of using them to hedge different options in real markets, where they often fail to verify. We are going to conduct a series of tests in simulated underlying price series, where alternatively each assumption will be violated and every option delta hedging profit and loss analysed. Ultimately we will monitor how the aggressiveness of an option payoff causes its hedging to be more vulnerable to profit and loss variations, caused by the referred assumptions.