988 resultados para Theoretical-methodological dimension
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This paper examines the issue of fiscal sustainability in emerging market countries and industrial countries. We highlight the importance of the time series properties of the primary surplus and debt, and find evidence of a positive long run relationship. Consequently we emphasise, that especially for emerging markets, it is important to recognise the implications of global capital market shocks for fiscal sustainability, a relationship which has hitherto been ignored in the empirical literature. Using a factor model we demonstrate that the relationship between deficit and debt is conditional upon a global factor and we suggest that this global factor is related to world-wide liquidity. We also demonstrate that this acts as a constraint on emerging market economies’ fiscal policy.
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We extend the linear reforms introduced by Pf¨ahler (1984) to the case of dual taxes. We study the relative effect that linear dual tax cuts have on the inequality of income distribution -a symmetrical study can be made for dual linear tax hikes-. We also introduce measures of the degree of progressivity for dual taxes and show that they can be connected to the Lorenz dominance criterion. Additionally, we study the tax liability elasticity of each of the reforms proposed. Finally, by means of a microsimulation model and a considerably large data set of taxpayers drawn from 2004 Spanish Income Tax Return population, 1) we compare different yield-equivalent tax cuts applied to the Spanish dual income tax and 2) we investigate how much income redistribution the dual tax reform (Act ‘35/2006’) introduced with respect to the previous tax.
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Vaccines have been used as a successful tool in medicine by way of controlling many major diseases. In spite of this, vaccines today represent only a handful of all infectious diseases. Therefore, there is a pressing demand for improvements of existing vaccines with particular reference to higher efficacy and undisputed safety profiles. To this effect, as an alternative to available vaccine technologies, there has been a drive to develop vaccine candidate polypeptides by chemical synthesis. In our laboratory, we have recently developed a technology to manufacture long synthetic peptides of up to 130 residues, which are correctly folded and biologically active. This paper discusses the advantages of the molecularly defined, long synthetic peptide approach in the context of vaccine design, development and use in human vaccination.
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Estudi realitzat a partir d’una estada al Physics Department de la New York University, United States, Estats Units, entre 2006 i 2008. Una de les observacions de més impacte en la cosmologia moderna ha estat la determinació empírica que l’Univers es troba actualment en una fase d’Expansió Accelerada (EA). Aquest fenòmen implica que o bé l’Univers està dominat per un nou sector de matèria/energia, o bé la Relativitat General deixa de tenir validesa a escales cosmològiques. La primera possibilitat comprèn els models d’Energia Fosca (EF), i el seu principal problema és que l’EF ha de tenir propietats tan especials que es fan difícils de justificar teòricament. La segona possibilitat requereix la construcció de teories consistents de Gravetat Modificada a Grans Distàncies (GMGD), que són una generalització dels models de gravetat massiva. L’interès fenomenològic per aquestes teories també va resorgir amb l’aparició dels primers exemples de models de GMGD, com ara el model de Dvali, Gabadadze i Porrati (DGP), que consisteix en un tipus de brana en una dimensió extra. Malauradament, però, aquest model no permet explicar de forma consistent l’EA de l’Univers. Un dels objectius d’aquest projecte ha estat establir la viabilitat interna i fenomenològica dels models de GMGD. Des del punt de vista fenomenològic, ens hem centrat en la questió més important a la pràctica: trobar signatures observacionals que permetin distingir els models de GMGD dels d’EF. A nivell més teòric, també hem investigat el significat de les inestabilitats del model DGP.L’altre gran objectiu que ens vam proposar va ser la construcció de noves teories de GMGD. En la segona part d’aquest projecte, hem elaborat i mostrat la consistència del model “DGP en Cascada”, que generalitza el model DGP a més dimensions extra, i representa el segon model consistent i invariant-Lorentz a l’espai pla conegut. L’existència d’altres models de GMGD més enllà de DGP és de gran interès atès que podria permetre obtenir l’EA de l’Univers de forma purament geomètrica.
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The progressive development of Alzheimer's disease (AD)-related lesions such as neurofibrillary tangles,amyloid deposits and synaptic loss within the cerebral cortex is a main event of brain aging.Recent neuropathologic studies strongly suggested that the clinical diagnosis of dementia depends more on the severity and topography of pathologic changes than on the presence of a qualitative marker. However, several methodological problems such as selection biases, case-control design,density-based measures, and masking effects of concomitant pathologies should be taken into account when interpreting these data. In last years, the use of stereologic counting permitted to define reliably the cognitive impact of AD lesions in the human brain. Unlike fibrillar amyloid deposits that are poorly or not related to the dementia severity, the use of this method documented that total neurofibrillary tangles and neuron numbers in the CA1 field are the best correlates of cognitive deterioration in brain aging. Loss of dendritic spines in neocortical but not hippocampal areas has a modest but independent contribution to dementia. In contrast, the importance of early dendritic and axonal tau-related pathologic changes such as neuropil threads remains doubtful. Despite these progresses, neuronal pathology and synaptic loss in cases with pure AD pathology cannot explain more than 50% of clinical severity. The present review discusses the complex structure/function relationships in brain aging and AD within the theoretical framework of the functional neuropathology of brain aging.
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This paper analyses RE macromodels from the methodological perspective. It proposes a particular property, robustness, which should be considered a necessary feature of scienti cally valid models in economics, but which is absent from many RE macromodels. To restore this property many macroeconomists resort to detailed and implausible assumptions, which take their models a long way from simple Rational Expectations. The paper draws attention to the problems inherent in the technique of local linearisation and concludes by proposing the use of nonlinear models, analysed globally.
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"Vegeu el resum a l'inici del document del fitxer adjunt."
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We provide field experimental evidence of the effects of monitoring in a context where productivity is multi-dimensional and only one dimension is monitored and incentivised. We hire students to do a job for us. The job consists of identifying euro coins. We study the effects of monitoring and penalising mistakes on work quality, and evaluate spillovers on non- incentivised dimensions of productivity (punctuality and theft). We .nd that monitoring improves work quality only if incentives are large, but reduces punctuality substantially irrespectively of the size of incentives. Monitoring does not affect theft, with ten per cent of participants stealing overall. Our setting also allows us to disentangle between possible theoretical mechanisms driving the adverse effects of monitoring. Our .ndings are supportive of a reciprocity mechanism, whereby workers retaliate for being distrusted.
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The work of this thesis would like to investigate two particular questions about the care of underage: on the one hand, the maltreatment, and the mother's desire on the other hand. About the first, this proposal try to underscore the elaborate irregularity and disparity related to this phenomenon and his historical evolution. The objective's thesis propose to underline that the abuse crosses the crisis of educational dimension inside and outside the family. We are talking about a type of crisi that places at the origin of a specific clinic and that it is about the maltreatment designated, at the same time, to cope with the educational void and with the ill-treated under age's hardships. The so-called clinic of the maltreatment horns, therefore, with the purpose to join and to set in order the normative and educational aspects. However, the prescriptive requirement is intended to measure against the same one crisis in a paradoxical way; the laws and the juveniles court must make up for the lack absence of the rules that characterized the maltreatment, getting around to use the typical reference that traditionally were been at the base of the educational way's construction. The same crimes on underage often found in the father the responsibility. The requirements and the therapeutic needs has utilized the theoretical construct of the trauma as the key line of clinical practice. On the one hand, the trauma was been paired controversially to the psychoanalytical concepts as the notion of the phantom, in the same manner that the objective truth is been opposed to the notion of the imagination and fantasy; on the other hand, the trauma was gotten to be the mark and the characteristic that defined the individual identity of the mistreated persons, regardless of the person's clinical structure or, generally, regardless of the their individual position. Both the normative demand and therapeutic converge on the idealization of the imaginary figure that is able to supply to every type of maltreatment: the mother. This position is connected on theoretical construct well-established in the mythology, that associated the mother figure to a natural dimension; this is related to the second point at issue: the mother's desire. The awareness of the mother figure in natural and idealized terms describes accusingly and negatively the trauma, without seeing the difference between trauma that helps to give a structure to the individual position from the trauma solely devastating. The mother's mythology, therefore, is in an evident antagonism with the female figure and woman's sexuality. In these way the maltreatment's clinic suggests that a woman is able to be a mother only when she doesn't appreciate the rule of female. This situation preclusives a comparison with own sexuality and gives to the women a complex of castration. The clinic cases reported highlight as these difficulties are the expression of the familiarity's heredity that wasn't been sufficiently elaborated. This condition (into the relation between mother and his child) turn the infant in the incapacity to symbolized and it doesn't help him to accede to the positive trauma, to the language and to the edipic rule; this is the reason why the child toils difficulties to approach to own personality and to orient himself in the relation with his body, with the body of the adults and the same age children.
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Vector Autoregressive Moving Average (VARMA) models have many theoretical properties which should make them popular among empirical macroeconomists. However, they are rarely used in practice due to over-parameterization concerns, difficulties in ensuring identification and computational challenges. With the growing interest in multivariate time series models of high dimension, these problems with VARMAs become even more acute, accounting for the dominance of VARs in this field. In this paper, we develop a Bayesian approach for inference in VARMAs which surmounts these problems. It jointly ensures identification and parsimony in the context of an efficient Markov chain Monte Carlo (MCMC) algorithm. We use this approach in a macroeconomic application involving up to twelve dependent variables. We find our algorithm to work successfully and provide insights beyond those provided by VARs.
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This work compares the structural/dynamics features of the wild-type alb-adrenergic receptor (AR) with those of the D142A active mutant and the agonist-bound state. The two active receptor forms were compared in their isolated states as well as in their ability to form homodimers and to recognize the G alpha q beta 1 gamma 2 heterotrimer. The analysis of the isolated structures revealed that, although the mutation- and agonist-induced active states of the alpha 1b-AR are different, they, however, share several structural peculiarities including (a) the release of some constraining interactions found in the wild-type receptor and (b) the opening of a cytosolic crevice formed by the second and third intracellular loops and the cytosolic extensions of helices 5 and 6. Accordingly, also their tendency to form homodimers shows commonalties and differences. In fact, in both the active receptor forms, helix 6 plays a crucial role in mediating homodimerization. However, the homodimeric models result from different interhelical assemblies. On the same line of evidence, in both of the active receptor forms, the cytosolic opened crevice recognizes similar domains on the G protein. However, the docking solutions are differently populated and the receptor-G protein preorientation models suggest that the final complexes should be characterized by different interaction patterns.
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Time varying parameter (TVP) models have enjoyed an increasing popularity in empirical macroeconomics. However, TVP models are parameter-rich and risk over-fitting unless the dimension of the model is small. Motivated by this worry, this paper proposes several Time Varying dimension (TVD) models where the dimension of the model can change over time, allowing for the model to automatically choose a more parsimonious TVP representation, or to switch between different parsimonious representations. Our TVD models all fall in the category of dynamic mixture models. We discuss the properties of these models and present methods for Bayesian inference. An application involving US inflation forecasting illustrates and compares the different TVD models. We find our TVD approaches exhibit better forecasting performance than several standard benchmarks and shrink towards parsimonious specifications.
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L'auteur fait une synthèse des contributions, actuelles ou passées, décrivant la tendance chez un individu à exacerber ses sensations (hyperesthésie), agréables ou douloureuses, y compris les éprouvés émotionnels. Il met l'accent sur l'effet antagoniste ou inhibiteur que les sensations peuvent avoir les unes sur les autres. Puisque l'angoisse implique, elle aussi, une dimension sensorielle, il insiste sur le but paradoxal d'apaisement et donc défensif qui peut motiver la recherche de sensations, en se référant à la notion de « procédé autocalmant » développée par l'école psychosomatique de Paris.¦Ce travail se divise en deux parties consacrées respectivement à l'enfant et à l'adulte, elles-mêmes déclinées sur deux versants, l'un « normal » et l'autre pathologique. Il y est question :¦- des comportements de l'enfant susceptibles d'être produits pour les sensations apaisantes qu'ils procurent : succion, ingestion d'aliments, balancement, masturbation, etc.¦- des auto-agressions dans certains troubles du développement de l'enfant et de l'adolescent¦- de l'hypersensibilité ou émotivité dans les typologies du tempérament ou du caractère proposées dans l'histoire; de la passion également, envisagée comme un embrasement lui aussi potentiellement défensif¦- de deux parmi les troubles de l'adulte qui ont le plus été décrits en termes d'hyperesthésie, à savoir l'hystérie et la manie.¦Il s'agit d'un travail théorique, qui intègre des aspects historiques, et qui peut servir de base à des explorations cliniques ou des recherches plus spécifiques.¦The author presents a summary of past and recent publications describing the disposition in the individual to exacerbate sensations (hyperesthesia), whether pleasurable or painful, including emotional experiences. He emphasizes the possible opposing or inhibiting action these sensations can have between them.¦As anxiety also implies a sensory dimension, the author underlines the paradoxically alleviating, and hence defensive purpose driving the pursuit of sensations, by reference to the notion of self-soothing procedures (procédés auto-calmants), conceptualized by the Paris Psychosomatic School.¦This work is divided into two parts focusing on childhood and adulthood respectively, each in its turn concentrating on both the « normal » and pathological aspects. Topics covered include:¦- behaviours that children may engage in for the soothing effects they produce ; sucking, consumption of food, rocking, masturbation, etc.¦- self-harm in some cases of developmental disorders in children and adolescents¦- hypersensibility and emotivity as described in historical temperament and character types ; passion, also regarded as another defensive excitement.¦- two of the most commonly described disorders of hyperesthesia in adults, namely hysteria and mania.¦This thesis constitutes a research of a theoretical nature. It integrates historical aspects, which can be used as a basis for clinical exploration or further more specific research.
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The autonomous regulatory agency has recently become the ‘appropriate model’ of governance across countries and sectors. The dynamics of this process is captured in our data set, which covers the creation of agencies in 48 countries and 16 sectors since the 1920s. Adopting a diffusion approach to explain this broad process of institutional change, we explore the role of countries and sectors as sources of institutional transfer at different stages of the diffusion process. We demonstrate how the restructuring of national bureaucracies unfolds via four different channels of institutional transfer. Our results challenge theoretical approaches that overemphasize the national dimension in global diffusion and are insensitive to the stages of the diffusion process. Further advance in study of diffusion depends, we assert, on the ability to apply both cross-sectoral and cross-national analysis to the same research design and to incorporate channels of transfer with different causal mechanisms for different stages of the diffusion process.