938 resultados para UNSTABLE DIMENSION VARIABILITY
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Recent years have seen a striking proliferation of the term ‘global’ in public and political discourse. The popularity of the term is a manifestation of the fact that there is a widespread notion that contemporary social reality is ‘global’. The acknowledgment of this notion has important political implications and raises questions about the role played by the idea of the ‘global’ in policy making. These questions, in turn, expose even more fundamental issues about whether the term ‘global’ indicates a difference in kind, even an ontological shift, and, if so, how to approach it. This paper argues that the notion of ‘global’, in other words the ‘global dimension’, is a significant aspect of contemporary politics that needs to be investigated. The paper argues that in the globalization discourse of International Studies ‘global’ is ‘naturalized’, which means that it is taken for granted and assumed to be self-evident. The term ‘global’ is used mainly in a descriptive way and subsumed under the rubric of ‘globalization’. ‘Global’ tends to be equated with transnational and/or world-wide; hence, it addresses quantitative differences in degree but not (alleged) differences in kind. In order to advance our understanding of contemporary politics, ‘global’ needs to be taken seriously. This means, firstly, to understand and to conceptualize ‘global’ as a social category; and, secondly, to uncover ‘global’ as a ‘naturalized’ concept in the Political and International Studies strand of the globalization discourse in order to rescue it for innovative new approaches in the investigation of contemporary politics. In order to do so, the paper suggests adopting a strong linguistic approach starting with the analysis of the word ‘global’. Based on insights from post-structuralism as well as cognitive and general constructivist perspectives it argues that a frame-based corpus linguistic analysis offers the possibility of investigating the collective/social meaning(s) of global in order to operationalize them for the analysis of the ‘global dimension’ of contemporary politics.
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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 report experiments designed to test between Nash equilibria that are stable and unstable under learning. The “TASP” (Time Average of the Shapley Polygon) gives a precise prediction about what happens when there is divergence from equilibrium under fictitious play like learning processes. We use two 4 x 4 games each with a unique mixed Nash equilibrium; one is stable and one is unstable under learning. Both games are versions of Rock-Paper-Scissors with the addition of a fourth strategy, Dumb. Nash equilibrium places a weight of 1/2 on Dumb in both games, but the TASP places no weight on Dumb when the equilibrium is unstable. We also vary the level of monetary payoffs with higher payoffs predicted to increase instability. We find that the high payoff unstable treatment differs from the others. Frequency of Dumb is lower and play is further from Nash than in the other treatments. That is, we find support for the comparative statics prediction of learning theory, although the frequency of Dumb is substantially greater than zero in the unstable treatments.
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PURPOSE: To determine prognostic factors and evaluate outcomes of transcatheter arterial embolization in severely injured patients in hemodynamically unstable condition with multicompartmental bleeding.¦MATERIALS AND METHODS: Between June 2000 and May 2008, 36 consecutive patients treated with transcatheter arterial embolization for major retroperitoneal bleeding associated with at least one additional source of bleeding were retrospectively reviewed. Mean Injury Severity Score (ISS) was 49.4 ± 15.8. Univariate and multivariate analyses were performed to identify parameters associated with failure of embolization, need for additional surgery to control bleeding, and fatal outcome at 30 d.¦RESULTS: Embolization was technically successful in 35 of 36 patients (97.2%) and resulted in immediate and sustained (> 24 h) hemodynamic improvement in 29 (80.5%). Additional hemostatic surgery was necessary after embolization in six patients (16.6%). Fifteen patients (41.6%) died within 30 d. Failure to restore hemodynamic stability was correlated with the rate of administration of packed red blood cells (P = .014), rate of administration of fresh frozen plasma (FFP; P = .031), and systolic blood pressure (SBP) immediately before embolization (P = .002). The need for additional surgery was correlated with FFP administration rate before embolization (P = .0002) and hemodynamic success (P = .003). Death was correlated with Glasgow Coma Scale score at admission (P = .001), ISS (P = .014), New Injury Severity Score (P = .016), number of injured sites (P = .012), SBP before embolization (P = .042), need for vasopressive drugs before embolization (P = .037), and hemodynamic success (P = .0004).¦CONCLUSIONS: In patients in hemodynamically unstable condition, transcatheter arterial embolization effectively controls bleeding and improves hemodynamic stability. Immediate survival is related to hemodynamic condition before embolization, and 30-d mortality is mainly related to associated brain trauma.
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We study the screening problem that arises in a framework where, initially, the agent is privately informed about both the expected production cost and the cost variability and, at a later stage, he learns privately the cost realization. The speci c set of relevant incentive constraints, and so the characteristics of the optimal mechanism, depend nely upon the curvature of the principal s marginal surplus function as well as the relative importance of the two initial information problems. Pooling of production levels is optimally induced with respect to the cost variability when the principal's knowledge imperfection about the latter is sufficiently less important than that about the expected cost.
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INTRODUCTION: Therapeutic hypothermia (TH) is often used to treat out-of-hospital cardiac arrest (OHCA) patients who also often simultaneously receive insulin for stress-induced hyperglycaemia. However, the impact of TH on systemic metabolism and insulin resistance in critical illness is unknown. This study analyses the impact of TH on metabolism, including the evolution of insulin sensitivity (SI) and its variability, in patients with coma after OHCA. METHODS: This study uses a clinically validated, model-based measure of SI. Insulin sensitivity was identified hourly using retrospective data from 200 post-cardiac arrest patients (8,522 hours) treated with TH, shortly after admission to the intensive care unit (ICU). Blood glucose and body temperature readings were taken every one to two hours. Data were divided into three periods: 1) cool (T <35°C); 2) an idle period of two hours as normothermia was re-established; and 3) warm (T >37°C). A maximum of 24 hours each for the cool and warm periods was considered. The impact of each condition on SI is analysed per cohort and per patient for both level and hour-to-hour variability, between periods and in six-hour blocks. RESULTS: Cohort and per-patient median SI levels increase consistently by 35% to 70% and 26% to 59% (P <0.001) respectively from cool to warm. Conversely, cohort and per-patient SI variability decreased by 11.1% to 33.6% (P <0.001) for the first 12 hours of treatment. However, SI variability increases between the 18th and 30th hours over the cool to warm transition, before continuing to decrease afterward. CONCLUSIONS: OCHA patients treated with TH have significantly lower and more variable SI during the cool period, compared to the later warm period. As treatment continues, SI level rises, and variability decreases consistently except for a large, significant increase during the cool to warm transition. These results demonstrate increased resistance to insulin during mild induced hypothermia. Our study might have important implications for glycaemic control during targeted temperature management.
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Purpose: Revolutionary endovascular treatments are on the verge of being available for management of ascending aortic diseases. Morphometric measurements of the ascending aorta have already been done with ECG-gated MDCT to help such therapeutic development. However the reliability of these measurements remains unknown. The objective of this work was to compare the intraobserver and interobserver variability of CAD (computer aided diagnosis) versus manual measurements in the ascending aorta. Methods and materials: Twenty-six consecutive patients referred for ECG-gated CT thoracic angiography (64-row CT scanner) were evaluated. Measurements of the maximum and minimum ascending aorta diameters at mid-distance between the brachiocephalic artery and the aortic valve were obtained automatically with a commercially available CAD and manually by two observers separately. Both observers repeated the measurements during a different session at least one month after the first measurements. Intraclass coefficients as well the Bland and Altman method were used for comparison between measurements. Two-paired t-test was used to determine the significance of intraobserver and interobserver differences (alpha = 0.05). Results: There is a significant difference between CAD and manual measurements in the maximum diameter (p = 0.004) for the first observer, whereas the difference was significant for minimum diameter between the second observer and the CAD (p <0.001). Interobserver variability showed a weak agreement when measurements were done manually. Intraobserver variability was lower with the CAD compared to the manual measurements (limits of variability: from -0.7 to 0.9 mm for the former and from -1.2 to 1.3 mm for the latter). Conclusion: In order to improve reproductibility of measurements whenever needed, pre- and post-therapeutic management of the ascending aorta may benefit from follow-up done by a unique observer with the help of CAD.
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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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This thesis argues that insofar as we want to account for the normative dimension of social life, we must be careful to avoid construing that normative dimension in such a way as to exclude that which the second-person perspective reveals is important to social life and our ability to participate in it.¦The second-person perspective reveals that social life ought to be understood as a mix or balance of the regular and the irregular, where, in addition, those one interacts with are always to some extent experienced as other in a way that is neither immediately, nor perhaps ultimately, understandable. For persons to be able to participate in social life, conceived of in this way, they must have abilities that allow them to be, to some extent, hesitant and tentative in their relations with others, and thus tolerant of ambiguity, uncertainty and unpredictability, and responsive to and capable of learning from the otherness of others in the course of interacting with them.¦Incorporating the second-person perspective means we have to make some changes to the way we think about the normative in general, and the normative dimension of social life in particular. It does not mean giving up on the distinction between the normative and the regular - that continues to be fundamentally important but it does mean not excluding, as part of social life and as worthy of explanation, all that which is irregular. A radical way of putting it would be to say that there must be a sense in which the irregular is part of the normative. A less radical way, and the way adopted by this thesis, is to say that any account of the normative dimension of social life must not be such as to exclude the importance of irregularity from social life. This will mean 1) not characterising conventions, norms and rules as determinants of appropriateness and inappropriateness; 2) not thinking of them as necessary; 3) not thinking of them as necessarily governing minds; and 4) not thinking of them as necessarily shared.¦-¦L'argument principal de la thèse est que, pour rendre compte de la dimension normative de la vie sociale, il faut veiller à ne pas exclure la perspective de la deuxième personne - une perspective importante pour comprendre la vie sociale et la capacité requise pour y participer.¦Cette perspective nous permet d'imaginer la vie sociale comme un mélange ou un équilibre entre le régulier et l'irrégulier, l'interaction entre des individus pouvant être appréhendée comme l'expérience de chaque personne avec «l'autre» d'une manière qui n'est pas immédiatement compréhensible, et qui ne peut pas, peut-être, être ultimement comprise. Pour participer à la vie sociale, l'on doit avoir la capacité de rester hésitant et «réactif» dans ses relations avec les autres, de rester ouvert à leur altérité et de tolérer l'ambiguïté, l'incertitude et l'imprévisibilité des interactions sociales.¦Adopter une perspective «à la deuxième personne» conduit à une autre manière de penser la normativité en général, et la dimension normative de la vie sociale en particulier. Cela ne veut pas dire qu'il faut abandonner la distinction entre le normatif et le régulier - une distinction qui garde une importance fondamentale - mais qu'il faut reconnaître l'irrégulier comme faisant partie de la vie sociale et comme étant digne, en tant que tel, d'être expliqué. Une conception radicale pourrait même concevoir l'irrégulier comme faisant partie intégrante de la normativité. Une approche moins radicale, qui est celle adoptée dans cette thèse, est de dire que tout compte-rendu de la dimension normative de la vie sociale doit prendre en considération l'importance de l'irrégularité dans la vie sociale. Une telle approche implique que les conventions, normes et règles (1) ne déterminent pas ce qui est approprié ou inapproprié; (2) ne sont pas toujours nécessaires ; (3) ne gouvernent pas le fonctionnement de l'esprit ; et (4) ne sont pas nécessairement partagées.
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