Current account determinants and external sustainability in periods of structural change

The aim of this paper is to study the main macroeconomic, financial and structural characteristics that affected current account developments in Greece over the period 1960-2007 and link these to the issue of external sustainability. Concerns over Greece’s external sustainability have emerged since 1999 when the current account deficit widened substantially and exhibited high persistence. The empirical model used, which theoretically rests on the intertemporal approach, treats the current account as the gap between domestic saving and investment. We examine the behaviour of the current account in the long run and the short run using co-integration analysis and a variety of econometric tests to account for the effect of significant structural changes in the period under review. We find that a stable equilibrium current account model can be derived if the ratio of private sector financing to GDP, as a proxy for financial liberalization, is included in the specification. Policy options to restore the country’s external sustainability are explored by performing a simulation exercise based on the estimated equilibrium model.Current account model; external sustainability

Current account determinants and external sustainability in periods of structural change

The aim of this paper is to study the main macroeconomic, financial and structural factors that shaped current account developments in Greece over the period from 1960 to 2007 and discuss these developments in relation to the issue of external sustainability. Concerns over Greece’s external sustainability have emerged since 1999 when the current account deficit widened substantially and exhibited high persistence. The empirical model used, which theoretically rests on the intertemporal approach, treats the current account as the gap between domestic saving and investment. We examine the behaviour of the current account in the long run and the short run using co-integration analysis and a variety of econometric tests to account for the effect of significant structural changes in the period under review. We find that a stable equilibrium current account model can be derived if the ratio of private sector financing to GDP, as a proxy for financial liberalisation, is included in the specification. Policy options to restore the country’s external sustainability are explored based on the estimated equilibrium model. JEL Classification: F30, F32Current account model, external sustainability

Hadrons in Dense Resonance-Matter: A Chiral SU(3) Approach

A nonlinear chiral SU(3) approach including the spin 3/2 decuplet is developed to describe dense matter. The coupling constants of the baryon resonances to the scalar mesons are determined from the decuplet vacuum masses and SU(3) symmetry relations. Different methods of mass generation show significant differences in the properties of the spin-3/2 particles and in the nuclear equation of state.Comment: 28 pages, 9 figure

Service Orientation and the Smart Grid state and trends

The energy market is undergoing major changes, the most notable of which is the transition from a hierarchical closed system toward a more open one highly based on a “smart” information-rich infrastructure. This transition calls for new information and communication technologies infrastructures and standards to support it. In this paper, we review the current state of affairs and the actual technologies with respect to such transition. Additionally, we highlight the contact points between the needs of the future grid and the advantages brought by service-oriented architectures.

Rotating Neutron Stars in a Chiral SU(3) Model

We study the properties of rotating neutron stars within a generalized chiral SU(3)-flavor model. The influence of the rotation on the inner structure and the hyperon matter content of the star is discussed. We calculate the Kepler frequency and moments of inertia of the neutron star sequences. An estimate for the braking index of the associated pulsars is given.Comment: 14 pages, 9 figure

Biophysically motivated efficient estimation of the spatially isotropic R*2 component from a single gradient‐recalled echo measurement

Purpose To propose and validate an efficient method, based on a biophysically motivated signal model, for removing the orientation‐dependent part of R*2 using a single gradient‐recalled echo (GRE) measurement. Methods The proposed method utilized a temporal second‐order approximation of the hollow‐cylinder‐fiber model, in which the parameter describing the linear signal decay corresponded to the orientation‐independent part of R*2. The estimated parameters were compared to the classical, mono‐exponential decay model for R*2 in a sample of an ex vivo human optic chiasm (OC). The OC was measured at 16 distinct orientations relative to the external magnetic field using GRE at 7T. To show that the proposed signal model can remove the orientation dependence of R*2, it was compared to the established phenomenological method for separating R*2 into orientation‐dependent and ‐independent parts. Results Using the phenomenological method on the classical signal model, the well‐known separation of R*2 into orientation‐dependent and ‐independent parts was verified. For the proposed model, no significant orientation dependence in the linear signal decay parameter was observed. Conclusions Since the proposed second‐order model features orientation‐dependent and ‐independent components at distinct temporal orders, it can be used to remove the orientation dependence of R*2 using only a single GRE measurement

The Impact of Aortic Occlusion Balloon on Mortality After Endovascular Repair of Ruptured Abdominal Aortic Aneurysms: A Meta-analysis and Meta-regression Analysis

INTRODUCTION:We aimed to investigate whether the use of aortic occlusion balloon (AOB) has an impact on mortality of patients undergoing endovascular repair of ruptured abdominal aortic aneurysms (RAAAs).METHODS:A meta-analysis of the English-language literature was undertaken through February 2013. Articles reporting data on outcome after endovascular repair of RAAAs were identified and information regarding the use of AOB was sought.RESULTS:Included in this meta-analysis were 39 eligible studies reporting 1277 patients. The pooled perioperative mortality was 21.6% (95% CI 18.1-25.1%). There was significant within-study heterogeneity (I(2) 50.2%, P < 0.001). A total of 200 patients required AOB with an estimated pooled proportion of 14.1% (8.9-19.3%). Individual random-effects meta-regression investigating the effect of AOB and other risk factors on mortality revealed a significant linear association of hemodynamic instability, bifurcated endograft approach, and primary conversion to open repair with mortality and a nonlinear (second degree polynomial) association of AOB with mortality. On multivariable meta-regression models, both hemodynamic instability and AOB were found to be statistically significant, independent predictors of mortality. In particular, there was a statistically significant negative correlation between AOB and mortality and a positive effect of hemodynamic instability on mortality. In practical terms, mortality was significantly higher in studies with a higher proportion of hemodynamically unstable patients and lower in studies with a higher rate of AOB use.CONCLUSION:This study provides meta-analytical evidence that the use of an AOB in unstable RAAA patients undergoing endovascular repair may improve the results

Kaon effective mass and energy from a novel chiral SU(3)-symmetric Lagrangian

A new chiral SU(3) Lagrangian is proposed to describe the properties of kaons and antikaons in the nuclear medium, the ground state of dense matter and the kaon-nuclear interactions consistently. The saturation properties of nuclear matter are reproduced as well as the results of the Dirac-Br\"{u}ckner theory. Our numerical results show that the kaon effective mass might be changed only moderately in the nuclear medium due to the highly non-linear density effects. After taking into account the coupling between the omega meson and the kaon, we obtain similar results for the effective kaon and antikaon energies as calculated in the one-boson-exchange model while in our model the parameters of the kaon-nuclear interactions are constrained by the SU(3) chiral symmetry.Comment: 13 pages, Latex, 3 PostScript figures included; replaced by the revised version, to appear in Phys. Rev.

DIAGNOSTIC REVIEW OF A BLACKOUT IN RHODES

U radu se daje tehnička analiza jednog incidenta koji se dogodio 21. ožujka 2007. godine u 00:50 sati u noći i doveo do dvosatnog potpunog raspada elektroenergetskog sustava na otoku Rodosu. Analiza događanja temelji se na registriranim operativnim podacima kao i nalazima na terenu. Izvršena je tehnička analiza smetnji kako bi se utvrdili vjerojatni uzroci i čimbenici koji su pridonijeli pojavi smetnji. S obzirom da se radi o izoliranom sustavu koji je osobito je osjetljiv na poremećaje, ispitane su uloge zaštite sustava kao i kolebanja proizvodnje vjetroelektrana tijekom incidenta. Izvučeni su zaključci od praktičnog značenja i dane su preporuke korektivnih mjera koje valja provesti kako bi se u budućnosti spriječile takve smetnje.A technical review of an incident on March 21, 2007 that began at 00:50 a.m. and led to a two-hour blackout of the island of Rhodes electric power system is presented with the complete sequence, including all the relevant registered operational data as well as the on-site field findings. A technical analysis of the disturbance was performed to determine the probable causes and factors that contributed to the duration of the disturbance. Since the system is an isolated one, it is particularly vulnerable to perturbations. The roles of system protection and wind power generation during the incident are examined. Conclusions of practical importance are drawn, including recommendations for corrective measures to be implemented for preventing disturbances of this kind from reoccurring in the future