Testing for public debt sustainability using a time-scale decomposition analysis

In this paper we estimate the response of primary surplus to lagged debt to test for debt sustainability within the 17 EMU countries by using a factor model. The analysis is split into two stages. In the first stage we retrieve the cyclical and long-run components of primary surplus and debt ratios of each EMU country using a wavelet decomposition for each fiscal covariate, based on the Maximal Overlapping Discrete Wavelet Transform. In the second stage, we use Full Information Maximum Likelihood for a factor decomposition of thecross covariance matrix of the wavelet coefficients of primary deficit and debt to GDP ratios in order to measure the short run and the long run reaction of the primary surplus to (lagged) debt. The empirical evidence shows a positive response of primary surplus to debt within EMU as a whole. Country specific factor decomposition confirms Germany as the one of the most virtuous countries, and, Italy, as the only PIIGS member on a long-run sustainable path for deb

Testing for Contagion: a Time-Scale Decomposition

The aim of the paper is to test for financial contagion by estimating a simultaneous equation model subject to structural breaks. For this purpose, we use the Maximum Overlapping Discrete Wavelet Transform, MODWT, to decompose the covariance matrix of four asset returns on a scale by scale basis. This decomposition will enable us to identify the structural form model and to test for spillover effects between country specific shocks during a crisis period. We distinguish between the case of the structural form model with a single dummy and the one with multiple dummies capturing shifts in the co-movement of asset returns occurring during periods of financial turmoil. The empirical results for four East Asian emerging stock markets show that, once we account for interdependence through an (unobservable) common factor, there is hardly any evidence of contagion during the 1997-1998 financial turbulence

Financial connectedness among European volatility risk premia

In this paper we use the Diebold Yilmaz (2009 and 2012) methodology to estimate the contribution and the vulnerability to systemic risk of volatility risk premia for five European stock markets: France, Germany, UK, Switzerland and the Netherlands. The volatility risk premium, which is a proxy of risk aversion, is measured by the difference between the implied volatility and expected realized volatility of the stock market for next month. While Diebold and Yilmaz focus is on the forecast error variance decomposition of stock returns or range based volatilities employing a stationary VAR in levels, we account for the (locally) long memory stationary properties of the levels of volatility risk premia series. Therefore, we estimate and invert a Fractionally Integrated VAR model to compute the cross forecast error variance shares necessary to obtain the index of total and directional connectedness

Volatility co-movements: a time scale decomposition analysis

In this paper we investigate short-run co-movements before and after the Lehman Brothers\u2019 collapse among the volatility series of US and a number of European countries. The series under investigation (implied and realized volatility) exhibit long-memory and, in order to avoid miss-specification errors related to the parameterization of a long memory multivariate model, we rely on wavelet analysis. More specifically, we retrieve the time series of wavelet coefficients for each volatility series for high frequency scales, using the Maximal Overlapping Discrete Wavelet transform and we apply Maximum Likelihood for a factor decomposition of the short-run covariance matrix. The empirical evidence shows an increased interdependence in the post-break period and points at an increasing (decreasing) role of the common shock underlying the dynamics of the implied (realized) volatility series, once we move from the 2-4 days investment time horizon to the 8-16 days. Moreover, there is evidence of contagion from the US to Europe immediately after the Lehman Brothers\u2019 collapse, only for realized volatilities over an investment time horizon between 8 and 16 days

Studies for the Conservation and Valorisation of the Archaeological Rock Heritage of Calascibetta in Sicily, Italy

Abstract. The rock settlement of Vallone Canalotto, which stands in the valleys surrounding the town of Calascibetta – about three kilometres north from Enna, Sicily, Italy – testify to a widespread population of the area from prehistoric times up to the Middle Ages, probably linked to the agricultural and pastoral exploitation of its fertile land. This valuable heritage, dug into very soft limestone banks, is now threatened by significant erosion and disruption phenomena, which, in the absence of adequate safeguarding and maintenance actions, will lead to a progressive loss of material and the consequent collapse of some portions, making the documentable traces more and more paltry. The archaeological complex demonstrates the continuity of the funerary use from the remotest ages to the early Christian era, as testified by the excavation of rupestrian columbaria. In the early medieval period, small rural communities used the hypogeal structures for residential and religious purposes. In the present work, integrated procedures have been put in place for the 3D documentation of these artefacts, whose effectiveness has already been tested by the same team in other Sicilian rock sites. The research aims at the knowledge and cataloguing of places, which are important for the Island's history but to date only marginally explored. It intends to stimulate and plan adequate conservation and enhancement activities. To improve the attendance of the sites, design proposals have been developed to guarantee greater accessibility to the archaeological areas and their understanding by visitors

Curcumin as scaffold for drug discovery against neurodegenerative diseases

Neurodegenerative diseases (NDs) are one of major public health problems and their impact is continuously growing. Curcumin has been proposed for the treatment of several of these pathologies, such as Alzheimer’s disease (AD) and Parkinson’s disease (PD) due to the ability of this molecule to reduce inflammation and aggregation of involved proteins. Nevertheless, the poor metabolic stability and bioavailability of curcumin reduce the possibilities of its practical use. For these reasons, many curcumin derivatives were synthetized in order to overcome some limitations. In this review will be highlighted recent results on modification of curcumin scaffold in the search of new effective therapeutic agents against NDs, with particular emphasis on AD

Note tassonomiche e biosistematiche su Anthemis aeolica (Asteraceae).

Sono riportati i risultati relativi alla caratterizzazione morfologica, distribuzione attuale , ecologia e correlazioni sistematiche della specie endemica Anthemis aeolic

Seroprevalence of Toxoplasma gondii in swine slaughtered in Sicily

Several studies showed that the consumption of raw or undercooked meat contaming Toxoplasma gondii tissue cysts from infected animals is one of the most important sources of human toxoplasmosis. Foods of animal origin most frequently contaminated are pork and small ruminants\u27 meat. In order to investigate the seroprevalence of Toxoplasmosis in Sicilian pig farms, 1063 swine sera were collected dunng the slaughtering from locally born and bred ammals and 1312 from imported ones (from France and Spain). The local animals came from 154 farms distributed along Sicily, representing pigs of all ages: the others came from lairages

Curcumin affects HSP60 folding activity and levels in neuroblastoma cells

The fundamental challenge in fighting cancer is the development of protective agents able to interfere with the classical pathways of malignant transformation, such as extracellular matrix remodeling, epithelial\u2013mesenchymal transition and, alteration of protein homeostasis. In the tumors of the brain, proteotoxic stress represents one of the main triggering agents for cell transformation. Curcumin is a natural compound with anti-inflammatory and anti-cancer properties with promising potential for the development of therapeutic drugs for the treatment of cancer as well as neurodegenerative diseases. Among the mediators of cancer development, HSP60 is a key factor for the maintenance of protein homeostasis and cell survival. High HSP60 levels were correlated, in particular, with cancer development and progression, and for this reason, we investigated the ability of curcumin to affect HSP60 expression, localization, and post-translational modifications using a neuroblastoma cell line. We have also looked at the ability of curcumin to interfere with the HSP60/HSP10 folding machinery. The cells were treated with 6, 12.5, and 25 \ub5M of curcumin for 24 h, and the flow cytometry analysis showed that the compound induced apoptosis in a dose-dependent manner with a higher percentage of apoptotic cells at 25 \ub5M. This dose of curcumin-induced a decrease in HSP60 protein levels and an upregulation of HSP60 mRNA expression. Moreover, 25 \ub5M of curcumin reduced HSP60 ubiquitination and nitration, and the chaperonin levels were higher in the culture media compared with the untreated cells. Furthermore, curcumin at the same dose was able to favor HSP60 folding activity. The reduction of HSP60 levels, together with the increase in its folding activity and the secretion in the media led to the supposition that curcumin might interfere with cancer progression with a protective mechanism involving the chaperonin