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Among the almost 1400 landslides triggered by the shocks of the 2016–2017 central Italy seismic sequence, only a limited number, all classifiable as rockslides, involved volumes larger than 1000 m 3. Four of these failures, including the three largest among the documented landslides, were described in terms of structural and geomechanical investigations in a previous paper. In this study, the estimated acceleration time histories at the rockslide sites were evaluated through a 2D simplified numerical model accounting for the attenuation phenomena and for the topographic effect of the rock cliffs from which the slide detached. Instantaneous stability analyses were carried out to obtain insights into the variability of the instantaneous margin of safety along the motion, over the entire spectrum of mechanisms that could be activated. Finally, some general suggestions on the pseudo-static verification method for 3D cases are proposed, which represent useful indications to hazard evaluation at local and regional scales. [ABSTRACT FROM AUTHOR]

Purpose – Tourism systems have been considered more and more in the light of complexity and chaos theories. Most of the work done in this area has highlighted the reasons for and the issues regarding this approach. A steadily growing strand of the recent literature uses the theories to overcome the problems of a reductionist and mechanistic view that is considered unable to provide a full understanding of the structural and dynamic characteristics of tourism systems, and specifically of tourism destinations. This paper seeks to continue this approach and to provide a series of quantitative methods to assess the dynamics of non-linear complex tourism systems. Design/methodology/approach – The time series used in the paper contains data collected from a sample of 23 large (four-star) hotels located in Milan, Italy. For each structure daily data of occupancy, average room rate and RevPAR (revenue per available room) were recorded for the period 2006-2009. The daily distributions of these observations are highly skewed, and therefore the median of the daily values were considered. This results in three series of 1,461 points per type (occupancy, room rate and RevPAR). Findings – The data confirm the complex nature of the destination system and its tendency towards a chaotic state. Additionally, high stability and long memory effects are detected. The outcomes and the implications of this analysis are examined. Research limitations/implications – A comparison of the values obtained leads to the conclusion that the series under study has a detectable level of non-linearity, even if it does not reach the pure chaoticity of the Lorenz attractor. A first conclusion is that, as qualitatively assessed in many similar studies, the tourism destination is a complex system with a tendency to become chaotic. Originality/value – The picture obtained with the analyses conducted can be summarised by saying that the system under study exhibits an unequivocally complex nature. It tends towards a chaotic stage but does so at a slow pace. The stability of the system is quite high: it might be able to resist transient shocks well but, once led in one direction, its long memory characteristics tend to keep it on the resulting path. [ABSTRACT FROM AUTHOR]

This paper contains the lecture notes of the short courses given by one of us (F.Z.) at the summer school Fundamental Problems in Statistical Physics XV , held in Brunico, Italy, in July 2021, and, just before that, at the summer school Glassy Systems and Inter-Disciplinary Applications , held in Cargese, France, in June 2021. The course was a short introductory overview of the dynamics of disordered systems, focused in particular on the equilibrium dynamics (with the associated glass transition), and on the simplest case of off-equilibrium dynamics, namely gradient descent. A few selected topics (and references) are chosen, based on the authors' own taste and competences, and on pedagogical reasons, without aiming at a complete review of the subject. [ABSTRACT FROM AUTHOR]

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We show, for the first time, the explicit form of the nonlinear partial differential equations (PDEs) subject to the correct boundary conditions that have to be satisfied by transport coefficients having a vanishing skew-symmetric piece. We also report, for the first time, the nonlinear PDEs (with the appropriate boundary conditions) for transport coefficients when the thermodynamic system is subject to two thermodynamic forces. Since the proposed PDEs have been derived without neglecting any term present in the dynamical equations (i.e., the energy, mass, and momentum balance equations), we propose them as a good candidate for describing transport in thermodynamic systems also far from equilibrium (e.g., in the turbulent regime). The preliminary test was carried out by analyzing a concrete example where Onsager's relationships manifestly disagree with experience: magnetically confined Tokamak-plasmas. More specifically, we focus our calculations to compute mass and energy transports in Frascati Tokamak Upgrade-plasmas subject to two thermodynamic forces. We show a good agreement between the theoretical predictions and the experimental data. The aim of this study is to apply our approach to the Divertor Tokamak Test Facility, to be built in Italy, and to the International Thermonuclear Experimental Reactor. [ABSTRACT FROM AUTHOR]

Naturally occurring 222Rn is increasingly recognized as a powerful environmental tracer in hydrology. Radon-in-water concentrations can be measured in the field by stripping radon from a water sample into a gas volume and measuring the respective radon-in-gas concentration using a portable radon-in-gas monitor. Alternatively, radon is firstly extracted from the water body by diffusion through a radon exchanger such as polypropylene (PP) tubing and then is measured using a radon-in-gas monitor, connected in closed-loop to the PP membrane. The paper discusses results of field experiments in which the Radon-in-Water Probe (Durridge co.), a 2.2 m long PP tubing, connected to a RAD7 monitor (method A), is used to determine dissolved radon concentration in four water bodies characterised by different water flow velocity and radon concentration. The efficiency of this method is validated by comparison with two established methods, gamma-ray spectrometer + charcoal canister (method B) and RAD7 monitor + Big Bottle RAD H20 accessory (method C). Relative efficiency of method A is directly proportional to water flow velocity, ranging from about 0.50 ± 0.05 at 0.01 m/s to about 0.92 ± 0.08 at 0.57 m/s. A minimum of 2–3 h are needed to collect enough records to asymptotically fit radon-in-gas data and obtain equilibrium radon concentration, which is then converted into radon-in water concentration, considering the temperature-dependency of radon partition coefficient between water and air. Equilibrium condition is reached after about 6–8 h. No correlation was found between relative efficiency and radon concentration. An equation is proposed to correct radon data as a function of water flow velocity, even for poorly moving water bodies. The DURRIDGE Water Probe is useful to monitor radon-in-water levels, without the potential risk of radon loss during water sampling and sample handling. However, it must be pointed out that duplicate or triplicate sampling using other methods similarly permit to evaluate whether radon loss is an issue. • Radon-in-Water Probe set-up is tested to determine dissolved radon concentrations. • Its efficiency is validated against two established and cross-calibrated methods. • Equilibrium radon concentration is reached after 6–8 h. • Relative efficiency depends on water flow velocity and not on radon concentration. • An equation is proposed to estimate dissolved radon, even for poorly moving water. [ABSTRACT FROM AUTHOR]

In many countries settlements take place a fixed number of business days after the transaction (U.S., Japan). In other countries settlements take place periodically on a fixed date when all transactions performed before this date are settled (U.K., France, Italy). In both cases settlement procedures should cause returns not to be identically distributed over all days. The effect is likely to be the largest on markets where all trades are settled only once a month. An empirical investigation of the largest of those markets, the Paris Bourse, demonstrates the importance of the settlement procedure on the distribution of daily returns. [ABSTRACT FROM AUTHOR]

The article discusses the balance of payments adjustment process. The author notes that policy problems generated by unsatisfactory developments in world economic activity have increased due to a number of countries which are in considerable external disequilibrium. The account balance of Organization of Petroleum Exporting Countries (OPEC) is looked at, having stabilized at approximately $35 billion. Imbalances within the Organization for Economic Cooperation and Development (OECD), however, are considerable in spite of the progress made towards better balance achieved by Great Britain and Italy. A table is presented which demonstrates the changes in account balance, liabilities to foreign official agencies, and balances financed by transactions in reserve assets of several industrial countries from 1973 to 1977.

Radionuclide maps of the Molise region were created for the first time using gamma-ray spectrometry analysis of 205 soil samples. The geographical distributions of K, Th and U were within the world average values for soils. K was distributed homogeneously with a slight enhancement along the coastline. The decay chains of U and Th were in secular equilibrium with their daughters, also showing a homogeneous distribution except for localized areas of enhanced concentrations close to the borders with the Lazio and the Campania regions. Concentrations of all three radionuclides were correlated with geological and pedological characteristics of soils. The measured external gamma-dose rate in the air due to naturally occurring radionuclides in the soil, and the dose rate due to cosmic rays were in agreement with values measured in other Mediterranean regions. Increased Cs levels from atmospheric nuclear weapons tests and the Chernobyl fallout were found at sites above 1,000 m a.s.l. [ABSTRACT FROM AUTHOR]

We present experimental phase equilibria carried out on a pantelleritic bulk-rock composition with a peralkalinity index [PI = molar (Na2O + K2O)/Al2O3] = 1·4, which is representative of the most energetic pumice fall eruption of the resurgent post-caldera volcanism on Pantelleria island. For the explored conditions (P = 25–150 MPa; T = 680–800°C; H2Omelt up to 6 wt %; fO2 ≤ NNO, where NNO is nickel–nickel oxide buffer) clinopyroxene is the liquidus phase followed by alkali feldspar and then quartz. The crystallization of amphibole is limited to temperatures below 700°C. Aenigmatite crystallizes near the liquidus for P ≥ 100 MPa. When clinopyroxene is the sole liquidus phase, the coexisting melt is characterized by a decrease in peralkalinity index to 1·2, if compared with the starting material, approaching comendite composition. In contrast, when alkali feldspar joins the liquidus phase assemblage, residual melts become extremely peralkaline (PI = 3·2), with FeO contents in excess of 14 wt %. Comparison of our experiments with natural phase abundances and compositions constrains the depth of the Fastuca pantellerite reservoir to be around 5 ± 1 km (or P = 120 ± 20 MPa) at T = 730 ± 10°C, with H2Omelt around 4 wt %, and fO2 1·5 log unit below NNO. Such conditions correspond to the dominant phase assemblage of feldspar, clinopyroxene and aenigmatite. Amphibole occurrence requires both higher melt water contents and lower temperatures (up to 6·5 wt % at 680°C), and may reflect provenance from a deeper and wetter portion of the tapped reservoir. In contrast, quartz is more probably related to crystallization during magma ascent, which explains the lower melt water content of its melt inclusions. Overall, the results confirm that pantellerites may be both water-rich and reduced magmas. These characteristics imply that any coexisting fluid phase in the reservoir will be dominated by water and hydrogen species, the latter amounting to a few mole per cent. Magma unrest at Pantelleria may thus be heralded by emissions of hydrous and reduced gases (i.e. CO2-poor and H2-rich), if the present-day reservoir is felsic in composition. [ABSTRACT FROM PUBLISHER]

This article investigates the pricing-to-market (PTM) behaviour of Italian exporting firms, using quarterly survey data by sector and by region over the period 1999q1 to 2005q2. A partial equilibrium imperfect competition model provides the structure according to which the orthogonality of structural shocks is derived. Impulse response analysis shows non-negligible reactions of export-domestic price margins to unanticipated changes in cost competitiveness and in foreign and domestic demand levels, even though these effects appear to be of a transitory nature. For the period 1999 to 2001, a typical PTM behaviour emerges, while, during the most recent years favourable foreign demand conditions allowed firms to increase their export-domestic price margins in face of a strong deterioration of their cost competitiveness. Macroeconomic implications of the observed PTM behaviour are also discussed. [ABSTRACT FROM AUTHOR]