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Background: Severe hypoglycemia is defined as having low blood glucose levels that requires assistance from another person to treat. Severe hypoglycemia is classed as a diabetic emergency and is a complication that can occur in people with diabetes that take insulin and certain anti-diabetic drugs. The aim of our study was to evaluate the risk factors associated with hospitalization. Methods: The study was retrospectively conducted on the clinical records of adults with severe hypoglycemia who were admitted consecutively to the Emergency Department (ED) of the Carlo Poma Hospital from January 2021 to December 2021. Results: Overall, 50 patients were identified and most of these were elderly and had multiple comorbidities. They were treated with oral hypoglycemic drugs such as sulfonylureas or glinides (42%), insulin (46%) or both (6%). Hospitalization rates and in-hospital deaths occurred in 62% and in 4% of patients, respectively. There is a greater risk of hospitalization (15%) in favor of the group of patients aged ≥ 80 years compared to that with patients aged < 80 years. Conclusions: Severe hypoglycemia increases the risk of hospitalization particulary in elderly diabetic patients. Special care should be taken when prescribing anti-diabetic drugs in elderly patients, in accordance with recent guidelines, in order to avoid episodes of severe hypoglycemia that can lead to hospitalization.

The building of the Apennine belt slowed down or ceased around the Early Pleistocene. Since then, the belt has undergone strong uplift and considerable distortion. This change, from belt-normal to belt-parallel shortening, has been determined by the fact that the continental Adriatic domain (Adria) was almost completely surrounded by buoyant orogenic structures. In that context, the mobility of Adria underwent a considerable reduction, whereas uplift and deformation of its southern part was strongly emphasized as an effect of the convergence of the confining plates. Around the middle Pleistocene, the deformation pattern in the peri-Adriatic zones changed again, in response to acceleration of Adria. The outer (Adriatic) sector of the Apennine belt underwent belt-parallel shortening, accommodated by uplift and outward escape of upper crustal wedges. The separation between the extruding wedges and the almost stable inner belt has generated a series of extensional or transtensional fault systems along the axial part of the Apennines, which now correspond to the main seismogenic sources. The spatio-temporal distribution of major tectonic events in the study area can plausibly be explained as an effect of the least-action principle. Thematic collection: This article is part of the ‘Apennines and Tyrrhenian system’ collection available at: https://www.lyellcollection.org/cc/the-apennines-tyrrhenian-system

The strongest documented seismic disaster ever occurred in the Po Plain area (January 3, 1117, M = 6.5) involved significant damage over a large zone. The genetic mechanism of such an event, most probably caused by more than one earthquake, is still an object of debate. Above all, the sources so far proposed cannot account for significant features of the observed macroseismic field. In this work, we suggest that the damage in the Verona zone was caused by the activation of a fault in the Lessini tectonic district, while damage in the central Po Plain may be related to a thrust fault located beneath the Giudicarie belt. The effects felt in northern Tuscany might derive from the seismic activation of the presumed SW-ward buried prolongation of the Giudicarie fault. The presence of such transpressional lithospheric discontinuity in the Adriatic domain since the upper Miocene and its reactivation (Pliocene-Pleistocene) as a thrust zone is mainly suggested by an accurate analysis of the observed deformation pattern in the central Mediterranean region. The proposed Giudicarie source may also help to explain the damage observed in the central Po Plain on December 25, 1222, which is not compatible with the seismic sources so far proposed.

The observed deformation pattern in the central-western Mediterranean area, in particular the development of the Northern, Central and Southern Tyrrhenian basins in three well distinct phases, can hardly be explained as an effect of the gravitational sinking of subducted lithosphere, a hypothesis often advanced in literature. A more plausible and coherent explanation of the spatio-temporal distribution of major tectonic events in the study area can instead be achieved by supposing that tectonic activity has mainly been driven by the convergence of Africa and Eurasia and the roughly westward displacement of the Anatolian-Aegean-Pelagonian belt. The development of Arc-Trench-Back Arc systems is interpreted as an effect of extrusion processes, that in some constricted contexts have represented the most convenient shortening process for accommodating plate convergence.

The recognition of the seismic zones most prone to next major earthquakes in Italy would considerably help the choice of the most efficient prevention plan. This work describes an attempt to gain reliable information about that problem by exploiting the knowledge about the short-term development of the ongoing tectonic processes in the study area and its influence on the spatio-temporal distribution of major shocks. In the periAdriatic zones, such distribution is connected with the progressive northward displacement of the Adria plate, that is controlled by the progressive activation of the decoupling fault systems in the surrounding belts (Dinarides, Apennines and Eastern Southern Alps). The reliability of this hypothesis is evaluated by analysing the seismic histories of the periAdriatic zones. The regularity patterns that are tentatively recognised in such histories are used to identify the most probable location of next major shocks. Further insights into the present seismic hazard in the Southern Apennines and Calabria are tentatively inferred from tectonic connections between these regions and other periAdriatic zones, suggested by the seismic histories in the last 2–4 centuries and the geodynamic/tectonic context in the central Mediterranean area.

The Tuscany–Romagna–Marche–Umbria Apennines host major seismic zones that have generated several strong earthquakes. We argue that such activity is an effect of the relative motion between the outermost sector of the Romagna–Marche–Umbria units and the surrounding zones. This interpretation is consistent with the pattern of post-early Pleistocene deformation and the present velocity field, inferred from geodetic observations. The last evidence, being derived by a fairly dense network of permanent GPS stations, allows a good definition of the outer Apennine sector which is characterized by a significantly higher velocity (4–6 mm/y, roughly NE ward) with respect to the inner belt (1–2 mm/y, roughly NNW ward). The fact that the main seismic zones are just located along the inner and outer boundaries of the extruding wedge is compatible with the proposed seismogenetic mechanism. Taking into account the tectonic setting in the Apennine belt and the possible effects, in terms of post seismic deformation, of the recent (since 1930) seismicity distribution in that zone, an attempt is made at recognizing which fault systems in the northern Apennines may be most prone to next major shocks (M > 5.5).

In previous papers, we have argued that a close connection may exist between the discontinuous northward displacement of the Adria plate and the spatio-temporal distribution of major earthquakes in the periAdriatic regions [1]-[3]. In particular, five seismic sequences are tentatively recognized in the post 1400 A.D. seismic history, each characterized by a progressive migration of major shocks along the eastern (Hellenides, Dinarides), western (Apennines) and northern (Eastern Southern Alps) boundaries of Adria. In this work, we describe an attempt at gaining insights into the short-term evolution of the strain field that underlies the migration of seismicity in the Apennine belt. The results of this study suggest that seismicity in the study area is mainly conditioned by the fact that the outer (Adriatic) sector of the Apennine belt, driven by the Adria plate, is moving faster than the inner (Tyrrhenian) belt. This kinematics is consistent with the observed Pleistocene deformation pattern and the velocity field inferred by GPS data. The spatio-temporal distribution of major shocks during the last still ongoing seismic sequence (post 1930) suggests that at present the probability of next major shocks is highest in the Northern Apennines. Within this area, we suggest that seismic hazard is higher in the zones located around the outer sector of the Romagna-Marche-Umbria units (RMU), since that wedge is undergoing an accelerated relative motion with respect to the inner Apennine belt. This hypothesis may also account for the pattern of background seismicity in the Northern Apennines. This last activity might indicate that the Upper Tiber Valley fault system is the most resisted boundary sector of the RMU mobile wedge, implying an higher probability of major earthquakes.

An effective mitigation of seismic risk in Italy can hardly be obtained without a tentative recognition of few priority zones, where the limited resources available in the short term can be concentrated. A reliable recognition of the zones where the probability of major earthquakes is highest must be carried out by a deterministic approach, exploiting the profound knowledge acquired about the present seismotectonic context in the zones involved. Some years ago, this kind of procedure led us to identify the central-northern Apennines (i.e. the zone hit by the recent major earthquakes, 2016 and 2017) as the Italian area most prone to next strong shocks. The reliability of the methodology here proposed is also supported by the fact that the implications of the adopted tectonic setting can provide plausible and coherent explanations for the spatio-temporal distribution of major earthquakes in the central Mediterranean area in the last six centuries.

It is argued that in some zones of the Northern Apennines, in particular the Rimini-Ancona thrust system, the Romagna Apennines and the Alta Valtiberina trough, the probability of major earthquakes is now higher than in other Apennine zones. This hypothesis is suggested by the comparison of the present short-term kinematics of the Romagna-Marche-Umbria wedge in the Northern Apennines, deduced by the distribution of major shocks in the last tens of years, with the previous repeated behavior of the same wedge, evidenced by the distribution of major earthquakes in the last seven centuries. The seismotectonics of the Apennine region here considered is closely connected with the larger context that involves the progressive migration (from south to north) of seismicity along the peri-Adriatic zones. The information provided by this study can be used to better manage the resources for prevention in Italy.

The mitigation of seismic risk in Italy could be considerably helped by the recognition of the seismic zones most prone to next strong earthquake. An attempt at achieving such information has been made by considering the present knowledge about the tectonic setting in the study area and its possible connection with the spatio-temporal distribution of major historical earthquakes. The results of such investigation suggest that at present the probability of major socks is highest in the Northern Apennines.

It is argued that the complex tectonic pattern observed in the study area can plausibly be explained as an effect of the kinematics of the Iberia and Adria blocks, induced by the NNE ward motion of Africa and the roughly westward motion of the Anatolian-Aegean system with respect to Eurasia. These boundary conditions cause the constrictional regime which is responsible for the observed shortening processes in the Padanian region and Western Alps. The proposed dynamic context can plausibly account for the peculiar distribution of major seismic sources, located in the northern Apennines, the Giudicarie fault system, the offshore of the western Ligurian coast and the Swiss Alps. The observed tectonic pattern in Western Europe and the study area can hardly be reconciled with the implications of the roughly NWward convergence between Africa and Eurasia proposed by global kinematic models, whereas it is compatible with the alternative Africa-Eurasia kinematics and plate mosaic proposed by [1].

We argue that seismotectonic activity in the Central Mediterranean area and the Aegean–Balkan zone is driven by the NNE-ward motion of Africa and westward motion of Anatolia with respect to Eurasia. These boundary conditions can plausibly and coherently account for E–W shortening and roughly S–N extension in the Aegean domain, thrusting and uplift at the boundary between the Aegean–Balkan system and the Adriatic/Ionian domain (Hellenic trench, Cephalonia fault, Epirus, Albanides and Southern Dinarides), the kinematics of the Adria plate (a large block encompassing the Adriatic continental domain, the northern Ionian zone and Hyblean-Adventure block) and consequently, the complex pattern of deformation recognized at its boundaries. Furthermore, the fact that in our scheme Adria moves almost in connection with Africa is consistent with the lack of an active decoupling zone between Adria and Africa, an evidence that can hardly be reconciled with the kinematics so far proposed for these two plates. The reasons why we adopt an Africa–Eurasia relative motion different from that implied by the popular NUVEL-1 global solution are discussed in detail. Finally, we make some considerations about the possible implications of the presently available geodetic data on the long-term plate kinematics.

The analysis of geodetic observations carried out by 478 continuous GPS stations in the Italian region since 2001 has allowed a fairly good definition of the ongoing horizontal velocity field with respect to Eurasia. It is argued that such evidence can provide important insights into the geodynamic context in the central Mediterranean area. Numerous velocity vectors in the Apulia zone coherently indicate that the southern Adriatic domain is moving roughly NE ward. Since no significant decoupling zone between this domain and Nubia has so far been recognized, one could expect that the kinematics of these two plates is compatible. However, this condition is not fulfilled if the Nubia-Eurasia relative motion is taken from the global kinematic models, either deduced by long-term evidence [1] or short-term geodetic data [2] [3]. This problem is considerably reduced if the alternative Nubia-Eurasia rotation pole suggested by [4] is taken into account. This choice is also suggested by other major long-term evidence in the Mediterranean region. The numerous geodetic vectors available in two Adriatic sectors, the Apulia zone and the Venetian plain, would imply an Adria-Eurasia rotation pole incompatible with all Nubia-Eurasia Eulerian poles so far proposed. Since a significant relative motion between these plates is not compatible with the absence of a tectonic decoupling zone, we suppose that the short-term kinematics of Adria might be influenced by a transient non-rigid behaviour of that plate. This hypothesis is compatible with the expected effects (post seismic relaxation) of the major decoupling earthquakes that have occurred along Periadriatic zones in the past tens of years. The compatibility of the GPS kinematic pattern in the Apennine belt, Calabria Arc and Sicily with the implications of the geodynamic/tectonic interpretations so far proposed for the central Mediterranean area is then discussed.

Major seismic activity in the Northern Apennines concentrates in few zones, distributed in a peculiar way. It is argued that such context may be plausibly explained as an effect of belt-parallel shortening, which has caused oroclinal bending of the longitudinal ridges formed during the Late Miocene to Lower Pliocene evolutionary phase. The main effects of this process, developed since the upper Pliocene, have mainly affected the outer sectors of the belt. The major seismic sources have generated in the zones where different oroclinal bendings of adjacent ridges have produced extensional/transtensional deformation. In the inner side of the Northern Apennines, belt parallel shortening has occurred at a lower rate. The main effects have resulted from the shortening of the Albano-Chianti-Rapolano-Cetona ridge. In particular, the proposed tectonic setting may account for the moderate seismic activity that occurs in the Firenze, Elsa, Pesa, Siena and Radicofani basins.

SUMMARY An attempt at quantifying post-seismic relaxation triggered by decoupling earthquakes along the eastern thrusting border of the Adriatic plate (southern Dinarides) is carried out by finite element modelling, with a model constituted by an elastic lithosphere riding on a viscous asthenosphere. In particular, it is investigated the possibility that the above phenomenon is responsible for the fact that in the last two centuries most major earthquakes in the southern Dinarides (MS > 6) have been followed, within a few years, by intense, mainly tensional, earthquakes in southern Italy, i.e. the zone lying on the opposite margin of the Adriatic plate. This analysis has been applied to the last example of the supposed seismic interrelation, i.e. the triggering 1979 April 15 Montenegro event (MS= 6.7) and the presumably induced 1980 November 23 Irpinia earthquake in the southern Apennines (MS= 6.9). Results indicate that the strain induced in the southern Apennines by the triggering event has significant amplitude, since it largely exceeds the effect of earth tides, and the principal stress axes are consistent with those of southern Apenninic earthquakes. The order of magnitude of the time delay between the Montenegro and Irpinia events (1.6 yr) could be explained by assuming that earthquake triggering is most probable when the highest values of the induced strain rate reach the southern Apennines. In particular, this interpretation predicts the observed time delay when a model diffusivity of 400 m2 s−1 is assumed. The constraints that this diffusivity value may pose on the structural and rheological features of the crust–upper-mantle system in the study area are discussed. It is shown that the effects of the Montenegro event on the present velocity field are comparable to, though systematically lower than, the velocities suggested by geodetic observations in the Italian region. This suggests that geodynamic interpretations of geodetic data given without taking into account possible transient effects on the kinematic pattern, as those related to post-seismic relaxation, may be incorrect. Experiments carried out by tentatively simulating the presence of subducted lithosphere along the western margin of the Adriatic plate as a lateral variation of diffusivity, have shown that this structural feature may emphasize E–W tensional strains in the southern Apennines.

The evolution of the Mediterranean area since the Oligocene-Lower Miocene has been driven by the convergence of the surrounding plates. This implies that the observed deformation pattern in that region must be the most convenient shortening pattern, i.e. the one controlled by the minimum action principle. To understand why the fulfilment of such condition has required a complex spatio-temporal distribution of major tectonic events, such as uplift, lateral displacement and bending of orogenic belts, consumption of large lithospheric domains and formation of back arc basins, it may be very useful to take into account a basic tectonic concept, which helps to identify the process that can minimize the resistance of tectonic forces. Such concept starts from the fact that the most convenient consumption process is the one that involves low buoyancy oceanic lithosphere (Tethyan domains). However, such process is highly favoured where the oceanic lithosphere is stressed by vertical forces, a situation that develops when orogenic wedges are forced to over thrust and load the oceanic domain to be consumed. This interpretation can provide plausible and coherent explanations for the complex pattern of the observed deformations. In this view, the generation of back arc basins is taken as a side effect of an extrusion process, as suggested by numerical and mechanical experiments.

The location and age of potassic and ultra-potassic magmatism, mostly recognized as derived from mantle sources hybridized by subducted crustal rocks, in the Tyrrhenian–Apennines system do not show any plausible causal relationship with the evolutionary history of subduction processes, reconstructed from the time pattern of accretionary activity in the Apenninic belt. On the other hand, since magmatism in the study area was always associated in space and time with major phases of crustal stretching, one could think that the uprise of magmas through the uppermost lithosphere is strictly conditioned by the occurrence of extensional tectonics and, in particular, by the formation of significant fractures in the upper brittle crust. This would imply that using the distribution of “subduction related” magmatism for recognizing the timing and location of paleosubduction processes could be misleading. The geochemical features of these magmas can provide information on the kind of tectonophysical processes which took place in the mantle during the previous evolution but, as far as we know, the delay between mantle hybridization and magmatic activity cannot easily be assessed.

Finite element modeling of the central–eastern Mediterranean region has been carried out to show that the recent/present deformation pattern of this zone, inferred from neotectonic observations and seismic strain rates, may be satisfactorily reproduced as effect of the relative motion of Africa and eastern Anatolia with respect to Eurasia. Numerical modeling involved 2D elastic elements in a plane-stress approximation. The model is constituted by a mosaic of poorly deformable blocks separated by much more deformable decoupling zones, representing consuming boundaries, extensional zones and transcurrent discontinuities, whose location and geometry have been deduced by neotectonic, morphological and seismological information. The calculated displacement field obtained with the modeling parametrization which allows to match the observed strain regimes is compatible with geodetic observations in the study area, but for the Hellenic Arc, where geodetic velocities are higher than those predicted by modeling. This discrepancy could be considerably reduced by adopting a higher deformability of the model in the Hellenic trench, but this condition would contrast with the Plio-Quaternary deformation pattern of the southern Aegean zone, which suggest a considerable slowdown of western Crete since the late Pliocene. Furthermore, geodetic velocities are considerably higher than the motion rates derived by moment tensor analysis in the Hellenic trench and in the internal Aegean area and cannot easily account for the low Quaternary deformation observed in the southern Aegean zone. The above discrepancy could be due to a difference between the “instantaneous” kinematic behavior of the Aegean zone, indicated by geodetic measurements, and the average behavior over longer time intervals, inferred from geological and seismological strain indicators.

A statistical analysis of the relations between macroseismic intensity and magnitude is presented. The examined data set contains earthquakes characterized by epicentral or maximum intensity ≥ VI which occurred in the Mediterranean region. As a first step, an empirical magnitude-intensity relationship has been determined by using the whole data set. Then, differences between experimental magnitude values and the ones expected on the basis of the empirical relationship have been correlated with some features related both to physical and data sources characteristics. On this basis, a distribution-free statistical approach has been developed to attempt a regionalization of the examined area, able to locally optimize the performances of magnitude-intensity relations. However, the results showed that data relative to larger events (intensity ≥ VII) are not sufficient to perform any reliable zonation of the area. Thus, well-constrained relationships determined for the whole Mediterranean region should be preferred to ill-defined local ones. Concerning smaller earthquakes (intensity VI), the analysis suggests that an efficient zonation could only be obtained if medium-scale variations (lower than 200 Km) are taken into account.

Systolic anterior motion of the mitral valve (MV) with dynamic left ventricular (LV) outflow tract obstruction is a well known phenomenon in hypertrophic cardiomyopathy, or other forms of hyper-dynamic LV function associated with hypovolemic states, or LV hypertrophy. We report three patients with MV prolapse in the absence of the above predisposing factors, who developed an LV outflow dynamic gradient during acute transient myocardial ischemia. An interaction between structural abnormalities of the mitral apparatus and ischemia-dependent LV shape deformity most likely accounted for the outflow gradient.

During the last two centuries, the most intense earthquakes ( M ≥ 6) in southern Italy have regularly occurred some years (less than 5) after the main activations of the southern Dinarides-Albania seismic zone. To explain this interrelation, we advance the hypothesis that the strong decoupling earthquakes at the Adriatic-Dinarides collisional border cause a perturbation of the strain and stress fields which propagates through the Adriatic plate with rates of some hundreds of km per year. When this migrating perturbation reaches the opposite border of the Adriatic plate it may induce seismic dislocations in the highly fractured southern Apennines and Calabrian arc. Statistical tests have been carried out to estimate the reliability of possible Balkan seismic precursors of Italian earthquakes. The best results have been obtained with a precursor represented by the occurrence of at least one earthquake with M ≥ 6.5 or at least two shocks with M ≥ 6.0, assuming an alarm time of five years. In this case, the probabilities of a successful prediction (i.e. the occurrence of an event with M ≥ 6.0 in southern Italy within five years from the Balkan precursor) and of a non-alarm are 83% and 10%, respectively, and the probability of obtaining these results by chance is very low, less than 0.1%.

Insights into the present vertical kinematic pattern in Central and Northern Italy are gained by the analysis of GPS data acquired by a network of 262 permanent stations, working over various time intervals since 2001. Uplift is observed in the Alps (up to 5 mm/yr) and Apennines (1–2 mm/yr), whereas subsidence is recognized in the southern Venetian Plain (2–4 mm/yr) and the eastern Po Valley, where the highest rates are observed (up to 9 mm/yr between Reggio Emilia and Rimini). On the other hand, the western part of the Po Valley presents very low vertical rates. The boundary between subsiding and not subsiding Po Valley nearly corresponds to the Giudicarie tectonic discontinuity. It is argued that the different kinematic patterns of the eastern and western Padanian sectors may also be related to the underthrusting of the eastern domain beneath the western one. Some considerations are then reported on how the various causes of vertical movements (tectonic and sedimentological processes) may contribute to the observed kinematics.

It is widely accepted that the northern, central and southernmost Tyrrhenian basins opened up during three extensional phases, clearly differentiated in time (upper Tortonian to Messinian, late Messinian to upper Pliocene, late Pliocene to Present) and characterized by rather different deformation patterns in the surrounding Appenninic belt and Adriatic-Ionian foreland. Here, it is argued that the peculiar evolution mentioned above and several other major post-Tortonian deformation events in the central Mediterranean region can be coherently explained as direct consequences or side effects of the shortening processes, which accommodated the Africa-Eurasia convergence. These processes mainly consisted in the eastward and SEward lateral escape of buoyant crustal wedges of the Apenninic belt, at the expense of the adjacent Adriatic-Ionian foreland, which sunk into the underlying mantle, after decoupling from its buoyant cover. The extensional episodes which formed the Tyrrhenian basins were connected with local block divergences in the framework of an overall compressional regime. The principal changes of deformation styles which occurred around the upper Tortonian, the Messinian and the late Pliocene are attributed to the occurrence of major tectonic events, which modified the distribution of resistive forces in the zone considered. The final stage of the proposed evolutionary pattern can provide plausible explanations for the main shallow and deep structural tectonic features evidenced by geophysical observations.

It is widely believed that the Africa-Eurasian relative motion in the Mediterranean region is oriented SE-NW to S-N. This result has been deduced from the analysis of North Atlantic kinematic data by assuming that Eurasia is a unique coherent plate from the North Atlantic ridges to the Pacific trenches. However, this assumption cannot easily account for the not negligible tectonic activity inside and around Western Europe (Rhine Graben system, Pyrenees and off-shore Portugal). This paper shows that, if one allows Western Europe to move independently from main Eurasia, the kinematic indicators in the North Atlantic do not exclude other kinematic solutions which are significantly different from those currently accepted. In particular, it is demonstrated that a SSW-NNE to SW-NE trending Africa-Eurasia convergence, beside allowing plausible explanations of major post-Tortonian deformation events in the Central Mediterranean region, can fit North Atlantic data within experimental errors.

The geodetic data acquired in the last 10 years by a fairly dense network of permanent GPS stations located in Central and Northern Italy are used to reconstruct the present horizontal velocity field in the study area and to evaluate the coseismic and postseismic effects of the recent L’Aquila earthquake (April 6, 2009 Mw = 6.3). The distribution of geodetic velocities indicates that during the observation period the outer Adriatic sector of the Central and Northern Apennines has moved faster than the surrounding zones. It is pointed out that this short term kinematic behaviour is compatible with the long term kinematics indicated by the post-early Pleistocene deformation pattern observed in the central Mediterranean area. The short term kinematic pattern in the Central Apennines has been perturbed by the L’Aquila earthquake. The daily position time series of the sites located within 140 km from the epicentre show a coseismic offset followed by a non linear time dependent displacement which gradually vanishes in 1–3 months, after which the trend of daily positions seems to become linear again. The non linear transient phase has been modelled by a decaying exponential function, possibly connected with postseismic viscoelastic relaxation. The displacements developed during this last phase are rather different from coseismic displacements. Also, the velocities tentatively deduced from the postseismic linear trends (observed for about 17 months) show quite different orientations with respect to both coseismic and short term postseismic displacements. This evidence suggests that the tectonic processes which developed in the Central Apennines after the L’Aquila event were complex, possibly related to shallow afterslip, deeper aseismic slip and viscoelastic relaxation of the lower crust and/or uppermost mantle.

The strong earthquake ( M = 7) that occurred in the Fucino basin (central Italy) on January 13, 1915 was followed by six earthquakes of M > 5.5 and several other shocks of M > 5 in the major seismic zones of the northern Apennines from 1916 to 1920. This seismicity pattern is consistent with the implications of the present tectonic setting in the study area, which suggests that strong decoupling earthquakes in the central Apennines cause a significant increase of tectonic load, and possibly of seismicity, in the northern Apennines. A numerical simulation, carried out by an elastic-viscous model, of the stress diffusion induced by the Fucino and successive largest earthquakes, shows that each of the above shocks occurred when the respective zone was reached by the highest values of the strain and strain rate perturbation triggered by the previous events. Furthermore, the computed strain regime at each earthquake site is consistent with the known faulting pattern. The results provide important insights into the physical mechanism that controls the interaction of seismic sources in the central and northern Apennines.

International audience; We argue that the study of long-range interaction between seismic sources in the peri-Adriatic regions may significantly contribute to estimating seismic hazard in Italy. This hypothesis is supported by the reconstruction of the geodynamic and tectonic settings in the Central Mediterranean region, the space–time distribution of major past earthquakes, and the quantification of post-seismic relaxation. The most significant evidence of long-distance interaction is recognized for the Southern Apennines, whose major earthquakes have almost regularly followed within a few years the largest events in the Montenegro-Albania zone since 1850. Statistical analyses of the post-1850 earthquake catalogues give a probability of about 10% that a major event in the Southern Apennines is not preceded by the occurrence of a strong event in the Southern Dinarides–Albanides within 3–5 years. Conversely, the probability of false alarms is relevant (50% within 3 years, 33% within 5 years). Northward, the tectonic setting and some patterns of regularity seen in major events suggest that the seismic activation of the main transtensional decoupling shear zones in the Central Apennines should influence the probability of major earthquakes in the Northern Apennines.

The identification of a reliable geodynamic/tectonic model for the Italian region would be extremely useful for several practical purposes, in particular for quantifying the parameters to be used for seismic hazard assessment. In this work, we argue that the model presently adopted as a basis for elaborating the seismic classification of the Italian territory (MELETTI et alii, 2000) is not compatible with several major features of the observed deformation pattern and that, consequently, such choice should be reconsidered, taking into account an alternative geodynamic model that can much better explain the major tectonic events occurred in the central Mediterranean region since the late Miocene.

The formation of the Tyrrhenian–Apennines system has been characterized by a complex distribution of major tectonic events, such as opening of basins, migration and distortion of orogenic belts, retreat of trench zones, stopping of consuming processes and starting of new subductions. The various aspects of each event, such as timing, location, dimension and deformation style, impose important constraints on the genetic mechanism. In this work we argue that the numerous constraints implied by all events together may be plausibly and coherently explained as effects of the convergence of the confining Africa, Arabia and Eurasia plates. Crucial evidence for discriminating among the various geodynamic hypotheses so far advanced is provided by the structural/tectonic information recently provided by CROP seismic sections in the study area. The proposed evolutionary history is illustrated by several paleogeographic maps, which provide a more detailed reconstruction than previous attempts. Particular attention is paid to describing the tectonic setting developed since the middle Pleistocene in the Apennines belt and its connection with seismic activity.

The Adriatic platform has been described in the literature both as an Africa promontory, moving in close connection with the main continent and as an independent microplate. This evident incongruity is mainly due to the wide spectrum of kinematic hypotheses proposed on the basis of paleomagnetic data and to the fact that the Adriatic-Africa transition is not marked by any clear decoupling fracture or by any interruption of lithological facies along the marginal belts (Apennines-Maghrebides and Dinarides-Hellenides). In this work it is argued that the counterclockwise rotation of the Adriatic plate, driven by Africa pushing beneath the Calabrian Arc and southern Tyrrhenian, may coherently account for all major Plio-Quatemary events in the central Mediterranean.

Previous works have proposed gravitational collapse as the driving mechanism of extensional deformation of thickened continental crust. In this work we investigate the physical plausibility of this interpretation for the most important orogenic belts of the world by computing the spreading force induced by lateral variations of crustal thickness and the possible resisting forces. Two collapse mechanisms, one involving the upper crust only and the other the whole crust, have been considered. Particular attention has been devoted to constrain the uncertainty affecting such computations, mostly due to the large variability of the thermal and mechanical properties of rocks. The results obtained show that gravitational collapse is not a plausible mechanism in the four Mediterranean orogens here considered (Northern Apennines, Calabrian Arc, Hellenic Arc and Carpathians). For the other orogenic zones we have taken into account (Western U.S. Cordillera, Central Andes, Himalayas and Central Alps), the large uncertainty that affects the estimate of spreading and resisting forces does not allow to firmly assess the feasibility of gravitational collapse.

Calcification of the mitral annulus is a common echocardiographic finding in the elderly, particularly in females. Calcium deposits are generally located in the posterior mitral ring, sometimes extending to the whole mitral annulus and involving the mitral valve apparatus. The present report refers to 2 patients with a very atypical mass-like calcification of the mitral annulus resembling a cardiac tumor. A detailed evaluation of the mass was obtained at transthoracic and transesophageal echocardiography; the differential diagnosis with other intracardiac masses was aided by the use of computed tomography and magnetic resonance imaging. To our knowledge there has been no prior report of such a lesion evaluated at cardiac magnetic resonance imaging.

[1] It is shown, by numerical modeling, that the recent deformation pattern observed in the northern Apennines, mainly characterized by progressive eastward migration and bowing of the belt, thrusting activity along its external front, and tensional tectonics in the internal area, can be reproduced, at a first approximation, by applying a belt-parallel (SE-NW) compression to the chain, which is simulated as a structural system characterized by a high mechanical strength and decoupled from the surrounding zones. The above compressional regime, obtained by imposing kinematic boundary conditions to the model, causes the outward escape of crustal wedges from the chain, in particular the northeastward displacement of the Romagna-Marche-Umbria Units and the counterclockwise rotation and northwestward displacement of the Ligurian Units. This kinematics produces compressional to transcompressional strain along the external front of the chain and tensional to transtensional strain in the internal area, in line with the observed features that concern both strain style and orientation of principal strains. Evidence and arguments supporting the kinematic boundary conditions and the model parameterization adopted in modeling are discussed. Numerical experiments have also been carried out to evaluate the influence of major features of the model parameterization and boundary conditions we have adopted in modeling and to provide insights into the possible influence of strong decoupling earthquakes in the central Apennines on tectonic and seismic activity in the northern Apennines.

The space-time distribution of deformation in the central Mediterranean area suggests that the Adriatic domain (Adria) has moved coherently with Africa up until the late Miocene and that, subsequently, it decoupled from Africa (Nubia) and underwent a clockwise (CW) rotation with respect to Eurasia. This event was determined by the westward push of the Anatolian- Aegean-Balkan system, after its collision with the southern Adriatic continental domain. The CW rotation of the Adria microplate induced a strong compressional regime in the central Mediterranean region, which can account for the major tectonic events that occurred in this zone since the late Miocene. These include the renewal of accretionary activity in the Apenninic belt, the opening of the central Tyrrhenian basin, the detachment of the Iblean microplate from mainland Africa and the development of a major fracture in the northern Adriatic foreland. The CW rotation of the Adria plate came to an end around the late Pliocene-early Pleistocene due to the collision of the Adria continental domain with the Southern Apennines. After this event, Adria has undergone a slow CCW rotation with respect to Eurasia. This kinematic pattern during the last evolutionary phase is suggested by the distribution of Quaternary deformation in the peri-Adriatic zones, in particular the shortening recognized at the eastern (Dinarides-Hellenides) and northern (southern Eastern Alps) boundaries of Adria, and is consistent with the seismological and geodetic evidence in the Adriatic and peri-Adriatic regions. No significant recent deformation can be recognized between Adria and Africa, at the Pliocene decoupling zone or at any other possible decoupling tectonic belt. This suggests no, or at most very little, relative motion between these two domains during the Quaternary. The possible implications of this last evidence on Nubia-Eurasia kinematics are discussed.

SUMMARY The most reliable and significant seismological and geodetic constraints on the kinematics of the Adriatic Plate are tentatively recognized and used for determining Adriatic–Eurasia Eulerian poles. The poles so obtained, in spite of the considerable uncertainty that might affect them, significantly differ from the ones of previous studies. Possible explanations of this discrepancy are discussed. It is then argued that the distribution of Quaternary deformation and seismotectonic activity in the Adriatic and surrounding regions suggests that no appreciable relative motion can be recognized between the Adriatic and Africa. This evidence implies that the kinematics of the Adriatic may provide a constraint on the motion of Africa in the central Mediterranean region.