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Subduction of the Neotethys Ocean resulted in collisions of continental plates, with formation of Cenozoic orogens. The different shapes and structures of various segments of these young orogens, such the Zagros Collisional Zone, suppose a complex interplay of shallow and deep structures, producing different degrees and styles of deformation. As part of the PRIN 2017 project, we analyze several types of recently acquired data (e.g., seismic tomography models of the crust and upper mantle, Moho depth, seismicity distribution, and surface topography). We find that the NW and central Zagros is characterized by a zone of thickened crust of variable width and overlain by topography that exhibits large height variations over small distances, in the central part of the collisional zone. These variations are accompanied by sharp lateral changes in the number of seismic events and velocities/temperatures at depths of ~100 km. We attribute these observations to relamination processes (i.e., the detachment of Arabian crust from the subducting lithospheric mantle and its underthrusting beneath the crust of the overriding plate), which are controlled by the variable geometry and stiffness of the overriding and subducting plates. This hypothesis is tested by performing a series of numerical experiments, using the numerical code I2VIS [1], that simulates relamination processes, occurring during continental collision. The consistency of the results is also verified through forward models of the static gravity field of the modelled structures, which are compared with the present-day observed gravity.References[1] Gerya, T.V., 2019. Cambridge University Press. ISBN 978-0-521-88754-0., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The GRACE/GRACE-FO satellites have observed large scale mass changes, contributing to the mass budget calculation of the hydro-and cryosphere. The scale of the observable mass changes must be in the order of 300 km or bigger to be resolved. Smaller scale glaciers and hydrologic basins significantly contribute to the closure of the water mass balance, but are not detected with the present spatial resolution of the satellite. The challenge of future satellite gravity missions is to fill this gap, providing higher temporal and spatial resolution. We assess the impact of a geodetic satellite mission carrying on board a cold atom interferometric gradiometer (MOCASS: Mass Observation with Cold Atom Sensors in Space) on the resolution of simulated geophysical phenomena, considering mass changes in the hydrosphere and cryosphere. Moreover, we consider mass redistributions due to seamounts and tectonic movements, belonging to the solid earth processes. The MOCASS type satellite is able to recover 50% smaller deglaciation rates over a mountain range as the High Mountains of Asia compared to GRACE, and to detect the mass of 60% of the cumulative number of glaciers, an improvement respect to GRACE which detects less than 20% in the same area. For seamounts a significantly smaller mass eruption could be detected with respect to GRACE, reaching a level of mass detection of a submarine basalt eruption of 1.6 109 m3. This mass corresponds to the eruption of Mount Saint Helens. The simulations demonstrate that a MOCASS type mission would significantly improve the resolution of mass changes respect to existing geodetic satellite missions.

Both GRACE and GOCE have proven to be very successful missions, providing a wealth of data which are exploited for geophysical studies such as climate changes, hydrology, sea level changes, solid Earth phenomena, with benefits for society and the whole world population. It is indispensable to continue monitoring gravity and its changes from space, so much so that a GRACE follow-on mission has been launched in 2018. In this paper, a new satellite mission concept named MOCASS is presented, which can be considered as a GOCE follow-on, based on an innovative gradiometer exploiting ultra-cold atom technology and aimed at monitoring Earth mass distribution and its variations in time. The technical aspects regarding the payload will be described, illustrating the measurement principle and the technological characteristics of a cold atom interferometer that can measure gravity gradients. The results of numerical simulations will be presented for a one-arm and a two-arm gradiometer and for different orbit configurations, showing that an improvement with respect to GOCE could be obtained in the estimate of the static gravity field over all the harmonic spectrum (with an expected error of the order of 1 mGal at degree 300 for a 5-year mission) and that estimates are promising also for the time-variable gravity field (although GRACE is still performing better at very low degrees). Finally, the progress achievable by exploiting MOCASS observations for the detection and monitoring of geophysical phenomena will be discussed: the results of simulations of key geophysical themes (such as mass changes due to hydrology, glaciers and tectonic effects) with expected gravity change-rates, time constants and corresponding wavelengths, show that an improvement is attainable and that signals invisible to past satellites could be detected by exploiting the cold atom technology.

Water supply from karst sources is a worldwide natural resource and the exploitation is tied to the knowledge of the positions of the hydrologic channels. We show that surface deformation induced by flood events in karst conduits is observable, and consists in uplift and outward movement from the hydraulic channel. Precipitation events produce the natural occurrence of subsurface hydraulic overpressure up to 1 MPa. Numerical modeling shows that the stresses are so strong to uplift and dislocate the surface by several mm and induce tilts in the order of microradians. The naturally induced deformation is compatible with a transient internal pressure loading of a channel. The results can be used to find new channels with dense GNSS networks. Sea water incursion and channels accessed for tourism could be monitored. Seismicity has been shown to have a seasonal variation in some areas, which could be explained by the subsurface stresses induced by the natural subsurface overpressure. The pressure induced deformation is expected to be observed in all karstic systems worldwide.

Malignant pleural mesothelioma (MPM) is a rare and aggressive form of tumour. Some mesotheliomas have been proven to be highly immunogenic. Here, we investigated the correlation between tumour infiltrating lymphocytes (TILs) or programmed cell death ligand 1 (PD-L1) expression with overall survival (OS) in patients with MPM. 62 Paraffin-embedded formalin fixed (PEFF) samples were analysed for TILs and PD-L1 expression. Patients were divided in 4 groups according to a cut-off of the percentage of TILs found per sample as measured by immunohistichemistry: “0” or absent (between 0 and 5%), “1” or low (between 6 and 25%), “2” or moderate (between 26 and 50%) and “3” or high (between 51 and 75%). OS was then correlated with different TILs’ expression patterns. Moreover, PD-L1 expression was assessed within the tumour as well as in the adjacent stroma on the same samples. Higher expression of peritumoral TILs (Group 2 + 3) versus Group 0 and 1 correlated with improved OS (p-value = 0.02). On the contrary PD-L1 expression seemed to be inversely correlated with clinical outcomes, even in the absence of statistical significance (HR 1.76; p = 0.083 95% IC 0.92–3.36 in areas within the tumour; HR 1.60; p = 0.176 95%; IC 0.80–3.19 in areas within the stroma). No relationship between TILs and PD-L1 expression was identified. Our research supports the use of TILs and PD-L1 expression as potential outcome predictors in patients with MPM. The use of TILs and PD-L1 as biomarkers for checkpoint inhibitors’ efficacy warrants future investigation.