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Fluids can modify the mechanical properties of rocks, including shear strength and strain behavior. We investigate the timing and magnitude of seismic events during fault motion in strike–slip systems across the Peloritani Mountains (northeastern Sicily) and Aeolian Archipelago using GNSS and seismological data analysis. Results reveal a strain partitioning along the already known crustal–scale NNW–SSE trending right–lateral transtensional deformation zone across the Peloritani Mts and its offshore extension up to Vulcano Island (defined as the Aeolian–Tindari–Letojanni Fault System, ATLFS), and WNW–ESE to NW–SE right–lateral transfer zones located in the western and central sectors of the Aeolian Archipelago. During 2021, the eastern block of the ATLFS underwent a significant velocity increase relative to the fixed western block, varying from 1.6 ± 0.28 mm/y (pre–2021 baseline) to 3.3 ± 0.99 mm/y. The acceleration of the eastern block of the ATLFS was accompanied by increased seismic strain release. It temporally correlated with the fastest ground inflation on Vulcano Island (central Aeolian Archipelago), which in turn coincided with the highest CO2 flux emission on the island. This correlation, along with evidence of gas emissions in the Peloritani Mts, suggests that enhanced fluid pressure lubricated fault surfaces, thereby facilitating slip along the ATLFS. The fluid–induced slip acceleration was sustained for 9 months and was marked by frequent low–magnitude earthquakes.

This study presents the results of an experimental investigation conducted on a 2:3 scale model of a two-story stone masonry building. We tested the model on the UniKORE L.E.D.A. lab shake table, simulating the Mw 6.3 earthquake ground motion that struck L’Aquila, Italy, on 6 April 2009, with progressively increasing peak acceleration levels. We installed a network of accelerometric sensors on the model to capture its structural behaviour under seismic excitation. Medium-to lower-cost MEMS accelerometers (classes A and B) were compared with traditional piezoelectric sensors commonly used in Structural Health Monitoring (SHM). The experiment assessed the structural performance and damage progression of masonry buildings subjected to realistic earthquake inputs. Additionally, the collected data provided valuable insights into the effectiveness of different sensor types and configurations in detecting key vibrational and failure patterns. All the sensors were able to accurately measure the dynamic response during seismic excitation. However, not all of them were suitable for Operational Modal Analysis (OMA) in noisy environments, where their self-noise represents a crucial factor. This suggests that the self-noise of MEMS accelerometers must be less than 1 µg/√Hz, or preferably below 0.5 µg/√Hz, to obtain good results from the OMA. Therefore, we recommend ultra-low-noise sensors for detecting differences in the structural behaviour before and after seismic events. Our findings provide valuable insights into the seismic vulnerability of masonry structures and the effectiveness of sensors in detecting damage. The management of buildings in earthquake-prone areas can benefit from these specifications.

The high seismic productivity of volcanic areas provides the chance to investigate the local stress conditions with great resolution, by analysing the slope of the frequency-magnitude distribution of earthquakes, namely the b- value. Here we investigated the seismicity of Mt. Etna between 2005 and 2019, focusing on one of the largest known episodes of unrest in December 2018, when most of the intruding magma aborted, rather oddly, its ascent inside the volcano. We found a possible stress concentration zone along magma pathways, which may have inhibited the occurrence of a larger eruption. If the origin of such hypothetical loaded region is related to tectonic forces, one must consider the possibility that geodynamic processes can locally result in such rapid crustal strain as to perturb the release of magma. Strong b- value time-variations occurred a few days before the unrest event, suggesting new possibilities for investigating the volcano state and impending eruptions.

We describe the first dense real-time urban seismic–accelerometric network in Italy, named OSU-CT, located in the historic center of Catania. The city lies in the region with the greatest danger, vulnerability, and earthquake exposure in the entire Italian territory. OSU-CT was planned and realized within the project called EWAS “an Early WArning System for cultural heritage”, aimed at the rapid assessment of earthquake-induced damage and the testing of an on-site earthquake early warning system. OSU-CT is mainly based on low-cost instrumentation realized ad hoc by using cutting-edge technologies and digital MEMS (micro-electro-mechanical systems) triaxial accelerometers with excellent resolution and low noise. Twenty of the forty scheduled stations have already been set up on the ground floor of significant historic public buildings. In order to assess the performance of an earthquake early warning (EEW) on-site system, we also installed wide-band velocimeters (ETL3D/5s) in three edifices chosen as test sites, which will be instrumented for a structural health monitoring (SHM). In addition to several laboratory and field validation tests on the developed instruments, an effective operational test of OSU-CT was the Mw 4.3 earthquake occurring on 23 December 2021, 16 km west, south-west of Catania. Peak ground accelerations (4.956 gal to 39.360 gal) recorded by the network allowed obtaining a first urban shakemap and determining a reliable distribution of ground motion in the historical center of the city, useful for the vulnerability studies of the historical edifices.

From January 2011 to December 2015, Mt. Etna was mainly characterized by a cyclic eruptive behavior with more than 40 lava fountains from New South-East Crater. Using the RMS (Root Mean Square) of the seismic signal recorded by stations close to the summit area, an automatic recognition of the different states of volcanic activity (QUIET, PRE-FOUNTAIN, FOUNTAIN, POST-FOUNTAIN) has been applied for monitoring purposes. Since values of the RMS time series calculated on the seismic signal are generated from a stochastic process, we can try to model the system generating its sampled values, assumed to be a Markov process, using Hidden Markov Models (HMMs). HMMs analysis seeks to recover the sequence of hidden states from the observations. In our framework, observations are characters generated by the Symbolic Aggregate approXimation (SAX) technique, which maps RMS time series values with symbols of a pre-defined alphabet. The main advantages of the proposed framework, based on HMMs and SAX, with respect to other automatic systems applied on seismic signals at Mt. Etna, are the use of multiple stations and static thresholds to well characterize the volcano states. Its application on a wide seismic dataset of Etna volcano shows the possibility to guess the volcano states. The experimental results show that, in most of the cases, we detected lava fountains in advance.

Key Clinical Message Stenotrophomonas maltophilia can cause rare odontogenic brain abscesses in immunocompetent patients, highlighting the importance of considering uncommon pathogens in central nervous system infections. With only three reported cases of cerebral abscesses and one pituitary abscess caused by this microorganism, tailored diagnostic methods and individualized treatment regimens are crucial for accurate management. Brain abscesses present diagnostic and therapeutic challenges, with Stenotrophomonas maltophilia infections being exceptionally rare in the central nervous system. We present a case of odontogenic brain abscesses caused by S. maltophilia in an immunocompetent patient, highlighting the rarity and complexity of such infections. A 66‐year‐old male presented with spatial–temporal disorientation and left‐sided weakness. Radiological investigations revealed an expansive lesion in the right posterior frontal region. A craniotomy and drainage were performed, identifying S. maltophilia in the purulent material. The patient responded well to tailored antibiotic therapy. S. maltophilia‐related central nervous system infections are infrequent, emphasizing the need for a heightened clinical suspicion in atypical cases. This case contributes to the literature, emphasizing the importance of a multidisciplinary approach for successful diagnosis and management.

After the subsidence phase that followed the 1982–1984 bradyseismic crisis, a gradual ground uplift at Campi Flegrei caldera resumed in 2005, while volcanic-tectonic earthquakes have steadily increased in frequency and intensity since 2018, with a significant intensification observed since 2023. This rise in seismic activity enabled a new tomographic study using data collected from 2020 to June 2024. In this work, 4161 local earthquakes (41,272 P-phases and 14,683 S-phases) were processed with the tomoDDPS code, considering 388,166 P and 107,281 S differential times to improve earthquake locations and velocity models. Compared to previous tomographic studies, the 3D velocity models provided higher-resolution images of the central caldera’s structure down to ~4 km depth. Additionally, separate inversions of the two 2020–2022 (moderate seismicity) and 2023–2024 (intense seismicity) datasets identified velocity variations ranging from 5% to 10% between these periods. These changes observed in 2023–2024 support the existence of two pressurized sources at different depths. The first, located at 3.0–4.0 km depth beneath Pozzuoli and offshore, may represent either a magma intrusion enriched in supercritical fluids or an accumulation of pressurized, high-density fluids—a finding that aligns with recent ground deformation studies and modeled source depths. Additionally, the upward migration of magmatic fluids interacting with the geothermal system generated a secondary, shallower pressurized source at approximately 2.0 km depth beneath the Solfatara-Pisciarelli area. Overall, these processes are responsible for the recent acceleration in uplift, increased seismicity and gases from the fumarolic field, and changes in crustal elastic properties through stress variations and fluid/gas migration.

Influences of distant earthquakes on volcanic systems by dynamic stress transfer are well documented. We analyzed seismic signals and volcanic activity at Mount Etna during two periods, January 2006 and May 2008, that clearly showed variations coincident with distant earthquakes. In the first period, characterized by mild volcano activity, the effect of the dynamic stress transfer, caused by an earthquake in Greece (M = 6.8), was twofold: (1) banded tremor activity changed its features and almost disappeared; (2) a swarm of volcano‐tectonic (VT) earthquakes took place. The changes of the banded tremor were likely due to variations in rock permeability, caused by fluid flows driven by dynamic strain. The VT earthquake swarm probably developed as a secondary process, promoted by the dynamically triggered activation of magmatic fluids. The second period, May 2008, showed an intense explosive activity. During this interval, the dynamic stress transfer, associated with the arrival of the seismic waves of the Sichuan earthquake (M = 7.9), affected the character of the seismo‐volcanic signals and on the following day triggered an eruption. In particular, we observed changes in volcanic tremor and increases of both occurrence rate and energy of long period events. In this case, we suggest that dynamic stress transfer caused nucleation of new bubbles in volatile‐rich magma bodies with consequent buildup of pressure, highlighted by the increase of long period activity, followed by the occurrence of an eruption. We conclude that stresses from distant earthquakes are capable of modifying the state of the volcano.

After a period of deflation during the 1991-1993 flank eruption, Mount Etna underwent a rapid inflation. Seismicity and ground deformation show that since 1994, a huge volume of magma intruded beneath the volcano, producing from 1998 onward a series of eruptions at the summit and on the flank of the volcano. The last of these, started on 27 October 2002, is still in progress and can be considered one of the most explosive eruptions of the volcano in recent times. Here we show how geodetic data and seismic deformation, between 1994 and 2001, indicate a radial compression around an axial intrusion, consistent with a repressurization of Mount Etna's plumbing system at a depth of 6 to 15 kilometers, which triggered most of the seismicity and provoked the dilatation of the volcano and the recent explosive eruptive activity.

To evaluate the safety and efficacy of lattice radiotherapy (LRT) for large, inoperable breast cancers. In this prospective study, patients who underwent LRT for breast tumors that were ulcerating/fungating/extensively eroding the chest wall, and were ineligible/unwilling for surgery, were enrolled from May 2021 to Nov 2023. Baseline Eastern Cooperative Oncology Group (ECOG) status, pre- and post-LRT numerical rating scale (NRS), and post-LRT changes in quality of life (QoL) were recorded. Survival outcomes were reported at 6 months and 1-year. Median rates of survival and dosimetric parameters were calculated. Kaplan-Meier curves for overall survival (OS), cancer-specific survival (CSS), and failure of local control (LC) were constructed. Ten patients (8 females) underwent LRT. The median age was 76 years (range=57-99 years) and the median ECOG performance status was 2.5 (range=1-4). The planned schedule was completed by 9/10 patients, accounting for a 90% compliance rate. Among patients with pain (n=7), NRS rapidly reduced from 7 (range=5-10) to 3 (range=1-6). The median equivalent uniform dose was 0.71 Gy (0.09-1.59 Gy). The actuarial rates of 6-month LC, CSS, and OS were 75%, 89%, and 61%, respectively, with only LC rate changing to 50% at 1 year. Two patients had local relapse at the six-month and 1-year follow-up, respectively, after having achieved a complete response at three months, and two others died of COVID-19 infection and ischemic stroke. LRT was found to be effective and safe in palliating symptoms among patients with large inoperable breast tumors.