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Cellular mechanical metamaterials are a special class of materials whose mechanical properties are primarily determined by their geometry. However, capturing the nonlinear mechanical behavior of these materials, especially those with complex geometries and under large deformation, can be challenging due to inherent computational complexity. In this work, we propose a data-driven multiscale computational scheme as a possible route to resolve this challenge. We use a neural network to approximate the effective strain energy density as a function of cellular geometry and overall deformation. The network is constructed by "learning" from the data generated by finite element calculation of a set of representative volume elements at cellular scales. This effective strain energy density is then used to predict the mechanical responses of cellular materials at larger scales. Compared with direct finite element simulation, the proposed scheme can reduce the computational time up to two orders of magnitude. Potentially, this scheme can facilitate new optimization algorithms for designing cellular materials of highly specific mechanical properties.

Background: Pulmonary infection with SARS-CoV-2 virus (severe acute respiratory syndrome coronavirus 2; COVID-19) has rapidly spread worldwide to become a global pandemic. Objective: To collect paediatric COVID-19 cases worldwide and to summarize both clinical and imaging findings in children who tested positive on polymerase chain reaction testing for SARS-CoV-2. Materials and methods: Data were collected by completion of a standardised case report form submitted to the office of the European Society of Paediatric Radiology from March 12 to April 8, 2020. Chest imaging findings in children younger than 18 years old who tested positive on polymerase chain reaction testing for SARS-CoV-2 were included. Representative imaging studies were evaluated by multiple senior paediatric radiologists from this group with expertise in paediatric chest imaging. Results: Ninety-one children were included (49 males; median age: 6.1 years, interquartile range: 1.0 to 13.0 years, range: 9 days–17 years). Most had mild symptoms, mostly fever and cough, and one-third had coexisting medical conditions. Eleven percent of children presented with severe symptoms and required intensive unit care. Chest radiographs were available in 89% of patients and 10% of them were normal. Abnormal chest radiographs showed mainly perihilar bronchial wall thickening (58%) and/or airspace consolidation (35%). Computed tomography (CT) scans were available in 26% of cases, with the most common abnormality being ground glass opacities (88%) and/or airspace consolidation (58%). Tree in bud opacities were seen in 6 of 24 CTs (25%). Lung ultrasound and chest magnetic resonance imaging were rarely utilized. Conclusion: It seems unnecessary to perform chest imaging in children to diagnose COVID-19. Chest radiography can be used in symptomatic children to assess airway infection or pneumonia. CT should be reserved for when there is clinical concern to assess for possible complications, especially in children with coexisting medical conditions. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.

Most of the research works that aim at explaining the relationships between tectonic and volcanism focused a single volcano or eruption. Conversely, this study investigated offshore and onshore areas of the Campania margin in terms of stratigraphy, tectonics, and volcanism at a regional scale. We documented and reconstructed the three-dimensional geometry of several buried volcanoes and volcaniclastic deposits and recognized a complex Late Quaternary tectonic evolution of the region. These results suggest a strict genetic link between rifting and volcanic activity in terms of space-time evolution and because high volumes of magma rose to the surface through regional faults.

Most of the research works that aim at explaining the relationships between tectonic and volcanism focused a single volcano or eruption. Conversely, this study investigated offshore and onshore areas of the Campania margin in terms of stratigraphy, tectonics, and volcanism at a regional scale. We documented and reconstructed the three-dimensional geometry of several buried volcanoes and volcaniclastic deposits and recognized a complex Late Quaternary tectonic evolution of the region. These results suggest a strict genetic link between rifting and volcanic activity in terms of space-time evolution and because high volumes of magma rose to the surface through regional faults.

Objectives To assess the role of fetal magnetic resonance imaging (MRI) in detecting associated anomalies in fetuses presenting with mild or moderate isolated ventriculomegaly (VM) undergoing multiplanar ultrasound evaluation of the fetal brain. Methods This was a multicenter, retrospective, cohort study involving 15 referral fetal medicine centers in Italy, the UK and Spain. Inclusion criteria were fetuses affected by isolated mild (ventricular atrial diameter, 10.0-11.9 mm) or moderate (ventricular atrial diameter, 12.0-14.9 mm) VM on ultrasound, defined as VM with normal karyotype and no other additional central nervous system (CNS) or extra-CNS anomalies on ultrasound, undergoing detailed assessment of the fetal brain using a multiplanar approach as suggested by the International Society of Ultrasound in Obstetrics and Gynecology guidelines for the fetal neurosonogram, followed by fetal MRI. The primary outcome of the study was to report the incidence of additional CNS anomalies detected exclusively on prenatal MRI and missed on ultrasound, while the secondary aim was to estimate the incidence of additional anomalies detected exclusively after birth and missed on prenatal imaging (ultrasound and MRI). Subgroup analysis according to gestational age at MRI (< 24 vs >= 24 weeks), laterality of VM (unilateral vs bilateral) and severity of dilatation (mild vs moderate VM) were also performed. Results Five hundred and fifty-six fetuses with a prenatal diagnosis of isolated mild or moderate VM on ultrasound were included in the analysis. Additional structural anomalies were detected on prenatal MRI and missed on ultrasound in 5.4% (95% CI, 3.8-7.6%) of cases. When considering the type of anomaly, supratentorial intracranial hemorrhage was detected on MRI in 26.7% of fetuses, while polymicrogyria and lissencephaly were detected in 20.0% and 13.3% of cases, respectively. Hypoplasia of the corpus callosum was detected on MRI in 6.7% of cases, while dysgenesis was detected in 3.3%. Fetuses with an associated anomaly detected only on MRI were more likely to have moderate than mild VM (60.0% vs 17.7%; P

The paper by De Natale et al. (2016, https://doi.org/10.1002/2015GC006183) reported new stratigraphic and geochronological data for a borehole located at Campi Flegrei volcanic area. The authors failed to mention several significant articles on the geological evolution of the region and proposed an interpretation of their data according to the caldera model. Herein, we provide tectonic and stratigraphic data to support a fault model of ignimbrite emission. This comment will also show the inconsistency of the proposed Campi Flegrei caldera.

In the Central Mediterranean the Africa-Eurasia convergence led to the development of complex orogenic systems and backarc basins. Throughout Pliocene-Quaternary times the Southern Apennines accretionary prism migrated towards the Apulia foreland and, contemporaneously, the Tyrrhenian Sea backarc basin opened. In this study, we investigated the offshore of the southern Apulia foreland and the Southern Apennines. Using seismic reflection profiles and well data in a dedicated GIS software, we made a detailed stratigraphic analysis, reconstructed the structural pattern and built 2D geological models of the main geological surfaces. The structure of the Apulia region formed during two main tectonic stages: lower Pleistocene complex extensional faulting developed in a transtensional regime and middle-upper Pleistocene transpression/shortening. The Southern Apennines accretionary prism developed through the Pliocene-early lower Pleistocene and was overprinted by late lower Pleistocene-middle Pleistocene NW-SE sinistral faults. Through linking new data from the accretionary prism and the foreland with previous information from the Tyrrhenian Sea back-arc, we provide an original interpretation for the relationships between the various provinces that make the Central Mediterranean crustal puzzle and reconstruct the main phases of the evolution of its Pliocene-Quaternary orogenic cycle. We recognized collisional stages of uncoupled plates, followed by late lower-middle Pleistocene post-collisional stages of coupled continental plates. This Pleistocene plates re-organization of Central Mediterranean was probably due to the rupture of the Apulia/Ionian slab or to NNW intraplate shortening transmitted from Africa.

Miocene extensional sedimentary basins are being increasingly recognized in Central Mediterranean. However the paleogeographic reconstruction of the Paleo-Tyrrhenian during this time span results a difficult task because the subsequent Pliocene-Quaternary backarc opening moved away these older sedimentary basins. Our study outlines principal deformation events recorded by sediments that were deposited within minor basins of the Tyrrhenian Sea region and provides constraints on the duration of these events. The interpretation of seismic profiles, wells, and outcrops data together with a review of the middle-upper Miocene successions permitted us to recognize Miocene third order depositional sequences, reconstruct the fault pattern, and furnish a detailed evolution of the sedimentary basins that preceded the Pliocene-Quaternary Tyrrhenian high stretching. Based on the stratigraphic and tectonic constraints together with the age migration of the depocenters, we reconstructed a detailed paleogeographic evolution of central Mediterranean. Sedimentary basins architecture and fault pattern indicate a system of approximately N-S oriented normal faults and approximately E-W transform faults that were active since the Late Oligocene. Two period of extensional/transtensional tectonics (late Oligocene-Lower Burdigalian and Upper Langhian-Tortonian) were interrupted by a compressional event (late Burdigalian-Lower Langhian). Tacking in account the position of the Miocene volcanic arc (Sardinia), we propose that the coeval sedimentary basins developed in the central Mediterranean as forearc extensional/transtensional basins during the progressive collision with the African plate and before the Tyrrhenian backarc opening. Unlike published late Oligocene-Tortonian reconstructions of the western-central Mediterranean realm that report a linear migration of backarc extension, our results support a geodynamic model characterized by a progressive deformation of the forearc extension in the overriding plate.

The development of premature ovarian failure and subsequent infertility are possible consequences of chemotherapy use in pre-menopausal women with early-stage breast cancer. Among the available strategies for fertility preservation, pharmacological protection of the ovaries using luteinising hormone-releasing hormone analogues (LHRHa) during chemotherapy has the potential to restore ovarian function and fertility after anticancer treatments; however, the possible efficacy and clinical application of this strategy has been highly debated in the last years. Following the availability of new data on this controversial topic, the Panel of the Italian Association of Medical Oncology (AIOM) Clinical Practice Guideline on fertility preservation in cancer patients decided to apply the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) methodology around the relevant and current question on the clinical utility of temporary ovarian suppression with LHRHa during chemotherapy as a strategy to preserve ovarian function and fertility in breast cancer patients. To answer this question, preservation of ovarian function and fertility were judged as critical outcomes for the decision-making. Three possible outcomes of harm were identified: LHRHa-associated toxicities, potential antagonism between concurrent LHRHa and chemotherapy, and lack of the prognostic impact of chemotherapy-induced premature ovarian failure. According to the GRADE evaluation conducted, the result was a strong positive recommendation in favour of using this option to preserve ovarian function and fertility in breast cancer patients. The present manuscript aims to update and summarise the evidence for the use of this strategy in light of the new data published up to January 2016, according to the GRADE process.

The Tyrrhenian Sea (Central Mediterranean) is an extensional area that formed during the collision between Africa and Eurasia. Through the analysis of well logs and seismic profiles we reconstructed the stratigraphic successions and the structural style of the Tyrrhenian sedimentary basins. The sequence stratigraphy interpretation of well logs permitted us to recognize third and fourth order depositional sequences and the stratigraphic signatures of the rift stages. The study area features several sediment overfilled/balanced infill basins that resulted from the superposition of several rifting events characterized by high rates of basin subsidence. These outcomes led us to propose five rifting episodes occurred from Miocene to Quaternary affecting the upper plate. The suggested geodynamic scenario takes into account a progressive rupture of the slab and formation of sedimentary basins in the upper plate.

The ground state of the linear harmonic oscillator is the solution to a minimization problem, and this opens up two new ways to completely solve Schrödinger’s time-independent equation. The first exploits systematic patterns that emerge from a formal relationship between two different integral representations of the energy. A remarkable invariant form of the ground-state probability-density equation under specific conditions is the leading principle of the second procedure, where a uniform notation for all mathematical object involved facilitates calculations and generates useful schemes to quickly deduce the main functional relationships of the problem. We believe these procedures may represent useful educational alternatives to standard treatments that address this fundamental problem.

Coeval rifting processes affecting both backarc, thrust belt and foreland occurred in offshore western Sicily (Central Mediterranean) as indicated by the analysis of a large seismic data set calibrated with well data, onshore data and dredges in a dedicated GIS software environment. Structural pattern of the investigated area, 3-D geological models and a Pliocene-Lower Pleistocene evolution of extensional sedimentary basins have been reconstructed. In detail, two zones characterized by basins with different directions of extension have been recognized: one trending NE-SW, located south of the Egadi Islands; another trending E-W, positioned north of the Egadi Islands. The first group of basins represents the continuation of those of the Africa foreland basin (Pelagian Block), as the second one characterizes the opening of the backarc (southern Tyrrhenian margin). Both basins affect the collisional chain (Maghrebian thrust belt). An eastward progression of extension, from lower Pliocene to lower Pleistocene, based on different onset of the basin fill, has been documented in the Southern Tyrrhenian margin. The study area represents the meeting place of backarc and foreland rifting that affected the late Miocene thrust belt. The recognized pattern of extensional deformation of the upper plate adds some constraint on the geodynamic evolution of the African and Eurasia plates and supports a model of westward dipping slab in the Central Mediterranean. It is hypothesized that the along-trench variation of the nature of the plates, due to paleo-margin configuration, has a profound impact on the upper crustal deformation during the convergence and thus the meeting place of backarc and foreland rifting could represent the surficial signature of the slab detachment since Pliocene times.

We study pneumatically inflated membranes indented by rigid indenters of different sizes and shapes. When the volume of the inflated membrane is beyond a critical value, a symmetric deformation mode becomes unstable and the system follows a path of asymmetric deformation. This bifurcation is analysed analytically for a two-dimensional membrane with either a line or plane indenter for which the stable deformation path is determined by computing the total system potential energy of different configurations. An axisymmetric membrane with indenters of different shapes and sizes is further investigated numerically. In this case, a cylindrical indenter can always trigger bifurcation while a small spherical indenter tends to be encapsulated rather than induce an asymmetric deformation mode. This result suggests that the observed bifurcation behaviour can be actively tuned and even triggered selectively by tuning indenter shape and size. We also demonstrate the effects of friction and biased bifurcation analytically through the example of a two-dimensional membrane with a line indenter.

The Eastern Tyrrhenian margin (ETM), the active boundary of the Tyrrhenian Sea backarc basin, is the key for understanding the geodynamics of the central Mediterranean. Numerous seismic tomography studies have been carried out in this region, proposing different reconstructions of the lower subducting plate and cause of the slab-break-off existing beneath the Southern Apennines. However, the area and mode of the recent deformation of the Tyrrhenian Sea are still not fully defined and understood. In this study, we combine the analysis of a recent seismic tomography model and geological data, in order to understand the relationship between the subducting lower plate and the tectonic evolution of the sedimentary basins formed on the upper plate. With this aim, we interpreted a large data set of seismic reflection profiles and several well logs. The results consist in 2D and 3D geological models of the basins, sedimentary infill, and fault networks. Taking into account the geological data of the ETM and those of the adjacent inner flank of the Apennines, we observe: (i) a system of linked sedimentary basins developed on a narrow deformation belt bounded by transform fault zones; (ii) a polyphase rifting within the upper plate; (iii) an abrupt change of the direction of extension (~ 90°), from NE-oriented in the Lower Pleistocene to SE-oriented in the Middle Pleistocene. Since these ETM features are not the typical expressions of the current backarc extensional models, we propose a link between the evolution of upper plate and the onset and development of a STEP (Subduction-Transform-Edge-Propagator) fault along the northern margin of the Ionian slab.