Surface deformations and gravity changes caused by pressurized finite ellipsoidal cavities

We develop quasi-analytical solutions for the surface deformation field and gravity changes due to the pressurization of a finite (triaxial) ellipsoidal cavity in a half-space. The solution is in the form of a non-uniform distribution of triaxial point sources within the cavity. The point sources have the same aspect ratio, determined by the cavity shape, while their strengths and spacing are determined in an adaptive manner, such that the net point-source potency per unit volume is uniform. We validate and compare our solution with analytical and numerical solutions. We provide computationally efficient MATLAB codes tailored for source inversions. This solution opens the possibility of exploring the geometry of shallow magma chambers for potential deviations from axial symmetry

Retinal photoisomerization versus counterion protonation in light and dark-adapted bacteriorhodopsin and its primary photoproduct

Discovered over 50 years ago, bacteriorhodopsin is the first recognized and most widely studied microbial retinal protein. Serving as a light-activated proton pump, it represents the archetypal ion-pumping system. Here we compare the photochemical dynamics of bacteriorhodopsin light and dark-adapted forms with that of the first metastable photocycle intermediate known as “K”. We observe that following thermal double isomerization of retinal in the dark from bio-active all-trans 15-anti to 13-cis, 15-syn, photochemistry proceeds even faster than the ~0.5 ps decay of the former, exhibiting ballistic wave packet curve crossing to the ground state. In contrast, photoexcitation of K containing a 13-cis, 15-anti chromophore leads to markedly multi-exponential excited state decay including much slower stages. QM/MM calculations, aimed to interpret these results, highlight the crucial role of protonation, showing that the classic quadrupole counterion model poorly reproduces spectral data and dynamics. Single protonation of ASP212 rectifies discrepancies and predicts triple ground state structural heterogeneity aligning with experimental observations. These findings prompt a reevaluation of counter ion protonation in bacteriorhodopsin and contribute to the broader understanding of its photochemical dynamics

Spectroscopic fingerprints of DNA/RNA pyrimidine nucleobases in third-order nonlinear electronic spectra

Accurate ab initio modeling of spectroscopic signals in nonlinear electronic spectra, such as bidimensional (2D) spectra, requires the computation of the electronic transitions induced by the incoming pump/probe pulses, resulting in a challenging calculation of many electronic excited states. A protocol is thus required to evaluate the variations of spectral properties, like transition energies and dipole moments, with the computational level, and to estimate the sensitivity of the spectra to these variations. Such a protocol is presented here within the framework of complete and restricted active space self-consistent field (CASSCF/RASSCF) theory and its second-order perturbation theory extensions (CASPT2/RASPT2). The electronic excited-state manifolds of pyrimidine nucleobases (thymine, uracil, and cytosine) are carefully characterized in vacuo employing high-level RAS(0,0|10,8|2,12)//SS-RASPT2 calculations. The results provide a reference data set that can be used for optimizing computational efforts and costs, as required for studying computationally more demanding multichromophoric systems (e.g., di- and oligonucleotides). The spectroscopic signatures of the 2D electronic spectrum of a perfectly stacked uracil–cytosine dimer model are characterized, and experimental setups are proposed that can resolve non-covalent interchromophoric interactions in canonical pyrimidine nucleobase-stacked dimers

Integrated receivers with bottom subcooling for automotive air conditioning: detailed experimental study of their filling capacity

The use of the integrated receiver in condensers for common automotive air conditioning - A/C - systems is widespread, because of its thermodynamic and operational advantages. Many studies have been already conducted on estimating the effect of the subcooling value. However, this study aims at determining the most important factors affecting the length of the refrigerant stable operating plateau and how the receiver filling is affected by geometrical and thermodynamic boundary conditions, by means of an experimental campaign built using design of experiments - DOE - techniques. Results demonstrate how the receiver diameter and the axle spacing between its inlet and outlet holes have the highest influence on the receiver operation. Finally, these results have been used to set up a numerical model able to accurately estimate the filling efficiency of the integrated receiver, in terms of volume of the operating plateau compared to the net available receiver volume

Simulating Plasmon Resonances of Gold Nanoparticles with Bipyramidal Shapes by Boundary Element Methods

Computational modeling and accurate simulations of localized surface plasmon resonance (LSPR) absorption properties are reported for gold nanobipyramids (GNBs), a class of metal nanoparticle that features highly tunable, geometry-dependent optical properties. GNB bicone models with spherical tips performed best in reproducing experimental LSPR spectra while the comparison with other geometrical models provided a fundamental understanding of base shapes and tip effects on the optical properties of GNBs. Our results demonstrated the importance of averaging all geometrical parameters determined from transmission electron microscopy images to build representative models of GNBs. By assessing the performances of LSPR absorption spectra simulations based on a quasi-static approximation, we provided an applicability range of this approach as a function of the nanoparticle size, paving the way to the theoretical study of the coupling between molecular electron densities and metal nanoparticles in GNB-based nanohybrid systems, with potential applications in the design of nanomaterials for bioimaging, optics and photocatalysis

Drainage of a deep magma reservoir near Mayotte inferred from seismicity and deformation

The dynamics of magma deep in the Earth’s crust are difficult to capture by geophysical monitoring. Since May 2018, a seismically quiet area offshore of Mayotte in the western Indian Ocean has been affected by complex seismic activity, including long-duration, very-long-period signals detected globally. Global Navigation Satellite System stations on Mayotte have also recorded a large surface deflation offshore. Here we analyse regional and global seismic and deformation data to provide a one-year-long detailed picture of a deep, rare magmatic process. We identify about 7,000 volcano-tectonic earthquakes and 407 very-long-period seismic signals. Early earthquakes migrated upward in response to a magmatic dyke propagating from Moho depth to the surface, whereas later events marked the progressive failure of the roof of a magma reservoir, triggering its resonance. An analysis of the very-long-period seismicity and deformation suggests that at least 1.3 km3 of magma drained from a reservoir of 10 to 15 km diameter at 25 to 35 km depth. We demonstrate that such deep offshore magmatic activity can be captured without any on-site monitoring

Investigating the Origin of Seismic Swarms

According to the U.S. Geological Survey’s Earthquake Hazards Program, a seismic swarm is “a localized surge of earth- quakes, with no one shock being conspicuously larger than all other shocks of the swarm. They might occur in a variety of geologic environments and are not known to be indicative of any change in the long- term seismic risk of the region in which they occur” (http://vulcan.wr.usgs.gov/Glossary/ Seismicitydescription_earthquakes.html). The definition reveals how little is actually known about seismic swarms. For example, could certain seismic settings be more prone to swarms? Could a fault zone prone to large energetic earthquakes release part of its stress through seismic swarms? Do swarms keep hazards in balance, or could their onset increase hazards? To gain insight into the nature of seismic swarms in nonvolcanic areas and to better understand their influence on seismic hazards, the Istituto Nazionale di Geofisica e Vulcanologia (INGV) and the German Research Centre for Geoscience (GFZ) began a combined research project within the framework of the Network of European Research Infrastructures for Earthquake Risk Assessment and Mitigation (NERA; see http:// www.nera-eu.org/). The project focused on monitoring swarm activity occurring in the Pollino range in Southern Apennines, Italy.Published361-3721.1. TTC - Monitoraggio sismico del territorio nazionaleN/A or not JCRrestricte

Tailored treatments in inborn errors of immunity associated with atopy (IEIs-A) with skin involvement

inborn errors of immunity associated with atopy (IEIs-A) are a group of inherited monogenic disorders that occur with immune dysregulation and frequent skin involvement. several pathways are involved in the pathogenesis of these conditions, including immune system defects, alterations of skin barrier and metabolism perturbations. current technological improvements and the higher accessibility to genetic testing, recently allowed the identification of novel molecular pathways involved in IEIs-A, also informing on potential tailored therapeutic strategies. compared to other systemic therapy for skin diseases, biologics have the less toxic and the best tolerated profile in the setting of immune dysregulation. Here, we review IEIs-A with skin involvement focusing on the tailored therapeutic approach according to their pathogenetic mechanism

Impact Forecasting to Support Emergency Management of Natural Hazards

Forecasting and early warning systems are important investments to protect lives, properties, and livelihood. While early warning systems are frequently used to predict the magnitude, location, and timing of potentially damaging events, these systems rarely provide impact estimates, such as the expected amount and distribution of physical damage, human consequences, disruption of services, or financial loss. Complementing early warning systems with impact forecasts has a twofold advantage: It would provide decision makers with richer information to take informed decisions about emergency measures and focus the attention of different disciplines on a common target. This would allow capitalizing on synergies between different disciplines and boosting the development of multihazard early warning systems. This review discusses the state of the art in impact forecasting for a wide range of natural hazards. We outline the added value of impact-based warnings compared to hazard forecasting for the emergency phase, indicate challenges and pitfalls, and synthesize the review results across hazard types most relevant for Europe

Cyclical geothermal unrest as a precursor to Iceland’s 2021 Fagradalsfjall eruption

Understanding and constraining the source of geodetic deformation in volcanic areas is an important component of hazard assessment. Here, we analyse deformation and seismicity for one year before the March 2021 Fagradalsfjall eruption in Iceland. We generate a high-resolution catalogue of 39,500 earthquakes using optical cable recordings and develop a poroelastic model to describe three pre-eruptional uplift and subsidence cycles at the Svartsengi geothermal field, 8 km west of the eruption site. We find the observed deformation is best explained by cyclic intrusions into a permeable aquifer by a fluid injected at 4 km depth below the geothermal field, with a total volume of 0.11 ± 0.05 km3 and a density of 850 ± 350 kg m–3. We therefore suggest that ingression of magmatic CO2 can explain the geodetic, gravity and seismic data, although some contribution of magma cannot be excluded