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  • Articles  (327,125)
  • American Physical Society  (192,063)
  • Oxford University Press  (135,062)
  • 2020-2024  (570)
  • 2010-2014  (176,358)
  • 1990-1994  (77,949)
  • 1985-1989  (61,779)
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  • 1
    Publication Date: 2024-04-09
    Description: Serpentinites are polymineralic rocks distributed almost ubiquitously across the globe in active tectonic regions. Magnetite-rich serpentinites are found in the low-strain domains of serpen- tinite shear zones, which act as potential sites of nucleation of unstable slip. To assess the potential of earthquake nucleation in these materials, we investigate the link between me- chanical properties and fabric of these rocks through a suite of laboratory shear experiments. Our experiments were done at room temperature and cover a range of normal stress and slip velocity from 25 to 100 MPa and 0.3 to 300 μm s −1 , respecti vel y. We show that magnetite-rich serpentinites are ideal materials since they display strong sensitivity to the loading rate and are susceptible to nucleation of unstable slip, especially at low forcing slip velocities. We also aim at the integration of mechanical and microstructural results to describe the underlying mechanisms that produce the macroscopic behaviour. We show that mineralogical composi- tion and mineral structure dictates the coexistence of two deformation mechanisms leading to stable and unstable slip. The weakness of phyllosilicates allows for creep during the interseis- mic phase of the laboratory seismic cycle while favouring the restoration of a load-bearing granular framework, responsible of the nucleation of unstable events. During dynamic slip, fault zone shear fabric determines the mode of slip, producing either asymmetric or Gaussian slip time functions for either fast or slow events. We report rate/state friction parameters and integrate our mechanical data with microstructural observations to shed light on the mech- anisms dictating the complexity of laborator y ear thquakes. We show that mineralogical and fabric heterogeneities control fault slip behaviour.
    Description: Published
    Description: 1778–1797
    Description: OST3 Vicino alla faglia
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 2
    Publication Date: 2024-04-30
    Description: Current understanding of the kinetic-scale turbulence in weakly collisional plasmas still remains elusive. We employ a general framework in which the turbulent energy transfer is envisioned as a scale-to-scale Langevin process. Fluctuations in the sub-ion range show a global scale invariance, thus suggesting a homogeneous energy repartition. In this Letter, we interpret such a feature by linking the drift term of the Langevin equation to scaling properties of fluctuations. Theoretical expectations are verified on solar wind observations and numerical simulations, thus giving relevance to the proposed framework for understanding kinetic-scale turbulence in space plasmas.
    Description: Published
    Description: L042014
    Description: OSA3: Climatologia e meteorologia spaziale
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 3
    Publication Date: 2024-01-19
    Description: We performed seismic ambient noise tomography to investigate the shallow crustal structure around the Ivrea geophysical body (IGB) in the Ivrea-Verbano Zone (IVZ). We achieved higher resolution with respect to previous tomographic works covering the Western Alps, by processing seismic data collected by both permanent and temporary seismic networks (61 broad-band seismic stations in total). This included IvreaArray, a temporary, passive seismic experiment designed to investigate the IVZ crustal structure. Starting from continuous seismic ambient noise recordings, we measured and inverted the dispersion of the group velocity of surface Rayleigh waves (fundamental mode) in the period range 4–25 s. We obtained a new, 3-D vS model of the IVZ crust via the stochastic neighbourhood algorithm (NA), with the highest resolution between 3 to 40 km depth. The fast and shallow shear wave velocity anomaly associated with the IGB presents velocities of 3.6 km s−1 directly at the surface, in remarkable agreement with the location of the exposed lower-to-middle crustal and mantle outcrops. This suggests a continuity between the surface geological observations and the subsurface geophysical anomalies. The fast IGB structure reaches vS of 4 km s−1 at 20–25 km depth, at the boundary between the European and Adriatic tectonic plates, and in correspondence with the earlier identified Moho jump in the same area. The interpretation of a very shallow reaching IGB is further supported by the comparison of our new results with recent geophysical investigations, based on receiver functions and gravity anomaly data. By combining the new geophysical constraints and the geological observations at the surface, we provide a new structural interpretation of the IGB, which features lower crustal and mantle rocks at upper crustal depths. The comparison of the obtained vS values with the physical properties from laboratory analysis of local rock samples suggests that the bulk of the IGB consists of a combination of mantle peridotite, ultramafic and lower crustal rocks, bound in a heterogeneous structure. These new findings, based on vS tomography, corroborate the recent interpretation for which the Balmuccia peridotite outcrops are continuously linked to the IGB structure beneath. The new outcomes contribute to a multidisciplinary framework for the interpretation of the forthcoming results of the scientific drilling project DIVE. DIVE aims at probing the lower continental crust and its transition to the mantle, with two ongoing and one future boreholes (down to 4 km depth) in the IVZ area, providing new, complementary information on rock structure and composition across scales. In this framework, we constrain the upper crustal IGB geometries and lithology based on new evidence for vS, connecting prior crustal knowledge to recent active seismic investigations.
    Description: Published
    Description: 1089–1105
    Description: OST1 Alla ricerca dei Motori Geodinamici
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 4
    Publication Date: 2024-01-23
    Description: On the 9th of January 2020, an Mw 6.4 strike-slip earthquake took place north of the Asian margin of the Bering Sea. The earthquake occurred within the known reverse-right-lateral active fault zone, called Khatyrka–Vyvenka, which transverses the Koryak Highland from SE to NW and is thought to be a surface manifestation of the Asian portion of either the Bering plate boundary or the northern edge of the Alaskan stream. No other strong earthquake has ever been recorded in this remote uninhabited area and the few existing seismic stations provide poor quality earthquake locations.We adopt SAR interferometry (InSAR) technique to define an improved location of the Koryak 2020 earthquake and constrain the seismic source. The analysis of the 2020 event revealed a previously unknown active fault of left-lateral kinematics that is possibly hidden and strikes NWtransversely to the Khatyrka–Vyvenka fault zone. Although several mechanisms could account for left-lateral kinematics of this fault, we propose that the structure is part of a more extended NW fault structure, that formed in pre-neotectonic times and has played a role of a pre-existing rheological discontinuity. This revived NW structure together with a similar structure located easterly, so far aseismic, make the plate/stream boundary segmented, step-like in plan view. The step-like boundary geometry may be the result of internal transform deformation of a rigid plate, but it is better explained by deflections of the Alaskan stream edge at local crustal asperities, which are pre-Cenozoic terrains.
    Description: Published
    Description: 1412–1421
    Description: OST2 Deformazione e Hazard sismico e da maremoto
    Description: JCR Journal
    Keywords: Plate motion ; Radar interferometry ; Seismic cycle ; Asia
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 5
    Publication Date: 2024-03-19
    Description: Accurate quantification of seismic activity in volcanic regions is an important asset for im- proving hazard and risk assessment. This is especially true for densely populated areas, as in the case of Etna volcano (Southern Italy). There, the volcanic hazard is amplified by the seismic risk of acti ve faults, especiall y on the eastern flank of the volcano. In such a context, it is common to rely on moment magnitude ( M W ) to characterize seismicity and monitor the energy released during an eruption. In this study, we calculate the moment-based magnitude ( M W ) for selected seismic data sets, using different approaches in distinct magnitude ranges to cover the widest possible range of magnitude that characterizes Etna’s seismicity . Specifically , we computed the M W from a data set of moment tensor solutions of earthquakes that occurred in the magnitude range 3.4 ≤M L ≤4.8 during 2005–2020; we created a data set of seismic moment and associated M W for earthquakes 1.0 ≤M L 〈 3.4 obtained by analysing source spectra; we fine-tuned two relationships, for shallow and deep earthquakes, to obtain M W from response spectra. Finally, we calibrated a specific relationship between M W and M L for the Etna area earthquakes in the range 1.0 ≤M L ≤4.8. All the empirical relationships obtained in this study can be applied in real-time analysis of the seismicity to provide fast and robust information on the released seismic energy.
    Description: INGV-DPC 2012- 2021 agreement; B2 DPC-INGV 2019-2021 project; IMPACT Department strategic project ; ‘Project PE0000005–RETURN (NRRP)
    Description: Published
    Description: 2520-2534
    Description: OST2 Deformazione e Hazard sismico e da maremoto
    Description: JCR Journal
    Keywords: Earthquak e source observations ; Earthquake hazards ; Time series analysis ; Full moment tensor
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 6
    Publication Date: 2024-03-12
    Description: This study presents a new robust statistical framework, in which to measure relative differences, or deviations from a hypothetical reference value, of Gutenberg-Richter b-value. Moreover, it applies this method to recent seismicity in Italy, to find possible changes of earthquake magnitude distribution in time and space. The method uses bootstrap techniques, which have no prior assumptions about the distribution of data, keeping their basic features. Excluding Central Italy, no significative b-value variation is found, revealing that the frequency-magnitude distribution exponent is substantially stable or that data are not able to reveal hidden variations. Considering the small size of examined magnitude samples, we cannot definitively decide if the higher b-values in Central Italy, consistently founded by all applied tests, have a physical origin or result from a statistical bias. In any case, they indicate short-lived excursions which have a temporary nature and, therefore, cannot be associated solely to spatial variations in tectonic framework. Both the methodological issues and the results of the application to seismicity in Italy show that a correct assessing of b-value changes requests appropriate statistics, that accurately quantify the low accuracy and precision of b-value estimation for small magnitude samples.
    Description: Published
    Description: 729–740
    Description: OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impatto
    Description: JCR Journal
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  • 7
    Publication Date: 2024-03-12
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: We present the results from a fully unconstrained moment tensor inversion of induced seismic events in a complex and high seismic hazard region (Val d’Agri basin, Southern Italy). The study area hosts two well-documented cases of induced microseismicity linked to (i) a wastewater injection well of a giant oilfield (the largest in onshore Europe), and (ii) severe seasonal level changes of an artificial lake. In order to gather information on the non-doublecouple components of the source and to better understand the rupture mechanisms, we analyse seismic events recorded during daily injection tests in the disposal well. The computed moment tensors have significant non-double-couple components that correlate with the well-head injection pressure. The injection parameters strongly influence the rupture mechanism that can be interpreted as due to the opening/closing of a fracture network inside a fault zone of a pre-existing thrust fault. For the case of the reservoir-induced seismicity, no direct correlations are observed with the loading/unloading of the reservoir.
    Description: Published
    Description: 1617–1627
    Description: OST3 Vicino alla faglia
    Description: JCR Journal
    Keywords: 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 8
    Publication Date: 2024-04-03
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: Estimation of local seismic response plays a key role in assessing local seismic hazard and particularly in the design of shaking scenarios. Modelling local seismic response involves knowing of the shear wave velocity (Vs) and quality factor (Qs) profiles for the site in question. The many techniques that have been developed to assess Vs in surface deposits produce reliable measurements of Vs , but these rarely correspond to direct measurements of Qs . The latter is often considered through damping measures from laboratory tests on small-scale soil samples, which can provide information primarily on intrinsic attenuation, neglecting the contribution of scattering effects. In this paper, using seismic recordings obtained at the surface and in boreholes at 100 m depth, we estimate an average value of Qs of some characteristic alluvial deposits of the Po Plain (northern Italy). Data come from a microseismic network which sampled an almost uniform lithology in the central Po Plain and consisted of three surface and four borehole stations with an interstation distance of about 2 km. The average value of Qs of the shallowest 100 m of the sedimentary strata, Qs100, is estimated by considering: (1) the high-frequency attenuation of seismic waves due to propagation through the corresponding stratigraphy and (2) the interference between incident and surface-reflected waves observed at borehole stations. We parametrize the first through k0_100, the difference between the values of the spectral decay parameter kappa (k) estimated at the surface and at the boreholes depth, respectively. We use the second in order to compute Vs100, the time-averaged Vs referred to the uppermost 100 m stratigraphy. We obtain: k0_100 = (11 ± 3) ms, Vs100 = (309 ± 11) m s −1 and Qs100 = 31 ± 10. At the surface, the estimated values of the site-specific kappa, k0, are found to range from 75 to 79 ms. As expected, these results are in good agreement with studies performed in other sites characterized by sandy or clayey lithologies, and can be usefully used in site response analysis at sites where the rigidity is mainly controlled by lithostatic pressure.
    Description: Comune di Minerbio (grant: “Sperimentazione ILG Minerbio”; grant number: 0913.010).
    Description: Published
    Description: 2075–2094
    Description: OST2 Deformazione e Hazard sismico e da maremoto
    Description: JCR Journal
    Keywords: Earthquake ground motions ; Seismic attenuation ; Site effects ; Wave propagation ; Wave scattering and diffraction ; 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 9
    Publication Date: 2024-05-09
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: In a recent work, we applied the every earthquake a precursor according to scale (EEPAS) probabilistic model to the pseudo-prospective forecasting of shallow earthquakes with magni- tude M 5.0 in the Italian region. We compared the forecasting performance of EEPAS with that of the epidemic type aftershock sequences (ETAS) forecasting model, using the most recent consistency tests developed within the collaboratory for the study of earthquake predictabil- ity (CSEP). The application of such models for the forecasting of Italian target earthquakes seems to show peculiar characteristics for each of them. In particular, the ETAS model showed higher performance for short-term forecasting, in contrast, the EEPAS model showed higher forecasting performance for the medium/long-term. In this work, we compare the performance of EEPAS and ETAS models with that obtained by a deterministic model based on the occur- rence of strong foreshocks (FORE model) using an alarm-based approach. We apply the two rate-based models (ETAS and EEPAS) estimating the best probability threshold above which we issue an alarm. The model parameters and probability thresholds for issuing the alarms are calibrated on a learning data set from 1990 to 2011 during which 27 target earthquakes have occurred within the analysis region. The pseudo-prospective forecasting performance is as- sessed on a validation data set from 2012 to 2021, which also comprises 27 target earthquakes. Tests to assess the forecasting capability demonstrate that, even if all models outperform a purely random method, which trivially forecast earthquake proportionally to the space–time occupied by alarms, the EEPAS model exhibits lower forecasting performance than ETAS and FORE models. In addition, the relative performance comparison of the three models demonstrates that the forecasting capability of the FORE model appears slightly better than ETAS, but the difference is not statistically significant as it remains within the uncertainty level. However, truly prospective tests are necessary to validate such results, ideally using new testing procedures allowing the analysis of alarm-based models, not yet available within the CSEP.
    Description: Published
    Description: 1541–1551
    Description: OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impatto
    Description: JCR Journal
    Keywords: Computational seismology ; Earthquake interaction, forecasting and prediction ; Statistical seismology ; Comparison betwee earthquake forecasting methods
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 10
    Publication Date: 2024-05-09
    Description: To understand the seismic hazard of a subduction zone, it is necessary to know the geometry, location and mechanical characteristics of the interplate boundary below which an oceanic plate is thrust downward. By considering the azimuthal dependence of converted P-to-S (Ps) amplitudes in receiver functions, we have detected the interplate boundary in the Makran subduction zone, revealing significant seismic anisotropy at the base of the accretionary wedge above the slab before it bends down beneath the Jaz Murian basin. This anisotropic feature aligns with a zone of reduced seismic velocity and a high primary/secondary wave velocity ratio (Vp/Vs), as documented in previous studies. The presence of this low-velocity highly anisotropic layer at the base of the accretionary wedge, likely representing a low-strength shear zone, could possibly explain the unusually wide accretionary wedge in Makran. Additionally, it may impact the location and width of the locked zone along the interplate boundary.
    Description: Iranian National Science Foundation (INSF)
    Description: Published
    Description: 64-74
    Description: OST1 Alla ricerca dei Motori Geodinamici
    Description: JCR Journal
    Keywords: Earthquake hazards, Seismic anisotropy, Crustal structure, Subduction zone processes ; 04.06. Seismology
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  • 11
    Publication Date: 2024-05-09
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: The Every Earthquake a Precursor According to Scale (EEPAS) forecasting model is a space– time point-process model based on the precursory scale increase (ψ ) phenomenon and associated predictive scaling relations. It has been previously applied to New Zealand, Cal- ifornia and Japan earthquakes with target magnitude thresholds varying from about 5–7. In all previous application, computations were done using the computer code implemented in Fortran language by the model authors. In this work, we applied it to Italy using a suite of computing codes completely rewritten in Matlab. We first compared the two software codes to ensure the convergence and adequate coincidence between the estimated model parameters for a simple region capable of being analysed by both software codes. Then, using the rewritten codes, we optimized the parameters for a different and more complex polygon of analysis using the Homogenized Instrumental Seismic Catalogue data from 1990 to 2011. We then perform a pseudo-prospective forecasting experiment of Italian earthquakes from 2012 to 2021 with Mw ≥ 5.0 and compare the forecasting skill of EEPAS with those obtained by other time in- dependent (Spatially Uniform Poisson, Spatially Variable Poisson and PPE: Proximity to Past Earthquakes) and time dependent [Epidemic Type Aftershock Sequence (ETAS)] forecasting models using the information gain per active cell. The preference goes to the ETAS model for short time intervals (3 months) and to the EEPAS model for longer time intervals (6 months to 10 yr).
    Description: Published
    Description: 1681–1700
    Description: OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impatto
    Description: JCR Journal
    Keywords: Computational seismology ; Earthquake interaction ; forecasting and prediction ; Statistical seismology ; Earthquake forecasting
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 12
    Publication Date: 2024-05-27
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: We report on about 20 yr of relative gravity measurements, acquired on Mt. Somma–Vesuvius volcano in order to investigate the hydrological and volcano-tectonic processes controlling the present-day activity of the volcano. The retrieved long-term field of time gravity change (2003–2022) shows a pattern essentially related to the subsidence, which have affected the central part of the volcano, as detected by the permanent GNSS network and InSAR data. After reducing the observations for the effect of vertical deformation, no significant residuals are found, indicating no significant mass accumulation or loss within the volcanic system. In the north-western sector of the study area, at the border of the volcano edifice, however, significant residual positive gravity changes are detected which are associated to ground-water rebound after years of intense exploitation of the aquifers. On the seasonal timescale, we find that stations within the caldera rim are affected by the seasonal hydrological effects, while the gravity stations at the base of the Vesuvius show a less clear correlation. Furthermore, within the caldera rim a multiyear gravity transient is detected with an increase phase lasting about 4 yr followed by a slower decrease phase. Analysis of rain data seem to exclude a hydrological origin, hence, we hypothesize a deeper source related to the geothermal activity, which can be present even if the volcano is in a quiescent state. We infer the depth and volume of the source by inverting the spatial pattern of the gravity field at the peak of the transient. A volume of fluids of 9.5 × 107 m3 with density of 1000 kg m−3 at 2.3 km depth is capable to fit reasonably well the observations. To explain the gravity transient, simple synthetic models are produced, that simulate the ascent of fluids from a deep reservoir up to the depth of 2.3 km and a successive diffusion within the carbonate aquifer hosting the geothermal system. The whole process appears to not significantly affect the seismicity rate and the deformation of the volcano. This study demonstrates the importance of a 4-D gravity monitoring of a volcano to understand its complex gravity signals that cover different spatial and temporal scales. Discriminating the different contributions that mix up in the observed gravity changes, in particular those due to hydrologic/anthropogenic activities form those due to the geothermal dynamics, is fundamental for a complete and reliable evaluation of the volcano state.
    Description: Published
    Description: 1565–1580
    Description: OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametrici
    Description: JCR Journal
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  • 13
    Publication Date: 2024-06-17
    Description: Thermobarometry provides a critical means of assessing locations of magma storage and dynamics in the lead-up to volcanic eruptions and crustal growth. A common approach is to utilise minerals that have compositions sensitive to changes in pressure and/or temperature, such as clinopyroxene, which is ubiquitous in mafic to intermediate magmas. However, clinopyroxene thermobarometry may carry significant uncertainty and require an appropriate equilibrium melt composition. In addition, the degree of magma undercooling (ΔT) affects clinopyroxene composition and zoning, with common sector zoning potentially obfuscating thermobarometry results. Here, we use a set of crystallisation experiments on a primitive trachybasalt from Mt. Etna (Italy) at ΔT = 25–233 °C, P = 400–800 MPa, H2O = 0–4 wt % and fO2 = NNO + 2, with clinopyroxene crystals defined by Al-rich zones (prisms and skeletons) and Al-poor zones (hourglass and overgrowths) to assess common equilibrium models and thermobarometric approaches. Under the studied conditions, our data suggest that the commonly applied Fe–Mg exchange (cpx-meltKdFe–Mg) is insensitive to increasing ΔT and may not be a reliable indicator of equilibrium. The combined use of DiHd (CaMgSi2O6 + CaFeSi2O6) and EnFs (Mg2Si2O6 + Fe2Si2O6) models indicate the attainment of equilibrium in both Al-rich and Al-poor zones for almost all investigated ΔT. In contrast, CaTs (CaAl2SiO6) and CaTi (CaTiAl2O6) models reveal substantial deviations from equilibrium with increasing ΔT, particularly in Al-rich zones. We postulate that this reflects slower diffusion of Al and Ti in the melt compared with Ca and Mg and recommend the concurrent application of these four models to evaluate equilibrium between clinopyroxene and melt, particularly for sector-zoned crystals. Thermobarometers calibrated with only isothermal–isobaric experiments closely reproduce experimental P–T at low ΔT, equivalent to natural phenocrysts cores and sector-zoned mantles. Models that also consider decompression experiments are most accurate at high ΔT and are therefore suitable for outermost phenocryst rims and groundmass microlites. Recent machine learning approaches reproduce P–T conditions across all ΔT conditions. Applying our experimental constraints to sector-zoned microphenocrysts and groundmass microlites erupted during the 1974 eccentric eruption at Mt. Etna, we highlight that both hourglass and prism sectors are suitable for thermobarometry, given that equilibrium is sufficiently tested for. The combination of DiHd, EnFs, CaTs and CaTi models identifies compositions closest to equilibrium with the bulk melt composition, and results in smaller differences in P–T calculated for hourglass and prism sectors compared with applying only DiHd and EnFs equilibrium models. This provides a framework to assess crystallisation conditions recorded by sector-zoned clinopyroxene crystals in mafic alkaline settings.
    Description: Published
    Description: egad074
    Description: OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametrici
    Description: JCR Journal
    Keywords: Experimental Petrology ; Petrology ; Clinopyroxene ; Thermobarometry ; Experimental Petrology
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  • 14
    Publication Date: 2024-07-02
    Description: The joint ESA/NASA Mass-change And Geosciences International Constellation (MAGIC) has the objective to extend time-series from previous gravity missions, including an improvement of accuracy and spatio-temporal resolution. The long-term monitoring of Earth’s gravity field carries information on mass change induced by water cycle, climate change and mass transport processes between atmosphere, cryosphere, oceans and solid Earth. MAGIC will be composed of two satellite pairs flying in different orbit planes. The NASA/DLR-led first pair (P1) is expected to be in a near-polar orbit around 500 km of altitude; while the second ESA-led pair (P2) is expected to be in an inclined orbit of 65°–70° at approximately 400 km altitude. The ESA-led pair P2 Next Generation Gravity Mission shall be launched after P1 in a staggered manner to form the MAGIC constellation. The addition of an inclined pair shall lead to reduction of temporal aliasing effects and consequently of reliance on de-aliasing models and post-processing. The main novelty of the MAGIC constellation is the delivery of mass-change products at higher spatial resolution, temporal (i.e. subweekly) resolution, shorter latency and higher accuracy than the Gravity Recovery and Climate Experiment (GRACE) and Gravity Recovery and Climate Experiment Follow-On (GRACE-FO). This will pave the way to new science applications and operational services. In this paper, an overview of various fields of science and service applications for hydrology, cryosphere, oceanography, solid Earth, climate change and geodesy is provided. These thematic fields and newly enabled applications and services were analysed in the frame of the initial ESA Science Support activities for MAGIC. The analyses of MAGIC scenarios for different application areas in the field of geosciences confirmed that the double-pair configuration will significantly enlarge the number of observable mass-change phenomena by resolving smaller spatial scales with an uncertainty that satisfies evolved user requirements expressed by international bodies such as IUGG. The required uncertainty levels of dedicated thematic fields met by MAGIC unfiltered Level-2 products will benefit hydrological applications by recovering more than 90 per cent of the major river basins worldwide at 260 km spatial resolution, cryosphere applications by enabling mass change signal separation in the interior of Greenland from those in the coastal zones and by resolving small-scale mass variability in challenging regions such as the Antarctic Peninsula, oceanography applications by monitoring meridional overturning circulation changes on timescales of years and decades, climate applications by detecting amplitude and phase changes of Terrestrial Water Storage after 30 yr in 64 and 56 per cent of the global land areas and solid Earth applications by lowering the Earthquake detection threshold from magnitude 8.8 to magnitude 7.4 with spatial resolution increased to 333 km.
    Description: Published
    Description: 1288–1308
    Description: JCR Journal
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  • 15
    Publication Date: 2023-02-22
    Description: 7 Figures, 20 pages
    Description: The search of hardware-compatible strategies for solving NP-hard combinatorial optimization problems (COPs) is an important challenge of today s computing research because of their wide range of applications in real world optimization problems. Here, we introduce an unconventional scalable approach to face maximum satisfiability problems (Max-SAT) which combines probabilistic computing with p-bits, parallel tempering, and the concept of invertible logic gates. We theoretically show the spintronic implementation of this approach based on a coupled set of Landau-Lifshitz-Gilbert equations, showing a potential path for energy efficient and very fast (p-bits exhibiting ns time scale switching) architecture for the solution of COPs. The algorithm is benchmarked with hard Max-SAT instances from the 2016 Max-SAT competition (e.g., HG-4SAT-V150-C1350-1.cnf which can be described with 2851 p-bits), including weighted Max-SAT and Max-Cut problems.
    Description: Published
    Description: 024052
    Description: 3IT. Calcolo scientifico
    Description: JCR Journal
    Keywords: Physics - Mesoscopic Systems and Quantum Hall Effect; Physics - Mesoscopic Systems and Quantum Hall Effect
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  • 16
    Publication Date: 2023-02-25
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Hudson, A. R., Peters, D. P. C., Blair, J. M., Childers, D. L., Doran, P. T., Geil, K., Gooseff, M., Gross, K. L., Haddad, N. M., Pastore, M. A., Rudgers, J. A., Sala, O., Seabloom, E. W., & Shaver, G. Cross-site comparisons of dryland ecosystem response to climate change in the US long-term ecological research network. Bioscience, 72(9), (2022): 889–907, https://doi.org/10.1093/biosci/biab134.
    Description: Long-term observations and experiments in diverse drylands reveal how ecosystems and services are responding to climate change. To develop generalities about climate change impacts at dryland sites, we compared broadscale patterns in climate and synthesized primary production responses among the eight terrestrial, nonforested sites of the United States Long-Term Ecological Research (US LTER) Network located in temperate (Southwest and Midwest) and polar (Arctic and Antarctic) regions. All sites experienced warming in recent decades, whereas drought varied regionally with multidecadal phases. Multiple years of wet or dry conditions had larger effects than single years on primary production. Droughts, floods, and wildfires altered resource availability and restructured plant communities, with greater impacts on primary production than warming alone. During severe regional droughts, air pollution from wildfire and dust events peaked. Studies at US LTER drylands over more than 40 years demonstrate reciprocal links and feedbacks among dryland ecosystems, climate-driven disturbance events, and climate change.
    Description: Funding was provided by the USDA-ARS SCINet Big Data Project (grant no. 0500–00093–001–00-D), and the National Science Foundation US LTER Program to New Mexico State University for the Jornada Basin (grant no. DEB 20–25166), Kansas State University for the Konza Prairie (grant no. DEB 2025849), the Kellogg Biological Station (grant no. DEB 1832042), Cedar Creek Ecosystem Science Reserve (grants no. DEB-1234162 and no. DEB-1831944), ARC (grant no. DEB-1637459), MCM (grant no. OPP-1637708), CAP (grant no. DEB-1832016), and SEV (grant no. DEB-1655499). Support was also provided by the Minnesota Supercomputer Institute and the University of Minnesota, Michigan State University AgBioResearch.
    Repository Name: Woods Hole Open Access Server
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  • 17
    Publication Date: 2023-01-25
    Description: The Doldrums Megatransform System (~7–8°N, Mid-Atlantic Ridge) shows a complex architecture including four intra-transform ridge segments bounded by five active transform faults. Lower crustal rocks are exposed along the Doldrums and Vernadsky transform walls that bound the northernmost intra-transform ridge segment. The recovered gabbros are characterized by variably evolved chemical compositions, ranging from olivine gabbros to gabbronorites and oxide gabbros, and lack the most primitive gabbroic endmembers (troctolites, dunites). Notably, the numerous recovered gabbronorites show up to 20 vol. % of coarse-grained orthopyroxene. Although covariations in mineral and bulk-rock chemical compositions of the olivine and oxide gabbros define trends of crystallization from a common parental melt, the gabbronorites show elevated light over heavy rare earth elements (LREE/HREE) ratios in both bulk-rock and mineral compositions. These features are not consistent with a petrological evolution driven solely by fractional crystallization, which cannot produce the preferential enrichments in highly incompatible elements documented in the orthopyroxene-bearing lithologies. We suggest that gabbronorites crystallized from evolved melts percolating and partly assimilating a pre-existing olivine gabbro matrix. Saturation in orthopyroxene and selective enrichments in LREE relative to M-HREE are both triggered by an increase in assimilated crystal mass, which ranges from negligible in the oxide-gabbros to abundant in the gabbronorites. This melt–rock reaction process has been related to lateral melt migration beneath ridge-transform intersections, where variably evolved melts injected from the peripheral parts of the melting region towards the transform zone may interact with a gabbroic crystal mush to form abundant oxide-bearing gabbronoritic associations.
    Description: Published
    Description: egac086
    Description: 3A. Geofisica marina e osservazioni multiparametriche a fondo mare
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 18
    Publication Date: 2023-02-17
    Description: Author Posting. © The Author(s), 2022. This is the author's version of the work. It is posted here by permission of Oxford University Press for personal use, not for redistribution. The definitive version was published in Geophysical Journal International 231(2),(2022): 1434–1445, https://doi.org/10.1093/gji/ggac257.
    Description: Makran subduction zone is very active with ∼38 mm yr−1 convergence rate and has experienced great earthquakes in the past. The latest great earthquake of 1945 Mw 8.1 event also triggered a large tsunami and led to ∼4000 casualties. However, due to incomplete historical seismicity records and poor modern instrumentation, earthquake mechanism, co-seismic slip and tsunami characteristics in Makran remain unclear. On 2017 February 17, an Mw 6.3 earthquake rattled offshore Pasni of Pakistan in the eastern Makran, marking the largest event after the 1945 Mw 8.1 earthquake with good geodetic and geophysical data coverage. We use a combination of seismicity, multibeam bathymetry, seismic profile, InSAR measurements and tide-gauge observation to investigate the seismogenic structure, co-seismic deformation, tsunami characteristics of this event and its implication for future major earthquakes. Our results indicate that (1) the earthquake occurred on the shallow-dipping (3°–4°) megathrust; (2) the megathrust co-seismically slipped 15 cm and caused ∼2–4 cm ground subsidence and uplift at Pasni; (3) our tsunami modelling reproduces the observed 5-cm-high small tsunami waveforms. The Pasni earthquake rupture largely overlaps the 1945 slip patch and disturbs the west and east megathrust segments that have not ruptured yet at least since 1765. With such stress perturbation and possible stress evolution effect from the 1945 earthquake, the unruptured patches may fail in the future. This study calls for more preparedness in mitigating earthquake and associated hazards in the eastern Makran.
    Description: his study is financially supported by the National Natural Science Foundation of China (Nos. 42076059, 41890813, 41976066 and 41976064), the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) (No. GML2019ZD0205), Chinese Academy of Sciences (Nos. Y4SL021001, QYZDY-SSW-DQC005, 131551KYSB20200021, ISEE2021PY03, 133244KYSB20180029 and E1SL3C02), Guangdong Basic and Applied Basic Research Foundation (No. 2021B1515020098) and China–Pakistan Joint Research Centre on Earth Sciences.
    Keywords: Tsunamis ; Earthquake dynamics ; Earthquake hazards ; Seismicity and tectonics ; Subduction zone processes
    Repository Name: Woods Hole Open Access Server
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  • 19
    Publication Date: 2023-03-15
    Description: Ground shaking, whether it is due to natural or induced earthquakes, has always been a matter of concern since it correlates with structural/non-structural damage and can culminate in human anxiety. Industrial activities such as water injection, gas sequestration and waste fluid disposals, promote induced seismicity and consequent ground shaking that can hinder ongoing activities. Therefore, keeping in mind the importance of timely evaluation of a seismic hazard and its mitigation for societal benefits, the present study proposes specifically designed ground-motion prediction equations (GMPEs) from induced earthquakes in the St. Gallen geothermal area, Switzerland. The data analysed in this study consist of 343 earthquakes with magnitude −1.17 ≤ ML, corr ≤ 3.5 and hypocentral distance between 4 and 15 km. The proposed study is one of the first to incorporate ground motions from negative magnitude earthquakes for the development of GMPEs. The GMPEs are inferred with a two-phase approach. In the first phase, a reference model is obtained by considering the effect of source and medium properties on the ground motion. In the second phase the final model is obtained by including a site/station effect. The comparison between the GMPEs obtained in the present study with GMPEs developed for the other induced seismicity environments highlights a mismatch that is ascribed to differences in regional seismic environment and local site conditions of the respective regions. This suggests that, when dealing with induced earthquakes, GMPEs specific for the study should be inferred and used for both monitoring purposes and seismic hazard analyses.
    Description: Published
    Description: 820–832
    Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 20
    Publication Date: 2023-12-27
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: The south-eastern sector of the Mount Etna, Italy, is characterized by numerous active faults, in particular the Belpasso–Ognina lineament, the Tremestieri–San Gregorio–Acitrezza fault, the Trecastagni fault and the Fiandaca–Nizzeti fault including the Timpe Fault System. Their activity is the result of both volcanism and tectonics. Here, we analyse the ground deformation occurred from 2016 to 2019 across those active faults by using the GNSS data acquired at 22 permanent stations and 35 campaign points observed by the Etna Observatory (INGV) and by the University of Catania. We also use the time-series of line of sight displacement of permanent scatterers SENTINEL-1 A-DInSAR obtained by using the P-SBAS tool of the ESA GEP-TEP (Geohazards Thematic Exploitation Platform) service. We discriminate the contributions of the regional tectonic strain, the inflations, the deflations of the volcano and the gravitational sliding in order to analyse the deformation along the faults of the south-eastern flank of Etna. The shallow and destructive Mw = 4.9 earthquake of 2018 December 26 occurred within the studied area two days after a dyke intrusion, that propagated beneath the centre of the volcano accompanied by a short eruption. Both GNSS and InSAR time-series document well those events and allow to investigate the post-seismic sliding across the faults of south-eastern flank. We analyse the slow slip events (SSE) that are observed in the GNSS and InSAR time-series in the vicinity of the Acitrezza fault. We quantify and discuss the tectonic origin of the Belpasso–Ognina lineament that we interpreted as a tear fault.
    Description: Published
    Description: 664–682
    Description: OST3 Vicino alla faglia
    Description: JCR Journal
    Keywords: Satellite geodesy ; Transient deformation ; Interferometry ; Fractures ; fault ; Volcano monitoring
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 21
    Publication Date: 2024-01-30
    Description: In the context of global warming, the melting of arctic permafrost raises the threat of a re-emergence of microorganisms some of which were shown to remain viable in ancient frozen soils for up to half a million years. In order to evaluate this risk, it is of interest to acquire a better knowledge of the composition of the microbial communities found in this understudied environment. Here we present a metagenomics analysis of 12 soil samples from Russian Arctic and subarctic pristine areas: Chukotka, Yakutia, and Kamchatka, including 9 permafrost samples collected at various depths. These large datasets (9.2 1011 total bp) were assembled (525,313 contigs 〉 5kb), their encoded protein contents predicted, then used to perform taxonomical assignments of bacterial, archaeal, and eukaryotic organisms, as well as DNA viruses. The various samples exhibited variable DNA contents and highly diverse taxonomic profiles showing no obvious relationship with their locations, depths or deposit ages. Bacteria represented the largely dominant DNA fraction (95%) in all samples, followed by archaea (3.2%), surprisingly little eukaryotes (0.5%), and viruses (0.4%). Although no common taxonomic pattern was identified, the samples shared unexpected high frequencies of β-lactamase genes, almost 0.9 copy/bacterial genome. In addition of known environmental threats, the particularly intense warming of the Arctic might thus enhance the spread of bacterial antibiotic resistances, today's major challenge in public health. β-lactamases were also observed at high frequency in other types of soils, suggesting their general role in the regulation of bacterial populations.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 22
    Publication Date: 2023-10-26
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2021. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: Relative location of microearthquakes that occurred at Mt Pollino (Italy) from 2011 to 2013 have been analyzed with the aim of a detailed imaging of the geometry of active faults. We identified 27 clusters composed of a number of earthquakes from 9 to 33, with local magnitude in the range 0.6–2.7. The relative location shows that the distribution of hypocentres in each cluster is characterized by extension from few tens of meters to at most 350 m. For each cluster the hypocentre distribution was fitted by a plane to infer the fault orientation, and results were compared with the fault plane solutions corresponding to the focal mechanism of earthquakes of the same cluster. The comparison shows a good agreement in most of the cases. The relative location analysis, generally applied to earthquakes with similar waveform, has been improved to permit also the relative location of earthquakes characterized by not similar signals. To achieve this purpose a modified procedure that overcome the condition of very similar waveforms has been applied to estimate the time delay between first pulses of the master events. The relative location of master events of all clusters shows a precise imaging of the relative position of all analysed sources and allows also to follow with high accuracy the evolution in time of the seismic swarm within the selected periods. The hypocentre position of master events and the nearly parallel fitting planes of any clusters suggest that most of the analyzed earthquakes were produced by different patches of the same fault. The final results depict a main fault plane characterized by NW–SE strike, dip of about 35–45° and depth between 4.5 and 6.5 km b.s.l. Focal mechanisms, used also to evaluate the local stress field, are mostly of normal type with few strike slip solutions for the shallowest events. This result is in good agreement with the local tectonic stress regime that is characterized by predominant NE–SW transtension, as inferred from structural, seismological and geophysical data.
    Description: Published
    Description: 637–648
    Description: 1T. Struttura della Terra
    Description: JCR Journal
    Keywords: Persistence, memory, correlations, clustering, Spatial analysis, Crustal imaging, Earthquake source observations, Seismicity and tectonics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 23
    Publication Date: 2023-10-31
    Description: Since the Mesozoic, central and eastern European tectonics have been dominated by the closure of the Tethyan Ocean as the African and European plates collided. In the Miocene, the edge of the East European Craton and Moesian Platform were reworked in collision during the Carpathian orogeny and lithospheric extension formed the Pannonian Basin. To investigate the mantle deformation signatures associated with this complex collisional-extensional system, we carry out SKS splitting analysis at 123 broad-band seismic stations in the region. We compare our measurements with estimates of lithospheric thickness and recent seismic tomography models to test for correlation with mantle heterogeneities. Reviewing splitting delay times in light of xenolith measurements of anisotropy yields estimates of anisotropic layer thickness. Fast polarization directions are mostly NW–SE oriented across the seismically slow West Carpathians and Pannonian Basin and are independent of geological boundaries, absolute plate motion direction or an expected palaeo-slab roll-back path. Instead, they are systematically orthogonal to maximum stress directions, implying that the indenting Adria Plate, the leading deformational force in Central Europe, reset the upper-mantle mineral fabric in the past 5 Ma beneath the Pannonian Basin, overprinting the anisotropic signature of earlier tectonic events. Towards the east, fast polarization directions are perpendicular to steep gradients of lithospheric thickness and align along the edges of fast seismic anomalies beneath the Precambrian-aged Moesian Platform in the South Carpathians and the East European Craton, supporting the idea that craton roots exert a strong influence on the surrounding mantle flow. Within the Moesian Platform, SKS measurements become more variable with Fresnel zone arguments indicating a shallow fossil lithospheric source of anisotropy likely caused by older tectonic deformation frozen in the Precambrian. In the Southeast Carpathian corner, in the Vrancea Seismic Zone, a lithospheric fragment that sinks into the mantle is sandwiched between two slow anomalies, but smaller SKS delay times reveal weaker anisotropy occurs mainly to the NW side, consistent with asymmetric upwelling adjacent to a slab, slower mantle velocities and recent volcanism.
    Description: Published
    Description: 2105–2118
    Description: 1T. Struttura della Terra
    Description: JCR Journal
    Keywords: Seismic anisotropy ; geodynamics ; Seismic anisotropy and geodynamics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 24
    Publication Date: 2023-11-21
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2021. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: On 24 August 2016 at 01:36 UTC a ML6.0 earthquake struck several villages in central Italy, among which Accumoli, Amatrice and Arquata del Tronto. The earthquake was recorded by about 350 seismic stations, causing 299 fatalities and damage with macroseismic intensities up to 11. The maximum acceleration was observed at Amatrice station (AMT) reaching 916 cm s–2 on E–W component, with epicentral distance of 15 km and Joyner and Boore distance to the fault surface (RJB) of less than a kilometre. Motivated by the high levels of observed ground motion and damage, we generate broad-band seismograms for engineering purposes by adopting a hybrid method. To infer the low frequency seismograms, we considered the kinematic slip model by Tinti et al . The high frequency seismograms were produced using a stochastic finite-fault model approach based on dynamic corner-frequency. Broadband synthetic time-series were therefore obtained by merging the low and high frequency seismograms. Simulated hybrid ground motions were compared both with the observed ground motions and the ground-motion prediction equations (GMPEs), to explore their performance and to retrieve the region-specific parameters endorsed for the simulations. In the near-fault area we observed that hybrid simulations have a higher capability to detect near source effects and to reproduce the source complexity than the use of GMPEs. Indeed, the general good consistency found between synthetic and observed ground motion (both in the time and frequency domain), suggests that the use of regional-specific source scaling and attenuation parameters together with the source complexity in hybrid simulations improves ground motion estimations. To include the site effect in stochastic simulations at selected stations, we tested the use of amplification curves derived from HVRSs (horizontal-to-vertical response spectra) and from HVSRs (horizontal-to-vertical spectral ratios) rather than the use of generic curves according to NTC18 Italian seismic design code. We generally found a further reduction of residuals between observed and simulated both in terms of time histories and spectra.
    Description: Published
    Description: 1753–1779
    Description: 6T. Studi di pericolosità sismica e da maremoto
    Description: JCR Journal
    Keywords: 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 25
    Publication Date: 2023-11-16
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2020. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved
    Description: This study describes a deep convolutional neural network (CNN) based technique for the prediction of intensity measurements (IMs) of ground shaking. The input data to the CNN model consists of multistation 3C broadband and accelerometric waveforms recorded during the 2016 Central Italy earthquake sequence for M $\ge$ 3.0. We find that the CNN is capable of predicting accurately the IMs at stations far from the epicenter and that have not yet recorded the maximum ground shaking when using a 10 s window starting at the earthquake origin time. The CNN IM predictions do not require previous knowledge of the earthquake source (location and magnitude). Comparison between the CNN model predictions and the predictions obtained with Bindi et al. (2011) GMPE (which require location and magnitude) has shown that the CNN model features similar error variance but smaller bias. Although the technique is not strictly designed for earthquake early warning, we found that it can provide useful estimates of ground motions within 15-20 sec after earthquake origin time depending on various setup elements (e.g., times for data transmission, computation, latencies). The technique has been tested on raw data without any initial data pre-selection in order to closely replicate real-time data streaming. When noise examples were included with the earthquake data, the CNN was found to be stable predicting accurately the ground shaking intensity corresponding to the noise amplitude.
    Description: Published
    Description: 1379–1389
    Description: 8T. Sismologia in tempo reale
    Description: JCR Journal
    Keywords: Physics - Geophysics; Physics - Geophysics ; 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 26
    Publication Date: 2023-11-16
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2020. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: In volcanoes, topography, shallow heterogeneity and even shallow morphology can substan- tially modify seismic coda signals. Coda waves are an essential tool to monitor eruption dynamics and model volcanic structures jointly and independently from velocity anomalies: it is thus fundamental to test their spatial sensitivity to seismic path effects. Here, we apply the Multiple Lapse Time Window Analysis (MLTWA) to measure the relative importance of scattering attenuation vs absorption at Mount St Helens volcano before its 2004 erup- tion. The results show the characteristic dominance of scattering attenuation in volcanoes at lower frequencies (3–6 Hz), while absorption is the primary attenuation mechanism at 12 and 18 Hz. Scattering attenuation is similar but seismic absorption is one order of magnitude lower than at open-conduit volcanoes, like Etna and Kilauea, a typical behaviour of a (rela- tively) cool magmatic plumbing system. Still, the seismic albedo (measuring the ratio between seismic energy emitted and received from the area) is anomalously high (0.95) at 3 Hz. A radiative-transfer forward model of far- and near-field envelopes confirms this is due to strong near-receiver scattering enhancing anomalous phases in the intermediate and late coda across the 1980 debris avalanche and central crater. Only above this frequency and in the far-field diffusion onsets at late lapse times. The scattering and absorption parameters derived from MLTWA are used as inputs to construct 2-D frequency-dependent bulk sensitivity kernels for the S-wave coda in the multiple-scattering (using the Energy Transport Equations—ETE) and diffusive (AD, independent of MLTWA results) regimes. At 12 Hz, high coda-attenuation anomalies characterize the eastern side of the volcano using both kernels, in spatial correla- tion with low-velocity anomalies from literature. At 3 Hz, the anomalous albedo, the forward modelling, and the results of the tomographic imaging confirm that shallow heterogeneity beneath the extended 1980 debris-avalanche and crater enhance anomalous intermediate and late coda phases, mapping shallow geological contrasts. We remark the effect this may have on coda-dependent source inversion and tomography, currently used across the world to image and monitor volcanoes. At Mount St Helens, higher frequencies and deep borehole data are necessary to reconstruct deep volcanic structures with coda waves.
    Description: Scottish Alliance for Geosciences Environment and Society and the Kleinman Grant for Volcano Research
    Description: Published
    Description: 169-188
    Description: 1T. Struttura della Terra
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: 3IT. Calcolo scientifico
    Description: JCR Journal
    Keywords: NorthAmerica ; Wave scattering and diffraction. ; Codawaves ; Seismicattenuation ; Seismic tomography ; Volcano seismology ; 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 27
    Publication Date: 2023-11-14
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2020. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: To evaluate the site response using both empirical approaches (e.g. standard spectral ratio, ground motion models (GMMs), generalized inversion techniques, etc.) and numerical 1-D/2-D analyses, the definition of the reference motion, that is the ground motion recorded at stations unaffected by site-effects due to topographic, stratigraphic or basin effects, is needed. The main objective of this work is to define a robust strategy to identify the seismic stations that can be considered as reference rock sites, using six proxies for the site response: three proxies are related to the analysis of geophysical and seismological data (the repeatable site term from the residual analysis, the resonance frequencies from horizontal-to-vertical spectral ratios on noise or earthquake signals, the average shear wave velocity in the first 30 m); the remaining ones concern geomorphological and installation features (outcropping rocks or stiff soils, flat topography and absence of interaction with structures). We introduce a weighting scheme to take into account the availability and the quality of the site information, as well as the fulfillment of the criterion associated to each proxy. We also introduce a hierarchical index, to take into account the relevance of the proposed proxies in the description of the site effects, and an acceptance threshold for reference rock sites identification. The procedure is applied on a very large data set, composed by accelerometric and velocimetric waveforms, recorded in Central Italy in the period 2008–2018. This data set is composed by more than 30 000 waveforms relative to 450 earthquakes in the magnitude range 3.2–6.5 and recorded by more than 450 stations. A total of 36 out of 133 candidate stations are identified as reference sites: the majority of them are installed on rock with flat topography, but this condition is not sufficient to guarantee the absence of amplifications, especially at high frequencies. Seismological analyses are necessary to exclude stations affected by resonances. We test the impact of using these sites by calibrating a GMMs. The results show that for reference rock sites the median predictions are reduced down to about 45 per cent at short periods in comparison to the generic rock motions.
    Description: Published
    Description: 2053–2067
    Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 28
    Publication Date: 2023-11-14
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2020. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: We compile a data set of Rayleigh-wave phase velocities between pairs of stations, based on teleseismic events located on the same great circle as the two stations. We validate our observations against dispersion estimates based on ambient-noise cross correlations at the same station pairs. Discrepancies between the results of the two methods can in principle be explained by deviations in the wave propagation path between earthquake and receivers, due to lateral heterogeneity in the Earth’s structure, but the latter effect has, so far, not been precisely quantified nor corrected for. We implement an algorithm to measure the arrival angle of earthquake-generated surface waves and correct the dispersion measurements accordingly. Application to a data set from the Central-Western Mediterranean shows that the arrival-angle correction almost entirely accounts for the discrepancy in question, decreasing significantly the velocity bias for a wide range of periods.
    Description: Published
    Description: 1838–1844
    Description: 1T. Struttura della Terra
    Description: JCR Journal
    Keywords: 04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 29
    Publication Date: 2023-11-16
    Description: This article has been accepted for publication in Geophysical Journal International ©: The Authors 2021. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. Uploaded in accordance with the publisher's self-archiving policy.
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2021. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: Three dimensional attenuation images of Mt Etna volcano obtained by the analysis of Q-coda from local volcano-tectonic earthquakes are presented in this work. Seismic sources are confined inside the Etna structure with a maximum focal depth of 35 km below the sea level. The space distribution of the attenuation values was calculated by using 3-D weighting functions derived by the sensitivity kernels of Pacheco & Snieders and approximated by a polynomial interpolation, represented in the maps by using a backprojection method. Data were analyzed in four bands with central frequency placed at 1.5, 3, 6 and 12 Hz, respectively. We observed a frequency dependence of Q-coda with values that range from 55 at 1.5 Hz to 218 at 12 Hz. Q-coda space distribution in the Etna area shows almost uniformity in the average attenuation in the first 35 km below the surface. The images were derived with a resolution of 5 km. We observe as one of our main conclusions that Q-coda attenuation space anomalies are correlated with the areas of highest structural heterogeneities and are distributed along the well-known tectonic structures which characterize the crust in Mt Etna region. Previous and numerous velocity and attenuation images describing the structure of Mt Etna support our main conclusion: high Q-coda volumes almost coincide with the zones marked by high velocity and relative low total attenuation for direct waves.
    Description: Published
    Description: 544–558
    Description: 2V. Struttura e sistema di alimentazione dei vulcani
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 30
    Publication Date: 2023-11-29
    Description: This article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2020. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy. All rights reserved.
    Description: On 24 January 2020 an Mw 6.8 earthquake occurred at 20:55 local time (17:55 UTC) in eastern Turkey, close to the town of Sivrice in the Elazığ province, causing widespread considerable seismic damage in buildings. In this study, we analyse the main features of the rupture process and the seismic ground shaking during the Elazığ earthquake. We first use Interferometric Synthetic Aperture Radar (InSAR) interferograms (Sentinel-1 satellites) to constrain the fault geometry and the coseismic slip distribution of the causative fault segment. Then, we utilize this information to analyse the ground motion characteristics of the main shock in terms of peak ground acceleration (PGA), peak ground velocity (PGV) and spectral accelerations. The absence of seismic registrations in near-field for this earthquake imposes major constraints on the computation of seismic ground motion estimations in the study area. To do this, we have used a stochastic finite-fault simulation method to generate high-frequency ground motions synthetics for the Mw 6.8 Elazığ 2020 earthquake. Finally, we evaluate the potential state of stress of the unruptured portions of the causative fault segment as well as of adjacent segments, using the Coulomb stress failure function variations. Modelling of geodetic data shows that the 2020 Elazığ earthquake ruptured two major slip patches (for a total length of about 40 km) located along the Pütürge segment of the well-known left-lateral strike-slip East Anatolian Fault Zone (EAFZ), with up to 2.3 m of slip and an estimated geodetic moment of 1.70 × 1019 Nm (equivalent to a Mw 6.8). The position of the hypocentre supports the evidence of marked WSW rupture directivity during the main shock. In terms of ground motion characteristics, we observe that the high-frequency stochastic ground motion simulations have a good capability to reproduce the source complexity and capture the ground motion attenuation decay as a function of distance, up to the 200 km. We also demonstrate that the design spectra corresponding to 475 yr return period, provided by the new Turkish building code is not exceeded by the simulated seismograms in the epicentral area where there are no strong motion stations and no recordings available. Finally, based on the Coulomb stress distribution computation, we find that the Elazığ main shock increased the stress level of the westernmost part of the Pütürge fault and of the adjacent Palu segment and as a result of an off-fault lobe.
    Description: Published
    Description: 1054–1068
    Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 31
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    Unknown
    Oxford University Press
    In:  EPIC3Conservation Physiology, Oxford University Press, 9(1), ISSN: 2051-1434
    Publication Date: 2024-01-01
    Description: We studied the ontogeny of osmoregulation of the Asian shore crab Hemigrapsus sanguineus at an invaded area in the North Sea. H. sanguineus is native to Japan and China but has successfully invaded the Atlantic coast of North America and Europe. In the invaded areas, H. sanguineus is becoming a keystone species as driver of community structure and the adults compete with the shore crab Carcinus maenas. Strong osmoregulatory abilities may confer the potential to use and invade coastal areas already earlier in the life cycle. We reared larvae and first juveniles at 24°C in seawater from hatching to intermoult of each developmental stage (zoea I-V, megalopa, crab I). We exposed each stage to a range of salinities (0–39 ppt) for 24 h, and then we quantified haemolymph osmolality, using nano-osmometry. In addition, we quantified osmolality in field-collected adults after acclimation to the test salinities for 6 days. Larvae of H. sanguineus were able to hyper-osmoregulate at low salinities (15 and 20 ppt) over the complete larval development, although the capacity was reduced at the zoeal stage V; at higher salinities (25–39 ppt), all larval stages were osmoconformers. The capacity to slightly hypo-regulate at high salinity appeared in the first juvenile. Adults were able to hyper-osmoregulate at low salinities and hypo-regulate at concentrated seawater (39 ppt). H. sanguineus showed a strong capacity to osmoregulate as compared to its native competitor C. maenas, which only hyper-regulates at the first and last larval stages and does not hypo-regulate at the juvenile-adult stages. The capacity of H. sanguineus to osmoregulate over most of the life cycle should underpin the potential to invade empty niches in the coastal zone (characterized by low salinity and high temperatures). Osmoregulation abilities over the whole life cycle also constitute a strong competitive advantage over C. maenas.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , NonPeerReviewed
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  • 32
    Publication Date: 2021-10-27
    Description: Galactic black hole X-ray binaries (BHXBs) provide excellent laboratories to study accretion, as their relatively quick evolution allows us to monitor large changes in the in-flowing and/or out-flowing material over human timescales. However, the details of how the inflow-outflow coupling evolves during a BHXB outburst remain an area of active debate. In this work we attempt to probe the physical changes underlying the system evolution, by performing a systematic analysis of the multi-wavelength data of three BHXB sources: XTE J1752-223, MAXI J1659-152, and XTE J1650-500, during hard and hard-intermediate states. Using the power spectral hue which characterises the X-ray variability properties, we identify several clusters of BHXB epochs and perform the joint multi-wavelength spectral modelling to test their commonality with a physical jet model. Under the assumption that the corona is related to the base of the jet, we find that the power spectral hue traces the variation of the coronal radius (from ∼10Rg − ∼ 40Rg) in multiple BHXBs at hard and hard-intermediate states, and that the data are consistent with moderately truncated accretion discs (
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  • 33
    Publication Date: 2021-10-27
    Description: We describe the Dark Energy Survey (DES) Deep Fields, a set of images and associated multi-wavelength catalogue (ugrizJHKs) built from Dark Energy Camera (DECam) and Visible and Infrared Survey Telescope for Astronomy (VISTA) data. The DES Deep Fields comprise 11 fields (10 DES supernova fields plus COSMOS), with a total area of ∼30 square degrees in ugriz bands and reaching a maximum i-band depth of 26.75 (AB, 10σ, 2″). We present a catalogue for the DES 3-year cosmology analysis of those four fields with full 8-band coverage, totalling 5.88 sq. deg. after masking. Numbering 2.8million objects (1.6million post masking), our catalogue is drawn from images coadded to consistent depths of r = 25.7, i = 25, z = 24.3 mag. We use a new model-fitting code, built upon established methods, to deblend sources and ensure consistent colours across the u-band to Ks-band wavelength range. We further detail the tight control we maintain over the point-spread function modelling required for the model fitting, astrometry and consistency of photometry between the four fields. The catalogue allows us to perform a careful star-galaxy separation and produces excellent photometric redshift performance (NMAD = 0.023 at i 〈 23). The Deep-Fields catalogue will be made available as part of the cosmology data products release, following the completion of the DES 3-year weak lensing and galaxy clustering cosmology work.
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  • 34
    Publication Date: 2021-10-27
    Description: We present a multi-wavelength investigation of the H ii region G347.600+00.211, located at a distance of 7.9 kpc. We analyse the gas and dust properties aiming to disentangle the origin of the region as well as its role in the formation of new stars. G347.600+00.211 is very conspicuous at 1420 MHz and infrared wavelengths, showing an incomplete shell-like structure with two distinct zones of very intense emission. The infrared bubble S8 is part of the shell structure. The spatial distribution of the molecular gas shows the presence of six clouds located around the ionized region and showing a good morphological correlation with the 8 μm emission. Cold dust is coincident with the dense gas shown in the CO measurements. As for the origin of the region, we found that the massive cluster [DBS2003]179 and two Wolf–Rayet (WR) stars are located at the same distance than the ionized gas. Based on a stellar density analysis, we inferred that one of the WR stars, 1181-81L, is also a probable member of the cluster. Both the cluster and the WR stars are not only within the ring–like structure, but are also located near the two spots of very heightened emission, suggesting they may be responsible for this bright emission. Finally, as expanding H ii regions are hypothesised to trigger star formation, we used different infrared point source catalogues to search for young stellar object candidates (cYSOs). A total of 33 cYSOs and 4 CH ii regions were identified projected on to the photo–dissociation regions and molecular clouds.
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  • 35
    Publication Date: 2021-10-27
    Description: We develop a sophisticated model of FRB observations, accounting for the intrinsic cosmological gas distribution and host galaxy contributions, and give the most detailed account yet of observational biases due to burst width, dispersion measure, and the exact telescope beamshape. Our results offer a significant increase in both accuracy and precision beyond those previously obtained. Using results from ASKAP and Parkes, we present our best-fit FRB population parameters in a companion paper. Here, we consider in detail the expected and fitted distributions in redshift, dispersion measure, and signal-to-noise. We estimate that the unlocalised ASKAP FRBs arise from z 〈 0.5, with between a third and a half within z 〈 0.1. Our predicted source-counts (‘logN–logS’) distribution confirms previous indications of a steepening index near the Parkes detection threshold of 1 Jy ms. We find no evidence for a minimum FRB energy, and rule out Emin 〉 1039.0 erg at 90 per cent C.L. Importantly, we find that above a certain DM, observational biases cause the Macquart (DM–z) relation to become inverted, implying that the highest-DM events detected in the unlocalised Parkes and ASKAP samples are unlikely to be the most distant. More localized FRBs will be required to quantitatively estimate this effect, though its cause is a well-understood observational bias. Works assuming a 1–1 DM–z relation may therefore derive erroneous results. Our analysis of errors suggests that limiting factors in our analysis are understanding of FRB spectral behaviour, sensitivity response of search experiments, and the treatment of the repeating population and luminosity function.
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  • 36
    Publication Date: 2021-10-27
    Description: Neutron stars in low mass X-ray binaries are hypothesised to emit continuous gravitational waves that may be detectable by ground-based observatories. The torque balance model predicts that a higher accretion rate produces larger-amplitude gravitational waves, hence low mass X-ray binaries with high X-ray flux are promising targets for gravitational wave searches. The detection of X-ray pulsations would identify the spin frequency of these neutron stars, and thereby improve the sensitivity of continuous gravitational-wave searches by reducing the volume of the search parameter space. We perform a semi-coherent search for pulsations in the two low mass X-ray binaries Scorpius X-1 and Cygnus X-2 using X-ray data from the Rossi X-ray Timing Explorer Proportional Counter Array. We find no clear evidence for pulsations, and obtain upper limits (at 90 per cent confidence) on the fractional pulse amplitude, with the most stringent being 0.034 per cent for Scorpius X-1 and 0.23 per cent for Cygnus X-2. These upper limits improve upon those in previous work by factors of ∼8.2 and ∼1.6 respectively.
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  • 37
    Publication Date: 2021-10-28
    Description: Here, we report the new detection of three shock fronts using archival Chandra X-ray observations in Abell 1914, which also hosts a radio halo, a radio phoenix, and a head-tail galaxy. In this study, we report the X-ray shock front at the position of the radio phoenix, which further strengthens the scenario that radio phoenix traces old plasma that gets lit up when compressed by shock passage. We further analyse the thermodynamic structure of the cluster in detail. We create temperature maps of A1914 using three different techniques, Adaptive Circular Binning (ACB), Weighted Voronoi Tessellations (WVT), and Contour binning (Contbin) method. These thermodynamic maps, along with the pseudo pressure and the pseudo entropy maps for the cluster, are evidence of disturbed morphology produced by multiple merger events. These merger events create cluster-wide turbulence, which may re-accelerate the relativistic particles and result in a radio halo within the cluster. Further, comparing X-ray and radio images reveals that the radio halo is contained within two X-ray shock fronts. Our analysis suggests that A1914 has both equatorial shock and axial shock within the cluster’s ICM. We proposed a dual merging scenario based on the shock position and analysis of the thermodynamic maps obtained from the deeper Chandra X-ray observations.
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  • 38
    Publication Date: 2021-10-28
    Description: The long-term evolutionary impacts of whole genome duplication (WGD) are strongly influenced by the ensuing rediploidization process. Following autopolyploidization, rediploidization involves a transition from tetraploid to diploid meiotic pairing, allowing duplicated genes (ohnologues) to diverge genetically and functionally. Our understanding of autopolyploid rediploidization has been informed by a WGD event ancestral to salmonid fishes, where large genomic regions are characterized by temporally delayed rediploidization, allowing lineage-specific ohnologue sequence divergence in the major salmonid clades. Here, we investigate the long-term outcomes of autopolyploid rediploidization at genome-wide resolution, exploiting a recent ‘explosion’ of salmonid genome assemblies, including a new genome sequence for the huchen (Hucho hucho). We developed a genome alignment approach to capture duplicated regions across multiple species, allowing us to create 121,864 phylogenetic trees describing genome-wide ohnologue divergence across salmonid evolution. Using molecular clock analysis, we show that 61% of the ancestral salmonid genome experienced an initial ‘wave’ of rediploidization in the late Cretaceous (85-106 Mya). This was followed by a period of relative genomic stasis lasting 17-39 My, where much of the genome remained tetraploid. A second rediploidization wave began in the early Eocene and proceeded alongside species diversification, generating predictable patterns of lineage-specific ohnologue divergence, scaling in complexity with the number of speciation events. Using gene set enrichment, gene expression, and codon-based selection analyses, we provide insights into potential functional outcomes of delayed rediploidization. This study enhances our understanding of delayed autopolyploid rediploidization and has broad implications for future studies of WGD events.
    Print ISSN: 0737-4038
    Electronic ISSN: 1537-1719
    Topics: Biology
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  • 39
    Publication Date: 2021-10-29
    Description: SIRT3 is an NAD+-dependent protein deacetylase localized in mitochondria. Several studies reported localization of SIRT3 in the cytoplasm or nucleus, but data of these studies were not consistent. We detected expression of mitochondrial (SIRT3mt) and cytoplasmic (SIRT3ct) Sirt3 mRNAs in the mouse brain, and we also found SIRT3 immunostaining of mitochondria and cytoplasm in the brain and cultured neural cells. However, expression levels of SIRT3ct in COS cells transfected with SIRT3ct cDNA were much lower than those of SIRT3mt. We found that SIRT3ct but not SIRT3mt was promptly degraded by ubiquitin-dependent degradation, in which SIRT3ct degradation was mediated mainly by ubiquitination of NH2-terminal methionine and partly by that of lysine residues of SIRT3ct. SIRT3ct expression level was significantly enhanced by treatment of cells with staurosporine or H2O2. H2O2 treatment promoted nuclear translocation of SIRT3ct and induced histone H3 deacetylation and superoxide dismutase 2 expression. Overexpression of SIRT3ct decreased cell death caused by H2O2 at levels similar to those achieved by overexpression of SIRT3mt. Knockdown of Sirt3 mRNA increased cell death caused by amyloid-β (Aβ), and overexpression of SIRT3ct suppressed the toxic function of Aβ in PC12 cells. These results indicate that SIRT3ct promotes cell survival under physiological and pathological conditions.
    Print ISSN: 0021-924X
    Electronic ISSN: 1756-2651
    Topics: Biology , Chemistry and Pharmacology
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  • 40
    Publication Date: 2021-10-28
    Description: To assess the number of life-bearing worlds in astrophysical environments, it is necessary to take the intertwined processes of abiogenesis (birth), extinction (death), and transfer of life (migration) into account. We construct a mathematical model that incorporates this trio of mechanisms and accordingly derive the probability distribution function and other statistical properties (e.g. mean) for the number of worlds with biospheres. We show that a given astrophysical setting may become eventually saturated with life if the rate of successful transfers of organisms is higher than the extinction rate of biospheres. Based on the available data, we suggest that this criterion might be fulfilled for star-forming clusters (and perhaps the Galactic bulge under optimal circumstances), thereby indicating that such regions could constitute promising abodes for hosting and detecting life.
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  • 41
    Publication Date: 2021-10-28
    Description: Pathogenic variants that disrupt human mitochondrial protein synthesis are associated with a clinically heterogenous group of diseases. Despite an impairment in oxidative phosphorylation being a common phenotype, the underlying molecular pathogenesis is more complex than simply a bioenergetic deficiency. Currently, we have limited mechanistic understanding on the scope by which a primary defect in mitochondrial protein synthesis contributes to organelle dysfunction. Since the proteins encoded in the mitochondrial genome are hydrophobic and need co-translational insertion into a lipid bilayer, responsive quality control mechanisms are required to resolve aberrations that arise with the synthesis of truncated and misfolded proteins. Here, we show that defects in the OXA1L-mediated insertion of MT-ATP6 nascent chains into the mitochondrial inner membrane are rapidly resolved by the AFG3L2 protease complex. Using pathogenic MT-ATP6 variants, we then reveal discrete steps in this quality control mechanism and the differential functional consequences to mitochondrial gene expression. The inherent ability of a given cell type to recognize and resolve impairments in mitochondrial protein synthesis may in part contribute at the molecular level to the wide clinical spectrum of these disorders.
    Print ISSN: 0964-6906
    Electronic ISSN: 1460-2083
    Topics: Biology , Medicine
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  • 42
    Publication Date: 2021-10-30
    Description: Motivation Coiled-coil is composed of two or more helices that are wound around each other. It widely exists in proteins and has been discovered to play a variety of critical roles in biology processes. Generally, there are three types of structural features in coiled-coil: coiled-coil domain (CCD), oligomeric state, and register. However, most of the existing computational tools only focus on one of them. Results Here, we describe a new deep learning model, CoCoPRED, which is based on convolutional layers, bidirectional long short-term memory, and attention mechanism. It has three networks, i.e., CCD network, oligomeric state network, and register network, corresponding to the three types of structural features in coiled-coil. This means CoCoPRED has the ability of fulfilling comprehensive prediction for coiled-coil proteins. Through the 5-fold cross-validation experiment, we demonstrate that CoCoPRED can achieve better performance than the state-of-the-art models on both CCD prediction and oligomeric state prediction. Further analysis suggests the CCD prediction may be a performance indicator of the oligomeric state prediction in CoCoPRED. The attention heads in CoCoPRED indicate that registers a, b, and e are more crucial for the oligomeric state prediction. Availability CoCoPRED is available at http://www.csbio.sjtu.edu.cn/bioinf/CoCoPRED. Supplementary information Supplementary data are available at Bioinformatics online.
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  • 43
    Publication Date: 2021-10-28
    Description: Studies of planetary systems of stars in star-forming regions and young clusters open a window on the formative stages of planetary evolution. We obtained high-cadence high-resolution infrared spectroscopy of the solar-mass Taurus association-member V1298 Tau during a transit of its 10R⊕-size ‘b’ planet. We measured the systemic radial velocity and find that the kinematics of V1298 Tau suggest an affiliation with a ≳6 Myr-old subgroup. A comparison of V1298 Tau and the nearby, co-moving star 2M0405 with stellar evolution models suggests an age of ∼10-25 Myr. We measured the projected spin-orbit angle of ‘b’ as $lambda =15_{-16}^{+15}$ and $lambda = 2_{-4}^{+12}$ degrees using the apparent RV shift and change in line profile, respectively, induced by the transient occultation of the rotating star by the planet. These values indicate a prograde orbit like that of the interior ‘c’ planet of V1298 Tau and point to a co-planar multi-planet system that formed within a disk. We also measured variation in the strength of the 1083 nm triplet of neutral orthohelium as a probe of any extended/escaping atmosphere around ‘b’. We detect a steady decrease in absorption over the transit which appears to arise from the star or its planetary system. While this variation could be ascribed to ‘b’ or possibly to the immediately preceding transit of ‘d’, we cannot rule out that this is due to rapid variation in the stellar disk-integrated flux in the triplet. The amplitude of variation (∼0.04 nm) is consistent with moderate estimates of atmospheric escape driven by XUV radiation from the central star.
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  • 44
    Publication Date: 2021-10-28
    Description: We present light curve analyses of two newly identified detached eclipsing binaries, HD 96609 and HD 303734, in the region of the richly populated open cluster NGC 3532. HD 96609 is composed of two main sequence stars (B9-A0V + A2V) with masses and radii of M1 = 2.66 ± 0.02M⊙, M2 = 1.84 ± 0.01M⊙, R1 = 2.740 ± 0.006R⊙, R2 = 1.697 ± 0.005R⊙. The positions of the components on log M − log R plane suggests log(age/yr) 8.55, corresponding 350 ± 40 Myr of age, which agrees with the 300 ± 100 Myr age of NGC 3532 estimated in previous studies. We find the distance of HD 96609 as 460 ± 17 pc, which is consistent with the $484^{+35}_{-30}$ pc distance of NGC 3532, estimated from GAIA parallaxes. HD 303734 is an interesting totally eclipsing binary with a quite shallow secondary eclipse. Using photometric properties of the system in conjunction with theoretical calibrations, we estimate that HD 303734 consists of A6V + K3V components. HD 96609 and HD 303734 are the second and third eclipsing binaries discovered in the region of NGC 3532, after the first one, GV Car.
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  • 45
    Publication Date: 2021-10-28
    Description: We propose a novel approach to obtain the growth rate of cosmic structures, f(z), from the evolution of the cosmic homogeneity scale, RH(z). Our methodology needs two ingredients in a specific functional form: RH(z) data and the matter two-point correlation function today, i.e., ξ(r, z = 0). We use a Gaussian Process approach to reconstruct the function RH. In the absence of suitable observational information of the matter correlation function in the local Universe, z ≃ 0, we assume a fiducial cosmology to obtain ξ(r, z = 0). For this reason, our final result turns out to be a consistency test of the cosmological model assumed. Our results show a good agreement between: (i) the growth rate $f^{R_{ext{H}}}(z)$ obtained through our approach, (ii) the fΛCDM(z) expected in the fiducial model, and (iii) the best-fit f(z) from data compiled in the literature. Moreover, using this data compilation, we perform a Gaussian Process to reconstruct the growth rate function fdata(z) and compare it with the function $f^{R_{ext{H}}}(z)$ finding a concordance of
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  • 46
    Publication Date: 2021-10-30
    Description: Motivation Adverse Outcome Pathways (AOPs) are a conceptual framework developed to support the use of alternative toxicology approaches in the risk assessment. AOPs are structured linear organizations of existing knowledge illustrating causal pathways from the initial molecular perturbation triggered by various stressors, through key events (KEs) at different levels of biology, to the ultimate health or ecotoxicological adverse outcome. Results Artificial intelligence can be used to systematically explore available toxicological data that can be parsed in the scientific literature. Recently a tool called AOP-helpFinder was developed to identify associations between stressors and KEs supporting thus documentation of AOPs. To facilitate the utilization of this advanced bioinformatics tool by the scientific and the regulatory community, a webserver was created. The proposed AOP-helpFinder webserver uses better performing version of the tool which reduces the need for manual curation of the obtained results. As an example, the server was successfully applied to explore relationships of a set of endocrine disruptors with metabolic-related events. The AOP-helpFinder webserver assists in a rapid evaluation of existing knowledge stored in the PubMed database, a global resource of scientific information, to build AOPs and Adverse Outcome Networks (AONs) supporting the chemical risk assessment. Availability and implementation AOP-helpFinder is available at http://aop-helpfinder.u-paris-sciences.fr/index.php
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  • 47
    Publication Date: 2021-10-30
    Description: Motivation Differential network inference is a fundamental and challenging problem to reveal gene interactions and regulation relationships under different conditions. Many algorithms have been developed for this problem; however, they do not consider the differences between the importance of genes, which may not fit the real-world situation. Different genes have different mutation probabilities, and the vital genes associated with basic life activities have less fault tolerance to mutation. Equally treating all genes may bias the results of differential network inference. Thus, it is necessary to consider the importance of genes in the models of differential network inference. Results Based on the Gaussian graphical model with adaptive gene importance regularization, we develop a novel importance-penalized joint graphical Lasso method, IPJGL, for differential network inference. The presented method is validated by the simulation experiments as well as the real datasets. Furthermore, to precisely evaluate the results of differential network inference, we propose a new metric named APC2 for the differential levels of gene pairs. We apply IPJGL to analyze the TCGA colorectal and breast cancer datasets and find some candidate cancer genes with significant survival analysis results, including SOST for colorectal cancer and RBBP8 for breast cancer. We also conduct further analysis based on the interactions in the Reactome database and confirm the utility of our method. Availability R source code of importance-penalized joint graphical lasso is freely available at https://github.com/Wu-Lab/IPJGL. Supplementary information Supplementary materials are available at Bioinformatics online.
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  • 48
    Publication Date: 2021-10-28
    Description: Evolutionary radiation is a widely recognized mode of species diversification, but its underlying mechanisms have not been unambiguously resolved for species-rich cosmopolitan plant genera. In particular, it remains largely unknown how biological and environmental factors have jointly driven its occurrence in specific regions. Here we use Rhododendron, the largest genus of woody plants in the Northern Hemisphere, to investigate how geographic and climatic factors, as well as functional traits, worked together to trigger plant evolutionary radiations and shape the global patterns of species richness based on a solid species phylogeny. Using 3437 orthologous nuclear genes, we reconstructed the first highly supported and dated backbone phylogeny of Rhododendron comprising 200 species that represent all subgenera, sections, and nearly all multi-species subsections, and found that most extant species originated by evolutionary radiations when the genus migrated southwards from circumboreal areas to tropical/subtropical mountains, showing rapid increases of both net diversification rate and evolutionary rate of environmental factors in the Miocene. We also found that the geographically uneven diversification of Rhododendron led to a much higher diversity in Asia than in other continents, which was mainly driven by two environmental variables, i.e., elevation range and annual precipitation, and were further strengthened by the adaptation of leaf functional traits. Our study provides a good example of integrating phylogenomic and ecological analyses in deciphering the mechanisms of plant evolutionary radiations, and sheds new light on how the intensification of the Asian monsoon has driven evolutionary radiations in large plant genera of the Himalaya-Hengduan Mountains.
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  • 49
    Publication Date: 2021-10-30
    Description: Background Almost half of aromatase inhibitor (AI)-treated breast cancer patients experience AI-associated musculoskeletal symptoms (AIMSS); 20-30% discontinue treatment because of severe symptoms. We hypothesized that we could identify predictors of pain reduction in AIMSS intervention trials by combining data from previously conducted trials. Methods We pooled patient-level data from 3 randomized trials testing interventions (omega-3 fatty acids, acupuncture, and duloxetine) for AIMSS that had similar eligibility criteria and the same patient-reported outcome measures. Only patients with baseline Brief Pain Inventory (BPI) average pain score of ≥ 4 of 10 were included. The primary outcome examined was 2-point reduction in average pain from baseline to week 12. Variable cut-point selection and logistic regression were used. Risk models were built by summing the number of factors statistically significantly associated with pain reduction. Analyses were stratified by study and adjusted for treatment arm. Results For the 583 analyzed patients, the four factors statistically significantly associated with pain reduction were FACT Functional Well-Being 〉24 and Physical Well-Being 〉14 (higher scores reflect better function), and WOMAC
    Electronic ISSN: 2515-5091
    Topics: Chemistry and Pharmacology , Medicine
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  • 50
    Publication Date: 2021-10-28
    Description: Motivation DNA Methylation plays a key role in a variety of biological processes. Recently, Nanopore long-read sequencing has enabled direct detection of these modifications. As a consequence, a range of computational methods have been developed to exploit Nanopore data for methylation detection. However, current approaches rely on a human-defined threshold to detect the methylation status of a genomic position and are not optimized to detect sites methylated at low frequency. Furthermore, most methods employ either the Nanopore signals or the basecalling errors as the model input and do not take advantage of their combination. Results Here we present DeepMP, a convolutional neural network (CNN)-based model that takes information from Nanopore signals and basecalling errors to detect whether a given motif in a read is methylated or not. Besides, DeepMP introduces a threshold-free position modification calling model sensitive to sites methylated at low frequency across cells. We comprehensively benchmarked DeepMP against state-of-the-art methods on E. coli, human and pUC19 datasets. DeepMP outperforms current approaches at read-based and position-based methylation detection across sites methylated at different frequencies in the three datasets. Availability DeepMP is implemented and freely available under MIT license at https://github.com/pepebonet/DeepMP Supplementary information Supplementary data are available at Bioinformatics online.
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    Publication Date: 2021-10-29
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  • 52
    Publication Date: 2021-10-28
    Description: Motivation With the advancement of sequencing technologies, genomic data sets are constantly being expanded by high volumes of different data types. One recently introduced data type in genomic science is genomic signals, which are usually short-read coverage measurements over the genome. To understand and evaluate the results of such studies, one needs to understand and analyze the characteristics of the input data. Results SigTools is an R-based genomic signals visualization package developed with two objectives: 1) to facilitate genomic signals exploration in order to uncover insights for later model training, refinement, and development by including distribution and autocorrelation plots. 2) to enable genomic signals interpretation by including correlation, and aggregation plots. In addition, our corresponding web application, SigTools-Shiny, extends the accessibility scope of these modules to people who are more comfortable working with graphical user interfaces instead of command-line tools. Availability SigTools source code, installation guide, and manual is freely available on http://github.com/shohre73.
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  • 53
    Publication Date: 2021-10-29
    Description: Quantifying the flux of cosmic rays reaching exoplanets around M dwarfs is essential to understand their possible effects on exoplanet habitability. Here, we investigate the propagation of Galactic cosmic rays as they travel through the stellar winds (astrospheres) of five nearby M dwarfs, namely: GJ 15A, GJ 273, GJ 338B, GJ 411 and GJ 887. Our selected stars each have 1 or 2 detected exoplanets and they all have wind mass-loss rates constrained by Lyman-α observations. Our simulations use a combined 1D magnetohydrodynamic (MHD) Alfvén-wave-driven stellar wind model and 1D cosmic ray transport model. We find that GJ 411 and GJ 887 have Galactic cosmic rays fluxes comparable with Earth’s at their habitable zones. On the other hand, GJ 15A, GJ 273 and GJ 338B receive a lower Galactic cosmic ray flux in their habitable zones. All exoplanets in our sample, with exception of GJ 15A c and GJ 411 c, have a significantly lower flux of Galactic cosmic rays than values observed at the Earth because they orbit closer-in. The fluxes found here can be further used for chemical modelling of planetary atmospheres. Finally, we calculate the radiation dose at the surface of the habitable-zone planet GJ 273 b, assuming it has an Earth-like atmosphere. This planet receives up to 209 times less 15 MeV energy cosmic ray fluxes than values observed at Earth. However, for high-energy cosmic rays (∼ GeV), the difference in flux is only 2.3 times smaller, which contributes to GJ 273 b receiving a significant surface radiation dose of 0.13 mSv/yr (40 per cent of the annual dose on Earth’s surface).
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  • 54
    Publication Date: 2021-10-29
    Description: Polycyclic Aromatic Hydrocarbons (PAHs) are carbon-based molecules resulting from the union of aromatic rings and related species, which are likely responsible for strong infrared emission features. In this work, using a sample of 50 Seyfert galaxies (DL 〈 100 Mpc) we compare the circumnuclear (inner kpc) PAH emission of AGN to that of a control sample of star-forming galaxies (22 luminous infrared galaxies and 30 H ii galaxies), and investigate the differences between central and extended PAH emission. Using Spitzer/InfraRed Spectrograph spectral data of Seyfert and star-forming galaxies and newly developed PAH diagnostic model grids, derived from theoretical spectra, we compare the predicted and observed PAH ratios. We find that star-forming galaxies and AGN-dominated systems are located in different regions of the PAH diagnostic diagrams. This suggests that not only are the size and charge of the PAH molecules different, but also the nature and hardness of the radiation field that excite them. We find tentative evidence that PAH ratios in AGN-dominated systems are consistent with emission from larger PAH molecules (Nc 〉 300–400) as well as neutral species. By subtracting the spectrum of the central source from the total, we compare the PAH emission in the central versus extended region of a small sample of AGN. In contrast to the findings for the central regions of AGN-dominated systems, the PAH ratios measured in the extended regions of both type 1 and type 2 Seyfert galaxies can be explained assuming similar PAH molecular size distribution and ionized fractions of molecules to those seen in central regions of star-forming galaxies (100 〈 Nc 〈 300).
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-25
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    Publication Date: 2021-10-29
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  • 60
    Publication Date: 2021-10-30
    Description: Spectroscopy from the final internal data release of the Gaia-ESO Survey (GES) has been combined with Gaia EDR3 to assign membership probabilities to targets observed towards 63 Galactic open clusters and 7 globular clusters. The membership probabilities are based chiefly on maximum likelihood modelling of the 3D kinematics of the targets, separating them into cluster and field populations. From 43211 observed targets, 13985 are identified as highly probable cluster members (P 〉 0.9), with an average membership probability of 0.993. The addition of GES radial velocities successfully drives down the fraction of false positives and we achieve better levels of discrimination in most clusters over the use of astrometric data alone, especially those at larger distances. Since the membership selection is almost purely kinematic, the union of this catalogue with GES and Gaia is ideal for investigating the photometric and chemical properties of clusters as a function of stellar mass, age and Galactic position.
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    Publication Date: 2021-10-29
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  • 62
    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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  • 77
    Publication Date: 2021-10-30
    Description: Over the past decade, studies of dust in the Andromeda galaxy (M31) have shown radial variations in the dust emissivity index (β). Understanding the astrophysical reasons behind these radial variations may give clues about the chemical composition of dust grains, their physical structure, and the evolution of dust. We use 12CO(J=1-0) observations taken by the Combined Array for Research in Millimeter Astronomy (CARMA) and dust maps derived from Herschel images, both with an angular resolution of 8″ and spatial resolution of 30 pc, to study variations in β across an area of ≈ 18.6 kpc2 in M31. We extract sources, which we identify as molecular clouds, by applying the astrodendro algorithm to the 12CO and dust maps, which as a byproduct allows us to compare continuum emission from dust and CO emission as alternative ways of finding molecular clouds. We then use these catalogues to investigate whether there is evidence that β is different inside and outside molecular clouds. Our results confirm the radial variations of β seen in previous studies. However, we find little difference between the average β inside molecular clouds compared to outside molecular clouds, in disagreement with models which predict an increase of β in dense environments. Finally, we find some clouds traced by dust with very little CO which may be either clouds dominated by atomic gas or clouds of molecular gas that contain little CO.
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  • 78
    Publication Date: 2021-10-30
    Description: The continuum emission from radio galaxies can be generally classified into different morphological classes such as FRI, FRII, Bent, or Compact. In this paper, we explore the task of radio galaxy classification based on morphology using deep learning methods with a focus on using a small scale dataset (∼2000 samples). We apply few-shot learning techniques based on Twin Networks and transfer learning techniques using a pre-trained DenseNet model with advanced techniques like cyclical learning rate and discriminative learning to train the model rapidly. We achieve a classification accuracy of over 92% using our best performing model with the biggest source of confusion being between Bent and FRII type galaxies. Our results show that focusing on a small but curated dataset along with the use of best practices to train the neural network can lead to good results. Automated classification techniques will be crucial for upcoming surveys with next generation radio telescopes which are expected to detect hundreds of thousands of new radio galaxies in the near future.
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  • 79
    Publication Date: 2021-10-29
    Description: Summary We deployed a seismic network near the source region of the 2017 Mw 6.5 Jiuzhaigou earthquake to monitor aftershock activity and to investigate the local fault structure. An aftershock deployment of Array of small Arrays (AsA) and a Geometric Mean Envelop (GME) algorithm are adopted to enhance detection performance. We also adopt a set of association, relocation, and matched-filter techniques to obtain a detailed regional catalog. 16,742 events are detected and relocated, including 1,279 aftershocks following the Mw 4.8 aftershock. We develop a joint inversion algorithm utilizing locations of event clusters and focal mechanisms to determine the geometry of planar faults. Six segments were finally determined, in which three segments are related to the Huya fault reflecting a change in fault dip direction near the mainshock hypocenter, while the other segments reflect branches showing orthogonal and conjugate geometries with the Huya fault. Aftershocks were active on branching faults between the Huya and Minjiang faults indicating that the mainshock may have ruptured both major faults. We also resolve a fault portion with ‘weak strength’ near the mainshock hypocenter, which is characterized by limited co-seismic slips, concentrated afterslip, low aftershock activities, high b-value, and high sensitivity to stress changes. These phenomena can be explained by fault frictional properties at conditional stable sliding status, which may be related to the localized high pore-fluid pressure produced by the fluid intrusion.
    Print ISSN: 0956-540X
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  • 80
    Publication Date: 2021-10-29
    Description: We study gravitational lensing of gravitational waves from compact object binaries as a probe of compact dark matter (DM) objects such as primordial black holes. Assuming a point mass lens, we perform parameter estimation of lensed gravitational wave signals from compact object binaries to determine the detectability of the lens with ground based laser interferometers. Then, considering binary populations that LIGO-Virgo has been probing, we derive a constraint on the abundance of compact DM from non-observation of lensed events. We find that the LIGO-Virgo observations imply that compact objects heavier than Ml = 200 M⊙ can not constitute all DM and less than $40{{ m per cent}}$ of DM can be in compact objects heavier than Ml = 400 M⊙. We also show that the DM fraction in compact objects can be probed by LIGO in its final sensitivity for Ml 〉 40 M⊙ reaching $2{{ m per cent}}$ of the DM abundance at Ml 〉 200 M⊙, and by ET for Ml 〉 1 M⊙ reaching DM fraction as low as 7 × 10−5 at Ml 〉 40 M⊙.
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  • 81
    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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  • 88
    Publication Date: 2021-10-29
    Description: Summary The Bayesian slip inversion offers a powerful tool for modeling the earthquake source mechanism. It can provide a fully probabilistic result and thus permits us to quantitively assess the inversion uncertainty. The Bayesian problem is usually solved with Monte Carlo methods, but they are computationally expensive and are inapplicable for high-dimensional and large-scale problems. Variational inference is an alternative solver to the Bayesian problem. It turns Bayesian inference into an optimization task and thus enjoys better computational performances. In this study, we introduce a general variational inference algorithm, automatic differentiation variational inference (ADVI), to the Bayesian slip inversion and compare it with the classic Metropolis-Hastings (MH) sampling method. The synthetic test shows that the two methods generate nearly identical mean slip distributions and standard deviation maps. In the real case study, the two methods produce highly consistent mean slip distributions, but the ADVI-derived standard deviation map differs from that produced by the MH method, possibly because of the limitation of the Gaussian approximation in the ADVI method. In both cases, ADVI can give comparable results to the MH method but with a significantly lower computational cost. Our results show that ADVI is a promising and competitive method for the Bayesian slip inversion.
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    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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  • 91
    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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  • 93
    Publication Date: 2021-10-29
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    Publication Date: 2021-10-29
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  • 96
    Publication Date: 2021-05-31
    Description: Two end-to-end ecosystem models, NORWECOM.E2E and NoBa Atlantis, have been used to explore a selection of indicators from the Barents Sea Management plans (BSMP). The indicators included in the BSMP are a combination of simple (e.g. temperature, biomass, and abundance) and complex (e.g. trophic level and biomass of functional groups). The abiotic indicators are found to serve more as a tool to report on climate trends rather than being ecological indicators. It is shown that the selected indicators give a good overview of the ecosystem state, but that overarching management targets and lack of connection between indicators and management actions makes it questionable if the indicator system is suitable for direct use in management as such. The lack of socio-economic and economic indicators prevents a holistic view of the system, and an inclusion of these in future management plans is recommended. The evaluated indicators perform well as an assessment of the ecosystem, but consistency and representativeness are extremely dependent on the time and in what area they are sampled. This conclusion strongly supports the inclusion of an observing system simulation experiment in management plans, to make sure that the observations represent the properties that the indicators need.
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  • 97
    Publication Date: 2021-03-11
    Description: Motivation Genomic DNA replicates according to a reproducible spatiotemporal program, with some loci replicating early in S phase while others replicate late. Despite being a central cellular process, DNA replication timing studies have been limited in scale due to technical challenges. Results We present TIGER (Timing Inferred from Genome Replication), a computational approach for extracting DNA replication timing information from whole genome sequence data obtained from proliferating cell samples. The presence of replicating cells in a biological specimen leads to non-uniform representation of genomic DNA that depends on the timing of replication of different genomic loci. Replication dynamics can hence be observed in genome sequence data by analyzing DNA copy number along chromosomes while accounting for other sources of sequence coverage variation. TIGER is applicable to any species with a contiguous genome assembly and rivals the quality of experimental measurements of DNA replication timing. It provides a straightforward approach for measuring replication timing and can readily be applied at scale. Availability and implementation TIGER is available at https://github.com/TheKorenLab/TIGER. Supplementary information Supplementary data are available at Bioinformatics online.
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  • 98
    Publication Date: 2021-10-28
    Description: Since the first report of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in December 2019, over 100 million people have been infected by COVID-19, millions of whom have died. In the latest year, a large number of omics data have sprung up and helped researchers broadly study the sequence, chemical structure and function of SARS-CoV-2, as well as molecular abnormal mechanisms of COVID-19 patients. Though some successes have been achieved in these areas, it is necessary to analyze and mine omics data for comprehensively understanding SARS-CoV-2 and COVID-19. Hence, we reviewed the current advantages and limitations of the integration of omics data herein. Firstly, we sorted out the sequence resources and database resources of SARS-CoV-2, including protein chemical structure, potential drug information and research literature resources. Next, we collected omics data of the COVID-19 hosts, including genomics, transcriptomics, microbiology and potential drug information data. And subsequently, based on the integration of omics data, we summarized the existing data analysis methods and the related research results of COVID-19 multi-omics data in recent years. Finally, we put forward SARS-CoV-2 (COVID-19) multi-omics data integration research direction and gave a case study to mine deeper for the disease mechanisms of COVID-19.
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    Publication Date: 2021-10-29
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