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The purpose of the research was to assess the genetic and environmental influences on bone properties. One hundred thirty-two pairs of twins (99/33 monozygotic/dizygotic) underwent anthropometric measurements and phalangeal quantitative ultrasound (DBM Sonic 1200, Igea, Italy) measuring the amplitude speed of sound (AD-SoS, m/s). The mean age was 16.78 ± 12.35 years for monozygotic twins and 14.30 ± 8 years for dizygotic. Interpair and intrapair correlations between twins were calculated. In the groups of monozygotic and dizygotic twins, Ad-SoS correlated significantly with age (r = 0.56–0.73, p < 0.05), weight (r = 0.73–0.78, p < 0.05), and height (r = 0.80–0.81, p < 0.05). The strongest intrapair correlation (r = 0.99–0.998) was noted in monozygotic females for Ad-SoS, weight, and height. There was a statistically significant correlation between the intrapair difference of Ad-SoS and age but only in the groups of monozygotic and dizygotic females (r = 0.281, r2 = 0.079, and p = 0.028; r = 0.544, r2 = 0.296, and p = 0.01, respectively). After age adjustment, it was estimated that 28.62% of Ad-SoS in women and 13.2% of Ad-SoS in men was explained by genetic influence, leading to the conclusion that Ad-SoS changed with age, weight, and height. The strongest correlation between pairs of twins was observed in monozygotic twins. The differences in bone values between female twins arose with age, which indicated the role of environmental factors. [ABSTRACT FROM AUTHOR]

By injecting a mixture of gas and pyroclasts into the atmosphere, explosive volcanic eruptions frequently generate vortex rings, which are toroidal vortices formed by the jet's initial momentum. Here, we report high‐speed imaging and acoustic measurements of vortex rings sourcing from gas‐rich eruptive jets at Stromboli volcano (Italy). Volcanic vortex rings (VVRs) form at the vent together with an initial compression acoustic wave, VVRs maximum rise velocity being directly proportional to the amplitude and inversely proportional to the duration of the compression wave. The axial rise and acoustic signature of VVRs match well those predicted by recent fluid‐dynamic experiments. This good match allows using the high‐frequency (80–1,000 Hz) component of the jet sound and the time‐dependent rise of VVRs to retrieve two key eruption parameters: the Mach number of the eruptive jets (<1.5) and vent diameter (∼0.7 m), respectively, the latter being confirmed independently by direct Uncrewed Aerial Vehicle observations. Plain Language Summary: Vortex rings are donut‐shaped vortices that form when a jet of fluid from a nozzle enters a fluid reservoir, as exemplified well by smoke rings (smoke blown from a mouth into air). Explosive volcanic eruptions produce vortex rings when a mixture of gas and particles erupts in the atmosphere from a circular vent. Here, we used slow‐motion videos and microphone recordings to study the vortex rings produced by the explosions of Stromboli volcano, in Italy. Applying recent fluid‐dynamic experimental findings to our novel observations, we were able to measure two important but elusive parameters of the explosions: the diameter of the vent and the ratio between the velocity of the gas‐particle mixture and the velocity of sound in the mixture. These results improve our capability to model dangerous eruptions and monitor volcanoes by their sound. Key Points: Volcanic vortex rings are formed by gas‐rich, jet‐forming Strombolian‐style explosionsThe explosion acoustic signals bear the signature of the vortex rings and reveal supersonic eruptive jets with Mach number up to 1.5Vent diameter can be estimated from the time‐dependent rise of vortex rings at 0.7 m, in agreement with direct observation from Uncrewed Aerial Vehicle [ABSTRACT FROM AUTHOR]

Abstract: Quantitative ultrasound (QUS) is a reliable technique to evaluate skeletal status, to identify osteoporotic subjects, and to estimate the risk of fractures. The purpose of this study was to generate QUS normative data for Italian females and males aged 60–79yr participating in the Epidemiologic Study on the Prevalence of Osteoporosis (ESOPO) study, using the Achilles Plus apparatus. ESOPO is a cross-sectional study conducted in 2000, aiming at assessing risk of osteoporosis in a random sample of 11,011 women and 4981 men, representative of the Italian population. All participants were administered a questionnaire on the most relevant risk factors for osteoporosis and fractures; 3 QUS parameters were also measured: broadband ultrasound attenuation (BUA); speed of sound (SOS); and Stiffness Index (SI). We studied the age-dependent changes in QUS values, and their correlation with body size. For both men and women, weight was the variable with the highest correlation with BUA and SI; for SOS, age among women and body mass index (BMI) among men presented the highest correlation coefficients. Average decreases of 3.0% in BUA, 0.8% in SOS, and 9.1% in SI from 60 to 79yr were detected for females, whereas no significant changes with age in males were observed. Our data show lower QUS values for women, and a decline at a greater rate than in men. [Copyright &y& Elsevier]

Understanding acoustic velocities of sedimentary deposits is crucial for realistic subsurface imaging. The velocities rely on mineralogy, density, as well as pore volume (porosity) and pore structure. In carbonate rocks, both depositional and diagenetic histories exert a significant control on these characteristics. In order to determine this control, petrographic analysis (thin sections) associated with the analysis of the carbonate content, grain density, permeability, porosity, and acoustic measurements were performed on samples from Cretaceous to Eocene carbonate platform-to-basin series of Albania. Rock facies showed two depositional associations and four pore-type associations. Very low average permeability (<1 mD) and variable porosity values (0–14%) characterize the samples. Pore type and diagenetic alteration steered the porosity-permeability distribution. Modelling of the velocity-porosity relationship, using the differential effective medium theory (DEM), revealed that variations in the acoustic velocity were mainly driven by variations in porosity and pore type, while facies and mineralogy were of minor importance. The Albanian dataset was compared with petrophysical data retrieved from time- and deep-water facies equivalent carbonate series of the Gargano Promontory in Italy. The comparison demonstrates that the variation in acoustic velocity is limited within the Albanian samples due to the pronounced infill of primary and secondary pores. Acoustic velocity data, on the other hand, are more scattered for the Gargano and this is essentially related to the higher porosity due to the preserved primary macro-intergranular and micro-intercrystalline pores, and/or to significant development of secondary mouldic pores. This study contributes to the understanding of heterogeneities and spatial distribution of pore types resulting in different petrophysical signatures of Cretaceous platform to deep-water carbonates. The data provide a better insight into possible variations in reservoir quality and seismic signature of these types of carbonates in subsurface reservoirs. • Facies distribution of Cretaceous to Eocene carbonate platform-to-basin sediments in Albania. • Assess the depositional and diagenetic controls on pore space within a carbonate platform-to-basin setting. • Study the spatial distribution of rock properties of a carbonate platform-to-basin system. • Evaluate the impact of rock properties on the elastic behavior. [ABSTRACT FROM AUTHOR]

Abstract: Multi-model Super-Ensembles (SE) which optimally combine different models, have been shown to significantly improve atmospheric weather and climate predictions. In the highly dynamic coastal ocean, the presence of small-scales processes, the lack of real-time data, and the limited skill of operational models at the meso-scale have so far limited the application of SE methods for acoustic Rapid Environmental Assessment purposes. In the framework of the BP07 experiment conducted South East of Elba, sound speed prediction skills of various SE techniques combining operational model outputs and in-situ measurements are assessed. Results suggest that SE-based predictions provide more robust 24 h forecasts. A detailed acoustic propagation sensitivity study at different frequencies and ranges also reviews the potential of these predictions for acoustic inversion and tomography efforts. [Copyright &y& Elsevier]