Context. Observational evidence indicates that the orbits of extrasolar planets are more various than the circular and coplanar ones of the Solar system. Planet-planet interactions during migration in the protoplanetary disc have been invoked to explain the formation of these eccentric and inclined orbits. However, our companion paper (Paper I) on the planet-disc interactions of highly inclined and eccentric massive planets has shown that the damping induced by the disc is significant for a massive planet, leading the planet back to the midplane with its eccentricity possibly increasing over time. Aims. We aim to investigate the influence of the eccentricity and inclination damping due to planet-disc interactions on the final configurations of the systems, generalizing previous studies on the combined action of the gas disc and planet-planet scattering during the disc phase. Methods. Instead of the simplistic K-prescription, our n-body simulations adopt the damping formulae for eccentricity and inclination provided by the hydrodynamical simulations of our companion paper. We follow the orbital evolution of 11000 numerical experiments of three giant planets in the late stage of the gas disc, exploring different initial configurations, planetary mass ratios and disc masses. Results. The dynamical evolutions of the planetary systems are studied along the simulations, with a particular emphasis on the resonance captures and inclination-growth mechanisms. Most of the systems are found with small inclinations (≤ 10• ) at the dispersal of the disc. Even though many systems enter an inclination-type resonance during the migration, the disc usually damps the inclinations on a short timescale. Although the majority of the multiple systems in our simulations are quasi-coplanar, ∼ 5% of them end up with high mutual inclinations (≥ 10• ). Half of these highly mutually inclined systems result from two-or three-body mean-motion resonance captures, the other half being produced by orbital instability and/or planet-planet scattering. When considering the long-term evolution over 100 Myr, destabilization of the resonant systems is common, and the percentage of highly mutually inclined systems still evolving in resonance drops to 30%. Finally, the parameters of the final system configurations are in very good agreement with the semi-major axis and eccentricity distributions in the observations, showing that planet-planet interactions during the disc phase could have played an important role in sculpting planetary systems.
This study examined the development of peak handgrip strength from childhood to adulthood in wrestlers (n = 122) and nonathlete controls (n = 122). The effect of hand preference on handgrip strength and the relationship of anthropometrical characteristics with handgrip strength in wrestlers and controls were also evaluated. Participants were assigned into age groups: children, young adolescents, late adolescents, and adults. Body height and mass, hand dimensions (length, span, and width), and absolute handgrip (in kilograms) were measured. Handgrip strength was similar in wrestlers and controls in the younger age groups (i.e., in children and young adolescents), whereas late adolescent and adult wrestlers exhibited significantly greater peak handgrip strength (p < 0.05) than their control peers. Nonathletes older than 15 years demonstrated an approximately 10% greater peak handgrip strength (p < 0.05) with their preferred hand compared with the nonpreferred hand. In contrast, late adolescent and adult wrestlers exhibited similar handgrip strength with both hands. Peak handgrip strength exhibited a significant linear correlation with all the anthropometric measures examined; however, a higher percentage in the variation in peak handgrip strength was explained by body height and hand length than the other anthropometric variables in both groups. In conclusion, wrestlers exhibit a sport-specific pattern of handgrip strength changes during the developmental years. Body height and hand length exhibited the strongest correlations with handgrip strength during the developmental years in wrestlers and in controls. The training adaptations of wrestling resulted in symmetrical handgrip strength development in both hands at late adolescence and adulthood. These data serve to provide a descriptive profile of handgrip strength in wrestlers, to assist both coaches and health professionals for talent selection and/or development of training programs for performance enhancement and rehabilitation.
The late-stage formation of giant planetary systems is rich in interesting dynamical mechanisms. Previous simulations of three giant planets initially on quasi-circular and quasi-coplanar orbits in the gas disc have shown that highly mutually inclined configurations can be formed, despite the strong eccentricity and inclination damping exerted by the disc. Much attention has been directed to inclination-type resonance, asking for large eccentricities to be acquired during the migration of the planets. Here we show that inclination excitation is also present at small to moderate eccentricities in two-planet systems that have previously experienced an ejection or a merging and are close to resonant commensurabilities at the end of the gas phase. We perform a dynamical analysis of these planetary systems, guided by the computation of planar families of periodic orbits and the bifurcation of families of spatial periodic orbits. We show that inclination excitation at small to moderate eccentricities can be produced by (temporary) capture in inclination-type resonance and the possible proximity of the non-coplanar systems to spatial periodic orbits contributes to maintaining their mutual inclination over long periods of time.
We investigate the inclination-growth mechanisms for two-planet systems during the late protoplanetary disc phase. In previous works, much attention has been directed to the inclination-type resonance, and it has been shown that it asks for high eccentricities to be acquired during the migration of the giant planets. By adopting eccentricity and inclination damping formulae based on hydrodynamical simulations (instead of the K-prescription), we have carried out 20000 numerical simulations, where we vary the initial planetary eccentricities, the migration rate, and the dispersal time of the gas disc. Our results confirm that highly mutually inclined systems are unlikely to be produced by an inclination-type resonance of two migrating giant planets. However, in $\sim 1~\%$ of the simulations, inclination-type resonance is observed, and a dynamical study of the evolutions reveals that the inclination-type resonance mechanism operates in three cases: i) when the inner planet reaches the inner cavity of the disc, ii) at moderate to high eccentricities for faster migration rates, and iii) at low to moderate eccentricities after a phase of orbital destabilization and re-arrangement.
Photocatalytic inactivation of pathogens in aqueous waste is gaining increasing attention. Several homogeneous and heterogeneous photocatalytic protocols exist using the Fenton’s reagent and TiO2, respectively. A comprehensive study of homogeneous and heterogeneous photocatalysis on a range of microorganisms will significantly establish the most efficient method. Here, we report a comparative study of TiO2- and Fe+3-based photocatalytic inactivation under UV-A of diverse microorganisms, including Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, bacterial spores (Bacillus stearothermophilus spores) and viruses (MS2). We also present data on the optimization of TiO2 photocatalysis, including optimal catalyst concentration and H2O2 supplementation. Our results indicate that both photo-Fenton and TiO2 could be successfully applied for the management of microbial loads in liquids. Efficient microorganism inactivation is achieved with homogeneous photocatalysis (7 mg/L Fe+3, 100 mg/L H2O2, UV-A) in a shorter processing time compared to heterogeneous photocatalysis (0.5 g/L TiO2, UV-A), whereas similar or shorter processing is required when heterogenous photocatalysis is performed using microorganism-specific optimized TiO2 concentrations and H2O2 supplementation (100 mg/L); higher H2O2 concentrations further enhance the heterogenous photocatalytic inactivation efficiency. Our study provides a template protocol for the design and further application for large-scale photocatalytic approaches to inactivate pathogens in liquid biomedical waste.
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