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Context. Streaming instability is a key mechanism in planet formation, clustering pebbles into planetesimals with the help of self-gravity. It is triggered at a particular disk location where the local volume density of solids exceeds that of the gas. After their formation, planetesimals can grow into protoplanets by feeding from other planetesimals in the birth ring as well as by accreting inward

The results from a new numerical method for simulating the strength and fracture locations of small glass specimens subjected to double ring bending are compared with experimental data. The method implements the weakest-link principle while assuming the existence of Griffith flaws. A Weibull distribution for the strength is simulated based on a single population of Pareto distributed crack sizes.

The applicability of the Weibull distribution to model the strength of glass, the existence of a size effect on the strength and the need for a non-destructive testing of the strength are discussed and reviewed. There are a growing number of studies that put into question the applicability of the Weibull distribution to model annealed glass fracture data. A recent study indicates that the breakage

A numerical method is applied to model the fracture stress and failure location in glass panes subjected to various bending arrangements. The method assumes the weakest-link principle and the existence of surface microcracks. The fracture stress and failure origin are revealed through a search algorithm. The magnitude of strength and the location of fracture are stochastic in nature and can be pre

Observations find a median star formation efficiency per free-fall time in Milky Way Giant Molecular Clouds (GMCs) of the order of ϵff∼1 per cent with dispersions of ∼0.5dex⁠. The origin of this scatter in ϵff is still debated and difficult to reproduce with analytical models. We track the formation, evolution and destruction of GMCs in a hydrodynamical simulation of a Milky Way-like galaxy and by

Modelling the propagation of supernova (SN) bubbles, in terms of energy, momentum, and spatial extent, is critical for simulations of galaxy evolution which do not capture these scales. To date, small-scale models of SN feedback predict that the evolution of above-mentioned quantities can be solely parametrized by average quantities of the surrounding gas, such as density. However, most of these s

We use cosmological hydrodynamic zoom simulations to study the neutral gas distributionin and around galaxies that gives rise to high column density HILyαabsorption (dampedLyαsystems (DLAs) and sub-DLAs) in background quasar spectra. Such simulations oftensacrifice numerical resolution for volume that affects the lower density galaxy halo gas,and simulations have difficulties reproduci

We investigate the origin of the period distribution of giant planets. We fit the bias-corrected distribution of gas-giant planets inside 300 d found by Santerne et al. using a planet formation model based on pebble accretion. We investigate two possible initial conditions: a linear distribution of planetary seeds, and seeds injected exclusively on the water and CO icelines. Our simulations exclud

The processes that led to the formation of the planetary bodies in the Solar system are still not fully understood. Using the results obtained with the comprehensive suite of instruments onboard the European Space Agency's Rosetta mission, we present evidence that comet 67P/Churyumov-Gerasimenko likely formed through the gentle gravitational collapse of a bound clump of mm-sized dust aggregates ('

The terrestrial planets and the asteroids dominant in the inner asteroid belt are water poor. However, in the protoplanetary disk the temperature should have decreased below water-condensation level well before the disk was photo-evaporated. Thus, the global water depletion of the inner Solar System is puzzling. We show that, even if the inner disk becomes cold, there cannot be direct condensation

It has been shown that after production of oxophlorin, the first step of intermediate, both production of biliverdin and production of verdoheme occur simultaneously (Alavi et al. in Dalton Trans 47:8283–8291, 2018). So the mechanism that converts biliverdin into verdoheme is the subject of some controversy. The detailed conversion of verdo

Intrinsically disordered proteins (IDPs) can form functional oligomers and in some cases, insoluble disease related aggregates. It is therefore vital to understand processes and mechanisms that control pathway distribution. Divalent cations including Zn2+ can initiate IDP oligomerisation through the interaction with histidine residues but the mechanisms of doing so are far from understood. Here we

Stochastic radiation radar (SRR) systems allow for the forming of radar images by transmitting stochastic signals to form the stochastic radiation field and thereby increase the target observation information to achieve high resolution imaging. In this paper, we examine the use of the online SParse Iterative Covariance-based Estimation (SPICE) algorithm to suppress the noise and improve the operat