This paper presents facts related to the explosion accident that occurred on August 12, 2015, in Tianjin Port, China. Two serious explosions occurred continuously. Six large fire points and dozens of ...small ones occurred, and they resulted in heavy casualties and property losses. This paper discusses the catastrophe, causes, and related emergency response.
Highlights • Kir4.1 ( KCNJ10 ) is required for EP and spiral ganglion function in the inner ear. • Deficiency of Kir4.1 causes deafness with EAST or SeSAME syndromes. • Deafness mutants show “loss of ...function” and can be rescued by WT isoform. • Deafness mechanisms of Kir4.1 deficiency are discussed and prospected.
Context.
Surveys of protoplanetary disks in star-forming regions of similar age revealed significant variations in average disk mass in some regions. For instance, disks in the Orion Nebular Cluster ...(ONC) and Corona Australis (CrA) are on average smaller than disks observed in Lupus, Taurus, Chamaeleon I, or Ophiuchus.
Aims.
In contrast to previous models that studied the truncation of disks at a late stage of their evolution, we investigate whether disks may already be born with systematically smaller disk sizes in more massive star-forming regions as a consequence of higher ionization rates.
Methods.
Assuming various cosmic-ray ionization rates, we computed the resistivities for ambipolar diffusion and Ohmic dissipation with a chemical network, and performed 2D nonideal magnetohydrodynamical protostellar collapse simulations.
Results.
A higher ionization rate leads to stronger magnetic braking, and hence to the formation of smaller disks. Accounting for recent findings that protostars act as forges of cosmic rays and considering only mild attenuation during the collapse phase, we show that a high average cosmic-ray ionization rate in star-forming regions such as the ONC or CrA can explain the detection of smaller disks in these regions.
Conclusions.
Our results show that on average, a higher ionization rate leads to the formation of smaller disks. Smaller disks in regions of similar age can therefore be the consequence of different levels of ionization, and may not exclusively be caused by disk truncation through external photoevaporation. We strongly encourage observations that allow measuring the cosmic-ray ionization degrees in different star-forming regions to test our hypothesis.
Abstract
We describe the algorithm used to select the emission line galaxy (ELG) sample at z ∼ 0.85 for the extended Baryon Oscillation Spectroscopic Survey of the Sloan Digital Sky Survey IV, using ...photometric data from the DECam Legacy Survey. Our selection is based on a selection box in the g − r versus r − z colour–colour space and a cut on the g-band magnitude, to favour galaxies in the desired redshift range with strong
${{\rm O}\,\small {II}}$
emission. It provides a target density of 200 deg−2 on the North Galactic Cap and of 240 deg−2 on the South Galactic Cap (SGC), where we use a larger selection box because of deeper imaging. We demonstrate that this selection passes the extended Baryon Oscillation Spectroscopic Survey requirements in terms of homogeneity. About 50 000 ELGs have been observed since the observations have started in 2016, September. These roughly match the expected redshift distribution, though the measured efficiency is slightly lower than expected. The efficiency can be increased by enlarging the redshift range and with incoming pipeline improvement. The cosmological forecast based on these first data predict
$\sigma _{D_V}/D_V = 0.023$
, in agreement with previous forecasts. Lastly, we present the stellar population properties of the ELG SGC sample. Once observations are completed, this sample will be suited to provide a cosmological analysis at z ∼ 0.85, and will pave the way for the next decade of massive spectroscopic cosmological surveys, which heavily rely on ELGs. The target catalogue over the SGC will be released along with DR14.
The majority of stars are part of gravitationally bound stellar systems, such as binaries. Observations of protobinary systems constrain the conditions that lead to stellar multiplicity and ...subsequent orbital evolution. We report high-angular resolution observations of the circumbinary disk around BHB2007 11, a young binary protostar system. The two protostars are embedded in circumstellar disks that have radii of 2 to 3 astronomical units and probably contain a few Jupiter masses. These systems are surrounded by a complex structure of filaments connecting to the larger circumbinary disk. We also observe accretion and radio jets associated with the protobinary system. The accretion is preferentially onto the lower-mass protostar, consistent with theoretical predictions.
Nepal is one of the most earthquake-prone areas in the world. This country is located in the Himalayan tectonic belt and the subduction and collision border of the Indian Ocean and Eurasian Plates. ...Given its special geological feature, quakes are extremely frequent in this area. An 8.1-magnitude tremor hit Nepal on April 25, 2015, which is the fifth magnitude 8 earthquake that occurred on land in this century. This earthquake caused numerous casualties and severe destruction. From a Chinese perspective, this article provides a brief introduction into the catastrophe, the emergency response that follows, and several related reflections.
Understanding fluid flow in granular materials is essential for many engineering applications, including petroleum recovery, groundwater movement and embankment stability. This study investigates the ...influence of particle angularity on permeability and fluid-particle interaction forces. A random shape generator based on spherical harmonics is used to create irregular-shaped particles with different levels of angularity. Granular packings of uniformly sized (monodisperse) particles are then constructed with the discrete element method (DEM), and pore-scale computational fluid dynamics (CFD) simulations are used to determine the flow fields and the resulted fluid-particle interaction. The more angular particle assemblies thus generated are less permeable, and their fluid-particle interaction forces are higher. However, angularity has limited influence on flow rate distribution and flow tortuosity. The influence of angularity is localized. An increase in angularity generates a larger variance of the pressure distribution on the particle surfaces, thus increasing the pressure component of the fluid-particle interaction force.
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•A framework to generate dense packings of angular particles is proposed.•Flow in packings of uniform angular particles is simulated with pore-scale CFD.•Influence of particle angularity on permeability is quantified.•Detailed statistical analysis is performed on fluid-particle interactions.•Particle-to-particle variance of fluid-particle interactions is analyzed.
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