Two modes of motions for a single disk on the vibration stage.

The motion of a single granular particle is important for understanding their collective motions on vibration stage, but it remains poorly studied for simple shaped particles, such as a disk. Here, we systematically measure the motions of a single disk with different vibration amplitudesat a fixed vibration frequencyor a fixed acceleration. The distributions, time-correlations, and power spectra of displacements per step, mean squared displacements and couplings for translational and rotational motions are measured.

Experimental investigation of active noise on a rotor in an active granular bath.

In an active bath, besides thermal noise, immersed passive objects also persistently experience collisions from active particles, which are often coarse-grained into a colored active noise with an assumed exponential time correlation. The exponentially correlated active noise extremely simplifies the theoretical description of immersed passive objects but so far lacks direct experimental verification. Here, we experimentally investigate the active noise subjected by a passive rotor confined in an active granular bath.

A unified constitutive model for pressure sensitive shear flow transitions in moderate dense granular materials.

Granular shear flows exhibit complex transitional regimes that are dramatically affected by the pressure level and shear stress state. New advances in granular shear tests at low pressure have enlightened the understanding of the two granular shear flow transitions: between quasi-static and moderate shear flows, and between steady-state and transient shear flows. However, a unified constitutive model to describe these two transitions is yet to develop.

Dynamics of a vibration-driven single disk.

Granular particles exhibit rich collective behaviors on vibration beds, but the motion of an isolated particle is not well understood even for uniform particles with a simple shape such as disks or spheres. Here we measured the motion of a single disk confined to a quasi-two-dimensional horizontal box on a vertically vibrating stage. The translational displacements obey compressed exponential distributions whose exponent [Formula: see text] increases with the frequency, while the rotational displacements exhibit unimodal distributions at low frequencies and bimodal distributions at high frequencies.

Flow-induced surface crystallization of granular particles in cylindrical confinement.

An interesting phenomenon that a layer of crystallized shell formed at the container wall during an orifice flow in a cylinder is observed experimentally and is investigated in DEM simulation. Different from shear or vibration driven granular crystallization, our simulation shows during the flow the shell layer is formed spontaneously from stagnant zone at the base and grows at a constant rate to the top with no external drive. Roughness of the shell surface is defined as a standard deviation of the surface height and its development is found to disobey existed growth models.

Microscopic structure and dynamics study of granular segregation mechanism by cyclic shear.

Granular mixtures with size difference can segregate upon shaking or shear. However, the quantitative study of this process remains difficult because it can be influenced by many mechanisms. Conflicting results on similar experimental systems are frequently obtained when the experimental conditions are not well controlled, which is mainly due to the fact that many mechanisms can be at work simultaneously.

Brassinosteroids synthesised by CYP85A/A1 but not CYP85A2 function via a BRI1-like receptor but not via BRI1 in Picea abies.

Brassinosteroids (BRs) are essential plant hormones. In angiosperms, brassinolide and castasterone, the first and second most active BRs, respectively, are synthesised by CYP85A2 and CYP85A/A1, respectively. BRs in angiosperms function through an essential receptor, BR Insensitive 1 (BRI1).

Clinical research on stereotactic radiosurgery combined with epithermal growth factor tyrosine kinase inhibitors in the treatment of brain metastasis of non-small cell lung cancer.

Purpose: To compare the clinical efficacy and safety of stereotactic radiosurgery (SRS) combined with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) versus whole-brain radiation therapy (WBRT) combined with EGFR-TKIs in the treatment of brain metastasis of non-small cell Lung cancer (NSCLC).

Methods: The clinical data of patients with brain metastatic NSCLC who had EGFR-sensitive mutation and followed between January 2014 and January 2016 was retrospectively analyzed. Patients were divided into two groups according to their treatment types.

Coupled Leidenfrost states as a monodisperse granular clock.

Using an event-driven molecular dynamics simulation, we show that simple monodisperse granular beads confined in coupled columns may oscillate as a different type of granular clock. To trigger this oscillation, the system needs to be driven against gravity into a density-inverted state, with a high-density clustering phase supported from below by a gaslike low-density phase (Leidenfrost effect) in each column. Our analysis reveals that the density-inverted structure and the relaxation dynamics between the phases can amplify any small asymmetry between the columns, and lead to a giant oscillation.

Phase transition and flow-rate behavior of merging granular flows.

Merging of granular flows is ubiquitous in industrial, mining, and geological processes. However, its behavior remains poorly understood. This paper studies the phase transition and flow-rate behavior of two granular flows merging into one channel.

Construction of microsatellite-based linkage map and mapping of nectarilessness and hairiness genes in Gossypium tomentosum.

Gossypium tomentosum, a wild tetraploid cotton species with AD genomes, possesses genes conferring strong fibers and high heat tolerance. To effectively transfer these genes into Gossypium hirsutum, an entire microsatellite (simple sequence repeat, SSR)-based genetic map was constructed using the interspecific cross of G. hirsutum x G.

Hydrodynamics of granular gases with a two-peak distribution.

Vibrating walls, frequently employed to maintain the temperature (i.e., average velocity) in a granular gas, modify the system strongly, rendering it dissimilar to a molecular one in various aspects.

Gluing bifurcation and noise-induced hopping in the oscillatory phenomena of compartmentalized bidisperse granular gases.

Oscillatory phenomena of compartmentalized bidisperse granular gases are studied through experiments, molecular dynamics simulations, and a flux model [Mikkelsen et al., Phys. Rev.

Elastic waves in the presence of a granular shear band formed by direct shear.

The propagation of elastic waves in a box under direct shear, filled with glass beads and being sheared at constant rates, is studied experimentally and theoretically. The respective velocities are shown to be essentially unchanged from that in a static granular system under the same pressure and shear stress but without a shear band. Influence of shear band on sound behaviors are also briefly discussed.

Traveling shock front in quasi-two-dimensional granular flows.

While the density profile of a granular shock front can be obtained by the conventional treatment of supersonic fluids, its temperature profile is very different from that in ordinary shocks. We study the density and temperature profiles of a traveling granular shock generated by piling up metal spheres in a closed bottom quasi-two-dimensional channel. We successfully account for the temperature profile in the granular shock using a simple kinetic theory in terms of energy transfer from the mean flow direction to the transverse direction.

Depth dependence of vertical plunging force in granular medium.

Depth dependence of vertical plunging force in granular medium is studied experimentally by measuring the slow-pushing force of different size and shape objects intruding vertically into a granular bed. It is found that all of the force curves of fully immersed intruders have concave-to-convex transition. The depth dependence of the force turns from supralinear to sublinear.

Oscillatory phenomena of compartmentalized bidisperse granular gases.

Compartmentalized bidisperse granular gases are numerically studied. Molecular-dynamics simulations studying granular clock phenomenon in three dimensions are presented, which complement previously reported two-dimensional simulation results. A flux model for binary mixtures is found to give qualitative descriptions for the oscillations, with no undetermined parameters or functions.

Temperature oscillations in a compartmentalized bidisperse granular gas.

A granular clock is observed in a vertically vibrated compartmentalized granular gas composed of two types of grains with the same size. The dynamics of the clock is studied in terms of an unstable evaporation or condensation model for the granular gas. In this model, the temperatures of the two types of grains are considered to be different, and they are functions of the composition of the gas.

van der Waals-like phase-separation instability of a driven granular gas in three dimensions.

We show that the van der Waals-like phase-separation instability of a driven granular gas at zero gravity, previously investigated in two-dimensional settings, persists in three dimensions. We consider a monodisperse granular gas driven by a thermal wall of a three-dimensional rectangular container at zero gravity. The basic steady state of this system, as described by granular hydrodynamic equations, involves a denser and colder layer of granulate located at the wall opposite to the driving wall.