Propagation of sound waves in air can be considered as a special case of fluid dynamics. Consequently, the lattice Boltzmann method (LBM) for fluid flow can be used for simulating sound propagation. In this article application of the LBM to sound propagation is illustrated for various cases: free-field propagation, propagation over porous and non-porous ground, propagation over a noise barrier,...

The afterglow emission that follows gamma-ray bursts (GRBs) contains valuable information about the circumburst medium and, therefore, about the GRB progenitor. Theoretical studies of GRB blast waves, however, are often limited to simple density profiles for the external medium (mostly constant density and power-law R−k ones). We argue that a large fraction of long-duration GRBs should take pla...

BACKGROUND It has been known for more than 20 years that the early aggregation of the slime mould Dictyostelium is driven by periodic waves of cAMP, which instruct the cells to collect at the aggregation centre. Although it has been hypothesized that cAMP waves are also involved in the organization of multicellular morphogenesis, wave propagation in the later stages of Dictyostelium development...

A hallmark of protein kinase/phosphatase cascades, including mitogen-activated protein kinase (MAPK) pathways, is the spatial separation of their components within cells. The top-level kinase, MAP3K, is phosphorylated at the cell membrane, and cytoplasmic kinases at sequential downstream levels (MAP2K and MAPK) spread the signal to distant targets. Given measured protein diffusivity and phospha...

We present an arbitrary-order spectral element method for general-purpose simulation of non-overturning water waves, described by fully nonlinear potential theory. The method can be viewed as a high-order extension of the classical finite element method proposed by Cai et al (1998) [5], although the numerical implementation differs greatly. Features of the proposed spectral element method inclu...

Similar to the Stokes drift in periodic gravity waves, we introduce a second-order effect on particle isolated linear surface disturbances (pulses) shallow water. For disturbance with shape and length scale of KdV solitary wave, model results agree surprisingly well observed moderately steep waves laboratory, as more comprehensive theory for waves.

Intercellular Ca(2+) waves are believed to propagate through networks of glial cells in culture in one of two ways: by diffusion of IP(3) between cells through gap junctions or by release of ATP, which functions as an extracellular messenger. Experiments were conducted to determine the mechanism of Ca(2+) wave propagation between glial cells in an intact CNS tissue. Calcium waves were imaged in...

the use of acoustic waves in researches related to sea water is of most importance among scientistsrecently. since these waves are the only waves, transmitted in water with lowest attenuation and high speed, they canbe used in many scientific fields. the main goal of this research is to better understand the physics and mechanismsof sound-seabed interaction, including acoustic penetration, prop...

We here describe intercellular calcium waves as a novel form of cellular communication among thymic epithelial cells. We first characterized the mechanical induction of intercellular calcium waves in different thymic epithelial cell preparations: cortical 1-4C18 and medullary 3-10 thymic epithelial cell lines and primary cultures of thymic "nurse" cells. All thymic epithelial preparations respo...

[1] Measurements of intrawave sediment entrainment processes are reported above ripples under irregular waves generated in a large‐scale flume facility. The data consist of substantive observations of small‐scale processes collected at high spatial and temporal resolution under irregular wave forcing, typical of coastal environments. Acoustic measurements were made of water velocities, bed form...