X iv :c on dm at /0 00 55 45 v1 [ co nd -m at .s tr -e l] 3 1 M ay 2 00 0 Plasma dispersion of multisubband electron systems over liquid helium Sviatoslav S. Sokolov Departamento de F́isica, Universidade Federal de São Carlos, 13565-905 São Carlos, São Paulo, Brazil and B. I. Verkin Institute for Low Temperature Physics and Engineering, National Academy of Sciences of Ukraine, 61164 Kharkov, Ukr...

Even a single-component liquid may have more than two liquid states. The transition between them is called a 'liquid-liquid transition' (LLT). Such LLTs have recently attracted considerable attention mainly because of the fundamental interest in the physical origin of this counter-intuitive phenomenon. In this study, we report the first observation of wetting effects on LLT for a molecular liqu...

The dynamics of swimming microorganisms is strongly affected by solid-liquid and air-liquid interfaces. In this paper, we characterize the motion of both single bacteria and microcolonies at an air-liquid interface. Both of them follow circular trajectories. Single bacteria preferentially show a counter-clockwise motion, in agreement with previous experimental and theoretical findings. Instead,...

Hydrodynamics has a strong influence on substrate elimination capacity in trickle-bed bioreactors (TBB). The present study reports the influence of liquid mass flow rate and bed void fraction on the TBB liquid residence time distribution (RTD), gas-liquid pressure drop, liquid hold-up, and biofilm wetting efficiency. Most RTD are well represented by a dispersion model. It is also shown that the...

Parametric amplification in semiconductor microcavities provides an example in which nonlinear optical interactions produced by the exchange interaction of excitons become so large that multiple scattering of polaritons becomes important. Here we review time-resolved observations of the polariton interactions in a number of different geometries including pumping at either the magic angle, or th...

A detailed study of the dispersion law of surface excitations in liquid 4He at zero temperature is presented, with special emphasis to the short wave length region. The hybridization mechanism between surface and bulk modes is discussed on a general basis, investigating the scattering of slow rotons from the surface. An accurate density functional, accounting for backflow effects, is then used ...

how to cite this article: movahedian ah, heidarzadeh arani m, motaharizad m, mousavi gha, mosayebi z. evaluation of qt dispersion in children with breath holding spells. iran j child neurol. winter 2016; 10(1):25-30. abstract objective breath holding spells (bhs) are common involuntary reflexes in infancy and early childhood. differential diagnosis should embrace long qt syndrome (lqts) and par...

The aggregation of magnetic particles in the presence of a magnetic field is the basic phenomenon which underlies all the physics of magnetorheological (MR) fluids. Although these interactions are well understood when the suspending fluid is a simple liquid, new MR fluids based on dispersion of magnetic microparticles in a ferrofluid or MR elastomers based on dispersion of magnetic particles in...

The role of stagnant zones in hydrodynamic dispersion is studied for creeping flow through a fixed bed of spherical permeable particles, covering several orders of characteristic time and length scales associated with fluid transport. Numerical simulations employ a hierarchical model to cope with the different temporal and spatial scales, showing good agreement with our experimental results on ...