Most bacteria in the ocean can be motile. Chemotaxis allows bacteria to detect nutrient gradients, and hence motility is believed to serve as a method of approaching sources of food. This picture is well established in a stagnant environment. In the ocean a shear microenvironment is associated with turbulence. This shear flow prevents clustering of bacteria around local nutrient sources if they...

The rotational dynamics of anisotropic particles advected in a turbulent fluid flow are important in many industrial and natural settings. Particle rotations are controlled by small scale properties of turbulence that are nearly universal, and so provide a rich system where experiments can be directly compared with theory and simulations. Here we report the first three-dimensional experimental ...

a palatal defect may result from surgical resection, and its consequences could include difficulty in speech and nasal regurgitation of food and liquids. an obturator combined to speech aid prosthesis can improve nasal emission during speech,  and  assist  in  preventing  nasal  regurgitation  of  food.  this  article presents a clinical report of the reconstruction of palatopharyngeal function...

Planetesimal formation is a crucial yet poorly understood process in planet formation. It widely believed that planetesimal the outcome of dust clumping by streaming instability (SI). However, recent analytical and numerical studies have shown SI can be damped or suppressed external turbulence, at least outer regions protoplanetary disks are likely weakly turbulent due to magneto-rotational (MR...

Coarse resolution numerical ocean models must typically include a parameterisation for mesoscale turbulence. A common recipe for such parameterisations is to invoke mixing of some tracer quantity, such as potential vorticity or buoyancy. However, it is well known that eddy fluxes include large rotational components which necessarily do not lead to any mixing; eddy diffusivities diagnosed from u...

We study the structure and dynamics of active region magnetic loops at transition region temperatures by analyzing high resolution observations of the active region NOAA 7962 at the limb on 1996 May 6. During the decay phase of a B-class are which occurred at the active region, the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrograph on board the Solar and Heliospheric Obser...

In this paper, a nonlinear backstepping controller is proposed to manage the performance of full-variable permanent magnet synchronous generator wind turbine. This achieves rotational speed objective for and validated through Lyapunov-based stability analysis. Additionally, accomplished without measurement that influences torque. The scheme compared typical linear simulation results. Simulation...

in this research, the effect of micro turbulence on the flotation rate of quartz particles was investigated. the maximum particle reynolds number (rep) was obtained at 60.25 with a particle size of -500+420 µm, impeller speed of 900 rpm, bubble surface area flux of 10.21 1/s and micro scale turbulence size of 162 µm. when the micro turbulence size was equal to the particle size, the maximum flo...

The design and optimization of hydrocyclones using CFD techniques are gaining popularity and the key to a successful simulation lies with the accurate description of the high turbulent swirling behavior of the flow. This paper presents a detailed co...

Angular momentum is one of the most important physical quantities that governs star formation. The initial angular a core may be responsible for its fragmentation, and can have an influence on size protoplanetary disk. To understand how cores obtain their momentum, it to study filaments where they form. While theoretical studies filament rotation been explored, there exist very few observationa...