Circadian rhythmic processes, mainly regulated by gene expression at the molecular level, have inherent stochasticity. Their robustness or resistance to internal noise has been extensively investigated by most of the previous studies. This work focuses on the constructive roles of internal noise in a reduced Drosophila model, which incorporates negative and positive feedback loops, each with a ...

using the highly recommended numerical techniques, a finite element computer code is developed to analyse the steady incompressible, laminar and turbulent flows in 2-d domains with complex geometry. the petrov-galerkin finite element formulation is adopted to avoid numerical oscillations. turbulence is modeled using the two equation k-ω model. the discretized equations are written in the form o...

Abstract The dynamics of a phase inclusion in coaxial liquid layer divided with radial partition is studied experimentally. working volume the container filled viscous liquid, inside which an air bubble, immiscible main phase, injected. This has lower density than surrounding does. performs rotational oscillations as whole zero average rotation. Such motion brings to generation harmonically osc...

In paper the problem of reflection and refraction a plane harmonic sound wave by homogeneous isotropic elastic plate with an continuously inhomogeneous anisotropic coating is considered. It assumed that adjoin to ideal fluids. The propagation small perturbations in fluid case steady state oscillations described Helmholtz’s equation. waves uniform scalar vector equations for longitudinal transve...

cAMP-response element binding (CREB) proteins are involved in transcriptional regulation in a number of cellular processes (e.g., neural plasticity and circadian rhythms). The CREB family contains activators and repressors that may interact through positive and negative feedback loops. These loops can be generated by auto- and cross-regulation of expression of CREB proteins, via CRE elements in...

Switches (bistability) and oscillations (limit cycle) are omnipresent in biological networks. Synthetic genetic networks producing bistability and oscillations have been designed and constructed experimentally. However, in real biological systems, regulatory circuits are usually interconnected and the dynamics of those complex networks is often richer than the dynamics of simple modules. Here w...

Shedding of vortices is a common phenomenon in the atmosphere over a wide range of spatial and temporal scales. However, it is unclear how these vortices of varying scales affect the flight performance of flying animals. In order to examine these interactions, we trained seven hawkmoths (Manduca sexta) (wingspan ~9 cm) to fly and feed in a wind tunnel under steady flow (controls) and in the von...

The residual distribution framework was developed as an alternative to the finite volume approach for approximating hyperbolic systems of conservation laws which would allow a natural representation of genuinely multidimensional flow features. The resulting algorithms are closely related to conforming finite elements, but their structure makes it far simpler to construct nonlinear approximation...

Exact, fully explicit, purely real analytical expressions for the material functions describing steady, startup, and cessation regimes of shear flows planar, uniaxial, biaxial extensional full linear Phan-Thien--Tanner fluids are obtained. These expressions, which have no analogs in literature, formulated compact, beautiful forms, partially due to unique scaling procedure reducing number model ...