We perform spin-dynamics SD simulations to study the field induced incommensurate-to-commensurate phase transition for the spiral antiferromagnet Ba2CuGe2O7. Under an increasingly applied magnetic field, we find that the system undergoes a transition from a two-dimensional 2D spiral state to a spin-flop state, passing through an intermediate phase. The simulations identify two order parameters ...

We find equilibrium configurations of open and closed lines of charge on a sphere, and track them with respect to varying sphere radius. Closed lines transition from a circle to a spiral-like shape through two low-wave-number bifurcations-"baseball seam" and "twist"-which minimize Coulomb energy. The spiral shape is the unique stable equilibrium of the closed line. Other unstable equilibria ari...

OBJECTIVES The great arteries are in a non-spiral relationship in their transposition, even after arterial switch operation (ASO) with the Lecompte manoeuvre. We aim to restore the natural spiral great arteries and compare such ASO with conventional ASO with the Lecompte manoeuvre to clarify the functional implications of the spiral great arteries. METHODS The early survivors of ASO (n=130) w...

In this paper we examine spiral structures in bi-parametric diagrams of dissipative systems with strange attractors. First, we show that the organizing center for spiral structures in a model with the Shilnikov saddle-focus is related to the change of the structure of the attractor transitioning between the spiral and screw-like types located at the turning point of a homoclinic bifurcation cur...

We present an algorithm for generating G 1-continuous spiral-like tool paths for machining pockets without islands. The pocket may be an arbitrary simply-connected 2D shape bounded by straight-line segments and circular arcs. Based on the Voronoi diagram of the pocket we generate a sequence of nested Jordan curves (“wave fronts”) inside the pocket that are linked to form a spiral-like tool path...

Spiral waves in excitable media possess both wave-like and particle-like properties. When resonantly forced (forced at the spiral rotation frequency) spiral cores travel along straight trajectories, but may reflect from medium boundaries. Here, numerical simulations are used to study reflections from two types of boundaries. The first is a no-flux boundary which waves cannot cross, while the se...

conclusion spiral-ct scan is superior to conventional ct in the diagnosis of lesions in com before operation. it can be used for detailed evaluation of ossicular chain in such patients. objectives this study was performed to compare the findings of three-dimensional reconstructed spiral and conventional ct scan of ossicular chain study in patients with com. patients and methods fifty patients e...