This paper presents an automated tool for local, conformal refinement of all-hexahedral meshes based on the insertion of multidirectional twist planes into the spatial twist continuum. The refinement process is divided into independent refinement steps. In each step, an inserted twist plane modifies a single sheet or two parallel hex sheets. Six basic templates, chosen and oriented based on the...

Ascidian larvae develop mesenchyme cells in their trunk. A fibroblast growth factor (FGF9/16/20) is essential and sufficient for induction of the mesenchyme in Ciona savignyi. We have identified two basic helix-loop-helix (bHLH) genes named Twist-like1 and Twist-like2 as downstream factors of this FGF. These two genes are phylogenetically closely related to each other, and were expressed specif...

Introduction Left ventricular (LV) twist is believed to store potential energy and plays an important role in generating diastolic suction. Recent advances in echocardiography techniques have allowed quantification of LV twist. The aim of the present study was to compare LV twist and torsion in healthy human subjects determined by velocity vector imaging (VVI) and tissue Doppler imaging (TDI) a...

Members of the Twist-family of bHLH proteins play a pivotal role in a number of essential developmental programs. Twist-family bHLH proteins function by dimerizing with other bHLH members and binding to cis- regulatory elements, called E-boxes. While Twist-family members may simply exhibit a preference in terms of high-affinity binding partners, a complex, multilevel cascade of regulation creat...

An ensemble of screws is known as a screw system, and is deened by a set of n 6 independent basis screws. The order of a screw system is equal to the number of basis screws required to deene it; such a system is also called an n-system. The order of a screw system reciprocal to an n-system is (6 ? n). With an innnitesimal rigid motion of an object in three-dimensional Euclidean space there is a...

The aim of the present study is to determine the feasibility of making a rectangular twist waveguide used to rotate electromagnetic waves. For this purpose, the process of fabricating an aluminum rectangular twist waveguide was simulated by making use of finite element method and Deform software. The optimum length and angle of the twist die for manufacturing a twist waveguide with inner cross ...

Because of the double-helical structure of DNA, in which two strands of complementary nucleotides intertwine around each other, a covalently closed DNA molecule with no interruptions in either strand can be viewed as two interlocked single-stranded rings. Two closed space curves have long been known by mathematicians to exhibit a property called the linking number, a topologically invariant int...

We consider the usual one-pile subtraction game with an extra feature, called a Muller twist. The twist is that the number of stones to be removed from the heap is dictated by our opponent to be either in a prescribed set S or not. We investigate regularity in the sequences of Grundy values for such games.