The Modified Direct Method (MDM) is an iterative mesh smoothing method for smoothing planar and surface meshes, which is developed from the non-iterative smoothing method originated by Balendran [1]. When smooth planar meshes, the performance of the MDM is effectively identical to that of Laplacian smoothing, for triangular and quadrilateral meshes; however, the MDM outperforms Laplacian smooth...

This article presents special quadrilateral quadratic refinement elements, which provide geometry and field continuity across Tjunctions where two elements are connected to one side of a larger quadrilateral. The main idea in element refinement is to place one or more nodes outside the element area and to modify element shape functions in order to maintain continuity at refinement edges. Specia...

The 3D meshing process begins with the definition of the outer geometry. With a CAD system and a 2d quadrilateral mesh generator, a closed all-quadrilateral mesh is obtained, which is the start point for the process that this communication describes. Once imposed the outer quadrilateral mesh, the connectivity between the inner elements becomes strongly conditioned. Following the guidelines of t...

Axillary neuropathy due to entrapment of the nerve in the quadrilateral space is seen rarely. Here, we describe a 24-year-old patient diagnosed with isolated axillary neuropathy that mimicked quadrilateral space syndrome. Quadrilateral or quadrangular space syndrome (QSS), first described by Cahill and Palmer in 1983, was defined as the entrapment of the distal branch of the axillary nerve and ...

We present Laguerre Voronoi based subdivision algorithms for the quadrilateral and hexahedral meshing of particle systems within a bounded region in two and three dimensions, respectively. Particles are smooth functions over circular or spherical domains. The algorithm first breaks the bounded region containing the particles into Voronoi cells that are then subsequently decomposed into an initi...

The accuracy and eeciency of the solution to numerical systems depends on the quality of the mesh used. Automatic mesh generation and adaptive reenement methods can, however, produce poor quality elements, even invalid elements, for quadrilateral or hexahedral mesh. We present an optimization-based approach for quadrilateral or hexahedral mesh untangling that maximizes the minimum area or volum...

A uniform finite element mesh rarely provides the best discretization of a domain to accommodate a solution with both optimal efficiency and minimal error. Mesh adaptation can approach a more optimal solution by accommodating regions of the mesh with higher or lower element density. Extensive attention has been given to mesh adaptation in both computational mechanics and computer graphics to pr...

Normal and almost normal surfaces are essential tools for algorithmic 3-manifold topology, but to use them requires exponentially slow enumeration algorithms in a high-dimensional vector space. The quadrilateral coordinates of Tollefson alleviate this problem considerably for normal surfaces, by reducing the dimension of this vector space from 7n to 3n (where n is the complexity of the underlyi...

Abstract Cancer is the leading cause of death worldwide. Current anticancer drugs involve various toxic side effects; efforts are ongoing to develop new anticancer agents especially from the screening of natural compounds. Present study investigated cytotoxic effects and mode of cell death induced by the Caspian cobra venom in some human cancer cell lines. Cytotoxic effects of snake venom toxin...

Abstract Cancer is the leading cause of death worldwide. Current anticancer drugs involve various toxic side effects; efforts are ongoing to develop new anticancer agents especially from the screening of natural compounds. Present study investigated cytotoxic effects and mode of cell death induced by the Caspian cobra venom in some human cancer cell lines. Cytotoxic effects of snake venom toxin...