Early work on proteins identified the existence of helices and extended sheets in protein secondary structures, a high-level classification which remains popular today. Using the Snob program for information-theoretic Minimum Message Length (MML) classification, we are able to take the protein dihedral angles as determined by X-ray crystallography, and cluster sets of dihedral angles into group...

A novel method for coherent broadband direction of arrival (DOA) estimation is introduced based on physics of signal propagation. This technique does not require any preliminary knowledge of DOA angles nor the number of sources to be estimated. As an illustration, two simulation examples covering single and multi-group scenarios are presented.

Studies of angular distributions and CP-violating observables in Bs → J/ψφ decays yield a space of parameters which can be considerably reduced if relative strong phases among different amplitudes are specified. We show that the relations between Bs → J/ψφ and B → J/ψK amplitudes given by flavor symmetry [actually U(3) rather than SU(3)] are likely to be quite reliable, and hence the use of str...

Polyhedra are an important basic structure in computational geometry. One of the most beautiful results concerning polyhedra is Cauchy’s theorem, which states that a convex polyhedron is uniquely defined by its graph, edge lengths and facial angles. (See Section 2 for definitions.) The proof of Cauchy’s theorem (see e.g. [2]) unfortunately is nonconstructive, and the only known algorithm to rec...

Background/aim: A current consensus in epidemiological studies of primary angle closure (PAC) is to diagnose the condition only if the posterior (usually pigmented) trabecular meshwork is seen for less than 90 ̊ of the angle circumference, termed an ‘‘occludable angle.’’ The authors sought to assess the validity of this epidemiological classification by exploring the relation between drainage an...

Abstract: The classification of the dihedral folding tessellations of the sphere and the plane whose prototiles are a kite and an equilateral triangle were obtained in a recent paper, [1]. Concerning to isosceles triangles the classification is much harder, which is not surprising since more angles are involved. In this paper we extend this classification presenting all the dihedral folding tes...

A spherical quadrilateral is a bordered surface homeomorphic to a closed disk, with four distinguished boundary points called corners, equipped with a Riemannian metric of constant curvature 1, except at the corners, and such that the boundary arcs between the corners are geodesic. We discuss the problem of classification of these quadrilaterals and perform the classification up to isometry in ...