Combining several previously known arguments, we prove marked length spectrum rigidity for surfaces with nonpositively curved Riemannian metrics away from a finite set of cone-type singularities with cone angles > 2π. With an additional condition, we can weaken the requirement on one metric to ‘no conjugate points.’

Fish larvae, like most adult fish, undulate their bodies to propel themselves. A detailed kinematic study of the larval body wave is a prerequisite to formulate a set of functional requirements that the locomotor system must fulfil to generate the observed swimming kinematics. Lateral displacement and curvature profiles were obtained for zebrafish (Danio rerio) larvae at 2-21 days post-fertilis...

The perceived angular velocity of an ellipse undergoing a constant rate of rotation will vary as its aspect ratio is changed. Specifically, a "fat" ellipse with a low aspect ratio will in general be perceived to rotate more slowly than a "thin" ellipse with a higher aspect ratio. Here we investigate this illusory underestimation of angular velocity in the domain where ellipses appear to be rota...

The aim of this study was to investigate the association of axial length (AL)/corneal radius of curvature (CRC) ratio (AL/CRC) with spherical equivalent refractive state (SER) in young adults. A total of seventy (n = 70) subjects consisting of 31 males and 39 females participated in this study. Subjects were categorized into emmetropia, hyperopia and myopia using the spherical equivalent refrac...

A finite element model was used to study the dielectric constant and breakdown strength of polymer composite filled with high aspect ratio fillers. The impact of composite microstructure and filler aspect ratio on the dielectric properties was investigated. The results were used to explain the experimental data for BaTiO3 fiber filled poly(dimethyl siloxane) published previously. The effect of ...

In this paper, we show that an $L_1$-2-type surface in the three-dimensional hyperbolic space $H^3subset R^4_1$ either is an open piece of a standard Riemannian product $ H^1(-sqrt{1+r^2})times S^{1}(r)$, or it has non constant mean curvature, non constant Gaussian curvature, and non constant principal curvatures.

materials and methods: one hundred and thirty five mesial root canals of mandibular first and second molar teeth were selected. access cavities were prepared. after inserting a k-file size #10 into each canal, radiographs were taken. canal curvature was determined by measuring the schneider angle, canal access angle, as well as the canal radius, length, height and curvature starting distance on...

i ntroduction: the aim of this study was to compare the shaping ability of two single-file systems and conventional rotary instruments in severely curved root canals of extracted human molars. methods and materials: mesiobuccal canals of 120 mandibular molars with angles of curvature ranging between 25 ° and 35 ° and radii of curvature from 5 to 9 mm, were divided into three groups ( n =40). in...

although, most of the abnormal structures of human brain do not alter the shape of outer envelope of brain (surface), some abnormalities can deform the surface extensively. however, this may be a major problem in a surface-based registration technique, since two nearly identical surfaces are required for surface fitting process. a type of verification known as the circularity check for the shap...

introduction: the objective of this study was to compare the shaping ability of three rotary filing systems; constant taper k3 instruments, constant taper profile instruments and progressive taper protaper rotary instruments in clear resin blocks with simulated curved root canals. materials and methods: forty five resin blocks were divided into three groups. group a preparation was conducted wi...