Results 11 to 20 of about 85,172 (262)
On the multiplicity of umbilic points
Pacific Journal of Mathematics, 2022 We introduce an invariant of umbilic points on surfaces in the Euclidean or Minkowski 3-space that counts the maximum number of stable umbilic points they can split up under deformations of the surfaces. We call that number the multiplicity of the umbilic point and establish its properties.
do Couto Fernandes, Marco Antônio +1 more
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On isolated umbilic points [PDF]
Communications in Analysis and Geometry, 2020 Counter-examples to the famous conjecture of Caratheodory, as well as the bound on umbilic index proposed by Hamburger, are constructed with respect to Riemannian metrics that are arbitrarily close to the flat metric on Euclidean 3-space. In particular, Riemannian metrics with a smooth strictly convex 2-sphere containing a single umbilic point are ...
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A metric property of umbilic points [PDF]
Anais da Academia Brasileira de Ciências, 2003 In the space of cubic forms of surfaces, regarded as a G-space and endowed with a natural invariant metric, the ratio of umbilic points with a negative index to those with a positive index is evaluated in terms of the asymmetry of the metric, defined here.
Garcia, Ronaldo, Sotomayor, Jorge
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Bifurcations of Umbilic Points and Related Principal Cycles [PDF]
Journal of Dynamics and Differential Equations, 2004 The simplest patterns of qualitative changes on the configurations of lines of principal curvature} around umbilic points on surfaces whose immersions into $\mathbb R^3$ depend smoothly on a real parameter (codimension one umbilic bifurcations) are described in this paper. Global effects, due to umbilic bifurcations, on these configurations such as the
Gutiérrez, Carlos +2 more
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Perestroikas of vertex sets at umbilic points [PDF]
Functional Analysis and Other Mathematics, 2008 Mark all vertices on a curve evolving under a family of curves obtained by intersecting a smooth surface M with the 1-parameter family of planes parallel to the tangent plane to M at a point p. Those vertices trace out a set, called the vertex set of M through p. We take p to be an isolated umbilic point on M and describe the perestroikas of the vertex
Capitanio, Gianmarco, Diatta, André
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On the patterns of principal curvature lines around a curve of umbilic points [PDF]
Anais da Academia Brasileira de Ciências, 2005 In this paper is studied the behavior of principal curvature lines near a curve of umbilic points of a smooth surface.
Garcia, Ronaldo, Sotomayor, Jorge
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On parabolic and umbilic points of immersed hypersurfaces [PDF]
Transactions of the American Mathematical Society, 1967 Introduction. This paper is a natural sequel to Geometry of immersions. I and II ([1] and [2]). The object is to apply the general geometric singularity theory developed in [1] and [2] to two specific geometric singularities of an immersed n manifold in R'+ll.
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Ethical issues relating the the banking of umbilical cord blood in Mexico
BMC Medical Ethics, 2009 Background Umbilical cord banks are a central component, as umbilical cord tissue providers, in both medical treatment and scientific research with stem cells.
Valdez-Martinez Edith +2 more
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Foot & Ankle Orthopaedics, 2021 Background: For hallux rigidus, dorsal cheilectomy remains a treatment option even with advances in interposition techniques and devices. Cheilectomy aims to alleviate dorsal impingement and improve pain and function as well as range of motion ...
Sara Heintzman Galli MD +7 more
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Animals, 2023 The aim of the study was to compare the analgesic efficacy of tramadol and lidocaine for local anesthesia during umbilical hernia repair in swine. The study was performed on 66 large white crossbred swine.
Giovanna Lucrezia Costa +13 more
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