Generation of symmetric periodic orbits by a heteroclinic loop formed by two singular points and their invariant manifolds of dimension 1 and 2 in R3

In this paper we will find a continuous of periodic orbits passing near infinity for a class of polynomial vector fields in R3. We consider polynomial vector fields that are invariant under a symmetry with respect to a plane and that possess a “generalized heteroclinic loop” formed by two singular points e+ and e− at infinity and their invariant manifolds � and . � is an invariant manifold of dimension 1 formed by an orbit going from e− to e+, � is contained in R3 and is transversal to . is an invariant manifold of dimension 2 at infinity. In fact, is the 2–dimensional sphere at infinity in the Poincar´e compactification minus the singular points e+ and e−. The main tool for proving the existence of such periodic orbits is the construction of a Poincar´e map along the generalized heteroclinic loop together with the symmetry with respect to .

Symmetric periodic orbits near a heteroclinic loop in R3 formed by two singular points, a semistable periodic orbit and their invariant manifolds

In this paper we consider C1 vector fields X in R3 having a “generalized heteroclinic loop” L which is topologically homeomorphic to the union of a 2–dimensional sphere S2 and a diameter connecting the north with the south pole. The north pole is an attractor on S2 and a repeller on . The equator of the sphere is a periodic orbit unstable in the north hemisphere and stable in the south one. The full space is topologically homeomorphic to the closed ball having as boundary the sphere S2. We also assume that the flow of X is invariant under a topological straight line symmetry on the equator plane of the ball. For each n ∈ N, by means of a convenient Poincar´e map, we prove the existence of infinitely many symmetric periodic orbits of X near L that gives n turns around L in a period. We also exhibit a class of polynomial vector fields of degree 4 in R3 satisfying this dynamics.

Symmetric periodic orbits near a heteroclinic loop formed by two singular points and their invariant manifolds of dimension 1 and 2

In this paper we consider vector fields in R3 that are invariant under a suitable symmetry and that posses a “generalized heteroclinic loop” L formed by two singular points (e+ and e −) and their invariant manifolds: one of dimension 2 (a sphere minus the points e+ and e −) and one of dimension 1 (the open diameter of the sphere having endpoints e+ and e −). In particular, we analyze the dynamics of the vector field near the heteroclinic loop L by means of a convenient Poincar´e map, and we prove the existence of infinitely many symmetric periodic orbits near L. We also study two families of vector fields satisfying this dynamics. The first one is a class of quadratic polynomial vector fields in R3, and the second one is the charged rhomboidal four body problem.

Fachada solar como pieza singular de arquitectura sostenible

Articulo sobre la importancia de las energias renovables y su integración arquitectónica en el camino hacia una arquitectura sostenible. Descripción y evaluación del proyecto Fachada Solar SCHOTT Iberica.

El maltrato singular cualificado por razon de género. Debate acerca de su constitucionalidad

En la presente aportación se analiza la prosperabilidad de las cuestiones de inconstitucionalidad que en la fecha de publicación del artículo penden ante el Tribunal Constit ucional en referencia al art. 153.1 CP. Con la aprobación de la Ley Orgánica de medidas de protecció integral contra la violencia de género se incluyó en el referido precepto del texto punitivo un tipo cualificado de maltrato singular u ocasional cuando el sujeto pasivo sea esposa o ex-esposa, pareja o ex-pareja, aun sin convivencia, del maltratador, entre otros supuestos agravados. La inclusión de un delito en que tanto el sexo del sujeto pasivo como el del activo se hallan más o menos explicitados ha enerado el planteamiento de un rosario de cuestiones de inconstitucionalidad por parte de distintos órganos jurisdiccionales que están pendientes de resolución ante el Tribunal Constitucional. Dichas cuestiones plantean la posible inconstitucionalidad del art. 153.1 CP sobre la base de su posible contradicción con los arts. 10, 14 y 24.2 CP. En este trabajo se pretende salvar la constitucionalidad del precepto, sobre la base de los postulados del principio de conservación de las normas, con ayuda de una exégesis restrictiva del tipo.

Modelagem de proteínas por homologia

Modeling methods to derive 3D-structure of proteins have been recently developed. Protein homology-modeling, also known as comparative protein modeling, is nowadays the most accurate protein modeling method. This technique can produce useful models for about an order of magnitude more protein sequences than there have been structures determined by experiment in the same amount of time. All current protein homology-modeling methods consist of four sequential steps: fold assignment and template selection, template-target alignment, model building, and model evaluation. In this paper we discuss in some detail the protein-homology paradigm, its predictive power and its limitations.

Les dunes litorals, un paisatge singular en regressió

Escrit que vol donar a conèixer el medi dunar litoral amb l’objectiu de recomanar la seva protecció urgent

Projeto terapêutico singular no âmbito da saúde mental: uma experiência no curso de graduação em medicina

O Jardim Campo Belo, localizado no município de Campinas (SP), é um bairro de alta vulnerabilidade social e grande demanda por serviços de saúde, sendo a única oferta em saúde mental o matriciamento com outra unidade de saúde. Neste contexto, durante as disciplinas do segundo ano de Medicina, foi realizado um projeto de intervenção no Centro de Saúde, mediante acompanhamento em domicilio de pacientes usuários de psicotrópicos. Realizaram-se visitas quinzenais às casas de dez pacientes. Nestas visitas, trabalhou-se um roteiro semidirigido, em que se buscou conhecer as demandas de cada paciente. Alguns destes aumentaram os cuidados com a própria saúde, e num caso houve até suspensão do uso dos medicamentos psicotrópicos, em parceria com a equipe; em outros casos, as visitas serviram como válvula de escape social, tornando-se um espaço onde se ofertava atenção aos que estavam acostumados ao abandono social. Os alunos envolvidos relatam grande aprendizado graças às vivências e ao envolvimento com o tema, que se tornou um grande suplemento pedagógico.

Singular Reference Without Singular Thought

Abstract In this paper I challenge the widespread assumption that the conditions for singular reference are more or less the same as the conditions for singular thought. I claim that we refer singularly to things without thinking singularly about them more often than it is usually believed. I first argue that we should take the idea that singular thought is non-descriptive thought very seriously. If we do that, it seems that we cannot be so liberal about what counts as acquaintance; only perception (and memory) will do. I also briefly discuss and reject semantic instrumentalism. Finally, I argue that while singular reference is cheap, singular thought comes only at a price.

El pueblo queretano a su singular patrona María Santísima en su advocación del Pueblito.

UANL

Tratado unico y singular del origen de los indios del Perú, Méjico, Santa Fe y Chile

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