878 resultados para supersymmetry phenomenology
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It is shown that the world volume field theory of a single D3-brane in a supergravity D3-brane background admits finite energy, and non-singular, Abelian monopoles and dyons preserving 1/2 or 1/4 of the N=4 supersymmetry and saturating a Bogomolnyi-type bound. The 1/4 supersymmetric solitons provide a world volume realization of string-junction dyons. We also discuss the dual M-theory realization of the 1/2 supersymmetric dyons as finite tension self-dual strings on the M5-brane, and of the 1/4 supersymmetric dyons as their intersections.
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We present a new model of sequential adsorption in which the adsorbing particles experience dipolar interactions. We show that in the presence of these long-range interactions, highly ordered structures in the adsorbed layer may be induced at low temperatures. The new phenomenology is manifest through significant variations of the pair correlation function and the jamming limit, with respect to the case of noninteracting particles. Our study could be relevant in understanding the adsorption of magnetic colloidal particles in the presence of a magnetic field.
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A new supersymmetric black hole solution of five-dimensional supergravity is presented. It has an event horizon of topology S1 X S2. This is the first example of a supersymmetric, asymptotically flat black hole of nonspherical topology. The solution is uniquely specified by its electric charge and two independent angular momenta. These conserved charges can be arbitrarily close, but not exactly equal, to those of a supersymmetric black hole of spherical topology.
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We consider vacuum solutions in M theory of the form of a five-dimensional Kaluza-Klein black hole cross T6. In a certain limit, these include the five-dimensional neutral rotating black hole (cross T6). From a type-IIA standpoint, these solutions carry D0 and D6 charges. We show that there is a simple D-brane description which precisely reproduces the Hawking-Bekenstein entropy in the extremal limit, even though supersymmetry is completely broken.
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It is shown that a IIA superstring carrying D0-brane charge can be "blown up", in a Minkowski vacuum background, to a (1/4)-supersymmetric tubular D2-brane, supported against collapse by the angular momentum generated by crossed electric and magnetic Born-Infeld fields. This supertube can be viewed as a world-volume realization of the sigma-model Q lump.
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Dans une perspective phénoménologique, le corps, les fonctions vitales, le mouvement déterminent un échange constant entre le sujet et le monde, entre soi et l'autre. La neurobiologie, de son côté, s'intéresse aux transformations biologiques liées à ces expériences, mais sa méthode est fort différente. Les auteurs proposent une réflexion sur la manière dont les découvertes de la neurobiologie interviennent pour mieux "comprendre" la dimension de la rencontre. La relation intersubjective est façonnée non seulement par les structures du fonctionnement mental, par le vécu du sujet, mais encore par la "danse" des postures et le mouvement des corps ; elle est enfin portée par le milieu culturel et social, par la nature de l'environnement. La construction des liens entre le patient et le thérapeute permet à chacun d'eux de cheminer vers un accomplissement de sa propre existence. In a phenomenological perspective, the body, the vital functions, the movements determine a constant exchange between the subject and the world, between self and the others. The neurobiology on its part, is interested in the biological transformations connected to these experiences but its method is quite different. The authors suggest to consider how the neurobiological discoveries help to get a better understanding of the dimension of the encounter. The intersubjective relationship is not only shaped by the structures of the mental functioning, by the subject's experiences, but also by the « dance » of the postures and movements of the body; it is nonetheless influenced by the cultural and social environment, as well as by the type of environment. The build-up of relationships between the therapist and the patient allows both of them to find a way to fulfillment of their own existence.
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We have included the effective description of squark interactions with charginos/neutralinos in the MadGraph MSSM model. This effective description includes the effective Yukawa couplings, and another logarithmic term which encodes the supersymmetry-breaking. We have performed an extensive test of our implementation analyzing the results of the partial decay widths of squarks into charginos and neutralinos obtained by using FeynArts/FormCalc programs and the new model file in MadGraph. We present results for the cross-section of top-squark production decaying into charginos and neutralinos.
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El trabajo parte de una consideración de la hermenéutica como filosofía que cuestiona el sentido de la experiencia en la configuración del mundo histórico-social e intenta mostrar conexiones entre el desarrollo de esta corriente y posibles aportaciones de la Fenomenología.El objetivo de la investigación es analizar la presencia de algunos motivos fenomenológicos en las actuales propuestas de superación del planteamiento hermenéutico elaborado por Gadamer y de raíz heideggeriana, atendiendo a algunos de los debates a los que ha dado lugar y destacando el interés del tema de la empatía en relación con el de la comprensión. Estas nociones indicarán formas específicas de abordar el problema de la experiencia en el contexto intersubjetivo del mundo social.
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Complex auditory hallucinations are often characterized by hearing voices and are then called auditory verbal hallucinations (AVHs). While AVHs have been extensively investigated in psychiatric patients suffering from schizophrenia, reports from neurological patients are rare and, in most cases, incomplete. Here, we characterize AVHs in 9 patients suffering from pharmacoresistant epilepsy by analyzing the phenomenology of AVHs and patients' neuropsychological and lesion profiles. From a cohort of 352 consecutively examined patients with epilepsy, 9 patients suffering AVHs were identified and studied by means of a semistructured interview, neuropsychological tests, and multimodal imaging, relying on a combination of functional and structural neuroimaging data and surface and intracranial EEG. We found that AVHs in patients with epilepsy were associated with prevalent language deficits and damage to posterior language areas and basal language areas in the left temporal cortex. Auditory verbal hallucinations, most of the times, consisted in hearing a single voice of the same gender and language as the patient and had specific spatial features, being, most of the times, perceived in the external space, contralateral to the lesion. We argue that the consistent location of AVHs in the contralesional external space, the prominence of associated language deficits, and the prevalence of lesions to the posterior temporal language areas characterize AVHs of neurological origin, distinguishing them from those of psychiatric origin.
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We present a nonequlibrium approach for the study of a flexible bilayer whose two components induce distinct curvatures. In turn, the two components are interconverted by an externally promoted reaction. Phase separation of the two species in the surface results in the growth of domains characterized by different local composition and curvature modulations. This domain growth is limited by the effective mixing due to the interconversion reaction, leading to a finite characteristic domain size. In addition to these effects, first introduced in our earlier work [ Phys. Rev. E 71 051906 (2005)], the important new feature is the assumption that the reactive process actively affects the local curvature of the bilayer. Specifically, we suggest that a force energetically activated by external sources causes a modification of the shape of the membrane at the reaction site. Our results show the appearance of a rich and robust dynamical phenomenology that includes the generation of traveling and/or oscillatory patterns. Linear stability analysis, amplitude equations, and numerical simulations of the model kinetic equations confirm the occurrence of these spatiotemporal behaviors in nonequilibrium reactive bilayers.
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Summary: Phenomenology and linguistics
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Hsp70s are conserved molecular chaperones that can prevent protein aggregation, actively unfold, solubilize aggregates, pull translocating proteins across membranes and remodel native proteins complexes. Disparate mechanisms have been proposed for the various modes of Hsp70 action: passive prevention of aggregation by kinetic partitioning, peptide-bond isomerase, Brownian ratcheting or active power-stroke pulling. Recently, we put forward a unifying mechanism named 'entropic pulling', which proposed that Hsp70 uses the energy of ATP hydrolysis to recruit a force of entropic origin to locally unfold aggregates or pull proteins across membranes. The entropic pulling mechanism reproduces the expected phenomenology that inspired the other disparate mechanisms and is, moreover, simple.
Resumo:
En nuestra exposición pretendemos hacer una aportación a la fundamentación de una fenomenología del dinero. Se parte del hecho de la comprensión preteórica del dinero como un "ente para", es decir, como un útil. En esta comprensión preteórica, el dinero es entendido siempre desde su teleología: el dinero es [algo que es] para comprar. Difícilmente se define el dinero desde la actitud preteórica como "algo para vender" o como "el resultado del esfuerzo de mi trabajo". El ser del dinero deviene, desde su vivencia cotidiana, inseparable del acto de compra, remarcando la naturaleza profundamente proyectiva de su esencia. Para captar esta naturaleza proyectiva del dinero, será necesario llevar a cabo una fenomenología del acto de compra. ¿Comprar¿ es obtener algo con dinero. Pero, ¿cómo es la cosa adquirida? No es una cosa cualquiera: es una mercancía. En descripciones fenomenológicas sucesivas se intentará mostrar cómo la descripción de la espacialidad y la temporalidad de la mercancía es esencial para comprender aquello que el dinero lleva a cabo con la espacialidad y temporalidad del mundo circundante.
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Heidegger, en el parágrafo séptimo de Ser y Tienzpo, reconoció que el valor de la fenomenología reside en ser una posibilidad. Pues bien, se trata de indagar qué sentido pueda tener tal afirmación. Para ello, se analiza el sentido de los conceptos clave del planteamiento husserliano, teniendo encuenta toda su evolución y viendo cómo, de alguna manera, desde ellos quedan posibilitados la consideración y el estudio de ámbitos que, en cierta medida, significaban la ruptura del idealismo egológico y conciencialista, abriéndose a paradigmas filosóficos en los que se incluyen nuevas caracterizaciones de la subjetividad.
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La respuesta de Ortega a la fenomenología fue el descubrimiento de la vida como la nueva realidad radical del pensamiento filosófico, el cual ya no se fundamentará ni en el yo (idealismo) ni en las cosas (realismo) sino en la conjunción del yo con las cosas, lo que llanamente se conoce como vivir. Bajo la apariencia de una formulación sencilla ["solo ofrezco, modi res considerandi, una nueva manera de ver las cosas"] planteó la reforma radical de la filosofía con innovaciones importantes, entre ellas una nueva concepción de las categorías. En este proyecto la obra de Husserl fue, para Ortega, el instrumento prodigioso para abordar con garantías la compleja y necesaria superación del idealismo dentro de una nueva época de lahistoria de la filosofía capaz de asumir como propios el realismo y el idealismo -aboliéndolos y a la vez conservándolos a la manera de la Aujhebung hegeliana-. Ortega reconoció su deuda con la fenomenología, manifestación pionera y genuina de un espléndido nivel de reflexión fecunda y creación rigurosa, a caballo entre los dos siglos modernos por antonomasia. Pero como su pensamiento no aspiraba a ser "solo" moderno al considerarse también heredero dellegado antiguolmedieval, abandonó la fenomenología (sin renunciar a su nivel de exigencia) interpretando su razón vital e histórica como lo opuesto a la reducción fenomenológica.