Mixing solutions for the Muskat problem

We prove the existence of mixing solutions of the incompressible porous media equation for all Muskat type $H^5$ initial data in the fully unstable regime.Comment: 88 pages, 2 figure

Beltrami equations with coefficient in the Sobolev space W1,p

We study the removable singularities for solutions to the Beltrami equation ∂f = µ ∂f, where µ is a bounded function, kµk∞ ≤ K−1 K+1 < 1, and such that µ ∈ W1,p for some p ≤ 2. Our results are based on an extended version of the well known Weyl's lemma, asserting that distributional solutions are actually true solutions. Our main result is that quasiconformal mappings with compactly supported Beltrami coefficient µ ∈ W1,p, 2K2 K2+1 < p ≤ 2, preserve compact sets of σ-finite length and vanishing analytic capacity, even though they need not be bilipschitz

Las enfermedades populares en la cultura española actual

Cabe suponer que cuando se goza de acceso universal a la sanidad, como sucede en la España contemporánea, la creencia en enfermedades populares termina desapareciendo. Sin embargo, una investigación de campo, desarrollada en el Suroeste de Andalucía en la primavera de 2004, indica que aún resta en la generalidad de la población un considerable conocimiento de un cierto número de enfermedades populares, y en concreto de la denominada «Mal de ojo». A partir de los datos obtenidos mediante un grupo de discusión con mujeres que curan estas enfermedades, la realización de una serie de entrevistas a personas o bien muy familiarizadas con el Mal de ojo, o bien profanas en esta enfermedad pero que creen en ella, y finalmente una revisión de materiales de archivo. Este artículo describe un modelo actual explicativo del Mal de ojo y propone algunas hipótesis sobre la pervivencia de la creencia en esta y otras enfermedades populares.It might be assumed that in a situation of universal access to biomedical health care, as is the case in contemporary Spain, folk illness beliefs would have vanished. Field research conducted in the spring of 2004 in Andalusia showed considerable knowledge in the general population about a number of folk illnesses, including mal de ojo (evil eye). Based on a focus group conducted with traditional healers, as well as in-depth interviews with specialists in mal de ojo, in-depth interviews with lay people who believe in this illness, and review of archival materials, this paper describes the contemporary explanatory model of mal de ojo and offers some hypotheses as to why beliefs in this illness, and other folk illnesses, persist

G-convergence, Dirichlet to Neumann maps and invisibility

We establish optimal conditions under which the G-convergence of linear elliptic operators implies the convergence of the corresponding Dirichlet to Neumann maps. As an application we show that the approximate cloaking isotropic materials from [19] are independent of the source

Gerald Brenan's Rocío, an epistolary autoethnography

En este artículo queremos presentar y contextualizar la carta inédita de Gerald Brenan a su amigo Ralph Partridge, en la que describe su vívida experiencia de la romería del Rocío de 1958. Por una feliz coincidencia Brenan acudió al Rocío en uno de los años más cruciales de su larga historia, cuando se iniciaba el proceso de rápida expansión, más conocido por masificación, de esta famosa romería. La descripción de Brenan de este ritual andaluz por excelencia resulta doblemente interesante. De un lado, por la ausencia de buena parte de los elementos de una etnografía convencional, de los que sí se había valido en 'Al Sur de Granada', publicado un año antes. De otro, por el convincente y gozoso relato de su pasajero triunfo sobre las miserias del envejecimiento, una especie de fugaz liberación de sí mismo en este escenario ideal.In this article we seek to show and contextualize Gerald Brenan’s unpublished letter to his friend Ralph Partridge, describing his vivid experience of the Romería del Rocío in 1958. By a fortuitous coincidence Brenan participated in El Rocío during one of the most pivotal years of its lengthy history, just as the famous romería began the process of rapid expansion known as the masificación. Brenan’s description of this quintessential Andalusia ritual is notable both for the absence of much of the conventional ethnography that he contributed to in 'South from Granada', published only a year before, as well as for its compelling and joyful depiction of his temporary triumph over the depredations of advancing age, a kind of fleeting liberation from his self in this ideal setting.- Grupo de investigación Antropología y Filosofía (SEJ-126). Universidad de Granada. - Área de Antropología Social. Universidad de Jaén. - Laborarorio de Antropología Social y Cultural (HUM-472). Universidad de Almería. - Departamento de Filosofía II. Universidad de Granada

Auditory Motion Information Drives Visual Motion Perception

BACKGROUND: Vision provides the most salient information with regard to the stimulus motion. However, it has recently been demonstrated that static visual stimuli are perceived as moving laterally by alternating left-right sound sources. The underlying mechanism of this phenomenon remains unclear; it has not yet been determined whether auditory motion signals, rather than auditory positional signals, can directly contribute to visual motion perception. METHODOLOGY/PRINCIPAL FINDINGS: Static visual flashes were presented at retinal locations outside the fovea together with a lateral auditory motion provided by a virtual stereo noise source smoothly shifting in the horizontal plane. The flash appeared to move by means of the auditory motion when the spatiotemporal position of the flashes was in the middle of the auditory motion trajectory. Furthermore, the lateral auditory motion altered visual motion perception in a global motion display where different localized motion signals of multiple visual stimuli were combined to produce a coherent visual motion perception. CONCLUSIONS/SIGNIFICANCE: These findings suggest there exist direct interactions between auditory and visual motion signals, and that there might be common neural substrates for auditory and visual motion processing

Las yeguas marismeñas de Doñana: naturaleza, tradición e identidades sociales en un espacio protegido

The breeding of Andalusia's feral marsh horses stands out among other examples of Doñana National Park's extraordinary legacy of social and cultural traditions. This is so not only because of its importance as a venerable livestock management system, unique and vibrant still despite being surprisingly little known and scarecly studied, but also because it constitutes a notable example of the contributions that Andalusian culture has made to the rest of the world. Marsh animal husbandry is, without a doubt, the cultural matrix out of which developed the livestock traditions of the Americas. By situating this cultural complex within an International comparative framework, we argue that the human involvement with Doñana's feral horses may be distinguished from other similar cases in the world because their care and maintenance has been converted, to an extraordinary degree, into a central element of the local culture. Highly emotional social processes are involved in the construction and maintenance of a collective social identity that expresses itself in perennial conflicts with the authorities of the Park over its feral horses.Entre el extraordinario legado de tradiciones sociales y culturales del Parque Nacional de Doñana (Suroeste de Andalucía) sobresale la cría de caballos marismeños asilvestrados, no sólo por su importancia como práctica ganadera ancestral, viva e insólita, sorprendentemente poco conocida y apenas estudiada, sino también porque constituye un ejemplo eminente de las contribuciones de la cultura andaluza al resto del mundo. La ganadería marismeña es, sin duda, la matriz cultural de las tradiciones ganaderas de América. En este artículo se aborda su análisis dentro de un marco comparativo internacional del que se deduce que lo que verdaderamente distingue la cría de los caballos marismeños de otros casos paralelos en el mundo es haberse convertido en un elemento central de la cultura local, mediante emotivos procesos sociales de construcción y mantenimiento de la identidad comunitaria, en medio de reiterados conflictos con las autoridades oficiales del Parque

Las yeguas marismeñas de Doñana : naturaleza, tradición e identidades sociales en un espacio protegido

Entre el extraordinario legado de tradiciones sociales y culturales del Parque Nacional de Doñana (Suroeste de Andalucía) sobresale la cría de caballos marismeños asilvestrados, no sólo por su importancia como práctica ganadera ancestral, viva e insólita, sorprendentemente poco conocida y apenas estudiada, sino también porque constituye un ejemplo eminente de las contribuciones de la cultura andaluza al resto del mundo. La ganadería marismeña es, sin duda, la matriz cultural de las tradiciones ganaderas de América. En este artículo se aborda su análisis dentro de un marco comparativo internacional del que se deduce que lo que verdaderamente distingue la cría de los caballos marismeños de otros casos paralelos en el mundo es haberse convertido en un elemento central de la cultura local, mediante emotivos procesos sociales de construcción y mantenimiento de la identidad comunitaria, en medio de reiterados conflictos con las autoridades oficiales del Parque

Lack of uniqueness for weak solutions of the incompressible porous media equation

In this work we consider weak solutions of the incompressible 2-D porous media equation. By using the approach of De Lellis-Sz\'ekelyhidi we prove non-uniqueness for solutions in $L^\infty$ in space and time.Comment: 23 pages, 2 fugure

Interaction of perceptual grouping and crossmodal temporal capture in tactile apparent-motion

Previous studies have shown that in tasks requiring participants to report the direction of apparent motion, task-irrelevant mono-beeps can &quot;capture'' visual motion perception when the beeps occur temporally close to the visual stimuli. However, the contributions of the relative timing of multimodal events and the event structure, modulating uni- and/or crossmodal perceptual grouping, remain unclear. To examine this question and extend the investigation to the tactile modality, the current experiments presented tactile two-tap apparent-motion streams, with an SOA of 400 ms between successive, left-/right-hand middle-finger taps, accompanied by task-irrelevant, non-spatial auditory stimuli. The streams were shown for 90 seconds, and participants' task was to continuously report the perceived (left-or rightward) direction of tactile motion. In Experiment 1, each tactile stimulus was paired with an auditory beep, though odd-numbered taps were paired with an asynchronous beep, with audiotactile SOAs ranging from -75 ms to 75 ms. Perceived direction of tactile motion varied systematically with audiotactile SOA, indicative of a temporal-capture effect. In Experiment 2, two audiotactile SOAs-one short (75 ms), one long (325 ms)-were compared. The long-SOA condition preserved the crossmodal event structure (so the temporal-capture dynamics should have been similar to that in Experiment 1), but both beeps now occurred temporally close to the taps on one side (even-numbered taps). The two SOAs were found to produce opposite modulations of apparent motion, indicative of an influence of crossmodal grouping. In Experiment 3, only odd-numbered, but not even-numbered, taps were paired with auditory beeps. This abolished the temporal-capture effect and, instead, a dominant percept of apparent motion from the audiotactile side to the tactile-only side was observed independently of the SOA variation. These findings suggest that asymmetric crossmodal grouping leads to an attentional modulation of apparent motion, which inhibits crossmodal temporal-capture effects