9,197 research outputs found
Four-dimensional gravity on supersymmetric dilatonic domain walls
We investigate the localization of four-dimensional metastable gravity in
supersymmetric dilatonic domain walls through massive modes by considering
several scenarios in the model. We compute corrections to the Newtonian
potential for small and long distances compared with a crossover scale given in
terms of the dilatonic coupling. 4D gravity behavior is developed on the brane
for distance very much below the crossover scale, while for distance much
larger, the 5D gravity is recovered. Whereas in the former regime gravity is
always attractive, in the latter regime due to non-normalizable unstable
massive graviton modes present on the spectrum, in some special cases, gravity
appears to be repulsive and signalizes a gravitational confining phase which is
able to produce an inflationary phase of the Universe.Comment: 11 pages, 4 figures, Latex. Version to appear in PL
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Eosinophilic dermatosis of hematologic malignancy: a case report
Eosinophilic dermatosis of hematologic malignancy (EDHM) is a dermatosis characterized by tissue eosinophilia that has been previously reported as insect bite-like reaction. It is a rare condition with a wide variety of clinical presentations ranging from papules, nodules, or blisters that simulate arthropod bites, to the formation of plaques of differing sizes. We report a case of eosinophilic dermatosis of hematologic malignancy in a patient with a hematoproliferative disorder
Analytical Multi-kinks in smooth potentials
In this work we present an approach which can be systematically used to
construct nonlinear systems possessing analytical multi-kink profile
configurations. In contrast with previous approaches to the problem, we are
able to do it by using field potentials which are considerably smoother than
the ones of Doubly Quadratic family of potentials. This is done without losing
the capacity of writing exact analytical solutions. The resulting field
configurations can be applied to the study of problems from condensed matter to
brane world scenarios
Teachers' presence and their influence on significant learning: Toward a mindfulness approach in education
Indexación: Scopus; Scielo.Este artículo realiza una revisión teórica de las últimas investigaciones en relación a mindfulness en educación, especialmente relacionada con los aportes de esta práctica para el cuidado docente y para el cultivo de una presencia más plena por parte de los profesores y su influencia en la totalidad del proceso formativo, poniendo especial énfasis en el cultivo de algunas actitudes: atencionales (no juicio, mente de principiante y esfuerzo justo) y relacionales (amabilidad, empatía y compasión). A partir de la revisión de importantes investigaciones recientes, este trabajo propone un modelo cuyo propósito es orientar distintas intervenciones basadas en lo que en este trabajo llamamos un “enfoque mindfulness”, enfatizando la necesidad de su carácter sistémico, más allá de eventos puntuales, con el propósito de influir en la totalidad del sistema educativo hacia una cultura del bienestar.This article presents a theoretical review of the recent research related to mindfulness in education, specifically that concerned with the contribution of this practice to the self-care of teachers and with how the cultivation of a fuller presence by teachers influences the formative process overall, putting special emphasis in the cultivation of certain attitudes: attentional (non-judgment, beginner’s mind, and right effort) and relational (kindness, empathy, and compassion) attitudes. In this way, the study carries out a rigorous review of pertinent research and proposes a guiding model for diverse interventions based on what we call “mindfulness focus,” emphasizing the need for a systemic view, beyond isolated events, with the purpose of influencing the education system overall toward a culture of well-being.https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0718-07052018000100241&lng=en&nrm=iso&tlng=e
Effective potential in Lorentz-breaking field theory models
We calculate explicitly the one-loop effective potential in different
Lorentz-breaking field theory models. First, we consider a Yukawa-like theory
and, then, some examples of Lorentz-violating extensions of scalar QED. We
observed, for the extended QED models, that the resulting effective potential
converges to the known result in the limit in which Lorentz-symmetry is
restored. Besides, the one-loop corrections to the effective potential in all
the cases we studied depend on the background tensors responsible for the
Lorentz symmetry violation. This have consequences in physical quantities like,
for example, in the induced mass due to Coleman-Weinberg mechanism.Comment: Version accepted for publication in EPJ
Universal scaling dynamics in a perturbed granular gas
We study the response of a granular system at rest to an instantaneous input
of energy in a localised region. We present scaling arguments that show that,
in dimensions, the radius of the resulting disturbance increases with time
as , and the energy decreases as , where the
exponent is independent of the coefficient of restitution. We
support our arguments with an exact calculation in one dimension and event
driven molecular dynamic simulations of hard sphere particles in two and three
dimensions.Comment: 5 pages, 5 figure
Cosmology in the Universe with distance dependent Lorentz-violating bakground
We consider a cosmological setup with the inflaton field in the presence of a
redshift dependent Lorentz-violating time-like background to address the
inflationary regime and other phases of the Universe. We also show that the
regime of dark energy at large distances (low redshifts) is essentially
dominated by the presence of the Lorentz-violating background.Comment: 8 pages, no figure, Latex, to appear in AHE
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