Defect Formation Rates in Cosmological First-Order Phase Transitions

In cosmological first-order phase transitions, the progress of true-vacuum bubbles is expected to be significantly retarded by the interaction between the bubble wall and the hot plasma. It has been claimed that this leads to a significant reduction in the number of topological defects formed per bubble, as a result of phase equilibration between bubbles. This claim has been verified for spontaneously-broken global symmetries. We perform a series of simulations of complete phase transitions in the 2+1-dimensional U(1)-Abelian Higgs model, for a range of bubble wall velocities, in order to obtain a quantitative measure of the effect of bubble wall speed on the number density of topological defects. We find that the number of defects formed is i) significantly lower in the local than the global case and ii) decreases exponentially as a function of wall velocity. Slow-moving bubbles also lead, however, to the nucleation of more bubbles before the phase transition is complete. Our simulations show that this is in fact the dominant effect, and so we predict {\em more} defects per unit volume as a result of the sub-luminal bubble wall terminal velocity.Comment: 9 pages, 5 figures. Replaced with version to appear in Physical Review

ANALYSIS OF THE MUSCULAR INTERVENTION IN A BALLISTIC STRECHING EXERCISE BASED ON THE ANGULAR ACCELERATION AND EMG DATA

The aim of stretching exercises is to increase muscle-tendon flexibility which depends on neurogenic (stretch reflex), myogenic (viscoeiasticity of the musculo-tendinous structures) and joint constraints (Taylor et al. 1990; 1997). Among the other common techniques (passive, static and PNF) ballistic stretching is using the momentum of a moving body or a limb to force it beyond its normal range of motion. However, in spite of the exciting concerns of stretching neuromechanics, as well as, the overestimation of the role of connective tissue and the underestimation of the resistance of the muscles to stretch (Hutton, 1992), there is a lack of studies concerning the muscular activity in ballistic stretching. The main purpose of this study was to determine the intervention of the muscles quadriceps femoris (rectus femoris - vastus medialis) and biceps femoris and its relationship with the kinematics of the hip joint during a common ballistic stretching exercise

Familias y mujeres reagrupantes: un conflicto susceptible de mediación intercultural

En España, los y las inmigrantes pueden reagrupar a sus familias si cumplen una serie de requisitos. Según el personal funcionario encargado de la tramitación de estos expedientes, las dificultades aparecen cuando algunas mujeres no pueden cumplir las obligaciones establecidas, por lo cual se produce la privación de la situación de convivencia en familia. Comprendiendo la reagrupación o reunificación familiar como aquel derecho que tienen las personas no comunitarias que viven en España, a traer a cuantos ascendientes o descendientes tengan a su cargo, así como al cónyuge, siempre que cumplan ciertos requisitos y tales personas se encuentren en su país de origen en el momento en que el/la peticionario/a ejerza su derecho, no existen parámetros de igualdad entre hombres y mujeres inmigrantes si estos se encuentran basados en un modelo masculino de reagrupante. A modo de discriminación por razón de género, este conflicto favorece la exclusión social en detrimento de la integración social, efectiva y en igualdad, pretendida por los poderes públicos. Como problema social y extendiéndose las causas más allá del proceso administrativo, las situaciones conflictivas que viven estas mujeres exigen una acción colectiva y comunitaria

How does the geodesic rule really work for global symmetry breaking first order phase transitions?

The chain of events usually understood to lead to the formation of topological defects during phase transitions is known as the Kibble mechanism. A central component of the mechanism is the so-called ``geodesic rule''. Although in the Abelian Higgs model the validity of the geodesic rule has been questioned recently, it is known to be valid on energetic grounds for a global U(1) symmetry breaking transition. However, even for these globally symmetric models no dynamical analisys of the rule has been carried to this date, and some points as to how events proceed still remain obscure. This paper tries to clarify the dynamics of the geodesic rule in the context of a global U(1) model. With an appropriate ansatz for the field modulus we find a family of analytical expressions, phase walls, that accounts for both geodesic and nongeodesic configurations. We then show how the latter ones are unstable and decay into the former by nucleating pairs of defects. Finnally, we try to give a physical perspective of how the geodesic rule might really work in these transitions.Comment: 10 pages, 9 multiple figre

Guia y desengaño de artifices plateros y mercadores de oro y plata : en el cual se prescribe la obligacion de los fabricantes plateros en preparar la materias del oro y plata antes de construir con ellas las obras... fundado en la R. Pragmatica de 28 de febrero 1730 y ordenanzas y R. Cedula de 8 de agosto 1732 del Colegio de Plateros de Barcelona...

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-2010Fecha de la dedicatoria, 1743Port. con orla tip

Effect of topical application of melatonin on serum levels of C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in patients with type 1 or type 2 diabetes and periodontal disease

Background: The present clinical trial study was designed to assess the effect of topical application of melatonin on serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP) in patients with diabetes and periodontal disease in comparison with healthy controls. Material and Methods: Serum levels of TNF-α and IL-6 were measured by enzyme-linked immunosorbent assay and CRP by nephelometry by using the proper commercial kits in 30 patients with diabetes and periodontal disease, and also in a control group of 30 healthy subjects. Periodontograms were performed using the Florida Probe®. Patients with diabetes were treated with a topical application of melatonin (1% orabase cream formula) once daily for 20 days. Healthy subjects were treated with a placebo orabase cream. Results: Patients with diabetes and periodontal disease had significantly higher mean levels of serum TNF-α, IL-6 and CRP than healthy subjects ( P < 0.001). Following topical melatonin application, there was a statistically signi - ficant decrease in the gingival index and pocket depth ( P < 0.001) as well as a significant decrease in IL-6 and CRP serum levels ( P < 0.001). Local melatonin application in patients with diabetes and periodontal disease resulted in a significant decrease in CRP and IL-6 serum levels as well as an improvement in the gingival index and pocket depth. Patients with periodontal disease had significantly higher serum CRP, IL-6 and TNF-α values by comparison with healthy subjects. Conclusions: We conclude that melatonin can modulate the inflammatory action of these molecules in periodontal patient