Derivation of an Abelian effective model for instanton chains in 3D Yang-Mills theory

In this work, we derive a recently proposed Abelian model to describe the interaction of correlated monopoles, center vortices, and dual fields in three dimensional SU(2) Yang-Mills theory. Following recent polymer techniques, special care is taken to obtain the end-to-end probability for a single interacting center vortex, which constitutes a key ingredient to represent the ensemble integration.Comment: 18 pages, LaTe

Facilitated spin models: recent and new results

Facilitated or kinetically constrained spin models (KCSM) are a class of interacting particle systems reversible w.r.t. to a simple product measure. Each dynamical variable (spin) is re-sampled from its equilibrium distribution only if the surrounding configuration fulfills a simple local constraint which \emph{does not involve} the chosen variable itself. Such simple models are quite popular in the glass community since they display some of the peculiar features of glassy dynamics, in particular they can undergo a dynamical arrest reminiscent of the liquid/glass transitiom. Due to the fact that the jumps rates of the Markov process can be zero, the whole analysis of the long time behavior becomes quite delicate and, until recently, KCSM have escaped a rigorous analysis with the notable exception of the East model. In these notes we will mainly review several recent mathematical results which, besides being applicable to a wide class of KCSM, have contributed to settle some debated questions arising in numerical simulations made by physicists. We will also provide some interesting new extensions. In particular we will show how to deal with interacting models reversible w.r.t. to a high temperature Gibbs measure and we will provide a detailed analysis of the so called one spin facilitated model on a general connected graph.Comment: 30 pages, 3 figure

Evidence of a Critical time in Constrained Kinetic Ising models

We study the relaxational dynamics of the one-spin facilitated Ising model introduced by Fredrickson and Andersen. We show the existence of a critical time which separates an initial regime in which the relaxation is exponentially fast and aging is absent from a regime in which relaxation becomes slow and aging effects are present. The presence of this fast exponential process and its associated critical time is in agreement with some recent experimental results on fragile glasses.Comment: 20 Pages + 7 Figures, Revte

Effect of light intensity and wavelength on concentration of plant secondary metabolites in the leaves of Flourensia cernua

Flourensia cernua (tarbush) is a shrub that has encroached into grasslands in many areas of the northern Chihuahuan Desert and contains high levels of carbon-based secondary compounds. Concentrations of secondary compounds are affected by numerous biotic and abiotic influences, including amount and wavelength of solar radiation. However, responses to shade and ultraviolet light restriction are inconsistent among plant species and compound class. We conducted a three-year study to evaluate the effect of shade and UV light restriction on total phenolic and terpene concentrations in tarbush. Sixty plants were randomly assigned to one of three treatments (control, UV light restriction, or 50% incident light restriction). Mean concentrations of total phenolics and total volatiles in tarbush were 82.4 and 12.5 mg/g DM, respectively. Total phenolics did not differ between UV-restricted and control plants, but were lower in shaded plants than the other treatments (P \u3c 0.05). Total volatiles tended to be greater for the UV-restricted treatment than control plants (P = 0.056), with shaded plants not different from either treatment. Treatment effects were detected for 18 individual compounds (P \u3c 0.05). Our results partially support the hypothesis that UV restriction and shading alter carbon-based secondary chemical concentrations

Singularities in ternary mixtures of k-core percolation

Heterogeneous k-core percolation is an extension of a percolation model which has interesting applications to the resilience of networks under random damage. In this model, the notion of node robustness is local, instead of global as in uniform k-core percolation. One of the advantages of k-core percolation models is the validity of an analytical mathematical framework for a large class of network topologies. We study ternary mixtures of node types in random networks and show the presence of a new type of critical phenomenon. This scenario may have useful applications in the stability of large scale infrastructures and the description of glass-forming systems.Comment: To appear in Complex Networks, Studies in Computational Intelligence, Proceedings of CompleNet 201

Effects of oxytocin administration on spirituality and emotional responses to meditation

The oxytocin (OT) system, critically involved in social bonding, may also impinge on spirituality, which is the belief in a meaningful life imbued with a sense of connection to a Higher Power and/or the world. Midlife male participants (N = 83) were randomly assigned to receive intranasal OT or placebo. In exploratory analyses, participants were also genotyped for polymorphisms in two genes critical for OT signaling, the oxytocin receptor gene (OXTR rs53576) and CD38 (rs6449182 and rs3796863). Results showed that intranasal OT increased self-reported spirituality on two separate measures and this effect remained significant a week later. It also boosted participants’ experience of specific positive emotions during meditation, at both explicit and implicit levels. Furthermore, the effect of OT on spirituality was moderated by OT-related genotypes. These results provide the first experimental evidence that spirituality, endorsed by millions worldwide, appears to be supported by OT