String effects in SU(2) lattice gauge theory

We discuss the effective string picture for the confining regime of lattice gauge theories at zero and finite temperature. We present results of extensive Monte Carlo simulations - performed with the Luscher and Weisz algorithm - for SU(2) Yang-Mills theory in 2+1 dimensions. We also address the issue of "string universality" by comparing our results with those obtained in other lattice gauge theories.Comment: 3 pages, 2 figures, Lattice2003(topology

Efecto del cambio climático sobre problemas fitosanitarios en caña de azúcar, maní y algodón: un abordaje binacional.

La roya marrón y la roya anaranjada de la caña de azúcar, la viruela tardía del maní y el picudo del algodonero son problemas fitosanitarios actuales y potenciales para estos cultivos industriales tanto en Argentina como en Brasil. En Argentina no se han realizado estudios sobre el efecto del cambio climático en cultivos que ocupan actualmente áreas bien definidas, con perspectivas de expandirse a otras áreas agroecológicas, generando flujos de patógenos y plagas en macroregiones abarcando ambos países. Para ello se elaboró un proyecto interinstitucional entre INTA y EMBRAPA cuyo objetivo principal es evaluar el impacto del cambio climático sobre enfermedades y plagas de cultivos de importancia para la agroindustria de Argentina y Brasil, intentando el desarrollo de alternativas de adaptación para su control en los escenarios climáticos futuros. La investigación y discusión en red entre Argentina y Brasil es una oportunidad indispensable para evitar esfuerzos innecesarios, integrando los resultados obtenidos con los diferentes cultivos de importancia para la agroindustria

Relativistic gravitational collapse in comoving coordinates: The post-quasistatic approximation

A general iterative method proposed some years ago for the description of relativistic collapse, is presented here in comoving coordinates. For doing that we redefine the basic concepts required for the implementation of the method for comoving coordinates. In particular the definition of the post-quasistatic approximation in comoving coordinates is given. We write the field equations, the boundary conditions and a set of ordinary differential equations (the surface equations) which play a fundamental role in the algorithm. As an illustration of the method, we show how to build up a model inspired in the well known Schwarzschild interior solution. Both, the adiabatic and non adiabatic, cases are considered.Comment: 14 pages, 11 figures; updated version to appear in Int. J. Modern Phys.

Finite temperature results on the 2d Ising model with mixed perturbation

A numerical study of finite temperature features of thermodynamical observables is performed for the lattice 2d Ising model. Our results support the conjecture that the Finite Size Scaling analysis employed in the study of integrable perturbation of Conformal Field Theory is still valid in the present case, where a non-integrable perturbation is considered.Comment: 9 pages, Latex, added references and improved introductio

Boundary and Interface CFTs from the Conformal Bootstrap

40 pages, many figures v2: new results on 3d O(N) bulk spectrum added, one appendix eliminated, typos corrected, references updated. v3: two references to high precision Monte Carlo data added; they nicely agree with our bootstrap calculations. Matches published version. v4: results for the extraordinary transition for N=2,3 removed: see added noteWe explore some consequences of the crossing symmetry for defect conformal field theories, focusing on codimension one defects like flat boundaries or interfaces. We study surface transitions of the 3d Ising and other O(N) models through numerical solutions to the crossing equations with the method of determinants. In the extraordinary transition, where the low-lying spectrum of the surface operators is known, we use the bootstrap equations to obtain information on the bulk spectrum of the theory. In the ordinary transition the knowledge of the low-lying bulk spectrum allows to calculate the scale dimension of the relevant surface operator, which compares well with known results of two-loop calculations in 3d. Estimates of various OPE coefficients are also obtained. We also analyze in 4-epsilon dimensions the renormalization group interface between the O(N) model and the free theory and check numerically the results in 3d

Wilson Loops in string duals of Walking and Flavored Systems

We consider the VEV of Wilson loop operators by studying the behavior of string probes in solutions of Type IIB string theory generated by Nc D5 branes wrapped on an internal manifold. In particular, we focus on solutions to the background equations that are dual to field theories with a walking gauge coupling as well as for flavored systems. We present in detail our walking solution and emphasize various general aspects of the procedure to study Wilson loops using string duals. We discuss the special features that the strings show when probing the region associated with the walking of the field theory coupling.Comment: 28 pages. Various figures. Version to be published

Alexithymia, impulsiveness, and psychopathology in Nonsuicidal self-injured adolescents

Introduction: Nonsuicidal self-injury (NSSI) is a multifaceted phenomenon and a major health issue among adolescents. A better understanding of self-injury comorbidities is crucial to improve our ability to assess, treat, and prevent NSSI. Purpose: This study aimed at analyzing some of the psychobehavioral correlates of NSSI: psychological problems, alexithymia, impulsiveness, and sociorelational aspects. Patients and methods: This was a case-control study. The clinical sample (n=33) included adolescents attending our unit for NSSI and other issues; the controls (n=79) were high-school students. Data were collected using six questionnaires: Youth Self-Report, Barratt\u2019s Impulsiveness Scale, Toronto Alexithymia Scale, Children\u2019s Depression Inventory, Symptom Checklist-90-R, and Child Behavior Checklist. Results: Cases scored significantly higher in all questionnaires. Habitual self-injurers scored higher on impulsiveness and alexithymia. The gesture\u2019s repetition seems relevant to the global clinical picture: habitual self-injurers appear more likely to seek help from the sociosanitary services. We found a difference between the self-injurers\u2019 and their parents\u2019 awareness of the disorder. Conclusion: Habitual self-injurers show signs of having difficulty with assessing the consequences of their actions (nonplanning impulsiveness) and the inability to manage their feelings. Given the significantly higher scores found for cases than for controls on all the psychopathological scales, NSSI can be seen as a cross-category psychiatric disorder, supporting the Diagnostic and Statistical Manual of Mental Disorders decision to include it as a pathological entity in its own right