On the Critical Behaviour of Heat Conducting Sphere out of Hydrostatic Equilibrium

We comment further on the behaviour of a heat conducting fluid when a characteristic parameter of the system approaches a critical value.Comment: 4 pages, emTex (LaTex 2.09), submitted to Classical and Quantum Gravity (Comments and Addenda

Breakdown of the linear approximation in the perturbative analysis of heat conduction in relativistic systems

We analyze the effects of thermal conduction in a relativistic fluid just after its departure from spherical symmetry, on a time scale of the order of relaxation time. Using first order perturbation theory, it is shown that, as in spherical systems, at a critical point the effective inertial mass density of a fluid element vanishes and becomes negative beyond that point. The impact of this effect on the reliability of causality conditions is discussed.Comment: 11 pages (Latex2.09) To appear in Physics Letters

Using network science to analyze football passing networks: dynamics, space, time and the multilayer nature of the game

From the diversity of applications of Network Science, in this Opinion Paper we are concerned about its potential to analyze one of the most extended group sports: Football (soccer in U.S. terminology). As we will see, Network Science allows addressing different aspects of the team organization and performance not captured by classical analyses based on the performance of individual players. The reason behind relies on the complex nature of the game, which, paraphrasing the foundational paradigm of complexity sciences "can not be analyzed by looking at its components (i.e., players) individually but, on the contrary, considering the system as a whole" or, in the classical words of after-match interviews "it's not just me, it's the team".Comment: 7 pages, 1 figur

Thermal Conduction in Systems out of Hydrostatic Equilibrium

We analyse the effects of thermal conduction in a relativistic fluid, just after its departure from hydrostatic equilibrium, on a time scale of the order of thermal relaxation time. It is obtained that the resulting evolution will critically depend on a parameter defined in terms of thermodynamic variables, which is constrained by causality requirements.Comment: 16 pages, emTex (LaTex 2.09). To appear in Classical and Quantum Gravit

Dissipative fluids out of hydrostatic equilibrium

In the context of the M\"{u}ller-Israel-Stewart second order phenomenological theory for dissipative fluids, we analyze the effects of thermal conduction and viscosity in a relativistic fluid, just after its departure from hydrostatic equilibrium, on a time scale of the order of relaxation times. Stability and causality conditions are contrasted with conditions for which the ''effective inertial mass'' vanishes.Comment: 21 pages, 1 postscript figure (LaTex 2.09 and epsfig.sty required) Submitted to Classical and Quantum Gravit

Complicaciones en el uso de aloinjertos intercalares tras resección de tumores óseos

La reconstrucción ósea mediante aloinjertos intercalares es una técnica de uso frecuente tras resecciones tumorales, que presenta -a largo plazo- mejores resultados que las endoprótesis diafisarias o los autoinjertos vascularizados. Sin embargo, entre las complicaciones más frecuentes destacan las infecciones y las fracturas del aloinjero asociadas a roturas o aflojamientos de la osteosíntesis. Se presentan dos casos tratados con reconstrucciones de este tipo en los que el sistema de osteosíntesis utilizado fracasó, en uno de ellos de forma repetida.The reconstruction of skeletal defects using bone allografts is a frequent procedure after tumoral resections associated to good long-term results, usually better than diaphyseal endoprostheses or autologous grafts. Nevertheless, there are some complications: infection and allograft fracture associated with failure or broken fixation. We report two cases of bone reconstruction in who the fixation failed, twice in one of them

Influencia biomecánica de la artroplastia total de rodilla en el apoyo metatarsal

Las articulaciones de la extremidad inferior forman una cadena cinemática y tanto desde el punto de vista normal como patológico se influyen mutuamente. El objetivo de nuestro trabajo es analizar las características del apoyo plantar en 100 pacientes subsidiarios de prótesis total de rodilla que presentan trastornos en la alineación del miembro antes y después de la corrección del eje de la extremidad que supone la cirugía. Además se compara el patrón de apoyo metatarsal con sujetos sanos de características antropométricas similares (grupo control).El genu varo preoperatorio se relaciona con un hiperapoyo de la paleta externa y un hipoapoyo de las paletas central e interna del antepié. En cambio el valgo fisiológico conseguido en el postoperatorio se corresponde con un patrón de apoyo metatarsal al año y a los dos años similar al del grupo control con pequeñas variaciones.Peer Reviewe