Charm and bottom production in inclusive double Pomeron exchange in heavy ion collisions at the LHC

The inclusive double Pomeron exchange cross section for heavy quark pair production is calculated for nucleus-nucleus collisions at the LHC. The present estimate is based on hard diffractive factorization, corrected by absorptive corrections and nuclear effects. The theoretical uncertainties for nuclear collisions are investigated and a comparison to other approaches is presented. The production channels producing a similar final state configuration are discussed as well.Comment: 7 pages, 3 tables. Final version to be published in Physical Review

On the renormalization of the electroweak chiral Lagrangian with a Higgs

We consider the scalar sector of the effective non-linear electroweak Lagrangian with a light "Higgs" particle, up to four derivatives in the chiral expansion. The complete off-shell renormalization procedure is implemented, including one loop corrections stemming from the leading two-derivative terms, for finite Higgs mass. This determines the complete set of independent chiral invariant scalar counterterms required for consistency; these include bosonic operators often disregarded. Furthermore, new counterterms involving the Higgs particle which are apparently chiral non-invariant are identified in the perturbative analysis. A novel general parametrization of the pseudoescalar field redefinitions is proposed, which reduces to the various usual ones for specific values of its parameter; the non-local field redefinitions reabsorbing all chiral non-invariant counterterms are then explicitly determined. The physical results translate into renormalization group equations which may be useful when comparing future Higgs data at different energies

INJECTABLE HYBRID SYSTEM FOR STRONTIUM LOCAL DELIVERY TO PROMOTE BONE REGENERATION

In bone tissue regeneration strategies, injectable bone substitutes are very attractive since they can be applied with minimally invasive surgical procedures and can perfectly fill irregular defects created in cases of trauma, infection or tumor resection. These materials must combine adequate mechanical properties with the ability to induce new bone formation. Incorporating strontium (Sr) in bone substitute biomaterials may be a strategy to achieve high Sr concentrations, not in a systemic but in a local environment, taking advantage of the osteoanabolic and anti-osteoclastic activity of Sr, for the enhancement of new bone formation. In this context, the aim of the present work was to evaluate the response of a Sr-hybrid injectable system for bone regeneration, designed by our group, consisting of hydroxyapatite microspheres doped with Sr and an alginate vehicle crosslinked in situ with Sr, in an in vivo scenario. Two different animal models were used, rat (Wistar) and sheep (Merino Branco) critical sized bone defect. Non Sr-doped similar materials (Ca-hybrid) or empty defects were used as control. Sr-hybrid system led to an increased bone formation in both center and periphery of a rat critical sized defect compared to a non Sr–doped similar system, where new bone formation was restricted to the periphery. Moreover newly formed bone was identified as early as one week after its implantation in a sheep model. After eight weeks, the bone surrounded the microspheres, both in the periphery and in the center of the defect. Most importantly, the hybrid system provided a scaffold for cell migration and tissue ingrowth and offered structural support, as observed in both models. The effective improvement of local bone formation suggests that this might be a promising approach for bone regeneration, especially in osteoporotic conditions

Teaching robot modelling and control with RobLib

The paper presents a program for robotics education that runs on standard PC's under the Microsoft Windows environment. The RobLib package is designed for undergraduate students and emphasis the fundamental aspects of robot modelling and control. The software is self-explanatory and uses menus, dialog boxes with figures and context-dependent on-line help. In this perpective, students are motivated to investigate on the workspace, kinematics, dynamics, trajectory planning, position and force control of manipulators. Based on this first experience, further studies on robotics, using more sophisticated packages and concepts, are, then, more attractive from the students point of view.N/

Fractional-order position/force control of two cooperating manipulators

In this paper it is studied the implementation of fractional-order algorithms in the position/force control of two cooperating robotic manipulators. The system performance is analyzed in terms of time and frequency response for different operating condicitons.N/

Fractional-order hybrid control of robots manipulators

This paper presents the implementation of fractional-order algorithms in the position/force hybrid control of robotic manipulators. the system performance and robustness is analyzed in the time and frequency domains. The effect of dynamic backlash and flexibility is also investigated.N/

Bibliografía usada en la formación matemática del profesorado de infantil

Para realizar el estudio se escogió una muestra de 13 universidades españolas en las que se imparte la titulación y cuyas guías docentes son accesibles desde sus páginas webs. Se descargaron todas las guías docentes y se pasó la información a una base de datos ad hoc. Se realizó un proceso de estandarización de los nombres y de las referencias porque para cada asignatura utilizan formatos distintos incluso en la misma universidad. Se obtuvieron 493 referencias, que se presentan como bibliografía básica, específica, recomendada o complementaria. Posteriormente se hicieron conteos de frecuencias de cada autor, referencia y año para determinar la antigüedad de las mismas