Flavour changing strong interaction effects on top quark physics at the LHC

We perform a model independent analysis of the flavour changing strong interaction vertices relevant to the LHC. In particular, the contribution of dimension six operators to single top production in various production processes is discussed, together with possible hints for identifying signals and setting bounds on physics beyond the standard model.Comment: Authors corrections (references added

A Flexible Implementation of a Matrix Laurent Series-Based 16-Point Fast Fourier and Hartley Transforms

This paper describes a flexible architecture for implementing a new fast computation of the discrete Fourier and Hartley transforms, which is based on a matrix Laurent series. The device calculates the transforms based on a single bit selection operator. The hardware structure and synthesis are presented, which handled a 16-point fast transform in 65 nsec, with a Xilinx SPARTAN 3E device.Comment: 4 pages, 4 figures. IEEE VI Southern Programmable Logic Conference 201

On geometry-dependent vortex stability and topological spin excitations on curved surfaces with cylindrical symmetry

We study the Heisenberg Model on cylindrically symmetric curved surfaces. Two kinds of excitations are considered. The first is given by the isotropic regime, yielding the sine-Gordon equation and $\pi$-solitons are predicted. The second one is given by the XY model, leading to a vortex turning around the surface. Helical states are also considered, however, topological arguments can not be used to ensure its stability. The energy and the anisotropy parameter which stabilizes the vortex state are explicitly calculated for two surfaces: catenoid and hyperboloid. The results show that the anisotropy and the vortex energy depends on the underlying geometry.Comment: 10 pages, 2 figures, Accepted for publication in Phys. Lett A (2013

Inhibition of S. epidermidis adhesion to hydrogel contact lenses by anionic and nonionic surfactants

In this study the adhesion of S. epidermidis to the 4 FDA groups of hydrogel CL uncoated and coated with ½ CMC of an anionic (sodium cholate) and a non-ionic surfactant (octylglucoside) was assessed. The results revealed that cell adhesion to CL was highly dependent on surface hydrophobicity. Concerning the effect of surfactants, the non-ionic one was more effective in inhibiting microbial adhesion than the ionic surfactant. Octylglucoside promoted an inhibition in the extent of bacterial adhesion of about 62%, while sodium cholate caused a decrease in the number of cells adhered of about 43%. The effect of a commercial multipurpose care solution containing 1% of poloxamine was compared and the results indicate that adhesion inhibition was greater when 0.33% of octylglucoside was used. Octylglucoside is a natural surfactant, non-toxic, harmless to the eye, and due to its high efficiency in inhibiting microbial adhesion, as proved in this work, is recommended to be incorporated in CL care solutions

Strategic perspective of error management the role of leadership and an error management culture: A mediation model

Purpose – Errors are inevitable, resulting from the human condition itself, system failures and the interaction of both. It is essential to know how to deal with their occurrence, managing them. However, the negative tone associated with them makes it difficult for most organizations to talk about mistakes clearly and transparently, for fear of being harmed, preventing their detection, treatment and recovery. Consequently, errors are not managed, remaining accumulated in the system, turning into successive failures. Organizations need to recognize the inevitability of errors, making the system robust, through leadership and an organizational culture of error management. This study aims to understand the role of these influencing variables in an error management approach. Design/methodology/approach – In this paper methodology of a quantitative nature based on a questionnaire survey that analyses error management, leadership and the organizational culture of error management of 380 workers in Portuguese companies. Findings – The results demonstrate that leadership directly influences error management and indirectly through the organizational culture of error management, giving this last variable a mediating role. Originality/value – The study covers companies from different sectors of activity on a topic that is little explored in Portugal, but part of the daily life of organizations, which should deserve greater attention from directors and managers, as they assume a privileged position to promote and develop error management mechanisms. Error management must be the daily work of leaders. This study contributes to theoretical knowledge and business practice on error management.info:eu-repo/semantics/publishedVersio

Entanglement and Bell's inequality violation above room temperature in metal carboxylates

In the present work we show that a special family of materials, the metal carboxylates, may have entangled states up to very high temperatures. From magnetic susceptibility measurements, we have estimated the critical temperature below which entanglement exists in the cooper carboxylate \{Cu$_2$(O$_2$CH)$_4$\}\{Cu(O$_2$CH)$_2$(2-methylpyridine)$_2$\}, and we have found this to be above room temperature ($T_e \sim 630$ K). Furthermore, the results show that the system remains maximally entangled until close to $\sim 100$ K and the Bell's inequality is violated up to nearly room temperature ($\sim 290$ K)