Confinement and scaling of the vortex vacuum of SU(2) lattice gauge theory

The magnetic vortices which arise in SU(2) lattice gauge theory in center projection are visualized for a given time slice. We establish that the number of vortices piercing a given 2-dimensional sheet is a renormalization group invariant and therefore physical quantity. We find that roughly 2 vortices pierce an area of 1 fm^2.Comment: 8 pages, LaTeX, 4 figures using eps

Measuring cognitive effort without difficulty

An important finding in the cognitive effort literature has been that sensitivity to the costs of effort varies between individuals, suggesting that some people find effort more aversive than others. It has been suggested this may explain individual differences in other aspects of cognition; in particular that greater effort sensitivity may underlie some of the symptoms of conditions such as depression and schizophrenia. In this paper, we highlight a major problem with existing measures of cognitive effort that hampers this line of research, specifically the confounding of effort and difficulty. This means that behaviour thought to reveal effort costs could equally be explained by cognitive capacity, which influences the frequency of success and thereby the chance of obtaining reward. To address this shortcoming, we introduce a new test, the Number Switching Task (NST), specially designed such that difficulty will be unaffected by the effort manipulation and can easily be standardised across participants. In a large, online sample, we show that these criteria are met successfully and reproduce classic effort discounting results with the NST. We also demonstrate the use of Bayesian modelling with this task, producing behavioural parameters which can be associated with other measures, and report a preliminary association with the Need for Cognition scale

Reflective liquid crystal hybrid beam-steerer

We report on efficient optical beam-steering using a hot-embossed reflective blazed grating in combination with liquid crystal. A numerical simulation of the electrical switching characteristics of the liquid crystal is performed and the results are used in an FDTD optical simulator to analyze the beam deflection. The corresponding experiment on the realized device is performed and is found to be in good agreement. Beam deflection angles of 4.4° upon perpendicular incidence are found with low applied voltages of 3.4V. By tilting the device with respect to the incoming optical beam it can be electronically switched such that the beam undergoes either total internal reflection or reflection with a tunable angle

Análisis teórico-práctico de la cultura organizacional = Theoretical and practical analysis of organizational culture

El marco teórico del trabajo ilustra, en primera instancia, una amplia visión sobre el concepto de cultura organizacional, su origen, desarrollo y valor como recurso. La segunda parte trata, sobre la clasificación de los cuatro diferentes tipos que sirven de guía para cumplir distintos objetivos, buscando coherencia en su desarrollo. Por último, un análisis en profundidad de los pilares más característicos, con el que identificar las dificultades formales e informales para guiar la estrategia propuesta. La parte práctica trata de trasladar este análisis a la realidad de una empresa, plasmando, mediante la observación directa y la técnica de la entrevista, su esquema cultural. Se utiliza para ello, los preceptos del sistema propuesto. Para así señalar los puntos fuertes de la línea argumental en la práctica y las barreras al desarrollo que se crean en la organización y en dos departamento

From obstacle to opportunity: Problem-solving and competence creation in new firms

This paper aims to identify how entrepreneurial responses to ‘barriers’ can give rise to opportunities for new firms. The poor predictive record of studies analysing success attributes and favourable initial factors as determinants of new firm growth reflects the diversity of entrepreneurial responses to problems of growth, as illustrated by three case studies of new companies which were able to overcome adverse initial conditions despite the lack of early ‘success attributes’. They did so by finding alternative opportunities and by achieving resource economy, resource leverage and resource creation, aided by strategic relationships formed with other players. Spurred by the problems they encounter, entrepreneurial firms revise their business conjecture and engage in innovative activities, their business model evolving through trial and error. Creative responses to unexpected developments by entrepreneurial decision makers have implications for research methodology and business support