Left restriction semigroups have appeared at the convergence of several flows of research, including the theories of abstract semigroups, of partial mappings, of closure operations and even in logic. For instance, they model unary semigroups of partial mappings on a set, where the unary operation takes a map to the identity map on its domain. This perspective leads naturally to dual and two-sid...

The paper considers the impact of healthcare systems and how they are financed on the life expectancies (LEs) of women and men in 19 OECD countries during the period 1990-2005 using OECD Health Data 2009. There is a gap in life expectancy (LE) between men and women, with women living longer than men, and most studies point to socio-economic variables and lifestyle and health-related behaviors. ...

A bstract. We study cellular automata. with addi tive rules on finite undi rected graphs. The addition is carried out in some finite abelian mono id. We investigate the prob lem of deciding wheth er a given configuration has a predecessor . Depending on th e underlying monoid this prob lem is solvable in polynomial time or NP-complete. Furt hermo re, we st udy the global reversibility of cellul...

It is relevant to consider uncertainty in individual predictions when quantitative structure-activity (or property) relationships (QSARs) are used to support decisions of high societal concern. Successful communication of uncertainty in the integration of QSARs in chemical safety assessment under the EU Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) system can be f...

This paper examines the relationship between workforce demographics and aggregate productivity. Cross country regressions show changes in the age structure of the workforce to be significantly correlated with changes in aggregate productivity. Different demographic structures may be related to almost one quarter of the persistent productivity gap between the OECD and low income nations. The mag...

This paper revisits the relationship between health and growth in light of modern endogenous growth theory. We propose a unified framework that encompasses the growth effects of both the rate of improvement of health and the level of health. Based on cross-country regressions over the period 19602000, where we instrument for both variables, we find that a higher initial level and a higher rate ...

In this paper, we propose an algorithm for doing reconstruction of general 3D-curves from a number of 2D-images taken by uncalibrated cameras. No point correspondences between the images are assumed except for the end points. The curve and the view points are uniquely reconstructed, modulo common projective transformations. Furthermore, the algorithm is independent of the choice of coordinates,...

We propose an approach to all-optical frequency standard design, based on a counterintuitive combination of the coherent population trapping effect and signal discrimination at the maximum of absorption for the probe radiation. The short-term stability of such a standard can achieve the level of 10−14/ . The physics beyond this approach is a dark resonance splitting caused by the interaction of...

The cavability assessment of rock mass cavability and indicating the damage profile ahead of a cave-back is of great importance in the evaluation of a caving mine operation, which can influence all aspects of the mine operation. Due to the lack of access to the caved zones, our current knowledge about the damage profile in caved zones is very limited. Among the different approaches available, p...