New research opportunities for roadside safety barriers improvement

Among the major topics regarding the protection of roads, restraint systems still represent a big opportunity in order to increase safety performances. When accidents happen, in fact, the infrastructure can substantially contribute to the reduction of consequences if its marginal spaces are well designed and/or effective restraint systems are installed there. Nevertheless, basic concepts and technology of road safety barriers have not significantly changed for the last two decades. The paper proposes a new approach to the study aimed to define possible enhancements of restraint safety systems performances, by using new materials and defining innovative design principles. In particular, roadside systems can be developed with regard to vehicle-barrier interaction, vehicle-oriented design (included low-mass and extremely low-mass vehicles), traffic suitability, user protection, working width reduction. In addition, thanks to sensors embedded into the barriers, it is also expected to deal with new challenges related to the guidance of automatic vehicles and I2V communication

3D Laparoscopy. A potential cutting edge in minimal invasive digestive surgery

Laparoscopic surgery has changed surgical landscape, providing reduced surgical trauma, shorter hospital stays, less postoperative pain and better outcomes than open surgery. Since its first development in the 90’s, 3D technology applied to laparoscopic surgery has had several technical improvements and now it represents, together with high definition technology, the best option in minimal invasive digestive surgery, providing shorter operative times and lower blood loss, making easier to perform surgical tasks both for trainees than for skilled surgeons. It remains a little bit more expensive than standard 2D laparoscopic devices but even cheaper than robotic equipment

The impacts of climate change on the Galapagos islands: assessing vulnerability and planning for adaptation

Historic data on thermal anomalies and El Niño events in the Eastern Tropical Pacific provide compelling evidence that Galapagos ecosystems have been exposed to rapid and abrupt oceanic and climatic changes in the past. However, their ability to adapt, if such changes become more frequent and persistent, is uncertain. This vulnerability to climate change is exacerbated by growing human pressures, driven by rapid economic growth, unregulated development, and immigration. These bring increasing numbers of cargo vessels, passenger boats and tourist flights, and invasive species. Over-fishing and rapid land-use change add to concern over loss of ecosystem integrit

Antiferromagnetic Ising model in an imaginary magnetic field

We study the two-dimensional antiferromagnetic Ising model with a purely imaginary magnetic field, which can be thought of as a toy model for the usual $\theta$ physics. Our motivation is to have a benchmark calculation in a system which suffers from a strong sign problem, so that our results can be used to test Monte Carlo methods developed to tackle such problems. We analyze here this model by means of analytical techniques, computing exactly the first eight cumulants of the expansion of the effective Hamiltonian in powers of the inverse temperature, and calculating physical observables for a large number of degrees of freedom with the help of standard multi-precision algorithms. We report accurate results for the free energy density, internal energy, standard and staggered magnetization, and the position and nature of the critical line, which confirm the mean-field qualitative picture, and which should be quantitatively reliable, at least in the high-temperature regime, including the entire critical line

Continuous Chiral Transition in Strongly Coupled Compact QED with the Standard Torus Topology

We analyze the phase diagram of compact QED on the torus with a chirally symmetric four fermion interaction added to the usual Wilson action. Inside a mean field approximation for the four fermion term, a line of first order phase transitions and another one of second order are found in the $(\beta, G)$ plane. Approaching the second order line a continuum limit can be defined. Critical exponents vary along this line in a similar way as in the non-compact model, suggesting that a non trivial interacting continuum theory can be constructed.Comment: 11 pages, latex, 1 figur

Frustration in Lattice Gauge Theory

We introduce a U(1) lattice gauge theory which incorporates explicit frustration in $d>2$. We show, by identifying an appropiate order parameter and through computer simulations, the existence of a frustrated region in the phase diagram of the model. We study this phase diagram and the nature of the transition lines.Comment: 3 pages, Latex, 5 figures, espcrc2.sty needed, Talk presented by E. Follana at LATTICE 9

Critical behaviour of the O(3) nonlinear sigma model with topological term at theta=pi from numerical simulations

We investigate the critical behaviour at theta=pi of the two-dimensional O(3) nonlinear sigma model with topological term on the lattice. Our method is based on numerical simulations at imaginary values of theta, and on scaling transformations that allow a controlled analytic continuation to real values of theta. Our results are compatible with a second order phase transition, with the critical exponent of the SU(2)_1 Wess-Zumino-Novikov-Witten model, for sufficiently small values of the coupling.Comment: Revised version. 24 pages, 7 figure