Solving parity games: Explicit vs symbolic

In this paper we provide a broad investigation of the symbolic approach for solving Parity Games. Specifically, we implement in a fresh tool, called, four symbolic algorithms to solve Parity Games and compare their performances to the corresponding explicit versions for different classes of games. By means of benchmarks, we show that for random games, even for constrained random games, explicit algorithms actually perform better than symbolic algorithms. The situation changes, however, for structured games, where symbolic algorithms seem to have the advantage. This suggests that when evaluating algorithms for parity-game solving, it would be useful to have real benchmarks and not only random benchmarks, as the common practice has been

Respiratory inhibition of isolated mammalian mitochondria by salivary antifungal peptide histatin-5

Histatin-5 is a peptide secreted in the human saliva, which possesses powerful antifungal activity. Previous studies have shown that this peptide exerts its candidacidal activity, through the inhibition of both mitochondrial respiration and the formation of reactive oxygen species. The purpose of the present study was to investigate the biological consequences of histatin-5 action on mammalian mitochondria to verify if the toxic mechanism exerted on mitochondria from Candida albicans is an exclusive for fungal cells. Moreover, hypothesising that the damage exerted on mitochondria may induce programmed cellular death pathways, we evaluated two main markers of apoptosis: the mitochondrial membrane potential (DeltaPsi) and the release of cytochrome c. The results obtained show that exposure of isolated mammalian mitochondria to histatin-5 determines: (i) a large inhibition of the respiratory chain at the level of complex 1, (ii) a slight decrease in the mitochondrial membrane potential, and (iii) no release of cytochrome c. (C) 2003 Elsevier Inc. All rights reserved

Sub-wavelength focusing of high intensities in microfibre tips

Sub-wavelength efficient intensity confinement has been demonstrated in nanostructured optical microfibre tips. Focus Ion Beam (FIB) milling was used to nanostructure gold-coated optical microfibre tips and form apertures at the apex. Simulations were carried out to optimize the device design. Enhanced transmission efficiency (higher than 10-2) was achieved in spot sizes of ~λ/10. Nanostructured microfibre tips have the potential for a number of applications including optical recording, photolithography and scanning near-field optical microscopy (SNOM)

Evidence for ideal insulating/conducting state in a 1D integrable system

Using numerical diagonalization techniques we analyze the finite temperature/frequency conductance of a one dimensional model of interacting spinless fermions. Depending on the interaction, the observed finite temperature charge stiffness and low frequency conductance indicate a fundamental difference between integrable and non-integrable cases. The integrable systems behave as ideal conductors in the metallic regime and as ideal insulators in the insulating one. The non-integrable systems are, as expected, generic conductors in the metallic regime and activated ones in the insulating regime.Comment: revtex file, followed by 5 uuencoded postscript figure

Connection between low energy effective Hamiltonians and energy level statistics

We study the level statistics of a non-integrable one dimensional interacting fermionic system characterized by the GOE distribution. We calculate numerically on a finite size system the level spacing distribution $P(s)$ and the Dyson-Mehta $\Delta_3$ correlation. We observe that its low energy spectrum follows rather the Poisson distribution, characteristic of an integrable system, consistent with the fact that the low energy excitations of this system are described by the Luttinger model. We propose this Random Matrix Theory analysis as a probe for the existence and integrability of low energy effective Hamiltonians for strongly correlated systems.Comment: REVTEX, 5 postscript figures at the end of the fil

MARKET ANALYSIS, TLARS SELECTION AND PRELIMINARY DESIGN INVESTIGATIONS FOR A REGIONAL HYBRID-ELECTRIC AIRCRAFT

This paper is framed in the context of the GENESIS Project (Gauging the ENvironmEntal Sustainability of electrIc and hybrid aircraft Systems), which complies with the European Union topic JTI-CS2-2020-CFP11-THT13 (Sustainability of Hybrid-Electric Aircraft System Architectures) as part of the Clean Sky 2 programme for Horizon 2020. The research work is focused on gauging the environmental sustainability of electric aircraft in a life-cycle-based, foresight perspective to support the development of a technology roadmap for transitioning towards sustainable and competitive electric aircraft systems. The analyzed aircraft segment is regional aircraft, to identify, design and assess prospectively the best energy storage and transmission topology. Different alternatives including batteries, fuel cells, hybrid and conventional powertrain technologies are evaluated and compared over different time horizons. In particular, the paper is focused on the description of the workflow implemented to define the Top-Level Aircraft Requirements for a non-conventional regional class hybrid-electric aircraft with 50 passengers, and on the identification of key specifications in terms of on-board energy storage, shaft power level and weight

Electronic States and Superconductivity in Multi-layer High-Tc Cuprates

We study electronic states of multilayer cuprates in the normal phases as functions of the number of CuO_2 planes and the doping rate. The resonating valence bond wave function and the Gutzwiller approximation are used for a two-dimensional multilayer t-t'-t''-J model. We calculate the electron-removal spectral functions at (\pi,0) in the CuO_2 plane next to the surface to understand the angle-resolved photoemission spectroscopy (ARPES) spectra. We find that the trilayer spectrum is narrower than the bilayer spectrum but is wider than the monolayer spectrum. In the tri- and tetralayer systems, the outer CuO_2 plane has different superconducting amplitude from the inner CuO_2 plane, while each layer in the bilayer systems has same amplitude. The recent ARPES and NMR experiments are discussed in the light of the present theory.Comment: 7 pages, 7 figure