Multiparticle Quantum Superposition and Stimulated Entanglement by Parity Selective Amplification of Entangled States

A multiparticle quantum superposition state has been generated by a novel phase-selective parametric amplifier of an entangled two-photon state. This realization is expected to open a new field of investigations on the persistence of the validity of the standard quantum theory for systems of increasing complexity, in a quasi decoherence-free environment. Because of its nonlocal structure the new system is expected to play a relevant role in the modern endeavor on quantum information and in the basic physics of entanglement.Comment: 13 pages and 3 figure

Modelling the Frequency of Interarrival Times and Rainfall Depths with the Poisson Hurwitz-Lerch Zeta Distribution

The Poisson-stopped sum of the Hurwitz-Lerch zeta distribution is proposed as a model for interarrival times and rainfall depths. Theoretical properties and characterizations are investigated in comparison with other two models implemented to perform the same task: the Hurwitz-Lerch zeta distribution and the one inflated Hurwitz-Lerch zeta distribution. Within this framework, the capability of these three distributions to fit the main statistical features of rainfall time series was tested on a dataset never previously considered in the literature and chosen in order to represent very different climates from the rainfall characteristics point of view. The results address the Hurwitz-Lerch zeta distribution as a natural framework in rainfall modelling using the additional random convolution induced by the Poisson-stopped model as a further refinement. Indeed the Poisson contribution allows more flexibility and depiction in reproducing statistical features, even in the presence of very different climates

Experimental Detection of Entanglement with Polarized Photons

We report on the first experimental realization of the entanglement witness for polarization entangled photons. It represents a recently discovered significant quantum information protocol which is based on few local measurements. The present demonstration has been applied to the so-called Werner states, a family of ''mixed'' quantum states that include both entangled and non entangled states. These states have been generated by a novel high brilliance source of entanglement which allows to continuously tune the degree of mixedness

Influence of Anodizing by Electro-Chemical Oxidation on Fatigue and Wear Resistance of the EV31A-T6 Cast Magnesium Alloy

In the last decades, several anodizing processes for Mg alloys have been proposed to achieve a good wear and corrosion resistance combination. In particular, Electro-Chemical Oxidation (ECO) showed an improved dense and compact anodized layer compared to other anodizing processes carried out above the dielectric breakdown voltage, such as Plasma Electrolytic Oxidation (PEO). However, the influence of the ECO treatment on the tribological behavior and cyclic mechanical performance of Mg alloys has not been investigated yet. This paper reports on the influence of ECO on dry sliding behavior (vs. 100Cr6 bearing steel (block-on-ring contact geometry)) and rotating bending fatigue performance of the rare earth (RE)-containing Mg alloy EV31A-T6, comparing it with both untreated EV31A-T6 and PEO-treated EV31A-T6, used as benchmarks. The ECO-treated alloy showed improved tribological behavior (critical load for coating failure one order of magnitude higher and coefficient of friction 40% lower than for PEO) and fatigue strength (no decrease for ECO-treated samples compared to the untreated alloy, while PEO-treated samples induced a 15% decrease) due to the increased compactness and lower defectivity of the anodized layer, induced by the minimization of destructive arc discharges during coating growth. In addition, the ECO treatment significantly improved wear resistance compared to the untreated alloy, avoiding, at the same time, the decrease in fatigue strength, which typically occurs after PEO. Therefore, the ECO process can be applied to improve wear resistance without decreasing the fatigue strength of high-performance components

High energy parton-parton amplitudes from lattice QCD and the stochastic vacuum model

Making use of the gluon gauge-invariant two-point correlation function, recently determined by numerical simulation on the lattice in the quenched approximation and the stochastic vacuum model, we calculate the elementary (parton-parton) amplitudes in both impact-parameter and momentum transfer spaces. The results are compared with those obtained from the Kr\"{a}mer and Dosch ansatz for the correlators. Our main conclusion is that the divergences in the correlations functions suggested by the lattice calculations do not affect substantially the elementary amplitudes. Phenomenological and semiempirical information presently available on elementary amplitudes is also referred to and is critically discussed in connection with some theoretical issues.Comment: Text with 11 pages in LaTeX (twocolumn form), 10 figures in PostScript (psfig.tex used). Replaced with changes, Fig.1 modified, two references added, some points clarified, various typos corrected. Version to appear in Phys. Rev.

Investigation on Opisthorchis felineus occurrence and life cycle in Italy

Opisthorchiasis is a fish borne parasitic infection caused by helminths of the genus Opisthorchis (Digenea, Opisthorchiidae), affecting humans and other fish-eating mammals. Despite Opisthorchis felineus was first described in Italy in 1884, no cases of human opisthorchiasis were reported in this country until 2004; from then on, 4 outbreaks due to this species have been recorded in Central Italy. Following the more relevant of these outbreaks, involving 34 people in August 2007, snails, fishes and fecal samples collected from the Bolsena and Bracciano lakes (Central Italy) were analyzed in order to define the cycle of O. felineus in the area and investigate its prevalence in the different hosts. Pools of 20–40 snails each (4983 specimens altogether) of the genus Bithynia were analyzed by PCR for parasite DNA detection. Eight hundred and ninety-four fish belonging to 12 species were collected from the two lakes and tested for metacercariae both by muscle compression and digestion techniques. Eighty-seven fecal samples of 5 putative definitive host species were collected very close to the two lakes and tested for parasite eggs detection by formalin–ethyl acetate concentration technique. Identification at the species level of metacercariae and eggs, respectively, from fish and stool was confirmed by PCR analysis and sequencing. O. felineus DNA was detected in 0.08% (overall minimum infection rate) of snails of the genus Bithynia from the two lakes. The tench, Tinca tinca, was the only fish found infested in both lakes (prevalence 88.5%). O. felineus eggs were found only in cat feces (prevalence 46.4%). The tench represents the only threat for the human consumption in the study area while Coregonus sp., the most economically important species for the local fishery and frequently consumed raw marinated, resulted to be not infected. The high prevalence recorded both in fish and in definitive host suggests a widespread and massive presence of the parasite in the area. Further studies are needed to better investigate the possible role of some cyprinids species as intermediate hosts, in order to check their safety for human consumption

Measurement of the neutron detection efficiency of a 80% absorber - 20% scintillating fibers calorimeter

The neutron detection efficiency of a sampling calorimeter made of 1 mm diameter scintillating fibers embedded in a lead/bismuth structure has been measured at the neutron beam of the The Svedberg Laboratory at Uppsala. A significant enhancement of the detection efficiency with respect to a bulk organic scintillator detector with the same thickness is observed.Comment: 10 pages, 7 figure

Measurement of neutron detection efficiency between 22 and 174 MeV using two different kinds of Pb-scintillating fiber sampling calorimeters

We exposed a prototype of the lead-scintillating fiber KLOE calorimeter to neutron beam of 21, 46 and 174 MeV at The Svedberg Laboratory, Uppsala, to study its neutron detection efficiency. This has been found larger than what expected considering the scintillator thickness of the prototype. %To check our method, we measured also the neutron %detection efficiency of a 5 cm thick NE110 scintillator. We show preliminary measurement carried out with a different prototype with a larger lead/fiber ratio, which proves the relevance of passive material to neutron detection efficiency in this kind of calorimeters