Research note: Indirect evidence of avian Metapneumovirus circulation in broilers in Italy.

The clinical relevance of avian metapneumovirus (aMPV) is growing in the poultry sector, especially in broiler farming, where no vaccination is administered in Italy. Given the naïve status of the birds, a serological survey was conducted in a densely populated area of Northern Italy, to evaluate aMPV circulation. Seven farms were selected and sampled in summer/fall, then sampling was repeated in the following season (winter/spring) to assess a possible seasonal effect.

Energy penetration into arrays of aligned nanowires irradiated with relativistic intensities: Scaling to terabar pressures.

Ultrahigh-energy density (UHED) matter, characterized by energy densities >1 × 10 J cm and pressures greater than a gigabar, is encountered in the center of stars and inertial confinement fusion capsules driven by the world's largest lasers. Similar conditions can be obtained with compact, ultrahigh contrast, femtosecond lasers focused to relativistic intensities onto targets composed of aligned nanowire arrays. We report the measurement of the key physical process in determining the energy density deposited in high-aspect-ratio nanowire array plasmas: the energy penetration.

Extreme degree of ionization in homogenous micro-capillary plasma columns heated by ultrafast current pulses.

Homogeneous plasma columns with ionization levels typical of megaampere discharges are created by rapidly heating gas-filled 520-μm-diameter channels with nanosecond rise time current pulses of 40 kA. Current densities of up to 0.3  GA cm^{-2} greatly increase Joule heating with respect to conventional capillary discharge Z pinches, reaching unprecedented degrees of ionization for a high-Z plasma column heated by a current pulse of remarkably low amplitude.

X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility.

An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution ∼ 50. It has been used at the LULI-2000 laser facility at École Polytechnique (France) to measure the Δn = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required.

Miniature shock tube for laser driven shocks.

We describe in this paper the design of a miniature shock tube (smaller than 1 cm(3)) that can be placed in a vacuum vessel and allows transverse optical probing and longitudinal backside extreme ultraviolet emission spectroscopy in the 100-500 A range. Typical application is the study of laser launched radiative shocks, in the framework of what is called "laboratory astrophysics."