Pion Tensor Generalized Parton Distributions in a Covariant Constituent Quark Model

The pion tensor generalized parton distributions are evaluated within a covariant, analytic constituent quark model. The generalized form factors for the first two Mellin moments and the probability densities of polarized quarks in the impact parameter space are derived and compared with lattice QCD and quark model results.     

PRESS-MAG-O: A new facility to probe materials and phenomena under extreme conditions

In the recent years, several experiments performed under high magnetic fields (HMFs), at high pressure (HP) and/or at low temperature (LT) have led to spectacular discoveries in condensed matter. In many new systems, although challenging, it is strategic to perform a magneto-optical analysis, to investigate the phonon behavior in the far infrared (IR) domain. By combining HMF and HP in a wide temperature (T) range to perform concurrently IR magneto-optics and ac-magneto-dynamic experiments, it will be possible to achieve unique information on systems and/or new phenomena, almost impossible to obtain with standard spectroscopic methods. Here we present PRESS-MAG-O, a new facility under construction that will perform HP experiments under HMF in a wide T range. The system is expected to be operational by the end of 2008 and will be tested at SINBAD, the IR synchrotron radiation beamline operational since 2001 at DAΦNE (Double Annular Φ-factory for Nice Experiments), the storage ring of the INFN Frascati National Laboratory (LNF). While for IR experiments an interferometer will be used, for the magneto-dynamic experiments a SQUID magnetometer in the 10 Hz-2 KHz frequency range will be utilized. HP will be applied to samples by a Cu-Be diamond anvil cell (DAC), so that the device will be able to collect FTIR spectra and high harmonic ac susceptibility data in a dc magnetic field up to 8 T and to about 20 GPa in a wide temperature range (4.2-200 K).     

Modeling wave-induced pore pressure and effective stress in a granular seabed

The response of a sandy seabed under wave loading is investigated on the basis of numerical modeling using a multi-scale approach. To that aim, the discrete element method is coupled to a finite volume method specially enhanced to describe compressible fluid flow. Both solid and fluid phase mechanics are upscaled from considerations established at the pore level. Model’s predictions are validated against poroelasticity theory and discussed in comparison with experiments where a sediment analog is subjected to wave action in a flume. Special emphasis is put on the mechanisms leading the seabed to liquefy under wave-induced pressure variation on its surface. Liquefaction is observed in both dilative and compactive regimes. It is shown that the instability can be triggered for a well-identified range of hydraulic conditions. Particularly, the results confirm that the gas content, together with the permeability of the medium are key parameters affecting the transmission of pressure inside the soil.     

Connecting measures by means of branched transportation networks at finite cost

  We study the couples finite Borel measures φ ₀ and φ ₁ with compact support in which can be transported to each other at a finite W ^α cost, where

E-Nose Discrimination of Abnormal Fermentations in Spanish-Style Green Olives

Current legislation in Spain indicates that table olives must be free of off-odors and off-flavors and without symptoms of ongoing alteration or abnormal fermentations. In this regard, the International Olive Council (IOC) has developed a protocol for the sensory classification of table olives according to the intensity of the predominantly perceived defect (PPD). An electronic nose (e-nose) was used to assess the abnormal fermentation defects of Spanish-style table olives that were previously classified by a tasting panel according to the IOC protocol, namely zapateria, butyric, putrid, and musty or humidity. When olives with different defects were mixed, the putrid defect had the greatest sensory impact on the others, while the butyric defect had the least sensory dominance. A total of 49 volatile compounds were identified by gas chromatography, and each defect was characterized by a specific profile. The e-nose data were analyzed using principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA). The different defects were clearly separated from each other and from the control treatment, independently of PPD intensity. Moreover, the e-nose differentiated control olives from table olives with combined sensory defects despite the dilution effect resulting from the combination. These results demonstrate that e-nose can be used as an olfactory sensor for the organoleptic classification of table olives and can successfully support the tasting panel.     

Immediate structural changes of porcine renal arteries after angioplasty: a histological and morphometric study

The aim of this research was to characterize the immediate alterations induced by angioplasty and to compare the results of the application of two types of balloons. Ten porcine renal arteries were dilated with a compliant balloon, and ten with a non-compliant balloon. After angioplastic treatment arterial specimens were wax embedded for light microscopy. Sections were stained with the orcein-Van Gieson method, orcein, haematoxylin-eosin, and PAS. Image analysis was performed taking into consideration the following parameters: thickness of the entire wall, of the tunica media and of the inner elastic lamina. The major axes of the smooth muscle cells nuclei were also measured. The effects of the two types of balloon resulted in changes consisting in thinning of the entire arterial wall, reduction of the tunica media, distension of reticular fibers, presence of wide spaces between smooth muscle cells, stretching of smooth muscle cells, inner elastic lamina thickening. Both angioplasty devices used can modify the vascular wall. The identification of the tunica media structural damages might be useful in order to estimate the behavior of the vascular wall in the follow-up after angioplasty, because the entity of modifications could be predictive of restenosis that often takes place weeks or months after angioplasty.     

High-energy collision of two black holes

We study the head-on collision of two highly boosted equal mass, nonrotating black holes. We determine the waveforms, radiated energies, and mode excitation in the center of mass frame for a variety of boosts. For the first time we are able to compare analytic calculations, black-hole perturbation theory, and strong field, nonlinear numerical calculations for this problem. Extrapolation of our results, which include velocities of up to 0.94c, indicate that in the ultrarelativistic regime about 14+/-3% of the energy is converted into gravitational waves. This gives rise to a luminosity of order 10_(-2)c_(5)/G, the largest known so far in a black-hole merger.     

Finite groups with real conjugacy classes of prime size

We determine the structure of a finite group G whose noncentral real conjugacy classes have prime size. In particular, we show that G is solvable and that the set of the sizes of its real classes is one of the following: {1}, {1, 2}, {1, p}, or {1, 2, p}, where p is an odd prime.