Vector meson production and [SU(3) ⊗SU(3)]coll symmetry

The collinear production of a vector meson is considered in the scattering of pseudoscalar mesons on baryons. Relations between the experimental quantities, following from the symmetry [SU(3) SU(3)]_coll, are obtained.On leave from the Nuclear Research Institute of the Czechoslovak Academy of Sciences, e.     

Integrable model of the interaction of counter-propagating weakly nonlinear waves on the fluid boundary in a horizontal electric field

Theoretical and Mathematical Physics - We consider the nonlinear dynamics of the free surface of a high-permittivity dielectric fluid in a strong horizontal electric field. In the framework of the...     

Observation of triatomic species with conflicting aromaticity: AlSi2- and AlGe2-

We created mixed triatomic clusters, AlCGe(-), AlSi(2)(-), and AlGe(2)(-), and studied their electronic structure and chemical bonding using photoelectron spectroscopy and ab initio calculations. Excellent agreement between theoretical and experimental photoelectron spectra confirmed the predicted global minimum structures for these species. Chemical bonding analysis revealed that the AlSi(2)(-) and AlGe(2)(-) anions can be described as species with conflicting (sigma-antiaromatic and pi-aromatic) aromaticity. The AlCGe(-) anion represents an interesting example of chemical species which is between classical and aromatic.     

PAST AND FUTURE MANAGEMENT OF A COLLAPSED FISHERY: THE BAY OF BISCAY ANCHOVY

Abstract We analyze the efficiency of the international management of the Bay of Biscay anchovy. While a sharing agreement between France and Spain has been in place since 1992, the fish stock collapsed in 2005 and the fishery closed from 2005 to spring 2010. We consider differences in production technologies between both countries and calibrate our model using data from 1987 to 2009. Our results suggest two sources of rent dissipation under the existing sharing agreement: inefficient quota allocation and production inefficiencies due to inflexible national regulations. We discuss several alternatives to improve management.     

Use of the tagged neutron technique for detecting dangerous underwater substances

The tagged neutron technique (TNT) is analyzed in terms of its application for detecting dangerous substances hidden in underwater objects. The use of the technique for solving these problems is justified theoretically. The main characteristics of a prototype detector aimed at detecting explosives in a water environment are determined.     

High-reflectivity multilayer mirrors for a vacuum-ultraviolet interval of 35-50nm

Sc-Si multilayers are suggested as high-reflectivity coatings for a VUV interval of 35-50 nm. Fabricated mirrors show normal-incidence reflectivity of 30-54%, which is high enough for effective manipulation of the beams of compact-discharge, laser-driven x-ray lasers. The values obtained are not, however, limits for Sc-Si coatings. Theoretical estimations as well as electron microscopy studies of Sc-Si interfaces indicate a large potential for a further increase in their reflectivity.     

Bifurcating fragmentation behavior of gas-phase tryptic peptide dications in collisional activation

Collision-activated dissociation (CAD) of tryptic peptides is a cornerstone of mass spectrometry-based proteomics research. Principal component analysis of a database containing 15,000 high-resolution CAD mass spectra of gas-phase tryptic peptide dications revealed that they fall into two classes with a good separation between the classes. The main factor determining the class identity is the relative abundance of the peptide bond cleavage after the first two N-terminal residues. A possible scenario explaining this bifurcation involves trans- to cis-isomerization of the N-terminal peptide bond, which facilitates solvation of the N-terminal charge on the second backbone amide and formation of stable b(2) ions in the form of protonated diketopiperazines. Evidence supporting this scenario is derived from statistical analysis of the high-resolution CAD MS/MS database. It includes the observation of the strong deficit of a(3) ions and anomalous amino acid preferences for b(2) ion formation.