Intrinsic decoherence and classical-quantum correspondence in two coupled delta-kicked rotors

We show that classical-quantum correspondence of center of mass motion in two coupled delta-kicked rotors can be obtained from intrinsic decoherence of the system itself which occurs due to the entanglement of the center of mass motion to the internal degree of freedom without coupling to external environment

A Basic Framework for the Cryptanalysis of Digital Chaos-Based Cryptography

Chaotic cryptography is based on the properties of chaos as source of entropy. Many different schemes have been proposed to take advantage of those properties and to design new strategies to encrypt information. However, the right and efficient use of chaos in the context of cryptography requires a thorough knowledge about the dynamics of the selected chaotic system. Indeed, if the final encryption system reveals enough information about the underlying chaotic system it could be possible for a cryptanalyst to get the key, part of the key or some information somehow equivalent to the key just analyzing those dynamical properties leaked by the cryptosystem. This paper shows what those dynamical properties are and how a cryptanalyst can use them to prove the inadequacy of an encryption system for the secure exchange of information. This study is performed through the introduction of a series of mathematical tools which should be the basic framework of cryptanalysis in the context of digital chaos-based cryptography.Comment: 6 pages, 5 figure

Interaction of alpha 2-HS-glycoprotein with immobilized triazine dyes

We studied the interaction of \u3b12-HS-glycoprotein with immobilized Cibacron blue F3-GA (Blue A) and Procion red HE-3B (Red A). When whole plasma was applied on the Blue A, \u3b12-HS-glycoprotein remained unbound, together with other plasma proteins. In contrast, when this fraction was applied on the Red A, \u3b12-HS-glycoprotein was shown to bind tightly and was eluted with a linear sodium chloride gradient between 0.5 and 0.8 M. This proved to be a useful two-step technique for the purification of \u3b12-HS-glycoprotein. Further characterization revealed that the protein appeared homogeneous by immunoelectrophoresis and SDS-polyacrylamide gel electrophoresis with yields greater than 30%. A small (< 5%) but significant fraction of \u3b12-HS-glycorprotein with a same molecular weight as the native protein was consistently found in the wash of the Red A column, and may correspond to \u3b12-HS-glycoprotein bound to a yet unidentified ligand