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Quantum statistics of a forced harmonic oscillator acted upon by a time-dependent external force are derived using the Wilcox trick and the time-dependent inhomogeneous Bogoliubov transformation formalism. The internal energy, fluctuation of the particle-number average and entropy of this nonequilibrium system are presented explicitly.

The cellular prion protein (PrP(C)) is a highly conserved protein among mammals and is considered to have important cellular functions. Despite decades of intensive research, however, the physiological function of PrP(C) remains unclear. Sho (Shadoo, shadow of prion protein) and PrP(C) have similar N-terminals, which suggests that the two proteins share biological functions. Using truncation mutants of both proteins and yeast two-hybrid analysis, with validation by co-immunoprecipitation and surface plasmon resonance (SPR), we have identified an interaction between Sho 61-77 and PrP(C) 108-126 domains. This indicates that Sho may play a role in the physiological function of PrP(C) and prion pathogenesis.

Surface plasmon resonance was used to develop a rapid, label-free and sensitive immunoassay for detection of Prion protein (PrP). Anti-PrP monoclonal antibodies immobilized on the biosensor surface were allowed to bind various concentrations of cellular prion protein (PrP(C)), followed by a pulse with additional soluble anti-PrP polyclonal antibodies to intensify the signal. The interaction of antibody with antigen was monitored in real time. With this method, it was possible to detect PrP(C) with a limit of 31.7 ng/ml in serum and 13.1 ng/ml in HEPES-saline, requiring 1 h for a single sample measurement. The assay also detected misfolded prion protein (PrP(Sc)) in spiked serum and PrP(Sc) in scrapie-infected mouse brains. This is a rapid and sensitive assay for the detection of PrP in serum that could be developed into a platform for a serum-based TSE test.

N-atom single-mode radiation field interaction system is regarded as an interacting quasi-boson-photon system and is treated as a grand canonical ensemble.The explicit expression for the thermodynamical potential of the system is obtained using cluster expansion method.Some thermodynamic quantities are derived in terms of the general thermodynamic formulas.The numerical calculation and diagrams exhibit the thermodynamic behavior of the system.The singularities appearing in the critical line and other places furnish evidences of existence of the second kind of phase transformation in this collective system.

The closed expressions with a parameter of the Bogoliubov unitary transformation are derived. The reduced Hamiltonian of the quantum Bose fluid is diagonalized in the original particle number representation. The manifestation of nonclassical character in the two mode radiation is extended to the quantum Bose fluid. Finally, the eigenstates of the Hamiltonian are established to be the squeezed boson pair number states with a nonclassical character.