Finite dimensional integrable Hamiltonian systems associated with DSI equation by Bargmann constraints

The Davey-Stewartson I equation is a typical integrable equation in 2+1 dimensions. Its Lax system being essentially in 1+1 dimensional form has been found through nonlinearization from 2+1 dimensions to 1+1 dimensions. In the present paper, this essentially 1+1 dimensional Lax system is further nonlinearized into 1+0 dimensional Hamiltonian systems by taking the Bargmann constraints. It is shown that the resulting 1+0 dimensional Hamiltonian systems are completely integrable in Liouville sense by finding a full set of integrals of motion and proving their functional independence.Comment: 10 pages, in LaTeX, to be published in J. Phys. Soc. Jpn. 70 (2001

The brezis-ekeland-nayroles minimization principle with mixed finite element method for elastoplastic dynamic problems

We propose a modification of the Hamiltonian formalism which can be used for dissipative systems, the Brezis-Ekeland-Nayroles principle. The formalism is specialized to the standard plasticity in small strains and dynamics. We apply it to solve the classical problem of a thin tube in plane strain subjected to an internal pressure. The continuum is discretized with mixed finite elements

Testing of disease-resistance of pokeweed antiviral protein gene (PacPAP) in transgenic cucumber (Cucumis sativus)

Transformation of pokeweed antiviral protein gene (PAP) into plants was shown to improve plant resistance to several viruses or fungi pathogens with no much negative effect on plant growth. The non-virulent defective PAP inhibits only the virus but does not interfere with the host. A non-virulent defective PAP gene (PacPAP) from Phytolacca acinosa was introduced into cucumber successfully by agrobacterium mediated method. Southern blotting and northern blotting analyses indicated that, 5 stable transgenic cucumber lines with PacPAP were obtained and PacPAP showed different expression levels in transgenic plants. The identification of resistances to disease was performed by artificial inoculation of cucumber mosaic virus (CMV) and Fusarium oxysporum fsp. cucumerinum on T0 and T1 transgenic plants. Compared with the non-transgenic susceptible plants, all transgenic plants with PacPAP showed resistance in different degree to CMV and the CMV-resistance of progeny (T1) from transgenic lines could inherit stably, but the transgenic plants did not resist to Fusarium wilt of cucumber, the PacPAP was not resistant to Fusarium oxysporum fsp. cucumerinum. This work provides a new virus resistant cucumber breeding resource.Key Words: Pokeweed antiviral protein gene, genetic transformation, Cucumis sativu