621 research outputs found
THE VALIDITY OF THE GENERALIZED REPRODUCTION SCHEME -In Comparison with the Theories of P. Sraffa and of M. Kalecki-
Vertex operator for the non-autonomous ultradiscrete KP equation
We propose an ultradiscrete analogue of the vertex operator in the case of
the ultradiscrete KP equation--several other ultradiscrete equations--which
maps N-soliton solutions to N+1-soliton ones.Comment: 9 page
PLA2 activity is required for nuclear shrinkage in caspase-independent cell death
Apoptosis is defined on the basis of morphological changes like nuclear fragmentation and chromatin condensation, which are dependent on caspases. Many forms of caspase-independent cell death have been reported, but the mechanisms are still poorly understood. We found that hypoxic cell death was independent of caspases and was associated with significant nuclear shrinkage. Neither Bcl-2 nor Apaf-1 deficiency prevented hypoxic nuclear shrinkage. To understand the molecular mechanism of the nuclear shrinkage, we developed an in vitro system using permeabilized cells, which allowed us to purify a novel member of the phospholipase A2 (PLA2) family that induced nuclear shrinkage. Purified PLA2 induced nuclear shrinkage in our permeabilized cell system. PLA2 inhibitors prevented hypoxic nuclear shrinkage in cells and cell death. Hypoxia caused elevation of PLA2 activity and translocation of intracellular PLA2s to the nucleus. Knockdown of the Ca2+-independent PLA2 delayed nuclear shrinkage and cell death. These results indicate that Ca2+-independent PLA2 is crucial for a caspase-independent cell death signaling pathway leading to nuclear shrinkage
Symmetric Linear Backlund Transformation for Discrete BKP and DKP equation
Proper lattices for the discrete BKP and the discrete DKP equaitons are
determined. Linear B\"acklund transformation equations for the discrete BKP and
the DKP equations are constructed, which possesses the lattice symmetries and
generate auto-B\"acklund transformationsComment: 18 pages,3 figure
Bilinear Equations and B\"acklund Transformation for Generalized Ultradiscrete Soliton Solution
Ultradiscrete soliton equations and B\"acklund transformation for a
generalized soliton solution are presented. The equations include the
ultradiscrete KdV equation or the ultradiscrete Toda equation in a special
case. We also express the solution by the ultradiscrete permanent, which is
defined by ultradiscretizing the signature-free determinant, that is, the
permanent. Moreover, we discuss a relation between B\"acklund transformations
for discrete and ultradiscrete KdV equations.Comment: 11 page
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