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Evolution: functional evolution of nuclear structure.
The evolution of the nucleus, the defining feature of eukaryotic cells, was long shrouded in speculation and mystery. There is now strong evidence that nuclear pore complexes (NPCs) and nuclear membranes coevolved with the endomembrane system, and that the last eukaryotic common ancestor (LECA) had fully functional NPCs. Recent studies have identified many components of the nuclear envelope in living Opisthokonts, the eukaryotic supergroup that includes fungi and metazoan animals. These components include diverse chromatin-binding membrane proteins, and membrane proteins with adhesive lumenal domains that may have contributed to the evolution of nuclear membrane architecture. Further discoveries about the nucleoskeleton suggest that the evolution of nuclear structure was tightly coupled to genome partitioning during mitosis
On nilpotent evolution algebras
The type and several invariant subspaces related to the upper annihilating
series of finite-dimensional nilpotent evolution algebras are introduced. These
invariants can be easily computed from any natural basis. Some families of
nilpotent evolution algebras, defined in terms of a nondegenerate symmetric
bilinear form and some commuting symmetric diagonalizable endomorphisms
relative to the form, are explicitly constructed. Both the invariants and these
families are used to review and complete the classification of nilpotent
evolution algebras up to dimension five over algebraically closed fields.Comment: 19 page
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Evolution Of Galaxies .2. Chemical Evolution Coefficients
NSF GP-18355, GP-32051Astronom
Black Hole Evolution
Black hole formation and evaporation is studied in the semiclassical
approximation in simple 1+1-dimensional models, with emphasis on issues related
to Hawking's information paradox. Exact semiclassical solutions are described
and questions of boundary conditions and vacuum stability are discussed. The
validity of the semiclassical approximation has been called into question in
the context of the information puzzle. A different approach, where black hole
evolution is assumed to be unitary, is described. It requires unusual causal
properties and kinematic behavior of matter that may be realized in string
theory. Based on lectures given at the 1994 Trieste Spring SchoolComment: 30 pages, 8 figures, late
Evolution is Viral: The Theory of Collective Discontinuous Evolution
Herein will be discussed the problems associated with the origin of species according to Darwinist processes of individual mutations. We will argue that individual mutations cannot be the driving force of species origination. A far more probable explanation is a process of collective mutation that affects numerous individuals near simultaneously akin to an infectious disease. These types of mutations might be precipitated by viruses which would create a discontinuous leap into another species. Such a mechanism also sheds light on the increased rate of evolution observed currently
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