217 research outputs found
Global transposable characteristics in the yeast complete DNA sequence
Global transposable characteristics in the complete DNA sequence of the
Saccharomyces cevevisiae yeast is determined by using the metric representation
and recurrence plot methods. In the form of the correlation distance of
nucleotide strings, 16 chromosome sequences of the yeast, which are divided
into 5 groups, display 4 kinds of the fundamental transposable characteristics:
a short period increasing, a long quasi-period increasing, a long major value
and hardly relevant.Comment: 19 pages, 5 figures, 5 table
Periodic correlation structures in bacterial and archaeal complete genomes
The periodic transference of nucleotide strings in bacterial and archaeal
complete genomes is investigated by using the metric representation and the
recurrence plot method. The generated periodic correlation structures exhibit
four kinds of fundamental transferring characteristics: a single increasing
period, several increasing periods, an increasing quasi-period and almost
noincreasing period. The mechanism of the periodic transference is further
analyzed by determining all long periodic nucleotide strings in the bacterial
and archaeal complete genomes and is explained as follows: both the repetition
of basic periodic nucleotide strings and the transference of non-periodic
nucleotide strings would form the periodic correlation structures with
approximately the same increasing periods.Comment: 23 pages, 6 figures, 2 table
Terminal thermocapillary migration of a droplet at small Reynolds numbers and large Marangoni numbers
In this paper, the overall steady-state momentum and energy balances in the
thermocapillary migration of a droplet at small Reynolds numbers and large
Marangoni numbers are investigated to confirm the quasi-steady state assumption
of the system. The droplet is assumed to have a slight axisymmetric deformation
from a sphere shape. It is shown that under the quasi-steady state assumption,
the total momentum of the thermocapillary droplet migration system at small
Reynolds numbers is conservative. The general solution of the steady momentum
equations can be determined with its parameters depending on the temperature
fields. However, a nonconservative integral thermal flux across the interface
for the steady thermocapillary migration of the droplet at small Reynolds
numbers and large Marangoni numbers is identified. The nonconservative integral
thermal flux indicates that no solutions of the temperature fields exist for
the steady energy equations. The terminal thermocapillary migration of the
droplet at small Reynolds numbers and large Marangoni numbers cannot reach a
steady state and is thus in an unsteady process
Terminal states of thermocapillary migration of a planar droplet at moderate and large Marangoni numbers
In this paper, thermocapillary migration of a planar droplet at moderate and
large Marangoni numbers is investigated analytically and numerically. By using
the dimension-analysis method, the thermal diffusion time scale is determined
as the controlling one of the thermocapillary droplet migration system. During
this time, the whole thermocapillary migration process is fully developed. By
using the front-tracking method, the steady/unsteady states as the terminal
ones at moderate/large Marangoni numbers are captured in a longer time scale
than the thermal diffusion time scale. In the terminal states, the
instantaneous velocity fields in the unsteady migration process at large
Marangoni numbers have the forms of the steady ones at moderate Marangoni
numbers. However, in view of the former instantaneous temperature fields, the
surface tension of the top surface of the droplet gradually becomes the main
component of the driving force on the droplet after the inflection point
appears. It is different from that the surface tension of the bottom surface of
the droplet is the main component of the driving force on the droplet for the
latter ones. The physical mechanism of thermocapillary droplet migration can be
described as the significance of the thermal convection around the droplet is
higher than/just as the thermal conduction across the droplet at large/moderate
Marangoni numbers.Comment: 8 pages, 6 figure
Extension Of Bertrand's Theorem And Factorization Of The Radial Schr\"odinger Equation
The Bertrand's theorem is extended, i.e. closed orbits still may exist for
other central potentials than the power law Coulomb potential and isotropic
harmonic oscillator. It is shown that for the combined potential
(), when (and only when) is the Coulomb
potential or isotropic harmonic oscillator, closed orbits still exist for
suitable angular momentum. The correspondence between the closeness of
classical orbits and the existence of raising and lowering operators derived
from the factorization of the radial Schr\"odinger equation is investigated.Comment: 4 pages, 1 figug
Analysis of correlation structures in the Synechocystis PCC6803 genome
Transfer of nucleotide strings in the Synechocystis sp. PCC6803 genome is
investigated to exhibit periodic and non-periodic correlation structures by
using the recurrence plot method and the phase space reconstruction technique.
The periodic correlation structures are generated by periodic transfer of
several substrings in long periodic or non-periodic nucleotide strings embedded
in the coding regions of genes. The non-periodic correlation structures are
generated by non-periodic transfer of several substrings covering or
overlapping with the coding regions of genes. In the periodic and non-periodic
transfer, some gaps divide the long nucleotide strings into the substrings and
prevent their global transfer. Most of the gaps are either the replacement of
one base or the insertion/reduction of one base. In the reconstructed phase
space, the points generated from two or three steps for the continuous
iterative transfer via the second maximal distance can be fitted by two lines.
It partly reveals an intrinsic dynamics in the transfer of nucleotide strings.
Due to the comparison of the relative positions and lengths, the substrings
concerned with the non-periodic correlation structures are almost identical to
the mobile elements annotated in the genome. The mobile elements are thus
endowed with the basic results on the correlation structures.Comment: 29 pages, 6 figure
- …