The reaction-diffusion basis of animated patterns in eukaryotic flagella
Nature Communications,
Journal Year:
2023,
Volume and Issue:
14(1)
Published: Sept. 27, 2023
The
flagellar
beat
of
bull
spermatozoa
and
C.
Reinhardtii
are
modelled
by
a
minimal,
geometrically
exact,
reaction-diffusion
system.
Spatio-temporal
animated
patterns
describe
waves,
analogous
to
chemical-patterns
from
classical
systems,
with
sliding-controlled
molecular
motor
reaction-kinetics.
system
is
derived
first
principles
as
consequence
the
high-internal
dissipation
flagellum
relative
external
hydrodynamic
dissipation.
Quantitative
comparison
nonlinear,
large-amplitude
simulations
shows
that
account
for
experimental
beating
both
sperm
Reinhardtii.
Our
results
suggest
unified
mechanism
may
exist
motors
controlled
sliding,
without
requiring
curvature-sensing,
uninfluenced
hydrodynamics.
High-internal
instigates
autonomous
travelling
waves
independently
fluid,
enabling
progressive
swimming,
otherwise
not
possible,
in
low
viscosity
environments,
potentially
critical
fertilizers
aquatic
microorganisms.
prove
powerful
tool
studying
pattern
formation
movement
on
structures.
Language: Английский
Multi-time scale control and optimization via averaging and singular perturbation theory: From ODEs to hybrid dynamical systems
Annual Reviews in Control,
Journal Year:
2023,
Volume and Issue:
56, P. 100926 - 100926
Published: Jan. 1, 2023
Multi-time
scale
techniques
based
on
singular
perturbations
and
averaging
theory
are
among
the
most
powerful
tools
developed
for
synthesis
analysis
of
feedback
control
algorithms.
This
paper
introduces
some
recent
advances
in
perturbation
continuous-time
dynamical
systems
modeled
as
ordinary
differential
equations
(ODEs),
well
hybrid
that
combine
dynamics
discrete-time
dynamics.
Novel
multi-time
analytical
higher-order
also
discussed
illustrated
via
different
examples.
In
context
systems,
a
class
sufficient
Lyapunov-based
conditions
global
stability
results
presented.
The
through
various
new
architectures
algorithms
within
adaptive
extremum-seeking
systems.
These
suitable
study
model-free
optimization
stabilization
problems
require
synergistic
use
feedback.
aims
to
acquaint
reader
with
range
modern
studying
phenomena
providing
guidelines
future
research
this
field.
Language: Английский