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Novel size effect in mesoscopic chemical oscillation systems. Zhonghuai Hou ( 侯中怀 ) Sep. 2008, Hefei Department of Chemical Physics Hefei National Lab for Physical Sciences at Microscale University of Science & Technology of China. Our Research Interests. - PowerPoint PPT Presentation
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Novel size effect in mesoscopic chemical oscillation systems
Zhonghuai Hou ( 侯中怀 )Sep. 2008, Hefei
Department of Chemical PhysicsHefei National Lab for Physical Sciences at Microscale
University of Science & Technology of China
Our Research Interests
Nonlinear Dynamics in Mesoscopic Chemical Systems
Dynamics of Complex Networks Nonequilibrium Thermodynamics of Small
Systems (Fluctuation Theorem) Multiscale Modeling of Complex Systems
Nonequilibrium +Nonlinear+ Complexity
Outline
Introduction the question
Optimal Size Effect
Stochastic Normal Form Theory
Conclusion
Genetic Toggle Switch
In E. ColiNature 2000
Two or more stable states under same external constraints
Reactive/Inactive bistabe
CO+O2 on Pt filed tipPRL1999
Travelling/Target/Spiral/Soliton … waves
PEEM Image CO Oxidation on Pt
PRL 1995
Calcium Spiral Wave in Cardiac Tissues
Nature 1998
Temporally Periodic Variations of Concentrations
Rate OscillationCO+O2 Nano-particle C
atal.Today 2003
Synthetic transcriptional oscillator (Repressilator)
Nature 2002
Stationary spatial structures in reaction-diffusion systems
Cellular PatternCO Oxidation on Pt
PRL 2001
Turing PatternBZ Reaction System
PNAS 2003
Oscillation Multistability Patterns Waves Chaos
Nonlinear Chemical Dynamics
far-from equilibrium, self-organized, complex, spatio-temporal structures
Aperiodic/Initial condition sensitivity/strange attractor…
Strange AttractorThe Lorenz System
Chemical turbulenceCO+O2 on Pt Surface
Science 2001
Collective behavior involving many molecular
unitsMacroscopic state: ( , )tX r
Microscopic state: ,N Nq p
Nonequilibrium Statistical Mechanics
Sub-cellular reactions
- gene expression- ion-channel gating- calcium signaling … …
Heterogeneous catalysis
- field emitter tips- nanostructured composite surface- small metal particles
Mesoscopic Reaction SystemN, V(Small)
Molecular Fluctuation
22 1 1orX X
X V N
Nonlinear Chemical Dynamics? Chemical Oscillation
Regularity Stochasticity
Noise Induced Pattern Transition
Z.Hou, et al., PRL 81, 2854 (1998)
Disorder sustained spiral waves
Z.Hou, et al., PRL 89, 280601 (2002)
We already know ... Noise and disorder play constructive
roles in nonlinear systems
Taming Chaos by Topological Disorder
F. Qi, Z.Hou, H. Xin, PRL 91, 064102 (2003)Y. Gong,Z.Hou, H.Xin. ChemPhysChem 6 , 1042 ( 2005 ); M. M.Wang, Z.Hou, H.Xin. ChemPhysChem7 , 579( 2006);
Ordering Bursting Chaos in Neuron Networks
Modeling of Chemical Oscillations
Macroscopic level: Deterministic, Cont.
N Species, M reaction channels, well-stirred in VReaction j:
j X X v Rate:
( ) jW VX
1
( ( ))( ( ) )
Mji
ij ij
W td X t VF
dt V
XX
Oscillation
Co
nce
ntr
atio
n
Control parameter
Hopf Bifurcation
Stale focus
Hopf bifurcation leads to oscillation
: 0
loses stabilityS S
S
X F X
X
has a pair of
pure imaginary eigenvalues
ij J F X
Modeling of Chemical Oscillations
Mesoscopic Level: Stochastic, Discrete
1
;; ;
M
j j j jj
P tW P t W P t
t
X
X ν X ν X XMaster Equation
Kinetic Monte Carlo Simulation (KMC)Gillespie’s algorithm
Exactly
( , )j
Approximately 1 2
1 1
1 ( )
M Mj ji
ij ij jj j
W WXdt
dt V V VV
X X
Chemi cal Langevi n Equati on (CLE)
V Deterministic equation
Internal Noise
New: Noise Induced Oscillation
1.4 1.6 1.8 2.0 2.2 2.4 2.60.4
0.8
1.2
1.6
2.0
2.4
2.8
Con
cent
ratio
n X
1
Control parameter B
V=1E4
Stochastic OscillationA=1, B=1.95
0.0 0.4 0.8 1.2 1.6 2.010-16
10-14
10-12
10-10
10-8
10-6
10-4
10-2
Frequency (Hz)
Pow
er
FFT
A model system: The Brusselator
1.4 1.6 1.8 2.0 2.2 2.4 2.60.4
0.8
1.2
1.6
2.0
2.4
B=2.2 Oscillation
Con
cent
ratio
n X
1
Control parameter B
Hopf Bifurcation
B=1.9 Stale focus
A=1DeterministicStochastic
Noisy Oscillation
Optimal System Size
:
2 :
Peak Height HSNR
Width at H
Optimal System size for mesoscopic chemical oscillation Z. Hou, H. Xin. ChemPhysChem 5, 407(2004)
Best performance
Seems to be common … Internal Noise Stochastic Resonance in a Circadian Clock System J.Che
m.Phys. 119, 11508(2003)
Optimal Particle Size for Rate Oscillation in CO Oxidation on Nanometer-Sized Palladium(Pd) Particles
J.Phys.Chem.B 108, 17796(2004)
Internal Noise Stochastic Resonance of synthetic gene network Chem.Phys.Lett. 401,307(2005)
Effects of Internal Noise for rate oscillations during CO oxidation on platinum(Pt) surfaces J.Chem.Phys. 122, 134708(2005)
System size bi-resonance for intracellular calcium signaling ChemPhysChem 5, 1041(2004)
Double-System-Size resonance for spiking activity of coupled HH neurons ChemPhysChem 5, 1602(2004)
? Common mechanism
Analytical Study
Analytical study Main idea
Fact: all happens close to the HB
Question: common features near HB?
Answer: normal form on center manifold
Analytical study
1
1: ( ) ( ) ( )
M
j j jjCLE dX F dt v w dW t
V X X
Stochastic Normal Form
3
20
1( )
1( )
r rj jj
i j jj
dr r C r dt dWV
d C r dt dWV
S
X
FJ
X
0 i
) ,1( iba
baT
01
S
S
XX
XXT
y
x
22
111
iZ x iy re
0, for 0, /( )
finite, and coupled via noiserV r C
V r
jjjj
jjjrj
w
w
)sin~cos~(
)sin~cos~(
12
21
Analytical study Stochastic Averaging
3
20
2r r
i
dr r C r dt dWVr V
d C r dt dWr V
2 2 2 (00)1 2( ) / 2 : system dependent
and are de-coupled Solvable
j j jjw
r
Analytical study(…) Probability distribution of r
2
3 2 2( , )2
2r r r
r tr C r Vr
t V
2 4
0 2
2( , )0 ( ) exp
2r
s
r C rr tr C r
t V
3 2( , )0 2 0 s
r
r tr C r Vr
r
1/ 22 2even for <0, 2 / ( 2 )s r rr C V C
Fokker-Planck
equation
Stationary distribution
Most probable radius
Noise induced
oscillation
Analytical study(…) Auto-correlation function
12 21( ) lim ( ) ( ) 2t sCorr r r t r t r e V
21
1( ) lim cos ( )cos ( ) cos( )
2tCorr t t e
2 221/ 4 /c sVr
Correl ati on Ti me:
( ) lim ( ) ( ) ( )* ( )tC x t x t Corr r Corr
Analytical study(…) Power spectrum and SNR
22
2 202 1
( ) 2 ( )( )
i srPSD C e d
2 2 4 21 0 2
22 22
2
2
p i s s s
s s c
C r H r r V
Vr SNR H r
2 2
4( )0 r
opt
CSNRV
V
Optimal system size:
Analytical study(…) 3
20
2r r
i
dr r C r dt dWVr V
d C r dt dWr V
Universalnear HB
2 22 / 2s r rr C V C
2 2
21/ 4 /c sVr , ,s cV r
2/ s cSNR H r
2 24 /opt rV C 2 2 2 (00)
1 2( ) / 2j j jjw
System Dependent
ChemPhysChem 7, 1520(July 2006) ; J. Phys.Chem.A 111, 11500(Nov. 2007); New J. Phys. 9, 403(Nov. 2007) ;
System Size Bi-resonance
System Size Biresonance for Intracellular Calcium SignalingJ. Zhang, Z.H.Hou, H.W.Xin, ChemPhysChem 5, 1041(2004)
Effects of Internal Noise for Rate Oscillation During CO Oxidation
Z.Hou, T. Rao, H.Xin. J.Chem.Phys. 122 , 134708(2005)
System Size Bi-resonance
N 个 HH 神经元的耦合体系……S S S S
N
3 41 1( ) ( ) ( ) ( 2 )i
Na i i Na K i i K L i L i i i
dUC g m h U U g n U U g U U I U U U
dt
( )(1 ) ( ) ( )i i i
i x i x i xx U x U x t
, , and 1x m n h i N
Log(S)
Coupled Neuron Network: ChemPhysChem 5 , 1062(2004)
Coupled Calcium Oscillation: Phye.Rev.E 74 031901(2006)
Double System Size Resonance
Summary In mesoscopic chemical systems, molecular fluctua
tions can induce oscillation even outside the deterministic oscillatory region
Optimal system size exists, where the noise-induced oscillation shows the best performance, characterized by a maximal SNR, a trade off between strength and regularity
Based on stochastic normal form, analytical studies show rather good agreements with the simulation results, uncovering the mechanism of NIO and OSS
System Bi-Resonance and Double System Size Resonance are observed
Acknowledgements
Supported by: National science foundation (NSF)
Prof. Yubing Gong ( 龚玉兵 鲁东大学 )
Prof. Jiqian Zhang ( 张季谦 安徽师范大学 )
Maosheng Wang ( 汪茂胜 安徽师范大学 )
Zhiwei Wang ( 王志伟 天津科技大学 )
Tiejun Xiao ( 肖铁军 )
Juan Ma( 马娟 )
Ting Rao( 饶汀 )