Wavelet method for steady state immobilized enzyme kinetic model: an operational matrix approach

2021 ◽  
Author(s):  
G. Hariharan ◽  
S. Padma
Keyword(s):  
Steady State ◽  
Kinetic Model ◽  
Immobilized Enzyme ◽  
Operational Matrix ◽  
Enzyme Kinetic ◽  
Matrix Approach ◽  
Wavelet Method

Photophosphorylation as Function of ADP Concentration at Varying Transmembrane Proton Gradients

1989 ◽  
Vol 44 (5-6) ◽  
pp. 473-479 ◽  
Author(s):  
Georg Heinen ◽  
Heinrich Strotmann
Keyword(s):  
Steady State ◽  
Kinetic Model ◽  
Light Intensity ◽  
Phosphate Concentration ◽  
Proton Gradient ◽  
Enzyme Kinetic ◽  
Fluorescence Technique ◽  
Proton Gradients ◽  
Atp Formation ◽  
External Ph

Abstract Rates of photophosphorylation were measured at constant saturating phosphate concentration , varying ADP concentration , and varying light intensity. As the transmembrane proton gradient is decreased by phosphorylation to different extents depending on the concentration of ADP . rates of ATP formation obtained at the different ADP concentrations were plotted versus the actual steady state ΔpH (in the absence of ΔΨ) during the course of the reaction . ΔpH was monitored by the calibrated 9-aminoacridine fluorescence technique. In secondary plots phosphorylation as function of ADP concentration at different constant ΔpH values were obtained . The results indicate Michaelis-Menten kinetics. The true Km for ADP is virtually unaffected by ΔpH whereas Vmax (at ADP saturation ) strongly depends on ΔpH . The results are discussed in the framework of a simple enzyme kinetic model which considers the intrathylakoidal proton (at constant external pH ) as a third substrate for ATP formation. The model is capable o f explaining the reported results as well as a variety of important results from the literature.

Kinetic analysis of mechanism of intestinal Na+-dependent sugar transport

1985 ◽  
Vol 248 (5) ◽  
pp. C498-C509 ◽  
Author(s):  
D. Restrepo ◽  
G. A. Kimmich
Keyword(s):  
Experimental Data ◽  
Steady State ◽  
Sugar Transport ◽  
Enzyme Kinetic ◽  
Steady State Distribution ◽  
State Distribution ◽  
Least Squares Fit ◽  
Coupling Stoichiometry ◽  
Rate Limiting ◽  
Kinetics Of

Zero-trans kinetics of Na+-sugar cotransport were investigated. Sugar influx was measured at various sodium and sugar concentrations in K+-loaded cells treated with rotenone and valinomycin. Sugar influx follows Michaelis-Menten kinetics as a function of sugar concentration but not as a function of Na+ concentration. Nine models with 1:1 or 2:1 sodium:sugar stoichiometry were considered. The flux equations for these models were solved assuming steady-state distribution of carrier forms and that translocation across the membrane is rate limiting. Classical enzyme kinetic methods and a least-squares fit of flux equations to the experimental data were used to assess the fit of the different models. Four models can be discarded on this basis. Of the remaining models, we discard two on the basis of the trans sodium dependence and the coupling stoichiometry [G. A. Kimmich and J. Randles, Am. J. Physiol. 247 (Cell Physiol. 16): C74-C82, 1984]. The remaining models are terter ordered mechanisms with sodium debinding first at the trans side. If transfer across the membrane is rate limiting, the binding order can be determined to be sodium:sugar:sodium.

Numerical study of stochastic Volterra–Fredholm integral equations by using second kind Chebyshev wavelets

2016 ◽  
Vol 24 (2) ◽  
Author(s):  
Fakhrodin Mohammadi ◽  
Parastoo Adhami
Keyword(s):  
Integral Equations ◽  
Numerical Study ◽  
Operational Matrix ◽  
Computational Method ◽  
Fredholm Integral Equations ◽  
Wavelet Method ◽  
Chebyshev Wavelets ◽  
Block Pulse Functions ◽  
Stochastic Operational Matrix ◽  
Efficiency And Reliability

AbstractIn this paper, we present a computational method for solving stochastic Volterra–Fredholm integral equations which is based on the second kind Chebyshev wavelets and their stochastic operational matrix. Convergence and error analysis of the proposed method are investigated. Numerical results are compared with the block pulse functions method for some non-trivial examples. The obtained results reveal efficiency and reliability of the proposed wavelet method.

Serial analysis of renal blood flow by positron tomography with rubidium-82

1986 ◽  
Vol 251 (5) ◽  
pp. H1024-H1030
Author(s):  
N. Tamaki ◽  
C. A. Rabito ◽  
N. M. Alpert ◽  
T. Yasuda ◽  
J. A. Correia ◽  
...  
Keyword(s):  
Blood Flow ◽  
Steady State ◽  
Kinetic Model ◽  
Renal Blood Flow ◽  
Constant Infusion ◽  
Flow Reduction ◽  
Arterial Blood ◽  
Steady State Kinetic ◽  
State Kinetic ◽  
Rubidium 82

To determine whether renal blood flow can be measured by positron-emission tomography (PET) during constant infusion of rubidium-82 (82Rb) using a steady-state kinetic model, studies were performed in 10 dogs at control (n = 10), during mild flow reduction (n = 7), during severe flow reduction (n = 10), and after reperfusion of the kidney (n = 3). PET data were quantified to determine mean concentration of 82Rb (Ct) in each transverse section of the kidney. The arterial concentration (Ca) of 82Rb was measured by well counting of arterial blood samples during the equilibrium scan. 82Rb renal uptake (Ct/Ca) correlated nonlinearly with microsphere renal blood flow according to a steady-state kinetic model (r = 0.90). 82Rb estimated flow was 3.16 +/- 1.36 ml X min-1 X g-1 at control and 1.56 +/- 0.57 and 0.37 +/- 0.59 during mild and severe flow reductions, respectively. Microsphere determined flow was 2.89 +/- 0.77 ml X min-1 X g-1 at control, 1.58 +/- 0.42 at mild reduction, and 0.27 +/- 0.49 at severe reduction. In the occlusion and reperfusion model, the 82Rb estimated flow during occlusion was 0.21 +/- 0.15 ml X min-1 X g-1 and on reperfusion went up to 2.13 +/- 1.08. The contralateral kidney demonstrated reductions in the 82Rb estimated flow of 3.02 +/- 1.62 ml X min-1 X g-1 (63%) and 2.92 +/- 0.89 (61%) during mild and severe flow reductions, respectively. We conclude that PET with 82Rb permits serial quantitative assessment of renal flood flow.

Modified wavelet method for solving fractional variational problems

2020 ◽  
pp. 107754632093202
Author(s):  
Haniye Dehestani ◽  
Yadollah Ordokhani ◽  
Mohsen Razzaghi
Keyword(s):  
Error Analysis ◽  
Operational Matrix ◽  
Approximate Solutions ◽  
Variational Problems ◽  
High Accuracy ◽  
Construction Method ◽  
Computational Method ◽  
Wavelet Method ◽  
Fractional Variational Problems ◽  
Operational Matrix Of Integration

In this article, a newly modified Bessel wavelet method for solving fractional variational problems is considered. The modified operational matrix of integration based on Bessel wavelet functions is proposed for solving the problems. In the process of computing this matrix, we have tried to provide a high-accuracy operational matrix. We also introduce the pseudo-operational matrix of derivative and the dual operational matrix with the coefficient. Also, we investigate the error analysis of the computational method. In the examples section, the behavior of the approximate solutions with respect to various parameters involved in the construction method is tested to illustrate the efficiency and accuracy of the proposed method.

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