The classical Monod-Wyman-Changeux model for homogeneous allosteric protein complex is generalized in this article to model the responses of heterogeneous receptor complexes to multiple types of ligand stimulus. We show that the recent in vivo experimental data of Escherichia coli chemotaxis responses for mutant strains with different expression levels of the chemo-receptors to different types ...

Using a formalism developed by Polychronakos, we explicitly construct a set of invariants of the motion for the Haldane-Shastry SU(N) chain. Submitted to Physical Review Letters, PACS numbers: 75.10.Jm, 05.30.-d, 03.65.Ca † [email protected] ‡ [email protected] There have been several recent papers on the Haldane-Shastry model for spin chains and its SU(N) generalizat...

In these lectures, I review some recent results on the Calogero-Sutherland model and the Haldane Shatry-chain. The list of topics I cover are the following: 1) The Calogero-Sutherland Hamiltonien and fractional stastistics. The form factor of the density operator. 2) The Dunkl operators and their relations with monodromy matrices, Yangians and aane-Hecke algebras. 3) The Haldane-Shastry chain i...

Using the valence-bond-solid (VBS) approach and the Schwinger boson mean field approximation, we study the dependence of the Haldane gap of a spin-1 linear chain Heisenberg antiferromagnet on impurity doping with different spins. The impurity spins affect the singlet pairing order parameter ∆ and the constraint factor λ. As a result, the Haldane gap is reduced by a factor ∼ n 2/3 i , with ni as...

The validity of the Michaelis-Menten-Briggs-Haldane approximation for single enzyme reactions has recently been improved by the formalism of the total quasi-steady-state approximation. This approach is here extended to fully competitive systems, and a criterion for its validity is provided. We show that it extends the Michaelis-Menten-Briggs-Haldane approximation for such systems for a wide ran...

Jacques Monod and Francois Jacob, our heroes, described a gene-regulatory world run exclusively by repressors. The activities of repressors, their abilities to bind DNA as we later learned, would be controlled — helped or hindered — by small molecules that bind these proteins. They showed [1] that networks of considerable complexity could be created with such a regulatory system. There was no n...

Some of these studies have been reported in a preliminary communication, Hoffee, P., and E. Englesberg, Bacteriol. Proc., 1962, p. 120. Abbreviations: ATP, adenosine triphosphate; aMG, alpha methyl D-glucopyranoside. t Predoctoral Research Fellow, U.S. Public Health Service. l Rickenberg, H. V., G. N. Cohen, G. Buttin, and J. Monod, Ann. Inst. Pasteur, 91, 829 (1956). 2 Cohen, G. N., and J. Mon...

We show how a particular spatial structure with a buffer globally stabilizes the chemostat dynamics with non-monotonic response function, while this is not possible with single, serial or parallel chemostats of the same total volume and input flow. We give a characterization of the set of such configurations that satisfy this property, as well as the configuration that ensures the best nutrient...

We generalize the collision term in the one-dimensional Boltzmann-Nordheim transport equation for quasiparticles that obey the Haldane exclusion statistics. For the equilibrium situation, this leads to the " golden rule " factor for quantum transitions. As an application of this, we calculate the density response function of a one-dimensional electron gas in a periodic potential, assuming that ...