Cooperative mechanism

A. Cooper, Mechanism of the benzidine rearrangement, Ph. D. Thesis, London, 1966. 

Siegman, M.J., Butler, T.M., Vyas, T., Mooers, S.U., Narayan, S. (1991). Cooperative mechanisms in the regulation of smooth muscle contraction. In Regulation of Smooth Muscle Contraction (Moreland, R.S., ed.), pp. 77-85. Plenum, New York. 

The HKR reactions follow the cooperative bimetallic catalysis where epoxide and nucleophile activate simultaneously by two different (salen)Co-AlX3 catalyst molecules. The linking of two (salen)Co unit through the A1 induces the cooperative mechanism, albeit through a far less enantio-discriminating transition state than that attained with the catalyst la and la (Scheme2). 

Ohl L, Henning G, Krautwald S, et al. Cooperating mechanisms of CXCR5 and CCR7 in development and organization of secondary lymphoid organs. J Exp Med 2003 197 1199-1204. 

DMT, TMT, DBT, TBT and DPhT chlorides exhibited in vitro spindle disturbance in V79 Chinese hamster cells of brain tubulin. The V79 cells lose stainable spindles at higher concentration. The cell mitosis activity effect at low concentration increased with the lipophilicity of the OTC, but all compounds showed a concentration dependence on microtubules. The OTC seem to act through two different cooperative mechanisms inhibition of microtubule assembly and interaction with hydrophobic sites. The latter mechanism might involve Cl/OH ion exchange28. 

Figure 2.48 Possible cooperative mechanism of crystal-crystal transition from (a) trans planar form III of sPP into (c) isochiral helical form II. Transition occurs through formation of (b) intermediate conformationally disordered modifications containing kink bands, characterized by helical sequences having same chirality (R = right-handed helix). Formation of helical sequences of opposite chirality (right- and left-handed) produces (if) steric interactions between neighboring chains.

Calculations support a cooperative mechanism for the hydration of formaldehyde, acetaldehyde, acetone, and cyclohexanone in water. The results are supported by determination of the rate constant for the neutral hydration of acetone, using labelled acetone and water. Conclusions include ... 

Sq transition are the same for one-photon or cooperative mechanism of S2 state excitation. 

The phase transition consists of a cooperative mechanism with charge-ordering, anion order-disorder, Peierls-like lattice distortion, which induces a doubled lattice periodicity giving rise to 2 p nesting, and molecular deformation (Fig. 11c). The high temperature metallic phase is composed of flat EDO molecules with +0.5 charge, while the low temperature insulating phase is composed of both flat monocations... 

An isolated cs plane or a random array of cs planes, known as the Wadsley defect, still gives rise to nonstoichiometry. Regularly recurring cs planes result in a homologous series of stoichiometric intermediate phases. Occurrence of such equidistant cs planes in a crystal indicates a cooperative mechanism. The formula of a cs phase depends on the cs plane index as well as the width of the parent slab between cs planes. If MO is the formula of the parent line phase, the formula of the homologous series of oxides resulting from cs may be represented as where n is the width (number of... 

The possibility to calculate the anomalous properties of water quantitatively with a simple two step function of the orientations partition function of water molecules gives the possibility to estimate the size of the network of H-bonded molecules in liquid water too. We have to take into account the cooperative mechanism of H-bonds and the preference of C2v symmetry of intermolecular arrangements in... 

In this paper, we investigate our two-band model for the explanation the multi-gap superconductivity of MgB2. We apply the model to an electron-phonon mechanism for the traditional BCS method, an electron-electron interaction mechanism for high- Tc superconductivity, and a cooperative mechanism in relation to multi-band superconductivity. 

This led Stanley to propose the bimetallic cooperativity mechanism shown in Scheme 16. The key bimetallic cooperativity step involves rotation about the central bridging methylene group to give a H /CO double-bridged intermediate (or transition state) species, which directly leads to an... 

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