Modeling two-state cooperativity in protein folding

A protein model with the pairwise interaction energies varying as local environment changes, i.e., including some kinds of collective effect between the contacts, is proposed. Lattice Monte Carlo simulations on the thermodynamical characteristics and free energy profile show a well-defined two-state behavior and cooperativity of folding for such a model. As a comparison, related simulations for the usual G\={o} model, where the interaction energies are independent of the local conformations, are also made. Our results indicate that the evolution of interactions during the folding process plays an important role in the two-state cooperativity in protein folding.Comment: 5 figure

Induced Technical Change in Centrally Planned Economies

It has generally been assumed that the inferences of the induced technical change model with respect to the direction of technical change could not be expected to hold for the centrally planned economies. In this paper we test three hypotheses generated from the induced technical change hypotheses against the experience of centrally planned economies: (a) if land becomes increasingly scarce new technology will be biased in a land-saving direction; (b) if labor becomes increasingly scarce new technology will be biased in a laborsaving direction; and (c) changes in the land-labor ratio have been induced by changes in relative factor endowments. The results suggest a bias toward mechanical and against biological technology regardless of factor endowments. This is consistent with the well known ideological or policy bias in a number of centrally planned economies toward a capital intensive development strategy.Research and Development/Tech Change/Emerging Technologies,