The non-specific solvent effects in neutral dipolar (or better yet, effective dipolar) solvents were discussed in the literature with success. However the situation is not so clear when the solvent is an electrolyte, where the reaction field approach is no longer valid. In the present communication we present a theory based on the Mean Spherical Scaling Approximation in which the system is enca...

Local exchange-correlation functionals are defined for different systems with spherical symmetry, by requiring that they reproduce the correct exchange-correlation energy and exchange-correlation potential (up to a constant). For comparison, the results with the uniform electron gas local density approximation and a generalized gradient approximation are also shown. q 2000 Elsevier Science B.V....

Various mechanisms for the alkaline hydrolysis of aza-b-lactam (na), oxo-b-lactam (oa) and thio-b-lactam compounds (sa) were analysed on the basis of PM3 calculations in order to identify potential differences with classical b-lactam antibiotics. Changes in the tetrahedral intermediate were studied via the cleavage of not only the bond between atoms at 7 and 4 as in classical b-lactam antibioti...

We have investigated linear, starbranched and hyperbranched XnHm polymers and determined the number of atoms, rotors, internal coordinates, valence and HOMO molecular orbitals as well as molecular mass for each generation and valency. We use the semi-empirical MNDO model to obtain full geometry optimization for increasingly larger clusters for each generation in order to obtain total relative e...

The hydrogen bond interaction between acetone and water is investigated at the ab initio MBPT/CC levels using different approximations and basis sets. At the highest level the binding energy is obtained as 5.6 kcal mol. Analysis of the electron correlation effects shows only a very mild influence on the binding energy. Study of the blue shift of the n! p transition of acetone in water shows tha...

Nichols, B. W. (1968)Lipids 3,354360 Nichols, B. W. & Wood, B. J. B. (1968) Nature (London) 217,767-768 Rosenberg, A. & Pecker, H. (1964) Biochemistry 3,254-258 Sastry, P. S. & Kates, M. (1964a) Biochemistry 3, 1271-1280 Sastry, P. S. & Kates, M. (19646) Biochemistry 3, 1280-1287 Schiff, J. A. & Hodson, R. C. (1973) Annu. Rev. Plant Physiol. 24,381414 Schmidt, A. (1976) Planta 130,257-264 Shaw,...

development of inhibitor to factor viii is the most serious complication of hemophilia therapy. to determine the prevalence of inhibitors in iran hemophilia a patients exposed to blood products, 1280 hemophilia a patients (age range 9 months-84 years) were evaluated. all patients received several blood products such as fresh frozen plasma (ffp), cryoprecipitate, and factor viii. 635 of 1280 pat...