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Biomedical subjects

F Lara-Ochoa

Publications and source records attributed to F Lara-Ochoa.

20 records · Page 2Linked to original sources

Density dependent diffusional model of an infective population.

In this work, we present a density-dependent diffusional model which, coupled to three different types of growth, permitted us to study the infective potential of a bacteria species. The results show that those species with strong internal competency have the higher colonizing capacity in terms of invasion speed. Here, we also advanced a model for the static spatial inhomogeneous distribution that some species establish after migration. It is proposed that the origin of these patterns is the result of a balance between the dispersal tendency and the attractive behavior. The results obtained were compared with the observed behavior of Rhizobium spp. during infection of leguminous roots. A possible explanation of the observed morphologies of nodule development in different legumes is suggested.

Bacterial Infections↗

(Tetrakis(2-pyridylmethyl)ethylenediamine)iron(II) perchlorate. Study of density functional methods.

On the basis of the data obtained by X-ray diffraction, the properties of two independent crystallographic subsystems in the [Fe(tpen)](ClO4)2.2/3H2O complex are studied in detail with the density functional method B3LYP. The energies of singlet, triplet, and quintet states at different temperatures are obtained, the influences of geometry on energy changes are analyzed, the regularity of the spin-state interconversions is investigated, and the effect of the triplet and action of the anion on spin crossover are discussed. This investigation demonstrates that (1) the energy difference between the high-spin state and singlet state decreases as the Fe-N distance and geometric distortion increase, (2) the spin-equilibrium system is predominantly in low-spin form below room temperature and the proportion of high-spin state rapidly increases above room temperature, (3) one of the two cation sites has a greater presence of the high-spin content, (4) the triplet state may be responsible for the fast rate of spin-state interconversions, and (5) the B3LYP method proves to be very adequate to study the spin-state transition of this complex.

Journal Article↗