Similarity Renormalization Group Evolution of Chiral Effective Nucleon-Nucleon Potentials in the Subtracted Kernel Method Approach

Methods based on Wilson's renormalization group have been successfully applied in the context of nuclear physics to analyze the scale dependence of effective nucleon-nucleon ($NN$) potentials, as well as to consistently integrate out the high-momentum components of phenomenological high-precision $NN$ potentials in order to derive phase-shift equivalent softer forms, the so called $V_{low-k}$ potentials. An alternative renormalization group approach that has been applied in this context is the Similarity Renormalization Group (SRG), which is based on a series of continuous unitary transformations that evolve hamiltonians with a cutoff on energy differences. In this work we study the SRG evolution of a leading order (LO) chiral effective $NN$ potential in the $^1 S_0$ channel derived within the framework of the Subtracted Kernel Method (SKM), a renormalization scheme based on a subtracted scattering equation.Comment: Published versio

A competitive approach for the reduction of unsaturated compounds based on fungal ene-reductases

The aim of this work was to select potential biocatalysts for the reduction of unsaturated compounds. The ability of Gliomastix masseei, Mucor circinelloides, Mucor plumbeus, Penicillium citrinum and Syncephalastrum racemosum to convert structurally diverse substrates was tested, also considering the role of substituents linked to the C=C bond on the process efficiency. All the tested fungi expressed ene-reductase activity when tested with several types of compounds; the ketone derivative was the best substrate, followed by the nitroalkene and the unsaturated aldehyde, whereas the ester was the most recalcitrant to bioreduction. The results highlighted the potential of Mucor circinelloides MUT 44 and Mucor plumbeus MUT 2769 as versatile whole-cell systems; fast and efficient reduction was obtained using these biocatalysts for most of the compounds. Comparative analysis of the substrate spectrum was performed for three Mucor circinelloides strains, and reaction rates and timings were shown to vary, indicating a strong physiological diversity of ene-reductase activity at the intraspecific level