Cyclobutane dimer photolyases are proteins that bind to UV-damaged DNA containing cyclobutane pyrimidine dimer lesions. They repair these lesions by photo-induced electron transfer. The electron donor cofactor of a photolyase is a two-electron-reduced flavin adenine dinucleotide (FADH(-)). When FADH(-) is photo-excited, it transfers an electron from an excited pi --> pi* singlet state to the py...

Total dissociative electron attachment cross sections are presented for the amino acids, glycine, alanine, proline, phenylalanine, and tryptophan, at energies below the first ionization energy. Cross section magnitudes were determined by observation of positive ion production and normalization to ionization cross sections calculated using the binary-encounter-Bethe method. The prominent 1.2 eV ...

We overview our recent theoretical predictions and the innovative experimental findings that inspired us concerning the mechanisms by which very low-energy (0.1-2 eV) free electrons attach to DNA and cause strong (ca. 4 eV) covalent bonds to break causing so-called single-strand breaks. Our primary conclusions are that (i) attachment of electrons in the above energy range to base pi* orbitals i...

In this paper some upper and lower bounds for the greatest eigenvalues of the PI and vertex PI matrices of a graph G are obtained. Those graphs for which these bounds are best possible are characterized.

The reaction 3-hydroxybutyrate (3-OH-butyrate) + 2 cytochrome c + ~ + 2 ADP + 2 Pi acetoacetate + 2 cytochrome e+’ + 2 ATP was used to study the energy relationships of electron transfer in the forward and reverse directions in suspensions of isolated rat liver mitochondria. Reduction of cytochrome c was monitored continuously at 550-540 nm while aliquots were taken to measure transmembrane pH ...

Metal-thiolate active sites play major roles in bioinorganic chemistry. The M--S(thiolate) bonds can be very covalent, and involve different orbital interactions. Spectroscopic features of these active sites (intense, low-energy charge transfer transitions) reflect the high covalency of the M--S(thiolate) bonds. The energy of the metal-thiolate bond is fairly insensitive to its ionic/covalent a...

renewable energy sources like wind, sun, and hydro are considered as a reliable alternative to the traditional energy sources such as oil, natural gas, or coal. this paper describes modeling and simulations to determine a method for the power performance evaluation of autonomous wind turbine system. a speed control regulator is utilized to control the dc bus voltage. the inverter gate’s signals...

We determined the anisotropic dielectric response of graphite by means of time-dependent density-functional theory and high-resolution valence electron energy-loss spectroscopy. The calculated loss function was in very good agreement with the experiment for a wide range of momentum-transfer orientations with respect to the graphitic basal planes, provided that local-field effects were included ...