In this paper we extend the classical notion of strong and weak backdoor sets by allowing that different instantiations of the backdoor variables result in instances that belong to different base classes; the union of the base classes forms a heterogeneous base class. Backdoor sets to heterogeneous base classes can be much smaller than backdoor sets to homogeneous ones, hence they are much more...

Decreases in plasma bicarbonate are associated with hyperchloremic acidosis and lactic acidosis. According to the Stewart approach to acid-base physiology, the strong-ion difference regulates plasma bicarbonate, with chloride and lactate being the only strong anions routinely measured in clinical chemistry. We hypothesized that the plasma strong-ion difference, both with and without lactate, wo...

The excited-state proton transfer (ESPT) of the strong photoacid, N-methyl-7-hydroxyquinolinium, was studied in the presence of different weak bases such as methanol, ethanol, and dimethyl sulfoxide in an aprotic solvent of acetonitrile. Here, we present chemical kinetics analysis of the ESPT mechanism to explain biphasic fluorescence decay of the parent photoacid and the sign reversal of the r...