The sleep and respiration of 88 infants were recorded for 24-h periods on the first 2 postnatal days and again at 6 months. The recordings were made with the Motility Monitoring System, which does not require instrumentation of the infants. Quiet sleep respiration rates (QSRR) increased over the first 2 days (mean = 42.2, SD = 1.0 and mean = 44.5, SD = 1.1, respectively), then decreased by 6 mo...

Quantitative structure–retention relationships (QSRR) have been derived for prediction of RP-HPLC retention of peptides obtained by online digestion of myoglobin. To characterize the structure of a peptide quantitatively, and then to predict its retention time under gradient HPLC conditions, the structural descriptors used were: the logarithm of the sum of retention times of the amino acids of ...

Quinone molecules are intracellular electron-transport carriers, as well as critical intra- and extracellular signals. However, transcriptional regulation of quinone signaling and its molecular basis are poorly understood. Here, we identify a thiol-stress-sensing regulator YodB family transcriptional regulator as a central component of quinone stress response of Staphylococcus aureus, which we ...

The predictive capability of the retention time prediction model based on quantitative structure-retention relationships (QSRR) was tested. QSRR model was derived with the use of set of peptides identified with the highest scores and originated from 8 known proteins annotated as model ones. The predictive ability of the QSRR model was verified with the use of a Bacillus subtilis proteome digest...

In this paper, a novel approach is described for the a priori prediction of protein retention in ion exchange systems. Quantitative structure retention relationship (QSRR) models based on a genetic algorithm/partial least squares approach were developed using experimental chromatographic data in concert with molecular descriptors computed using protein crystal structures. The resulting QSRR mod...

In this study, quantitative structure-retention relationship (QSRR) methodology employed for modeling of the retention times of 16 banned pesticides in nano-liquid chromatography (nano-LC) column. Genetic algorithm-multiple linear regression (GA-MLR) method employed for developing global and consensus QSRR models. The best global GA-MLR model was established by adjusting GA parameters. Three de...

To relate structure and chromatographic retention an approach is needed that lacks the rigour of thermodynamics but which provides otherwise inaccessible information. Such an approach is a combination of detailed models with certain thermodynamic concepts. Linear free-energy relationships (LFER) may be regarded as linear relationships between the logarithms of the rate or equilibria constants f...

The transcriptional regulator QsrR is converted into a genetically encoded fluorescent probe capable of ratiometric monitoring of quinones in living cells with high sensitivity and selectivity.

Organic compounds containing heteroatoms or multiple bonds can be conveniently represented as vertex- and edge-weighted molecular graphs. These atom and bond parameters can be computed for any organic compound with two parameter sets that we have recently defined, namely, the relative electronegativity X and the relative covalent radius Y weighting schemes. Structural descriptors computed with ...

Enamides with a free NH group have been evaluated as nucleophiles in chiral Brønsted acid-catalyzed enantioselective α-amidoalkylation reactions of bicyclic hydroxylactams for the generation of quaternary stereocenters. A quantitative structure-reactivity relationship (QSRR) method has been developed to find a useful tool to rationalize the enantioselectivity in this and related processes and t...