Government College

About: Government College is a based out in . It is known for research contribution in the topics: Population & Ring (chemistry). The organization has 4481 authors who have published 5986 publications receiving 57398 citations.

N-acetylglucosamine-Mediated Expression of nagA and nagB in Streptococcus pneumoniae

Abstract: In this study, we have explored the transcriptomic response of Streptococcus pneumoniae D39 to N-acetylglucosamine (NAG). Transcriptome comparison of S. pneumoniae D39 wild-type grown in chemically defined medium (CDM) in the presence of 0.5% NAG to that grown in the presence of 0.5% glucose revealed elevated expression of many genes/operons, including nagA, nagB, manLMN, and nanP. We have further confirmed the NAG-dependent expression of nagA, nagB, manLMN, and nanP by β-galactosidase assays. nagA, nagB and glmS are putatively regulated by a transcriptional regulator NagR. We predicted the operator site of NagR (dre site) in PnagA, PnagB, and PglmS, which was further confirmed by mutating the predicted dre site in the respective promoters (nagA, nagB, and glmS). Growth comparison of ΔnagA, ΔnagB, and ΔglmS with the D39 wild-type demonstrates that nagA and nagB are essential for S. pneumoniae D39 to grow in the presence of NAG as a sole carbon source. Furthermore, deletion of ccpA shows that CcpA has no effect on the expression of nagA, nagB, and glmS in the presence of NAG in S. pneumoniae.

Correlation of plasma electron temperature with neutron emission in a low-energy plasma focus

Abstract: Correlation of neutron emission with plasma electron temperature in a low-energy (2.3 kJ) plasma focus is investigated. To determine the plasma temperature by continuum X-ray analysis, cobalt is selected as the filter, which discriminates the line radiation from the background impurities like carbon, nitrogen, and oxygen, or the copper of which plasma focus electrodes are made. For a pressure range of high neutron emission (1-4 mbar), the neutron yield is found to correlate with the plasma temperature. The highest temperature recorded is 5 keV at 2.5 mbar, the filling pressure for the highest neutron emission in this device.

Fluorescence Quenching of 2,2″-dimethyl-p-terphenyl by Carbon Tetrachloride in Binary Mixtures

Abstract: The fluorescence quenching of 2,2″-dimethyl-p-terphenyl (DMT) by carbon tetrachloride (CCl4) was investigated in different solvent mixtures of benzene and acetonitrile at room temperature (300 K). A positive deviation from linearity was observed in the Stern-Volmer plots for all the solvent mixtures. This could be explained satisfactorily by static and dynamic quenching models. The nonlinearities in the S-V plots are interpreted in terms of ground state complex model and the sphere of action static quenching model. The results suggest that positive deviations in the S-V plot are due to the presence of both static and dynamic quenching processes. To explain that bimolecular reactions are diffusion limited, we have used finite sink approximation model. Various rate parameters for the quenching process have been determined by static and dynamic quenching models. The dynamic quenching constant depends on the solvent polarity and indicates that quenching reaction is diffusion limited.

Myricetin attenuates neurodegeneration and cognitive impairment in Parkinsonism.

Abstract: Parkinson's disease (PD) is a progressive neurodegenerative disease due to dopaminergic neuron degeneration. It mostly affects the aged population, leads to memory decline and loss of motor coordination. The present study investigates the neuroprotective role of myricetin a flavonol isolated from the brown seaweed Turbinaria ornata in rotenone induced Drosophila model of PD. Rotenone administration led to dopaminergic neuronal degeneration, dopamine depletion, impaired muscular coordination, gait disturbances, memory decline oxidative stress and apoptosis. Ingestion of myricetin by Drosophila significantly prevented rotenone induced neuronal degeneration. These results confirm that myricetin exerts neuroprotective effect in experimental PD.