The principal locus for binding interactions between the aspartate and serine receptors of escherichia coli and the methyltransferase was found to be in the last five amino acids of the receptor. The thermodynamic parameters of transferase-receptor interactions were determined by isothermal titration calorimetry. the serine receptor and three C-terminal fragments (C-fragments) of the aspartate receptor consisting of ether the last 297, 88, or 38 amino acids gave comparable values for binding (n=1, deltaH approximately 13 kcal/mol, and Ka approximately 4 x 10(5)M-1). Truncating either 16 or 36 amino acids form the C-terminus eliminated observable interactions. Finally the pentapeptide Asn-Trp-Glu-Thr-Phe, which corresponds to the last five amino acids of the receptor and is strictly conserved among E. coli serine amd aspartate receptors and the Salmonella typhimurium aspartate receptor, was found to have all the binding activity of the full-length receptor and the C-fragments. An in vitro methylation assay was used to obtain evidence for the physiological significance of this interaction in which excess peptide was able to completely block receptor methylation. The location of the binding site far from the methylation sites in the primary structure of the receptor suggests that the principle role of this interaction may be to hold the transferase in close proximity to all the methylation sites. Intersubunit methylation implication is proposed as plausible consequence of this "controlled proximity" mechanism since the ribose-galactose and dipeptide receptors lack the transferase binding sequence, and appear unable to bind transferase. Intersubunit methylation implies that transferase bound to eother the serine or aspartate receptor subunit may catalyze methylation of receptor subunits in a neighboring dimer, including those that have ligand specificity.

Over the past decades, organic-inorganic hybrid polymers have been applied in different fields, including the adsorption of pollutants from wastewater and solid-state separations. In this review, firstly, these compounds are classified. These compounds are prepared by sol-gel method, self-assembly process (mesopores), assembling of nanobuilding blocks (e.g., layered or core-shell compounds) and as interpenetrating networks and hierarchically structures. Lastly, the adsorption characteristics of heavy metals of these materials, including different kinds of functional groups, selectivity of them for heavy metals, effect of pH and synthesis conditions on adsorption capacity, are studied.

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The effective temperature (ET) is employed to investigate observed changes of thermal comfort conditions over China during the late decades of the historical observational period. ET considers the aggregate effects of temperature, relative humidity, and wind speed to describe the human thermal sensitivity to weather and climate. The data used in the study is the recently produced gridded daily scale dataset CN05.1, which covers the period of 1961–2014 at a resolution of 0.25° latitude by 0.25° longitude. Results show a general increase of ET in both December‐January‐February (DJF) and June‐July‐August (JJA). The increase is mostly caused by an increase of temperature and a decrease of wind speed, while the contribution from relative humidity is small. As measured by ET, China is a cold country with many more cold days than hot days. Large decreases of cold days and increases of hot days are found following the increase of ET. The number of comfortable days shows larger values in the warm areas and during the warm seasons. During the analysis period, the number of annual comfortable days shows an increasing trend when considering the China‐wide average. However, the number of annual comfortable days during JJA decreases over warm areas.

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In this study, gaseous ozone was used as a fungicide to preserve stored wheat. The following operating parameters were investigated for their effects on the fungicidal efficacy of ozone: (1) the applied ozone dose; (2) ozonation time; (3) water activity of the wheat; and (4) temperature of the wheat. The effect of ozonation on germination of the wheat was also studied. Experimental results revealed that gaseous ozone was very effective in the inactivation of fungi associated with the wheat. Within 5 min of ozonation, 96.9% of the fungal spores were inactivated by applying 0.33 mg of ozone (g wheat) −1 min −1 . It was also found that increases in both water activity and temperature of the wheat enhanced the fungicidal efficacy of ozone. In addition, results of this study indicated that the inactivation processes could be controlled by simply monitoring the ozone exiting from the reactor and, consequently, the time-consuming microbial examination processes could be avoided. This finding would make the application of ozone in the preservation of cereal grains easier, simpler, and more cost-effective. It was also found that although the applied ozone doses above certain thresholds may reduce the germination of wheat, the inactivation of fungi could be achieved using applied ozone doses far below those thresholds.