High Activity Mutants of Butyrylcholinesterase for Cocaine Hydrolysis

Butyrylcholinesterase (BChE) polypeptide variants of the presently-disclosed subject matter have enhanced catalytic efficiency for (−)-cocaine, as compared to wild-type BChE. Pharmaceutical compositions of the presently-disclosed subject matter include a BChE polypeptide variant having an enhanced catalytic efficiency for (−)-cocaine. A method of the presently-disclosed subject matter for treating a cocaine-induced condition includes administering to an individual an effective amount of a BChE polypeptide variant, as disclosed herein, to lower blood cocaine concentration

High Activity Mutants of Butyrylcholinesterase for Cocaine Hydrolysis

Butyrylcholinesterase (BChE) polypeptide variants of the presently-disclosed subject matter have enhanced catalytic efficiency for (−)-cocaine, as compared to wild-type BChE. Pharmaceutical compositions of the presently-disclosed subject matter include a BChE polypeptide variant having an enhanced catalytic efficiency for (−)-cocaine. A method of the presently-disclosed subject matter for treating a cocaine-induced condition includes administering to an individual an effective amount of a BChE polypeptide variant, as disclosed herein, to lower blood cocaine concentration

High Activity Mutants of Butyrylcholinesterase for Cocaine Hydrolysis

Butyrylcholinesterase (BChE) polypeptide variants of the presently-disclosed subject matter have enhanced catalytic efficiency for (−)-cocaine, as compared to wild-type BChE. Pharmaceutical compositions of the presently-disclosed subject matter include a BChE polypeptide variant having an enhanced catalytic efficiency for (−)-cocaine. A method of the presently-disclosed subject matter for treating a cocaine-induced condition includes administering to an individual an effective amount of a BChE polypeptide variant, as disclosed herein, to lower blood cocaine concentration

Breakdown voltage of ultrathin dielectric film subject to electrostatic discharge stress

Ultrathin silicon oxide film for nano-electromechanical system (NEMS) applications is investigated under electrostatic discharge (ESD) stress using a transmission line pulse (TLP) tester. The measured breakdown voltage and transient response are analyzed. The results show that the voltage stress time has a significant effect on the breakdown voltage. By shortening the stress time, the breakdown voltage increases by 2–3 times. With the area shrinking breakdown voltage increases, and there is a critical value, below which the breakdown voltage increases dramatically with decreasing area. It is possible to enhance the ESD robustness by using a multiple small-area dielectric layer structure. Shorten ESD pulse rise-time induces a higher overshoot current and then accelerates oxide failure, resulting in a lower breakdown voltage for a faster pulse

An efficient and robust exfoliated bentonite/Ag3PO4/AgBr plasmonic photocatalyst for degradation of parabens

Efficient visible-light-driven heterojunction photocatalysts have attracted broad interest owing to their promising adsorption and degradation performances in the removal of organic pollutants. In this study, a mesoporous exfoliated bentonite (EB)/Ag3PO4/AgBr (30%) photocatalyst was obtained by stripping and exfoliating bentonite as the support for loading Ag3PO4 and AgBr. The particle size ranges of Ag3PO4 and AgBr were about 10-30 nm and 5-10 nm, respectively. The exfoliated bentonite could greatly improve the dispersion and adsorption of Ag3PO4 and AgBr, and significantly enhance the stability of the material during paraben photodegradation. 0.2 g L-1 methylparaben (MPB) was completely decomposed over the EB/Ag3PO4/AgBr (30%) in 40 min under visible light irradiation. In addition, the photocatalytic activity of EB/Ag3PO4/AgBr (30%) remained at about 91% after five recycling runs manifesting that EB/Ag3PO4/AgBr (30%) possessed excellent stability. Radical quenching tests revealed that holes (h+) and hydroxyl radicals (·OH) were the major radicals. They attacked the side chain on the benzene ring of parabens, which were gradually oxidized to the intermediates, such as benzoic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, azelaic acid, and eventually became CO2 and H2O. The enhancement of photocatalytic activity and photo-stability could be ascribed to the stable structural characteristics, enlarged surface area, high absorption ability, and improved light absorption ability from loading Ag3PO4 onto EB. Meanwhile, the matched energy levels of Ag3PO4 and AgBr made the photoelectron-hole pairs separate and transfer effectively at the interfaces. As a result, the photocatalytic properties of EB/Ag3PO4/AgBr (30%) composites were enhanced. © 2020 The Royal Society of Chemistry

Dynamic Optimization of a Polymer Flooding Process Based on Implicit Discrete Maximum Principle

Polymer flooding is one of the most important technologies for enhanced oil recovery (EOR). In this paper, an optimal control model of distributed parameter systems (DPSs) for polymer injection strategies is established, which involves the performance index as maximum of the profit, the governing equations as the fluid flow equations of polymer flooding, and some inequality constraints as polymer concentration and injection amount limitation. The optimal control model is discretized by full implicit finite-difference method. To cope with the discrete optimal control problem (OCP), the necessary conditions for optimality are obtained through application of the calculus of variations and Pontryagin’s discrete maximum principle. A modified gradient method with new adjoint construction is proposed for the computation of optimal injection strategies. The numerical results of an example illustrate the effectiveness of the proposed method