The 5′-untranslated region (5′-UTR) of prokaryotic mRNAs plays an essential role in post-transcriptional regulation. Bacillus species, such as Bacillus subtilis and Bacillus licheniformis, have gained considerable attention as microbial cell factories for the production of various valuable chemicals and industrial proteins. In this work, we developed a portable 5′-UTR sequence for enhanced protein output in the industrial strain B. licheniformis DW2. This sequence contains only ∼30 nt and forms a hairpin structure located right before the open reading frame. The optimized Shine−Dalgarno (SD) sequence was presented as a single strand on the loop of the hairpin for better ribosome recognition and recruitment. By optimizing the free energy of folding, this 5′-element could effectively enhance the expression of eGFP by ∼50-fold and showed good adaptability for other target proteins, including RFP, nattokinase, and keratinase. This 5′-UTR could promote the accessibility of both the SD sequence and start codon, leading to improved efficiency of translation initiation. Furthermore, the hairpin structure protected mRNA against 5′-exonucleases, resulting in enhanced mRNA stability. It is well-known that the stable structure at a ribosome binding site (RBS) impedes initiation in Escherichia coli. In this study, we presented a unique structure at a RBS that can effectively enhance protein production, which is an exception of this prevailing concept. By adjusting a single thermodynamic parameter and holding the other factors affecting protein output constant, a series of 5′-UTR elements with different expression strengths could be rationally designed for wide use in Bacillus sp.

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Purpose The purpose of this paper is to develop an efficient termination control strategy of air-vented dryer in term of energy saving, improving smoothness and reducing microscopic damage of fiber. Design/methodology/approach A simple, low cost termination control strategy is developed by testing the instantaneous humidity of exhaust air and then deducing the drying degree of fabric in process. The practicability evaluation of this novel strategy was investigated by using both experimental and mathematical approaches. The effect of termination control strategy on drying efficiency and fabric apparent properties were also discussed. Findings Termination control strategy significantly affects drying time, energy consumption, smoothness and microscopic of fiber. Specially, a novel termination control strategy that the combination of equilibrium moisture content of fabric in ambient environment and relative humidity of exhaust air in exhaust duct is workable and can save 25.2 percent of energy consumption, 26.7 percent of the drying time and improve 0.7 grade of the appearance smoothness, as well as significantly reduce the microscopic damage of fiber compare to the original control strategy of dryer. This indicates possible ways to minimize drying energy consumption and dryer damage by reducing unnecessary migrate out of the water from the clothes. Practical implications The paper is helpful in not only the development of new drying product but also the optimization of appearance smoothness of fabric after drying and reduce the microscopic damage of fiber. Originality/value A novel termination control strategy of dryer is applied to improve drying efficiency of dryer and reduce fabric damage.

Purpose The purpose of this paper is to prepare composite micro-arc oxide coatings with better wear resistance and corrosion resistance. Design/methodology/approach A nickel powder composite micro-arc oxide film was prepared on the surface of the magnesium alloy by the method of organically combining ultra-fine Ni powder with micro arc oxidation film layer. In this experiment, the changes in the corrosion resistance and microstructure of the composite film layer after adding Ni powder were studied, and the effect of the addition of glycerin on the corrosion resistance of the film layer was analyzed. Findings The results show that the ultra-fine nickel powder was successfully prepared by the liquid phase reduction method, and the micro-arc oxidation process was modified under the optimal addition amount. The surface of the micro-arc oxide film made of ultra-fine nickel powder was found by SEM to have smooth surfaces and few holes. According to X-ray diffraction analysis, the phase composition of the micro-arc oxide film layer was Mg, Ni, NiSiO4, MgNi (SiO4) and Mg2SiO4. According to the results of electrochemical tests, the corrosion resistance of the micro-arc oxidation composite film layer was improved after the addition of ultra-fine Ni powder, the corrosion current was greatly reduced and the impedance has been improved. And after adding glycerin, the surface of the film layer becomes denser, and the corrosion resistance of the micro-arc oxide film is significantly improved. Originality/value Through this experimental research, a micro-arc oxide coating of powder composite magnesium alloy was successfully prepared. The corrosion resistance of the micro-arc oxidation film layer has been improved, and certain functions had been given to the micro-arc oxidation composite film, which has increased the application field of magnesium alloys.