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Comprehensive dynamical simulations of a prototypical multi-channel reaction on a globally accurate potential energy surface show that the non-statistical product branching is dictated by unique stereodynamics in the entrance channels., Hydrogen abstraction from methanol (CH3OH) by F atoms presents an ideal proving ground to investigate dynamics of multi-channel reactions, because two types of hydrogen can be abstracted from the methanol molecule leading to the HF + CH3O and HF + CH2OH products. Using the quasi-classical trajectory approach on a globally accurate potential energy surface based on high-level ab initio calculations, this work reports a comprehensive dynamical investigation of this multi-channel reaction, yielding measurable attributes including integral and differential cross sections, as well as branching ratios. It is shown that while complex-forming and direct mechanisms coexist at low collision energies, these barrierless reaction channels are dominated at high energies by the direct mechanism, in which the reaction is only possible for trajectories entering into the respective dynamical cones of acceptance. Perhaps more importantly, the non-statistical product branching is found to be dictated by unique stereodynamics in the entrance channels.

otrA resembles elongation factor G (EF-G) and is considered to be an oxytetracycline (OTC)-resistance determinant in Streptomyces rimosus. In order to determine whether otrA also conferred resistance to OTC and other aminoglycosides to Streptomyces coelicolor, the otrA gene from S. rimosus M527 was cloned under the control of the strong ermE * promoter. The resulting plasmid, pIB139-otrA, was introduced into S. coelicolor M145 by intergeneric conjugation, yielding the recombinant strain S. coelicolor M145-OA. As expected S. coelicolor M145-OA exhibited higher resistance levels specifically to OTC and aminoglycosides gentamycin, hygromycin, streptomycin, and spectinomycin. However, unexpectedly, S. coelicolor M145-OA on solid medium showed an accelerated aerial mycelia formation, a precocious sporulation, and an enhanced actinorhodin (Act) production. Upon growth in 5-L fermentor, the amount of intra-and extracellular Act production was 6-fold and 2-fold higher, respectively, than that of the original strain. Consistently, reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that the transcriptional level of pathway-specific regulatory gene actII-orf4 was significantly enhanced in S. coelicolor M145-OA compared with in S. coelicolor M145.

In recent years, the automotive industry has faced an unprecedented crisis. In particular, the zero-inventory approach, which has been widely pursued by many automobile companies, seems to be impractical in some real production contexts since it requires an inventory of all parts but in low amounts. In this paper, we investigate a new logistics method which collects automobile parts by integrating the progress-lane (P-LANE) into the corresponding vehicle routing problem. We propose a mixed integer programming formulation for this new model, which can simultaneously determines the trip routes to collect automobile parts, as well as the P-LANE that each collected part should be assigned to, so as to minimize the total costs of the production and inbound logistics. The comparison with the zero-inventory model shows that the use of the P-LANE within the milk-run system could significantly decrease the total costs and also improve the transportation efficiency. To be specific, for small and large size instances, the total costs of the zero-inventory model are about 10% and 30% higher than the ones with P-LANE, respectively, which suggests that the periodic part collection model with P-LANE could be more appropriate for automobile manufacturing.

Given the problems in traditional graphite purification methods, such as low impurity removal efficiency; Using chemical purification method, the reagent is toxic and contaminated, which does not meet the environmental protection requirements; The physical purification method has the disadvantages of high energy consumption and high cost. The plasma spraying graphite purification method is proposed and its mechanism is studied. A prototype of the plasma spraying graphite purification device was assembled and developed. With the built purification device prototype as the research object, the state monitoring and comprehensive evaluation of the working gas flow, system working current, working voltage, carbon powder quantity, and other indicators are carried out. The change of impurity content in graphite was analyzed by the plasma spraying method under different index conditions. Experiments show that the graphite can be effectively purified by plasma spraying graphite purification method, and the carbon content is increased from 94.18% to 97.23%.

Actinomycetes have received considerable attention as biocontrol agents against fungal plant pathogens and as plant growth promoters. In this study, a total of 320 actinomycetes were isolated from various habitats in China. Among which, 77 strains have been identified as antagonistic activities against Fusarium oxysporum f. sp. cucumerinum which usually caused fusarium wilt of cucumber. Of these, isolate actinomycete M527 not only displayed broad-spectrum antifungal activity but also showed the strongest antagonistic activity against the spore germination of F. oxysporum f. sp. cucumerinum. In pot experiments, the results indicated that isolate M527 could promote the shoot growth and prevent the development of the disease on cucumber caused by F. oxysporum f. sp. cucumerinum. The control efficacy against seedling fusarium wilt of cucumber after M527 fermentation broth root-irrigation was up to 72.1% as compared to control. Based on 16S rDNA sequence analysis, the isolate M527 was identified as Streptomyces rimosus.

A novel 2&prime, F,4&prime, C-OMe&ndash, arabinouridine (araU) was successfully synthesized and introduced into oligonucleotides. The oligonucleotide containing 2&prime, araU exhibited improved nuclease resistance and RNA hybridizing selective ability relative to 2&prime, F&ndash, araU. In particular, when 2&prime, araU inserted into C&ndash, H⋯F&ndash, C bonding-favorable 5&prime, &ndash, uridine&ndash, purine&ndash, 3&prime, steps, the modified oligonucleotide showed remarkable binding affinity and selectivity to RNA complements. Thus, 2&prime, araU has valuable antisense properties and can be used as novel chemical modification for antisense therapeutic strategy.

Blackleg and sclerotinia stem rot caused by Leptosphaeria maculans and Sclerotinia sclerotiorum respectively are two major diseases in rapeseed worldwide, which cause serious yield losses. Chitinases are pathogenesis-related proteins and play important roles in host resistance to various pathogens and abiotic stress responses. However, a systematic investigation of the chitinase gene family and its expression profile against L. maculans and S. sclerotiorum infection in rapeseed remains elusive. The recent release of assembled genome sequence of rapeseed allowed us to perform a genome-wide identification of the chitinase gene family. In this study, 68 chitinase genes were identified in Brassica napus genome. These genes were divided into five different classes and distributed among 15 chromosomes. Evolutionary analysis indicated that the expansion of the chitinase gene family was mainly attributed to segmental and tandem duplication. Moreover, the expression profiling of the chitinase gene family was investigated using RNA sequencing (RNA-Seq) and the results revealed that some chitinase genes were both induced while the other members exhibit distinct expression in response to L. maculans and S. sclerotiorum infection. This study presents a comprehensive survey of the chitinase gene family in B. napus and provides valuable information for further understanding the functions of the chitinase gene family.