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A variety of myricetin derivatives containing thioether quinoline moiety were designed and synthesized. Their structures of title compounds were determined by 1H NMR, 13C NMR, 19F NMR, and HRMS. Single-crystal X-ray diffraction experiments were carried out with B4. Antiviral activity indicated that some of the target compounds exhibited remarkable anti-tobacco mosaic virus (TMV) activity. In particular, compound B6 possessed significant activity. The half maximal effective concentration (EC50) value of the curative activity of compound B6 was 169.0 μg/mL, which was superior to the control agent ningnanmycin (227.2 μg/mL). Meanwhile, the EC50 value of the protective activity of compound B6 was 86.5 μg/mL, which was better than ningnanmycin (179.2 μg/mL). Microscale thermophoresis (MST) indicated that compound B6 had a strong binding capability to the tobacco mosaic virus coat protein (TMV-CP) with a dissociation constant (Kd) value of 0.013 μmol/L, which was superior to that of myricitrin (61.447 μmol/L) and ningnanmycin (3.215 μmol/L). And the molecular docking studies were consistent with the experimental results. Therefore, these novel myricetin derivatives containing thioether quinoline moiety could become potential alternative templates for novel antiviral agents. [ABSTRACT FROM AUTHOR]

As one of the important natural resources, water resources are related to the future survival and development of human beings. In recent years, the problem of water resources security has become more and more prominent, and it is urgent to study water resources security. Taking 30 provinces and cities in China as an example, this paper constructs a water resources security index system from three aspects of resource supply, social economy and ecological environment, and innovatively proposes a new evaluation method. Specifically, considering the influence of subjective and objective factors on the weighting of indicators, the best–worst method (BWM) and the criteria importance through intercriteria correlation (CRITIC) method are used to determine the subjective and objective weights of each indicator, and the two weights are unified in combination with the principle of maximizing variance. After that, the combined weight was applied to the technique for order preference by similarity to ideal solution (TOPSIS) method, and a new fuzzy multiple criteria decision-making (MCDM) method of combined weighting was finally developed to evaluate the water security status in China. This avoids the error of the traditional single-weight method evaluation to a certain extent, and also conducts other relevant empirical analysis. The research method developed in this paper provides a new idea for dealing with multi-criteria optimization problems in complex systems, and the research results provide a theoretical basis for ensuring regional water resources security and promoting coordinated development among regions. [ABSTRACT FROM AUTHOR]

This research constructs a super efficiency slack-based measure (SBM) model based on the Malmquist-Luenberger (ML) index to analyze the atmospheric environmental efficiency (AEE) of 30 provinces in China from 2000 to 2016 and explores the spatial and temporal differences of AEE by using the coefficient of variation method. This paper further analyzes the internal influencing factors of AEE via the ML index decomposition approach and establishes a panel data regression model to explore AEE's influencing factors in China. The results show some regional differences of the AEE level in China, with it the best in the eastern region and followed in order by the western and central region, and these differences exhibit an increasing trend year by year. During the study period, the development trend of AEE in China is similar to that in the eastern and western regions, showing a "W" shape, where in the central region it has a "U" pattern. The conclusion is that technical progress (TC) is the dominant factor affecting AEE, technical efficiency (EC) fails to effectively promote AEE improvement, and TC and EC present varying degrees of influence and different directions of action in the regions. The analysis results show that the influence effect of economic development on AEE presents a "U" pattern of first declining and then rising. The degree of China opening up to the outside world and its carbon dioxide emissions intensity have significant negative effects on AEE, whereas the increase of pollution control input effectively improves AEE. [ABSTRACT FROM AUTHOR]

In this paper, the roasting and vanadium extraction processes were studied, and the relevant theory was analyzed. Experimental results indicated that the ratio of additives, the roasting time, and the oxidizing atmosphere all had a significant influence on the extraction rate of vanadium from vanadium slag with a high silicon content. The extraction rate of vanadium reached as high as 84.45% under the optimized experimental conditions: a roasting temperature of 1123 K, a roasting time of 4 h, 13% (mass fraction) of the additive Na2CO3 in the raw material, and an atmosphere volume fraction in excess of 25%(excess oxygen of 5.25%). The results of this study can provide a guide for industrial production, and have a certain application value. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the suitability of using nanopaper as an insulating material since it has outstanding mechanical and thermal properties. Nanopaper consisting of nanofibrillated cellulose was prepared. Properties of ordinary insulating paper were taken as a reference. DC volume resistivity results show that nanopaper can obtain a relatively high value of 2.55 × 1012 Ω m, which will be more compatible with mineral oil. In spite of the lower density, nanopaper tends to have a higher complex relative permittivity than reference paper. Due to the decreased pore size, nanopaper presents a remarkably enhanced DC breakdown strength. The dielectric strength of nanopaper can reach 69.4 kV/mm, whereas that of ordinary kraft paper is only 20.4 kV/mm. It is concluded that nanopaper has good electrical properties. The decreased volume resistivity and dramatically enhanced breakdown strength indicate that the potential application of nanopaper in convert transformers is promising. [ABSTRACT FROM AUTHOR]

There is a growing enthusiasm to combine the data envelopment analysis (DEA) method with the conception of “big data.” This study proposes a new algorithm to deal with massive data for DEA with undesirable output. First, we modified the current weak disposability model to deal with undesirable output and prove its applicability. Then, we introduced the two fastest approaches (build hull approach and pre-score approach) and found that they cannot be directly employed in DEA with undesirable output because the pre-score approach may not be as powerful. We modified these two approaches to make them capable of dealing with undesirable output and integrated them by proposing a new algorithm. In practice, we used simulated data and data of Chinese industrial enterprises including environmental and health indicators, and all the above data meet the requirements of the model. The results show that our approach can not only be applied to deal with undesirable output in DEA, but it also can perform better than the build hull approach in some situations. Our approach also benefits the pre-score approach if it cannot include total efficiency units. Finally, five datasets were collected or generated to test the capability of our approach. [ABSTRACT FROM AUTHOR]

Loblolly pine ( Pinus taeda L.) is the mostimportant tree species in US commerce and has much to gain through geneticengineering. This species can be transformed using particle bombardment and Agrobacterium; however, the regeneration of plants fromtransgenic tissues has been difficult and the recovery of transgenic plants hasbeen rare. A shoot-based and genotype-independent transformation methodemploying Agrobacterium tumefaciens was used to facilitaterecovery of plants and permit the transformation of elite germplasm. Shootsfrom4–6 week old seedlings and adventitious shoots from culture wereinoculated with A. tumefaciens EHA101 (pGUS3), or EHA105(pSSLa.3), subjected to selection and regenerated. Shoots that survivedexhibited expression of the uidA gene (GUS) in a patterncharacteristic of the either the CaMV35S promoter (pGUS3), or the larch RbcSpromoter (pSSLa.3) transferred. Recovered plants were screened using PCRamplification. Southern DNA analyses and amplification of the T-DNA borderjunction confirmed genomic integration of both transferred uidA and nptII genes. In this proofofconcept study, the overall recovery of P. taeda shoots wasfair (10–20%), while recovery of intact rooted plants was poor (>1%)due to difficulty in rooting. Recovery of intact rooted plants from inoculatedshoots of P. eldarica and P. radiatawas more efficient (10–30%). The addition of a shoot multiplication stepand effective rooting protocols will improve the efficiency of this genotypeindependent transformation method in P. taeda, and inother Pinus spp. [ABSTRACT FROM AUTHOR]

Presents a study on a method to identify junction sequences in plants transformed using Agrobacterium tumefaciens using transformed tobacco plants. Materials and methods utilized in the study; Procedures on the digestion of genomic deoxyribosenucleic acid (DNA) from transformed tobacco plants; Information on electrophoresis and band purification.

DNA methylation has been associated with gene activity in differentiating and developing plant tissues. The objective of this study was to determine the involvement of methylation in the expression of a gene transferred into carrot ( Daucus carota L.) tissues by particle bombardment. Expression of the Dc8-GUS gene construct in response to treatments with 5-azacytidine (S-azaC) and to in vitro methylation by methylases was investigated by histochemical assay of GUS activity. The 5-azaC treatment increased the frequency of Dc8-driven GUS expression in both calli and somatic embryos. The increase occurred with treatment either to E. coli containing the plasmid insert or to the carrot tissues before bombardment. GUS expression, increased by the 5-azaC treatment, was enhanced by ABA treatment of both calli and somatic embryos and was more prominent in the latter. Increased digestion of the 5-azaC-treated plasmid DNA with EcoRII suggested that demethylation had occurred. In vitro methylation of Dc8-GUS by methylases generally resulted in a lower frequency of GUS expression. SssI methylase completely inhibited GUS expression. The level of GUS expression was correlated with the extent of methylation of the plasmid. [ABSTRACT FROM AUTHOR]