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Adhesive hydrogels, playing an essential role in stretchable electronics, soft robotics, tissue engineering, and so forth, upon functioning often need to adhere to various substrates in wet conditions and simultaneously exhibit antibacterial/antioxidant properties while possessing the intrinsic stretchability and elasticity of the hydrogel network intact. Therefore, simple approaches to conveniently access adhesive hydrogels with multifunctional surfaces are being pursued. Herein, a facile strategy has been proposed to construct multifunctional adhesive hydrogels via surface engineering of a multifunctional carbon dot (CD)-decorated polymeric thin layer by dynamic bond exchange. By this strategy, a double cross-linked network hydrogel of polyacrylamide (PAM) and oxidized dextran (ODA) was engineered with a unique dense layer over the Schiff base hydrogel matrix by aqueous solution immersion of PA-120, versatile CDs derived from tannic acid (TA) and ε-polylysine (PL). Without any additional agents, the PA-120 CDs with residual polyphenolic/catechol and amine moieties were incorporated into the surface structure of the hydrogel network by the combined action of the Schiff base and hydrogen bonds to form a dense surface layer that can exhibit high wet adhesive performance via the amine–polyphenol/catechol pair. The armor-like dense architecture also endowed hydrogels with considerably enhanced tensile/compression properties and excellent antioxidant/antibacterial abilities. Besides, the single-sided modified Janus hydrogel and completely surface-modified hydrogel can be flexibly developed through this approach. This strategy will provide new insights into the preparation and application of surface-modified hydrogels featuring multiple functions and tunable interfacial properties.

Purpose: The purpose of this paper is to examine the factors that influence Chinese consumers’ purchase of organic products, with a focus on organic tea. Design/methodology/approach: A structured questionnaire was used to survey 202 shoppers in Guangdong Province, China. The data were analyzed using multivariate regression. Findings: The study suggests two significant predictors of organic tea purchase intentions: perceiving organic tea as a healthier alternative to non-organic tea; perceiving the purchase of organic tea as a status symbol. Younger respondents and respondents with higher educational attainment reported greater organic tea purchase intentions. Non-significant predictors of organic tea purchase intentions were respondents’ knowledge of organic tea through media exposure, their gender and income. Research limitations/implications: The findings help further research on consumer preferences regarding organic foods providing key insights for researchers and marketers as they strive to make informed decisions in the emerging organic food retail environment. Specifically, Chinese consumers perceiving organic tea as a healthy option and as a status symbol are more likely to state organic tea purchase intentions. These results point to the need for extended research on key antecedents of Chinese consumers’ purchase intentions of organic products. Originality/value: Little was known about the motivations of Chinese consumers for purchasing organic food products, as the psychological and demographic factors that are associated with organic food purchase behavior in China were not well researched. Specifically, there is still a notable gap in the understanding of how consumers in China make organic tea purchase decisions. With organic foods occupying a progressively larger portion of Chinese diets and budgets, this research fills in some of the knowledge gap by examining how the social norms of status symbols influence Chinese consumers’ purchase intentions of organic tea.

A highly regio-specific and donor-promiscuous 3-O-glycosyltransferase, Sb3GT1 (UGT78B4), was discovered from Scutellaria baicalensis. Sb3GT1 could accept five sugar donors (UDP-Glc/-Gal/-GlcNAc/-Xyl/-Ara) to catalyze 3-O-glycosylation of 17 flavonols, and the conversion rates could be >98%. Five new glycosides were obtained by scaled-up enzymatic catalysis. Molecular modeling and site-directed mutagenesis revealed that G15 and P187 were critical catalytic residues for the donor promiscuity. Sb3GT1 could be a promising catalyst to increase structural diversity of flavonoid 3-O-glycosides.

In this multicenter study, we compared the performance of the Bruker Biotyper MS system and VITEK 2 YST systems for invasive yeast identification, investigated the distribution of isolated species, and evaluated the antifungal susceptibility profiles of Candida albicans, Candida parapsilosis, and Candida tropicalis. In cases of discrepant results lack of identification with either method, molecular identification techniques were employed. We tested 216 clinical isolates, and concordance between the two methods was observed for 192/216 isolates (88.9%). For five unidentified strains (2.3%), an internal transcribed spacer (ITS) sequencing approach was used. In brief, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF MS) provided short turnaround times and more reliable results than those of Vitek 2 YST. In Wuhan, C. albicans, C. parapsilosis, Candida glabrata, and C. tropicaliswere the most common pathogens (93.0%) in patients with candidemia. Cryptococcus neoformanswas mainly detected in cerebrospinal fluid samples (88.9%). Trichosporon asahiiwere all isolated from drainage fluids in the Surgery. Candida albicanswas clearly susceptible to azoles, while C. parapsilosisand C. tropicalisdisplayed differences in susceptibility to azoles. Our findings provide a basis for the practical application of MALDI-ToF MS for identification and for the use of ATB FUNGUS 3 to characterize the susceptibility of Candidaspp., thereby providing significant data for therapeutic decisions.

This paper develops a mathematical model to quantify the market share of given freight transport corridor. By analysing the whole process of door to door freight transport, the generalized cost model of railway and highway is established, respectively. A case study of long-distance transport in China's inland cities is subsequently conducted to explore market share of railway and highway. At last, the sensitivity of influence factors is analysed. We find that the average train speed, waiting time to be loaded, container volume and transport distance can significant affect the railway market share. The railway market share increases as the average train speed, container volume and transport distance increase, while decreases as the time waiting to be loaded increases. When the average trains speed is over 50km/h, or the time waiting to be loaded is less than 1.5 d, railway market share is over 50%. Moreover, railway is more competitive in high capacity and long-distance freight transport. We also find that the result of single factor's change is limit, while the change of multi-factors can affect the railway market share greatly.

O-methyltransferases play essential roles in producing structural diversity and improving the biological properties of benzylisoquinoline alkaloids (BIAs) in plants. In this study, Corydalis yanhusuo, a plant used in traditional Chinese medicine due to the analgesic effects of its BIA-active compounds, was employed to analyze the catalytic characteristics of O-methyltransferases in the formation of BIA diversity. Seven genes encoding O-methyltransferases were cloned, and functionally characterized using seven potential BIA substrates. Specifically, an O-methyltransferase (CyOMT2) with highly efficient catalytic activity of both 4′- and 6-O-methylations of 1-BIAs was found. CyOMT6 was found to perform two sequential methylations at both 9- and 2-positions of the essential intermediate of tetrahydroprotoberberines, (S)-scoulerine. Two O-methyltransferases (CyOMT5 and CyOMT7) with wide substrate promiscuity were found, with the 2-position of tetrahydroprotoberberines as the preferential catalytic site for CyOMT5 (named scoulerine 2-O-methyltransferase) and the 6-position of 1-BIAs as the preferential site for CyOMT7. In addition, results of integrated phylogenetic molecular docking analysis and site-directed mutation suggested that residues at sites 172, 306, 313, and 314 in CyOMT5 are important for enzyme promiscuity related to O-methylations at the 6- and 7-positions of isoquinoline. Cys at site 253 in CyOMT2 was proved to promote the methylation activity of the 6-position and to expand substrate scopes. This work provides insight into O-methyltransferases in producing BIA diversity in C. yanhusuoand genetic elements for producing BIAs by metabolic engineering and synthetic biology.