The extension of microfluidic devices to include three-dimensional fluidic networks allows complex fluidic and chemical manipulations but requires innovative methods to interface fluidic layers. Externally controllable interconnects, employing nuclear track-etched polycarbonate membranes containing nanometer-diameter capillaries, are described that produce hybrid three-dimensional fluidic architectures. Controllable nanofluidic transfer is achieved by controlling applied bias, polarity, and density of the immobile nanopore surface charge and the impedance of the nanocapillary array relative to the microfluidic channels. Analyte transport between vertically separated microchannels has three stable transfer levels, corresponding to zero, reverse, and forward bias. The transfer can even depend on the properties of the analyte being transferred such as the molecular size, illustrating the flexible character of the analyte transfer. In a specific analysis implementation, nanochannel array gating is applied to capillary electrophoresis separations, allowing selected separated components to be isolated for further manipulation, thereby opening the way for preparative separations at attomole analyte mass levels.

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The aim of this study was to investigate how the effects of compound probiotics modulate the gut microbiota, short-chain fatty acid (SCFA), body composition, serum and liver lipids, and inflammatory markers in non-alcoholic fatty liver disease (NAFLD) rats. Twenty-four male SD rats were randomly divided into 3 groups: normal control group (standard feed), high-fat diet (HFD) feeding group (83% standard feed + 10% lard oil + 1.5% cholesterol + 0.5% cholate + 5% sucrose), and compound probiotics intervention group (HFD + 0.6 g × kg × d compound probiotics). The microbial population was assessed by 16S rDNA amplification and sequence analysis. Body composition, serum and liver lipids, serum inflammatory markers, colonic SCFAs, and relative proteins were assessed. The results showed that compound probiotics significantly reduced body weight, visceral and total fat mass, and the levels of hepatic TC and TG and serum TG, FFA, ALT, LPS, IL-1β, and IL-18 (P < 0.05). The proportions of TM7 phylum (0.06 vs 1.57%, P < 0.05) clearly increased, while that of Verrucomicrobia phylum (5.69 vs 2.61%, P < 0.05) clearly decreased. Compound probiotics also increased the representation of Ruminococcus genus (0.95 vs 1.83%, P < 0.05), while the proportion of Veillonella genus decreased (0.10 vs 0.03%, P < 0.05). The levels of colonic SCFAs and GPR43, NLRP3, ASC, and CASPASE-1 proteins also changed significantly (P < 0.05). Compound probiotics modulated gut microbiota, SCFAs, and their receptor GPR43 in NAFLD rats. These changes might inhibit lipid deposition and chronic metabolic inflammation in response to the insult of HFD.

The development of a new method for glycosylation with 1-hydroxy glycosyl donors employing dialkyl sulfonium reagents is described. The process employs the reagent combination of a dialkyl sulfide and triflic anhydride to effect anomeric bond constructions. This controlled dehydrative coupling of various C(1)-hemiacetal glycosyl donors and nucleophilic acceptors proceeds by way of a sulfide-to-sulfoxide oxidation process in which triflic anhydride serves as the oxidant.

Despite the large reduction in anthropogenic activities due to the outbreak of COVID-19, air quality in China has witnessed little improvement and featured great regional disparities. Here, by combining observational data and simulations, this work aims to understand the diverse air quality response in two city clusters, Yangtze River Delta region (YRD) and Pearl River Delta region (PRD), China. Though there was a noticeable drop in primary pollutants in both the regions, differently, the maximum daily 8 h average ozone (O 3 ) soared by 20.6–76.8% in YRD but decreased by 15.5–28.1% in PRD. In YRD, nitrogen oxide (NOx) reductions enhanced O 3 accumulation and hence increased secondary aerosol formation. Such an increment in secondary organic and inorganic aerosols under stationary weather reached up to 36.4 and 10.2%, respectively, which was further intensified by regional transport. PRD was quite the opposite. The emission reductions benefited PRD air quality, while regional transport corresponded to an increase of 17.3 and 9.3% in secondary organic and inorganic aerosols, respectively. Apart from meteorology, the discrepancy in O 3 –VOCs–NOx relationships determined the different O 3 responses, indicating that future emission control shall be regionally specific, instead of one-size-fits-all cut. Overall, the importance of regionally coordinated and balanced control strategy for multiple pollutants is highly emphasized.