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The quantum supremacy experiment, such as Google Sycamore [F. Arute et al., Nature (London) 574, 505 (2019).NATUAS0028-083610.1038/s41586-019-1666-5], poses a great challenge for classical verification due to the exponentially increasing compute cost. Using a new-generation Sunway supercomputer within 8.5 d, we provide a direct verification by computing 3×10^{6} exact amplitudes for the experimentally generated bitstrings, obtaining a cross-entropy benchmarking fidelity of 0.191% (the estimated value is 0.224%). The leap of simulation capability is built on a multiple-amplitude tensor network contraction algorithm which systematically exploits the "classical advantage" (the inherent "store-and-compute" operation mode of von Neumann machines) of current supercomputers, and a fused tensor network contraction algorithm which drastically increases the compute efficiency on heterogeneous architectures. Our method has a far-reaching impact in solving quantum many-body problems, statistical problems, as well as combinatorial optimization problems.

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In order to investigate the flavour characteristics of aromatic, glutinous, and nonaromatic rice, gas chromatography-ion mobility spectrometry (GC-IMS) was used to analyse the differences in volatile organic compounds (VOCs) amongst different rice varieties. The results showed that 103 signal peaks were detected in these rice varieties, and 91 volatile flavour substances were identified. Amongst them, 28 aldehydes (28.89~31.17%), 24 alcohols (34.85~40.52%), 14 ketones (12.26~14.74%), 12 esters (2.30~4.15%), 5 acids (7.80~10.85%), 3 furans (0.30~0.68%), 3 terpenes (0.34~0.64%), and 2 species of ethers (0.80~1.78%) were detected. SIMCA14.1 was used to perform principal component analysis (PCA) and orthogonal partial least squares discriminant analysis, and some potential character markers (VIP > 1) were further screened out of the 91 flavour substances identified based on the variable important projections, including ethanol, 1-hexanol, hexanal, heptanal, nonanal, (E)-2-heptenal, octanal, trans-2-octenal, pentanal, acetone, 6-methyl-5-hepten-2-one, ethyl acetate, propyl acetate, acetic acid, and dimethyl sulphide. Based on the established fingerprint information, combined with principal component analysis and orthogonal partial least squares discriminant analysis, different rice varieties were also effectively classified, and the results of this study provide data references for the improvement in aromatic rice varieties.

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Phase transformation between metal halide perovskites serves as a promising route to create new optoelectronic functionalities. Nevertheless, the transformation reported thus far mainly involves the transition between two individual phases (e.g., 0D-3D and 3D-2D), while the transition from one phase to a heterostructure with distinct phases has been rarely disclosed. Here, we report a straightforward one-step procedure to directly convert 0D perovskite to 2D/3D heterostructures and demonstrate the application of the derivatives in random lasing beyond 0D perovskite. This phase transformation was triggered by exposing the 0D perovskite to a water environment and the resultant 2D/3D heterostructure showed much improved water resistance compared to that of its corresponding 3D counterpart as for chemical stability and photoluminescence performance. In addition, we demonstrated that the derived 2D/3D heterostructure readily exhibited random lasing characteristic of incoherent feedback upon optical pumping, while the parent 0D Cs4PbBr6 exhibited no sign of light amplification even pumped much harder. The pump threshold and the PL spectral profile were well maintained upon recycling treatment with water, implying the water resistance capability of the developed random lasing. The results suggest that the 2D/3D perovskite composites derived from the phase transformation of their 0D counterpart can serve as promising platforms for nanophotonic applications.

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This study was aimed to assess the potential of Dioscorea (yam) leaves as a source of antioxidants. Microwave-assisted extraction (MAE) process was used to prepare the extracts. The phenolic compounds in Dioscorea leaves extracts were analyzed by HPLC-DAD-ESI-MS/MS method and the contents of major compounds were determined. Results indicated that a total of 17 phenolic compounds were separated identified by means of UV and mass spectra compared with authentic reference substances and/or reported values in the literature. The main phenolic compound was rosmarinic acid and its highest amount was found in Dioscorea glabra Roxb. leaves (22.31±1.33 mg/g DW). Rutin was the dominant flavonoid followed by quercetin which highest amount was found in Dioscorea alata leaves (8.66±0.29 mg/g DW). Antioxidant activity of the extracts was estimated by the use of DPPH and ABTS assays. Both kinds of leaves exhibited satisfied antioxidant capacity which was correlated with phenolic contents. In the cytoprotective effect on HUVECs viability assay, Dioscorea glabra Roxb. leaves extract was found to be more active than that of Dioscorea alata against H2O2-induced oxidative stress. Our findings support the promising role of Dioscorea leaves that can be used as an interesting source of phenolic antioxidants.

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Abstract: In this study, same amount of potassium (240 kg . hm-2) was applied as basal dressing (treatment 1) and as 1/2 basal dressing + 1/2 top-dressing at day 75 after planting (treatment 2), aimed to investigate the effects of potassium fertilization period on the photosynthetic characteristics of edible sweetpotato and the starch accumulation in storage root. As compared with treatment 1, treatment 2 improved the leaf photosynthetic rate and sucrose-phosphate synthase activity and the storage root's adenosine diphosphate glucose pyrophosphortlase activity, enhanced the starch accumulation rate in storage root (with an average increment of 6. 7%), and increased the root tuber yield significantly by 8. 2%. Both of the potassium fertilization treatments improved the synthesis of sucrose in leaf and the transformation from sucrose to starch in storage root, as compared with no potassium fertilization.

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Aiming at the present tedious English translation of traditional Chinese medicine, the author advocates some approaches to simplify it in order to improve the readability, communicability and quality of translation.

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