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In recent years, hepatitis B virus (HBV) core protein allosteric modulators (CpAMs) have become a hot spot to develop new anti‐HBV drugs. Sulfonamide analogues are a new class of CpAMs targeting HBV core protein (Cp), while their biological activity is still needed to be improved and the binding mechanism is unclear still. In this study, we utilized molecular docking and molecular dynamics simulation to explore the binding mode between the novel compounds and HBV Cp. Combining with binding free energy calculation and decomposition, we inferred that TyrE132, ValE124, ThrE128, ThrD109, and IleD105 were key residues during the binding process, and especially, the conformational change of TryE132 was responsible for the stable binding. Besides, reasonable CoMFA (q2 = 0.515, r2ncv = 0.994, and r2pred = 0.628) and CoMSIA (q2 = 0.602, r2ncv = 0.988, and r2pred = 0.681) models were constructed to explore the 3D structure‐activity relationship of the novel compounds. The results suggested that it was favorable to increase the biological activity of sulfonamide analogues when introducing hydrophobic groups to R1 and electronegative groups to R2. In conclusion, we explored the binding mode and structure‐activity relationship between sulfonamides and HBV Cp and provided a theoretical basis for the optimization of this series of compounds. [ABSTRACT FROM AUTHOR]

This study investigates the impacts of the joint assimilation of ground-based microwave radiometer (MWR) and FY-3D microwave sounder (MWTS-2/MWHS-2) observations on the analyses and forecasts for precipitation forecast. Based on the weather research and forecasting data assimilation (WRFDA) system, four experiments are conducted in this study, concerning a heavy precipitation event in Beijing on 2 July 2021, and 10-day batch experiments were also conducted. The key study findings include the following: (1) Both ground-based microwave radiometer and MWTS-2/MWHS-2 data contribute to improvements in the initial fields of the model, leading to appropriate adjustments in the thermal structure of the model. (2) The forecast fields of the experiments assimilating ground-based microwave radiometer and MWTS-2/MWHS-2 data show temperature and humidity performances closer to the true fields compared with the control experiment. (3) Separate assimilation of two types of microwave radiometer data can improve precipitation forecasts, while joint assimilation provides the most accurate forecasts among all the experiments. In the single-case, compared with the control experiment, the individual and combined assimilation of MWR and MWTS-2/MWHS-2 improves the six-hour cumulative precipitation threat score (TS) at the 25 mm level by 57.1%, 28.9%, and 38.2%, respectively. The combined assimilation also improves the scores at the 50 mm level by 54.4%, whereas individual assimilations show a decrease in performance. In the batch experiments, the MWR_FY experiment's TS of 24 h precipitation forecast improves 28.5% at 10 mm and 330% at 25 mm based on the CTRL. [ABSTRACT FROM AUTHOR]

Practical Application Edible mushrooms are rich in nutrients and bioactive compounds, but their browning affects their quality and commercial value. This article reviews various methods to inhibit polyphenol oxidase (PPO)‐induced browning in mushrooms. Physical methods such as heat treatment, low temperatures, irradiation, and ultrasound effectively reduce PPO activity but may affect mushroom texture and flavor. Chemical inhibitors, including synthetic chemicals and natural plant extracts, provide effective PPO inhibition but require careful monitoring of their content. Biological methods, including gene editing and microbial fermentation, show promise in targeting PPO genes and enhancing antioxidant production. Combining these methods offers a comprehensive strategy for preserving mushroom quality, extending shelf life, and maintaining nutritional value.These approaches can be applied in the food industry to improve post‐harvest mushroom preservation, enhance product quality, and reduce waste, benefiting both producers and consumers. Further research and innovation are needed to optimize the practical application of these methods in large‐scale processing and storage conditions. [ABSTRACT FROM AUTHOR]

With the development of wireless mobile network and Internet of Things (IoT), users enter the network with a large amount of data and information, including some important personal information, such as ID number, telephone number. Personal privacy disclosure has become one of the focuses of attention. In this article, we propose an asymmetric group key agreement (GKA) protocol based on attribute threshold for IoT to protect user privacy. Users do not need to expose any personal information in the group, but only need to meet the same number of attributes and conduct bidirectional authentication registration with key generation center (KGC) to ensure the legitimacy of mobile terminal members participating in GKA. In the registration phase, user performs heavy preliminary calculations according to the designed protocol, thereby reducing the computation in the key agreement phase and decreasing the complexity of the protocol. The protocol can realize self‐verification, and any member participating in key agreement can verify the correctness of the negotiated key by themselves. Under the assumption of bilinear computational Diffie‐Hellman problem, the security of the protocol is proved. Performance analysis further shows that our protocol has lower energy consumption in terms of communication and computing. [ABSTRACT FROM AUTHOR]

Dual-level electronic structure calculation has been performed to investigate the mechanism and all possible channels of OH radical reaction with CH3CH2F. Geometries and frequencies are computed at the B3LYP/6-311G(d, p) level of theory for all stationary points and complexes and transition states are located. Potential energy surfaces are constructed at the PMP2/cc-pVTZ//B3LYP/6311G(d,p) level + ZPE correction. Four types of reaction channels are identified: hydrogen abstraction, fluorine abstraction and attack on carbon atom along or perpendicular to the C - C bond axis. Hydrogen abstraction channels have lower barriers and are more exothermic, while out-of-plane β - H abstraction with the lowest barrier is competitive with α - H abstraction. Due to the high energy barrier, contributions of non-H abstraction channels are excluded. The influence of hydrogen bonding interaction is clearly observed in the barrier heights. [ABSTRACT FROM AUTHOR]

We examined Chinese stonefly specimens of the Rhopalopsolevietnamica 'western assemblage' group. A new species from Hainan Province, R.bawanglinga Li, Li & Yang, sp. nov. is described and illustrated from male and female adults, and it is compared to closely related taxa. The hitherto unknown female of R.hainana Li & Yang, 2010 is described. Morphological evidence is presented for the identity of R.dentiloba Wu, 1973, on the basis of topotypes from Yunnan Province, southwestern China., Competing Interests: The authors have declared that no competing interests exist.

Two poorly known species of Kamimuria Klaplek, 1907 originally known from southern China, K. melli Wu, 1935 and K. taoi Wu, 1936, are rediscovered and amended with supplementary descriptions of the aedeagi. Kamimuria atra Sivec & Stark, 2008 is recorded for the first time from China. Kamimuria liui (Wu, 1940) is newly recorded from southern China, amended with descriptions of the aedeagus and noted morphological variability, and compared to related congeners. Digital micrographs of the adult male, including the fully extruded aedeagi, are presented for the first time for the above four species.