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The study of a flexible body immersed in a flowing medium is one of best way to find its aerodynamic shape. This Letter revisited the problem first studied by Alben, Shelley and Zhang (Nature 420, 479-481, 2002). The aerodynamic shape of the fibre is found by simpler approach and universal drag scaling laws of the flexible fibre in flowing medium are proposed by using dimensional analysis. The Alben scaling laws is being generalized and confirmed to be universal. Our study show that the Alben number is a measurement of maximum curvature of the fibre forced by dynamic pressure. A complete Maple code is provided for finding aerodynamic shape of the fibre in the flowing medium.

The common dandelion uses a bundle of drag-enhancing bristles (the pappus) that enables seed dispersal over formidable distances; however, the scaling laws of pneumatic/aerodynamic drag underpinning pappus-mediated flight remains unresolved. In this paper, we will study the pneumatic/aerodynamic shape of dandelion and the scaling law of resistance, and find that the drag resistance coefficient is proportional to the -2/3 power of the dandelion pappus Reynolds number. As a by-product, the terminal velocity analytical expression of the dandelion seed is also obtained.

A new fault diagnosis method of rolling bearings was presented based on variational mode decomposition (VMD), Tsallis entropy and Fuzzy C-means clustering (FCM) algorithm. Firstly, the measured vibration signals were decomposed with VMD in different scales to obtain a series of band-limited intrinsic modal function (BIMF). The VMD parameters were determined according to the change of the BIMF center frequency. Then, the Tsallis entropy of BIMF components were calculated and used as the signal features. Finally, the features were put into FCM classifier to recognize different fault types. It is proved by experiments that this method is feasible and the proposed approach could obtain better result compared with the method based on mode decomposition (EMD) and local mean decomposition (LMD).

[Image: see text] Covalent modification of disease-associated proteins with small molecules is a powerful approach for achieving an increased and sustained pharmacological effect. To reduce the potential risk of nonselective covalent modification, molecular design of covalent inhibitors is critically important. We report herein the development of a targeted covalent inhibitor for mutated epidermal growth factor receptor (EGFR) (L858R/T790M) using α-chlorofluoroacetamide (CFA) as the reactive group. The chemically tuned weak reactivity of CFA was suitable for the design of third-generation EGFR inhibitors that possess the pyrimidine scaffold. The structure–activity relationship study revealed that CFA inhibitor 18 (NSP-037) possessed higher inhibition selectivity to the mutated EGFR over wild-type EGFR when compared to clinically approved osimertinib. Mass-based chemical proteomics analyses further revealed that 18 displayed high covalent modification selectivity for the mutated EGFR in living cells. These findings highlight the utility of CFA as a warhead of targeted covalent inhibitors and the potential application of the CFA-pyrimidines for treatment of non-small-cell lung cancer.

The nanocrystallization behaviour of a bulk Zr-based metallic glass subjected to compressive stress is investigated in the supercooled liquid region. Compared with annealing treatments without compressive stress, compressive deformation promotes the development of nucleation and suppresses the coarsening of nanocrystallites at high temperatures.