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Describes the design of reliable systems using static and dynamic fault trees. Embedding of a genetic algorithm (GA) into a fault tree method to determine the heuristic optional design configuration of a reliable system; Use of a fault tree which can represent the failure causes of potential designs; Development and integration of GA into a fault-tree solver.

Developing cost‐effective, high‐efficiency, and stable electrocatalysts for the hydrogen evolution reaction (HER) in alkaline electrolytes is of critical importance for realizing renewable hydrogen technologies. However, the sluggish HER kinetics and unsatisfied stability remain critical challenges for their practical applications. Herein, a hierarchically porous phosphorized Pt‐Ni nanohexapod/N‐doped graphene aerogel (P‐PtNiNH/NGA) constructed by an oxidation‐phosphorization‐controlled reconfiguration strategy is presented. It enables fast water dissociation kinetics for an abundant supply of hydrogen ions, strong electron interaction for optimal intermediate adsorption, and an excellent anchoring effect of the NGA to avoid the aggregation and Ostwald ripening of the PtNiNHs, thus exhibiting superior activity and exceptional stability toward alkaline HER. The P‐Pt1Ni2NH/NGA exhibits an ultralow overpotential of 15 mV at a current density of 10 mA cm−2, a low Tafel slope of 37 mV dec−1, and long‐term stability, which are superior to commercial Pt/C. Moreover, the P‐Pt1Ni2NH/NGA shows a high mass activity of 13.4 mA µg−1 and a large TOF value of 13.5 s−1 at an overpotential of 100 mV, which are 8.8 times and 9.0 times higher than commercial Pt/C (under the same Pt loading of ≈9.1 µg cm−2). This work is of high inspiration for catalyst design to obtain ideal alkaline HER performance. [ABSTRACT FROM AUTHOR]

Objective: To review the research progress of subtype H vessels in the occurrence and development of osteonecrosis of the femoral head (ONFH)., Methods: The relevant domestic and foreign literature was extensively reviewed. The histological features, biological mechanism of subtype H vessels involved in promoting of osteogenesis, and the role and application of the subtype H vessels in ONFH were summarized., Results: The subtype H vessel is a newly discovered bone vessel, mainly distributed in metaphysis and subperiosteum, highly expressing endomucin and CD31. The subtype H vessel has a dense arrangement of Runx2 + early osteoprogenitors, collagen type Ⅰα + osteoblast cells, and Osterix + osteoprogenitors that have the ability to induce osteogenesis and angiogenesis. Factors such as platelet-derived growth factor BB, slit guidance ligand 3, hypoxia inducible factor 1α, Notch signaling pathway, and vascular endothelial growth factor are involved in the mechanism of subtype H vessels in promoting osteogenesis., Conclusion: Subtype H vessels play an important role in the regulation of angiogenesis and osteogenesis during bone tissue repair and reconstruction. The discovery of subtype H vessels provides new insights into the molecular and cellular mechanisms of osteogenesis and angiogenesis coupling. In the future, new techniques targeting the regulation of subtype H blood vessels may become a promising method for the treatment of ONFH.

Multistimuli-responsive enaminitrile-based configurational switches displaying aggregation-induced emission (AIE), fluorescence turn-on effects, and supergelation properties are presented. The E-isomers dominated (>97%) in neutral/basic solution, and the structures underwent precisely controlled switching around the enamine C═C bond upon addition of acid/base. Specific fluorescence output was observed in response to different external input in the solution and solid states. In response to H + , configurational switching resulted in complete formation of the nonemissive Z-H + -isomers in solution, however displaying deep-blue to blue fluorescence (Φ F up to 0.41) in the solid state. In response to Cu II in the solution state, the E-isomers exhibited intense, turn-on, blue-green fluorescence, which could be turned off by addition of competitive coordination. The acid/base-activated switching, together with the induced AIE-effects, further enabled the accomplishment of a responsive superorganogelator. In nonpolar solvents, a blue-fluorescent supramolecular gel was formed upon addition of acid to the E-isomer suspension. The gelation could be reversed by addition of base, and the overall, reversible process could be repeated at least five cycles.