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Steel-ultrahigh performance concrete (UHPC) lightweight composite deck (LWCD) is a new countermeasure against fatigue issues for orthotropic steel decks (OSDs). While fatigue response of the steel deck plate in LWCDs is complex: except for normal stress ranges developed in steel deck plate, shear stress ranges are generated in headed stud shear connectors, so the steel deck plate at stud root position is under a complex coupled fatigue response. This paper aims to reveal the coupled fatigue behavior of the steel deck plate in LWCDs. First, three OSD-UHPC composite beam specimens were tested under cyclic flexural loads and the steel deck plates were acted by both normal and shear stress ranges. The tests indicate that although the equivalent fatigue stress ranges in the steel deck plate exceeded the fatigue strengths specified in the Chinese design code for steel-concrete composite bridges, the steel deck plate at stud root position did not develop fatigue failures, indicating that the coupled fatigue strength specified in the design code is applicable for LWCDs. Next, an FE analysis was performed to reveal the coupled fatigue response of the steel deck plate in the LWCD. The distribution of the index values reflecting the coupled fatigue effect was obtained, and the maximum value of the coupled effect was S max = 0.85, which is lower than the limit value (S lim = 1.3), implying that the steel deck plate at stud root position should be safe under coupled fatigue actions. Further, a parametric analysis was accomplished to reveal the influence of primary parameters on the coupled fatigue effect. • Fatigue tests were conducted to reveal the coupled fatigue behavior of the steel deck plate in LWCD. • The coupled fatigue design method for normal composite bridges was verified to be applicable for LWCDs. • The coupled fatigue effect of the steel deck plate was revealed through a detailed FE analysis. • The coupled fatigue effect caused by different factors was obtained via parametric analyses. [ABSTRACT FROM AUTHOR]

The development of simplified synthetic strategy to create structurally and functionally diverse pseudo‐natural macrocyclic molecules is highly appealing but poses a marked challenge. Inspired by natural scaffolds, herein, we describe a practical and concise ligand‐enabled Pd(II)‐catalyzed sp3 C−H alkylation, olefination and arylation macrocyclization, which could offer a novel set of pseudo‐natural macrocyclic sulfonamides. Interestingly, the potential of ligand acceleration in C−H activation is also demonstrated by an unprecedented enantioselective sp3 C−H alkylation macrocyclization. Moreover, a combination of in silico screening and biological evaluation led to the identification of a novel spiro‐grafted macrocyclic sulfonamide 2 a, which showed a promising efficacy for the treatment of Parkinson's disease (PD) in a mouse model through the activation of silent information regulator sirtuin 3 (SIRT3). [ABSTRACT FROM AUTHOR]

The development of simplified synthetic strategy to create structurally and functionally diverse pseudo‐natural macrocyclic molecules is highly appealing but poses a marked challenge. Inspired by natural scaffolds, herein, we describe a practical and concise ligand‐enabled Pd(II)‐catalyzed sp3 C−H alkylation, olefination and arylation macrocyclization, which could offer a novel set of pseudo‐natural macrocyclic sulfonamides. Interestingly, the potential of ligand acceleration in C−H activation is also demonstrated by an unprecedented enantioselective sp3 C−H alkylation macrocyclization. Moreover, a combination of in silico screening and biological evaluation led to the identification of a novel spiro‐grafted macrocyclic sulfonamide 2 a, which showed a promising efficacy for the treatment of Parkinson's disease (PD) in a mouse model through the activation of silent information regulator sirtuin 3 (SIRT3). [ABSTRACT FROM AUTHOR]