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With the rapid booming of intelligent traffic system, vehicular ad hoc networks have attracted wide attention from both academic and industry. However, security is the main obstacle for the wide deployment of vehicular ad hoc networks. Vehicular ad hoc networks security has two critical issues: access authentication and privacy preservation. How to ensure privacy preservation and improve the efficiency of authentication has become the urgent needs. However, the existing access authentication schemes for vehicular ad hoc networks with different flaws cannot maintain the balance between security and efficiency. Thus, an anonymous access authentication scheme for vehicular ad hoc networks under edge computing based on ID-based short group signature mechanism is proposed in this article to improve the efficiency and anonymity of access authentication. Multiple pseudonyms are presented to preserve the privacy of vehicle node. Besides, a new method is designed to identify and revoke malicious vehicles in the evaluation manner. The core protocols of the proposed scheme are proved to be secure by SVO logic. According to the computation cost and transmission overhead analysis, we indicate that our scheme owns better performance. Moreover, in this article, we combine vehicular ad hoc networks with edge computing together to provide a new clue for the development of mobile edge computing. [ABSTRACT FROM AUTHOR]

This article proposes an evolutionary multiagent framework of the co-operative co-evolutionary multiobjective model (CCMO-EMAS), specifically for equipment layout optimization in engineering. In this framework, each agent is set in a multiobjective cooperative co-evolutionary mode along with the algorithms and corresponding settings. In each iteration, agents are executed in turn, and each agent optimizes a subpopulation from system decomposition. Additionally, the collaboration mechanism is addressed to build complete solutions and evaluate individuals in the co-operative co-evolutionary algorithm. Each subpopulation is optimized once, and the corresponding agent is evaluated based on the improvement of the system memory. Moreover, the agent team is also evolved through an elite genetic algorithm. Finally, the proposed CCMO-EMAS framework is verified in a multimodule satellite equipment layout problem. [ABSTRACT FROM AUTHOR]

Summary: The electrocatalytic CO2 reduction reaction (CO2RR) can convert greenhouse gases into high value‐added carbon‐based fuels and chemicals, providing a sustainable way to solve the energy and environmental crisis. Currently, AuCu bimetallic alloys are attracting attention because of their potential to customize the catalytic activity. In this work, the stability of Au and AuCu bimetallic clusters are systematically studied by first principles calculation. On this basis, the AuCu cluster catalyst is simulated using the density functional theory (DFT) to detect its catalytic activity for the reduction of CO2 to CH3OH. The calculation results show that the AuCu clusters with symmetry have the best stability. Moreover, the doping of Cu atoms in the Au6 cluster can reduce the reaction barrier to a certain extent, thereby accelerating the reaction. Among them, Au1Cu5 and Au2Cu4 cluster catalysts have the most obvious catalytic effects. In the last step, the energy can be reduced by about 2.688 and 5.404 kcal·mol−1, respectively, which can realize the synergistic catalytic effect of Au and Cu on CO2RR. This work can be helpful for the design and preparation of high‐efficiency bimetallic cluster catalysts for CO2RR to CH3OH. [ABSTRACT FROM AUTHOR]

Objectives. To purify and characterize the glutathione binding protein GsiB of glutathione importer (GSI) in Escherichia coli (E. coli). Results. The coding sequence of GsiB was cloned from E. coli MG1655 and expressed in BL21(DE3). GsiB protein was expressed and purified to homogeneity using Ni-affinity and gel filtration chromatography. SDS-PAGE of purified GsiB showed a single protein band of molecular mass 56 kDa, while native gel showed two bands around 56 kDa and 110 kDa. Gene knockout showed that GsiB was essential for GSI mediated glutathione import. Interactions of GsiA, B, C, and D were determined using bacterial two-hybrid method. Without glutathione, GsiB showed no direct interaction with the other three proteins. However, GsiB could interact with GsiC and GsiD when using glutathione as sole sulfur source. Conclusions. GsiB functions in E. coli was characterized which could help elucidate the glutathione import mechanism in gram-negative bacteria. [ABSTRACT FROM AUTHOR]