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1. Canonic‐Like HER Activity of Cr 1– x Mo x B 2 Solid Solution: Overpowering Pt/C at High Current Density

   https://doi.org/10.1002/adma.202000855  

   Park, Hyounmyung ; Lee, Eunsoo ; Lei, Ming ; Joo, Hyunkeun ; Coh, Sinisa ; Fokwa, Boniface P. T. ( June 2020 , Advanced Materials)

   Abundant transition metal borides are emerging as substitute electrochemical hydrogen evolution reaction (HER) catalysts for noble metals. Herein, an unusual canonic‐like behavior of theclattice parameter in the AlB₂‐type solid solution Cr_1–xMo_xB₂(x= 0, 0.25, 0.4, 0.5, 0.6, 0.75, 1) and its direct correlation to the HER activity in 0.5 M H₂SO₄solution are reported. The activity increases with increasingx, reaching its maximum atx= 0.6 before decreasing again. At high current densities, Cr_0.4Mo_0.6B₂outperforms Pt/C, as it needs 180 mV less overpotential to drive an 800 mA cm⁻²current density. Cr_0.4Mo_0.6B₂has excellent long‐term stability and durability showing no significant activity loss after 5000 cycles and 25 h of operation in acid. First‐principles calculations have correctly reproduced the nonlinear dependence of theclattice parameter and have shown that the mixed metal/B layers, such as (110), promote hydrogen evolution more efficiently forx= 0.6, supporting the experimental results.

    

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2. n2v : A density‐to‐potential inversion suite. A sandbox for creating, testing, and benchmarking density functional theory inversion methods

   https://doi.org/10.1002/wcms.1617  

   Shi, Yuming ; Chávez, Victor H. ; Wasserman, Adam ( January 2022 , WIREs Computational Molecular Science)
3. Incorporation of density scaling constraint in density functional design via contrastive representation learning

   https://doi.org/10.1039/D3DD00114H  

   Gong, Weiyi ; Sun, Tao ; Bai, Hexin ; Chowdhury, Shah Tanvir ; Chu, Peng ; Aryal, Anoj ; Yu, Jie ; Ling, Haibin ; Perdew, John P. ; Yan, Qimin ( October 2023 , Digital Discovery)

   We demonstrate that contrastive representation learning is a computationally efficient and flexible method to incorporate physical constraints, especially those defined by equalities, in machine-learning-based density functional design.

    

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4. Structural and functional characterization of three Type B and C chloramphenicol acetyltransferases from Vibrio species

   https://doi.org/10.1002/pro.3793  

   Alcala, Ashley ; Ramirez, Guadalupe ; Solis, Allan ; Kim, Youngchang ; Tan, Kemin ; Luna, Oscar ; Nguyen, Karen ; Vazquez, Daniel ; Ward, Michael ; Zhou, Min ; et al ( December 2019 , Protein Science)

   Chloramphenicol acetyltransferases (CATs) were among the first antibiotic resistance enzymes identified and have long been studied as model enzymes for examining plasmid‐mediated antibiotic resistance. These enzymes acetylate the antibiotic chloramphenicol, which renders it incapable of inhibiting bacterial protein synthesis. CATs can be classified into different types: Type A CATs are known to be important for antibiotic resistance to chloramphenicol and fusidic acid. Type B CATs are often called xenobiotic acetyltransferases and adopt a similar structural fold to streptogramin acetyltransferases, which are known to be critical for streptogramin antibiotic resistance. Type C CATs have recently been identified and can also acetylate chloramphenicol, but their roles in antibiotic resistance are largely unknown. Here, we structurally and kinetically characterized threeVibrioCAT proteins from a nonpathogenic species (Aliivibrio fisheri) and two important human pathogens (Vibrio choleraeandVibrio vulnificus). We found all three proteins, including one in a superintegron (V. cholerae), acetylated chloramphenicol, but did not acetylate aminoglycosides or dalfopristin. We also determined the 3D crystal structures of these CATs alone and in complex with crystal violet and taurocholate. These compounds are known inhibitors of Type A CATs, but have not been explored in Type B and Type C CATs. Based on sequence, structure, and kinetic analysis, we concluded that theV. choleraeandV. vulnificusCATs belong to the Type B class and theA. fisheriCAT belongs to the Type C class. Ultimately, our results provide a framework for studying the evolution of antibiotic resistance gene acquisition and chloramphenicol acetylation inVibrioand other species.

    

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5. Density Functional Response Calculations of Dispersion Coefficients C 6 and C 9 of Closed- and Open-Shell Systems

   https://doi.org/10.1021/acs.jpca.2c03610  

   Abella, Laura ; Autschbach, Jochen ( September 2022 , The Journal of Physical Chemistry A)