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Aspects of the catalyst surface, including the active sites and the presence of surface termination groups and their distribution, influence the overall catalytic activity. Surface reconstruction of the catalyst modulates catalytically active sites, and the availability of these active sites affects the catalytic performance. The present work explores materials from the 2D class known as MXenes for catalytic activity using density functional theory. We systematically determined the equilibrium coverage of the termination group over the MXene surface using the Monte Carlo simulation and cluster expansion method by considering various adsorbate–adsorbate interactions of the termination groups. To identify the origin of the equilibrium coverage and understand its behaviour, the adsorbate–adsorbate interaction was further detailed to its fundamental subcomponents. To understand the effect of termination group coverage, hydrogen evolution reactions (HERs) were studied over pristine, fully terminated surface and surface with equilibrium coverage. We also incorporated the various factors that affect the HER activity, such as the type and placement of termination groups and different stacking configurations of MXenes. It was observed that the stacking configuration, type of surface termination groups, their distribution over the MXene surface, and their equilibrium coverage were the key factors that controlled the HER activity of MXenes. [ABSTRACT FROM AUTHOR]

Chromosome congression and alignment are essential for cell cycle progression and genomic stability. Kinesin‐7 CENP‐E, a plus‐end‐directed kinesin motor, is required for chromosome biorientation, congression and alignment in cell division. However, it remains unclear how chromosomes are aligned and segregated in the absence of CENP‐E in mitosis. In this study, we utilize the CRISPR‐Cas9 gene editing method and high‐throughput screening to establish CENP‐E knockout cell lines and reveal that CENP‐E deletion results in defects in chromosome congression, alignment and segregation, which further promotes aneuploidy and genomic instability in mitosis. Both CENP‐E inhibition and deletion lead to the dispersion of spindle poles, the formation of the multipolar spindle and spindle disorganization, which indicates that CENP‐E is necessary for the organization and maintenance of spindle poles. In addition, CENP‐E heterozygous deletion in spleen tissues also leads to the accumulation of dividing lymphocytes and cell cycle arrest in vivo. Furthermore, CENP‐E deletion also disrupts the localization of key kinetochore proteins and triggers the activation of the spindle assembly checkpoint. In summary, our findings demonstrate that CENP‐E promotes kinetochore‐microtubule attachment and spindle pole organization to regulate chromosome alignment and spindle assembly checkpoint during cell division. [ABSTRACT FROM AUTHOR]