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Since their discovery in 2011, interest in MXenes, two-dimensional transition metal carbides and/or nitrides, has greatly expanded due to their promising functional properties and facile synthesis methods, and their development for emerging technologies is propitiously progressing. Despite promising advancements, there still remains a lack of understanding with regards to their fundamental mechanical properties. Here, nanoindentation of the Tin+1CnTx MXenes was studied via atomistic simulations utilizing a parametrization of the ReaxFF interatomic potential, to understand the influence of point defects. From force-displacement curves, the Young’s moduli of pristine Ti3C2O2 and Ti2CO2 were calculated to be 466 GPa and 983 GPa, respectively. The influence of both titanium and carbon vacancies (VTi and VC) on Ti3C2O2 were also quantified using simulated nanoindentation of a set of samples containing both 1% VTi and 10% VC, resulting in a reduction of the calculated Young’s modulus to 386 ± 31 GPa. Of particular importance, is that these results mirror recent experimental findings indicating the fundamental role of defects in the mechanical behavior of MXenes. The calculated modulus in this work for the defect-containing Ti3C2O2 surpasses that of graphene oxide, establishing it as a new benchmark in strength for solution-processed, 2D materials. Results here also indicate improvements can be made in current MXene processing methods to better approach the theoretical strength of pristine 2D materials.

Purpose Team cognition is known to be an important predictor of team process and performance. DeChurch and Mesmer-Magnus (2010) reported the results of an extensive meta-analytic examination into the role of team cognition in team process and performance, and documented the unique contribution of team cognition to these outcomes while controlling for the motivational dynamics of the team. Research on team cognition has exploded since the publication of DeChurch and Mesmer-Magnus’ meta-analysis, which raises the question: to what extent do the effect sizes reported in their 2010 meta-analysis still hold with the inclusion of newly published research? The paper aims to discuss this issue. Design/methodology/approach The authors updated DeChurch and Mesmer-Magnus’ meta-analytic database with newly published studies, nearly doubling its size, and reran their original analyses examining the role of team cognition in team process and performance. Findings Overall, results show consistent effects for team cognition in team process and performance. However, whereas originally compilational cognition was more strongly related to both team process and team performance than was compositional cognition, in the updated database, compilational cognition is more strongly related to team process and compositional cognition is more strongly related to team performance. Originality/value Meta-analyses are only as generalizable as the databases they are comprised of. Periodic updates are necessary to incorporate newly published studies and confirm that prior findings still hold. This study confirms that the findings of DeChurch and Mesmer-Magnus’ (2010) team cognition meta-analysis continue to generalize to today’s teams.