Knudsen layer losses of tail fuel ions can significantly reduce the fusion reactivity of multi-keV DT in capsules with small fuel ρr; sizable yield reduction can result for small inertial confinement fusion (ICF) capsules. This effect is most pronounced when the distance from a burning DT gas region to a nonreacting or cold wall is comparable to the mean free path of reacting fuel ions. A simplified asymptotic theory of Knudsen layer tail depletion is presented and a nonlocal reduced fusion reactivity model is obtained. Application of the model in simulations of ICF capsule implosion experiments gives calculated yields and ion temperatures that are in much closer agreement with observations than are the results of "nominal" or mixed simulations omitting the model.

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New educators may feel overwhelmed by the options available for engaging students through classroom participation. However, it may be helpful to recognize that participatory pedagogical systems often have constructivist roots. Adopting a constructivist perspective, our paper considers three meta-practices that encourage student participation: designing activities, leading others, and assessing peers. We explored the consequences of these meta-practices for important student outcomes, including content knowledge, engagement, self-efficacy, sense of community, and self-awareness. We found that different meta-practices were associated with different combinations of outcomes. This discovery demonstrates the benefit of studying metapractices so as to reveal the nuanced effects that may arise from pedagogical choices. In addition, an understanding of meta-practices can help leadership educators to be more discerning and intentional in their course designs.