Let X\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {X}$$\end{document} be a class of groups. A group G is called a X\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {X}$$\end{document}-critical group if G∉X\documentclass[12pt]{minimal}
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\begin{document}$$G \not \in \mathcal {X}$$\end{document} whereas every proper subgroup of G is in X\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {X}$$\end{document}. We call G a pd-group if |G| is divisible by a prime p. A group G is called a X\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {X}$$\end{document}-semicritical group with respect to a prime p if G∉X\documentclass[12pt]{minimal}
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\begin{document}$$G \not \in \mathcal {X}$$\end{document}, but every proper pd-subgroup of G is in X\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {X}$$\end{document}. Let U\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {U}$$\end{document} be a class of supersolvable groups. In this paper, we mainly study the U\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {U}$$\end{document}-semicritical groups with respect to 2. Furthermore, we describe the non-solvable groups whose every 2d-maximal subgroup is U\documentclass[12pt]{minimal}
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\begin{document}$$\mathcal {U}$$\end{document}-semicritical groups with respect to 2.