- Stable Solutions to Some Elliptic Problems: Minimal Cones, the Allen-Cahn Equation, and Blow-Up Solutions. - Isoperimetric Inequalities for Eigenvalues of the Laplacian. - Topological Aspects of Critical Points and Level Sets in Elliptic PDEs. - Symmetry Properties for Solutions of Higher-Order Elliptic Boundary Value Problems. - Recent Trends in Free Boundary Regularity.