Existence and multiplicity results for resonant fractional boundary value problems

We study a Dirichlet-type boundary value problem for a pseudo-differential equation driven by the fractional Laplacian, with a non-linear reaction term which is resonant at infinity between two non-principal eigenvalues: for such equation we prove existence of a non-trivial solution. Under further assumptions on the behavior of the reaction at zero, we detect at least three non-trivial solutions (one positive, one negative, and one of undetermined sign). All results are based on the properties of weighted fractional eigenvalues, and on Morse theory

Nonlinear second-order multivalued boundary value problems

In this paper we study nonlinear second-order differential inclusions involving the ordinary vector $p$-Laplacian, a multivalued maximal monotone operator and nonlinear multivalued boundary conditions. Our framework is general and unifying and incorporates gradient systems, evolutionary variational inequalities and the classical boundary value problems, namely the Dirichlet, the Neumann and the periodic problems. Using notions and techniques from the nonlinear operator theory and from multivalued analysis, we obtain solutions for both the `convex' and `nonconvex' problems. Finally, we present the cases of special interest, which fit into our framework, illustrating the generality of our results.Comment: 26 page

Three nontrivial solutions for the p-Laplacian Neumann problems with a concave nonlinearity near the origin

We consider a nonlinear Neumann problem driven by the p- Laplacian, with a right-hand side nonlinearity which is concave near the origin. Using variational techniques, combined with the method of upper-lower solutions and with Morse theory, we show that the problem has at least three nontrivial smooth solutions, two of which have a constant sign (one positive and one negative).FCTPOCI/MAT/55524/200

Resonant nonlinear periodic problems with the scalar p-Laplacian and a nonsmooth potential

We study periodic problems driven by the scalar p-Laplacian with a nonsmooth potential. Using the nonsmooth critical point theory for locally Lipsctiz functions,we prove two existence theorems under conditions of resonance at infinity with respect to the first two eigenvalues of the negative scalar p-Laplacian with periodic boundary conditions.Universidade de Aveir

M&A Performance: Market’s Initial Reaction as an Unbiased Indicator of Post-acquisition Performance

This paper investigates the reliability of the stock market’s initial reaction to M&A announcements as a predictor of actual post-acquisition performance. The two prevailing methods for evaluating M&A performance are event studies (stock market-based measures) and accounting-based measures. The present study combines these two performance evaluation approaches in a single empirical examination. Both the post-merger buy-and-hold abnormal returns and changes in ROA are used as actual post-acquisition performance variables. The acquirer’s cumulative abnormal return (CAR) around the announcement is used as the market predictor variable. An econometric model is employed to test the predictive power of the announcement-period CAR on the actual performance variables using a sample of 3,208 acquisitions by U.S. public companies from 2010 to 2014. This paper’s main contribution lies both in its methodology and its findings: on the one hand, long-term market and accounting variables are used as dependent variables measuring post-acquisition performance. On the other hand, this paper finds that short-term CAR is not a good predictor of subsequent M&A performance. The results suggest that the acquirer’s prior M&A experience is a positive predictor of post-acquisition performance