Abstract The paper studies the initial boundary value problem related to dynamic evolution of an elastic beam interacting with a substrate through elastic-breakable forcing term. This discontinuous interaction is aimed model phenomenon attachment-detachment occurring in adhesion phenomena. We prove existence solutions energy space and exhibit various counterexamples uniqueness. Furthermore we c...

In this paper we investigate the electron-phonon contribution to the resistivity of suspended single-layer graphene. In-plane as well as flexural phonons are addressed in different temperature regimes. We focus on the intrinsic electron-phonon coupling due to the interaction of electrons with elastic deformations in the graphene membrane. The competition between screened deformation potential v...

We show that the interaction between flexural phonons, when corrected by the exchange of electron-hole excitations, may drive the graphene sheet into a quantum critical point characterized by the vanishing of the bending rigidity of the membrane. Ripples arise then due to spontaneous symmetry breaking, following a mechanism similar to that responsible for the condensation of the Higgs field in ...

PURPOSE This study evaluated the degree of conversion (DC) of four indirect resin composites (IRCs) with various compositions processed in different polymerization units and investigated the effect of thermal aging on the flexural strength and Vicker's microhardness. MATERIALS AND METHODS Specimens were prepared from four IRC materials, namely Gr 1: Resilab (Wilcos); Gr2: Sinfony (3M ESPE); G...

Quasi-static cyclic tests on reinforced concrete (RC) walls have shown that shear deformations can constitute a significant ratio of the total deformations when the wall is loaded beyond the elastic regime. For slender RC walls that form a stable flexural mechanism, the ratio of shear to flexural deformations remains approximately constant over the entire range of imposed displacement ductiliti...

Seawalls are sheltering structures used for protecting the coastal regions against wave induced forces. Because of random nature of the wave behavior, application of physical models for the study of wave-structure interaction can be quite efficient. In the present research, physical models of thin flexible walls were constructed and tested in a wave flume subject to generated random waves. The ...

The instantaneous displacement, velocity and acceleration of a cantilever tip impacting onto a graphite surface are reconstructed. The total dissipated energy and the dissipated energy per cycle of each excited flexural mode during the tip interaction is retrieved. The tip dynamics evolution is studied by wavelet analysis techniques that have general relevance for multi-mode atomic force micros...

BACKGROUND It is unclear whether eczema prevalence is truly increasing worldwide. OBJECTIVE We sought to investigate worldwide secular trends in childhood eczema. METHODS Children (n = 302,159) aged 13 to 14 years in 105 centers from 55 countries and children aged 6 to 7 years (n = 187,943) in 64 centers from 35 countries were surveyed from the same study centers taking part in Phase One an...