Salicylic acid (SA) is a plant hormone, which is involved in the defense responses to pathogens and to abiotic stress, and in the regulation of plant growth and development. The shikimate pathway... Show moreSalicylic acid (SA) is a plant hormone, which is involved in the defense responses to pathogens and to abiotic stress, and in the regulation of plant growth and development. The shikimate pathway end product chorismic acid serves as the precursor for salicylic acid. In the model plant Arabidopsis thaliana. Chorismate is converted to salicylic acid by a chloroplast-localized isochorismate synthase and an unidentified isochorismate pyruvate lyase. EDS5, a member of the multidrug and toxin extrusion (MATE) transporter family, localized in the chloroplast envelope is responsible for SA transport from the chloroplasts to the cytosol. SA triggers a local defense response as well as a systemic defense response through the whole plant. The first objective in this thesis focused on transcription factors for the regulation of EDS5 gene expression. The second objective was to identify the missing enzyme with isochorismate pyruvate lyase activity. Show less
In mechanical metamaterials, large deformations can occur in systems which are topological from the point of view of linear waves. The interplay between such nonlinearities and topology affects... Show moreIn mechanical metamaterials, large deformations can occur in systems which are topological from the point of view of linear waves. The interplay between such nonlinearities and topology affects wave propagation. Beyond perfectly periodic systems, defects provide a way to modify and control the properties of metamaterials, and can also interact with both nonlinearities and the bulk topology. To investigate these, we explore the wave propagation in three mechanical models, i.e.~solitary waves in topological rotor chains, lattice waves in twisted kagome networks, and transverse shock waves in flexible strings. Show less
