Measuring linguistic complexity in long-term L2 speakers of English and L1 attriters of German

Linguistic complexity is neither easily defined nor measured. The challenge in finding reliable ways to measure linguistic complexity is even more pronounced when the variation of contexts in which complexity is measured is taken into account. This paper therefore aims at finding measures for assessing syntactic and lexical complexity that are sensitive and non-overlapping even in a less frequently studied context: spontaneous speech of L1 attriters and highly proficient L2 English speakers. To evaluate operationalizations of syntactic and lexical complexity, several previously proposed measures are applied to a corpus of spontaneous speech and a principal component analysis is conducted. The results show which of the measures group together as underlying variables of syntactic and lexical complexity and how this can inform future operationalizations of complexity

Space weathering simulations through controlled growth of iron nanoparticles on olivine

Airless planetary bodies are directly exposed to space weathering. The main spectral effects of space weathering are darkening, reduction in intensity of silicate mineral absorption bands, and an increase in the spectral slope towards longer wavelengths (reddening). Production of nanophase metallic iron (npFe0) during space weathering plays major role in these spectral changes. A laboratory procedure for the controlled production of npFe0 in silicate mineral powders has been developed. The method is based on a two-step thermal treatment of low-iron olivine, first in ambient air and then in hydrogen atmosphere. Through this process, a series of olivine powder samples was prepared with varying amounts of npFe0 in the 7-20 nm size range. A logarithmic trend is observed between amount of npFe0 and darkening, reduction of 1 µm olivine absorption band, reddening, and 1 µm band width. Olivine with a population of physically larger npFe0 particles follows spectral trends similar to other samples, except for the reddening trend. This is interpreted as the larger, ~40-50 nm sized, npFe0 particles do not contribute to the spectral slope change as efficiently as the smaller npFe0 fraction. A linear trend is observed between the amount of npFe0 and 1 µm band center position, most likely caused by Fe2+ disassociation from olivine structure into npFe0 particles.Peer reviewe

Cenoura / Carrot (Daucus carota L.): mela / podridão-mole / soft rot

Apresenta cenouras com lesões em diversos estágios de desenvolvimento provocadas pela podridão-moleComponente Curricular::Educação Superior::Ciências Agrárias::Agronomi