Astrid Avellan

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The transmission-virulence trade-off hypothesis is one of the few adaptive explanations of virulence evolution, and assumes that there is an overall positive correlation between parasite transmission and virulence. The shape of the transmission-virulence relationship predicts whether virulence should evolve toward either a maximum or to an intermediate(More)
This study focuses on the early temperamental (TTQ = toddler temperament questionnaire), behavioral (IBR = infant behavior record), and cognitive precursors of impaired language functioning in preschool-age pre-terms infants. The study group consisted of 63 pre-term infants with a mean birth weight of 1246 +/- 437 g born in 1989-1991 in the University(More)
Ge-imogolites are short aluminogermanate tubular nanomaterials with attractive prospected industrial applications. In view of their nano-scale dimensions and high aspect ratio, they should be examined for their potential to cause respiratory toxicity. Here, we evaluated the respiratory biopersistence and lung toxicity of 2 samples of nanometer-long(More)
The potential colloids release from a large panel of 25 solid industrial and municipal waste leachates, contaminated soil, contaminated sediments and landfill leachates was studied. Standardized leaching, cascade filtrations and measurement of element concentrations in the microfiltrate (MF) and ultrafiltrate (UF) fraction were used to easily detect(More)
The toxicity of high-aspect-ratio nanomaterials (HARNs) is often associated with oxidative stress. The essential nutrient Fe may also be responsible of oxidative stress through the production of reactive oxygen species. In the present study, it has been examined to what extent adding Fenton reaction promoting Fe impacted the toxicity of an alumino-germanate(More)
Ag0 and CuO engineered nanomaterials (ENMs), or their sulfidized forms are introduced into freshwater wetlands through wastewater effluent and agricultural runoff. Knowledge about the rates of transformations of these ENMs in realistic environments, and the impact of the form of the incoming ENM (i.e. sulfidized or pristine) on bioavailability and fate is(More)
Looking to reliability of high-k dielectrics, their behavior under electrical stress is very often determined by traps and charges. During the past years a strong focus of the reliability investigation was given to HfO<sub>2</sub>. However, especially LSTP as well as memory industry is going to use a silicon doped hafnium oxide (HfSiO<sub>x</sub>). Three(More)
In contrast to many nanotoxicity studies where nanoparticles (NPs) are observed to be toxic or reduce viable cells in a population of bacteria, we observed that increasing concentration of TiO2 NPs increased the cell survival of Bacillus subtilis in autolysis-inducing buffer by 0.5 to 5 orders of magnitude over an 8 hour exposure. Molecular investigations(More)
Terrestrial plants can internalize and translocate nanoparticles (NPs). However, direct evidence for the processes driving the NP uptake and distribution in plants is scarce at the cellular level. Here, NP-root interactions were investigated after 10 days of exposure of Arabidopsis thaliana to 10 mg·L-1 of negatively or positively charged gold NPs (∼12 nm)(More)
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