Lianas (woody vines) are important components of tropical forests and are known to compete with host trees for resources, decrease tree growth and increase tree mortality. Given the observed increases in liana abundance in some forests and their impacts on forest function, an integrated understanding of carbon dynamics of lianas and liana-infested host trees is critical for improved prediction of tropical forest responses to climate change. Non-structural carbohydrates (NSC) are the main substrate for plant metabolism (e.
View Article and Find Full Text PDFTropical forests face increasing climate risk, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, [Formula: see text]) and hydraulic safety margins (for example, HSM) are important predictors of drought-induced mortality risk, little is known about how these vary across Earth's largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation.
View Article and Find Full Text PDFAnt-plant defensive mutualism is a widely studied phenomenon, where ants protect their host plants (myrmecophytes) against herbivores in return for the provision of nesting sites and food. However, few studies addressed the influence of ant colonization and herbivory on the plant's metabolism. We chose the Amazonian plant , living in association with cf.
View Article and Find Full Text PDFNon-structural carbohydrates (NSC) are major substrates for plant metabolism and have been implicated in mediating drought-induced tree mortality. Despite their significance, NSC dynamics in tropical forests remain little studied. We present leaf and branch NSC data for 82 Amazon canopy tree species in six sites spanning a broad precipitation gradient.
View Article and Find Full Text PDFWhile seasonal influenza vaccines are usually non-adjuvanted, H1N1pdm09 vaccines were formulated with different squalene-containing adjuvants, to enable the reduction of antigen content thus increasing the number of doses available. To comparatively assess the effects of these adjuvants on antibody responses against matched and mismatched strains, and to correlate antibody levels with protection from disease, ferrets were immunized with 2μg of commercial H1N1pdm09 vaccine antigen alone or formulated with different licensed adjuvants. The use of squalene-containing adjuvants increased neutralizing antibody responses around 100-fold, and resulted in a significantly reduced viral load after challenge with a matched strain.
View Article and Find Full Text PDFProtease activation mutants of the highly pathogenic avian influenza virus A/FPV/Rostock/34 (H7N1) have been generated that are fully dependent on the presence of trypsin for growth in cell culture. Unlike wild-type virus, the mutants do not induce systemic infection in chicken embryos and show low pathogenicity in both chicken embryos and adult chickens. Inactivated vaccines prepared from the mutants protected chickens and mice very efficiently against infection with highly pathogenic wild-type virus in a cross-reactive manner.
View Article and Find Full Text PDFHaemagglutination-inhibition (HI) and virus neutralisation (VN) assays are routinely applied to evaluate influenza vaccine immunogenicity for regulatory approval. Despite their frequent use both assays are currently only poorly standardised causing considerable inter-laboratory variation of serological results that is particularly evident for pandemic influenza vaccines. The present study was conducted in association with the European Medicines Agency (EMA) to directly compare assay variability between vaccine manufacturer's and European regulatory agency's laboratories in an influenza pandemic scenario.
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