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Of fundamental importance for the functioning of a community is the flow of energy and elements through its components. However, the question of how (if at all) the edge effect of habitats can drive elemental traits of organisms has hitherto been largely neglected issue in ecosystem ecology at the community level. We quantified the abundance of invertebrates and measured the elemental composition (K, Na, Ca, Mg, Cu, Zn, Fe, Mn, As, Cd, Co and Pb) of 15 different organisms within the plant-invertebrate food web (plant – oilseed rape pests/herbivores – pollinators = wild bees – saprovores – predators – parasitoids) sampled in 34 fields of a key bioenergy crop that is an exceptionally strong biodiversity driver, the oilseed rape. Then these were related to the individual field edge habitat features (including typically anthropogenic ones like dirt and tarred roads) measured within a 100 m radius around the invertebrate sampling sites. Our study showed that elemental traits of the plant-invertebrate food web components in oilseed rape crops varied owing to the habitat specificity determined at the relatively small spatial scale of an individual field, and that the elemental traits of these organisms differed from both an inter- and an intra-guild perspective. The major mechanistic explanation for most of these relationships seems to derive from the secondary gut content effect. Determining one single state for the homeostatic/stoichiometric regulation of chemical elements in invertebrates based on the application of whole-body metal concentrations is in principle impossible, because of the unknown noise caused by the inclusion of extracellular portions of metals in the analysis. It is thus imperative to develop consistent principles for assessing elemental traits of organisms that are based on highly sensitive and high-throughput analytical methods for the ionomic profiling of microsamples at the organ, tissue, cellular or even sub-cellular levels.

The ribonucleic acids (RNA) form highly folded structures, which behind the helical fragments contain several secondary and tertiary structural motives. All of them have an influence on thermodynamic stability of the RNA. The 5'- and 3'-dangling ends are one of those structural motives, which effect stability of the adjacent helixes. In this paper, we described the influence of 14 different modified nucleotides, placed as 3'-dangling ends, on thermal stability of the RNA duplexes. Collected data demonstrate that: (i) 5-substituents of the uridine have an impact on the 3'-dangling end effect and the largest changes were observed for 5-chloro, bromo and methyl substituents; (ii) position of the methyl group within the uracil residue affect the thermal stability of the duplex; (iii) increasing a size of the heterocycle base placed as the 3'-terminal unpaired nucleotide enhances stabilization of duplexes.