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Pastures are strongly affected by local environmental variables in terms of their species richness, plant composition and herbage production. A multi-site monitoring study was conducted over three years to investigate the influence of morphoclimatic factors on the seasonal variations in dry matter (DM) yield from Karst pastures. Seven sites located on the Italian and Slovenian Karst regions were investigated that differed in terms of their geological and geomorphological features, as well as their soil types. At each site, the daily DM yield (kg ha-1 d-1) was determined using Corral-Fenlon method which permits to simulate herbage utilization from grazing herds. The morphoclimatic features were also analysed, with the aim to evaluate the link between seasonal DM yield and geomorphological and environmental factors. Generalized non-linear mixed models were built to study the observed seasonal variations in DM yield, using day of the year (DOY), growing degree days (GDD), and cumulative rainfall. Furthermore, environmental descriptors were included in the model in order to evaluate their effects on DM yield. The seasonal variations in yield showed two growing periods (spring and late summer), which were described by Gaussian curves. For the spring growing period, the model improved when the interaction between soil granulometry and growing degree days corresponding to the curve peak was taken into account. This confirms the influence of soil type and air temperature on pasture yield. For the late summer growing period, the interaction between the sand classes and the number of rainy days from the beginning of the period to the peak of the curve improved the model. The curve parameters of our models are correlated with environmental descriptors depending on the lithology and particle size of soils. The results are essential for the optimization of pasture management and avoiding degradation due to over- or under-grazing., Competing Interests: Dolomiti Project provided support in the form of salaries for author Stefano Furin, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Thus, this does not alter our adherence to PLOS ONE policies on sharing data and materials. Geotema srl provided support in the form of salaries for author Valentina Vincenzi and Luca Minarelli. It was partner in the project BioDiNet funded by the European programme of cross-border collaboration (Slovenia-Italy 2007–2013). It was in charge of study and describe the hydro-geological characteristics of the area where the study presented in the manuscript was conducted. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

The peptide toxin bombolitin III [B(III)], originally isolated from bumblebee venom, has been shown to undergo a concentration-dependent conformational change from a random structure to an alpha-helix induced by aggregation. The aggregation process and the consequent folding results from a delicate balance of electrostatic and hydrophobic interactions. The conformational change is strongly dependent on pH and salt concentration. In order to gain insight on the structure of the aggregates, and in particular, on the aggregation number and relative orientation of helices in the molecular complexes, the following analogue of bombolitin III was designed and synthesized: Ile-Lys-Bpa-Met-Asp-Ile-Leu-Ala-Lys-Leu-Gly-Lys-Val-Leu-Ala-His-Val-NH2 Bpa3-B(III) where Bpa is benzoylphenylalanine. Bpa3-B(III) aggregates were investigated by CD and nmr techniques. The observed nuclear Overhauser effect pattern accounts for an antiparallel orientation of two distinct helices. The Bpa side chain allows for the photoinduced cross reaction with any aliphatic proton in spatial proximity. After irradiation, the reaction mixture was analyzed by high performance liquid chromatography and electrospray mass spectrometry. The results confirmed the presence of dimeric and trimeric complexes of bombolitin III formed upon interhelix cross-linking.