Large-scale spatial pattern of bird responses to a potential predator suggests that predator-specific mobbing is a plastic trait

Journal of Ethology - Mobbing is a prey antipredator behaviour aimed to reduce the risk of predation. The behaviour may be innate and/or learned. Evaluating this behaviour on a large spatial scale...     

Social assessment of miscanthus cultivation in Croatia: Assessing farmers' preferences and willingness to cultivate the crop

Social aspects of miscanthus cultivation have been investigated in a limited way in the scientific literature. Adopting existing frameworks for social life-cycle assessment enables assessments to include numerous social aspects; however, the relevance of these aspects depends on the local context. This study aims to identify the most relevant social aspects from the farmers' perspective using a previously proposed framework for the assessment of the stakeholder ‘farmer’. It is based on a case study for miscanthus production in Sisak Moslavina in Croatia. The existence of abandoned lands in Croatia presents an opportunity for the cultivation of miscanthus as a potential source of biomass for the production of bio-based materials and fuels. The study seeks to assess the feasibility of cultivating miscanthus in the region, taking into account potential challenges and opportunities, as well as farmers' willingness to adopt the crop, and to understand the reasons behind land abandonment. We conducted a survey among 44 farmers in the region and used a scoring method to identify the most relevant social aspects. The aspects most valued by the farmers were health and safety, access to water, land consolidation and rights, income and local employment, and food security. Responses to the question of whether they would adopt the crop highlight the importance of an established market, good trading conditions and profitability of cultivation. The survey also enabled an understanding of farmers' preferences with respect to the production conditions of crops. The farmers regarded the provision of subsidies as one of the main factors that render a crop attractive. Opportunities for the adoption of the miscanthus cultivation include high yields and low input requirements. Barriers include land conflicts and land availability. Despite the opportunities for miscanthus development in the region, there are important challenges to consider for successful implementation of the crop.     

Dehydration-induced changes in spectral reflectance indices and chlorophyll fluorescence of Antarctic lichens with different thallus color,and intrathalline photobiont

In this study, we investigated responses of the Photochemical Reflectance Index (PRI), and Normalized Difference Vegetation Index (NDVI) to gradual dehydration of several Antarctic lichen species (chlorolichens: Xanthoria elegans, Rhizoplaca melanophthalma, Physconia muscigena, cyanolichen: Leptogium puberulum), and a Nostoc commune colony from fully wet to a dry state. The gradual loss of physiological activity during dehydration was evaluated by chlorophyll fluorescence parameters. The experimental lichen species differed in thallus color, and intrathalline photobiont. In the species that did not exhibit color change with desiccation (X. elegans), NDVI and PRI were more or less constant (mean of 0.25, ??0.36, respectively) throughout a wide range of thallus hydration status showing a linear relation to relative water content (RWC). In contrast, the species with apparent species-specific color change during dehydration exhibited a curvilinear relation of NDVI and PRI to RWC. PRI decreased (R. melanophthalma, L. puberulum), increased (N. commune) or showed a polyphasic response (P. muscigena) with desiccation. Except for X. elegans, a curvilinear relation was found between the NDVI response to RWC in all species indicating the potential of combined ground research and remote sensing spectral data analyses in polar regions dominated by lichen flora. The chlorophyll fluorescence data recorded during dehydration (RWC decreased from 100 to 0%) revealed a polyphasic species-specific response of variable fluorescence measured at steady state—F_s, effective quantum yield of photosystem II (Φ_PSII), and non-photochemical quenching (qN). Full hydration caused an inhibition of Φ_PSII in N. commune while other species remained unaffected. The dehydration-dependent fall in Φ_PSII was species-specific, starting at an RWC range of 22–32%. Critical RWC for Φ_PSII was around 5–10%. Desiccation led to a species-specific polyphasic decrease in F_s and an increase in qN indicating the involvement of protective mechanisms in the chloroplastic apparatus of lichen photobionts and N. commune cells. In this study, the spectral reflectance and chlorophyll fluorescence data are discussed in relation to the potential of ecophysiological processes in Antarctic lichens, their resistance to desiccation and survival in Antarctic vegetation oases.     

Material model of pelvic bone based on modal analysis: a study on the composite bone

Biomechanics and Modeling in Mechanobiology - Digital models based on finite element (FE) analysis are widely used in orthopaedics to predict the stress or strain in the bone due to...     

Extract of <Emphasis Type="Italic">Microcystis</Emphasis> water bloom affects cellular differentiation in filamentous cyanobacterium <Emphasis Type="Italic">Trichormus variabilis</Emphasis> (Nostocales,Cyanobacteria)

Cyanobacteria produce a wide spectrum of biologically active compounds such as microcystins, whose effects on photoautotrophic organisms and role in the aquatic ecosystems have been most intensively discussed and studied. In our study, we examined effects of semipurified Microcystis extract containing microcystins (0.2–20 nM corresponding to 0.2–20 μg L⁻¹) on age-induced cell differentiation of filamentous cyanobacterium Trichormus variabilis. The heterocyst and akinete formation was significantly decreased after exposure to extract containing 2 or 20 nM of microcystins within 10 days of exposure. To our knowledge, this is the first information about effects of metabolites produced by planktonic cyanobacteria on cell differentiation in filamentous cyanobacteria. Since the effects were induced by environmentally relevant concentrations of microcystins, our observations may indicate not only that microcystins or other bioactive peptides could affect conservation, overwintering, and nitrogen-fixation in filamentous cyanobacteria under environmental conditions but also contribute to the understanding of possible signaling function of cyanobacterial metabolites.     

Beech forest management does not affect the infestation rate of the beech scale Cryptococcus fagisuga across three regions in Germany

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Imidazo[1,2‐c]pyrimidin‐5(6H)‐one as a novel core of cyclin‐dependent kinase 2 inhibitors: Synthesis,activity measurement,docking, and quantum mechanical scoring

We report on the synthesis, activity testing, docking, and quantum mechanical scoring of novel imidazo[1,2‐c]pyrimidin‐5(6H)‐one scaffold for cyclin‐dependent kinase 2 (CDK2) inhibition. A series of 26 compounds substituted with aromatic moieties at position 8 has been tested in in vitro enzyme assays and shown to inhibit CDK2. 2D structure‐activity relationships have ascertained that small substituents at position 8 (up to the size of naphtyl or methoxyphenyl) generally lead to single‐digit micromolar IC₅₀ values, whereas bigger substituents (substituted biphenyls) decreased the compounds' activities. The binding modes of the compounds obtained using Glide docking have exhibited up to 2 hinge‐region hydrogen bonds to CDK2 and differed in the orientation of the inhibitor core and the placement of the 8‐substituents. Semiempirical quantum mechanics‐based scoring identified probable favourable binding modes, which will serve for future structure‐based design and synthetic optimization of substituents of the heterocyclic core. In summary, we have identified a novel core for CDK2 inhibition and will explore it further to increase the potencies of the compounds and also monitor selectivities against other protein kinases.