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Recent advances in complex networks research allow to take a closer look at various ecological interactions that involve both plants and animals at the level of ecosystems. Especially mutualistic interactions (eg. pollination) play a crucial role in generating and sustaining biodiversity of terrestrial ecosystems. Many authors regard them as "architecture of biodiversity" because usually they connect dozens or even hundreds of species, forming large and complex networks of reciprocally beneficial interactions. The structure of such networks is highly heterogeneous and asymmetric: most of the species are rather weakly connected, while some of taxa develop much stronger relationships. Based on our studies in semi-natural habitats in NE Poland we will demonstrate how new mathematical tools allow to analyse the pollination network structure and can be farther applied to indicate "keystone" species which may be important in determining the stability of the studied ecosystems. [ABSTRACT FROM AUTHOR]

Visual floral characters play an important role in shaping plant-pollinator interactions. The genus Fritillaria L. (Liliaceae), comprising approximately 140 species, is described as displaying a remarkable variety of flower colours and sizes. Despite this variation in visual floral traits of fritillaries, little is known about the potential role of these features in shaping plant-pollinator interactions. Here, we seek to clarify the role of visual attraction in species offering a robust food reward for pollinators early in the spring, which is the case for Fritillaria. We also searched for potential tendencies in the evolution of floral traits crucial for plant-pollinator communication. The generality of species with green and purple flowers may indicate an influence of environmental factors other than pollinators. The flowers of the studied species seem to be visible but not very visually attractive to potential pollinators. The food rewards are hidden within the nodding perianth, and both traits are conserved among fritillaries. Additionally, visual floral traits are not good predictors of nectar properties. When in the flowers, pollinators are navigated by nectar guides in the form of contrasting nectary area colouration. Flower colour does not serve as a phenotypic filter against illegitimate pollinators—red and orange bird-pollinated fritillaries are visible to bees. [ABSTRACT FROM AUTHOR]

Several data sets from the Silurian and Ordovician formations from three wells on the shore of Baltic Basin in Northern Poland prepared on the basis of well logging data and results of their comprehensive interpretation were used in factor analysis. The goal of statistical analysis was structure recognition of data and proper selection of parameters to limit the number of variables in study. The top priority of research was recognition of specific features of claystone/mudstone formations predisposing them to be potential shale gas deposits. The identified data scheme based on data from one well, was then applied to: 1) well 2 and well 3 separately, 2) combined data from three wells, 3) depth intervals treated as sweet spots, i.e., formations of high hydrocarbon potential. Numbers of samples from well logging were proportional to number of laboratory data from individual formations. The extended data set comprising all available log samples in explored formations was also prepared. Outcomes from standard (Triple Combo—natural gamma log, resistivity log, neutron log and bulk density log and Quad Combo—with addition of sonic log and spectral gamma log) and sophisticated (GEM™—Elemental Analysis Tool, Wave Sonic and Nuclear Magnetic Resonance—NMR) logs were the basis for data sets. Finally, laboratory data set of huge amount of variables from elemental, mineralogical, geochemical and petrophysical laboratory experiments was built and verified in FA to select the most informative components. Conclusions on the data set size, number of factors and type of variables were drawn. [ABSTRACT FROM AUTHOR]

• Research on a prototype 4-hole orifice with module m = 0.25. • CFD modeling for two turbulence models: k - ε -realizable and k -ω- BSL. • A high accuracy numerical model was developed for Re = 4200–19,000. • The experimental results for volumetric flows in range 0.167–0.686 dm3/s. • Numerical simulations for multihole orifice flowmeter. • The experimental research was found to be very compatible with simulations. In this research study, the comprehensive metrological analysis is investigated for a 4-hole orifice with module m = 0.25 installed in the pipeline with an internal diameter of 50 mm. A detailed numerical simulation was performed for the turbulence models: k-ε-realizable and k- ω -BSL. The novelties of the research include model validation by comparing the results of numerical studies with the experiment conducted in the area of developing turbulent flow in the range of Reynolds numbers from 4,200 to 19,000. Such validated models are sought by the system designers and can be used for further analyses and optimisation of this orifice in this flow type. The multi-hole orifices are less sensitive to flow disturbances than the standardized standard centric orifice. In addition, orifices of this type can be mounted in installations with much shorter sections upstream and downstream of the orifice - which is very often the case in industrial flow installations. [ABSTRACT FROM AUTHOR]

• Mass flow rate measurement using a segmental orifice with a module m = 0.25. • The flow type analysis for Reynolds numbers Re = 9,000 to 17,000. • Monte Carlo simulations and experiments on the laboratory stand were conducted. • The resulting relative uncertainty of flow rate measurement does not exceed 1.8% for the tested orifice. Segmental orifices are often used to measure flows of heterogeneous mixtures, especially in flow meters in the power industry, for example. The orifice (with module m = 0.25) was installed in a stainless-steel pipe with internal diameter of 50 mm, placed in a hydraulic water system. The research was performed for Reynolds numbers ranging from 9,000 to 17,000. The flow characteristics of this orifice obtained based on simulation in SolidWorks Flow Simulation 2014 and experimental data were compared with standard-based calculations. It was determined that relative differences between the obtained flow characteristics did not exceed 1.5% for the experiment and 5.1% for the simulation. The article also presents the results of estimated uncertainty for mass flow measurement q m using the analytical method and the Monte Carlo simulations. The results for both methods proved that the relative expanded uncertainty U rel (q m) does not exceed 1.8% for the tested orifice. [ABSTRACT FROM AUTHOR]

• Mass flow rate measurement using a centric and eccentric orifice with diameter ratio ß = 0.5. • Analysis of the impact of the flow type (for Reynolds numbers Re = 10,000 ... 20,000) on the flow rate measurement uncertainty. • Comparison of the impact of the type of orifice used on the uncertainty of flow rate measurement. • Monte Carlo simulations and experiments on the laboratory stand were used. • The resulting relative uncertainty of flow rate measurement does not exceed 2.1% for both orifice types. The article analyses the impact of the Reynolds number on the estimated uncertainty of the mass flow rate measurement using an orifice plate. The objects of the research were two types of orifices: centric (ISA) and eccentric, with the diameter ratio β = 0.5. Studies were performed by Monte Carlo simulation and experiments for Reynolds numbers in the range 10,000 ≤ Re ≤ 20,000. The obtained results have shown that for both orifice types, the results obtained from the experiments and from the Monte Carlo simulation are similar. The nature of changes in the expanded uncertainty of the flow measurement is very similar for each type. For the both types of orifices, the value of the expanded uncertainty of the flow measurement increases linearly with the increasing Reynolds number. [ABSTRACT FROM AUTHOR]

Variations between fruit cultivars can significantly impact their biochemical composition. The present research examined the variability in the qualitative and quantitative content of phenolic compounds in berry extracts of Actinidia kolomikta and Actinidia arguta cultivars. Additionally, antioxidant activities of berry extracts were evaluated. The total phenolic, flavonoid, proanthocyanidin contents and hydroxycinnamic acid derivatives were determined using the appropriate methodologies. The average amount of phenolic compounds in A. kolomikta berries (177.80 mg/g) was three times higher than that of A. arguta (54.45 mg/g). Our findings revealed that berries of A. kolomikta and A. arguta accumulated, on average, 1.58 RE/g DW (rutin equivalent/g dry weight) and 0.615 mg RE/g DW of total flavonoids, 1439.31 mg EE/g DW (epicatechin equivalent/g dry weight) and 439.97 mg EE/g DW of proanthocyanidins, and 23.51 mg CAE/g DW (chlorogenic acid equivalent/g dry weight) and 5.65 mg CAE/g DW of hydroxycinnamic acid derivatives, respectively. The cultivars of both species were characterized by higher antioxidant activity of total phenolic compounds determined using CUPRAC and FRAP methods compared to the ABTS •+ method. The variability in phenolic compounds' qualitative and quantitative content in tested berry extracts was evaluated by applying ultra-high performance liquid chromatography (UHPLC) coupled to mass spectrometry in tandem with electrospray ionization. Significant intraspecific differences in the amounts of total phenolic compounds, total flavonoid compounds, proanthocyanidins, and hydroxycinnamic acid derivatives were determined among cultivars. Four phenolic acids, eight flavonols, two flavones, and five flavon-3-ols were identified in the berry extracts.

The design of radiation measurement systems includes a modelling phase which ascertains the best 3D geometry for a projected gauge. To simulate measured counts by a detector, the widely-used rigorous phenomenological model is used. However, this model does not consider possible source or/and detector movement during a measurement interval. Therefore, the phenomenological model has been successfully modified in order to consider such a displacement during the time sampling interval in dynamic experiments. To validate the proposed model, a simple radiation system was accurately implemented in the MCNP5 code. The experiments confirmed the accuracy of the proposed model., (Copyright © 2016 Elsevier Ltd. All rights reserved.)