Charaterizing RDF graphs through graph-based measures - Framework and assessment

The topological structure of RDF graphs inherently differs from other types of graphs, like social graphs, due to the pervasive existence of hierarchical relations (TBox), which complement transversal relations (ABox). Graph measures capture such particularities through descriptive statistics. Besides the classical set of measures established in the field of network analysis, such as size and volume of the graph or the type of degree distribution of its vertices, there has been some effort to define measures that capture some of the aforementioned particularities RDF graphs adhere to. However, some of them are redundant, computationally expensive, and not meaningful enough to describe RDF graphs. In particular, it is not clear which of them are efficient metrics to capture specific distinguishing characteristics of datasets in different knowledge domains (e.g., Cross Domain vs. Linguistics). In this work, we address the problem of identifying a minimal set of measures that is efficient, essential (non-redundant), and meaningful. Based on 54 measures and a sample of 280 graphs of nine knowledge domains from the Linked Open Data Cloud, we identify an essential set of 13 measures, having the capacity to describe graphs concisely. These measures have the capacity to present the topological structures and differences of datasets in established knowledge domains

Analysis of microbiologically stimulated biomass of Salix viminalis L. in the presence of CD2plus under in vitro conditions - implications for phytoremediation

AbstractThe efficiency of phytoremediation might be highly affected by plant-associated microorganisms, and understanding of the underlying mechanisms is still a great challenge. The primary aim of this study was to evaluate the efficiency parameters for Cd2+accumulation in the biomass of willow (Salix viminalis) as well as to define the biochemical response of the host plant when it is inoculated with selected bacterial strains (Massiliasp. andPseudomonassp.) or saprophytic fungus (Clitocybesp.) under controlledin vitroconditions. Inoculation of plants with bacterial strains affected the efficiency of phytoremediation process and was expressed as the quantity of accumulated Cd (Q), the bioaccumulation factor (BCF) and the translocation index (Ti); however, the effect was strain and plant organ specific. The level of hydrogen peroxide (H2O2), which is both an indicator of plant response to biological and/or abiotic environmental stress and a molecule involved in plant-microbial interactions, decreased under the influence of Cd2+in uninoculated plants (plant growth was inhibited by Cd2+) and increased in the inoculated variants of plants growing in the presence of Cd2+(microbiologically stimulated biomass). The saprophytic fungusClitocybesp. generally stimulated biomass and increased the level of H2O2synthesis in all the investigated plant organs and variants of the experiment. We suggest that determination of phytoremediation efficiency, and biochemical response (H2O2) of the host plant underin vitroconditions can help in predicting the final effect of plant-microbial systems in further field trials.</jats:p

Research of the biodegradability of degradable/biodegradable plastic material in various types of environments

Research of the biodegradability of degradable/biodegradable plastic material in various types of environments. Research was carried out in order to assess biodegradability of degradable/biodegradable materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive) or made of polyethylene (PE) with the addition of pro-oxidant additive (d2w additive), advertised as 100% degradable or certified as compostable within various types of environments. Research conditions were: (i) controlled composting environment – laboratory-scale, (ii) real composting conditions – domestic compost bin, (iii) real composting conditions – industrial composting plant and (iv) landfill conditions. The results demonstrate that the materials made of HDPE and mixed with totally degradable plastic additive (TDPA additive) or made of polyethylene (PE) with the addition of pro- -oxidant additive (d2w additive) or advertised as 100% degradable did not biodegrade in any of the above-described conditions and remained completely intact at the end of the tests. Biodegradation of the certified compostable plastic bags proceeded very well in laboratory-scale conditions and in real composting conditions – industrial composting plant, however, these materials did not biodegrade in real composting conditions – domestic compost bin and landfill conditions

Waste management law by example of a small European commune

The aim of this article was to present the rules governing the waste management system (WMS) and identify the changes emerging as a result of new regulations being introduced by example of Wołomin commune. European, Polish and Czech regulations clearly indicate the value of the hierarchy of waste management (WM). A response to the amended law was the modification of the WMS in communes, including the Wołomin commune. Based on performed analysis and discussions, it can be stated that the municipal waste management system (MWMS) in the commune of Wołomin meets the requirements imposed by the legislator, works efficiently and positively influences the condition of the natural environment. In addition, the information obtained has been generalized and compared with the situation in the Czech Republic (CR)

Microbial assisted phytoextraction of Cd²⁺ by Salix viminalis under in vitro culture conditions

Microbially assisted phytoremediation is considered as the most promising eco-friendly solution for recultivation of heavy metal polluted soils. In vitro experiments can be favorable systems that allow assessing compatibility and efficiency of both partners (e.g. plant-microorganism) which reduces time and space in the initial stages of this technology. The main objective of this study was: (1) to calculate the Cd2+ accumulation factors (e.g. BCF, Ti, AF) using willow (Salix viminalis L.) inoculated with three Streptomyces sp. strains under in vitro conditions and (2) to compare obtained results with that derived from pot experiments by Złoch et al. (2017). Our results reveal significantly increase in Cd2+ accumulation capacity of Streptomyces spp. inoculated wil- low plants, indicating microbial stimulation of phytoextraction. Additionally, inoculated plants showed higher biomass production and lower lipids peroxidation level. The results revealed significant increase of MEA, BCF, Ti, MER by Strep-1 and Strep-2 in the above-ground parts of inoculated plants. Moreover, of the three strains tested, Strep-1 (Streptomyces sp. SIIB-Zn-R8) demonstrated the highest impact on the Cd2+ phytoextraction efficiency. In conclusion, the proposed in vitro model system allowed predicting Cd2+ phytoextraction capacity per- formed using inoculated willow plants with the significant reduction of both time and space

Benthic cyanobacteria on coral reefs of Moorea Island (French Polynesia) : diversity response to habitat quality

The marine benthic cyanobacteria on coral reefs of Moorea Island (French Polynesia) show significant changes in species diversity in response to environmental impacts. To study these changes in cyanobacterial diversity, we examined pristine and degraded coral reefs by combining microscopy of morphological properties of the taxa with characterization of each by 16S rRNA gene sequences. A total of 30 cyanobacterial species have been recorded, of which 10 (33%) of them represent a new record for Moorea Island. The majority of morpho-species we identified could be distinguished by phylogenetic analyses of 61 sequences. Our survey results showed a sharp distinction in the composition of benthic cyanobacterial assemblages from healthy (high living coral cover) versus degraded habitats (low live coral cover due to anthropogenic activities). Finally, 21 bloom-forming species were identified, occurring mostly in environmentally impacted area (north coast). Blooms were dominated by three species: Anabaena sp.1, Hydrocoleum majus-B, Lyngbya majuscula. This study provides novel insights into the taxonomy of tropical benthic cyanobacteria as important environmental indicators and advocates the use of new bioevaluative tools for the management of coral reef environments

Fiber Quality of Hemp (Cannabis sativa L.) Grown in Soil Irrigated by Landfill Leachate Water

Hemp (Cannabis sativa L.) for industrial use is often considered as a renewable resource for cultivation in polluted areas, on one hand, for the purpose of possible remediation of soil and, on the other hand, for wide options of the possible use of plant material after the harvest in such areas, namely hemp fiber. This study summarizes the effects of landfill leachate irrigation on agronomic parameters and fiber properties in two cultivars of hemp has grown and harvested in two consecutive seasons. Cultivar Bialobrzeskie shows more promising results in terms of total fiber content and phloem fiber content, while it tends to sacrifice the density of both xylem and phloem fiber in comparison to cultivar Monoica. The two cultivars also demonstrate different sensitivity and responses to the presence of heavy metals, namely zinc and chromium