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In the present study, we investigated the effect of supercritical carbon-oxide (scCO2) extraction on antioxidant capacity, enzyme inhibitory potential, and levels of ergosterol and ganoderic acid in both cultivated and wild-grown G. lucidum. Extraction yields were slightly higher for wild samples (1.29%) than for cultivated ones (1.13%). The levels of ganoderic acid and ergosterol were higher in cultivated in comparison to wild samples. In addition, the total phenolic content in cultivated samples (13.42 mg GAE g−1) was higher than in wild samples (10.38 mg GAE g−1). In general, cultivated samples exhibited stronger antioxidant potential when compared with wild ones. Regarding enzyme inhibitory properties, it was validated that the wild samples (14.01 mg OE g−1) possessed greater lipase activity in comparison to cultivated samples (5.36 mg OE g−1). Based on our findings, cultivated G. lucidum might be considered a valuable source of natural bioactive agents in the preparation of health-promoting products.

In this work, we analyze performances of the unmanned aerial vehicle- (UAV-) assisted wireless powered sensor communication, where sensor transmission ability is supported by the UAV. Harvested energy from the UAV-broadcasted signal is further used at the sensor nodes for uplink information transmission to the UAV, over assumed shadowed κ − μ fading channels. Here, we observe a general scenario in which due to the flight conditions of the UAV, the channels content include the LOS components affected by the shadowing effect, modeled by the general shadowed κ − μ channel model, which can be reduced to other well-known channel models as its special cases. We derive closed-form expressions for the outage probability (OP) of such wireless sensor network (WSN) operating in shadowed κ − μ fading environments. Further, we analyze the optimization of time allocation to minimize OP subjected to UAV's energy constraints. The impact of channel parameters on observed performance measures is analyzed, and obtained results are numerically validated. Caslav Stefanovic would like to acknowledge CONEX-Plus programme. The CONEX-Plus is funded by UC3M, the European Commission through the Marie Sklodowska Curie COFUND Action (H2020-MSCA-COFUND-2017- GA 801538).

With progressing urbanisation, treatment of urban stormwater is a vital issue that should be addressed to ensure good water quality in receiving water bodies. Treatment may be performed near the source, with different filter systems using various filter materials, or by using an end-of-pipe method, e.g. a stormwater pond. One constraint in the urban environment is the lack of available space in developed areas, where stormwater treatment facilities are needed the most. Methods developed to treat the stormwater runoff have been the focus of previous studies but the increasing standards of water quality and increasing land constraint pressures demand the further development of stormwater treatment systems. Both laboratory and field experiments are necessary to understand and improve the treatment processes as well as to evaluate how the implemented methods perform under field conditions. The aim of the thesis was to increase the knowledge about the components in stormwater treatment systems that can be used in area-efficient treatment facilities. In order to compare four potential stormwater filter materials (peat, bark, air-blown polypropylene and milkweed), column experiments were carried out using synthetic stormwater that simulated road runoff. Experiments were carried out to evaluate the impacts of the ageing of synthetic stormwater quality during laboratory testing, including dissolved metal concentrations and their impact on the estimation of filter efficiency. In a field study, a full-scale application of a zeolite filter installation was investigated, with a focus on service life and the efficiency of treating copper roof runoff. In order to further investigate a novel sedimentation device, a bottom grid structure (BGS), promoting sediment settling in a smaller area of a stormwater pond, a hydraulic modelling study was conducted to investigate the impact of the cell geometry of the structure on sediment settling and the impact of the structure on pond maintenance and sediment resuspension. The column tests of four different filter materials showed that bark and peat had higher treatment efficiency for dissolved metals than milkweed and polypropylene, with the order of efficiency being peat>bark>milkweed>polypropylene. All four of the filter materials showed a total metal reduction of over 70%, which could be due to the separation of particle-bound metals in the columns. The ageing of the synthetic stormwater showed that dissolved metals, particularly copper, decreased in concentration, quite rapidly. During one experiment run, the dissolved copper concentration was reduced to 15% of its initial value. In order to account for the concentration changes an equation was proposed that normalised the concentration of dissolved metal over the duration of the experiment. During the observation period of 16 months, the zeolite installation removed 52% to 82% and 48% to 94% of total and dissolved copper, respectively. However, the effluent concentrations were still high (360-600 μg/l). There was also an indication of the decreasing filter performance over time with a prediction that the treatment level of total copper would drop to approximately 25% by the end of the service life of three years. The hydraulic experiments on a scaled model of a BGS showed that wider cells were on average 13% more efficient in trapping the particles than the narrower variant. The cell wall angle also had an impact (tilted walls added to the sedimentation efficiency), although the applicability of such cell structures can be questioned, as this cell shape may hinder maintenance efforts. It was also hypothesised that the inclusion of the BGS in the pond reduces the area needed for sediment settling, thus making the pond more area-efficient and easier to include in an urbanised setting.

Stormwater sediments of various sizes and densities are recognised as one of the most important stormwater quality parameters that can be conventionally controlled by settling in detention ponds. The bottom grid structure (BGS) is an innovative concept proposed in this study to enhance removal of stormwater sediments entering ponds and reduce sediment resuspension. This concept was studied in a hydraulic scale model with the objective of elucidating the effects of the BGS geometry on stormwater sediment trapping. Towards this end, the BGS cell size and depth, and the cell cross-wall angle were varied for a range of flow rates, and the sediment trapping efficiency was measured in the model. The main value of the observed sediment trapping efficiencies, in the range from 13 to 55%, was a comparative assessment of various BGS designs. In general, larger cells (footprint 10 × 10 cm) were more effective than the smaller cells (5 × 5 cm), the cell depth exerted small influence on sediment trapping, and the cells with inclined cross-walls proved more effective in sediment trapping than the vertical cross-walls. However, the BGS with inclined cross-walls would be harder to maintain. Future studies should address an optimal cell design and testing in an actual stormwater pond. Validerad;2020;Nivå 2;2020-05-05 (alebob)

peer-reviewed, The aim of the present work was to examine if hydrogen peroxide treatment of sugar beet fibre that aimed at improving its physicochemical properties would impair its antioxidant potential. Three different sugar beet fibres were obtained from sugar beet – non-treated fibre (NTF) from sugar beet cossettes extracted with sulphurous acid, treated fibre (TF) from NTF treated with hydrogen peroxide in alkaline solution and commercially available Fibrex®. The antioxidant activity of extractable and non-extractable fibre fractions in ethanol/water mixture (80:20, v/v) of three fibre samples was estimated. Non-extractable fractions obtained after alkaline treatment of investigated fibres were much higher in phenolic compounds and possessed higher antioxidant potential than extractable fractions. Ferulic acid was proven to be the dominant phenolic acid. Regarding both extractable and non-extractable fractions, Fibrex® had the highest antioxidant activity in chemical tests, while NTF was superior in comparison with TF. Based on the results of Caco-2 cells-based test, all non-extractable fractions possessed potential for reactive oxygen species inhibition. Regarding the extractable fractions, only the TF manifested this effect., This work was financially supported by the Ministry of Education, Science and Technological Development, Republic of Serbia (project no: TR-31014 and project no: TR-31029).