Mesoporous carbon-containing voltammetric biosensor for determination of tyramine in food products

A voltammetric biosensor based on tyrosinase (TYR) was developed for determination of tyramine. Carbon material (multi-walled carbon nanotubes or mesoporous carbon CMK-3-type), polycationic polymer—i.e., poly(diallyldimethylammonium chloride) (PDDA), and Nafion were incorporated into titania dioxide sol (TiO(2)) to create an immobilization matrix. The features of the formed matrix were studied by scanning electron microscopy (SEM) and cyclic voltammetry (CV). The analytical performance of the developed biosensor was evaluated with respect to linear range, sensitivity, limit of detection, long-term stability, repeatability, and reproducibility. The biosensor exhibited electrocatalytic activity toward tyramine oxidation within a linear range from 6 to 130 μM, high sensitivity of 486 μA mM(−1) cm(−2), and limit of detection of 1.5 μM. The apparent Michaelis–Menten constant was calculated to be 66.0 μM indicating a high biological affinity of the developed biosensor for tyramine. Furthermore, its usefulness in determination of tyramine in food product samples was also verified. [Figure: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00216-016-9612-y) contains supplementary material, which is available to authorized users

Self-consumption of electricity from renewable sources

If the cost of energy production from renewable energy sources (RES) reduces below the level of electricity retail prices, self-consumption (SC) can contribute to market integration of RES. Support schemes such as feed-in tariffs could be phased out in view of parity of retail prices and RES production costs. In combination with electricity storage and demand response (DR), SC can facilitate the integration of variable renewables onto the grid and lower the overall costs of the energy system through load shifting particularly if storage and DR is managed using ICT and algorithms controlling charging cycles and usage of electric devices. Some issues remain however: Self-consumption potential is limited without further technical enhancements in storage or DR solutions. To organize self-consumption efficiently, measures on the grid side and energy storage have to be taken. Enabling the grid to provide necessary information back to prosumers and vice versa, as well as developing economic ways of storing energy is key to unleashing the potential that lies within the transition from passive consumers to active prosumers. Different policies, such as the support of investments to storage installations, can foster those developments. The impact of electricity retail prices has to be considered also. Self-consumption is profitable if the costs of locally produced RES are lower than the retail electricity price. There are, however, worries that a high penetration of self-consumption solutions might lead to an unfair distribution of network charges, taxes and levies even if storage and DR measures can lower additional costs arising from PV integration. Future energy policy can address the way how costs get allocated

Estimating contributions of pelagic and benthic pathways to consumer production in coupled marine food webs

1. Pelagic and benthic systems usually interact, but their dynamics and production rates differ. Such differences influence the distribution, reproductive cycles, growth rates, stability and productivity of the consumers they support. Consumer preferences for, and dependence on, pelagic or benthic production are governed by the availability of these sources of production and consumer life history, distribution, habitat, behavioural ecology, ontogenetic stage and morphology. 2. Diet studies may demonstrate the extent to which consumers feed on prey in pelagic or benthic environments. But they do not discriminate benthic production directly supported by phytoplankton from benthic production recycled through detrital pathways. The former will track the dynamics of phytoplankton production more closely than the latter. We develop and apply a new analytical method that uses carbon (C) and sulfur (S) natural abundance stable isotope data to assess the relative contribution of pelagic and benthic pathways to fish consumer production. 4. For 13 species of fish that dominate community biomass in the northern North Sea (estimated >90% of total biomass), relative modal use of pelagic pathways ranged from <25% to >85%. Use of both C and S isotopes as opposed to just C reduced uncertainty in relative modal use estimates. Temporal comparisons of relative modal use of pelagic and benthic pathways revealed similar ranking of species dependency over four years, but annual variation in relative modal use within species was typically 10-40%. 5. For the total fish consumer biomass in the study region, the C and S method linked approximately 70% and 30% of biomass to pelagic and benthic pathways respectively. As well as providing a new method to define consumers’ links to pelagic and benthic pathways our results demonstrate that a substantial proportion of fish biomass, and by inference production, in the northern North Sea is supported by production that has passed through transformations on the seabed

Data from: Estimating contributions of pelagic and benthic pathways to consumer production in coupled marine food webs

1. Pelagic and benthic systems usually interact, but their dynamics and production rates differ. Such differences influence the distribution, reproductive cycles, growth rates, stability and productivity of the consumers they support. Consumer preferences for, and dependence on, pelagic or benthic production are governed by the availability of these sources of production and consumer life history, distribution, habitat, behavioural ecology, ontogenetic stage and morphology. 2. Diet studies may demonstrate the extent to which consumers feed on prey in pelagic or benthic environments. But they do not discriminate benthic production directly supported by phytoplankton from benthic production recycled through detrital pathways. The former will track the dynamics of phytoplankton production more closely than the latter. 3. We develop and apply a new analytical method that uses carbon (C) and sulfur (S) natural abundance stable isotope data to assess the relative contribution of pelagic and benthic pathways to fish consumer production. 4. For 13 species of fish that dominate community biomass in the northern North Sea (estimated >90% of total biomass), relative modal use of pelagic pathways ranged from 85%. Use of both C and S isotopes as opposed to just C reduced uncertainty in relative modal use estimates. Temporal comparisons of relative modal use of pelagic and benthic pathways revealed similar ranking of species dependency over four years, but annual variation in relative modal use within species was typically 10-40%. 5. For the total fish consumer biomass in the study region, the C and S method linked approximately 70% and 30% of biomass to pelagic and benthic pathways respectively. As well as providing a new method to define consumers’ links to pelagic and benthic pathways our results demonstrate that a substantial proportion of fish biomass, and by inference production, in the northern North Sea is supported by production that has passed through transformations on the seabed

Future emerging technologies in the wind power sector: A European perspective

This paper represents an expert view from Europe of future emerging technologies within the wind energy sector considering their potential, challenges, applications and technology readiness and how they might evolve in the coming years. These technologies were identified as originating primarily from the academic sector, some start-up companies and a few larger industrial entities. The following areas were considered: airborne wind energy, offshore floating concepts, smart rotors, wind-induced energy harvesting devices, blade tip-mounted rotors, unconventional power transmission systems, multi-rotor turbines, alternative support structures, modular high voltage direct current generators, innovative blade manufacturing techniques, diffuser-augmented turbines and small turbine technologies. The future role of advanced multiscale modelling and data availability is also considered. This expert review has highlighted that more research will be required to realise many of these emerging technologies. However, there is a need to identify synergies between fundamental and industrial research by correctly targeting public and private funding in these emerging technology areas as industrial development may outpace more fundamental research faster than anticipated