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This study evaluated differences between two strains of Ceriporiopsis subvermispora on improving the nutritive value and in vitro degradability of wheat straw.Wheat straw was treated with the fungi for 7 weeks. Weekly samples were analysed for ergosterol content, in vitro gas production (IVGP), chemical composition and lignin-degrading enzyme activity. Ergosterol data showed CS1 to have a faster initial growth than CS2 and reaching a stationary phase after 3 weeks. The IVGP of CS1-treated wheat straw exceeded the control earlier than CS2 (4 vs 5 weeks). CS1 showed a significantly higher (P < 0·001) selectivity in lignin degradation compared to CS2. Both strains showed peak activity of laccase and manganese peroxidase (MnP) at week 1. CS1 showed a significantly higher (P < 0·001) laccase activity, but lower (P = 0·008) MnP activity compared to CS2.Both CS strains improved the nutritive value of wheat straw. Variation between strains was clearly demonstrated by their growth pattern and enzyme activities.The differences among the two strains provide an opportunity for future selection and breeding programs in improving the extent and selectivity of lignin degradation in agricultural biomass.

Based on a 3-year (2011-2013) dataset of 10-min records collected at 10, 20, 40, and 80 m from the met mast of Cabauw, a time-varying investigation of the wind shear coefficient (WSC) relationship with atmospheric stability was addressed. WSC interdaily and interannual variability was analysed according to a 2-D combined representation, which confirmed a clear oval-shaped "solar shadow" caused by solar warming observed during diurnal unstable hours, and large WSCs occurring under strong stable conditions during the summer nights.Three different power law based approaches were compared to extrapolate wind resource to the turbine hub height according to the following WSC settings: (i) site's previously measured overall yearly average; (ii) site's previously measured stability-varying yearly averages; (iii) 10-min theoretically predicted values by applying the Panofsky and Dutton (PD) model. The latter proved to be the finest approach, providing extrapolated wind resource biased by 1-5% and energy yield by 5.51-10.57%, and showing the highest accuracy occurring under the most frequent (and most energetic) neutral conditions, when Weibull distribution's tail including the highest wind speed bins is particularly finely reproduced.This work confirmed how instrumental availability of detailed information on site's atmospheric stability classification is for wind energy studies.

Biodegradation rates of benzoate and related aromatic compounds, 3-nitrobenzoate, 4-chlorobenzoate, 4-chlorophenol, and 2,4-dichlorophenol by unexposed (unacclimated) and long-term exposed (acclimated) biomass were quantified using a modified fed-batch technique. The acclimated biomass was taken after approximately 1-year of operation from three lab-scale sequencing batch reactors (SBR). These reactors were operated under various cycling electron acceptor conditions with a continuous feed of a synthetic wastewater containing biogenic and nonbiogenic chemicals including benzoate, 3-nitrobenzoate, and 4-chlorophenol, but not 4-chlorobenzoate or 2,4-dichlorophenol. The unexposed biomass was taken from a full-scale wastewater treatment plant, which constituted one of the original sources of inoculum for the lab-scale SBRs. The acclimated biomass manifested high removal rates of benzoate and related aromatic compounds with additional removal of structurally similar chemicals (4-chlorobenzoate and 2,4-dichlorophenol). The unacclimated biomass showed no removal of 3-nitrobenzoate, 4-chlorobenzoate or 2,4-dichlorophenol. Addition of biogenic substrates reduced the degradation of most aromatic compounds tested, but it enhanced 2,4-dichlorophenol removal. Biodegradation rates of each aromatic compound with the biomass from the anoxic/aerobic SBR were further determined under anaerobic (absence of aeration and NO3-), anoxic (no aeration, but with surplus NO3-), standard oxygen (DO > 0.2 mg/L), and elevated oxygen (DO > 25 mg/L) conditions. The removal rate of both benzoate and 3-nitrobenzoate decreased under anaerobic condition but not under the anoxic condition; 4-chlorophenol biodegradation, on the other hand, was reduced significantly under both anoxic and anaerobic conditions. The removal rates of aromatic compounds, particularly those of 3-nitrobenzoate and 2,4-dichlorophenol, increased significantly under elevated dissolved oxygen conditions. Our results demonstrated that when the biochemical conditions shifted from oxygen-respiration to nitrate respiration, to anaerobiosis, the biodegradation rates of test aromatic compounds decreased or ceased.

Artículos en revistas Hybrid microgrids are expected to play an important role in the expansion of access to electricity in developing countries. While most of these systems are operated with dispatch strategies which do not make use of predictions about the load or about the availability of renewable energy resources, forecast-based strategies have recently gained attention as an alternative to bring down operation costs. In this work, we develop a framework to assess this potential under a range of assumptions about the quality of load and photovoltaic generation forecasts. The application of the methodology to a village of 600 households reveals cost savings ranging between 2% and 7% depending on the forecast quality and the composition of the microgrid. We also show that sizing microgrid components under the assumption of a predictive operation strategy results in a design with a higher share of intermittent generation. info:eu-repo/semantics/publishedVersion

The residential sector accounts for one-fifth of global energy consumption, resulting from the requirements to heat, cool, and light residential dwellings. It is therefore not surprising that energy efficiency in the residential market has gained importance in recent years. In this paper, we examine awareness, literacy and behavior of households with respect to their residential energy expenditures. Using a detailed survey of 1721 Dutch households, we measure the extent to which consumers are aware of their energy consumption and whether they have taken measures to reduce their energy costs. Our results show that "energy literacy" and awareness among respondents is low: just 56% of the respondents are aware of their monthly charges for energy consumption, and 40% do not appropriately evaluate investment decisions in energy efficient equipment. We document that demographics and consumer attitudes towards energy conservation, but not energy literacy and awareness, have direct effects on behavior regarding heating and cooling of the home. The impact of a moderating factor, measured by thermostat settings, ultimately results in strong variation in the energy consumption of private consumers. (C) 2013 Published by Elsevier B.V.

Agricultural biotechnology dates from the last two decades of the twentieth century. It involves the creation of plants and animals with new useful traits by inserting one or more genes taken from other species. New legal possibilities for patenting transgenic organisms and isolated genes have been provided to promote the development of this new technology. The applications of biotechnology raise a whole range of value issues, like consumer and farmer autonomy, respect for intellectual property, environmental sustainability, food security, social justice, and economic growth. Hitherto the field has not yet witnessed any deliberate attempt at value-sensitive design or design for values. The reason is that under the influence of strong commercial motivations, applications have been developed first and foremost with simple agronomic aims in view, such as herbicide tolerance and insect resistance, traits which are based on single genes. The opportunities for value-sensitive design appear to be constrained by the special character of the biological domain. Many desirable traits like drought tolerance are genetically complex traits that cannot be built into organisms by the insertion of one or a few genes. Another problem is that nature tends to fight back, so that insects become immune to insect-resistant crops and weeds become invulnerable to herbicides. This leads to the phenomenon of perishable knowledge, which also calls the so-called patent bargain into question. The possibilities for value-sensitive design will likely increase with synthetic biology, a more advanced form of biotechnology that aims at making biology (more) “easy to engineer.” Practitioners of this new field are acutely aware of the need to proceed in a socially responsible way so as to ensure sufficient societal support. Yet synthetic biologists are currently also engaged in a fundamental debate on whether they will ultimately succeed in tackling biological complexity.

AbstractProjections show that biomass will remain important for reaching future EU renewable energy targets. In addition to using domestic biomass, European bioenergy markets will also partly rely on imports of biomass, in particular in trade‐oriented EU member states like the United Kingdom, the Netherlands, Belgium, and Denmark. There has been a lot of debate on the sustainability of (imported) biomass and how policy should deal with this. In this research, therefore, we defined long‐term strategies for sustainable biomass imports in European bioenergy markets. We used the input of different stakeholders in our approach through focus‐group discussions and a global survey, focusing on the following aspects: key principles of sustainable biomass trade, risks and opportunities of biomass trade, both for import regions (EU countries) and for sourcing regions, and practical barriers for trade. Overall we conclude that policies should be stable and consistent within a long‐term vision. An overall sustainability assurance framework of biomass production and use is key, but should ultimately apply to all end uses of biomass. Furthermore, the mobilization of biomass should be supported, as well as commoditization, considering the large diversity of biomass. Side impacts of biomass use should be monitored. Reducing investors’ risk perception is crucial for future developments in the biobased economy, and a clear policy to phase out fossil fuels, e.g. through a carbon tax, needs to be implemented. The results of this research are of interest for policy makers when deciding on long‐term strategies concerning sustainable bioenergy markets. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd