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201.
Biogas is in many respects a serious alternative to other fossil resources and complements other renewable energy sources from wind and sun. Biogas can be produced in many places decentrally. Its energy potential is high, and it is widely used in the EU and all over the world. With more than 16,000 ktoe of oil equivalent in the EU in 2016, it corresponds to approximately 8% of the total primary energy produced by renewable energies in the EU, produced with nearly 17,000 biogas plants. Nevertheless, the production costs of biogas and its products like energy, heat, and fuel are still too high. Kost et al. (2018) show a comparison of electricity generation costs of different renewable energies and their future potentials. While electricity from huge biogas plants offers generation costs from 10 to 15 ct/kWh, electricity from onshore wind and huge solar systems offers generation costs from 4 to 8 ct/kWh. Although substantial progress has been made with regard to substrate use, production techniques and market designs, many more innovations are needed throughout the biogas value chain for it to be competitive in energy markets without high subsidies. As several papers in the special issue on biogas show, there are numerous innovations and product designs with regard to energy and material uses that could maintain or even increase the importance of biogas production both within and outside of the EU. There are many potential benefits of biogas, as it offers high shares of produced renewable energies as well as large amounts of material products like digestates and in future maybe products of higher value such as proteins or lactic acids. 相似文献
202.
Eckart Petig Hyung Sik Choi Elisabeth Angenendt Pascal Kremer Harald Grethe Enno Bahrs 《Global Change Biology Bioenergy》2019,11(10):1102-1124
The expansion of the bioeconomy sector will increase the competition for agricultural land regarding biomass production. Furthermore, the particular path of the expansion of the bioeconomy is associated with great uncertainty due to the early stage of technology development and its dependency on political framework conditions. Economic models are suitable tools to identify trade‐offs in agricultural production and address the high uncertainty of the bioeconomy expansion. We present results from the farm model Economic Farm Emission Model of four bioeconomy scenarios in order to evaluate impacts and trade‐offs of different potential bioeconomy developments and the corresponding uncertainty at regional and farm level in Baden‐Wuerttemberg, Germany. The demand‐side effects of the bioeconomy scenarios are based on downscaling European Union level results of a separate model linkage between an agricultural sector and an energy sector model. The general model results show that the expanded use of agricultural land for the bioeconomy sector, especially for the cultivation of perennial biomass crops (PBC), reduces biomass production for established value chains, especially for food and feed. The results also show differences between regions and farm types in Baden‐Wuerttemberg. Fertile arable regions and arable farms profit more from the expanded use of biomass in the bioeconomy than farms that focus on cattle farming. Latter farms use the arable land to produce feed for the cattle, whereas arable farms can expand feedstock production for new value chains. Additionally, less intensive production systems like extensive grassland suffer from economic losses, whereas the competition in fertile regions further increases. Hence, if the extensive production systems are to be preserved, appropriate subsidies must be provided. This emphasizes the relevance of downscaling aggregated model results to higher spatial resolution, even as far as to the decision maker (farm), to identify possible contradicting effects of the bioeconomy as well as policy implications. 相似文献
203.
Cationic amphipathic peptides, derived from bovine and human lactoferrins, with antimicrobial activity against oral pathogens 总被引:4,自引:0,他引:4
Jasper Groeninka Els Walgreen-Weteringsa Wim van 't Hofa Enno C.I Veermana Arie V Nieuw Amerongena 《FEMS microbiology letters》1999,179(2):217-222
Peptides derived from the N-terminal domain that comprises an amphipathic alpha-helix in human lactoferrin (LFh 18-31 and LFh 20-38) and bovine lactoferrin (LFb 17-30 and LFb 19-37) were chemically synthesised. Since many positively charged amphipathic alpha-helices contain antimicrobial activity, the peptides were tested for their antimicrobial activity against various oral pathogens. Both peptides from bovine lactoferrin had more potent antimicrobial activities than the human equivalents. Peptide LFb 17-30, containing the largest number of positively charged amino acids, showed the highest antimicrobial activity to both Gram-positive and Gram-negative bacteria. Since native lactoferrin molecules had no killing activity, release of these peptides from the native protein should be investigated to explore the use in oral care products. 相似文献
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206.
Most simple neuron models are only able to model traditional spiking behavior. As physiologists discover and classify different electrical phenotypes, computational neuroscientists become interested in using simple phenomenological models that can exhibit these different types of spiking patterns. The Hindmarsh–Rose model is a three-dimensional relaxation oscillator which can show both spiking and bursting patterns and has a chaotic regime. We test the predictive powers of the Hindmarsh–Rose model on two different test databases. We show that the Hindmarsh–Rose model can predict the spiking response of rat layer 5 neocortical pyramidal neurons on a stochastic input signal with a precision comparable to the best known spiking models. We also show that the Hindmarsh–Rose model can capture qualitatively the electrical footprints in a database of different types of neocortical interneurons. When the model parameters are fit from sub-threshold measurements only, the model still captures well the electrical phenotype, which suggests that the sub-threshold signals contain information about the firing patterns of the different neurons. 相似文献
207.
Alexandre da S. Conceição Adri Van Vliet Enno Krebbers 《Plant molecular biology》1994,26(3):1001-1005
In wild-type Arabidopsis seeds the 2S albumin seed protein gene family members are differentially expressed. In this work it is shown that as predicted by the wild type situation, the at2S2 promoter is much more effective than that of the at2S1 gene in the expression of a transgene. However, unexpectedly high expression levels were obtained using a construct in which the transgene was present as a tandem duplication in the T-DNA. Neither in this case nor in homozygous plants with either construct was epigenetic silencing observed. While transgene mRNA levels were of the same order of magnitude as the endogenous at 2S2 gene, protein levels were much lower. 相似文献
208.
Christian Hundsrucker Philipp Skroblin Frank Christian Hans-Michael Zenn Viola Popara Mangesh Joshi Jenny Eichhorst Burkhard Wiesner Friedrich W. Herberg Bernd Reif Walter Rosenthal Enno Klussmann 《The Journal of biological chemistry》2010,285(8):5507-5521
A-kinase anchoring proteins (AKAPs) include a family of scaffolding proteins that target protein kinase A (PKA) and other signaling proteins to cellular compartments and thereby confine the activities of the associated proteins to distinct regions within cells. AKAPs bind PKA directly. The interaction is mediated by the dimerization and docking domain of regulatory subunits of PKA and the PKA-binding domain of AKAPs. Analysis of the interactions between the dimerization and docking domain and various PKA-binding domains yielded a generalized motif allowing the identification of AKAPs. Our bioinformatics and peptide array screening approaches based on this signature motif identified GSKIP (glycogen synthase kinase 3β interaction protein) as an AKAP. GSKIP directly interacts with PKA and GSK3β (glycogen synthase kinase 3β). It is widely expressed and facilitates phosphorylation and thus inactivation of GSK3β by PKA. GSKIP contains the evolutionarily conserved domain of unknown function 727. We show here that this domain of GSKIP and its vertebrate orthologues binds both PKA and GSK3β and thereby provides a mechanism for the integration of PKA and GSK3β signaling pathways. 相似文献
209.