Search

Converting wind energy into ammonia (WtA) has been recognized as a promising pathway to produce “green” ammonia compared with traditional coal-based technologies. As the key part of WtA, Power-to-Ammonia (PtA) has great potential to facilitate the usage of wind generation. This paper proposes a co-planning approach for regional wind resources-based ammonia industry and the electric network (EN). To this end, PtA is first modeled as a flexible power load of power systems with spatial and temporal constraints on hydrogen supply chains (HSC). Then a novel co-planning model of WtA and EN is established to optimize the WtA configuration and the EN expansion. An alternating direction method of multipliers (ADMM) based algorithm is introduced to effectively solve this model. Real data of Inner Mongolia Province in China is adopted to verify the effectiveness and significance of the proposed approach. It is shown that the siting and operation flexibility of PtA with HSC can reduce the expansion burden of EN. The co-planning of WtA and EN can significantly enhance wind power utilization and reduce total investment costs. Furthermore, feasibility analysis on WtA in comparison with coal-to-ammonia (CtA) and ultra-high voltage transmission (UHV) provides helpful guidelines for the realization of WtA. [ABSTRACT FROM AUTHOR]

Recent developments in cryogenic electron microscopy (cryo‐EM) have enabled structural studies of large macromolecular complexes at resolutions previously only attainable using macromolecular crystallography. Although a number of methods can already assist in de novo building of models into high‐resolution cryo‐EM maps, automated and reliable map interpretation remains a challenge. Presented here is a systematic study of the accuracy of models built into cryo‐EM maps using ARP/wARP. It is demonstrated that the local resolution is a good indicator of map interpretability, and for the majority of the test cases ARP/wARP correctly builds 90% of main‐chain fragments in regions where the local resolution is 4.0 Å or better. It is also demonstrated that the coordinate accuracy for models built into cryo‐EM maps is comparable to that of X‐ray crystallographic models at similar local cryo‐EM and crystallographic resolutions. The model accuracy also correlates with the refined atomic displacement parameters. [ABSTRACT FROM AUTHOR]

The science of X‐ray free‐electron lasers (XFELs) critically depends on the performance of the X‐ray laser and on the quality of the samples placed into the X‐ray beam. The stability of biological samples is limited and key biomolecular transformations occur on short timescales. Experiments in biology require a support laboratory in the immediate vicinity of the beamlines. The XBI BioLab of the European XFEL (XBI denotes XFEL Biology Infrastructure) is an integrated user facility connected to the beamlines for supporting a wide range of biological experiments. The laboratory was financed and built by a collaboration between the European XFEL and the XBI User Consortium, whose members come from Finland, Germany, the Slovak Republic, Sweden and the USA, with observers from Denmark and the Russian Federation. Arranged around a central wet laboratory, the XBI BioLab provides facilities for sample preparation and scoring, laboratories for growing prokaryotic and eukaryotic cells, a Bio Safety Level 2 laboratory, sample purification and characterization facilities, a crystallization laboratory, an anaerobic laboratory, an aerosol laboratory, a vacuum laboratory for injector tests, and laboratories for optical microscopy, atomic force microscopy and electron microscopy. Here, an overview of the XBI facility is given and some of the results of the first user experiments are highlighted. [ABSTRACT FROM AUTHOR]

Abstract Background Docking algorithms are developed to predict in which orientation two proteins are likely to bind under natural conditions. The currently used methods usually consist of a sampling step followed by a scoring step. We developed a weighted geometric correlation based on optimised atom specific weighting factors and combined them with our previously published amino acid specific scoring and with a comprehensive SVM-based scoring function. Results The scoring with the atom specific weighting factors yields better results than the amino acid specific scoring. In combination with SVM-based scoring functions the percentage of complexes for which a near native structure can be predicted within the top 100 ranks increased from 14% with the geometric scoring to 54% with the combination of all scoring functions. Especially for the enzyme-inhibitor complexes the results of the ranking are excellent. For half of these complexes a near-native structure can be predicted within the first 10 proposed structures and for more than 86% of all enzyme-inhibitor complexes within the first 50 predicted structures. Conclusion We were able to develop a combination of different scoring schemes which considers a series of previously described and some new scoring criteria yielding a remarkable improvement of prediction quality.

Abstract Background One of the most challenging aspects of protein-protein docking is the inclusion of flexibility into the docking procedure. We developed a postfilter where the grid-representation of proteins for docking is extended by an optimised weighting factor for each amino acid. Results For up to 86% of the evaluated complexes a near-native structure was within the top 5% of the ranked prediction output. The weighting factors obtained by the optimisation procedure correlate to a certain extent with the flexibility of the amino acids, their hydrophobicity and with their propensity to be in the interface. Conclusion Use of the optimised amino acid specific parameters yields a strong increase of near-native structures on the first ranks of the prediction.

The performance of automated protein model building usually decreases with resolution, mainly owing to the lower information content of the experimental data. This calls for a more elaborate use of the available structural information about macromolecules. Here, a new method is presented that uses structural homologues to improve the quality of protein models automatically constructed using ARP/wARP. The method uses local structural similarity between deposited models and the model being built, and results in longer main‐chain fragments that in turn can be more reliably docked to the protein sequence. The application of the homology‐based model extension method to the example of a CFA synthase at 2.7 Å resolution resulted in a more complete model with almost all of the residues correctly built and docked to the sequence. The method was also evaluated on 1493 molecular‐replacement solutions at a resolution of 4.0 Å and better that were submitted to the ARP/wARP web service for model building. A significant improvement in the completeness and sequence coverage of the built models has been observed. [ABSTRACT FROM AUTHOR]

With regard to the Fukushima Daiichi accident in 2011 and Japan's goal to reduce CO 2 emission, the Japanese government strives for an emission free "hydrogen society" in which hydrogen will be the primary energy medium. The import of hydrogen generated by means of CO 2 free wind electricity from overseas can be a promising option for Japan's prospective energy supply. Besides different other factors like specific costs of electrolyzers and hydrogen shipment over long distances, the economically reasonable export of hydrogen based on renewable energy requires low levelized costs of electricity. Within the scope of this study, the underlying idea of a hydrogen supply chain is taken up and revisited by means of a spatially highly resolved wind energy potential analysis and a detailed investigation of the supply chain elements between Patagonia and Japan. Our analysis reveals that approximately 25% of the total land area in Patagonia would be eligible. Approx. 33,000 turbines with a minimum number of 4500 full-load hours with an overall capacity of about 115 GW can be positioned. Taking into consideration the related average number of 4750 full-load hours and an electrolysis efficiency of 0.7, this leads to a potential production of about 11.5 million tons/year of hydrogen. So the wind power potential of Patagonia would theoretically be sufficient for the assumed Japanese hydrogen demand of 8.83 million tons/year. The total hydrogen pretax cost would amount to approx. 4.40 €/kg H2 at a liquid state at the harbor of Yokohama. Hence, the final specific costs of hydrogen in Japan depend on the expansion of wind power in Patagonia and therefore hydrogen based on wind energy can be cost-competitive to conventional fuels. • Wind potential in Patagonia sufficient to cover prospective Japanese hydrogen demand. • Patagonian hydrogen from wind energy can be economically competitive to conventional fuels. • Largest supply chain costs shares contributed by electricity and ship transport. [ABSTRACT FROM AUTHOR]

A novel approach to obtaining structural information from macromolecular X-ray data extending to resolutions as low as 20 Å is presented. Following a simple map-segmentation procedure, the approximate shapes of the domains forming the structure are identified. A pattern-recognition comparative analysis of these shapes and those derived from the structures of domains from the PDB results in candidate structural models that can be used for a fit into the density map. It is shown that the placed candidate models can be employed for subsequent phase extension to higher resolution. [ABSTRACT FROM AUTHOR]

Background: Docking algorithms are developed to predict in which orientation two proteins are likely to bind under natural conditions. The currently used methods usually consist of a sampling step followed by a scoring step. We developed a weighted geometric correlation based on optimised atom specific weighting factors and combined them with our previously published amino acid specific scoring and with a comprehensive SVM-based scoring function. Results: The scoring with the atom specific weighting factors yields better results than the amino acid specific scoring. In combination with SVM-based scoring functions the percentage of complexes for which a near native structure can be predicted within the top 100 ranks increased from 14% with the geometric scoring to 54% with the combination of all scoring functions. Especially for the enzyme-inhibitor complexes the results of the ranking are excellent. For half of these complexes a near-native structure can be predicted within the first 10 proposed structures and for more than 86% of all enzyme-inhibitor complexes within the first 50 predicted structures. Conclusion: We were able to develop a combination of different scoring schemes which considers a series of previously described and some new scoring criteria yielding a remarkable improvement of prediction quality. [ABSTRACT FROM AUTHOR]

Background: One of the most challenging aspects of protein-protein docking is the inclusion of flexibility into the docking procedure. We developed a postfilter where the grid-representation of proteins for docking is extended by an optimised weighting factor for each amino acid. Results: For up to 86% of the evaluated complexes a near-native structure was within the top 5% of the ranked prediction output. The weighting factors obtained by the optimisation procedure correlate to a certain extent with the flexibility of the amino acids, their hydrophobicity and with their propensity to be in the interface. Conclusion: Use of the optimised amino acid specific parameters yields a strong increase of near-native structures on the first ranks of the prediction. [ABSTRACT FROM AUTHOR]

Copyright of Proteins is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)