222 research outputs found
Coal and Petrochemical Soundscapes in North Bohemia: Some Personal Thoughts
The project 'Frontiers of Solitude' focuses on contemporary transformations of the landscape and the close connections between our post-industrial civilization and nature. These themes are elaborated in terms of the cultural geography and morphology of three selected areas of the Czech Republic, Iceland and Norway. This article is one of the contributions to the the project's final catalogue and represents my engagement with the fascinating lignite mining areas of North Bohemia in the Czech Republic
Field Recording as Sonic Journalism
What is sonic-journalism? In radio news, current affairs and sound documentary, as on TV despite the significance of images, the dominance of speech – spoken reportage, interviews, commentary, discussion – is unquestioned. Sonic–journalism is based on the idea that all sound, including non–speech, gives information about places and events and that listening provides valuable insights different from, but complimentary to, visual images and language. This does not exclude speech but re–addresses the balance towards the relevance of other sounds. In practice field recordings become the means to achieve this. Recordings can, of course, be used in many ways. In my view sonic–journalism occurs when field recordings are allowed adequate space and time to be heard in their own right
Action perception is intact in autism spectrum disorder
Date of Acceptance:10/11/2014. Copyright © 2015 the authors 0270-6474/15/351849-09$15.00/0. Copyright of all material published in The Journal of Neuroscience remains with the authors. The authors grant the Society for Neuroscience an exclusive license to publish their work for the first 6 months. After 6 months the work becomes available to the public to copy, distribute, or display under a Creative Commons Attribution 4.0 International (CC BY 4.0) license.Peer reviewedPublisher PD
Tuning of Calcite Crystallographic Orientation to Support Brachiopod Lophophore
Organisms exert exquisite control on mineral formation by tuning structural and material properties to meet functional requirements. Brachiopods are sessile marine organisms that filter feed via a large lophophore which is supported by a delicate calcite loop that grows from the inner surface of the shell. How does the loop support the weight of the large lophophore? Electron backscatter diffraction (EBSD) and nanoindentation analyses of the loop as it emerges from the shell of Laqueus rubellus reveal that calcite fiber crystallography generates asymmetry in the material properties of the structure. In the core of the emergent loop, the fibers are short and kernel‐like. Either side of the core, the long fibers have a different crystallographic orientation and resultant material properties. fibers on the anterior, load‐bearing side, are harder (H = 3.76 ± 0.24 GPa) and less stiff (E = 76.87 ± 4.87 GPa) than the posterior (H = 3.48 ± 0.31 GPa, E = 81.79 ± 5.33 GPa). As a consequence of the asymmetry in the material properties, the loop anterior may be more flexible under load. The brachiopod strategy of tuning crystallographic orientation to confer spatially determined material properties is attractive for additive manufacturing of synthetic materials that have complex heterogeneous material property requirements
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OPP Implementation in the WCPO
The tuna catch from the Western and Central Pacific Ocean (WCPO) amounted to 2.86 m mt in 2014, worth USD5.8 b and accounting for about 60% of the global tuna catch. About 60% of the catch was taken in the waters of the Pacific Island Forum Fisheries Agency (FFA) member-countries and territories, about one third of the global catch by volume. The three main fish stocks of skipjack, yellowfin and albacore, accounting for 95% of the catch are ‘biologically healthy’. However, bigeye tuna is overfished and albacore longline fishing, particularly by domestic fleets, is uneconomic. Although there is little scope to increase catches, the economic benefits of the fishery to resource owners have increased dramatically in recent times, through access fees, domestication of fleets, onshore processing and export revenues, but only 30% of fish caught in FFA-member waters is taken by local fleets and only 15% is landed for processing. To increase and maintain benefits, Pacific Island countries seek to raise their level of participation in the value chain, but are constrained by challenges in market access, lack of infrastructure, transport and utility costs, low labor productivity and often weak Government investment frameworks. FFA’s implementation of OPP in the region is developing a pipeline of business opportunities, including scoping of a sub-regional FAD management scheme, exploring PPP models for financing the development of a dedicated tuna port in Papua New Guinea, and “investment ready” support for establishment of a purse-seine vessel service centre at a major transhipping port.
Crystallographic Interdigitation in Oyster Shell Folia Enhances Material Strength
Shells of oyster species belonging to the genus Crassostrea have similar shell microstructural features comprising well-ordered calcite folia. However, the mechanical strengths of folia differ dramatically between closely related species. For example, the calcareous shells of the Hong Kong oyster Crassostrea hongkongensis are stronger than those of its closest relative, the Portuguese oyster, Crassostrea angulata. Specifically, after removal of organic content, the folia of C. hongkongensis are 200% tougher and able to withstand a 100% higher crushing force than that of C. angulata. Detailed analyses of shell structural and mechanical features support the hypothesis that crystallographic interdigitations confer elevated mechanical strength in C. hongkongensis oyster shells compared to C. angulata shells. Consequently, the folia of C. hongkongensis are structurally equipped to withstand a higher external load compared to C. angulata. The observed relationships between oyster shell structure, crystallography, and mechanical properties provided an insightful context in which to consider the likely fate of these two species in future climate change scenarios. Furthermore, the interdisciplinary approach developed in this study through integrating electron backscatter diffraction (EBSD) data into finite element analysis (FEA) could be applied to other biomineral systems to investigate the relationship between crystallography and mechanical behavior
Biomineral repair of Abalone shell apertures
The shell of the gastropod mollusc, abalone, is comprised of nacre with an outer prismatic layer that is composed of either calcite or aragonite or both, depending on the species. A striking characteristic of the abalone shell is the row of apertures along the dorsal margin. As the organism and shell grow, new apertures are formed and the preceding ones are filled in. Detailed investigations, using electron backscatter diffraction, of the infill in three species of abalone: Haliotis asinina, Haliotis gigantea and Haliotis rufescens reveals that, like the shell, the infill is composed mainly of nacre with an outer prismatic layer. The infill prismatic layer has identical mineralogy as the original shell prismatic layer. In H. asinina and H. gigantea, the prismatic layer of the shell and infill are made of aragonite while in H. rufescens both are composed of calcite. Abalone builds the infill material with the same high level of biological control, replicating the structure, mineralogy and crystallographic orientation as for the shell. The infill of abalone apertures presents us with insight into what is, effectively, shell repair
Enabling effective operational decision making on a Combined Heat and Power System using the 5C architecture
The use of Cyber Physical Systems (CPS) to optimise industrial energy systems is an approach which has the potential to positively impact on manufacturing sector energy efficiency. The need to obtain data to facilitate the implementation of a CPS in an industrial energy system is however a complex task which is often implemented in a non-standardised way. The use of the 5C CPS architecture has the potential to standardise this approach. This paper describes a case study where data from a Combined Heat and Power (CHP) system located in a large manufacturing company was fused with grid electricity and gas models as well as a maintenance cost model using the 5C architecture with a view to making effective decisions on its cost efficient operation. A control change implemented based on the cognitive analysis enabled via the 5C architecture implementation has resulted in energy cost savings of over €7400 over a four-month period, with energy cost savings of over €150,000 projected once the 5C architecture is extended into the production environment
The structural basis for seryl-adenylate and Ap4A synthesis by seryl-tRNA synthetase
AbstractBackground: Seryl-tRNA synthetase is a homodimeric class II aminoacyl-tRNA synthetase that specifically charges cognate tRNAs with serine. In the first step of this two-step reaction, Mg·ATP and serine react to form the activated intermediate, seryl-adenylate. The serine is subsequently transferred to the 3′-end of the tRNA. In common with most other aminoacyl-tRNA synthetases, seryl-tRNA synthetase is capable of synthesizing diadenosine tetraphosphate (Ap4A) from the enzyme-bound adenylate intermediate and a second molecule of ATP. Understanding the structural basis for the substrate specificity and the catalytic mechanism of aminoacyl-tRNA synthetases is of considerable general interest because of the fundamental importance of these enzymes to protein biosynthesis in all living cells.Results Crystal structures of three complexes of seryl-tRNA synthetase from Thermus thermophilus are described. The first complex is of the enzyme with ATP and Mn2+. The ATP is found in an unusual bent conformation, stabilized by interactions with conserved arginines and three manganese ions. The second complex contains seryl-adenylate in the active site, enzymatically produced in the crystal after soaking with ATP, serine and Mn2+. The third complex is between the enzyme, Ap4A and Mn2+. All three structures exhibit a common Mn2+ site in which the cation is coordinated by two active-site residues in addition to the α-phosphate group from the bound ligands.Conclusion Superposition of these structures allows a common reaction mechanism for seryl-adenylate and Ap4A formation to be proposed. The bent conformation of the ATP and the position of the serine are consistent with nucleophilic attack of the serine carboxyl group on the α-phosphate by an in-line displacement mechanism leading to the release of the inorganic pyrophosphate. A second ATP molecule can bind with its γ-phosphate group in the same position as the β-phosphate of the original ATP. This can attack the seryl-adenylate with the formation of Ap4A by an identical in-line mechanism in the reverse direction. The divalent cation is essential for both reactions and may be directly involved in stabilizing the transition state
Biomineral shell formation under ocean acidification: A shift from order to chaos
Biomineral production in marine organisms employs transient phases of amorphous calcium carbonate (ACC) in the construction of crystalline shells. Increasing seawater pCO2 leads to ocean acidification (OA) with a reduction in oceanic carbonate concentration which could have a negative impact on shell formation and therefore survival. We demonstrate significant changes in the hydrated and dehydrated forms of ACC in the aragonite and calcite layers of Mytilus edulis shells cultured under acidification conditions (1000 μatm pCO2) compared to present day conditions (380 μatm pCO2). In OA conditions, Mytilus edulis has more ACC at crystalisation sites. Here, we use the high-spatial resolution of synchrotron X-ray Photo Emission Electron Microscopy (XPEEM) combined with X-ray Absorption Spectroscopy (XAS) to investigate the influence of OA on the ACC formation in the shells of adult Mytilus edulis. Electron Backscatter Diffraction (EBSD) confirms that OA reduces crystallographic control of shell formation. The results demonstrate that OA induces more ACC formation and less crystallographic control in mussels suggesting that ACC is used as a repair mechanism to combat shell damage under OA. However, the resultant reduced crystallographic control in mussels raises concerns for shell protective function under predation and changing environments. © 2016, Nature Publishing Group. All rights reserved
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