On the physics behind coastal morphodynamic patterns

Peer ReviewedPostprint (published version

Revision of the EU Green Public Procurement (GPP) Criteria for Textile Products and Services: Technical Report with final criteria.

The revision of the Green Public Procurement (GPP) criteria for Textile products and Services is aimed at helping public authorities to ensure that textiles products and services are procured in such a way that it delivers environmental improvements that contribute to European policy objectives for energy, chemical management and resource efficiency, as well as reducing life cycle costs. In order to identify the most significant improvement areas for criteria development an analysis has been carried out of the environmental impacts of manufacturing and using textile products and providing textile services. The most commonly used procurement processes have been also identified and are further addressed in the separate criteria document (published as a Staff Working Document of the Commission). Together these two documents aim to provide public authorities with orientation on how to effectively integrate these GPP criteria into their procurement processes.JRC.B.5-Circular Economy and Industrial Leadershi

Field observations of shear waves in the surf zone

Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 109 (2004): C01031, doi:10.1029/2002JC001761.Alongshore propagating meanders of the mean alongshore current in the surf zone called shear waves have periods of a few minutes and wavelengths of a few hundred meters. Here shear wave properties are estimated with arrays of current meters deployed for 4 months within 300 m of the shoreline of a sandy beach. Shear wave velocity fluctuations are approximately horizontally isotropic, with root mean square values between 10 and 40% of the mean (3-hour-averaged) alongshore current V. Cross-shore variations of the time-averaged shear wave momentum flux are consistent with shear wave energy generation close to shore where the breaking wave-driven mean alongshore current V and current shear Vx are strong and with shear wave energy dissipation and transfer back to the mean flow farther offshore where V and Vx are weak. In case studies where V is a narrow jet near the shoreline the observed strong decay of shear wave energy levels seaward of the jet, and the cross-shore and alongshore structure of shear waves within the jet, are similar to predictions based on the linearly unstable modes of the observed V. Shear wave energy levels also are high in a marginally unstable case with a strong, but weakly sheared, V.This research was supported by the Office of Naval Research, the National Ocean Partnership Program and the National Science Foundation

Identifying macro-objectives for the life cycle environmental performance and resource efficiency of EU buildings

This working paper forms the main deliverable and outcome from work package A of the wider study. The aim of this working paper is to inform the identification of the most relevant macro-objectives for a building’s life cycle resource efficiency. These macro-objectives will in turn inform and set the scope for the common framework of indicators in work packages B,C and D. The first draft of this working paper was presented as the basis for discussion at the first stakeholder working group meeting, which was held in Brussels on the 16th June 2015. At that meeting the proposed boundaries, scope and coverage of the macro-objectives were discussed. Feedback from those discussions, together with follow-up written feedback, has been used in Chapters 6 and 7 of this working paper to identify a final set of macro-objectives that will be used to set the scope for the framework of indicators. In order to inform the initial proposals for discussion that were presented to stakeholders, this paper reviews existing legislation, scientific evidence, building schemes, collaborative research projects and other relevant literature. A high level scoping of environmental and resource efficiency ‘hot spots’ along the life cycle of buildings has also been carried out. Potential linkages and trade-offs between resource use, impacts along the life cycle and functional performance, with a specific focus on health and wellbeing aspects, have also been identified.JRC.B.5-Circular Economy and Industrial Leadershi

Influence of Amino Acid Substitutions in the Nisin Leader Peptide on Biosynthesis and Secretion of Nisin by Lactococcus lactis

Structural genes for small lanthionine-containing antimicrobial peptides, known as lantibiotics, encode N-terminal leader sequences which are not present in the mature peptide, but are cleaved off at some stage in the maturation process. Leader sequences of the different lantibiotics share a number of identical amino acid residues, but they are clearly different from sec-dependent protein export signal sequences. We studied the role of the leader sequence of the lantibiotic nisin, which is produced and secreted by Lactococcus lactis, by creating site-directed mutations at various positions in the leader peptide sequence. Mutations at Arg-1 and Ala-4, but not at the conserved Pro-2, strongly affected the processing of the leader sequence and resulted in the extracellular accumulation of a biologically inactive precursor peptide. Amino acid analysis and 1H NMR studies indicated that the precursor peptide with an Ala-4 → Asp mutation contained a modified nisin structural part with the (mutated) unmodified leader sequence still attached to it. The Ala-4 → Asp precursor peptide could be activated in vitro by enzymatic cleavage with trypsin, liberating nisin. These results confirmed that cleavage of the leader peptide is the last step in nisin maturation and is necessary to generate a biologically active peptide. Several mutations, i.e. Pro-2 → Gly, Pro-2 → Val, Asp-7 → Ala, Lys-9 → Leu, Ser-10 → Ala/Ser-12 → Ala and Val-11 → Asp/Val-13 → Glu in the leader peptide did not have any detectable effect on nisin production and secretion, although some of them affected highly conserved residues. When mutations were created in the -18 to -15 region of the nisin leader peptide (i.e. Phe-18 → Leu, Leu-16 → Lys, Asp-15 → Ala), no secretion or intracellular accumulation could be detected of nisin or its precursors. This suggested that these conserved residues are involved in the maturation process and may interact with lantibiotic-specific modifying enzymes.

The Expansion in Width for Domain Walls in Nematic Liquid Crystals in External Magnetic Field

The improved expansion in width is applied to curved domain walls in uniaxial nematic liquid crystals in external magnetic field. In the present paper we concentrate on the case of equal elastic constants. We obtain approximate form of the director field up to second order in magnetic coherence length.Comment: 18 pages, Latex 2.09, no figure

Physiological response of post-veraison deficit irrigation strategies and growth patterns of table grapes (cv. Crimson Seedless)

To determine whether partial root-zone drying (PRD) offers physiological advantages compared with regulated deficit irrigation (RDI), a 3 year long-experiment was conducted on a commercial vineyard of ‘Crimson Seedless’ table grapes (Vitis vinifera L.). Four different drip irrigation treatments were imposed: (i) a Control treatment irrigated at 110% of seasonal crop evapotranspiration (ETc), (ii), a regulated deficit irrigation (RDI) treatment irrigated similar to Control before veraison and at 50% of the Control treatment post-veraison, (iii) a partial root-zone drying (PRD) irrigated similar to RDI but alternating (every 10–14 days) the dry and wet side of the root-zone, and (iv) a null irrigation treatment (NI) which only received the natural precipitation and occasional supplementary irrigation when midday stem water potential (Ψs) dropped below −1.2 MPa. Post-veraison, PRD vines accumulated greater localized soil and plant water deficit at midday than RDI vines, but maintained similar pre-dawn water potential (Ψpd) values. Stomatal conductance (gs) of PRD vines remained high, likely because there was sufficient root water uptake from irrigated soil. Xylem ABA concentration ([ABA]xylem) did not change yet intrinsic WUE (WUEi) decreased compared to RDI vines, probably because PRD induced greater root density and root development at depth, allowing greater water uptake from roots in the wet part of the soil profile. Vegetative growth was only decreased by severe deficit irrigation (NI) although total leaf area index (LAI) was also affected by PRD in the 1st and 3rd year.. PRD can be considered a useful strategy in semiarid areas with limited water resources because sustained water use maintained assimilation rates despite greater stress than conventional RDI strategy, which may be related to root and morphological adjustment

Understanding coastal morphodynamic patterns from depth-averaged sediment concentration

This review highlights the important role of the depth-averaged sediment concentration (DASC) to understand the formation of a number of coastal morphodynamic features that have an alongshore rhythmic pattern: beach cusps, surf zone transverse and crescentic bars, and shoreface-connected sand ridges. We present a formulation and methodology, based on the knowledge of the DASC (which equals the sediment load divided by the water depth), that has been successfully used to understand the characteristics of these features. These sand bodies, relevant for coastal engineering and other disciplines, are located in different parts of the coastal zone and are characterized by different spatial and temporal scales, but the same technique can be used to understand them. Since the sand bodies occur in the presence of depth-averaged currents, the sediment transport approximately equals a sediment load times the current. Moreover, it is assumed that waves essentially mobilize the sediment, and the current increases this mobilization and advects the sediment. In such conditions, knowing the spatial distribution of the DASC and the depth-averaged currents induced by the forcing (waves, wind, and pressure gradients) over the patterns allows inferring the convergence/divergence of sediment transport. Deposition (erosion) occurs where the current flows from areas of high to low (low to high) values of DASC. The formulation and methodology are especially useful to understand the positive feedback mechanisms between flow and morphology leading to the formation of those morphological features, but the physical mechanisms for their migration, their finite-amplitude behavior and their decay can also be explored

Matching numerical simulations to continuum field theories: A lattice renormalization study

The study of nonlinear phenomena in systems with many degrees of freedom often relies on complex numerical simulations. In trying to model realistic situations, these systems may be coupled to an external environment which drives their dynamics. For nonlinear field theories coupled to thermal (or quantum) baths, discrete lattice formulations must be dealt with extreme care if the results of the simulations are to be interpreted in the continuum limit. Using techniques from renormalization theory, a self-consistent method is presented to match lattice results to continuum models. As an application, symmetry restoration in $\phi^4$ models is investigated.Comment: 15 pages RevTex, 12 postscript figure