The structural evolution of transtensional basins and rifted margins

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Super-Hydrophobic Multi-Walled Carbon Nanotube Coatings for Stainless Steel

We have taken advantage of the native surface roughness and the iron content of AISI 316 stainless steel to direct grow multi-walled carbon nanotube (MWCNT) random networks by chemical vapor deposition (CVD) at low-temperature ($< 1000^{\circ}$C), without the addition of any external catalysts or time-consuming pre-treatments. In this way, super-hydrophobic MWCNT films on stainless steel sheets were obtained, exhibiting high contact angle values ($154^{\circ}$) and high adhesion force (high contact angle hysteresis). Furthermore, the investigation of MWCNT films at scanning electron microscopy (SEM) reveals a two-fold hierarchical morphology of the MWCNT random networks made of hydrophilic carbonaceous nanostructures on the tip of hydrophobic MWCNTs. Owing to the Salvinia effect, the hydrophobic and hydrophilic composite surface of the MWCNT films supplies a stationary super-hydrophobic coating for conductive stainless steel. This biomimetical inspired surface not only may prevent corrosion and fouling but also could provide low-friction and drag-reduction.Comment: 6 pages, 3 figure

Exploiting the Hierarchical Morphology of Single-Walled and Multi-Walled Carbon Nanotube Films for Highly Hydrophobic Coatings

Self-assembled hierarchical solid surfaces are very interesting for wetting phenomena, as observed in a variety of natural and artificial surfaces. Here, we report single-walled (SWCNT) and multi-walled carbon nanotube (MWCNT) thin films realized by a simple, rapid, reproducible, and inexpensive filtration process from an aqueous dispersion, that was deposited at room temperature by a dry-transfer printing method on glass. Furthermore, the investigation of carbon nanotube films through scanning electron microscopy (SEM) reveals the multi-scale hierarchical morphology of the self-assembled carbon nanotube random networks. Moreover, contact angle measurements show that hierarchical SWCNT/MWCNT composite surfaces exhibit a higher hydrophobicity (contact angles of up to 137{\deg}) than bare SWCNT (110{\deg}) and MWCNT (97{\deg}) coatings, thereby confirming the enhancement produced by the surface hierarchical morphology.Comment: 7 pages, 5 figures, This article is part of the Thematic Series "Self-assembly of nanostructures and nanomaterials

Evaluating roughness scaling properties of natural active fault surfaces by means of multi-view photogrammetry

Fault roughness is a measure of the dimensions and distribution of fault asperities, which can act as stress concentrators affecting fault frictional behaviour and the dynamics of rupture propagation. Studies aimed at describing fault roughness require the acquisition of extremely detailed and accurate datasets of fault surface topography. Fault surface data have been acquired by methods such as LiDAR, laser profilometers and white light interferometers, each covering different length scales and with only LiDAR available in the field. Here we explore the potential use of multi-view photogrammetric methods in fault roughness studies, which are presently underexplored and offer the advantage of detailed data acquisition directly in the field. We applied the photogrammetric method to reproduce fault topography, by using seven dm-sized fault rock samples photographed in the lab, three fault surfaces photographed in the field, and one control object used to estimate the model error. We studied these topographies estimating their roughness scaling coefficients through a Fourier power spectrum method. Our results show scaling coefficients of 0.84 ± 0.17 along the slip direction and 0.91 ± 0.17 perpendicularly to it, and are thus comparable to those results obtained by previous authors. This provides encouragement for the use of photogrammetric methods for future studies, particularly those involving field-based acquisition, where other techniques have limitations

The Fe65 Adaptor Protein Interacts through Its PID1 Domain with the Transcription Factor CP2/LSF/LBP1

The neural protein Fe65 possesses three putative protein-protein interaction domains: one WW domain and two phosphotyrosine interaction/phosphotyrosine binding domains (PID1 and PID2); the most C-terminal of these domains (PID2) interacts in vivo with the Alzheimer's beta-amyloid precursor protein, whereas the WW domain binds to Mena, the mammalian homolog of Drosophila-enabled protein. By the interaction trap procedure, we isolated a cDNA clone encoding a possible ligand of the N-terminal PID/PTB domain of Fe65 (PID1). Sequence analysis of this clone revealed that this ligand corresponded to the previously identified transcription factor CP2/LSF/LBP1. Co-immunoprecipitation experiments demonstrated that the interaction between Fe65 and CP2/LSF/LBP1 also takes place in vivo between the native molecules. The localization of both proteins was studied using fractionated cellular extracts. These experiments demonstrated that the various isoforms of CP2/LSF/LBP1 are differently distributed among subcellular fractions. At least one isoform, derived from alternative splicing (LSF-ID), is present outside the nucleus; Fe65 was found in both fractions. Furthermore, transfection experiments with an HA-tagged CP2/LSF/LBP1 cDNA demonstrated that Fe65 interacts also with the nuclear form of CP2/LSF/LBP1. Considering that the analysis of Fe65 distribution in fractionated cell extracts demonstrated that this protein is present both in nuclear and non-nuclear fractions, we examined the expression of Fe65 deletion mutants in the two fractions. This analysis allowed us to observe that a small region N-terminal to the WW domain is phosphorylated and is necessary for the presence of Fe65 in the nuclear fraction

An Application of the Harmony-Search Multi-Objective (HSMO) Optimization Algorithm for the Solution of Pump Scheduling Problem☆

Abstract In hydraulic systems, water is often pumped to reach higher elevations, so as to ensure the minimum required pressure and guarantee adequate service level. However, pumps cannot be instantly activated and people do not consume the resource in uniform mode throughout the day. To avoid direct pumping, water can be stored in tanks at a higher elevation, so that it can be supplied whenever there is a higher demand. Because of the significant costs required for pumping, energy-saving in water supply systems is one of the most challenging issues to ensure optimal management of water systems. Careful scheduling of pumping operations may lead not only to energy savings, but alsoto prevent damages, as consequence of reduction of operation times and switches. By means of computer simulation, an optimal schedule of pumps can be achieved using optimization algorithms. In this paper, a harmony-search multi-objective (HSMO) optimization approach is adapted to the pump scheduling problem. The model interfaces with the popular hydraulic solver, EPANET 2.0, to check the hydraulic constraints and to evaluate the performances of the selected schedules. Penalties are introduced in the objective function in case of violation of the hydraulic constraints. The model is applied to a case study, showing that the results are comparable with those of competitive meta-heuristic algorithms (e.g. Genetic Algorithms) and pointing out the suitability of the HSMO algorithm for pumping optimization

Modelling Approach for NBSs Suitability Assessment in an Agricultural Area under Changing Climate Conditions: Case Studies in the Massaciuccoli Catchment (Central Italy)

Nature-Based Solutions (NBSs) are considered worldwide as a suitable approach for mitigating the impact of industrial agriculture on sediments and nutrient losses. However, their actual effectiveness is still questioned. In cases where site measurements of NBS performance are scarce, models can provide useful insights if accurately set. This study analyzed the effects of vegetated buffer strips (VBSs) and winter cover crops (WCCs) planted in some herbaceous cropping systems within the Massaciuccoli reclamation area (Vecchiano, Central Italy). Analyses stem from modelling water and soil dynamics by applying SWAT+ at field scale on high resolution close-range photogrammetric digital terrain model (DTM), real crop rotations, and a detailed calendar of the main agronomic interventions. The NBS implementation was modelled in two experimental areas, showing contrasting soil properties. Comparing results from the modelling of different scenarios highlighted that NBS mitigative effect is influenced by soil properties and local topographic irregularities, which could induce concentrated flows. Long term climate changes can induce relevant different effects by varying the nature of soil

Normal approximation of Random Gaussian Neural Networks

In this paper we provide explicit upper bounds on some distances between the (law of the) output of a random Gaussian NN and (the law of) a random Gaussian vector. Our results concern both shallow random Gaussian neural networks with univariate output and fully connected and deep random Gaussian neural networks, with a rather general activation function. The upper bounds show how the widths of the layers, the activation functions and other architecture parameters affect the Gaussian approximation of the ouput. Our techniques, relying on Stein's method and integration by parts formulas for the Gaussian law, yield estimates on distances which are indeed integral probability metrics, and include the total variation and the convex distances. These latter metrics are defined by testing against indicator functions of suitable measurable sets, and so allow for accurate estimates of the probability that the output is localized in some region of the space. Such estimates have a significant interest both from a practitioner's and a theorist's perspective

Lithological controls on the deformation mechanisms operating within carbonate-hosted faults during the seismic cycle

A significant proportion of moderate-large earthquakes, plus aftershocks, nucleate within and propagate through upper-crustal carbonate-dominated sequences, where the effects of lithological variations on fault behaviour are poorly understood. The Gubbio fault is an active (1984, Ms = 5.2) normal fault in Italy, hosted in Mesozoic–Cenozoic limestones and interbedded marls. Fault core domains derived from limestone at the studied outcrop are characterised by fractures/hydrofractures and breccias and host a number of localised (<1.5 mm wide) principal slip zones (PSZs). The majority of displacement of up to 230 m is concentrated in these PSZs, which comprise cataclasites, gouges, and calcite veins. Degassing bubbles, ‘quenched’ calcite, and the transformation of smectite to illite, are also observed within PSZs, implying frictional heating and seismic slip. In contrast, marl-rich domains exhibit distributed shear planes bounding a continuous and pervasive foliation, defined by phyllosilicate-rich pressure-solution seams. Microstructures in the seams include folds/kinks of phyllosilicates and pressure shadows around clasts, consistent with aseismic fault creep. A model is proposed for the behaviour of lithologically complex carbonate-hosted faults during the seismic cycle, whereby limestone-dominated fault core domains behave in a predominantly seismic manner, whereas phyllosilicate-rich domains behave in a predominantly aseismic manner