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The Local Action Plan of the Castelló Urban Agenda
Get PDFPublisher Copyright: © 2024, Ministerio de Fomento. All rights reserved.Under the Spanish Urban Agenda developed by the Ministry of Transport, Mobility and Urban Agenda, the Castelló de la Plana City Council was chosen in 2021 as a pilot municipality to prepare its Local Action Plan for the Urban Agenda. Through this article, the process developed by the Castelló municipality to translate the methodology developed at the national level to its local context is syn-thetically exposed, aiming to define its own Urban Agenda including the Local Action Plan as a strategic and operational instrument for municipal urban transformation.Peer reviewe
Ag@Fe3O4-coated U-shaped plastic optical fiber sensor for H2S detection
No full textPublisher Copyright: © 2023 Elsevier B.V.This work presents the fabrication of U-shaped plastic optical fiber (POF) sensors for hydrogen sulfide (H2S) detection, coated with Fe3O4 nanoparticles synthetized using the Pulsed Laser Ablation in Liquid (PLAL) technique. The Fe3O4 nanoparticles were synthetized in ultra-pure water and in silver nitrate solution, resulting in two colloidal samples with different morphological, optical, and structural properties. The Fe3O4 nanoparticles were coated onto one POF sensor, while the other sensor was coated with a nanostructure composed of Ag as the core and Fe3O4 as the shell (Ag@Fe3O4). The performance of both sensors was evaluated by exposing them to different concentrations of H2S and other gases such as CH4, H2, and CO2. All experiments were conducted at 25 °C. Results showed that the sensor coated with Ag@Fe3O4 was 12 times more sensitive to H2S compared to the sensor coated with Fe3O4, with a detection limit of 1 ppm and a rise time of 15 s. Moreover, the POF sensor coated with Ag@Fe3O4 presented high selectivity to H2S, making it a promising candidate for H2S detection in different applications. The sensor's performance was also evaluated with a relative humidity range of 20–90%, exhibiting a minimal 0.75% signal variation at 90% humidity.Peer reviewe
Conductivity monitoring of PBASE functionalized CVD graphene electrode for biosensor applications
No full textPublisher Copyright: © The Author(s), under exclusive licence to Springer Nature B.V. 2024.Graphene is extremely sensitive to its surrounding environment. In fact, any modification on its surface, such as an adsorption of a molecule, can change its properties. The conductivity of graphene is a crucial parameter to be examined for potential graphene-based applications, especially biosensors. In this paper, we have investigated the effects of non-covalent functionalization based on π–π interaction, using 1-pyrenebutyric acid N-hydroxysuccinimide ester (PBASE), on the conductivity of graphene-based electrodes by electrochemical techniques. Graphene layers were obtained by chemical vapor deposition (CVD) and characterized by Raman spectroscopy, Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). The results demonstrate the synthesis of a high quality and continuous monolayer graphene with an I2D/IG ratio = 2.71 and ID = 0. After the functionalization of graphene-based electrode with PBASE, the electrochemical analyses confirmed a p-doping effect existence influencing the conductivity by increasing the charge transfer resistance Rct from 816.5 to 2213 Ω. Furthermore, increasing the concentration of PBASE from 5 mM to 10 mM did not affect the conductivity as the Rct did not change. Solvent adsorption was found to be the main cause of the decrease in conductivity during the functionalization process. This study highlights the effect of non-covalent π-π stacking of PBASE on graphene to tune the electrical properties of graphene through functionalization processes for a better performance for their use as biosensors. Graphical abstract: (Figure presented.).Peer reviewe
Influence of chemistry and topography on the wettability of copper
No full textPublisher Copyright: © 2024 The Author(s)To understand the complex interplay of topography and surface chemistry in wetting, fundamental studies investigating both parameters are needed. Due to the sensitivity of wetting to miniscule changes in one of the parameters it is imperative to precisely control the experimental approach. A profound understanding of their influence on wetting facilitates a tailored design of surfaces with unique functionality. We present a multi-step study: The influence of surface chemistry is analyzed by determining the adsorption of volatile carbonous species (A) and by sputter deposition of metallic copper and copper oxides on flat copper substrates (B). A precise surface topography is created by laser processing. Isotropic topography is created by ps laser processing (C), and hierarchical anisotropic line patterns are produced by direct laser interference patterning (DLIP) with different pulse durations (D). Our results reveal that the long-term wetting response of polished copper surfaces stabilizes with time despite ongoing accumulation of hydrocarbons and is dominated by this adsorption layer over the oxide state of the substrate (Cu, CuO, Cu2O). The surfaces’ wetting response can be precisely tuned by tailoring the topography via laser processing. The sub-pattern morphology of primary line-like patterns showed great impact on the static contact angle, wetting anisotropy, and water adhesion. An increased roughness inside the pattern valleys combined with a minor roughness on pattern peaks favors air-inclusions, isotropic hydrophobicity, and low water adhesion. Increasing depth of the primary topography can also induce air-inclusions despite increasing peak roughness while time dependent wetting transitions were observed.Peer reviewe
Inertia emulation control of PMSG-based wind turbines for enhanced grid stability in low inertia power systems
No full textPublisher Copyright: © 2023 The Author(s)With increased penetration of the converter dominated renewables, the overall inertial response and frequency stability of the power grid has been reduced. Low inertia contributes to maximum frequency deviations with higher rate of change of frequency that undermines the reliability of the power system. In the case of type-4 grid connected wind turbines, the kinetic energy of the rotor cannot be directly used to mitigate frequency excursions in the AC grid since fully-rated converters decouple the grid from the turbine rotor. Nonetheless, by designing an adequate control system for full converters, emulated inertia of the rotor can be propagated to the grid. In this paper, we present inertia emulation control strategy based on second order differential equation analogous to the swing equation of classical synchronous machines employed in machine side converter of the permanent magnet synchronous generator wind turbines. The proposed control allows the management of virtual inertia, damping and reactance. The performance of the proposed controller is verified through time-domain simulations and eigenvalue analysis performed in MATLAB Simulink.This work is supported by the Swinburne University of Technology, Australia and Higher Education Commission of Pakistan under HRDI-UESTP Program.Peer reviewe
Identification of GB3 as a Novel Biomarker of Tumor-Derived Vasculature in Neuroblastoma Using a Stiffness-Based Model
No full textPublisher Copyright: © 2024 by the authors.Neuroblastoma (NB) is a childhood cancer in sympathetic nervous system cells. NB exhibits cellular heterogeneity, with adrenergic and mesenchymal states displaying distinct tumorigenic potentials. NB is highly vascularized, and blood vessels can form through various mechanisms, including endothelial transdifferentiation, leading to the development of tumor-derived endothelial cells (TECs) associated with chemoresistance. We lack specific biomarkers for TECs. Therefore, identifying new TEC biomarkers is vital for effective NB therapies. A stiffness-based platform simulating human arterial and venous stiffness was developed to study NB TECs in vitro. Adrenergic cells cultured on arterial-like stiffness transdifferentiated into TECs, while mesenchymal state cells did not. The TECs derived from adrenergic cells served as a model to explore new biomarkers, with a particular focus on GB3, a glycosphingolipid receptor implicated in angiogenesis, metastasis, and drug resistance. Notably, the TECs unequivocally expressed GB3, validating its novelty as a marker. To explore targeted therapeutic interventions, nanoparticles functionalized with the non-toxic subunit B of the Shiga toxin were generated, because they demonstrated a robust affinity for GB3-positive cells. Our results demonstrate the value of the stiffness-based platform as a predictive tool for assessing NB aggressiveness, the discovery of new biomarkers, and the evaluation of the effectiveness of targeted therapeutic strategies.Peer reviewe
Natural events and informal urban growth in coastal areas of Ecuador
No full textPublisher Copyright: © 2024 Universidad Nacional de Colombia. All rights reserved.Ecuador is a country susceptible and vulnerable to the threats of natural events, especially along its coastal profile. One-third of the total events recorded in Ecuador occur in the coastal margin provinces, with floods and landslides being the most frequently occurring events. Guayas, Manabí, and Esmeraldas are identified as the provinces in which the greatest number of events have been evidenced. Vulnerability to disaster threats increases if the equation includes the expansion of urban sprawl in risk areas characterized by limited access to basic services, precariousness, insecurity, and poverty. As a study objective, the main strategies adopted by Ecuador’s government to minimize both the effects derived from natural events and those generated by informal urban growth are presented. It is concluded that beyond any policy and strategy established by each government on the subject, civil society’s action and joint efforts are fundamental to establishing corrective measures, raising awareness, and modifying those habits contrary to the detriment of environmental deterioration.Peer reviewe
Understanding metric-related pitfalls in image analysis validation
No full textPublisher Copyright: © Springer Nature America, Inc. 2024.Validation metrics are key for tracking scientific progress and bridging the current chasm between artificial intelligence research and its translation into practice. However, increasing evidence shows that, particularly in image analysis, metrics are often chosen inadequately. Although taking into account the individual strengths, weaknesses and limitations of validation metrics is a critical prerequisite to making educated choices, the relevant knowledge is currently scattered and poorly accessible to individual researchers. Based on a multistage Delphi process conducted by a multidisciplinary expert consortium as well as extensive community feedback, the present work provides a reliable and comprehensive common point of access to information on pitfalls related to validation metrics in image analysis. Although focused on biomedical image analysis, the addressed pitfalls generalize across application domains and are categorized according to a newly created, domain-agnostic taxonomy. The work serves to enhance global comprehension of a key topic in image analysis validation.Peer reviewe
An investigation into the erosion and wear mechanisms observed in abradable ytterbium disilicate environmental barrier coatings
No full textPublisher Copyright: © 2024 The AuthorsAbradable environmental barrier coatings (EBCs) are used to reduce clearances between blades and casings in the hottest parts of aero gas turbines, increasing the overall efficiency of the turbine, however, research into the mechanical performance of such coatings is limited. The aim of this work was to better understand the relationship between microstructure and erosion and wear performance in abradable EBCs, since publicly available literature regarding such coatings is scarce and the potential efficiency gains in gas turbines are significant. In this study, ytterbium disilicate abradable EBCs containing three different porosity levels (determined by fugitive polyester phase addition) were deposited using atmospheric plasma spraying with porosity levels of 8, 15 and 21.5% by area. These coatings were then characterised in numerous ways; the porosity was quantified, the thermal conductivity was measured, the superficial hardness and erosion resistance were measured, and finally, the coatings were subjected to a rig test designed to simulate in-service cutting mechanisms against a tipped turbine blade. The results show that increasing the level of porosity via increasing the amount of pore forming phase in the feedstock, led to reduced erosion resistance and improved cutting by a turbine blade.Peer reviewe
Categorisation of urban open spaces for heat adaptation: A cluster based approach
No full textPublisher Copyright: © 2024 The AuthorsIn the context of climate change, adapting a city's open spaces to heat waves and extreme heat is crucial for mitigating the Urban Heat Island effect and ensuring the wellbeing of its inhabitants. However, the heat adaptation potential of open spaces varies within a city. This study develops an objective and replicable method to categorise urban areas based on their open spaces' adaptive capacity and improvement potential to heat waves at the micro-scale. This is achieved using a clustering approach, eliminating manual operations, using openly available data, employing indicators suitable for every urban fabric type, and using the urban block as the analysis unit. The validation of the method in the case study of Bilbao (Spain) demonstrates its capacity to obtain meaningful insights regarding open space heat adaptation potential. An analysis of the resulting categories reveals significant open space improvement potential throughout the city and a varying adaptive capacity that depends on urban density. Categories with the lowest adaptive capacity have median open space ratios between 0.35 and 0.65 and median tree cover ratios between 0.07 and 0.15. Those with the highest adaptive capacity present median open space ratios between 0.8 and 1 and median tree cover ratios between 0.05 and 0.25. The method can aid local policymakers in identifying opportunity spots for hosting adaptation solutions and understanding the challenges the city may face in planning adaptation action. The method's replicability enables it to be applied in other cities, contributing to a broader exploration of climate change adaptation potential.Peer reviewe