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Hemocompatible Coatings of Catheters Equipped with Electrochemical Sensors for Real-Time Monitoring of Critical Parameters in the Blood
No full textPublisher Copyright: © 2025 American Chemical Society.Continuous monitoring of blood parameters at the bedside is crucial for critically ill patients. Miniaturized biosensors integrated into medical devices in direct contact with blood can improve the quality of monitoring by reducing response time in emergencies as well as the invasiveness and blood consumption during the measurements. In such settings, coating biosensors with hemocompatible materials is essential for achieving biocompatibility and maximum acceptance of the devices for direct measurements of blood parameters in the human body. Here, we present an instrumented catheter equipped with a hemocompatible electrochemical sensor to continuously monitor one of the key parameters- glucose, lactate, and pH, directly in blood. Selective amperometric and potentiometric sensors were obtained by modifying the electrodes with enzymes and pH-responsive toluidine blue O. The glucose sensors exhibited a linear response from 0.06 to 10 mM with a sensitivity of −116 ± 16 nA/mMGlucose, while the lactate sensor had a linear response between 5 and 20 mM with a sensitivity of −38 ± 6 nA/mMLactate. A pH sensitivity of −20.17 ± 2.37 mV/pH for sensors with the hydrogel-covered TBO film has been reached. Hemocompatible properties, crucial for in vivo applications, were achieved by coating the functional electrode surfaces with an additional hydrogel layer based on a four-armed poly(ethylene glycol), cross-linked with the anticoagulant polysaccharide heparin. Initially, the functionalization strategy was thoroughly evaluated in terms of sensor response and hemocompatibility in a planar format; followed by a proof-of-principle demonstration of glucose sensing with a catheter imprinted with the respective electrochemical sensor.Peer reviewe
An Infrastructure-Based Localization Method for Articulated Vehicles
No full textPublisher Copyright: © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.Automating articulated vehicles in valet parking maneuvers is becoming more significant, due to the growing need for efficient freight transportation and logistics. Thus, this paper introduces a novel Infrastructure to Vehicle (I2V) localization approach for articulated vehicles. The proposed method focuses on accurately classifying trucks and trailers and hitch angle estimation between them. Validations with real-world LiDAR data on different articulated vehicles show that our solution improves safety and efficiency in automated docking scenarios without vehicle modifications.Peer reviewe
Plasma nitrided ferritic stainless steel surfaces as hydrogen permeation barriers
Full text linkPublisher Copyright: © 2025 The AuthorsHydrogen has the potential to replace fossil fuels in certain sectors where decarbonization presents significant challenges. However, components manufactured in metallic alloys that come into contact with hydrogen are susceptible to hydrogen induced embrittlement (HE) to varying degrees. Plasma based surface treatments might provide a barrier to hydrogen diffusion, a prerequisite for HE. This study aims at investigating the performance as hydrogen diffusion barrier of active screen plasma nitrided treatments on a ferritic stainless steel (X6Cr17). The research has focused on the nitriding parameters (mainly processing temperature), as well as the thickness and microstructure of the steel. A variety of techniques, including X-ray diffraction spectroscopy, microscopy, indentation and hydrogen permeation tests were employed throughout the study on different nitrided surfaces. The findings of the study indicate that plasma nitrided surfaces act as effective hydrogen permeation barriers. Results show a reduction of the hydrogen permeation flow by up to two orders of magnitude compared to the same untreated steel alloy (2.0 × 10−9 vs. 4.2 × 10−7 Pa.m3/s). This is accompanied by a delay in the hydrogen permeation uptake of >25 times compared to the same untreated steel alloy. However, the findings also indicate that the surface treatment effectiveness is influenced by both the presence of surface defects and the depths and microstructure of the nitrided surfaces.Peer reviewe
Sustainable Building Standards in the Galapagos Islands: Definition, Simulation, and Implementation in Representative Living Labs
Full text linkPublisher Copyright: © 2025 by the authors.The Galapagos Islands are undeniably a highly attractive ecosystem for scientists worldwide. However, the energy efficiency and sustainability aspects of their building stock have not yet been studied in depth, which directly hinders the achievement of sustainability goals for the Archipelago, such as reducing resource consumption, minimizing emissions, and improving overall comfort in buildings. Addressing these issues is critical to preserving the islands’ unique ecosystem, as current construction practices are unsustainable and exacerbate environmental pressures, causing over-consumption of local resources and upsetting the delicate ecological balance that sustains this fragile environment. In line with the National Energy Efficiency Plan promoted by the Government of Ecuador for the Archipelago, this study provides transparent and reliable information and data on the building stock of the islands. This work quantifies the impact of buildings on the use of resources and analyses the potential savings of different strategies for reducing greenhouse gas emissions. Various representative typologies are established based on the collection of architectural, construction, and usage information. For each of these typologies, various energy models are developed to establish the baseline and to analyse the demand and comfort of the buildings under different renovation scenarios in order to validate the sustainable construction strategies to be implemented. Moreover, new standards are also defined in order to reduce energy and water consumption and increase indoor air quality and comfort in buildings. In an attempt to generate evidence and facilitate the replication and implementation of sustainable construction standards, three Living Labs (LLs) are created to validate different strategies and technological solutions in different locations, according to the defined standards: a school in Santa Cruz, a hotel in Isabela, and a residential building in San Cristóbal. The findings highlight the effectiveness of specific energy-saving strategies and water conservation measures validated through Living Labs implemented in different locations across the islands. Furthermore, the knowledge generated is transferred through local training of the agents of the construction chain and administration.Peer reviewe
Comprehensive prospective environmental assessment of innovative photovoltaic technologies: Integration into electricity grids in Finland, Germany, and Spain
Full text linkPublisher Copyright: © 2025This study evaluates the environmental performance of advanced solar photovoltaic technologies, including floating, bifacial ground-mounted, and building-integrated photovoltaics systems, compared to conventional technologies in Finland, Germany and Spain from 2022 to 2050. A novel aspect of this research is the integration of multiple photovoltaics technologies, time horizons (2022, 2030, and 2050), and climatic zones, providing a more complete understanding of their lifecycle impacts. The study uses a prospective life cycle assessment approach, offering scenario-based projections to assess future environmental impacts under changing energy mixes and climatic conditions. The results highlight the critical role of local solar irradiation, as seen in the higher carbon footprint of floating photovoltaic systems in Murcia (30.2 gCO2/kWh, 2022) than in Lappeenranta (15.7 gCO2/kWh). Over time, environmental impacts decrease significantly; floating photovoltaics in Murcia reduces to 17.5 gCO2/kWh in 2050, and bifacial systems drop from to 14.9 gCO2/kWh. Overall, bifacial systems have the lowest environmental impact, followed by floating photovoltaics, while building-integrated systems show the highest impact. The findings highlight the critical importance of transitioning to renewable energy in electricity grids to reduce environmental impacts, while emphasizing the role of location-specific factors, technological advancements, and evolving energy systems in shaping the environmental performance of photovoltaics technologies.Peer reviewe
Leveraging Hyperledger Fabric for Criminal Evidence Integrity-Proofs
No full textPublisher Copyright: © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.Nowadays, digital evidence plays a significant role in criminal investigations due to the widespread use of technology in daily life. As in the case of physical evidence, digital evidence requires suitable and secure handling and storage processes to guarantee its integrity and be admissible in a court. This paper presents a blockchain-based integrity-proof system that leverages the security features of Hyperledger Fabric to enable secure and reliable evidence. This system also enhances the usability of the blockchain technology, allowing authorities with no technical knowledge to use it. The design and specific implementation are described in detail, resulting in a real prototype for a reliable, secure, and user-friendly criminal evidence integrity-proof system. This system has been successfully used in the analysis of car accidents, resulting in a very useful tool for securing car accident 3D reconstruction and energetic analysis.Peer reviewe
Novel Bio-Based Formulations for Alkyd Wood Coatings: Effects on Biodegradation and Technical Performance
Full text linkPublisher Copyright: © 2025 by the authors.Alkyd resins are still one of the most important classes of binders for paint systems. They are outstanding in terms of their versatility of formulations and applications, cost-effectiveness, and durability. Traditionally, they are synthesized using phthalic anhydride, polyalcohols with three or four functional groups (pentaerythritol, glycerol, and trimethylolpropane), and fatty acids or oils. In this study, new bio-alkyd resins were synthesized with the objective of increasing the bio-based content by substituting phthalic anhydride, thereby also enhancing the biodegradability of coatings. The newly synthesized alkyd resins, formulated with azelaic acid, were used to develop coatings incorporating additives while avoiding cobalt-based driers. Additional agents such as leveling, wetting, and anti-skinning agents, were also included. Paints were applied to wood substrates and dried at room temperature. The resulting films were characterized by pendulum hardness, transparency, and color by colorimetry, cross-cut test, contact angle, and gloss. Thermal properties were analyzed by Differential Scanning Calorimetry (DSC), and Total Organic Carbon (TOC) content and aerobic biodegradation were also evaluated. The resulting coating films exhibited good mechanical performance, with hardness values ranging from 132 to 148 Persoz oscillations and strong adhesion to wood substrates (smooth cross-cut edges, Class 0). Significant biodegradability (70% in less than 90 days) was demonstrated under composting conditions, which was considerably higher than that of a commercial reference alkyd coating (34.7%) under the same conditions. These findings suggest that the developed bio-alkyd coatings formulated with azelaic acid and DCO-FA without cobalt-based driers represent a promising alternative to conventional phthalic acid-based alkyds. These novel coatings move closer to fully bio-based formulations and offer enhanced biodegradability, making them a more sustainable option for coating applications.Peer reviewe
Satellite image classification with neural quantum kernels
Full text linkPublisher Copyright: © 2025 The Author(s).Achieving practical applications of quantum machine learning (QML) for real-world scenarios remains challenging despite significant theoretical progress. This paper proposes a novel approach for classifying satellite images, a task of particular relevance to the earth observation industry, using QML techniques. Specifically, we focus on classifying images that contain solar panels, addressing a complex real-world classification problem. Our approach begins with classical pre-processing to reduce the dimensionality of the satellite image dataset. We then apply neural quantum kernels-quantum kernels derived from trained quantum neural networks-for classification. We evaluate several strategies within this framework, demonstrating results that are competitive with the best classical methods. Key findings include the robustness of or results and their scalability, with successful performance achieved up to 8 qubits.Peer reviewe
An Authentication System Based on Self-sovereign Identity for Vehicle-to-Vehicle (V2V) Communications
No full textPublisher Copyright: © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.In the evolving landscape of connected vehicles, secure and reliable communication between them (V2V) is crucial. In this scenario, a cornerstone is the achievement of the security service of authentication, that is, guaranteeing that right users with the right permissions are those who get specific resources. The present work proposes an authentication system based on Self-Sovereign Identity (SSI) to protect Vehicle-to-Vehicle (V2V) communications. Its implementation is based on the use of the Hyperledger Aries Cloud Agent (ACA-Py) and Arduino platform. The ACA-Py is a key component of the Hyperledger Aries project and has been designed to facilitate the development of Self-Sovereign Identity (SSI) services by abstracting developers of the logic of SSI methods. In this work, we have implemented an ACA-py controller on an Arduino SP32 board and conducted a series of experiments to assess its performance, with the aim of evaluating if SSI implementations using low-resource devices as Arduino are feasible. Our findings reveal that, when a proper design and adaptation is done, an ACA-Py controller can be run on an Arduino without any issues. Consequently, an authentication mechanism based on SSI can be integrated as a piece of software in vehicles for helping to protect V2V communications.Peer reviewe
EMERALD: Evidence Management for Continuous Certification as a Service in the Cloud
No full textPublisher Copyright: Copyright © 2025 by SCITEPRESS - Science and Technology Publications, Lda.The conspicuous lack of cloud-specific security certifications, in addition to the existing market fragmentation, hinder transparency and accountability in the provision and usage of European cloud services. Both issues ultimately reflect on the level of customers’ trustworthiness and adoption of cloud services. The upcoming demand for continuous certification has not yet been definitively addressed and it remains unclear how the level’high’ of the European Cybersecurity Certification Scheme for Cloud Services (EUCS) shall be technologically achieved. The introduction of AI in cloud services is raising the complexity of certification even further. This paper presents the EMERALD Certification-as-a-Service (CaaS) concept for continuous certification of harmonized cybersecurity schemes, like the EUCS. EMERALD CaaS aims to provide agile and lean re-certification to consumers that adhere to a defined level of security and trust in a uniform way across heterogeneous environments consisting of combinations of different resources (Cloud, Edge, IoT). Initial findings suggest that EMERALD will significantly contribute to continuous certification, boosting providers and users of cloud services to maintain regulatory compliance towards the latest and upcoming security schemes.Peer reviewe