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Cold Climate Wind: Challenges, Technological Solutions and Policy
No full textCold-climate wind power represents a major subset of onshore global capacity, with approximately one third of existing installations located in regions prone to low temperatures and icing. The main technical challenge in cold-climate conditions is ice accretion on turbine blades, which degrades aerodynamic performance and causes production losses, while ice falling from turbines poses a significant safety risk. These issues have driven the development of specialized technological solutions, including ice detection and mitigation systems and detailed forecasting models. In parallel, specific policy approaches have also been developed to address increased icing risks. This review focuses on wind turbine blade icing and related issues for onshore wind. It presents state-of-the-art technical solutions for icing-related challenges, as well as approaches for icing modeling and forecasting of icing conditions. In addition, relevant policies from different countries are reviewed. Production losses due to icing are highly variable, influenced by ice thickness, shape, and post-icing wind conditions. Accurate estimation and forecasting of these losses require advanced tools, ranging from SCADA-based analyses to machine learning methods and mesoscale weather prediction models. Ice detection technologies are being developed based on both direct and indirect measurement principles. Efforts to validate and certify these systems for operational use, such as automatically stopping and starting turbines, are ongoing. Icing mitigation includes both active technologies, such as blade heating systems, and passive approaches, such as icephobic coatings. Uncertainty quantification has become central to project financing and planning, with standards emerging to guide risk assessment. Policy and regulatory responses vary internationally: some regions, like Québec, mandate cold-climate certifications and real-time operational data reporting, while others focus on risk assessments and safety zones. Regulatory approaches remain somewhat fragmented and guided by local priorities. Further harmonization is needed to address critical safety issues such as ice throw
Progress in deep cleaning and upgrading of biomass- and waste-derived syngas for production of renewable fuels, chemicals and power
No full textThe cleaning of syngas for the production of renewable fuels, chemicals and power is reviewed here. Recent progress in syngas cleaning pathways and key utilization routes, along with techno-economics are discussed, with the goal of investigating the requirements of crude syngas towards clean syngas and finally towards fuels and chemicals as a sustainable and eco-friendly technology. The impacts of feedstock composition, type and characteristic properties on syngas quality coupled with the role of different impurities are examined. Furthermore, adaptation of process parameters and its impact on the syngas quality is discussed. Cleaning of crude syngas is considered a critical issue to generate renewable fuels and chemicals, and therefore, diverse pathways (conventional such as hot and cold cleaning methods, catalytic cleaning and thermal cracking and, advanced techniques such as membranes, pressure swing adsorption, and cryogenic separation) are presented to allow effective cleaning which in turn can enable syngas deployment in various applications. Bio-methane has emerged as a beneficial alternative for conventional transportation fuel with all the advantages of natural gas including a dense distribution, trade and supply network. Gasification is a proven technology while gas cleaning is still one limiting factor since “classical” pathways are labor and cost intensive, especially when it comes to residues and waste materials as feedstock. Gasification of organic feedstock materials (clean biomass, residues and waste) followed by chemical synthesis is a key-technology to substitute chemicals and fuels from fossil sources. These syngas-derived fuels and chemicals have the potential to provide sustainable energy and curb climate change to a major extent and therefore, can be a step forward towards the United Nation's Sustainable Development Goals 7 and 13.</p
Advanced Assessment of Stroke in Retinal Fundus Imaging with Deep Multi-view Learning
No full textStroke is globally a major cause of mortality and morbidity, and hence, accurate risk assessment and diagnosis of stroke are valuable. Retinal fundus imaging reveals the known markers of elevated stroke risk in the eyes, which are retinal venular widening, arteriolar narrowing, and increased tortuosity. In contrast to other imaging techniques used for stroke assessment, the acquisition of fundus images is easy, non-invasive, fast, and inexpensive. This paper examines the feasibility of utilizing retinal fundus imaging to differentiate individuals with stroke or transient ischemic attack (TIA), aiming to assess its potential for screening or diagnostic applications. Therefore, in this study, we propose a multi-view stroke network (MVS-Net) to detect stroke and TIA using retinal fundus images. Contrary to existing studies, our study proposes for the first time a solution to discriminate stroke and TIA with deep multi-view learning by proposing an end-to-end deep network, consisting of multi-view inputs of fundus images captured from both right and left eyes. Accordingly, the proposed MVS-Net defines representative features from fundus images of both eyes and determines the relation within their macula-centered and optic nerve head-centered views. Experiments performed on a dataset collected from stroke and TIA patients, in addition to healthy controls, show that the proposed framework achieves an AUC score of 0.84 for stroke and TIA detection.</p
Processing and performance of HVAF-sprayed Fe-based bulk metallic glass coatings:A sustainable alternative
No full textBulk metallic glasses (BMGs) are increasingly recognized as promising materials for surface engineering due to their exceptional hardness, corrosion resistance, and wear resistance, which are critical attributes for components operating in harsh environments. Fe-based BMGs offer a sustainable alternative to conventional coatings that often rely on toxic or scarce raw materials, thus aligning with global environmental and regulatory objectives. This study focuses on a newly developed Fe-based BMG alloy with enhanced glass-forming ability and processability for thermal spray applications. While BMGs exhibit outstanding properties, their limited ductility poses significant processing challenges, including propensity to cracking during deposition. To overcome this, the feasibility of producing dense Fe-based BMG coatings using High Velocity Air Fuel (HVAF) spraying was examined, aiming for superior wear and corrosion resistance. Initial trials resulted in coatings with severe cracking, delamination, and poor adhesion. However, systematic manipulation of spray parameters led to coatings with markedly reduced cracking, improved adhesion, and enhanced microstructural integrity. Comprehensive characterization included microstructure, amorphicity, and hardness examination, complemented by wear and corrosion performance assessments. The promising results represent a critical step toward establishing Fe-based BMGs as viable and environmentally friendly coating solutions via HVAF thermal spraying.</p
Towards the development of a CRISPR-Cas9 based kill switch for Saccharomyces cerevisiae
No full textBACKGROUND: Advancements in synthetic genetic circuits have enabled programmable and condition-dependent control of microbial cell growth. CRISPR-Cas9-based kill switches, genetic systems that program cells to lose viability in response to specific conditions, have recently been demonstrated for bacterial cell factories but not yet in yeast.RESULTS: In this study, we present a foundational demonstration for a CRISPR-based ki ll s witch in S accharomyces cerevisiae, CRISPR KiSS. The CRISPR KiSS employs inducible CRISPR targeting essential genes to elicit growth inhibition. The activation of the KiSS system is achieved through conditional expression of a guide RNA (gRNA) upon anhydrotetracycline (ATc) induction, thereby activating CRISPR-mediated gene disruption. We demonstrate that targeting the essential genes ( ERG13, PGA3, TPI1 or CDC19) leads to severe growth inhibition upon ATc induction. Still, the current set up does not allow complete killing of the cells due to system inactivation, e.g. escape from CRISPR based cutting. We studied reasons for system inactivation and substantially improved the system by simultaneous expression of two different gRNAs. Sequencing escape mutants revealed mutations in both the gRNA sequences and target genes as potential sources of system inactivation. CONCLUSIONS: This work highlights the potential of harnessing a CRISPR-based kill switch in S. cerevisiae. Cells expressing the system were able to escape growth inhibition through mutations and further optimization of the KiSS system is still needed for it to be used in various cell factory applications. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12934-026-02959-2.</p
IoT Service Orchestration in Edge-Cloud Continuum with 6G:A Review
No full textThe development of 6th-generation (6G) mobile networks brings advancements in wireless communications, including lower latency, higher data rates, and improved spectral efficiency, as well as enhanced facilitation for the use of Artificial Intelligence (AI) technologies, integrated communications, sensing, and renewable energy sources. To harness this potential, a scalable framework integrating edge and cloud computing is needed to provide a robust computing continuum for various IoT applications and services. This paper analyses the strengths and weaknesses of existing and emerging distributed computing frameworks—ranging from traditional centralized IoT architectures, through fog, edge, and local-edge architectures, to the full three-tier edge–cloud continuum—in terms of IoT service orchestration and diverse application requirements. We emphasize the latest evolutionary step, three-tier edge-cloud continuum, which aims to resolve the most significant limitations of the previous frameworks, recognized in the literature. It enables efficient IoT service orchestration by utilizing distributed resources and computation closer to end users, while taking full advantage of the centralized resources at data centers. We evaluate the maturity of these frameworks, considering factors such as scalability, resource efficiency, adaptability to changes, resource availability, security and privacy, as well as robustness and resilience. Overall, this study aims to serve as a roadmap for researchers, network architects, and industry stakeholders to make informed decisions on implementing the computing continuum in 6G networks.</p
Europe-wide maps of biomass density based on satellite remote sensing data for 2017, 2020, 2021 and 2023
No full textSpatially explicit information on forest structure and biomass is needed to meet the monitoring and reporting requirements of several European policies. Satellite images enable mapping and monitoring of the Europe’s forest resources through operational observations from the Sentinel-1 Synthetic Aperture Radar (SAR) and the Advanced Land Observing Satellite 2 (ALOS-2) Phased Array l -band SAR 2 (PALSAR-2) instruments. Data acquired in 2017, 2020, 2021 and 2023 were used to generate annual maps of forest biomass variables, namely Growing Stock Volume (GSV), Aboveground Biomass (AGB) and Belowground Biomass (BGB), with a pixel size of 20 m × 20 m. All products are in the geometry of the Sentinel-2 tiling system. A spatially averaged map with a pixel size of 100 m × 100 m (1 hectare) in geographic projection is also supplied, for users who do not require the highest spatial resolution. The maps were generated with a fully documented processing chain that includes (i) pre-processing of the SAR data to create stacks of co-registered terrain geocoded images of the backscattered intensity and (ii) inversion of a physically-based model to estimate GSV. AGB and BGB were subsequently estimated using allometric relationships. Per-pixel standard deviations were computed for each biomass variable by propagating uncertainties from both the SAR observations and the model parameters. The maps clearly reproduce the expected spatial patterns of forest biomass across Europe and provide sufficient spatial detail to identify biomass dynamics related to, e.g., logging and regrowth. Validation against measurements collected by National Forest Inventories (NFIs) indicates poor agreement with map values at the pixel scale, with errors larger than 50% of the reference biomass. The correspondence substantially improved for spatial aggregates, such as administrative units, for which the bias was mostly negligible and the mean square error was below 30% of the reference value. The number of ALOS-2 PALSAR-2 images affected the inter-annual consistency of the maps, which was lower in regions with only one or two observations per year.</p
Measuring damage anisotropy in concrete from ultrasound velocity data
No full textThe uniaxial compression of an initially isotropic concrete specimen induces a damage pattern that is anisotropic: in the direction of loading, the concrete undergoes compaction, while in the directions orthogonal to the loading direction, concrete cracking can be observed. In order to quantify such damage patterns, one possibility is to observe the changes in the stiffness tensor of a compressed specimen with respect to the stiffness tensor of the corresponding virgin state specimen. The eigensolutions of the Kelvin–Christoffel matrix for anisotropic media provide the relation between ultrasound wave velocities in given wavefront and polarization directions and the stiffness matrix components. In this study, it is shown how using the through transmission method for the determination of first-time arrival, one can evaluate the sound wave velocities in different directions and compute the stiffness tensor components for a damaged concrete specimen. Plots of stiffness tensor components as a function of non-recoverable strain give a qualitative measure of the anisotropic strain degradation process
MITE: the Minimum Information about a Tailoring Enzyme database for capturing specialized metabolite biosynthesis
No full textSecondary or specialized metabolites show extraordinary structural diversity and potent biological activities relevant for clinical and industrial applications. The biosynthesis of these metabolites usually starts with the assembly of a core ‘scaffold’, which is subsequently modified by tailoring enzymes to define the molecule’s final structure and, in turn, its biological activity profile. Knowledge about reaction and substrate specificity of tailoring enzymes is essential for understanding and computationally predicting metabolite biosynthesis, but this information is usually scattered in the literature. Here, we present MITE, the Minimum Information about a Tailoring Enzyme database. MITE employs a comprehensive set of parameters to annotate tailoring enzymes, defining substrate and reaction specificity by the expressive reaction SMARTS (Simplified Molecular Input Line Entry System Arbitrary Target Specification) chemical pattern language. Both human and machine readable, MITE can be used as a knowledge base, for in silico biosynthesis, or to train machine-learning applications, and tightly integrates with existing resources. Designed as a community-driven and open resource, MITE employs a rolling release model of data curation and expert review. MITE is freely accessible at https://mite.bioinformatics.nl/
Some Problems in the Ethical Impact Assessment of Emerging Technologies and Socio-Technical Visions:Case CityVerse
No full textThis paper examines methodological challenges in the participatory ethical assessment of emerging technologies in urban contexts, using the CityVerse vision in Tampere, Finland as a case study. While metaverse technologies promise to transform smart cities by blending physical and virtual spaces, their ethical implications remain unclear. Through focus groups with city officials, we explored how participatory methods can effectively evaluate ethical dimensions of emerging technologies when they remain largely conceptual. Our findings reveal that while stakeholders can generate substantive ethical discourse, they struggle with the abstract nature of metaverse experiences, producing more questions than definitive answers. We argue that sociotechnical visions serve better as platforms for ethical discourse than as concrete implementation plans, functioning primarily to surface tacit values and assumptions. The study contributes to ethical technology assessment methodologies by suggesting that for emerging technologies, developing structured ontologies of questions may prove more valuable than premature answers. We conclude that CityVerse design should be approached as an ongoing discourse—not merely about technologies, but fundamentally about designing for improved quality of human life—where participatory ethical vision assessment functions as a form of collaborative conceptual engineering.</p