Search Results (281)

With the advancement of modern fan architectures, dedicated experimental benchmarks are becoming fundamental to improving the knowledge of flow physics, validating novel CFD methods, and fine-tuning existing methods. In this context the open test case ECL5/CATANA, representative of a modern Ultra High Bypass Ratio (UHBR) architecture, has been designed and experimentally investigated at École Centrale de Lyon (ECL) in a novel test facility with multi-physical instrumentation, providing a large database of high-quality aerodynamic and aeromechanic measurements. In this paper, a thorough numerical study of the fan stage aerodynamics was performed using the CFD TRAF code developed at the University of Florence. Fan stage performance was studied at design speed over the entire operating range. The results were discussed and compared with datasets provided by ECL. Detailed sensitivity on numerical schemes and state-of-the-art turbulence/transition models allowed for the selection of the best numerical setup to perform UHBR fan simulations. Moreover, to have a deeper understanding of the fan stall margin, unsteady simulations were also carried out. The results showed the appearance of blade tip instability, precursor of a rotating stall condition, which may generate non-synchronous blade vibrations. Full article

This study identifies the optimal location for an offshore energy island to supply sustainable power to desalination plants along the Red Sea coast. As demand for clean energy in water production grows, integrating renewables into desalination systems becomes increasingly essential. A decision-making framework was developed to assess site feasibility based on renewable energy potential (solar, wind, and wave), marine traffic, site suitability, planned developments, and proximity to desalination facilities. Data was sourced from platforms such as Windguru and RETScreen, and spatial analysis was conducted using Inverse Distance Weighting (IDW) and Multi-Criteria Decision Analysis (MCDA). Results indicate that the central Red Sea region offers the most favorable conditions, combining high renewable resource availability with existing infrastructure. The estimated regional desalination energy demand of 2.1 million kW can be met using available renewable sources. Integrating these sources is expected to reduce local CO₂ emissions by up to 43.17% and global desalination-related emissions by 9.5%. Spatial constraints for offshore installations were also identified, with land-based solar energy proposed as a complementary solution. The study underscores the need for further research into wave energy potential in the Red Sea, due to limited real-time data and the absence of a dedicated wave energy atlas. Full article

Steel lazy wave risers (SLWRs) are critical in offshore hydrocarbon transport for linking subsea wells to floating production facilities in deep-water environments. The incorporation of buoyancy modules reduces curvature-induced stress concentrations in the touchdown zone (TDZ); however, extended operational exposure under cyclic environmental and operational loads results in repeated seabed contact. This repeated interaction modifies the seabed soil over time, gradually forming a trench and altering the riser configuration, which significantly impacts stress patterns and contributes to fatigue degradation. Accurately reconstructing the riser’s evolving profile in the TDZ is essential for reliable fatigue life estimation and structural integrity evaluation. This study proposes a simulation-based framework for the autonomous tracking of SLWRs using a fin-actuated autonomous underwater vehicle (AUV) equipped with a monocular camera and multibeam echosounder. By fusing visual and acoustic data, the system continuously estimates the AUV’s relative position concerning the riser. A dedicated image processing pipeline, comprising bilateral filtering, edge detection, Hough transform, and K-means clustering, facilitates the extraction of the riser’s centerline and measures its displacement from nearby objects and seabed variations. The framework was developed and validated in the underwater unmanned vehicle (UUV) Simulator, a high-fidelity underwater robotics and pipeline inspection environment. Simulated scenarios included the riser’s dynamic lateral and vertical oscillations, in which the system demonstrated robust performance in capturing complex three-dimensional trajectories. The resulting riser profiles can be integrated into numerical models incorporating riser–soil interaction and non-linear hysteretic behavior, ultimately enhancing fatigue prediction accuracy and informing long-term infrastructure maintenance strategies. Full article

This paper investigates integrating a sensory data model for managing an existing 50-year-old building. A primary challenge in retrofitting older structures is the optimal deployment of high-quality sensors, systematic data acquisition, and subsequent data management. To address this, the study implemented a network of over 50 sensors connected via 270 m of wired infrastructure, deliberately avoiding wireless transmission to ensure data reliability. This configuration generates 5568 data points daily, which are archived on a dedicated server. The data is planned for integration into the Campus Geographical Information System (GIS), enabling private and public access. A methodology was employed, involving the strategic placement of sensors based on building use patterns, continuous data monitoring, and iterative sensor performance evaluation. The findings from the study indicate that integrating sensory data through this structured approach significantly enhances building management capabilities. Specifically, the results demonstrate improved energy efficiency and environmental performance, which is particularly relevant for public and educational facilities. The research highlights that a data-driven, monitoring-based management system can optimize operational functions and inform future retrofitting strategies for aging buildings. Full article

Increasing the use of healthcare facilities has resulted in the growing production of biomedical waste, which poses health risks to users, health professionals, and the environment. The aim of this research is to study the correlation between governance in Togo’s public health facilities and the quality of biomedical waste management within these facilities. Methods: This was a cross-sectional, descriptive, and analytical study conducted from September to December 2024. It involved 264 public health facilities of all types in all health regions of Togo. Health facilities were selected using the simple random selection technique. Healthcare providers were selected using the reasoned choice technique. The statistical tests used were the chi-square test and logistic regression, which enabled proportions to be compared and confounding factors to be eliminated, respectively. Results: Multivariate analysis revealed a statistically significant association between the organization and training component of governance and the quality of biomedical waste management (BMWM) in health facilities (OR = 3.79; 95% CI [1.79–8.03]; p < 0.001). This relationship suggests that health facilities with functional infection prevention and control (ICP) or BMWM committees, trained staff at all levels (nursing, technical, and administrative), and dedicated waste management personnel are more likely to implement compliant waste management practices. Analyses of the data also revealed that, among the criteria for assessing the quality of biomedical waste management (BMWM), the most significant were sorting (OR = 1.482; 95% CI [1.286; 1.708]), quantification (OR = 2.026; 95% CI [1.491; 2.753]), transportation (OR = 1.403; 95% CI [1.187; 1.66]), and disposal infrastructure (OR = 1.604; 95% CI [1.298; 1.982]). The application of this grid shows that 17.8% of the health facilities surveyed had a score equal to or above 80% on all the criteria used to assess the quality of biomedical waste management, and they were therefore managing waste in an “acceptable” manner. The study highlights key findings in biomedical waste management practices, providing actionable insights for improving public health safety. Full article

The Volumetric Neutron Source (VNS) is a pivotal facility proposed for advancing fusion nuclear technology, particularly for the qualification of breeding blanket systems, a key component of DEMO and future fusion reactors. This study focuses on the design and optimisation of the VNS Thermal Shield, adopting a multidisciplinary approach to address its thermal and structural behaviours. The Thermal Shield plays a crucial role in protecting superconducting magnets and other cryogenic components by limiting heat transfer from higher-temperature regions of the tokamak to the cryostat, which operates at temperatures between 4 K and 20 K. To ensure both thermal insulation and structural integrity, multiple design iterations were conducted. These iterations aimed to reduce electromagnetic (EM) forces induced during magnet charge and discharge cycles by introducing strategic cuts and reinforcements in the shield design. The optimisation process included the evaluation of various aluminium alloys and composite materials to achieve a balance between rigidity and weight while maintaining structural integrity under EM and mechanical loads. Additionally, an integrated thermal study was performed to ensure effective temperature management, maintaining the shield at an operational temperature of around 80 K. Cooling channels were incorporated to homogenise temperature distribution, improving thermal stability and reducing thermal gradients. This comprehensive approach demonstrates the viability of advanced material solutions and design strategies for thermal and structural optimisation. The findings reinforce the importance of the VNS as a dedicated platform for testing and validating critical fusion technologies under operationally relevant conditions. Full article

The world is characterised by the growing volumes and flow of goods, which, amid benefits to economic development, result in negative externalities affecting the sustainability of cities. Although numerous studies have analysed the locational patterns of logistics facilities in cities, further research is required to examine their real estate patterns and trends. The aim of the paper is, therefore, to analyse the value of land accommodating logistics facilities in the City of Cape Town municipality, South Africa. Given the lack of dedicated geo-spatial data, logistics firms were searched on Google Maps, utilising a combination of aerial photography and street view imagery. Three main attributes of land parcels hosting logistics facilities were thereafter captured from the municipal cadastral information: property extent, street address, and property number. The latter two were used to extract the 2018 and 2022 property market values from the valuation rolls on the municipal website, followed by statistical, spatial, and geographically weighted regression (GWR) analyses. Zones near the central business district and seaport, as well as areas with prime road-based accessibility, had high market values, while those near the railway stations did not stand out. However, GWR yielded weak relationships between market values and the locational variables analysed, arguably showing a disconnect between spatial planning and logistics planning. Towards augmenting sustainable logistics, it is recommended that relevant stakeholders strategically integrate logistics into spatial planning, and particularly revitalise freight rail to attract investment to logistics hubs with direct railway access. Full article

A novel and general approach to the practical ROMP polymerization of cinchona alkaloid derivatives providing novel hybrid materials having quinine attached on a poly(norbornene-5,6-dicarboxyimide) matrix is presented. The concept involves an easy modification of quinine (in general, any cinchona alkaloid) toward clickable 9-azide that reacts with N-propargyl-cis-5-norbornene-exo-2,3-dicarboxylic imide in Cu(I)-catalyzed Huisgen cycloaddition (click chemistry). The resulting monomers undergo a controllable ROMP reaction that leads to novel polymers of a desired length and solubility. This sequence allows for the facile preparation of a regularly decorated polymeric material having one quinine moiety per single mer of the polymer chain inaccessible using typical immobilization methods. A poly(norbornene-5,6-dicarboxyimide) type of polymeric matrix was selected due to the high reactivity of the exo-norbornene motif in Ru(II)-catalyzed ROMP and its chemical and thermal stability as well as convenient, scalable access from inexpensive cis-5-norbornene-exo-2,3-dicarboxylic anhydride (‘one-pot’ Diels–Alder reaction of dicyclopentadiene and maleic anhydride). An appropriate combination of a Grubbs catalyst, Ru(II) (G1, G2), and ROMP conditions allowed for the efficient synthesis of well-defined soluble polymers with mass parameters in the range Mn = 2.24 × 10⁴ – 2.26 × 10⁴ g/mol and Mw = 2.90 × 10⁴–3.05 × 10⁴ g/mol with good polydispersity, Đ_M = 1.32–1.35, and excellent thermal stability (up to 309°C T_d10). Spectroscopic studies (NMR and electronic circular dichroism (ECD)) of these products revealed a linear structure with the slight advantage of a trans-configuration of an olefinic double bond. The resulting short-chain polymer discriminates mandelic acid enantiomers with a preference for the (R)-stereoisomer in spectrofluorimetric assays. This concept seems to be rather general with respect to other molecules dedicated to incorporation into the poly(norbornene-5,6-dicarboxyimide) chain. Full article

The introduction of COVID-19 vaccinations has significantly altered the course of the pandemic by markedly reducing the number of severe infection cases, hospitalizations, and deaths due to COVID-19. Elderly individuals constitute a particularly vulnerable group at risk of severe disease progression, which is often related to decreased immune system effectiveness and comorbidities. Severe infection outcomes in vaccinated individuals, though substantially rarer than in the unimmunized population, can still lead to death due to underlying health conditions. This analysis aims to describe the population of elderly individuals who, despite being vaccinated, died from interstitial pneumonia complicating SARS-CoV-2 infection. Data on the infection course and co-existing diseases were obtained from the database of the Józef Struś Multispecialty City Hospital in Poznań, which was converted into a dedicated facility during the pandemic. The inclusion criteria for the analysis were being over 60 years of age on the day of hospital admission, confirmed pneumonia in radiological examination, COVID-19 infection confirmed by PCR test, and an adverse disease course resulting in death. Patients admitted to the hospital from 1 June 2021 to 31 December 2021 were analyzed. Out of all hospitalizations, only 18 individuals met the inclusion criteria. Given the small number of patients, the authors employed descriptive methods to illustrate the clinical states of the individual patients, presenting SARS-CoV-2 infection in the context of co-existing diseases that significantly affect prognosis. The qualitative analysis employed highlights the complex and multidimensional courses of severely ill COVID-19 patients more emphatically. Full article

We present early follow-up observations of Einstein Probe (EP) X-ray transients, following its first year of operation. EP is a dedicated wide-field X-ray observatory that is transforming our understanding of the dynamic X-ray universe. During its first year, EP successfully detected a diverse range of high-energy transients—including gamma-ray bursts (GRBs), tidal disruption events (TDEs), and fast X-ray transients (FXTs), besides many stellar flares, disseminating 128 alerts in the aggregate. Ground-based optical follow-up observations, particularly those performed by our BOOTES telescope network, have played a crucial role in multi-wavelength campaigns carried out so far. Out of the 128 events, the BOOTES Network has been able to follow up 58 events, detecting 6 optical counterparts at early times. These complementary optical measurements have enabled rapid identification of counterparts, precise redshift determinations (such as EP250215a at $z=4.61$), and detailed characterization of the transient phenomena. The synergy between EP’s cutting-edge X-ray monitoring and the essential optical follow-up provided by facilities, such as the above-mentioned BOOTES Global Network or other Spanish ground-based facilities we have access to, underscores the importance and necessity of coordinated observations in the era of time-domain and multi-messenger astrophysics. Full article

Objective: Current good manufacturing practice (cGMP) guidance for positron emission tomography (PET) drugs has been established in Europe and the United States. In Japan, the Pharmaceuticals and Medical Devices Agency (PMDA) approved the use of radiosynthesizers as medical devices for the in-house manufacturing of PET drugs in hospitals and clinics, regardless of the cGMP environment. Without adequate facilities, equipment, and personnel required by cGMP regulations, the quality assurance (QA) and clinical effectiveness of PET drugs largely depend on the radiosynthesizers themselves. To bridge the gap between radiochemistry standardization and site qualification, the Japanese Society of Nuclear Medicine (JSNM) has issued guidance for the in-house manufacturing of small-scale PET drugs under academic GMP (a-GMP) environments. The goals of cGMP and a-GMP are different: cGMP focuses on process optimization, certification, and commercialization, while a-GMP facilitates the small-scale, in-house production of PET drugs for clinical trials and patient-specific standard of care. Among PET isotopes, N-13 has a short half-life (10 min) and must be synthesized on site. [¹³N]Ammonia ([¹³N]NH₃) is used for myocardial perfusion imaging under the Japan Health Insurance System (JHIS) and was thus selected as a working example for the manufacturing of PET drugs in an a-GMP environment. Methods: A [¹³N]NH₃-radiosynthesizer was installed in a hot cell within an a-GMP-compliant radiopharmacy unit. To comply with a-GMP regulations, the air flow was adjusted through HEPA filters. All cabinets and cells were disinfected to ensure sterility once a month. Standard operating procedures (SOPs) were applied, including analytical methods. Batch records, QA data, and radiation exposure to staff in the synthesis of [¹³N]NH₃ were measured and documented. Results: 2.52 GBq of [¹³N]NH₃ end-of-synthesis (EOS) was obtained in an average of 13.5 min in 15 production runs. The radiochemical purity was more than 99%. Exposure doses were 11 µSv for one production run and 22 µSv for two production runs. The pre-irradiation background dose rate was 0.12 µSv/h. After irradiation, the exposed dosage in the front of the hot cell was 0.15 µSv/h. The leakage dosage measured at the bench was 0.16 µSv/h. The exposure and leakage dosages in the manufacturing of [¹³N]NH₃ were similar to the background level as measured by radiation monitoring systems in an a-GMP environments. All QAs, environmental data, bacteria assays, and particulates met a-GMP compliance standards. Conclusions: In-house a-GMP environments require dedicated radiosynthesizers, documentation for batch records, validation schedules, radiation protection monitoring, air and particulate systems, and accountable personnel. In this study, the in-house manufacturing of [¹³N]NH₃ under a-GMP conditions was successfully demonstrated. These findings support the international harmonization of small-scale PET drug manufacturing in hospitals and clinics for future multi-center clinical trials and the development of a standard of care. Full article

Technological innovation toward electrification and digitalization is revolutionizing aviation, paving the way for new aeronautical paradigms and novel modes to transport goods and people in urban and regional environments. Advanced Air Mobility (AAM) leverages vertical and digital mobility, driven by safe, quiet, sustainable, and cost-effective electric vertical takeoff and landing (VTOL) aircraft. A key enabler of this transformation is the development of vertiports—dedicated infrastructure designed for VTOL operations. Vertiports are pivotal in integrating AAM into multimodal transport networks, ensuring seamless connectivity with existing urban and regional transportation systems. Their design, placement, and operational framework are central to the success of AAM, influencing urban accessibility, safety, and public acceptance. These facilities should accommodate passenger and cargo operations, incorporating charging stations, takeoff and landing areas, and optimized traffic management systems. Public and private sectors are investing in vertiports, shaping the regulatory and technological landscape for widespread adoption. As cities prepare for the future of aerial mobility, vertiports will be the cornerstone of sustainable, efficient, and scalable air transportation. Full article

Background: Current research on healthcare-associated infection (HAI) surveillance in traditional Korean medicine (TKM) institutions is limited. Methods: We utilized the Delphi method to evaluate the validity and feasibility of implementing an HAI surveillance system in TKM hospitals. This involved conducting a systematic literature review and focus group interviews with three infection control experts and five TKM doctors experienced in infection control within TKM hospitals. Based on these findings, we developed a Delphi questionnaire. The survey included a total of fifteen participants: ten TKM doctors and TKM-related policy researchers with infection control expertise, two infection control nurses, and three infectious disease doctors. Results: The survey results indicated strong consensus on the necessity of introducing an HAI surveillance system tailored to TKM hospitals, as well as their integration into the Korean National Healthcare-associated Infections Surveillance (KONIS) system. Since infectious diseases do not differentiate between acute care hospitals and TKM hospitals, it is reasonable for TKM hospitals to participate in infection surveillance systems. However, the feasibility of implementing HAI surveillance in TKM hospitals remains low due to a lack of awareness regarding infection surveillance, insufficient surveillance personnel, inadequate diagnostic and surveillance infrastructure, and limited policy support for infection control. Therefore, this study proposes a phased approach in which hand hygiene surveillance and safe injection practice monitoring, which received relatively higher consensus on feasibility, should be prioritized to establish the necessary surveillance infrastructure. Subsequently, a stepwise implementation of HAI surveillance can be introduced. Conclusions: Although TKM hospitals generally have a lower risk of HAIs compared to acute care facilities, they lack robust infection control systems and support. To address this gap, TKM hospitals should join the KONIS system. Appointing and training dedicated infection control personnel will enable their participation and enhance overall infection management. Full article

With the increased electrification of aircraft, the thermal management of associated heat loads becomes more and more of a challenge. While a classical airline aircraft typically has a system thermal emission in the same range as the heat generated by passengers, more innovative hybrid electric aircraft designs and hydrogen-powered aircraft can require up to 1 MW of cooling, which is two orders of magnitude larger than the heat load of the transported passengers. For the development of such systems, dedicated laboratory test environments are necessary to pre-assess technologies and flight conditions in research and maturation projects. The Flight Test Facility is one such facility, and this paper will outline some of the thermal tests performed in the past and planned enhancements of the testing capabilities. Full article

In recent years, the Italian peninsula has frequently been affected by fires in waste storage facilities, both accidental and malicious. Waste storage activities must comply with a series of regulations that require the employer to carefully assess the risks associated with the operation of the plant. All prevention and protection measures must be taken to reduce the risk of fires in order to safeguard both people and the environment. In addition, with new regulations coming into force in November 2022, efforts are being made to regulate waste treatment and storage facilities in terms of fire safety. This work presents simulations of the dispersion into the environment of toxic effluents produced during a polyethylene fire at a storage site, with the aid of dedicated software. Simulations were carried out using ALOFT, varying the parameters of the simulations (e.g., the burnt area, environmental characteristics, and toxic effluent investigated). In total, 24 simulations were carried out to investigate the emissions of particulate matter and volatile organic compounds in the case of polyethylene fires. The simulations showed that atmospheric stability class and wind speed had a significant impact on the dispersion. The proposed methodology can be applied both in the risk assessment and emergency phases and, eventually, as a valuable tool in post-accident analysis. Full article