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Wear Resistance of Aluminum Matrix Composites’ Coatings Added on AA6082 Aluminum Alloy by Laser Cladding
No full textWe present a study of wear resistance of Aluminum Matrix Composites’ Coatings Added on AA6082 Aluminum Alloy by Laser Claddin
Monitoring of Power Over Fiber Signals Using Intercore Crosstalk in ARoF 5G NR Transmission
No full textPower over Fiber (PoF) needs safe and resilient operation of the infrastructure. In this article, we propose a new crosstalk-based remote monitoring technique of PoF signals in Spatial Division Multiplexing optical networks with no additional consumption at the remote radio head (RRH). We demonstrate this technique in a 250 m 7-core Multicore Fiber (MCF) transmitting three multiplexed 256 QAM 5G NR optical signals with a total throughput of 1.8 Gbps, a low-speed communications channel between a Central Office and a RRH, and a PoF signal delivering to feed the RRH's control board. The 5G NR optical signals are received at the RRH with EVM values within the limits stablished in the 3GPP 5G standard. The low-speed communications channel remotely manages the power supplied to a Radio Frequency Power Amplifier located at the RRH. The PoF signal is used to supply up to 131 mW to the control board of the RRH. The monitoring channel can accurately follow the optical power injected into the MCF or the optical power received at the RRH thanks to a real-time algorithm and an ad-hoc Matlab application, which also allows to control the PoF source and the low-speed communications channel
PYPSHORT: Minimum short-circuit current optimization model
No full textOptimization model to guarantee minimum levels of short-circuit current at specified nodes of a transmission system. The model includes the short-circuit current injected under fault conditions by inverter-based resources. To reach the specified short-circuit current, synchronous condensers are allocated across the network at a minimum cost. The model is written on Pyomo and can be solved using off-the-shelf MILP solvers such as CPLEX or Gurobi
Perceived anxiety in family caregivers of individuals with Autism Spectrum Disorder, Down Syndrome and Williams Syndrome during the lockdown of the first COVID-19 wave in Spain. Data set.
No full textThis is a subsection of the Spanish data collected for an international Project (https://doi.org/10.17605/OSF.IO/5NKQ9) focused on studying the impact and response to the COVID-19 lockdown across the world for families of individuals with special needs.
In this particular Spanish subproject we studied the emotional impact of the strict lockdown during COVID-19 on Spanish caregivers of individuals with Autism Spectrum Disorder, Williams Syndrome and Down syndrome. Data were collected through an online survey. All caregivers reported concerns directly related to the pandemic and lockdown situation. Anxiety was predicted by previous anxiety disorder and the child’s diagnosis. The confinement in Spain was especially demanding for families of individuals with ASD
Update on Opium Alkaloids in Food: Exploring Their Occurrence, Effect of Culinary Processing and Advances in Analytical Methodologies
No full textFollowing the implementation of the new European legislation on opium alkaloids (OAs) in food in 2023, scientific research has focused on developing analytical methodologies to determine the presence of these compounds in different foods. However, health authorities continue to suggest further studies to evaluate the occurrence of main OAs and the impact of culinary processing. Concerns remain regarding the potential health risks associated with consuming foods containing OAs. This review provides an updated overview of OAs on food, addressing their occurrence, toxicity, and the risks and benefits associated with poppy seed consumption. It compiles data from recent studies and official reports, including notifications from the Rapid Alert System for Food and Feed (RASFF). Additionally, the influence of culinary processing on OAs concentration is analyzed, highlighting the main findings and research gaps. The review also discusses advancements in analytical methodologies, with emphasis on improvements in green sample preparation to purify extracts and validation of methodologies to improve detection reliability. Elevated concentrations of OAs above legislated limits have been reported. However, various culinary processing methods allow for significant reduction of these levels. Proper control of the initial concentration, together with appropriate processing practices, can mitigate the risks associated with ingestion of contaminated foods. Despite methodological advances in detection, further refinement of analytical methods for different food matrices is needed. Future research should focus on the optimization of these methods for the determination of all OAs, besides morphine and codeine, as well as on the effects of processing and the possible formation of degradation compounds
Fast and green methodology based on miniaturised liquid–liquid extraction with a hydrophobic natural deep eutectic solvent of opium alkaloids from poppy seed beverages
No full textCurrently, the development of environmentally friendly analytical methodologies is a challenge for analytical chemistry. Therefore, the search for solvents to extract analytes of interest from complex matrices has progressed considerably in recent years. In the present work, 15 hydrophobic natural deep eutectic solvents (HNADES) consisting of a mixture of different donors and acceptors in different ratios have been prepared and compared to evaluate the most efficient extraction of opium alkaloids (OA) from fortified water samples. After selecting the most effective one consisting in a mixture of thymol and camphor in the ratio 1:1 ([Thy]:[Cam] 1:1), a rapid analytical methodology to determine OA in poppy seed beverages was optimised and validated for the first time. It was based on a miniaturised liquid–liquid extraction (m-LLE) with 0.5 mL of sample and 0.5 mL of HNADES by vortexing for 1 min, followed by 1 min centrifugation and subsequent analysis by high-performance liquid chromatography with diode array detector (HPLC-DAD). The validation was successful, showing extraction efficiencies between 91 and 107 % for all analytes, low limits of quantification (0.1 µg/mL for all analytes, except for morphine, 0.4 µg/mL) and precision values below 15 %. In addition, the greenness of the method was evaluated, obtaining a 0.79 on the AGREEprep metric scale. Therefore, it was demonstrated that the methodology developed to analyse OAs in poppy seed beverage was efficient, fast, simple and environmentally friendly
Decision support system in multimorbidity and polypharmacy: usability and cognitive load of primary care physicians
No full textObjetivo: Evaluar la eficiencia de la usabilidad de un sistema de apoyo a la toma de decisiones (SAD) para médicos de atención primaria (MAP) que gestionan pacientes con multimorbilidad y polifarmacia.
Materiales y métodos: Estudio descriptivo transversal de usabilidad. La población de estudio fueron PCP con práctica asistencial activa en multimorbilidad y sin experiencia previa en el uso de la herramienta DSS. La variable principal fue la eficiencia de la usabilidad, medida por el tiempo de finalización de la tarea y las métricas de carga cognitiva (cuestionario NASA-TLX, métricas de seguimiento ocular y número de clics realizados). Se evaluaron nueve tareas basadas en un caso clínico simulado
Impact of Remelting in the Microstructure and Corrosion Properties of the Ti6Al4V Fabricated by Selective Laser Melting
No full textWe present the study of the corrosion behavior of the Ti6Al4V alloy manufactured by LPBF with CO2 lasers using the remelting of layers strategie
Macroscopic structures based on La0.8Me0.2NiO3±δ (Me = Al, Ba and Ca) perovskites for renewable hydrogen production through thermochemical water splitting
No full textThe worrying energy and climate situations make it necessary to face a transition to a carbon-neutral economy. In this context, green hydrogen plays a crucial role in the future energy landscape. Besides other technologies, thermochemical water splitting represents a promising route for renewable hydrogen generation, using thermosolar energy as the primary energy source.
In this study, different types of perovskites La0.8Me0.2NiO3±δ (Me = Al, Ba and Ca) were synthesised via reactive grinding. Their redox performance was evaluated under different thermal reduction temperatures (1200-800 °C), obtaining materials with hydrogen production values ranging from 4.51 to 5.31 cm3STP/gmaterial·cycle when the reduction was performed at 800 °C, exceeding those already reported values for similar materials at higher temperatures. In order to obtain suitable configurations for their implementation in solar reactors, powdered perovskites were shaped into macrostructures such as pellets, reticulated porous ceramic (RPC) structures and thin films deposited over ceramic monoliths. Compared to powdered materials, the macrostructures exhibited higher hydrogen production attributed to enhanced gas-solid contact and more efficient heat transfer within the structures. The best performance was obtained by La0.8Ca0.2NiO3±δ supported as a thin layer over the ceramic monolithic structure, with productions up to 14.91–16.33 cm3STP/gmaterial·cycle using thermal reduction temperatures of 800 and 1000 °C, respectively.
These results confirm that shaping strategies enhance the already remarkable redox activity of perovskites and enable their integration into volumetric solar reactors. This represents a significant step forward in the development of scalable green hydrogen production systems based on renewable solar thermal energy
Computational Thinking Measurement of CS University Students
No full textThe measurement of computational thinking ability among computer science (CS) university students is of paramount importance. This study introduces UniCTCheck, a novel method designed to assess the main components of computational thinking in CS students. Utilising two key instruments, namely, the web application CTScore and the psychometric scale CTProg, this research aims to precisely evaluate seven core components of computational thinking and six programming concepts skills essential for CS students. The study, conducted at Rey Juan Carlos University and Atlantic
Technological University Galway, involved a diverse sample of students from different year levels and programme specialisations. Through a rigorous research design, including sampling strategies and data collection tools, this study seeks to address critical research questions related to the measurement of variations in students’ computational thinking and programming skills by gender, university level, and location. By shedding light on the significance of computational thinking and programming in
the educational realm, this research contributes to the existing literature and underscores the essential role of computational skills in the modern era