Search Results (165)

Given an autonomous second-order ordinary differential equation (ODE), we define a Riemannian metric on an open subset of the first-order jet bundle. A relationship is established between the solutions of the ODE and the geodesic curves with respect to the defined metric. We introduce the notion of energy foliation for autonomous ODEs and highlight its connection to the classical energy concept. Additionally, we explore the geometry of the leaves of the foliation. Finally, the results are applied to the analysis of Lagrangian mechanical systems. In particular, we provide an autonomous Lagrangian for a damped harmonic oscillator. Full article

Artificial neural networks (ANNs) have become essential components in various safety-critical applications, including autonomous vehicles, medical devices, and avionics, where system failures can lead to severe risks. Edge AI devices, which process data locally without relying on the cloud, are increasingly used to meet the performance and real-time demands of these applications. However, their reliability in radiation-prone environments is a significant concern. In this context, this paper evaluates the MAX78000, an ultra-low-power Edge AI microcontroller with a hardware-based convolutional neural network (CNN) accelerator, focusing on its behavior in radiation environments. To assess the reliability of the MAX78000, we performed a test campaign at the ChipIR neutron irradiation facility using two different ANNs. We implemented techniques to improve system observability during ANN inference and analyzed the radiation-induced errors observed. The results present a comparative analysis between the two ANN architectures, which shows that the complexity of the ANN directly impacts its reliability. Full article

Background: The healthcare sector is currently undergoing a significant transformation, driven by an increased utilization of data. In this evolving landscape, surveys are of pivotal importance to the comprehension of patient needs and preferences. Moreover, the digital affinity of patients and physicians within the healthcare system is reforming the manner in which healthcare services are accessed and delivered. The utilization and donation of data are influencing the future of medical research and treatment, while artificial intelligence (AI) is empowering patients and physicians with knowledge and improving healthcare delivery. Methods: In order to evaluate the opinions of patients and physicians regarding the management of personal health data and the functionality of upcoming data management devices in the context of healthcare digitization, we conducted an exploratory study and designed a survey. The survey focused on a number of key areas, including demographics, experience with digitization, data handling, the identification of needs for upcoming digitization, and AI in healthcare. Results: A total of 40 patients and 15 physicians participated in the survey. The results indicate that data security, timesaving/administrative support, and digital communication are aspects that patients associate with patient-friendly digitization. Based on the responses provided by physicians, it might be concluded that future digital platforms should prioritize usability, time efficacy, data security, and interoperability. Conclusions: In terms of expectations for future digital platforms, there is a notable overlap between the needs expressed by patients and those identified by physicians, particularly in relation to usability, time management, data security, and digital communication. This suggests that the requirements of different stakeholders can be combined in a future system, although individual issues may still require attention. Full article

Transfer factors (TFs) are widely used tools for assessing the uptake of radionuclides by plants. The literature contains numerous studies on TFs in tropical and temperate climates; however, the existing data on TFs in arid and semi-arid climates are very scarce. Furthermore, the current trend in nuclear energy expansion in countries with this type of climate necessitates knowledge of the mechanisms of radionuclide incorporation by plants as well as the TF values. For this reason, this work investigates the TFs of ²³⁸U and ²²⁶Ra in plants in a study area during the summer period under conditions equivalent to a semi-arid climate. The selected plants were Scolymus hispanicus L., Eryngium campestre L., Chenopodium vulvaria L., and Chenopodium album L., which were collected in the vicinity of a waste dump from an abandoned copper mine. The selected study area has radionuclide levels above the global average, in addition to heavy metals, as it is a waste dump from an abandoned copper mine. The range of transfer factors for ²³⁸U varied between 1.5 × 10⁻⁴ kg⁻¹ kg⁻¹ and 7.8 × 10⁻³ kg⁻¹ kg⁻¹, while for ²²⁶Ra, the range was between 1.8 × 10⁻⁴ kg⁻¹ kg⁻¹ and 4.0 × 10⁻² kg⁻¹ kg⁻¹. The correlations found with PCA were (i) ²³⁸U with Fe and Al, and (ii) ²²⁶Ra with S, Ti, Ca, and Sr. A transfer model of ²³⁸U and ²²⁶Ra was created using multiple linear regression analysis. The model showed how ²³⁸U was related to the presence of Al, while ²²⁶Ra was related to Al, Fe, and Ti. The results obtained have allowed us to propose a model for the incorporation of ²³⁸U and ²²⁶Ra, taking into account the chemical composition of the soil. The results obtained indicate that both Scolymus hispanicus L. and Eryngium campestre L. could be utilized in phytoremediation for soils contaminated by natural radionuclides in semi-arid climates. The TFs, as well as the proposed model, allow us to expand the knowledge of the absorption of natural radionuclides by plants in regions with arid and semi-arid climates, which is necessary for the radiological risk assessment of future nuclear fuel cycle facilities. Full article

This study investigates the inhibitory and hormetic effects of Myriophyllum spicatum extract on Microcystis aeruginosa in a controlled, continuous culture environment. To address the global challenge posed by harmful algal blooms, we used a range of extract concentrations to delineate the growth response patterns. At very low concentrations (6.25 and 12.5 mg/L), the addition of M. spicatum extract shows no discernible reduction in M. aeruginosa cell density or growth rate; instead, a slight increase is observed during exposure, suggesting a hormetic effect. However, at higher concentrations (75 and 100 mg/L), there is a drastic reduction of more than 50% in cell density and growth rate at 75 mg/L, with complete inhibition at 100 mg/L, leading to pronounced oxidative stress, damage to antioxidant defense systems, and increased cell mortality. Increased levels of malondialdehyde, catalase, and superoxide dismutase activities indicate the involvement of these enzymes in combating oxidative stress. Furthermore, intracellular and extracellular microcystins were significantly decreased at higher extract concentrations (50, 75, and 100 mg/L) in a dose-dependent manner. Our results indicate a dose-dependent response and provide insight into the potential application of natural water treatment solutions. Implications for ecological management and future research directions are discussed. Full article

The objective of this study was to assess the impact of incorporating olive cake into the diet of indigenous Bísaro pigs on the quality of processed meat products. To this end, loins and “cachaços” were processed using a standardized manufacturing flowchart to produce dry-cured products. The two products were manufactured using the same formulation, ingredients, and curing process. Concerning the physicochemical composition, there were significant differences between the two products for the parameters of a_w (p < 0.001), moisture (p < 0.001), total fat (p < 0.001), protein (p < 0.001), and haem pigments (p < 0.001). The diet significantly impacted the NaCl content (p < 0.05). However, neither the product nor the diet affected the fractions of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), or polyunsaturated fatty acids (PUFA) (p > 0.05). However, a significant difference was observed for n-3 (p < 0.05). Adding olive cake increased these fatty acids, and the diet containing 25% centrifuged olive cake showed the highest levels for both products. Compared with the control, the diets containing olive cake had a higher content of n-3 fatty acids, resulting in a lower PUFA n-6/n-3 ratio (p < 0.01). Full article

Hydrokinetic energy constitutes a source of renewable energy. However, many regions have flow velocities that are too low for effective energy extraction, and conventional turbines are not suitable for these sites. In order to address this challenge, the present work proposes a novel vertical axis hydrokinetic turbine designed for environments where conventional turbines are not feasible due to a low water velocity. The turbine’s design is inspired by biological principles, enhancing the traditional Savonius turbine by incorporating a Fibonacci spiral-inspired blade configuration. The turbine’s performance was subjected to a rigorous analysis through Computational Fluid Dynamics (CFD). The results demonstrate a notable improvement, with a 15.1% increase in the power coefficient compared to the traditional Savonius turbine. This innovative approach not only extends the applicability of hydrokinetic turbines to low-flow regions but also underscores the potential of biomimicry in optimizing renewable energy technologies. The findings of this study indicate that integrating natural design principles can result in more efficient and sustainable energy solutions, thereby paving the way for the broader adoption of hydrokinetic power in diverse geographical settings. Full article

The present study is aimed at upgrading the passenger car’s front inner bumper. The dynamic explicit time-stepping method IMPACT was used to conduct the impact analysis. The programme was first evaluated against experimental findings for beams subjected to impacts at low loads. The deviation between the simulated and experimental findings of the deflected beam ranged from 1.6% to 9.5%. The genuine bumper was subjected to two different kinds of impact simulations. The data were used as a standard against which to compare future bumper improvements. Internal energy absorption is much higher in all the conditions. All three designs are able to absorb more energy without changing their overall performance. Full article

Electrical models play a crucial role in assessing the radiation sensitivity of devices. However, since they are usually not provided for end users, it is essential to have alternative modeling approaches to optimize circuit design before irradiation tests, and to support the understanding of post-irradiation data. This work proposes a novel simplified methodology to evaluate the single-event effects (SEEs) cross-section. To validate the proposed approach, we consider the 6T SRAM cell a case study in four technological nodes. The modeling considers layout features and the doping profile, presenting ways to estimate unknown parameters. The accuracy and limitations are determined by comparing our simulations with actual experimental data. The results demonstrated a strong correlation with irradiation data, without requiring any fitting of the simulation results or access to process design kit (PDK) data. This proves that our approach is a reliable method for calculating the single-event upset (SEU) cross-section for heavy-ion irradiation. Full article

Ionizing radiation induces the degradation of electronic systems. For memory devices, this phenomenon is often observed as the corruption of the stored data and, in some cases, the occurrence of sudden increases in current consumption during the operation. In this work, we propose enhanced experimental instrumentation to perform in-depth Single-Event Effects (SEE) monitoring and analysis of electronic systems. In particular, we focus on the Single-Event Latch-up (SEL) phenomena in memory devices, in which current monitoring and control are required for testing. To expose the features and function of the proposed instrumentation, we present results for a case study of an SRAM memory that has been used on-board PROBA-V ESA satellite. For this study, we performed experimental campaigns in two different irradiation facilities with protons and heavy ions, demonstrating the instrumentation capabilities, such as synchronization, high sampling rate, fast response time, and flexibility. Using this instrumentation, we could report the cross section for the observed SEEs and further investigate their correlation with the observed current behavior. Notably, it allowed us to identify that 95% of Single-Event Functional Interrupts (SEFIs) were triggered during SEL events. Full article

This work focuses on a capacitive biosensor based on a hydride peptide for the detection of MMP-13. Indeed, the enzyme MMP-13 is a remarkable indicator of inflammation in chronic wounds. To achieve specific detection of this enzyme, a metallocene was added to the peptide which amplifies the electrical variation allowing for proof of concept and reliability. Full article

This work explains that the Coulomb elastic process on the nucleus is a major source of single-event effects (SEE) for protons within the energy range of 1–10 MeV. The infinite range of Coulomb interactions implies an exceptionally high recoil probability. This research seeks to extend the investigations under which the elastic process becomes significant in the energy deposition process by providing a simplified methodology to evaluate the elastic contribution impact on the reliability of electronics. The goal is to derive a method to provide a simple way to calculate and predict the SEE cross-section. At very low energy, we observe a significant increase in the proton differential cross-section. The use of a direct Monte Carlo approach would mainly trigger low energy recoiling ions, and a very long calculation time would be necessary to observe the tail of the spectrum. In this sense, this work provides a simple methodology to calculate the SEE cross-section. The single-event upset (SEU) cross-section results demonstrate a good agreement with the experimental data in terms of shape and order of magnitude for different technological nodes. Full article

The aim of the present study was to provide a comprehensive summary of scientific evidence related with the influence on physical self-concept and prosocial behaviours in adolescents, taking into account the motivational climate generated in Physical Education classes by the teacher. Studies with similar samples have shown that special consideration must be given to the motivational climate of involvement with the task and the coach’s style in support of autonomy in a greater occurrence of prosocial behaviours in the sports context, which shows that the social context is the most important variable in the direction of moral behaviours. Following the application of a search protocol in the Web of Science (WoS) database, 131 articles were initially identified, with eight manuscripts finally being analysed according to previously established criteria for the various stages of the PRISMA checklist. Despite only a relatively small number of articles being available to have rigorously evaluated the topic of interest, analysed studies revealed a direct relationship between motivational climate and physical self-concept. In contrast, no relationship emerged with prosocial behaviour. Full article

“End of life” is a stage defined by the existence of an irreversible prognosis that ends with a person’s death. One of the aspects of interest regarding end of life focuses on parenteral nutrition, which is usually administered in order to avoid malnutrition and associated complications. However, parenteral nutrition can be adapted to specific circumstances and evolve in its functionality through supplementation with certain nutrients that can have a beneficial effect. This narrative review aims to carry out a situation analysis of the role that could be adopted by supplemental parenteral nutrition in attenuating alterations typical of end of life and potential improvement in quality of life. Full article