Multidisciplinary Digital Publishing Institute (Switzerland)
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A Unified Benchmarking Framework for Classical Machine Learning Based Heart Rate Estimation from RGB and NIR rPPG
No full textThis work presents a unified benchmarking framework for evaluating classical machine-learning–based heart-rate estimation from remote photoplethysmography (rPPG) across both RGB and near-infrared (NIR) modalities. Despite extensive research on algorithmic rPPG methods, their relative robustness across datasets, illumination conditions, and sensor types remains inconsistently reported. To address this gap, we standardize ROI extraction, signal preprocessing, rPPG computation, handcrafted feature generation, and label formation across four publicly available datasets: UBFC-rPPG Part 1, UBFC-rPPG Part 2, VicarPPG-2, and IMVIA-NIR. We benchmark five rPPG extraction methods (Green, POS, CHROM, PBV, PCA/ICA) combined with four classical regressors using MAE, RMSE, and R2, complemented by permutation feature importance for interpretability. Results show that CHROM is consistently the most reliable algorithm across all RGB datasets, providing the lowest error and highest stability, particularly when paired with tree-based models. For NIR recordings, PCA with spatial patch decomposition substantially outperforms ICA, highlighting the importance of spatial redundancy when color cues are absent. While handcrafted features and classical regressors offer interpretable baselines, their generalization is limited by small-sample datasets and the absence of temporal modeling. The proposed pipeline establishes robust cross-dataset baselines and offers a standardized foundation for future deep-learning architectures, hybrid algorithmic–learned models, and multimodal sensor-fusion approaches in remote physiological monitoring
Synthesis, Optimization, and Evaluation of a New Sustained-Release Food Formulation for Polygonatum sibiricum Polysaccharide
No full textPolygonatum sibiricum polysaccharide (PsP), one of the main components of Polygonatumsibiricum used in traditional Chinese food and medicine, has important bioactive functions, but it is difficult to fully utilize PsP because of the degradative effect of digestive gastric juices. This study aimed to innovatively synthesize a new food formulation for PsP, namely, a PsP–hydroxyapatite (HAP) sustained-release system, so as to reduce its degradation. The new food formulation was optimized and evaluated by the response surface method (RSM) and by in vitro experiments. The optimal stirrer temperature, reaction pH, etching pH, and loading time for synthesizing PsP-HAP were 85.62 °C, pH 11.12, pH 8.40, and 5.10 h, respectively, all of which were different from the findings of other similar research studies. The average encapsulation rate of PsP-HAP reached (40.16 ± 1.54)%, and the content of PsP was 8.98%. Additionally, PsP-HAP appeared to be pH-responsive, and its continuous antioxidative effect was first proven by the DPPH assay and then cytologically by a total antioxidative capacity assay. The CCK-8 assay indicated that PSP-HAP did not induce toxicity. This study successfully developed a new food formulation for PsP which appears to have the potential to reduce the degradative effect of digestive gastric juices. Thus, it is possible to achieve full utilization of PsP by using this new sustained-release food formulation
Underwater Antenna Technologies with Emphasis on Submarine and Autonomous Underwater Vehicles (AUVs)
No full textFollowing the persistent evolution of terrestrial 5G wireless systems, a new field of underwater communication has emerged for various related applications like environmental monitoring, underwater mining, and marine research. However, establishing reliable high-speed underwater networks remains notoriously difficult due to the severe RF attenuation in conductive seawater, which strictly limits range coverage. In this article, we focus on a comprehensive review of different antenna types for future underwater communication and sensing systems, evaluating their performance and suitability for Autonomous Underwater Vehicles (AUVs). We critically examine and compare distinct antenna technologies, including Magnetic Induction (MI) coils, electrically short dipoles, wideband traveling wave antennas, printed planar antennas, and novel magnetoelectric (ME) resonators. Specifically, these antennas are compared in terms of physical footprint, operating frequency, bandwidth, and realized gain, revealing the trade-offs between miniaturization and radiation efficiency. Our analysis aims to identify the benefits and weaknesses of the different antenna types while emphasizing the necessity of innovative antenna designs to overcome the fundamental propagation limits of the underwater channel
Ubiquinol in Fertility and Reproduction: A Conditionally Essential Nutrient for Critical Early-Life Stages
No full textBackground/Objectives: Infertility is a multifactorial condition with an etiopathology that remains largely unclear. Although substantial evidence implicates oxidative stress (OS) as a key contributor to both male and female infertility, targeted strategies for OS-mediated reproductive dysfunction are still not well defined and require further investigation. Ubiquinol is the reduced form of Coenzyme Q10 involved in mitochondrial bioenergetics. It can be synthesized by humans endogenously or provided by dietary sources—typically egg yolks, oily fish, organ meats, and in smaller amounts in nuts and seeds and leafy green vegetables. The present article reviews possible mechanisms through which Ubiquinol plays a role in the regulation of fertility and reproduction, discussing why it could be positioned as a conditionally essential nutrient. Several questions and areas for further inquiry are also proposed. Methods: The present position paper narratively summarizes evidence related to Ubiquinol fertility and reproduction, focusing on the literature from PubMed, Science Direct, and Semantic Scholar. Results: Research advancements suggest that when physiological demands rise during certain life stages, e.g., the reproductive years, the amount of Ubiquinol produced internally may not be enough to meet heightened needs, particularly with advanced maternal/paternal age. This places a heavier reliance on obtaining Ubiquinol from the diet, thus presenting itself as a conditionally essential nutrient during certain life stages. Conclusions: Overall, Ubiquinol appears to enhance mitochondrial energy production and antioxidant defense in gametes, a process that appears to aid sperm function, oocyte quality, and early embryo development. Collectively, these data indicate a key physiological role for Ubiquinol in male and female fertility, especially given its age-related decline
Evaluating Greenery’s Contribution to Urban Thermal Comfort in Hot Arid Climates: A Systematic Review
No full textUrbanization and climate change have intensified the urban heat island (UHI) effect, increasing the demand for sustainable cooling solutions. Greenery, particularly in urban settings, has gained attention as a passive design strategy to enhance urban thermal comfort. This study systematically reviews peer-reviewed literature published in the last decade to assess the effectiveness of greenery in mitigating urban heat. Using a precise selection process, studies indexed in Web of Science (WOS), ScienceDirect, and Scopus were analyzed to identify key findings, methodologies, and gaps in existing research. The results highlight the impact of green facades, green walls, and urban greenery on surface and air temperature reduction, energy efficiency, and microclimate regulation. Furthermore, the study examines variations in performance based on climate zones, vegetation types, and urban configurations. Findings suggest that while greenery significantly improves urban thermal comfort, further research is needed to standardize assessment methods and optimize implementation strategies. This review contributes to the growing body of knowledge on nature-based solutions and provides insights for policymakers, urban designers, and researchers aiming to integrate greenery into sustainable urban planning
Discovery of the High-Affinity Aptamer for Candidalysin Using a Dual-Mode Colorimetric–SERS Platform
No full textCandida albicans poses significant health risks through its virulent peptide toxin Candidalysin. As no existing therapeutics specifically target this toxin, developing high-affinity aptamers for its efficient and safe removal is urgently needed. In response, we developed a dual-mode biosensor based on gold nanoparticles (AuNPs) and aptamers for screening high-affinity aptamers for Candidalysin. This biosensor leverages the localized surface plasmon resonance (LSPR) phenomenon and surface-enhanced Raman scattering (SERS) of AuNPs to detect changes in color and Raman signals, respectively, indicative of high-affinity aptamer for Candidalysin presence. This dual-mode capability reduces false-negative signals and enhances detection accuracy. Our findings reveal a specific aptamer with high affinity for Candidalysin, presenting a significant advancement in candidiasis treatment. This work sets the stage for the development of effective therapeutic strategies against Candida infections
Screw-Type Shredder for Solid Photopolymer Resin in Microgravity Environments
No full textThe invention concerns a screw-driven shredder for solid photopolymer resin, designed for both terrestrial use and prospective deployment in microgravity environments. The system addresses the need for efficient recycling of cured photopolymer waste generated by stereolithography (SLA) 3D printing—a process not yet implemented in orbit, but envisioned as part of future closed-loop additive manufacturing systems aboard space stations or lunar habitats. The proposed device is a compact, hermetically sealed mechanical unit composed of ten subassemblies, featuring two counter-rotating screw shafts equipped with carbide milling inserts arranged helically to achieve uniform and controlled fragmentation of solid SLA residues. The shredding process is supported by a pressurized inert fluid circuit, utilizing carbon dioxide (CO2) as a cryogenic working medium to enhance cutting efficiency, reduce heat accumulation, and ensure particle evacuation under microgravity conditions. Studies indicate that CO2-assisted cooling can reduce tool-tip temperature by 10–30 °C, cutting forces by 5–15%, and electrical power consumption by 5–12% while extending tool life by up to 50%. This invention thus provides a key component for a future in situ photopolymer recycling loop in space while also offering a high-efficiency shredding solution for Earth-based photopolymer waste management in additive manufacturing
Evaluating Middleware Performance in the Transition from Monolithic to Microservices Architecture for Banking Applications
No full textThe swift development of digital financial services has increased transaction volumes and heightened system performance requirements. Cardless cash deposit transactions at PT Bank XYZ have significantly increased since 2022. This growth necessitates an evaluation and improvement of the existing system architecture. This study proposes a microservices-based architecture deployed in a middleware environment to enhance performance, scalability, and availability. Key enhancements include asynchronous service processing, dual-layer authentication, and data caching using the Terracotta Server Array. The evaluation uses metrics such as CPU usage, RAM usage, latency, throughput, error rate, success rate, and recovery time. Both the monolithic and microservice architectures were assessed through stress testing. Tools used include Red Hat OpenShift Dashboard, NMon Visualizer, and Apache JMeter. Results indicate that the microservices architecture outperforms the monolithic architecture by delivering better resource efficiency, lower latency, higher throughput, and faster recovery times. Moreover, implementing dual-layer authentication enhances security without significantly increasing system complexity. The findings confirm the long-term viability of the microservices architecture for high-demand financial applications
Endothelial Activation and Stress Index (EASIX) Predicts In-Hospital Mortality in Acute Decompensated Heart Failure with Reduced Ejection Fraction
No full textBackground: Early risk stratification in acute decompensated heart failure with reduced ejection fraction (ADHF-rEF) remains challenging. The Endothelial Activation and Stress Index (EASIX)—a composite of lactate dehydrogenase, creatinine, and platelet count—reflects endothelial dysfunction, a pathophysiological contributor to early deterioration in ADHF-rEF. This study evaluated the prognostic utility of admission-based EASIX for in-hospital mortality. Methods: In this retrospective single-center cohort, 850 consecutive patients hospitalized with ADHF-rEF between January 2022 and June 2025 were analyzed. EASIX was calculated from first-day laboratory values. Logistic regression, ROC analysis, restricted cubic splines, and Kaplan–Meier survival methods were used to assess the association between EASIX and in-hospital mortality, and to evaluate its incremental value beyond established clinical and laboratory predictors. Results: In-hospital mortality was 12.4%. Higher EASIX values were significantly associated with mortality in both univariable and multivariable models (adjusted OR 1.273; p < 0.001). EASIX demonstrated moderate discriminative performance among evaluated biomarkers (AUC 0.751) and showed a clear dose–response risk gradient, with mortality rising from 1.4% in the lowest tertile to 26.2% in the highest. Incorporating EASIX into clinical and laboratory prediction models yielded substantial continuous net reclassification improvement (0.59 and 0.38, respectively). Survival curves diverged early and remained distinctly separated across EASIX strata. Conclusions: Admission EASIX is an independent predictor of in-hospital mortality in ADHF-rEF and provides complementary prognostic information beyond conventional models. This is the first study to demonstrate the prognostic value of EASIX in the ADHF-rEF setting, supporting its potential utility as an accessible endothelial stress biomarker for early risk stratification
LoRa Power Model for Energy Optimization in IoT Applications
No full textEnergy efficiency is a key requirement for Internet of Things (IoT) nodes, particularly in applications powered by energy harvesting that operate without batteries. In this work, we present a parametric power model of a LoRa transceiver (Semtech SX1276) aimed at ultra-low power remote sensing scenarios. The transceiver was characterized in all relevant states (startup, transmission, reception, and sleep), and the results were used to build a state-based model that predicts average power consumption as a function of transmission power, sleep strategy, packetization, and input data rate. Experimental validation confirmed that the cubic fit for transmission peaks achieves a determination coefficient of 0.99, while reception is added as a constant consumption. The model was implemented in a Python simulator that provides mean, best-case, and worst-case estimates of system power consumption, and it was validated in an ASIC-based sensor node demonstration, with predictions within 10% of measured values. The framework highlights the trade-offs between energy efficiency and robustness (e.g., minimal SF and no CRC vs. higher spreading factors and error-control) and supports the design of custom controllers for ultra-low power IoT nodes as well as more energy-permissive applications