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The germination rate of pepper (Capsicum annuum L.) seeds is a key indicator of their vitality, which is complexly regulated by genetic and environmental factors. This study aims to elucidate the physiological and molecular mechanisms underlying the differences in germination rates among different pepper germplasm resources and identify the key genes regulating this trait. Three representative pepper materials (‘22HL6’, ‘22HL14’, ‘22HL2’) with significantly different germination rates were selected for this study. Key physiological and biochemical parameters during their germination process were systematically evaluated, including germination rate, vigor index, water absorption characteristics, amylase activity, antioxidant enzyme activity, and soluble sugar and protein content. Based on this, candidate genes related to germination rate were screened through transcriptome sequencing, and core candidate genes were preliminarily functionally validated using the Arabidopsis thaliana heterologous overexpression system. Materials with fast germination rates (‘22HL6’, ‘22HL14’) exhibited higher water absorption efficiency, amylase activity, antioxidant protection (such as lower MDA content and higher POD activity), and more active material metabolism (soluble sugar and protein) during the critical 72-h period. Transcriptome analysis successfully identified seven candidate genes closely related to germination rate. Among them, gene Capann_59V1aChr03g048850 had extremely high expression levels in fast-germinating materials but was almost not expressed in slow-germinating materials, and was identified as a core candidate gene. Heterologous overexpression of Capann_59V1aChr03g048850 in A. thaliana significantly promoted seed germination, with transgenic lines exhibiting earlier germination initiation, more developed taproot and lateral root systems, larger rosette diameter, and earlier bolting and flowering compared to wild-type plants. This study reveals the basis for the differences in germination rates of pepper seeds from the physiological and biochemical to molecular mechanism levels, and for the first time links the function of Capann_59V1aChr03g048850 gene to promoting seed germination and early seedling development. This gene provides valuable genetic resources for improving the germination uniformity and seedling vitality of pepper and even other crops through molecular breeding in the future. Full article

(This article belongs to the Section Horticultural and Floricultural Crops)

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22 pages, 3426 KB

Open AccessArticle

Study of Stability, Viscosity, and Thermal Diffusivity of SiC-HfC Hybrid Nanofluids in 50EG-50H₂O Mixture

by Caree A. García-Maro, Carmen S. Rochín-Wong, Laura G. Ceballos-Mendivil, José L. Jiménez-Pérez, Ruben Gutiérrez-Fuentes, Carlos A. Pérez-Rábago and Judith C. Tánori-Córdova

Fluids 2025, 10(12), 316; https://doi.org/10.3390/fluids10120316 (registering DOI) - 30 Nov 2025

Abstract

The growing global population has resulted in a higher demand for energy, leading researchers to prioritize the development of alternative energy sources and the improvement of current technologies. Nanofluids (NFs) are a promising method for enhancing heat transfer and efficiently utilizing solar thermal energy. This study describes the preparation of four NFs: two mono NFs of SiC and HfC containing nanoparticle concentrations ranging from 0.10–1.0 wt.%. Moreover, two hybrid NFs were synthesized within the same concentration range (0.10–1.0 wt.%) of SiC-HfC nanocomposites in proportions of 60 wt.% SiC-40 wt.% HfC and 40 wt.% SiC-60 wt.% HfC, all dispersed in a mixture of ethylene glycol (EG) and distilled water (50EG-50H₂O). The materials were synthesized by carbothermal reduction, and the NFs were prepared using the two-step method. The NFs showed stable dispersion, with HfC and 40SiC-60HfC systems exhibiting the higher zeta potential (ζ) values. Viscosity remained largely unaffected by particle addition. The thermal diffusivity of the NFs was measured by the thermal lens spectroscopy (TLS) technique using 1:20 diluted samples. The hybrid nanofluid 40SiC-60HfC improved diffusivity by 66.93%, presenting a synergistic effect in its performance, highlighting its potential in clean energy systems. Full article

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18 pages, 1835 KB

Open AccessArticle

Towards Robust Medical Image Segmentation with Hybrid CNN–Linear Mamba

by Xiao Ma and Guangming Lu

Electronics 2025, 14(23), 4726; https://doi.org/10.3390/electronics14234726 (registering DOI) - 30 Nov 2025

Abstract

Problem: Medical image segmentation faces critical challenges in balancing global context modeling and computational efficiency. While conventional neural networks struggle with long-range dependencies, Transformers incur quadratic complexity. Although Mamba-based architectures achieve linear complexity, they lack adaptive mechanisms for heterogeneous medical images and demonstrate insufficient local feature extraction capabilities. Method: We propose Linear Context-Aware Robust Mamba (LCAR–Mamba) to address these dual limitations through adaptive resource allocation and enhanced multi-scale extraction. LCAR–Mamba integrates two synergistic modules: the Context-Aware Linear Mamba Module (CALM) for adaptive global–local fusion, and the Multi-scale Partial Dilated Convolution Module (MSPD) for efficient multi-scale feature refinement. Core Innovations: CALM module implements content-driven resource allocation through four-stage processing: (1) analyzing spatial complexity via gradient and activation statistics, (2) computing allocation weights to dynamically balance global and local processing branches, (3) parallel dual-path processing with linear attention and convolution, and (4) adaptive fusion guided by complexity weights. MSPD module employs statistics-based channel selection and multi-scale partial dilated convolutions to capture features at multiple receptive scales while reducing computational cost. Key Results: On ISIC2017 and ISIC2018 datasets, mIoU improvements of 0.81%/1.44% confirm effectiveness across 2D benchmarks. On the Synapse dataset, LCAR–Mamba achieves 85.56% DSC, outperforming the former best Mamba baseline by 0.48% with 33% fewer parameters. Significance: LCAR–Mamba demonstrates that adaptive resource allocation and statistics-driven multi-scale extraction can address critical limitations in linear-complexity architectures, establishing a promising direction for efficient medical image segmentation. Full article

(This article belongs to the Special Issue Target Tracking and Recognition Techniques and Their Applications)

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15 pages, 541 KB

Open AccessArticle

Initial Compatibility Indicators of Four Coffea arabica Cultivars on Coffea canephora Rootstock

by Carlos Tuesta, Ligia García, Jorge Condori-Apfata, Eliana Alviárez-Gutierrez, Jaris Veneros, Grobert A. Guadalupe, Manuel Oliva-Cruz and Erick Arellanos

Horticulturae 2025, 11(12), 1449; https://doi.org/10.3390/horticulturae11121449 (registering DOI) - 30 Nov 2025

Abstract

Grafting is a strategy to mitigate biotic and abiotic stresses in coffee systems. However, initial compatibility indicators between Coffea arabica scions and C. canephora rootstocks under controlled conditions remain insufficiently documented. We evaluated the physiological and morphological compatibility of four C. arabica cultivars (Bourbon, Geisha, Catuai, and Villa Sarchí) grafted onto C. canephora (Robusta) rootstock in a tropical highland nursery in the Peruvian Amazon. Seven physiological and six morphological variables were measured. Statistical analyses included one-way ANOVA and Kruskal–Wallis tests with Bonferroni post hoc comparisons. Two physiological parameters were significantly higher in Villa Sarchí grafts than in Robusta: PSII quantum yield (+0.044 units; p < 0.05) and electron transport rate (+14.702 µmol e⁻ m⁻² s⁻¹; p < 0.05); by contrast, net photosynthesis, stomatal conductance, intercellular CO₂ concentration, and transpiration did not differ, and maximum PSII efficiency was similar among treatments (p = 0.509). Conversely, no morphological trait showed significant differences, and graft-take was high across all combinations. The results support the use of Coffea robusta as a rootstock for these four cultivated varieties, thereby offering the possibility of improving their resilience in tropical highland regions. Full article

(This article belongs to the Section Fruit Production Systems)

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25 pages, 950 KB

Open AccessSystematic Review

Physical Activity and the Optimization of Bone Mineral Density in Adolescents: A Systematic Review

by Yoel Antoranz, Manuel Ruiz Freire and Carlos Mª Tejero-González

Physiologia 2025, 5(4), 51; https://doi.org/10.3390/physiologia5040051 (registering DOI) - 30 Nov 2025

Abstract

Background/Objectives: Osteoporosis is a global health issue characterized by decreased bone mineral density (BMD), which increases the risk of fractures in adulthood. Adolescence, particularly the pubertal stage, is a critical period for maximizing BMD, and physical activity is a key modifiable factor in this process. The aim of this study was to conduct a systematic review of physical exercise interventions aimed at improving BMD in adolescents. Methods: The PRISMA methodology was applied, with searches conducted in PubMed, Web of Science, and SPORTDiscus. Included studies involved participants aged 11 to 18 years, structured physical activity interventions, and valid methods for assessing bone quality. Studies that included supplementation, lacked sufficient intervention details, or had no comparison group were excluded. Results: A total of 1464 articles were identified, of which 17 met the inclusion criteria and were analyzed. The results suggest that strength training programs and impact activities (such as football, volleyball, plyometric exercises, or running) appear to show benefits for bone development compared to control groups or non-osteogenic activities. The combination of strength and impact may reduce the time required to achieve measurable improvements. Non-osteogenic activities such as swimming and cycling showed no benefits on their own but may be beneficial when combined with resistance or impact training. The qualitative analysis indicates a certain risk of bias across the studies included. Conclusions: Although available evidence indicates that exercise programs involving strength or impact activities of around 8 months in duration and with a frequency of three sessions per week can be beneficial, these recommendations should be interpreted with caution due to the heterogeneity and limited number of studies, as well as the low certainty of the evidence. The combination of strength and impact exercises seems to shorten the intervention time required to achieve measurable improvements to approximately 6 months. These interventions appear to be most effective during early and middle adolescence, but current data do not consistently support sex-related differences. Full article

(This article belongs to the Section Exercise Physiology)

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14 pages, 4718 KB

Open AccessArticle

IL-5 and IP-10 Detected in Quantiferon Supernatants Distinguish Latent Tuberculosis from Healthy Individuals in Areas with High Burden in Lima, Peru

by Nawal De la Peña Galindo, Silvia Capristano Valdez, Cesar Sanchez Neira, Henri Bailon Calderon, Gilmer Solis Sanchez, Flor Peceros Pelaez and Marco Galarza Perez

Pathogens 2025, 14(12), 1225; https://doi.org/10.3390/pathogens14121225 (registering DOI) - 30 Nov 2025

Abstract

Background. Peru ranks among the countries with the highest burden of tuberculosis in Latin America. Interferon Gamma Release Assays (IGRAs), such as QuantiFERON-TB (QFT), cannot distinguish latent tuberculosis infection (LTBI) from active tuberculosis (ATB), but they provide a more specific and quantitative assessment of prior exposure to Mycobacterium tuberculosis. Methods. We enrolled 56 participants and measured 38 cytokines/chemokines from plasma obtained through QFT in patients with active TB (n = 11), LTBI (n = 17), and QFT-negative healthy controls (n = 28) using a Multiplex Bead Assay. Results. Levels of IL-1RA, IL-2, IL-5, IFN-γ, and IP-10 significantly differentiated both ATB and LTBI groups from healthy controls (p < 0.035). Furthermore, IL-5 and IP-10 specifically distinguished LTBI from healthy controls (p < 0.015), while GM-CSF differentiated ATB from controls (p < 0.05). Conclusions. Beyond IFN-γ as a differential proinflammatory cytokine in TB, cytokines such as IL-5, and IP-10 show potential as biomarkers to discriminate infection status in high-burden TB settings. Full article

(This article belongs to the Section Bacterial Pathogens)

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8 pages, 1138 KB

Open AccessCase Report

Influenza B-Associated Mild Encephalopathy with Reversible Splenial Lesion in an Adult: A Case Report

by Nicodemus Edrick Oey, Moe Pearl Shwe, Alvin Dingyuan Wang and Andrew Che Fai Hui

Neurol. Int. 2025, 17(12), 194; https://doi.org/10.3390/neurolint17120194 (registering DOI) - 30 Nov 2025

Abstract

Background/Objectives: Mild Encephalopathy with Reversible Splenial Lesion (MERS) is a potential complication of certain viral infections, but adult cases involving influenza are rare in the literature. Here, we report a case of a 31-year-old Chinese gentleman with an atypical presentation of Influenza B-associated mild encephalopathy with reversible splenial lesion (MERS). Methods: This is a case report with a detailed chronology followed by a discussion of pathophysiology. Results: The patient presented acutely to the tertiary hospital with a severe headache and a peculiar automatism pattern of behaviour involving intermittent screaming, involuntary jerking movements of the upper limbs, and incoherent speech, which culminated in an episode of tonic–clonic seizure lasting 3 min. Symptoms started on the day that the patient was diagnosed with Influenza B and given the antiviral Baloxavir by his GP. Clinically, there was high anion gap metabolic acidosis with hyperlactatemia, rhabdomyolysis, hepatitis transaminitis and absolute lymphopenia. Nasopharyngeal swab PCR and immunofluorescence was positive for Influenza B. EEG was normal, but an MRI of the brain showed a cytotoxic lesion of the splenium of the corpus callosum. The patient was started on Oseltamivir and made a complete neurological recovery, with a repeat MRI showing resolution of the splenial lesion at 3 months. MERS is a rare clinic-radiological syndrome characterized by a transient encephalopathy and a reversible lesion in the splenium of the corpus callosum, which has been reported mostly in the pediatric population. Conclusions: This case report of an influenza B-triggered MERS in an adult highlights the importance of maintaining MERS as a differential for acute encephalopathy in adults with a viral prodrome. Full article

(This article belongs to the Section Brain Tumor and Brain Injury)

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21 pages, 3923 KB

Open AccessArticle

New Insights on Fatigue Crack Growth of Reinforced Natural Rubber

by William Amoako Kyei-Manu, Lewis B. Tunnicliffe, Charles R. Herd, Keizo Akutagawa and James J. C. Busfield

Polymers 2025, 17(23), 3200; https://doi.org/10.3390/polym17233200 (registering DOI) - 30 Nov 2025

Abstract

The fatigue crack growth of natural rubber reinforced with various grades of carbon black has been studied across a wide range of tearing energies. Carbon blacks differ significantly in structure and surface area, influencing the mechanical and dynamic properties of the compounds. High-structure carbon black compounds exhibit an abrupt and significant step change in crack growth rate. Above the point of this step change, the different carbon black compounds have similar crack growth rates. Prior to this step change, high-structure carbon black compounds show a better crack growth resistance of up to two orders of magnitude compared to low-structure carbon black compounds. These step changes are attributed to strain-induced crystallisation effects. Before the step change, high-structure carbon black compounds nucleate and grow enough crystals at the crack tip to suppress crack growth. Above the step change, the crack tip velocity is too rapid for substantial strain-induced crystallisation to occur, as it is a time-dependent phenomenon. The step change aligns with the crack tip velocity where strain-induced crystallisation is reportedly absent. Understanding these step changes in crack growth can help rubber compounders design materials with improved crack growth resistance, leading to more durable components. Full article

(This article belongs to the Section Polymer Analysis and Characterization)

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Graphical abstract

52 pages, 636 KB

Open AccessArticle

Sequential Quantum Measurements and the Instrumental Group Algebra

by Christopher S. Jackson

Quantum Rep. 2025, 7(4), 57; https://doi.org/10.3390/quantum7040057 (registering DOI) - 30 Nov 2025

Abstract

Many of the most fundamental observables—position, momentum, phase point, and spin direction—cannot be measured by an instrument that obeys the orthogonal projection postulate. Continuous-in-time measurements provide the missing theoretical framework to make physical sense of such observables. The elements of the time-dependent instrument define a group called the instrumental group (IG). Relative to the IG, all of the time dependence is contained in a certain function called the Kraus-operator density (KOD), which evolves according to a classical Kolmogorov equation. Unlike the Lindblad master equation, the KOD Kolmogorov equation is a direct expression of how the elements of the instrument (not just the total quantum channel) evolve. Shifting from continuous measurements to sequential measurements more generally, the structure of combining instruments in sequence is shown to correspond to the convolution of their KODs. This convolution promotes the IG to an involutive Banach algebra (a structure that goes all the way back to the origins of POVM and C*-algebra theory), which will be called the instrumental group algebra (IGA). The IGA is the true home of the KOD, similar to how the dual of a von Neumann algebra is the true home of the density operator. Operators on the IGA, which play the analogous role for KODs as superoperators play for density operators, are called ultraoperators and various important examples are discussed. Certain ultraoperator–superoperator intertwining relationships are also considered throughout, including the relationship between the KOD Kolmogorov equation and the Lindblad master equation. The IGA is also shown to have actually two distinct involutions: one respected by the convolution ultraoperators and the other by the quantum channel superoperators. Finally, the KOD Kolmogorov generators are derived for jump processes and more general diffusive processes. Full article

18 pages, 1973 KB

Open AccessArticle

Ocular Toxicity and Mechanistic Investigation for Berberine and Its Metabolite Berberrubine on Zebrafish

by Ting Liu, Jia Tang, Xinyi Lu, Lu Jiang, Rui Zhang, Miaoqing Zhang, Jingpu Zhang, Danqing Song, Dousheng Zhang and Mingzhe Xu

Molecules 2025, 30(23), 4602; https://doi.org/10.3390/molecules30234602 (registering DOI) - 30 Nov 2025

Abstract

Berberine (BBR) has seen growing application in ophthalmology, yet the ocular toxicity of BBR and its metabolites remains poorly understood. This study aimed to evaluate the ocular toxicity of BBR and its major metabolite M1 and unravel their underlying mechanisms. Ocular toxicity was evaluated in human corneal epithelial cells and wild-type AB zebrafish. Mechanistic studies utilized fluorescence imaging, biochemical quantitative assays, and qPCR analyses in AB zebrafish and transgenic mitochondrial fluorescent zebrafish (strain Tg(Xla.Eef1a1:mlsEGFP)). Both BBR and M1 induced significant ocular toxicity across models, with BBR showing higher toxicity than M1. Mechanistic analyses revealed their toxicity stemmed from photoreceptor cell damage and Sirtuin 3 (SIRT3) inhibition, triggering a cascade of pathological events: mitochondrial dysfunction, oxidative stress, autophagic dysfunction, apoptosis, and inflammation. This study provides a reference for individualized risk assessment and clinical management of BBR-based therapies and paves the way for developing BBR derivatives with reduced ocular toxicity. Full article

(This article belongs to the Section Chemical Biology)

38 pages, 2935 KB

Open AccessArticle

Household Challenges in Solar Retrofitting to Optimize Energy Usage in Subtropical Climates

by Richard Hyde, David Wadley and John Hyde

Energies 2025, 18(23), 6312; https://doi.org/10.3390/en18236312 (registering DOI) - 30 Nov 2025

Abstract

This study investigates the architectural design factors that influence the adoption of eco-friendly solar energy technologies for the partial retrofitting of older residential buildings in densely populated urban areas in a developed country. This research study employs a mixed-method approach, combining quantitative and qualitative frameworks along with comparative analysis and utilizing standard fact-finding procedures to examine the adoption of eco-friendly energy systems and their integration into existing infrastructures. The feasibility study, complemented by a detailed technical investigation, identifies several significant factors affecting the intention to undertake sustainable solar retrofitting. These factors include performance expectations, facilitating conditions, motivation, price/value perceptions, and environmental knowledge. This study highlights key constraints and tipping points that influence households’ decisions to implement light retrofitting and explores three distinct system configurations to enhance cost-effectiveness. The insights gained from this research study are valuable for a range of stakeholders, including homeowners, designers, technology developers and manufacturers, real estate developers, builders, and government entities. The findings guide effective strategies to encourage eco-friendly retrofits through both passive and active systems, contributing to future environmental sustainability goals. This research study addresses a gap in the literature regarding the environmental sustainability of solar retrofitting in densely populated urban settings in developed countries. Addressing the pressing issue of global warming contributes to advancing sustainable solar housing technologies and provides a comprehensive foundation for the early stages of the design process. Full article

(This article belongs to the Special Issue Advanced Studies in Energy Efficiency of Buildings and Urban Built Environment)

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40 pages, 4617 KB

Open AccessArticle

Sustainability Assessment of Dry Reforming of Methane via Carbon Intensity and Syngas Energy Recovery Analysis

by Sheila Devasahayam, John Samuel Thella and Manoj K. Mohanty

Energies 2025, 18(23), 6307; https://doi.org/10.3390/en18236307 (registering DOI) - 30 Nov 2025

Abstract

This study conducts a comprehensive sustainability assessment of Dry Reforming of Methane (DRM), focusing on carbon intensity and syngas energy recovery (%) as primary performance indicators. By combining thermodynamic analysis with physics-informed machine learning (ML) models, DRM performance is evaluated across a range of operating conditions. Incorporating reaction enthalpy, carbon intensity, and syngas energy recovery as engineered features substantially improves model accuracy over baseline and kinetic models. Monte Carlo simulations are used to quantify uncertainty and identify robust operating windows, while techno-economic analysis benchmarks DRM against Steam Methane Reforming (SMR) and electrolysis. The results demonstrate that DRM can achieve syngas energy recovery values up to 190% and carbon intensity as low as 0.17, underscoring its promise as a competitive, low-carbon pathway for hydrogen and syngas production. Full article

(This article belongs to the Special Issue New Materials, Catalyst and Advances in Hydrogen Energy Production)

29 pages, 4278 KB

Open AccessArticle

Comprehensive Evaluation of the Integrated Operational Capability of the Former General Electric Power Companies in Japan Based on Entropy-TOPSIS–Coupling Coordination–Grey Correlation Degree

by Bingying Ma and Seiichi Ogata

Sustainability 2025, 17(23), 10732; https://doi.org/10.3390/su172310732 (registering DOI) - 30 Nov 2025

Abstract

The Former General Electric Utility in Japan is a major participant in the electricity market. The integrated operational capabilities of these power companies have significant impacts on the stable development and sustainability of the power industry. This study evaluates the comprehensive operational capabilities of these power companies from 2003 to 2015 and analyzes the indicators that may affect their operational capabilities. Establishing an evaluation index system comprising five subsystems, namely profitability, management, solvency, growth, and scale, and optimizing it using principal component analysis. The Technique for Order of Preference by Similarity to Ideal Solution was utilized to calculate the relative closeness of each company, with a score representing the integrated operational capabilities. Furthermore, coupling coordination and grey correlation analyses were conducted to assess the internal coordination among subsystems and to identify critical drivers of sustainable performance. The results show that (1) the Kyushu Electric Power Company and Tohoku Electric Power Company have strong integrated operational capabilities. (2) The five evaluation subsystems of integrated operational capability during the period of 2003–2015, fluctuated between moderate and high levels. (3) The top 5 indicators with the highest average grey correlation are as follows: “Hydropower capacity factor”, “Operating cash flow to current liabilities ratio”, “Operating profit growth rate”, “Net profit growth rate”, “Total capital utilization”. This study contributes to the sustainable management of the electricity industry by providing a systematic and data-driven assessment framework. The findings offer practical insights for optimizing corporate governance, enhancing energy efficiency, and formulating policy measures that support the long-term sustainability and competitiveness of Japan’s power utilities. Full article

(This article belongs to the Section Sustainable Management)

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25 pages, 7877 KB

Open AccessArticle

Intelligent Workshop Bearing Fault Diagnosis Method Based on Improved Convolutional Neural Network

by Xuan Su, Jitai Han, Chen Chen, Jingyu Lu, Weimin Ma and Xuesong Dai

Lubricants 2025, 13(12), 521; https://doi.org/10.3390/lubricants13120521 (registering DOI) - 30 Nov 2025

Abstract

A bearing intelligent fault diagnosis method based on an improved convolutional neural network is proposed to address the problems of high noise, difficult fault feature extraction, and low fault diagnosis recognition rate in rolling bearing vibration signals collected under complex working conditions. Firstly, in the data preprocessing stage, the wavelet denoising method is used to preprocess the data to obtain higher-quality signals. Then, the convolutional neural network LeNet-5 model was improved through batch normalization, Dropout, and L2 regularization methods. The wavelet denoised signal was input into the optimized LeNet-5 model to achieve more accurate fault diagnosis output for rolling bearings. Finally, to demonstrate the generalization ability of the model, this paper uses publicly available rolling bearing data from a university as the dataset and conducts experimental verification of the model using MATLAB software under different loads. The experimental results show that the improved neural network model has a fault diagnosis accuracy of 94.27%%, which is 17.84% higher than the traditional neural network model in terms of accuracy. Moreover, for different loads, the improved convolutional neural network model still maintains good fault diagnosis accuracy. Full article

36 pages, 5378 KB

Open AccessArticle

Hydrostatic Water Displacement Sensing for Continuous Biogas Monitoring

by Marek Habara, Jozef Molitoris, Barbora Jankovičová, Jan Rybář and Ján Vachálek

Sensors 2025, 25(23), 7297; https://doi.org/10.3390/s25237297 (registering DOI) - 30 Nov 2025

Abstract

Biogas and biomethane represent promising domestic fuels compatible with decarbonization targets at a time when diversification of gas sources is essential due to market volatility and increasing security risks. In laboratory practice, however, biogas production is still frequently assessed manually, which increases measurement uncertainty, limits temporal resolution, and reduces comparability between experimental series. We present an open and low-cost platform for continuous monitoring based on the hydrostatic water-displacement principle, complemented by stabilized process conditions (temperature control at 37 °C with short-term variability of approximately ±0.02 °C), continuous measurement with a 1 Hz sampling rate, and cloud-based data visualization. The methodology builds on a standardized procedure grounded in well-defined pressure–height–volume conversion relationships and transparent signal processing, enabling objective comparison of substrates and experimental setups. Validation experiments confirmed the system’s capability to capture short-term transient phenomena, improve reproducibility among parallel reactors, and maintain long-term measurement stability. Long-duration tests demonstrated short-term scatter of approximately 0.06 mL, minimal drift below 0.15% per 24 h, and an expanded uncertainty of roughly 3.1% at 100 mL. In parallel BMP tests, the continuous method yielded final volumes 5.78% higher than the discrete pressure method, reflecting systematic bias introduced by sparse manual sampling and reactor handling. The basic configuration quantifies the cumulative volume and production rate of biogas and is readily extendable to online gas composition analysis. The proposed solution offers a replicable tool for research and education, reduces costs, supports measurement standardization, and accelerates the optimization and subsequent scale-up of biogas technologies toward pilot-scale and industrial applications. Full article

(This article belongs to the Special Issue Feature Papers in the Internet of Things Section 2025)

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