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16 pages, 2498 KB  
Article
Nanoparticles Enhance in Vitro Micropropagation and Secondary Metabolite Accumulation in Origanum petraeum
by Tamara S. Al Qudah, Rida A. Shibli, Rund Abu-Zurayk and Mohammad Hudaib
Nanomaterials 2025, 15(19), 1496; https://doi.org/10.3390/nano15191496 - 30 Sep 2025
Abstract
Origanum petraeum Danin, an endemic medicinal shrub from Jordan, belongs to the Lamiaceae family and possesses significant pharmaceutical potential, yet its secondary metabolite profile remains largely unexplored. This study evaluated the effects of two types of nanoparticles, silver (Ag) and copper (Cu), on [...] Read more.
Origanum petraeum Danin, an endemic medicinal shrub from Jordan, belongs to the Lamiaceae family and possesses significant pharmaceutical potential, yet its secondary metabolite profile remains largely unexplored. This study evaluated the effects of two types of nanoparticles, silver (Ag) and copper (Cu), on in vitro propagation and secondary metabolite composition in O. petraeum microshoots. Sterilized buds were used to initiate in vitro cultures on Murashige and Skoog (MS) medium supplemented with gibberellic acid (GA3) at 0.5 mg/L. Microshoots were treated with nanoparticles at concentrations of 0, 25, 50, 100, and 150 mg/L. AgNPs at 100 mg/L promoted growth, increasing the number of microshoots to 11.6 and shoot height to 9.22 cm. Transmission electron microscopy confirmed nanoparticle uptake and translocation, with AgNPs observed in root cells as small particles (≤24.63 nm), while CuNPs formed aggregates in leaves (47.71 nm). GC-MS analysis revealed that nanoparticles altered the volatile composition; 50 mg/L CuNPs enhanced monoterpenes, including α-terpinyl acetate (29.23%) and geranyl acetate (12.76%), whereas 50 mg/L AgNPs increased sesquiterpenes, such as caryophyllene oxide (28.45%). Control in vitro cultures without nanoparticles showed simpler profiles dominated by caryophyllene oxide, while wild plants contained both monoterpenes and sesquiterpenes, with eudesm-7(11)-en-4-ol (25.10%) as the major compound. Nutrient analysis indicated that nanoparticles influenced nutrient composition in microshoots. This study is the first to report nanoparticle-assisted growth and essential oil composition in O. petraeum, demonstrating their potential to enhance growth and secondary metabolite production for pharmacological and biotechnological applications. Full article
(This article belongs to the Section Nanotechnology in Agriculture)
16 pages, 4491 KB  
Article
New Methodology for Evaluating Uncertainty in Mineral Resource Estimation
by José Alberto Arias, Alain Carballo, Elmidio Estévez, Reinaldo Rojas, Domingo A. Martín and Jorge L. Costafreda
Appl. Sci. 2025, 15(19), 10616; https://doi.org/10.3390/app151910616 - 30 Sep 2025
Abstract
Geological modeling is generally based on deterministic models, which provide a single representation of reality. Probabilistic modeling is more appropriate when quantifying or understanding the uncertainty associated with a parameter of interest as it considers several equally probable geological scenarios. The object of [...] Read more.
Geological modeling is generally based on deterministic models, which provide a single representation of reality. Probabilistic modeling is more appropriate when quantifying or understanding the uncertainty associated with a parameter of interest as it considers several equally probable geological scenarios. The object of this study is to quantify the uncertainty in the estimation of the minerals in the Punta Alegre gypsum deposit, by applying a new method based on the simple normal equation geostatistical simulation technique. The Punta Alegre gypsum deposit is a sedimentary deposit of clastic origin, formed by the complex redeposition of salts, gypsum and other sediments. To carry out this research, 50 equiprobable scenarios were simulated, reproducing overburden, gypsum series (different types of gypsum) and intercalated non-mineral lithologies (limestone and other rocks) in a network of nodes measuring 5 × 5 × 5 m, using a training image, composites and prior probability maps as input data. As a result of scaling the previously simulated geological units, three-dimensional models of volume proportions and estimation error for gypsum were obtained for panels measuring 10 × 10 × 5 m. The quantification of the uncertainty of the gypsum volume, determined by the root mean square error, established that the volume estimation error is small at a global scale (6.51%), given that there is no significant variation when comparing the deterministic model with the gypsum proportion model obtained from the 50 simulated scenarios. Conversely, at the local scale, there is a significant variation in gypsum volume of 42% in the 10 × 10 × 5 m panels with a future impact on recoverable mining resources, given the uncertainty at a local scale, which will cause an increase in mining dilution due to the inclusion of non-mineral lithologies within the extracted mineral that will be sent to the processing plant. On the other hand, it will cause changes in the mining company’s plan in areas where there are panels that were previously accounted for by the deterministic model as minerals and are not actually exploitable. Full article
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20 pages, 2968 KB  
Article
Tensile Modeling PVC Gels for Electrohydraulic Actuators
by John Albert Faccinto, Jongcheol Lee and Kwang J. Kim
Polymers 2025, 17(19), 2641; https://doi.org/10.3390/polym17192641 - 30 Sep 2025
Abstract
Polyvinyl chloride (PVC)-dibutyl adipate (DBA) gels are a fascinating dielectric elastomer actuator showing promise in soft robotics. When actuated with high voltages, the gel deforms towards the anode. A recent application of PVC gels in electrohydraulic actuators motivates elastic and hyperelastic constitutive relationships [...] Read more.
Polyvinyl chloride (PVC)-dibutyl adipate (DBA) gels are a fascinating dielectric elastomer actuator showing promise in soft robotics. When actuated with high voltages, the gel deforms towards the anode. A recent application of PVC gels in electrohydraulic actuators motivates elastic and hyperelastic constitutive relationships for tensile loading modes. PVC gels with plasticizer-to-polymer weight ratios of 2:1, 4:1, 6:1, and 8:1 w/w were evaluated. PVC gels exhibit a linear elastic region up to 25% strain. The elastic modulus decreased with increasing plasticizer content from 288.8 kPa, 56.1 kPa, 24.7 kPa, to 11 kPa. Poisson’s ratio also decreased with increasing plasticizer content from 0.42, 0.43, 0.39, to 0.35. We suggest that the decrease in polymer concentration facilitates a weakly interconnected polymer network susceptible to chain slippage that hinders the network response, thus lowering Poisson’s ratio. Our work suggests that PVC gels can be treated as isotropic and incompressible for large strains and hyperelastic modeling; however, highly plasticized gels tend to act less incompressible at small strains. The power scaling law between the elastic modulus and plasticizer weight ratio showed high agreement, making the elastic modulus deterministic for any plasticizer content. The Neo–Hookean, Mooney–Rivlin, Yeoh, Gent, Ogden, and extended tube hyperelastic constitutive models are investigated. The Yeoh model shows the highest feasibility when evaluated up to 3.5 stretch, showing a maximum normalized root-mean-square-error of 6.85%. Together, these findings establish a constitutive basis for PVC-DBA gels, incorporating small strain elasticity, large strain non-linear behavior, and network analysis while providing suggestive insight into the network structure required for accurately modeling the EPIC. Full article
(This article belongs to the Special Issue Polymeric Materials in Optoelectronic Devices and Energy Applications)
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20 pages, 4998 KB  
Technical Note
Design and Implementation of a Small-Scale Hydroponic Chamber for Sustainable Vegetative Propagation from Cuttings: A Basil (Ocimum basilicum L.)
by Angélica Nohemí Cardona Rodríguez, Carlos Alberto Olvera-Olvera, Santiago Villagrana-Barraza, Ma. Auxiliadora Araiza-Ezquivel, Diana I. Ortíz-Esquivel, Luis Octavio Solís-Sánchez and Germán Díaz-Flórez
Sustainability 2025, 17(19), 8773; https://doi.org/10.3390/su17198773 - 30 Sep 2025
Abstract
Urban agriculture in space-constrained cities requires compact, reproducible propagation systems. Therefore, the aim of this Technical Note is to design, implement, and functionally validate a low-cost, modular hydroponic chamber (SSHG) for early-stage vegetative propagation. This system couples DHT11-based temperature/RH monitoring with rule-based actuation—irrigation [...] Read more.
Urban agriculture in space-constrained cities requires compact, reproducible propagation systems. Therefore, the aim of this Technical Note is to design, implement, and functionally validate a low-cost, modular hydroponic chamber (SSHG) for early-stage vegetative propagation. This system couples DHT11-based temperature/RH monitoring with rule-based actuation—irrigation 4×/day and temperature-triggered ventilation—under the control of an Arduino Uno microcontroller; LED lighting was not controlled nor analyzed. Two 15-day trials with basil (Ocimum basilicum L.) yielded rooting rates of 61.7% (37/60) and 43.3% (26/60) under a deliberate minimal-input configuration without nutrient solutions or rooting hormones. Environmental summaries and spatial survival maps revealed edge-effect patterns and RH variability that inform irrigation layout improvements. The chamber, bill of materials, and protocol are documented to support replication and iteration. Thus, the SSHG provides a transferable baseline for educators and researchers to audit, reproduce, and improve small-footprint, controlled-environment propagation. Beyond its technical feasibility, the SSHG contributes to sustainability by leveraging low-cost, readily available components, enabling decentralized seedling production in space-constrained settings, and operating under a minimal-input configuration. In line with widely reported hydroponic efficiencies (e.g., lower water use relative to soil-based propagation), this open and replicable platform aligns with SDGs 2, 11, 12, and 13. Full article
(This article belongs to the Section Sustainable Agriculture)
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27 pages, 10042 KB  
Article
CFD Study of a Novel Wave Energy Converter in Survival Mode
by Cassandre Senocq, Daniel Clemente, Mailys Bertrand, Paulo Rosa-Santos and Gianmaria Giannini
Energies 2025, 18(19), 5189; https://doi.org/10.3390/en18195189 - 30 Sep 2025
Abstract
Harnessing Europe’s strong wave energy could support net-zero emissions goals, but extreme ocean loads still make wave energy expensive and delay the rollout of commercial wave-energy converters (WECs). To address this, the twin-floater CECO WEC has been redesigned into a single-pivot device called [...] Read more.
Harnessing Europe’s strong wave energy could support net-zero emissions goals, but extreme ocean loads still make wave energy expensive and delay the rollout of commercial wave-energy converters (WECs). To address this, the twin-floater CECO WEC has been redesigned into a single-pivot device called the Pivoting WEC (PWEC), which includes a passive duck diving survival mode to reduce extreme wave impacts. Its performance is evaluated using detailed wave simulations based on Reynolds-Averaged Navier–Stokes (RANS) equations and the Volume-of-Fluid (VoF) method in OpenFOAM-olaFlow, which is validated with data from small-scale (1:20) wave tank experiments. Extreme non-breaking and breaking waves are simulated based on 100-year hindcast data for the case study site of Matosinhos (Portugal) using a modified Miche criterion. These are validated using data of surface elevation and force sensors. Wave height errors averaged 5.13%, and period errors remain below 0.75%. The model captures well major wave loads with a root mean square error down to 47 kN compared to a peak load of 260 kN and an R2 up to 0.80. The most violent plunging waves increase peak forces by 5 to 30% compared to the highest non-breaking crests. The validated numerical approach provides accurate extreme load predictions and confirms the effectiveness of the PWEC’s passive duck diving survival mode. The results contribute to the development of structurally resilient WECs, supporting the progress of WECs toward higher readiness levels. Full article
(This article belongs to the Special Issue Advancements in Marine Renewable Energy and Hybridization Prospects)
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28 pages, 7493 KB  
Article
Research on Frequency Characteristic Fitting of LLC Switching-Mode Power Supply Under All Operating Conditions Based on FT-WOA-MLP
by Jiale Guo, Rongsheng Han, Zibo Yang, Guoqing An, Rui Li and Long Zhang
J. Low Power Electron. Appl. 2025, 15(4), 57; https://doi.org/10.3390/jlpea15040057 - 28 Sep 2025
Abstract
The frequency characteristics of the switching-mode power supply (SMPS) control loop under all operating conditions are crucial for performance evaluation and defect detection. Traditional methods, relyingon experiments under preset conditions, struggle to achieve comprehensive evaluation. This study proposes a frequency characteristic fitting method [...] Read more.
The frequency characteristics of the switching-mode power supply (SMPS) control loop under all operating conditions are crucial for performance evaluation and defect detection. Traditional methods, relyingon experiments under preset conditions, struggle to achieve comprehensive evaluation. This study proposes a frequency characteristic fitting method for all operating conditions based on FT-WOA-MLP. A discrete-point dataset covering all conditions of an LLC SMPS was obtained using the small-signal perturbation method, including input voltage, output current, injection frequency, and corresponding amplitude- and phase-frequency characteristics. The multilayer perceptron (MLP) model was trained on the training set covering all operating conditions, with the whale optimization algorithm (WOA) used to optimize the learning rate, and fine tuning (FT) applied to further enhance accuracy. Independent test set validation showed that, for amplitude-frequency characteristics, the mean absolute error (MAE) was 2.0995, the mean absolute percentage error (MAPE) was 0.0974, the root mean square error (RMSE) was 4.0474, and the coefficient of determination (R2) reached 0.92; for phase-frequency characteristics, the MAE was 3.502, the MAPE was 0.0956, the RMSE was 10.5192, and the R2 reached 0.94. The method accurately fits frequency characteristics under all conditions, supporting defect identification and performance optimization. Full article
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31 pages, 10644 KB  
Article
An Instance Segmentation Method for Agricultural Plastic Residual Film on Cotton Fields Based on RSE-YOLO-Seg
by Huimin Fang, Quanwang Xu, Xuegeng Chen, Xinzhong Wang, Limin Yan and Qingyi Zhang
Agriculture 2025, 15(19), 2025; https://doi.org/10.3390/agriculture15192025 - 26 Sep 2025
Abstract
To address the challenges of multi-scale missed detections, false positives, and incomplete boundary segmentation in cotton field residual plastic film detection, this study proposes the RSE-YOLO-Seg model. First, a PKI module (adaptive receptive field) is integrated into the C3K2 block and combined with [...] Read more.
To address the challenges of multi-scale missed detections, false positives, and incomplete boundary segmentation in cotton field residual plastic film detection, this study proposes the RSE-YOLO-Seg model. First, a PKI module (adaptive receptive field) is integrated into the C3K2 block and combined with the SegNext attention mechanism (multi-scale convolutional kernels) to capture multi-scale residual film features. Second, RFCAConv replaces standard convolutional layers to differentially process regions and receptive fields of different sizes, and an Efficient-Head is designed to reduce parameters. Finally, an NM-IoU loss function is proposed to enhance small residual film detection and boundary segmentation. Experiments on a self-constructed dataset show that RSE-YOLO-Seg improves the object detection average precision (mAP50(B)) by 3% and mask segmentation average precision (mAP50(M)) by 2.7% compared with the baseline, with all module improvements being statistically significant (p < 0.05). Across four complex scenarios, it exhibits stronger robustness than mainstream models (YOLOv5n-seg, YOLOv8n-seg, YOLOv10n-seg, YOLO11n-seg), and achieves 17/38 FPS on Jetson Nano B01/Orin. Additionally, when combined with DeepSORT, compared with random image sampling, the mean error between predicted and actual residual film area decreases from 232.30 cm2 to 142.00 cm2, and the root mean square error (RMSE) drops from 251.53 cm2 to 130.25 cm2. This effectively mitigates pose-induced random errors in static images and significantly improves area estimation accuracy. Full article
(This article belongs to the Section Artificial Intelligence and Digital Agriculture)
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21 pages, 2235 KB  
Article
Root Growth and Branching of Two Cycas Species Are Influenced by Form of Nitrogen Fertilizer
by Thomas E. Marler
Agronomy 2025, 15(10), 2280; https://doi.org/10.3390/agronomy15102280 - 26 Sep 2025
Abstract
Horticultural research into the group of plants known as cycads has been deficient, and this includes the study of root growth and function. The form of nitrogen (N) available to plants is known to influence root growth and morphology. The response of cycad [...] Read more.
Horticultural research into the group of plants known as cycads has been deficient, and this includes the study of root growth and function. The form of nitrogen (N) available to plants is known to influence root growth and morphology. The response of cycad roots to N has not been studied to date. Cycas revoluta and Cycas edentata seedlings were grown in hydroponic culture and provided urea, nitrate, or ammonium forms of N. Solutions with all three forms of N increased root growth and branching when compared with nutrient solution devoid of N, with ammonium eliciting the greatest increases. Ammonium increased lateral root length 210% for C. revoluta and 164% for C. edentata. Ammonium decreased specific root length 38% for C. revoluta and 39% for C. edentata. The influence of the N source on stem and leaf growth was minimal. Ammonium increased the root-to-shoot ratio 15% for C. revoluta and 51% for C. edentata, but urea and nitrate did not influence this plant trait. A mixture of nitrate and ammonium generated plant responses that were no different from ammonium alone. The plants supplied with N in the solution produced coralloid root growth that was 14% of the no-N plants for C. revoluta and 22% of the no-N plants for C. edentata. This initial determination of the cycad plant response to the N form indicated that root plasticity was considerable and ammonium stimulated root growth more so than urea or nitrate. Long-term growth studies in mineral soils and nursery container medium are needed to determine if these findings from the hydroponic culture of small seedlings translate to general recommendations for the preferential use of ammonium for cycad culture. Full article
(This article belongs to the Section Soil and Plant Nutrition)
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42 pages, 2586 KB  
Review
Telehealth as a Sociotechnical System: A Systems Analysis of Adoption and Efficacy Among Older Adults Post-COVID-19
by Md Golam Rabbani, Ashrafe Alam and Victor R. Prybutok
Systems 2025, 13(10), 843; https://doi.org/10.3390/systems13100843 - 25 Sep 2025
Abstract
Framed within the lens of systems theory and sociotechnical systems thinking, this systematic review examines telehealth as a complex adaptive system and dynamic health system shaped by the interactions between interconnected technological, social, and institutional components. Recognizing telehealth as part of a complex [...] Read more.
Framed within the lens of systems theory and sociotechnical systems thinking, this systematic review examines telehealth as a complex adaptive system and dynamic health system shaped by the interactions between interconnected technological, social, and institutional components. Recognizing telehealth as part of a complex adaptive system, the review identifies how interdependent factors, such as digital literacy, connectivity, and policy, evolve and influence access to and the emergent properties of care. A systematic review was conducted following the PRISMA 2020 guidelines and PROSPERO registration (CRD420251103608), analyzing 42 peer-reviewed articles published between January 2020 and June 2025, identified through the MEDLINE, Web of Science, EBSCOhost, ACM Digital Library, PsycINFO, and Scopus databases. Key findings include sustained but reduced telehealth use after the pandemic peak, as well as a small yet statistically significant positive effect of telehealth interventions on cognitive emergent properties, defined here as measurable outcomes like memory, attention, executive function, and processing speed (SMD = 0.29; 95% CI [0.04, 0.54]) with very low heterogeneity (I2 = 0%). Significant system components such as digital illiteracy, poor internet connectivity, and complex technology interfaces disproportionately affected economically disadvantaged, minority, and rural older adults. Practical strategies rooted in systems thinking include digital literacy programs, simplified interfaces, caregiver support, improved broadband infrastructure, hybrid healthcare models, and supportive policies. Future research should focus on evidence-based, system-level interventions across diverse settings to bridge the digital divide and promote equitable access to telehealth for older adults. Full article
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19 pages, 2073 KB  
Article
Precision Design Method for Superplastic Forming Process Parameters Based on an Improved Back Propagation Neural Network
by Xiaoke Guo, Wanran Yang, Qian Zhang, Junchen Pan, Chengyue Xiong and Le Wu
Processes 2025, 13(10), 3070; https://doi.org/10.3390/pr13103070 - 25 Sep 2025
Abstract
A significant contradiction exists between the demand for standardized processes and the need for precise process parameter design in the rapid design of superplastic forming (SPF). To address this, an SPF process parameter design method integrating a knowledge graph and artificial intelligence is [...] Read more.
A significant contradiction exists between the demand for standardized processes and the need for precise process parameter design in the rapid design of superplastic forming (SPF). To address this, an SPF process parameter design method integrating a knowledge graph and artificial intelligence is proposed. Firstly, based on process data analysis, the entity labels, relationship categories, and attributes are determined. On this basis, the knowledge graph for the SPF process is constructed, comprising the pattern layer and the data layer, which provides structured knowledge support for process generation. Secondly, the process parameter prediction model based on small samples and an improved back propagation (BP) neural network is constructed, with model convergence ensured through an adaptive maximum iteration strategy. Experimental results show that the improved BP model significantly outperforms support vector regression (SVR), random forest (RF), extreme gradient boosting (XGBoost), and standard BP models in prediction accuracy. Compared to the standard BP model, the improved model reduces the mean squared error (MSE), mean absolute error (MAE), and root mean squared error (RMSE) by 82.1% (to 0.0005), 46% (to 0.0188), and 57.1% (to 0.0229), respectively. Finally, the effectiveness, feasibility, and superiority of the method in the SPF process parameter design are verified by taking typical hemispherical parts as an example. Full article
(This article belongs to the Section Manufacturing Processes and Systems)
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27 pages, 4687 KB  
Article
Comparative Study of Vibration-Based Machine Learning Algorithms for Crack Identification and Location in Operating Wind Turbine Blades
by Adolfo Salgado-Ancona, Perla Yazmín Sevilla-Camacho, José Billerman Robles-Ocampo, Juvenal Rodríguez-Reséndiz, Sergio De la Cruz-Arreola and Edwin Neptalí Hernández-Estrada
AI 2025, 6(10), 242; https://doi.org/10.3390/ai6100242 - 25 Sep 2025
Abstract
The growing energy demand has increased the number of wind turbines, raising the need to monitor blade health. Since blades are prone to damage that can cause severe failures, early detection is crucial. Machine learning-based monitoring systems can identify and locate cracks without [...] Read more.
The growing energy demand has increased the number of wind turbines, raising the need to monitor blade health. Since blades are prone to damage that can cause severe failures, early detection is crucial. Machine learning-based monitoring systems can identify and locate cracks without interrupting energy production, enabling timely maintenance. This study provides a comparative analysis and approach to the application and effectiveness of different vibration-based machine learning algorithms to detect the presence of cracks, identify the cracked blade, and locate the zone where the crack occurs in rotating blades of a small wind turbine. The datasets comprise root vibration signals, derived from healthy and cracked blades of a wind turbine in operational conditions. In this study, the blades are not considered identical. The sampling set dimension and the number of features were variables considered during the development and assessment of different models based on decision tree (DT), support vector machine (SVM), k-nearest neighbors (KNN), and multilayer perceptron algorithms (MLP). Overall, the KNN models are the clear winners in terms of training efficiency, even as the sample size increases. DT is the most efficient algorithm in terms of test speed, followed by SVM, MLP, and KNN. Full article
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39 pages, 4559 KB  
Article
Effects of Biases in Geometric and Physics-Based Imaging Attributes on Classification Performance
by Bahman Rouhani and John K. Tsotsos
J. Imaging 2025, 11(10), 333; https://doi.org/10.3390/jimaging11100333 - 25 Sep 2025
Abstract
Learned systems in the domain of visual recognition and cognition impress in part because even though they are trained with datasets many orders of magnitude smaller than the full population of possible images, they exhibit sufficient generalization to be applicable to new and [...] Read more.
Learned systems in the domain of visual recognition and cognition impress in part because even though they are trained with datasets many orders of magnitude smaller than the full population of possible images, they exhibit sufficient generalization to be applicable to new and previously unseen data. Since training data sets typically represent such a small sampling of any domain, the possibility of bias in their composition is very real. But what are the limits of generalization given such bias, and up to what point might it be sufficient for a real problem task? There are many types of bias as will be seen, but we focus only on one, selection bias. In vision, image contents are dependent on the physics of vision and geometry of the imaging process and not only on scene contents. How do biases in these factors—that is, non-uniform sample collection across the spectrum of imaging possibilities—affect learning? We address this in two ways. The first is theoretical in the tradition of the Thought Experiment. The point is to use a simple theoretical tool to probe into the bias of data collection to highlight deficiencies that might then deserve extra attention either in data collection or system development. Those theoretical results are then used to motivate practical tests on a new dataset using several existing top classifiers. We report that, both theoretically and empirically, there are some selection biases rooted in the physics and imaging geometry of vision that challenge current methods of classification. Full article
(This article belongs to the Section Computer Vision and Pattern Recognition)
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57 pages, 12419 KB  
Article
The Learning Rate Is Not a Constant: Sandwich-Adjusted Markov Chain Monte Carlo Simulation
by Jasper A. Vrugt and Cees G. H. Diks
Entropy 2025, 27(10), 999; https://doi.org/10.3390/e27100999 - 25 Sep 2025
Abstract
A fundamental limitation of maximum likelihood and Bayesian methods under model misspecification is that the asymptotic covariance matrix of the pseudo-true parameter vector θ* is not the inverse of the Fisher information, but rather the sandwich covariance matrix [...] Read more.
A fundamental limitation of maximum likelihood and Bayesian methods under model misspecification is that the asymptotic covariance matrix of the pseudo-true parameter vector θ* is not the inverse of the Fisher information, but rather the sandwich covariance matrix 1nA*1B*1A*1, where A* and B* are the sensitivity and variability matrices, respectively, evaluated at θ* for training data record ω1,,ωn. This paper makes three contributions. First, we review existing approaches to robust posterior sampling, including the open-faced sandwich adjustment and magnitude- and curvature-adjusted Markov chain Monte Carlo (MCMC) simulation. Second, we introduce a new sandwich-adjusted MCMC method. Unlike existing approaches that rely on arbitrary matrix square roots, eigendecompositions or a single scaling factor applied uniformly across the parameter space, our method employs a parameter-dependent learning rate λ(θ) that enables direction-specific tempering of the likelihood. This allows the sampler to capture directional asymmetries in the sandwich distribution, particularly under model misspecification or in small-sample regimes, and yields credible regions that remain valid when standard Bayesian inference underestimates uncertainty. Third, we propose information-theoretic diagnostics for quantifying model misspecification, including a strictly proper divergence score and scalar summaries based on the Frobenius norm, Earth mover’s distance, and the Herfindahl index. These principled diagnostics complement residual-based metrics for model evaluation by directly assessing the degree of misalignment between the sensitivity and variability matrices, A* and B*. Applications to two parametric distributions and a rainfall-runoff case study with the Xinanjiang watershed model show that conventional Bayesian methods systematically underestimate uncertainty, while the proposed method yields asymptotically valid and robust uncertainty estimates. Together, these findings advocate for sandwich-based adjustments in Bayesian practice and workflows. Full article
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14 pages, 3611 KB  
Article
Performance Comparison of LSTM and ESN Models in Time-Series Prediction of Solar Power Generation
by Yehan Joo, Dogyoon Kim, Youngmin Noh, Jaewon Choi and Jonghwan Lee
Sustainability 2025, 17(19), 8538; https://doi.org/10.3390/su17198538 - 23 Sep 2025
Viewed by 169
Abstract
Improving the prediction accuracy of solar power generation is a critical challenge in promoting sustainable energy solutions. While machine learning models like long short-term memory (LSTM) have gained attention, they face practical limitations such as their complex structure, long training time, and susceptibility [...] Read more.
Improving the prediction accuracy of solar power generation is a critical challenge in promoting sustainable energy solutions. While machine learning models like long short-term memory (LSTM) have gained attention, they face practical limitations such as their complex structure, long training time, and susceptibility to overfitting. Echo state networks (ESNs) have attracted attention for their small number of trainable parameters and fast training speed, but their sensitivity to hyperparameter settings makes performance improvement difficult. In this study, the key hyperparameters of an ESN (spectral radius, input noise, and leakage rate) were optimized to maximize performance. The ESN achieved a Root Mean Square Error (RMSE) of 0.0069 for power prediction, demonstrating a significant improvement in accuracy over a tuned LSTM model. ESNs are also well-suited for real-time prediction and large-scale data processing, owing to their low computational cost and fast training speed. By providing a more accurate and efficient forecasting tool, this study supports grid operators in managing the intermittency of renewable energy, thereby fostering a more stable and reliable sustainable energy infrastructure. Full article
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21 pages, 2608 KB  
Article
Molecular Insights into Ammonium Sulfate-Induced Secretome Reprogramming of Bacillus subtilis Czk1 for Enhanced Biocontrol Against Rubber Tree Root Rot
by Yanqiong Liang, Shibei Tan, Ying Lu, Helong Chen, Xing Huang, Kexian Yi, Chunping He and Weihuai Wu
Microorganisms 2025, 13(9), 2212; https://doi.org/10.3390/microorganisms13092212 - 21 Sep 2025
Viewed by 208
Abstract
Root rot diseases caused by Ganoderma pseudoferreum and Pyrrhoderma noxium inflict substantial economic losses in rubber tree (Hevea brasiliensis) cultivation, while conventional control methods face environmental and resistance challenges. This study aimed to specifically investigate the molecular mechanisms by which ammonium [...] Read more.
Root rot diseases caused by Ganoderma pseudoferreum and Pyrrhoderma noxium inflict substantial economic losses in rubber tree (Hevea brasiliensis) cultivation, while conventional control methods face environmental and resistance challenges. This study aimed to specifically investigate the molecular mechanisms by which ammonium sulfate enhances the biocontrol efficacy of Bacillus subtilis Czk1. Using label-free quantitative proteomics (LC-MS/MS), we characterized ammonium sulfate-induced alterations in the secretory proteome of Czk1. A total of 351 differentially expressed proteins (DEPs) were identified, with 329 significantly up-regulated and 22 down-regulated. GO functional enrichment analysis indicated that up-regulated DEPs were associated with metabolic pathways (glyoxylate/dicarboxylate, arginine/proline, cofactor biosynthesis) and extracellular localization (13 proteins), while down-regulated DEPs were linked to small molecule catabolism. KEGG pathway annotation identified DEP involvement in 124 pathways, including secondary metabolite biosynthesis and membrane transport. These findings demonstrate that ammonium sulfate remodels the Czk1 secretome to enhance the expression of key antagonistic proteins, thereby providing crucial molecular targets and a scientific foundation for developing effective biofungicides against rubber root rot, with clear practical implications for sustainable disease management. Full article
(This article belongs to the Section Plant Microbe Interactions)
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