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12 pages, 70638 KiB

Open AccessCommunication

Land Drainage Interventions for Climate Change Adaptation: An Overlooked Phenomenon—A Conceptual Case Study from Northern Bohemia, Czech Republic

by Jiří Černý, Petr Fučík and Antonín Zajíček

Land 2025, 14(4), 782; https://doi.org/10.3390/land14040782 (registering DOI) - 5 Apr 2025

Abstract

This study investigates the often-overlooked phenomenon of land drainage interventions as a means of climate change adaptation, focusing on a conceptual case study from Northern Bohemia, Czech Republic. The intensification of agriculture has led to extensive tile drainage systems, which have had significant [...] Read more.

This study investigates the often-overlooked phenomenon of land drainage interventions as a means of climate change adaptation, focusing on a conceptual case study from Northern Bohemia, Czech Republic. The intensification of agriculture has led to extensive tile drainage systems, which have had significant environmental impacts, including disruption of water balance, nutrient leaching, and ecological degradation. With climate change expected to alter precipitation patterns and increase temperatures, these impacts are likely to intensify, leading to more frequent droughts and pollutant delivery from soil to water bodies. This study explores the options for the allocation and implementation of drainage-related measures such as controlled drainage, constructed wetlands, and partial drainage elimination to mitigate these effects, with the use of readily available archival data as well as aerial images, current as well as historical soil, land use, geomorphological and landowner-land user relationships. At two cadastral units with local potable water resources at the hilly Lovečkovicko case study, the paper proposes conceptual, practical approaches for integrating drainage-related measures into land consolidation processes. Here, eleven sites based on the cross-intersection of the above interventions’ criteria were selected, and twenty various drainage-related measures were tentatively designed. This study categorizes the implementation potential of the proposed measures into three levels: high, medium, and low, highlighting the feasibility and transferability of these interventions within the land consolidation or similar process. Full article

(This article belongs to the Special Issue Nature-Based Solutions for Soil-Water Related Sustainable Development Goals)

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30 pages, 7078 KiB

Open AccessArticle

Enhancement of Mechanical and Tribological Properties of MWCNT-Reinforced Bio-Based Epoxy Composites Through Optimization and Molecular Dynamics Simulation

by Pavan Hiremath, Y. M. Shivaprakash, Kiran Keshyagol, Suhas Kowshik, B. M. Gurumurthy, D. V. Ghewade, Shivashankarayya Hiremath and Nithesh Naik

J. Compos. Sci. 2025, 9(4), 176; https://doi.org/10.3390/jcs9040176 (registering DOI) - 5 Apr 2025

Abstract

This study investigated the enhancement of the mechanical and tribological properties of MWCNT-reinforced bio-based epoxy composites through systematic experiments and analysis. Composites incorporating MWCNTs at varying weight percentages were evaluated for hardness, wear rate, interfacial shear strength, and friction coefficient under diverse load, [...] Read more.

This study investigated the enhancement of the mechanical and tribological properties of MWCNT-reinforced bio-based epoxy composites through systematic experiments and analysis. Composites incorporating MWCNTs at varying weight percentages were evaluated for hardness, wear rate, interfacial shear strength, and friction coefficient under diverse load, sliding speed, and distance conditions. An optimal MWCNT content of 0.3–0.4% resulted in a maximum hardness of 4 GPa and a minimum wear rate of 0.0058 mm³/N·m, demonstrating a substantial improvement over the non-reinforced system. FTIR and XRD analyses confirmed robust interfacial bonding between the MWCNTs and epoxy matrix, while molecular dynamics simulations revealed cohesive energy density and stress distribution profiles. The Taguchi optimization identified the MWCNT weight percentage as the most influential parameter, contributing over 85% to wear rate reduction. Contour plots and correlograms further illustrate the parameter interdependencies, emphasizing the role of MWCNT dispersion in enhancing the composite properties. These findings establish that MWCNT-reinforced bio-based epoxy composites are promising candidates for high-performance and sustainable tribological applications. Full article

(This article belongs to the Special Issue Characterization and Modeling of Composites, 4th Edition)

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20 pages, 5003 KiB

Open AccessArticle

Assessment of Mercury Contamination in the Chalk Aquifer of the Pays de Caux and Its Implications for Public Health (France)

by Lahcen Zouhri, Jacques Delépine and Lockman Zouhri

Water 2025, 17(7), 1087; https://doi.org/10.3390/w17071087 (registering DOI) - 5 Apr 2025

Abstract

Mercury is naturally present in soils at trace concentrations, but its cycle is increasingly disrupted by anthropogenic activities, which affect its distribution and behavior. Due to its toxic nature, mercury has become a significant focus in environmental and public health policies. Following the [...] Read more.

Mercury is naturally present in soils at trace concentrations, but its cycle is increasingly disrupted by anthropogenic activities, which affect its distribution and behavior. Due to its toxic nature, mercury has become a significant focus in environmental and public health policies. Following the detection of mercury anomalies during groundwater quality monitoring at the Pays de Caux study site (France), a comprehensive multidisciplinary research effort was initiated. This included geological and hydrogeological studies aimed at tracking mercury concentrations in piezometric wells and identifying the sources of these anomalies. This study seeks to assess the groundwater quality and characteristics from ten hydrogeological wells. The evaluation will focus on key hydrogeological parameters, including pH, redox potential (Eh), suspended solids, and groundwater levels, as well as a detailed geochemical analysis of elements such as Hg, Fe, Mn, Zn, Pb, and Cu. The mobilization of mercury and other metallic traces elements is strongly governed by environmental factors. Hydrochemical analyses highlight the complex interplay of various parameters that influence the chemical forms and behavior of mercury in both soil and groundwater. The results from the piezometric measurement campaigns (Pz1 to Pz7) have provided crucial insights, enabling the development of hypotheses about mercury’s behavior in the chalk aquifer. It is hypothesized that impermeable areas may trap groundwater for extended periods, leading to the accumulation and abnormal concentration of mercury. This could cause mercury to be intermittently released, potentially affecting the surrounding environment. Mercury concentrations in groundwater are highly sensitive to pH and redox potential (Eh), with low pH and reducing conditions promoting mercury mobilization and the formation of toxic methylated species. The study suggests the chalk aquifer is generally in equilibrium with mercury, but fluctuations in mercury levels between Pz7 and Pz4 are likely due to the heterogeneity of the clay and geological factors such as mineral composition and fracturing. This research provides insights into mercury transfer in heterogeneous environments and emphasizes the need for continuous hydrogeological monitoring, including piezometer readings, to manage mercury dispersion in the aquifer. Full article

(This article belongs to the Section Hydrology)

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14 pages, 1314 KiB

Open AccessArticle

SAA1 Protein: A Potential Biomarker for Acute Myeloid Leukemia

by Pedro Leite Azevedo, Mayara Rezende, Milena Felix, Stephany Corrêa, Eliana Abdelhay and Renata Binato

Biomedicines 2025, 13(4), 880; https://doi.org/10.3390/biomedicines13040880 (registering DOI) - 5 Apr 2025

Abstract

Background/Objectives: Despite its heterogeneity and diagnostic challenges, acute myeloid leukemia (AML) originates from stem cell transformation and alterations in the hematopoietic niche (HN) could be related to leukemic transformation. Therefore, the aim of this study was to evaluate the protein profile of HN [...] Read more.

Background/Objectives: Despite its heterogeneity and diagnostic challenges, acute myeloid leukemia (AML) originates from stem cell transformation and alterations in the hematopoietic niche (HN) could be related to leukemic transformation. Therefore, the aim of this study was to evaluate the protein profile of HN from AML patients and compare it with the profile of healthy donors (HDs). Methods: A proteomic analysis was conducted to identify differentially expressed (DE) proteins in BM plasma from AML patients and HD. In silico analysis was performed to identify biological processes and signaling pathways involved. Additionally, ELISA confirmed the expression of the DE protein of interest in BM plasma samples. Results: Proteomic analysis revealed alterations in the plasma profiles of AML patients and 36 DE proteins were found. Among then, we highlight C8G, CFB, SAA1, SERPINA3 and SERPINC1, which are related to inflammatory response process. Thus, considering the role of the secreted protein SAA1 in the inflammatory context and that it is described as a potential biomarker in several tumors, we selected SAA1 for ELISA confirmation. The results corroborated our findings, indicating that increased expression of SAA1 could be related to AML. Our results also revealed that SAA1 can stimulate immune signaling through NF-kappa-B activation. Conclusions: These findings position SAA1 as a promising biomarker for AML diagnosis, offering a potential tool for more accurate identification of the disease. Nevertheless, further studies are needed to understand the relationship of SAA1 with the leukemic transformation process in AML and its potential clinical use. Full article

(This article belongs to the Section Cancer Biology and Oncology)

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20 pages, 5041 KiB

Open AccessArticle

Effects of Drainage Technology on Waterlogging Reduction and Rice Yield in Mid-Lower Reaches of Yangtze River

by Bowei Qi, Shenjiao Yang, Dongwei Li, Dandan Qin, Xingfei Zheng, Jianlin Hu, Xinguo Zhou and Hongquan Liu

Agronomy 2025, 15(4), 905; https://doi.org/10.3390/agronomy15040905 (registering DOI) - 5 Apr 2025

Abstract

As extreme rainfall events become more frequent, leading to increased waterlogging hazards, it is crucial to explore various drainage methods that can alleviate the adverse effects of waterlogging on crop growth, thus addressing challenges related to global food security. Field experiments were carried [...] Read more.

As extreme rainfall events become more frequent, leading to increased waterlogging hazards, it is crucial to explore various drainage methods that can alleviate the adverse effects of waterlogging on crop growth, thus addressing challenges related to global food security. Field experiments were carried out to evaluate the impacts of different drainage technologies on waterlogging mitigation, rice growth, dry matter accumulation, and yield. The experimental setup included varying straw blind ditch spacings (2, 3, 4, and 5 m) and subsurface pipe drainage spacings (6, 9, and 12 m), with surface drainage serving as the control (CK). The findings revealed that, in comparison to pipe drainage treatments, blind ditch treatments enhanced subsurface drainage volume by 15.1%. Regarding groundwater levels and soil moisture, the soil moisture in the 0–90 cm soil layer and groundwater levels under the blind ditch treatments were 11.3% and 6.1% lower than those under the CK as well as 22.0% and 23.9% lower than the pipe drainage treatments, respectively. Subsurface drainage treatments led to significant improvements in rice yield, with blind ditch and pipe drainage treatments increasing the yield by 8.0% and 6.0% compared to the CK. Rice yields initially increased before decreasing as burial spacing reduced. The S3 treatment resulted in yield increases of 14.4%, 8.6%, and 10.7% over the S2, S4, and S5 treatments, respectively. The G9 treatment produced 3.6% and 10.4% higher yields compared to the G6 and G12 treatments. The highest rice yield, 7.501 Mg·ha⁻¹, was achieved with a blind ditch spacing of 3 m. Compared to the S4 and S5 treatments, the yield per hectare for the S3 treatment was higher by 0.592 Mg and 0.726 Mg, while the input cost was higher by CNY 3038 and 4560, respectively. Path analysis indicated that root biomass made the largest direct contribution (0.517) to the increase in rice yield. Subsurface drainage contributed to the regulation of soil moisture, reducing leaf biomass while increasing stem biomass, which enabled the blind ditch treatments to produce optimal rice yield. These results provide a scientific basis for agricultural drainage in waterlogged areas. Full article

(This article belongs to the Special Issue Agricultural Water Management and Non-Point Source Contamination Mitigation)

16 pages, 2405 KiB

Open AccessArticle

Real World Posaconazole Pharmacokinetic Data in Paediatric Stem Cell Transplant Recipients

by Csaba Kassa, Katalin Csordás, Lídia Hau, Orsolya Horváth, Krisztián Kállay, Gabriella Kertész, Márton Kiss, János Sinkó, Ágnes Wolfort and Gergely Kriván

Children 2025, 12(4), 467; https://doi.org/10.3390/children12040467 (registering DOI) - 5 Apr 2025

Abstract

Background: Invasive fungal disease is a significant cause of morbidity and mortality in allogeneic hematopoietic stem cell transplant (alloHSCT) recipients. Posaconazole, a broad-spectrum triazole, is widely used as prophylaxis. Methods: We conducted a monocentric, retrospective study to present real-world data on posaconazole trough [...] Read more.

Background: Invasive fungal disease is a significant cause of morbidity and mortality in allogeneic hematopoietic stem cell transplant (alloHSCT) recipients. Posaconazole, a broad-spectrum triazole, is widely used as prophylaxis. Methods: We conducted a monocentric, retrospective study to present real-world data on posaconazole trough levels in paediatric alloHSCT patients. The main objective was to determine the required daily dose of posaconazole in paediatric patients. We analysed factors influencing posaconazole levels, and the association between posaconazole levels and breakthrough fungal infection. Results: Among 102 allogeneic HSCT recipients, we measured posaconazole plasma concentrations in 548 blood samples. The required daily doses to reach a target range of 0.7–2.0 mg/L were 15.22 (suspension), 7.52 (tablet), and 7.84 mg/kg (intravenous). Patients aged < 13 years needed higher doses to achieve the target range. The presence of enteral symptoms during prophylaxis was associated with lower plasma concentrations (p < 0.001), while co-administration of proton pump inhibitors did not (p = 0.09). Eight breakthrough infections occurred; low levels of posaconazole (<0.7 mg/L) were observed in five out of eight cases. The Cox regression model showed that higher mean plasma concentrations decreased the hazard of breakthrough infections. Conclusions: The tablet and intravenous formulations of posaconazole outperformed the suspension in terms of predictability. Our analyses on breakthrough infections and posaconazole plasma levels suggest an exposure–response relationship. Full article

(This article belongs to the Special Issue The Diagnosis and Management of Pediatric Leukemia)

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25 pages, 6987 KiB

Open AccessArticle

Feasibility and Mechanical Performance of 3D-Printed Polymer Composite External Fixators for Tibial Fractures

by Ion Badea, Tudor-George Alexandru and Diana Popescu

Appl. Sci. 2025, 15(7), 4007; https://doi.org/10.3390/app15074007 (registering DOI) - 5 Apr 2025

Abstract

This study evaluates the feasibility of 3D-printed polymer composite external fixator (EF) rings as a cost-effective alternative to stainless steel fixators, focusing on hybrid fixators for complex tibial fractures. Mechanical performance was assessed in three stages: (1) evaluating the initial EF–tibia configuration under [...] Read more.

This study evaluates the feasibility of 3D-printed polymer composite external fixator (EF) rings as a cost-effective alternative to stainless steel fixators, focusing on hybrid fixators for complex tibial fractures. Mechanical performance was assessed in three stages: (1) evaluating the initial EF–tibia configuration under axial loading and wire pre-tension conditions; (2) analyzing the stiffness evolution and weight-bearing capacity during early healing with progressive callus formation; and (3) optimizing ring designs through numerical analysis to improve structural performance under increased pre-tension. The results showed that, for the metallic EF, the axial displacement under one-leg stance reached 8.41 mm without pre-tension, reducing to 6.83 mm at 500 N pre-tension, though transverse displacement remained significant, suggesting the need for higher wire tension. Callus formation enhanced the load-bearing capacity, as expected. However, excessive displacements persisted under the one-leg stance, indicating that full weight-bearing should be delayed beyond two weeks for a fracture gap of 3 mm. A ring design assessment showed that full-ring configurations with two wires per ring improved performance. The 3D-printed full-ring design made of carbon-fiber-reinforced polylactic acid (PLA-CF) reduced stress by 85% at 500 N pre-tension compared to the initial configuration, remaining within allowable limits. While confirming feasibility, the study highlights the need for geometric refinements to accommodate higher preloads and improve transverse stiffness. Full article

(This article belongs to the Section Additive Manufacturing Technologies)

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13 pages, 4500 KiB

Open AccessArticle

(1→3)-α-d-Glucan from the Pink Oyster Mushroom (Pleurotus djamor): Structural Features

by Paulina Adamczyk, Iwona Komaniecka, Marek Siwulski, Kamila Wlizło, Adam Junka, Artur Nowak, Dariusz Kowalczyk, Adam Waśko, Jolanta Lisiecka, Michał Grzymajło and Adrian Wiater

Foods 2025, 14(7), 1272; https://doi.org/10.3390/foods14071272 (registering DOI) - 5 Apr 2025

Abstract

(1→3)-α-d-Glucan is an important component of the cell wall of most fungi. The polymer has many applications, including as a therapeutic agent in the prevention or treatment of various diseases, as well as a heavy metal sorbent and a component of [...] Read more.

(1→3)-α-d-Glucan is an important component of the cell wall of most fungi. The polymer has many applications, including as a therapeutic agent in the prevention or treatment of various diseases, as well as a heavy metal sorbent and a component of new materials used in the plastics industry. The presence of (1→3)-α-d-glucan (water-insoluble, alkali-soluble polysaccharide) in the cell wall of Pleurotus djamor (pink oyster mushroom) was confirmed using specific fluorophore-labeled antibodies. Therefore, the water-insoluble fraction (WI-ASF) of P. djamor B123 fruiting bodies was isolated by alkaline extraction and used for further analyses. The structural features of the WI-ASF were determined by composition analysis, linkage analysis, Fourier transform infrared and Raman spectroscopy, ¹H and ¹³C nuclear magnetic resonance spectroscopy, scanning electron microscopy, as well as viscosity, specific rotation, and gel permeation chromatography. These studies revealed the presence of glucose units linked by α-glycosidic bonds and scanty amounts of mannose and xylose. Furthermore, methylation analysis of WI-ASF demonstrated that the (1→3)-linked glucopyranose (Glcp) is the primary moiety (86.4%) of the polymer, while the 3,4- and 3,6-substituted hexoses are the branching residues of the glucan. The results of chemical and spectroscopic investigations indicated that the analyzed WI-ASF is a (1→3)-linked α-d-glucan type with a molecular weight of 552 kDa. Full article

(This article belongs to the Special Issue Edible Fungi: Processing, Storage Preservation, Disease Control, and Potential Bioactivities)

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14 pages, 613 KiB

Open AccessArticle

Exploratory Algorithms to Aid in Risk of Malignancy Prediction for Indeterminate Pulmonary Nodules

by Laurel Jackson, Claire Auger, Nicolette Jeanblanc, Christopher Jacobson, Kinnari Pandya, Susan Gawel, Hita Moudgalya, Akanksha Sharma, Christopher W. Seder, Michael J. Liptay, Ramya Gaddikeri, Nicole M. Geissen, Palmi Shah, Jeffrey A. Borgia and Gerard J. Davis

Cancers 2025, 17(7), 1231; https://doi.org/10.3390/cancers17071231 (registering DOI) - 5 Apr 2025

Abstract

Background/Objectives: Lung cancer screening can reduce patient mortality. Multiple issues persist including timely management of patients with a radiologically defined indeterminate pulmonary nodule (IPN), which carries unknown pathological significance. This pilot study focused on combining demographic, clinical, radiographic, and common circulating biomarkers for [...] Read more.

Background/Objectives: Lung cancer screening can reduce patient mortality. Multiple issues persist including timely management of patients with a radiologically defined indeterminate pulmonary nodule (IPN), which carries unknown pathological significance. This pilot study focused on combining demographic, clinical, radiographic, and common circulating biomarkers for their ability to aid in IPN risk of malignancy prediction. Methods: A case-control cohort consisting of 379 patients with IPNs (251 stage I lung tumors and 128 nonmalignant nodules) was used for this effort, divided into training (70%) and testing (30%) sets. Demographic variables (age, sex, race, ethnicity), radiographic information (nodule size and location), smoking pack-years, and plasma biomarker levels of CA-125, SCC, CEA, HE4, ProGRP, NSE, Cyfra 21-1, IL-6, PlGF, sFlt-1, hs-CRP, Ferritin, IgG, IgE, IgM, IgA, and Kappa and Lambda Free Light Chains were assessed for this purpose. Results: Multivariable analyses of biomarker, demographic, and radiographic variables yielded a model consisting of age, lesion size, pack-years, history of extrathoracic cancer, upper lobe location, spiculation, hs-CRP, NSE, Ferritin, and CA-125 (AUC = 0.872 in training, 0.842 in testing) with superior performance over the Mayo Score model, which consists of age, lesion size, history of smoking, history of extrathoracic cancer, upper lobe location, and spiculation (AUC = 0.816 in training, 0.787 in testing). Conclusions: In conclusion, a simple reduced algorithm consisting of biomarkers, clinical information, and demographic variables may have value for malignancy prediction of screen-detected IPNs. Upon further validation, this method stands to reduce the need for serial radiographic studies and the risks of diagnostic delay. Full article

(This article belongs to the Special Issue Predictive Biomarkers for Lung Cancer)

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17 pages, 7128 KiB

Open AccessArticle

Application of Deep Learning on Global Spaceborne Radar and Multispectral Imagery for the Estimation of Urban Surface Height Distribution

by Vivaldi Rinaldi and Masoud Ghandehari

Remote Sens. 2025, 17(7), 1297; https://doi.org/10.3390/rs17071297 (registering DOI) - 5 Apr 2025

Abstract

Digital Surface Models (DSMs) have a wide range of applications, including the spatial and temporal analysis of human habitation. Traditionally, DSMs are generated by rasterizing Light Detection and Ranging (LiDAR) point clouds. While LiDAR provides high-resolution details, the acquisition of required data is [...] Read more.

Digital Surface Models (DSMs) have a wide range of applications, including the spatial and temporal analysis of human habitation. Traditionally, DSMs are generated by rasterizing Light Detection and Ranging (LiDAR) point clouds. While LiDAR provides high-resolution details, the acquisition of required data is logistically challenging and costly, leading to limited spatial coverage and temporal frequency. Satellite imagery, such as Synthetic Aperture Radar (SAR), contains information on surface height variations in the scene within the reflected signal. Transforming satellite imagery data into a global DSM is challenging but would be of great value if those challenges were overcome. This study explores the application of a U-Net architecture to generate DSMs by coupling Sentinel-1 SAR and Sentinel-2 optical imagery. The model is trained on surface height data from multiple U.S. cities to produce a normalized DSM (NDSM) and assess its ability to generalize inferences for cities outside the training dataset. The analysis of the results shows that the model performs moderately well when inferring test cities but its performance remains well below that of the training cities. Further examination, through the comparison of height distributions and cross-sectional analysis, reveals that estimation bias is influenced by the input image resolution and the presence of geometric distortion within the SAR image. These findings highlight the need for refinement in preprocessing techniques as well as advanced training approaches and model architecture that can better handle the complexities of urban landscapes encoded in satellite imagery. Full article

(This article belongs to the Section AI Remote Sensing)

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18 pages, 4480 KiB

Open AccessArticle

Physiological and Biochemical Measurements Reveal How Styrax japonica Seedlings Response to Flooding Stress

by Gaoyuan Zhang, Jinghan Dong, Chao Han, Zemao Liu, Jianbing Liu and Fangyuan Yu

Forests 2025, 16(4), 634; https://doi.org/10.3390/f16040634 (registering DOI) - 5 Apr 2025

Abstract

This study investigated the physiological and biochemical responses of Styrax japonica Sieb. et Zucc. seedlings to normal water and nutrient management (control group, CK), waterlogging (root submerged, T1), and partial submergence (partial stem submergence, T2) over a period of 25 days. Measurements of [...] Read more.

This study investigated the physiological and biochemical responses of Styrax japonica Sieb. et Zucc. seedlings to normal water and nutrient management (control group, CK), waterlogging (root submerged, T1), and partial submergence (partial stem submergence, T2) over a period of 25 days. Measurements of root activity, malondialdehyde (MDA) content, hydrogen peroxide (H₂O₂) content, antioxidant enzyme (SOD, POD, and CAT), and anaerobic respiratory enzyme (LDH, ADH, and PDC) activities were conducted every 5 days. The results showed the following: the seedlings of the control group maintained high root activity and low oxidative damage levels throughout the experiment; under T1 treatment, root activity initially increased but declined, while MDA and H₂O₂ content gradually increased; T2 seedlings showed little change initially, but root activity briefly increased at Day 20 before rapidly declining. Regarding the antioxidant system, the control group had the highest SOD activity, while seedlings under T1 and T2 treatments exhibited compensatory upregulation of CAT and POD activities (from Day 15 to 20). Additionally, under waterlogging stress, LDH and ADH activities significantly increased, reflecting the activation of anaerobic metabolic pathways, while PDC content continuously decreased, indicating that low-oxygen stress induced the accumulation of LDH and ADH but reduced ethanol fermentation. PCA revealed that the first two principal components explained 61.53% of the total variation, with PC1 (45.76%) reflecting the contrasting relationship between the activation of anaerobic metabolism (increased ADH and LDH activity) and decreased root activity under waterlogging stress, while PC2 (15.77%) primarily captured the responses of oxidative damage (increased MDA) and corresponding antioxidant defense (upregulated CAT and POD activities). Overall, S. japonica seedlings adapt to short-term waterlogging stress by regulating anaerobic respiration and antioxidant systems, but prolonged stress leads to a continued increase in H₂O₂ and a decline in antioxidant enzyme activities. This study provides experimental evidence and theoretical support for understanding the waterlogging tolerance mechanisms of S. japonica. This experiment provides important information on the adaptive mechanisms of plants under waterlogging stress. Full article

(This article belongs to the Section Forest Ecophysiology and Biology)

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30 pages, 3061 KiB

Open AccessReview

Air Pollution-Induced Neurotoxicity: The Relationship Between Air Pollution, Epigenetic Changes, and Neurological Disorders

by Sebastian Kalenik, Agnieszka Zaczek and Aleksandra Rodacka

Int. J. Mol. Sci. 2025, 26(7), 3402; https://doi.org/10.3390/ijms26073402 (registering DOI) - 5 Apr 2025

Abstract

Air pollution is a major global health threat, responsible for over 8 million deaths in 2021, including 700,000 fatalities among children under the age of five. It is currently the second leading risk factor for mortality worldwide. Key pollutants, such as particulate matter [...] Read more.

Air pollution is a major global health threat, responsible for over 8 million deaths in 2021, including 700,000 fatalities among children under the age of five. It is currently the second leading risk factor for mortality worldwide. Key pollutants, such as particulate matter (PM_2.5, PM₁₀), ozone, sulfur dioxide, nitrogen oxides, and carbon monoxide, have significant adverse effects on human health, contributing to respiratory and cardiovascular diseases, as well as neurodevelopmental and neurodegenerative disorders. Among these, particulate matter poses the most significant threat due to its highly complex mixture of organic and inorganic compounds with diverse sizes, compositions, and origins. Additionally, it can penetrate deeply into tissues and cross the blood–brain barrier, causing neurotoxicity which contributes to the development of neurodegenerative diseases. Although the link between air pollution and neurological disorders is well documented, the precise mechanisms and their sequence remain unclear. Beyond causing oxidative stress, inflammation, and excitotoxicity, studies suggest that air pollution induces epigenetic changes. These epigenetic alterations may affect the expression of genes involved in stress responses, neuroprotection, and synaptic plasticity. Understanding the relationship between neurological disorders and epigenetic changes induced by specific air pollutants could aid in the early detection and monitoring of central nervous system diseases. Full article

(This article belongs to the Special Issue Cellular and Molecular Study of Neurodevelopmental and Neurological Disorders)

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17 pages, 689 KiB

Open AccessReview

Pathomechanics of Early-Stage Lumbar Intervertebral Disc Degradation Leading to Discogenic Pain—A Narrative Review

by Thomas Hedman and Adam Rogers

Bioengineering 2025, 12(4), 389; https://doi.org/10.3390/bioengineering12040389 (registering DOI) - 5 Apr 2025

Abstract

Although the existence of highly prevalent pain, disability, and work time lost associated with discogenic low back pain is well known, the recognition of the culpability of universally present disc degradation and mechanical insufficiency in the first three decades of life is often [...] Read more.

Although the existence of highly prevalent pain, disability, and work time lost associated with discogenic low back pain is well known, the recognition of the culpability of universally present disc degradation and mechanical insufficiency in the first three decades of life is often overlooked. There is a corresponding “treatment gap” and no current interventions with demonstrated capabilities to address the pain and resist the usual progression of increasing structural failure of spinal tissues with increasing levels of pain and disability. This narrative review summarizes more than forty years of the literature describing the pathomechanics of progressive degradation of lumbar discs, with a focus on studies that implicate an increasing mechanical insufficiency in the etiology of early-stage chronic and recurrent discogenic low back pain. Topics highlighted in this review include the deleterious biological changes that begin soon after birth, stress intensification due to the loss of fluid phase load support, fatigue weakening and damage accumulation in non-regenerative tissue, disc tears, segmental instability, and the timeline for first incidence of chronic low back pain. The review concludes with preferred treatment characteristics and a brief summary of emerging treatment approaches. Full article

(This article belongs to the Section Biomechanics and Sports Medicine)

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15 pages, 35428 KiB

Open AccessArticle

Low Caffeine Concentrations Induce Callus and Direct Organogenesis in Tissue Cultures of Ornithogalum dubium

by Carloalberto Petti

Plants 2025, 14(7), 1127; https://doi.org/10.3390/plants14071127 (registering DOI) - 5 Apr 2025

Abstract

Caffeine is a nitrogenous base that naturally occurs in coffee (Cafea arabica), tea (Thea sinensis), and cocoa (Theobroma cacao). Chemically, caffeine is 1,3,5-trimethylxanthine, a purine analogue. Due to significant human consumption, caffeine effects have been widely studied. [...] Read more.

Caffeine is a nitrogenous base that naturally occurs in coffee (Cafea arabica), tea (Thea sinensis), and cocoa (Theobroma cacao). Chemically, caffeine is 1,3,5-trimethylxanthine, a purine analogue. Due to significant human consumption, caffeine effects have been widely studied. Being a natural xanthine derivative, the key degradative enzyme is xanthine oxidase, converting caffeine into 1-methyluric acid. Ecologically, caffeine is believed to act as a repellent molecule against insect feeding behavior. Caffeine’s chemical similarity to purines and plant hormones motivated this study, establishing the potential for cellular de-differentiation and re-differentiation. For this, a highly hormone-responsive plant species, Ornithogalum dubium, was used. As caffeine has been shown to induce endoreplication, the potential for new germlines in O. dubium is attractive. Using tissue culture, a range of caffeine concentrations were used (0.0125 mg/L to 2.0 mg/L) without additional hormones. A significant difference (p > 0.05) was observed for intermediate concentrations of 0.0125, 0.025, and 0.05 mg/L when compared to the control (no hormones). The highest rates of callus induction were obtained at a concentration of 0.025 mg/mL. Higher concentrations were phytotoxic (1.0 mg/L or greater). To conclude, caffeine-regenerated plants were not dissimilar to those obtained from canonical hormones. Full article

(This article belongs to the Special Issue Plant Tissue Culture V)

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17 pages, 5778 KiB

Open AccessArticle

Adsorption of CuSO₄ on Anatase TiO₂ (101) Surface: A DFT Study

by Frank Maldonado, Darwin Castillo, Silvio Aguilar, Javier Carrión and Aramis Sánchez

Inorganics 2025, 13(4), 114; https://doi.org/10.3390/inorganics13040114 (registering DOI) - 5 Apr 2025

Abstract

The rapid growth of industrial activities has increased environmental pollution, and solar-driven heterogeneous photocatalysis using TiO₂ has emerged as a promising solution. However, its wide band gap limits its efficiency, prompting research into various optimization strategies. One of these approaches is surface [...] Read more.

The rapid growth of industrial activities has increased environmental pollution, and solar-driven heterogeneous photocatalysis using TiO₂ has emerged as a promising solution. However, its wide band gap limits its efficiency, prompting research into various optimization strategies. One of these approaches is surface functionalization. Thus, this study investigates the adsorption of CuSO₄ on the anatase TiO₂ (101) surface using density functional theory calculations. The adsorption process induced a magnetic moment of 0.97 µ_B and a slight reduction in overall bandwidth. A preferential adsorption geometry pattern with an energy of −4.31 eV was identified. Charge transfer analysis revealed a net transfer from the TiO₂ surface to the CuSO₄ molecule, with increased net atomic charges for atoms involved in new chemical bond formation, indicating a chemisorption process. These electronic structure modifications are expected to influence the electronic and catalytic properties of the material. The findings provide insights into the CuSO₄ adsorption mechanism on an anatase TiO₂ (101) surface and its impact on the properties of the material, contributing to a deeper understanding of this system. Full article

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28 pages, 12172 KiB

Open AccessArticle

The Targeted Metabolomic Signatures of Phytohormones in Leaves of Mulberry (Morus alba L.) Are Crucial for Regrowth and Specifically Modulated by the Differential Stubble Lengths

by Haonan Li, Michael Ackah, Frank Kwarteng Amoako, Aaron Tettey Asare, Jianbin Li, Zhenjiang Wang, Qiang Lin, Changyu Qiu, Mengdi Zhao and Weiguo Zhao

Plants 2025, 14(7), 1126; https://doi.org/10.3390/plants14071126 (registering DOI) - 5 Apr 2025

Abstract

Vegetative propagation of mulberry (Morus alba L.) via sapling methods, due to the ability to exponentially multiply lateral buds on stem cuttings to enhance rapid shoot formation, is crucial for sericulture industries. The sprouting of mulberry using stubbles is an emerging method [...] Read more.

Vegetative propagation of mulberry (Morus alba L.) via sapling methods, due to the ability to exponentially multiply lateral buds on stem cuttings to enhance rapid shoot formation, is crucial for sericulture industries. The sprouting of mulberry using stubbles is an emerging method for rapid and mass production of mulberry leaves, but the growth mechanisms associated with its use remain obscure. This study is the first to report how the differential stubble lengths from mulberry plants alter and modulate phytohormones and the associated mechanisms. This study seeks to evaluate the growth mechanisms by elucidating the phytohormone signature modulation in response to differential stubble lengths of 0 cm, 5 cm, 10 cm, 20 cm, and a control via targeted metabolomics analysis in mulberry leaves. The results consistently show that the use of differential stubble lengths of mulberry promoted growth, the number of buds, aboveground biomass, and branch and leaf weights by improving the net photosynthesis, transpiration rate, stomatal conductance, and intercellular CO₂ relative to the control. The differential stubble lengths not only caused contrasting responses in the contents of plant hormones, including salicylic acid (SA), abscisic acid (ABA), indole-3-acetic acid (IAA), jasmonic acid (JA), and gibberellin (GA), but also modulated higher elemental contents relative to the control. The results further reveal significant and positive correlations between the phytohormones and all growth, biomass, and photosynthetic parameters, highlighting the role of phytohormones in the sprouting and rejuvenation of mulberry stubbles. Meanwhile, the targeted metabolomics analysis identified a total of 11 differentially accumulated phytohormones in response to the differential stubble lengths, which were significantly implicated and enriched in three major pathways, including the biosynthesis of plant hormones (ko01070), metabolic pathways (ko01100), and the plant hormone signal transduction pathway (ko04575). The use of stubbles for rapid leaf production in mulberry plants is of great importance to improve early sprouting and cutting survival, as well as shortening growth and rooting time, and is highly recommended for the sericulture industries. Full article

(This article belongs to the Special Issue Molecular Mechanisms of Interaction and Adaptation Between Non-Model Plants and the Environment)

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13 pages, 2594 KiB

Open AccessArticle

Harnessing Nanopore Sequencing to Investigate the Epigenomic Landscape in Molar Incisor Hypomineralization—A Pilot Study

by Silvia Salatino, Piotr Cuber, Wojciech Tynior, Carla Gustave, Dorota Hudy, Yuen-Ting Chan, Agnieszka Raczkowska-Siostrzonek, Raju Misra, Dagmara Aleksandrowicz, Dariusz Nałęcz and Joanna Katarzyna Strzelczyk

Int. J. Mol. Sci. 2025, 26(7), 3401; https://doi.org/10.3390/ijms26073401 (registering DOI) - 5 Apr 2025

Abstract

Molar incisor hypomineralization (MIH) is a dental condition that affects the enamel of permanent molars and/or incisors, often leading to tooth decay. Although several etiological hypotheses have come forward, including prenatal medical problems and postnatal illness, the pathogenesis of MIH is yet unclear. [...] Read more.

Molar incisor hypomineralization (MIH) is a dental condition that affects the enamel of permanent molars and/or incisors, often leading to tooth decay. Although several etiological hypotheses have come forward, including prenatal medical problems and postnatal illness, the pathogenesis of MIH is yet unclear. Aimed at exploring the epigenomic landscape of this dental condition, we collected dental tissue from a MIH-affected child and an age-matched control patient and investigated their DNA methylation status through an in-depth analysis of nanopore long-read sequencing data. We identified 780,141 CpGs with significantly different methylation levels between the samples; intriguingly, the density of these dinucleotides was higher in the regions containing genes involved in dental morphogenesis and inflammatory processes leading to periodontitis. Further examination of 54 genes associated with MIH or hypomineralized second primary molar disorders revealed very distinct methylation of intragenic transposable elements (SINEs, LINEs, and LTRs), while functional profiling analysis of 571 differentially methylated regions genome-wide uncovered significant enrichment processes including ameloblasts differentiation and calcium ion binding, as well as SP1 and other zinc finger transcription factors. Taken together, our findings suggest that DNA methylation could play a role in the pathogenesis of MIH and represent a stepping stone towards a comprehensive understanding of this multifactorial disorder. Full article

(This article belongs to the Special Issue Dental Health and Disease: From the Molecular and Pathological Perspectives)

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18 pages, 12782 KiB

Open AccessArticle

Seasonal Spatiotemporal Dynamics and Gradients of the Urban Heat Island Effect in Subtropical Furnace Megacity

by Chen Fu, Cong Chen and Zhitao Fu

Sustainability 2025, 17(7), 3238; https://doi.org/10.3390/su17073238 (registering DOI) - 5 Apr 2025

Abstract

Urban heat island (UHI) effect significantly influences the urban sustainability and health of cities and varies seasonally. However, spring and autumn have received less attention. Furthermore, research on long-term seasonal UHI changes and impacts is insufficient. This study examines the seasonal spatiotemporal dynamics [...] Read more.

Urban heat island (UHI) effect significantly influences the urban sustainability and health of cities and varies seasonally. However, spring and autumn have received less attention. Furthermore, research on long-term seasonal UHI changes and impacts is insufficient. This study examines the seasonal spatiotemporal dynamics and gradient characteristics of UHI in spring, summer, autumn, and winter in Changsha, a typical subtropical “furnace city” from 2006 to 2022. (1) Spatiotemporal dynamics: The high-temperature UHI (relatively high-temperature zone and high-temperature zone) range expands most significantly in spring and least in autumn. Additionally, the UHI migrates northward within the study area, and proximity to the urban core results in multiple high-temperature UHI effects. (2) Gradient characteristics: The proportion of the high-temperature UHI in spring, summer, autumn, and winter decreases to varying degrees within the 5 km gradient from the central point, but increases within the 6–8 km and 11–13 km gradients, especially in spring and autumn. Additionally, within the 8 km gradient in spring, the aggregation index (AI), contagion index (CONTAG), and largest patch index (LPI) decreased, with UHI patches more affected by these metrics in autumn. Overall, this study offers new insights into the seasonal effects and development of UHI, which are crucial for addressing climate change, promoting sustainability, and improving human well-being. Full article

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22 pages, 2830 KiB

Open AccessArticle

Multimodal Classification of Alzheimer’s Disease Using Longitudinal Data Analysis and Hypergraph Regularized Multi-Task Feature Selection

by Shuaiqun Wang, Huan Zhang and Wei Kong

Bioengineering 2025, 12(4), 388; https://doi.org/10.3390/bioengineering12040388 (registering DOI) - 5 Apr 2025

Abstract

Alzheimer’s disease, an irreversible neurodegenerative disorder, manifests through the progressive deterioration of memory and cognitive functions. While magnetic resonance imaging has become an indispensable neuroimaging modality for Alzheimer’s disease diagnosis and monitoring, current diagnostic paradigms predominantly rely on single-time-point data analysis, neglecting the [...] Read more.

Alzheimer’s disease, an irreversible neurodegenerative disorder, manifests through the progressive deterioration of memory and cognitive functions. While magnetic resonance imaging has become an indispensable neuroimaging modality for Alzheimer’s disease diagnosis and monitoring, current diagnostic paradigms predominantly rely on single-time-point data analysis, neglecting the inherent longitudinal nature of neuroimaging applications. Therefore, in this paper, we propose a multi-task feature selection algorithm for Alzheimer’s disease classification based on longitudinal imaging and hypergraphs (THM2TFS). Our methodology establishes a multi-task learning framework where feature selection at each temporal interval is treated as an individual task within each imaging modality. To address temporal dependencies, we implement group sparse regularization with two critical components: (1) a hypergraph-induced regularization term that captures high-order structural relationships among subjects through hypergraph Laplacian modeling, and (2) a fused sparse Laplacian regularization term that encodes progressive pathological changes in brain regions across time points. The selected features are subsequently integrated via multi-kernel support vector machines for final classification. We used functional magnetic resonance imaging and structural functional magnetic resonance imaging data from Alzheimer’s Disease Neuroimaging Initiative at four different time points (baseline (T1), 6th month (T2), 12th month (T3), and 24th month (T4)) to evaluate our method. The experimental results show that the accuracy rates of 96.75%, 93.45, and 83.78 for the three groups of classification tasks (AD vs. NC, MCI vs. NC and AD vs. MCI) are obtained, respectively, which indicates that the proposed method can not only capture the relevant information between longitudinal image data well, but also the classification accuracy of Alzheimer’s disease is improved, and it helps to identify the biomarkers associated with Alzheimer’s disease. Full article

(This article belongs to the Special Issue AI in OCT (Optical Coherence Tomography) Image Analysis)

23 pages, 667 KiB

Open AccessArticle

TPH-Fuzz: A Two-Phase Hybrid Fuzzing Framework for Smart Contract Vulnerability Detection

by Fanglei Shi, Jinsheng Yang and Zhaohui Guo

Electronics 2025, 14(7), 1465; https://doi.org/10.3390/electronics14071465 (registering DOI) - 5 Apr 2025

Abstract

Blockchain technology is revolutionizing various industries through decentralized architecture and secure transaction mechanisms, yet its core application—smart contracts—faces increasingly sophisticated security threats. Recognizing the critical need for enhanced protection in this emerging domain, this paper introduces TPH-Fuzz, a two-phase hybrid fuzzing framework designed [...] Read more.

Blockchain technology is revolutionizing various industries through decentralized architecture and secure transaction mechanisms, yet its core application—smart contracts—faces increasingly sophisticated security threats. Recognizing the critical need for enhanced protection in this emerging domain, this paper introduces TPH-Fuzz, a two-phase hybrid fuzzing framework designed to overcome current limitations in vulnerability detection. TPH-Fuzz combines global exploration with local vulnerability targeting. It utilizes dynamic symbolic execution for semantics-aware path analysis and employs data-dependency-based state modeling to generate effective transaction sequences. These methods improve both path exploration and vulnerability detection precision significantly. Experiments on a coverage dataset of 9309 contracts demonstrate an 85% branch coverage on complex contracts, outperforming conventional methods; meanwhile, tests on a vulnerability dataset of 1086 labeled contracts show a detection precision of 89.24% across eight vulnerability categories. The promising results underscore the framework’s potential to transform security auditing practices in the blockchain industry, paving the way for more reliable smart contract development and deployment. Full article

(This article belongs to the Section Computer Science & Engineering)

18 pages, 1094 KiB

Open AccessArticle

Breaking the Silence: Barriers to Error Disclosure Among Nurses in the Kingdom of Saudi Arabia—A Cross-Sectional Study

by Naglaa Abdelaziz Mahmoud Elseesy, Budoor Ahmad Almezraq, Duaa Amr Hafez, Ohood Felemban and Ebaa Marwan Felemban

Healthcare 2025, 13(7), 831; https://doi.org/10.3390/healthcare13070831 (registering DOI) - 5 Apr 2025

Abstract

Background: Medical errors are common, and in particular, medication errors are one of the leading causes of morbidity and mortality in healthcare. Nurses must disclose errors to build trust and ensure patient safety despite communication barriers and fear of reprisals. Truthful documentation and [...] Read more.

Background: Medical errors are common, and in particular, medication errors are one of the leading causes of morbidity and mortality in healthcare. Nurses must disclose errors to build trust and ensure patient safety despite communication barriers and fear of reprisals. Truthful documentation and better collaboration can improve patient outcomes. Aim: The aim of this study was to assess barriers to error disclosure among nurses in the Kingdom of Saudi Arabia. Methods: A descriptive cross-sectional survey was conducted in the months of June and August 2024 using a convenience sample of 255 nurses at King Fahad Hospital (KFH), Hofuf. A self-administered questionnaire that contained socio-demographic questions, as well as the Barriers to Error Disclosure Assessment (BEDA) tool, was deployed. Results: The majority of the sample were female (92.2%) and Bachelor’s degree holders (80.8%) who had 1–5 or 6–10 years of experience, representing 45.5% and 29.0% of the sample, respectively. When medical errors occur, only 18% of the nurses disclosed them to patients and their families, and 34.5% of the respondents disclosed medical errors to another team of healthcare professionals. The types of barriers to error disclosure were identified as relating to confidence and knowledge barriers, institutional barriers, psychological barriers, and financial concern barriers. The overall barrier score had an average of 63%. The barriers with the highest scores were those relating to psychological barriers (68.2%), followed by institutional barriers (66.5%) and financial concern barriers (64.5%). Conclusions: Targeted interventions are required for addressing the identified specific needs to support healthcare providers, specifically nurses. New regulations and policy changes are crucial for training programs implementation, enhancing safety culture, and tackling job-related insecurities to minimize barriers to error disclosure and ultimately provide better patient care quality. Further investigations may include a different approach, and it is recommended to provide deeper insights into nurse experiences. Full article

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20 pages, 12622 KiB

Open AccessArticle

Settlement Expansion Versus Environmental Protection: Ecosystem Services for Environmental Regulation Planning in Izmir, Turkiye

by Esra Kut Görgün and Stefano Salata

Sustainability 2025, 17(7), 3237; https://doi.org/10.3390/su17073237 (registering DOI) - 5 Apr 2025

Abstract

Land use and planning decisions, such as the designation of urban development areas, have a significant impact on ecosystem services (Ess). In urban planning, it is essential to consider the environmental values of ecosystem services when determining urban development zones. Spatial analyses play [...] Read more.

Land use and planning decisions, such as the designation of urban development areas, have a significant impact on ecosystem services (Ess). In urban planning, it is essential to consider the environmental values of ecosystem services when determining urban development zones. Spatial analyses play a crucial role in guiding decision-making processes by balancing environmental value and urban expansion. This study aims to identify areas of alignment or conflict between environmental values derived from ecosystem services and settlement expansion zones according to the Environmental Regulation Plan in the Izmir metropolitan area. The study employs the InVEST^® (Integrated Valuation of Ecosystem Services and Trade-offs) model and Geographic Information Systems (GIS) to map ecosystem services. Environmental values derived from ecosystem services, such as habitat quality, carbon storage and sequestration, and sediment delivery ratio, were analyzed. The results demonstrate a trade-off between high environmental values and settlement expansion zones. The five largest conflict areas with high environmental value are located near the coast and were converted from shrubland and forest areas. This study underscores the importance of identifying and prioritizing conservation sites with high composite environmental value. Full article

(This article belongs to the Special Issue Sustainable Land Management: Urban Planning and Land Use)

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19 pages, 953 KiB

Open AccessReview

A Review of Smart Grid Evolution and Reinforcement Learning: Applications, Challenges and Future Directions

by Na Xu, Zhuo Tang, Chenyi Si, Jinshan Bian and Chaoxu Mu

Energies 2025, 18(7), 1837; https://doi.org/10.3390/en18071837 (registering DOI) - 5 Apr 2025

Abstract

In the face of the rapid development of smart grid technologies, it is increasingly difficult for traditional power system management methods to support the increasingly complex operation of modern power grids. This study systematically reviews new challenges and research trends in the field [...] Read more.

In the face of the rapid development of smart grid technologies, it is increasingly difficult for traditional power system management methods to support the increasingly complex operation of modern power grids. This study systematically reviews new challenges and research trends in the field of smart grid optimization, focusing on key issues such as power flow optimization, load scheduling, and reactive power compensation. By analyzing the application of reinforcement learning in the smart grid, the impact of distributed new energy’s high penetration on the stability of the system is thoroughly discussed, and the advantages and disadvantages of the existing control strategies are systematically reviewed. This study compares the applicability, advantages, and limitations of different reinforcement learning algorithms in practical scenarios, and reveals core challenges such as state space complexity, learning stability, and computational efficiency. On this basis, a multi-agent cooperation optimization direction based on the two-layer reinforcement learning framework is proposed to improve the dynamic coordination ability of the power grid. This study provides a theoretical reference for smart grid optimization through multi-dimensional analysis and research, advancing the application of deep reinforcement learning technology in this field. Full article

(This article belongs to the Special Issue Advanced Machine Learning and Big Data Technologies for Smart Cities and Grids)

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11 pages, 7861 KiB

Open AccessArticle

Chattering-Free PID-Nested Nonsingular Terminal Sliding Mode Controller Design for Electrical Servo Drives

by Nguyen Minh Trieu, Nguyen Tan No, Truong Nguyen Vu and Nguyen Truong Thinh

Mathematics 2025, 13(7), 1197; https://doi.org/10.3390/math13071197 (registering DOI) - 5 Apr 2025

Abstract

In this study, a PID-nested nonsingular terminal sliding controller is proposed to minimize the chattering phenomenon. By adding both integral and derivative errors of states into the nonsingular terminal sliding manifolds, a composite sliding manifold was created. Compared to nonsingular terminal sliding mode [...] Read more.

In this study, a PID-nested nonsingular terminal sliding controller is proposed to minimize the chattering phenomenon. By adding both integral and derivative errors of states into the nonsingular terminal sliding manifolds, a composite sliding manifold was created. Compared to nonsingular terminal sliding mode (NTSM) techniques, this sliding manifold can handle higher-order derivatives. The speed of the motor is controlled by a sliding control law determined through a higher-order integral, making the signal continuous, and the sliding manifold is achieved in finite time. A special full-order terminal sliding mode manifold is introduced, which allows the system to converge in finite time while being chattering-free and avoiding the singularity phenomenon of conventional and terminal sliding modes. The controller’s efficiency is demonstrated with faster convergence time and fewer errors than state-of-the-art controllers, which is demonstrated through both simulation and experiment. Full article

(This article belongs to the Topic Intelligent Control in Smart Energy Systems)

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12 pages, 4732 KiB

Open AccessArticle

Recycling Waste Fiberglass by Powder Grinding and Direct Molding of Powders

by Fabrizio Quadrini, Leandro Iorio, Giorgio Patrizii, Denise Bellisario and Loredana Santo

Polymers 2025, 17(7), 987; https://doi.org/10.3390/polym17070987 (registering DOI) - 5 Apr 2025

Abstract

Direct molding is a compression molding process of thermoset particles without the addition of any linking agent or binder. It is suitable for recycling end-of-life fiberglass or other waste from the manufacturing of fiberglass products. In this study, for the first time, the [...] Read more.

Direct molding is a compression molding process of thermoset particles without the addition of any linking agent or binder. It is suitable for recycling end-of-life fiberglass or other waste from the manufacturing of fiberglass products. In this study, for the first time, the feasibility of recycling waste fiberglass powder, collected from an industry, is shown in the case of a vinyl ester matrix. Powders have been directly molded, without any pre-treatment such as sieving, to manufacture small samples for four-point bending tests. Supplied powders have been characterized by microscopy and thermal analysis. Its size distribution has been evaluated by sieving, and the amount of resin by burning test. Samples have been compression molded in an eight-cavity mold and have shown good homogeneity and surface aspect. The average density of the recycled fiberglass is 1.23 g/cm³, the bending strength 28 MPa, the elongation at break 1.6%, and the elastic modulus 1.9 GPa, with low dispersion (7% at maximum). Surface analysis has shown a rough surface and the presence of embedded glass fibers into the agglomerated fiberglass. Results show that waste powders from secondary processes of fiberglass manufacturers, such as surface grinding, may provide secondary raw materials for the production of molded parts without mixing with virgin substances. Full article

(This article belongs to the Section Circular and Green Sustainable Polymer Science)

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