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Keywords = orbital volume analysis

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23 pages, 4099 KB  
Article
Hydrothermal Modification of Activated Carbon Enhances Acetaminophen Adsorption: Experimental and Computational Evidence of π–π Interaction Dominance
by Astrid G. Cortés-Cruz, Marta Adame-Pereira, Carlos J. Durán-Valle and Ignacio M. López-Coca
Molecules 2025, 30(21), 4295; https://doi.org/10.3390/molecules30214295 - 5 Nov 2025
Viewed by 168
Abstract
Acetaminophen (APAP) is a widely used pharmaceutical increasingly detected as a contaminant in aquatic environments due to its persistent nature and incomplete removal by conventional wastewater treatment. This study investigates the adsorption performance and mechanisms of commercial activated carbon (M) and its hydrothermally [...] Read more.
Acetaminophen (APAP) is a widely used pharmaceutical increasingly detected as a contaminant in aquatic environments due to its persistent nature and incomplete removal by conventional wastewater treatment. This study investigates the adsorption performance and mechanisms of commercial activated carbon (M) and its hydrothermally modified form (MH) for APAP removal. Characterization via elemental analysis, X-ray photoelectron spectroscopy (XPS), and N2 adsorption isotherms revealed that hydrothermal treatment reduced oxygen content and enhanced micro- and mesopore volumes, resulting in a more homogeneous and carbon-rich surface. Batch adsorption experiments conducted under varying pH (5–7) and temperature (30–40 °C) conditions showed that MH achieved up to 94.3% APAP removal, outperforming the untreated carbon by more than 15%. Kinetic modeling indicated that adsorption followed a pseudo-second-order mechanism (R2 > 0.99), and isotherm data fitted best to the Langmuir model for MH and the Freundlich model for M, reflecting their differing surface properties. Adsorption was enhanced at lower pH and higher temperatures, consistent with an endothermic and pH-dependent mechanism. Complementary density functional theory (DFT) simulations confirmed that π–π stacking is the dominant interaction between APAP and the carbon surface. The most favorable configuration involved coplanar stacking with non-oxidized graphene (ΔG = −33 kJ/mol), while oxidized graphene models exhibited weaker interactions. Natural Bond Orbital (NBO) analysis further supported the prevalence of π–π interactions over dipole interactions. These findings suggest that surface deoxygenation and improved pore architecture achieved via hydrothermal treatment significantly enhance APAP adsorption, offering a scalable strategy for pharmaceutical pollutant removal in water treatment applications. Full article
(This article belongs to the Special Issue New Insights into Porous Materials in Adsorption and Catalysis)
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13 pages, 4377 KB  
Article
A Reproducible 3D Classification of Orbital Morphology Derived from CBCT and FBCT Segmentation
by Natalia Bielecka-Kowalska, Bartosz Bielecki-Kowalski and Marcin Kozakiewicz
J. Clin. Med. 2025, 14(21), 7836; https://doi.org/10.3390/jcm14217836 - 4 Nov 2025
Viewed by 132
Abstract
Background: Accurate reconstruction of the orbit after trauma or oncological resection requires reliable anatomical references. In unilateral cases, the contralateral orbit can guide repair, but bilateral injuries or pathologies remove this option. To address this problem, we developed a new morphological classification [...] Read more.
Background: Accurate reconstruction of the orbit after trauma or oncological resection requires reliable anatomical references. In unilateral cases, the contralateral orbit can guide repair, but bilateral injuries or pathologies remove this option. To address this problem, we developed a new morphological classification of orbits based on three linear dimensions. Methods: A total of 499 orbits from patients of Caucasian descent (age 8–88 years) were analyzed using three-dimensional models generated from cone-beam and fan-beam CT scans. Orbital depth (D), height (H), and width (W) were measured, and proportional indices were calculated. K-means clustering (k = 3) identified recurring morphotypes, validated by linear discriminant analysis (LDA) and supported by ANOVA, Kruskal–Wallis, and correlation tests (age and sex). Results: Three morphotypes were identified: Tall & Broad (type A, 33.5%), Deep & Broad (type B, 30.2%), and Compact (type C, 36.2%). All dimensions differed significantly between groups (ANOVA, p < 1 × 10−16; η2 = 0.40–0.51). Male orbits were significantly deeper and wider than female ones (p < 0.001). LDA demonstrated excellent separation with 97.5% accuracy. A simplified decision algorithm achieved 82.1% classification accuracy. In situations where only orbital depth could be measured, an alternative cut-off-based method reached 61.5% accuracy, with type B and C better distinguished than type A. Conclusions: The proposed classification provides a reproducible framework for describing orbital morphology. It may serve as a reference in cases where local anatomy is disrupted or the contralateral orbit is unavailable. Even millimeter-scale differences in orbital dimensions may correspond to clinically relevant changes in orbital volume and globe position, underlining the potential usefulness of this system in surgical planning. Full article
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28 pages, 587 KB  
Article
The Lyra–Schwarzschild Spacetime
by M. C. Bertin, R. R. Cuzinatto, J. A. Paquiyauri and B. M. Pimentel
Universe 2025, 11(9), 315; https://doi.org/10.3390/universe11090315 - 12 Sep 2025
Viewed by 591
Abstract
In this paper, we provide a complete analysis of the most general spherical solution of the Lyra scalar-tensor (LyST) gravitational theory based on the proper definition of a Lyra manifold. Lyra’s geometry features the metric tensor and a scale function as fundamental fields, [...] Read more.
In this paper, we provide a complete analysis of the most general spherical solution of the Lyra scalar-tensor (LyST) gravitational theory based on the proper definition of a Lyra manifold. Lyra’s geometry features the metric tensor and a scale function as fundamental fields, resulting in generalizations of geometrical quantities such as the affine connection, curvature, torsion, and non-metricity. A proper action is defined considering the correct invariant volume element and the scalar curvature, obeying the symmetry of Lyra’s reference frame transformations and resulting in a generalization of the Einstein–Hilbert action. The LyST gravity assumes zero torsion in a four-dimensional metric-compatible spacetime. In this work, geometrical quantities are presented and solved via Cartan’s technique for a spherically symmetric line element. Birkhoff’s theorem is demonstrated so that the solution is proven to be static, resulting in the Lyra–Schwarzschild metric, which depends on both the geometrical mass (through a modified version of the Schwarzschild radius rS) and an integration constant dubbed the Lyra radius rL. We study particle and light motion in Lyra–Schwarzschild spacetime using the Hamilton–Jacobi method. The motion of massive particles includes the determination of the rISCO and the periastron shift. The study of massless particle motion shows the last photon’s unstable orbit. Gravitational redshift in Lyra–Schwarzschild spacetime is also reviewed. We find a coordinate transformation that casts Lyra–Schwarzschild spacetime in the form of the standard Schwarzschild metric; the physical consequences of this fact are discussed. Full article
(This article belongs to the Section Gravitation)
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10 pages, 3502 KB  
Case Report
Volumetric Analysis of Navigation-Guided Orbital Decompression in Graves’ Orbitopathy: A Case Report
by Gonzalo Ruiz-de-Leon, Santiago Ochandiano, Sara Alvarez-Mokthari, Marta Benito-Anguita, Ismael Nieva-Pascual, Pilar Cifuentes-Canorea, Guillermo Sanjuan-de-Moreta, Jose-Ignacio Salmeron, Ignacio Navarro-Cuellar, Carlos Navarro-Cuellar and Manuel Tousidonis
Life 2025, 15(8), 1277; https://doi.org/10.3390/life15081277 - 12 Aug 2025
Viewed by 864
Abstract
Graves’ orbitopathy (GO) is a debilitating autoimmune disorder that may require surgical orbital decompression in severe cases with risk of proptosis and optic neuropathy. This report presents a case treated with navigation-assisted three-wall orbital decompression, planned with preoperative imaging and assessed using postoperative [...] Read more.
Graves’ orbitopathy (GO) is a debilitating autoimmune disorder that may require surgical orbital decompression in severe cases with risk of proptosis and optic neuropathy. This report presents a case treated with navigation-assisted three-wall orbital decompression, planned with preoperative imaging and assessed using postoperative analysis. Intraoperative navigation enabled precise localization of critical structures, improving osteotomy execution. Postoperatively, orbital volume increased by 3.5 cm3 (right eye) and 4.0 cm3 (left eye), while proptosis was reduced by 6 mm in both eyes. These changes correlated with intraocular pressure normalization and functional improvement. This was further supported by a postoperative Clinical Activity Score (CAS) of 0, indicating active orbital inflammation. Image-guided surgery (IGS) achieved an average proptosis reduction of 3.8 mm, slightly superior to that of non-guided techniques. Although IGS enhances precision and functional outcomes, it requires longer surgical time and incurs higher costs, highlighting the need for prospective studies on long-term efficacy This case supports the importance of integrating advanced imaging and navigation-assisted techniques in GO management to improve both functional and aesthetic outcomes. Full article
(This article belongs to the Special Issue 3D Imaging and Facial Reconstruction)
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11 pages, 2015 KB  
Article
Risk Factors for Radiation-Induced Keratoconjunctivitis Sicca in Dogs Treated with Hypofractionated Intensity-Modulated Radiation Therapy for Intranasal Tumors
by Akihiro Ohnishi, Soichirou Takeda, Yoshiki Okada, Manami Tokoro, Saki Kageyama, Yoshiki Itoh and Taketoshi Asanuma
Animals 2025, 15(15), 2258; https://doi.org/10.3390/ani15152258 - 1 Aug 2025
Viewed by 703
Abstract
Radiation-induced keratoconjunctivitis sicca (KCS) is a significant late complication in dogs receiving radiation therapy for intranasal tumors, particularly with hypofractionated intensity-modulated radiation therapy (IMRT). This retrospective case-control study was performed to identify anatomical and dosimetric risk factors for KCS in 15 canine patients [...] Read more.
Radiation-induced keratoconjunctivitis sicca (KCS) is a significant late complication in dogs receiving radiation therapy for intranasal tumors, particularly with hypofractionated intensity-modulated radiation therapy (IMRT). This retrospective case-control study was performed to identify anatomical and dosimetric risk factors for KCS in 15 canine patients treated with IMRT delivered in 4–6 weekly fractions of 8 Gy. Orbital structures were retrospectively contoured, and dose–volume metrics (D50) were calculated. Receiver operating characteristic (ROC) curve analysis and odds ratios were used to evaluate the associations between radiation dose and KCS development. Six dogs (33%) developed KCS within three months post-treatment. Statistically significant dose differences were observed between affected and unaffected eyes for the eyeball, cornea, and retina. ROC analyses identified dose thresholds predictive of KCS: 13.8 Gy (eyeball), 14.9 Gy (cornea), and 17.0 Gy (retina), with the retina showing the highest odds ratio (28.33). To ensure clinical relevance, KCS was diagnosed based on decreased tear production combined with corneal damage to ensure clinical relevance. This study proposes dose thresholds for ocular structures that may guide treatment planning and reduce the risk of KCS in canine patients undergoing IMRT. Further prospective studies are warranted to validate these thresholds and explore mitigation strategies for high-risk cases. Full article
(This article belongs to the Special Issue Imaging Techniques and Radiation Therapy in Veterinary Medicine)
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28 pages, 7048 KB  
Article
Enhanced Conjunction Assessment in LEO: A Hybrid Monte Carlo and Spline-Based Method Using TLE Data
by Shafeeq Koheal Tealib, Ahmed Magdy Abdelaziz, Igor E. Molotov, Xu Yang, Jian Sun and Jing Liu
Aerospace 2025, 12(8), 674; https://doi.org/10.3390/aerospace12080674 - 28 Jul 2025
Viewed by 640
Abstract
The growing density of space objects in low Earth orbit (LEO), driven by the deployment of large satellite constellations, has elevated the risk of orbital collisions and the need for high-precision conjunction analysis. Traditional methods based on Two-Line Element (TLE) data suffer from [...] Read more.
The growing density of space objects in low Earth orbit (LEO), driven by the deployment of large satellite constellations, has elevated the risk of orbital collisions and the need for high-precision conjunction analysis. Traditional methods based on Two-Line Element (TLE) data suffer from limited accuracy and insufficient uncertainty modeling. This study proposes a hybrid collision assessment framework that combines Monte Carlo simulation, spline-based refinement of the time of closest approach (TCA), and a multi-stage deterministic refinement process. The methodology begins with probabilistic sampling of TLE uncertainties, followed by a coarse search for TCA using the SGP4 propagator. A cubic spline interpolation then enhances temporal resolution, and a hierarchical multi-stage refinement computes the final TCA and minimum distance with sub-second and sub-kilometer accuracy. The framework was validated using real-world TLE data from over 2600 debris objects and active satellites. Results demonstrated a reduction in average TCA error to 0.081 s and distance estimation error to 0.688 km. The approach is computationally efficient, with average processing times below one minute per conjunction event using standard hardware. Its compatibility with operational space situational awareness (SSA) systems and scalability for high-volume screening make it suitable for integration into real-time space traffic management workflows. Full article
(This article belongs to the Section Astronautics & Space Science)
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14 pages, 696 KB  
Article
Perception of Quality of Life, Brain Regions, and Cognitive Performance in Hispanic Adults: A Canonical Correlation Approach
by Juan C. Lopez-Alvarenga, Jesus D. Melgarejo, Jesus Rivera-Sanchez, Lorena Velazquez-Alvarez, Isabel Omaña-Guzmán, Carlos Curtis-Lopez, Rosa V. Pirela, Luis J. Mena, John Blangero, Jose E. Cavazos, Michael C. Mahaney, Joseph D. Terwilliger, Joseph H. Lee and Gladys E. Maestre
Clin. Transl. Neurosci. 2025, 9(3), 33; https://doi.org/10.3390/ctn9030033 - 23 Jul 2025
Viewed by 683
Abstract
The quality of life (QoL) perception has been studied in neurological diseases; however, there is limited information linking brain morphological characteristics, QoL, and cognition. Human behavior and perception are associated with specific brain areas that interact through diffuse electrochemical networking. We used magnetic [...] Read more.
The quality of life (QoL) perception has been studied in neurological diseases; however, there is limited information linking brain morphological characteristics, QoL, and cognition. Human behavior and perception are associated with specific brain areas that interact through diffuse electrochemical networking. We used magnetic resonance imaging (MRI) to analyze the brain region volume (BRV) correlation with the scores of Rand’s 36-item Short Form Survey (SF-36) and cognitive domains (memory and dementia status). We analyzed data from 420 adult participants in the Maracaibo Aging Study (MAS). Principal component analysis with oblimin axis rotation was used to gather redundant information from brain parcels and SF-36 domains. Canonical correlation was used to analyze the relationships between SF-36 domains and BRV (adjusted for intracranial cavity), as well as sex, age, education, obesity, and hypertension. The average age (±SD) of subjects was 56 ± 11.5 years; 71% were female; 39% were obese; 12% had diabetes, 52% hypertension, and 7% dementia. No sex-related differences were found in memory and orientation scores, but women had lower QoL scores. The 1st and 2nd canonical correlation roots support the association of SF-36 domains (except social functioning and role emotional) and total brain volume, frontal lobe volume, frontal pole, lateral orbital lobe, cerebellar, and entorhinal areas. Other variables, including age, dementia, memory score, and systolic blood pressure, had a significant influence. The results of this study demonstrate significant correlations between BRV and SF-36 components, adjusted for covariates. The frontal lobe and insula were associated with the mental health component; the lateral-orbital frontal lobe and entorhinal area were correlated with the physical component. Full article
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21 pages, 4865 KB  
Article
Therapeutic Potential of Umbilical Cord MSC-Derived Exosomes in a Severe Dry Eye Rat Model: Enhancing Corneal Protection and Modulating Inflammation
by Sze-Min Chan, Chris Tsai, Tai-Ping Lee, Zih-Rou Huang, Wei-Hsiang Huang and Chung-Tien Lin
Biomedicines 2025, 13(5), 1174; https://doi.org/10.3390/biomedicines13051174 - 11 May 2025
Cited by 2 | Viewed by 2333
Abstract
Background/Objectives: Dry eye disease (DED) is a multifactorial inflammatory disease that disrupts the ocular surface, causing tear film instability, epithelial damage, and chronic inflammation. Mesenchymal stem cell-derived exosomes (MSC-exos) are promising therapeutics with immunomodulatory and regenerative properties. This study investigates the therapeutic [...] Read more.
Background/Objectives: Dry eye disease (DED) is a multifactorial inflammatory disease that disrupts the ocular surface, causing tear film instability, epithelial damage, and chronic inflammation. Mesenchymal stem cell-derived exosomes (MSC-exos) are promising therapeutics with immunomodulatory and regenerative properties. This study investigates the therapeutic effects of umbilical cord MSC-derived exosomes (UCMSC-exos) in a severe dry eye model, induced by a surgical resection of the infra-orbital (ILG) and extra-orbital lacrimal gland (ELG) in rats. Methods: Clinical evaluations, including tear volume measurement, slit lamp biomicroscopy, fluorescein staining, and spectral domain optical coherence tomography (SD-OCT), were performed to assess corneal neovascularization, corneal abrasion, and epithelial/stromal thickness. Histopathological analysis, immunohistochemistry, and mRNA gene expression were conducted to evaluate corneal tissue changes and inflammatory marker expression. Results: The results show that the treatment group exhibited significantly reduced corneal neovascularization compared to the control group (p = 0.030). During the first month, the Exo group also had a significantly lower corneal fluorescein staining area (p = 0.032), suggesting accelerated wound healing. SD-OCT analysis revealed that the corneal epithelial thickness in the treatment group was closer to normal levels compared to the control group (p = 0.02 and p = 0.006, respectively). UCMSC-exos treatment also modulated the expression of α-SMA and apoptosis in the cornea. Additionally, the gene expression of inflammatory cytokines (IL-1β and TNF-α) were downregulated. Conclusions: These findings suggest that MSC-exosome therapy offers a novel, cell-free regenerative approach for managing severe DED, modulating inflammatory response. Full article
(This article belongs to the Section Cell Biology and Pathology)
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15 pages, 10805 KB  
Article
DFT-Based Investigation of Pd-Modified WO3/Porous Silicon Composites for NO2 Gas Sensors: Enhanced Synergistic Effect and High-Performance Sensing
by Xiaoyong Qiang, Zhipeng Wang, Yongliang Guo and Weibin Zhou
Coatings 2025, 15(5), 570; https://doi.org/10.3390/coatings15050570 - 9 May 2025
Viewed by 738
Abstract
Pd-WO3 coatings on porous silicon (PSi) substrates are engineered to enhance interfacial charge transfer and surface reactivity through atomic-scale structural tailoring. This study combines first-principles calculations and experimental characterization to elucidate how Pd nanoparticles (NPs) optimize the coating’s electronic structure and environmental [...] Read more.
Pd-WO3 coatings on porous silicon (PSi) substrates are engineered to enhance interfacial charge transfer and surface reactivity through atomic-scale structural tailoring. This study combines first-principles calculations and experimental characterization to elucidate how Pd nanoparticles (NPs) optimize the coating’s electronic structure and environmental stability. The hierarchical PSi framework with uniform nanopores (200–500 nm) serves as a robust substrate for WO3 nanorod growth (50–100 nm diameter), while Pd decoration (15%–20% surface coverage) strengthens Pd–O–W interfacial bonds, amplifying electron density at the Fermi level by 2.22-fold. Systematic computational analysis reveals that Pd-induced d-p orbital hybridization near the Fermi level (−2 to +1 eV) enhances charge delocalization, optimizing interfacial charge transfer. Experimentally, these modifications enhance the coating’s response to environmental degradation, showing less than 3% performance decay over 30 days under cyclic humidity (45 ± 3% RH). Although designed for gas sensing, the coating’s high surface-to-volume ratio and delocalized charge transport channels demonstrate broader applicability in catalytic and high-stress environments. This work provides a paradigm for designing multifunctional coatings through synergistic interface engineering. Full article
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27 pages, 7505 KB  
Article
Modular Multifunctional Composite Structure for CubeSat Applications: Embedded Battery Prototype Thermal Analysis
by Giorgio Capovilla, Enrico Cestino, Leonardo Reyneri and Federico Valpiani
Batteries 2025, 11(5), 172; https://doi.org/10.3390/batteries11050172 - 23 Apr 2025
Viewed by 932
Abstract
The present work aims to develop the current CubeSats architecture. Starting from the framework of project ARAMIS (an Italian acronym for a highly modular architecture for satellite infrastructures), a new concept of smart tiles has been developed, employing multifunctional structures and lightweight, composite [...] Read more.
The present work aims to develop the current CubeSats architecture. Starting from the framework of project ARAMIS (an Italian acronym for a highly modular architecture for satellite infrastructures), a new concept of smart tiles has been developed, employing multifunctional structures and lightweight, composite materials. This enables increased CubeSat mass efficiency and payload volume. An embedded battery tile has been designed, built, and tested from a vibration point of view. In the present work, the LiPo batteries selected for the prototype have been tested with the HPPC testing procedure, to extract their equivalent Randles circuit parameters. Thus, the thermal power dissipation from the batteries can be estimated. With these data, Thermal Desktop simulations of a representative ARAMIS CubeSat are performed, considering LEO orbit and hot/cold cases. Firstly, a parametric analysis was conducted to evaluate the thermal behaviors of various design alternatives. A suitable configuration for the CubeSat was then found, enabling the validation of the embedded battery tile from a thermal point of view. The final configuration includes heaters for the LiPo batteries, a commercial CubeSat skeleton made in aluminum alloy, and a top coating for smart tiles with proper solar absorptivity. Full article
(This article belongs to the Special Issue Rechargeable Batteries)
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15 pages, 10610 KB  
Article
Geological Hazard Risk Assessment Based on Time-Series InSAR Deformation: A Case Study of Xiaojin County, China
by Jiancun Li, Zhao Yan, Liqiang Tong, Yi Wang and Shangyuan Yu
Appl. Sci. 2025, 15(8), 4143; https://doi.org/10.3390/app15084143 - 9 Apr 2025
Cited by 1 | Viewed by 560
Abstract
Geological hazard risk assessment provides essential scientific support for geological disaster prevention and governance. The selection of appropriate evaluation factors is crucial to the accuracy and practicality of the risk assessment results. The existing factors for geological hazard risk assessment often suffer from [...] Read more.
Geological hazard risk assessment provides essential scientific support for geological disaster prevention and governance. The selection of appropriate evaluation factors is crucial to the accuracy and practicality of the risk assessment results. The existing factors for geological hazard risk assessment often suffer from issues such as poor timeliness and insufficient completeness. Interferometric Synthetic Aperture Radar (InSAR) technology, which offers large-scale, high spatiotemporal resolution monitoring of surface deformation, can effectively compensate for the shortcomings of existing risk assessment factors. How to effectively integrate time-series InSAR deformation results into geological hazard risk assessment has become a focus of research. This study fully considers the time-series InSAR deformation information; both the ascending and descending orbit results of the time-series InSAR deformation are introduced as two categories of evaluation factors in the risk assessment model. Subsequently, 11 types of assessment factors are selected by the Pearson correlation coefficient method, while the Information Volume Model and Evidence Weight Model are applied in the partitioning and assessment of risks in Xiaojin County, China. Finally, ROC (Receiver Operating Characteristic Curve) analysis is utilized to compare the accuracy of model evaluations before and after incorporating time-series InSAR deformation results. The results indicate that: (1) after incorporating time-series InSAR deformation monitoring results as evaluation factors into the information volume model and evidence weight model, the evaluation accuracy of the two models improved by 9.69% and 11.26%, respectively; (2) there are differences in risk partitioning among different evaluation models. From the risk partitioning result of Xiaojin County in this study, the evaluation accuracy of the information volume model is higher than that of the evidence weight model, and the performance is more prominent after adding the time-series InSAR deformation results. Full article
(This article belongs to the Topic Remote Sensing and Geological Disasters)
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12 pages, 3371 KB  
Article
Establishment of Lunar Soil Excavation Model and Experimental Simulation Study
by Shengyi Jin, Hongtao Cao, Xiangjin Deng, Yanhong Zheng, Long Xue and Meng Zou
Aerospace 2025, 12(4), 315; https://doi.org/10.3390/aerospace12040315 - 7 Apr 2025
Viewed by 769
Abstract
Understanding and clarifying the excavation mechanism of lunar soil, as well as the interaction between the sampling shovel and lunar soil, are crucial for improving surface sampling efficiency and ensuring equipment safety. Based on the Swick and Perumpral model, an excavation model for [...] Read more.
Understanding and clarifying the excavation mechanism of lunar soil, as well as the interaction between the sampling shovel and lunar soil, are crucial for improving surface sampling efficiency and ensuring equipment safety. Based on the Swick and Perumpral model, an excavation model for the sampling shovel during the surface sampling process was established. This study focuses on JLU-6 simulated lunar soil and conducts a total of 81 experiments to investigate the sampling depth, excavation torque, and sampling volume under different sampling conditions, such as excavation angles and soil compaction levels. In addition, discrete element simulations of the surface sampling excavation process were conducted. The results indicated that the mass of soil excavated by the sampling shovel increased with the sampling angle, while the sampling increment decreased as the angle increased. The sampling resistance also increased with the sampling angle, with most of the additional resistance being used to shear and break the soil layers, rather than being fully converted into an increase in the sampling volume. At the same time, the established excavation model was analyzed through both experiments and simulations. The analysis results show that the model can predict the excavation resistance based on the excavation angle and depth, providing a reference for in-orbit operations. Full article
(This article belongs to the Section Astronautics & Space Science)
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52 pages, 15198 KB  
Article
Differences in Anatomical Structures and Resting-State Brain Networks Between Elite Wrestlers and Handball Athletes
by Fatma Sahin Ozarslan and Adil Deniz Duru
Brain Sci. 2025, 15(3), 285; https://doi.org/10.3390/brainsci15030285 - 7 Mar 2025
Cited by 1 | Viewed by 1605
Abstract
Background/Objectives: Advancements in biomedical imaging technologies over the past few decades have made it increasingly possible to measure the long-term effects of exercise on the central nervous system. This study aims to compare the brain morphology and functional connectivity of wrestlers and handball [...] Read more.
Background/Objectives: Advancements in biomedical imaging technologies over the past few decades have made it increasingly possible to measure the long-term effects of exercise on the central nervous system. This study aims to compare the brain morphology and functional connectivity of wrestlers and handball players, exploring sport-specific neural adaptations. Methods: Here, we examined 26 elite male athletes (13 wrestlers and 13 handball players) using anatomical and resting-state functional magnetic resonance imaging (fMRI) measurements. Connectivity maps are derived using the seed-based correlation analysis of resting-state fMRI, while voxel-based morphometry (VBM) is employed to identify anatomical differences. Additionally, the cortical thickness and global volumetric values of the segmented images are examined to determine the distinctions between elite wrestlers and handball players using non-parametric statistical tests. Results: Wrestlers exhibited greater grey matter volume (GMV) in the right middle temporal gyrus, left middle frontal gyrus, and right posterior cingulate gyrus (uncorr., p < 0.001). On the other hand, wrestlers showed increased functional connectivity in the left superior temporal gyrus, left parahippocampal gyrus, the left anterior orbital gyrus, and right superior frontal gyrus–medial frontal region (P(FWE) < 0.05). In addition, wrestlers showed greater cortical thickness in several brain regions. Conclusions: The increased GMV, cortical thickness, and functional connectivity observed in wrestlers highlight the presence of sport-specific neural adaptations. While this research provides valuable insights into the neuroplastic effects of various athletic disciplines, further studies involving additional sports and control groups are needed for a more comprehensive understanding. Full article
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15 pages, 1780 KB  
Article
Relaxation Modeling of Unidirectional Carbon Fiber Reinforced Polymer Composites Before and After UV-C Exposure
by Flavia Palmeri and Susanna Laurenzi
Fibers 2024, 12(12), 110; https://doi.org/10.3390/fib12120110 - 11 Dec 2024
Cited by 2 | Viewed by 1909
Abstract
Carbon fiber-reinforced polymers (CFRPs) are widely used in aerospace for their lightweight and high-performance characteristics. This study examines the long-term viscoelastic behavior of CFRP after UV-C exposure, simulating low Earth orbit conditions. The viscoelastic properties of the polymer were evaluated using dynamic mechanical [...] Read more.
Carbon fiber-reinforced polymers (CFRPs) are widely used in aerospace for their lightweight and high-performance characteristics. This study examines the long-term viscoelastic behavior of CFRP after UV-C exposure, simulating low Earth orbit conditions. The viscoelastic properties of the polymer were evaluated using dynamic mechanical analysis and the time-temperature superposition principle on both unexposed and UV-C-exposed samples. After UV-C exposure, the polymer’s instantaneous modulus decreased by about 15%. Over a 32-year period, the modulus of the unexposed resin is expected to degrade to approximately 25% of its initial value, while the exposed resin drops to around 15%. These experimental results were incorporated into finite element method models of a unidirectional CFRP representative volume element. The simulations showed that UV-C exposure caused only a slight reduction in the CFRP’s axial relaxation coefficient along the fiber’s axis, with no significant time-dependent degradation, as the fiber dominates this behavior. In contrast, the axial relaxation coefficient perpendicular to the fiber’s axis, as well as the off-diagonal and shear relaxation coefficients, showed more notable changes, with an approximate 10% reduction in their initial values after UV-C exposure. Over 32 years, degradation became much more severe, with differences between the pre- and post-exposure coefficient values reaching up to nearly 60%. Full article
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17 pages, 1272 KB  
Article
Segmentation-Based Measurement of Orbital Structures: Achievements in Eyeball Volume Estimation and Barriers in Optic Nerve Analysis
by Yong Oh Lee, Hana Kim, Yeong Woong Chung, Won-Kyung Cho, Jungyul Park and Ji-Sun Paik
Diagnostics 2024, 14(23), 2643; https://doi.org/10.3390/diagnostics14232643 - 23 Nov 2024
Viewed by 1184
Abstract
Background/Objective: Orbital diseases often require precise measurements of eyeball volume, optic nerve sheath diameter (ONSD), and apex-to-eyeball distance (AED) for accurate diagnosis and treatment planning. This study aims to automate and optimize these measurements using advanced deep learning segmentation techniques on orbital Computed [...] Read more.
Background/Objective: Orbital diseases often require precise measurements of eyeball volume, optic nerve sheath diameter (ONSD), and apex-to-eyeball distance (AED) for accurate diagnosis and treatment planning. This study aims to automate and optimize these measurements using advanced deep learning segmentation techniques on orbital Computed Tomography (CT) scans. Methods: Orbital CT datasets from individuals of various age groups and genders were used, with annotated masks for the eyeball and optic nerve. A 2D attention U-Net architecture was employed for segmentation, enhanced with slice-level information embeddings to improve contextual understanding. After segmentation, the relevant metrics were calculated from the segmented structures and evaluated for clinical applicability. Results: The segmentation model demonstrated varying performance across orbital structures, achieving a Dice score of 0.8466 for the eyeball and 0.6387 for the optic nerve. Consequently, eyeball-related metrics, such as eyeball volume, exhibited high accuracy, with a root mean square error (RMSE) of 1.28–1.90 cm3 and a mean absolute percentage error (MAPE) of 12–21% across different genders and age groups. In contrast, the lower accuracy of optic nerve segmentation led to less reliable measurements of optic nerve sheath diameter (ONSD) and apex-to-eyeball distance (AED). Additionally, the study analyzed the automatically calculated measurements from various perspectives, revealing key insights and areas for improvement. Conclusions: Despite these challenges, the study highlights the potential of deep learning-based segmentation to automate the assessment of ocular structures, particularly in measuring eyeball volume, while leaving room for further improvement in optic nerve analysis. Full article
(This article belongs to the Special Issue Deep Learning in Medical Image Segmentation and Diagnosis)
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