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20 pages, 768 KiB

Open AccessArticle

Image-Based POI Identification for Mobile Museum Guides: Design, Implementation, and User Evaluation

by Bashar Egbariya, Rotem Dror, Tsvi Kuflik and Ilan Shimshoni

Heritage 2025, 8(7), 266; https://doi.org/10.3390/heritage8070266 (registering DOI) - 6 Jul 2025

Abstract

Indoor positioning remains a significant challenge, particularly in environments such as Full article

21 pages, 6314 KiB

Open AccessArticle

Metagenomic and Metabolomic Perspectives on the Drought Tolerance of Broomcorn Millet (Panicum miliaceum L.)

by Yuhan Liu, Jiangling Ren, Binhong Yu, Sichen Liu and Xiaoning Cao

Microorganisms 2025, 13(7), 1593; https://doi.org/10.3390/microorganisms13071593 (registering DOI) - 6 Jul 2025

Abstract

Drought stress is an important abiotic stress factor restricting crop production. Broomcorn millet (Panicum miliaceum L.) has become an ideal material for analyzing the stress adaptation mechanisms of crops due to its strong stress resistance. However, the functional characteristics of its rhizosphere [...] Read more.

Drought stress is an important abiotic stress factor restricting crop production. Broomcorn millet (Panicum miliaceum L.) has become an ideal material for analyzing the stress adaptation mechanisms of crops due to its strong stress resistance. However, the functional characteristics of its rhizosphere microorganisms in response to drought remain unclear. In this study, metagenomics and metabolomics techniques were employed to systematically analyze the compositional characteristics of the microbial community, functional properties, and changes in metabolites in the rhizosphere soil of broomcorn millet under drought stress. On this basis, an analysis was conducted in combination with the differences in functional pathways. The results showed that the drought treatment during the flowering stage significantly altered the species composition of the rhizosphere microorganisms of broomcorn millet. Among them, the relative abundances of beneficial microorganisms such as Nitrosospira, Coniochaeta, Diversispora, Gigaspora, Glomus, and Rhizophagus increased significantly. Drought stress significantly affects the metabolic pathways of rhizosphere microorganisms. The relative abundances of genes associated with prokaryotes, glycolysis/gluconeogenesis, and other metabolic process (e.g., ribosome biosynthesis, amino sugar and nucleotide sugar metabolism, and fructose and mannose metabolism) increased significantly. Additionally, the expression levels of functional genes involved in the phosphorus cycle were markedly upregulated. Drought stress also significantly alters the content of specific rhizosphere soil metabolites (e.g., trehalose, proline). Under drought conditions, broomcorn millet may stabilize the rhizosphere microbial community by inducing its restructuring and recruiting beneficial fungal groups. These community-level changes can enhance element cycling efficiency, optimize symbiotic interactions between broomcorn millet and rhizosphere microorganisms, and ultimately improve the crop’s drought adaptability. Furthermore, the soil metabolome (e.g., trehalose and proline) functions as a pivotal interfacial mediator, orchestrating the interaction network between broomcorn millet and rhizosphere microorganisms, thereby enhancing plant stress tolerance. This study sheds new light on the functional traits of rhizosphere microbiota under drought stress and their mechanistic interactions with host plants. Full article

(This article belongs to the Section Microbiomes)

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23 pages, 1290 KiB

Open AccessArticle

A KeyBERT-Enhanced Pipeline for Electronic Information Curriculum Knowledge Graphs: Design, Evaluation, and Ontology Alignment

by Guanghe Zhuang and Xiang Lu

Information 2025, 16(7), 580; https://doi.org/10.3390/info16070580 (registering DOI) - 6 Jul 2025

Abstract

This paper proposes a KeyBERT-based method for constructing a knowledge graph of the electronic information curriculum system, aiming to enhance the structured representation and relational analysis of educational content. Electronic Information Engineering curricula encompass diverse and rapidly evolving topics; however, existing knowledge graphs [...] Read more.

This paper proposes a KeyBERT-based method for constructing a knowledge graph of the electronic information curriculum system, aiming to enhance the structured representation and relational analysis of educational content. Electronic Information Engineering curricula encompass diverse and rapidly evolving topics; however, existing knowledge graphs often overlook multi-word concepts and more nuanced semantic relationships. To address this gap, this paper presents a KeyBERT-enhanced method for constructing a knowledge graph of the electronic information curriculum system. Utilizing teaching plans, syllabi, and approximately 500,000 words of course materials from 17 courses, we first extracted 500 knowledge points via the Term Frequency–Inverse Document Frequency (TF-IDF) algorithm to build a baseline course–knowledge matrix and visualize the preliminary graph using Graph Convolutional Networks (GCN) and Neo4j. We then applied KeyBERT to extract about 1000 knowledge points—approximately 65% of extracted terms were multi-word phrases—and augment the graph with co-occurrence and semantic-similarity edges. Comparative experiments demonstrate a ~20% increase in non-zero matrix coverage and a ~40% boost in edge count (from 5100 to 7100), significantly enhancing graph connectivity. Moreover, we performed sensitivity analysis on extraction thresholds (co-occurrence ≥ 5, similarity ≥ 0.7), revealing that (5, 0.7) maximizes the F1-score at 0.83. Hyperparameter ablation over n-gram ranges [(1,1),(1,2),(1,3)] and top_n [5, 10, 15] identifies (1,3) + top_n = 10 as optimal (Precision = 0.86, Recall = 0.81, F1 = 0.83). Finally, GCN downstream tests show that, despite higher sparsity (KeyBERT 64% vs. TF-IDF 40%), KeyBERT features achieve Accuracy = 0.78 and F1 = 0.75, outperforming TF-IDF’s 0.66/0.69. This approach offers a novel, rigorously evaluated solution for optimizing the electronic information curriculum system and can be extended through terminology standardization or larger data integration. Full article

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21 pages, 17047 KiB

Open AccessArticle

Disturbance and Response Strategies of Carbon Sinks in Forest Land Due to Land Use Change: Taking Liushahe Town of Ningxiang as an Example

by Yu Zou, Feng Xu and Yingrui Chen

Land 2025, 14(7), 1418; https://doi.org/10.3390/land14071418 (registering DOI) - 6 Jul 2025

Abstract

Forest land plays a vital role as a terrestrial carbon sink. Urbanization, particularly the conversion of forest land into agricultural and construction areas, has significantly affected the carbon sink capacity of forests. The protection of carbon sinks in forest land has become a [...] Read more.

Forest land plays a vital role as a terrestrial carbon sink. Urbanization, particularly the conversion of forest land into agricultural and construction areas, has significantly affected the carbon sink capacity of forests. The protection of carbon sinks in forest land has become a critical issue in advancing the dual carbon strategy. Taking Liushahe Town as a case study, this study develops an integrated framework of analysis and response strategies, which encompass “land use change prediction, forest land carbon sink evaluation, and multi-objective optimization”. The purpose is to identify an optimal forest planning scheme that balances carbon sink capacity and biodiversity. The results indicate that: (1) Land use change substantially affects the extent of forest land in Liushahe Town, in which the area exhibits an initial increase followed by a decrease, and is projected to shrink to 89.88% of its 2021 level by 2041. (2) There are significant disparities in carbon sink performance among various forest land plots. The strategic elimination of inefficient plots and preservation of those with high carbon sink potential are key to enhancing the resilience of forest land to disturbances. (3) Multi-objective optimization planning schemes effectively reconcile carbon sinks and biodiversity, and enhance the synergistic effects of forest ecosystem services. Overall, this research provides practical guidance and methodological support for the protection of carbon sinks in forest land within township-scale spatial planning. Full article

(This article belongs to the Section Land Use, Impact Assessment and Sustainability)

13 pages, 841 KiB

Open AccessArticle

Silicon Protects Rice Plants Against Striped Stem Borer by Disturbing Herbivory-Induced Putrescine Accumulation

by Hao Zhang, Xiaodong Liu, Cunyan Li, Linzhi Fang, Chaoyue Gai, Rensen Zeng, Qiongli Wang, Yuanyuan Song and Daoqian Chen

Plants 2025, 14(13), 2066; https://doi.org/10.3390/plants14132066 (registering DOI) - 6 Jul 2025

Abstract

Silicon (Si) protects plants against insect herbivores; however, the underlying mechanisms remain unclear. Polyamines (PAs) play a crucial role in plant–insect interactions. Here, the involvement of Si in putrescine (Put) metabolism and its role in rice resistance against striped stem borer (SSB, Chilo [...] Read more.

Silicon (Si) protects plants against insect herbivores; however, the underlying mechanisms remain unclear. Polyamines (PAs) play a crucial role in plant–insect interactions. Here, the involvement of Si in putrescine (Put) metabolism and its role in rice resistance against striped stem borer (SSB, Chilo suppressalis Walker) were investigated. The results showed that SSB larval infestation led to a substantial accumulation of free Put in rice seedlings. Si application increased rice resistance against SSB and repressed the SSB attack-induced accumulation of Put, in parallel with a decreased expression of Put biosynthesis genes encoding arginine decarboxylase (ADC1 and ADC2). Moreover, Si application had no significant effect on the wounding-induced expression of ADC1 and ADC2, but attenuated the further elevation in the transcription of ADC1 and ADC2 induced by SSB larvae oral secretion. Simultaneously, Si addition reduced the Put and spermidine contents in SSB-attacked plants. Furthermore, the exogenous application of Put attenuated Si-enhanced resistance against SSB larvae, whereas exogenous D-arginine, an inhibitor of ADC, showed similar effects to Si on rice resistance against SSB. Our findings indicate that Si improves rice resistance to SSB, at least partly by reducing herbivory-stimulated putrescine accumulation. Full article

(This article belongs to the Special Issue Sustainable Strategies for Managing Plant Diseases)

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24 pages, 2408 KiB

Open AccessArticle

Multi-Criteria Analysis of Three Walkable Surface Configurations for Healthy Urban Trees: Suspended Grating Systems, Modular Boxes, and Structural Soils

by Magdalena Wojnowska-Heciak, Olga Balcerzak and Jakub Heciak

Sustainability 2025, 17(13), 6195; https://doi.org/10.3390/su17136195 (registering DOI) - 6 Jul 2025

Abstract

The conflicting demands of urban trees and walkable surfaces result in significant financial burdens for municipal administrators who understand that urban residents want tree-lined walkable surfaces. This study investigates three methodologies for mitigating this tension: suspended grating systems, modular box systems, and structural [...] Read more.

The conflicting demands of urban trees and walkable surfaces result in significant financial burdens for municipal administrators who understand that urban residents want tree-lined walkable surfaces. This study investigates three methodologies for mitigating this tension: suspended grating systems, modular box systems, and structural soils. A Multi-Criteria Analysis (MCA) was conducted to evaluate their suitability in dense urban areas, employing criteria categorized into Environmental, Economical, and Other considerations. The comparison focused on critical aspects such as the impact on tree health (root growth, water availability), installation complexity, initial costs, and overall suitability for diverse urban contexts. The MCA indicates that, under the given weighting of criteria, suspended grating systems (especially those suited for existing trees) rank the highest, primarily due to their superior root protection and minimal disturbance to established root systems. In contrast, modular box systems and structural soils emerge as particularly strong contenders for new tree plantings. Structural soils may have application at sites with existing trees, but the costs of removing native soil are a consideration. Sensitivity analysis suggests that modular box systems may become the preferred option when greater emphasis is placed on stormwater management and new plantings, rather than on challenges for existing trees or underground infrastructure. Structural soils score well in cost-effectiveness and installation speed but require careful implementation to address their lower root protection performance and long-term maintenance concerns. Ultimately, the optimal solution depends on unique site-specific conditions and budgetary constraints, emphasizing the necessity of tailored approaches to balance urban infrastructure with tree health. Full article

(This article belongs to the Section Sustainable Urban and Rural Development)

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13 pages, 3390 KiB

Open AccessArticle

Multiscale Modeling of Hospital Length of Stay for Successive SARS-CoV-2 Variants: A Multi-State Forecasting Framework

by Minchan Choi, Jungeun Kim, Heesung Kim, Ruarai J. Tobin and Sunmi Lee

Viruses 2025, 17(7), 953; https://doi.org/10.3390/v17070953 (registering DOI) - 6 Jul 2025

Abstract

Understanding how hospital length of stay (LoS) evolves with successive SARS-CoV-2 variants is central to the multiscale modeling and forecasting of COVID-19 and other respiratory virus dynamics. Using records from 1249 COVID-19 patients admitted to Chungbuk National University Hospital (2021–2023), we quantified LoS [...] Read more.

Understanding how hospital length of stay (LoS) evolves with successive SARS-CoV-2 variants is central to the multiscale modeling and forecasting of COVID-19 and other respiratory virus dynamics. Using records from 1249 COVID-19 patients admitted to Chungbuk National University Hospital (2021–2023), we quantified LoS across three distinct variant phases (Pre-Delta, Delta, and Omicron) and three age groups (0–39, 40–64, and 65+ years). A gamma-distributed multi-state model—capturing transitions between semi-critical and critical wards—incorporated variant phase and age as log-linear covariates. Parameters were estimated via maximum likelihood with 95% confidence intervals derived from bootstrap resampling, and Monte Carlo iterations yielded detailed LoS distributions. Omicron-phase stays were 5–8 days, shorter than the 10–14 days observed in earlier phases, reflecting improved treatment protocols and reduced virulence. Younger adults typically stayed 3–5 days, whereas older cohorts required 8–12 days, with prolonged admissions (over 30 days) clustering in the oldest group. These time-dependent transition probabilities can be integrated with real-time bed-availability alert systems, highlighting the need for variant-specific ward/ICU resource planning and underscoring the importance of targeted management for elderly patients during current and future pandemics. Full article

(This article belongs to the Special Issue Multiscale Modeling and Forecasting of COVID-19 and Respiratory Virus Dynamics)

18 pages, 3396 KiB

Open AccessArticle

Dynamic Interaction Analysis of Long-Span Bridges Under Stochastic Traffic and Wind Loads

by Ruien Wu, Yang Quan, Jia Wang, Le Li, Dingfu Ge, Siman Guo, Yaoyu Hu and Ping Xiang

Appl. Sci. 2025, 15(13), 7577; https://doi.org/10.3390/app15137577 (registering DOI) - 6 Jul 2025

Abstract

An innovative method is proposed to analyze the coupled vibration between random traffic and large-span bridges under the combined action of wind loads. The dynamic behavior of bridges subjected to these multifactorial influences is investigated through a comprehensive bridge dynamics model. Specifically, a [...] Read more.

An innovative method is proposed to analyze the coupled vibration between random traffic and large-span bridges under the combined action of wind loads. The dynamic behavior of bridges subjected to these multifactorial influences is investigated through a comprehensive bridge dynamics model. Specifically, a refined full-bridge finite element model is developed to simulate the traffic–bridge coupled vibration, with wind forces applied as external dynamic loads. The effects of wind speed and vehicle speed on the coupled system are systematically evaluated using the finite element software ABAQUS 2023. To ensure computational accuracy and efficiency, the large-span nonlinear dynamic solution method is employed, integrating the Newmark-β time integration method with the Newton–Raphson iterative technique. The proposed method is validated through experimental measurements, demonstrating its effectiveness in capturing the synergistic impacts of wind and traffic on bridge dynamics. By incorporating the stochastic nature of traffic flow and combined wind forces, this approach provides a detailed analysis of bridge responses under complex loading conditions. The study establishes a theoretical foundation and practical reference for the safety assessment of large-span bridges. Full article

(This article belongs to the Section Civil Engineering)

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13 pages, 3096 KiB

Open AccessArticle

Towards Accountability: A Primer on the Space Debris Problem and an Overview of the Legal Issues Surrounding It

by William Schonberg

Aerospace 2025, 12(7), 609; https://doi.org/10.3390/aerospace12070609 (registering DOI) - 6 Jul 2025

Abstract

Since 1957, the near-Earth population of trackable space objects has grown in number to over 36,000. Of these 36,000+ trackable objects now in low Earth orbit, just a few thousand are working spacecraft. The rest are Earth-orbiting objects which are no longer operational [...] Read more.

Since 1957, the near-Earth population of trackable space objects has grown in number to over 36,000. Of these 36,000+ trackable objects now in low Earth orbit, just a few thousand are working spacecraft. The rest are Earth-orbiting objects which are no longer operational and are considered to be space junk. Because this junk can no longer receive maneuvering commands from its Earth-based owners, the survivability of other spacecraft traveling through or operating in Earth orbit can be jeopardized by the impacts of any number of pieces of this space junk, whose origins can usually be traced back to defunct satellites. As a result, a major design parameter for Earth-orbiting spacecraft is the possibility of such high-speed impacts and the damage they can cause. Furthermore, several private companies are now launching several thousand spacecraft into Earth orbit, many of which are satellites built for communication purposes. Other satellites have been launched to expand the reach of the World Wide Web and to provide better tools for disaster management. Two questions quickly become evident, namely, what is the beneficial purpose of these large satellite constellations, and what are some of the deleterious consequences of their proliferation? Numerous topics related to space debris will be discussed in this paper, including issues in space law that concern the growing problem of orbital debris. In the end, several areas of concern will be noted that are vital to the continuing presence of humans in near-Earth space and must be addressed as the near-Earth orbital environment becomes more congested and space traffic management becomes more difficult. Full article

(This article belongs to the Special Issue Development of Novel Orbital Debris Protection Systems)

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14 pages, 2931 KiB

Open AccessArticle

Methyl Viologen@β-Zeolite with Absorption/Fluorescence Dual-Mode and Photo/Chemical Synergistic Stimuli-Responsive Chromism

by Jingxuan Han, Shaoning Li, Huihui Li, Yu Li, Jiaqiao Qin, Fuxiang Wang and Qinhe Pan

Molecules 2025, 30(13), 2872; https://doi.org/10.3390/molecules30132872 (registering DOI) - 6 Jul 2025

Abstract

In this work, methyl viologen (MV) was adsorbed into the nanopores of Si/Al H-β-zeolite via cation exchange. The resulting MV@β-zeolite possessed absorption/fluorescence dual-mode and photo/chemical synergistic stimuli-responsive chromism. Owing to the acidic surrounding provided by β-zeolite, the chromism of MV required the synergistic [...] Read more.

In this work, methyl viologen (MV) was adsorbed into the nanopores of Si/Al H-β-zeolite via cation exchange. The resulting MV@β-zeolite possessed absorption/fluorescence dual-mode and photo/chemical synergistic stimuli-responsive chromism. Owing to the acidic surrounding provided by β-zeolite, the chromism of MV required the synergistic stimuli of UV irradiation and a chemical reductant (such as Na₂SO₃). UV irradiation induced single electron transfer from the chemical reductant to MV@β-zeolite, leading to enhanced absorption at 610 nm together with a daylight color change from pale yellow to blue. Meanwhile, the nanopores of β-zeolite inhibited aggregation-caused quenching of MV, enabling MV to emit cyan fluorescence at 500 nm. After the single electron transfer of the chemical reductant under UV irradiation, the cyan fluorescence of MV@β-zeolite was quenched. Additionally, MV@β-zeolite exhibited a short stimulus response time (250 s) and good color change reversibility. These findings in this work provide valuable insights into the design of multi-mode and synergistic stimuli-responsive viologen-based chromic materials, particularly for applications in secure high-throughput information storage, high-level anti-counterfeiting and multi-target multi-mode sensing. Full article

(This article belongs to the Special Issue Novel Organic-Inorganic Hybrid Porous Photochromic Materials)

19 pages, 1908 KiB

Open AccessReview

Enhancing ELISA Sensitivity: From Surface Engineering to Synthetic Biology

by Hye-Bin Jeon, Dong-Yeon Song, Yu Jin Park and Dong-Myung Kim

Biosensors 2025, 15(7), 434; https://doi.org/10.3390/bios15070434 (registering DOI) - 6 Jul 2025

Abstract

Accurate and sensitive detection of protein biomarkers is critical for advancing in vitro diagnostics (IVD), yet conventional enzyme-linked immunosorbent assays (ELISA) often fall short in terms of sensitivity compared to nucleic acid-based tests. Bridging this sensitivity gap is essential for improving diagnostic accuracy, [...] Read more.

Accurate and sensitive detection of protein biomarkers is critical for advancing in vitro diagnostics (IVD), yet conventional enzyme-linked immunosorbent assays (ELISA) often fall short in terms of sensitivity compared to nucleic acid-based tests. Bridging this sensitivity gap is essential for improving diagnostic accuracy, particularly in diseases where protein levels better reflect disease progression than nucleic acid biomarkers. In this review, we present strategies developed to enhance the sensitivity of ELISA, structured according to the sequential steps of the assay workflow. Beginning with surface modifications, we then discuss the methodologies to improve mixing and washing efficiency, followed by a summary of recent advances in signal generation and amplification techniques. In particular, we highlight the emerging role of cell-free synthetic biology in augmenting ELISA sensitivity. Recent developments such as expression immunoassays, CRISPR-linked immunoassays (CLISA), and T7 RNA polymerase–linked immunosensing assays (TLISA) demonstrate how programmable nucleic acid and protein synthesis systems can be integrated into ELISA workflows to surpass the present sensitivity, affordability, and accessibility. By combining synthetic biology-driven amplification and signal generation mechanisms with traditional immunoassay formats, ELISA is poised to evolve into a highly modular and adaptable diagnostic platform, representing a significant step toward the next generation of highly sensitive and programmable immunoassays. Full article

(This article belongs to the Special Issue Nano Biosensors and Their Applications for In Vivo/Vitro Diagnosis—3rd Edition)

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29 pages, 345 KiB

Open AccessArticle

Spin-2 Particle in Coulomb Field: Non-Relativistic Approximation

by Alina Ivashkevich, Viktor Red’kov and Artur Ishkhanyan

Symmetry 2025, 17(7), 1075; https://doi.org/10.3390/sym17071075 (registering DOI) - 6 Jul 2025

Abstract

The primary objective of this paper is to derive a non-relativistic system of equations for a spin-2 particle in the presence of an external Coulomb field, solve these equations, and determine the corresponding energy spectra. We begin with the known radial system of [...] Read more.

The primary objective of this paper is to derive a non-relativistic system of equations for a spin-2 particle in the presence of an external Coulomb field, solve these equations, and determine the corresponding energy spectra. We begin with the known radial system of 39 equations formulated for a free spin-2 particle and modify it to incorporate the effects of the Coulomb field. By eliminating the 28 components associated with vector and rank-3 tensor fields, we reduce the system to a set of 11 second-order equations related to scalar and symmetric tensor components. In accordance with parity constraints, this system naturally groups into two subsystems consisting of three and eight equations, respectively. To perform the non-relativistic approximation, we employ the method of projective operators constructed from the matrix

Γ^{0}

of the original matrix equation. This approach allows us to derive two non-relativistic subsystems corresponding to the parity restrictions, comprising two and three coupled differential equations. Through a linear similarity transformation, we further decouple these into five independent equations with a Schrödinger-type non-relativistic structure, leading to explicit energy spectra. Special attention is given to the case of the minimal quantum number of total angular momentum,

j = 0

, which requires separate consideration. Full article

(This article belongs to the Special Issue Supersymmetry Approaches in Quantum Mechanics and Field Theory)

15 pages, 939 KiB

Open AccessArticle

Spatial Distribution and Post-COVID-19 Health Complications in Older People: A Brazilian Cohort Study

by Franciele Aline Machado de Brito, Carlos Laranjeira, Stéfane Lele Rossoni, Amira Mohammed Ali, Maria Aparecida Salci and Lígia Carreira

J. Clin. Med. 2025, 14(13), 4775; https://doi.org/10.3390/jcm14134775 (registering DOI) - 6 Jul 2025

Abstract

Background/Objectives: In the aftermath of the COVID-19 pandemic, individuals infected with SARS-CoV-2 have progressively displayed a range of symptoms linked to protracted COVID during the post-acute phase of illness. Concurrently, in several nations globally, the phenomenon of population aging has been intensifying. In [...] Read more.

Background/Objectives: In the aftermath of the COVID-19 pandemic, individuals infected with SARS-CoV-2 have progressively displayed a range of symptoms linked to protracted COVID during the post-acute phase of illness. Concurrently, in several nations globally, the phenomenon of population aging has been intensifying. In this scenario, the aged population has become both vulnerable and high-risk during the acute phase of COVID-19, and faces significant dangers associated with long-COVID. This study seeks to analyze the incidence and spatial distribution of health complications in older people affected by COVID-19, in the first year of the pandemic (2020), in the State of Paraná, as well as to identify the factors associated with the development of cardiovascular, neurological, respiratory, and metabolic diseases. Method: An observational and retrospective study was carried out in the Brazilian state of Paraná. Participants were randomly selected from two databases. A total of 893 older people (≥60 years) participated in the study 12 months after acute COVID-19 infection. Telephone questionnaires were applied between March and December 2021. The Moran index test, logistic regression, and Poisson models were used to analyze the data. Results: In terms of age, most participants (66%) were between 60 and 69 years old, 25.8% were between 70 and 79 years old, and 8.2% were 80 years old or older. Most participants were female (51.2%), white (98.1%), had a partner (69.8%), and had been hospitalized due to COVID-19 (59.3%). Cardiovascular diseases were the most frequent in the population (39.5%), followed by metabolic diseases (27.3%). The long-term use of medication was associated with the development of metabolic diseases (aOR = 9.8), cardiovascular diseases (aOR = 6.6), and diseases in multiple organic systems (aOR = 3.2); living alone was associated with neurological diseases (aOR = 2.5), and the age group of 80 years or older (aOR = 2.4) was associated with cardiovascular events. The spatial distribution showed that complications in body groups are distributed randomly among the health regions of the state, with no influence from neighboring locations. Conclusions: Post-COVID-19 health complications are more frequent in older adults who have comorbidities and long-term medication use. Therefore, long-term monitoring of these individuals and investment in public policies for rehabilitation and prevention of complications are necessary. Full article

(This article belongs to the Section Geriatric Medicine)

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11 pages, 221 KiB

Open AccessArticle

Cross-Cultural Differences in Gastrointestinal Symptoms and Sensory Responses in Individuals with Autism: A Comparison Between Spain and Colombia

by Tíscar Rodríguez-Jiménez, Ignasi Navarro-Soria and Agustín E. Martínez-González

Children 2025, 12(7), 889; https://doi.org/10.3390/children12070889 (registering DOI) - 6 Jul 2025

Abstract

Background: Between 40 and 70% of the population with autism have been found to suffer from functional gastrointestinal disorders (FGIDs). The emergence of FGIDs is related to lower quality of life and greater medical resources, somatization and emotional instability. There is a paucity [...] Read more.

Background: Between 40 and 70% of the population with autism have been found to suffer from functional gastrointestinal disorders (FGIDs). The emergence of FGIDs is related to lower quality of life and greater medical resources, somatization and emotional instability. There is a paucity of research available that examines gastrointestinal symptoms and sensory responses in individuals with autism in different countries and cultures. The aim of the present study is to compare the possible differences between gastrointestinal symptoms and sensory reactivity between two samples of individuals with autism from Spain and Colombia. Methods. Differences in gastrointestinal symptoms and sensory response were analysed between individuals with autism from Spain (n = 65; mean age = 8.91, SD = 4.02) and Colombia (n = 62; mean age = 10.16, SD = 5.31). Results. No differences were found as a function of age, sex and autism severity between Spanish and Colombian participants. More severe functional nausea and vomiting was reported by the Colombian sample when compared with the Spanish sample (p < 0.00, d = 0.42). Similarly, greater sensory reactivity emerged in Colombian individuals with autism relative to Spanish individuals with autism. Conclusions. Due to methodological limitations, sample size and other factors that could not be analysed in this research, it is not possible to draw conclusions about the influences of cultural or biological factors on gastrointestinal symptomatology and sensory reactivity among both autistic populations. This work could encourage more rigorous cross-cultural research in the future. Full article

(This article belongs to the Section Pediatric Mental Health)

26 pages, 808 KiB

Open AccessReview

A Review of Formulation Strategies for Cyclodextrin-Enhanced Solid Lipid Nanoparticles (SLNs) and Nanostructured Lipid Carriers (NLCs)

by Tarek Alloush and Burcu Demiralp

Int. J. Mol. Sci. 2025, 26(13), 6509; https://doi.org/10.3390/ijms26136509 (registering DOI) - 6 Jul 2025

Abstract

The advancement of efficient drug delivery systems continues to pose a significant problem in pharmaceutical sciences, especially for compounds with limited water solubility. Lipid-based systems, including solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs), have emerged as viable options owing to their [...] Read more.

The advancement of efficient drug delivery systems continues to pose a significant problem in pharmaceutical sciences, especially for compounds with limited water solubility. Lipid-based systems, including solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs), have emerged as viable options owing to their biocompatibility, capability to safeguard labile chemicals, and potential for prolonged release. Nonetheless, the encapsulation efficiency (EE) and release dynamics of these carriers can be enhanced by including cyclodextrins (CDs)—cyclic oligosaccharides recognized for their ability to form inclusion complexes with hydrophobic compounds. This article offers an extensive analysis of CD-modified SLNs and NLCs as multifunctional drug delivery systems. The article analyses the fundamental principles of these systems, highlighting the pre-complexation of the drug with cyclodextrins before lipid incorporation, co-encapsulation techniques, and surface adsorption after formulation. Attention is concentrated on the physicochemical interactions between cyclodextrins and lipid matrices, which influence essential factors such as particle size, encapsulation efficiency, and colloidal stability. The review includes characterization techniques, such as particle size analysis, zeta potential measurement, drug release studies, and Fourier-transform infrared spectroscopy (FT-IR)/Nuclear Magnetic Resonance (NMR) analyses. The study highlights the application of these systems across many routes of administration, including oral, topical, and mucosal, illustrating their adaptability and potential for targeted delivery. The review outlines current formulation challenges, including stability issues, drug leakage, and scalability concerns, and proposes solutions through advanced approaches, such as stimuli-responsive release mechanisms and computer modeling for system optimization. The study emphasizes the importance of regulatory aspects and outlines future directions in the development of CD-lipid hybrid nanocarriers, showcasing its potential to revolutionize the delivery of poorly soluble drugs. Full article

(This article belongs to the Special Issue Research on Cyclodextrin)

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23 pages, 3338 KiB

Open AccessArticle

European Efficiency Schemes for Domestic Gas Boilers: Estimation of Savings in Heating of Settlements

by Dejan Brkić

Algorithms 2025, 18(7), 416; https://doi.org/10.3390/a18070416 (registering DOI) - 6 Jul 2025

Abstract

This article aims to evaluate the seasonal efficiency of natural gas boilers used in European households, highlighting the cost effectiveness, environmental benefits, and user comfort associated with higher-efficiency models, particularly those based on condensing technology. The study applies a standardized algorithm used in [...] Read more.

This article aims to evaluate the seasonal efficiency of natural gas boilers used in European households, highlighting the cost effectiveness, environmental benefits, and user comfort associated with higher-efficiency models, particularly those based on condensing technology. The study applies a standardized algorithm used in European energy labeling schemes to calculate the seasonal efficiency of household gas boilers. It further includes a comparative analysis of selected boiler models available on the Serbian market and outlines a step-by-step method for estimating gas savings when replacing older, less efficient boilers with modern units. Condensing boilers demonstrate significantly higher seasonal efficiency than standard models by recovering additional heat from exhaust gases. These improved boilers produce lower greenhouse gas emissions and offer annual fuel savings of approximately 10% to 30%, depending on the boiler’s age, system design, and usage patterns. The results also confirm the direct correlation between seasonal efficiency and annual fuel consumption, validating the use of efficiency-based cost comparisons. The analysis focuses on residential gas boilers available in the Serbian market, although the models examined are commonly distributed across Europe. The findings highlight the important role of energy efficiency labels—based on a standardized algorithm—in guiding boiler selection, helping consumers and policymakers make informed decisions that promote energy savings and reduce environmental impact. This article contributes to the theoretical and practical understanding of gas boiler efficiency by integrating algorithm-based evaluation with market data and user-centered considerations. It offers actionable insights for consumers, energy advisors, and policymakers in the context of Europe’s energy transition. Verifying the efficiency calculations of gas boilers requires a careful combination of theoretical methods, measured data, and adherence to standards. Full article

(This article belongs to the Special Issue Mathematical Modelling in Engineering and Human Behaviour (3rd Edition))

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18 pages, 734 KiB

Open AccessArticle

Comparative Analysis of Pressure Platform and Insole Devices for Plantar Pressure Assessment

by Catarina M. Amaro, Maria F. Paulino, Sara Valvez, Luis Roseiro, Maria António Castro and Ana M. Amaro

Appl. Sci. 2025, 15(13), 7575; https://doi.org/10.3390/app15137575 (registering DOI) - 6 Jul 2025

Abstract

Foot plantar pressure refers to the pressure or force that the foot generates in contact with the ground, varying across different regions of the foot. This parameter is essential in static and dynamic analyses to access accurate diagnoses, study the human body biomechanics, [...] Read more.

Foot plantar pressure refers to the pressure or force that the foot generates in contact with the ground, varying across different regions of the foot. This parameter is essential in static and dynamic analyses to access accurate diagnoses, study the human body biomechanics, create functional footwear designs, aid in rehabilitation and physiotherapy, and prevent injuries in athletes during sports practice. This study presents an experimental comparison between two different plantar pressure measurement devices, Pedar^® (sensorized insoles) and Physiosensing^® (pressure platform). The devices were selected based on their capacity to measure contact area and peak pressure points. Results showed that Physiosensing^® provided a more uniform measurement of the contact area, proving its efficiency for weight distribution and stability analysis applications, particularly in posture assessment and balance studies. The Pedar^® system showed higher capacity in peak pressure point detection. Therefore, the insole system is more suitable for applications requiring precise high-pressure zone localization. Comparative analysis highlights the strengths and limitations of each device and offers insights regarding its optimal usage in clinical, sports, and research settings. Full article

(This article belongs to the Section Mechanical Engineering)

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16 pages, 792 KiB

Open AccessArticle

Measuring the Sustainability of Nitrogen Fertilization in EU Agriculture: A New Index-Based Assessment in the Context of Sustainable Intensification

by Magdalena Szymańska, Piotr Sulewski, Adam Wąs and Tomasz Sosulski

Agronomy 2025, 15(7), 1643; https://doi.org/10.3390/agronomy15071643 (registering DOI) - 6 Jul 2025

Abstract

This study comprehensively evaluated nitrogen (N) management in 27 European countries from 1990 to 2021, utilizing the FAO and LUCAS databases. The EU countries were categorized into four groups based on their agricultural production intensities: low (L), medium–low (ML), medium–high (MH), and high [...] Read more.

This study comprehensively evaluated nitrogen (N) management in 27 European countries from 1990 to 2021, utilizing the FAO and LUCAS databases. The EU countries were categorized into four groups based on their agricultural production intensities: low (L), medium–low (ML), medium–high (MH), and high (H). Additionally, a new Sustainable Nitrogen Management Indicator (SNMI) has been introduced to measure the sustainability of agricultural production. The analyses reveal significant variation in nitrogen fertilization intensity among EU countries, which correlates with differences in yield levels. Generally, higher fertilization leads to higher nutrient loss; however, the nitrogen losses per unit of yield show only minor differences between high- and low-intensity countries. From 1990 to 2021, a general improvement was observed in nitrogen management across all groups, as evidenced by a significant decline in the SNMI, indicating that agricultural production has become more sustainable. Notably, low-intensity countries showed the most significant improvement, with increased nitrogen input per hectare since the 1990s, demonstrating that moderate fertilization can enhance N use efficiency. In contrast, high-intensity countries saw decreased nitrogen inputs but still improved SNMI. These trends support the idea of sustainable intensification. The multidimensional SNMI comprehensively assesses eco-efficiency by highlighting environmental threats and production benefits. This paper demonstrates that SNMI is robust and easy to calculate using available datasets, and it can be implemented to assess nitrogen management efficiency at various scales. Full article

(This article belongs to the Special Issue Safe and Efficient Utilization of Water and Fertilizer in Crops)

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15 pages, 643 KiB

Open AccessArticle

Interactive Effect of Copper and Herbivory on the Whole-Plant Growth of Leucaena leucocephala

by Shirley Margarita Amaya-Martín, Horacio Salomón Ballina-Gómez, Esaú Ruíz-Sánchez, Gabriel Jesús Azcorra-Perera, Roberto Rafael Ruiz-Santiago and Jacques Fils Pierre

Int. J. Plant Biol. 2025, 16(3), 76; https://doi.org/10.3390/ijpb16030076 (registering DOI) - 6 Jul 2025

Abstract

This study investigated how Leucaena leucocephala, a dry forest plant, copes with soil copper and herbivory caused by Schistocerca piceifrons, crucial for understanding species adaptation in stressed environments. A 33-day factorial experiment with three copper and two herbivory treatments assessed seedling [...] Read more.

This study investigated how Leucaena leucocephala, a dry forest plant, copes with soil copper and herbivory caused by Schistocerca piceifrons, crucial for understanding species adaptation in stressed environments. A 33-day factorial experiment with three copper and two herbivory treatments assessed seedling growth rates (relative growth rate of biomass—RGR_B, and leaf area—RGR_LA), morphology, net assimilation rate (NAR), biomass allocation, and survival. Seedlings demonstrated compensatory growth in terms of RGR_B and RGR_LA under high copper and herbivory. Although copper decreased overall survival, surviving individuals effectively compensated for herbivory damage. These tolerance responses, primarily driven by an increased NAR (accounting for 98% of compensation), aligned with the limiting resource model. While most morphological components remained stable, herbivory specifically increased the root–shoot ratio. These findings indicate L. leucocephala possesses significant resilience through physiological adjustments, like enhancing NAR, and biomass reallocation strategies, allowing it to persist despite multiple stressors common in dry forests. Full article

(This article belongs to the Special Issue Plant Resistance to Insects)

19 pages, 3961 KiB

Open AccessArticle

Bernoulli Principle in Ferroelectrics

by Anna Razumnaya, Yuri Tikhonov, Dmitrii Naidenko, Ekaterina Linnik and Igor Lukyanchuk

Nanomaterials 2025, 15(13), 1049; https://doi.org/10.3390/nano15131049 (registering DOI) - 6 Jul 2025

Abstract

Ferroelectric materials, characterized by spontaneous electric polarization, exhibit remarkable parallels with fluid dynamics, where polarization flux behaves similarly to fluid flow. Understanding polarization distribution in confined geometries at the nanoscale is crucial for both fundamental physics and technological applications. Here, we show that [...] Read more.

Ferroelectric materials, characterized by spontaneous electric polarization, exhibit remarkable parallels with fluid dynamics, where polarization flux behaves similarly to fluid flow. Understanding polarization distribution in confined geometries at the nanoscale is crucial for both fundamental physics and technological applications. Here, we show that the classical Bernoulli principle, which describes the conservation of the energy flux along velocity streamlines in a moving fluid, can be extended to the conservation of polarization flux in ferroelectric nanorods with varying cross-sectional areas. Geometric constrictions lead to an increase in polarization, resembling fluid acceleration in a narrowing pipe, while expansions cause a decrease. Beyond a critical expansion, phase separation occurs, giving rise to topological polarization structures such as polarization bubbles, curls and Hopfions. This effect extends to soft ferroelectrics, including ferroelectric nematic liquid crystals, where polarization flux conservation governs the formation of complex mesoscale states. Full article

(This article belongs to the Special Issue Research on Ferroelectric and Spintronic Nanoscale Materials)

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26 pages, 635 KiB

Open AccessSystematic Review

The Impact of Physical Activity on Suicide Attempt in Children: A Systematic Review

by Marissa Patel, Grace Branjerdporn and Sabine Woerwag-Mehta

Children 2025, 12(7), 890; https://doi.org/10.3390/children12070890 (registering DOI) - 6 Jul 2025

Abstract

Suicide in children is a major global health crisis, with profound impacts on families, friends, and society. Understanding ways to ameliorate the rate of suicide attempt (SA) is critical given that it is a key factor in predicting future suicide risk. SA is [...] Read more.

Suicide in children is a major global health crisis, with profound impacts on families, friends, and society. Understanding ways to ameliorate the rate of suicide attempt (SA) is critical given that it is a key factor in predicting future suicide risk. SA is the deliberate act of causing physical injury to oneself with the intent of death. The incidence of SA may be influenced by physical activity (PA). PA includes bodily movement via skeletal muscles that results in energy expenditure and physical fitness. While there is evidence to suggest that PA improves dysregulation of the parasympathetic nervous system which underpins the physiology of suicidal behaviour, evaluating the impact of PA on SA in children is required. Objectives: This systematic review aims to determine the relationship between PA and SA in children to inform alternative preventative and interventional strategies. Methods: This systematic review was registered with PROSPERO: CRD42023389415. Eight electronic databases were systematically searched. References were transferred to Covidence software for title and abstract screening and full text review were performed based on eligibility criteria: (1) children aged 6–18 years old; (2) participated in PA (individual, group exercise, or team sports); and (3) examined SA as a dependent variable. The JBI Checklist was used to measure the quality and level of bias of included studies. Results: Of the 2322 studies identified, 21 were included in the final analysis of the review. Twenty studies were cross-sectional in design, and one implemented a prospective study design. Thirteen studies (61.9%) yielded statistically significant results, indicating that increased PA, particularly team sport, may be associated with reduced odds of SA. There was some evidence to suggest that certain intensities and frequencies of PA may be beneficial to some and detrimental to other subgroups. Conclusions: The results suggest that PA may reduce the risk of suicide attempts. Although PA may be associated with reduced SA in children, future research is required, which (1) uses standardised outcome variables; (2) adopts longitudinal and experimental study designs; (3) explores qualitative research to determine distinctive factors that influence participation in PA not captured by quantitative research; and (4) examines different target populations such as children with a broad range of mental health issues. Full article

(This article belongs to the Section Global Pediatric Health)

15 pages, 3237 KiB

Open AccessFeature PaperArticle

A Simple Fabrication of Tourmaline-Supported Ni-NiAl₂O₄ Nanocomposites for Enhanced Methane Dry Reforming Activity

by Jin Wang, Xianku Wang, Pengfei Zhou, Liang Bian and Fei Wang

Catalysts 2025, 15(7), 658; https://doi.org/10.3390/catal15070658 (registering DOI) - 6 Jul 2025

Abstract

Ni-based catalysts have been widely used in catalytic reactions by researchers due to their advantages such as abundant resources, high catalytic activity and lower prices than precious metals. However, the problems of easy agglomeration and poor dispersion of Ni-based catalysts have hindered their [...] Read more.

Ni-based catalysts have been widely used in catalytic reactions by researchers due to their advantages such as abundant resources, high catalytic activity and lower prices than precious metals. However, the problems of easy agglomeration and poor dispersion of Ni-based catalysts have hindered their large-scale application. Therefore, it is necessary to select a suitable preparation method to reduce the agglomeration of the catalyst and improve its dispersion. In this paper, the Ni-NiAl₂O₄/tourmaline composite material was prepared by using the microwave hydrothermal reduction method. The most favorable conditions for preparing NiAl₂O₄/tourmaline are as follows: using TEOA as the additive, the microwave hydrothermal temperature is 220 °C, the calcination temperature is 800 °C, and the addition amount of tourmaline is 7.4 wt.%. NiAl₂O₄ has a good dispersion over the surface of tourmaline support and the optimal NiAl₂O₄/tourmaline catalyst exhibits a specific surface area of 106.5 m²/g. Metallic nickel was reduced at 650 °C to further obtain Ni-NiAl₂O₄/tourmaline composites. Finally, the Ni-NiAl₂O₄/tourmaline composites showed significantly improved catalytic dry reforming of methane (DRM) activity compared to Ni-NiAl₂O₄ sample under low-temperature conditions (500–600 °C), meaning that the tourmaline carrier could effectively optimize the low-temperature catalytic performance of Ni-NiAl₂O₄. Full article

(This article belongs to the Special Issue Catalytic Reforming and Hydrogen Production: From the Past to the Future, 2nd Edition)

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17 pages, 527 KiB

Open AccessArticle

Digital Stress Scale (DSC): Development and Psychometric Validation of a Measure of Stress in the Digital Age

by Agathi Argyriadi, Dimitra Katsarou, Athina Patelarou, Kalliopi Megari, Evridiki Patelarou, Stiliani Kotrotsiou, Konstantinos Giakoumidakis, Shabnam Abdoola, Evangelos Mantsos, Efthymia Efthymiou and Alexandros Argyriadis

Int. J. Environ. Res. Public Health 2025, 22(7), 1080; https://doi.org/10.3390/ijerph22071080 (registering DOI) - 6 Jul 2025

Abstract

(1) Background: The integration of digital technologies such as electronic health records (EHRs), telepsychiatry, and communication platforms has transformed the mental health sector a lot compared to in previous years. While these tools enhance service delivery, they also introduce unique stressors. Despite growing [...] Read more.

(1) Background: The integration of digital technologies such as electronic health records (EHRs), telepsychiatry, and communication platforms has transformed the mental health sector a lot compared to in previous years. While these tools enhance service delivery, they also introduce unique stressors. Despite growing concerns, there is no validated instrument specifically designed to measure the digital stress experienced by mental health professionals. (2) Methods: This study involved the development and psychometric validation of the Digital Stress Scale (DSC). The process included item generation through a literature review and qualitative interviews, expert panel validation, and a two-phase statistical evaluation. Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were conducted on responses from 423 licensed mental health professionals using EHRs and digital communication tools. The scale’s reliability and convergent validity were assessed via internal consistency and correlations with established mental health measures. (3) Results: The final DSC included four subscales: digital fatigue, technostress, digital disengagement, and work–life digital boundaries. CFA supported the factor structure (CFI = 0.965, RMSEA = 0.038), and the overall reliability was acceptable (Cronbach’s Alpha = 0.87). Descriptive analysis showed moderate-to-high levels of digital stress (M = 11.94, SD = 2.72). Digital fatigue was the strongest predictor of total stress (β = 1.00, p < 0.001), followed by technostress and work–life boundary violations. All subscales were significantly correlated with burnout (r = 0.72), job dissatisfaction (r = −0.61), and perceived stress (r = 0.68), all with a p < 0.001. (4) Conclusions: The DSC is a valid and reliable tool for assessing digital stress among mental health professionals. Findings point out the urgent need for policy-level interventions to mitigate digital overload, promote healthy work–life boundaries, and enhance digital competency in mental health settings. Full article

(This article belongs to the Special Issue Exploring Mental Health Challenges and Support Systems)

18 pages, 9638 KiB

Open AccessArticle

TCN-MAML: A TCN-Based Model with Model-Agnostic Meta-Learning for Cross-Subject Human Activity Recognition

by Chih-Yang Lin, Chia-Yu Lin, Yu-Tso Liu, Yi-Wei Chen, Hui-Fuang Ng and Timothy K. Shih

Sensors 2025, 25(13), 4216; https://doi.org/10.3390/s25134216 (registering DOI) - 6 Jul 2025

Abstract

Human activity recognition (HAR) using Wi-Fi-based sensing has emerged as a powerful, non-intrusive solution for monitoring human behavior in smart environments. Unlike wearable sensor systems that require user compliance, Wi-Fi channel state information (CSI) enables device-free recognition by capturing variations in signal propagation [...] Read more.

Human activity recognition (HAR) using Wi-Fi-based sensing has emerged as a powerful, non-intrusive solution for monitoring human behavior in smart environments. Unlike wearable sensor systems that require user compliance, Wi-Fi channel state information (CSI) enables device-free recognition by capturing variations in signal propagation caused by human motion. This makes Wi-Fi sensing highly attractive for ambient healthcare, security, and elderly care applications. However, real-world deployment faces two major challenges: (1) significant cross-subject signal variability due to physical and behavioral differences among individuals, and (2) limited labeled data, which restricts model generalization. To address these sensor-related challenges, we propose TCN-MAML, a novel framework that integrates temporal convolutional networks (TCN) with model-agnostic meta-learning (MAML) for efficient cross-subject adaptation in data-scarce conditions. We evaluate our approach on a public Wi-Fi CSI dataset using a strict cross-subject protocol, where training and testing subjects do not overlap. The proposed TCN-MAML achieves 99.6% accuracy, demonstrating superior generalization and efficiency over baseline methods. Experimental results confirm the framework’s suitability for low-power, real-time HAR systems embedded in IoT sensor networks. Full article

(This article belongs to the Special Issue Sensors and Sensing Technologies for Object Detection and Recognition)

21 pages, 2578 KiB

Open AccessArticle

Coverage Hole Recovery in Hybrid Sensor Networks Based on Key Perceptual Intersections for Emergency Communications

by He Li, Shixian Sun, Chuang Dong, Qinglei Qi, Cong Zhao, Zufeng Fu, Peng Yu and Jiajia Liu

Sensors 2025, 25(13), 4217; https://doi.org/10.3390/s25134217 (registering DOI) - 6 Jul 2025

Abstract

Wireless sensor networks (WSNs) have found extensive applications in a variety of fields, including military surveillance, wildlife monitoring, industrial process monitoring, and more. The gradual energy depletion of sensor nodes with limited battery energy leads to the dysfunction of some of the nodes, [...] Read more.

Wireless sensor networks (WSNs) have found extensive applications in a variety of fields, including military surveillance, wildlife monitoring, industrial process monitoring, and more. The gradual energy depletion of sensor nodes with limited battery energy leads to the dysfunction of some of the nodes, thus creating coverage holes in the monitored area. Coverage holes can cause the network to fail to deliver high-quality data and can also affect network performance and the quality of service. Therefore, the detection and recovery of coverage holes are major issues in WSNs. In response to these issues, we propose a method for detecting and recovering coverage holes in wireless sensor networks. This method first divides the network into equally sized units, and then selects a representative node for each unit based on two conditions, called an agent. Then, the percentage of each unit covered by nodes can be accurately calculated and holes can be detected. Finally, the holes are recovered using the average of the key perceptual intersections as the initial value of the global optimal point of the particle swarm optimization algorithm. Simulation experiments show that the algorithm proposed in this paper reduces network energy consumption by 6.68%, decreases the distance traveled by mobile nodes by 8.51%, and increases the percentage of network hole recovery by 2.16%, compared with other algorithms. Full article

(This article belongs to the Section Sensor Networks)

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19 pages, 8205 KiB

Open AccessArticle

The Unilateral Jumping Structures of the Spotted Lanternfly, Lycorma delicatula (Hemiptera: Fulgoridae): A Highly Functional and Integrated Unit

by Xu Chen and Aiping Liang

Biomimetics 2025, 10(7), 444; https://doi.org/10.3390/biomimetics10070444 (registering DOI) - 6 Jul 2025

Abstract

Previous research on the jumping structures of insects with strong leaping abilities mainly focused on overall jumping mechanisms. Our study reveals that the unilateral jumping structures (UJSs) of L. delicatula has relative functional autonomy. The UJSs consist of three distinct but interconnected parts: [...] Read more.

Previous research on the jumping structures of insects with strong leaping abilities mainly focused on overall jumping mechanisms. Our study reveals that the unilateral jumping structures (UJSs) of L. delicatula has relative functional autonomy. The UJSs consist of three distinct but interconnected parts: (1) energy storage component: it comprises the pleural arch and trochanteral depressor muscles, with the deformation zone extending about two-thirds of the pleural arch from the V-notch to the U-notch; (2) coupling component: made up of the coxa and trochanter, it serves as a bridge between the energy and lever components, connecting them via protuberances and pivots; and (3) lever component: it encompasses the femur, tibia, and tarsus. A complete jumping action lasts from 2.4 ms to 4.6 ms. During a jump, the deformation length of the pleural arch is 0.96 ± 0.06 mm. The angles ∠ct (angle between coxa and trochanter), ∠fp (angle between femur and pleural arch), and ∠ft (angle between femur and tibia) change by 57.42 ± 1.60, 101.40 ± 1.59, and 36.06 ± 2.41 degrees, respectively. In this study, we abstracted the jumping structures of L. delicatula and identified its critical components. The insights obtained from this study are anticipated to provide valuable inspiration for the design and fabrication of biomimetic jumping mechanisms. Full article

(This article belongs to the Special Issue Biomechanics and Biomimetics for Insect-Inspired MAVs)

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