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23 pages, 7333 KB  
Article
Elucidation of the Biological Function and Early-Infection Cell Cycle Regulatory Mechanism of Avocado-Infecting Colletotrichum fructicola
by Sizhen Liu, Longhui Huang, Qianlong Sun, Yilong Man, Yangdan Yuan, Min Kuang, Yiyin Fan, Shankui Yuan, Yonghua Zhu and Xinqiu Tan
Foods 2026, 15(8), 1295; https://doi.org/10.3390/foods15081295 - 9 Apr 2026
Abstract
Persea americana (avocado) is a fruit rich in nutrients; however, its industry is facing major threats from pathogen infection. Here, we clearly identified Colletotrichum fructicola as the pathogen causing avocado diseases in Pu’er City, Yunnan Province. However, the biological characteristics, genetic transformation system, [...] Read more.
Persea americana (avocado) is a fruit rich in nutrients; however, its industry is facing major threats from pathogen infection. Here, we clearly identified Colletotrichum fructicola as the pathogen causing avocado diseases in Pu’er City, Yunnan Province. However, the biological characteristics, genetic transformation system, and early cell cycle regulation of this pathogen remained unclear. In this study, C. fructicola exhibited a maximum growth rate on complete medium (CM), with the conidial yield reaching 2 × 105 conidia/mL after 24 h in liquid CM. Conidia of C. fructicola had nearly fully germinated at 4 h post-inoculation (hpi), with the appressorium formation rate exceeding 95% at 12 hpi. We also established a PEG-CaCl2-mediated genetic transformation system. The GFP-tagged transformants showed no significant differences in core biological function from the wild type. Using eGFP labeling, we visually elucidated the early cell cycle regulation of C. fructicola. Furthermore, cell cycle inhibitor assays demonstrated that C. fructicola conidial germination is independent of nuclear division and relies on cytoskeletal modulation, whereas appressorium formation and mycelial expansion require functional cell cycle regulation. This is probably the first study to systematically elucidate the cell cycle regulatory characteristics of C. fructicola isolated from avocado, and to successfully develop its genetic transformation system. These results provide important theoretical and technical support for the formulation of integrated control strategies against C. fructicola, as well as facilitating the sustainable development of the avocado industry. Full article
(This article belongs to the Section Food Toxicology)
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21 pages, 337 KB  
Article
Black Box Optimization for Ergodic Systems in Markov Chains
by Julio B. Clempner
Mathematics 2026, 14(8), 1246; https://doi.org/10.3390/math14081246 - 9 Apr 2026
Abstract
This paper studies a black-box methodology for optimizing ergodic stochastic systems, focusing on the construction of scalar measures that reliably indicate progress toward optimality. Our starting point is a state-value quantity that inherently exhibits oscillatory behavior and does not converge under standard conditions. [...] Read more.
This paper studies a black-box methodology for optimizing ergodic stochastic systems, focusing on the construction of scalar measures that reliably indicate progress toward optimality. Our starting point is a state-value quantity that inherently exhibits oscillatory behavior and does not converge under standard conditions. We show that, despite its fluctuations, this quantity admits a recursive representation derived from a one-step-ahead fixed-local-optimal policy. The approach relies on identifying a Lyapunov-like function whose evolution reflects the long-run behavior of the system without requiring explicit knowledge of its internal dynamics. Such a function provides a monotonic indicator—non-increasing over time—that remains valid for any initial probability distribution. Whenever an optimal trajectory of the Markov chain exists, the proposed method guarantees convergence to it. We also provide a constructive procedure for obtaining the Lyapunov-like function and validate the methodology through theoretical analysis and numerical simulations. Full article
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9 pages, 415 KB  
Article
Association Between Trauma Mechanism and Mandibular Fracture Pattern: A 13-Year Retrospective Analysis at a Regional Trauma Center
by Graciela Ana Giannunzio, Jose Mariano Astigueta, Sthefania Johana Lucero, Ariana Gimena Labachuk and Carlos Alberto Isnado Bolivar
Craniomaxillofac. Trauma Reconstr. 2026, 19(2), 22; https://doi.org/10.3390/cmtr19020022 - 9 Apr 2026
Abstract
The mandible, due to its anatomical position, mobility, and functional role, is one of the bones most frequently involved in maxillofacial trauma, with fracture patterns influenced by impact mechanisms and anatomical characteristics. This study aimed to analyse the relationship between trauma mechanisms and [...] Read more.
The mandible, due to its anatomical position, mobility, and functional role, is one of the bones most frequently involved in maxillofacial trauma, with fracture patterns influenced by impact mechanisms and anatomical characteristics. This study aimed to analyse the relationship between trauma mechanisms and affected anatomical subsites in patients with isolated mandibular fractures treated at a regional public hospital in Buenos Aires Province. A retrospective cross-sectional observational study was conducted using medical records, surgical reports, and diagnostic imaging of patients treated between 2011 and 2024. Isolated mandibular fractures were included, while pathological fractures, dentoalveolar injuries, and cases with incomplete data were excluded. Trauma mechanisms were classified as interpersonal aggression, vehicular accidents, falls from height, contact sports, and blows with blunt objects. Interpersonal aggression was the most frequent trauma mechanism, followed by falls from height and vehicular accidents. The mandibular angle, parasymphysis, and condyle were the most commonly affected anatomical sites. Multivariable analysis showed a higher probability of condylar fractures in falls from height (OR = 4.75; 95% CI: 2.24–10.3; p < 0.001) and vehicular accidents (OR = 3.02; 95% CI: 1.28–7.13; p = 0.01). Falls were also associated with a lower probability of mandibular angle fractures (OR = 0.16; 95% CI: 0.06–0.36; p < 0.001), while blunt object trauma showed a positive association with mandibular body fractures (OR = 3.12; 95% CI: 1.04–8.95; p = 0.04). These findings indicate that trauma mechanisms influence the anatomical distribution of mandibular fractures, providing relevant information for diagnostic assessment and surgical planning. Full article
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16 pages, 778 KB  
Systematic Review
Surgical Versus Conservative Management for Carpal Tunnel Syndrome: An Updated Systematic Review of Randomised Trials
by Sara Masiero, Pasquale Arcuri, Paolo Boccolari, Elena Zorzi, Alessandro Vio, Tracy Fairplay, Davide Zanin, Fabio Vita, Danilo Donati and Roberto Tedeschi
Brain Sci. 2026, 16(4), 399; https://doi.org/10.3390/brainsci16040399 - 8 Apr 2026
Abstract
Background: Carpal tunnel syndrome (CTS) is one of the most common entrapment neuropathies. While surgical decompression is widely considered the definitive treatment, conservative options remain clinically relevant, particularly for symptom relief and functional recovery in the short term. Objectives: To update the evidence [...] Read more.
Background: Carpal tunnel syndrome (CTS) is one of the most common entrapment neuropathies. While surgical decompression is widely considered the definitive treatment, conservative options remain clinically relevant, particularly for symptom relief and functional recovery in the short term. Objectives: To update the evidence comparing surgical versus non-surgical interventions for CTS, assessing pain, function, and clinical recovery. Design: Systematic review of randomised controlled trials (RCTs). Data Sources and Methods: Six databases (CENTRAL, MEDLINE, Embase, Cochrane Neuromuscular Register, ClinicalTrials.gov, and WHO ICTRP) were searched for RCTs published between November 2022 and January 2025. Risk of bias was assessed with RoB 2.0 and certainty of evidence with GRADE. Due to clinical heterogeneity, a narrative synthesis was performed. Results: Four RCTs (n = 1158) were included. Corticosteroid injection and percutaneous electrical nerve stimulation (PENS) appeared to provide faster symptom relief than surgery at short-term follow-up. However, surgery was associated with a higher probability of sustained recovery at 12–18 months (RR 1.36; 95% CI 1.19–1.56). Evidence for PENS was limited to one female-only trial, which restricts generalisability. Certainty of evidence was moderate for long-term outcomes and low for short-term results and safety. Conclusions: The available evidence suggests that surgery may offer more durable long-term recovery, whereas corticosteroids and PENS may be useful for short-term symptom relief. These findings should be interpreted with caution given the limited number of trials and the risk of bias in most included studies. Treatment choice should align with patient goals and recovery timelines. Registration: PROSPERO (CRD420250650789). Full article
(This article belongs to the Section Neurosurgery and Neuroanatomy)
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36 pages, 595 KB  
Review
Metabolic Myokines and Adipokines in the Follicular Microenvironment: Implications for Oocyte Competence and IVF Outcomes
by Charalampos Voros, Fotios Chatzinikolaou, Georgios Papadimas, Ioannis Papapanagiotou, Athanasios Karpouzos, Aristotelis-Marios Koulakmanidis, Diamantis Athanasiou, Kyriakos Bananis, Antonia Athanasiou, Aikaterini Athanasiou, Charalampos Tsimpoukelis, Maria Anastasia Daskalaki, Christina Trakateli, Nana Kojo Koranteng, Nikolaos Thomakos, Panagiotis Antsaklis, Dimitrios Loutradis and Georgios Daskalakis
Int. J. Mol. Sci. 2026, 27(8), 3344; https://doi.org/10.3390/ijms27083344 - 8 Apr 2026
Abstract
Oocyte competency is a crucial determinant of fertilisation success and the initial development of embryos in assisted reproductive technologies. The metabolic and biochemical environment of the ovarian follicle is crucial for determining oocyte developmental potential, alongside genetic integrity. The follicular microenvironment includes a [...] Read more.
Oocyte competency is a crucial determinant of fertilisation success and the initial development of embryos in assisted reproductive technologies. The metabolic and biochemical environment of the ovarian follicle is crucial for determining oocyte developmental potential, alongside genetic integrity. The follicular microenvironment includes a complex network of signalling chemicals that regulate mitochondrial activity, steroidogenesis, oxidative balance, and cellular energy metabolism. Recently, metabolic hormones originating from adipose tissue and skeletal muscle, namely, adipokines and myokines, have received considerable focus as crucial regulators of ovarian physiology. Adiponectin, irisin, and the recently identified hormone asprosin have emerged as crucial metabolic regulators influencing granulosa cell activity, mitochondrial bioenergetics, insulin signalling pathways, and redox homeostasis inside the follicular niche. Adiponectin mostly provides metabolic protection by activating AMP-activated protein kinase (AMPK) and improving insulin sensitivity, which in turn enhances mitochondrial efficiency and steroidogenic function in granulosa cells. Irisin, derived from the breakdown of fibronectin type III domain-containing protein 5 (FNDC5), aids the developing oocyte by facilitating mitochondrial biogenesis, augmenting oxidative phosphorylation, and altering cellular defence mechanisms against oxidative stress. Conversely, asprosin has been associated with glucogenic signalling, metabolic stress, and probable mitochondrial malfunction, suggesting a possible relationship between systemic metabolic problems and negative reproductive consequences. Clinical and experimental research indicate that the levels of these metabolic regulators in follicular fluid may correlate with ovarian response, oocyte quality, fertilisation rates, and embryo development during in vitro fertilisation cycles. This review consolidates current molecular, cellular, and clinical information, clarifying the pathways by which adipokines and myokines influence follicular metabolism and impact oocyte competency. Understanding the metabolic connections between systemic endocrine signals and the follicular milieu may provide novel indicators for reproductive prognosis and provide new treatment targets to improve assisted reproduction outcomes. Full article
(This article belongs to the Collection Advances in Cell and Molecular Biology)
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22 pages, 1212 KB  
Article
Echocardiographic Markers and Outcomes in End-Stage Liver Disease
by Teodora Radu, Speranta Maria Iacob and Liliana Gheorghe
J. Clin. Med. 2026, 15(7), 2791; https://doi.org/10.3390/jcm15072791 - 7 Apr 2026
Abstract
Background: In end-stage liver disease (ESLD), cardiovascular changes are frequent and relate to the presence of hyperdynamic circulation. In 2019, diagnostic criteria for cirrhotic cardiomyopathy (CCM) were updated to include tissue Doppler and speckle tracking imaging in defining left ventricle (LV) systolic and [...] Read more.
Background: In end-stage liver disease (ESLD), cardiovascular changes are frequent and relate to the presence of hyperdynamic circulation. In 2019, diagnostic criteria for cirrhotic cardiomyopathy (CCM) were updated to include tissue Doppler and speckle tracking imaging in defining left ventricle (LV) systolic and diastolic dysfunction. Evaluation of diastolic function remains challenging, with frequent indeterminate cases and emerging evidence of worse prognosis. The aim of the present study was to evaluate the prevalence of LV systolic and diastolic dysfunction in cirrhosis, in correlation with liver disease severity and potential prognostic implications. Methods: We performed an observational, retrospective, non-randomized, single-center study that included 99 cirrhotic patients evaluated for liver transplant (LT) in a tertiary center. Liver disease severity and complications were analyzed with survival and echocardiography data to determine potential correlations with prognosis. For statistical analysis, IBM® SPSS® Statistics version 20 (Chicago, IL, USA) was utilized. A two-sided p-value < 0.05 was considered statistically significant. Results: Left atrial (LA) volume index (r = 0.230, p = 0.022), LA reservoir strain (r = 0.291, p = 0.003), and LA contraction strain absolute value (r = 0.223, p = 0.027) positively correlated with the severity of liver disease expressed by MELD Na score. LA dilation (≥34 mL/m2) was the most common echocardiographic finding. It was present in 69.7% of patients, with one third having severe LA dilation (>45 mL/m2), which was associated with worse survival (log rank p = 0.019). LA contraction strain with an absolute value higher than 16% was also associated with worse survival (log rank p = 0.024). In multivariable Cox analysis, only MELD-Na and LA volume index remained independently associated with mortality. Diastolic dysfunction appeared more prevalent among the non-surviving patients irrespective of the diagnostic criteria used (p = 0.023 for American Society of Echocardiography 2016 criteria; p = 0.032 for CCM 2019 criteria). On binomial logistic regression, the presence of significant diastolic dysfunction (>grade 1) was associated with an increased probability of composite end-point of death or LT in the presence of liver disease severity confounders. The use of the LA stiffness index in discerning diastolic function in patients with standard inconclusive evaluation may warrant further investigation. Conclusions: Echocardiographic alterations, particularly LA enlargement, are associated with liver disease severity and clinical outcomes in ESLD. These findings are hypothesis-generating and suggest a potential role for echocardiography in risk stratification, warranting validation in larger prospective studies. Full article
(This article belongs to the Section Cardiology)
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25 pages, 4504 KB  
Article
Discrete Element Modelling of Thermal Evolution of Forsmark Repository for Spent Nuclear Fuel Disposal and Long-Term Response of Discrete Fracture Network
by Jeoung Seok Yoon, Haimeng Shen, Arno Zang and Flavio Lanaro
Appl. Sci. 2026, 16(7), 3592; https://doi.org/10.3390/app16073592 - 7 Apr 2026
Abstract
Long-term safety assessment of deep geological repositories for spent nuclear fuel requires explicit evaluation of thermo-mechanical (TM) processes induced by decay heat and their influence on fractured host rock. A safety-relevant, though low-probability, scenario concerns shear reactivation of fractures intersecting deposition holes, which [...] Read more.
Long-term safety assessment of deep geological repositories for spent nuclear fuel requires explicit evaluation of thermo-mechanical (TM) processes induced by decay heat and their influence on fractured host rock. A safety-relevant, though low-probability, scenario concerns shear reactivation of fractures intersecting deposition holes, which could compromise canister integrity if displacement exceeds design limits. This study presents a three-dimensional discrete element modelling approach to analyze the thermal evolution of the Forsmark repository (Sweden) and the associated long-term response of a discrete fracture network (DFN) during the post-closure phase. The model explicitly represents repository panel, deterministic deformation zones, and a stochastically generated fracture network embedded in a bonded particle assembly representing the rock for Particle Flow Code (PFC) numerical simulations. Time-dependent heat release from spent nuclear fuel canisters is implemented using a physically based decay power function. A deposition panel-scale heat-loading formulation accounts for deposition-hole and tunnel spacing. Two emplacement scenarios are analyzed: (a) a simultaneous all-panel heating scenario, used as a conservative bounding case, and (b) a sequential panel heating scenario representing staged emplacement and closure. The simulations show that temperature and thermally induced stress evolution are sensitive to the emplacement and closure sequence. Sequential heating produces a more gradual thermal build-up and lower peak temperatures than simultaneous heating, indicating that thermal and stress perturbations in the host rock can be influenced not only through repository design, but also by operational strategy. Thermally induced fracture shear displacement displays a systematic temporal response. Fractures located within the deposition panel footprint develop shear displacement rapidly during the early post-closure period, reaching peak values at approximately 200 years, followed by gradual relaxation as temperatures decline. The average peak shear displacement on fractures is on the order of 2–3 mm, while fractures outside the panel footprint show smaller early-time displacements and a more prolonged long-term response. All simulated shear displacements remain more than one order of magnitude below the commonly cited canister damage threshold for Forsmark of approximately 50 mm, even for the conservative simultaneous heating case. These results indicate that thermally induced fracture shear is unlikely to cause direct mechanical damage to canisters. At the same time, the persistence of residual shear displacement after heating implies permanent fracture dilation, which may influence long-term hydraulic properties and indirectly affect processes such as groundwater flow and canister corrosion. The modelling framework and results presented here were conducted for review purposes independently from the Swedish safety case, and provide a mechanistic basis for evaluating thermally induced fracture deformation in crystalline rock repositories and contribute to bounding the role of thermo-mechanical processes in the safety assessment of spent nuclear fuel disposal at Forsmark. Full article
(This article belongs to the Special Issue Progress and Challenges of Rock Engineering)
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26 pages, 1349 KB  
Article
ICOA: An Improved Coati Optimization Algorithm with Multi-Strategy Enhancement for Global Optimization and Engineering Design Problems
by Xiangyu Cheng, Min Zhou, Liping Zhang and Zikai Zhang
Biomimetics 2026, 11(4), 254; https://doi.org/10.3390/biomimetics11040254 - 7 Apr 2026
Abstract
Metaheuristic optimization algorithms have attracted considerable research interest for solving complex optimization problems, yet many existing algorithms suffer from premature convergence and an inadequate balance between exploration and exploitation. The Coati Optimization Algorithm (COA) is a recently proposed nature-inspired metaheuristic that models the [...] Read more.
Metaheuristic optimization algorithms have attracted considerable research interest for solving complex optimization problems, yet many existing algorithms suffer from premature convergence and an inadequate balance between exploration and exploitation. The Coati Optimization Algorithm (COA) is a recently proposed nature-inspired metaheuristic that models the hunting and escape behaviors of coatis; however, it exhibits limited search diversity and tends to stagnate in local optima on high-dimensional, multimodal landscapes. This paper proposes an Improved Coati Optimization Algorithm (ICOA) that integrates four complementary enhancement strategies: (1) a Dynamic Adaptive Step-Size strategy that combines Lévy flights with Student’s t-distribution perturbations for heavy-tailed exploration; (2) a Population-Adaptive Dynamic Perturbation strategy that incorporates differential evolution operators with fitness-proportional scaling; (3) an Iterative-Cyclic Differential Perturbation strategy that employs sinusoidal scheduling and population-differential guidance; and (4) a Cosine-Adaptive Gaussian Perturbation strategy for refined exploitation with time-decaying intensity. ICOA is evaluated on 29 CEC2017, 10 CEC2020, and 12 CEC2022 benchmark functions across dimensions ranging from 10 to 100, compared against seven state-of-the-art algorithms in each benchmark suite. A statistical analysis using the Friedman test and the Wilcoxon rank-sum test confirms that ICOA achieves overall rank 1 on all three benchmark suites, with Friedman mean ranks of 1.207 (CEC2017, D=100), 1.000 (CEC2020, D=10), and 2.208 (CEC2022, D=10); the CEC2020 result should be interpreted in the context of its low dimensionality. A scalability analysis across four dimensionalities (10D, 30D, 50D, 100D) demonstrates consistent first-place rankings with mean ranks between 1.000 and 1.207. An ablation study and a sensitivity analysis of the strategy activation probability validate the contribution of each individual strategy and the optimality of the 50% activation setting. Furthermore, ICOA achieves the best results on all six constrained engineering design problems tested, with all improvements confirmed as statistically significant (p<0.05). Full article
(This article belongs to the Section Biological Optimisation and Management)
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21 pages, 31287 KB  
Article
A Cross-Scale Study of Data-Driven Micro-to-Macro Mechanical Heterogeneity in Sandstone
by Binwei Xia, Yulin Zhang, Xinqin Xu, Lei Wang, Rui Li and Xiong Zheng
Appl. Sci. 2026, 16(7), 3589; https://doi.org/10.3390/app16073589 - 7 Apr 2026
Abstract
Tight sandstone gas development is largely governed by mineral composition and micromechanical heterogeneity. This study proposes a cross-scale method integrating these two factors to characterize macroscopic sandstone heterogeneity. First, a CNN–Transformer model was trained on thin-section images to identify mineral types and contents. [...] Read more.
Tight sandstone gas development is largely governed by mineral composition and micromechanical heterogeneity. This study proposes a cross-scale method integrating these two factors to characterize macroscopic sandstone heterogeneity. First, a CNN–Transformer model was trained on thin-section images to identify mineral types and contents. Second, probability density functions of Young’s modulus for each mineral were derived from nanoindentation data, and stochastic sampling was used to assign mechanical properties to mineral grains in an FDEM-GBM uniaxial compression model. Finally, numerical results validated against experiments show that the random spatial distribution of micromechanical parameters leads to a normal distribution of the macroscopic Young’s modulus. Decreasing high-strength mineral content reduces the mean Young’s modulus while increasing its standard deviation, indicating greater mechanical heterogeneity, with cracks preferentially propagating in low-strength minerals. Mineral composition and content are the primary controls on macroscopic behavior, while micromechanical heterogeneity plays a secondary role. A brittleness index integrating mineral composition and multi-scale Young’s modulus distribution is proposed, providing a theoretical basis for evaluating heterogeneity and fracability in tight sandstone reservoirs. Full article
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33 pages, 947 KB  
Article
Global Dynamics for a Distributed Delay SVEIR Model for Measles Transmission with Imperfect Vaccination: A Threshold Analysis
by Mohammed H. Alharbi and Ali Rashash Alzahrani
Mathematics 2026, 14(7), 1219; https://doi.org/10.3390/math14071219 - 5 Apr 2026
Viewed by 127
Abstract
Measles remains a significant public health threat despite widespread vaccination, with recent resurgences driven by vaccine hesitancy and coverage gaps. Existing mathematical models often fail to capture the substantial temporal heterogeneity in incubation periods, vaccine-induced protection, and recovery processes that characterize measles transmission. [...] Read more.
Measles remains a significant public health threat despite widespread vaccination, with recent resurgences driven by vaccine hesitancy and coverage gaps. Existing mathematical models often fail to capture the substantial temporal heterogeneity in incubation periods, vaccine-induced protection, and recovery processes that characterize measles transmission. We develop and analyze an SVEIR epidemic model incorporating four independent distributed time delays with exponential survival factors, capturing the realistic variability in these epidemiological processes. The model features compartment-specific mortality rates, disease-induced mortality, and imperfect vaccination with failure probability θ. Using next-generation matrix methods adapted for delay kernels, we derive the delay-dependent reproduction number R0d and prove, via systematic construction of Volterra-type Lyapunov functionals, that it constitutes a sharp threshold: the disease-free equilibrium is globally asymptotically stable when R0d1, while a unique endemic equilibrium emerges and is globally stable when R0d>1. Normalized forward sensitivity analysis reveals that the transmission rate β and recruitment rate Λ exhibit maximal positive elasticity, while the vaccination rate p, vaccine failure probability θ, and incubation delay τ3 possess the largest negative elasticities. Critically, τ3 exerts exponential influence via en3τ3, making interventions that delay infectiousness—such as post-exposure prophylaxis—unusually potent. We derive an explicit expression for the critical delay τ3cr at which R0d=1, demonstrating that prolonging the effective incubation period sufficiently can shift the system from endemic persistence to extinction. Numerical simulations using Dirac delta kernels confirm all theoretical predictions. These findings provide three actionable insights for public health: (1) maintaining high vaccination coverage among new birth cohorts remains paramount; (2) improving vaccine quality (reducing θ) yields substantial returns; and (3) the incubation delay represents a quantifiable, measurable target for evaluating the population-level impact of time-sensitive interventions. The framework is broadly applicable to infectious diseases characterized by significant temporal heterogeneity. Full article
(This article belongs to the Special Issue Advances in Epidemiological and Biological Systems Modeling)
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29 pages, 1107 KB  
Article
Secure Uplink Transmission in UAV-Assisted Dual-Orbit SAGIN over Mixed RF-FSO Links
by Zhan Xu and Chunshuai Ma
Aerospace 2026, 13(4), 341; https://doi.org/10.3390/aerospace13040341 - 4 Apr 2026
Viewed by 142
Abstract
To meet the need for global coverage, space–air–ground integrated networks (SAGINs) are crucial, but the openness of wireless links makes communications vulnerable to eavesdropping. This paper investigates the physical layer security (PLS) of uplink transmissions in a cooperative dual-hop SAGIN. The system comprises [...] Read more.
To meet the need for global coverage, space–air–ground integrated networks (SAGINs) are crucial, but the openness of wireless links makes communications vulnerable to eavesdropping. This paper investigates the physical layer security (PLS) of uplink transmissions in a cooperative dual-hop SAGIN. The system comprises a ground source with a directional antenna, an unmanned aerial vehicle (UAV) relay cluster, and a low Earth orbit (LEO) satellite. Utilizing stochastic geometry, we model the spatial randomness of terrestrial eavesdroppers and the multi-layered dual-orbital LEO destination. To combat mixed radio-frequency (RF) and free-space optical (FSO) fading, multiple relay selection and maximum ratio combining (MRC) are integrated into the UAV cluster. We analytically derive the piecewise probability density function for the FSO link distance, obtaining exact closed-form expressions for the end-to-end secrecy outage probability (SOP). Monte Carlo simulations strictly validate the derivations. The results demonstrate that while increasing available relays and antennas enhances PLS via spatial diversity, a security bottleneck restricts the RF-FSO architecture under high-transmit power regimes, generating asymptotic secrecy floors. These findings provide explicit theoretical guidelines for the secure design and parameter optimization of future SAGINs. Full article
(This article belongs to the Section Astronautics & Space Science)
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21 pages, 2107 KB  
Article
Differential Associations of Internal and Residential Lead Exposure Pathways with Body Mass Index: A Mixture Analysis of Biomarkers and Household Dust
by Zaniyah Ward and Emmanuel Obeng-Gyasi
Environments 2026, 13(4), 200; https://doi.org/10.3390/environments13040200 - 4 Apr 2026
Viewed by 269
Abstract
Background: Human lead exposure is a multi-pathway phenomenon that integrates internal biological burden with persistent residential environmental reservoirs. Although individual lead metrics have been linked to cardiometabolic dysfunction, current research often fails to capture the ‘exposome’ reality of joint, nonlinear, and interaction-dependent effects [...] Read more.
Background: Human lead exposure is a multi-pathway phenomenon that integrates internal biological burden with persistent residential environmental reservoirs. Although individual lead metrics have been linked to cardiometabolic dysfunction, current research often fails to capture the ‘exposome’ reality of joint, nonlinear, and interaction-dependent effects on metabolic outcomes like BMI. Objectives: To evaluate associations between biological (blood and urinary) and residential dust (window and floor) lead measures and BMI, and to characterize nonlinear and interaction-dependent mixture effects using Bayesian Kernel Machine Regression (BKMR). Methods: We analyzed data from NHANES 2001–2002, a nationally representative survey of the U.S. noninstitutionalized civilian population. Window and floor dust lead (µg/ft2) were obtained from the NHANES household dust component, and blood lead (µg/dL) and urinary lead (µg/L) were measured using standardized NHANES laboratory protocols. BMI was calculated from measured height and weight. Missing data were addressed using multivariate imputation by chained equations. Descriptive statistics and multivariable linear regression were used to estimate adjusted associations between individual lead metrics and BMI, controlling for age, gender, income, race/ethnicity, and education. BKMR was then applied to evaluate joint mixture effects, estimate univariate and bivariate exposure–response functions, and quantify relative exposure importance using posterior inclusion probabilities (PIPs). Results: In covariate-adjusted linear regression, blood lead (β = −0.485; 95% CI: −0.566, −0.405; p < 0.001) and window dust lead (β = −0.00047; 95% CI: −0.00067, −0.00026; p < 0.001) were inversely associated with BMI, whereas floor dust lead was positively associated (β = 0.258; 95% CI: 0.209, 0.306; p < 0.001). Urinary lead was inversely but not significantly associated with BMI (β = −0.111; 95% CI: −0.235, 0.013; p = 0.079). In BKMR, blood lead was the dominant contributor, with a posterior inclusion probability (PIP; proportion of iterations in which an exposure is selected) of 1.00. Window dust lead showed modest inclusion (PIP = 0.26), whereas urinary and floor dust lead were not selected (PIP = 0.00). Exposure–response functions indicated modest nonlinearity for blood lead and greater divergence for the blood lead–window dust lead pairing at higher exposure levels. The overall mixture effect declined across increasing joint exposure quantiles, crossing the null near the median and becoming increasingly negative at higher mixture levels. Conclusions: In our study, lead metrics showed heterogeneous associations with BMI, and BKMR indicated that internal lead burden (blood lead) primarily drove mixture-related BMI patterns, with evidence that window dust lead may modify mixture effects at higher co-exposure levels. These findings support evaluating multiple lead exposure pathways jointly and using flexible mixture models to capture nonlinear and interaction-dependent relationships with BMI. Full article
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30 pages, 11760 KB  
Article
A Multi-Dimensional Indicator Framework for Peri-Urban Area Delineation: Insights from Equal- and AHP-Weighted Models in Java, Indonesia
by Ziyue Wang, Adhitya Marendra Kiloes, Md. Ali Akber, Bagus Setiabudi Wiwoho and Ammar Abdul Aziz
Remote Sens. 2026, 18(7), 1062; https://doi.org/10.3390/rs18071062 - 2 Apr 2026
Viewed by 289
Abstract
Peri-urban areas (PUAs), as transitional zones between urban and rural regions, play a critical role in supporting food systems and agricultural livelihoods, yet they are increasingly pressured by rapid urban expansion. Reliable spatial delineation of PUAs remains challenging, as administrative boundaries often fail [...] Read more.
Peri-urban areas (PUAs), as transitional zones between urban and rural regions, play a critical role in supporting food systems and agricultural livelihoods, yet they are increasingly pressured by rapid urban expansion. Reliable spatial delineation of PUAs remains challenging, as administrative boundaries often fail to capture their functional and spatial heterogeneity. This study proposes a multi-dimensional, spatially explicit framework to delineate peri-urban areas using Indonesia as a case study. Eighteen indicators representing six analytical dimensions—land use/land cover, economic, demographic, infrastructural, spatial accessibility, and landscape structure—were derived from remote sensing and GIS-based data sources and integrated into a composite scoring system using equal-weighted and AHP-weighted approaches. The framework was applied to four major cities on Java Island (Jakarta, Surabaya, Bandung, and Yogyakarta) to generate continuous peri-urban probability surfaces, which were validated using expert surveys across 25 districts in the Jakarta and Bandung metropolitan areas. The results show that the framework effectively captures the spatial heterogeneity and gradients of peri-urban areas, with the equal-weighted approach exhibiting statistically significant agreement with expert assessments (Pearson’s r = 0.517, p = 0.008; Spearman’s ρ = 0.522, p = 0.008; Kendall’s τ = 0.387, p = 0.008), consistently outperforming the AHP-weighted model across all validation metrics. The proposed approach provides a transferable spatial mapping framework for monitoring peri-urban dynamics in rapidly urbanizing regions using remote sensing and GIS. Full article
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17 pages, 3898 KB  
Article
Stochastic Assessment of Fracture Toughness and Reliability in Anisotropic Boride Layers on Ti6Al4V: A Monte Carlo-Based Mixed-Mode Model
by German Anibal Rodríguez Castro
Mathematics 2026, 14(7), 1186; https://doi.org/10.3390/math14071186 - 2 Apr 2026
Viewed by 245
Abstract
In the realm of computational biomechanics, quantifying the reliability of surface-engineered implants is critical yet challenging due to material anisotropy and experimental limitations. Standard deterministic approaches often fail to capture the failure probability of brittle coatings, compromising the accuracy of lifespan predictions. This [...] Read more.
In the realm of computational biomechanics, quantifying the reliability of surface-engineered implants is critical yet challenging due to material anisotropy and experimental limitations. Standard deterministic approaches often fail to capture the failure probability of brittle coatings, compromising the accuracy of lifespan predictions. This study’s originality lies in a stochastic framework that addresses titanium boride data scarcity using a geometric decision node (GDN). By autonomously switching between Palmqvist and Radial-Median regimes, the GDN eliminates deterministic bias and provides a failure-probability-based reliability assessment, thereby surpassing the limitations of conventional models. The evaluation was carried out on powder-pack borided Ti6Al4V layers produced at 1000 °C (10, 15, and 20 h). By combining instrumented Berkovich nanoindentation (N = 14, hardness scatter 17.6–34.8 GPa) with a Monte Carlo simulation algorithm (n = 10,000), we successfully modeled the stochastic brittle failure of the coating. The computational model, governed by a multivariate joint probability density function (JPDF), revealed a mixed-mode fracture mechanism where 77.9% of the virtual population developed radial cracks while 22.1% re mained in the Palmqvist regime. Weibull statistical analysis yielded a characteristic toughness of 2.25 MPa·m1/2 and a low modulus of m = 1.58. This low modulus mathematically quantifies the coating’s sensitivity to microstructural defects, demonstrating that probabilistic algorithms—rather than mean-value deterministic calculations—are essential for ensuring the structural integrity of borided components in biomechanical design applications. Full article
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17 pages, 749 KB  
Article
Comparative Performance of SARC-F, SARC-CalF, SARC-F + EBM, and Ishii Score for Detecting Sarcopenia in Hospitalised Geriatric Patients
by Ioana Daniela Rus, Vlad Ionuț Nechita, Lucreția Avram, Dana Crișan, Cristina Pamfil, Laura Muntean, Elisabeta Ioana Hirișcău and Valer Donca
J. Clin. Med. 2026, 15(7), 2663; https://doi.org/10.3390/jcm15072663 - 1 Apr 2026
Viewed by 357
Abstract
Background/Objectives: Sarcopenia is a progressive decline in skeletal muscle strength and mass, leading to decreased functionality, metabolic disorders, morbidity, and mortality. There are a number of sarcopenia screening tools, such as the SARC-F questionnaire (that includes noting strength, assistance with walking, ability to [...] Read more.
Background/Objectives: Sarcopenia is a progressive decline in skeletal muscle strength and mass, leading to decreased functionality, metabolic disorders, morbidity, and mortality. There are a number of sarcopenia screening tools, such as the SARC-F questionnaire (that includes noting strength, assistance with walking, ability to raise from the chair, climb stairs, and falls), with its augmented forms that have added calf circumference (SARC-CalF), BMI and age (SARC-F + EBM), and the Ishii score, which show variable performance across populations. However, these were developed and validated mostly in Asian cohorts. To evaluate the diagnostic accuracy of these tools for the European Working Group on Sarcopenia in Older People (EWGSOP2), as well as define sarcopenia in hospitalized East European older adults, with sex and obesity stratification. Methods: Sarcopenia was diagnosed using the EWGSOP2. ROC analyses with DeLong tests assessed SARC-F, SARC-CalF, SARC-F + EBM, and the Ishii score in 278 Romanian inpatients (probable sarcopenia n = 201/278, 72.3%; confirmed n = 77/278, 27.7%). Results: Probable sarcopenia was noted as good-excellent discrimination against across all tools (AUCs 0.764–0.812); confirmed sarcopenia was noted as SARC-CalF superior (AUC = 0.743), followed by SARC-F + EBM (0.697), the Ishii score as moderate (0.667), and SARC-F was limited (0.591; p < 0.001 vs. augmented). SARC-CalF optimal cut-offs varied significantly: 4–6 (probable) vs. ≥11 (confirmed). Sex-stratified outcomes had excellent probable detection in both sexes, and this was confirmed to be superior in men. The Ishii score thresholds were 152/244 vs. Asian ≥ 105/120. Obesity required higher cut-offs with high NPVs (77–100%), confirming rule-out utility and SARC-F + EBM performing the best, both in the obesity and sarcopenic obesity subgroups (AUCs 0.742, 0.964). Conclusions: Augmented SARC-F scores outperformed the original SARC-F for confirmed sarcopenia in multimorbid Europeans, with SARC-F CalF having the best performance overall. Population-specific (sex/obesity) data-driven thresholds are essential, especially for the Ishii score, as this first Romanian validation reveals limitations of Asian norms in European cohorts, thus advocating for European recalibration. Full article
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