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8 pages, 5466 KB  
Case Report
A 350 kb NEXMIF Microdeletion Identified by Chromosomal Microarray in an Adult Patient with Jeavons Syndrome
by Mario Benvenuto, Umberto Costantino, Pietro Palumbo, Massimo Carella, Marco Castori, Giuseppe d’Orsi and Orazio Palumbo
Genes 2026, 17(4), 448; https://doi.org/10.3390/genes17040448 - 13 Apr 2026
Viewed by 138
Abstract
Background: Pathogenic variants in the NEXMIF gene have been linked to a broad neurodevelopmental phenotype, encompassing autism spectrum disorder, intellectual disability, and epilepsy. Among epileptic manifestations, Jeavons Syndrome was observed in 24% of affected females in the largest cohort of NEXMIF-related [...] Read more.
Background: Pathogenic variants in the NEXMIF gene have been linked to a broad neurodevelopmental phenotype, encompassing autism spectrum disorder, intellectual disability, and epilepsy. Among epileptic manifestations, Jeavons Syndrome was observed in 24% of affected females in the largest cohort of NEXMIF-related disorders reported to date, but long-term adult outcomes remain poorly documented. Methods and Results: We report a 25-year-old Italian woman with drug-resistant Jeavons syndrome in which the combined approach of next-generation sequencing and chromosomal microarray analysis allowed us to identify, after a 13-year diagnostic odyssey, a de novo ~350 Kb microdeletion at Xq13.2q13.3 encompassing the entire NEXMIF coding region, with no other OMIM genes involved. To our knowledge, this is the first reported case of a patient harboring a deletion restricted to the entire coding sequence of the NEXMIF gene. The patient presented with moderate intellectual disability and seizure onset at age 10 years. Her epilepsy proved refractory to multiple antiseizure medications. Video-EEG/polygraphic monitoring at age 23 years confirmed epilepsy with eyelid myoclonia, demonstrating characteristic eyelid myoclonia with absences triggered by eye closure. Conclutions: This case provides a detailed clinical description of an adult patient useful for genetic counseling regarding adult outcomes and prognostic expectations. Furthermore, this study underscores the diagnostic value of chromosomal microarray analysis alongside next-generation sequencing in individuals with intellectual disability and drug-resistant epilepsy, in order to expedite the diagnostic pathway and enable timelier and more appropriate patient management. Full article
(This article belongs to the Special Issue Molecular Basis and Genetics of Neurodevelopmental Disorders)
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20 pages, 3510 KB  
Article
Nondestructive Detection of Eggshell Thickness Using Near-Infrared Spectroscopy Based on GBDT Feature Selection and an Improved CatBoost Algorithm
by Ziqing Li, Ying Ji, Changheng Zhao, Dehe Wang and Rongyan Zhou
Foods 2026, 15(8), 1286; https://doi.org/10.3390/foods15081286 - 8 Apr 2026
Viewed by 212
Abstract
Eggshell thickness is a critical indicator for evaluating egg breakage resistance and hatchability, yet traditional measurement methods remain destructive and inefficient. To address this, this study proposes a robust prediction approach by integrating Gradient Boosting Decision Tree (GBDT) feature optimization with an improved [...] Read more.
Eggshell thickness is a critical indicator for evaluating egg breakage resistance and hatchability, yet traditional measurement methods remain destructive and inefficient. To address this, this study proposes a robust prediction approach by integrating Gradient Boosting Decision Tree (GBDT) feature optimization with an improved CatBoost algorithm. First, a joint strategy of Standard Normal Variate (SNV) and Multiplicative Scatter Correction (MSC) was employed to eliminate spectral scattering noise and enhance organic matrix fingerprint information. Subsequently, GBDT was introduced for nonlinear feature evaluation to adaptively screen the top 50 wavelengths, effectively mitigating the “curse of dimensionality” and multicollinearity in full-spectrum data. A CatBoost regression model was then constructed using an Ordered Boosting mechanism, supported by a dual anti-overfitting strategy that merged 10-fold nested cross-validation with Bootstrap resampling. Experimental results demonstrate that this method significantly outperforms traditional algorithms in both prediction accuracy and generalization. The coefficients of determination (R2) for the calibration and prediction sets reached 0.930 and 0.918, respectively, with a root mean square error of prediction (RMSEP) of 0.008 mm. Residual analysis confirms that prediction errors follow a zero-mean Gaussian distribution, indicating that systematic bias was effectively eliminated. This research provides a reliable theoretical foundation and technical support for the intelligent grading of poultry egg quality. Full article
(This article belongs to the Section Food Analytical Methods)
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22 pages, 10859 KB  
Article
Multifractal Evolution Patterns of Microporous Structures with Coalification Degree
by Jiangang Ren, Bing Li, Xiaoming Wang, Fan Zhang, Chengtao Yang, Peiwen Jiang, Jianbao Liu, Yanwei Qu, Haonan Li and Zhimin Song
Fractal Fract. 2026, 10(4), 235; https://doi.org/10.3390/fractalfract10040235 - 1 Apr 2026
Viewed by 278
Abstract
The dominant pores governing methane adsorption in coal are micropores (pore size < 2 nm). Their spatial heterogeneity can be quantitatively characterized using multifractal theory; however, the evolution patterns and mechanisms of microporous structures across different coalification degrees remain unclear. This research selected [...] Read more.
The dominant pores governing methane adsorption in coal are micropores (pore size < 2 nm). Their spatial heterogeneity can be quantitatively characterized using multifractal theory; however, the evolution patterns and mechanisms of microporous structures across different coalification degrees remain unclear. This research selected a series of coal samples from different ranks and identified the coalification degree using the maximum vitrinite reflectance (R,max). By comprehensively employing low-temperature CO2 adsorption experiments and multifractal analysis, the evolution patterns of the microporous structures and their multifractal spectral parameters were systematically revealed, and the underlying control mechanisms were explored. Results indicate that micropore volume (PV) and specific surface area (SSA) first exhibit a decrease and then increase as R,max increases, with the trough occurring during the second coalification jump at R,max = 1.2–1.4%. The pore sizes exhibit bimodal distributions, with the primary peak occurring in the range of 0.45–0.65 nm and the secondary peak occurring in the range of 0.8–0.9 nm. All microporous structures possess pronounced multifractal characteristics. The generalized dimension spectrum width (ΔD) and singularity spectrum width (Δα) exhibit an increasing–decreasing–increasing trend with R,max, whereas the Hurst exponent (H) follows an inverted parabolic curve, first increases then decreases. This contrasts with the trends in PV and SSA, indicating that the evolution of pore-space heterogeneity and connectivity is independent of and lags the changes in micropore quantity. These patterns are governed by a structural phase transition within the coal macromolecular network. Marked by the second coalification jump, the microporous system shifts from a flexible degradation–polycondensation paradigm to a rigid ordering–construction paradigm. This transition drives the asynchronous, synergistic evolutions of pore quantity, spatial heterogeneity (ΔD and Δα), and topological connectivity (H). This research provides a theoretical basis for quantitatively evaluating pore heterogeneity in coal reservoirs. Full article
(This article belongs to the Section Engineering)
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22 pages, 8049 KB  
Article
Multi-Channel Vibration Signal Analysis for Flexible Bearing Fault Diagnosis of Industrial Robot Harmonic Drives
by Rongzhou Lin, Xiaohui Duan and Tongxin Gao
Sensors 2026, 26(7), 2134; https://doi.org/10.3390/s26072134 - 30 Mar 2026
Viewed by 373
Abstract
In industrial robots, harmonic drive flexible bearings are prone to faults, and fault diagnosis is essential for preventing unexpected downtime. However, vibration signals acquired from robot joints are often non-stationary and contaminated by strong multi-source interference, including motion-induced interference and vibrations induced by [...] Read more.
In industrial robots, harmonic drive flexible bearings are prone to faults, and fault diagnosis is essential for preventing unexpected downtime. However, vibration signals acquired from robot joints are often non-stationary and contaminated by strong multi-source interference, including motion-induced interference and vibrations induced by the deformation of flexible components. Such interference severely masks the subtle signatures of faults. To address this issue, this paper proposes a fault diagnosis framework that leverages multi-channel vibration signals to enhance fault-related features. First, angular resampling is applied to eliminate speed-induced non-stationarity. Second, envelope extraction is utilized to obtain demodulated signals suitable for independent component analysis (ICA). Subsequently, ICA is employed to extract fault-related components from the multi-channel signals. Finally, the fault-related independent component is identified and analyzed via envelope order spectrum analysis. Experimental validation on an industrial robot under both single-joint and multi-joint operating conditions demonstrates the effectiveness of the proposed framework. The method suppresses multi-source interference and achieves accurate fault diagnosis for flexible bearings under complex operating conditions, with quantitative validation confirming the diagnostic performance of the proposed framework. Full article
(This article belongs to the Section Fault Diagnosis & Sensors)
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16 pages, 8167 KB  
Article
Cascaded Polynomial and MLP Regression for High-Precision Geometric Calibration of Ultraviolet Single-Photon Imaging System
by Wanhong Yan, Lingping He, Chen Tao, Tianqi Ma, Zhenwei Han, Sibo Yu and Bo Chen
Photonics 2026, 13(4), 330; https://doi.org/10.3390/photonics13040330 - 28 Mar 2026
Viewed by 367
Abstract
To meet the requirements of quantitative elemental analysis in the ultraviolet (UV) spectrum, a UV single-photon imaging system was developed, integrating a digital micromirror device (DMD) and a single photon-counting imaging detector, enabling high sensitivity, high resolution, and a wide dynamic range. However, [...] Read more.
To meet the requirements of quantitative elemental analysis in the ultraviolet (UV) spectrum, a UV single-photon imaging system was developed, integrating a digital micromirror device (DMD) and a single photon-counting imaging detector, enabling high sensitivity, high resolution, and a wide dynamic range. However, intrinsic geometric distortion poses a significant challenge to accurate spectral calibration. A hybrid correction framework is proposed, cascading polynomial coarse correction with multilayer perceptron (MLP) fine regression, improving calibration accuracy. The method utilizes a full-field dot-array mask projected by the DMD to acquire distortion-reference image pairs. The polynomial model rapidly captures the dominant high-order distortion, while a lightweight MLP performs non-parametric fine regression of residual displacements, achieving a mean error of 0.84 pixels. This approach reduces the root mean square (RMS) error to 1.01 pixels, outperforming traditional direct linear transformation (5.35 pixels) and pure polynomial models (1.33 pixels), while the nonlinearity index decreases from 0.35° to 0.05°. In addition, the method demonstrates stable performance across multi-scale checkerboard patterns ranging from 128 to 280 pixels, with RMS errors remaining around the 1-pixel level. These results validate the high-precision distortion suppression and robust cross-scale performance of the proposed framework. By leveraging DMD-generated patterns for self-calibration, this method eliminates the need for external targets, offering a scalable solution for high-end spectrometer calibration. Full article
(This article belongs to the Section Lasers, Light Sources and Sensors)
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32 pages, 16696 KB  
Article
An Intelligent Framework for Crowdsource-Based Spectrum Misuse Detection in Shared-Spectrum Networks
by Debarun Das and Taieb Znati
Network 2026, 6(2), 19; https://doi.org/10.3390/network6020019 - 26 Mar 2026
Viewed by 239
Abstract
Dynamic Spectrum Access (DSA) has emerged as a viable solution to address spectrum scarcity in shared-spectrum networks. In response, the FCC established the Citizens Broadband Radio Service (CBRS) to manage and facilitate shared use of the federal and non-federal spectrum in a three-tiered [...] Read more.
Dynamic Spectrum Access (DSA) has emerged as a viable solution to address spectrum scarcity in shared-spectrum networks. In response, the FCC established the Citizens Broadband Radio Service (CBRS) to manage and facilitate shared use of the federal and non-federal spectrum in a three-tiered access and authorization framework. However, due to the open nature of spectrum access and the usually limited coverage of the monitoring infrastructure, enforcing access rights in a shared-spectrum network becomes a daunting challenge. In this paper, we stipulate the use of crowdsourcing as a viable approach to engaging volunteers in spectrum monitoring in order to enforce spectrum access rights robustly and reliably. The success of this approach, however, hinges strongly on ensuring that spectrum access enforcement is carried out by reliable and trustworthy volunteers within the monitored area. To this end, a hybrid spectrum monitoring framework is proposed, which relies on opportunistically recruiting volunteers to augment the otherwise limited infrastructure of trusted devices. Although a volunteer’s participation has the potential to enhance monitoring significantly, their mobility may become problematic in ensuring reliable coverage of the monitored spectrum area. To ensure continued monitoring, inspite of volunteer mobility, deep learning-based models are used to predict the likelihood that a volunteer will be available within the monitoring area. Three models, namely LSTM, GRU, and Transformer, are explored to assess their feasibility and viability to predict a volunteer’s availability likelihood over an extended time interval, in a given spectrum monitoring area. Recurrent Neural Networks (RNNs) such as GRU and LSTM are effective for tasks involving sequential data, where both spatial and temporal patterns matter, which is the focus of volunteer availability prediction in spectrum monitoring. Transformers, on the other hand, excel at handling long range dependencies and contextual understanding. Furthermore, their parallel processing capabilities allows faster training and inference compared to RNN-based models like GRU and LSTM. A simulation-based study is developed to assess the performance of these models, and carry out a comparative analysis of their ability to predict volunteers’ availability to monitor the spectrum reliably. To this end, a real-world trace dataset of volunteers’ location, collected over five years, is used. The simulation results show that the three models achieve high prediction accuracy of volunteers’ availability, ranging from 0.82 to 0.92. The results also show that a GRU-based model outperforms LSTM and Transformer-based models, in terms of accuracy, Root Mean Square Error (RMSE), geodesic distance, and execution time. Full article
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18 pages, 3193 KB  
Article
Synthesis, Antifungal Activity, 3D-QSAR, and Molecular Docking Study of Anethole-Based Thiazolinone-Hydrazone Compounds
by Yao Chen, Yu-Cheng Cui, You-Qiong Bi, Zhang-Li Guo, Xian-Li Ma, Wen-Gui Duan and Gui-Shan Lin
Molecules 2026, 31(7), 1078; https://doi.org/10.3390/molecules31071078 - 25 Mar 2026
Viewed by 323
Abstract
In order to find green fungicides derived from natural products, 22 unreported anethole-based thiazolinone-hydrazone compounds were designed and synthesized, and their structures were characterized by FT-IR, 1H NMR, 13C NMR, and HRMS. At a concentration of 50 mg/L, the preliminary antifungal [...] Read more.
In order to find green fungicides derived from natural products, 22 unreported anethole-based thiazolinone-hydrazone compounds were designed and synthesized, and their structures were characterized by FT-IR, 1H NMR, 13C NMR, and HRMS. At a concentration of 50 mg/L, the preliminary antifungal activity of the target compounds against eight plant pathogens was evaluated. The results showed that 5q (R = m-OH C6H4) exhibited the best inhibitory activity against most of the tested plant pathogenic fungi, demonstrating that this compound had certain broad-spectrum antifungal activity. In addition, a reasonable and effective 3D-QSAR model (r2 = 0.994, q2 = 0.529) was established using the comparative molecular field analysis (CoMFA) method to study the relationship between the structures of the target compounds and their antifungal activity against Physalospora piricola. Meanwhile, the results of electrostatic potential calculation of the compounds indicated that the electronic effect caused by different substituents on the benzene ring might be one of the factors affecting antifungal activity. In addition, frontier molecular orbital calculations implied that the anethole moiety and the thiazolinone-hydrazone-benzene structure in the target compounds might play an important role in antifungal activity. The potential binding mode between the target compound 5q (R = m-OH C6H4) and the homology-modeled succinic dehydrogenase was explored by molecular docking. Full article
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21 pages, 712 KB  
Article
Spectral Stability of Travelling Waves in a δ-Regularized Dissipative Sine-Gordon Equation
by Vassilios M. Rothos
Symmetry 2026, 18(3), 512; https://doi.org/10.3390/sym18030512 - 17 Mar 2026
Viewed by 176
Abstract
We analyze the spectral stability of travelling waves in a δ-regularized dissipative sine-Gordon equation modelling refined long Josephson junction dynamics. Linearization about a wave yields a singularly perturbed fourth-order spectral problem with intrinsic slow–fast spatial structure. Using an Evans-function formulation on a [...] Read more.
We analyze the spectral stability of travelling waves in a δ-regularized dissipative sine-Gordon equation modelling refined long Josephson junction dynamics. Linearization about a wave yields a singularly perturbed fourth-order spectral problem with intrinsic slow–fast spatial structure. Using an Evans-function formulation on a domain of consistent spatial splitting, we establish a local factorization separating slow and fast modes and prove that the δ-induced fast subsystem remains uniformly hyperbolic and does not generate an additional point spectrum near λ=0. Hence, the local point spectrum coincides with that of the classical dissipative sine-Gordon equation. Numerical computations of the essential spectrum and Evans winding numbers confirm the analysis and show that the higher-order terms enhance high-frequency damping without altering low-frequency spectral stability. Full article
(This article belongs to the Section Mathematics)
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25 pages, 8047 KB  
Article
On the Numerical Reliability of Lyapunov-Based Chaos Analysis in Optically Injected Semiconductor Lasers: A Phasor-Quadrature Comparison
by Gerardo Antonio Castañón Ávila, Ana Maria Sarmiento-Moncada, Alejandro Aragón-Zavala and Ivan Aldaya Garde
Appl. Sci. 2026, 16(6), 2835; https://doi.org/10.3390/app16062835 - 16 Mar 2026
Viewed by 292
Abstract
Lyapunov-exponent-based diagnostics are widely used to quantify deterministic chaos in optically injected semiconductor lasers (OISLs). In most numerical implementations, the optical field is represented either in phasor coordinates (A,ψ,N) or in Cartesian quadrature coordinates [...] Read more.
Lyapunov-exponent-based diagnostics are widely used to quantify deterministic chaos in optically injected semiconductor lasers (OISLs). In most numerical implementations, the optical field is represented either in phasor coordinates (A,ψ,N) or in Cartesian quadrature coordinates (X,Y,N). Although these representations are mathematically related through a smooth coordinate transformation away from vanishing field amplitude, their numerical realizations can exhibit markedly different robustness in variational calculations, directly impacting the reliability of Lyapunov exponent estimation and chaoticity maps. In this work, we present a systematic assessment of the numerical reliability of Lyapunov-based chaos analysis in master-slave optically injected semiconductor lasers using both phasor and quadrature formulations. The full Lyapunov spectrum was computed via a noise-free variational method that integrates the nonlinear dynamics together with the corresponding Jacobian equations using a fourth-order Runge-Kutta scheme combined with periodic QR orthonormalization. High-resolution Lyapunov maps were constructed in the injection strength-frequency detuning parameter space, and the consistency between both formulations was quantitatively evaluated. While both approaches reproduce the overall structure of chaotic and non-chaotic regions, the phasor formulation may generate spurious positive Lyapunov exponents in regimes where the optical field amplitude approaches low values. These discrepancies originate from singular terms proportional to 1/A and 1/A2 in the variational Jacobian of the phasor model, which can lead to numerical amplification and artificial chaotic signatures. The quadrature formulation avoids these singularities and provides numerically stable and physically consistent Lyapunov spectra across the explored parameter space. The results establish practical guidelines for robust chaos quantification in optically injected semiconductor lasers and highlight the importance of representation choice in variational Lyapunov analysis of nonlinear photonic systems. Full article
(This article belongs to the Special Issue Advances in Optical Communication and Photonic Integrated Devices)
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27 pages, 3308 KB  
Article
Exact Fractional Wave Solutions and Bifurcation Phenomena: An Analytical Exploration of (3 + 1)-D Extended Shallow Water Dynamics with β-Derivative Using MEDAM
by Wafaa B. Rabie, Taha Radwan and Hamdy M. Ahmed
Fractal Fract. 2026, 10(3), 190; https://doi.org/10.3390/fractalfract10030190 - 13 Mar 2026
Viewed by 343
Abstract
This study presents a comprehensive investigation of exact fractional wave solutions and bifurcation analysis for the (3 + 1)-dimensional extended shallow water wave (3D-eSWW) equation with β-derivative, which models nonlinear wave phenomena in fluid dynamics and coastal engineering. Leveraging the flexibility of [...] Read more.
This study presents a comprehensive investigation of exact fractional wave solutions and bifurcation analysis for the (3 + 1)-dimensional extended shallow water wave (3D-eSWW) equation with β-derivative, which models nonlinear wave phenomena in fluid dynamics and coastal engineering. Leveraging the flexibility of the fractional derivative, the model provides a more generalized and adaptable framework for describing shallow water wave propagation. The Modified Extended Direct Algebraic Method (MEDAM) is systematically employed to derive a broad spectrum of novel exact analytical solutions. These include the following: dark solitary waves, singular solitons, singular periodic waves, periodic solutions expressed via trigonometric and Jacobi elliptic functions, polynomial solutions, hyperbolic wave patterns, combined dark–singular structures, combined hyperbolic–linear waves, and exponential-type wave profiles. Each solution family is presented with explicit parameter constraints that ensure both mathematical consistency and physical relevance, thereby offering a robust classification of wave regimes under diverse conditions. A thorough bifurcation analysis is conducted on the reduced dynamical system to examine parametric dependence and stability transitions. Critical bifurcation thresholds are identified, and distinct solution branches are mapped in the parameter space spanned by wave numbers, nonlinear coefficients, external forcing, and the fractional order β. The analysis reveals how solution dynamics undergo qualitative transitions—such as the emergence of solitary waves from periodic patterns or the appearance of singular structures—driven by the interplay of nonlinearity, dispersion, and fractional-order effects. These insights are crucial for understanding wave stability, predictability, and the onset of extreme events in shallow water contexts. Graphical representations of selected solutions validate the analytical results and illustrate the influence of β on wave morphology, propagation, and stability. The simulations demonstrate that varying the fractional order can significantly alter wave profiles, highlighting the role of fractional calculus in capturing complex real-world behaviors. This work demonstrates the efficacy of the MEDAM technique in handling high-dimensional fractional nonlinear PDEs and provides a systematic framework for predicting and classifying wave regimes in real-world shallow water environments. The findings not only enrich the solution inventory of the 3D-eSWW equation but also advance the analytical toolkit for studying complex spatio-temporal dynamics in fractional mathematical physics and fluid mechanics. Ultimately, this research contributes to the development of more accurate models for coastal protection, tsunami forecasting, and marine engineering applications. Full article
(This article belongs to the Section General Mathematics, Analysis)
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16 pages, 3991 KB  
Article
Development of a Broad-Spectrum High Affinity Antibody for a Non-Targeted Early Warning and Verification Strategy of Organophosphorus Nerve Agents Exposure
by Yiling Liu, Jinjuan Xue, Fan Xia, Jia Chen, Jianfeng Wu, Shuxuan Cao, Wei You, Jinqiao Jiang, Xiaolei Zhang and Jianwei Xie
Analytica 2026, 7(1), 25; https://doi.org/10.3390/analytica7010025 - 13 Mar 2026
Viewed by 336
Abstract
Phosphonyl tyrosine is one of the main biomarkers to confirm exposure to highly lethal organophosphorus nerve agents (OPNAs) in vivo. However, a critical challenge remains unresolved: ionization suppression occurs during the analysis of phosphonyl tyrosine by high-resolution mass spectrometry (HRMS) or tandem mass [...] Read more.
Phosphonyl tyrosine is one of the main biomarkers to confirm exposure to highly lethal organophosphorus nerve agents (OPNAs) in vivo. However, a critical challenge remains unresolved: ionization suppression occurs during the analysis of phosphonyl tyrosine by high-resolution mass spectrometry (HRMS) or tandem mass spectrometry (MS/MS), which is induced by the high concentrations of free amino acids present in the digestion solution. In this study, based on the broad-spectrum immunomagnetic beads with high affinity antibodies, a non-targeted early warning and verification strategy was developed. Compared with the recommended operating procedures for analysis in the verification of chemical disarmament, the total analysis time was reduced from several hours to about 30 min. Moreover, the detection sensitivity was increased by nearly one order of magnitude, and the detection limit (LOD) was 0.01 ng/mL. Furthermore, the screening strategy can cover all OPNAs listed as 1A.01, 1A.02 and 1A.03 in Schedule 1 of the CWC. Therefore, we have developed a rapid, sensitive, and broad-spectrum approach to accurately screen for OPNAs exposure, while also offering a novel strategy and technical support for chemical defense and occupational health assessment. Full article
(This article belongs to the Section Chromatography)
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11 pages, 8363 KB  
Article
Ultrafast Optical Analysis and Control of Spectral Flatness in Cavity-Less Electro-Optic Combs
by Xin Chen, Hongyu Zhang, Meicheng Fu, Huan Chen, Yi Zhang, Yao Xu, Mengjun Zhu, Wenjun Yi, Qi Yu, Junli Qi, Qi Huang, Yubo Luo and Xiujian Li
Micromachines 2026, 17(3), 350; https://doi.org/10.3390/mi17030350 - 12 Mar 2026
Viewed by 341
Abstract
The cavity-less electro-optic combs (EOCs), recognized for exceptional tunability, stability and high power, are a crucial enabler for the fields such as optical communications, precision measurement and metrology, and microwave photonics. This work systematically investigates the fundamental physical factors that govern the spectral [...] Read more.
The cavity-less electro-optic combs (EOCs), recognized for exceptional tunability, stability and high power, are a crucial enabler for the fields such as optical communications, precision measurement and metrology, and microwave photonics. This work systematically investigates the fundamental physical factors that govern the spectral flatness via ultrafast measurements and modeling simulations. The ultrafast analysis results demonstrate that, the finite effective modulation extinction ratio of the electro-optic intensity modulators will result in generation of coherent spectral components with identical frequencies but varying phases and amplitudes in ultrashort temporal scale, finally lead to remarkable spectral interference and further intensity fluctuations across the combs spectrum. Furthermore, the established mathematical relationship between the spectral flatness and the modulation extinction ratio of the intensity modulators exhibits a nonlinear dependence up to the third order. Cascading intensity modulators has been exploited to mitigate the spectral interference and improve the modulation extinction ratio, which has been verified by using home-made high sensitive autocorrelator and frequency-resolved optical gating (FROG), and finely spectral flatness of 0.54 dB among 11 lines has been achieved, which recognized for the first time that modulation extinction ratio related spectral interference phenomenon play a subtle role in EOCs generation. Furthermore, photonic analog-to-digital converters (PADCs) have been investigated and an obvious enhancement in signal-to-noise-and-distortion (SINAD) is achieved, These findings will provide crucial theoretical and experimental support for optimizing EOCs performance, and advance the development and application. Full article
(This article belongs to the Special Issue Advanced Optoelectronic Materials/Devices and Their Applications)
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27 pages, 4748 KB  
Article
A Filter Method for Dynamic Monitoring Data of Masonry Partition Walls in Subway Stations Based on a Butterworth Filter
by Mingmin Wang, Zhibo Bao, Bolun Shi and Wei Zhou
Buildings 2026, 16(5), 1057; https://doi.org/10.3390/buildings16051057 - 6 Mar 2026
Viewed by 317
Abstract
Under the combined effects of vibrations from train operations and wind loads, the dynamic response monitoring data of masonry partition walls in subway stations are often contaminated with high-frequency noise, which hinders the accurate identification of the structure’s true dynamic characteristics. To tackle [...] Read more.
Under the combined effects of vibrations from train operations and wind loads, the dynamic response monitoring data of masonry partition walls in subway stations are often contaminated with high-frequency noise, which hinders the accurate identification of the structure’s true dynamic characteristics. To tackle this problem, this paper proposes employing a Butterworth low-pass filter to process the on-site monitoring data. The paper initially elaborates on the monitoring theory grounded in the pulsation method, followed by a detailed explanation of the rationale for selecting the Butterworth filter, as well as data processing techniques such as Fast Fourier Transform (FFT) and self-power spectrum analysis. By incorporating a field monitoring case from a subway station in Guangzhou, the paper compares and analyzes the acceleration time-history curves before and after filtering. Additionally, finite element analysis is performed to assess the mechanical response of the masonry wall under wind loads, train-induced vibrations, and their combined effects. The results demonstrate that after applying a 4th-order Butterworth low-pass filter with a 46 Hz cutoff frequency, the high-frequency noise in the data is effectively suppressed, thereby accentuating the main trend and low-frequency vibration characteristics of the signal. This provides a reliable data foundation for subsequent precise analysis of the dynamic response and fatigue performance of the masonry walls. Full article
(This article belongs to the Special Issue Advanced Structural Performance of Concrete Structures)
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17 pages, 2977 KB  
Article
Strategically Designed Coaxial Electrospun Nanofibers of Polylactic Acid/Glycerol Monolaurate Hydroxypropyl-γ-Cyclodextrin Inclusion Compound with Sustained Release for Active Food Packaging
by Yan Zhang, Siyu Zhu, Guang Yang, Jiahui Duan, Yanyan Liu, Shuang Gao and Fengrui Li
Foods 2026, 15(5), 872; https://doi.org/10.3390/foods15050872 - 4 Mar 2026
Viewed by 392
Abstract
Post-harvest deterioration in strawberries is an urgent and critical issue that requires significant attention. Glycerol monolaurate (GML), a broad-spectrum food-grade antimicrobial agent, faces limited applicability due to its poor water solubility. In this study, a confined encapsulation strategy was employed to encapsulate GML [...] Read more.
Post-harvest deterioration in strawberries is an urgent and critical issue that requires significant attention. Glycerol monolaurate (GML), a broad-spectrum food-grade antimicrobial agent, faces limited applicability due to its poor water solubility. In this study, a confined encapsulation strategy was employed to encapsulate GML within hydroxypropyl-γ-cyclodextrin (HPγCD), which improved the physicochemical properties of GML and enhanced its stability in the environment. The fiber morphology was observed through scanning electron microscopy (SEM) and transmission electron microscopy (TEM), confirming the presence of a uniform, non-nodular core–shell structure. The Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) validated the successful encapsulation of GML within the cavity of HPγCD. Thermogravimetric analysis (TGA) demonstrated that the thermal stability of the core–shell system was significantly improved. In vitro release followed first-order kinetics (R2 = 0.9842), with 79.5% of GML released over 68 h. The DPPH and ABTS assays demonstrated that PLA/GML-HPγCD NF exhibited sustained radical scavenging activity (p < 0.05, ANOVA). Compared to GML-HPγCD NF, PLA/GML-HPγCD NF exhibited prolonged antibacterial activity against Escherichia coli and superior antifungal efficacy in strawberry preservation. Meanwhile, PLA/GML-HPγCD NF significantly reduced lesion diameter and weight loss while maintaining hardness, total soluble solids, and vitamin C content over 8 days of storage. In conclusion, these characteristics highlighted the potential of P/G-HPγCD NF as a promising active packaging material for extending the shelf life of perishable fruits. Full article
(This article belongs to the Special Issue Application of Plant Natural Products in Food Preservation)
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24 pages, 3929 KB  
Article
A Dual Quantum Dot Fluorescent Probe for Time-Resolved Chemometric Detection of Chloramphenicolin Pharmaceuticals
by Rafael C. Castro, Ricardo N. M. J. Páscoa, João L. M. Santos and David S. M. Ribeiro
Nanomaterials 2026, 16(5), 322; https://doi.org/10.3390/nano16050322 - 4 Mar 2026
Viewed by 419
Abstract
Dual-emission photoluminescence (PL) nanoprobes provide improved analytical performance to develop a reliable and sensitive sensing platform for quantifying chloramphenicol in pharmaceutical samples, thereby ensuring therapeutic efficacy and patient safety. In this work, a dual-emission PL sensing platform combining carbon dots (CDs) and AgInS [...] Read more.
Dual-emission photoluminescence (PL) nanoprobes provide improved analytical performance to develop a reliable and sensitive sensing platform for quantifying chloramphenicol in pharmaceutical samples, thereby ensuring therapeutic efficacy and patient safety. In this work, a dual-emission PL sensing platform combining carbon dots (CDs) and AgInS2 quantum dots (QDs) capped with mercaptopropionic acid (MPA) was developed for the quantitative determination of chloramphenicol, resorting to chemometric methods for data analysis. CDs, CdTe QDs, and AgInS2 QDs were synthesized and individually evaluated considering their photostability, PL response and kinetics of their interaction with the antibiotic. After this, two dual-emission probes, CDs/MPA-CdTe and CDs/MPA-AgInS2, were prepared and assessed based on the complementarity of their individual emission features. The obtained kinetic PL dataset was processed using unfolded partial least squares (U-PLS) in order to explore the multidimensional information of the dual-emission systems and to evaluate the performance of both sensing platforms. CDs/MPA-AgInS2 probe was demonstrated to be the most efficient sensing platform due to its better compromise between sensitivity and photostability, as well as its cadmium-free composition, allowing the implementation of a more environmentally friendly analytical methodology. The optimization of the U-PLS models involved the assessment of the kinetic acquisition time and different spectral regions. The results showed that reliable, sensitive and efficient quantification could be achieved within the first 5 min of interaction and using the full emission spectrum of the sensing probe. Additionally, different interaction mechanisms were observed for each nanomaterial in the combined probe, being static for the CDs/chloramphenicol interaction and dynamic for MPA-AgInS2/chloramphenicol interaction, which supports the synergetic behavior of the combined probe. The proposed methodology was effectively applied to commercial pharmaceutical formulations, yielding accurate results with good figures of merit. Therefore, this approach can be used as a relevant alternative to existing methodologies for a rapid, robust, and environmentally friendly method for chloramphenicol quantification. Full article
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