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12 pages, 1303 KB  
Article
Sinus Rhythm Propagation and Low-Voltage Bridge in Koch’s Triangle: How They Relate in Cryoablation of Atrioventricular Nodal Reentry Tachycardia in Children
by Francesco Flore, Michele Lioncino, Pietro Paolo Tamborrino, Ilaria Cazzoli, Alberto Ferraro, Vincenzo Pazzano, Daniele Garozzo, Cristina Raimondo, Massimo Stefano Silvetti and Fabrizio Drago
J. Clin. Med. 2026, 15(8), 3058; https://doi.org/10.3390/jcm15083058 - 16 Apr 2026
Abstract
Background/Objectives: Transcatheter ablation assisted by three-dimensional (3D) electroanatomical mapping (EAM) is the elective treatment for atrioventricular nodal reentrant tachycardia (AVNRT) in children and adolescents. In this population of patients, the most frequently employed EAM strategies are the low-voltage bridge (LVB) strategy and [...] Read more.
Background/Objectives: Transcatheter ablation assisted by three-dimensional (3D) electroanatomical mapping (EAM) is the elective treatment for atrioventricular nodal reentrant tachycardia (AVNRT) in children and adolescents. In this population of patients, the most frequently employed EAM strategies are the low-voltage bridge (LVB) strategy and sinus rhythm propagation mapping (SRPM). However, the exact pathophysiology and anatomy of the AVNRT reentrant circuits are still poorly understood. The aim of this study was to investigate the relationship between SRPM and LVB and to shed light on nodal physiology in children and adolescents affected by AVNRT. Methods: We retrospectively collected data on pediatric patients who underwent cryoablation for AVNRT assisted by high-density 3D EAM by using the LVB strategy; maps were reviewed by two independent electrophysiologists and the SRPM was described. SRPM was defined as typical when only one collision area was identified and atypical whenever either no or ≥ two collision areas were localized. Results: Twenty-eight consecutive patients (11.3 ± 3.3 years) were enrolled. All procedures were acutely successful. Overall, atypical SRPM was present in 10 patients (35.7%), and it did not correlate with the presence of multiple SPs or electrophysiological data. Moreover, we observed an imperfect concordance between SRPM and LVB (only in 10/18 patients). When SRPM and LVB were assessed in different locations, the LVB identified the effective cryoablation site in more cases than SRPM (4/8 vs. 1/8). Lastly, in cases of double collision, one collision area co-localized with the LVB and the effective cryoablation spot, whereas the other was located superiorly, closer to the His bundle. Conclusions: Atypical sinus rhythm propagation in the Koch’s triangle is a frequent finding in pediatric AVNRT patients. In this series, LVB showed closer concordance with the successful cryolesion site than retrospectively reconstructed SRPM. Full article
(This article belongs to the Special Issue Clinical Management of Pediatric Heart Diseases)
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20 pages, 4882 KB  
Article
Repellent and Lethal Effects of Different Wavelengths of Light-Emitting Diodes (LEDs) Against Tetranychus urticae
by Fatih Dağlı, Nurdan Topakcı, Nuri Çağlayan and Davut Karayel
Crops 2026, 6(2), 39; https://doi.org/10.3390/crops6020039 - 1 Apr 2026
Viewed by 280
Abstract
The two-spotted spider mite, Tetranychus urticae Koch, is a major agricultural pest that causes economic losses in the cultivation of most crops worldwide. Pesticide resistance and the phase-out of many active pesticidal substances have accelerated research into alternative methods for pest management. The [...] Read more.
The two-spotted spider mite, Tetranychus urticae Koch, is a major agricultural pest that causes economic losses in the cultivation of most crops worldwide. Pesticide resistance and the phase-out of many active pesticidal substances have accelerated research into alternative methods for pest management. The effects of light-emitting diodes (LEDs) on plants, as well as their potential use in pest management, have attracted the attention of researchers for the last 25 years. In this study, the repellent effects of UV-A, blue, and red LEDs on T. urticae were investigated using choice tests in laboratory conditions. The lethal effect of red LED light on adult individuals was determined by a no-choice test. Importantly, red LED caused 67.0 ± 4.5% (mean ± SE) mortality in adults in the no-choice test. Second, the UV-A LED clearly had a strong repellent effect on T. urticae in the choice tests. In the “UV-A vs. white LED” and “UV-A vs. darkness” choice tests, the egg-laying percentage in the UV-A part remained below 0.55%. Furthermore, UV-A also had a significant repellent effect on T. urticae larvae. In the choice tests, the larval ratio in the UV-A part was less than 5%. The results of laboratory experiments indicated that red and UV-A LEDs have significant lethal and repellent effects on T. urticae. Comprehensive investigations should be performed in greenhouses using different strategies to optimize how these potential effects can be used in pest management. Full article
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24 pages, 20988 KB  
Article
Monitoring of Oyster Reef Spatial Distribution with Thermal Infrared Band Data
by Xirui Xu, Fei Wang, Weimin Quan, Ruiliang Fan, Wei Fan and Sanling Yuan
Fishes 2026, 11(4), 209; https://doi.org/10.3390/fishes11040209 - 1 Apr 2026
Viewed by 317
Abstract
The spatial distribution of oyster reefs is an important indicator for assessing environmental changes in nearshore fishery habitats. However, due to tidal fluctuations, images of oyster reef distribution acquired under low-light conditions such as early morning or evening often exhibit common issues such [...] Read more.
The spatial distribution of oyster reefs is an important indicator for assessing environmental changes in nearshore fishery habitats. However, due to tidal fluctuations, images of oyster reef distribution acquired under low-light conditions such as early morning or evening often exhibit common issues such as bright spots and shadows. Thermal infrared (TIR) images, which are unaffected by external lighting conditions, can effectively address this problem. Aerial imaging of Liya Mountain, Haimen, Jiangsu Province, China, was conducted in this study. Based on unmanned aerial vehicles (UAVs) imagery acquired in 2025 using multispectral and TIR sensors, the total oyster reef area was estimated to be 6.61 ha. When compared with the oyster reef distribution derived from visible light aerial imagery collected in 2023 under favorable environmental conditions, this represents a decrease of 0.36 ha (5.4%), with the largest individual reef measuring 3388.17 m2. To demonstrate the improvement in extraction accuracy achieved by integrating TIR data with multispectral imagery, the research team compared the extraction accuracy for oyster reefs of different sizes: a 1.91% improvement was observed for small reefs, a 9.02% improvement for middle reefs, and an 18.98% improvement for large reefs. Experimentally, the emissivity of oyster reefs was determined to be 0.982 ± 0.002 using an isothermal method in the laboratory. The emissivity derived from in situ measurements showed similar values, supporting the reliability of the laboratory result and providing a crucial parameter for the inversion of reef surface temperature. Experimental results demonstrate that the TIR band can effectively enhance the spatial accuracy of oyster reef measurements under low-light conditions. Full article
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35 pages, 14172 KB  
Article
A Multimodal Time-Frequency Fusion Architecture for Fault Diagnosis in Rotating Machinery
by Hui Wang, Congming Wu, Yong Jiang, Yanqing Ouyang, Chongguang Ren, Xianqiong Tang and Wei Zhou
Appl. Sci. 2026, 16(7), 3269; https://doi.org/10.3390/app16073269 - 27 Mar 2026
Viewed by 361
Abstract
Accurate fault diagnosis of rotating machinery in complex industrial environments demands an optimal trade-off between feature representation capability and computational efficiency. Existing single-modality models relying solely on 1D time-series signals or heavy 2D time-frequency images often fail to simultaneously capture high-frequency transient impacts [...] Read more.
Accurate fault diagnosis of rotating machinery in complex industrial environments demands an optimal trade-off between feature representation capability and computational efficiency. Existing single-modality models relying solely on 1D time-series signals or heavy 2D time-frequency images often fail to simultaneously capture high-frequency transient impacts and long-range degradation trends. CLiST (Complementary Lightweight Spatiotemporal Network), a novel lightweight multimodal framework driven by time-frequency fusion, was proposed to overcome this limitation. The architecture of CLiST employs a synergistic dual-stream design: a LightTS module efficiently extracts global operational trends from 1D vibration signals with linear complexity, while a structurally pruned LiteSwin integrated with Triplet Attention captures local high-frequency textures from 2D continuous wavelet transform (CWT) images. This mechanism establishes explicit cross-dimensional dependencies, effectively eliminating feature blind spots without excessive computational overhead. The experimental results show that CLiST not only achieves perfect accuracy on the fundamental CWRU benchmark but also exhibits exceptional spatial generalization when independently evaluated on non-dominant sensor axes of the XJTUGearbox dataset. Furthermore, validation on the real-world dataset (Guangzhou port) proves that the framework has excellent robustness to the attenuation of the signal transmission path and reduces the performance fluctuation between remote measurement points. Ultimately, CLiST delivers highly reliable AI-driven image and signal-processing solutions for vibration monitoring in industrial equipment. Full article
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22 pages, 7274 KB  
Article
An Intelligent Evaluation Method for Sweet Spots in Deep-Marine Shale Reservoirs Based on Lithofacies Control and Multi-Parameter Driving
by Yi Liu, Jin Wu, Boning Zhang, Chengyong Li, Dongxu Zhang, Tong Wang, Chen Yang, Yi Luo, Ye Gu, Li Zhang, Jing Yang and Kai Tong
Processes 2026, 14(6), 1007; https://doi.org/10.3390/pr14061007 - 21 Mar 2026
Viewed by 372
Abstract
Deep marine shale reservoirs are controlled by multi-factor coupling effects, and the genetic mechanism of “sweet spots” exhibits strong complexity, leading to prominent difficulties in quantitative prediction and precise evaluation of sweet spots. Aiming at the problems of an unclear lithofacies-controlled sweet spot [...] Read more.
Deep marine shale reservoirs are controlled by multi-factor coupling effects, and the genetic mechanism of “sweet spots” exhibits strong complexity, leading to prominent difficulties in quantitative prediction and precise evaluation of sweet spots. Aiming at the problems of an unclear lithofacies-controlled sweet spot evolution law and insufficient accuracy of multi-parameter quantitative evaluation in traditional evaluation methods, this paper takes the Wufeng Formation and Long1 member of the Longmaxi Formation in the LZ block, Southern Sichuan, as the research object. Innovatively integrating machine learning (ML), grey correlation analysis (GRA), and three-dimensiona (3D) geological modeling technologies, a refined prediction model for reservoir sweet spot evaluation indicators under lithofacies constraint conditions is established, and a multi-parameter fusion quantitative evaluation method for deep marine shale gas sweet spots with high prediction accuracy is proposed. The results demonstrate that the LightGBM-based prediction model for sweet spot evaluation indicators achieved excellent performance. Based on a total of 380 preprocessed samples divided into training and test sets in a 7:3 ratio, the coefficient of determination (R2) of the model exceeded 0.9 in both the test and validation datasets. The “sweetness index”, a comprehensive evaluation index of reservoir sweet spots constructed via GRA-based multi-factor fusion, shows a correlation coefficient of 0.91 with respect to actual gas well production, presenting a high fitting degree. The 3D sweet spot geological model reveals that Class I sweet spots are mainly developed in the 1st to 3rd sub-layers of the Long1 member, while Class II sweet spots are distributed in the 5th and 6th sub-layers, which is highly consistent with the actual development law of the gas field. This study breaks through the limitations of single evaluation methods and weak lithofacies control consideration in traditional sweet spot evaluation and forms a set of innovative technical process integrating “precision prediction—multi-factor fusion—3D characterization”. It provides a new technical approach for efficient and accurate evaluation of deep marine shale reservoir sweet spots and has important guiding significance for the efficient development of shale gas. Full article
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15 pages, 2181 KB  
Article
A Flexible and Thermally Uniform TiO2/Ag/SiO2 Transparent Heater for Skin-Integrated Applications
by Jaejeong Jo, Geonwoo Kang, Chankyoung Lee, Tran Thi Bao Vo and Dooho Choi
J. Funct. Biomater. 2026, 17(3), 151; https://doi.org/10.3390/jfb17030151 - 18 Mar 2026
Viewed by 644
Abstract
Transparent heaters intended for skin-contacting applications must simultaneously satisfy optical transparency, mechanical compliance, thermal uniformity, and operational safety under biologically relevant temperature ranges. Here, we evaluate the applicability of a TiO2/Ag/SiO2 (TAS) dielectric–metal–dielectric transparent heater as a functional biomaterial platform [...] Read more.
Transparent heaters intended for skin-contacting applications must simultaneously satisfy optical transparency, mechanical compliance, thermal uniformity, and operational safety under biologically relevant temperature ranges. Here, we evaluate the applicability of a TiO2/Ag/SiO2 (TAS) dielectric–metal–dielectric transparent heater as a functional biomaterial platform for wearable and skin-integrated thermal systems. By systematically optimizing each layer thickness of the TAS structure, the heater achieves high visible-light transmittance (average of 86.6%) together with low sheet resistance on the order of 7.7 Ω/sq for low-voltage operation. The TAS heater demonstrates rapid and reproducible Joule-heating behavior, showing fast thermal response with short thermal time constants and spatially homogeneous temperature distributions without localized hot spots. Stable electrothermal performance is maintained under repeated on/off cycling and during cyclic mechanical bending down to small radii, confirming excellent mechanical stability under repeated bending relevant to wearable applications. Importantly, direct on-skin evaluations conducted by attaching the device to a human elbow reveal conformal contact, uniform heating at therapeutically relevant temperatures (50–70 °C), and stable operation under dynamic bending and extension. The absence of thermal inhomogeneity during motion highlights the intrinsic stability of the TAS architecture for skin-interfaced use. Given the high optical visibility, mechanical compliance, thermal uniformity, and electrothermal stability, the proposed TAS architecture represents a promising functional biomaterial platform for wearable thermotherapy, skin-mounted healthcare devices, and human-interactive thermal systems operating under continuous mechanical deformation and direct skin contact. Full article
(This article belongs to the Special Issue Advanced Materials and Devices for Medical Interventions)
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18 pages, 5263 KB  
Article
TSNP-Ink on PDMS: A Flexible SERS Substrate for Damage-Free Agricultural Pesticide Detection
by Apinya Ketkong, Kheamrutai Thamaphat, Thana Sutthibutpong, Noppadon Nuntawong and Fueangfakan Chutrakulwong
Chemosensors 2026, 14(3), 72; https://doi.org/10.3390/chemosensors14030072 - 18 Mar 2026
Cited by 1 | Viewed by 504
Abstract
Sensitive and on-site detection of pesticide residues remains a critical challenge for food safety, particularly in developing regions where rapid screening tools are urgently needed. Herein, we report a flexible surface-enhanced Raman scattering (SERS) platform based on triangular silver nanoplates (TSNPs) integrated onto [...] Read more.
Sensitive and on-site detection of pesticide residues remains a critical challenge for food safety, particularly in developing regions where rapid screening tools are urgently needed. Herein, we report a flexible surface-enhanced Raman scattering (SERS) platform based on triangular silver nanoplates (TSNPs) integrated onto a polydimethylsiloxane (PDMS) substrate, enabling sensitive and conformal detection of paraquat residues on agricultural surfaces. TSNPs were synthesized via a seed-mediated photochemical growth method and formulated into a TSNP ink, which was directly deposited onto oxygen-plasma-treated and thiol-functionalized PDMS substrates. Owing to the highly anisotropic geometry and sharp edges of TSNPs, the flexible SERS substrate exhibits strong localized surface plasmon resonance (LSPR) enhancement and mechanically stable electromagnetic hot spots. Systematic optimization of TSNP optical absorbance revealed that uniform nanoplate distribution and optimal hotspot density were achieved at an absorbance of 2.0. The SERS performance was evaluated using rhodamine 6G under front-side and back-side illumination configurations, demonstrating good signal reproducibility and a detection limit of approximately 10−5 M. Notably, back-side illumination through the PDMS layer provided superior SERS responses due to improved optical transmission and light–matter interaction. The practical applicability was further demonstrated through back-side SERS detection of paraquat on aluminum foil as a model surface, achieving a lowest detectable concentration of 5 × 10−6 M, followed by damage-free detection on Chinese pear peels. This work highlights a reliable and nondestructive flexible SERS platform for on-site pesticide residue monitoring. Full article
(This article belongs to the Special Issue Spectroscopic Techniques for Chemical Analysis, 2nd Edition)
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20 pages, 21808 KB  
Article
Long-Wave Infrared Multispectral Imager for Lunar Remote Sensing: Optical Design and Performance Evaluation
by Haoyang Hu, Jianan Xie, Shiyi Qian, Liyin Yuan and Zhiping He
Photonics 2026, 13(3), 282; https://doi.org/10.3390/photonics13030282 - 15 Mar 2026
Viewed by 454
Abstract
High-resolution long-wave infrared imaging is critical for lunar mineralogy. However, it must balance a large FOV, a small F-number, chromatic aberration correction, optical efficiency, and system compactness. We introduce a push-broom multispectral imager employing a collaborative integrated filter array and an off-axis two-mirror [...] Read more.
High-resolution long-wave infrared imaging is critical for lunar mineralogy. However, it must balance a large FOV, a small F-number, chromatic aberration correction, optical efficiency, and system compactness. We introduce a push-broom multispectral imager employing a collaborative integrated filter array and an off-axis two-mirror Gregorian telescope. The system, utilizing an uncooled Vanadium Oxide detector, has an F-number of 1.0, an IFOV of 0.04943 mrad, and a 2.90° × 2.83° FOV that covers eight bands ranging between 7.38 and 14.3 μm. Optical simulation confirms that the modulation transfer function exceeds 0.25 at the Nyquist frequency of 42 lp/mm, with a maximum RMS spot radius of less than 12 μm. The system has remarkable versatility within an operating temperature range of 0 °C to 40 °C. Thermal background radiation analysis, stray light analysis, and detection sensitivity were conducted, which indicated that the system has good compliance with indicators and engineering feasibility. This high-throughput optical design meets the rigorous criteria for lunar remote sensing and provides a reliable device for site evaluation in future manned lunar missions. Full article
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20 pages, 7575 KB  
Article
Studies on Pathogen Identification, Biological Characteristics and Fungicide Sensitivity of Impatiens hawkeri Leaf Spot Disease
by Mengyao Wang, Ziyue Zhang, Yajiao Sun, Huali Li, Jian Liu, Shuwen Liu, Yunqiang Ma and Junjia Lu
J. Fungi 2026, 12(3), 210; https://doi.org/10.3390/jof12030210 - 14 Mar 2026
Viewed by 566
Abstract
Impatiens hawkeri W. Bull (I. hawkeri) is popular among consumers due to its diverse flower colors and year-round blooming. However, changes in ecological conditions, cultivation methods, and planting scale have led to increased disease incidence and diversity, particularly the widespread and [...] Read more.
Impatiens hawkeri W. Bull (I. hawkeri) is popular among consumers due to its diverse flower colors and year-round blooming. However, changes in ecological conditions, cultivation methods, and planting scale have led to increased disease incidence and diversity, particularly the widespread and destructive leaf spot disease. Currently, studies addressing the pathogen species and its biological characteristics remain limited. In this study, a highly pathogenic strain (IH-4) was selected from previously isolated fungi associated with leaf spot in I. hawkeri. Its taxonomic status was confirmed using upright fluorescence microscope analysis, internal transcribed spacer (ITS)/large subunit (LSU)/RNA polymerase II second largest subunit (rpb2)/β-tubulin (tub2) rRNA gene sequencing, and phylogenetic tree construction. Additionally, the biological characteristics of the pathogen and its sensitivity to 8 chemical fungicides were assessed. Strain IH-4 was identified as Ectophoma multirostrata (E. multirostrata) through combined morphological and molecular approaches. Optimal growth conditions included a temperature of 25 °C, a pH of 7, Potato Dextrose Agar (PDA) medium, fructose as the optimal carbon source, and urea as the optimal nitrogen source, with the fastest growth observed under a semi-light photoperiod (12 h light/12 h dark). Fungicide sensitivity assays indicated that 25% azoxystrobin exhibited the lowest half-maximal effective concentration (EC50, 0.0724 μg/mL) and the steepest virulence regression slope (1.7), demonstrating the strongest inhibitory activity and highest sensitivity. Microscopic observations revealed that IH-4 hyphae penetrate I. hawkeri leaf tissues via stomata, colonize internally, and consequently cause host damage. This study provides a theoretical foundation for the timely and effective management of leaf spot disease in I. hawkeri. Full article
(This article belongs to the Section Fungal Genomics, Genetics and Molecular Biology)
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18 pages, 4523 KB  
Article
Laser-Induced Degradation of Bi2Se3 THz Emitters Revealed by Raman Spectroscopy
by Roman Adam, Martin Mikulics, Daniel E. Bürgler, Kiryl A. Niherysh, Alexei Kalaboukhov, Sarah F. Heidtfeld, Ivan Komissarov, Roman Sobolewski, Claus M. Schneider, Joachim Mayer and Hilde H. Hardtdegen
Photonics 2026, 13(3), 278; https://doi.org/10.3390/photonics13030278 - 14 Mar 2026
Viewed by 491
Abstract
We present an investigation of the thermal damage threshold of passivated Bi2Se3 films upon laser illumination, with a focus on their employment in terahertz (THz) spectroscopic applications. Passivation was achieved by depositing a thin 3 nm Al capping layer which, [...] Read more.
We present an investigation of the thermal damage threshold of passivated Bi2Se3 films upon laser illumination, with a focus on their employment in terahertz (THz) spectroscopic applications. Passivation was achieved by depositing a thin 3 nm Al capping layer which, exposed to the ambient, forms a natural oxide. In THz transient emission experiments, the samples were exposed to a train of 100 fs wide laser pulses with 800 nm wavelength at 78 MHz repetition rate and peak power density up to 295 mW/µm2. For the sake of comparison, the films were also exposed to continuous wave laser light with a wavelength of 532 nm in the average optical power density range from 5 × 10−2 mW/µm2 to 50 mW/µm2. In both cases, changes in film appearance, detected by optical microscopy, or even film removal in a small area close to the center of the illuminated spot could be induced. Raman spectroscopy provided evidence that the crystalline phase of Bi2Se3 films is present in areas that have been exposed but not damaged. Conversely, in the film region illuminated with the highest peak power density no Raman signal was detected in the range under investigation which we ascribe to material removal. At the perimeter of this ablated area, we observed a dominant Raman mode at approximately 255 cm−1 that we can attribute to selenium and indicates partial Bi2Se3 decomposition. In contrast, we observed Raman spectra corresponding to as-deposited Bi2Se3 only a few micrometers away from the laser-damaged area. Hence, the observed THz radiation originates from this illuminated but undamaged region. This detailed knowledge is expected to serve as a guide for designing the emitter’s thermal management and choosing laser parameters for optimal operation. Full article
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13 pages, 6402 KB  
Article
Random-Induced High-Contrast Subwavelength Nondiffracting Structured Light
by Guangsen Guo, Junhui Jia, Xiaoshan Zhang, Junjie Chen, Shikuan Mai, Wenjia Wang, Haolin Lin, Yanwen Hu, Zhen Li and Shenhe Fu
Photonics 2026, 13(3), 274; https://doi.org/10.3390/photonics13030274 - 13 Mar 2026
Viewed by 365
Abstract
Nondiffracting structured light has attracted considerable attention owing to broad applications in both the classical and quantum optics. Despite extensive research, existing generation approaches suffer from a contradiction between the subwavelength focal spot size and the strong side lobes, leading to a low-contrast [...] Read more.
Nondiffracting structured light has attracted considerable attention owing to broad applications in both the classical and quantum optics. Despite extensive research, existing generation approaches suffer from a contradiction between the subwavelength focal spot size and the strong side lobes, leading to a low-contrast localized light field in the far field. Here, we theoretically report a distinct technique for the generation of high-contrast nondiffracting structured light with its feature size reaching a subwavelength scale. The presented technique relies on a randomly perturbed sharp-edge aperture, which comprises a basic circular obstacle for exciting the in-phase high-spatial-frequency diffractive waves and randomized slit motifs for realizing destructive interference among the zero-order diffractive components, emerging from the sharp-edge diffraction. With this framework, we obtain a continuous high-contrast light needle, both for the zero-order light mode and the higher-order light with topological structure. In both cases, the resultant light fields preserve their subwavelength intensity profiles along propagation distance. This operating strategy provides an effective manner for structured light generation in the subwavelength scale, offering opportunities for advanced applications such as super-resolution imaging and nano-scale light–matter interaction. Full article
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19 pages, 3294 KB  
Article
UAV-Based Oil Leakage Spot Detection Under Complex Illumination via a Collaborative Low-Light Enhancement and Detection Framework
by Yunsheng Ha, Ling Zhao and Huili Zhang
Sensors 2026, 26(6), 1819; https://doi.org/10.3390/s26061819 - 13 Mar 2026
Viewed by 286
Abstract
Accurate detection of oil leakage spots is essential for oilfield safety and environmental protection. However, UAV-based inspection in onshore oilfields often suffers from complex illumination conditions, such as low light, backlighting, and mixed shadows, which simultaneously degrade image visibility and obscure leakage-sensitive features, [...] Read more.
Accurate detection of oil leakage spots is essential for oilfield safety and environmental protection. However, UAV-based inspection in onshore oilfields often suffers from complex illumination conditions, such as low light, backlighting, and mixed shadows, which simultaneously degrade image visibility and obscure leakage-sensitive features, thereby causing missed detection of minute and weak-texture oil leakage targets. Unlike generic low-light enhancement or object detection tasks, the core challenge of onshore UAV oil leakage inspection lies in preserving leakage-oriented fine cues during enhancement while improving the detector’s ability to distinguish leakage targets from highly confusing oilfield backgrounds. To address this task-specific challenge, we propose a collaborative low-light enhancement and detection framework that jointly optimizes leakage-detail-preserving enhancement and multi-scale interference-suppressed detection. Specifically, an improved Retinex-based enhancement network is designed by integrating multi-scale feature aggregation, NAFNet-based denoising, and a CBAM attention mechanism to enhance brightness while preserving leakage details. The enhanced images are then fed into an improved YOLOv11 detector, where an AC-FPN module is adopted to strengthen multi-scale feature fusion and suppress background interference. Experiments on UAV oilfield datasets demonstrate that the proposed method achieves a precision of 94.25% and a mean average precision (mAP) of 87.54%, outperforming existing approaches. The proposed framework provides an effective and robust solution for oil leakage spot detection under complex illumination. Full article
(This article belongs to the Special Issue AI-Enabled Smart Sensors for Industry Monitoring and Fault Diagnosis)
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22 pages, 4968 KB  
Article
Identification and Biological Characterizations of the Causal Agent of Leaf Spot Disease in Pseudostellaria heterophylla
by Yunbo Kuang, Qian Chen, Felix Abah, Jiyu Su, Yujin Yang, Qiyuan Yang, Zuyun Ye, Zonghua Wang, Meilian Chen and Hongli Hu
Plants 2026, 15(6), 883; https://doi.org/10.3390/plants15060883 - 12 Mar 2026
Viewed by 449
Abstract
Pseudostellaria heterophylla, an important traditional medicinal plant in China, has suffered increasing yield and quality loss due to leaf spot disease in recent years. In this study, the causal agent was conclusively identified as Sclerotiophoma versabilis through detailed morphological characteristics and multi-locus [...] Read more.
Pseudostellaria heterophylla, an important traditional medicinal plant in China, has suffered increasing yield and quality loss due to leaf spot disease in recent years. In this study, the causal agent was conclusively identified as Sclerotiophoma versabilis through detailed morphological characteristics and multi-locus phylogenetic analyses based on the internal transcribed spacer regions (ITS), the 28S large subunit of the nrDNA (LSU), RNA polymerase II (rpb2), and ß-tubulin (tub2) sequences. Pathogenicity tests fulfilled Koch’s postulates, thereby resolving previous taxonomic inconsistencies regarding this disease. The effects of environmental and nutritional factors on mycelial growth, conidial germination, and infection were systematically evaluated. Optimal mycelial growth occurred at 20–25 °C, pH 6–8, under continuous light. Optimal mycelial growth occurred at 20–25 °C, pH 6–8, under continuous light, while conidial germination was maximized at 20–25 °C and pH 6–7 under continuous light. Starch and glycine were identified as the most favorable carbon and nitrogen sources for the fungal mycelial growth, respectively. Infection assays indicated an incubation period of approximately 3 d and maximal disease development at moderate temperatures under low-light conditions, with 6 d-old cultures exhibiting the greatest infectivity. Microscopic observations revealed that S. versabilis penetrated host tissues directly or via stomata without forming specialized infection structures. These findings integrate taxonomic resolution with ecological and infection biology analyses, providing mechanistic insight into the environmental drivers of leaf spot epidemics and a scientific basis for disease-risk assessment and management in P. heterophylla production systems. Full article
(This article belongs to the Collection Plant Disease Diagnostics and Surveillance in Plant Protection)
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11 pages, 2596 KB  
Article
Optical System Design of an Echelle Spectrometer Based on a Digital Micromirror Device
by Jia Liu, Ruikai Zhang, Yangdong Zhou, Dewu Li, Yixin Wang and Lu Yin
Optics 2026, 7(2), 20; https://doi.org/10.3390/opt7020020 - 11 Mar 2026
Viewed by 331
Abstract
The echelle spectrometer utilizes an echelle grating as the primary dispersive element, combined with a prism or planar grating for cross-dispersion, to form a two-dimensional spectral image on an area-array Charge-Coupled Device (CCD). Compared with traditional spectrometers, this configuration provides superior spectral resolution, [...] Read more.
The echelle spectrometer utilizes an echelle grating as the primary dispersive element, combined with a prism or planar grating for cross-dispersion, to form a two-dimensional spectral image on an area-array Charge-Coupled Device (CCD). Compared with traditional spectrometers, this configuration provides superior spectral resolution, broader wavelength coverage, enhanced transient direct-reading capability, and higher energy throughput within a similar footprint. However, the use of area-array detectors significantly increases system cost, limiting adoption in cost-sensitive applications. To reduce cost while maintaining performance, we introduce a digital micromirror device (DMD) as a spatial light modulator to replace the traditional area-array detector, paired with a highly sensitive photomultiplier tube (PMT) for signal acquisition. The designed system operates across a wavelength range of 270 to 800 nm within a compact footprint of approximately 307 mm × 210 mm × 150 mm. The focused spot is accurately positioned on the DMD surface across the entire band, with the root mean square (RMS) spot radius smaller than a single micromirror’s size. Spectral information is efficiently coupled into the PMT via a focusing mirror by selectively flipping the DMD micromirrors for detection. Full article
(This article belongs to the Section Engineering Optics)
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19 pages, 6035 KB  
Article
Design of the Post-Dispersion System for Coherent-Dispersion Spectrometer
by Xiuxiu Zhang, Ruyi Wei, Zhengmao Xie, Rui Yin, Xinghai Liu and Chengsheng Liao
Appl. Sci. 2026, 16(6), 2658; https://doi.org/10.3390/app16062658 - 11 Mar 2026
Viewed by 213
Abstract
Coherent-dispersion spectroscopy enables high-precision Doppler measurements of stellar spectral lines, which serves as a vital technique for the indirect detection of exoplanets. In this study, the post-dispersion system of a coherent-dispersion spectrometer (CODES) was designed and optimized using Zemax, with the detection spectral [...] Read more.
Coherent-dispersion spectroscopy enables high-precision Doppler measurements of stellar spectral lines, which serves as a vital technique for the indirect detection of exoplanets. In this study, the post-dispersion system of a coherent-dispersion spectrometer (CODES) was designed and optimized using Zemax, with the detection spectral range of 656 nm–716 nm and a spectral resolution of 0.06 nm. The relay optical path adopted a combination of a cylindrical lens group and an image slicer, which reshaped the circular spot with a diameter of 630 μm into a linear spot of 27 μm × 2038.8 μm, effectively matching the slit size and improving the light throughput. A flat-field design was employed for the dispersion module, which adopted two structures: the Czerny–Turner spectrometer and the Dyson spectrometer. Both spectrometer structures were designed and optimized, and their aberrations and structural characteristics were comparatively analyzed. The on-axis Modulation Transfer Function (MTF) values at the central wavelength of the two spectrometers were 0.4@37 lp/mm and 0.8@37 lp/mm, respectively, and both the spectral resolution and imaging resolution could meet the design requirements. This work provides a feasible design idea for high-precision CODES for exoplanet detection as well as general medium-to-high resolution spectrometers. Full article
(This article belongs to the Section Applied Physics General)
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