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15 pages, 1321 KiB  
Article
Detection of Cathelicidin-1 and Cathelicidin-2 Biomolecules in the Milk of Goats and Their Use as Biomarkers for the Diagnosis of Mastitis
by Maria V. Bourganou, Dimitra V. Liagka, Konstantinos Vougas, Daphne T. Lianou, Natalia G. C. Vasileiou, Konstantina S. Dimoveli, Antonis P. Politis, Nikos G. Kordalis, Efthymia Petinaki, Vasia S. Mavrogianni, George Th. Tsangaris, George C. Fthenakis and Angeliki I. Katsafadou
Animals 2025, 15(15), 2301; https://doi.org/10.3390/ani15152301 (registering DOI) - 6 Aug 2025
Abstract
The objectives of the present work were as follows: (i) the detection of cathelicidin biomolecules in the milk of individual goats during the early stages of mastitis and their potential use for the diagnosis of mastitis at its early stage and (ii) the [...] Read more.
The objectives of the present work were as follows: (i) the detection of cathelicidin biomolecules in the milk of individual goats during the early stages of mastitis and their potential use for the diagnosis of mastitis at its early stage and (ii) the evaluation of the presence of cathelicidin proteins in the bulk-tank milk from goat and sheep farms. In an experimental study, after inoculation of Staphylococcus simulans into a mammary gland of goats, bacteriological and cytological examinations of milk samples, as well as proteomics examinations [two-dimensional gel electrophoresis analysis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS) analysis] were performed sequentially, from 4 to 48 h post-challenge. Cathelicidin-1 and cathelicidin-2 were detected consistently in milk samples obtained throughout the study, and spot optical densities obtained from PDQuest v.8.0 were recorded. Associations were calculated between the presence of mastitis in a mammary gland at a given timepoint and the detection of cathelicidin proteins in the respective milk sample. All inoculated mammary glands developed mastitis, confirmed by the consistent bacterial isolation from milk samples and the increased somatic cell content therein. Spot optical density of cathelicidin proteins was higher than in samples from contralateral mammary glands. There was a significant association between the presence of mastitis in a mammary gland and the detection of cathelicidin biomolecules in the respective milk sample; the overall accuracy was 81.8% (95% confidence interval: 70.4–90.2%). In a field investigation, the presence of cathelicidin proteins was evaluated in the bulk-tank milk of 32 dairy goat and 57 dairy sheep farms. In this part of the work, no cathelicidin proteins were detected in any bulk-tank milk sample of goat, 0.0% (95% confidence interval: 0.0–10.7%), or sheep, 0.0% (95% confidence interval: 0.0–6.3%), farms. Full article
(This article belongs to the Section Veterinary Clinical Studies)
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19 pages, 298 KiB  
Review
Speaking the Self: How Native-Language Psychotherapy Enables Change in Refugees: A Person-Centered Perspective
by Viktoriya Zipper-Weber
Healthcare 2025, 13(15), 1920; https://doi.org/10.3390/healthcare13151920 (registering DOI) - 6 Aug 2025
Abstract
Background: Since the outbreak of war in Ukraine, countless forcibly displaced individuals facing not only material loss, but also deep psychological distress, have sought refuge across Europe. For those traumatized by war, the absence of a shared language in therapy can hinder healing [...] Read more.
Background: Since the outbreak of war in Ukraine, countless forcibly displaced individuals facing not only material loss, but also deep psychological distress, have sought refuge across Europe. For those traumatized by war, the absence of a shared language in therapy can hinder healing and exacerbate suffering. While cultural diversity in psychotherapy has gained recognition, the role of native-language communication—especially from a person-centered perspective—remains underexplored. Methods: This narrative review with a thematic analysis examines whether and how psychotherapy in the mother tongue facilitates access to therapy and enhances therapeutic efficacy. Four inter-related clusters emerged: (1) the psychosocial context of trauma and displacement; (2) language as a structural gatekeeper to care (RQ1); (3) native-language therapy as a mechanism of change (RQ2); (4) potential risks such as over-identification or therapeutic mismatch (RQ2). Results: The findings suggest that native-language therapy can support the symbolic integration of trauma and foster the core conditions for healing. The implications for multilingual therapy formats, training in interpreter-mediated settings, and future research designs—including longitudinal, transnational studies—are discussed. Conclusions: In light of the current crises, language is not just a tool for access to therapy, but a pathway to psychological healing. Full article
(This article belongs to the Special Issue Healthcare for Immigrants and Refugees)
10 pages, 1248 KiB  
Brief Report
From Nest to Nest: High-Precision GPS-GSM Tracking Reveals Full Natal Dispersal Process in a First-Year Female Montagu’s Harrier Circus pygargus
by Giampiero Sammuri, Guido Alari Esposito, Marta De Paulis, Francesco Pezzo, Andrea Sforzi and Flavio Monti
Birds 2025, 6(3), 40; https://doi.org/10.3390/birds6030040 - 6 Aug 2025
Abstract
This report presents the first complete natal dispersal trajectory of a female Montagu’s Harrier Circus pygargus, tracked in real time from fledging to first breeding using high-resolution continuous Global Positioning System (GPS) telemetry. The bird’s first flight occurred on 26 July 2024, [...] Read more.
This report presents the first complete natal dispersal trajectory of a female Montagu’s Harrier Circus pygargus, tracked in real time from fledging to first breeding using high-resolution continuous Global Positioning System (GPS) telemetry. The bird’s first flight occurred on 26 July 2024, initiating a 31-day post-fledging dependence phase (PFDP), followed by a 23-day pre-migratory phase (PMP), during which it explored areas up to 280.8 km from the nest and eventually settled ca. 190 km away in the Sirente-Velino Regional Park. From there, autumn migration began on 18 September 2024. The bird reached its first wintering site in Mali by 15 October. It used four wintering areas over 178 days, with a winter home range of 37,615.02 km2. Spring migration started on 11 April 2025 and lasted 21 days, ending with arrival in the Gran Sasso e Monti della Laga National Park (Central Italy) on 2 May. The bird used two main sites during the pre-breeding phase (PRBP) before laying eggs on 2 June 2025. The natal dispersal distance, from birthplace to nest site, was 151.28 km. Over 311 days, it covered a total of 14,522.23 km. These findings highlight the value of advanced telemetry in revealing early-life movement ecology and are useful for understanding species-specific patterns of survival, reproduction, and space use and can inform conservation actions. Full article
(This article belongs to the Special Issue Unveiling the Breeding Biology and Life History Evolution in Birds)
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19 pages, 4142 KiB  
Article
Onboard Real-Time Hyperspectral Image Processing System Design for Unmanned Aerial Vehicles
by Ruifan Yang, Min Huang, Wenhao Zhao, Zixuan Zhang, Yan Sun, Lulu Qian and Zhanchao Wang
Sensors 2025, 25(15), 4822; https://doi.org/10.3390/s25154822 - 5 Aug 2025
Abstract
This study proposes and implements a dual-processor FPGA-ARM architecture to resolve the critical contradiction between massive data volumes and real-time processing demands in UAV-borne hyperspectral imaging. The integrated system incorporates a shortwave infrared hyperspectral camera, IMU, control module, heterogeneous computing core, and SATA [...] Read more.
This study proposes and implements a dual-processor FPGA-ARM architecture to resolve the critical contradiction between massive data volumes and real-time processing demands in UAV-borne hyperspectral imaging. The integrated system incorporates a shortwave infrared hyperspectral camera, IMU, control module, heterogeneous computing core, and SATA SSD storage. Through hardware-level task partitioning—utilizing FPGA for high-speed data buffering and ARM for core computational processing—it achieves a real-time end-to-end acquisition–storage–processing–display pipeline. The compact integrated device exhibits a total weight of merely 6 kg and power consumption of 40 W, suitable for airborne platforms. Experimental validation confirms the system’s capability to store over 200 frames per second (at 640 × 270 resolution, matching the camera’s maximum frame rate), quick-look imaging capability, and demonstrated real-time processing efficacy via relative radio-metric correction tasks (processing 5000 image frames within 1000 ms). This framework provides an effective technical solution to address hyperspectral data processing bottlenecks more efficiently on UAV platforms for dynamic scenario applications. Future work includes actual flight deployment to verify performance in operational environments. Full article
(This article belongs to the Section Sensing and Imaging)
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14 pages, 9504 KiB  
Article
Evaluating Habitat Conditions for the Ringlet Butterfly (Erebia pronoe glottis) in a Multi-Use Mountain Landscape in the French Pyrenees
by Martin Wendt and Thomas Schmitt
Diversity 2025, 17(8), 554; https://doi.org/10.3390/d17080554 - 5 Aug 2025
Abstract
We conducted a mark–release–recapture study of the ringlet butterfly, Erebia pronoe glottis, in the Pyrenees to study population density, flight activity, dispersal, and nectar plant preferences. We found differences between both sexes in population density (males: 48/ha; females: 23/ha), sex ratio (2.1), [...] Read more.
We conducted a mark–release–recapture study of the ringlet butterfly, Erebia pronoe glottis, in the Pyrenees to study population density, flight activity, dispersal, and nectar plant preferences. We found differences between both sexes in population density (males: 48/ha; females: 23/ha), sex ratio (2.1), and behaviour (75.4 vs. 20.5% flying). Both sexes used a wide range of nectar plants (Asteraceae, 40.6%; Apiaceae, 34.4%; Caprifoliaceae, 18.8%). However, local abundance appeared to be limited by the availability of nectar plants. Compared to a population of an extensively used pasture in the Alps, a significant increase in flight activity, but not in range, was observed. Movement patterns showed the establishment of home ranges, which significantly limited the dispersal potential, being low for both sexes (mean fight distances-males: 101 m ± 73 SD; females: 68 m ± 80 SD). A sedentary taxon such as E. pronoe glottis does not seem to be able to avoid the pressure of resource shortage by dispersal. As a late-flying pollinator, Erebia pronoe competes seasonally for scarce resources. These are further reduced by grazing pressure and are exploited by honey bees as a superior competitor, resulting in low habitat quality and, consequently, in comparatively low abundance of E. pronoe glottis. Full article
(This article belongs to the Special Issue Biodiversity, Ecology and Conservation of Lepidoptera)
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35 pages, 1824 KiB  
Article
Visual Flight Rules Stabilised Approach: Identifying Human-Factor Influences on Incidents and Accidents During Stabilised Approach, Landing, and Go-Around Flight Phases for General Aviation
by Riya Deshmukh and Arnab Majumdar
Appl. Sci. 2025, 15(15), 8647; https://doi.org/10.3390/app15158647 (registering DOI) - 5 Aug 2025
Abstract
According to the Transportation Safety Board of Canada, between 2013 and 2023, 62% of aviation accidents occurred during the approach, landing, and post-impact phases of flight. Hence, this study targets factors contributing to increased accident rates during the final stages of flight. It [...] Read more.
According to the Transportation Safety Board of Canada, between 2013 and 2023, 62% of aviation accidents occurred during the approach, landing, and post-impact phases of flight. Hence, this study targets factors contributing to increased accident rates during the final stages of flight. It will review how pilot experience influences decision-making and identifies mitigation strategies, focusing on go-arounds to prevent accidents during these critical phases. Surveys and roundtable discussions were conducted to identify factors influencing pilot performance during approach, landing, and go-around manoeuvres. By using a mixed-methods approach that combined thematic and statistical analyses, key safety factors were identified, including situational awareness, decision-making, and operational complexity. The study also examined the relationship between experience and decision-making, highlighting areas for targeted interventions to improve safety. The research emphasises the importance of integrating decision-making considerations into training programmes and connecting these to human factors. Through identifying areas for improvement, this study offers a safety-driven framework to address decision-making challenges during approach, landing, and go-around phases, with the objective of reducing accident and incident rates in general aviation. Full article
(This article belongs to the Special Issue Research on Aviation Safety)
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22 pages, 5136 KiB  
Article
Application of UAVs to Support Blast Design for Flyrock Mitigation: A Case Study from a Basalt Quarry
by Józef Pyra and Tomasz Żołądek
Appl. Sci. 2025, 15(15), 8614; https://doi.org/10.3390/app15158614 (registering DOI) - 4 Aug 2025
Viewed by 74
Abstract
Blasting operations in surface mining pose a risk of flyrock, which is a critical safety concern for both personnel and infrastructure. This study presents the use of unmanned aerial vehicles (UAVs) and photogrammetric techniques to improve the accuracy of blast design, particularly in [...] Read more.
Blasting operations in surface mining pose a risk of flyrock, which is a critical safety concern for both personnel and infrastructure. This study presents the use of unmanned aerial vehicles (UAVs) and photogrammetric techniques to improve the accuracy of blast design, particularly in relation to controlling burden values and reducing flyrock. The research was conducted in a basalt quarry in Lower Silesia, where high rock fracturing complicated conventional blast planning. A DJI Mavic 3 Enterprise UAV was used to capture high-resolution aerial imagery, and 3D models were created using Strayos software. These models enabled precise analysis of bench face geometry and burden distribution with centimeter-level accuracy. The results showed a significant improvement in identifying zones with improper burden values and allowed for real-time corrections in blasthole design. Despite a ten-fold reduction in the number of images used, no loss in model quality was observed. UAV-based surveys followed software-recommended flight paths, and the application of this methodology reduced the flyrock range by an average of 42% near sensitive areas. This approach demonstrates the operational benefits and enhanced safety potential of integrating UAV-based photogrammetry into blasting design workflows. Full article
(This article belongs to the Special Issue Advanced Blasting Technology for Mining)
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14 pages, 18722 KiB  
Article
Safe Autonomous UAV Target-Tracking Under External Disturbance, Through Learned Control Barrier Functions
by Promit Panja, Madan Mohan Rayguru and Sabur Baidya
Robotics 2025, 14(8), 108; https://doi.org/10.3390/robotics14080108 - 3 Aug 2025
Viewed by 123
Abstract
Ensuring the safe operation of Unmanned Aerial Vehicles (UAVs) is crucial for both mission-critical and safety-critical tasks. In scenarios where UAVs must track airborne targets, they need to follow the target’s path while maintaining a safe distance, even in the presence of unmodeled [...] Read more.
Ensuring the safe operation of Unmanned Aerial Vehicles (UAVs) is crucial for both mission-critical and safety-critical tasks. In scenarios where UAVs must track airborne targets, they need to follow the target’s path while maintaining a safe distance, even in the presence of unmodeled dynamics and environmental disturbances. This paper presents a novel collision avoidance strategy for dynamic quadrotor UAVs during target-tracking missions. We propose a safety controller that combines a learning-based Control Barrier Function (CBF) with standard sliding mode feedback. Our approach employs a neural network that learns the true CBF constraint, accounting for wind disturbances, while the sliding mode controller addresses unmodeled dynamics. This unified control law ensures safe leader-following behavior and precise trajectory tracking. By leveraging a learned CBF, the controller offers improved adaptability to complex and unpredictable environments, enhancing both the safety and robustness of the system. The effectiveness of our proposed method is demonstrated through the AirSim platform using the PX4 flight controller. Full article
(This article belongs to the Special Issue Applications of Neural Networks in Robot Control)
25 pages, 2567 KiB  
Article
Development of Improved Empirical Take-Off Equations
by Timothy T. Takahashi
Aerospace 2025, 12(8), 695; https://doi.org/10.3390/aerospace12080695 - 2 Aug 2025
Viewed by 197
Abstract
This paper develops empirical relationships to estimate FAA/EASA and MIL-3013B rules-compliant take-off field performance for single and multi-engine aircraft. Recent experience with modern aircraft flight manuals revealed that popular empirical legacy methods are no longer accurate; improvements in tires and brakes lead to [...] Read more.
This paper develops empirical relationships to estimate FAA/EASA and MIL-3013B rules-compliant take-off field performance for single and multi-engine aircraft. Recent experience with modern aircraft flight manuals revealed that popular empirical legacy methods are no longer accurate; improvements in tires and brakes lead to significantly shorter certified distances. This work relies upon a survey of current operational aircraft and extensive numerical simulations of generic configurations to support the development of a collection of new equations to estimate take-off performance for single and multi-engine aircraft under dry and wet conditions. These relationships are individually tailored for civilian and U.S. Military rules; they account for the superior capability of modern braking systems and the implications of minimum-control speed on the certified distance. Full article
(This article belongs to the Special Issue Aircraft Conceptual Design: Tools, Processes and Examples)
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35 pages, 782 KiB  
Systematic Review
A Systematic Literature Review on PHM Strategies for (Hydraulic) Primary Flight Control Actuation Systems
by Leonardo Baldo, Andrea De Martin, Giovanni Jacazio and Massimo Sorli
Actuators 2025, 14(8), 382; https://doi.org/10.3390/act14080382 - 2 Aug 2025
Viewed by 93
Abstract
Prognostic and Health Management (PHM) strategies are gaining increasingly more traction in almost every field of engineering, offering stakeholders advanced capabilities in system monitoring, anomaly detection, and predictive maintenance. Primary flight control actuators are safety-critical elements within aircraft flight control systems (FCSs), and [...] Read more.
Prognostic and Health Management (PHM) strategies are gaining increasingly more traction in almost every field of engineering, offering stakeholders advanced capabilities in system monitoring, anomaly detection, and predictive maintenance. Primary flight control actuators are safety-critical elements within aircraft flight control systems (FCSs), and currently, they are mainly based on Electro-Hydraulic Actuators (EHAs) or Electro-Hydrostatic Actuators (EHSAs). Despite the widespread diffusion of PHM methodologies, the application of these technologies for EHAs is still somewhat limited, and the available information is often restricted to the industrial sector. To fill this gap, this paper provides an in-depth analysis of state-of-the-art EHA PHM strategies for aerospace applications, as well as their limitations and further developments through a Systematic Literature Review (SLR). An objective and clear methodology, combined with the use of attractive and informative graphics, guides the reader towards a thorough investigation of the state of the art, as well as the challenges in the field that limit a wider implementation. It is deemed that the information presented in this review will be useful for new researchers and industry engineers as it provides indications for conducting research in this specific and still not very investigated sector. Full article
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17 pages, 1195 KiB  
Article
Phytochemical Profiling, Antioxidant Capacity, and α-Amylase/α-Glucosidase Inhibitory Effects of 29 Faba Bean (Vicia faba L.) Varieties from China
by Ying Li, Zhihua Wang, Chengkai Mei, Wenqi Sun, Xingxing Yuan, Jing Wang and Wuyang Huang
Biology 2025, 14(8), 982; https://doi.org/10.3390/biology14080982 (registering DOI) - 2 Aug 2025
Viewed by 197
Abstract
Faba bean (Vicia faba L.), a nutrient-rich legume beneficial to human health, is valued for its high L-3,4-dihydroxyphenylalanine (L-DOPA) and phenolic content. This study investigated phytochemical diversity and bioactivity across 29 Chinese faba bean varieties. Phenolics were profiled using ultrahigh-performance liquid chromatography [...] Read more.
Faba bean (Vicia faba L.), a nutrient-rich legume beneficial to human health, is valued for its high L-3,4-dihydroxyphenylalanine (L-DOPA) and phenolic content. This study investigated phytochemical diversity and bioactivity across 29 Chinese faba bean varieties. Phenolics were profiled using ultrahigh-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) and quantified via high-performance liquid chromatography (HPLC). Antioxidant capacity was evaluated, including DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid)) radical scavenging activity, and ferric reducing antioxidant power (FRAP), along with α-amylase/α-glucosidase inhibitory effects. Twenty-five phenolics were identified, including L-DOPA (11.96–17.93 mg/g, >70% of total content), seven phenolic acids, and seventeen flavonoids. L-DOPA showed potent enzyme inhibition (IC50 values of 22.45 μM for α-amylase and 16.66 μM for α-glucosidase) but demonstrated limited antioxidant effects. Lincan 13 (Gansu) exhibited the strongest antioxidant activity (DPPH, 16.32 μmol trolox/g; ABTS, 5.85 μmol trolox/g; FRAP, 21.38 mmol Fe2+/g), which correlated with it having the highest flavonoid content (40.51 mg rutin/g), while Yican 4 (Yunnan) showed the strongest α-amylase inhibition (43.33%). Correlation analysis confirmed flavonoids as the primary antioxidants, and principal component analysis (PCA) revealed geographical trends (e.g., Jiangsu varieties were particularly phenolic-rich). These findings highlight faba beans’ potential as functional foods and guide genotype selection in targeted breeding programs aimed at enhancing health benefits. Full article
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33 pages, 7206 KiB  
Article
From Development to Regeneration: Insights into Flight Muscle Adaptations from Bat Muscle Cell Lines
by Fengyan Deng, Valentina Peña, Pedro Morales-Sosa, Andrea Bernal-Rivera, Bowen Yang, Shengping Huang, Sonia Ghosh, Maria Katt, Luciana Andrea Castellano, Lucinda Maddera, Zulin Yu, Nicolas Rohner, Chongbei Zhao and Jasmin Camacho
Cells 2025, 14(15), 1190; https://doi.org/10.3390/cells14151190 - 1 Aug 2025
Viewed by 227
Abstract
Skeletal muscle regeneration depends on muscle stem cells, which give rise to myoblasts that drive muscle growth, repair, and maintenance. In bats—the only mammals capable of powered flight—these processes must also sustain contractile performance under extreme mechanical and metabolic stress. However, the cellular [...] Read more.
Skeletal muscle regeneration depends on muscle stem cells, which give rise to myoblasts that drive muscle growth, repair, and maintenance. In bats—the only mammals capable of powered flight—these processes must also sustain contractile performance under extreme mechanical and metabolic stress. However, the cellular and molecular mechanisms underlying bat muscle physiology remain largely unknown. To enable mechanistic investigation of these traits, we established the first myoblast cell lines from the pectoralis muscle of Pteronotus mesoamericanus, a highly maneuverable aerial insectivore. Using both spontaneous immortalization and exogenous hTERT/CDK4 gene overexpression, we generated two stable cell lines that retain proliferative capacity and differentiate into contractile myotubes. These cells exhibit frequent spontaneous contractions, suggesting robust functional integrity at the neuromuscular junction. In parallel, we performed transcriptomic and metabolic profiling of native pectoralis tissue in the closely related Pteronotus parnellii to define molecular programs supporting muscle specialization. Gene expression analyses revealed enriched pathways for muscle metabolism, development, and regeneration, highlighting supporting roles in tissue maintenance and repair. Consistent with this profile, the flight muscle is triglyceride-rich, which serves as an important fuel source for energetically demanding processes, including muscle contraction and cellular recovery. Integration of transcriptomic and metabolic data identified three key metabolic modules—glucose utilization, lipid handling, and nutrient signaling—that likely coordinate ATP production and support metabolic flexibility. Together, these complementary tools and datasets provide the first in vitro platform for investigating bat muscle research, enabling direct exploration of muscle regeneration, metabolic resilience, and evolutionary physiology. Full article
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27 pages, 21019 KiB  
Article
A UWB-AOA/IMU Integrated Navigation System for 6-DoF Indoor UAV Localization
by Pengyu Zhao, Hengchuan Zhang, Gang Liu, Xiaowei Cui and Mingquan Lu
Drones 2025, 9(8), 546; https://doi.org/10.3390/drones9080546 - 1 Aug 2025
Viewed by 239
Abstract
With the increasing deployment of unmanned aerial vehicles (UAVs) in indoor environments, the demand for high-precision six-degrees-of-freedom (6-DoF) localization has grown significantly. Ultra-wideband (UWB) technology has emerged as a key enabler for indoor UAV navigation due to its robustness against multipath effects and [...] Read more.
With the increasing deployment of unmanned aerial vehicles (UAVs) in indoor environments, the demand for high-precision six-degrees-of-freedom (6-DoF) localization has grown significantly. Ultra-wideband (UWB) technology has emerged as a key enabler for indoor UAV navigation due to its robustness against multipath effects and high-accuracy ranging capabilities. However, conventional UWB-based systems primarily rely on range measurements, operate at low measurement frequencies, and are incapable of providing attitude information. This paper proposes a tightly coupled error-state extended Kalman filter (TC–ESKF)-based UWB/inertial measurement unit (IMU) fusion framework. To address the challenge of initial state acquisition, a weighted nonlinear least squares (WNLS)-based initialization algorithm is proposed to rapidly estimate the UAV’s initial position and attitude under static conditions. During dynamic navigation, the system integrates time-difference-of-arrival (TDOA) and angle-of-arrival (AOA) measurements obtained from the UWB module to refine the state estimates, thereby enhancing both positioning accuracy and attitude stability. The proposed system is evaluated through simulations and real-world indoor flight experiments. Experimental results show that the proposed algorithm outperforms representative fusion algorithms in 3D positioning and yaw estimation accuracy. Full article
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16 pages, 2858 KiB  
Article
Reactive Aerosol Jet Printing of Ag Nanoparticles: A New Tool for SERS Substrate Preparation
by Eugenio Gibertini, Lydia Federica Gervasini, Jody Albertazzi, Lorenzo Maria Facchetti, Matteo Tommasini, Valentina Busini and Luca Magagnin
Coatings 2025, 15(8), 900; https://doi.org/10.3390/coatings15080900 (registering DOI) - 1 Aug 2025
Viewed by 118
Abstract
The detection of trace chemicals at low and ultra-low concentrations is critical for applications in environmental monitoring, medical diagnostics, food safety and other fields. Conventional detection techniques often lack the required sensitivity, specificity, or cost-effectiveness, making real-time, in situ analysis challenging. Surface-enhanced Raman [...] Read more.
The detection of trace chemicals at low and ultra-low concentrations is critical for applications in environmental monitoring, medical diagnostics, food safety and other fields. Conventional detection techniques often lack the required sensitivity, specificity, or cost-effectiveness, making real-time, in situ analysis challenging. Surface-enhanced Raman spectroscopy (SERS) is a powerful analytical tool, offering improved sensitivity through the enhancement of Raman scattering by plasmonic nanostructures. While noble metals such as Ag and Au are currently the reference choices for SERS substrates, fabrication methods should balance enhancement efficiency, reproducibility and scalability. In this study, we propose a novel approach for SERS substrate fabrication using reactive Aerosol Jet Printing (r-AJP) as an innovative additive manufacturing technique. The r-AJP process enables in-flight Ag seed reduction and nucleation of Ag nanoparticles (NPs) by mixing silver nitrate and ascorbic acid aerosols before deposition, as suggested by computational fluid dynamics (CFD) simulations. The resulting coatings were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses, revealing the formation of nanoporous crystalline Ag agglomerates partially covered by residual matter. The as-prepared SERS substrates exhibited remarkable SERS activity, demonstrating a high enhancement factor (106) for rhodamine (R6G) detection. Our findings highlight the potential of r-AJP as a scalable and cost-effective fabrication strategy for next-generation SERS sensors, paving the way for the development of a new additive manufacturing tool for noble metal material deposition. Full article
(This article belongs to the Section Surface Characterization, Deposition and Modification)
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20 pages, 17646 KiB  
Article
An Observational Study of a Severe Squall Line Crossing Hong Kong on 15 March 2025 Based on Radar-Retrieved Three-Dimensional Winds and Flight Data
by Pak-wai Chan, Ying-wa Chan, Ping Cheung and Man-lok Chong
Appl. Sci. 2025, 15(15), 8562; https://doi.org/10.3390/app15158562 (registering DOI) - 1 Aug 2025
Viewed by 181
Abstract
The present paper reports for the first time the comparison of radar-derived eddy dissipation rate (EDR) and vertical velocity with measurements from six aircraft for an intense squall line crossing Hong Kong. The study objectives are three-fold: (i) to characterise the structural dynamics [...] Read more.
The present paper reports for the first time the comparison of radar-derived eddy dissipation rate (EDR) and vertical velocity with measurements from six aircraft for an intense squall line crossing Hong Kong. The study objectives are three-fold: (i) to characterise the structural dynamics of the intense squall line; (ii) to identify the dynamical change in EDR and vertical velocity during its eastward propagation across Hong Kong with a view to gaining insight into the intensity change of the squall line and the severity of its impact on aircraft flying near it; (iii) to carry out quantitative comparison of EDR and vertical velocity derived from remote sensing instruments, i.e., weather radars and in situ measurements from aircraft, so that the quality of the former dataset can be evaluated by the latter. During the passage of the squall line and taking reference of the radar reflectivity, vertical circulation and the subsiding flow at the rear, it appeared to be weakening in crossing over Hong Kong, possibly due to land friction by terrain and urban morphology. This is also consistent with the maximum gusts recorded by the dense network of ground-based anemometers in Hong Kong. However, from the EDR and the vertical velocity of the aircraft, the weakening trend was not very apparent, and rather severe turbulence was still recorded by the aircraft flying through the squall line into the region with stratiform precipitation when the latter reached the eastern coast of Hong Kong. In general, the radar-based and the aircraft-based EDRs are consistent with each other. The radar-retrieved maximum vertical velocity may be smaller in magnitude at times, possibly arising from the limited spatial and temporal resolutions of the aircraft data. The results of this paper could be a useful reference for the development of radar-based turbulence products for aviation applications. Full article
(This article belongs to the Section Environmental Sciences)
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