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23 pages, 2308 KB  
Article
Modeling Wolf, Canis lupus, Recolonization Dynamics to Plan Conservation Actions Ahead: Will the “Big Bad Wolves” Howl Again in Slavonia, Croatia?
by Matko Bišćan, Dušan Jelić, Ivana Maguire and Alessandro Massolo
Diversity 2025, 17(7), 461; https://doi.org/10.3390/d17070461 - 28 Jun 2025
Cited by 1 | Viewed by 2104
Abstract
A century ago, wolves ranged throughout Croatia but were eradicated from Slavonia—a region that could serve as a crucial corridor connecting the Carpathian and Dinaric–Balkan wolf populations. Such a corridor would promote genetic exchange and help maintain ecosystem stability. Recent wolf sightings in [...] Read more.
A century ago, wolves ranged throughout Croatia but were eradicated from Slavonia—a region that could serve as a crucial corridor connecting the Carpathian and Dinaric–Balkan wolf populations. Such a corridor would promote genetic exchange and help maintain ecosystem stability. Recent wolf sightings in Slavonia indicate that natural recolonization may be possible. Understanding how this process unfolds under different management scenarios is essential for minimizing conflicts and supporting successful recolonization. In this study, we modeled wolf population dynamics in Slavonia and surrounding areas using 11 scenarios, grouped into three categories: adverse events, increased carrying capacity, and population supplementation. These scenarios encompassed various management strategies, including a baseline scenario and others designed to address system uncertainties. Our results show that scenarios involving corridor construction and wolf translocation have the lowest probability of extinction. In contrast, adverse events carry a high risk of extinction, and simply expanding suitable habitats is not enough to ensure population viability. These findings underscore the importance of integrated conservation strategies that combine habitat corridors, population management, and conflict mitigation. Long-term planning is critical, as differences in outcomes become more pronounced over time. Connectivity with stable neighboring populations is vital for the long-term survival of wolves in the region. Future research should investigate whether protected areas alone are sufficient to sustain wolves as apex predators or if large-scale ecosystem restoration—including trophic rewilding—is necessary for successful recolonization. Full article
(This article belongs to the Special Issue Wildlife in Natural and Altered Environments)
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26 pages, 4252 KB  
Article
Vertebrate Diversity of the Middle Triassic Xingyi Fauna
by Da-yong Jiang, Andrea Tintori, Min Zhou, Ryosuke Motani, Cheng Ji, Olivier Rieppel, Nicholas C. Fraser, Davide Conedera, Ming-tao Yao, Yi-nuo Wang and Zuo-yu Sun
Diversity 2025, 17(7), 453; https://doi.org/10.3390/d17070453 - 26 Jun 2025
Cited by 1 | Viewed by 1585
Abstract
The Xingyi Fauna yields abundant and well-articulated skeletons of Ladinian (Middle Triassic, ab. 240 Ma) marine reptiles, associated with fishes, conodonts, crinoids, ammonoids, bivalves, arthropods, and other fossils including nannofossils and coprolites. It represents a new marine ecosystem fully developed after the end-Permian [...] Read more.
The Xingyi Fauna yields abundant and well-articulated skeletons of Ladinian (Middle Triassic, ab. 240 Ma) marine reptiles, associated with fishes, conodonts, crinoids, ammonoids, bivalves, arthropods, and other fossils including nannofossils and coprolites. It represents a new marine ecosystem fully developed after the end-Permian Mass Extinction, and characterized by the appearance of a diversity of large marine reptiles with large ichthyosaurs as the apex predators. Twenty marine reptile and 17 fish species have been reported. The sequence of the Xingyi Fauna records the transition from a marine ecosystem dominated by air-breathing tetrapods extending across the shallow platform to the deep ocean, as indicated by large marine reptiles with a capability for long-distance cruising into the outer sea. The faunal composition of the Lower Assemblage of the Xingyi Fauna, dominated by small- to medium-sized pachypleurosaurids and nothosaurids, is similar to that of the older Anisian Panxian Fauna and the western Tethyan Monte San Giorgio Fauna, but the faunal composition of the Upper Assemblage, with large ichthyopterygians, pistosauroid sauropterygians, and flying fishes, is similar to that of the younger Carnian Guanling Biota as well as the Raibl and Polzberg Faunas in the Alps and California. Therefore, the Xingyi Fauna can be considered a hub of paleobiogeological exchange connecting the western Tethys and the eastern Pathalassa. Full article
(This article belongs to the Section Marine Diversity)
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21 pages, 4914 KB  
Article
Land Use Effects on the Space Use and Dispersal of an Apex Predator in an Ecotone Between Tropical Biodiversity Hotspots
by Bernardo Brandão Niebuhr, Sandra M. C. Cavalcanti, Ermeson A. Vilalba, Vanessa V. Alberico, João Carlos Zecchini Gebin, Danilo da Costa Santos, Ananda de Barros Barban, Raphael de Oliveira, Eliezer Gurarie and Ronaldo G. Morato
Diversity 2025, 17(6), 435; https://doi.org/10.3390/d17060435 - 19 Jun 2025
Viewed by 1784
Abstract
Assessing the ranging and dispersal behavior of apex predators and its consequences for landscape connectivity is of paramount importance for understanding population and ecosystem effects of anthropogenic land use change. Here, we synthesize ranging and dispersal ecological information on pumas (Puma concolor [...] Read more.
Assessing the ranging and dispersal behavior of apex predators and its consequences for landscape connectivity is of paramount importance for understanding population and ecosystem effects of anthropogenic land use change. Here, we synthesize ranging and dispersal ecological information on pumas (Puma concolor) and present estimates of how different land uses affect the space use and dispersal of pumas on fragmented landscapes in an ecotone between biodiversity hotspots in southeastern Brazil. Additionally, we evaluate the effect of animal translocations on dispersal and movement patterns. Using location data for 14 GPS-collared pumas and land use data, we assessed when, how long, and how far individuals dispersed; how forest loss and infrastructure influenced puma home range size; and how movement patterns changed according to land use and proximity to infrastructure, during ranging and dispersal, for residents, natural dispersers, and translocated individuals. We present the first detailed record on the dispersal of pumas in Brazil and in the tropics, including long-distance dispersals, and show that pumas moved faster and more linearly during dispersal than during ranging. Their movement was slower and their home ranges were smaller in more forested areas, underscoring the importance of forest as habitat. In contrast, movement rates were higher in open pastures, mainly during dispersal. Our study underscores the scarcity of research on puma space use and dispersal in South America and reveals partial divergences in dispersal behaviors compared to North America and temperate regions, especially concerning dispersal ages. Furthermore, we give the first steps in presenting how land cover and human infrastructure affect the movement of this apex predator in a tropical ecosystem, an important subsidy for land use management. We call for more comprehensive studies on the movement ecology of carnivores combined with long-term population monitoring, to allow linking individual behavior with metapopulation dynamics and landscape connectivity and drawing more effective measures to sustain their populations. Full article
(This article belongs to the Special Issue Landscape Biodiversity)
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24 pages, 3082 KB  
Article
Accuracy of Dynamic Computer-Aided Implant Surgery for Biconometric Implant Positioning: A Retrospective Case Series Analysis
by Luca Comuzzi, Tea Romasco, Massimo Del Fabbro, Margherita Tumedei, Luca Signorini, Francesco Inchingolo, Lorenzo Montesani, Giulia Marchioli, Carlos Fernando Mourão, Adriano Piattelli and Natalia Di Pietro
Osteology 2025, 5(2), 18; https://doi.org/10.3390/osteology5020018 - 16 Jun 2025
Viewed by 1682
Abstract
Background/Objectives: This retrospective study assessed the accuracy of implant positioning with dynamic computer-aided implant surgery (dCAIS) for Toronto Bridge fabrication, using a conometric prosthetic concept and a new intraoral splinting technique (CLIKSS). It compared discrepancies across various anatomical regions, bone qualities, and implant [...] Read more.
Background/Objectives: This retrospective study assessed the accuracy of implant positioning with dynamic computer-aided implant surgery (dCAIS) for Toronto Bridge fabrication, using a conometric prosthetic concept and a new intraoral splinting technique (CLIKSS). It compared discrepancies across various anatomical regions, bone qualities, and implant sites. Methods: This study involved 52 patients undergoing full-arch rehabilitation (17 in the mandible, 30 in the maxilla, and 5 in both), with 366 implants placed (125 in the mandible, 241 in the maxilla; 128 in post-extraction sites, and the remainder in healed sites). All implants were immediately loaded. Precision was assessed by measuring linear and three-dimensional (3D) angular deviations between planned and actual implant positions. Results: Measurement errors for apical linear and 3D deviations at the apex and entry point ranged from 0.24 ± 0.10 to 0.55 ± 0.57 mm, and angular deviations varied from 0.32 ± 0.65° to 0.35 ± 0.71°. Maxillary measurements were significantly higher at the entry, apical, and vertical levels, even when comparing anterior and posterior regions with the corresponding mandibular areas, while no differences were found in the angular deviation. Significant discrepancies were observed among different mandibular bone types. Maxillary post-extraction sites exhibited significantly greater deviations than mandibular sites in all parameters except angular deviation. No significant differences were found between healed and post-extraction sites within the same jaw. Conclusions: dCAIS improved implant placement accuracy, leading to predictable prosthetic outcomes, especially during parallel multi-implant insertions. This report introduced dCAIS for conometric/biconometric implant placement combined with the innovative CLIKSS technique as an effective intraoral split method for this prosthesis connection. Full article
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14 pages, 603 KB  
Review
SIU-ICUD: Focal Therapy for PCa — The Technique
by Lara Rodriguez-Sanchez, Thomas J. Polascik, Kara Watts, Peter Ka-Fung Chiu, Mark Emberton, Behfar Ehdaie, Hashim U. Ahmed, Andre Abreu, Ardeshir R. Rastinehad and Rafael Sanchez-Salas
Soc. Int. Urol. J. 2025, 6(3), 38; https://doi.org/10.3390/siuj6030038 - 7 Jun 2025
Cited by 2 | Viewed by 2404
Abstract
Background/Objectives: Focal therapy (FT) and technology are closely connected. Advanced imaging allows for precise identification of the index lesion, enabling the targeted use of various thermal and non-thermal energy sources through different approaches, with specific techniques tailored to lesion location and operator expertise. [...] Read more.
Background/Objectives: Focal therapy (FT) and technology are closely connected. Advanced imaging allows for precise identification of the index lesion, enabling the targeted use of various thermal and non-thermal energy sources through different approaches, with specific techniques tailored to lesion location and operator expertise. This personalized approach enhances both safety and effectiveness, facilitating customized treatment planning. Methods: The International Consultation on Urological Diseases formed a committee to review the current literature on FT for prostate cancer (PCa), focusing specifically on the technique. Following in-depth discussions, the committee chose a “by lesion” approach rather than the traditional “by energy” approach to structure the review. A comprehensive PubMed search was conducted to gather relevant articles on the various energy modalities and procedural approaches used in FT for PCa. Results: Lesions in the apex, anterior, and posterior regions of the prostate can be accessed through several FT approaches, each associated with specific energy modalities and techniques. The transrectal approach utilizes high-intensity focused ultrasound (HIFU) and focal laser ablation (FLA), while the transperineal approach is compatible with energy sources such as cryotherapy, irreversible electroporation (IRE), brachytherapy, and FLA. The transurethral approach supports methods such as transurethral ultrasound ablation (TULSA). Each approach offers distinct advantages based on lesion location, treatment area, and energy modality. The choice of technique evaluated the safety and efficacy of each energy source and approach based on specific treatment areas within the prostate, highlighting the need for robust research across lesion locations and modalities, rather than focusing solely on each modality for a specific region. Conclusions: FT is rapidly advancing with new energy sources, technological improvements, and increasing operator expertise. To further optimize FT, research should prioritize evaluating the safety and effectiveness of different energy sources for various lesion locations, focusing on the treatment area rather than the energy modality itself. Full article
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11 pages, 1923 KB  
Article
Clinical Outcomes in the Treatment of Pertrochanteric Femur Fractures: A Retrospective Cohort Study
by Cesare Donadono, Domenico Tigani, Andrea Assenza, Davide Censoni, Francesco Pesce and Giuseppe Melucci
J. Pers. Med. 2025, 15(5), 202; https://doi.org/10.3390/jpm15050202 - 19 May 2025
Cited by 1 | Viewed by 1165
Abstract
Background: Pertrochanteric fractures of the proximal femur present a common challenge for traumatologists, with intramedullary nailing emerging as the preferred treatment. Complication rates are around 20%, including screw jamming, refractures, implant breakage, or medial migration, with cut-out being the most common. A tip–apex [...] Read more.
Background: Pertrochanteric fractures of the proximal femur present a common challenge for traumatologists, with intramedullary nailing emerging as the preferred treatment. Complication rates are around 20%, including screw jamming, refractures, implant breakage, or medial migration, with cut-out being the most common. A tip–apex distance (TAD) of >25 mm and incorrect cephalic screw position are predictive factors for cut-out. This study assesses outcomes using the Elos intramedullary nail, based on the experience of the Department of Orthopedics and Traumatology at Ospedale Maggiore in Bologna. Methods: We conducted a retrospective cohort study of 344 patients treated with the Elos intramedullary nail for pertrochanteric femoral fractures from 1 January 2017 to 31 December 2022. The Elos®-Intrauma nail was implanted using the standard technique. Initial X-rays classified fractures according to the AO-OTA classification, and postoperative X-rays confirmed the cephalic screw’s placement per Cleveland’s regions. Patients were divided into two groups: optimal cephalic screw position (positions 5-8-9) and other positions. We evaluated TAD, calcar-referred TAD (CalTAD), and postoperative reduction quality using Chang’s criteria. The incidence of cut-out and other complications were assessed in connection with these measurements. Results: Among the 344 patients, 227 (65.9%) had the screw in positions 5-8-9, while 117 (34.1%) had it in other positions. The median TAD was 19.47 ± 6.26 mm (range 3.96–46.6), with TAD ≤ 25 mm in 265 patients (77%). The median CalTAD was 22.37 ± 5.65 mm (range 8.75–45.3), with CalTAD ≤ 25 mm in 231 patients (67.1%). According to Chang’s criteria, 8 cases (2.3%) had poor reduction, 139 cases (40.4%) had acceptable reduction, and 197 cases (57.3%) had excellent reduction. Cut-out occurred in four cases (1.19%). Multivariate analysis revealed only poor reduction and TAD > 25 mm as independent predictors of cut-out (p < 0.05), while cephalic screw position, CalTAD, and fracture type did not impact cut-out incidence. Conclusions: This study indicates that optimal TAD and quality of reduction are crucial for minimizing cut-out risks. The Elos intramedullary nail shows favorable outcomes with a low cut-out incidence when these parameters are met. Emphasis should be placed on achieving a TAD ≤ 25 mm and excellent reduction quality to reduce complications. Full article
(This article belongs to the Special Issue Orthopedic Trauma: New Perspectives and Innovative Techniques)
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16 pages, 1477 KB  
Review
Atherosclerosis and Chronic Apical Periodontitis: Systematic Review and Meta-Analysis
by María León-López, Daniel Cabanillas-Balsera, Jenifer Martín-González, Benito Sánchez-Domínguez, Juan J. Saúco-Márquez and Juan J. Segura-Egea
J. Clin. Med. 2025, 14(5), 1504; https://doi.org/10.3390/jcm14051504 - 24 Feb 2025
Cited by 4 | Viewed by 2839
Abstract
Background: Atherosclerosis is a chronic and progressive condition of the arteries, characterized by the thickening and hardening of their walls due to the formation of atherosclerotic plaques. Low-grade inflammation is implicated in the pathogeny of atherosclerosis. Chronic apical periodontitis (CAP), the chronic inflammation [...] Read more.
Background: Atherosclerosis is a chronic and progressive condition of the arteries, characterized by the thickening and hardening of their walls due to the formation of atherosclerotic plaques. Low-grade inflammation is implicated in the pathogeny of atherosclerosis. Chronic apical periodontitis (CAP), the chronic inflammation around the root apex of infected teeth, is associated with a low-grade inflammatory state, and thus a connection between atherosclerosis and CAP has been suggested. The aim of this study was to conduct a systematic review with meta-analysis to answer the following PICO question: In adult patients, does the presence or absence of atherosclerosis affect the prevalence of CAP? Methods: The PRISMA guidelines were followed to carry out this systematic review, which was registered in PROSPERO (651359). A bibliographic search was performed in PubMed-MEDLINE, Embase, and Scielo. The inclusion criteria selected studies presenting data on the prevalence of CAP in patients diagnosed with atherosclerosis and control patients. The statistical analysis was carried out using RevMan software v.5.4. The study characteristics and risk ratios with 95% confidence intervals (CIs) were extracted. Random-effects meta-analyses were performed. Risk of bias was assessed using the Newcastle-Ottawa scale, which was adapted for cross-sectional studies. To estimate variance and heterogeneity between trials, the Higgins I2 test was used. The quality of the evidence was evaluated using GRADE. Results: The search strategy recovered 102 articles, and only five met the inclusion criteria. Meta-analysis showed an overall OR = 2.94 (95% CI = 1.83–4.74; p < 0.01) for the prevalence of CAP among patients with atherosclerosis. The overall risk of bias was moderate. The quality of the evidence showed a low level of certainty. Conclusions: Patients with atherosclerosis are almost three times more likely to have CAP. This finding supports the hypothesis that chronic inflammatory processes in the oral cavity could significantly impact cardiovascular health, emphasizing the importance of an integrated approach to oral and systemic health care. This result should be translated to daily clinical practice, and the healthcare community should be aware of this association and suspect atherosclerotic pathology in patients who show a high prevalence of CAP. Likewise, patients with atherosclerosis should be monitored in the dental clinic for CAP. Full article
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15 pages, 7432 KB  
Article
Automated Fixed System Specifically Designed for Agrochemical Applications in Protected Crops
by Souraya Benalia, Antonio Mantella, Matteo Sbaglia, Lorenzo M. M. Abenavoli and Bruno Bernardi
Agriculture 2025, 15(3), 330; https://doi.org/10.3390/agriculture15030330 - 2 Feb 2025
Cited by 1 | Viewed by 1103
Abstract
Protected crops are intensive production systems characterized by high vegetation density, high temperatures, and high moisture, making them favorable environments for the development of pests and diseases. Consequently, these systems often require several interventions with agrochemicals to maintain profitable yields and high produce [...] Read more.
Protected crops are intensive production systems characterized by high vegetation density, high temperatures, and high moisture, making them favorable environments for the development of pests and diseases. Consequently, these systems often require several interventions with agrochemicals to maintain profitable yields and high produce quality. However, the application of plant protection products (PPPs) in such systems is not efficient and poses environmental concerns. This study aims at analysing spray behaviour, particularly in terms of foliar deposition and losses to the ground according to spraying equipment and foliage height, focusing on a specifically designed and developed system for agrochemical application in protected crops, and comparing it with a commonly used spraying system, namely, the cannon sprayer. Such a system consists in a fixed net of tubing and anti-drip nozzles positioned at the top of the greenhouse’s apex, connected to a pneumatic sprayer ‘Special Serre 2000’ outside the greenhouse. Findings revealed a significant effect of the spraying system (Kruskal–Wallis χ2 = 12.239, df = 1, and p-value = 0.0004681) on normalized foliar deposition, with higher values obtained using the fixed spraying system. In addition, a simulation of the spatial distribution based on the principle of inverse distance weighting (IDW) was performed for qualitative spray assessment, confirming the heterogeneity of foliar deposition over the greenhouse with both of the used equipment. In addition, losses to the ground were affected by both spraying equipment and captor position. Full article
(This article belongs to the Section Crop Protection, Diseases, Pests and Weeds)
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6 pages, 1247 KB  
Case Report
Left Coronary Artery—Right Ventricle Fistula Case Report: Optimal Treatment Decision
by Stefan Veljković, Ana Peruničić, Jovana Lakčević, Armin Šljivo, Dragana Radoičić, Mihajlo Farkić, Darko Boljević, Jelena Kljajević, Milovan Bojić and Aleksandra Nikolić
Medicina 2025, 61(1), 56; https://doi.org/10.3390/medicina61010056 - 2 Jan 2025
Cited by 1 | Viewed by 1542
Abstract
Coronary artery fistulas (CAFs) are rare congenital anomalies, presenting in 0.05–0.9% of cases, characterized by an aberrant connection between a coronary artery and a cardiac chamber or great vessel. Clinical manifestations can include heart failure, myocardial ischemia due to coronary steal, arrhythmias, or [...] Read more.
Coronary artery fistulas (CAFs) are rare congenital anomalies, presenting in 0.05–0.9% of cases, characterized by an aberrant connection between a coronary artery and a cardiac chamber or great vessel. Clinical manifestations can include heart failure, myocardial ischemia due to coronary steal, arrhythmias, or infective endocarditis. We report a case of a 39-year-old man initially evaluated in 2016 for peripheral edema and suspected right ventricular (RV) abnormality. Earlier assessments indicated a left anterior descending (LAD) coronary artery–RV fistula, but initial catheterization was nondiagnostic. Transthoracic echocardiography (TTE) revealed a dilated left coronary artery (LCA) and an RV apex aneurysm, confirmed by CT and coronary angiography, showing a 14 mm LAD fistula with large aneurysmal sacs (45.6 × 37.3 mm). Cardiac MRI demonstrated a tortuous LAD fistula draining into RV aneurysmal sacs with preserved biventricular function. Surgical intervention was recommended, but the patient declined and was lost to follow-up until 2022, being asymptomatic. Re-evaluation showed progression in aneurysm size (47 × 45 mm and 16 × 18 mm) without ventricular functional change. Follow-up TTE in 2023 indicated stable findings. This case emphasizes the necessity of multimodal imaging (TTE, CT, MRI, angiography) for CAF diagnosis and management planning. Given the variability in CAF presentation and outcomes, individualized management—including surgical, percutaneous, or conservative strategies—is crucial. Persistent follow-up is essential for monitoring potential complications and guiding treatment, even in asymptomatic patients refusing intervention. Full article
(This article belongs to the Section Cardiology)
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7 pages, 2780 KB  
Case Report
Coronal Cementum and Reduced Enamel Epithelium on Occlusal Surface of Impacted Wisdom Tooth in a Human
by Naohiro Horie, Masaru Murata, Yasuhito Minamida, Hiroki Nagayasu, Tsuyoshi Shimo, Toshiyuki Akazawa, Hidetsugu Tsujigiwa, Youssef Haikel and Hitoshi Nagatsuka
Dent. J. 2024, 12(11), 348; https://doi.org/10.3390/dj12110348 - 30 Oct 2024
Viewed by 1931
Abstract
Background: There is only limited research on the coronal cementum of a tooth, and the mechanisms of its forming process are not well-defined. This report presents a coronal cementum on the occlusal surfaces of enamel in an impacted wisdom tooth in a human, [...] Read more.
Background: There is only limited research on the coronal cementum of a tooth, and the mechanisms of its forming process are not well-defined. This report presents a coronal cementum on the occlusal surfaces of enamel in an impacted wisdom tooth in a human, which is not nearly the cervical portion. Materials and Methods: The tooth (Tooth #1) was derived from a 46-year-old female. Histological analysis, including hematoxylin and eosin (HE) and toluidine blue (TB) staining, and Scanning Electron Microscopy and Energy Dispersive X-ray Spectrometer (SEM-EDS) analysis of the extracted tooth were conducted. Radiographic examination showed that Tooth #1 was horizontally impacted in the maxilla and had the apex of a single root placed between the buccal and palatal roots of Tooth #2. Results: Coronal cementum was distributed widely on the enamel, and reduced enamel epithelium was also found with enamel matrix proteins histologically. The formation of acellular cementum was observed to be more predominant than that of the cellular cementum in Tooth #1. SEM showed that the occlusal cementum connected directly with enamel. Calcium mapping revealed an almost similar occlusal cementum and enamel. In addition, the spectrum of elements in coronal cementum resembled the primary cementum according to SEM-EDS. Discussion: Thus, coronal cementogenesis in impacted human teeth might be related to the existence of reduced enamel epithelium. Full article
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32 pages, 17401 KB  
Article
Unmanned Aerial Vehicle Obstacle Avoidance Based Custom Elliptic Domain
by Yong Liao, Yuxin Wu, Shichang Zhao and Dan Zhang
Drones 2024, 8(8), 397; https://doi.org/10.3390/drones8080397 - 15 Aug 2024
Cited by 5 | Viewed by 3322
Abstract
The velocity obstacles (VO) method is widely employed in real-time obstacle avoidance research for UAVs due to its succinct mathematical foundation and rapid, dynamic planning abilities. Traditionally, VO assumes a circle protection domain with a fixed radius, leading to issues such as excessive [...] Read more.
The velocity obstacles (VO) method is widely employed in real-time obstacle avoidance research for UAVs due to its succinct mathematical foundation and rapid, dynamic planning abilities. Traditionally, VO assumes a circle protection domain with a fixed radius, leading to issues such as excessive conservatism of obstacle avoidance areas, longer detour paths, and unnecessary avoidance angles. To overcome these challenges, this paper firstly reviews the fundamentals and pre-existing defects of the VO methodology. Next, we explore a scenario involving UAVs in head-on conflicts and introduce an elliptic velocity obstacle method tailored to the UAV’s current flight state. This method connects the protection domain size directly to the UAV’s flight state, transitioning from the conventional circle domain to a more efficient elliptic domain. Additionally, to manage the computational demands of Minkowski sums and velocity obstacle cones, an approximation algorithm for discretizing elliptic boundary points is introduced. A strategy to mitigate unilateral velocity oscillation had is developed. Comparative validation simulations in MATLAB R2022a confirm that, based on the experimental results for the first 10 s, the apex angle of the velocity obstacle cone for the elliptical domain is, on average, reduced by 0.1733 radians compared to the circular domain per unit simulation time interval, saving an airspace area of 13,292 square meters and reducing the detour distance by 14.92 m throughout the obstacle avoidance process, facilitating navigation in crowded situations and improving airspace utilization. Full article
(This article belongs to the Special Issue Path Planning, Trajectory Tracking and Guidance for UAVs)
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18 pages, 5911 KB  
Article
Simulating Two-Phase Seepage in Undisturbed Soil Based on Lattice Boltzmann Method and X-ray Computed Tomography Images
by Zhenliang Jiang, Yiqian Lin, Xian Chen, Shanghui Li, Peichen Cai and Yun Que
Sensors 2024, 24(13), 4156; https://doi.org/10.3390/s24134156 - 26 Jun 2024
Cited by 2 | Viewed by 1958
Abstract
The two-phase seepage fluid (i.e., air and water) behaviors in undisturbed granite residual soil (U-GRS) have not been comprehensively studied due to a lack of accurate and representative models of its internal pore structure. By leveraging X-ray computed tomography (CT) along with the [...] Read more.
The two-phase seepage fluid (i.e., air and water) behaviors in undisturbed granite residual soil (U-GRS) have not been comprehensively studied due to a lack of accurate and representative models of its internal pore structure. By leveraging X-ray computed tomography (CT) along with the lattice Boltzmann method (LBM) enhanced by the Shan–Chen model, this study simulates the impact of internal pore characteristics of U-GRS on the water–gas two-phase seepage flow behaviors. Our findings reveal that the fluid demonstrates a preference for larger and straighter channels for seepage, and as seepage progresses, the volume fraction of the water/gas phases exhibits an initial increase/decrease trend, eventually stabilizing. The results show the dependence of two-phase seepage velocity on porosity, while the local seepage velocity is influenced by the distribution and complexity of the pore structure. This emphasizes the need to consider pore distribution and connectivity when studying two-phase flow in undisturbed soil. It is observed that the residual gas phase persists within the pore space, primarily localized at the pore margins and dead spaces. Furthermore, the study identifies that hydrophobic walls repel adjacent fluids, thereby accelerating fluid movement, whereas hydrophilic walls attract fluids, inducing a viscous effect that decelerates fluid flow. Consequently, the two-phase flow rate is found to increase with then-enhanced hydrophobicity. The apex of the water-phase volume fraction is observed under hydrophobic wall conditions, reaching up to 96.40%, with the residual gas-phase constituting 3.60%. The hydrophilic wall retains more residual gas-phase volume fraction than the neutral wall, followed by the hydrophobic wall. Conclusively, the investigations using X-ray CT and LBM demonstrate that the pore structure characteristics and the wettability of the pore walls significantly influence the two-phase seepage process. Full article
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15 pages, 844 KB  
Review
The Recolonisation of the Piketberg Leopard Population: A Model for Human–Wildlife Coexistence in a Changing Landscape
by Jeannine McManus, Albertus J. Smit, Lauriane Faraut, Vanessa Couldridge, Jaco van Deventer, Igshaan Samuels, Carolyn Devens and Bool Smuts
Conservation 2024, 4(2), 273-287; https://doi.org/10.3390/conservation4020018 - 21 May 2024
Cited by 1 | Viewed by 6699
Abstract
Important metapopulation dynamics are disrupted by factors such as habitat loss, climate change, and human-induced mortality, culminating in isolated wildlife populations and threatening species survival. Source populations, where birth rates exceed mortality and connectivity facilitates dispersal, contrast with sink populations, where mortality outstrips [...] Read more.
Important metapopulation dynamics are disrupted by factors such as habitat loss, climate change, and human-induced mortality, culminating in isolated wildlife populations and threatening species survival. Source populations, where birth rates exceed mortality and connectivity facilitates dispersal, contrast with sink populations, where mortality outstrips births, risking localised extinction. Recolonisation by individuals from source populations is pivotal for species survival. The leopard is the last free-roaming apex predator in South Africa and plays an important ecological role. In the Eastern and Western Cape provinces in South Africa, leopard populations have low densities and fragmented population structures. We identified a leopard population that, after being locally extinct for a century, appeared to recolonise an ‘island’ of mountainous habitat. We aimed to understand potential factors driving this recolonisation using recent camera trapping surveys and historical statutory destruction permits. We employed spatially explicit capture–recapture (SECR) methods to estimate the leopard density and explore potential factors which best explain density. We found that the recently recolonised Piketberg population now exhibits some of the highest densities reported in the region (~1.8 leopards/100 km2; CI 1.4–2.5). Livestock, human presence, elevation, and the camera trap grid appeared to explain leopard detection rates. When considering the historic data, the re-emergence of leopards in the Piketberg coincided with the cessation of the extensive state-sponsored and state-enabled culling of the species, and the change in land use from livestock production to crop agriculture, which likely contributed to the recolonisation. Elucidating these factors deepens our understanding of leopard metapopulation dynamics in relation to land use and species management and highlights the crucial role of private land and state agencies and associated policies in species persistence. Full article
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16 pages, 5856 KB  
Article
Radiological Classification and Management Algorithm of Petrous Apex Cholesterol Granuloma
by Daniele Marchioni, Chiara Alberti, Nicola Bisi and Alessia Rubini
J. Clin. Med. 2024, 13(9), 2505; https://doi.org/10.3390/jcm13092505 - 24 Apr 2024
Viewed by 3774
Abstract
Background: Petrous apex cholesterol granulomas (PACGs) are benign inflammatory cystic lesions of the temporal bone. Usually, asymptomatic patients may develop symptoms as the lesions expand. The diagnosis is based on both CT and MRI scans and the management relies on “wait and [...] Read more.
Background: Petrous apex cholesterol granulomas (PACGs) are benign inflammatory cystic lesions of the temporal bone. Usually, asymptomatic patients may develop symptoms as the lesions expand. The diagnosis is based on both CT and MRI scans and the management relies on “wait and scan” or surgery. This paper aims at evaluating surgical outcomes and proposing a CT-based classification and a management algorithm. Methods: Patients with PACGs who were surgically treated between 2014 and 2024 were included. Symptoms, imaging, approach type and complications were considered. CT scans were classified as Type A (preserved apex cellularity), Type B (erosion of the apex cellularity), and Type C (involvement of the noble structures bone boundaries). The possible connection of the lesion with the infracochlear, perilabyrinthine and sphenoidal cellularity was assessed. Results: Nineteen patients with symptoms like diplopia, headache and sensorineural hearing loss were included. According to our classification, 1/19 patients was Type A, 4/19 were Type B and 14/19 were Type C. Five patients underwent a total resection, seven a subtotal and seven a surgical drainage. Only two complications were recorded, and 17/19 patients showed symptom regression and stability during follow-up. Conclusions: While the management of PACGs is still controversial, according to our classification and surgical outcomes, Type A, being mostly asymptomatic, should be managed with “wait and scan”, Type B should undergo surgery when symptoms are present, while Type C should always undergo surgery because of their invasiveness and potential complications. When possible, a drainage should be attempted; otherwise, a surgical resection is chosen, and its completeness depends on the preoperative general and hearing status. Full article
(This article belongs to the Special Issue State of the Art—Treatment of Skull Base Diseases (Second Edition))
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Article
One New Genus and Four New Species of Beaded Lacewings (Neuroptera: Berothidae) from Upper Cretaceous Myanmar Amber
by Yuting Chen, Zihao Peng, Siting Liu, Chaofan Shi, Dong Ren and Qiang Yang
Insects 2024, 15(4), 259; https://doi.org/10.3390/insects15040259 - 9 Apr 2024
Cited by 5 | Viewed by 2254
Abstract
In recent years, as more and more fossil species of berothids from Myanmar have been reported, the species and morphological diversity of Berothidae continues to increase. Herein, one new species of Berothidae, Aggregataberotha paucipunctata sp. nov., and one new genus, Sejunctaberotha gen. nov., [...] Read more.
In recent years, as more and more fossil species of berothids from Myanmar have been reported, the species and morphological diversity of Berothidae continues to increase. Herein, one new species of Berothidae, Aggregataberotha paucipunctata sp. nov., and one new genus, Sejunctaberotha gen. nov., with three new species (Sejunctaberotha sphaerica gen. et sp. nov., Sejunctaberotha tenuis gen. et sp. nov. and Sejunctaberotha transversa gen. et sp. nov.) are described from mid-Cretaceous Myanmar amber. A. paucipunctata sp. nov. is assigned to Aggregataberotha Wang, Huang & Wang, 2022, based on the characteristics of the similar female terminalia and wing venation, but can be different from A. punctate regarding the pale pterostigma and a few detailed features of wing venation. Additionally, representatives of Sejunctaberotha gen. nov. are remarkably different from the representatives of the other genera within Berothidae in the configuration of wing venation. For example, Sejunctaberotha gen. nov. has simple subcostal veinlets, obviously free Sc and RA at the apex present both in fore- and hindwings, a single ra-rp crossvein connecting the RA with RP3, a single rp-m crossvein locating before the origin of the MP, a simple CuP and no gradate veins. Interestingly, in one of the specimens of Sejunctaberotha gen. nov., a pair of spherical bulges was found at the end of the antennae. The new genus Sejunctaberotha gen. nov. suggests that Berothidae had a higher potential diversification during the Mesozoic Era. Full article
(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)
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