Search Results (1,251)

Iron (Fe) is an essential micronutrient for plant development and productivity. Nevertheless, the role of gibberellins (GAs) in the control of iron homeostasis is less studied compared to other growth regulators. We found that GAs modulate iron homeostasis in maize by inducing deficiency-like responses independent of rhizosphere iron availability. Plant phenotyping demonstrated that exogenous GA₃ application under iron-sufficient conditions phenocopied iron deprivation, while inhibiting GA biosynthesis with mepiquat chloride prevented the development of typical symptoms of Fe deficiency (–Fe). Gibberellins positively control strategy II Fe uptake genes, albeit indirectly, as opposed to the direct negative transcriptional regulation of phytosiderophore biosynthesis. Additionally, gibberellins disrupt iron partitioning by suppressing root-to-shoot Fe translocation, causing iron overaccumulation in roots of GA₃ treated plants. A functional ferrous iron uptake pathway was identified and was found to operate in conjunction with the strategy II uptake pathway via the differentially regulated Zea mays Iron-Regulated Transporter (IRT) paralogs ZmIRT1 and ZmIRT2. Root responses are spatially organized: gene expression in the lateral root sector reflects the shoot iron status, while transcriptional responses in the root apex correlate with local Fe demands. This study demonstrates that maize leverages a hybrid ferric/ferrous iron uptake strategy and establishes novel roles of GAs as pivotal regulators of iron homeostasis. Full article

The present work explores the effects of dental splints from a mechanical standpoint, aiming to provide a practical tool for the surgical decision-making process regarding splint cross-section dimensions. Our investigation centers on the anatomical structure of a pentamorphic dental arch encompassing central and lateral incisors and one canine on each side. Using parametric in silico models built up by means of an ad-hoc procedure, geometry, material properties, and boundary conditions are defined on a parametric anatomical model that can be tailored using RX-derived geometrical information. Two general cases have been considered, one with the splint and the other splintless, and a sensitivity analysis has been performed by varying the splint section height and thickness. The results show the diminishing mobility at the apex and basis of the diseased incisors, demonstrating the effectiveness of the periodontal treatment. Moreover, the stress due to physiological loads moves away from diseased teeth toward the healthy ones due to the splint effects, focusing on the splint–glue–canine contact zone and highlighting the crucial role played by the canine in fixing the entire dental structure. To establish a preliminary mechanical assessment of the dental structure’s safety and to confine its actual value within a mechanically reasonable range, a synthetic “traffic-light” indicator of stress-based failure risk is proposed. It is felt that the tool proposed in this study can help surgeons assess the pre-operative patient-specific mechanical effects of the splint treatment, driving the design and choice of periodontal splints. By linking splint geometry to mechanical safety via a stress-based indicator, the method supports the optimized design and selection of splints, improving treatment reliability while preserving comfort and clinical effectiveness. Full article

This study introduces an innovative sensor architecture predicated on surface plasmon polaritons (SPPs), comprising a metal–insulator–metal (MIM) waveguide in conjunction with a cat-faced circular split resonator (TCRSW). The efficacy of the proposed nanosensor was meticulously evaluated utilizing the finite element method (FEM). It was determined that the TCRSW configuration significantly impacts the sensor’s performance. By means of a comprehensive optimization of the structural parameters, the sensor attained an apex sensitivity of 3380 nm/RIU and a figure of merit (FOM) of 56.33 in its optimal configuration. Furthermore, the study comprehensively evaluated the sensor’s applicability for temperature sensing, demonstrating a measured temperature sensitivity of 1.673 nm/°C. Meanwhile, the application of the proposed structure in biosensing was comprehensively evaluated. When employed as a concentration sensor for detecting sodium and potassium ion solutions, the maximum achievable sensitivities reached 0.49 mg·d/L and 0.6375 mg·d/L, respectively, which highlights its significant potential not only for high-precision temperature monitoring but also for sensitive and reliable biosensing applications. Additionally, the proposed nanosensor holds considerable promise for applications in other nanophotonic fields. Full article

Background: Orbital dermoid cysts are common benign lesions; however, deep-seated or recurrent lesions near the orbital apex pose major surgical challenges due to their proximity to critical neurovascular structures. Lateral orbitotomy remains the reference approach, but accurate osteotomies and stable reconstruction can be difficult to achieve using conventional techniques. This study reports our initial experience using a fully digital, hospital-based point-of-care (POC) workflow to enhance precision and safety in complex orbital dermoid cyst surgery. Methods: We present a case series of three patients with orbital dermoid cysts treated at a tertiary center (2024–2025) using a comprehensive digital workflow. Preoperative assessment included CT and/or MRI followed by virtual surgical planning (VSP) with orbit–tumor segmentation and 3D modeling. Cutting guides and patient-specific implants (PSIs) were manufactured in-house under a certified hospital-based POC protocol. Surgical strategies were tailored to each lesion and included piezoelectric osteotomy, intraoperative navigation, intraoperative CT, and structured-light scanning when indicated. Results: Complete en bloc resection was achieved in all cases without capsular rupture or optic nerve injury. Intraoperative CT confirmed complete lesion removal and accurate PSI positioning and fitting. Structured-light scanning enabled radiation-free postoperative monitoring when used. All patients preserved full ocular motility, visual acuity, and facial symmetry, with no complications or recurrences during follow-up. Conclusions: The integration of VSP, in-house POC manufacturing, and image-guided surgery within a lateral orbitotomy approach provides a reproducible and fully integrated workflow. This strategy appears to improve surgical precision and safety while supporting optimal long-term functional and aesthetic outcomes in challenging orbital dermoid cyst cases. Full article

The Apex-Shifted Hyperbolic Radon Transform (ASHRT) is a variant of the Radon Transform. In the field of seismic exploration, it can be applied to simultaneous source separation, diffraction- and reflection-wave separation, seismic data reconstruction, among other purposes. This paper primarily investigates the application of ASHRT in the separation of diffraction and reflection waves. Detailed exploration of complex structures using diffraction wave imaging has become a new trend, thereby necessitating the separation of diffraction wave fields. The conventional ASHRT based on the Stolt operator, due to its weak sparsity, increasingly struggles to meet current separation requirements. Compared to conventional ASHRT, the Stolt-based ASHRT enables fast, efficient computation; however, the Stolt operator exhibits relatively weaker sparseness and fidelity. To address this issue, replacing the Stolt operator with the PS operator for performing ASHRT allows the transform to achieve both high sparseness and high fidelity simultaneously. In this study, synthetic data were used to investigate the advantages of the PS operator over the Stolt operator. Furthermore, both operators were applied to separate diffraction and reflection waves in marine seismic data and land seismic data, respectively. The research demonstrates that, in the separation of diffraction and reflection waves using the ASHRT method, the PS operator provides significant advantages over the Stolt operator in terms of both sparseness and fidelity. Full article

Background/Objectives: This study evaluates the penetration of a calcium silicate-based sealer (BC Universal) into dentinal tubules after different final irrigation protocols. Methods: Eighty-four single-rooted extracted teeth were instrumented with ProTaper Gold to size F4 and assigned to four groups (n = 21) according to the final irrigation protocol as follows: conventional needle irrigation (CNI), sonic agitation with EndoActivator (EA), ultrasonic activation (UA), and XP-Endo Finisher (XPF). A total of 20 canals from each group were filled with BC Universal sealer mixed with fluorescein and the single-cone obturation technique. The remaining specimen in each group served as a negative control to assess potential imaging bias. Specimens were sectioned 3 mm from the apex and analyzed under confocal laser scanning microscopy. Sealer penetration was assessed by penetration area (PA), maximum depth (MaxD), mean depth (MeanD), and percentage of canal perimeter infiltrated (P). Data were analyzed using Kruskal–Wallis or ANOVA tests (α = 0.05). Results: All activation/agitation techniques showed significantly higher penetration than CNI across all variables (p < 0.001). No significant differences were found among EA, PUI, and XPF for PA, MaxD, and MeanD. However, XPF exhibited the highest perimeter infiltration, which was significantly greater than EA and UA (p < 0.001). Conclusions: Irrigant activation significantly enhanced dentinal tubule penetration of BC Universal sealer compared to CNI. XPF provided superior P, suggesting superior circumferential distribution. These findings suggest a more effective cleaning of the root canal in the apical third achieved by the tested irrigant activation/agitation techniques, which may improve the sealing potential of BC Universal sealer. Full article

Background/Objective: Maxillary canine impaction is a frequent orthodontic challenge. Three-dimensional CBCT assessment allows precise evaluation of periradicular bone density, which may play a role in eruption failure. This study aimed to compare bone density (HU) around impacted canines with that of the contralateral erupted tooth and to assess correlations with age and sex. Methods: A total of 26 patients (10 males, 16 females; 13–19 years) with unilateral maxillary canine impaction were examined. Pre-treatment CBCT scans acquired were analyzed. Bone density was measured in HU at three root levels (cervical, middle, apical) and in four regions (buccal, palatal, mesial, distal). Statistical analyses included Student’s t-tests, linear regression, and correlation coefficients, with significance set at p < 0.05. Results: Tooth 2.3 was the most frequently impacted (61.5%), with a slight predominance of palatal impactions (53.8%). Bone density was significantly higher around impacted canines than around the contralateral erupted teeth in all regions and levels (p = 0.000), with values increasing from the cervical portion toward the apex. In impacted canines, bone density increased significantly with age, whereas no meaningful differences were found between males and females. Conclusions: Higher bone density surrounding impacted canines supports its potential role in eruption failure. The age-related increase highlights the clinical importance of early diagnosis and timely orthodontic–surgical intervention. Full article

Background: Adult patients with a thin buccal cortical plate and fragile periodontal phenotype are at high risk of dehiscence, fenestration and recession during transverse orthodontic expansion. Conventional mechanics often create a cervical compression-dominant environment that exceeds the adaptive capacity of the periodontal ligament (PDL)–bone complex. Objectives: This study proposes an integrative mechanobiological model in which a skeletal-anchorage-assisted loading protocol (Bone Protection System, BPS) transforms expansion into a tension-dominant regime that favours buccal phenotype preservation. Methods: Patient-specific finite element models were used to compare conventional expansion with a BPS-modified force system. Regional PDL stress patterns and crown/apex displacement vectors were analysed to distinguish tipping-dominant from translation-dominated mechanics. A pilot CBCT proof-of-concept (n = 1 thin-phenotype adult) with voxel-based registration quantified changes in maxillary and mandibular alveolar ridge width and buccal cortical plate thickness before and after BPS-assisted expansion. The mechanical findings were integrated with current evidence on compression- versus tension-driven inflammatory and osteogenic pathways in the PDL and cortical bone. Results: FEM demonstrated that conventional expansion concentrates high cervical compressive stress along the buccal PDL and cortical surface, accompanied by bending-like crown–root divergence. In contrast, the BPS protocol redirected forces to create a buccal tensile-favourable region and a more parallel crown–apex displacement pattern, indicative of translation-dominated movement. In the proof-of-concept (n = 1) CBCT case, BPS-assisted expansion was associated with preservation or increase of buccal ridge dimensions without radiographic signs of cortical breakdown. Conclusions: A tension-dominant orthodontic loading environment generated by a skeletal-anchorage-assisted force system may support buccal cortical preservation and vestibular phenotype reinforcement in thin-phenotype patients. The proposed mechanobiological model links these imaging and FEM findings to known molecular pathways of inflammation, angiogenesis and osteogenesis. It suggests a functional biomaterial-based strategy for widening the biological envelope of safe tooth movement. Full article

Background/Objectives: Precise implant positioning is critical for successful prosthetic rehabilitation, particularly in completely edentulous patients where anatomical landmarks are lost. The aim of this study was to assess the accuracy of implant placement in the edentulous maxilla and mandible using computer-assisted planning and a bone-supported stackable surgical guide protocol. Methods: This retrospective clinical study included 15 completely edentulous patients who received a total of 60 implants. A dual-scan protocol was utilized for planning. The surgical protocol involved a base guide fixed to the bone with pins, serving as a rigid foundation for stackable components used for osteotomy and implant insertion. Postoperative CBCT scans were superimposed onto the preoperative plan to calculate angular deviations, 3D linear deviations at the implant neck and apex, and depth deviations. Results: The analysis demonstrated high accuracy with a mean angular deviation of 1.25° ± 0.80°. The mean 3D linear deviation was 0.96 ± 0.57 mm at the implant neck and 1.07 ± 0.56 mm at the apex. Depth deviation showed a mean discrepancy of 0.37 ± 0.58 mm. All measured parameters were statistically significantly lower (p < 0.05) than the pre-established clinical safety thresholds. Conclusions: Within the limitations of this study, the bone-supported stackable surgical guide protocol proved to be a highly accurate method for full-arch rehabilitation. By eliminating mucosal resilience and ensuring rigid fixation, this approach enables predictable implant placement and facilitates the passive fit of screw-retained bar-supported prostheses, representing a reliable alternative to dynamic navigation in daily clinical practice. Full article

Brown algae of the Cystoseira genus are recognized as valuable sources of bioactive compounds, including polysaccharides. Within the framework of current restoration efforts regarding damaged Ericaria amentacea populations in the Mediterranean Sea, the valorization of apices derived from ex situ cultivation waste represents a sustainable opportunity for industrial and biomedical applications. In this study, sodium alginate (SA) was extracted from E. amentacea apex by-products using a hydrothermal–alkaline method and subsequently chemically characterized. FTIR analysis showed O-H, C-H, and COO- stretching compatible with commercial alginates, while 1H-NMR spectroscopy indicated high β-D-mannuronic acid content, with an M/G ratio of 2.33. The extracted SA displayed a molecular weight of 1 × 10⁴ g/mol and a polydispersity index of 3.5. The bioactive properties of the SA extract were investigated in chemico and in vitro. SA exhibited remarkable antioxidant activity, showing significant DPPH and nitric oxide-radical-scavenging capacity. Furthermore, SA demonstrated a strong anti-inflammatory effect in LPS-stimulated macrophages through modulation of several inflammatory mediators (i.e., IL-6, IL-8/CXCL5, MCP-1, and TNF-α). In particular, SA promoted a striking iNOS gene expression inhibition, which, paired with its direct NO-scavenging ability, paves the way for future pharmacological use of E. amentacea derivatives, particularly if sustainably obtained from restoration activity waste. Full article

Background/Objectives: Effective removal of organic tissue extruded beyond the apex is crucial in regenerative endodontics, particularly in teeth with immature apices; therefore, this study aims to compare the efficacy of standard needle irrigation (SNI), ultrasonic irrigation (UI), photon-induced photoacoustic streaming (PIPS), and shock wave-enhanced emission photoacoustic streaming (SWEEPS) techniques in dissolving periapical tissue in a simulated model. Methods: Sixty single-rooted human premolars and sixty bovine palatal mucosa specimens were used. A custom model was created by placing mucosal tissue in contact with the apical area. Specimens were divided into four groups (n = 15) according to the irrigation method: SNI, UI, PIPS, and SWEEPS. Each canal received 15 mL of 2% NaOCl. Tissue samples were weighed before and after treatment. One-way ANOVA and Tukey’s post hoc test were used for statistical analysis (p < 0.05). Results: UI showed significantly less tissue dissolution than the other methods (p < 0.05). SNI, PIPS, and SWEEPS showed no significant differences (p > 0.05). Conclusions: All methods led to tissue loss, but UI was significantly less effective. SNI, PIPS, and SWEEPS performed similarly. Full article

Robotic peach harvesting represents a pivotal strategy for reducing labor costs and improving production efficiency. The fundamental prerequisite for a harvesting robot to successfully complete picking tasks is the accurate recognition of fruit growth posture subsequent to target identification. This study proposes a novel methodology for peach growth posture recognition by integrating an enhanced YOLOv8 algorithm with the RTMpose keypoint detection framework. Specifically, the conventional Neck network in YOLOv8 was replaced by an Atrous Feature Pyramid Network (AFPN) to bolster multi-scale feature representation. Additionally, the Soft Non-Maximum Suppression (Soft-NMS) algorithm was implemented to suppress redundant detections. The RTMpose model was further employed to locate critical morphological landmarks, including the stem and apex, to facilitate precise growth posture recognition. Experimental results indicated that the refined YOLOv8 model attained precision, recall, and mean average precision (mAP) of 98.62%, 96.3%, and 98.01%, respectively, surpassing the baseline model by 8.5%, 6.2%, and 3.0%. The overall accuracy for growth posture recognition achieved 89.60%. This integrated approach enables robust peach detection and reliable posture recognition, thereby providing actionable guidance for the end-effector of an autonomous harvesting robot. Full article

Background: The pterygomaxillary region is a complex anatomical area formed by the junction of the maxillary, palatine, and sphenoid bones and contains critical neurovascular structures. Accurate assessment of this region during Le Fort I osteotomy is essential, particularly to prevent hemorrhage and nerve injury that may occur during the pterygomaxillary separation phase. This study aims to investigate the morphometric characteristics of the pterygomaxillary region using cone-beam computed tomography (CBCT) and to evaluate the effects of age, sex, and laterality on these anatomical parameters. Materials and Methods: In this retrospective study, CBCT scans of 200 individuals (100 males and 100 females) aged 20–80 years were analyzed. Axial measurements included distances between the piriform rim, the descending palatine artery, the pterygomaxillary osteotomy line, and the pterygomaxillary fissure. Additionally, the thickness and width of the pterygomaxillary region and pterygoid process, lengths of the medial and lateral pterygoid laminae, and the distance between the greater palatine canal and the medial pterygoid lamina apex were recorded. Measurements were statistically evaluated by sex, age group, and laterality. Results: The following parameters demonstrated statistically significant differences based on the conducted measurements: The distance between the piriform rim and the descending palatine artery was significantly greater on the left side (p < 0.001). The length of the lateral pterygoid lamina increased with advancing age (p = 0.048). The thickness of the pterygomaxillary region was significantly greater in females (p = 0.014). Additionally, the distance between the greater palatine canal and the terminal point of the medial pterygoid lamina was significantly higher in males (p < 0.001). Conclusions: The pterygomaxillary region exhibits anatomical variations that may lead to serious complications during Le Fort I osteotomy. Detailed preoperative evaluation of this area using CBCT can guide surgical planning and help prevent potential vascular and neural complications. Full article

Understanding how carnivores coexist is central to ecological theory and conservation. Coexistence among sympatric species arises through niche partitioning across spatial, temporal, and trophic dimensions, yet these mechanisms remain poorly explored in Central African forests where leopards (Panthera pardus) and African golden cats (Caracal aurata) act as dominant and subordinate carnivores. Using camera trap data and molecular scat analyses from two sites in northern Congo, we provided the first robust leopard density estimates for the region (i.e., semideciduous forests in Central Africa) and assessed coexistence mechanisms between the two felids across spatial, temporal, and trophic axes. Spatially explicit capture–recapture models revealed comparable leopard densities across sites (5–6 individuals/100 km²), exceeding the regional average for Central and East Africa. Spatiotemporal occupancy models indicated spatial and temporal overlap, with no evidence of predictive or reactive temporal avoidance, though fine-scale co-occurrence declined near linear forest features (i.e., main rivers and roads) where both species’ marginal occupancy was highest. Conversely, dietary analyses showed trophic segregation: leopards consumed medium- to large-sized ungulates (>20 kg), whereas golden cats relied on smaller prey (≤5 kg), identifying trophic partitioning as the main axis facilitating coexistence in this prey-rich system. Maintaining prey diversity and minimizing disturbance are key to sustaining both species and their coexistence mechanisms. Such multidimensional approaches are essential to understand intraguild interactions and anticipate community shifts under increasing pressure. Full article

Lethocerus patruelis (Stål, 1854), the sole European belostomatid, is an apex invertebrate predator in Mediterranean freshwater systems and a species known for its strong flight capacity and growing range expansion record. While its continental distribution in Greece is increasingly well documented, its presence across the Aegean islands has remained poorly characterized, with historical records scattered and often unpublished or fragmentary. Here, we present new, photographically verified records that substantially refine the species’ insular distribution and provide the first coordinated synthesis of its emerging archipelagic footprint. These include the first confirmed live individual from Samothraki and a newly documented specimen from Naxos, recovered beside a nearly desiccated summer stream indicating a very recent arrival. When integrated with additional verified observations from Sifnos, Ikaria, Chios, Euboea, Tilos, and Crete, as well as earlier published records, a coherent spatial pattern emerges. Rather than isolated vagrants, the records align along three longitudinal dispersal axes spanning the northern, central, and southern Aegean. These axes reflect plausible biological and anthropogenic pathways influenced by regional winds, maritime transport, and the distribution of natural and artificial freshwater habitats. Collectively, the evidence indicates that L. patruelis is undergoing a sustained, multi-vector archipelagic expansion, underscoring the importance of integrating citizen-science observations with targeted field documentation to monitor freshwater biodiversity across Mediterranean islands. Full article