Search Results (1,387)

Introduction: This manuscript addresses the limitations of traditional orthognathic surgery in achieving both functional and aesthetic correction in patients with Class II malocclusion and severe mandibular retrusion. Current techniques often struggle to simultaneously address mandibular deficiency and inadequate transverse dimension, leading to unsatisfactory outcomes. Methods: Seven male patients underwent bimaxillary osteotomy with mandibular advancement. A novel surgical plate, Implate, was used, which was designed to facilitate precise osteotomy and stabilization. Pre-surgical planning included CBCT scanning, 3D modeling, and surgical simulation. Postoperative assessments included clinical examinations, CT and OPT scans. Results: Implate successfully addressed the challenges of conventional techniques, minimizing the formation of bony steps and achieving a more harmonious facial profile. The minimally invasive procedure, with careful periosteal and muscle management, contributed to stable outcomes, and no complications were reported. At the 6-month follow-up, OPT analysis showed a mean mandibular width increase of 18.1 ± 6.2 mm and vertical ramus height gains of 6.0 ± 3.1 mm (left) and 5.8 ± 1.7 mm (right). Conclusions: According to our preliminary experience, the integration of Implate into surgical practice offers a significant improvement in treating complex Class II malocclusions. By simultaneously correcting mandibular retrusion and width while minimizing complications, Implate provides a superior solution compared to traditional methods. This innovative approach highlights the potential of combining advanced surgical techniques with personalized 3D-printed implants to achieve optimal functional and aesthetic outcomes. Further prospective studies with controls and longer follow-up are needed to validate the efficacy and reproducibility of Implate in wider clinical use. Full article

Linear passive electrical devices/components are usually characterized in the frequency domain by their impedance, i.e., the ratio of the voltage and current phasors. The use of the impedance concept does not raise particular concerns in low-frequency regimes; however, things become more complicated when it comes to rapid time-varying phenomena, mainly because the voltage depends not only on the position of the points between which it is defined but also on the choice of the integration path that connects them. In this article, based on first principles (Maxwell equations and Poynting vector flow considerations), we discuss the concept of impedance and define it unequivocally for a class of electrical devices/components with rotational symmetry. Two application examples are presented and discussed. One simple example concerns the per-unit-length impedance of a homogeneous cylindrical wire subject to the skin effect. The other, which is more elaborate, concerns a heterogeneous structure that consists of a dielectric disk sandwiched between two metal plates. For the lossless situation, the high-frequency impedance of this device (circular parallel plate capacitor) reaches zero when the frequency reaches a certain critical frequency f_c; then, it becomes inductive and increases enormously when the frequency reaches another critical frequency at 1.6 f_c. The influence of losses on the impedance of the device is thoroughly investigated and evaluated. Impedance corrections due to dielectric losses are analyzed using a frequency-dependent Debye permittivity model. The impedance corrections due to plate losses are analyzed by considering radial current distributions on the outer and inner surfaces of the plates, the latter exhibiting significant variations near the critical frequencies of the device. Full article

To achieve robust and accurate collaborative 3D measurement under complex noise conditions, a global calibration method for dual-arm hand–eye systems and multi-view 3D imaging is proposed. A multi-view 3D scanning approach based on ICP (M3DHE-ICP) integrates a multi-frequency heterodyne coding phase solution with ICP optimization, effectively correcting stitching errors caused by robotic arm attitude drift. After correction, the average 3D imaging error is 0.082 mm, reduced by 0.330 mm. A global calibration method based on encoded marker points (GCM-DHE) is also introduced. By leveraging spatial geometry constraints and a dynamic tracking model of marker points, the transformation between multi-coordinate systems of the dual arms is robustly solved. This reduces the average imaging error to 0.100 mm, 0.456 mm lower than that of traditional circular calibration plate methods. In actual engineering measurements, the average error for scanning a vehicle’s front mudguard is 0.085 mm, with a standard deviation of 0.018 mm. These methods demonstrate significant value for intelligent manufacturing and multi-robot collaborative measurement. Full article

This paper reviews the applications and performance advantages of ultra-high-performance concrete (UHPC), engineered cementitious composite (ECC), and recycled aggregate concrete (RAC) in composite flexural members. UHPC is characterized by its ultra-high strength, high toughness, excellent durability, and microcrack self-healing capability, albeit with high costs and complex production processes. ECC demonstrates superior tensile, flexural, and compressive strength and durability, yet it exhibits a lower elastic modulus and greater drying shrinkage strain. RAC, as an eco-friendly concrete, offers cost-effectiveness and environmental benefits, although it poses certain performance challenges. The focus of this review is on how to enhance the load-bearing capacity of composite beams or slabs by modifying the interface roughness, adjusting the thickness of the ECC or UHPC layer, and altering the cross-sectional form. The integration of diverse concrete materials improves the performance of beam and slab elements while managing costs. For instance, increasing the thickness of the UHPC or ECC layer typically enhances the load-bearing capacity of composite beams or plates by approximately 10% to 40%. Increasing the roughness of the interface can significantly improve the interfacial bond strength and further augment the ultimate load-bearing capacity of composite components. Moreover, the optimized design of material mix proportions and cross-sectional shapes can also contribute to enhancing the load-bearing capacity, crack resistance, and ductility of composite components. Nevertheless, challenges persist in engineering applications, such as the scarcity of long-term monitoring data on durability, fatigue performance, and creep effects. Additionally, existing design codes inadequately address the nonlinear behavior of multi-material composite structures, necessitating further refinement of design theories. Full article

Due to the complexity of modeling tumor-host interactions within the tumor microenvironment in vitro, we developed a 3D heterotypic cellular breast cancer (BC) model. We generated spheroid models using MCF7, MDA-MB-231, and SK-BR-3 cell lines alongside cancer-associated (BrC4f) and normal (BN120f) fibroblasts in ultra-low attachment plates. Stromal spheroids (3Df) were formed using a liquid overlay technique (graphical abstract). The YT cell line and peripheral blood NK (PB-NK) cells were used as immune components in our 3D model. In this study, we showed that stromal cells promoted tumor cell aggregation into spheroids, regardless of the initial proliferation rates, with NK cells accumulating in fibroblast-rich regions. The presence of CAFs within the model induced alterations in the expression levels of MICA/B and PD-L1 by tumor cells within the 3D-2 model. The feasibility of utilizing a 3D cell BC model in combination with cytokines and PB-NKs was evaluated. We observed that IL-15 and IL-2 enhanced NK cell activity within spheroids, whereas TGFβ had varying effects on proliferation depending on the cell type. Stimulation with IL-2 and IL-15 or TGFβ1 altered PB-NK markers and stimulated their differentiation into ILC1-like cells in 3D models. These findings underscore the regulatory function of CAFs in shaping the response of the tumor microenvironment to immunotherapeutic interventions. Full article

Tectonic activity in the Mediterranean region has been driven by the convergence of the confining plates (Nubia, Arabia and Eurasia). This convergence has been accommodated by the consumption of the oceanic domains that were present in the late Oligocene. It is suggested that this process has been enabled by the lateral escape of orogenic belts in response to constrictional contexts. Where this condition was not present, subduction did not occur. This interpretation can plausibly and coherently account for the very complex pattern of tectonic processes in the whole area since the early Miocene. It is also suggested, by providing some examples, that the geodynamic context proposed here might help us to recognize the connection between the ongoing tectonic processes and the spatio-temporal distribution of past major earthquakes. A discussion is then reported about the incompatibilities of the main alternative geodynamic interpretation (slab pull) with the observed deformation pattern. Full article

The electroosmotic flow (EOF) of non-Newtonian fluids plays a significant role in microfluidic systems. The EOF of Powell–Eyring fluid within a parallel-plate microchannel, under the influence of both electric field and pressure gradient, is investigated. Navier’s boundary condition is adopted. The velocity distribution’s approximate solution is derived via the homotopy perturbation technique (HPM). Optimized initial guesses enable accurate second-order approximations, dramatically lowering computational complexity. The numerical solution is acquired via the modified spectral local linearization method (SLLM), exhibiting both high accuracy and computational efficiency. Visualizations reveal how the pressure gradient/electric field, the electric double layer (EDL) width, and slip length affect velocity. The ratio of pressure gradient to electric field exhibits a nonlinear modulating effect on the velocity. The EDL is a nanoscale charge layer at solid–liquid interfaces. A thinner EDL thickness diminishes the slip flow phenomenon. The shear-thinning characteristics of the Powell–Eyring fluid are particularly pronounced in the central region under high pressure gradients and in the boundary layer region when wall slip is present. These findings establish a theoretical base for the development of microfluidic devices and the improvement of pharmaceutical carrier strategies. Full article

The Eastern Carpathians are thrust to the east and north over their Eastern European foreland, tectonically covering it over an area several hundred kilometers across. Information about the nature of the underthrust part of the Carpathian foreland can be obtained from the rock fragments preserved in the sedimentary successions of the Carpathian fold and thrust belt, specifically in the Outer Dacides and the Moldavides. Fragments of felsic rocks occurring within the sedimentary units of the Upper Cretaceous successions of the Moldavides have long been attributed to the Cuman Cordillera—an intrabasinal ridge in the Eastern Outer Carpathians. This work is the first complex geochemical and geochronological study on the exotic igneous clasts of the Cuman Cordillera. Igneous clasts from the southern part of the Moldavides (Variegated clay nappe/formation) are investigated here. They include mainly granites and rhyolites. Phaneritic rocks are composed of cumulus plagioclase, albite, amphibole and biotite, and intercumulus quartz and potassium feldspar, with apatite, magnetite, sphene, and zircon as main accessories, while the porphyritic rocks have a mineral assemblage similar to that mentioned above, displayed in a porphyritic texture with a usually crystallized groundmass. SHRIMP U-Pb zircon dating indicated the 583–597 Ma age interval for magma crystallization. Based on calcareous nannofossils, the depositional age of the investigated igneous clasts is Cenomanian to Maastrichtian, implying that the Cuman Cordillera was an emerged piece of land, herein an active source of sediments in the flysch basin for at least 40 Ma, from the Early Cretaceous (Aptian) to the Late Cretaceous (Maastrichtian). The intrusive and subvolcanic rocks show similar trends for trace and major elements, evincing their comagmatic nature. The enrichment in LILE and LREE relative to HFSE and HREE, as well as the element anomalies (e.g., negative Nb, Ta, and Eu and positive Rb, Ba, K, and Pb) suggest a convergent continental plate margin tectonic setting. Mineral chemistry suggests magma crystallization in relatively oxic conditions (magnetite series), during ascent within a depth of 15 km to 5 km. The igneous rocks attributed to the Cuman ridge display compositional and geochronological features similar to Brno and Thaya batholiths in the Brunovistulian terrane, which could be a piece of the Carpathian foreland not covered by the Tertiary thrusts. Our data confirm the non-Carpathian origin of the igneous clasts, revealing a Neoproterozoic history of the Carpathian foreland units, which include a Cadomian/Pan-African continental arc, exposed mainly during the Late Cretaceous as an intrabasinal island of the Alpine Tethys, traditionally known as the Cuman Cordillera. Full article

Introduction: Monteggia fractures, first described by Giovanni Battista Monteggia, involve a fracture of the proximal ulna with anterior dislocation of the radial head. Bado’s 1967 classification divides these injuries into four types. Rare mixed patterns exist, overlapping with other forearm injuries such as Galeazzi and Essex–Lopresti lesions. These complex fractures/dislocations pose significant diagnostic and therapeutic challenges and are not adequately represented in current classification systems. Methods and Case Presentation: We report the case of a 56-year-old woman with a complex forearm injury sustained from a fall, presenting with radial head fracture/dislocation, mid-shaft radial fracture, distal ulna fracture, and ulnar collateral ligament rupture. Intraoperative imaging confirmed DRUJ stability and partial interosseous membrane disruption. Surgical management included radial head prosthesis implantation, radial shaft fixation with an anatomical locking plate, intramedullary nailing of the distal ulna, and ligament reconstruction. At two-year follow-up, the patient demonstrated full recovery of elbow flexion–extension and satisfactory forearm function. A narrative literature review was also conducted, focusing on hybrid injury variants. Results: Intraoperative examination under anesthesia revealed good elbow stability with 130° flexion, 15° extension lag, and forearm pronation/supination of 70°/60°. An initial Mayo Elbow Performance Score (MEPS) of 65 was recorded, limited by range of motion and stability. Pain during passive mobilization was mild, with a Visual Analogue Scale (VAS) score of 3/10. Postoperative recovery included 15 days of immobilization followed by structured rehabilitation. At two years, the patient regained full elbow flexion–extension but had residual deficits in pronation–supination, attributed to pre-existing conditions. Conclusions: This case illustrates a previously unreported hybrid Monteggia variant, combining features of Monteggia, Galeazzi, and Essex–Lopresti injuries. It highlights the limitations of current classification systems and supports the need for an expanded diagnostic framework. Successful management required a multidisciplinary surgical approach tailored to the injury’s complexity. Further studies are warranted to refine classification and treatment strategies for these rare combined injuries. Full article

The sandwich plates in consideration are structures composed of a number of Lévy plate components laminated with viscoelastic layers, and they are seen in broad engineering applications. In vibration analysis of a sandwich plate, conventional analytical methods are limited due to the complexity of the geometric and material properties of the structure, and consequently, numerical methods are commonly used. In this paper, an innovative analytical method is proposed for vibration analysis of sandwich Lévy plates having different configurations of viscoelastic layers and using various models of viscoelastic materials. The focus of the investigation is on the determination of closed-form frequency response at any given frequencies. In the development, an s-domain state-space formulation is established by the Distributed Transfer Function Method (DTFM). With this formulation, closed-form analytical solutions of the frequency response problem of sandwich plates are obtained, without the need for spatial discretization. As one unique feature, the DTFM-based approach has consistent formulas and unified solution procedures by which analytical solutions at both low and high frequencies are obtained. The accuracy, efficiency, and versatility of the proposed analytical method are demonstrated in three numerical examples, where the DTFM-based analysis is compared with the finite element method and certain existing analytical solutions. Full article

Urban soils are subject to intense anthropogenic disturbance, often resulting in biodiversity loss and reduced ecosystem functionality. However, rhizospheric microbial communities help maintain critical soil-ecosystem services, supporting urban soil resilience. This study evaluated the diversity of culturable bacteria associated with the rhizospheres of Pennisetum clandestinum and Pseudelephantopus spicatus in green areas of Medellín, Colombia, under contrasting levels of anthropic pressures. Rhizospheric and non-rhizospheric soils were sampled near automotive mechanic sites, and bacterial communities were assessed through plate counting and morphological characterization. Alpha, beta, and rarefaction diversity indices were applied to evaluate culturable morphotypes. P. clandestinum supported a more diverse and complex rhizospheric microbiome, particularly in non-exposed soils, while P. spicatus hosted less diverse communities under similar conditions. Diversity indices effectively distinguished microbial patterns, demonstrating the utility of culture-based methods for microbial community assessment. As a first step in microbial bioprospecting workflows, these methods allow for the rapid screening of culturable diversity and support decision-making for the selection of promising environments, plant species, and microbial isolates. This approach can inform urban soil threats, the promotion of beneficial plant–microbe interactions, and the identification of bioindicator species for soil health monitoring in a framework for the management of green areas. Full article

The carbon metabolism activity of rhizosphere soil microbial communities is an essential indicator for assessing soil ecosystem health, as it directly affects soil nutrient cycling and the stability of organic matter. However, there is a limited understanding of the carbon metabolism characteristics of rhizosphere soil microorganisms in alfalfa (Medicago sativa L.) of different ages and their relationships with soil physicochemical properties. This study used Biolog EcoPlates to evaluate the carbon metabolism activity, functional diversity, and carbon-source utilization preferences of rhizosphere soil microbial communities in 5-, 7-, and 9-year-old alfalfa grasslands on the semi-arid Loess Plateau of western China. We analyzed the relationships between soil physicochemical properties and microbial carbon metabolism characteristics, considering their potential covariation. The results showed that, with the extension of alfalfa planting years, the rhizosphere soil water content decreased significantly, pH decreased slightly, but soil organic carbon, total nitrogen, and total phosphorus contents increased significantly. The rhizosphere soil microbial community of 9-year-old alfalfa exhibited the highest carbon metabolism activity, Shannon diversity index, and carbon-source utilization. Rhizosphere soil microorganisms from different-aged alfalfa showed significantly different preferences for carbon-source utilization, with microorganisms from 9-year-old alfalfa preferentially utilizing carbon sources such as N-acetyl-D-glucosamine, D-mannitol, and D-cellobiose. Redundancy analysis revealed that soil water content was among the most important factors influencing the carbon metabolism activity of rhizosphere soil microbial communities while acknowledging that the relative contributions of soil water content, organic carbon, and nitrogen require careful interpretation, owing to their potential collinearity. This study demonstrates that, under rain-fed conditions in the semi-arid Loess Plateau, the continuous cultivation of alfalfa for nine years led to a significant decrease in soil water content but enhanced the rhizosphere soil nutrient status and microbial carbon metabolism activity, with no apparent signs of microbial functional degradation, although soil water depletion was observed. These findings highlight the complex interactions among multiple soil factors in influencing microbial carbon metabolism, providing valuable microbiological insights for understanding the sustainability of alfalfa grasslands and a theoretical basis for the scientific management of alfalfa grasslands in the semi-arid Loess Plateau region. Future research should consider longer planting periods to determine the critical age of alfalfa grassland degradation under semi-arid conditions and its associated microbial mechanisms. Full article

To address the challenges in ship plate detection under complex maritime scenarios—such as small target size, extreme aspect ratios, dense arrangements, and multi-angle rotations—this paper proposes a multi-module collaborative detection algorithm, RT-DETR-HPA, based on an enhanced RT-DETR framework. The proposed model integrates three core components: an improved High-Frequency Enhanced Residual Block (HFERB) embedded in the backbone to strengthen multi-scale high-frequency feature fusion, with deformable convolution added to handle occlusion and deformation; a Pinwheel-shaped Convolution (PConv) module employing multi-directional convolution kernels to achieve rotation-adaptive local detail extraction and accurately capture plate edges and character features; and an Adaptive Sparse Self-Attention (ASSA) mechanism incorporated into the encoder to automatically focus on key regions while suppressing complex background interference, thereby enhancing feature discriminability. Comparative experiments conducted on a self-constructed dataset of 20,000 ship plate images show that, compared to the original RT-DETR, RT-DETR-HPA achieves a 3.36% improvement in mAP@50 (up to 97.12%), a 3.23% increase in recall (reaching 94.88%), and maintains real-time detection speed at 40.1 FPS. Compared with mainstream object detection models such as the YOLO series and Faster R-CNN, RT-DETR-HPA demonstrates significant advantages in high-precision localization, adaptability to complex scenarios, and real-time performance. It effectively reduces missed and false detections caused by low resolution, poor lighting, and dense occlusion, providing a robust and high-accuracy solution for intelligent ship supervision. Future work will focus on lightweight model design and dynamic resolution adaptation to enhance its applicability on mobile maritime surveillance platforms. Full article

Many ship panels may be subjected to operational or accidental impact loads, and increased crashworthiness is a desirable design feature. A designer may reach this goal using different structural configurations that are available nowadays. However, the selection of the appropriate design parameters is not simple, due to the complexity of predicting impact response. This research is based on published experimental crashworthiness results of a steel stiffened panel tested under low-velocity impact loading. A series of finite element analyses is performed to develop a master model that can be applied to different parameters. The results showed good agreement between the developed finite element model and the experimental results, which confirms the accuracy and reliability of the numerical model. A parametric study is carried out to investigate the effect of design parameters such as plating thickness, stiffener section modulus, stiffener spacing, and stiffener profiles on the crashworthiness characteristics of the calibrated model, and the geometrical configurations that offer the best crashworthiness without considerable increased weight may be then determined based on a proposed criterion. To cover complex realistic scenarios during operation, pre-existing mechanical damage consisting of a specified dent is applied to the intact panel, to check the survivability of the proposed model with respect to the intact one. Finally, simplified design guidelines are proposed to improve both the safety and structural integrity characteristics of the structural configurations considered. Full article

Background: Displaced proximal humerus fractures (PHFs) in adults represent a common orthopedic challenge, especially in elderly patients with compromised bone quality. Intramedullary nails (IM) and locking plates (LP) are the most widely used fixation techniques, though the literature remains inconclusive regarding their comparative efficacy. Methods: This retrospective cohort study included 187 patients (mean age: 65.4 years) treated surgically for Neer ≥ 2-part proximal humerus fractures at a single tertiary referral center between 2018 and 2023. Patients underwent either IM nailing or LP fixation. Baseline characteristics included age, sex, smoking status, ASA score, trauma mechanism, and bone quality (assessed by the Deltoid Tuberosity Index). Functional outcomes (DASH and Constant–Murley scores), range of motion (ROM), radiographic healing, and complications were evaluated at 1, 3, 6, and 12 months postoperatively. Results were stratified by fracture type (two-, three-, and four-part fractures) and treatment group. Results: At 12 months, no statistically significant differences were found between groups in terms of DASH (p = 0.484) or Constant–Murley scores (p = 0.057). ROM recovery was comparable across all time points. Stratified analysis showed similar outcomes across fracture types. Age, smoking, and bone quality did not significantly influence clinical results. The overall complication rate was 11.8%, with no significant difference between groups. Avascular necrosis and hardware-related issues occurred predominantly in four-part fractures. Conclusions: Both intramedullary nailing and locking plate fixation provided comparable short-term outcomes for displaced PHFs. Functional recovery appeared more dependent on fracture complexity than on the choice of implant. Surgical technique should therefore be selected based on fracture morphology, patient characteristics, and surgeon experience. Full article