To evaluate, through three-dimensional finite element analysis (FEA), the stress and strain distribution in reconstruction plates of different thicknesses used for fixation of bone-grafted segmental mandibular defects. A dentate mandibular model was obtained from computed tomography data and digitally processed for FEA using ANSYS 7.0. Three reconstruction plate models (2.0, 2.4, and 3.0 mm thick) were applied to simulate defects in the symphyseal, body, and angle regions of the mandible, each associated with block bone grafts and fixed using 2.4-mm locking screws. A 300-N vertical occlusal load and muscle vectors representing masticatory forces were simulated. Stress distribution was analyzed according to von Mises criteria across plates, screws, and bone graft blocks. Increasing plate thickness reduced stress concentration within the plates but significantly increased stress on the fixation screws, particularly those adjacent to osteotomy lines. The symphyseal defect exhibited the highest stress values, followed by the body and angle defects. Stress values within bone graft blocks remained low (<250 MPa), indicating minimal deformation. Thicker reconstruction plates enhance mechanical resistance but increase stress concentration on fixation screws, especially near osteotomies, suggesting a higher risk of screw loosening or peri‑implant bone resorption. The anterior mandible demonstrated the most unfavorable stress distribution. Locking fixation systems are recommended when rigid plates are used to mitigate screw-related complications.

Traumatic brain injury (TBI) induced by rotational loading is a major contributor to neurological dysfunction, yet the biomechanical mechanisms underlying these injuries remain poorly understood. In this study, a high-resolution, anatomically accurate three-dimensional finite element model of the mouse brain (FEM-MB) was developed. The FEM-MB was validated against previously published experimental data, showing good agreement in both the timing and magnitude of strain responses. The FEM-MB was then subjected to unidirectional and multidirectional rotational loading scenarios at low (100 rad/s), moderate (150 rad/s), and high (200 rad/s) peak angular velocities to investigate the mouse brain's response to multidirectional rotational loading. The FEM-MB results consistently revealed that deep brain regions, particularly the thalamic-hippocampal region, hypothalamus, and brainstem, experienced the highest maximum principal strains. These results highlight that not only the magnitude, but also the direction and temporal asymmetry of rotational loading, significantly affect the strain distribution across brain regions. In particular, the thalamic-hippocampal and brainstem regions had the highest strains under coronal and axial plane rotations, aligning with known injury patterns. These findings underscore the critical role of rotation direction and loading profile on strain magnitude and distribution in the mouse brain under dynamic rotational loading. Overall, the FEM-MB provides a robust in silico platform to investigate the effects of dynamic rotation loading in preclinical models of TBI.

Fatigue cracking in steel structures poses a significant threat to their long-term performance and reduces their fatigue life. This study examines the effect of a repair intervention using ultrahigh-modulus carbon fiber–reinforced polymer (CFRP) bonded plates applied at various stages of fatigue crack propagation and its impact on extending the remaining fatigue life. The study also investigates the effect of CFRP bond length on crack growth rates and strain distributions. Bond lengths ranged from 0.5 to 2.4 times the effective development length (75–350 mm). Machined notches simulated initial defects, and cyclic loading was applied before and after retrofitting to control damage levels. Crack growth rates were quantified using beach marking, while strain concentrations and profiles were measured using distributed fiber optic sensing. The results show that CFRP repair is effective in increasing the fatigue life of a structure. For a CFRP plate with a 225 mm bond length, the remaining fatigue life extension ratio increased from 3.2 when intervention occurred at the onset of crack propagation (i.e., 25% area loss in the notched plate) to 7.2 when intervention occurred late in life, at 95% of the total cycles to failure (59% area loss) of the control samples. However, if assessment is based on increase in total cycles (i.e., pre- plus postrepair), results show a reduction in effectiveness at late intervention.

This study explores the application of long-read sequencing technologies for genotyping, epigenetic profiling, and epidemiological monitoring of Yersinia pestis isolates obtained from natural foci in Central Asia and previous zoonotic outbreaks. Computational tools for genome assembly and genotyping were developed, enabling high-precision identification of both chromosomal and plasmid sequences, including the small plasmid pCKF. Genotyping based on genetic polymorphisms distinguished the major Y. pestis biovars and lineages, and revealed cluster-specific diversity among Medievalis (2.MED) isolates, including groups of strains associated with different plague foci and disease outbreaks in domestic animals and humans. These specific genomic polymorphisms identified in subclades of 2.MED isolates allow their high-precision identification. The distribution of pCKF-positive strains in the region and the potential involvement of these pathogens in disease outbreaks are discussed. Additionally, comparative epigenomic analysis uncovered strain-specific cytosine methylation patterns at cgGATCG motifs. Further studies involving more sequenced strains are needed to determine whether this cytosine methylation specificity is linked to genome function regulation and adaptation to different hosts and environments. These findings demonstrate the effectiveness of long-read sequencing technologies in revealing both genetic and epigenetic features of bacterial pathogens, contributing to our understanding of the evolutionary mechanisms underlying the emergence and spread of this especially dangerous infection.

Genomic characterization and global lineage-plasmid context of a bla NDM-5-harboring Escherichia coli ST3014 isolate.

Local microstrain variation in the compression of bionic bone with fracture fixation.

Molecular epidemiology of Treponema pallidum subsp. pallidum among men who have sex with men at an HIV referral hospital in Tokyo: Multilocus sequence typing and macrolide resistance.

Plasmon resonances arise from the collective oscillations of free electrons in conductive media, enabling strong light-matter interactions. In contrast to semiconductors, the plasmonic response of metals is regarded as intrinsically fixed by their large carrier density and electronic structure and therefore relatively insensitive to external perturbations such as mechanical strain. Here, we show conclusive experimental evidence that plasmon resonances in metals can be actively tuned through strain engineering. Using epitaxial ultrathin titanium nitride (TiN) films, we demonstrate that in-plane tensile strain produces a pronounced blue shift of both unscreened and screened plasmon modes relative to unstrained films of identical thickness, with the magnitude of the shift closely tracking the local strain distribution. First-principles calculations reveal that strain modifies the local defect landscape, which alters the electronic structure, governing the plasmonic response. These results establish strain as an effective control knob for plasmonic properties in metals, enabling mechanically reconfigurable plasmonic and nanophotonic platforms.

Should Inter-Prosthetic Screws Be Placed When Prophylactically Plating a Femur?

In atomically thin membranes, strain couples strongly to electrons, phonons, and photons. Although strain originating from uniform or global deformation has been widely studied, the impact of spatially localized mechanical perturbations on strain distribution remains less explored. Here, we investigate how localized tungsten carbide deposition via focused electron-beam-induced deposition (FEBID) modifies the strain landscape in suspended monolayer graphene membranes. Using spatially resolved mechanical resonance mode shape mapping and Raman spectroscopy, supported by finite element simulations, we find that the central deposit acts as a mechanically coupled local perturbation that redistributes the pre-existing strain into a more radially symmetric configuration with reduced angular anisotropy around the deposit. These findings demonstrate that FEBID-based local deposition can serve as a lithography-free approach for controlled strain modulation in suspended graphene, offering a practical platform for studying strain-coupled phenomena and designing strain-controlled nanoelectromechanical and optoelectronic systems.

Transcatheter edge-to-edge repair (TEER) and annuloplasty devices are increasingly used to treat mitral valve regurgitation, yet their mechanical effects and interactions remain poorly understood. This study aimed to establish an open-source finite element modeling (FEM) framework for simulating patient-specific mitral valve repairs and to evaluate how TEER, annuloplasty, and combined strategies influence leaflet coaptation and valve mechanics. A central objective was to demonstrate how such simulations may support surgical planning by identifying optimal interventions. A patient-specific mitral valve model was reconstructed using SlicerHeart and 3D Slicer. Four G4 MitraClip geometries were modeled and deployed in FEBio to capture leaflet grasp and subsequent clip-leaflet motion under physiologic pressurization. CardioBand annuloplasty was simulated by reducing annular circumference via displacement-controlled boundary conditions, and Mitralign suture annuloplasty was modeled using discrete nodal constraints. Simulations were performed for prolapse and dilated annulus cases, comparing repairs individually and in combination. Valve competence (regurgitant orifice area, ROA), coaptation/contact area (CA), and leaflet stress and strain distributions were quantified. In the prolapse anatomy, the simulations showed that while TEER restored coaptation, it also increased the stresses on the leaflets, whereas band and suture annuloplasty generated distinct morphologies with lower stresses. In the dilation anatomy, TEER alone left residual regurgitation, and annuloplasty improved the leaflet closure. Quantitatively, the model found that combined TEER + band annuloplasty yielded the smallest ROA (0.06 ), the largest CA (2.57 ), and reduced stresses relative to TEER alone. This study establishes a reproducible, open-source FEM framework for simulating transcatheter TEER and annuloplasty repairs. The framework enables quantitative evaluation of the mechanical impact of different transcatheter valve repair strategies, offers a foundation for extending virtual repair analyses to additional valve geometries, and supports the broader goal of incorporating virtual repair into procedure planning.

Finite element modelling for elucidating surface topography influence on cell-substrate interaction on fatty acid-modified PCL substrate.

Occlusal splints are a mainstay in the management of temporomandibular disorders, but the mechanical influence of design and thickness variations on joint and dental structures remains unclear. This study compared the stress and strain distributions within the temporomandibular joint (TMJ) and adjacent tissues produced by Michigan (stabilization) and non-permissive splints of 3-mm and 5-mm thicknesses using finite element analysis. Three-dimensional models of the maxilla, mandible, teeth, periodontal ligament, and articular disc were reconstructed from the Visible Human Project dataset. Michigan and non-permissive splints were modeled with occlusal thicknesses of 3mm and 5mm. Functional muscle forces were applied to simulate mandibular movements, and linear static analyses were performed in OptiStruct under defined boundary conditions. The splint-free model showed the highest stress levels in all structures. Non-permissive splints significantly reduced mandibular stress (32.3MPa) but increased loading on the periodontal ligament. Michigan splints resulted in lower periodontal ligament stresses and a more even stress distribution within the articular disc. Increasing splint thickness improved stress reduction only in the non-permissive model. Occlusal splints lowered peak stresses in the TMJ and related structures. Non-permissive splints provided greater joint protection, while Michigan splints achieved a more balanced distribution of occlusal forces. Splint design and thickness affect how loads are transferred through the temporomandibular system. Non-permissive splints, particularly at 5 mm, reduced joint stress but increased periodontal ligament loading. Splint selection should consider the main treatment goal, with attention to using the minimal effective thickness.

This study evaluates the role of aoudad (Ammotragus lervia) as a maintenance host and reservoir for significant respiratory pathogens hindering bighorn sheep (Ovis canadensis) conservation; Mycoplasma ovipneumoniae and leukotoxigenic Pasteurellaceae. An experimental commingling trial and regional disease surveillance revealed significant interspecies transmission risks and epidemiological patterns. Experimentally, 80% of bighorn sheep exposed to aoudad inoculated with M. ovipneumoniae and leukotoxigenic Pasteurellaceae died of pneumonia under both indirect and direct contact conditions. Conversely, aoudad exhibited prolonged relatively asymptomatic shedding of M. ovipneumoniae without severe clinical outcomes. Surveillance of 351 free-ranging aoudad revealed 9.4% with M. ovipneumoniae DNA in nasal swabs and M. ovipneumoniae-specific antibodies in 55.8%. Aoudad diagnostic profiles were heterogeneous across populations, including variations in strain diversity and distribution. Shedding rates were higher among juveniles than adults. Aoudad can sustain and transmit M. ovipneumoniae under free-ranging and experimental conditions, presenting significant risks to bighorn sheep populations. Research on strategies to mitigate pathogen transmission, such as reducing shared water access and aoudad removal, is critical for predicting complex biological outcomes for multi-species management. This study emphasizes the importance of longitudinal herd-specific disease surveillance and fundamental pathobiology research for understanding M. ovipneumoniae dynamics in aoudad to inform bighorn sheep conservation efforts in Texas.

Terfezia claveryi is a hypogeous fungus that forms desert truffles through ectendomycorrhizal symbiosis with Cistaceae plants in arid and semiarid environments. The study presented herein elucidates the organization and structure of the mating type (MAT) locus in this species and the spatio-temporal dynamics of T. claveryi strains in Helianthemum almeriense mycorrhizal plants and soil from nursery to field. MAT genes are the master loci controlling sexual reproduction and development in fungi. Our findings demonstrate that T. claveryi is a haploid and heterothallic species as its strains harbor and express either TcMAT1-1-1 or TcMAT1-2-1 genes as revealed by genome sequencing and RNAseq analyses. DNA-binding motifs located in their respective promoter regions appear to play a major role in the regulation of reproductive processes. The α-box and HMG-box domains are highly conserved along the Pezizomycetes and their strong structural similarity despite its poor sequence similarity supports a common evolutionary origin. Moreover, we set out a PCR-based approach to monitor the dynamics of T. claveryi strains of opposite mating type on mycorrhizal plants and soil. T. claveryi mycorrhizal plants at the nursery stage presented strains of both mating types, whereas a notable dominance of strains with the TcMAT1-1-1 gene was observed in field stage. Altogether, this research provides insights about genetic regulation and evolution of the MAT locus within the Pezizomycetes, and the reproductive biology of this important desert truffle, along with reliable markers to track the spatio-temporal distribution of strains of opposite mating types.

Global trends in norovirus genotype distribution among medically attended children with acute gastroenteritis, 2020-2025.

Abstract Flexible pressure sensors are vital for wearable health monitoring, human–machine interfaces, and soft robotics. However, current studies mainly improve sensor performance through material composition and fabrication processes, while the role of internal three-dimensional structures remains insufficiently explored. Inspired by natural marine sponges, this work presents a flexible pressure sensor with a bio-inspired porous scaffold architecture. By systematically designing and simulating different lattice geometries, we demonstrate that internal spatial structure strongly affects strain distribution, electrical response, and mechanical reliability. Finite element analysis shows that, among P, G, D, and IWP triply periodic minimal surface structures, the D-type design achieves the highest sensitivity of 11.099%. Based on this result, the optimal scaffold was fabricated using a sacrificial molding approach: a water-soluble polyvinyl alcohol mold was 3D-printed, filled with conductive silicone elastomer, thermally cured, and then dissolved to obtain the standalone conductive scaffold. Experimental results confirm that lattice geometry significantly influences sensor sensitivity, with the D-type structure exhibiting the best performance and reaching 9.28% sensitivity, consistent with simulation predictions. Wearable device demonstrations further verify its practical potential for pressure sensing. This study highlights that internal structural design, alongside material selection and fabrication strategy, is a critical factor in determining flexible sensor performance, offering a promising route for advanced wearable and biomedical sensing applications.

Influence of anatomical geometry and fiber dispersion on Achilles tendon Mechanics: A finite element modelling approach.

Deformation mechanisms and prediction of laser butt-welded thin-walled laminated cooling plates with equivalent section-modulus modeling and experimental verification

This study aims tooptimize the structural design of porous titaniumalloy scaffolds for mandibular defect repair. It investigates theimpact of different scaffold structures on the biomechanical propertiesof both the scaffold and surrounding bone tissue. Finite element modelsof rabbit mandibular defects were first established. Custom poroustitanium alloy scaffold models were subsequently designed using diamond(DI), cubic (C), and truncated cubic (TC) unit cell structures. Additionally,the structural design of the scaffold can be adjusted based on themechanical properties of the cellular structure. A porous titaniumalloy scaffold featuring a composite unit cell structure was developed.Finite element analysis was then performed to obtain the biomechanicalresponse characteristics of both the scaffolds and the surroundingbone tissue at the defect sites. The unit cell structure significantlyinfluences the stress, strain, and spatial distribution in both thescaffold and the surrounding bone tissue. Comparative analysis demonstratesthat scaffolds with composite unit cell structures possess superioroverall mechanical properties and deliver optimal biomechanical stimulation,thereby promoting new bone regeneration. These findings provide atheoretical basis for optimizing the scaffold’s structuraldesign.