To reevaluate transpalatal arch (TPA) biomechanics for molar rotation by transitioning from the traditional linear beam model to a statically indeterminate elastic portal frame analysis. A mathematical model based on Castigliano's second theorem simulated the TPA as a curved portal frame. Different modes of rotational activation were applied to standard and omega-loop designs across variable palatal heights (10 mm to 18 mm) using stainless steel and beta-titanium, incorporating a 2° mechanical clearance to simulate clinical insertion conditions. Palatal height was the primary determinant of TPA stiffness, acting as a lever arm that converts sagittal forces into torsion. In unilateral activation, average to high palatal vaults (palatal height ≥ 14 mm) generated spontaneous neutrality through the interaction between structural compliance and mechanical clearance, where the moment on the nonactivated side dissipates entirely. Regarding stiffness, contrary to clinical assumptions, the omega loop provided modest additional flexibility (less than 5% for unilateral activation, up to 15% for symmetric activation). The TPA functions as a flexible elastic frame, not a rigid linear beam. Vertical legs significantly dampen the force system, rendering the omega loop mechanically redundant. Notably, compensatory bends, generally used for unilateral rotation activation, are often biomechanically unnecessary in high-vaulted patients, as the system naturally reduces the contralateral moment to zero within the mechanical tolerance of the attachment.
In the SCR systems of heavy-duty diesel engines, urea deposits formed under real operating conditions differ significantly from laboratory-prepared samples in morphology, composition, and structure. Under real operating conditions, the urea solution undergoes multiple dynamic deposition cycles, forming dense and compositionally complex stubborn deposits. Conventional laboratory methodssuch as single evaporation or single-layer liquid film modelsfail to replicate this process. To address this limitation, this study proposes a multilayer liquid-film heating crystallization method. The method is used to investigate the fundamental differences between crystallization on pre-existing crystal layers and static single-layer crystallization. Crystals derived from single-layer and multilayer liquid films of equivalent total thickness were analyzed using thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The results indicate that (1) the first urea crystal layer in multilayer crystallization impedes heat transfer to the second liquid film, promoting the formation of lower-temperature crystal components; (2) multilayer urea crystals require higher temperatures for thermal decomposition compared to single-layer crystals; (3) when the temperature decreases (with the first layer's crystallization temperature being not lower than the heating temperature of the second layer), the crystal mass from multilayer crystallization exceeds that from single-layer crystallization of equivalent liquid film thickness; (4) multilayer crystallization, involving secondary deposition and a superimposed thermal history, facilitates the development of ordered columnar or layered microstructures with relatively clean surfaces.
Silica aerogels are attractive thermal insulators because of their ultralow thermal conductivity. Nonetheless, their practical deployment is often limited by intrinsic brittleness and poor mechanical robustness. A weavable glass-fiber-reinforced silica aerogel composite is demonstrated, fabricated via in situ sol-gel growth on chemically modified fibers. Unlike traditional impregnation methods, silica nucleates and forms directly on the surface of the modified fiber to form an integrated network of fibers and aerogels with continuous interfacial connectivity. The interface is primarily stabilized through covalent Si-O-Si linkages between the silica network and the surface-functionalized fibers, whereas hydrogen bonding serves as a secondary interaction that further enhances interfacial stability. The resulting composite exhibits an ultralow thermal conductivity of 0.0150 W m-1 K-1 together with a high tensile strength, while preserving the intrinsic flexibility and weavability of the fiber scaffold. The material remains stable under direct flame exposure up to ∼1000 °C, exhibiting only 1.3% mass loss after cycling tests. In addition, hydrophobic modification imparts long-term water repellency, yielding a static water contact angle of 150°. This study establishes an interfacial engineering strategy for stabilizing aerogels within flexible and mechanically robust composites, providing a viable pathway toward aerogel-based thermal insulation in demanding environments.
Irreparable posterosuperior rotator cuff tears remain challenging, particularly in young, active patients. Superior capsular reconstruction restores static stability but is limited by graft failure and reduced external rotation, especially with infraspinatus fatty infiltration. Lower trapezius transfer restores dynamic force coupling but lacks static support. This Technical Note describes an arthroscopic-assisted mini-open technique combining superior capsular reconstruction with lower trapezius transfer using dual Achilles allografts. The graft's thickness provides durable, superior coverage, whereas a mini-open anterior portal extension simplifies graft passage and suture management. This combined approach integrates static and dynamic stabilization to improve stability and range of motion and to reduce subacromial contact pressures in patients with irreparable posterosuperior rotator cuff tears.
This study aims to evaluate the biomechanical effects of proximal fibular osteotomy (PFO) on tibiofemoral and proximal tibiofibular load transfer under simulated neutral and varus alignment conditions using a lower-extremity finite element analysis (FEA) model. A patient-specific three-dimensional FEA model of the lower extremity was developed from computed tomography and magnetic resonance imaging data of a healthy volunteer. Neutral, 3° varus, and 5° varus alignments were simulated before and after PFO under a simplified physiological axial load of 900 N. Tibiofemoral compartment forces, proximal tibiofibular joint (PTFJ) force, distal tibiotalar reaction force, and peak von Mises stresses within the cartilage-meniscus complex were evaluated. Proximal fibular osteotomy markedly reduced PTFJ force across all alignment conditions. Under neutral alignment, PTFJ force decreased from 122.94 N to 21.84 N, while distal tibiotalar reaction force increased from 787.55 N to 897.89 N, indicating redistribution of load through distal pathways. Tibiofemoral compartment forces changed minimally. Under 5° varus alignment, medial tibiofemoral force decreased only from 608.45 N to 603.78 N following PFO. Peak medial meniscal and cartilage stresses increased with varus alignment and remained largely unchanged after osteotomy. In this single-subject static FEA model, PFO substantially reduced proximal tibiofibular loading, but produced only limited changes in tibiofemoral load distribution under simulated varus alignment. Within the present model, load redistribution occurred predominantly through distal load-transfer pathways rather than substantial unloading of the medial tibiofemoral compartment. These findings suggest that the biomechanical effect of PFO may primarily involve alteration of fibular load transmission rather than meaningful reduction of medial knee loading.
How can leaders guide diverse organizations to work together on society's biggest challenges when power is unevenly distributed? Cross-sector partnerships (CSPs) bring together companies, governments, and nongovernmental organizations (NGOs) to address complex problems, yet their success hinges on how leaders navigate competing interests and shifting power dynamics. This study examines a high-profile CSP involving a Fortune 500 company, two international development organizations, and an NGO. Drawing on Mary Parker Follett's ideas about "power-with" and "power-over," I show how NGO leaders combined collaborative and more coercive tactics to move the partnership forward. My analysis reveals that responsible leadership (RL) in CSPs is not a static trait or style but evolves through a dynamic choreography of power as challenges and priorities change. The findings offer practical lessons for leaders seeking to balance ethics, inclusion, and influence in multi-stakeholder collaborations, and they extend theory by reframing RL as a shifting, context-sensitive process rather than a fixed style.
In the era of immunotherapy, head and neck squamous cell carcinoma (HNSCC) has demonstrated clear benefits from immune-based treatments and is widely regarded as a tumor type with high immunotherapeutic potential. These tumors are characterized by robust and persistent inflammatory responses that actively drive tumor initiation and progression while concurrently shaping their sensitivity or resistance to therapy. Inflammation simultaneously creates therapeutic vulnerabilities and barriers by altering tumor behavior and reprogramming the immune microenvironment. This review examined HNSCC through a tripartite prism of inflammation, immunity, and tumor biology to demonstrate how chronic inflammatory cues rewire immune cells, reshape signaling circuits, and remodel tissue architecture, ultimately altering responses to immunotherapy. We first examined how immune cell reprogramming occurs under inflammatory pressure. Macrophages, regulatory T cells, exhausted CD8+ T cells, and specialized dendritic cell subsets can switch roles-from tumor-clearing sentinels to promoters of tumor growth, stemness, and invasion. This plasticity-sometimes transient, sometimes entrenched-determines whether the immune ecosystem favors elimination or tolerance, and consequently whether immune checkpoint blockade succeeds or fails. Next, we catalogued the inflammation-linked pathways and readouts that capture these state changes. Signaling hubs such as NF-κB/STAT3, IL-6/TNFα, TGF-β, HA-CD44, and PI3K-4EBP1-SOX2 orchestrate the trade-offs between proliferation and invasion and govern cancer stem cell dynamics. Corresponding biomarkers-PD-L1, CD163/CD68 ratios, LAMP3, ALDH/SOX2, Zeb1, Vimentin, and CD44 isoforms-become far more informative when resolved at single-cell and spatial scales, thereby enabling sharper patient stratification. We then mapped the pathological interplay among tumor, stromal, and immune compartments. Extracellular matrix reprogramming, CAF heterogeneity, and the spatial polarity of immune infiltrates generate discrete micro-niches with distinct functional consequences. Spatial profiling can convert static pathology into a dynamic atlas of therapeutic opportunities. Finally, we outlined translational directions. Targeting inflammation and the microenvironment-via TAM reprogramming, cytokine blockade, or STING/CD47 pathway modulation combined with immune checkpoint blockade (ICB)-offers a rational strategy to improve outcomes. Altogether, these strategies point toward an ecology-aware approach to precision immunotherapy for HNSCC-one that reads and reshapes the tumor's inflammatory language rather than ignoring it.
The advent of single-molecule nanopore sequencing established a powerful platform for modern genomics by using static biological pores to report the translocation of canonical nucleic acids, enabling rapid, accessible nucleic acid analysis. However, extending this strategy to single-molecule proteomics has stalled against a fundamental biophysical bottleneck. Current efforts in nanopore proteomics attempt to retrofit these static, spatial "caliper" biological nanopores (e.g., α-hemolysin, MspA, CsgG, aerolysin) for protein sequencing despite the immense steric, charge, and conformational heterogeneity of proteins. Unlike the chemically uniform, polyanionic phosphodiester backbone of DNA, the proteome contains isosteric and isobaric variants that confound purely volumetric measurements made by static pores. To address this bottleneck, we propose the application of dynamical translocases - naturally evolved, protein-handling nanomachines (e.g., the anthrax toxin protective antigen). Unlike static pores that rely on passive diffusion, dynamical translocases employ target-docking clamp architectures that achieve low nanomolar sensitivity. Active-site conformational dynamics generate high-dimensional kinetic fingerprints that enable molecular discrimination during translocation. By coupling dynamical translocases with Physics-Informed Machine Learning (PIML), we demonstrate that amino-acid side-chain-dependent thermodynamic friction can be mathematically decoded, enabling >90% accurate classification of chemically distinct amino acid classes and doing so label-free without the artificial DNA-handles required by legacy platforms.
Direct oral anticoagulants (DOACs) are susceptible to drug-drug interactions involving both transport and metabolism. The relative contribution of intestinal transporters in DOAC pharmacokinetics, however, is uncharacterized, hindering the prediction of their drug interactions. In this study, we examined potential interactions of select precipitants with apixaban, dabigatran, edoxaban, and rivaroxaban using a 3-step static mechanistic combinatorial modeling approach. In this approach, we (1) calculated apparent estimates of the fractions of efflux transport (fe) of the 4 DOACs by the intestinal breast cancer resistance protein and intestinal permeability glycoprotein (P-gp), (2) validated our estimates, and (3) used them to simulate unstudied drug interactions with the anticoagulants. We estimated P-gp and breast cancer resistance protein transport to play a similar role in the interactions of apixaban and rivaroxaban (fe_P-gp = 0.21, fe_breast cancer resistance protein = 0.13). Additionally, the role of P-gp was prominent in the interactions affecting dabigatran etexilate (fe_P-gp = 0.61) and less so in those affecting edoxaban (fe_P-gp = 0.38). Using our apparent estimates, we predicted 144 interaction signals of 47 drugs with the 4 anticoagulants. All signals showed potential change >25% in the area under the curve of DOACs, warranting further investigation. Using our combined model, we were able to uncover new drug interaction signals, including previously unrecognized signals by kinase inhibitors. SIGNIFICANCE STATEMENT: Multiple enzymes and transporters affect direct oral anticoagulant pharmacokinetics. Drugs interacting with the same proteins may increase the levels of direct oral anticoagulants, leading to bleeding complications. Current methods predicting such interactions focus only on individual enzymes or transporters, limiting the prediction of cases where both may be involved. In this study, we combined multiple models to capture the complexity of interactions affecting direct oral anticoagulants. Using our validated model, we predicted 144 drug-drug interaction signals with potential clinical significance.
Environmental pollution remains an urgent global challenge that threatens ecosystems and human health. Silicon carbide, with its exceptional chemical inertness, excellent thermal conductivity, and highly tunable electronic structure, has emerged as a powerful dual-phase platform for environmental remediation. This paper critically reviews how precise electronic structure engineering unlocks the catalytic potential of silicon carbide architectures across both aqueous and atmospheric environments. In wastewater treatment, strategies such as constructing heterojunctions and single-atom loading are highlighted for their ability to narrow bandgaps, strengthen internal electric fields, and induce hydrogen spillover effects. These modifications successfully overcome the high dissociation energy barriers of recalcitrant contaminants like per- and polyfluoroalkyl substances. In atmospheric remediation, silicon carbide inherently eliminates thermal runaway during volatile organic compound oxidation and strategically manages temperature-dependent synergistic mechanisms for treating multi-pollutant exhausts. This work meticulously evaluates how complex real-world variables, specifically dynamic pH fluctuations, competitive inorganic anions, and the dual role of moisture, dictate catalytic efficiencies alongside advanced microwave-assisted systems. Furthermore, Density Functional Theory (DFT) calculations are integrated to elucidate the atomic-level thermodynamic barriers and site-specific cleavage pathways driving these enhanced performances. Crucially, this review exposes significant gaps in current research, notably the over-reliance on idealized reaction conditions and static theoretical models without operando validation. By bridging these mechanistic insights with real-world complexities, this paper provides a systematic roadmap for transitioning silicon carbide-based catalysts from laboratory concepts to industrially viable environmental purification technologies.
Chimeric antigen receptor T-cell (CAR-T) therapy has achieved remarkable success in hematologic malignancies, yet demonstrates limited efficacy in solid tumors, including hepatic cancers. T-cell exhaustion and insufficient persistence represent major obstacles. We hypothesized that optimizing both manufacturing processes and CAR structural design could reduce exhaustion and enhance therapeutic outcomes in immunocompetent mouse models of primary and metastatic liver malignancies. We systematically compared antibody-based versus bead-based activation methods, evaluating their effects on T-cell exhaustion phenotypes. Retroviral vector (RVV) production was optimized for murine T-cell transduction, assessing vector stability and T-cell phenotypes. Different cytokine conditions were tested for their impact on T-cell expansion, memory phenotypes, and anti-tumor efficacy using GPC3-targeted CAR-T cells in hepatocellular carcinoma models. Through structural prediction and electrostatic field simulation, we identified that high positive charge patches (PCP) in the EpCAM-targeting G8.8 scFv caused CAR clustering and tonic signaling. We generated charge-optimized variants and evaluated their therapeutic efficacy in an immunocompetent colorectal cancer liver metastasis model. Antibody activation showed superior homogeneity and expansion despite initially higher exhaustion markers, which equilibrated by day 10 without affecting viability. RVV harvested at 72 hours post-transfection yielded optimal titers. RVV remained stable through freeze-thaw cycles. IL-7 supplementation to IL-2 significantly enhanced memory phenotypes, reduced exhaustion, and improved tumor control in GPC3-CAR-T therapy. Electrostatic optimization of G8.8 scFv substantially reduced tonic signaling, decreased T-cell exhaustion, and enhanced anti-tumor efficacy in the MC38-EpCAM model. Systematic optimization of manufacturing conditions and structure-based charge engineering of CAR constructs synergistically enhance therapeutic efficacy against liver malignancies, providing a translatable framework for improving solid tumor CAR-T therapy.
Adult spinal deformity (ASD) alters sagittal alignment and trunk centre of mass location, increasing spinal loading. Current clinical assessment of ASD primarily focuses on alignment parameters disregarding patient's body shape variability. This study aimed to evaluate the relative effects of spinal sagittal alignment and body mass distribution (i.e., body shape) on spinal loads and trunk centre of mass location in upright-posture and forward flexion. Sagittal alignments of 754 patients with ASD were obtained from clinical data. Trunk mass distributions were assessed in adult male volunteers (10 healthy weight, 9 obese). Using an established musculoskeletal model of the spine, inverse dynamics simulations were performed for each combination of sagittal alignment and trunk mass distribution profile. A factorial analysis using generalised linear models elucidated the relative effects of alignment vs. body shape. Sagittal alignment primarily determined the antero-posterior positioning of trunk centre of mass; body shape, its cranio-caudal location. In the healthy weight cohort, the relative effect of mass distribution on compressive loads was 14-98% in the thoracic and 42-57% in the lumbar region. In the cohort with obesity, it was 24-98% and 19-27%, for thoracic and lumbar regions, respectively. Body shape effects on shear forces were greater in dynamic forward flexion than in static upright-posture. The considerable impact of mass distribution on spinal loads suggests that patient body shape should be considered in ASD surgical planning to avoid segmental overloading. Future research should evaluate body shapes in patients with ASD, including females and elderly subjects.
A complex spatial light modulator (SLM) based on three-phase covalent macropixels (3PCMPs) enables the generation of three-dimensional computer-generated holograms with inherent suppression of DC and conjugate noise. However, the noise-suppressed complex-field synthesis remains confined to the central viewing zone (VZ), imposing a fundamental limitation on the effective eye-box. We present a design of zone-switching 3PCMP SLM architecture that relocates the domain of noise-suppressed complex-field synthesis across a 3 × 3 array of addressable VZs in a pupil-tracked manner. The proposed scheme integrates a static six-level phase plate with active binary sub-pixel modulation to steer the complex signal toward the selected VZ while preserving suppression of DC and conjugate terms. Wave-optics simulations confirm effective zone switching of the complex signal and show substantially improved holographic image quality across higher-order VZs, enabling a 3 × 3 extension of the effective viewing zone. These results support the feasibility of extending the effective eye-box in complex holographic displays.
Autism spectrum disorder (ASD) is characterized by persistent deficits in social communication and the presence of restricted and repetitive behaviors. While ASD has a neurodevelopmental origin, it remains a lifelong condition, yet little is known about how its behavioral and neural features evolve across adulthood. Here, we investigated behavioral, synaptic, and structural alterations across the transition from early to mature adulthood in Cntnap2 knockout mice, a widely used model of ASD. Using a longitudinal behavioral approach combined with electrophysiological recordings and morphological analysis, we show that KO mice exhibit increased stereotyped and repetitive behaviors and reduced exploratory activity at both ages. However, detailed analysis of behavioral patterns revealed age-dependent differences, with early adult KO mice displaying increased behavioral persistence that later evolved into distinct patterns of behavioral sequences. These behavioral changes were associated with alterations in inhibitory synaptic transmission in the dorsolateral striatum (DLS), including changes in spontaneous inhibitory postsynaptic current (sIPSC) frequency and temporal structure. In parallel, mature adult KO mice showed structural remodeling of spiny projection neurons, characterized by increased distal dendritic arborization and age-dependent organization of dendritic spines. Together, our findings demonstrate that ASD-related alterations are not static but evolve across adulthood, revealing a multi-level reorganization of behavioral, synaptic, and structural features. These results highlight the importance of considering adulthood stages in ASD and provide new insights into the dynamic nature of the condition.
The most important objects - from predators to projectiles - are often those that are moving. Accordingly, visual systems are specialized for object tracking, and many models of such processing involve continually re-identifying surface features across space and time (as you might follow a tiger by keeping track of its orange stripes). Here, in contrast, we show across four experiments - and in phenomenologically compelling demonstrations - that people also spontaneously perceive and track change-defined objects, with no enduring surface properties from moment to moment. Observers viewed regular grids filled with hundreds of small elements (e.g. randomly oriented crosses). Change-defined objects were implemented by having an element change (e.g., from one random orientation to another random orientation), with these changes propagating through space and time. Observers still detected the 'second-order' motion in such displays - despite the lack of persisting features, and without being able to identify the object in any static frame. And beyond motion detection, observers also spontaneously perceived and tracked persisting objects - and were even able to perform multiple-object tracking. We also generalized this phenomenon in several ways, showing that it occurs with other types of changes (e.g., to brightness or shape), and even when different types of changes are haphazardly interleaved (e.g. with a random orientation change to one element followed by a random brightness change to its neighbor, etc.). In essence, these stimuli show how observers can track a tiger that is always fully hidden while moving through tall grass, by tracking variable local changes to the grass itself.
Standing balance is maintained through the integration of signals from the proprioceptive, visual, and vestibular systems. Galvanic vestibular stimulation (GVS) delivered through head-worn electrodes is increasingly used in clinical vestibular rehabilitation and immersive entertainment interfaces, but it is known to impact on-feet postural stability. Prior studies assessing balance and postural effects have predominantly focused on bilateral mastoid-based uniaxial GVS paradigms. Limited research has characterized balance metrics under multiaxial GVS configurations using four-electrode montages generating multiple directional stimulation paradigms. Standing balance was assessed in healthy participants with eyes closed using a dual force-plate system to record center-of-pressure (COP) dynamics. Participants were exposed to six randomized GVS stimulation conditions across four electrodes placed on the left and right mastoids, center forehead, and nape of the neck, while static, dynamic sway, and velocity-based COP features were extracted to characterize postural responses. GVS significantly altered static, dynamic sway, and velocity-based balance measures compared with the Null condition across six stimulation paradigms. All GVS stimulations increased COP displacement, sway length, sway area, and peak velocities, while reducing sway density metrics across mediolateral (ML) and anteroposterior (AP) axes. These findings provide an early quantitative characterization of postural responses to an unconventional GVS montage and create a foundation for predicting body motion during multiaxial vestibular stimulations. Such insights are important for the safe application of GVS in standing and ambulatory contexts, including clinical vestibular rehabilitation and immersive simulation environments.
Stretching is a common practice among athletes in sports requiring high flexibility, but the optimal duration and type of stretching to enhance performance while minimizing potential drawbacks remains unclear. This systematic review aims to evaluate the acute effects of different stretching durations and techniques-specifically static, dynamic, and combined methods-on flexibility and performance in athletes engaged in flexibility-dependent sports. Following PRISMA guidelines, a systematic search of PubMed, Web of Science, and Scopus was conducted up to March 2026. Twenty-three studies met the inclusion criteria, encompassing 627 athletes from sports such as gymnastics, swimming, wrestling, dance, and track and field. Data were synthesized using thematic analysis and percentage-weighted mean changes with 95% confidence intervals, comparing pre- to post-intervention outcomes or intervention groups to controls (depending on study design). Moderating variables such as stretching type and duration were also considered. Static stretching produced moderate improvements in flexibility from pre- to post-intervention (2.97%) and a moderate improvement when compared to control (2.36%), but was associated with small negative performance effects pre to post (-0.88%) and trivial declines compared to control (-0.07%). Dynamic stretching showed small flexibility gains (0.77%) compared to control, and small improvements in performance (0.55%). Combined protocols resulted in small positive effects on both flexibility (1.65%) and performance (0.60%). PNF interventions produced a small positive effect on performance (1.04%) when compared to control conditions. Regarding duration, short-duration stretching (≤60 s) led to a small flexibility improvement compared to control (0.79%), with trivial performance gains pre to post (0.06%) and compared to control (0.48%). Long-duration stretching (>60 s) yielded large flexibility improvements pre to post (6.21%) and a small improvement compared to control (1.89%), but small performance declines pre to post (-1.80%) and trivial effects relative to control (-0.02%). However, the majority of included studies were rated as low quality (15/23), and findings should be interpreted with caution. Stretching duration affects flexibility and performance. Long static stretching boosts flexibility but slightly reduces performance, while dynamic stretching enhances readiness with minimal flexibility gains. Protocols should match sport-specific demands and session goals. https://www.crd.york.ac.uk/PROSPERO/view/, identfier CRD42025635493.
A clear 3D understanding of complex skull base structures, including the cavernous sinus (CS), is vital for the endoscopic endonasal approach. However, traditional learning (TL) methods using textbooks and static materials have limits in fostering spatial comprehension. This study developed an interactive virtual dissection (VD) environment based on a virtual endoscopic skull base anatomy 3D computer graphics (VESA-3DCG) model to enhance 3D understanding of the sellar and parasellar regions and evaluated its educational effectiveness against TL methods. The VESA-3DCG model was constructed by modifying previously developed high-fidelity 3DCG models, which were designed with reference to the authors' previous anatomical studies of the sellar and parasellar regions, and integrated into a VD environment. Twenty-eight Japanese neurosurgical residents (postgraduate years 3-7) were randomly assigned to the VD or TL group. Both learning sessions were conducted remotely via a screen-sharing platform, allowing participants to view and interact with the presented materials in real time. A knowledge test covering four domains-bony landmarks, CS anatomy, microvascular anatomy, and neural anatomy-was administered before and after learning. Gain scores, defined as pre- to posttest improvement, were calculated per domain and overall. Group comparisons were performed to assess learning outcomes, and satisfaction and confidence were rated on a 5-point Likert scale. The final model, consisting of 304 components and about 18.6 million polygons, accurately depicted the microanatomy of the sellar and parasellar regions. The VD environment supported interactive manipulation, including transparency and translucency control, rotation, zooming, virtual drilling, and retraction. Gain score analysis showed that the VD group achieved greater overall improvement in anatomical learning relative to the TL group (p = 0.036), with the most robust difference observed in the CS anatomy domain (p = 0.001). Within-group analysis in the VD group confirmed notable posttest gains in bony landmarks, CS anatomy, and neural anatomy. Participants reported high satisfaction and confidence with the VD environment. The VD environment based on the VESA-3DCG model offered an effective, interactive platform for anatomical learning. It demonstrated favorable educational effects, particularly for anatomically complex regions such as the CS, and showed feasibility as a complementary tool to TL, including in remote education settings.
This study aims to compare the biomechanical performance of three different surgical fixation techniques in the treatment of proximal humerus fractures with medial metaphyseal defects. A total of 24 synthetic humerus bone models were used and equally divided into three groups (n = 8 per group). A standardized unstable proximal humerus fracture model with a medial metaphyseal cortical defect extending to the surgical neck was created using a three-dimensional (3D)-printed osteotomy guide. Group 1 received fixation with a lateral anatomical locking plate. Group 2 was treated with a combination of a lateral anatomical plate and a medial buttress plate (dual plating). Group 3 underwent fixation with an intramedullary nail (IMN); in this group, four specimens had distal locking with an endopin (Group 3a), and the other four with static screws (Group 3b). All specimens were subjected to axial loading until failure. Forces at the onset of failure and complete failure were recorded, and fracture patterns were documented. In Groups 1 and 2, transverse fractures consistently occurred at the level of the most distal screw of the lateral plate. In Group 3, failure was observed either proximally or distally at the nail tip, including butterfly fragment formation and metaphyseal collapse. Group 2 exhibited the highest resistance to axial loading, followed by Group 1 and Group 3, with statistically significant differences between all groups (p = 0.043, p = 0.0003, p < 0.00001). No significant difference was found between subgroups 3a and 3b (p > 0.05). Our study results indicate that double plating provides the greatest axial stability in proximal humerus fractures with medial metaphyseal defects, supporting its use in fracture patterns with medial column deficiency. However, as fixation choice should be guided by patient-specific factors and surgical feasibility, these findings should be interpreted in the context of experimental conditions and loading limitations.
Hyperoxemia is common in acute brain injury, but its clinical significance is unclear. Most supporting evidence comes from retrospective studies that reduce oxygen exposure to static metrics - mean, peak, or time-above-threshold PaO2 - obscuring the fact that patients with identical averages can have very diff erent exposure patterns: stable versus oscillating between hyperoxemic peaks and normoxic troughs. These patterns may not be biologically equivalent. Intermittent hyperoxia may activate adaptive Nrf2 or HIF-1α pathways resembling ischemic preconditioning, while sustained hyperoxemia may overwhelm them. Consistent with this, protocolized intermittent hyperoxia (hyperbaric or time-limited normobaric) has improved outcomes in severe traumatic brain injury and intracerebral hemorrhage in randomized trials, whereas uncontrolled sustained hyperoxemia is linked to harm in observational cohorts - particularly in subarachnoid hemorrhage, ischemic stroke, and post-cardiac-arrest patients, with no consistent harm signal in traumatic brain injury. We argue that future trials should move beyond liberal-versus-conservative comparisons toward metrics capturing the rate, frequency, and duration of oxygen fluctuations. Until then, sustained extreme hyperoxemia (PaO2 300 mmHg) should be avoided, while protocolized, time-limited hyperoxic exposure merits further study in patients with metabolic distress.