Search Results (582)

Static pulling tests are essential for evaluating tree mechanical stability, hence the ability to sustain wind loading. In the tests, the trees are usually pulled in one direction, which can raise concerns about the bias of the estimates due to thigmomorphogenetic adaptations to wind, hence the effect of pulling direction. In this study, the effect of pulling direction on tree mechanical stability estimates (basal bending moment at primary and secondary failures) was assessed based on data collected from trees growing in stands regenerated naturally and by mounding. Scots pine (Pinus sylvestris L.) stands in three sites with slightly differing wind climates in hemiboreal forests in Latvia were studied. Pulling direction (difference between wind and pulling direction) had a significant effect on basal bending moment at fatal failure, indicating pulling direction-related bias that was not affected by stand regeneration. Stand regeneration had a significant effect on susceptibility to primary failure, which is intrinsic permanent wood damage, implying altered strength of storm legacy effects. Primary failure, however, was not affected by pulling direction. Full article

Facial biometric templates are permanent identifiers: once exposed, the underlying identity cannot be reissued, so single-copy storage is a critical single point of failure. This study protects facial templates by combining a non-invertible BioHashing transform and authenticated encryption with a threshold secret-sharing layer that distributes the protected record across independent storage nodes and reconstructs it only when a quorum of shares is collected. Two threshold schemes, previously proposed by our group for fingerprint and for general confidential data, are, for the first time, applied to facial templates and compared on a common platform as a resource-aware architecture: a non-positional polynomial notation scheme with the Chinese remainder theorem, and a verifiable multivariable-function scheme. Both reconstruct the template exactly and, across 2000 trials per attack, resist or detect every attack in our evaluation (for example, malicious-share tampering is detected in 100% of 2000 trials and stolen-token recovery succeeds in 0 of 2000), whereas a single read breach of one-copy storage discloses the template in full. Below the threshold they differ: the polynomial scheme is a compact, deterministic ramp scheme for edge and Internet-of-Things nodes that discloses only ciphertext bytes and, under separate key and token storage, neither the biometric nor the key; the multivariable scheme adds native share verification and, in its randomized single-secret mode, provides information-theoretic perfect secrecy for a single high-value secret, while for the packed record it is a verified ramp. Rather than ranking the schemes, we quantify this trade-off. Because the protection layer is lossless, recognition accuracy is inherited unchanged from the face encoder; on the LFW verification protocol, the complete pipeline attains an equal error rate of 2.12% ± 0.57% (95% CI [1.77%, 2.47%]) against a per-fold raw-embedding cosine baseline of 1.37% ± 0.62%. Full article

Carbon-fiber-reinforced polymer (CFRP) reinforcement is a potential alternative to steel in corrosive environments. However, CFRP is elastic without ductility, and the seismic performance of CFRP-reinforced concrete (RC) columns is inadequately understood. This study characterizes the intrinsic seismic response of concrete columns reinforced with CFRP cable-type bars and spirals under recorded near-fault ground motions. Three reference steel-RC columns are designed as seismic-resistant, non-seismic-resistant, and with post-cracking stiffness equivalent to the CFRP-RC column. The CFRP-RC and seismic-resistant steel-RC columns were tested under cyclic loading, and the results validated finite element (FE) models. Validated models simulated four columns under cyclic loading, and under 11 near-fault records matched to a capacity-derived elastic target spectrum. The results, bounded by selected ground motions and material constitutive models, show that: (1) The tested CFRP-RC column dissipated about 50% less energy than the steel-RC reference; (2) No material-level failure criterion was met under the suite, although peak base shears exceeded the nominal quasi-static capacities; (3) The CFRP-RC column developed the largest transient drift but minimal residual drift, whereas the steel-RC columns limited transient amplitude via hysteretic dissipation yet accumulated permanent offsets; (4) Response of the CFRP-RC column depends on ground motion energy delivery characteristics: concentration, symmetry, and duration. Full article

Three-dimensional (3D) printing technology has become more and more popular in restorative dentistry; however, information regarding the mechanical properties of 3D-printed restorative materials remains limited. The aim of this study was to evaluate the behavior under compressive loading until fracture of occlusal veneers fabricated from two types of 3D-printed resin composites, Saremco Print Crowntec A2 and Voco V-Print C&B Temp A2, intended for permanent and temporary clinical restorations, respectively. The study design involved scanning a first upper premolar typodont tooth, previously prepared to receive an occlusal veneer restoration, followed by the computer-aided design of the occlusal veneers and resin dies and 3D printing, resulting in 20 samples. The cemented restorations were subjected to mechanical testing using a fracture-resistance test at a speed of 5 mm/min, applied until failure. The recorded failure forces ranged between 571 and 970 Newton (N), values that are comparable to physiological masticatory forces. The absorbed energy was calculated as the area under the force–displacement curve using the trapezoidal integration method. The mean energy at failure was 0.301 Joule (J) (Voco) and 0.244 Joule (J) (Saremco), with Voco demonstrating greater toughness. In terms of fracture pattern classification, the 3D-printed resin with a lower filler content presented a more catastrophic failure mode compared with the material with a higher filler content. Fractographic analysis revealed characteristic fracture patterns and failure-specific features. Higher predictability and greater fracture strength were observed for the low-filled material, as indicated by the Weibull analysis. Full article

Uhthoff’s phenomenon (UP) is a transient, fully reversible exacerbation of pre-existing neurological deficits in multiple sclerosis (MS) patients, triggered by minor elevations in core body temperature. In clinical practice, UP is a frequent source of distress, often misidentified as an acute inflammatory disease relapse. This narrative review provides a critical analysis of UP, addressing methodological heterogeneity in its epidemiological estimates, its clinical presentation, and its differential diagnosis from true relapses. Mechanistically, we synthesize traditional concepts of temperature-dependent conduction block with modern insights into neuroenergetic failure, mitochondrial dysfunction, inflammatory mediators, and autonomic dysregulation. Furthermore, this work delineates current management strategies, establishing a clear distinction between robust evidence-based interventions and expert-informed practical guidance for patient education, physical rehabilitation planning, targeted active/passive cooling, and pharmacological approaches. Characterized as a pseudo-relapse, UP occurs independently of novel focal neuroinflammation. In conclusion, an isolated episode of Uhthoff’s phenomenon (UP) represents a transient, functional conduction block and does not inflict acute, permanent structural damage to the axon. However, emerging frameworks suggest that frequent, repeated episodes subject the already demyelinated axon to recurrent metabolic strain. Over time, these successive neuroenergetic crises do not directly destroy the fiber, but they may gradually exhaust the cell’s metabolic reserve. This cumulative stress potentially increases long-term secondary axonal vulnerability, making the axon more susceptible to the progressive neurodegenerative processes inherent to multiple sclerosis. Full article

Composite overwrapped pressure vessels are increasingly used for hydrogen storage because of their lightweight construction. Ensuring their structural integrity therefore becomes an important requirement for safe operation. Ultrasonic guided waves are well suited for this task because they are highly sensitive to structural changes in thin-walled pressure vessels. In this work, we developed a machine learning framework based on interpretable Best Daubechies Wavelet features and k-Nearest Neighbors novelty detection. The framework identifies a persistent transition in the UGW response during overpressurization that is indicative of a permanent structural change and occurs prior to burst failure. It was validated using measurements acquired from a real-world pressure vessel. For the a priori selected sensor pair 11–12, located in the highly stressed cylindrical section, the method achieved a balanced accuracy of 98.28% and a true negative rate of 100%. In addition, the proposed methodology identified the pressure level at which the persistent structural transition first became detectable and showed that this transition remained detectable after the vessel had returned to its normal operating pressure. Full article

On 22 August 2025, a partially erected section of the Jianzha Yellow River Super Bridge collapsed during cable-tensioning operations, causing 13 fatalities and leaving 3 persons missing. The bridge was being designed as a 366 m main-span continuous steel truss arch, which was erected via cantilever construction supported by a temporary cable-supported fastening system. This document-based forensic engineering synthesis uses the published official investigation report and independently accessed design and technical literature. No independent site inspection, component examination, raw data review, original video review, or validated nonlinear collapse reconstruction was undertaken; the exact instant and progressive development of splice failure are not visible in the report-reproduced chronology and remain unresolved. The official investigation identified bolt-group shear failure and separation at a tower-top distribution beam splice as the initiating physical event following second-stage tensioning of the No. 4 tie cable. These accident-specific findings are not redetermined in the present study; its original contribution is the evidence-status separation and engineering synthesis of the reported evidence through construction-stage load-path reconstruction, connection mechanics assessment, quantitative consistency checks, robustness interpretation, and safety barrier analysis. The reported bolt deficiencies are examined through a limited author-derived normalization combining the material-strength and threaded shear-plane effects at the individual-fastener level; this indicator is used only as a consistency check and is not interpreted as bolt-group or complete splice capacity. Enlarged and irregular holes, missing fasteners, and unauthorized field modifications are interpreted as further impairing bolt-group load sharing. The evidence-constrained load-path assessment indicates that the officially identified splice separation would have interrupted a primary temporary support path while the permanent arch action had not yet developed. Visible cantilever descent was followed by cable rupture, arch-rib fracture, and extensive collapse within approximately 10 s. A qualitative fault-tree and bow-tie analysis organizes the reported procurement, fabrication, design, installation, inspection, monitoring, and governance deficiencies and identifies high-leverage preventive, verification, and consequence-limiting barrier pathways. The findings support consequence-based classification, independent verification, formal hold points, robustness assessment, and personnel exclusion for safety-critical temporary works. Full article

Background and Objectives: Antibody–drug conjugates (ADCs) have become a major therapeutic platform in breast cancer and other solid tumors. Trastuzumab deruxtecan (T-DXd), trastuzumab emtansine (T-DM1), and sacituzumab govitecan (SG) differ substantially in antibody target, linker, payload, drug-to-antibody ratio, and bystander effect, resulting in heterogeneous pulmonary and cardiac toxicity profiles. This narrative review critically compares interstitial lung disease (ILD)/pneumonitis and cardiotoxicity associated with these three agents, aiming to prevent inappropriate extrapolation of toxicity algorithms and to provide a practical, agent-specific framework for multidisciplinary care. Materials and Methods: A targeted narrative search of PubMed/MEDLINE, Google Scholar, ClinicalTrials.gov, regulatory product information, and oncology/cardio-oncology guidance was performed and updated on 24 August 2026. Priority was given to regulatory documents, pivotal trials, pooled safety analyses, real-world cohorts, systematic reviews, and multidisciplinary recommendations. Pharmacovigilance data and case reports were included only to characterize rare events. Results: T-DXd is associated with a clinically important ILD/pneumonitis risk (approximately 12–15% in pooled analyses), predominantly grade 1–2 but occasionally fatal, requiring proactive surveillance, immediate interruption for suspected disease, and grade-directed corticosteroid therapy. T-DM1 shows a low but established pneumonitis incidence of approximately 1%, with permanent discontinuation recommended upon diagnosis. SG-related pneumonitis is rare and incompletely defined, without a T-DXd-like surveillance mandate. Both T-DM1 and T-DXd retain trastuzumab-derived cardiac monitoring requirements; symptomatic heart failure remains uncommon, although protocol-defined LVEF declines appear more frequent with T-DXd. SG lacks an established cardiomyopathy signal. Conclusions: Cardiopulmonary toxicity of ADCs is agent-specific rather than a class effect. Monitoring intensity, diagnostic thresholds, and management pathways must be tailored to the individual drug, regimen, indication, dose, patient comorbidity, and prior therapy. Close collaboration among oncology, radiology, pulmonology, and cardio-oncology is essential to preserve both treatment efficacy and patient safety. Full article

In this paper, we introduce and systematically investigate several classes of localized Baer-type rings associated with a fixed idempotent element e, namely e-Baer, e-quasi-Baer, e-p.q.-Baer, e-PP, and e-APP rings. We develop a unified structural framework relating these localized annihilator classes to weak localized zero-product conditions, including weak e-symmetric, weak e-reversible, weak e-reflexive, and weak e-semicommutative properties. We establish the principal implication relations among these classes and, under suitable hypotheses, obtain equivalence results connecting several localized and global conditions. Examples and counterexamples are provided to distinguish the classes and to demonstrate the failure of converse implications in general. We further study the behavior of localized annihilator conditions under various algebraic constructions and infinite operations. In particular, we establish permanence and transfer results for left e-APP rings under matrix, polynomial, Laurent polynomial, monoid, skew monoid, and skew polynomial extensions, as well as under Morita equivalence. For formal power series extensions, where the left APP property is not preserved in general, we obtain two sufficient conditions on the corner ring eRe that ensure preservation of the left e-APP property. We also establish structural equivalences between left e-APP and left e-p.q.-Baer rings under suitable finiteness assumptions. These results provide a systematic connection between classical annihilator theory and its localized counterpart and extend the study of localized regularity and Baer-type properties in ring theory. Full article

Cement-stabilized crushed stone is widely used in semi-rigid pavement bases, but fatigue cracking can reduce pavement durability. Supersulfated cement-stabilized crushed stone is a promising low-carbon alternative, yet its fatigue behavior under the micro-expansion induced by ettringite (AFt)-seeded hydration has rarely been clarified. This study investigated the fatigue performance of AFt-seeded SSC-stabilized crushed stone with explicit consideration of the resulting self-stress, through paste expansion tests, splitting fatigue experiments, and a coupled finite element–discrete element analysis. The seeded paste developed a stable free expansion of approximately 400 με, which was converted to an equivalent expansion of 18.5 με and an estimated compressive self-stress of 0.283 MPa at the crushed-stone scale. The material reached a 90-day indirect tensile strength of 1.45 MPa, approximately 57.6% higher than that of the OPC-stabilized reference. Under comparable normalized stress levels of 0.45 and 0.49, the SSC-stabilized crushed stone achieved 17,441 fatigue cycles, exceeding the reference by 28%, with slower stiffness degradation and lower permanent deformation accumulation. Numerical simulation further showed that the self-stress delayed bond breakage and crack penetration, with simulated base fatigue failure at approximately 5.3 × 10⁵ cycles. These findings clarify the role of micro-expansion-induced self-stress in fatigue resistance. They also indicate its potential for durable, low-carbon pavement bases. Full article

Fast-switching transients and high dv/dt associated with PWM inverters exacerbate the reflected-wave effects in the motor feeder cable. This leads to higher motor-side overvoltages, which increase the stress on the motor winding insulation, potentially accelerating insulation degradation and increasing the risk of partial discharge within the motor windings. Moreover, the common-mode voltages at the motor terminals propagate through parasitic capacitive paths within the motor, inducing shaft voltages that lead to electric discharge machining (EDM) currents and premature bearing failure. This paper experimentally investigates the influence of motor feeder cable length and type (shielded and unshielded) on motor terminal overvoltage, shaft voltage, and bearing current behavior in an inverter-fed 11 kW permanent magnet synchronous motor drive system. Three cable lengths (1 m, 3 m, and 16 m) with shielded and unshielded configurations are evaluated under identical operating conditions. Measurements of line-to-line voltage, line-to-ground voltage, shaft voltage, bearing current, and EDM discharge currents are recorded and statistically analyzed to assess the influence of cable configuration. The study also examines the influence of the motor grounding configuration on common-mode current and bearing current behavior. Overall, the findings provide comprehensive insights into the influence of motor feeder cable on overvoltage, shaft voltage, and bearing discharge behavior, supporting informed cable selection for WBG inverter-fed electric drives. Full article

Akerlof’s classical theory of the “Market for Lemons,” which conceptualizes adverse selection driven by information asymmetry, established the foundation of information economics. While the traditional model assumes static equilibria among a limited number of agents, analyzing its behavioral dynamics within large-scale, complex network environments remains a highly relevant task in computational social science. This study extends the classical lemon market model into a nonlinear dynamical system on adaptive networks. We mathematically elucidate macro-level social phase transitions—specifically structural exclusion such as scapegoating and collective ostracism—induced by computational cognitive limits, and evaluate optimal intervention strategies to mitigate these systemic failures. Multi-agent simulations utilizing large-scale tensor operations demonstrate that autonomous edge rewiring under incomplete information does not merely result in the uniform displacement of high-quality goods as predicted by static theory. Instead, the network self-organizes into an irreversible structural division: a core group of influential agents monopolizes high-quality information, while marginalized agents are isolated into a peripheral “lemon echo chamber” where only low-quality information circulates. To address this structural pathology under a resource constraint limiting intervention to 10% of the total agents, we evaluated two distinct approaches. The results indicate that providing informational support to influential hubs functions as a trap that exacerbates systemic inequality, superficially elevating the overall market evaluation but permanently fixing the exclusion gap. Conversely, the forced maintenance and protection of “weak ties” bridging disconnected clusters constitutes the mathematically optimal solution to dissolve fragmentation, effectively eliminating the price gap and facilitating social inclusion. Furthermore, this study demonstrates that the mechanism of social exclusion exhibits strong hysteresis effects. A distinct tipping point governs the progression toward a fragmented lemon echo chamber. Interventions implemented after crossing this critical threshold fail to restore the system to its baseline state despite identical resource expenditure, confirming the presence of an irreversible phase transition. These findings establish that the collapse dynamics outlined in the classical lemon market serve as a generalized model for explaining contemporary collective ostracism driven by information cascades. Consequently, the analysis highlights the necessity of early intervention prior to critical thresholds and the systemic preservation of structural bypasses rather than post-hoc remediation. Full article

Background and Objectives: Stenting isolated Medina 0,0,1 ostial side-branch lesions can result in geographic miss or protrusion into the main vessel. Drug-coated balloon (DCB) angioplasty avoids a permanent implant, but lesion-specific outcome data remain limited. We assessed procedural performance, bailout stenting, and 6- and 12-month outcomes after an intended DCB-only strategy. Materials and Methods: In this retrospective, single-center observational cohort study, we screened 170 patients who underwent coronary DCB treatment at a single center between 1 January 2023 and 31 July 2025. Thirty-one patients with de novo isolated Medina 0,0,1 lesions were included. The primary endpoint was 12-month target lesion failure (TLF), defined as cardiovascular death, target-vessel myocardial infarction, or clinically driven target lesion revascularization (TLR). Results: DCB-only strategy success was achieved in 29/31 patients (93.5%), post-DCB angiographic success in 29/31 (93.5%), and study-defined overall procedural success in 31/31 (100%). Final TIMI grade 3 flow after DCB was present in 30/31 patients; no flow-limiting dissection occurred. Two patients required bailout stenting, one because of deterioration to TIMI grade 2 flow and one because of residual stenosis >30% with recoil. Thirty patients were alive with documented follow-up at 12 months; one patient died from a non-cardiovascular cause at month 1. No TLF was recorded within 12 months. One clinically driven TLR for target-lesion restenosis occurred at month 20, outside the prespecified window. Conclusions: In this selected cohort, an intended DCB-only strategy avoided stent implantation in most patients and had a low bailout rate. The findings support procedural feasibility but do not establish comparative efficacy. Larger prospective studies are required. Full article

The aim of this study was to investigate the effects of surface treatments and thermocycling on the shear bond strength of a 3D-printed permanent crown resin. A total of 120 disc-shaped specimens (10 × 3 mm) were fabricated using a 3D printer and randomly assigned to four groups according to surface repair protocols: airborne-particle abrasion with Al₂O₃, bur roughening, 37% orthophosphoric acid etching, and a control group with no surface treatment. All specimens received a silane coupling agent followed by an adhesive resin application, and repair was performed using a highly filled flowable composite. Each group was divided into three subgroups and subjected to 1000, 5000, or 15,000 thermal cycles. Shear bond strength was measured, failure modes were analyzed, and data were evaluated using two-way ANOVA and Tukey’s post hoc test (p < 0.05). The sandblasting group exhibited the highest bond strength (18.7 ± 5.0 MPa), which was significantly higher than the control (12.6 ± 3.7 MPa) and acid-etching (14.2 ± 3.8 MPa) groups (p < 0.05). Aging periods had no significant effect on bond strength (p > 0.05). Additionally, the interaction between surface treatment and thermocycling had no significant effect (p = 0.823). Under the tested conditions, airborne-particle abrasion resulted in the highest shear bond strength of 3D-printed permanent crown resin. Full article

High-speed permanent magnet motors, due to their high speed, compact size, and light weight, are increasingly widely used in renewable energy systems, electric pump drives, fuel cell air compressors, and other fields. As a core component of high-speed permanent magnet motors, the reasonable design of the rotor system structure directly affects motor stability. To ensure the safe and reliable operation of high-speed permanent magnet motors, this paper designs the structure of a certain type of high-speed electric pump rotor. First, the actual interference amount between the rotor permanent magnet and the high-temperature alloy sleeve under high-speed and high-temperature conditions is considered, and radial and tangential stress analyses are performed on both the rotor and high-temperature alloy sleeve to determine the optimal interference amount. Second, based on rotor dynamics and fluid–structure coupling theory, the natural frequency and critical speed of rotors under wet and dry modals are studied; on this basis, harmonic response analysis and fatigue assessment were conducted; furthermore, an elastoplastic mechanical model of the rotor sleeve is introduced to analyze the effects of interference amount and rotational speed on the sleeve’s yield failure; finally, the dynamic safety of the high-speed rotor structure is verified through modal tests and overspeed operation tests. The results show that the optimal interference amount for the rotor is 0.02 mm; the first-order critical speeds in both dry and wet modals are well above the rated speed of 40,000 rpm, with no risk of resonance; the minimum cycle for fatigue life is 6.9 × 10⁵, meeting usage requirements; the equivalent force on the rotor sleeve increases with speed and interference amount; when the speed exceeds 44,000 rpm, the sleeve undergoes plastic deformation and failure; modal test error is less than 5%. This paper provides theoretical basis and experimental support for the rotor structure design and strength evaluation of high-speed permanent magnet motor drive equipment. Full article