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A hydroxy graphene oxide (HGO)@Ag–nanoparticles (Nps) coating was fabricated on Ti6Al4V alloy by nanosecond laser direct energy deposition (LDED). The physical and chemical characteristics of obtained coating were performed using a transmission electron microscope (TEM), X–ray photoelectron spectroscopy (XPS), Fourier transform infra–red (FTIR) spectrometer and Raman spectroscopy. The electrochemical performances of HRO@Ag–Nps coating in 0.9% NaCl and 10% bovine serum albumin (BSA) solutions were investigated using an electrochemical workstation, and the electrochemical mechanism was discussed by the density functional theory (DFT) calculation. The results show that the pore resistance of HGO@Ag–Nps coating in 10% BSA solution is larger than that in 0.9% NaCl solution, presenting the higher corrosion resistance. The combined nanostructure between the cysteine of HRO@Ag–Nps coating and the methylene of BSA solution is caught by TEM, and the composite model of DFT and electrochemical impedance spectroscopy (EIS) verify that the BSA nano–layer is formed on the coating surface with the covalent hydrogen bond. Moreover, the result of DFT calculation also demonstrates that the band gap of HGO@Ag–Nps coating in 10% BSA solution tends to 0 eV, which improves its electrochemical performance in 10% BSA solution.

Heat treatment plays a positive role in alloy coatings during the corrosive‐wear and electrochemical process, in which the heating temperature is a key factor in the improvement of microstructure. In this work, the laser‐cladded NiCoCrAlY coating is processed by heat treatment, and the effects of heating temperature on the microstructure, corrosive‐wear, and electrochemical properties of obtained coatings are investigated. The results show that the average coefficients of friction and wear rates of NiCoCrAlY coatings are decreased with the increase of heating temperature, and the wear mechanism is mainly abrasive wear, adhesive wear, and pitting corrosion. Moreover, the corrosion resistance of NiCoCrAlY coatings is decreased with the increase of heating temperature, which is attributed to the precipitation of phases along the grain boundaries at high temperatures. [ABSTRACT FROM AUTHOR]

Background: Phasianidae mitogenomes exhibit significant structural variations critical for understanding evolution and subspecies divergence. However, annotations of these features in some pheasant species remain limited. This study aimed to enhance understanding of Phasianidae mitogenomes and their evolutionary patterns. Methods: A comparative analysis of complete mitogenomes from Phasianus colchicus, Phasianus versicolor, and 22 other accipitrids was conducted, examining codon usage, rRNA structures, selective pressures, phylogenetics, and structural variations. Results: The mitogenome of P. colchicus is 16,696 bp, comprising 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region, with a base composition of A: 30.61%, T: 25.26%, C: 30.85%, and G: 13.28%. Phylogenetic analysis revealed P. colchicus and P. versicolor are closely related, with the following relationship: ((Phasianus + Chrysolophus) + (Crossoptilon + Lophura)). Divergence timing aligns with the Tibetan Plateau uplift during the Tertiary Pliocene. Ka/Ks analysis suggests the CO I, CO II, CO III, ND1, ND4L, and ND6 genes in Phasianus underwent strong selective pressure for plateau adaptation. Conclusions: The study confirms Phasianus monophyly and its close relationship with Chrysolophus. Adaptation-related selective pressures on the CO I, CO II, CO III, ND1, ND4L, and ND6 genes highlight its role in plateau environments, offering valuable insights into pheasant phylogeny. [ABSTRACT FROM AUTHOR]

Key Points: Question: Is balloon angioplasty plus aggressive medical management superior to aggressive medical management alone for the treatment of severe symptomatic intracranial atherosclerotic stenosis (sICAS)? Finding: In this randomized clinical trial that included 501 patients, the composite outcome of any stroke or death within 30 days or an ischemic stroke or revascularization of the qualifying artery after 30 days through 12 months occurred in 4.4% of patients in the balloon angioplasty group and 13.5% of patients in the aggressive medical management group, a statistically significant difference. Meaning: The findings suggest that balloon angioplasty plus aggressive medical management may be an effective treatment for sICAS, although the risk of stroke or death within 30 days of balloon angioplasty should be considered in clinical practice. Importance: Previous randomized clinical trials did not demonstrate the superiority of endovascular stenting over aggressive medical management for patients with symptomatic intracranial atherosclerotic stenosis (sICAS). However, balloon angioplasty has not been investigated in a randomized clinical trial. Objective: To determine whether balloon angioplasty plus aggressive medical management is superior to aggressive medical management alone for patients with sICAS. Design, Setting, and Participants: A randomized, open-label, blinded end point clinical trial at 31 centers across China. Eligible patients aged 35 to 80 years with sICAS defined as recent transient ischemic attack (<90 days) or ischemic stroke (14-90 days) before enrollment attributed to a 70% to 99% atherosclerotic stenosis of a major intracranial artery receiving treatment with at least 1 antithrombotic drug and/or standard risk factor management were recruited between November 8, 2018, and April 2, 2022 (final follow-up: April 3, 2023). Interventions: Submaximal balloon angioplasty plus aggressive medical management (n = 249) or aggressive medical management alone (n = 252). Aggressive medical management included dual antiplatelet therapy for the first 90 days and risk factor control. Main Outcomes and Measures: The primary outcome was a composite of any stroke or death within 30 days after enrollment or after balloon angioplasty of the qualifying lesion or any ischemic stroke in the qualifying artery territory or revascularization of the qualifying artery after 30 days through 12 months after enrollment. Results: Among 512 randomized patients, 501 were confirmed eligible (mean age, 58.0 years; 158 [31.5%] women) and completed the trial. The incidence of the primary outcome was lower in the balloon angioplasty group than the medical management group (4.4% vs 13.5%; hazard ratio, 0.32 [95% CI, 0.16-0.63]; P <.001). The respective rates of any stroke or all-cause death within 30 days were 3.2% and 1.6%. Beyond 30 days through 1 year after enrollment, the rates of any ischemic stroke in the qualifying artery territory were 0.4% and 7.5%, respectively, and revascularization of the qualifying artery occurred in 1.2% and 8.3%, respectively. The rate of symptomatic intracranial hemorrhage in the balloon angioplasty and medical management groups was 1.2% and 0.4%, respectively. In the balloon angioplasty group, procedural complications occurred in 17.4% of patients and arterial dissection occurred in 14.5% of patients. Conclusions and Relevance: In patients with sICAS, balloon angioplasty plus aggressive medical management, compared with aggressive medical management alone, statistically significantly lowered the risk of a composite outcome of any stroke or death within 30 days or an ischemic stroke or revascularization of the qualifying artery after 30 days through 12 months. The findings suggest that balloon angioplasty plus aggressive medical management may be an effective treatment for sICAS, although the risk of stroke or death within 30 days of balloon angioplasty should be considered in clinical practice. Trial Registration: ClinicalTrials.gov Identifier: NCT03703635 This randomized clinical trial investigates the efficacy of balloon angioplasty plus aggressive medical management vs medical management alone in the treatment of patients with symptomatic intracranial atherosclerotic stenosis. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel approach to coordinate-based acoustic emission (AE) source localization to address the challenges of limited and imbalanced datasets from fiber-optic AE sensors used for structural health monitoring (SHM). We have developed a hybrid deep learning model combining four generative adversarial network (GAN) variants for data augmentation with an adapted inception neural network for regression-based prediction. The experimental setup features a single fiber-optic AE sensor based on a tightly coiled fiber-optic Fabry-Perot interferometer formed by two identical fiber Bragg gratings. AE signals were generated using the Hsu-Nielsen pencil lead break test on a grid-marked thin aluminum plate with 35 distinct locations, simulating real-world structural monitoring conditions in bounded isotropic plate-like structures. It is demonstrated that the single-sensor configuration can achieve precise localization, avoiding the need for a multiple sensor array. The GAN-based signal augmentation expanded the dataset from 900 to 4500 samples, with the Wasserstein distance between the original and synthetic datasets decreasing by 83% after 2000 training epochs, demonstrating the high fidelity of the synthetic data. Among the GAN variants, the standard GAN architecture proved the most effective, outperforming other variants in this specific application. The hybrid model exhibits superior performance compared to non-augmented deep learning approaches, with the median error distribution comparisons revealing a significant 50% reduction in prediction errors, accompanied by substantially improved consistency across various AE source locations. Overall, this developed hybrid approach offers a promising solution for enhancing AE-based SHM in complex infrastructures, improving damage detection accuracy and reliability for more efficient predictive maintenance strategies. [ABSTRACT FROM AUTHOR]

Composite materials/structures are rapidly advancing, offering improved product efficiency, cost-effectiveness, and superior specific properties. These materials find increasing applications in corrosion resistance and load-carrying structures across industries such as aerospace, wind turbines, transportation, and medical equipment. Therefore, ensuring reliable non-destructive evaluation of composites is crucial to address safety concerns and minimise maintenance expenses. The microwave non-destructive evaluation (NDE) method is particularly well-suited for characterising the material properties of composites. In our study, we utilise a large flange open-ended rectangular waveguide (OERW) probe, measuring 152 mm x 152 mm, to assess the complex reflection coefficient of dielectric materials. This measurement enables the extraction of essential material parameters using a forward electromagnetic model combined with an optimised method. To enhance accuracy, we introduce an iterative conjugate gradient descent (CGD) optimiser with adaptive segmentation. This approach effectively avoids local minima and reduces disparities in integrand values, resulting in precise measurements of material properties. Our proposed method provides estimations of the dielectric constant within a range of 1 to 10 and accurately determines sample thickness with a controlled limit of 3% error across all samples. Furthermore, we observe that as the loss-factor value decreases, the error in calculating the loss-factor of samples increases, which is supported by numerical analysis. [ABSTRACT FROM AUTHOR]

Structured light sensing systems, as one of the most common optical-based nondestructive evaluation techniques, have been widely applied for inline pipeline inspection. The sensor can be inserted inside the pipe to generate 3D visualisation and evaluate the cracks in the materials. The precise calibration of the camera-projector measurement system is of great significance to ensure the measurement accuracy of the 3D sensing system. Conventional calibration methods for structured light sensors involve complicated and time-consuming procedures and are easily affected by ambient light. The paper presents a novel algorithm to automatically calibrate the projection module and estimate the stereo parameters between the camera and the projector. The calibration algorithm exploits the cylindrical nature of the inspected pipe to create a set of geometric constraints and automatically calibrate the sensor without the need for reference calibration points. Experimental and simulation results showed that the algorithm could successfully estimate the projector's intrinsic and extrinsic parameters by simply acquiring the data inside a cylindrical pipe with a known diameter. The proposed algorithm highly reduces the data collection time for the calibration (only 53 s), improves the accuracy, and simplifies the calibration process. [ABSTRACT FROM AUTHOR]