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Corrosion of steel wires in cables is a frequent occurrence and is a major factor affecting the durability and safety of cables. Magnetostrictive guided waves have been employed to detect steel wire corrosion. However, due to the complexity of the geometry of the corrosion area, it is difficult to interpret the magnetostrictive guided wave testing signals. Hence, extracting features from testing signals to characterize the corrosion condition is a great challenge. This study proposes a topological feature for corrosion characterization of steel wire, which is extracted from the two-dimensional point cloud with optimal geometry structure of the testing signal based on persistent homology theory. Corrosion experiments were carried out on 30 galvanized steel wires. The experimental results indicate that the topological feature increases roughly linearly with the corrosion depth. Furthermore, compared to other features obtained from the time domain, frequency domain, and joint time–frequency domain, this topological feature can reflect the progression of corrosion more accurately. [ABSTRACT FROM AUTHOR]

Long span cable-stayed bridges face risks of fire and explosion accidents caused by vehicles transporting fuel or chemicals. Such accidents may lead to damage to the stay cables, which in turn reduces the load capability of the bridge. This report introduces a newly developed fire and blast protection system for the multi-strand stay cables of Rod El Farag Axis Bridge in Egypt. The protection system consists of a thermal insulation blanket wrapped on cables and a steel tube covered with an anti-blast layer. Fire and blast tests were carried out to verify the effectiveness of the developed protection system. [ABSTRACT FROM AUTHOR]

Estimation of heritability and genetic covariance is crucial for quantifying and understanding complex trait genetic architecture and is employed in almost all recent genome-wide association studies (GWAS). However, many existing approaches for heritability estimation and almost all methods for estimating genetic correlation ignore the presence of indirect genetic effects, i.e., genotype-phenotype associations confounded by the parental genome and family environment, and may thus lead to incorrect interpretation especially for human sociobehavioral phenotypes. In this work, we introduce a statistical framework to decompose heritability and genetic covariance into multiple components representing direct and indirect effect paths. Applied to five traits in UK Biobank, we found substantial involvement of indirect genetic components in shared genetic architecture across traits. These results demonstrate the effectiveness of our approach and highlight the importance of accounting for indirect effects in variance component analysis of complex traits. Author summary: Complex human traits are influenced by both genetic and environmental factors. Recent evidence suggests that genetic effects on human traits can sometimes be mediated by the environment. One example is that parental genomes could influence parental behavior and family environment, which, in turn, shape the phenotypes of their children. Since parent and offspring genotypes are correlated, these environmentally mediated effects will be captured by conventional genome-wide association studies and may potentially bias our interpretation of genotype-phenotype associations. In this work, we propose a principled statistical framework named PARSEC to partition the genetic components of single traits and the shared genetic components between traits into direct and indirect effect paths. It marks an important methodological innovation by resolving a limitation in almost all existing genetic correlation estimation approaches and may have broad and impactful applications in future GWAS analysis for complex traits that are affected by parental genetics and family environment. [ABSTRACT FROM AUTHOR]

Helicobacter pylori (H. pylori), creating a global infection rate over 50%, presents great challenges in clinical therapies due to its complex pathological microenvironment in vivo. To improve the eradication efficacy, herein we fabricated a pharmaceutical vesicle RHL/Cl-Ch-cal where cholesterol-PEG, calcitriol and first-line antibiotic clarithromycin were co-loaded in the rhamnolipid-composed outer lipid layer. RHL/Cl-Ch-cal could quickly penetrate through gastric mucus layer to reach H. pylori infection sites, and then effectively destroyed the architecture of H. pylori biofilms, killed dispersed H. pylori and inhibited the re-adhesion of residual bacteria (called biofilms eradication tetralogy). Moreover, RHL/Cl-Ch-cal activated the host immune response to H. pylori by replenishing cholesterol to repair lipid raft on the cell membrane of host epithelial cells. Finally, RHL/Cl-Ch-cal killed the intracellular H. pylori through recovering the lysosomal acidification and assisting degradation. In experiments, RHL/Cl-Ch-cal demonstrated prominent anti- H. pylori efficacy in the classical H. pylori -infected mice model. Therefore, the study provides a "comprehensive attack" strategy for anti- H. pylori therapies including biofilms eradication tetralogy, immune activation and intracellular bacteria killing. Multi-functional vesicles RHL/Cl-Ch-cal are composed of rhamnolipid, where clarithromycin, cholesterol-PEG and calcitriol are loaded in the hydrophobic region, which improve Helicobacter pylori eradication through biofilms eradication tetralogy, immune activation and intracellular bacteria killing. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper focus on parameter identification of the main cables of cable suspension structures. Based on the dynamic stiffness theory, an inverse analysis characteristic function (IAC function) for identifying the main cable parameters (such as cable tension, moment of inertia, cable length, and mass per unit length) is established. This function allows for the consideration of cable flexural rigidity, sag, inclination, and additional lumped masses sustained by the suspender. The effects of the cable tension and moment of inertia on the IAC function are investigated via a numerical method. On this basis, a method for identifying the two parameters based on the peak-ridges of the IAC function is proposed. The method comprehensively utilizes measured multimode frequencies. It is unnecessary to determine the fundamental frequency and frequency order. A 20-m real cable test with suspended lumped masses is conducted to verify the correctness of the proposed methods. With the increase in the weight of suspended lumped masses, the advantages of the proposed method are more obvious. For operational cable tension less than 50% of the cable breaking tension, the cable moment of inertia is less affected by suspended lumped masses. [ABSTRACT FROM AUTHOR]

The Stockbridge damper (SD) has been used for vibration mitigation of suspender cables subjected to vortex-induced and other types of resonant vibrations. This paper studies its effectiveness and robustness, as well as a simplified design method, by using full-scale suspender experiments. The experiments were conducted on a 36 m prototype suspender cable of a bottom-through arch bridge, and two SDs were designed to control, respectively, the first- and second-mode cable vibrations. The damping effects were tested by placing the damper at different locations, and the robustness of the damper was investigated by varying the cable tension force and hence the cable frequency, to produce deviations from the frequency tuning condition. Furthermore, combined effects of the two SDs were studied. The experimental results are discussed and compared with theoretical results based on complex modal analysis of a taut cable equipped with a linear tuned mass damper. The properties of the SD vibrating with small amplitude were used in the theoretical analysis. The experimental results show that the SD is effective and robust for suspender cable vibration control. The comparison indicates that the analytical analysis generally gives conservative predictions of the damping ratios as long as the damper is installed close to an antinode of the mode shape of the target mode. This suggests that the theoretical analysis can be used for practical design of SDs. [ABSTRACT FROM AUTHOR]

Renewable energy sources such as wind power and photovoltaics (PVs) have been increasingly integrated into the power system through power electronic converters in recent years. However, power electronic converter-driven stability has issues under specific circumstances, for instance, modal resonances might deteriorate the dynamic performance of the power systems or even threaten the overall stability. In this work, the integration impact of a hybrid renewable energy source (HRES) system on modal interaction and converter-driven stability was investigated in an IEEE 16-machine 68-bus power system. In this paper, firstly, an HRES system is introduced, which consists of full converter-based wind power generation (FCWG) and full converter-based photovoltaic generation (FCPV). The equivalent dynamic models of FCWG and FCPV are then established, followed by linearized state-space modeling. On this basis, converter-driven stability analysis was performed to reveal the modal resonance mechanisms between different renewable energy sources (RESs) and weak grids in the interconnected power systems and the multi-modal interaction phenomenon. Additionally, time-domain simulations were conducted to verify the effectiveness of dynamic models and support the converter-driven stability analysis results. To avoid detrimental modal resonances, a multi-modal and multi-parametric optimization strategy is further proposed by retuning the controller parameters of the multi-RESs in the HRES system. The overall results demonstrate the modal interaction effect between the external AC power system and the HRES system and its various impacts on converter-driven stability. [ABSTRACT FROM AUTHOR]

Bacteria in biofilms are more resistant to antibacterial agents than bacteria in planktonic form. Hence, antibacterial agents should be able to eradicate biofilms to ensure the best outcomes. Little is known about how well many antibacterial agents can disrupt biofilms. In this study, we compared sodium lauryl sulfate (SDS), rhamnolipids (RHL), and N-acetylcysteine (NAC) for their ability to eradicate mature biofilms and inhibit new biofilm formation against Helicobacter pylori, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus mutans. SDS and RHL effectively inhibited formation of five bacterial biofilms in a dose-dependent manner, even at concentrations below the minimal inhibitory concentrations (MICs), suggesting that their antibiofilm activities are unrelated to their antibacterial activities. In contrast, NAC at certain concentrations promoted biofilm formation by all bacteria except P. aeruginosa, whereas at supra-MIC concentrations, it inhibited biofilm formation against the four bacteria, suggesting that its antibiofilm activity depends on its antibacterial activity. NAC was ineffective at eradicating mature H. pylori biofilms, and it actually promoted their formation at concentrations >10 mg/mL. Our results suggest that RHL is superior at eradicating biofilms of H. pylori, E. coli, and S. mutans; SDS is more effective against S. aureus biofilms; and NAC is more effective against P. aeruginosa biofilms. Our results may help determine which antibiofilm agents are effective against certain bacterial strains and develop agents effective against specific bacterial threats. [ABSTRACT FROM AUTHOR]

Objectives: In this study, a stable bear bile-loaded pH sensitive in-situ eye drop gel was prepared for sustain delivery and enhanced therapeutic application., Materials and Methods: Bear bile-loaded in-situ ocular gels with different Carbopol/Hydroxypropyl methylcellulose (HPMC) ratios were prepared and their stability was tested in PBS at a series of pH at 40 ° C. The morphology was observed by SEM examination and rheology was observed by Rheometer equipped with a 60-mm cone-plate at apex angle of 1 ° . Gel erosion and release kinetics of Tauroursodeoxycholic acid (TUDCA) was determined by HPLC. While, the in vivo dwelling time was obtained after administering the fluorescent-loaded gel in ocular disease-free New Zealand rabbits. Finally, biocompatibility and toxicity was observed by irritation test and H&E staining of eye-ball tissues, respectively., Results: The bear bile-loaded in-situ ocular gel showed excellent stability at different pH (pH 5.0, 5.5, 6.0, 6.5, 7.0 and 8.0) up to 5 days, and bear bile extract significantly attenuated the gelling ability of the in-situ gel. The viscosity of in-situ gels formulation was decreased with increase in shear rate (0.01 to 100 s-1), and morphological examination of freeze-dried preparation showed three-dimensional reticular structure at physiological pH. The in-situ ocular gel exhibited promising sustained drug release up to 160 min in vitro , and showed prolonged retention time up to 3-folds in vivo . Finally, the biocompability data confirmed that the formulation did not induce any toxic effects and was completely compatible with eye tissues., Conclusion: pH sensitive in-situ ocular gel provides new research opportunities to efficiently treat eye diseases.