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Engineered wood or mass timber has gained increasing popularity in building construction, and layered engineered wood is a major category of mass timber design since it enables manufacturing structural members with a wide range of geometry. Thus, there is a potential rising demand for structural health monitoring on engineered wood-based structural members and buildings. This study investigates the feasibility of using an important and practical acoustic emission (AE) method for damage localization, specifically two-dimensional (2D) AE source localization, in a representative layered engineered wood sample, namely laminated veneer lumber (LVL) plate. While 2D AE source localization is generally straightforward in isotropic materials, the problem becomes challenging for anisotropic materials with angle-dependent wave velocities. It is even more complicated if heterogeneity involves, which turns out to be the case for layered engineered wood. In this study, we rely on the AE feature of difference in time of arrival (dTOA) and develop three methods to address the challenges of 2D AE source localization raised by anisotropy and heterogeneity in an LVL plate. The benchmark velocity profile method (VPM) is first implemented in an LVL plate. With knowledge of the angle-dependent velocity, the source location predictions by the VPM are generally erroneous even with predicted source location outside of the region of interest. Furthermore, the general regression neural network (GRNN) is developed using different combinations of dTOA components, resulting in improved prediction performance. Third, the Gaussian process regression (GPR) is developed by maximizing the marginal likelihood of the training dataset. Moreover, to lessen the computation burden, the lower bound of the logarithm likelihood of the whole models is derived and decomposed through Jensen's inequality and Bayes' theorem, providing the theoretical background for training models with different combinations of dTOAs individually. [ABSTRACT FROM AUTHOR]

The clinical application of photodynamic therapy (PDT) is hampered by the suboptimal tumor-targeting properties of photosensitizers (PSs) and the presence of abundant antioxidants in cancer cells. To overcome these limitations, in this study, we proposed a formulation of an Ir-(III) complex into a promising tumor-targeted coordination polymer (Ir-PB), which could self-assemble into nanoparticles (Ir-PB NPs) for bioimaging and tumor-targeted PDT. Ir-PB NPs were found to efficiently target A549 cells and specifically accumulate in the mitochondria. Under light irradiation (400 nm, 10 mW/cm2, 15 min), Ir-PB NPs could trigger cell death through a combination of apoptosis and ferroptosis pathways by the photoinduced depletion of nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione (GSH) and the photoinduced production of single oxygen (1O2). The mechanisms featured the attenuation of the antioxidant capacity of tumor cells, the reduction of mitochondrial membrane potential (MMP), decrease in ATP production, activation of Caspase-3 protein, accumulation of lipid peroxidation (LPO), shrinkage of mitochondria, and down-regulation of glutathione peroxidase 4 (GPX4). The effectiveness of Ir-PB NPs in inhibiting tumor growth upon light irradiation was confirmed using an A549 xenograft mouse model. This study presents a promising strategy for developing photodynamic drugs that have excellent tumor-targeting abilities and enhance the efficiency of PDT. [ABSTRACT FROM AUTHOR]

Aim: Diagnostic methods for HSV-1 need to be updated. Materials & methods: Serial dilutions of HSV-1 DNA and ocular pathogenic microorganisms were tested by loop-mediated isothermal amplification-lateral flow dipstick assay (LAMP-LFD assay). The reliability of the LAMP-LFD assay and quantitative real-time PCR (qPCR) for HSV-1 detection was also validated using 30 clinical swab samples. Results: The LAMP reaction is optimal at 65°C and 30 min. And the LAMP-LFD assay could detect HSV-1 up to 10 copies/μl and no cross-reactivity with other pathogens was observed. Moreover, LAMP-LFD had similar positive rates to qPCR in clinical samples, and sensitivity and specificity were highly consistent with those of qPCR. Conclusion: LAMP-LFD assay is a rapid technique for the diagnosis of HSV-1. [ABSTRACT FROM AUTHOR]

The perturbation method, the Edgeworth series, the reliability-based optimization, the reliability sensitivity technique, and the robust design are employed to present a practical and effective approach for the robust reliability design of the Banjo flange with arbitrary distribution parameters on the condition of known first four moments of original random variables. The theoretical formulas of robust reliability design for the Banjo flange with arbitrary distribution parameters are obtained. The respective program can be used to obtain the robust reliability design parameters of the Banjo flange with arbitrary distribution parameters accurately and quickly.