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Composite plates are susceptible to various damages in complex conditions and working environments, which may reduce the reliability of the structure and threaten equipment and personal safety. Thus, the implementation of a robust online Structural health monitoring (SHM) system for these composite structures becomes imperative. To enhance reliability and safety, we introduce a robust online SHM system anchored by our newly developed damage detection Bayesian neural network (DD-BNN). The main contribution of this study lies in the DD-BNN to perform precise and reliable damage detection and localization in composite plates using only one actuator-receiver pair without any signal/feature pre-processing and human intervention. The proposed DD-BNN model innovatively combines probabilistic modeling with deep learning to address uncertainty in Lamb wave-based damage detection and model performance for composite plates, featuring a specialized probabilistic layer trained through Bayesian inference to efficiently encapsulate and manage uncertainty in model weights and activation. Notably, our method significantly simplifies the SHM system design and manual operation requirements. In addition, this approach not only reduces overfitting but also enhances robustness to noise, as confirmed by experiments on perturbation analysis of Gaussian and Poisson noise. [ABSTRACT FROM AUTHOR]

Pa0665 in Pseudomonas aeruginosa shares homologous sequences with that of the essential A-type iron–sulfur (Fe-S) cluster insertion protein ErpA in Escherichia coli. However, its essentiality in P. aeruginosa and its complementation with E. coli erpA has not been experimentally examined. To fulfill this task, we constructed plasmid-based ts-mutant Δpa0665/pTS-pa0665 using a three-step protocol. The mutant displayed growth defects at 42 °C, which were complemented by expressing ec.erpA. Microscopic observations indicated a petite cell phenotype for Δpa0665/pTS-pa0665 at 42 °C, correlated with the downregulation of the oprG gene. RNA sequencing revealed significant transcriptional changes in genes associated with the oxidative phosphorylation (OXPHOS) system, aligning with reduced ATP levels in Δpa0665/pTS-pa0665 under 42 °C. Additionally, the ts-mutant showed heightened sensitivity to H2O2 at 42 °C. Overall, our study demonstrates the essential role of pa0665 for OXPHOS function and is complemented by ec.erpA. We propose that the plasmid-based ts-allele is useful for genetic analysis of essential genes of interest in P. aeruginosa. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are organic pollutants and manufactured substances conferring toxicity to human health. The present study investigated whether pyrene, a type of PAH, harms rats. Our research provides an effective feature selection strategy for the animal dataset from Wenzhou Medical University's Experimental Animal Center to thoroughly examine the impacts of PAH toxicity on rat features. Initially, we devised a high‐performance optimization method (SCBA) and added the Sobol sequence, vertical crossover and horizontal crossover mechanisms to the bat algorithm (BA). The SCBA‐KELM model, which combines SCBA with the kernel extreme learning machine model (KELM), has excellent accuracy and high stability for selecting features. Benchmark function tests are then used in this research to verify the overall optimization performance of SCBA. In this paper, the feature selection performance of SCBA‐KELM is verified using various comparative experiments. According to the results, the features of the genes PXR, CAR, CYP2B1/2 and CYP1A1/2 have the most impact on rats. The SCBA‐KELM model's classification performance for the gene dataset was 100%, and the model's precision value for the public dataset was around 96%, as determined by the classification index. In conclusion, the model utilized in this research is anticipated to be a reliable and valuable approach for toxicological classification and assessment. [ABSTRACT FROM AUTHOR]

Clothing can absorb fine particulate pollutants from the atmosphere outdoors and then release them after entering the room in a form similar to three-handed smoke. In this study, the experimental site in Zhengzhou, a typical city with heavy pollution in central China, was used to investigate the adsorption and diffusion patterns of three different fabrics of polyester, polyester-cotton, and cotton clothing for fine particle pollutants, to guide people's behavior patterns and indoor air distribution, and to reduce indoor pollution exposure. The results showed that when garments of three different fabrics were exposed to moderate and heavy PM2.5 pollution for 1 h, 2 h, and 3 h, respectively, and then transferred to the diffusion chamber, polyester always released the highest PM2.5 concentration to indoor air during the same release cycle, followed by cotton and polyester-cotton. In addition, the concentration of indoor air pollutants will be periodically affected by the diffusion of fine particulate adsorbed by clothing fabrics. With the increase in outdoor pollution and exposure duration, the indoor PM2.5 concentration takes longer to stabilize at certain levels after the clothing is transferred to the indoor side. Finally, the comparison of natural ventilation experiments proved that it is not feasible to rely solely on natural ventilation to improve the influence of clothing pollution sources on indoor air quality. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) are recognized as a promising passive energy retrofit technology for existing buildings, as they are applied to the internal and external surfaces of the building with less impact on the original structure. However, the effectiveness of PCMs varies from region to region. Taking the Central Plains of China as an example, this paper investigated the effect of phase change temperature and material thickness variation on the energy efficiency of PCM when it was arranged on 14 placements including furniture through EnergyPlus (E+). And further explored the applicability of coupling PCMs with natural ventilation (NV). The results showed that: for the Central Plains of China, PCMs arranged on the internal surface of building roofs were optimal, and the reduction rate of uncomfortable degree hours could reach 38%, 26%, 24% and 40% after integrating PCMs into the roof, floor, external wall and furniture. The uncomfortable degree hour reduction rate per unit mass of PCM was 0.052%/kg for the roof, and the value of furniture was very close to the external wall and floor, which achieved 0.033%/kg. In addition, the coupling of PCM with NV improved the energy efficiency of PCM by more than twice. [ABSTRACT FROM AUTHOR]

• Exploring cooling behaviors beyond air conditioning in residential demand response. • Testing the effect of cooling behaviors on thermal comfort during demand response. • Identifying inaccuracy of prevalent thermal comfort models for demand response. • Developing more precise thermal comfort models for residential demand response. During periods of electricity demand response (DR) in residential buildings, inhabitants frequently engage in supplementary cooling behaviors, extending beyond the utilization of air conditioning (AC). However, the prevalent thermal comfort models, namely the Predicted Mean Vote (PMV) and Temperature Range Method (TRM), which are typically employed during DR periods, are designed for stable environments and do not consider the impact of these additional cooling behaviors. This study aims to develop novel thermal comfort models that more accurately reflect these behaviors during residential DR periods. The initial stage of the study involved a questionnaire survey conducted among residents in Zhengzhou, China, to investigate the AC usage patterns and additional cooling behaviors. Subsequently, typical AC DR strategies, which include increasing indoor temperature set points and turning off AC, along with the three most comment additional cooling behaviors, namely utilizing an electric fan, reducing clothing and consuming cold beverages, were examined through multi-scenario experiments. The findings from these experiments facilitated the development of two novel models: the PMV-DR model, indicative of the thermal comfort level, and the TRM-DR model, representative of the thermal comfort acceptance rate (AR) during the DR period. When compared with the traditional PMV and TRM models, these newly proposed models demonstrated greater consistency with the experimental results. As a result, these models could serve as the basis for thermal comfort evaluations during residential DR periods in the Zhengzhou region. Furthermore, they could provide a methodological benchmark for other geographical locales. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Pt/Bi 2 O 3 interfaces undergo structural reconstruction during CV process and form highly dispersed Bi0 species on the surface of Pt aerogel. • Higher MOR activity in alkaline media was obtained for Bi0 decorated Pt aerogel. • The reaction kinetics is investigated by In-suit FTIR measurement and DFT calculations. Improving the activity and stability of electrocatalysts for methanol oxidation reaction (MOR) is key important for the large-scale application of direct methanol fuel cells (DMFCs). Herein, we provide a novel scheme to firstly build Bi-decorated Pt aerogel through the structural reconstruction of Pt/Bi 2 O 3 interface, which demonstrates an excellent mass activity of 7.99 A mg-1 Pt in MOR (8-fold higher than that of commercial Pt/C). Experimental results show that the synergistic effect between Bi0 species and Pt aerogel is the major cause of the improvement of the catalytic activity. In-suit Fourier transform infrared (FTIR) Spectroscopy results indicated that the generation and transformation of HCOO– intermediate are accelerated. Density functional theory (DFT) calculations indicate that the decorated Bi enhances the adsorption of OH species on the adjacent Pt site, which can facilitate the dehydrogenation of methanol and the removal of poisonous CO species. Thus, the electro-catalytic performance can be improved. This strategy can be extended to construct other types of interfaces, which may open new routes for the synthesis of highly efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are a group of persistent organic global environmental pollutants and cause harmful effects on human health. Here, we evaluated adverse effects of chrysene, which is a four-ring PAH and an important member of 16 priority PAHs, on the liver. Chrysene was detected in some common raw and cooked Chinese food samples. Hepatotoxicity including increased relative liver weight, hepatocyte swelling and degeneration, and elevated serum alanine aminotransferase (ALT) levels were observed in chrysene-exposed C57BL/6 mice. Glutamine treatment effectively ameliorated chrysene-induced mice liver injury by decreasing serum ALT levels. Chrysene induced mice hepatic glutathione depletion and oxidative DNA damage with increased 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels. Hepatic expression levels of the aryl hydrocarbon receptor (AhR), AhR-related target genes including CYP1A1, CYP1A2 and CYP1B1, and AhR nuclear translocator (ARNT) were significantly increased in chrysene-exposed C57BL/6 mice. Chrysene induced mice hepatic mRNA levels of the nuclear factor erythroid 2–related factor 2 (Nrf2) and Nrf2-mediated phase II detoxifying and antioxidant enzymes including NQO1, UGT1A1, UGT1A6, SULT1A1, GSTm1, GSTm3, Catalase (CAT), GPx1, and SOD2. We found that chrysene had toxic effects including increased relative liver weight and elevated serum ALT levels on AhR+/+ mice but not AhR−/- mice. Chrysene significantly induced hepatic mRNA levels of CYP1A1 and CYP1A2 in AhR+/+ mice but not AhR−/- mice. To our knowledge, this study is the first to demonstrate that hepatotoxicity causes by chrysene is dependent on AhR, and Nrf2 plays an important regulation role in protection against oxidative liver injury induced by chrysene. • Chrysene is detected in some common raw and cooked Chinese food samples. • Chrysene causes mouse hepatotoxicity is dependent on AhR. • Chrysene causes mouse oxidative damage and glutathione depletion. • Nrf2-mediated antioxidant defense system is activated after chrysene exposure. [ABSTRACT FROM AUTHOR]