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Abstracts: Airborne fine particulate matter (PM2.5) can cause pulmonary inflammation and even fibrosis, however, the underlying molecular mechanisms of the pathogenesis of PM2.5 exposure have not been fully appreciated. In the present study, we explored the dynamics of glycolysis and modification of histone lactylation in macrophages induced by PM2.5-exposure in both in vivo and in vitro models. Male C57BL/6 J mice were anesthetized and administrated with PM2.5 by intratracheal instillation once every other day for 4 weeks. Mouse RAW264.7 macrophages and alveolar epithelial MLE-12 cells were treated with PM2.5 for 24 h. We found that PM2.5 significantly increased lactate dehydrogenase (LDH) activities and lactate contents, and up-regulated the mRNA expression of key glycolytic enzymes in the lungs and bronchoalveolar lavage fluids of mice. Moreover, PM2.5 increased the levels of histone lactylation in both PM2.5-exposed lungs and RAW264.7 cells. The pro-fibrotic cytokines secreted from PM2.5-treated RAW264.7 cells triggered epithelial-mesenchymal transition (EMT) in MLE-12 cells through activating transforming growth factor-β (TGF-β)/Smad2/3 and VEGFA/ERK pathways. In contrast, LDHA inhibitor (GNE-140) pretreatment effectively alleviated PM2.5-induced pulmonary inflammation and fibrosis via inhibiting glycolysis and subsequent modification of histone lactylation in mice. Thus, our findings suggest that PM2.5-induced glycolysis and subsequent modification of histone lactylation play critical role in the PM2.5-associated pulmonary fibrosis.

A ring-shaped plasmonic nanostructure is established for realizing the plasmonic field enhancement and focusing through a radial vector beam incidence. The plasmonic light field of the proposed nanostructure is simulated by finite-difference time-domain (FDTD). The results show that the obvious plasmonic field enhancement and focusing spot can be observed when a ring-shaped Au nanostructure is placed on the gold layer. Especially, the maximum of intensity ratio for single ring-shaped nanostructure can reach up to 41, the minimum of the full width at half maximum (FWHM) of focusing spot closes to 60 nm, and spot size beyond the diffraction limit is as small as 0.19λ0. Moreover, the plasmonic field enhancement and focusing can not be realized in the cases of linear polarization, circular polarization, and angular vector polarization incidences. What’s more, the double ring-shaped nanostructure can further develop the intensity ratio to 109 caused by the interference enhancement of surface plasmons. These research results may pave the way for designing the ultra-strong plasmonic field and plasmonic focusing devices.

Background: Most prior studies adopted a static residence-based approach in the assessment of noise exposure, which may lead to biased exposure estimates and misleading findings in noise–health relationships. Relatively little is known about personal noise exposure based on individuals’ space-time behavior and its effect on mental health. Objectives: This study aims to analyze and geo-visualize personal exposure to noise in various microenvironments based on individuals’ space-time trajectories at a very fine resolution and to further investigate the relationships between mental health and personal noise exposure at both the activity/travel episode level and the entire day level. Methods: Individual-level real-time data were collected with portable noise sensors and GPS trackers from a sample of 117 residents aged 18–60 years old from December 2017 to February 2018 in Beijing, China. Descriptive statistics and geo-visualization methods were used to examine how personal noise exposure varied across different activity types, travel modes, and among residents living in the same residential neighborhood on workdays and weekends based on individuals’ space-time behaviors. Logistic regression models were applied to examine the relationships between personal noise exposure and self-reported mental health. Results: We observed substantial differences in personal noise exposure across different activity types. The equivalent sound levels (Leq, dB(A)) for sleeping were the lowest, while the average Leq for work-related activities was the highest in indoor environments. The noise exposure levels for activities in outdoor environments were higher than indoor noise levels but differed between workdays and weekends. Variations in noise exposure associated with different travel modes were also evident, with the average Leq for public transport being much higher than that of other travel modes. A-weighted equivalent sound pressure level measured over 24 h for each individual (Leq,24h, dB(A)) varied significantly for residents living in the same residential neighborhood, ranging from 36 to 97 dB(A), with the majority of respondents being exposed to noise levels above 55 dB(A) on both workdays and weekends. Regarding the noise–health relationships, the modeling results showed that individual-level objective noise exposure based on space-time behaviors measured over a 24-h period (Leq,24h) was strongly associated with residents’ self-reported mental health. Higher exposure to noise was significantly associated with worse mental health. However, personal noise exposure at the activity/travel episode level (Leq) was not significantly associated with mental health on weekdays, but this link turned out to be significant in the weekend model. Conclusions: There were large variations in personal noise exposure associated with different activity types and travel modes, and the individual-level noise exposure varied significantly across time of day and between residents living in the same residential neighborhood. Variations in personal exposure strongly depend on different space-time behaviors and individual-specific microenvironments experienced in daily life, and they were significantly correlated with mental health.

We study spectral responses in a bright-dark mode ellipse-shaped resonators coupled waveguide. The results show that the plasmon-induced transparency (PIT) can be observed in the ellipse-shaped resonators coupled waveguide, and the symmetric line shape at the PIT window can be tuned by the radii of the long axis in ellipse-shaped resonators, the coupling distance, and the symmetry broken degree. Interestingly, the radii of the long axis for the bright mode and dark mode have opposite effect on the spectra of PIT. Our research results may pave the way for the understanding and tuning of PIT.

We study dual-Fano resonances and its sensing properties in a crossed ring-shaped metasurface by use of the finite-different time-domain (FDTD) simulation. The results show that the dual-Fano resonances in the proposed crossed ring-shaped metasurface are caused by the interaction among three local surface plasmon resonances (LSPRs), and spectra of the dual-Fano resonances can be tuned by the radius of the circular ring (CR) nanostructure, the distance between the center of the two CRs in x direction, and the polarization of the incident light. Interestingly, single Fano resonance splits into dual-Fano resonances in the case of the asymmetric ring structure arrangement or the non-y-axis polarized incident or the distance d

This study assesses the impact of secondary orientations on the tensile deformation behavior of single-crystal superalloys at mid-temperature of 760 °C. Tensile tests and stress-strain analyses were performed on specimens with primary orientation [001] and secondary orientations [100], [410], and [110]. Stress distributions were modeled using Abaqus software, while fracture behavior, slip system activation, oxidation, lattice rotation, and micro-dislocation movements were investigated using optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM). Findings reveal that the [100] orientation, due to the activation of coplanar dual slip systems, underwent significant strain hardening, exhibiting the highest strength and lowest ductility due to restricted lattice rotation. In contrast, the [410] and [110] orientations, each with a single primary slip system, showed reduced strength. The [410] orientation demonstrated enhanced ductility due to extensive lattice rotation, whereas the [110] orientation displayed the lowest strength, primarily due to premature cracking aligned with slip lines on the surface oxide film. Dominant deformation microstructures involved isolated stacking faults (SFs) shearing into γ′ precipitates, with the formation of immobile dual Lomer-Cottrell (L-C) locks at intersecting slip planes significantly contributing to microstructural strengthening.

Estimates of seasonal variation in plant stoichiometry and water use efficiency (WUE) are critical for predicting the time courses of carbon and water fluxes. However, the relationship between seasonal stoichiometry and WUE, and their relationship with climatic factors remains unclear. The carbon isotope composition has been widely used to evaluate the WUE. We hypothesized that WUE is closely related to seasonal variation in plant stoichiometry, and then stable carbon isotope can be used to indicate the variation in future models. For this study, we investigated seasonal changes in WUE and 14 elements (C, N, P, S, K, Na, Ca, Mg, Al, Fe, Mn, Zn, Cu, and Ba) of Quercus variabilis in a warm temperate forest, Central China. The WUE gradually reduced from late spring until leaf senescence in fall. Leaf C and N initially increased and then decreased. Leaf P, S, and K generally decreased, whereas Ca, Ba, Al and Fe gradually accumulated throughout the growing season. Leaf C:N, C:P, and N:P were lowest in early season, and then typically increased. As expected, WUE was positively correlated with N, P, S, K, and Mg, while negatively with C, Ca, Al, and Fe as well as C:N, C:P, and N:P. WUE increased with higher temperatures but had no relationship with precipitation. Leaf N, P, S, and K increased, while C:N, C:P, and N:P decreased with higher temperatures. Our results suggested that seasonal stoichiometry and WUE was closely coupled with plant growth, and temperature may be the main dynamic driver of water and nutrients in forest ecosystems. As WUE was estimated by carbon isotope composition, our findings provide new insights toward integrating carbon isotope with Earth system models.