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Atmospheric elements can cause harmful effects on air quality and human health. Despite extensive research on PM2.5, there remains a limited understanding of the seasonal variations, origins, and associated health risks of specific elements in urban areas of the North China Plain. PM2.5 samples across four seasons were collected to investigate the seasonal variations, provenance, and health risks of 18 elements in urban Liaocheng. The concentrations of PM2.5 and total detected elements (TDEs) exhibited distinct seasonal patterns, with the biggest values occurring in winter, followed by spring, autumn, and summer. Fe, Ca, Al, and K were the most plentiful elements throughout the campaign, contributing 72.2% of TDEs. The enhanced concentrations of crustal elements were due to frequent dust storms in spring. Results from positive matrix factorization suggested that the dust source was only identified in spring, accounting for the largest percentage (37.0%), while secondary oxidation made the most significant contribution (34.6%) in summer, facilitated by higher temperatures and stronger sunshine. The relative abundance (41.6%) of biomass burning was highest in autumn, ascribed to intensified agricultural waste burning during the autumn harvest, especially in October. The contribution of coal combustion in cold seasons was substantially greater than in warm seasons, highlighting the role of increased coal burning for house heating in deteriorating air quality. Potential source function analysis showed that elements in Liaocheng originated from local and neighboring regions. The carcinogenic risk from the selected elements was notably stronger for adult males than for adult females and children, while the non-carcinogenic risk was stronger for children than for adults. Overall, these findings provide ponderable insights into the contamination characteristics and sources of elements, which are useful to inform effective measures for improving air quality and aerosol modeling. [ABSTRACT FROM AUTHOR]

Background: Milk allergy commonly occurs in children, mainly caused by bovine-derived casein (CAS) protein. Neutrophil-activating protein (NAP) of Helicobacter pylori plays an immunomodulatory role with potential to suppress Th2-type immune responses. Bacillus subtilis (B. subtilis) spores are commonly used as oral vectors for drug delivery. Objective: To investigate whether recombinantly expressed NAP on B. subtilis spores could be an effective treatment for CAS allergy in mouse. Methods: After CAS sensitization, mice were orally administered B. subtilis spores expressing recombinant NAP for 6 weeks. Allergic symptoms and parameters were evaluated after CAS challenge oral gavage, including allergic inflammation, splenic cytokines, and serum-specific antibodies. Protein levels of Toll-like receptor 2 (TLR2) and c-JUN in the jejunum tissue were measured by western blot. Bone marrow-derived macrophages (BMDMs) were stimulated with inactivated NAP spores to measure the influence on cytokine profiles in vitro. Results: NAP recombinant spore treatment significantly reduced allergic symptoms and intestinal inflammation. Interleukin-12 and interferon-gamma levels increased, whereas serum CAS-specific IgG1 and IgE levels decreased. TLR2 and c-JUN expression levels were elevated in the jejunal tissue. Inactivated NAP spores polarized BMDMs to the M1 phenotype and enhanced cytokine expression, which were inhibited by a TLR2 neutralizing antibody. Conclusion: NAP offers a new strategy in the treatment of CAS allergy by inhibiting the Th2 response, while eliciting macrophages to promote Th1 immune responses. Oral treatment of recombinant Bacillus subtilis spore was found effective against casein allergy, which delivered neutrophil-activating protein (NAP) of Helicobacter pylori. We explored that recombinant CotC-NAP spores could elicit macrophages M1 polarization through TLR2-dependent signaling pathway, which activate phosphorylation of NF-κB and c-JUN, further release cytokines like interleukin-12 and interferon-gamma to rectify the balance of Th1/Th2 and regulate the level of Tregs. [ABSTRACT FROM AUTHOR]

The imaging quality of ultrasonic phased array technology significantly affects the quantification of small defects inside metals. Moreover, traditional manual evaluation methods require a substantial amount of manpower and time, and they are easily influenced by subjective factors. To mitigate the impact of imaging quality on the automated quantification of defects, this study proposes an improved gcForest algorithm (AWGA-gcForest, Adaptive window genetic algorithm- gcForest). Firstly, the acquired ultrasonic full matrix data from the phased array is processed using full focusing A-scan technique. Additionally, a window averaging weighting method is introduced for ultrasound signal processing to eliminate the interference from incident waves and backwall echoes. Subsequently, a multi-scale adaptive sliding window adjustment strategy based on Mean Absolute Deviation (MAD) is employed to reduce the computational time complexity of the gcForest algorithm. Furthermore, a weighted approach optimised with a genetic algorithm is utilised in the cascade forest to improve the classification accuracy and generalisation capability. Experimental results demonstrate that the proposed method achieves an accuracy of 97.50%, precision of 97.26%, recall rate of 96.63%, and F1 score of 96.92, exhibiting higher detection accuracy compared to other models while also reducing time costs. [ABSTRACT FROM AUTHOR]

Treating 2‐acetyl‐1‐chloro‐1,2‐dihydro‐3H‐1λ3‐benzo[d][1,2]iodazol‐3‐one 1 f with sliver cyanate in dried chloroform was found to give hypervalent isocyanato‐iodine(III) reagent 5 in excellent yield, while the oxo‐bridged 1,1′‐oxybis(2‐acetyl‐1,2‐dihydro‐3H‐1λ3‐benzo[d][1,2]iodaz‐ol‐3‐one) 6 was obtained when a mixture of chloroform and water was used as solvent. Structure of these two hypervalent iodine reagents were established by X‐ray crystallography and their reaction with base, aniline, methanol and cyclic ether were investigated. A previously reported 1‐cyanato benziodoxole compound was revisited and its structure was revised. [ABSTRACT FROM AUTHOR]

Calendering is a crucial process in the manufacturing of lithium-ion battery electrodes. However, this process introduces several challenges to the current collector, including uneven stress distribution, stress concentration, and plastic pits, which ultimately impact electrode consistency and safety. It is important to note that the load exerted on the current collector during calendering cannot be determined solely through experimental means. Moreover, due to the extremely thin nature of the current collector, there is a size effect problem. To address these issues, this study establishes a lithium-ion battery cathode model based on real experimental data and conducts a numerical simulation of the calendering process. By obtaining the load applied to the current collector and incorporating it into the crystal plasticity model, we investigate the mechanical behavior of the current collector at the crystal level during calendering. The results demonstrate that the lithium battery cathode collectors undergo plastic deformation during calendering. Furthermore, current collectors with a smaller number of grains exhibit a more pronounced stress concentration zone, and their stress levels are highly sensitive to the crystal direction. The maximum stress fluctuation range can reach approximately 100 MPa. Conversely, current collectors with a greater number of grains exhibit a more uniform stress distribution during calendering and are less sensitive to the crystal orientation. Their stress levels remain stable within a smaller range, approximately 20 MPa. These findings justify and emphasize the importance of investigating the current collector at the microscopic level, thereby providing valuable research insights for the field of calendering. [ABSTRACT FROM AUTHOR]