Effects of waste oyster shell replacing fine aggregate on the dynamic mechanical characteristics of concrete.

Waste oyster shells (WOS) have the potential to serve as a construction material, offering a sustainable alternative to traditional fine aggregates in the production of WOS concrete. This can play a critical role in reducing environmental issues resulting from the overexploitation of river sand and the haphazard disposal of WOS. Although existing research has predominantly focused on understanding the static mechanical characteristics of concrete when WOS is employed, the dynamic mechanical properties have still received less attention. To understand the impact of WOS as a substitute for fine aggregates on the dynamic mechanical properties of concrete, a series of tests employing Split Hopkinson Pressure Bar (SHPB) were carried out. The findings demonstrate that the peak stress and elastic modulus increase as the WOS substitution ratio (Sr) increases from 0 to 20% but exhibit an exponential decline as Sr increases from 20 to 100%. This response can be explained by the joint effects of the pore-filling effect caused by WOS sand and the increasing air content caused by WOS sand. As Sr increases from 0 to 20%, the pore-filling mechanism becomes predominant as the water absorption rate decreases slightly from 4.31 to 3.83%. However, for Sr increasing from 20 to 100%, the negative influence of the air content becomes the primary contributing factor, where the water absorption rate increases from 3.83 to 14.68%. Furthermore, under the same impact pressure, the concrete with Sr = 20% absorbed the most energy, providing the best dynamic mechanical performance. These findings highlight the potential use of WOS in concrete for improving its dynamic characteristics, promoting both sustainable construction and enhancing the material properties in impact-resistant structures.

Xiaoqinglong decoction suppresses childhood cough variant asthma and inhibited the body inflammatory response by regulating IL-6/STAT3 signalling pathway.

Xiaoqinglong decoction (XQLD) is widely used clinically in the treatment of childhood cough variant asthma (CVA). However, its potential mechanism is still unknown. In the present study, the authors investigate the biological network and signalling pathway of XQLD in treatment of childhood CVA using network pharmacology-based analysis and experimental validation. By using the Bioinformatics Analysis Tool Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM) database, the authors confirmed the correlation between XQLD and asthma, and the authors screened 1338 potential target genes of Mahuang and Guizhi, the most active herbs in XQLD. By overlapping "Childhood asthma-related genes" of DisGeNET database, the authors identified 58 intersecting genes of Childhood asthma and 1338 target genes of Mahuang and Guizhi. The intersecting genes were used to construct the protein-to-protein interaction and performed Gene Ontology (GO) functional and the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. Gene Ontology enrichment analysis demonstrated 359 Biological Process terms, 16 Cellular Component terms, and 26 Molecular Function terms. Meantime, 75 terms of Kyoto Encyclopedia of Genes and Genomes signalling pathway were involved in enrichment analysis. These candidates showed a significant correlation with inflammatory response and positive regulation of tyrosine phosphorylation of STAT protein. In addition, XQLD treatment significantly upregulated serum interferon-γ expression, and downregulated serum interlukin-6 expression of CVA mice. XQLD treatment significantly inhibited phosphorylation of STAT3 in bronchial-lung tissues. Our data suggest that XQLD effectively alleviated bronchial-lung tissue damage in CVA mice and inhibited the body inflammatory response by regulating interlukin-6/STAT3 signalling pathway.

Mechanisms of Er Chen Tang on Treating Asthma Explored by Network Pharmacology and Experimental Verification.

OBJECTIVE: The aim of this study is to explore the active ingredients of ECT and their targets for asthma and investigate the potential mechanism of ECT on asthma. METHODS: Firstly, the active ingredients and target of ECT were screened for BATMAN and TCMSP, and functional analysis was done via DAVID. Then, the animal model was induced by ovalbumin (OVA) and aluminum hydroxide. Eosinophil (EOS) counts, EOS active substance Eosinophilic cationic protein (ECP) and eotaxin levels were detected following the instruction. Pathological changes in lung tissue were examined by H&E staining and transmission electron microscopy. Interleukin (IL-4, IL-10, IL-13, TNF-α), TIgE and IgE levels in bronchoalveolar lavage fluid (BALF) were measured by ELISA. Finally, the protein expression of the TGF-ß / STAT3 pathway to lung tissue was detected by Western Blot. RESULTS: A total of 450 compounds and 526 target genes were retrieved in Er Chen Tang. Functional analysis indicated that its treatment of asthma was associated with inflammatory factors and fibrosis. In the animal experiment, the results showed that ECT significantly regulated inflammatory cytokine (IL-4, IL-10, IL-13, TNF-α) levels in (P<0.05, P<0.01, reduced EOS number (P<0.05) and also ECP and Eotaxin levels in the blood (P<0.05) in BALF and/or plasma. Bronchial tissue injury was obviously improved on ECT treatment. Associated proteins in TGF-ß / STAT3 pathway were significantly regulated by ECT (P<0.05). CONCLUSION: This study originally provided evidence that the Er Chen Tang was effective in the treatment of asthma symptoms, and its underlying mechanism might be the regulation of inflammatory factor secretion and the TGF-ß/STAT3 signaling pathway.

The Effect of Pore Structure on Impact Behavior of Concrete Hollow Brick, Autoclaved Aerated Concrete and Foamed Concrete.

Porous concrete is an energy absorption material, which has been widely used in civil engineering, traffic engineering and disaster reduction engineering. However, the effect of pore structure on the impact behavior of the porous concrete is lacked. In this study, a series of drop-weight impact tests were carried out on three typical types of porous concrete, i.e., concrete hollow brick (CHB), autoclaved aerated concrete (AAC) and foamed concrete (FC), to investigate the effect of pore structures on their impact behavior. For comparison, static load tests were also conducted as references. According to the damage to the samples, the developments of impact force, strain, contact stress-strain relationship and absorbed energy during drop-weight during the impact test were measured and analyzed. The results show that the ratio between the peak impact stress and compressive strength of CHB was 0.44, while that of AAC and FC increased to about 0.6, indicating that the small and uniform pore structure in AAC and FC had a higher resistance against impact load than the hollow cavity of CHB. In addition, the elastic recovery strain in AAC increased by about 0.2% and its strain at peak contact stress increased by about 160% for a comparison of CHB, implying that a small open pore structure could enhance ductility. Besides, the peak contact stress of FC was close to that of AAC during impact loading, while the strain at peak contact stress of FC increased by about 36% compared with AAC, revealing that the closed-pore structure could further enhance the deformation potential. Correspondingly, the energy absorption rates of CHB, AAC and FC were 85.9 kJ/s, 54.4 kJ/s and 49.7 kJ/s, respectively, where AAC decreased by about 58% compared with CHB, and FC decreased by about 10% compared with AAC.