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The conversion of methane into high-value-added liquid chemicals such as methanol is an ideal means of carbon resource storage and recycling. However, the intricate catalytic steps and the presence of diverse reactive oxygen species (•OH and •O2–, etc.) obscure the oxygen sources and reaction pathways of the product C1 oxygenates. In particular, the frequent coexistence of CH3OOH and CH3OH in liquid products further complicates the matter. In this study, two distinct types of Au/TiO2 nanoparticle catalysts, i.e., one with nonselective deposition and another with selective deposition, were synthesized via chemical reduction and photodeposition, respectively. On this basis, we systematically investigated their photocatalytic performances in methane oxidation and successfully established the structure–activity relationship between the crystal surface and product selectivity. Mechanistic studies revealed that the {001} and {101} facets of TiO2 nanocrystals played dominant roles in the generation of CH3OH and CH3OOH primary oxygenates, respectively, due to their varying abilities to further convert •O2–. In addition, Au, serving as an electron acceptor, facilitates the reduction of oxygen to form •O2– and promotes facet-related reactions. These findings offered a great perspective for the development of methane photooxidation to produce liquid oxygenates. [ABSTRACT FROM AUTHOR]

In the manufacturing industry, the design of machining processes plays a pivotal role in determining the quality, efficiency, and cost of product manufacturing. Machining process design is progressing towards intelligence to meet the high demands for efficiency and effectiveness in smart manufacturing. Building upon traditional computer-aided process planning, intelligent technologies, such as machine learning and knowledge graphs, have emerged as key drivers in advancing intelligent process design. To address knowledge accumulation, inflexible reuse, and fragmented reasoning in machining process design, this paper organically integrates the structured representation characteristics of the knowledge graph and the perceptual reasoning capabilities of deep reinforcement learning. It introduces an intelligent generation method for machining process design based on knowledge graph and deep reinforcement learning, aiming to achieve unified representation and reasoning reuse for historical process cases and general process rules. The effectiveness of the proposed method is validated through a case study involving the generation of machining process solutions for a specific model of diesel engine components. This research contributes valuable insights to overcoming the limitations of traditional methods and enhancing the efficiency of the machining process design. [ABSTRACT FROM AUTHOR]

Compared to normal traditional Chinese timber buildings, citygate buildings are relatively high, lightweight, and quite vulnerable to wind. The present work aims to carry out a wind-induced vibration study on a traditional Chinese citygate building, the Nanjing Drum Tower, with the method of computational fluid dynamics (CFD) simulation to determine the wind loads and finite element (FE) analysis to assess its structural response. The architectural and structural characteristics of traditional Chinese timber buildings in the Ming-Qing dynasties are analysed. The Nanjing Drum Tower has typical characteristics and is taken as the representative building in this study. The wind pressure coefficients of the drum tower are obtained by CFD simulation with the Reynolds-averaged Navier-Stokes (RANS) model. The structural response of the drum tower under wind loads is analysed based on FE analysis. The obtained results can provide a basis for assessing the wind-induced vibration of traditional Chinese citygate buildings. [ABSTRACT FROM AUTHOR]

Early Chinese traditional timber buildings preserved until now are mainly ancient buildings built in the time of the Song and Yuan dynasties (960–1368 AD). Dou-gongs of these ancient timber buildings are complex structures. Their complexities, however, are difficult to fully consider in large-scale structural analyses. Therefore, it is necessary to develop a reliable simplified modeling of Dou-gongs, which is applicable for large-scale analyses. In this study, the features of Dou-gongs of early Chinese traditional timber buildings were firstly reviewed, referring to the historical literature and on-site investigation. Then, the mechanical behavior of typical Dou-gongs exposed to vertical loads was examined through refined finite element analyses, where the solid elements were adopted and geometric characteristics were considered. According to the results of the load transferring path, a new beam-truss model representing a simplified Dou-gong was developed, and its accuracy was numerically verified. The results showed that the gravity load of the roof above the column is transferred down through the central axis; the weight of the overhang of the roof is transferred diagonally to the bottom of the Dou-gong, passing through the front of the cantilever components; in the collapse condition, the vertical load is transferred to the two sides through horizontal beams. Compared with the results of the refined model, the new beam-truss model proposed shows an acceptable computational accuracy concerning stress, deformation and stiffness, with 90–97% reduction in the calculation time consumption, which makes it suitable for large-scale structural analyses of early Chinese traditional timber buildings. [ABSTRACT FROM AUTHOR]

Ancient Chinese stone arch bridges are an important kind of architectural heritage in China, and they are often threatened by potential collapse problems. The stone arrangements of the arches in ancient Chinese stone arch bridges are quite different from those in Western countries, which may lead to different collapse modes. Thus, the collapse mechanisms of arches with typical "Chinese stone arrangements" urgently need to be studied. In this paper, the stone arrangements commonly used in ancient Chinese stone arch bridges were first investigated and summarized in detail. Then, finite element models of four typical arches with different stone arrangements were established to study their mortar failure processes, collapse modes, and bearing capacities. After that, the influence of the friction coefficients of the voussoirs on the collapse modes and the bearing capacities of these typical arches was analyzed. The results show that the stone arrangements used in ancient Chinese stone arch bridges can generally be divided into three groups according to their lateral linkages. The bearing capacities of the four typical arches are sorted as follows when the friction coefficient is 0.3: the FJBL method > the HLFJBL method > the HL method > the BL method. When the friction coefficient decreases from 0.3 to 0.1, the live-load bearing capacities of these arches decrease by 33%–55%. When the friction coefficient increases from 0.3 to ∞, the live-load bearing capacities of these arches increase by 3%–11%. The study results can provide a scientific basis for the conservation of ancient Chinese stone bridges. [ABSTRACT FROM AUTHOR]

In order to study structural properties of Dingtougong mortise-tenon joints of Chinese traditional hall-style timber buildings built in the Song and Yuan dynasties, and to provide theoretical basis for structural analysis and scientific conservation of this type of architectural heritages. First, the main structural characteristics of the Chinese hall-style timber buildings built in the Song and Yuan dynasties were sorted out, including the structural forms, structural dimensions, and configurations of mortise-tenon joints. Then, the low cyclic loading tests of the six reduced-scale mortise-tenon joints were carried out, including the five groups of Dingtougong mortise-tenon joints, and the one reference group of mortise-tenon joint without Dingtougong. The results show that all the five groups of Dingtougong mortise-tenon joints have better structural performance than the one reference group of mortise-tenon joint on the aspects of ultimate capacity and rotational rigidity. In the five groups of Dingtougong mortise-tenon joints, the structural performance of the Dingtougong mortise-tenon joint with Dingtougong of through mortise-tenon joint is obviously superior to that of the Dingtougong mortise-tenon joint with Dingtougong of half mortise-tenon joint. Besides, considering material nonlinearity and contact nonlinearity, the finite element models of the six groups of mortise-tenon joints were built up by ANSYS, and the structural properties of these mortise-tenon joints under in-plane vertical load, out-of-plane horizontal load and torque load were analyzed and compared with the experimental results. The theoretical results very coincide with the experimental results. Under in-plane vertical load, the Dingtougong obviously improves the mechanical performance of the mortise-tenon joint. In addition, the relationships among the initial elastic rotational rigidity KY under in-plane vertical load, the initial elastic rotational rigidity KX under out-of-plane horizontal load, and the initial elastic rotational rigidity KR under torque load of these six groups of mortise-tenon joints were obtained, the results of which can provide theoretical base for structural analysis and conservation design of Chinese traditional hall-style timber buildings. [ABSTRACT FROM AUTHOR]

In the fast-paced world of product design, businesses seek a competitive edge by swiftly addressing user requirements and developing precise solutions. Depending on diverse knowledge, conceptual design makes enterprises invest significantly in knowledge management. Following the philosophy of decision-based design, a knowledge graph-aided decision guidance method is proposed to streamline and enhance knowledge utilisation in product conceptual design. Firstly, the decision-making process in product conceptual design is modelled using the Concept-Decision-Knowledge (CDK) model, yielding the meta-model of CDK (mCDK). A data-augmented BERT-BiLSTM-CRF model is adopted to extract information from diverse data sources, forming a CDK knowledge graph (CDK-KG). A decision case for employing problem-solving knowledge configuration is generated to resolve specific design decision problems when new requirements arise. Validation of the method is demonstrated through a case study on the launch vehicle conceptual design of the first and second-stage separation system. The results indicate that the proposed method can automatically extract information from data resources to construct a knowledge graph. Furthermore, it can provide decision cases for design requirements through knowledge configuration, supporting decision-making. [ABSTRACT FROM AUTHOR]

Background: The prescription of Chinese herbal medicine (CHM) consists of multiple herbs that exhibit synergistic effects due to the presence of multiple components targeting various pathways. In clinical practice, the combination of Erchen decoction and Huiyanzhuyu decoction (EHD) has shown promising outcomes in treating patients with laryngeal squamous cell carcinoma (LSCC). However, the underlying mechanism by which EHD exerts its therapeutic effects in LSCC remains unknown., Methods: Online databases were utilized for the analysis and prediction of the active constituents, targets, and key pathways associated with EHD in the treatment of LSCC. The protein-protein interaction (PPI) network of common targets was constructed and visualized using Cytoscape 3.8.1 software. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to investigate the functional roles of core targets within the PPI network. Protein clustering was conducted utilizing the MCODE plug-in. The obtained results highlight the principal targets and pathways involved. Subsequently, clinical samples were collected to validate alterations in the levels of these main targets through Western blotting (WB) and immunohistochemistry (IHC). Furthermore, both in vivo and in vitro experiments were conducted to investigate the therapeutic effects of EHD on healing LSCC and elucidate its underlying mechanism. Additionally, to ensure experimental reliability and reproducibility, quality control measures utilizing HPLC were implemented for EHD herbal medicine., Results: The retrieval and analysis of databases in EHD medicine and LSCC disease yielded a total of 116 overlapping targets. The MCODE plug-in methods were utilized to acquire 8 distinct protein clusters through protein clustering. The findings indicated that both the first and second clusters exhibited a size greater than 6 scores, with key genes PI3K and ErbB occupying central positions, while the third and fourth clusters were associated with proteins in the PI3K, STAT3, and Foxo pathways. GO functional analysis reported that these targets had associations mainly with the pathway of p53 mediated DNA damage and negative regulation of cell cycle in terms of biological function; the death-induced signaling complex in terms of cell function; transcription factor binding and protein kinase activity in terms of molecular function. The KEGG enrichment analysis demonstrated that these targets were correlated with several signaling pathways, including PI3K-Akt, FoxO, and ErbB2 signaling pathway. On one hand, we observed higher levels of key genes such as P-STAT3 , P-PDK1 , P-Akt , PI3K , and ErbB2 in LSCC tumor tissues compared to adjacent tissues. Conversely, FOXO3a expression was lower in LSCC tumor tissues. On the other hand, the key genes mentioned above were also highly expressed in both LSCC xenograft nude mice tumors and LSCC cell lines, while FOXO3a was underexpressed. In LSCC xenograft nude mice models, EHD treatment resulted in downregulation of P-STAT3, P-PDK1, PI3K, P-AKT, and ErbB2 protein levels but upregulated FOXO3a protein level. EHD also affected the levels of P-STAT3, P-PDK1, PI3K, P-AKT, FOXO3a, and ErbB2 proteins in vitro: it inhibited P-STAT3, P-AKT, and ErbB2, while promoting FOXO3a; however, it had no effect on PDK1 protein. In addition, HPLC identified twelve compounds accounting for more than 30% within EHD. The findings from this study can serve as valuable guidance for future experimental investigations., Conclusion: The possible mechanism of EHD medicine action on LSCC disease is speculated to be closely associated with the ErbB2/PI3K/AKT/FOXO3a signaling pathway., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Evidence of the advantages of Coptidis Rhizoma (CR) for the treatment of ulcerative colitis (UC) is accumulating. However, research revealing the targets and molecular mechanisms of CR against UC is scarce. In this research, a bioinformatics analysis was performed to carry out the physicochemical properties and biological activities of phytochemicals in CR and analyze the binding activities, targets, biological functions and mechanisms of CR against UC. This research shows that the CR's key phytochemicals, which are named Coptisine, Berberrubine, Berlambine, Berberine, Epiberberine, Obacunone, Worenine, Quercetin, (R)-Canadine, Magnograndiolide, Palmatine and Moupinamide, have ideal physicochemical properties and bioactivity. A total of 1,904 potential phytochemical targets and 17,995 UC-related targets are identified, and we finally acquire 233 intersection targets between key phytochemicals and disease. A protein-protein interaction network of 233 common targets was constructed; and six hub targets were acquired with a degree greater than or equal to median, namely TP53, HSP90AA1, STAT3, ESR1, MYC, and RELA. The enrichment analysis suggested that the core targets may exert an impact on anti-inflammatory, immunoregulatory, anti-oxidant and anti-fibrosis functions mainly through the PI3K/ART signaling pathway, Th17 differentiation signaling pathway, inflammatory bowel disease signaling pathway, etcetera. Also, a molecular docking analysis shows that the key phytochemicals have strong affinity for binding to the core targets. Finally, the interaction network of CR, phytochemicals, targets, GO functions, KEGG pathways and UC is constructed. This study indicates that the key phytochemicals in CR have superior drug likeness and bioactivity, and the molecular mechanism of key phytochemicals against UC may be via the signaling pathway mentioned above. The potential and critical pharmacological mechanisms provide a direction for future research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yang, Hua, Chen, Zheng, Wu, Qin and Huang.)