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Background: Denglao Qingguan decoction (DLQGD) has been extensively utilized for the treatment of colds, demonstrating significant therapeutic efficacy. Human Coronavirus 229E (HCoV-229E) is considered a crucial etiological agent of influenza. However, the specific impact and underlying mechanisms of DLQGD on HCoV-229E remain poorly understood. Methods: Active ingredients and targets information of DLQGD were collected from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), literature search, and Swiss ADEM database. The Genecard database was used to collect HCoV-229E related targets. We built an “ingredient-target network” through Cytoscape. Protein - Protein interaction (PPI) networks were mapped using the String database. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) were enriched using the DAVID database. Then, we used molecular docking techniques to verify the binding activity between the core compounds and the core gene targets. Finally, in vitro experiments were conducted to validate DLQGD's antiviral activity against HCoV-229E and assess its anti-inflammatory effects. Results: In total, we identified 227 active components in DLQGD. 18 key targets involved in its activity against HCoV-229E. Notably, the core active ingredients including quercetin, luteolin, kaempferol, β-sitosterol, and apigenin, and the core therapeutic targets were CXCL8, RELA, MAPK14, NFKB1, and CXCL10, all associated with HCoV-229E. KEGG enrichment results included IL-17 signaling pathway, Toll-like receptor signaling pathway, RIG-I-like receptor signaling pathway and so on. The core active ingredients and the core therapeutic targets and Human Aminopeptidase N (ANPEP) all showed good binding activity by molecular docking verification. In vitro, DLQGD exhibited anti-HCoV-229E activity and anti-inflammatory effects. Conclusion: Our study suggests that DLQGD has both effects of anti-HCoV-229E and anti-inflammatory. The core active ingredients (quercetin, luteolin, kaempferol, β-sitosterol, apigenin) and the core therapeutic targets (CXCL8, RELA, MAPK14, NFKB1, CXCL10) may play key roles in the pharmacological action of DLQGD against HCoV-229E.

A benzofuroquinolinium derivative that exhibits excellent cell division inhibitory effect was discovered through cell-based screening approach. This compound possesses potent antimicrobial activity against both Gram-positive and Gram-negative bacteria including the drug-resistant strains. In addition, this compound is able to restore MRSA susceptibility to beta-lactam antibiotics. The biochemical results suggest that the compound inhibits bacterial cell division through the disruption of GTPase activity and the polymerization of FtsZ, which is probably the mechanism of antibacterial activity. Keywords: Bacterial resistance, Antibacterial activity, FtsZ inhibitor

A large number of extracts of medicinal plants or natural products shows beneficial to combat obesity. In the present work, a new flavonoid named (2S,1″R,2″R)-4′-hydroxy-7-methoxy-6-(1,2,3-trihydroxy-3-methyl-butyl)-flavanone (1), along with seven known compounds (2–8) were isolated from the seeds of Cullen corylifolium. Their structures, including the absolute configurations, were determined by the analysis of comprehensive spectroscopic data and computational calculation methods. All isolates were evaluated for their diacylglycerol acyltransferase (DGAT) inhibitory activity. Compounds 1–4 exhibited different level of DGAT1 inhibitory activity with IC50 values ranging from 28.2 ± 1.1 to 127.3 ± 1.9 μM. In addition, 45 flavonoids which be evaluated for DGAT inhibitory activity were summarised and potential structure–activity relationships were discussed. [ABSTRACT FROM AUTHOR]

In this article, a review focusing on the frost resistance of recycled coarse aggregate concrete (RAC) and the bond performance of RAC with rebar under freeze–thaw environment is carried out. The results show that there are still some controversies about the advantages and disadvantages of the frost resistance of RAC, and many influencing factors have not been considered. The mass of the RAC pullout specimens shows a trend of first increasing and then decreasing after freeze‒thaw cycles. The failure modes of the RAC pullout specimens after freeze‒thaw cycles include pullout failure, pullout-splitting failure, splitting failure, and rebar yielding failure. The bond performance of RAC with rebar shows a degradation trend after freeze‒thaw cycles, mainly in the decrease in bond strength and the increase in bond slip. The bond performance of RAC specimens is inferior to that of natural aggregate concrete specimens after freeze‒thaw cycles. The bond strength prediction models and the bond–slip constitutive relation prediction models of RAC with rebar after freeze‒thaw cycles have been summarized to ensure that engineers can better understand their applicability. The bond stress distribution between the RAC and rebar in the anchoring area is not uniform and constantly changes with the number of freeze‒thaw cycles. The degradation mechanism of the bond performance of RAC with rebar after freeze‒thaw cycles is analyzed.

The effect of pollutants on flux during the treatment of desulfurization wastewater by polyvinylidene fluoride（PVDF） membranes were investingated. Then，the pioneer pollutants and dominant pollutants causing flux changes at different periods in the treatment process were determined. The flow rate playd a dominant role in the distribution of the membrane fouling layer. A three-dimensional single-phase computational fluid dynamics（CFD） method was used to evaluate the flow state in the membrane module system，while SEM，X-ray energy dispersive spectrometer（SEM-EDS），and FTIR were used to analyze the distribution，composition and structure of pollutants on the membrane surface in the horizontal and vertical directions in different fouling periods. It was found that the change in membrane flux is divided into two main phases： a slowly decreasing phase and a rapidly decreasing phase， and the distinct flux variation in the two phases were attributed to differences in the dominant pollutants. Organic pollutants were the pioneer pollutants that lead to a slow decline in flux in the early stage，and mineral scaling was the dominant factor in the rapid decline of flux in the later stage. Organic pollutants mainly included humic acid and fulvic acid， which first deposited on the membrane surface during the membrane distillation process through hydrophobic-hydrophobic interaction with the membrane surface， causing a slow decrease in flux. Mineral contaminants， mainly calcium sulfate， nucleate and crystallize in the bulk solution as the concentration process， and grew rapidly on the membrane surface resulting in a rapid decrease in flux.

In order to accurately measure and analyze energy efficiency of traction systems, especially in the current absence of relevant standard references, this article presents an energy efficiency measurement system developed based on the requirements of IEC 62888-2:2018 for electric energy testing and GB/T 25117.1-2010 for torque and speed measuring instruments, taking the traction system of electric multiple units (EMUs) as the research object. To improve measurement accuracy, a purpose-made high-voltage acquisition board with isolation is designed to directly collect the output voltage signal of the 27.5 kV transformer and a pulse-type output torque-speed sensor to measure the mechanical parameters of the traction motor, enabling synchronous collection of both electrical and mechanical parameters. Through experiments conducted with standard signal sources, it is verified that the measurement accuracy of system energy consumption surpasses the standard requirement by 1.5%. Furthermore, regarding measurement of mechanical parameters, the torque accuracy exceeds the standard requirement by 0.5%, while the speed accuracy surpasses it by 0.1%. Meanwhile, in order to verify the system accuracy in dynamic energy consumption measurement, a high-precision power analyzer and this measurement system were used to simultaneously measure the energy consumption of the traction system with the same track data, revealing a relative error of less than 1%

In the rockfall prevention and control project, the reinforced concrete (RC) slab and sand (gravel soil) soil cushion layer are commonly used to form the protection structure, thereby resisting the rockfall impact. Considering that the oversized deformation of the cushion layer under impact load using the finite element simulation cannot converge, this article establishes a numerical calculation model using smoothed particle hydrodynamics–finite-element method coupling (SPH–FEM). First, the standard Lagrange finite-element mesh is established for the whole model using ABAQUS, and then the finite-element mesh of the soil cushion layer is converted to SPH particle at the initial moment of the calculation, and finally the calculation results are solved and outputted. The results indicate that, compared with the results of the outdoor rockfall impact test, the relative errors of the rockfall impact force and the displacement of the RC slab are within 10%, which proves the rationality of the coupling algorithm; moreover, in terms of the numerical simulation, the SPH–FEM coupling algorithm is more practical than the finite element for reproducing the mobility of the rockfall impacting the sand and soil particles. In addition, at an impact speed of less than 12 m·s−1, the cushion layer is able to absorb more than 85% of the impact energy, which effectively ensures that the RC slab is in an elastic working state under small impact energy and does not undergo destructive damage under large impact energy; the peak impact force of the rockfall is approximately linear with the velocity, and the simulated value of the peak impact force is basically the same as that of the theoretical value of Hertz theory; the numerical simulation is good for reproducing the damage process of the RC slab in accordance with the actual situation. The SPH–FEM coupling algorithm is more justified than the FEM in simulating the large deformation problem, and it can provide a new calculation method for the design and calculation of the rockfall protection structure.

Due to recycled aggregate concrete technology, sustainable resource utilization can be achieved, but the weak frost resistance of this type of concrete affects its application in cold regions. Using waste polypropylene fibers as reinforcing materials can improve the mechanical properties and durability of concrete. This study explores the influence of waste polypropylene fiber on the frost resistance durability and microstructure of recycled brick aggregate (RA) concrete. The results show that with the increase in freeze–thaw cycles, the mass of the concrete first increases and then decreases, while its relative dynamic elastic modulus and compressive strength gradually decrease. After 60 freeze–thaw cycles, the maximum mass loss, maximum relative dynamic elastic modulus loss, and maximum compressive strength loss of the RA concrete are 1.73, 45.1, and 73.7%, respectively. Waste fiber (WF) can improve the frost resistance of concrete, as demonstrated by the obvious reduction in mass loss, relative dynamic elasticity modulus loss, and compressive strength loss, which are 0.11, 33.0, and 64.0%, respectively, after 60 freeze–thaw cycles. The action mechanism of WF on the frost resistance of RA concrete is revealed, and the life prediction model of RA concrete with WF under freeze–thaw conditions is established.

One new polyacetylene glycoside eprostrata Ⅰ (1), together with seven known compounds (2–8), were isolated from Eclipta prostrata. Their structures were elucidated on the basis of spectroscopic and physico-chemical analyses. All the isolates were evaluated inhibitory activity on DGAT in an in vitro assay. Compounds 1–8 were found to exhibit inhibitory activity of DGAT1 with IC50 values ranging from 74.4 ± 1.3 to 101.1 ± 1.1 μM. [ABSTRACT FROM AUTHOR]

This paper studies the method of constructing high order recombined multinomial tree based on fast Fourier transform (FFT), and applies multinomial tree option pricing under the Lévy process. First, the Lévy option pricing model and Fourier transform are introduced. Then, the network model based on FFT (Markov chain) is presented. After that, a method of constructing a recombined multinomial tree based on FFT is given. It is proved that the discrete random variables corresponding to the multinomial tree converge to the Lévy distributed continuous random variable. Next, we obtain the European option pricing formula of FFT multinomial tree pricing, and apply the reverse iteration method to the American option pricing. Finally, under the Jump-diffuse process, the difference between the computational accuracy and computational efficiency of the Semi-analytical solution of European Option and Merton European Call Option which are priced under FFT is compared. The results show that the method of constructing a high-order recombined multinomial tree based on FFT has very high calculation precision and calculation speed, which can solve the problem of traditional risk-neutral multinomial tree construction and it is a promising pricing method for derivative products.

Based on the one-factor CIR interest rate model, the pricing of Sherpa Target Redemption Notes (STARN) with early-excise features is investigated in this paper. Firstly, the characteristics of Sherpa target redemption notes were described and the partial differential equation was proposed. Secondly, both non-arbitrage jump conditions on the coupon date and early-excise policy on the redemption date were provided; furthermore, the boundary conditions of partial differential equations were also discussed. Thirdly, a numerical method for solving the partial differential equation was obtained based on the control volume in the theory of finite volume by making use of the upwind weighting scheme to avoid the numerical oscillation phenomenon. Finally, the sensitivity of the model parameters was analyzed. The results show that the STARN value decreases rapidly with the increase in short-term interest rates, furthermore, when short-term interest rates reached a turning point the rate of decline slowed. As volatility increases, the value of the Notes is increased; increasingly as the proportion redeemed is large, STARN value increases.