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Recently, two-dimensional (2D) nanostructures, such as graphene and few-layer MoS[subscript 2], have been applied to wide fields based on their intriguing performances, and they contribute to developments of clean energy, biomedicine, and environmental protection. The synthesis of 2D nanostructures involves chemistry, materials, and biology-associated interdisciplinary knowledge. Nevertheless, desired strategies that can be comprehensively and safely achieved by undergraduates or academic trainees are largely restricted considering the uses of toxic and pyrophoric reagents, high-risk manipulation, expensive instruments, and a time-consuming test period. Herein, chemically fundamental experiments are integrated with scientific frontiers, achieving the development of undergraduate's experimental projects based on up-to-the-minute academic results. In order to promote the high-efficient study and eliminate the risks among our learners, the virtual simulation courses are well-integrated, and students can independently complete the synthesis of 2D MoS[subscript 2] nanomaterials without the face-to-face guidance of mentors. Significantly, several characteristics are equipped in this project: (1) Students can master the uses of oxygen-sensitive, moisture-sensitive reagents and skills for operating high-risk reactions via the virtual system; (2) Universal preparation approaches of 2D nanomaterials, based on the Schlenk technique, are presented; (3) Students' understanding of MoS[subscript 2] monolayer characterization, properties, and applications is remarkably increased. This project aims at inspiring students' understanding for scientific frontiers, improving their academic and innovative skills, as well as expanding their advanced perspective.

Owing to their exceptional piezoelectric effects, piezoelectric materials play a crucial role in high-end technologies and contribute significantly to the national economy. Bismuth layer-structured ferroelectrics (BLSFs) possess high Curie temperatures, making them a focal point of research in high-temperature piezoelectric sensor devices. However, their poor piezoelectric performance and low direct-current (DC) electrical resistivity hinder their effective deployment in high-temperature applications. To overcome these shortcomings, we employed composition optimization by partially substituting bismuth ions with rare-earth praseodymium ions. This approach enhances the piezoelectric performance and improves the DC electrical resistivity by preventing the loss of volatile bismuth ions and stabilizing the bismuth oxide layer (Bi2O2)2+, thereby reducing the concentration of oxygen vacancies. Consequently, we achieved a large piezoelectric constant d33 of 23.5 pC/N in praseodymium-substituted Bi5Ti3FeO15, which is three times higher than that of pure Bi5Ti3FeO15 (7.1 pC/N), along with a high Curie temperature TC of 778 °C. Additionally, the optimal composition of 4 mol% praseodymium-substituted Bi5Ti3FeO15 exhibits good thermal stability of electromechanical coupling characteristics up to 300 °C. This study holds promise for a wide array of high-temperature piezoelectric applications and has the potential to accelerate the development of high-temperature piezoelectric sensor technologies.

Colistin used to be regarded as the last-resort treatment for the infection caused by multidrug-resistant gram-negative bacteria. However, the emergence and widespread of mcr-1 seriously reduce the clinical effectiveness of colistin, constituting a serious threat to global public health. Due to the difficulties in the development of new antibiotics, restoring antibiotic susceptibility with adjuvants is undoubtedly a rational option. As naturally occurring compounds, resveratrol and capsaicin could be extracted from many natural plants, due to various antimicrobial properties, they have received significant attention. Herein, the synergistic activity of colistin combined with resveratrol and capsaicin against mcr-1-positive Escherichia coli were investigated by checkerboard method and time-killing assays. The in-depth molecular mechanisms were elucidated by scanning electron microscopy, fluorescent probe experiments, transcriptome and metabolome analysis. Molecular docking assay was taken to analyse potential interactions between resveratrol/capsaicin and MCR-1. Finally, the in vivo efficacy of combined therapy against mcr-1-positive Escherichia coli was assessed. Our results demonstrated that colistin combined with resveratrol and capsaicin acted synergistic activity against mcr-1-positive Escherichia coli both in vivo and in vitro. Further mechanistic studies showed that the combined therapy could exacerbate cell membrane damage, increase membrane permeability, disrupt the homeostasis of PMF, inhibit ATP synthesis, and efflux pump activity. In addition, the combined therapy could inhibit central carbon metabolism, and reduce tricarboxylic acid cycle and oxidative phosphorylation. Moreover, molecular docking assay revealed resveratrol/capsaicin could bind to MCR-1 stably. Our study indicated that colistin in combination with resveratrol and capsaicin as a novel therapy could provide a trustworthy foundation to establish the treatment plan for mcr-1-positive Escherichia coli.

Partial coalescence is a key factor contributing to the instability of crystalline oil-in-water emulsions in products like dressings and sauces, reducing shelf life. The intrinsic characteristics of semi-crystalline droplets, including solid fat content, fat crystal arrangement, and polymorphism, play a pivotal role in influencing partial coalescence, challenging prevention efforts even with emulsifiers like amphiphilic proteins. High-intensity ultrasound (HIU) has emerged as an efficient and cost-effective technology for manipulating bulk fat crystallization, thereby enhancing physical properties. This study specifically investigates the impact of HIU treatment on fat crystallization on protein-stabilized crystalline emulsions, utilizing palm olein stearin (POSt) as the lipid phase and sodium caseinate (NaCas) as the surfactant under various HIU powers (100, 150, 200, 300, and 400 W). Results show that increasing HIU power maintained the interfacial potential (−20 mV) provided by NaCas in the emulsions without significant differences. Higher HIU power induced the most stable polymorphic form (β) in the emulsions. Engagingly, the emulsions at 200 W exhibited better storage stability and slower partial coalescence kinetics. Semi-crystalline globules had more uniform and integral crystal clusters that were distributed tangentially near the droplet boundary, perhaps attributed to intermediate subcooling (40.4 °C) at 200 W. The acoustic energy of HIU significantly translates into thermal effects, influencing subcooling degrees as a dominant factor affecting crystallisation in the emulsions. This study establishes ultrasonic crystallization as a novel strategy for modifying the stability of emulsions containing fat crystals.

The inerting technology is a common means to prevent fires in goaf of coal mine, in which adsorption capacity is the key index to measure the inerting effect. Therefore, this paper obtained the coal spontaneous combustion (CSC) stage of Qianyingzi coal mine through programmed heating experiments, and determined the physical adsorption stage temperature (below 323.15 K) matching the actual environment. The oxidation characteristics of coal samples with different adsorption degrees were further studied by adsorption experiment and TG-DSC test. The results indicate that the combustion activation energy of coal samples follows the sequence of second-stage adsorption coal > dried coal > raw coal > first-stage adsorption coal. This implies that the CO2 saturated adsorption can exert a specific inhibitory impact on coal combustion. Therefore, the index of the saturation adsorption capacity (SAC) was proposed to evaluate the inerting effect. We further studied the adsorption capacity of coal at different ratios of CO2/N2 by molecular simulation under different pressures (0–5 MPa). The results show that CO2 dominates in both single-component adsorption and competitive saturated adsorption. The average of ratios (AOR) and average of differences (AOD) threshold are determined. The priority of SAC is obtained in the order of single-component (CS), CO2/N2 mixture ratio at 4:6 (C4:6), CO2/N2 mixture ratio at 2:8 (C2:8) from largest to smallest. Furthermore, a fuzzy optimization method for injection ratio of CO2/N2 under different pressures was established. During dynamic changes in environmental pressure, it is appropriate to inject CO2 separately at 0.2–2.5 MPa. At 3 MPa, a mixture of CO2/N2 at a ratio of 2:8 is the best for prevent fires in goaf. Similarly, an inert gas with a CO2/N2 ratio of 4:6 is injected at 3–5 MPa.

This paper addresses the practical issue of load frequency control (LFC) in multi-area power systems with degraded actuators and sensors under cyber-attacks. A time-varying approximation model is developed to capture the variability in component degradation paths across different operational scenarios, and an optimal controller is constructed to manage stochastic degradation across subareas simultaneously. To assess the reliability of the proposed scheme, both Monte Carlo simulation and particle swarm optimization techniques are utilized. The methodology distinguishes itself by four principal attributes: (i) a time-varying degradation model that broadens the application from single-area to multi-area systems; (ii) the integration of physical constraints within the degradation model, which enhances the realism and practicality compared to existing methods; (iii) the sensor suffers from fault data injection attacks; and (iv) an optimal controller that leverages particle swarm optimization to effectively balance reliability and system performance, thereby improving both stability and reliability. This method has demonstrated its effectiveness and advantages in mitigating load disturbances, achieving its objectives in just one-third of the time required by established benchmarks. The case study validates the applicability of the proposed approach and demonstrates its efficacy in mitigating load disturbance amidst stochastic degradation in actuators and sensors under FDIA cyber-attacks.

The LB films prepared through the Langmuir–Blodgett (LB) technique are of significant importance for the fabrication of functional films such as optoelectronic materials and sensors. In this study, 9,9-bis (4-(2-hydroxy-ethoxy) phenyl) fluorene (BPEF) and 9,9-bis [3-phenyl-4-(β-hydroxy-ethoxy) phenyl] fluorene (BBPEF) were combined with saffron T (ST), methylene blue (MB) and Rhodamine B (RhB) dyes by LB technique to prepare ordered composite films. The nanostructures and morphologies of the composite films were analyzed by transmission electron microscopy (TEM) and atomic force microscopy (AFM). It was found that the films exhibited distinct aggregation morphologies. The UV-VIS absorption spectra showed that the concentration of dye molecules had a significant effect on the spectral characteristics. The contact Angle test shows that the prepared composite films are hydrophobic. The photovoltaic conversion performance of LB composite films was studied by transient photocurrent response experiments. It was found that BPEF/dye and BBPEF/dye composite films exhibited significant responses in photocurrent. In particular, BPEF/RhB and BBPEF/RhB composite films demonstrated excellent photoresponsive performance. This study used LB technology in combination with BPEF and BBPEF to demonstrate enhanced photocurrent and stable performance of LB film, which provided ideas for expanding the application range of materials.

Ultrasonic flotation is widely used as an efficient mineral separation method. Its efficiency is related to the adhesion behavior between fine particles and flotation bubbles, which can be influenced by the bubbles’ movement behavior. This paper used two immersed ultrasonic vibration plates to generate ultrasonic action and investigated the effect of ultrasonic action on the rising process of flotation bubbles. The distribution, aggregation and fusion, velocity, and other characteristics of bubbles generated by different needle apertures were studied by experimental and simulation methods. The results showed that a 0.4 mm needle produced bubbles that were more evenly spaced and more uniform in size and shape. The ultrasonic action can make the bubbles aggregate together and reduce the bubble rise velocity, as well as prolong their time in the flotation process at the same time. It is beneficial to the sufficient collision and adhesion behavior between flotation bubbles and particles, eventually improving the efficiency of mineral flotation.

Introduction: We here describe a new method for distinguishing authentic Bletilla striata from similar decoctions (namely, Gastrodia elata, Polygonatum odoratum, and Bletilla ochracea schltr).Methods: Preliminary identification and analysis of four types of decoction pieces were conducted following the Chinese Pharmacopoeia and local standards. Intelligent sensory data were then collected using an electronic nose, an electronic tongue, and an electronic eye, and chromatography data were obtained via high-performance liquid chromatography (HPLC). Partial least squares discriminant analysis (PLS-DA), support vector machines (SVM), and back propagation neural network (BP-NN) models were built using each set of single-source data for authenticity identification (binary classification of B. striata vs. other samples) and for species determination (multi-class sample identification). Features were extracted from all datasets using an unsupervised approach [principal component analysis (PCA)] and a supervised approach (PLS-DA). Mid-level data fusion was then used to combine features from the four datasets and the effects of feature extraction methods on model performance were compared.Results and Discussion: Gas chromatography–ion mobility spectrometry (GC-IMS) showed significant differences in the types and abundances of volatile organic compounds between the four sample types. In authenticity determination, the PLS-DA and SVM models based on fused latent variables (LVs) performed the best, with 100% accuracy in both the calibration and validation sets. In species identification, the PLS-DA model built with fused principal components (PCs) or fused LVs had the best performance, with 100% accuracy in the calibration set and just one misclassification in the validation set. In the PLS-DA and SVM authenticity identification models, fused LVs performed better than fused PCs. Model analysis was used to identify PCs that strongly contributed to accurate sample classification, and a PC factor loading matrix was used to assess the correlation between PCs and the original variables. This study serves as a reference for future efforts to accurately evaluate the quality of Chinese medicine decoction pieces, promoting medicinal formulation safety.

To explore the macro–micro coal oxidation characteristics for the purpose of preventing coal spontaneous combustion and achieving efficient coal conversion and utilization, the enclosed coal oxidation characteristics of KunNing coal sample (KN) under 25–70 °C were investigated. KN coal molecular models were constructed based on analysis and testing results of X-ray Photoelectron Spectroscopy (XPS), Carbon-13 Nuclear Magnetic Resonance Spectroscopy (13C NMR), Fourier Transform Infrared Spectroscopy (FTIR) and other techniques. The pyrolysis processes of coal-oxygen reaction systems with different oxygen contents were simulated using ReaxFF force field. The results show that the oxygen consumption rate, CO release rate, CO2 release rate and oxidation heat release intensity of coal increase exponentially with rising temperature. The ratio of aromatic bridge carbon to peripheral carbon in KN coal molecular structure is 0.08, and the molecular formula is C149H76O15N2S2. In the later stage of the experimental and molecular dynamics simulation processes, the CO content decreased while the growth rate of CO2 increased. Different indicator gases exhibit varied responses to oxygen content. The C-atom labeling and traceback results for the four indicator gas molecules demonstrate that CO2 mainly comes from aldehyde, hydroxyl, carboxyl and methoxy groups in coal molecules, CO is primarily generated from esters, phenols, carbonyls, C2H2 is predominantly derived from ring-opening and cracking of cycloalkanes, and the source of C2H4 is related to cycloalkanes and alcohols.

The increasing prevalence of obesity globally, which as well as affecting people's daily lives and increasing the risk of obesity complications, also threatens the health of animal organisms simultaneously. It’s been reported that Yi-Qi-Yang-Yin-Ye had remarkable efficacy in the treatment of obesity. The specific underlying mechanism of action of Yi-Qi-Yang-Yin-Ye in treating obesity, however, remains ambiguous. Therefore, the innovative approach, which is network pharmacology combined with molecular docking and molecular dynamics simulations, was employed in the current research to explore the potential mechanism and promote further development in the treatment of obesity. The active ingredients and related targets of Yi-Qi-Yang-Yin-Ye and related targets of obesity were summarized from extensive public databases. Furthermore, network topology analysis and pathway enrichment analysis were performed to explore the complicated interactions between drug and targets. Finally, accurate validation methods composed of molecular docking and molecular dynamics simulations were conducted to elucidate the binding affinity of Yi-Qi-Yang-Yin-Ye with obesity-related targets. As a result, 13 main active ingredients and 5 core targets of Yi-Qi-Yang-Yin-Ye against obesity in rats were acquired through primary screening of network topology analysis. Pathway enrichment analysis demonstrated that intersectional targets were involved in multiple signaling pathways, where PI3K-Akt signaling pathway, MAPK signaling pathway, and Insulin resistance were the main pathways of Yi-Qi-Yang-Yin-Ye in treating obesity in rats. Finally, molecular docking indicated that the seven critical active ingredients displayed great binding affinity to the hub targets. Furthermore, molecular dynamics simulations further screened and obtained that five critical active ingredients acting on the Mapk1 target for Yi-Qi-Yang-Yin-Ye against obesity in rats. The innovative approach and the results achieved have further contributed to and revealed the molecular mechanisms for treating obesity, providing an alternative for treating obesity in animals and humans.

The reduced graphene oxide (rGO) exhibits outstanding electrical conductivity and a high specific surface area, making it a promising material for various applications. Fe2O3 is highly desirable due to its significant theoretical capacity and cost-effectiveness, high abundance, and environmental friendliness. However, the performance of these r-GO/Fe2O3 composite electrodes still needs to be further improved, especially in terms of cycle stability. The composite of Fe2O3 anchored on N-doped graphene with inside micro-channels (Fe2O3@N-GIMC) was used to be efficiently prepared. Because the inside channels can furnish extra transmission pathways and absorption websites and the interconnected structure can efficaciously forestall pulverization and aggregation of electrode materials. In addition, N doping is also beneficial to improve its electrochemical performance. Thus, it demonstrates exceptional sodium storage characteristics, including notable electrochemical activity, impressive initial Coulombic efficiency, and favorable rate performance. The optimized Fe2O3@N-GIMC indicates outstanding discharge capacity (573.5 mAh g−1 at 1 A g−1), significant rate performance (333.6 mAh g−1 at 8 A g−1), and stable long-term cycle durability (308.9 mAh g−1 after 1000 cycles at 1 A g−1, 200.8 mAh g−1 after 4000 cycles at 1 A g−1) as a sodium-ion battery anode. This presents a new approach for preparing graphene-based high-functional composites and lays a stable basis for further expanding its application field.

The surface modification of amorphous carbon nanospheres (ACNs) through templates has attracted great attention due to its great success in improving the electrochemical properties of lithium storage materials. Herein, a safe methodology with toluene as a soft template is employed to tailor the nanostructure, resulting in ACNs with tunable surface pores. Extensive characterizations through transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption/desorption isotherms elucidate the impact of surface pore modifications on the external structure, morphology, and surface area. Electrochemical assessments reveal the enhanced performance of the surface-pore-modified carbon nanospheres, particularly ACNs-100 synthesized with the addition of 100 μL toluene, in terms of the initial discharge capacity, rate performance, and cycling stability. The interesting phenomenon of persistent capacity increase is ascribed to lithium ion movement within the graphite-like interlayer, resulting in ACNs-100 experiencing a capacity upswing from an initial 320 mAh g−1 to a zenith of 655 mAh g−1 over a thousand cycles at a rate of 2 C. The findings in this study highlight the pivotal role of tailored nanostructure engineering in optimizing energy storage materials.

The film temperature distribution of the valve plate pair in axial piston pumps affects its lubrication, leakage, and friction. In order to investigate the film temperature distribution of the valve plate pair in axial piston pumps, a test platform was constructed including three displacement sensors for the oil film thickness and eleven thermocouples for the film temperature distribution of the valve plate pair. An accurate film shape model of the valve plate pair was built according to the three-point film thickness test data. Based on the film shape model, the film temperature model of the valve plate pair was developed considering the viscous oil temperature characteristics, the energy loss caused by leakage and viscous friction in the film, and the heat conduction among the oil, cylinder block, and valve plate. The influence of different swash plate tilt angles and operating pressures on the valve plate film temperature was studied. The test results indicate that the film temperature of the valve plate pair increases as the working pressure and swash plate tilt angle increase. The theoretical and experimental absolute errors of the film temperature in the circumferential range [−60°, 60°] of the valve plate high-pressure side are less than 3.5 °C. As the swash plate tilt angle varies from 12° to 16° and working pressure from 3 MPa to 7 MPa, the minimum film thickness position and the maximum temperature point move accordingly in the circumferential range [−15°, 5°] of the valve plate pair.

To meet the requirements of miniaturization and low power consumption of portable instruments, a set of lower computer control system of portable quadrupole mass spectrometry was designed. The new control system was developed based on Xilinx spartan-6 series field programmable gate array (FPGA) platform. A single FPGA chip was used to replace the cumbersome architecture of traditional multiple chip combinations. The original W5500\MCU\DSP\DDR and other functional chips on the main control circuit board were removed, and the scanning, control, acquisition, storage, data processing, high-speed transmission and other functions realized by these chips were integrated into the same FPGA chip. The control system mainly communicated with the lower computer through the upper computer. The lower computer controlled the DAC voltage to scan the quadrupole, and at the same time linked the 16 bit ADC to collect data. The collected data was processed by some columns of algorithms, and then a large amount of data was accumulated and compressed, stored in the chip. Finally, the whole spectrum data was integrated according to the frame format and uploaded to the upper computer for displaying. The lower computer control system also integrated tuning control, feedback control, high voltage control and other functional modules. The difficulty in the design of the whole system lied in the high utilization of chip resources, which required a reasonable allocation of various chip resources and a balance in performance, speed and area. Compared with the existing miniaturized quadrupole mass spectrometry control system, the new control system not only saved the chip cost on the premise of unchanged function and performance, but also saved about 2.7 W in the power consumption of the master hardware board, which was about 37% of the power consumption of the original board, and reduced about 20 cm2 in the area of the master hardware board, which was about 10% of the area of the original board. The performance of the portable quadrupole mass spectrometer lower computer control system was fully verified by the 25 volatile organic compounds (VOCs) mixed standard test experiment, and was successfully applied in the portable quadrupole mass spectrometer. This design has high technology portability and practical value for similar miniaturized instruments. At this stage of the design, it is not possible to integrate all the functions of the instrument and realize a real single-chip lower computer control system, and the integrated functional modules need to be further optimized. Under the demand of miniaturization and low power consumption of portable instruments, the concept and design of integration will go further and further, and will slowly and truly achieve simple substitution for cumbersome, single substitution for combination, so as to make the concept of portability to the extreme and obtain the maximum value with the least consumption.

Abstract Increasing evidence shows that abnormal copper (Cu) metabolism is highly related to many diseases, such as Alzheimer's disease, Wilson's disease, hematological malignancies and Menkes disease. Very recently, cuproptosis, a Cu‐dependent, programmed cell death was firstly described by Tsvetkov et al. in 2022. Their findings may provide a new perspective for the treatment of related diseases. However, the concrete mechanisms of these diseases, especially cuproptosis, remain completely unclear, the reason of which may be a lack of reliable tools to conduct highly selective, sensitive and high‐resolution imaging of Cu in complex life systems. So far, numerous small‐molecular fluorescent probes have been designed and utilized to explore the Cu signal pathway. Among them, fluorescence turn‐on probes greatly enhance the resolution and accuracy of imaging and may be a promising tool for research of investigation into cuproptosis. This review summarizes the probes developed in the past decade which have the potential to study cuproptosis, focusing on the design strategies, luminescence mechanism and biological‐imaging applications. Besides, we put forward some ideas concerning the design of next‐generation probes for cuproptosis, aiming to tackle the main problems in this new field. Furthermore, the prospect of cuproptosis in the treatment of corresponding diseases is also highlighted.

In order to master the temperature and dissipation law of the porous media-CO2 system, the distribution of temperature and adsorption field in porous media during intermittent CO2 injection was studied by using self-developed adsorption device and experimental platform of diffusion seepage. The results show that the distribution of high temperature in porous media is isotropic. The effect of CO2 on the temperature field mainly occurs in the self-heating stage of coal, and the high temperature area moves towards gas injection port. The gas migration rate is the highest in the first gas injection. The cooling rate decreases with the increase of gas injection times. Combined with the logistic function relationship between adsorption capacity and temperature, the porous medium CO2 adsorption field was constructed, and it was found that the adsorption field is stable under low temperature oxidation. Therefore, temperature variation mechanism of confined space porous media-CO2 system was established, and quadrilateral of coal spontaneous combustion prevention was proposed. By analyzing the heat transfer process of coal-CO2 system, the thermodynamic entransy dissipation was introduced.

Conductive hydrogels are highly attractive for biomedical applications due to their ability to mimic the electrophysiological environment of biological tissues. Although conducting polymer polythiophene-poly-(3,4-ethylenedioxythiophene) (PEDOT) and polystyrene sulfonate (PSS) alone exhibit high conductivity, the addition of other chemical compositions could further improve the electrical and mechanical properties of PEDOT:PSS, providing a more promising interface with biological tissues. Here we study the effects of incorporating crosslinking additives, such as glycerol and sodium trimetaphosphate (STMP), in developing interpenetrating PEDOT:PSS-based conductive hydrogels. The addition of glycerol at a low concentration maintained the PEDOT:PSS conductivity with enhanced wettability but decreased the mechanical stiffness. Increasing the concentration of STMP allowed sufficient physical crosslinking with PEDOT:PSS, resulting in improved hydrogel conductivity, wettability, and rheological properties without glycerol. The STMP-based PEDOT:PSS conductive hydrogels also exhibited shear-thinning behaviors, which are potentially favorable for extrusion-based 3D bioprinting applications. We demonstrate an interpenetrating conducting polymer hydrogel with tunable electrical and mechanical properties for cellular interactions and future tissue engineering applications.

Caprazamycin is a nucleoside antibiotic that can interrupt bacterial peptidoglycan biosynthesis, but the biosynthesis of caprazamycin is not fully understood yet. Here, the authors characterize five key enzymes from caprazamycin/muraymycin gene cluster, particularly nonheme αKG-dependent enzyme Cpz10 as a β-hydroxylase that recruits two iron atoms and leads to caprazamycin formation.

The Euphorbiaceae plant Euphorbia neriifolia L. is distributed widely in India, Thailand, Southeastern China, and Taiwan and used as a carminative and expectorant to treat several inflammation-related diseases, such as gonorrhoea, asthma, and cancer. In the course of our search for potential anti-inflammatory agents from the titled plant, 11 triterpenes from the stem of E. neriifolia were isolated and reported in our previous endeavor. Given its rich abundance in triterpenoids, the ethanolic extract in this follow-up exploration has led to the isolation of additional eight triterpenes, including six new euphanes—neritriterpenols H and J–N (1 and 3–7)—one new tirucallane, neritriterpenol I (2), and a known compound, 11-oxo-kansenonol (8). Their chemical structures were elucidated on the basis of spectroscopic data, including 1D- and 2D NMR, and HRESIMS spectra. The absolute stereochemistry of neritriterpenols was determined by single-crystal X-ray diffraction analysis, ICD spectra, and DP4+ NMR data calculations. Compounds 1–8 were also evaluated for their anti-inflammatory activity by using lipopolysaccharide (LPS)-stimulated IL-6 and TNF-α on RAW 264.7 macrophage cells. Intriguingly, the euphane-type triterpenes (1 and 3–8) showed an inhibitory effect on LPS-induced IL-6 but not on TNF-α, while tirucallane-type triterpene 2 showed strong inhibition on both IL-6 and TNF-α.

Studies in the past few years have shown that simple salts, such as pyridinium salts and imidazole salts, have excellent antibacterial activity. However, their application in drugs and agrichemicals development has been limited due to their high toxicity. In this study, we found that synthesized target compounds with pyridinium salt unit A1 and B6 displayed excellent anti-Xac (Xanthomonas. axonopodis pv. citri) and Xoo (Xanthomonas oryzae pv. oryzae) activity, with EC50 values of 7.67 μg/mL and 1.37 μg/mL, respectively. On searching for a toxicity reduction strategy, an ion exchange method was adopted to obtain a new type of various organic acid-decorated pyridinium salt derivatives containing with glycyrrhetinic acid framework, and their structure was characterized by FTIR and 1H NMR. Furthermore, bioassays and toxicity tests were used to show that these organic acid-exchanged compounds not only exhibited lower toxicity to plants but also had excellent antibacterial activity towards virulent phytopathogenic bacteria, especially compound D3, which provided an EC50 of 1.60 μg/mL toward Xoo. Subsequently, the pot experiments determined that compound D3 exhibited suitable protective and curative activities for the management of rice bacterial leaf blight at 200 μg/mL, with control efficacies of 54.09% and 38.50%, respectively. In addition, studies evaluating potential antibacterial mechanisms suggested that apoptosis was responsible for the antibacterial behavior of the target compounds. Overall, this study proved that the ion exchange method was a feasible strategy to reduce the toxicity of pyridinium salts and was promising for use in the development of novel antimicrobial agents.

Natural products play an irreplaceable role in the treatment of SARS-CoV-2 infection. Nevertheless, the underlying molecular mechanisms involved remain elusive. To better understand their potential therapeutic effects, more validation studies are needed to explore underlying mechanisms systematically. This study aims to explore the potential targets of action and signaling pathways of cepharanthine for the treatment of COVID-19. This study revealed that a total of 173 potential targets of action for Cepharanthine and 86 intersectional targets for Cepharanthine against COVID-19 were screened and collected. Gene Ontology enrichment analysis suggested that inflammatory, immune cell and enzyme activities were the critical terms for cepharanthine against COVID-19. Pathway enrichment analysis showed that five pathways associated with COVID-19 were the main signaling pathways for the treatment of COVID-19 via cepharanthine. Molecular docking and molecular dynamics simulations suggested that 6 core targets were regarded as potential targets for cepharanthine against COVID-19. In brief, the study demonstrates that cepharanthine may play an important role in the treatment of SARS-CoV-2 infection through its harmonious activity against SARS-CoV-2 pathways and multiple related targets. This article provides valuable insights required to respond effectively to concerns of western medical community.

This paper focuses on determining the authenticity and identifying the species of Fritillariae cirrhosae using electronic nose, electronic tongue, and electronic eye sensors, near infrared and mid-level data fusion. 80 batches of Fritillariae cirrhosae and its counterfeits (including several batches of Fritillaria unibracteata Hsiao et K.C. Hsia, Fritillaria przewalskii Maxim, Fritillaria delavayi Franch and Fritillaria ussuriensis Maxim) were initially identified by Chinese medicine specialists and by criteria in the 2020 edition of Chinese Pharmacopoeia. After obtaining the information from several sensors we constructed single-source PLS-DA models for authenticity identification and single-source PCA-DA models for species identification. We selected variables of interest by VIP value and Wilk’s lambda value, and we subsequently constructed the three-source fusion model of intelligent senses and the four-source fusion model of intelligent senses and near-infrared spectroscopy. We then explained and analyzed the four-source fusion models based on the sensitive substances detected by key sensors. The accuracies of single-source authenticity PLS-DA identification models based on electronic nose, electronic eye, electronic tongue sensors and near-infrared were respectively 96.25%, 91.25%, 97.50% and 97.50%. The accuracies of single-source PCA-DA species identification models were respectively 85%, 71.25%, 97.50% and 97.50%. After three-source data fusion, the accuracy of the authenticity identification of the PLS-DA identification model was 97.50% and the accuracy of the species identification of the PCA-DA model was 95%. After four-source data fusion, the accuracy of the authenticity of the PLS-DA identification model was 98.75% and the accuracy of the species identification of the PCA-DA model was 97.50%. In terms of authenticity identification, four-source data fusion can improve the performance of the model, while for the identification of the species the four-source data fusion failed to optimize the performance of the model. We conclude that electronic nose, electronic tongue, electronic eye data and near-infrared spectroscopy combined with data fusion and chemometrics methods can identify the authenticity and determine the species of Fritillariae cirrhosae. Our model explanation and analysis can help other researchers identify key quality factors for sample identification. This study aims to provide a reference method for the quality evaluation of Chinese herbs.

This activity explores an alternative use of a superabsorbent polymer known as a water absorbing material. A dilute solution of CuCl[subscript 2] is treated with a small piece of unused disposable diaper containing superabsorbent sodium polyacrylates. The polymer is used for the removal of Cu[superscript 2+] ions from the solution. The Cu[superscript 2+] ions in the solution are sequestered through ion exchange with the sodium ions of the insoluble polymer. The solution loses its color, and the polymer gels turn blue. The Cu[superscript 2+] solutions before and after the treatment are further tested with soap solution to confirm the action of the polymer. (Contains 2 figures and 1 scheme.)

The presence of surface trap states (STSs) is one of the key factors to affect the electronic and optical properties of quantum dots (QDs), however, the exact mechanism of how STSs influence QDs remains unclear. Herein, we demonstrated the impact of STSs on electron transfer in CdSe QDs and triplet-triplet energy transfer (TTET) from CdSe to surface acceptor using femtosecond transient absorption spectroscopy. Three types of colloidal CdSe QDs, each containing various degrees of STSs as evidenced by photoluminescence and X-ray photoelectron spectroscopy, were employed. Time-resolved emission and transient absorption spectra revealed that STSs can suppress band-edge emission effectively, resulting in a remarkable decrease in the lifetime of photoelectrons in QDs from 17.1 ns to 4.9 ns. Moreover, the investigation of TTET process revealed that STSs can suppress the generation of triplet exciton and effectively inhibit band-edge emission, leading to a significant decrease in TTET from CdSe QDs to the surface acceptor. This work presented evidence for STSs influence in shaping the optoelectronic properties of QDs, making it a valuable point of reference for understanding and manipulating STSs in diverse QDs-based optoelectronic applications involving electron and energy transfer.

Gel fracturing fluid is the optimum fracturing fluid for proppant suspension, which is commonly applied in deep reservoir hydraulic fracturing. The content of polymers and crosslinkers in gel fracturing fluid is usually high to meet the needs of high-temperature resistance, leading to high costs and reservoir permeability damage caused by incomplete gel-breaking. In this paper, a supramolecular reinforced gel (SRG) fracturing fluid was constructed by strengthening the supramolecular force between polymers. Compared with single network gel (SNG) fracturing fluid, SRG fracturing fluid could possess high elasticity modulus (G′ = 12.20 Pa) at lower polymer (0.4 wt%) and crosslinker (0.1 wt%) concentrations. The final viscosity of SRG fracturing fluid was 72.35 mPa·s, meeting the temperature resistance requirement of gel fracturing fluid at 200 °C. The gel-breaking time could be extended to 90–120 min using an encapsulated gel breaker. Gel particles are formed after the gel fracturing fluid is broken. The median particle size of gel particles in the SRG-breaking solution was 126 nm, which was much smaller than that in the industrial gel (IDG) breaking fluid (587 nm). The damage of the SRG-breaking solution to the core permeability was much less than the IDG-breaking solution. The permeability damage of cores caused by the SRG-breaking solutions was only about half that of IDG-breaking solutions at 1 mD.

In this paper, we aim to address the challenge of airflow interference during fault detection in high-speed train bogies by introducing a flow field and investigating the characteristics of the sound field distribution of critical components under its influence. This approach overcomes the limitation observed in previous studies that ignored the impact of the flow field. Furthermore, we evaluate and compare various layouts for inter-track acoustic sensor arrays. The study results demonstrate that the axle box and gearbox are primarily affected by frequency bands above 200 Hz, while the motor is mainly influenced by frequencies above 150 Hz. Moreover, the motor is most significantly impacted by vehicle speed, followed by the gear box and finally the shaft box. When altering the vibration frequency of the sound source, there is a decreasing trend in minimum sound pressure level with increasing frequency. Additionally, the gradient of the sound pressure level change at three locations (motor, gear box, and axle box) exceeds that of both vehicle speed variation and vibration intensity of the sound source. By adjusting the vibration intensity of the sound source, similar gradients are observed for both maximum and minimum values of sound pressure level at these three locations. Therefore, vibration intensity has a consistent effect on changes in sound pressure level at these three places but only influences its magnitude. The aforementioned methods can be employed for the analysis of wind noise and structural noise, thereby offering novel insights for future advancements in noise reduction processing.

Exosomes were enriched from plasma by ultracentrifugation, precipitation, and membrane-based approaches for yield and purity. Using the four isolation approaches, particles with mode sizes within the expected range (50–200 nm) can be isolated. By protein estimation, polymer precipitation resulted in a maximum yield (5610.59 ± 51.189 µg/mL), followed by membrane affinity (471.57 ± 12.16 µg/mL), ultracentrifugation (440.22 ± 11.71 µg/mL) and filter + ultracentrifugation (235.47 ± 13.27 µg/mL). By total RNA estimation, the yield of polymer precipitation (3.26 ± 0.42 ng/mL) was higher than that of ultracentrifugation (1.52 ± 0.06 ng/mL), filter + ultracentrifugation (1.21 ± 0.25 ng/mL) and membrane affinity (1.44 ± 0.14 ng/mL). The purity of exosomal preparations was determined as the ratio of the particle number to protein and of protein to RNA. According to the ratio of the particle number to protein concentration, the “purity” of the polymer precipitation method was similar to that of the membrane affinity method and higher than that of ultracentrifugation and filter + ultracentrifugation. When the ratio of RNA to protein was used, the “purity” of the polymer precipitation method was lower than that of the membrane affinity method. Differential methods can be employed to enrich specific exosome subpopulations. The steps of the methods affect the particle number, protein content, and even exosomal purity. The best extraction and evaluation methods for exosomes need to be selected in the laboratory according to their experimental needs.

Background: The monitoring and removal of heavy metal ions in wastewater will effectively improve the quality of water and promote the green and sustainable development of ecological environment. Using more efficient adsorption materials and more accurate detection means to treat heavy metal ions in water has always been a research focus and target of researchers.Method: A novel titania nanomaterial was modified with sulfhydryl group (nano TiO2-SH) for detection and adsorption of heavy metal ions in water, and accurately characterize the adsorption process using Surface-Enhanced Raman Spectroscopy (SERS) and other effective testing methods.Results: The maximum adsorption efficiency of nano TiO2-SH for the Hg2+, Cd2+, Pb2+ three heavy metal ions reached 98.3%, 98.4% and 98.4% respectively. And more importantly, after five cycles of adsorption and desorption, the adsorption efficiency of nano TiO2-SH for these three metal ions is still above 96%.Conclusion: These results proved the nano TiO2-SH adsorbent has great potential in practical water pollution purification.

Modifying biodegradable poly (butylene adipate-co-terephthalate) (PBAT) plastic with inorganic fillers is critical for improving its overall performance, lowering the costs, and expanding its application scope. The chemical modification method for the inorganic filler determines the application performance of PBAT composites. In this work, gas—solid fluidization method was developed as a simple, efficient, and scalable strategy for chemically modifying CaCO3 filler. The modified CaCO3 filler was mixed with PBAT and melt extruded to prepare biodegradable PBAT/CaCO3 composites. The characterization results show that gas—solid fluidization method combines the traditional wet modification method’s excellent modification effect with the scalability of the traditional dry modification method. The effects of modification methods and amount of CaCO3 filling on the crystallinity, mechanical, and rheological properties of PBAT/CaCO3 composites were compared. The results demonstrated that PBAT/CaCO3 composites containing 30% gas—solid fluidization modified CaCO3 could still maintain excellent overall performance. As a result, this work provides a simple, efficient, and scalable method for chemically modifying inorganic fillers and preparing biodegradable composites.

In this study, ultrasound-assisted alkaline hydrolysis was used to extract polyphenols from pitahaya peel. The effects of sonication time, ultrasonic density, NaOH concentration and the liquid–material ratio on the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of the extracts were studied. The composition and content difference of the extracts were analyzed and the inhibitory effect of α-amylase and α-glucosidase was measured. The results of single-factor analysis showed that when the sonication time was 45 min, the ultrasonic density was 32 W/L, the NaOH solution concentration was 6 M and the liquid–material ratio was 30 mL/g, the release of phenolic compounds was the largest and the antioxidant activity was the strongest. An UPLC-QTOF-MS/MS method was used to analyze the components and contents of the extracts. We found that there was a great difference in the component content of the free polyphenol extract and the bound polyphenol extract. From the results, we concluded that there was a strong correlation between the type and content of phenolic compounds and antioxidant activities, indicating that phenolic compounds were the main compounds of these biological activities. Moreover, the bound polyphenol extracts showed a significant inhibitory effect on α-amylase and α-glucosidase was stronger than that of the free polyphenol extracts. In addition, scanning electron microscopy showed that ultrasound-assisted extraction is crucial to the destruction of the cell wall and the release of bound polyphenols. Therefore, the pitahaya peel has the potential for therapeutic, nutritional, and functional food applications, and ultrasound-assisted alkaline hydrolysis is an effective means to release phenolic compounds.

The catalytic treatment of wastewater serves as an effective way to solve the problem of water pollution, in which non-homogeneous Fenton catalysts are widely used. However, the activity enhancement of non-homogeneous Fenton catalysts still remains a great challenge. Herein, self-assembled BiFeO3/CeO2 nanocatalytic materials with different molar ratios were successfully fabricated by a suspension blending method, following which the structure evolution was determined by various characterizations. The catalytic degradation of methylene blue (MB), rhodamine B (RhB), and saffron T (ST) were performed over the BiFeO3/CeO2 nanocatalytic materials. It was found that the 0.2BiFeO3:0.8CeO2 nanocatalytic materials exhibited an 80.8% degradation efficiency for RhB. The 0.6BiFeO3:0.4CeO2 nanocatalytic materials reached 81.1% and 48.7% for ST and MB, respectively. The BiFeO3/CeO2 nanocatalytic materials also showed a good stability during several cycles. The combination of CeO2 with BiFeO3 led to an enhanced activity for dye degradation, probably due to the electron transfer from ≡Fe2+ to ≡Ce4+. This study provides a new approach to dye degradation by using Fenton catalytic systems.

In order to increase industrial production quality and efficiency, it is essential to understand how the aeration and no-aeration condition affects liquid and solid material mixing in the stirred tank. Due to complicated shear flows, the related mass-transfer mechanism confronts numerous difficulties. This paper put forward an improved computational fluid dynamics and discrete element method (CFD–DEM) modeling approach to explore the effect mechanism of aeration conditions on liquid–solid material mixing. Firstly, a mass-transfer dynamic model is set up with a volume of fluid and piecewise linear interface construction (VOF–PLIC) coupling strategy to explore flow modes and vorticity evolution trends under aeration control. Then, a self-developed interphase coupling interface is utilized to modify the coupling force and porosity of the porous media model in the DEM module, and random dispersion properties of the particle phase under non-aeration and aeration are obtained. Results show that the aeration and flow-blocking components transform fluid tangential speeds into axial and radial speeds, which can improve the material mixing quality and efficiency. The mixed flow field can reach a greater turbulent process under the impeller rotation, making the particles have an intensive disorder and complex flow patterns. The enhanced motion efficiency of the vortex clusters encourages their nesting courses and improves cross-scale mixed transport. It can serve as some reference for the three-phase flow mixing mechanism, vorticity distribution law, and particle motion solution and has a general significance for battery homogeneous mixing, biopharmaceutical processes, and chemical process extraction.

A resonant photoacoustic spectrometer (PAS) was developed for detecting trace atmospheric CH4. The sensitivity of the PAS was significantly increased via a Herriott-type multipass cell with a beam pattern concentrated in the cavity. The effective optical pathlength of the PAS can be optimized to 6.8 m with 34 reflections and a diameter of 6 mm. A distributed feedback diode laser at 1,653 nm was employed as the light source, and wavelength modulation spectroscopy was used for the 2nd harmonic signal to reduce the noise of the system. The resonant cell of PA and optimal modulation frequency were obtained by varying the measurements. In comparison with a single path, the sensitivity of the multipass strategy was improved 13 times. To evaluate the long-term stability and minimum detection limit (MDL) of the system, an Allan variance analysis was performed, and the analysis illustrated that the MDL accomplished 116 ppb at an average time of 84 s. The system was utilized for 2 days test campaign to validate the feasibility and robustness of the sensor. The system provides a promising technique for online monitoring of greenhouse gasses.

Graphical Abstract

Mesonaprocumbens Hemsley is a plant conventionally processed to provide popular food materials and herbal medicines in Asia. In this study, six triterpene acids, including five new ones (mesonaic acids D-H, 1–5), and one proximadiol-type sesquiterpene (7) were isolated from the methanolic extract of the air-dried M. procumbens. Chemical structures of 1‒7 were established by spectroscopic methods, especially 2D NMR techniques (1H–1H COSY, HSQC, HMBC, and NOESY) and HRESIMS. Concerning their biological activities, compounds 1, 2, 6, and 7 were examined manifesting high inhibition toward the pro-inflammatory NO production with EC50 values ranging from 12.88 to 21.21 µM, outrunning the positive control quercetin (24.12 µM). The mesoeudesmol B (7) identified from M. procumbens is the very first example, which exhibited high anti-inflammatory activity diminishing the level of the lipopolysaccharide-induced NO in RAW264.7 macrophage cells, thereby suppressing the secretion of pro-inflammatory cytokines TNF-α and IL-6 and the level of two critical downstream inflammatory mediators iNOS and COX-2.

Cortex Fraxini is an important traditional Chinese herbal medicine with various medical functions. Aesculin and aesculetin are the main effective components of Cortex Fraxini. The fluorescence signals of the two compounds have a high degree of overlap with each other, making quantitative analysis difficult with conventional analytical methods. In the present study, different chemometrics methods, including lasso regression (LAR), interval partial least squares (iPLS), and multidimensional partial least squares (N-PLS) methods, were employed and combined with excitation–emission matrix (EEM) fluorescence for the purpose of accurate quantification of aesculin and aesculetin in Cortex Fraxini samples. The most satisfactory results were obtained by using the N-PLS method based on the EEM spectra without scatterings, with correlation coefficient of calibration and prediction values higher than 0.9972 and 0.9962, respectively, root mean squared errors for calibration and prediction values lower than 0.0304 and 0.1165, respectively, and recovery values in the range of 83.32%–104.62%. The obtained credible models indicated that the N-PLS method combined with EEM spectra has the advantages of being green, low cost, and accurate and it is a good strategy for the determination of active compounds in complex samples. To further confirm the accuracy of the obtained results, the same samples were analyzed by the recognized ultra-performance liquid chromatography method.