最新刊期
卷 60 ， 期 3 ， 2021
- 摘要：As a newly emerging nanomaterial， silicon nanoparticle possesses many advantages in the application of biosensor. In recent years， silicon nanoparticles have been received widespread attention in biosensor， bioanalytical， and fluorescence probe. Herein， the functional modification， and application in fluorescence detection， biosensor， and imaging analytical of silicon nanoparticles were reviewed. Moreover， the future functional modification developments and application of silicon nanoparticles are also discussed.关键词：silicon nanoparticles;cell imaging;function modification;biosensor;fluorescence detection
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发布时间：2023-12-08
Invited review
- 摘要：Naoxintong Capsule is a traditional Chinese medicine formulation composed of 16 traditional Chinese medicines， such as Astragali Radix （Huangqi） and Salviae miltiorrhizae Radix et Rhizoma （Danshen）. It is clinically used to treat cardiovascular and cerebrovascular diseases with the functions of benefiting qi for activating blood circulation and promoting blood circulation for removing obstruction in collaterals. A number of clinical and basic studies have shown that Naoxintong Capsule possesses extensive pharmacological activities， such as anti-platelet aggregation， anti-thrombus， anti-inflammation， anti-atherosclerosis and improving metabolic disturbance. Metabolic disturbance is a common risk factor and causes most of cardiovascular and cerebrovascular diseases. This article reviewed the progress in the material basis， and effects and mechanisms of Naoxintong Capsule on metabolic disturbance and its related diseases， and proposed perspectives for its scientific intension and clinical application.关键词：Naoxintong Capsule;material basis;metabolic disturbance;cardiovascular and cerebrovascular diseases;effects and mechanisms
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发布时间：2023-12-08 - 摘要：Five known lignans including three 8，4′-oxyneolignans ［（-）-erythro-（7′E）-4，9-dihydroxy-3，3′，5′-trimethoxy-8，4′-oxyneolign-7′-en-9′-al （1）， （-）-erythro-guaiacylglycerol-β-O-4′-sinapyl ether （2）， and （7′E）-3，5，3′，5′-tetramethoxy-8，4′-oxyneolign-7′-ene-4，9，9′-triol （3）］， a benzofuran ［（+）-（7R，8S）-5-methoxydihydrodehydrodiconiferyl alcohol （4）］， and one furofuran ［syringaresinol （5）］ were isolated from the traditional Chinese medicine Selaginella doederleinii. Their structures were elucidated by HRMS and 1D and 2D NMR data. The inhibitory activities of 1-5 against thioredoxin reductase （TrxR） were evaluated， and three compounds showed moderate activities with IC50 values ranging from 10.1 to 20.2 μmol/L. Compounds 1-4 were isolated from S. doederleinii for the first time. In addition， it was found that the structures of ten known lignans ［2，6，2′，6′-tetramethoxy-4，4′-bis（2，3-epoxy-1-hydroxypropyl）biphenyl （Ⅰ）， griffilignan A （Ⅱ）， 2-hydroxy-3，2′，6′-trimethoxy-4′-（2，3-epoxy-1-hydroxypropyl）-5-（3-hydroxy-l-propenyl）biphenyl （Ⅲ）， 2-hydroxy-3，2′-dimethoxy-4′-（2，3-epoxy-1-hydroxypropyl）-5-（3-hydroxy-1-propenyl）biphenyl （Ⅳ）， 2，2′-dimethoxy-4-（3-hydroxy-l-propenyl）-4′-（1，2，3-trihydroxypropyl）diphenyl ethers （Ⅴ and Ⅵ）， （7΄R，8΄R）-2，2′-dimethoxy-4-（3-hydroxyl-propenyl）-4′-（1，2，3-trihydroxypropyl）biphenyl ether （Ⅶ）， utiline B （Ⅷ）， and rhemaneolignans A and B （Ⅸ and Ⅹ）］ were erroneously identified as the types of biphenylneolignans and 4，4′-oxyneolignans due to incorrect elucidation. By comparison of their NMR data with those of model compounds such as some reported synthetic products and the isolates （1-5）， the structures of Ⅰ-Ⅹ were revised as （+）-syringaresinol （5）， （+）-pinoresinol （6）， （-）-simulanol （7）， （-）-dehydrodiconiferyl alcohol （8）， （-）-threo-guaiacylglycerol-β-O-4′-coniferyl ether （9）， （+）-erythro-guaiacylglycerol-β-O-4′-coniferyl ether （10a）， （-）-erythro-guaiacylglycerol-β-O-4′-coniferyl ether （10b）， （+）-threo-guaiacylglycerol-β-O-4′-sinapyl ether （11）， （-）-threo-methyl 4-O-［2-hydroxy-2-（4-hydroxy-3-methoxyphenyl）-1-（hydroxymethyl）ethyl］ferulate （12）， and （+）-erythro-methyl 4-O-［2-hydroxy-2-（4-hydroxy-3-methoxyphenyl）-1-（hydroxymethyl）ethyl］ferulate （13）， respectively. So， it noteworthy that there is no evidence for the existence of the ten lignans in nature， and their revised structures are actually represented as the types of furofurans， benzofurans， and 8，4′-oxyneolignans， respectively.关键词：Selaginellaceae;Selaginella doederleinii;lignan;biphenylneolignan;structural revision
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发布时间：2023-12-08 - 摘要：The processed product of Aconiti Lateralis Radix Praeparata （PAC） is a traditional Chinese medicine with cardiac， anti-inflammatory， and rheumatoid arthritis activities. The diterpenoid alkaloids are the main active ingredients of PAC. In order to comprehensively analyze the composition of diterpenoid alkaloids in PAC and explore its potential and new compounds， this study used ultra-high-performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry （UPLC-Q-TOF -MS/MS） coupled with a GNPS （global natural products social molecular networking） strategy to quickly characterize the compositions of PAC. And the GNPS excavated new molecular weight to discover the unknown or trace natural products based on the characteristics of each cluster. A total of 123 compounds were characterized， including 21 diester diterpenoid alkaloids （DDAs）， 11 lipo alkaloids （Lipo-As）， 43 monoester diterpenoid alkaloids （MDAs）， 47 aminoalcohol-diterpenoid alkaloids （ADAs）， 1 polyester diterpenoid alkaloid （PDAs）. 34 of them were discovered for the first time. This study utilized a GNPS-based screening approach with a significant increase of efficiency for the discovery and identification of trace novel natural products. The results have expanded our understanding of the chemical material of PAC.关键词：UPLC-Q-TOF-MS/MS;the processed products of Aconiti Lateralis Radix Praeparata;global natural products social molecular networking（GNPS）;diterpenoid alkaloids
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发布时间：2023-12-08 - 摘要：Xiaochaihu Granule （XCHG） is a famous traditional Chinese medicine （TCM） firstly studied and developed by the Guangzhou Baiyunshan Guanghua Pharmaceotical Co.， LTD. The study aimed to investigate the biological target network and potential mechanisms of XCHG through network pharmacology techniques. The compounds and targets of XCHG were screened using TCMSP， PubMed， and UniProt databases. The protein-protein interaction network was analyzed by String and Cytoscape. The GO functions and KEGG pathways were enriched. The active component-target-pathway network of XCHG was established. The results showed that 82 active compounds and 242 potential targets were obtained in XCHG. Wherein， Quercetin， Kaempferol， Luteolin， Wogonin， Naringenin， 7-Methoxy-2-methyl isoflavone， Baicalein， Formononetin， Stigmasterol， and β-sitosterol were the main active compounds； VEGFA， JUN， MAPK3， AKT1， MMP9， IL6， ALB， PTGS2， CXCL8， and CASP3 were the key targets； Twenty key pathways were enriched， and 50% of them were closely related to antiviral effects， such as Human cytomegalovirus infection， Influenza A， Epstein-Barr virus infection， etc. Other major pathways include immune- and inflammation-related pathways such as PI3K-Akt pathway， MAPK pathway， TNF pathway， etc.， and apoptosis-related pathways such as Apoptosis pathway， etc. This study showed the advantages of XCHG in suppressing virus replication and viral infection， revealed the key targets and pathways in regulating immune and inflammatory response， and cell apoptosis. The results provided helpful references for XCHG’s mechanism explanation and clinical administration.关键词：Xiaochaihu Granule （XCHG）;biological target network;antiviral effect;inflammatory reaction;immune response;mechanism
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发布时间：2023-12-08 - 摘要：Based on the modern geoinformatics theory and techniques， 3D geological model provides a spatial perspective view of structures and attributes of geological bodies， which provides basic data and support for the design， development and decision-making of underground space. However， uncertainties， caused by the discretization and sparsity of observed data， complexity of geological body and randomness of modeling algorithm， strictly limit the effective application of the 3D geological model. Based on the data error of stratigraphic contacts， a function for uncertainty analysis of geological subsurface is built up in this study. The uncertainty analysis of geological structures is implemented with different perturbance conditions by the Monte Carlo simulation， in which the geological attribute probability （GAP） is used as simulating parameter. The concrete example of fault zone uncertainty at one of the stations of Guangzhou Metro illustrates that the proposed method of which the GAP is used as a parameter not only can integrate different types of data error， but also can connect geological attributes and spatial data error. The perturbance factor is the key to impact the shape of fault surface in the unsampled area， and the suite of GAP models represents the spatial relationship between the fault and metro engineering. Therefore， the proposed method can effectively guide the design and construction of metro engineering.关键词：fault zone;uncertainty;geological attribute probability;3D geological model;metro engineering
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发布时间：2023-12-08 - 摘要：Synthetic HPHT gem-quality diamond is an important high-tech material. The necessary catalyst in its growing process controls the product quality and also contains important clues to track the forming environment and mechanism of natural diamond. In this paper， We collected 218 gem-quality diamond samples， which came from three major manufacturers of high temperature and high pressure （HPHT） diamond in China （denoted by HH， Z， J， respectively）， and compared their morphological and spectroscopic characteristics. Among which， nine specific samples were selected to explore the synthetic catalyst components by analyzing the effects of catalyst-caused impurity，for the purpose to reveal the influence of catalyst change on the synthetic diamond during the growing process of the state-of-the-art of gem-quality HPHT diamond producing in China. The results are summarized into three aspects：1） The catalysts of the colorless gem-quality HPHT diamonds mainly contain metal elements of Fe and Co， while those of the yellow diamond mainly contain metal elements of Ni， Mn and Co， indicating that the main nitrogen remover maybe Ti， Al and Cu elements. 2） Adding a single non-metallic element into the catalyst makes more inclusions in the HPHT diamond with triangle pits and defects on crystal surface. The synergistic doping of nonmetallic catalyst can improve the quality of diamond crystal. 3） Fe-Co system is more suitable for growing Ⅱa type gem-quality diamonds than Fe-Ni system； Co replacing Ni can reduce the Ni-related defects in crystals and improve the color grade of synthetic diamonds. These results have significance for tracking the forming environment of natural diamond and the identification of synthetic gem-quality HPHT diamond.关键词：synthetic HPHT diamond;catalyst;growth environment;quality influence
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发布时间：2023-12-08 - 关键词：terrestrial LiDAR;point clouds processing;DEM;3D scene building;active fault
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发布时间：2023-12-08 - 摘要：Water ecological civilization construction is one of the most important parts of Chinese ecological city. Evaluating construction conditions in pilot cities is helpful to summarize the experience and provide guidelines for later construction. In this study， 26 indices were established for Dachong town in Zhongshan city， Guangdong province， based on evaluation guide for water ecological civilization construction （SL/Z 738-2016）. With the help of statistical data in 2017， both the equal weight evaluation method and the non-equal weight analytic hierarchy process fuzzy comprehensive method were used to compare the effect of water ecological civilized city construction in the research area. The results show that： 1） under the equal weight evaluation， the score for water ecological civilization construction in the study area is 52 （full score 104）， and the relatively low score is mainly caused by the serious water pollution， which led to a zero value for water environment related indices； 2） Although the assessed score using the non-equal weight analytic hierarchy process （AHP） fuzzy comprehensive method is similar to the equal weight evaluation method， the differentiated weight shows that the water ecology，except for water environment， is the main influencing factor leading to a low score for the study area.The analysis suggests that if the water ecological civilization construction of the town is expected to reach the basic standard， the water environment indicators should reach the level Ⅱ of the guidelines， which should be paid attention to in the follow-up construction.关键词：ecological construction;water ecology;evaluation index;analytic hierarchy process （AHP） fuzzy comprehensive evaluation method;Zhongshan city
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发布时间：2023-12-08 - 摘要：Physical processes of liquid film， such as flow， breakup， and rivulets， are closely related to lots of practical engineering issues such as the passive containment cooling systems （PCCS） of nuclear power.Researchers have been paying more and more attentions on these physical processes recently. As for the PCCS liquid film flow of AP600， the numerical methods were applied in this paper to calculate the influences of liquid film breakup on coverage rate. In this study， the one-dimensional Eulerian liquid film model was adopted to calculate the PCCS liquid film flow， and the EI-Genk and Saber models were adopted to simulate the liquid film breakup process. The results show that the thickness of the PCCS liquid film varies a lot at the upper dome of the facility， which could easily induce liquid film breakup and rivulets. By studying the relationship between liquid film coverage and PCCS flow rate， the flow rate meeting safety standards is obtained.关键词：film flow;film breakup;rivulets;PCCS
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发布时间：2023-12-08 - 摘要：Based on shallow wave diffraction theory， the wave potential solutions to first order cnoidal wave diffraction by semi-infinite and finite-length vertical thin wall breakwater are derived respectively by applying the eigenfunction expansion approach and stationary phase method. The dimensionless maximum wave forces and diffracted wave surfaces for two different kind of breakwaters are analytically calculated. Results demonstrate that when the finite-length thin wall breakwater has enough large length， the diffracted wave surface distribution around the end of breakwater and its wave force have almost same values as that of semi-infinite breakwater， which gives an effective mutual verification of two analytical solutions. The wave effect results from cnoidal wave theory for two kind of breakwaters are obviously larger than those predicted by small amplitude wave theory in same shallow water conditions. The variation of incident wave angle， ratio of breakwater arm length，water depth and shallow water wave characteristic may affect the wave. Practical diffracted wave forces on two kind of breakwaters will all increase as the shallow water wave characteristic parameter value increases.关键词：cnoidal wave;semi-infinite vertical thin wall breakwater;finite-length vertical thin wall breakwater;wave force;diffracted wave surface
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发布时间：2023-12-08 - 摘要：This paper proposes a long-term traffic status prediction model based on a spatio-temporal eigenvector in order to solve the problem of long-term traffic status prediction. Based on the analysis of the spatio-temporal correlation of traffic status changes， the model constructs the spatio-temporal eigenvector that represents the law of traffic status variation， including time axis feature， historical average traffic status feature， recurrent congestion feature and historical average traffic status feature of upstream and downstream roads. The prediction results of the single roads show that the model has a good prediction performance. The accuracy of all-day prediction is about 90% and the accuracy of peak hour prediction is about 80%. Furthermore， compared with single time features， the proposed spatio-temporal eigenvector can significantly improve the prediction accuracy. The prediction results of multiple roads show that the SVM prediction method based on spatio-temporal has a good universality. The average accuracy of allday prediction is about 95% and the average accuracy of peak hour prediction is about 88%.关键词：long-term prediction;support vector machine;traffic status;spatio-temporal eigenvector
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发布时间：2023-12-08 - 摘要：Wind load inversion based on measured response can provide reliable wind load data for building design and health monitoring. In this paper， the time historical of wind load was fitted based on Davenport wind velocity spectrum.The dynamic equation was established based on the modal superposition method. The dynamic response of the structure was solved by the fine integration method， and the positive problem was analyzed to obtain the linear relationship between the acceleration response and the load. Furthermore， wind load inversion is a typical inverse problem， which aims to identify the wind load of a structure by the measured acceleration. Augmented Kalman filter is a common load inversion method which takes the load as a state variable. The load increment at each time step is random， thus requires additional covariance information. In practice， non-random load increment and unknown covariance information can lead to a large load identification error. For this reason， this paper proposes a stepwise least square algorithm， which takes the equation of state and the least square of the observation equation of each time step as the objective function to gradually identify the load. The advantage is that it does not involve covariance information of the load. The result of the example shows that the recognition result of the stepwise least square algorithm is better than that of the augmented Kalman filter with good anti-noise performance.关键词：wind load;Load identification;least square method;Kalman filter
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发布时间：2023-12-08 - 摘要：Lightning strike is an important ignition source of forest fires. As the global warming， forest lightning fire is becoming more and more serious. In this paper， the relationship between the position of lightning strike and ground combustible matter was studied， and the breakdown voltages of three typical conifer beds were measured by the impulse voltage generator. The results show that there is little difference in the breakdown voltage between Xinjiang spruce needle bed and Siberian pine needle bed. The breakdown voltage of Pinus massoniana Lamb. needle bed is the smallest. In addition， the effect of ash content on the resistance of soil was studied. The results show that the higher the ash content is， the lower the resistance is. The site after prescribed burning is more vulnerable to lightning strike. The impulse current generator was used to simulate the lightning strike process， and it is found that the combustible matter can be ignited and produce mars splashing under the action of impulse current. Combined with the hypothesis of Taylor， the formation process of forest lightning fire was discussed. Finally， the lightning critical ignition characteristics of typical vegetation structure （tree and grass） were compared， and it is found that the grass is more likely to be ignited by lightning than the wood chip.关键词：lightning fire;prescribed burning;breakdown voltage;impulse current
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发布时间：2023-12-08 - 摘要：To solve the most unfavorable seismic response of arch ribs during seismic excitation of continuous beam-arch composite structures and reduce the peak value of structural response， this paper introduces the layout and mechanical parameters of lead rubber anti-seismic bearing with the background of Nanzhonghuan Bridge in Taiyuan City. The calculation method is used to analyze the damping effect of the cross-section area， hardening ratio and isolation bearing size of the continuous beam-arch combination structure. The results show that the lead rubber bearing can effectively reduce the internal force response and displacement response of the main arch rib. The maximum displacement isolation ratio of each control section of the main arch rib is different between 35.8%~54.7%， and the maximum internal isolation is between 32.3%~64.4% under different lead core cross-sectional areas， different hardening ratios and different isolation bearing sizes. Different mechanical characteristic parameters have various damping effects on the bridge. Compared with the hardening ratio and the size of the isolation bearing， the lead core diameter plays a greater role in the structural isolation ratio； due to the arrangement of the isolation bearing and the original design bearing， the existence of the structural displacement limit is limited， while the minimum internal vibration isolation rate of the arch is only 4.8%； when other mechanical parameters are consistent and the lead core diameter D = 180 mm， the hardening ratio α = 0.154， the diameter of the support is 1 200 mm the best shock absorption effect.关键词：continuous beam arch combination structure;lead rubber bearing;mechanical characteristic parameters;shock absorption design
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发布时间：2023-12-08 - 摘要：The equilibrium investment strategy for a DC pension plan with derivative trading under the mean-variance criterion is considered. That is to say， a representative member of the DC pension plan is allowed to invest not only in a risk-free asset and a stock， but also in a derivative. The stock price is described by a stochastic volatility model. Within the game theoretic framework， the analytic expressions of the equilibrium investment strategies and the corresponding equilibrium efficient frontiers are obtained in two cases， with and without the derivative asset. Finally， numerical examples show that the stochastic volatility and risk premium have significant impact on the equilibrium efficient frontiers， and the equilibrium efficient frontier of the case with derivative is always better than the equilibrium efficient frontier of the case without derivative.关键词：derivatives;DC pension plan;equilibrium investment strategy;stochastic volatility
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发布时间：2023-12-08 - 摘要：A class of MSIQRS epidemic models with age structure was discussed， and the expressions of basic reproductive number
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发布时间：2023-12-08 - 摘要：A food chain unstirred chemostat model with toxins is investigated. A priori estimate of positive solutions is given by the maximum principle and the super and sub-solution method. Then by using the bifurcation theory of simple eigenvalues， the global branch of positive solutions is studied， and the sufficient and necessary conditions for the existence of positive solutions are obtained. Finally， the stability of positive bifurcating solutions is discussed by means of the perturbation theory of linear operators and the stability theory of bifurcation solutions. The research results indicate that the species can coexist and positive solutions are stable under the influence of toxins and appropriate conditions.关键词：unstirred chemostat model;bifurcation theory;global branch;stability
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发布时间：2023-12-08 - 摘要：Based on Lipschitz condition of activation functions， a class of fractional-order recurrent neural networks is discussed. Combining with inequality technique， the existence， uniqueness and finite- time-stability of the solutions for this model are studied. An example is given to ensure the main results in the last.关键词：recurrent neural networks;fractional-order;finite-time-stability
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发布时间：2023-12-08
Research articles
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