最新刊期
      卷 62 ， 期 3 ， 2023

        Invited review

      • CHEN Xiaotong,ZHAO Wenlong,SUN Linyu,WANG Wentao,CHEN Yueqin
        Vol. 62, Issue 3, Pages: 1-13(2023) DOI: 10.13471/j.cnki.acta.snus.2022E049
        摘要：It was long presumed that non-coding RNAs （ncRNAs） are lacking in protein-coding potential. However， recent advances in technology and tools have led to an important finding that a number of small open reading frames （sORFs） were found in different kind of ncRNAs， and their translated products have been termed sORF encoded peptides （SEPs） or micropeptides. Some micropeptides have been confirmed to exist stably in cells and play important roles independently of their source RNA. In this review， we summarize the identification methods of micropeptides derived from ncRNAs， the types of RNA that can encode micropeptides， and focus on the functional micropeptides found in diseases and plants. The purpose of the review is to provide a thought on the screening and identification of micropeptides， and provide new ideas for micropeptides as potentials for drug development or crop yield improvement.  
        关键词：non-coding RNA;micropeptide;non-canonical translation;identification methods;regulation mechanism   
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        发布时间：2023-11-01

        Research articles

      • FAN Caiyuan,MENG Fanbao,LIU Jinfeng
        Vol. 62, Issue 3, Pages: 14-24(2023) DOI: 10.13471/j.cnki.acta.snus.2022D047
        摘要：Monitoring and distinguishing the development of microcracks in deformed rocks are helpful to understand the likely brittle failure mechanisms， which is essential for preventing rock engineering disasters. In this study， uniaxial compression experiments were performed on sandstone and granite samples to study the failure processes inversed by acoustic emission （AE） monitoring. Macroscopically， the sandstone samples exhibited a shear faulting mode while the granite samples an axial splitting mode. These two modes， however， cannot be clearly distinguished using the traditional AE methods via hits and the b value， as these parameters can reflect the frequency and energy level characteristics of elastic energy released during the cracking process only. Therefore， we propose a crack cumulative summation curve method， following the RA-AF crack classification method， which can successfully inverse and distinguish the possible different microcracking processes in deformed rock from the pure tensile microcrack development （k=1） to the pure shear microcrack development （k=-1） according to the variance of curve slope k value （i.e.， -1~1）. Inversed results show that during deformation to brittle failure， the tensile microcracks development first dominates the deformation of sandstone （i.e.， k=0.66）， followed by a transition between the development of the tensile and shear microcracks （i.e.， k decreased to 0）， and finally by strongly developed shear microcracks （i.e.， k decreased to -0.37 from 0） dominating shear faulting. In contrast， the granite sample showed a macroscopic axial splitting mode， as no strong development of shear microcracks was observed， i.e.， k remains greater than 0， decreasing to 0.5 from 0.83. The combined effects suggest these two failure modes can be clearly distinguished by strongly developed shear microcracks in rock near failure. Microscopic observation performed on the failure sandstone clearly illustrated wing tensile cracks in the shear fracture zone. This supports our inversed results that macro shear fracturing of sandstone was formed upon the initiation of the tensile microcracks， followed by the development of the shear microcracks. This suggests AE monitoring using our proposed crack cumulative summation curve method can properly distinguish the development of microcracks and accordingly failure modes in the deformed rocks， and may be used for further study on understanding the failure process of rocks upon complex loading conditions.  
        关键词：acoustic emission （AE）;microcracks development;crack mode;failure process;failure mechanism   
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        发布时间：2023-11-01
      • WANG Jing,SUN Xian,XIA Dong,WU Zhipeng,SUN Liye,LI Zhili
        Vol. 62, Issue 3, Pages: 25-34(2023) DOI: 10.13471/j.cnki.acta.snus.2022D035
        摘要：With global warming， extreme winds， particularly short-term extreme winds are becoming more frequent and cause great damage to constructions. In this paper， an extremum model and a CFD method are used to study the wind resistance grades in different directions of constructions on the island near Zhuhai， to provide fundamental information for architectural design and reduce disasters. Because of the limitation of automatic observations， the Gumbel distribution is used to fit the extreme winds in 16 directions of the Zhuhai Station； then the gust coefficients and relevant data from nearby automatic stations are used to calibrate the data in the study area. It is resolved that the annual extreme wind speed of once in 50 years and once in 100 years is 76.1 m/s and 83.5 m/s， respectively； the directions with the maximum winds are East-Southeast （ESE）， East （E）， and East-Northeast （ENE）. Furthermore， we simulated the effects of extreme winds from 16 different directions using CFD， it is found that the layout， shape， and height of constructions all affect the wind speed. The required wind resistance grades of constructions on the island are determined： the D4 area needs the highest wind resistance grade which is over the Beaufort wind force scale of 17； the D2 area requires the lowest wind resistance grade， which is about the Beaufort scale of 14 to 15.  
        关键词：constructions on island;extreme wind in 16 directions;recurrence period;wind resistance grade   
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        发布时间：2023-11-01
      • PANG Ying,CHEN Sheng,HU Junjun,CHEN Haiqin,HUANG Chaoying
        Vol. 62, Issue 3, Pages: 35-46(2023) DOI: 10.13471/j.cnki.acta.snus.2022D049
        摘要：To explore the influence of background error covariance constructed by different control variable schemes （CV5， CV6， and CV7） on radar data assimilation in the WRFDA assimilation system， a warm-sector torrential rainfall in Guangzhou on May 7， 2017 was taken as a case study in this paper. The single and radar observation data assimilation （DA） tests （Exp-CV5， Exp-CV6， and Exp-CV7） of three control variable schemes were carried out， and the results of the assimilation tests were diagnosed and analyzed. After the single and one-cycle （or one-time） radar observation DA experiments， it is found that Exp-CV6 has the greatest influence on the humidity field and the least root mean square error of specific humidity in the middle atmosphere. In addition， the influence of Exp-CV7 analysis increments is more concentrated and the gradient of analysis increments is larger， which is more conducive to retaining medium and small-scale information and has the best simulation effect on wind fields. After cyclic radar DA， Exp-CV7 is able to simulate the structure of the convective system more accurately， and the rainfall coverage and heavy precipitation center forecasted by Exp-CV7 align well with the observations. In conclusion， Exp-CV7 produces the best simulation and forecast for this study case， followed by Exp-CV6. This is mainly because the adjustment of a dynamic field by the CV7 scheme is more beneficial to the development of local convection， while the adjustment of the humidity field by the CV6 scheme is more advantageous than that by the CV5 scheme.  
        关键词：control variable;background error covariance;radar data assimilation   
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        发布时间：2023-11-01
      • LAN Jun,FU Ruixin,ZHANG Peng,XING Nan,LI Dejian,WANG Jian,XU Hongyan
        Vol. 62, Issue 3, Pages: 47-56(2023) DOI: 10.13471/j.cnki.acta.snus.2022D067
        摘要：The Xishan REE deposit is located in the western Shandong Province， which is the third largest REE deposit in China. The deposit is genetically associated with quartz syenite. In this study， we presented detailed geochemical studies on the quartz syenite to constrain its source， geodynamic setting， and metallogenetic potentials. The quartz syenite belongs to the shoshonitic series rocks and might be generated by the partial melting of a carbonate-metasomatized mantle source during the destruction of the North China craton. Compared with the quartz syenite from the Miaoniuping REE deposit in Sichuan Province， the Xishan quartz syenite is less hydrous， which might be one of the reasons that the Xishan REE deposit has a smaller mineralization scale. Considering that both the mantle sources of the Xishan and Maoniuping REE deposits were carbonate-metasomatized， combined with the carbonatite-related REE mineralization being significant in the Maoniuping REE deposit， it is worth exploring carbonatite-related mineralization in the Xishan REE deposit further.  
        关键词：Xishan REE deposit;Quartz syenite;shoshonitic;carbonate-metasomatized mantle;destruction of the North China craton   
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        发布时间：2023-11-01
      • GUO Yishu,YIN Shuyan
        Vol. 62, Issue 3, Pages: 57-67(2023) DOI: 10.13471/j.cnki.acta.snus.2022D052
        摘要：Based on the historical data in the Annals of Epidemics in China over the past 3 000 years，the time series of epidemic disasters during the Republic of China period in each county in Southwest China was extracted and sorted out， and the spatial distribution was visualized. By integrating the monthly temperature data set CRU（Climatic Research Unit） TS v.4.05， Mann-Kendall mutation test， Sen slope， and hot spot analysis， we investigated the correlation between temperature change and epidemic events. The results showed that： 1） Epidemic disasters occurred every year in Southwest China， with a total of 4170 epidemics， about 110 epidemics per year on average in the period of the Republic of China. A total of 3256 counties were affected， with an average of 86 counties per year. In the later time of the Republic of China period， the severity of epidemic disasters increased， and the frequency and affected areas simultaneously rose with some oscillations. 2） The average temperature decreased gradually from southeast to northwest in spatial distribution and increased overall temporarily with small fluctuations. 3） There was a significant positive correlation between the frequency of epidemics and temperature. Epidemics occurred frequently in summer and autumn and occasionally in winter. The cumulative years of epidemics were positively correlated with air temperature in 75.16% of the study areas， indicating that a high-temperature environment was conducive to epidemics. 4） The abrupt change and fluctuation range of temperature have significant influence on the occurrence of epidemic disaster. When the temperature fluctuation range is large， epidemic disaster occurs more.  
        关键词：epidemic disasters;spatial and temporal distribution;average temperature;the Republic of China period;the southwest region   
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        发布时间：2023-11-01
      • MA Jianjun,CHEN Jianying,CHEN Wanxiang,XUE Haien,XU Zhengyang
        Vol. 62, Issue 3, Pages: 68-78(2023) DOI: 10.13471/j.cnki.acta.snus.2022B031
        摘要：Dynamic responses of RPC-filled steel tubular （RPC-FST） columns under uncertain blast loading are investigated， and the failure mechanisms are further analyzed. The blast loads， induced by cylindrical charge with different orientations， length-to-diameter ratios and detonation positions， are simulated using LS-DYNA software. The distributions of shock waves caused by explosive charge with scaled distance ranging from 0.4 m/kg1/3 to 0.8 m/kg1/3 is obtained， and normal distribution tests are carried out based on the numerical results. The polynomial fitting formulas for average and maximum values of peak reflected overpressure are achieved， and the uncertain blast models are finally presented. The dynamic responses and failure mechanisms of the RPC-FST column are analyzed systematically by simplifying the statistical loads into equivalent loads. Results show that the reflected overpressure follows normal distribution. The bending deformations can be observed in the middle span of the RPC-FST column， while shear deformations are found near the support. More severe damage can be observed in the RPC-FST column subjected to maximum blast loading compared to the average value， and the structure tends to shear failure.  
        关键词：RPC-filled steel tubular column;uncertain blast loading;lognormal distribution;dynamic response;failure mechanism   
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        发布时间：2023-11-01
      • WANG Mingkang,LI Jie,LU Hongmei,CAI Yongbin
        Vol. 62, Issue 3, Pages: 79-88(2023) DOI: 10.13471/j.cnki.acta.snus.2022B066
        摘要：Four different cooling measures were proposed to aim at the excessive indoor temperature problem of passive solar house in summer. A passive solar house in the Shihezi area of Xinjiang was taken as the study object. The method of numerical simulation combined with an experimental test was used to compare and analyze the cooling effect of the four cooling measures. The results show that： comparing the numerical simulation results with the experimental results， the average value of the indoor temperature deviation under each cooling measure is 2 ℃， but the temperature change trend is consistent and has good conformity， which confirms the feasibility of the numerical simulation. Compared with the passive solar house in the natural state， thermal comfort requirements can be met 46%， 50% and 50% of the time， respectively. Using shading， closing the south window combined with shading or thermal pressure ventilation， thermal pressure ventilation combined with shading achieves thermal comfort requirements 92% of the time.  
        关键词：passive solar houses;cooling;numerical simulation;ventilation;shading   
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        发布时间：2023-11-01
      • ZHANG Xuefei,ZHAO Junke,HAO Suqi,DING Qing,YU Shihui,MOHAMMAD Imran shair,WANG Jun,HU Haiyan
        Vol. 62, Issue 3, Pages: 89-99(2023) DOI: 10.13471/j.cnki.acta.snus.2022E027
        摘要：Dai antidotes are the most distinctive medicine and treatment in traditional Dai medicine. Bin Hao (Clerodendrum chinense var. simplex), Dai Bai Jie (Marsdenia tenacissima) and Zhu Ye Lan (Arundina graminifolia) are three Dai antidotes widely used for their "detoxifying effects", and their use is rooted in a theoretical system significantly different and much less understood than Western or traditional Chinese medicines. Here, we successively extracted the three Dai antidotes using petroleum ether, ethyl acetate, n-butanol, or water, and then prepared their decoctions. The content of total flavonoids in three Dai antidotes ranged from 22.41 to 586.39 mg/g, which is higher than the content of total polyphenols (2.76 to 28.66 mg/g). The various extracts were found to scavenge radicals of DPPH, ·OH and ABTS. They scavenged ABTS radicals much more efficiently than other radicals (IC50 > 380 μg/mL). They weakly inhibited the growth of E. coli, P. aeruginosa and S. aureus. Notably, even at low concentration 60 μg/mL, the extracts can significantly down-regulate the production of NO, TNF-α, IL-1β, and IL-6 by macrophages stimulated with LPS. In conclusion, our results provide the first mechanistic insights into the detoxifying effects of three Dai antidotes, providing a foundation for their optimization and for future research to strengthen Dai medicine through modern scientific practices.  
        关键词：Dai antidote;Clerodendrum chinense var. simplex;Marsdenia tenacissima;Arundina graminifolia;detoxification   
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        发布时间：2023-11-01
      • WANG Yuxia,ZOU Xiuzai,LI Chunyu,ZHANG Ke,LIANG Zishan,WANG Hongbin,DUAN Lixin,JIN Honglei,SHEN Qi
        Vol. 62, Issue 3, Pages: 100-108(2023) DOI: 10.13471/j.cnki.acta.snus.2022E017
        摘要：Andrographis paniculata（Burm.f.）Nees is a traditional medicinal material and is widely used in China. In order to evaluate the genetic diversity of Andrographis paniculata germplasm， this study collected germplasm materials from two main producing areas in Zhanjiang， Guangdong and Guigang， Guangxi， and then investigated their yield traits and main medicinal components. The results showed that the yield characters and medicinal components of Andrographis paniculata from the same source showed great variation. Among the yield traits， the maximum variation of biomass per plant was 100~624 g， and the remaining coefficients of variation were leaf weight， leaf area， number of primary branches， growth period， and plant height in descending order. Among the properties of medicinal components， andrographolide has the largest range of 1.538 5~6.594 4 mg/g， and the rest are neoandrographolide， 14-deoxyandrographolide， and deoxyandrographolide. The analysis of the tested materials found that the germplasm was poor in purity and degree， and had significant genetic diversity， which provided a rich material basis for material selection and genetic breeding. In addition， the correlation analysis showed that the main yield traits of Andrographis paniculata were significantly negatively correlated with the content of the main medicinal components. During material selection， attention should be paid to the balance between yield traits and medicinal components. Finally， further cluster analysis was carried out according to yield traits and medicinal components to screen important materials. The results of this study provide a breeding research material basis for the protection of germplasm resources of Andrographis paniculata and the selection of elite varieties.  
        关键词：Andrographis paniculata（Burm.f.）Nees;genetic diversity;yield traits;medicinal components;correlation analysis;cluster analysis   
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        发布时间：2023-11-01
      • BAO Wenjie,LIU Shengjie
        Vol. 62, Issue 3, Pages: 109-115(2023) DOI: 10.13471/j.cnki.acta.snus.2022E031
        摘要：Biological control of pests is an important ecosystem service. This research aimed to explore the dynamic change of spider community in tea plantation ecosystem， and compare the predation efficiency of spiders with different species identities and foraging strategies to the green leafhopper pest， Empoasca vitis Gothe （Homoptera： Cicadellidae）. This study combined field survey with feeding experiment in the lab， investigated the dynamic change of spider community in Apr.， Jun.， Aug. and Nov. in Dajian Mountain Tea Plantation in Pu’er City， Yunnan Province from 2012 to 2013. Furthermore， eight common spider species were collected from tea plantation and divided into sit-and-wait spider （SW spider） and actively hunting spider （AH spider） according to their predation strategies. The daily leafhopper consumption of each individual spider was measured in the microecosystem simulated to tea plantation. The results showed that the species number and abundance of spiders in Dajian Mountain Tea Plantation increased significantly in Jun. and Nov.， and the sit-and-wait spiders were the dominant ones； the predation efficiency of different spider species on the green leafhopper was significantly different and the daily leafhopper consumption of AH spiders was significant higher than that of SW spiders. In conclusion， the changes of spider community in the tea plantation are related to the population dynamics of the green leafhopper， and the species identity and foraging strategy of spider will significantly affect the predation efficiency to the green leafhopper. Therefore， an in-depth understanding of the characteristics of predatory natural enemies will help to better predict the effect of biological control of pests in tea plantation ecosystem.  
        关键词：foraging strategy;biological control;Empoasca vitis Gothe;actively hunting spider;sit-and-wait spider   
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        发布时间：2023-11-01
      • WANG Kaimin,YANG Liangzhu,LI Lifeng,MA Yulu,FAN Baomin,SUN Weiqing
        Vol. 62, Issue 3, Pages: 116-124(2023) DOI: 10.13471/j.cnki.acta.snus.2022C017
        摘要：A two-dimensional coordination polymer CP 1 with a double-intercalated structure was synthesized by zwitterionic organic ligand 4-carboxy-1-（3-carboxybenzyl）pyridine-1-onium chloride， 1，2-bis（pyridin-4-yl）ethene， NaOH and Zn2+ under solvothermal conditions. The structure of the CP 1 was characterized by the single-crystal X-ray structure， powder diffraction spectrum and thermal stability analysis. Its application potential in the field of fluorescence sensing materials was investigated by the solid fluorescence and liquid fluorescence analysis. Results show that CP 1 can identify aristolochic acid A by fluorescence quenching. In the low concentration range of 5.0～35.0 μmol/L， the quenching efficiency is linearly related to the concentration of aristolochic acid A， the detection limit was 0.022 μmol/L. The interaction time of CP 1 and aristolochic acid A is 60 s， and CP 1 can keep the structure stable in five cycles. The prepared CP 1 has good fluorescence properties， and has sensitive， rapid and recyclable fluorescence sensing performance for aristolochic acid A in ethanol， and it can be used as a fluorescence sensor to detect low concentration of aristolochic acid A.  
        关键词：coordination polymer;zwitterionic ligand;aristolochic acid A;fluorescent sensing material;fluorescence detection   
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        发布时间：2023-11-01
      • PAN Ligui,YIN Jiaqi,XU Chunguang
        Vol. 62, Issue 3, Pages: 125-136(2023) DOI: 10.13471/j.cnki.acta.snus.2022B022
        摘要：We proposed a new method for the relative positioning problem in UAV clusters using carrier phase as the observation data， which includes three features. First， an antenna configuration with a triangular geometric relationship is designed to build a relative observation model between UAVs. Second， the extended Kalman filter algorithm is utilized to calculate the UAV position and velocity state parameters. The UAV attitude angle and its angular rate parameters are further solved. Third， to study the cooperative positioning performance of UAV clusters， one master UAV is extended to three master UAVs， thus obtaining the effect of the number and layout of master UAVs on UAV positioning accuracy. The simulation results show that the inter-aircraft relative observation model can effectively estimate the UAV position and velocity state parameters. The further solved UAV attitude angle and its angular rate parameters can meet the accuracy requirements， which verifies the feasibility of the method. In addition， with an increased number of master UAVs and a decentralized layout， the method can significantly improve the accuracy of the UAV's state estimation.  
        关键词：UAV cluster;relative positioning;carrier phase;extended Kalman filter   
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        发布时间：2023-11-01
      • CHEN Wei,WEI Xuemei,FENG Zhaoyong,LIU Chengxia
        Vol. 62, Issue 3, Pages: 137-148(2023) DOI: 10.13471/j.cnki.acta.snus.2022A040
        摘要：A mathematical model of checkpoint inhibitor targeted therapy for human melanoma is investigated. The model consists of twelve coupled reaction-diffusion equations, which includes free boundary conditions and discontinuous terms. By transforming the free boundary problem into the fixed boundary problem, using the Lp theory of the parabolic equation and the Schauder fixed point theorem, and combining with the method of function approximation, the existence of the global weak solution of the mathematical model is obtained.  
        关键词：melanoma;reaction-diffusion equations;weak solution;existence   
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      • KANG Yujiao,ZHANG Tailei,MA Yiting,LIU Junli
        Vol. 62, Issue 3, Pages: 149-160(2023) DOI: 10.13471/j.cnki.acta.snus.2022A008
        摘要：According to the transmission mechanism of hepatitis C， we establish an SEICR hepatitis C model with infectious latency and relapse effect， and give the basic reproductive number of the model. It is proved that the disease-free equilibrium is globally asymptotically stable when ℛ0<1；the disease-free equilibrium is unstable and the endemic equilibrium is globally asymptotically stable when ℛ0>1. Choosing the case data of hepatitis C patients of Shaanxi Province， we use the model to simulate the epidemic trend of hepatitis C in the next a few years. Finally， the sensitivity analysis of parameters shows that the number of hepatitis C cases will continue to increase in recent years. Improving public awareness of hepatitis C detection and strengthening immunity can improve the recovery rate of hepatitis C patients and reduce the proportion of disease relapse， so as to control the further spread of hepatitis C.  
        关键词：SEICR model;hepatitis C;stability;numerical simulation   
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        发布时间：2023-11-01
      • SHI Jincheng
        Vol. 62, Issue 3, Pages: 161-168(2023) DOI: 10.13471/j.cnki.acta.snus.2021A004
        摘要：The continuous dependence of Brinkman equations with Soret effect on a three-dimensional bounded convex domain is considered. By using differential inequality， the correlation estimates of the solution is obtained， especially the fourth-order norm estimation of salt concentration is derived. Finally， using the energy method and the prior estimation， the continuous dependence of the solution of the equations on Brinkman coefficient λ is established.  
        关键词：Brinkman equations;continuous dependence;Brinkman coefficient;Soret coefficient   
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        发布时间：2023-11-01
      • HU Xiaoyan,SANG Bo
        Vol. 62, Issue 3, Pages: 169-174(2023) DOI: 10.13471/j.cnki.acta.snus.2021A027
        摘要：Based on the theory of linear space， a family of cubic jerk systems with Z2 symmetry is constructed， which has a zero-Hopf equilibrium at the origin when ε=0， i.e. an isolated equilibrium with a zero eigenvalue and a pair of purely imaginary eigenvalues. Using this result， the number of small amplitude limit cycles is studied for the perturbed system. By the help of averaging theory of fourth order， it is proved that at most 5 small amplitude limit cycles can bifurcate from the equilibrium and the bound can be reached， which improves a previous result.  
        关键词：zero-Hopf equilibrium;averaging theory;limit cycle   
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        发布时间：2023-11-01
      • ZHU Lina,LI Jingwen,SUN Shuai
        Vol. 62, Issue 3, Pages: 175-183(2023) DOI: 10.13471/j.cnki.acta.snus.2021A032
        摘要：The distance coloring problem of graph is a graph model for frequency allocation problem. The so-called frequency allocation problem refers to that different radio stations in a certain area need to use radio waves to send signals. In order to avoid interference， stations in close proximity need to use different channels， and when stations are particularly close， they need to be separated by at least two channels. L2,1-edge coloring means that the chromatic number difference of two edges with distance 1 is greater than or equal to 2， and the chromatic number of two edges with distance greater than 1 is different. In this paper， an L2,1-edge coloring algorithm is designed for random graphs. According to the experimental results， it is shown that the L2,1-edge coloring problem of random graphs in finite points can be solved through the algorithm. Meanwhile， the coloring properties of three kinds of unicyclic graphs are found here， and we define C3↑Pn↑Sm，Cn↓Sm and Cn↑Sm to characterize these three kinds of unicyclic graphs respectively. The related theorems and proofs are given as well.  
        关键词：L2,1-edge coloring;chromatic number;unicyclic graph;algorithm   
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