最新刊期
卷 60 ， 期 4 ， 2021
- 摘要：Ecological control of exotic invasive plants refers to controlling exotic plant invasions through ecological approaches， such as manipulating species composition of native plant and microbial communities and modifying environmental conditions. The major challenge in plant invasion control that has been troubling scientists across the world is the prevention of recurring outbreaks of plant invasion， which often happened following traditional physical， chemical and biological controlling approaches. In this paper， we reviewed the current knowledge on ecological control of exotic invasive plants by referring to the latest research advances across the world and the experiences in the ecological-control practices by our research team. Following four major aspects were highlighted： ① control by native plants， ② control by plant-microbe feedback， ③ control by allelopathy， and ④control by modification of environmental conditions. The review aimed to help understanding of the basic theories and practical options for ecological control of exotic plant invasion.关键词：exotic invasive plants;ecological control;basic theories;guidance for practice
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发布时间：2023-11-01
Invited review
- 摘要：This study conducted experiments on the effects of different soil water content and soil surface types on egg-laying and larval development of Forcipomyia taiwana （Shiraki）. The relationship between soil water content of field grassland and the total number of durian bites of F. taiwana was analyzed. The effects of soil water content on the oviposition， hatching rate， larval survival rate and pupation rate of F. taiwana were studied under seven soil environments， including 0%-10%， 10%-20%， 20%-30%， 30%-40%， 40%-50%， 50%-60% and 60%-70%. The experiments were carried out under （25±2） ℃， （70±10）% relative humidity and 12L∶12 days photoperiod. The differences of spawning quantity of F. taiwana on four types of soil surface， bare soil， gravel， broken pine bark and fertilized soil， were studied. The results showed that soil water content and types of soil surface had significant effects on the oviposition of F. taiwana. F. taiwana laid the highest number of eggs on bare soil with water of 30%-40%. The amount of spawning was highest on bare soil surface. Gravel， broken pine bark and fertilized soil were negative to egg-laying of females. Soil water content had no significant effect on larval development and pupation.关键词：Forcipomyia taiwana（Shiraki）;soil moisture content;soil surface types;oviposition preferences
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发布时间：2023-11-01 - 摘要：The study aims to investigate the effect of different dosages of Suaeda rigida polysaccharides on the contractile activity of the isolated rabbit duodenum and explore its mechanism. The contractile activity of the isolated duodenum was recorded by Medlab biological signal acquisition and processing system before and after administration， and the effects of Suaeda rigida polysaccharides-treated groups of the low， medium， and high doses on the contractile frequency and amplitude of the intestines were observed. Acetylcholine （ACh） and CaCl2 were selected respectively to be co-incubated with the high dose of Suaeda rigida polysaccharides to observe the effects on the duodenal contraction. The effects of different doses of Suaeda rigida polysaccharides on the contents of Leu enkephalin （Leu-enk）， met enkephalin （Met-enk） and the activity of tyrosine hydroxylase （TH） in the isolated rabbit duodenum were detected by enzyme-linked immunosorbent assay （ELISA）. The results showed that the three dose groups of Suaeda rigida polysaccharides had inhibitory effects on the contractile frequency and amplitude of the isolated duodenum in rabbits compared with those before administration. Among them， the inhibition of the low dose group was not significant （P>0.05）， the medium dose group was significant （P<0.05）， and the high dose group was very significant （P<0.01）， showing a dose-dependent effect. The high dose of Suaeda rigida polysaccharides could significantly （P<0.01） inhibit the promotion effects of ACh and CaCl2 on the frequency and amplitude of intestinal contraction， and the inhibitory effects were similar to those of atropine sulfate and verapamil hydrochloride， respectively. The results of ELISA showed that compared with the control group， the contents of Leu-enk and Met-enk in the isolated rabbits duodenum in the three groups of Suaeda rigida polysaccharides were decreased in varying degrees， and the activity of TH was increased in varying degrees. These results indicated that Suaeda rigida polysaccharides can inhibit the contraction of the isolated rabbit duodenum. The mechanism may be that it can inhibit the signal transduction pathways of AC-cAMP-PKA and PLC-IP3-Ca2+ and Ca2+ signaling systems mediated by G protein-coupled M receptor through the intestinal myenteric plexus； it may inhibit the GTP-cAMP-（PKK or PKC） signaling pathways and Ca2+ signaling systems mediated by G protein-coupled δ receptor by inhibiting the release of Leu-enk and Met-enk from the motor neurons of the myenteric plexus； it may also cause the increase of NE by promoting the release of TH from the motor neurons of the myenteric plexus and reactivate the AC-cAMP- PKA signaling pathway mediated by the G protein-coupled β receptor.关键词：Suaeda rigida polysaccharides;duodenal smooth muscle;myenteric plexus;neurotransmitter
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发布时间：2023-11-01
- 摘要：This study was conducted to investigate the effects of starvation stress on the activities of six immune enzymes in the intestine， blood， hepatopancreas and muscle of Harpiosquilla harpax. The experimental animals were starved for 1， 6， 11 and 21 days， then samples were collected and activities of immune enzyme were analyzed， respectively. The results showed that， effect on the activities of immune enzymes was significantly by starveling time （P < 0.05）. The immune enzyme activity of the animal was induced when mild starvation and inhibited under severe stress. With the prolongation of starveling time， it was shown that： 1） the activities of various immune enzymes of CAT， ACP， AKP， T-SOD， GSH-PX and POD in the intestine all showed a trend of "increase first， then decrease"； 2） in blood， except CAT， showed a trend of "first decrease then increase"， the others increased first and then decreased； 3） in hepatopancreas， the activity of CAT decreased gradually， ACP， AKP， T-SOD and POD showed a trend of "increase first and then decrease"， while GSH-Px showed a trend of "decrease first and then increase"； 4） in muscle tissue， except that AKP slightly decreased， the other immune enzyme activities showed a trend of "increase first and then decrease".关键词：Harpiosquilla harpax;starvation stress;immune enzyme;antioxidant
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发布时间：2023-11-01 - 摘要：To understand the effects of low temperature stress on lysosomes or another organella in the mesophyll cell of Osmanthus fragrants ‘Wandian Jin’， we chose three years old O. fragrans ‘Wandian Jin’ as the test material. The intelligent artificial climate chamber was applied to simulate the natural cooling process for O. fragrans. After sampling and making slices， the mesophyll cell of O. fragrans was used for investigation with the transmission electron microscope. The results showed that the chloroplast and mitochondrion's structures did not display abnormal， however， the number of lysosomes decreased. Under the treatment of the low temperature at 5 ℃， some chloroplasts occurred a degree of swelling compared with that at the normal temperature； the number of osmiophilic granules and mitochondrions was increased； primary lysosome was found to coexist with secondary lysosome and their numbers grew. At low temperatures 0 ℃， chloroplast was more and more expand， some chloroplasts showed a spheroidicity shape； the amount of osmiophilic granule was significant； starch grain swelled and enlarged； the number of mitochondrion was increased； the structure of secondary lysosome was complicated and varying in size. At low temperatures -5 ℃， chloroplast swelled more strongerly than in the early， parts of the chloroplast were dissociated in the center of cells； the number of the mitochondrion， the primary lysosome and secondary lysosome was increased， and the shapes of lysosome varied. In addition， the mesophyll cells showed to ice intracellularly ice and freeze intercellularly.关键词：Osmanthus fragrans;low temperature stress;lysosome;ultrastructure
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发布时间：2023-11-01 - 摘要：The study aimed to explore the mechanism of action of Bufei Huoxue Capsule （BFHXC） for treatment of pneumonia recovery through network pharmacology. The constituents of BFHXC were collected by preliminary studies. The targets of constituents were collected by TCMSP and Toxicogenomics Database （CTD） as well as by prediction of SwissTargetPrediction based on structural similarity. Protein-protein interaction （PPI） data was constructed by using String website for screening key targets. The herb-active ingredient-key target network was constructed by using Cytoscape software，followed by topology analysis. The DAVID database was used to perform GO enrichment analysis and KEGG pathway analysis on the key targets for predicting the mechanism of action of BFHXC. A total of 1 102 targets were collected for BFHXC， and 215 key targets were screened， such as AKT1， MAPK3， VEGFA， CASP3， EGFR and so on. The results of pathway enrichment indicated that TNF signaling pathway， T cell receptor signaling pathway， Rap1 signaling pathway， PI3K/Akt signaling pathway， HIF-1 signaling pathway and FoxO signaling pathway were the key pathways， which were involved in the treatment of pneumonia recovery. BFHXC may exhibit therapeutic effects on pneumonia recovery probably through inhibiting inflammation and relieving pulmonary fibrosis based on multi-target and multi-pathway.关键词：Bufei Huoxue Capsule;pneumonia recovery;network pharmacology
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发布时间：2023-11-01 - 摘要：The chiral transition of amphoteric α-alanine divalent zinc （α-Ala·Zn2+） complexes was studied by using the M06 and MN15 method based on SMD model method of self-consistent reaction field theory in Water/Liquid Phase. Three reaction pathways a， b and c were investigated. In pathway a， α-H is transferred using carbonyl O atom as a bridge. α-H is transferred with Zn atom and amino N atom as bridges in pathway b and c， respectively. Potential energy surface studies indicate that the chiral transition reaction in pathway c has the most advantage. The free energy barrier which comes from the transition state of α-H transfers from α-C to amino N atom is 164.9 kJ·mol－1. The pathway a of the chiral transition reaction is the second dominant pathway. The free energy barrier which comes from the transition state of α-H transfers from α-C to Carbonyl O atom is 168.9 kJ·mol－1. The pathway b of the chiral transition reaction is the disadvantaged pathway. The free energy barrier which comes from the transition state of α-H transfers from α-C to Zn atom is 194.2 kJ·mol－1. The results show that α-Ala·Zn2+ can maintain its chiral characteristics well in Water/Liquid Phase.关键词：alanine;zinc ions;chiral transition;density functional theory;self-consistent reaction field theory;transition state;energy barrier
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发布时间：2023-11-01 - 摘要：Based on the uncertainty in the process of land development and the assumption of irreversibility of land conversion， the decision-making problem of land development is ransformed into an optimal stochastic control model under the framework of real option theory， while allowing for a feedback between conversion decisions and the conservation benefits. A new variable ‘ecological value per unit area’ is introduced to establish corresponding Bellman equation using the principle of dynamic programming. The appropriate boundary conditions of the equations derived； and the finite difference method is used to solve the key equation numerically. The dynamic optimal path of land development and ecological protection is discussed numerically based on the relevant data of the Three Rivers Source Region. The results show that： （1） there is a non-linear relationship between the land option value and the proportion of the ecological land area， which leads to an optimal conversion state in the process of land development； （2） the increase of agricultural benefits will accelerate the process of land conversion， and the area of agricultural production land will increase in the optimal conversion state of land； （3） the increasing elasticity of ecosystem protection benefits will slow down the land conversion process； （4） the increasing uncertainty of ecological value will accelerate the land conversion process.关键词：land development decisions;ecological protection;Three Rivers Source Region;real option model;finite difference method
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发布时间：2023-11-01 - 摘要：The diverse sources of magnetic minerals in lake sediments usually cause uncertainties in the reconstruction of the paleoenvironment using the magnetic parameters. Clarifying the sources of magnetic minerals and the possible changes in magnetic parameters for the source and the sink area of the sediment respectively， is the basis for a more accurate interpretation of the magnetic parameters representing the environmental significance. In this paper， the sediments of a closed karst lake in Wuxuan County， Guangxi Province was selected to discuss this transform. Surface soil samples from the catchment area and top sediments samples in the lake were taken respectively for performing the detailed rock magnetic measurements， then discussing the variations of the magnetic minerals in concentration， assemblage and domain state. The results show that the magnetic minerals of lake surface sediments and catchment soil samples dominated mainly by the magnetite， however， the lake sediments are mainly composed of SD magnetite while the soil samples characterized mainly by the PSD magnetite， containing higher percentage of superparamagnetic minerals and lepidocrocite. The difference in magnetic properties between the two groups of samples indicates the post-depositional effects in the surface sediments of the lake， which resulted in a degree of reduction and dissolution of the detrital magnetic minerals and the formation of biogenic magnetic minerals. Therefore， the magnetic susceptibility（χ）， frequency dependent susceptibility（χfd）， saturation magnetization （Ms） and related magnetic parameters of the sediment may remain some uncertainties for reconstructing the environmental background during deposition. The anhysteretic remanent magnetisation （ARM） and saturation isothermal remanence （Mrs or SIRM） are less affected by post-depositional alternation and may be good substitute indicators for recovering environmental information when sediments were formed.关键词：closed karst lake;catchment surface soils;lake surface sediments;rock magnetism;magnetic minerals
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发布时间：2023-11-01 - 摘要：The aeromagnetic anomalies in the Pearl River Delta region show noticeable zones， which present a background of EW-direction zones and also exist aeromagnetic fields of NE and NW directions. By processing， analyzing and interpreting the aeromagnetic data， it is confirmed that three sets of faults， i.e.， the EW-， NW- and NE-direction faults， constitute the framework of deep faulting system of the Pearl River Delta region. The EW-trending faults are major faults and most of them reach the depth over 30 km. The NW-trending ones are well-developed in the delta， but their depths are merely around 10 km. The NE-trending faults are also shallow； the depths of some NE faults， which are considered with a depth over 30 km previously， are about 10 km and definitely less than 20 km according to our interpretation. The three sets of faults are intersected each other； the EW and NW faults are more active than the NE ones， and their activity ages are newer as well. These results are agreement with those obtained from gravity data of the area， but different largely from the traditional cognizance of the deep fault structure of the Pearl River Delta region. A new concept of neotectonic stage of deep faults is proposed to explain these features.关键词：the Pearl River Delta region;aeromagnetic anomalies;deep faults;nectectonic stage
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发布时间：2023-11-01 - 摘要：During the submarine optical cable route survey， the laying cable is hard to be detected by sonar detection as side-scan sonar or shallow stratum profile instrument， because of its slender shape and buried depth，this paper introduces the structure and magnetic characteristics of the submarine optical cable， and emphatically analyzes the magnetic anomaly forward curve of the submarine optical cable with remote power supply. We detected actual the optical cable that is similar to the forward model. It is verified that the submarine optical cable magnetic anomaly is mainly generated by the current， and is related to the current intensity and the depth of burial. The position of the optical cable is at the geometric center of the magnetic anomaly curve. According to the magnetic anomaly forward curve feature of laying cable， the magnetic detection method can be used with the underwater positioning system to pinpoint the optical cable. Taking China shallow water section of Bay to Bay Express cable （BtoBE） as an example. We discusses the surveying line layout， equipments， data processing， profile-plan drawing. This paper has a reference meaning for explaining the magnetic anomaly of submarine optical cables and implementing magnetic detection in similar projects.关键词：submarine optical cable;magnetic exploration;forward curve
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发布时间：2023-11-01 - 摘要：Vehicle re-identification （Re-ID） aims to identify a target vehicle from multiple non-overlapping cameras. Vehicle Re-ID is a challenging work because it's hard to distinguish vehicles of the same model with similar appearance. Since the differences between these vehicles are concentrated in some small local regions， a detail-aware discriminative feature learning model is proposed in this paper， based on the assumption that features of network's middle layer is helpful in extracting discriminative feature representation of local regions. In the proposed model， a guided vehicle local feature extraction process is designed， and the final feature representation of vehicle consist of the extracted local feature and the global feature extracted by the backbone network. Extensive experiments over benchmark datasets VehicleID and VeRi have shown that the proposed methods could achieve superior performance than state-of-the-art methods.关键词：vehicle re-identification;neural network;local feature extraction;discriminative feature learning
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发布时间：2023-11-01 - 摘要：The influence of interfacial elastic modulus of reinforced concrete beams on crack propagation has been simulated in this paper. Non-uniform distribution of Weibull statistical theory has been adopted when setting concrete model. The failure process diagrams of crack initiation， propagation and penetration， peak load curve and acoustic emission （AE） curve have been obtained. The results show that variation of interfacial modulus has a significant influence on the crack propagation pattern， with increase of the interface elastic modulus of specimens， failure pattern of the specimen gradually changes from bending tensile failure dominated by bending cracks to shear failure dominated by oblique cracks. Both peak load of tested beams and accumulative AE events increase first and then decrease with the increase of interfacial modulus. There are three obvious “jump points” in the cumulative AE curve and four extreme points in the histogram of AE events of each specimen， respectively， which correspond to different failure stages， respectively.关键词：three dimension dynamic;failure process;interfacial modulus;acoustic emission
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发布时间：2023-11-01 - 摘要：The traditional cable forces adjustment method fails to consider the coupling relationship between the saddle angle and the anchor span cable forces effectively， which can be dangerous to some extent. In order to adjust the anchor span cable forces and the saddle angle of the suspension bridge in security and high speed， based on the rotation stiffness of saddle， the effects of temperature and sag deviation of side span on the saddle angle are studied. Combined with the practice of a three-tower suspension bridge， a simplified method of cable forces adjustment considering the rotation effect of the saddle is proposed. The results of practice show that： temperature change is the main reason for the deflection of the saddle. The relationship among the variation of temperature and the deviation of side span sag and the angle of splay saddle deflection is derived. Its correctness and calculation accuracy have been verified in the practice.The simplified method of cable forces adjustment can significantly reduce the adjustment times， thus a high cable adjustment accuracy is achieved， and can effectively prevent the cable strand from slipping， which has the advantages of simple operation， time saving and high safety.关键词：rotating stiffness of saddle;temperature change;sag deviation of side span;cable forces adjustment;saddle angle
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发布时间：2023-11-01 - 摘要：An new improved variable-fidelity surrogate model（ICokriging model） was proposed. Based on the CoKriging model， we extended two different samples of the high-precision and low-precision of the CoKriging model to three different samples with high-precision， medium-precision and low-precision in the ICoKriging model.This new proposed model has higher accuracy and it is easier to find global optimization compared with the Kriging model and the CoKriging model，which was verified by numerical examples and a supersonic drag reduction problem.关键词：CoKriging model;ICoKriging model;drag reduction
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发布时间：2023-11-01 - 摘要：Several unique common fixed point theorems for four non-continuous and weakly compatible self-mappings satisfying
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发布时间：2023-11-01 - 摘要：Medical-image-based human bodypart recognition，which aims to accurately locate the bodypart of a specific medical image，is an essential preprocessing step for many medical image analysis tasks.Currently，computed tomography （CT） is one of the most available medical imaging techniques in clinic.Many CT-based medical image analysis algorithms （such as lesion detection，organ segmentation，etc.） need to first identify the bodypart information contained in the CT image to obtain prior knowledge，so as to ensure the speed and robustness of the algorithms.However，CT images are reconstructed from CT raw data，which is also known as CT sinogram.And the image reconstruction process may cause information loss.Therefore，compared with CT images，CT sinogram may contain more effective information suitable for bodypart recognition tasks.However，there are still relatively few researches on bodypart recognition based on CT sinogram.Therefore，the deep learning based convolutional neural network （CNN） technique is used to train on CT sinogram and its usability in bodypart recognition tasks is verified.A public dataset （i.e.，DeepLesion） and three clinical datasets from well-known medical institutions are adopted to verify the performance of our proposed method.Specifically，the Radon transform is used to perform data simulation on CT images to obtain CT sinogram，which is served as input to train a CNN-based classifier （Sino-Net） to recognize the five most common bodyparts （i.e.，head，neck，chest，upper abdomen and pelvis）.The experimental results show that the use of CT sinogram for bodypart recognition can achieve similar performance to the use of CT images，and sometimes even better than the results based on CT images.关键词：CT sinogram;convolutional neural network;bodypart recognition;multi-class
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发布时间：2023-11-01 -
Singularity and decay estimate of solutions of a system of semi-linear degenerate elliptic equations
摘要：Some singularity and decay estimates of solutions for a degenerate semi-linear elliptic equation system are established based on re-scaling arguments combined with a doubling property. As an application， a priori bound of solutions of a boundary value problem to a degenerate semi-linear elliptic equation system is derived.关键词：re-scaling;singularity and decay;a priori bound- 5
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发布时间：2023-11-01 - 摘要：An internal acoustic inverse scattering problem with a Neumann boundary condition is studied by using the decomposition method. First， it is proved that the position and shape of a scatterer can be uniquely determined by the measurement data of the point source inside the cavity with the Neumann boundary condition. Then， the boundary of the unknown scatter and its shape is reconstructed by using the idea of the decomposition method. Finally， two numerical examples are given to verify the feasibility and effectiveness of the method.关键词：interior inverse scattering problem;Neumann boundary condition;the decomposition method
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发布时间：2023-11-01 - 摘要：In the field of risk management， VaR has been highly valued and the measurement of VaR by GARCH model is an important research. In practical application， it is necessary to specify the conditional distribution form when using traditional parameter GARCH model for modeling. However， the model will become invalid if the distribution is specified incorrectly. Therefore， under the standard GARCH（1，1） model， the residual error is corrected in combination with the cumulative empirical distribution function， so as to avoid the model risk caused by the pre-specified error of the traditional parameter distribution. In the empirical research， it is found that the proposed method is greatly improved compared with the standard GARCH（1，1） model based on specified parameter distribution in the measurement of VaR， and its failure frequency and relative error are significantly reduced.关键词：VaR;standard GARCH model;the cumulative empirical distribution function;the tail distribution
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发布时间：2023-11-01
Research articles
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