Reservoirs are an important water source in many densely populated areas in southwest China.Phytoplankton play an essential role in maintaining the structure and function of reservoir ecosystems.Understanding the succ...Reservoirs are an important water source in many densely populated areas in southwest China.Phytoplankton play an essential role in maintaining the structure and function of reservoir ecosystems.Understanding the succession in phytoplankton communities and the factors driving it are essential for eff ective water quality management in drinking water reservoirs.In this study,water samples were collected monthly at the surface layers from March 2016 to December 2019 in Hongfeng Reservoir,southwest China.The relationship between functional group succession was analyzed based on nonmetric multidimensional scaling analysis(NMDS),redundancy analysis(RDA),succession rate,and other analysis methods.The results showed distinct shifts in the community structure of phytoplankton functional groups within study period.The Cyclotella sp.was dominant in 2016 and 2017,and Pseudanabaena limnetica was the dominant group in 2018 and 2019.It appears that the phytoplankton composition and biomass are closely related to the water temperature and nutrient status in this reservoir.The results clearly showed that the permanganate index(COD_(Mn))was the key factor of dramatic phytoplankton functional group succession,and the change in succession rates was closely caused by total nitrogen concentration(TN).Therefore,the succession pattern and key factors of Hongfeng Reservoir revealed in this study were important guidance for the management of drinking water reservoirs in southwest China.A reasonable limit on exogenous nutrient input should be a priority,especially in high water temperature period.展开更多
[Objectives]The purpose was to investigate the function and mechanism of exsA gene in type III secretion system of Vibrio alginolyticus.[Methods]The full length of exsA was cloned using molecular biology techniques to...[Objectives]The purpose was to investigate the function and mechanism of exsA gene in type III secretion system of Vibrio alginolyticus.[Methods]The full length of exsA was cloned using molecular biology techniques to analyze its biological information.Fluorescence quantitative PCR technology was used to analyze the expression of exsA after different media stress.[Results]The exsA gene contains an open reading frame(ORF)of 861 bp,encoding 286 amino acids.The physico-chemical analysis shows that the molecular structural formula is C1442H2267N393O441S12,the theoretical molecular weight is 32.549 kD,the theoretical pI value is 6.0,and the protein is non-hydrophilic and unstable.The gene does not contain a transmembrane region,and there is no obvious signal peptide.The prediction result of protein subcellular localization shows that the protein is inside the cell.The deduced amino acid sequence and constructed phylogenetic tree show that V.alginolyticus has a close relationship with Vibrio antiquarius.The qPCR results show that the expression level of exsA in different media is different,highest in TSB medium containing bile salts,followed by DMEM medium,and lowest in ordinary TSB medium.[Conclusions]The gene sequence,molecular structure and isoelectric point of exsA,as well as its expression in three different media were obtained.展开更多
Apoptosis and viability of PC12 cells following 1-methyl-4-phenylpyridinium ion （MPP＋）-induced injury were monitored by flow cytometry, following Annexin V-propidium iodide double labeling, and 3-（4,5-Dimethylthia...Apoptosis and viability of PC12 cells following 1-methyl-4-phenylpyridinium ion （MPP＋）-induced injury were monitored by flow cytometry, following Annexin V-propidium iodide double labeling, and 3-（4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay, respectively. The release of lactate dehydrogenase, superoxide dismutase activity and levels of malondialdehyde were determined by UV spectrophotometry. The changes in mitochondrial membrane potential and the intracellular concentration of calcium were determined by flow cytometry, and the activity of caspase-3 was monitored by western blot. According to cell viability and apoptosis studies, MPP＋-induced apoptosis in PC12 cells was inhibited in the presence of 10 tJg/mL of Eleutheroside B Our results indicate that the neuroprotective effect of Eleutheroside B, following MPP＋-induced apoptosis in PC12 cells, involves increasing the anti-oxidative stress capacity of cells, maintaining the high-energy state of mitochondrial membrane potential, reducing intracellular calcium concentration and inhibiting caspase-3 activity.展开更多
Chinese Spallation Neutron Source(CSNS) has successfully produced its first neutron beam in 28th August 2017. It has been running steadily from March, 2018. According to the construction plan, the engineering material...Chinese Spallation Neutron Source(CSNS) has successfully produced its first neutron beam in 28th August 2017. It has been running steadily from March, 2018. According to the construction plan, the engineering materials diffractometer(EMD) will be installed between 2019–2023. This instrument requires the neutron detectors with the cover area near3 m2in two 90° neutron diffraction angle positions, the neutron detecting efficiency is better than 40%@1A, and the spatial resolution is better than 4 mm×200 mm in horizontal and vertical directions respectively. We have developed a onedimensional position-sensitive neutron detector based on the oblique6Li F/Zn S(Ag) scintillators, wavelength shifting fibers,and Si PMs(silicon photomultipliers) readout. The inhomogeneity of the neutron detection efficiency between each pixel and each detector module, which caused by the inconsistency of the wave-length shifting fibers in collecting scintillation photons, needs to be mitigated before the installation. A performance optimization experiment of the detector modules was carried out on the BL20(beam line 20) of CSNS. Using water sample, the neutron beam with Φ5 mm exit hole was dispersed related evenly into the forward space. According to the neutron counts of each pixel of the detector module, the readout electronics threshold of each pixel is adjusted. Compared with the unadjusted detector module, the inhomogeneity of the detection efficiency for the adjusted one has been improved from 69% to 90%. The test result of the diffraction peak of the standard sample Si showed that the adjusted detector module works well.展开更多
[Objectives]This study aimed to clone the tye A gene of Vibrio alginolyticus HY9901 strain and analyze its sequence by bioinformatics.[Methods] By referring to the entire genome sequence of Ⅴ.alginolyticus on Gen Ban...[Objectives]This study aimed to clone the tye A gene of Vibrio alginolyticus HY9901 strain and analyze its sequence by bioinformatics.[Methods] By referring to the entire genome sequence of Ⅴ.alginolyticus on Gen Bank,specific primers were designed.According to the principle of PCR amplification,the target gene tye A was amplified.By means of bioinformatics,the sequence of tye A was further analyzed,and the phylogenetic tree of tye A genes of Vibrio spp.and the corresponding subunit three-dimensional structure models were constructed.[Results] The length of the tye A gene of Ⅴ.alginolyticus strain HY9901 is 285 bp,and its theoretical molecular weight is 10.98 kD.According to prediction,there is no signal peptide or transmembrane region at the N-terminus of the sequence,and the amino acid sequence contains two casein kinase Ⅱ phosphorylation sites.The results of protein subcellular localization prediction show that the Tye A protein is located in the cell membrane.The protein is unstable and non-hydrophilic.The tertiary structure of Tye A protein of Ⅴ.alginolyticus is similar to that of Yersinia sp.According to prediction,Tye A has a major functional domain Pfam.In terms of secondary structure,alpha helix,random coil,extended strand and beta turn account for 85.11%,7.45%,4.26% and 3.19%,respectively.The homology of Tye A between Ⅴ.alginolyticus and Vibrio parahaemolyticus is up to 83%,so they are classified into one cluster.[Conclusions]This study will help to further understand the regulation mechanism of type Ⅲ secretion system in Ⅴ.alginolyticus.展开更多
[Objective]To clone araC gene of Vibrio alginolyticus HY9901 strain,and analyze bioinformatics.[Methods]the whole genome sequence of Vibrio alginolyticus on GenBank was used to design specific primers.According to the...[Objective]To clone araC gene of Vibrio alginolyticus HY9901 strain,and analyze bioinformatics.[Methods]the whole genome sequence of Vibrio alginolyticus on GenBank was used to design specific primers.According to the principle of PCR amplification sequence,the target gene araC was amplified,and then the sequence was further analyzed by bioinformatics method to establish the phylogenetic tree of araC gene and its corresponding subunit three-dimensional structure model.[Results]Sequence analysis revealed araC gene is 711 bp and encodes a putative protein of 236 amino acids.The predicted molecular mass of AraC was 26.92 ku.Using Signal P 4.0 and TMHMM Server 2.0 software for analysis,it was predicted that the AraC protein did not contain a signal peptide or a transmembranous region.The AraC protein had two cAMP and cGMP dependent protein kinase phosphorylation site,five protein kinase C phosphorylation sites,three casein kinase II phosphorylation sites,one prenyl group binding site(CAAX box)and five microbodies C-terminal targeting signal.The predicted results of protein subcellular localization showed that AraC was located in the mitochondria,nucleus and cytoplasm.Its protein is unstable and hydrophilic.The AraC protein is a transcriptional regulatory protein which belongs to HTH_18 superfamily.According to the prediction,secondary structure:a-helix(Alpha helix)accounted for 52.12%,random coil(31.78%),extended strand(11.02%),b-fold(Beta turn)accounted for 5.08%.V.alginolyticus,Vibrio parahaemolyticus and Vibrio palustris were clustered together,which implies that the genetic relationship between these three species was the closest.展开更多
[Objectives]To clone the pepck gene of Vibrio alginolyticus strain HY9901 and analyze its sequence by bioinformatics.[Methods]According to the complete gene sequence of V.alginolyticus on GenBank,specific primers were...[Objectives]To clone the pepck gene of Vibrio alginolyticus strain HY9901 and analyze its sequence by bioinformatics.[Methods]According to the complete gene sequence of V.alginolyticus on GenBank,specific primers were designed to amplify the target gene pepck by PCR.The sequence of the pepck gene was analyzed using bioinformatics.The phylogenic tree of pepck gene and the corresponding single-subunit three-dimensional structure were constructed.[Results]The pepck gene of V.alginolyticus strain HY9901 has a full length of 1629 bp,with theoretical molecular weight of 60.12 kD.The prediction results show that there is no signal peptide or transmembrane region at the N-terminus of the sequence,the amino acid sequence contains 11 phosphorylation sites of casein kinase II.The prediction results of protein subcellular localization indicate that PEPEK protein is localized in the cytoplasm.The protein is stable and hydrophobic.The tertiary structure of the PEPCK protein of V.alginolyticus is similar to that of Vibrio parahaemolyticus.It is predicted that PEPCK has a major functional domain PEPCK_ATP.In the secondary structure,alpha helix,random coil,and extended strand accounted for 21.96%,52.03%and 26.01%,respectively.The PEPCK homology between V.alginolyticus and Vibrio diabolicus is as high as 99%.[Conclusions]This study lays the foundation for further understanding the function of pepck gene in V.alginolyticus.展开更多
[Objectives] This study aimed to analyze the biological activity and immunogenicity of extracellular products from Streptococcus iniae .[Methods] S. iniae was incubated with brain heart infusion agar medium （BHIA ＋ ...[Objectives] This study aimed to analyze the biological activity and immunogenicity of extracellular products from Streptococcus iniae .[Methods] S. iniae was incubated with brain heart infusion agar medium （BHIA ＋ 4% calf serum） for 60 h. The bacterial liquid was rinsed with PBS, centrifuged, and filtered through microporous filtering film to collect extracellular products （ECPs）.[Results] Extracellular proteinase （ECPase） of S. iniae exhibited amylase, protease, lecitinase, gelatinase, lipase activities and hemolytic activity but had no urease activity. EDTA, DTT and PMSF could reduce ECPase activity to 72.4%, 77.6% and 72.4%, respectively. Cu^2＋ , Ca 2＋ , K^＋ and Mg^2＋ exhibited an inhibitory effect on ECPase activity, whereas Fe^3＋ , Co^2＋ and Mn^2＋ could activate ECPase activity. ECPs had good heat stability and exhibited relatively high activities under alkaline conditions. The optimal temperature for ECPs was 55 ℃. Two-dimensional electrophoresis was performed to analyze the main protein of ECPs. The results indicated that there are 12 main bands of ECPs, and the molecular weights mainly ranged between 28-68 kDa. About 120 protein spots were detected, and the molecular weights mainly ranged between 26-95 kDa. The mouse anti- S. iniae was used for Western-blot analysis of ECPs, and the results showed that there were four proteins, with molecular weights of 26, 37, 95, and 97 kDa, respectively. The pathogenicity assay indicated that ECPs of S. iniae were highly pathogenic to tilapia. The mortality rate of tilapia was enhanced as the concentration of ECPs increased.[Conclusions] This study provided a certain theoretical basis for revealing the pathogenic mechanism of Streptococcus iniae .展开更多
By imitating the behavioral characteristics of some typical animals, researchers develop bionic stepping motors to extend the working range of piezoelectric materials and utilize their high accuracy advantage as well....By imitating the behavioral characteristics of some typical animals, researchers develop bionic stepping motors to extend the working range of piezoelectric materials and utilize their high accuracy advantage as well. A comprehensive review of the bionic stepping motors driven by piezoelectric materials is presented in this work. The main parts of stepping piezoelectric motors, including the feeding module, clamping module, and other critical components, are introduced elaborately. We classify the bionic stepping piezoelectric motors into inchworm motors, seal motors, and inertia motors depending on their main structure modules, and present the mutual transformation relationships among the three types. In terms of the relative position relationships among the main structure modules, each of the inchworm motors, seal motors, and inertia motors can further be divided into walker type, pusher type, and hybrid type. The configurations and working principles of all bionic stepping piezoelectric motors are reported, followed by a discussion of the advantages and disadvantages of the performance for each type. This work provides theoretical support and thoughtful insights for the understanding, analysis, design, and application of the bionic stepping piezoelectric motors.展开更多
基金Supported by the National Natural Science Foundation of China(No.U1612442)the Science and Technology Foundation of Guizhou Province(Nos.[2020]6009,[2020]4Y009)Anton Brancelj was supported by Slovenian Research Agency(ARRS)(No.P1-0255)。
文摘Reservoirs are an important water source in many densely populated areas in southwest China.Phytoplankton play an essential role in maintaining the structure and function of reservoir ecosystems.Understanding the succession in phytoplankton communities and the factors driving it are essential for eff ective water quality management in drinking water reservoirs.In this study,water samples were collected monthly at the surface layers from March 2016 to December 2019 in Hongfeng Reservoir,southwest China.The relationship between functional group succession was analyzed based on nonmetric multidimensional scaling analysis(NMDS),redundancy analysis(RDA),succession rate,and other analysis methods.The results showed distinct shifts in the community structure of phytoplankton functional groups within study period.The Cyclotella sp.was dominant in 2016 and 2017,and Pseudanabaena limnetica was the dominant group in 2018 and 2019.It appears that the phytoplankton composition and biomass are closely related to the water temperature and nutrient status in this reservoir.The results clearly showed that the permanganate index(COD_(Mn))was the key factor of dramatic phytoplankton functional group succession,and the change in succession rates was closely caused by total nitrogen concentration(TN).Therefore,the succession pattern and key factors of Hongfeng Reservoir revealed in this study were important guidance for the management of drinking water reservoirs in southwest China.A reasonable limit on exogenous nutrient input should be a priority,especially in high water temperature period.
基金National Natural Science Foundation of China(32073015).
文摘[Objectives]The purpose was to investigate the function and mechanism of exsA gene in type III secretion system of Vibrio alginolyticus.[Methods]The full length of exsA was cloned using molecular biology techniques to analyze its biological information.Fluorescence quantitative PCR technology was used to analyze the expression of exsA after different media stress.[Results]The exsA gene contains an open reading frame(ORF)of 861 bp,encoding 286 amino acids.The physico-chemical analysis shows that the molecular structural formula is C1442H2267N393O441S12,the theoretical molecular weight is 32.549 kD,the theoretical pI value is 6.0,and the protein is non-hydrophilic and unstable.The gene does not contain a transmembrane region,and there is no obvious signal peptide.The prediction result of protein subcellular localization shows that the protein is inside the cell.The deduced amino acid sequence and constructed phylogenetic tree show that V.alginolyticus has a close relationship with Vibrio antiquarius.The qPCR results show that the expression level of exsA in different media is different,highest in TSB medium containing bile salts,followed by DMEM medium,and lowest in ordinary TSB medium.[Conclusions]The gene sequence,molecular structure and isoelectric point of exsA,as well as its expression in three different media were obtained.
基金the Major Projects of National Science and Technology, No.2009ZX09103-329the National Natural Science Foundation for Distinguished Young Scholars of China, No.30901974+1 种基金Outstanding Youth Science Fund Program of Heilongjiang Province, No.JC200705"Spring Sunshine" Plan of Ministry of Education, No.2006
文摘Apoptosis and viability of PC12 cells following 1-methyl-4-phenylpyridinium ion （MPP＋）-induced injury were monitored by flow cytometry, following Annexin V-propidium iodide double labeling, and 3-（4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay, respectively. The release of lactate dehydrogenase, superoxide dismutase activity and levels of malondialdehyde were determined by UV spectrophotometry. The changes in mitochondrial membrane potential and the intracellular concentration of calcium were determined by flow cytometry, and the activity of caspase-3 was monitored by western blot. According to cell viability and apoptosis studies, MPP＋-induced apoptosis in PC12 cells was inhibited in the presence of 10 tJg/mL of Eleutheroside B Our results indicate that the neuroprotective effect of Eleutheroside B, following MPP＋-induced apoptosis in PC12 cells, involves increasing the anti-oxidative stress capacity of cells, maintaining the high-energy state of mitochondrial membrane potential, reducing intracellular calcium concentration and inhibiting caspase-3 activity.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11975255 and 11875273)Guangdong Basic and Applied Basic Research Foundation (Grant No. 2020B1515120025)。
文摘Chinese Spallation Neutron Source(CSNS) has successfully produced its first neutron beam in 28th August 2017. It has been running steadily from March, 2018. According to the construction plan, the engineering materials diffractometer(EMD) will be installed between 2019–2023. This instrument requires the neutron detectors with the cover area near3 m2in two 90° neutron diffraction angle positions, the neutron detecting efficiency is better than 40%@1A, and the spatial resolution is better than 4 mm×200 mm in horizontal and vertical directions respectively. We have developed a onedimensional position-sensitive neutron detector based on the oblique6Li F/Zn S(Ag) scintillators, wavelength shifting fibers,and Si PMs(silicon photomultipliers) readout. The inhomogeneity of the neutron detection efficiency between each pixel and each detector module, which caused by the inconsistency of the wave-length shifting fibers in collecting scintillation photons, needs to be mitigated before the installation. A performance optimization experiment of the detector modules was carried out on the BL20(beam line 20) of CSNS. Using water sample, the neutron beam with Φ5 mm exit hole was dispersed related evenly into the forward space. According to the neutron counts of each pixel of the detector module, the readout electronics threshold of each pixel is adjusted. Compared with the unadjusted detector module, the inhomogeneity of the detection efficiency for the adjusted one has been improved from 69% to 90%. The test result of the diffraction peak of the standard sample Si showed that the adjusted detector module works well.
基金Supported by Natural Science Foundation of Guangdong Province(2017A030313174)"Sail of the Sea-Starting Plan" of Guangdong Ocean University(qhjhzr201813)Innovation and Entrepreneurship Training Program for College Students(No.CXXL2019041)
文摘[Objectives]This study aimed to clone the tye A gene of Vibrio alginolyticus HY9901 strain and analyze its sequence by bioinformatics.[Methods] By referring to the entire genome sequence of Ⅴ.alginolyticus on Gen Bank,specific primers were designed.According to the principle of PCR amplification,the target gene tye A was amplified.By means of bioinformatics,the sequence of tye A was further analyzed,and the phylogenetic tree of tye A genes of Vibrio spp.and the corresponding subunit three-dimensional structure models were constructed.[Results] The length of the tye A gene of Ⅴ.alginolyticus strain HY9901 is 285 bp,and its theoretical molecular weight is 10.98 kD.According to prediction,there is no signal peptide or transmembrane region at the N-terminus of the sequence,and the amino acid sequence contains two casein kinase Ⅱ phosphorylation sites.The results of protein subcellular localization prediction show that the Tye A protein is located in the cell membrane.The protein is unstable and non-hydrophilic.The tertiary structure of Tye A protein of Ⅴ.alginolyticus is similar to that of Yersinia sp.According to prediction,Tye A has a major functional domain Pfam.In terms of secondary structure,alpha helix,random coil,extended strand and beta turn account for 85.11%,7.45%,4.26% and 3.19%,respectively.The homology of Tye A between Ⅴ.alginolyticus and Vibrio parahaemolyticus is up to 83%,so they are classified into one cluster.[Conclusions]This study will help to further understand the regulation mechanism of type Ⅲ secretion system in Ⅴ.alginolyticus.
基金National Natural Science Foundation of China(32073015).
文摘[Objective]To clone araC gene of Vibrio alginolyticus HY9901 strain,and analyze bioinformatics.[Methods]the whole genome sequence of Vibrio alginolyticus on GenBank was used to design specific primers.According to the principle of PCR amplification sequence,the target gene araC was amplified,and then the sequence was further analyzed by bioinformatics method to establish the phylogenetic tree of araC gene and its corresponding subunit three-dimensional structure model.[Results]Sequence analysis revealed araC gene is 711 bp and encodes a putative protein of 236 amino acids.The predicted molecular mass of AraC was 26.92 ku.Using Signal P 4.0 and TMHMM Server 2.0 software for analysis,it was predicted that the AraC protein did not contain a signal peptide or a transmembranous region.The AraC protein had two cAMP and cGMP dependent protein kinase phosphorylation site,five protein kinase C phosphorylation sites,three casein kinase II phosphorylation sites,one prenyl group binding site(CAAX box)and five microbodies C-terminal targeting signal.The predicted results of protein subcellular localization showed that AraC was located in the mitochondria,nucleus and cytoplasm.Its protein is unstable and hydrophilic.The AraC protein is a transcriptional regulatory protein which belongs to HTH_18 superfamily.According to the prediction,secondary structure:a-helix(Alpha helix)accounted for 52.12%,random coil(31.78%),extended strand(11.02%),b-fold(Beta turn)accounted for 5.08%.V.alginolyticus,Vibrio parahaemolyticus and Vibrio palustris were clustered together,which implies that the genetic relationship between these three species was the closest.
基金Shenzhen Science and Technology Project(JCYJ2019081310-4207152,JCYJ20170818111629778)Undergraduate Innovative and Entrepreneurial Team Project。
文摘[Objectives]To clone the pepck gene of Vibrio alginolyticus strain HY9901 and analyze its sequence by bioinformatics.[Methods]According to the complete gene sequence of V.alginolyticus on GenBank,specific primers were designed to amplify the target gene pepck by PCR.The sequence of the pepck gene was analyzed using bioinformatics.The phylogenic tree of pepck gene and the corresponding single-subunit three-dimensional structure were constructed.[Results]The pepck gene of V.alginolyticus strain HY9901 has a full length of 1629 bp,with theoretical molecular weight of 60.12 kD.The prediction results show that there is no signal peptide or transmembrane region at the N-terminus of the sequence,the amino acid sequence contains 11 phosphorylation sites of casein kinase II.The prediction results of protein subcellular localization indicate that PEPEK protein is localized in the cytoplasm.The protein is stable and hydrophobic.The tertiary structure of the PEPCK protein of V.alginolyticus is similar to that of Vibrio parahaemolyticus.It is predicted that PEPCK has a major functional domain PEPCK_ATP.In the secondary structure,alpha helix,random coil,and extended strand accounted for 21.96%,52.03%and 26.01%,respectively.The PEPCK homology between V.alginolyticus and Vibrio diabolicus is as high as 99%.[Conclusions]This study lays the foundation for further understanding the function of pepck gene in V.alginolyticus.
基金Supported by Natural Science Foundation of Guangdong Province(2017A030313174)Natural Science Foundation of Guangdong Ocean University(C17379)+2 种基金Undergraduate Innovative and Entrepreneurial Team Project(CCTD201802)Science and Technology Program of Guangdong Province(2015A020209163)Special Fund for Construction of Fishery Port and Development of Fishery Industry of Guangdong Province(A201708A05)
文摘[Objectives] This study aimed to analyze the biological activity and immunogenicity of extracellular products from Streptococcus iniae .[Methods] S. iniae was incubated with brain heart infusion agar medium （BHIA ＋ 4% calf serum） for 60 h. The bacterial liquid was rinsed with PBS, centrifuged, and filtered through microporous filtering film to collect extracellular products （ECPs）.[Results] Extracellular proteinase （ECPase） of S. iniae exhibited amylase, protease, lecitinase, gelatinase, lipase activities and hemolytic activity but had no urease activity. EDTA, DTT and PMSF could reduce ECPase activity to 72.4%, 77.6% and 72.4%, respectively. Cu^2＋ , Ca 2＋ , K^＋ and Mg^2＋ exhibited an inhibitory effect on ECPase activity, whereas Fe^3＋ , Co^2＋ and Mn^2＋ could activate ECPase activity. ECPs had good heat stability and exhibited relatively high activities under alkaline conditions. The optimal temperature for ECPs was 55 ℃. Two-dimensional electrophoresis was performed to analyze the main protein of ECPs. The results indicated that there are 12 main bands of ECPs, and the molecular weights mainly ranged between 28-68 kDa. About 120 protein spots were detected, and the molecular weights mainly ranged between 26-95 kDa. The mouse anti- S. iniae was used for Western-blot analysis of ECPs, and the results showed that there were four proteins, with molecular weights of 26, 37, 95, and 97 kDa, respectively. The pathogenicity assay indicated that ECPs of S. iniae were highly pathogenic to tilapia. The mortality rate of tilapia was enhanced as the concentration of ECPs increased.[Conclusions] This study provided a certain theoretical basis for revealing the pathogenic mechanism of Streptococcus iniae .
基金Natural Science Foundation of Jilin Province,20220101216JC,Shupeng WangTalent Introduction Fund of Jilin University,451210330007,Shupeng Wang.
文摘By imitating the behavioral characteristics of some typical animals, researchers develop bionic stepping motors to extend the working range of piezoelectric materials and utilize their high accuracy advantage as well. A comprehensive review of the bionic stepping motors driven by piezoelectric materials is presented in this work. The main parts of stepping piezoelectric motors, including the feeding module, clamping module, and other critical components, are introduced elaborately. We classify the bionic stepping piezoelectric motors into inchworm motors, seal motors, and inertia motors depending on their main structure modules, and present the mutual transformation relationships among the three types. In terms of the relative position relationships among the main structure modules, each of the inchworm motors, seal motors, and inertia motors can further be divided into walker type, pusher type, and hybrid type. The configurations and working principles of all bionic stepping piezoelectric motors are reported, followed by a discussion of the advantages and disadvantages of the performance for each type. This work provides theoretical support and thoughtful insights for the understanding, analysis, design, and application of the bionic stepping piezoelectric motors.
