[Objective] To explore the feasibility of using SYBR Green real-time quantitative PCR technique to estimate the copy numbers of exogenous gene in a transgenic plant.[Methods] Using SYBR Green real-time quantitative PC...[Objective] To explore the feasibility of using SYBR Green real-time quantitative PCR technique to estimate the copy numbers of exogenous gene in a transgenic plant.[Methods] Using SYBR Green real-time quantitative PCR technique,we have determined the copy numbers of the exogenous CYCD3;1 in transgenic Arabidopsis by comparing an endogenous single copy reference gene with CYCD3;1 copy numbers in transgenic plant,meanwhile comparing CYCD3;1 copy numbers between wild plant and transgenic plant.[Results]The exogenous CYCD3;1 copy numbers calculated by this method is identical with results of traditional Southern blot analysis which is highly accurate.[Conclusion]This method is simple,effective and safe for estimating transgene copy numbers.展开更多
Network intrusion poses a severe threat to the Internet.However,existing intrusion detection models cannot effectively distinguish different intrusions with high-degree feature overlap.In addition,efficient real-time ...Network intrusion poses a severe threat to the Internet.However,existing intrusion detection models cannot effectively distinguish different intrusions with high-degree feature overlap.In addition,efficient real-time detection is an urgent problem.To address the two above problems,we propose a Latent Dirichlet Allocation topic model-based framework for real-time network Intrusion Detection(LDA-ID),consisting of static and online LDA-ID.The problem of feature overlap is transformed into static LDA-ID topic number optimization and topic selection.Thus,the detection is based on the latent topic features.To achieve efficient real-time detection,we design an online computing mode for static LDA-ID,in which a parameter iteration method based on momentum is proposed to balance the contribution of prior knowledge and new information.Furthermore,we design two matching mechanisms to accommodate the static and online LDA-ID,respectively.Experimental results on the public NSL-KDD and UNSW-NB15 datasets show that our framework gets higher accuracy than the others.展开更多
[Objective] This study aimed to establish a Real-Time quantitative PCR method for the determination of transposon copy number in C. sakazakii. [ Method ] With single-copy housekeeping gene atpD as the reference gene, ...[Objective] This study aimed to establish a Real-Time quantitative PCR method for the determination of transposon copy number in C. sakazakii. [ Method ] With single-copy housekeeping gene atpD as the reference gene, recombinant plasmid containing both single-copy housekeeping gene atpD and EZ-TN5 transposon was constructed; based on the established standard curves for real-time quantitative detection of atpD gene and EZ-TN5 transposon, copy number of atpD gene and EZ-TN5 transpason in three C. sakazakii mutants was detected and the ratio was calculated. [ Result] Correlation coefficients of the standard curves for real-time quantitative detection of atpD gene and EZ-TN5 transposon were 0. 999 and 0.998, respectively ; the ratios of copy number of atpD gene and EZ-TN5 transposon in three C. sakazakii mutants were 0.98, 1.17 and 0.91, respectively, which indicates that EZ-TN5 transpeson in C. sakakii mutants is a single-copy. [ Conclusion] Real-time quantitative PCR method established in this study had high availability and could replace the Southern blot method to detect the copy num- ber of EZ-TN5 transposon in different bacteria.展开更多
Current public-opinion propagation research usually focused on closed network topologies without considering the fluctuation of the number of network users or the impact of social factors on propagation. Thus, it rema...Current public-opinion propagation research usually focused on closed network topologies without considering the fluctuation of the number of network users or the impact of social factors on propagation. Thus, it remains difficult to accurately describe the public-opinion propagation rules of social networks. In order to study the rules of public opinion spread on dynamic social networks, by analyzing the activity of social-network users and the regulatory role of relevant departments in the spread of public opinion, concepts of additional user and offline rates are introduced, and the direct immune-susceptible, contacted, infected, and refractory (DI-SCIR) public-opinion propagation model based on real-time online users is established. The interventional force of relevant departments, credibility of real information, and time of intervention are considered, and a public-opinion propagation control strategy based on direct immunity is proposed. The equilibrium point and the basic reproduction number of the model are theoretically analyzed to obtain boundary conditions for public-opinion propagation. Simulation results show that the new model can accurately reflect the propagation rules of public opinion. When the basic reproduction number is less than 1, public opinion will eventually disappear in the network. Social factors can significantly influence the time and scope of public opinion spread on social networks. By controlling social factors, relevant departments can analyze the rules of public opinion spread on social networks to suppress the propagate of negative public opinion and provide a powerful tool to ensure security and stability of society.展开更多
Objective:To identify prevalence of chloroquine resistance point mutation at(Pfcrt,K76T)and(Pfindr1.N86Y) copy number variation.Methods:SYBR Green I based real time PCR was used.One hundred and thirty-three samples we...Objective:To identify prevalence of chloroquine resistance point mutation at(Pfcrt,K76T)and(Pfindr1.N86Y) copy number variation.Methods:SYBR Green I based real time PCR was used.One hundred and thirty-three samples were analyzed for(Pfcrt,K76T) and(Pfmdr1.N86Y) copy number from dried blood spot.Parasite DNA was extracted using high pure DNA preparation kit.The amplification of DNA was done by using AccuPower 2* GreenStar '' qPCR Master mix.For quantification purpose a new primer pair was designed for 178 base pair template from complete genome sequence of Plasmodium falciparum strain 3D7 at NCBI.Absolute quantification method was used to determine the Pfmdr1-N86 Y copy number variations.Standard curve was built from strain3D7 gDNA since it has single copy of Pfindr1 per haploid genome.The known positive controls with single and multi-copy number of Pfindr1 gene were included in each experiment.The copy number ratio of the samples to the standard calibrator was made to obtain the fold difference among the samples with respect to copy number variation.Results:Out of 133 samples 73(54.89%) were confirmed as mutant(Pfcrt,76T) and the remaining 60(45.11%) were genotyped as wild type(Pfcrt,K76).The(Pfindr1.N86Y) copy number variation was determined for 133 clinical samples.Out of these samples 61(45.86%)had single copy and the remaining 72(54.14%) had multi-copy numbers higher than 1.5 copies per genome.Thirty-four(25.56%) multi-copies were between 1.5 and 2.5 copies per genome while 38(28.57%) were more than 2.5 copies per genome.The minimum and maximum copies per genome were 0.474 and 4.741.respectively.Conclusions:The study showed high prevalence level and fixation of Pfcrt.76 T mutation after chloroquine withdrawal.The prevalence of Pfindr1 copy number variant suggested that the presence of modulating factor for emergence of Plasmodium falciparum strains with higher copy numbers.However,the prevalence level was not statistically significant.展开更多
This work proposes a method for the detection and identification of parked vehicles stationed. This technique composed many algorithms for the detection, localization, segmentation, extraction and recognition of numbe...This work proposes a method for the detection and identification of parked vehicles stationed. This technique composed many algorithms for the detection, localization, segmentation, extraction and recognition of number plates in images. It is acts of a technology of image processing used to identify the vehicles by their number plates. Knowing that we work on images whose level of gray is sampled with (120×180), resulting from a base of abundant data by PSA. We present two algorithms allowing the detection of the horizontal position of the vehicle: the classical method “horizontal gradients” and our approach “symmetrical method”. In fact, a car seen from the front presents a symmetry plan and by detecting its axis, that one finds its position in the image. A phase of localization is treated using the parameter MGD (Maximum Gradient Difference) which allows locating all the segments of text per horizontal scan. A specific technique of filtering, combining the method of symmetry and the localization by the MGD allows eliminating the blocks which don’t pass by the axis of symmetry and thus find the good block containing the number plate. Once we locate the plate, we use four algorithms that must be realized in order to allow our system to identify a license plate. The first algorithm is adjusting the intensity and the contrast of the image. The second algorithm is segmenting the characters on the plate using profile method. Then extracting and resizing the characters and finally recognizing them by means of optical character recogni-tion OCR. The efficiency of these algorithms is shown using a database of 350 images for the tests. We find a rate of lo-calization of 99.6% on a basis of 350 images with a rate of false alarms (wrong block text) of 0.88% by image.展开更多
辛烷值对维持汽油机的理想运转起到重要作用。该文用整车转鼓试验,研究了辛烷值对现代汽油车燃油经济性及排放的影响。5辆试验汽车分别采用缸内直喷(gasoline direct injection,GDI)与进气道喷射(port fuel injection,PFI)2种发...辛烷值对维持汽油机的理想运转起到重要作用。该文用整车转鼓试验,研究了辛烷值对现代汽油车燃油经济性及排放的影响。5辆试验汽车分别采用缸内直喷(gasoline direct injection,GDI)与进气道喷射(port fuel injection,PFI)2种发动机和涡轮增压与自然吸气2种技术,采用研究法辛烷值(RON)为91.9~98.4的6种汽油,在新欧洲驾驶循环(NEDC)条件下进行试验。结果表明:采用先进技术的汽车,使用高辛烷值汽油时,节油效果明显:RON每提升1个单位,车辆燃油经济性可提升约1%;辛烷值较高(RON为97)时的汽车获得节油效果约为辛烷值较低(RON为93)时的2倍。提高辛烷值,可不同程度改善排放。展开更多
基金Supported by National Natural Science Foundation Project(30270086)~~
文摘[Objective] To explore the feasibility of using SYBR Green real-time quantitative PCR technique to estimate the copy numbers of exogenous gene in a transgenic plant.[Methods] Using SYBR Green real-time quantitative PCR technique,we have determined the copy numbers of the exogenous CYCD3;1 in transgenic Arabidopsis by comparing an endogenous single copy reference gene with CYCD3;1 copy numbers in transgenic plant,meanwhile comparing CYCD3;1 copy numbers between wild plant and transgenic plant.[Results]The exogenous CYCD3;1 copy numbers calculated by this method is identical with results of traditional Southern blot analysis which is highly accurate.[Conclusion]This method is simple,effective and safe for estimating transgene copy numbers.
基金supported by the National Natural Science Foundation of China(Grant No.U1636208,No.61862008,No.61902013)the Beihang Youth Top Talent Support Program(Grant No.YWF-21-BJJ-1039)。
文摘Network intrusion poses a severe threat to the Internet.However,existing intrusion detection models cannot effectively distinguish different intrusions with high-degree feature overlap.In addition,efficient real-time detection is an urgent problem.To address the two above problems,we propose a Latent Dirichlet Allocation topic model-based framework for real-time network Intrusion Detection(LDA-ID),consisting of static and online LDA-ID.The problem of feature overlap is transformed into static LDA-ID topic number optimization and topic selection.Thus,the detection is based on the latent topic features.To achieve efficient real-time detection,we design an online computing mode for static LDA-ID,in which a parameter iteration method based on momentum is proposed to balance the contribution of prior knowledge and new information.Furthermore,we design two matching mechanisms to accommodate the static and online LDA-ID,respectively.Experimental results on the public NSL-KDD and UNSW-NB15 datasets show that our framework gets higher accuracy than the others.
基金Supported by Key Project of Tianjin Municipal Education Commission(2010ZD01)
文摘[Objective] This study aimed to establish a Real-Time quantitative PCR method for the determination of transposon copy number in C. sakazakii. [ Method ] With single-copy housekeeping gene atpD as the reference gene, recombinant plasmid containing both single-copy housekeeping gene atpD and EZ-TN5 transposon was constructed; based on the established standard curves for real-time quantitative detection of atpD gene and EZ-TN5 transposon, copy number of atpD gene and EZ-TN5 transpason in three C. sakazakii mutants was detected and the ratio was calculated. [ Result] Correlation coefficients of the standard curves for real-time quantitative detection of atpD gene and EZ-TN5 transposon were 0. 999 and 0.998, respectively ; the ratios of copy number of atpD gene and EZ-TN5 transposon in three C. sakazakii mutants were 0.98, 1.17 and 0.91, respectively, which indicates that EZ-TN5 transpeson in C. sakakii mutants is a single-copy. [ Conclusion] Real-time quantitative PCR method established in this study had high availability and could replace the Southern blot method to detect the copy num- ber of EZ-TN5 transposon in different bacteria.
基金Project supported by the National Natural Science Foundation of China (Grant No. 61471080)the Equipment Development Department Research Foundation of China (Grant No. 61400010303)+2 种基金the Natural Science Research Project of Liaoning Education Department of China (Grant Nos. JDL2019019 and JDL2020002)the Surface Project for Natural Science Foundation in Guangdong Province of China (Grant No. 2019A1515011164)the Science and Technology Plan Project in Zhanjiang, China (Grant No. 2018A06001)。
文摘Current public-opinion propagation research usually focused on closed network topologies without considering the fluctuation of the number of network users or the impact of social factors on propagation. Thus, it remains difficult to accurately describe the public-opinion propagation rules of social networks. In order to study the rules of public opinion spread on dynamic social networks, by analyzing the activity of social-network users and the regulatory role of relevant departments in the spread of public opinion, concepts of additional user and offline rates are introduced, and the direct immune-susceptible, contacted, infected, and refractory (DI-SCIR) public-opinion propagation model based on real-time online users is established. The interventional force of relevant departments, credibility of real information, and time of intervention are considered, and a public-opinion propagation control strategy based on direct immunity is proposed. The equilibrium point and the basic reproduction number of the model are theoretically analyzed to obtain boundary conditions for public-opinion propagation. Simulation results show that the new model can accurately reflect the propagation rules of public opinion. When the basic reproduction number is less than 1, public opinion will eventually disappear in the network. Social factors can significantly influence the time and scope of public opinion spread on social networks. By controlling social factors, relevant departments can analyze the rules of public opinion spread on social networks to suppress the propagate of negative public opinion and provide a powerful tool to ensure security and stability of society.
基金Supported by the Pan African University Institute of Basic Science Innovation and Technology(Grant No.132)
文摘Objective:To identify prevalence of chloroquine resistance point mutation at(Pfcrt,K76T)and(Pfindr1.N86Y) copy number variation.Methods:SYBR Green I based real time PCR was used.One hundred and thirty-three samples were analyzed for(Pfcrt,K76T) and(Pfmdr1.N86Y) copy number from dried blood spot.Parasite DNA was extracted using high pure DNA preparation kit.The amplification of DNA was done by using AccuPower 2* GreenStar '' qPCR Master mix.For quantification purpose a new primer pair was designed for 178 base pair template from complete genome sequence of Plasmodium falciparum strain 3D7 at NCBI.Absolute quantification method was used to determine the Pfmdr1-N86 Y copy number variations.Standard curve was built from strain3D7 gDNA since it has single copy of Pfindr1 per haploid genome.The known positive controls with single and multi-copy number of Pfindr1 gene were included in each experiment.The copy number ratio of the samples to the standard calibrator was made to obtain the fold difference among the samples with respect to copy number variation.Results:Out of 133 samples 73(54.89%) were confirmed as mutant(Pfcrt,76T) and the remaining 60(45.11%) were genotyped as wild type(Pfcrt,K76).The(Pfindr1.N86Y) copy number variation was determined for 133 clinical samples.Out of these samples 61(45.86%)had single copy and the remaining 72(54.14%) had multi-copy numbers higher than 1.5 copies per genome.Thirty-four(25.56%) multi-copies were between 1.5 and 2.5 copies per genome while 38(28.57%) were more than 2.5 copies per genome.The minimum and maximum copies per genome were 0.474 and 4.741.respectively.Conclusions:The study showed high prevalence level and fixation of Pfcrt.76 T mutation after chloroquine withdrawal.The prevalence of Pfindr1 copy number variant suggested that the presence of modulating factor for emergence of Plasmodium falciparum strains with higher copy numbers.However,the prevalence level was not statistically significant.
文摘This work proposes a method for the detection and identification of parked vehicles stationed. This technique composed many algorithms for the detection, localization, segmentation, extraction and recognition of number plates in images. It is acts of a technology of image processing used to identify the vehicles by their number plates. Knowing that we work on images whose level of gray is sampled with (120×180), resulting from a base of abundant data by PSA. We present two algorithms allowing the detection of the horizontal position of the vehicle: the classical method “horizontal gradients” and our approach “symmetrical method”. In fact, a car seen from the front presents a symmetry plan and by detecting its axis, that one finds its position in the image. A phase of localization is treated using the parameter MGD (Maximum Gradient Difference) which allows locating all the segments of text per horizontal scan. A specific technique of filtering, combining the method of symmetry and the localization by the MGD allows eliminating the blocks which don’t pass by the axis of symmetry and thus find the good block containing the number plate. Once we locate the plate, we use four algorithms that must be realized in order to allow our system to identify a license plate. The first algorithm is adjusting the intensity and the contrast of the image. The second algorithm is segmenting the characters on the plate using profile method. Then extracting and resizing the characters and finally recognizing them by means of optical character recogni-tion OCR. The efficiency of these algorithms is shown using a database of 350 images for the tests. We find a rate of lo-calization of 99.6% on a basis of 350 images with a rate of false alarms (wrong block text) of 0.88% by image.
文摘辛烷值对维持汽油机的理想运转起到重要作用。该文用整车转鼓试验,研究了辛烷值对现代汽油车燃油经济性及排放的影响。5辆试验汽车分别采用缸内直喷(gasoline direct injection,GDI)与进气道喷射(port fuel injection,PFI)2种发动机和涡轮增压与自然吸气2种技术,采用研究法辛烷值(RON)为91.9~98.4的6种汽油,在新欧洲驾驶循环(NEDC)条件下进行试验。结果表明:采用先进技术的汽车,使用高辛烷值汽油时,节油效果明显:RON每提升1个单位,车辆燃油经济性可提升约1%;辛烷值较高(RON为97)时的汽车获得节油效果约为辛烷值较低(RON为93)时的2倍。提高辛烷值,可不同程度改善排放。