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Cloning and Expression Vector Construction of BnZAT12 in Brassica napus
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作者 HUANG Xin ZHOU Li-hua +3 位作者 YUAN Yu-hui ZHONG Kai CHEN Dong-long LIU Xian-jun 《Agricultural Science & Technology》 2025年第1期45-54,共10页
To investigate the function of the zinc finger protein BnZAT12 in Brassica napus,bioinformatics analysis was conducted on BnZAT12.The results showed that the open reading frame of BnZAT12 was 477 bp in length,encoding... To investigate the function of the zinc finger protein BnZAT12 in Brassica napus,bioinformatics analysis was conducted on BnZAT12.The results showed that the open reading frame of BnZAT12 was 477 bp in length,encoding 158 amino acid residues.The deduced protein had a molecular weight of 16864.72 Da and a theoretical isoelectric point of 9.68.The phylogenetic tree showed that Brassica napus had the closest relationship with Brassica oleracea belonging to Brassicaceae and the farthest relationship with Oryza sativa.The analysis of the promoter region suggested that BnZAT12 may be regulated by factors such as light,abscisic acid,and methyl jasmonate.Furthermore,the BnZAT12 overexpression vector was constructed by seamless cloning.This study laid a foundation of molecular biology for further elucidating the role of BnZAT12. 展开更多
关键词 BnZAT12 Brassica napus Bioinformatics analysis vector construction
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Cloning and Expression Vector Construction of BnOPR1 from Brassica napus
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作者 CHENG Yi-yuan YUAN Yu-hui +5 位作者 WANG Yan-hong GONG Sha LING Hui HUANG Jing-yi ZHONG Pin-tian LIU Xian-jun 《Agricultural Science & Technology》 2025年第3期6-14,共9页
The 12-oxophytodienoate reductase(OPR),a flavin mononucleotide-dependent oxidoreductase,regulates plant responses to stress conditions such as heavy metals,drought,saline-alkali,pests,and diseases by participating in ... The 12-oxophytodienoate reductase(OPR),a flavin mononucleotide-dependent oxidoreductase,regulates plant responses to stress conditions such as heavy metals,drought,saline-alkali,pests,and diseases by participating in the synthesis of plant hormones such as jasmonic acid(JA).In this study,homologous cloning was employed to obtain the Brassica napus‘Zhongshuang 11’OPR1 gene(BnOPR1).Bioinformatics analysis was conducted for the deduced protein BnOPR1,and a plant expression vector for BnOPR1 was constructed.The bioinformatics analysis revealed that BnOPR1 was 1125 bp in length,encoding 375 amino acid residues.The deduced protein had a molecular weight of 41.604 kDa,an isoelectric point of 6.05,a molecular formula of C1853H2855N511O550S16,an aliphatic index of 35.47,a lipophilicity index of 74.87,and an instability index of 39.49.It had 49 phosphorylation sites and lacked transmembrane domains and signal peptides.The phylogenetic analysis indicated that BnOPR1 had a close relationship with the OPR1 protein from Brassica rapa since they shared the same clade,while it had a distant relationship with the OPR1 protein from Raphanus sativus.In this paper,the expression vector for BnOPR1 was successfully constructed by seamless cloning and named pBnOPR1.The findings laid a foundation for further studying the roles of BnOPR1 in the response to antimony stress. 展开更多
关键词 Brassica napus BnOPR1 gene Homologous cloning vector construction
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Speed Sensorless Vector Control of Induction Motor Based on Reduced Order Extended Kalman Filter 被引量:1
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作者 杨文强 贾正春 许强 《Journal of Southeast University(English Edition)》 EI CAS 2001年第1期41-45,共5页
A speed sensorless vector control system of induction motor with estimated rotor speed and rotor flux using a new reduced order extended Kalman filter is proposed. With this method, two rotor flux components are sele... A speed sensorless vector control system of induction motor with estimated rotor speed and rotor flux using a new reduced order extended Kalman filter is proposed. With this method, two rotor flux components are selected as the state variables, and the rotor speed as an estimated parameter is regarded as an augmented state variable. The algorithm with reduced order decreases the computational complexity and makes the proposed estimator feasible to be implemented in real time. The simulation results show high accuracy of the estimation algorithm and good performance of speed control, and verify the usefulness of the proposed algorithm. 展开更多
关键词 extended Kalman filter flux estimation speed estimation speed sensorless vector control induction motor
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New adaptive vector control methods for induction motors with simpler structure and better performance 被引量:1
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作者 Kang-Zhi LIU Masashi YOKOO +1 位作者 Keiichiro KONDO Tadanao ZANMA 《Control Theory and Technology》 EI CSCD 2015年第2期173-183,共3页
This paper deals with the vector control, including both the direct vector control(DVC) and the indirect vector control(Id VC),of induction motors. It is well known that the estimation of rotor flux plays a fundamenta... This paper deals with the vector control, including both the direct vector control(DVC) and the indirect vector control(Id VC),of induction motors. It is well known that the estimation of rotor flux plays a fundamental role in the DVC and the estimation of rotor resistance is vital in the slip compensation of the Id VC. In these estimations, the precision is significantly affected by the motor resistances. Therefore, online estimation of motor resistances is indispensable in practice.For a fast estimation of motor resistances, it is necessary to slow down the convergence rate of the current estimate. On the other hand, for a fast estimation of the rotor flux, it is necessary to speed up its convergence rate. It is very difficult to realize such a trade-off in convergence rates in a full order observer.In this paper, we propose to decouple the current observer from the flux observer so as to realize independent convergence rates. Then, the resistance estimation algorithm is applied to both DVC and Id VC. In particular, in the application to Id VC the flux observer needs not be used, which leads to a simpler structure. Meanwhile, independent convergence rates of current observer and flux observer yield an improved performance. A superior performance in the torque and flux responses in both cases is verified by numerous simulations. 展开更多
关键词 Induction motor current observer flux observer parameter adaptation indirect vector control direct vector control
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Construction of Recombinant Adenovirus Vector Containing CEVB2L Gene 被引量:2
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作者 邵洪泽 毛文智 +4 位作者 宋阳 李琳 程荣华 孙健 孙强 《Agricultural Science & Technology》 CAS 2010年第3期94-97,共4页
[Objective] Sheep contagious ecthyma virus B2L gene recombinant adenovirus was built by adenovirus vector system.[Method] Genome DNA extracted from sheep contagious ecthyma virus strain JLSY04 as a template,Gene fragm... [Objective] Sheep contagious ecthyma virus B2L gene recombinant adenovirus was built by adenovirus vector system.[Method] Genome DNA extracted from sheep contagious ecthyma virus strain JLSY04 as a template,Gene fragments obtained from B2L by PCR amplification;B2L gene cloning was cloned into PDNR-CMD vector,screening positive clones and plasmid CTC572-6 was obtained;CTC572-6 plasmid for homologous was recombined with the adenoviral vector.Screening positive clones and bacilli PCR,digestion and sequencing and so on were identified.[Result] After identified by enzyme digestion and gene sequencing,recombinant adenovirus vector CTC572Ade-30 of carrying sheep contagious ecthyma virus B2L gene was constructed successfully.[Conclusion] Which laid the foundation for sheep contagious ecthyma genetically engineered vaccine. 展开更多
关键词 CEV B2L gene Adenovirus vector
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Genetic algorithm tuned PI controller on PMSM simplified vector control 被引量:12
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作者 WIBOWO Wahyu Kunto JEONG Seok-kwon 《Journal of Central South University》 SCIE EI CAS 2013年第11期3042-3048,共7页
A simple control structure in servo system is occasionally needed for simple industrial application which precise and high control performance is not exessively important so that the cost production can be reduced eff... A simple control structure in servo system is occasionally needed for simple industrial application which precise and high control performance is not exessively important so that the cost production can be reduced efficiently. Simplified vector control, which has simple control structure, is utilized as the permanent magnet synchronous motor control algorithm and genetic algorithm is used to tune three PI controllers used in simplified vector control. The control performance is obtained from simulation and investigated to verify the feasibility of the algorithm to be applied in the real application. Simulation results show that the speed and torque responses of the system in both continuous time and discrete time can achieve good performances. Furthermore, simplified vector control combined with genetic algorithm has a similar perfofmance with conventional field oriented control algorithm and possible to be realized into the real simple application in the future. 展开更多
关键词 simplified vector control conventional field oriented control permanent magnet synchronous motor genetic algorithm PI controller
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Construction of Recombinant Retroviral Vector Containing HIV-1 Tat Gene and Functional Detection of Expressed Tat in Target Cells 被引量:1
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作者 卢春 钱超 +2 位作者 唐桂霞 黄丽 曾怡 《Journal of Nanjing Medical University》 2003年第6期261-269,共9页
Objective: To construct recombinant retroviral vector containing HIV-1 Tatgene and evaluate the junction of the expressed Tat in target cells. Methods: HIV-1 Tat_(101) genewas recovered from pEV plasmid by Hind Ⅲ dig... Objective: To construct recombinant retroviral vector containing HIV-1 Tatgene and evaluate the junction of the expressed Tat in target cells. Methods: HIV-1 Tat_(101) genewas recovered from pEV plasmid by Hind Ⅲ digestion and cloned into expression plasmid LZESpBMN-Z toconstruct recombinant retroviral expression plasmid named LZRS-Tat_(101). Using the method ofcalcium phosphate, the construct of LZRS-Tat_(101) was then transfected into packaging cell linesPhoenix (ΦNX) which contained env and gal genes encoding structural proteins and pol gene codingfor 3 enzymes ( reverse transcriptase, protease and integrate) essential for retroviral integrationand replication . The stable transfected cell lines was obtained using puromycin to screen for morethan 3 days. Then, immunohistochemical (IHC ) staining was carried out to detect the expressionlevel of Tat_(101) protein in both transiently and stably trancfected ΦNX, respectively. Thesupematants containing recombinant virus collected from transient and stable transfected cells wereemployed to infect 293 cells, respectively, and the expressed Tat in 293 cells was tested by Westernblot. Meantime, the supematants of infected 293 cells was further added to HL3T1 cells which wereHela cell lines containing an HIV-1-LTR/CAT reporter construct to establish a co-culture system.After co-culture for 72 hours, the protein was extracted from HL3T1 cells and used for CAT activityassay. Results: After LZRS- Tat_(101) was transfected into ΦNX, the amount of expressed Tat intransient transfection cells was significantly higher than that in stable transfection cells; Tatcould be detected not only in 293 cells but also in the supematants from 293 cells culture, and Tatin the supematants could activate HIV-1 LTR promoter in HL3T1, resulting in high 'expression of CATlocated at the downstream of LTR. Conclusion: The construct of recombinant retrovirus LZRS-Tat_(101) could express Tat protein in target cells and the expressed Tat was functionally activeand can really exhibit the ability to activate transcription. 展开更多
关键词 HIV-1 tat retroviral expression vector the ability to activatetranscription
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High Speed SRM Using Vector Control for Electric Vehicle 被引量:6
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作者 Kohei Aiso Kan Akatsu 《CES Transactions on Electrical Machines and Systems》 CSCD 2020年第1期61-68,共8页
The high speed motor is effective to realize downsizing motor in an electric vehicle(EV).Switched Reluctance Motor(SRM)is possible to the high speed drive because the rotor structure has simple and robust.However,the ... The high speed motor is effective to realize downsizing motor in an electric vehicle(EV).Switched Reluctance Motor(SRM)is possible to the high speed drive because the rotor structure has simple and robust.However,the vibration and the acoustic noise are large from the drive principle.Moreover,the conventional complicated current excitation results in the difficulty of the torque controller design.To overcome these problems,the vector control has been proposed for SRM drive.However,the vector control has not been applied to the SRM in the high speed drive.In this paper,the drive conditions such as switching frequency,bus voltage for driving the SRM in the high speed region are clarified.It is shown that the proposed SRM can be driven by the vector control in the high speed region and can realize low vibration. 展开更多
关键词 Switched reluctance motor vector control high speed drive.
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Indirect Vector Control of Linear Induction Motors Using Space Vector Pulse Width Modulation 被引量:1
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作者 Arjmand Khaliq Syed Abdul Rahman Kashif +5 位作者 Fahad Ahmad Muhammad Anwar Qaisar Shaheen Rizwan Akhtar Muhammad Arif Shah Abdelzahir Abdelmaboud 《Computers, Materials & Continua》 SCIE EI 2023年第3期6263-6287,共25页
Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.T... Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.This research aims to present a novel framework for speed and thrust force control of LIM using space vector pulse width modulation(SVPWM)inverters.The framework under consideration is developed in four stages.To begin,MATLAB Simulink was used to develop a detailed mathematical and electromechanical dynamicmodel.The research presents a modified SVPWM inverter control scheme.By tuning the proportional-integral(PI)controller with a transfer function,optimized values for the PI controller are derived.All the subsystems mentioned above are integrated to create a robust simulation of the LIM’s precise speed and thrust force control scheme.The reference speed values were chosen to evaluate the performance of the respective system,and the developed system’s response was verified using various data sets.For the low-speed range,a reference value of 10m/s is used,while a reference value of 100 m/s is used for the high-speed range.The speed output response indicates that themotor reached reference speed in amatter of seconds,as the delay time is between 8 and 10 s.The maximum amplitude of thrust achieved is less than 400N,demonstrating the controller’s capability to control a high-speed LIM with minimal thrust ripple.Due to the controlled speed range,the developed system is highly recommended for low-speed and high-speed and heavy-duty traction applications. 展开更多
关键词 Space vector pulse width modulation linear induction motor proportional-integral controller indirect vector control electromechanical dynamic modeling
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Cloning of a flower-specific expression promoter from Arabidopsis thaliana and its plant expression vector construction 被引量:1
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作者 FAN Bing-you GAO Shui-ping +1 位作者 HOU Xiao-gai SHI Guo-an 《Forestry Studies in China》 CAS 2010年第4期201-205,共5页
Given the sequence of Chs gene promoter from Arabidopsis thaliana reported in GenBank (AF248988), a pair of specific PCR primers was designed with the Primer Premier 5.0 software. PCR products of about 0.5 kb were s... Given the sequence of Chs gene promoter from Arabidopsis thaliana reported in GenBank (AF248988), a pair of specific PCR primers was designed with the Primer Premier 5.0 software. PCR products of about 0.5 kb were successfully amplified with the genome DNA of A. thaliana as a DNA template and Taq polymerase as DNA polymerase. The purified PCR products were ligated to the pMD18-T vector. The sequencing result showed that the Chs promoter from A. thaliana was 531 bp long. Sequence alignment analysis based on the DNAMAN software revealed that the sequence similarity between the cloned promoter and target promoter (AF248988) was up to 100%. Online PLACE analysis indicated that the Chs promoter contained cis-elements such as TATA-box, CAAT-box, pollen-box, G-box, ACGT-containing element, R response element, Myb recognition element and TACPyAT-box. At the same time, a plant expression vectorpAtChs::GUS which fused the Chs promoter and the marker gene GUS was successfully constructed. 展开更多
关键词 Arabidopsis thaliana PROMOTER chalcone synthase CLONING plant vector construction
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NOVEL SENSORLESS VECTOR CONTROL SYSTEM OF INDUCTION MACHINE BASED ON FLUX OBSERVER IN FIELD WEAKENING 被引量:1
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作者 邹积勇 许镇琳 孙凯 《Transactions of Tianjin University》 EI CAS 2006年第1期1-5,共5页
A speed-sensorless vector control system for induction machines (IMs)is presented, According to the vector control theory of IMs, the rotor flux is estimated based on a flux observer,and the speed is estimated throu... A speed-sensorless vector control system for induction machines (IMs)is presented, According to the vector control theory of IMs, the rotor flux is estimated based on a flux observer,and the speed is estimated through the method of q-axis rotor flux converging on zero with proportional integral regulator, A 0.75 kW,50 Hz,two-pole induction machine was used in the simulation and experimental verification, The simulation model was constructed in Matlab. A series of tests were performed in the field weakening region, for both no-load and loaded operation. The estimated speed tracks the actual speed well in the based speed region and field weakening region ( 1 per unit value to 4 per unit value). The small estimation error of residual speed is due to the existence of slip. 展开更多
关键词 induction machines (IMs) sensorless vector control flux observer speed estimation
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Experimental optical computing of complex vector convolution with twisted light 被引量:2
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作者 Ling Hong Haoxu Guo +3 位作者 Xiaodong Qiu Fei Lin Wuhong Zhang Lixiang Chen 《Advanced Photonics Nexus》 2023年第4期96-101,共6页
Orbital angular momentum(OAM),emerging as an inherently high-dimensional property of photons,has boosted information capacity in optical communications.However,the potential of OAM in optical computing remains almost ... Orbital angular momentum(OAM),emerging as an inherently high-dimensional property of photons,has boosted information capacity in optical communications.However,the potential of OAM in optical computing remains almost unexplored.Here,we present a highly efficient optical computing protocol for complex vector convolution with the superposition of high-dimensional OAM eigenmodes.We used two cascaded spatial light modulators to prepare suitable OAM superpositions to encode two complex vectors.Then,a deep-learning strategy is devised to decode the complex OAM spectrum,thus accomplishing the optical convolution task.In our experiment,we succeed in demonstrating 7-,9-,and 11-dimensional complex vector convolutions,in which an average proximity better than 95%and a mean relative error<6%are achieved.Our present scheme can be extended to incorporate other degrees of freedom for a more versatile optical computing in the high-dimensional Hilbert space. 展开更多
关键词 optical computing complex vector convolution orbital angular momentum photonic spatial modes
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Compensation of Dead-Time Effect of Speed Sensorless Vector Control System
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作者 夏超英 张靖 《Transactions of Tianjin University》 EI CAS 2011年第5期351-355,共5页
The key of speed sensorless vector control system lies in the accurate orientation of magnetic field. In some field-oriented algorithms, the integrator of observers and the dead-time effect bring in system errors duri... The key of speed sensorless vector control system lies in the accurate orientation of magnetic field. In some field-oriented algorithms, the integrator of observers and the dead-time effect bring in system errors during the estimation of field position. In this paper, a saturated feedback integrator is used, and the dead-time effect is compen- sated by current positive feedback. Experiments were carried out on the hardware platform of MCK2407, with chip TMS320LF2407 from TI Company. The results show that the prooosed method is simole and effective, and the accuracy of field position is improved. 展开更多
关键词 induction motor speed sensorless vector control DSP COMPENSATION DEAD-TIME field orientation
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Design and Development of a Vector Control System of Induction Motor Based on Dual CPU for Electric Vehicle
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作者 孙逢春 翟丽 +1 位作者 张承宁 彭连云 《Journal of Beijing Institute of Technology》 EI CAS 2003年第3期290-295,共6页
A vector control system for electric vehicle (EV) induction motor drive system is designed and developed. Its hardware system based on dual CPU(microcomputer 80C196KC and DSP TMS320F2407) is implemented. The fundament... A vector control system for electric vehicle (EV) induction motor drive system is designed and developed. Its hardware system based on dual CPU(microcomputer 80C196KC and DSP TMS320F2407) is implemented. The fundamental mathematics equations of induction motor in the general synchronously rotating reference frame ( M T frame) used for vector control are achieved by coordinate transformation. Rotor flux equation and torque equation are deduced. According to these equations, an induction motor mathematical model and rotor flux observer model are built separately. The rotor flux field oriented vector control method is implemented based on these models in system software, some of the simulation results with Matab/Simulink are given. The simulation results show that the vector control system for EV induction motor drive system has better static and dynamic performance, and the rotor flux field oriented vector control method was practically verified. 展开更多
关键词 vector control induction motor electric vehicle
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Modified sensorless vector control system of IM based on flux observer
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作者 邹积勇 许镇琳 孙凯 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第6期880-883,共4页
This paper presents a speed sensorless vector control system for induction machine (IM),which is based on a flux observer. According to vector control theory of IM,the q-axis rotor flux converging on zero is utilized ... This paper presents a speed sensorless vector control system for induction machine (IM),which is based on a flux observer. According to vector control theory of IM,the q-axis rotor flux converging on zero is utilized for speed estimation. Additionally this system solved the online identification of stator resistance by d-axis flux error. The advantages of the proposed system are simplicity and avoidance of the problems caused by only using a voltage model. The effectiveness of the proposed system has been verified by simulation and experimentation. 展开更多
关键词 induction machine sensorless vector control flux observer speed estimation
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Research on vector control system of induction motor for electric vehicle
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作者 裴泳春 陈霞 +1 位作者 苗见雨 李进香 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期397-404,共8页
In order to improve the effect of the induction motor controller of the electric vehicle and meet the special requirements of the electric vehicle,an improved method-vector control method is put forward.By analyzing t... In order to improve the effect of the induction motor controller of the electric vehicle and meet the special requirements of the electric vehicle,an improved method-vector control method is put forward.By analyzing the traditional vector control method,a model of induction motor is established considering stator iron loss and rotor iron loss.This model contains physical model and mathematical model.Mathematical model is set up based on the special requirements of electric vehicles on the induction motor,that is,the induction motor must have a wide speed range and fast torque response.Then,through the extraction of the formula,the dynamic compensation proposal and static compensation proposal can be got.Ultimately,the simulation analysis testifies the effectiveness of the method. 展开更多
关键词 eleetric vehicle induction motor vector control iron loss formatting
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Human Habitats and Malaria Vector Control in Benin: Current Situation and Implications for Effective Control
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作者 Barikissou G. Damien Armel Djènontin +1 位作者 Badirou Aguemon Franck Remoué 《Advances in Infectious Diseases》 2023年第4期706-721,共16页
Long-lasting insecticide-treated nets (LLINs) and indoor residual spraying (IRS) are the main indoor malaria vector tools control tools. The study examined housing characteristics and investigated the relationship bet... Long-lasting insecticide-treated nets (LLINs) and indoor residual spraying (IRS) are the main indoor malaria vector tools control tools. The study examined housing characteristics and investigated the relationship between the total volume of household possessions, the volume of the sleeping room, and the hanging of LLINs. A total of 831 bedrooms were randomly selected in Benin in 2015. The findings showed that mud walls were predominant in rural areas (more than 75%), while metal roofs were common (77.3% - 97.9%). Battery-powered lighting was prevalent in rural areas in Northern (97%), while open-flame oil lamps were commonly used in rural areas in Southern (86%). The availability of correct bedding was low, ranging from 1% to 10% in all households. 20% of the bedrooms had at least 50% of their volume occupied by household possessions in urban areas. In rural areas, bedrooms without LLINs had a lower mean rate ratio of the volume occupied by possessions per the total volume of the room compared to bedrooms with at least one LLIN installed (p < 0.0001). The characteristics of human habitats are not favourable to the correct use of vector control intervention indoors. It is therefore important to improve people’s living conditions as the next step for malaria elimination. 展开更多
关键词 HOUSING LIGHTING BEDDING Possessions Malaria vector control LLINs IRS
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Evaluation of Malaria Transmission and Vector Control Strategies in the Dry Season in the Cotonou V Health Zone, Benin, West Africa
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作者 Tokponnon Filémon Osse Razaki +6 位作者 Zannou Ahissou Robert Franck Alapini Marlène Sare Dabou Zoulkifilou Houessinon Festus Gounou Yerima Idayath Sominahoun André Akogbeto Martin 《Advances in Entomology》 2023年第3期156-171,共16页
The anarchic urbanization of certain African cities favors the multiplication of the malaria parasite. Thus, the urgent mobilization of African cities is essential to combat this health risk. It is, therefore, with th... The anarchic urbanization of certain African cities favors the multiplication of the malaria parasite. Thus, the urgent mobilization of African cities is essential to combat this health risk. It is, therefore, with the objective of contributing to the investigation of problem areas that the present study evaluates malaria transmission and vector control strategies in the Cotonou V health zone in particular. This is a cross-sectional study taking into account four neighborhoods, including Wologuèdè, Sainte Rita, Gbèdjromèdé and the area around Etoile Rouge. Two nocturnal captures on voluntary humans and the method of spray were carried out in the dry season from December 2021 to February 2022. On the captured Anopheles, the ELISA Circum-Sporozoite Protein test was performed to determine the infectivity and calculate some transmission parameters. Finally, we conducted a survey using the second stage sampling method with one step to ask selected households about their knowledge of vector control methods, their use and the physical integrity of LLINs. We collected 2386 culicidae of which the majority was Culex quinquefasciatus. After the ELISA test, the 29 Anopheles tested, showed no infectivity, i.e. an EIR of 0 pi/h/n. In addition, 99% of the populations in the Cotonou V area use LLINs to protect themselves. However, coils, door and window screens, aerosol sprays, skin and household repellents, and periodic indoor spraying were used. Finally, the majority of nets observed had T1 tears, but there were also T2, T3 and T4 nets (P-value = 0.0). This study confirms that malaria transmission during the dry season in the Cotonou V health zone is almost negligible but not non-existent. Also, populations are exposed to the nuisance of Culex quinquefasciatus mosquitoes continuously throughout the year. 展开更多
关键词 ANOPHELES Transmission Urban Malaria Cotonou V Health Zone vector control
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Vector Control-Development and Improvement of the Modern Chemical Insecticides
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作者 Ivan Popivanov Tanya Petkova +3 位作者 Victoria Doycheva Tzetza Doychinova Ivelin Angelov DimitarShalamanov 《Journal of Pharmacy and Pharmacology》 2015年第1期1-8,共8页
The transition from empirical and applied approach toward a scientific approach in modem medical disinsection is a result of the discoveries of the organic chemistry. The most intensive used substance in this fteld-D... The transition from empirical and applied approach toward a scientific approach in modem medical disinsection is a result of the discoveries of the organic chemistry. The most intensive used substance in this fteld-DDT (dichlorodiphenyltrichloroethane) is introduced during World War II and contributes to world practical epidemiology just as antibiotics in clinical medicine. However, after the 70s, this substance was placed under a ban, because of the accumulated evidence of many adverse health and environmental impacts globally. Improvement of the insecticides after "DDT-era" is represented by the introduction of organophosphate and carbamate insecticides in the 1960s. Their broad application is determined by better ecotoxicological characteristics. The advance in biotechnology after the 1980s establishes the new class of insecticides-synthetic pyrethroids. Nowadays they are basic for the insect control. Pyrethroids are characterized by selective impact on insects with much less impact on warm-blooded animals and the environment. Insecticides from the newest class insect growth regulators realize their mode of activity by interfering with chitin metabolism and thus prevent an insect from reaching maturity. These substances have extremely low toxicity, which makes them very promising for the treatment of civilian and military facilities. 展开更多
关键词 vector control INSECTICIDES development.
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Vector Control of Three-Phase Solar Farm Converters Based on Fictive-Axis Emulation
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作者 Kai Kang Qiaoyu Wang Jiayi Meng 《Journal of Computer Science Research》 2020年第3期10-13,共4页
In this paper,a new method for adjusting the current of three-phase voltage source DC-AC converter in orthogonal(DQ)reference frame is presented.In the DQ reference system,AC variable appears in the constant form of D... In this paper,a new method for adjusting the current of three-phase voltage source DC-AC converter in orthogonal(DQ)reference frame is presented.In the DQ reference system,AC variable appears in the constant form of DC,making the controller design the same as the DC-DC converter[1].It provides controllable gain benefits at the steady-state operating point,and finally realizes zero steady-state error[2].In addition,the creative analytical model is dedicated to building up a series of virtual quantities orthogonal to the actual single-phase system.In general,orthogonal imaginary numbers get the reference signal by delaying the real quantity by a quarter period.However,the introduction of such time delay makes the dynamic response of the system worse.In this paper,orthogonal quantities are generated from a virtual axis system parallel to the real axis,which can effectively improve the dynamic performance of traditional methods without increasing the complexity of controller structure.Through PSCAD simulation,the ideal experimental results are obtained. 展开更多
关键词 Current controller Fictive-axis Emulation(FAE) Three-phase voltage-source converters(VSCs) vector controller
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