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Adeno-associated viral vectors for modeling Parkinson's disease in non-human primates
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作者 Julia Chocarro José L.Lanciego 《Neural Regeneration Research》 2026年第1期224-232,共9页
The development of clinical candidates that modify the natural progression of sporadic Parkinson's disease and related synucleinopathies is a praiseworthy endeavor,but extremely challenging.Therapeutic candidates ... The development of clinical candidates that modify the natural progression of sporadic Parkinson's disease and related synucleinopathies is a praiseworthy endeavor,but extremely challenging.Therapeutic candidates that were successful in preclinical Parkinson's disease animal models have repeatedly failed when tested in clinical trials.While these failures have many possible explanations,it is perhaps time to recognize that the problem lies with the animal models rather than the putative candidate.In other words,the lack of adequate animal models of Parkinson's disease currently represents the main barrier to preclinical identification of potential disease-modifying therapies likely to succeed in clinical trials.However,this barrier may be overcome by the recent introduction of novel generations of viral vectors coding for different forms of alpha-synuclein species and related genes.Although still facing several limitations,these models have managed to mimic the known neuropathological hallmarks of Parkinson's disease with unprecedented accuracy,delineating a more optimistic scenario for the near future. 展开更多
关键词 adeno-associated viral vectors ALPHA-SYNUCLEIN DOPAMINE Lewy bodies NEURODEGENERATION NEUROMELANIN NEUROPATHOLOGY substantia nigra
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A novel BaEVRless-LV packaging system for the production of lentiviral vectors for clinical-grade CAR-NK cell manufacturing
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作者 Yinyin Zhang Minghuan Zhang +5 位作者 Mengyuan Li Lihong Zong Qian Ye Wen Lei Wenhai Deng Wenbin Qian 《Cancer Biology & Medicine》 2025年第2期137-143,共7页
Chimeric antigen receptor natural killer(CAR-NK)cell therapy is an alternative immunotherapy that provides robust tumor-eliminating effects without inducing life-threatening toxicities and graft-versus-host disease.CA... Chimeric antigen receptor natural killer(CAR-NK)cell therapy is an alternative immunotherapy that provides robust tumor-eliminating effects without inducing life-threatening toxicities and graft-versus-host disease.CAR-NK cell therapy has enabled the development of“off-the-shelf”products that bypass the lengthy and expensive cell manufacturing process1. 展开更多
关键词 LENTIVIRAL packaging vectors alternative immunotherapy chimeric antigen receptor natural system cell manufacturing process NOVEL
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Insecticide resistance status of malaria vectors in endemic states of India(2017-2024):A scoping review
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作者 Kamaraju Raghavendra Poonam Sharma Velamuri +1 位作者 Vartika Singhal Roop Kumari 《Asian Pacific Journal of Tropical Medicine》 2025年第8期337-352,I0003-I0013,共27页
Objective:To collate and summarize phenotypic insecticide susceptibility data of Indian malaria vectors from 2017 to 2024,focusing on insecticides used in adult vector control,dichloro diphenyl trichloroethane,malathi... Objective:To collate and summarize phenotypic insecticide susceptibility data of Indian malaria vectors from 2017 to 2024,focusing on insecticides used in adult vector control,dichloro diphenyl trichloroethane,malathion,deltamethrin,alpha-cypermethrin,and permethrin to identify resistance patterns to different classes of insecticides.Methods:The data included information on vector species,location of the study(state/district),insecticide tested,mortality percentage,and susceptibility classification based on the World Health Organization interpretation criteria.Retrospective data were collected from peer-reviewed publications(2017-2024)and up to June 2025.The data were collated for five major malaria vector species,namely Anopheles(An.)culicifacies,An.fluviatilis,An.stephensi,An.baimaii,and An.minimus.Results:Insecticide susceptibility data were available from 86 districts across 16 Indian states for 40615 mosquitoes.The majority of the data was on An.culicifacies(n=28308),followed by An.stephensi(n=5611),An.fluviatilis(n=5967),An.baimaii(n=365),and An.minimus(n=364).Intensity bioassays revealed low to moderate resistance levels in An.culicifacies populations from selected districts in 3 states,Odisha,Madhya Pradesh,and Chhattisgarh against deltamethrin and alpha-cypermethrin.Conclusions:This review highlights spatial and species-level variations in insecticide susceptibility among Indian malaria vectors.The low to moderate intensity suggested that it may not yet be severe enough to cause operational failure with current vector control interventions.Continued monitoring of insecticide resistance,as well as the use of new-generation insecticides and interventions,is suggested to sustain vector control efficacy and manage insecticide resistance in malaria vectors to support India’s malaria elimination. 展开更多
关键词 Malaria vectors Insecticide resistance INDIA
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Comprehensive Evaluation on Atmospheric Motion Vectors from Fengyun-4B Geostationary Satellite and Their Application in the South China Sea Monsoon Onset
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作者 PAN Qiao-ying WANG Gang +3 位作者 ZHOU Run-dong MIN Min ZHANG Xiao-hu MOU Xiao-xuan 《Journal of Tropical Meteorology》 2025年第6期647-660,共14页
Although the Chinese new-generation Fengyun-4B(FY-4B) geostationary satellite Atmospheric Motion Vector(AMV) products became operational in June 2022, their accuracy and utility remain largely unexamined. This study c... Although the Chinese new-generation Fengyun-4B(FY-4B) geostationary satellite Atmospheric Motion Vector(AMV) products became operational in June 2022, their accuracy and utility remain largely unexamined. This study comprehensively evaluates FY-4B AMV products for August and October 2023, as well as January and April 2024,exploring their application in monitoring the South China Sea Summer Monsoon(SCSSM) onset. The results indicate that AMV products derived from the upper-level water vapor absorption channel(AMV_WV) and the infrared channel(AMV_IR) demonstrate high accuracy when compared with ERA5 reanalysis data. The root mean square error(RMSE) is mostly between 4.5 m s^(–1)and 6.4 m s^(–1), with coefficients of determination(R2) values ranging from 0.7 to 0.8, indicating the overall reliability of FY-4B AMVs. The observation errors of AMVs exhibit significant vertical structure characteristics. Specifically, the AMV_WV products demonstrate superior accuracy above 350 h Pa, while the AMV_IR products exhibit reduced errors in the layers between 200–500 h Pa and 700–950 h Pa. Spatially, most areas exhibit low observation errors for AMVs, while clear-sky weather and deep convective cloud systems can increase errors. A lack of clouds or water vapor may reduce the number of observation samples in some areas, leading to unstable RMSE performance, which is particularly evident for AMV_WV RMSE around 25°–30°N in January and near 25°S in August. Deep convective cloud systems can influence AMV retrieval results, leading to systematic observation errors, especially for the infrared channel.Additionally, AMV_WV is more reliable during the daytime, with a lower RMSE compared to nighttime, while AMV_IR exhibits a diverging diurnal variation pattern. Finally, the FY-4B AMV_WV products were applied to monitor the SCSSM event in 2024. Significant zonal wind direction reversal characteristics were observed in key regions around the onset date,indicating that AMVs can serve as effective indicators for monitoring the SCSSM onset. 展开更多
关键词 atmospheric motion vectors Fengyun-4B geostationary satellite the South China Sea monsoon onset
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The Varieties of Semi-Conformal Vectors of Rank-One Even Lattice Vertex Operator Algebras
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作者 CHU Yan-jun GAO Yi-bo 《Chinese Quarterly Journal of Mathematics》 2025年第1期36-48,共13页
In this paper,we shall study structures of even lattice vertex operator algebras by using the geometry of the varieties of their semi-conformal vectors.We first give the varieties of semi-conformal vectors of a family... In this paper,we shall study structures of even lattice vertex operator algebras by using the geometry of the varieties of their semi-conformal vectors.We first give the varieties of semi-conformal vectors of a family of vertex operator algebras V_(√kA_(1)) associated to rank-one positive definite even lattices √kA_(1) for arbitrary positive integers k to characterize these even lattice vertex operator algebras.In such a family of lattice vertex operator algebras V_(√kA_(1)),the vertex operator algebra V_(√2A_(1)) is different from others.Hence we describe the varieties of semi-conformal vectors of V_(√2A_(1)) and the fixed vertex operator subalgebra V^(+)√2A_(1).Moreover,as applications,we study the relations between vertex operator algebras V_(√kA_(1) )and L_(sl_(2))(k,0)for arbitrary positive integers k by the viewpoint of semi-conformal homomorphisms of vertex operator algebras.For case k=2,in the series of rational simple affine vertex operator algebras L_(sl_(2))(k,0)for positive integers k,we show that L_(sl_(2))(2,0)is a unique frame vertex operator algebra with rank 3. 展开更多
关键词 Vertex operator algebra Semi-conformal vector Affine variety
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Stem cell therapy for intervertebral disc degeneration:Clinical progress with exosomes and gene vectors
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作者 Zhi-Peng Li Han Li +13 位作者 Yu-Hua Ruan Peng Wang Meng-Ting Zhu Wei-Ping Fu Rui-Bo Wang Xiao-Dong Tang Qi Zhang Sen-Li Li He Yin Cheng-Jin Li Yi-Gong Tian Rui-Ning Han Yao-Bin Wang Chang-Jiang Zhang 《World Journal of Stem Cells》 2025年第4期20-35,共16页
Intervertebral disc degeneration is a leading cause of lower back pain and is characterized by pathological processes such as nucleus pulposus cell apoptosis,extracellular matrix imbalance,and annulus fibrosus rupture... Intervertebral disc degeneration is a leading cause of lower back pain and is characterized by pathological processes such as nucleus pulposus cell apoptosis,extracellular matrix imbalance,and annulus fibrosus rupture.These pathological changes result in disc height loss and functional decline,potentially leading to disc herniation.This comprehensive review aimed to address the current challenges in intervertebral disc degeneration treatment by evaluating the regenerative potential of stem cell-based therapies,with a particular focus on emerging technologies such as exosomes and gene vector systems.Through mechanisms such as differentiation,paracrine effects,and immunomodulation,stem cells facilitate extracellular matrix repair and reduce nucleus pulposus cell apoptosis.Despite recent advancements,clinical applications are hindered by challenges such as hypoxic disc environments and immune rejection.By analyzing recent preclinical and clinical findings,this review provided insights into optimizing stem cell therapy to overcome these obstacles and highlighted future directions in the field. 展开更多
关键词 EXOSOMES Extracellular matrix repair Gene vector system Hypoxic environment Intervertebral disc degeneration Mesenchymal stem cells Regenerative medicine Stem cell therapy
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Energy-efficient MPCC Using Centroid-synthesized Virtual Voltage Vectors for IM Drives in Electric Vehicles
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作者 Rinki Roy Chowdhury G Koperundevi 《CES Transactions on Electrical Machines and Systems》 2025年第3期352-362,共11页
This paper presents an improved,energy-efficient Model Predictive Current Control(MPCC)strategy based on centroid-based virtual voltage vector synthesis for three-phase inverter-fed induction motor drives in electric ... This paper presents an improved,energy-efficient Model Predictive Current Control(MPCC)strategy based on centroid-based virtual voltage vector synthesis for three-phase inverter-fed induction motor drives in electric vehicle(EV)applications.Unlike conventional finite-set MPCC methods that rely on cost function evaluation over discrete switching states,the proposed approach eliminates the need for look-up tables by employing a pre-defined set of virtual vectors.These centroid-based virtual voltage vectors are synthesized by combining two adjacent active vectors and two nonzero voltage vectors in opposite directions adjacent to the sector replacing the traditional switching set.They approximate the reference voltage vector in both magnitude and phase angle,thereby reducing current tracking error through a simplified cost function.The number of candidate vectors is reduced,preserving computational efficiency.Furthermore,the scheme ensures zero average common-mode voltage(CMV)per sampling interval by completely avoiding zero-voltage vectors(ZVVs).The proposed method reduces torque ripple by up to 17%compared to the conventional approach and lowers stator current total harmonic distortion(THD)by 37%,while ensuring evenly distributed switching transitions among inverter legs.This results in reduced switching losses and enhanced drive efficiency-particularly advantageous in EV applications.Experimental validation under the high-speed extra urban driving cycle(EUDC)and low-speed ECE-R15 cycle,including torque ripple and energy consumption analysis,confirms the effectiveness of the approach,achieving an overall efficiency of 83.3%. 展开更多
关键词 Common mode voltage(CMV) Induction motor(IM) Total harmonic distortions(THD) Zero-voltage vector(ZVV)
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A Preliminary Analysis on the Construction and Expression of Eukaryotic Expression Vectors of Mytilin and Myticin from Mytilus coruscus 被引量:10
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作者 武梅 范美华 +2 位作者 廖智 石戈 王日昕 《Agricultural Science & Technology》 CAS 2010年第7期72-75,共4页
[Objective] The aim was to study the construction and expression of eukaryotic expression vectors of antibacterial peptides (mytilin and myticin) from Mytilus coruscus.[Method] By the screening of antibacterial pept... [Objective] The aim was to study the construction and expression of eukaryotic expression vectors of antibacterial peptides (mytilin and myticin) from Mytilus coruscus.[Method] By the screening of antibacterial peptide genes of mytilin and myticin of Mytilus coruscus,five antibacterial peptide genes were selected.Then,the relative eukaryotic expressing vectors were constructed by the use of PCR technique and DNA recombinant technology.Subsequently,they were transferred in to S78 Saccharomyces cerevisia by using LiAC transformation method,and then preliminary expressing analysis was carried out.[Result] Five eukaryotic expressing vectors of antibacterial peptides from Mytilus coruscus were successfully constructed,and the results of mRNA detection revealed that the five antibacterial peptides from Mytilus coruscus were successfully transcribed.[Conclusion] The results provide a basis for using genetic engineering to express antibacterial peptides of mytilin and myticin from Mytilus coruscus,and for developing the further study of antibacterial peptides from Mytilus coruscus based on this. 展开更多
关键词 Mytilus coruscus Antibiotic peptide Mytilin Myticin Expression vector
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利用i-vectors构建区分性话者模型的话者确认 被引量:3
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作者 方昕 李辉 刘青松 《小型微型计算机系统》 CSCD 北大核心 2014年第3期685-688,共4页
对于电话手机语音的文本无关话者确认,运用联合因子分析构建话者信息子空间与信道信息子空间来进行失配信道补偿取得了较好的效果.然而研究表明,信道信息子空间仍然包含了可以用来区分话者的信息.因此,本文运用一种既包含话者信息又包... 对于电话手机语音的文本无关话者确认,运用联合因子分析构建话者信息子空间与信道信息子空间来进行失配信道补偿取得了较好的效果.然而研究表明,信道信息子空间仍然包含了可以用来区分话者的信息.因此,本文运用一种既包含话者信息又包含信道信息的全变量信息子空间来提取i-vectors低维特征矢量,再运用类内协方差规整进行失配信道补偿,最后用补偿后的i-vectors特征矢量构建支持向量机话者模型.在NIST08数据库上实验表明,本文所构建系统的性能在等误识率和最小检测代价函数上有相对近70%的提高. 展开更多
关键词 话者确认 全变量信息子空间 类内协方差规整 支持向量机 i—vectors
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Cloning of Cotton Delta-12 Oleate Desaturase Gene FAD2-1 and Construction of Its ihpRNA and amiRNA Interference Vectors 被引量:1
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作者 赵立群 李红岺 +3 位作者 李仁 李蔚 华金平 郭仰东 《Agricultural Science & Technology》 CAS 2012年第11期2281-2283,2286,共4页
Delta-12 oleate desaturase gene (FAD2-1) which converts oleic acid into linoleic acid, is the key enzyme determining the fatty acid composition of cottonseed oil. By employing RT-PCR method, full length cDNA of cott... Delta-12 oleate desaturase gene (FAD2-1) which converts oleic acid into linoleic acid, is the key enzyme determining the fatty acid composition of cottonseed oil. By employing RT-PCR method, full length cDNA of cotton delta-12 oleate desat- urase gene GhFAD2-1 containing an open reading frame of 1 158 bp was cloned for constructing RNAi vector. A 515 bp long specific fragment of this gene was se- lected for constructing ihpRNA vector under the control of a seed-specific promoter NAPIN, named pFGC1008-NAPIN-FAD2-1; meanwhile miRNA gene-silencing vector pCAMBIA1302-amiRNA-FAD2-1 targeting GhFAD2-1 was also constructed. 展开更多
关键词 Cotton delta-12 oleate desaturase gene GhFAD2-1 ihpRNA interferencevector amiRNA interference vector High oleic acid contents
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Construction of Prokaryotic Expression Vectors of EBP1 Gene from Nervilia Fordii (Hance) Schltr. 被引量:1
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作者 黄琼林 何瑞 +1 位作者 詹若挺 陈蔚文 《Agricultural Science & Technology》 CAS 2012年第6期1211-1214,共4页
[Objective] To construct prokaryotic expression vectors encoding gene Erb3binding protein (EBP1), which plays important roles in regulating plant organ size from Nervilia fordii (Hance) Schltr. [Methods] PCR produ... [Objective] To construct prokaryotic expression vectors encoding gene Erb3binding protein (EBP1), which plays important roles in regulating plant organ size from Nervilia fordii (Hance) Schltr. [Methods] PCR products of NfEBP1 with particular restriction sites and expression vectors, pET-28 and pET-16b were digested. Ligation, transformation and selection were performed to construct the recombinant plasmids pET-28-NfEBP1 and pET-16-NfEBP1. The recombinant plasmids were transformed into E. coli BL21 using heat -shock transformation. [Results] Recombinant plasmids pET-28-NfEBP1-1188 and pET-16-NfEBP1-1188 were constructed and transformed into expressional host cells, E. coli BL21, and validated by colony PCR, sequencing and double digestion. [Conclusion] Prokaryotic expression vectors of EBP1 gene from N. fordii were successfully constructed, which laid the foundation for characterization of the gene function. 展开更多
关键词 Nervilia fordii (Hance) Schltr. Coding gene of Erb3-binding protein (EBP1) Prokaryotic expression vector
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Improving endothelial dysfunction:An important mechanism of traditional Chinese medicine in reducing the occurrence of severe dengue
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作者 Jiao Tang Si-Qi Li +3 位作者 Yuan-Yuan Chen De-Hong Ma Wei-Bo Wen Huan-Tian Cui 《Infectious Diseases Research》 2026年第1期10-12,共3页
Dengue fever is an acute infectious disease caused by the dengue virus and transmitted by mosquito vectors[1].Its clinical manifestations include high fever,headache,muscle and joint pain,and rash.It holds a significa... Dengue fever is an acute infectious disease caused by the dengue virus and transmitted by mosquito vectors[1].Its clinical manifestations include high fever,headache,muscle and joint pain,and rash.It holds a significant position in global public health.In recent years,its incidence has continued to rise worldwide[2],making it one of the major diseases threatening human health.The disease course of dengue fever is divided into three typical phases:the acute febrile phase,the critical phase,and the recovery phase.While most patients experience mild symptoms,some may progress to severe dengue and potentially fatal outcomes if not promptly and effectively treated during the critical phase. 展开更多
关键词 mosquito vectors its dengue fever dengue virus acute infectious disease severe dengue acute febrile endothelial dysfunction traditional chinese medicine
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Simulations of Using Vectors in Natural Sciences Education
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作者 Dijana Capeska Bogatinoska Linda Fahlberg Stojanovska Biljana Janakievska 《Computer Technology and Application》 2013年第9期455-459,共5页
The implementation of ICT (information and communication technologies) into the educational process is becoming a reality in the 21st century. Today's students grow up with technology. To keep their attention, scie... The implementation of ICT (information and communication technologies) into the educational process is becoming a reality in the 21st century. Today's students grow up with technology. To keep their attention, scientific problems should be solved through visualization, which is made possible using ICT in the educational process. In the modem educational process, students still have difficulties in learning science concepts. Also, it is a very common problem that students cannot apply mathematical language and concepts into other science areas such as physics, engineering, etc. For example, students start learning about vectors in mathematics in secondary school. Vectors are very important because they have a wide area of applications especially in physics, engineering and navigation to represent forces, tension, velocity, etc.. Using the free mathematical software GeoGebra, a simulation of using vectors in these areas is made. It will be shown that such simulations increase students' interest, keep their attention, and make this knowledge more real and more understandable and connected to the physical world and thus more applicable to their other studies. 展开更多
关键词 EDUCATION GeoGebra ICT vectors.
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A Convolutional Neural Network-Based Deep Support Vector Machine for Parkinson’s Disease Detection with Small-Scale and Imbalanced Datasets
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作者 Kwok Tai Chui Varsha Arya +2 位作者 Brij B.Gupta Miguel Torres-Ruiz Razaz Waheeb Attar 《Computers, Materials & Continua》 2026年第1期1410-1432,共23页
Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using d... Parkinson’s disease(PD)is a debilitating neurological disorder affecting over 10 million people worldwide.PD classification models using voice signals as input are common in the literature.It is believed that using deep learning algorithms further enhances performance;nevertheless,it is challenging due to the nature of small-scale and imbalanced PD datasets.This paper proposed a convolutional neural network-based deep support vector machine(CNN-DSVM)to automate the feature extraction process using CNN and extend the conventional SVM to a DSVM for better classification performance in small-scale PD datasets.A customized kernel function reduces the impact of biased classification towards the majority class(healthy candidates in our consideration).An improved generative adversarial network(IGAN)was designed to generate additional training data to enhance the model’s performance.For performance evaluation,the proposed algorithm achieves a sensitivity of 97.6%and a specificity of 97.3%.The performance comparison is evaluated from five perspectives,including comparisons with different data generation algorithms,feature extraction techniques,kernel functions,and existing works.Results reveal the effectiveness of the IGAN algorithm,which improves the sensitivity and specificity by 4.05%–4.72%and 4.96%–5.86%,respectively;and the effectiveness of the CNN-DSVM algorithm,which improves the sensitivity by 1.24%–57.4%and specificity by 1.04%–163%and reduces biased detection towards the majority class.The ablation experiments confirm the effectiveness of individual components.Two future research directions have also been suggested. 展开更多
关键词 Convolutional neural network data generation deep support vector machine feature extraction generative artificial intelligence imbalanced dataset medical diagnosis Parkinson’s disease small-scale dataset
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Exploration of larvicidal and adult emergence inhibition activities of Ricinus communis seed extract against three potential mosquito vectors in Kolkata,India 被引量:9
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作者 Shyamapada Mandal 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第8期605-609,共5页
Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectors Anopheles stephensi(An. slephensi),Culex quinquefa... Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectors Anopheles stephensi(An. slephensi),Culex quinquefasciatus(Cx.quinquefasciatus) and Aedes albopictus(Ae.albopictus) in India.Methods:The R.communis seed extract was tested,employing WHO procedure,against fourth larval instars of the three mosquito species for 24 h and larval mortalities were recorded at various concentrations(2-64μg/mL):the 24 h LC<sub>50</sub> values of the R.communis seed extract were determined following Probit analysis.The larval killing,antipupation and adult emergence inhibition rates of the test extract,using a single concentration of 2μLC<sub>50</sub>,were studied at different time periods(24-72 h):the extract toxicity was tested against a fish.Oreochromis niloticus(O.niloticus).Results:The R.communis seed extract exhibited larvicidal effects with 100%killing activities at concentrations 32-64μg/mL,and with LC<sub>50</sub> values 7.10.11.64 and 16.84μg/mL for Cx.quinquefasciatus,An.stephensi and Ae.albopictus larvae,respectively. When the larvae were treated with the extract at a single concentration of 2×LC<sub>50</sub>,significant differences were observed,compared to control groups,in rate of pupation(P【0.001) as well as in adult formation(P【0.001).Conclusions:The present findings suggest that the R.communis seed extract provided an excellent potential for controlling An.stephensi,Cx.quinquefasciatus and Ae. albopictus mosquito vectors. 展开更多
关键词 RICINUS communis MOSQUITO vectors LARVICIDAL activity PROBIT analysis Adult emergence INHIBITION
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A Composite Approach of Radar Echo Extrapolation Based on TREC Vectors in Combination with Model-Predicted Winds 被引量:18
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作者 梁巧倩 冯业荣 +4 位作者 邓文剑 胡胜 黄燕燕 曾沁 陈子通 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第5期1119-1130,共12页
Extending the lead time of precipitation nowcasts is vital to improvements in heavy rainfall warning, flood mitigation, and water resource management. Because the TREC vector (tracking radar echo by correlation) rep... Extending the lead time of precipitation nowcasts is vital to improvements in heavy rainfall warning, flood mitigation, and water resource management. Because the TREC vector (tracking radar echo by correlation) represents only the instantaneous trend of precipitation echo motion, the approach using derived echo motion vectors to extrapolate radar reflectivity as a rainfall forecast is not satisfactory if the lead time is beyond 30 minutes. For longer lead times, the effect of ambient winds on echo movement should be considered. In this paper, an extrapolation algorithm that extends forecast lead times up to 3 hours was developed to blend TREC vectors with model-predicted winds. The TREC vectors were derived from radar reflectivity patterns in 3 km height CAPPI (constant altitude plan position indicator) mosaics through a cross-correlation technique. The background steering winds were provided by predictions of the rapid update assimilation model CHAF (cycle of hourly assimilation and forecast). A similarity index was designed to determine the vertical level at which model winds were applied in the extrapolation process, which occurs via a comparison between model winds and radar vectors. Based on a summer rainfall case study, it is found that the new algorithm provides a better forecast. 展开更多
关键词 radar motion vector rapid update assimilation model extrapolation nowcast
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Targeting lentiviral vectors to primordial germ cells(PGCs):An efficient strategy for generating transgenic chickens 被引量:5
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作者 Zi-Qin Jiang Han-Yu Wu +2 位作者 Jing Tian Ning Li Xiao-Xiang Hu 《Zoological Research》 SCIE CAS CSCD 2020年第3期281-291,共11页
Recent advances in avian transgenic studies highlight the possibility of utilizing lentiviral vectors as tools to generate transgenic chickens. However, low rates of gonadal chimerism and germ line transmission effici... Recent advances in avian transgenic studies highlight the possibility of utilizing lentiviral vectors as tools to generate transgenic chickens. However, low rates of gonadal chimerism and germ line transmission efficiency still limit the broad usage of this method in creating transgenic chickens. In this study, we implemented a simple strategy using modified lentiviral vectors targeted to chicken primordial germ cells(PGCs) to generate transgenic chickens. The lentiviral vectors were pseudotyped with a modified Sindbis virus envelope protein(termed M168) and conjugated with an antibody specific to PGC membrane proteins. We demonstrated that these optimized M168-pseudotyped lentiviral vectors conjugated with SSEA4 antibodies successfully targeted transduction of PGCs in vitro and in vivo. Compared with the control, 50.0%–66.7% of chicken embryos expressed green fluorescent protein(GFP) in gonads transduced by the M168-pseudotyped lentivirus. This improved the targeted transduction efficiency by 30.0%–46.7%. Efficient chimerism of exogenous genes was also observed. This targeting technology could improve the efficiency of germ line transmission and provide greater opportunities for transgenic poultry studies. 展开更多
关键词 M168-pseudotyped lentiviral vectors Primordial germ cells Targeted transduction Transgenic chickens SSEA4
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Recent advances in liver-directed gene transfer vectors 被引量:8
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作者 Dong Xia, Ming-Man Zhang and Lu-Nan Yan Department of General Surgery, West China Hospi-tal, Sichuan University, Chengdu 610041 , China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2004年第3期332-336,共5页
BACKGROUND: Gene therapy as part of modern molecu-lar medicine holds great promise for the treatment of hepa-tocellular carcinoma (HCC) and has the potential to bringa revolutionary era to cancer treatment. For the pa... BACKGROUND: Gene therapy as part of modern molecu-lar medicine holds great promise for the treatment of hepa-tocellular carcinoma (HCC) and has the potential to bringa revolutionary era to cancer treatment. For the past de-cade various viral and non-viral vectors have been engi-neered for improved liver gene therapy.DATA RESOURCES: An English-language literature searchusing MEDLINE (2004), Index Medicus (2004) and biblio-graphic reviews of books and review articles. Liver-directedgene transfer vectors and their history and recent clinicalapplications.RESULTS: The ultimate goal of liver-directed gene therapyfor HCC is the stable expression of a therapeutic transgenein a significant proportion of hepatocytes. The design of avector system providing efficient and stable gene engraft-ment and expression in human hepatocytes is still a chal-lenging issue. The advantages and disadvantages of the ge-netically engineered vector of viral or non-viral origin arediscussed with respect to their essential relevance.CONCLUSION: Liver gene therapy has a long way to goand efficient and innocuous liver-directed gene transfer vec-tors are therefore urgently required. 展开更多
关键词 hepatocellular carcinoma gene therapy VECTOR
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In situ tumor vaccination with adenovirus vectors encoding measles virus fusogenic membrane proteins and cytokines 被引量:4
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作者 Dennis Hoffmann Wibke Bayer Oliver Wildner 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第22期3063-3070,共8页
AIM: To evaluate whether intratumoral expression of measles virus fusogenic membrane glycoproteins H and F (MV-FMG), encoded by an adenovirus vector Ad.MV-HI F, alone or in combination with local coexpression of cy... AIM: To evaluate whether intratumoral expression of measles virus fusogenic membrane glycoproteins H and F (MV-FMG), encoded by an adenovirus vector Ad.MV-HI F, alone or in combination with local coexpression of cytokines (IL-2, IL-12, IL-18, IL-21 or GM-CSF), can serve as a platform for inducing tumor-specific immune responses in colon cancer.METHODS: We used confocal laser scanning microscopy and flow cytometry to analyze cell-cell fusion after expression of MV-FMG by dye colocalization. In a syngeneic bilateral subcutaneous MC38 and Colon26 colon cancer model in C57BL/6 and BALB/c mice, we assessed the effect on both the directly vector-treated tumor as well as the contralateral, not directly vector- treated tumor. We assessed the induction of a tumorspecific cytotoxic T lymphocyte (CTL) response with a lactate dehydrogenase (LDH) release assay.RESULTS: We demonstrated in vitro that transduction of MC38 and Colon26 cells with Ad.MV-H/F resulted in dye colocalization, indicative of cell-cell fusion, in addition, in the syngeneic bilateral tumor model we demonstrated a significant regression of the directly vector-inoculated tumor upon intratumoral expression of MV-FMG alone or in combination with the tested cytokines. We observed the highest anti-neoplastic efficacy with MV-FMG and lL-21 coexpression. The degree of tumor regression of the not directly vector-treated tumor correlated with the anti-neoplastic response of the directly vector-treated tumor. This regression was mediated by a tumor-specific CTL response.CONCLUSION: Our data indicate that intratumoral expression of measles virus fusogenic membrane glycoproteins is a promising tool both for direct tumor treatment as well as for tumor vaccination approaches that can be further enhanced by cytokine coexpression. 展开更多
关键词 Adenovirus vectors Measles virus fusogenic membrane glycoproteins Colorectal cancer INTERLEUKINS
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Multi-camera calibration method based on minimizing the difference of reprojection error vectors 被引量:6
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作者 HUO Ju LI Yunhui YANG Ming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期844-853,共10页
In order to achieve a high precision in three-dimensional(3D) multi-camera measurement system, an efficient multi-cameracalibration method is proposed. A stitching method of large scalecalibration targets is deduced... In order to achieve a high precision in three-dimensional(3D) multi-camera measurement system, an efficient multi-cameracalibration method is proposed. A stitching method of large scalecalibration targets is deduced, and a fundamental of multi-cameracalibration based on the large scale calibration target is provided.To avoid the shortcomings of the method, the vector differencesof reprojection error with the presence of the constraint conditionof the constant rigid body transformation is modelled, and mini-mized by the Levenberg-Marquardt (LM) method. Results of thesimulation and observation data calibration experiment show thatthe accuracy of the system calibrated by the proposed methodreaches 2 mm when measuring distance section of 20 000 mmand scale section of 7 000 mm × 7 000 mm. Consequently, theproposed method of multi-camera calibration performs better thanthe fundamental in stability. This technique offers a more uniformerror distribution for measuring large scale space. 展开更多
关键词 vision measurement multi-camera calibration field stitching vector error
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