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Whole Perfect Vectors and Fermat’s Last Theorem
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第1期34-42,共9页
A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm de... A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm definition, and some vector-specific structures. 展开更多
关键词 Fermat’s Last Theorem Whole Perfect vectors Sine and Cosine Functions Natural and Rational vectors Fermat vectors
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Research on Node Classification Based on Joint Weighted Node Vectors
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作者 Li Dai 《Journal of Applied Mathematics and Physics》 2024年第1期210-225,共16页
Node of network has lots of information, such as topology, text and label information. Therefore, node classification is an open issue. Recently, one vector of node is directly connected at the end of another vector. ... Node of network has lots of information, such as topology, text and label information. Therefore, node classification is an open issue. Recently, one vector of node is directly connected at the end of another vector. However, this method actually obtains the performance by extending dimensions and considering that the text and structural information are one-to-one, which is obviously unreasonable. Regarding this issue, a method by weighting vectors is proposed in this paper. Three methods, negative logarithm, modulus and sigmoid function are used to weight-trained vectors, then recombine the weighted vectors and put them into the SVM classifier for evaluation output. By comparing three different weighting methods, the results showed that using negative logarithm weighting achieved better results than the other two using modulus and sigmoid function weighting, and was superior to directly concatenating vectors in the same dimension. 展开更多
关键词 Node Classification Network Embedding Representation Learning Weighted vectors Training
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Photovoltaic Models Parameters Estimation Based on Weighted Mean of Vectors
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作者 Mohamed Elnagi Salah Kamel +1 位作者 Abdelhady Ramadan Mohamed F.Elnaggar 《Computers, Materials & Continua》 SCIE EI 2023年第3期5229-5250,共22页
Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy source.This is evident in the advancement of scientific research aimed at improving solar cell performance.Due to the ... Renewable energy sources are gaining popularity,particularly photovoltaic energy as a clean energy source.This is evident in the advancement of scientific research aimed at improving solar cell performance.Due to the non-linear nature of the photovoltaic cell,modeling solar cells and extracting their parameters is one of the most important challenges in this discipline.As a result,the use of optimization algorithms to solve this problem is expanding and evolving at a rapid rate.In this paper,a weIghted meaN oF vectOrs algorithm(INFO)that calculates the weighted mean for a set of vectors in the search space has been applied to estimate the parameters of solar cells in an efficient and precise way.In each generation,the INFO utilizes three operations to update the vectors’locations:updating rules,vector merging,and local search.The INFO is applied to estimate the parameters of static models such as single and double diodes,as well as dynamic models such as integral and fractional models.The outcomes of all applications are examined and compared to several recent algorithms.As well as the results are evaluated through statistical analysis.The results analyzed supported the proposed algorithm’s efficiency,accuracy,and durability when compared to recent optimization algorithms. 展开更多
关键词 Photovoltaic(PV)modules weIghted meaN oF vectors algorithm(INFO) renewable energy static PV models dynamic PV models solar energy
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Some Results for Exact Support Recovery of Block Joint Sparse Matrix via Block Multiple Measurement Vectors Algorithm
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作者 Yingna Pan Pingping Zhang 《Journal of Applied Mathematics and Physics》 2023年第4期1098-1112,共15页
Block multiple measurement vectors (BMMV) is a reconstruction algorithm that can be used to recover the support of block K-joint sparse matrix X from Y = ΨX + V. In this paper, we propose a sufficient condition for a... Block multiple measurement vectors (BMMV) is a reconstruction algorithm that can be used to recover the support of block K-joint sparse matrix X from Y = ΨX + V. In this paper, we propose a sufficient condition for accurate support recovery of the block K-joint sparse matrix via the BMMV algorithm in the noisy case. Furthermore, we show the optimality of the condition we proposed in the absence of noise when the problem reduces to single measurement vector case. 展开更多
关键词 Support Recovery Compressed Sensing Block Multiple Measurement vectors Algorithm Block Restricted Isometry Property
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On the Expression of Composite Natural Numbers as Tensorial Products of Prime Natural Powers Vectors
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作者 Debraj Nath Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2023年第6期1728-1736,共9页
This study describes how one can construct sets of composite natural numbers as tensorial products of the vectors created with the natural powers of prime numbers.
关键词 Composite Natural Numbers Prime Numbers Prime Numbers Powers vectors of Prime Numbers Powers Tensors Holding the Composite Natural Numbers
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Norms of Dual Complex Vectors and Dual Complex Matrices
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作者 Xin-He Miao Zheng-Hai Huang 《Communications on Applied Mathematics and Computation》 EI 2023年第4期1484-1508,共25页
In this paper,we investigate some properties of dual complex numbers,dual complex vectors,and dual complex matrices.First,based on the magnitude of the dual complex number,we study the Young inequality,the Hölder... In this paper,we investigate some properties of dual complex numbers,dual complex vectors,and dual complex matrices.First,based on the magnitude of the dual complex number,we study the Young inequality,the Hölder inequality,and the Minkowski inequality in the setting of dual complex numbers.Second,we define the p-norm of a dual complex vector,which is a nonnegative dual number,and show some related properties.Third,we study the properties of eigenvalues of unitary matrices and unitary triangulation of arbitrary dual complex matrices.In particular,we introduce the operator norm of dual complex matrices induced by the p-norm of dual complex vectors,and give expressions of three important operator norms of dual complex matrices. 展开更多
关键词 Dual complex number Dual complex vector Dual complex matrix p-norm Operator norm
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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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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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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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DNA immune responses induced by codelivery of IL-12 expression vectors with hepatitis C structural antigens 被引量:3
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作者 Mei-Mei Shan Ke-Zhou Liu +1 位作者 Hai-Lin Fang Zhi Chen the Institute of Infections Diseases, Zhejiang Univiersity School of Medicine, Hangzhou 310006, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2002年第4期553-557,共5页
Objective: To demonstrate the utility of DNA vaccines for the tailored methods, the efficacy of enhanced immune responses, and the types of increased im- mune responses. Methods: Four recombinant plasmids constructed ... Objective: To demonstrate the utility of DNA vaccines for the tailored methods, the efficacy of enhanced immune responses, and the types of increased im- mune responses. Methods: Four recombinant plasmids constructed in- cluded the coding regions for the core protein (pC) and for the core, E_1 and E_2 together (pCE_1E_2), IL- 12 p35 and p40. These plasmids were transfected into mammalian cells to test their protein expression and were injected into the quadriceps muscles of BALB/ C mice for measurement of specific antibodies and cytotoxic T-lymphocyte (CTL) responses. Results: All the recombinant plasmids were shown to express specific antigens stably in mammalian cells. Codelivery of pIL-12 expression cassettes with pC and pCE_1E_2 in mice resulted in the enhancement of Ag-dependent CTL responses and the reduction of specific Ab response. The CTL activity was: pC= 18.65%±5.71%, pCE_1E_2=20.07%±11.11%, pC +pIL-12=60.11%±17.37%, pCE_1E_2+pIL-12= 67.48%±15.57%, respectively. The average A val- ues of anti-HCV were pC=0.415±0.127, pCE_1E_2= 0.358±0.096, pC+pIL-12=0.210±0.086, pCE_1E_2 +pIL-12=0.258±0.125. Conclusion: Codelivery of pIL-12 with plasmid DNA can enhance the efficacy of immune responses and shift the type of immune responses. 展开更多
关键词 hepatitis C virus DNA immunization IL-12 expression vectors
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Viral vectors as a novel tool for clinical and neuropsychiatric research applications 被引量:2
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作者 Yao Wang Zhiwei Hu +4 位作者 Peijun Ju Shan Yin Fujie Wang Oudong Pan Jinghong Chen 《General Psychiatry》 CSCD 2018年第5期100-108,共9页
Background A viral vector is a genetically modified vector produced by genetic engineering. As pathogenic genes in the virus are completely or largely eliminated, it is safe to be widely used in multidisciplinary rese... Background A viral vector is a genetically modified vector produced by genetic engineering. As pathogenic genes in the virus are completely or largely eliminated, it is safe to be widely used in multidisciplinary research fields for expressing genes, such as neuroscience, metabolism, oncology and so on. Neuroscience and psychiatry are the most closely related disciplines in either basic research or clinical research, but the application of viral vectors in neuropsychiatry has not received much attention or not been widely accepted.Aim This article will focus on the application of viral vectors in basic and clinical neuropsychiatric research.Methods By using viral vectors, scientists can perform neurological labelling, gene expression regulation and physiological manipulation for investigating phenomenon from molecular mechanisms to behaviours. At the same time, to treat mental or neurological disorders, viral vectors can be designed for gene therapy, which alter gene expression levels or repair mutated genes in the brains of patients.Perspective Viral vectors play an important role in basic research and clinical applications. To further understand brain function and prevent mental and neurological diseases, we hypothesize that viral vectors could be used along with various advanced technologies, such as sequencing and high-throughput expression analysis in the neuroscience research field. 展开更多
关键词 Methods By using VIRAL vectors NEUROSCIENCE and PSYCHIATRY
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Differentiation Character of Adult Mesenchymal Stem Cells andTransfection of MSCs with Lentiviral Vectors 被引量:3
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作者 张夏毅 李劲松 +4 位作者 聂君 江科 郑志坤 王建军 沈霖 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第6期687-693,共7页
This study examined the differentiation character and pluripotency of mesenchymal stem cells (MSCs) under different conditions. Adult MSCs were initially isolated from the bone marrow of rats, cultured in vitro and id... This study examined the differentiation character and pluripotency of mesenchymal stem cells (MSCs) under different conditions. Adult MSCs were initially isolated from the bone marrow of rats, cultured in vitro and identified by flow cytometry. After MSCs were transferred to osteogenic and adipogenic medium respectively, the morphological characterization of induced cells was observed. The expression of marker genes was detected by RT-PCR analysis. Then MSCs were transfected with lenti- viral vectors pGC-FU-Sox9-EGFP. Enhanced green fluorescence protein (EGFP) expression and trans- fection efficiency were determined by fluorescence microscopy. The results demonstrated that EGFP caused no effect on the multilineage potential of adult MSCs. Sox9 gene expression of high level was maintained stable in the transfected MSCs and induced MSCs to differentiate into chondrocytes. Ag- gracan was positive in chondrogenic lineages and the expression of aggracan and type Ⅱ collagenwas significantly increased during MSCs chondrogenic differentiation. It was concluded that Sox9 gene-modified adult MSCs may be promising candidate cells for further studies on tissue engineering. EGFP facilitates the research on MSCs physiological behavior and application in tissue engineering during differentiation both in vitro and in vivo. 展开更多
关键词 mesenchymal stem cells cell differentiation lentiviral vectors
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New Progress regarding the Use of Lactic Acid Bacteria as Live Delivery Vectors, Treatment of Diseases and Induction of Immune Responses in Different Host Species Focusing on <i>Lactobacillus</i>Species 被引量:5
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作者 Seria Masole Shonyela Guan Wang +2 位作者 Wentao Yang Guilian Yang Chunfeng Wang 《World Journal of Vaccines》 2017年第4期43-75,共33页
Lactobacillus species are non-spore-forming, gram-positive bacteria and lactic acid producing bacteria (LAPB) that naturally inhabit the human and animal gastrointestinal and mouth organs. The aim of this review was t... Lactobacillus species are non-spore-forming, gram-positive bacteria and lactic acid producing bacteria (LAPB) that naturally inhabit the human and animal gastrointestinal and mouth organs. The aim of this review was to evaluate the new progress regarding the use of Lactobacillus species as live delivery vectors, prevention, and treatment of pathogenic and metabolic diseases. Lactobacillus strains of probiotics have been extensively studied and have confirmed that they can absolutely improve performance as live delivery vectors, a treatment option of various diseases such as: Hemorrhagic cecal coccidiosis in young poultry, hypertension, avian flu, obesity, diabetes, Derzsy’s disease or parvovirus infection, human immunodeficiency virus infections, irritable bowel syndrome, gastrointestinal disorders, Fungal infections, vaginal eubiosis, fish and shellfish species diseases. We give you an idea about that Lactobacillus species have been proficient in preventing and treating both disorders in animal models and some are used for clinical trials. We present the most current studies on the use of Lactobacillus strains that had an impact on an effective immune response to a specific antigen because a variety of antigens have been expressed. Therefore Lactobacillus strains can be considered as good candidates because of its potential for diseases treatment and vaccine development as heterologous protein secretion to date. 展开更多
关键词 LACTOBACILLI Probiotics Lactic Acid LIVE Delivery vectors TREATMENT Immune Responses
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CYCCYCLIC VECTORS AND CELLULAR INDECOMPOSABLE OPERATORS ON Q_p SPACES 被引量:2
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作者 叶善力 娄增建 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期434-440,共7页
We identify the functions whose polynomial multiples are weak* dense in Qp spaces and prove that if |f(z)| ≥ |g(z)| and g is cyclic in Qp, then f is cyclic in Qp. We also show that the multiplication operato... We identify the functions whose polynomial multiples are weak* dense in Qp spaces and prove that if |f(z)| ≥ |g(z)| and g is cyclic in Qp, then f is cyclic in Qp. We also show that the multiplication operator Mx on Qp spaces is cellular indecomposable. 展开更多
关键词 Cyclic vectors Outer functions Cellular indecomposable Qp spaces
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CASH SUBADDITIVE RISK MEASURES FOR PORTFOLIO VECTORS 被引量:2
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作者 刘红卫 胡亦钧 魏林晓 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期361-376,共16页
In this paper, from the viewpoint of the time value of money, we study the risk measures for portfolio vectors with discount factor. Cash subadditive risk measures for portfolio vectors are proposed. Representation re... In this paper, from the viewpoint of the time value of money, we study the risk measures for portfolio vectors with discount factor. Cash subadditive risk measures for portfolio vectors are proposed. Representation results are given by two different methods which are convex analysis and enlarging space. Especially, the method of convex analysis make the line of reasoning and the representation result be simpler. Meanwhile, spot and forward risk measures for portfolio vectors are also introduced, and the relationships between them are investigated. 展开更多
关键词 cash subadditivity risk measures convex analysis portfolio vectors
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A Review of Agricultural Pesticides Use and the Selection for Resistance to Insecticides in Malaria Vectors 被引量:4
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作者 Anitha Philbert Sylvester Leonard Lyantagaye Gamba Nkwengulila 《Advances in Entomology》 2014年第3期120-128,共9页
Most national malaria control programmes rely extensively on pyrethroid insecticides to control mosquito vectors of this disease. Unfortunately, the intensive use of this class of insecticides both in public health an... Most national malaria control programmes rely extensively on pyrethroid insecticides to control mosquito vectors of this disease. Unfortunately, the intensive use of this class of insecticides both in public health and agriculture has led to its reduced efficacy. The objective of this review was to assess the role of agricultural pesticides use on the development of resistance to insecticides in malaria vectors and the potential impact of this resistance on control activities. We searched library catalogues and public databases for studies that included data on resistance to the major classes of insecticides: organochlorines, carbamates, organophosphates and pyrethroids, in the malaria vectors of Anopheles genera. There is a strong geographical bias in published studies many originating from West African countries. Several studies demonstrate that resistance to pyrethroids is widespread in the major malaria vectors of the Anopheles gambiae and Anopheles funestus complexes. Assessing the impact of insecticide resistance on vector control is complicated owing to the lack of studies into the epidemiological consequences of resistance on the control of malaria and other vector borne diseases. 展开更多
关键词 INSECTICIDE RESISTANCE Malaria vectors RESISTANCE Patterns Agro PESTICIDE PYRETHROIDS
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A phase analysis of vorticity vectors associated with tropical convection 被引量:1
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作者 崔晓鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2304-2310,共7页
Three new vorticity vectors have been proposed by Gao et al to study the two-dimensional tropical convection. In the present paper, phase relations between surface rain rate and the vorticity vectors are analysed with... Three new vorticity vectors have been proposed by Gao et al to study the two-dimensional tropical convection. In the present paper, phase relations between surface rain rate and the vorticity vectors are analysed with the calculations of lag correlation coefficients based on hourly zonally-averaged mass-integrated cloud-resolving simulation data. The cloud-resolving model is integrated with the vertical velocity, zonal wind, horizontal thermal and moisture advections, and sea surface temperature observed and derived from tropical ocean global atmosphere - coupled ocean atmosphere response experiment (TOGA-COARE) for 10 days. Maximum local increase of the vertical component of the convective vorticity vector leads maximum surface rain rate by 2 hours mainly due to the interaction between vorticity and zonal gradient of ice heating. While maximum local increase of the vertical component of the moist vorticity vector leads maxfinum surface rain rate by 2 hours mainly because of the interaction between zonal specific humidity gradient and zonal buoyancy gradient. And the maximum local decrease of the zonal component of the dynamic vorticity vector leads maximum surface rain rate by 2 hours mainly due to the interactions between vorticity and vertical pressure gradient as well as vorticity and buoyancy. 展开更多
关键词 phase analysis vorticity vectors tropical convection cloud-resolving model
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Use of PEI-coated Magnetic Iron Oxide Nanoparticles as Gene Vectors 被引量:1
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作者 韦卫中 徐春芳 吴华 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2004年第6期618-620,共3页
Summary: To evaluate the feasibility of using polyethyleneimine (PEI) coated magnetic iron oxide nanoparticles (polyMAG-1000) as gene vectors. The surface characteristics of the nanoparticles were observed with scanni... Summary: To evaluate the feasibility of using polyethyleneimine (PEI) coated magnetic iron oxide nanoparticles (polyMAG-1000) as gene vectors. The surface characteristics of the nanoparticles were observed with scanning electron microscopy. The ability of the nanoparticles to combine with and protect DNA was investigated at different PH values after polyMAG-1000 and DNA were combined in different ratios. The nanoparticles were tested as gene vectors with in vitro transfection models. Under the scanning electron microscope the nanoparticles were about 100 nm in diameter. The nanoparticles could bind and condense DNA under acid, neutral and alkaline conditions, and they could transfer genes into cells and express green fluorescent proteins (GFP). The transfection efficiency was highest (51 %) when the ratio of nanoparticles to DNA was 1:1 (v:w). In that ratio, the difference in transfection efficiency was marked depending on whether a magnetic field was present or not: about 10 % when it was absent but 51 % when it was present. The magnetic iron oxide nanoparticles coated with PEI may potentially be used as gene vectors. 展开更多
关键词 magnetic iron oxide nanoparticles POLYETHYLENEIMINE non-viral vectors gene therapy
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MicroRNA-regulated viral vectors for gene therapy 被引量:9
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作者 Anja Geisler Henry Fechner 《World Journal of Experimental Medicine》 2016年第2期37-54,共18页
Safe and effective gene therapy approaches require targeted tissue-specific transfer of a therapeutic transgene.Besides traditional approaches, such as transcriptional and transductional targeting, micro RNA-dependent... Safe and effective gene therapy approaches require targeted tissue-specific transfer of a therapeutic transgene.Besides traditional approaches, such as transcriptional and transductional targeting, micro RNA-dependent posttranscriptional suppression of transgene expression has been emerging as powerful new technology to increase the specificity of vector-mediated transgene expression. Micro RNAs are small non-coding RNAs and often expressed in a tissue-, lineage-, activation- or differentiation-specific pattern. They typically regulate gene expression by binding to imperfectly complementary sequences in the 3' untranslated region(UTR) of the m RNA. To control exogenous transgene expression, tandem repeats of artificial micro RNA target sites are usually incorporated into the 3' UTR of the transgene expression cassette, leading to subsequent degradation of transgene m RNA in cel s expressing the corresponding micro RNA. This targeting strategy, first shown for lentiviral vectors in antigen presenting cells, has now been used for tissue-specific expression of vector-encoded therapeutic transgenes, to reduce immune response against the transgene, to control virus tropism for oncolytic virotherapy, to increase safety of live attenuated virus vaccines and to identify and select cell subsets for pluripotent stem cell therapies, respectively. This review provides an introduction into the technical mechanism underlying micro RNA-regulation, highlights new developments in this field and gives an overview of applications of micro RNA-regulated viral vectors for cardiac, suicide gene cancer and hematopoietic stem cell therapy, as well as for treatment of neurological and eye diseases. 展开更多
关键词 Micro RNA Micro RNA regulation Micro RNA target sites Viral vectors Adeno-associated virus RNA interference Gene therapy Vector targeting
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Finite Control Set Model Predictive Current Control of a Five-Phase PMSM with Virtual Voltage Vectors and Adaptive Control Set 被引量:5
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作者 Wusen Wang Ying Fan +1 位作者 Siyu Chen Qiushi Zhang 《CES Transactions on Electrical Machines and Systems》 2018年第1期136-141,共6页
This paper presents an improved finite control set model predictive current control(FCS-MPCC)of a five-phase permanent magnet synchronous motor(PMSM).First,to avoid including all the 32 voltage vectors provided by a t... This paper presents an improved finite control set model predictive current control(FCS-MPCC)of a five-phase permanent magnet synchronous motor(PMSM).First,to avoid including all the 32 voltage vectors provided by a two-level five-phase inverter into the control set,virtual voltage vectors are adopted.As the third current harmonics can be much reduced by virtual voltage vectors automatically,the harmonic items in the cost function of conventional FCS-MPCC are not considered.Furthermore,an adaptive control set is proposed based on voltage prediction.Best control set with proper voltage vector amplitude corresponding to different rotor speed can be achieved by this method.Consequently,current ripples can be largely reduced and the system performs much better.At last,simulations are established to verify the steady and transient performance of the proposed FCS-MPCC,and experiments based on a 2 kW five-phase motor are carried out.The results have validated the performance improvement of the proposed control strategy. 展开更多
关键词 Adaptive control set current ripple finite control set model predictive current control(FCS-MPCC) permanent magnet synchronous motor(PMSM) virtual voltage vectors
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