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Truncating PICK1 Variant Identified in Azoospermia Affected Mitochondrial Dysfunction in Knockout Mice
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作者 Yao-qiang DU Chong-yi SHU +11 位作者 Min ZHENG Wei-de XU Yue SUN Lu SHEN Chen ZHANG Yu-xin ZHANG Qian-ni WANG Kai-qiang LI Bing-yu CHEN Ke HAO Jian-xin LYU Zhen WANG 《Current Medical Science》 SCIE CAS 2023年第2期313-323,共11页
Objective The protein interacting with C kinase 1(PICK1)plays a critical role in vesicle trafficking,and its deficiency in sperm cells results in abnormal vesicle trafficking from Golgi to acrosome,which eventually di... Objective The protein interacting with C kinase 1(PICK1)plays a critical role in vesicle trafficking,and its deficiency in sperm cells results in abnormal vesicle trafficking from Golgi to acrosome,which eventually disrupts acrosome formation and leads to male infertility.Methods An azoospermia sample was filtered,and the laboratory detection and clinical phenotype indicated typical azoospermia in the patient.We sequenced all of the exons in the PICK1 gene and found that there was a novel homozygous variant in the PICK1 gene,c.364delA(p.Lys122SerfsX8),and this protein structure truncating variant seriously affected the biological function.Then we constructed a PICK1 knockout mouse model using clustered regularly interspaced short palindromic repeat cutting technology(CRISPRc).Results The sperm from PICK1 knockout mice showed acrosome and nucleus abnormalities,as well as dysfunctional mitochondrial sheath formation.Both the total sperm and motility sperm counts were decreased in the PICK1 knockout mice compared to wild-type mice.Moreover,the mitochondrial dysfunction was verified in the mice.These defects in the male PICK1 knockout mice may have eventually led to complete infertility.Conclusion The c.364delA novel variant in the PICK1 gene associated with clinical infertility,and pathogenic variants in the PICK1 may cause azoospermia or asthenospermia by impairing mitochondrial function in both mice and humans. 展开更多
关键词 PICK1 AZOOSPERMIA truncating variant knockout mice mitochondrial dysfunction
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Otof gene transfer in DFNB9 mice carrying human founder non-truncating alleles
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作者 Yehree Kim Yoojin Chung +19 位作者 Ju Ang Kim Kyu Hee Han Kwon Woo Kang Ngoc-Trinh Tran Min Young Kim Eunyoung Yi Sangyong Jung Bong Jik Kim Quynh-Anh Artinian Seth D.Koehler Ning Pan Tyler M.Gibson Lars Becker Joseph W.Goodliffe Molly Kalker Madeline Barnes Luke A.Shaheen Meghan C.Drummond Vassili Valayannopoulos Byung Yoon Choi 《Genes & Diseases》 2025年第5期31-35,共5页
Gene therapy has shown promise for treating sensorineural hearing loss, supported by numerous successful preclinical studies. From the perspective of translation to humans, researchers have focused more on the genetic... Gene therapy has shown promise for treating sensorineural hearing loss, supported by numerous successful preclinical studies. From the perspective of translation to humans, researchers have focused more on the genetic causes of profound sensorineural hearing loss, where the sensory epithelium remains viable and intact for a considerable time after birth in humans. A key human deafness gene that best fits such a context is OTOF (GenBank AF183185.1), of which protein products, otoferlin, is essential for synaptic exocytosis and vesicle replenishment at the inner hair cell level in the cochlea. 展开更多
关键词 sensorineural hearing loss human founder non truncating alleles dfnb mice gene transfer preclinical studies sensory epithelium gene therapy protein products
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Differentially private high-dimensional data publication via grouping and truncating techniques 被引量:4
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作者 Ning WANG Yu GU +2 位作者 Jia XU Fangfang LI Ge YU 《Frontiers of Computer Science》 SCIE EI CSCD 2019年第2期382-395,共14页
The count of one column for high-dimensional datasets, i.e., the number of records containing this column, has been widely used in nuinerous applications such as analyzing popular spots based on check-in location info... The count of one column for high-dimensional datasets, i.e., the number of records containing this column, has been widely used in nuinerous applications such as analyzing popular spots based on check-in location information and mining valuable items from shopping records. However, this poses a privacy threat when directly publishing this information. Differential privacy (DP), as a notable paradigm for strong privacy guarantees, is thereby adopted to publish all column counts. Prior studies have verified that truncating records or grouping columns can effectively improve the accuracy of published results. To leverage the advantages of the two techniques, we combine these studies to further boost the accuracy of published results. However, the traditional penalty function, which measures the error imported by a given pair of parameters including truncating length and group size, is so sensitive that the derived parameters deviate from the optimal parameters significantly. To output preferable parameters, we first design a smart penalty function that is less sensitive than the traditional function. Moreover, a two-phase selection method is proposed to compute these parameters efficiently, together with the improvement in accuracy. Extensive experiments on a broad spectrum of real-world datasets validate the effectiveness of our proposals. 展开更多
关键词 differential privacy HIGH-DIMENSIONAL data TRUNCATION optimization GROUPING PENALTY function
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A Novel Mouse Model Unveils Protein Deficiency in Truncated CDKL5 Mutations
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作者 Xue Feng Zi-Ai Zhu +5 位作者 Hong-Tao Wang Hui-Wen Zhou Ji-Wei Liu Ya Shen Yu-Xian Zhang Zhi-Qi Xiong 《Neuroscience Bulletin》 2025年第5期805-820,共16页
Mutations in the cyclin-dependent kinase-like 5 gene(CDKL5)cause a severe neurodevelopmental disorder,yet the impact of truncating mutations remains unclear.Here,we introduce the Cdkl5^(492stop) mouse model,mimicking ... Mutations in the cyclin-dependent kinase-like 5 gene(CDKL5)cause a severe neurodevelopmental disorder,yet the impact of truncating mutations remains unclear.Here,we introduce the Cdkl5^(492stop) mouse model,mimicking C-terminal truncating mutations in patients.492stop/Y mice exhibit altered dendritic spine morphology and spontaneous seizure-like behaviors,alongside other behavioral deficits.After creating cell lines with various Cdkl5 truncating mutations,we found that these mutations are regulated by the nonsense-mediated RNA decay pathway.Most truncating mutations result in CDKL5 protein loss,leading to multiple disease phenotypes,and offering new insights into the pathogenesis of CDKL5 disorder. 展开更多
关键词 Cdkl5 truncating mutations CDKL5 defciency disorder Nonsense-mediated RNA decay
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On some multiple solutions to a p(x)-Laplace equation with supercritical growth
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作者 Lin Zhao 《中国科学技术大学学报》 北大核心 2025年第5期15-20,14,I0001,共8页
We consider the multiplicity of solutions to a p(x)-Laplacian problem involving supercritical Sobolev growth via Ricceri’s principle.By means of truncation combined with De Giorgi iteration,we can extend the results ... We consider the multiplicity of solutions to a p(x)-Laplacian problem involving supercritical Sobolev growth via Ricceri’s principle.By means of truncation combined with De Giorgi iteration,we can extend the results of subcritical and critical growth to supercritical growth and obtain at least three solutions to the p(x)-Laplacian problem. 展开更多
关键词 degenerate elliptic equations a priori estimates truncated technique supercritical Sobolev exponent
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Real pairwise completely positive matrices
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作者 ZHOU Anwa HE Jiayi 《运筹学学报(中英文)》 北大核心 2025年第3期160-178,共19页
In this paper,we introduce the real pairwise completely positive(RPCP)matrices with one of them is necessarily positive semidefinite while the other one is necessarily entrywise nonnegative,which has a real pairwise c... In this paper,we introduce the real pairwise completely positive(RPCP)matrices with one of them is necessarily positive semidefinite while the other one is necessarily entrywise nonnegative,which has a real pairwise completely positive(RPCP)decomposition.We study the properties of RPCP matrices and give some necessary and sufficient conditions for a matrix pair to be RPCP.First,we give an equivalent decomposition for the RPCP matrices,which is different from the RPCP-decomposition and show that the matrix pair(X,X)is RPCP if and only if X is completely positive.Besides,we also prove that the RPCP matrices checking problem is equivalent to the separable completion problem.A semidefinite algorithm is also proposed for detecting whether or not a matrix pair is RPCP.The asymptotic and finite convergence of the algorithm are also discussed.If it is RPCP,we can further give a RPCP-decomposition for it;if it is not,we can obtain a certificate for this. 展开更多
关键词 real pairwise completely positive matrices truncated moment problem semidefinite relaxation
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Fluvio-hydrological characteristics and diverse bedrock geology control the dynamic growth,truncation,and amalgamation of bedrock streambed and marine potholes
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作者 Biswajit Bera Sumana Bhattacharjee +7 位作者 Uttam Mukhopadhyay Debasis Sengupta Pravat Kumar Shit Nairita Sengupta Supriya Ghosh Arijit Ghosh Soumik Saha Sudipa Sarkar 《River》 2025年第1期84-105,共22页
A total of 393 potholes(368 fluvial and 25 marine potholes)were studied at seven different sites in both the fluvial and marine environments.Diverse bedrock properties and large-scale delivery of tools and grinders re... A total of 393 potholes(368 fluvial and 25 marine potholes)were studied at seven different sites in both the fluvial and marine environments.Diverse bedrock properties and large-scale delivery of tools and grinders regulate the dynamic growth,truncation,and amalgamation of potholes.Therefore,the principal objectives of the study are(i)to examine the relationship between the growth of potholes and substrate lithological with structural characteristics(applying geospatial and Schmidt hammer for rock strength analysis)and(ii)to measure the morphology,and size of tools and grinders,processes of truncation and amalgamation in hydro-geomorphic environment using various indices and field techniques.The result showed that large potholes are stretched in the direction of lineament axes and roughly parallel to the river flow direction.Here,the steady growth of pothole depth-diameter is controlled by active bedrock structures,tools,or grinders,and monsoonal high-velocity bank full discharge.Consequently,the deepening and widening of potholes are relatively slow at Bindu,Deuli,and marine beach Neil Island due to fewer structures and little supply of tools or grinders.In small stretches,(Damodar,Subarnarekha,and Rarhu)canyons and gorge-like features(bedrock incision)are formed at Rajrappa,Bhakuyadi,and Guridih sites due to cyclic truncation and amalgamation.Truncation and amalgamation processes restrict the vertical depth threshold value of potholes within 3m,particularly at Rajrappa,Bhakuyadi,and Guridih sites.Scientific study of the pothole's dynamic growth is greatly necessary for the different environmental engineering and river hydraulic projects like excavation,dredging,and dam or barrage construction.Successively,it is essential to compute the cost of rock excavation or dredging,primarily for the mechanical strength of the bedrock river channel and its stability. 展开更多
关键词 bedrock structures rock strength Schmidt hammer rebound values toolsand grinders truncation and amalgamation
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Post-translational cleavage generates truncated IgY forms in the snake Elaphe taeniura
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作者 Ming Zhang Long Hua +10 位作者 Tang-Yuan Xie Tao Wang Li-Juan Du Di Yu Han-Wei Cao Jin-Cheng Zhong Geng-Sheng Cao Xiang Ding Hai-Tang Han Yao-Feng Zhao Tian Huang 《Zoological Research》 2025年第2期277-284,共8页
While variable regions of immunoglobulins are extensively diversified by V(D)J recombination and somatic hypermutation in vertebrates,the constant regions of immunoglobulin heavy chains also utilize certain mechanisms... While variable regions of immunoglobulins are extensively diversified by V(D)J recombination and somatic hypermutation in vertebrates,the constant regions of immunoglobulin heavy chains also utilize certain mechanisms to produce diversity,including class switch recombination(CSR),subclass differentiation,and alternative expression of the same gene.Many species of birds,reptiles,and amphibians express a truncated isoform of immunoglobulin Y(IgY),termed IgY(ΔFc),which lacks theυCH3 andυCH4 domains.In Anseriformes,IgY(ΔFc)arises from alternative transcriptional termination sites within the sameυgene,whereas in some turtles,intact IgY and IgY(ΔFc)are encoded by distinct genes.Different from the previously reported IgY(ΔFc)variants,this study identified a truncated IgY in the snake Elaphe taeniura,characterized by the loss of only a portion of the CH4 domain.Western blotting and liquid chromatographytandem mass spectrometry confirmed that this truncated IgY is generated by post-translational cleavage at N338 within the IgY heavy chain constant(CH)region.Furthermore,both human and snake asparaginyl endopeptidase were shown to cleave snake IgY in vitro.These findings reveal a novel mechanism for the production of shortened IgY forms,demonstrating that the immunoglobulin CH region undergoes diversification through distinct strategies across vertebrates. 展开更多
关键词 Truncated IgY Post-translational cleavage Asparaginyl endopeptidase
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Nonlinear vibrations of axially transporting viscoelastic plates immersed in liquids
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作者 Dengbo ZHANG Qingke ZHOU +1 位作者 Xiangfei JI Youqi TANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第12期2341-2360,共20页
In industrial applications,plate-like structures such as steel strips in continuous hot-dip galvanizing and papers under fan action are ubiquitous.The vibration issues that arise when these structures are in axial mot... In industrial applications,plate-like structures such as steel strips in continuous hot-dip galvanizing and papers under fan action are ubiquitous.The vibration issues that arise when these structures are in axial motion,and are influenced by fluids and thermal fields,have attracted significant attention from the academic community.This study focuses on the nonlinear dynamic behavior of axially transporting immersed viscoelastic plates with particular emphasis on internal resonance and speed-dependent tension.The governing equation and the related boundary conditions for the axially transporting viscoelastic immersed plate are derived with Hamilton's principle,prioritizing the impact of time-varying tension induced by speed perturbations.Based on the second-order Galerkin truncation,the governing equation is discretized into a system of second-order ordinary differential equations.The multi-scale method is used to analyze the stable steady-state response of the immersed viscoelastic plate.The conditions for achieving a 3:1 frequency ratio between the first two orders of the system are analytically deduced.Notably,when the viscoelastic coefficient diminishes,the stability boundaries exhibit increased complexity,manifesting as the irregular W-shaped contours in the parameter space.Numerical examples comprehensively investigate the effects of viscoelasticity on both the stability region and the steady-state response under internal resonance conditions.Finally,the accuracy of the obtained results is validated through numerical computation. 展开更多
关键词 axially transporting viscoelastic plate internal resonance complete immersion perturbation technique Galerkin truncation method
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2006-2012年中国工业行业能源和环境综合效率及其影响因素 被引量:26
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作者 王娟 赵涛 张啸虎 《资源科学》 CSSCI CSCD 北大核心 2016年第2期311-320,共10页
能源消费量大、能源效率低以及环境问题突出已经成为中国发展面临的严峻挑战。由于工业部门能源消耗占中国能源消耗总量的70%左右,因此,本文基于工业36个子行业2006-2012年的数据,采用结合自然处置性和管理处置性概念的DEA模型将固定资... 能源消费量大、能源效率低以及环境问题突出已经成为中国发展面临的严峻挑战。由于工业部门能源消耗占中国能源消耗总量的70%左右,因此,本文基于工业36个子行业2006-2012年的数据,采用结合自然处置性和管理处置性概念的DEA模型将固定资产、能源消费及劳动力作为自然处置性下的投入,研发(R&D)投资额作为管理处置性下的投入,评价各子行业能源和环境综合效率以及R&D投资对各子行业减少非期望产出的有效性,最后,采用Truncated回归模型分析中国工业能源和环境综合效率的影响因素。研究结果表明:除烟草制品业等4个行业外,其余32个行业的综合效率均有改善空间,煤炭开采和洗选业、化学原料和化学制品制造业以及非金属矿物制品业等的综合效率值均在0.800以下,其中非金属矿物制品业效率值最低仅为0.472;2012年,研发投资对煤炭开采和洗选业等16个行业减少非期望产出是有效的;能源结构、技术创新和市场竞争对综合效率具有显著影响,其中煤炭在能耗中占比的提高对综合效率有抑制作用,而研发投资比例的提高对其则有促进作用。 展开更多
关键词 工业行业 能源和环境效率 DEA模型 Truncated模型 投资策略 中国
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丘陵山区地块尺度耕地生态效率及其影响因素分析 被引量:10
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作者 许标文 王海平 +1 位作者 杨军 郑百龙 《福建农业学报》 CAS 北大核心 2018年第12期1317-1323,共7页
耕地生态效率是评价耕地利用经济与环境绩效的有效测度。基于福建丘陵山区146块耕地的微观调查数据,利用Bootstrap-DEA模型计算耕地生态效率和投入变量的生态效率,并通过Double Bootstrap Truncated回归模型分析耕地生态效率影响因素。... 耕地生态效率是评价耕地利用经济与环境绩效的有效测度。基于福建丘陵山区146块耕地的微观调查数据,利用Bootstrap-DEA模型计算耕地生态效率和投入变量的生态效率,并通过Double Bootstrap Truncated回归模型分析耕地生态效率影响因素。研究发现:Bootstrap纠偏后的福建省丘陵山区耕地生态效率为0.610 7,化肥、农药及能源等投入变量的生态效率分别为0.679 9、0.575 5、0.481 9;Truncated回归结果显示耕地规模、教育程度、产品认证及复种指数对生态效率有显著影响,环境补贴对生态效率改善还未起作用。表明福建省丘陵山区耕地生态效率整体较为低下,应进一步推动土地适度规模经营、推广农业绿色发展技术及加大绿色生态农业补贴力度,以提高耕地生态效率。 展开更多
关键词 生态效率 Bootstrap-DEA DOUBLE BOOTSTRAP Truncated回归模型 地块尺度 丘陵山区
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Data fitting and modeling of regional geomagnetic field 被引量:3
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作者 冯彦 孙涵 蒋勇 《Applied Geophysics》 SCIE CSCD 2015年第3期303-316,465,466,共16页
The selection of the truncation level (TL) and the control of boundary effect (BE) are critical in regional geomagnetic field models that are based on data fitting. We combine Taylor and Legendre polynomials to mo... The selection of the truncation level (TL) and the control of boundary effect (BE) are critical in regional geomagnetic field models that are based on data fitting. We combine Taylor and Legendre polynomials to model geomagnetic data over China's Mainland for years 1960, 1970, 1990, and 2000. To tackle the TL and BE problems, we first determine the range of TL by calculating the root-mean-square error (RMSE) of the models. Next, we determine the optimum TL using the Akaike information criterion (AIC) and the normalized root- mean-square error (NRMSE). We use the regional anomaly addition (RAA) and the uniform addition (UA) method to add supplementary point outside the national boundary, and find that the intensities of extreme points gradually decrease and stabilize. The UA method better controls BEs over China, whereas the RAA method does a better job at smaller scales. In summary, we rely on a three-step method to determine the optimum TL and propose criteria to determine the optimum number of supplementary points. 展开更多
关键词 Boundary effect truncation level Taylor polynomial Legendre polynomial IGRF 11 CM4
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多肉植物姬玉露组织培养体系的建立 被引量:4
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作者 托亚 刘百超 白玉娥 《分子植物育种》 CAS CSCD 北大核心 2019年第11期3703-3708,共6页
姬玉露是玉露最为常见的品种之一。本试验以姬玉露新生肉质叶为外植体,探索最佳外植体消毒方式,并研究不同激素配比对诱导姬玉露愈伤组织及其分化的影响,建立姬玉露组织培养快速繁殖体系。结果表明:以2%的次氯酸钠为消毒剂最佳消毒时间... 姬玉露是玉露最为常见的品种之一。本试验以姬玉露新生肉质叶为外植体,探索最佳外植体消毒方式,并研究不同激素配比对诱导姬玉露愈伤组织及其分化的影响,建立姬玉露组织培养快速繁殖体系。结果表明:以2%的次氯酸钠为消毒剂最佳消毒时间为9 min;诱导姬玉露愈伤组织的最佳培养基配方为MS+6-BA(1.0 mg/L)+2,4-D(0.3 mg/L);诱导姬玉露愈伤组织分化的最佳培养基配方为MS+6-BA(1.0 mg/L)+NAA(0.1 mg/L);诱导姬玉露生根的最佳培养基为1/2MS+IBA(0.6 mg/L),生根率能达到76.3%。再生植株移栽最佳的基质为草炭土:蛭石:珍珠岩=3:2:1,移栽成活率达100%。本试验通过组织培养的方法,解决姬玉露繁殖率低、生长慢、品质差等问题,从而为工厂化育苗提供技术支持。 展开更多
关键词 姬玉露(Haworthia cooperi var.truncate) 多肉植物 组织培养 愈伤组织
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An Explicit Difference Scheme with High Accuracy and Branching Stability for Solving Parabolic Partial Differential Equation 被引量:4
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作者 马明书 王肖凤 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期98-103,共6页
This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△... This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△x4). The stability condition is r=a△t/△x2<1/2. 展开更多
关键词 parabolic type equation explicit difference scheme high accuracy branching stability truncation er
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Occurrence and Control of Tetranychus truncatus and T. urticae on Corns of Yanbian Area 被引量:1
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作者 郑大浩 李真 金大勇 《Agricultural Science & Technology》 CAS 2016年第2期394-397,共4页
The situation of occurrence and hazards by Tetranychus truncatus and T. urticae on corns in test garden of Agricultural College of Yanbian University were narrated in detail. The characteristics of distribution and da... The situation of occurrence and hazards by Tetranychus truncatus and T. urticae on corns in test garden of Agricultural College of Yanbian University were narrated in detail. The characteristics of distribution and damage by T. truncates and T. urticae, morphological characteristics, the rule of currencies and its relation- ship with environment were summarized, and the methods of comprehensive treat- ment were put out, which could effectively control the hazard degree of T. truncates and T. urticae on corns. 展开更多
关键词 Tetranychus truncates Tetranychus urticae Corns OCCURRENCE Preven- tion and Control: Yanbian Area
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Characteristics of Pollen Germination and Storage of Zygocactus truncates
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作者 李玉萍 罗凤霞 盛芸洁 《Agricultural Science & Technology》 CAS 2015年第3期420-422,466,共4页
The research, based on pol ens of Zygocactus truncates during ful-bloom period, selected suitable culture medium and temperature for pol en germination and explored the effects of storage temperatures and pol en col e... The research, based on pol ens of Zygocactus truncates during ful-bloom period, selected suitable culture medium and temperature for pol en germination and explored the effects of storage temperatures and pol en col ection methods on pol en vitality of Zygocactus truncates and the results showed that the culture medium containing 200 g/L saccharose, 20 mg/L boric acid, and 20 mg/L calcium chloride is suitable for pol en germination of Zygocactus truncates; when the temperature kept below 20 ℃, pol en germination period last short, and germination rate kept higher;pol en germination performed better with filaments, and pol en tube grew wel . 展开更多
关键词 Zygocactus truncates Pol en germination Fluid medium STORABILITY
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Empirical Bayes Absolute Error Loss Estimation for Parameter of One-Side Truncation Distribution Families
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作者 李金平 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期20-22,共3页
In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0&... In this paper we propose an absolute error loss EB estimator for parameter of one-side truncation distribution families. Under some conditions we have proved that the convergence rates of its Bayes risk is o, where 0<λ,r≤1,Mn≤lnln n (for large n),Mn→∞ as n→∞. 展开更多
关键词 one-side truncation distribution families absolute error loss function empirical Bayes estimator convergence rates
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面向室内动态环境的半直接法RGB-D SLAM算法 被引量:28
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作者 高成强 张云洲 +2 位作者 王晓哲 邓毅 姜浩 《机器人》 EI CSCD 北大核心 2019年第3期372-383,共12页
为了解决室内动态环境下移动机器人的准确定位问题,提出了一种融合运动检测算法的半直接法RGB-D视觉SLAM(同时定位与地图创建)算法,它由运动检测、相机位姿估计、基于TSDF (truncated signed distance function)模型的稠密地图构建3个... 为了解决室内动态环境下移动机器人的准确定位问题,提出了一种融合运动检测算法的半直接法RGB-D视觉SLAM(同时定位与地图创建)算法,它由运动检测、相机位姿估计、基于TSDF (truncated signed distance function)模型的稠密地图构建3个步骤组成.首先,通过最小化图像光度误差,利用稀疏图像对齐算法实现对相机位姿的初步估计.然后,使用视觉里程计的位姿估计对图像进行运动补偿,建立基于图像块实时更新的高斯模型,依据方差变化分割出图像中的运动物体,进而剔除投影在图像运动区域的局部地图点,通过最小化重投影误差对相机位姿进行进一步优化,提升相机位姿估计精度.最后,使用相机位姿和RGB-D相机图像信息构建TSDF稠密地图,利用图像运动检测结果和地图体素块的颜色变化,完成地图在动态环境下的实时更新.实验结果表明,在室内动态环境下,本文算法能够有效提高相机位姿估计精度,实现稠密地图的实时更新,在提升系统鲁棒性的同时也提升了环境重构的准确性. 展开更多
关键词 动态环境 视觉SLAM(同时定位与地图创建) 半直接法 TSDF(truncated SIGNED DISTANCE function)模型 稠密地图
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A truncated implicit high-order finite-difference scheme combined with boundary conditions 被引量:2
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作者 常锁亮 刘洋 《Applied Geophysics》 SCIE CSCD 2013年第1期53-62,118,共11页
In this paper, first we calculate finite-difference coefficients of implicit finite- difference methods (IFDM) for the first and second-order derivatives on normal grids and first- order derivatives on staggered gri... In this paper, first we calculate finite-difference coefficients of implicit finite- difference methods (IFDM) for the first and second-order derivatives on normal grids and first- order derivatives on staggered grids and find that small coefficients of high-order IFDMs exist. Dispersion analysis demonstrates that omitting these small coefficients can retain approximately the same order accuracy but greatly reduce computational costs. Then, we introduce a mirrorimage symmetric boundary condition to improve IFDMs accuracy and stability and adopt the hybrid absorbing boundary condition (ABC) to reduce unwanted reflections from the model boundary. Last, we give elastic wave modeling examples for homogeneous and heterogeneous models to demonstrate the advantages of the proposed scheme. 展开更多
关键词 Implicit finite difference symmetric boundary condition high-order accuracy TRUNCATION absorbing boundary condition staggered grid numerical modeling
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A two-stage frequency-domain blind source separation method for underdetermined instantaneous mixtures 被引量:1
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作者 彭天亮 陈阳 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期135-140,共6页
In order to decrease the probability of missing some data points or noises being added in the inverse truncated mixing matrix (ITMM) algorithm, a two-stage frequency- domain method is proposed for blind source separ... In order to decrease the probability of missing some data points or noises being added in the inverse truncated mixing matrix (ITMM) algorithm, a two-stage frequency- domain method is proposed for blind source separation of underdetermined instantaneous mixtures. The separation process is decomposed into two steps of ITMM and matrix completion in the view that there are many soft-sparse (not very sparse) sources. First, the mixing matrix is estimated and the sources are recovered by the traditional ITMM algorithm in the frequency domain. Then, in order to retrieve the missing data and remove noises, the matrix completion technique is applied to each preliminary estimated source by the traditional ITMM algorithm in the frequency domain. Simulations show that, compared with the traditional ITMM algorithms, the proposed two-stage algorithm has better separation performances. In addition, the time consumption problem is considered. The proposed algorithm outperforms the traditional ITMM algorithm at a cost of no more than one- fourth extra time consumption. 展开更多
关键词 inverse truncated mixing matrix under-determined blind source separation (UBSS) frequencydomain matrix completion
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