期刊文献+
共找到12,356篇文章
< 1 2 250 >
每页显示 20 50 100
Wild soybean(Glycine soja)transcription factor GsWRKY40 plays positive roles in plant salt tolerance
1
作者 Minglong Li Man Xue +7 位作者 Huiying Ma Peng Feng Tong Chen Xiaohuan Sun Qiang Li Xiaodong Ding Shuzhen Zhang Jialei Xiao 《The Crop Journal》 SCIE CSCD 2024年第3期766-775,共10页
Wild soybean(Glycine soja),a relative of cultivated soybean,shows high adaptability to adverse environmental conditions.We identified and characterized a wild soybean transcription factor gene,GsWRKY40,that promotes p... Wild soybean(Glycine soja),a relative of cultivated soybean,shows high adaptability to adverse environmental conditions.We identified and characterized a wild soybean transcription factor gene,GsWRKY40,that promotes plant salt stress.GsWRKY40 was highly expressed in wild soybean roots and was up-regulated by salt treatment.GsWRKY40 was localized in nucleus and demonstrated DNA-binding activities but without transcriptional activation.Mutation and overexpression of GsWRKY40 altered salt tolerance of Arabidopsis plants.To understand the molecular mechanism of GsWRKY40 in regulating plant salt resistance,we screened a cDNA library and identified a GsWRKY40 interacting protein GsbHLH92 by using yeast two-hybrid approach.The physical interaction of GsWRKY40 and GsbHLH92 was confirmed by co-immunoprecipitation(co-IP),GST pull-down,and bimolecular fluorescence complementation(BiFC)techniques.Intriguingly,co-overexpression of GsWRKY40 and GsbHLH92 resulted in higher salt tolerance and lower ROS levels than overexpression of GsWRKY40 or GsbHLH92 in composite soybean plants,suggesting that GsWRKY40 and GsbHLH92 may synergistically regulate plant salt resistance through inhibiting ROS production.qRT-PCR data indicated that the expression level of GmSPOD1 gene encoding peroxidase was cooperatively regulated by GsWRKY40 and GsbHLH92,which was confirmed by using a dual luciferase report system and yeast one-hybrid experiment.Our study reveals a pathway that GsWRKY40 and GsbHLH92 collaboratively up-regulate plant salt resistance through impeding GmSPOD1 expression and reducing ROS levels,providing a novel perspective on the regulatory mechanisms underlying plant tolerance to abiotic stresses. 展开更多
关键词 wild soybean Transcription factor Salt stress ROS
下载PDF
Wild Gibbon Optimization Algorithm
2
作者 Jia Guo JinWang +5 位作者 Ke Yan Qiankun Zuo Ruiheng Li Zhou He Dong Wang Yuji Sato 《Computers, Materials & Continua》 SCIE EI 2024年第7期1203-1233,共31页
Complex optimization problems hold broad significance across numerous fields and applications.However,as the dimensionality of such problems increases,issues like the curse of dimensionality and local optima trapping ... Complex optimization problems hold broad significance across numerous fields and applications.However,as the dimensionality of such problems increases,issues like the curse of dimensionality and local optima trapping also arise.To address these challenges,this paper proposes a novel Wild Gibbon Optimization Algorithm(WGOA)based on an analysis of wild gibbon population behavior.WGOAcomprises two strategies:community search and community competition.The community search strategy facilitates information exchange between two gibbon families,generating multiple candidate solutions to enhance algorithm diversity.Meanwhile,the community competition strategy reselects leaders for the population after each iteration,thus enhancing algorithm precision.To assess the algorithm’s performance,CEC2017 and CEC2022 are chosen as test functions.In the CEC2017 test suite,WGOA secures first place in 10 functions.In the CEC2022 benchmark functions,WGOA obtained the first rank in 5 functions.The ultimate experimental findings demonstrate that theWildGibbonOptimization Algorithm outperforms others in tested functions.This underscores the strong robustness and stability of the gibbonalgorithm in tackling complex single-objective optimization problems. 展开更多
关键词 Complex optimization wild gibbon optimization algorithm community search community competition
下载PDF
Comparative Study of Genetic Structure and Genetic Diversity betweenWild and Cultivated Populations of Taxus cuspidata,Northeast China
3
作者 Dandan Wang Xiaohong Li Yanwen Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期355-369,共15页
Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is... Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is,33 wild yews and 28 cultivated yews were used to analyze the differences and correlations of the kinship,genetic diversity,and genetic structure between them by specific length amplified fragment sequencing(SLAF-seq).Finally,470725 polymorphic SLAF tags and 58622 valid SNP markers were obtained.Phylogenetic analysis showed that 61 samples were classified into 2 clusters:wild populations and cultivated populations,and some wild yews were categorized into the cultivated populations;the genetic diversity analysis showed that the Nei diversity index of wild populations(0.4068)was smaller than that of cultivated populations(0.4414),and the polymorphic information content(PIC)of wild populations(0.2861)was smaller than that of cultivated populations(0.3309).The genetic differentiation analysis showed that the total populations of gene diversity(H_(t))of cultivated and wild populations were respectively 0.8159 and 0.5685,the coefficient of gene differentiation(G_(st))of cultivated and wild populations was respectively 0.3021 and 0.1068,and the gene flow(N_(m))(2.4967)of wild populations was larger than cultivated populations(0.8199).The molecular variance(AMOVA)revealed that inter-population variation accounted for 29.57%of the total genetic variation,while intra-population variation accounted for 70.42% of the total genetic variation(p<0.001),this suggested that the genetic variation in the T.cuspidata is mainly attributed to within-population factors.In conclusion,the genetic distance between geographical ecological groups of wild populations was generally smaller than that of cultivated populations,and the degree of genetic diversity and genetic differentiation was smaller than that of cultivated populations.As evident,the utilization of SLAF-seq technology enables efficient and accurate development of SNP markers suitable for genetic analysis of T.cuspidata species.These developed SNP markers can provide a molecular foundation for T.cuspidata breeding,construction of genetic maps,variety identification,and association analysis of agronomic traits. 展开更多
关键词 T.cuspidata SLAF-seq SNP wild population cultivated population genetic structure
下载PDF
Clinicopathological alterations in wild mammals from the reservoir system of Trypanosoma cruzi:a scoping review
4
作者 Ricardo Sanchez Pérez JoséManuel Aranda-Coello +1 位作者 JoséAntonio De Fuentes Vicente Oscar Rico Chavez 《Animal Diseases》 CAS 2024年第1期48-58,共11页
Trypanosoma cruzi is the etiologic agent of Chagas disease.This flagellated protozoan is transmitted to humans as well as different species of domestic and wild animals via vectors from the Reduviidae family(known as&... Trypanosoma cruzi is the etiologic agent of Chagas disease.This flagellated protozoan is transmitted to humans as well as different species of domestic and wild animals via vectors from the Reduviidae family(known as"kissing bugs").Despite the fact that hundreds of species of wild mammals are part of the reservoir system,the morphologi-cal changes and clinical manifestations resulting from the pathogenesis of the infection have been largely neglected.The aim of this review is to systematically compile the available information regarding clinicopathological altera-tions in wild mammals due to natural infection by T.cruzi.Information was obtained from six online bibliographic data search platforms,resulting in the identification of 29 publications that met the inclusion criteria.Mortality was the most common clinical manifestation,cardiac damage was the main finding at necropsy,and lymphoplas-macytic inflammation was the most frequent microscopic injury.Thus,regardless of its role as a reservoir,T.cruzi has the potential to affect the health status of wild mammals,a situation that highlights the need for further research to analyze,measure,and compare its effects at both the individual and population levels. 展开更多
关键词 Trypanosoma cruzi Chagas disease American trypanosomiasis Clinicopathological alterations Natural infection wild mammals
下载PDF
A Germplasm Resource Repository:The Book Review of Illustrated Flora of Food Crops and Their Wild Related Plants in China
5
作者 Yuting CHEN 《Asian Agricultural Research》 2024年第7期59-60,共2页
Illustrated Flora of Food Crops and Their Wild Related Plants in China systematically examines the botanical and morphological characteristics of China's major food crops,such as rice,wheat,corn,sweet potato,potat... Illustrated Flora of Food Crops and Their Wild Related Plants in China systematically examines the botanical and morphological characteristics of China's major food crops,such as rice,wheat,corn,sweet potato,potato,mung bean,and buckwheat.Featuring more than 5000 color photos and 200 line drawings,it offers a comparative study that highlights the kinship and internal connections between cultivated and wild species.The book is an invaluable resource for breeders,offering a comprehensive morphological and genetic database that aids in the development of high-yielding,high-quality,and disease-resistant crop varieties. 展开更多
关键词 Food security Crop improvement wild relatives Breeding resource Plant illustrations
下载PDF
Comprehensive Evaluation of Application Value of Wild Flower Resources in Flower Border in Hefei City
6
作者 ZHU Rong ZHAO Zhiyan +3 位作者 XU Huaxue MENG Yi GUAN Tianjing YIN Jia’ai 《Journal of Landscape Research》 2024年第3期48-50,58,共4页
In order to further understand and better develop and utilize wild flower resources in Hefei City,a comprehensive evaluation model of landscape value of wild flowers in the application of flower border was constructed... In order to further understand and better develop and utilize wild flower resources in Hefei City,a comprehensive evaluation model of landscape value of wild flowers in the application of flower border was constructed by field investigation and analytic hierarchy process(AHP).The application value of wild flowers in Hefei was evaluated by selecting evaluation indicators from three aspects of ornamental value,adaptability and resource potential. 展开更多
关键词 Analytic hierarchy process(AHP) wild flower resources Application value Comprehensive evaluation
下载PDF
Lightning in a Forest (Wild) Fire: Mechanism at the Molecular Level
7
作者 See Leang Chin Xueliang Guo +4 位作者 Harmut Schroeder Huanbin Xu Tie-Jun Wang Ruxin Li Weiwei Liu 《Atmospheric and Climate Sciences》 2024年第1期128-135,共8页
The mechanism of lightning that ignites a forest fire and the lightning that occurs above a forest fire are explained at the molecular level. It is based on two phenomena, namely, internal charge separation inside the... The mechanism of lightning that ignites a forest fire and the lightning that occurs above a forest fire are explained at the molecular level. It is based on two phenomena, namely, internal charge separation inside the atmospheric cloud particles and the existence of a layer of positively charged hydrogen atoms sticking out of the surface of the liquid layer of water on the surface of rimers. Strong turbulence-driven collisions of the ice particles and water droplets with the rimers give rise to breakups of the ice particles and water droplets into positively and negatively charged fragments leading to charge separation. Hot weather in a forest contributes to the updraft of hot and humid air, which follows the same physical/chemical processes of normal lightning proposed and explained recently[1]. Lightning would have a high probability of lighting up and burning the dry biological materials in the ground of the forest, leading to a forest (wild) fire. The burning of trees and other plants would release a lot of heat and moisture together with a lot of smoke particles (aerosols) becoming a strong updraft. The condition for creating lightning is again satisfied which would result in further lightning high above the forest wild fire. 展开更多
关键词 Forest wild Fire LIGHTNING Molecular Level
下载PDF
The Influence of Chuang Tsu on Oscar Wilde’s Literary Works
8
作者 XU Hai-hua 《Sino-US English Teaching》 2024年第3期138-141,共4页
Oscar Wilde,the renowned British writer,was deeply influenced by Eastern culture,particularly by Chuang Tsu’s“Thought of Doing Nothing”,a Taoist concept of human conduct.Wilde not only embraced this philosophy,but ... Oscar Wilde,the renowned British writer,was deeply influenced by Eastern culture,particularly by Chuang Tsu’s“Thought of Doing Nothing”,a Taoist concept of human conduct.Wilde not only embraced this philosophy,but also incorporated it into his literary creations and art criticism,enhancing the steadfastness of his own value judgments. 展开更多
关键词 Oscar wilde Chuang Tsu “Thought of Doing Nothing”
下载PDF
Genetic Diversity in Wild Populations of Poacynum hendersonii from Inland Arid Regions of Northwest China 被引量:21
9
作者 赵金凤 张卫明 +3 位作者 彭雪梅 唐泽紫 顾龚平 陆长梅 《Agricultural Science & Technology》 CAS 2008年第4期39-43,共5页
[Objective] Study on the genetic diversity in wild populations of Poacynum hendersonii.[Method] Random amplified polymorphic DNA(RAPD)technique was employed to analyze the genetic diversity in five wild populations of... [Objective] Study on the genetic diversity in wild populations of Poacynum hendersonii.[Method] Random amplified polymorphic DNA(RAPD)technique was employed to analyze the genetic diversity in five wild populations of P.hendersonii sampled from Xinjiang,Gansu and Qinghai provinces.[Result] Totally 165 clear and repeatable bands were generated in RAPD reaction by using 20 primers screened from 80 primers,of which 110 were polymorphic,accounting for 66.67%.At species level,Nei's gene diversity index(H),Shannon's information index(I)and genetic differentiation coefficient(Gst)were 0.220 5,0.304 7 and 0.908 2,respectively.P.hendersonii germplasm resources share a high level of genetic diversity,and genetic differentiation mainly exists among the populations.Results from genetic distances and cluster analysis showed that relationships among P.hendersonii populations were to some extent related with their geographical and climatic characters.[Conclusion] This study suggests that the conservation of P.hendersonii should focus on the protection of many populations,particularly the Qinghai population. 展开更多
关键词 Poacynum hendersonii wild POPULATION GENETIC diversity RAPD
下载PDF
Pro/E Wild Fire中零件库的建立方法 被引量:5
10
作者 石晶 焦洪宇 张涛 《机械设计与制造》 北大核心 2005年第5期137-138,共2页
以Pro/E Wild Fire软件为基础,详细地论述了零件库的建立方法,分析了每种方法的优缺点,提出了适用范围,使零件库的建立更加简单化,从而有效的提高了实体建模速度,缩短了设计周期。
关键词 PRO/ENGINEER wild Fire 族表 自定义特征 编程
下载PDF
Genetic Diversity in Wild Grapes Native to China Based on Randomly Amplified Polymorphic DNA (RAPD) Analysis 被引量:29
11
作者 罗素兰 贺普超 +1 位作者 郑学勤 周鹏 《Acta Botanica Sinica》 CSCD 2001年第2期158-163,共6页
The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one str... The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one strain of V. riparia L. Genetic diversity among these grapes was investigated based on RAPD analysis. The screening of 280 decamer oligonucleotides allowed the selection of 20 primers used for the analysis. A total of 191 RAPD markers were produced from the 20 selected primers. Relationships among the 83 clones or accessions based on their genetic distances were clustered using unweighted pair_group method arithmetic average (UPGMA) analysis in a dendrogram. Twenty_two clusters which fortunately adapted to 22 grape species level were clearly resolved on the dendrogram. The 18 wild grape species native to China were grouped into ten subclusters. The largest distance was found between V. riparia L., V. vinifera L., interspecific hybrid ( V. vinifera L.× V. larbrusca L.) and the wild grapes native to China. Among the wild grapes native to China, the largest distance was found between V. hancockii Hance and the other wild species. V. qinlingensis P.C.He was the second. Large genetic variation occurred among the different flower_type clones in one species. 展开更多
关键词 the wild grapes native to China VITIS genetic distance RAPD
下载PDF
Genetic Variation of Wild and Hatchery Populations of the Pacific Oyster Crassostrea gigas Assessed by Microsatellite Markers 被引量:10
12
作者 于红 李琪 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第12期1114-1122,共9页
Microsatellite DNA technique was used to detect the genetic variation between five hatchery populations of the Pacific oyster from China and two wild populations from Japan. Seven microsatellite loci screened in this ... Microsatellite DNA technique was used to detect the genetic variation between five hatchery populations of the Pacific oyster from China and two wild populations from Japan. Seven microsatellite loci screened in this study showed high polymorphism in both hatchery and wild populations, as observed in an average number of allele per locus (19.1-29.9) and average expected heterozygosity (0.916-0.958). No significant difference in average allelic richness or expected heterozygosity was observed between Chinese hatchery populations and Japanese wild populations. Pairwise Fsr values and heterogeneity tests of allele frequencies showed significant genetic differentiation between all populations. According to the neighbor-joining tree constructed on the basis of the Dc distance, the seven populations fell into three groups showing a clear division between hatchery and wild populations, and between the northern and southern hatchery populations. Assignment tests correctry assigned high percentages (97%-100%) of individuals to their original populations and demonstrated the feasibility of microsatellite analysis for discrimination between populations. The information obtained in this study is useful for designing suitable management guidelines and selective breeding programs for the Pacific oyster in China. 展开更多
关键词 Crassostrea gigas genetic variation HATCHERY wild MICROSATELLITE
下载PDF
Akebia ― a valuable wild fruit under domestication 被引量:4
13
作者 王中炎 钟彩虹 +3 位作者 卜范文 彭涤非 彭俊彩 袁飞荣 《Agricultural Science & Technology》 CAS 2005年第2期12-17,F0003,共7页
Akebia is a wild fruit originating in the Yangtse river valley and the surrounding areas. It includes mainly three species (subspecies): Akebia trifoliata, Akebia trifoliata subsp, australis, and Akebia quinata. It... Akebia is a wild fruit originating in the Yangtse river valley and the surrounding areas. It includes mainly three species (subspecies): Akebia trifoliata, Akebia trifoliata subsp, australis, and Akebia quinata. It has many good traits, such as large fruit size, early fruit-setting and high yield, excellent eating quality, and good environmental adaptability. However, there are some shortcomings with the fruit, including thick skin, excessive number of seeds, and relatively small proportion of edible flesh. Akebia is also a traditional Chinese medicine, which has the functions of relieving internal heat and diuresis, dredging venation and improving blood circulation, cleansing facial chloasma, detoxication and anti-cancer activities. Akebia can be used as fresh fruit, for processing, and for pharmaceutical purposes. We have been undertaking a series of research on the domestication and utilization of Akebia, including cultivar selection, techniques for cultivation, storage and processing, and related basic studies. A Chinese trade name “Hehuanguo” and an English trade name “Joyfruit” have been registered for Akebia to facilitate its commercial development. 展开更多
关键词 Akebia wild fruit DOMESTICATION Joyfruit
下载PDF
ITS1 SEQUENCES OF NUCLEAR RIBOSOMAL DNA IN WILD RICES AND CULTIVATED RICES OF CHINA AND THEIR PHYLOGENETIC IMPLICATIONS 被引量:22
14
作者 周毅 邹喻苹 +2 位作者 洪德元 周骏马 陈受宜 《Acta Botanica Sinica》 CSCD 1996年第10期785-791,共7页
The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced wi... The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced with automated fluorescent sequencing. The sequences of ITS1 ranged from 193 bp to 218 bp in size and G/C content varied from 69.3% to 72.7%. In pairwise comparisons among the five taxa, sequence site divergence ranged from 1.5% to 10.6%. Phylogenetic analysis of ITS1 sequences using Wagner parsimony generated a single well resolved tree, which revealed that Oryza rufipogon was much more closely related to cultivated rice species than to the other two wild species. Oryza granulata was less closely related to either cultivated rice species or the other two wild species, and might be a unique and isolated taxon in the genus Oryza. The phylogenetic relationships of the three wild rice species and two cultivated rice subspecies inferred from ITS1 sequences is highly concordant with those based on the molecular evidence from isozyme, chloroplast DNA (cpDNA), mitochondrial DNA(mtDNA) and nuclear DNA (nDNA) of the genus Oryza . 展开更多
关键词 wild rice Cultivated rice ITS1 of rDNA Sequence analysis PHYLOGENY
下载PDF
我国证券市场有效性的Wild Bootstrap方差比检验 被引量:17
15
作者 刘维奇 史金凤 《统计研究》 CSSCI 北大核心 2006年第11期73-78,共6页
This paper introduces the theory of market efficiency simply and surveys various methods and results of week form market efficiency test of China.Then we test the sample and propose to test the week form market effici... This paper introduces the theory of market efficiency simply and surveys various methods and results of week form market efficiency test of China.Then we test the sample and propose to test the week form market efficiency test of China using the wild bootstrap variance ratio test which has been found to exhibit better small sample properties.The results are conducted with moving sub-sample windows and found that Shanghai market has been efficient of week form but Shenzhen market hasn’t been efficiency of week form. 展开更多
关键词 市场有效性 方差比检验 wild BOOTSTRAP方法
下载PDF
Physiological Analysis on Mechanisms of Cold-tolerance of Dongxiang Wild Rice(Ⅰ) 被引量:4
16
作者 徐梅珍 刘晓 +4 位作者 余丽琴 刘世强 曾黎明 陈蓉蓉 王义华 《Agricultural Science & Technology》 CAS 2010年第2期39-43,共5页
[Objective] The research aimed to study the effects of soluble substance concentration in cell and the scavenging activity of active oxygen radicals on the cold-tolerance physiology of Dongxiang wild rice.[Method] Don... [Objective] The research aimed to study the effects of soluble substance concentration in cell and the scavenging activity of active oxygen radicals on the cold-tolerance physiology of Dongxiang wild rice.[Method] Dongxiang wild rice was used as materials to detect and compare the content of soluble sugar,free proline and soluble protein,POD activity,CAT activity,MDA content in the leaves in different growth periods.Using with control of two species of common cultivated rice Xieqingzao and Nongda 288.[Resul... 展开更多
关键词 Dongxiang wild rice Cold tolerance POD CAT
下载PDF
Identification of Endophytic Bacillus BHL3501 from Wild Soybean and Its Inhibitory Effect against Soybean Cyst Nematode (Heterodera glycines Ichinohe) 被引量:1
17
作者 朱英波 史凤玉 +3 位作者 李建英 龙茹 武云鹏 乔亚科 《Plant Diseases and Pests》 CAS 2011年第5期52-54,58,共4页
[ Objective] The paper was to identify endophytic bacillus BHL3501 from wild soybean and its inhibitory effect against soybean cyst nematode. [ Meth- od] Through morphological characteristic, physiological and biochem... [ Objective] The paper was to identify endophytic bacillus BHL3501 from wild soybean and its inhibitory effect against soybean cyst nematode. [ Meth- od] Through morphological characteristic, physiological and biochemical characteristics and 16S rDNA analysis, a strain of endophytic bacterium BHL3501 with ne- maticidal activity isolated and screened from the root of wild soybean was identified, the effects of BHL3501 metabolite solutions with different dilution multiples on egg hatching and activity of 2rd instar juvenile of soybean cyst nematode were also studied. [ Result ] BHL3501 strain was preliminarily identified to be Bacillus sp.. The relative inhibitory rate of its original fermentation broth on egg hatching of soybean cyst nematode after 24 h was 98.3% ; the relative inhibitory rate under 10- time diluted solution treatment was 79.5%, which had significant difference with sterile water control. The corrected mortality rate of 24 instar juvenile was 93.1% after treated by original fermentation broth for 24 h, the treatments of all diluted solutions had significant difference with sterile water control. [ Conclusion ] BHL3501 metabolites had strong inhibitory effect against egg hatching of soybean cyst nematode, which also had strong toxic effect on its 2nd instar juvenile. 展开更多
关键词 wild soybean Soybean cyst nematode Biological control Bacillus sp. 16S rDNA China
下载PDF
WILD:基于加权信息损耗的离散化算法 被引量:8
18
作者 李刚 李霁伦 童兆页 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2001年第2期148-153,共6页
现实应用中常常涉及许多连续的数值属性 ,而目前许多机器学习算法则要求所处理的属性具有离散值 .基于信息论的基本原理 ,提出一种新的有监督离散化算法WILD ,该算它可以看成是决策树离散化算法的一种扩充 ,其主要改进在于考虑区间内观... 现实应用中常常涉及许多连续的数值属性 ,而目前许多机器学习算法则要求所处理的属性具有离散值 .基于信息论的基本原理 ,提出一种新的有监督离散化算法WILD ,该算它可以看成是决策树离散化算法的一种扩充 ,其主要改进在于考虑区间内观测值出现的频度 ,采用加权信息损耗作为区间离散化的测度 ,以克服决策树算法离散不均衡的问题 .该算法非常自然地采用了自底向上的区间归并方案 ,可以同时归并多个相邻区间 ,有利于提高离散化算法的速度 .实验结果表明该算法能够提高机器学习算法的精度 . 展开更多
关键词 机器学习 离散化 加权信息损耗 wild 决策树 有监督算法
下载PDF
Induced Expression of Cytochrome P450 CYP305 B1V1 Gene in Different Tissues of Wild Mulberry Silkworm(Bombyx mandarina) 被引量:6
19
作者 路爱成 卫正国 +1 位作者 李兵 沈卫德 《Agricultural Science & Technology》 CAS 2009年第2期54-58,共5页
[ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA ... [ Objective] The aim of this study was to investigate effects of various inducers on the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm. [ Method] Referring to the mRNA sequence of CYP305 B1 V1 Gene published in GenBank for wild mulberry silkworm, one pair of primers was designed, and the expression of cytochrome P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm treated by NaF, rutin, cypermethrin and ecdysone was also analyzed by the semi - quantitative RT - PCR. Furthermore, homology comparison and phylogenetic analysis for amino acid sequences of this gene were studied. [ Result] Rutin, cypermethrin and NaF had effects on the expression of P450 CYP305 B1 V1 Gene in different tissues of wild mulberry silkworm, while ecdysone had no significant effect. Homology comparison for amino acids indicated that the amino acid sequence of this gene was the most similar to that of CYP305 B1 gene in Bombyx mori with 100% amino acid identity, and highly similar to those of Tribolium casmneum CYP305A1, Apis mellifera CYP305A1, Drosophi- la melanogaster CYP305A1, Anopheles gambiae CYP305A2and Culex pipiens quinquefasciatus CYP2LI. [ Conclusion] CYP305 B1 V1 Gene of wild mulberry silkworm is likely to mainly take part in the metabolism of exogenous compounds, which is of great significance for revealing the function of cytochrome P450 and the metabolic mechanism of different drugs. 展开更多
关键词 wild mulberry silkworm CYP305B1V1 INDUCE EXPRESSION Phylogenetic analysis
下载PDF
Wild Ornamental Plant Resources and Their Application to City Gardening in Hainan Province 被引量:1
20
作者 侯则红 余雪标 陈展川 《Journal of Landscape Research》 2009年第6期59-63,共5页
This paper deals with the wild ornamental plant resources which are suitable for the application to gardening in Hainan Province and with the significance and the influencing factors in the application and extension o... This paper deals with the wild ornamental plant resources which are suitable for the application to gardening in Hainan Province and with the significance and the influencing factors in the application and extension of these resources to gardening. The strategies for the application of the wild ornamental plant resources have been established as the result of this research. 展开更多
关键词 wild ORNAMENTAL plants HAINAN Province GARDENING CULTIVATION APPLICATION
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部