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An analysis of agarwood trade patterns,historical perspectives,and species identification challenges:repercussions for importing nations
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作者 Zhao-Qi Xie Jun-Yu Xu +1 位作者 Muhammad Rafiq Chun-Song Cheng 《TMR Modern Herbal Medicine》 CAS 2024年第1期1-10,共10页
Background:Agarwood,primarily derived from the Aquilaria and Gyrinops genera,holds significant economic importance.However,there is a lack of comprehensive investigations providing guidance to importing nations regard... Background:Agarwood,primarily derived from the Aquilaria and Gyrinops genera,holds significant economic importance.However,there is a lack of comprehensive investigations providing guidance to importing nations regarding cultivation quantities and expected yields of Agarwood from distinct species.This study aims to address this gap by exploring the historical context and trade evolution of Agarwood,highlighting its global importance,and the challenges associated with securing accurate species information.Method:On-site visits to Agarwood cultivation sites were conducted to gain a nuanced understanding of Aquilaria species and their cultivation requirements.Additionally,a thorough analysis of global export and import data for Agarwood products over the last decade was undertaken.Results:China Mainland emerged as the leading exporter of Agarwood,averaging an annual export value of USD 1 million.India’s substantial exports challenge the prevailing notion of limited Agarwood production within its borders.Hong Kong and Singapore are pivotal distribution hubs,while Hong Kong and Taipei feature prominently as import destinations.Our analysis uncovers anomalies in the representation of Agarwood producers from 2001 to 2008,suggesting potential misclassification of Aquilaria Agarwood as Gyrinops in global export information.These findings underscore the urgency of investigating classification and reporting practices in the Agarwood trade.Furthermore,A.filaria emerges as a notable source,while A.malaccensis is decline in prominence.Conclusion:This study provides crucial insights for policymakers,stakeholders,and industry players seeking to make informed decisions in the Agarwood trade landscape.The results highlight the need for accurate species identification,classification,and reporting practices to ensure sustainable cultivation and trade of Agarwood. 展开更多
关键词 AGARWOOD import and export trends global trade field visits industry analysis
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Research status and prospects of the fractal analysis of metal material surfaces and interfaces
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作者 Qinjin Dai Xuefeng Liu +2 位作者 Xin Ma Shaojie Tian Qinghe Cui 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期20-38,共19页
As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal... As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal materials at various scales and dimensions.Conventional methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and interfaces.However,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal materials.From the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear surfaces.The relationship between the fractal dimensions and properties of metal material surfaces and interfaces is summarized.Starting from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be developed.It is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future. 展开更多
关键词 metal material surfaces and interfaces fractal analysis fractal dimension HOMOGENEITY
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Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury
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作者 Xizi Song Ruixin Li +6 位作者 Xiaolei Chu Qi Li Ruihua Li Qingwen Li Kai-Yu Tong Xiaosong Gu Dong Ming 《Neural Regeneration Research》 SCIE CAS 2025年第10期2807-2822,共16页
Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes... Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target organs.This has led to restrictions on current therapeutic approaches.In this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target organs.After peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal cord.The nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury site.Corresponding damage to target organs can occur,including skeletal muscle atrophy and sensory receptor disruption.We then provide a brief review of the research advances in therapeutic approaches to peripheral nerve injury.The main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical exercise.However,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ pathway.Therefore,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery. 展开更多
关键词 central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach
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Electrophoretic Analysis of Isozymes and Discussion about Species Differentiation in Three Species of Genus Gymnocypris 被引量:15
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作者 陈毅峰 何德奎 陈宜瑜 《Zoological Research》 CAS CSCD 北大核心 2001年第1期9-19,共11页
By using the method of electrophoresis,three isozymes (lactate dehydrogenase,malate dehydrogenase and esterase) of three species of genus Gymnocypris were described and analyzed from North Tibet in this paper. The... By using the method of electrophoresis,three isozymes (lactate dehydrogenase,malate dehydrogenase and esterase) of three species of genus Gymnocypris were described and analyzed from North Tibet in this paper. The results showed that all three isozymes presented interspecific difference and distinct differentiation among individuals in the same population,and there was no electrophorectic difference between males and females. Analysis of relationships among three naked carps indicated a high degree of similarity between G. selincuoensis and G. cuoensis ,whereas low degree between G. selincuoensis and G. namensis . Furthermore,three isozymes presented expression of null alleles,and the duplicate genes of LDH A 2,LDH B 2,s MDH A 2 and m MDH B 2 also expressed in some individuals. Compared to other tetraploid fishes,three naked carps retained more functional duplicate genes and null alleles. This suggests fishes of genus Gymnocypris are at the early stage of evolution after polyploidization than that of fishes of Catostomidae,it directly related to the later time of schizothoracine fishes originate as well as severe environment. 展开更多
关键词 Naked carps ( Gymnocypris ) North Tibet Isozyme electrophoresis Duplicate gene Null allele species differentiation
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Risk Assessment and Analysis of Bursaphelenchus Species in the Coniferous Forest in Yuyao, Ningbo
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作者 郑炜 《Agricultural Science & Technology》 CAS 2017年第12期2513-2516,共4页
The method for pest risk analysis was used to make the potential risk analysis and assessment to the 8 Bursaphelenchus species found in the pines in Yuyao, Ningbao, and the corresponding risk management strategies wer... The method for pest risk analysis was used to make the potential risk analysis and assessment to the 8 Bursaphelenchus species found in the pines in Yuyao, Ningbao, and the corresponding risk management strategies were put forward. 展开更多
关键词 Risk analysis BURSAPHELENCHUS Beilun
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Fingerprint analysis of different Panax herbal species by HPLC-UV method 被引量:4
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作者 曾凤 王晓明 +2 位作者 杨敏 卢志强 果德安 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第4期277-281,共5页
Aim To establish a method for differentiating commercial samples of Panax species including notoginseng, cultivated ginseng (Chinese ginseng and Korean ginseng), wild ginseng, red ginseng, three types of American gi... Aim To establish a method for differentiating commercial samples of Panax species including notoginseng, cultivated ginseng (Chinese ginseng and Korean ginseng), wild ginseng, red ginseng, three types of American ginsengs, and one American ginseng preparation with their HPLC fingerprints for assnrning the quality of different commercial samples of Panax species. Methods HPLC-UV method was used to establish their fingerprints, Zorbax Extend C18 (250 mm×4.6 mm, 5 μm) was used as the analytical column, and acetonitrile/KH2PO4 aqueous solution was used as the mobile phase with gradient elution. Results The fingerprints of different commercial samples of Panax species varied in their holistic chromatograms and some specific constituents. Conclusion This method is reliable, reproducible and simple, It could be applied in the routine authentication of different commercial samples of Panax species 展开更多
关键词 GINSENG Panax species HPLC fingerprint
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Complete Mitochondrial Genome of the Red Fox (Vuples vuples) and Phylogenetic Analysis with Other Canid Species 被引量:4
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作者 钟华明 张洪海 +2 位作者 沙未来 张承德 陈玉才 《Zoological Research》 CAS CSCD 北大核心 2010年第2期122-130,共9页
The whole mitochondrial genome sequence of red fox (Vuples vuples) was determined. It had a total length of 16 723 bp. As in most mammal mitochondrial genome, it contained 13 protein coding genes, two ribosome RNA g... The whole mitochondrial genome sequence of red fox (Vuples vuples) was determined. It had a total length of 16 723 bp. As in most mammal mitochondrial genome, it contained 13 protein coding genes, two ribosome RNA genes, 22 transfer RNA genes and one control region. The base composition was 31.3% A, 26.1% C, 14.8% G and 27.8% T, respectively. The codon usage of red fox, arctic fox, gray wolf, domestic dog and coyote followed the same pattern except for an unusual ATT start codon, which initiates the NADH dehydrogenase subunit 3 gene in the red fox. A long tandem repeat rich in AC was found between conserved sequence block 1 and 2 in the control region. In order to confirm the phylogenetic relationships of red fox to other canids, phylogenetic trees were reconstructed by neighbor-joining and maximum parsimony methods using 12 concatenated heavy-strand protein-coding genes. The result indicated that arctic fox was the sister group of red fox and they both belong to the red fox-like clade in family Canidae, while gray wolf, domestic dog and coyote belong to wolf-like clade. The result was in accordance with existing phylogenetic results. 展开更多
关键词 Red fox Mitochondrial genome CANIDAE Phylogenetic analysis
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Species distribution of polymeric aluminium ferrum——timed complexation colorimetric analysis method of Al-Fe-Ferron 被引量:8
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作者 Hu, YY Tu, CQ Wu, HH 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第4期418-421,共4页
The effects of the calorimetric buffer solutions were investigated while the two colorimetric reactions of AI-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and t... The effects of the calorimetric buffer solutions were investigated while the two colorimetric reactions of AI-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and the pH of the solutions were also investigated. A timed complexatian colorimetric analysis method of Al-Fe-ferron in view of the total concentration of {AI + Fe} was then established to determine the species distribution of polymeric Al-Fe. The testing wavelength was recommended at 362 net and the testing pH value was 5. With a comparison of the ratios of n(Al)/n(Fe), the standard adsorption curves of the polymeric Al-Fe solutions were derived from the experimental results. Furthermore, the solutions' composition were carious in both the molar n(Al)/n(Fe) ratios, i.e. 0/0, 5/5, 9/1 and 0/10, and the concentrations associated with the total ( Al + Fe which ranged from 10(-5) to 10(-4) mol/L.. 展开更多
关键词 polymeric aluminum-ferrum species distribution timed complexation colarimetric analysis method Al-Fe-ferron
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Analysis of the Species Dominance & Dominant on the Karst Mountain Grassland Plant Community 被引量:4
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作者 张文 张建利 《Agricultural Science & Technology》 CAS 2011年第7期1020-1024,共5页
[Objective] The aim was to study the species,quantity and community traits of dominant plant in karst mountain grassland plant community so as to provide support for the vegetation restoration in karst mountain grassl... [Objective] The aim was to study the species,quantity and community traits of dominant plant in karst mountain grassland plant community so as to provide support for the vegetation restoration in karst mountain grassland.[Method] Standard plot sites investigation method was used study the quantity traits of different plant communities of different altitudes and slopes.[Result] The IV SDR4 were the highest in the all plot sites of plant community on the kasrt mountain grassland,but the IV SDR4 were showed a trend of decreasing with the increasing of the altitude.The dominant quantity was increasing with the altitude upward,so the altitude was the mostly factor for plant community construction.[Conclusion] Altitude was the main factor to influence the community structure of plant. 展开更多
关键词 KARST Grassland plant COMMUNITY species dominance DOMINANT
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Analysis on the indicator species and ecological groups of pelagic ostracods in the East China Sea 被引量:9
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作者 XU Zhaoli 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第6期83-93,共11页
Ecological adaptation and ecological groups of pelagic ostracods were examined in the East China Sea (23°30′-33°00′N, 118°30′ -128°00′E), in relation to temperature and salinity. The data we... Ecological adaptation and ecological groups of pelagic ostracods were examined in the East China Sea (23°30′-33°00′N, 118°30′ -128°00′E), in relation to temperature and salinity. The data were collected in four surveys conducted from 1997 to 2000. The density, yield density, or negative exponent models were used to determine the optimal temperature and salinity of water for the thriving growth of pelagic ostracods. Thereafter, ecological groups and potential distribution patterns of pelagic ostracods were determined based on the predicted parameters such as optimal temperature and salinity, consulting the geographic distribution. The analytical results indicate that, among the numerical dominant pelagic ostracods in the East China Sea (ECS), Euconchoecia aculeata, E. elongata, E. chierchiae, E. maimai, and Cypridina dentata, etc. are offshore subtropical water species. These species are widely distributed in the area, and they can be brought by the warm current to north offshore during spring and winter. The predicated optimal temperature (OT) and optimal salinity (OS) for Paraconchoecia decipiens, P. echinata, P. spini- fera, P. oblonga, Conchoecia magna and Porroeciaporrecta are all greater than 25℃ and 34 separately. These species are mainly distributed in the waters of the Kuroshio, the Taiwan Warm Current, and the Taiwan Strait, and therefore are designated as ocean- ic tropical water species. On the other hand, Pseudoconchoecia concerttrica is considered as offshore subtropical water species based on its geographical distribution although its OT is 19℃. The other species, though their OSs are approximately 34 and with OTs ranging from 20° to 25℃, are considered as offshore subtropical water species because they were found to be widely distributed from the South China Sea to the East China Sea. 展开更多
关键词 ZOOPLANKTON pelagic ostracods ECOTYPE temperature SALINITY East China Sea indicator species
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Population Viability Analysis of Gloydius shedaoensis from Northeastern China:A Contribution to the Assessment of the Conservation and Management Status of an Endangered Species 被引量:2
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作者 LIU Peng SUN Lixin +3 位作者 LI Jianli WANG Li ZHAO Wenge JIA Jingbo 《Asian Herpetological Research》 SCIE 2010年第1期48-56,共9页
Shedao pit-vipers(Gloydius shedaoensis) on Snake Island in the Liaoning Province, China, are among the most imperiled species in China. The isolated and unique populations are crucial in the recovery of this endangere... Shedao pit-vipers(Gloydius shedaoensis) on Snake Island in the Liaoning Province, China, are among the most imperiled species in China. The isolated and unique populations are crucial in the recovery of this endangered species by providing a way for conservation and management. Research based on the ecological simulation tools can evaluate alternative mitigation strategies in terms of their benefits to the populations, which are vital for informed decision-making. In this paper, using the program VORTEX 9.42, we developed a population viability analysis(PVA) for the Shedao pit-viper to:(1) address the extinction likelihood of the population;(2) simulate population dynamics under various environment events, and(3) evaluate the efficacy of current protection and management strategies. Overall, we found the population to be susceptible to the factors of catastrophic events, mortality and environment capacity. The population is recovering slowly at present on account of improvement of habitat and greater food availability. Under the current conditions, the probability of extinction in 100 years is approximately zero. These data coincide with the evidence that the wild population may be arriving at K. Our results strengthen the view that protection and management can create a pronounced effect on populations of this endangered species. 展开更多
关键词 Gloydius shedaoensis VORTEX simulation model sensitivity analysis model veracity test species conservation
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Multi-scale analysis on species diversity within a 40-ha old-growth temperate forest 被引量:2
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作者 Jie Gao Peng Zhang +1 位作者 Xing Zhang Yanhong Liu 《Plant Diversity》 SCIE CAS CSCD 2018年第2期45-49,共5页
In order to better explore the maintenance mechanisms of biodiversity, data collected from a 40-ha undisturbed Pinus forest were applied to the Individual Species-Area Relationship model(ISAR) to determine distributio... In order to better explore the maintenance mechanisms of biodiversity, data collected from a 40-ha undisturbed Pinus forest were applied to the Individual Species-Area Relationship model(ISAR) to determine distribution patterns for species richness. The ecological processes influencing species abundance distribution patterns were assessed by applying the same data set to five models: a LogNormal Model(LNM), a Broken Stick Model(BSM), a Zipf Model(ZM), a Niche Preemption Model(NPM), and a Neutral Model(NM). Each of the five models was used at six different sampling scales(10 m×10 m, 20 m×20 m, 40 m×40 m, 60 m×60 m, 80 m×80 m, and 100 m×100 m). Model outputs showed that:(1) Accumulators and neutral species strongly influenced species diversity, but the relative importance of the two types of species varied across spatial scales.(2) Distribution patterns of species abundance were best explained by the NPM at small scales(10 m-20 m), whereas the NM was the best fit model at large spatial scales.(3) Species richness and abundance distribution patterns appeared to be driven by similar ecological processes. At small scales, the niche theory could be applied to describe species richness and abundance, while at larger scales the neutral theory was more applicable. 展开更多
关键词 species richness species abundance Spatial scales Niche theory Neutral theory
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Analysis on the daily courses of water potential of nine woody species from Cerrado vegetation during wet season 被引量:5
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作者 张文辉 马瑞萍 《Journal of Forestry Research》 CAS CSCD 2000年第1期7-12,共6页
The water potential (Ψ) daily courses of 9 woody species from Cerrado vegetation in different weather conditions during wet season were observed and analyzed. The adjusting strategies of 9 species could be divided in... The water potential (Ψ) daily courses of 9 woody species from Cerrado vegetation in different weather conditions during wet season were observed and analyzed. The adjusting strategies of 9 species could be divided into 3 groups according to Cluster Analysis and based on the data observed on the January 18, March 20 and April 6. The Ψ values of the first group, which included 2 species, were maintained at the higher level consistently. The Ψ values of the second group, which included 5 species, were intermediate level. The Ψ values of the third group, which included 2 species, were kept in the lower level. The Ψ values of all species always kept pace with the weather condition, especially water condition. During the clear day only one Ψ value peak for all species occurred at midday (12∶30–13∶30). When the overcast or raining occurred for a short period, the fluctuation of Ψ values would appear after about 15–30 min responding to the change of weather condition. Even in the same group under the same external circumstance, there was a clear variation of the leaf Ψ values among different species, which showed that the strategy diversity for plant to balance water relation. From January to April, the Ψ values of 9 species reduced in response to the drought condition. The species with the lower values of water saturation deficiency at turgid loss point (W sdtlp) the osmotic potential at saturation (πsat), the osmotic potential at turgid lose point (πtip) or lower predawn water potential (Ψpd) usually had the lower Ψ values at midday. The mechanism of water balance controlled by many systems has been assumed. 展开更多
关键词 Wet season Water balance strategy Osmotic potential Water potential Woody species
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A New Species of Cupressinocladus from the Lower Cretaceous of Guyang Basin,Inner Mongolia,China and Cluster Analysis 被引量:1
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作者 JIN Peihong MAO Teng +5 位作者 DONG Junling WANG Zixi SUN Mingxuan XU Xiaohui DU Baoxia SUN Bainian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第4期1200-1214,共15页
Cupressinocladus Seward is a fossil genus of conifers and conifer fossils with reproductive organs are very rare. In general, it is difficult to understand the natural affinities with other conifers. In this paper, a ... Cupressinocladus Seward is a fossil genus of conifers and conifer fossils with reproductive organs are very rare. In general, it is difficult to understand the natural affinities with other conifers. In this paper, a new species, Cupressinocladus guyangensis P.H. Jin et B.N. Sun sp. nov., is reported based on branches with immature female cones from the Lower Cretaceous Guyang Formation of the Guyang Basin in Inner Mongolia, northern China. The foliage shoots are decussate. Leaves are decussate, imbricate, scale-like, weakly dimorphic, and bear longitudinal glands on the abaxial view. Stomata complexes are haplocheilic, monocyclic, irregularly arranged, and spread along the leaf margin. Immature female cones are subglobose with 6-8 cone scales, and three subglobose ovules arranged in a row at the base of the cone scales. Moreover, we performed cluster analysis using a statistics and machine learning toolbox for 23 fossils and extant species based on 16 morphological characters. The result implies that the new species bears a close resemblance to the extant Cupressusfunebris Endl. and might have nearest systematic affinities to it. 展开更多
关键词 Cupressinocladus Immature female cone Lower Cretaceous Cluster analysis New species
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Comparative analysis of flower-meristem-identity gene APETALA2 (AP2) codon in different plant species 被引量:5
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作者 WU Yan-qing LI Zhi-yuan +1 位作者 ZHAO Da-qiu TAO Jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第4期867-877,共11页
The flower-meristem-identity gene APETALA2(AP2), one of class-A genes, is involved in the establishment of the floral meristem and the forming of sepals and petals. Codon usage bias(CUB) identifies differences among s... The flower-meristem-identity gene APETALA2(AP2), one of class-A genes, is involved in the establishment of the floral meristem and the forming of sepals and petals. Codon usage bias(CUB) identifies differences among species, meanwhile dynamic analysis of base composition can identify the molecular mechanisms and evolutionary relationships of a specific gene. In this study, eight coding sequences(CDS) of AP2 gene were selected from different plant species using the Gen Bank database. Their nucleotide composition(GC content), genetic index, relative synonymous codon usage(RSCU) and relative codon usage bias(RCUB) were calculated with R Software to compare codon bias and base composition dynamics of AP2 gene codon usage patterns in different plant species. The results showed that the usage of AP2 gene codons from different plant species were influened by GC bias, especially GC3 s. Overall, base composition analysis indicated that the usage frequency of codon AT in the gene coding sequence was higher than GC among AP2 gene CDS from different plant species. Furthermore, most AP2 gene CDSs ended with AT; AGA, GCU and UGU had relatively high RSCU values as the most dominant codon; the usage characteristic of the AP2 gene codon in Malus domestica was similar to that of Vitis vinifera; Paeonia lactiflora was similar to Paeonia suffruticosa and Solanum lycopersicum was similar to Petunia×hybrida. There was a moderate preference in the usage of AP2 gene codon among different plant species from relatively low frequency of optimal codon(Fop) values and high effective number of codons(ENC) value. This study has revealed the usage characteristics of the AP2 gene codon from the comparision of AP2 gene codon preference and base dynamics in different plant species and provide a platform for further study towards transgenic engineering and codon optimization. 展开更多
关键词 APETALA2(AP2) species codon usage bias(CUB) base composition dynamics
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Analysis of Energetic Species Caused by Contact Glow Discharge Electrolysis in Aqueous Solution 被引量:1
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作者 高锦章 王爱香 +5 位作者 付燕 吴建林 马东平 郭晓 李岩 杨武 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第1期30-38,共9页
Contact glow discharge electrolysis is a non-Faradaic electrochemical process with an abnormal relationship between the current and voltage. Hydroxyl radicals, hydrogen radicals and hydrogen peroxide can be produced u... Contact glow discharge electrolysis is a non-Faradaic electrochemical process with an abnormal relationship between the current and voltage. Hydroxyl radicals, hydrogen radicals and hydrogen peroxide can be produced under the glow discharge, which are often used to degrade organic contaminants in aqueous solution. In this study, with 4-nitrophenol taken as an example of contaminants and tert-butanol as a scavenger of hydroxyl radicals, the role of energetic species in degrading organic compounds was examined in detail. Moreover, the effects of the applied voltage, solution conductivity and pH on the formation of three energetic species were also observed. The formation rate constants of the three energetic species were calculated based on the experimental data. 展开更多
关键词 contact glow discharge electrolysis analysis energetic species formation rate constant
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Novel Species Including Mycobacterium fukienense sp. Is Found from Tuberculosis Patients in Fujian Province, China, Using Phylogenetic Analysis of Mycobacterium chelonae/abscessus Complex 被引量:3
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作者 ZHANG Yuan Yuan LI Yan Bing +4 位作者 HUANG Ming Xiang ZHAO Xiu Qin ZHANG Li Shui LIU Wen En WAN Kang Lin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第11期894-901,共8页
Objective To identify the novel species ‘Mycobacterium fukienense' sp. nov of Mycobacterium chelonoe/abscessus complex from tuberculosis patients in Fujian Province, China. Methods Five of 27 clinical Mycobucterium ... Objective To identify the novel species ‘Mycobacterium fukienense' sp. nov of Mycobacterium chelonoe/abscessus complex from tuberculosis patients in Fujian Province, China. Methods Five of 27 clinical Mycobucterium isolates (CIs) were previously identified as M. chelonoe/obscessus complex by sequencing the hsp65, rpoB, 165-235 rRNA internal transcribed spacer region (its), recA and sodA house-keeping genes commonly used to describe the molecular characteristics of Mycobocterium. Clinical Mycobecterium isolates were classified according to the gene sequence using a clustering analysis program. Sequence similarity within clusters and diversity between clusters were analyzed. Results The 5 isolates were identified with distinct sequences exhibiting 99.8% homology in the hsp65 gene. However, a complete lack of homology was observed among the sequences of the rpoB, 165-235 rRNA internal tronscribed spacer region (its), sodA, and recA genes as compared with the M. obscessus. Furthermore, no match for rpoB, sodA, and recA genes was identified among the published sequences. Conclusion The novel species, Mycobacterium fukienense, is identified from tuberculosis patients in Fujian Province, China, which does not belong to any existing subspecies of M. cheloneo/abscessus complex. 展开更多
关键词 species identification Mycobacterium chelonae/abscessus complex Mycobacterium fukienense
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Analysis of the Germplasm Resources and Genetic Relationships Among Hybrid Cymbidium Cultivars and Native Species with RAPD Markers 被引量:8
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作者 LI Dong-mei YE Qing-sheng ZHU Gen-fa 《Agricultural Sciences in China》 CAS CSCD 2007年第8期922-929,共8页
The random amplified polymorphic DNA (RAPD) marker was assessed to detect the genetic relationships among 48 hybrid Cymbidium cultivars from Japan, Korea, China, and USA, and 2 species of native Cymbidium. Twenty pr... The random amplified polymorphic DNA (RAPD) marker was assessed to detect the genetic relationships among 48 hybrid Cymbidium cultivars from Japan, Korea, China, and USA, and 2 species of native Cymbidium. Twenty primers were screened from 100 random decamer primers, and a total of 258 DNA bands were amplified, 253 of which (98.1%) were polymorphic. The average number of polymorphic DNA bands amplified by each primer was 12.6. All cultivars were distinguishable when a number of primers were considered. Genetic similarities among the cultivars and species were estimated based on the amount of band sharing ranging from 0.364-0.817 with an average of 0.581. According to the data, a dendrogram of genetic relationship, which was constructed using the UPGMA method, showed that all the tested cultivars and native species were classified into five cluster groups with the similarity coefficient of 0.592. It revealed that the genetic relationships among tested accessions were to some extent related with their origin, flower colour, branch type, and genealogy. It further indicated that the RAPD technique is a useful tool for studying the genetic relationships among hybrid Cymbidium cultivars. 展开更多
关键词 CYMBIDIUM genetic relationship RAPD markers cluster analysis
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Species analysis methods for hydrolysis polymerization of aluminum 被引量:3
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作者 Feng Li, Luan Zhao kun, Tang Hong xiao Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第1期33-38,共6页
Al Ferron timed complex colorimetric method (AFM) and 27 Al NMR spectroscopy method(ANM) were discussed. For the former, the different colorimetric reagent preparation methods' results indicate that the... Al Ferron timed complex colorimetric method (AFM) and 27 Al NMR spectroscopy method(ANM) were discussed. For the former, the different colorimetric reagent preparation methods' results indicate that there are some differences beteween them, and the combined method can be used as a simplified procedure. For the latter, the small tube method is more accurate. Eventually, the Al 13 (ANM) was compared to the Al b (AFM). 展开更多
关键词 hydrolysis polymerization species of Al 27 Al NMR Al Ferron timed complex colorimetric method.
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SSR Analysis on Diversity of AA Genome Oryza Species in the Southeast and South Asia 被引量:2
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作者 Jian-zhen LU Xiao-li ZHANG +6 位作者 Hai-gang WANG Xiao-ping YUAN Qun XU Yi-ping WANG Han-yong YU Sheng-xiang TANG Xing-hua WEI 《Rice science》 SCIE 2008年第4期289-294,共6页
To investigate genetic diversities among the AA genome Oryza species in the Southeast and South Asia, a total of 428 accessions of the AA genome Oryza species were genotyped using 36 simple sequence repeats (SSR) mark... To investigate genetic diversities among the AA genome Oryza species in the Southeast and South Asia, a total of 428 accessions of the AA genome Oryza species were genotyped using 36 simple sequence repeats (SSR) markers distributed throughout the rice genome. All of the 36 SSR markers generated polymorphic bands, revealing 100% polymorphism. The number of alleles per locus ranged from 3 to 17 with the mean of 8.6. The Nei's genetic diversity index (He) ranged from 0.337 at RM455 to 0.865 at RM169 with an average value of 0.650. The genetic diversity of the AA genome Oryza species in the Southeast Asia was obviously higher than that in the South Asia. Among the detected Oryza species in the South and Southeast Asia, O. rufipogon showed the highest genetic diversity. Meanwhile, a higher genetic differentiation (Fst) was found among the detected Oryza species in the Southeast Asia than in the South Asia. The Fst value between O. nivara and O. sativa was the highest. The results from the number of specific alleles, specific loci, and allele frequency confirmed the greater genetic variation among the detected species. In addition, the specific allele in RM161 displayed higher frequency (0.193), suggesting its important function in identifying Oryza species of AA genome. 展开更多
关键词 GENOME Oryza species simple sequence repeat genetic diversity South Asia Southeast Asia
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