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如何在课堂教学中保持学生口译的积极性和可持续性——《英汉口译》网培课程学习体会 被引量:1
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作者 贾云红 《科技创新导报》 2013年第21期142-142,共1页
该文结合四川大学外国语学院副院长、博士生导师任文教授的"3P"模式,提出了在口译教学中应"分阶段(Phrased)"教学、"强训练(Practiced)"教学和"多花样(Pluralized)"教学,从而在课堂教学中保持... 该文结合四川大学外国语学院副院长、博士生导师任文教授的"3P"模式,提出了在口译教学中应"分阶段(Phrased)"教学、"强训练(Practiced)"教学和"多花样(Pluralized)"教学,从而在课堂教学中保持学生口译的积极性和可持续性。 展开更多
关键词 口译教学 分阶段 强训练 多花样
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Genetic Diversity in Cultivated Groundnut Based on SSR Markers 被引量:6
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作者 唐荣华 高国庆 +7 位作者 贺梁琼 韩柱强 单世华 钟瑞春 周翠球 蒋菁 李杨瑞 庄伟建 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第5期449-459,共11页
Peanut (Arachis hypogaea L.) is an important source crop for edible oil and protein. It is important to identify the genetic diversity of peanut genetic resources for cultivar development and evaluation of peanut ac... Peanut (Arachis hypogaea L.) is an important source crop for edible oil and protein. It is important to identify the genetic diversity of peanut genetic resources for cultivar development and evaluation of peanut accessions. Thirty-four SSR markers were used to assess the genetic variation of four sets of twenty-four accessions each from the four botanical varieties of the cultivated peanut. Among the tested accessions, ten to sixteen pairs of SSR primers showed polymorphisms. The maximum differentiation index, which was defined as the degree of genetic differentiation, was as high as 0.992 in the tested accessions. Each accession could be discriminated by a specific set of polymorphic SSR primers, and the intra-variety genetic distance was determined among accessions, with an average of 0.59 in var. fastigiata, 0.46 in var. hypogaea, 0.38 in var. vulgaris, and 0.17 in var. hirsuta. Dendrogrames based on genetic distances were constructed for the four botanical varieties, which revealed the existence of different clusters. It was concluded that there was abundant intra-variety SSR polymorphism, and with more and more SSR markers being developed, the intrinsic genetic diversity would be detected and the development of genetic map and marker-assisted selection for cultivated peanut would be feasible. 展开更多
关键词 Arachis hypogaea SSR genetic diversity differentiation index
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糯玉米巧栽培优质高产
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作者 张路 李强 《中国农垦》 2001年第4期22-22,共1页
随着人们生活水平的提高,炒嫩玉米粒、煮烤糯玉米青穗等成了人们喜欢的副食品.栽培糯玉米,技术上应注意如下几点:
关键词 糯玉米 栽培技术 多花样播种 良种选择 隔离种植 合理密植 肥料 虫害防治 采收时间
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Diversity and Classification of Soil Fungi in Main Peanut Producing Areas of China 被引量:2
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作者 董李学 张谊 +3 位作者 杜瑞焕 姚彦坡 齐彪 项爱丽 《Agricultural Science & Technology》 CAS 2017年第11期2067-2069,2170,共4页
In the study, 1 255 fungal strains were isolated from 105 peanut soil samples collected from 15 counties in 10 provinces of China. These fungi were identified to 21 genera, using the method of microscopical observatio... In the study, 1 255 fungal strains were isolated from 105 peanut soil samples collected from 15 counties in 10 provinces of China. These fungi were identified to 21 genera, using the method of microscopical observation according to morphology. And 2 genera were members of oomycetes, 3 genera of ascomycota and 16 genera of mitosporic fungi. In these soil samples, the dominant species were Penicillium, Trichoderma and Fusarium, accounting for 28.89%, 14.16% and 8.64%, respectively. 展开更多
关键词 PEANUT SOIL FUNGI DIVERSITY IDENTIFICATION
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Contrasting patterns of free-living bacterioplankton diversity in macrophyte-dominated versus phytoplankton blooming regimes in Dianchi Lake,a shallow lake in China 被引量:3
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作者 王毓菁 李化炳 +1 位作者 邢鹏 吴庆龙 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第2期336-349,共14页
Freshwater shallow lakes typically exhibit two alternative stable states under certain nutrient loadings:macrophyte-dominated and phytoplankton-dominated water regimes.An ecosystem regime shift from macrophytes to phy... Freshwater shallow lakes typically exhibit two alternative stable states under certain nutrient loadings:macrophyte-dominated and phytoplankton-dominated water regimes.An ecosystem regime shift from macrophytes to phytoplankton blooming typically reduces the number of species of invertebrates and fishes and results in the homogenization of communities in freshwater lakes.We investigated how microbial biodiversity has responded to a shift of the ecosystem regime in Dianchi Lake,which was previously fully covered with submerged macrophytes but currently harbors both ecological states.We observed marked divergence in the diversity and community composition of bacterioplankton between the two regimes.Although species richness,estimated as the number of operational taxonomic units and phylogenetic diversity(PD),was higher in the phytoplankton dominated ecosystem after this shift,the dissimilarity of bacterioplankton community across space decreased.This decrease in beta diversity was accompanied by loss of planktonic bacteria unique to the macrophyte-dominated ecosystem.Mantel tests between bacterioplankton community distances and Euclidian distance of environmental parameters indicated that this reduced bacterial community differentiation primarily reflected the loss of environmental niches,particularly in the macrophyte regime.The loss of this small-scale heterogeneity in bacterial communities should be considered when assessing long-term biodiversity changes in response to ecosystem regime conversions in freshwater lakes. 展开更多
关键词 bacterioplankton biodiversity regime shift MACROPHYTE PHYTOPLANKTON
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Phenotypic Characterization of Indigenous Iraqi Sinorhizobium meliloti Isolates for Abiotic Stress Performance 被引量:1
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作者 Rana A. Hameed Nidhal N. Hussain Abedaljasim M. Aljibouri 《Journal of Life Sciences》 2014年第1期1-9,共9页
Alfalfa (Medicago sativa L.) is being grown in harsh environment in Iraq and is mostly subjected to abiotic stresses such as drought, salinity, pH and temperature. Both alfalfa and its nitrogen fixing symbiotic bact... Alfalfa (Medicago sativa L.) is being grown in harsh environment in Iraq and is mostly subjected to abiotic stresses such as drought, salinity, pH and temperature. Both alfalfa and its nitrogen fixing symbiotic bacteria Sinorhizobium meliloti are affected by these environmental stresses. Enhancing nitrogen fixation biologically could be achieved through selection of tolerant strains of S. meliloti to these environmental stresses and inoculating them to the crop, also growing tolerant cultivars. This study examines phenotypic diversity for tolerance to drought, salinity, temperature and pH. Sixty isolates sampled from different areas of Iraq. The results revealed high degree of phenotypic diversity in Sinorhizobium populations. Furthermore, the isolates which showed tolerance to drought stress also showed tolerance to salinity and high degree of temperature, indicating direct relationship between three physiological path ways. Also 58.3% of drought tolerant isolates were alkaline tolerant they tolerated up to pH 9, point to say almost all drought tolerant isolates in this study illustrated strong + positive reaction to catalase enzyme. And 91.6% themes were negative for Gelatinase enzyme test. While only 50% of drought sensitive isolates were negative for drought sensitive isolates could grow at high temperature (42 ℃). 展开更多
关键词 Sinorhizobium meliloti PHENOTYPIC abiotic stresses.
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Diversity and Evolution of Inflorescences in Celastrales
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作者 Ivan A. Savinov 《Journal of Life Sciences》 2013年第2期145-152,共8页
Inflorescences structures in context of their evolution have been conducted for 60 genera and 170 species of Celastrales (according to APG (Angiosperm Phylogeny Group) III 2009, almost 60% of genera and 15% of spec... Inflorescences structures in context of their evolution have been conducted for 60 genera and 170 species of Celastrales (according to APG (Angiosperm Phylogeny Group) III 2009, almost 60% of genera and 15% of species from this taxon of the world flora). There are two big groups of inflorescences in Celastrales-intercalary (more often) and terminal. For many genera of Celastrales both types of inflorescences can be observed, although the frequency of their occurrence varies. There is an important difference between two types of inflorescences: character of completion of the main axis (the terminal flower present or absent). Flower opening can be in basipetal (Celastraceae, Brexia) or acropetal (Stackhousiaceae) order. Partial inflorescence types included: simple, compound or umbrellate dichasia, spike, raceme, thyrse. Simple flowers of Parnassia are large, nested on long reproductive shoots, emerging from a rosette, with amplexicaule leaf. 展开更多
关键词 Celastrales CELASTRACEAE Brexia Parnassia Stackhousiaceae INFLORESCENCES structure and development ofinflorescences molecular data.
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Exploring genetic diversity in Northeastern Sika deer population (Cervus nippon hortulorum) by AFLP molecular markers
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作者 CAI Zhi-hua JIANG De-mei +3 位作者 LUO An-cai TAO Hong-mei HAN Li WEN Xin-fu 《Journal of Life Sciences》 2009年第9期54-61,共8页
The genetic diversity of 27 different Cervus nippon hortulorum was studied to provide theoretical evidence for their identification and utilization. The genomie DNA of 27 different Cereus nippon hortulorum were analyz... The genetic diversity of 27 different Cervus nippon hortulorum was studied to provide theoretical evidence for their identification and utilization. The genomie DNA of 27 different Cereus nippon hortulorum were analyzed by amplified fragment length polymorphism (AFLP). 11,443 bands associated with genetic polymorphism among total 15,169 bands were obtained with 9 kinds of primer pairs and restriction endonuclease EcoRI/Msel, percentage of polymorphie band was 78.43%, 1,271 polymorphic locus were shown per primer pair. The AFLP data showed that average genetic similarity was 0.7841 (0.6809-0.8648). 27 samples were classified into Group I and Group II with cluster analysis, and Group II was divided into five subgroups. The result of AFLP and cluster analysis concluded that there was high genetic variation, which associated with orientated artificial breed selection and breeding in the population. Genetic similarity of Group II-4 was the highest, more than 0.82, while genetic distance in this group was the shortest, from 0.1354 to 0.1563, which was coordinated with breeding record. All these showed that there was great genetic polymorphism among the deer population. The results laid the foundation for main quantitative trait locus (QTLs) of Cervus nippon hortulorum. 展开更多
关键词 Cervus nippon hortulorum population genetic structure AFLP genetic polymorphism
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Genetic diversity and population structure of a Sichuan sika deer(Cervus sichuanicus) population in Tiebu Nature Reserve based on microsatellite variation 被引量:1
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作者 Ya HE Zheng-Huan WANG Xiao-Ming WANG 《Zoological Research》 CAS CSCD 北大核心 2014年第6期528-536,共9页
Cervus sichuanicus is a species of sika deer (Cervus nippon Group). To date, research has mainly focused on quantity surveying and behavior studies, with genetic information on this species currently deficient. To p... Cervus sichuanicus is a species of sika deer (Cervus nippon Group). To date, research has mainly focused on quantity surveying and behavior studies, with genetic information on this species currently deficient. To provide scientific evidence to assist in the protection of this species, we collected Sichuan sika deer fecal samples from the Sichuan Tiebu Nature Reserve (TNR) and extracted DNA from those samples. Microsatellite loci of bovine were used for PCR amplification. After GeneScan, the genotype data were used to analyze the genetic diversity and population structure of the Sichuan sika deer in TNR. Results showed that the average expected heterozygosity of the Sichuan sika deer population in TNR was 0.562, equivalent to the average expected heterozygosity of endangered animals, such as Procapra przewalsldi. Furthermore, 8 of 9 microsatellite loci significantly deviated from the Hardy-Weinberg equilibrium and two groups existed within the Sichuan sika deer TNR population. This genetic structure may be caused by a group of Manchurian sika deer (Cervus hortulorum) released in TNR. 展开更多
关键词 Sichuan sika deer MICROSATELLITE Genetic diversity Population structure
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Ophrys insectifera L.—Update of the Status of a Critically Endangered Orchid in Bulgaria
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作者 Andrey Popatanasov 《Journal of Life Sciences》 2018年第2期83-91,共9页
Aim: Ophrys insectTfera L. due to its peculiar biology and environmental requirements is among the most threatened and endangered vascular plants in Bulgaria. On the territory of Bulgaria the species fulfills the IUC... Aim: Ophrys insectTfera L. due to its peculiar biology and environmental requirements is among the most threatened and endangered vascular plants in Bulgaria. On the territory of Bulgaria the species fulfills the IUCN criteria for critically endangered [CR C2a(i); D] and is included also in the Red Data Book of Republic Bulgaria and Biodiversity Act. The present study aimed to explore and evaluate the status of its populations and their threats. Materials and methods: Exploration mad monitoring of the populations of the critically endangered orchid O. insectifera in Bulgaria was done from 2012 till 2017. The shoot count and some morphometxic parameters were recorded for evaluation of their distribution and population dynamics. Results and discussion: At one location Ophrys insectifera can be considered extinct. However two new locations were found so the total number of known locations is increased. Approximately over 50% of the occupied territories fall outside protected sites and many of the habitats axe endangered by anthropogenic or other factors. At all of the known locations there are less than 50 shoots per place. These facts put a high stress on the perspectives of their populations' survival in Bulgaria. 展开更多
关键词 Ophrys insectifera fly orchid bioconservation CONSERVATION orchids.
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Diversity of Mesozoic tin-bearing granites in the Nanling and adjacent regions,South China:Distinctive mineralogical patterns 被引量:15
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作者 WANG RuCheng XIE Lei +2 位作者 LU JianJun ZHU JinChu CHEN Jun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第11期1909-1919,共11页
The Nanling and adjacent regions of South China host a series of tin deposits related to Mesozoic granites with diverse petrological characteristics. The rocks are amphibole-bearing biotite granites, or (topaz-) alb... The Nanling and adjacent regions of South China host a series of tin deposits related to Mesozoic granites with diverse petrological characteristics. The rocks are amphibole-bearing biotite granites, or (topaz-) albite-lepidolite (zinnwaldite) granites, and geochemically correspond to mealuminous and peraluminous types, respectively. Mineralogical studies demonstrate highly distinctive and critical patterns for each type of granites. In mealuminous tin granites amphibole, biotite and perthite are the typical rock-forming mineral association; titanite and magnetite are typical accessory minerals, indicating highjO2 magmatic conditions; cassiterite, biotite and titanite are the principal Sn-bearing minerals; and pure cassiterite has low trace-element contents. However, in peraluminous tin granites zirmwaldite-lepidolite, K-feldspar and albite are typical rock-forming minerals; topaz is a common accessory phase, indicative of high peraluminity of this type of granites; cassiterite is present as a uniquely important tin mineral, typically rich in Nb and Ta. Mineralogical distinction between the two types of tin granites is largely controlled by redox state, volatile content and differentiation of magmatic melts. In oxidized metaluminous granitic melts, Sn4+ is readily concentrated in Ti-bearing rock-forming and accessory minerals. Such Sn-bearing minerals are typical of oxidized tin granites, and are enriched in granites at the late fractionation stage. In relatively reduced peraluminous granitic melts, Sn2+ is not readily incorporated into rock-forming and accessory minerals, except for cassiterite at fractionation stage of granite magma, which serves as an indicator of tin mineralization associated with this type of granites. The nature of magma and the geochemical behavior of tin in the two types of granites thus result in the formation of different types of tin deposits. Metaluminous granites host disseminated tin mineralization, and are locally related to deposits of the chlorite quartz-vein, greisen, and skarn types. Greisen, skarn, and quartz-vein tin deposits can occur related to peraluminous granites, but disseminated mineralization of cassiterite is more typical. 展开更多
关键词 Metaluminous tin granites Peraluminous granites Mineral assemblages Mineralogical indication of mineralization Nanling and adjacent regions
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Reversible algorithm of simulating multivariate densities with multi-hump 被引量:1
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作者 龚光鲁 钱敏平 解军 《Science China Mathematics》 SCIE 2001年第3期357-364,共8页
To simulate a multivariate density with multi_hump, Markov chainMonte Carlo method encounters the obstacle of escaping from one hump to another, since it usually takes extraordinately long time and then becomes practi... To simulate a multivariate density with multi_hump, Markov chainMonte Carlo method encounters the obstacle of escaping from one hump to another, since it usually takes extraordinately long time and then becomes practically impossible to perform. To overcome these difficulties, a reversible scheme to generate a Markov chain, in terms of which the simulated density may be successful in rather general cases of practically avoiding being trapped in local humps, was suggested. 展开更多
关键词 Markov chain Monte Carlo simulation Gibbs sampler multi-hump reversible Markov chain
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