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101.
马毓泉 《中国科学院研究生院学报》1951,1(1):5-19
Gentiana was originally proposed by Tournefort in 1700. Linnaeus adopted this generic name in his “Genera Plantarum” published in 1737. He divided the genus into seven groups on the basis of different shapes of corolla and forms of floral appendages. In his “Species Plantarum” he reorganized them into three artificial ones. Forty years later, Moench established a new genus, Gentianella under which he described G. tetrandra as the type of his new genus. In the view of identity of Gentianella tetrandra with Gentiana campestris L., it is evident that Gentianella represents only some plants formerly included in Gentiana at Linnaeus time. In 1796, Froelich’s monograph on Gentiana appeared. In his work four sections were represented and one of them was Crossopetalum. In 1845, Grisebach also published a monograph of Gentianaceae and recorded fifteen sections of which Amarella and Imaicola are two of his seven proposed ones. In 1888, Huxley studied the floral structure of Gentianaceae in relation with pollination mechanism and, accordingly, divided the family into two main groups, one with epipetalous glands, the other with glands at the base of the ovary. In each group, four types of flowers were found. He concluded that Gentiana was a complex genus on account of presence of four different types of flowers in this group, and suggested that many species of the genus should be separated out to form some smaller generic categories. Six years after, Kusnezow in his monograph divided Gentiana into two subgenera Eugentiana and Gentianella. In his system, subgenus Eugentiana consists of ten sections and the Gentianella, seven. He contributed much to the systematic treatment of Eugnetiana but little to that of Gentianella. He maintained the genus Gentiana in a broad sense. With increased knowledge of this group in the last thirty years, a number of botanists were able to make a clearer delimitation of true Gentiana and its allies and treated them in more natural way. Moench’s genus Gentianella was rerised. In 1936, H. Smith separated Megacodon from Gentianella as a genus. In the present paper, the writer suggests a generic name Gentianopsis for the section Crossopetalum in the same Genus.
This new genus is characterized by (1) its large and somewhat flattened ellipsoidal flower bud, (2) two dissimilar pairs of calyx lobes which are distichously imbricate in aestivation, (3) four triangular, ciflated intracalyx membranes at the base of and alternate with the calyx lobes, (4) distinct gynophore and (5) enlarged stigma. While in typical Gentianella represented by section Amarella, the flower buds are small and terete, a laciniate corona is usually present, and the calyx-lobes are leafy, lanceolate, imbricate, and not provided with intracalyx membrane.
Besides the morphological characters mentioned above, the anatomical structure of
the floral parts is also a significant generic criterion. In Gentianopsis, eight vascular
bundles are present in calyx, representing four dorsals and four fused ventrals. In each
corolla-lobe there are five bundles. In the body of ovary six bundles are present. The
ovule bearing surface is extensive covering nearly to entire surface of the ovary wall with
the exception of a narrow longitudinal zone along the dorsal bundle. In Gentianella,
calyx bundles are three in each lobe, without fusion of the ventrals. In each corolla-
lobe, the bundles are three instead of five as in Gentianopsis but the lateral ones branch
once dichotomously after entering the base of corolla. In the body of ovary only four
main bundles are present due to the fusion of smaller ventral ones. The placentation
is confined to the region of the ventral bundles.
Phylogenetically Gentianopsis and Gentianella may be regarded as closely reIated
and may represent branches of a common line with Gentianopsis standing at a lower
level, Gentianella being more advanced. In Gentianella the number of bundles in the
corolla segments and ovary wall are reduced by partial or complete fusion and the
distribution of ovules is confined only to the region of the ventral bundles. However,
in the calyx of Gentianopsis there is fusion of ventral bundles, whereas the correspound-
ing bundles in the Gentianella remain separate. The Gentianopsis-Gentianella line on
the one hand and the Gentiana line on the other may come again from a common
acestral stock. Gentiana possesses only three bundles in each corolla-lobe. A variety
of plicate between corolla lobes except in case of Gentiana lutea and intracalyx membrane
above the throat of calyx-tube are also the common structures in Gentiana. Thus the
pollination mechanism is highly specialized in the genus. As far as we know, in
Gentiana the glandular appendages usually exist at the base of ovary. If those nectarial
processes are correctly interpreted as the representatives of staminodes, gentiana would,
undoubtedly, be derived from an ancestral form with hypogynous diplostemonous
androecium, and bears no direct relationship to Gentianopsis or Gentianella in which the
glands are epipetalous. It may be reasonable to conclude the Gentiana and Gentianopsis-
Gentianella line are two parallel derivatives from a common ancestor which has the
floral characters of two series of hypogynous stamens. Gentianopsis and Gentianella may
represent branches of a common line with Gentianopsis standing at a lower level,
Gentianella being more advanced. Their relations may be diagrammed below:
Gentianopsis
Gentianella
Common ancestor
Gentiana
This new genus consists of fourteen species and two varieties in the world. Onlyeight species and two varieties are represented in China. They are G. barbara, G. barbatavar. sinensis, G. grandis, G. scabromanginata, G. paludosa, G. nana, G. longistyla,G. lutea, G. contorta, and G. contorta var. Wui. The species of present genus occur in the alpine regions of North Hemisphere. InChina t,hey are distributed in Kokonor, Kansu, Shensi, Shansi, Chahar, Hopei, Manchuria,Hupeh, Szechuan, Sikang, Tibet, and Yunnan. G. Yabei (Takeda et Hara) is foundin Japan, G. detonsa (Bott&) in North Europe, G. ciliata (Linn.) in South Europe,G. crinita (Froel.) G. procera (Holm.) and G. degans (A. Nels) in North America.G. barbata is the most widespreading species and reported in Sibiria and China.G. contorta (Royle) is a common plant in Himalayan mountaineous range, China andNorth part of India. The species and varieties cited in this paper are as follows:
t. Gentianopsis barbata (Froel.) comb. nov.
la. Gentianopsis barbata (Froel.) var. sinensis, var. nov.
2. Gentian opsis grandis (H. Sm.) comb. nov.
3. Gentianopsis scabromarginata (H. Sm.) comb. nov.
4. Gcntianopsis paludosa (Munro) comb. nov.
5. Gentianopsis nana sp. nov.
6. Gentianopsis longistyla, sp. nov.
7. Gentianopsis lutea, sp. nov. 相似文献
102.
Jia-Qi Fan Xue-Qing Yu Fang-Jun Cheng Heng Wang Ruifeng Wang Xiaobing Ma Xiao-Peng Hu Ding Zhang Xu-Cun Ma Qi-Kun Xue Can-Li Song 《国家科学评论(英文版)》2022,9(4)
The microscopic understanding of high-temperature superconductivity in cuprates has been hindered by the apparent complexity of crystal structures in these materials. We used scanning tunneling microscopy and spectroscopy to study the electron-doped copper oxide compound Sr1−xNdxCuO2, which has only bare cations separating the CuO2 planes and thus the simplest infinite-layer structure of all cuprate superconductors. Tunneling conductance spectra of the major CuO2 planes in the superconducting state revealed direct evidence for a nodeless pairing gap, regardless of variation of its magnitude with the local doping of trivalent neodymium. Furthermore, three distinct bosonic modes are observed as multiple peak-dip-hump features outside the superconducting gaps and their respective energies depend little on the spatially varying gaps. As well as the bosonic modes, with energies identical to those of the external, bending and stretching phonons of copper oxides, our findings reveal the origin of the bosonic modes in lattice vibrations rather than spin excitations. 相似文献
103.
Fei Xin Zheng Zhu Sitong Chen Huan Chen Xiaoqing Hu Xiao Ma Kun Liang Yang Liu Lijuan Wang Yujun Cai Ang Chen Yan Tang 《运动与健康科学(英文)》2022,11(3):358
PurposeThis study aimed to describe the national prevalence of Chinese children and adolescents who met the World Health Organization muscle-strengthening exercise (MSE) recommendations and identify correlates of meeting the MSE recommendations.MethodsCross-sectional data from the 2019 Physical Activity and Fitness in China—The Youth Study, a nationally representative sample of Chinese children and adolescents (n = 80,413; mean age = 13.7 years; 53.9% girls) and their parents, were analyzed. Children and adolescents who reported engaging ≥3 days (up to 7 days) of MSE per week were classified as meeting the MSE recommendations. MSE, demographics, lifestyle behaviors (sport participation, moderate-to-vigorous physical activity, screen time, and sleep duration), exercise intention, peer and parental support, and parental MSE participation were assessed through self-reports. Logistic regression models were used to determine the correlates of meeting the MSE recommendations. The analyses were completed in 2020.ResultsOverall, 39.3% of children and adolescents met the MSE recommendations. Girls, 10th–12th graders, minorities, those from lower income households and those from families with lower parental education were less likely to meet the MSE recommendations. Children and adolescents who were proficient in ≥2 sports were more likely to meet the MSE recommendations (adjusted odds ratio (aOR) = 1.44, 95% confidence interval (95%CI): 1.26–1.65), as were those with more moderate-to-vigorous physical activity (aOR = 1.57, 95%CI: 1.53–1.61). Additionally, children and adolescents with high exercise intention (aOR = 1.60, 95%CI: 1.51–1.69), those whose parents met the adult MSE recommendations (aOR = 1.46, 95%CI: 1.40–1.52), and those who received high peer (aOR = 1.27, 95%CI: 1.20–1.34) and parental support (aOR = 1.07, 95%CI: 1.04–1.12) were more likely to meet the MSE recommendations.ConclusionLess than two-fifths of Chinese children and adolescents met the World Health Organization MSE recommendations. The correlates identified in our study can help inform the development of school and community based strategies and policies to enhance participation in MSE and improve muscular fitness of all Chinese children and adolescents. 相似文献
104.
基于模式匹配抽取技术的网上产品情报获取 总被引:1,自引:0,他引:1
产品生命周期的逐渐缩短迫使企业关注从因特网上大量、散乱的信息中及时获取新产品信息,跟踪竞争对手研发动向。本文引入基于模式匹配的自动Web信息抽取技术,叙述抽取产品的关键信息方法,并以家用冰箱性能参数信息的自动抽取为例,分析了冰箱领域知识,进行了样本页面的分析归纳,确认了冰箱产品的多种属性及产品信息抽取的模式特征,最终获得了清晰、结构化的产品数据,形成从Web页面上抽取同类产品关键信息的整个处理流程模型,成为网络环境下情报采集与分析的新情报研究模式的一个有力探索。 相似文献
105.
数字资源整合:信息资源管理领域的新课题 总被引:1,自引:0,他引:1
我们正面临这样一种信息环境的变革时期:数字信息日渐成为信息资源的主流载体,整序数字信息的异构资源系统急剧增加,数字资源局部有序但整体呈现无序的状况日趋严重,优化数字资源利用环境,有效获取信息知识成为人们关注的重点.如何利用新型的技术和方法,对局部有序而整体无序的数字资源进行类聚、融合和科学的重组,最终形成以知识组织体系为支撑的数字资源知识整合的大环境,提高数字资源传播与利用效率,既是图书情报界、企业界等领域数字资源建设的重要任务,也是信息资源管理领域的一个新的重要研究课题. 相似文献
106.
马晓燕 《高等工程教育研究》2008,(3):112-116
随着高校学生管理的民主化以及市场力量对高等教育的介入,"合同"开始被运用到我国高校学生管理之中。本文通过对学生管理合同文本的法律实证主义分析,认为目前学生管理合同具有行政合同的特征。相对于单方的校规管理方式,合同式管理是一种进步,但目前学生管理合同还存在着学生意思自治缺失以及合同合法性和合理性遭受质疑等问题。 相似文献
107.
文章运用文献资料法、逻辑分析法等研究方法,对把毽球这项优秀的传统体育项目引进高校的可行性因素进行了深度的分析,研究结果指出,在高校推广的途径如下:开选设修课程,在全校体育课中推广;加强师资培养,为毽球教学提供保证;加大力度宣传,为体育课程注入活力;努力搭建平台,实现与社区体育搭钩. 相似文献
108.
将职业教育作为本国教育发展的战略重点,已成为当前国际社会的共识,并表现出一些共通的特征,有必要进行一番梳理,以便对世界职业教育的发展轮廓有一个清晰的认识.当前国际职业教育的特征主要表现为:以需求为导向,注重学生综合职业能力的培养,深入开展校企合作教育,趋于均权化和协同化的管理,重视职业教育研究等. 相似文献
109.
我国台湾地区的职业教育被称为"技术与职业教育",简称技职教育.职业教育被公认为创造台湾经济奇迹的主要因素之一.台湾地区职业教育改革的实践可以为我们提供不少宝贵的经验和启迪,其缺点或失误,也可以给我们以警醒. 相似文献
110.