共查询到20条相似文献,搜索用时 15 毫秒
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Summary. Quercus × warburgii A. Camus, the Cambridge Oak, is a semi‐evergreen tree of hybrid origin, possibly between Q. rugosa Née and Q. robur L., and is only known in cultivation. Mature trees in gardens are extremely rare. Its history and cultivation are discussed. 相似文献
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Summary. The hybrid hazel, Corylus × vilmorinii Rehder is described and illustrated. Its robust habit and showy catkins make it an interesting and worthwhile tree to cultivate. 相似文献
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2021年1月11日,由联合国、世界银行和法国共同发起的第四届“一个星球”峰会通过线上线下相结合的方式在巴黎举行,本次峰会主题为生物多样性保护。峰会针对4个议题展开,分别是:(1)保护陆地和海洋生态系统;(2)促进生态农业;(3)生物多样性与资金筹措;(4)保护人类健康、物种和热带森林。对变化背景下的生物多样性保护主要有以下几个方面的启示:(1)识别优先保护区域,提高保护区有效性;(2)开展变化背景下的生态修复规划,提高自然-社会生态系统抗风险能力;(3)加强模型预测与情景分析,发展生物多样性与生态系统服务集成模型;(4)发展基于自然的解决方案,可持续利用自然资源;(5)加强后疫情时代国际间交流合作,开展生物多样性保护资金筹措工作。 相似文献
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2021年5月24日—28日第十一届国际根系研究大会和第九届根系发育研讨会(Rooting2021)联席会议由美国密苏里州州立大学和英国汉诺丁大学共同组织并在线举办。本次大会主题为“探索根系:发现新前沿”,参加会议的有来自世界51个国家,主要包括:美国、英国,澳大利亚、中国以及来自南美、欧洲和非洲的部分国家,共计693人参会。本届根系大会研讨领域广泛,涉及根的宏观到微观不同尺度的研究。预计未来根系领域研究热点主要集中在:根系表型研究技术的研究、根系的生态系统服务功能、根系的逆境生理学研究、根系与土壤交互作用、根系与微生物互作的研究以及根和根系发育等。 相似文献
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The “Grappin” or “Saint-Vincent's” cave, on the western slope of Jura, East of France, has been explored since 1889. From then to 1960, it has yielded substantial material dated to middle “à navettes” Magdalenian developing during the late Pleniglacial. The study of this settlement, although often mentioned, was never dealt with comprehensively until now. Due to its scientific importance for the middle Magdalenian of western Europe, the site is to be reinvestigated through a global interdisciplinary project entitled “The Tardiglacial and the start of Holocene in the Jura and its margins”. This paper will review our present knowledge of the site, radiocarbon dates and archaeological data. It also focuses on ornaments and engraved mobile art. 相似文献
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Summary. Rosa 'Cantabrigiensis' is a hybrid whose history is connected with Cambridge University Botanic Garden where it was raised and first recognised in 1922. Its origin in the experimental work on Rosa by Charles Hurst is discussed, and its likely parentage is given. 相似文献
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《Médecine Nucléaire》2023,47(3):120-130
Bone scintigraphy is a nuclear imaging scan using a radiopharmaceutical composed of a bisphosphonate coupled to a radionuclide (technetium 99 m). Radiopharmaceutical uptake is particularly important at the level of the bone structures having a strong osteoblastic activity. These uptakes can be due to a benign pathology (fracture, loosening of prosthesis, rheumatic pathologies, etc.) or to a malignant pathology (primary or secondary bone lesion). The high sensitivity of bone scintigraphy makes it particularly interesting at the initial stage of the pathology, especially when x-rays are normal. In addition, its specificity has clearly improved in recent years with the increasingly use of tomoscintigraphy coupled with X-ray scanning (SPECT/CT). We describe the operating principle of bone scintigraphy, normal uptakes with its variants as well as pathological uptake features in traumatic, rheumatic, prosthetic or cancerous pathologies. 相似文献
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Hikaru Takahara Shinya Sugita Sandy P. Harrison Norio Miyoshi Yoshimune Morita Takashi Uchiyama 《Journal of Biogeography》2000,27(3):665-683
A biomization method, which objectively assigns individual pollen assemblages to biomes ( Prentice et al., 1996 ), was tested using modern pollen data from Japan and applied to fossil pollen data to reconstruct palaeovegetation patterns 6000 and 18,000 14C yr bp Biomization started with the assignment of 135 pollen taxa to plant functional types (PFTs), and nine possible biomes were defined by specific combinations of PFTs. Biomes were correctly assigned to 54% of the 94 modern sites. Incorrect assignments occur near the altitudinal limits of individual biomes, where pollen transport from lower altitudes blurs the local pollen signals or continuous changes in species composition characterizes the range limits of biomes. As a result, the reconstructed changes in the altitudinal limits of biomes at 6000 and 18,000 14C yr bp are likely to be conservative estimates of the actual changes. The biome distribution at 6000 14C yr bp was rather similar to today, suggesting that changes in the bioclimate of Japan have been small since the mid‐Holocene. At 18,000 14C yr bp the Japanese lowlands were covered by taiga and cool mixed forests. The southward expansion of these forests and the absence of broadleaved evergreen/warm mixed forests reflect a pronounced year‐round cooling. 相似文献