51 resultados para Pontes, Belchior de, 1644-1719.

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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National Natural Science Foundation of China [40201005]; Knowledge Innovation Project of Chinese Academy of Sciences [KZCX3-SW-321, KZCX2-314, KZCX1-SW-321-4]

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建立了一种考虑多种非线性因素的张力腿平台(TLP)模型,其中包括六自由度有限位移、各自由度之间的耦合、瞬时湿表面、瞬时位置、自由表面效应、粘性力等因素引起的非线性。推导出TLP六自由度非线性运动方程。对典型平台ISSCTLP进行了时域上的数值计算,求得该平台在规则波作用下的六自由度运动响应。用退化到线性范围的解与已有解进行了对比,吻合良好。数值结果表明,综合考虑非线性因素后响应有明显改变。

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<正> 一、空间科学 空间科学研究行星系统、恒星系统、星系、宇宙、以及生命物质等宇宙空间客体的结构和演化;以及在地球外空间进行生理学、生物学及微重力科学等精心设计的实验和研究。前者是在外层空间进行观测和测量,后者是将地面实验室的研究延伸到外层空间。当本世纪五十年代人造地球卫星被成功地发射到地外空间以后,人类的科学视野就极大地拓展了,人们可以直接地测量地球空间和行星

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We investigate the fluorescence spectrum in a nearly degenerate atomic system of a F-e = 0 -> F-g = 1 transition by analytically solving Schrodinger equations. An ultranarrow fluorescence spectral line in between the two coherent population trapping windows has been found. Our analytic solutions clearly show the origin of the ultranarrow spectral line. Due to quantum interference effects between two coherent population trapping states, the width and intensity of the central spectral line can be controlled by an external magnetic field. Such an effect may be used to detect a magnetic field.

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Theoretical and experimental results are presented for simultaneous multibeam coupling in photorefractive SBN:Ce. Within a single crystal, multiple signals are amplified through a coupling process that employs a single pump. The coupling gain of each signal results from coupling both between the pump and the signal and between different signals. The amount of gain that each signal receives is dependent on the intensity of the incident signal; thus a competition for the gain exists among the various signals.

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传统的低等金缕梅类包含7个科,即领春木科(Eupteleaceae)、昆栏树科(Trochodendraceae)、水青树科(Tetracentraceae)、连香树科(Cercidiphyllaceae)、折扇叶科(Myrothamnaceae)、悬铃木科(Platanaceae)和金缕梅科(Hamamelidaceae)。这些科之间的谱系关系以及金缕梅科内部的谱系关系是研究被子植物系统和进化的主要问题之一。本研究的目的在于通过对现有的和本研究中产生的分子和发育学资料的分析来对这些谱系问题进行探讨,希望使我们对这些类群的认识提高到了一个新的水平。 本研究测定了包括连香树科、领春木科、悬铃木科、水青树科和金缕梅科内所有亚科代表共计14个种的rbcL基因,matK基因和18S-26S核核糖体(nrDNA)内转录间隔区(ITS)的序列,并结合原有资料对所有低等金缕梅类(除非洲分布的折扇叶科)及其相近类群进行了分支分析。主要结论包括;传统低等金缕梅类是一个复系类群;金缕梅科也是一个复系类群;ITS序列分析支持将连香树科包含在金缕梅科内,但是,rbcL资料和matK资料不支持将连香树科包含在金缕梅科内。本研究支持金缕梅科内6个亚科的分类系统,即将其分为阿丁枫亚科(Altingioideae)、红花荷亚科(Rhodoleioideae)、马蹄荷亚科(Exbucklandioideae)、壳菜果亚科(Mytilarioideae)、双花木亚科(Disanthoideae)和金缕梅亚科(Hamamelidoideae),但壳菜果亚科的山桐柴属(Chunia)应置于马蹄荷亚科内。 本研究首次描述和报道了金缕梅科5个亚科6个种的花的形态发生。通过对本研究发现的新证据和文献中记载的资料分析表明金缕梅科的花发育的特征无明显的共同式样。从本研究提供的花发育资料得出的值得注意的结论是红花荷属在金缕梅科中的亚科地位得到支持。对牛鼻栓(Fortunearia sinensis Rehd. et Wils.)的花发育研究表明其花性分化在发育晚期才出现。 本文首次对显脉红荷(Rhodoleia henryi Tong)的胚胎学进行了研究。尽管红花荷属是金缕梅科内适应鸟传粉的特化类群,但其胚胎学的特征与金缕梅科其它植物并无明显区别。因此,本研究不支持红花荷属独立成科而支持其在金缕梅科内的亚科地位。

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本发明属于生物医学领域。大蹼铃蟾蛋白酶抑制剂,从两栖类动物大蹼铃蟾皮肤中分离得到的一种单链丝氨酸蛋白酶抑制剂,其在SDS-聚丙烯酰胺凝胶电泳上的表观分子量还原条件下为67KDa,非还原条件下为45KDa,等电点4.8,糖含量17—19%,无酶活性,大蹼铃蟾蛋白酶抑制剂的N—端31个氨基酸序列结构是:DSETHIRFLGEVYKKVDTIDFRGLVLITRAQ。其制备方法是取大蹼铃蟾皮肤,在生理盐水中匀浆后,离心去除沉淀,收集上清液冷冻干燥后,经离子交换,凝胶过滤纯化后得到。具有强烈的丝氨酸蛋白酶抑制活性和抗肿瘤活性,作为制备肿瘤治疗药物和制备治疗胃炎、胰腺炎及其他炎症药物的应用。

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Changes of plasminogen activators (PA) during different stages of development of the corpus luteum, and their possible physiological role in luteolysis were studied in rhesus monkeys. It was demonstrated for the first time that monkey corpus luteal cells not only produce PA, but that the function of the corpus luteum is also closely related to the activity of this enzyme system. Generally, the life span for a corpus luteum in monkey is approximately 14-16 days, its demise beginning thereafter. In the present study, we found that urokinase in the corpus luteum is higher on day 5 and day 10 after human chorionic gonadotrophin injection, while the tissue type (t) PA is mainly produced on day 13 when luteolysis may take place. Progesterone production remained high on day 5 and day 10 and decreased dramatically from day 13, indicating the important role of tPA but not urokinase (u) PA in suppressing luteal function. When purified tPA (but not uPA) monoclonal antibody was added to luteal cell culture to neutralize endogenously produced tPA activity, progesterone production in the cells was increased significantly. Interestingly, prolactin alone was capable of increasing PA production by luteal cells; prolactin together with luteinizing hormone, however, had a synergistic luteotrophic effect.

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2009年12月14—15日,武汉观鸟爱好者廖晓东(网名:僵鱼)分别在云南省勐腊县中国科学院西双版纳热带植物园和景洪市云南省热带作物科学研究所内拍摄到取食花蜜的小型鸟类。经鉴定,所摄两张照片中的鸟,均属褐喉直嘴太阳鸟