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1.
There is no consensus regarding the origin of the term decussatio pyramidum. Various anatomists of the past are honored by modern scholars, for example, Vieussens, Reil, and Collins. However, contralateral effects of brain lesions were already mentioned in Hippocratic treatises. Aretaeus of Cappadocia assumed that the anatomical reason for this phenomenon is the interchange of the nerves and called it chiasmos. This opinion was discussed in modern times and the anatomists used the term decussatio nervorum. The authorship of the first demonstration of decussatio pyramidum is given to Mistichelli (1709) and Petit (1710), but neither the term decussatio nor any of its vernacular forms are present in their work. A milestone in the history of the term is the Mémoire of Gall and Spurzheim presented to the Institut de France in 1808. In the French printed form of the Mémoire (1809), the word combination décussation des pyramides was used for the first time in anatomical literature.  相似文献   

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Assuming lightning discharge as a plasma it is shown that Bremsstrahlung is a possible source of UHF emissions. The computed power gives a flat frequency response with a magnitude of about 10−15 W m−2 Hz−1 at a distance of 1 km from the base of the channel. While partially ionized channels like stepped leader, dart leader and K-changes are the strong source of UHF emissions, the radiation from the return stroke is negligible. Our theoretical results are in excellent agreement with the experimental observations of Book and Kitagawa (1964) and Kosarevet al. (1969, 1970).  相似文献   

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The possibility of the generation of decameter scale ionospheric plasma density irregularities, that must be responsible for dusk scatter, by the plasma gradient drift instability (GDI) at F-region altitudes is considered. It is shown that the dusk scatter could be produced by the ion density perturbations which appear as a result of the development of the GDI produced by the maximum westward plasma drift in the region poleward of the trough minimum. Possible reasons for the appearance of growth of the GDI waves as a result of the development of the trough plasma GDI during or just after sunset in the F-region are discussed. It is shown that, if the GDI begins after sunset, then the influence of the drift velocity shear results in the action of the GDI during 1–2 hours after sunset, which is close to the duration of dusk scatter.  相似文献   

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The Italian psychiatrist Ernesto Lugaro can be regarded as responsible for introducing the term plasticity into the neurosciences as early as 1906. By this term he meant that throughout life the anatomo-functional relations between neurons can change in an adaptive fashion to enable psychic maturation, learning, and even functional recovery after brain damage. Lugaro's concept of plasticity was strongly inspired by a neural hypothesis of learning and memory put forward in 1893 by his teacher Eugenio Tanzi. Tanzi postulated that practice and experience promote neuronal growth and shorten the minute spatial gaps between functionally associated neurons, thus facilitating their interactions. In addition to discovering the cerebellar cells known by his name and advancing profound speculations about the functions of the glia, Lugaro lucidly foresaw the chemical nature of synaptic transmission in the central nervous system, and was the first to propose the usage of the terms "nervous conduction" and "nervous transmission" in their currently accepted meaning.  相似文献   

7.
论宋代纸币发行的缘起   总被引:1,自引:0,他引:1  
岳毅平 《安徽史学》2004,(4):99-101
宋代是人类历史上首次大规模发行纸币的时代,对后世产生了深远的影响,本文从商品交换、铸币能力、财政需求等几个方面探讨宋朝纸币产生和广泛使用的原因.  相似文献   

8.
This paper examines evidence for the origin of the tree Spondias mombin in Africa, where it is generally described as introduced from the Neotropics. Based on biogeographical, ecological, and historical evidence, this paper argues that the tree reached Africa via natural, long-distance dispersal, and should be considered an African native plant. The idea that it is introduced appeared in 1868, when it was a scientifically justifiable conclusion reflecting the limitations of nineteenth-century biogeographical knowledge. By the early twentieth century, representing Spondias mombin as a human introduction in Africa was no longer scientifically justifiable because of advances in knowledge of the African flora and plant dispersal ecology. Nonetheless, most authors continued to represent the tree as introduced, in part because such representation was consonant with dominant images of the African environment: (a) that the continent had suffered extensive deforestation in the recent past, and (b) that Africa's flora was depauperate in fruit trees prior to the coming of Europeans. Recent authors continue to describe Spondias mombin as introduced because they have not sufficiently considered the historic contexts of primary and secondary sources on Neotropical plant introductions in Africa. This paper concludes that the human role in creating the African portion of the trans-Atlantic tropical flora has been overemphasized. Natural plant dispersal across the Atlantic may be more frequent than generally accepted.  相似文献   

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Although there are problems in dating the Arthasastra precisely, the period it refers to (c.300 B.C.—300 A.D.) is of considerable importance in the settlement history of Southern Asia. The work is usually regarded as a source for political and constitutional history but contains a great deal of significance to the historical geographer, and this paper highlights its contributions on urban planning, rural‐urban relationships, and the spatial organisation of early Indian city‐states. The question is raised of whether it remained simply a plan‐image or can be regarded as a guide to reality.  相似文献   

10.
主要从地下考古资料阐述了新石器时代东夷文化的有序性和承继性、先进性、影响性和辐射性等三大优势和特点,从而论证了东夷文化才是华夏文明孕育的真正母体、中华文明的主源头.  相似文献   

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Summary Beginning with the synchronic metrical distribution of and ‘NEG’, we attempted to formulate, first, certain principles of Rig-Vedic exegesis (which we applied to several obscure or hitherto imperfectly understood passages), and second, a theory concerning the origin of the comparative function of . Unlike previous explanations, the theory described above accounts in a systematic way for the formal, functional, and metrical features of . We considered, in addition, the following theoretical points: possible implications of phraseology for the historical analysis of Rig-Vedic meters; the lack of universal principles, as yet, for predicting the direction and nature of secondary marking in the case of functional split of a particle; the interaction of secondary phraseological patterns with original phraseology, resulting in synchronic irregularity in metrical distribution. Finally, we suggested that the syntactic behavior of and ‘NEG’ confirms the theory presented here concerning the origin of .  相似文献   

13.
徽州人在《近思录》及其整理本的传播历程中发挥着重要作用。汪佑汇辑朱熹之言,增入《近思录》各卷末,合编为《五子近思录》十四卷。此书"大成全观","朱子集大成之梗概,昭著于世,而四先生之言,益有所论定折衷"。汪佑此编在清初朱子学传承发展上作出了重要贡献,使程朱之学思想内容更趋完善。汪佑《五子近思录》面世后,重刻者接踵而至。其传刻本之多是任何一本《近思录》续编本难以企及的,推动了程朱理学学术思想的盛传。  相似文献   

14.
Touchstones are pieces of fine-grained black stone which are used for assaying gold by comparing the colour of streaks made on the surface by alloys of known composition with the colour of the streak from an object of unknown composition. The technique has been in use since at least the 6th century BC.The petrographic aspects of the identification of touchstones are reviewed and 42 historical touchstones or museum specimens of similar looking stone are described, most of them including the results of petrographic examination.The results show that touchstones usually consist of sedimentary rock types, of which the most frequently occurring ones are tuffs, cherts and siltstones.  相似文献   

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Anatomical features related to water deficiency were analyzed in archaeological plant charcoal as a paleoenvironmental indicator. The end of the Aguada settlements in the Valley of Ambato (Catamarca, Argentina), which took place towards the end of the first millennium of this era, was used as the case study. Tools from Ecological Anatomy were applied to recreate paleoenvironmental scenery for the studied processes. The results of the analyses showed that this area must have been undergoing a period of arid conditions during the studied period.  相似文献   

17.
陶寺文化与唐尧、虞舜 论华夏文明的起源(下)   总被引:6,自引:0,他引:6  
五、陶寺龙山文化的特征 和社会性质 陶寺文化在中原龙山文化中,有一群由铜器、木漆器、彩绘器、玉(石)器等组成的别具自身特征而又与众不同的器物群[22]。足以说明它的社会组织形态是一个部落联盟古国的国家载体。其中最具代表性者,为下列遗存。 (一)文化特征 1.铜器 在陶寺墓葬中,发现了一件铜铃或铜铎,它虽出自晚期墓葬,但却是一件工艺复杂的迄今年代最早的复合范的大型铜器。由于它是合范铸造,表明陶寺铜器由来有时,是其在早期就已出现的佐证。所以我们说陶寺文化的社会已进入了文明古国,铜器就是一个时代的标志。 2…  相似文献   

18.
陶寺文化与唐尧、虞舜——论华夏文明的起源(上)   总被引:3,自引:0,他引:3  
中国历史悠久,文献典籍丰富,在考古学文化方面。近40年来无论是田野发掘。还是课题研究,均获得了一系列的成果。然而如何将考古材料与历史传说相结合,复原中国史前史或上古史的本来面目,重建中国古代文明,这是近几十年来几代人所关注和企盼的。但这项极有意义的考古学研究工程的进展。  相似文献   

19.
ABSTRACT

Reader-oriented intertextuality opens perspectives to see the in-terpretation of the Hebrew Bible in the New Testament and in rabbinic litera-ture in a new light. This article discusses possible readings of the crux inter-pretum Leviticus 12,2 in the New Testament (Hebrews 11,11) and in rabbinic literature. It shows that both play with manifold meanings and facets of texts from the Hebrew Bible in a sometimes associative way, linking different con-texts with one another and creating a new intertextual network.  相似文献   

20.
拔河作为一项游戏和运动,其历史之悠久,流行之广泛,是其他许多运动项目所不及的。然而, 关于拔河运动的发源地,至今未有定论。本文联系韩国文化与楚文化的关系,并考据中日韩三国大型拔河运动的形式、特点与功能,认为这项古老的运动源自我国荆楚大地的襄阳、江陵一带。楚国的“牵钩”,作为楚军配合水战的一种军事技能,不仅具备了后来韩日等国拔河运动的要素,也是世界上最早用文字记录下的拔河运动,后世的拔河即由此演变而来。  相似文献   

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