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121.
19世纪在美国发生了一系列暴力排华事件。具有代表性的暴力排华大案有洛杉矶惨案,旧金山骚乱,丹佛惨案,石泉大屠杀,西雅图事件和塔科马事件等。暴力排华由加州发展到西部诸州,由分散,零星,无组织的暴力排华事件发展为集中,广泛,有组织的暴力排华运动,0功工是暴力排华的主力,劳动骑士团在暴力排华运动中发挥了极为重要的组织作用和领导作用。  相似文献   
122.
安全困境与后冷战时代的中美关系   总被引:2,自引:0,他引:2  
安全困境是国际关系中的一个基本特征。通过分析安全困境发生的原因,提出安全困境的两种模式:一般性安全困境和结构性对抗安全困境,在此基础上对冷战后中美关系中存在的安全困境的性质和特征进行了分析,并指出对台湾问题的思考应该放在冷战后中美安全困境的背景之中。  相似文献   
123.
通过利用文献计量的方法,对华南师范大学近10年(1994-2004年)的自然科学研究项目和成果在国内获奖情况进行统计分析,为学校科研管理部门的规划提供了一些参考。  相似文献   
124.
SCI 与SSCI 收录华南师范大学学术论文的统计与分析   总被引:4,自引:0,他引:4  
以美国科学情报社的Web of Science网络数据库为依据,对1994~2003年问SCI和SSCI收录华南师范大学学术论文情况,从论文数量、学科、作者和期刊的角度进行了归类、统计与分析.最后指出:华南师范大学要提高国际影响力,必须在SCI和SSCI论文的数量和质量上有所突破.  相似文献   
125.
A small collection of fishes from the Bonaparte Seamount (15°40′S, 6°55′W, 130 km west of Saint Helena Island, least depth 105 m), comprising 14 specimens from nine species in eight families, is described. This appears to be the first collection of fishes reported from the seamount. In addition, seven new records for St Helena (15°58′S, 5°43′W) are reported as well as additional specimens of several rarely caught endemics. The scorpaenid Pontinus nigropunctatus, previously known only from St Helena, is now also reported from Bonaparte Seamount while the serranid Holanthias fronticinctus, also considered a St Helena endemic, has been found to comprise 20% of the diet of yellowfin tuna (Thunnus albacares) at the Seamount. The carangid Decapterus muroadsi which was previously recorded in the Atlantic only at St Helena is now also recorded from the Bonaparte Seamount. A second specimen of the primarily Indo-Pacific carangid Uraspis helvola is recorded from St Helena (third record for the Atlantic). Particularly interesting new records at St Helena, which represents significant range extensions, are of Corniger spinosus (Holocentridae), and of Carangoides ruber and Seriola fasciata (Carangidae). The potential role of shallow seamounts around Ascension and St Helena as ‘stepping stones’ between the two islands is discussed.  相似文献   
126.
《Journal of Natural History》2012,46(5):1303-1309
Erikus dahli, a new genus and species in the amaryllidid group of lysianassoid amphipods, is described and illustrated from South American material.  相似文献   
127.
《Journal of Natural History》2012,46(11):1597-1615
Over 8000 amphipods were examined from coastal (primarily intertidal) and anchialine pool habitats of Ascension Is. Twenty-seven species, of which 14 are undescribed, were identified. Comparison of species from Ascension with amphipods found in possible source areas suggests that most colonization of the island by these animals has been via the Benguela Current. Possible western Atlantic faunal contributions are significantly lower than for other marine taxa that have been studied at Ascension, all of which are generally characterized by having dispersive larval stages. The high proportion of apparently endemic species, which exceeds that described for amphipods of other oceanic islands, is probably due to both the island's isolation and incomplete faunal surveys in possible source areas. Amphipod species diversity is low, a probable consequence of the size, isolation, youth and low habitat variability of Ascension Is. Consistent with other Atlantic islands that have been studied, nestlers predominate (56% of the species), with tubicolous species (33%) of secondary importance and inquilines (11%) making only a minor contribution. Three species occur in the anchialine pool habitat. Rather unexpectedly, caprellid amphipods are absent.  相似文献   
128.
《Journal of Natural History》2012,46(23):2125-2136
A morphological investigation of Leydigia parva Daday, (Chydoridae: Anomopoda: Cladocera), based on specimens from Paraguay (type specimens) and Brazil, clarifies its position in the subfamily and prompts its assignment to a new genus, Parvalona. The affinity of this rare benthic chydorid with Leydigia Kurz, 1875 and Alona Baird, 1843, in which this taxon was placed earlier, is discussed.  相似文献   
129.
《Journal of Natural History》2012,46(38):3369-3405
New records are given of the water mite family Hygrobatidae (without the genus Atractides) from southern Africa (South Africa, Botswana, Namibia). In addition to one new subgenus of the genus Hygrobates, namely Inflatibates, four new species are described, namely Hygrobates draconicus, H. laceratoides, H. okavangoensis, and H. inflatipes as well as one new subspecies, namely Hygrobates spathuliferus cederberg. The following synonyms are established: the subgenus Capobates Thor with Hygrobates Koch, Hygrobates sanguineus transvaalensis K. O. Viets with Hygrobates spathuliferus (Lundblad), and Ambiguobates permixtus agnewi K. O. Viets with Ambiguobates permixtus K. Viets. The male of Australiobates pilosus (K. Viets) is described for the first time. The synonymization of Diversibates with Australiobates can now be confirmed. Finally, keys are given for the known genera of southern Africa, as well as for all known species of the genus Hygrobates from southern Africa.  相似文献   
130.
《Journal of Natural History》2012,46(25-26):1793-1804
The eumaeine hairstreak species Thecloxurina tegulina Bálint and Boyer, sp. n. from SW Peru, department Apurímac (type locality: Karkatera, NW of Ampay, 3,200 m, 13°34′286″S; 72°58′501″W) is described on the basis of qualitative and quantitative wing pattern, male genital and spectral characters. The spectral reflectance of the closely related genera Penaincisalia and Thecloxurina are investigated and compared. It is demonstrated that the spectral characteristics of the two genera are qualitatively differing, and the taxa investigated representing the two genera (Penaincisalia:Thecloxurina = 3:5) also have characteristic species dependent reflectance peaks measured at normal incidence.  相似文献   
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