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ALISON COOL 《American anthropologist》2009,111(1):99-101
ABSTRACT In June of 2008, the American-Scandinavian Foundation and the National Museum of the American Indian presented a screening of selections originally shown at the 12th annual Sámi Film Festival held in Norway. This marked the first time that a version of the festival, which features works by and about the indigenous peoples of Norway, Sweden, Finland, and Russia, was presented in New York. Three of the films shown— Last Yoik in Saami Forests?, Herdswoman, and Calmmis Calbmái ( From an Eye to an Eye) —examined how Sámi communities draw on shared traditions as a productive resource for reimagining Sámi identity in a contemporary context. [Keywords: Sámi, Scandinavia, indigenous media, ethnographic film] 相似文献
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Abstract: A recent collection of actinopterygian fossil fishes from a previously unreported locality in the Cenomanian or Turonian of southeastern Morocco includes a single specimen of a macrosemiid fish. Macrosemiids are more common in Jurassic and Early Cretaceous deposits, with the previously known range of the family being Late Triassic through Aptian or Albian. This discovery therefore extends the temporal range of the family into the Late Cretaceous. Moreover, macrosemiids had not previously been reported from northern Africa or the Moroccan area of the Tethys basin; therefore, this fossil also increases the geographical range of the family. The Moroccan macrosemiid is described in a new genus and species, Agoultichthys chattertoni . A phylogenetic analysis places it basal to all other genera of the family with the exception of Notagogus . Diagnostic characters of the new species include the high number of scales laterally along the body and the greater number of dorsal fin rays than in other members of the family. 相似文献
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BENJAMIN BURGESS HAYLEY MOUNTFORD CLARE J. HOPKINS CHRISTOPHER LOVE ALISON E. LING GERMAN C. SPANGENBERG DAVID EDWARDS JACQUELINE BATLEY 《Molecular ecology resources》2006,6(4):1191-1194
The availability of sequence data derived from shotgun sequencing programs enables mining for simple sequence repeats (SSRs), providing useful genetic markers for crop improvement. This study presents the development and characterization of 40 SSR markers from Brassica oleracea shotgun sequence and their cross‐amplification across Brassica species. The markers show reliable amplification, genome specificity and considerable polymorphism, demonstrating the utility of SSRs for genetic analysis of commercial Brassica germplasm. 相似文献
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ALISON S. SCOTT BROWN MONIQUE S. J. SIMMONDS 《Botanical journal of the Linnean Society. Linnean Society of London》2006,152(1):109-130
This study highlights the morphological differences between two groups of plants; those that are recorded as hosts of the thrips Heliothrips haemorrhoidalis (Bouché) and those that remain free from infestation. Scanning electron microscope techniques were used to describe the morphology of the leaf surface of 19 species in order to help identify which morphological features could play a role in the selection of plant species by thrips from among a diverse botanical collection. H. haemorrhoidalis had a preference for species with leaves that were coriaceous, with one or both surfaces being smooth. Plants evading these thrips commonly possessed glandular trichomes. Thus morphology may have a role in deterring thrips from the leaf surface, as well as influencing the behaviour of predators that control thrips. Further detailed studies into the chemistry of leaves of hosts and nonhost species may help to further our understanding of selection mechanisms. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 109–130. 相似文献
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Understanding the departure decisions of migratory birds is critical for determining how changing climatic conditions will influence subsequent arrival times on the breeding grounds. A long‐term dataset (1972–2008) of Whooper Swan Cygnus cygnus departure dates from a wintering site in Ireland was used to assess the factors determining the timing of migration. Early and late migrating swans showed different departure patterns. Earlier wintering ground departure was more pronounced for the first 50% of the population than the last 10% of departing individuals. Earlier departure was associated with an increase in February temperatures at the wintering site for all departure phases except the date when the last individual departed. The date by which the first 50% of Swans had departed was earlier with increasing numbers of wintering Swans, suggesting that competition on the wintering grounds may further influence the timing of departure. The results also suggested that departure is mediated by the influence of spring temperature on food resources, with increased February grass growth in warmer years enabling earlier departure of migrating Swans. To determine why arrival dates in the breeding ground have altered, environmental conditions in the wintering grounds must be taken into account. 相似文献
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PHYTOALEXINS, WATER-STRESS AND STOMATA 总被引:1,自引:1,他引:0
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Simulated swards of Lolium perenne cv. S.23 growing in the fieldwere shaded at various stages of regrowth during August andSeptember, when insolation was most likely to be limiting. Reductionof ambient illumination to 50 per cent for periods up to 24days had little effect on the current production of herbage(mainly leaf blade), which progressed at the expense of rootand stubble growth. After defoliation, however, previously shadedswards transferred to full light regrew relatively slowly. Leafarea and leaf extension were increased by shading, but leafappearance rates were only slightly affected. Shading decreasedtiller densi ties, and hence stubble yields, but did not affectmean tiller weights. The dangers of relating herbage yield tocurrent rates of insolation and photosynthesis, and the relevanceof these findings to other grass varieties are discussed. 相似文献