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MORGAN PERKINS 《American anthropologist》2004,106(3):595-599
This review essay of Across Borders: Beadwork in Iroquois Life focuses on the display of beadwork as a cultural practice that has evolved significantly throughout its history while remaining central to Iroquois identity. The exhibition draws on historical documentation, objects, and imagery that depict the varied uses of beadwork as ritual objects, sources of income, markers of identity, and as works of art. The content and narrative for the display was developed through a broad collaboration between curators, scholars, artists, and members of two Iroquois communities. The changing and continued importance of beadwork is reflected in the adaptation of materials and styles for different forms of production and use. Across Borders places Iroquois beadwork in a broad context while concentrating on specific forms and meanings that are attached to beadwork, whether created in community gatherings or by individual artists. 相似文献
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DAVEY M. R.; MULLIGAN B. J.; GARTLAND K. M. A.; PEEL E.; SARGENT A. W.; MORGAN A. J. 《Journal of experimental botany》1987,38(9):1507-1516
Davey, M. R., Mulligan, B. J., Gartland, K. M. A., Peel, E.,Sargent, A. W. and Morgan, A. J. 1987. Transformation of Solanumand Nicotiana species using an Ri plasmid vector.J. exp.Bot. 38: 15071516. Five Nicotiana species (N. benthemiana, N. debneyi, N. occidentals,N. plumbaginifolia, N. tabacum) and three Solanum species (S.dulcamara, S. nigrum, S. tuberosum) were transformed by wild-typeand engineered Ri plasmids. Depending on the host plant, rootstransformed by Agrobacterium strain A4TIII with an Ri plasmidcarrying a chimaeric nopaline synthase-kanamycin resistancegene, were 3 to 40 times more resistant to kanamycin than rootstransformed by the wild-type plasmid of strain A4T. Similarly,plants regenerated from A4TIII-derived roots of N. debneyi,N. plumbaginifolia and N. tabacum were 8 to 16 times more resistantthan A4T plants, and survived at 400 µg cm3 of kanamycin.A4TIII plants of S. nigrum flowered in vitro at 6001000µg cm3 of kanamycin. Transformed roots and most regeneratedplants synthesized Ri-speciflc opines, while DNA hybridizationconfirmed the presence of DNA homologous to that from wild-typeand engineered Ri plasmids in transformed plants of S. nigrum. Key words: Agrobacterium, Ri plasmid, transformed roots, plant regeneration, kanamycin resistance. 相似文献
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The Use of Coleoptile Responses to Water Stress to Differentiate Wheat Genotypes for Osmoregulation, Growth and Yield 总被引:3,自引:0,他引:3
Differences in osmoregulation between genotypes of wheat (Triticumaestivum L.) were identified by measuring responses of coleoptilesto water stress. Seeds were germinated in Petri dishes on germinationpads. Water stress was applied when coleoptiles were 1 cm longby either adding polyethylene glycol 6000 (20% w/w) or by removingthe lids of the dishes and allowing the pads to dry by evaporationfor a period of 2 d, or from the beginning of germination byvarying the amount of water in the germination pads. Measurementsof the water and osmotic potentials of shoots and roots (usingthermocouple psychrometers) were used to estimate turgor pressures.Wheat genotypes showed the same segregation for shoot and rootlengths and turgor pressures as they had done in previous studiesfor flag-leaf osmoregulation and yield. It was concluded thatobservations of the responses of coleoptile length to waterstress could be used in plant-breeding applications to identifydifferences in osmoregulation between genotypes of wheat. Triticum aestivum, osmoregulation, turgor maintenance, coleoptile growth, root, selection criterion 相似文献
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Respiratory Loss of Recently Assimilated Carbon in Wheat 总被引:2,自引:0,他引:2
A series of experiments was undertaken to assess the amountof respiration associated with the growth of wheat at differentstages. Plants (or in some cases just the flag leaf) were labelledwith 14CO2 and the amount of 14CO2 respired during the subsequent48 or 72 h was measured. The evolution of 14C, expressed asa percentage of the amount initially assimilated (referred toas the R/A value) was used as a measure of the overall efficiencyof dry matter production. Respiratory 14CO2 evolution from labelledplants was most rapid in the first 12 h after labelling, thereafterdeclining rapidly. Evolution was also more rapid following labellingsat the end of the light period (dusk) than at the beginningof it (dawn). The R/A values were greatest (42 and 50 per centrespectively for dawn- and dusk-labelled plants) for young plantsand least (13 and 28 per cent respectively) for plants duringmid grain filling. When flag leaves, as distinct from wholeplants, were labelled, R/A values were lower still (9 and 21per cent respectively), indicating that flag leaf assimilatewas used efficiently in grain production. The calculated minimum R/A for the formation of grain material(10 per cent protein, 90 per cent starch) was 6.2 per cent.That the experimentally determined values were greater thanthis is attributed to the turnover of carbon in enzymes, toother maintenance processes, and possibly to the operation ofthe pentose phosphate pathway of glucose oxidation. R/A valueswere lower in those plants labelled at the beginning than thoseat the end of the photoperiod. This was considered to be a consequenceof refixation of respiratory 14CO2 during the light. The higherR/A values found for young plants were considered to be a consequenceof the greater percentage of 14C translocated to the roots (rootsbeing unable to refix respired CO2) and of greater turnoverof enzymes associated with more active metabolism. Triticum, wheat, respiration, carbon assimilation, carbon loss, grain-filling 相似文献
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CELLS from patients with G-trisomy or E-trisomy and XXY cells from patients with XY/XXY mosaic Klinefelter's syndrome are more susceptible to transformation in vitro by SV40 than are cells from normal individuals1–3. We have used triploid (69XXY) human cells to determine whether the presence of extra chromosomes per se increases susceptibility to transformation. 相似文献
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Primary Structure of Lysozymes from Man and Goose 总被引:4,自引:0,他引:4
The primary structure of goose egg white lysozyme seems to be distinct from that of hen egg white and human leukaemia lysozymes. 相似文献