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Mitochondrial DNA analysis of Scottish populations of Arctic charr, Salvelinus alpinus (L.) 总被引:2,自引:0,他引:2
Mitochondrial DNA analysis of a total of 82 individuals from seven Scottish populations of Arctic charr ( Salvelinus alpinus L.) using restriction fragment length polymorphism and direct nucleotide sequencing of the cytochrome b gene revealed little variation within or between populations. One of 19 restriction enzymes showed a polymorphism that was present in three of the seven populations. Only one nucleotide substitution was detected in a 288 base pair segment of the cytochrome b gene examined in 26 fish. Approximately 4% of the mitochondrial genome was surveyed with these complementary procedures. 相似文献
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Chemical composition studies on some aquatic macrophytes in three Scottish lochs. I. Chlorophyll,ash, carbon,nitrogen and phosphorus. 总被引:2,自引:2,他引:0
Y. B. Ho 《Hydrobiologia》1979,63(2):161-166
The chlorophyll, ash, carbon, nitrogen and phosphorus levels in seven species of freshwater macrophytes (Juncus effusus L., Iris pseudacorus L., Carex rostrata Stokes, Glyceria maxima (Hartm.) Holmberg, Nuphar lutea (L) Sm., Polygonum amphibium L. and Schoenoplectus lacustris (L) Pallas) in three Scottish lochs of different trophic levels were studied during 1975. Mean chlorophyll levels varied from a minimum of 1.73 mg g–1 dry weight in Balgavies Loch Juncus to 10.22 mg g–1 dry weight for Forfar Loch Iris. Carbon contents ranged from 450 to 520 mg g–1 ash-free dry weight. For ash, nitrogen and phosphorus, significant differences in mean concentrations were detected among plant species as well as within one plant species growing in different lochs. Positive correlations were apparent between the degree of eutrophication in the study areas and the amount of ash, phosphorus and nitrogen present in the plants growing in them. 相似文献
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Y. B. Ho 《Hydrobiologia》1979,63(1):33-43
Growth, chlorophyll and mineral nutrients studies were made in Phalaris arundinaceae L. in three Scottish lochs of varying nutrient status from March to November in 1975. The maximum shoot height and shoot dry weight attained by the plants were approximately 160 cm and 4 g respectively. Seasonal changes in the chlorophyll levels in the Phalaris leaf were studied and two peaks were found, one in April and the other in June–July. Maximum chlorophyll level attained was 9 mg g–1 leaf dry weight. The changes in the mineral levels in the root, stem, leaf and inflorescence parts of the plants from the three lochs were also assayed throughout the growing season. A total of eight mineral elements were studied, including carbon, nitrogen, phosphorus, potassium, sodium, calcium, magnesium and iron. Variations in both the mineral concentrations and their pattern of changes during the study period among the plants from the lochs were observed and discussed. 相似文献
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The problematic relationship between 'Britishness' and the identities of UK ethnic minorities is further complicated in Scotland by the increasing salience of the Scottish dimension. This article discusses the relationship between reformulations of 'post-British' national identities, and the position of Scottish Pakistani-Muslims. The study focuses on the preferred identities of young Pakistani-Scots in West Central Scotland, reporting chiefly on the results of the modified Twenty Statement Test [TST] as administered to sixty-three Scottish-Pakistani teenagers aged between fourteen and seventeen years, estimated as a significant percentage of the Glasgow Pakistani population in this age range. Religious, ethnic and nationality labels are all adopted by these respondents. Where there are no constraints on their identity labels, religious (Muslim) statements predominate, and where a choice of labels is provided, dual ethnicity labels are preferred. The results are theorized in relation to present deficiencies in the acceptance of plural or 'hyphenate' identities within the United Kingdom. 相似文献
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Learned vocal signals of birds provide one of the most comprehensive sources of evidence for culture in animals. Such vocal signals often vary spatially and temporally. Signal variation can be driven by direct factors such as cultural drift and selection or by indirect factors such as changes in the environment, which may affect morphology and therefore acoustic capability. In this study we analysed flight and excitement calls of several call types of the Red Crossbill Loxia curvirostra and other crossbill species. Calls were recorded between 1962 and 2019 across the Palaearctic region. We measured acoustic similarity within flight and excitement calls and modelled the size of the effect attributed to temporal and geographical distance. Geographical distance between different sampling locations explained less call variation compared with temporal distance, and temporal variation within the excitement calls was smaller than in the flight calls. We conclude that calls of most call types of Red, Scottish and Parrot Crossbill are an example of cultural evolution. We suggest that excitement calls are less modifiable because they can serve better in dangerous situations when they are stable in time and space. In addition, we found no clear support for increasing or decreasing flight call similarity of call types while or after being in contact, as found in another study from North America. The reasons for the cultural evolution in calls of Palaearctic crossbills remain unclear. 相似文献
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Mineral composition of Phragmites australis in Scottish lochs as related to eutrophication. I. Seasonal changes in organs 总被引:1,自引:1,他引:0
Y. B. Ho 《Hydrobiologia》1981,85(3):227-237
Monthly levels of nitrogen, phosphorus, potassium, sodium, calcium, magnesium and iron in the organs (root, rhizome, stem, leaf and panicle) of Phragmites australis were determined from March to November, 1975 in Forfar Loch (polytrophic), Balgavies Loch (eutrophic) and Loch of the Lowes (mesotrophic), Scotland. Generally no consistent seasonal changes in the mineral levels were detected for the root, rhizome and panicle. For the stem and leaf, the levels of nitrogen, phosphorus, potassium, calcium and magnesium rose to a peak before declining for the rest of the season. Consistently higher levels of tissue nitrogen, phosphorus, potassium and calcium were found in the Forfar plants over those of Balgavies and Lowes, reflecting the very eutrophic condition in Forfar Loch. The mineral compositions in the reeds in the present study were compared with similar studies in other areas. 相似文献
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T. T. Macan 《Hydrobiologia》1980,70(1-2):159-164
Development of foliage structure in Phragmites australis (Cav.) Trin. ex Steudel stands in three Scottish lochs in 1975 was studied. Both tagged and harvested shoots were utilized to monitor the seasonal changes in the chlorophyll content, net leaf number, rate of shoot elongation, leaf production, leaf fall and leaf area increase, and individual leaf size in the reed-stands from the three study areas. Quantitative measurements of the number of leaf and leaf surface area in 25 cm stratified layers in the shoots were also made during active canopy development from May to August. 相似文献
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Y. B. Ho 《Hydrobiologia》1979,64(3):215-222
Studies were made on the development and production of Phragmites australis (Cav.) Trin. ex Steudel (= Phragmites communis Trin.) stands from Forfar Loch-polytrophic, Balgavies Locheutrophic and Loch of the Lowes-mesotrophic. Differences were detected in the shoot height, shoot dry weight, standing crop biomass, leaf area index, crop growth rate and net efficiency of solar energy conversion among the three lochs. Such differences were partly due to the different nutrient levels of the three locations. The percentage ratio of leaf to shoot weight, leaf area ratio, relative growth rate and net assimilation rate for the reed stands in the three lochs were also calculated and were compared with values from other study areas. 相似文献
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Murray Stewart Leith 《Ethnic and racial studies》2016,39(14):2564-2582
This paper explores Herbert Gans's notion of symbolic ethnicity and his recent assertions that it is effectively at an end and little more than a label. We use research into Scottish-American clan associations to question this assertion and we seek to demonstrate that symbolic ethnicity appears to be alive and well within such diaspora organizations. The paper reports on a series of interviews conducted in 2014 with office bearers and members of clan associations and we use our findings to argue, along with other writers such as Steinberg that, when considering hyphenated ethnicity, it is important not to underestimate the power of the hyphen. 相似文献