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21.
BRANT C. FAIRCLOTH GWEN P. KELLER C. JOSEPH NAIRN WILLIAM E. PALMER JOHN P. CARROLL PATRICIA ADAIR GOWATY 《Molecular ecology resources》2006,6(3):646-649
We describe primers and polymerase chain reaction (PCR) conditions to amplify 18 tetranucleotide microsatellite DNA loci in eastern bluebirds (Sialia sialis). The primers were tested using individuals from two study sites in Georgia and South Carolina. Among individuals from the Georgia population (n = 23), the primer pairs developed in this study yielded an average of 6.6 alleles per locus (range 2–12), an average observed heterozygosity of 0.56 (range 0.24–0.96) and an average polymorphic information content of 0.65 (range 0.3–0.86). Among individuals from the South Carolina population (n = 19), the primer pairs yielded an average of 5.8 alleles per locus (range 2–9), an average observed heterozygosity of 0.56 (range 0.05–0.86) and an average polymorphic information content of 0.63 (range 0.29–0.83). 相似文献
22.
van Gool CJ van Houwelingen AC Hornstra G 《The Journal of nutritional biochemistry》2000,11(11-12):543-547
Phenylketonuric patients are on a special diet that lacks certain essential fatty acids. This study evaluates the essential fatty acid status of a group of phenylketonuric patients in the Netherlands undergoing dietary treatment. To this end, the essential fatty acid status of nine phenylketonuria patients was studied. On the basis of age and gender, two control subjects were selected for each patient. The essential fatty acid composition of duplicate food portions and the essential fatty acid status of plasma and erythrocytes were analyzed. Phenylketonuria subjects had a different essential fatty acid profile from their peers, especially concerning the n-3 fatty acids. N-6 and n-3 fatty long-chain polyenes were hardly consumed by phenylketonuria subjects, in contrast to the control subjects. Linoleic acid, on the other hand, was consumed in significantly higher amounts by phenylketonuria subjects and made up about 40% of their daily fat consumption. The essential fatty acid consumption pattern of the phenylketonuria subjects is mirrored by the essential fatty acid concentrations in blood. The essential fatty acid status of the phenylketonuric diet should be improved in order to prevent deficiency in n-3 fatty acids. 相似文献
23.
AMY NICOLA SUSAN PALMER 《Austral ecology》2012,37(1):110-124
Many species are aggregated at some spatial scale but for some species, due to habitat or behaviour, aggregation can be difficult to assess quantitatively. Here, aggregation of chiton species (Polyplacophora; Neoloricata; Ischnochitonina; Ischnochitonidae; Ischnochitoninae; Ischnochiton) living under boulders in intertidal boulder fields was investigated at several relatively small spatial scales. Closely related species were found to be aggregated at the level of individual boulders, but evidence for grouping at the larger scale of patches of boulders varied. When organisms are mobile, dispersal can have an important influence on spatial patterns. Some organisms, such as marine invertebrates, have a highly dispersive larval phase that can influence spatial patterns of adults, particularly where the adult is sessile or relatively sedentary. Aggregation was compared in two species to test whether different modes of larval development influence spatial pattern. There was some evidence that species with a planktonic larva were even more aggregated than expected, in contrast to predictions based on this mode of development. Both types of larval development (planktonic and non‐planktonic) produce larvae with short development times in these species, so one possible explanation for the grouping habit of these chitons is that they do not disperse, at all, from their natal boulder. The complexity of the boulder field habitat and the cryptic behaviour of these chitons may also contribute to a lack of dispersal. A simple application of a genetic method indicated, however, that philopatry at this scale is unlikely. 相似文献
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Faunal distribution and colonization strategy in a Middle Ordovician hardground community 总被引:2,自引:0,他引:2
TIMOTHY J. PALMER CAROLINE D. PALMER 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1977,10(3):179-199
The attached fauna of one of the many hardgrounds from the Galena Group (Trentonian Substage) of the Upper Mississippi Valley is described. The fauna is composed of three principal elements, viz. (1) borers, including Cicatricula retiformis ichnogen. et ichnosp. nov., (2) pelmatozoans with encrusting holdfasts, and (3) bryozoans. Analysis of the distribution of members of each population on the hardground shows that most are strongly aggregated. The nature of, and reasons for, such aggregations are considered in the light of comparable Recent shallow-water marine populations. The community on this hardground, and those on other Galena Group hardgrounds, are immature. This is a consequence of frequent and damaging scour, which these organisms were poorly adapted to resist. 相似文献
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Sampling for aphids by traps and by crop inspection 总被引:1,自引:0,他引:1
The catches of thirty aphid genera and species during 3 years in a suction trap at 40 ft and on a yellow cylindrical sticky trap at 5 ft at Rothamsted and Broom's Barn are tabulated. Suction-trap catches were the more consistent but both were more effective at recording the first seasonal immigration of Myzuspersicae (Sulz.) and Aphis fabae Scop, than the British Sugar Corporation crop-inspection scheme. The catches show the differential attraction to yellow by different species, the effects of local vegetation, and the seasonal distribution of aphids that are crop pests or potential vectors of viruses. 相似文献