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During the last decade much information has been produced about the zooplankton communities in southern Chile; however, most of this is related to the crustacean assemblages. The present communication examines the spatial and temporal distribution of rotifer assemblages and their relation to the environmental variables during one-year period in four Araucanian lakes. A total of 19 species was found in these oligotrophic lakes. Keratella cochlearis, Synchaeta stylata, Trichocerca porcellus, Conochilus unicornis and Collotheca pelagica were widespread, and seven species exhibited a more restricted distribution among the lakes. Species richness varied from 6 to 12; similarly, one or two dominant species usually accounted for more than 80% of the total annual abundance. Similar dominant species occurred in two lakes, but their maximum peaks of abundance differed in time; in the remaining lakes the most important species were different. Calculated rotifer diversity showed a fluctuating pattern, with low values during the year in three lakes, and high ones in Lake Llanquihue. Species diversity was significantly related to species richness in all lakes. Discriminant analysis based on the occurrence and abundances of species throughout the year revealed that the rotifer assemblage in Lake Llanquihue was different from that in the rest of the Araucanian lakes. Furthermore, the same analysis using environmental variables showed that this lake is clearly discriminated from the others on the basis of the ionic composition of the water (i.e. Cl–, Na+, Mg2+). Rotifer abundances in these lakes were significantly influenced by a number of abiotic variables, including those related to water ionic composition. These relationships may imply that the small differences in chemical characteristics of these lakes influence the structure of the rotifer community. 相似文献
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Diego Rey Carlos Parga-Lozano Juan Moscoso Cristina Areces Mercedes Enriquez-de-Salamanca Mercedes Fernández-Honrado Sedeka Abd-El-Fatah-Khalil Javier Alonso-Rubio Antonio Arnaiz-Villena 《Molecular biology reports》2013,40(7):4257-4267
Amerindian Mapuche (Araucanians) are now living in Chile and Argentina at both sides of Andean Mountains. They are anthropologically and genetically different from southernmost South America Patagonian Amerindians. Most of the HLA alleles found in our Mapuche sample are frequent or very frequent in North and South America Amerindians: (1) Class I: A*02:01, A*03:01, A*68:01, B*39:09, B*51:01, (2) Class II: DRB1*03:01, DRB1*04:03, DRB1*07:01, DRB1*08:02, DRB1*14:02, DRB1*16:02. One of the nine most frequent extended haplotypes seems to be from European origin, suggesting the existence of a degree of admixture with Europeans in our Mapuche sample. It has been calculated of about 11 % admixture. Three of the extended haplotypes are also found in other Amerindians and five of them are newly found in Mapuche Amerindians: A*68:01-B*39:09-DRB1*08:02-DQB1*04:02; A*68:01-B*51:01-DRB1*04:03-DQB1*03:02; A*29:01-B*08:01-DRB1*03:01-DQB1*02:01; A*02:01-B*15:01-DRB1*04:03-DQB1*03:02; A*33:01-B*14:02-DRB1*07:01-DQB1*03:03. The medical importance of calculating HLA profile is discussed on the diagnostic (HLA and disease) and therapeutical bases of HLA pharmacogenomics and on the construction of a virtual transplantation HLA list profile. Also, anthropological conclusions are drawn. 相似文献
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《Plains anthropologist》2013,58(97):245-248
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《Plains anthropologist》2013,58(69):225-230
AbstractData collected in 1972 from three communities in Nebraska, through intensive interviewing of women of childbearing age, are summarized. Rural-urban contrasts in variables related to population growth indicate that Omaha women are having many wanted children (4.5 by age 34). City residents have (and want) families at least as large as those had (and wanted) by reservation residents. Large families are not explained by (a) religious factors; (b) greater desire for children of one sex, i.e. boys, (c) ignorance or disapproval of birth control or (d) rural residence. Explanation appears to lie partly in large-family values derived from an Omaha past laced with disastrous epidemics which struck six times in the 19th century, killing from 50 to 1500 persons or from 5% to 75% of the tribe. 相似文献
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The phenotypes of 256 cats seen in Omaha, Nebraska, during the summer of 1983 were recorded and compared to those of other midcontinental USA cat populations. When cats that were "pure-bred," or derived from pure breeds, were excluded, random breeding at the O locus was confirmed and mutant allele frequencies were: O = 0.352, a = 0.813, tb = 0.354, d = 0.525, I = 0.369, S = 0.197, and W = 0.039. Siamese and Himalayan cats constituted 10.9 percent of the total sample (cs = 0.342), but analysis suggests that they are not randomly mating with the general population. Mutant allele frequencies of Omaha cats are more similar to those of cats in Champaign, Illinois, than to those of St. Louis, suggesting that an overland route was more important than a river route in founding the Omaha cat population. 相似文献
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《Plains anthropologist》2013,58(62):257-270
AbstractWhen first known to Whites, the Omaha were east and north of the Missouri River; they are not reported west of that stream until the late 18th century. At that time they occupied parts of what is now northeastern Nebraska, with their major villages and hunting territory in that area. Trade influences, direct and indirect, probably first reached them in 1700. Contact with the Spanish and later French was principally economic, but there were accompanying major changes in political organization, especially in the authority of chiefs, even before the time of Lewis and Clark. 相似文献
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Martel-Cea Alejandra Astorga Giselle Andrea Hernández Marjorie Caputo Luciano Abarzúa Ana María 《Hydrobiologia》2021,848(10):2551-2568
Hydrobiologia - Detailed studies of Chironomidae fauna can yield a reliable tool to evaluate the effects of climatic change and anthropogenic disturbances over freshwater ecosystems. Using modern... 相似文献
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Fragmentary cranial remains of a child from a commingled burial in a historic Omaha Cemetery (AD 1780–1800) exhibit bony fusion between the frontal, parietals, and sphenoid. The child's remains are consistent with a developmental age between newborn and 6 months postnatal. Radiological and morphological analyses confirm that this individual exhibits osteological signs pathognomic of bicoronal sutural synostosis, including deformation of the lateral orbital margin. This case, although fragmentary, significantly augments other archaeological cases of coronal synostosis reported in the literature. In addition, an extremely large bregmatic fontanel, expanded anterior cranial fossa, and bossed forehead compared with undeformed individuals suggest the child also suffered from increased intracranial pressure perhaps related to an associated hydrocephaly. Despite the deformity, the remains of this child were treated in much the same manner as other infant remains from the site, including the presence of red mercury pigment on the skeletal remains. Am J Phys Anthropol 105:369–376, 1998. © 1998 Wiley-Liss, Inc. 相似文献
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The analysis of skeletal remains of Omaha Indians buried between AD 1780 and 1820 indicated that lead was incorporated in cortical bone. The diagenetic or biogenetic origin of the lead was evaluated by examination of lead isotope ratios of the bones and artifacts, and comparison of lead concentrations in burial soils with those of the bones. The isotopic values of the lead artifacts demonstrate that the lead was mined in the Missouri region. Although the isotope ratios in the bones are not identical with that from the lead artifacts, there is a strong relationship between them. This finding indicates that the lead in the bone was at least partly derived from the artifacts. Because lead artifacts rarely accompanied the burials but lead was ubiquitous in the bones, we suggest a biogenetic origin for the lead. There is also the possibility that some of the lead may have been derived from pigments applied to the corpse during mortuary ritual. 相似文献