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101.
Sergey I. Zhadanov Matthew C. Dulik Michael Markley George W. Jennings Jill B. Gaieski George Elias Theodore G. Schurr 《American journal of physical anthropology》2010,142(4):579-589
The name “Wampanoag” means “Eastern People” or “People of the First Light” in the local dialect of the Algonquian language. Once extensively populating the coastal lands and neighboring islands of the eastern United States, the Wampanoag people now consist of two federally recognized tribes, the Aquinnah and Mashpee, the state‐recognized Seaconke Wampanoag tribe, and a number of bands and clans in present‐day southern Massachusetts. Because of repeated epidemics and conflicts with English colonists, including King Philip's War of 1675–76, and subsequent colonial laws forbidding tribal identification, the Wampanoag population was largely decimated, decreasing in size from as many as 12,000 individuals in the 16th century to less than 400, as recorded in 1677. To investigate the influence of the historical past on its biological ancestry and native cultural identity, we analyzed genetic variation in the Seaconke Wampanoag tribe. Our results indicate that the majority of their mtDNA haplotypes belongs to West Eurasian and African lineages, thus reflecting the extent of their contacts and interactions with people of European and African descent. On the paternal side, Y‐chromosome analysis identified a range of Native American, West Eurasian, and African haplogroups in the population, and also surprisingly revealed the presence of a paternal lineage that appears at its highest frequencies in New Guinea and Melanesia. Comparison of the genetic data with genealogical and historical information allows us to reconstruct the tribal history of the Seaconke Wampanoag back to at least the early 18th century. Am J Phys Anthropol 142:579–589, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
102.
Seema Joshi Gopal Singh Bisht Diwan S. Rawat Rita Kumar Santosh Pasha 《生物化学与生物物理学报:生物膜》2010,1798(10):1864-1875
Cationic antimicrobial peptides (CAMPs) are novel candidates for drug development. Here we describe design of six short and potent CAMPs (SA-1 to SA-6) based on a minimalist template of 12 residues H+HHG+HH+HH+NH2 (where H: hydrophobic amino acid and +: charged hydrophilic amino acid). Designed peptides exhibit good antibacterial activity in micro molar concentration range (1-32 μg/ml) and rapid clearance of Gram-positive and Gram-negative bacterial strains at concentrations higher than MIC. For elucidating mode of action of designed peptides various biophysical studies including CD and Trp fluorescence were performed using model membranes. Further based on activity, selectivity and membrane bound structure; modes of action of Trp rich peptide SA-3 and template based peptide SA-4 were compared. Calcein dye leakage and transmission electron microscopic studies with model membranes exhibited selective membrane active mode of action for peptide SA-3 and SA-4. Extending our work from model membranes to intact E. coli ATCC 11775 in scanning electron micrographs we could visualize different patterns of surface perturbation caused by peptide SA-3 and SA-4. Further at low concentration rapid translocation of FITC-tagged peptide SA-3 into the cytoplasm of E. coli cells without concomitant membrane perturbation indicates involvement of intracellular targeting mechanism as an alternate mode of action as was also evidenced in DNA retardation assay. For peptide SA-4 concentration dependent translocation into the bacterial cytoplasm along with membrane perturbation was observed. Establishment of a non specific membrane lytic mode of action of these peptides makes them suitable candidates for drug development. 相似文献
103.
104.
105.
Aim To investigate the distribution of local flowering plant species richness in areas surrounding American universities.
Methods Species richness in university counties was compared with neighbouring counties. Data were derived from Synthesis of the North American Flora ( http://www.phylosystems.com/prepublication ). Probabilities of the resultant distribution were calculated, and the results were also simulated.
Results In almost every case there were more species reported in the university county than in its neighbours. Several possible explanations were considered. We conclude that the key element is the presence of botanists in these counties who have, apparently, paid more attention to plants near at hand, and found more species of them there.
Main conclusions Ecologists must be aware that numerical data that appear very solid, collected over many decades, may represent not only the qualities of 'nature' but also something of the collectors of the data. 相似文献
Methods Species richness in university counties was compared with neighbouring counties. Data were derived from Synthesis of the North American Flora ( http://www.phylosystems.com/prepublication ). Probabilities of the resultant distribution were calculated, and the results were also simulated.
Results In almost every case there were more species reported in the university county than in its neighbours. Several possible explanations were considered. We conclude that the key element is the presence of botanists in these counties who have, apparently, paid more attention to plants near at hand, and found more species of them there.
Main conclusions Ecologists must be aware that numerical data that appear very solid, collected over many decades, may represent not only the qualities of 'nature' but also something of the collectors of the data. 相似文献
106.
ABSTRACT Band-recovery and wing-collection survey data have the potential to provide information on American woodcock (Scolopax minor) fall migration ecology in the Central Region of the United States, yet researchers have not recently analyzed these extensive data sets. We analyzed all direct recoveries of woodcock banded in Michigan, Minnesota, and Wisconsin, USA, as well as wing-collection survey data, to determine the progression of fall migration, the migration direction, and the final destination of woodcock migrating from these states. We did not observe migration initiation based on band recoveries until late October and early November, with most migration occurring during November. Wing-receipt data showed a similar trend, with most change in mean receipt latitude occurring from 1 November to 5 December. During November, wing receipts were spread through the entire Central Region. By 15–31 December, 92% (n = 26) of band recoveries were on the wintering grounds (south of latitude 33°N). Most banded woodcock from Michigan, Minnesota, and Wisconsin wintered in Louisiana, USA. Woodcock banded in these states will be exposed to harvest for most of the hunting season because they remain in these states through November. If the population status of local birds is a concern, managers should consider this migration pattern when setting season dates. 相似文献
107.
South American leaf blight of the rubber tree (Hevea spp.): new steps in plant domestication using physiological features and molecular markers 总被引:1,自引:0,他引:1
Lieberei R 《Annals of botany》2007,100(6):1125-1142
BACKGROUND: Rubber trees (Hevea spp.) are perennial crops of Amazonian origin that have been spread over the whole tropical belt to guarantee worldwide production of natural rubber. This crop plant has found its place in many national economies of producing countries, and although its domestication by selection of suitable genotypes was very slow, it contributes a lot to the welfare of small farmers worldwide. Its development is limited by severe diseases. In South America, the main fungal disease of rubber trees is the South American leaf blight (SALB) caused by the ascomycete Microcyclus ulei. This fungus inhibits natural rubber production on a commercial scale in South and Central America. SCOPE: The disease is still restricted to its continent of origin, but its potential to be distributed around the world rises with every transcontinental airline connection that directly links tropical regions. The need to develop control measures against the disease is an urgent task and must be carried out on an international scale. All control efforts so far taken since 1910 have ended in a miserable failure. Even the use of modern systemic fungicides and use of greatly improved application techniques have failed to prevent large losses and dieback of trees. The results of research dealing with both the disease and the pathosystem over more than 50 years are summarized and placed into perspective. FUTURE PROSPECTS: A detailed knowledge of this host-pathogen combination requires understanding of the dynamics of Hevea leaf development, the biochemical potential for cyanide liberation, and molecular data for several types of resistance factors. Resolution of the Hevea-SALB problem may serve as a model for future host-pathogen studies of perennial plants requiring a holistic approach. 相似文献
108.
Knut E. Jørstad P. A. Prodohl A.-L. Agnalt M. Hughes E. Farestveit A. F. Ferguson 《Hydrobiologia》2007,590(1):103-114
American lobsters (Homarus americanus H. Milne Edwards, 1837) are imported live to Europe and should according regulations be kept in land-based tanks until sold. In spite of the strict regulations aimed specifically at preventing the introduction of this species into the NE Atlantic, several specimens of H. americanus have been captured in the wild, especially in Oslofjord, Norway since 1999. One of the great concerns is interbreeding between the introduced American species and the local European lobster, H. gammarus (Linnaeus, 1758). For this reason an awareness campaign was launched in 2000 focusing on morphologically “unusual” lobsters caught in local waters. Morphological characters have been based on colour and sub-ventral spines on the rostrum. Two samples of H. americanus were used for comparisons, as well as samples of European lobster from Oslofjord collected in 1992. Previous genetic analyses (allozymes, mtDNA and microsatellite DNA) have demonstrated that the American lobster is distinct from its European counterpart, with several additional alleles at many loci in addition to different allelic frequency distribution of alleles of “shared” alleles. During the present study, thirteen microsatellite loci were tested in the initial screening, and the three most discriminating loci (Hgam98, Hgam197b and Hgam47b) were used in a detailed comparison between the two species. A total of 45 unusual lobsters were reported captured from Ålesund (west) to Oslofjord (southeast) from 2001 to 2005 and these were analysed for the three microsatellite loci. Nine specimens were identified as American lobsters. Comparisons between morphological and genetic characteristics revealed that morphological differences are not reliable in discrimination the two species, or to identify hybrids. Further, some loci display almost no overlapping in allele frequency distribution for the reference samples analysed, thus providing a reliable tool to identify hybrids. 相似文献
109.
Successful biological control of mist flower (Ageratina riparia) in New Zealand: Agent establishment, impact and benefits to the native flora 总被引:1,自引:0,他引:1
Jane Barton Simon V. Fowler Alison F. Gianotti Chris J. Winks Maarten de Beurs Greg C. Arnold Guy Forrester 《Biological Control》2007,40(3):370-385
The white smut fungus (Entyloma ageratinae) and the gall fly (Procecidochares alani) were released in New Zealand in 1998 and 2001 respectively to suppress mist flower (Ageratina riparia). The fungus established and spread rapidly, crossing 80 km of sea to Great Barrier Island within 2 years. The mean number of P. alani galls increased exponentially to 1.96/stem at release sites, but dispersal was slow. The impact of the biocontrol agents was monitored once annually from 1998/99 to 2003/04, at up to 51 sites in the North Island. The mean percentage of live leaves infected with fungus rapidly reached nearly 60%. Maximum plant height declined significantly. In heavy infestations, mean percentage cover of mist flower declined from 81 to 1.5%. Galls were only recorded towards the end of the impact study, and at low mean numbers. As mist flower declined, the species richness and mean percentage cover of native plants increased. In contrast, the species richness and mean percentage cover of exotic plants (excluding mist flower) did not change significantly. Many plant species colonizing the plots were important native mid- or late-successional shrubs or trees. With few exceptions, the exotic plant species common in the plots were not weeds that appeared to threaten native forest habitats. There was only a weak “replacement weed effect” from the potentially serious invader African club moss (Selaginella kraussiana). These data, together with reports of reduced threats to rare endemic plants from mist flower, suggest this rapid, well-monitored weed biocontrol program was very successful. 相似文献
110.
Koepfli KP Gompper ME Eizirik E Ho CC Linden L Maldonado JE Wayne RK 《Molecular phylogenetics and evolution》2007,43(3):1076-1095
The Procyonidae (Mammalia: Carnivora) have played a central role in resolving the controversial systematics of the giant and red pandas, but phylogenetic relationships of species within the family itself have received much less attention. Cladistic analyses of morphological characters conducted during the last two decades have resulted in topologies that group ecologically and morphologically similar taxa together. Specifically, the highly arboreal and frugivorous kinkajou (Potos flavus) and olingos (Bassaricyon) define one clade, whereas the more terrestrial and omnivorous coatis (Nasua), raccoons (Procyon), and ringtails (Bassariscus) define another clade, with the similar-sized Nasua and Procyon joined as sister taxa in this latter group. These relationships, however, have not been tested with molecular sequence data. We examined procyonid phylogenetics based on combined data from nine nuclear and two mitochondrial gene segments totaling 6534bp. We were able to fully resolve relationships within the family with strongly supported and congruent results from maximum parsimony, maximum likelihood, minimum evolution, and Bayesian analyses. We identified three distinct lineages within the family: a (Nasua, Bassaricyon) clade, a (Bassariscus, Procyon) clade, and a Potos lineage, the last of which is sister to the other two clades. These findings, which are in strong disagreement with prior fossil and morphology-based assessments of procyonid relationships, reemphasize the morphological and ecological flexibility of these taxa. In particular, morphological similarities between unrelated genera possibly reflect convergence associated with similar lifestyles and diets rather than ancestry. Furthermore, incongruence between the molecular supermatrix and a morphological character matrix comprised mostly of dental characters [Baskin, J.A., 2004. Bassariscus and Probassariscus (Mammalia, Carnivora, Procyonidae) from the early Barstovian (Middle Miocene). J. Vert. Paleo. 24, 709-720] may be due to non-independence among atomized dental characters that does not take into account the high developmental genetic correlation of these characters. Finally, molecular divergence dating analyses using a relaxed molecular clock approach suggest that intergeneric and intrageneric splits in the Procyonidae mostly occurred in the Miocene. The inferred divergence times for intrageneric splits for several genera whose ranges are bisected by the Panamanian Isthmus is significant because they suggest diversification well precedes the Great American Interchange, which has long been considered a primary underlying mechanism for procyonid evolution. 相似文献