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971.
The restoration potential of Sweetgrass (Anthoxanthum nitens (Weber) Y. Schouten & Veldkamp) was evaluated through a field experiment conducted on Kanatsiohareke, a Mohawk farm, and at the LaFayette Experiment Station near Syracuse, New York. The effects of competition reduction and two cover crops on Sweetgrass reestablishment success were examined. Sweetgrass was planted under four treatments: Sweetgrass alone; with existing, old‐field vegetation; with a cover crop of Hairy vetch (Vicia villosa); and with a cover crop of Annual (Italian) ryegrass (Lolium multiflorum). The experiment consisted of five replicates of the four treatments at both LaFayette and Kanatsiohareke. Sweetgrass biomass, height, reproduction rate, and survivorship were greatest in plots that were weeded to eliminate competition and in plots with Hairy vetch as a cover crop. A cover crop of Annual ryegrass resulted in reduced Sweetgrass growth and reproduction. The results of this field experiment indicate that there is great restoration potential for Sweetgrass because it is easily transplanted and reproduces vigorously. For 2.25‐m2 plots, Hairy vetch is an effective cover crop for Sweetgrass. Planting the Sweetgrass with Hairy vetch generated properties of the grass that are desired by basketmakers, such as abundance and tall blades. This technique also allowed for a relatively non–labor intensive method of cultivation. Reestablishment of Sweetgrass offers the members and visitors of Kanatsiohareke the means to continue to use the plant, strengthen traditional practices associated with Sweetgrass, and benefit economically by selling baskets and medicine made with Sweetgrass. 相似文献
972.
Robin Welcomme 《Journal of fish biology》2005,66(1):292-293
973.
Resistance to Alpha/Beta Interferons Correlates with the Epizootic and Virulence Potential of Venezuelan Equine Encephalitis Viruses and Is Determined by the 5′ Noncoding Region and Glycoproteins 下载免费PDF全文
Deborah R. Spotts Robin M. Reich Mohammed A. Kalkhan Richard M. Kinney John T. Roehrig 《Journal of virology》1998,72(12):10286-10291
We compared the alpha/beta interferon (IFN-α/β) sensitivities of the TC-83 vaccine strain and 24 enzootic and epizootic Venezuelan equine encephalitis (VEE) isolates. The IFN-resistant or -sensitive phenotype correlated well with epizootic or enzootic potential. IFN-α/β resistance of Trinidad donkey (TRD) virus correlated with virulence determinants in the 5′ noncoding region and glycoproteins. Infection of mice lacking a functional IFN system with the IFN-sensitive TC-83 virus resulted in disease equivalent to that produced by the virulent, IFN-resistant TRD virus, further demonstrating that IFN resistance contributes to VEE virus virulence and is a biological marker of epizootic potential. 相似文献
974.
Optimal outgroup analysis 总被引:8,自引:0,他引:8
James Lyons-Weiler Guy A. Hoelzer Robin J. Tausch 《Biological journal of the Linnean Society. Linnean Society of London》1998,64(4):493-511
We present and critically examine a statistical criterion for the selection of outgroup taxa for rooting evolutionary trees. The criterion is the amount of phylogenetic signal for the ingroup when the states of the candidate outgroup taxa are assumed to be plesiomorphic relative to the ingroup for the purpose of measuring plesiomorphy content of the outgroup taxon. A statistical measure of rooted, ingroup signal was subjected to a suite of critical tests which indicate that it provides a proxy measure of plesiomorphy content. As the evolutionary distance between the ingroup ancestral node and outgroup taxa increases, the tree-independent measure of signal decreases, tracking the decay in plesiomorphy content and the increase in convergence to the ingroup states. We show that a priori generalizations about optimal outgroup taxon sampling strategies are likely to be misleading, and that testing for the suitability of available outgroup taxon sampling in specific instances is warranted. Software for optimal outgroup analysis is available. 相似文献
975.
S Ait-Si-Ali S Ramirez P Robin D Trouche A Harel-Bellan 《Nucleic acids research》1998,26(16):3869-3870
976.
Summary
Olpidiopsis antithamnionis n. sp. (Oomycetes, Olpidiopsidaceae) parasitic on Antithamnion floccosum (O. F. Müll.) Kleen (Rhodophyta, Ceramiaceae) is described from three sites in Newfoundland, Canada, and from culture.Axial cells of the main and determinate branches of the host are the primary sites of fungal attack, although tetrasporangia and rhizoidal cells are also susceptible. Successful re-infection of A. floccosum was achieved in the laboratory although A. boreale and the trailliella-phase of Bonnemaisonia hamifera, both occurring with A. floccosum in the field, were immune. Regeneration of the host cells was observed, a phenomenon not previously reported in the fungal parasitism of other filamentous benthic marine algae.Studies in Biology from Memorial University of Newfoundland No. 256. 相似文献
977.
Robin D. Veldsema-Currie 《The Biochemical journal》1973,135(4):673-682
1. An enzyme similar to mammalian acetylcholinesterase is found in high activity in the nervous tissue of Palaemonetes varians, i.e. eyes plus stalks, brain, suboesophageal ganglion and ventral cord. Acetylcholinesterase is also found associated with the abdominal muscles. Multiple enzyme forms are found in extracts of nervous tissues and muscles by electrophoresis and isoelectric focusing. 2. Cholinesterase is present in high activity in the stomatogastric system of P. varians. Three electrophoretically separable forms are found, having isoelectric points at pH4.2, 4.5 and 5.4. 3. Approx. 50% of the total acetylcholinesterase activity, approx. 80% of the choline acetyltransferase activity and 100% of the acetylcholine equivalents are found associated with the nervous tissue. Among the tissues examined, eyes plus stalks were the richest source of both choline acetyltransferase and acetylcholine equivalents. Suboesophageal ganglion and brain also contained large amounts of these components. 4. The distribution of these components could support the function of acetylcholine as a central and/or sensory transmitter in P. varians. 相似文献
978.
Low-Molecular-Weight RNAs of Murine Sarcoma Virus: Comparative Studies of Free and 70S RNA-Associated Components 总被引:4,自引:4,他引:0 下载免费PDF全文
R. Emanoil-Ravicovitch C. J. Larsen M. Bazilier J. Robin J. Périès M. Boiron 《Journal of virology》1973,12(6):1625-1627
Several low-molecular-weight RNAs were released from mouse leukemia sarcoma virus 70S RNA under conditions of thermal denaturation. One of them, the 70S-associated 8S RNA, exhibits a number of structural properties characteristic of a previously described free viral 8S RNA. This similarity was revealed by polyacrylamide gel electrophoresis and nucleotide composition. 相似文献
979.
980.