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Many plants release allelopathic chemicals that can inhibit germination, growth, and/or survival in neighboring plants. These impacts appear magnified with the invasion of some non-native plants which may produce allelochemicals against which native fauna have not co-evolved resistance. Our objective was to examine the potential allelopathic impact of an invasive non-native shrub/tree on multiple plant species using field observation and experimental allelopathy studies. We surveyed and collected an invasive, non-native tree/shrub (Rhamnus cathartica) at Tifft Nature Preserve (a 107-ha urban natural area near Lake Erie in Buffalo, NY). We also surveyed understory plant communities in the urban forest to examine correlations between R. cathartica abundance and local plant community abundance and richness. We then used experimental mesocosms to test if patterns observed in the field could be explained by adding increased dosages of R. cathartica to soils containing five plant species, including native and non-native woody and herbaceous species. In the highly invaded urban forest, we found that herbaceous cover, shrubs and woody seedlings negatively covaried with R. cathartica basal area and seedlings density. In the mesocosm experiments, R. cathartica resulted in significant decreases in plant community species richness, abundance, and shifted biomass allocation from roots. Our results provide evidence that R. cathartica is highly allelopathic in its invaded range, that R. cathartica roots have an allelopathic effect and that some plant species appear immune. We suggest that these effects may explain the plant’s ability to form dense monocultures and resist competitors, as well as shift community composition with species-specific impacts. 相似文献
964.
Surawski PP Battersby BJ Lawrie GA Ford K Rühmann A Marcon L Kozak D Trau M 《Molecular bioSystems》2008,4(7):774-778
The concept of optically encoding particles for solid phase organic synthesis has existed in the literature for several years. However, there remains a significant challenge to producing particles that are capable of withstanding harsh solvents and reagents whilst maintaining the integrity and range of the optical encoding. In this study, a new generation of fluorescently encoded support particles was used for both solid phase peptide synthesis and on-particle analysis of proteolysis in a multiplexed, flow cytometric assay. The success of the assay was demonstrated through the use of a model protease, trypsin. Our results show that the use of solid supports with high peptide yield, high swellability in water and high penetration of the enzyme into the interior of the particle is not absolutely necessary for proteolysis assays. 相似文献
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966.
Kessner D Chambers M Burke R Agus D Mallick P 《Bioinformatics (Oxford, England)》2008,24(21):2534-2536
SUMMARY: The ProteoWizard software project provides a modular and extensible set of open-source, cross-platform tools and libraries. The tools perform proteomics data analyses; the libraries enable rapid tool creation by providing a robust, pluggable development framework that simplifies and unifies data file access, and performs standard proteomics and LCMS dataset computations. The library contains readers and writers of the mzML data format, which has been written using modern C++ techniques and design principles and supports a variety of platforms with native compilers. The software has been specifically released under the Apache v2 license to ensure it can be used in both academic and commercial projects. In addition to the library, we also introduce a rapidly growing set of companion tools whose implementation helps to illustrate the simplicity of developing applications on top of the ProteoWizard library. AVAILABILITY: Cross-platform software that compiles using native compilers (i.e. GCC on Linux, MSVC on Windows and XCode on OSX) is available for download free of charge, at http://proteowizard.sourceforge.net. This website also provides code examples, and documentation. It is our hope the ProteoWizard project will become a standard platform for proteomics development; consequently, code use, contribution and further development are strongly encouraged. 相似文献
967.
Question: How does regular management burning of a northern, Calluna vulgaris‐dominated heathland affect the lichen diversity at the patch and landscape scale? Location: Mar Lodge Estate, Scottish Highlands, United Kingdom. Methods: 26 fire sites of different ages and 11 long‐term unburnt stands were surveyed to create a chronosequence of changing lichen diversity following burning. Data were analysed graphically, with a GLM and using a CCA. Results: Though the immediate effect of fire was to significantly reduce lichen diversity, it generally recovered within 20 years. There was a significant difference in the population dynamics between wet and dry moorland areas with terricolous lichens in the former site being replaced by pleurocarpous mosses. Older stands, unburnt for 25 years or more, generally had lower diversity than stands 10 to 15 years old. Changes in lichen diversity and community composition can be attributed to the development of Calluna stand structure following burning. Conclusions: Fire can be seen to play an important role in maintaining the diversity of lichens in heathland areas by providing a variety of stand‐structures and ages across the landscape that favours the development of greater beta‐diversity. 相似文献
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A mouse to human search for plasma proteome changes associated with pancreatic tumor development 总被引:1,自引:0,他引:1
Faca VM Song KS Wang H Zhang Q Krasnoselsky AL Newcomb LF Plentz RR Gurumurthy S Redston MS Pitteri SJ Pereira-Faca SR Ireton RC Katayama H Glukhova V Phanstiel D Brenner DE Anderson MA Misek D Scholler N Urban ND Barnett MJ Edelstein C Goodman GE Thornquist MD McIntosh MW DePinho RA Bardeesy N Hanash SM 《PLoS medicine》2008,5(6):e123