Population dynamics of ambient and altered earthworm communities in row-crop agroecosystems in the Midwestern U.S. The 7th international symposium on earthworm ecology · Cardiff · Wales · 2002     

William D. Shuster  Martin J. Shipitalo  Patrick J. Bohlen  Scott Subler  Clive A. Edwards 《Pedobiologia》2003,47(5-6):825-829

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The trophic diversity of nematode communities in soils treated with vermicompost The 7th international symposium on earthworm ecology · Cardiff · Wales · 2002     

Norman Q. Arancon  Paola Galvis  Clive Edwards  Erdal Yardim 《Pedobiologia》2003,47(5-6):736-740

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Soil Leachate Responses During 10 Years of Induced Whole-Watershed Acidification     

Edwards  Pamela J.  Kochenderfer  James N.  Coble  Dean W.  Adams  Mary Beth 《Water, air, and soil pollution》2002,140(1-4):99-118

Soil solution was collected from zero-tension lysimeters for 10 yr on two small central Appalachian watersheds in West Virginia, U.S.A. Ammonium sulfate fertilizer was applied to onecatchment 3 times per year during each year. The other watershedwas used as a reference to account for ambient baseline conditions. Ca and Mg concentrations collected below the A- andB-horizons of the treated watershed increased and then decreasedover time as a result of the treatment. By contrast, Ca and Mgconcentrations in the C-horizon continued to increase throughoutthe study period. The depletion in Ca and Mg that occurred inthe upper levels apparently occurred due to charge pairing andleaching of those base cations with NO₃ and SO₄. Theprogressively greater amounts of Ca and Mg carried through thesoil with these acid anions provided their continued increasingconcentrations in the C-horizon. NO₃ concentrations increased progressively with depth due to both the assimilationof NO₃ by vegetation and microorganisms in the upper soillayers and leaching of NO₃ into deeper soils by mesoporeflow. NO₃ became a more important ion over time with respectto pairing and leaching with base cations because its concentrations continued to increase in all soil layers, whereasSO₄ became retained in all soil layers after after severalyears of treatment, presumably induced by adsorption from increasing SO₃ concentrations.  相似文献   

Bioencapsulation of metronidazole in adult brine shrimp (Artemia sp.)     

Allender MC  Kastura M  George R  Bulman F  Yarbrough J  Cox S 《Journal of zoo and wildlife medicine》2011,42(2):241-246

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Hybridization between Brassica napus and B. rapa on a national scale in the United Kingdom     

Wilkinson MJ  Elliott LJ  Allainguillaume J  Shaw MW  Norris C  Welters R  Alexander M  Sweet J  Mason DC 《Science (New York, N.Y.)》2003,302(5644):457-459

Measures blocking hybridization would prevent or reduce biotic or environmental change caused by gene flow from genetically modified (GM) crops to wild relatives. The efficacy of any such measure depends on hybrid numbers within the legislative region over the life-span of the GM cultivar. We present a national assessment of hybridization between rapeseed (Brassica napus) and B. rapa from a combination of sources, including population surveys, remote sensing, pollen dispersal profiles, herbarium data, local Floras, and other floristic databases. Across the United Kingdom, we estimate that 32,000 hybrids form annually in waterside B. rapa populations, whereas the less abundant weedy populations contain 17,000 hybrids. These findings set targets for strategies to eliminate hybridization and represent the first step toward quantitative risk assessment on a national scale.  相似文献   

One-third of reef-building corals face elevated extinction risk from climate change and local impacts     

Carpenter KE  Abrar M  Aeby G  Aronson RB  Banks S  Bruckner A  Chiriboga A  Cortés J  Delbeek JC  Devantier L  Edgar GJ  Edwards AJ  Fenner D  Guzmán HM  Hoeksema BW  Hodgson G  Johan O  Licuanan WY  Livingstone SR  Lovell ER  Moore JA  Obura DO  Ochavillo D  Polidoro BA  Precht WF  Quibilan MC  Reboton C  Richards ZT  Rogers AD  Sanciangco J  Sheppard A  Sheppard C  Smith J  Stuart S  Turak E  Veron JE  Wallace C  Weil E  Wood E 《Science (New York, N.Y.)》2008,321(5888):560-563

The conservation status of 845 zooxanthellate reef-building coral species was assessed by using International Union for Conservation of Nature Red List Criteria. Of the 704 species that could be assigned conservation status, 32.8% are in categories with elevated risk of extinction. Declines in abundance are associated with bleaching and diseases driven by elevated sea surface temperatures, with extinction risk further exacerbated by local-scale anthropogenic disturbances. The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds that of most terrestrial groups. The Caribbean has the largest proportion of corals in high extinction risk categories, whereas the Coral Triangle (western Pacific) has the highest proportion of species in all categories of elevated extinction risk. Our results emphasize the widespread plight of coral reefs and the urgent need to enact conservation measures.  相似文献   

Combined action of PHD and chromo domains directs the Rpd3S HDAC to transcribed chromatin   总被引：2，自引：0，他引：2  

Li B  Gogol M  Carey M  Lee D  Seidel C  Workman JL 《Science (New York, N.Y.)》2007,316(5827):1050-1054

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Complement factor H polymorphism and age-related macular degeneration   总被引：1，自引：0，他引：1  

Edwards AO  Ritter R  Abel KJ  Manning A  Panhuysen C  Farrer LA 《Science (New York, N.Y.)》2005,308(5720):421-424

Age-related macular degeneration (AMD) is a common, late-onset, and complex trait with multiple risk factors. Concentrating on a region harboring a locus for AMD on 1q25-31, the ARMD1 locus, we tested single-nucleotide polymorphisms for association with AMD in two independent case-control populations. Significant association (P = 4.95 x 10(-10)) was identified within the regulation of complement activation locus and was centered over a tyrosine-402 --> histidine-402 protein polymorphism in the gene encoding complement factor H. Possession of at least one histidine at amino acid position 402 increased the risk of AMD 2.7-fold and may account for 50% of the attributable risk of AMD.  相似文献   

Magmatic gas composition reveals the source depth of slug-driven strombolian explosive activity   总被引：2，自引：0，他引：2  

Burton M  Allard P  Muré F  La Spina A 《Science (New York, N.Y.)》2007,317(5835):227-230

Strombolian-type eruptive activity, common at many volcanoes, consists of regular explosions driven by the bursting of gas slugs that rise faster than surrounding magma. Explosion quakes associated with this activity are usually localized at shallow depth; however, where and how slugs actually form remain poorly constrained. We used spectroscopic measurements performed during both quiescent degassing and explosions on Stromboli volcano (Italy) to demonstrate that gas slugs originate from as deep as the volcano-crust interface (approximately 3 kilometers), where both structural discontinuities and differential bubble-rise speed can promote slug coalescence. The observed decoupling between deep slug genesis and shallow (approximately 250-meter) explosion quakes may be a common feature of strombolian activity, determined by the geometry of plumbing systems.  相似文献   

Human dispersal into Australasia     

Smith MA  Tacon PS  Curnoe D  Thorne A 《Science (New York, N.Y.)》2007,315(5812):597-8; author reply 597-8

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