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Three methods of analysis were used to determine the diet of territorial hooded crows at Lough Hyne Marine Reserve, Co Cork, Ireland The regular collection of prey Items from these sites at Lough Hyne was integrated with pellet and stomach analysis to determine diet Intertidal organisms occurred in over 80% of pellets and 43% of stomachs and occupied over 77% of the total wet weight of foods identified in pellets All prey items recovered from drop sites originated from the intertidal habitat, involved either large-sized species or larger individuals of smaller-sized species, and were only dropped during October to February Twenty-five intertidal species were identified but only a few of these species contributed to the bulk of the diet Hooded crows were shown to consume a wide range of intertidal species throughout the year, though the species composition in the diet was seasonally influenced Depletion and weight loss of intertidal molluscs through the winter was shown to have a minimal effect on selection suggesting that prey switching was driven by the birds nutritional requirements 相似文献
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Marianne E. Walsh Charles M. Collins Thomas F. Jenkins Alan D. Hewitt Jeff Stark Karen Myers 《Soil & Sediment Contamination》2003,12(5):631-645
Fort Greely, Alaska has an extensive complex of weapon training and testing areas located on lands withdrawn from the public domain under the Military Lands Withdrawal Act (PL106-65). The Army has pledged to implement a program to identify possible munitions contamination. Because of the large size (344,165,000 m2) of the high hazard impact areas, characterization of these constituents will be difficult. We used an authoritative sampling design to find locations most likely to contain explosives-residues on three impact areas. We focused our sampling on surface soils and collected multi-increment and discrete samples at locations of known firing events and from areas on the range that had craters, pieces of munitions, targets, or a designation as a firing point. In the two impact areas used primarily by the Army, RDX was the most frequently detected explosive. In the impact area that was also used by the Air Force, TNT was the most frequently detected explosive. Where detected, the explosives concentrations generally were low (<0.05 mg/kg) except in soils near low-order detonations, where the explosive-filler was in contact with the soil surface. These low-order detonations potentially can serve as localized sources for groundwater contamination if positioned in recharge areas. 相似文献
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Magnetic circular dichroism studies on the heme and tryptophan components of cytochrome c peroxidase 总被引:1,自引:0,他引:1
We have measured the magnetic circular dichroism of cytochrome c peroxidase and some of its derivatives from 250-350 nm. Comparison of the changes observed on conversion to the catalytic intermediate (cytochrome c peroxidase-I) with spectra obtained from horseradish peroxidase and its derivatives and model compounds of protoheme leads us to the conclusion that the observed changes in the magnetic circular dichroism spectra reflect conversion of the heme to the ferryl state. No evidence was found for modification of tryptophan in cytochrome c peroxidase-I. 相似文献
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The lipid composition of swimming spores, cysts and five hour germlings was established. Spores utilized triglycerides first, then phospholipids. Upon encystment all glycolipid components decreased, while in germlings the phospholipids, monoglycerides and sterol esters exhibited a marked increase. 相似文献
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Optimal alignments in linear space 总被引:40,自引:0,他引:40
Space, not time, is often the limiting factor when computingoptimal sequence alignments, and a number of recent papers inthe biology literature have proposed space-saving strategies.However, a 1975 computer science paper by Hirschberg presenteda method that is superior to the new proposals, both in theoryand in practice. The goal of this paper is to give Hirschberg'sidea the visibility it deserves by developing a linear-spaceversion of Gotoh's algorithm, which accommodates affine gappenalties. A portable C-software package implementing this algorithmis available on the BIONET free of charge.
Received on October 14, 1987; accepted on December 19, 1987 相似文献