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1001 - 1025 of 1229 Items << < 36 37 38 39 40 41 42 43 44 45 > >>
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The family Bibionidae has a worldwide distribution and includes
approximately 700 species in eight extant genera. Recent studies have not produced
compelling evidence supporting Bibionidae as a monophyletic group or identified the
sister group to...
2004-06-03 (iso8601)
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The structure and transcriptional activity of intranuclear
and isolated chromatin from logarithmically growing
yeast cells has been compared to chromatin from cells which
have entered the stationary phase and ceased growing. Both
chromatins show a...
1980-10-02 (iso8601)
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This study examined the abundance, size, growth, and age of advance regeneration
Douglas-fir, beneath an eighty year-old overstory at a single site on plots subjected to different overstory thinning treatments. Treatments consisted of keeping...
1998-06-03 (iso8601)
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Two North American subspecies of Snowy Plovers (Charadrius alexandrinus) have been
described: the Cuban Snowy Plover (C. a. tenuirostris) and the Western Snowy Plover
(C. a. nivosus). Coastal populations of the Western Snowy Plover are listed as...
2000-06-06 (iso8601)
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The contribution of rare taxa to bioassessments based on multispecies assemblages is the subject of continued debate. As a result, users of predictive models such as River InVertebrate Prediction and Classification System (RIVPACS) disagree on...
2007-01-01
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Sampling techniques were evaluated to quantify immature mint flea
beetle (MFB), Longitrsus waterhousei Kutschera (Coleoptera: Chrysomelidae),
on peppermint (Mentha piperita L.), in central Oregon. During the study
period, 1985-1988, soil samples...
1989-03-07 (iso8601)
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Western forests have become increasingly fragmented landscapes dominated
by young stands. Given that western Oregon forests largely consist of headwater
systems, there is a need to better understand how headwater forest taxa and their
habitats are...
2007-07-12T22:00:41Z (iso8601)
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Bear lake sculpin Cottus extensus exhibit ontogenetic habitat shifts during their initial year of life. Distribution and habitat switching was measured with bimonthly bottom-trawl surveys repeated throughout the summer. Patterns of daily growth...
1999-01-01
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The Pseudophyllidean tapeworm, Schistocephalus solidus, is a parasite that
requires both copepods and fish, mainly the threespine stickleback (Gasterosteus
aculeatus) as intermediate hosts, and birds as its final host to complete its life cycle....
2004-04-19 (iso8601)
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Understanding seasonal changes in growth, survival, and movement rates is
crucial to salmonid management. These life history characteristics provide a context for
evaluation of management actions. We evaluated the life history of individually...
2007-01-18T21:28:23Z (iso8601)
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The potential for achieving sustainable and efficient harvesting of three species of migratory tuna in the
Western and Central Pacific Ocean is examined. The stocks reside in exclusive economic zones (mainly those of Pacific island countries) and...
2008 (iso8601)
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Prior studies have demonstrated that juvenile walleye pollock Theragra chalcogramma forage socially in schools for spatially and temporally clumped food, but forage more independently for spatially and temporally dispersed food. One advantage of...
1997-07-10 (iso8601)
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Phytoplankton samples were collected in Lake Mend 6 times from September 1910 to June 1971 for 8 stations at depths of 0. 3, 5, 10, 20, and 30 m. These samples were processed through a Millipore filter apparatus and 79 planktonic algae were...
1974-01-01
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Chlorinated hydrocarbon residues (DDT metabolites, dieldrin, and PCB's) were found in fish flesh samples and sediment in American Falls Reservoir. The concentration and type of chlorinated hydrocarbon varied with fish species and age. The mean...
1976-01-01
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In many regions of the world, the extremes of winter cold are a major determinant of the geographic distribution of perennial plant species and of their successful cultivation. In the United States, the U.S. Department of Agriculture (USDA) Plant...
2012-02 (iso8601)
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We previously developed a spatially explicit, individual-based model (IBM) evaluating the bio-economic efficiency of fishing vessel movements between regions according to the catching and targeting of different species based on the most recent...
2012 (iso8601)
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Soil that is contaminated with radioactive elements poses an exposure hazard
to those whom may take up temporary or permanent residence on such a site. Of
particular interest is the internal exposure from ingestion of this radioactive soil....
2006-03-01 (iso8601)
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1982 - 2002; ill., maps; Title covers calendar years 1990-2002; Bibliographic description is based on 1990 annual report; CA 9000-8-0006 Subagreement 8; Includes bibliographic references
2009-01-22 2009-04-02 |
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From April 1993 to September 1995, the U.S. Geological Survey conducted a study of the occurrence and distribution of nutrients and pesticides in surface water of the Willamette and Sandy River Basins, Oregon, as part of the U.S. Geological Survey...
1998-11-10
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Numerous isolates of Armillaria mellea were obtained within
a 250 by 450 foot Study Area in a ponderosa pine plantation in central
Oregon. These isolates were recovered from roots of armillaria-killed
young-growth pine, from large stumps of the...
1972-04-28 (iso8601)
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