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Page 5778, results 144426 - 144450

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Experimental hybridization among five species of lampreys from the Great Lakes
George W. Piavis, John H. Howell, Allen J. Smith
1970, Copeia (1970) 29-37
Experimental hybridization among five species of lampreys of the Upper Great Lakes routinely produced embryos through stage 8, and four crosses produced embryos to the larval stage. Three critical periods in the embryogenesis of hybrid lampreys were between stages 8 and 9, among stages 10, 11, and 12, and at...
Fin degeneration of young-of-the-year Alosa pseudoharengus (Clupeidae) in southern Lake Michigan
Edward H. Brown Jr., Carroll R. Norden
1970, Copeia (1970) 766-769
Young-of-the-year alewives, Alosa pseudoharengus, with extremely shortened caudal fins were observed at four locations in southern Lake Michigan between 1964 and 1968. Some of the fins appeared stunted or underdeveloped, but microscopic examination revealed a deterioration of the fins and not an ontogenetic abnormality. Deterioration of the caudal fin was...
Concentrations of trace elements in Great Lakes fishes
Henry F. Lucas Jr., David N. Edgington, Peter J. Colby
1970, Journal of the Fisheries Research Board of Canada (27) 677-684
The concentration of 15 trace elements was determined by activation analysis of samples of whole fish and fish livers from three of the Great Lakes: Michigan, Superior, and Erie. The average concentrations of 7 elements in 19 whole fish from 3 species were as follows: uranium, 3ppb (parts per billion);...
Body-scale relation and calculation of growth in fishes
Ralph Hile
1970, Transactions of the American Fisheries Society (99) 468-474
Most calculations of fish growth from scale measurements are made from one of four types of curves: straight line through the origin (Dahl-Lea); straight line with intercept (Lee); logarithmic line (Monastyrsky); empirically derived curve (SegerstråYle). Occasionally, different curves are used for different length intervals of fish. Present understanding of the...
Resource crises in Lake Erie
Wilbur L. Hartman
1970, Explorer (12) 6-11
Despite the tremendous value of the Great Lakes, a malaise is seriously destroying their worth. Accelerated enrichment, unabated pollution, over-exploitation, and accidental and intentional introduction of exotic species, have all been guided--more often misguided--by man. Of all five Great Lakes, Lake Erie stands out as the one most...
Aerial infrared surveys of Reykjanes and Torfajökull thermal areas, Iceland, with a section on cost of exploration surveys
G. Pálmason, J. D. Friedman, R. S. Williams Jr., J. Jonsson, K. Saemundsson
1970, Geothermics (2) 399-412
In 1966 and 1968 aerial infrared surveys were conducted over 10 of 13 high-temperature thermal areas in Iceland. The surveys were made with an airborne scanner system, utilizing radiation in the 4.5–5.5 μm wavelength band.Supplementary ground geological studies were made in the Reykjanes and Torfajökull thermal areas to interpret features...
Temperature tolerance of bloater (Coregonus hoyi)
Thomas A. Edsall, Donald V. Rottiers, Edward H. Brown
1970, Journal of the Fisheries Research Board of Canada (27) 2047-2052
Juvenile and young adult bloaters (Coregonus hoyi) were tested for tolerance to high temperatures. The ultimate upper lethal temperature of juvenile bloaters (26.75 C) appeared to be slightly higher than that of young adult bloaters, but was similar to that of juvenile ciscoes,Coregonus artedii (26.0 C), the only other North American coregonine for...
Photogeologic and thermal infrared reconnaissance surveys of the Los Negritos-Ixtlan de los Hervores geothermal area, Michoacan, Mexico
Valle R. Gomez, J. D. Friedman, S.J. Gawarecki, C.J. Banwell
1970, Geothermics (2)
New techniques, involving interpretation of panchromatic, ektachrome and ektachrome infrared aerographic photogaphs and thermographic infrared imagery recording emission from the earth's surface in middle and far infrared wavelengths (3–5μm and 8–14μm), are being introduced in geothermal investigations in Mexico to identify outstanding structural and geologic features in a rapid and...
Atmospheric collection of debris from the Revelstoke and Allende fireballs
M. H. Carr
1970, Geochimica et Cosmochimica Acta (34) 689-700
In two separate events, Revelstoke and Allende, the air through which a fireball had been observed to pass was sampled for meteoritic debris. Particulate matter was collected on fibrous filters, which were mounted on aircraft and flown downwind from the site of the...
Effect of sample inhomogeneity in K Ar dating
J. C. Engels, C.O. Ingamells
1970, Geochimica et Cosmochimica Acta (34) 1007-1017
Error in K-Ar ages is often due more to deficiencies in the splitting process, whereby portions of the sample are taken for potassium and for argon determination, than to imprecision in the analytical methods. The effect of the grain size of a sample and of the composition of a contaminating...
UThPb age of Apollo 12 rock 12013
M. Tatsumoto
1970, Earth and Planetary Science Letters (9) 193-200
A UThPb isotopic study of three chips from lunar rock 12013 indicates that parental material of the intrusion breccia formed quite early in the moon's history, possibly 3.9 to 4.3 by ago. The UThPb characteristics of the rock are distinctly different from those of other Apollo 12 igneous rocks and...
Waterfowl breeding habitat in agricultural and nonagricultural land in Manitoba
T.J. Dwyer
1970, Journal of Wildlife Management (34) 130-136
Waterfowl populations and habitat characteristics were examined on 33 potholes in each of two 16-square-mile study areas of agricultural and nonagricultural land in southwestern Manitoba. The agricultural land potholes, lacking in or incompletely surrounded by trees, received greater use by lesser scaup (Aythya affinis), canvasback (A. valisineria), redhead (A. americana),...
Analytical sensitivities and energies of thermal-neutron-capture gamma rays
D. Duffey, A. El-Kady, F. E. Senftle
1970, Nuclear Instruments and Methods (80) 149-171
A table of the analytical sensitivities of the principal lines in the thermal-neutron-capture gamma ray spectrum has been compiled for most of the elements. In addition a second table of the full-energy, single-escape, and double-escape peaks has been compiled according to energy for...
Isotopic composition of strontium in sea water throughout Phanerozoic time
Z. E. Peterman, C. E. Hedge, H. A. Tourtelot
1970, Geochimica et Cosmochimica Acta (34) 105-120
Isotopic analyses of strontium in primary fossil carbonate reveal significant variations in Sr87Sr86">Sr87Sr86 of sea water during the Phanerozoic. The strontium isotopic composition may have been uniform from the Ordovician through the Mississippian, with an average Sr87Sr86">Sr87Sr86 of 0.7078. A subsequent decrease...
Neutron radiative capture methods for surface elemental analysis
J.I. Trombka, F. Senftle, R. Schmadebeck
1970, Nuclear Instruments and Methods (87) 37-43
Both an accelerator and a 252Cf neutron source have been used to induce characteristic gamma radiation from extended soil samples. To demonstrate the method, measurements of the neutron-induced radiative capture and activation gamma rays have been made with both Ge(Li) and NaI(Tl) detectors, Because...