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Full-Text Articles in Life Sciences

Vegetation Development In Relation To Age Of River Stabilization Structures Along A Channelized Segment Of The Missouri River, John Arthur Vaubel Jun 1975

Vegetation Development In Relation To Age Of River Stabilization Structures Along A Channelized Segment Of The Missouri River, John Arthur Vaubel

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

During the summer of 1974, I sampled sites of vegetation representative of successional trends in plant communities along the Missouri River floodplain from Sioux City, Iowa, to Rulo, Nebraska. Five district community types listed from youngest to oldest are as follows: Salix spp. – dominated, Populus deltoides – dominated, Platanus occidentalis-Ulmus rubra – dominated, Tilia americana-Quercus rubra – dominated, and Quercus macrocarpa-Carya ovata – dominated vegetation.

The technique of relating vegetation succession to age of river stabilization structures was found to be useful and offered a quite precise method of developing a timescale …


Shell Growth In The Scallop Argopecten Irradians. I. Isotope Incorporation With Reference To Diurnal Growth, Alfred P. Wheeler, Patricia Blackwelder, Karl M. Wilbur Jun 1975

Shell Growth In The Scallop Argopecten Irradians. I. Isotope Incorporation With Reference To Diurnal Growth, Alfred P. Wheeler, Patricia Blackwelder, Karl M. Wilbur

Marine & Environmental Sciences Faculty Articles

1. Incorporation of calcium and carbonate into shell has been studied in the scallop Argopecten irradians using 45Ca and 14C-bicarbonate.

2. The incorporation of 45Ca and 14C-carbonate into shell was linear with time after a lag period of 1 to 2 hours. The shell-forming mantle tissue attained a steady state with respect to 45Ca in the sea water medium within 2 hours.

3. The molar ratio of 45Ca to 14C-carbonate deposited in shell was not significantly different from unity during 5 hours.

4. The rate of incorporation of 14C-carbonate into shell was …


Performance Appraisal In Hospital Dietary Departments, Mary C. Law Jun 1975

Performance Appraisal In Hospital Dietary Departments, Mary C. Law

Loma Linda University Electronic Theses, Dissertations & Projects

The specific objectives of this research were to (1) identify the principal characteristics and functions of performance appraisal programs utilized in hospital dietary departments, (2) determine the ten major factors in performance appraisal as indicated by the hospital dietary department directors as well as by dietetic interns and the factors indicated in the review of literature, and (3) develop an evaluation form for performance appraisal of hospital dietary department employees utilizing criteria obtained from (1) and (2).

Three hundred general, short term, nonprofit hospitals were included into the study. Questionnaires were mailed to three hospitals which were classified according to …


An Evaluation Of The Fishery Resources Of The Thames River Watershed, Connecticut, Connecticut Department Of Environmental Protection May 1975

An Evaluation Of The Fishery Resources Of The Thames River Watershed, Connecticut, Connecticut Department Of Environmental Protection

Storrs Agricultural Experiment Station

No abstract provided.


Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray May 1975

Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two intermediate wheatgrass seedings with different levels of grass bug infestation were evaluated for herbage production, seedhead production, percent dry matter, crude protein, and cell contents. Study sites were located at different elevations on mountain summer ranges in northern (Site I) and central (Site II) Utah. Study plots at Site I and Site II were infested with 113 and 210 bugs per sweep, respectively. Herbage production appeared to be reduced in early spring on the site with the higher infestation; however, no effect on season-long herbage production could be detected on either site. Seedhead production on infested plots was reduced …


Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki May 1975

Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki

Publications (WR)

The 14C light and dark bottle technique for measurement of primary production was utilized as a means of assessing the amount of inorganic carbon being converted Into organic form by the photosynthesis of phytoplankton populations In the Boulder Basin of Lake Mead.

Spatial and time series changes of productivity levels observed at eight sampling locations within Boulder Basin Indicate that the Influence of treated municipal arts' industrial effluent flowing into Les Vegas Bay is contributing high levels of available nutrients at Las Vegas Wash Inlet to cause productivity to approximate those levels associated with polluted waters.

Productivity levels at …


State Of The Fisheries Report 1974, Department Of Fisheries And Wildlife, Western Australia May 1975

State Of The Fisheries Report 1974, Department Of Fisheries And Wildlife, Western Australia

Status Reports of the Fisheries and Aquatic Resources

The total value of the fisheries of Western Australia is the highest of any of the States, and the Western Australian rock lobster fishery is the most valuable single fishery in Australia.


Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal May 1975

Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The upper optimum temperature for embryonic development of mountain whitefish is 6 C, and for the post yolk sac stage is 9 to 12 C. The need to know effects on all stages in the life cycle in cases of thermal pollution is demonstrated. Abnormalities caused by thermal pollution in hatched larvae were agape jaws, coloboma or fissure of the eye, monophthalmia or the presence of only one eye, monomicrophthalmia or the presence of one small eye and one case of twinning. High mortalities of eggs occurred at 9 C and higher.

Study of the energy expenditure, by the dry …


Factors Influencing Germination And Seedling Survival Of Several Varieties Of Astragalus Lentiginosus Dougl., Paul Ziemkiewicz May 1975

Factors Influencing Germination And Seedling Survival Of Several Varieties Of Astragalus Lentiginosus Dougl., Paul Ziemkiewicz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Astragalus lentiginosus, which consists of 36 varieties, is one of the principal locoweeds of western North America. The objectives of this study included identification of some of the major factors affecting germination of the seed and survival of the newly established seedlings for several of these varieties.

The seeds of the varieties studied exhibited two mechanisms for dormancy. One is a seed coat that is impermeable to water, and the other is a water-leachable inhibitor. The presence or absence of low-intensity incandescent light (in 14-hour day lengths) had no effect on germination. Of three temperature regimes studied, the regime …


Exploratory Sensitivity Analysis Of A Stream Ecosystem Model, Joseph H. Wlosinski May 1975

Exploratory Sensitivity Analysis Of A Stream Ecosystem Model, Joseph H. Wlosinski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The framework of a stream ecosystem simulation model is described. Using this framework and data from two different geographical areas, a cold desert stream and a generalized mountain stream, exploratory sensitivity analysis was performed on the model. This was accomplished by qualitatively comparing outputs of a series of simulations in which a different level of a driving variable was used in each simulation. Based on these results, recommendations are made for improving the structure of the model.


Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson May 1975

Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although water stress is an important selective force in many environments, it is not commonly considered to be of particular importance in tundra areas. Even though large portions of tundra may have an abundance of water, other more exposed areas may become quite dry. This microsite variability with respect to moisture stress was reflected in soil water potential measurements obtained from an alpine tundra area on Niwot Ridge in Colorado. Even though soil water potentials were consistently above -5 bars in a relatively low lying Deschampsia meadow, soil water potentials from an exposed fellfield area were often as low as …


Abstracts Of Papers Scheduled For Presentation At The 87th Session Of The Iowa Academy Of Science, April 19, 1975, Iowa Academy Of Science Apr 1975

Abstracts Of Papers Scheduled For Presentation At The 87th Session Of The Iowa Academy Of Science, April 19, 1975, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


The 87th Session Of The Iowa Academy Of Science, April 17-19, 1975, Iowa Academy Of Science Apr 1975

The 87th Session Of The Iowa Academy Of Science, April 17-19, 1975, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Close Coupling Test Of Classical And Semiclassical Cross Sections For Rotationally Inelastic Ar-N2 Collisions, Russell T. Pack Apr 1975

Close Coupling Test Of Classical And Semiclassical Cross Sections For Rotationally Inelastic Ar-N2 Collisions, Russell T. Pack

Faculty Publications

Accurate quantum mechanical close coupling (CC) integral cross sections are reported for rotationally inelastic Ar-N2 collisions at room temperature using an empirical intermolecular potential. These cross sections are used to test the infinite order sudden (IOS) approximation and the results of several methods [classical trajectories (CT), full sudden (SA), generalized phase shift (GPS), and classical limit generalized phase shift (CGPS)] as reported in the preceding paper by Pattengill. The IOS approximation works very well for cross sections involving low rotational states. The CT method works well for all the cross sections examined, justifying the popular belief that the rotational motion …


Use Of Selected Macroinvertebrates As Indicators Of Sedimentation Effects On Huntington River, Utah, Michael Kenneth Reichert Mar 1975

Use Of Selected Macroinvertebrates As Indicators Of Sedimentation Effects On Huntington River, Utah, Michael Kenneth Reichert

Theses and Dissertations

Benthic macroinvertebrate communities of Huntington River, Emery County, Utah were studied to determine effects of sedimentation from construction of Electric Lake Dam, a state highway, and two bridges. Approximately 900 benthic samples were collected from riffle areas above, in, and below the construction zone from January, 1971 to December, 1973. Two settling basins below construction sites were effective in limiting scouring of downstream communities. Heavy silt deposition was limited to a 1-km stream reach. Number of indicators, density, and biomass were reduced in the construction zone during periods of sediment input. During periods of scouring, density and biomass were reduced; …


The Prairie Naturalist Volume 7, No.1. March 1975 Mar 1975

The Prairie Naturalist Volume 7, No.1. March 1975

The Prairie Naturalist

MIGRATION OF BIRDS IN NORTH DAKOTA DURING FAll 1974 ▪ J. T. Lokemoen & D. H. Johnson.

REPRODUCTION AND DEVELOPMENT OF FOUR MALLARD LINES ▪ R. J. Greenwood


1974 Seed Yield Of Early Maturing Crossbreds Under Wheatbelt Conditions, C. M. Francis Feb 1975

1974 Seed Yield Of Early Maturing Crossbreds Under Wheatbelt Conditions, C. M. Francis

Experimental Summaries - Plant Research

Small plot trials sited at Merredin, Bencubbin and Bungil again demonstrated the 'bred' varieties to be at least the equal of Geraldton or Northam A under wheatbelt conditions. Growing season conditions at Bencubbin were the best for pasture in recent years. Merredin and Bungil also received above average rainfall but encountered dry conditions in September. Predictably the coarse siliceous nature of the Wodgil soil at Bungil in conjunction with the dry period produced very low seed yields. Crossbred 175.1.3 the leading crossbred at Merredin in 1973, was again significantly better than Geraldton or Northam A at Merredin and Bungil (Table …


Scimitar-Toothed Cats, Machairodus And Nimravides, From The Pliocene Of Kansas And Nebraska, Larry D. Martin, C. Bertrand Schultz Feb 1975

Scimitar-Toothed Cats, Machairodus And Nimravides, From The Pliocene Of Kansas And Nebraska, Larry D. Martin, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum (1924–2023)

"Machairodus catocopis Cope" is shown to be a pseudaelurin cat belonging to the genus Nimravides Kitts. Nimravides thinobates (Macdonald) is a possible synonym of N. catocopis (Cope). Nimravides is compared with the Eurasian Machairodus-like cat, Dinofelis. Machairodus (Heterofelis) coloradensis is reported from the Kimball Formation, upper Pliocene (Kimballian) of Cheyenne County, Nebraska, and from the upper part of the Ash Hollow Formation, Pliocene (Hemphillian) of Sherman County, Nebraska. The Kimballian form is described as a new subspecies, Machairodus coloradensis tanneri.

The genus Machairodus has long been associated with the Hemphillian of North America and the …


Summary Of 1974 Dock Control Field Trials, J M. Allen Feb 1975

Summary Of 1974 Dock Control Field Trials, J M. Allen

Experimental Summaries - Plant Research

Dock control - Spray graze evaluations - 73BY8, 73HA4, 73BU5, 73MA6, 73DE6 Dicamba in pastures - 73AL38, 73BU9, 73AR9


Summary Of Trial Results - 1974, N R. Mckeown Feb 1975

Summary Of Trial Results - 1974, N R. Mckeown

Experimental Summaries - Plant Research

Observations and measurements were made on 10 grazing trials and 11 small-plot legume species trials in 1974. Three of the grazing trials were under crop, two of them concluding low oestrogen species trials which had been grazed since 1969, and one of them, 68M023, West Moora, as an interval between pasture phases. The small-plot trials dated from 1970 or later and on most of them half of each plot could be grazed by sheep and half was protected. These trials have continued to supply useful information on the suitabiliy of cultivars to soil and climate and will be the subject …


A New Kimballian Peccary From Nebraska, C. Bertrand Schultz, Larry D. Martin Feb 1975

A New Kimballian Peccary From Nebraska, C. Bertrand Schultz, Larry D. Martin

Bulletin of the University of Nebraska State Museum (1924–2023)

A new species of Pliocene peccary, Prosthennops (Macrogens) graffhami; is described from the Kimball Formation, Ogallala Group, Frontier County, Nebraska. This new species is the latest in geologic age and most advanced in the genus.

The remains of fossil vertebrates are generally rare in the upper part of the Ogallala group, and some have maintained that Hemphillian faunas such as Coffee Ranch and Smith County, Kansas, represent the latest Ogallala faunas. Later faunas than are typically considered as Hemphillian, containing more advanced forms, occur in the Kimball Formation and deposits of equivalent age. Known faunas which may …


Bears (Ursidae) From The Late Cenozoic Of Nebraska, C. Bertrand Schultz, Larry D. Martin Feb 1975

Bears (Ursidae) From The Late Cenozoic Of Nebraska, C. Bertrand Schultz, Larry D. Martin

Bulletin of the University of Nebraska State Museum (1924–2023)

A ramus and partial premaxilla establish the presence of a new subspecies of Indarctos in the upper Pliocene (Kimball Formation, Ogallala Group) of Frontier County, Nebraska. An extremely large species of Agriotherium is represented by fragmentary remains from the middle Pliocene (middle part of Ash Hollow Formation, Ogallala Group) of Sherman County, Nebraska.

This study is part of a series of papers dealing primarily with the fauna of the Kimball formation in Nebraska (Barbour 1927, 1929; Barbour and Schultz, 1941; Schultz and Stout, 1948, 1961; Kent 1963, 1967; Tanner, 1967; Short, 1969; Martin and Tate, 1970; Schultz, Schultz, and Martin, …


Cenozoic Mammals From The Central Great Plains, C. Bertrand Schultz, Larry D. Martin, R. George Corner, Lloyd G. Tanner Feb 1975

Cenozoic Mammals From The Central Great Plains, C. Bertrand Schultz, Larry D. Martin, R. George Corner, Lloyd G. Tanner

Bulletin of the University of Nebraska State Museum (1924–2023)

Includes:

Part 1. Middle and Late Cenozoic Tapirs from Nebraska. By C. Bertrand Schultz, Larry D. Martin, and R. George Corner.

Part 2. Stratigraphic Occurrences of Teleoceras, with a New Kimballian Species from Nebraska. By Lloyd G. Tanner.

Part 3. A New Kimballian Peccary from Nebraska. By C. Bertrand Schultz and Larry D. Martin.

Part 4. Bears (Ursidae) from the Late Cenozoic of Nebraska. By C. Bertrand Schultz and Larry D. Martin.

Part 5. Scimitar-toothed Cats, Machairodus and Nimravides, from the Pliocene of Kansas and Nebraska. By Larry D. Martin and C. Bertrand Schultz.

84 pp


Electrochemical Machining (Ecm) With Alternating Current, S. J. Shine Jan 1975

Electrochemical Machining (Ecm) With Alternating Current, S. J. Shine

Tanzania Journal of Science

Electrochemistry has had several practical uses in industry for a long time; but one of the more recent applications is the machining of metals. Direct current ECM has been applied in industry for the last two decades. However, ECM with alternating current is still in the early stage of research and development. This paper shows that ECM with normal a.c supply is feasible and practicable if special tools are used. ECM with d.c. is first introduced to provide a better insight for the machining with a.c.


An Iteration Formula For Finding Roots Of Equations, R. W. P. Masenge Jan 1975

An Iteration Formula For Finding Roots Of Equations, R. W. P. Masenge

Tanzania Journal of Science

We seek the roots of the equation f(x) = 0.


The Kunduchi Mangrove Basin, Alison Mccusker Jan 1975

The Kunduchi Mangrove Basin, Alison Mccusker

Tanzania Journal of Science

The pattern of tidal submergence and exposure in the Kunduchi mangrove basin is determined by contour mapping and by relating the contours to published tide predictions. Salinity of the creek effluent is measured at spring and neap tides in both wet and dry seasons. The vegetation of the basin, up to the highest high water level, is described briefly.


Distribution And Relative Abundance Of Billfishes (Istiophoridae) Of The Indian Ocean, John Kenneth Howard, Walter A. Starck Ii Jan 1975

Distribution And Relative Abundance Of Billfishes (Istiophoridae) Of The Indian Ocean, John Kenneth Howard, Walter A. Starck Ii

Studies in Tropical Oceanography

No abstract provided.


Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, P. L. Comanor Jan 1975

Decomposition And Mineralization In An Artemisia Tridentata Community In Northern Nevada, P. L. Comanor

Memorandum

No abstract provided.


Water Loss In Chihuahuan Desert Ants, W. G. Whitford, C. A. Kay, A. M. Schumacher Jan 1975

Water Loss In Chihuahuan Desert Ants, W. G. Whitford, C. A. Kay, A. M. Schumacher

Memorandum

No abstract provided.


Biology Of Nematodes In Desert Ecosystems, D. W. Freckman, R. Mankau, S. A. Sher Jan 1975

Biology Of Nematodes In Desert Ecosystems, D. W. Freckman, R. Mankau, S. A. Sher

Memorandum

No abstract provided.