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Full-Text Articles in Physical Sciences and Mathematics

Growth And Reproduction Of Eupleura Caudata (Say) In The York River, Virginia, Clyde L. Mackenzie Jan 1958

Growth And Reproduction Of Eupleura Caudata (Say) In The York River, Virginia, Clyde L. Mackenzie

Dissertations, Theses, and Masters Projects

No abstract provided.


A Comparative Study Of Meristic Variation In The American Eel (Anguilla Rostrata) And Atlantic Anchovy (Anchoa Mitchilli), Ernest C. Ladd Jan 1958

A Comparative Study Of Meristic Variation In The American Eel (Anguilla Rostrata) And Atlantic Anchovy (Anchoa Mitchilli), Ernest C. Ladd

Dissertations, Theses, and Masters Projects

No abstract provided.


Chemosynthetic Microorganisms In Leaching Sulfide Minerals, A. Keith Jameson Jul 1957

Chemosynthetic Microorganisms In Leaching Sulfide Minerals, A. Keith Jameson

Theses and Dissertations

This investigation showed that a single bacterium was capable of sulfide oxidation in exposed ore bodies. This single bacterium was isolated and characterized. It exhibited different characteristics than any previously known organism. It was found to be a chemosynthetic autotroph. An optimum nutrient concentration was determined for pyrite oxidation. The nutrient concentration was determined for pyrite oxidation. The nutrient contains only a source of phosphate and nitrogen. Urea was found to be a better source of nitrogen than ammonium sulfate which had previously been used. The effect of various organic compounds on the oxidation of pyrite was observed. Glucose and …


The Use Of Branchiostegal Rays To Determine Age Of Lake Trout Salvelinus Namaycush Walbaum, Ross Vivian Bulkley May 1957

The Use Of Branchiostegal Rays To Determine Age Of Lake Trout Salvelinus Namaycush Walbaum, Ross Vivian Bulkley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Any method used in aging fish must fulfill certain requirements to be satisfactory. If the method is inaccurate, naturally little reliance can be placed upon its use. If considerable study of the method and much practice are required before accurate readings can be obtained, the method will not come into widespread use. The requirements of an aging method, then are that it must be accurate and comparatively easy. The scale method for aging lake trout (Salvelinus namaycush Walbaum) unfortunately does not fulfill these requirements. It has always been difficult to tell the age of lake trout by the examination …


Medial Pleistocene Fossil Vertebrate Localities In Nebraska, C. Bertrand Schultz, Lloyd G. Tanner Jan 1957

Medial Pleistocene Fossil Vertebrate Localities In Nebraska, C. Bertrand Schultz, Lloyd G. Tanner

Bulletin of the University of Nebraska State Museum

The accurate geologic dating of Pleistocene vertebrate localities which occur outside the glaciated regions has always been difficult. Several new fossil localities in Nebraska now provide data for a better understanding of the paleoecology and faunal evidence of the medial Pleistocene of the Great Plains region.

A fossil quarry, containing the remains of both vertebrates and invertebrates, has been discovered in south-central Nebraska (11/2 miles south and west of Angus in Nuckolls County). The fossils are preserved in Sappa silts in a lime concentration zone (C horizon) of a Yarmouth paleosol. The calcium carbonate appears to have been responsible for …


Effect Of Environment On The Percentage Of Summerwood And Specific Gravity Of Slash Pine, Philip R. Larson Jan 1957

Effect Of Environment On The Percentage Of Summerwood And Specific Gravity Of Slash Pine, Philip R. Larson

Yale School of the Environment Bulletin Series

No abstract provided.


Nebraska Deer, William Bailey Jr., George Schildman, Phillip Agee, C. G. Pritchard Jan 1957

Nebraska Deer, William Bailey Jr., George Schildman, Phillip Agee, C. G. Pritchard

Nebraska Game and Parks Commission: Publications

IN COMMON with the experience of most states, Nebraska's deer herds were reduced to a very low level by excessive harvests in our early history. Most American big-game animals were overharvested in the early history of this nation because of commercialization. Buffalo were killed for their hides, deer for their meat. This slaughter continued as long as the hunter (or poacher) could sell his take at a profit. Modem game management and public opinion reversed this trend. Deer are on the way back all over America, and in some states the protection-complex was so strong that deer were restored to …


The Length And Age Composition Of Spot, Leiostomus Xanthurus, In The Pound Net Fishery Of Lower Chesapeake Bay, Anthony Louis Pacheco Jan 1957

The Length And Age Composition Of Spot, Leiostomus Xanthurus, In The Pound Net Fishery Of Lower Chesapeake Bay, Anthony Louis Pacheco

Dissertations, Theses, and Masters Projects

No abstract provided.


Nebraska Deer, William Bailey Jr., George Schildman, Phillip Agee, C. G. Pritchard Jan 1957

Nebraska Deer, William Bailey Jr., George Schildman, Phillip Agee, C. G. Pritchard

Nebraska Game and Parks Commission: Publications

IN COMMON with the experience of most states, Nebraska's deer herds were reduced to a very low level by excessive harvests in our early history. Most American big-game animals were overharvested in the early history of this nation because of commercialization. Buffalo were killed for their hides, deer for their meat. This slaughter continued as long as the hunter (or poacher) could sell his take at a profit. Modem game management and public opinion reversed this trend. Deer are on the way back all over America, and in some states the protection-complex was so strong that deer were restored to …


Influence Of Various Factors On Aggregation Of Peorian Loess By Microorganisms, T. M. Mccalla, Francis A. Haskins, E. F. Frolik Jan 1957

Influence Of Various Factors On Aggregation Of Peorian Loess By Microorganisms, T. M. Mccalla, Francis A. Haskins, E. F. Frolik

Department of Agronomy and Horticulture: Faculty Publications

Soil structure is important in the attainment of adequate aeration for the aerobic microorganisms whose activities maintain such higher plant nutrients as sulfur, phosphorus, and nitrogen in a highly oxidized and thus readily available state. Good soil structure is also necessary for soil and water conservation, Under Nebraska conditions microorganisms and their decomposition products constitute a major source of soil-aggregating agents. The decomposition of crop residues and plant roots is important in the nutrition of these aggregating microorganisms. Other microorganisms, however, also utilize crop residues and plant roots, and they may decompose the aggregating agents as well, so that the …


Investigations Of The Effects On Oyster Culture Of The Dredging For The Hampton Roads Bridge-Tunnel : An Investigation Conducted By The Virginia Fisheries Laboratory For The Virginia State Department Of Highways, Jay D. Able, Dexter S. Haven, John L. Mchugh Jan 1957

Investigations Of The Effects On Oyster Culture Of The Dredging For The Hampton Roads Bridge-Tunnel : An Investigation Conducted By The Virginia Fisheries Laboratory For The Virginia State Department Of Highways, Jay D. Able, Dexter S. Haven, John L. Mchugh

Reports

No abstract provided.


Ecological And Epidemiological Studies Of Nematopsis Ostrearum, A Sporozoan Parasite Of The Oyster Crassostrea Virginica, In Lower Chesapeake Bay And Its Tributaries, Sung Yen Feng Jan 1957

Ecological And Epidemiological Studies Of Nematopsis Ostrearum, A Sporozoan Parasite Of The Oyster Crassostrea Virginica, In Lower Chesapeake Bay And Its Tributaries, Sung Yen Feng

Dissertations, Theses, and Masters Projects

No abstract provided.


Range Liverstock Nutrition And Its Importance In The Intermountain Region, C. Wayne Cook Dec 1956

Range Liverstock Nutrition And Its Importance In The Intermountain Region, C. Wayne Cook

Faculty Honor Lectures

It has been estimated that about 728 million acres or about 76 percent of the entire land area in the West is used for grazing (Stoddard and Smith 1956). In Utah about 93 percent of the land area or 48,900,000 acres is considered range land (Reuss and Blanch 1951). Although some of this range land is forested, a large area of it can be used only for grazing. Therefore, range livestock production is an important segment of western agriculture.

Before 19'00 most of the animals in the West grazed on the range all year. However, irrigation crop production has expanded …


Granular Fertiliser, C R. Hale Aug 1956

Granular Fertiliser, C R. Hale

Experimental Summaries - Plant Research

There is general agreement that granulation of fertilisers improves their physical characteristics with respect to handling, storage and distribution in the field. These physical advantages rather tan any established agronomic reason appear to be responsible for the increasing use of granular fertiliser.


Oxidation Of Molybdenite With The Aid Of Microorganisms, Ralph Anderson Aug 1956

Oxidation Of Molybdenite With The Aid Of Microorganisms, Ralph Anderson

Theses and Dissertations

This work represents a study on the biological oxidation of molybdenite, MoS2. The principal objective of this study was to investigate the possibility of the biological oxidation of molybdenite, to determine the physical and chemical conditions under which the oxidative process occurs, and to develop a strain of bacteria or alter the activity of the microorganisms by acclimatization to increase their activity on sulfide minerals, in particular molybdenite. Minerals used in this study were pyrite (FeS2), chalcopyrite (CuFeS2), molybdenite concentrate, and molybdenite ore. The microorganisms used in this investigation were autotrophic bacteria obtained from the leaching streams of Bingham Canyon, …


Photo-Oxidations Sensitized By Physiologically Important Substances, Ernel D. Ihnen Jun 1956

Photo-Oxidations Sensitized By Physiologically Important Substances, Ernel D. Ihnen

Theses and Dissertations

A study of the photo-oxidation of the 2,6-dichlorophenol indophenol-ascorbic couple was undertaken with a view to investigating the postulated mechanism of oxidation by a component of the oxygen evolving sequence operative in photosynthesis. A spectrophotometric method for the measurement of the progress of photo-oxidation was developed. Temperature and pH dependence were determined and the effect of various common inhibitors and physiological substances tested. None of the common Hill reaction inhibitors were effective in the ascorbic acid photo-oxidation in the system used. KCN and catalase as well as a few other high molecular weight proteins were able to inhibit dark auto-oxidation …


The Sixty-Eighth Session Of The Iowa Academy Of Science And The Twenty-Third Convention Of The Iowa Junior Academy Of Science, April 20-21, 1956, Iowa Academy Of Science Apr 1956

The Sixty-Eighth Session Of The Iowa Academy Of Science And The Twenty-Third Convention Of The Iowa Junior Academy Of Science, April 20-21, 1956, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Arretotherium Fricki, A New Miocene Anthracothere From Nebraska, J. R. Macdonald, C. Bertrand Schultz Jan 1956

Arretotherium Fricki, A New Miocene Anthracothere From Nebraska, J. R. Macdonald, C. Bertrand Schultz

Bulletin of the University of Nebraska State Museum

A new species of middle Miocene (early Hemingfordian) anthraco-there, Arretotherium fricki Macdonald and Schultz is described based on a cranium from the upper Marsland deposits of Nebraska. The holotype suggests that this genus was derived from the Oligocene genus Elomeryx Marsh.


Tannin Content Of English Walnuts : Thesis ..., Joseph G. Natoli Jan 1956

Tannin Content Of English Walnuts : Thesis ..., Joseph G. Natoli

University of the Pacific Theses and Dissertations

Present methods for the production of leather from animal hides still depend from the most part on the use of natural tannin extracts. During the year, 1952, the amount of natural tannin extracts used by the leather industry was 560,452,119 pounds as compared to 35,793,000 pounds of synthetic tanning materials. It is not as yet possible to produce synthetic materials as economically as the natural extracts; the result being that there is still a very great demand for natural tannin extracts. The need for finding new domestic sources of tannins is apparent when the amounts of domestic and imported extracts …


Classification Of Oligocene Sediments In Nebraska: A Guide For The Stratigraphic Collecting Of Fossil Mammals, C. Bertrand Schultz, Thompson M. Stout Jun 1955

Classification Of Oligocene Sediments In Nebraska: A Guide For The Stratigraphic Collecting Of Fossil Mammals, C. Bertrand Schultz, Thompson M. Stout

Bulletin of the University of Nebraska State Museum

The Chadron and Brule formations constitute the White River Group in Nebraska and adjacent states. The Brule is divided into the Orella and Whitney members. The latter members are referred to the Medial and Late Oligocene (equivalents of the European Stampian and Aquitanian), while-the Chadron is equated with the Early Oligocene (Sannoisian). Each unit in Nebraska is subdivided into three parts (Lower, Middle, and Upper; or A, B, and C for the Chadron and Whitney, and A-B, C, and D for the Orella). Key beds such as fossil soils (paleosols), Purplish White beds, and volcanic ash layers, when considered with …


The Sixty-Seventh Session Of The Iowa Academy Of Science And The Twenty-Second Convention Of The Iowa Junior Academy Of Science, April 15-16, 1955, Iowa Academy Of Science Apr 1955

The Sixty-Seventh Session Of The Iowa Academy Of Science And The Twenty-Second Convention Of The Iowa Junior Academy Of Science, April 15-16, 1955, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Paleosols Of The Oligocene Of Nebraska, C. Bertrand Schultz, Lloyd G. Tanner, Cyril Harvey Mar 1955

Paleosols Of The Oligocene Of Nebraska, C. Bertrand Schultz, Lloyd G. Tanner, Cyril Harvey

Bulletin of the University of Nebraska State Museum

Prominent paleosol ("buried" or "fossil" soil) complexes occur at the top of the middle Orella, upper Orella, lower Whitney, and upper Whitney in the Brule formation of Nebraska; and at the top of the "Lower Oreodon," "Middle Oreodon," "Upper Oreodon," and "Leptauchenia" beds in the Brule deposits of South Dakota. These paleosols have regional distribution and appear to be of value in stratigraphic correlations. Major faunal breaks seem to coincide with important buried soil zones, thus indicating that certain paleosols actually represent unconformities. Some of the soils were developed on old land surfaces where deposition was practically at a standstill …


Amount And Chemical Composition Of The Organic Matter Contributed By Overstory And Understory Vegetation To Forest Soil, David Robert Main Scott Jan 1955

Amount And Chemical Composition Of The Organic Matter Contributed By Overstory And Understory Vegetation To Forest Soil, David Robert Main Scott

Yale School of the Environment Bulletin Series

No abstract provided.


38th Annual Meeting, 1954. Abstracts Of Papers, Academy Editors Jan 1955

38th Annual Meeting, 1954. Abstracts Of Papers, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


38th Annual Meeting, 1954. Program, Academy Editors Jan 1955

38th Annual Meeting, 1954. Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


38th Annual Meeting, 1954. Secretary's Report, Lowell F. Bailey Jan 1955

38th Annual Meeting, 1954. Secretary's Report, Lowell F. Bailey

Journal of the Arkansas Academy of Science

No abstract provided.


Age And Length Of Menhaden (Brevoortia Tyrannus) In The Waters Of Chesapeake Bay, With Comments On The Rate Of Growth, Ray T. Oglesby Jan 1955

Age And Length Of Menhaden (Brevoortia Tyrannus) In The Waters Of Chesapeake Bay, With Comments On The Rate Of Growth, Ray T. Oglesby

Dissertations, Theses, and Masters Projects

No abstract provided.


Succession In A Dune Community At Mentor Headlands, Ohio, Harold G. Marshall Jan 1955

Succession In A Dune Community At Mentor Headlands, Ohio, Harold G. Marshall

Biological Sciences Faculty Publications

Continual sand deposition on the Lake Erie shore, adjacent to the mouth of the Grand River, has led to the formation of a developing sand dune community and through the years a successional pattern of plant growth. An analysis was made of the general plant composition of the area by means of four transects directed from the bare beach inland. Definite zonation of specific plant species was present throughout the community in parallel formation. Named for the dominant plant types they contained, the major stages were: dune grass, poplar, aspen, and oak.


Abstract Papers May 1954

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


Abstract Papers May 1954

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.