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Colorless Fuchsin: A Staining Technique For The Salivary Gland Chromosomes Of Drosophila Melanogaster, Gordon I. Koehler May 1942

Colorless Fuchsin: A Staining Technique For The Salivary Gland Chromosomes Of Drosophila Melanogaster, Gordon I. Koehler

Bachelors’ Theses

The chromosome theory of heredity opened a large field for both cytologists and geneticists. They looked to the day when someone would find an organism in which the chromosomes were so large that it would be possible to see Qualitative differences along their length corresponding to the different genes which they knew must be present at these points. Before 1932, methods and materials to show these chromosomes to any appreciable extent had, however, not yet been devised. Competent observers using the finest of optical equipment, and the most refined techniques of staining could see little at the time of nuclear …


Competition Of Western Wheat Grass With Relict Vegetation Of Prairie, J. E. Weaver May 1942

Competition Of Western Wheat Grass With Relict Vegetation Of Prairie, J. E. Weaver

Department of Agronomy and Horticulture: Faculty Publications

Many profound changes in mid-continental grasslands have resulted from the recent extended drought. In the prairies of eastern Nebraska, Kansas and South Dakota, the earlier continuous stands of bluestem (Andropogon scoparius and A. furcatus) have often been greatly fragmented and now occur as relict patches a few square feet to many square rods in extent. Loss of approximately 95 per cent of little bluestem has left the prairie cover very open. Over large areas, except for weeds and a few surviving grasses and forbs, the soil was bared (Weaver, Stoddart and Noll, 1935; Weaver and Albertson, 1939). Grasses …


A Study Of The Ring-Necked Pheasant (Phasianus Colchicus Torquatus Gmelin) In Northern Utah, William T. Mckean May 1942

A Study Of The Ring-Necked Pheasant (Phasianus Colchicus Torquatus Gmelin) In Northern Utah, William T. Mckean

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Purpose of Study. The ring-necked pheasant (Phasianus colchicus torquatus Gmelin) is well enough known to need no introduction. It is at present undoubtedly the most abundant and most important gallinaceous game bird in northern Utah. Its abundance and its occurrence in agricultural areas has stimulated much general interest. Yet, aside from two food habits studies, both conducted in Utah County, no intensive research has been made into its ecological relationships or its general life history in Utah.

In order to formulate sound management plans for the pheasant in Utah, the Utah Cooperative Wildlife Research Unit has felt the need …


The Scientist's Concept Of The Physical World, Willard Gardner Apr 1942

The Scientist's Concept Of The Physical World, Willard Gardner

Faculty Honor Lectures

To those who are aesthetic, there is perhaps nothing more inspiring than a beautiful sunset, with brilliant colors above the horizon and with banks of dark clouds above, set in the deep blue of the heavens, or the brilliant hues of the rainbow forming a halo about the majestic mountain with its coat of green, purple, brown, or gray. By these things are the emotions stirred.

The physicist too is emotional but he.is also at times realistic. He becomes sentimental but he also seeks to explain the behavior of nature. By means of devices and instruments his perceptual world is …


Kentucky Warbler (Vol. 18, No. 2), Kentucky Library Research Collections Apr 1942

Kentucky Warbler (Vol. 18, No. 2), Kentucky Library Research Collections

The Kentucky Warbler

No abstract provided.


One Hundred Studies Of The Calcium, Phosphorus, Iron, And Nitrogen Metabolism And Requirement Of Young Women, Ruth M. Leverton, Alice G. Marsh Apr 1942

One Hundred Studies Of The Calcium, Phosphorus, Iron, And Nitrogen Metabolism And Requirement Of Young Women, Ruth M. Leverton, Alice G. Marsh

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The present study was undertaken to add appreciably to the data available on the metabolism of calcium, phosphorus, iron, copper, and nitrogen of young women on their customary self-chosen diets. It was planned to use the figures for the retentions or losses of these dietary essentials which occurred at various levels of intake to determine the requirement of the subjects and to evaluate the adequacy of present adult dietary standards for young women. The fact that the girls were living on self-chosen diets warrants emphasis. A large proportion of the subjects were doing light housekeeping and brought much of their …


Plant Diseases Common, Destructive, Preventable In South Dakota, W.F. Buckhholtz Apr 1942

Plant Diseases Common, Destructive, Preventable In South Dakota, W.F. Buckhholtz

Agricultural Experiment Station Plant Pathology Pamphlets (1942-1962)

Abundant agricultural production is a victory goal and in South Dakota is based on an abundance of feed, forage and cash field crops and an adequate home vegetable and fruit supply. On the other hand, soil conservation and the maintenance of South Dakota’s agricultural productivity depends on a practice of moderate rather than wholesale over-cropping of cultivated land. Shortages of labor and machinery place a definite limit on the amount of really good farming that can be done it South Dakota for the duration of the war. One of the ways to insure maximum crop production from a minimum of …


Some Aspects Of Evolutionary Theory, George M. Robertson Jan 1942

Some Aspects Of Evolutionary Theory, George M. Robertson

Fort Hays Studies Series

The present contribution is not a unified account, but is a series of essays dealing with some aspects, but is a series of essays dealing with some aspects of evolutionary theory.


The Incidence Of Trichinella Spiralis In The Diaphragms Of Swine From The Louisville Abattoirs., Stuart Lyle Adams Jan 1942

The Incidence Of Trichinella Spiralis In The Diaphragms Of Swine From The Louisville Abattoirs., Stuart Lyle Adams

Electronic Theses and Dissertations

Trichinosis is a disease caused by the parasitic nematode Trichinella spiralis. When meat containing encysted larvae is consumed the cysts are dissolved by the action of the gastric juice in the stomach and the larvae migrate to the intestine where they mature, copulate and give birth to living young within a week of the original infection. The larvae enter the lymph spaces and are carried to the thoracic duct from which they reach the venous circulation and thence the arterial circulation by way of the heart and the pulmonary capillaries. From the arterial blood the larvae enter most of the …


Nebraska Bird Review (January-June 1942) 10(1), Whole Issue Jan 1942

Nebraska Bird Review (January-June 1942) 10(1), Whole Issue

Nebraska Bird Review

Contents

Myron Harmon Swenk, A Biography, By Harry C. Oberholser.. 1

Distribution and Migration of the Solitary Sandpiper in Nebraska, By Myron H. Swenk and Edson Fichter.............. 15

Minutes of the Forty-third Annual Meeting ....................... 22

Report on the Fortieth Annual Field Day ...................................... 25

General Notes ....................................................................................... 30


An Economic Study Of Rough Rice Marketing In Louisiana., Clarence Boonstra Jan 1942

An Economic Study Of Rough Rice Marketing In Louisiana., Clarence Boonstra

LSU Historical Dissertations and Theses

No abstract provided.


Threonine Deficiency In Hydrolysates Of Zein Prepared By Autoclaving, Raymond Borchers, John R. Totter, Clarence P. Berg Jan 1942

Threonine Deficiency In Hydrolysates Of Zein Prepared By Autoclaving, Raymond Borchers, John R. Totter, Clarence P. Berg

Department of Biochemistry: Faculty Publications

In a previous paper (Borchers and Berg, 1942) we showed that

autoclaving zein with sulfuric acid longer than necessary for complete

hydrolysis causes destruction and racemization; either of

these might account for the failure of such a hydrolysate to

promote growth in young rats when substituted for a hvdrolysate,

prepared by refiuxing, in a diet which produced moderate growth.

It seemed to us that this deterioration in the dietary protein might

well be the result primarily of essential amino acid deficiencies

which could be detected and overcome by appropriate supplementation.

Because threonine is known to be present in zein in …


The Effect Of Conditions Of Hydrolysis And Of Prolonged Heating Upon The Optical Rotation Of Sulfuric Acid Hydrolysates Of Zein, Raymond Borchers, Clarence P. Berg Jan 1942

The Effect Of Conditions Of Hydrolysis And Of Prolonged Heating Upon The Optical Rotation Of Sulfuric Acid Hydrolysates Of Zein, Raymond Borchers, Clarence P. Berg

Department of Biochemistry: Faculty Publications

Some time ago we observed that a sulfuric acid hydrolysate of zein prepared in an autoclave at 165˚ did not support growth in young rats when it was supplemented with certain amino acids, even though the same amino acids, added to a hydrolysate prepared by refluxing, permitted moderate growth. Since the optical rotation of the autoclaved hydrolysate was lower than that of the refluxed, either destruction or racemization of essential constituents, or both, might have occurred. Loss of amino nitrogen and production of extra ammonia upon prolonged autoclaving of proteins with acids have been noted by Van Slyke (1912) …


Geology Of Dallas County Texas, Claude C. Albritton Jr. Dec 1941

Geology Of Dallas County Texas, Claude C. Albritton Jr.

Field and Laboratory

At the regular monthly noon meeting of the Dallas Petroleum Geologists on Monday, May 5, 1941, a motion was passed authorizing the president to appoint a committee to work on a project which would culminate in a bulletin on the geology of Dallas County, Texas, to be in printed form prior to the annual meeting of the American Association for the Advancement of Science to be held in Dallas, Texas from December 29, 1941 to January 3, 1942. Those members appointed to the general committee were Messrs. C. C. Albritton, Jr. of Southern Methodist University, Robert I. Seale of Schlumberger …


The Relation Of Temperature To The Embryonic And Nymphal Development Of The Differential Grasshopper Melanoplus Differentialis Thomas, Myron H. Swenk, Charles H. Bratt Nov 1941

The Relation Of Temperature To The Embryonic And Nymphal Development Of The Differential Grasshopper Melanoplus Differentialis Thomas, Myron H. Swenk, Charles H. Bratt

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Temperature plays the major role in the regulation of the rate of embryonic development of the differential grasshopper (Melanoplus differentialis Thomas).


Babcock Testing And Other Methods Of Analyzing Dairy Products, L. K. Crowe Sep 1941

Babcock Testing And Other Methods Of Analyzing Dairy Products, L. K. Crowe

Nebraska Agricultural Experiment Station: Historical Circulars

The manufacturing of dairy products on a commercial scale began about the middle of the nineteenth century and was greatly stimulated by the development of the centrifugal cream separator in the late eighties. The invention of the Babcock test in the early nineties overcame some of the difficulties that had developed in paying for milk upon its butterfat content, since it was early recognized that milk varied widely in that respect.


Judging Quality In Dairy Products, P. A. Downs Sep 1941

Judging Quality In Dairy Products, P. A. Downs

Nebraska Agricultural Experiment Station: Historical Circulars

In the dairy industry increasing attention is being paid to the question of quality of products. The well established system of buying and selling butter and cheese on the basis of quality by score or grade is practiced in the principal markets of the world. The other dairy products, while not marketed by score, are receiving more and more attention in this respect. As more information becomes available and the judging better standardized, other dairy products will doubtless be sold by grade.


The Geographic Distribution Of Azotobacter And Rhizobium Meliloti In Nebraska Soils In Relation To Certain Environmental Factors, H. B. Peterson, T. H. Goodding Jun 1941

The Geographic Distribution Of Azotobacter And Rhizobium Meliloti In Nebraska Soils In Relation To Certain Environmental Factors, H. B. Peterson, T. H. Goodding

Nebraska Agricultural Experiment Station: Historical Research Bulletins

In this investigation a survey of Nebraska soils has been made in order to determine the distribution of the aerobic nonsymbiotic and symbiotic nitrogen fixers of the genera Azotobacter and Rhizobium respectively. In connection with this survey, some of the characteristics of the soils which may bring about this distribution were studied. Up to this time practically no research has been reported on the microflora of the soils of Nebraska. Hence there is little basis for predicting the activity of these organisms under environmental conditions as they exist here. It is hoped that this work will not only supply some …


The Economic And Physiological Significance Of The Effect Of Rootone On Dutch White Clover, Mary Alice Lord May 1941

The Economic And Physiological Significance Of The Effect Of Rootone On Dutch White Clover, Mary Alice Lord

Biology Honors Papers

This 35 page thesis examines the effect of the synthetic growth hormone Rootone on the Dutch White Clover plant.


The Finishing Of The Stained Slide: A Discussion Of The Various Mounting Media And A Brief Excursion Into The Newer Substitutes For Cover Glasses, Jean Clawson May 1941

The Finishing Of The Stained Slide: A Discussion Of The Various Mounting Media And A Brief Excursion Into The Newer Substitutes For Cover Glasses, Jean Clawson

Biology Honors Papers

This 32 page thesis examines steps in the preparation of microscopic slides, the choice and history of various slide media and substitutes for cover glasses.


Artificial Parthenogenesis In Rana Pipiens, Frank A. Lippi Jr. May 1941

Artificial Parthenogenesis In Rana Pipiens, Frank A. Lippi Jr.

Biology Honors Papers

This 39 page thesis provides a history of artificial parthenogenetic experiments and examines the technique by using frogs' eggs.


A Celestial Globe, John D. Boon May 1941

A Celestial Globe, John D. Boon

Field and Laboratory

Nature is deceptive. Things that appear to be true are often untrue. This point is well illustrated in the science of astronomy. The history of astronomy is strewn with rejected theories that were once held by wise men. Even today many false theories that should have been discarded long ago are believed by many people. Why is this true?


A Study Of The Physiology Of Grape Roots And Stocks In Relation To A Lime-Induced Chlorosis, Eldrow Reeve May 1941

A Study Of The Physiology Of Grape Roots And Stocks In Relation To A Lime-Induced Chlorosis, Eldrow Reeve

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The word chlorosis comes from the Greek "chloros" meaning light green and is used by plant science workers to designate a disease of plants, the characteristic symptom of which is the yellowing of the leaves.


Fifty-Fifth Annual Meeting Of The Iowa Academy Of Science And The Tenth Annual Convention Of The Junior Academy Of Science Of Iowa, April 25 And 26, 1941, Iowa Academy Of Science Apr 1941

Fifty-Fifth Annual Meeting Of The Iowa Academy Of Science And The Tenth Annual Convention Of The Junior Academy Of Science Of Iowa, April 25 And 26, 1941, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Observations On Vitrified And Frozen Muscle Fibers In Polarized Light, Gregory Thoennes Apr 1941

Observations On Vitrified And Frozen Muscle Fibers In Polarized Light, Gregory Thoennes

Journal of the Minnesota Academy of Science

No abstract provided.


Nutrition Of The Wax Moth Larvae. Vitamin Requirement. I. Requirement For Vitamin B, Mykola H. Haydak Apr 1941

Nutrition Of The Wax Moth Larvae. Vitamin Requirement. I. Requirement For Vitamin B, Mykola H. Haydak

Journal of the Minnesota Academy of Science

No abstract provided.


Hardiness Of Woody Plants In Minnesota, H. E. Stork Apr 1941

Hardiness Of Woody Plants In Minnesota, H. E. Stork

Journal of the Minnesota Academy of Science

No abstract provided.


A Study Of Subspecific Variation In The Richardson Pocket-Gopher (Thomomys Talpoides) In Nebraska, With Descriptions Of Two New Subspecies, Myron H. Swenk Mar 1941

A Study Of Subspecific Variation In The Richardson Pocket-Gopher (Thomomys Talpoides) In Nebraska, With Descriptions Of Two New Subspecies, Myron H. Swenk

University of Nebraska State Museum: Mammalogy Papers

There has been little published evidence of the occurrence of pocket gophers of the genus Thomomys in Nebraska.

Thomomys talpoides pierreicolus subsp. nov

Pierre Richardson Pocket-Gopher

Thomomys talpoides cheyennensis subsp. nov.

Cheyenne Richardson Pocket-Gopher


Bulletin No. 295 - Comparison Of Two Methods Of Determining Wool Density, Milton A. Madsen, Ralph W. Phillips, John V. Christensen, Roy L. Henrie Jan 1941

Bulletin No. 295 - Comparison Of Two Methods Of Determining Wool Density, Milton A. Madsen, Ralph W. Phillips, John V. Christensen, Roy L. Henrie

UAES Bulletins

Density of the fleece is one of the primary factors determining the wool-producing capacity of the sheep. Sheepmen have attempted to evaluate density by handling the fleece. This method is not sufficiently refined for use in experimental work, and may be subject to errors and misinterpretations. For example, if two fleeces are alike in density and diameter of fibers, yet differ in length, the longer fleece will feel less dense. If, on this basis, the sheep with the fleece that appeared most dense were selected for breeding, selection would be away from the longer fleece. Any method that can be …


Wildlife Of The Atlantic Coast Salt Marshes, W. L. Mcatee Jan 1941

Wildlife Of The Atlantic Coast Salt Marshes, W. L. Mcatee

United States Fish and Wildlife Service: Publications

Salt marshes of the Atlantic coast have been formed under the opposed tendencies of sinking of the land and of its upbuilding by silt and sand. The plants that form the marshes occupy zones largely determined by the degree of inundation by tides. Eelgrass entirely submerged, smooth cordgrass regularly washed by the tide, and marsh hay covered only by exceptionally high water are characteristic plants. Each zone is the home or feeding area of certain kinds of wildlife. The appearance, distribution, and habits of the more common species are described, and general wildlife conservation is urged. This circular, which is …