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A Comparison Of Various Sizes Of Inverted Vials Used In Durham Fermentation Tubes., Blanche Mae Welsh Jan 1940

A Comparison Of Various Sizes Of Inverted Vials Used In Durham Fermentation Tubes., Blanche Mae Welsh

Electronic Theses and Dissertations

No abstract provided.


The Influence Of Nutrition On Sporangial Formation In Araiospora Streptandra., Richard Curtis Webster Jan 1940

The Influence Of Nutrition On Sporangial Formation In Araiospora Streptandra., Richard Curtis Webster

Electronic Theses and Dissertations

No abstract provided.


The Mammalian Erythrocyte, H.J. Werner Jun 1939

The Mammalian Erythrocyte, H.J. Werner

Bachelors’ Theses

An investigation of bibliographies shows that the red corpuscles of the blood have been studied very extensively, in fact, wore so than any cell in the mammalian body. The study has progressed vigorously and from varied points of view.


A Contribution To The Knowledge Of The Minnesota Flora, John W. Moore Apr 1939

A Contribution To The Knowledge Of The Minnesota Flora, John W. Moore

Journal of the Minnesota Academy of Science

No abstract provided.


Growth Substances And Nutrition Of Protozoa, Alfred M. Elliott Apr 1939

Growth Substances And Nutrition Of Protozoa, Alfred M. Elliott

Journal of the Minnesota Academy of Science

No abstract provided.


Ecological Study Of The Weed Population Of Eastern Nebraska, Elva L. Norris Jan 1939

Ecological Study Of The Weed Population Of Eastern Nebraska, Elva L. Norris

University Studies (University of Nebraska) (1888–1984)

EXACT knowledge of the relations existing between weeds and cultivated crops is very limited. This is true also of the amount of viable weed seed present in arable soil. Impressions and observations have been recorded, but very few quantitative investigations have been made. The numerous circulars and bulletins about weeds, issued by many experiment stations, deal mostly with descriptions of species and methods of weed control. The present research was undertaken primarily to determine the relationship which exists between weeds and cultivated crops, but also to obtain an estimation of the number of viable weed seeds present in the soil. …


The Efficiency Of Churn Washing Method And The Keeping Quality Of Butter As Indicated By Yeast And Mold Counts, T. Allen Evans Jan 1939

The Efficiency Of Churn Washing Method And The Keeping Quality Of Butter As Indicated By Yeast And Mold Counts, T. Allen Evans

Electronic Theses and Dissertations

Of all the equipment used in the manufacture of butter, no single piece has as close contact with the finished product as does the churn while at the same time no piece of equipment is more difficult to keep properly cleaned. The workers in the dairy industry have expended much time and effort attempting to build a churn which could be kept in a more satisfactory state, especially from a bacteriological point of view. As yet no satisfactory material for churn construction has been found to replace wood which at best is difficult to keep free of micro-organisms. Since it …


The Spinal Nerves And Spinal Cord Of The Frog, Laverne A. Penn Sep 1938

The Spinal Nerves And Spinal Cord Of The Frog, Laverne A. Penn

Bachelors’ Theses

The common grass frog, Rana pipiens as wall as the bull frog, Rana catesbiana have served during many decades as material from which both the student of zoology and the investigator in biological problems have gathered valuable information about the anatomy and physiology of the common systems. Among these systems the central, peripheral, and sympathetic nervous system plays a coordinating role, because of the ramifying nature of its organization. It is the purpose of this thesis to investigate the gross and histological structure of these branches known as spinal nerves. When one inspects the literature on the nervous system of …


Wound Healing In Potatoes (Triumph Variety) As Influenced By Type Of Injury, Nature Of Initial Exposure, And Storage Conditions, H. O. Werner Jul 1938

Wound Healing In Potatoes (Triumph Variety) As Influenced By Type Of Injury, Nature Of Initial Exposure, And Storage Conditions, H. O. Werner

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Tubers of the Triumph variety of potatoes, the one most extensively grown in western Nebraska, are more susceptible than those of other varieties to the various types of injury that occur at harvest time. This greater susceptibility is chiefly the result of long stolons, unusual tenderness of skin, and ease with which the tubers crack. The two latter characteristics have been accentuated by the custom of late planting adopted generally throughout the region in recent years. Many of the difficulties could be avoided by growing another variety. However, as there now seems to be no other variety as well adapted …


The Lungs And Respiration In The Frog, Peter P. Strassburg Jun 1938

The Lungs And Respiration In The Frog, Peter P. Strassburg

Bachelors’ Theses

In a wide sense, respiration is sometimes defined as the gaseous exchange constantly taking place between an organism and its environment. Essentially it is concerned with the intake of oxygen and the output of carbon dioxide but it also includes any other gas exchange that might occur. Small organisms take oxygen directly from the air or from the watery medium surrounding them into all parts of their structures. They also give off carbon dioxide from all their parts directly into the surrounding medium. They can do this successfully because they are small enough to have every cell in direct or …


A Cytological Study Of The Ciliated Epithelium Of Nucula Castrensis Hinds., Dorothy Blumer Jun 1938

A Cytological Study Of The Ciliated Epithelium Of Nucula Castrensis Hinds., Dorothy Blumer

Electronic Theses and Dissertations

Ever since the latter part of the 17th century, when ciliary movement was first observed, the study of ciliated cells has been of great interest to biologists, particularly to physiologists. In 1713 Leeuwenhoek recorded some observations he made on ciliary activity, using his primitive microscope. A knowledge of the structure and function of ciliated cells is also of importance in that branch of medicine pertaining to disorders of the respiratory passages and the movement of the ovum in the uterine tubes. The bivalve molluscs have come to be the classical example for the study of ciliated cells, both because of …


Pituitary Gland Of Frog, Harold Joseph May 1938

Pituitary Gland Of Frog, Harold Joseph

Bachelors’ Theses

The endocrine or ductless gland system is one of the most important systems in the body of the vertebrates. The glands which comprise this system are the pancreas, which produces the insulin hormone; the thyroid, which secretes the throxin hormone; the parathyroid which produces the hormone known as the para-thormone; the adrenal glands which secretes cortin and adrenalin; the pineal gland about which very little is known; and the pituitary gland which produces many hormones, two of which, tethelin and pituitrin, are of great physiological importance. These hormones pass directly into the blood or lymph vessels and enter the circulatory …


The Anatomy, Physiology, And Histology Of The Musculature Of The Pelvic Appendages Of Rana Catesbiana, Wilfred F. Horner May 1938

The Anatomy, Physiology, And Histology Of The Musculature Of The Pelvic Appendages Of Rana Catesbiana, Wilfred F. Horner

Bachelors’ Theses

The muscles of the frog leg have been worked on very extensively during the last thirty-five years. The reason the frog has been subjected to such an extensive study in research is the fact of its striking resemblances to man and also the fact that they are plentiful and easy to work with in all types of experiments. The structures of a frog are well developed and prove very efficient for study.

This specific field of work was picked for this thesis because of the interest to the author, the mag­nitude of work done in the field, and the importance …


The Chemical Nature And Distribution Of Black Pigment In Soil, William Sherman Gillam Jan 1938

The Chemical Nature And Distribution Of Black Pigment In Soil, William Sherman Gillam

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

As used in this paper, humus refers to that portion of the soil organic matter peptized by four per cent ammonium hydroxide. That fraction peptized by four per cent ammonium hydroxide, precipitated by acids, and insoluble in alcohol, is designated as black pigment. It is called humic soil by many writers.


Color Phases In Helicina Orbiculata Tropica 'Jan' Pfr., E. P. Cheatum, Betty Watt Brooks Nov 1937

Color Phases In Helicina Orbiculata Tropica 'Jan' Pfr., E. P. Cheatum, Betty Watt Brooks

Field and Laboratory

An interesting shell-color phase occurs in Helicina orbiculata tropica ’Jan.’ Pfr., a small land snail found in abund ance in northeastern, southern, and central Texas. Pilsbry and Ferris have noted color variations in this species, stating that "some colonies are all white; others are mingled with red or blue shells".


Comparative Physiology Of Actinomyces In Relation To Potato Scab, Mitrofan M. Afanasiev Aug 1937

Comparative Physiology Of Actinomyces In Relation To Potato Scab, Mitrofan M. Afanasiev

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The present work was undertaken with the purpose of investigating the physiology of different strains of A. scabies as compared with saprophytic Actinomyces. By a comparative study of these groups, it was thought that differences in the physiology of the two might be found which would give a better understanding of the nature of this parasitism and also of the metabolism of Actinomyces in general. In addition, it was hoped that the determination of the factors influencing the parasitism of Actinomyces might establish a basis for the development of more efficient methods of controlling scab diseases. The present investigation …


The Influence Of Soil Profile Horizons On Root Distribution Of White Pine (Pinus Strobus), Harold J. Lutz, Joseph B. Ely Jr., Silas Little Jr. Jan 1937

The Influence Of Soil Profile Horizons On Root Distribution Of White Pine (Pinus Strobus), Harold J. Lutz, Joseph B. Ely Jr., Silas Little Jr.

Yale School of the Environment Bulletin Series

No abstract provided.


The Skeletal, Muscular, Vascular, And The Digestive Systems Of The Ferret (Mustela Putorius) And A Comparison Of These Systems With Those Of The Domestic Cat (Felis Domesticus)., Arthur Pincus Skwerer Jan 1937

The Skeletal, Muscular, Vascular, And The Digestive Systems Of The Ferret (Mustela Putorius) And A Comparison Of These Systems With Those Of The Domestic Cat (Felis Domesticus)., Arthur Pincus Skwerer

Electronic Theses and Dissertations

No abstract provided.


Weeds In Sacramento County Of California, Ross Clover Jan 1937

Weeds In Sacramento County Of California, Ross Clover

University of the Pacific Theses and Dissertations

Sacramento County has many types of Agriculture and many weed pests which compete with the crops. Stock may be poisoned by certain weeds and weeds may also act as hosts for fungus diseases, virus diseases and insect pests of cultivated crops. Many plants may be weeds in one locality and harmless or beneficial in other parts. The author has made a thorough study of the country's agriculture and its weeds. Latest control practices were also studied.


The Flora Of The Tasco Lake Region, Sheridan County, Kansas, Raymond W. Darland May 1936

The Flora Of The Tasco Lake Region, Sheridan County, Kansas, Raymond W. Darland

Master's Theses or Doctor of Nursing Practice

It has been customary in writing theses dealing with taxonomic problems to collect data from an entire county. Having had occasion to collect botanical specimens from the Tasco Lake for work in biology at the Sheridan High School, the wealth of plant life to be found here became apparent. The area ranges from xerophytic forms on the uplands to the hydrophytic forms in the lake and marshes. Many of the latter have never been reported from Western Kansas. Collections in preserving fluid were made of the water forms found and specimens of the landforms were mounted on regulation-sized sheets properly …


Nutritional Studies Of Protozoa, Alfred M. Elliott Jan 1936

Nutritional Studies Of Protozoa, Alfred M. Elliott

Journal of the Minnesota Academy of Science

No abstract provided.


Bulletin No. 2: The Connecticut Arboretum At Connecticut College, New London, George S. Avery Jr., Katharine Matthies, Katharine Blunt, C B. Graves, Katherine Floyd May 1935

Bulletin No. 2: The Connecticut Arboretum At Connecticut College, New London, George S. Avery Jr., Katharine Matthies, Katharine Blunt, C B. Graves, Katherine Floyd

Bulletins

No abstract provided.


The Circulatory System In The Extremities Of The Domestic Cat From A Gross Anatomical Standpoint, Harold Liebenstein May 1935

The Circulatory System In The Extremities Of The Domestic Cat From A Gross Anatomical Standpoint, Harold Liebenstein

Bachelors’ Theses

The mammalian circulatory system serves the prime purpose of furnishing the body with food to carry on its functions. The domestic cat is closely related anatomically and physiologically to the human being, which makes it an excellent animal for laboratory work or experimental purposes.


Bulletin No. 252 - Groundwater: Part I: Fundamental Principles Governing Its Physical Control, Willard Gardner, T. R. Collier, Doris Farr Nov 1934

Bulletin No. 252 - Groundwater: Part I: Fundamental Principles Governing Its Physical Control, Willard Gardner, T. R. Collier, Doris Farr

UAES Bulletins

This article does not purport to present detailed specifications for engineering structures nor to enlighten engineers specifically as to devices or methods appropriate to the control of groundwater. It is the aim rather to discuss fundamental principles and to indicate applications.


Molasses-Agar: A Useful Medium For The Cultivation Of The Genus Monilia, Hardy A. Kemp, Sol Haberman Nov 1934

Molasses-Agar: A Useful Medium For The Cultivation Of The Genus Monilia, Hardy A. Kemp, Sol Haberman

Field and Laboratory

Species of the genus Monilia are easily cultivated be­tween the temperatures of 22°C and 38°C on solid media of slightly acid reaction. After cultivating stock strains of Monilia albicans and Monilia psilosis on Sabouraud's medium, honey agar, and molasses agar, it was found that molasses agar afforded the best means for cultivating these Oosporaceae.


Rainfall On The Western Front During The World War, Edwin J. Foscue Nov 1934

Rainfall On The Western Front During The World War, Edwin J. Foscue

Field and Laboratory

Within the last fifty years many attempts have been made to produce rain by artificial means, but all have resulted in failures. The unusually dry summer of 1934 in central United States, from North Dakota to Texas, produced a new group of rainmakers and rain-making experiments. The details of their plans differed somewhat, but all worked on the so-called "concussion theory" that the detonation of high explosives in the upper atmosphere would produce rain. In each case claims were supported by the commonly accepted statement that rain always followed battles, and that the unusually heavy rain in France along the …


Bacteria & Nitrate Nitrogen Content Of The Water Of Barren River, Gilbert Westerfield Aug 1934

Bacteria & Nitrate Nitrogen Content Of The Water Of Barren River, Gilbert Westerfield

Masters Theses & Specialist Projects

A quantitative study of bacteria and nitrogenous compounds of Barren River in Warren County, Kentucky, was undertaken to determine the relation between the number of bacteria and the amount of nitrate nitrogen found.


Studies On A Cave Fish Of Uncertain Classification, Jennie Miller Orr Aug 1934

Studies On A Cave Fish Of Uncertain Classification, Jennie Miller Orr

Masters Theses & Specialist Projects

The specimens studied during this investigation were taken incidentally during a general faunal survey of certain peculiar streams flowing from underground channels. On casual examination it was evident that they belonged to the cave fish group but were not the well known almost colorless blind variety. After checking the descriptions in various vertebrate manuals it appeared that they were probably a new species.

There are three groups of cave fishes, the non-blind, the semi-blind and the blind. Chologaster, or the Rice Field Minnows of South Carolina, are members of the non-blind group. Forbesichthys of southern Illinois and Kentucky is an …


The Effect Of The Nitrogen Fixation And Of Aeration Upon The Growth Of Yeast In Culture Media, Syrene C. Bernstein May 1934

The Effect Of The Nitrogen Fixation And Of Aeration Upon The Growth Of Yeast In Culture Media, Syrene C. Bernstein

Bachelors’ Theses

The subject of yeast has been widely studied from many viewpoints; we can find many bacteriological, physiological, and chemical papers on the subject. Besides the purely scientific work on yeast, there are numerous industrial investigations on this subject, since yeast growth and the products of yeast growth form the foundation for such important industries as the distilling, brewing, baking industries as well as commercial yeast manufacture. The effect of nitrogen fixation has been treated from all of these angles, scientific and industrial, and the investigations include the form in which the nitrogen is most easily assimilated, the manner of the …


Cephalosporium Wilt And Die-Back Of The White Elm, R. W. Goss, Paul Raymond Frink Jan 1934

Cephalosporium Wilt And Die-Back Of The White Elm, R. W. Goss, Paul Raymond Frink

Nebraska Agricultural Experiment Station: Historical Research Bulletins

A new disease of the white elm has been found to be common in eastern Nebraska. The causal organism has been isolated and its pathogenicity proved by inoculation. The fungus belongs to the genus Cephalosporium and is considered to be the same as that described by Curtis May of Ohio and found by him in specimens obtained in Iowa, Missouri, New York, and Washington, D.C. The morphology and cultural characters of the organism are described.