Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Life Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 111481 - 111510 of 114030

Full-Text Articles in Entire DC Network

Artificial Parthenogenesis In Rana Pipiens, Richard V. Frohner May 1940

Artificial Parthenogenesis In Rana Pipiens, Richard V. Frohner

Biology Honors Papers

This 9 page thesis attempts to prove that development of a frog's egg may be initiated by a mechanical force alone, that this development is materially aided by a chemical agent, and to suggest the possible significance of each step to aid further investigation.


A Histological Comparison Of The Small Intestine Of The Frog And Man, Eli Getch May 1940

A Histological Comparison Of The Small Intestine Of The Frog And Man, Eli Getch

Bachelors’ Theses

Without the aid of a microscope, Bichat in 1800 studied tissues of various parts of the body, and, even though he did not make any cellular sketches, his work laid the foundation for histology. Then after the announcement of the cell theory by Schleiden and Schwann in 1839, a new path opened for histological study. Leydig (1864) applied the histology of that day to the lower animals. Cajal (1906) cleared up the complicated relations of the tissues together with a complete investigation of the nervous system.


A Study Of The Skeletal System Of Emys Blanding Turtle, Joseph M. Mosovsky May 1940

A Study Of The Skeletal System Of Emys Blanding Turtle, Joseph M. Mosovsky

Bachelors’ Theses

The turtles have a bony investment or shell, into which the legs, head, and tail maybe drawn. In some turtles there is a hinge on the lower part of the shell that enables the animal to enclose itself more completely. Turtles which have no way of defending themselves other than by their shells have a well developed plastron and carapace for protection, but our vicious friend the snapping turtle whom nature has provided with powerful jaws and muscles has a comparatively small plastron. The marine turtles have the limbs fin-like, indicating their aquatic life. The land turtles have them short …


The Effects Of An Insufficient Carbohydrate Diet On The Leucocytes Of The Normal Albino Rat, Carl Frederick Glienke May 1940

The Effects Of An Insufficient Carbohydrate Diet On The Leucocytes Of The Normal Albino Rat, Carl Frederick Glienke

Bachelors’ Theses

This thesis deals with the effects of an insufficient carbohydrate diet on the differential counts of the leucocytes of the common albino rat. The experiment was chosen because of the interesting problem it presented and because little could be found on work done regarding it. To the ’writer’s knowledge, very little work has been done in even establishing a definite differential count of a normal rat, much less working on one under an abnormal condition. Because of this lack of information, a normal count was first established for the strain used, and then this count was compared with that of …


A Cytological Study Of The Intestinal Glandular Epithelium, Mary Judelle Zuiker May 1940

A Cytological Study Of The Intestinal Glandular Epithelium, Mary Judelle Zuiker

Bachelors’ Theses

Continuing from the stomach, the digestive tract becomes a smaller tube whose internal surface is much increased by means of folds--the plica circularis, the villi, and crypts of Lieberkühn. The plica (formerly known as valvulae conniventes) are really elevations of the submucosa covered on both sides by the entire mucous membrane-villi, glands, and muscularis mucosae. The mucosa membrane, or tunica mucosa, is lined by simple columnar epithelium in which many goblet cells are present, particularly in the deeper folds. The basement membrane, as well as the muscularis mucosa, are identical with those of the stomach.


Heterochromia Iridis From The Genetical Viewpoint, Richard Charles Suehr May 1940

Heterochromia Iridis From The Genetical Viewpoint, Richard Charles Suehr

Bachelors’ Theses

It is intended in this paper to present the published data obtainable; to report original data; to analize this data; and to try to establish some law of heredity by which the phenomenon of Heterochromia Iridis is transmitted from generation to generation.


Resistance To Staphylococcus Aureus In White Rats, Robina B. Langill May 1940

Resistance To Staphylococcus Aureus In White Rats, Robina B. Langill

Bachelors’ Theses

An investigation of bibliographies shows that staphylococcus aureus in its pathogenic potentialities has been extensively investigated from varied points of view and with frequently conflicting results.

Staphylococcus aureus is most frequently associated with furuncles, wound infection, and minor skin abcesses. Occasionally, however, due to extreme lowered resistance or other conditions not fully understood, staphylococcus causes a septicaemia which is attended by an 80% mortality rate. Post-mortem examinations of the victims of such septicaemia show an extensive invasion of all organs of the body by the bacteria but more particularly a hyperplasia of the lymph nodes, the spleen and thymus, indicating …


Reflex Action In The Earthworm, As A Typical Example Of The Annelids, Morris L. Yoder Jr. May 1940

Reflex Action In The Earthworm, As A Typical Example Of The Annelids, Morris L. Yoder Jr.

Biology Honors Papers

This 18 page thesis discusses the anatomy of the earthworm and importance of reflex actions, including responses to various stimuli and the role of the nerve cord.


A Survey Of Human Intestinal Protozoa Of Logan City And Vicinity, Robert B. Harrison May 1940

A Survey Of Human Intestinal Protozoa Of Logan City And Vicinity, Robert B. Harrison

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Parasitic protozoa of the intestinal tract of man were first observed by Anthony van Leeuwenhoek (1632-1723), a Dutch microscopist. In the year 1681, while observing his own excrement, Leeuwenhoek discovered and described certain forms of life which he called "animalcules" and which were verified later by workers in protozoology as Giardia lamblia, a protozoan parasite of the intestinal tract. During the period preceding the later part of the 19th century many observations of the parasitic intestinal protozoa of men and lower animals were made and many species were classified. It wasn't, however, until the year 1875 that a protozoan …


Utah State Agricultural College Graduates Now Living In Other States, Robert Dawson Simpson May 1940

Utah State Agricultural College Graduates Now Living In Other States, Robert Dawson Simpson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This is a study of graduates of the Utah State Agricultural College who have left Utah and are now residing elsewhere. Inquiries by faculty members and interested alumni, as well as the writer's own interest in the subject of migration, prompted the organization of this study.

The immediate reason for the inquiry was an enlarging interest on the campus concerning the present whereabouts of graduates who have left the state. When present residence was ascertained, other questions arose. What kind of employment had migrating graduates secured? What major interests were had? What important voluntary public services are graduates rendering to …


Comparison Of Various Types Of Milk Sampling Devices, William A. Hoskisson May 1940

Comparison Of Various Types Of Milk Sampling Devices, William A. Hoskisson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The importance of an accurate measurement of fat in milk deliveries is fully appreciated by most producers and plant operators. Since milk is purchased on a fat basis, the accuracy of the procedure used in sampling and testing the milk has often been questioned by both the buyer and seller.

A composite sample to be theoretically correct, should consist of aliquot portions of the milk shipments represented. Where aliquot portions are to be taken, a milk thief is commonly suggested. This device takes a vertical column of milk from the weigh tank. The idea is that the height of the …


The Relation Of Some Physical And Chemical Factors Of The Soil To The Productivity And Distribution Of Certain Waterfowl Food Plants At The Bear River Migratory Waterfowl Refuge, Grant Hortin Jensen May 1940

The Relation Of Some Physical And Chemical Factors Of The Soil To The Productivity And Distribution Of Certain Waterfowl Food Plants At The Bear River Migratory Waterfowl Refuge, Grant Hortin Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Within the last few years several areas within the state of Utah have been and are being developed for the conservation of migratory birds. Of utmost importance in this respect is the management of these areas so as to obtain a sufficient supply of rood plants for use by water fowl. Previous work done at the Bear River Migratory Waterfowl Refuge shows that the productivity of aquatic rood plants, chiefly Potamogeton pectinatus L. and Ruppia maritima L. varies with different localities and that these differences could not be attributed to chemical conditions of the water, i.e., dissolved oxygen, alkalinity, and …


Fifty-Fourth Annual Meeting Of The Iowa Academy Of Science And The Ninth Annual Convention Of The Junior Academy Of Science Of Iowa, April 19 And 20, 1940, Iowa Academy Of Science Apr 1940

Fifty-Fourth Annual Meeting Of The Iowa Academy Of Science And The Ninth Annual Convention Of The Junior Academy Of Science Of Iowa, April 19 And 20, 1940, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


Front Matter Apr 1940

Front Matter

Journal of the Minnesota Academy of Science

No abstract provided.


Regional Plankton Studies In Minnesota, Charles B. Reif Apr 1940

Regional Plankton Studies In Minnesota, Charles B. Reif

Journal of the Minnesota Academy of Science

No abstract provided.


Deer Inventory Studies In Minnesota, Gordon Fredine Apr 1940

Deer Inventory Studies In Minnesota, Gordon Fredine

Journal of the Minnesota Academy of Science

No abstract provided.


Further Studies On Prosthogonimus Macrorchis, Oviduct Fluke Of Poultry, With Special Reference To The Effect On Egg Production In The Ring-Necked Pheasant, Ralph W. Macy Apr 1940

Further Studies On Prosthogonimus Macrorchis, Oviduct Fluke Of Poultry, With Special Reference To The Effect On Egg Production In The Ring-Necked Pheasant, Ralph W. Macy

Journal of the Minnesota Academy of Science

No abstract provided.


Kentucky Warbler (Vol. 16, No. 2), Kentucky Library Research Collections Apr 1940

Kentucky Warbler (Vol. 16, No. 2), Kentucky Library Research Collections

The Kentucky Warbler

No abstract provided.


Block And Bridle Annual 1940 Apr 1940

Block And Bridle Annual 1940

Block and Bridle Annual (1933–2021)

The objectives of the Block and Bridle Club of Nebraska may be stated in a few words. They are, to foster an interest in the livestock industry, and to advertise that industry through favorable publicity; to prepare outstanding students of today for leadership tomorrow; to provide a means by which to congenial group of young men may meet and benefit each from the association of the others; and to participate in activities of the Campus so that the entire student body may profit not only in money but in useful things accomplished.


The Morphology And Histology Of The Virginia Oyster, Ostrea Virginica, Lister, Lewis Charles Goldstein Apr 1940

The Morphology And Histology Of The Virginia Oyster, Ostrea Virginica, Lister, Lewis Charles Goldstein

Master's Theses

The oyster has been known and used commercially since before the Roman and Greek civilizations, and reports of investigations pertaining to it can be found dating back almost to that period. Because of the commercial value of the oyster, most of the study of' the animal has dealt with its economic importance. Definite information concern­ ing the morphology and microscopic . structure of this Mollusc, therefore, is scarce. To be sure, there is an abundance of miscellaneous literature, but no systematic microscopic study has been reported. T. C . Nelson (1938) states, "A critical survey of the abundant and scattered …


Deterioration Of Midwestern Ranges, J. E. Weaver, F. W. Albertson Apr 1940

Deterioration Of Midwestern Ranges, J. E. Weaver, F. W. Albertson

Department of Agronomy and Horticulture: Faculty Publications

The native grasses of the mixed prairie and short-grass plains disclimax have been subjected for a long period of years to extreme drought, much overstocking, and severe damage from dust. Behavior of the vegetation during the dry year of 1933, the extreme drought of 1934, and the terrible dust storms and intermittent periods of desiccation during subsequent years, has been continuously observed (Weaver and Albertson, '36). Previous studies in this area furnished a back- ground which enabled one to compare present conditions with those of the pre-drought period (Weaver, '24; Clements and Weaver, '24; Albertson, '37). A large series of …


An Inquiry Into The Influence Of Environment On The Incidence Of Poultry Diseases, L. Van Es, J. F. Olney Mar 1940

An Inquiry Into The Influence Of Environment On The Incidence Of Poultry Diseases, L. Van Es, J. F. Olney

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The principal purpose of the investigation reported here was to evaluate, if possible, hygienic measures, and in addition to gather whatever information might become available pertaining to the relation of certain disorders to a given poultry population after its exposure to their specific etiologic factors. The experiments were conducted on a piece of ground upon which poultry had not been maintained for many years, if ever.


Vegetative Composition And Grazing Capacity Of A Typical Area Of Nebraska Sandhill Range Land, A. L. Frolik, W. O. Shepherd Mar 1940

Vegetative Composition And Grazing Capacity Of A Typical Area Of Nebraska Sandhill Range Land, A. L. Frolik, W. O. Shepherd

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The sandhill area of Nebraska occupies approximately 20,000 square miles of the central portion of the state. Being unadapted to cultivation, the land is for the most part still covered with native vegetation. It is utilized primarily for the production of livestock, chiefly cattle. During the period 1931 to 1938 the sandhills carried annually an average of 1,041,000 cattle, which amounted to 31 per cent of the total number in the state. The management practices used in the Nebraska sandhills have gained national recognition as a good example of range conservation in the United States. The purpose of this study …


Bulletin No. 291 - Range Resources Of Rich County, Utah, L. A. Stoddart Mar 1940

Bulletin No. 291 - Range Resources Of Rich County, Utah, L. A. Stoddart

UAES Bulletins

In 1936 the Utah Agricultural Experiment Station organized project 179 entitled "A study of agricultural resources of Utah and their utilization." The project was divided into four sub-projects, A dealing with agricultural economics, B dealing with soil resources, C dealing with irrigational water resources, and D dealing with range resources.

Sub-project D, entitled "Range resources and condition of vegetation cover," was begun in 1936 with a survey of Duchesne and Uintah Counties, and the findings were published as Utah Station Bulletin No. 283, "Range conditions in Uinta Basin, Utah." The field season of 1937 was devoted to Wasatch County, and …


A Study Of Subspecific Variation In The Yellow Pocket-Gopher (Geomys Lutescens) In Nebraska, And Of The Geographical And Ecological Distribution Of The Variants, Myron H. Swenk Feb 1940

A Study Of Subspecific Variation In The Yellow Pocket-Gopher (Geomys Lutescens) In Nebraska, And Of The Geographical And Ecological Distribution Of The Variants, Myron H. Swenk

University of Nebraska State Museum: Mammalogy Papers

The Yellow Pocket-Gopher (Geomys lutescens) was described by Merriam (14) in 1890, as a paler and smaller subspecies of Geomys bursarius, based on "numerous specimens received from the Sand Hills of western Nebraska", and especially upon an adult Cjl type specimen (No. 23595, U. S. N. M.) collected in the sandhills along Birdwood Creek, Lincoln County, Nebraska, May 27, 1889, by A. B. Baker. Although even as late as 1931 Scheffer (17) classified Geomys lutescens as a subspecies of G. bursarius, it is without doubt specifically distinct from G. bursarius. In all of its variations …


Kentucky Warbler (Vol. 16, No. 1), Kentucky Library Research Collections Jan 1940

Kentucky Warbler (Vol. 16, No. 1), Kentucky Library Research Collections

The Kentucky Warbler

No abstract provided.


Annual Report: 1940 Jan 1940

Annual Report: 1940

Cherry County (Nebraska) Extension: Historical Documents

The educational program of agricultural extension was conducted in Cherry County during 1940 by the Cherry County Extension Service. 329 families and business firms subscribed $1529.15 for support of the work. The county commissioners provided office quarters at a cost of $258.00 for the year. Other income provided $80.00 additional funds making a total operating fund of $1867.15.

Expenditures for the year were $255.00 for office quarters, heat and light, $89.60 finance committee expense, and $1824.14 for conducting the general program.

The program of work directed special emphasis to F-F-L, Beef Cattle, 4-H and Project club work.

Test plats of …


Farm Research In South Dakota: Fifty-Third Annual Station Report, July 1 1939 - June 30 1940, South Dakota State College Of Agriculture And Mechanic Arts Jan 1940

Farm Research In South Dakota: Fifty-Third Annual Station Report, July 1 1939 - June 30 1940, South Dakota State College Of Agriculture And Mechanic Arts

Agricultural Experiment Station and Research Farm Annual Reports

No abstract provided.


Index To Volume Viii Jan 1940

Index To Volume Viii

Nebraska Bird Review

Amundson, Geno A., article by, 19.

Avocet, 20, 21, 61, 78, 85, 86.

Baldpate, 5, 13, 16, 76, 84, 97, 104.

Bittern, American, 13, 50, 60, 76, 86, 87, 90, 104.

Blackbird, Brewer, 21, 81, 84, 94; Red-winged (subsp.), 5, 8, 12, 13, 16, 21, 31, 44, 53, 56, 58, 62, 81, 83, 84, 85, 86, 88, 94, 105; Rusty, 5, 28, 57, 81; Yellow-headed, 6, 17, 20, 21, 26, 57, 81, 86.

. . .

Wren, Common Rock, 62, 85; Eastern Carolina, 17; Western House, 6, 7, 8, 13, 16, 17, 19, 52, 57, 59, 79, 85, 86, 89, …


Nebraska Bird Review (January-June 1940) 8(1), Whole Issue Jan 1940

Nebraska Bird Review (January-June 1940) 8(1), Whole Issue

Nebraska Bird Review

Contents

The Relation of the Farm Shelterbelt to Wildlife. By Carroll F. Orendurff ................................................................ 1

General Notes ............................................................ 4

Distribution and Migration of the Chat in Nebraska and other Missouri Valley States. By Myron H. Swenk .................... 33