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

Digital Commons Network™

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

Physical Sciences and Mathematics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 901 - 924 of 924

Full-Text Articles in Entire DC Network

A Physical Hydrographic Study Of The Lafayette River, E. Glenn White Apr 1972

A Physical Hydrographic Study Of The Lafayette River, E. Glenn White

OES Theses and Dissertations

A basic investigation of the physical ~properties, temperature, density and current velocity, in the Lafayette River is presented. Graphs of the observations indicata a difference in salinity, density and current velocity- distributions after moderate to heavy rains from the graphs during a dry period. The changes in distribution indicate a change in the classification of the estuary from a type B/C, partially mixed estuary, to a type D, sectionally homogeneous estuary. The estuary is predominantly a well-mixed or sectionally homogeneous estuary.

Changes in salinity, temperature, density and current velocity over tidal cycles are discussed as well as tidal height data. …


Umr Journal: Alaska -- Its Mineral Potentials And Environmental Challenges, University Of Missouri--Rolla Jun 1971

Umr Journal: Alaska -- Its Mineral Potentials And Environmental Challenges, University Of Missouri--Rolla

UMR Journal -- V. H. McNutt Colloquium Series

No abstract provided.


Arctic Ecology: A Decade Of Experience, John F. Schindler Jun 1971

Arctic Ecology: A Decade Of Experience, John F. Schindler

UMR Journal -- V. H. McNutt Colloquium Series

A quick glance at the title of this presentation and the reader braces himself for another antipollution or “save-the-sod” type of discourse that has become so popular these days. I do not wish to detract from the importance or the need for such efforts but I would like to address myself to the the broader meaning of the term.

Ecology--the word comes from the Greek root “oikos” which means house or household. What I’d like to do is to tell you about this “house” I’ve been living in for the past 10 years.


Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation Jan 1971

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation

Publications (WR)

Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …


The Effects Of Indomethacin On A Strain Of Fibroblasts Cultivated In Vitro, John Thomas Mccloskey Jan 1971

The Effects Of Indomethacin On A Strain Of Fibroblasts Cultivated In Vitro, John Thomas Mccloskey

University of the Pacific Theses and Dissertations

Man has always searched for greater understanding of himself and his environment. As a result, much scientific investigation has been directed towards the understanding of the life process. In recent years, such scientific inquiry has become increasingly focused on the fundamental biochemical events taking place at the cellular, subcellular, and molecular levels. In the course of investigation into the nature of living things, research has often necessitated the development of new techniques and investigational tools to serve as experimental systems. Very often such new methods have made possible the discovery of previously unknown processes. One very interesting and useful investigational …


Studies On The Biology Of Oligochaetes From The Phreatic Water Of An Exposed Gravel Bed, Michael Ladle Jan 1971

Studies On The Biology Of Oligochaetes From The Phreatic Water Of An Exposed Gravel Bed, Michael Ladle

International Journal of Speleology

More than twenty species of oligochaeta belonging to the families Enchytraeidae, Naididae, Tubificidae and Lumbriculidae were found in the phreatic water of the river bank gravels. Psammoryctes barbatus, Rhyacodrilus coccineus and Styludrilus heringianus were found throughout the year, attaining maturity in the spring. These three species may be univoltine under these conditions. The family Naididae and a few species of Tubificidae show well marked seasons of abundance, chiefly in the summer and autumn.


An In Vivo Perfusion Apparatus For Studies On Gingival Disease In The Albino Rat : Assessment By A Perfusion Of The Enzymes Collagenase And Hyaluronidase, James A. Smith Jun 1970

An In Vivo Perfusion Apparatus For Studies On Gingival Disease In The Albino Rat : Assessment By A Perfusion Of The Enzymes Collagenase And Hyaluronidase, James A. Smith

Loma Linda University Electronic Theses, Dissertations & Projects

This thesis describes an in vivo perfusion apparatus which can continuously deliver controlled quantities of solutions to localized, contralateral intraoral areas in albino rats. Three animals were per fused on the experimental area (the mesial sulcular area of the maxillary first molar) on one side with tap water and Trypan blue. Localization of the solution delivered and minimal histological changes due to the presence of the apparatus was demonstrated on these animals. Solutions of .5%, 1%, and 2% hyaluronidase and collagenase were perfused on the experimental areas of nine animals. When both enzymes were used, hyaluronidase always preceded collagenase in …


Trace Metal Analysis Of Barren River And Nolin River Reservoirs By Atomic Absorption Spectroscopy, Mary Jo Kennedy Jul 1969

Trace Metal Analysis Of Barren River And Nolin River Reservoirs By Atomic Absorption Spectroscopy, Mary Jo Kennedy

Masters Theses & Specialist Projects

This research was part of a project underway at Barren River and Nolin River Reservoirs in south-central Kentucky. The research was partially supported by a grant through the Sport Fishing Institute, Washington, D.C.

The study reported herein was concerned with the analysis of trace metal concentrations in the two reservoirs. It is believed that the fish population may in part depend upon the trace metals present in the water. It is anticipated that the data presented in this paper will eventually be correlated with the biology studies of the reservoirs being carried out by the Department of Biology of Western …


Biological Studies Of Selected Reaches And Tributaries Of The Colorado River, Nelson Thomas, Federal Water Pollution Control Administration Oct 1968

Biological Studies Of Selected Reaches And Tributaries Of The Colorado River, Nelson Thomas, Federal Water Pollution Control Administration

Publications (WR)

This report fulfills the request of the Colorado River Basin Project, Denver, Colorado, to determine the effects of municipal and industrial wastes on the aquatic life in selected waters of the Colorado River Basin. These studies were conducted with the assistance of personnel from the Colorado River Basin Project.


Birds And Airports, Erwin W. Pearson Mar 1967

Birds And Airports, Erwin W. Pearson

Vertebrate Pest Conference Proceedings: 3rd (1967)

For all practical purposes, research in this country on the problem of bird hazards to aircraft began in 1960 with the crash of an Electra turboprop that carried 62 people to their deaths and was attributed to ingestion of starlings into the engines. In this paper I intend to review the problem and present some of the answers found by investigators in this country and, to lesser extent, abroad. The discussion will be roughly divided into two parts: 1) what: causes the problem, when, and where; and 2) what has been and is being done at airfields to reduce it. …


Ecological Control Of Bird Hazard To Aircraft, V. E. F. Solman Sep 1966

Ecological Control Of Bird Hazard To Aircraft, V. E. F. Solman

Bird Control Seminars Proceedings

The Canadian Wildlife Service has had twenty-five years experience with the problem caused by bird contacts with aircraft. I experienced my first bird strike, while flying as an observer on a waterfowl survey in August, 1940. Officers of the Service investigated bird problems at airports at Yarmouth, Nova Scotia, and Cartierville, Quebec, in the late 1940's. Those incidents involving gulls and low speed piston-engined aircraft caused minor damage to the aircraft but considerable disturbance to the operators. As aircraft speeds increased and airports became more numerous and busier the problem increased in extent and complexity. By 1960 it was apparent …


Diurnal Distribution Of Phytoplankton From A Single Station At The Mouth Of The James River, Harold G. Marshall Jan 1966

Diurnal Distribution Of Phytoplankton From A Single Station At The Mouth Of The James River, Harold G. Marshall

Biological Sciences Faculty Publications

Eight sets of water samples were taken to a depth of 36 ft. during a 24-hr. period. A homogeneity was found in the vertical distribution of the total phytoplankton in samples from 7 of the 8 hydro-casts. Skeletonema costatum and Asterionella japonica were the most numerous phytoplankters in every sample, with the majority of their counts each exceeding 500, 000 cells per liter.


The Distribution Of Phytoplankton Along A 140 Mile Transect In The Chesapeake Bay, Harold G. Marshall Jan 1965

The Distribution Of Phytoplankton Along A 140 Mile Transect In The Chesapeake Bay, Harold G. Marshall

Biological Sciences Faculty Publications

The composition of phytoplankton progressively changed in the surface samples taken between Norfolk, Virginia and Cambridge, Maryland. These was an inverse relationship between the numbers of phytoplankters and zooplankters in the transect samples. Vertical stratification of the plankton was studied at two 24-hr, stations at the Great Wicomlco and Patuxent Rivers. The vertical centers of zooplankton and phytoplankton populations fluctuated over the study period and evidence is given to support a grazing phenomenon. Large concentrations of nannoplankters were found in all the plankton samples taken and is attributed to the collection procedure using the Van Dorn sampler.


A Review Of The Mites Of The Family Pseudocheylidae Oudemans, 1909 (Acarina, Prostigmata), Edward W. Baker, Warren T. Atyeo Jan 1964

A Review Of The Mites Of The Family Pseudocheylidae Oudemans, 1909 (Acarina, Prostigmata), Edward W. Baker, Warren T. Atyeo

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

Four genera and ten species are included; these are: Pseudocheylus biscalattts Ber1ese, 1888, P. americanus (Ewing), 1909, Stigmocheylus brevisetus Berlese, 1910, Anoplocheylus europaeus (Berlese), 1910, A. clavatus, n. sp., A. aegypticus, n. sp., A. protea (Womersley), 1935, Neocheylus natalensis Tragardh, 1906, N. nidcolus Lawrence, 1954, and N. collis, n. sp.


The Nebraska Sandhill Lakes: Their Characteristics And Fisheries Management Problems, D. B. Mccarraher Jan 1960

The Nebraska Sandhill Lakes: Their Characteristics And Fisheries Management Problems, D. B. Mccarraher

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

A brief look at the map of Nebraska will readily point out the obvious fact that the sandhills comprise a considerable portion of the land area of the state. To be more precise, an area encompassing around 20,000 square miles or about one quarter of the total state area. This is indeed a vast prairie region long noted for its fine cattle and native hay crops. It is a region of vegetative dune sandhills, sandy basins and valleys, exposed ground water, spring seep lakes and marshes. Since much is already known concerning the land portion of the sandhills it is …


Biological Indices Of Water Pollution, With Special Reference To Fish Populations, Peter Doudoroff, Charles E. Warren Jan 1957

Biological Indices Of Water Pollution, With Special Reference To Fish Populations, Peter Doudoroff, Charles E. Warren

Other Publications in Wildlife Management

A number of investigators have very recently published discussions having to do with biological indices and biological measures of water pollution (1) (2) (7) (13) (14) (15) (16) (26) (27) (28) (29) (30) (36) (38). Fjerdingstad (12) has discussed some of the pertinent European literature. The fundamental concepts presented by these authors are not original, for the idea that aquatic organisms can be useful "indicators" of environmental conditions, and particularly of the degree of pollution of water with organic wastes, has a long history (12). Because of certain novel features and the relatively wide scope of the studies, and the …


The Value Of Including Chemistry Content In The Study Of High School Biology, Ramon Duane Buckley Jan 1957

The Value Of Including Chemistry Content In The Study Of High School Biology, Ramon Duane Buckley

Dissertations and Theses @ UNI

The purpose was to evaluate the effect of including some definite chemistry content in high school biology. This evaluation was made by comparing outcomes of instruction in two different groups of a high school biology course. The two groups were equated in terms of the intelligence quotients, the sex, and the previous achievement in biology of the class members. The comparative gains in factual knowledge were measured by means of an evaluation test. The comparative gains in appreciations and interests in biology were measured with a questionnaire.


Stream Pollution- Aquatic Macro-Invertebrate Communities As Indicators Of Organic Pollution In Lytle Creek, Arden R. Gaufin, Clarence M. Tarzwell Jul 1956

Stream Pollution- Aquatic Macro-Invertebrate Communities As Indicators Of Organic Pollution In Lytle Creek, Arden R. Gaufin, Clarence M. Tarzwell

United States Environmental Protection Agency: Publications

Year-round field studies of the com position and ecology of stream communities associated with the purification of organic wastes in streams were initiated on Lytle Creek in October, 1949. This creek, which is located about 45 miles northeast of Cincinnati, Ohio, is a tributary of the Little Miami River. Its drainage basin comprises 27 sq. mi., a third of which is contained within the city limits of Wilmington, Ohio, a city of some 7,412 persons


Report Of The State Geologist 1947-1948, Maine Geological Survey Mar 1949

Report Of The State Geologist 1947-1948, Maine Geological Survey

Maine Collection

Report of the State Geologist 1947-1948.

Maine Geological Survey - Maine Development Commission, Augusta, Maine - March 1949.

Contents: Activity of the Maine Geological Survey, 1947-48 / Joseph M. Trefethen -- Review of the Aroostook County Manganese Deposits / Joseph M. Trefethen -- Notes on Ground Water Conditions in Maine / Joseph M. Trefethen -- The Desert of Maine / Henry Allen and Elbert Pratt -- Reconnaissance Surveys of Limestones in Franklin County, Maine / Lawrence Wing and Arthur Dawson -- Preliminary Report on Asbestos and Associated Rocks of Northwestern Maine / Lawrence Goldthwait -- Clay Survey 1948 / Earl …


Abstract Papers Apr 1942

Abstract Papers

Journal of the Minnesota Academy of Science

No abstract provided.


Front Matter Apr 1941

Front Matter

Journal of the Minnesota Academy of Science

No abstract provided.


The Search For Natural History Areas In Minnesota, A. N. Wilcox, W. J. Breckenridge, R. L. Donovan, T. B. Magath, H. E. Stork, Gustav Swanson Apr 1938

The Search For Natural History Areas In Minnesota, A. N. Wilcox, W. J. Breckenridge, R. L. Donovan, T. B. Magath, H. E. Stork, Gustav Swanson

Journal of the Minnesota Academy of Science

No abstract provided.


A Chemical And Biological Study Of The Waters Of Elephant Butte Reservoir As Related To Fish Culture, John Greenbank Jun 1937

A Chemical And Biological Study Of The Waters Of Elephant Butte Reservoir As Related To Fish Culture, John Greenbank

Chemistry and Chemical Biology ETDs

The investigation of fresh-water lakes with respect to fish and other aquatic life had its beginning in Europe in the latter half of the nineteenth century. Probably the only man who may be considered to be the founder of the science of limnology was F. A. Forel, of the University of Lausanne Switzerland. Professor Forel’s work was the start of a rapidly developing branch of study, not only in Europe, but also presently in North America.


Droughts, Dust Storms And Desolation, D. H. Davis Jan 1937

Droughts, Dust Storms And Desolation, D. H. Davis

Journal of the Minnesota Academy of Science

No abstract provided.