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Seasonal Variation In The Tubular And Interstitial Areas Of The Testes In Sternotherus Odoratus L., Robert Hans Spaet Jan 1973

Seasonal Variation In The Tubular And Interstitial Areas Of The Testes In Sternotherus Odoratus L., Robert Hans Spaet

Masters Theses

Seasonal changes within the tubular and interstitial areas of the testes in Sternotherus odoratus are investigated, histologically and histochemically. Forty specimens were collected in Illinois, Tennessee and Louisiana between May, 1969 and August, 1972.

Many of the histological and macroscopic observations made by Risley (1938) on the spermatogenic cycle of S. odoratus in Michigan are confirmed. Contrary to his findings, fluctuations in interstitial cell nuclear diameters are observed during spermatogenesis. Greatest diameters coincide with what Risley has considered " . . . period of most active breeding." Sertoli cell nuclear diameters undergo similar fluctuations being greatest during spring breeding and …


Morphometric Variation In Aphelenchus Avenae Bastian, 1865 With Varied Nutrition And Time, John P. Kline Jan 1973

Morphometric Variation In Aphelenchus Avenae Bastian, 1865 With Varied Nutrition And Time, John P. Kline

Masters Theses

The effect of varied time, nutritional media, and species of fungus on taxonomic characters (L, a, b1, c, and V) of Aphelenchus avenae was investigated. The effect of these ecological conditions on morphometrics was variable; however, these characters varied significantly with increased time, decreased nutritional media, and species of fungus. The greatest number of morphometric changes occurred with increased time, and the fewest with species of fungus. With changing environmental conditions, “V” values were the most stable character.


Nutritional Components Of The Standing Plankton Crop In Mississippi Sound, Mohammed Saeed Mulkana, Walter Abbott Jan 1973

Nutritional Components Of The Standing Plankton Crop In Mississippi Sound, Mohammed Saeed Mulkana, Walter Abbott

Gulf and Caribbean Research

A study on seasonal changes in the nutritional components of standing plankton biomass was made from 20 April 1965 to 6 September 1966. Plankton were separated into net plankton and nannoplankton fractions. Nannoplankton3 standing biomass exceeded by 72 times that of net plankton.

Although protein and carbohydrate levels were higher in net plankton on a unit weight basis, total nutrients available from nannoplankton were substantially higher. Some seasonal trends were apparent as changes in the standing biomass in net plankton. Nannoplankton exhibited no seasonal trends. Lipid and caloric values of net plankton showed seasonal trends similar to those shown by …


The Predatory Behavior Of Pisaster Ochraceus (Brandt), David A. Jillson Jan 1973

The Predatory Behavior Of Pisaster Ochraceus (Brandt), David A. Jillson

University of the Pacific Theses and Dissertations

The persistence of predator-prey systems in evolutionar time is a function of the efficiency with which the predator obtains its food, and the ability of the prey to avoid ex- tinction. One of the important components of survival of the system is environmental heterogeneity (Huffaker 1958).

Along rocky intertidal regions of the northern Pacific coast of North America, a major predator, the starfish Pisast ochraceus has a dominant effect upon patterns of distribution of many intertidal organisms (Paine 1966). Likewise, the distribution of intertidal fauna exert an effect upon the activities of Pisaster. Other biological interactions such an grazing activities …


Larval Development And Life History Of Phyllaplysia Taylori Dall (Opistobranchiata: Anaspidea), Cecilia Blackwell Bridges Jan 1973

Larval Development And Life History Of Phyllaplysia Taylori Dall (Opistobranchiata: Anaspidea), Cecilia Blackwell Bridges

University of the Pacific Theses and Dissertations

Taxonomic studies involving only adult forms of organisms may not necessarily provide complete information about differentiation of species or about the evolutionary relationships between species grouped in higher taxa. The taxonomic importance of embryonic or larval morphology has been limited only by the lack of detailed comparative morphological work on development. Fretter (1967) has shown that larval shell characteristics are reliable for taxonomic identification of some British prosobranchs. Ostergaard (1950) proposed using the structure of egg masses, larval shell type and developmental characteristics to confirm adult taxonomic position. In recent literature reviews of the larval biology of opisthobranch, it has …


Tissue Culture Of Camptotheca Acuminata Decaisne (Nyssaceae), Ron Charles Cooke Jan 1973

Tissue Culture Of Camptotheca Acuminata Decaisne (Nyssaceae), Ron Charles Cooke

University of the Pacific Theses and Dissertations

Camptotheca acuminata Decaisne (Nyssaceae) is endemic to China. The plant was brought to the United States only on a few occasions and thus can be considered rare in this country. A search of the plant kingdom for species that produced anticancer substances revealed that ethanolic extracts of Camptotheca acuminata had such a property. The active constituent was identified eventually. Further testing and possible marketing of the active principle, and alkaloid, (camptothecin) depended on a combination of factors: obtaining the plant from China, organization of a mass planting program in the United States or chemical synthesis of the drug.

Due to …


Some Aspects Of Mercury Accumulation By The Purple Shore Crab Hemigrapsus Nudus Dana (Crustacea: Decapoda), Ralph Gene Swanson Jan 1973

Some Aspects Of Mercury Accumulation By The Purple Shore Crab Hemigrapsus Nudus Dana (Crustacea: Decapoda), Ralph Gene Swanson

University of the Pacific Theses and Dissertations

The present study has attempted to investigate some of the more basic questions concerning the toxicity and accumulation of mercury in the purple shore crab, Hemigrapsus nudus. This rocky intertidal denizen is found in abundance along the entire Pacific coast of the United States from Sitka, Alaska, to the Gulf of California where it dominates the mid-tide pool region. Local specimens were collected just north of the Pacific Marine Stations, Dillon Beach, Marin County, California. The animal is hearty and can be kept in a state of good health for long periods of time in the laboratory with minimum care …


Models Of Primary Productivity In The Oceans, William Yi-Been Chang Jan 1973

Models Of Primary Productivity In The Oceans, William Yi-Been Chang

University of the Pacific Theses and Dissertations

A general mathematical equation relating variables affecting primary production has been developed to predict changes .in the vertical distribution of primary production in the oceans. The model is tested and shown to fit empirical observations from diverse oceanic areas.


Studies Of The Effects Of Solvent Composition On The Association-Dissociation Of Oxyhemerythrin As Determined By Analytical Gel Chromatography, Kim Hock Tan Jan 1973

Studies Of The Effects Of Solvent Composition On The Association-Dissociation Of Oxyhemerythrin As Determined By Analytical Gel Chromatography, Kim Hock Tan

Dissertations

No abstract provided.


The Dietary Intake Of Preschool Children Attending The Public Health Clinics In San Bernardino, California, Glendover V. Brown Jan 1973

The Dietary Intake Of Preschool Children Attending The Public Health Clinics In San Bernardino, California, Glendover V. Brown

Loma Linda University Electronic Theses, Dissertations & Projects

Preschool children attending Well Baby Clinics directed by the Public Health Department of San Bernardino, California, were the sub jects in this study. The purpose of the study was (1) to compare the eating pattern and habits of the preschool children attending the San Bernardino Public Health Clinics, (2) to assess any differences in the dietary intake of the three major ethnic groups, namely, Mexican- Americans, Whites, and Blacks, and (3) to determine the adequacy of the dietary intake of the preschool children attending the San Bernardino Clinics. One hundred and seventy-seven subjects in this study included 51 Mexican-Americans, 74 …


Agricultural Experiment Station News December 1972 Dec 1972

Agricultural Experiment Station News December 1972

Agricultural Research Division: News and Annual Reports

CONTENTS:
FROM THE DIRECTOR'S OFFICE
ARS ORGANIZATION
PERSONNEL ACTIONS
GRANTS AND CONTRACTS
GENERAL NOTES
AGRICULTURAL EXPERIMENT STATION PUBLICATIONS – NOVEMBER 1972
ABSTRACTS
BULLETINS PRINTED


Southeast South Dakota Experiment Farm Annual Progress Report, 1972, Agricultural Experiment Station Dec 1972

Southeast South Dakota Experiment Farm Annual Progress Report, 1972, Agricultural Experiment Station

Agricultural Experiment Station and Research Farm Annual Reports

Research Manager’s Report: The 1972 year found the Experiment Farm and Research and Extension Center with the usual variety of programs and activities. Several personnel changes were made with Jake Fredrikson, Superintendent moving to Brookings to take a position in the Veterinary Science Department. Burton Lawrensen was made Agronomist and continues to work with crops research. Vacancies filled in classified personnel staff have added new talents to the farm work crew. A number of research studies were initiated this year. New projects in Plant Science included the following titles: Potash on Grain Sorghum, Chisel Plow Experiment, No-till Planting of Corn …


The Recovery Of Portage Creek In Vicksburg, Michigan, Michael Henry Herbert Dec 1972

The Recovery Of Portage Creek In Vicksburg, Michigan, Michael Henry Herbert

Masters Theses

No abstract provided.


Cost Of Producing Beef With Different Types And Weights Of Cattle, Danny G. Fox Oct 1972

Cost Of Producing Beef With Different Types And Weights Of Cattle, Danny G. Fox

South Dakota Cattle Feeders Field Day Proceedings and Research Reports, 1972

Currently, there is much interest in changing the U.S.D.A. grading standards. Some suggest that we completely eliminate the use of them. There are many reasons for this, but the major one is that many feel that the present system does not always correctly identify the most desirable carcasses. Many cattle now come to market at 15 to 18 months of age and are not marbled because of their youthfulness.


Sixteenth Annual Cattle Feeders Day, Animal Science Department Oct 1972

Sixteenth Annual Cattle Feeders Day, Animal Science Department

South Dakota Cattle Feeders Field Day Proceedings and Research Reports, 1972

These are the complete proceedings of the sixteenth annual Cattle Feeders Day held on October 27, 1972 at South Dakota State University.


Effect Of Nutrition On The Carcass Composition And Quality Of Cattle, R. L. Preston Oct 1972

Effect Of Nutrition On The Carcass Composition And Quality Of Cattle, R. L. Preston

South Dakota Cattle Feeders Field Day Proceedings and Research Reports, 1972

Beef is a highly desirable food, both nutritionally and for the pleasure it gives during its consumption. Protein of high quality is the major nutritional asset of beef, as well as supplying certain minerals and vitamins. As important as this role is, it is not the main reason that beef is the most desired of all meats. Beef is consumed because it provides great satisfaction. What then contributes of this satisfaction?


Agricultural Experiment Station News October 1972 Oct 1972

Agricultural Experiment Station News October 1972

Agricultural Research Division: News and Annual Reports

CONTENTS:
FROM THE ACTING DIRECTOR'S DESK
PERSONNEL ACTIONS
GRANTS AND CONTRACTS
GENERAL NOTES
AGRICULTURAL EXPERIMENT STATION PUBLICATIONS - September 1972
BULLETINS PRINTED
ABSTRACTS


Effects Of The Exogenous Hormone Cortisone Acetate On Drosophila Virilis Larvae, Margarita Midelfort Oct 1972

Effects Of The Exogenous Hormone Cortisone Acetate On Drosophila Virilis Larvae, Margarita Midelfort

Bachelors’ Theses

Recent experiments published in the literature have questioned the importance of the appearance of chromosomal puffs during larval development in Dipterans since Sciara larvae fed the vertebrate hormone cortisone apparently show no puffs without impairment of normal development. We have used Drosophila virilis larvae to test these results because distinct morphological criteria can be used to assess the developmental age of third instar larvae and predict the appearance of a specific puff. We have found that even though ingestion of cortisone acetate by D. virilis larvae causes a marked delay in their development the chromosome puffs appear at the expected …


Winter Wheat Cultivar Performance In An International Array Of Environments, J. E. Stroike, V. A. Johnson Oct 1972

Winter Wheat Cultivar Performance In An International Array Of Environments, J. E. Stroike, V. A. Johnson

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The International Winter Wheat Performance Nursery organized in 1968 by the Nebraska Agricultural Experiment Station in cooperation with the Agricultural Research Service, U.S. Department of Agriculture, under a contract with the Agency for International Development, U.S. Department of State, has presented a unique opportunity to measure the performance and stability of 28 winter wheat cultivars over an international array of environments. Computations of three parameters for yield, selected agronomic traits, and grain protein and lysine were made from nursery data recorded in 1969 and 1970.


Phytoplankton Successions And Lake Dynamics In Las Vegas Bay, Lake Mead, Nevada, Ervon R. Koening, Richard W. Tew, James E. Deacon Oct 1972

Phytoplankton Successions And Lake Dynamics In Las Vegas Bay, Lake Mead, Nevada, Ervon R. Koening, Richard W. Tew, James E. Deacon

Publications (WR)

Phytoplankton successions, applications of the general growth equation, and physical measurements have been employed to investigate events occurring at the interface between industrial and sewage effluent contained in Las Vegas Wash and the waters of Lake Mead, Nevada. The data indicate that the entering waters tend to form a density current interrupted at intervals by dynamic effects generated in the lake. The dynamic relationships described here for the spring months suggest that a much more thorough understanding of physical, chemical and biological interactions is necessary to permit solution of the numerous problems of Las Vegas Bay discussed or alluded to …


Agricultural Experiment Station News September 1972 Sep 1972

Agricultural Experiment Station News September 1972

Agricultural Research Division: News and Annual Reports

CONTENTS:
FROM THE DIRECTORS OFFICE
NEW ACCOUNT NUMBERING SYSTEM
PERSONNEL ACTIONS
GRANTS AND CONTRACTS
GENERAL NOTES
AGRICULTURAL EXPERIMENT STATION PUBLICATIONS – August 1972
ABSTRACTS


Agricultural Experiment Station News August 1972 Aug 1972

Agricultural Experiment Station News August 1972

Agricultural Research Division: News and Annual Reports

CONTENTS:
FROM THE DIRECTOR'S OFFICE
PERSONNEL ACTIONS
GRANTS AND CONTRACTS
GENERAL NOTES
ALOHA
NEBRASKA AGRICULTURAL EXPERIMENT STATION PUBLICATIONS - July 1972
ABSTRACTS


The Effects Of Different Gases On Excystation Of Coccidian Oocysts, James B. Jensen Aug 1972

The Effects Of Different Gases On Excystation Of Coccidian Oocysts, James B. Jensen

Theses and Dissertations

Excystation of coccidian oocysts is a diphasic process where CO2 and suitable reducing agents cause changes in oocyst wall permeability (phase I) allowing the entrance of trypsin and bile which activate the sporozoites (phase II). This project was an indirect study of the mechanism of CO2 action by the substitution of NO, NO2, N2O, H2S, SO2 , CH4, NH3 and 8M urea in place of CO2. Changes in oocyst wall permeability of Eimeria stiedae, E. bovis and E. tenella were determined by incubation with the reagents and cysteine HCl followed by treatment with trypsin and bile to initiate activation of …


Effects Of Dietary Factors And Morphine Administration On Voluntary Alcohol Consumption And Dopamine Metabolism In Rats, Claudia Smithson Aug 1972

Effects Of Dietary Factors And Morphine Administration On Voluntary Alcohol Consumption And Dopamine Metabolism In Rats, Claudia Smithson

Loma Linda University Electronic Theses, Dissertations & Projects

The effect of diet and dietary additives on voluntary alcohol consumption in male Sprague-Dawley rats was studied. Alcohol intake measured weekly and reported as ml of a 10% solution ingested per 100 grams body weight. A four week pre-experimental period was designed to determine individual tendencies to drink and thus to eliminate the high and low drinkers from the study. No difference was found in alcohol intake with either starch or sugar as the carbohydrate source; however, there was a greater weight gain ( p < .025) in those animals consuming sugar-based diets. Rats on poor-quality diets containing minimal amounts of vitamins and minerals continued to gradually increase alcohol consumption during the study. This diet, supplemented with coffee, caused the greatest significant increase in alcohol intake and the lowest weight gains. Addition of coffee to the diets significantly increased alcohol consumption (p< .005) but decreased growth rate (p < .0005) . However, when the poor quality diets were supplemented with vitamins and minerals, alcohol consumption was reduced by about 50% (p < .005) and weight gain was significantly increased (p < .0005).

The daily intraperitoneal administration of morphine sulfate significantly decreased alcohol intake (p < .02) and the per cent of total fluid consumed as alcohol (p < .02) but did not effect water consumption.

An attempt was …


Bionomics And The Influence Of Diet Upon The Maturation Of Orchopeas Leucopus (Baker), Lynden Phillip Baum Aug 1972

Bionomics And The Influence Of Diet Upon The Maturation Of Orchopeas Leucopus (Baker), Lynden Phillip Baum

Theses and Dissertations

Knowledge of the bionomics of plague vectors, es-pecially factors which influence life history, host pre-ference, and fluctuations of flea populations, are basic to an understanding of plague ecology. Orchopeas leucopus (Baker), an ectoparasite of cricetid rodents such as Peromyscus maniculatus (Wagner), and Peromyscus truei (Baird), is a vector of plague in the western United States (Holdenried and Morlan, 1955). In a study of nine biotic corrnnunities in the Utah portion of the Great Basin, P. maniculatus was the most abundant rodent in seven of the biotic corrnnunities (Olsen, 1966). Because of the ubiquitous nature of P. maniculatus an interchange of …


Population Dynamics Of Fleas (Siphonaptera) On The Uinta Ground Squirrel, Spermophilus Armatus Kennicott, Dennis I. Anderson Aug 1972

Population Dynamics Of Fleas (Siphonaptera) On The Uinta Ground Squirrel, Spermophilus Armatus Kennicott, Dennis I. Anderson

Theses and Dissertations

The Uninta ground squirrel, Spermophilus armatus Kennicott, is the most abundant diurnal rodent in the Wasatch Mountains at the 7,000-9,000 foot level particularly in the campgrounds and picnic areas. Contact between man and the Uninta ground squirrel may be hazardous inasmuch as the causative agent of plague has been isolated from S. armatus and its flea parasites (Public Health Reports, 1937, 1938a, 1938b; Meyer, 1938; Byington, 1940; Allred, 1951; and Beck, 1955). Since these fleas are vectors of sylvatic plague and potential vectors of human plague, detailed knowledge about their population dynamics is desirable.


The Distribution Of Meyenia Fluviatilis At Lincoln Beach Area Of Utah Lake With Notes On Seasonal Occurrence Of Gemmules, Chadwick E. Smith Aug 1972

The Distribution Of Meyenia Fluviatilis At Lincoln Beach Area Of Utah Lake With Notes On Seasonal Occurrence Of Gemmules, Chadwick E. Smith

Theses and Dissertations

This study of the distribution of the fresh-water sponge, Meyenia fluviatilis, at the Lincoln Beach area of Utah Lake involved the following: First, sampling of the area for the presence or absence of the species. Second, sampling at two separate areas at different depth intervals to determine if the number of sponge colonies and colony size were in any way related to depth. Finally, monthly sampling at one area to determine when gemmules of M. fluviatilis were present in the sponge colonies. Meyenia fluviatilis was found to be commonly distributed in 1-2 m of water on the lower surface of …


The Interaction Of Promazine With Selected Macromolecules And A Membrane Utilizing Absorption And Emission Spectroscopy, Jess D. Keeler Aug 1972

The Interaction Of Promazine With Selected Macromolecules And A Membrane Utilizing Absorption And Emission Spectroscopy, Jess D. Keeler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The association of promazine-HCl with bovine serum albumin, ammonium detergent micelles, and hemoglobin-free-rabbit-erythrocyte membranes were measured using the changes in the absorption and the emission of the interactants plus the fluorescent probe 1-anilino-8-naphthalene sulfonate. The binding of a promazine to serum protein and membrane did not alter the emission of the drug. However, the binding did produce a measurable quenching of the membrane and protein fluorescence. The quenching reaction was pH sensitive for both the protein and the membrane. Promazine binding to serum protein produced a hyperchromic change in the drugs absorption spectrum which paralleled the quenching reaction. The binding …


A Revision Of The Genus Sphaeralcea (Malvaceae) For The State Of Utah, Jane Ardis Murray Jefferies Aug 1972

A Revision Of The Genus Sphaeralcea (Malvaceae) For The State Of Utah, Jane Ardis Murray Jefferies

Theses and Dissertations

It is the attempt of the present writer to present a concise picture of the genus Sphaeralcea as it occurs in the state. Descriptions, a specific key, distribution maps, illustrations and pertinent synonomy are presented.


The Effects Of Temperatures And Chemicals On The Oocysts Of Eimeria Stiedae, Charles Larry Keehner Jul 1972

The Effects Of Temperatures And Chemicals On The Oocysts Of Eimeria Stiedae, Charles Larry Keehner

Theses and Dissertations

A study was made of the effects of temperatures and chemicals on the unsporulated and sporulated oocysts of Eimeria stiedae. In general, oocysts were affected by temperatures lower than -10 C and above +39 C, while normal development occurred between these temperatures. Unsporulated oocysts were more tolerant to temperature extremes, as they survived up to 8 days at 39 C and 12 days at -28 C. Sporulated oocysts were killed after 24 hours storage at 39 C and 4 days at -28 C. Oocyst resistance to low temperatures was not improved if unsporulated and sporulated oocysts were conditioned before and …