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Biology

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Articles 1891 - 1920 of 2280

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Mitotic Triggers In The Cell Cycle: Phase Dependency Of Cleavage Advance On The Chromosome Cycle In Parthenogenetically Activated Sea Urchin Eggs., Barbara Ellen Wolfanger Belisle Jan 1981

Mitotic Triggers In The Cell Cycle: Phase Dependency Of Cleavage Advance On The Chromosome Cycle In Parthenogenetically Activated Sea Urchin Eggs., Barbara Ellen Wolfanger Belisle

LSU Historical Dissertations and Theses

In the sea urchin egg, metabolic activation, DNA synthesis and the chromosome cycle can be induced with parthenogenic activators (NH(,4)Cl or procaine) although no spontaneous cleavage will occur. To determine the effects of these agents on other cell cycle events, eggs from four species of sea urchins were activated with NH(,4)Cl or procaine and then fertilized at different times of the chromosome cycle. These eggs show a decrease in the time to first cleavage which is apparently coupled to the parthenogenecally induced chromosome cycle. The advance is seen whether the activated eggs are fertilized during the first or second chromosome …

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Ethyl Methanesulfonate (Ems) And Diethylnitrosamine (Den) Effect On Germ Cells Of Drosophila Melanogaster., Haimei Huang Jan 1981

Ethyl Methanesulfonate (Ems) And Diethylnitrosamine (Den) Effect On Germ Cells Of Drosophila Melanogaster., Haimei Huang

LSU Historical Dissertations and Theses

With autoradiography and fluorescent stain techniques, the degree of ethylation of Drosophila melanogaster sperm following treatment with (1-('3)H)-ethyl-methanesulfonate (EMS) or (2-('3)H)-diethylnitrosamine (DEN) was shown by different levels of silver grains on sperm. The degree of ethylation of sperm cells treated with the mutagen in different germ cell stages of development (sperm, spermatids, spermatocytes, or spermatogonia) was determined by varying the time of sampling. The average grains per sperm head from different samples were computed and analyzed with SAS program by the IBM 3033 computer at System Network Computer Center on the LSU campus in Baton Rouge. The sperm which originated …

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Objectives Of Animal Use In Biology Courses, William V. Mayer Jan 1980

Objectives Of Animal Use In Biology Courses, William V. Mayer

Education Collection

To confine discussion of educational use of animals to experimentation is to focus on only part of the animal use problem. To focus on use of animals in the classroom solely is to negate the value of field and community resource areas such as zoos, animal parks, nature trails, etc. The primary objective in dealing with living organisms is to inculcate a respect for all life. Objectives that focus on use of living animals for experimental purposes can, at best, be secondary and may in many cases be contrived. An understanding of animal life requirements and animal contributions is an …

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No Pain Infliction By Untrained Youths, Christine Stevens Jan 1980

No Pain Infliction By Untrained Youths, Christine Stevens

Education Collection

Outlined are the efforts of the Animal Welfare Institute (AWl) for the last twenty-five years to end abuses to animals in high school biology programs. After concluding that the AWl's two brief rules prohibiting painful experimentation were not well understood by students even after years of effort, the AWl adopted the rules of the Canadian science fairs, which are similar to the Westinghouse Talent Search in that they simply prohibit experimentation on vertebrate animals. The presentation includes reference to the AWI manual, "Humane Biology Projects."

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Humaneness Supersedes Curiosity, F. Barbara Orlans Jan 1980

Humaneness Supersedes Curiosity, F. Barbara Orlans

Education Collection

Ethical considerations need to be addressed with respect to educational use of animals. Society extends greater latitude in what is permissible to do to an animal in the name of science to a professional research worker than to a high school student. A balance needs to be made of the significance of the expected experimental results, on the one hand, which the ethical costs, (in terms of pain or death to the animal), on the other. A reasonable boundary can be drawn, based on ethical as well as on practical considerations, to exclude invasive procedures on vertebrate animals in high …

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Ameson Michaelis (Microsporida) In The Blue Crab, Callinectes Sapidus: Altered Host Cell And Isolated Parasite Metabolism., Anna Marie Carmela Findley Jan 1980

Ameson Michaelis (Microsporida) In The Blue Crab, Callinectes Sapidus: Altered Host Cell And Isolated Parasite Metabolism., Anna Marie Carmela Findley

LSU Historical Dissertations and Theses

The Microsporida are a large group of highly specialized obligate intracellular protozoan parasites. Despite their wide distribution in nature and their devastating effect on a variety of animal populations, relatively little is known about the physiological characteristics of these parasites.

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The Occurrence Of Alliinase In Selected Bacterial Strains., Lawrence A. Reily Jan 1980

The Occurrence Of Alliinase In Selected Bacterial Strains., Lawrence A. Reily

LSU Historical Dissertations and Theses

Alliinases have been studied in animals and plants, but relatively little attention has been given to bacterial alliinases. Therefore, an investigation was initiated to determine the prevalence and nature of alliinase systems in bacteria. A method of determining alliinase activity in bacteria was developed. The procedure was based on qualitative or quantitative detection of allicin, by a color reaction with N-ethylmaleimide. Alliinase was found to be present in some strains and absent in others. In still other strains, alliinase seemed to be a variable characteristic. It was speculated that alliin cleavage in bacteria might be accomplished via an inducible cystathionase. …

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Studies On The Physiology Of A Cellulolytic Strain Of Aspergillus Terreus Under Conditions Of Batch And Continuous Cultivation., Thomas Ferrell Miller Jan 1980

Studies On The Physiology Of A Cellulolytic Strain Of Aspergillus Terreus Under Conditions Of Batch And Continuous Cultivation., Thomas Ferrell Miller

LSU Historical Dissertations and Theses

Experiments have been conducted to determine the feasibility of the bioconversion of cellulose into Single Cell Protein (SCP) using a thermotolerant, cellulolytic strain of Aspergillus terreus. Crude cellulases produced during the growth of fungal biomass were tested for their ability to generate glucose syrups by enzymatic hydrolysis of cellulose. Studies on continuous cultivation of glucose-limited A. terreus resulted in the development of a highly optimized medium which allowed the organism to achieve similar maximum specific growth rates (umax) measured in batch culture. Upon proportionate increase of the medium composition, there was no decrease in growth rates or in biomass yields …

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Classification And Phylogeny In The Suborder Euplotina (Ciliophora, Hypotrichida), Bruce Fleming Hill Jan 1980

Classification And Phylogeny In The Suborder Euplotina (Ciliophora, Hypotrichida), Bruce Fleming Hill

Doctoral Dissertations

No abstract provided.

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Metabolic Characteristics And Susceptibility To Laminitis In Morgan And Thoroughbred Horses, Colette Helene Janson Jan 1980

Metabolic Characteristics And Susceptibility To Laminitis In Morgan And Thoroughbred Horses, Colette Helene Janson

Doctoral Dissertations

Laminitis, an inflammation of the lamina in the equine foot, is one of the least understood of the common equine diseases and is considered to be one of the greatest problems facing the horse owner and veterinarian today. The incidence of, and breed susceptibility to, this disease has never been formally assessed. Many practitioners feel that susceptibility may be related to metabolic imbalances. The purpose of this study was to tabulate current clinical information from a nationwide survey, to examine two breeds of horses, one of which has a greater incidence of laminitis, and to investigate metabolic parameters which may …

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Influence Of Genotype, Protein-Calorie Restriction And Their Interaction Upon Rsv-Induced Tumors In Chickens, Kathy Kirsten Clark Jan 1980

Influence Of Genotype, Protein-Calorie Restriction And Their Interaction Upon Rsv-Induced Tumors In Chickens, Kathy Kirsten Clark

Doctoral Dissertations

The major objective of this research was to investigate the relative contribution of genetics, nutritional restriction and the genetics by nutritional restriction interaction upon Rous sarcoma virus (RSV)-induced tumor development in chickens. Two genetic systems were used. The first involved an inbred line and a noninbred line of chickens. The second utilized F2 generation progeny from a cross of lines 6-1 and 15-1, highly inbred lines of White Leghorns from the Regional Poultry Research Laboratory of the United States Department of Agriculture at East Lansing, Michigan. These chickens had been blood typed for allcantigens coded for by genes of the …

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The Challenge And Motivation Of Students Through Live Animal Projects, Thurman S. Grafton Jan 1980

The Challenge And Motivation Of Students Through Live Animal Projects, Thurman S. Grafton

Education Collection

The subject of use of live animals by secondary schools either in classroom work or science fairs is a very controversial and often emotional issue. The author emphasizes the dedication to humane treatment of animals while at the same time explaining the process by which rules have been formulated to provide for the appropriate use of live animals. The difference between permission and mandate is clarified for the purpose of explaining the need to provide for the more effective challenge and motivation of the high achiever while still allowing for more modest undertakings by the average student The perils of …

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Understanding And Attitudes Derived From The Use Of Animals In Schools, Peter J. Kelly Jan 1980

Understanding And Attitudes Derived From The Use Of Animals In Schools, Peter J. Kelly

Education Collection

A general review of the variety of activities involving the direct use of animals which are undertaken in secondary schools. An assessment is made of their value (positive and negative) in terms of knowledge and attitudes (including ethics) which are, or might be, derived from them. Alternative methods also are reviewed with an assessment of their value in relation to live animal studies.

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Effects Of A Hepatic Toxin From The Cyanophyte, Microcystis Aeruginosa, Thomas Lee Foxall Jan 1980

Effects Of A Hepatic Toxin From The Cyanophyte, Microcystis Aeruginosa, Thomas Lee Foxall

Doctoral Dissertations

Toxic cyanobacteria bloom in eutrophic, freshwater lakes and ponds and may cause environmental, health and recreational problems during or after the massive growth of these microorganisms Microcystis aeruginosa is commonly involved in freshwater blooms and one of its toxins (microcystin) causes liver damage in birds and mammals. This study has determined the specific site of action of microcystin and characterized the hepatic damage at the ultrastructural level. Histological changes in centrilobular regions of liver tissue were noted after intraperitoneal administration in mice. Hepatic sinusoidal epithelial and hepatocyte plasma membranes ruptured with the release of cellular components that pooled with blood. …

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New Trends In International Law: The Challenges Of The Ecological Age, Richard A. Falk Jan 1980

New Trends In International Law: The Challenges Of The Ecological Age, Richard A. Falk

International Law Studies

No abstract provided.

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Endosymbiosis In The Caecum Of The Southern Green Stink Bug, Nezara Viridula (L.)., Robert Paul West Jan 1980

Endosymbiosis In The Caecum Of The Southern Green Stink Bug, Nezara Viridula (L.)., Robert Paul West

LSU Historical Dissertations and Theses

Studies to investigate possible endosymbiotic relationships within the southern green stink bug, Nezara viridula (L.), a major pest of soybeans in Louisiana, were conducted. Primary emphasis was placed on the caecum, a region of the digestive tract previously associated with microbial endosymbiosis in insects. By SEM, a monoculture of rod-shaped bacteria measuring 2.5 by 0.5 (mu)m was observed adhering to the caecal crypt walls. Examination of additional specimens revealed various morphological variations including cocci, elongated rods, and rods which were apparently budding, often found within the same specimen. Diapausing specimens appeared to be no different from reproducing individuals. TEM of …

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Biology, Reproductive Potential And The Impact Of Fishing Pressure On The Bluegill Fishery Of Pelican Lake, Uintah County, Utah, Bob D. Burdick May 1979

Biology, Reproductive Potential And The Impact Of Fishing Pressure On The Bluegill Fishery Of Pelican Lake, Uintah County, Utah, Bob D. Burdick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Certain aspects of the biology of two species of fish, bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides), and the assessment of fishing pressure upon the sport fishery of Pelican Lake, Uintah County, Utah, a 680 ha warmwater lake, were studied between April 1, 1976 and June 30, 1978. The growth rate of bluegills (sexes combined) was fairly rapid; the mean back-calculated total lengths from ages one through nine were 55, 112, 166, 194, 211, 229, 245, 256 and 259 mm. The growth of largemouth bass was 104, 194, 271, 316, 350, 405 and 416 mm …

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Factors Influencing Blood Steroid Hormone Levels In Relation To Egg Shell Quality., Ramli Bin Abdullah Jan 1979

Factors Influencing Blood Steroid Hormone Levels In Relation To Egg Shell Quality., Ramli Bin Abdullah

LSU Historical Dissertations and Theses

No abstract provided.

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Extrapituitary Regulation Of The Circadian Rhythm Of Plasma Corticosteroid Concentration In Rats., John Edward Ottenweller Jan 1979

Extrapituitary Regulation Of The Circadian Rhythm Of Plasma Corticosteroid Concentration In Rats., John Edward Ottenweller

LSU Historical Dissertations and Theses

No abstract provided.

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Ecological Partitioning By Antbirds Of A Moist Tropical Forest In Amazonian Ecuador., Dan Allen Tallman Jan 1979

Ecological Partitioning By Antbirds Of A Moist Tropical Forest In Amazonian Ecuador., Dan Allen Tallman

LSU Historical Dissertations and Theses

No abstract provided.

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Thyroid Hormones And Seasonality In The White-Throated Sparrow And Green Anole., Blaine Richard Ferrell Jan 1979

Thyroid Hormones And Seasonality In The White-Throated Sparrow And Green Anole., Blaine Richard Ferrell

LSU Historical Dissertations and Theses

No abstract provided.

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Studies On A Population Of Amnicola Peracuta (Prosobranchia: Hydrobiidae) And Its Association With A Community Of Digenea In Louisiana., Jeffrey Major Lotz Jan 1979

Studies On A Population Of Amnicola Peracuta (Prosobranchia: Hydrobiidae) And Its Association With A Community Of Digenea In Louisiana., Jeffrey Major Lotz

LSU Historical Dissertations and Theses

No abstract provided.

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Physiological Rhythms In Laying Hens And In Hens Before A Forced Molt., Richard Philip Gildersleeve Jan 1979

Physiological Rhythms In Laying Hens And In Hens Before A Forced Molt., Richard Philip Gildersleeve

LSU Historical Dissertations and Theses

No abstract provided.

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Morphological And Behavioral Polymorphism In Poecilia Latipinna Males (Pisces: Poeciliidae)., Carol Louise Luckner Jan 1979

Morphological And Behavioral Polymorphism In Poecilia Latipinna Males (Pisces: Poeciliidae)., Carol Louise Luckner

LSU Historical Dissertations and Theses

No abstract provided.

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Thermoperiodic And Photoperiodic Interaction In The Annual Cycle Of The Male Green Anole, Anolis Carolinensis., Teresa A. Noeske Jan 1979

Thermoperiodic And Photoperiodic Interaction In The Annual Cycle Of The Male Green Anole, Anolis Carolinensis., Teresa A. Noeske

LSU Historical Dissertations and Theses

No abstract provided.

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Glugea Hertwigi (Protozoa: Microsporida) In Osmerus Mordax (Teleosteii: Osmeridae): Field Ecology, Laboratory Transmission And Ultrastructural Study Of Parasite Development And The Host Cell-Parasite Interface., Ann L. Scarborough Jan 1979

Glugea Hertwigi (Protozoa: Microsporida) In Osmerus Mordax (Teleosteii: Osmeridae): Field Ecology, Laboratory Transmission And Ultrastructural Study Of Parasite Development And The Host Cell-Parasite Interface., Ann L. Scarborough

LSU Historical Dissertations and Theses

No abstract provided.

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Regulation Of The Reproductive Rates Of Diaptomid Copepods, Carl J. Watras Jan 1979

Regulation Of The Reproductive Rates Of Diaptomid Copepods, Carl J. Watras

Doctoral Dissertations

No abstract provided.

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Macromolecular Synthesis Of Cellulomonas Grown In Continuous Culture., Richard Joseph Summers Jan 1979

Macromolecular Synthesis Of Cellulomonas Grown In Continuous Culture., Richard Joseph Summers

LSU Historical Dissertations and Theses

No abstract provided.

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Ultrastructure Of Purified Toxoplasma Gondii And Characterization Of Its Pellicle., Jean Carol Tryon Jan 1979

Ultrastructure Of Purified Toxoplasma Gondii And Characterization Of Its Pellicle., Jean Carol Tryon

LSU Historical Dissertations and Theses

No abstract provided.

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Circadian Neurotransmitter Activity Regulating Seasonal Conditions In Three Avian Species., Larry John Miller Jan 1979

Circadian Neurotransmitter Activity Regulating Seasonal Conditions In Three Avian Species., Larry John Miller

LSU Historical Dissertations and Theses

No abstract provided.

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