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The Ontogeny And Functional Significance Of Luteinizing Hormone Releasing Hormone (Lhrh) Containing Centers Of The Brain Of The Freshwater Teleost, Xiphophorus Maculatus, Leslie R. Halpern-Sebold Jan 1984

The Ontogeny And Functional Significance Of Luteinizing Hormone Releasing Hormone (Lhrh) Containing Centers Of The Brain Of The Freshwater Teleost, Xiphophorus Maculatus, Leslie R. Halpern-Sebold

Dissertations, Theses, and Capstone Projects

The use of cytometric, immunocytochemical and radioimmunological methods has allowed the investigation of the ontogeny and functional significance of LHRH containing centers in sibling platyfish (Xiphophorus maculatus) genetically determined to reach sexual maturity at different ages and in adult fish which were hypophysectomized and given replacement therapy with gonadotropin.

There is a sequential development of three immunoreactive (ir-) LHRH centers in the brain that is directly related to stage, not age of sexual maturation. The first region to contain ir-LHRH is the nucleus olfactoretinalis (NOR). Ir-LHRH then appears in the nucleus preopticus periventricularis (NPP), followed by the nucleus lateralis tuberis …


The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of The Male Mongolian Gerbil (Meriones Unguiculatus), Luis Jose Cova Marchan Jan 1984

The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of The Male Mongolian Gerbil (Meriones Unguiculatus), Luis Jose Cova Marchan

Master's Theses

This work was undertaken to study the effects of photoperiod and melatonin on fertility in male Mongolian gerbils (Meriones unguiculatus). Four groups of fifteen animals each, were placed in different photoperiods (ambient, ranging from 14L:10D to 11.3L:12.3D; 24L:10D; 14L:10D; and 1L:23D). After 35 days, three gerbils from each photoperiod condition were sacrificed and the testes, epididymides, seminal vesicles, prostate, kidneys, adrenals, thymus and hypophysis were weighed. The testes and epididymides were placed in Bouin's fixative and used for histological studies. Also, two males from each photoperiod condition were paired individually with a female. The remaining animals of each photoperiod condition …


Factors Affecting Reproductive Success Of Bonytail Chubs And Razorback Suckers In Lake Mohave, Michael A. Bozek, Larry J. Paulson, James E. Deacon, U.S. Department Of Interior, Fish And Wildlife Service Jan 1984

Factors Affecting Reproductive Success Of Bonytail Chubs And Razorback Suckers In Lake Mohave, Michael A. Bozek, Larry J. Paulson, James E. Deacon, U.S. Department Of Interior, Fish And Wildlife Service

Publications (WR)

Razorback suckers (Xyrauchen texanus) and bonytail chubs (Gila elegans) were once widespread throughout the Colorado River system. The ranges and populations of these native species and others have declined in the past 50 years. Bonytail chubs appear to be extremely rare and possibly nearing extinction in the Upper Colorado River Basin. The razorback sucker is widely distributed in the upper river but is considered rare throughout most of that range and is also rare in the Grand Canyon. Razorback suckers are abundant only in a few habitats in the upper river. They congregate and spawn over …


Factors That Influence Plant Species Richness On Habitat Islands Of Sand Pine Scrub, Cindy B. Connery Jan 1984

Factors That Influence Plant Species Richness On Habitat Islands Of Sand Pine Scrub, Cindy B. Connery

Retrospective Theses and Dissertations

No abstract provided.


Leptodactylus Podicipinus (Cope, 1862) Y Leptodactylus Chaquensis Cei, 1959 (Anura, Leptodactylidae), En El Uruguay, Raúl Vaz-Ferreira, Rafael O. De Sá, Federico Achaval, Annelise Gebrau Jan 1984

Leptodactylus Podicipinus (Cope, 1862) Y Leptodactylus Chaquensis Cei, 1959 (Anura, Leptodactylidae), En El Uruguay, Raúl Vaz-Ferreira, Rafael O. De Sá, Federico Achaval, Annelise Gebrau

Biology Faculty Publications

En base al estudio de las colecciones obtenidas principalmente en excursiones a la zona NO de Uruguay con motivo del relevamiento faunístico del área de Salto Grande, se avanzó considerablemente en el conocimiento de la distribución de Leptodactylus podicipinus (Cope, 1862) y Leptodactylus chaquensis (Cei, 1950), en nuestro país.

Se cita el material estudiado y las observaciones de campo realizadas; se dan los caracteres generales de ambas especies, se describen los hábitats, y se tratan las características de las vocalizaciones.


Determination Of An Enzyme Deficiency In The Saccharomyces Cerevisiae Mutant Mod5-1, Lacking Isopentenylated Trnas, Sopiah Suid Jan 1984

Determination Of An Enzyme Deficiency In The Saccharomyces Cerevisiae Mutant Mod5-1, Lacking Isopentenylated Trnas, Sopiah Suid

Master's Theses

No abstract provided.


Non-Visual Feeding Behavior Of The Mottled Sculpin Cottus Bairdi: Ecological And Evolutionary Implications, Denise Maxine Denham Hoekstra Jan 1984

Non-Visual Feeding Behavior Of The Mottled Sculpin Cottus Bairdi: Ecological And Evolutionary Implications, Denise Maxine Denham Hoekstra

Master's Theses

No abstract provided.


Radiological Monitoring Of Select Faunal Species Indigenous To Environs Of The Maxey Flats Shallow Land Burial Facility, Robert Bruce Burns Dec 1983

Radiological Monitoring Of Select Faunal Species Indigenous To Environs Of The Maxey Flats Shallow Land Burial Facility, Robert Bruce Burns

Morehead State Theses and Dissertations

A Thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Robert Bruce Burns on December 14, 1983.


The Effects Of Photoperiod On The Prolactin Cells Of Notropis Cornutus (Mitchell), Matthew Kevin Hettinger Dec 1983

The Effects Of Photoperiod On The Prolactin Cells Of Notropis Cornutus (Mitchell), Matthew Kevin Hettinger

Masters Theses

Three groups of the common shiner (Notropis cornutus, Mitchell) were adapted to three different photoperiods. These photoperiods were 16L:8D (summer), 12L:12D (controls), and 8L:16D (winter). The prolactin cells were studied histologically and morphologically with respect to staining characteristics, cell and nuclear morphology, nuclear size, and cellular density. The prolactin cells of those fish under the long photoperiod exhibited greater cellular activity than the controls as evidenced by an increase in nuclear size, cellular density, and by becoming more circular. The prolactin cells of those fish under the short photoperiod exhibited the same characteristics as those in the long photoperiod. The …


A Study Of The Environmental Aspects Of Schistosomiasis In Libya, Abubaker I. Swehli Dec 1983

A Study Of The Environmental Aspects Of Schistosomiasis In Libya, Abubaker I. Swehli

Dissertations

Schistosomiasis is a serious disease in humans. Two species of schistosome, Schistosoma mansoni and Schistosoma haematobium, organisms that cause the disease, parasitize humans in Libya. Schistosomes require aquatic snails in their life cycle. The purpose of this study was to investigate the environmental and the host relationships of the disease in the three regions of Libya where the disease is found. These relationships include:

1) Analyses of the physical-chemical characteristics of the aquatic habitat.

2) Collection of snails to determine: a) the kind of snail species and th e ir abundance; and b) the cercarial infestation rates.

3) Infection rates …


Histopathology In Rat Temporal Bones Resulting From Excess Dietary Fluoride In Conjunction With Suspected Water Born Toxins, Donna Lee Healy Dec 1983

Histopathology In Rat Temporal Bones Resulting From Excess Dietary Fluoride In Conjunction With Suspected Water Born Toxins, Donna Lee Healy

Masters Theses

The occurrence of perinatal deaths, bony extoses, and deafness in dog kennels in certain areas of Michigan led The Upjohn Company and Western Michigan University to suspect fluoride toxicity and/or water born toxins. The present project was designed to examine the ability of excess fluoride ingestion and/or the ability of suspected water born toxins to induce histopathology in Sprague-Dawley rats. An otopathological assessment of the rat temporal bones showed no otopathology nor any changes in cochlear dimensions, however, a quantitative assessment of osteoclastic density showed a large increase in the numbers of osteoclasts of spongy bone in the high fluoride …


The Effect Of Orally Administered Butylated Hydroxytoluene On Herpes Simplex Keratitis, Donald Carson Nov 1983

The Effect Of Orally Administered Butylated Hydroxytoluene On Herpes Simplex Keratitis, Donald Carson

Masters Theses & Specialist Projects

Some studies have reported in vitro inactivation of membrane enveloped viruses by Butylated hydroxytoluene (BHT). This study investigates the effect of orally administered BHT on primary infections of Herpes simplex virus (HSV) using rabbit corneas as the assay system.

Assigned levels of BHT were incorporated into the diet of New Zealand White rabbits with HSV-1 McKrae strain on the corneal surface of the eyes. The degree of infection was measured by a subjective assay. Rabbits receiving BHT in their diet consistently experienced lower levels of infection. The interpretation of this data is that orally administered BHT can be an effective …


Analysis Of Estrogen And Progesterone Binding Sites In Cytosol And Nuclei Of 7,12-Dimethybenz (A) Anthracene-Induced Rat Mammary Carcinoma: Hormone-Dependent Vs. Hormone Independent Tumor Populations, Danny Michael Burns Sep 1983

Analysis Of Estrogen And Progesterone Binding Sites In Cytosol And Nuclei Of 7,12-Dimethybenz (A) Anthracene-Induced Rat Mammary Carcinoma: Hormone-Dependent Vs. Hormone Independent Tumor Populations, Danny Michael Burns

Morehead State Theses and Dissertations

A thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirement for the Degree of Master of Science in Biology by Danny Michael Burns on September 6, 1983.


Fish Names Of Wallis Island (Uvea), Karl H. Rensch Sep 1983

Fish Names Of Wallis Island (Uvea), Karl H. Rensch

Pacific Studies

No abstract provided.


Binding Activity Of The Tubulin-3h-Colchicine Complex, Menjor Tino Unlap Aug 1983

Binding Activity Of The Tubulin-3h-Colchicine Complex, Menjor Tino Unlap

Masters Theses & Specialist Projects

Microtubules, isolated from bovine brain, were used to study the effect of ultraviolet radiation on the tubulin-3H-colchicine complex and the polymerizing ability of this complex to intact and disrupted microtubules. Dissociation of this complex was observed upon ultraviolet irradiation and continued to progress as exposure time increased. The binding of this complex to intact microtubules prior to irradiation did not seem to enhance its stability to ultraviolet radiation. There was a significant difference observed at the 0.05 level between the binding of the tubulin-3H-colchicine complex to microtubules in mechanically disrupted and control samples. Statistically, there was …


The Role Of Adrenomedullary Hormones In Survival Of The Adrenalectomized Mongolian Gerbil, Meriones Unguiculatus, Carol B. Ussery Aug 1983

The Role Of Adrenomedullary Hormones In Survival Of The Adrenalectomized Mongolian Gerbil, Meriones Unguiculatus, Carol B. Ussery

Master's Theses

Thee effects of adrenalectomy and catecholamine replacement therapy on survival were studied in Meriones unguiculatus, the Mongolian gerbil. Adrenalectomized gerbils that received epinephrine lived significantly longer than the controls untreated adrenalectomized gerbils) and animals that received either norepinephrine or a combination of epinephrine and norepinephrine. Results also indicated that these epinephrine-treated animals lost more depot fat that either controls or other groups receiving treatment. In spite of the short survival benefit given by epinephrine, the mechanisms governing the critical adrenal dependency in this species remain unknown.


The Role Of The Adrenal Cortex In Fat Metabolism Of Meriones Unguiculatus, The Mongolian Gerbil, Saffia Baggia Aug 1983

The Role Of The Adrenal Cortex In Fat Metabolism Of Meriones Unguiculatus, The Mongolian Gerbil, Saffia Baggia

Master's Theses

The effects of adrenalectomy and corticoid replacement therapies on survival, weight loss, depot fat and blood free fatty acid were studied in Meriones unguiculatus, the Mongolian gerbil. Adrenalectomized gerbils that received cortisol and aldosterone lived significantly longer and lost significantly more weight than the controls (adrenalectomized gerbils not receiving any treatment) and the sham-operated groups. Cortisol and aldosterone treatment were also effective in mobilizing significantly greater amounts of depot fat into free fatty acid. Cortisol and aldosterone treated groups had significantly less blood free fatty acid than the control and the sham-operated groups.


Interaction Of Nutrition And Infection: Effect Of Zinc Deficiency On Immunoglobulin Levels In Trypanosoma Musculi Infection, Clarence Lee, Patricia Humphrey, Georgiana Aboko-Cole Jul 1983

Interaction Of Nutrition And Infection: Effect Of Zinc Deficiency On Immunoglobulin Levels In Trypanosoma Musculi Infection, Clarence Lee, Patricia Humphrey, Georgiana Aboko-Cole

Department of Biology Faculty Publications

Accumulative evidence in the scientific literature relating malnutrition and susceptibility to infection in human beings and animals has contributed significantly to the understanding of the maladies among the malnourished of the world. In the dispensation of health care systems around the world, little or no emphasis has been placed on trace-element nutrition. This paper adds to the available evidence by using a metabolic imbalance technique to investigate the effects zinc deficiency exert on the course of a parasitic infection. A model composed of zinc-deficient mice and Trypanosoma musculi was used to study changes in serum immunoglobulins.


Food Supplementation Of Small Rodents In The Sand Pine Scrub, Brenda L. Young Jul 1983

Food Supplementation Of Small Rodents In The Sand Pine Scrub, Brenda L. Young

Retrospective Theses and Dissertations

No abstract provided.


Baseline Study For Monitoring Variations In Nitrate Concentration In Surface Waters Of Cuyamaca Rancho State Park In Relation To Watershed Types, Lester E. Harris Iii Jun 1983

Baseline Study For Monitoring Variations In Nitrate Concentration In Surface Waters Of Cuyamaca Rancho State Park In Relation To Watershed Types, Lester E. Harris Iii

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to compare the variations in nitrate concentration in the surface waters of five different watershed community types at Cuyamaca Rancho State Park. Monthly water samples were collected at selected sites below each watershed and analyzed by use of a specific ion electrode for nitrate concentration. Results indicate that variations in nitrate concentration are influenced by seasonal variation in rainfall. The yellow pine forest/chaparral watershed showed the highest mean nitrate concentration, three to four times higher than the other watershed types analyzed. Peak nitrate concentrations did not approach the maximum safe limit for human or …


Food Habits & The Utilization Of Drift Organisms By Larval Fishes In The Middle Fork Of Drake's Creek, Kentucky, Shirley Timbrook May 1983

Food Habits & The Utilization Of Drift Organisms By Larval Fishes In The Middle Fork Of Drake's Creek, Kentucky, Shirley Timbrook

Masters Theses & Specialist Projects

Food habits of larvae of the northern hog sucker, common shiner, rosyface shiner, and Micropterus sp. from the Middle Fork of Drake's Creek, Kentucky were identified from 18 March to 12 August 1982. Eighteen taxa of animals were observed in the stream drift and a total of seventeen taxa, including larval fish, were identified in the stomach analysis. Eggs, rotifers, hydracarina, and diptera represented the greatest component of the drift comprising 34%, 32%, 8%, and 6%, respectively. The major organisms observed in the gut analysis included eggs (fish, rotifer, and copepod species), rotifers (Euchlanis sp.), diptera (Chironomidae), annelida (Naididae), …


Chronology Of Appearance & Habitat Partitioning By Stream Larval Fishes, Keith Floyd May 1983

Chronology Of Appearance & Habitat Partitioning By Stream Larval Fishes, Keith Floyd

Masters Theses & Specialist Projects

Larval fish were studied on the Middle Fork of Drake's Creek from 18 March 1982 to 9 September 1982. A total of 6,057 individuals representing 28 species and six unidentified cyprinids was collected. Micropterus sp. was the dominant species representing 33% of the total. Most of the remaining taxa were,generally,equally represented. Juvenile banded sculpins were the first larvae observed -- followed by darters, suckers, minnows, and sunfishes. The percid species, logperch, greenside darter, and Etheostoma (Ulocentra), illustrated the longest spawning periods, their larvae being taken from 24 March to 8 July. Maximum species occurrence was observed from 7 July …


Ua66/6/2 Alumni Newsletter, Wku Biology May 1983

Ua66/6/2 Alumni Newsletter, Wku Biology

WKU Administration Documents

Newsletter created by and about the WKU Biology department highlighting students, faculty and alumni activities.


Nest Success And Nesting Habits Of Eastern Kingbirds And Other Flycatchers, Michael T. Murphy May 1983

Nest Success And Nesting Habits Of Eastern Kingbirds And Other Flycatchers, Michael T. Murphy

Biology Faculty Publications and Presentations

Patterns of nest placement and its relationship to nest success in the Eastern Kingbird (Tyrannus tyrannus) were studied in populations breeding in New York and Kansas. Data were augmented with information on nest placement in other open-nesting tyrannids in order to examine the hypothesis that these flycatchers place their nests chiefly so as to conceal them from predators. Nesting success was significantly greater in New York than in Kansas but was relatively high in both populations, as is apparently true of North American breeding flycatchers in general. Geographic variation in nest placement in the Eastern Kingbird was relatively small and …


Effect Of Hindlimb Immobilization On The Fatigability Of Skeletal Muscle, Frank Arthur Witzmann, D. H. Kim, Robert H. Fitts May 1983

Effect Of Hindlimb Immobilization On The Fatigability Of Skeletal Muscle, Frank Arthur Witzmann, D. H. Kim, Robert H. Fitts

Biological Sciences Faculty Research and Publications

The soleus (SOL) and extensor digitorum longus (EDL) muscles of the rat were studied in situ (33.5ºC) after 6 wk of disuse atrophy produced by hindlimb immobilization (IM). IM resulted in depressed peak twitch (Pt) and tetanic (P0) tension as well as a decreased rate of tension development (+dP/dt) and decline (-dP/dt) in the slow-twitch SOL. The fast-twitch EDL was affected to a lesser extent, because only Po (g·cm-2) and Po,-dP/dt (g·cm-2·ms-1) were depressed after IM. Twitch duration, as measured by contraction …


Natural Killer Activity In Gardner's Syndrome, Ann Marie Stembridge May 1983

Natural Killer Activity In Gardner's Syndrome, Ann Marie Stembridge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gardner's syndrome is an autosomal dominant disease presenting multiple colonic polyps with a predisposition for malignant change. In addition to colonic polyp formation by early adolescence, extracolonic lesions appear often prior to polyp formation. One theoretical mechanism for the origin of polyps and malignancies in Gardner's syndrome is a genetic defect in the natural killer cell activity of patients with this disease. Natural killer cells are a subpopulation of lymphocytes that spontaneously lyse tumor cells and virally transformed cells. A study was undertaken to determine the natural killer activity of patients with Gardner's syndrome.

A technique termed chromium release was …


Effects Of Physical And Emotional Stress, Catecholamines And Naloxone On Hdl And Ldl Cholesterol Levels In Rats And Man, Andrew G. Goliszek May 1983

Effects Of Physical And Emotional Stress, Catecholamines And Naloxone On Hdl And Ldl Cholesterol Levels In Rats And Man, Andrew G. Goliszek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of investigations were undertaken to determine whether physical or emotional stress, catecholamines or naloxone (B-endorphon blocker) would increase serum total cholesterol and LDL and HDL levels. Physical stress given daily over a period of time caused a steady increase in serum total cholesterol and LDL without a significantly altering high density lipoproteins (HDL) or serum triglycerides. Daily injections of epinerphrine in oil caused an increase in both serum total cholesterol and LDL levels while daily injections of norepinephrine did not. Reversal of the treatments caused a reversed response in both groups of rats. Similar increases in both total …


Alteration In Serum Enzyme Levels, Activity Of Hepatic Monooxygenases, And Hepatocyte Morphology Due To Liver Enzyme Inducers In Microtus Montanus, Jeffrey Robert Hincks May 1983

Alteration In Serum Enzyme Levels, Activity Of Hepatic Monooxygenases, And Hepatocyte Morphology Due To Liver Enzyme Inducers In Microtus Montanus, Jeffrey Robert Hincks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microtus sp. have been used in microcosm simulations of polluted environments. In this study, female Microtus montanus (mountain vole), 8 - 12 weeks of age, were pretreated with phenobarbital (PB), ß-naphthoflavone (BNF), or Aroclor 1254 (PCB) for 3 consecutive days. Doses ranged from 5 to 80 mg/kg for each pretreatment, while control animals received saline or corn oil only. The voles were sacrificed 1 day after the last dose of PB and 2 days after BNF and PCB. Hepatic microsomal enzyme activity of aniline hydroxylase (AH), p-nitroanisole-O-demethylase (PNA) and cytochrome C reductase (CCR) were measured in relation …


Creative Mechanists: Putting Things In Order (Text And Audio), J. Robert Hippensteele Apr 1983

Creative Mechanists: Putting Things In Order (Text And Audio), J. Robert Hippensteele

Honorees for Teaching Excellence

This Century Club presentation is titled "Creative Mechanists: Putting Things in Order." The text of the speech is available for download above and to the right; it was published in the July 1983 IWU Bulletin, see https://collections.carli.illinois.edu/digital/collection/iwu_bullet/id/3069/rec/6


An Evaluation Of Small Rodents In Four Dismal Swamp Plant Communities, F. Elizabeth Breidling, Frank P. Day Jr., Robert K. Rose Apr 1983

An Evaluation Of Small Rodents In Four Dismal Swamp Plant Communities, F. Elizabeth Breidling, Frank P. Day Jr., Robert K. Rose

Biological Sciences Faculty Publications

Diversity and density of small rodents in the Dismal Swamp are believed to be low. Reasons for this may be excessive predation, heavy interspecific pressure from large rodents, lack of suitable habitat, low food availability or flooding.

Rodent populations were evaluated using live-traps and pitfall traps in four different Dismal Swamp plant communities. Habitat was compared on the basis of phytomass studies previously reported. Flood levels were recorded during live-trapping sessions. Mast from trees was collected in modified mast collectors, and fed to Peromyscus leucopus in the laboratory.

Only two small rodent species were captured: Ochrotomys nuttalli and Peromyscus leucopus …