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The Influence Of Lake Powell On The Suspended Sediment-Phosphorus Dynamics Of The Colorado River Inflow To Lake Mead, T. D. Evans, Larry J. Paulson Jan 1983

The Influence Of Lake Powell On The Suspended Sediment-Phosphorus Dynamics Of The Colorado River Inflow To Lake Mead, T. D. Evans, Larry J. Paulson

Publications (WR)

The Colorado River has been successively modified by the construction of several reservoirs, beginning in 1935 with the formation of Lake Mead by Hoover Dam. These reservoirs are located in a chain, and each one has an influence on the nutrient dynamics and productivity of the river and downstream reservoir. Lake Mead derives 98% of its annual inflow from the Colorado River. Historically, the Colorado River inflow was unregulated into Lake Mead. Regulation occurred in 1963, when Lake Powell was impounded by the construction of Glen Canyon Dam, approximately 450 km upstream. The formation of Lake Powell drastically altered the …


Breeding Behavior Of Captive Emperor Penguins (Aptenodytes Forsteri), Mary Elizabeth Kiel Jan 1983

Breeding Behavior Of Captive Emperor Penguins (Aptenodytes Forsteri), Mary Elizabeth Kiel

University of the Pacific Theses and Dissertations

Breeding behavior of captive Emperor Penguins (Aptenodytes forsteri) was observed at Sea World, San Diego, California during July, August, and September 1980, and April 1981. Emphasis was on displays, courtship, egg-laying, incubation, and care of chicks.

I observed the trumpet display most often between birds of opposite sexes and I interpret it as a signal of sexual identity. I interpreted the sideways stare display as a signal of sexual identity important in pair bond maintenance. Three head movements studied shared several functions including comfort behavior and reduction of intraspecific aggression. My observations confirmed that the display walk occurs in Emperors …


Defensive Adaptations And Natural Enemies Of A Case-Bearing Beetle, Exema Canadensis (Coleoptera: Chrysomelidae), R. B. Root, Frank J. Messina Jan 1983

Defensive Adaptations And Natural Enemies Of A Case-Bearing Beetle, Exema Canadensis (Coleoptera: Chrysomelidae), R. B. Root, Frank J. Messina

Biology Faculty Publications

The larval habit of constructing and carrying a portable case has evolved many times in the Holometabola. It is a widespread trait of the Trichoptera and Lepidoptera (e.g. the Coleophoridae and Psychidae). Among the Coleoptera, casebearing is found in four related subfamilies of the Chrysomelidae, the so-called camptosomates: Clytrinae, Cryptocephalinae, Chlamisinae, and Lamprosomatinae (B6ving and Craighead 1931). The larval case of many insects is thought to function primarily in defense by providing armor or camouflage (Otto and Svensson 1980). Here we describe the uses of the case and other defenses in a chlamisine beetle, Exerna canadensis Pierce, and speculate briefly …


An Ultrastructural Study Of The Encapsulation Response Of The American Cockroach, Periplaneta Americana, Candace Ann Ennesser Jan 1983

An Ultrastructural Study Of The Encapsulation Response Of The American Cockroach, Periplaneta Americana, Candace Ann Ennesser

Master's Theses

No abstract provided.


Prevalence Of Baylisascaris Procyonis In Northern Illinois And Larval Migration In The Mongolian Gerbil (Meriones Unguiculatus), Diane Mary Sudduth Jan 1983

Prevalence Of Baylisascaris Procyonis In Northern Illinois And Larval Migration In The Mongolian Gerbil (Meriones Unguiculatus), Diane Mary Sudduth

Master's Theses

No abstract provided.


The Role Of Lh Pulses On In Vitro Follicular Development In The Metestrous Rat Ovary, Shirley Jane Luttmer Jan 1983

The Role Of Lh Pulses On In Vitro Follicular Development In The Metestrous Rat Ovary, Shirley Jane Luttmer

Master's Theses

No abstract provided.


An Ecological Succession Model Applied To Environmental Management, Diane Rosenberg Jan 1983

An Ecological Succession Model Applied To Environmental Management, Diane Rosenberg

Master's Theses

No abstract provided.


Habitat Selection Related To Resource Availability Among Cavity-Nesting Birds, Timothy Brush Jan 1983

Habitat Selection Related To Resource Availability Among Cavity-Nesting Birds, Timothy Brush

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Variation in snag species and abundance appeared to explain most of the habitat selection patterns observed in five cavity-nesting riparian species over a three-year period. All species except Ash-throated Flycatchers were most common in areas with cottonwood or willow snags, which have relatively soft wood and are preferred nest sites. Classification of habitats on the basis of nest-site characteristics was useful and should be considered in other habitat selection studies.


Coxsackievirus B4 Induced Diabetes In Cd-1 Mice, Mary C. F. Anderson Jan 1983

Coxsackievirus B4 Induced Diabetes In Cd-1 Mice, Mary C. F. Anderson

Theses and Dissertations

Most evidence to date clearly indicates that CB4 virus can affect the pancreas of both man and mice during acute infection. Yet, conflicting evidence exists relative to the consequence of the infection in both man and mice. The study described here attempted to provide definitive evidence on the relative role of the virus isolate (i.e. heterogenous virion populations vs. purified clones) in induction of prolonged diabetes-like disease in mice.


Protein Contributions Of The Male Accessory Organs To The Composition Of Human Seminal Plasma As Determined By High Resolution Two-Dimensional Electrophoresis, Edward E. Gaunt Jan 1983

Protein Contributions Of The Male Accessory Organs To The Composition Of Human Seminal Plasma As Determined By High Resolution Two-Dimensional Electrophoresis, Edward E. Gaunt

Theses and Dissertations in Biomedical Sciences

Human Seminal Plasma was evaluated using a High Resolution Two-Dimensional Electrophoresis technique adapted by this laboratory. Seminal plasma from healthy volunteers with recently proven fertility were characterized using this technique to establish "normal" protein distribution patterns in the two-dimensional polyacrylamide gel slab. In addition, time studies were performed on selected specimens to determine the effects of liquefaction on seminal plasma protein composition within the first several hours after collection. Split ejaculates were collected for identification and elaboration of accessory organ components in the whole seminal plasma specimen. A more direct approach to accessory organ component analysis involved electrophoresis of semen …


A Natural Areas Inventory Of Black Hawk County, Iowa, Mary Frances Duritsa Jan 1983

A Natural Areas Inventory Of Black Hawk County, Iowa, Mary Frances Duritsa

Dissertations and Theses @ UNI

Black Hawk County is a 576 square mile political subdivision located in the northeast quadrant of Iowa in the physiographic region known as the Iowan Surface. The purpose of this study was to determine the status of natural areas within the county. Four aspects were investigated: (i) the amount and qualitative condition of the woodland (ii) the identification, verification and qualitative assessment of specific natural communities with emphasis on prairies, wetlands and forests; (iii) the identification and verification of threatened and endangered species as reported in Endangered Io;.va Vertebrates (Roosa, 1977) and Endangered and Threatened Iowa Vascular Plants (Roosa and …


Serial Cardiovascular Adaptations During Pregnancy, Mark Vincent Hart Jan 1983

Serial Cardiovascular Adaptations During Pregnancy, Mark Vincent Hart

Dissertations and Theses

Maternal cardiovascular adaptations appear to be essential in order to supply extra circulation to both the developing fetus and maternal system during a successful pregnancy. Since inadequate cardiovascular adjustments may produce abortions or maternal morbidity, the characterization of maternal cardiovascular changes during pregnancy and the elaboration of the underlying mechanism for these changes are essential to the understanding of how the heart enlarges during pregnancy and what significance this enlargement might have. To provide needed information regarding this time course and extent of maternal cardiac enlargement and the hormonal and hemodynamic changes which may be responsible for these changes, the …


The Absence Of Extrachromosomal Dna In Methanogenic Bacteria, Nancy Ann Kurkinen Jan 1983

The Absence Of Extrachromosomal Dna In Methanogenic Bacteria, Nancy Ann Kurkinen

Dissertations and Theses

Five species of methanogenic bacteria were analyzed for the presence of plasmid DNA. Several procedures for the detection and isolation of covalently closed circular plasmid DNA were modified for use with the methanogens.


Population Structure, Density And Movements Of The Texas Tortoise Gopherus Berlandieri, Frank W. Judd, Francis L. Rose Jan 1983

Population Structure, Density And Movements Of The Texas Tortoise Gopherus Berlandieri, Frank W. Judd, Francis L. Rose

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Gopherus berlandieri was studied on a 3.3 ha grid in Cameron Co., Texas for five years. One hundred two tortoises were marked (43 males, 30 females, 26 juv., and 3 adults whose sex was not determined). Numbers of males and females did not differ significantly. Juveniles comprised 27% to 9% of the population and maximum population density was 15 to 16 tortoises per ha. The number of females remained constant, but males and juveniles declined gradually from 1972 to 1975, then markedly in 1976. The percentage of shared individuals in successive years was higher for females than males, but only …


The Effects Of Photoperiod-Temperature Interactions On Testicular Regression In The Green Anole, Anolis Carolinensis, Teri Wickelhaus Dec 1982

The Effects Of Photoperiod-Temperature Interactions On Testicular Regression In The Green Anole, Anolis Carolinensis, Teri Wickelhaus

Masters Theses & Specialist Projects

Interrupted-night photoperiod experiments were carried out in green anoles (Anolis carolinensis) in July and August 1981 in order to explore the possibility that seasonal timing of testicular regression regulated by day length involves circadian rhythms. The influence that temperature has on testicular responsiveness to light was also assessed. Testicular weight responses to different interrupted-night photoperiod treatments were similar in anoles kept at constant warm temperatures but varied in anoles kept at constant cold temperatures. Rates of decline of spermatogenesis in response to different interrupted-night photoperiod treatments were, on the other hand, similar in anoles kept at constant cold …


Effects Of Wastewater Discharges On Periphyton Growth In Lake Mead, Nevada-Arizona, Marsha Korb Morris Dec 1982

Effects Of Wastewater Discharges On Periphyton Growth In Lake Mead, Nevada-Arizona, Marsha Korb Morris

Publications (WR)

A study of the effects of secondary-treated wastewater on periphyton growth in Lake Mead, Nevada-Arizona was conducted from September 1979 to December 1980. Periphyton ash-free dry weight, chlorophyll-a, dominant species composition, and alkaline phosphatase activity were measured on fiberglass substrates. Substrates were incubated for two to four weeks in littoral and limnetic habitats. Physical and chemical variables and phytoplankton chlorophyll-a were measured concurrently.

Transparency increased with increasing distance from the discharge. Secchi depth ranged from 0.75 m at the discharge confluence (station 2) in August, to greater than 20 m at the most distant stations (stations 9 and 10) in …


The Effect Of Dwarf Mistletoe (Arceuthobium Americanum) Upon A Portion Of The Carbon Budget Of Lodgepole Pine (Pinus Contorta), Nancy Ellen Broshot Nov 1982

The Effect Of Dwarf Mistletoe (Arceuthobium Americanum) Upon A Portion Of The Carbon Budget Of Lodgepole Pine (Pinus Contorta), Nancy Ellen Broshot

Dissertations and Theses

Arceuthobium americanum is a vascular plant which is parasitic upon Pinus contorta var. murrayana. Its documented effects include reductions in host growth, vigor and wood quality. The specific physiological changes that occur in the host are, for the most part, unknown.

In an attempt to understand the manner in which the mistletoe alters its host's carbon budget, a model is proposed which states that the host plant has priorities for carbon allocation. The model proposes that the parasite will access the host's carbon initially in terms of carbon intended for storage, next, in terms of carbon intended for growth, …


Responses Of Estuarine Infauna To Disturbance. I. Spatial And Temporal Variation Of Initial Recolonization, Roman N. Zajac, Robert B. Whitlatch Nov 1982

Responses Of Estuarine Infauna To Disturbance. I. Spatial And Temporal Variation Of Initial Recolonization, Roman N. Zajac, Robert B. Whitlatch

Biology and Environmental Science Faculty Publications

Responses to disturbance of estuarine infauna were studied to test the hypothesis that seasonality, the estuarine environmental gradient and sediment composition would significantly affect recolonization. The study was conducted in a small estuary located in southeastern Connecticut, USA, using controlled disturbance experiments and sampling of the ambient infauna. Species composition in experimental plots and ambient sediments usually did not differ, either on a seasonal or areal basis. Numerically dominant species usually included the polychaetes Streblospio benedicti, Capitella spp. and Polydora ligni, and the oligochaete Peloscolex gabriellae. Other species included the polychaetes Scoloplos fragilis, Hobsonia florida and Nereis …


Responses Of Estuarine Infauna To Disturbance. Ii. Spatial And Temporal Variation Of Succession, Roman N. Zajac, Robert B. Whitlatch Nov 1982

Responses Of Estuarine Infauna To Disturbance. Ii. Spatial And Temporal Variation Of Succession, Roman N. Zajac, Robert B. Whitlatch

Biology and Environmental Science Faculty Publications

Infaunal successional patterns in Alewife Cove, a small estuary in southeastern Connecticut, USA, varied significantly seasonally and along the estuarine environmental gradient. Each study site exhibited different patterns of change in species composition and abundance. However, suites of species found during succession did not differ greatly from those found in ambient sediments. Species which exhibited the most variable population changes during succession were numerically dominant tubiculous polychaetes (Streblospio benedicti, Capitella spp., Polydora ligni], and an oligochaete (Peloscolex gabriellae). Other species which exhibited significant activity were the polychaetes Scoloplos fragilis, Hobsonia florida and Nereis virens, the hemichordate Saccoglossus kowaleski, and the …


Reproductive Biology Of The Rat Lungworm Angiostrongylus Cantonensis (Metastrongyloidea: Angiostrongylidae), Grace Spatafora Harris Nov 1982

Reproductive Biology Of The Rat Lungworm Angiostrongylus Cantonensis (Metastrongyloidea: Angiostrongylidae), Grace Spatafora Harris

Master's Theses

Twenty rats (Rattus norvegicus) received infective inocula of 5, 10, 20, and 40 third-stage larvae of Angiostrongylus cantonensis. The effects of varying doses of larvae on prepatent period larval production, worm establishment, worm size, and fertility were studied. The aquatic gastropod Biomphalaria glabratta was the experimental intermediate host.

The duration of the prepatent period varied from 37 to 45 days. The shortest prepatent period was observed in animals that received the highest infective inoculum. The prepatent period showed a significant inverse relationship with increasing inoculum size. Larval production increased logarithmically, followed by a plateau phase. The number of larvae per …


Rhizobium Japonicum Mutants Defective In Symbiotic Nitrogen Fixation, K. Dale Noel, Gary Stacey, Lin E. Silver, Winston J. Brill, Shiv R. Tandon Oct 1982

Rhizobium Japonicum Mutants Defective In Symbiotic Nitrogen Fixation, K. Dale Noel, Gary Stacey, Lin E. Silver, Winston J. Brill, Shiv R. Tandon

Biological Sciences Faculty Research and Publications

Rhizobium japonicum strains 3I1b110 and 61A76 were mutagenized to obtain 25 independently derived mutants that produced soybean nodules defective in nitrogen fixation, as assayed by acetylene reduction. The proteins of both the bacterial and the plant portions of the nodules were analyzed by two-dimensional polyacrylamide gel electrophoresis. All of the mutants had lower-than-normal levels of the nitrogenase components, and all but four contained a prominent bacteroid protein not observed in wild-type bacteroids. Experiments with bacteria grown ex planta suggested that this protein was derepressed by the absence of ammonia. Nitrogenase component II of one mutant was altered in isoelectric point. …


Intellectual Traditions In The Life Sciences: Molecular Biology And Biochemistry, Scott F. Gilbert Oct 1982

Intellectual Traditions In The Life Sciences: Molecular Biology And Biochemistry, Scott F. Gilbert

Biology Faculty Works

No abstract provided.


Height, Weight, And Fertility Among Participants Of The Third Harvard Growth Study, Eugenie Scott, Carl J. Bajema Sep 1982

Height, Weight, And Fertility Among Participants Of The Third Harvard Growth Study, Eugenie Scott, Carl J. Bajema

Peer Reviewed Publications

The relationship between weight, height, weigh/height2 and fertility is examined in 610 females and 621 males from a 1968 follow-up study of the Third Harvard Growth Study participants. These subjects were born between 1912 and 1918 in the USA. Their physical and mental growth were studies for up to 12 years while they attended public schools in Boston Massachusetts, area. Height is not significantly related to fertility in either females or males, but weight and weight/height2 is positively related to fertility in females (r = +.117 and + .100 respectively) and weight/height2 is positively related to fertility …


In Vivo Study Of The Effects Of Danazol On Cytoplasmic Receptors In The Female Rat, Deborah L. Spencer Aug 1982

In Vivo Study Of The Effects Of Danazol On Cytoplasmic Receptors In The Female Rat, Deborah L. Spencer

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 Deborah L. Spencer on August 26, 1982.


Characterization Of Danazol Binding To Specific Cytosol Receptors In Vitro, Gail Wright Russell Aug 1982

Characterization Of Danazol Binding To Specific Cytosol Receptors In Vitro, Gail Wright Russell

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 Gail Wright Russell on August 26, 1982.


A New Column Perfusion Technique Using Isolated Rat Adrenal Cells To Study Acth And Danazol, Diane H. Johnson Aug 1982

A New Column Perfusion Technique Using Isolated Rat Adrenal Cells To Study Acth And Danazol, Diane H. Johnson

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 Diane H. Johnson on August 15, 1982.


The Influence Of Livestock Feed Size On Feed Consumption By Starlings (Sturnus Vulgaris), Daniel Twedt Aug 1982

The Influence Of Livestock Feed Size On Feed Consumption By Starlings (Sturnus Vulgaris), Daniel Twedt

Masters Theses & Specialist Projects

Ground meal and 4 sizes of pelleted feeds (3/16, ¼, 3/8 and ½ inch diameters) were offered to captive Starlings (Sturnus vulgaris, Linnaeus) to determine the minimum feed size they were unable to consume in significant amounts. The ground meal, 3/8 and ½ inch diameter pellets substantially decreased feed consumption compared with 3/16 and ¼ inch diameter pellets. Additionally, ½ inch pellets were consumed substantially less than ground meal or 3/8 inch pellets. Supplemental feed was require to prevent mortality among Starlings offered only ½ inch pellets.

Two pellet sizes, the 3/16 inch pellet which was readily consumed by …


A Histopathological Study Of The Effect Of Ethylnitrosourea On Ha(Icr) Mice Testes, Mildred Rodriguez Aug 1982

A Histopathological Study Of The Effect Of Ethylnitrosourea On Ha(Icr) Mice Testes, Mildred Rodriguez

Masters Theses

Ethylnitrosourea (ENU) is very strongly mutagenic, carcinogenic and teratogenic in mice. In the present study ENU was used to induce germ cell damage in the mouse testis. Mice were given single injections of vehicle, 50, 100, or 200 milligrams of ENU per kilogram of body weight and killed at various times over a fifteen week period. Microscopic examination of the testes showed that extensive killing of spermatogonial cells and therefore maturation depletion had occurred in the seminiferous tubules. The histopathology was dose dependent and the testicular weight decreased with an increasing ENU concentration.


An Electrophoretic Comparison Of Gene Loci In Etheostoma Nigrum And Etheostoma Olmstedi From The James River Drainage, Virginia, Randall Keith Falls Aug 1982

An Electrophoretic Comparison Of Gene Loci In Etheostoma Nigrum And Etheostoma Olmstedi From The James River Drainage, Virginia, Randall Keith Falls

Master's Theses

As many as five different populations of Etheostoma nigrum and Etheostoma olmstedi have been identified in the James River drainage, Virginia. Genetic variation of these populations was analyzed with starch gel electrophoresis and revealed only three distinct populations. Nine loci encoding five enzyme systems and two loci encoding muscle proteins were examined in tissue homogenates. All populations were monomorphic with the exception of the esterase-3 (Est-3), phosphoglucomutase (Pgm-1) and phosphoglucose isomerase (Pgi) loci. Two alleles of Est-3 exhibited activity in the homozygous and heterozygous conditions. Pgm-1 occurred as two alleles with a high degree of heterozygosity (46% for E. nigrum …


Hindlimb Immobilization: Length-Tension And Contractile Properties Of Skeletal Muscle, Frank Arthur Witzmann, D. H. Kim, Robert H. Fitts Aug 1982

Hindlimb Immobilization: Length-Tension And Contractile Properties Of Skeletal Muscle, Frank Arthur Witzmann, D. H. Kim, Robert H. Fitts

Biological Sciences Faculty Research and Publications

The effect of hindlimb immobilization (IM) on the contractile properties of fast and slow skeletal muscle was studied in rats following various periods of IM ranging from 1 to 42 days; muscle atrophy, muscle, fiber, and sarcomere length, and the length-tension characteristics were determined after 42 days of IM. The slow-twitch soleus (SOL), the fast-twitch extensor digitorum longus (EDL), and the fast-twitch superficial region of the vastus lateralis (SVL) all showed rapid atrophy following the onset of IM, reaching a new reduced steady-state weight by day 21. After 42 days of IM the passive tension (g) and active twitch …