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Full-Text Articles in Biology

The Effect Of Aposematic Coloration On The Food Preference Of Aphelocoma Coerulescens, The Florida Scrub Jay, Mary Elizabeth Hill Jan 2003

The Effect Of Aposematic Coloration On The Food Preference Of Aphelocoma Coerulescens, The Florida Scrub Jay, Mary Elizabeth Hill

Theses and Dissertations

Aposematic coloration, commonly observed in noxious organisms, serves as a warning to predators to avoid attacking specific prey. This coloration is conspicuous in nature, with one of the most common examples being a red and black pattern. The plant Abrus precatorius exhibits this warning signal in its seeds, which resemble lady beetles and contain the concentrated toxin abrin. Aphelocoma coerulescens, an endemic and federally threatened bird in the state of Florida, shares a similar distribution with Abrus precatorius, making interaction between the two species possible. Using an edible model of the Abrus seed, this potential interaction was tested in Martin …


Studies On The Role Creb As A Mediator Of Neurotrophin-3 Actions In Oligodendrocytes, Jamie Richard Johnson Jan 2000

Studies On The Role Creb As A Mediator Of Neurotrophin-3 Actions In Oligodendrocytes, Jamie Richard Johnson

Theses and Dissertations

In the central nervous system (CNS), oligodendrocytes (OLGs) are the cells responsible for producing the myelin membrane which allows for the saltatory conduction of neuronal impulses. We have previously shown that CREB (cAMP response element binding protein), a transcription factor that belongs to a large family bZip (basic leucine zipper) proteins, could be a mediator of neuronal signals that, coupled to different signal transduction pathways, may play different regulatory roles at specific stages of oligodendrocyte development. We have found before that, in committed OLGs, CREB activation by phosphorylation can be triggered by β-adrenergic stimulation and appears to play a role …


A Computer Assisted Study Guide For Viral Hepatitis, April, 1999, Diana Hullihen Apr 1999

A Computer Assisted Study Guide For Viral Hepatitis, April, 1999, Diana Hullihen

Theses and Dissertations

The purpose of this project was to design a computer assisted program that would enhance the effectiveness of instruction in a clinical laboratory science program. Computer assisted instruction has been proven to be a beneficial and effective method of meeting educational objectives.

The topic of viral hepatitis is a complex and difficult one to teach. The instructor decided to supplement traditional lecture using computer assisted instruction. The goals and objectives of the lesson would be reinforced through this method as well as help the student to master the subject content.

The computer assisted study guide was designed to enhance the …


Obtaining And Sampling Of High Quality Energetic-Protein Mixtures (Pottages) Of Tuber-Cereal-Leguminous Bases In The Candelaria Area, Maria Lilian Maldonado Chavez Jan 1999

Obtaining And Sampling Of High Quality Energetic-Protein Mixtures (Pottages) Of Tuber-Cereal-Leguminous Bases In The Candelaria Area, Maria Lilian Maldonado Chavez

Theses and Dissertations

Specially designed foodstuffs destined for children of weaning age in the community of Candelaria were developed and evaluated biologically. These victuals had as bases combinations of tubers-cereals-legumes of high nutritional quality to be implemented in the home. Based on the availability of food and alimentary habits of the region, seven mixtures were formulated of triples and quadruples containing tubers (potato, oca, papaliza, and isano); cereals (rice, wheat, corn, and quinua); and legumes (tarwi, broad bean, and peanut). The cereal-leguminous proportion was maintained as one complement and the addition of the tubers. These mixes were subjected to biological tests, obtaining incremental …


The Effects Of Tactile/Kinesthetic Instructional Strategies In The Biology Classroom, Janice Batten Sees Apr 1998

The Effects Of Tactile/Kinesthetic Instructional Strategies In The Biology Classroom, Janice Batten Sees

Theses and Dissertations

The purpose of this study was to determine whether the addition of tactile/kinesthetic instruction to the biology classroom could significantly increase learning. Various kinds of tactile/kinesthetic lessons were taught to three experimental groups who also received visual and auditory instruction. These tactile/kinesthetic lessons included task cards, task puzzles, manipulatives, total body movement, and large floor games. The control group only received visual and auditory instruction. The subjects were 84 College Biology students from Buena Regional High School, a school in rural South Jersey. The classes varied in gender and race. The same instructor taught all classes and the length of …


Trophic Ecology Of Native And Introduced Catfishes In The Tidal James River, Virginia, Louis Fairfax Chandler Jan 1998

Trophic Ecology Of Native And Introduced Catfishes In The Tidal James River, Virginia, Louis Fairfax Chandler

Theses and Dissertations

Species introductions have been linked to the decline of native taxa, and in many cases have resulted in the elimination of native species in both terrestrial and aquatic systems throughout the United States. In aquatic systems, a particular threat is the introduction of large piscivorous fish that may alter the native fish community structure. For example, introductions of large ictalurids such as blue catfish, (lctalurus furcatus), and flathead catfish, (Pylodictus olivaris), into coastal Virginia rivers, including the James River twenty years ago have resulted in the establishment of these large, predatory fishes.

This study described the trophic ecology of four …


Determination Of Rates And Patterns Of Recombination At The Maize Red Color (R1) Locus, William R. Dietrich Jan 1998

Determination Of Rates And Patterns Of Recombination At The Maize Red Color (R1) Locus, William R. Dietrich

Theses and Dissertations

Homologous recombination has been studied in many plant and animal systems. In maize, most recombination occurs intragenically. The current study assessed the frequency and location of meiotic recombination at the maize red color (r1) gene. Three independent mutant (colorless seed) alleles derived from the colored seed allele, R-sc:124, were made heterozygous with the colored plant allele, r-r:n142. Each mutant resulted from the insertion of a Dissociation (Ds) transposable element into the 3' end of R-sc:124. In the presence of Activator (Ac), each Ds insertion allele (r-sc:mutables) produced spotted seeds and germinal reversion to fully colored seeds due to the vi …


Chlorophyll Biosynthesis In Kleptoplastid Symbioses, Robert Joseph Swatski Dec 1995

Chlorophyll Biosynthesis In Kleptoplastid Symbioses, Robert Joseph Swatski

Theses and Dissertations

The retention by ascoglossan sea slugs of photosynthetically functional algal chloroplasts (kleptoplastids) has been the subject of intense study over the past three decades. The question of whether kleptoplastids are capable of de novo chlorophyll biosynthesis was seemingly answered by Trench and Smith (1970) and Trench et al. (1973), who found no 14C uptake into chlorophylls in the ascoglossans, Elvsia viridis and E. crispata, after brief radioisotope incubations. However, Clark and Waugh (unpub.) demonstrated some 14C uptake into chlorophyll in CQStasiqlla ocellifera, a long-term kleptoplasad retainer, which promoted a re-analysis of these experiments. In order to prove the occurrence of …


Mitochondrial Dna Variation Within The Western-Clark's Grebe Complex (Podicipedidae: Aechmophorus), Bruce Alan Eichhorst May 1994

Mitochondrial Dna Variation Within The Western-Clark's Grebe Complex (Podicipedidae: Aechmophorus), Bruce Alan Eichhorst

Theses and Dissertations

The Western Grebe (Aechmophorus occidentalis) and Clark's Grebe (A. clarkii) are considered to be closely related .. Until recently, they were regarded as color phases of one species--the Western Grebe. I assessed mitochondrial DNA (mtDNA) variation within and between the Aechmophorus color phases. I also evaluated the plausibility of two vicariance models that have been. proposed to explain the evolution of the color phases. Grebes were collected from seven breeding sites, representing three geographic regions of the United States-Canada breeding range. Restriction-enzyme analysis of a total sample of 109 grebes was conducted. Estimates of nucleotide divergence ( dxy, da), nucleotide …


Small Mammal Demographics In North Dakota Conservation Reserve Program Plantings, Larry A. Lysne Aug 1991

Small Mammal Demographics In North Dakota Conservation Reserve Program Plantings, Larry A. Lysne

Theses and Dissertations

During the summers of 1989 and 1990, capture-recapture methods were used to de~ermine small mammal demographics and population dynamics in Conservation Reserve Program (CRP) plantings in north central North Dakota. Four age classes (1-4 years) of CRP plantings were sampled. Small mammal species diversity was low (H'=0.057-0.374). Eight species of small mammals were captured on CRP tracts, with deer mice (Peromyscus maniculatus) comprising 92% of all small mammals recorded. Largest deer mouse populations (64/ha .and 51/ha) occurred in late August and early September, 1990. Peak densities in 1990 were over twice as high as those of 1989. Home range sizes …


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.


A Nutritional And Morphological Study Of Two Cyanobacteria Free Azolla Ferns, Michael Paul Bonner Jan 1983

A Nutritional And Morphological Study Of Two Cyanobacteria Free Azolla Ferns, Michael Paul Bonner

Theses and Dissertations

The symbiotic association between the aquatic water fern Azolla and its symbiont, Anabaena azollae Straus. has been extensively studied in the past ten years. The cyanobacteria has received much of the attention due to its ability to fix atmospheric nitrogen while the fern free of the cyanobiont has been somewhat neglected. The purpose of this research was to determine the nutritional requirements of the cyanobacteria free (CBF) ferns and study the morphology of the leaves and branches of these CBF ferns.

Azolla filiculoides and Azolla pinnata were freed of the cyanobiont using the surface sterilization technique adopted from Duckett, et …


Multivariate Analyses Of Mid-Winter Fattening In Two Species Of Passerine Birds, Michael Harold Shelor Jan 1982

Multivariate Analyses Of Mid-Winter Fattening In Two Species Of Passerine Birds, Michael Harold Shelor

Theses and Dissertations

Although the adaptive significance of daily and seasonal fattening of birds has been studied by many investigators (see Odum, 1965; King, 1972; Blem, 1976a), surprisingly little is known about the interactions of proximate and ultimate environmental factors regulating avian lipid levels. An exception is the study by Evans (1969). He found that lipid levels in Yellow Buntings (Emberiza citrinella) were more closely correlated with long-term temperature averages than with temperatures of the day of capture, or the days preceding or following capture. This is an indication that temperature may be more important as an ultimate control of fattening, through natural …


An Interphysiographic Analysis Of Herb And Shrub Vegetation In Virginia Forests, Stephen James Binns Jan 1980

An Interphysiographic Analysis Of Herb And Shrub Vegetation In Virginia Forests, Stephen James Binns

Theses and Dissertations

Thirty upland deciduous stands were sampled from the mid-coastal Plain to the mid-Piedmont in New Kent, Hanover, and Louisa Counties. Density data for herb and shrub species were collected and soil samples were collected in each stand. A cluster analysis of the vegetation data was performed using Euclidean Distance and "furthest-neighbor" clustering. Four clusters of stands were identified. A cluster of six stands with Euonymus americanus as the dominant species was strongly related to the Coastal Plain, but the other clusters were not physiographically associated. Other important species in the analysis were Vaccinium vacillans, Gaylussacia baccata, and Mitchella repens.

The …


The Chronic Effects Of Estradiol Benzoate On Ventricular Myocardial Blood Flow In The Adult Female Rat, Stephen Maurice Ashe Jan 1980

The Chronic Effects Of Estradiol Benzoate On Ventricular Myocardial Blood Flow In The Adult Female Rat, Stephen Maurice Ashe

Theses and Dissertations

Clinical and experimental data suggest that humans and some animals are protected from acute myocardial infarction by estrogen. There has been much speculation of the exact role which estrogen plays in the circulation. The mechanism of this hormonally related protection is unclear.

In the present study the chronic effects of estradiol benzoate on coronary blood flow in adult female rats were studied. Female control rats, castrates and castrates receiving estrogen for a period of 16 weeks were used. In vivo tracer microsphere studies of myocardial blood flow allowed the quantification of the effects of estrogen on coronary circulation. Results of …


Characterization Of The Bursicon-Mediated Pathway For Membrane Permeability Enhancement In The American Cockroach, Periplaneta Americana, David Alan Compton Jan 1979

Characterization Of The Bursicon-Mediated Pathway For Membrane Permeability Enhancement In The American Cockroach, Periplaneta Americana, David Alan Compton

Theses and Dissertations

The presence of an adenyl cyclase system within the haemocyte of Periplaneta americana has been confirmed by previous investigations, with corresponding experiments using dibutyryl cyclic AMP to show enhancement of 14c-tyrosine uptake into the cuticle linked to stimulation of the sclerotization process.

In the present studies, American cockroaches held at depressed temperatures were treated with bursicon, revealing an increase in haemocyte cyclic AMP concentrations. The levels declined with progression of time, probably resulting from enzymatic hydrolysis.

When animals which had been held at room temperature were treated with bursicon, the levels of haemocyte cyclic AMP were lowered, with a declination …


Investigations Of Population Structure And Relative Abundance Of Year-Classes Of Buffalo Fishes, Ictiobus Spp., In Lake Sakakawea, North Dakota, David W. Willis May 1978

Investigations Of Population Structure And Relative Abundance Of Year-Classes Of Buffalo Fishes, Ictiobus Spp., In Lake Sakakawea, North Dakota, David W. Willis

Theses and Dissertations

This study was undertaken to investigate the population and abundance of year-classes of the buffalo fishes in Lake Sakakawea, North Dakota. Fish used in this study were obtained from Grasteit Dakota Fisheries, a commercial fishing operation headquartered in Newtown, North Dakota.

Only bigmouth buffalo (Ictiobus cyprinellus) and smallmouth buffalo (Ictiobus bubalus) were collected during this study; no black buffalo (Iciobus niger) were captured. The age and growth of these fish was found to be quite similar to that in other Missouri River mainstem reservoirs. The mean condition factor (K-TL) for the bigmouth was found to be 1.88 and for the …


Incorporation Of Phosphoproteins And Phenol-Bound Proteins Into The Cuticle Of Periplaneta Americana, Joseph Atchison Florence Iv Jan 1976

Incorporation Of Phosphoproteins And Phenol-Bound Proteins Into The Cuticle Of Periplaneta Americana, Joseph Atchison Florence Iv

Theses and Dissertations

The incorporation of phosphoproteins and phenol-bound proteins into the cuticle of Periplaneta americana was analyzed. Radioactive monosodium phosphate was injected into newly ecdysed cockroaches. Incorporation into haemolymph proteins as well as tanned cuticle was observed. Phosphoproteins were observed to be combined with the cuticle to a greater extent than monosodium phosphate. This suggests that phosphate is being incorporated into the cuticle more readily than monosodium phosphate. The relevance of these observations is discussed in light of phosphate being a possible crosslinking agent between chitin and cuticle protein.

Binding of dopamine metabolites to cuticle proteins was investigated. Specific metabolites studied were …


Distribution And Effects Of Bacterial Endotoxin, Anne Carter Adams Jan 1975

Distribution And Effects Of Bacterial Endotoxin, Anne Carter Adams

Theses and Dissertations

In this study the distribution and effects of bacterial endotoxin were examined. Adult male BALB/c and adult male DUB/ICR mice were used in all experiments. Endotoxic activity of a number of strains from three genera of bacteria, Pseudomonas, Bacteroides, and Listeria, was detected using vincristine-treated mice as sensitized indicators for endotoxin and resistance to purified endotoxin induced by pretreatment with selected bacteria. Also, the effect of bacterial endotoxin and endotoxin-like substances on the course of primary amebic meningoencephalitis in mice, caused by Naegleria fowleri, was assessed.


Food Habits Of The Game Fishes Of Lake Anna, Virginia, Thomas Kenneth Rohrer Jan 1975

Food Habits Of The Game Fishes Of Lake Anna, Virginia, Thomas Kenneth Rohrer

Theses and Dissertations

Beginning in May, 1973 and continuing through August, 1974 the food habits of several species of game fishes from Lake Anna, Virginia were investigated via gut content analysis. A variety of collecting methods were employed to secure specimens for examination and stomach contents were reported as percent frequency of occurrence. A total of one hundred and two collections were made yielding 287 largemouth bass, Micropterus salmoides (Lacépède); 166 chain pickerel, Esox; niger LeSueur; 53 bluegill, Lepomis macrochirus Rafinesque; 32 pumpkinseed, Lepomis gibbosus (Linnaeus); and 63 black crappie, Pomoxis nigromaculatus (LeSueur). It was found that M. salmoides and E. niger were …


The Benthic Communities Of The Eastern Rocky Shore Areas Of Goshen Bay, Utah Lake, Thomas Whitney Toole Aug 1974

The Benthic Communities Of The Eastern Rocky Shore Areas Of Goshen Bay, Utah Lake, Thomas Whitney Toole

Theses and Dissertations

Information about the benthic macroinvertebrate populations along the eastern shore of Goshen Bay, Utah Lake, Utah, can be used, in part, to determine future management of the lake. In the project herein reported, cement artificial substrate samplers were used to sample two types of substrate: rubble and compacted calcareous tufa. Monthly samples were obtained from each type of substrate from March 1972 to May 1973. An amphipod, Hyalela azteca and a chironomid, Dicrotendipes fumidus were the dominant organisms in numbers and tiomass. Amphipod numbers were dependent upon the amount of algal standing crop. Elimination of this area could affect the …


The Effect Of Aflatoxin B1 On Growth Rate And Iron Metabolism In Juvenile Mongolian Gerbils (Meriones Unguiculatus), William Stanley Hastings Jr. Jan 1973

The Effect Of Aflatoxin B1 On Growth Rate And Iron Metabolism In Juvenile Mongolian Gerbils (Meriones Unguiculatus), William Stanley Hastings Jr.

Theses and Dissertations

The metabolic secretions from Aspergillus flavus, aflatoxins. are often found as contaminants of agricultural products used for human and animal consumption. Aflatoxin B1 is the most toxic and carcinogenic of the aflatoxins. A reduction in weight gain has been observed when juvenile animals are fed aflatoxin B1 over an extended period of time. This reduction in weight gain may possibly result from an anemic condition induced by an alteration of iron absorption and/or distribution. The effect of chronic sublethal levels of this hepatocarcinogen on weight gain and the uptake and distribution of 59Fe++ were studied in this investigation.

An experimental …


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 Effects Of Channelization And Water Impoundment On The Macroinvertebrates In The Weber River, Summit County, Utah, Parley V. Winger Aug 1972

The Effects Of Channelization And Water Impoundment On The Macroinvertebrates In The Weber River, Summit County, Utah, Parley V. Winger

Theses and Dissertations

Macroinvertebrate populations in the Weber River, Summit County, Utah, were analyzed to determine what effects channelization resulting from Interstate-80 construction and water impoundment had on the standing crop, species diversity and species composition. Bottom samples were collected monthly from riffle areas in channeled and unchanneled sections and above Echo and Wanship Reservoirs. Macroinvertebrate populations in the channeled areas were similar in standing crop, species diversity and species composition to those in unchanged areas within six months following channelization. Species diversities were higher (d=4.1, 3.7) above the reservoirs than below (d=2.0). The reservoirs restricted the distribution of several species of macroinvertebrates. …


A Variation Of The Standard Steepest Ascent Search Procedure For Response Surface Experiments, George Whitfield Cobb Jan 1971

A Variation Of The Standard Steepest Ascent Search Procedure For Response Surface Experiments, George Whitfield Cobb

Theses and Dissertations

The results of this chapter lead to a modification of the standard stopping rule which breathes new life into the method of steepest ascent, but which is unfortunately not sufficient to effect a total resuscitation. As expected, there is no uniformly optimum stopping rule, nor even a uniformly best test statistic; both the optimum statistic and the optimum test level depend on the model parameters y1 and y2. One can, however, adopt a compromise rule which works reasonably well for all parameter combinations by testing at the 25% level with the statistic zn = 1/2(yn -yn-2). In many cases the …


Nesting And Brooding Characteristics Of Sharp-Tailed Grouse (Pedioecetes Phasianellus Jamesi Lincoln) In Southwestern North Dakota, Carter Drew Christenson Dec 1970

Nesting And Brooding Characteristics Of Sharp-Tailed Grouse (Pedioecetes Phasianellus Jamesi Lincoln) In Southwestern North Dakota, Carter Drew Christenson

Theses and Dissertations

A study of the nesting and brood habitat preferences of sharp-tailed grouse (Pedioecetes phasianellus jamesi Lincoln) was conducted in southwestern North Dakota during the reproductive seasons of 1969 and 1970. Radio telemetry was used to monitor the spring and summer activities of seventeen sharp-tail hens. Eight brooding hens were semi-continuously radio-tracked for movement and cover selection. A quantitative and qualitative analysis of seventeen nests and eight renests was made to determine the preferred nesting cover and the effects of intensive grazing upon it .. Nests were established either in non-use areas or in areas of light to moderate grazing. These …


Aquatic Phycomycetes Of Lily Lake, Hugh Macmillan Rooney May 1967

Aquatic Phycomycetes Of Lily Lake, Hugh Macmillan Rooney

Theses and Dissertations

Lily Lake, a subalpine lake in the Wasatch National Forest Tl5, R9E, S31, of the Uinta Mountain Region, Utah, is located about one-half mile west of Trial Lake at an elevation of 10,000 feet. This Lake, which is one of the acidic, cold, lentic bogs characteristic of this area, has been selected for a taxonomic and seasonal distribution study of acquatic phycomycetes. This study is a beginning to our knowledge of the role of the fungi in the hydrobiology of Lily Lake and will supply the first information on record of the water molds of this area. The study identifies …


Ecology Of Summer Aquatic Invertebrate Populations In A Marsh Area Of Utah Lake, David A. White Aug 1963

Ecology Of Summer Aquatic Invertebrate Populations In A Marsh Area Of Utah Lake, David A. White

Theses and Dissertations

Mud Lake marsh lies east of Utah Lake between the cities of Provo and Springville in Utah County. Since 1936 it has become a polluted, odiferous, silted area. A study was conducted on the aquatic invertebrates during the summer of 1962 (June 19 to September 20). An .01 meter2 bottom sampler was used at 30 random stations. Each station was sampled once a week. Water depth, mud, water and air temperatures were taken at each station. Dissolved oxygen (Winkler method) and ion resistance (Wheatstone bridge) were taken each day. The aquatic invertebrate community consisted of benthic (Diptera, Oligochaeta, Nematoda), interphashic …


Studies On The Periodicity Of Certain Plankton Species Of Salem Lake, Gene A. Pratt Aug 1957

Studies On The Periodicity Of Certain Plankton Species Of Salem Lake, Gene A. Pratt

Theses and Dissertations

Plankton samples were taken periodically from one station in Salem Lake from the fall of 1955 through the winter of 1957. Other data including the pH, dissolved oxygen content, turbidity, brightness of day, temperature, and time of day were recorded at the time of each collection. The plankton samples were centrifuged and preserved in a 4% formalin solution. They were later examined microscopically, and density, percent density, and percent frequency calculations were made from them for ten selected species and for the five phyla which they represent.