Digital Commons Network^™

Description Of Tadpoles Of Three Species Of Scinax (Anura: Hylidae), Rafael O. De Sá, Rocjard Wassersig, Arturo I. Kehr

Biology Faculty Publications

Larval morphological characteristics have been used to cluster species of Scinax in seven species groups and to support the monophyly of some of these groups. However, our present knowledge of Scinax tadpoles is incomplete; currently, tadpoles of only 21 of the approximately 80 recognized species have been described. Herein, we describe and illustrate the external morphology and oral disc characteristics of larval Scinax berthae, S. nebulosa, and S. boesemani. The presence of a "labial arm" supporting the P3 tooth row in S. boesemani, and its absence from S. nebulosa, is discussed in the light of our limited knowledge of tadpoles …

Law And Biology: Toward An Integrated Model Of Human Behavior, Owen D. Jones

Vanderbilt Law School Faculty Publications

As first year law students unhappily discover, the meaning of "law" is frustratingly protean, shifting by usage and user. Depending on whom you ask, law is a system of rules, a body of precedents, a legislative enactment, a collection of norms, a process by which social goals are pursued, or some dynamic mixture of these. Law's principal purpose is to define and protect individual rights, to ensure public order, to resolve disputes, to redistribute wealth, to dispense justice, to prevent or compensate for injury, to optimize economic efficiency, or perhaps to do something else. And yet one thing is irreducibly …

The Effects Of Adrenergic And Cholinergic Stimulation On Skin Gland Secretions In The Dwarf African Frog Hymenochirus Curtipes, Daniel H. Gong

University of the Pacific Theses and Dissertations

Many studies have been done on the neural control of serous gland secretion in the skin of frogs and newts. However, no studies have been published on the effects of adrenergic and cholinergic neurotransmitters on the sexually dimorphic breeding glands of male frogs. The present study examined the effects of neurotransmitters on the serous and breeding glands of Hymenochirus curtipes. Explants of dorsal skin and postaxial skin (containing whole breeding glands) were incubated in vitro with epinephrine, norepinephrine or acetylcholine for 30 minutes. The explants were then preserved and examined histologically for signs of secretion. The area and perimeter of …

The Roles Of Harsh And Fluctuating Conditions In The Dynamics Of Cological Communities, P Chesson, Nancy J. Huntly

Biology Faculty Publications

Harsh conditions (e.g., mortality and stress) reduce population growth rates directly; secondarily, they may reduce the intensity of interactions between organisms. Near-exclusive focus on the secondary effect of these forms of harshness has led ecologists to believe that they reduce the importance of ecological interactions, such as competition, and favor coexistence of even ecologically very similar species. By examining both the costs and the benefits, we show that harshness alone does not lessen the importance of species interactions or limit their role in community structure. Species coexistence requires niche differences, and harshness does not in itself make coexistence more likely. …

Investigation Of Transactivation Of The Human C-Myc Gene By Herpes Simplex Virus Type 1, Xian Wu

Dissertations and Theses

The purpose of this investigation was to identify the regulatory elements involved in the transactivation of the human c-myc gene by herpes simplex virus type-1 (HSV-1). This study mainly focused on a major c-myc promoter P₂ (Fig. 1). Transient expression assays were carried out with a reporter plasmid, that contained either a wild type (+66wt c-myc) or mutant (+66 mt E2F, +66mt CT -I₂) c-myc promoter fused to the chloramphenicol acetyltransferase (CAT) gene, cotransfected with effector plasmids that contained the HSV-1 immediate early (IE) genes ( encoding IE proteins, ICP4, ICP0, ICP27). The transient expression assays revealed …

Saccharomyces Cerevisiae-Produced Recombinant Pfs230: A Malaria Transmission-Blocking Vaccine Candidate, Kathryn M. Glynn

Master's Theses

No abstract provided.

Nest Box Use, Reproductive Success, And Nestling Growth Of American Kestrels (Falco Sparverius) Nesting Along The Coastal Plain Of Georgia, Walter Roy Shuford

College of Graduate Studies: Theses & Dissertations (1964–2006)

In an attempt to increase breeding populations of American Kestrels (Falco sparverius) in Georgia, 402 nest boxes were erected in the Coastal Plain of Georgia beginning in 1994 through the spring of 1996. Nest box occupancy averaged 8% in 1996 and 9.7% in 1997, two fold the average in 1995. Occupancy at Fort Gordon military base averaged 27.5% (28 of 102) in 1996 and 29 4% (30 of 102) in 1997 Nest box use in all other areas averaged 13% (4 of 300) in 1996 and increased to 3% (9 of 300) in 1997. Clutch sizes for nests …

Small Miracles: Propagation Efforts Using Plants In The Family Hamamelidaceae, Martha Sasser Joiner

College of Graduate Studies: Theses & Dissertations (1964–2006)

Attempts were made to propagate five species in the family Hamamelidaceae by softwood cuttings or seeds. Local populations of witch-hazel Hamamelis virginiana L. and sweetgum Liquidambar styraciflua L. supplied cuttings and seeds of these native American species. Cultivated plants of dwarf witch-alder Fothergilla gardenii Murray were used initially for cuttings. Later, three native populations of this species were located and cuttings were obtained from them. Also, for seed propagation studies, seeds of F. gardenii were obtained from the North Carolina Botanical Garden and seeds were obtained from cultivated plants of two Asian species, winter hazel Corylopsis sinensis Hemsley and Chinese …

Arterial Wall Hypertrophy And Pdgf-A Expression In One-Kidney, One-Clip Hypertension And Angiotensin Ii Infusion Are Mediated By Elevated Arterial Pressure, Sheri Blair Parker

Theses and Dissertations in Biomedical Sciences

These studies were designed to characterize the relative roles of angiotensin II (ANG II) and pressure in the structural alterations that occur in experimental hypertension. Two separate studies were performed in order to differentiate these two mechanisms. First, male Wistar rats were subjected to one-kidney, one-clip (1K1C) hypertension or sham operation. Losartan, an AT1 receptor antagonist, was administered chronically to half of each surgical group beginning one day before the operation and continued until the end of the study. In a second experiment, rats were implanted with osmopumps delivering either ANG II or saline. To maintain pressure in the normotensive …

Understanding Of Wetlands As Expressed By Selected Community Leaders, Donald Nathan Bardole

Dissertations and Theses @ UNI

This study focuses on ascertaining the understanding of wetlands by selected community and state leaders and determining the source of that knowledge. Because of the subjects' positions of influence, this information may become an important element in understanding the decisions made by those community and state leaders. An interview survey was designed and piloted for this study. Community and state leadership positions were first delineated and then individuals selected from each category. The subjects varied considerably in their knowledge of wetlands, showed the presence of professional expediency, and agreed that regulation in some form is necessary. The wetlands knowledge held …

Ecomorphology Of Peromyscus In Iowa, Frederick Dramani Biga

Dissertations and Theses @ UNI

Deer mice (Peromyscus maniculatus bairdii) and white-footed mice (Peromyscus /eucopus noveboracensis) were collected from weedy and prairie habitats of Black Hawk County, and white-footed mice were collected from forested areas of Hardin County, Iowa. Twenty-three external and cranial characters were measured from 125 deer mice and 72 white-footed mice. Analysis of means by t-tests showed significant sexual dimorphism in deer mice in four cranial characters; palatine width at 3rd molar, width of foramen magnum, width of 3rd molar, and width of the incisor. Sexual dimorphism was also found in white-footed mice in three external and one cranial character: total length, …

Role Of Calcium And Other Cations On Contractile Vacuole Activity Of Tetrahymena Thermophila, Robert William Bird

Dissertations and Theses @ UNI

The contractile vacuole (CV) of Tetrahymena removes fluids from the cell and maintains cellular integrity. Although many studies have been done, it is not fully understood what controls its function. Therefore, this study sought to further elucidate an understanding of what controls the activity of the CV. The effect of calcium on CV activity was studied. Twenty-four hour cultures of Tetrahymena were centrifuged, washed in an experimental solution and isolated. Single cells were measured and analyzed using computer video imaging and analysis programs. Compared to control cells, cells treated with calcium have statistically significant differences (P < 0.00001) in the following parameters: smaller overall cell volume, CV volume, and the interval between contractions. Calcium has an effect on CV activity. Increases in calcium result in decreases in cell volume and CV volume. Cadmium treated cells differed (P < 0.00001) from control cells in cell volume, CV volume, kinetics (slope) of contraction, and the interval between contractions. Increases in cadmium, relative to calcium, result in increased cell and CV volumes. Taken together, these results indicate that the control of CV activity in Tetrahymena is through stretch-activated ion selective calcium channels.

Fat Storing Patterns Of Migrating Sharp-Shinned Hawks, David John Conrads

Dissertations and Theses @ UNI

Many species of birds store fat as the primary fuel for migration. Although this is well-documented in many avian families, little is known about fat-storing patterns of migrating birds of prey. Pre-migratory fattening has been recorded in falcons and presumed in buteos. However, fat-storing patterns in migrating Accipiter hawks has not been documented. This study examined the fat-storing patterns of Sharp-shinned Hawks (A. striatus) during a portion of its fall migration. During Sharp-shinned Hawk migration three possible fat-storing patterns are predicted: I) fat deposition increases, 2) fat deposition is maintained, or 3) fat deposition decreases. To determine which strategy is …

Macrophyte-Macroinvertebrate Interactions In A Lentic Ecosystem And The Effect Of Fluridone Treatment To Control Myriophyllum Spicatum L., Gregory J. Moeller

Dissertations and Theses @ UNI

Myriophyllum spicatum L. is an exotic macrophyte that can become pestiferous in lentic ecosystems. Two field studies were conducted to investigate: 1) epiphytic macroinvertebrates associated with M. spicatum and native macrophytes; and 2) epiphytic macroinvertebrate community response to fluridone treatment for M. spicatum control.

In the first study evaluating epiphytic macroinvertebrates associated with M. spicatum and native macrophytes, triplicate samples were collected at three sites in both Auburn and Zumbra Lakes, Minnesota, USA. One site in each lake contained primarily M. spicatum, the second site contained M. spicatum and native vegetation, and the third site was dominated by native …

In Situ Hybridization, In Situ Transcription, And In Situ Polymerase Chain Reaction, L. E. De Bault, J. Gu

Scanning Microscopy

In situ hybridization, in situ transcription, and in situ polymerase chain reaction (PCR) are techniques used to detect DNA and RNA sequences within a cell or tissue structure. These three in situ methodologies employ the principles of recombinant DNA to form double-stranded hybrids of DNA-DNA, DNA-RNA, or RNA-RNA. The essence of in situ hybridization (ISH) is the hybridization of a labeled probe to a complementary target sequence, whereas in situ transcription (IST) is the synthesis of complementary DNA incorporating a label directly on the target DNA or RNA within a cell or tissue. In the case of in situ PCR …

Aspects Of Cryofixation And Cryosectioning For The Observation Of Bulk Biological Samples In The Hydrated State By Cryoelectron Microscopy, K. Richter

Scanning Microscopy

Cryoelectron microscopy allows the observation of hydrated samples at high spatial resolution, and it would be of great interest in biology to apply this method to cells and tissues. However, because of technical problems, the cryo-observation of frozen hydrated ultrathin sections of bulk material has not become an established method. The major limitations are due to the difficulty of achieving the vitrification of such material, and the structural deformation caused by ultrathin sectioning: 1. The vitrification of cells in a physiological environment requires high-pressure freezing. However, new results suggest that the pressure may alter the ultrastructure of the sample. 2. …

Evaluation Of The Success Of Constructed Wetlands In The Cave Run Lake Watershed, April Diane Haight

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by April Diane Haight on December 10, 1996.

Electro-Optical Imaging Of F-Actin And Endoplasmic Reticulum In Living And Fixed Plant Cells, Nina Stromgren Allen, Marty N. Bennett

Scanning Microscopy

Confocal and video micrographs of living and fixed alfalfa roots, onion epithelial and pear pollen cells illustrate the architecture of the cytoskeleton and endoplasmic reticulum in plant cells. Fixation of plant tissues to preserve cytoplasmic structure poses special problems. When possible, emphasis should be placed on the imaging of structures in stained living cells over time. The early events that occur when Nod factors or bacteria elicit nodule formation in alfalfa roots will illustrate several approaches to plant cell fixation, staining and imaging. The first observable events after Nod factor stimulation occur in root hairs and are changes in rates …

Chemical Communication In House Mice (Mus Musculus): Can They Recognize Gender From The Anogenital, Harderian Gland Or Mouth/Nose Odor?, Dawn Michele Andrews

Dissertations and Theses

Identifying the sensory systems animals employ to communicate chemically and the function of the chemical signals facilitates further understanding of chemical communication. Increased knowledge of how animals use the olfactory and vomeronasal systems in order to interpret the meaning of body odors will aid in developing a more detailed organization of chemosensory pathways. The message that each body odor contains can change from species to species.

The purpose of this thesis was to study three previously untested body odors in house mice (M. musculus) for their role in gender recognition of conspecifics. These odors are the anogenital (feces, …

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.

The Effects Of Benzo(A)Pyrene And Dimethylbenzanthracene On Cultured Porcine Aortic Endothelial Function, Michelle Lynn Kagey

Masters Theses

Polycyclic aromatic hydrocarbons are environmental contaminants which have been shown to initiate and promote atherosclerosis and carcinogenesis in various animal species. These findings have been based primarily on the increase in incidence and size of smooth muscle cell tumors in these animals were exposed to benzo(a)pyrene (BaP) or dimethylbenzanthracene (DMBA). The endothelium has also been identified as an important mediator in vascular disease and atherogenesis, although the endothelial response to these PAHs has not been investigated. Thus, the focus of this study was on characterization of the endothelial response to BaP and DMBA. Concentration/response relationships for these chemicals were examined, …

Biology: What One Needs To Know, Ursula Goodenough

Biology Faculty Research

Biology on this planet represents an astonishing experiment in carbon-based chemistry which, over billions of years, has generated billions of species adapted to countless major and minor fluctuations in ecological circumstances. In one sense there is no way to generalize about biology. While biological activities can all be ultimately explained by physical laws (like everything else in the universe), it is the emergent intensely particular properties of organisms that most interest us. This essay represents an attempt to describe some of the more prominent patterns that emerge from the sea of biological particularities, patterns that present many opportunities for religious …

Expression Of Α4Β1 Integrin On Tissue Eosinophils In The August Rat, John C. Phipps

Masters Theses

The integrin α4β1 is expressed on a wide variety of peripheral leukocytes, and functions in recruitment of these cells to sites of inflammaiton. We infected august (AUG) rats with the helminth parasite Nippostrongylus brasiliensis and later used leukocytes from the peritoneum of the sensitized animals and antibodies against α4β1 integrin to localize that adhesion molecule on the cell surfaces after antigen challenge. We found that after antigen challenge, eosinophils, monocytes, and small lymphocytes, but not mast cells, expressed α4β1 integrin if the animals had been previously infected, but cells from uninfected animals did not show expression of this molecule. Our …

Effect Of Nesting Structure Density On Clutch Success Of Canada Geese, Branta Canadensis, Nesting In Constructed Wetlands In The Cave Run Lake, Kentucky, Area, Teresa L. Caudill

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Teresa L. Caudill on November 26, 1996.

Genetic And Social Control Of Male Maturation In Phallichthys Quadripunctatus (Pisces: Poeciliidae), Gita R. Kolluru, David N. Reznick

Biological Sciences

Age and size at maturity can have significant fitness consequences. Selection often favors early-maturing individuals because of their higher survival to maturity and greater relative contribution to population growth rate, but it may also favor delayed maturation if fitness increases with age or size at maturity. Males of several poeciliid fishes exhibit variation in age and size at maturity primarily controlled by a sex-linked gene called the P-locus. Wild-caught Phallichthys quadripunctatus males show a bimodal size distribution, which is often associated with a P-locus polymorphism in other poeciliids. We conducted two experiments to evaluate the inheritance of male age and …

Trade-Offs, Food Web Structure, And The Coexistence Of Habitat Specialists And Generalists, Mark A. Mcpeek

Dartmouth Scholarship

Species differ greatly in the breadth of their environmental distributions. Within the same collection of habitats, some species occur in many habitats, while others are only able to exist in one of a few. Trade-offs in the abilities of species to perform in various ecological interactions are important both to facilitating species coexistence within a habitat and to limiting the distributions of species among habitats. In this article I use a food web model to explore how in the same collection of habitats some species may be limited by trade-offs to occupying only one habitat, while other species may face …

A Re-Evaluation Of Hotspot Settlement In Lekking Sage Grouse, Robert M. Gibson

School of Biological Sciences: Faculty Publications

Recent analyses of avian leks have come to conflicting conclusions concerning the role of male settlement on female traffic hotspots. This issue was re-examined in the sage grouse, Centrocercus urophasianus, using data on prenesting movements of radio-tagged females and the dispersion of lekking males collected during a 10-year field study. As expected with hotspot settlement, leks were preferentially located in areas through which females traveled between wintering and nesting ranges before mating. In addition, the distribution of males among leks was related proximately to variation in numbers of females visiting each lek during the mating period and ultimately to …

Atomic Force Microscopy Of Humic Acids, A. Ikai, R. Osterberg

Scanning Microscopy

Atomic force microscopic (AFM) images of humic acids show discrete, globular particles, where particles of the order of magnitude 100 to 300 nm dominate the image fields; the humic acids had been grown to a steady state at pH 5.0. The AFM data are consistent with our previously reported small-angle neutron scattering (SANS) study done under similar conditions. In further agreement, the cluster-cluster interactions shown in our previous SANS study may have their counterparts in closely interacting particles appearing as twin particles in the AFM images.

Preparation Of Cultured Smooth Muscle Cells From Human Myometrium For X-Ray Microanalysis, Jarin Hongpaisan, Godfried M. Roomans

Scanning Microscopy

Methodological aspects of the use of X-ray microanalysis in physiological and pharmacological experiments on cultured myometrial cells were investigated. Cultured human myometrial cells were grown from biopsies after detaching the fibroblasts. Of the cultured cells, 95-98% showed desmin-like immunoreactivity. Transmission electron microscopy showed that subcultured cells were different from myometrial cells in situ. The effects of washing the cells to remove external salt-rich medium were investigated. All solutions removed the external medium, resulting in lower concentrations of Na and Cl. In the cells washed with 0.3 M mannitol, most of the elemental concentrations were significantly lower than in their …

Morphological And Chemical Properties Of Plastic Residues In Composts, Charles R. Krause, Leona E. Horst, Harry A. J. Hoitink

Scanning Microscopy

The relative quantity of plastic film residues and other man-made materials in composts prepared from municipal solid wastes (MSW), biosolids, yard wastes, and pine bark was evaluated utilizing light and scanning electron microscopy equipped with energy dispersive X-ray analyzer. MSW composts screened through a 4 mm screen contained significant but highly variable quantities of plastic film residues and other man-made materials that escaped detection with the unaided eye. The other composts were free of such particles. We conclude that the database for evaluation of man-made materials in MSW composts is inadequate and must be developed further.