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Atrial Natriuretic Factor In Meriones Unguiculatus, The Mongolian Gerbil, Kyriakos Tarasidis

Master's Theses

The basis for the great osmoregulatory ability in Meriones unguiculatus, the Mongolian gerbil, has been studied previously, but as yet no clear mechanism has been determined. The present study investigated the level of cardiac atrial natriuretic factor (ANF) under high and low sodium stress. In addition, cardiac ANF values for the Mongolian gerbil were compared with another desert mammal (Mesocricetus auratus, the Syrian golden hamster) and a non-desert mammal, (Rattus norvegicus, the white rat). ANF was found to exist in the hear atria of the Mongolian gerbil at a level of 388±66 µg ANF/g tissue. High and low sodium stress …

Factors Affecting Parental Investment Strategies In Male Waterbugs, Scott Kight

Department of Biology Faculty Scholarship and Creative Works

Male giant waterbugs (Belostoma flumineum Say) brood eggs oviposited on their dorsi by conspecific females. Preliminary observations indicate that viable egg pads are sometimes discarded before hatching. Theory predicts that such behavior should occur only if costs incurred by brooding exceed benefits of hatching the egg pad. The amount of paternal investment per pad should be similar for both large and small pad sizes, but as egg pads become smaller, investment per egg increases. Thus, smaller pads should be more likely to be discarded unhatched than larger ones. Similarly, egg pads containing inviable eggs should also be more frequently …

Drop-Box Technique For Quantitative Sampling Of Macrofauna And Aquatic Plants At Restored And Natural Wetlands, J. Douglas Oliver, Andrew J. Leslie, William M. Bartodziej

Faculty Publications and Presentations

No abstract provided.

Nesting Ecology Of The Cooper’S Hawk In Iowa, David John Conrads

Dissertations and Theses @ UNI

The Cooper's Hawk (Accipiter cooperii) was once a common nesting raptor in Iowa. Habitat destruction, pesticides and their residues, and human persecution have recently contributed to the decline of this species throughout its range. It is listed as an endangered species in Iowa by the Iowa Department of Natural Resources. In 1988 and 1989, historic nesting areas were searched for nesting Cooper's Hawks. Areas with birds displaying breeding behavior were also searched for nests. Nests were observed to determine nesting success and productivity. Habitat characteristics were measured for 33 nests found between 1985 and 1989. Macrohabitat and microhabitat were defined …

Activator-Inhibitor Control Of Tissue Growth, John A. Adam

Mathematics & Statistics Faculty Publications

This note develops a simple model for the competition between activator and inhibitor control mechanisms in one-dimensional tissue growth. The pedagogic usefulness of such a model is that it is easily accessible to undergraduate applied mathematicians and is suggestive of behavior known to occur in more realistic biological systems (e.g., some types of cancer). The limitations of the model are obvious and can provide a basis for discussion of the applicability of complementary levels of description in mathematical modeling.

Seasonal Phytoplankton Assemblages Associated With The Chesapeake Bay Plume, Harold G. Marshall

Biological Sciences Faculty Publications

Waters associated with the Chesapeake Bay plume were highly variable, unstable, and subject to the influence of flow patterns into and out of the Bay. Seasonal phytoplankton assemblages were identified for this region, with the phytoplankton development similar to the seasonal spring-fall growth maxima over the shelf, yet influenced by the multi-pulsed patterns often noted in the lower Bay. Major dominants included species common to both the shelf and lower Chesapeake Bay.

New And Corrected Floristic Records For Nebraska, Steven B. Rolfsmeier, Robert B. Kaul, David M. Sutherland

Biology Faculty Publications

Nineteen species (including eight Eurasian ones) are newly recorded for Nebraska: Alopecurus arundinaceus, Amaranthus californicus, Asclepias asperula, A purpurascens, Cardamine {lexuosa*, Centaurea diffusa, Dipsacus laciniatus, Eriochloa villosa, Euclidium syriacum, Gentiana alba, Geranium viscosissimum, Geum vernum, Goodyera oblongifolia, Haplopappus multicaulis, Heterotheca latifolia, Lathyrus tuberosus, Polygonum douglasii, Scirpus saximontanus, Veronica biloba. Twenty-one others are shown to be more widespread in Nebraska than previously known, one has a more restricted range than previously reported, two (Scirpus smithii, S. torreyi) are deleted from the flora based upon corrected identifications, and the status of some rarely-collected species is updated. Thirty-two additions, two …

Structural And Functional Studies Of The Tryptophan Operon Of Bacillus Pumilus, Miriam V. Rivas

Dissertations, Theses, and Capstone Projects

The nucleotide sequence of the trpE, trpD, and 5’trpC genes of the Bacillus pumilus tryptophan operon was determined for a comparative evaluation. DNA comparisons to the tryptophan operon of a related species, Bacillus subtilis, showed 66% base homology. The overlapping of translational start and stop signals indicate that, similar to Escherichia coli, the trpE, trpD, and trpC genes of the B.pumilus trp operon are translationally coupled. The values for amino acid identity between the two Bacilli showed 68, 62, and 65% for trpE, trpD and 5’trpC genes, respectively. Charge related residues …

Specimen Catalog, Robert W. Dickerman

Division of Mammals - Field Notes and Catalogs

No abstract provided.

Intracellular Ph Decreases During Entry Into Estivation In The Land Snail Oreohelix, Bernard Rees

Biological Sciences Faculty Publications

No abstract provided.

Genetic Analysis Of Posterior Bithorax-Complex Mutants In Drosophila Melanogaster, Chunni Duan

Retrospective Theses and Dissertations

No abstract provided.

Mitochondrial Malate Dehydrogenase From Corn, Marianne K. Hayes, Michael Hans Luethy, Thomas Elthon

School of Biological Sciences: Faculty Publications

A method to fractionate com (Zea mays L. B73) mitochondria into soluble proteins, high molecular weight soluble proteins, and membrane proteins was developed. These fractions were analyzed by both sodium dodecyl sulfate-polyacrylamide gel electrophoresis and assays of mitochondrial enzyme activities. The Krebs cycle enzymes were enriched in the soluble fraction. Malate dehydrogenase has been purified from the soluble fraction by a two-step fast protein liquid chromatography method. Six different malate dehydrogenase peaks were obtained from the Mono 0 column. These peaks were individually purified using a Phenyl Superose column. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified peaks showed that …

Potential Impacts Of Biomass Production In The United States On Biological Diversity, James H. Cook, Jan Beyea, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Biomass could be a renewable source of energy and chemicals that would not add CO₂ to the atmosphere. It will become economically competitive as its cost decreases relative to energy costs, and biotechnology is expected to accelerate this trend by increasing biomass productivity. Pressure to slow global warming may also make biomass more attractive. Substantial dependence on biomass would entail massive changes in land use, risking serious reductions in biodiversity through destruction of habitat for native species. Forests could be managed and harvested more intensively, and virtually all arable land unsuitable for high-value agriculture or silviculture might be used …

Littoral And Limnetic Zooplankton Communities In Lake Mead, Nevada-Arizona, Usa, Patrick J. Sollberger, Larry J. Paulson

Publications (WR)

Zooplankton were collected from adjacent littoral and limnetic sites in Lake Mead, Nevada-Arizona, USA. Limnetic species dominated both littoral and limnetic zooplankton communities; littoral species rarely exceeded 2% of monthly total zooplankton densities. Low species richness of littoral taxa and high similarity in species composition between littoral and limnetic habitats appeared to result from uniform horizontal physical and chemical environments, due to horizontal mixing, and from the absence aquatic macrophytes. Significant differences in spatial distribution occurred in phytoplankton biomass, total zooplankton density, and fish "abundances; highest concentrations of these factors occurred nearest an inflow high in nutrients and progressively declined …

"Metacercarial Load Of Fresh-Water Crabs Liberonautes Latidactylus In An Endemic Paragonimiasis Focus In Liberia, West Africa" , R Sachs, Neil Cumberlidge

Journal Articles

No abstract provided.

" Sudanonautes Kagoroensis, A New Species Of Fresh-Water Crab From Nigeria" , Neil Cumberlidge

Journal Articles

No abstract provided.

Multivariate Analysis Of The Carex Brevior Group In Iowa, Scott C. Zager

Dissertations and Theses @ UNI

In Iowa, the most troublesome sedges to identify are Carex brevior, C. festucacea, C. molesta, C. normalis, C. tenera, and C. tenera var. echinodes. These taxa form the C. brevior group--part of an even larger aggregate of species associated with C. straminea. Their morphological features are indistinct and intergrade into one another. Botanists have had difficulty classifying members of this aggregate for nearly 200 years. Some authors have viewed the taxa as separate species, others as polymorphic forms of a single species. Much of the contention has centered upon the variation of taxonomic characters used to delimit and distinguish species. …

Phenology And Bionomics Of Culicoides (Diptera: Ceratopogonidae) In Glynn County, Georgia, Lisa M. Westberry

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

Seasonal abundance and population densities of Culicoides species from sites in Glynn County, Georgia were surveyed using 15 New Jersey light traps during a 9-month period from April-December 1990. Environmental effects on the abundances were also analyzed. The three primary species present were: Culicoides furens (Poey), C. hollensis Mellander & Brues, and C. melleus (Coguillett). C. furens were collected year round, but predominantly during the summer. C. hollensis had a bimodal abundance (spring and fall) . C. melleus also had a bimodal abundance (late summer and fall).

Larval habitats of the primary species were identified …

Structure And Function Of Human Alphoid Dna, Darryl S. Schlegel

Master's Theses

No abstract provided.

Woody Plants Of The Lower Rio Grande Valley, Texas, Robert I. Lonard, James H. Everitt, Frank W. Judd

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

Description of Common Vegetation of Lower Rio Grande Valley.

The Effects Of Glutathione On Human Keratinocyte, Manisha N. Trivedi

Theses and Dissertations in Biomedical Sciences

Cultured human keratinocytes were grown in vitro to assess the effects of glutathione, a thiol, on human keratinocyte proliferation. Single keratinocytes were harvested from newborn (greater than 5 days old) foreskin and were grown in culture flasks such that experiments could be performed in approximately 2 to 3 weeks. In order to evaluate the effects of glutathione (GSH) on keratinocyte growth, experiments were performed to determine the growth curve, plating efficiency, and incorporation of radiolabelled thymidine. Growth studies, performed with different concentrations of glutathione, revealed that 0.065 μM was the most effective concentration when compared to control cell cultures, and …

A Cytochemical Scanning Electron Microscopy Study Of Non-Specific Acid Esterase And Acid Phosphatase Activities In Human Peripheral Blood Lymphocytes, A. Campos, E. Fernández-Segura, J. M. García-López

Scanning Microscopy

We analyzed the distribution patterns of nonspecific acid esterase and acid phosphatase activities with cytochemistry-scanning electron microscopy in backscattered and secondary electron imaging modes in isolated normal human peripheral blood lymphocytes . The analysis of non-specific acid esterase activity in the backscattered electron imaging mode showed, in some cells, focal distribution with a well-defined, homogenous deposit. Two patterns of acid phosphatase activity were evident with the backscattered electron imaging mode, i.e., focal and granular. Peripheral blood lymphocytes showing focal activity of both enzymes presented a smooth surface with few scattered microvilli as seen with the secondary electron imaging mode ; …

Conventional And High Resolution Scanning Electron Microscopy Of Biological Sectioned Material, C. Scala, G. Cenacchi, P. Preda, M. Vici, R. P. Apkarian, Gianandrea Pasquinelli

Scanning Microscopy

Intracellular structures of embedded biological tissues (rat kidney, myocardium and small intestine) were observed by conventional-scanning electron microscopy (C-SEM) and high-resolution scanning electron microscopy (HR-SEM) after glass knife sectioning. C-SEM of semi -thin sections of material processed the same way as conventional transmission electron microscopy (TEM) provided strong backscattered electron (BSE)-dependent, two-dimensional secondary electron images (SEI(-)) which precisely integrated and further extended previous light microscopy (LM) observation of the same specimen. In addition, the three-dimensional (3-D) arrangement of intracellular organelles was appreciated using a mixture of acetone-soluble acrylic resin in place of epoxy resin embedding. Since the identification of such …

Phenotypic Subpopulations Of Macrophages And Dendritic Cells In Human Spleen, Patrick J. Buckley

Scanning Microscopy

Using immunohistochemical techniques and a large number of monoclonal antibodies, the presence and distribution of phenotypic subpopulations of macrophages (Mθs) and dendritic cells in human spleen were assessed. The results of this study show that different subsets of Mθs and dendritic cells are present in the spleen and that some of these occupy discrete microanatomic locations . In the red pulp (RP) certain antigens are expressed by different proportions of uniformly distributed Mθs in the cords . On the other hand, some antigens are present on Mθs that form clusters of variable size within the red pulp . These include …

Innervation And Vascular Pharmacodynamics Of The Mouse Spleen, Frank D. Reilly

Scanning Microscopy

Neurohistochemical and in vivo and electron microscopic methods demonstrated α-and ,β-adrenergic receptors and adrenergic innervation in arterioles and "arterial" capillaries of the mouse spleen. Such innervation and receptors in venules and channels within the red pulp were sparse. Cholinergic innervation and receptors were judged to be absent in the microvasculature. Histamine elicited arteriolar dilation which was blocked by metiamide suggesting the presence of H₂ receptors. However , following blockade of H₂ receptors, histamine produced arteriolar constriction. Serotonin elicited only venular constriction. Lactic acid caused arteriolar constriction; bradykinin and prostaglandins (PG) E₂ and PGF_2α triggered arteriolar constriction, …

An Ecological Description Of Three Black Bass Species In Two Northeastern Kentucky Muskellunge Streams, Albert F. Surmont Jr.

Morehead State Theses and Dissertations

A thesis presented to the faculty of the Department of Biological and Environmental Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Albert F. Surmont, Jr. on December 10, 1990.

Ultrastructural Effects Of Ionizing Radiation On Plant Cells, Á. Keresztes, E. Kovács

Scanning Microscopy

Ultrastructural effects of ionizing irradiation were investigated on the specific constituents of plant cells, primarily in fruits, with reference to mushroom cells and comparable data in the literature. In the cell wall the dissolution of the middle lamellae, probably due to radiation damage of pectin, and irregular thickenings were found. In the vacuole the quantity of inclusions changed, or unusual aggregations appeared, presumably in connection with altered phenolic biosynthesis . In chloroplasts the senescence was inhibited, and dedifferentiation occurred into agranal state. In amyloplasts starch hydrolysis was hind ere d. These platidial effects are considered as visible signs of inhibition …

The Role Of Polar Pili In The Adherence Of Pseudomonas Aeruginosa To Injured Canine Tracheal Cells: A Semiquantitative Morphologic Study, D. E. Zoutman, W. C. Hulbert, B. L. Pasloske, A. M. Joffe, K. Volpel, M. K. Trebilcock, W. Paranchych

Scanning Microscopy

Pseudomonas aeruginosa adheres to respiratory epithelial cells in a highly specific fashion. In order to study the role of P. aeruginosa polar pili in the adherence process we conducted a quantitative morphological electron microscopic examination of P. aeruginosa adherence to SO₂ injured canine tracheal cells in vitro. A pilin lacking background strain of P. aeruginosa PAK (BLP2) was constructed using a gene replacement and it in turn was engineered to express either the pilin gene of P. aeruginosa PAO, PAK , or no pilin gene . After 30 minutes incubation of these bacterial strains with injured canine tracheal …

Diapause In The Earthworm, Aporrectodea Longa: Morphological And Quantitative X-Ray Microanalysis Of Cryosectioned Chloragogenous Tissue, A. J. Morgan, C. Winters

Scanning Microscopy

The earthworm, Aporrectodea longa, which experiences an apparent obligatory physiological resting state (“diapause”) in the temperate Summer, was collected monthly from February through to October. Morphological examination of the chloragocytes, and quantitative electron probe X-ray microanalysis of their constituent chloragosome granules prepared by cryoultramicrotomy and air-dried/smearing, were undertaken over this period. Worms entered diapause in May, and emerged from it between August and September. The long-term energy stores in the form of lipid, in addition to the more usual polysaccharide (glycogen) reserves, were accumulated by early diapause; the lipid was gradually consumed during diapause. In addition, the structure and composition …

Scanning Electron Microscopic Study Of Pulp Stones In Human Permanent Teeth, O. Le May, J. C. Kaqueler

Scanning Microscopy

Scanning electron microscopy was used to examine pulp stones which are small calcified formations found in the coronal and/or radicular part of the dental pulp. Pulp stones range considerably in size and shape. Most are round or oval but others can be irregular and may correspond to a reduced duplicate of the pulp chamber anatany. Both free and attached pulp stones were observed. The surface aspect was variable and frequently exhibited large resorption zones. Three characteristic features were observed on fractures a) no characteristic organization where the mineralized mass is compact and hanogeneous, b) a concentric architecture around an initiating …