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Characterization Of Membrane Potentials In Vascular Smooth Muscle Of Hagfish, Lamprey And Trout, Prentiss Jones Jr.

Dissertations

The objective of this study was to characterize membrane potentials in systemic arteries of Pacific hagfish, Eptatretus stouti, Rainbow trout, Onchorhyncus mykiss, and Sea lamprey Petromyzon marinus. Previous studies have characterized membrane potentials in piscine tissue. However, these studies utilized non-vascular tissues such as cardiac muscle and skeletal muscle (69, 161). Characterization of membrane potentials in fish vasculature is without precedent in the literature. The hypothesis of this study was that membrane potentials in fish vascular smooth muscle differ little between species when comparable vasculature is evaluated.

Genetic Considerations For The Conservation And Management Of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) In Yellowstone National Park, David J. Janetski

Theses and Dissertations

A key component to conservation is an accurate understanding of genetic subdivision within a species. Despite their ecological and economic importance, relatively little is understood about the genetic structuring of Yellowstone cutthroat trout in Yellowstone National Park. Here, we use traditional (Fst, Rst, Nm, and AMOVA) and modern (Bayesian assignment tests, coalescent theory, and nested clade analysis) analytical approaches to describe the population genetic subdivision of cutthroat trout spawning populations in Yellowstone Lake and to identify genetically distinct population segments throughout Yellowstone National Park. Evidence for restricted gene flow between spawning populations within Yellowstone Lake was detected using nested clade …

Occurrence Of Metacercariae Of Diplostomum And Tylodelphys Species (Diplostomidae) In Clarias Species (Clariidae) Fishes From Lake Victoria, M. J. Musiba, G. Nkwengulila

Tanzania Journal of Science

The localisation and abundance of the metacercariae of Diplostomum and Tylodelphys species among the clariids of Lake Victoria were investigated between April and December 2001. Four species viz. Clarias gariepinus (271), C. alluaudi (65), C. werneri (50) and C. liocephalus (47) were examined, but only C. gariepinus was infected in the brain case and along the nasal cavity. Prevalence of metacercariae was high (>70%). Prevalence and mean intensity were similar between male and female fish. Mean intensity increased with fish size and declined in larger fish for D. mashonense; but declined with the increase in fish size for Tylodelphys …

Diversity And Abundance Of Small Mammals In The Serengeti Kopjes, Tanzania, C. D. Timbuka, J. D. Kabigumila

Tanzania Journal of Science

Diversity and abundance of small mammals in the Serengeti kopjes were studied between November 2000 and February 2002. From 22,500 trap-nights and 3,300 bucket-nights, 4,903 small mammals in 18 species, 14 genera, 6 families and 3 orders were recorded. Muridae was the most dominant family with nine species. The highest number of species was recorded in the Maasai (14), Mbuzi Mawe (13) and Seronera (12) kopjes. The least number of species recorded in the Simba, Barafu and Wogakuria kopjes, with eight species each. Species diversity was highest in the Maasai kopjes (H'=2.337) and lowest in the Wogakuria kopjes (H'=1.794), with …

Progeny Of Germ Line Knockouts Of Asi2, A Gene Encoding A Putative Signal Transduction Receptor In Tetrahymena Thermophila, Fail To Make The Transition From Sexual Reproduction To Vegetative Growth, Shuqiang Li, Lihui Yin, Eric S. Cole, Rupa A. Udani, Kathleen M. Karrer

Biological Sciences Faculty Research and Publications

The ciliated protozoan Tetrahymena has two nuclei: a germ line micronucleus and a somatic macronucleus. The transcriptionally active macronucleus has about 50 copies of each chromosome. At sexual reproduction (conjugation), the parental macronucleus is degraded and new macronucleus develops from a mitotic product of the zygotic micronucleus. Development of the macronucleus involves massive genome remodeling, including deletion of about 6000 specific internal eliminated sequences (IES) and multiple rounds of DNA replication. A gene encoding a putative signal transduction receptor, ASI2, (anlagen stage induced 2) is up-regulated during development of the new macronuclei (anlagen). Macronuclear ASI2 is nonessential for vegetative …

Phylogeographic Analyses Of Obligate And Facultative Cave Crayfish Species On The Cumberland Plateau Of The Southern Appalachians, Jennifer Elizabeth Buhay

Theses and Dissertations

Cave systems and their unique biota are widely viewed as highly endangered, yet very little is known about basic life history, ecology, distributions, habitat requirements, and evolutionary relationships of subterranean species. The crux of the problem in cave studies is the assumption that traditionally defined morpho-species represent distinct evolutionary lineages. Convergence is exhibited in the morphologies of many animal groups, vertebrate and invertebrate, which leads to confusion in diagnosing species' boundaries, geographic distributions, gene flow routes, and imperilment. This dissertation research includes phylogeographic analyses of freshwater cave-dwelling crayfishes in the Southern Appalachians, a global hotspot of subterranean biodiversity. By examining …

Development Of An In Vitro Protocol To Study The Effect Of Estrogen On Osteoblast Activity, Sourik Ganguly

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science & Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Sourik Ganguly on July 7, 2006.

Identification Of Anopheles (Nyssorhynchus) Marajoara (Diptera: Culicidae) In Bolivia Using Polymerase Chain Reaction And A Restriction Endonuclease, Gary Fritz, C. L. Brelsfoard, R. Rodriguez

Faculty Research & Creative Activity

Anopheles (Nyssorhynchus) marajoara Galvão & Damasceno (Diptera: Culicidae) is a member of the Albitarsis cryptic species complex and is a primary vector of human Plasmodium in parts of Brazil. We report the first record of An. marajoara in the department of Cochabamba and confirm its presence in the department of Santa Cruz, Bolivia. We also describe a PCR protocol producing a single amplicon (≈340 bp) of a section of the internal transcribed spacer 2 specific for members of the Albitarsis species complex; the polymerase chain reaction protocol did not amplify the DNA of 17 other species in the subgenus Nyssorhynchus. …

Ecological Fitting As A Determinant Of The Community Structure Of Platyhelminth Parasites Of Anurans, Daniel R. Brooks, Virginia León-Règagnon, Deborah Mclennan, Derek Zelmer

Faculty Publications

Host–parasite associations are assumed to be ecologically specialized, tightly coevolved systems driven by mutual modification in which host switching is a rare phenomenon. Ecological fitting, however, increases the probability of host switching, creating incongruences between host and parasite phylogenies, when (1) specialization on a particular host resource is a shared characteristic of distantly related parasites, and (2) the resource being tracked by the parasite is widespread among many host species. We investigated the effect of ecological fitting on structuring the platyhelminth communities of anurans from a temperate forest and grassland in the United States and tropical dry and wet forests …

Evidence For Absence Of Latch-Bridge Formation In Muscular Saphenous Arteries, Shaojie Han, John E. Speich, Thomas J. Eddinger, Krystina M. Berg, Amy S. Miner, Chris Call, Paul H. Ratz

Biological Sciences Faculty Research and Publications

Large-diameter elastic arteries can produce strong contractions indefinitely at a high-energy economy by the formation of latch bridges. Whether ownstream blood vessels also use latch bridges remains unknown. The zero-pressure medial thickness and lumen diameter of rabbit saphenous artery (SA), a muscular branch of the elastic femoral artery (FA), were, respectively, approximately twofold and half-fold that of the FA. In isolated FA and SA rings, KCl rapidly (s) caused strong increases in isometric stress (1.2 x 10⁵ N/m²) and intracellular Ca²⁺ concentration ([Ca²⁺]_i; 250 nM). By 10 min, [Ca²⁺]i declined …

Stress Responses In Tropical Sparrows: Comparing Tropical And Temperate Zonotrichia, Haruka Wada, Ignacio T. Moore, Creagh W. Breuner, John C. Wingfield

Biological Sciences Faculty Publications

Seasonal modulation of the adrenocortical response appears to be ubiquitous in mid- to high- latitude vertebrates but has not been investigated in tropical vertebrates. Previous studies demonstrate that temperate passerines show seasonality in corticosterone secretion and corticosteroid binding globulin capacities. We examined seasonal and sex differences in the stress response in an equatorial population of Zonotrichia capensis, the only Zonotrichia that breeds in the tropics, and compared the results with those of northern Zonotrichia. Seasonal differences in tropical Zonotrichia would presumably be independent of photoperiod and thus directly related to such activities as reproduction and feather molt. In addition, we …

Linking Scales In Stream Ecology, Winsor H. Lowe, Gene E. Likens, Mary E. Power

Biological Sciences Faculty Publications

The hierarchical structure of natural systems can be useful in designing ecological studies that are informative at multiple spatial scales. Although stream systems have long been recognized as having a hierarchical spatial structure, there is a need for more empirical research that exploits this structure to generate an understanding of population biology, community ecology, and species-ecosystem linkages across spatial scales. We review studies that link pattern and process across multiple scales of stream-habitat organization, highlighting the insight derived from this multiscale approach and the role that mechanistic hypotheses play in its successful application. We also describe afrontier in stream research …

Facilitation By Pinus Flexilis During Succession: A Hierarchy Of Mechanisms Benefits Other Plant Species, Dayna Baumeister, Ragan M. Callaway

Biological Sciences Faculty Publications

Studies of facilitation have primarily been limited to single mechanisms, species, or environments. We examined interacting mechanisms governing the facilitative effects of Pinus flexilis on two later successional understory species, Pseudotsuga menziesii and Ribes cereum, in different microhabitats and seasons at the ecotone between the Rocky Mountain forests and Great Plains grasslands in Montana, USA. In field surveys, 69% of Pseudotsuga and 91% of Ribes were located beneath P. flexilis even though P. flexilis subcrowns accounted for a small proportion of available habitat. For three years, we monitored the survival of Pseudotsuga and Ribes seedlings experimentally planted beneath …

Estimating Detection Probablities Of River Birds Using Double Surveys, Robert J. Fletcher Jr., Richard L. Hutto

Biological Sciences Faculty Publications

We describe a method for surveying birds in river habitats that allows for rapid assessment across broad spatial scales and estimation of detection probabilities. Our river survey approach incorporates a double-survey technique, whereby observers in two canoes simultaneously survey birds along a river reach. Data are in the form of a two-sample mark-recapture history, and covariates suspected of influencing detection probabilities can be included in the modeling process and evaluated using information-theoretic approaches. We provide an example using the method along the Madison and upper Missouri rivers in Montana. Overall, detection probabilities for each observer ranged from 57% to 89%, …

Exposure Of Nervous System Cells To Polychlorinated Biphenyls (Pcbs), Results In Alterations Of Neurotrophic Factor Expression, Gordon H. Gurley

Dissertations

Toxic insult by PCBs results in learning and memory deficits in humans. Alterations in expression of neurotrophic factors (NF) and/or their receptors have been linked to changes in learning and memory. How PCBs affect cognition is not known. We suggest that PCBs affect cognition by altering NF expression.

We exposed cultured C6 rat glioblastoma cells (an astrocyte cell-line) to medium containing PCB (Aroclor 1254 (10ppm)). Control cells were treated with dimethyl sulfoxide (DMSO) or regular medium. Enzyme-linked immunosorbent assays (ELISA) were used to determine glial cell-line derived neurotrophic factor(GDNF) and nerve growth factor (NGF) concentrations in all samples. We also …

Molecular Analysis Of The Effects Of Atrazine On Xenopus Laevis Frogs, Ronald Edward Celestine

Dissertations

Atrazine, the most commonly used herbicide in the U.S., has been implicated as one of the factors that may be causing the worldwide decline of amphibians. First, I examined effects of atrazine on laboratory raised Xenopus laevis tadpoles, treated from 5 days post fertilization to NF stage 65/66 with a concentrationof 25 ppb of atrazine. This study showed no significant difference in body weight, length and metamorphic rate.

Second, I used DNA microarrays to examine mRNA expression levels of genes in atrazine treated and control Xenopus laevis tadpoles. I found significant changes in gene expression levels of 18 genes. These …

Transport Of Galectin-3 Between The Nucleus And Cytoplasm. I. Conditions And Signals For Nuclear Import, Peter J. Davidson, Su Yin Li, Andrew G. Lohse, Rianna Vandergaast

University Faculty Publications and Creative Works

Galectin-3, a factor involved in the splicing of pre-mRNA, shuttles between the nucleus and the cytoplasm. We have engineered a vector that expresses the fusion protein containing the following: (a) green fluorescent protein as a reporter of localization, (b) bacterial maltose-binding protein to increase the size of the reporter polypeptide, and (c) galectin-3, whose sequence we wished to dissect in search of amino acid residues vital for nuclear localization. In mouse 3T3 fibroblasts transfected with this expression construct, the full-length galectin-3 (residues 1-263) fusion protein was localized predominantly in the nucleus. Mutants of this construct, containing truncations of the galectin-3 …

The Effect Of Male Competition On Female Choice In Brandt’S Vole, Lasiopodomys Brandti, Jianjun Zhang, Dazhao Shi, Lixing Sun

All Faculty Scholarship for the College of the Sciences

The effect of male competition on female choice in the Brandt’s vole (Lasiopodomys brandti) was studied in the laboratory. Using a two-way choice test, we showed that when males did not compete, estrous females preferred and mated with the dominant males, but non-estrous females preferred subordinate males. However, when males competed, all dominant males gained the priority to mate, and the amicable behaviour between males, regardless of their dominant status, and between non-estrous females increased, compared with the behaviour between males and the estrous females. These results showed that interactions among Brandt’s voles were not only influenced by …

Vertical Migration Of The Toxic Dinoflagellate Karenia Brevis And The Impact On Ocean Optical Properties, Oscar Schofield, John Kerfoot, Kevin Mahoney, Mark A. Moline, Matthew Oliver, Steven Lohrenz, Gary Kirkpatrick

Biological Sciences

Vertical migration behavior is found in many harmful algal blooms; however, the corresponding impact on ocean optical properties has not been quantified. A near-monospecific population of the dinoflagellate Karenia brevis was encountered off the west coast of Florida. The community was tracked for 24 hours by following a Lagrangian drifter deployed at the beginning of the experiment. A suite of inherent optical and cellular measurements was made. Over the 24 hour period, the K. brevis population increased during the day with concentrations peaking in the late afternoon (1600 local daylight time) in the upper 2 m of the water column. …

Genetic And Maternal Determinants Of Effective Dispersal: The Effect Of Sire Genotype And Size At Birth In Side-Blotched Lizards, Barry Sinervo, Ryan Calsbeek, Tosha Comendant, Christiaan Both

Dartmouth Scholarship

We assessed genetic factors on progeny dispersal due to sire color morph genotypes in a field pedigree and lab crosses, and we measured maternal effects by studying both natural and experimentally induced egg size variation. Progeny were released into nature upon hatching, but we recorded dispersal distance at maturity, which reflects effective dispersal after viability selection has run its course. Progeny dispersal was significantly affected by sire genotype. Progeny from orange sires dispersed the farthest. Progeny from blue sires dispersed intermediate distances. Progeny from yellow sires were the most philopatric. Sire genotype effects interacted with egg size. In particular, enlarged …

Growth, Feeding And Reproduction Of The Catfish Eremophilus Mutisii (Pisces : Trichomycteridae), From Artificial Reservoirs In Colombia, Gabriel Pinilla, Maritza Abril, Esperanza González

Faculty Publications

The catfish, Eremophilus mutisii, was cultured under different densities in artificial rainfall reservoirs at Caldas, Boyaca, Colombia. At capture, the average total length of the animals was 10 cm and the weight ranged between 9 and 10 g. These fish were in initial stages of sexual development. After a year in the reservoirs, they had increased in length and weight as follows (densities in parentheses): 5.22 cm and 27.23 g (0.5 individuals/m(2))); 1.98 cm and 8.79 g (1 individual/m(2)), and 2.45 cm and 0.82 g (2 individuals/m(2)). They were at the early stages of sexual maturity, and their condition …

The Environmental Impact Of Dietary Choice And Agriculture In California, Harold J. Marlow Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

Food demand influences agricultural production. Modern agricultural practices have resulted in polluted soil, air and water, eroded soil, dependence on imported oil, and loss of biodiversity. The goal of this research is to investigate the environmental impact of pesticide and fertilizer application, water consumption, and energy used to produce commodities for a vegetarian and non vegetarian diet in California. The working assumption is that greater number and amount of inputs are associated with greater environmental impact. The literature supports this notion. To accomplish this goal, dietary preferences were quantified using the Adventist Health Study and state agricultural data were collected …

An Experimental Approach To Modeling The Strength Of Canine Teeth, Patricia W. Freeman, Cliff A. Lemen

School of Natural Resources: Faculty Publications

The strength of canine teeth in several carnivores is found through direct fracture experiments. The average forces required to break the canines of adult animals are coyote 1170 N, red fox 533 N, bobcat 737 N and raccoon 512 N. Stresses created in teeth at the breaking load are predicted by finite-element analysis and beam theory. The ultimate tensile stress sustainable in these teeth is 338 MPa in adult animals. The large pulp cavity in the canines of young animals significantly weakens the bases of their teeth (by about 25%), but as the animal ages the pulp cavity decreases and …

Coexistence Of The Niche And Neutral Perspectives In Community Ecology, Mathew A. Leibold, Mark A. Mcpeek

Dartmouth Scholarship

The neutral theory for community structure and biodiversity is dependent on the assumption that species are equivalent to each other in all important ecological respects. We explore what this concept of equivalence means in ecological communities, how such species may arise evolutionarily, and how the possibility of ecological equivalents relates to previous ideas about niche differentiation. We also show that the co-occurrence of ecologically similar or equivalent species is not incompatible with niche theory as has been supposed, because niche relations can sometimes favor coexistence of similar species. We argue that both evolutionary and ecological processes operate to promote the …

A Minimally Invasive Method Of Piscine Tissue Collection And An Analysis Of Long-Term Field-Storage Conditions For Samples, James Campanella, John V. Smalley

Department of Biology Faculty Scholarship and Creative Works

Background: The acquisition of high-quality DNA for use in phylogenetic and molecular population genetic studies is a primary concern for evolutionary and genetic researchers. Many non-destructive DNA sampling methods have been developed and are used with a variety of taxa in applications ranging from genetic stock assessment to molecular forensics. Results: The authors have developed a field sampling method for obtaining high-quality DNA from sunfish (Lepomis) and other freshwater fish that employs a variation on the buccal swab method and results in the collection of DNA suitable for PCR amplification and polymorphism analysis. Additionally, since the circumstances of storage are …

Cadherin2 (N-Cadherin) Plays An Essential Role In Zebrafish Cardiovascular Development, Brian Bagatto, Jessie Francl, Bei Liu, Qin Liu

Biology Faculty Research

Background: Cadherins are cell surface adhesion molecules that play important roles in development of vertebrate tissues and organs. We studied cadherin2 expression in developing zebrafish heart using in situ hybridization and immunocytochemical methods, and we found that cadherin2 was strongly expressed by the myocardium of the embryonic zebrafish. To gain insight into cadherin2 role in the formation and function of the heart, we analyzed cardiac differentiation and performance in a cadherin2 mutant, glass onion (glo).

A Structural Analysis And Assessment Of The Bjorklunden Forest, Andrew Allan Link

Lawrence University Honors Projects

A common assumption in ecology is that stability within an ecosystem is reached through equilibrium. In actuality, the mechanisms that help maintain a healthy ecosystem are based upon heterogeneity and scale multiplicity. This study assessed the vegetation organization at Bjorklunden as a function of time and space. Comparisons were made to previous research that demonstrated both similarities and differences in the vegetational components of the forest. Certain areas of the forest that were previously believed to be in a permanent steady-state were proved otherwise. While other areas that were thought to mature and climax, did not. The forest at Bjorklunden …

An Essential Role For Endocytosis Of Rhodopsin Through Interaction Of Visual Arrestin With The Ap-2 Adaptor, Nicholas R. Orem, Luxi Xia, Patrick J. Dolph

Dartmouth Scholarship

Previously, we have identified a class of retinal degeneration mutants in Drosophila in which the normally transient interaction between arrestin2 (Arr2) and rhodopsin is stabilized and the complexes are rapidly internalized into the cell body by receptor-mediated endocytosis. The accumulation of protein complexes in the cytoplasm eventually results in photoreceptor cell death. We now show that the endocytic adapter protein AP-2 is essential for rhodopsin endocytosis through an Arr2-AP-2beta interaction, and mutations in Arr2 that disrupt its interaction with the beta subunit of AP-2 prevent endocytosis-induced retinal degeneration. We further demonstrate that if the interaction between Arr2 and AP-2 is …

The Effects Of Nitrate Levels On The Response Of Pimephales Promelas To Conspecific Chemical Alarm Cues, Lucas J. Borgstrom

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Evolutionary Epidemiology Of Endemic Gal¿Pagos Birds And Their Parasites, Noah Kerness Whiteman

Dissertations

In order to better understand parasite diversification, I went to the Gal¿pagos Islands to study the ecology and evolution of a model bird-parasite system, which included four phylogenetically independent ectoparasite lineages infecting the Gal¿pagos Hawk (Aves: Buteo galapagoensis). The parasites comprised two lice (Insecta: Phthiraptera: Amblycera, Ischnocera), a lousefly (Diptera: Hippoboscidae) and an avian skin mite (Acari: Epidermoptidae). Ultimately, my goal was to examine ectoparasite evolutionary epidemiology and disease susceptibility in relation to the host¿s ecological and colonization history. At the outset, I hypothesized that parasite natural history was key in influencing the coalescent process. Accordingly, I found differences …