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Distribution Of Ground-Layer Plant Species In A Fragmented Landscape In The Corozal District, Belize, Central America, Divan Catzim

Browse all Theses and Dissertations

In this study, I specifically looked at three major issues regarding 36 target plant species in a fragmented landscape in the Corozal district, Belize: 1) Determine woodlot characteristics that tend to favor the target species. 2) Determine plant characteristics that tend to favor the target species. 3) Determine whether age and size of a woodlot favors the presence of the target species. The study area was divided into three areas and each area had woodlots varying in sizes and ages. 36 plant species were sampled in all woodlots upon which woodlot characteristics and species characteristics were associated with the number …

Investigation Of Interactions Between Rev And Microtubules: Purification Of Wild-Type And Mutant Rev Protein And Optimization Of Microtubule Depolymerization Assays, Miller, Kelly Robbins

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As a logical pharmaceutical target for antiviral drugs, HIV-1 Rev is a regulatory protein essential for viral infection (Hope, 1999). The development of antiviral drugs that target Rev has been hindered by the lack of high-resolution structural information due to the protein's tendency to aggregate in solution. While searching for solution conditions rendering Rev amenable to crystallographic analyses, Watts et al., (2000) discovered a novel in vitro interaction between Rev and microtubules (MTs) whereby addition of equimolar Rev and tubulin forms bilayered rings called Rev-tubulin toroidal complexes (RTTs). RTTs are similar to those seen when MTs are mixed with certain …

Analysis Of Sex Reversal And Tra-2 Nucleotide Variation In Tropical And Temperate Clades Of Caenorhabditis Briggsae, Irene Zelepuhin

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Reproductive isolation results when members of the same species cannot reproduce due to either prezygotic or postzygotic mechanisms, therefore restricting gene flow between populations. A leading model describing reproductive isolation developed by J.B. Haldane (1922) states, "When offspring from two different animal species have one sex that is rare, absent, or sterile, that sex is the heterozygous (XO) or heterogametic (XY) sex". Haldane's rule is illustrated among various animal taxa regardless of which sex is heterogametic. To date, Caenorhabditis mating tests are the only example of Haldane's rule that is caused by sexual transformation and not gender specific lethality or …

Immunological And Developmental Effects Of Polybrominated Diphenyl Ethers (Pbdes) And 2,3,7,8-Tetrachloro-P-Dioxin (Tcdd) In Birds, Randy T. Stetzer

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This thesis contains two separate and distinct research projects with a common overall theme - the study of immunotoxicity associated with the developmental exposure of young birds to halogenated chemicals posing environmental concern. These chemicals share many chemical characteristics, including environmental ubiquity and longevity, one has been studied extensively since the 1970s, and one is a relatively new environmental contaminant with few studies pertaining to toxicological affects on humans or wildlife. Specific summaries of each study begin each project chapter. The first study was entitled Developmental and Immunological Effects of a Commercial Mixture of PBDE Flame Retardants in Chicken Embryos. …

Modulation Of The 3'Igh Regulatory Region (3'Igh Rr), A Prospective In Vitro Screening Tool For Identifying Potential Immunotoxicants, Rebecca Anne Henseler

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The immune system is critical to human survival. However, assessing alterations of immune function by potential immunotoxicants is complicated by the diffuse nature of the immune system, which is composed of various effector cells each with differing effector functions. Current immunotoxicity testing is limited to animal studies. We have developed a model, which may provide an in vitro alternative to animal studies in identifying immunotoxicants that specifically target B cell function (i.e., alteration of immunoglobulin (Ig) or expression and antibody secretion). This model consists of a well-characterized B cell line, CH12.LX, which appears to appropriately model primary B cell function. …

The Arabidopsis Homologs Of Trithorax (Atx1) And Enhancer Of Zeste (Clf) Establish ‘Bivalent Chromatin Marks’ At The Silent Agamous Locus, Abdelaty Saleh, Ayed Al-Abdallat, Ivan Ndamukong, Raul Alvarez-Venegas, Zoya Avramova

School of Biological Sciences: Faculty Publications

Tightly balanced antagonism between the Polycomb group (PcG) and the Trithorax group (TrxG) complexes maintain Hox expression patterns in Drosophila and murine model systems. Factors belonging to the PcG/TrxG complexes control various processes in plants as well but whether they participate in mechanisms that antagonize, balance or maintain each other’s effects at a particular gene locus is unknown. CURLY LEAF (CLF), an Arabidopsis homolog of enhancer of zeste (EZ) and the ARABIDOPSIS HOMOLOG OF TRITHORAX (ATX1) control the expression of the flower homeotic gene AGAMOUS (AG). Disrupted ATX1 or CLF function results in misexpression of AG, recognizable …

Flagellar Motility And Structure In The Hyperthermoacidophilic Archaeon Sulfolobus Solfataricus, Zalán Szabó, Musa Sani, Maarten Groeneveld, Benham Zolghadr, James Schelert, Sonja-Verena Albers, Paul H. Blum, Egbert J. Boekema, Arnold J.M. Driessen

School of Biological Sciences: Faculty Publications

Flagellation in archaea is widespread and is involved in swimming motility. Here, we demonstrate that the

structural flagellin gene from the crenarchaeaon Sulfolobus solfataricus is highly expressed in stationary-phasegrown

cells and under unfavorable nutritional conditions. A mutant in a flagellar auxiliary gene, flaJ, was

found to be nonmotile. Electron microscopic imaging of the flagellum indicates that the filaments are composed

of right-handed helices.

Evaluation Of Metals In A Defined Medium For Pichia Pastoris Expressing Recombinant Β-Galactosidase, Bradley A. Plantz, Kenneth W. Nickerson, Stephen D. Kachman, Vicki L. Schlegel

School of Biological Sciences: Faculty Publications

Culture growth and recombinant protein yield of the Pichia pastoris GS115 methanol utilization positive system were studied in response to the types and levels of metals present in the growth medium and the supplemental salts typically used for these fermentations. Magnesium and zinc were both required to support cell growth but at significantly reduced levels compared to the control. However, supplementation with calcium, cobalt, iron, manganese, iodine, boron, and molybdenum were not required to sustain cell mass. When the medium was reformulated with only zinc and magnesium, the cells grew to 12–15 generations, which are expected for high cell density …

Asymmetric Localizations Of Lin-17/Fz And Mig-5/Dsh Are Involved In The Asymmetric B Cell Division In C. Elegans, Mingfu Wu, Michael A. Herman

School of Biological Sciences: Faculty Publications

LIN-44/Wnt and LIN-17/Frizzled (Fz) function in a planar cell polarity (PCP)-like pathway to regulate the asymmetric B cell division in Caenorhabditis elegans. We observed asymmetric localization of LIN-17/Frizzled (Fz) and MIG-5/Disheveled (Dsh) during the B cell division. LIN-17∷GFP was asymmetrically localized within the B cell prior to and after the B cell division and correlated with B cell polarity. Asymmetric localization of LIN-17∷GFP was dependent upon LIN-44/Wnt and MIG-5/Dsh function. The LIN-17 transmembrane domain and a portion of the cysteine-rich domain (CRD) were required for LIN-17 function and asymmetric distribution to the B cell daughters, while the conserved KTXXXW …

Plant Mitochondrial Recombination Surveillance Requires Unusual Reca And Muts Homologs, Vikas Shedge, Maria P. Arrieta-Montiel, Alan C. Christensen, Sally Ann Mackenzie

School of Biological Sciences: Faculty Publications

For >20 years, the enigmatic behavior of plant mitochondrial genomes has been well described but not well understood. Chimeric genes appear, and occasionally are differentially replicated or expressed, with significant effects on plant phenotype, most notably on male fertility, yet the mechanisms of DNA replication, chimera formation, and recombination have remained elusive. Using mutations in two important genes of mitochondrial DNA metabolism, we have observed reproducible asymmetric recombination events occurring at specific locations in the mitochondrial genome. Based on these experiments and existing models of double-strand break repair, we propose a model for plant mitochondrial DNA replication, chimeric gene formation, …

Parasites, Proteomics And Performance: Effects Of Gregarine Gut Parasites On Dragonfly Flight Muscle Composition And Function, Rudolf J. Schilder, James H. Marden

School of Biological Sciences: Faculty Publications

In previous work, we found that dragonflies infected with gregarine gut parasites have reduced muscle power output, loss of lipid oxidation in their flight muscles, and a suite of symptoms similar to mammalian metabolic syndrome. Here, we test the hypothesis that changes in muscle protein composition underlie the observed changes in contractile performance. We found that gregarine infection was associated with a 10-fold average reduction in abundance of a ~155·kDa fragment of muscle myosin heavy chain (MHC; ~206·kDa intact size). Insect MHC gene sequences contain evolutionarily conserved amino acid motifs predicted for calpain cleavage, and we found that calpain digestion …

Microarray Challenges In Ecology, Jan E. Kammenga, Michael A. Herman, N. Joop Ouborg, Loretta Johnson, Rainer Bretling

School of Biological Sciences: Faculty Publications

Microarrays are used to measure simultaneously the amount of mRNAs transcribed from many genes. They were originally designed for gene expression profiling in relatively simple biological systems, such as cell lines and model systems under constant laboratory conditions. This poses a challenge to ecologists who increasingly want to use microarrays to unravel the genetic mechanisms underlying complex interactions among organisms and between organisms and their environment. Here, we discuss typical experimental and statistical problems that arise when analyzing genome-wide expression profiles in an ecological context. We show that experimental design and environmental confounders greatly influence the identification of candidate genes …

An Epidemiological Model Of Rift Valley Fever, Holly D. Gaff, David M. Hartley, Nicole P. Leahy

Biological Sciences Faculty Publications

We present and explore a novel mathematical model of the epidemiology of Rift Valley Fever (RVF). RVF is an Old World, mosquito-borne disease affecting both livestock and humans. The model is an ordinary differential equation model for two populations of mosquito species, those that can transmit vertically and those that cannot, and for one livestock population. We analyze the model to find the stability of the disease-free equlibrium and test which model parameters affect this stability most significantly. This model is the basis for future research into the predication of future outbreaks in the Old World and the assessment of …

Detection Of Mitochondrial Insertions In The Nucleus (Numts) Of Pleistocene And Modern Muskoxen, Sergios-Orestis Kolokotronis, Ross De Macphee, Alex D. Greenwood

Biological Sciences Faculty Publications

Background: Nuclear insertions of mitochondrial sequences (NuMts) have been identified in a wide variety of organisms. Trafficking of genetic material from the mitochondria to the nucleus has occurred frequently during mammalian evolution and can lead to the production of a large pool of sequences with varying degrees of homology to organellar mitochondrial DNA (mtDNA) sequences. This presents both opportunities and challenges for forensics, population genetics, evolutionary genetics, conservation biology and the study of DNA from ancient samples. Here we present a case in which difficulties in ascertaining the organellar mtDNA sequence from modern samples hindered their comparison to ancient DNA …

Factors That Affect Distribution Of Two Species Of Killifish In Northeast Florida Marshes, Stacy N. Galleher

UNF Graduate Theses and Dissertations

Fundulus heteroclitus and the closely related F. grondis are mainly distributed along the Atlantic coast of the U.S from Maine to Northeast Florida and from the East coast of Florida throughout the Gulf of Mexico, respectively. Both are resident salt marsh fishes whose range is thought to overlap in Northeast Florida, making them an ideal study system to examine resource partitioning between two closely related species. The objective of this study was to examine the effects of temperature and elevation on potential habitat partitioning of these two species. It is hypothesized that the northern species, F. heteroclitus, would have a …

Cell Signaling Pathways In Lps-Mediated Apoptosis Of Dedifferentiated Hepatoma Cells, Michael Ryan Reidy

Masters Theses

Using liver tumor cells and their dedifferentiated cell lines, mechanisms underlying tissue specific gene expression can be studied. We have derived cell lines, from liver tumor cells, which fail to express liver genes. These cells are termed "dedifferentiated cells". One significant observation made was that cells which fail to express liver genes also rapidly undergo programmed cell death (known as apoptosis) under the influence of the bacterial endotoxin lipopolysaccharide (LPS). Understanding the mechanism of how liver function relates to cell apoptosis is the goal of this study.

Apoptosis is known to play a critical role in development and homeostasis, yet …

Comparison Of Avian Nest Success Among Linear Wooded Habitats In An Agricultural Landscape, Terri J.E. Thompson

Masters Theses

In the Midwest, urban expansion and more intensive agricultural practices have reduced habitat available to most species of breeding birds. Linear wooded habitats including fencerows and riparian strips are a common habitat feature in many agricultural landscapes. Changes in agricultural practices and the subsequent reduction in grasslands and fencerows have lead to greater breeding densities in species that use the remaining fencerows as nest sites. This may lead to a lower nesting success due to factors such as higher predation risk. Specifically, it is not known how such linear habitats currently contribute to avian populations in central Illinois.

We monitored …

Effects Of Food Deprivation, Body Size, And Egg Load On The Mating Behavior Of Female Japanese Beetles, Popillia Japonica Newman (Coleoptera: Scarabaeidae), Natasha Tigreros

Masters Theses

Female condition may play an important role in the mating frequency of species that mate at foraging areas. For example, in species where feeding females are more easily encountered or less resistant to mating than females that are performing other activities, low energy levels could increase mating activity. We studied the relationship between female condition and mating activity in the Japanese beetle, Popillia japonica (Coleoptera: Scarabaeidae) in a laboratory study. We altered condition by depriving some females of food for one day and comparing their mating behavior to well-fed females. Our results showed that the effect of condition on mating …

Red Squirrel Distribution And Habitat Use In Illinois, Corinna Hanson

Masters Theses

The North American red squirrel (Tamiasciurus hudsonicus) is a species of special concern in Illinois due to its restricted geographic range and low numbers. This species occupies a broad geographic range in North America and is usually associated with the boreal forests of Canada and coniferous forests in the Rocky Mountain range. The squirrels also occupy deciduous and mixed deciduous-coniferous forests in the eastern U.S. In Illinois, available habitat is suboptimal, and limited to pine plantations and small tracts of deciduous forest embedded in an agricultural matrix landscapе. Information on the spatial distribution of red squirrels in northeastern Illinois was …

Mating, Kinship, And Population Structure In Illinois Beaver Populations, Joanne C. Crawford

Masters Theses

The North American beaver, Castor canadensis, is an important wildlife species for a variety of reasons. As a furbearer, it provides income and recreation to trappers throughout the state. As a wetland engineer, it helps maintain functioning ecosystems (Naiman et al. 1986, McKinstry and Anderson 2002). Finally, the beaver serves as a model organism for studies of mating and kinship, as it has beed reported to be almost exclusively monogamous (Sun 2003).

Monogamy in mammals is generally restricted to the primates, canids, and rodents, and is defined as a mating system in which a pair remains together for at least …

Classification Of Illinois Lakes And Reservoirs And Evaluation Of The Potential Use Of Phytoplankton As Biocriteria, Jessica A. Rasmussen

Masters Theses

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Glow Sticks As Effective Bait For Capturing Aquatic Amphibians In Funnel Traps, Kristine L. Grayson, Andrew W. Roe

Biology Faculty Publications

Funnel traps of various designs have been used to capture adults and larvae of aquatic amphibians (e.g., Buech and Egeland 2002; Richter 1995). Most studies use unbaited funnel traps to capture amphibians while others have used shrimp or salmon eggs (Adams et al. 1997). Light traps and light sticks are commonly used in studies of fish, particularly larvae (Doherty 1987; Marchetti et al. 2004), but have not been widely used to capture amphibians. Glow sticks have been mentioned briefly in the literature as a means to increase capture rates of aquatic amphibians (Smith and Rettig 1996), but no studies have …

Habitat Use And Overwintering Ecology Of The Northern Watersnake (Nerodia Sipedon) On An Artificial Levee In Central Illinois, Melanie J. Olds

Masters Theses

Several reptile species have populations that are in decline, and anthropogenic habitat loss and alteration are arguably the factors having the greatest impact on these species. More attention has been paid to understanding the activity season habitat needs in snakes than on the habitat requirements for overwintering. I examined the patterns of both activity season and overwintering habitat use by a population of northern watersnakes (Nerodia sipedon) that inhabit an artificial levee in central Illinois. My research objectives were to determine how a population of northern watersnakes uses an artificial levee during the activity season and to determine what type …

Influence Of Fish Presence And Removal On Woodland Pond Breeding Amphibians, J. Brian Towey

Masters Theses

Predatory fish can have devastating effects on populations of amphibians, many of which are already declining around the world. Land managers seeking to restore disturbed woodland ponds to more historically-accurate conditions may consider removing fish, a potentially difficult or costly process. I report on the effects of introduced sunfish (Lepomis spp.) and black bullhead catfish (Ameiurus melas), and their removal, on the reproductive efforts of three species of amphibians: smallmouth salamanders (Ambystoma texanum), American toads (Bufo americanus) and wood frogs (Rana sylvatica). Using drift fences and pitfall traps around four woodland ponds, amphibians were monitored for one year prior to …

Establishment And Maintenance Of An Asm Student Chapter, Amy Cheng Vollmer

Biology Faculty Works

No abstract provided.

Stabel Isotope Turnover Rates And Diet-Tissue Discrimination In The Skin Of West Indian Manatees: Implcations For Evaluating Their Feeding Ecology And Habitat Use, Christy Alves

Electronic Theses and Dissertations

The West Indian manatee (Trichechus manatus) is an herbivorous marine mammal that occupies freshwater, estuarine, and marine habitats. Despite being considered endangered, relatively little is known about the feeding ecology of either of the two recognized subspecies, the Florida manatee (T.m. latirostris) and Caribbean or Antillean manatee (T.m. manatus). A better understanding of their respective feeding preferences and habitat use is essential to establish criteria on which conservation plans can be based. The present study expands on previous work on manatee feeding ecology by both assessing the application of stable isotope analysis to manatee tissue and providing critical baseline parameters …

Restoration Of Intertidal Oyster Reefs Affected By Intense Recreational Boating Activity In Mosquito Lagoon, Florida, Andrea Barber

Electronic Theses and Dissertations

In recent years, intertidal reefs of Crassostrea virginica (eastern oyster) along central Florida's east coast have suffered extensive losses due to wakes from recreational boats. These wakes have caused extensive shell movement and sediment resuspension which results in large piles of disarticulated shells along the seaward edges of reefs. Dead margins extend up to one meter above mean high water. The creation and enforcement of "no wake" zones in the area are unlikely. Thus, there is an urgent need for an alternative restoration strategy before these oyster reefs decline any further. The goal of this project was to develop a …

Effects Of Isolation On Metapopulation Dynamics In Small-World Networks, Alaina Brooke Bernard

Electronic Theses and Dissertations

Simulation models are valuable for making predictions that may be tested in natural systems and for understanding observed patterns. The simulation model developed for this thesis evaluates the effects of spatial network architecture, including organism dispersal patterns and isolation of habitats, on metapopulations. Two fields were merged throughout this project: metapopulation biology and small-world network theory. Small-world networks are characterized in their extremes as scale-free or single-scale. These models potentially simulate the networks of habitats and corridors in which metapopulations operate. Small-world network theory has been used to describe systems as diverse as rivers, the world-wide-web, and protein interactions, but …

Genetic And Phenotypic Evolution In The Ornate Chorus Frog (Pseudacris Ornata): Testing The Relative Roles Of Natural Selection,, Jacob Degner

Electronic Theses and Dissertations

Understanding how migration, genetic drift, and natural selection interact to maintain the genetic and phenotypic variation we observe in natural populations is a central goal of population genetics. Amphibians provide excellent model organisms for investigating the interplay between these evolutionary forces because amphibians are generally characterized by limited dispersal abilities, high philopatry, and are obligately associated with the areas around suitable habitats (e.g. breeding ponds). Thus, on relatively small geographic scales, the relative effects of all of these evolutionary forces can be studied together. Here, we study the interaction of migration, genetic drift, natural selection, and historical process in the …

Life History And Reproductive Biology Of Clitoria Fragrans Relative To Fire History On The Avon Park Air Force Range, Michelle Nicole Lewis

Electronic Theses and Dissertations

The southeastern coastal plain of the United States is a center of endemism for plants in temperate North America and second only to California among the states. In the southeast, Florida has the largest number of these endemic plants. The largest number of these Florida endemics can be found in the fire maintained scrub and sandhill communities located on sandy ridges in Central Florida. One such endemic is Clitoria fragrans, a rare perennial herb. C. fragrans reproduces via a mixed mating system. It produces both open, chasmogamous flowers and closed, selfed, cleistogamous flowers. Little else is known about its biology. …