Biology Commons^™

Epigenetic Regulation Of Nuclear Hormone Receptor Dax-1, Michael B. Heskett

Master's Theses

DAX-1 (NR0B1) is an orphan nuclear receptor that plays a key role in the development and maintenance of steroidogenic tissue in mammals. Dax-1 is also expressed in mouse embryonic stem (ES) cells and is required to maintain pluripotency. Duplication of the X-chromosome in the region containing the NR0B1 gene results in sex reversal, and mutations in NR0B1 cause adrenal hypoplasia congenita. DAX-1 has been observed to act as a corepressor of other nuclear receptors including androgen receptor (AR), estrogen receptor (ER), and steroidogenic factor 1 (SF-1). In addition to pluripotent ES cells, DAX-1 is primarily expressed in select tissues of …

Examining The Role Of Dax-1 In Regulation Of Cell Proliferation In Human Breast Cells, Amy E. Scandurra

Master's Theses

DAX-1 is a member of the Nuclear Hormone Receptor superfamily and acts as a transcriptional repressor. DAX-1 plays an important role in the development of adrenal and gonadal tissues. In addition to its role in normal cell development and differentiation, DAX-1 appears to have some influence on the progression of cancer. This work aims to examine the role of DAX-1 in regulation of proliferation in breast cancer. In our study, we have expressed DAX-1 in a DAX-1 deficient breast cancer cell line as well as knocked down DAX-1 expression in normal DAX-1 positive breast cells. Through these experiments, we were …

The Conservation Genetics Of Two Emydid Turtles: Emydoidea Blandingii And Malaclemys Terrapin, Charlotte Lizana Petre

Master's Theses

Conservation of turtles is complicated by their sensitivity to habitat degradation and overexploitation. I used microsatellites and standard population genetic analyses to explore genetic diversity, population structure, paternity and demographic history in two emydid turtles that are currently experiencing threats to their survival. The Blanding’s turtle, Emydoidea blandingii, has experienced habitat fragmentation throughout its range, and this study focuses on a population in Massachusetts where hatchlings from one population are being translocated to establish a new population. I found evidence of multiple paternity within clutches and found no significant reduction in genetic diversity when comparing the source population and …

Age, Growth, And Simulation Modeling To Characterize Fish Populations At Two Reservoirs In South-Central Kansas, Brian Serpan

Master's Theses

Several fish populations in Kansas are heavily exploited. To obtain insight into the response of fish populations to management actions, fisheries biologists must obtain as much information as possible with limited resources. To address these challenges, biologists often use age and growth information to understand the age structure of the populations, estimate recruitment and mortality, and gain insight into environmental and genetic factors influencing growth. In addition, age and growth data are used to generate yield-per-recruit models, which allow biologists to extrapolate population trends and make broad predictions about population responses to different management actions. Cheney and El Dorado reservoirs …

Effect Of Grain, Region, And Human Influence On Higher Taxonomic Surrogacy, Frances Owen

Master's Theses

Surrogacy is a common tool within conservation and can be useful when scientists lack detailed knowledge of a system. Higher taxonomic surrogacy is appealing because it can save time and money. However, this technique might vary in effectiveness depending on the taxonomic level, spatial grain, region, and impact by humans. In this thesis I addressed some of the common concerns with higher taxonomic surrogacy using Breeding Bird Atlas data from six states (Colorado, Florida, Michigan, New York, Pennsylvania, and Washington). I compared the coefficients (slopes) of my models rather than the R2 values relied on by other higher taxonomic surrogacy …

The Ontogeny Of Whistle Production In Infant Atlantic Bottlenose Dolphins (Tursiops Truncatus) During The First Thirty Days Of Life, Brittany Leigh Jones

Master's Theses

The manner in which dolphin calves acquire their whistle repertoire is largely unknown. This paper focuses on whistle development in four bottlenose dolphin calves during the first thirty days of life in order to increase our understanding of the early emergence of whistles and whistle-like vocalizations. The acoustic parameters of whistle-type vocalizations (i.e., whistles and whistlesquawks) that coincided with a bubblestream emission from the focal calf and/or its mother were analyzed, as were the behavioral states of the mother-calf pair during the emission of such vocals. Mother and calf whistle rates are inversely related, with the mother whistling more often …

Identification And Characterization Of Msab Gene Involved In Biofilm Formation And Virulence In Staphylococcus Aureus, Amelsaad Elbarasi

Master's Theses

Staphylococcus aureus is an important human pathogen that causes a wide variety of life-threatening infections ranging from minor skin and oral infections to severe infections, such as bacteremia, pneumonia, osteomyelitis, or endocarditis due to the presence and secretion of a large number of virulence factors that are controlled by global virulence regulators in complex networks. Furthermore, S. aureus infections have become a threat to public health because of their high potential to form biofilm, and their ability to resist a wide range of antibiotics has exacerbated further. Therefore, understanding the regulatory networks and developing a drug targeting these networks has …

Characterizing Populations Of Non-Coding Rnas In Karenia Brevis At Different Times Of The Diel Cycle, Scott Boyd Anglin

Master's Theses

Karenia brevis is a mixotrophic, marine dinoflagellate found in the Gulf of Mexico that generates periodic, if not annual, harmful algal blooms (also known as “red tides”) in certain coastal areas. In an effort to better understand the biology of this organism, a functional genomics project has been initiated. As part of that project, it has been determined that a significant number of natural antisense transcripts (NATs) as well as double-stranded RNA (dsRNA) molecules exist within the transcriptome of K. brevis. I hypothesize that the non-coding NATs, similar to microRNAs (miRNAs) in other organisms play a role in regulating …

Role Of Msaa Gene In Regulation Of The Msaabcr Operon And Biofilm Development In Staphylococcus Aureus, Ahmed Alzuway

Master's Theses

Staphylococcus aureus is an important human pathogen that causes wide variety of diseases ranging from chronic biofilm associated infection to acute life threatening infection such as bacteremia, pneumonia, osteomyelitis, or endocarditis, despite the progress with antibiotics used in the treatment of bacterial infections. Furthermore, increased use of prosthetic and indwelling devices in modern medical practices has led to increased infections due to S. aureus. Treating S. aureus infections have become difficult owing to its ability to resist most of the antibiotics; this problem is further exacerbated by ability of MRSA strains to form biofilms. Emergence of community-acquired methicillin resistance …

Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher

Master's Theses

• Climate change models predict an increase in frequency and amplitude of extreme weather events, including heat waves. To better predict how the composition and distribution of plant assemblages might respond to these changes in temperature, it is important to understand how species currently respond to these extremes. Photosynthetic thermal tolerance (T₂₅)and photosynthetic recovery (RT₂₅) were quantified in 27 species. We also studied the relationships between T₂₅, RT₂₅ and leaf mass per area (LMA). Leaf temperature was also monitored in the field.
• Leaves used in this study were collected from two distinct …

Investigation Of Chromosome Size Effect On The Rate Of Crossovers In The Meiotic Yeast Saccharomyces Cerevisiae, Lanie Maria Galland

Master's Theses

Meiosis is a specialized type of cell division characterized by a single round of DNA replication and two rounds of chromosome segregation, ultimately resulting in four haploid cells. During meiosis I, chromosomes align and reciprocal recombination results in the formation of a crossover, creating the tension required to properly segregate homologs during the first round of meiosis.

Two mechanisms involved in regulating the occurrence of crossing over are assurance and interference. Crossover assurance describes the phenomenon that at least one crossover will form between each pair of homologous chromosomes during prophase I. Crossover interference, on the other hand, describes the …

Optimization Of Growth Parameters For Algal Regrowth Potential Experiments, Chadwick D. Boggess

Master's Theses

Water cost is one of the key deterrents in making algal biofuels a feasible alternative to traditional petroleum fuels. Research into recycling of algal media was conducted in a laboratory setting at the California Polytechnic State University in San Luis Obispo. A growth assay was created to allow for algal cultures, specifically Ward’s Chlorella sp., to proliferate in sealed culture vessels. Bold’s Basal Medium (BBM) was selected as the media due to its extensive use with freshwater algal strains. However, this medium can limit algal growth through nutrient limitation and it became necessary to augment the original recipe. 50mM …

The Role Of Sirtuin Inhibitors On The Proteomic Responses Of The Mussels Mytilus Galloprovincialis And Mytilus Trossulus To Menadione Induced Oxidative Stress, Hayley C. Chilton

Master's Theses

Global climate change imposes physiological constraints on marine ecosystems that can alter the distribution of intertidal organisms. In one such instance, the native cold-adapted mussel Mytilus trossulus is being replaced along its southern range by the invasive warm-adapted Mytilus galloprovincialis. These blue mussels occur throughout rocky intertidal zones where they are subjected to greatly varying environmental conditions known to induce oxidative stress. We hypothesize that while under acute stress, related Mytilus congeners undergo a shift in redox potential from NADH-fueled respiratory pathways to pathways producing NADPH as a way to decrease the production of reactive oxygen species (ROS) and …

Timing And Intensity Of Steer Use On Old World Bluestem (Bothriochloa Ischaemum) And Blue Grama (Bouteloua Gracilis) In Southern Mixed-Grass Prairie, Jessica Casey

Master's Theses

Yellow bluestem (Bothriochloa ischaemum), an invasive species, was introduced as a forage species and as a roadside grass for erosion control. Yellow bluestem can negatively interact with native grasslands and reduce biodiversity. Livestock tend to avoid yellow bluestem after accumulation of standing lignified tissue, particularly at the end of the growing season. Mowing has been used in pasture situations to remove excess grass for hay and over coarse grass left from the previous season. It is essential to understand the role livestock play as either a catalyst for control or preventing further invasion of yellow bluestem. Quantification of the timing …

The Human Dimensions Of Waterfowl Hunters At Cheyenne Bottoms Wildlife Area, Barton County, Kansas, Jason K. Black

Master's Theses

An on-site human dimension survey was applied at Cheyenne Bottoms Wildlife Area (CHBW), Kansas, to evaluate waterfowl hunters’ support for three alternative management strategies. The strategies included in the survey were: 1) the creation of a refuge-in-time where hunting would be allowed for the entire day, but only on odd-numbered calendar dates, 2) the designation of an existing pool as a primitive pool, i.e., no motorized watercraft allowed, and 3) the creation of a refuge-in-time where hunting would only be allowed in a given pool from ½ hour before sunrise to 1300 hours, but hunting would be allowed every day …

Nest Survival Of Grassland Breeding Birds In A Southern Mixed-Grass Prairie Wetland, Clinton Helms

Master's Theses

As a group, grassland birds have been declining significantly since European settlement of the prairie. The subsequent plowing of the prairie by settlers was compounded by fire suppression, resulting in a patchwork of cultivated fields with intermittent tracts of overgrown grassland. Over an interval of ~200 years, these practices lead to an estimated decline of 96 % of native tallgrass prairie habitat. Due to the imperiled status of grassland birds, an emphasis has been placed on managing for this particular group throughout the southern mixed-grass prairie region. I investigated the effects of adaptive three-pasture rotational grazing treatments (3ROT) versus traditional …

Antimicrobial Resistance Of Channel Catfish Intestinal Microflora In The Arkansas And Ninnescah Rivers In Kansas, Jordan R. Hofmeier

Master's Theses

Antimicrobial compounds have been used by humans to counteract bacterial infections since 1910. Overuse of these compounds in clinical and agricultural applications has led to rapid evolution and global spread of antimicrobial resistance and rivers are the main receiving body for antimicrobials and resistant bacteria from urban effluents and agricultural runoff. When antimicrobial-resistant bacteria enter the aquatic environment, water acts as a physical pathway for their distribution. Subsequently, resistance genes become established in natural systems and pose threats to human health and ecological processes. Due to these potential threats, antimicrobial resistance in the aquatic environment should be closely monitored. To …

Possible Effects Of Black-Tailed Prairie Dogs (Cynomys Ludovicianus) On Abundance And Diversity Of Raptors And Small Mammals In Mixed And Shortgrass Prairie Of Western Kansas, Nina M. Luna

Master's Theses

The black-tailed prairie dog (Cynomys ludovicianus) is a burrowing rodent native to the Great Plains currently experiencing large population declines. It is debated whether prairie dogs are keystone species; however, areas with prairie dogs have higher levels of biodiversity and presumably increased biotic interactions. The goal of this study is to quantify the importance of black-tailed prairie dogs, hereafter prairie dog, by comparing abundance and diversity of raptors and small mammals on prairie dog (PD) and non-prairie dog (NON) inhabited prairie. A significant difference was detected between the two treatments (PD and NON) in the number of raptors counts; the …

Dispersal Of Antibiotic-Resistant Bacteria Near Central Great Plains Feedlots, Jennifer R. Pfannenstiel-Klaus

Master's Theses

Antibiotic resistance is a growing concern in medical and veterinary settings. Resistance can be worsened by misuse and overuse of antibiotics. Such situations can give rise to highly resistant organisms. Ciprofloxacin, a synthetic, broad-spectrum antibiotic used to treat gram-positive and gram-negative infections in humans, has similar chemical structure to enrofloxacin, which is used to treat animals. Cross-resistance might arise because of that similarity. This research describes the dispersal and prevalence of bacteria that exhibit ciprofloxacin resistance in relation to feedlots in the central Great Plains region. Six times in 2013, six feedlots were sampled for airborne bacterial communities at, upwind …

Habitat Associations Of Grassland Birds Along A Gradient Of Eastern Red Cedar Succession In Central Kansas, Scott W. Schmidt

Master's Theses

Grassland birds have declined more rapidly than any other avian taxa in North America. While woody encroachment is often cited as a threat, some grassland-dependent species requiring habitat with scattered trees or shrubs also are declining at statistically significant rates. To better understand the ecological costs and benefits of woody vegetation from a brush management perspective, I studied bird-habitat associations along a canopy cover gradient of eastern red cedar (Juniperus virginiana). Habitat associations were tested by the comparing the relative abundance of breeding birds between 3 habitat treatment levels (0% eastern red cedar canopy cover [open grassland], < 5% eastern red cedar canopy cover [light encroachment], and > 5-25% eastern red …

Inferring Herpetofaunal Distributions And Habitat Preferences For Conservation Planning, Lisa M. Prowant

Master's Theses

Global climate change is a serious threat to global biodiversity (IPCC, 2001). Due to their limited dispersal ability, reptiles and amphibians might be more vulnerable to rapid climate change than are other taxonomic groups (Gibbons et al., 2000). Herpetofauna in south-central Kansas was sampled from May through August in 2012 and 2013. Seven study sites spanning Meade, Clark, Comanche, and Barber counties were sampled. Drift fence and cover-board traps were arranged in transects at each site to capture reptiles and amphibians. Species were also sampled through surveys on all-terrain vehicles and on foot. Two thousand nine hundred and forty five …

Description Of An Unusual Cervical Vertebral Column Of A Plesiosaur From The Kiowa Shale, Ian N. Cost

Master's Theses

The Early Cretaceous (Albian) Kiowa Shale of Clark County, Kansas consists mainly of dark gray shale with occasional limestone deposits that represent a near shore environment. Faunal lists have been published based on fragmentary materials; however, few individual specimens have been described in the last 100 years. Here an unusual plesiosaur specimen (KUVP 16375) is described. The specimen consists of 17 cervical vertebrae: 10 articulated and 7 disarticulated. Some of the vertebrae are uniquely preserved with an atypical ventral excavation not present in known plesiosaur vertebrae. It is not clear whether or not this character is of phylogenetic or diagnostic …

Comparison Of Small Mammal Communities In Ephemeral Wetlands And Wet Meadows During Drought, Brian M. Zinke

Master's Theses

Ephemeral wetlands are characterized by a cyclical hydropattern, ranging from complete inundation to a total absence of surface water. This cycle between wet and dry phases is necessary for the flora of ephemeral wetlands to perpetuate. However, little research has been done to study the response of the non-avian fauna to these cycles, particularly during the dry phase. I live trapped small mammals by using Sherman live traps and conducted vegetation surveys monthly (May–August in 2012 and May–July in 2013) in the ephemeral wetlands and the surrounding wet meadows of the Cheyenne Bottoms basin in central Kansas. Drought occurred both …

Life History Of A Dune-Dwelling Rhaphidophorid, Utabaenetes Tinkham, In The San Rafael Desert Of Utah, Ryan M. Shofner

Master's Theses

The camel cricket, Utabaenetes(tanneri Tinkham, has been little studied. This study gathered information on the basic life history and behavior of this species, which is found only in the San Rafael Desert and adjacent Colorado Plateau in areas of loose sand or active dunes. The daily activity pattern is matutinal, and individuals construct burrows for shelter in the afternoon. The diet of U.(tanneri is omnivorous, composed of plant material, detritus, and conspecific crickets. Utabaenetes(tanneri has been found in the diet of several predatory species, although the total number of observed predation instances is low. Utabaenetes(tanneri might be a Batesian mimic …

Three-Dimensional Reconstruction Of Marine Clay Nano- And Microstructure By Transmission Electron Microscopy: Analysis Of Fabric And Pore Network, Jessica Rae Gardner Douglas

Master's Theses

Three-dimensional reconstructions of marine fine-grained sediment open a new dimension for studying nano- and microscale organo-clay fabric important to improving and advancing organic matter (OM) sequestration and fluid flow dynamics modeling. I created 3-D reconstructions of clay fabric and pore pathways from serial sections and photographic mosaics obtained using transmission electron microscopy. These reconstructions show aggregations of clay domains, surrounding OM, and pore networks. I examined a Model sample (laboratory consolidated) with 1% OM and a Natural sample (polychaete fecal pellet) with high levels of OM. Three-dimensional reconstructions were segmented into 300 nm cube subsamples to make highly localized qualitative …

Taxonomy, Diversity, And Distribution Patterns Of Portunid Crab Megalopae In The Northern Gulf Of Mexico During Fall Of 2003, Carley Rain Knight

Master's Theses

The field of zooplankton biology contributes to more accurate stock assessments as well as to a greater understanding of the marine food web. However, adequate information for the invertebrate component of zooplankton is lacking compared to the ichthyoplankton component. In this thesis, identification of Portunidae (Crustacea: Decapoda) megalopae collected during the fall of 2003 from a NOAA SEAMAP cruise revealed 7 species and 11 morphs with 90% of the total density comprised of Callinectes sapidus, Achelous gibbesii, Callinectes similis, Achelous spinicarpus, and Achelous sp.I. Keys and detailed descriptions are provided along with photographs and morphological drawings for each morph to …

Distance Sampling As A Technique To Monitor Pronghorn In Kansas, Jared H. Oyster

Master's Theses

Accurate and precise estimates of abundance are crucial for wildlife management. Wildlife agencies spend large amounts of time and money to obtain estimated abundance. The Kansas Department of Wildlife Parks and Tourism (KDWPT) has conducted strip transect (ST) counts biannually since 1963 to estimate pronghorn (Antilocapra americana) abundance in Kansas. However, the accuracy and reliability of results are questionable. Distance sampling (DS) is a method used to estimate abundance of a biological population. All perpendicular distances of objects to the transect line are recorded; however, there is no designated strip width and no assumption that all objects are detected. I …

Elucidating The Transcriptional Regulation Of Col2a1a In Zebrafish, Sonja Dabizljevic

Master's Theses

Cartilage is an important tissue in vertebrates beginning in the early embryo where it lays down the scaffolding for the skeleton, and continuing through adulthood where it makes up joints and intervertebral disks. The major component of cartilage is a filamentous protein known as Collagen type II, alpha 1 (Col2a1). Mutations in col2a1 in humans can lead to multiple congenital disorders and the early onset of joint and retinal deterioration. Our laboratory is interested in understanding the conserved transcriptional regulation of this critical structural gene utilizing the zebrafish, Danio rerio. Previously, we identified a 310 bp regulatory region (R2) 1.7 …

Functional Characterization Of A Novel Thioredoxin Domain-Containing Protein Of The Malaria Parasite Plasmodium, Rachel Kooistra

Master's Theses

A novel thioredoxin domain-containing protein of the malaria parasite Plasmodium was identified and found to be conserved among eukaryotes. This protein belongs to the phosducin-like family of proteins (PhLPs), and was therefore assigned the name PhLP1, since it is the first phosducin-like protein to be identified in Plasmodium. PhLPs have been found to have various roles in G-protein signaling, cell cycle progression, and protein folding. However, the biochemical mechanism by which PhLPs perform their function is unknown. Here is described the cloning and biochemical characterization of both PhLP1 and its human homolog TXNDC9. Both purified PhLP1 and TXNDC9 showed enzymatic …

Environmental Drivers Of Leaf Breakdown Rate In An Urban Watershed, Ashley Rachelle Cook

Master's Theses

Leaf litter breakdown is a critical ecosystem process in urban streams, but environmental conditions in urban streams may generate confounding effects on breakdown rates. Reduced abundance of macroinvertebrate shredders may slow breakdown, but rates may increase if high nutrient concentrations stimulate microbial decomposers and if flooding enhances leaf fragmentation. We used the litter bag technique to measure the relative importance of multiple environmental drivers on breakdown of eastern cottonwood (Populus deltoides) leaves at 5 sites throughout the North Branch of the Chicago River watershed. Sites spanned a gradient of urbanization, but no specialized macroinvertebrate shredders were present at any sites. …