Biology Commons^™

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 …

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 …

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 …

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 …

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 …

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. …

The Behavioral And Physiological Effects Of Long-Distance Translocation On Western Rattlesnakes (Crotalus Oreganus), Kory Hayden Heiken

Master's Theses

Long-distance translocation (LDT), the relocation of an animal outside of its home range, is a popular strategy for mitigating conflict between humans and venomous snakes. While LDT has been demonstrated to prevent a snake’s return to the location of capture, it may result in increased mortality, magnitude and frequency of movements, and activity range sizes. Thus, it has generally been discouraged. However, the effects of LDT on stress physiology and thermoregulation have gone largely unstudied in reptiles. To elucidate these effects, we conducted an experimental LDT on Western Rattlesnakes (Crotalus oreganus) on Vandenberg Air Force base in California. …

Lipid Production By Microalgae Treating Municipal Wastewater, James Edward Kelley

Master's Theses

Microalgae hold much promise as a feedstock in liquid biofuel production. Lipid content of microalgae cells range from 30-80% dry weight of biomass. It is projected that microalgae can produce between 1,000-6,500 gallons/acre/year of oil. Currently, production of industrial algae operates in open raceway ponds that use minimal capital and energy inputs to culture algae. Raceway ponds can also be used to grow microalgae from municipal waste streams. Although high biomass productivity can be achieved in these systems, there remains a large production gap between large volumes of biomass cultivation and high lipid content from microalgae cells. Low lipid content …

Protective Effects Of Sphingomyelin Against Uv Photodamage In Human Keratinocytes, Kathleen De Guzman

Master's Theses

Ultraviolet (UV) radiation has been demonstrated in numerous studies to be a major risk factor for non-melanoma skin cancer development. Despite the emergence of current UV-preventative strategies, such as sunscreens and skin-protective clothing, the incidence of non-melanoma skin cancer has continued to rise. This has encouraged investigations on alternative methods for UV prevention. In particular, bovine milk sphingomyelin has been studied for its potential in protecting human skin against UV photodamage. While the previous studies have suggested that sphingomyelin exhibits UV-protective properties in a human skin equivalent model, the exact mechanisms behind sphingomyelin’s photoprotective effects are yet unknown.

This thesis …

The Influence Of Hydrogeomorphology, Soil Redox Conditions, And Salinity On The Spatial Zoning Of Saltgrass, Salt Rush, And Cattails In Scotts Creek Marsh, Swanton Pacific Ranch, Ca, Mark D. Gormley

Master's Theses

Scotts Creek Marsh (SCM) is a small coastal wetland ecosystem in Davenport, CA. The vegetation of SCM is dominated by three halophytic zones comprised of saltgrass, salt rush, cattails. The objectives of the study were (i) to investigate the variables that influence the zoning of the three dominant halophyte communities in SCM and (ii) to the test the effectiveness of Indicator of Reduction in Soil (IRIS) tubes to indicate the reduction of S. The study examined the following parameters from April 6 to July 21, 2013: (i) the HGM of Scotts Creek Marsh, (ii) soil oxidation and reduction (redox) conditions, …

Determining Parentage And The Effects Of Relatedness On Play Partner Preference In Belding's Ground Squirrels, Jessica Weidenbach

Master's Theses

I investigated 1) multiple paternity in Belding’s ground squirrels (Urocitellus beldingi) and 2) social partner preferences in juvenile U. beldingi. Prior work with blood allozymes demonstrated multiple paternity in U. beldingi litters. I evaluated paternity using microsatellite DNA analysis, which is more accurate than examining blood allozymes. My results indicate that multiple paternity in U. beldingi is more extensive than previously shown, occurring in about 90% of litters with more than one juvenile, and averaging 2.95 fathers in multiply sired litters. I also evaluated the hypothesis that play and other social behavior promotes bonding among juvenile female …

An Insight Into The Microbial Diversity And Expression Of Cysteine Protease Inhibitors (Cystatin) In Rickettsia Parkeri Infected Amblyomma Maculatum, Khemraj Budachetri

Master's Theses

Amblyomma maculatum (Gulf Coast tick) is an emerging tick species of public health significance in United States. It is a competent vector of Rickettsia parkeri, an etiological agent of a human rickettsiosis. In this study, we investigated the spotted fever group of rickettsial diversity in A. maculatum based on rickettsial ompA gene PCR. Our results showed A. maculatum harbors R. parkeri, R. amblyommii, and R. endosymbiont of A. maculatum. While only R. parkeri was detected in female salivary glands which suggest its ability to traffic from midgut to salivary glands via hemocoel. The presence of R. parkeri was further …

Comparative Analysis Of Antiviral Responses In Mouse Embryonic Stem Cells And In Mesenchymal Stem Cells, Jundi Wang

Master's Theses

Embryonic stem cells (ESCs) are cells that have unlimited capacity for selfrenewal and differentiation. These properties make ESCs a great cell source for application in regenerative medicine. When used for cell therapy, ESC-derived cells could be placed in a wounded area that is likely to be exposed to various pathogens. However, it is not well-understood whether ESCs and ESC-derived cells have active antiviral responses against infectious agents from the environment. To answer this important question, I comparatively analyzed the antiviral responses of ESCs and mesenchymal stem cells (MSCs, C3H10Tl/2 cell line) to infectious agents. Using the expression of type I …

Testing Subspecies Limits In Monardella Villosa, Taylor Mclaughlin Crow

Master's Theses

Several subspecies of Monardella villosa (California Coyote Mint) have been distinguished on the basis of leaf thickness, shape, and trichome characteristics, yet many intermediates are known. We investigated morphological differences in natural populations of two subspecies (M. v. subsp. villosa and M. v. subsp. franciscana) in the Scott Creek watershed, north of Davenport, in Santa Cruz County, CA. Monardella villosa subsp. franciscana grows in coastal scrub in gulches and ocean terraces whereas subsp. villosa grows at more protected inland sites. Morphological difference between subspecies may be adaptations to these different habitats. I grew plants in a common garden at Cal …

Associations Between Alcohol Consumption And Fasting Blood Glucose In Young Adults, Julie Ann Lucca

Master's Theses

Current research shows moderate alcohol consumption is associated with decreased risk of diabetes and excessive consumption or binge drinking can cause insulin resistance and diabetes. In 2010, diabetes was the seventh leading cause of death in the United Statesand was responsible for significant health complications: blindness, kidney failure, and limb amputations, and is a large national economic burden. Fasting blood glucose (FBG) is a tool used to help diagnose diabetes. Abnormally high FBG, ≥100 mg/dl, is indicative of diabetes and pre-diabetes. Few studies have observed diabetic prevalence among young adults or college students. Studying young adults can help provide added …

Root Kinematics In Relation To Temperature And Genome Size In Wild And Domesticated Zea., Avery B. Cromwell

Master's Theses

We studied root kinematics in relation to temperature and genome size variation in teosinte (Zea mays subspecies parviglumis) and corn (Zea mays subspecies mays). Corn had significantly faster radicle growth than teosinte when grown at a constant temperature. Both species exhibited variation in seed size and for each species larger seeds had faster root growth. Genome size was not significantly correlated with faster radicle growth rates across multiple land races of corn. To examine temperature dependent growth in corn and teosinte, a germinated seedling was grown at multiple temperatures. Growth rates at these temperatures were used …

Interactions Between Protozoan Prey (Phylum Protista) And Their Mosquito Predators (Order Diptera, Family Cuclicidae) Prey Size And Predator Behavior Effects, Jeffrey Jay Skiff

Master's Theses

Mosquitoes (Diptera. Culicidae) are insects that are medically important as adults as they vector numerous diseases. Yet, understanding the ecology of the larval stage can lead to surveillance and control of adult populations. Aedes albopictus, Aedes triseriatus, Cu/ex corona/or, and Culex quinquefasciatus are four species of mosquito that co-occur in discarded automobile tires. Mosqui-to larvae feed on microorganisms (including protozoans) and particulate organic matter Most larval feeding experiments. howt:ver, have dealt exclusively with bacteria, fungi , and particulate organic matter Although bactena and fungi are important sources of nitrogen and lipids, they may be 111sufficient sources of carbon, which may …

Home Range And Habitat Use Of Santa Rosa Island Foxes (Urocyon Littoralis Santarosae), Elizabeth Marie Drake

Master's Theses

Island foxes (Urocyon littoralis) are currently listed as federally endangered on four of the six Channel Islands to which they are endemic. The Santa Rosa Island (SRI) population declined by 99% during the 1990’s due to non-native golden eagle (Aguila chrysaetos) predation and is currently the lowest fox population (~280) and density (0.86 foxes/km²) of any of the Channel Islands. The goals of this study were to assess new miniaturized GPS technology and to quantify home range and habitat use of the SRI population. This is only the second use of Global Positioning System (GPS) …

Behavior And Ecosystem Effects Of The Invasive Asian Clam (Corbicula Fluminea) In Urban Streams, Kayla Turek

Master's Theses

Invasive species can be detrimental to freshwater ecosystems. By completing laboratory and field studies to observe processes and behaviors of the invasive Asian Clam (Corbicula fluminea), I documented pathways whereby this invasive species impacts aquatic ecosystems under conditions typical of urbanized streams I found. The predominant pathways by which clams impacted nitrogen (N) cycling was through excretion thus increasing ammonium (NH4+) flux out of sediment and through bioturbation, which increased nitrate (NO3-) diffusion to the sediment and dinitrogen gas (N2) production (i.e., denitrification). The effect was greater under urban conditions, where C. fluminea population density and water column NO3- were …

Fungal Biofilm Colonization And Succession On Artificial Reefs In The North-Central Gulf Of Mexico, Amy Leigh Salamone

Master's Theses

This study represents the first characterization of natural mixed-species fungal biofilm communities on artificial reefs in the marine environment. Previous fungal biofilm studies have failed to observe the naturally-occurring biodiversity in coastal areas, which comprise the most utilized zone of the marine environment. Artificial reefs can increase fishing yields, amplify oyster habitats, contribute to shoreline stabilization, promote good water quality, and deter pollution. Proper management practices of artificial reefs require knowledge of the colonization of these new habitats by marine organisms and their subsequent succession. Fungi, along with bacteria, archaea, protists, algae, and diatoms, quickly form a complex biofilm on …

Effects Of Hurricane Disturbance On The Stopover Ecology Of Intercontinental Landbird Migrants In Coastal Louisiana, Emily Johanna Lain

Master's Theses

Few studies have considered the impact of weather events on migratory birds during stopover, and essentially none on how hurricanes affect their stopover biology during spring passage. About two thirds of eastern North American forest breeding bird species migrate twice annually between temperate breeding areas and subtropical and tropical wintering grounds, and movement in relation to the Gulf of Mexico (GOM) is a conspicuous and important part of that migration system. During inclement weather or winds inconsistent with travel direction, migratory birds oft.en/a/lout and concentrate by the thousands in forest patches that occur along the northern coast of the GOM. …

Immunostimulatory And Cellular Toxic Effects Of Single-Stranded Rna On Cancer Cells, Chengwen Teng

Master's Theses

Whether 5'-triphosphate-single-stranded-RNA (5 '-ppp-ssRNA) is immunostimulatory was controversial in the literature. In order to clarify the immunostimulatory effect of 5'-ppp-ssRNA, we synthesized ssRNAs and tested the IFNp (interferon-beta) level and cellular toxicity of ssRNAs in SKOV3 cells. In this work, we confirmed that 5'-ppp-ssRNA (~ 60nt) was immunostimulatory and toxic in SKOV3 cells. 5'-ppp-ssRNA (~ 60nt) led to IFN-P induction and apoptosis in SKOV3 cells. Longer 5' ppp- ssRNA tended to have a higher immunostimulatory effect and cellular toxicity than shorter 5'-ppp-ssRNA. 5'-ppp-ssRNA was more immunostimulatory and toxic than 5'- 0H-ssRNA. If the incubation time of ssRNAs increased, the toxicity …

Seasonal Food Habits Of Burrowing Owls (Athene Cunicularia) In Human-Altered Landscapes, Carie Marie Wingert

Master's Theses

In 2004, I initiated a year-long study to investigate the food habits of burrowing owls (Athene cunicularia). Burrowing owls have been found in a variety of human-altered landscapes; however, little is known about burrowing owl food habits in urban landscapes. Burrowing owl food habits during the non-breeding season are also largely undocumented, despite increasing concern over the survival of overwintering burrowing owls. Differences in prey consumption between reproductive and non-reproductive owls during the breeding season have not yet been examined. I collected pellets over a 12 month period at four study sites affected by different levels of human …

Comparing The Demographics Of Two Steelhead Populations And Their Habitat Characteristics, Eileen Ann Baglivio

Master's Theses

Currently, little is known about the demographics of the Oncorhynchus mykiss irideus, or steelhead trout, populations in San Luis Obispo County. Specifically, demographic information including length, age, and condition when first leaving a watershed for the open ocean is lacking. This thesis takes a closer look at a biological and environmental data collected by the California Department of Fish and Game Central Coast Steelhead and Coho Salmon project under the direction of Associate Biologist Jennifer Nelson. The main goal of this thesis is to analyze demographic and habitat data from the steelhead populations of two northern San Luis Obispo …

Temporal Dynamics Of Galapagos Marine Iguna (Amblyhynchus Cristatus) Haulout, Brianna Gale Payne

Master's Theses

Galápagos marine iguanas (Amblyrhynchus cristatus) briefly forage in marine habitats but spend their remaining time hauled out on land. A wide range of diurnal activities, from social and thermoregulatory behaviors to sleep and food processing, occurs during haulout. To understand the dynamics of haulout and foraging in relation to environmental factors, I fit compartmental models derived from ordinary differential equations to field data collected daily from 30 April to 16 May 2011 at two sites—one Sandy and one Rocky—at Cabo Douglas, Isla Fernandina. The best model for haulout at the Sandy site accounts for 77–80% of observed variability and includes …

Organization And Composition Of The Α21-Ii Region Of Human Chromosome 21, William Ziccardi

Master's Theses

The purpose of this project was to develop a better map of the alpha 21-II region of human chromosome 21 in regards to size and primary sequence of the five alphoid clusters that comprise the region and to explore the evolutionary relationships that exist within and between these clusters. Several HC21 BACs were identified as containing strong sequence identities to alpha 21-II clones and were mapped to various alpha 21-II clusters. It was revealed that both monomeric and HOR alphoid clusters can be found in the alpha 21-II region. Phylogenetic analysis revealed separate evolutionary histories for the monomeric and HOR …

Influence Of Detritus Levels And Organic Pollution On Interspecific Resource Competition, Oviposition Behavior, And Larval Survival Of Two Tire-Inhabiting Mosquito Species (Diptera: Culicidae), David Wayne Allgood

Master's Theses

Mosquitoes (Diptera: Culicidae) are vectors of disease in the adult stage, but understanding the factors affecting distributions of the immature stages is important to the understanding and control of adult populations. Discarded automobile tires comprise important larval mosquito habitats. The Asian tiger mosquito (Aedes albopictus) and the southern house mosquito (Culex quinquefasciatus) are two medically important species commonly found in tires, but factors affecting their larval distributions in tires have not been studied, nor have their interspecific interactions. I investigated the effects of chemicals associated with organic pollution on oviposition preferences and larval survival of both …

Tick Infestations And Their Consequences For Migratory Songbirds During Spring Stopover, Johnny Michael Sellers Jr.

Master's Theses

Migratory birds face a number of challenges during their seasonal movement from tropical/sub-tropical Central and South America to more temperate North America. Maintaining health during migration is of particular concern. This study seeks to understand how haematophageous ectoparasites, such as ticks (Ixodida), impact host body condition as they feed on passerines during migration. We hypothesized that foraging location would impact tick acquisition by migrants and that tick burdens during migration would negatively impact body condition. We surveyed 2,064 birds during spring 2009 and 2010 and found that 2.4% of the surveyed birds were infested with one or more …

Thermal Tolerance Of Age-0 Gulf Of Mexico Striped Bass (Morone Saxatilis): Ontogenetic And Genetic Effects, Corey Robert Anderson

Master's Theses

Striped bass, Morone saxatilis, were historically abundant in the Gulf of Mexico region but were largely extirpated from most Gulf rivers by the early 1960s. Since 1967 hatchery stocking has supported populations in Mississippi rivers and to date there is no evidence of natural reproduction. Intolerance of striped bass to high water temperature is a potential factor negatively impacting Gulf striped bass survival and reproductive fitness, and may be a limiting factor to reintroduction of the species in Mississippi. This work contributed to restoration efforts by establishing molecular tools necessary for genetic monitoring of striped bass restoration, and evaluating …

Investigating The Roles Of Ndj1 And Tid1 In Crossover Assurance In Saccharomyces Cerevisiae, Rianna Knowles

Master's Theses

Meiosis is the specialized process of cell division utilized during gametogenesis in all sexually reproducing eukaryotes, which consists of one round of DNA replication followed by two rounds of chromosome segregation and results in four haploid cells. Crossovers between homologous chromosomes promote proper alignment and segregation of chromosomes during meiosis.

Crossover interference is a genetic phenomenon in which crossovers are non-randomly placed along chromosomes. Crossover assurance ensures that every homologous chromosome pair obtains at least one crossover during Prophase I. Crossovers physically connect homologous pairs, allowing spindle fibers to attach and separate homologs properly. However, some organisms have shown an …