Life Sciences Commons^™

Differential Response Of Barrier Island Dune Grasses To Species Interactions And Burial, April Harris, Julie C. Zinnert, Donald R. Young

Biology Publications

Barrier islands are at the forefront of storms and sea-level rise. High disturbance regimes and sediment mobility make these systems sensitive and dynamic. Island foredunes are protective structures against storm-induced overwash that are integrally tied to dune grasses via biogeomorphic feedbacks. Shifts in dune grass dominance could influence dune morphology and susceptibility to overwash, altering island stability. In a glasshouse study, two dune grasses, Ammophila breviligulata and Uniola paniculata, were planted together and subjected to a 20 cm burial to quantify morphological and physiological responses. Burial had positive effects on both plants as indicated by increased electron transport rate and …

Aggregate Stability And Water Retention Near Saturation Characteristics As Affected By Soil Texture, Aggregate Size And Polyacrylamide Application, Amrakh I. Mamedov, Chi-Hua Huang, Fazil A. Aliev, Guy J. Levy

Biology Publications

Understanding the effects of soil intrinsic properties and extrinsic conditions on aggregate stability is essential for the development of effective soil and water conservation practices. Our objective was to evaluate the combined role of soil texture, aggregate size and application of a stabilizing agent on aggregate and structure stability indices (composite structure index [SI], the and n parameters of the VG model and the S-index) by employing the high energy (0-5.0 J kg(-1)) moisture characteristic (HEMC) method. We used aggregates of three sizes (0.25-0.5, 0.5-1.0 and 1.0-2.0 mm) from four semi-arid soils treated with polyacrylamide (PAM). An increase in SI …

Functional Traits Of Expanding, Thicket-Forming Shrubs: Contrasting Strategies Between Exotic And Native Species, Sheri A. Shiflett, Julie C. Zinnert, Donald R. Young

Biology Publications

Woody expansion has been documented for decades in many different systems globally, often yielding vast changes in ecosystem functioning. While causes and consequences of woody expansion have been well documented, few studies have addressed plant functional traits that promote dramatic and rapid expansion in range. Our objectives were to investigate plant functional traits that contribute to the colonization, rapid expansion, and thicket formation of an invasive, N-fixing shrub, Elaeagnus umbellata Thunb. (Elaeagnaceae), and a native, N-fixing shrub Morella cerifera (L.) Small (Myricaceae) and compare to native, sympatric, non-expanding shrub species. Quantified functional traits included morphological (e.g., specific leaf area, leaf …

Minion™ Nanopore Sequencing Of Environmental Metagenomes: A Synthetic Approach, Bonnie L. Brown, Mick Watson, Samuel S. Minot, Maria C. Rivera, Rima B. Franklin

Biology Publications

Environmental metagenomic analysis is typically accomplished by assigning taxonomy and/or function from whole genome sequencing or 16S amplicon sequences. Both of these approaches are limited, however, by read length, among other technical and biological factors. A nanopore-based sequencing platform, MinION™, produces reads that are ≥1 × 104 bp in length, potentially providing for more precise assignment, thereby alleviating some of the limitations inherent in determining metagenome composition from short reads. We tested the ability of sequence data produced by MinION (R7.3 flow cells) to correctly assign taxonomy in single bacterial species runs and in three types of low-complexity synthetic communities: …

Ibrutinib In Combination With Sorafenib Synergistically Inhibits Proliferation And Survival Of Hepatocellular Carcinoma Cells By Targeting Egfr Signaling Pathway, Cho-Hao Lin, Nissar Wani, Khadija Elkholy, Kalpana Ghoshal

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

The Scaffolding Protein Iqgap1 Promotes Hepatic Proliferation And Protects The Liver From Injury, Hanna Erickson, Sayeepriyadarshini Anakk

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Commonly Used H1 And H2 Histamine Receptor (Hr) Blockers Decrease Cholangiocarcinoma Xenograft Tumor Growth, Angiogenesis And Emt, Lindsey Kennedy, Laura Hargrove, Jennifer Demieville, Walker Karstens, Steven Smith, Heather Francis

Hepatobiliary Cancers: Pathobiology and Translational Advances

No abstract provided.

Code For "Noise-Enhanced Coding In Phasic Neuron Spike Trains", Cheng Ly, Brent D. Doiron

Statistical Sciences and Operations Research Data

This zip file contains Matlab scripts and ode (XPP) files to calculate the statistics of the models in "Noise-Enhanced Coding in Phasic Neuron Spike Trains". This article is published in PLoS ONE.

Biophysical Drivers Of Carbon Dioxide And Methane Fluxes In A Restored Tidal Freshwater Wetland, Ellen Stuart-Haëntjens, Scott C. Neubauer, William Shuart, Christopher M. Gough

Rice Rivers Center Research Symposium

Wetlands store large amounts of carbon (C) in biomass and soils, playing a crucial role in offsetting greenhouse gas (GHG) emissions; however, they also account for 30% of global yearly CH4 emissions. Anthropogenic disturbance has led to the decline of natural wetlands throughout the United States, with a corresponding increase in created and restored wetlands. Studies characterizing biogeochemical processes in restored forested wetlands, particularly those that are both tidal and freshwater, are lacking but essential for informing science- based carbon management.

Identifying Biotic Determinants Of Historic American Eel (Anguilla Rostrata) Distributions, Taylor E. Woods, Daniel J. Mcgarvey

Rice Rivers Center Research Symposium

Traditionally, ecologists studying large scale patterns in species distributions emphasize abiotic variables over biotic interactions. Noting that both abiotic & biotic variables likely determine distributions of all organisms, many ecologists now aim for a more comprehensive view of species distributions, inclusive of both abiotic and biotic components (Soberón 2007).

Evolution Of Protein Complexes In Bacterial Species, Shwetha Hara Sridhar, Wedad Albalawi, Peter Uetz

UROP Posters

Protein complexes are composed of two or more associated polypeptide chains that may have different functions. Protein complexes play a critical role for all processes in life and are considered as highly conserved in evolution. In previous studies, protein complexes from E. coli or Mycoplasma pneumoniae have been characterized experimentally, revealing that a typical bacterial cell has on the order of 500 protein complexes. Using gene homology (orthology), these experimentally-observed complexes can be used to predict protein complexes across many species of bacteria. Surprisingly, the majority of protein complexes is not conserved, demonstrating an unexpected evolutionary flexibility.

The current research …

Meta-Analysis Of The Origin Of Bimaturism In Orangutan Males, Mina Adnan

UROP Posters

Unlike any other primate species, orangutans exhibit extraordinary sexual differences in their facial morphology. Two different strategies are available for males that reach sexual maturity: either become fully “flanged” and develop secondary sexual characteristics, which is knownto be only developed by the dominant male, or remain “unflanged” and not develop secondary sexual characteristics. The mechanism for how this bimaturism evolved and how occurs is poorly understood, but both flanged and unflanged males are reproductively successful.

This project explores the physiological mechanism behind bimaturismin orangutan males; namely, are there genetic differences between flanged and unflanged males such that the strategy is …

Separation Of Blood Mixtures Using Fluorescently Labeled Antibodies, Christopher Ehrhardt, Dani Jabado, Emily Brocato

UROP Posters

Identifying and analyzing biological mixture samples at a crime scene are of paramount concern for forensic scientists, especially if that type of evidence contains only one cell type. The presence of multiple contributors in a biological evidence sample reduces the probative value of DNA evidence and can sometimes lead to its eventual loss of value. As such, this study was performed in an attempt to examine and evaluate flow cytometry analysis as a means to separate blood mixture samples labeled with fluorescent antibodies. Fluorescein Isothiocyanate (FITC) antibodies were specifically targeted and bound to HLA (Human Leukocyte Antigens) markers present on …

Hydrogen Sulfide Regulation Of Kir Channels, Junghoon Ha

Theses and Dissertations

Inwardly rectifying potassium (Kir) channels establish and regulate the resting membrane potential of excitable cells in the heart, brain and other peripheral tissues. Phosphatidylinositol- 4,5-bisphosphate (PIP2) is a key direct activator of ion channels, including Kir channels. Gasotransmitters, such as carbon monoxide (CO), have been reported to regulate the activity of Kir channels by altering channel-PIP2 interactions. We tested, in a model system, the effects and mechanism of action of another important gasotransmitter, hydrogen sulfide (H2S) thought to play a key role in cellular responses under ischemic conditions. Direct administration of sodium hydrogen sulfide (NaHS), as an exogenous H2S source, …

The Influence Of Genetic And Environmental Factors On Quit Attempt In Adolescent And Young Adult Twins, Gladys Langi

Theses and Dissertations

The purpose of this study was to examine the genetic and environmental influences on lifetime quit attempt in three US adolescent and young adult twin samples (N total = 6,322). The study utilized a common-contingent-causal (CCC) model to estimate these factors for lifetime quit attempts, after accounting for the factors for lifetime cigarette use and cigarettes per day. The study also examined age and sex differences, as well as the degree of relationship between these smoking phenotypes. The results demonstrated significant genetic influences for lifetime quit attempts in adolescents and young adults. No sex differences were observed for the contributions …

Three Dimensional Homology Modeling Of Organic Cation Transporter 3 To Identify Structural Elements Mediating Transporter-Substrate Interactions, Hebing Liu

Theses and Dissertations

Organic cation transporters (OCTs) play a pivotal role in the absorption, tissue distribution, and excretion of a diverse array of substances, and currently the nature of the biochemical interactions between substrate and OCTs are unknown. Therefore, identifying which amino acid residues are critical for OCT-substrate interactions is of central importance to understanding and predicting interactions between drugs and OCTs. A three-dimensional (3-D) homology model of human OCT3 was generated using the crystal structure of a high affinity phosphate transporter from Piriformospora indica (PiPT) as template, and putative binding pocket for the prototypical hOCT3 ligand 1-methyl-4-phenylpyridinium (MPP⁺) was identified …

Ethanol Reversal Of Oxycodone Tolerances, Joanna C. Jacob

Theses and Dissertations

Oxycodone is a semi-synthetic opioid originally developed as a safer alternative to morphine. It is commonly prescribed for its pain-relieving effects, but has recently been implicated as a major underlying cause of the current opioid epidemic due to its clinical limitations that include tolerance, dependence and a high abuse liability. Simultaneous consumption of opioids and ethanol has been shown to increase the risk of overdose and death from opioids in opioid-tolerant individuals. We hypothesized that ethanol reversed opioid tolerance and previous studies showed that ethanol reversed morphine tolerance. This dissertation investigated whether ethanol reversed tolerance to other opioids in mice, …

Short-Term Effects Of Nutrients On A Barrier Island Grassland Community, Ashley Moulton

Theses and Dissertations

Increased nutrient availability globally has the potential to affect community functional composition of plants in nutrient limited environments, such as coastal grassland systems. Stability of these systems are threatened worldwide by urbanization, as well as effects of sea level rise and increased frequency and intensity of storms, and atmospheric N deposition, associated with climate change. Annual net primary productivity (ANPP), species composition, and functional traits (community weighted specific leaf area (CWSLA), leaf area index (LAI), growth form and photosynthetic pathway) were measured across four treatments to assess multiple resource limitation of nitrogen (N) and phosphorus (P) and functional community response …

Effects Of Prescribed Fire On Cope’S Gray Treefrog (Hyla Chrysoscelis) Across Habitat Scales And Life Stages, Logan Mcdonald

Theses and Dissertations

Fire may alter both aquatic and terrestrial habitat used by all amphibian life stages, yet, our knowledge of its effects on amphibians is primarily limited to adult responses. I present an integrated approach to test the response of Cope’s Gray Treefrog (Hyla chrysoscelis) to fire by examining responses in tadpole performance and survivorship, adult abundance, and oviposition. Tadpoles raised with burned leaf litter had similar survival, but total mass and total length were 440% and 170% greater, respectively, for tadpoles raised in unburned litter. I assessed terrestrial and aquatic oviposition cues by embedding burned and unburned litter treatments within burned …

Novel Role Of The Nociceptin System As A Regulator Of Glutamate Transporter Expression In Developing Astrocytes, Logan Meyer

Theses and Dissertations

Our previous results showed that oligodendrocyte development is regulated by both nociceptin and its G-protein coupled receptor, the nociceptin/orphanin FQ receptor (NOPR). The present in vitro and in vivo findings show that nociceptin plays a crucial conserved role in both human and rodent brain astrocytes, regulating the levels of the glutamate/aspartate transporter GLAST/EAAT1. This nociceptin-mediated response takes place during a critical developmental window that coincides with astrocyte maturation and synapse formation. GLAST/EAAT1 upregulation by nociceptin is mediated by NOPR and the downstream participation of a complex signaling cascade that involves the interaction of several kinase systems, including PI-3K/AKT, mTOR and …

Contribution Of A Class Ii Ribonucleotide Reductase To The Manganese Dependence Of Streptococcus Sanguinis, John L. Smith

Theses and Dissertations

Manganese-deficient Streptococcus sanguinis mutants exhibit a dramatic decrease in virulence for infective endocarditis and in aerobic growth in manganese-limited media. Loss of activity of a manganese-dependent, oxygen-dependent ribonucleotide reductase (RNR) could explain the decrease in virulence. When the genes encoding this RNR are deleted, there is no growth of the mutant in aerobic broth culture or in an animal model. Testing the contribution of the aerobic RNR to the phenotype of a manganese transporter mutant, a heterologous class II RNR from Lactobacillus leichmannii called NrdJ that requires B₁₂ rather than manganese as a cofactor was previously introduced into an …

Deletion Of Cardiac Mir-17-92 Cluster Increases Ischemia/ Reperfusion Injury Via Pten Upregulation, Meeta B. Prakash

Theses and Dissertations

The miR-17- 92 cluster is necessary for cell proliferation and development of the cardiovascular system. Deletion of this cluster leads to death in neonatal mice. The role of this cluster still needs to be defined following ischemia and reperfusion. Methods and Results: Adult male mice were injected with Tamoxifen- was to induce inducible cardiac-specific miR-17- 92-deficient (miR-17- 92-def: MCM:TG:miR-17- 92 flox/flox ) and wild type (WT: MCM:NTG:miR-17-92 flox/flox ) mice were subjected to 30 minutes of myocardial ischemia via left anterior descending coronary artery ligation followed by reperfusion for 24 hours. Post I/R survival (48%) and ejection fraction were reduced, …

Role Of Mir-155 And Mir-146a In Mast Cell Function, Amina Abdul Qayum

Theses and Dissertations

Mast cells are resident immune cells abundantly found in the tissue at the host-environment interface, where they play a critical role in inflammatory allergic responses. Mast cell responses may be regulated by the cytokine milieu at the site of inflammation. Recent studies have revealed microRNAs to be important in altering cytokine signaling in immune cells. Here, we demonstrate for the first time that IL-10 and IL-33 induce miR-155 and miR-146a, respectively, to alter mast cell functions. We report that IL-10 enhanced IgE induced activation of mast cells. IL-10 effects are dependent on Stat3 activation, which elicits miR-155 expression, resulting in …

Type 2 Immune Responses In The Context Of Helminth Infection, Asthma, Dendritic Cells, And Myeloid Derived Suppressor Cell Function, Sheela Ruby Damle

Theses and Dissertations

Type 2 (T_H2) immune responses evolved to respond to helminth parasite infections by the production of T_H2 cytokines, which stimulate anti-helminth immunity. Macrophage migration inhibitor factor (MIF) is a pleiotropic cytokine, which is produced by many cell types. We demonstrate that mice deficient in MIF have enhanced clearance of a helminth parasite. MIF deficiency in CD4⁺ T cells was found to be the most important for mediating parasite clearance. We mimicked MIF deficiency by administering an inhibitor of the MIF tautomerase activity, sulforaphane, and this also increased parasite clearance (Section I).

T_H2 immune …

Hub Proteins, Paralogs, And Unknown Proteins In Bacterial Interaction Networks, Neha Sakhawalkar

Theses and Dissertations

Proteins are the functional units of cells. However, a major portion of the proteome does not have a known functional annotation. This dissertation explores protein -protein interactions, involving these uncharacterized or unknown function proteins. Initially, protein – protein interactions were tested and analyzed for paralogous proteins in Escherichia coli. To expand this concept further and to get an overview, protein – protein interactions were analyzed using ‘comparative interactomics’ for four pathogenic bacterial species including Escherichia coli, Yersinia pestis, Vibrio cholerae and Staphylococcus aureus. This approach was used to study unknown function protein pairs as well as to …

Role Of Mitochondrial Beta-Oxidation In Ethanol Response: A Candidate Gene Study Using Caenorhabditis Elegans, Harini Pallikarana Tirumala

Theses and Dissertations

Alcohol use disorder (AUD) is the fourth leading cause of preventable death in the United States, and the fifth leading risk factor for premature death and disability, globally. There are currently very few treatment options for AUD and there is a need for effective preventive and treatment strategies for this condition. AUD risk has a significant hereditary component, with the contribution of genetic factors being estimated to be about 50%. The Davies-Bettinger laboratory uses C. elegans as a model organism to study the contribution of genetic factors in modulating neuronal responses to ethanol. In this project, we examined the role …

Sh3 And Multiple Ankyrin Repeat Domain 3 (Shank3) Affects The Expression Of Hyperpolarization-Activated Cyclic Nucleotide-Gated (Hcn) Channels In Mouse Models Of Autism, Nikhil N. Shah

Theses and Dissertations

SH3 and multiple ankyrin repeat domains 3 (SHANK3) is a multidomain scaffold protein that is highly augmented in the postsynaptic density (PSD) of excitatory glutamatergic synapses within the central and peripheral nervous systems. SHANK3 links neurotransmitter receptors, ion channels, and other critical membrane proteins to intracellular cytoskeleton and signal transduction pathways. Mutations in SHANK3 are linked with a number neuropsychiatric disorders including autism spectrum disorders (ASDs). Intellectual disability, impaired memory and learning, and epilepsy are some of the deficits commonly associated with ASDs that result from mutations in SHANK3. Interestingly, these symptoms show some clinical overlap with presentations of human …

Po2 Dependence Of Oxygen Consumption In Skeletal Muscle Of Hypertensive And Normotensive Rats, Habiba Shah

Theses and Dissertations

Human essential hypertension affects over 75 million people in the United States, and can lead to death due to its several serious health complications such as hypertension-related cardiovascular disease. The purpose of this research was to understand how hypertension could cause physiological changes to the microcirculation, specifically the PO₂ dependence of oxygen consumption (VO₂) in skeletal muscle of normotensive and hypertensive rats. The Spontaneously Hypertensive Rat (SHR) strain was used as the diseased model, and Wistar-Kyoto (WKY) rats were used as controls to conduct this study. The SHR strain develops hypertension between 5-6 weeks after birth with …

Persistence Of The Larval Environment On Post-Metamorphic Performance And Population Dynamics In Amphibians, Julie Charbonnier

Theses and Dissertations

Organisms with complex life cycles may experience diverse stressors during their development. Stressors experienced in early life stages may influence the quantity and quality of individuals in later life stages. However, it is unclear if these effects persist later in life and how they may influence population dynamics. This dissertation uses two amphibian species, the Western spadefoot toad (Pelobates cultripes) and the spotted salamander (Ambystoma maculatum) to explore how biotic and abiotic factors experienced in aquatic and terrestrial environments influence phenotype and survival. We use a combination of field mesoscosm studies, laboratory studies and modeling to …

Effects Of Silencing Cyc2-Like Genes On Floral Development In Solanum Lycopersicum L. And Nicotiana Obtusifolia M. Martens & Galeotti (Solanaceae), Joonseog Kim

Theses and Dissertations

CYCLOIDEA (CYC) and DICHOTOMA (DICH) of the CYC2 clade of the TCP gene family have been shown to play a significant role in regulating the identity of the dorsal petals and abortion of the single dorsal stamen in Antirrhinum majus. It is believed that CYC2-like genes are responsible for the convergent evolution of floral zygomorphy, but their role in the development of actinomorphic flowers is still unknown. In Solanaceae, previous analysis has identified two paralogs of CYC2-like genes, CYC2A and CYC2B, resulting from a gene duplication that predates the origin the family. …