Life Sciences Commons^™

Nanoparticle Toxicity And Molecular Mechanisms In Fish: A Case Study With Silver Nanoparticles, Jiejun Gao

Open Access Dissertations

Nanoparticles (NPs) are widely used in a myriad of commercial and industrial products making their entry to the environment a likely event. NPs have unique physical-chemical properties that result from their small size and high surface area to volume ratio, making them highly reactive and potentially toxic. In Chapter 1, we summarize the effects and mechanisms of metal-based NPs on the vascular system. In vitro studies have shown that NPs are anti-angiogenic because they cause inflammation, oxidative stress, and apoptosis of endothelial cells resulting in increased permeability and decreased proliferation and migration. Whole animal studies examining the effects of NPs …

Syk Promotes Tgf-Beta-Induced P-Body Clearance In Breast Cancer Cells Through The Enhancement Of Autophagy, Shana D. Hardy

Open Access Dissertations

SYK is a protein tyrosine kinase that plays an essential role in the development and activation of immune cells. Its expression, however, is not limited to immune cells. SYK is expressed in a variety of epithelial cell types and epithelial-derived tumors. Reports regarding the role of SYK expression in these diverse cell types and tumors have been opposing. In breast cancer, SYK expression has been overwhelmingly associated with tumor suppression. The loss of Syk expression is observed in invasive breast carcinoma tissue and cell lines and the reintroduction of Syk into metastatic breast cancer cells suppresses tumor growth and metastasis. …

Modeling For Thermal Resistance Of Non-O157 Shiga Toxin Producing Escherichia Coli In Ground Beef, Jagpinder S. Brar

Open Access Dissertations

Predictive models in microbiology are used for estimating the growth or survival of microorganism in a set of environmental conditions. A validated predictive model provides an alternative to extensive survival and shelf life studies. In this study, a predictive inactivation model for non-O157 shiga toxin producing Escherichia coli (STEC) in ground beef was developed. Six strains of non-O157 STEC; E. coli O26:H1, E. coli O45:H2, E. coli O103:H2, E. coli O111:H8, E. coli O121:H9, and E. coli O145: nonmotile, has similar pathogenicity as E. coli O157:H7 and can cause serious food borne illnesses. These pathogens are considered as an adulterant …

Gonadal Intersex In Teleosts: Mechanisms, Molecular Biomarkers And Diagnostic Assays, Ahmed M.E. Abdel-Moneim Mohamed

Open Access Dissertations

Natural and synthetic estrogenic and androgenic compounds are continuously released into aquatic ecosystems. Exposure of teleost fishes to these contaminants can negatively impact sex differentiation and reproductive output. Specifically, development of gonadal intersex in gonochoristic (fixed sex) fish species has been studied extensively in relation to exposure to this class of compounds. The main objectives of this dissertation were to: 1) conduct field and laboratory studies to investigate the molecular signaling pathways behind the development of gonadal intersex; and 2) establish molecular biomarkers and assays for testing the ability of environmental pollutants to develop this condition using a battery of …

Functional And Structural Characterization Of The Mevalonate Diphosphate Decarboxylase And The Isopentenyl Diphosphate Isomerase From Enterococcus Faecalis, Chun-Liang Chen

Open Access Dissertations

Enterococcus faecalis causes a diverse range of nosocomial infections (in wounds, the gastrointestinal tract, the blood stream and the endocardium), and multidrug-resistant strains have become a serious issue across countries. Vancomycin, a FDA-approved drug for the disruption of the bacterial cell wall biosynthesis, has been utilized to treat infectious diseases caused by Enterococci; however, the prevalence of vancomycin-resistant enterococci (VRE) threatens communities all over the world. We aim at developing novel therapeutic strategies to control bacterial growth of Enterococci, and we focus on targeting two essential enzymes involved in poly-isoprenoid biosynthesis in Enterococcus faecalis; one is the mevalonate diphosphate decarboxylase …

Functional Diversity Enhances Detection Of Ecosystem Stability And Resolution Of Predator-Prey Interactions Within A Multitrophic Community, Ashley Lorraine Kissick

Open Access Dissertations

Habitat fragmentation and loss are principal factors that contribute to the decline of biodiversity which in turn has a negative impact on ecosystem function. There has been growing interest in understanding diversity’s role in the mechanisms behind ecosystem resilience with much attention focusing on how functional diversity, or the range of species’ ecological roles in a community, impacts ecosystem function. Under the functional insurance hypothesis, stability in ecosystems is maintained by species that perform similar functions but have asynchronous responses to disturbance. There are three proposed stability mechanisms that operate through species’ asynchronous responses: cross-scale resilience, response diversity, and density …

Quantifying Terrestrial Ecosystem Carbon Dynamics With Mechanistically-Based Biogeochemistry Models And In Situ And Remotely Sensed Data, Shaoqing Liu

Open Access Dissertations

Terrestrial ecosystem plays a critical role in the global carbon cycle and climate system. Therefore, it is important to accurately quantify the carbon dynamics of terrestrial ecosystem under future climatic change condition. This dissertation evaluates the regional carbon dynamics by using upscaling approach, mechanistically-based biogeochemistry models and in situ and remotely sensed data.

The upscaling studies based on FLUXNET network has provided us the spatial and temporal pattern of the carbon fluxes but it fails to consider the atmospheric CO2 effect given its important physiological role in carbon assimilation. In the second chapter, we consider the effect of atmospheric CO2 …

Managing Bacterial Wilt, Caused By Erwinia Tracheiphila, On Muskmelon With Early Control Of Striped Cucumber Beetle ( Acalymma Vittatum (F)), And Through Varietal Selection, Ahmad Shah Mohammadi

Open Access Dissertations

Muskmelon (Cucumis melo L), is an important vegetable crop in the United States. It is grown throughout the US, and Indiana ranked 4th in production after California, Arizona and Georgia with 12.4 thousand metric tons and market value of $7.6 million in 2015. Bacterial wilt of cucurbits, which is caused by Erwinia tracheiphila (E. F. Smith), and vectored by striped cucumber beetle (Acalymma vittatum (F)), is one of the most serious diseases of muskmelon that influences muskmelon quality and yield. Many cultivars of muskmelon are grown around the United States, especially in the Midwest. Muskmelon cultivars differ in …

Bayesian Causal Inference Of Cell Signal Transduction From Proteomics Experiments, Robert D. O. Ness

Open Access Dissertations

Cell signal transduction describes how a cell senses and processes signals from the environment using networks of interacting proteins. In computational systems biology, investigators apply machine learning methods for causal inference to develop causal Bayesian network models of signal transduction from experimental data. Directed edges in the network represent causal regulatory relationships, and the model can be used to predict the effects of interventions to signal transduction. Causal inference approaches applied to proteomics experiments use statistical associations between observed signaling protein concentrations to infer a causal Bayesian network model, but there is no experimental and analysis framework for applying these …

Investigating The Effects Of Ph On Alphaviral E3-E2 Glycoprotein Association, Organization, And Cellular Tropism, Jason Michael Sequra

Open Access Dissertations

In alphaviruses the role of E3 is required in protecting the fusion peptide region of E1 during intracellular transport. Throughout viral processing, the association of E2 and E3 is required for the successful trafficking and incorporation of E1 into the mature virion. This E3-E2 association has been observed to extend to mature virions in the solved structure for the envelope of Semliki Forest virus (SFV) and supported by the solved structure for the entire Venezuelan equine encephalitis virion (VEEV) with exclusive contacts being made between E3-E2. Immunization with monoclonal antibodies against VEEV E3 provided protection for mice challenged by lethal …

The Biology And Management Of Palmer Amaranth (Amaranthus Palmeri S. Wats) In Indiana, Douglas J. Spaunhorst

Open Access Dissertations

Palmer amaranth is a pernicious summer annual weed that has evolved resistance to six herbicide sites of action in the U.S. and threatens agriculture production. In 2011, Palmer amaranth was identified in flood plains in two southern Indiana counties (Posey and Vanderburgh). Determining if Palmer amaranth can survive and reproduce in northern Indiana may provide insight if this weed will be problematic for northern row crop producers. The objectives of our research were to identify fields containing Palmer amaranth and determine the distribution of herbicide resistance traits in Indiana; determine the influence of tillage frequency and tillage intervals on Palmer …

The Role Of Seed Attributes In Eastern Gray Squirrel Foraging, Mekala Sundaram

Open Access Dissertations

Seed attributes are important predictors of rodent foraging behaviors. I examined the role of seed attributes in eastern gray squirrel (Sciurus carolinensis) foraging behavior from an evolutionary, economic, ecological and biochemical perspective. From an evolutionary perspective (chapter 2), I found that squirrel foraging behaviors are influenced by a combination of phylogenetically conserved and evolutionarily labile seed traits, which supports a diffuse coevolutionary relationship between hardwood trees and squirrels and provides indirect evidence supporting the Janzen-Connell and handling time hypotheses. From an economic perspective (chapter 3), I found that eastern gray squirrels are homogenous with respect to their preferences for seed …

Improving And Elucidating Factors Regulating Black Walnut (Juglans Nigra L.) Clonal Propagation, Micah E. Stevens

Open Access Dissertations

Black walnut (Juglans nigra L.) is a fine hardwood tree species native to the central hardwood region of the United States. High-quality black walnut timber is highly desirable. Traded in both regional and global markets, it has been used for veneer, and the manufacture of high-end products such as cabinets, furniture, and gunstocks. As a result of its high economic value, black walnut has been commercially cultivated for many years, and breeding programs have generated superior timber genotypes with improved marketable traits. Once elite genotypes were developed, it was quickly recognized that black walnut was recalcitrant to clonal propagation …

Characterizing The Effects Of Repetitive Head Trauma In Female Soccer Athletes For Prevention Of Mild Traumatic Brain Injury, Diana Otero Svaldi

Open Access Dissertations

As participation in women’s soccer continues to grow and the longevity of female athletes’ careers continues to increase, prevention of mTBI in women’s soccer has become a major concern for female athletes as the long-term risks associated with a history of mTBI are well documented. Among women’s sports, soccer exhibits the highest concussion rates, on par with those of men’s football at the collegiate level. Head impact monitoring technology has revealed that “concussive hits” occurring directly before symptomatic injury are not predictive of mTBI, suggesting that the cumulative effect of repetitive head impacts experienced by collision sport athletes should be …

Dynamic Regulation Of Dna Demethylation And Rna-Directed Dna Methylation In Arabidopsis, Kai Tang

Open Access Dissertations

DNA methylation is an important epigenetic mark present in many eukaryotes, and is involved in many crucial biological processes, such as gene imprinting, regulation of gene expression, and genome stability. Proper genomic DNA methylation patterns are achieved through the concerted action of DNA methylation and demethylation pathways. In the model plant species Arabidopsis thaliana, ROS1 (REPRESSOR OF SILENCING 1) is one of the DNA demethylases and the key component in the demethylation pathway. Dysfunction of ROS1 leads to increase in DNA methylation level at thousands of genomic loci. However, the features of ROS1 targets are not well understood. In the …

Repurposing Non-Antimicrobial Drugs To Treat Multi-Drug Resistant Bacterial And Fungal Infections, Shankar Thangamani

Open Access Dissertations

Bacterial and fungal resistance to conventional antimicrobials is a burgeoning global health epidemic that necessitates urgent action. Even more alarming, the development of new antimicrobials to treat these multidrug-resistant pathogens has not kept pace with the rapid emergence of resistance to current antimicrobials. Antimicrobial drug development through the traditional de novo process is a risky venture given the significant financial and time investment required by researchers and limited success rate of translating these compounds to the clinical setting. This has led researchers to mine existing libraries of clinical molecules in order to repurpose old drugs for new applications (as antimicrobials). …

The Relationship Between Protein And Phosphorus Digestion And Retention In Growing Pigs And Broiler Chickens, Pengcheng Xue

Open Access Dissertations

Xue, Pengcheng. Ph.D., Purdue University, December 2016. The Relationship between Protein and Phosphorus Digestion and Retention in Growing Pigs and Broiler Chickens. Major Professor: Dr. Layi Adeola. The objective of this study was to investigate the relationship between protein and P digestion and retention in growing pigs and broiler chickens. The methodology of determining the digestibility of AA and P and the effect of dietary N and P on the digestion and retention of these two nutrients were investigated.

An experiment was conducted in growing pigs to investigate the additivity of AID or SID of CP and AA in mixed …

The Effects Of Dietary Probiotic Inclusion On Skeletal Health Of Poultry And Its Possible Mechanisms, Feifei Yan

Open Access Dissertations

Probiotics are live microorganisms which may confer health benefits on the host when administered in appropriate amounts. Numerous studies have shown that probiotics improve bone health in humans and rodents with less information available on the skeletal health of avians given probiotics. The objective of this study was to determine the effects of probiotic supplementation on bone health of egg-laying and meat-type chickens. Dietary supplementation of a multi-species based probiotic reduced the percentage of shell-less eggs beginning at 4 wk following treatment and increased tibial and femoral bone mineral density in egg-laying hens at 7 wk post-treatment. Similarly, bone mineralization …

Mechanistic Insight Into The Role Of Dietary Fibers And Short Chain Fatty Acids In The Regulation Of Metabolism And Inflammation In The Pig, Hui Yan

Open Access Dissertations

Dietary fiber is a diverse mixture of polysaccharides exerting multiple functions as it passes through the gastrointestinal tract (GIT). Besides the influence on nutrient digestibility, dietary fiber affects growth performance and host metabolism via modulation of gut microbial community structure and production of short chain fatty acids (SCFA). A series of in vivo experiments were conducted to determine the effects of dietary fiber on pig growth performance and gut microbial community as well as host metabolism. In the first study, a comparison between soluble and insoluble fibers was conducted in terms of pig growth, gut microbial structure and SCFA production …

Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean Powers, C. Edward Proffitt, Nicolle Rutherford, Camille L. Stagg, Keith Walters

Biology

Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent …

Multilayered Structure Of Tension Wood Cell Walls In Salicaceae Sensu Lato And Its Taxonomic Significance, Barbara Ghislain, Eric-André Nicolini, Raïssa Romain, Julien Ruelle, Arata Yoshinaga, Mac H. Alford, Bruno Clair

Faculty Publications

Salicaceae have been enlarged to include a majority of the species formerly placed in the polyphyletic tropical Flacourtiaceae. Several studies have reported a peculiar and infrequently formed multilayered structure of tension wood in four of the tropical genera. Tension wood is a tissue produced by trees to restore their vertical orientation and most studies have focused on trees developing tension wood by means of cellulose-rich, gelatinous fibres, as in Populus and Salix (Salicaceae s.s.). This study aims to determine if the multilayered structure of tension wood is an anatomical characteristic common in other Salicaceae and, if so, how its …

Tlr8 Couples Socs-1 And Restrains Tlr7-Mediated Antiviral Immunity, Exacerbating West Nile Virus Infection In Mice, Amber M. Paul, Dhiraj Acharya, Linda Le, Penghua Wang, Dobrivoje S. Stokic, A. Arturo Leis, Lena Alexopoulou, Terrence Town, Richard A. Flavell, Erol Fikrig, Fengwei Bai

Faculty Publications

West Nile virus (WNV) is a neurotropic ssRNA flavivirus that can cause encephalitis, meningitis, and death in humans and mice. Human TLR7 and TLR8 and mouse TLR7 recognize viral ssRNA motifs and induce antiviral immunity. However, the role of mouse TLR8 in antiviral immunity is poorly understood. In this article, we report that TLR8-deficient (Tlr8−/−) mice were resistant to WNV infection compared with wild-type controls. Efficient WNV clearance and moderate susceptibility to WNV-mediated neuronal death in Tlr8−/− mice were attributed to overexpression of Tlr7and IFN-stimulated gene-56 expression, whereas reduced expression of the proapoptotic gene coding Bcl2-associated X protein was observed. …

Running Decreases Knee Intra-Articular Cytokine And Cartilage Oligomeric Matrix Concentrations: A Pilot Study, Robert D. Hyldahl, Alyssa Evans, Sunku Kwon, Sarah T. Ridge, Eric Robinson, J. Ty Hopkins, Matthew K. Seeley

Faculty Publications

Introduction Regular exercise protects against degenerative joint disorders, yet the mechanisms that underlie these benefits are poorly understood. Chronic, low-grade inflammation is widely implicated in the onset and progression of degenerative joint disease.

Purpose To examine the effect of running on knee intra-articular and circulating markers of inflammation and cartilage turnover in healthy men and women.

Methods Six recreational runners completed a running (30 min) and control (unloaded for 30 min) session in a counterbalanced order. Synovial fluid (SF) and serum samples were taken before and after each session. Cytokine concentration was measured in SF and serum using a multiplexed …

The Effects Of High Concentrations Of Ionic Liquid On Gb1 Protein Structure And Dynamics Probed By High-Resolution Magic-Angle-Spinning Nmr Spectroscopy, Lisa Warner, Erica Gjersing, Shelby E. Follett, K. Wade Elliott, Sergei V. Dzyuba, Krisztina Varga

Biomedical Research Institute Publications and Presentations

Ionic liquids have great potential in biological applications and biocatalysis, as some ionic liquids can stabilize proteins and enhance enzyme activity, while others have the opposite effect. However, on the molecular level, probing ionic liquid interactions with proteins, especially in solutions containing high concentrations of ionic liquids, has been challenging. In the present work the ¹³C, ¹⁵N-enriched GB1 model protein was used to demonstrate applicability of high-resolution magic-angle-spinning (HR-MAS) NMR spectroscopy to investigate ionic liquid–protein interactions. Effect of an ionic liquid (1-butyl-3- methylimidazolium bromide, [C₄-mim]Br) on GB1was studied over a wide range of the ionic liquid …

Plant Community Composition And Structure Monitoring For Scotts Bluff National Monument, 2016 Data Report, Molly B. Davis, Daniel J. Swanson

United States National Park Service: Publications

Abstract

This report presents the results of vegetation monitoring efforts in 2016 at Scotts Bluff National Monument (SCBL) by the Northern Great Plains Inventory and Monitoring Network (NGPN) and Northern Great Plains Fire Ecology Program (NGPFire).

During the sixth full year of field work, crew members from NGPN visited eight long-term monitoring plots on May 23-25, 2016 to collect data on the plant communities at SCBL. This is part of a long-term monitoring effort to better understand the condition of the vegetation at SCBL. NGPN staff captured data relating to species richness, herb-layer height, abundance of individual native and non-native …

Plant Community Composition And Structure Monitoring For Agate Fossil Beds National Monument, 2016 Data Report, Aaron T. Rasor, Daniel J. Swanson

United States National Park Service: Publications

Abstract

This report presents the results of vegetation monitoring efforts in 2016 at Agate Fossil Beds National Monument (AGFO) by the Northern Great Plains Inventory and Monitoring Network (NGPN).

During the sixth full year of field work, crew members from NGPN visited six long-term plant community monitoring (PCM) plots and the Northern Great Plains Fire Effects Crew (NGPFire) visited nine fire plant community monitoring (FPCM) plots to collect data on the plant communities at AGFO. This effort is part of a long-term monitoring program established to better understand the condition of the mixed-grass prairie, riparian, and upland regions in AGFO. …

Distribution, Abundance, And Migration Timing Of Greater And Lesser Sandhill Cranes Wintering In The Sacramento–San Joaquin River Delta Region Of California, Gary L. Ivey, Bruce D. Dugger, Caroline P. Herziger, Michael L. Casazza, Joseph P. Fleskes

Proceedings of the North American Crane Workshop

The Sacramento-San Joaquin River Delta region of California (hereafter, Delta region) is an important wintering region for the Central Valley Population of greater sandhill cranes (Grus canadensis tabida) and lesser sandhill cranes (G. c. canadensis), but basic information about the ecology of these birds is lacking to design a biologically sound conservation strategy. During the winters of 2007-08 and 2008-09, we conducted roost counts, roadside surveys, aerial surveys, and tracked radio-marked birds to define the geographic area used by sandhill cranes in the Delta region, document migration chronology, and estimate subspecies-specific abundance. Radio-marked sandhill cranes arrived in our study area …

Timber Talk, Vol. 54, No. 4, December 2016

Timber Talk: Nebraska Forest Industry Newsletter

In This Issue

Lumber Market Reports 1

Hardwood Lumber Prices 2

Note from the Editor - EAB Meeting Discussion 3

THE CHALLENGE - Using Forest Residues from Forest Operations 4

2016 Tax Tips Bulletin Available 4

Nebraska Forest Industry Spotlight 5

Alaska Airlines’ first flight with biofuel made from forest residuals 7

The Four “P’s” of Marketing Your Small Sawmill Business 7

Trading Post 8

60 | ‘Akko Ii: The 1991–1998 Excavations: The Early Periods, Moshe Hartal, Danny Syon, Eliezer Stern, Ayelet Tatcher

IAA Reports—Monograph Series of the Israel Antiquities Authority

chapter 1. `Akko-Ptolemais - a maritime city at the crossroads of ancient civilizitions until Roman times / Nadav Kashtan -- part I. Excavations at the courthouse site. chapter 2. The courthouse site: architecture and stratigraphy of areas TB and TC / Moshe Hartal -- chapter 3. The courthouse site: the glass from areas TB and TC / Natalya Katsnelson -- chapter 4. The courthouse site: loomweights and whorls / Orit Shamir -- part II. Excavations in the Hospitaller compound. chapter 5. The Hospitaller compound: Hellenistic and early Roman remains / Eliezer Stern -- chapter 6. The Hospitaller compound: Hellenistic and …

Willingness To Pay For Irrigation Water Under Scarcity Conditions, Tyler Robert Knapp

Graduate Theses and Dissertations

Reliance of Arkansas agricultural producers on groundwater for irrigation has led to depletion of the Mississippi River Valley alluvial aquifer. Without intervention, consequences include insufficient groundwater to meet irrigation demand as well as drawdown of the deeper Sparta Aquifer, upon which communities in eastern Arkansas rely for non-agricultural use. Among proposed solutions to combat groundwater decline is the construction of off-farm surface water infrastructure to meet the irrigation needs of producers. Despite the importance of irrigated agriculture to Arkansas, there is little know about the economic value of irrigation water to producers. Thus, we implement a double-bounded dichotomous choice contingent …