Life Sciences Commons^™

The Role Of Dksa In The Stringent Response In The Lyme Disease Spirochete Borrelia Burgdorferi, Britney Cheff

Graduate Student Theses, Dissertations, & Professional Papers

Borrelia burgdorferi, the bacterium that causes Lyme disease, is maintained in nature through an enzootic cycle that includes a tick vector and a vertebrate host. The bacterium is acquired by an Ixodes tick from an infected vertebrate. The bacterium alters its gene expression to adapt to different environments of the tick and vertebrate. Between tick feedings, B. burgdorferi must contend with nutrient stress. The stringent response is a physiological mechanism when bacteria switch from “thriving” to “surviving” mode in response to limited nutrient resources; it is mediated by an increase in the nucleotide alarmone guanosine penta- or tetraphosphate, abbreviated …

Community Perturbation Associated With New Zealand Mudsnail (Potamapyrgus Antipodarum) Invasion: Discrepancies In Temporal And Spatial Assessment, Eric H. Richins

Graduate Student Theses, Dissertations, & Professional Papers

Invasive species have the potential to alter the ecosystems within which they establish as well as adjacent but uninvaded ecosystems by altering the flow of nutrients or biota across system boundaries. New Zealand mudsnails (Potamopyrgus antipodarum; NZMS) are often very abundant where they invade, sequestering the majority of stream primary production. This sequestering of production may reduce aquatic insect production, subsequent insect emergence and subsidies to riparian ecosystems. Tetragnathid spiders, an insectivorous riparian specialist, are dependent on the emergence of aquatic insects and are typical indicators of aquatic insect subsidies to riparian zones. In addition, NZMS invasions can result …

Bamboo Harvesting For Household Income Generation In The Ethiopian Highlands: Current Conditions And Management Challenges, Bridget L. Tinsley

Graduate Student Theses, Dissertations, & Professional Papers

Bamboo is a renewable resource that has been advocated as a means to alleviate poverty and foster rural development throughout the world. Ethiopia holds 67% of continental Africa’s bamboo coverage and is gaining interest by international markets. Despite great speculation about Ethiopia’s bamboo market potential, foundational information regarding household utilization and income reliance is lacking. To understand how bamboo contributes to rural Ethiopian households, a quantitative household assessment was undertaken in this study. A questionnaire census collected data from 371 households. A quantitative assessment of household incomes and assets evaluated what factors influence bamboo harvesting.

The contribution of bamboo to …

An Assessment Of Biochar Amended Soilless Media For Nursery Propagation Of Northern Rocky Mountain Native Plants, Clarice P. Matt

Graduate Student Theses, Dissertations, & Professional Papers

A study was conducted to better inform nursery practitioners of the potential benefits of biochar application in common nursery media for native plant propagation. Biochar – a carbon-rich, recalcitrant charred organic co-product of the bioenergy pyrolysis process – has emerged as a promising potential replacement for various components of soilless media, namely peat, perlite, and vermiculite, in nursery seedling propagation. A strong conceptual basis exists for biochar as a nursery media amendment, but empirical data on biochar-based plant propagation is limited. This greenhouse study examined the effects of biochar displacement of standard soilless nursery media at rates of 0%, 15%, …

Cows And Plows: Science-Based Conservation For Grassland Songbirds In Agricultural Landscapes, Marisa K. Lipsey

Graduate Student Theses, Dissertations, & Professional Papers

Temperate grasslands are among earth’s most imperiled ecosystems. In North America, steep declines of endemic songbird populations indicate that grassland loss and degradation may be approaching critical levels. Grasslands are agricultural landscapes largely (~85%) under private ownership with little formal protection status. Remaining bird populations depend on grazing lands that have not been converted to cropland. We combine regional data from a hotspot for grassland bird diversity (northeast Montana, USA; 26,500-km2) with continental data spanning the northern Great Plains (1,000,000-km2) to evaluate how land use and management influence bird distribution and abundance. Regionally, habitat used by seven grassland specialists spanned …

Abundance, Density, And Opinions About Columbian Black-Tailed Deer, Whidbey Island, Washington, Robert P. Wingard

Graduate Student Theses, Dissertations, & Professional Papers

Obtaining reliable knowledge is the first step towards properly managing wildlife species. Columbian black-tailed deer (Odocoileus hemionus columbianus) on Whidbey Island, Washington have not been the subject of study, and little is known about the population, or the opinion of resident’s of Whidbey Island towards the deer population. However, wildlife managers suggest deer on the island may be overabundant or over social carrying capacity. Given the lack of empirical knowledge about the deer population or human opinions towards deer on Whidbey Island, I designed research to determine the abundance and density of Columbian black-tailed deer on Whidbey Island, …

Decadal Scale Responses Of Soil And Ecosystem Processes To Forest Restoration In Rocky Mountain Conifer Forests, Peter Ganzlin

Graduate Student Theses, Dissertations, & Professional Papers

Decades of fire suppression have left much of the forest in the intermountain western United States exceedingly dense, and forest restoration techniques – including thinning and prescribed fire – are increasingly being used in an attempt to mitigate the potentially disastrous effects of severe wildfire, to enhance tree growth and regeneration, and to stimulate soil nutrient cycling. While many of the short-term effects of forest restoration have been established, the long-term effects on soil biogeochemical and ecosystem processes are largely unknown. In this thesis I present two manuscripts documenting and synthesizing these long-term impacts. The first chapter focuses on the …

A Model For Determining Drivers Of Phenology In Western United States Rangelands, Joseph R. St. Peter

Graduate Student Theses, Dissertations, & Professional Papers

Plant phenology has long been used as an indicator of climate. Recent changes in plant phenology are evidence of the influence of climate change. Modeling plant phenology has become an effective tool to understand the impacts of climate change. Using machine learning techniques I developed a modeling process for accurately predicting phenology across a diverse landscape. This model uses individual site data to set site specific climate thresholds for plant phenology. This model also identifies the limiting factors to vegetation phenology for rangelands in the western United States. NDVI remotely sensed data was used to quantify land surface phenology and …

Application Of Supervised Machine Learning Algorithms For Rapid Identification Of Mrsa Pfge Strain Types, Michael L. Bernauer

Biomedical Informatics Seminar Series (BioMISS)

Introduction: Pulsed-field gel electrophoresis (PFGE) is a molecular typing method used in epidemiologic surveillance of MRSA. PFGE relies on electrophoretic migration of restricted DNA fragments, resulting in characteristic fingerprints which can be used to classify organisms. Current methods of analysis, such as Gel Compar II and BioNumerics rely on unsupervised hierarchical clustering algorithms to group organisms based on pairwise similarity. These methods are labor intensive, often requiring a significant amount of user intervention and oversight. This study presents an automated approach to PFGE typing to reduce the amount of user involvement and time required for analysis.

Methods: A total of …

Awareness And Use Of Information And Communication Technology (Ict) Among Farmers In Kerala: A Study, Akshaya Kumar K. S, Dr. Vijayakumar K.P.

Library Philosophy and Practice (e-journal)

Information and Communication Technology (ICT) can be used as a potential tool to develop rural India, but the awareness and positive attitude towards the facilities offered by it is a necessity to use it to the full potential. The study tries to analyze the awareness of farmers about the various ICT tools in agriculture. Survey using questionnaire was resorted to collect data from user group. The user group under consideration consists of farmers registered to four KrishiBhavans in Nedumangad block, Thiruvananthapuram District of Kerala. Farmers with more than 1 acre of land registered in KrishiBhavans in the four selected blocks …

A Framework And System For A Multi-Model Decision Aid For Sustainable Farming Practices, Kasi Bharath Vegesana

Computational Modeling & Simulation Engineering Theses & Dissertations

Decision support systems (DSS) for farmers address the need for modeling multiple processes and scenarios that affect farmer decision making. Existing DSS have various drawbacks that stop them from being deployed as decision support tools. This research proposes a multi-model simulation framework that can be used to analyze farm management practices at the crop level, individual farm level and at the community level to show the impact and alternatives for smallholder farming practices. A generic crop growth model is proposed, based on existing equations. We run sensitivity analysis on the model to identify important variables. The outputs from the crop …

De Novo Protein Structure Modeling And Energy Function Design, Lin Chen

Computer Science Theses & Dissertations

The two major challenges in protein structure prediction problems are (1) the lack of an accurate energy function and (2) the lack of an efficient search algorithm. A protein energy function accurately describing the interaction between residues is able to supervise the optimization of a protein conformation, as well as select native or native-like structures from numerous possible conformations. An efficient search algorithm must be able to reduce a conformational space to a reasonable size without missing the native conformation. My PhD research studies focused on these two directions.

A protein energy function—the distance and orientation dependent energy function of …

Sensitivity Of Cellular Oxidative Damage To Biosynthetic Rate And Metabolic Rate, Palihawadana Walauwe Kamalika Kaushalya Amunugama

Masters Theses

"The relationship between energy expenditure and longevity is a long standing question in aging studies. The empirical results have contradictory effects on the existing theories. A theoretical model and an experimental test of it were presented, revealing the detailed tradeoffs between metabolic rate, biosynthetic rate and cellular damage level. The dissipative mechanisms of oxidative metabolism cause various forms of cellular damages. To counteract the accumulation of damage, organisms have evolved highly efficient maintenance mechanisms. If there is no other energy demand possess, then most of the cellular damage would be repaired, regardless of how metabolic rate varies. However, the repairing …

The Effect Of O Antigen Loss On The Protein Composition And Inflammatory Response Elicited By Klebsiella Pneumoniae, Bethaney Cahill

UNF Graduate Theses and Dissertations

Klebsiella pneumoniae is a Gram-negative pathogen associated with numerous infections. Like all Gram-negative bacteria, K. pneumoniae naturally release outer membrane vesicles (OMVs) during all stages of cellular growth. OMVs are composed of the outer membrane components such as lipopolysaccharide (LPS) and outer membrane proteins and contain cytosolic and periplasmic proteins in the lumen. K. pneumoniae is often found to lack an O antigen. The absence of the O antigen has been reported to alter the protein content of the membrane which may further alter the immune response elicited by K. pneumoniae. Therefore the purpose of this study was to …

Effects Of Prescribed Fire On Upland Plant Biodiversity And Abundance In Northeast Florida, Peter D. Maholland

UNF Graduate Theses and Dissertations

Terrestrial ecosystems in the southeastern United States have evolved with fire as a common disturbance and as a result many natural communities require the presence of fire to persist over time. Human development precludes natural fires from occurring within these communities; however, prescribed fire is considered to be a critical tool in the effort to restore fire-dependent ecosystems after decades of fire exclusion. Direct effects of fire on individual floral and faunal species as well as benefits to biodiversity at the landscape (gamma diversity) level have largely been supported in previous research. However, information on the effects of natural and …

The Reproductive Biology Of The Finetooth Shark, Carcharhinus Isodon, In The Northwest Atlantic Ocean, Amanda N. Brown

UNF Graduate Theses and Dissertations

Shark fisheries are a multimillion dollar industry in the United States and have significant contributions both recreationally and commercially. In order to maintain this industry, fisheries must be properly managed. An understanding of life history and reproduction is crucial in order to adequately manage shark fisheries. The finetooth shark, Carcharhinus isodon, is a member of the small coastal shark (SCS) fishery complex. It is found in Atlantic waters from South Carolina to Florida and throughout the Gulf of Mexico. This species has recently come under increased fishing pressure and has previously been overfished. New data is needed in order …

Characterization Of A Biosynthetic Pathway Yielding Anticancer Natural Products From A Marine Bacterium, Elle D. James

UNF Graduate Theses and Dissertations

Natural products are bioactive secondary metabolites produced by living organisms and are prevalently utilized as pharmaceutical drugs. Marine adapted organisms are a promising source of new natural products possessing unique chemical structures and biological activities. By studying the biosynthetic pathways employed by living organisms to produce natural products, insights into new strategies to generate molecules to combat disease and overcome drug resistance may be gained. This thesis study aimed to uncover the biosynthetic pathway employed by a marine actinomycete, Nocardiopsis sp. CMB-M0232, to catalyze the assembly of the nocardioazines. These molecules are a group of 2,5-diketopiperazine natural products that feature …

Habitat Value Of Restored Intertidal Shoreline For Fish And Macrobenthic Communities In Northeast Florida, Shannon K. Dunnigan

UNF Graduate Theses and Dissertations

Oyster reefs are declining worldwide, as well as the economic and ecological value of oysters to their respective systems. Numerous restoration efforts have been undertaken in hopes of re-establishing these shellfish populations. This study evaluated a restoration project within the Guana Tolomato Matanzas estuary in northeast Florida, U.S.A., to investigate community structure as well as seasonal patterns in species abundance and diversity of juvenile fish and benthic macrofauna within restored and unrestored intertidal habitats along the Guana Peninsula. The first objective was to determine whether the artificially created reefs provided similar quantity and diversity of benthic macrofauna as adjacent unrestored …

Non-Lethal Methods For Assessing Reproductive Status In Bonnethead Sharks (Sphyrna Tiburo), Brenda Carol Anderson

UNF Graduate Theses and Dissertations

Reproductive biology is a necessary element for the management of elasmobranch fisheries. Traditionally, characterization of elasmobranch reproduction has involved lethal sampling to examine gross reproductive structures and development of embryos. However, this method is counterproductive to the conservation of shark populations. One non-lethal alternative is the measurement of serum hormones, which often vary according to reproductive events. Radioimmunoassay (RIA) has been used to measure hormone concentrations in reproductive endocrinology, but can be problematic for researchers. Alternatively, chemiluminescence immunoassays (CLIA) are routinely used for measuring circulating hormone concentrations in low-volume, non-extracted human serum samples. However these assays have not been previously …

Molecular Identification And Functional Characteristics Of Peptide Transporter 1 (Pept1) In The Bonnethead Shark (Sphyrna Tiburo), Hannah Hart

UNF Graduate Theses and Dissertations

Many elasmobranchs are considered top predators with worldwide distribution, and in general these fish play an important role in the transfer of energy from the lower to the upper trophic levels within the marine ecosystem. Despite this, little research has been done regarding the rates of prey ingestion, digestion, and the processes of energy and nutrient absorption. Specifically understudied is enzymatic digestion within the intestinal brush border, which functions to break down macromolecules into smaller subunits for luminal absorption across the gastrointestinal epithelium. Given their carnivorous diet, the present study sought to expand knowledge on nutrient intake in elasmobranchs by …

Sindbis Virus Entry Of Mosquito Midgut Epithelia...Is Nramp Involved?, Florence Yi Ting Chim

UNF Graduate Theses and Dissertations

Sindbis virus (SINV) is an arthropod-borne Alphavirus in the family Togaviridae. Sindbis virus has a broad host range that includes avian, mammalian, and human hosts; therefore, its receptor(s) is/are highly conserved. When the mosquito imbibes a viremic blood meal, the virus infects the midgut cells, disseminates into the hemolymph, and eventually infects the salivary glands. The midgut is an organ of transmission and the virus must overcome the midgut epithelia infection- and escape-barriers. Sindbis virus infection is determined by the chance collision of the glycoproteins with a compatible receptor. Research has supported the involvement of high-affinity laminin receptor and heparan …

Effects Of The Exotic Red Imported Fire Ant (Solenopsis Invicta) On The Growth And Survival Of The Threatened Hooded Pitcher Plant (Sarracenia Minor), Edward Marques

UNF Graduate Theses and Dissertations

Plants and insects are some of the most biodiverse groups in the world and are constantly interacting. One unique interaction that has been observed occurs between carnivorous plants and insects; some plant species are capable of capturing and digesting insects for nutrients. Despite preying on these insects, there are cases where such interactions can been viewed as mutualistic. For instance, a nectar reward is produced by the plant to attract insects, and during visitation insects may fall prey to these plants. Additionally, carnivorous myrmecophytic plants may receive an added indirect benefit in the form of reduced herbivory, since ants have …

Reconciling The Two Cultures : A Case Study Of The University Of Northern Iowa, Elizabeth Ann Collins

Dissertations and Theses @ UNI

In 1959, chemist and author Charles Percy Snow gave a Rede Lecture at the University of Cambridge in which he named “Two Cultures”—the sciences and the humanities—which, according to his experience as someone who worked in both, were at odds with one another. His words elicited impassioned responses from critics who either agreed with Snow, believing this to be a detriment to society, or vehemently disagreed, believing Snow’s statements to be unfounded, and even antagonistic. This conversation, which had also found relevance in the United States, continues to be important today, and has changed over the years as institutions of …

Systematic Study Of The Biological Effects Of Nitric Oxide (No) Using Innovative No Measurement And Delivery Systems, Weilue He

Dissertations, Master's Theses and Master's Reports

Nitric oxide (NO) is recognized as the most important small signaling molecule in the human body. An imbalance of NO is closely associated with many serious diseases such as neurological disorders, cardiovascular diseases, chronic inflammations and cancers. Herein two chemiluminescence-based devices (a real-time NO measurement device and a controllable NO delivery device) were developed to facilitate the NO quantitative study and obtain information for NO related drug design.

The first device used for real-time measuring NO(g) flux from living cells was developed and validated. The principle was to use a two-chamber design, with a cell culture chamber and a gaseous …

Hitchhiking Bats On The Great Lakes Of North America, Saska E.H. Lohi

Dissertations, Master's Theses and Master's Reports

Bats can act as potential vectors for various zoonotic diseases and other pathogens. Therefore their interactions with people should be examined to mitigate potential risks. Bats are small flying mammals and hide in small crevices during daylight hours, making them difficult to observe. Consequently, they have a capacity to “hitchhike” on ships to be dispersed over large distances.

This study focused on anthropogenic unintentional bat translocations, i.e. hitchhiking bats. The study area is the Great Lakes region in North America. Using a web-based questionnaire survey, I asked the public about the frequency of bat-human encounters on ships, their nature, and …

Changes In Carbon Pools Influenced By Changes In Soil Texture, Slope, And Aspect A Decade Following Wildfire In Black Spruce Forests Of Interior Alaska, Gregory Houle

Dissertations, Master's Theses and Master's Reports

Topography and parent material (PM) texture control site drainage owing to changes in water holding capacity, infiltration, and insolation. In turn, these factors also affect fire regime. However, the interactive effects of site physiography, edaphic controls, and wildfire severity on ecosystem carbon accrual after wildfire are poorly understood. Throughout the summer of 2004 an area the size of Massachusetts burned in interior Alaska, and several studies were initiated to investigate the controls on organic layer consumption. In this study we re-sampled organic layer depths, below ground carbon stocks, and site revegetation from 38 burned black spruce sites from the 2004 …

Effects Of N-Acetylcysteine Amide In Preventing/Treating Cataracts, Sri Krishna Yasaswi Maddirala

Doctoral Dissertations

"Cataract, the opacification of an eye lens, is a common pathological abnormality of the lens accounting for approximately 50% of all blindness. The only effective treatment currently available for a cataract is the surgical removal of the affected lens and replacement with an artificial lens for the restoration of vision. Although, cataract surgery is considered to be a very successful procedure in terms of visual outcome, the cost of surgery, need for trained personnel and surgeons, and postsurgical complications, limit the worldwide availability and accessibility of this procedure. Hence, alternative preventive and treatment procedures are worthy of investigation. The lens …

The Acute Effects Of Multiple Resisted Sled-Pull Loads On Subsequent Sprint-Running Performances, Carl Stephen Crouse

Dissertations and Theses @ UNI

Sled-pulling is a commonly implemented form of training for various sports. However, few studies have used sled-pulling as a means of acutely enhancing sprintrunning performances. The purpose of this study was to investigate how various sledpulling resistance loads (95% and 110% of body mass) effect subsequent, unloaded, sprint-running performances, possibly with aid from the effect known as Post-Activation Potentiation (PAP). PAP is a physiological phenomenon which increases the rate of force development of skeletal muscle which may result in the enhancement of power (speed-strength) dominant activities such as sprint-running and jumping.

Participants were a mix of males (n = 11; …

Gender Differences In Social Support During Injury Rehabilitation, Chelsey Ann Bruns

Dissertations and Theses @ UNI

Athletic injury can be a stress-inducing event that could have negative consequences on the psychological health of the athlete (Anderson & Williams, 1988; Gould, Udry, Bridges, & Beck, 1997). Injuries not only challenge the athlete physically, but also mentally challenge their ability to cope and overcome. A growing amount of research has indicated social support as a key factor in the rehabilitation process for an injured athlete (Yang, Peek, Lowe, Heiden, & Foster, 2010). Athletic injury causes an emotional disruption, and social support could influence the athlete’s reaction to the injury and his or her ability to cope with rehabilitation …

How Good Is Good Enough? Data Requirements For Reliable Crop Yield Simulations And Yield-Gap Analysis, Patricio Grassini, Lenny G.J. Van Bussel, Justin Van Wart, Joost Wolf, Lieven Claessens, Haishun Yang, Hendrik Boogaard, Hugo De Groot, Martin K. Van Ittersum, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

Numerous studies have been published during the past two decades that use simulation models to assess crop yield gaps (quantified as the difference between potential and actual farm yields), impact of climate change on future crop yields, and land-use change. However, there is a wide range in quality and spatial and temporal scale and resolution of climate and soil data underpinning these studies, as well as widely differing assumptions about cropping-system context and crop model calibration. Here we present an explicit rationale and methodology for selecting data sources for simulating crop yields and estimating yield gaps at specific locations that …