Life Sciences Commons^™

Molecular And Biochemical Mechanisms Of Pathogenesis In The Maize Foliar Pathogen Cercospora Zeae-Maydis, Winfred-Peck Dorleku

Graduate Theses and Dissertations

GLS is a serious foliar disease of maize, a major staple crop grown commercially in the USA for both human and animal feed production, and increasingly, for ethanol production. The disease is caused by two Cercospora species, C. zeae-maydis and C. zeina, both of which infect maize in the USA and in other parts of the world, with yield losses potentially greater than 50%, depending on local conditions. In culture, C. zeae-maydis produces a phytotoxic, host non-specific perylenequinone, cercosporin, and abscisic acid (ABA), for which there is no known pathological or physiological function in the fungus. Experimental evidence indicates …

Bacterially-Mediated Formation Of Rock Coatings In Kärkevagge, Swedish Lapland: A Mineralogical And Micro-Environmental Analog For Mars, Cassandra L. Marnocha

Graduate Theses and Dissertations

The search for past or present life on Mars is, for now, limited to surface environments. An often neglected surface environment that could have served as an abode for life and could presently preserve evidence of that life is that of rock coatings. Rock coatings are mineral accretions on rock surfaces. On Earth, they are widespread and occur with considerable chemical diversity. There is growing evidence for a biotic role in their formation on Earth, particularly with respect to rock varnish. As a result, rock varnish has become a target of astrobiological interest on Mars, where varnish-like coatings have been …

The Effect Of Calcium And Nonphytate Phosphorus On Chicken Genetic Line, Egg Production, Shell Quality, Bone Homeostasis, And Progeny Bone Quality, Phiphob Sodsee

Graduate Theses and Dissertations

The study consisted of two parts to determine effects of dietary calcium (Ca) and nonphytate phosphorus (NPP) level on four pure genetic lines of broiler breeders. The first part was concentrated on body composition, egg production and shell quality changes according to diet and genetic line. The second part was the study of bone homeostasis variables combining hematology, bone histology and body composition changes according to diet and genetic line. In the study, pullets (246 from each of pure genetic line A, B, C and D) were individually caged and light stimulated at 21 weeks of age. The study duration …

Long-Term Residue And Water Management Effects On Soil Respiration And Soil Aggregate Stability In A Wheat-Soybean, Double-Crop System In Eastern Arkansas, Sharon Faye Smith

Graduate Theses and Dissertations

Sustainability in agriculture is paramount to assuring continued production from our most naturally fertile soils. Storing carbon (C) in soil as organic matter through sustainable agricultural management practices can both remove atmospheric C and improve soil quality. The objective of this study was to evaluate the long-term effects of water management (irrigation and dryland), residue management [burn and no-burn, conventional (CT) and no-tillage (NT)] and residue/fertility level (high and low) on soil respiration and aggregate stability in a wheat- (Triticum aestivum L.) soybean [Glycine max (L.) Merr.], double-crop system in a silt-loam soil (Aquic Fraglossudalf) in the Mississippi River Delta …

Prescribed Fire On Public Lands, Wesley G. Page, Michael R. Kuhns

All Current Publications

This fact sheet helps readers understand prescribed fire planning and implementation on public lands.

Helping Children Understand And Manage Anger, Shannon Cromwell, Naomi Brower

All Current Publications

Anger is a strong emotion that often leads to negative coping strategies. Children's anger poses challenges for parents and other caregivers and accounts for stress and frustration. Engaging children in a variety of effective coping strategies can assist with their feelings of anger.

Are We Running Out Of Phosphorus?, Nayda Gonzalez, Rhonda Miller

All Current Publications

Phosphorus is an essential nutrient. The world’s phosphorus supplies are limited. Do we have enough phosphorus to support our needs? This fact sheet addresses this question.

Permaculture, Roslynn Brain, Blake Thomas

All Current Publications

No abstract provided.

Transcriptomic Analyses Of The Co2-Concentrating Mechanisms And Development Of Molecular Tools For Chlamydomonas Reinhardtii, Andrew J. Brueggeman

Department of Biochemistry: Dissertations, Theses, and Student Research

Microalgae, such as Chlamydomonas reinhardtii, account for a large percentage of photosynthesis that occurs on the planet. Many algae possess a Carbon-Concentrating Mechanism, or CCM, that actively transports inorganic carbon (C_i) into the cell to create artificially high internal levels of CO₂, enhancing their rate of carbon fixation. The production of biofuels from algal sources can serve as both a renewable and carbon-neutral energy source. This thesis details research in Chlamydomonas, in the effort to both better understand the CCM in algae and improve laboratory and industrial manipulations with algae.

In the first chapter of this …

Population Occurrence And Pathogen Prevalence Of Lone Star Ticks (Acari: Ixodidae) Collected From Southeast Nebraska, Amanda C. Maegli

Department of Entomology: Dissertations, Theses, and Student Research

Lone star tick, Amblyomma americanum (L.), has recently become established in Nebraska; therefore, local biology, ecology, and tick-borne disease risk are not known. Research was conducted to determine monthly questing activity, establishment, and pathogenic microorganisms associated with the lone star tick in Nebraska.

Lone star tick populations were collected from May through August, 2012 in six sites in southeast Nebraska using carbon dioxide (CO₂) traps. A total of 747 adults, 3,076 nymphs, and 1,289 larvae were collected. Total ticks collected and monthly activity were significantly different for each site.

A semi-randomized sample of 251 adult ticks were selected …

Toxic And Repellent Effects Of Pyrethroids Used In Orchards On The Honey Bee, Apis Mellifera L. (Hymenoptera: Apidae), Erin M. Ingram

Department of Entomology: Dissertations, Theses, and Student Research

Managed honey bee colonies provide valuable pollination services and are rented by fruit orchards to improve fruit quality and yield. The placement of colonies in this agricultural setting increases the possibility of exposure to pyrethroids used for broad-spectrum pest control in orchards. Although highly toxic to bees, pyrethroids are believed to pose a relatively low hazard due to their low application rates in the field as well as their contact repellent properties. Previous studies have noted a decrease in foraging visits following pyrethroid application possibly preventing bees from acquiring a lethal dose in the field.

This research quantified behaviors associated …

Impact Of Wheat Streak Mosaic Virus And Triticum Mosaic Virus On Transmission By Aceria Tosichella Keifer (Eriophyidae) And Virus Epidemiology In Wheat, Camila F. De Oliveira

Department of Entomology: Dissertations, Theses, and Student Research

The wheat curl mite (WCM), Aceria tosichella Keifer, transmits a complex of viruses, Wheat streak mosaic virus (WSMV), Triticum mosaic virus (TriMV) and Wheat mosaic virus (WMoV), to wheat, Triticum aestivum, in the Great Plains. Co-infection of wheat by these viruses is frequently observed, increasing disease severity and yield loss.

Current genetic work classifies WCM populations into two genotypes, Type 1 and Type 2. It has been shown that different mite genotypes are able to transmit viruses at varying rates. WCM-virus relations are very specific and can impact vector biology. In this study, the primary objective was to determine …

Anoxia Tolerance Of Forensically Important Calliphorids, Melissa M. Lein

School of Natural Resources: Dissertations, Theses, and Student Research

Forensically important blow flies, Diptera: Calliphoridae, are among the first organisms to colonize carrion. After eggs hatch, the larvae of most blow fly species feed in an aggregation or “mass.” While in this mass larvae may experience periods of no oxygen (anoxia), little oxygen (hypoxia), or normal oxygen (normoxia), but the tolerance of blow fly larvae to severe hypoxic conditions is not known. I tested the anoxia tolerance of four species of calliphorids (Calliphora vicina, Cochliomyia macellaria, Lucilia sericata, and Phormia regina), using third stage larvae across five temperatures. Experiments were conducted by exposing larvae to pure nitrogen …

A Population Model For Walleye In Nebraska Irrigation Reservoirs, Robert A. Kill

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding how and why fish population size changes between years is a central theme in fisheries ecology. Fishery agencies have limited time and financial resources, thus there is a need for a quantitative way to direct the limited time and financial resources so agencies can manage fisheries more efficiently. I developed a tool for fishery managers that synthesizes common population indices and evaluated the relative importance of those indices given varying uncertainty in age-0 walleye Sander vitreus survival. Under most circumstances, I determined that resources are best utilized in reducing age-0 survival uncertainty when understanding walleye population growth. I applied …

Predicting Invasion Risk Of Non-Native Plants Using A Modified I-Rank Assessment, Justin B. Williams

School of Natural Resources: Dissertations, Theses, and Student Research

Biological invasions are a global problem responsible for native species declines worldwide. Understanding the invasion risk from non-native species is important in establishing management goals and making decisions for managing native ecosystems. Useful modeling methods for quantifying or predicting invasion risk should consider research needs, data availability, and operate at an appropriate scale. I evaluated risk assessment methods towards answering a specific research question; which plant species pose the greatest risk of becoming invasive or having the greatest negative impact in Nebraska? I selected the I-Rank assessment method, which consists of 20 questions grouped into four risk categories or Subranks: …

Determining Scaphirhynchus Sturgeon Population Demographics And Dynamics: Implications For Range-Wide Management, Recovery, And Conservation, Martin J. Hamel

School of Natural Resources: Dissertations, Theses, and Student Research

Sturgeons (Acipenseridae) have experienced world-wide declines as a result of anthropogenic effects such as over-harvest, habitat degradation, altered flow regimes, and pollution. Nearly all European and Asian sturgeon species have experienced population declines and have subsequently been classified as either threatened or endangered. North American sturgeons have experienced a similar plight in that all eight native sturgeon species are listed as endangered, threatened, or of special concern. Direct linkages between North American sturgeon declines and anthropogenic effects are difficult to assess due to scale considerations, fluctuating environmental conditions, difficulty in capture, and the interaction of all these effects. To recover, …

Development Of Food Safety Education And Pilot Study Specifically For Native Americans Audiences, Kristine M. Foley

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

The purpose of this study was to develop and implement a culturally appropriate food safety educational program using the conceptual change teaching method while preparing a meal. The food safety educational program was based on the FightBac!™ concepts (CLEAN, SEPARATE, COOK AND CHILL). Quantitative and qualitative date were collected, compared, and analyzed. Two pilot studies were conducted with Native American participants on non-reservation sites in Omaha and Lincoln. A total of 27 participants completed a pre and post knowledge survey and were video recorded preparing a meal. The majority of the participants were female (78%), had at least a high …

The Development And Applications Of Nmr Metabolomics Analysis Of Bacterial Metabolomes, Steven M. Halouska

Department of Chemistry: Dissertations, Theses, and Student Research

Metabolomics is a relatively new field that involves the study of metabolic responses that are occurring within a biological system. Metabolite profiles of an organism, tissue extract, and biofluids are important indicators to determine the physiological state of a biological profile. Comparison of such profiles from different phenotypes can be used to identify specific metabolic changes leading to the understanding of metabolic pathways, disease progression, drug toxicity and efficacy, and cellular responses to different intracellular and extracellular conditions. Metabolomics investigations often use sophisticated analytical techniques such as NMR spectroscopy to provide an unbiased and comprehensive approach to evaluate metabolic perturbation …

Recombinant Expression, Purification, And Characterization Of An Hiv-1 Tat-Human Cyclin T1 Chimera, Collin Lesley Fischer

Dissertations - ALL

Efficient transcription of the human immunodeficiency virus type 1 (HIV-1) requires the interaction of the viral protein Tat with the trans-activation response (TAR) stem-loop of the long-terminal repeat (LTR) portion of nascent viral RNA. The production of viable transcripts is enhanced dramatically by the interaction of HIV-1 Tat with the host protein human Cyclin T1. Interaction with hCycT1 remodels Tat protein contributing a single cysteine residue that is critical to the formation of the second of two zinc fingers (Zn2). Here we suggest that it is the presence of this critical cysteine residue and not the presence of arginine residues …

Synthesis Of Novel Ciprofloxacin Analogues And Evaluation Of Their Anti-Proliferative Effect On Human Cancer Cell Lines, Narva Suresh, Hunsur Nagendra Nagesh, Kondapalli Venkata Govri Chandra Sekhar, Anil Kumar, Amir Nasrolahi Shirazi, Keykavous Parang

Pharmacy Faculty Articles and Research

A series of twenty two novel 1-cyclopropyl-6-fluoro-4-oxo-7-(4-substitutedpiperazin-1-yl)-1,4-dihydroquinoline-3-carboxylic acid analogues have been synthesized, characterized (1H NMR, 13C NMR and LCMS) and evaluated for their inhibitory activity on the proliferation of human caucasian acute lymphoblastic leukemiacells (CCRF-CEM), breast adenocarcinoma cells (MDA-MB-468) and human colon carcinoma cells (HCT-116). Among all the synthesized ciprofloxacin analogues 3t at 50 µM showed comparable potency to doxorubicin (10mol) in all three cell lines and 3j inhibited proliferation of MDA-MB-468 up to 35% selectively over other two cell lines. Cancer is a leading cause of death worldwide. It is a group of diseases characterized by uncontrolled growth. Cancer …

Research: South Dakota State University, Winter 2013, Christie Delfanian, Matt Landwehr

State of Discovery South Dakota State University's Research Magazine

CONTENTS:

South Dakota expertise integral part of Landsat [Page] 1
West Nile: Researchers help public health officials combat West Nile virus [page] 2
Health care: arteries, corticosteroids, concussions, and preemies [Page] 4
Oilseeds [Page] 6
Undergraduate Research [Page] 8
Organ donation key to helping Native Americans on dialysis [Page] 10
Researchers meet challenge of increased competition: 2012 measurements [Page] 11

Changes In Tissue-Specific Fatty Acid Composition Of The Freshwater Alewife (Alosa Pseudoharengus) In Response To Temperature, William D. Schregel

Biology Theses

Ectotherms are known to alter the composition of the cell membrane in response to changes in environmental temperature. Tissue-specific fatty acid composition in the alewife (Alosa pseudoharengus) was examined in response to both warm and cold temperature challenges administered over an approximate one month period. Gill, muscle, and liver tissues were analyzed prior to the start of the temperature challenge (initial), following the temperature challenges (survivors), and on those fish that did not survive the temperature challenges (mortalities). Significant differences were found between fatty acid composition of initial fish and survivors for membrane-incorporated fatty acids (polar) and for …

The Incidence Of Antibiotic Resistance In Mesophilic Aeromonas Isolated From The Buffalo River And From A Non-Urban Site Upstream, Amy L. Chapman

Biology Theses

Antibiotics are commonly used in agriculture and industry and their discharge is commonly seen in rivers, like the Buffalo River. This antibiotic discharge may cause a selective environment which favors the growth of antibiotic resistant Aeromonas. To study the effect of urban pollution on the antibiotic resistance in Aeromonas, 229 Aeromonas isolates were collected from fish tissues as well as sediment and water samples collected from the Buffalo River and a non-urban site (Cazenovia Creek). Seven different Aeromonas taxa were identified using biochemical tests. There were 124 (54%) isolates that were classified as atypical, which was the most commonly …

Cross Amplification Of Microsatellite Loci Developed For Atractosteus Spatula In Atractosteus Tropicus, Sandra Bohn, Enrique Barraza, Caleb Mcmahan, Brian Kreiser

Faculty Publications

Due to recent population declines in tropical gar (Atractosteus tropicus), a greater understanding of its population structure is needed. A key step in gaining this understanding is the development of microsatellite loci for use in this species. For this purpose, 33 microsatellite loci from alligator gar (A. spatula) were screened in 52 individuals from a population in Zanjón del Chino, El Salvador. Twenty-five of these loci successfully amplified in this species, and 9 of those loci were polymorphic in this population. These loci should provide a useful tool for genotyping A. tropicus, both in studying …

A Test Of Whether Human Handling Causes Developmental Or Habituation Effects On The Hypothalamic-Pituitary-Adrenal Stress Response Of Young American Kestrels (Falco Sparverius), Erin Leigh Wonder

Boise State University Theses and Dissertations

Early exposure to stressors affects subsequent stress responses in both mammalian and avian species, with the likelihood for lasting effects depending, in part, on the magnitude of the stressor. However, it is unclear whether lasting effects are the result of developmental changes to the hypothalamic-pituitary-adrenal (HPA) axis or habituation to the stressor. I investigated the effects of human handling, a known stressor, in free-living American kestrel (Falco sparverius) nestlings to determine if this brief, non-invasive stressor causes lasting changes in the stress response of handled birds, and whether alterations in the stress response were the result of developmental …

Preservice Candidates' Rating Of Effectiveness In Agricultural Education Through Structured Communication With Cooperating Teachers, Christopher Lee Hunt

Graduate Theses and Dissertations

The relationship between cooperating teacher and student has been found as one of the key elements that affect the overall teaching efficacy of student teachers and their decision to enter the teaching field after graduation (Edgar, 2007; Edgar, Roberts, & Murphy, 2011,2008; Kasperbauer et al., 2007a; Roberts, Greiman, Murphy, Ricketts, Harlin, & Briers 2009; Roberts, Harlin, & Briers, 2007, Roberts, Harlin, & Ricketts, 2006; Roberts Mowen, Edgar, Harlin & Briers, 2007, Stripling, Ricketts, Roberts & Harlin, 2008; Wolf, 2011; Wolf et al., 2010). Therefore, determining impacts towards teaching efficacy during the student teaching experience could play a vital role in …

Sex Determination Using Discriminant Function Analysis In Hispanic Children And Adolescents: A Lateral Cephalometric Study, Alyssa E. Sprowl

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lateral cephalometric radiographs have been used for years to help diagnose skeletal and dental patterns in Orthodontics. Within the last decade, these radiographs have caught the interest of the department of Anthropology for the identification of gender within the adult and adolescent population. Numerous publications have been made but failed to identify sexual dimorphism in the pre-adolescent population. 303 lateral cephalograms of pre and post Latino adolescence age ranging from 6.5 to 17.9 years old were obtained from University of Nevada, Las Vegas (UNLV) digital database. 25 variables were identified and plotted with all linear and angular measurements transferred into …

Obstacles And Solutions To Studying Functional Adhesives Using Vibrational Sum-Frequency Generation Spectroscopy, Angela Renee Andersen

Theses and Dissertations

Important aspects of adhesion occur at interfaces, including structures that may be different from those in the bulk materials. However, probing the orientation of molecules in functional adhesives poses a significant challenge because adhesive molecules are always located at a buried interface. The limited penetration depth of surface-specific analysis prohibits the study of buried interfaces using those techniques. The large quantity of bulk molecules relative to the adhesive molecules interacting at the interface results in the bulk signal swamping out adhesive signal in bulk analysis techniques. An interface-specific technique is required to study functional adhesives. One such technique that has …

Endocannabinoid-Dependent Long-Term Depression Of Ventral Tegmental Area Gaba Neurons, Jared Mark Weed

Theses and Dissertations

GABA neurons in the ventral tegmental area of the midbrain are important components in the brain's reward circuit. Long term changes in this circuit occur through the process of synaptic plasticity. It has been shown that high frequency stimulation, as well as treatment with endocannabinoids, can cause GABA neurons in the ventral tegmental area to undergo long term depression, a form of synaptic plasticity that decreases excitability of cells. The present study elaborates on the mechanism whereby high frequency stimulation can result in long term depression of ventral tegmental area GABA neurons. Using the whole cell patch clamp technique in …

Development Of Novel Subunit Vaccine Against H5n1 Influenza, Lu Zhang

Graduate Theses and Dissertations

Influenza is a common infectious disease resulting from a frequently mutated RNA virus. Vaccination is currently the most effective method to prevent people from seasonal or pandemic influenza. The production of traditional egg-based influenza vaccine is time-consuming and provides limited effect against new strains. Therefore, it is necessary to develop a rapid method to produce influenza vaccines. We proposed a novel influenza vaccine based on the E.coli expression system. Hemagglutinin (HA) is the major target surface protein of influenza virus for vaccine development. In this study, we sub-cloned the HAs encoding gene into an E. coli expression vector; the signal …