Life Sciences Commons^™

Walleye Trophic Position Before And After A Gizzard Shad Extirpation, Bethany J. Bethke, Justin A. Vandehey, Mark J. Fincel, Brian D.S. Graeb, Mark T. Porath

The Prairie Naturalist

Walleye (Sander vitreus) are an ecologically and recreationally important sport fish species. Reduced growth and condition in walleye can occur when prey availability is limited. In two Nebraska reservoirs, walleye consumed gizzard shad (Dorosoma cepedianum) as their primary prey until a winterkill extirpated the gizzard shad in 2001. Because of the winterkill, walleye in the two reservoirs had to change to alternative prey items. Our objective was to determine if stable isotope analysis on archived walleye scales can be used to detect a known food web shift in two reservoir food webs. We quantified the changes …

Avian Diversity And Habitat Use On Wetland Reserve Program Lands In The Lower Missouri River Valley, Eric C. Hopps

The Prairie Naturalist

A primary objective of the Wetland Reserve Program (WRP) is to provide habitat for migratory birds throughout all seasons of the year. Comprehensive avian assessments are lacking and limit our ability to evaluate the benefits of the WRP to continental bird populations. I investigated avian species occurrence on WRP lands within the Lower Missouri River Valley (LMRV), Nebraska, USA, from March 2010 to February 2011. Ten WRP habitat types are described based on plant community assemblages and observed hydrological regimes. Estimates of avian species richness were greatest in lowland forest (n = 115), lowland woodland (n = 83) and upland …

Index To Volume 80

Nebraska Bird Review

Addy, Darren 47, 75

Albrecht, Jeff 75

Albright, Patty 111

Allen, Edward 128

Allison, Scott 28, 48

American Ornithologists' Union 120

Anderson, Leif 129

Anthony, Courtney 75

Armknecht, Henry 88

Arnett, Gladys 128

Avocet, American 54, 79, 93, 137

. . .

Wren: Bewick's 99; Carolina 13, 36–37, 63, 99, 110, 147, 161; House 63, 81, 99, 106–110, 147; Marsh 13, 36-37, 63, 81, 99, 147, 161; Rock 63, 99, 119, 147; Sedge 63, 81, 99, 108, 147; Winter 13, 36–37, 63, 147, 160

Wright, Rick 48

Yellowlegs: Greater 10, 54, 93, 137, 160; Lesser 46, 54, 79, 93, 137 …

Glutaredoxin 2 (Grx2) Knockout Increases Sensitivity To Oxidative Stress In Mouse Lens Epithelial Cells, Hongli Wu, Liren Lin, Frank Giblin, Ye-Sheh Ho, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

Glutaredoxin belongs to the oxidoreductase family with cytosolic glutaredoxin 1 (Grx1) and mitochondrial gluraredoxin 2 (Grx2) isoforms. Of the two isozymes, the function of Grx2 is not well understood. This paper studied the effect of Grx2 deletion on cellular function using primary lens epithelial cell cultures isolated from Grx2 gene knockout (KO) and wild type (WT) mice. We found that both cell types showed similar growth patterns and morphology, and comparable mitochondrial glutathione pool and complex I activity. Cells with deleted Grx2 did not show affected Grx1 or thioredoxin (Trx) expression but exhibited high sensitivity to oxidative stress. Under treatment …

Subscription And Organization Information [December 2012]

Nebraska Bird Review

The Nebraska Bird Review is published quarterly by the Nebraska Ornithologists' Union, Inc., as its official journal, and is sent to members not in arrears of dues. Annual subscription rates (on a calendar-year basis only): $15 in the United States, $18 in Canada and $30 in all other countries, payable in advance. Single copies are $4 each, postpaid, in the United States, $5 in Canada, and $8 elsewhere. Send orders for back issues to Anita Breckbill, NOU Librarian, c/o Music Library, WMB 30, University of Nebraska, Lincoln, NE 68588-0101 (or at the email address listed below).

Memberships in the NOU …

Winter Ecology Of Sandhill Cranes (Grus Canandensis) In Northern Mexico, Ingrid Barcelo

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

Sandhill Cranes (Grus canadensis) are a widespread species in North America and one of the most studied cranes in the world. However, most of the research has focused on the breeding grounds of Canada and Alaska and the staging grounds of Nebraska. Although an important proportion of the Mid-continent Population of Sandhill Cranes winters in northern Mexico, little information exists on distribution, status, and ecology of the species in Mexico. The goal of this dissertation was to provide new information on Sandhill Crane winter ecology from a regional perspective to better understand population trends. I examined the physiological …

Conservation Genetics Of A Spotted Salamander (Ambystoma Maculatum (Shaw 1802)) Local Population In Southeast Tennessee, Daniel Scott Armstrong

Masters Theses and Doctoral Dissertations

Currently there is a worldwide amphibian decline with numerous causes. Because of this, it is important to understand how genetic variation in local amphibian populations is affected by disturbance. The goal of this study was to assess the genetic impacts of past chemical and ammunition storage and present industrialization on a local population of Ambystoma maculatum (Shaw 1802) using thirteen microsatellite markers. Most loci exhibited no loss of heterozygosity but the low effective population size may indicate vulnerability to future declines. No population substructure or sex-biased dispersal was detected. Possible explanations for the reduction in genetic diversity at four loci …

Effects Of Obesity On Thermoregulation And Cardiovascular Function During Exercise In Females, Jon David Adams

Graduate Theses and Dissertations

Previous research has shown that obese individuals are at greater risk for heat illnesses because of impaired thermoregulation. However, laboratory studies investigating cardiovascular and thermoregulatory function in obese individuals are difficult to interpret because of low sample sizes and methodological concerns. The purpose of this study was to determine if there are differences in thermoregulatory and cardiovascular function between obese and non-obese females. Twenty-four females, 13 obese (43.3 ± 4 .3 % fat, 77.2 ± 13.7 kg) and 11 non-obese (27.8 ± 6.0 % fat, 55.7±6.7 kg), cycled for 60 min in a warm environment (~40°C, 30% humidity) at a …

Breeding For Modified Seed Composition In Soybean: Selection Of Genotypes, Yield Stability, And Environmental Effects, Luciano Miguel Jaureguy

Graduate Theses and Dissertations

The development of cultivars with modified seed composition represents an excellent alternative to cope with the world's need for more nutritious food. Understanding the genetic and environmental factors controlling crop seed quality traits is of crucial importance for such an endeavor. The objectives of this study were: a) to evaluate the efficiency of phenotype and marker-assisted selection for low stachyose and low phytate soybean breeding lines, and their yield stability, b) to study the effect of management practices planting date and delayed harvest on soybean seed composition, and c) to study the potential association between soil properties and leaf chemical …

Capillary And Microchip Electrophoresis For The Monitoring Of Disease Causing Amyloid Proteins, Elizabeth Nancy Pryor

Graduate Theses and Dissertations

The detection of oligomers and aggregates formed by two amyloid proteins, insulin and amyloid-beta (AB), is of particular importance due to the role which these species play in Diabetes and Alzheimer's disease, respectively. However, existing techniques are limited in the ability to detect insulin and AB; oligomers due to the fact that these early aggregates are transient, present at low concentrations, and difficult to isolate. Improvements must be made to existing techniques or alternative techniques must be explored in order to identify and quantify the size of these oligomeric and aggregate species without disrupting their structure.

Capillary and microchip electrophoresis …

Effects Of Felled Shortleaf Pine (Pinus Echinata Mill.) Moisture Loss On Oviposition Preferences And Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Jessica Hartshorn

Graduate Theses and Dissertations

The European woodwasp, Sirex noctilio F. (Hymenoptera: Siricidae) utilizes pine as its host during larval development. Females drill through pine bark to deposit eggs, a symbiotic fungus, Amylostereum, and phytotoxic mucus into the tree. In their native range, these insects are not viewed as primary pests because they attack dead or dying trees. Over the last century, this woodwasp has been accidentally introduced into several countries in the southern hemisphere. Some regions have incurred millions of dollars in damage to large plantations of the widely planted pine species, radiata pine (Pinus radiata D. Don). Sirex noctilio was discovered …

Influence Of Nutritional Modifications On Sow, Litter, And Nursery Performance, Benjamin Edward Bass

Graduate Theses and Dissertations

Two separate series of experiments were conducted to determine: 1) the influence of dietary arginine supplementation in late gestation on reproductive performance, and 2) the impact of a whole yeast product in gestation, lactation, and weaned pig diets on reproductive, growth, and immune parameters.

In the first study 99 sows were provided a control diet, or the control diet supplemented with 1% L-arginine from gestation d 93 to 110. Compared to control-fed sows, no differences were observed in reproductive parameters, however a tendency for increased gestational weight gain was observed for sows provided supplemental arginine.

In a second study, 98 …

The Impact Of Bovine Spongiform Encephalopathy (Bse) On World Protein Supply, Jarrod Kersey

Graduate Theses and Dissertations

As world population, per capita income and urbanization increase, consumption of meat, poultry, milk and eggs will continue to rise to meet the needs of approximately nine billion people in 2050. Global beef, pig and chicken production and per capita consumption increased between 2000 and 2010, with growth in broiler production and consumption outpacing both beef and swine. The increased production and consumption requires readily available feed ingredients in regions where animal production is rapidly developing. Animal-based protein feed ingredients are often difficult to move from country to country due to real or perceived risk of animal disease. Zoosanitary standards …

Alternative Herbicide Control Options For Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri), George Macmillan Botha

Graduate Theses and Dissertations

The occurrence of glyphosate-resistant (GR) Palmer amaranth has prompted a shift in weed management strategies worldwide. Studies were conducted with the aim to (1) establish and compare the degree of tolerance of GR Palmer amaranth populations; (2) assess the efficacy of glufosinate, tembotrione, 2,4-D or dicamba, applied alone or tank-mixed, on Palmer amaranth with higher tolerance to glufosinate in the greenhouse and corn field, and (3) establish the mechanism involved in the tolerance of Palmer amaranth to glufosinate. Tembotrione, 2,4-D, dicamba, and glufosinate applied at 1x controlled 80 to 100%, 98 to 100%, 84 to 100%, and 94 to 100% …

Habitat Modeling Of Three Endemic Crayfish Species In The Black River Drainage Of Missouri And Arkansas: Factors Affecting Distribution And Abundance, Matthew Stephen Nolen

Graduate Theses and Dissertations

The Ozark faunal region of Missouri and Arkansas harbors a high level of aquatic biological diversity, especially in regards to endemic crayfish. Orconectes eupunctus, Orconectes marchandi, and Cambarus hubbsi are three such endemics that are threatened by a limited natural distribution and the invasions of Orconectes neglectus. I sought to determine how natural and anthropogenic factors influence these three species across multiple spatial scales. Local and landscape data were used in decision tree analyses (CART) to determine their influence effect on presence/absence and density of the three species. Predictive models were validated using k-fold cross validation. O. eupunctus presence was …

Phenotypic Plasticity Of Rattlesnake Trophic Morphology, Matthew Thomas Smith

Graduate Theses and Dissertations

The trophic morphology of gape-limited predators constrains the shape and size of prey items they can ingest. Trophic morphology consists of any morphological feature that is involved in the handling and ingestion of food. Diet has a profound effect on the morphology of many gape-limited predators. Identifying how prey type and resource level affect the morphology of different populations is an essential step in understanding the mechanisms contributing to patterns of morphological diversity. Species interactions (Chapter 1) induce plasticity in morphology that can lead to increased fitness, morphological divergence, and eventually speciation.

In Chapter 2, a laboratory study tested the …

Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga

Graduate Theses and Dissertations

Positive associations among species have contributed to the maintenance of biodiversity. These interactions are typically studied in pairwise fashion where two interacting organisms are the focus. This dissertation uses network theory to analyze positive plant-ant associations in three Neotropical forests. Obligate plant-ant mutualisms were used, where plants host the ants in domatia and provide food bodies while the ants protect the plants and can feed them. A network approach was used to depict all obligate plant-ant interactions within a community. The main questions asked at the community level were: 1) Do network structure and levels of specialization change geographically and, …

Stress-Adaptation And Stress-Induced Changes In Campylobacter Jejuni, Geetha Sanal Kumar-Phillips

Graduate Theses and Dissertations

The foodborne pathogen Campylobacter jejuni is one of the leading causes of human gastroenteritis. This bacterium is not a robust organism compared with many other foodborne pathogens and requires special conditions in the laboratory for its growth. In nature, however, this organism is able to survive in very diverse and hostile environments and produce disease in humans. The different mechanisms by which C. jejuni survives stressful conditions in the environment remain unclear. Adhesion and invasion are thought to be important factors for the colonization of C. jejuni in the intestinal tracts of hosts. Previous research in our laboratory showed that …

The Biological Control Of Spotted Knapweed In The Southeastern United States, Carey R. Minteer

Graduate Theses and Dissertations

Spotted knapweed is an invasive, short-term-perennial plant that is native to Eurasia. It was accidentally introduced into North America in the early 1890's and has since spread across The United States and Canada. Spotted knapweed degrades rangelands and pastures by negatively impacting native plants, increasing soil surface runoff and stream sediment yields, and reducing soil infiltration. A biological control program for spotted knapweed using Larinus minutus (Coleoptera: Curculionidae), was initiated in Arkansas in 2008. In this dissertation I described the releases of L. minutus and investigated the adult activity in the southeastern United States (Chapter 1), investigated the effects of …

Life History Variation Of Common Terns In The Gulf Of Maine, Jeffery Bryant Kimmons

Graduate Theses and Dissertations

Life history is the inheritable rules that determine energy and time allocation towards different competing functions in the energy budget of an organism. Reproductive effort varies as organisms make reproductive decisions based on available energy. Factors influencing life histories are those that change energy and time budgets such as diet, competition, and environmental conditions.

Common tern (Sterna hirundo) life history phenotypes vary between islands in the Gulf of Maine. Common terns on offshore islands (>10km from mainland) and nearshore islands (5 to 10km from mainland) lay smaller clutches, hatching chicks with slower growth rates than common terns …

Effect Of Heat Treatments On The Properties Of Two Long-Grain Rice Cultivars During Storage, Youngbum Lee

Graduate Theses and Dissertations

During storage, the milling and physicochemical properties and eating quality of rice change, which is generally termed `aging'. Aged rice is preferred by processors, and there are attempts to develop accelerated aging process using various heat sources. In this study, the effects of various heat treatments and their influence on the milling, pasting, thermal, and cooking properties of two long-grain rice cultivars during storage were investigated using a full-factorial experimental design. Two long-grain rice cultivars, Wells and XP723, was treated with 8 different heat treatments including one control and stored at room temperature for 180 days. Heat treatments included 2 …

Effects Of Associated Subcortical Beetles On Oviposition Behavior And Early-Stage Survival Of Sirex Nigricornis F. (Hymenoptera: Siricidae), Ace J. Lynn-Miller

Graduate Theses and Dissertations

Sirex (Hymenoptera: Siricidae) woodwasps develop within xylem of host conifers. Sirex females drill through the bark, phloem and into xylem tissues where they deposit eggs along with a symbiotic Amylostereum fungus. The presence of Amylostereum is necessary for successful development of Sirex immatures as the larvae are unable to derive adequate nutrition from xylem in the absence of the fungus. The Eurasian woodwasp, Sirex noctilio F., was discovered in northeastern North America in 2004. Sirex noctilio has caused significant economic damage in Pinus radiata D. Don plantations of the southern hemisphere, but is of little economic significance in its native …

The Role Of Centromeric Chromatin And Kinetochore-Associated Factors In Chromosome Segregation, Wesley Williamson

Graduate Theses and Dissertations

Previous work in our lab has identified a point mutation in HTA1, one of the genes encoding histone H2A, which causes an increase-in-ploidy phenotype in Saccharomyces cerevisiae. This histone mutant strain was used to carry out a transposon insertion screen to identify suppressors of the increase-in-ploidy phenotype. This screen identified all three subunits of the Hda histone deacetylase complex, HDA1, HDA2, and HDA3. This study aims to elucidate the function of the Hda complex in chromosome segregation by exploring interactions among the members of the complex, as well as interactions between Hda complex and kinetochore components. …

Timing Of Castration, With Or Without Analgesia, On Growth Performance, Hematology, And Behavior Of Beef Calves, April C. Brown

Graduate Theses and Dissertations

Angus-sired (n = 30) and Hereford-sired (n = 32) bull calves were assigned randomly to 1 of 4 treatments. Treatments were 1) surgical castration near birth, 2) oral administration of the analgesic meloxicam (1 mg/kg of body weight) followed by surgical castration near birth, 3) surgical castration at weaning, or 4) surgical castration at weaning with oral administration of the analgesic meloxicam (1 mg/kg of body weight). Data was recorded for behavior, hematology, and growth at birth and weaning. Calf standing and lying activity was monitored at both stages by recording x and y axis positions of a data logger …

Characterization Of Starch By Vibrational Spectroscopy, Brandon H. Holder

Department of Food Science and Technology: Dissertations, Theses, and Student Research

To develop a dispersive Raman spectroscopic method for measuring amylose-amylopectin ratios of corn starch mixtures, 67 mixtures were prepared by randomly mixing waxy and normal corn starches. Amylose contents were measured using a dual wavelength iodine binding colorimetric method. Raman data were collected from 250 to 3200 cm^-1 using optimized instrument parameters. Partial least-squares (PLS) and principal components regression (PCR) were used to prepare multivariate calibration models; however, PLS commonly outperformed PCR. Truncating the spectra to 250 to 2000 cm^-1 improved the results (r² of validation = 0.831, SEP = 2.90%). Removal of a cold water swelling …

Energy Development And Conservation Of Sympatric Wildlife: New Approaches To Meet Growing Challenges, William Christian Dunn

Biology ETDs

Conflicts between energy development and conservation of sympatric wildlife are becoming more acute as demand for energy increases. Resolving these conflicts is complex-- solutions must address the role of location, scale, and connectivity in persistence of populations. In Chapter 1, I use the MaxEnt species distribution model and pertinent climate variables to predict the natural distribution of the Lesser Prairie Chicken (LPC) (Tympanuchus pallidicinctus), a prairie grouse adversely affected by habitat loss from energy development. Within the geographic range of LPC, precipitation was strongly associated with its distribution in the north, whereas temperature was strongly associated with its distribution in …

Effects Of Climate Change Upon Birds In The Mojave And Sonoran Deserts, Harinamsimran Kaur Khalsa

Biology ETDs

Climate change has increasingly become an area of concern in relation to ecological communities. In this study, climatic signals were investigated to determine whether bird diversity indices in the Breeding Conservation Region (BCR) of the Mojave and Sonoran Deserts were related (1) to the oceanic/atmospheric systems El Nino Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), and/or the Atlantic Multidecadal Oscillation (AMO); (2) to regional moisture influences determined by the Palmer Drought Severity Index (PDSI); and (3) to local precipitation and temperature. Specifically, an examination was conducted to determine the relationship between climatic variables for thirteen bird species, total abundance …

Genetic Diversity, Local Differentiation, And Adaptive Evolution In Introduced Populations Of The Invasive Plant Isatis Tinctoria L. (Brassicaceae), Heather L. Simpson

Biology ETDs

Populations of invasive species are often characterized as genetically depauperate, an inherent consequence of the colonization process. It has also been suggested that species that are able to avoid these reductions in genetic diversity may be better able to adapt to their introduced range. Evolutionary change can play an important role in the invasion process if novel selective pressures drive adaptive evolution. Species that are able to avoid reductions in genetic diversity associated with colonization may be better able to adapt to their introduced range. To better understand the genetic processes following invasion, introduced populations of the invasive mustard, Isatis …

Lno Network Sites Data Training Needs, Long Term Ecological Research Network

Long Term Ecological Research Network

Partial memo answering the following questions.

Does your site have any training needs that are not being covered by the training activities organized by the LNO?

Do you have any questions about the All Scientists Meeting?

Compared to the other 25 LTER sites, how prepared will you be by December 31, 2012 to provide site data to the Network Information System via PASTA, top quarter of all sites, second quarter; third quarter; bottom quarter?

Treatment Thresholds For Bollworm (Helicoverpa Zea) In Dual-Gene Bt Cotton, Kristen Carter

All Theses

Dual-gene Bt cotton has reduced the need for insecticide treatments for bollworm, Helicoverpa zea (Boddie), compared with original single-gene Bt technology. Bollgard II¨ (Monsanto, St. Louis, MO) and WideStrike¨ (Dow AgroSciences, Indianapolis, IN), both produce the Cry1Ac protein and a second protein, Cry2Ab or Cry1F, respectively. These dual-gene Bt cottons provide enhanced control of lepidopteran pests, but remain less than 100% effective against bollworm, particularly when population pressure is high. Current recommended treatment thresholds for bollworm on cotton in South Carolina are as follows: treat with insecticides when three or more large larvae are found per 100 plants or when …