Life Sciences Commons^™

The Distinctive Bionomics Of Aedes Aegypti Populations In Africa, David P. Tchouassi, Sheila B. Agha, Jandouwe Villinger, Rosemary Sang, Baldwyn Torto

All Peer-Reviewed Publications

Aedes aegypti is the primary vector of dengue, chikungunya, and Zika viruses of medical importance. Behavioral and biological attributes contribute to its vectorial capacity. The mosquito domestic form, which resides outside Africa (Ae. aegypti aegypti (Aaa)), is considered to breed in artificial containers in and around homes and preferentially feeds on human blood but commonly indulges in a plant diet. Potential divergence in these attributes, in sub-Saharan Africa (SSA) where Aaa coexists with the forest ecotype (Ae. aegypti formosus), should impact the vectoring ability and hence disease epidemiology. A summary of current knowledge on Ae. aegypti blood feeding, oviposition, and …

The Possibilities Of Explicit Striga (Striga Asiatica) Risk Monitoring Using Phenometric, Edaphic, And Climatic Variables, Demonstrated For Malawi And Zambia, Emily Kimathi, Bester Tawona Mudereri, Elfatih M. Abdel-Rahman, Saliou Niassy, Henri E.Z. Tonnang, Tobias Landmann

All Peer-Reviewed Publications

Food insecurity continues to affect more than two-thirds of the population in sub‐Saharan Africa (SSA), particularly those depending on rain-fed agriculture. Striga, a parasitic weed, has caused yield losses of cereal crops, immensely affecting smallholder farmers in SSA. Although earlier studies have established that Striga is a constraint to crop production, there is little information on the spatial extent of spread and infestation severity of the weed in some SSA countries like Malawi and Zambia. This study aimed to use remotely sensed vegetation phenological (n = 11), climatic (n = 3), and soil (n = 4) variables to develop a …

Leveraging Machine Learning Tools And Algorithms For Analysis Of Fruit Fly Morphometrics, Daisy Salifu, Eric Ali Ibrahim, Henri E.Z. Tonnang

All Peer-Reviewed Publications

Analysis of landmark-based morphometric measurements taken on body parts of insects have been a useful taxonomic approach alongside DNA barcoding in insect identification. Statistical analysis of morphometrics have largely been dominated by traditional methods and approaches such as principal component analysis (PCA), canonical variate analysis (CVA) and discriminant analysis (DA). However, advancement in computing power creates a paradigm shift to apply modern tools such as machine learning. Herein, we assess the predictive performance of four machine learning classifiers; K-nearest neighbor (KNN), random forest (RF), support vector machine (the linear, polynomial and radial kernel SVMs) and artificial neural network (ANNs) on …

Genetics And Immunity Of Anopheles Response To The Entomopathogenic Fungus Metarhizium Anisopliae Overlap With Immunity To Plasmodium, Tullu Bukhari, Vishukumar Aimanianda, Emmanuel Bischoff, Emma Brito-Fravallo, Karin Eiglmeier, Michelle M. Riehle, Kenneth D. Vernick, Christian Mitri

All Peer-Reviewed Publications

Entomopathogenic fungi have been explored as a potential biopesticide to counteract the insecticide resistance issue in mosquitoes. However, little is known about the possibility that genetic resistance to fungal biopesticides could evolve in mosquito populations. Here, we detected an important genetic component underlying Anopheles coluzzii survival after exposure to the entomopathogenic fungus Metarhizium anisopliae. A familiality study detected variation for survival among wild mosquito isofemale pedigrees, and genetic mapping identified two loci that significantly influence mosquito survival after fungus exposure. One locus overlaps with a previously reported locus for Anopheles susceptibility to the human malaria parasite Plasmodium falciparum. Candidate gene …

Population Ecology Of Spruce-Fir Forests Of The Interior West, Katheryn Little

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spruce-fir forest type covers nearly 10 million acres of forested land in the interior west, but there is a lack of research defining how these forests grow for future planning. Stand density index (SDI) represents the average tree size and number of trees in a stand multiplied. Each species has specific maximum number the growing space can handle known as ‘fully stocked’. If the stand is fully stocked, it must wait until trees die for individuals to grow. Spruce and fir have similar maximum stocking values, and similar growth characteristics, allowing them to be plotted together. Using current forest data, …

Avian Species Distribution Models: Using Location Data To Inform Management Decisions, Marilyn E. Wright

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Both state and federal wildlife agencies strive to conserve and protect wildlife and their habitats as an important public resource. Applied management decisions often rely on being able to obtain data that can efficiently and effectively enhance the understanding of these systems for informing management actions. Wildlife managers often focus efforts on a small subset of species from an ecosystem, typically called focal species, who can serve as surrogates for understanding the health and function of the system. Models that consider how these focal species interact with the ecosystem are often used to better understand important aspects of their life …

Extreme, Positive Geomorphic Change In A Historically Degraded Desert River: Implications For Imperiled Fishes, Tansy T. Remiszewski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rivers comprise some of the most unique and biodiverse ecosystems on the planet with their waters supporting both human societies as well as the organisms that make these rivers their home. Large rivers like the Colorado are often highly regulated and diverted in order to support human residence in arid regions like the desert Southwest, and these water diversions often have dramatic, negative impacts on the natural flow regime of the river. These impacts leave large reaches of the river dry, reduce the river’s capacity to transport sediment, cause channel and habitat homogenization, and significantly reduce the amount of suitable …

Nest‐Site Selection, Success, And Response To Predators By Cinnamon Teal And Other Ground‐Nesting Ducks In The Wetlands Of Great Salt Lake, Utah, Mark E. Bell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The wetlands of Great Salt Lake once supported hundreds of thousands of nesting ducks each year. In recent years, the number of nesting ducks in the same area was a fraction of those historic numbers. While many species of ducks do not rely on these wetlands for primary nesting habitat, cinnamon teal (Spatula cyanoptera) do. Great Salt Lake and its associated wetlands are in the heart of the cinnamon teal breeding range, and once supported half of the continental population.

These wetlands are unique from other wetlands where waterfowl nest because they are artificially created using dams to hold …

Functional Characterization Of The Newly Discovered Type V Crispr-Cas Protein Cas12a2, Dylan J. Keiser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Similarly to people, bacteria are under the treat of infection by viruses. To circumvent these threats, bacteria evolve complex immune systems. Our understanding of some of these immune systems has led to many advancements in the field of Biotechnology including tools that made expressing proteins for study in a lab easier, tools that revolutionized the feasibility of gene editing, and tools that could change the way we think about viral diagnostics and cancer therapeutics. A certain type of immune system that bacteria use to fight virus is called a CRISPR system. Presented here is work to understand the function of …

Immunological Tradeoffs And The Impacts Of Urbanization On The Reproductive Ecology And Physiology Of The Side-Blotched Lizard (Uta Stansburiana), Emily E. Virgin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investing resources into reproduction can limit energy available to other competing demands, such as fighting off an infection; yet, both processes are necessary for organisms to survive and pass on their genes to the next generation. These strategies often follow patterns associated with lifespan, such that shorter-lived animals are more likely to invest more resources into reproduction over survival, and vice versa in long-lived animals. However, environmental change caused by urbanization can disrupt these relationships, and the within- and transgenerational costs of urbanization on females and offspring are unknown. I address these uncertainties in three research chapters to better understand …

Approaches To Supplementing Silicon In Soilless Media And The Value Of Silicon In The Mitigation Of Drought Stress, Mackenzie Grace Dey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Silicon (Si) is not considered an essential element for plants to complete their lifecycle, but is known to be beneficial for plants under environmental stress such as drought. Unlike natural soils, Si is minimally bioavailable in soilless media. With indoor agriculture and greenhouse production increasing, the benefits of Si have been seen and Si should be supplemented. This work aimed to characterize and quantify the dissolution of Si from media substrates and additives to achieve a steady-state release of Si in soilless media. Typical media components such as coconut coir, peat moss, perlite, rock wool, sand, and vermiculite minimally released …

Further Evidence That Arih1 Rare Variants Predispose To Thoracic Aortic Disease, Isabella C Marin, Dianna M Milewicz

Faculty, Staff and Student Publications

No abstract provided.

Successful Creation Of Seedless (Sterile) Leucaena Germplasm Developed From Interspecific Hybridisation For Use As Forage, Daniel Real, Clinton K. Revell Dr, Yong Han, Chengdao Li, Marieclaire Castello, C. D. Bailey

Grain and Other Field Crops Research Articles

Context: The legume shrub/tree leucaena (Leucaena leucocephala (Lam.) de Wit.) is highly regarded as a cattle fodder, although it is considered an environmental weed in many parts of Australia.

Aims: We investigated the feasibility of developing a forage variety of triploid leucaena through interspecific hybridisation that is sterile (without seeds) as a strategy to mitigate its weed risk.

Methods: A conventional breeding strategy was used to create triploid hybrids from hand-crosses between tetraploid and diploid species of leucaena. Molecular markers were developed to confirm successful crosses and flow cytometry was used to confirm the ploidy level. The plants are being …

The Impacts Of A Quagga And Zebra Mussel Infestation, Casey Silva

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Invasive species issues have been on the rise in the United States for decades. These organisms can disrupt the natural flow of an ecosystem and overtake native species, altering an environment as a whole. The introduction of the zebra mussel (Dreissena polymorpha) in 1988, followed by the quagga mussel (Dreissena rostriformis) in 1989 is arguably the most prolific aquatic infestation the nation is currently up against (Hoddle, 2022). Beginning in the Great Lakes, both quagga and zebra mussels quickly spread their infestations through the Midwest and the East coast. The potential invasion of these species across …

Mitochondrial Functions Are Major Targets Of Isocyanide Activity In Saccharomyces Cerevisiae, Morgan A. Siemek

School of Biological Sciences: Dissertations, Theses, and Student Research

The isocyanide functional group is important in the synthesis of many organic compounds and is found in natural products produced by plants, bacteria, marine invertebrates, and fungi. The antimicrobial activities of isocyanide compounds have been documented for almost 70 years, however, the biochemical targets and mechanisms of action remain poorly defined. We report antimicrobial activity of 4-para-nitrophenyl-isocyanide (p-NPIC) against a model fungus, Saccharomyces cerevisiae, and the human fungal pathogen Candida albicans. To identify the cellular and molecular targets of p-NPIC, we screened the non-essential single gene-deletion collection of S. cerevisiae. We …

Environmental Determination Of Gastrointestinal Parasitism In Katahdin Sheep, Brian Arisman

Department of Animal Science: Dissertations, Theses, and Student Research

Gastrointestinal nematodes (GIN) negatively affect the performance and wellbeing of sheep and are difficult to control due to anthelmintic resistance. Producers are therefore choosing breeds naturally resistant to GIN infection, such as the Katahdin. Katahdin are raised in various climates and management systems in the U.S., and those environmental factors can be combined into eco-management clusters. We hypothesized that GIN challenge varies predictably based on the characteristics of these clusters. Katahdin producers from across the U.S. were surveyed for management information. Body weights (BW), fecal egg counts (FEC) and FAMACHA scores (FAM) were collected on 3,527 Katahdin lambs around 90 …

Nitrification Inhibitor, Nitrogen Source, And Herbicide Effects On Soil Nitrogen Transformations And Corn Yield, William Neels

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Nitrogen fertilizer management continue to be challenging due to potential nitrogen losses under variable weather conditions. The objective of this was to evaluate the performance of nitrification inhibitors, nitrogen sources and herbicides on in-season nitrogen availability and agronomy indicators. A two site-year field experiment was conducted in silty clay loam soil in corn phase of the corn-soybean rotation at Central Nebraska. The treatments included three herbicide (no pre-emergence, Acuron, Resicore) and five nitrogen treatments: 1) control, 2) anhydrous ammonia, 3) anhydrous ammonia without nitrification inhibitor, 4) urea with nitrification inhibitors, and 5) urea without nitrification inhibitors. Results indicated that nitrogen …

Deciphering The Genetic Architecture Of Key Female Floral Traits For Hybrid Wheat Seed Production, Juan David Jimenez

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Wheat (Triticum aestivum L.) is a staple cereal that provides 20% of the calories and proteins in human intake (Ray et al., 2013). Global population is projected to increase to 9.7 billion by 2050. Food production must increase by 70% to feed this future population. Wheat production is in crisis due to political and environmental challenges and is projected to decline by 0.8% in 2022 (FAO, 2022). To ensure food security yield genetic gain must increase by around 1.4% annually. Taking advantage of heterosis, hybrid wheat has the potential to boost grain yield. However, hybrid wheat seed production systems …

Quantifying The Relationship Between Soil Organic Carbon And Soil Color In Nebraska, Aldi J. Airori

Applied Science Program: Theses

Soil color is easily measured in the field and holds potential to be used as an indirect measurement of soil organic carbon (SOC). The main limitation to this approach is knowledge about the specific color-SOC relationship in a region, which often varies in relation to parent material, soil texture, climate, and land use. Furthermore, the Munsell color data is subjective in nature. The objectives of this study are: 1) to develop and evaluate the accuracy of pedotransfer functions (PTFs) for the prediction of SOC based on soil color and texture in the state of Nebraska and 2) to evaluate digital …

Remembering Clem Klaphake, Don Paseka

Nebraska Bird Review

Clement (Clem) Klaphake passed away on December 30, 2022, from complications of Parkinson’s disease, which he struggled with for several years. He was born in Melrose, Minnesota, in 1943 and grew up working on his parents’ dairy farm, which included the usual menagerie of other farm animals typical of that time. Perhaps it was the routine of milking twice a day, seven days a week, or the impressive scar on his leg from a boar tusk, but Clem was destined to leave the farm and become a life-long educator. ... After getting his degree in 1971, Clem was hired to …

Calcite Spherulite Formations And Their Controls In Halophilic Bacterial Cultures, Zakaria Jibrin

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study arose from an accidental discovery of calcite spherulites forming on colonies of various halophilic bacteria grown on solid Luria-Bertani medium made containing water from a brine pool in Death Valley, their natural habitat. Further studies with a large spherulite forming bacteria, Pseudoalteromonas haloplanktis, showed that calcite precipitation conditions were the consequence of bacteria using amino acids as a source of carbon and energy, a metabolism that produces NH3 and CO2 waste products. NH3 raises the pH of the medium, turning CO2 into CO32-. Calcium in the natural brine combines with CO32-. The resulting spherulitic calcite precipitation is nano-acicular …

A Glass Bead Semi-Hydroponic System For Intact Maize Root Exudate Analysis And Phenotyping, Martha G. Lopez-Guerrero, Peng Wang, Felicia Phares, Daniel P. Schachtman, Sophie Alvarez, Karin V. Van Dijk

Department of Agronomy and Horticulture: Faculty Publications

Background: Although there have been numerous studies describing plant growth systems for root exudate collection, a common limitation is that these systems require disruption of the plant root system to facilitate exudate collection. Here, we present a newly designed semi-hydroponic system that uses glass beads as solid support to simulate soil impedance, which combined with drip irrigation, facilitates growth of healthy maize plants, collection and analysis of root exudates, and phenotyping of the roots with minimal growth disturbance or root damage. Results: This system was used to collect root exudates from seven maize genotypes using water or 1 mM CaCl2, …

The Effect Of Volatile Organic Compounds On Endothelial Function And Atherogenesis., Samantha Mcfall

Electronic Theses and Dissertations

Volatile organic compounds (VOCs) are a group of pervasive air pollutants that are released into the atmosphere from both anthropogenic and environmental sources. Recent epidemiological studies suggest that exposure to various VOCs is associated with an increased risk of cardiovascular disease. However, the relationship between VOCs and cardiovascular disease is not well-studied. Using animal models and three select VOCs, benzene, xylene, and trichloroethylene, we studied the effects of VOCs on endothelial injury and benzene-induced atherogenesis. We found that exposure to benzene and xylene increased circulating endothelial microparticles, depleted progenitor cells, and increased platelet activation. Following the exposure to the representative …

Atlantic Surfclam (Spisula Solidissima) Population Demographics And Distribution Along The Middle Atlantic Bight, Mauricio González Díaz

OES Theses and Dissertations

The Atlantic surfclam (Spisula solidissima) is a long-lived benthic biomass dominant organism that occurs on the Middle Atlantic Bight (MAB) continental shelf between 10 m and 50 m. Trends in Atlantic surfclam population specific growth and mortality rates were analyzed using four decades of age and length observations obtained from NOAA stock surveys from the 1980s to 2010s in six regions distributed along the MAB. Atlantic surfclam specific growth rates and asymptotic lengths were estimated from the age and length observations using the von Bertalanffy growth model. The analysis showed that the Atlantic surfclam median asymptotic length in …

T-Cell Antigen Receptors In Multiple Sclerosis, Lisa Lanée Keyes Jones

Biomedical Sciences Theses & Dissertations

Multiple Sclerosis (MS) is T-cell mediated autoimmune disease characterized by inflammation, demyelination, and degeneration of axons in the brain and spinal cord. A T cell-mediated immune response in MS is directed against myelin components and possibly other antigens in genetically susceptible individuals and is triggered by a viral infection. The T-cell antigen receptor (TCR) on T cells is responsible for antigen recognition and determines specificity. Our overall hypothesis is to determine whether clonally expanded T cells in patients with MS recognize viral or self-antigens and to determine whether molecular mimicry is involved in the development of the disease. To study …

Randomization, Design And Analysis For Interdependency In Aging Research: No Person Or Mouse Is An Island, Daniella E Chusyd, Steven N Austad, Stephanie L Dickinson, Keisuke Ejima, Gary L Gadbury, Lilian Golzarri-Arroyo, Richard J Holden, Yasaman Jamshidi-Naeini, Doug Landsittel, Tapan Mehta, J Michael Oakes, Arthur H Owora, Greg Pavela, Javier Rojo, Michael W Sandel, Daniel L Smith, Colby J Vorland, Pengcheng Xun, Roger Zoh, David B Allison

Children’s Nutrition Research Center Staff Publications

Investigators traditionally use randomized designs and corresponding analysis procedures to make causal inferences about the effects of interventions, assuming independence between an individual's outcome and treatment assignment and the outcomes of other individuals in the study. Often, such independence may not hold. We provide examples of interdependency in model organism studies and human trials and group effects in aging research and then discuss methodologic issues and solutions. We group methodologic issues as they pertain to (1) single-stage individually randomized trials; (2) cluster-randomized controlled trials; (3) pseudo-cluster-randomized trials; (4) individually randomized group treatment; and (5) two-stage randomized designs. Although we present …

Characterization Of Biochar Produced From Al Ghaf Tree For Co2 Capture, Imen Ben Salem, Maisa El Gamal, Manish Sharma, Fares M. Howari, Yousef Nazzal, Cijo Xavier, Fareeda M. Almenhali

All Works

Climate change, global warming, and rise in water levels are environmental problems caused by the high emissions of greenhouse gases, and the most harmed one is carbon dioxide. Biochar is a material produced by thermochemical conversions with oxygen-depleted conditions of organic materials, and this process calls pyrolysis. Recently, it has been evaluated as a carbon dioxide capture, and its porous structure, structural properties, and production methods are easy. Al Ghaf (Prosopis cineraria) tree is one of the United Arab Emirates’ national trees with a wide range of intriguing properties, including high nutritional value, medicinal/pharmaceutical potential, and biosorption. This paper focuses …

Assessment Of Novel Protein Ingredient Arthrospira Platensis (Microalgae) And Soybean Genotype Amino Acid And Oil Selection Improvements On Broiler Performance, Savannah Wells Crafton

Graduate Theses and Dissertations

Two experiments were conducted to assess the efficiency of including novel protein ingredient Arthrospira platensis or improved soybean meal in a broiler diet. The first experiment aimed to determine the feeding value of soybean meal produced from varieties of soybeans bred for increased amino acid content (SBAA) improved oil content (SBO) compared to a conventional soybean variety in an ANOVA design fed to Cobb 500 female broilers for 28-42d of age. The SBAA and SBO soybeans contained overall higher amino acid content and lower oligosaccharide content compared to the conventional soybean variety in addition to improved oil quality. The second …

Short-Term Changes Within An Agroforestry System Managed At Three Basal Areas With Fescue Compared To Orchardgrass, Matthew Janorschke

Graduate Theses and Dissertations

Silvopasture practices incorporate forages and woody perennials in the same system in order to create a sustainable system. The main objective of this study was to determine if one of two forage species can be successfully established in order to investigate agroforestry as a management system to promote soil health. Within a bottomland mixed hardwood forest in the Arkansas River Valley, an agroforestry system was established to evaluate three basal areas (determined as the cross-sectional area of trees at breast height) (7, 11.5, and 16 m2/ha) with mounded areas and two forages, tall fescue (Lolium arundinaceum [Schreb.] Darbysh) and orchardgrass …

Cell Division Dynamics Of Escherichia Coli In Extreme Environments, Steven P. Murray

Graduate Theses and Dissertations

Life is remarkable in how resilient it can be. Many organism, classified as ex- tremophiles, can not only survive in extreme environments, but they can thrive in them. In the search for extraterrestrial life, the best candidates to harbor life exist with some kind of extreme condition. Europa, for example, is a favorite for the possibility of accommodating life as we know it within our solar system. Thought there is believed to be a liquid ocean under its icy surface, this habitat would be under immense pressures and high salinity. To best know where to look for extraterrestrial life, it …