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Effects Of Commercial Formulations Of Glyphosate On Saccharomyces Cerevisiae, Apoorva Ravi Shankar

Graduate Theses, Dissertations, and Problem Reports

Commercial formulations of glyphosate are among the most extensively used herbicides around the world. The active ingredient, glyphosate, targets the aromatic amino acid pathway. This pathway is absent in mammals, resulting in low toxicity. Different formulations contain varying adjuvants and surfactants, whose synergistic effects are yet to be extensively studied at the cellular level. In this study, I tested multiple commercial formulations that showed a variation in growth phenotype among different yeast strains. To gain a better understanding of response and resistance mechanisms at the genome and transcriptome level, I carried out an in-lab evolution study, along with a transcriptome …

Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen

Graduate Theses, Dissertations, and Problem Reports

Amphibians are facing global declines due to climate change, loss and degradation of habitat, invasive species, and disease. The Appalachian region of the eastern USA is a global biodiversity hotspot for salamanders, which are considered keystone species that influence nutrient dynamics in terrestrial and aquatic food webs. There are high rates of salamander endemism in the Appalachian region, with many species restricted to isolated, high elevation areas. The Cow Knob Salamander (Plethodon punctatus) is one such species. It is only found at elevations >675 m (most populations are above 900 m) on Shenandoah Mountain, North Mountain, and Nathaniel …

Compound-Specific Isotope Analysis Of Amino Acids In Biological Tissues: Applications In Forensic Entomology, Food Authentication And Soft-Biometrics In Humans, Mayara Patricia Viana De Matos

Graduate Theses, Dissertations, and Problem Reports

In this work we demonstrate the power of compound-specific isotope analysis (CSIA) to analyze proteinaceous biological materials in three distinct forensic applications, including: 1) linking necrophagous blow flies in different life stages to their primary carrion diet; 2) identifying the harvesting area of oysters for food authentication purposes; and 3) the ability to predict biometric traits about humans from their hair.

In the first application, we measured the amino-acid-level fractionation that occurs at each major life stage of Calliphora vicina (Robineau-Desvoidy) (Diptera: Calliphoridae) blow flies. Adult blow flies oviposited on raw pork muscle, beef muscle, or chicken liver. Larvae, pupae …

Comparing The Effects Of Swimming Exercise And Dissolved Oxygen On Important Performance Parameters Of Early-Rearing Atlantic Salmon Salmo Salar And Rainbow Trout Oncorhynchus Mykiss., Thomas B. Waldrop

Graduate Theses, Dissertations, and Problem Reports

Swimming exercise (bodylenghts/sec), and dissolved oxygen (DO), are important environmental variables in aquaculture. While there is an obvious physiological association between these two parameters, their interaction has not been adequately studied in Atlantic salmon, Salmo salar and Rainbow trout, Oncorhynchus mykiss. Since both variables can be easily manipulated in modern aquaculture systems, we sought to assess the impact of these parameters, alone and in combination, on the performance, health, and welfare parameters of the two species. Atlantic salmon and Rainbow trout were stocked into twelve circular 0.5 m³ tanks and exposed to either high (1.5-2 BL/s) or low …

Sodium Channel Distribution In The Apical Dendrites Of Pyramidal Cells Vary In The Hindbrain Of Apteronotus Leptorhynchus., Sree Indrani Motipally

Graduate Theses, Dissertations, and Problem Reports

Apteronotid weakly electric fish heavily rely on their electrosensory system for behaviors like spatial navigation, communication and prey capture. Since the behaviorally important information about their environment is contained in the spatial and temporal modulations of the electrosensory signal, efficient mechanisms to process this information with great fidelity are of the utmost importance. Efficient sensory processing often involves having multiple parallel processing streams so that each stream can specialize to treat signals with different properties. This strategy requires the response properties and neural dynamic to be adjusted in each pathway to implement different neural coding strategies. One of the neural …

The Effects Hot Water Kill Time Has On Dna Degradation And Str Profiling From Lucilia Sericata (Diptera: Calliphoridae) Crop Contents, Nicholas Alexander Haas

Graduate Theses, Dissertations, and Problem Reports

he use of entomological specimens as a source of forensic DNA evidence has been studied since the late 20th century. Currently as it stands, to preserve both the minimum postmortem interval (mPMI) and DNA evidence within fly larvae, two standards of preservation exist. For mPMI, the use of hot water kill with near-boiling water is used to fix larvae size for accurate age estimation. For DNA evidence, the standard technique of preservation is submersion in 70% ethanol. To help reduce the number of standard preservation techniques for practitioners, this study assessed the feasibility of the hot water kill preservation technique …

Population Health Of Spotted Salamanders (Ambystoma Maculatum) In Created Vernal Pools: An Integrative Approach, Alice R. Millikin

Graduate Theses, Dissertations, and Problem Reports

Habitat creation is an important tool for conservation to counteract habitat loss and degradation. Vernal pools are susceptible to destruction due to limited detection, protection, and regulation. These wetlands provide fishless breeding habitat for many amphibian species including spotted salamanders (Ambystoma maculatum) in eastern North America. Determining whether created vernal pool habitat is successful is often determined by demographic data of colonizing populations. I suggest that hormone levels, population genetics, and disease prevalence can improve our understanding of population health in created habitat. The goal of this dissertation was to assess the health of spotted salamander larvae in …

Canonical Wnt Mechanisms In Neural Crest Induction, Mark Stephen Perfetto

Graduate Theses, Dissertations, and Problem Reports

Canonical Wnt signaling is a pathway that is critical for normal development and the progression of disease. The canonical Wnt signaling pathway was put together carefully by synthesizing decades of research. Over those decades, canonical Wnt signaling was found to be crucial for nearly all aspects of development, but of importance to this thesis, is a key regulatory factor for the development of the highly migratory multipotent stem cells, the neural crest. As our knowledge of the importance of canonical Wnt signaling grew, research is being conducted to further our understanding of how canonical Wnt signaling communicates with other signaling …

Analysis Of User Preference With N95 And Powered Air-Purifying Respirators In A Healthcare Work Environment, Brittany Renee Carver

Graduate Theses, Dissertations, and Problem Reports

For those working in the healthcare field, personal protective equipment is vital. Healthcare workers are often first responders when it comes to dealing with patients who are infected or when a disease outbreak occurs. The Occupational Safety and Health Administration (OSHA) requires all healthcare operations to provide employee protection against blood borne pathogens. With the increase of life-threatening disease outbreaks, such as SARS in 2003 and Ebola in 2014, it is of the upmost importance to make sure respirators are best suited for users and acceptable for long term use. It has been shown through previous studies that due to …