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Identifying The Molecular Pathways That Drive Retinal Degeneration In The Childhood Neurodegenerative Disease: Mucolipidosis Type Iv, Michael Pamonag Aug 2021

Identifying The Molecular Pathways That Drive Retinal Degeneration In The Childhood Neurodegenerative Disease: Mucolipidosis Type Iv, Michael Pamonag

Masters Theses, 2020-current

Humans, like many other vertebrates, possess five Aristotelian senses (vision, olfaction, hearing, taste, and touch) which we use to experience and navigate our environment. Our visual system is the only source of light detection and light signaling in our bodies. This makes our visual system essential for detecting movement, distance, time of day, and seasonal changes in the length of days within our environment. The visual systems of most animals are designed to capture photons of visible light and convert that energy into a neurological signal (visual signal) to be transmitted to brain regions responsible for visual perception1 . This …


Is Immediate Flexibility Present In A Vocal Mimic, The Gray Catbird (Dumetella Carolinensis), Across An Urban Gradient?, Shannon K. Eppert Aug 2021

Is Immediate Flexibility Present In A Vocal Mimic, The Gray Catbird (Dumetella Carolinensis), Across An Urban Gradient?, Shannon K. Eppert

Masters Theses, 2020-current

Increasing urbanization has increased anthropogenic noise levels near developed areas. Urban noise is high amplitude and low-frequency, and these frequencies can overlap with the signals animals use to communicate, including bird songs. Many urban birds sing higher minimum frequencies in urban areas, which avoids some masking by noise, but the mechanism behind this difference is not well understood. Immediate flexibility is the ability to alter song in real-time in the presence of sudden noise, allowing for avoidance of masking and better signal transmission. I investigated if male catbirds increased signal transmission in the presence of anthropogenic versus high-frequency noise playback …


A Stable-Isotope Probing Approach To Modeling Bidirectional Nutrient Exchange In The Microcystis Phycosphere, Malia Gardner Aug 2021

A Stable-Isotope Probing Approach To Modeling Bidirectional Nutrient Exchange In The Microcystis Phycosphere, Malia Gardner

Masters Theses, 2020-current

Cyanobacterial harmful algal blooms (cHABs) plague freshwater systems worldwide and are projected to increase in intensity in the coming decades. cHABs damage aquatic ecosystems by blocking light penetration into the water column, creating hypoxic conditions, and releasing toxins. One of the most prolific cHAB formers is the cosmopolitan genus of cyanobacteria Microcystis. Global climate change and anthropogenic loading of nutrients such as nitrogen (N) and phosphorus (P) fuel Microcystis bloom formation. Increasing global temperatures favor Microcystis because of its high optimal growth temperature. N input is of particular importance for Microcystis because it is unable to fix atmospheric N, …


Ecophysiology Of Toxic Bloom-Forming Cyanobacteria And Their Symbionts, Dominique J. Lockwood Aug 2021

Ecophysiology Of Toxic Bloom-Forming Cyanobacteria And Their Symbionts, Dominique J. Lockwood

Masters Theses, 2020-current

Currently, there is a pernicious microbe in the genus Microcystis that is putting the world’s freshwater resources at risk. A member of the phylum Cyanobacteria, otherwise referred to as blue-green algae, Microcystis forms massive algal blooms in lakes and has the potential to produce a toxin, which does not only harm humans, but also pets, livestock, and aquatic life. As recently as 2016, in the city of Toledo, Ohio, nearly 1 million residents went without clean drinking water for an entire weekend due to one of these Microcystis blooms. However, Microcystis does not only bloom in Ohio. In fact, …


Population Study Of Native And Invasive Turtles In Harrisonburg, Virginia, David R. Weisenbeck May 2021

Population Study Of Native And Invasive Turtles In Harrisonburg, Virginia, David R. Weisenbeck

Senior Honors Projects, 2020-current

The Red-eared Slider, Trachemys scripta is an invasive species responsible for declines in turtle species across the world. Trachemys scripta is native to two parts of southern Virginia but the species has been introduced throughout the rest of the state, often related to the release of pet trade animals. This study aimed to identify the extent of Trachemys scripta’s establishment and impact on native species in Harrisonburg, Virginia. Turtles were trapped in a mark-recapture study during the springs and summers of 2018, 2019, and 2020 in four local ponds in Harrisonburg, Virginia. Cormack-Jolly-Seber population models were constructed using data …


Postprandial Exhaled Nitric Oxide Responses In Older And Younger Adults With And Without Acute Exercise, Molly Miller May 2021

Postprandial Exhaled Nitric Oxide Responses In Older And Younger Adults With And Without Acute Exercise, Molly Miller

Masters Theses, 2020-current

A single high fat meal (HFM) increases airway inflammation in young, healthy individuals. Additionally, aging increases airway resistance and inflammation, though the airway inflammatory response to a HFM has not been investigated. Exercise is a natural anti-inflammatory, but has yet to be administered with a HFM as a method to study postprandial airway inflammation in older adults. Purpose: To investigate whether older individuals have greater postprandial airway inflammation compared to younger counterparts, and to explore whether exercise may modify the postprandial airway response in older adults. Methods: 12 younger adults (23.3±3.9 years; 5 M/7 F) and 12 older adults (67.7±6 …


Comparing The Effect Of Four Propagation Techniques On Hybrid Chestnut Seedling Quality, Taylor Evans May 2021

Comparing The Effect Of Four Propagation Techniques On Hybrid Chestnut Seedling Quality, Taylor Evans

Masters Theses, 2020-current

Extensive resources have been used to breed hybrid chestnuts for reintroduction into the historical range of the American chestnut (Castanea dentata). Improving seedling quality is an efficacious method to improving restoration outcomes and nursery propagation methods can be selected to improve seedling quality, increasing the likelihood of survival. Four production methods (bed grown, air prune beds, container grown, and the Root Production Method®) and three media types (field soil, peat-perlite-vermiculite mix, and pine bark-rice hulls-sand mix) were compared across four measures of seedling quality (height, root collar diameter, root volume, and number of first order lateral roots) to …


Plant-Pollinator Network Dynamics Of The Little Fork Shale Barren, Sarah N. Brown May 2021

Plant-Pollinator Network Dynamics Of The Little Fork Shale Barren, Sarah N. Brown

Masters Theses, 2020-current

Shale barrens are steep sloping mountainside ecosystems characterized by rocky Upper Devonian age shale substrate, high light, and low water availability. They form an array of biogeographical “islands” throughout Mid-Appalachia whose niche dynamics, response to disturbance, and pollination ecology remain to be investigated. Using network analysis, this project addresses three objectives to fill gaps in shale barren pollination ecology. (i) Compare vegetative species composition, richness, diversity, and evenness to a descriptive vegetation study completed at the same site 27 years prior. ii) Outline the topology of plant-pollinator networks including identifying phenologically accurate networks, the architecture of such networks, and identifying …