1st Place and People's Choice winner
|Identifying Soil Microbial Transformations as Drivers of Nitrous Oxide Loss from Agroecosystems
Agricultural systems need to use nitrogen (N) fertilizers to increase crop yield to meet dietary needs of the growing human population. This results in excess N loading into soils and increases soil microbial activity. Enhanced microbial processing of available N leads to N pollution in the atmosphere and water systems. Nitrous oxide (N2O), an extremely potent greenhouse gas, is released during these biological processes, but the mechanisms responsible for N2O release are not fully understood. I propose the utilization of naturally occurring stable isotopes to determine the real-time biological origin of soil emitted N2O. This approach will make it possible to determine how environmental factors, such as soil temperature and moisture, drive biological communities responsible for N2O loss. This work is imperative if we wish to implement agricultural management practices that will decrease gaseous N loss without affecting crop yield. The global population is continuing to increase, and food production needs to increase by more than 50% by 2050 to sustain predicted population sizes. Nitrogen fertilizer application will also need to increase to meet growing dietary demands, and this will increase harmful N2O emissions. Identifying the biological communities responsible for N2O loss will allow for implementation of management practices to protect human and environmental health.
Mathematics and Statistics
|Mathematical Modeling of Contaminant Transport in River/Stream
Over the years, river water pollution by various contaminants from human activities has been posing a major threat to the freshwater resources all over the world. The leapfrog scheme is a finite difference scheme and widely used numerical method to solve a mathematical model. It is a scheme which produces artificial dispersion to an extent even when the stability condition is met. The objective of this paper is to investigate the dispersive behavior due to the leapfrog scheme, and we focus our attention to deriving a scheme that eliminates dispersion brought by implementing the leapfrog scheme. To demonstrate the presence of the dispersion and to study it in brief, we used a one-dimensional advection transport equation that governs the transport phenomena.
Mathematics and Statistics
|Age Based Enclosed Space Covid-19 Model
To research an enclosed space droplet/aerosol disease spread model when it is adapted to take into account an age based mixing model. Overall we would like to explore what kind of effects inter-age mingling in ventilated spaces has on disease propagation, specifically in the case of Covid-19.
|Assessing Nitrogen Deposition in Mountainous Regions: Nitrogen Critical Loads in the North Cascades
Human activity has significantly altered the nitrogen (N) cycle. Transportation, industry, and agriculture all emit reactive N into the atmosphere, which can then be transported and deposited back onto terrestrial and aquatic ecosystems as atmospheric N deposition (Ndep). Anthropogenic Ndep contributes globally to disruptions in nutrient cycling, ecosystem functioning, and shifts in community composition. National Park Service (NPS) lands, including the North Cascades National Park Service Complex (NOCA), contain ecosystems that are potentially sensitive to Ndep. Accurate measurements of Ndep are needed to determine N critical loads, levels of Ndep that can be sustained without adverse biological effects. However, model estimates have a high degree of uncertainty, especially in mountainous regions such as the North Cascades. The N concentration of epiphytic lichens can be utilized to monitor Ndep because the relationship between lichen N concentration and Ndep can be determined for a given region, and their N stable isotope composition (15N) can assess contributions of different N emission chemistries. Lichen communities, comprised of species with varying tolerances to N, can be assessed as an indicator of levels of Ndep as well. The goal of this study is to determine which ecosystems in the North Cascades are affected by Ndep and identify predominant sources of N emissions. N critical loads can be used by air regulators to develop strategies and policies to reduce N emissions. This will eventually result in the long-term health of ecosystems on federal lands for the benefit of future generations.
|Material Bodies and Textual Selves: Reimagining Gender and Sexuality in the Twenty-First Century
My dissertation focuses on contemporary sex-positive, trans, and queer writers Virginie Despentes, Paul B. Preciado, Maggie Nelson, and Michelle Tea and their respective genre-bending autotheory/autofiction works: King Kong Theory (2010), Testo Junkie (2013), The Argonauts (2015), and Black Wave (2016). I position these texts as products of a French/Francophone-American feminist and queer theoretical exchange, particularly in the ways in which American theorists and sex-positive writers and activists of the 1990s, such as Judith Butler and Annie Sprinkle, informed French feminist and queer scholars, such as Sam Bourcier and Preciado, who created a queer/postpornographic feminism that generates new conceptions of queer feminist subjectivity in the twenty-first century. Contextualizing these texts as products of a transatlantic relationship, I examine how these narratives are informed by our neoliberal, late capitalist era that, according to Rosi Braidotti and Chandra Talpade Mohanty, encourages the production of identities to commodify them. Drawing from the scholarship of Bourcier, Dean Spade, Cathy Cohen, and Lisa Duggan, I highlight that this commodification works within a homonormative, neoliberal framework to depoliticize queer and feminist movements in the United States and France.
However, these authors, I argue, underscore the way their identities shift alongside their bodily materiality (through sex, hormone administration, pregnancy, narcotic and alcohol use, and sobriety) to emphasize how their subjectivities are understood as material-discursive phenomena that resist easy categorization and center possibility. Portraying their selves as subject/objects in their autotheoretical and autofictional works, they use their bodies as sites of political imagination that can counter the normalizing impulses of the twenty-first century and resist the commodifying systems that disempower radical feminist and queer movements.
Although I overall conclude that these texts offer generative conceptions of identity to challenge oppressive heteropatriarchal systems, I do also account for the way these narratives could further interrogate race and whiteness to form a more expansive queer politics. This is particularly important in the far-right turn of the last decade, which has seen increasing attacks on women, people of color, and LGBTQIA+ communities.