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The importance of fluvial geomorphology and watershed restoration for the New Mexico jumping mouse
No full textThe New Mexico jumping mouse (Zapus luteus luteus, formerly New Mexico meadow jumping mouse, Zapus hudsonius luteus) is a federally endangered small mammal that persists in isolated populations in Arizona, New Mexico, and Colorado. This riparian obligate requires dense, structurally diverse riparian vegetation and perennial flowing water. Alterations to the natural fluvial conditions of a watershed can directly affect the quality of riparian habitat available. Stream geomorphic data is used to describe the condition of fluvial processes, riparian habitat, and floodplain creation and maintenance. The purpose of this study was to determine the effects of local fluvial geomorphology on use of streams by the New Mexico jumping mouse in the southwest United States. In 2020, we collected geomorphic data from 58 stream reaches in montane meadows and forests in the White Mountains of eastern Arizona. Stream reaches that supported the presence of jumping mice (n = 31), compared to those that did not (n = 27), had a greater median bed material size (D50), greater sinuosity, lower bank-height ratio, channel evolution stage I, IV, or V, lower width-depth ratio and slope, and a greater width flood prone area, meander-width ratio, and entrenchment ratio. D50, sinuosity, and bank-height ratio were strong predictors of presence. Channel evolution stage, width flood prone area, and entrenchment ratio were of moderate predictive importance. Width-depth ratio, stream type, meander-width ratio, and slope were weak predictors. As bank-height ratio increased, the probability of presence of jumping mice at a site decreased. In contrast, as median bed material size and sinuosity increased, the likelihood of use by jumping mice increased. Streams that are actively degrading due to bank erosion can exhibit an increasing bank-height ratio and may also see a decrease in sinuosity and bed particle size (D50) over time. Channel incision can contribute to a drop in the water table, disconnection of the channel from the historic floodplain, and shift the plant community from riparian to upland associated species. Riparian areas are an important resource, especially in the arid Southwest. Changes in habitat management should incorporate watershed restoration actions that improve long-term channel stability, eliminate sources of degradation, and support geomorphic and hydrologic conditions that are foundational to the creation and maintenance of riparian habitat
A picture is worth one thousand words: introduction of the Sexual Harassment Inventory of Photographic Stimuli
No full textIn the wake of the #MeToo movement, sexual harassment has been brought to the forefront of the minds of the American populace. Ambivalent Sexism Theory describes the interaction between two types of sexism, Benevolent Sexism and Hostile Sexism, which facilitates the continuation of sexist sentiments within our society. Research suggests, however, that individual perception plays a large role in whether a person labels an act as sexually harassing. Historically, methods for assessing perceptual data on sexual harassment has relied on verbal interviews or written surveys, which can be limiting in the breadth of populations in which researchers can utilize these tools. The popularity of pictorial stimulus measures has revealed the versatility of utilizing pictures to gather data from a variety of individuals and in diverse settings. The current study seeks to validate a novel pictorial stimulus package (the Sexual Harassment Inventory of Pictorial Stimulus; SHIPS) for use in sexual harassment perception research
Self-Propelled Motion of TiO2 Micron Sized Helical Particles
No full textActive matter micro-particles have been observed to utilize energy to overcome Brownian motion and propel themselves. Micron to nanometer sized active matter particles have become of interest due to their potential applications ranging from drug delivery, pollutant removal, simulating biological systems and exploring emergent behaviors. Learning how to control the movement of these tiny particles is a step in understanding the phenomena of active matter particles. This thesis is concerned with controlling particle motion by empirically studying how particle chirality and material interfaces affect the motion of micron sized titanium dioxide semiconductor particles. Particle chirality is achieved through a helical tail which is grown in a physical vapor deposition system. When in a hydrogen peroxide solution and exposed to ultraviolet light, these particles will catalyze the decomposition of hydrogen peroxide and consequently cause the particles to \enquote{swim} in solution. A light microscope is used to record image sequences of these particles in action. These sequences are then processed and analyzed. Particle characterization was accomplished using a scanning electron microscope and elemental mapping was achieved through energy-dispersive x-ray spectroscopy. Results show that the chiral particles swim in circles but prefer to swim in opposite directions (clockwise or counterclockwise) with the preferred direction dependent on the particle's chirality. A difference in overall speed was also seen between the two chiralities. It was shown that a semiconductor-metallic interface changed particle speed and can change the direction in which the particles swam
Deep Learning based digital hologram processing
No full textDigital holography imaging utilizes the special properties of light and photons to capture the detailed images of microscopic objects, such as organs, tissues, and cells. Usually, phase information is used to reconstruct the surface of the target objects. Digital in-line holography is a widely used phase imaging method due to its simplicity of experimental setups. However, reconstructing the phase and amplitude planes from the raw holograms is hindered by couples of problems, such as the twin image problem due to the diffusion pattern and the noise caused by the environmental factors. Therefore, different analytical and numerical methods were proposed to tackle these problems. Recently, Deep Learning (DL) has been deployed in a range of computer vision tasks that achieve better performance than traditional machine learning methods. This thesis demonstrates the usage of DL methods to address hologram reconstruction and phase and amplitude image denoising. This thesis is formed in two aspects: (1) In Chapter 1, a deep learning based hologram reconstruction method was proposed that can reconstruct the phase and amplitude image from a single shot hologram without massive training data. We train a convolutional autoencoder with a physics-driven loss function that can produce twin image-free results from the captured hologram. We compared the proposed method with the state-of-art compressive sensing method on simulated data. We also compared the proposed method with the multi-height Transport of Intensity Equation (TIE) based algorithm on real-world optical experiments. Experimental results show that the proposed method could produce better results than single shot compressive sensing method and achieve comparable results to the multi-height TIE based algorithm. (2) Chapter 2 aims to boost the performance of Channel attention model for image denoising tasks. We proposed to use Discrete Wavelet Transform to decompose the feature maps into different frequency subbands and deploy the channel attention to these subbands. We evaluate the proposed methods on both natural image denoising and phase and amplitude image denoising. The results show that the proposed method achieves an outstanding performance for various noise and data types
Mapping virus-associated health disparities utilizing highly-multiplexed serology
Get PDFDespite advancements in medical interventions, disease burdens caused by viral pathogens remain large and highly diverse. This burden includes the wide range of signs and symptoms associated with active viral replication as well as a wide range of clinical sequelae of infection. Viral infections have even been linked to the onset of a number of non-communicable diseases such as diabetes, celiac disease, and Alzheimer's disease. Although these diseases are of a global burden, currently documented national trends highlight several gender and ethnicity-based health disparities associated with viral infections and thus, viral-associated disease. Despite these well documented disparities in viral infection rates, our understanding of virus-associated health disparities remains incomplete. In part, this is because the most commonly used viral detection methodologies lack the sensitivity and specificity for broad characterization of viral exposures. Here we utilize PepSeq technology to develop a sensitive, high-throughput assay for characterizing an individual’s nearly complete history of viral exposures within a single reaction. Here, we demonstrate the effectiveness of this approach for broadly detecting virus-associated health disparities through a pilot study in Phoenix, AZ. Using PepSeq, we recapitulated known seroprevalence rates for many common viruses and identified both expected and unexpected infection rate disparities between a Hispanic white (HW) and non-Hispanic white (NHW) populations
First-generation and Pell Grant-eligible, navigating the financial aid verification process: a case study
No full textSeeking admission to post-secondary education can pose a challenging landscape for first-generation college students (FGCSs) (Chen & Carrol, 2005; Engle, 2007; London, 1989, 1996; Padgett et al., 2012). One of the most significant challenges this student group faces is navigating finances and paying for college (Bennett et al., 2015; Dumais & Ward, 2010; Engle, 2007; London, 1989, 1996; Padgett et al., 2012; Rubio et al., 2017). Many FGCSs are from low-income families (Higher Education Opportunity Act, 2008), placing them in the Pell Grant-eligible range for federal financial aid (Federal Student Aid, n.d.b). Pell Grants are awarded to students from low-socioeconomic status with the most financial need of any college-going student (Federal Student Aid, n.d.b). Data indicates that half of Pell Grant-eligible students are selected to complete the financial aid verification process after the student fills out and submits their Free Application for Federal Student Aid (FAFSA) (Warick, 2018). The 50% selection rate for Pell-eligible students is nearly three times higher than the national average selection rate for the 2020-2021 academic year, which sits at 18% (Hoover, 2020). The verification process requires additional documentation to be submitted by the student or student’s family to the institution of higher education to verify the accuracy of what was listed on the FAFSA, a step that causes additional delays and potential problems for incoming applicants. Additionally, the verification process has been identified as a significant hurdle selected students must overcome to receive the financial aid needed for attendance (Kreighbaum, 2019; Smith, 2018a; Wiederspan, 2019). This study assessed how FGCSs, who were Pell Grant-eligible and selected to complete financial aid verification, successfully navigated the verification process during their transition to a university. This study is a qualitative case study, and the researcher interviewed fourteen participants through videoconferencing. This study utilized Nancy Schlossberg’s (1981) transition theory and the factors of adaptation during a transition as the conceptual framework to build the research questions, interview questions, and guide how the data were analyzed to understand what factors contributed to the participants navigating the verification process successfully. All fourteen participants were FGCS, Pell Grant-eligible, and had been selected to complete the financial aid verification process during their initial college-going progression to a university in the southwest United States.
Results from this study showed that the financial aid verification process posed a significant barrier for some students. It can be a stressful experience in a litany of already confusing steps for a student population unfamiliar with the college-going process. Low-socioeconomic FGCSs do not have the social capital, economic resources, or familial support their generational counterparts have when enrolling in a university. The addition of this particularly significant barrier to admission can be a deterrent to their enrollment. This study also outlines the factors of adaptation from Schlossberg’s (1981) transition theory the participants utilized to navigate the verification process and receive their needed financial aid. It also focuses on how this federally mandated process targets lower socioeconomic students by having them prove their financial and societal status through the verification process.
Keywords: first-generation college students, Pell Grant-eligible, financial aid verification, factors of adaptation, transition theor
Large mammals and the zoogeochemistry of terrestrial nutrient cycles
Get PDFStudies from across the world demonstrate that nutrient resource subsidies by animals critically shape ecosystem composition and function. In particular, large mammals have been found to act as the planet’s nutrient arteries, connecting and fertilising landscapes through which they pass. However, a comprehensive understanding of the cumulative impacts of lateral nutrient transport by diverse clades of mammal taxa remains lacking. This dissertation develops quantitative frameworks from which to better attribute and estimate the magnitude of nutrient redistribution by large mammals. First, I apply machine-learning techniques to improve the prediction of key animal traits (gut retention time) and nutrient biogeography (sodium). I then develop an agent-based model that incorporates individual-level decision making for quantifying the transport of nutrients across a nutrient discontinuity in the Amazon basin. Collectively, these studies improve our understanding of biotic nutrient dispersal and provide a framework that can be applied to diverse terrestrial ecosystems across the world. My final two chapters assess how wildlife managers can incorporate nutrient redistribution by large mammals into management plans, whereby holistic strategies promote the long-term fertility of landscapes. Over the last 50,000 years, numerous large mammal species have been extirpated from ecosystems across the world. Today, the global south shoulders much of the burden for preserving large mammal species. This dissertation provides a biogeochemical rationale for the growing movement of rewilding, which aims – in part – to rebalance the geographical responsibility for large animal conservation
Analysis and Comparison of Travel Times Using Multiple Data Sources: A Case Study in Metro Phoenix
No full textTravel time on the arterials and corridors has been one of the critical topics of the agencies and DOTs. There are many ways to collect the data, and each has its advantages and challenges. Loop detectors, camera detections, Wi-Fi, and Bluetooth signals are some of the few ways used in this regard, which different companies provide. This thesis compares the travel time calculated using Inrix and Acyclica data for the W Cactus road from 75th Avenue (Ave) to 91st Avenue, Peoria, AZ, and the roads reaching its intersections. The analysis was done in two scenarios and three times of the day. Scenario A is the existing condition in which the traffic signals are running free (actuated) with dynamic max. Scenario B is when the traffic signals are coordinated along the Cactus road in both directions. Inrix has multiple sources to collect and analyze data to provide the results to its users. Acyclica uses the unique Wi-Fi signature of the passing vehicles and compares the recorded time stamps to calculate travel time and speed and other travel data. Using the data collected by each source, the travel time was calculated for each time of day and compared with the results provided by the other source using a t-test at a 95% confidence level. It was concluded that in most cases, Inrix and Acylica are reporting different results, especially for the main road. Next, the travel time at each scenario and time of day provided by each source was compared to determine whether the difference between the two sources stays the same while transitioning from scenario A to B. It was needed to know if the change in traffic service conditions can affect how these two sources are reporting their data. It was found out that the difference between Inrix and Acylica changes mainly in the main street. The thesis then explores possible reasons behind this by studying the data recorded by each source and the behavior of the travel time distributions and cumulative distribution function plots
Identifying the Use of Culturally Responsive Teaching Strategies in Out of School Time STEM Classsrooms
Get PDFThis study sought to understand how culturally responsive teaching strategies occur in out-of-school time settings and how a high-quality STEM curriculum may influence these strategies. Two educators with unique backgrounds were observed in two different out-of-school time (OST) programs in the U.S. Because of their unique backgrounds, their use of culturally responsive teaching strategies manifested themselves differently among the two programs. Using a previously developed, high-quality STEM curriculum, we were able to classify and interpret how they were implementing cultural relevance in their classrooms and understand the impact of the curriculum. Observations, interviews, and implementation logs were coded and analyzed through quantitative and qualitative means. While this study was part of a more extensive study funded by NASA to develop middle school STEM OST curriculum, we were able to find some unique results. We discovered that OST educators might significantly differ in how they enact culturally responsive teaching practices in an OST classroom, perhaps because of their teaching background and experiences. Another result indicates that because OST educators come from various teaching experiences, a curriculum that could implement culturally responsive teaching (CRT) strategies may allow educators to connect with their youths in more profound, more meaningful ways. Because OST programs across the country hold different youth goals, teaching moves that encourage cultural relevance could be a robust strategy that allows the OST program to enrich youth experience
D E L I V E R Y (Delivery)
Get PDFD E L I V E RY is a novella about a futuristic world that essentially works fine, and a woman forced to find out why. The story is set in a Pacific nation, the Sol Coast Republic, in a future so distant that the United States is an embarrassing memory, but with technology that is only slightly more advanced than we see around us today. We, humanity, have achieved universal peace and plenty, and yet Ciara Way, the protagonist, still chooses to have an actual job. She is a courier, and she hand-delivers packages to reclusive clients throughout the southwest, and one day finds herself caught in a conspiracy of self-driving cars, wiry robotic monsters, and intelligent racoons.
This novella has a long developmental history. Its earliest seed was planted in a few writing exercises in Erin Stalcup’s undergraduate fiction workshop. One piece was a hybrid poem/story/computer code about a woman in a lilac dress executing a robot, the other scraps of an outline about an eccentric woman training pet racoons to unlace shoes. The hybrid piece was submitted in my application packet for MFA programs, which I hope helped convince the NAU program to accept me into theirs. Almost two years later, in the Spring of 2020, I revisited the concepts in a hasty draft for Dr. Nicole Walker’s environmental writing class, and then expanded that into the first few chapters in Chelsey Johnson’s fiction workshop, where I hoped to restructure the narrative into something that contorts the classic hero’s journey into a more woven, wavey series of events that do not necessarily leave the reader with answers, but instead lay out clues that invite them to practice the hard work of resolution in the face of calamity themselves.
I have been feeling the burden of the impending apocalypse, in both life and in literature, and wanted to write a story from the perspective of a world that overcame it. The principle writing of the piece straddles the consequential divide from before and after the COVID-19 pandemic began, and while not directly speaking to that national shame and global tragedy, I hope the work imparts the precarity of humanity, and the struggles we face to maintain our balance between peace and justice. When I set my story in a utopian future, my intent was not to allow myself to simply worldbuild away a global reckoning with the injustice spurred by centuries of colonial violence, or to plaster over the imminent struggle of climate change. Instead, I hoped to present an audience with a lens with which to see another world where those wounds have become scars, and the turmoil that comes from both their prolonged existence, and hopefully one day, sincere attempts at healing.
My reaction to contemporary climate science fiction and the classics of u/dystopian literature informs the character, plot, and themes of D E L I V E R Y. The long time of history explored in works like the Foundation series by Isaac Asimov (introduced to me by Dr. Karen Renner), and more recently in N. K. Jemisen’s The Broken Earth series, informs my dissection/creation of the competing cultures that vie for philosophical dominance in the Sol Coast. In my interrogation of the tool of violence that pervades the cyberpunk future in works like Neuromancer by William Gibson, and is still ongoing in popular cli-fi works like Octavia Butler’s Parable of the Sower and Paolo Bacigalupi’s The Water Knife, I hoped to present a more straight-faced ideological struggle for my human characters to overcome. Two more works, whose inspiration speaks to the value of the NAU M.F.A programs commitment to cross genre and hybrid exploration, is Anna Tsing’s The Mushroom at the End of the World and Elizabeth Kolbert’s The Sixth Extinction, both of which gave me a non-fiction grounding for the complexity of the ecological and social narratives that shape our world on which to base my elaborate science fiction machinations.
As much as I love my worlds within worlds, the setting and character work that demands the sentences of prose fiction, I could not help but sprinkle my other passion for words within words, as fostered especially by Nicole Walker’s poetry workshops. I hope that my fanciful phrases and etymological symbologies do not distract but enhance the contemplative tone of the novella. I also was heavily inspired by the aesthetics of the Vaporwave digital music genre as a foil to the industrial, orientalist roots of the cyberpunk genre D E L I V E R Y hopes to contend with, and by my life growing up in desert of the Phoenix, Arizona valley, desperately hoping to escape the heat.
My peers in my MFA program, as well as my professors, including those not yet mentioned above, Sherwin Bistui, Lawrence Lenhart, and KT Thompson, have been an invaluable source of inspiration for not just D E L I V E R Y, but all of my recent writing. Special thanks to Dr. Ann Cummins, who taught my very first fiction workshop in the Spring of 2014, and tricked me into doing this writing thing when she praised my story about a kid stuck in a Jeep with their smoking dad, driving off-road through the Arizona desert, and finding an old, rusted shack