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Characterization of a Tunable All-Reflective Spatial Heterodyne Spectrometer
No full textWe present the characterization of a prototype Tunable All-Reflective Spatial Heterodyne Spectrometer (TARSHS), a novel extension of the already-existing and successfully flight-demonstrated All-Reflective Spatial Heterodyne Spectrometer (ARSHS) design. ARSHS is recognized for its high resolving power (R > 105), wide field of view (FOV), and unique optical design that is especially well-suited for UV-visible remote sensing of faint and extended planetary and astrophysical targets. However, ARSHS utility is limited by a fixed and narrow bandpass. TARSHS overcomes this limitation by incorporating motor-driven rotation stages into the instrument pilot mirrors, enabling rapid selection between many different bandpass centers across a broad spectral range. This tunability significantly enhances the instrument’s versatility and potential science return per flight without sacrificing the high R and FOV that are characteristic of base ARSHS design. The TARSHS prototype reported below, assembled primarily with commercial-grade components, demonstrated a resolving power of R = 30,000 across an operable range of 400 – 700 nm. Stable, reliable tuning and minimal degradation across its tunable range were found, supporting its readiness for higher technology readiness levels (TRL). This study outlines the optical configuration, operational mechanics, and prototype results, establishing TARSHS as a robust, cost-effective tool for space-based spectroscopy. Future efforts should focus on miniaturization and environmental validation for deployment on robotic missions
Liquid Biopsy Detection of Aberrant DNA Methylation as a Biomarker for Monitoring Reoccurrence in Trodelvy-Treated Triple-Negative Breast Cancer Patients
Get PDFTriple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer characterized by the absence of estrogen, progesterone, and HER2 receptors, which renders it resistant to hormone-based and HER2-targeted therapies. The lack of targeted treatment options, along with a high risk of metastasis and a poor prognosis, underscores the urgent need for innovative diagnostic and monitoring strategies. Current gold-standard techniques, such as tissue biopsy and imaging, exhibit limitations in capturing tumor heterogeneity and the molecular evolution of the tumor during treatment. This study proposes a clinical trial to evaluate a six-gene liquid biopsy assay for detecting DNA methylation biomarkers in TNBC patients undergoing therapy with Trodelvy. Trodelvy, an antibody-drug conjugate that targets the TROP-2 protein, delivers SN-38, a potent chemotherapy agent, directly to cancer cells. Aim 1 focuses on validating the assay for differentiating TNBC from benign and normal tissue, while Aim 2 assesses its capacity to monitor biomarker levels and detect recurrence earlier than breast MRI. Liquid biopsy, a minimally invasive and cost-effective method for analyzing circulating blood tumor biomarkers, addresses the limitations of traditional tissue biopsies and imaging. By employing quantitative methylation-specific PCR (qMSP), this study seeks to establish liquid biopsy as a sensitive and specific tool for real-time monitoring of TNBC
Salinity and Sodicity – Fundamental Points
No full textThis article, in the VegIPM Newsletter (Vol. 16, No. 18), outlines key definitions, symptoms, and management strategies for saline and sodic soils in desert agriculture, emphasizing leaching, amendments, and drainage.Documents in the Arizona Pest Management Center collection are made available by the Arizona Pest Management Center (APMC) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact https://acis.cals.arizona.edu/about-us/arizona-pest-management-center
Safety or Shelter: The Costs and Benefits of Excluding Domestic Violence Shelters from The Fair Housing Act [Note]
No full textNoteFollowing the Supreme Court’s decision in Grants Pass v. Johnson, the options for survivors of domestic violence to escape abusive situations are fewer than ever. Survivors may now be forced to choose between remaining in place or fleeing to a domestic violence shelter, possibly populated by those who resemble their abuser. To remedy this choice using existing extra-circuit case law, this Note argues that the Ninth Circuit should take a bifurcated approach when determining whether a domestic violence shelter is a “dwelling” under the Fair Housing Act. Short-term shelters—escape shelters—should not be considered “dwellings”; thus allowing shelters to be more exclusive and careful with their admission policies. Whereas longer-term shelters—rebuilding shelters—should be considered “dwellings.” Such a rule would both remove a point of hesitation for those fleeing dangerous situations and help to reacclimate those on the precipices of reentering society.This material published in Arizona Journal of Environmental Law & Policy is made available by the James E. Rogers College of Law, the Daniel F. Cracchiolo Law Library, and the University of Arizona Libraries. If you have questions, please contact the AJELP Editorial Board at https://ajelp.com/contact-us
Should Central Park Have Standing? Applying the Urban Rights of Nature Doctrine to the Urban Environmental Context [Article]
No full textArticleExpanding conceptions of legal personhood and the pressing need for creative approaches to remedying environmental damage have led to a resurgence in the Rights of Nature Doctrine. Under the Rights of Nature framework, the environment itself becomes a plaintiff with recognizable rights and causes for action. The Rights of Nature literature has thus far largely concerned itself with natural objects that are pristine and untouched, perhaps newly threatened by human activity. This Article considers how the Rights of Nature Doctrine might be adapted to the urban context, where environmental issues are almost always seen as secondary to human usage and need. It advances the premise that the heightened protection of natural spaces is compatible with human flourishing. The Article first explains the background of the Doctrine, then explores how it might be applied to urban environments like cities. The Article then proposes a rudimentary balancing test for determining when legal standing should be conferred to “natural objects” located within or near cities. Lastly, the Article considers the benefits and concerns tied to this application. As a case study, it looks at how various environmental issues in New York might have been resolved differently if the Rights of Nature Doctrine was applied.This material published in Arizona Journal of Environmental Law & Policy is made available by the James E. Rogers College of Law, the Daniel F. Cracchiolo Law Library, and the University of Arizona Libraries. If you have questions, please contact the AJELP Editorial Board at https://ajelp.com/contact-us
Precision Agrivoltaics: An Integrated Framework of Technology-Supported Agrivoltaics for Improved Crop Water-Use Efficiency, Real-Time Monitoring, and Predictive Modeling
No full textThe accelerating climate crisis has amplified pressures across the water–energy–food (WEF) nexus, intensifying challenges of agricultural sustainability, energy transitions, and freshwater scarcity, particularly in dryland regions where these stressors converge most acutely. In this context, agrivoltaics, dual land-use systems that co-locate agricultural production with photovoltaic (PV) energy generation, have emerged as a promising strategy to mitigate land-use conflicts and create synergistic benefits. This dissertation responds to critical evidence gaps in the empirical, methodological, and modeling foundations of agrivoltaics, with a particular emphasis on dryland environments. Through a combination of proximal sensing, precision irrigation experiments, and global climate–physiology integration, this body of work develops new insights and practical tools for understanding and designing agrivoltaic systems that advance both local adaptation and global sustainability goals. Chapter 1 situates agrivoltaics within the broader WEF nexus and the urgent need for synergistic solutions to climate change and sustainable development challenges. It frames drylands as both highly vulnerable and uniquely suited to agrivoltaic adoption, given their dual realities of water-limited agriculture and world-class solar resources. By tracing the conceptual development of agrivoltaics, from early proposals of co-locating crops beneath elevated PV panels to recent global expansion, the introduction identifies persistent research gaps. It highlights the limited empirical basis for crop–shade responses in arid and semi-arid regions, as well as the lack of robust physiological frameworks for global agrivoltaic suitability assessments. This framing establishes the dissertation’s core contributions: advancing empirical understanding of crop responses under dynamic shading, developing methodological innovations for monitoring and quantification, and creating a physiologically grounded global index to guide design and policy. Chapter 2 addresses the challenge of monitoring crop development in dynamically illuminated agrivoltaic systems through proximal remote sensing. Using low-cost RGB camera networks deployed at the Biosphere 2 Agrivoltaics Learning Lab, this study compares vegetation index-based segmentation methods with a state-of-the-art deep learning model (VegAnn). Results reveal that while machine learning segmentation achieved the highest per-image classification accuracy, select vegetation indices, particularly the Triangular Greenness Index (TGI), produced stable, low-noise phenological time series with minimal computational requirements. Phenological comparisons between agrivoltaic and control conditions showed broadly similar canopy development, suggesting that moderate shading did not substantially alter aboveground growth rates. This chapter demonstrates the promise of both computationally intensive and lightweight approaches for monitoring crops in shaded environments, offering practical guidance for researchers and practitioners seeking scalable monitoring solutions. Chapter 3 investigates irrigation dynamics and crop productivity under agrivoltaics through a controlled zucchini (Cucurbita pepo) cultivation experiment. A precision irrigation system was used to deliver and monitor water inputs at fine resolution, enabling direct quantification of water- and light-use efficiencies. While the system appeared to function normally, closer analysis revealed that faulty soil moisture sensors skewed median treatment values downward, inadvertently driving overwatering in agrivoltaic plots. Despite these complications, results showed that agrivoltaic treatments used up to 15% less irrigation water in high-water regimes while achieving 93% higher yields compared to the control treatment, and that even under equal water use, agrivoltaic zucchini in the low-water treatment exhibited a 97% yield increase. We go on to show the the crop-water productivity (water-use efficiency) and crop-light productivity (light-use efficiency) were greatly enhanced in the agrivoltaic treatments compared to the control, with double to triple the productivity. These findings demonstrate that moderated microclimates under PV panels can enhance water-use efficiency and crop productivity in arid systems, even when sensor reliability introduces management challenges. The chapter thus underscores both the potential of agrivoltaics to deliver genuine water savings and the importance of rigorous monitoring to implement accurate and impactful precision irrigation systems.
Chapter 4 expands the scope from field-scale experimentation to global climate integration through the development of the Agrivoltaic Productivity Index (API). Grounded in empirical measurements of photosynthesis under varying vapor-pressure deficit (VPD) and radiation regimes, the API synthesizes global climate datasets to identify regions where shading is most likely to yield agronomic benefits. Analyses reveal that agrivoltaic productivity potential is highest in drylands, where elevated VPD and radiation intensify crop stress and shading provides disproportionate physiological relief. The API highlights strong geographic contrasts, with dryland regions such as the U.S. Southwest and North Africa emerging as particularly suitable, while humid zones show limited gains. By situating agrivoltaics explicitly within climate adaptation pathways, this chapter provides a novel, physiologically grounded tool to guide siting, policy, and design strategies worldwide. Taken together, the three core research chapters advance both empirical and theoretical foundations of agrivoltaics. Proximal sensing work establishes methodological pathways for monitoring crop development in complex shading environments; irrigation experiments provide field-scale evidence of enhanced resource-use efficiencies; and the global API framework connects these insights to broader adaptation planning. Across scales, the findings converge on a central theme: agrivoltaics can enhance crop productivity and resource efficiency where pressures on the WEF nexus are greatest, particularly in drylands. This dissertation therefore contributes not only to the academic discourse on crop–microclimate interactions but also to the practical advancement of agrivoltaics as a climate-resilient land-use strategy. By integrating monitoring innovation, field experimentation, and global modeling, it offers a roadmap for harnessing agrivoltaics in service of sustainable development and climate adaptation
Synthesis and Electrochemical Analysis of Metallopolymers Containing Aryl-Bridged [2Fe-2S] Catalysts for Hydrogen Production
No full textThe increased use of renewable energy sources faces a challenge due to their intermittent output not aligning with peak energy demands. Storing this energy by producing hydrogen (H2) from water through electrolysis is a possible solution. Proton exchange membrane (PEM) electrolyzers are currently the most effective for this, partly because they adapt well to fluctuating renewable energy output. However, the reliance of PEM electrolyzers on expensive metals like platinum and iridium for electrodes necessitates the search for more affordable alternatives. Small molecule catalysts inspired by the [FeFe]-hydrogenase active site show promise for the hydrogen evolution reaction (HER), but they struggle with oxygen instability, degradation, and poor water solubility.Previous research in this group led to the discovery of metallopolymer catalysts that overcome these limitations by covalently binding a polymer to the small molecule catalyst. These metallopolymers demonstrated superior HER catalysis in neutral aqueous solutions, greatly outperforming previous small molecule catalysts and even rivaling platinum at extremely low catalyst loadings (1-2 ppm) with less than 0.2V overpotential difference. Further research has explored how polymer composition and buffer choice influence catalytic output. The contributions of this dissertation aim to further our understanding of these metallopolymer catalysts by investigating how molecular weight limits catalysis, how the topology of the [2Fe−2S] catalyst site impacts output, and how azide-containing monomers can enhance functionality through click chemistry. When studying metallopolymer catalysts of different sizes, it was anticipated that smaller metallopolymers would have faster rates due to faster electron and proton transfers to more accessible active sites. However, the experiments show that the rates of catalysis per active site are independent of the polymer size, as it was discovered that the high performance is due to adsorption of the metallopolymer on the electrode surface, bringing the [2Fe−2S] catalytic sites into close contact with the electrode surface while maintaining exposure of the sites to protons in solution. The assembly is conducive to fast electron transfer, fast proton transfer, and a high rate of catalysis regardless of the polymer size. By designing a new metalloinitiator small molecule, the topology of metallopolymer catalysts was controlled, placing the [2Fe-2S] active site internal (in chain) or terminal (endgroup) in the polymer network. By comparing electrochemical performance of metallopolymer catalysts with the same composition, but with different topological active site placement, it was determined that the metallopolymer catalysts showed comparable current densities, Langmuir adsorption, and electronic limits. The adsorption of the metallopolymers to the electrode surface creates similar chemical environments for electrolysis, establishing that the active site can be placed anywhere that is most convenient in the metallopolymer topology without loss of performance. Through the incorporation of a methacrylic monomer with an azide pendant chain, a new synthetic methodology to functionalize [2Fe-2S] metallopolymers using atom transfer radical polymerization (ATRP) and post-polymerization functionalization using azide−alkyne “click” cycloaddition was developed. [2Fe-2S] metallopolymers were prepared by the ATRP of 3-azidopropyl methacrylate (AzPMA) with either methyl methacrylate (MMA) or 2-(dimethylamino)ethyl methacrylate (DMAEMA), followed by copper-catalyzed “click” cycloaddition. These metallo-copolymers were found to retain Fe−CO bonds from the catalyst active site after the click chemistry reactions and, more importantly, retained electrocatalytic activity under pH-neutral aqueous conditions
Soil Monologues: Critical Ecotones of Pollution, Health, and Justice
No full textResource extraction and resultant pollution and socioecological harm are rooted in settler colonial Land relations. Through disproportionate pollution exposure and vulnerability, the State is largely responsible for creating environmental justice communities. This dissertation is concerned with the pollution experience of marginalized peoples primarily in rural Arizona in three main ways: 1) the quality and safety of rooftop harvested rainwater, garden soil, and garden plants, 2) the human health risks from metal(loid) contamination of garden plants and soil and guidelines for their continued use, and 3) the environmental health literacy and collective action of youth living in environmental justice communities. We used frameworks of community science, critical environmental justice, anti-colonial pollution science, and political education to conduct and analyze participatory research efforts from 2010 – 2025 with the goal of understanding and alleviating environmental injustices. We observed that rooftop harvested rainwater in Arizona is largely safe for irrigation. Garden soils and plants grown and consumed in environmental justice communities pose a health risk from contaminants such as arsenic and manganese, but not substantially more than conventionally grown produce. We were able to calculate place-based risk-based soil and plant screening levels and plant ingestion rates to inform community agricultural practices and consumption. Finally, we observed that informal science youth trainings in rural Arizona successfully increased youth environmental health literacy and illuminated obstacles to youth action such as adultism, critical consciousness, and a culture of silence. Future work will continue to explore how a critical, anti-colonial pollution science can support ending systems of oppression to truly achieve environmental justice
Cis Lunar Surveillance System
No full textIn an era defined by accelerated human and robotic ventures beyond low–Earth orbit and an increasing imperative to detect, track, and characterize transient near–Earth objects, this thesis presents a transformative concept: a distributed cis–lunar surveillance constellation that leverages the intrinsic dynamical pathways of the Earth–Moon three–body environment to achieve persistent, low–energy monitoring and rapid intercept capabilities. Drawing upon the rich structure of halo orbits and their associated invariant manifolds, our design embeds a network of microsatellites in carefully chosen manifold–guided trajectories, minimizing station–keeping ∆V while maximizing spatial coverage of the cis–lunar arena. The constellation’s hardware architecture integrates high–resolution optical imagers, wide–band radio–frequency transceivers, and autonomous inter–satellite ranging instruments, all orchestrated through a decentralized liaison framework that distributes processing and decision authority across the network. To navigate the complex gravitational interplay in the Circular Restricted Three–Body Problem without continuous ground intervention, we develop a passive measurement strategy that fuses star–line and inter–satellite range observations within an Unscented Kalman Filter tailored to the nonlinearities of the CR3BP, thereby achieving real–time, fault–tolerant orbit determination and guidance. We demonstrate the system’s rapid–response potential through a detailed case study: an opportunistic flyby and subsequent rendezvous with the temporary moon 2020 CD3. Beginning
from a nominal halo–orbit constellation configuration, our transfer optimization—formulated as a constrained two–point boundary-value problem—yields a total ∆V of approximately 1.75km s−1, on par with dedicated singular missions yet accomplished without extensive pre–mission planning or large payload capacity. Monte Carlo simulations confirm a > 95% probability of intercept within a 1km corridor, and covariance analysis indicates sub–10m positional uncertainty at rendezvous, sufficient to support high–resolution imaging, in–situ sampling, and autonomous proximity operations. Beyond validating the concept, these results underscore manifold–enabled cis–lunar constellations as cost–effective, scalable platforms for planetary defense, resource reconnaissance, and sustained lunar exploration objectives. By uniting advanced astrodynamics, distributed sensing, and autonomous navigation, this work lays the foundation for a resilient space situational awareness infrastructure that can adapt to evolving threats and opportunities across Earth–Moon space
PREVALENCE OF INTESTINAL PARASITES AND ANTI-HELMINTH RESISTANCE IN FERAL POPULATIONS IN ARIZONA
No full textSemi-managed animal populations, such as barn cats and feral donkeys, occupy a unique space between domestic care and environmental exposure, placing them at ongoing risk for gastrointestinal parasite transmission. This thesis evaluated parasite prevalence, diagnostic method performance, and management implications in barn cats and rescued feral donkeys across Arizona. Fecal samples from barn cats (n=22) were analyzed using both passive flotation and centrifugal flotation (CFS) methods. Results yielded a prevalence of 9.1% Hookworms and 0% prevalence for remaining parasites. All positive cases were detected using CFS, while passive flotation failed to identify any infections. An intraclass correlation coefficient (ICC) analysis demonstrated low agreement between tests (ICC = -2.3 × 10^-15; 95% CI: -0.400 to 0.408), suggesting the two methods produced inconsistent egg count results overall. These findings highlight the importance of selecting sensitive diagnostic tools when screening semi-managed feline populations with low to moderate parasite burdens. Donkey fecal samples (n=36) were examined using the Modified Wisconsin and McMaster techniques to quantify strongyle-type and ascarid eggs. Strongyles were the most prevalent, with 63.9% of samples testing positive across both methods. Ascarid detection ranged from 22.2-38.9%, depending on method. The Cliff's Delta value was -0.25, indicating a small negative effect size, meaning that the Modified Wisconsin method tends to underestimate Ascarids compared to the McMasters. Additionally, the Bland-Altman plot for Ascarids revealed this negative bias appeared to increase with higher Ascarid counts, showing a proportional underestimation by Wisconsin for larger counts. After administration of oral Ivermectin, the Fecal Egg Reduction Count Test revealed 100% reduction for Ascarids and 0% for Strongyles, revealing evidence of Ivermectin resistance in Strongyles. These findings emphasize the need for species-specific diagnostic strategies, tailored deworming protocols, and regular resistance monitoring in semi-managed animal populations