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Spider Mites in Desert Melons
No full textAn extension-style IPM factsheet addressing biology, identification, seasonal risk, and control of twospotted spider mites (Tetranychus spp.) in desert-grown melons. This document highlights damage symptoms, optimal environmental conditions for outbreaks, beneficial arthropods, and current miticide options (e.g., Agri-Mek, Oberon, Zeal). The factsheet is particularly useful for melon producers seeking sustainable, selective pest management recommendations during periods of high mite pressure in arid climates.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
UNDERSTANDING IMPACTS OF SEVERE WILDFIRE TO ARIZONA MOUNTAIN FOREST: AN ANALYSIS OF 2 LARGE WILDFIRES IN THE MADREAN SKY ISLANDS
No full textTwo large and destructive wildfires, the Frye Fire (2017) and the Bighorn Fire (2020), occurred within two mountain ranges within the Arizona Madrean Sky Island ecoregion, the Santa Catalina Mountains and Pinaleño Mountains respectively. Both wildfires are described by varying degrees of burn severity, each consuming large portions of high elevation (> 7000 ft) coniferous forest following previous large and destructive stand replacing wildfire events within similar footprints. Given the immense transition in forest type and structure across drastic elevational gradients unique to these mountain ranges, there is a need to understand the relative recovery associated with Sky Island forest structure following large mountain-wide fire events. Providing 1) a visual representation of localized precipitation conditions prior to the wildfire events, 2) a remote sensing index driven fire effects analysis, and 3) a change detection analysis to forest structure, may help to better understand trends of wildfire to these unique ecosystems. Using Sentinel-2 derived satellite imagery, a series of spectral indices (Normalized Difference Vegetation Index, Normalized Burn Ratio Plus, Normalized Difference Infrared Index, and Burn Area Index for Sentinel-2) were calculated to identify burn severity, vegetation loss and 5-year post fire recovery potential to provide more accurate estimates to areas most likely to have undergone forest type conversion.This item is part of the MS-GIST Master's Reports collection. For more information about items in this collection, please contact the UA Campus Repository at [email protected]
Economic Evaluation for the US of the Novel Tyrosine Kinase Inhibitor Ponatinib Versus Reference and Generic Imatinib in Front-line Management of Philadelphia Chromosome–Positive Acute Lymphoblastic Leukemia
No full textObjective: Ponatinib, a third-generation tyrosine-kinase inhibitor (TKI) demonstrated greater efficacy compared to imatinib, a first-generation TKI, in the PhALLCON trial. This study aimed to conduct an economic evaluation of ponatinib compared to reference imatinib (Gleevec®), the average cost of several imatinib generics and the weighted cost of imatinib respectively, in the treatment of patients with Philadelphia chromosome-positive Acute Lymphoblastic Leukemia (Ph+ ALL) from the US payer perspective.
Methods: Cost-effectiveness and cost-utility analyses were performed using a partitioned survival model with three mutually exclusive health states—progression-free, progressed disease, and death. A time horizon of 60 months and a 3% discount rate were applied. The incremental costs per 1% gain in probability of progression-free survival (PFS) and overall survival (OS) at 60 months were estimated.
Results: The exponential distribution was deemed the best fit for both PFS and OS in both treatment arms. LYs and QALYs were higher for ponatinib (3.74, 2.15) than imatinib (3.52, 1.68). Using Gleevec® as a reference, ponatinib had cost savings of 147,147, an ICER and ICUR of an additional 314,646 per LY and QALY gained respectively compared to average generic imatinib. For weighted imatinib, ponatinib had an incremental cost of 585,122 and 6,883 compared to Gleevec®, 15,831 compared to the weighted imatinib.
Conclusion: Ponatinib demonstrated cost savings relative to Gleevec®, though its incremental costs were substantially higher when compared to both average and weighted imatinib. Given that 91% of prescriptions are generic medications, payers and policymakers must weigh the clinical benefits of ponatinib in improving survival against its financial implications.Release after 04/28/202
Hippocampal Representations of Time and Length During Fine Motor Behavior, and Alpha-Synuclein Drives Basal Ganglia Modulation in a Zebra Finch Parkinsonian Model
No full textThe hippocampus is an integral structure for the construction and recollection of memory in both humans and non-human species. Since the mid-20th century, extensive work has elucidated its cellular responses to movement that form a robust foundation for spatial memory. The advent of in vitro recordings provided an in-depth understanding of how groups of neurons and single units in the hippocampus coordinate to form stable memories across the lifespan. Early discoveries using local field potential illustrated the importance of the hippocampal theta (4-9 Hz) oscillation in memory formation, and how its presence during movement orchestrates reliable activity of neurons representing spatial information. Hippocampal time cells were later discovered that responded to brief segments of time, which are believed to support the temporal properties of episodic memory. The first study of this thesis provides insight into how hippocampal theta oscillations differ among spatial navigation relative to fine-motor locomotion. The second follow-up study sought to elucidate whether hippocampal neurons can flexibly map onto segments of time and centimeters of string pulled (length) during a fine-motor behavior. In the first study, we found opposing responses in theta frequency and power between spatial navigation and fine-motor locomotion. While theta frequency and power were positively related to spatial navigation speed, theta oscillations were reduced to a lower frequency while power increased with fine-motor speed. The ‘pull’ and ‘push’ paw motions (associated with advancing an animal through space) were positively related to theta frequency and power and were phase locked to theta. The second follow-up investigation found hippocampal activity during discrete segments of time and a novel dimension of the ‘length’ during fine-motor behavior. These results illustrate how the hippocampus may differentially support the perception of movement through space and fine-motor behavior, and how it flexibly responds to abstract dimensions beyond traditional 2D navigation.The final study presented in this thesis explored the neuronal correlates of vocal deficits by classifying the activity of cell types in Area X, a song nucleus of the avian basal ganglia (BG), in an anesthetized zebra finch adeno-associated virus (AAV) model of Parkinson’s disease (PD). In the early 20th century, it was established that the motor deficits in PD stem from degeneration in the BG. While vocal dysfunctions are the first symptoms of PD and present prior to the onset of tremors, little is known of the neural substrates underlying early vocal symptoms. An analysis of the two neuron classes, putative medium spiny neurons and pallidal neurons, revealed reduced firing rates and alterations in waveform shape, which could indicate changes in membrane-bound channels, in both cell types among AAV animals relative to controls. These results suggest that reduced firing rate and alterations to intrinsic membrane excitability may contribute to the early vocal deficits observed in PD. Collectively, these findings reveal novel hippocampal responses to limb movement and segments of length during fine-motor behavior, and suggest that neuronal modulation in the BG may underlie vocal motor impairments observed in early PD.Release after 12/10/202
Risk and Rainfall: Specification Sensitivity in Estimating Smallholder Risk Preferences
No full textRainfall variability in Sub-Saharan Africa creates significant production risks for subsistencefarmers who rely on rainfed agriculture. Weather shocks can alter farmers’ risk preferences,
potentially influencing their decision to adopt adaptation strategies. We employ a moments-
based approach (Antle, 1983, 1987) to estimate risk aversion among smallholder farmers in
Ethiopia, Malawi, and Nigeria in response to weather shocks. Using this framework, we esti-
mate Arrow-Pratt and downside risk coefficients across more than 200 model specifications,
incorporating various rainfall and rainfall shock metrics derived from six remote sensing
weather products. Our findings reveal that estimates of farmers’ risk preferences are highly
sensitive to the choice of weather product, while risk preferences are relatively insensitive to
different weather shocks. This underscores how data source and model specification choices
critically shape risk preference estimates, highlighting key limitations in current empirical
methods
Targeting Performance of SWIR/MWIR Superband Camera Systems
No full textWith the improvement of infrared detector technology over the last several decades, traditional design trades regarding the use of different wavebands in optical systems are becoming less and less applicable. New detector technology allows for extended and even bridged wavebands, where previous detectors were limited to only a single waveband. These bridged waveband cameras, or superband cameras, contain detectors with response over large spectral spans, allowing them to take advantage of the unique properties of multiple wavebands. This type of system is especially of interest when the superband contains both the short-wave infrared (SWIR) waveband – where most of the signal comes from reflected light – and mid-wave infrared (MWIR) waveband – where most of the signal comes from emitted light. It is commonly understood that in many cases, having more spectral information leads to an increased ability to complete discrimination tasks on a target within a scene. This is only true, however, when the optical system has been designed to take advantage of the additional spectral information and the information that spectral content adds is understood. Such a superband system allows the combination of information and signal from reflective and emissive sources, not only in a single system, but on a single detector. These superband systems have the capability to open new system level optical design trades across many fields and disciplines. It is therefore essential that the capabilities of these new superband systems be understood so optical system designers can have a complete toolbox of all potential design possibilities.To better quantify the performance of these superband detectors, it is extremely important that the system be analyzed in many ways, to allow for understanding not only in where these systems work well, but also in where they do not provide benefit over traditional systems, what their practical limitations are, and how they should be properly designed to maximize their performance. Therefore, multiple superband systems were analyzed via modeling and field tests to capture the complete picture of their performance. The first step in this performance characterization is to understand the radiometry that defines a superband system and how the total signal received by these systems is divided between the reflective and emissive sources in the scene. The second step is to then build an understanding of how the signal from each type of source contributes to the overall information in the scene and under what situations do the different sources provide new, complementary information and under what situations do the sources provide similar, redundant information. With this knowledge, the next step is to define and compare the resolution and sensitivity of a superband system to a SWIR, extended SWIR (eSWIR), and MWIR system of the same design parameters. Finally, the last step is to understand how the overall targeting performance of a superband system varies as those aforementioned design parameters change and how to adjust them to maximize the targeting performance for the system. Through camera modeling and field tests, the superband systems were shown, in each step, to provide superior performance to MWIR systems during the day due to the addition of the SWIR and eSWIR short wavelength signal. The modeling and tests also showed that the superband system outperformed the SWIR and eSWIR systems under low light imaging conditions due to the longer wavelength MWIR signal. Thus, the superband system was shown to provide a unique design option where high-resolution, long-range targeting is required but low light performance cannot be sacrificed. By proper design of a superband system, both capabilities are possible
AstroDB Data Extraction: A Comparative Analysis of Embedding, Query Expansion, and Filtering Techniques
No full textDue to the rapid growth of astrophysical scientific papers, it is difficult to extract important data manually from the scientific papers. While traditional search engines can help to find relevant publications, they may not be able to capture the numerical and contextual details of significance. This thesis explores the multi-modal data extraction in the AstroDB. The accuracy, LLM token usage, and run time of various combination extraction methodologies are compared in this study to reveal key precision versus computational efficiency trade-offs. These insights provide a way to improve the data extraction pipeline and accelerate scientific discovery in astrophysics
Exploring Crop Yield Dynamics Across Sub-Saharan Africa: A Six Country Study
No full textMillions of people rely on agriculture for their livelihoods and it is the backbone of the economy in many developing countries. Improving agricultural yields is widely recognized as a key strategy for reducing poverty and ensuring food security around the globe. This paper examines agricultural productivity trends and the factors influencing them between 2008 and 2021 in six Sub-Saharan African countries. We estimate six models across different levels of aggregation (plot, household, manager, and cluster) to assess changes in productivity over time. Our findings show no evidence of yield growth or improvement, with agricultural productivity remaining unchanged across levels over time. Our results also suggest that while agricultural inputs are associated with higher yields, household characteristics and plot manager traits are linked to less favorable outcomes, which could help explain the lack of yield improvement. These findings contribute to ongoing discussions about which policy tools can best support smallholder farmers in Sub-Saharan Africa in increasing agricultural productivity
Integrating Behavioral and Equity Factors to Enhance Transportation Safety
No full textRoad safety remains a global challenge, with persistent disparities in risk exposure and outcomes across demographic groups. This dissertation investigates key dimensions of equity in road safety through a series of interconnected studies that integrate behavioral analysis, equity assessment, and advanced analytical methods. It begins with an alert study that examines behavioral differences in driver performance, uncovering variations in response times and distances across male and female drivers. These findings provide insights for improving roadway design based on behavioral differences. The research then applies explainable artificial intelligence (XAI) to analyze disparities in injury severity outcomes and crash risks, revealing that existing safety measures often overlook the specific needs of communities. To evaluate safety performance across regions and demographics, the study then applies data envelopment analysis (DEA), which generates efficiency scores that reflect how effectively jurisdictions convert safety inputs into reduced crash risks. This approach also identifies inequities in safety outcomes across different populations. A complementary investigation then explores the use of retrieval-augmented generation (RAG) systems to enhance the analysis of complex transportation safety datasets and documents. The findings consistently demonstrate that road users are not a homogeneous group. Differences in crash risk between different demographic groups highlight the importance of context-specific safety strategies. Rather than relying on uniform solutions, safety interventions should be tailored to reflect the unique behaviors and risk profiles of different demographic groups. This dissertation argues that equity in transportation safety should be grounded in the level of crash risk exposure and its consequences. Overall, the research contributes both conceptual insights and practical tools to support the design of safer and more equitable transportation systems, offering direction to practitioners, researchers. and policymakers aiming to reduce disparities through evidence-based strategies.Release after 07/01/202
Examining production of municipal solid waste for bulk pickup and median household income in Tucson, Arizona
No full textSustainable Built Environments Senior Capstone ProjectThe relationship between socioeconomic factors like median household income and behavior tied to the production of bulk waste has important ramifications for improving municipal waste management systems. This study investigates this relationship among different neighborhoods in the city of Tucson, Arizona. Using direct observation methods in 18 neighborhoods of varying income levels within six waste management districts across the city, this study identifies the physical manifestation of the role household income plays in the production of bulk waste. Observation routes were designed in each of the 18 neighborhoods, keeping the number of parcels in each route constant for consistency. Observations recorded the amount of individual piles of trash placed on the side of the road for pickup, with a unit defined as a pile at least one square meter in size, no more than 10 cubic meters in volume, and at least three feet apart from other piles as defined by the city of Tucson. The study found that neighborhoods with a higher median household income produced more trash than those with lower income levels. This could be due to wealthier households having more disposable income that allows them to purchase more items that will eventually be discarded, that wealthier households move homes more frequently and thus need to discard furniture and appliances more frequently, or that wealthier households have more resources to undergo home renovations and therefore discard more bulk waste in the form of furniture, appliances, and building materials. Based on these results, practical applications of the data are discussed as they pertain to improving local waste management policies and strategies for waste reduction. Future studies should examine all 26 waste management districts and the types of waste produced.This item is part of the Sustainable Built Environments collection. For more information, contact http://sbe.arizona.edu