Life Sciences Commons^™

Essays On The Economics Of Farmland Valuation And Investment In U.S. Agriculture, Colson Tester

Graduate Theses and Dissertations

This dissertation presents three empirical essays that collectively advance the understanding of farmland valuation in key U.S. agricultural regions, emphasizing the critical advantages of comprehensive, transaction-based data over traditional survey methods. Farmland represents a significant portion of agricultural wealth, and its accurate valuation is crucial for farmers, investors, and policymakers, influencing everything from credit access to investment strategies. Historically, research has often relied on subjective survey data, which can suffer from biases, inaccuracies, and insufficient granularity. This dissertation addresses these limitations by leveraging extensive datasets of arm’s-length farmland transactions, offering a more precise and market-driven perspective on land values. The …

Twim #261: Overwhelming Microbial Greatness, Jenny Stoval, Briana Lanzarotta, Luke Boseman, Nicole L. Podnecky, Angela Wilson

School of Medical Diagnostics & Translational Sciences Publications

Podcast annotation TWiM #261: Overwhelming Microbial Greatness from the weekly podcast series "This Week in Microbiology" (TWiM), a podcast where experts in microbiology discuss academic papers in their field in an informal way.

Impacts Of Nutrient Addition And Disturbance On Coastal Dune Arthropod Communities And Trophic Interactions, Kayla Beitzel

Graduate Theses and Dissertations (2019 - present)

Coastal dune ecosystems face ongoing threats from human-mediated disturbance and altered resource availability. Because these dunes provide critical habitat for many organisms, including shorebirds, beach mice, and arthropods, changes in disturbance regimes or resource availability can impact plant communities and higher trophic levels by altering plant richness and productivity, which in turn influence arthropod abundance and diversity. To examine how disturbance and nutrient addition affect arthropod communities, we established twenty 5×5 m plots on Dauphin Island, crossing mechanical disturbance with a 10 g m⁻² addition of nitrogen, phosphorus, and potassium, replicated across five experimental blocks. Arthropods were sampled using three …

Performance Enhancement For Rufa: Rapid Urban Forest Assessment, Nicholas Tan

Master's Theses

Urban forests are crucial to the livability and resilience of cities, offering critical ecosystem benefits such as air quality enhancement, temperature regulation, and biodiversity. Managing said urban forests is essential to ensure their sustainability and adaptability to rapidly changing environmental and climate conditions. The Rapid Urban Forest Assessment (RUFA) tool was developed to address the need for a standardized approach to evaluating and comparing urban and community forestry programs. By analyzing and aggregating tree-specific data across California, such as canopy cover, tree counts, and diversity scores, RUFA assigns a comprehensive urban forestry score for each city. This score allows for …

Flower Color Variation And Its Maintenance: Experimental Ecology Of Serpentine-Adapted Leptosiphon Parviflorus Benth. (Polemoniaceae), Magdalene S. Lo

Master's Theses

Environmental heterogeneity can impose fluctuating selection pressures on species across space and time. If variations of a trait provide fitness benefits in certain environmental conditions but not others, these fitness tradeoffs under fluctuating selection could be a means of maintaining intraspecific variation. A common type of intraspecific variation is the production of anthocyanins, pigments responsible for red, pink, and blue colors in plants and that can also provide protection from abiotic stressors, such as water limitation and heavy metals. Leptosiphon parviflorus Benth. (Polemoniaceae, variable linanthus) is an annual wildflower whose individuals produce either pink or white flowers, and both flower …

Abiotic Stress Impacts On Macrophomina Root Rot And Nano-Encapsulated Citrus Oils To Control Fruit And Foliar Pathogens Of Strawberry, Marina J. Gutierrez

Master's Theses

Disease remains one of the major constraints to the productivity and economic success of the California strawberry industry. The most important soilborne pathogen is Macrophomina phaseolina, causing Macrophomina root rot (MRR). The most economically significant airborne pathogens include Botrytis cinerea, causing Botrytis fruit rot (BFR), and Podosphaera aphanis, causing powdery mildew (PM).

Disease severity of MRR is highly dependent on environmental factors. Therefore, understanding which abiotic stressors contribute most to disease development is crucial for effective management. A two-year field experiment at Cal Poly, SLO (2024 and 2025) evaluated the effects of drought stress, two elevated chloride …

Sleep-Disordered Breathing Subtypes And Future Diet Quality In The Multi-Ethnic Study Of Atherosclerosis, Kaitlin S Potts, Cecilia Castro-Diehl, Tianyi Huang, Alexis C Wood, Jerome I Rotter, Stephen S Rich, Tamar Sofer, Susan Redline, Heming Wang

Children’s Nutrition Research Center Staff Publications

Objectives: Sleep-disordered breathing (SDB) and diet quality impact cardiometabolic disease, but few studies have examined if SDB influences diet quality. This study estimated the association between SDB subtypes (with and without sleepiness) and future diet quality in the Multi-Ethnic Study of Atherosclerosis.

Methods: Probable SDB was characterized by self-reported physician-diagnosed sleep apnea (PDSA) or habitual snoring and subtyped by presence or absence of sleepiness. A food frequency questionnaire measured diet 1.6 years before, and 7.8 years after SDB assessment. Diet quality was measured with the Alternate Healthy Eating Index-2010 (AHEI). Mean differences in AHEI at follow-up by SDB subtypes were …

Differences In Total Daily Energy Expenditure Across Field Sports: A Narrative Review, Brenen Skalitzky, Jennifer Fields, Margaret T. Jones, Chad Kerksick, Andrew Jagim

Faculty Scholarship

Background: Differences in total daily energy expenditure (TDEE) across sports, sex, and skill level support the need for sport- and athlete-specific energy intake recommendations. The purpose of the current review was to examine TDEE and related markers of energy expenditure across field-based team sports. A secondary aim was to evaluate physical activity levels (PAL), calculated as TDEE divided by resting metabolic rate (RMR), and their utility in estimating energy needs within team sports.

Methods: The review was limited to studies that included the field-based team sports of rugby or soccer and reported energy expenditure data using doubly labeled water …

Synthesis Of Antibody Functionalized Polyaniline/Polystyrene/N-Gqds Composite Fibermats For Sweat Based Cortisol Biosensing Applications, Ashwin James

Honors Theses

Noninvasive, wearable biosensors capable of detecting stress biomarkers in sweat require electrodes that are flexible, conductive, insoluble in water, and highly sensitive at low concentrations of analyte. In this work, bovine serum albumin blocked and anti-cmab immobilized nitrogen doped graphene quantum dots integrated polyaniline/polystyrene composite fibermat electrodes (BSA/Anti-Cmab/N-GQDs/PANI/PS electrodes) were synthesized and evaluated as a potential platform for an electrochemical cortisol biosensor in sweat based systems. Polyaniline was utilized in order to provide electrical conductivity, while polystyrene served as a carrying polymer for mechanical support and its hydrophobicity. Composite fibermats were manufactured through Forcespinning™, followed by a secondary polyaniline graft …

Ongoing Recovery Measurements In Kwinana Shelf Seagrass Meadow In Cockburn Sound 2.5 Years Post Impact Phase To Give Greater Confidence In Recovery Data And For Eia Monitoring, Nicole Said, Chanelle Webster, Simone Strydom, Kathryn Mcmahon

Research outputs 2022 to 2026

Executive summary: Understanding the nature of interactions between multiple stressors is essential for assessing their cumulative impacts on seagrasses and for guiding effective management. Current dredging thresholds are based largely on single stressors (light reduction or sediment burial), despite pressures typically co-occurring, and these thresholds may therefore need refinement to account for interactive effects. In addition, recovery times under single and multiple pressures remain a major knowledge gap, further reducing our ability to accurately predict impacts and implement effective management. This need is particularly pressing in regions facing ongoing dredging pressure. Cockburn Sound, which has already lost ~75% of its …

De Novo Annotation Reveals Transcriptomic Complexity Across The Hexaploid Wheat Pan-Genome, Benjamen White, Thomas Lux, Rachel Rusholme-Pilcher, Angéla Juhász, Gemy Kaithakottil, Susan Duncan, James Simmonds, Hannah Rees, Jonathan Wright, Joshua Colmer, Sabrina Ward, Ryan Joynson, Benedict Coombes, Naomi Irish, Suzanne Henderson, Tom Barker, Helen Chapman, Leah Catchpole, Karim Gharbi, Utpal Bose, Moeko Okada, Hirokazu Handa, Shuhei Nasuda, Kentaro K. Shimizu, Heidrun Gundlach, Michelle L. Colgrave

Research outputs 2022 to 2026

Wheat is the most widely cultivated crop in the world, with over 215 million hectares grown annually. The 10+ Wheat Genomes Project recently sequenced and assembled to chromosome-level the genomes of nine wheat cultivars, uncovering genetic diversity and selection within the pan-genome of wheat. Here, we provide a wheat pan-transcriptome with de novo annotation and differential expression analysis for these wheat cultivars across multiple tissues. Using the de novo annotations we identify cultivar-specific genes and define the core and dispensable genomes. Expression analysis across cultivars and tissues reveals conservation in expression between a large core set of homeologous genes, in …

An Investigation Of The Characteristics And Uses Of School Farms In California Ffa’S Superior Region, Emily R. Fuller, Jessica M. Toombs

Journal of Research in Technical Careers

This study investigates the characteristics and uses of school farms within Northern California, focusing on their role in school-based agricultural education (SBAE). The research aims to determine the structural and operational attributes of these facilities and to identify their primary uses as experiential learning tools. Utilizing a descriptive survey design, data were collected from 74 agricultural educators. Findings reveal that school farms, averaging 21.27 acres, are predominantly managed by agriculture teachers and are primarily used for housing market animals, supporting Supervised Agricultural Experience (SAE) projects. The study highlights the need for diversified school farm facilities to enhance experiential learning across …

Associations Between Food Insecurity And Gpa Among Full-Time California State University Undergraduates During Covid-19: The Impact Of Mental Health, Lindsey Jones

Master's Theses

Food insecurity is a persistent public health concern among college students that has been associated with student’s academic and mental health outcomes. This thesis examined the associations between food insecurity, academic performance (measured by GPA) and mental health (using Kessler 6 psychological distress and self-perceived mental health impacts on academic performance), among full-time undergraduate students within the California State University (CSU) system. Cross-sectional analyses were conducted using data from the Spring 2021 CSU National College Health Assessment, administered across all 23 campuses. Of the 20,167 respondents, 12,899 students were included in the analytical sample. Bivariate analyses were conducted to analyze …

Flux Crystal Growth Of A Series Of Calcium Rare Earth Silicate Chlorides Calnsio4Cl (Ln = Pr, Nd, Sm, Eu, Gd, And Tb): Mixed Anion Materials With A Spodiosite-Type Structure, Maria Goncalves, Mark D. Smith, Hans Conrad Zur Loye

Faculty Publications

A series of calcium rare earth silicate chlorides, CaLnSiO4Cl (Ln = Pr, Nd, Sm, Eu, Gd, and Tb), was obtained as single crystals from flux crystal growth. The structures were determined by single crystal X-ray diffraction and were found to be related to the spodiosite/Wagnerite mineral structure, Ca2PO4F. The obtained compositions are variations of the spodiosite structure that result from two simultaneous elemental substitutions. Replacing one calcium for one rare earth element and the simultaneous replacement of one VO4³⁻ or PO4³⁻ with one SiO4⁴⁻. CaEuSiO4Cl was found to luminesce, and its photoluminescence spectrum is reported.

Water Circulation Beneath A Hovering Suas For Water Quality Monitoring Applications, Erin E. Hackett, Boone Fleenor, Jensine C. Coggin, Duvall Dickerson-Evans, Nikolaos Vitzilaios, Whitney E. Schuler, Paige K. Williams, Michael L. Myrick

Faculty Publications

Water quality has traditionally been measured via in situ sensors and satellites. The latter has limited applicability for smaller inland water bodies, while the former requires significant logistics, labor, and expense for routine sampling, and reactive/spurious sampling is often not feasible as a result (e.g., sampling pre-/post-storm). Consequently, small uncrewed aircraft system-based (sUAS-based) sampling has emerged as a potential solution to bridge these sampling gaps and challenges. But sampling from an sUAS is complicated by the need to pump water from depth, rather than suspending a sensor from the sUAS, due to concern over sampling sUAS-impacted waters. Here, we measure …

Thermodynamic Assessment Of The Li, Na, K, Cs | F, I Reciprocal Salt For Msr Applications, Clara M. Dixon, Mina Aziziha, Amir Mofrad, Jorge Paz Soldan Palma, Ronald E. Booth, Aiswarya Padinhare Manissery, Jack A. Wilson, Hans Conrad Zur Loye, Hunter B. Tisdale, Juliano Schorne-Pinto, Theodore M. Besmann

Faculty Publications

Gibbs energy models necessary to describe the thermochemical behavior of cesium and iodine in molten FLiNaK (46.5LiF-11.5NaF-42KF mol%), a proposed molten salt reactor coolant and fuel solvent, have been developed as they are of concern due to their high radiotoxicity and volatility. The six constituent pseudo-binary systems LiI-CsI, LiI-KI, LiI-NaI, NaI-KI, KI-CsI and NaI-CsI were evaluated using available phase equilibria and mixing enthalpy measurements. The models for the ternary reciprocal salt systems Li,Cs|F,I, Li,K|F,I, Li,Na|F,I, Na,K|F,I, Na,Cs|F,I and K,Cs|F,I were obtained by interpolation of the optimized pseudo-binary systems and parameters fit as necessary based on observed behavior. The additive (common …

Investigating The Levels Of Burnout Of New Extension Agent Hires Throughout Their First Employment Year, Matt Benge, Amy Harder, Lendel K. Narine

Journal of Human Sciences and Extension

The objectives of this paper were to describe new Extension agent hires’ levels of burnout during their first year on the job, and to determine if there are significant predictors for burnout based on new Extension agent hires’ gender and age. We implemented a longitudinal quantitative research design using the Maslach Burnout Inventory to measure burnout with 58 new Extension agent hires. Survey data were collected monthly throughout the new agents’ first year on the job. New Extension professionals’ burnout levels did increase over the course of their first year on the job. Female agents experienced slightly higher levels of …

Let’S Talk Mental Health: An Assessment Of Oregon Agricultural Stakeholders Discussing Mental Health, Whitney Stone, Lauren Chase, Taylor Foerster

Journal of Human Sciences and Extension

Working in agriculture presents some unique mental health stressors, including financial difficulties, climate variability, and isolation. Currently, Extension offers mental health literacy programming addressing mental health and suicide in agricultural communities; however, some of the programming is underattended, and resources are underutilized. We sought to find out how communicating about mental health resources was perceived by agricultural stakeholders who work closely with farmers and ranchers, including agribusiness employees, leaders in the community, and pre-service agriculture teachers. Through this mixed-method study using focus groups and a survey, we wanted to find out the perceptions of mental health resources to help inform …

Rural Mental Health Challenges: Addressing Community-Specific Needs Of Rural Mississippians, Mary Marshall Waller, Mary Nelson Robertson, Holli H. Seitz, Michael R. Nadorff, David R. Buys

Journal of Human Sciences and Extension

America’s mental health crisis uniquely impacts rural areas. Challenges surrounding intention and accessibility to engage in mental health-fostering behaviors exacerbate disparities in rural mental healthcare. In this study, Cooperative Extension personnel assess rural Mississippians’ intention to engage in mental health-fostering behaviors, accessibility to mental health-fostering behaviors, and helpfulness of increased access to resources for mental health challenges to determine if relationships exist between these variables. Rural Mississippi adults were recruited via an online survey panel to complete a 147-item web-based questionnaire (n = 274). Findings suggest rural adults’ intention to engage in mental health-fostering behaviors favored connecting with family and …

The Effects Of The Cooking For One Curriculum On Nutrition, Food Safety, Food Resource Management, And Physical Activity Behaviors: A Pilot Study, Tyler B. Becker Dr., Ronald L. Gibbs Jr, Becky Henne, Erika Garner

Journal of Human Sciences and Extension

The number of single adult households has increased over the previous decades, and few health education interventions address these unique living situations, which come with various economic challenges. The Cooking for One curriculum is a cooking-based intervention designed to improve nutrition, food safety, food resource management, and physical activity (PA) behaviors among single adults. This curriculum includes six lessons, each with an educational and hands-on cooking component. Participants included 1,546 adults recruited through Supplemental Nutrition Assistance Education programs in the state of Michigan. Each of the participants underwent the six-lesson Cooking for One curriculum. Prior to and following the intervention, …

Foundational Phases For Community Development: A Model For Enhancing Cooperative Extension’S Role Within The Community, George Grant, Kristina Hains

Journal of Human Sciences and Extension

The Cooperative Extension System (CES) plays a vital role in community education and development across the United States. The objective of this article is to demonstrate the historical and present-day significance of the CES as a catalyst for community development practice, while overlaying a community development model applicable to CES. A literature review is provided on the historical origins, organizational structure, and leadership responsibilities of agents and specialists relevant to community development research and practice. The researchers suggest a novel conceptual model, the Foundational Phases for Community Development, to assist agents and specialists across all areas of programming for engaging …

Bridging The Communication Gap In Natural Disaster Information: An Exploratory Study Of Extension Service Websites, Emmanuel Chisom Okolo, Rafael Landaverde, Laxmi Prasanna Kandi, Kim E. Dooley, Sarah Mccord, Kelsi Opat, Abdul Saboor Rahmany

Journal of Human Sciences and Extension

Natural disasters are expected to become more frequent and severe, increasing the need for effective disaster management. Governments are emphasizing community awareness and local self-reliance, with the Cooperative Extension Services (CES) playing a vital role in distributing science-based knowledge and supporting preparedness efforts. This qualitative content analysis (QCA), guided by Framing Theory, examined how CES disseminated weather-related disaster preparedness and response information from 2003 to 2023 on Extension Service websites. We explored: (1) the frequency of information on natural disaster preparedness and response published on Extension Service websites, (2) dissemination methods, and (3) the quality of disaster preparedness and response …

Full Issue, Volume 13, Number 3, Donna J. Peterson Dr., Scott Cummings, Elizabeth Gregory North

Journal of Human Sciences and Extension

No abstract provided.

Evaluating The Effectiveness Of An Air Purification System In Reducing Bacterial Chondronecrosis With Osteomyelitis Lameness In Broiler Chickens, Abdulaziz Ali Alqahtani

Graduate Theses and Dissertations

Bacterial chondronecrosis with osteomyelitis (BCO) is the primary cause of lameness in commercial broiler production and has a profound impact on animal welfare and cost-effectiveness. The purpose of this experiment was to examine the effect of an air purification system on mitigating BCO lameness in broiler chickens. One thousand eight hundred broiler chicks were reared in two side-by-side research barns. Eight air filtration units were installed in one building, and none in the other. Treatment groups in both houses included positive control birds on wire flooring to induce BCO, as well as negative control, feed additive, vaccination, and a combination …

Prediction Equations For In Vitro Nutrient Utilization Of Bakery Byproducts For Pigs, Junghyun Oh, Hansol Kim, Yoon Soo Song, Noa Park, Youl-Chang Baek, Chung Hyun Kim, Beob Gyun Kim

The Philippine Agricultural Scientist

This study aimed to develop equations for predicting the in vitro ileal disappearance (IVID) of dry matter (DM) and crude protein (CP) and in vitro total tract disappearance (IVTTD) of DM and organic matter (OM) in bakery byproducts based on their chemical composition, including neutral detergent fiber (NDF). Ten sources of bakery byproducts were tested for IVID and IVTTD of nutrients using a 2-step procedure simulating the digestion and absorption in the stomach and small intestine and a 3-step procedure simulating the digestion and absorption in the stomach, small intestine, and large intestine of pigs. The prediction models for IVID …

Antioxidant Enzymes And Osmolyte Accumulation In Okra Cultivars Under Drought Stress, Jawad Ali, Ibadullah Jan, Hidayat Ullah, Muhammad Adnan, Shah Fahad, Hassan Alsberi, Khulud Albalawi, Hakki Akdeniz, Manzoor Ahmmad, Beena Saeed, Noor Us Sabah, Mian Sayed Khan, Abdul Basir, Muhammad Romman, Ayman El Sabagh

The Philippine Agricultural Scientist

Drought stress brought about by worsening environmental conditions due to climate change has increasingly damaging effects on crop production systems. To mitigate these effects, several physiological and biochemical aspects of plants could be used as markers in breeding for the selection of drought-resistant cultivars. Therefore, this study aimed to evaluate the performance of 8 okra cultivars (Arka Anamika, Punjab Selection, Posaswami, Tulsi, Subz Pari, Super Green, Local Multani, and Green Star) under well-watered (control), mild drought stress, and severe drought stress conditions by irrigating plants at an interval of 3, 6, and 9 d after 30 d of planting. Results …

Comparative Effects Of Organic-Based Seed Treatments On Seed Viability And Vigor Of Rice (Oryza Sativa L.) Varieties, Cielo Luz C. Mondejar

The Philippine Agricultural Scientist

Access to high-quality rice seeds remains limited for small and marginal farmers due to high costs, while traditional rice varieties favored by many farmers often suffer from poor seed viability. Seed treatment presents a practical and low-cost approach to enhance seed performance. This study conducted 2 independent experiments to evaluate the effectiveness of 3 organic-based seed treatments: vermitea, a Trichoderma solution, and a water hyacinth decoction. In the first experiment, seeds from 4 traditional rice varieties (Redrice, Dinorado, Calatrava, and Arabon) were treated with distilled water (control) and 75% dilute solutions of each treatment. The second experiment involved different seed …

Assessing Male Asian Corn Borer, Ostrinia Furnacalis (Guenée) (Lepidoptera: Crambidae), Mating Frequency Via Spermatophore Quantification, Gelyn D. Sapin, Marcela M. Navasero

The Philippine Agricultural Scientist

The Asian corn borer (ACB), Ostrinia furnacalis (Guenée), has caused significant yield losses to corn due to its destructive feeding. Bt corn currently controls ACB, but it still poses a threat to Philippine traditional varieties. Random mating of ACB is essential to the insect resistance management (IRM) of Bt corn, and studying the mating behavior, specifically the mating frequency of ACB, is a critical part of understanding the IRM in the Philippines. Currently, there is no available information on the mating frequency of ACB. Here, the male and female ACB were allowed to mate at a ratio of 1 male …

Oviposition Preference Of The Asian Corn Borer, Ostrinia Furnacalis (Guenée) (Lepidoptera: Crambidae), Towards Bt And Non-Bt Corn, And Under Confined Conditions, Merdelyn T. Caasi-Lit, Jessica B. Baroga-Barbecho, John David C. Cortez, Edwin A. Benigno

The Philippine Agricultural Scientist

Several experiments were conducted on the ovipositional preference and behavior of the Asian corn borer (ACB), Ostrinia furnacalis (Guenée). Confirmatory tests were conducted in table cages (1.5 m²) to determine if the results would align with those obtained from experiments on semi-field (285 m²) and mini-screen cage (90 m²) spatial scales. Preference for Bt and non-Bt corn was then observed under confined conditions. Table cage test results showed similar oviposition behavior to that observed in prior studies on larger test areas. There is no preference for either Bt or non-Bt corn plants. ACB adults …

Adult Dispersal Of Field-Released Asian Corn Borer, Ostrinia Furnacalis (Guenée) (Lepidoptera: Crambidae), In Northern And Southern Philippines, Mario V. Navasero, Randolph N. Candano, Gelyn D. Sapin, Wilson N. De Panis

The Philippine Agricultural Scientist

The effectiveness of Bt corn in controlling the Asian Corn Borer (ACB), Ostrinia furnacalis Guenée, is well recognized. However, concerns persist regarding the potential development of resistance to Bt toxins by this pest. This resistance could arise from surviving ACB individuals carrying homozygous resistance alleles, potentially leading to resistant offspring if mating between resistant individuals is not prevented or minimized. To address this issue, various studies have investigated the factors that limit or facilitate resistance development. These factors include adult dispersal and mating behavior in the field, as well as ecological conditions such as weather and landscape features. However, there …