93887 research outputs found
Sort by
Evaluating Different Soil Health Parameters for Edge-of-Field Water Quality
No full textSoil health indicators are increasingly used to guide conservation practice outcomes, but their vertical distribution and relationship to nutrient losses in surface runoff remain understudied. Since 2016, we have conducted multi-depth soil health assessments across agricultural fields in the Great Lakes Basin transitioning to conservation practices such as cover cropping and no-till. Our goal was to identify soil metrics that are predictive of edge-of-field (EOF) water quality outcomes. We assessed 21 biological, chemical, and physical soil indicators at 0–5 cm and 5–15 cm depths, calculating stratification ratios (SR = 0–5 cm ÷ 5–15 cm) for 57 site-years. Nine indicators met the SR \u3e 2 threshold in at least one-third of site-years. Water Extractable Phosphorus (WEP) showed the most frequent stratification (~60%), especially at long-term no-till sites. Other frequently stratified variables included Bray P and β-glucosidase. Indicators like POXC and NAG rarely showed strong stratification. To evaluate the predictive value of these metrics, we trained Random Forest models using soil data (0–15 cm) to estimate EOF total phosphorus (TP) concentration and yield. WEP emerged as the most important predictor for both outcomes, followed by pH and water extractable organic carbon. Sites in early transition (e.g., WI-SW2) showed increasing WEP stratification over time, while others showed declining or stable trends depending on tillage history. Our results highlight the importance of surface-layer monitoring to capture nutrient dynamics linked to runoff risk. Stratified sampling, particularly of WEP at 0–5 cm, is essential for understanding and managing P loss
Evaluation of commercial soil probes (Teralytic NPK) performance in field conditions
No full textNitrogen (N) losses in agricultural systems of the U.S. Midwest represent a significant environmental and economic challenge for farmers, as they pose risks to both water and air quality. However, only a small proportion of farmers adopt cover crops, such as clover and cereal rye, which have proven effective in mitigating N losses. One of the most critical characteristics of N is its high solubility in water and its low retention in soil. Therefore, new technologies have been developed to remotely and continuously monitor soil nutrients in real time. The objectives of this study were to evaluate the performance of commercial soil probes (Teralytic) under field conditions. Performance was assessed with respect to soil moisture, temperature, and nitrate (NO₃⁻). Differences were analyzed between sensor-derived data (predicted) and laboratory measurements (observed) obtained with the SEAL Analytical system for determining soil NO₃⁻. Time-series analyses revealed consistent seasonal patterns, although discrepancies were evident at specific periods. Regression analysis (R² values) indicated acceptable levels of association between predicted and observed data; however, Bland–Altman analysis provided a more robust evaluation of agreement, identifying a slight underestimation of NO₃⁻ by sensors compared to laboratory reference. Furthermore, Bland-Altman plots for both nitrate and soil moisture highlighted systematic biases, with a consistent underestimation of soil moisture by the probes
Technological and digital transfer within the work and professional experience courses at EARTH University
No full textThis study presents the technology and digital skills transfer model implemented by the Geomatics and Remote Sensing Center (GRSC) at EARTH University through its work and professional experience courses. The main objective was to strengthen students\u27 technical capacities by integrating drone-based workflows into precision agriculture practices.
The training followed a “learning by doing” methodology and was structured into four modules: (1) theoretical foundations and manual drone piloting; (2) photogrammetry using drones (Mini 3 Pro, Phantom 4) and processing software such as Agisoft Metashape; (3) digital map generation and analysis with QGIS to support decision-making; and (4) automated precision spraying using the Agras T16 drone equipped with RTK in a banana crop case study.
In 2025, the program directly benefited 100 students from 26 countries. Results show significant global outreach, with Central America representing 52.48% of participants. Additionally, the program demonstrated a strong commitment to gender equity, with 42.5% female participation. This high level of diversity highlights the GRSC’s effectiveness in promoting the adoption of precision agriculture technologies and supporting the sustainable transformation of agricultural systems in tropical regions
Development of High-Durability Manufactured Sand Concrete for Salt Freeze–Thaw Environments
No full textThe Beijing–Taipei Expressway (Jing-Tai Expressway) of China reconstruction and expansion project (Qihe–Jinan section) features a 12-lane dual carriageway with high traffic volume. To ensure safe winter operation, deicing salt is heavily applied, necessitating enhanced salt freeze–thaw resistance of roadside crash barriers. In this project, manufactured sand was used as the fine aggregate in structural concrete. A systematic investigation was conducted to evaluate the effects of stone powder content, air content, air-void spacing factor, and aggregate properties on concrete performance, including salt freeze–thaw resistance, rapid freeze–thaw durability, and compressive strength. The results revealed that non-air-entrained manufactured sand concrete exhibited extremely poor salt freeze–thaw resistance, with cumulative scaling exceeding 4000 g/m² after 28 cycles. The introduction of high-quality air voids (air content controlled between 4% and 6%) significantly improved both freeze–thaw and salt scaling resistance, reducing the scaling mass to 200–550 g/m² after just 8 salt freeze–thaw cycles. Under air-entrained conditions, stone powder contents up to 15% showed minimal negative impact on salt freeze–thaw performance. However, aggregates with high water absorption significantly increased scaling severity. By optimising aggregate selection, controlling air content, and limiting stone powder dosage, the developed high-durability manufactured sand concrete for crash barriers was successfully applied in this project and is now being promoted for broader use in other infrastructure applications
Multiscale Decoupling Analysis of Concrete Durability and Interfacial Micromechanics Using AFM-QNM
No full textTo address the coupled effects of cementitious materials, aggregates, and air content on the salt freeze–thaw resistance of concrete, this study proposes a multiscale decoupling analysis method that integrates macroscopic performance testing with nanoscale mechanical characterization. Concrete specimens were prepared using various binder systems (ordinary Portland cement and slag/fly ash-blended systems), aggregate types (granite and limestone), and target air contents ranging from 3% to 6%. Salt freeze–thaw tests were conducted in a 5% NaCl solution, accompanied by permeability testing, freeze–thaw durability evaluation, and air-void spacing factor measurements. Salt freeze–thaw damage was quantitatively assessed based on mass loss and relative dynamic modulus reduction. In addition, the PeakForce QNM mode of atomic force microscopy (AFM) was employed to characterize the micromorphology and nanoscale mechanical properties of the interfacial transition zone (ITZ), focusing on the spatial distribution of Young’s modulus. The results demonstrate that fly ash-based binder systems significantly increase the Young’s modulus of the ITZ, indicating improved interfacial mechanical performance. In contrast, the use of granite aggregate leads to higher ITZ porosity and weaker interfacial bonding, negatively impacting durability. Concrete with an air content of approximately 4.5% exhibited the best resistance to both conventional and salt freeze–thaw cycling, highlighting the critical role of optimized air entrainment in durability design
Applied Research in Field Crop Pathology for Indiana, 2024
No full textApplied Research in Field Crop Pathology for Indiana, 2024 serves as a summary of the applied field crop pathology research trials conducted in 2024 under the direction of the Purdue Field Crop Pathology program in the Department of Botany and Plant Pathology at Purdue University. In Indiana, there are more than 57,600 farms, 16,000 crop producers, and 900 certified crop advisers, Extension educators, and crop-protection industry representatives who manage more than 11.4 million crop-production acres with a total value of 400 million, making disease identification and management a primary concern. The goal of this book is to share some of the most current, nonbiased, research-based information to address the management of field crop diseases. This data will support individuals engaged in crop production, helping them select effective, sustainable, and economically sound disease-management practices to implement on their farms.https://docs.lib.purdue.edu/purduepress_ebooks/1085/thumbnail.jp
Guardrail Design and Placement 101
No full textNot all “guardrail” is created equal. Within the last 10 years INDOT has adopted the MASH-compliant Midwest Guardrail System (MGS). While similar to the previous standard w-beam guardrail, there are nuances that aren’t well understood by designers. The presentation would reinforce the fundamentals of guardrail as a safety barrier, explain the function of various components of a guardrail system, and review important design considerations
If You Don’t Know, Now You Know: JASE Special Issue on Hip-Hop Pedagogy for Students with Disabilities (Side A)
No full textThis special issue examines Hip-Hop pedagogy (HHP) as a culturally grounded, multimodal approach that supports K–12 students with disabilities. Hip-Hop is presented as a comprehensive culture rooted in the five elements—MCing, DJing, breakdance, graffiti, and knowledge—which offer inclusive pathways for identity development, community, and learning. This special issue of JASE highlights HHP as an asset-based framework that enhances engagement, self-expression, assessment, and social-emotional growth while aligning with high-leverage practices. Research demonstrates that hip-hop–infused instruction can deepen academic understanding, reframe behavioral challenges, and promote equitable, disability-affirming learning environments. The included articles explore belonging for students who stutter, integrated pedagogical models, mentorship through Hip-Hop, mathematics problem solving, and transition planning for postsecondary readiness. Together, these works position Hip-Hop culture as a transformative educational tool that fosters participation, critical consciousness, and authentic inclusion for learners with disabilities
Hip-Hop Culture as a Catalyst for Belonging Among Black Male High School Students Who Stutter
No full textThis ethnographic study explores how Hip-Hop culture fosters belonging, identity, and agency among six Black male high school students who stutter in a public charter school in Baltimore, Maryland. Grounded in culturally sustaining pedagogy, DisCrit, and Hip-Hop pedagogy, the research draws on participant observation, interviews, and field notes to examine how students use freestyling, beat-making, and cyphering as expressive tools. Findings reveal that Hip-Hop repositions stuttering as rhythmic expression, cultivates emotional safety through peer collaboration, and challenges deficit-based speech norms. Participants described Hip-Hop spaces as sites of affirmation where their voices were valued and their identities celebrated. The study calls for inclusive education models that integrate culturally relevant practices and reimagine speech difference through affirming, student-centered frameworks. Implications are offered for educators, speech-language pathologists, and school leaders committed to equity and authentic belonging
Implications of Noninvasive Blood Pressure Pumps on Mean Arterial Pressure
No full textNoninvasive blood pressure pumps are recommended as the primary form of acquiring patient blood pressure to test for blood poisoning. The Philips IntelliVue Patient Monitor MP5, the Philips SureSigns VS4/VS3 Vital Signs Monitor, the Philips EarlyVue VS30 Vital Signs Monitor, the Philips IntelliVue Patent Monitor MP2/X2, the Philips IntelliVue Patent Monitor MMS, and the Philips IntelliVue Patent Monitor MP3/X3 were tested for accuracy. The control condition for hypotension was 95/55 (68) mmHg, normal blood pressure was 120/80 (93) mmHg, and hypertension was 155/85 (108) mmHg. The order of values is arrayed according to diastolic, systolic, and mean arterial pressure. The results displayed no observable difference between error or uncertainty. The average relative uncertainty values were identical for calibrated and uncalibrated devices. These values included 0.32%, 0.38%, and 0.51% for hypotension, normal blood pressure, and hypertension respectively. This result is significantly smaller than the blood pressure values. Also, devices with the greatest deviation in variance were the Philips IntelliVue Patient Monitor MP5 and X2, which exhibited the maximum standard deviation in seven out of the nine cases. The device with the smallest deviation in variance was the Philips IntelliVue Patient Monitor VS3/4 with a minimum variance of zero. Further experimentation is encouraged to collect a larger sample size to complete hypothesis testing and compare it to the industrial quality control of Philips