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La Nuit des Idées: Building Solidarity across Difference
No full textJoin us for a concert-conversation with Cajun standards mixed up with a bit of folk, swamp pop, and country.
The evening will be facilitated by LGBTQ+ Cajun musicians Gina Forsyth (the Mid-City Aces, the Bruce Daigrepont Band), guitarist Jan Boney, accordionist Rosemary Benoit (Lee Benoit & the Bayou Stompers, Louisiana Cajun Mixers), bassist Sam Wróbel (the 99 Playboys) and drummer Maegen Benoit (Lee Benoit Family Band)
Evaluation of Soybean Response to Sulfur Fertilizer Rates and Sources
Get PDFSulfur (S) deficiency has become a significant concern for producers due to over 90% reduction in atmospheric-S deposition since the “Clean Air Act” was established. Soil organic matter, another key source of S, is steadily declining due to continuous tillage. So, we evaluated soybean [Glycine max (L.) Merr.] yield and leaf-S concentration responses to six fertilizer-S rates (0, 11, 22, 34, 45, and 67 kg S ha⁻¹) across 50 site-years, and six fertilizer-S sources (no-S check, Ammonium Sulfate (AMS), Sul4r-Plus/Gypsum, K-Mag, Tiger90CR, and Poly4) across 9 site-years in Louisiana from 2023-2024. In S rate study, soybean yield responded positively to fertilizer-S at 11 out of 50 sites. Mehlich-3 soil-test S (STS) concentration at 0-15 cm depth correlated better with relative soybean yield, explaining 46% of the yield variability, compared to 41% at 0-30 cm depth. Critical STS concentrations were 9-11 mg kg⁻¹ at 0-15 cm and 7-9 mg kg⁻¹ at 0-30 cm depths, with 86% and 100% accuracy, respectively, in identifying S-deficient sites. Critical STS at 0-30 cm depth resulted in more errors (8%) in predicting S-sufficient sites than 0-15 cm depth (6%). Leaflet-S concentration at full-flowering (R2-3) stage explained 38% of the relative yield variation, with a critical concentration of 2.65-3.00 g kg⁻¹. Sites having concentration below this range also has STS concentrations either below or within the critical level at 0-15 cm depth. In S source study, positive yield responses were measured at 2 out of 9 sites. At both responsive sites, Tiger90CR consistently increased yields compared to no-S check when applied before planting only. Gypsum and K-Mag also consistently increased yields when applied at full-flowering (R2-3) stage, with the potential for similar results if applied at or before planting. Overall, positive yield responses were observed in both fertilizer-S rate and source studies when STS and leaflet-S concentrations were below or near the critical ranges. Based on our data, a 22 kg S ha-1 is recommended when STS concentrations are below or near the critical limit at the 0-15 cm depth. Limited site responses made it difficult to recommend a specific fertilizer-S source, and further research is warranted
Comparing Methods of Evaluating Sensitivity to Common Reinforcement Contingencies and Bias Toward Appropriate Versus Challenging Behavior
No full textRecent research has demonstrated the utility of recording (Fahmie et al., 2020) and reinforcing (Deshais et al., 2024) appropriate as well as challenging behavior during a functional analysis. Two bias and sensitivity evaluations (BASE) were compared, one that equated the contingencies for appropriate and problem behavior and another that favored problem behavior as in more traditional functional analyses. Six neurotypical children were recruited and behavior was recorded on a neutral to severe behavior scale. We evaluated sensitivity and bias for each participant in an individual and summary analysis. Results showed that participants displayed a bias towards challenging behavior across BASE types, with the Equal BASE revealing more instances of sensitivity to reinforcement and the Suboptimal BASE capturing more instances of severe challenging behavior. Findings suggest that the Equal BASE may help identify risk factors for challenging behavior and inform preventive strategies
Beyond Water Surface Profiles: A New Iterative Methodology for 2D Model Calibration in Rivers Using Velocity Data from Multiple Cross-Sections
Get PDFObserved longitudinal water-surface profiles are commonly used to calibrate river hydrodynamic models, relying on assumptions of lateral uniformity in water surface elevation and velocity distribution. While suitable for 1D models, this approach has limitations in regard to 2D model calibration. When 2D flow measurements are available, a more robust quantitative evaluation is necessary to assess model accuracy. This study introduces a novel methodology to improve 2D model calibration and evaluate performance. High-resolution bathymetric and hydrodynamic data collected with a multibeam echosounder (MBES) and acoustic Doppler current profiler (ADCP) were aligned to compare observed and simulated flow velocities at matching spatial locations. Statistical metrics, including relative mean absolute error and root-mean-square error, were employed to assess hydrodynamic modeling. The methodology was tested using MBES and ADCP measurements alongside TELEMAC-2D simulations of a dynamic neck cutoff on the White River, Arkansas, USA. This approach provides a 2D calibration process, enhancing model accuracy and informing parameter selection, such as channel boundary roughness and downstream boundary water surface elevation
A big data approach to mitigating the MAUP in measuring excess commuting
Get PDFExcess commuting, defined as the inefficiency resulting from spatial mismatches between residential and employment locations, poses significant challenges for urban planning and transportation systems. This study uses big data from individual vehicle trips collected in Tampa, Florida, to quantify excess commuting more accurately than traditional zonal approaches. Through the application of Linear Programming (LP) and Integer Linear Programming (ILP) models, this research measures minimum and actual commuting patterns across different spatial scales—census tract, block group, and individual trip levels. The findings reveal a clear scale effect associated with the Modifiable Areal Unit Problem (MAUP), as smaller spatial units consistently yield shorter minimum commuting distances and times and the ILP model at the individual trip level yields the least. By directly analyzing actual trips rather than simulated data, this approach provides a more precise and realistic assessment of excess commuting. The results underscore the values of methodological improvements and individual-level data in refining our understanding of excess commuting and supporting more efficient urban planning and policymaking
Long-Term field testing of the accuracy and HVAC energy savings potential of occupancy presence sensors in A Single-Family home
No full textThe energy-saving potential of occupancy-centric smart thermostats has been extensively explored in simulations but lacked field testing for energy savings quantification and sensor performance assessment in real buildings. This paper presents a long-term field study conducted in a single-family home in Texas, U.S. to evaluate the performance of occupancy-centric controls (OCC) of HVAC (heating, ventilation, and air-conditioning) system in terms of energy savings, sensor accuracy, and impact on electric peak demand. The test site was equipped with a commercial off-the-shelf (COTS) smart thermostat and multiple occupancy presence sensors for OCC implementation. Additionally, a sub-metering system was installed to monitor electricity consumption of various end-use equipment, including the HVAC system. A supplementary device was installed to track the ground-truth occupancy for the accuracy evaluation of the occupancy presence sensor. Scenarios of baseline and OCC controls were alternated weekly over the 20-month testing period. The results indicated an effective OCC execution, as evidenced by indoor temperature profiles. During the 2023 cooling season, OCC achieved total energy savings of 1,958 kWh, corresponding to a 17.6% energy savings ratio. Under certain conditions, daily HVAC energy savings reached as high as 17 kWh, with a savings ratio of 35%. Sensor performance showed an overall accuracy of 83.8%, a False Positive Rate (FPR) of 12.8%, and a False Negative Rate (FNR) of 47.4%. A key limitation was the sensor\u27s inability to detect stationary occupants during sleep, leading to a midnight FNR of nearly 100% and significantly compromising thermal comfort. Additionally, the implementation of OCC resulted in extended periods of high electricity demand on summer afternoons, affecting occupant\u27s thermal comfort and posing potential challenges to community-level grid operations if OCC were widely adopted. This study addresses a critical research gap by empirically investigating energy-saving potential and occupancy sensor performance in residential buildings. Through a comprehensive field-testing study, the research examines the interrelationship between sensor accuracy, energy savings, and thermal comfort, an area that has received limited attention in the current literature
Toward an Understanding of the Transport Routes of Enzyme-responsive, Fluorescent Molecular Probes in 3-Dimensional Tumor Mimics
No full textTo satisfy the requirements of clinicians charged with locating and assessing diseased tissue in the human body via new qualitative and quantitative visualization and imaging modalities that hinge on the successful creation of novel imaging agents, the cellular and tissue transport properties of those entities must permit access to diseased tissue. For imaging approaches employing target-activated fluorescence probe-based readout across a range of emission energies, ready access of probes to diseased tissue depends on their fundamental physicochemical properties in conjunction with those of the biological milieu, which for 3-dimensional tissue mimics can be complex. Here, a set of computational and empirical approaches are described in an effort to gain fundamental knowledge about the transportation of cytosolically activated fluorescence-based molecular probes into cells in 2-dimensional and 3-dimensional mammalian cell cultures, as well as their ability to traverse between cultured cells in 3-dimensions and gain access to the interior of cells, present deep within tissue mimics. While such knowledge is critical for identifying a variety of diseased tissues, the fields of fluorescence-guided surgery (FGS) for cancer imaging and monitoring of disease-linked enzyme activities during disease treatment will be transformed by an understanding of how activatable probes can be designed and synthesized to reach diseased cells present deep within tissue. In this study, I build on successes of the McCarley research lab with small-molecule imaging probes whose energy and intensity of emission are selectively altered by an intracellularly present cancer-marker enzyme activation, namely, 2-electron reduction via human NAD(P)H: quinone oxidoreductase isoenzyme-1 (hNQO1) to yield a reporter variant. The computed physicochemical properties of six probes and reporter variants—with emission spanning the visible and near-infrared—are examined in the context of their transport properties and ultimate organelle fate using two-dimensional cell cultures and three-dimensional, lab-grown multicellular tumor spheroids (MCTSs) of human colorectal adenocarcinoma cells (HT-29). Examination of transport routes in two-dimensional cultured HT-29 cells is achieved with appropriate immunostaining after incubating in appropriate probe/reporter solutions and additional organelle-tracker molecules, followed by inspection with confocal laser scanning and spinning disk confocal microscopy, equipped with super-resolution by optical re-assignment (SoRa) functionality. Information about probe/reporter location in HT-29 MCTSs is obtained performing identical staining experiments in concert with light sheet fluorescence and advanced X resonant or AXR point scanning confocal microscopy
DEVELOPMENT AND APPLICATION OF A NONLINEAR/NONLOCAL IMPLICIT ELECTROLYTE MODEL TO STUDY ELECTROCHEMICAL SYSTEMS USING PLANE WAVE DENSITY FUNCTIONAL THEORY
No full textThis dissertation introduces computational tools to accurately simulate electrocatalytic processes in a realistic electrochemical environment while solving limitations of existing implicit solvation models in plane wave density functional theory. It describes the development and implementation of an implicit electrolyte model in the Vienna Ab initio Simulation Package (VASP) that includes nonlinear dielectric and ionic responses as well as a nonlocal definition of the cavities. The implementation into the existing VASPsol code is numerically efficient and exhibits robust convergence, requiring computational effort only slightly higher than the original linear polarizable continuum model. The nonlinear + nonlocal model is able to reproduce the characteristic “double hump” shape observed experimentally for the differential capacitance of an electrified metal interface while preventing “leakage” of the electrolyte into regions of space too small to contain a single water molecule or solvated ion. The model also gives a reasonable prediction of molecular solvation free energies as well as the self-ionization free energy of water and the absolute electron chemical potential of the standard hydrogen electrode. All of this, combined with the additional ability to run constant potential density functional theory calculations, should enable the routine computation of activation barriers for electrocatalytic processes. Additionally, a hybrid solvation methodology is introduced which enhances accuracy in predicting pKa values and free energies by incorporating explicit water molecules, aligning closely with experimental data. The research further applies these models to analyze the behavior of the Pt(111) surface under varying pH and potentials, constructing a Pourbaix diagram that elucidates the stability of surface states