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UNDERGRADUATE STUDENTS’ EXPERIENCES WITH ASSUMPTIONS OF INFERIORITY IN ENGINEERING GROUP WORK SETTINGS
No full textPeople stereotype women to be less skilled and competent in STEM (science, technology, engineering, and mathematics) than men [Nosek, B. A., Smyth, F. L., Sriram, N., Lindner, N. M., Devos, T., Ayala, A., Bar-Anan, Y., Bergh, R., Cai, H., Gonsalkorale, K., & Kesebir, S. (2009). National differences in gender– science stereotypes predict national sex differences in science and math achievement. Proceedings of the National Academy of Sciences of the United States of America, 106(26), 10593–10597]. These stereotypic beliefs can leak out in words and behaviors as microaggressions—defined as brief everyday verbal, behavioral, or environmental slights directed toward someone due to their social category [Sue, D. W. (2010). Microaggressions in everyday life: Race, gender, and sexual orientation. John Wiley & Sons].—and can be a hindrance to women’s persistence and inclusion in STEM fields. In the current research we utilized a mixed methods approach to document the content and presence of microaggressions in undergraduate engineering group work settings among women and men. In Study 1, focus groups with women and men engineering students (N = 43) revealed that women reported experiencing microaggressions in the form of assumptions of inferiority or behaviors suggesting that they possess inferior STEM skills and competence. In Study 2, we developed a behavioral coding rubric to document the presence of assumptions of inferiority among women and men students (N = 260) in engineering teams as judged by trained independent observers. In Study 2 observations revealed that more women were the target of assumptions of inferiority than men, corroborating self-report findings. Moreover, although our studies focused on gender-based microaggressions, Study 2 observational coding revealed People of Color were the targets of assumptions of inferiority more than White people. Results complement prior self-report data and indicate that diversity and inclusion efforts should focus on reducing the presence of microaggressions in peer STEM contexts
BOARD # 310: WIP: Impact of Prior Programming Experience on Self-Efficacy Impacts of WebTA Autocritiquer
No full textWebTA is an autocritiquer providing real-time feedback for programming in flipped-class active learning classes for first-year engineering students. WebTA was developed to critique student code in introductory computer science courses that programmed using Java. WebTA provides just-in-time feedback on syntax errors, subtle logic errors, and style issues.
The I-USE project Rich, Immediate Critique of Antipatterns (RICA) in Novice Programmer Code: Broadening Adoption, Supporting Student LEarning, and Enhancing Programming Competencies project is simultaneously extending WebTA for MATLAB and examining its impact on the computer programming self-efficacy of novice programmers. Within first-year engineering classes, students were asked to submit MATLAB code to WebTA for feedback, so that they might revise it prior to submission for grading. In this manner, WebTA provided real-time, instantaneous feedback for classes of up to 120 students at a time - a feat which even the most attentive teaching team of instructors and TAs could not achieve.
As self-efficacy is tied to success in engineering programs, and computer programming is an essential component of the education of first-year engineering students, our team is examining the impacts of WebTA on the computer programming self-efficacy of first-year engineering students as they learn to code. This paper summarizes our current progress investigating how prior programming experience and initial confidence levels influence the effectiveness of the code critiquer tool in enhancing programming self-efficacy. By analyzing these variables, the study identifies key factors that mediate the impact of automated feedback and provides strategies for tailoring educational interventions to diverse student needs
Cyber-physical framework for smart paint manufacturing: Hybrid integration of PLC and recipe management simulation
No full textThis study investigates the implementation of Industry 4.0 paradigms in the context of smart paint manufacturing, focusing on process control and recipe management through the integration of Ignition SCADA, a Siemens programmable logic controller (PLC), and a MySQL Workbench database. The developed architecture employs Ignition as an interoperable communication interface that facilitates bidirectional data exchange between the PLC and the database, thereby establishing a cyber-physical system for automated monitoring and control. The digital recipe management module formalizes paint formulations into parameterized datasets specifying paint and solvent ingredient ratios, process variables, and operational constraints, which are executed autonomously by the control system to ensure uniformity, traceability, and adaptive process optimization. The simulation framework replicates real-time production dynamics, addressing variability in raw-material supply and process conditions through data-driven feedback mechanisms. The results demonstrate the feasibility of achieving enhanced process efficiency, product quality, and scalability via the convergence of SCADA, PLC, and database technologies within an Industry 4.0 environment. This work contributes to the advancement of smart manufacturing methodologies and provides a replicable model for digital transformation in process industries
Imaging of dynamic processes in materials with a laser-wakefield accelerator
No full textBetatron x rays generated from laser-wakefield accelerators are a promising source for imaging dynamic processes in materials. Here, we present proof-of-concept imaging of microstructural evolution in a hypermonotectic Al-Bi alloy, which consists of liquid Bi particles in a solid Al matrix. The images capture the elongation and fragmentation of Bi particles upon isothermal annealing. Because of the femtosecond time scale of the betatron source, the images are not subject to motion blur, whereas the accessibility of the source allows for studies of long-term processes such as annealing. The high-resolution data reveal that the evolution of Bi particles is mediated by an interplay of grain-boundary wetting and morphological instability, in stark contrast to an earlier proposal for (inverse) coarsening
Rotifer occupancy and seasonal variation within Frullania eboracensis (Frullaniaceae) lobules
No full textBdelloid rotifers are well documented as inhabitants within lobules of the widely distributed epiphytic liverwort, Frullania eboracensis. This study provides a detailed description of rotifer occupancy within lobules near the shoot tip of F. eboracensis. The objectives of this study were to test whether rotifer density in lobules of F. eboracensis differed among tree species, understand how rotifers are distributed within F. eboracensis, the aggregations of lobule-dwelling rotifers, and how rotifer abundance is impacted by seasonality. The highest densities of rotifers within F. eboracensis lobules occurred on northern red oak (0.67 rotifers/lobule ± 0.069, mean and SE) and aspen (0.66 rotifers/lobule ± 0.046, mean and SE). Shoot tips of F. eboracensis were collected from five different tree species in fall 2014 to fall 2016. Rotifers had a higher probability of occupancy for the first 5-6 lobules, slowly declining thereafter. The probability of occupancy was significantly related to lobule sequence from the shoot tip (p\u3c0.05, 95% CI-0.113 to-0.064) and branching level (p\u3c0.05, 95% CI-0.984 to-0.195). Of all the rotifers counted within lobules, 34% were solitary, 23% were in pairs, 18% in trios, and 17% were in groups of five or more. Rotifer abundance was stable across the 1.5-year period, but there was a slight increase in density during the late fall and early winter. Studies of rotifers in other aquatic habitats emphasize considerable seasonal fluctuations in their populations, but the lack of competitors and limited predation within F. eboracensis lobules contributes to their stability. Anhydrobiosis also lessens the impact of drought and freezing temperatures on rotifer abundance
Exploring the effects of non-Kolmogorov turbulence on intensity statistics via wave optics simulations
No full textWave optics simulations are used to explore the effect of non-Kolmogorov turbulence on intensity statistics. In this context, non-Kolmogorov turbulence is defined as a change in the power-law of the medium away from the traditional -11/3 power spectral density slope used to describe Kolmogorov turbulence. I examine how a change in the power law affects the transition of log irradiance statistics from log normal to a gamma gamma distribution one measure of the transition from weak to moderate or strong turbulence. Non-Kolmogorov turbulence is traditionally described over a range in slope between -3 to -4. I find that for the case where the plane wave Rytov number is 1 in Kolmogorov turbulence, the intensity statistics are roughly matched for the case when the power law is 3.9 when the Rytov is 2. When the power law is -3 the same condition is matched when the Rytov number is 0.5. This work also examines the intensity correlation statistics with power-law and will compare results to existing theory
On the Hamilton-Waterloo Problem with a single factor of 6-cycles
No full textThe uniform Hamilton-Waterloo Problem (HWP) asks for a resolvable (CM, CN)decomposition of Kv into α CM-factors and β CN-factors. We denote a solution to the uniform Hamilton-Waterloo problem by HWP(v, M, N, α, β). Our research concentrates on addressing some of the remaining unresolved cases, which pose a significant challenge to generalize. We place a particular emphasis on instances where the gcd(M, N) = {2, 3}, with a specific focus on the parameter M = 6. We introduce modifications to some known structures, and develop new approaches to resolving these outstanding challenges in the construction of uniform 2-factorizations. This innovative method not only extends the scope of solved cases, but also contributes to a deeper understanding of the complexity involved in solving the Hamilton-Waterloo Problem
“Being Blessed” With a Crisis: Exploring the Rhetoric of Crisis Exploitation in the Mepe Flood in Ghana
No full textA crisis is recognized as a focusing event that brings attention to a particular situation and the actors involved. In young democracies where equitable access to media coverage for opposition politicians and parties is limited, crisis presents a unique rhetorical situation for affected opposition politicians when strategically handled. Using Crisis Exploitation based on Nord and Olsson’s tripartite model as a framework, this paper explores how a member of parliament in Ghana belonging to the opposition party frames the Akosombo and Kpong Hydro-electric dams spillage that affected his constituency using X rather than traditional mass media platforms. Existing literature on crisis communication in Africa focuses on actors who are directly involved or responsible for the crisis and how they can manage information and their reputation. We contend that in young democracies where political obligations are not clearly demarcated, opposition political actors can leverage a crisis to set national agendas, exert their managerial competence, and enhance their image in the public consciousness. Through textual analysis of posts from the MP, the study identifies the parliamentarian’s use of attributional, managerial, and morality frames in the context of social media logic while handling the Mepe flood incident as tools to directly engage state institutions and the incumbent party while promoting his party and himself. This study’s contribution challenges African traditional notions of crisis being a moment of solidarity devoid of partisanship and self-promotion as well as providing additional positionalities from which crisis communication can be explored in Africa
Regio- and Stereoselective Halogenation by an Iron(II)- and 2-Oxoglutarate-Dependent Halogenase in the Biosynthesis of Halogenated Nucleosides
No full textIron(II)- and 2-oxoglutarate-dependent (Fe/2OG) enzymes have garnered strong research interest in past decades due to their ability to catalyze regio- and stereoselective C-H functionalization via a single reactive intermediate, the oxyferryl species. In addition to the hydroxylation reaction that is commonly observed, other reaction outcomes have also been discovered in Fe/2OG enzymes. Among them, halogenation has attracted much research effort with the goal of revealing the molecular determinants to favor halogenation over hydroxylation however, a full mechanistic picture is still missing. In this study, by investigating a recently identified Fe/2OG halogenase, AdeV, from the biosynthetic pathway of Adechlorin, we show, via biochemical, kinetics, and spectroscopic characterizations, that two oxyferryl intermediates are formed during the AdeV reaction in a sequential manner, which interconvert but only one shows kinetic competency to enable C-H activation and leads to the conversion of 2\u27-deoxyadenosine monophosphate (2\u27-dAMP) and 2\u27,3\u27-dideoxyadenosine monophosphate (ddAMP) to 2\u27-Cl-dAMP and 2\u27-Cl-ddAMP, respectively. By applying chemical synthesis and product characterization by detailed NMR analysis, the stereochemical assignment of the AdeV-catalyzed reaction is resolved, whereof the C-H bond cleavage and the C-Cl bond formation occur in a suprafacial manner. Using the experimental observations as a guide, the computational studies reveal that the kinetically competent oxyferryl intermediate structurally exhibits an offline configuration. However, this offline oxyferryl intermediate requires a structural conversion to a metastable inline configuration to perform a regio- and stereospecific C-H activation via a σ reaction channel. The subsequent conversion back to the offline configuration in the hydroxy-ferric state facilitates the final C-Cl bond formation
IRON ORE TAILINGS REPROCESSING BY ELECTROSTATIC SEPARATION PLUS TWO STAGES FROTH FLOTATION
No full textThe reprocessing of tailings is crucial for recovering valuable iron and reducing the environmental impact associated with tailings disposal. This study investigates the practicality of reprocessing tailings to enhance iron oxide content, combining electrostatic separation with a two-stage froth flotation process using oleic acid (direct flotation) and amine (reverse flotation). The primary goal is to efficiently recover valuable iron from tailings, thereby reducing waste and promoting sustainable resource utilization. The process aims to upgrade the iron oxide content to around 93-99% Fe2O3, making the recovered material suitable for the production of direct-reduced iron.
Electrostatic separation was first used to produce a pre-concentrate while rejecting the bulk of the silicate minerals. The pre-concentrate undergoes direct flotation, which successfully enriches the iron oxide content from 25% to 72% Fe2O3. This initial stage serves as a bulk separation process, removing a significant portion of the non-iron-bearing components. Subsequently, a reverse flotation technique is applied to further refine the iron oxide concentrate. The implementation of reverse flotation on the direct flotation product resulted in a substantial increase in iron oxide content, achieving a final grade between 93% and 99% Fe2O3. This two-stage flotation approach, complemented by electrostatic separation, demonstrates a promising pathway for efficient tailings reprocessing and iron recovery, offering both economic and environmental benefits. The findings suggest that this method could be an effective strategy for valorizing tailings and reducing reliance on primary iron ore sources