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Educational approaches in structural engineering have focused on classical methods for solving problems with manual calculations through assignments, quizzes, and exams. The use of computational software to apply the learned knowledge has been ignored for decades. This paper describes an educational approach to tackle the lack of applicable practical exercises in the structural engineering class "CE 506-Prestressed Concrete" at a university in the western United States during the spring of 2017. The class was designed to provide students with the theoretical concepts of prestressed concrete and the ability to interpret applicable design codes. In their project, students continued to build this knowledge by designing a prestressed bridge superstructure according to a unique state design manual. Students prepared a literature review of their selected state in the U.S.A. and used commercial software to perform an analysis and design of their bridge. Additionally, students were asked to backcheck their design using theoretical methods through manual calculations. By the end of the class, students presented their projects in a head-to-head presentation format, to contrast the differences between their designs in a competitive style. This paper summarizes the class structure, the outcome of the design project, and recommendations for future applications of computer technology in structural engineering education.

Alfalfa (Medicago sativa), being a leguminous, highly fibrous and proteinaceous plant, has always been one of the top choices for forage production, but has high cost of irrigation in many dry and warm areas such as California and Arizona. Thus, a reduction of irrigation by using the higher water use efficiency (WUE) varieties can help the growers in reducing the cost and is critical for sustainable agriculture production. WUE is closely related to water loss through transpiring stomata. Alfalfa exhibits high density of stomata on both abaxial and adaxial surfaces. The objective of this study is to examine whether WUE can be improved by manipulating stomatal density in alfalfa. We hypothesize that there is a variation in stomatal density among alfalfa genotypes which may be genetically controlled by the genes as in Arabidopsis. After examining stomatal density in 11 different alfalfa genotypes, we indeed found that variations in stomatal densities among genotypes exist. Our next step is to examine the effect of stomatal density on WUE among selected genotypes varying in stomatal density. Finally, we will examine whether expression of several candidate genes is correlated with stomatal density in alfalfa. Ultimately our goal is to optimize stomatal density in alfalfa to improve WUE without reduction of biomass production. [ABSTRACT FROM AUTHOR]

Climate change continues to increase the frequency, intensity, and duration of heat events and wildfires, both of which are associated with adverse pregnancy outcomes. Few studies simultaneously evaluated exposures to these increasingly common exposures. We investigated the relationship between exposure to heat and wildfire smoke and preterm birth (PTB). In this time-stratified case-crossover study, participants consisted of 85,806 California singleton PTBs (20–36 gestational weeks) from May through October of 2015–2019. Birthing parent ZIP codes were linked to high-resolution daily weather, PM 2.5 from wildfire smoke, and ambient air pollution data. Heat day was defined as a day with apparent temperature >98th percentile within each ZIP code and heat wave was defined as ≥2 consecutive heat days. Wildfire-smoke day was defined as a day with any exposure to wildfire-smoke PM 2.5. Conditional logistic regression was used to calculate the odds ratio (OR) and 95% confidence intervals (CI) comparing exposures during a hazard period (lags 0–6) compared to control periods. Analyses were adjusted for relative humidity, fine particles, and ozone. Wildfire-smoke days were associated with 3.0% increased odds of PTB (OR lag0 : 1.03, CI: 1.00–1.05). Compared with white participants, associations appeared stronger among Black, Hispanic, Asian, and American Indians/Alaskan Native participants. Heatwave days (OR lag2 : 1.07, CI: 1.02–1.13) were positively associated with PTB, with stronger associations among those simultaneously exposed to wildfire smoke days (OR lag2 : 1.19, CI: 1.11–1.27). Similar findings were observed for heat days and when other temperature metrics (e.g., maximum, minimum) were used. Heat and wildfire increased PTB risk with evidence of synergism. As the occurrence and co-occurrence of these events increase, exposure reduction among pregnant people is critical, especially among racial/ethnic minorities. • Wildfire exposure is associated with higher risks of preterm birth. • Unusually hot days and heatwaves are also associated with preterm birth risks. • Co-exposures of heat and wildfires have compounding effects. • Communities of color are more susceptible to these exposures. • The crossover nature of this study controls for time-invariant confounding. [ABSTRACT FROM AUTHOR]