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Native Americans domesticated maize (Zea mays ssp. mays) from lowland teosinte parviglumis (Zea mays ssp. parviglumis) in the warm Mexican southwest and brought it to the highlands of Mexico and South America where it was exposed to lower temperatures that imposed strong selection on flowering time. Phospholipids are important metabolites in plant responses to low-temperature and phosphorus availability and have been suggested to influence flowering time. Here, we combined linkage mapping with genome scans to identify High PhosphatidylCholine 1 (HPC1), a gene that encodes a phospholipase A1 enzyme, as a major driver of phospholipid variation in highland maize. Common garden experiments demonstrated strong genotype-by-environment interactions associated with variation at HPC1, with the highland HPC1 allele leading to higher fitness in highlands, possibly by hastening flowering. The highland maize HPC1 variant resulted in impaired function of the encoded protein due to a polymorphism in a highly conserved sequence. A meta-analysis across HPC1 orthologs indicated a strong association between the identity of the amino acid at this position and optimal growth in prokaryotes. Mutagenesis of HPC1 via genome editing validated its role in regulating phospholipid metabolism. Finally, we showed that the highland HPC1 allele entered cultivated maize by introgression from the wild highland teosinte Zea mays ssp. mexicana and has been maintained in maize breeding lines from the Northern United States, Canada, and Europe. Thus, HPC1 introgressed from teosinte mexicana underlies a large metabolic QTL that modulates phosphatidylcholine levels and has an adaptive effect at least in part via induction of early flowering time.

Allelopathy plays crucial roles in invasive plant viability and agricultural production systems. However, there is no well-established hands-on learning activity to teach the concept of allelopathy. Nor is there an activity which allows students to gain knowledge about glucosinolates and their corresponding enzyme, myrosinase, which are present in almost all "Brassica" crops. Lettuce germination was counted by the students from three different treatments including water treated with Parafilm sealing, horseradish treated with Parafilm sealing, and horseradish treated without Parafilm sealing. Additionally, lettuce root length was measured by students using ImageJ software from each treatment using pictures captured by students' smartphones. Students took an identical quiz as a pre-laboratory and a post-laboratory assignment. Their average scores on the pre-laboratory and post-laboratory quizzes were 3.14 and 6.56 out of 10, respectively, indicating the lab activity significantly improved students' understanding of allelopathy and glucosinolate-myrosinase system. In addition, students (n = 76) completed a survey post-laboratory to assess their self-efficacy. This simple and cost-effective laboratory activity improved students' knowledge and skill development as it made learning more inviting, meaningful, and fun.

We report here the development of an inexpensive and engaging laboratory-based activity that can help students learn about the scientific method and the role of plant epicuticular waxes and surfactant function on waxy plant leaves as real life example in the agricultural industry. Three each of nontreated collard leaves ("Brassica oleraceae" L. Acephala group) and brushed-leaves were sprayed with water to demonstrate hydrophobicity of epicuticular waxes. Another set of three nontreated collard leaves was sprayed with Tween 20 containing water to demonstrate function of surfactant. Then, water retention rate was calculated by subtracting between before and after spray treatments. Water contact angles were measured by ImageJ software from nontreated and brushed-leaves from pictures taken by students' smartphones. This lab activity provides a foundation for instruction on the importance of the plant epicuticular waxes that is the outermost hydrophobic barrier in agrochemical applications and the function of surfactant on waxy leaf surface.

Background and Aim: Transnasal endoscopy (TNE) has been proven to reduce the need for intravenous anesthesia and the cost of the exams compared to conventional esophagogastroduodenoscopy (EGD) in adults. The objective of this study is to evaluate the benefits and the adverse effects of TNE in adolescents compared to conventional EGD., Methods: We reviewed the pediatric patients from 2012 to 2022, who had undergone TNE at National Taiwan University Hospital due to epigastralgia. Age and gender-matched controls, who had undergone conventional EGD for epigastralgia at the same time, were also recruited., Results: Totally 15 patients, aged between 12 and 20 years old, who had undergone TNE for epigastralgia at National Taiwan University Hospital were recruited as the study group. Another 60 age and gender-matched adolescents were also recruited in the control group. The needs of conscious sedation (9.3% vs 58.3%), hospitalization rate (13.3% vs 43.3%), the mean exam time (7.34 vs 9.96 min), and the cost of endoscopy (57.6 vs 93.2 USD) were significantly lower in the group of TNE as compared with the conventional EGD group. There was no difference in the percentage of complications, including dizziness, epistaxis, nausea, and vomiting, after procedures (P > 0.05.) CONCLUSIONS: TNE is a cost-effective exam and it also reduces the exposure to conscious sedation, the need for hospitalization and the exam time, making it a good choice for adolescents who are scheduled to undergo EGD for epigastralgia., (Copyright © 2024 Formosan Medical Association. Published by Elsevier B.V. All rights reserved.)