School breakfast and body mass index: a longitudinal observational study of middle school students.

OBJECTIVES: The objectives are to identify breakfast location patterns (frequency and place of breakfast consumption) and explore the association between breakfast patterns and weight status over time among preadolescents. METHODS: Surveys and physical measurements were completed among students from 12 randomly selected schools in a medium-sized urban school district. All students were followed from fifth (Fall, 2011) to seventh grade (Fall, 2013). Latent transition analysis and longitudinal analyses were used in the study. RESULTS: Six distinct breakfast location patterns emerged at baseline (1) frequent skippers; (2) inconsistent school eaters; (3) inconsistent home eaters; (4) regular home eaters; (5) regular school eaters and (6) double breakfast eaters. Results from the longitudinal analyses revealed that there was an increased odds of overweight/obesity among frequent skippers compared with double breakfast eaters after adjusting for school, year and students' race/ethnicity (AOR: 2.66, 95% CI: 1.67, 4.24). Weight changes from year to year were similar between double breakfast eaters and other students. CONCLUSIONS: Concerns that a second breakfast at school increases risk of excessive weight gain are unsupported. Students who regularly consumed breakfasts at school, including double breakfast eaters, were more likely to exhibit a healthy weight trajectory. Additional research is needed to understand the impact of universal school breakfast on students' overall diets.

Wheat response to differences in water and nutritional status between zeoponic and hydroponic growth systems.

Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L. cv. USU-Apogee). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15 to 20 L m-2 d-1 up to Day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences in water status were noted between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT than in hydroponic culture. Sterile green tillers made up 12 and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4-N nutrition of plants grown in ZPT compared with NO3-N in hydroponic nutrient solution. It is probable that NH4-N-induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS.