Mapping sub-field maize yields in Nebraska,USA by combining remote sensing imagery,crop simulation models,and machine learning

Precision Agriculture - Crop yield maps are valuable for many applications in precision agriculture, but are often inaccessible to growers and researchers wishing to better understand yield...     

Activity of the rhizosphere of perennial leguminous grasses under conditions of biological agriculture

Versatile microbe-plant interrelations are shown in investigations performed on gray forest soils with the use of perennial leguminous grasses of various growth years. The main parameters of biological activity and agrochemical indices are assessed and the structure of the microbial assemblage of rhizosphere soils is determined. Cultivation of perennial leguminous grasses in a biological agriculture system creating optimal conditions for growing subsequent farm crops is examined.     

Validity and reliability of a calcium checklist in early elementary-school children

OBJECTIVE: To create, validate and assess the reliability of a checklist to measure calcium intake in children. DESIGN: Calcium intakes from a checklist and parent-assisted 24-h dietary recall were compared. Checklist reliability was assessed separately. SETTING: After-school programmes in the United States. SUBJECTS: Forty-two children (18 males, 24 females, age = 8.0 +/- 0.9 years) participated in the validation analysis and 49 children (28 males, 21 females, age = 7.5 +/- 0.9 years) in the reliability analysis. RESULTS: No differences in mean calcium intakes were found by method or gender. The checklist correlated well with recall among girls (r = 0.65, P = 0.01) but not boys (r = -0.33, P = 0.19). Agreement over time was above 80% for most foods. CONCLUSION: The calcium checklist is useful for assessing calcium intake among groups of 6-10-year-old children in settings that preclude parental assistance. More research is needed to improve accuracy among boys.