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151.
Garvey PM Murphy DJ Yoder AM Hilton JW 《Journal of agricultural safety and health》2008,14(3):333-349
Guidelines in the U.S. Department of Labor's Hazardous Occupations Order in Agriculture (AgHO) regulations state that youth can receive tractor safety certification after participating in a 10-hour course, or receive tractor and machinery safety certification after participating in a 20-hour course. An additional four hours of orientation to on-farm hazards and general safety is required to receive full certification in a 24-hour course. Previous research has shown that traditional safety education certification programs were conducted with non-standardized methods and old curriculum materials. The objective of the National Safe Tractor and Machinery Operation Program (NSTMOP) project was to design an effective, efficient, and accountable youth farm machinery certification program with national uniformity and a single set of economically producible instructional materials with demonstrated content validity. The format for the NSTMOP project was guided by focus groups, a national steering committee, and selected agricultural safety educators. Primary curriculum materials include a task sheet format, and new skills and driving evaluations. Data analysis indicates that the instructional materials, the instructional plan, and the evaluation of student participants satisfactorily met the objectives of the NSTMOP project and the AgHO regulations. 相似文献
152.
Hydrogel amendments have been used to improve seedling survival and establishment particularly in dry environments. However, their effect on survival and growth of newly transplanted seedlings under varying water stress conditions is poorly known. In this regard, we examined the effects of Aqua Matrix Forestry~?, a potassium-based water-absorbent polymer, on the survival and early growth of Pinus patula seedlings planted in early-,mid-and late-dry season in the eastern highlands of Zimbabwe. The late-dry season was hotter and received more rainfall than the early-and mid-dry season. Hydrogel increased seedling survival by 34 and 22% in the mid-and late-dry season, respectively. Also, hydrogel-treated seedlings were significantly taller than untreated seedlings(P \ 0.001). The height to root collar diameter ratio of hydrogel-treated seedlings was greater than that of untreated seedlings only in the mid-dry season. In conclusion, increase in survival and early growth of hydrogel-treated seedlings suggests that hydrogels can be used to extend planting beyond the rainy season to include the dry months, a feat previously unattainable due to high seedling mortality. Further, these findings reflect similar findings with other hydrogels, suggesting that improved seedling survival and plant performance may be a general consequence of hydrogel amendments. 相似文献