• Korean Journal of Organic Agriculture
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• v.24 no.3
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• pp.435-451
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• 2016

The objective of the present study was to perform a comparative analysis of the chemical properties of the cultivation site soil and growth characteristics of organically and conventionally cultivated ginseng (Panax ginseng C. A. Meyer). Organically and conventionally cultivated ginseng samples (4-, 5-, and 6-year-old) were collected from 52 fields at 14 locations throughout Korea. The samples were collected over three years from 2013 to 2015, with the collection period between October and November of each year. In order to increase the yield of organically cultivated ginseng, the amount of nutrients was increased to match that of the conventional cultivation system, which highlights the need for proper management in accordance with the standards for chemical properties of soil. Growth duration of organic ginseng was ${\geq}60days$ shorter than that of conventional ginseng and its average yield per 1ha was 60% than that of conventional ginseng. Root weight of organically cultivated ginseng was approximately 54% that of conventionally cultivated ginseng. Rhizome diameter and body shape index of organically cultivated ginseng were lower than those of conventionally cultivated ginseng, indicating that organically cultivated ginseng was thinner and longer than conventionally cultivated ginseng. Root length was greater in 5-year-old conventionally cultivated ginseng with a low percentage of paddy-upland rotation fields. The number of rootlets was lower in 5- and 6-year-old organically cultivated ginseng with a high percentage of direct seeding cultivation. Dry weight was distinctly lower in 5- and 6-year-old organically cultivated ginseng with early defoliation than that of conventionally cultivated ginseng. Incidences of notched belly and root rot tended to be higher in conventional cultivation, with the incidence of notched belly being distinctly higher in 4- and 6-year-old roots and root rot being more prevalent in 5- and 6-year-old roots. Red discoloration and eelworm damage, which are highly affected by soil moisture, were most common in the organically cultivated 4-year-old roots. Organically cultivated ginseng showed early defoliation than conventionally cultivated ginseng, as a result, its yield and weight were low, while the incidence of physiological disorders was low. In order to increase the yield of organically cultivated ginseng, studies on cultivation technology that can overcome early defoliation, as well as soil moisture management that can minimize physiological disorders, are required.

• Radiation Oncology Journal
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• v.27 no.1
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• pp.35-41
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• 2009

Purpose: This study was designed to determine the optimum radiotherapy technique for internal mammary node (IMN) irradiation after breast-conserving surgery. Materials and Methods: We selected ten cases of early stage partial mastectomy for plan comparison. Five of the patients were treated to the right-side breast and the rest of the patients were treated to the left-side breast. For each case, four different treatment plans were made to irradiate the entire breast, IMNs and supraclavicular lymph nodes (SCLs). The four planning techniques include a standard tangential field (STF), wide tangential field (WTF), partially wide tangential field (PWT) and a photon-electron mixed field (PEM). We prescribed a dose of 50.4 Gy to the SCL field at a 3 cm depth and isocenter of the breast field. Results: The dose distribution showed clear characteristics depending on the technique used. All of the techniques covered the breast tissue well. IMN coverage was also good, except for the STF, which was not intended to cover IMNs. For the cases of the left-side breasts, the volume of the heart that received more than 30 Gy was larger (in order) for the WTF, PWT, PEM and STF. For radiation pneumonitis normal tissue complication probability (NTCP), the PWT showed the best results followed by the STF. Conclusion: Despite the variety of patient body shapes, the PWT technique showed the best results for coverage of IMNs and for reducing the lung and heart dose.