• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.5
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• pp.381-388
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• 2004

In Korea, production of super sweet corn has been economically feasible and is substituting for traditional sweet corn due to better flavor in recent years. Major limiting factors for super sweet corn production are low field emergence and low seedling vigor. The optimum water potential (WP) for the priming of normal and aged seeds of dent, sweet (su) and super sweet (sh2) corns was studied to improve low seed quality. Seeds were primed at 0, -0.3, -0.6, -0.9, and -1.2 MPa of polyethylene glycol (PEG) 8000 solution at $15^{\circ}C$ for 2 days. Priming effects differed depending on the type of corn, seed quality, and WP of PEG solution. Although WP of priming solution did not influence the emergence rate of extremely high quality normal dent corn seeds, it reduced time to $50\%$ emergence (T50) and increased plumule weight. In contrast, the emergence rate of aged field corn was improved by seed priming at 0 MPa and plumule weight and $\alpha-amylase$ activity was enhanced. The optimum WP for both normal and aged sweet and super sweet corn seeds was between -0.3 and -0.6 Mpa. At the optimum WP emergence rate, $\alpha-amylase$ activity, and content of DNA and soluble protein increased, while T50 and leakage of total sugars and electrolytes reduced.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.350-354
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• 2009

In this work, polymer - inorganic composites have prepared using polymer such as polyethylene glycol (PEG)/poly (methyl methacrylate, PMMA) and inorganic nanofillers materials such as TiO2 nanotubes (TiNTs)/carbon nanotubes (CNTs). The extensive structural, morphological and ionic properties revealed that the high surface area and tubular feature of nanofillers improved the interaction and cross-linking to polymer matrix which is significantly enhanced the ionic conductivity and electrical properties of composite electrolytes. Comparably high conversion efficiency ~4.5% has been observed by using the newly prepared PEG-TiNTs composite solid electrolyte as compared with PMMA-CNTs electrolyte based DSSCs (~3%). The detailed comparative properties would be discussed in term of their structural, morphology, ionic and photovoltaic properties.

• Clinical and Experimental Pediatrics
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• v.51 no.4
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• pp.391-395
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• 2008

Purpose : This study was performed evaluate optimal dose for disimpaction, efficacy and safety of PEG 4000 in children with chronic functional constipation. Methods : Eighty six children with chronic functional constipation were enrolled in this prospective study at Konkuk university hospital March, 2003 through August, 2006. Success in disimpaction with PEG 4000 was defined as meeting at least two out of three criteria; resolution of chief complaint, getting easiness of defecation with respect to frequency of bowel movement and hardness of stool based on defecation diary, and decrease in fecal impaction on simple abdominal X-ray test. Adverse effects of PEG 4000 were monitored clinically and biochemically. Results : Eighty three out of 86 children completed the study, and success rate of disimpaction was 99% (82/83). The mean dose of PEG 4000 for disimpaction was $0.93{\pm}0.28g/kg/day$ (0.4-2.0 g/kg/day, Max.: 30 g/day). Frequency of bowel movement increased ($5.02{\pm}2.71/wk$ vs. $11.25{\pm}5.43/wk$) in most children (79/83). Fecal impaction on simple abdominal X-ray test improved with statistical significance in 25 children (P=0.0007). Because of adverse effect of PEG 4000, 3 children did not complete the study; urticaria, severe diarrhea, diarrhea and abdominal pain. One 6-year-old girl who completed the study complained tingling sensation in the hand and foot without laboratory abnormality (4/86, 4.7%). Laboratory test revealed hyperosmolality without clinical symptom in 1 child, and eosinophilia in 6 children. Conclusion : The average safe and effective dose of PEG 4000 for disimpaction was $0.93{\pm}0.28g/kg/day$ (0.4-2.0 g/kg/day, Max : 30 g/day) in children with chronic functional constipation.