• Journal of Life Science
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• v.10 no.4
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• pp.317-325
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• 2000

A six parent dialled analysis was conducted to get basic information for improving yield of upland cotton. Heterosis, combining ability, genetic components and correlation coefficients for boll length, boll width, boll weight, 100 seed weight, lint weigth per boll and lint percentage were studied. Estimates of heterosis for all characters and heterobeltiosis for boll weight and lint weight per boll showed positive values. In general combining ability effect, 'Muan' and 'Imsung' showed highely positive effect in all characters. In specific combining ability effect, the combinations of 'Seungju${\times}$Imsung$.$Seosan${\times}$Imsung' for bll length, 'Cheju${\times}$Imsung$.$Seung${\times}$Imsung' for boll width, 'Cheju${\times}$Muan$.$Cheju${\times}$Imsung' for boll weight, 'Cheju${\times}$Soonchun$.$Muan${\times}$Imsung' for 100 seed weight, 'Soonchun${\times}$Muan' for lint weight per boll and 'Soonchun${\times}$Seosan$.$Seungju${\times}$Muan' for lint percentage showed highly positive effect. Partial dominance was observed for boll length, boll weight, 100 seed weight and lint weight per boll, complete dominance for boll width and overdominance for lint percentage. The number of effective gene group was estimated as one for all characters. The estimates of narrow and broad sense heritabilities were high for all characters except as one for all characters. The estimates of narrow and broad sense heritabilities were high for all characters except lint percentage. Correlation coefficients among the boll length, boll width, boll weight, 100 seed weight and lint weight per boll were positive, whereas lint percentage was negatively correlated with other characters.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.136-141
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• 1998

To give some information on the harvest and storage of Chinese yam (Dioscorea opposita), the experiment was done to examine the effect of its harvesting date and storage method on tuber weight, tuberrelated characters during the storageor at the end of storage. The yam tubers harvested 4 times at 20 days interval from Oct. 15 were stored with different storage methods(pit, room and cold temperature) and on Mar.15. all the characters were measured. Fresh weight of the tuber harvestedafter Nov. 5 and stored were greater than that done on Oct. 15 while dry tuber weight did not have any difference between the harvesting dates. The fresh weigth done directly from the field on Mar. 15 was higher compared to the other harvesting dates owing to its higher moisture content. The rate of sound tuber stored at room or cold temperature condition was higher than that at the field at which the rate was greater at the harvest after late nov. compared to the earlier harvests. Although the two storages were similar at sound tuber rates and marketable yield, the tuber weight was more reduced when stored at room temperature than when done at cold temperature . Brightness and value 'b' of chromaticaity realted to the tuber coloring and sugar content were higher but moisture content was lowerwhen harvested on Oct. 15 than the other havesting dates. All the characteristics realted to the marketability after storage were nearly same when stored at room and cold temperature. Value 'a' of chromaticity and sugar content were higher when harvest on Mar. 15 than when harvested before Dec. 15 but the 'b' value and mositure content were reverse results.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.3
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• pp.73-85
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• 2002

The purpose of this study was to develop prediction models for plant species abundance by stream restoration. Generally the stream plant is affected by stream gemophology. So in this study, the relationship between the vegetation abundance and stream gemophology was developed by multiple regression analysis. The stream characteristics utilized in this study were longitudinal slope, transectional slope, micro-landforms through the longitudinal direction, riparian width and geometric mean diameter and biggest diameter of bed material, and cumulated coarse and fine sand weight portion. The Pyungchang River with mountainous watershed and the Kyungan stream and the Bokha stream in the agricultural region were selected and vegetation species abundance and stream characteristics were documented from the site at 2~3km intervals from the upper stream to the lower. The Models for predicting the vegetation abundance were developed by multiple regression analysis using SPSS statistics package. The linear relationship between the dependant(species abundance) and independant(stream characteristics) variables was tested by a graphical method. Longitudinal and transectional slope had a nonlinear relationship with species abundance. In the next step, the independance between the independant variables was tested and the correlation between independant and dependant variables was tested by the Pearson bivariate correlation test. The selected independant variables were transectional slope, riparian width, and cumulated fine sand weight portion. From the multiple regression analysis, the $R^2$for the Pyungchang river, Kyungan stream, Bokga stream were 0.651, 0.512 and 0.240 respectively. The natural stream configuration in the Pyungchang river had the best result and the lower $R^2$for Kyunan and Bokha stream were due to human impact which disturbed the natural ecosystem. The lowest $R^2$for the Bokha stream was due to the shifting sandy bed. If the stream bed is fugitive, the prediction model may not be valid. Using the multiple regression models, the vegetation abundance could be predicted with stream characteristics such as, transection slope, riaparian width, cumulated fine sand weigth portion, after stream restoration.

• Resources Recycling
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• v.3 no.1
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• pp.9-16
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• 1994

Fine cobalt metal powders was produced from domestic Stellite scrap by decomposing it with molten sodium hydroxide. Complete decomposition of the scrap could be obtained with the weigth ratio of sodium hydroxide to Stellite being about 2 at the temperature ranges of $750~800^{\circ}C$ for an hour. The cobalt-bearing compound was identified as $Co_2O_3{\dot}H_2O$ by X-ray analysis and D.T.-T.G.a.. The compound was then digested in HCI to form cobalt chloride, and after iron removal by adjusting the pH of the solution, cobaltous or cobaltic hydroxide was precipitated at the pH of about 13 or 4, respectively. The precipitates were reduced by hydrogen in the temperatures of $400~500^{\circ}C$ to fine cobalt powders of high purity with the size of 1.0 to $1.5\mu\textrm{m}$. The recovery of cobalt from Stellite scrap was about 75~86% by weight.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.111-116
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• 1996

Polyphenol oxidase(PPO) isolated from the crude extract of ascidian, Halocynthia roretzi, showed higher affinity for catechol than tyrosine or DL-DOPA. Successful enzyme assay could be performed at $25^{\circ}C$, 10min. by mixing 0.2ml of crude enzyme extract with 2.8ml of 0.13M catechol in 0.1M sodium phosphate buffer(pH 6.4). The specific activity of PPO which had been purified with a combination of ammonium sulfate treatment, ion exchange chromatography on DEAE-cellulose, and gel filtration on Sepharose 6B was 13-fold disc gel electrophoresis. The activity of PPO was stable from pH 5.0 to 8.0 and showed the peak activity at pH 6.4 .The optimum reaction temperature for PPO oxidation on catechol was 35$^{\circ}C$ and those enzyme were heat stable up to 4$0^{\circ}C$. Molecular weigth of the enzyme was estimated about 170kDa. One molecule was found to be composed of gour subunits. Two of them had molecular weigh of 55kDa and the others 30kDa. The {TEX}$K_{m}${/TEX} values, {TEX}$V_{max}${/TEX} and catalytic efficiency({TEX}$V_{max}${/TEX}/{TEX}$K_{m}${/TEX}) for catechol were 0.12mM, 2.5mM/liter/min. and {TEX}$0.18min^{-1}${/TEX} respectively. The substrate affinity and electrophorectic pattern suggested that the enzyme of ascidian was considered to be not tyosine but catechol oxidase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.488-493
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• 1991

The characteristics of endogenous and exogenous polygalacturonase(PG) produced from L. acidophilus were investigated as one of the serial studies on the fermentation of Chinese cabbage kimchi using L. acidophilus. Apparent molecular weigth of endogenous and exogenous PG were estimated to be 420,000 and 500,000 daltons by the method of gel filtration and Vmax of the enzymes 8.0 and $0.3{\mu}mol$ galacturonic acid/ml/30min, respectively and Km of the enzymes were 4.0mg/ml. The optimum temperature, pH and salt concentration of the both enzymes were the same and appeared to $30^{\circ}C$, 5.5 and 2~3%, respectively. The activities of the endogenous and exogenous PG all were severely decreased by increasing of temperature to $90^{\circ}C\;from\;60^{\circ}C$ and its remained activities at $60^{\circ}C\;and\;90^{\circ}C$ were 50%, 58%, and 19%, 5%, respectively.

• Journal of Nutrition and Health
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• v.31 no.8
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• pp.1283-1294
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• 1998

This study was conducted to investigate nutritional status by anthropometric meas-urement and to assess the validity of indicators for nutritional status of preschool children. Health examinations, including blood and urine tests, were done for 799 childern aged 2 to 6 years. The mean anthropometric measurements of height, weight , head circumference, and chest circumference were 90.2cm, 13.9kg, 47.7cm, 50.9cm for 2 years (n=13), 94.8cm, 15.2kg, 43.3cm, 47.0cm for 3 years(n=125), 100.7cm, 16.4kg, 46.2cm, 50.5cm for 4 years(n=272), 106.5cm, 18.1kg, 48.8cm, 53.8cm for 5 years(n=253), 113.0cm 20.4kg, 50.4cm 56.9cm for 6 years(n=136), respectively. All anthropometric measureemnts were significantly different by age and sex. The results of physical examinations excluding dental examination were normal for all studied children. Urine test results were also normal for the subjects. The most common blood type was A and the rarest one was type AB. The mean hemoglobin concentration was 11.84g/dl for boys(n=398), 11.86g/dl for girls, and 11.85kg/dl for all. The percentage of childeren whose hemoglobin concentration was less than 11.0g/dl was 21.6% for boys and 18.9% for girls. The percentage of children whose height for age, weight for age, and weight for height were in the rang of median $\pm$1 standard devication(S.D) was 71.7% , 65.6%, and 67.0% for each indicator. Obese childeren whose weight for height or weigth for age was more than median +2S.D. were 5.2% while tall children whose height for age was more than median +2S.D, were 1.8% . Past and recent nutritional status of most children(87.2%) were assessed as normal by the combination of three indicators(height for age, weight for age, weight for height). The percentate of coincidence between for height) and one assessed by anthropometric measurements (height for age, weight for age, weight for height) and one assessed by physicial was 59.6%, 69.3% and 67.8% for each indicator, respectively. The distribution of subjects by height for age was significantly different between normal and anemic groups. With these results , the nutritional status of children the studied was normal. The anthropometric measurements reflected the nutritional status of childeren relatively well. In conclusion, in comparison with biochemical meausurements anthropometric measurements are relatively simple and effective indicators for nutritional assessement of children in large health and nutrition suveys in Korea.

• Korean Journal of Medicinal Crop Science
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• v.10 no.5
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• pp.379-383
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• 2002

The significant chemical components estimating the quality and growth characteristics in different parts of tea plants were compared and analyzed in the shoots of shading tea plants. The results are summarized as follows. The leaves length, leaves width and weigth of 100 buds in the leaves were increased with growing, while the leaf moisture was decreased. The contents of total nitrogen, caffeine, vitamin C and saponin in the leaves were decreased with growing, while those of total amino acid and chlorophyll were the highest in the 4th leaves and in 3rd leaves, respectively. The content of tannin ranged from 9.53% to 11.23%. The content of tannin at the 1st leaves was the highest as 11.24%, but that of the 4th leaves was the lowest as 9.53%. the content of fatty acid at the 2nd leaves was the highest as 3,594mg/100g, and that of the 5th leaves was the lowest as 2,782mg/100g. The contents of palmitic acid and stearic acid were the highest in the 5th leaves, but those of oleic acid, linoleic acid and linolenic acid were the highest at the 2nd leaves. In conclusion, the 5th leaves among tea shoots plucked after shading for 15 days could be used to manufacture powder green tea.

• Journal of Nutrition and Health
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• v.29 no.6
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• pp.578-589
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• 1996

This study was performed to invstigate the effect of dietary protein level and source on cadmium intoxicification in rats. Forty-eight male rats of Sprague-Dawley strain weighing 171$\pm$3g were blocked into 8 groups of 6 animals according to body weigth, and were raised for 30days. Eight experimental diets different with cadmium(0ppm, 400ppm)and protein(15%, 40%) levels and protein source[casien, I.S.P.(isolated soy protein)] were given to animals for 30days. Food intake, weight gain, food efficiency ratio, liver weight, kidney weight and femur weight were lower in cadmium added group, and higher in high protein groups(40% protein) than medium protein groups(15% protein). But, dietary protein source had no influence on them. Cadmium concerntration of liver was higher in rats fed casein than I.S.P. groups, and cadmium concentration in intestine was higher in high protein groups. In femur both high protein and I.S.P.diets increased cadmium concentrations. MT concdentrations in liver, kidney and intestine were higher in cadmium added group, and kidney intestine MT concentration were higher in high protein group. Absorption and retention rates of cadmium were lower in rat fed I.S.P. than animal fed casein among medium protein groups and cadmium concentration in blood and liver of I.S.P groups were lower than casein groups. But absorption and retention rates of cadmium were similar in high casein and I.S.P. groups. Renal damage by cadmium administration was not seen in all groups. Absorption rates of zinc and copper competing with cadmium in absorption process were lower in high protein groups than medium protein groups and lower in rats fed I.S.P. than casein. In conclusion, weight gain, F.E.R, and MT concentraion of high protein groups were higher than those of medium protein groups and absorption and retention rates of cadmium were lower in high protein groups. From these results, it was shown that cadmium toxicity was alleviated by high dietary protein. Meanwhile, the effect of dietary source on the cadmium toxicity was different with protein level. In medium protein groups absorption and retention rates of cadmium were much lower in rats fed I.S.P. than casein. In high protein groups, cadmium toxicity was not influenced by protein source and absorption and retention rates of cadmium were not different between casein and I.S.P. groups.

• Journal of Adhesion and Interface
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• v.7 no.3
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• pp.1-9
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• 2006

To improve the poor mechanical and thermal properties of conventional PMMA bone cement, we impregnated three types of polyethylenes (PE) (200, 3,800, and 8,000 kg/mol). MMA/xylene solution was used to modify the surfaces of PEs and new composite PMMA bone cements were manufactured by impregnating 3 wt% of the surface-modified PEs into conventional PMMA bone cement. As molecuar weigth of PE increased, tensile strengths of the manufactured composite PMMA bone cements were improved. Also, we confirmed that the curing temperatures of the composite PMMA bone cements decreased from near $100^{\circ}C$ to $40^{\circ}C{\sim}80^{\circ}C$.