• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.2
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• pp.69-76
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• 2006

Fallow paddy areas have been increased due to the import of cheap agricultural product, and the unbalance between farming cost and rice price since 1990. The increasing fallow paddy area needs to be protected from the devastation by weed breeding for the re-cultivation. In this study, two fallow paddy fields managed with different water depth were selected for monitoring and analysing of water quality, water balance and plant body change. The managed fallow paddy fields were more effective in water quality purification and plants growth control than non-managed fallow paddy fields. And the fallow paddy field managed with some degree of water depth was the most effective field in terms of weed control.

• Journal of Ecology and Environment
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• v.29 no.5
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• pp.425-432
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• 2006

The tadpoles of 12 Korean anuran species, including Bombina orientalis, Bufo gargarizans, B. stejnegeri, Hyla japonica, Kaloula borealis, Rana dybowskii, R. huanrenensis, R. coreana, R. nigromaculata, R. chosenica, R. rugosa, and R. catesbeiana, were classified based on their morphological characteristics. We collected eggs or tadpoles of the 12 Korean anuran species from Gangwon, Incheon, Chungcheong, and Gyeonggi districts in 2005 and 2006 breeding seasons. When the tadpoles reached at $27{\sim}37$ Gosner's developmental stages, we described morphological characteristics of the tadpoles of each anuran species and measured their physical parameters such as total length, body length, and body mass. After that, we chose 12 morphological characteristics to identify each species and to use them as classification keys such as eye location, caudal musculature pattern, spiracle location, oral disc morphology, and labial tooth row formula. In this paper, we presented classification keys, morphological characteristics, and drawings for the tadpoles of 12 anuran species.

• Geomechanics and Engineering
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• v.12 no.1
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• pp.53-69
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• 2017

Rock burst may cause serious casualties and property losses, and how to conduct effective monitoring and warning is the key to avoid this disaster. In this paper, we reviewed both the rock burst mechanism and the principle of using electromagnetic radiation (EMR) from coal rock to monitor and forewarn rock burst, and systematically studied EMR monitored data of 4 rock bursts of Qianqiu Coal Mine, Yima Coal Group, Co. Ltd. Results show that (1) Before rock burst occurrence, there is a breeding process for stress accumulation and energy concentration inside the coal rock mass subject to external stresses, which causes it to crack, emitting a large amount of EMR; when the EMR level reaches a certain intensity, which reveals that deformation and fracture inside the coal rock mass have become serious, rock burst may occur anytime and it's necessary to implement an early warning. (2) Monitored EMR indicators such as its intensity and pulses amount are well and positively correlated before rock bursts occurs, generally showing a rising trend for more than 5 continuous days either slowly or dramatically, and the disaster bursts generally occurs at the lower level within 48 h after reaching its peak intensity. (3) The rank of EMR signals sensitive to rock burst in a descending order is maximum EMR intensity > rate of change in EMR intensity > maximum amount of EMR pulses > rate of change in the amount of EMR pulses.

• Journal of Korean Society of Forest Science
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• v.82 no.2
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• pp.122-127
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• 1993

This study was conducted to investigate characteristics related to lacquer yield and to evaluate possibility of indirect selection of Rhus verniciflua Stokes. Twenty-four lacquer trees were randomly selected for measuring growth, urushiol content and bark thickness. Urushiol content showed a significant positive correlation with outer bark thickness and secretory canal density at 1% level, and with inner bark thickness at 5% level. Bark thickness and secretory canal density could be used as indicators for high urushiol content within bark and thus for high lacquer yield. Mass selection for high lacquer yield was made based on urushiol content within bark. Sixteen individuals with the highest urushiol content value were selected for breeding. As expected, the selected trees had thicker bark, higher density of secretory canal, better developed secretory canals compare to the non-selected lacquer trees.

• Food Science and Biotechnology
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• v.18 no.6
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• pp.1470-1475
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• 2009

The seed coat of the black soybean contains 3 main anthocyanins such as delphinidin-3-O-$\beta$-glucoside, cyanidin-3-O-$\beta$-glucoside, and petunidin-3-O-$\beta$-glucoside. As a part of our effort on discovering and breeding new black soybean cultivars which possesses specific anthocyanin component rich, we determined the anthocyanin profiles of the 2 cultivars recently developed soybean cv. Gaechuck #1 and cv. Gyeongsang #1, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and compared their content and identity with those of previously known 10 cultivar controls. The Cosmosil-$5C_{18}$-AR-II column were selected for the analysis because of the best peak separation. The column temperature was set up at $35^{\circ}C$. The mobile phase consisting of water containing 0.5%(v/v) formic acid and methanol gave good separation between the 3 anthocyanin analytes and internal standard (quercetin 3-O-$\beta$-rutinoside) and peaks with suppressed tail. The MS/MS spectra of each individual anthocyanin standard were detected in positive electron spray ionization (ESI) modes. It was disclosed that the anthocyanin contents of the soybean cv. Gaechuck#1 and cv. Gyeongsang#1 are roughly higher than those of the 10 controls.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1097-1101
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• 2008

The objective of this study was to identify and quantify glucosinolates (GSLs) in Brassica napus cv. Hanakkori and its parents and to evaluate its potential bitter taste. 'Hanakkori' materials were cultivated with commercial chemical nutrients (20 kg/ha, N-P-K: 16-10-10) at the field. GSLs were isolated by means of extraction with 70%(v/v) boiling methanol (MeOH) followed by desulfation from those plants by reversed-phase high performance liquid chromatography (HPLC) and identified by electronic spray ionization-mass spectrometry (ESI-MS) analysis. In 'Hanakkori', 11 GSLs were identified as progoitrin, glucoraphanin, glucoalyssin, gluconapoleiferin, gluconapin, 1-methylpropyl, glucobrassicanapin, glucobrassicin, 4-methoxyglucobrassicin, gluconasturtiin, and neoglucobrassicin. The total GSL contents were 109 and 36.1 mmol/kg dry weights (d.w.) for the seeds and edible parts, respectively. The major GSLs (>5 mmol/kg d.w.) in the seeds were progoitrin (78.8), gluconapin (10.7), and glucobrassicanapin (7.81), whereas they in the edible parts were progoitrin (16.1) and glucobrassicanapin (8.58). In addition, the bitter taste in the edible parts was presumably related with the presence of progoitrin (>45% to the total GSL).

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.1
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• pp.7-12
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• 2001

Factors Affecting the Survival of Frozen Thawed Bovine In Vitro Produced Blastocysts. The effect of some factors on the post-thaw survival of a total of 240 in vitro produced bovine blastocysts was investigated using logistic regression analysis. The explanatory variables tested were: type of culture medium before freezing (TCM 199 supplemented with BSA, BSAITS (BSA+insulin+transferrin+selenium), ECS (estrous cow serum) with or without BOEC (bovine oviductal epithelial cells), age of the blastocyst (Day 7, Day 8+9), morphological appearance before freezing (distinct=Q1 or indistinct=Q2 inner cell mass) and type of cryoprotectant (glycerol, 1.0 M or ethylene glycol, 1.6 M). The survival after thawing based on the post-thaw quality and the development after co-culture with BOEC for 24 and 48 hours. Day 7 blastocysts had an almost three times better chance of survival than Day 8+9 blastocysts. Q1, Day 8+9 blastocysts had higher odds to survive after 48 hours in culture than Q2 blastocysts (p<0.05). Blastocysts produced in BSAITS medium had the best chances of survival; however, the odds were not always significant. Blastocysts frozen in glycerol had a better post-thaw quality rating than those frozen in ethylene glycol; however, the difference in post-thaw development at culture was not significant. The relationship between post-thaw quality and post-thaw development at culture was significant (p<0.05). The developmental stage and/or age of the embryo and culture medium where development up to blastocyst takes place affect the post-thaw survival of the bovine embryos.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.157-157
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• 2017

In last study, Genome-Wide Association Studies (GWAS) was conducted for cadmium content of 295 rice varieties including 137 rice core set and 157 Korea breeding varieties collected from Kongju National University. The results showed that 9 varieties had SNP allele and amino acid substitution in exon of chromosome 1. This study was aim to understanding mechanism of cadmium uptake to confirm correlation of cadmium and other mineral nutrients (Cu, Mn, Fe) among 9 rice varieties. Nine varieties were planted on polluted soil of mine in Korea and cadmium content in root, stem, leaf and it's brown rice was analyzed by ICP-MS (Inductively Coupled Plasma Mass spectrometer, Agilent 7700E, US). Results of this study showed that mechanism for cadmium uptake and accumulation was diversity among varieties. Chin-nong and Ho-nong contained higher levels of cadmium in root, but contained relatively lower levels cadmium in brown rice than other varieties. Cheong-nam, Nam-pyeong, Gan-cheok, Suan absorbed high levels of cadmium through root and then accumulated high cadmium to brown rice. Meanwhile, Yeong-deok and Su-kwang absorbed lower cadmium in root, but high cadmium was accumulated in brown rice. Correlations between cadmium and other mineral nutrients (Cu, Mn, Fe) were analyzed by using SPSS statistics 20. The contents of iron in leaf had minus correlation (p<0.05) with cooper and cadmium in root, cadmium in brown rice. Therefore understanding of cadmium uptake mechanism among varieties will be used to basic data for further breeding and phytoremediation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.1
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• pp.64-69
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• 2016

This study was conducted to develop a fast and efficient screening method to determine the quantity of fatty acid in peanut oil for high oleate breeding program. A total of 329 peanut samples were used in this study, 227 of which were considered in the calibration equation development and 102 were utilized for validation, using near infrared reflectance spectroscopy (NIRS). The NIRS equations for all the seven fatty acids had low standard error of calibration (SEC) values, while high R2 values of 0.983 and 0.991 were obtained for oleic and linoleic acids, respectively in the calibration equation. Furthermore, the predicted means of the two main fatty acids in the calibration equation were very similar to the means based on gas chromatography (GC) analysis, ranging from 36.7 to 77.1% for oleic acid and 7.1 to 42.7% for linoleic acid. Based on the standard error of prediction (SEP), bias values, and $R^2$ statistics, the NIRS fatty acid equations were accurately predicted the concentrations of oleic and linoleic acids of the validation sample set. These results suggest that NIRS equations of oleic and linoleic acid can be used as a rapid mass screening method for fatty acid content analysis in peanut breeding program.

• Journal of Animal Science and Technology
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• v.57 no.5
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• pp.20.1-20.8
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• 2015

Background: In order to prepare for the regulation about the limit of manure production, the status of manure management and the amount of nutrients in the compost discharged from Hanwoo breeding farm shall be known. This study aimed to find the practical amount of nutrients (volatile solids, VS; total nitrogen, T-N; total phosphorus, T-P) in manure, and compost samples collected from 40 Hanwoo breeding farms and the loss of the nutrients was calculated during the composting period, which supports to develop nutrient loading coefficients (NLCs) for each nutrient. Results: Although the addition of bedding materials for composting caused the increase of the VS amount before composting, the comparison of VS, N, and P amounts in between manure and compost showed the lower VS by 4 % as well as T-N and T-P amounts by 69 and 40 %, respectively, of which values were corresponded with the NLCs of 0.96, 0.31, and 0.60 for VS, N, and P, respectively, based on the questionnaire, and sample analyses. Considering with the environmental impacts including land application from Hanwoo manure, P loss should be zero before and after composting. In this regard, nitrogen loss of 50 % occurs and VS was increased by 30 %. In addition, feasible cases for the calculations based on the notification from Ministry of Environment were compared with this study. Conclusions: The development of NLCs from Hanwoo manure in this study implies that the loss of nutrients in manure occurs during the composting or storing period. The mass balances of N and P from livestock manure to land application may be overestimated over the practical values. It is necessary to build up the database about each livestock category other than Hanwoo.