• Journal of Ecology and Environment
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• v.41 no.9
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• pp.271-280
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• 2017

Background: Soil microorganisms play key roles in nutrient cycling and are distributed throughout the soil profile. Currently, there is little information about the characteristics of the microbial communities along the soil depth because most studies focus on microorganisms inhabiting the soil surface. To better understand the functions and composition of microbial communities and the biogeochemical factors that shape them at different soil depths, we analyzed microbial activities and bacterial and fungal community composition in soils up to a 120 cm depth at a fallow field located in central Korea. To examine the vertical difference of microbial activities and community composition, ${\beta}$-1,4-glucosidase, cellobiohydrolase, ${\beta}$-1,4-xylosidase, ${\beta}$-1,4-N-acetylglucosaminidase, and acid phosphatase activities were analyzed and barcoded pyrosequencing of 16S rRNA genes (bacteria) and internal transcribed spacer region (fungi) was conducted. Results: The activity of all the soil enzymes analyzed, along with soil C concentration, declined with soil depth. For example, acid phosphatase activity was $125.9({\pm}5.7({\pm}1SE))$, $30.9({\pm}0.9)$, $15.7({\pm}0.6)$, $6.7({\pm}0.9)$, and $3.3({\pm}0.3)nmol\;g^{-1}\;h^{-1}$ at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively. Among the bacterial groups, the abundance of Proteobacteria (38.5, 23.2, 23.3, 26.1, and 17.5% at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively) and Firmicutes (12.8, 11.3, 8.6, 4.3, and 0.4% at 0-15, 15-30, 30-60, 60-90, and 90-120 cm soil depths, respectively) decreased with soil depth. On the other hand, the abundance of Ascomycota (51.2, 48.6, 65.7, 46.1, and 45.7% at 15, 30, 60, 90, and 120 cm depths, respectively), a dominant fungal group at this site, showed no clear trend along the soil profile. Conclusions: Our results show that soil C availability can determine soil enzyme activity at different soil depths and that bacterial communities have a clear trend along the soil depth at this study site. These metagenomics studies, along with other studies on microbial functions, are expected to enhance our understanding on the complexity of soil microbial communities and their relationship with biogeochemical factors.

• Proceedings of the Korean Society for the Gifted Conference
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• 2004.11a
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• pp.125-148
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• 2004

본 연구는 우수한 학업 성적을 보이는 재미 한인 영재 청소년들이 민족적 정체감을 어떻게 형성해 나가는지를 알아보는데 그 목적이 있다. 이를 위해 미국 뉴욕의 학업영재아를 위한 고등학교에 재학중인 25명의 한인 영재아들을 대상으로 Phinney의 민족적 정체감 평가지가 사용되었다. 민족적 정체감의 평가를 위해 3가지의 민족 정체감 구성요인들이 사용되었는데, 이들은 민족적 자기 정의, 민족집단에 대한 평가와 민족집단에 대한 참여이다. 개방형 문제에 응답을 한 학생들은 두 명의 독립적인 관찰자에 의해, 자신이 정의한 민족집단에 대한 탐구와 헌신의 정도에 따라, 3단계의 민족 정체감 발달 단계로 나누어졌다. 이 3단계 중 첫번째 단계는 자신이 속한 민족집단에 대한 무관심과 낮은 참여도를 보이는 민족 정체감 무관심의 시기이고, 두 번째 단계는 자신의 민족집단에 대한 관심을 가지고 그 집단의 역사와 철학, 문화, 그리고 주류사회 속에서 해당 민족집단의 사회적 위치와 편견 등에 대해 관심과 참여를 보여주는 민족 정체감 탐구의 시기이며, 마지막 단계는 민족 정체감 완성 시기로, 자신을 그 집단의 구성원으로 완전히 수용하면서, 민족적 정체감에 안정된 모습을 보이는 단계이다. 각 민족 정체감 구성요소들과 민족 정체감 발달 단계내의 집단차를 논의하기 위해 ANOVA가 사용되었다. 연구에 참여한 대부분의 영채아들은 자신을 재미아시아인이 아니라, 한국인 혹은 재미동포로 정의하였고, 이러한 민족적 자기 정의는 학생들의 민족집단에 대한 평가도와 참여도에 중요한 역할을 한다는 것을 알 수 있었다. 또한 민족집단에 대한 긍정적인 평가는 민족집단에 대한 활발한 참여와 밀접한 관련성을 가지고 있었다. 연구에서 나타난 결과들을 바탕으로 재미 한인 영재 청소년들이 높은 자아 존중감을 지닐 수 있도록, 현재 교육현장과 실생활에서 활용할 수 있는 여러 방안들과 함께, 앞으로 필요한 보다 많은 연구를 위한 제언이 제시되었다. 사고력 계발에 보다 충실할 수 있도록 내용의 폭을 넓히고 접근방법을 달리하는 심화 중심으로 교육과정을 구성하고 운영한다고 하였다. 그러나 현재 개발된 교육과정 편성과 운영은 창의성 교육의 구현보다는 압축형 속진 교육과정의 특성이 강하여, 이와 같은 운영지침을 실현하기 어려운 것이 현실이므로 교육과정 편제의 개선이나 운영지침에 적합한 교육내용의 개발이 시급히 이루어져야 할 것이다. 둘째, R&E(Research ＆ Education)는‘연구를 통한 교육’,‘교육을 통한 연구’를 의미하며 과학영재교육과정의 가장 큰 특징이라 할 수 있는 자율연구와 위탁교육을 위한 프로그램이다.여주는 것으로 나타났다.보였다. 5. L값은 살균처리의 경우 저장 30일 이후 약간 어두워지는 경향을 보였고, 121$^{\circ}C$ 살균처리에서 높은 값을 보였다. 대체로 저장온도가 높고 저장기간이 길어질수록 약간 밝아지는 경향을 보였다. 적색도는 인삼 첨가구의 경우 상온 및 냉장저장에서 10$0^{\circ}C$ 살균이 121$^{\circ}C$ 처리구 보다 약간 높은 값을 보였다. 저장기간에 따른 적색도의 변화는 인삼과 송이 첨가구에서 비교적 안정적이었다. 황색도는 상온 및 냉장저장에서 저장기간에 따라 약간 감소하는 경향을 보인 후 상온저장 50일 째, 냉장 60일 째 가장 높게 나타났다. 121$^{\circ}C$ 살균처리구가 10$0^{\circ}C$ 처리구보다 약간 높은 경향을 보였다.^{\circ}C$$,에서는 20시간 가열시 0.706$\mu\textrm{g}$/kg으로 가장 높게 생성된 후 서서히 감소하였다. 그러나 산값과 공액이중산값은 계속 증가하는 양상을 나타냈다. 즉 B(a)P생성과 산패도 변화사이에는 일정한 관계를 나타내지는 않았다.ve(+)의 상관관계가 있었다.l

• Research in Community and Public Health Nursing
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• v.14 no.3
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• pp.375-384
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• 2003

The purpose of this study is to identify the amount of social support and quality of life perceived by elderly people in rural areas and to examine the relationship between social support and quality of life in an effort to provide the basic data for effective nursing intervention to enhance quality of life among elderly people. Data were collected from a sample of 220 elderly people aged over 60 from a stratified probability method from one rural area in South Jeolla province from Aug. 15 to Sep. 15, 2002. For data collection, pre-educated researchers visited the participants' homes and surveyed them face-to-face. The statistical analysis was performed using the SAS program along with t-test, ANOVA, and Pearson Correlation. The findings were as follows: 1. The most socially supportive people they answered were Spouses (57.28%), followed by children, friends/neighbors, in descending order. In terms of satisfaction about social support, the subjects felt the most satisfaction from spouses, followed by friends/neighbors, children, in descending order. 2. The participants' perceived social support was 26.0 and the highest score was 108.0 out of 125. Also, the average score and average grade point was 81.7 and 3.35, respectively. A comparison of the average grade points per items within sub-areas of social support revealed financial aid(3.56), informative support(3.34), emotional support (3.27), and evaluation support(3.22). 3. Their perceived social support had statistically significant differences in terms of how much they earned (F=18.56, p= .00001) and whether they had family members living together (F=2.68, p= .0512), quality of life had statistically significant differences in terms of how much they earned (F=35.34, p= 0.00001). 4. The quality of life they perceived was the lowest score 47.0, the highest score 196.0, average score 145.7, and average grade points 3.28. A comparison of the average grade points per items within sub-areas of quality of life revealed neighbor relationships(3.97), self-esteem(3.49), family relationships(3.35), economic conditions 3.12), physical health (2.98), and psychological health(2.74). 5. The relationship between the amount of the subjects' social support and quality of life was significantly correlated (r=.696, p< .001). The findings revealed that social support for elderly people in rural areas was a greatly effective factor on their quality, of life. Also, it was shown that the larger the social support for the elderly, the greater the quality of life for them. Therefore, it is necessary to foster geriatric nurse specialists and develop nursing intervention programs connected with health care and social wellbeing in order to enhance the quality of life of elderly people in rural areas. Also, it is necessary to develop effective models for community and its applications, which will playa leading role for elderly people.

• Applied Biological Chemistry
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• v.26 no.2
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• pp.125-131
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• 1983

Formal net charges, bond populations, atomic orbital coefficients, energy components and conformation of dimethyl-2,2-dichlorovinylphosphate have been studied theoretically by using the CNDO/2 molecular orbital calculation method in attempt to describe the reactivity and the stability of the molecule. From the analysis of rate equation, molecular orbital calculations and identification of the hydrolysis products, 2,2-dichloroacetaldehyde and dimethylphosphoric acid, a mechanism of the hydrolysis of dimethyl-2,2-dichlorovinylphosphate(DDVP) has been proposed. The hydrolysis of DDVP proceeds through the mechanism of nucleophilic addition, typical Micheal reaction in basic media. Therefore, it appears probable that the attack by strong nucleophile, hydroxide ion occurs at the increased positive charge $C_2({\alpha})$ atom of a staggered conformation due to the inductive effect (-)I>(+)R of 2,2-dichlorovinyl, electron-attracting group. And then, the hydrolytic scission involves the $C_2({\alpha})-O_3$, ${\pi}-anti-bonding\;orbital({\pi}^*)$ in the subsequent reaction in aqueous solution.

• Journal of Korea Port Economic Association
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• v.37 no.1
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• pp.1-18
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• 2021

A coastal marine ranching project in Uleungdo had been conducted for 5 years from 2013 to 2017 with investment costs of 5 billion won, for the special purpose of the deployment of artificial reefs, the release of young fishes. The paper focuses on an ex-post analysis of the economic feasibility for the project after completing the project, which is apart from a preliminary viability. For economic analysis, the economic benefits are derived from direct benefits including increasing effects of fisheries income and saving effects of harvesting costs, and indirect benefits including increasing effects of recreational fishing and preservation effects of coastal marine ecosystems while economic costs include releasing and purchasing costs of artificial reef and juvenile fish, R&D costs, maintenance costs and harvesting costs. The result shows that the project should not be accepted according to NPV=-0.125 billion won, IRR=4.5% and B/C ratio=0.98 under Scenario 1 which considers direct benefits and indirect benefits excluding the preservation values, while the project should be accepted under Scenario 2 indicating NPV=30.9 billion won, IRR=11.3% and B/C ratio=1.49 which considers the direct benefits as well as the indirect ones including the preservation values, based on 4.5% of the social rate of discount.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.2
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• pp.209-216
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• 2019

Objective: We compare the effects of three different approved sources of supplemental zilpaterol on growth-performance responses and carcass characteristics of finishing lambs. Methods: Twenty four Pelibuey${\times}$Katahdin lambs ($46.75{\pm}2.43kg$) were used in a 33-day feeding trial. Lambs were fed a dry rolled corn-based finishing diet. Treatments consisted of the non-supplemental basal diet (Control) versus the basal diet supplemented with 125 mg zilpaterol/kg of diet (as fed basis) from three commercial sources marketed in Mexico: Zilmax (ZIL), Grofactor, and Zipamix. Results: Compared to controls, zilpaterol (ZH) supplementation did not affect dry matter intake (DMI), but increased carcass adjusted daily weight gain (ADG, 36.7%), gain efficiency (34.2%), and dietary net energy (26.0%), and decreased (23.4%) the ratio of observed:expected DMI. Compared to controls, supplemental ZH increased hot carcass weight (6.4%), dressing percentage (3.2%), m. longissimus thoracis (LM) area (15.6%), and shoulder muscle:fat ratio (28.7%), but decreased kidney-pelvic-heart fat, and fat thickness. Supplemental ZH increased 10.9% and 14.3% whole cut weight of loin and leg, respectively, and the proportion (as percentage of cold carcass weight) of leg (4.3%). These increases were reflected in greater forequarter and hindquarter weights. Lambs fed ZH increased (4.6%) empty body weight (EBW) and reduced (14.7%) liver/spleen weight (as g/kg EBW). Likewise, ZH supplementation tended (p = 0.08) to lower (8.9%) visceral fat. Growth performance, energetic efficiency, hot carcass weight, dressing percentage, LM area and whole cuts were not different across supplemental ZH sources. However, compared with non-supplemented controls, only ZIL appreciably decreased carcass fat distribution, including fat thickness, percentage kidney pelvic and heart fat, shoulder fat, and visceral fat. Conclusion: Supplemental ZH increases ADG, gain efficiency, carcass dressing percentage, and LM area. The magnitude of these responses was similar among ZH sources. Nevertheless, compared with non-supplemented controls, only ZIL appreciably decreases carcass fat. The basis for this is uncertain, but indicative that some practical differences in zilpaterol bio-equivalency may exist across commercial sources tested.

• Korean Journal of Food Science and Technology
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• v.54 no.2
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• pp.115-125
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• 2022

Flavonoids are bioactive plant metabolites that have a range of beneficial effects on human health. Quercetin 4'-glycoside (Q4'G), quercetin 3,4'-diglycoside (Q3,4'G), and quercetin aglycone (QA) are the main flavonoids found in onions. QA, in particular, is likely to have a greater biological effect than glycosides. To develop an onion extract with high quercetin content, the optimal extraction conditions for red onion powder containing the outer layer of the onion were determined. The effects of acid treatment on the concentration of quercetin glycosides and QA were evaluated. The flavonoids of red onion powder were optimally extracted under 60-70% ethanol at 70℃ for 2 h. The deglycosylation of Q3,4'G and an increase in Q4'G content occurred within 6 h of 0.2% acetic acid treatment. The QA content and deglycosylation of Q4'G eventually peaked at 24 h. In addition, QA content and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were highly correlated, with a correlation coefficient of 0.90.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.539-559
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• 2021

Agricultural ecosystem biodiversity monitoring and community variation analysis of insects were conducted from 2016 to 2018 in selected conventional and organic farming fields in Goesan district, Chungcheongbuk-do, South Korea. The total number of 1,125 species in 16 orders and 207 families were identified. The numbers of species collected in the locations practicing organic farming were greater than the conventional farming both in the paddy fields (564 vs. 383 species) and the upland fields (471 vs. 365 species). Among them, Hemiptera had the most abundant of species, followed by Diptera, Hymenoptera, Coleoptera and Araneae. We calculated various index values of biodiversity (diversity index H', richness index R, evenness index J', dominance index D, and similarity index QS) based on quantitative measurements of species and individuals collected over three years of field monitoring. Variations in biodiversity index values in different agricultural systems show that the positive effect of organic farming is to produce more biodiversity than conventional farming systems. When compared to other index results reported in Korea, Japan and China, the richness index was higher and other index values were at similar levels.

• Journal of Animal Science and Technology
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• v.64 no.2
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• pp.353-364
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• 2022

The present study aimed to assess the feasibility of increasing the slaughter weight (SW) of non-lean finishing pigs to improve their meat quality. A total of 36 (Landrace × Yorkshire) × Duroc gilts and barrows were slaughtered at 115 (Av), 125 (Hi), or 135 (XHi) kg, followed by physicochemical analyses and sensory evaluation on their longissimus dorsi (LD) and Semimembranosus (SM) muscles. Backfat thickness was greater (p < 0.05) for the XHi (31.2 mm) and Hi (29.3 mm) groups than for Av (25.0 mm). Dressing percentage and yield of the belly per whole carcass were also slightly greater for XHi and Hi vs. Av. The intramuscular fat (IMF) content of SM was greater for XHi (2.64%) than for Av (1.83%) and Hi (2.04%) and also was correlated with SW (r = 0.55). The pH value, lightness, redness, drip loss, shear force, and moisture and protein contents of LD and SM, as well as IMF content of LD, were unaffected by SW. Percentages of 14:0, 16:0, and total saturated fatty acids (FA) were less for Hi and XHi vs. Av in SM, those of total unsaturated FA, 18:2, 20:4, and n-6 being opposite; FA composition of LM was not influenced by SW except for a reduced 18:0 percentage for XHi vs. Av. The sensory score was less for XHi vs. Av for odor in fresh LD and SM, and less for Hi and XHi vs. Av for aroma in fresh LM; scores for color, drip loss, marbling, and acceptability were unaffected by SW. As for cooked muscles, none of the scores for color, aroma, flavor, juiciness, tenderness, and acceptability was affected by SW, except for a greater LD color score for Hi and XHi vs. Av. Collectively, the results suggested that the increased yield of the carcass and belly due to increased SW is outbalanced negatively by excessive backfat deposition in production efficiency, whereas the SW increase exerts little influence on overall sensory quality of fresh or cooked meat. Production of non-lean market pigs overweighing 115 kg therefore will be uneconomical unless consumers pay a substantial premium for the over-fattened pork.

• Journal of Mushroom
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• v.22 no.1
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• pp.22-26
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• 2024

Tricholoma matsutake is a traditional favorite food in East Asia, cultivated in fairy rings called "shiro," which are found near Pinus densiflora. For effective artificial cultivation of Tri. matsutake, microorganisms from symbiotic fairy rings are co-cultivated. In this study, one bacterial isolate (Y22_B35) and two fungal isolates (Y22_F64 and Y22_F68) displayed growth-promoting effects on Tri. matsutake mycelium (158.47, 125.00, and 122.26% enhanced growth, respectively). For identification, 16S rRNA or ITS regions from the microorganisms¡¯ genomes were sequenced. Other sequences, including BenA, CaM, and RPB2 were sequenced in the fungal isolates. The bacterial isolate Y22_B35 was identified as Bacillus cereus. Y22_F64 and Y22_F68 were identified as Umbelopsis nana and Aspergillus parvulus, respectively. To identify the effects of the dominant microorganisms on Tri. Matsutake cultivation, metagenomic analyses were performed. Discovery of these Tri. matsutake mycelium growth-promoting microorganisms and metagenomics analyses are expected to contribute to our understanding of Tri. matsutake fruiting body growth and construction of biomimicry.