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Genetic Variation and Phylogenetic Relationship of Taraxacum Based on Chloroplast DNA (trnL-trnF and rps16-trnK) Sequences (엽록체 DNA (trnL-trnF, rps16-trnK) 염기서열에 의한 국내 민들레속 유전자원의 유전적 변이와 유연관계 분석)

  • Ryu, Jaihyunk;Lyu, Jae-il;Bae, Chang-Hyu
    • Korean Journal of Plant Resources
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    • v.30 no.5
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    • pp.522-534
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    • 2017
  • This study was investigated genetic variation in 24 Taraxacum accessions from various regions in South Korea based on the sequences of two chloroplast DNA (cpDNA) regions (trnL-trnF and rps16-trnK). T. mongolicum, T. officinale, and T. laevigatum were triploid, and T. coreanum and T. coreanum var. flavescens were tetraploid. The trnL-trnF region in native Korean dandelions (T. mongolicum, T. coreanum, and T. coreanum var. flavescens) were ranged from 931 to 935 bp in length, and that of naturalized dandelions were ranged from 910 bp (T. officinale) to 975 bp (T. laevigatum) in length. The rps16-trnK region in T. mongolicum, T. coreanum, T. coreanum var. flavescens, T. officinale, and T. laevigatum was 882-883 bp, 875-881 bp, 878-883 bp, 874-876 bp, and 847-876 bp, respectively, in length. The sequence similarity matrix of the trnL-trnF region ranged from 0.860 to 1.00 with an average of 0.949, and that of the rps16-trnK region ranged from 0.919 to 1.000 with an average of 0.967. According to the phylogenetic analysis, the Korean native taxa and naturalized taxa were divided independent clade in two cpDNA region. T. coreanum var. flavescens clustered only with T. coreanum, and there were no significant differences in their nucleotide sequences. The finding that two accessions (T. coreanum; Jogesan, T. mongolicum; Gangyang) had a high level of genetic variation suggests their utility for breeding materials.

Exploratory Study on the Phenomena of Entrepreneurship Education in Food and Agriculture Sectors Based on the Grounded Theory Approach (근거이론접근법에 기반한 농식품분야 창업교육현상에 관한 탐색적 연구)

  • Seol, Byung Moon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.3
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    • pp.33-46
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    • 2020
  • This study analyzes the entrepreneurship education phenomena for agri-food entrepreneurs whose main business is the production of agricultural products and the sale of processed products, using the qualitative study Strauss & Corbin(1998)'s evidence theory approach. From the entrepreneur's point of view, I would like to summarize the phenomena that appear in education, and to prepare a theoretical basis for explaining the phenomena. The importance of entrepreneurship education is emphasized to cultivate the ability to develop and provide products tailored to customers. The necessity of education leads to an increase in demand according to the situational awareness of the founders, and the quantitative increase in entrepreneurship education in the agri-food sector is a clear trend. Inevitably, the need for various discussions on systematic and effective entrepreneurship education is raised. For the study, an interview was conducted with preliminary or entrepreneur who have experienced entrepreneurship education in the agri-food sector. As a research method, I use Strauss & Corbin(1998)'s approach and analyze qualitative data using QSR's NVIVO 12 program. Through this study, it was found that contextual and systematic entrepreneurship education in the agri-food sector has the effect of strengthening competitiveness and strengthening sales. There is a need for follow-up management of trainees. Strengthening the competitiveness of start-ups is based on training professional manpower through education and linking regions with cities. Strengthening sales is based on product planning and market development. This study explores entrepreneurship education in the agri-food sector, which has not been actively conducted in the past. Exploratory analysis on the experiences of the founders of agri-food sector as education demanders has an important meaning for understanding the phenomenon of start-up education.

Effects of Citrus Peel Ethanol Extract on the Serum Lipid and Body Fat of High-fat-diet-fed Rats (고지방식이를 섭취한 흰쥐에서 진피 에탄올추출물이 혈청지질 및 체지방에 미치는 영향)

  • Park, Chang-Ho;Jung, Hee-Kyoung;Jeong, Yoo-Seok;Hong, Joo-Heon;Lee, Gee-Dong;Park, Chi-Deok
    • Food Science and Preservation
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    • v.18 no.4
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    • pp.567-574
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    • 2011
  • In this work, the major flavonoid content of citrus peel ethanol extract and the changes in the serum lipid and body fat of high-fat-diet-fed rats were examined. The subjects were divided into four groups: the normal, control, O1 (0.1% citrus peel ethanol extract), and O5 (0.5% citrus peel ethanol extract) groups. The experimental groups (O1 and O5) were fed a high-fat diet mixed with 0.1 and 0.5% citrus peel ethanol extract, respectively, for 10 weeks. The results of the analysis showed that the main ingredients of the flavonoid in the citrus peel ethanol extract (60 brix) were $38.21{\pm}1.37$ mg/g hesperidin and $15.02{\pm}0.48$ mg/g narirutin. With regard to the changes in the serum total-cholesterol level, compared with the control group's $79.1{\pm}4.6$ mg/dL, the serum total-cholesterol levels of the O1 and O5 groups were significantly lowered to $64.6{\pm}5.4$ and $59.5{\pm}4.7$ mg/dL, respectively. As for the changes in the LDL-cholesterol level, compared with the control group's $18.4{\pm}3.7$ mg/dL, the LDL-cholesterol levels of the O1 and O5 groups were significantly lowered to $13.0{\pm}3.6$ and $13.0{\pm}1.9$ mg/dL, respectively. For the changes in the serum triglyceride level, compared with the control group's $74.5{\pm}13.2$ mg/dL, the serum triglyceride level of the O5 group was significantly lowered to $48.6{\pm}11.2$ mg/dL. Finally, with regard to the changes in body fat, compared with the control group, the 05 group showed a significant decrease. In conclusion, it was observed that citrus peel ethanol extract was effective in lowering the total-cholesterol, LDL-cholesterol, and triglyceride levels of high-fat-diet-fed rats.

In Search of Corporate Growth and Scale-up in the Entrepreneurial Context: What Affects the Growth of Enterprise Value, the Pace of Growth, and the Effectiveness of Growth. (기업가적 컨텍스트에서 기업 성장과 스케일업 연구: 기업가치의 성장, 성장의 속도, 성장의 효과성에 영향을 미치는 요인)

  • Lee, Young-Dal;Oh, Soyoung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.4
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    • pp.25-58
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    • 2021
  • This study investigated the corporate growth with more emphasis on longitudinal characteristics, not the results of companies with relatively more emphasis on cross-sectional, in the 21st-century entrepreneurial context. As of the end of 2019, sampled 479 global unicorn companies, and 333 high-growth companies with revenue of more than $100 million among 5,000 private companies in the U.S. with a compound annual growth rate (CAGR) exceeding 15% for the past three years. They were examined with 3 perspectives in terms of corporate growth that 1) the growth of enterprise value, 2) the pace of growth, and 3) the effectiveness of growth. As a result of our study, the corporate growth of the perspective of creating enterprise value had a relatively higher relationship with the characteristics of industries and markets. The pace of growth was more fully explained by the characteristics of the industry and the market environment and the choice of strategies that make up a valid combination. In addition, growth in terms of the effectiveness of corporate performance was influenced by the choice of strategy, the characteristics of the industry and market environment, and its business age, the proxy variable of resource accumulation, comprehensively. This study through a sample based on companies with an enterprise value of more than $1 billion and annual revenue of more than $100 million can be a valid reference in terms of creating milestones and roadmaps for scale-up of early-stage startups, particularly in terms of practitioners' point of view. It also provides a critical reference for overcoming the limitations of mainstream theories of the 20th century and developing the theory of corporate growth that fits the 21st-century entrepreneurial context.

Effects of the Odor Abatement System in a Naturally Ventilated Growing Finishing Pig House (자연환기식 육성.비육돈사의 악취탈취장치 적용효과)

  • Lee, S.H.;Yun, N.K.;Kim, K.W.;Yum, S.H.;Cho, Y.H.
    • Journal of Animal Environmental Science
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    • v.14 no.1
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    • pp.31-38
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    • 2008
  • Ammonia gas is one of the malodorous gases from swine production facilities, such as manure storage tank, manure fermentation facilities, and livestock houses, etc. Ammonia gas from swine house is being emitted at relatively low concentrations throughout the year. Therefore, livestock facilities were continuously ventilated to supply fresh air for respiration of the animals internal the livestock facilities. The swine facilities need very high ventilation rate to control the inside environmental conditions. The deodorization system of the livestock facilities must be developed considering the ventilation rates. The odor abatement system was installed in order to improve the internal environment of the naturally ventilated growing-finishing pig house. The system which distributes the deodorized air into inner space of the swine house by using plastic duct was installed. Since the internal environment, effected by the operation of the odor abatement system, is monitored by closing the winch curtain installed on the side wall of the pig house, the experiment was practiced at the season when the internal environment becomes aggravated, winter. The effects on the improvement in the internal environment of swine house by operating the odor abatement system are as follows ; 1. By re-distributing the air which was deodorized by the odor abatement system installed in the pig house, the result showed that the concentration of ammonia gas is decreased approximately 33.3% compared with that before operating odor abatement system. 2. The effect on the pig house's ammonia gas reduction was found that the ventilation rate was less than $0.5m^3$/min head. The effect of the operation of the odor abatement system showed to be scarce when the ventilation rate increases because of the influx of external fresh air makes the quantity of diluted air more than those of the odor abatement system. 3. The perishment rate of the pigs which were brooded until slaughtering decreased about 3.8% by operating the odor abatement system in the growing-finishing pig house. Also, after operating the odor abatement system, the stinging of the eyes, suspension dust, etc were decreased when going into swine house for management.

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Hydrological Drought Assessment and Monitoring Based on Remote Sensing for Ungauged Areas (미계측 유역의 수문학적 가뭄 평가 및 감시를 위한 원격탐사의 활용)

  • Rhee, Jinyoung;Im, Jungho;Kim, Jongpil
    • Korean Journal of Remote Sensing
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    • v.30 no.4
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    • pp.525-536
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    • 2014
  • In this study, a method to assess and monitor hydrological drought using remote sensing was investigated for use in regions with limited observation data, and was applied to the Upper Namhangang basin in South Korea, which was seriously affected by the 2008-2009 drought. Drought information may be obtained more easily from meteorological data based on water balance than hydrological data that are hard to estimate. Air temperature data at 2 m above ground level (AGL) were estimated using remotely sensed data, evapotranspiration was estimated from the air temperature, and the correlations between precipitation minus evapotranspiration (P-PET) and streamflow percentiles were examined. Land Surface Temperature data with $1{\times}1km$ spatial resolution as well as Atmospheric Profile data with $5{\times}5km$ spatial resolution from MODIS sensor on board Aqua satellite were used to estimate monthly maximum and minimum air temperature in South Korea. Evapotranspiration was estimated from the maximum and minimum air temperature using the Hargreaves method and the estimates were compared to existing data of the University of Montana based on Penman-Monteith method showing smaller coefficient of determination values but smaller error values. Precipitation was obtained from TRMM monthly rainfall data, and the correlations of 1-, 3-, 6-, and 12-month P-PET percentiles with streamflow percentiles were analyzed for the Upper Namhan-gang basin in South Korea. The 1-month P-PET percentile during JJA (r = 0.89, tau = 0.71) and SON (r = 0.63, tau = 0.47) in the Upper Namhan-gang basin are highly correlated with the streamflow percentile with 95% confidence level. Since the effect of precipitation in the basin is especially high, the correlation between evapotranspiration percentile and streamflow percentile is positive. These results indicate that remote sensing-based P-PET estimates can be used for the assessment and monitoring of hydrological drought. The high spatial resolution estimates can be used in the decision-making process to minimize the adverse impacts of hydrological drought and to establish differentiated measures coping with drought.

Residue levels of phthalic acid esters (PAEs) and diethylhexyl adipate(DEHA) in various industrial wastewaters (업종별 산업폐수 중 프탈산에스테르와 디에틸헥실아디페이트의 잔류수준)

  • Kim, Hyesung;Park, Sangah;Lee, Hyeri;Lee, Jinseon;Lee, Suyeong;Kim, Jaehoon;Im, Jongkwon;Choi, Jongwoo;Lee, Wonseok
    • Analytical Science and Technology
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    • v.29 no.2
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    • pp.57-64
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    • 2016
  • Many phthalic acid esters (PAEs), including DMP, DEP, DBP, BBP, and DEHP, as well as DEHA are widely used as plasticizers in plastics. An analytical method was developed and used to analyze these compounds at 41 industrial facilities. The coefficient of determination (R2) for each constructed curve was higher than 0.98. The method detection limit (MDL) values were 0.4–0.7 μg/L for PAEs and 0.6 μg/L for DEHA. In addition, the recovery rate was shown to be 77.0–92.3%, while the relative standard deviation was shown to be in the range of 5.8-10.5%. DMP (n = 3), DEP (n = 2), DBP (n = 2), BBP (n = 2), and DEHA (n = 3) were detected in the range of 2.2-11.1% in the influent. DEHP was a predominant compound and was detected at > MDL in both the influent (n = 16, 35.6%) and the effluent (n = 4, 10.0%) at a high removal efficiency (92–100%). The highest levels of residue in industrial wastewater influent were 137.4 μg/L of DEHP at plastic products manufacturing facility, 12.5 μg/L of DEHA at a chemical manufacturing facility, and 14.0 μg/L of DEP at an electronics facility. The highest concentration of effluent was 12.5 μg/L of DEHP at a chemical manufacturing facility, which indicated that the effluent was below the allowable concentration (800 μg/L). Therefore, the levels of PAEs and DEHA that are discharged into nearby streams could not influence the health of the ecosystem.

Microbial Community of the Arctic Soil from the Glacier Foreland of Midtre Lovénbreen in Svalbard by Metagenome Analysis (북극 스발바르 군도 중앙로벤 빙하 해안 지역의 토양 시료 내 메타지놈 기반 미생물 군집분석)

  • Seok, Yoon Ji;Song, Eun-Ji;Cha, In-Tae;Lee, Hyunjin;Roh, Seong Woon;Jung, Ji Young;Lee, Yoo Kyung;Nam, Young-Do;Seo, Myung-Ji
    • Microbiology and Biotechnology Letters
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    • v.44 no.2
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    • pp.171-179
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    • 2016
  • Recent succession of soil microorganisms and vegetation has occurred in the glacier foreland, because of glacier thawing. In this study, whole microbial communities, including bacteria, archaea, and eukaryotes, from the glacier foreland of Midtre Lovénbreen in Svalbard were analyzed by metagenome sequencing, using the Ion Torrent Personal Genome Machine (PGM) platform. Soil samples were collected from two research sites (ML4 and ML7), with different exposure times, from the ice. A total of 2,798,108 and 1,691,859 reads were utilized for microbial community analysis based on the metagenomic sequences of ML4 and ML7, respectively. The relative abundance of microbial communities at the domain level showed a high proportion of bacteria (about 86−87%), whereas archaeal and eukaryotic communities were poorly represented by less than 1%. The remaining 12% of the sequences were found to be unclassified. Predominant bacterial groups included Proteobacteria (40.3% from ML4 and 43.3% from ML7) and Actinobacteria (22.9% and 24.9%). Major groups of Archaea included Euryarchaeota (84.4% and 81.1%), followed by Crenarchaeota (10.6% and 13.1%). In the case of eukaryotes, both ML4 and ML7 samples showed Ascomycota (33.8% and 45.0%) as the major group. These findings suggest that metagenome analysis using the Ion Torrent PGM platform could be suitably applied to analyze whole microbial community structures, providing a basis for assessing the relative importance of predominant groups of bacterial, archaeal, and eukaryotic microbial communities in the Arctic glacier foreland of Midtre Lovénbreen, with high resolution.

Analysis of dutasteride in human serum by LC-MS/MS (LC-MS/MS를 이용한 혈청 중 dutasteride 분석)

  • Nam, Hye-Seon;Nam, Kyong-Hee;Jung, Su-Hee;Lee, Jang-Woo;Kang, Jin-Yeong;Hong, Soon-Keun;Kim, Tae-Sung;Jung, Ki-Kyung;Kang, Tae-Seok;Yoon, Hae-Jung;Lee, Kwang-Ho;Rhee, Gyu-Seek
    • Analytical Science and Technology
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    • v.25 no.1
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    • pp.76-82
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    • 2012
  • The determination and confirmation of dutasteride in human serum was performed by a liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI/MS/MS). Beclomethasone as an internal standard (I.S.) was added to the serum and the mixed sample was pretreated by liquid-liquid extraction (LLE) with methyl tert-butyl ether (MTBE). The mass transitions of dutasteride and I.S. monitored in multiple reaction monitoring (MRM) were m/z 529.6${\rightarrow}$461.5 and m/z 409.3${\rightarrow}$391.2, respectively, and the retention times were 6.45 and 5.46 min, respectively. The calibration curve was linear in the concentration range of 0.5~30.0 ng/mL ($R^2$= 0.9999) and the limit of quantitation (LOQ) was found to be 0.5 ng/mL. The recovery of dutasteride was shown to be 66~72%. The intra-day assay precision and accuracy were in the range 3.5~5.5% and 85.7~89.9%, respectively, and the interday assay precision and accuracy were in the range 4.2~5.8% and 90.8~95.8%, respectively.

Biomass and distribution of Antarctic Krill, Euphausia superba, in the Northern part of the South Shetland Islands, Antarctic Ocean (남극 남쉐틀란드 군도 북부 해역의 크릴 분포 및 자원량)

  • KANG Donhyug;HWANG Doojin;KIM Suam
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.6
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    • pp.737-747
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    • 1999
  • To estimate biomass and distribution of the Antarctic krill (Euphausia superba), hydroacoustic survey was conducted on board of R/V Yuzhmorgeologiya, which was chartered by Korea Antarctic Research Program (KARP) group from 18 to 21 December 1998, in the northern part of the South Shetland Islands, Antarctic Ocean, The scientific echo sounder (towing body type) used was EK- 500 (SIMRAD, Norway) with echo integrator (BI-500) at 38 kHz frequency and recorded mean backscattering cross-section coefficient (SA) per 1 $mile^2$ of sea surface. Also, Bongo net sampling was carried out to determine the size of krill and CTD (Conductivity, Temperature and Depth) casting to understand physical structure. Water column was divided into 5 layers (22$\~$65 m, 65$\~$115 m, l15$\~$65 m, 165$\~$215 m and 215$\~$315 m) to know vertical distribution of krill biomass. The standard length of krill collected was between 30 mm and 51 mm, and adult krill had single mode (41 mm). Maximum horizontal length of krill patch was about 35 nautical mile and vertical thickness was about 275 m. High density of krill was appeared in frontal area between Circumpolar Deep Water (>$1^{\circ}C$) and very low temperature water mass (< $-0.5^{\circ}C$) that originate from Weddell Sea. According to the results calculated using target strength equation, krill density was totally higher in continental slope and open water areas than in coastal area. In the study area, krill seems to distribute in depth; density was low at first layer ($\={\rho}=17.0\;g/m^2$) and higher at fourth layer ($\={\rho}=40.19\;g/m^2$). The estimated krill biomass at total survey area and water column was about 2.77 million metric ion ($\={\rho}=151.0\;g/m^2$) and coefficient of valiance ( CV, $\%$) was 19.92. The proportions and biomass of krill biomass at each layer were as follows; layer 1 ($11.3\%$, 0.31 million metric ton, CV=16.24), layer 2 ($13.3\%$, 0.37 million metric ton, CV=34.91), layer 3 ($23.7\%$, 0.66 million metric ton, CV=41.5), layer 4 ($26.6\%$, 0.74 million metric ton, CV=27.84) and layer 5 ($25\%$, 0.69 million metric ton, CV= 26.83).

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