• Korean Journal of Poultry Science
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• v.33 no.2
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• pp.97-103
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• 2006

Telomeres are essential for chromosome stability and are related with cell senescence, apoptosis and cancer. Even though telomere length and telomerase activity have been studied extensively, very little is known to analyze the telomere dynamics in chicken cells. This study was carried out to analyze the telomere distribution and telomerase activity of Korean Native Chicken cells along with aging. The cells were collected from brain, heart, liver, kidney and germinal tissues during physiological stages. Telomere distribution was analyzed by Quantitative-Fluorescence in situ Hybridization (Q-FISH) techniques using the chicken telomeric DNA probe. Telomerase activity was performed by Telomeric Repeat Amplification Protocol (TRAP) assay. In results, the telomeres of chicken were found at the ends of all chromosomes with the interstitial telomeres on chromosomes 1, 2 and 3. The amount of telomeres on chicken cells was decreased along with aging in most tissues. Furthermore, the telomere quantity was significantly different among tissues. The relative amount of telomeres in proliferous cells such as testis cells had much more than those of liver, brain, heart, blood and kidney cells. The telomerase activity was down-regulated in cells of brain, heart and liver tissues. Whereas gonadal cells showed a constitutive activity of telomerase during all stage of life. In conclusions, the telomere quantity and telomerase activity in chicken are closely relate to cell proliferation and tissue specificity during developmental stages and aging. There is also closely correlated between the amounts of telomeric DNA and telomerase activity in chicken tissues.

• Korea journal of population studies
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• v.26 no.1
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• pp.1-30
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• 2003

This paper attempts to explore the effects of ecological and socioeconomic factors on the level of mortality and the changing trends of such effects during the period of 1990∼2000. For this purpose the population census data and micro-data from the vital statistics for years 1990, 1995 and 2000 were used. As indicators of mortality, the crude death rate(CDR), the standardized death rate(SDR) and the longevity rate were calculated for 170 'Si' s and 'Gun's. Using GIS, this paper first presents the mortality and longevity maps for years 1990, 1995 and 2000. Then ANOVA and regression analyses are carried out in an effort to generalize the effects of ecological and socioeconomic factors on the CDR, the SDR and the longevity rate. When the mortality and longevity maps are examined, three indices of mortality are found to be markedly high in the southwest coastal regions of Cholla-Nam-Do. By contrast, Seoul and Pusan metropolitan areas show substantially low level of mortality and longevity in these indices. It is also found that the regional differentials in the SDR and the longevity rate show a trend of becoming smaller after 1990. The research, however, does not find any linear relationship between the SDR and the longevity rate. The causal mechanisms of the two indices are found to be different. The results of the ANOVA and the regression analysis reveal that the locational factors of both mountainous and farming regions tend to increase the CDR and SDR while both coastal and farming regions disclose a tendency of increasing the longevity rate. The level of statistical significance of these analytical results is found to be weaker when socioeconomic factors such as education, income, marital status, availability of medical care, and sanitary conditions of the region are taken into account. The regional differentials in the mortality level seem to have a clear relationship not only with the socioeconomic factors but also with the age structure influenced by the age selectivity of migration during the past 40 years.

• Korean Journal of Environmental Agriculture
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• v.22 no.4
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• pp.246-250
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• 2003

In order to preserve the soundness of agro-ecosystem and products safety in agriculture, this study was evaluated environmental impact in relation to the INM (Integrated Nutrient Management) and IPM (Integrated Pest Management) at paddy fields at Ok-Chun and Yang-Pyung region. By introduction of INM with the application of BB(bulk-blanded) fertilizer based on soil analysis and IPM, the application rate of fertilizer was reduced to about $28.6{\sim}39.4%$ and the yield of brown rice was increased to about $3{\sim}10%$ compared to conventional practices. The concentrations of COD, $NH_4-N$, and $NO_3-N$ in irrigation water flowed to the environmental-friendly agriculture practices were 15.0, 0.67, and 1.39 mg/L, respectively. The concentrations of COD, $NH_4-N$, and $NO_3-N$ from paddy fields in drainage water were 12.4, 0.29, and 2.42 mg/L, respectively. The total number of the freshwater invertebrates was higher in field treated with fertilization by prescription with soil testing. Also, the population density of aquatic insects was higher than the other fields at both demonstration villages. In conclusion, it was possible to reduce the amount of fertilizer and agricultural chemicals application, and increase the yield of rice by application of the environmental-friendly agriculture practices.

• Journal of Technology Innovation
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• v.25 no.2
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• pp.89-125
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• 2017

Complex product systems (CoPs) is a engineering-intensive products with high-ended design technology, which are closely linked with national economic growth and development of social infrastructures. Accordingly, in order to understand the technological evolution of CoPs, it is necessary to identify the macro-environmental drivers surrounding the CoPs and their impact on the technological evolution of the CoPS. Therefore, we investigate the effect of policy, economic and social drivers on the technological evolution of CoPS by implementing the longitudinal case study on nuclear power plant during the periods between 1950 and 2010s. Based on the analysis of various sources of secondary data and primary data through interviews, we found that the technological evolution of nuclear power plant is progressed as "Phase 1: Application research for peaceful utilization of nuclear energy" between 1950s and 1960s, "Phase 2: The first renaissance of nuclear energy" during 1970s, "Phase 3: Enhancement of safety and the catch-up of latecomers in nuclear energy" between 1990s and 2000s, and "Phase 4: Top prioritization of safety and the development of next generation reactors for the second renaissance of nuclear energy" since 2010s. We also found that various kinds of policy, economic and social drivers, such as energy policy, investment in technology development, economic growth and energy demand, social acceptability and environmental concern, have affected the technology evolution of nuclear power plant at each phase. We emphasize the role of macroenvironmental drivers in the technological evolution of CoPS. We also suggest that countries that endeavor to develop CoPs need to utilize those drivers for enhancing competitiveness and sustaining leadership.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.271-278
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• 1995

The objective of the present study was to investigate the inhibitory effect of physiologically pulsatile pattern of testosterone(T) on luteinizing hormone(LH) in wethers. To do this, 3 separate experiments were conducted. Infusion rates and patterns needed to produce normal T secretory profiles found in intact rams were established in Experiment 1, the time-course of the suppressive effect of T on circulating LH concentrations was determined in Experiment 2, and the effectiveness of a pulsatile versus a constant pattern of T to suppress LH secretion in wethers was compared in Experiment 3. In Experiment 1, three different doses(25, 50 or $100{\mu}g$) of T were injected intravenously to animals to do pharmacokinetic analysis of T. Elimination rate constant, volume of distribution, and total body clearance of T averaged $0.18min^{-1}$, 0.531/kg BW, and 0.091/min/ kg BW, respectively. In Experiment 2, three different doses(192,384, or $768{\mu}g/kg/24h$) of T were infused at 4h intervals for 3 days into animals to evaluate the time course of the inhibitory effect of T on mean LH concentration. As duration of T infusion increased, mean LH concentrations gradually reduced. Mean LH concentrations were significantly lower at day 2 or day 3 than at day 0. However, mean LH concentrations did not differ between day 0 and day 1 or between day 2 and day 3. In Experiment 3, animals were subjected to two different intravenous infusion regimens for 3 days: constant T($768{\mu}g/kg/24h$) and pulsatile(one pulse every 4h) T($768{\mu}g/kg24h$). Blood samples were collected at 10-min intervals for 4h both prior to infusion and during the last 4h of the infusion. Mean LH was more suppressed(p=0.045) by constant T than by pulsatile T. LH pulse amplitude was not affected by constant T or pulsatile T. LH interpulse interval was increased more(p=0.034) by constant T than pulsatile T.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1255-1262
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• 2013

The objective of this study was to analyze the general and functional components of various soybeans, used for producing soy sauce, tofu, bean sprouts, and for cooking with rice. The moisture, crude protein, crude fat, and ash content of soybeans were in the ranges of 5.50~6.16%, 38.49~41.08%, 14.89~21.89%, and 4.89~5.86%, respectively. Mineral and functional components varied by sample and showed no relationship with usage type. Somyeong for bean sprouts had the highest level of Ca (406.36 mg/100 g), and Sinpaldal for soy sauce and tofu had the highest level of Mg (247.79 mg/100 g). However, Jinpum No. 2 for soy sauce and tofu had the lowest level of Ca (199.51 mg/100 g), and Seonhuk had the lowest level of Mg (90.03 mg/100 g) among the soybeans tested. The isoflavone content in soybeans was in the range of 97.54~402.00 mg/100 g. Somyeong for bean sprouts had the highest level and Seonheuk for cooking with rice had the lowest level. Total oligosaccharides were in the range of $5,838.52{\sim}9,345.90{\mu}g/100g$. Sucrose content was approximately 50% of total oligosaccharides in all samples. Raffinose content was $516.28{\sim}806.95{\mu}g/100g$, and stachyose content was $2,047.13{\sim}3,454.10{\mu}g/100g$. Phytosterols including bracassisterol, campesterol, stigmasterol, and ${\beta}$-sitosterol ranged from 19.25~35.34 mg/100 g. ${\beta}$-sitosterol represented 50% of total phytosterols in almost all samples, followed by campesterol, stigmasterol and bracassisterol. The phytic acid content in soybeans tested was around 2%, except for Sinpaldal No. 2 and Jinpum No. 2 at 0.86% and 1.65%, respectively. The dietary fiber of soybeans was in the ranges of 24.20%~29.20%.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.2
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• pp.38-46
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• 2013

The goal of vocational school is to provide students with basic skills and help develop them to have satisfactory careers. With the knowledge they have learned, it helps them to find their interests and aptitudes when they graduate. The government is putting a lot of effort into clarifying the goal accomplishment and the vision proposals of vocational schools, and the structure-oriented guidance controlled by the government is thought to be very influential to the social structure and individual perceptions. Social stereotypes(discrimination) and perceptions that can be the core of a social structure need to be transformed for people to be fulfilled in their careers in the upcoming advanced Korean society. The important solution is to form correct values and a system of career selection which can ensure a stable future for students. Therefore, to carry out research regarding training human resources in terms of students from vocational schools' landscape architecture majors in an approaching method with a new perspective, we analyzed education plans from vocational schools in 11 regions, textbooks used in common, governmental publications regarding career education policies of vocational schools and questionnaires from students who are majoring in landscape architecture at vocational schools. As a result, we were able to find out the types and the frequencies of career-occupation education at each school through analysis of education plans and the necessity to control the amount and the level of the contents for high school students to have careers in analyzing textbooks. In addition, in Ministry of Education, Science and Technology's analyzing career education policies of vocational schools, we figured out the government's policies and directions of training. From the questionnaires from students majoring in landscape architecture, we were able to compare and analyze the satisfaction level of students on career education(education plans), textbooks, governmental career policies and career selection.

• Korean Journal of Ecology and Environment
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• v.48 no.4
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• pp.212-218
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• 2015

In South Korea, various nature-like fishways recently been installed for use by a wide variety of fish species. However, limited attempts have been made to monitor the fish utilization. The present study was conducted to ascertain the frequencies and patterns of utilization of the fishway installed at Beakjae Weir. We collected fish species that use the fishway by installing a fyke net at the exit of the fishway at least once a month from April 2013 to October 2013. Additionally, in order to identify all fish species that can potentially use the fishway, we investigated the fish fauna downstream to Beakjae Weir (mainstream of the Geum River). We found that 10 species belonging to 2 families used the fishway; this accounted for 64% of the total species inhabiting the mainstream. The species that used the fishway most frequently were Microphysogobio jeoni, followed by Squaliobarbus curriculus and Opsariichthys uncirostris amurensis. The highest number of fish using the fishway was observed in August, which was positively correlated with the water temperature (Spearman rank correlation, $r_s$=0.743, P=0.035). The sizes of the fish using the fishway varied widely, with the total body length ranging from 39 mm to 550 mm. Analysis of the time-dependent utilization frequency revealed that most fish used the fishway during the night (20:00~08:00). Compared to other fishways installed along the Geum River, the fishway installed at Beakjae Weir was used by fewer species and fish. This may be attributed to the structural inadequacy of the fishway, thereby resulting in a low attraction efficiency. Therefore, measures should be adopted to enhance the fishway attraction and passage efficiency. The results of this study can be used to ensure efficient operation and management of the Beakjae Weir fishway as well as serve as basic data for developing and building nature-like fishways tailored to Korean situations.

• Journal of Veterinary Clinics
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• v.32 no.2
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• pp.168-173
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• 2015

This study estimated the degree of uterine inflammation and resumption of ovarian cyclicity in postpartum dairy cows. In addition, the prevalence of health problems during calving and the postpartum period was investigated. A total of 224 Holstein dairy cows from four dairy farms in Chungcheong Province were used for the study. Uterine discharge was scored on a 0 to 5 rank scale (metricheck score) using a metricheck instrument from 1 to 8 weeks postpartum and uterine cytology (neutrophil level) was examined at 4, 6 and 8 weeks postpartum to evaluate uterine inflammation. Resumption of ovarian cyclicity was evaluated based on progesterone analysis (${\geq}1ng/mL$) at 4, 6 and 8 weeks postpartum. Postpartum disorders were diagnosed by veterinarians in the research team. The metricheck score decreased linearly (p < 0.0001) from weeks 1 ($3.4{\pm}0.1$) to 4 ($2.0{\pm}0.1$) postpartum, and then remained at that level through week 8 postpartum ($1.6{\pm}0.1$, p > 0.05). The neutrophil levels determined by uterine cytology assays also decreased (p < 0.0001) from week 4 ($22.3{\pm}1.8%$) to 6 ($12.1{\pm}1.4%$) postpartum, and then remained at that level through week 8 postpartum ($9.2{\pm}1.4%$, p > 0.05). The proportion of cows exhibiting the ovarian cyclicity increased linearly (p < 0.0001) from weeks 2 (12.1%) to 8 (74.3%) postpartum. The prevalence of dystocia and retained placenta were 20.5% and 30.4%, respectively. The prevalence of ketosis, milk fever, abomasal displacement, septicemic metritis, endometritis, subclinical endometritis, pyometra, and ovarian cysts were 18.8%, 3.6%, 4.0%, 36.2%, 29.5%, 17.0%, 4.5%, and 14.7%, respectively. The prevalence of digestive problems and mastitis were 5.4% and 9.6%, respectively. The prevalence of culling and death were 4.0% and 3.6%, respectively. The prevalence of dystocia, retained placenta, septicemic metritis, endometritis, ovarian cysts, digestive problems, mastitis, and culling differed among farms (p < 0.05 to 0.01). In conclusion, proper examinations for uterine inflammation and ovarian cyclicity during 4 to 8 weeks postpartum are useful clinical tools to maintain herd reproductive health. Dystocia, retained placenta, septicemic metritis, and endometritis were predominant disorders in dairy cows of the survey area.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.4
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• pp.29-41
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• 2015

Abandoned paddy field provides an excellent opportunity to improve the species diversity and habitat quality. Ecological characteristic on the changing of plant communities at different seral stages is a major basis data for ecological restoration. In this study, we investigated changes of the species composition and community indices on the plant community associated with abandonment of cultivated rice paddies. The ecological stability of the habitat was evaluated by using eco-floristic characters(Di; Disturbance index, AUI; Actual urbanization index). Survey sites were grouped into six stages(stageI (${\leq}3years$), stageII(3-5years), stageIII(5-7years), stageIV(7-10years), stageV(10-15years), stageVI(${\geq}20years$). Vegetation investigation was done from May 2009 to October 2012 and carried out phytosociological approach. The total flora were summarized as 176 taxa including 58 families, 127 genera, 157 species, 3 subspecies, 15 varieties and 1 forms. At each of successional stages, 64 taxa in stage I, 34 taxa in stage II, 84 taxa in stage III, 83 taxa in stage IV, 92 taxa in stage V, 23 taxa in stage VI were identified. Of the occurrence plants, the species with the highest r-NCD value were Alopecurus aequalis, Juncus effuusus var. decipiens, Persicaria thunbergii, Artemisia princeps, Salix koreensis and Alnus japonica at each stages. Herbaceous annual plants were dominated in the early stage, but its r-NCD value declined in the middle stage and the late stage. On the other hand, herbaceous perennial plants and Persicaria thunbergii, annual hydrophytes, increases in the middle stage. Woody plant and herbaceous plant which appeared in the forest edge increases in the late stage. Community indices correlate with successional stages. Richness and diversity index increase along the successional gradient. But dominance index decrease along the successional gradient. Evenness index was correlated with lower. In the ecological stability analysis of the habitat that evaluated by eco-floristic characters, stage I was the most unstable habitat. And the stability of the habitat has improved according to the successional stage.