• Asian Journal of Turfgrass Science
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• v.19 no.2
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• pp.151-160
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• 2005

Research was initiated to investigate seasonal turf quality under a sand-based USGA soil system. USGA system 45 centimeters deep was built with rootzone layer, intermediate layer, and drainage layer. Six turfgrass entries were comprised of 3 blends and 3 mixtures from cool-season grasses (CSG). Turfgrass quality ratings were best in spring and fall, especially early May to early July and late August to early November. Kentucky bluegrass(KB) consistently produced the greatest quality, while perennial ryegrass (PR) the poorest. Intermediate turf quality between KB and PR was observed with tall fescue (TF). Among CSG mixtures it increased with KB but decreased with PR. There were considerable variations in summer turf performance. No summer drought injury was found in KB and TF. However, PR showed poor performance through summer as compared with other CSG. Results demonstrate that KB was the best and PR the worst among CSG grown in a sand-based USCA soil system.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.461-468
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• 2012

This study was conducted to study the seasonal changes of relative water relations parameters by pressure-volume curves of Korean mistletoe (Viscum album var. coloratum) leaves for understanding ecological characteristics. In growing season, the osmotic potentials at full turgor (${\Psi}_o^{sat}$) and at incipient plasmolysis (${\Psi}_o^{tlp}$) decreased, while increased the maximum bulk elastic modulus of the cell wall ($E_{max}$) and relavive water content ($RWC^{tlp}$). Korean mistletoe in Quercus variabilis and Korean mistletoe in Quercus mongolica in November showed best maximum perssure potential (${\Psi}_{P,\;max}$). Pressure potential (${\Psi}_P$) and water potential (${\Psi}_L$) in Korean mistletoe in Quercus variabilis were rapidly decreased with decreasing of relative water content. The values of $RWC^{tlp}$ in November were all above 84% showing that the function of osmoregulation is somewhat better, and symplastic water content (Vo/DW) and maximum water content (Vt/DW) were variable seasonally. Thus, responses to water relations of Korean mistletoe in Quercus variabilis and Korean mistletoe in Quercus mongolica such as ${\Psi}_o^{sat},\;{\Psi}_o^{tlp},\;E_{max},\;{\Psi}_{P,\;max},\;RWC^{tlp}$ showed increaing drought tolerance with increasing of leaf aging.

• Korean Journal of Plant Resources
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• v.23 no.4
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• pp.374-378
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• 2010

Determining plant moisture characteristics is an essential study not only for cultivation, but also for ex-situ conservation. In this study, employing pressure-volume curve we examined moisture characteristics of Rhododendron micranthum, known as rare plant, with the aim of its ex-situ conservation. Several individuals growing in Mt. Worak, Youngwol-gun Yeonha-ri and Bongwa-gun Seokpo-ri were selected for this study, from which we collected leaves. The original bulk osmotic pressure at maximum turgor(${{\Psi}_o}^{sat}$)was -1.5 MPa in those of Mt. Worak and Seokpo-ri, which is somewhat lower than that of Yeonha-ri(-1.2 MPa). It appeared that the osmotic pressure at incipient plasmolysis(${{\Psi}_o}^{tlp}$) of leaves collected in both Mt. Worak and Seokpo-ri were -1.29 MPa, and -1.26 MPa, respectively, which are lower than that of Yeonha-ri(-1.02MPa). Maximum bulk modulus of elasticity($E_{max}$) was 14.0 MPa, 8.67 MPa in leaves collected from both Seokpo-ri and Mt. Worak, respectively, those value of which were approximately 3 times higher than that of Yeonha-ri(4.00 MPa). The values of $RWC_{tlp}$(Relative water content at incipient plasmolysis) of leaves collected in three areas, were roughly 83%, suggesting that Rhododendron micranthum has relatively high capability of containing water. Our finding on moisture characteristics of Rhododendron micranthum is similar to those of other Rhododendron spp. We suggest that individuals growing in both Worak and Seokpo-ri, are preferable to those in Yeonha-ri for ex-situ transplantation since those individuals are found to have better drought resistance.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1978.06a
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• pp.4.3-5
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• 1978

The foreign bodies in air way require the emergent managements in the otolaryngolagic field, and if the diagnosis and treatment were delayed, unexperted catastrophic situations may occur. The authors had analysed the airway foreign bodies of 50 cases which had been ventilating bronchoscopy. 1. In sex distribution, male to female ratio was 2.8 : 1. 2. In the age incidence, 58% were 1∼5 yrs. 3. Frequent symptoms, were coughing (68%), dyspnea (52%) and cyanosis (18%) in the oder. 4. The significant foreign body histories were noticed in 33 cases (66%). The initial misdignosis were 28%, and af which 57.1% were URI 5. In auscultation, decreased breathing sounds were noticed in 46%, wheezing were 24% and 26% were with in normal limit. 6, In duration af lodgement, 68% were removed within 24 hours. 7. Tracheostomy were performed in 24%, and foreign bodies were removed by ventilating bronchoscope in 72%. 8. The foreign bodies were vegetable (46%), metal (28%), plastic (18%) and fish bone (8%). 9. The prevalent site of foreign body were right main bronchus, left main bronchus, and trachea in the order mentioned.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.730-735
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• 2013

This study compared the nutritional components (proximate components, fatty acids, amino acids, minerals and vitamins) between genetically modified (GM) drought-tolerant rice and a parental rice cultivar (Ilmibyeo) as a non-GM control. Both GM and non-GM rices were grown and harvested in two different locations, Gunwi and Suweon in Korea. Proximate components (moisture, starch, protein, lipid, and ash contents) were similar between the drought-tolerant GM rice and the conventional non-GM rice. There were no significant differences between the GM and non-GM rice in most of their nutrient compositions, despite minor locational differences of some amino acids and minerals. These results indicate that transgenic rice with a genetically improved resistance to drought is equivalent to the parental rice cultivar without major changes in its chemical contents.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.159-163
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• 2013

The purpose of this study is to observe the growth habit and investigate a possibility of cultivating the GM rice (CaMsrB2-8) as a rice cultivar having drought resistance. Germination viability test showed that there was no significant difference between the drought-resistant GM(CaMsrB2-8) and non-GM (Ilmi) rice which was the parent variety at the GM rice. All the seeds of CaMsrB2-8 and Ilmi germinated after 6 days. Viviparous germination was not found in CaMsrB2-8 and Ilmi that was grown in greenhouse at $23{\pm}2^{\circ}C$ with water spraying for 40 days. Ratooning of CaMsrB2-8 and Ilmi was observed in 7-14 days and found uniform in field condition. CaMsrB2-8 seemed to grow faster than Ilmi. But CaMsrB2-8 and Ilmi were similar in 14-21 days. Both CaMsrB2-8 and Ilmi showed low seed shattering and more than 90% grains were ripened. All the seeds scattered in the paddy soil surface were not germinated after passing the winter. This study suggests that the drought-resistant GM rice was not significantly different with the parent variety of Ilmi in many agronomic characteristics such as wildness traits.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.172-180
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• 2002

Leaf litter breakdown rates of the Phragmites australis, Zizania latifolia and Typha angustifolia were determined at the lower Nakdong River from Nov. 1998 to Sept. 1999. The relationship between leaf litter breakdown of three and abundance of aquatic invertebrates was investigated. Aquatic invertebrates collected in the litterbags were 11 family, 11 species (mean density: $222\;ind./m^2$ , n = 792), and Chironomidae was dominant. Mean density of Chironomidae in the litterbags were different according to the aquatic plant species: Z. latifolia ($180\;ind./m^2$, n = 264) T. angustifolia ($187\;ind./m^2$, n = 264) P. australis ($95\;ind./m^2$, n = 264). The breakdown of Z. latifolia was the shortest, and that of T. angustifolia was shorter than P. australis. Overall, the breakdown rate at floating layer was faster than that of submerged layer in all of three species and differences of the breakdown rate between open bags and closed three species and differences of the breakdown rate between open bags and closed bags were not found.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.2
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• pp.201-207
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• 2011

Purpose: This study was to find out the influence on eyes of indoor air quality in college students taking course, such as Sick-building syndrome symptoms and effects on the eye in new-built university buildings. Methods: We selected a new building in a university located in Metro Seoul and college students in a department for the study. The number of total participants was 33, to whom questionnaire surveys were conducted in advance to check individual traits (gender, age, whether to smoke, whether to wear contact lenses, or whether to drink). The first questionnaire surveys and checking of ocular symptoms to first indoor hazardous materials were conducted in October and two months later the second surveys and checking were carried out in December. The indoor air quality was measured when conducting the first questionnaire surveys and the second questionnaire surveys; especially measurements of gaseous materials such as aldehydes and VOCs in the indoor air were conducted. Results: Indoor air quality of the new building was as follows: formaldehyde level was 22.90 ${\mu}g/m^3$ in the first measurement and 16.79 ${\mu}g/m^3$ in the second measurement. In addition, most materials showed higher value in the first measurement. The level of TVOC was statistically significant (p<0.05) decreased on 448.54 ${\mu}g/m^3$ in the first and 62.55 ${\mu}g/m^3$ in the second. In clinical assessments to check ocular symptoms caused by eye irritations, dry eye syndrome was found in the first and second exposures. When comparing the first and second assessments, dry eyes deteriorated in the morning of the second attempt compared to the first one. Conclusions: In the survey of ocular symptoms and the measurement of indoor air quality, the level of formaldehyde was measured higher in the second attempt than the first; thus, it was confirmed the influence of indoor air quality in a new building upon ocular symptoms of occupants.

• Journal of Life Science
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• v.29 no.6
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• pp.653-661
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• 2019

The first small interfering RNA (siRNA) therapeutics have recently been approved by the Food and Drug Administration in the U.S., and the demand for a new RNA therapeutics bioanalysis method-which is essential for pharmacokinetics, including the absorption, distribution, metabolism, and excretion of siRNA therapeutics-is rapidly increasing. The stem-loop real-time qPCR (RT-qPCR) assay is a useful molecular technique for the identification and quantification of small RNA (e.g., micro RNA and siRNA) and can be applied for the bioanalysis of siRNA therapeutics. When the anti-HPV E6/E7 siRNA therapeutic was used in preclinical trials, the established stem-loop RT-qPCR assay was validated. The limit of detection was sensitive up to 10 fM and the lower limit of quantification up to 100 fM. In fact, the reliability of the established test method was further validated in three intra assays. Here, the correlation coefficient of $R^2$>0.99, the slope of -3.10 ~ -3.40, and the recovery rate within ${\pm}20%$ of the siRNA standard curve confirm its excellent robustness. Finally, the circulation profiles of siRNAs were demonstrated in rat serum, and the pharmacokinetic properties of the anti-HPV E6/E7 siRNA therapeutic were characterized using a stem-loop RT-qPCR assay. Therefore, the stemloop RT-qPCR assay enables accurate, precise, and sensitive siRNA duplex quantification and is suitable for the quantification of small RNA therapeutics using small volumes of biological samples.

• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.36-46
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• 1988

Twelve soybean cultivars were cultivated in the 1/2,000a. Wagner pots with irrigation and without irrigation for 30 days after flowering, and the differences of plant growth and bean yield among cultivars were compared. And to investigate the varietal differences in the rate of photosynthesis under different relative humidity, 6soybean cultivars were cultivated in 1/2,000a. Wagner pot and the rate of photosynthesis of each soybean cultivar at flowering time was measured under the relative humidity of 80, 70, 60, 50 and 40%. The results obtained are summarized as follows; 1. The days to maturity of the soybean cultivars were shortened by non-irrigation treatment. The response of the maturing dates to non-irrigation was significantly different among the soybean cultivars. The days for maturing of Paldal, Danyeob and Eundaedu were delayed 2 days but those of Jangbaek and Tamahomare were delayed about 7 to 8 days under non-irrigation treatment. 2. The stem length, stem diameter, number of nodes of the mainstem, number of branches and number of branch nodes of all soybean cultivars were decreased by non-irrigation treatment. The number of branches and the number of branch nodes were especially severely influenced by non-irrigation treatment. 3. The number of pods per plant and the number of perfect pods was significantly reduced by non-irrigation treatment but the number of imperfect pods was increased. The non-irrigation treatment reduced the number of pods per plant by 58.0% and the ratio of the number of the perfect pods per plant by 46.6% relative to the ordinary cultivation with irrigation. 4. The grain yield of all cultivars was significantly reduced by the non-irrigation treatment, and average grain yield of soybean cultivars cultivated under non-irrigation treatment was 35.9% of that of soybean cultivars cultivated with irrigation. The influence of non-irrigation treatment was lowest in Paldal and significantly high in Tamahomare and Jangbaek. 5. The rate of photosynthesis of soybean leaves was significantly different among cultivars and was also influenced by relative humidity. Ratio of the photosynthetic amount of soybean leaves at 40% RH to the maximum photosynthesis at optimal humidity was 97.2% in Paldal, 96.4% in Danyeob and 88.8% in Baekun. 6. At 40% relative air humidity, highly significant correlations were found among the photosynthesis rate, the amount of transpiration and the respiration rate.