• Applied Microscopy
• /
• v.38 no.4
• /
• pp.307-314
• /
• 2008

Hydrophytes such as Spirodela polyrhiza form dormant turions to withstand cold winters. The turion is an anatomically distinct structure from which a vegetative frond arises later during germination. The turions sink to the bottom of the pond when temperatures drop and remain there throughout the winter. In the spring, they float to the surface and germinate into a new frond from the turion primordium. Unlike fronds, turions are known to possess small aerenchyma, starch grains, and relatively dense cytoplasm. These features allow the turions to survive the cold winter season at the bottom of the pond. Spirodela polyrhiza has been investigated previously to a great extent, especially in its physiological, biochemical and ecological attributes. However, a little is known about the structural features of the frond and turion during turion development. Thus, the aim of the present study was to reveal the structural characteristics of the frond and turion with regard to tissue differentiation, aerenchyma development, starch distribution, and ultrastructure, with the use of electron microscopy. A moderate degree of mesophyll tissue differentiation was found in the frond, whereas the turion did not exhibit such differentiation. Within the frond tissue, approximately $37{\sim}45%$ of the cellular volume was occupied by a large aerenchyma, but only $9{\sim}15%$ was taken up by the aerenchyma in the turion. The turion cells, especially those of the turion primordium, were derived from frond cells, and contained cytoplasm. Their cytoplasm was densely packed with plastids, mitochondria, endoplasmic reticulum, Golgi bodies, and microtubules. Plasmodesmata were also well developed within these cells. The most striking feature observed was the distribution of starch grains within the plastids of turion cells. Before the turion sank to the bottom of the pond, a considerable amount of starch accumulated in the plastid stroma. The starch grains dissolved when temperatures rose in the spring, and this promptly provided the nutrients which the primordium needed for turion germination. The turion therefore, was an appropriate dormant structure for free-floating, reduced hydrophytes like Spirodela polyhriza due to its small aerenchyma and large starch grains that aided in the purpose of sinking below the surface of the water to survive cold winters. The new fronds that arose from such turions grew rapidly in the spring, beginning the new life cycle.

• Korean Journal of Food Science and Technology
• /
• v.35 no.3
• /
• pp.510-518
• /
• 2003

Protective effects of natural components including genistein (4',5,7-trihydroxyisoflavone) from Glycine max MERRILL on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. Genistein $(10{\sim}100\;{\mu}m)$ suppressed photohemolysis in a concentration-dependent manner, and was more effective than the lipid peroxidation chain blocker, ${\alpha}$-tocopherol (Vit. E). Glycoside of genistein, genistin, the water-soluble antioxidant, L-ascorbate, and the iron chelator, myo-inositol hexaphosphoric acid dodecasodium salt (sodium phytate) did not exhibit protective effect against photohemolysis. L-Ascorbate and sodium phytate stimulated photohemolysis at high concentration $(500\;{\mu}m)$. ${\alpha}$-Carotene 3,3'-diol (lutein), a singlet oxygen $(^1O_2)$ quencher, exhibited pronounced protective effect, an indication that $^1O_2$ is important in photohemolysis sensitized by rose-bengal. Reactive oxygen scavenging activities $(OSC_{50})$ of natural antioxidants including genistein on reactive oxygen species (ROS) generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescence assay were in the order of sodium phytate > L-ascorbate > ${\alpha}$-tocopherol > genistein > genistin. $OSC_{50}$ value of genistein, genistin, ${\alpha}$-tocopherol, L-ascorbate, and sodium phytate were 41.0, 109.0, 9.0, 5.2, and $0.56{\mu}m$ respectively. The order of free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity $(FSC_{50})$ was L-ascorbate > ${\alpha}$-tocopherol > genistein > genistin. These results indicate that genistein can function as an antioxidant in biological systems, particularly skin exposed to solar UV radiation by scavenging $^1O_2$ and other ROS, and to protect cellular membranes against ROS.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.4 no.3_4
• /
• pp.113-120
• /
• 1971

In 1971, about 150,000 fingerlings of grass and silver carps were produced and distributed from the Fishculture Laboratory of Pusan fisheries College. The adults Were those transplanted from Japan in 1963. Findings during the process of this production are summarized as following : 1. Brood fish must be handled with a great care during the catching, hormone injection and maturity inspection so as the fish are not injured, otherwise, the eggs would not mature perfectly. Scale fall also affects significantly. 2. The amount of pituitary to be injected is preferable to be 2 to 3 times or more in donor's body weight to obtain good results. 3. The eggs should be spawned or stripped and inseminated as soon as mature. If the spawning is delayed the eggs become overmature and the hatching rate decreases significantly. 4. The water once used for the incubation of eggs should not be reused. The eggs under hatching process were melted away when water once used for incubation was reused. 5. A great care must be paid to keep water in quality when the net cage culture system is employed for raising fry or early fingerlings of Chinese carps. The best method to keep water in quality is to supply water in the cage continuously through a pipe or hose. 6. Heavy outbreaks of Spirogyra occured when clear well water was supplied into the cage, and a great number of fry or fingerlings were trapped or entangled resulting in a significant decrease of fish under rearing. It was prevented when moderately bloom-ed pond water was supplied into the cage. 7. Silver carp fry are usually captured and transported in the cool season because they can not be handled in the warm season owing to a high mortality, but cage cultured small size fingerlings ranging from 1.5 to 2 cm in total length are easily handled and transported even in the hot summer season, thus it enables the fish farmers to start growing them one season earlier.

• Journal of the East Asian Society of Dietary Life
• /
• v.12 no.2
• /
• pp.91-99
• /
• 2002

This study was carried out to develop a diabetic-oriented convenience flood using 7 medicinal plants (Schisandra chinensis, Coix lachryma-jobi, Dioscorea batatas, Ophipogon japonicus, Lyicium chinense, Houttuynia cordata, Polygonatum sibiricum) and chicken. Portion size was 310g, total calorie was 551.6 kcal and carbohydrate, lipid and protein were consisted of 53.0%, 20.9% and 26.1%, respectively. Calcium, zinc and iron content were 268.9mg, 5.4mg and 6.1mg, respectively. Crude fiber content was 22.9g. In sensory evaluation, the scores of taste, color, texture and overall acceptability were higher than normal diabetic meal. Hypoglycemic effect of the device meal for diabetic persons was excellent compared to that of normal diabetic meal. The above results indicate that the 7 medicinal plants can be used as functional ingredients fur diabetic-oriented convenience flood industry. Also, device meal can be used as ready-prepared food for weight control.

• Journal of Chest Surgery
• /
• v.31 no.5
• /
• pp.466-471
• /
• 1998

Purpose: The safety and efficacy of minimally invasive techniques in congenital heart surgery were tested in this study. Materal and method: Between July 1997 and November 1997, a total of 46 children were underwent minimally invasive cardiac operations at Seoul National University Children's Hospital. Age and body weight of the patients averaged 34.6${\pm}$41.8 (Range: 1∼148) months and 14.5${\pm}$9.9(Range: 3.0∼40.0) kg, respectively. Twenty eight patients were male. Preoperative surgical indications included 15 atrial septal defects, 25 ventricular septal defects, 1 foreign body in aorta, 3 partial atrioventricular septal defects, 1 total anomalous pulmonary venous connection(cardiac type), and 1 tetralogy of Fallot. After creating a small lower midline skin incision starting as down as possible from the sternal notch, a vertical midline sternotomy extended from xyphoid process to the level of the second intercostal space, where one of the T-, J-, I- or inverted C-shaped lower lying mini-sternotomy was completed with a creation of unilateral right or bilateral trap door sternal opening. A conventional direct aortic and bicaval cannulation was routine. Result: A mean length of skin incision was 6.1${\pm}$1.0(range: 4.0∼9.0) cm. A mean distance between the suprasternal notch and the upper most point of the skin incision was 4.0${\pm}$1.1 (range: 2.0∼7.0) cm. Mean cardiopulmonary bypass time, aortic cross-clamp time, and the operation time were 62.9${\pm}$20.0(range: 28∼147), 29.8${\pm}$12.8(range: 11∼79), and 161.1${\pm}$34.5 (range: 100-250) minutes. A mean total amount of postoperative blood transfusion was 71.0${\pm}$68.1 (range: 0∼267) cc. All patients were extubated mean 11.3${\pm}$13.8(range: 1∼73) hours after operation. A mean total amount of analgesics used was 0.8${\pm}$1.8(range: 0∼9) mg of morphine. The mean duration of stay in intensive care unit and hospital stay were 35.0${\pm}$32.2 (range: 10∼194) hours and 6.2${\pm}$2.0(range: 3∼11) days. There were no wound complications and hospital deaths. Conclusion: This short-term experience disclosed that the minimally invasive technique can be feasibly applied in a selected group of congenital heart disease as well as is cosmetically more attractive approach.

• Journal of Chest Surgery
• /
• v.32 no.12
• /
• pp.1093-1099
• /
• 1999

배경 : 류마티스성 승모판막 폐쇄부전증과 퇴행성 승모판막 폐쇄부전증에서 승모판막 성형술의 결과와 비교하여 류마티스성 승모판막 폐쇄부전증에서도 승모팍막성형술이 적합한 치료방법이 될 수 있는지를 알아보았다. 대상 및 방법 : 95년 1월부터 98년 12월 까지 승모판막 성형술을 시행받은 184명의 환자중에서 류마티스성 승모판막 폐쇄부전증 49례(1군)의 퇴행성 승모판막 폐쇄부전증 78례(2군)를 대상으로 하였다. 평균연령은 1군이 36.3$\pm$14.6(16-74세) 2군은 52.5$\pm$13.4(14-77)세였다 총 추적 관찰기간은 1군이 72.2인년 2군이77.2인년이었다 두군에서 수술후와 수술후 6개월 1년 및 이후 1년 단위로 주기적인 심초음파를 시행하였고 이를 통계적 검정하였다. 결과 : 두 군간에 수술전 혈류역학적인 차이를 보이지 않았고 수술전 평균 승모판막 폐쇄 부전의 정도는 1군이 3.0$\pm$0.4, 2군이 3.9$\pm$0.3였으나 수술후 추적 관찰에서 각각 0.9$\pm$0.9와 0.8$\pm$0.7정도의 양호한 판막 성형술의 결과를 보였고 승모판막 면적의 변화나 승모판막에서의 평균압력차이 등 혈류역학적인 결과에도 차이를 보이고 있지 않았다 수술조기 사망과 후기 사망은 없었으며 재수술율은 1군이 인년대비 1.4% 2군이 인년대비 2.6%였고 색전발생율은 1군이 인년대비 2.8% 2군이 1.3%였다. 심내막염발생은 1군에서만 1례있었으며 상기 결과들에서 두군간에 의미있는 차이를 보이고 있지는 않았다 결론 : 향후 장기적인 추적 관찰이 필요하나 중기 성적에서 승모판막 성형술이 류마티스성 승모판막 폐쇄 부전증에서도 효과적인 치료방법임을 알수 있었다.다 출생후 폐포막의 FN의 활성은 출생후 5일 및 7일에 최고주에 달했다. 출생직후 1-2일경에 혈관의 조직내 FN의 활성이 양성을 나타내지만 3일이후 활성이감소되었다. 폐포대식세포내 FN의 활성은 출생후 증가되었다. 폐조직내 소기관지의 FN의 활성은 출생후 완만하게 상승되었다. 큰 폐포세포는 출생 1-3일에 일정량의 FN 반응이 세포질과 미세융모내에 관찰되었다. 결론 : 이상과 같은 결과로 흰쥐의 폐포의 분화과정이 계속되는 출생후 폐에서 FN의 분비는 7일이내에 성숙흰쥐의 폐포내 반응과 비슷한 반응으르 보이며 이때 폐의 실질조직은 분화가 거의 완료되었을 것으로 사료되었고 큰 폐포세포에서도 FN이 분비되는 것으로 결론지울수 있다.X>에서 $1,332.75{\mu}g/mL$으로 최 대값을 나타내었으며, 추출시간 4.24시간 및 시료에 대한 용매비 9.71 mL/g에서 가장 높게 나타났다. 추출온도가 높고, 추출시간이 증가할수록 총 polyphenol 함량이 증가하는 경향을 나타내었다. Gallic acid 함량은 $65.84^{\circ}C$에서 $30.51{\mu}g/mL$으로 최대값을 나타내 었으며, 추출시간 1.65시간 및 시료에 대한 용매비 17.17mL/g에서 가장 높은 추출율을 보였다. Gallic acid 함량에 대한 추출조건의 영향은 추출시간과 용매비에 영향을 받는 것으로 나타났으며, 설정된 범위 내에서 온도에 대한 영향은 거의 나타나지 않는 것으로 나타났다. 실험연구가 더 필요하리라 본다. 혈액학적 변화를 유도하고 환자의 연령, 혈소판 수, 대동맥 차단 시간, 체외 순환 시간, 술후 PT 및 aPTT와 같은 다인적 상황들이 술후 출혈에 영향을 미친다는 점들을 시사하고

• Applied Chemistry for Engineering
• /
• v.23 no.2
• /
• pp.183-189
• /
• 2012

In this study, the cellular protective effect and antioxidative property of peanut sprout root extracts were investigated. Cellular protective effects of peanut sprout root extracts on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethyl acetate fraction of extracts exhibited a cellular protective effect in a concentration dependent manner. Particularly, the aglycone fraction of extracts showed prominent cellular protective effects in a concentration range (5~50 ${\mu}g/mL$). They are more effective than that of (+)-${\alpha}$-tocopherol, known as a lipid peroxidation chain blocker. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of peanut sprout root extracts on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction of extracts ($OSC_{50}$; 1.59 ${\mu}g/mL$) showed a similar ROS scavenging activity compare with that of L-ascorbic acid (1.50 ${\mu}g/mL$), known as a strong antioxidant. On the other hand, the order of free radical (1,1-diphenyl-2-picrylhydraxyl, DPPH) scavenging activity ($FSC_{50}$) was (+)-${\alpha}$-tocopherol > 80% MeOH extract > aglycone fraction > ethyl acetate fraction. These results indicate that peanut sprout root extracts can function as an antioxidant in biological systems, particularly skin exposed to solar UV radiation by scavenging $^1O_2$ and other ROS, and to protect cellular membranes against ROS.

• Korean Journal of Environment and Ecology
• /
• v.37 no.6
• /
• pp.439-449
• /
• 2023

This study was conducted to verify the role of forest roads in the extinction of large forest fires in Korea. The study area was the forest fire-damaged area of Gangneung City, Gangwon Special Self-Governing Province, in April 2023, which is one of the areas with the highest road density among the major forest fires that have occurred so far. The scope of the forest fire damage area was confirmed through on-site survey, and the intensity of the fire was carried out through Sentinel-2 satellite imagery analysis. After that, the relationship between the damage range and intensity and the forest road was examined. About 59.6 km of roads were built within 50 m from the boundary of the forest fire damage area, which can easily access the entire 149.1 ha of forest fire damaged area. The road density is as high as 168.9 m/ha. All forests that were fragmented by roads were fragmented into 83 places, and all of these forests could be judged to have spread by spotting fire. As a result of analyzing the distribution of damage intensity by distance from the road to see the extent of damage according to the ease of access of fire extinguishing vehicles, it was confirmed that the proportion of areas with low-intensity damage has increased sharply even from 75 m or more away from the road. The results of analyzing the distribution of damage intensity by altitude to see the extent of damage according to the ease of access of fire extinguishing showed that the proportion of areas with low-intensity damage increased as the altitude increased, while the proportion of areas with damage of more than strong intensity decreased as the altitude increased. It was confirmed that there is no data that roads inside or adjacent to forests in the forest fire area of Gangneung City are effective in extinguishing forest fires. These results are contrary to the logic that increasing the road density in forests is effective in extinguishing forest fires. In the case of this fire area in Gangneung City, the road density is 43 times higher than the current road density in Korea claimed by the Korea Forest Service of 3.9 m/ha. This study suggests that roads can be a hindrance to extinguishing forest fires.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.40 no.5
• /
• pp.100-108
• /
• 2012

The purpose of the study was to evaluate the influence of shading and ventilation on Mean Radiant Temperature(MRT) of the outdoor space at a summer outdoor. The Wind Speed(WS), Air Temperature(AT) and Globe Temperature(GT) were recorded every minute from $1^{st}$ of May to the $30^{th}$ of September 2011 at a height of 1.2m above in four experimental plots with different shading and ventilating conditions, with a measuring system consisting of a vane type anemometer(Barini Design's BDTH), Resistance Temperature Detector(RTD, Pt-100), standard black globe(${\O}$ 150mm) and data acquisition systems(National Instrument's Labview and Compfile Techs' Moacon). To implement four different ventilating and shading conditions, three hexahedral steel frames, and one natural plot were established in the open grass field. Two of the steel frames had a dimension of $3m(W){\times}3m(L){\times}1.5m(H)$ and every vertical side covered with transparent polyethylene film to prevent lateral ventilation(Ventilation Blocking Plot: VP), and an additional shading curtain was applied on the top side of a frame(Shading and Ventilation Blocking Plot: SVP). The third was $1.5m(W){\times}1.5m(L){\times}1.5m(H)$, only the top side of which was covered by the shading curtain without the lateral film(Shading Plot: SP). The last plot was natural condition without any kind of shading and wind blocking material(Natural Open Plot: NP). Based on the 13,262 records of 44 sunny days, the time serial difference of AT and GT for 24 hour were analyzed and compared, and statistical analysis was done based on the 7,172 records of daytime period from 7 A.M. to 8 P.M., while the relation between the MRT and solar radiation and wind speed was analyzed based on the records of the hottest period from 11 A.M. to 4 P.M.. The major findings were as follows: 1. The peak AT was $40.8^{\circ}C$ at VP and $35.6^{\circ}C$ at SP showing the difference about $5^{\circ}C$, but the difference of average AT was very small within${\pm}1^{\circ}C$. 2. The difference of the peak GT was $12^{\circ}C$ showing $52.5^{\circ}C$ at VP and $40.6^{\circ}C$ at SP, while the gap of average GT between the two plots was $6^{\circ}C$. Comparing all four plots including NP and SVP, it can be said that the shading decrease $6^{\circ}C$ GT while the wind blocking increase $3^{\circ}C$ GT. 3. According to the calculated MRT, the shading has a cooling effect in reducing a maximum of $13^{\circ}C$ and average $9^{\circ}C$ MRT, while the wind blocking has heating effect of increasing average $3^{\circ}C$ MRT. In other words, the MRT of the shaded area with natural ventilation could be cooler than the wind blocking the sunny site to about $16^{\circ}C$ MRT maximum. 4. The regression and correlation tests showed that the shading is more important than the ventilation in reducing the MRT, while both of them do an important role in improving the outdoor thermal comfort. In summary, the results of this study showed that the shade is the first and the ventilation is the second important factor in terms of improving outdoor thermal comfort in summer daylight hours. Therefore, it can be apparently said that the more shade by the forest, shading trees etc., the more effective in conditioning the microclimate of an outdoor space reducing the useless or even harmful heat energy for human activities. Furthermore, the delicately designed wind corridor or outdoor ventilation system can improve even the thermal environment of urban area.