• Journal of Wetlands Research
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• v.17 no.1
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• pp.1-10
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• 2015

The bleaching phenomenon of otter spraints is indicates that the age of spraints (fresh or old spraints). As previous studies on the old otter faeces (spraint) have focused only on the external changes of spraints, it has been difficult to explain the difference of the decomposition rates among old spraints. We hypothesized that the micrometeorology difference caused by various characteristics of sprainting sites such as porosity and consistency of soil could affect the extent of the decomposition rate, the solar bleaching phenomenon of spraints used as a measure of the patterns of old spraints. Sprainting sites were classified into four types (Clay, Sand, Rock and Concrete spot) and each type was divided into two groups according to the sunlight condition (Sunny site and Shady site) to measure the effect of solar radiation. Micrometeorology of the sites were evaluated by measuring temperatures and humidities of the sites during the whole season. The variations in micrometeorology of the sunny sites according to the sprainting site types were examined with correlation analyses between the factors of micrometeorology. The analyses on the bleaching phenomenon of the spraints by micrometeorology showed that the highest rate of bleaching was found at the 'Rock spot' and 'Concrete spot' of the sunny site and especially in summer, the highest rate of bleaching ($63.4{\pm}7.6%$) was found at the 'Clay spot' of the sunny sites. The lowest rate of bleaching was found at the 'Sand spot' of the sunny sites. The above findings show that the difference in bleaching rates among sprainting sites was due to the seasonal or sunny condition. In addition, we found that the differences in thermal conductivity among sprainting site characteristics have resulted in different sprainting site temperature which have affected the rate of bleaching of spraints. In conclusion, this study suggests that studies of otters on their population size and home ranges using spraints as an indirect sign, should consider the effects of sprainting site characteristics and weather conditions.

• Korean Journal of Plant Resources
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• v.34 no.4
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• pp.287-296
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• 2021

Recently, the pace of global climate change has tremendously increased, causing extreme damage to crop production. Here, we aimed to examine the growth characteristics and useful components of Angelica gigas under extreme heat stress, providing fundamental data for its efficient cultivation. Plants were exposed to various experimental temperatures (28℃, 34℃, and 40℃), and their growth characteristics and content of useful components were analyzed. At the experimental site, the ambient and soil temperature were 19.38℃ and 21.34℃, ambient and soil humidity were 81.3 % and 0.18 m³/m³, solar radiation was 162.05 W/m². Moreover, the soil was sandy-clay-loam (pH 6.65), with 2.66% organic matter, 868.52 mg/kg soil available phosphate, and 0.14% nitrogen. Values of most growth characteristics, including the survival rate (85%), plant height (38.66cm), and fresh and dry weight (41.3 g and 14.24 g), were the highest at 28℃. Although the highest content of useful components was observed at 34℃ (3.24%), there were no significant differences across temperatures. Growth characteristics varied across temperatures due to detrimental effects of heat stress, such as accelerated tissue aging, reduced photosynthesis, and delay of growth. Similar content of useful components across temperatures may be due to poor accumulation of anabolic products caused by impaired growth at extremely high temperatures.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.118-124
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• 1998

Minimally invasive coronary artery bypass grafting without using cardiopulmonary bypass (CPB) is a recently accepted modality of myocardial revascularization prcedures which is particularly suitable to the patients with lesions in the left anterior descending(LAD) and the right coronary arteries. Of the consecutive 35 patients of coronary artery bypass grafting performed at Sejong General Hospital from March to August 1996, six patients underwent minimally invasive coronary artery bypass grafting without CPB. All had stenotic lesions of the LAD more than 90%. Bypass grafting of the LAD was approached through midline sternotomy in one, through ministernotomy in two, and through limited left anterior thoracotomy in three patients, respectively. The internal mammary arteries were prepared without the use of thoracoscope. The mobilized mammary arteries were connected directly to the LAD in 5 patients, and the anastomosis required interposition of a segment of the radial artery in the remaining one. The diagonal branch was revascularized with the saphenous vein graft at the same time in one patient. No blood transfusion was necessary in 2 patients, and average blood required during surgery was 800ml in 4 patients. All patients were extubated from 4 to 14 hours(mean 9 hours) after operation. Early postoperative coronary angiography in 5 patients between 7 and 10 days after surgery has proved full patency of the grafts. With these limited clinical experiences, the clinical results demonstrated that minimally invasive coronary artery bypass grafting without CPB is an useful procedure especially in patients with isolated lesion in the proximal LAD.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.4
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• pp.259-264
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• 2001

Typhoon and neap tide on Cochlodinium polykrikoides bloom and water temperature on disappearance of C. polykrikoides bloom were investigated to elucidate the outbreak mechanism of C. polykrikoides blooms at Naro and Namhae coastal area in South Sea of Korea. The first observation of C. polykrikoides blooms were observed when thermocline was disappeared by typhoon, tide, etc. The first blooms of C. polykrikoides were observed on neap tide or before one day from neap tide in 1996-1998 and 2000. However, thermocline was disappeared by typhoon in 1994 and 1999, the first blooms were observed early 12-30 day than 1996-1998 and 2000. The main reason of disappearance of C. polykrikoides blooms after typhoon on 1997-2000 seems to be other environmental change by typhoon rather than low water temperature. In the future, the first C. polykrikoides bloom will be appear around the first neap tide of latter part of August with breaking down of thermocline, but if the thermocline be collapsed by typhoon in July, the C. polykrikoides bloom will be appear at beginning of August. The outbreak of C. polykrikoides blooms will be explain as follows: The vegetative cells, which was germinated by environmental change or already exist in surface water at low level, input to the surface water, and then nutrients and trace metals which were suppled from out side of C. polykrikoides bloom area inflow to surface. The vegetative cells are growth by the nutrients and trace metals at suitable environmental conditions e.g. water temperature, salinity, and sufficient light.

• Journal of Bio-Environment Control
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• v.29 no.1
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• pp.20-27
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• 2020

The study was performed to calculate canopy temperatures and crop water stress index (CWSI) of 2-year-old 'Yumi' peach trees using thermal infrared imaging under different soil water conditions, and to evaluate availability for water stress determination. Canopy temperatures showed similar daily variations to air temperatures and they were higher during the daytime than air temperatures. Canopy temperatures for 24 h were correlated highly to air temperatures (r² =0.95), solar radiations (r² =0.74), and relative humidity (r² =-0.88). In addition, soil water potential showed a highly negative correlation to canopy temperatures (r² =-0.57), temperature differences between leaf and air (TD) (r² =-0.71), and CWSI (r² =-0.72) during the daytime (11 to 16 h). CWSI for 24 h was highly related to canopy temperatures (r² =0.90) and TD (r² =0.92), whereas CWSI was not correlated to soil water potential (r² =-0.27) for 24 h but related highly to water potential (r² =-0.72) during the daytime (11 to 16 h). Correlation coefficients between CWSI (y) and soil water potential (x) were highest from 11 to 12 h and a regression equation was deduced as y = -0.0087x + 0.14. CWSI was calculated as 0.575 at -50 kPa, which soil water stress generally occurs. Thus our result suggests that this regression equation using thermal infrared imaging is useful to evaluate soil water stress of peach trees.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.24-32
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• 1985

The worm development and egg laying pattern of Echinostoma hortense (Trematoda; Echinosto-matidae) were studied in albino rats and the brief clinical course was observed in human volunteers. A total of 21 rats were infected with 20~69 metacercariae each and two humans were with 7 and 27 metacercariae, which were collected from the loaches. For recovery of worms, the rats were sacrificed at irregular intervals from the 6th to 150th day after infection and the human volunteers were treated with praziquantel and purged with magnesium salt on the 26~27th day. The stools of the rats and humans were examined for the eggs. The results were as follows: 1. The worm recovery rate from the rats was not affected by the increase of infection time but varied individually; 9.1~50.0% (31.1 % in average). From humans, 14.3% and 37.0% (32.4% in average) of challenged were recovered. 2. In the rats, it was revealed that the worms rapidly grew for the first 14 days to become 7.59mm in average length and 1.17mm in average width but the growth became much slower thereafter until the 150th day; 7.95mm in length on the 21 th day, 9.04mm on the 28th day, 10.21mm on the 49th day and 12. 62mm on the 150th day. During the early stage of infection, the growth of genital organs (male or female) was expressed as sigmoid curves whereas non-genital organs (such as suckers) was simply as straight lines. 3. The prepatent period of this fluke was 10~12 days in the rats and 16~17 days in men. After the start of oviposition, the egg production by the worms remarkably increased, reached maximum on the 32~33th day, followed by decrease thereafter. The maximum value of E.P.G./worm was 390. 4. The major subjective symptoms in human volunteers were abdominal pain and diarrhea during the early stage of infection. The results show that human is as susceptible as the rats to E. hortense infection and the amount of egg production in the rats is greatly affected by the age of worms.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.28-35
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• 1985

This work Was carried out to obtain the most suitable crop coefficient for the paddy rice growing in Taegu area. The result was due to the comparative measurements of evapotranspiration formula in terms of Blaney & Criddle and eight other formulas with those produced by experiment particularly in this area. The crop coefficient, evapotranspiration and transpiration ratio produced by this research are hopefully expected to be of service in the future calculation of evapotranspiration without repeating experiment respectively, whenever the water requirement of paddy rice is planned in Taegu and its vicinity. The accomplished results could be summarized as follows : The maximum amount of evapotranspiration was recorded in the early and middle parts of August. The average reading of evapotranspiration was 6.33mm/day throughout the growth. The evapotranspiration had a highly significant correlation with pan evaporation, solar radiation, sunshine hours and relative humidity of meteorological elements. K and Kc by the use of Blaney & Criddle formula calculated at 0.76 to 1.45 and 0.82 to 1.27, respectively. Its peak value appeared commonly in early August. The ratio of transpiration was 269.03.

• Journal of Bio-Environment Control
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• v.14 no.3
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• pp.149-154
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• 2005

It is very important to make shorter and healthier pot plants with increased numbers of branch at a growing stage before short-day exposure. Especially light and nutrient conditions directly affect the growth and quality of the plants as described above. In this study, the effects of nutrient strength and light intensity on the nutrient uptake and growth of young Kalanchoe plants (Kalanchoe blossfeldiana 'Marlene') during this growth stage were investigated. The plants were grown under two radiation integral (15.8 and 7.9 $mol{\cdot}m^{-2}{\cdot}d^{-1}$, PPF) and three EC (0.8, 1.6 and 2.4 $dS{\cdot}m^{-1}$) conditions. Leaf area, fresh weight, dry weight and number of branch were higher at a higher PPF, and this tendency was more evident at an EC above 1.6$dS{\cdot}m^{-1}$. The plants became higher at a lower PPF. When the EC was at 0.8 $dS{\cdot}m^{-1}$, the plants did not grow so healthy regardless of PPF conditions. EC decrement in the nutrient solution was increased with increase of nutrient strength. With growth stage, the nutrient uptake was increased with increases of nutrient strength and PPF. At a higher PPF, $NO_3-N,\;K^{+}\;and\;Ca^{2+}$ were much more absorbed, and especially the uptake of $K^{+}$ was 1.1 to 1.5 times greater than that or $NO_3-N$. From the results, the EC needed above 1.6 $dS{\cdot}m^{-1}$ during the seedling stage in order to make more healthy Kalanchoe plants having more leaf area, fresh weight, dry weight and number of branches under adequate light conditions.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.400-406
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• 2018

In this experiment the effect of supplemental lighting on the growth and yield of cucumber (Cucumis sativus L. 'Fresh') plants during low radiation period of winter season were investigated in glasshouses using common high-pressure sodium (HPS) lamps and newly developed plasma lighting system (PLS) lamps. Plants grown without supplemental lighting were considered as a control. Supplemental lighting was provided from November 20th, 2015 to March 15th, 2016 to ensure 14-hour photoperiod (natural+supplemental light), also lamps were operated automatically when the outside sun radiation levels were less than $100W{\cdot}m^{-2}$. Spectral analysis showed that HPS lamp had a discrete spectrum, lacked of the radiation in the 400-550 nm wave band (blue-green light), but had a high output in the orange-red region (550-650 nm). A higher red light output resulted in an increased red to far-red (R/FR) ratio in HPS lamp. PLS had a continuous spectrum and had a peak radiation in green region (490-550 nm). HPS has 12.6% lower output in photosynthetically active radiation (PAR) but 12.6% higher output in near infra-red (NIR) spectral regions compared to PLS. Both HPS and PLS lamps emitted very low levels of ultra-violet radiation (300-400 nm). Supplemental lighting both from HPS and PLS lamps increased plant height, leaf number, internode number and dry weight of cucumber plants compared to control. Photosynthetic activity of cucumber plants grown under two supplemental lighting systems was comparable. Number of fruits per cucumber plant (fruit weight per plant) in control, PLS, and HPS plots were 21.2 (2.9 kg), 38.7 (5.5 kg), and 40.4 (5.6 kg), respectively, thereby increasing yield by 1.8-1.9 times in comparison with control. An analysis of the economic feasibility of supplemental lighting in cucumber cultivation showed that considering lamp installation and electricity costs the income from supplemental lighting increased by 37% and 62% for PLS and HPS lamps, respectively.

• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.751-762
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• 2010

In order to understand the influence that the plant cover condition of the high-rise building outer space causes to the temperature change, we selected 12 high-rise building constructed in Seoul City. The land cover type of the outside was classified into six type(outer road, paved surface, shrub/grassland, single-layer tree planting-site, multi-layer planting-site, and waterscape facilities) and the temperature was measured at the representative point for each type in order to analyze the land cover temperature differential for each type of the high-rise building outer space. The study area showing the temperature tendency to be similar based upon one way analysis of variance after selecting the central part of the outer road for a control and measuring a temperature in order to consider the neighboring environmental difference of the dozen building was classified into 4 groups. As to the one-way layout result of variance analysis with the land cover type of the classified group and outer space temperature, the single-layer tree planting-site, waterscape facilities, and multi-layer planting-site belonged mainly to the low temperature section. The shrub/grassland, paved surface, and outer road belonged to the high temperature region. The temperature difference between low temperature region and high temperature region is about $1.06{\sim}6.17^{\circ}C$. However, the temperature in the Outer Space of the Super-High-Rise Building was variously appeared by the influence such as the cramped of the created planting-site and waterscape facilities area, the increase of amount of solar radiation and the reduction of reflection amount of light due to building etc.. Thus, the composition all produced the area of the green quantity required for each space and water space in advance. It was determined that there were the minimum area displaying an effect and the necessity to it secures the green quantity.