• Korean Chemical Engineering Research
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• v.47 no.2
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• pp.220-229
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• 2009

Strain improvement and morphology investigation in bioreactor cultures were undertaken in suspended cultures of Phellinus linteus mycelia for mass production of protein-bound polysaccharides(soluble ${\beta}$-D-glucan), a powerful immuno-stimulating agent. Phellineus sp. screened for this research was identified as Phellinus linteues through ITS rDNA sequencing method and blast search, demonstrating 99.7% similarity to other Phellinus linteus strains. Intensive strain improvement program was carried out by obtaining large amounts of protoplasts for the isolation of single cell colonies. Rapid and large screening of high-yielding producers was possible because large numbers of protoplasts ($1{\times}10^5{\sim}10^6\;protoplasts/ml$) formed using the banding filtration method with the cell wall-disrupting enzymes could be regenerated in relatively high regeneration frequency($10^{-2}{\sim}10^{-3}$) in the newly developed regeneration medium. It was demonstrated that the strains showing high performances in the protoplast regeneration and solid growth medium were able to produce 5.8~6.4%(w/w) of ${\beta}$-D-glucan and 13~15 g/L of biomass in stable manners in suspended shake-flask cultures of P. linteus mycelia. In addition, cell mass increase was observed to be the most important in order to enhance ${\beta}$-D-glucan productivity during the course of strain improvement program, since the amount of ${\beta}$-D-glucan extracted from the cell wall of P. linteus mycelia was almost constant on the unit biomass basis. Therefore we fully investigated the fungal cell morphology, generally known as one of the key factors affecting cell growth extent in the bioreactor cultures of mycelial fungal cells. It was found that, in order to obtain as high cell mass as possible in the final production bioreactor cultures, the producing cells should be proliferated in condensed filamentous forms in the growth cultures, and optimum amounts of these filamentous cells should be transferred as active inoculums to the production bioreactor. In this case, ideal morphologies consisting of compacted pellets less than 0.5mm in diameter were successfully induced in the production cultures, resulting in shorter period of lag phase, 1.5 fold higher specific cell growth rate and 3.3 fold increase in the final biomass production as compared to the parallel bioreactor cultures of different morphological forms. It was concluded that not only the high-yielding but also the good morphological characteristics led to the significantly higher biomass production and ${\beta}$-D-glucan productivity in the final production cultures.

• Journal of Environmental Policy
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• v.6 no.1
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• pp.1-40
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• 2007

The research in this paper, for the effective implementation of CBD PoW PA(Program of Work on Protected Areas of Convention on Biological Diversity) that was adopted by CBD COP7(Conference of the Parties) in 2004, shows the objectives and activities of 9 each subject in PoW PA regarding domestic status and cases of national park management. Before anything else, according to the result of the review on the status of protected areas in Korea, there are 1,119 protected areas which are classified into 14 types and the total area is about $15,621km^2$. After a thorough review on 9 each subject about the implementation of CBD PoW PA, we found out that some parts such as management planning, prevention and alleviation of threats, and establishment of PAs system, are improved while financial support, improved social benefit, and MEE(Management Effectiveness Evaluation} fields are need to be improved. Especially regarding time-bound, ecological gap analysis on national level and MEE are need to be improved immediately. This paper could help us to understand the current status of PAs management system in Korea and to prepare national reports of CBD and implementation report of PoW PA. Based on research and results of this paper, we need to find the fields that have gaps in order to meet the requirements of the CBD PoW PA and the implementation tools that are suitable for managing Korea's protected areas. To effectively implement the various activities which require a systematic approach on the national level, the establishment of the networks among relevant organizations for protected areas are vital. To effectively reach the ultimate goal of CBD PoW PA, reducing the rate of biodiversity loss, it is essential that lots of plans established by authorities must be carried out in a constant manner to achieve goals of CBD PoW PA.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.662-673
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• 1999

Background : Pressure-controlled ventilation (PCV) is frequently used recently as the initial mode of mechanical ventilation in the patients with respiratory failure. Theoretically, because of its high initial inspiratory flow, pressure-controlled ventilation has lower peak inspiratory pressure and improved gas exchange than volume-controlled ventilation (VCV). But the data from previous studies showed controversial results about the gas exchange. Moreover, the comparison study between PCV and VCV with various inspiration : expiration time ratios (I : E ratios) is rare. So this study was performed to compare the respiratory mechanics and gas exchange between PCV and VCV with various I : E raitos. Methods : Nine patients receiving mechanical ventilation for respiratory failure were enrolled. They were ventilated by both PCV and VCV with various I : E ratios (1 : 2, 1 : 1.3 and 1.7 : 1). $FiO_2$, tidal volume, respiratory rate and external positive end-expiratory pressure (PEEP) were kept constant throughout the study. After 20 minutes of each ventilation mode, arterial blood gas, airway pressures, expired $CO_2$ were measured. Results : In both PCV and VCV, as the I : E ratio increased, the mean airway pressure was increased, and $PaCO_2$ and physiologic dead space fraction were decreased. But P(A-a)$O_2$ was not changed. In all three different I : E ratios, peak inspiratory pressure was lower during PCV, and mean airway pressure was higher during PCV. But $PaCO_2$ level, physiologic dead space fraction and P(A-a)$O_2$ were not different between PCV and VCV with three different I : E ratios. Conclusion : There was no difference in gas exchange between PCV and VCV under the same tidal volume, frequency and I : E ratio.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.654-661
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• 1999

Background : The upper respiratory tract is the primary target organ of various airborne pollutants and is easily accessible part of the respiratory tract, and also is the predominant structure where chronic cough originates. The nasal peak inspiratory flow(PIFn), which is the peak inspiratory flow via nose with nasal mask and spirometry, could be a reliable parameter of nasal obstruction. The validity of PIFn has been evaluated in several studies by assessing the correlation between PIFn measurements and other parameters of nasal air flow. This study was designed to show the reproducibility of PIFn, the difference of PIFn between patients with chronic cough and normal subjects, and the usefulness of PIFn in the evaluation of nasal obstruction in patients with chronic cough. Methods : PIFn was measured by spirometry with nasal mask, twice a day for 3 consecutive days in 7 young normal subjects to evaluate validity of the test. In 32 patients with chronic cough and 25 age-matched normal subjects, PIFn and pulmonary function test($FEV_1$, $FEV_1%$ pred, FVC, and FVC% pred) were measured at first visiting. Results : Values of PIFn, $FEV_1$, and FVC were nearly constant in 7 young normal adults. Patients with chronic cough were 32 (14 males and 18 females) and the mean age was $41.4{\pm}15.9$ years. Normal subjects were 32(22 males and 10 females) and the mean age was $39.8{\pm}18.6$ years. There was no significant difference of age and pulmonary function test between patients with chronic cough and normal subjects(p<0.05). The PIFn values in patients with chronic cough was significantly lower than those of normal subjects($2.25{\pm}0.68\;L/sec$ vs. $2.75{\pm}1.00\;L/sec$ ; p=0.02). The postnasal drip syndrome(PNDS) comprised the majority of patients with chronic cough(27). The PIFn in patients with PNDS was significantly lower than that of normal subjects (mean$\pm$SD ; $2.18{\pm}0.66$ vs. $2.75{\pm}1.00\;L/sec$, p=0.006). Conclusion : There was a significant difference of PIFn between patients with chronic cough and normal subjects. Among the patients with chronic cough, patients with PNDS showed the most significant difference with normal subjects in PIFn. The PIFn could be a useful parameter of nasal obstruction in patients with chronic cough, especially in patients with PNDS.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.2
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• pp.79-85
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• 1981

As one of the fundamental studies for the breeding of marine algae, the effects of several plant hormones (IAA, Gibberellin, 2.4-D, NAA, Kinetin) on the growth of Porphyra-fronds, P. tenera Kjell. form tamatsuensis Miura, were investigated from January 21 to February 21 1981. The fronds used for the experiment were dissected out at $25mm^2$ size, and cultured in modified Provasoli's ESP medium supplemented with various concentrations of each plant growth regulators. The culture was kept under constant water temperature of $5^{\circ}C$ in 14 hrs. photoperiod and illuminated with 2,400 lux by fluorescent light. Based on the results of first experiment, the culture of fronds for the secondary experiment was carried out at $5^{\circ}C\;and\;10^{\circ}C$ in medium containing various levels of Kinetin from April 6 to 24, and compared the growth of two groups at each concentrations with each other, The results obtained are summarized as follows : (1) The best growth efficiencies were observed at 5.0mg/1 of each plant hormones except Gibberellin. Among them, the highest growth-rate was $312.5\%\;(345.3\%\;in\;frond\;size)$ in contrast with control at 5.0mg/1 of Kinetin, and was followed by $257.5\%\;(236.1\%)$ in 2.4-D,$166.7\%(147.6\%)$ in IAA and $141.7\%\;(167.7\%)$ in NAA, but that in Gibberellin was $247.9\%(241.9\%)$ at 10.0mg/l. (2) Especially, the fronds cultured at 5.0mg/1 of Kinetin were deep black-brown in colour, and had vivid, healthy chloroplasts in their all cells. On the contrary, the fronds cultured in other media were discoloured to light black-brown or green-drown, and almost all cells were vacuolated or shrunk gradually into death.(3) There was an obvious difference between the best growth-rates of the fronds cultured at 5.0mg/l of Kinetin at $5^{\circ}C$ and those at $10^{\circ}C$. The former was $366.7\%$, the latter $318.8\%$ but the difference was little at lower concentrations. (4) Many abnormal cells grown up to $25.0-27.5\mu$ in diameter were found among the marginal cells of fronds which showed the best growth in Kinetin, and the fronds wire $41.0-42.0\mu$ in thickness which was thicker by $10.0\mu$ or so than the others. (5) In two fronds at 1.0mg/1 of Kinetin cell-divisions were observed, which might developed into antheridium, but it was doubtful whether due to the efficiency of Kinetin.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.353-360
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• 2017

In this study, the design and performance test of the air to water heat pump capable of producing hot water for greenhouse heating by using the surplus solar heat inside the greenhouse and the air heat outside greenhouse as the selective heat source were conducted. The heat storage operations using the surplus solar heat and the outside air heat were designed to be switched according to the setting temperature of the greenhouse in consideration of the optimum temperature range of the crop. In the developed system, it was possible to automatically control the switching of heat storage operation, heating and ventilation by setting 12 reference temperatures on the control panel. In the selective heat storage operation with the surplus solar heat and outside air heat, the temperature of thermal storage tank was controlled variably from $35^{\circ}C$ to $52^{\circ}C$ according to the heat storage rate and heating load. The heat storage operation times using the surplus solar heat and outside air heat were 23.1% and 30.7% of the experimental time respectively and the heat pump pause time was 46.2%. COP(coefficient of performance) of the heat pump of the heat storage operation using the surplus solar heat and outside air heat were 3.83 and 2.77 respectively and was 3.24 for whole selective heat storage operation. For the comparative experiment, the heat storage operation using the outside air heat only was performed under the condition that the temperature of the thermal storage tank was controlled constantly from 50 to $52^{\circ}C$, and COP was analyzed to be 2.33. As a result, it was confirmed that the COP of the heat storage operation using the surplus solar heat and outside air heat as selective heat source and the variable temperature control of the thermal storage tank was 39% higher than that of the general heat storage operation using the outside air heat only and the constant temperature control of the thermal storage tank.

• Parasites, Hosts and Diseases
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• v.28 no.3
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• pp.183-194
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• 1990

In an attempt to develop prophylactic and therapeutic measures of the intestinal giant-cystic disease caused by Thelohanellus kitauei in the Israel carp, Cyprinus carpio nodus, pathological observations were conducted upon the carps which were hatched in May 1988 and raised in a net cage fish farm at the Soyang lake, managed by Horim Fisheries for the period of 21 months with 1~2 months interval. After a gross inspection of the carps, necropsy was carried out periodically in order to clarify the pathological changes in various internal organs and muscular tissues. Also. the prevalence of the disease was checked during the period from 1988 to 1990. Gross inspections revealed that the infected carps showed some degree of fading in body and gill color, back-emaciation symptoms, reddish anus accompanying erosion and relaxation and pot-belly, as well as discharge of yellowish white mucoid material from the anus. However, most carps died eventually of intestinal obstruction. Other significant necropsy fadings included cyst formation of various size in the intestinal mucosa, ascites, anemic condition through internal organs and muscular tissues, hyperemia and dilation of intestines with decreased tension, thinness and fragility, and full contents of semi-fluid or yellowish white mucoid material in the intestinal canals. Based on the morphological characteristics of the spores found in the cysts, parasitic location in the intestines, macro- and microscopic findings of the lesions, the parasites were identised as Thelohanellus kitauei Egusa os Nakajima, 1981. Although monthly changes of water temperature were distinct, the extrusion rates of the polar filaments of the spores stayed constant throughout the year with an exception of a lower rate in July, The lesions initiated from mucosa and submucosa in early July became large swellings and then complete mature (orms following the peracute course. From late August the upper cysts were gradually opened and most of the spores were dispersed from anus into the surrounding water through December but only a few lasted until next April. The cysts were completely recovered until next September. Comparing the incidence and prevalence of the disease by year tremendous infection and death rates were checked in the first prevalent year, 1988, but the rates were significantly decreased in the second year, and showed an almost normal status in the third year, 1990. As the above summarized results showed, the disease entity might come to an end in three years after the first prevalent year, however, the spores must be strictly prevented because they could be infective in the water for one year.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.603-609
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• 1992

To investigate the effect of polyethylene film packaging and $CO_2$ treatment on tomatoes during storage, the gas composition in film, weight loss, the changes of color, hardness and several components were measured. The concentrations of $CO_2$ and $O_2$ in film were changed rapidly in early stage, but it kept a constant level after 7 days of storage. In 0.06 mm polyethylene film, $CO_2$ and $O_2$ concentration was kept a level of $4{\sim}6%$ respectively. The increase in $C_2H_2$ concentration was delayed in thick and $CO_2$ treated film. The rate of weight loss was 4% in non-packed tomatoes, but it recorded about 1% in 0.06 mm polyethylene film. Titratable acidity, pH and soluble solids were changed slightly, but the obvious differents were not observed according to film thickness and $CO_2$ treatment. The value of tomatoes was increased but L and b values were not changed greatly during storage. These color changes were restricted by 0.06 mm film and $CO_2$ treatment. The firmness and content of ascorbic acid were reduced during storage but it restrained by $CO_2$ treatment and film packaging. Sugar of tomatoes were composed of glucose, fructose and a very small amount of sucrose, and they were changed little during storage.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.159-176
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• 1996

This study is aimed at reviewing the methods of joint cost allocation and allocating the joint cost of estuary dam with specially repect to Kumgang Large-scale Agricultural Comprehensive Development Project. Apart from the water resource development project propelled by Water Resource Development Corporation in connection with Law of Multipurpose Dam Development, the Largescale Comprehensive Agricultural Development Projects couldn't ins-titutionally be carried out cost allocation of common facilities, even though it were concerned with irrigation, municipal and industrical water supply, flood control, sightseeing and industrial zone development components. To decrease farmer's burden of the project costs and, operation and maintenance costs, the joint costs of common facilities like estuary dam included in agricultural development projects have to be allocated by suitable method as alternative cost-remaining benefit method and the analytical activity should be supported by revising the concerned laws as Rural Development and Promotion and, Rural Rearrangement conpatible with the law for multipurpose dam development. Kumgang Agricultural Comprehensive Development Project was selected as a case study for the estimation of socio-economic benefits by project components and joint cost allocation of the estuary dam. The main results of the study are as follows; Joint cost allocation and unit charges by components 1. The project area will be 25,554ha with total project cost of 624,860 million won including the estuary dam cost of 120,843 million won. The project costs were ex-pressed by 1994 constant price. 2. Total quantity of water was estimated 365 million tons which were consisted of 245 million tons for irrigation, 73 million tons for municipal water and 47 million tons for industrial water. 3. The rates of joint cost allocation were amounted to 34.2% for agriculture, 2.5% for sightseeing, 45.7% for transportation, 11.8% for M & I water supply and 5.8% for flood control respectively. 4. The unit financial charges by project components were estimated at 7.88 won per ton for irrigation, 16.11won for M & I water, 1,686won per vehicle one pass, 977won per Pyeong according to the capital recovery method. The financial charges using straitline method for depreciation were estimated at 7.88won per ton for irrigation, 9.12won per ton for M & I water, 624won per vehicle one pass for transportation and 331won per Pyeong for sightseeing area. 5. The unit economic charges by project components were estimated at 21.1 won per ton for irrigation, 15.2won for M & I water, 977won per vehicle one pass, 977won per Pyeong according to the capital recovery method. The economic charges using straitline method for depreciation were estimated at 11.72won per ton for irrigation, 8.61won per ton for M & I water, 331won per vehicle one pass for transportation. Policy recommendation 1. The unit operation and maintenance costs for irrigation water in the paddy field couldn't be imposed as the water resource cost untreated. 2. The dam costs including investment cost and O & M cost, as a joint cost, had to be allocated by each benefited components as transportation, M & I water supply, flood control, irrigation and drainage, and sightseeing. But the agricultural comprehensive project have been dealt as an irrigation project without any appraisal socio-economic benefits and any allocating the joint cost of estuary dam. 3. All the associated project benefits and costs must be evaluated based on accounting principle and rent recovery rate of the project costs and O & M costs should be regulated by the laws concerned. 4. The rural development and promotion law and rural rearrangement law have to be revised comprising joint cost allocation considering free rider problems. 5. The government subsidy for the agricultural base development project has to be covered all the project costs. In case of common facilities representing joint cost allocation problems, all the allocated casts for other purposes like transportation and M & I water supply etc. should be recovered for formation in investment fund for agricultural base development and to procure O & M costs for irrigation facilities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.270-278
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• 2009

To understand the seed characteristics among cultivated types of Perilla crop and their weedy types in Korea and Japan, we studied the variation of 69 accessions by examining weight of 100 seeds, hardness of seed, germination percent and germination energy. The survey of the weight of 100 seeds and hardness of seed, clarified as follows; cultivated type of var. frutescens showed a range of 0.177 to 0.402 g with weight of 100 seeds, and most accessions of cultivated type of var. frutescens have soft seeds, except for several accessions, which have hard seeds, whereas weedy type of var. frutescens showed a range of 0.045 to 0.172 g with weight of 100 seeds, and has only hard seeds. While cultivated type of var. crispa showed a range of 0.054 to 0.101 g with weight of 100 seeds, and has only hard seeds. The weedy type of var. crispa showed a range of 0.059 to 0.135 g with weight of 100 seeds, and has only hard seeds. According to the result of germination tests, although the most accessions of cultivated and weedy types of var. frutescens and cultivated and weedy types of var. crispa showed below 50% germination rate at the first germination test, but some accessions of cultivated type of var. frutescens showed above 50% germination. While, in the second or third germination tests, most accessions of cultivated types of Perilla crop and their weedy types showed above 50% germination rates, except for several accessions. As a result, in this study, the average of germination percent and germination energy among accessions of cultivated types of Perilla crop and their weedy types showed respectively the highest value at the third germination test, but showed the lowest value at the first germination test. In addition, the germination percent and germination energy showed much higher in the room temperature condition than in $28^{\circ}C$ constant-temperature condition. Although our results may be required much clearly survey in the further study, this current results will be help for our understanding the variation of seed characteristics among cultivated types of Perilla crop and their weedy types in Korea and Japan.