• Journal of Korean Physical Therapy Science
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• v.9 no.3
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• pp.107-119
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• 2002

Astrocyte, which shares the greatest part of the brain (about 25%), is a land of glial cell that composes the central nervous system along with microglia, ependymal cell and oligodendroglia. It has 7-9nm of fibers in its cytoplasma, which are composed of glial fibrillary acidic protein (GFAP) and vimentin. As for the functions of the astrocyte, it has, so far, been supposed that the astrocyte will play a cytoskeletal role in maintaining the structure of the cerebrum, play a role as a blood-brain barrier so that it can induce migration of the neuron in its development and substances in the blood cannot go into the nervous tissue, and a role of immunology and phagocytosis. However, it was revealed today that it will be a role in preventing expansion of injury by attaching itself to the connective tissue such as the vessel and the pia mater when the nervous tissue or the arachnoid is injured. Microcurrent stimulation can control current, on the basis of A unit. That is, with such devices using it, it is possible to sense, from the outside, the injured current(wound current) of the lesion and to change it into the normal current, thereby promoting the restoration of the cells. In order to examine the effects of microcurrent stimulation on the injured astrocytes in the rabbits, this study was conducted with 24 New Zealand White Rabbit as its subjects, which were divided into 8 animals of the experiment group and 16 animals of the control group. After the animals in the experiment group were fixed to the stereotaxic apparatus, their hair was removed and their premotor area(association area) perforated by the micro-drill for skull-perforation with the depth of 8mm from the scalp. In one week after the injury, 4 animals in the control group and 8 animals in the experiment group were sacrificed and examined with immunohistochemical method. And in three weeks, the remaining 4 animals in the control group and 8 animals in the experiment group were also sacrificed and examined with the same way. The conclusion has been drawn as follows : In the control group sacrificed in one week after the injury, the astrocytes somewhat increased, compared with the normal animals, and in the group sacrificed in three weeks after the injury, they increased more (p < 0.05). The experiment group A in one week showed a little increase, but there was no significant differences, but the experiment group in three weeks showed more increase, compared with the experiment group in one week (p < 0.05). The experiment group B in one week showed more increase than the control group or the experiment group A, and the experiment group in three weeks showed more increase than the experiment group in one week (p < 0.05). Among the astrocytes, fibrous astrocytes were mostly observed, increasing as they are close to the lesion, and decreasing as they are remote from it. The findings show that microcurrent can cause the astrocytes to proliferate and that it will be more effective to stimulate the cervical part somewhat remote from the lesion rather than to directly stimulate the part of the lesion. Thus, microcurrent stimulation can be one of the methods that can activate the reaction of astrocytes, which is one of the mechanism for treating cerebral injury with hemorrhage. Therefore, this study will be used as basic research data for promoting restoration of functions in the patient with injury in the central nervous system.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.309-314
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• 2009

Incidence of rice stripe disease, caused by Rice stripe tenuivirus (RSV), was surveyed during 2002 to 2004. The incidence area and ratio of diseased fields were decreased gradually during those period. Rate of diseased plants were 45.8%, 45.0% and 43.7% in the susceptible cultivars Chucheong, Saechucheong and Ilpum, respectively. However, the rate was 4.4% in resistant cultivar Hwaseong. In addition, breakdown rate was also significantly high in the susceptible cultivars in Chucheong, Saechucheong and Ilpum showing 33.6, 33.2 and 31.9%, respectively. In Hwaseong, the breakdown rate was 0.8%. Collection efficiency was compared between two insect vector collection methods. Insect-sucking machine method was much more efficient than sweeping net method in collecting small brown plant hopper (SBPH). According to the survey of the population density of the insect vector during 2002 to 2004, the national average population density was gradually decreased year by year, 3.6, 2.3, and 1.3%, respectively. This result was significantly related with the decrease of the incidence of rice stripe disease. Control efficiency of rice stripe disease by treating several seedling box and water surface with insecticides against SBPH resulted that imidacloprid GR, Fipronil FG, Clothianidin+Probenazole GR and Thiamethoxam GR showed over 80% of control efficiency at 28 days after treatment at the early stage in nursery.

• Journal of the Korean Society of School Health
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• v.7 no.1
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• pp.45-55
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• 1994

The purpose of this study is to contribute to improvement of educational environment by analysing all problems related to environment around the school. To accomplish this purpose, this study was carried out by examining the problems in controlling the areas required for cleanup with 220 teachers in charging the cleanup duties of the primary and secondary schools in Taegu between June 1 and July 15, 1993 and by actually surveying the prejudical business stores around 72 primary schools between August 10 and September 20, 1993. Although most teachers answered to the questionnaires that it is necessary to cleanup the bad environment around the school, the duties of its cleanup tend not to be considered as an important matter. The teachers considered that the most prejudical business store around the school is totally the game room, and in such order as comic books' store, liquor selling shop and causing noise and pollution. 57.3% of total respondents answered that the present cleanup movements have resulted in failure mostly because of both supervising authorities' careless promotion and store owners' excessive commercial transactions. The result of actual survey in environmental and sanitary cleanup area around 72 primary schools showed that the greatest number of 1,258 prejudical stores was the video tapes shop, and then in such order as lodgings, and game rooms, while the number of prejudical store by the schools was 17.5 stores per school on the average which showed a various distribution from zero to 77 places. In general, these prejudical stores were mainly located around the schools in Jung-gu and Seo-gu areas. In addition, it was shown that the more the number of students, the more the number of the prejudical stores. In order to improve the environment around the school, it is necessary to strictly carry out the zoning system relating to the usage of land, to strongly restrict the stores without permit and abnormal stores and to establish the basis asking the city development authorities to go through the environmental evaluation. Moreover, it is absolutely required to make efforts to establish the national right sense of education, and to closely cooperate with the related authorities.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.698-703
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• 2012

This survey was conducted to obtain basic data of the quality of groundwater for agriculture in Gyeongnam province. Groundwater samples from paddy 15, upland 15, and plastic film house 30 sites were collected on April, July, and October in every two years from 2002 to 2008. According to the result of water quality analysis, groundwater quality was suitable for irrigation purpose averagely. The $NO_3$-N contents by land use were in the order of plastic film house > upland > paddy field and its contents were 6.53, 4.80, and $3.68mg\;L^{-1}$, respectively. In annual changes of water quality, pH was no significant change in paddy, upland, and plastic film house by 6.6~6.9. EC was increased in upland and plastic film house in 2008 and majors factors were $NO_3$-N and $Cl^-$. In upland and plastic film house, $NO_3$-N contents were 4.72 and $6.52mg\;L^{-1}$ in 2002, respectively, whereas they were 5.63 and $8.70mg\;L^{-1}$ in 2008, respectively. Of the investigated sites, $NO_3$-N was exceeded water quality standards for agriculture by 3.3~15.0% in plastic film house and $Cl^-$ was exceeded water quality standards for agriculture by 2.2% in upland of 2004. The $NO_3$-N contents were decreased with well depth and their contents were $5.38mg\;L^{-1}$ from 3~10 m, $4.87mg\;L^{-1}$ from 10~20 m, and $2.58mg\;L^{-1}$ from above 30 m. The $NO_3$-N contents by soil texture were highest in sandy loam by $5.73mg\;L^{-1}$ and lowest in clay loam by $4.13mg\;L^{-1}$. The $NO_3$-N contents by crops category were in order of fruit vegetables > leaf vegetables > rice > fruits > beans, contents of fruit vegetables and leaf vegetables were 5.81 and $5.30mg\;L^{-1}$, respectively.

• Journal of Korean Society of Forest Science
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• v.24 no.1
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• pp.1-24
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• 1974

A national programme of erosion control for soil and water conservation needs to be based on factual information about rates and quantities of soil erosion and of water runoff. The best and simplest way of reducing sedimentation pollution is to prevent or control the erosion at its sources. Steeply sloping earth banks are liable to both surface erosion and land-slides and the key to the control of these form of erosion lies with drainages and dense vegetation establishment including surface mulching on the slopes. Micro-plots having $1.6m^2$ (1 metre in width and 1.6 metres in slope length, and 1:1.2 in gradient) of banking slopes on the coarse sand soil are used to establish the order of magnititude of the difference in controlling of soil erosion and water runoff, and in potentiality of execution in consideration of the values of landscapes, performed on the 2 repetetions of six-experiment plots consisted of five surface mulches including seedings and one bare slope as a control treatment. The main results obtained may be summarized as follows: 1. The significant difference is realized in the quantities of soil erosion between the measures of six treatments. 2. Excepting the differences between treatment III and VI, the significant difference is realized in the rate of surface runoff between each treatment measures. 3. Both measures of treatment II and IV are recognized as the most effective measures in controlling the soil erosion and water runoff and also in establishing the ground vegetation. (Treatment II is a measures of the coarse straw-mat mulchings on the micro-strip seedings, Treatment IV is a measures of the "SPRAY-ON method" on the micro-strip seedings). In consideration of the potentiality of execution as well as the value of landscapes, the measures of treatment II could be recommendable for establishing the vegetation cover on the denuded gentle slopes in hillsides while the measures of treatment IV could be suitable for accelerating the establishment of vegetation on steeply sloping earth banks and cuts.

• Journal of Korean Society of Forest Science
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• v.28 no.1
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• pp.50-66
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• 1975

Since it is an undeniable fact that the so-called illegal field-burning cultivation is directly implicated in the causes of forest devastation, land erosion, and drought and flood, thus, barring the nation from a well-balanced economic growth, the policy to exterminate its practices must have the topmost priority. Eighty percent of Gangweon-do is mountain forests and naturally of all others this province has the largest area of illegally burned hill-side farminglands, stubbornly retarding the provincial development policy as well as directly causing tremendous forest damages. In 1965 a 7-year plan mapped out to rehabilitate these gypsy type field burning farmers only to be suspended in 1968 to give way to the mandatory project of clearing the isolated farmsteads set in deep mountain to circumvent the guerilla forces signaled by the so-called Samcheok-Uljin area infiltration. In the meantime, new hordes of roving farmers burned the forests, working a renewed havoc. To cope with this situation, the provincial government, taking the year 1973 as a planning year, launched another three year project (1974-76) and has been enforcing the rehabilitation project mobilizing the whole administrative power. Whether or not this project will succeed solely depends upon whether the forcedly rehabilitated roving farmers can really establish self-supporting homesteads. Among the various difficulties facing the newly established homesteaders are: (1) First of all, the homesteaders must be given money-earning jobs. (2) Financial supports or subsidies must be provided them with which to establish self-supporting homesteads. (3) Private enterprises as well as public organizations must offer them jobs with priority. (4) The rehabilitated rovers themselves must establish self-supporting homesteads before expecting the external assistance. (5) The rehabilitated rovers themselves must have the spirit of self-help, welcoming all levels and all kinds of jobs. (6) The rural revitalization movement must expand the self-help reconstruction projects to give them the opportunity to work. (7) All citizen in the province must receive and protect them with brethren love. (8) The evacuated burned-forests must be reforestrated with the principle of "best trees to the best lands". (9) The seedlings of species that the forest owners select must anyhow be secured and supplied (10) The organization and function of the village forestry association must be strengthened to take effective care of the reforestated burned-forests.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.1-7
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• 2005

Tidal flats have been regarded to carry out transformation and removal of land-derived organic matter, and this purifying capability of organic matter by tidal flats is one of very important reasons for their conservation. However, integral biogeochemical studies on production and decomposition of organic matter by benthic microbes in tidal flats have been absent in Korea, although the information is indispensable to quantification of the purifying capability. Our major goals in this multidisciplinary research were to understand major biogeochemical processes and rates mediated by diverse groups of microbes dominating material cycles in the tidal flats, and to assess the contribution of benthic microbes to removal of organic matter and nutrients in the tidal flats. Our study sites were Ganghwa and Incheon north-port tidal flats that had been regarded as naturally well reserved and organically polluted, respectively. Our research group measured over 3 years primary production, biomass and community structure of primary producers, abundance and production of bacteria, enzyme activities, distribution of protozoa and protozoan grazing rates, rates of denitrification and sulfate reduction, early sediment diagenesis, primary production and respiration based on oxygen microelectrode. We analyzed major features of each biogeochemical process and their interactions. The results are compiled in the following articles in this special issue: An (2005), Hwang and Cho (2005), Mok et at. (2005), Na and Lee (2005), Yang et at. (2005), and Yoo and Choi (2005).

• Journal of Animal Environmental Science
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• v.8 no.1
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• pp.9-16
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• 2002

This study was conducted to develope the new solid separating system which can be efficiently and economically removed the solid parts in high pollutants concentration of pig slurry. The pollutants concentration, BOD$_{5}$ , COD and SS of the slurry used in this study was 15,990($\pm$2,389)mg/l, 20,004($\pm$5,512)mg/l and 26,486($\pm$5,935)mg/l, respectively. After removal of solid part in slurry, the pollutants concentration, BOD$_{5}$, COD and SS was change into 5,617($\pm$690)mg/l, 5,553($\pm$633)mg/land 1,456($\pm$341)mg/l, respectively in the Fixed biological membrane tank. The reduction of the pollutants concentration of suspend liquid through membrane will be allowed to greatly improve the water purification by an Activated sludge method. This separating system consisted of a temporary storage, a circulating tank and a Fixed Biological membrane tank. A temporary storage which has a draining system of screw type and an aeration device played a tremendous role in draining the solid by filled an aeration of 0.3 l/min. A Fixed Biological membrane tank of which a styrofoam filled in a 2/3 volume as a Biological media was fixed by a stainless steel net (pore size : 0.5mm) to separate the liquid layer of influx in them. The separating system efficiency factors were the speed of screw motor, cycle number of slurries in a circulating tank and moisture contents of solid effluent through the screw path. Although the pollutants concentration was very variable in temporary storage, the final concentration of $BOD_5$ and SS, except COD of the suspended liquid in a Fixed biological membrane were not different regardless of cycle number of a circulating tank. Moisture contents of effluent from temporary storage was 73% under the speed 1 ppm of screw motor and 62% under the 1/4rpm of it.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.10-10
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• 2017

Rice consumption has been continuously decreasing as the eating habits of Koreans have become westernized and diversified. The per capita annual rice consumption in Korea has dropped sharply from 136.4 kg in 1970 to 61.9 kg in 2016. The Korean government, therefore, has been trying to promote rice consumption by invigorating the processed food industry using rice flour. To facilitate the market for processed rice foods, it is essential to develop proper milling technology in terms of flour particle size and damaged starch content to produce high quality rice flour at competitive cost. Dry milling and wet milling are the two major processes used to produce rice flour. Although the dry milling process is relatively simple with a lower production cost, damaged starch content increases because of the high grain hardness of rice. In wet milling, the quality of rice flour is improved by reducing flour particle size as well as damaged starch content through soaking procedures. However, the production costs are high because of the additional expenses associated with the disposal of waste water, sterilization and drying of the wet flour. Recently developed technologies such as jet milling and cryogenic milling also require expensive investment and production. Therefore, developing new rice cultivars with dry milling adaptability as well as good processing properties is an important goal of rice breeding in Korea. 'Suweon 542' is a floury endosperm mutant line derived from sodium azide treatment on a high-yield, early maturing, and non-glutinous japonica rice cultivar, 'Namil'. Compared with the wild type, after dry milling process, the grain hardness of 'Suweon 542' was significantly lower because of its round and loosely packed starch granules. Also, the flour of 'Suweon 542' had significantly smaller particles and less damaged starch than 'Namil' and other rice cultivars and its particle size distribution was similar to a commercial wheat cultivar. Recently, through collaborations with nine universities and food companies, a total of 21 kinds of processed prototypes, using the dry milling flour of 'Suweon 542', were evaluated. In the production of major rice processing products, there was no significant quality difference between the flours prepared by wet milling and dry milling. Although the amount of water added to the dough was slightly increased, it was confirmed that the recipe applying the wet flour could be used without significant change. To efficiently transfer the floury endosperm characteristics of 'Suweon 542' to other commercial rice cultivars, it is essential to develop DNA marker tightly linked to the target gene. Association analysis using 70 genome-wide SSR markers and 94 F2 plants derived from 'Suweon 542'/'Milyang 23' showed that markers on chromosome 5 explained a large portion of the variation in floury grains percentage (FGP). Further analysis with an increased number of SSR markers revealed that the floury endosperm of 'Suweon 542' was directed by a major recessive locus, flo7(t), located in the 19.33-19.86 Mbp region of chromosome 5, with RM18639 explaining 92.2% of FGP variation in the F2 population. Through further physical mapping, a co-segregate and co-dominant DNA marker with the locus, flo7(t) was successfully developed, by which, thereby, breeding efficiency of rice cultivars having proper dry milling adaptability with high yield potential or useful functional materials would be improved. 'Suweon 542' maintained the early maturity of the wild type, Namil, which can be used in rice-wheat double cropping systems in Korea not only for improved arable land but also for sharing flour production facilities. In addition to the high susceptibility against major rice diseases, nevertheless, another possible drawback of 'Suweon 542' is the high rate of viviparous under prolonged rainfall during the harvesting season. To overcome susceptibility and vivipary of 'Suweon 542', the progeny lines, derived from the crosses 'Suweon 542' and 'Jopyeong', an early maturing rice cultivar with multiple resistance against rice blast, bacterial blight, and rice strip virus, and 'Heugjinju', a anthocyanin pigment containing black rice cultivar, were intensively evaluated. As the outputs, three dry milling suitable rice elite lines, 'Jeonju614', 'Jeonju615', and 'Jeonju616' were developed.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.3 no.3
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• pp.45-76
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• 2000

The purposes of this study were to investigate and understand the present status of various types of "deserts", such as sand desert, gravel desert, rock desert, earth desert, salt desert, desert, rocky desert, gobi desert, sandy desert, clay desert, etc., and the general countermeasures for the combating "desertification" "desertization", and to develop the technologies on the revegetation and restoration for the combating desertification in China. The methods of this study were mainly composed of field surveys on the several experimental sites and research institutes related to combating desertification in China, and examinations on the various technologies for the combating desertification at the Daxing Experimental Station of Beijing Forestry University. The conclusion from this study may be summarized as follows; 1. Status and tendency of desertification in China : China is one of the countries seriously threatened by desertification. Desertification affected areas in China are mainly distributed in arid, semi-arid and dry sub-humid areas in China, covering the most regions of the Northeast China (eastern region of Inner-Mongolia), the northern part of the North China (middle and western region of Inner-Mongolia, Shaanxi, Ningsha, Gansu) and the western part of the Northwest China (Xinzang, Qinghai, Xizang). The total area affected by desertification in China is approximately 2.622 million $km^2$. It covers 27.3% of the total territory of China. Until recently, it is estimated that the annual spreading ratio of desertification in China is 2,460 $km^2$. Therefore, desertification is mostly serious problems facing to the Chinese people. 2. The causes and environmental effect of desertification : The desertification in China is mainly caused by compound factors, including natural condition and human activities. In China, the desertification is started by the decrease of precipitation, continuous dry and drought, strong wind, wind and water erosion, land degradation and loss of natural vegetation caused by climate variation, and accelerated by the human activities, such as over-cultivating, over-grazing, over-cutting of woods, irrational use of water resources. Because desertification has affected the geographical features, soil nutrients contents, salinity, vegetation coverage and the functions of ecosystem, the environmental deteriorations in the desertification affected areas are very seriously. 3. The fundamental strategies of combating desertification in China are the increase of education and awareness of people through various mass media, the revision of laws to guarantee operation of Desertification Combating Law and to improve many relating laws and regulations, the application of advanced technologies and training of experts, the establishment of discriminative policies, and increasing arrangement of budget-investment, and so on. China, as a signed country in UNCCD, has made efforts for the combating desertification. Korea is also signed country in UNCCD, so we should play an important role in the desertification combating projects of China for the northest asia and global environmental conservation as well as environmental conservation of Korea.