• Journal of Microbiology and Biotechnology
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• v.24 no.7
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• pp.888-897
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• 2014

A bacterial community analysis of the gut of Tenebrio molitor larvae was performed using pyrosequencing of the 16S rRNA gene. A predominance of genus Spiroplasma species in phylum Tenericutes was observed in the gut samples, but there was variation found in the community composition between T. molitor individuals. The gut bacteria community structure was not significantly affected by the presence of antibiotics or by the exposure of T. molitor larvae to a highly diverse soil bacteria community. A negative relationship was identified between bacterial diversity and ampicillin concentration; however, no negative relationship was identified with the addition of kanamycin. Ampicillin treatment resulted in a reduction in the bacterial community size, estimated using the 16S rRNA gene copy number. A detailed phylogenetic analysis indicated that the Spiroplasma-associated sequences originating from the T. molitor larvae were distinct from previously identified Spiroplasma type species, implying the presence of novel Spiroplasma species. Some Spiroplasma species are known to be insect pathogens; however, the T. molitor larvae did not experience any harmful effects arising from the presence of Spiroplasma species, indicating that Spiroplasma in the gut of T. molitor larvae do not act as a pathogen to the host. A comparison with the bacterial communities found in other insects (Apis and Solenopsis) showed that the Spiroplasma species found in this study were specific to T. molitor.

• Journal of Environmental Science International
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• v.27 no.2
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• pp.123-133
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• 2018

The historical exchanges between the Republic of Korea and Japan have broadly occurred, in terms of both political and cultural aspects, from ancient to modern times. Regarding ancient gardening culture, in particular, Asuka developed gardens with the gardening techniques passed down by the Baekje people. The development of the basic form of a garden pond along with its characteristics, established through such exchanges, is suggested by investigating its components through analysis of data from the gardens of Baekje and Asuka. In terms of the garden pond structure, homogeneity was confirmed between Baekje and Asuka, with a linear rectangular form as the basic design. In addition, the vertical construction technique was used by both ancient kingdoms. In terms of the types of stone used in building the shore of the garden pond, Baekje used diverse types such as natural stone, crushed stone, and cut stone. In contrast, rounded river stone was used by Asuka. Regarding the floor of the garden pond, Baekje used soil, which enabled the planting of lotus flowers. In contrast, Asuka used stones to pave pond floors, which made the growth of plants impossible. In terms of layout, Baekje used ornamental stones for pond landscaping, while Asuka used manmade island and water intake facilities in their pond construction. The effects of Baekje's garden culture on Asuka's garden building can be seen from its influence on the form of the garden pond and shore construction style. In terms of the construction of the garden pond's shore with the same stones and the stone flooring, the garden ponds of the Asuka Kingdom reveal technically unified and refined aspects.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.79-82
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• 2003

대부분의 신 간척지 논은 점토 함량이 적은 반면 미사 함량이 많고 토양 콜로이드의 분산제 역할을 하는 Na함량이 높기 때문에 이러한 토양은 입단화가 저해되고 투수성이 불량해 진다. 이러한 투수와 더불어 다량의 SiO$_2$, F$_2$, MR, MgO 등이 하층으로 용출되어 투수성과 통기성을 저하시키고 간척지 토양의 토양 물리화학적 불량에 의한 저수확답의 원인의 되어 벼의 재배가 어렵고 생산성이 낮아 경제성을 기대하기 어렵다. (김, 1992 : 고건, 1988 ;단야, 1983 ; 전중등, 1974). 따라서 본 실험에서는 토양의 염분농도차이가 토양화학성과 수량에 미치는 영향을 검토하여 간척지 토양의 경제성을 높이는데 기초자료로 활용코자 시험한 결과는 다음과 같다. 1. 출수기는 0.1%의 염분농도 토양은 8월15일, 0.4%의 염분농도 토양은 8월 20일, 0.8%의 염분 농도 토양은 8월 25일로서 0.1%의 염분농도 토양이 가장 빨랐다. 2. 쌀수량은 토양의 염분농도가 0.1%로 낮은 토양이 599kg/10a로 가장 많았고, 다음으로는 0,4%의 염분농도 토양이 568kg/10a이었고 0.8%의 염분농도 토양은 446kg/10a로 가장 낮았으며 쌀수량 구성요소 역시 같은 경향으로 0.1%의 염분농도 토양에서 가장 우수하였고 다음으로는 0.4%, 0.8%순으로 나타났었다. 3. 쌀수량과 토양의 이화학적 특성간의 상관에서는 pH와는 부의 상관, 유기물, 인산, 질소, 가리, 칼슘, 마그네슘의 함량간에는 정의상관이있다. 4. 전남광양만 간척지에서 쌀수량과 수량 구성요소면에서 볼때에 적합한 토양의 염분농도는 0.1%이라고 사료된다.

• The Korean Journal of Ecology
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• v.24 no.4
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• pp.233-237
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• 2001

Changes of the oribatid mite species composition during the litter decomposition was investigated in the north-facing and south-facing slopes with different lower vegetation (annual herbaceous plants in north and perennial Sasa in south) in the altitude 1,000 m of Mt. Jumbong, a nature reserve area in Korea, from August 1994 to September 1995. Total 58 species of oribatid mites were collected. The values of O1son's negative exponential index (k) were -0.56 in the south-facing slope and -0.49 in the north-facing slope, but there was no significant difference between them. The decomposition rate of litter increased rapidly until Oct. 1994, and decreased thereafter. Intensive settlement of the forest litter by oribatid mites was recorded in the autumn periods and it decreased in the next spring and summer. Species diversity index (H'), and species evenness (J') ranged from 1.74 to 2.69, and from 0.57 to 0.93, respectively, and the values were lowest in spring. In the successive periods of growing season, there followed great changes in the structure of species dominance. Heminothrus minor was one of the most dominant species in autumn in the first year when litter were placed, but was never recovered next seasons. In contrast, Platynothrus yamasakii was also dominant in the first autumn, then decreased very low in numbers in next spring and summer, but regained its number in autumn. On the other hand, an increase of the number during these periods was observed by Epidamaeus sp.2. Ceratopia bipilis and Epidamaeus sp.1 were abundant both in the north-and south-facing slopes. Trichogalumna nipponica was only found in the south-facing slope, and Nanhermannia elegantula was only found in the north-facing slope.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.187-194
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• 1992

Rhizopus oryzae CJ-2114 was selected for its strong polygalacturonase activity among various strains of mold found in soil. It was found that the production of polygalacturonase reached to maximum when the wheat bran medium containing 1% albumin, 1% sorbitol and 0.2% (NH$_4$)$_2$C$_2$O$_4$was cultured for 96 hrs at 3$0^{\circ}C$. Polygalacturonase was purified 11.13 fold from Rhizopus oryzae CJ-2114. The purification procedures include ammonium sulfate treatment, gel filtration on Sephadex G-75, G-150 and DEAE-cellulose ion exchange chromatography. Yield of the enzyme purification was 40.3% .Purified enzyme was confirmed as a single band by the polyacrylamide gel electrophoresis. When the purified enzyme was applied to SDS-poly-acrylamide gel electrophoresis, the molecular weight was estimated to be 47,000. The amino acid composition indicated relatively high contents of glutamic acid and glyrine.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.4
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• pp.61-69
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• 2002

This study was conducted to develop revegetation methods for the restoration of the steep slopes by seed attached ripping net revegetation methods. In general, steep slopes with decomposed granite soils and ripping rock are easy to erode by precipitation and impossible to revegetate only using hydroseeding with core net mulching because of poor soil fertility. The Seed Attached Ripping Net Revegetation Methods(SALNRM) will be the most popular and sustainable methods to restore decomposed granite soils and ripping rock exposed slopes. The main results are summarized as follows; 1. The net size with $1.5cm{\times}1.0cm$ density was more suitable for growing plants, and increasing the ratio of the slow release fertilizer was better to make early coverage and to grow germinated plants. 2. The fertilizer bag made by the ratio of Peatmose : Vermiculite : Perlite : Quick release fertilize r : Slow release fertilizer = 10 : 2 : 5 : 3 : 4 (v : v) was the best for plant's growth. 3. According to the seed mixture experiments, even though not using foreign grasses, the SALNRM using native plants can make diverse plant composition. 4. The SALNRM will make same early ground coverage by only using native plants like using foreign grasses. The SALNRM would become the popular revegetation methods to restore decomposed granite soils and ripping rock exposed slopes in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.95-101
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• 2002

To investigate the changes in the composition and pool size of nitrogen metabolites under drought stress, white clover (Trifolium repens L.) were exposed to -0.04MPa (well-watered, control) or to -0.12MPa (drought-stressed) of soil water potential during 28 days. Dry weight of leaves in drought-stressed plants was remarkably decreased by 45% and 74% within 14 days and 28 days, respectively, compared with control. For nitrate concentration after 28 days of treatment, a significant difference (1.6 times higher in drought-stressed plants) was observed only in stolon. NH$_3$-NH$_4$$^{+}$ concentration in all three organs of drought-stressed plants linearly increased to more than 1.6 times higher level at 28 day when compared to the initial level (day 0), while the increasing rate in control was much less than that of drought-stressed plants. Proline concentrations in drought-stressed plants remarkably increased and reached to 7, 13 and 17 times higher level at 28 day compared to control. Protein concentration in leaves of drought-stressed plants tended to decrease, while it slightly increased during the first 14 days and reached a plateau afterward in control. There was not significant difference in the proteins concentration of stolon and roots throughout experimental period. On SDS-PAGE analysis, two major proteins specifically induced by drought stress (16-kD and 18-kD) were detected in stolon.n.

• Applied Biological Chemistry
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• v.32 no.3
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• pp.309-314
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• 1989

The cultural condition of Enterobacter agglomerans U-1, a polysaccharide producing soil bacterium, was examined. The optimal medium composition was that contains the following components per liter of distilled water; $sucrose(23.75\;g/L),\;peptone(2.06\;g/L),\;yeast\;extract(0.5\;g/L),\;KH_2PO_4(1.0\;g/L)$ and $MgSO_4{\cdot}7H_2O(1.0 g/L)$. The optimum temperature for polysaccharide production was $30^{\circ}C$, where 8.5 g/L of polysaccharide was produced. The apparent viscosity of fermentation broth after 3 days was 240 mPa.s. at $70sec^{-1}$. The product yield and specific productivity were 36% and 142.07 mg/g/h.

• Journal of Forest and Environmental Science
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• v.27 no.2
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• pp.93-99
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• 2011

In this study, a total of 350 households contained 700 individuals in Iganzo village were surveyed to study their literate and poverty levels and their impacts to conservation of the Mbeya Range Forest Reserve. The study included 350 women and 350 men. The majority of respondents were between the ages of 31-40 years old (53%), while the rest were between 41-50 years old (25%) and 21-30 years old (22%). The total income per day per household was calculated and averaged to 4,570 Tanzanian shillings that is equal to about 3 U.S. dollars. The average number of members per household was seven. It was reported that, there is a tremendous decrease in biodiversity composition of the reserve mainly due to poverty (80%) and ignorance (76%) of the people on the importance of the reserve. Other causes for this decrease were reported to be grazing of livestock in the reserve (23%), poor farming systems (68%), which resulted in soil erosion, encroachment (64%) through expansion of farms towards the reserve boundary and charcoal burning (34%). Respondents from Mbeya Urban Water Supply Authority and District Forest Office mentioned lack of funds (49%) and lack of experts (56%) as challenges that face the conservation of the reserve. It was revealed that 25% of respondents had never gone to school, 53% had primary level of education as their highest level of education, 20% had secondary education and 2% had first degree. The null hypothesis that poverty and illiteracy have a positive correlation to forest degradation was accepted based on these findings at a probability of p>0.85. Thus, it was concluded that poverty and illiteracy among Iganzo village residents are the main causes for the degradation of biodiversity in Mbeya Range Forest Reserve.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.5
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• pp.523-531
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• 2021

In general, the foundation refers to a group pile with several single piles connected by an upper structure. However, when a load is applied to pile groups, the range of stress applied to the ground is expanded and overlapped compared with the single pile, so the overall bearing capacity may decrease. This reduction ratio of bearing capacity is referred to as the efficiency of pile groups. Therefore, in this study, the soil composition, the arrangement and spacing of group piles, and the contact characteristics between the ground and piles were set as analysis variables, and the group pile efficiency and individual pile behavior were analyzed. As a result of the analysis, the efficiency of pile groups tends to converge or decrease when the friction coefficients are increased with ground type. Through this, the optimal efficiency of pile groups can be derived. In addition, through the analysis of individual piles, the load ratio of each pile was analyzed when an upper load was applied. In the case of piles located inside group piles, the load was relatively low, and this is considered to have an influence on the internal ground.