• Journal of Life Science
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• v.15 no.6 s.73
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• pp.889-894
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• 2005

This experiment was carried out to investigate the effects of simulated acid rain (SAR) in the shoot growth and internal structure of Arabidopsis thaliana. In the shoot growth, the plants treated with SAR (pH 3.0) for 15 days showed no morphological change compared to the control plants. Some change was observed in the internal structure of the stems: the epidermis and cortex tissues of the stems treated with SAR were partly damaged. The plants treated with SAR showed no noticeable difference compared to the control plants, but morphological changes were observed in the leaf. The leaves of the plants treated with SAR showed many white necrotic spots on the part of upper epidermis. A light microscopic examination of the leaves with necrotic spots showed that the upper epidermis was severely compressed with the damaged cuticle layer and the mesophyll cells were also damaged and compressed. However, noticeable structural change of vascular bundle cells was not observed.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.205-209
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• 2023

Mechanical stimulation induce the morphological changes in plants. In this study, we investigated the growth changes of tomato seedlings applicated to mechanical stimulation. The brushing treatment was used for mechanical stimulation. The brushing treatment interval was 2 hr using transfer device attached acrylic film from 10 days after sowing. Growth parameter of tomato seedlings were measured 3-day intervals to investigate the growth changes during brushing treatment. The plant height and leaf area were decreased in brushing treatment than the control, and the fresh and dry weights of shoot didn't have significant difference in the control and brushing treatment. The total root length and root surface area were increased in brushing treatment compared than the control, and root volume has no significant difference in the control and brushing treatment. In conclusion, these results suggest that the application of brushing treatment on tomato seedling make shorten plant height and well-development root morphological characteristics.

• Journal of Oral Medicine and Pain
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• v.26 no.3
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• pp.205-214
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• 2001

오늘날 스트레스라는 단어는 모든 현대인과 방송, 언론매체에서도 매일 거론되어질 정도로그 중요성이 대두되고 있다. 의학계에서도 스트레스를 단순한 심리적 문제로 국한시키지 않고 과도한 스트레스가 지속될 경우 신경계와 내분비계, 면역계의 변화를 초래해 인체의 항상성에 영향을 미쳐 질병을 일으킨다는 것을 인식하고 있으며 이에 대한 연구가 진행되고 있다. 이러한 질병의 발생과정에서 생체의 일부조직이 파괴됨으로써 기능과 형태변화가 초래될 때 apoptosis가 관여하고 있으며 이에 본 저자는 스트레스와 구강악안면영역에서 발생할 수 있는 질병과의 상관관계를 규명하기 위해 이종의 한냉 스트레스와 다소의 굴신을 허용한 중등도의 구속 스트레스를 부여한 후 측두하악관절 활막의 변화를 전자현미경관찰을 통해 밝혀내고자 한다. Sprague-Dawley계 웅성 백서(200-230 g/bw) 33마리를 구속스트레스부여군 (12마리), 한냉스트레스부여군 (12마리) 및 정상군 (3마리)으로 나누고 이들을 각각 구속장치에 구속한 후 1, 3, 5, 7일에 각각 희생시켰으며 측두하악관절 활막의 변화를 전자현미경으로 관찰하였다. 그 결과는 다음과 같다. 1. 중등도의 구속스트레스군에서 사립체는 부분적으로 농축된 소견을 보였으며 수와 크기에 있어 시간이 지남에 따라 점차 감소하는 소견을 보였다. 2. 중등도의 구속스트레스군에서 과립내형질망은 점점 확장되었으며 불규칙한 형태를 나타내었다. 3. 중등도의 구속스트레스군에서 물결모양의 핵막의 이중구조가 7일군에서 관찰되었다. 4. 한냉 스트레스군에서 사립체는 1일, 3일군에서 약간 부푼 형태를 가지고 그 수가 다소 감소되었으나 시간이 지남에 따라 5일, 7일군에서 건강한 모양으로 점차 증가되었다. 5. 한냉 스트레스군에서 과립내형질망은 1일, 3일군에서 불규칙하게 확장된 소견을 보였으나 5일, 7일군에서는 잘 발달된 형태로 핵 주위에서 다수 관찰되었다. 6. 한냉 스트레스군에서 핵은 전 기간에 걸쳐 큰 변화를 보이지 않았다. 이와 같은 결과를 토대로 측두하악관절 활막조직은 한냉 스트레스 및 중등도의 구속 스트레스에 대하여 중등도의 저항성을 가지고 있는 것으로 생각되며 생리적 적응한계를 넘는 과도하고 지속적인 스트레스에 의하여 활막조직이 apoptosis되어 측두하악관절에 병리적 변화를 초래할 가능성이 있다고 사료되어 이후 지속적인 연구가 요구된다.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.1
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• pp.111-120
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• 2014

Purpose: This study was to investigate changes in the thickness of cornea, curvature of cornea, and aberration depending on the water contents, materials, and refractive power of contact lens. Methods: The differences in the corneal thickness between pre- and post-wearing the lenses were compared using 5 kinds of lenses. The changes in the corneal thickness, the curvatures of the anterior and posterior cornea, and high order aberration (HOA) before and after wearing the lenses were investigated at the center of the cornea, and the different distance and the direction away from the center of the cornea. For the equipments of measurement, ORB ScanII (Bausch & Lomb Inc, ver 3.14) was used to measure the corneal topography and thickness, and Zywave (Bausch & Lomb Inc, ver 5.20) was used to analyze the high order aberration. Results: Five (S1, S2, S3, T1, T2) of the lens was used for this study, excluding the lens T2 lens has four lenses and the thickness of the corneal shape, but the impact is minimal. In the case of the hydrogel soft contact lenses (T2 lens) with low oxygen permeability, the corneal thickness showed distinct increasing patterns. The high order aberration and coma aberration were most changed in the silicon hydrogel toric lens, while the depth of anterior was most changed in the hydrogel toric lens. Conclusion: Among the 5 kinds of contact lenses with different water contents, materials, and refractive power used for this study, the corneal shape change was small for the lenses with an oxygen permeability (Dk) of more than 28, and the largest for the lenses with a very low oxygen permeability.

• Journal of Korea Water Resources Association
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• v.52 no.2
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• pp.163-172
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• 2019

The linear and cross-sectional shapes of the natural river channel are subjected to continuous changes in time and space due to the interaction with the flow of water and sediment transport. This study aims to investigate the morphological characteristics and change patterns of river channel quantitatively for the middle reach of Nakdong River, which has undergone large scale riverbed dredging and construction work, as Four Major River Restoration Project. A series of bathymetry and near-river survey has been conducted to obtain the detailed terrain information for the study area. The properties related to the linear and cross-sectional characteristics of river channel have been calculated based on the filed survey data and analyzed with comparing the survey data obtained in 2012 for the project completion. Since there has not been enough time for meaningful terrain change to take place, it was not possible to extract special tendency in the degree and aspect of terrain change. However, it is necessary to make regular examinations to the patterns and degree of river channel change using the proposed methodology.

• Journal of the Korean association of regional geographers
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• v.13 no.3
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• pp.321-340
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• 2007

In this thesis we have examined the concrete forms and periodic tendency changes of eup-settlements, local administrative town, locations within 91 districts in 71 counties of Gyeongsang province. First of all, we have analyzed the overall conditions of eup-settlement locations in Joseon Dynasty under the criterion of topography, feng-shui, and scenery image of the mountains at the back. Then we looked into alterations of location forms mainly of the eup-settlement in which the exact time of migration can be identified and cities which have the evident dates of construction. To sum up, the result is as follows. Firstly, the concrete form of eup-settlement locations in Joseon Dynasty are usually built up in traditional ways, however, quite a few unconventional ones also existed. Secondly, the town castles constructed at the end of Goryeo Dynasty period and before 1430's are hardly related to the traditional location format of Joseon Dynasty, yet the ones constructed after 1430's were mostly in the typical location format. Thirdly, the old eup-settlements established before 1425 are scarcely in the typical location form of Joseon dynasty, but the new eup-settlement established after 1425 were mostly in the typical location forms.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.201-214
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• 1983

A study was undertaken on rats in order to clarify the gastric mucosal, morphologic response to oral and subcutaneous administration of acetylsalicylic acid(aspirin). Aspirin was administered orally (oral group) and subcutaneously (subcutaneous group) at does rate of 60 mg per kg of body weight per day to 40 normal rats. On the 1st, 3rd, 7th, and 15th day of administration, in addition to clinical observation, 5 rats each from the both groups were sacrificed and examined macroscopically, histologically and electron-microscopically for the morphological changes of gastric mucosal cells with the following results. Although the clinical, macroscopic and histological changes were not significant, marked ultrastructural changes were observed. Parietal and chief cells were affected most severely by the administration of aspirin ; parietal cells showed increase in the number of SER and intracellular canaliculi, where-as in chief cells fragmentation, luminal dilatation, decrease in the number and structural abnormalities of RER were seen. Relatively mild changes were observed in mucous, mucous neck and basal-granulated cells. Although the degree of changes was milder than those of oral group, the similar changes were also observed in the subcutaneous group. From these results, it would be concluded that aspirin injury of gastric mucosa is effected not only by the direct injury to the mucosa but also indirectly by the blood concentration of aspirin.

• Korean Journal of Environmental Agriculture
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• v.18 no.4
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• pp.378-383
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• 1999

Changes of the spectroscopic characteristics of the organic matter fractions and circular filter paper chromatograph were assessed for the bark and piggery manure composts during the composting. as an approach to base the criteria of the compost maturity evaluation. Contents of humic acid-C (HA-C) and fulvic acid-C (FA-C) in both bark and piggery manure composts were decreased as the composting got closer to maturity, but the ratios of HA-C/FA-C were increased. During the composting. ${\Delta}log$ K values were decreased, but RF values were increased. Humic acid of the mature bark compost after 120 days of composting was A-type, as compared to Rp-type for the raw bark and B-type for the immature compost. However. humic acid of the mature piggery manure composts after 40 days of composting was B-type, indicating the humification of the organic matter fractions continued at this stage. Circular filter paper chromatograph of the mature bark compost exhibited the regular sawteeth pattern at the edge, but that of the mature piggery manure showed an irregular sawteeth pattern. Results demonstrated that spectroscopic characteristics and circular filter paper chromatograph of the organic by-product composts might be employed for the compost stability assessment.

• Analytical Science and Technology
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• v.26 no.1
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• pp.106-112
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• 2013

PDE plays an important role in cAMP-mediated cellular signaling within the cells. The proper targeting of each PDE is mediated by unique N-terminal of each PDE isoform. It has been recently reported that supershort-, short- and long-forms of PDE4 in Aplysia were cloned in Aplysia. Long-form of ApPDE4 was localized at plasma membrane and presynaptic terminal in Aplysia sensory neurons. However, it remains elusive which part of ApPDE4 is minimal region for the proper targeting and what are the effects on the cell functions. Here, we identified that N-terminal 13 amino acids of ApPDE4 long-form is minimal regions for the plasma membrane targeting. In addition, overexpression of ApPDE4(N20)-mRFP could induce morphological changes in HEK293T cells. Interestingly, mRFP-$PLC{\delta}1$(PH), which selectively binds to PI4,$5P_2$, could induce morphological changes in similar with that by ApPDE4(N20)-mRFP. These results suggested that binding of ApPDE4(N20) to lipids including PI4,$5P_2$ might be responsible for targeting of ApPDE4 to plasma membrane and morphological changes in HEK293T cells.

• Journal of Bio-Environment Control
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• v.4 no.1
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• pp.32-42
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• 1995

Cultivation using rain shelter is very popular in summer because rain shelter has a simple structure using less materials than any other regular greenhouse. Although it has a main advantage of easy construction in terms of labour, time and cost, it has some disadvantage of poor ventilation and rain fall inflow. Therefore, the rain shelters being able to overcome the problems, to some extent, are necessary to propagate for practical purpose. Three characteristic types of rain shelter were analyzed using measured and simulated environment data. Type 1 was a conventional type with an arched roof, and Type 2 and Type 3 were improved ones which were designed to have three arched roofs and three sawtooth like roofs with the openings for ventilation, respectively. The distribution of inside temperature measured was relatively uniform in Type 2 and 3 by the natural ventilation through the openings of the roof compared to Type 1 which had no openings. The relative light transmittance measured in Type 2 and 3 showed lower than that in Type 1, which suppressed the rise of inside temperature, For more accurate comparison, the differences between inside and outside temperatures to various wind speeds were calculated by the model. The difference in Type 1 was the greatest at lower wind speed below 1 ㎧, that is, the highest in inside temperature, but decreased rapidly as wind speed increased above 1 ㎧. Measured temperatures generally showed the same trends as calculated ones by the model. As a whole, the improved rain shelters(Type 2 and 3) showed better performance than the conventional one in ventilation as well as inside temperature.