• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.371-378
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• 2009

This study was carried out to investigate the improvement effect of soil fertility by incorporation of GMC(green manure crops) at rice cropping after cultivation GMC such as the barley for alternative rye in paddy field over the past two years(2006~2007). Plots, which consisted of incorporation time of GMC as rye; heading stage, barley; heading stage, heading stage of rye and 10days after heading stage were divided by amount of applied rates; standard fertilizer fertilization, diagnosis fertilization and non-fertilization. we investigated change of soil physico-chemical properties, degree of decomposition on GMC in soil, growth and yield potential. The obtained results were summarized as follows. The fresh weight of GMC at incorporation time on heading stage of rye, heading stage and 10days after heading stage of barley were $2,715,\;2,352,\;2,867kg\;10a^{-1}$ respectively. Content of total nitrogen at three incorporation times was 1.31, 1.46, 1.38% and the C/N ratio were 33.4, 28.7, and 34.6, respectively. Some soil physical properties, such as soil hardness and bulk density tended to decrease with incorporation of GMC, while surface soil depth and porosity were increased. Some soil chemical properties, such as content of exchangeable cations and cation exchangeable capasity(CEC) were increased with incorporation of GMC compared with before experiment. Rice yields was increased 3~9% in diagnosis application plots on application of barley compared with control($559kg\;10a^{-1}$) and incorporation of barley caused to improve perfect kernel ratio 73.6~78.7% in appearance characteristics of brown rice compared with cotrol(73.0%). It was found that incorporation with 10days after heading stage of barley was more effective to reduce chemical nitrogen fertilizer and to improve soil fertility.

• Journal of Life Science
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• v.29 no.4
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• pp.402-409
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• 2019

Korean red ginseng made from steaming and drying fresh ginseng has long been used as a traditional herbal medicine due to its effects on the immune, endocrine, and central nerve systems and its anti-inflammatory activity. In this study, we investigated the molecular mechanism responsible for the anti-inflammatory effects of a formulated Korean red ginseng extract (RGE) in response to lipoteichoic acid (LTA), a cell wall component of gram-positive bacteria. RGE inhibited LTA-induced nitric oxide (NO) secretion and inducible nitric oxide synthase (iNOS) expression in BV-2 microglial cells, without affecting cell viability. RGE also inhibited nuclear translocation of nuclear factor kappa B ($NF-{\kappa}B$) p65 and degradation of $I{\kappa}B-{\alpha}$. In addition, RGE increased the expression of heme oxygenase-1 (HO-1) in a dose-dependent manner, and the inhibitory effect of RGE on iNOS expression was abrogated by small interfering RNA-mediated knockdown of HO-1. Moreover, RGE induced nuclear translocation of nuclear factor E2-related factor 2 (Nrf2), a transcription factor that regulates HO-1 expression. Furthermore, the phosphoinositide-3-kinase (PI-3K) inhibitor and mitogen-activated protein kinase (MAPK) inhibitors suppressed RGE-mediated expression of HO-1, and RGE enhanced the phosphorylation of Akt, extracellular signal-regulated kinases (ERKs), p38, and c-JUN N-terminal kinases (JNKs). These results suggested that RGE suppressed the production of NO, a proinflammatory mediator, by inducing HO-1 expression via PI-3K/Akt- and MAPK-dependent signaling in LTA-stimulated microglia. The findings indicate that RGE could be used for the treatment of neuroinflammation induced by grampositive bacteria and that it may have therapeutic potential for various neuroinflammation-associated disorders.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.4
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• pp.479-499
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• 2019

State assessment of an operational tunnel is usually done by performing visual inspection and durability tests by following the detailed guideline for safety inspection (SI) and/ or precision inspection for safety and diagnosis (PISD). In this study, 12 NATM tunnels, which have been operational for more than 10 years, were inspected to figure out the cause of longitudinal cracks for the purpose of modifying the scoring items in the state assessment NATM tunnel related to the longitudinal crack and the thickness of concrete lining. All investigated tunnels were classified into four groups depending on the shape and usage of each tunnel. The causes of longitudinal crack occurrence were analyzed by investigating the correlations between the longitudinal crack and the following four factors: the patterns of ground excavation; construction state of primary support system; characteristics of material properties of the concrete lining; and thickness of lining which was obtained by Ground Penetration Radar (GPR) tests. It was found that influencing factors causing longitudinal cracks in the lining were closely related with the construction condition of the primary support system, i.e. shotcrete, rockbolt, and steel-rib; crack occurrences were not much affected by the excavation patterns. As for the properties of concrete lining materials, occurrence of the longitudinal crack was mostly affected by the following three items: w/c ratio; contents of cement; and strength of lining. When estimating the lining thickness of the concrete lining by GPR tests and taking thickness effect into account in the statement assessment, it was concluded that increase of the index score by an average of 0.03 (ranging from 0.01 up to 0.071) is needed; a more realistic way of state assessment should be proposed in which the increased index score caused by lack of lining thickness should be taken into account.

• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.142-148
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• 2011

This study was carried out to clarify the change characteristics of stream water quality by type of forest from June to August, 2009 in three stands (Castanea crenata, Pinus densiflora and Plantation Land) of Samgye-ri Naedong-myeon Jinju-si Gyeongsangnam-do. The pH of stream water in three stands was highest in Pinus densiflora (pH 7.18) followed by Castanea crenata (pH 6.90) and Plantation land (pH 6.90) while the electrical conductivity of stream water was highest in Plantation land followed by Castanea crenata stand and Pinus densiflora stand was the lowest. Cations contents of stream water in three stands were high in order of $Ca^{2+}$, $Na^{+}$, $Mg^{2+}$, $K^{+}$, and $NH_{4}{^{+}}$. But anions of stream water in Castanea crenata stand and Pinus densiflora stand were high in order of $SO_{4}{^{2-}}$, $Cl^{-}$ and $NO_{3}{^{-}}$ while those of stream water in Plantation land were high in order of $SO_{4}{^{2-}}$, $NO_{3}{^{-}}$ and $C\lambda^{-}$. The stream water in three stands was significant at pH, EC, $NO{^{3-}}$, $Ca^{2+}$, $Mg^{2+}$, $Na^{+}$, $Cl^{-}$, TNU and Color by duncan test. These results indicate that quality of stream water have a difference among three stands. The level of pH, $NH_{4}{^{+}}$, $Cl^{-}$, $SO_{4}{^{2-}}$ and $NO_{3}{^{-}}$ of stream water in three stands were within the domestic use standard for drinking water. but turbidity and color of stream water were more than that of domestic use standard for drinking water. Therefore, non-point sources like urban forest watersheds which are soil erosion and fertilizer application lands should be taken to the appropriate mitigation measures if they are to be used as source of drinking water.

• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.535-543
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• 2022

A CPFD (Computational particle fluid dynamics) model of solar fluidized bed receiver of silicon carbide (SiC: average d_p=123 ㎛) particles was established, and the model was verified by comparing the simulation and experimental results to analyze the effect of particle behavior on the performance of the receiver. The relationship between the heat-absorbing performance and the particles behavior in the receiver was analyzed by simulating their behavior near bed surface, which is difficult to access experimentally. The CPFD simulation results showed good agreement with the experimental values on the solids holdup and its standard deviation under experimental condition in bed and freeboard regions. The local solid holdups near the bed surface, where particles primarily absorb solar heat energy and transfer it to the inside of the bed, showed a non-uniform distribution with a relatively low value at the center related with the bubble behavior in the bed. The local solid holdup increased the axial and radial non-uniformity in the freeboard region with the gas velocity, which explains well that the increase in the RSD (Relative standard deviation) of pressure drop across the freeboard region is responsible for the loss of solar energy reflected by the entrained particles in the particle receiver. The simulation results of local gas and particle velocities with gas velocity confirmed that the local particle behavior in the fluidized bed are closely related to the bubble behavior characterized by the properties of the Geldart B particles. The temperature difference of the fluidizing gas passing through the receiver per irradiance (∆T/I_DNI) was highly correlated with the RSD of the pressure drop across the bed surface and the freeboard regions. The CPFD simulation results can be used to improve the performance of the particle receiver through local particle behavior analysis.

• Journal of Korean Academy of Dental Administration
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• v.5 no.1
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• pp.22-30
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• 2017

Objective: The purpose is to study the factors to impact on the satisfaction of field practice among dental hygiene students and to provide the basic data for the quality improvement of the field practices for dental hygiene students. Methods: A self-reported questionnaires were filled out by 108 dental hygiene students in C city. Questionnaires were composed with the general characteristics, satisfaction to major, and satisfaction to field clinical practice. The data was analyzed by chi-square statistics using SPSS 20.0 program. Results: The higher satisfaction to communication with professor or seniors in department was associated with the higher satisfaction to field clinical practice (p<0.05). The higher satisfaction to field clinical practice hours per week was associated with the higher satisfaction to field clinical practice (p<0.05). The higher interest to major subjects and the satisfaction to the laboratory environment were associated with the higher satisfaction to field clinical practice (p<0.05). Conclusions: The higher satisfaction to major was associated with the higher satisfaction to field clinical practice. Therefore, the systematic curriculum development is needed to improve the satisfaction with major and clinical practice.

• Korean Association for Visual Culture
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• v.23
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• pp.463-524
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• 2013

En exprimant 'la découverte de l'homme', Valéry, dans la Philosophie de la danse, représente «un plaisir qui allait jusqu'à une sorte d'ivresse, et si intense parfois, qu'un épuisement total de ses forces, une sorte d'extase d'épuisement pouvait seule interrompre son délire, sa dépense motrice exaspérée». Dans le même sens du plaisir, Jayadéva, dans son dithyrambe du Gîta-Govinda, représente la danse de Harî, une des nombreuses formes de Vichnou. Excités par le brûlant désir des jeux de la volupté, Hari et son amante Râdhâ cherchent au cours de la danse Râsa l'énergie vitale. Voilà la source du plaisir mystérieux valéryen. Ensuite l'eau, «élément essentiel de toute vie», est la mesure du temps de même que le soleil, l'eau est le principe de l'harmonie comme celui du monde. Finalement, chez Valéry, sous les diverses infleunces de l'eau mythique, la mer devient l'Océan de lait, soit le lieu de naissance, soit la substance maternelle, soit l'essence da la création universelle. Or tout au long de 「La Dormeuse」, Valéry évoque l'image de 'Vichnou-Narayana' sous l'influence de la mythologie indienne. Et sous une autre influence de Flaubert, Valéry évoque « d'étranges mondes abstraits». Malgré tout, Valéry crée lui-même, dans 「La Dormeuse」, une nouvelle image d'un monde abstrait : 'Vichnou-Narayana' couché sur un lit de lotus, porté par les replis du grand serpent Ananta, qui élève au-dessus du dieu endormi méditant, ses sept têtes formant une éspèce de dais - du sein de Narayana, richement décoré d'un collier d'étoiles et d'une couronne de pierres précieuses en forme de disque, croit un lotus qui porte Brahma dans son calice ; Lakchmi est aux pieds de son divin époux. L'épisode des dieux indiens est à un stade encore plus avancé de la destruction du symbole. Ils sont réduits à des formes symboliques obscures, non commentées et même difficilement identifiables. Le dieu rose qui mord son orteil dans une attitude à la fois mystérieuse et grotesque, c'est Vichnou qui a, selon le vichnouisme, le premier rôle dans la création du monde. Il flottait avant la création sur les eaux, couché sur une feuille de figuier, sous la forme d'un jeune enfant qui porte son pied vers sa bouche. Cette scène évoque la méditation et le repli sur soi de la divinité avant le commencement. Valéry désigne la cosmogonie particulière d'une religion bien déterminée(le vichnouisme) sans la nommer et en la vidant de son sens pouratnt capital, laissant subsister un symbole guetté par le grotesque, un dieu en enfance ; d'autre part, cette cosmogonie est télescopée et intégrée par une cosmogonie d'origine différente : le désemboîtement des trois dieux renvoie à la théorie sivaiste du Lingam, l'arbre de vie. Les dieux de la tirinité iendienne se détachent les un après les autres et il ne reste plus que la fleur sous la garde de Vichnou. Le désemboîtement des dieux paraît bien se référer à cette conception, malgré l'absence du lingam. Enfin toute la forme veille ; et tous les yeux sont ouverts.

• Journal of Life Science
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• v.33 no.10
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• pp.783-790
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• 2023

Modern people have an increased incidence of metabolic diseases due to changed eating habits, and diabetes is considered the most significant metabolic disease. Given that existing diabetes treatments are accompanied by side effects, the aim of this study was to identify traditional natural products that have anti-diabetic activity. The potential anti-diabetic and antioxidant activities of natural products were examined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, α-glucosidase assay, and protein tyrosine phosphatase 1B (PTP1B) inhibition assay. Methanol extracts of Ulmus davidiana var. japonica, Acer tegmentosum branches, Nelumbo nucifera seeds, and Carthamus tinctorius seeds were found to have high anti-diabetic activity and further fractionated with solvents using ethyl acetate and butanol. Consequently, the ethyl acetate fraction of C. tinctorius seeds (MG-11-E) with high α-glucosidase and PTP1B inhibitory activity was selected. MG-11-E was subjected to preparative thin layer chromatography, and fraction #6 showed high α-glucosidase and PTP1B inhibitory activity. Fraction #6 was analyzed and fractionated via high performance liquid chromatography with 50% methanol as the mobile phase, and anti-diabetic activity was observed in the sample that eluted after 4 min as a single peak. The α-glucosidase inhibitory activity exhibited by this sample seemed to be greater than the PTP1B inhibitory activity; thus, it was concluded that a greater anti-diabetic therapeutic effect may be achieved by combining this agent with natural products that inhibit PTP1B activity.

• Applied Biological Chemistry
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• v.6
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• pp.61-77
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• 1965

In this experiment, Akiochi was studied especially on plant growth on the degraded soils. Besides, such soils were carefully examined on its character and plant body was analysed to know the difference in various mineral contents. For this purpose, paddy cultivation was done with the variety Pal Dal at Suwon, Sosa and Pyungtak. Three plots were chosen at each location as the normal and 2 levels of akiochi, a-the stronger and b-the weaker. Harvests from these 9 plots were measured agronomically and also chemically analysised. As for soil, after an observation on vertical section of soil, samples from each layer were also studied both physically and chemically. The results are summarized as follows. 1. Outer changes in rice plant and changes in yield components. 1) Rice from Akiochi soil showed remarkably shortened culm length, head length, protrusoion length, blade length of boot leaf, and coleoptile length, compared with that from the normal paddy field. 2) There was a tendency for Akiochi rice to have more heads per plant. 3) Akiochi rice showed poorer intercalary growth of upper 3 internodes. The ratio of this upper internode length to total culm length was also smaller in this case. Consquently the ratio of lower internode length to total culm length became larger than that from normal peddy field. 4) Akiochi rice showed significantly fewer first spikelets and attached grains of head at main stem. 5) Maturing rate of both this main seem of whole plant body was remarkably lower than that of normal rice. 6) Akiochi rice showed lower head weight of main stem, total hulled rice weight, total grain yield, 1000-grain weight, straw weight and straw-hulled rice ratio. 2. Physical and chemical study on soil. 1) Akiochi soil showed thinner upper layer and total thickness of upper and lower parts was smaller than that of normal. 2) Akiochi soil of Suwon was mainly composed of sand, while that of Sosa and Pyungtak was composed of heavy clay. 3) Chemical analysis indicated that content of $SiO_2$ in upper layer is always lower than that of normal. But no other common tendencies were found. 4) This analysis further lillustrates lower content of Fe, & Mn at Suwon ; of Mn at Sosa and higher content of Fe at Sosa and organic matters at Pyungtak. 5) Some differences in the content of N in each plot could be marked though irregular. 3. Chemical Composition of plant body. 1) Chemical analysis on grain, boot leaf and straw did not suggest any remarkable differences between normal and Akiochi rice, except that the latter contains less Si in boot leaf and less Mn in straw. 2) Contents of each chemical element were measured in grain and straw to calculate the percentage of element content in grain to that of whole plant body including both grain and straw. Here, Akiochi rice always showed lower value in N, K and Mn. 4. Relationship between chemical composition of plant body and that of soil. Akiochi soil at Sosa marked lower content of Mn. This caused another lower content of this element in grain, boot leaf and straw. But except that, no remarkable relationship could be found in this study.

• Radiation Oncology Journal
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• v.23 no.3
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• pp.186-193
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• 2005

Purpose: To improve the management of a medical linear accelerator, the records of operational failures of a Varian CL2l00C over a ten year period were retrospectively analyzed. Materials and Methods: The failures were classified according to the involved functional subunits, with each class rated Into one of three levels depending on the operational conditions. The relationships between the failure rate and working ratio and between the failure rate and outside temperature were investigated. In addition, the average life time of the main part and the operating efficiency over the last 4 years were analyzed. Results: Among the recorded failures (total 587 failures), the most frequent failure was observed in the parts related with the collimation system, including the monitor chamber, which accounted for $20\%$ of all failures. With regard to the operational conditions, 2nd level of failures, which temporally interrupted treatments, were the most frequent. Third level of failures, which interrupted treatment for more than several hours, were mostly caused by the accelerating subunit. The number of failures was increased with number of treatments and operating time. The average life-times of the Klystron and Thyratron became shorter as the working ratio increased, and were 42 and $83\%$ of the expected values, respectively. The operating efficiency was maintained at $95\%$ or higher, but this value slightly decreased. There was no significant correlation between the number of failures and the outside temperature. Conclusion: The maintenance of detailed equipment problems and failures records over a long period of time can provide good knowledge of equipment function as well as the capability of predicting future failure. Wore rigorous equipment maintenance Is required for old medical linear accelerators for the advanced avoidance of serious failure and to improve the qualify of patient treatment.