• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.86.1-86.1
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• 2012

The MHD virial theorem applied for observed photospheric field may be the one of way to estimate magnetic energy of generally invisible coronal magnetic structure. However, the photospheric field is not in a force-free state, so the application of virial theory needs some care. Here we use a series of MHD simulations of emerging field to investigate how we can apply the virial theorem to the emerging field. In early emerging phase, virial energy has a minus value although positive area at the photosphere is continuously generated toward a late emerging phase. We discuss why this tendency occurs. Then we derive the critical height where the actual emerging magnetic energy is almost comparable to the virial energy. If the difference between virial energy and magnetic energy becomes 10 percentage of the magnetic energy, we define this is the critical height, and assume the emerging field is close to force-free. We also discuss how the critical height changes with the initial twist of an emerging flux tube.

• Nuclear Engineering and Technology
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• v.38 no.6
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• pp.535-550
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• 2006

The objectives of this paper are twofold to summarize the new findings and confirmed results from the Phebus FPT-1 experimental data and to report useful information to MELCOR users regarding the better use of MELCOR. For the core damage behavior, the early stage of a melt progression was predicted well; however, the late phase models, concerned with fuel dissolution, oxide cladding failure, fuel slumping, rubble debris heat up, effects of burn-up fuel, and so on, still showed limitations in MELCOR. For the fission product behavior, the comparison showed unexpected phenomena, various limitations, unresolved issues, and even absence of models. The issues summarized in this study have revealed the main areas where our endeavors need to be intensified in order to improve our understanding of severe accident phenomena. From the analysis of the Phebus FPT-1 test results, not only new core damage features, such as foaming or core expansion, but also possible new fission product release patterns due to effects from a high burn-up fuel have raised alternative challenging phenomena that should be solved in the next severe accident research phase.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.137-142
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• 1996

The biosynthesis and catabolite repression of cyclodextrin glucanotransferase(CGTase) and cyclodextrinase(CDase) were studied in Bacillus sp. KJI6. In accompanying to the cell growth, CGTase was synthesized during early growth phase (20h culture) and CDase was synthesized during late growth phase (60h culture). Synthesis of CGTase was rather constitutive than that of CDase in the absence or presence of carbon source. Production of CDase was strongly stimulated by amylopectin and $\gamma$-CD medium (about 6 times), but CGTase synthesis was slightly increased (about 1.3 times). Easily metabolizable carbohydrates such as D-glucose, D- fructose and D-mannose completely repressed the expression of CDase, whereas their repressive effect to CGTase synthesis was relatively negligible. By addition of 10 mM cAMP, any significant effect on the synthesis of the two enzymes was not observed. Hardly metabolizable glucose analogues such as 2-deoxy-D-glucose and 3-0-methyl-D-glucopyranose also did not show any repression on the syntheses of CGTase and CDase. This indicates that D-glucose has to be metabolized to exert its repressive effect. With these results, it seems likely that the biosynthesis of CGTase and CDase are regulated by the catabolite repression due to unknown metabolite(s) of EM pathway.

• Journal of Yeungnam Medical Science
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• v.12 no.2
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• pp.386-392
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• 1995

Desmoid tumor is a type of fibromatosis usually arise in deep musculo-aponeurotic structures, primarily of the trunk and extremities. It is characterized by proliferation of fibroblastic tissue and does not metastasize but may be locally aggressive. Eventhough the surgical margin reveals clean, recurrence often occurs. To analyze the extent of the tumor and homodynamic characteristics exactly, we performed IV bolus CT. Desmoid tumors show peripheral rim enhancement on early phase scan and more strong, central enhancement on late phase IV bolus CT, which reflects abundant fibroblastic components of the tumor. We report two cases of pathologically confirmed desmoid tumor performed IV bolus CT.

• Fisheries and Aquatic Sciences
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• v.24 no.1
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• pp.1-9
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• 2021

Human prostate cancer is the second most frequently diagnosed cancer worldwide, and its incidence rate continues to increase. Advanced prostate cancer is more difficult to treat than early forms due to its chemotherapy resistance. There is need for more effective agents that can inhibit the progression of advanced prostate cancer. Demethoxyfumitremorgin C (DMFTC) was isolated from the fermentation extract of the marine fungus Aspergillus fumigatus. Antiproliferative activity of DMFTC against human prostate cancer PC3 cells was examined through cell cycle analysis by flow cytometry, the fluorescent nuclear imaging analysis with propidium iodide (PI), and proteins expression related to cell cycle arrest and apoptosis were investigated via Western blotting. DMFTC inhibited PC3 cells growth through G1 phase cell cycle arrest and apoptosis induction. It activated the tumor suppressor p53 and the Cdk inhibitor p21, which regulate the cell progression into the G1 phase. Additionally, PI-positive late apoptotic non-viable cells were increased and the expression levels of the G1-positive downstream regulators cyclin D, cyclin E, Cdk2, and Cdk4 were decreased by DMFTC treatment. These results suggest that DMFTC induces G1 arrest and apoptosis induction through regulation of p53/p21-dependent cyclin-Cdk complexes, and it may be a useful therapeutic agent for the treatment of human advanced prostate cancer.

• Archives of Pharmacal Research
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• v.28 no.6
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• pp.685-690
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• 2005

We recently reported that the ginseng saponin metabolite, compound K (20-O-$\beta$-D-glucopyra-nosyl-20(S)-protopanaxadiol, IH901), inhibits the growth of U937 cells through caspase-dependent apoptosis pathway. In this study, we further characterized the effects of compound K on U937 cells and found that, in addition to apoptosis, compound K induced the arrest of the G1 phase. The compound K treated U937 cells showed increased p21 expression; an inhibitory protein of cyclincdk complex. The up-regulation of p21 was followed by the inactivation of cyclin D and the cdk4 protein, which act at the early $G_1$ phase, and cyclin E, which acts at the late $G_1$ phase. Furthermore, compound K induced the activation of JNK and the transcription factor AP-1, which is a downstream target of JNK. These findings suggest that the up-regulation of p21 and activation of JNK in the compound K treated cells contribute to the arrest of the $G_1$ phase.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1396-1408
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• 2020

Filtered containment venting system (FCVS) is one of the severe accident mitigation systems designed to release containment pressurization to maintain its integrity. The thermal-hydraulic behaviors in FCVSs are important since they affect the operation characteristics of the FCVS. In this study, a representative FCVS was modeled by RELAP5/Mod3.3 code, and the Station BlackOut (SBO) was chosen as an accident scenario. The thermal-hydraulic behaviors of an FCVS during long-term operation with two venting strategies (open-and-close strategy, open-and-non-close strategy) and the sensitivity analysis of important parameters were investigated. The results show that the FCVS can operate up to 250 h with a periodic open-and-close strategy during an SBO. Under the combined effects of steam condensation and water evaporation, the solution inventory in the FCVS increases during the venting phase and decreases during the intermission phase, showing a periodic pattern. Under this condition, the appropriate initial water level is 3-4 m; however, it should be adjusted according to the environment temperature. The FCVS can accommodate a decay heat power of 150-260 kW and may need to feed water for a higher decay heat power or drain water for a lower decay heat power during the late phase. The FCVS can function within an opening pressure range from 450 kPa to 500 kPa and a closing pressure range between 250 kPa and 350 kPa. When the open-and-non-close strategy is adopted, the solution inventory increases quickly in the early venting phase due to steam condensation and then decreases gradually due to the evaporation of water; drying-up may occur in the late venting phase. Decreasing the venting pipe diameter and increasing the initial water level can mitigate the evaporation of the scrubbing solution. These results are expected to provide useful references for the design and engineering application of FCVSs.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.268-279
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• 2021

Citrus scab, caused by the fungal pathogen Elsinoë fawcettii, is one of the most important fungal diseases affecting Citrus spp. Citrus scab affects young tissues, including the leaves, twigs, and fruits, and produces severe fruit blemishes that reduce the market value of fresh fruits. To study the molecular responses of satsuma mandarin (C. unshiu) to E. fawcettii, plant hormone-related gene expression was analyzed in response to host-compatible (SM16-1) and host-incompatible (DAR70024) isolates. In the early phase of infection by E. fawcettii, jasmonic acid- and salicylic acid-related gene expression was induced in response to infection with the compatible isolate. However, as symptoms advanced during the late phase of the infection, the jasmonic acid- and salicylic acid-related gene expression was downregulated. The gene expression patterns were compared between compatible and incompatible interactions. As scabs were accompanied by altered tissue growth surrounding the infection site, we conducted gibberellic acid- and abscisic acid-related gene expression analysis and assessed the content of these acids during scab symptom development. Our results showed that gibberellic and abscisic acid-related gene expression and hormonal changes were reduced and induced in response to the infection, respectively. Accordingly, we propose that jasmonic and salicylic acids play a role in the early response to citrus scab, whereas gibberellic and abscisic acids participate in symptom development.

• Physical Therapy Korea
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• v.11 no.4
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• pp.31-41
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• 2004

The purpose of this study was to examine the effect of the angle of a wedged insole on knee varus torque during walking. Fifteen healthy subjects were recruited. Knee varus torque was measured using three-dimensional motion analysis (Elite). Knee varus torque was normalized to gait cycle (0%: initial contact; 100%: ipsilateral initial contact) and stance phase (0%: initial contact; 100%: ipsilateral toe off). The average peaks of knee varus torque during the stance phase of the gait cycle according to the different insole angles (10 or 15 degrees) were compared using one-way ANOVA with repeated measures. The results showed that in the early stance phase, the average peak knee varus torque increased significantly for both the medial 10 and 15 degree wedged insole conditions and decreased significantly for both the lateral 10 and 15 degree wedged insole conditions as compared with no insole (p<.05). However, there were no significant differences between the 10 and 15 degree wedged insole conditions with either the medial or lateral wedged insole (p>.05). In the late stance phase, the average peak knee varus torque increased significantly for the medial 10 and 15 degree wedged insole conditions (p<.05), but not for the lateral 10 and 15 degree wedged insole conditions as compared with no insole (p>.05). We suggest that these results may be beneficial for manufacturing foot orthotic devices, such as wedged insoles, to control medial and lateral compartment forces in the knee varus-valgus deformity. Further studies of the effects of wedged insole angle on knee varus torque in patients with medial-lateral knee osteoarthritis are needed.

• The Korean Journal of Zoology
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• v.38 no.3
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• pp.395-404
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• 1995

In order to study the process of spermiogenesis of the korean striped field mouse Apodemus agrorfus coreae, the cell differentiation of seminiferous epithelium and morphological features of mature sperm in cauda epididymis was examined and the results are as follows: Spermiogenesis was divided, according to the features of cell structure; Golgi, cap, acrosome and spermiation phases were further subdivided into two steps of early and late phases respectively, and maturation phase has only one step. Hence, the spermiogenesis consists of nine phases. in the changes of the chromatin in nucleus, the chromatin granules began to be condensed in the cap phase and the condensation proceeded to form a globular of nucleus at the acrsome phase. Finally, the chromatin regularization was completed and perfect nucleus of sperm was formed at the maturation phase. Sperm head had the falciform, and the outer dence fibers of middle piece were arranged in a horseshoe fashion. The outer dence fiber number 1, 5, 6 and 9 was larger than other fiber number 2, 3, 4, 7, 8.