• Journal of Astronomy and Space Sciences
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• v.39 no.2
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• pp.67-77
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• 2022

The elements that impact the dynamics and collaborations of waves and particles in the magnetosphere of planets have been considered here. Saturn's internal magnetosphere is determined by substantiated instabilities and discovered to be an exceptional zone of wave activity. Interchanged instability is found to be one of the responsible events in view of temperature anisotropy and energization processes of magnetospheric species. The generated active ions alongside electrons that constitute the populations of highly magnetized planets like Saturn's ring electron current are taken into consideration in the current framework. The previous and similar method of characteristics and the perturbed distribution function have been used to derive dispersion relation. In incorporating this investigation, the characteristics of electromagnetic ion cyclotron wave (EMIC) waves are determined by the composition of ions in plasmas through which the waves propagate. The effect of ring distribution illustrates non-monotonous description on growth rate (GR) depending upon plasma parameters picked out. Observations made by Cassini found appropriate for modern study, have been applied to the Kronian magnetosphere. Using Maxwellian ring distribution function of ions and detailed mathematical formulation, an expression for dispersion relation as well as GR and real frequency (RF) are evaluated. Analysis of plasma parameters shows that, proliferating EMIC waves are not developed much when propagation is parallelly aligned with magnetosphere as compared to waves propagating in oblique direction. GR for the oblique case, is influenced by temperature anisotropy as well as by alternating current (AC) frequency, whereas it is much affected only by AC frequency for parallel propagating waves.

• Korean Journal of Environment and Ecology
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• v.16 no.1
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• pp.1-9
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• 2002

This study was carried out to examine the tree-ring growth characteristics of Pinus thunbergii Parl. after replanting on the reclaimed land from the sea in Kwangyang bay, The factors, mostly affecting the growths of Pinus thunbergii Parl. , were the replanting stress and drought. The growth reduction due to replanting occurred in the replanting year and following year, but that due to drought after 2-3 years of replanting. The growth recovery after replanting differed with soil condition. The sites showing fast recovery were the covered ground of improve soil, the ground of medium mounding, the top and the slope ground of big mounding sites. The filled ground of improve soil and the lower ground of big mounding sites showed retarded growths. The mean sensitivity(year-to-year variation) and the coefficient of variation(tree-to-tree variation in a certain year) in tree rings of Pinus thunbergii Parl. were higher in the poor soil sites than in the favourable soil ones. The physical characteristics of the soil, especially soil hardness, were the most crucial. The mean sensitivity and the coefficient of variation were also low in the salty soil environment.

• Journal of Climate Change Research
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• v.7 no.4
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• pp.465-476
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• 2016

This study was conducted to elucidate the ecological characteristics of sub-alpine coniferous forest on Banyabong, Mt. Jiri. Soil pH was 4.20. The contents of organic matter, total N, available P and CEC were 14.15%, 0.43%, 10.1 ppm and $17.17cmol^+/kg$, respectively. Sub-alpine coniferous forest had a relatively soil moisture content with 22.9%. According to the results of importance value analysis, Picea jezoensis (42.7) and Abies koreana (34.0) for tree layer, Rhododendron schlippenbachii (25.5) for subtree layer and Tripterygium regelii (18.4) and Rhododendron mucronulatum (16.6) for shrub layer were high, respectively. Shannon's diversity ranged from 0.3560 to 1.050. Evenness and dominance ranged from 0.398 to 0.733 and 0.267 to 0.601, respectively. A. koreana population had a reverse J-shaped DBH distribution, while P. jezoensis population had a normal DBH distribution. Height growth according to DBH of A. koreana was higher than that of P. jezoensis, which indicate than A. koreana have more effective water use efficiency than P. jezoensis. Annual mean tree ring growth of P. jezoensis and A. koreana showed up 1.792, 1.652, 1.389 mm/yr and 2.081, 1.921, 1.576 mm/yr for small, middle and large diameter tree, respectively.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1898-1906
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• 2004

Nonclassical quinazolinone analogs I, II, and III, in which the glutamic acid moiety of the classical antifolates is substituted by phenylglycine, phenylalanine or aminobenzoic acid and their methyl esters, were synthesized and evaluated as lipophilic inhibitors of thymidylate synthase (TS). The target compounds were generally potent inhibitors of L. casei and human TS with $IC_{50}$ values within the narrow range of 0.2-10 ${\mu}$M and 0.003-0.03 ${\mu}$M, respectively. Further, most of the target compounds showed cytotoxicity against tumor cell lines of murine and human origin with $IC_{50}$ values of as low as 0.050 ${\mu}$M. Substitution of another hydroxyl or carboxylic acid/ester group at the phenyl ring further increased the potency of TS inhibition and cell growth inhibition. Most effective were compounds If and Ic in which extra carboxylic acid/ester was present at the phenyl ring with nanomolar $IC_{50}$ values of 0.0044 and 0.0093 ${\mu}$M against human TS and submicromolar cytotoxic growth inhibition against all four tumor cell lines.

• Journal of Integrative Natural Science
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• v.10 no.3
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• pp.141-147
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• 2017

Vascular endothelial growth factor (VEGF) is an important signaling protein involved in angiogenesis, which is the formation of new blood vessels from pre-existing vessels. Consequently, blocking of the vascular endothelial growth factor receptor (VEGFR-2) by small molecule inhibitors leads to the inhibition of cancer induced angiogenesis. In this study, we performed a two dimensional quantitative structure activity relationship (2D-QSAR) study of 38 N-Phenyl-N'-{4-(4-quinolyloxy) phenyl} urea derivatives as VEGFR-2 inhibitors based on hologram quantitative structure-activity (HQSAR). The model developed showed reasonable $q^2=0.521$ and $r^2=0.932$ values indicating good predictive ability and reliability. The atomic contribution map analysis of most active compound (compound 7) indicates that hydrogen and oxygen atoms in the side chain of ring A and oxygen atom in side chain of ring C contributes positively to the activity of the compounds. The HQSAR model developed and the atomic contribution map can serve as a guideline in designing new compounds for VEGFR-2 inhibition.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.82-85
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• 2007

The Chinese medicinal plant Artemisia annua is the source of the antimalarial compound artemisinin. By the way, Artemisin annula was known have endoperoxide ring structure is included and has anti-malarial effect. Malaria and Toxoplasma gondii (T. gondii) is belong to Apicomplexa genera. So, confirmed whether we go compound 1,5-bis(4-methoxyphenyl)-6,7-dioxa-bicyclo[3.2.2]nonane that have endoperoxide ring structure and there is anti-toxoplasmosis effect. The efficacy of 1,5-bis(4-methoxyphenyl)-6,7-dioxa-bicyclo[3.2.2] nonane alone was examined in vitro and in a murine model of acute toxoplasmosis. In vitro studies were peformed with HeLa cell cultures, with quantification of Toxoplasma growth by a cell proliferation assay. Selectivity of 1,5-bis(4-methoxyphenyl)-6,7-dioxa-bicyclo[3.2.2]nonane was 4.9 in vitro cell proliferation assay, this is higher than sulfadiazine (selectivity was 1.63). For in vivo studies, mice were acutely infected intraperitoneally with 10$^5$ tachyzoites of the virulent RH strain and then treated perorally for 4 days from 6 hours postinfection. Efficacy was assessed by sequential determination of parasite burdens in peritoneal cavity. in vitro, 1,5-bis(4-methoxyphenyl)-6,7-dioxa-bicyclo[3.2.2]nonane inhibited Toxoplasma growth at a concentration of 150mg/kg of body weight per day, the inhibition ratio was estimated to be 85.72%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.5
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• pp.1201-1210
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• 2007

The urban streets as a featured and well performing public space for people should be organized in a way that can work as a whole system through network as well as that can provide amenities fur pedestrian. This is a study on Seattle's 'Blue Ring' project for an analysis focused on how its street weaving system organized and what are the design characteristics of the streets. The results are as followings. (1)Pedestrian oriented design, (2)Urban street as a part of open space that can accommodate human activities, (3)Integrated, not isolated with outer/ other open space, (4)Organically networked in a hierarchical manner that can promote pedestrian movement, (5)Utilization of regionally identical design elements. And Smart Growth concept lies in the core of 'Blue Ring' project.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.78-78
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• 2012

In this presentation I will review the expanding thermal plasma chemical vapour deposition (ETP-CVD) technology, a deposition technology capable of reaching ultrahigh deposition rates. High rate deposition of a-Si:H, ${\mu}c$-Si:H, a-SiNx:H and silicon nanocrystals will be discussed and their various applications, mainly for photovoltaic applications demonstrated. An important aspect over the years has been the fundamental investigation of the growth mechanism of these films. The various in situ (plasma) and thin film diagnostics, such as Langmuir probes, retarding field analyzer, (appearance potential) mass spectrometry and cavity ring absorption spectroscopy, spectroscopic ellipsometry to name a few, which were successfully applied to measure radical and ion density, their temperature and kinetic energy and their reactivity with the growth surface. The insights gained in the growth mechanism provided routes to novel applications of the ETP-CVD technology, such as the ultrahigh high growth rate of silicon nanorystals and surface passivation of c-Si surfaces.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.1
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• pp.66-73
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• 1991

During the growth of macroscopically dislocation-free Czochralski silicon crystal, micro precipitates causing stacking faults in the silicon wafer during the oxidation are formed Thermal history the cryscausing acquire during the growth process is known to be a key factor determining the nucleation of this micro precipitates. In this article, various mechanisms suggested on the formation of microdefects in the silicon crystal are reviewed to secure the nucleation mechanism of the micro precipitates causing OSF whose pattern is normally ring or annular in CZ silicon crytal. B-defects which are known as vacancy clustering are considered to be the heterogeneous nucleation sites for the micro precipitates causing OSF in the CZ silicon crystals.

• Korean Journal of Ichthyology
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• v.25 no.1
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• pp.25-32
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• 2013

We studied the age and growth of striped beakperch (Oplegnathus fasciatus) in the Jeju marine ranching area using a total of 423 otoliths from August 2009 to August 2010. The surface reading method, which was etched with 5% HCl, was the best method to read ages of this fish. The monthly mean fork length ranged from 20.9 cm to 27.7 cm in the Jeju marine ranching area during from August 2009 to August 2010. The annual ring was formed in July to September once a year. Fish were principally composed of 3 to 5 years old and the oldest was 12 years old. The von Bertalanffy growth parameters of this species, which were estimated from a non-linear regression, were $L_{\infty}$=48.20 cm, $t_0$=-1.031yr, and K=0.123/yr.