• Journal of the Korean Mathematical Society
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• v.50 no.2
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• pp.393-410
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• 2013

Let $R{\subseteq}T$ be an extension of integral domains, X be an indeterminate over T, and R[X] and T[X] be polynomial rings. Then $R{\subseteq}T$ is said to be LCM-stable if $(aR{\cap}bR)T=aT{\cap}bT$ for all $0{\neq}a,b{\in}R$. Let $w_A$ be the so-called $w$-operation on an integral domain A. In this paper, we introduce the notions of $w(e)$- and $w$-LCM-stable extensions: (i) $R{\subseteq}T$ is $w(e)$-LCM-stable if $((aR{\cap}bR)T)_{w_T}=aT{\cap}bT$ for all $0{\neq}a,b{\in}R$ and (ii) $R{\subseteq}T$ is $w$-LCM-stable if $((aR{\cap}bR)T)_{w_R}=(aT{\cap}bT)_{w_R}$ for all $0{\neq}a,b{\in}R$. We prove that LCM-stable extensions are both $w(e)$-LCM-stable and $w$-LCM-stable. We also generalize some results on LCM-stable extensions. Among other things, we show that if R is a Krull domain (resp., $P{\upsilon}MD$), then $R{\subseteq}T$ is $w(e)$-LCM-stable (resp., $w$-LCM-stable) if and only if $R[X]{\subseteq}T[X]$ is $w(e)$-LCM-stable (resp., $w$-LCM-stable).

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.273-276
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• 2009

The development of computer hardware equipments and computer graphics technique has taken lots of changes in a movie production of VFX (visual effects) part. Particularly, through the developing of various computers graphic techniques to create imaginary creatures in a movie as high resolution like a real, weight and percentage of creature's appearance in a film is increasingly higher than past year. Creatures play an important role in a various movies such as monster films 'D War' and 'The Host', as well as fantasy films 'Harry Potter', 'The Chronicles of Narnia' and "The Lord of the Rings". The fact that authorized movie sites and organizations rank monsters in diverse processes is to show it. Nevertheless significance and priority of creatures are increased day by day, there are rare to see a basic research about classification and materiality of creatures. In this study, it is organizing materiality of creatures and designing realistic and convincing creatures to help efficient visualization from now on.

• The Korean Journal of Physiology
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• v.24 no.1
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• pp.115-121
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• 1990

The interaction between a calcium channel blocker nifedipine and atrial natriuretic peptide (ANP) was examined in normotensive and renal hypertensive rats. The infusion of either ANP or nifedipine produced a significant decrease in mean arterial pressure (MAP). The combined infusion of ANP with nifedipine resulted in a greater fall of MAP than did the infusion of each drug alone. ANP significantly increased urinary volume and excretion of sodium, while nifedipine was without effects. The diuretic/natriuretic effects of ANP were potentiated by the combined infusion with nifedipine. The vasodepressor and renal effects of ANP or nifedipine were qualitatively similar between the normotensive and hypertensive rats. Nifedipine caused an upward and leftward shift of the ANP dose-relaxation curve of the phenylephrine-precontracted thoracic aortic rings isolated from the normotensive rats , suggesting that the vasodilation sensitivity to ANP is increased in the presence of nifedipine. These results indicate that nifedipine enhances the vasodepressor effect of ANP, the likely mechanisms being attributable to a contraction of effective intravascular volume as a consequence of potentiated renal excretion and a greater peripheral vasodilation.

• Journal of Ginseng Research
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• v.21 no.2
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• pp.119-124
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• 1997

Chronic hypertension is associated with impaired endothelial function such as reduced synthesis/release of endothelium-derived relaxing factor(EDRF, nitric oxide) and increased synthesis/release of endothelium-derived contracting factor(EDCF) including prostaglandin endoperoxide($PGH_2$) , superoxide anion both in animals and in humans. We have previously shown that ginsenosides lower the blood pressure and enhance the release of nitric oxide(NO) from endothelial cells in the rat aorta of the normotensive rats. The aim of the present study is to examine whether in vivo treatment of spontaneously hypertensive rats(SHRs) with protopanaxatriol ginsenosides(PPT) reduces the blood pressure and improves endothelial function in the isolated thoracic aorta of SHR. In addition, the contractile response to $PGH_2$ and superoxide anion in the aorta treated with PPT was assessed. SHRs at the age of 16 weeks were savaged with PPT(30 mg/kg/ day) for 2 weeks and systolic blood pressure was measured by the tail-cuff method. Whereas blood pressure was significantly increased in SHRs by 5.4 mmHg during this period of treatment, treatment of SHRs with PPT blocked the elevation of blood pressure. Endothelium-dependent relaxation to acetylcholine was significantly increased in the PPT-treated animals. $PGH_2$- and oxygen-derived free radical-induced contractions were significantly suppressed in aortic rings without endothelium from PPT-treated SHR. These findings indicate that PPT reduces the blood pressure of SHR, which may be associated with either increase of NO release or by antagonizing superoxide anion and PGH2 in the aortic smooth muscle.

• The Korean Journal of Mycology
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• v.25 no.4 s.83
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• pp.340-347
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• 1997

Conidia and cultural characteristics of isolates of chromogenic and teleomorphic strains of Colletotrichum gloeosporioides from apple and red pepper were compared. The mycelial growth of teleomorphic strains was faster than that of chromogenic strains in potato dextrose agar and V-8 agar. The chromogenic isolates from apple and red pepper developed. white gray to gray green mycelial rings interspersed with salmon to apricot colored conidial masses in colonies on potato dextrose agar and V-8 agar and none formed on ascigerous stage in cultures. The chromogenic isolates from red pepper produced conidia, most with one apex attenuated on apple and potato dextrose agar whereas fusiform and smaller conidia were produced in V-8 agar and water agar leaf medium. The chromogenic isolates from apple produced fusiform conidia in the media tested. The teleomorphic isolates from apple and red pepper produced cylindrical conidia, most with both apices rounded, developed white gray to dark olive green in a zonate pattern with small dark spots throughout colonies and formed the ascigerous stage in cultures.

• Korean Journal of Veterinary Research
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• v.49 no.4
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• pp.345-349
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• 2009

Polychlorinated biphenyls (PCBs) are synthetic organic compounds with two benzene rings and well known environmental pollutants. This study examined the effect of persistent exposure to 2,$3^{\prime}$,4,$4^{\prime}$,5-pentachlorobiphenyl (PCB118) on the proinflammatory and proapoptotic factors in male rats. Male Sprague Dawley rats were administered weekly intraperitoneal injections of either PCB118 (20 mg/kg) dissolved in corn oil or corn oil alone. One week after 2 and 5 administrations, the rats were sacrificed by a pentobarbital injection. The effect of PCB118 on the expression of cyclooxygenase 2 (COX-2), cytosolic phospholipase A2 (cPLA2), peroxisome proliferator-activated receptor gamma, Bcl and Bcl-2-associated X protein (BAX) was investigated. The level of COX-2 and cPLA2 expression was higher in the PCB118-treated rats than the control. These results suggest that PCB118 has a proinflammatory effect in rats.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.1-10
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• 2005

Tree-ring chronologies can be used to date historical buildings or furnitures by matching them with chronologies of living trees. Tree-ring dating gives a calendar year to each tree ring and produces the cutting dates of logs or woods. In this study, we intend to extend our tree-ring dating applications to Korean furnitures. As a case study, we examined two traditional furnitures, one cabinet 'Jang' and the other chest, 'Bandaji'. The cutting date of the cabinet woods was A.D. 1839. The date of the outmost ring in the chest was A.D. 1904. Due to no bark present, the cutting date of the chest was only estimated as $1930{\pm}10$ by 'sapwood rings' estimation method. Ring-width pattern of the latter one also indicated that the origin of the chest must be Kangwon province. This case study suggests that tree-ring dating would be a useful and accurate method to identify the critical dates for the chronicles of Korean traditional furnitures.

• Journal of the Korean Wood Science and Technology
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• v.44 no.2
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• pp.157-165
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• 2016

This study investigated several anatomical characteristics of Paulownia tomentosa roots. The root wood was separated into three parts from stem base (top, middle, and base) at different positions below ground. Qualitative anatomical data suggested that the growth rings in earlywood and latewood were structurally different. Furthermore, the root wood vessels were found having 2 to 3 radial multiples and they were appeared in the form of clusters. In addition, some sheath cells and septate axial parenchyma were observed. Regarding the quantitative anatomical characteristics, vessel and ray numbers per $mm^2$, as well as ray width and height differed significantly among the top, middle, and base rood wood parts. However, there were no significant differences in vessel diameters, cell wall thickness, and width and length of wood fibers among those parts. The crystallinity of the root top part was slightly higher than that of the middle and base parts. Furthermore, the vessel numbers, ray numbers, and ray width and height in the near pith (NP) area were higher compared to those in the near bark (NB) area. However, the fiber width and fiber length at NP were lower than those at NB. Overall, this study demonstrated some significant differences in the anatomical characteristics of the top, middle, and base parts of root wood from Paulownia tomentosa.

• Journal of the Korean Vacuum Society
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• v.20 no.4
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• pp.252-257
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• 2011

The ring formation and electronic properties of furan adsorbed on graphene layers grown on 6H-SiC (0001) has been investigated using atomic force microscopy (AFM), near edge X-ray absorption fine structure (NEXAFS) spectra for the C K-edge, and core level photoemission spectroscopy (CLPES). Moreover, we observed that furan molecules adsorbed on graphene could be used for chemical functionalization via the lone pair electrons of the oxygen group, allowing chemical doping. We also found that furan spontaneously form rings with one of three different bonding configurations and the electronic properties of the ring formed by furan on graphene can be described using by AFM, NEXAFS and CLPES, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.1
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• pp.44-50
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• 2004

Age and growth of the blue spot mudskipper (Boleophthalmus pectinirostris) were studied using the samples caught in the mud flats of southwestern Korea during April-October, 2001. The value of the marginal index of the second actinost bone was the lowest in July and October and indicated by rings that was analysis of formed teice a year. The relationship between body weigt (BW) and total length (TL) was expressed as BW=0.000005 $TL^{3.12}\;(r^2=0.92)$ for females and BW=0.000476 $TL=^{2.18}\;(r^2=0.62)$ for males. Regression analysis of TL-BW between sexes showed a significant difference (P<0.01). Relationship between total length (TL) and actinost radius (R) were expressed as TL=16.9+33.4 R $(r^2=0.62)$ for females and TL=45.8+26.2 R $(r^2=0.41)$ for males. Growth parameters, $L\infty,t_0$ and K were estimated as 165.2 mm, -0.23, and 1.07 for females and 155.3 mm, -0.35, and 1.39 for males.