• 한국세라믹학회지
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• 제36권5호
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• pp.478-482
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• 1999

SrTiO3 :Al, Pr phosphor as an oxide compound phosphor is expect to be applied for a field emission display(FED). In this phosphor the excitation spectrum shows a different tendency according to an addition Al3+ and Pr3+ In this excitation spectrum the main peak at 359 nm represent excitation level of Pr3+(1S0longrightarrow1D2 transition) and the absorption characteristic according to Ti/Sr molar ratio is influenced by the structure symmetry. The emission spectrum exhibits the red luminescence with the radiative decay of the 1D2 states(1D2 longrightarrow3H4 transition) The concentration quenching phenomena at 1D2 state shows up as Al3+ and Pr3+ ion concentration increases.

• Journal of Oral Medicine and Pain
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• 제34권2호
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• pp.153-167
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• 2009

본 연구는 편백 피톤치드에 의해 사멸되지 않는 구강상주균을 분리하고, 이 분리된 세균이 구강 병인균에 대하여 어떠한 영향을 미치는지를 관찰함으로써 편백 피톤치드에 구강 내 세균에 대한 지속적인 이차적 효과를 구명한 실험적 연구이다. 이에 정상인 타액 내의 구강상주균에 1%의 편백 피톤치드를 첨가하여 사멸되지 않고 생존한 200개의 잔존 세균을 뷴리하고 이들이 치주질환과 구취의 중요한 원인균인 Pr. intermedia에 대한 억제효과를 관찰하여 다음과 같은 결론을 얻었다. 1. 선택된 200개의 잔존 세균 중, 148개(74.0%)가 Pr. intermedia를 억제하였다. 2. 선택한 200개의 잔존 세균은 Streptococcus salivarius가 109개(54.5%)로 가장 많이 나타났고, Streptococcus sanguinis가 25개(12.5%), Streptococcus mitis가 15개(7.5%)로 나타났다. 3. Pr. intermedia를 억제하는 148개의 잔존 세균 중, Streptococcus salivarius가 85.3%(93/109), Streptococcus sanguinis가 64.0%.(16/25), Streptococcus mitis가 54.3%(8/15), Streptococcus parasanguinis가 66.7%(6/9), Streptococcus alactolyticus가 100%(8/8)로 나타났다. 따라서 타액 내에서 편백 피톤치드에 저항하는 구강 상주균은 Streptococcus salivarius, Streptococcus sanguinis, Streptococcus mitis 등으로 나타났으며, 이는 치주질환을 일으키고 구취를 발생시키는 대표적 균주인 Pr. intermedia 에 대하여 세균 억제효과를 가지고 있었다. 따라서 피톤치드는 구강 내 유해균을 억제할 수 있고, 잔존하는 구강 상주균과 함께 구강 내 유해균을 억제함으로써 지속적이고 이차적인 효과를 나타냄으로써 치주질환과 구취발생을 예방할 수 있어, 구강 환경 개선을 위한 임상적 근거가 마련될 수 있을 것으로 생각된다.

• Journal of Preventive Medicine and Public Health
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• 제48권2호
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• pp.74-83
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• 2015

Objectives: To examine the sex-specific factors associated with being unaware of one's hepatitis B virus surface antigen (HBsAg) seropositivity status in a large, HBsAg-positive population of Koreans. Methods: In total, 1197 subjects aged 19 years or older who were HBsAg-positive according to data from the 2007-2012 Korea National Health and Nutrition Examination Survey were included. Subjects were considered unaware of their HBsAg seropositivity status if they answered that they had no knowledge of being previously infected by the hepatitis B virus (HBV) or diagnosed with HBV hepatitis. Multivariate Poisson regression models with robust variance estimate were used to assess the significance of the variables using weighted frequencies. Results: The majority (77.8%) of HbsAg-positive Korean adults (females, 81.9%; males, 74.6%) were unaware of their HBsAg seropositivity status. We found that sex (female: prevalence ratio [PR] 1.19), household income (low: PR, 1.15), marital status (never married: PR, 1.18), self-rated health (moderate: PR, 1.14; good: PR, 1.12), and alcohol use (at least 2-3 times/wk: PR, 1.21) were associated with being unaware. In females, age (50 to 59 years: PR, 1.29; ${\geq}70$ years: PR, 1.30), household income (low: PR, 1.37; middle-low: PR, 1.24), and marital status (never married: PR, 1.33) were associated with being unaware. In males, self-rated health (moderate: PR, 1.14; good: PR, 1.21) and alcohol use (at least 2-3 times/wk: PR, 1.21) were associated with being unaware. Conclusions: Factors related to the socioeconomic status of females and the health-related behaviors of males were found to be associated with being unaware of one's HBsAg seropositivity status.

• Biomolecules & Therapeutics
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• 제29권4호
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• pp.373-383
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• 2021

Atherosclerosis is the deposition of plaque in the main arteries. It is an inflammatory condition involving the accumulation of macrophages and various lipids (low-density lipoprotein [LDL] cholesterol, ceramide, S1P). Moreover, endothelial cells, macrophages, leukocytes, and smooth muscle cells are the major players in the atherogenic process. Sphingolipids are now emerging as important regulators in various pathophysiological processes, including the atherogenic process. Various sphingolipids exist, such as the ceramides, ceramide-1-phosphate, sphingosine, sphinganine, sphingosine-1-phosphate (S1P), sphingomyelin, and hundreds of glycosphingolipids. Among these, ceramides, glycosphingolipids, and S1P play important roles in the atherogenic processes. The atherosclerotic plaque consists of higher amounts of ceramide, glycosphingolipids, and sphingomyelin. The inhibition of the de novo ceramide biosynthesis reduces the development of atherosclerosis. S1P regulates atherogenesis via binding to the S1P receptor (S1PR). Among the five S1PRs (S1PR1-5), S1PR1 and S1PR3 mainly exert anti-atherosclerotic properties. This review mainly focuses on the effects of ceramide and S1P via the S1PR in the development of atherosclerosis. Moreover, it discusses the recent findings and potential therapeutic implications in atherosclerosis.

• 대한원격탐사학회지
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• 제18권6호
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• pp.319-326
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• 2002

TRMM-PR/VIRS와 GMS 자료를 이용하여 강수량을 추정하였다. 강수량 추정의 검증에는 기상청의 AWS 관측자료를 이용하였다. 본 연구의 강수량 추정 절차는 다음과 같다: 1) TRMM-PR 자료와 AWS 자료를 이용하여 Z-R 관계식을 도출한다. 2) Z-R 관계식에 의한 추정치와 VIRS의 TBB 자료를 이용하여 강수량 추정식을 도출한다. 3) 새롭게 도출된 식의 VIRS의 TBB 대신 GMS의 TBB 자료를 대입하여 광역의 강수량을 추정한다. Z-R 관계식은 Z=303R$^{0.72}$로 나타났고 상관계수는 0.57이었다. 새롭게 제시된 강수량 추정식에 의한 결과의 상관계수는 0.67, RMSE는 17mm/hr로 나타났다. 강수량 추정식은 집중호우 때 과소추정하는 경향을 보였다.

• ETRI Journal
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• 제23권3호
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• pp.97-105
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• 2001

$1.6\;{\mu}m$ emission originated from $Pr^{3+}:\;(^3F_3,\;^3F_4)\;{\longrightarrow}\;^3H_4$ transition in $Pr^{3+}-\;and\;Pr^{3+}/Er^{3+}$-doped selenide glasses was investigated under an optical pump of a conventional 1480 nm laser diode. The measured peak wavelength and fullwidth at half-maximum of the fluorescent emission are ~1650nm and 120nm, respectively. A moderate lifetime of the thermally coupled upper manifolds of ${\sim}212{\pm}10{\mu}s$ together with a high stimulated emission cross-section of ${\sim}(3{\pm}1){\times}10^{-20}\;cm^2$ promises to be useful for $1.6{\mu}m$ band fiber-optic amplifiers that can be pumped with an existing high-power 1480 nm laser diode. Codoping $Er^{3+}$ enhances the emission intensity by way of a nonradiative $Er^{3+}:\;^4I_{13/2}\;{\longrightarrow}\;Pr^{3+}:\;(^3F_3,\;^3F_4)$ energy transfer. The Dexter model based on the spectral overlap between donor emission and acceptor absorption describes well the energy transfer from $Er^{3+}$ to $Pr^{3+}$ in these glasses. Also discussed in this paper are major transmission loss mechanisms of a selenide glass optical fiber.

• 한국결정학회지
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• 제11권1호
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• pp.10-15
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• 2000

Compound trans-[FeH(NCS(i-Pr)-S)(dppe)₂](1) reacted with isopropyl iodide (i-PrI) to give an Fe(II)-organic isothiocyanide complex, trans-[FeH(NCS(i-Pr)-S)(dppe)₂]I (2). Compound 2 was structurally characterized, in which the hydride ligand appears to be involved in the "dihydrogen" bonding, M-H…H-C. Crystallographic data for 2: monoclinic space group P2₁/n, a=13.490(2)Å, b=17.269(3)Å, c=21.384(3)Å, β=90.682(7)°, Z=4, R(wR₂)=0.0348(0.0894).

• Journal of Magnetics
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• 제3권3호
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• pp.74-77
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• 1998

A method to analyze the anisotropy constants of a two sublattice system with uniaxial anisotropy has been investigated by extending the Sucksmith and Thompson's method to higher order anisotropy terms. Using the method, a set of anisotropy constants for Pr-sublattice of $Pr_2Fe_{14}B at 4.2K has been obtained as K_{1Pr}=5210 J/kg, K_{2Pr}=-7200 J/kg, K_{3Pr}=-770 J/kg, K_{4Pr}=4940 J/kg and K_{SPr}=700 J/kg for N_{PrFe}=2.2 T/Am^2kg^{-1}.$ The magnetization calculated by an energy minimum method by using the sublattice anisotropy constants well reproduced the experimental results and satisfied the simulation assumptions.

• The Plant Pathology Journal
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• 제21권3호
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• pp.288-292
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• 2005

Pathogenesis-related protein-1a (PR-1a) is strongly induced in tobacco plants by pathogen attack, exogenous salicylic acid (SA) application and by other developmental processes. In order to develop a rapid screening system for the selection of plant defense-inducing compounds originated from various sources, we have transformed tobacco Samsun NN plants with a chimeric construct consisting of GUS $(\beta-glucuronidase)$. In the $T_1$ generation, three transgenic lines having stable GUS expression were selected for further promoter analysis. Using GUS histochemical assay, we observed strong GUS induction driven by PR-1a promoter in PR1a-GUS transgenic tobacco leaves in response to the exogenous application of SA or benzol (1,2,3) thiadiazole-7-carbothioic acid S-methyl ester (BTH), a SA­derivative compound. In addition, GUS expression was maintained locally or systemically in PR1a-GUS transgenic line $\#5\;T_2$ generation) until after 3 days when they were treated with same chemicals. Our results suggested that the PR1a-GUS reporter gene system in tobacco plants may be applicable for the large-scale screening of defense-inducing substances.

• Journal of Acupuncture Research
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• 제22권6호
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• pp.1-15
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• 2005

Objectives : The aim of this study was to investigate the effect of Peucedani Radix herbal acupuncture(PR-HA) at St36(joksamni) on ovalbumin-induced asthma in mice. Methods : C57BL/6 mice were sensitized and challenged with OVA(ovalbumin) for 12 weeks(once a week) C57BL/6 mice were injected, inhaled and sprayed with OVA for 12 weeks (3times a week). One of the two experimental groups was just treated with needle-prick on St36 and the other group was treated with 1% concentrations of PR-HAS at St36, for the later 8 weeks (3times /week). Results : 1. The weight and total cells of lung of the mice group treated with PR-HA decreased significantly compared with those of control group. 2. Total Leukocytes and Eosinophils in BALF of the mice group treated with PR-HA decreased significantly compared with those of control group. 3. Eosinophils in BALF of the mice group treated with PR-HA in Photomicrographs decreased significantly compared with those of control group. 4. According to Histological analysis of lung sections, it decreased significantly adhension of collagen in PR-HA than those of control group 5. The concentration of IgE, IL-4, IL-5, in BALF and IL-4, IL-5, Il-13 in serum of the mice group treated with PR-HA decreased significantly compared with that of control group. 6. The number of Gr-1+/CD11b+, CD11b+, CD3-/CCR3+, CD4+, CD3e+/CD69+ , CD23+B220+ cells in the lungs of the mice group treated with PR-HA decreased significantly compared with those of control group. 7. The cytokine's manifestation of mRNA of the mice group treated with PR-HA with RT-PCR decreased significantly compared with that of control group. Conclusion : We conclude that PR-HA is effective on OVA-induced asthma of C57BL/6 mouse.