• 한국전기전자재료학회논문지
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• 제25권8호
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• pp.646-650
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• 2012

Multifunctional structures with two kinds of materials have been intensively investigated in order to improve their electrical characteristic with two functions simultaneously. However, the research regarding of multifunctional ceramic sensor is still in a preliminary stage and how to integrate them with low-cost and high-yield mass production process remains a challenge issue. In this study, we fabricated the multifunctional ceramic sensor composed of temperature and gas sensors. Moreover, we investigated the CO sensing properties of three dimensional nanostuctured $Nb_2O_5$ thin film gas sensors fabricated with silica ($SiO_2$ nanosphere (${\O}$= 750 nm). Compared to plain films, the nanostructured films show enhanced gas sensing of greater sensitivity and a faster response. This result reveals that significantly increased sensitivity is an increase in the effective surface area for the adsorption of gas molecules.

• Natural Product Sciences
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• 제26권3호
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• pp.207-213
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• 2020

Characterization and in vitro inhibition studies of protease inhibitor from the mushroom Pleurotus floridanus (PfTI) towards the pest Papilio demoleus is studied. The addition of 1 mM Mn²⁺, Na²⁺, Ba²⁺ and Ni ²⁺ enhanced the PfTI activity. The ICP-atomic emission spectrum showed the presence of Ca²⁺, Mg²⁺ and Zn²⁺ in the PfTI. Surfactants SDS and CTAB at a concentration of 1% reduced the PfTI activity whereas, the nonionic detergents Triton X and Tween 80 increased the activity. The inhibitory activity gradually decreased with increase in concentration of DMSO and H₂O₂. The activity was increased by dithiothreitol up to a concentration of 80 μM and inactivated at 140 μM. The activity of PMSF modified PfTI was drastically reduced to 0.234 U/mL at 4 mM concentration and similar results were obtained for modification of cysteine by N-Ethylmaleimide at slightly higher concentrations. The complex of trypsin and PfTI showed complete loss in fluorescence intensity at 343 nm compared with control. In vitro inhibition studies of PfTI with midgut proteases isolated from citrus pest P. demoleus with protease activity of 1.236 U was decreased to 0.613 U by 50 μL (0.1 mg/mL) of the inhibitor. Inhibitor was stable up to 0.04 M concentration of HCl.

• 한국환경보건학회지
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• 제33권6호
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• pp.479-487
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• 2007

[ $PM_{2.5}$ ], particulate matter less than 2.5 um in a diameter, can penetrate deeply into the lungs. Exposure to $PM_{2.5}$ has been associated with increased hospital visits for respiratory aliments as well as increase mortality. $PM_{2.5}$ is a byproduct of combustion processes and as such has a complex composition including a variety of metallic elements, inorganic and organic compounds as well as biogenic materials (microorganisms, proteins, etc). In this study, the average concentrations of fine particulates $PM_{2.5}$ have been measured simultaneously in Asan and Seoul, Korea, by using particulate matter portable sampler from September 2001 to August 2002. Sample collection filters were analyzed by ICP-OES to determine the concentrations of metallic elements (As, Ni, Fe, Cr, Cd, Cu, Pb, Zn, Si). Annual mean $PM_{2.5}$ concentrations in Asan and Seoul were 37.70 and $45.83\;{\mu}g/m^3$, respectively. The highest concentrations of $PM_{2.5}$ were found in spring season in both cities and the concentrations of measured metallic elements except As in Asan were higher than those in Seoul, suggesting that yellow dust in spring could affect $PM_{2.5}$ concentrations in Asan rather than Seoul. The correlation coefficients of Pb and Zn were 0.343 for Asan and 0.813 for Seoul during non-yellow dust condition, suggesting that Pb and Zn were influenced with the same sources. The correlation coefficients between Si and Fe in the fine particulate mode were 0.999 (Asan) and 0.998 (Seoul) during yellow dust condition. It was suggested that these two elements were impacted by soil-related transport from China during the yellow dust storm condition.

• BMB Reports
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• 제47권11호
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• pp.631-636
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• 2014

Aurora-A is a centrosome-localized serine/threonine kinase that is overexpressed in multiple human cancers. We previously reported an intramolecular inhibitory regulation of Aurora-A between its N-terminal regulatory domain (Nt, amino acids [aa] 1-128) and the C-terminal catalytic domain (Cd, aa 129-403). Here, we demonstrate that although both Aurora-A mutants (AurA-K250G and AurA-D294G/Y295G) lacked interactions between the Nt and Cd, they also failed to interact with Ajuba, an essential activator of Aurora-A, leading to loss of kinase activity. Additionally, overexpression of either of the mutants resulted in centrosome amplification and mitotic spindle formation defects. Both mutants were also able to cause G2/M arrest and apoptosis. These results indicate that both K250 and D294/Y295 are critical for direct interaction between Aurora-A and Ajuba and the function of the Aurora-A complex in cell cycle progression.

• 대한화학회지
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• 제30권2호
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• pp.216-223
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• 1986

Dansyl 유도화된 아미노산의 광학이성질체를 분리하기 위해 광학활성인 L-arginine과 몇가지 금속(구리, 아연, 카드뮴, 니켈)의 킬레이트를 이동상에 첨가하여 역상 칼럼내에서 분리를 시도했다. 구리 킬레이트 이외의 것은 광학이성질체의 분리가 안되었다. 아미노산의 광학이성질체의 분리 거동은 이동상의 pH 및 유기용매조성, 완충용액의 종류와 농도, 금속의 종류와 킬레이트 농도에 의해 영향을 받음을 알 수 있었다. Valine, metionine, leucine, phenylalanine은 D형이 먼저 용리되고 serine과 alanine은 L형이 먼저 용리되었으며 threonine은 D형과 L형의 분리현상이 나타나지 않았다. 이러한 분리거동은 리간드 교환반응에 의한 (D, L-DNS-AA) (M) (L-Arg) 3종류 착물이 형성될때의 입체 특이성효과로써 설명할 수 있다.

• 한국토양비료학회지
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• 제49권5호
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• pp.524-530
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• 2016

Agricultural soils near or around industrial complexes can contain a certain amount of heavy metals that readily enter the food chain and negatively affect human health. Therefore, we conducted the study to investigate the distribution of selected heavy metals, including arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), mercury (Hg), and zinc (Zn), in farm-land soils around fifteen industrial complexes in the southwestern provinces, Korea. The concentrations of heavy metals in the soil samples were determined by the pseudo-total aqua regia (3 HCl : $1HNO_3$) digestion procedure. The heavy metal concentrations in most soils examined did not exceed the levels of Soil Contamination Warning Standard (SCWS) for agricultural lands (Region 1) presented in Soil Environment Conservation Law (SECL) established by Ministry of Environment (MOE), Korea. However, only one sampling site showed higher As amount ($27.1mg\;kg^{-1}$) than the SCWS level of As ($25mg\;kg^{-1}$). Pollution index (PI) for heavy metals did not exceed 1.0. The PI values were significantly positively correlated (p < 0.01) with the heavy metal concentrations. In particular, the values of correlation coefficient between the Cd and Pb concentrations and the PI values were higher than those estimated from other combinations, and thus the amounts of Cd and Pb in the agricultural soils highly affected the PI values for the heavy metals.

• 자원환경지질
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• 제29권1호
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• pp.87-103
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• 1996

The purposes of this research are to investigate the pollution level of heavy metals due to the urbanization and industrialization in the satellite cities of Seoul, and to assess the chemical species and the sources of heavy metals in highly contaminated soils and dusts. Soil and dust samples were collected from the Uijeongbu and the Koyang cities, which are northern and the northwestern satellite cities of Seoul metropolitan city, respectively. Relatively high pH values($6.3{\sim}9.9$) were found in roadside soils compared with agricultural and forest soils. Difference in pH values of soils was not identified between before and after rainy seasons. In spite of no specific pollution sources in the above cities, the contents of Cu, Pb, and Zn in soils and dusts were much higher than the world average contents. The metal levels in dusts were higher than those in soils, but the metal concentration in dusts was significantly decreased after rainy season. Pollution index was high(> 1.0) in the areas of heavy traffic, industrial complex, and city centres. There is an appreciable proportion of total Zn in exchangeable/water-acid soluble fraction. Copper is predominantly associated with reducible and oxidizable phases, whereas Pb is largely in reducible association. It is concluded that the mobility and bioavailability of metals are high in the order of Zn >> Cu > Pb, on the basis of characteristic particle morphology and chemical composition, Pb-containing particles are originated probably from the automobile exhaust, particularly in heavy traffic areas. The metallic forms and iron-oxide associated forms of Cr, Ni, Cu, Zn, and Pb can be assessed as industrial origin.

• Journal of Genetic Medicine
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• 제7권1호
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• pp.9-15
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• 2010

선천성 갑상샘 기능 저하증은 신생아 3,000명 내지 4,000명당 한 명꼴로 발생하며 선천성 내분비 질환 중 가장 흔한 것으로 알려져 있다. 본 질환은 갑상샘 발달 과정의 결함으로 인한 갑상샘 형성 부전 또는 호르몬 합성 장애로 인해 가장 흔히 발생한다. 이는 대부분 산발성으로 발생하나 갑상샘 형성 부전의 2%정도에서 가족성으로 발생하기도 하며 유기화 결함에 의한 갑상샘 기능 저하증은 열성으로 유전된다. 본 질환과 관련된 후보 유전자들은 갑상샘 형성 부전 군과 갑상샘 호르몬 합성 장애 군 등 크게 두 군으로 나뉜다. 갑상샘 형성 부전과 관련된 유전자는 비증후군성에 속하는 것으로 TSHR 유전자가 있고 여러 다른 복합적 기형을 동반한 증후군성에 속하는 것으로 Gsa 유전자 및 갑상샘 전사 인자 유전자(TTF-1, TTF-2, Pax-8) 등이 있다. 호르몬 합성장애와 관련된 것으로 TPO와 TG 유전자가 언급되었고 근래 PDS, NIS와 THOX2 유전자가 소개되었다. 또한 iodothyronine 이동 결함과 관련되어 심각한 신경학적 후유증을 동반할 수 있는 갑상샘 기능 저하증에 대한 유전적 근거가 제시되었다.

• Journal of Communications and Networks
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• 제13권5호
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• pp.481-493
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• 2011

Multiple-input multiple-output (MIMO) technology provides high data rate and enhanced quality of service for wireless communications. Since the benefits from MIMO result in a heavy computational load in detectors, the design of low-complexity suboptimum receivers is currently an active area of research. Lattice-reduction-aided detection (LRAD) has been shown to be an effective low-complexity method with near-maximum-likelihood performance. In this paper, we advocate the use of systolic array architectures for MIMO receivers, and in particular we exhibit one of them based on LRAD. The "Lenstra-Lenstra-Lov$\acute{a}$sz (LLL) lattice reduction algorithm" and the ensuing linear detections or successive spatial-interference cancellations can be located in the same array, which is considerably hardware-efficient. Since the conventional form of the LLL algorithm is not immediately suitable for parallel processing, two modified LLL algorithms are considered here for the systolic array. LLL algorithm with full-size reduction-LLL is one of the versions more suitable for parallel processing. Another variant is the all-swap lattice-reduction (ASLR) algorithm for complex-valued lattices, which processes all lattice basis vectors simultaneously within one iteration. Our novel systolic array can operate both algorithms with different external logic controls. In order to simplify the systolic array design, we replace the Lov$\acute{a}$sz condition in the definition of LLL-reduced lattice with the looser Siegel condition. Simulation results show that for LR-aided linear detections, the bit-error-rate performance is still maintained with this relaxation. Comparisons between the two algorithms in terms of bit-error-rate performance, and average field-programmable gate array processing time in the systolic array are made, which shows that ASLR is a better choice for a systolic architecture, especially for systems with a large number of antennas.

• 자원환경지질
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• 제8권4호
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• pp.175-182
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• 1975

본 연구는 양양(襄陽) 철광산(鐵鑛山) 의 철(鐵)을 부존(賦存)하고 있는 각섬석질암(角閃石質岩)의 성인(成因) 규명을 목적으로, 습식(濕式) 및 방출분광분석적(方出分光分析的) 방법을 통하여 얻은 18개의 주성분(主成分) 및 희유성분(稀有成分)의 data를 각종 Niggli 도표에 적용시키고 variaticn trend를 검토한 결과이다. 지금까지의 각 대륙(大陸)에 분포하는 각섬석질암(角閃石質岩)의 화학적(化學的)인 연구결과로는 거의 모든 각섬석질암이 변성퇴적암류(變成堆積岩類)의 형태로 산출될지라도 화성기원(火成起源)으로 밝혀져 왔으나 양양(襄陽) 철광산(鐵鑛山)의 함철(含鐵) 각섬석질암(角閃石質岩)은 준일각섬석질암(準一角閃石質岩), 특히 pelite-carbonate mixture의 특성(特性)을 뚜렷하게 보여준다. 즉 Niggli 값을 사용한 각 도면에서 본 연구의 대상이 된 시료들은 분산(分散)된 분포(分布) 및 퇴적(堆積)영역, 특히 pelite-carbonate mixture의 trend를 잘 따르고, Cr, Co 및 Ni의 함량이 매우 낮으며 Cr/mg, Co/mg 도포에서퇴적기원(堆積起源)의 특정인 negative trend를 뚜렷하게 나타낸다. 한편 높은 oxidation ratio의 값(>30)은 상기(上記) 결과를 더욱 뒷바침해준다. 이러한 모든 현상은 경기변성대(京畿變成帶)에서 퇴적기원(堆積起源)으로 판명된 준일각섬석질암(準一角閃石質岩)(소칠섭(蘇七燮), 1974) 이 갖는 특성과 유사하다.