• Journal of Applied Biological Chemistry
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• 제43권4호
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• pp.235-239
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• 2000

A polysaccharide with antithrombin activity in Manda$^{(R)}& (PAM) was purified via procedures comprising three major steps, i.e. fractional precipitation with ethanol, anion exchange chromatography, and gel permeation chromatography. PAM showed a symmetrical peak on size exclusion HPLC, as assessed by refractive index, and behaved as a single band on cellulose acetate electrophoresis. The average molecular mass was estimated to be 222 kDa by gel filtration. PAM was found to be a sulfated heteropolysaccharide that contains sulfate group (20.5%, w/w) and uronic acid moiety (7.1 %, w/w) in addition to neutral sugar consisting of fucose, xylose, mannose, galactose, and glucose in a molar ratio of 1.00 : 0.35 : 0.28: 0.22 : 0.15. This polysaccharide appeared to inhibit blood coagulation via the intrinsic pathway in a dose-dependent pattern. The clotting of fibrinogen by thrombin was also significantly mitigated by the presence of PAM.

• Journal of the Korean Data and Information Science Society
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• 제22권4호
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• pp.741-753
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• 2011

마이크로어레이 유전자 발현데이터인 효모데이터를 이용하여 군집분석을 실시하였다. 모형기반 군집방법, K-평균법, 중앙값 중심분포 (PAM), 자기 조직화 지도 (SOM), 계층적 Ward 군집방법을 이용하여 군집화를 실시하고, 연결성 측도 (connectivity), Dunn지수, 실루엣 측도 (silhouette)를 이용하여 각 군집방법에 대한 유효성을 측정하고 군집분석 결과를 비교하고자한다.

• 한국조명전기설비학회지:조명전기설비
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• 제5권4호
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• pp.69-74
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• 1991

전력용 MOSFET를 사용한 새로운 PAM-PWM 인버터를 제안한다. 제안된 PAM-PWM 인버터의 출력파형을 이론과 실험적으로 연구했다. 선간전압파형은 기본파성분과 캐리아 주파수의 사이트벤드로 집중되어 저차 고주파는 출력파형에 포함되지 않았다. 각 인버터 아암은 2/3주기 동안 동작하지 않음으로 소자의 발열도 줄어든다. 그러므로 방열판의 감소에 의하여 인버터 시스템의 크기도 작아진다.

• 한국안전학회지
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• 제10권4호
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• pp.75-80
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• 1995

Spontaneous ignition characteristics of rice cracker were observed by preforming experiments at constant ambient temperature. As the results of the experiments, the critical spontaneous ignition temperature were exponentially decreased with the increase of ambient temperature. Type of combustion of rice cracker are smouldering combustion at low ignition temperature and flame combustion at high temperature. The rice cracker containing pam oil showed lower spontaneous ignition temperature than pure rice cracker because of oxidation heat of pam oil.

• 폴리머
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• 제31권4호
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• pp.356-367
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• 2007

세 종류의 아밀로오스 유도체들, 즉 에스터화도(DE)가 1.8에서 3의 범위에 있는 콜레스테릴옥시카본화 아밀로오스들(CAMs), DE가 0.3에서 3의 범위에 있는 (6-콜레스테릴옥시카보닐)펜타노화 아밀로오스들(PAMs), 그리고 완전치환 콜레스테릴옥시카본화 PAMs(CPAMs)들을 합성함과 동시에 이들의 열방성 액정 특성들을 검토하였다. $DE{\geq}2.6$인 CAM, DE=1.6인 PAM 그리고 모든 CPAMs는 쌍방성 콜레스테릭 상들을 형성하는 반면 $DE{\geq}2.2$인 PAMs는 단방성 콜레스테릭 상들을 형성하였다. $DE{\geq}2.2$인 PAMs 그리고 (6-콜레스테릴옥시카보닐)펜타노일 DE(DS)가 1.0 이상인 CPAMs는 온도상승에 의해 광학피치들(${\lambda}_{m'}s$)이 감소하는 콜레스테릭 상들을 형성하였다. 그러나 이들의 시료가 동일한 온도에서 나타내는 ${\lambda}_m$은 DS가 증가함에 따라 감소하였다. 한편, CAMs, DE=1.6인 PAM 그리고 DS=0.3인 CPAM은 콜레스테릭 상의 전 범위에서 반사색깔을 나타내지 않았다. 이러한 사실은 콜레스테릴 그룹에 의한 나선의 비틀림력은 콜레스테릴 그룹과 주사슬을 연결하는 스페이서의 길이와 DS에 민감하게 의존함을 시사한다. 아밀로오스 유도체들에서 관찰되는 콜레스테릭 상들의 열적 안정성 그리고 질서도는 DE 혹은 DS에 민감하게 의존하였다. 이들의 결과를 수소결합력, 주사슬의 가소화 그리고 주사슬로부터 곁사슬 그룹의 운동의 탈리의 차이와의 관련하에서 검토하였다.

• 펄프종이기술
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• 제47권4호
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• pp.46-53
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• 2015

Paper strengthening system of PVAm (polyvinylamine) has been used with strong negative charge polymer for electrostatic neutralization due to strong positive charge of PVAm. Recently, because of the controversy caused by the possibility of remaining PAM monomers in white water, a search for paper strength agent that can substitute for PAM was suggested. Therefore, this study was carried out to evaluate a dry strength polymer of PVAm. Starch and CMC were used as a substitute for PAM. The dual polymer system of PVAm and anionic charge control agent such as anionic starch or CMC (carboxy methyl cellulose) were found to be very effective as strength agent compared to the chemicals based on acrylamide.

• Interdisciplinary Bio Central
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• 제6권4호
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• pp.3.1-3.10
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• 2014

Amino acid substitution matrices are essential tools for protein sequence analysis, homology sequence search in protein databases and multiple sequence alignment. The PAM matrix was the first widely used amino acid substitution matrix. The BLOSUM series then succeeded the PAM matrix. Most substitution matrixes were developed by using the statistical frequency of substitution between each amino acid at blocks representing groups of protein families or related proteins. However, substitution of amino acids is based on the similarity of physiochemical properties of each amino acid. In this study, a new approach was used to obtain major physiochemical properties in multiple sequence alignment. Frequency of amino acid substitution in multiple sequence alignment database and selected attributes of amino acids in physiochemical properties database were merged. This merged data showed the major physiochemical properties through principle components analysis. Using factor analysis, these four principle components were interpreted as flexibility of electronic movement, polarity, negative charge and structural flexibility. Applying these four components, BAPS was constructed and validated for accuracy. When comparing receiver operated characteristic ($ROC_{50}$) values, BAPS scored slightly lower than BLOSUM and PAM. However, when evaluating for accuracy by comparing results from multiple sequence alignment with the structural alignment results of two test data sets with known three-dimensional structure in the homologous structure alignment database, the result of the test for BAPS was comparatively equivalent or better than results for prior matrices including PAM, Gonnet, Identity and Genetic code matrix.

• 말소리와 음성과학
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• 제6권4호
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• pp.27-36
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• 2014

This study provided longitudinal examination of the Chinese learners' acquisition of Korean vowels. Specifically, I examined the Chinese learners' Korean monophthongs /i, e, ɨ, ${\Lambda}$, a, u, o/ that were created at the time of 1 month and 12 months, tried to verify empirically how they learn by dealing with their mother tongue, and Korean vowels through dealing with pattern of the Perceptual Assimilation Model (henceforth PAM) of Best (Best, 1993; 1994; Best & Tyler, 2007) and the Speech Learning Model (henceforth SLM) of Flege (Flege, 1987; Bohn & Flege, 1992, Flege, 1995). As a result, most of the present results are shown to be similarly explained by the PAM and SLM, and the only discrepancy between these two models is found in the 'similar' category of sounds between the learners' native language and the target language. Specifically, the acquisition pattern of /u/ and /o/ in Korean is well accounted for the PAM, but not in the SLM. The SLM did not explain why the Chinese learners had difficulty in acquiring the Korean vowel /u/, because according to the SLM, the vowel /u/ in Chinese (the native language) is matched either to the vowel /u/ or /o/ in Korean (the target language). Namely, there is only a one-to-one matching relationship between the native language and the target language. In contrast, the Chinese learners' difficulty for the Korean vowel /u/ is well accounted for in the PAM in that the Chinese vowel /u/ is matched to the vowel pair /o, u/ in Korean, not the single vowel, /o/ or /u/.

• 한국농공학회논문집
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• 제65권4호
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• pp.1-10
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• 2023

As a result of climate change, non-point source pollution (NPS) from farmland with the steep slope during the rainy season is expected to have a significant impact on the water system. This study aimed to evaluate the effect of furrow mulching using alfalfa and PAM (Polyacrylamide) materials for each rainfall event, while considering the load characteristics of NPS. The study was conducted in Wanju-gun, Jeollabuk-do, in 2022, with a testbed that had a slope of 13%, sandy loam soil, and maize crops. The testbed was composed of four plots: bare soil (Bare), No mulching (Cont.), Vegetation mulching (VM), and PAM mulching (PM). Runoff was collected from each rainfall event using a 1/40 sampler and the NPS load was calculated by measuring the concentrations of SS, T-N, T-P, and TOC. During farming season, the reduction efficiency of NPS load was 37.1~59.5% for VM and 38.2~75.7% for PM. The analysis found that VM had a linear regression correlation (R²=0.28~0.86, P-value=0.01~0.1) with elapsed time of application, while PM had a quadratic regression correlation (R²=0.35~0.80, P-value=0.1). These results suggest that the selection of furrow mulch materials and the appropriate application method play a crucial role in reducing non-point pollution in farmland. Therefore, further studies on the time-series reduction effect based on the application method are recommended to develop more effective preemptive reduction technologies.

• 환경생물
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• 제30권3호
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• pp.210-218
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• 2012

일반적으로 많이 양식되는 방사무늬김(Porphyra yezoensis Ueda)에 대하여 방사무늬김 엽체의 형태적 특성, 탄소 및 질소 성분의 농도, 안정동위원소 비값, 광합성 효율을 방사무늬김 양식이 이루어 지고 있는 남서해역에서 조사를 하였다. 방사무늬김의 형태적 특성에 대해서 살펴보면 평균 엽장은 11.6~16.3 (13.8) cm, 평균 엽폭은 4.6~6.3 (5.4) cm이었고, 단위면적당 방사무늬김 엽체의 평균 엽중량은 $1.1{\sim}2.6(1.86)g\;DW\;m^{-2}$이었다. 단위면적당 Chl a 농도는 2.18~17.77 (평균 9.65) mg DW Chl a $m^{-2}$이었다. 방사무늬김의 탄소 농도는 $201{\sim}317(240)mg\;DW\;g^{-1}$이었고, 질소 농도는 $39.8{\sim}50.0(43.5)mg\;DW\;g^{-1}$이었으며, C/N비는 5.0~6.7 (5.5)이었다. 방사무늬김의 방사성 안정동위원소비 중에서 탄소 안정동위원소 비는 ${\delta}^{13}C$=-25.6‰ 에서 ${\delta}^{13}C$=-24.0‰ (평균 -24.7‰)의 값을 보였고, 질소 안정동위원소 비는 ${\delta}^{15}N$=1.3‰ 에서 ${\delta}^{15}N$=4.1‰ (평균 2.1‰)의 값을 보였다. PAM에 의한 해조류의 광합성 특성은 광합성 활동의 지시자로서 사용될 수 있다. 우리는 Diving-PAM을 이용하여 각 정점 해조류인 방사무늬김의 광합성율을 분석하였다. 최대양자수율은 0.46~0.55 (평균 0.52)로서 최대 양자수율의 변동은 정점간 큰 차이는 없었다. 최대상대전자전달률은 4.71~5.84 (평균 5.33) ${\mu}mol\;electrons\;m^{-2}\;s^{-1}$ 로서 최대양자수율과 비슷한 분포를 보였다. 기울기 (${\alpha}$)는 0.027~0.045 (평균 0.036)을 보였고, 전자전달을 위한 포화광은 지역에 따라서 일부 차이를 보였으나 $139{\sim}180(156){\mu}mol\;photons\;m^{-2}\;s^{-1}$이었다. 남서해역 방사무늬김 엽체의 탄소 및 질소 농도와 광합성 효율은 지역에 따른 큰 차이는 보이지 않았다. 광합성 특성은 낮은 최대양자수율과 최대 상대전자전달률로 인한 낮은 광합성 효율이 나타났다.