• Molecular & Cellular Toxicology
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• 제5권1호
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• pp.14-22
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• 2009

In vitro cytotoxicity of 23 alkyl phenols (APs) on human cervical cancer cell lines (HeLa) was determined using the lactate dehydrogenase (LDH) cytotoxicity assay. Two different sets of descriptors were used to construct the calibration model based on Genetic Algorithm-Multiple Linear Regression (GA-MLR) based on the experimental data. A statistically robust Structure-Activity Relationships (QSAR) model was achieved ($R^2$=95.05%, $Q^2_{LOO}$=91.23%, F=72.02 and SE= 0.046) using three Dragon descriptors based on Me (0D-Constitutional descriptor), BELp8 (2D-Burden eigenvalue descriptor) and HATS8p (3D-GETAWAY descriptor). However, external validation could not fully prove its validity of the selected QSAR in characterization of the cytotoxicity of APs towards HeLa cells. Nevertheless, the cytotoxicity profiles showed a finding that 4-n-octylphenol (4-NOP), 4-tert-octyl-phenol (4-TOP), 4-n-nonylphenol (4-NNP) had a more potent cytotoxic effect than other APs tested, inferring that increased length and molecular bulkiness of the substituent had important influence on the LDH cytotoxicity.

• Food Science and Biotechnology
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• 제14권5호
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• pp.651-655
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• 2005

Enzymatic hydrolysis of shark (Squatina oculata) cartilage (SC) was optimized by response surface methodology (RSM) for chondroitin sulfate (CS) preparation. Among 11 commercial proteases, Maxazyme NNP showed highest productivity (CS yield per enzyme cost) of CS. Optimal hydrolysis conditions determined by RSM were 1.63% and 2.87 hr for enzyme concentration and hydrolysis time ($r^2\;=\;0.9527$, p<0.0l), respectively and highest yield of hydrolysate under the conditions was 42.3%. The yield ($43.1{\pm}2.1%$) and CS content ($24.8{\pm}0.1%$) of hydrolysate at optimal condition verified statistical optimization of SC enzymatic hydrolysis was valid.

• 전자공학회논문지
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• 제54권3호
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• pp.63-69
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• 2017

NNPS(normalized noise power spectrum)는 획득한 x선 영상에서 평판형 방사선 디텍터의 잡음 특성을 spectrum을 관찰하기 위해 측정한다. 그러나 NNPS 측정은 획득한 영상에 따라 일관적이지 못한 성질을 가지고 있어서 안정된 측정이 필요하다. 디텍터의 NNPS 측정은 표본 periodogram을 구하여 평균을 내는 방법을 사용하는데, 일반적으로 표본의 개수를 충분히 늘리면 정확하면서 안정된 값을 구할 수 있다. 본 논문에서는 periodogram과 같은 표본 spectrum의 평균으로 유한한 개수의 영상이 주어졌을 때 일관적이고 효율적인 NNPS 값을 제공 할 수 있는 두 가지 방법을 제안하고 그 성능을 비교하고 분석했다. 실제 두 종류의 방사선 디텍터로부터 획득한 x선 영상을 사용하여 제안한 방법을 실험하였으며, 주어진 영상을 사용하여 표본 spectrum의 최대 가지 수를 갖는 조합으로 NNPS를 구하고 평균을 내는 방법이 기존 방법에 비하여 안정된 NNPS 측정이 가능함을 보였다.

• 비파괴검사학회지
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• 제28권1호
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• pp.9-15
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• 2008

증기발생기 전열관에 생성되는 투자율변화에 의해 야기되는 신호왜곡 문제를 해결하기 위한 새로운 탐촉자를 개발하였다. 고리 1 호기 폐전열관에 생성된 자성상을 분리하여 자기이력곡선을 측정하였으며, 자성상이 생성되는 원인을 규명하기 위하여 고온 인장 시험을 수행하였다. 전산모사를 이용하여 탐촉자의 자정상 탐지조건을 결정하였으며, 디지털 신호전송을 위하여 신호처리용 전자회로를 소형화하여 탐촉자 속에 삽입하였다. 본 연구에서 개발된 신형 탐촉자를 이용하여 PVC 신호와 니켈 슬리빙 부위의 결함을 측정하였다. 신형 탐촉자는 보빈 탐촉자와 같이 고속으로 결함을 측정 할 수 있으며, 증기발생기 전열관의 탐상속도와 결함 탐지의 신뢰성을 증진시킬 수 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권5호
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• pp.675-681
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• 2002

Among Italian buffalo farmers, it is widely held that administering diets with high energy and protein concentrations is an effective way to increase milk production. In order to assess the validity of this opinion, we verified milk yield and physico-chemical characteristics from buffaloes that, from the $5^{th}$ month of lactation, were fed two total mixed rations (TMRs) which, given the same intake, should have led to satisfaction of protein requirements though with a slight energy deficit (diet A) or excessive amounts of energy and protein (diet B). Estimate of the energy and protein value of the diets and that of the corresponding requirements was carried out both by using two software programs derived from the Cornell Net Carbohydrate and Protein System (1992), and with the method set up by INRA researchers (1988). The results obtained show that the two diets administered did not result in significant changes to the quantity of milk produced. However, with Diet B the protein concentration in the milk was significantly (p<0.01) higher, although this was partly offset by the higher concentration (p<0.05) of non-protein nitrogen (NNP). The Group B buffaloes also showed significantly higher blood urea levels (p<0.01), with concentrations exceeding those considered physiological for lactating buffaloes. Finally, while administering Diet A the Body Condition Score (BCS) was close to 6.5 (Wagner et al., 1988), whereas in buffaloes which used Diet B it sometimes increased by over 0.5 points. As regards which of the two methods compared is more suitable for expressing dietary energy and protein value and corresponding requirements, we feel that due to the high variability in the Italian Mediterranean buffalo's milk production aptitude, it would be premature to express a judgement on methods which rest on a common scientific base and do not differ substantially.

• 대한수학교육학회지:학교수학
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• 제5권2호
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• pp.167-189
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• 2003

본 연구는 최근에 초등학교 수학에서 관심의 대상이 되고 있는 암산 지도의 교수학적 배경과 여러 나라의 암산 지도 실제를 살펴봄으로써 우리나라 초등학교 수학에서의 암산 지도에 대한 시사점을 도출하는 데 그 목적이 있다. 이러한 목적을 위하여 지난 10여 년 동안 계속 논의되어 온 수학적 소양의 의미와 이와 관련 해서 더욱 중시되고 있는 암산의 의미와 중요성뿐만 아니라 미국의 EM, 영국의 NNP, 네덜란드의 TAL, 독일의 mathe 2000 프로젝트에서 제안하고 있는 내용들을 통해 암산 지도의 실제 및 학생들의 암산 전략과 암산 지도에 도움이 되는 교수학적 모델을 살펴보았다. 마지막으로 앞에서 살펴본 이론적 배경을 바탕으로 우리나라 제 7차 수학 교과서의 암산 지도 내용을 암산 전략과 교수학적 모델에 비추어 분석하고 암산 지도를 위한 시사점을 논하였다.

• International journal of advanced smart convergence
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• 제10권1호
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• pp.197-208
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• 2021

The deer antler has been used as a major drug in oriental medicine for a long time. Recently, the demand for easy-to-take health functional foods is increasing due to economic development and changes in diet. As part of research on the development of functional materials for antlers, lactic acid fermentation of antler extract was performed. It was intended to develop a functional material with enhanced total polyphenol and flavonoid content and enhanced antioxidant activity. Lactic acid bacteria fermentation was performed by adding 4 types of lactic acid bacteria starter products, B. longum, Lb. Plantarum, Lb. acidophilus and mixture of 8 types of lactic acid bacteria to the antler water extract substrate, respectively. During the fermentation of lactic acid bacteria, the number of proliferation, total polyphenol and total flavonoid content, DPPH radical scavenging and antioxidant activity were quantified and evaluated. As a result of adding these four types of lactic acid bacteria to the antler water extract substrate, the number of lactic acid bacteria measured was 2.04~5.00×107. Meanwhile, a protease (Baciullus amyloliquefaciens culture: Maxazyme NNP DS) was added to the antler extract to decompose the peptide bonds of the contained proteins. Then, these four types of lactic acid bacteria were added and the number of lactic acid bacteria increased to 2.84×107 ~ 2.21×108 as the result of culture. The total polyphenol contents were 4.82~6.26 ㎍/mL in the lactic acid bacteria fermentation extracts, and after the reaction of protease enzyme and lactic fermentation, increased to 14.27~20.58 ㎍/mL. The total flavonoid contents were 1.52~2.21 ㎍/ml in the lactic acid bacteria fermentation extracts, and after the protease reaction and fermentation, increased to 5.59 ~ 8.11 mg/mL. DPPH radical scavenging activities of lactic acid bacteria fermentation extracts was 17.03~22.75%, but after the protease reaction and fermentation, remarkably increased to 32.82~42.90%.

• 천문학회지
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• 제56권1호
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• pp.59-73
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• 2023

The second generation of stars in the globular clusters (GCs) of the Milky Way (MW) exhibit unusually high N, Na, or Al, compared to typical Galactic halo stars at similar metallicities. The halo field stars enhanced with such elements are believed to have originated in disrupted GCs or escaped from existing GCs. We identify such stars in the metallicity range -3.0 < [Fe/H] < 0.0 from a sample of ~36,800 giant stars observed in the Sloan Digital Sky Survey and Large Sky Area Multi-Object Fiber Spectroscopic Telescope survey, and present their dynamical properties. The N-rich population (NRP) and N-normal population (NNP) among our giant sample do not exhibit similarities in either in their metallicity distribution function (MDF) or dynamical properties. We find that, even though the MDF of the NRP looks similar to that of the MW's GCs in the range of [Fe/H] < -1.0, our analysis of the dynamical properties does not indicate similarities between them in the same metallicity range, implying that the escaped members from existing GCs may account for a small fraction of our N-rich stars, or the orbits of the present GCs have been altered by the dynamical friction of the MW. We also find a significant increase in the fraction of N-rich stars in the halo field in the very metal-poor (VMP; [Fe/H] < -2.0) regime, comprising up to ~20% of the fraction of the N-rich stars below [Fe/H] = -2.5, hinting that partially or fully destroyed VMP GCs may have in some degree contributed to the Galactic halo. A more detailed dynamical analysis of the NRP reveals that our sample of N-rich stars do not share a single common origin. Although a substantial fraction of the N-rich stars seem to originate from the GCs formed in situ, more than 60% of them are not associated with those of typical Galactic populations, but probably have extragalactic origins associated with Gaia Sausage/Enceladus, Sequoia, and Sagittarius dwarf galaxies, as well as with presently unrecognized progenitors.

• 한국농림기상학회지
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• 제7권1호
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• pp.66-77
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• 2005

과정-중심적인 생지화학 모형인 BIOME-BGC을 이용해 기복이 심한 산림유역에서 미기후가 순일차생산성(NPP)의 시공간적 변화에 미치는 영향을 조사하였다. 임분규모에서의 물과 탄소순환과정에 대한 모형예측 을 검증하기 위하여 2000년부터 각각 낙엽활엽수림 (DBF)과 상록침엽수림(ENF)에서 현장 조사를 수행하였다. 모형예측은 지온, 토양수분, 토양호흡 등의 다양한 현장 측정치들과 높은 상관성을 보였다. 모형에서 예측한 NPP의 계절변화는 기온과 높은 상관성을 보였으나, 물 관련 인자들과는 통계적으로 유의한 상관성이 나타나지 않았다. 반면에 여러 인자 중에서, 강우빈도가 NPP의 연변화를 설명하는 가장 좋은 기후인자로 판명되었다 또한 DBF 임분보다 ENF 임분의 NNP가 강우빈도에 보다 민감한 것으로 나타났다. 공간적인 NPP 분포는 조사 유역에서 식생피복 및 지형의 기복에 따라 매우 이질적으로 나타났는데, NPP 이질성의 정도는 NPP의 절대량과 음의 상관관계를 보였다. 이러한 결과는 생육환경이 부적절할 때에 산림경관에서의 NPP 이질성이 커짐을 보여준다. 본 연구결과에 의하면 본 조사유역의 NPP는 연간 1,400mm 이상의 많은 강우에도 불구하고 식생이 이용할 수 있는 물의 양에 의해 제한 받는다는 것을 알 수 있었으며, 이러한 모형연구결과는 향후 현장조사를 통하여 검증할 필요가 있다.

• 한국간호교육학회지
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• 제5권1호
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• pp.97-105
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• 1999

Based on literature, status and role of the NP in America was reviewed. The process of developing NP program in America suggests us many things. In America, nurse practitioners have sustained a mutually beneficial status with their patients for over thirty years. Excel fence in academic education and clinical training will enable nurse practitioners to continue to provide quality health care. The magnitude changes in the health care system of the United States, the challange of providing real access of health care continues. Lack of access to adequate primary care was the driving force in the initial 1965 Federal Involvement in developing the NP role. In 1993 President Bill Clinton's health care reform initiative provided policy support for NPs as primary care providers. The Institute of Medicine explicitly recognized NPs as an integral part of the primary care team. In addition, several national reports recognized NPs as affordable, accessible, high-quality care providers. The recent passage of direct Medicare reimbursement for NPs reflected public policy statements coincided with and likely contributed to a growth spurt in the NP workforce. From 1965 to 1977 NP programs offered traditional primary care clinical tracks(adult, family, woman's health, and pediatrics) for relatively small clusters of students in a variety of institutional settings. From 1978 to 1990 these educational programs were incorporated into graduate schools of nursing. By 1990 the majority of NPs received educational preparation in master's-level nursing programs. A new emphases was placed on postmaster's NP programs designed for master's prepared clinical nurse specialists and nurse managers. he the health care system shifted hospital nursing resources toward community-based care, these master's -level nurses sought additional NP preparation. NP educational programs are defined as the educational structure in which one or more NP clinical tracks are offered. NP clinical tracks, in turn, offer curriculum and supervised clinical experiences that match standards in specific practice areas such as family(FNP), adult(AUP), geriatrics(GNP), pediatrics(PNP), women's health (WHNP), neonatal (NNP), and acute care(ACNP). There were indications that NP practice was expanding into new clinical areas as evidenced by new types of tracks, particularly in acute care and psychiatry. The increase in acute care NP students likely reflects the increased demand from hospitals and other acute care settings. In Korea, change of nurse's role into nurse practitioner's role may have many difficulties. The need of health consumer, policy support of government, approval of medical care team are all essential component. Every nursing personnel make effort to planning the new health care delivery system.