Liquid chromatographic resolution of 1-aryl-1,2,3,4-tetrahydroisoquinolines on a chiral stationary phase based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid

Lee, A.,Choi, H.J.,Jin, K.B.,Hyun, M.H. Elsevier 2011 Journal of chromatography A Vol.1218 No.26

A liquid chromatographic chiral stationary phase (CSP) based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid was applied for the first time to the resolution of biologically important 1-aryl-1,2,3,4-tetrahydroisoquinolines. The unusual resolution of cyclic secondary amino compounds on a chiral crown ether-based CSP was quite successful with the use of a mixture of methanol-acetonitrile-triethylamine at a ratio of 30/70/0.5 (v/v/v) as a mobile phase. From the chromatographic behaviours for the resolution of seven 1-aryl-1,2,3,4-tetrahydroisoquinolines, the steric bulkiness of the 1-phenyl ring at the chiral center of analytes was concluded to play an important role in the chiral recognition.

Fast motion estimation using priority-based inter-prediction mode decision method in high efficiency video coding

SPEINGER SCEINCE + BUSINESS MEDIA 2016 JOURNAL OF REAL TIME IMAGE PROCESSING Vol.12 No.2

<P>The latest video coding standard, high efficiency video coding (HEVC), is developed to acquire a more efficient coding performance than the previous standard, H.264/AVC. To achieve this coding performance, elaborate coding tools were implemented in HEVC. Although those tools show a higher coding performance than H.264/AVC, the encoding complexity is heavily increased. Especially, motion estimation (ME) requires the most computational complexity because that is always performed on three inter-prediction modes: uni-directional prediction in List 0 (Uni-L0), uni-directional prediction in List 1 (Uni-L1), and bi-prediction (Bi). In this paper, we propose a priority-based inter-prediction mode decision method to reduce the complexity of ME caused by inter-prediction. The proposed method computes the priorities of all inter-prediction modes and decides whether ME is performed or not. Experimental results show that the proposed method reduces the computational complexity of ME up to 55.51% while maintaining similar coding performance compared to HEVC test model (HM) version 10.1.</P>

Characterization of a thermostable glycoside hydrolase family 36 α-galactosidase from Caldicellulosiruptor bescii

Lee, A.,Choi, K.H.,Yoon, D.,Kim, S.,Cha, J. Society for Bioscience and Bioengineering, Japan ; 2017 Journal of bioscience and bioengineering Vol.124 No.3

<P>The putative gene cluster involved in the degradation of the raffinose family oligosaccharides (RFO) was identified in Caldicellulosiruptor bescii. Within the cluster, the gene encoding a putative alpha-galactosidase (CbAga36) was cloned and expressed in Escherichia coli. Size exclusion chromatography of the purified rCbAga36 indicated that the native form was a tetramer. Its primary sequence was similar to the family of glycoside hydrolase 36. The purified recombinant CbAga36 (rCbAga36) was optimally active at pH 5.0 and 70 degrees C and had a half-life of 15 h and 10 h at 70 degrees C and 80 degrees C, respectively. rCbAga36 showed high activity with the artificial substrate (p-nitrophenyl cc-D-galactopyranoside, pNPaGal) exhibiting lower Km and higher kat than natural substrates such as melibiose and raffinose. Although rCbAga36 demonstrated preferential activity toward the hydrolysis of RFO such as raffinose and stachyose, it did not degrade the polymeric galactomannans. Our results imply that CbAga36 may play a role in the degradation of RFO, transported into the cytoplasm via a transporter into galactose, which is further utilized as an energy source in C. bescii. Furthermore, its ability to synthesize novel oligosaccharides by transglycosylation renders this enzyme potentially useful for the production of dietary oligosaccharides with novel function. (C) 2017, The Society for Biotechnology, Japan. All rights reserved.</P>

Leakage of radioactive materials from particle accelerator facilities by non-radiation disasters like fire and flooding and its environmental impacts

Lee, A,Jung, N S,Mokhtari Oranj, L,Lee, H S Institute of Physics Publishing Ltd 2018 Journal of Physics: Conference Series Vol.1046 No.-

Vibrio vulnificus infection induces the maturation and activation of dendritic cells with inflammatory Th17-polarizing ability

Lee, A.,Lim, H. X.,Kim, M. S.,Cho, D.,Jang, K. K.,Choi, S. H.,Kim, T. S. UNKNOWN 2018 INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE Vol.41 No.1

Multifunctional resistive switching behaviors employing various electroforming steps

Lee, A.,Bae, Y.,Baek, G.,Chung, J.,Lee, S.,Im, H.,Hong, J. Royal Society of Chemistry 2016 Journal of Materials Chemistry C Vol.4 No.4

<P>We examine the electroforming-dependent multifunctional resistive switching features by operating a merged Pt/Ta2O5-x/Ta-Ta/Ta2O5-x/Pt switching device under particular bias and polarity conditions. The basic Pt/Ta2O5-x/Ta resistive switching cell comprising the completely merged device shows two different bipolar switching behaviors with an initial forming process under different bias polarities. Therefore, two switching elements can be merged in various ways to produce diverse functionalities such as asymmetric complementary resistive switching (CRS) and typical CRS, achieved through control of the forming process. A possible mechanism to explain the unique features observed is discussed in terms of bias-driven oxygen ion drift and Joule-heating-based filamentary path models. This work suggests a suitable electroforming route for advancing symmetric CRS characteristics.</P>

Incompletely condensed POSS-based spin-on-glass networks for impeccable ultra low-k integration

Lee, A.,Choi, S. S.,Oh, S.,Lee, H.,Kim, B.,Hwang, S.,Baek, K. Y. 20151 60 5 2015 Journal of Materials Chemistry C Vol.3 No.44

Effects of Literacy and Education on Semantic Fluency in the Korean Elderly

Jinkyung Leea(이진경),Yeonwook Kanga(강연욱) 한국언어청각임상학회 2016 Communication Sciences and Disorders Vol.21 No.4

배경 및 목적: 본 연구는 한국 노인들을 대상으로 문식성(literacy)과 교육수준이 의미 유창성에 미치는 효과를 확인하고 그 결과가 의미범주(동물, 가게물건)에 따라서 차이가 있는지 밝히고자 수행되었다. 방법: 306명의 정상노인(평균 나이 72.8±7.8세; 남자 151명, 여자 155명)이 연구에 참여하였고, 문식성과 교육수준에 따라서 7개 집단(비문해 집단, 무학/문해 집단, 저-초등 집단, 고-초등 집단, 중학교 집단, 고등학교 집단, 대학 집단)으로 분류되었다. 모든 연구 대상자들에게 의미 유창성검사(동물, 가게물건)를 실시하였다. 결과: 동물 범주에서는 비문해 집단과 무학/문해 집단 간 의미 유창성의 차이가 관찰되었으나, 가게물건 범주에서는 비문해 집단이 무학/문해 집단이나 저-초등 집단과 의미 유창성의 차이를 보이지 않았다. 또한 동물 범주에서는 무학/문해 집단부터 중학교 집단까지 유의한 수행차이가 관찰되지 않았고, 고등학교 집단과 대학 집단 간에도 수행차이가 발견되지 않았으나, 가게물건 범주에서는 고-초등 집단이 비문해 집단보다, 중학교 집단이 무학/문해 집단보다, 그리고 대학 집단이 고등학교 집단보다 우수한 수행을 보였다. 논의 및 결론: 본 연구의 결과는 동물 범주의 경우에는 교육수준보다 문식성이 의미 유창성에 더 큰 영향을 미치고, 가게물건 범주의 경우는 문식성보다 교육수준이 더 큰 영향을 미친다는 사실을 시사한다. Objectives: The present study was conducted to examine the effects of literacy and education on semantic fluency and to compare them to two semantic categories such as animal and supermarket. Methods: Normal healthy elderly (N=306; mean age: 72.8±7.8 years; 151 male, 155 female) participated in the study. The participants were classified into 7 groups: illiterate group (N=30), no schooling but literate group (N=40), lower grade of elementary school group (N=24), higher grade of elementary school group (N=55), middle school group (N=52), high school group (N=51), and college group (N=54). All of the participants were given the semantic (animal & supermarket) fluency test. Results: There was a significant group difference between the illiterate and no schooling but literate groups in the animal category, whereas no significant group difference was found between the illiterate and lower grade of elementary school groups in the supermarket category. In the animal category, there was no significant group difference between the no schooling but literate and middle school groups or between the high school and college groups, whereas the performance was better on the supermarket category test in the higher grade of elementary school than the illiterate groups, and in the middle school than no schooling but literate groups, and in the college than high school groups. Conclusion: The results suggest that literacy has a stronger influence on animal fluency while education has a stronger influence on supermarket fluency.

Development of Intentional Communicative Behavior in Korean Toddlers 12 to 30 Months

YoonKyoung Leea(이윤경),HyoJoo Leeb(이효주) 한국언어청각임상학회 2016 Communication Sciences and Disorders Vol.21 No.4

배경 및 목적: 영유아 시기의 의도적 의사소통행동 발달은 의사소통 발달의 기초가 되며, 추후 언어 발달과도 밀접한 관계를 갖는다. 본 연구는 12-30개월 사이의 영아들을 대상으로 의도적 의사소통행동 발달을 살펴보는 것을 목적으로 하였다 방법: 12-30개월 사이의 전형적 발달 영유아 41명을 대상으로 하였다. 참여 영유아는 6개월 간격의 세 연령 집단으로 구분하였으며, 각각 참가자는 12-18개월 13명, 19-24개월 14명, 25-30개월 14명이었다. 의도적 의사소통행동은 영유아와 양육자 간의 놀이 상황에서 수집된 10분간의 상호작용 행동표본을 분석하였으며, 분당 의도적 의사소통행동 빈도, 의도적 의사소통행동의 기능(행동통제적, 사회적 상호작용적, 동시주의적), 의도적 의사소통행동의 수단(몸짓, 발성, 몸짓 동반 발성, 언어, 몸짓 동반 언어)을 측정하였다. 측정된 결과는 일원분산분석과 이원분산분석, 단순 및 중다회귀분석으로 통계 분석하였다. 결과: 분당 의도적 의사소통행동 빈도는 연령에 따라 유의하게 증가하였다. 의사소통기능 범주별 사용 빈도는 동시주의와 사회적 상호작용 기능 범주에서 연령에 따라 유의한 증가를 보였으며, 기능 범주별 하위기능 유형 수는 동시주의에서만 연령에 따른 유의한 차이를 보였다. 의사소통수단에서는 몸짓은 연령 증가에 따라 유의하게 감소한 반면, 몸짓 동반 언어와 언어의 사용은 연령에 따라 유의하게 증가하였다. 분당 의도적 의사소통행동 빈도와 동시주의 기능, 몸짓 동반 언어가 생활연령 및 언어발달연령을 유의하게 설명하는 것으로 나타났다. 논의 및 결론: 본 연구의 결과는 12-30개월 한국 영유아의 초기 의도적 의사소통행동 발달을 보여주며, 영유아 시기의 의도적 의사소통 발달 평가 및 중재에 활용할 수 있을 것이다. Objectives: The development of intentional communicative behaviors is closely related to later language development. This study aimed to examine the development of the intentional communicative behavior in Korean toddlers at 12 to 30 months. Methods: The participants were 41 typical developing Korean toddlers. The toddlers were classified by three age groups: 12–18 months, 19–24 months, and 25–30 months. A 10-minute behavior sample was obtained from each participant during interaction with their caregiver, from which the frequency of intentional communicative behaviors per minute, communicative functions (behavior regulatory, social interactional, and joint attentional functions), and means (gesture, vocalization, gesture with vocalization, verbal, verbal with gesture) of the behaviors were measured. Results: Results showed the following: intentional communicative behaviors per minute increased significantly with age. Analysis of communicative functions indicated that the rate of joint attentional and social interactional functions also significantly increased with age, however, in the number of sub-functions only increased in the joint attentional function. Analysis of communicative means showed that communicative gestures significantly decreased, but verbal communications with gestures and verbal means increased with age. The frequency of intentional communicative behaviors per minute, joint attentional functions, and verbal communications with gestures significantly predicted chronological age and language age. Conclusion: The results of this study help in understanding the development of intentional communicative behaviors in Korean toddlers during 12 to 30 months of age and have implications for assessing the communicative abilities in the toddler period and planning intervention for children with developmental language delay.

Effect of nicotine on orthodontic tooth movement and bone remodeling in rats

Sung-Hee Leea,Jung-Yul Chab,Sung-Hwan Choib,Baek-il Kimc,Jae-Kook Chad,Chung-Ju Hwang 대한치과교정학회 2021 대한치과교정학회지 Vol.51 No.4

Objective: To quantitatively analyze the effect of nicotine on orthodontic tooth movement (OTM) and bone remodeling in rats using micro-computed tomography and tartrate-resistant acid phosphatase immunostaining. Methods: Thirty-nine adult male Sprague-Dawley rats were randomized into three groups: group A, 0.5 mL normal saline (n = 9, 3 per 3, 7, and 14 days); group B, 0.83 mg/kg nicotine (n = 15, 5 per 3, 7, and 14 days); and group C, 1.67 mg/kg nicotine (n = 15, 5 per 3, 7, and 14 days). Each animal received daily intraperitoneal injections of nicotine/saline from the day of insertion of identical 30-g orthodontic force delivery systems. A 5-mm nickel-titanium closed-coil spring was applied between the left maxillary first molar (M1) and the two splinted incisors. The rate of OTM and volumetric bone changes were measured using micro-computed tomography. Osteoclasts were counted on the mesial alveolar bone surface of the distobuccal root of M1. Six dependent outcome variables, including the intermolar distance, bone volume fraction, bone mineral density, trabecular thickness, trabecular volume, and osteoclast number, were summarized using simple descriptive statistics. Nonparametric Kruskal-Wallis tests were used to evaluate differences among groups at 3, 7, and 14 days of OTM. Results: All six dependent outcome variables showed no statistically significant among group-differences at 3, 7, and 14 days. Conclusions: The findings of this study suggest that nicotine does not affect OTM and bone remodeling, although fluctuations during the different stages of OTM in the nicotine groups should be elucidated in further prospective studies. [Korean J Orthod 2021;51(4):282-292]