• Title/Summary/Keyword: National Basic S&E Research

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Synthesis and Evaluation of Antitumor Activity of 2- and 6-[(1,3- Benzothiazol-2-yl)aminomethyl]-5,8-dimethoxy-1,4-naphthoquinone Derivatives

  • Chung, Yong-Seog;Shin, Young-Kook;Zhan, Chang-Guo;Lee, Sung-Duck;Cho, Hoon
    • Archives of Pharmacal Research
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    • v.27 no.9
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    • pp.893-900
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    • 2004
  • 2- or 6-Substituted BZT-N derivatives were synthesized, and their cytotoxic activity against can-cer L1210 and SNU-1 cells was examined. The antitumor action was also assessed in mice bearing S-180 cells in peritoneal cavity. In a comparison, it was found that 6-substituted BZT-N derivatives exhibited higher potencies in both bioactivities than 2-substituted BZT-N derivatives against L1210 cells in in vitro and S-180 in vitro tests exception of compound 36. Interestingly, it was observed that 2-substituted compound 36, which has methyl group at RI position, exhib-ited a better antitumor activity than 6-substituted compounds against L1210 and SNU-1 in vitro. The EDso value of 2-substituted compound 36 against L1210 was found to be comparable to the EDso value of adriamycin and was even better against the solid cancer cell line SNU-1. It was also observed that 2-substituted compound 36 showed better antitumor activity in mice bearing S-180 cells in the peritoneal cavity. The T/C (%) value of 2-substituted compound 36 was simi-lar to that of adriamycin. Quantitative structure-activity relationship (QSAR) tests reveal that the experimental E $D_{50}$ values against SNU-1 closely correlate with both the calculated HOMO ener-gies ( $E_{HOMO}$) and the measured H-NMR chemical shift of 3-H ($\delta$$_{H}$). The results suggests that a compound having higher $E_{HOMO}$ and $\delta$$_{H}$ values usually should have a lower E $D_{50}$ (SNU-1) value.lue.lue.lue.

Monitoring of III-V semiconductor surface by In-situ Surface PhotoAbsorption

  • Kim, T. J.;Kim, Y. D.;H. Hwang;E. Yoon
    • Journal of the Korean Vacuum Society
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    • v.12 no.S1
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    • pp.79-82
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    • 2003
  • We present the investigation on P- and As-desorption process from the (001) InP surface in metal organic chemical vapor deposition using surface photoabsorption (SPA). The monochromatic SPA signal showed rapid initial increase to reach In-stabilized surface value after $PH_3$ was turned off, but in case of As-desorption, the signal showed clear existence of a metastable state after the $AsH_3$ was turned off. The SPA spectra at each stable surfaces were taken to confirm the interpretation. This result indicates that the As-desorption process should be understood as a two-step process, in contrast to P-desorption of one-step process.

Improvement of Lutein and Zeaxanthin Production in Mychonastes sp. 247 by Optimizing Light Intensity and Culture Salinity Conditions

  • Seong-Joo Hong;Kyung June Yim;Young-Jin Ryu;Choul-Gyun Lee;Hyun-Jin Jang;Ji Young Jung;Z-Hun Kim
    • Journal of Microbiology and Biotechnology
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    • v.33 no.2
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    • pp.260-267
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    • 2023
  • In this study, we sought to improve lutein and zeaxanthin production in Mychonastes sp. 247 and investigated the effect of environmental factors on lutein and zeaxanthin productivity in Mychonastes sp. The basic medium selection and N:P ratio were adjusted to maximize cell growth in one-stage culture, and lutein and zeaxanthin production conditions were optimized using a central composite design for two-stage culture. The maximum lutein production was observed at a light intensity of 60 μE/m2/s and salinity of 0.49%, and the maximum zeaxanthin production was observed at a light intensity of 532 μE/m2/s and salinity of 0.78%. Lutein and zeaxanthin production in the optimized medium increased by up to 2 and 2.6 folds, respectively, compared to that in the basic medium. Based on these results, we concluded that the optimal conditions for lutein and zeaxanthin production are different and that optimization of light intensity and culture salinity conditions may help increase carotenoid production. This study presents a useful and potential strategy for optimizing microalgal culture conditions to improve the productivity of lutein and zeaxanthin, which has applications in the functional food field.

Component Comparison in Different Growth Stages and Organs of Saururus chinensis $B_{AILL}$. (삼백초의 생육 시기 및 부위별 성분 함량 비교)

  • Lee, Seong-Tae;Park, Jeong-Min;Lee, Hee-Kyoung;Kim, Man-Bae;Cho, Ju-Sik;Heo, Jong-Soo
    • Korean Journal of Medicinal Crop Science
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    • v.8 no.4
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    • pp.312-318
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    • 2000
  • To obtain the basic information for commercial process and high quality production of Saururus chinensis, useful components were determined at different growth stages and organs. The contents of quercetin, quercitrin and tannin at different growth stages were decreased before flowering time but slightly increased after flowering. The contents of quercetin, quercitrin and tannin collected on July 26 were 5.72, 5.45g/kg and 1.5%, respectively. The contents of quercetin, quercitrin and tannin were the highest in white leaf, leaf and flower, respectively.

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Human Apolipoprotein E2 Transgenic Mice Show Lipid Accumulation in Retinal Pigment Epithelium and Altered Expression of VEGF and bFGF in the Eyes

  • Lee, Sung-Joon;Kim, Jeong-Hun;Kim, Jin-Hyoung;Chung, Mi-Ja;Wen, Qingcheng;Chung, Hum;Kim, Kyu-Won;Yu, Young-Suk
    • Journal of Microbiology and Biotechnology
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    • v.17 no.6
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    • pp.1024-1030
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    • 2007
  • We investigated the human apolipoprotein E2 (apoE2) transgenic mouse as an animal model system for age-related macular degeneration (AMD). Transgenic mice expressing human apoE2 and C57BL/6J mice were fed normal chow or a high-fat diet for 4 weeks. Eyes were collected from the mice and lipid deposits in retinal pigment epithelium (RPE) were assessed using electron microscopy. The expressions of apoE, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and pigment-epithelium derived factor (PEDF), which are molecular markers for angiogenesis, were assessed with immunohistochemistry. Eyes from apoE2 mice, regardless of diet, contained lipid accumulation in RPE under electron microscopy, whereas control C57BL/6J eyes did not. Lipid accumulation was found predominantly in the RPE and the Bruch's membrane and increased in the eyes of apoE2 mice after one month of a high-fat diet ($8{\pm}2\;per\;50{\mu}m^2$ for normal chow and $11{\pm}2\;per\;50\;{\mu}m^2,\;p<0.05)$. ApoE expression was similar in the apoE2 and control mice; however, VEGF and bFGF were overexpressed in the retinal pigment epithelium of apoE2 eyes compared with control eyes, and PEDF expression was slightly decreased. These expression patterns of VEGF, bFGF, and PEDF suggest angiogenesis is progressing in apoE2 eyes. In conclusion, the eyes of apoE2 mice develop typical lipid accumulations, a common characteristic of AMD, making them a suitable animal model for AMD. The expression profile of VEGF and bFGF on the retinal pigment epithelium suggests that apoE2 may induce neovascularization by altering angiogenic cytokines.

Modulation of the Time Course of Cardiac Chronotropic Responses during Exposure to Affective Pictures

  • Estate M. Sokhadze;Lee, kyung-Hwa;Lee, Jong-Mee;Oh, Jong-In;Sohn, Jin-Hun
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2000.04a
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    • pp.290-300
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    • 2000
  • One of the most important topics in attentional and emotional modulation of cardiac responses is time course of cardiac chronotropic response. The reason lies in dual innervation of heart, which leads to occurrence of several phases of cardiac response during exposure to affective stimuli, determined by the balance of sympathetic and parasympathetic influences. Cardiac chronotropic reactivity thus represents quite effective measure capable to trace the moment when attending and orienting processes (i.e., sensory intake of stimulus) prime relevant behavioral response (ile., emotion with approach or avoidance tendencies). The aim of this study was to find the time course of heart rate (HR) responses typical for negative (disgust, surprise, fear, anger) and positive (happiness, pleasant erotic) affective pictures and to identify cardiac response dissociation for emotions with different action tendencies such as "approach" (surprise, anger, happiness) and "avoidance" (fear, sadness, disgust). Forty college students participated in this study where cardiac responses to slides from IAPS intended to evoke basic emotions (surprise, fear, anger, sadness, disgust, happiness, pleasant-erotic). Inter-beat intervals of HR were analyzed on every 10 sec basis during 60 sec long exposure to affective visual stimuli. Obtained results demonstrated that differentiation was observed at the very first 10s of exposure (anger-fear, surprise-sad, surprise-erotic, surprise-happiness paris), reaching the peak of dissociation at 30s (same pairs plus surprise-disgust and surprise-fear) and was still effective for some pairs (surprise-erotic, surprise-sad) even at 50s and 60s. discussed are potential cardiac autonomic mechanisms underlying attention and emotion processes evoked by affective stimulation and theoretical considerations implicated to understand the role of differential cardiac reactivity in the behavioral context (e.g., approach-avoidance tendencies, orienting-defense responses).

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A Study on e-learning Contents Opening Information for Distribution Industry Labor Competence (유통산업 인력 역량강화를 위한 이러닝 콘텐츠 정보공개 항목에 관한 연구)

  • Kim, Yong
    • Journal of Distribution Science
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    • v.15 no.8
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    • pp.65-73
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    • 2017
  • Purpose - Although e-learning has this advantage, currently many organizations have failed to recognize the necessity for basic e-learning educational training. It follows that practitioners working in the above organizations face the difficulty of having to find educational training processes of boosting their capabilities by themselves, rather than being able to utilize the educational training processes offered by e-learning. So of their own accord, learners have considered the necessity of information relating to being able to choose between high quality educational training processes. The purpose of this study is to propose opening e-learning content information for enabling an efficient choice of learning processes related to e-learning. Research design, data, and methodology - To pinpoint the items of e-learning content information, the study was initiated according to the following process. First, information relating to e-learning content (offered on e-learning websites) was researched. Second, based on the items of information which emerged from the research, selection and validity verification took place with 5 e-learning specialists as the subjects. Third, the opinions of adult learners at K University were collated relating to the items of information which emerged from the research. Results - The e-learning content information was comprised of 16 items in order to improve the choosing process for learner's e-learning contents. The analysis results showed that when learners were choosing e-learning processes, the most highly considered item was 'mobile support' (4.35). Following this (in order) were 'tuition fees' (4.30), 'certificate issuing' (4.23), and 'awareness of educational institution' (4.18). The least considered items were 'recruiting learners' (3.01) and 'tutor support' (3.18). Conclusions - The 16 items of e-learning content information in this study, were deemed to be helpful to learners in providing them with a choice of desirable e-learning process when this process was offered to them. Following this, there is a need for service institutions offering e-learning processes to make public the information suggested by this study. Research into educational methods additionally points to a necessity for not only e-learning forms, but also offline educational methods and a combination of blended learning to be offered and run parallel to e-learning.

The top 10 most-cited articles on the management of fractured instruments: a bibliometric analysis

  • Mishra, Lora;Kim, Hyeon-Cheol;Singh, Naomi Ranjan;Rath, Priti Pragati
    • Restorative Dentistry and Endodontics
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    • v.44 no.1
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    • pp.2.1-2.6
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    • 2019
  • Objectives: The purpose of this research was to identify the top 10 most-cited articles on the management of fractured or broken instruments and to perform a bibliometric analysis thereof. Materials and Methods: Published articles related to fractured instruments were screened from online databases, such as Web of Science, Scopus, PubMed, and ScienceDirect, and highly cited papers, with at least 50 citations since publication, were identified. The most-cited articles were selected and analysed with regard to publication title, authorship, the journal of publication, year, institution, country of origin, article type, and number of citations. Results: The top 10 most-cited articles were from various journals. Most were published in the Journal of Endodontics, followed by the International Endodontic Journal, and Dental Traumatology. The leading countries were Australia, Israel, Switzerland, the USA, and Germany, and the leading institution was the University of Melbourne. The majority of articles among the top 10 articles were clinical research studies (n = 8), followed by a basic research article and a non-systematic review article. Conclusions: This bibliometric analysis revealed interesting information about scientific progress in endodontics regarding fractured instruments. Overall, clinical research studies and basic research articles published in high-impact endodontic journals had the highest citation rates.

A proton induced X-ray emission (PIXE) analysis of concentration of major/trace and toxic elements in broiler gizzard and flesh of Tehsil Gujar Khan area in Pakistan

  • Nadeem, Khawar;Hussain, Javaid;Haq, Noaman Ul;Haq, A. Ul;Akram, Waheed;Ahmad, Ishaq
    • Nuclear Engineering and Technology
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    • v.51 no.8
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    • pp.2042-2049
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    • 2019
  • Ten gizzard and three flesh samples of the broiler were collected from different locations in Tehsil Gujar Khan District Rawalpindi, Pakistan. The samples were dried, crushed and ground. Pellets were prepared by pressing the powder of the samples and that of the Bovine liver 1577c reference material obtained from NIST, USA. Proton induced X-ray emission (PIXE) installed at National Center for Physics, Islamabad, Pakistan has been used as a reliable and improved technique to determine concentration of various major/trace and toxic elements e.g. S, Cl, K, Ca, Cl, Fe, Cu, Mn, Co, Zn, Ti, Cd, Ga, Cr, V and Ni, in the Gizzard and Flesh samples of the broiler. The concentrations of all the detected elements in the samples are statistically significant. The certified and measured values of the elements in the reference material were in agreement with each other within a deviation of 7%. S, Cl, K and Ca are within tolerable limits and are good for human consumption. Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn were more than the acceptable limits of World Health Organization, WHO whereas Ga, As, Sn, Sb and Pb are not detected in most of the samples.

ADVANCED TEST REACTOR TESTING EXPERIENCE - PAST, PRESENT AND FUTURE

  • Marshall Frances M.
    • Nuclear Engineering and Technology
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    • v.38 no.5
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    • pp.411-416
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    • 2006
  • The Advanced Test Reactor (ATR), at the Idaho National Laboratory (INL), is one of the world's premier test reactors for providing the capability for studying the effects of intense neutron and gamma radiation on reactor materials and fuels. The physical configuration of the ATR, a 4-leaf clover shape, allows the reactor to be operated at different power levels in the comer 'lobes' to allow for different testing conditions for multiple simultaneous experiments. The combination of high flux (maximum thermal neutron fluxes of 1E15 neutrons per square centimeter per second and maximum fast [E>1.0 MeV] neutron fluxes of 5E14 neutrons per square centimeter per second) and large test volumes (up to 122 cm long and 12.7 cm diameter) provide unique testing opportunities. The current experiments in the ATR are for a variety of test sponsors - US government, foreign governments, private researchers, and commercial companies needing neutron irradiation services. There are three basic types of test configurations in the ATR. The simplest configuration is the sealed static capsule, which places the capsule in direct contact with the primary coolant. The next level of experiment complexity is an instrumented lead experiment, which allows for active control of experiment conditions during the irradiation. The most complex experiment is the pressurized water loop, in which the test sample can be subjected to the exact environment of a pressurized water reactor. For future research, some ATR modifications and enhancements are currently planned. This paper provides more details on some of the ATR capabilities, key design features, experiments, and future plans.