• Archives of Pharmacal Research
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• v.27 no.1
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• pp.25-30
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• 2004

Combinatorial homoserine lactone mixtures and individual products were obtained from the methionine-functionalized resin in solid-phase synthesis. The four-step process consisting of a coupling step of an N-Fmoc-L-methionine, deprotection of N-Fmoc group, N-coupling with a carboxylic acid, and cleavage reaction through a polymer supported strategy is described. Gas chromatography-mass selective detector (GC-MSD) techniques provide the most powerful methods for identifying both the combinatorial mixtures and individual products.

• Mass Spectrometry Letters
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• v.13 no.2
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• pp.27-34
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• 2022

Atmospheric aerosols have become a major environmental concern because of their adverse effects on human health, air quality, and climate change. Over the last few decades, several mass spectrometry (MS)-based techniques have been developed and applied in the field of atmospheric aerosol research. Particularly, real-time measurement of ambient aerosols using an aerosol mass spectrometer (AMS) has become one of the most powerful tools for aerosol chemistry. This review provides a brief description of AMS and its applications for understanding the physicochemical properties of atmospheric aerosols, as well as its sources and evolution processes.

• Korean Journal of Radiology
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• v.1 no.4
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• pp.175-184
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• 2000

Although surgical resection remains the best option as potentially curative therapy for hepatocellular carcinoma, radiofrequency thermal ablation has begun to receive much attention as an effective minimally invasive technique for the local control of unresectable malignant hepatic tumors. Most recent radiofrequency devices equipped with a powerful generator and larger needle electrode permit larger thermal lesions, up to 5 cm in diameter, with a single ablation. In this article, the author reviews the technical developments and early clinical results obtained with radiofrequency ablation techniques.

• Korean Journal of Child Studies
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• v.35 no.2
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• pp.1-23
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• 2014

The purpose of this research was to investigate the most critical variables in the school adjustment of youth. In addition, this research assessed the impact of variables according to the categorization of individual, family, and school domains. To acquire the effect sizes, published studies between 1990 and 2012 were reviewed systematically and synthesized by meta-analysis. The major findings were as follows. First, this study identified a total of 34 variables which can have an influence on the school adjustment of youth and confirmed that 24 of those variables are significant. The most crucial variable that can influence school adjustment is that of a teacher's support. The next most important variables are self-resilience, relationships with friends, and self-efficiency. Focusing on the categorized elements, self-resilience is the most critical variable in the individual domain, the parent-child relation is the most crucial variable in the family domain, and a teacher's support is the most powerful variable in the school domain. Based on these results, this study suggested a number of the indispensable components in interventions to improve the youth's adjustment in school.

• Food Science and Preservation
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• v.8 no.2
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• pp.217-223
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• 2001

The antimicrobial and glucosyltransferase(GTase) inhibition activity were searched for 30 species of various folk drugs and by products of food industry. Among them, two species, gallnut and red grape husk water extracts, were selected for the powerful antimicrobial and GTase inhibition activity. The polyphenol fractions of gallnut and red grape husk were showed very greater antimicrobial activity on both Gram(+) and (-), B. subtilis and E. coli. The minimum antimicrobial activity of gallnut polyphenol fraction were 1.0mg for B. subtilis and 3,0mg for E. coli. Red grape husk was 2.0mg for B. subtilis and 3.0mg for E coli. The polyphenol fractions of gall nut and red grape husk were showed powerful GTase inhibition activity. The concentrations of these fractions for 80% inhibition of GTase activity were 1.08$\times$10$\^$-3/mg/㎖ and 1.08$\times$10$\^$-2/mg/㎖, respectively. The most abundant compound in these fraction seems to be polyphenol derivatives. From these results, we think that the gallnut and the red grape husk polyphenol fraction had more antimicrobial and anti-plaque activities than artificial synthetic preservatives as an economic point of view.

• Research in Community and Public Health Nursing
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• v.15 no.3
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• pp.397-407
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• 2004

Purpose: In Korea, as the number of hypertensive worker grows, identifying the level of health promoting life style practice and related factors in hypertensive workers is becoming more and more important. Method: The subjects of this study were 195 hypertensive male workers in Korea. The data was collected during 3 months ranging from August 2003 to October 2003. The data was analyzed by descriptive statistics. t-test, ANOVA. Pearson's correlation coefficient and stepwise multiple regression by SAS 8.1 program. Results: It was found that there were significant differences between age, religion, medication, perceived health status, perceived benefits, internal health locus of control, powerful other health locus of control and health promoting life style practice. The most significant factor affecting the health promoting life style practice was internal health locus of control. The combination of internal health locus of control, specific self-efficacy, powerful other health locus of control, general self-efficacy accounted for 51.0% of the health promoting life style practice. Conclusion: The level of health promoting life style practice was very low, so it is urgent to manage and care for hypertensive male workers continuously and systemically with occupational health nurses. Based on the above results, cognitive perceptual characteristics should be considered when developing health education programs for hypertensive workers.

• Toxicological Research
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• v.29 no.2
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• pp.107-114
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• 2013

Mass spectrometry (MS) is a very powerful instrument that can be used to analyze a wide range of materials such as proteins, peptides, DNA, drugs, and polymers. The process typically involves either chemical or electron (impact) ionization of the analyte. The resulting charged species or fragment is subsequently identified by the detector. Usually, single mass uses source-induced dissociation (SID), whereas mass/mass uses collision-induced dissociation (CID) to analyze the chemical fragmentations Each technique has its own advantages and disadvantages. While CID is most effective for the analysis of pure substances, multiple-step MS is a powerful technique to get structural data. Analysis of veterinary drugs ampicillin, chloramphenicol, ciprofloxacin, and oxytetracycline serves to highlight the slight differences between SID and CID. For example, minor differences were observed between ciprofloxacin and oxytetracycline via SID or CID. However, distinct fragmentation patterns were observed for ampicllin depending on the analysis method. Both SID and CID showed similar fragmentation spectra but different signal intensities for chloramphenicol. There are several factors that can influence the fragmentation spectra, such as the collision energy, major precursor ion, electrospray mode (positive or negative), and sample homogeneity. Therefore, one must select a fragmentation method on an empirical and case-by-case basis.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1071-1071
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• 2001

Near-infrared spectroscopy (NIRS) is potentially a powerful and revolutionary technology for environmental analysis. It is supported by a large body of scientific and experiential knowledge. The instrumentation is well-developed, with easy-to-use, highly dependable instruments, but at the same time it is still developing, particularly with the production of more portable and rapid instruments, and more powerful software. NIRS is used globally in numerous industries for commodity analysis. Yet NIRS is largely unknown in the field of environmental chemistry and monitoring, and is not even routinely used in soil analysis, where the research literature on NIRS extends over four decades. Part of the explanation for the poor visibility of NIRS is the fact that NIRS is not routinely taught in Chemistry programs in universities, where most environmental chemists and environmental technicians are trained. This presentation examines the unique capabilities of NIRS, such as rapid, real-time analysis; analysis of whole samples; simultaneous analysis of multiple constituents; cost-effectiveness, and portability, as they match needs for analysis in several environmental areas. Examples of NIRS usage and published and unpublished results will be described for such areas as soil and sediment analysis; water quality monitoring; and nutrient loading in application of manures and sewage sludge (biosolids) to land. Present barriers to the use of NIRS in environmental analysis will be discussed. It is argued that emerging environmental problems and increasing attention to some traditional problems will enhance the application of NIRS in the future.

• Journal of Korea Game Society
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• v.10 no.5
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• pp.3-13
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• 2010

This paper focuses on the sequences between game performance, game experience, game generation. Present-day the game has powerful effects to form new human species as game generation. Especially, the experience game is important because it could have one of the most powerful effect by characteristics of own interface. First of all, this paper analyzes a experience of the experience game and researches the game-extended space. Secondly, We create concept of 'new game generation' in order to explain new human species on the experience game. So we can reveal the social meaning of accelerated present state by the experience game through this new analysis.

• Research in Community and Public Health Nursing
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• v.10 no.2
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• pp.307-319
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• 1999

The purpose of this study was to identify the major factors affecting performance in health promoting lifestyle of industrial workers. The subjects for this study 241 workers employed in S company in T city and were obtained by a convenience sample. Data were collected from March 2 to April 28. 1998. The collected data were analyzed using frequency. percent. mean. cronbach alpha. t-test. ANOVA. Person coefficients of correlation. Duncan test. stepwise multiple regression with an SPSS program. The results of this are summarized as follows. 1) The average score of performance in the health promoting lifestyle was 2.62. The variable with the highest degree of performance was harmonious relationship. whereas the one with the lowest degree was professional health maintenance. 2) Performance in the health promoting lifestyle was significantly correlated with self esteem, internal health locus of control and powerful others health locus of control. 3) Performance in the health promoting lifestyle was significantly correlated with such demographic variables as age. religion, education level. marital state. family number. types of dwelling. 4) The most important factor that affect performance in the health promoting lifestyle was powerful others health locus of control and self esteem. On the basis of this study. other factors affecting others health promoting lifestyle should be identified.