• Microbiology and Biotechnology Letters
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• v.45 no.4
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• pp.330-342
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• 2017

Statistical design of experiments was employed to optimize the media composition for the production of laccase from Bacillus sp. PK4. In order to find the key ingredients for the best yield of enzyme production from the selected eleven variables viz yeast extract, glucose, zinc sulphate, copper sulphate, potassium chloride, magnesium sulphate, calcium chloride, ferrous sulphate, sodium chloride, potassium dihydrogen phosphate ($KH_2PO_4$) and dipotassium hydrogen phosphate ($K_2HPO_4$), Plackett-Burman design was applied. The $MgSO_4$, $FeSO_4$, and $CuSO_4$ showed positive estimate, and their concentration optimized further. The steepest ascent method and Box-Behnken method revealed that 1.5 mM $MgSO_4$, 0.33 g/l $FeSO_4$ and 1.41 mM $CuSO_4$ were optimal for the laccase production by Bacillus sp. PK4. This optimization strategy leads to enhancement of laccase production from 2.13 U/ml to 40.79 U/ml. Agro-wastes residues replace the carbon source glucose in the optimized media namely sugarcane bagasse, wheat bran, rice husk, and groundnut shell, among these groundnut shells (117 U/ml) was found to enhance the laccase production significantly. The laccase produced by Bacillus sp. PK4 was found to have the potential to degrade persistent organic pollutant benzo[a]pyrene.

• The Journal of the Petrological Society of Korea
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• v.23 no.2
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• pp.145-152
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• 2014

Geological heritages can be defined conveniently as geological records worthy of conservation, and are represented in most cases by geological outcrops. So survey and evaluation of geologic outcrops are necessary for better conservation of geological heritages. As a measure to prevent potential destruction of geological heritages from various development projects, I propose construction of database based on survey and evaluation forms of geological outcrop, which can also be used for environmental impact assessment. The geological survey form consists of survey area, category, subcategory, location, dimension, geologic features, photo, description, and investigator. The evaluation form consists of evaluation category, detailed evaluation, comprehensive evaluation, and evaluation grade. The evaluation category is divided into academic aspect, education effect and landscape. The detailed evaluation items for academic aspects and education effect are representativeness, rarity, diversity and typicality, while those for geomorphology and landscape are peculiarity, aesthetics and naturalness. The evaluation grades are divided into five, where the first grade means a must of conservation.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.11
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• pp.4653-4658
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• 2015

Background: Palliative therapies have an important role in increasing the quality of healthcare and in dealing with physical and psychosocial problems due to cancer. We here aimed to evaluate the managerial perspectives and opinions of the hospital managers and clinical directors about specialized palliative care centers. Materials and Methods: This study was conducted in two large-scale hospitals in which oncology care is given with medical directors (n:70). A questionnaire developed by the researchers asking about demographic characteristics and professional experience, opinions and suggestions of medical directors about providing and integrating palliative care into healthcare was used and responses were analyzed. Results: Potential barriers in providing palliative care (PC) and integrating PC into health systems were perceived as institutional by most of the doctors (97%) and nurses (96%). Social barriers were reported by 54% of doctors and 82% of nurses. Barriers due to interest and knowledge of health professionals about PC were reported by 76% of doctors and 75% of nurses. Among encouragement ideas to provide PC were dealing with staff educational needs (72%), improved working conditions (77%) and establishing a special PC unit (49)%. An independent PC unit was suggested by 27.7% of participants and there was no difference between the hospitals. To overcome the barriers for integration of PC into health systems, providing education for health professionals and patient relatives, raising awareness in society, financial arrangements and providing infrastructure were suggested. The necessity for planning and programming were emphasized. Conclusions: In our study, the opinions and perspectives of hospital managers and clinical directors were similar to current approaches. Managerial needs for treating cancer in efficient cancer centers, increasing the capacity of health professionals to provide care in every stage of cancer, effective education planning and patient care management were emphasized.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1931-1935
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• 2013

Background: This study was undertaken to identify the socio-demographic determinants of quit attempts among smokers and smokeless tobacco users to identify correlates of tobacco cessation behaviour in India Materials and Methods: This was a cross-sectional study for the outcome of quit attempts made by current tobacco users in last 12 months in twelve districts in two states. Simple and multivariable logistic regression analysis was used to obtain the odds ratios (ORs) of socio-demographic variables (age, gender, education, occupation, socio-economic status, community, area, type of family) and tobacco user status (smoker/smokeless). Results: In the combined analysis, a smoker had higher predicted probability of attempting quitting (OR-1.41,CI 1.14-1.90), in comparison to a smokeless tobacco user and a tobacco user in the state of Gujarat was less likely to attempt quitting than a user in Andhra Pradesh (OR-0.60, CI 0.47-0.78). The probability of making a quit attempt was higher among tobacco users who were more educated (OR-1.40, CI 1.04-1.94), having a higher socio-economic status (SES) (OR-2.39, CI 1.54-3.69), and belonging to non-agricultural labourer occupational group (OR-1.90, CI 1.29-2.78). The effects were maintained even after adjusting for all other variables. In disaggregated analysis, findings were similar except in smokeless as a separate group, education level was not significantly associated with quit attempts and with lower odds (OR-0.91, CI 0.58-1.42). Conclusions: This is one of the first studies to provide useful insight into potential determinants for quit attempts of tobacco users in India including smokeless tobacco users, exploring the socio-demographic patterning of correlates of quit attempts.

• Bulletin of the Korean Chemical Society
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• v.26 no.9
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• pp.1359-1365
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• 2005

A series of new chiral [iminophosphoranyl]ferrocenes, {${\eta}^5-C_5H_4-(PPh_2=N-2,6-R_2-C_6H_3)$}Fe{${\eta}^5-C_5H_3-1-PPh^2-2-CH(Me)NMe_2$} (1: R = Me, $^iPr$), {${\eta}^5{-C_5H_4-(PPh_2=N-2,6-R_2}^1-C_6H_3)$}Fe{${\eta}^5-C_5H_3-1-(PPh_2=N-2,6-R_2-C_6H_3)-2-CH(Me)R_2$} (2: $R^1\;=\;Me,\;^iPr;\;R^2\;=\;NMe_2$, OMe), and $({\eta}^5-C_5H_5)Fe${${\eta}^5-C_5H_4-1-PR_2-2-CH(Me)N=PPh_3$} (3:R = Ph, $C_6H_{11}$) have been prepared from the reaction of [1,1'-diphenylphosphino-2-(N,N-dimethylamino) ethyl]ferrocene with arylazides (1 & 2) and the reaction of phosphine dichlorides ($R_3PCl_{2}$) with [1,1'-diphenylphosphino-2-aminoethyl]ferrocene (3), respectively. They form palladium complexes of the type $[Pd(C_3H_5)(L)]BF_4$ (4-6: L = 1-3), where the ligand (L) adopts an ${\eta}^2-N,N\;(2)\;or\;{\eta}^2$-P,N (3) as expected. In the case of 1, a potential terdentate, an ${\eta}^2$-P,N mode is realized with the exclusion of the –=NAr group from the coordination sphere. Complexes 4-6 were employed as catalysts for allylic alkylation of 1,3-diphenylallyl acetate leading to an almost stoichiometric product yield with modest enantiomeric excess (up to 74% ee). Rh(I)-complexes incorporating 1-3 were also prepared in situ for allylic alkylation of cinnamyl acetate as a probe for both regio- and enantioselectivities of the reaction. The reaction exhibited high regiocontrol in favor of a linear achiral isomer regardless of the ligand employed.

• The Journal of Korean Association of Computer Education
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• v.6 no.2
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• pp.81-93
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• 2003

The purpose of the study was to explore the potential of the Social Network Analysis as an analytical tool for scientific investigation of learner-learner, or learner-tutor interaction within an e-Learning environment. Theoretical and methodological implication of the Social Network Analysis had been discussed. Following theoretical analysis, an exploratory empirical study was conducted to test statistical correlation between traditional performance measures such as achievement and team contribution index, and the centrality measure, one of the many quantitative measures the Social Network Analysis provides. Results indicate the centrality measure was correlated with the higher order learning performance and peer-evaluated contribution indices. An interpretation of the results and their implication to instructional design theory and practices were provided along with some suggestions for future research.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2309-2314
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• 2010

Design and syntheses of four red phosphorescent heteroleptic cationic iridium(III) complexes containing two substituted phenylquinoxaline (pqx) or benzo[b]thiophen-2-yl-pyridin (btp) main ligands and one 2,2'-biimidazole (H2biim) ancillary ligand are reported: [$(pqx)_2$Ir(biim)]Cl (1), [$(dmpqx)_2$Ir(biim)]Cl (2), [$(dfpqx)_2$Ir(biim)]Cl (3), [$(btp)_2$Ir(biim)]Cl (4). Complex 1 showed a distorted octahedral geometry around the iridium(III) metal ion with cis metallated carbons and trans nitrogen atoms. The absorption, emission and electrochemical properties were systematically evaluated. The complexes exhibited red phosphorescence in the spectral range of 580 to 620 nm with high quantum efficiencies of 0.58 - 0.78 in both solution and solid-state at room temperature depending on the cyclometalated main ligands. The cyclic voltammetry of the complexes (1-3) showed a metal-centered irreversible oxidation in the range of 1.40 to 1.90 V as well as two quasi reversible reduction waves from -1.15 to -1.45 V attributed to the sequential addition of two electrons to the more electron accepting heterocyclic portion of two distinctive cyclometalated main ligands, whereas complex 4 showed a reversible oxidation potential at 1.24 V and irreversible reduction waves at -1.80 V.

• Journal of Ecology and Environment
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• v.30 no.1
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• pp.81-86
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• 2007

Human activities have enhanced the influx of heavy metals to aquatic ecosystem and hanged the abiotic environment such as the sediments supporting benthic organisms. The levels of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in the benthic gastropod Oxyloma hirasei and the sediments around their habitat were investigated to examine heavy metal levels and the potential of the gastropod as a bioindicator. We detected different levels of heavy metals in the sediments of two wetland areas, Upo and Mokpo, in the relatively well-conserved Upo wetland, Ramsar Convention Area. Oxyloma hirasei had higher concentrations of heavy metals except Cr and Ni in their soft tissues than in their shells (Cd: $2.10{\sim}3.16$, Cu: $19.73{\sim}28.66$, Pb: $0.67{\sim}1.17$, Zn: $216.1{\sim}285.7\;{\mu}g/g$ dry weight in the soft tissues; Cr: $1.19{\sim}2.58$, Ni: $0.47{\sim}1.16\;{\mu}g/g$ dry weight in the shells). Differences in the Cd, Cu, Ni and Pb concentrations in O. hirasei soft tissues reflected differences in heavy metal concentrations in the sediments at the sampling sites. The coefficients of variation for Cd, Cu and Pb were lower than those for other metals in the soft tissues. Levels of Cd in the tissues of O. hirasei were the highest among the metals examined in this study. Therefore, the soft tissue of O. hirasei appears to be a promising bioindicator particularly for Cd.

• Publications of The Korean Astronomical Society
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• v.26 no.3
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• pp.103-114
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• 2011

We have carried out a follow-up study on the students who have participated or are going to participate in either the International Astronomy Olympiad (IAO), the Asia Pacific Astronomy Olympiad (APAO) or the International Olympiad on Astronomy and Astrophysics (IOAA) from 2002 to 2011. The survey questionnaires returned from ten high school students including five who are to participate in 2011 as well as fourteen college students have been analyzed in various aspects of their backgrounds and personal characteristics. In family life, their parents tend to have high educational background along with high expectations for their children. In regard to the academic environment, most students express a general satisfaction in school life, including their relationship with teachers and classmates. In personal characteristics, they describe themselves as inquisitive, perseverant, competitive, creative, self-motivated and goal-oriented, in addition to many other traits. Most students have a strong interest in astronomy which usually begins in middle schools through exposure to astronomy books. On top of it, the astronomy olympiad has provided them with an opportunity to strengthen their self-esteem, problem-solving ability and conviction about scientific careers. Accordingly, the experience in astronomy olympiad has led a considerable number of students to continuously studying in astronomy related fields or otherwise in other science and engineering areas. In conclusion, the astronomy olympiad plays such an important role that it can make a significant contribution to astronomy as well as science in general by having positive impact on the potential career path of its participants.

• Journal of The Korean Association of Information Education
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• v.17 no.3
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• pp.305-316
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• 2013

Despite the potential implications of Facebook use, there is a distinct lack of empirically derived theory for designing learning environment. This may be because Facebook is a social tool and there has been limited opportunity for exploratory research regarding Facebook based learning. Therefore, the purpose of this study is to investigate learning presence factors affecting learning outcomes in Facebook-based collaborative learning. Forty two college students participated in the Facebook-based collaborative learning activity, and the data from thirty nine were used for step-wise multiple regression analysis. In addition focus group interview was conducted to examine learning presence of Facebook-based collaborative learning. The results reported that cognitive presence predicted significantly learning outcomes, however, social and emotional presence did not predict learning outcomes. The implication of this study and future research were discussed in this research.