• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.266-279
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• 2021

This study applied the e-PBL (e-Project-based learning) method for "Urban Forest Management" courses in the Department of Forest Science at S University to progress in university forest education. e-PBL effectively motivates self-directed learning, problem-solving, communication skills, and learners' responsibility by enabling them to choose, design, and perform their projects. Due to the COVID-19 pandemic in 2020, learners were encouraged to use online media to carry out projects and submit presentations for the campus forest. Learners' educational effects were subsequently investigated through a five-point Likert scale. This study discovered a positive effect on learners' motivation and interest (4.17) through e-PBL. Learners responded that e-PBL also helped their understanding regarding the subject (4.17). In addition, this study provided evidence that the e-PBL method was helpful in problem-solving (4.25), communication (4.33), and decision-making skills (4.21). According to learners' responses, there are positive indications that learners were satisfied with e-PBL. Learners responded that interactions and communications with team members could improve their understanding of the subject. Hence, there is scope for improving an efficient and successful e-PBL model suitable for university forest education by providing more efficient instructional time management, e-PBL method guidelines, and institutional support.

• Archives of Pharmacal Research
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• v.17 no.3
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• pp.194-198
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• 1994

The antitumor effects of the 2E4 and anti--Tac, monoclonal antibodies directed to Il-2 receptor (IL-2R) conjugated with .alpha.-particle emitting radionuclide bismuth-212., were compared. The $^{212}Bi-2E4$ demonstratedspecific cytotocicity to EL4J3, 4, a I$L-2R^+$ cell line, than to EL4J, a $IL-2R^-$ cell line in thymidine incorporation assy. TEX>$^{212}Bi-2E4$ exerted the maximal antitumor effect in that % T/C in C57BL/6 mice implanted with EL4J3.4 ascitic tumor was 331% at the concentration of $50{\;}{\mu}Ci$, while that of $^{212}Bi-anti-Tac$ was 258% at $100{\;}{\mu}Ci$.

• Nuclear Engineering and Technology
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• v.55 no.12
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• pp.4543-4553
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• 2023

The dose from a possible accident at a microwave-based spent resin mixture treatment facility that was to be installed and operated at the Wolsong nuclear power plant was analyzed to evaluate the radiological safety prior to its installation and operation. The dose to which workers and nearby residents are likely to be exposed was calculated based on the atmospheric dispersion and deposition factors using the XOQDOQ code. The highest atmospheric dispersion factors were 1.349E-05 s/m³ (workers) and 1.534E-06 s/m³ (residents). The highest doses due to emissions from the mock-up tank before operation were 1.91E-06 mSv (workers) and 1.78E-07 mSv (residents). Even after 3 h of operation, emissions from the mock-up tank had the greatest impact ranging from 4.63E-08 to 1.24E-06 mSv (workers) and 2.74E-10 to 1.16E-07 mSv (residents), respectively. The doses were 7.09E-09-4.55E-07 mSv and 4.18E-11-4.25E-08 mSv at 4-5 h of operation, and the maximum doses after operation reached 5.69E-07 mSv and 5.31E-08 mSv for the workers and residents, respectively. Even at the exclusion area boundary (EAB), 4.76E-08-9.51E-07 mSv (annual dose:9.52E-05–1.90E-03 mSv/y) was below the dose limit of the EAB, and the safety of the facility installation inside the NPP was confirmed.

• Korean Journal of Community Nutrition
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• v.13 no.5
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• pp.713-722
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• 2008

The purpose of this study was to investigate the association among nutrient intakes and health-related lifestyles with cardiovascular disease risk assessed by blood lipid profile according to Apolipoprotein E genotypes. Middle-aged industrial male workers who had completed their annual medical examination were recruited and data of 675 subjects who finished the nutrient survey were used in the analysis. Anthropometric parameters, dietary assessment (FFQ), health-related lifestyles and blood profiles were used for statistical analyses. Apo E genotype groups were classified into the following three genotypes: Apo E2 group (including E2/E2, E2/E3, E2/E4), Apo E3 group (including E3/E3), Apo E4 group (including E3/E4, E4/E4). The frequency of Apo E2, E3, and E4 allele were 13.3%, 75.0% and 11.7% respectively. There were no significant differences in the anthropometric parameters depending on different Apo E genotypes. Also, no significant differences in the nutrient intakes were found according to the genotype groups. The nutrient intakes of all subjects were similar to or higher than the level of KDRIs (Dietary Reference Intakes For Koreans) except for intakes of calcium (67.44% of KDRIs), vitamin A (73.83% of KDRIs) and vitamin $B_2$ (78.02% of KDRIs). Also, there were no significant differences of health-related lifestyles according to Apo E genotype groups. As for the lipid profiles, Apo E4 group had significantly higher total and LDL-cholesterol concentrations than the Apo E2 group (p < 0.05). We confirmed that plasma total and LDL-cholesterol concentrations were greatly influenced by Apo E genotypes. However, nutrient intakes and health-related lifestyles were not associated with Apo E genotypes.

• Honam Mathematical Journal
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• v.40 no.1
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• pp.47-59
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• 2018

We define the $e^{\alpha}_1e^{\alpha}_3$-isotropic Smarandache curves of type-1 and type-2, the $e^{\alpha}_1e^{\alpha}_2e^{\alpha}_3$-isotropic Smarandache curve, and the $e^{\alpha}_1e^{\alpha}_2e^{\alpha}_4$-isotropic Smarandache curves of type-1 and type-2. Then we examine these kinds of isotropic Smarandache curve according to Cartan frame in the complex 4-space $\mathbb{C}^4$ and give some differential geometric properties of these Samarandache curves.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.575-579
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• 1991

Reaction of 6${\beta}$-bromopenicillanic acid(4a) with p-nitrobenzylbromide, 3-bromophthalide, chloromethylpivalate and 1-chlorodiethylcarbonate afforded 6${\beta}$-bromopenicillanates(4b~4e). New ${\beta}$-lactam compound, 6-(carboxymethylthio)penicillanic acid(5a) and the other esters(5b~5e) were prepared by nucleophilic substitution reaction of 6${\beta}$-bromopenicillanic acid(4a) and the other esters(4b~4e) with thioglycolic acid.

• Nutritional Sciences
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• v.9 no.2
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• pp.82-91
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• 2006

This study was performed to investigate the effect of normal diet with or without naringin supplement on the lipid and antioxidant metabolism in ethanol-treated rats for a short tenn. Male Sprague-Dawley rats were divided into three groups (n=10), which were assigned to one of three dietary categories : $E_8$ : ethanol diet for 8 wks, $E_4N_4$ : ethanol diet for the first 4 wks and normal diet for the last 4 wks, $E_4Nna_4$ : ethanol diet for the first 4 wks and normal diet with naringin supplement for the last 4 wks. Plasma total cholesterol concentrations were significantly higher in ethanol fed rats for 8 weeks. The HDL-C/total-C ratios of the $E_4N_4$ and the $E_4Nna_4$ groups were significantly higher than that of the $E_8$ group, while the atherogenic index was lower in the $E_4N_4$ and the $E_4Nna_4$ groups than in the $E_8$ group. The $E_4N_4$ and $E_4Nna_4$ diets significantly lowered both the hepatic cholesterol and triglyceride levels compared to the $E_8$ group. Accumulation of hepatic lipid droplets was observed to be the highest in the $E_8$ group. In the current study, the naringin supplement to normal diet significantly lowered both the hepatic HMG-CoA reductase and ACAT activities in ethanol pre-treated rats for 4 weeks. Antioxidant enzyme activities were also upregulated when ethanol feeding was ceased. Naringin supplement given for 4 weeks after ethanol cessation resulted in a significant decrease in the plasma cholesterol and hepatic lipids and plasma TBARS as well as the hepatic HMG-CoA reductase and ACAT activities compared to the rats given ethanol diet for the entire 8 weeks. Replacement of normal diet following a short tenn ethanol feeding was effective for the recovery of ethanol-induced fatty liver and for normalizing plasma and hepatic lipid profiles and antioxidant enzyme activities, regardless of an additional phytochemical supplement, naringin. The effect of naringin could seemingly be more evident if its supplementation period had been extended longer than 4 weeks after ethanol cessation.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.251-255
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• 2011

A new and highly stereoselective synthesis of (E)-4'-amino-3,4,5-trimethoxystilbene was achieved by using 3,4,5-trimethoxybenzaldehyde and p-nitrotoluene as starting materials through condensation under solvent-free condition and followed by the reducing of nitro group with the system of $NH_2NH_2/FeCl_3$/C in ethanol. The crystal structure of (E)-4'-amino-3,4,5-trimethoxystilbene was also determined by X-ray diffraction analysis.

• Korean Journal of Biological Psychiatry
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• v.7 no.2
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• pp.152-158
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• 2000

Background : No association between schizophrenia and dopamine D4 receptor polymorphisms have been reported. Despite these results, it is premature to exclude the association. It has been suggested that the susceptibility to develop schizophrenia could result from variation at a number loci which may interact or coact with each other. Therefore, we investigated a possible association of combinations of exon III 48bp polymorphism[D4E3] and exon I 12bp polymorphism of the DRD4 gene [D4E1] with schizophrenia. Methods : 207 unrelated Korean schizophrenic patients and 191 healthy controls were recruited. DRD4 genotype was established using the polymerase chain reaction. Statistical analysis consisted of ${\chi}^2$ tests for Hardy-Weinberg proportions and genotypic and allelic frequencies in the patients and control groups. Results : There were no statistically significant differences in the each polymorphisms between schizophrenics and controls. And all genotype frequencies were within Hardy-Weinberg expectations. When the combinations of the polymorphism in schizophrenia and controls were compared, however, there were significant differences at $A1A2^*2/4$ in the distributions of the combinations of D4E1 and D4E3(p<0.01). Conclusions : These findings suggest that the certain combination of D4E1 and D4E3($A1A2^*2/4$) has the protective role to a susceptibility for schizophrenia.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.126-130
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• 2013

The major aim of this study was to investigate the distribution of genes that encode multidrug efflux pumps in Enterococci spp. isolates from bovine milk samples and antibiotic resistance patterns of these strains. Of the 245 isolates, 44.1% showed ampicillin resistance, 79.2% showed erythromycin resistance, 76.3% showed tetracycline resistance and 36.3% showed chloramphenicol resistance. In case of vancomycin and ciprofloxacin, all of the isolates were susceptible to these antibiotics. Of the 245 enterococcal isolates, 82.1% have MFS type eme(A) gene, 72.7% have ABC type efr(A) gene, 77.1% have ABC type efr(B) gene, and 71.8% have ABC type lsa gene. In case of Enterococcus faecalis, the original strain for these genes, 92.5% have eme(A), 87.4% have efr(A), 88.4% have efr(B), and 88.4% have lsa. Interestingly, in case of different species of Enterococci, eme(A) was also detected in four strains of E. faecium, seven strains of E. avium, four strains of E. durans and two strains of E. raffinosus. efr(A) was also detected in two strains of E. faecium and two strains of E. durans and efr(B) was also detected in four strains of E. faecium, five strains of E. avium and four strains of E. durans. This means the possibility of co-transfer of resistance genes between Enterococci species in natural environment. These results are the first report describing the presence of same multidrug efflux pumps in different species of Enterococci in Korea.