• Korean Journal of Microbiology
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• v.52 no.4
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• pp.455-462
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• 2016

Pseudomonas aeruginosa P-5 is an unusual organism capable of synthesizing polyhydroxyalkanoates (PHAs) consisting of 3-hydroxyvalerate (3HV) and medium-chain-length (MCL) 3-hydroxyalkanoate (3HA) monomer units when C-odd alkanoic acids are fed as the sole carbon source. Evaluation of the substrate chain-length specificity of two P. aeruginosa P-5 PHA synthases ($PhaC1_{P-5}$ and $PhaC2_{P-5}$) by heterologous expression of $PhaC1_{P-5}$ and $PhaC2_{P-5}$ genes in Pseudomonas putida GPp104 revealed that $PhaC2_{P-5}$ incorporates both 3HV and MCL 3HAs into PHA, whereas $PhaC1_{P-5}$ favors only MCL 3HAs for polymerization. In order to obtain $PhaC2_{P-5}$ mutants with altered substrate specificity, site-specific mutagenesis for $PhaC2_{P-5}$ was conducted. Amino acid substitutions of $PhaC2_{P-5}$ at two positions (Ser326Thr and Gln482Lys) were very effective for synthesizing copolymers with a higher 3HV fraction. When recombinant P. putida GPp104 harboring double mutated $phaC2_{P-5}$ gene ($phaC2_{P-5}QKST$) was grown on nonanoic acid, 2.5-fold increase of copolymer content with 3.8-fold increase of 3HV fraction was observed. The $phaC2_{P-5}QKST$-containing Ralstonia eutropha PHB-4 supplemented with valeric acid also produced copolymers consisting of 3HV and 3-hydroxyheptanoate with a high 3HV fraction. These results suggest that recombinants containing $phaC2_{P-5}QKST$ could be useful for production of new PHA copolymers with improved material properties.

• Journal of Life Science
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• v.19 no.9
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• pp.1314-1320
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• 2009

Histone deacetylase inhibitor (HDACI) is a new promising candidate as an antineoplastic agent for the treatment of solid and hematologic malignancies. In order to evaluate cell death and to elucidate the related mechanism(s) in NSCLC cells after HDACI, sodium butyrate (SB), a representative HDACI, was used to treat H460 cells for 48 hrs. SB exposure resulted in a significant reduction of cell viability at concentrations below 7.5 mM, and about 50% of cell death occurred at 20 mM. The types of cell death induced by SB were both apoptosis and necrosis, evaluated by Annexin-V staining combined with propidium iodide. SB treatment significantly evoked G2/M cell cycle arrest and subsequently induced cell death with caspase-dependent manner. While ERK protein content was not altered after SB, phosphorylated forms of ERK were markedly reduced. Taken together, SB is significantly able to induce cell death in NSCLC cell line H460, and it is suggested that the reduction of ERK phosphorylation might be closely involved in the cancer cell death mechanism initiated by HDACI.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.625-632
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• 2008

Rye-wheat mixed bread samples made with substitutions of 20, 40, 60 and 80% sourdough, and control made with the addition of naturally fermented raisin extract, were examined for quality characteristics such as pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, water activity, color, texture, external and internal surface appearance, and sensory qualities, in order to determine the optimal ratio of sourdough in the formulation. As the incubation time of sourdough increased, pH decreased, while total titratable acidity increased. The pH of rye-wheat mixed doughs decreased with increasing sourdough content, but total titratable acidity increased. The rye-wheat mixed breads prepared with substitutions of sourdough had higher pH and lower total titratable acidity than the control group. Fermentation power of dough expansion of rye-wheat mixed doughs increased with increasing incubation time. Specific volume was maximum on the 20% substitution sourdough. Baking loss was inferior with the 80% substitution sourdough. Water activity and lightness was minimum on the control group. The higher amounts of sourdough showed the higher tendency of lightness, redness and yellowness. In the texture characteristics, hardness, gumminess, and chewiness was minimum on the control group and tended to increase with higher substitution of sourdough. Substitution of sourdough showed decrease adhesiveness. Fracturability, cohesiveness, and resilience of all rye-wheat mixed breads were not significantly different. Springiness was maximum on the 20% substitution sourdough and minimum on the 40%. A side of loaf of rye-wheat mixed breads, except for 20%, had a poor break and shred. In sensory evaluation, as substitution amount of sourdough increased, the scores of color and consistency of crumb, uniformity of crumb pore, gumminess, and overall acceptability decreased; while the density of crumb pore, springiness of crumb, aroma of rye flour, sourness, and bitterness showed the reverse effect; the 20, 40, and 60% sourdough samples obtained fairly good scores. In conclusion, these results indicated that $20{\sim}60%$ of sourdough could be very useful as a substitute for baker's yeast in developing rye-wheat mixed bread.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.97-104
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• 2018

The larva of the white-spotted flower chafer, Protaetia brevitarsis seulensis (Coleoptera: Cetoniidae), is known to have important medicinal properties, such as anti-cancer activity. However, the consumer market for the larvae is depressed because of its high production cost which needs to be reduced. This study was carried out to evaluate two spent mushroom substrates as food source for chafer larvae to improve the productivity and reduce production cost. The larvae were fed with spent substrates of king oyster mushroom (Pleurotus eryngii) (P-SMS) and shiitake mushroom (Lentinula edodes) (L-SMS), with a control of fermented oak sawdust. Effects of the diets on the development of P. brevitarsis seulensis and contents of minor nutrient components in the larvae produced were examined. In the P-SMS diet, the larval rearing period was shorter at 16.2 days, while the rate of larval weight gain and the cocoon weight were higher at 156.3% and 4.1 g, respectively, than that in the L-SMS diet. The pupation rate was 100% and the adult emergence was higher at 93.3% in the P-SMS diet than in the L-SMS diet with no difference to the control diet. In the P-SMS diet, the total nitrogen content during rearing was higher at 10.28% and the minor nutrient component, particularly Fe (145.8 mg/kg), was higher than that in other diets. The oviposition preference of adults showed no significant difference among the diets. Economic analysis showed that P-SMS costs approximately 667,960 Won less per 100 kg of larvae produced, compared to that of the control diet.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.469-479
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• 2001

This study investigated the trends in the number of applicants and mean score and applicants’ responses on the test items of Earth Science in the College Scholastic Ability Test (CSAT) implemented for 3 years (1999-2001). The percentage of applicants of science track were 43.14% in 1995, but reduced through 29.5% in 2001 to 26.92% in 2002 CSAT For elective subject, about 22% of science track students applied to Earth Science II which ranked third to Biology II and Chemistry II. In 1999, test items were developed to have the expected difficulty 40 ${\sim}$ 59% (6 items) to 60 ${\sim}$ 79% (10 items). But in 2001 every 16 items were developed to have difficulty 60 ${\sim}$ 79%, which was caused by the policy of so called ‘easy CSAT’. Thus the mean score of ‘Earth Science II’ was increased from 50.26 in 1999 through 64.47 in 2000, to 67.58 in 2001. Applicants were generally very good at solving test items focusing on process skills only and familar items but poor at solving test items related to the motion of the earth and planets and sea wave, especially items calling two or more concepts. Thus special measures to cope with the decrease in applicants of science track should be provided. And it is recommended to develop test items with wider range of difficulty and to reduce test items calling process skills only. And special consideration should be given to teaching the content area with poor achievement and high actual difficulty compared to the expected.

• Journal of the Korean earth science society
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• v.18 no.6
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• pp.453-463
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• 1997

The contents of high school 'Common science' textbooks was analyzed qualitatively and quantitatively. Seven common science textbooks were selected and its contents, structure, inquiry, activities, appendix and its characteristics were investigated, and analyzed using the Goal Clusters of Project Synthesis and Romey's indices of text evaluation were calculated. The contents of each unit are not much different among textbooks because they are written according to the curriculum ordinance and textbook guidelines of the Ministry of Education. The textbooks was consist of $471{\sim}519$ pages. It was distribute similarly among the chapter of 'materials', 'forces', lives' and 'earth'. The chapter of 'energy' and 'environment' was treat significantly. The contents and structure of common science is a mere physical consolidation. I make an alternative plan that a topic form. Inquiry activities used in the textbooks are 11 type, however most of that is interpretation of data, experiment, survey and discussion. Ninety six percents of the experiment, belong to the 1st level, four percents of that belong to the 2nd level of the Schwab's inquiry level and there are no activities of the 3rd level. Little attention is given to Goal Cluster I, II, IV in the common science textbooks currently employed. Its content should be broadened to include all Goal Clusters of Project Synthesis. Homey's indices representing the degrees of student involvement. are $0.57{\sim}1.14$ for sentence analysis, $0.60{\sim}1.67$ for figure and diagram analysis, $0.67{\sim}1.50$ for analysis of questions at chapter ends, respectively, student activity per page investigated being $0.6{\sim}0.9$. But chapter summaries cease to repeats the conclusions of the chapter also it be rather formally and inattentively written.

• Culinary science and hospitality research
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• v.22 no.2
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• pp.115-124
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• 2016

The purpose of this paper is to verify improvement of the basic quality of food resources and make the pork legs as the more advanced food products after taking special processing steps with the mixture of traditional medical herbs and hot water extracted coffee meal. The pH level of the pettitoes(Jokbal) showed the highest rate among the control group but it showed no statistical differences in the moisture content between the control and the pettitoes(Jokbal) processed with coffee waste extract as an additional component. In addition, the levels of crude fat and crude ash showed slight increases as the addition of the amount increase. In case of the proteins, however, tendency of slight was decreased but it was not significantly difference as the amount increases. The sodium rate in the pettitoes(Jokbal) was higher in the additional group than in the control group. Texture analysis showed a tendency of wide decrease in the hardness and chewiness depending on amount of the added coffee waste extract. On the other hand, as for the cohesiveness and springiness, there was no significant difference with the control group. In case of the lightness value, as the amount of added coffee waste extract is increased from 10% to 20% and 30%, the 'L' value was reduced significantly compared to that of the control. And the 'a' value was not significantly different compared to the coffee waste extract foil impregnated furniture control. But the 'b' values were significantly increased in accordance with the result of increasing the amount of control is at the lowest level. The result may come from the influence of coffee waste extract, which affects the color of the pettitoes(Jokbal). According to the sensory evaluation, the pork part with 10% of coffee waste extract showed the highest score in looking, chewiness, smell and preference, resulting in the improvement in quality of the pettitoes(Jokbal).

• Culinary science and hospitality research
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• v.22 no.8
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• pp.27-38
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• 2016

This study examined the nutrient components and physicochemical properties of Acer termentosum Maxim. leaf as a natural health food source. To accomplish this purpose, the general and antioxidative contents of Acer termentosum Maxim leaf were measured. Total contents of carbohydrates, crude protein, crude lipid, and ash were 53.6%, 24.3%, 3.5%, and 3.5%, respectively. Caloric content of Acer termentosum Maxim was 246.5 kcal, while total dietary fiber was 46.7%. Regarding mineral contents, K was the most abundant mineral, followed by Ca, Mg, and P. Therefore, Acer termentosum Maxim is an alkali material. Total phenol contents of the 70% ethanolic extracts of Acer termentosum Maxim was $116.35{\pm}1.4mg\;GAE/g$. Total flavonoid contents of the 70% ethanolic extracts were $20.3{\pm}1.23mg\;RE/g$. The antioxidative activities of Acer termentosum Maxim. were significantly increased in a dose dependent manner on DPPH(1,1-Diphenyl-2-picrylhydrazyl) radical scavenging, ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) radical scavenging, FRAP (ferric reducing antioxidant power) activity, reducing power. It is expected that follow up study of Acer termentosum Maxim through developing processed food and evaluation of their functional properties would provide useful information as a source of functional foods.

• The Korean Journal of Elementary Counseling
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• v.8 no.1
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• pp.33-50
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• 2009

The purpose of this study was to develop a PBL-based career education program and to examine its effectiveness on school children's career maturity. It's specifically meant to prepare a career education program to assist students to get an accurate grip on their aptitude, interest and personality and explore various sorts of occupations in the course of solving authentic and contextual career-related problems. After children's developmental characteristics and needs were analyzed, task analysis was implemented, and the objectives were defined. And then the core of the program, PBL problems were developed, and the validity of the problems were verified Evaluation plans and tools were prepared to assess children's problem-solving process and presentation, and an online learning space was designed. The program that consisted of 10-minute 21 sessions was provided to fifth-grade elementary schoolers for eight weeks. The findings of the study were as follows: The experimental group that participated in the PBL-based career education program showed a more significant improvement than the control group that didn't in career attitude and three career attitude subfactors involving planness, disposition and compromise. And the former made a more significant progress than the latter in career ability and its subfactors including vocational comprehension, self-understanding and decision-making skills as well. As a result of making a content analysis to make up for the survey, the students reported that they were able to get an objective understanding of themselves and acquire diverse and profound knowledge on work and the business world in the middle of solving the given PBL problems related to different areas in group and giving a presentation. In conclusion, a PBL based career education program developed by this researcher encouraged the students to have an objective self-understanding, to have a dynamic interactive discussion with their group members. Therefore the program had a positive impact on boosting the career attitude and career ability of the elementary schoolers. The findings suggested that in the field of elementary career education, autonomous learning attitude and subjecthood are the crucial factors to stimulate school children to explore and create their own future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1195-1201
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• 2009

Dietary effects of Agaricus bisporus powder (ABP) on the quality characteristic of eggs from hens (Hy-Line) were investigated. Experimental groups (100 hens/group) were divided into normal control group (Control), 0.3% ABP supplemented diet group (M-0.3) and 0.6% ABP supplemented diet group (M-0.6), then fed for 12 weeks. There were no significant differences in shell thickness, while Haugh unit in M-0.3 and M-0.6 groups were 18.3$\sim$27.6% higher than that of control groups. Color $L^*$ and $b^*$ values of egg albumen and yolk in the M-03 and M-0.6 groups were lower whereas $a^*$ values were higher than those of NC group. In the yolk of M-03 and M-0.6 groups compared with control groups, the levels of total phospholipids and HDL-cholesterol were 4.5$\sim$13.9% and 86.1$\sim$87.0% higher, respectively, while the levels of total cholesterol, triglyceride and LDL-cholesterol were 29.4$\sim$31.9%, 51.9$\sim$52.4% and 49.1$\sim$53.5% lower than those of control groups, respectively. There were no significant differences in fatty acids. In the result of sensory evaluation, gory odor of raw eggs in the M-03 and M-0.6 groups was slightly lower compared with control groups. These results suggest that the feed containing mushroom of Agaricus bisporus can be used to reduce the egg yolk cholesterol content and gory odor from raw egg, and also to increase the phospholipids as a functional feed. Further studies on the mechanism are required.