• Food Science and Preservation
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• v.23 no.1
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• pp.139-143
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• 2016

This study investigated the effect of electron beam (EB) treatment on the microbial reduction of dried laver (Porphyra tenera) and identified EB-resistant bacteria from the treated dried laver. After EB treatments of 4 kGy and 7 kGy, the numbers of total bacteria and EB-resistant bacteria were measured using tryptic soy agar and mannitol salt agar, respectively. The morphological and biochemical characteristics of each isolated EB-resistant bacteria were investigated and these bacteria were identified. Compared to the control ($1.5{\pm}0.2){\times}10^6CFU/g$, the total bacterial number was significantly decreased to ($5.4{\pm}0.5){\times}10^4CFU/g$ and ($1.1{\pm}0.6){\times}10^4CFU/g$ after EB treatments of 4 kGy and 7 kGy, respectively. With a higher EB dosage, the number of red colonies was almost same, whereas the number of yellow colonies was significantly decreased to ($3.3{\pm}1.2){\times}10^3CFU/g$ and 0 CFU/g for 4 kGy and 7 kGy, respectively. All red and yellow colonies were gram-positive cocci, catalase-positive, and resistant to 3% and 5% NaCl media. From the 16S rDNA sequence analysis, yellow and red colonies were identified as either Micrococcus flavus or M. luteus, with 99% similarity for the yellow colonies, and Deinococcus proteolyticus and D. piscis, with 99% and 97% similarity for the red colonies, respectively.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.111-126
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• 1996

Transfer of the isolated nuclei from Lentinus edodes into protoplasts of Pleurotus florida was induced with polyethlene glycol (PEG) and $CaCl_2$. The intergeneric transfer products were classified into nuclear hybrid, heterokaryon or synkaryon, and reconstituted cell. These progenies except nuclear hybrids formed mature fruiting bodies on sawdust rice bran medium. Formation of fruit bodies was influenced by several factors such as light, temperature, nutrition and physic state of the culture media. Most of fruiting body characters were similar to those of P. florida in synkaryon and L. edodes in reconstituted cell, respectively. All these basidiocarps had clamp connections though initial heterokaryon colonies were lacking. Isozyme patterns of intergeneric progenies were quite different from those of parents. DNA polymorphisms of transfer products were also compared by random amplified polymorphic DNAs (RAPD) analysis based on polymerase chain reaction. The RAPD patterns were different from those of donor and recipient. DNA fingerprints ranged in size from 0.25 to 4.0 Kb. On the basis of RAPD, the transfer products were classified into five groups. Two synkaryon were analysed with distribution of progenies and segregation of genetic markers by random spore analyses. The genetic markers were segregated into wild type and riboflavine requiring auxotrophs.

• Journal of Life Science
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• v.25 no.6
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• pp.673-679
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• 2015

The culture conditions needed to maximize the production of laccase from Pholiota highlandensis mycelia were investigated. Among the tested media for laccase production, Coriolus versicolor medium (CVM; 2% dextrose, 0.4% peptone, 0.6% yeast extract, 0.046% KH₂PO₄, 0.1% K₂HPO₄, 0.05% MgSO₄·7H₂O) showed the highest activity for the enzyme. Then, to optimize culture conditions for laccase activity, the influences of various carbon, nitrogen, phosphorus, and inorganic salt sources in CVM were investigated. The optimum culture medium was 2% fructose, 0.4% peptone with 0.6% yeast extract, 0.05% NaH₂PO₄, and 0.05% MgSO₄·7H₂O as carbon, nitrogen, phosphorus, and inorganic salt sources, respectively. Several aromatic compounds in the medium enhanced laccase activity to varying degrees. Guaiacol induced maximum laccase production, yielding 114.1 U/ml laccase activity after cultivation for 11 days at 25℃. The optimum pH and temperature for laccase production were 8.0 and 35℃, respectively. Native polyacrylamide-gel electrophoresis (PAGE) followed by laccase-activity staining with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as the substrate was performed to identify the presence of laccase under the optimum conditions studied. Zymogram analysis of the supernatant culture showed an enzymatic band with a molecular mass of about 90 kDa.

• Journal of Life Science
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• v.23 no.7
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• pp.926-932
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• 2013

Glutamine and serum are essential for cell survival and proliferation in vitro, yet the signaling pathways that sense glutamine and serum levels in endothelial cells remain uninvestigated. In this study, we examined the effects of glutamine deprivation and serum starvation on the fate of endothelial cells using a human umbilical vein endothelial cell (HUVEC) model. Our data indicated that glutamine deprivation and serum starvation trigger a progressive reduction in cell viability through apoptosis induction in HUVECs as determined by DAPI staining and flow cytometry analysis. Although the apoptotic effects were more predominant in the glutamine deprivation condition, both apoptotic actions were associated with an increase in the Bax/Bcl-2 (or Bcl-xL) ratio, down-regulation of the inhibitor of apoptosis protein (IAP) family proteins, activation of caspase activities, and concomitant degradation of poly (ADP-ribose) polymerases. Moreover, down-regulation of the expression of Bid or up-regulation of truncated Bid (tBid) were observed in cells grown under the same conditions, indicating that glutamine deprivation and serum starvation induce the apoptosis of HUVECs through a signaling cascade involving death-receptor-mediated extrinsic pathways, as well as mitochondria-mediated intrinsic caspase pathways. However, apoptosis was not induced in cells grown in glutamine- and serum-free media when compared with cells exposed to glutamine deprivation or serum starvation alone. Taken together, our data indicate that glutamine deprivation and serum starvation suppress cell viability without apoptosis induction in HUVECs.

• Molecules and Cells
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• v.38 no.11
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• pp.950-958
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• 2015

BCS1L gene encodes mitochondrial protein and is a member of conserved AAA protein family. This gene is involved in the incorporation of Rieske FeS and Qcr10p into complex III of respiratory chain. In our previous study, AluYRa2-derived alternative transcript in rhesus monkey genome was identified. However, this transcript has not been reported in human genome. In present study, we conducted evolutionary analysis of AluYRa2-exonized transcript with various primate genomic DNAs and cDNAs from humans, rhesus monkeys, and crabeating monkeys. Remarkably, our results show that AluYRa2 element has only been integrated into genomes of Macaca species. This Macaca lineage-specific integration of AluYRa2 element led to exonization event in the first intron region of BCS1L gene by producing a conserved 3' splice site. Intriguingly, in rhesus and crabeating monkeys, more diverse transcript variants by alternative splicing (AS) events, including exon skipping and different 5' splice sites from humans, were identified. Alignment of amino acid sequences revealed that AluYRa2-exonized transcript has short N-terminal peptides. Therefore, AS events play a major role in the generation of various transcripts and proteins during primate evolution. In particular, lineage-specific integration of Alu elements and species-specific Alu-derived exonization events could be important sources of gene diversification in primates.

• Korean Journal of Microbiology
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• v.36 no.2
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• pp.79-83
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• 2000

Activated sludge samples were collected from a municipal sewage treatment plant and used for enrichment of microbial consortia with aniline as the sole carbon and nitrogen source. Threc aniline-degrading bacteria were obtained lrom microbial consortia and an isolate which has excellent aniline degradability was selected for this study. The isolate was Gram-negative, and identified and designated as Delfha sp. JK-2 on the basis of various physiological and biochemical tests. 10 mM aniline was completely degraded within 24 hours after inoculation of the culture. Ammonium ion was liberated in the medium transiently during the incubation and disappeared when aniline was completely degraded. Addition of glucose as a supplementary source to aniline minimal media showed significant decrease in aniline degradat~on rate for the strain Effective degradation of aniline was achieved by the addition of 0.5% nitrate as a nitrogen source, and resulted in approximately 80% higher aniline degradation compared to the absence of nitrate. Phylogenetic analysis based on 16s [DNA sequence revealed that the strain was closely related to De@ia acidovorans, with 96% overall similarity. The 16s [DNA sequence of JK-2 was also found to be closely related to those of six other clonal types, including Acidovoru, Aquaspirillum. Xylophilus, Variovorm, and Rhodofernr.

• Journal of Korean Library and Information Science Society
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• v.51 no.3
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• pp.103-121
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• 2020

This study aimed to analyze the research trends of school libraries from 1990 to July 2020. To this end, LDA topic modeling analysis was conducted to the domestic article abstracts related to school libraries. The total number of documents is 498 papers published by the four major domestic journals in Library and Information Science. The log-likelihood estimate criterion was used to determine the number of topics for topic modeling. As a result of the study, 27 topics were discovered, then, theory were categorized by eight subject areas: general, institutional system, building/equipment, operation/management, data organization, service, education, and others. The most popular research was library utilization classes (T27) and Information Utilization (T2). More than 20 studies were found in each evaluation index development (T13), school librarian placement (T24), learning information media utilization (T3), community public library (T7), library cooperation (T9), library use (T17), library research (T11), reading education (T4), collection development (T5), and education effects/teaching methods (T18).

• The Korean Journal of Pharmacology
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• v.29 no.1
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• pp.73-83
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• 1993

In order to examine the effect of ${\beta}-estradiol$ on the cell growth, using a primary rabbit kidney poximal tubule cell culture system. We investigated the effect of ${\beta}-estradiol$ on alpha 1 (IV) collagen and ${\beta}-actin$ mRNA levels from primary rabbit kidney cell cultures, and also the effects of 3 growth factors and ${\beta}-estradiol$ supplementation on the growth of primary rabbit kidney proximal tubule cells in the serum-free medium. 1 nM of ${\beta}-estradiol$ showed a sizable potentiation effect on the growth of the proximal tubule cell in serum-free medium, but higher concentration (> 10 nM) of estradiol indeed inhibited the growth. In the absence of hydrocortisone as a growth supplement in serum-free medium, ${\beta}-estradiol$ caused to potentiate the growth of the cell. In the presence of hydrocortisone, ${\beta}-estradiol$ also potentiated the growth of the proximal tubule cells. According to the Northern analysis, ${\beta}-estradiol$ increased the level of ${\beta}-actin$ mRNA, although mRNA level of the alpha I(IV) collagen was not changed significantly.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.289-304
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• 2018

The fandom phenomenon of political emotion originated from ideological conflicts between the conservative and the progressive amplifies social conflicts in South Korea in interpreting and accepting films as culture media. The purpose of this paper is to examine why the structure of political consciousness in South Korea is fandomized, what is the acceptance of cinema at the center of the controversy of political ideology, and what is the desirable attitude of film reception. I conducted a discourse analysis that closely examined the debates and articles on the internet regarding ,(2013) and ,(2014) which were controversial in terms of conservatism and progressivism. As a result, First, while Korean society has not constituted a consensus on modern and contemporary history, it has easily led the acceptance of cinema to the controversy surrounding the political ideology. Second, the failure of constructing consensual memories of modern and contemporary history has made the conservative and the progressive not acknowledge the other's achievements. Third, film interpretation and meaning production are ultimately the roles of the audience, and on interpretation, diversity should be respected but conformity would be rejected. Film acceptance and interpretation should focus on rational awareness of social reality and would reflect on the social ideal objectively.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.10
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• pp.1038-1045
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• 2006

A series of experiments was conducted to test the compatibilities of two different techniques to determine elemental concentrations by INAA and ICP-MS based on both the NIST SRM 2783(air particulate on filter media) and the field samples for PM10. For NIST SRM the results of INAA were more accurate and precise for all target elements than those of ICP-MS. The comparative data set for PM10 samples collected in an industrial complex area showed that mean of concentration ratio, derived for the two different methods such as C(INNA/ICP-MS), were distinguished from each other: (1) Ba, Cu, K Mg, Na, and Sb: $0.9{\sim}1.1$; (2) Al, Co, Fe, and Mn: $0.8{\sim}1.2$; and (3) Se, Ti, and Zn: >1.3. When the results obtained from both methods were evaluated in terms of regression analysis, paired t-test, and Wilcoxon signed-rank test, the results of many elements determined from PM10 samples(such as Al, Ba, Co, Cu, Fe, K, Mn, Nd, and Sb) exhibited a fairly good agreement between the two methods, despite a wide range of variation.