• Journal of Ecology and Environment
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• v.32 no.4
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• pp.237-247
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• 2009

This study was conducted to determine the carbon (C) contents in different mixed stands of P. dens if/ora and deciduous oak species in Gwangneung, central Korea. Five mixed stands with different ratios of P. densiflora and deciduous oak species were chosen based on the basal area of all trees ${\geq}\;5cm$ DBH: pure P. densiflora (P100D0), 70% P. densiflora + 30% deciduous oak species (P70D30), 44% P. densiflora + 56% deciduous oak species (P50D50), 37% P. densiflora + 63% deciduous oak species (P40D60), and 10% P. densiflora + 90% deciduous oak species (P10D90). Total C contents in the overstory (aboveground and belowground) vegetation were higher in the mixed stands (P70D30, P50D50, P40D60) than in the pure stands (P100D0, P10D90). Moreover, except for P40D60, C contents of forest floor (litter and coarse woody debris) were larger in the mixed stands (P70D30, P50D50) than in the pure stands. However, total soil C contents up to 30cm depth were highest in the pure deciduous oak stand than in the pure P. densiflora stand and mixed stands. Total ecosystem C contents (Mg/ha) were 163.3 for P100D0, 152.3 for P70D30, 188.8 for P50D50, 160.2 for P40D60, and 150.4 for P10D90, respectively. These differences in total ecosystem C contents among the different mixed stands for P. densiflora and deciduous oak species within the study stands were attributed by the differences in vegetation development and forest management practices. Among the five study stands, the total ecosystem C contents were maximized in the 1:1 mixed ratio of P. densiflora and deciduous oak species (P50D50).

• Journal of Life Science
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• v.28 no.4
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• pp.488-495
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• 2018

The p53 gene plays a critical role in the transcriptional regulation of cellular response to stress, DNA damage, hypoxia, and tumor development. Keeping in mind the recently discovered manifold physiological functions of p53, its involvement in the regulation of cancer is not surprising. In about 50% of all human cancers, inactivation of p53's protein function occurs either through mutations in the gene itself or defects in the mechanisms that activate it. This disorder plays a crucial role in tumor evolution by allowing the evasion of a p53-dependent response. Many recent studies have focused on directly targeting p53 mutants by identifying selective, small molecular compounds to deplete them or to restore their tumor-suppressive function. These small molecules should effectively regulate various interactions while maintaining good drug-like properties. Among them, the discovery of the key p53-negative regulator, MDM2, has led to the design of new small molecule inhibitors that block the interaction between p53 and MDM2. Some of these small molecule compounds have now moved from proof-of-concept studies into clinical trials, with prospects for further, more personalized anti-carcinogenic medicines. Here, we review the structural and functional consequences of wild type and mutant p53 as well as the development of therapeutic agents that directly target this gene, and compounds that inhibit the interaction between it and MDM2.

• Korean Journal of Ichthyology
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• v.10 no.1
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• pp.32-39
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• 1998

Structures of jaw bones, gill rakers and pharyngeal bones of the three Pomadasys species collected from Arafura sea of Indonesia in May 1996 were described and illustrated to compare between species. The percentage of ascending process of premaxillary to head length was 21.6~23.3% in Pomadasys kaakan, 25.4~27.8% in P. maculatus and 15.3~21.0% in P. argyreus. The percentage of ascending process of premaxillary to premaxillary was 54.7~72.8% in P. argyreus, 107.8~114.9% in P. kaakan and 126.7~136.7% in P. maclllatlls. The ascending process of premaxillary of P. argyreus showed a tendency to increase as fish grow. Each jaw in all three grunters had a row of conical teeth exteriorly, but 1 to 5 rows of niddle like teeth interiorly. Among the three species examined, P. maculatus showed the most developed teeth. Pharyngeal bone, appeared to be stronger than jaw teeth, contained dense needle like teeth in P. argyreus, where as that in P. kaakan and P. maculatus had long and slender teeth exteriorly but thicker interiorly. Gill rakers of P. kaakan and P. maculatus are short, but those of P. argyreus are long.

• Horticultural Science & Technology
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• v.35 no.3
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• pp.289-299
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• 2017

The objective of this study was to determine the effect of replacing perlite (PL) with pellets processed with poultry feather fiber as an inert material to prepare growing medium. The growth and flowering of Salvia splendens 'Vista Red' grown in individual growing medium $Biosangto^{(R)}$, peat moss (PM), PL, and two pellets (P45-1 and P45-2) were evaluated. Peat moss was mixed with PL, P45-1, or P45-2 at various ratios (1:0 to 1:3 or 3:1 by volume) to investigate the feasibility of replacing PL with pellets. Nutrient composition of the growing medium and leaf tissues was analyzed. The number of florets, inflorescence length, plant height, and fresh weight of plants grown in media containing P45-1 or P45-2 were reduced compared to those grown in individual growing medium PM or PL. As the mixing ratio of P45-1 or P45-2 to PM was higher, the growth of salvia, such as inflorescence length, plant height, number of leaves, and fresh weight was inhibited. Our results indicate that mixing three parts PM with one part of P45-1 (PM/P45-1/3:1) or P45-2 (PM/P45-2/3:1) accelerated flowering and increased the number of florets and leaves compared to other mixing ratios of PM and pellets media. The concentrations of phosphorus (P), calcium (Ca), boron (B), iron (Fe), and copper (Cu) in individual growing medium PL, P45-1, and P45-2 were significantly lower than those in PM. The concentration of N was the highest in leaves of plants grown in P45-1 or P45-2 amended media, and the concentrations of P, Ca, and zinc (Zn) in leaves were lower in individual growing medium P45-1 or P45-2 than in PM and PL. The pH of PM/P45-1/3:1 or PM/P45-2/3:1 media was maintained at optimal level (5.8-5.9) and the concentrations of macro- and micro-elements in the media and leaves were considered to be optimal levels. Therefore, mixing three parts PM with one part P45-1(PM:P45-1/3:1) or P45-2 (PM:P45-2/3:1) is recommended for improved growth and flowering in salvia. This suggests that P45-1 or P45-2 can replace PL as an inert material to prepare growing medium.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.2
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• pp.128-135
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• 2007

This study was designed to investigate the correlation between the expression rate of p53 and p21 proteins by immunohistochemical staining and tumor prognostic factors including the tumor size, histological differentiation and Dukes' stage of tumor prognostic factors in colon cancer, and to acquire necessary data for the presumption of diagnosis, treatment and prognosis of colon cancer patients. From January 2000 to January 2003 at Hanyang University Guri Hospital, the paraffin blocks of 35 patients diagnosed with colon cancer whose pathologic reports were possible to review were selected. Harris hematoxylin & eosin (H&E) staining and immunohistochemical staining by ABC (Avidin Biotin Conjugate) method were performed. The histological differentiation grade and stage were classified according to the classification of the World Health Organization (WHO) and modified Dukes's stage from H&E staining. The expression rate of p53 and p21 proteins were analyzed by immunohistochemical staining. The results was analyzed statistically by SPSS (Windows version 8.0). As a result, the expression rate of p53 protein was 11.4% (4 cases) in clear differentiation, 48.6% (17 cases) in moderate differentiation, and 17.1% (6 cases) in poor differentiation. In other words, the poorer the differentiation, the higher the expression rate of p53 protein (p<0.05). The expression rate of p21 was 17.1% (6 cases) in clear differentiation, 40.0%(14 cases) in moderate differentiation, and 8.6% (3 cases) in poor differentiation, According to the progression of histological malignant degeneration, the expression rate of p21 protein decreased distinctively (p<0.05). However, the correlation between the two above mentioned proteins and the tumor-size and Dukes' stage was not of statistical significance. In the comparison of the expression rate of p53 protein with that of p21 protein, in 10 cases, p53 protein expression was positive while p21 protein expression was negative, and in 6 cases, p53 protein expression was negative whereas p21 protein expression was positive. Consequently a statistically significant inverse correlation between the expression rate of p53 protein and that of p21 protein was observed (p<0.05). In conclusion, we found a significant correlation between histological differentiation and the expression rate of p53 and p21 proteins (p<0.05), and a significant inverse correlation between the expression rate of p53 protein and that of p21 protein (p<0.05). Also, it could be confirmed that the over expression of p53 and p21 proteins is closely associated with the occurrence of colon cancer and its progress. Therefore, it is thought that this study may be greatly beneficial to the presumption of diagnosis, treatment and prognosis of colon cancer patients.

• Journal of the Korean Magnetics Society
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• v.25 no.6
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• pp.175-179
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• 2015

The half-metallicity and magnetism of the (001) surfaces of $(AlP)_1/(CrP)_1$ superlattice were investigated by means of FLAPW (Full-potential Liniarized Augmented Plane Wave) method. We considered four types of (001) surface termination, i.e., Al(S)-, Cr(S)-, P(S)Al(S-1)- and P(S)Cr(S-1)-term systems. We found that only Cr(S)-term system maintains the half-metallicity at the surface as only this system has the calculated magnetic moment of integer number of bohr magnetons. The magnetic moment of Cr(S) atom in the system was $3.02{\mu}_B$ which was increased from the bulk value by the effects of band narrowing and increased spin-splitting at the surface. The electronic density of states of the P(S) atom in the P(S)Al(S-1)-term showed very sharp surface states due to the broken $p_z$ bonds at the surface. We found there is still a strong p-d hybridization between the P(S) and Cr(S-1) layers in the P(S)Cr(S-1)-term which causes a considerable increase of magnetic moment of P(S) atom.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.318-323
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• 1992

Following seven new nucleophilic adducts of sulfilimine compounds were prepared by the addition of 1-methyl-5-mercapto-1,2,3,4-tetrazole to vinylsulfilimine derivatives; S-Phenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-p-tolyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-m-tolyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-p-chlorophenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-p-bromophenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine, S-p-methoxyphenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine and S-p-nitrophenyl-S-2-(1-methyl-1,2,3,4-tetrazole-5-thio)-ethyl-N-p-tosylsulfilimine. The structures of these adducts were confirmed by elemental analyses, MP, UV, IR-and NMR-Spectra.

• Journal of Korea Foresty Energy
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• v.22 no.2
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• pp.1-17
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• 2003

Populus species have been as a model species in tree breeding and we have enormous varieties resulting from the poplar breeding because of their fast growth performance and short rotation age. New varieties developed in Korea are common italian poplar(P euramericana, I-214, I-476), P euramericana“Eco 28”(Italian poplar No.1) and p. deltoides“Lux”(Italian poplar No.2), which were introduced from foreign countries. As hybrid polars, Hyun-Sasi(p. alba ${\times}$ P. glandulosa No.1, No.2, No.3, No4.), P. nigra x P. maximowiczii and P. koreana x P. nigra val. italica, were developed, and P. davidiana was selected as the result of selection breeding The total plantation areas covered with the new varieties are 935,162ha that include 745,773ha of P. euramericana, 184,636ha of P. alba x P. glandulosa, and other new varieties are 4,735ha. The new poplars are contributed to increase farmer's income as well as bare land tree-planting in Korea. The technologies associated with the poplar species were developed, such as the determination of optimum site for new the poplar species, the crossing method between incompatible poplar species, and the vegetative mass propagation. In the future, poplar species will be considered for phytoremediation species at contaminated areas such as landfill sites or with lives stock's waste water as well as wood production, a shade tree like road-side tree and public park tree.

• Journal of dental hygiene science
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• v.4 no.2
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• pp.85-90
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• 2004

The purpose of this study was to examine what made dental hygiene students choose their major subject and how much they were satisfied with that in an effort to pave the way for more successful guidance. The subjects in this study were 320 dental hygiene students from five colleges in Gyeonggi province, Incheon, Gangweon province, north Gyeongsang province and north Jeolla province. 32 freshmen and 32 sophomores each were selected from the colleges.

• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.245-258
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• 2005

In this paper we prove that the alternating groups A_n, for n = p, p+1, p+2 and symmetric groups $S_n$, for n = p, p+1, where p$\ge$3 is a prime number, can be uniquely determined by their order components. As one of the important consequence of this characterization we show that the simple groups An, where n = p, p+1, P+2 and p$\ge$3 is prime, satisfy in Thompson's conjecture and Shi's conjecture.