• Mycobiology
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• v.33 no.2
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• pp.109-112
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• 2005

The internal transcribed spacer (ITS) regions including the 3'-end of 18S rRNA gene, 5.8S rRNA gene and the 5'-end of the 28S rRNA gene of Rhizopus spp. were amplified by PCR and analyzed by DNASIS program. Length polymorphism of these region ranged from 564 bp in R. oryzae to 789bp in R. stolonifer. The length and sequence of 5.8S was very conserved with $154{\sim}155\;bp$. The sequence of ITS2 was more variable than that of ITS1. The base substitution rates were ranged from 0 to 0.6069 per site, and higher rate was found in R. stolonifer. In general, transition was usually more frequent than transversion. On the basis of sequencing results, four groups were clustered with value of 61.9% similarity; R. oryzae, R. micros pores, R. homothallicus, and R. stolonifer groups.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.869-876
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• 2015

Wild relative species of domesticated crops are useful genetic resources for improving agronomic traits. Cytogenetic investigations based on chromosome composition provide insight into basic genetic and genomic characteristics of a species that can be exploited in a breeding program. Here, we used FISH analysis to characterize the ploidy level, chromosome constitution, and genomic distribution o f 5S and 4 5S r ibosomal DNA (rDNA) in four wild Cucurbitaceae species, namely, Citrullus lanatus (Thunb.) Mansf. var. citroides L. H. Bailey (2n = 22), Melothria japonica Maxim. (2n = 22), Sicyos angulatus L. (2n = 24), and Trichosanthes kirilowii Maxim. (2n = 66, 88, 110 cytotypes), collected in different areas of Korea. All species were diploids, except for T. kirilowii, which included hexa-, octa-, and decaploid cytotypes (2n = 6x = 66, 8x = 88, and 10x = 110). All species have small metaphase chromosomes in the range of $2-5{\mu}m$. The 45S rDNA signals were localized distally compared to the 5S rDNA. C. lanatus var. citroides and M. japonica showed one and two loci of 45S and 5S rDNA, respectively, with co-localization of rDNA signals in one M. japonica chromosome. S. angulatus showed two co-localized signals of 5S and 45S rDNA loci. The hexaploid T. kirilowii cytotype showed five signals each for 45S and 5S rDNA, with three being co-localized. This is the first report of hexaploid and decaploid cytotypes in T. kirilowii. These results will be useful in future Cucurbitaceae breeding programs.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.3 s.174
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• pp.794-802
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• 2000

Since the examination of CTOD problem revealed that the discrepancy among CTOD's was a matte., of definition, the relationships among parameters based on different definitions have been studied Particularly, the relationship between $\sigma$BS R-curve based on BS 7448 and R-curve based on the recently introduced $\sigma$5 parameter was investigated in this research. For the comparison, compact tension specimens of used 1Cr-0.5Mo steel, heat treated 1Cr-0.5Mo steel to mimic the new one, A12024-T6, and A12024-T351 were prepared and tested. Consequently, the relationship between $\sigma$5 and $\sigma$BS R-curves for tested materials were established by shifting the rotational center which could determined by rotation factor and ligament size.

• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.194-199
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• 1995

A portion (7.4 kb) of ribosomal DNA tandem repeat unit from a genome of the mushroom T. matsutake has been cloned. A 1.75 kb EcoRI fragment was cloned first using S. cerevisiae 255 rRNA gene as a probe, and this was then used for further cloning. A chromosomal walking experiment was carried out and the upstream region of the 1.75 kb fragment was cloned using SmaI/BamHI enzyme, the size was estimated to be 5.2 kb in length. Part of the downstream region of the 1.75 kb fragment was also cloned using XbaI/BamHI enzymes. Restriction enzyme maps of three cloned DNA fragments were constructed. Northern hybridization, using total RNA of T. matsutake, and the restriction fragments of three cloned DNAs as probes, revealed that all four ribosomal RNA genes (large subunit[LSU], small subunit [SSU], 5.85 and 5S rRNA genes) are present in the cloned region. The gene organization of the rDNA are regarded as an intergenic spacer [IGS]2 (partial) - SSU rRNA - internal transcribed spacer [ITS]1 - 5.8S rRNA - ITS2 - LSU rRNA - IGS1 -5S rRNA - IG52 (partial).

• Korean Journal of Medicinal Crop Science
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• v.18 no.3
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• pp.186-190
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• 2010

The chromosome number was identified and fluorescence in situ hybridization(FISH) mapping of 5S and 45S rDNAs were conducted for C. minima and C. lanceolata in the genus Codonopsis from Jeju island. In this study, we have confirmed that the somatic metaphase chromosome number determined as 2n=2x=16 was the same as the findings from the previous studies. While the conventional staining method makes it rather difficult to distinguish satellite chromosomes due to high degree of variability, FISH analysis produced the exact number and location of 5S and 45S rDNAs. Both species in the genus Codonopsis have a pair of 5S rDNA and their gene loci were observed on chromosome 3. Although two pairs of 45S rDNAs (one on chromosome 1 and the other on chromosome 8) were identified in both species, the 45S rDNA signals on chromosome 8 in C. minima were significantly weaker than those on chromosome 1. In addition, the 45S rDNA signals on chromosome 1 in C. lanceolata showed that the chromosome is non-homologus. In this study, we have determined cytogenetic characteristics of C. minima and C. lanceolata according to their gene replication patterns.

• Toxicological Research
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• v.8 no.2
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• pp.217-233
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• 1992

This study was performed to determine the toxic effects of graded dose levels of SKI 2053R after repeated administration. Three groups of Sprague-Dawley rats(10M and 10F per group) were given a total of 25 i.v. injections of SKI 2053R (1.50,3.75,9.38mg/kg/day). In order to compare the toxic effects of SKI 2053R with those of cisplatin, one group of Sprague-Dawley rats (10M and 10F per group) were given a total of 25 i.v.injections of cisplatin (1.70mg/kg/day). The dosing schedule was divided into five courses of 5 consecutive days with 16-day dose-free intervals between each course. No drug-related toxicity occurred in low dose level group (1.50mg/kg/day) of SKI2053R. From the results of hematological examination, peripheral WBC counts, RBC counts and hemoglobin of high dose level group(9.38mg/kg/day)of SKI 2053R were significantly lower than those of no-treated group. Other toxicities including reduced final body weight, proteinuria and hematuria were observed in high dose level group of SKI 2053R. But, no change was detected in serum biochemical values of SKI 2053R treated groups. All of the rats in cisplatin treated group were died between 3 and 13 weeks, while rats treated with SKI2053R survived to the end except one rat of middle dose level group(3.75mg/kg/day). In histopathological examinations, rats that received cisplatin manifested severe tubular damage in kidney and hemosiderosis in spleen, but no critical pathological lesion was observed in rats of other groups. Considering the results of this study, it was concluded that non-toxic dose of SKI 2053R in this treatment schedule was estimated to be 3.75 mg/kg/day and the maximum tolerated dose was to be higher than 9.38mg/kg/day. The toxic profiles fo SKI 2053R were different from those of cisplatin, and its toxicity was considerably lower than that of cisplatin.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.73-73
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• 1993

As part of a research program to develope 3rd generation anti tumor platinum complexes, a series of platinum complexes which have 4, 5-bis-(aminomethyl)- 1, 3-dioxolane derivatives as bidenate amine ligands, represented by the general structual formula was prepared. The R$_1$ and/or R$_2$ substituents in this series of platinum complexes can be hydrogen. alkyl, of jointly formed cyclohexane. Two Xs can be a bidenate leaving ligand such as 1, 1-cyclobutanedicarboxylate, malonate, dimethylmalonate, ethylmalonate, glycolate, L-lactate, or N-methyliminodiacetate. From based on the pharmacological and toxicological studies, we have chosen SKI 2053R, cis-malonato[(4R, 5R)-4, 5-bis(aminomethyl)-2-isopropyl-1, 3-dioxolane] platinum(II) complex (NSC D644591) as a candidate for clinical evaluation. The antitumor activity of a new anti tumor platinum complex, cis-malonato [(4R, 5R)-4, 5-bis(aminomethyl)-2-isopropyl-1, 3-dioxolane] platinum(II) (SKI 2053R, NSC D644591), was compared with those of cisplatin and carboplatin using murine tumors. We evaluated three platinum complexes against L1210/CPR, a subline of L1210 leukemia resistant to cisplatin for their abilities to overcome tumor resistance to cisplatin. The in vitro cytotoxicity of SKI 2053R to L1210 cell line was 2.5-fold less potent thann that of cisplatin, and was 10-fold more cytotoxic than that of carboplatin. SKI 2053R retained similar cytotoxic effect and anti tumor activity to L1210/CPR cell line, like the cytotoxicity of SKI 2053R to L1210 cell line, while either cisplatin or carboplatin had not property to overcome the acquired cisplatin-resistance. SKI 2053R exhibited greater or comparable antitumor activity than cisplatin or carboplatin in murine tumor models.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.5
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• pp.695-698
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• 2009

In this paper, we introduce the concept of fuzzy r-generalized open sets which are generalizations of fuzzy r-open sets defined by Lee and Lee [2] and obtain some basic properties of their structures. Also we introduce and study the concepts of fuzzy r-generalized continuous mapping, fuzzy r-generalized open mapping and fuzzy r-generalized closed mapping.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.12
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• pp.837-844
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• 2010

In this study, performance of R1234yf and R1234yf/R134a mixture is measured on a heat pump bench tester in an attempt to substitute R134a used widely in mobile air conditioners (MACs). The bench tester is equipped with a open type compressor providing a nominal capacity of 3.5 kW. All tests are conducted under the summer cooling and winter heating conditions of 7/4 $5^{\circ}C$ and $-7/41^{\circ}C$ in the evaporator and condenser, respectively. For R1234yf/R134a mixture, measurements are made at 5%, 10%, and 15% of R134a by mass. Test results show that the coefficient of performance (COP) and capacity of R1234yf are up to 2.7% and 4.0% lower than those of R134a, respectively. For R1234yf/R134a mixture, the COP and capacity are up to 3.9% lower and 3.6% higher than those of R134a. For R1234yf and R1234yf/R134a mixture, the compressor discharge temperature is $4.1{\sim}6.7^{\circ}C$ lower than that of R134a while the amount of charge is reduced up to 11% as compared to R134a. 90%R1234yf/10%R134a is a better refrigerant than pure R1234yf in that it is less flammable and more compatible with existing R134a system. Based upon the results, it is concluded that R1234yf and R1234yf/R134a mixture are long term environmentally friendly solutions to mobile air-conditioners due to their excellent environmental properties with acceptable performance.

• Earthquakes and Structures
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• v.16 no.2
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• pp.185-196
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• 2019

One of the shortcomings of seismic bridge design codes is the lack of clarity in defining the role of different seismic isolation systems with linear or nonlinear behavior in terms of R-factor. For example, based on AASHTO guide specifications for seismic isolation design, R-factor for all substructure elements of isolated bridges should be half of those expressed in the AASHTO standard specifications for highway bridges (i.e., R=3 for single columns and R=5 for multiple column bent) but not less than 1.50. However, no distinction is made between two commonly used types of seismic isolation devices, i.e., elastomeric rubber bearing (ERB) with linear behavior, and lead rubber bearing (LRB) with nonlinear behavior. In this paper, five existing bridges located in Iran with two types of deck-pier connection including ERB and LRB isolators, and two bridge models with monolithic deck-pier connection are developed and their R-factor values are assessed based on the Uang's method. The average R-factors for the bridges with ERB isolators are calculated as 3.89 and 4.91 in the longitudinal and transverse directions, respectively, which are not in consonance with the AASHTO guide specifications for seismic isolation design (i.e., R=3/2=1.5 for the longitudinal direction and R=5/2=2.5 for the transverse direction). This is a clear indicator that the code-prescribed R-factors are conservative for typical bridges with ERB isolators. Also for the bridges with LRB isolators, the average computed R-factors equal 1.652 and 2.232 in the longitudinal and transverse directions, respectively, which are in a good agreement with the code-specified R-factor values. Moreover, in the bridges with monolithic deck-pier connection, the average R-factor in the longitudinal direction is obtained as 2.92 which is close to the specified R-factor in the bridge design codes (i.e., 3), and in the transverse direction is obtained as 2.41 which is about half of the corresponding R-factor value in the specifications (i.e., 5).