• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.319-324
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• 1997

Despite the direct placement of sperm within the oocyte, fertilization failure still occurs after ICSI. This study was accomplished to analyze the chromosomes in oocytes failed to fertilize after ICSI comparing to oocytes failed to fertilize by conventional in vitro insemination. Seventy-four ICSI cycles and 122 conventional IVF cycles were included in analysis. Included unfertilized oocytes were from 74 patients (mean age = $32.7{\pm}3.7$). Ninety-three oocytes were informative and 83 oocytes were legible for cytogenetic analysis. Sixty-two oocytes out of 83 (74.7%) had normal chroruosomes, while 15 (18.1%) were hypoploidy, 6 (7.2%) were hyperploidy. Eighteen oocytes out of 93 (17.6%) were premature chromosome condensation (PCC). Two hundred ninety-four unfertilized oocytes after conventional insemination were subjected to chromosomal analysis and 180 oocytes were legible for analysis. One hundred thirty-two oocytes out of 180 (73.3%) were normal, while 22 (12.2%) were hypoploidy, 20 (11.1%) were hyperploidy, and 6 (3.3%) were polyploidy. Twenty-two oocytes (12.2%) were PCC. There was no difference in chromosomes between oocytes that failed to fertilize after ICSI or conventional insemination. High PCC rates in fertilization-failed oocytes suggest that oocytes maturity is another important factor in achieving successful fertilization.

• Earthquakes and Structures
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• v.8 no.3
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• pp.761-778
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• 2015

The objective of this paper is to report the result of an experimental program conducted on the strengthening of nonductile RC frames by using external mesh reinforcement and plaster application. The main objective was to test an alternative strengthening technique for reinforced concrete buildings, which could be applied with minimum disturbance to the occupants. Generic specimen is two floors and one bay RC frame in 1/2 scales. The basic aim of tested strengthening techniques is to upgrade strength, ductility and stiffness of the member and/or the structural system. Six specimens, two of which were reference specimens and the remaining four of which had deficient steel detailing and poor concrete quality were strengthened and tested in an experimental program under cyclic loading. The parameters of the experimental study are mesh reinforcement ratio and plaster thickness of the infilled wall. The effects of the mesh reinforced plaster application for strengthening on behavior, strength, stiffness, failure mode and ductility of the specimens were investigated. Premature and unexpected failure mode has been observed at first and second specimens failed due to inadequate plaster thickness. Also third strengthened specimen failed due to inadequate lap splice of the external mesh reinforcement. The last modified specimen behaved satisfactorily with higher ultimate load carrying capacity. Externally reinforced infill wall composites improve seismic behavior by increasing lateral strength, lateral stiffness, and energy dissipation capacity of reinforced concrete buildings, and limit both structural and nonstructural damages caused by earthquakes.

• Steel and Composite Structures
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• v.12 no.4
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• pp.291-302
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• 2012

Frequently, steel silos are supported by discrete supports or columns to permit easy access beneath the barrel. In such cases, large loads are transferred to the limited number of supports, causing locally high axial compressive stress concentrations in the shell wall above the supports. If not dealt with properly, these increased stresses will lead to premature failure of the silo due to local instability in the regions above the supports. Local stiffening near the supports is a way to improve the buckling resistance, as material is added in the region of elevated stresses, levelling these out to values found in uniformly supported silos. The aim of a study on the properties of local stiffening will then be to increase the failure load, governed by an interaction of plastic collapse and elastic instability, to that of a discrete supported silo. However, during the course of such a study it was found that, although the failure remains local, the cylinder height is also a parameter that influences the failure mechanism, a fact that is not properly taken into account in current design practice and codes. This paper describes the mechanism behind the effect of the cylinder height on the failure load, which is related to pre-buckling deformations of the shell structure. All results and conclusions are based on geometrically and materially non-linear finite element analyses.

• The Korean Journal of Mycology
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• v.48 no.3
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• pp.329-335
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• 2020

From 2008 to 2017, Korean azalea (Rhododendron yedoense f. poukhanense) showing angular, necrotic leaf spots were found in Jeju and Hongcheon, Korea. The lesions occurred frequently, detracting from the beauty of the glossy green leaves of the plant and causing premature defoliation. Therefore, to identify the fungus associated with the lesions, morphological characterization and molecular phylogenetic analysis of actin (Act), translation elongation factor 1-alpha (EF), internal transcribed spacer (ITS), 28S nrDNA (LSU), and RNA polymerase II encoding the second largest subunit (RPB2) of the two representative isolates were performed. The phylogenetic tree inferred from the neighbor-joining method showed the isolates clustering in the Sphaerulina azaleae group. Therefore, the fungus associated with the angular leaf spots on the Korean azalea was identified as Sphaerulina azaleae.

• Journal of Ginseng Research
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• v.41 no.1
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• pp.69-77
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• 2017

Background: Human skin undergoes distinct changes throughout the aging process, based on both intrinsic and extrinsic factors. In a process called photoaging, UVB irradiation leads to upregulation of matrix metalloproteinase-1, which then causes collagen degradation and premature aging. Mixtures of medicinal plants have traditionally been used as drugs in oriental medicine. Based on the previously reported antioxidant properties of Panax ginseng Meyer and Crataegus pinnatifida, we hypothesized that the mixture of P. ginseng Meyer and C. pinnatifida (GC) would have protective effects against skin aging. Methods: Anti-aging activity was examined both in human dermal fibroblasts under UVB irradiation by using Western blot analysis and in healthy human skin by examining noninvasive measurements. Results: In vitro studies showed that GC improved procollagen type I expression and diminished matrix metalloproteinase-1 secretion. Based on noninvasive measurements, skin roughness values, including total roughness (R1), maximum roughness (R2), smoothness depth and average roughness (R3), and global photodamage scores were improved by GC application. Moreover, GC ameliorated the high values of smoothness depth (R4), which means that GC reduced loss of skin moisture. Conclusion: These results suggest that GC can prevent aging by inhibiting wrinkle formation and increasing moisture in the human skin.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.1
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• pp.57-63
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• 1994

We use a variety of methods to determine the optimum time for havesting corn for silage. In addition, adequate dry matter for silage must be considered along with maturity stage. The objective of this study was to evaluate using the kernel milk line to determine when to harvest com for silage in 1992 on the Livestock Experimental F m , Keiymung Junior College at Keongsan, Keongsangbukdo. Four hybrids were field grown and com plants were harvested at various stages of kernel development so that kemel milk line movement could be analyzed whilc the corn was in the premature stages. As the plants approached maturity, the ears were collected from each of the hybrids and the position of the milk line wa5 noted. Then the whole plants were chopped and the content of DM was determined. The milk line was a readily identifiable feature of maturing com kemels. We focused on the five development \tage\. The fint was "soft dough". The second was "dent". The third wa, "75% milk". and the fourth wa5 "half milk". The half milk occurs when the milk line is positioned falf way down the kemel face. and the final stages win "no milk", milk disappearance as indicators of physiological maturity in maix. Milk free stage of the kemel occurred from I to 3 days prior to black layer having developed. The range for harvesting com for silage occurs a kemels mature from 75% milk to no milk. Position of milk line was easy to see. and can be used as a visible indicator to determine com matunty stage\ and whole plant dry matter. Whole plant dry matter increased with advancing maturity. averaged over hybrids it was 24.1, 25.6. 28.5. 34.6 and 39.0% at soft dough, dent, 75% milk. half milk and no milk. Milk line was more usehl indicator in monitoring corn maturity prior to physiological maturity.ing corn maturity prior to physiological maturity.

• Journal of the Korea Convergence Society
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• v.9 no.3
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• pp.279-287
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• 2018

This study was to investigate the factors affecting the obstetric outcomes of married immigrant women and to compare the results with the Korean women's and to provide basic data for establishing effective nursing interventions for the married immigrant women. The subjects were 302 married immigrant women and Korean women who were delivered in the university hospital from 2011 to 2015. Data were analyzed using frequency, mean, standard deviation and logistic regression using SPSS WIN 24.0 program. Factors affecting obstetric outcome were premature rupture of membranes, gestational hypertension, amniotic fluid abnormalities, and medical illness in both married immigrant women and Korean women. In addition, age, spouse's age, occupation, hemoglobin level, and placental abnormality were found to have an effect on obstetrical outcome in married immigrant women. Therefore, in order to improve the obstetric outcome of married immigrant women, a prenatal care program considering these influencing factors will be needed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.2
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• pp.450-460
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• 2017

T wave is cardiac parameters that represent ventricular repolarization, it is very important to diagnose arrhythmia. Several methods for detecting T wave have been proposed, such as frequency analysis and non-linear approach. However, detection accuracy is at the lower level. This is because of the overlap of the P wave and T wave depending on the heart condition. We propose T wave detection algorithm based on target area extraction through QRS cancellation and moving average. For this purpose, we detected Q, R, S wave from noise-free ECG(electrocardiogram) signal through the preprocessing method. And then we extracted P, T target area by applying decision rule for four PAC(premature atrial contraction) pattern another arrhythmia through moving average and detected T wave using RT interval and threshold of RR interval. The performance of T wave detection is evaluated by using 48 record of MIT-BIH arrhythmia database. The achieved scores indicate the average detection rate of 95.32%.

• Journal of Embryo Transfer
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• v.12 no.3
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• pp.307-313
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• 1997

Experiments were conducted to assess the effect of quality and viability of bovine blastocysts derived from in-vitro culture(IVC) of in vitro matured and fertilized(IVM-IVF) oocytes during their transport 2 hours. Follicular oocytes were collected form ovaries obtained at a slaughterhouse and were cultured for 24 hours in TCM-199. The IVM oocytes were fertilized in vitro with caudal epididymis spermatozoa. Fertilized oocytes were cultured for 7 to 9 days, and embryos that developed to the blastocyst stage were used for the experiment. The blastocysts, packed in straws with storage medium that consisted TCM-199 with HEPES equilibratd in air and supplemented with 10% FCS were transported at 39~(2.0 h). The quality of blastocysts was assessed and ranked as A(excel-lent), B(Good), fair or poor after transportation. The percentages of A and B grade blastocysts after transport duration for < 1 hours(97.7%) were similar to the result from transport duration for 1~2 hours (92.9%) and 2~3 hours(89.6%), but significantly(P<0.05) higher than transpot duration for 3~4 hours(76.3%). The percentages of A and B grade blastocysts after transport duration for two hours from developed blastocyst at 7day(100%) and 8day(85.0%) were higher 9day(96.6%) and >9day (40.0%). And early to expanded blastocyst produced in vitro were transferred to recipient cow by additional embryos at 7 and 8th day after AI. Three of them were pregnant to term and produced four twin calves, and two calves was premature birth. The gestation lengths of male to female and female to female twin were 282 and 281 days, respectively. And birth weight of twin calves were male to female(22.Skg) and female to female twin(20.3Okg), respectively.

• Korean Journal of Animal Reproduction
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• v.16 no.2
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• pp.103-107
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• 1992

The present study was conducted to find out the changes of progesterone levels in pre and post partum by the PGF2$\alpha$ administration to control artificial parturition in Korean native goats. A total of 24 goats were offered for this experiment. The animals were divided into 4 goats per treatment by the administration time(142, 145 or 148 day of pregnancy). Blood samples were taken from jagular vein pre-post partum by the PGF2$\alpha$ intramuscular administration. The progesterone in serum was assayed by radioimmunoassay. The serum progesterone level in late-pregnant goats averaged 4.85$\pm$0.55ng/ml, 4.05$\pm$0.47ng/ml or 2.76$\pm$0.25ng/ml on 142, 145 or 148 days of gestation. After the intramuscular injection with PGF2$\alpha$ for inducing parturition, it decreased remarkably to below 1.0ng/ml and to the base level(0.4~0.6ng/ml) at day 1 after parturition. And then this base level of progesterone was maintained until the final examination at 9 days of postpartum. No significant difference was found in the serum levels of progesterone between the doses treated for parturition induction. It was concluded that exogenous PGF2$\alpha$, administrated intramuscularly, induced premature parturition with causing withdrawal of progesterone levels for triggering luteolysis.