• Asian-Australasian Journal of Animal Sciences
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• v.31 no.3
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• pp.335-343
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• 2018

Objective: Remarkable difference in cellular activity was found between early and late subpassaged embryonic stem cell (ESCs) lines, which can be created by subtle changes in cell manipulation protocol. This study subsequently examined whether post-thaw subculture of early subpassaged ESC lines could further affect the activity of the ESCs. Methods: Fresh (as a control treatment) or cryopreserved F1 hybrid (B6CBAF1) early ESC lines (C57BL/6xCBA) of the 4 (P4) or the 19 passage (P19) were subcultured once, twice or six times under the same condition. The post-thaw survival of the ESCs was monitored after the post-treatment subculture and the ability of cell proliferation, reactive oxygen species (ROS) generation, apoptosis and mitochondrial ATP synthesis was subsequently examined. Results: Regardless of the subculture number, P19 ESCs showed better (p<0.05) doubling time and less ATP production than P4 ESCs and such difference was not influenced by fresh or cryopreservation. The difference between P4 and P19 ESC lines became decreased as the post-treatment subculture was increased and the six times subculture eliminated such difference. Similarly, transient but prominent difference in ROS production and apoptotic cell number was detected between P4 and P19 ESCs only at the 1st subculture after treatment, but no statistical differences between two ESC lines was detected in other observations. Conclusion: The results of this study suggest that post-thaw subculture of ESCs under the same environment is recommended for standardizing their cellular activity. The activity of cell proliferation ability and ATP synthesis can be used as parameters for quality control of ESCs.

• International Journal of Oral Biology
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• v.35 no.4
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• pp.209-214
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• 2010

Cells that have endogenous multipotent properties can be used as a starting source for the generation of induced pluripotent cells (iPSC). In addition, small molecules associated with epigenetic reprogramming are also widely used to enhance the multi- or pluripotency of such cells. Skinderived precursor cells (SKPs) are multipotent, sphereforming and embryonic neural crest-related precursor cells. These cells can be isolated from a juvenile or adult mammalian dermis. SKPs are also an efficient starting cell source for reprogramming and the generation of iPSCs because of the high expression levels of Sox2 and Klf4 in these cells as well as their endogenous multipotency. In this study, valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, was tested in the generation of iPSCs as a potential enhancer of the reprogramming potential of SKPs. SKPs were isolated from the back skins of 5-6 week old C57BL/6 X DBA/2 F1 mice. After passage 3, the SKPs was treated with 2 mM of VPA and the quantitative real time RT-PCR was performed to quantify the expression of Oct4 and Klf4 (pluripotency specific genes), and Snai2 and Ngfr (neural crest specific genes). The results show that Oct4 and Klf4 expression was decreased by VPA treatment. However, there were no significant changes in neural crest specific gene expression following VPA treatment. Hence, although VPA is one of the most potent of the HDAC inhibitors, it does not enhance the reprogramming of multipotent skin precursor cells in mice.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.225-230
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• 1995

The effect of long-term ginseng (Panax ginseng C.A. Meyer) administration on the clearance of carboxyhemoglobin (CO-Hb) and the property of blood gases was investigated in rats. Rats were received ginseng water extract (0.025% in drinking water) for 42 weeks starting at the age of 6 weeks. They were exposed to the diluted mainstream smoke generated from 15 filter cigarettes for 20 min in a round polycarbonate chamber (D37 cmXH13 cm). Under this condition, the mean CO-Hb content of control and the ginseng-treated rats immediately after the exposure was nearly the same as 13.8$\pm$2.9 f) and 13.9$\pm$1.6%, respectively. However, CO-Hb was more rapidly removed from blood in the ginseng treated rats than in untreatEd control with the laps of time, namely, its biological half life In the former was 36.9$\pm$1.5 min and in the latter was 56.9$\pm$13.2 min. Although long-term ginseng treatment did not affect the content of hemoglobin and blood pH of rats, it slightly increased blood oxygen content and its partial pressure value, and decreased levels of carbon dioxide and bicarbonate. These results suggest that long-term administration of rats with ginseng extract accelerate the elimination of CO from the blood. This effect seems to be related to the enhancement of oxygen consumption of the rat by a certain action of ginseng components as previously reported.

• Korean Journal of Weed Science
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• v.16 no.3
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• pp.171-175
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• 1996

Seed occurrence patterns of Echinochloa crus-galli (L) P. Beauv. and Monochoria vaginalis (Burm. f.) Presl. were investigated in irrigated and rainfed rice cultures. There was not much difference in seed population of E. crus-galli between irrigated and rainfed fields, but M. vaginalis occurred in about 1.6-fold greater number in rainfed fields. In seed distribution patterns under the two conditions, about 50% and 30% of E. crus-galli and M. vaginalis, respectively, were found in the uppermost 5cm layer. Under both conditions M. vaginalis was distributed to a depth of 25cm, but distribution of E. crus-galli was only 15cm deep. Early rice transplanting brought about greater emergence of the two weeds than optimal or late transplanting. Emergence of the weeds was significantly greater in single cropping system of rice than in double cropping systems of rice followed by barley and/or strawberry.

• Korean Journal of Materials Research
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• v.19 no.6
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• pp.293-299
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• 2009

The microstructures and mechanical properties of Dual Phase (DP), Transformation-Induced Plasticity (TRIP), and Quenching & Partitioning (Q&P) steels were investigated in order to define the strengthening mechanism of 0.2 C steel. An intercritical annealing between Ac1 and Ac3 was conducted to produce DP and TRIP steel, followed by quenching the DP and TRIP steel being quenched at to room temperature and by the TRIP steel being austemperingaustempered-air cooling cooled the steel toat room temperature, respectively. The Q&P steel was produced from full austenization, followed by quenching to the temperature between $M_s$ and $M_f$, and then enriching the carbon to stabilize the austenite throughout the heat treatment. For the DP and TRIP steels, as the intercritical annealing temperature increased, the tensile strength increased and the elongation decreased. The strength variation was due to the amount of hard phases, i.e., martensite and bainite, respectively in the DP and TRIP steels. It was also found that the elongation also decreased with the amount of soft ferrite in the DP and TRIP steels and with the amount of the that was retained in the austenite phasein the TRIP steel, respectively for the DP and TRIP steels. For the Q&P steel, as the partitioning time increased, the elongation and the tensile strength increased slightly. This was due to the stabilized austenite that was enriched with carbon, even when the amount of retained austenite decreased as the partitioning time increased from 30 seconds to 100 seconds.

• Child Health Nursing Research
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• v.6 no.2
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• pp.158-166
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• 2000

The purpose of this study was to confirm the efficient umbilical cord care of healthy newborns in nursery. In order to determine the efficient care, the time of umbilical cord separation and the skin condition of periumbilical area were evaluated. The data were collected in sample of 529 normal, healthy newborns of C hospital in Seoul, from September 1st, 1999 to January 16th, 2000. The babies were randomly selected and allocated into four groups-alcohol swab/tub bath, alcohol swab/partial bath, natural dry/tub bath, natural dry/partial bath- by the methods of care. The mothers of babies were also surveyed by questionnaire about general characteristics. The data were analyzed by SAS program. The results of this study were as follows : 1. The average gestation period of newborns was 39+3 weeks. The average birth weight was 3.27Kg. In gender of babies, boys were 51.7% and girls were 48.3%. The 65% of newborns were born normal vaginal delivery, 35% were C-section. The feeding methods were 55.3% of the babies fed by mixed type, 22.9% by breast, and 21.8% by bottle. There was no significance among four groups by general characteristics. 2. The average time of umbilical cord separation was 8.27 days(SD=2.3). The time was no difference significantly among four groups(F=1.68, P=0.17). 3. The prevalence of the umbilical care complication did not show differences among four groups( 2=3.93, P=0.27). In conclusion, Nurses have preferred the traditional alcohol swab/partial bath method in care of newborns. But there was no difference among the ways to take care of umbilicus according to this study. The way to naturally is more efficient due to reduce the time and expense in umbilical care for normal babies of nursery. This also matched the change in approach to healthy population from intervention to nonintervention way. This could be suggested in education for normal and healthy babies care at home and nursery as a useful way. Endly, the further study about bacterial colony nda infection rate at umbilicus by ways of care is needed.

• Korean Journal of Agricultural Science
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• v.13 no.2
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• pp.243-254
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• 1986

This study was conducted to select the appropriate types of drop cone for measuring soil hardness and to determine the cone index for the actual field on which rice will be transplanted. One type of drop cone was selected from the results of indoor tests and the selected drop cone was tested at the 56fields of the five different districts in Korea. The results of this study were summarized as follows; 1. Cone type D shows a significant penetrating depth variation comparing the other types of cone on the indoor tests. 2. Six types of cone were tested on the similar state of the actual puddling field. The penetrating depth variation was not significant among the cones but cone type F seemed to be suitable to evaluate the state of puddling because cone type F showed the least repeat variations during the tests. 3. The actual field test from 56 fields showed that the penetrating depth was approximately 11.0-14.4cm on the puddling day and it was 9.2-13.7cm on the transplanting day of which one to three days after puddling. 4. The above results show that the selected drop cone could be used to formulate the state of puddling.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.1
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• pp.83-109
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• 1977

Isogenic lines for glabrous leaf (gl), hull color(gh) and glutinous endosperm (wx) were used to clarify the effects of the gl, gh and wx gene on the grain yield and yield components in rice plant. Eight genotypes: glgl ghgh wxwx, glgl ghgh WxWx, glgl GH-wxwx, glgl GH-WxWx, GL-ghgh wxwx, GL-ghgh WxWx, GL-GH-wxwx and GL-GH-WxWx were evalutated in the backcrossed $F_2$ generation. Significant effects were measured for gl genotypes on heading date, gh genotypes on grain fertility, and wxwx genotypes on number of panicles per hill and 1, 000 grain weight. The grain yield of straw hull and non glutinous lines were higher than gold hull and glutinous lines. The interaction of three genes, gl, gh and wx was significant for heading date, but not significant in other characters. The average value of isogenic lines which were combined with two recessive genes and one dominant gene were lower and the C.V. value was higher than the isogenic lines which were combined with two dominant genes and one recessive gene in all characters except plant height and number of grains per plant. The average value of isogenic line combined with three recessive genes was lower and the C.V. was higher than the isogenic line combined three dominant genes in all characters measured.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.26-32
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• 2014

'Dahan' (Avena sativa L.), a winter oat cultivar for forage use, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute Crop Science (NICS), Rural Development Administration (RDA) in 2011. It was derived from an original cross between $F_1$[Sprinter/73625] and 'Gwiri26'. Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Suwon. A line, 'SO99027-GB-B-113-4-4-3', was selected for cold tolerance and good agronomic characteristics and as a line name of 'Gwiri75'. The line 'Gwiri75' was subsequently evaluated for cold tolerance and forage yield during 3 years in four region such as Yesan, Iksan, Kimjae, and Jeju, from 2009 to 2011 and finally named as 'Dahan'. Though similar in heading date to the check cultivar Samhan, 'Dahan' had tall plant length and lodging resistance. It's average forage dry matter yield harvested at milk-ripe stage was 15.6 ton $ha^{-1}$, compared with 14.1 ton $ha^{-1}$ of check cultivar. Cultivar 'Dahan' was lower to the check cultivar 'Samhan' in protein content (8.4% and 9.9%, respectively), while it was superior to the check cultivar in total digestible nutrients (TDN) (60.8% and 59.3%, respectively), and in TDN yield $ha^{-1}$ (9.5 ton and 8.4 ton, respectively). Fall sowing of 'Dahan' is recommended only in the areas where daily minimum mean temperatures are averaged higher than $-7^{\circ}C$ in January, and excluded in mountain area where frost damage is presumable.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.674-684
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• 2018

The purpose of this study is to construct ecological pond using LID technique in order to create naturally comfortable community space in urban idle space. The specification of the ecological pond is $110m^2$ of surface area, $0.45{\pm}0.02m$ of average depth, and bed material is composed of gravel (diameter ${\leq}60mm$), sand (diameter ${\leq}2mm$) and bentonite. Rainfall and water depth monitoring were conducted to determine the annual characteristics of inflow of the water for the ecological pond, result of total rainfall was 1,287 mm and showed a seasonal imbalance that accounted for 71.3% (918 mm) during July to August, but the annual mean water depth was kept constant at $0.45{\pm}0.02m$ due to the secondary water source. Annual trends of basic water quality showed a significant changes according to the season, such as water temperature ($5.2{\sim}28.8^{\circ}C$), DO (5.0 ~ 13.8 mg/L), EC ($113{\sim}265{\mu}S/cm$). BOD, COD, TN, and TP in physicochemical water quality tended to increase after October, but the ion parameters such as $NH_3$ and $PO_4{^{3-}}$ were generally low. Phytoplankton indicators Chl-a and BGA (blue green algae) showed a sharp increase from July to August, and green algae (Selenastrum bibraianum, Pediastrum boryanum etc.) and filamentous blue green algae (Phormidium sp.) emerged as a dominant species. The ion parameters ($F^-$, $Na^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$) were strongly correlated with the $Cl^-$ as a conservative substance (R=0.70~0.97, p<0.05). Water quality was influenced by the ambient environment such as seasonal changes or rainfall, and it was closely related to fluctuation of the inflow of the water. In the future, it is necessary to consider ecological connections by referring to the characteristics surveyed in this study in order to effectively manage the water quality and biodiversity of the ecological pond in idle space.