• Restorative Dentistry and Endodontics
• /
• v.31 no.6
• /
• pp.452-459
• /
• 2006

Competition will usually develop between the opposing walls as the restorative resin shrinks during polymerization. Magnitude of this phenomenon may be depended upon cavity configuration and volume. The purpose of this sturdy was to evaluate the effect of cavity configuration and volume on microleakage of composite resin restoration that has margins on the enamel site only. The labial enamel of forty bovine teeth was ground using a model trimmer to expose a flat enamel surface. Four groups with cylindrical cavities were defined, according to volume and configuration factor(Depth x Diameter / C-factor) - Group I : 1.5 mm ${\times}$ 2.0 mm / 4.0, Group II : 1.5 mm ${\times}$ 6.0 mm / 2.0, Group III : 2.Omm ${\times}$ 1.72 mm / 5.62, Group IV : 2.0 mm ${\times}$ 5.23 mm / 2.54. After treating with fifth-generation one-bottle adhesive - BC Plus$^{TM}$ (Vericom, AnYang, Korea), cavities were bulk flted with microhybrid composite resin - Denfill$^{TM}$ (Vericom). Teeth were stored in distilled water for one day at room temperature and were finished and polished with Sof-Lex system. Specimens were thermocycled 500 times between 5$^{\circ}$C and 55$^{\circ}$C for 30 second at each temperature. Teeth were isolated with two layers of nail varnish except the restoration surface and 1 mm surrounding margins. Electrical conductivity (${\mu}$A) was recorded in distilled water by electrochemical method. Microleakage scores were compared and analyzed using two-way ANOVA at 95% level. The results were as follows: 1. Small cavity volume showed lower microleakage score than large one, however, there was no statistically significant difference. 2. There was no relationship between cavity configuration and microleakage. Factors of cavity configuration and volume did not affect on microleakage of resin restorations with enamel margins only.

• Food Science and Preservation
• /
• v.16 no.5
• /
• pp.612-617
• /
• 2009

Kimchi is a traditional pickled food using Korean Chinese cabbage(Brassica campestris var. pekinensis) and also containing phytochemicals, glucosinolates. This study was carried out to investigate the changes in the total glucosinolates levels of Kimchi using Korean Chinese cabbage of harvest time(June-July, August-September, October-November, December-April, May) according to storage temperature(4, 10, $15^{\circ}C$) and storage duration(0, 1, 3, 5, 7, 10, 14, 21 and 28 day). For determination of glucosinolates, 50g of Baechu kimchi was used for analytical sample preparation provided with an anion exchanges column and measured by UV-visible Spectrophotometer. The highest contents of water occurred at August-September during fermentation. At 15, 10, $4^{\circ}C$, the pH in all of seasonal variation of Baechu kimchi declined, especially from 0 to 3 days at $15^{\circ}C$, from 0 to 7 days at $10^{\circ}C$ and from 0 to 14 days at $4^{\circ}C$. At that storage, the total glucosinolates levels in all of seasonal variation of Kimchi declined in storage temperature. Baechu kimchi at August-September showed the highest total glucosinolates levels. Also total glucosinolates levels decreased as storage period increased. Baechu kimchi fermented at $15^{\circ}C$ for 7days decreased rapidly and reached to the lowest at the 1day(ranged from $10.3{\pm}0.70$ to $23.4{\pm}0.37{\mu}mol/g$ dry weight). At $10^{\circ}C$ for 14days were ranged from $12.9{\pm}0.29$ to $33.7{\pm}1.81{\mu}mol/g$ dry weight before fermentation and decreased rapidly at the 3day(ranged from $9.5{\pm}0.54$ to $20.5{\pm}0.61{\mu}mol/g$ dry weight). Total glucosinolates levels of Baechu kimchi fermented at $4^{\circ}C$ for 28days decreased rapidly during 7day(ranged from $9.9{\pm}0.78$ to $21.1{\pm}0.96{\mu}mol/g$ dry weight) and then slowly decreased. Therefore the total glucosinolates levels decreased during storage time and depended on harvest time and storage conditions of Kimchi.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.3
• /
• pp.1-40
• /
• 1965

To measure variations in some of the important agronomic characteristics of rice varieties under shifting of seedling dates, this study has been carried out at the Paddy Crop Division of Crop Experiment Station(then Agricultural Experiment Station) in Suwon for the period of three years 1958 to 1960. The varieties used in this study were Kwansan, Suwon ＃82, Mojo, Paltal and Chokwang, which have the different agronomic characteristics such as earliness and plant type. Seeds of each variety were sown at 14 different dates in 10-day interval starting on March 2. The seedlings were grown on seed bed for 30, 40, 50, 60, 70 and 80 days, respectively. The results of this study are as follows: A. Heading dates. 1. As the seeding date was delayed, the heading dates was almost proportionally delayed. The degree of delay was higher in early varieties and lower in late varieties and the longer the seedling stage, the more delayed the heading date. 2. Number of days to heading was proportionally lessened as seeding was delayed in all the varieties but the magnitude varied depending upon variety. In other words, the required period for heading in case of late planting was much shortened in late variety compared with early one. Within a variety, the number of days to heading was less shortened as the seedling stage was prolonged. Early variety reached earlier than late variety to the marginal date for the maximum shortening of days to heading and the longer the seeding stage, the limitted date came earlier. There was a certain limit in seeding date for shortening of days to heading as seeding was delayed, and days to heading were rather prolonged due to cold weather when seeded later than that date. 3. In linear regression equation, Y=a+bx obtained from the seeding dates and the number of days to heading, the coefficient b(shortening rate of days to heading) was closely correlated with the average number of days to heading. That is, the period from seeding to heading was more shortened in late variety than early one as seeding was delayed. 4. To the extent that the seedling stage is not so long and there is a linear relationship between delay of seeding and shortening of days to heading, it might be possible to predict heading date of a rice variety to be sown any date by using the linear regression obtained from variation of heading dates under the various seeding dates of the same variety. 5. It was found out that there was a close correlation between the numbers of days to heading in ordinary culture and the other ones. When a rice variety was planted during the period from the late part of March to the middle of June and the seedling ages were within 30 to 50 days, it could be possible to estimate heading date of the variety under late or early culture with the related data of ordinary culture. B. Maturing date. 6. Within (he marginal date for maturation of rice variety, maturing date was proportionally delayed as heading was delayed. Of course, the degree of delay depended upon varieties and seedling ages. The average air temperature (Y) during the ripening period of rice variety was getting lower as the heading date. (X) was delayed. Though there was a difference among varieties, in general, a linear regression equation(y=25.53-0.182X) could be obtained as far as heading date were within August 1 to September 13. 7. Depending upon earliness of a rice variety, the average air temperature during the ripening period were greatly different. Early variety underwent under 28$^{\circ}C$ in maximum while late variety matured under as low as 22$^{\circ}C$. 8. There was a highly significant correlation between the average air temperature (X) during the ripening period, and number of day (Y) for the maturation. And the relationship could be expressed as y=82.30-1.55X. When the average air temperature during the period was within the range of 18$^{\circ}C$ to 28$^{\circ}C$, the ripening period was shortened by 1.55 days with increase of 1$^{\circ}C$. Considering varieties, Kwansan was the highest in shortening the maturing period by 2.24 days and Suwon ＃82 was the lowest showing 0.78 days. It is certain that ripening of rice variety is accelerated at Suwon as the average air temperature increases within the range of 18$^{\circ}C$ to 28$^{\circ}C$. 9. Between number of days to heading (X) related to seeding dates and the accumulated average air temperature (Y) during the ripening period, a positive correlation was obtained. However, there was a little difference in the accumulated average air temperature during the ripening period even seeding dates were shifted to a certain extent. C. Culm- and ear-lengths. 10. In general all the varieties didn't show much variation in their culm-lengths in case of relatively early seeding but they trended to decrease the lengths as seeding was delayed. The magnitude of decreasing varied from young seedlings to old ones. Young seedlings which were seeded during May 21 to June 10 didn't decrease their culm-lengths, while seedlings old as 80 days decreased the length though under ordinary culture. 11. Variation in ear-length of rice varieties show the same trend as the culm-length subjected to the different seeding dates. When rice seedlings aged from 30 to 40 days, the ear-length remained constant but rice plants older than 40 days obviously decreased their ear-lengths. D. Number of panicles per hill. 12. The number of panicles per hill decreased up to a certain dates as seeding was delayed and then again increased the panicles due to the development of numerous tillers at the upper internodes. The seeding date to reach to the least number of panicles of rice variety depended upon the seedling ages. Thirty- to 40-day seedlings which were seeded during May 31 to June 10 developed the lowest number of panicles and 70- to 80-day seedlings sown for the period from April 11 to April 21 reached already to the minimum number of panicles. E. Number of rachillae. 13. To a certain seeding date, the number of rachillae didn't show any variation due to delay of seeding but it decreased remarkably when seeded later than the marginal date. 14. Variation in number of rachillae depended upon seedling ages. For example, 30- to 40-day old seedlings which, were originally seeded after May 31 started to decrease the rachillae. On the other hand, 80-day old seedlings which, were seeded on May 1 showed a tendency to decrease rachillae and the rice plant sown on May 31 could develop narrowly 3 or 4 panicles. F. Defective grain and 1.000-grain weights. 15. Under delay of the seeding dates, weight of the defective grains gradually increased till a certain date and then suddenly increased. These relationships could be expressed with two different linear regressions. 16. If it was assumed that the marginal date for ripening was the cross point of these two lines, the date seemed. closely related with seedling ages. The date was June 10- in 30- to 40-day old seedlings but that of 70- to 80-day old seedlings was May 1. Accordingly, the marginal date for ripening was getting earlier as the seedling stage was prolonged. 17. The 1.000-grain weight in ordinary culture was the heaviest and it decreased in both early and late cultures. G. Straw and rough rice weights. 18. Regardless of earliness of variety, rice plants under early culture which were seeded before March 22 or April 1 did not show much variation in straw weight due to seedling ages but in ordinary culture it gradually decreased and the degree was became greater in late culture. 19. Relationship between seeding dates (X) and grain weight related to varieties and seedling ages, could be expressed as a parabola analogous to a line (Y=77.28-7.44X$_1$-1.00lX$_2$). That is, grain yield didn't vary in early culture but it started to decrease when seeded later than a certain date, as seeding was delayed. The variation was much greater in cases of late planting and prolongation of seedling age. 20. Generally speaking, the relationship between grain yield (Y) and number of days to heading (X) was described with linear regression. However, the early varieties were the highest yielders within the range of 60 to 110, days to heading but the late variety greatly decreased its yield since it grows normally only under late culture. The grain yield, on the whole, didn't increase as number of days to heading exceeded more than 140 days.

• Korean journal of applied entomology
• /
• v.25 no.3 s.68
• /
• pp.159-167
• /
• 1986

White tip nematode damage to rice was surveyed at 111 $My{\check{o}}n$ from 36 Gun in Kyongsangnam-Do, $Ky{\check{o}}ngsangbuk-Do\;and\;Ch{\check{o}}llanam-Do$. Rate of damaged stem by the nematode was highest at $Ch'angny{\check{o}}ng-Gun\;in\;Ky{\check{o}}ngsangnam-Do$ as 28.3%, $Y{\check{o}}ngch'on-Gun\;in\;Ky{\check{o}}ngsangbuk-Do$ as 69.3% and $Pos{\check{o}}ng-Gun\;in\;Ch{\check{o}}llanam-Do$ as 40.6%. In pot experiment, no white tip symptoms were appeared in Tongil hybrids except $W{\check{o}}np'ung$ by 3.4% but a great number of the nematode was detected in seeds while symptom and a fair amount of the nematode were observed in Japonica cultivars. The number of nematode in Shingwang cultivar of Tongil hybrids and Dongin cultivar of Japonica was highest by 1997, by 1023 individuals per 10g of seed respectively. Detection rate of the nematode was different depended upon peeling of the husks. Less than 50% was detected from unhulling seed compared with hulled seed except 8 cultivars such as $Shins{\check{o}}nchal$, Hangangchal, $S{\check{o}}gwang,\;Y{\check{o}}ngpung$, Milyang 23, $Such{\check{o}}ng,\;Taech'{\check{o}}ng\;and\;S{\check{o}}nam$. More effective detection was oftained with temperature level at $25^{\circ}C$ and increased with immersing time regardless of peeling the husks.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.49 no.3
• /
• pp.172-178
• /
• 2004

When soybean sprouts aye grown in the closed condition (where the ratio of $\textrm{O}_2$ and $\textrm{CO}_2$ is 7 ： 3), amount of $\textrm{CO}_2$ is increased and $\textrm{O}_2$ is decreased with the passage of time. At the same time, the amount of ethylene is automatically increased. By increasing the concentration of ethylene gas up to 0.5-1.0 ppm in the growth room, the length of sprouts was restricted to 6-7 cm and the thickness of sprouts was increased to 2.70$\pm$0.30 mm. The production of good quality sprouts which were fat and short was possible without application of any growth regulators such as indole-3-acetic acid known to have accumulation problem in humane body. To maintain the freshness during the transportation and prevent sprouts from rotting and bad smell at market, cold storage at 2-$5^{\circ}$ and airtightness which will restrict photosynthesis and respiration (higher than $10^{\circ}$) are needed. The freshness of sprouts is depended on the increase of $\textrm{CO}_2$ and the depletion of $\textrm{O}_2$ in the package. When the sprouts were stored below 1$0^{\circ}C$ (preferably below 8$^{\circ}C$), the concentration of $\textrm{CO}_2$ in the package remained below 30% for more than 60 hours, which was possible to keep sprouts in freshness without any offensive odor, But sprouts were maintained at $13^{\circ}$ for more than 25 hours, the concentration of $\textrm{CO}_2$ increased over 30% and produced an offensive odor. The little amount of $\textrm{O}_2$ gas was existing for 30 hours at $5^{\circ}$ but it was disappeared completely within 7 hours over $10^{\circ}$ and the sprouts became rot and produced severe offensive odor.

• Journal of Plant Biotechnology
• /
• v.33 no.1
• /
• pp.33-37
• /
• 2006

Bottle gourd (Lagenaria siceraria Standl.) has been used as a rootstock for the watermelon cultivation because of better growth ability at low temperature and avoidance from contamination of the soil disease. Since the genetic source for the elite rootstock is limited in nature, the genetic engineering method is inevitable to develop new lines especially to obtain the functionally important or multi-disease resistant bottle gourd. Recently, our lab has set up a successful system to transform the bottle gourd. in order to monitor the transformation process, GFP gene is used. Cotyledons of the inbred line 9005, 9006 and G5 were used to induce the shoot under the selection media with MS + 30 g/L sucrose + 3.0 mg/L BAP + 100 mg/L kanamycin + 500 mg/L cefotaxime + 0.5 mg/L $AgNO_3$, pH 5.8. The shoot was developed from the cut side of the explants after 3 weeks on the selection media. The shoot was incubated in the rooting media with 1/2 MS + 30 g/L sucrose + 0.1 mg/L IAA + 50 mg/L kanamycin + 500 mg/L cefotaxime, pH 5.8 and moved to pot for acclimation. Although the shoot development rate was depended on the genotype, the G5 was the best line to be transformed. Monitoring GFP expression from the young shoot under microscope could make the selection much easier to distinguish the transformed shoot from the non-transformed shoots.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.10 no.1
• /
• pp.45-53
• /
• 2012

The metal chloride wastes from a pyrochemical process to recover uranium and transuranic elements has been considered as a problematic waste difficult to apply to a conventional solidification method due to the high volatility and low compatibility with silicate glass. In this study, a dechlorination approach to treat LiCl-KCl waste for final disposal was adapted. In this study, a $SiO_2-Al_2O_3-P_2O_5$ (SAP) inorganic composite as a dechlorination agent was prepared by a conventional sol-gel process. By using a series of SAPs, the dechlorination behavior and consolidation of reaction products were investigated. Different from LiCl waste, the dechlorination reaction occurred mainly at two temperature ranges. The thermogravimetric test indicated that the first reaction range was about $400^{\circ}C$ for LiCl and the second was about $700^{\circ}C$ for KCl. The SAP 1071 (Si/Al/P=1/0.75/1 in molar) was found to be the most favorable SAP as a dechlorination agent under given conditions. The consolidation test revealed that the bulk shape and the densification of consolidated forms depended on the SAP/Salt ratios. The leaching test by PCT-A method was performed to evaluate the durability of consolidated forms. This study provided the basic information on the dechlorination approach. Based on the experimental results, the dechlorination method using a $SiO_2-Al_2O_3-P_2O_5$ (SAP) could be considered as one of alternatives for the immobilization of waste salt.

• Horticultural Science & Technology
• /
• v.35 no.2
• /
• pp.210-219
• /
• 2017

This study was conducted to establish an efficient screening method for radish (Raphanus sativus) cultivars that are resistant to black spot, which is caused by Alternaria brassicicola. Seven A. brassicicola isolates were selected and investigated for their ability to produce spores and pathogenicity. Of these isolates, A. brassicicola KACC 40036 and 43923 produced abundant spores in V-8 juice agar medium and showed pathogenicity and strong virulence on radish seedlings. We examined the resistance of 61 commercial cultivars of radish to A. brassicicola KACC40036, and found that there are no highly resistant radish cultivars; however, some cultivars, such as 'Geumbong' and 'Searom', showed weak resistance to A. brassicicola. For further study, we selected four radish cultivars that showed different disease responses to A. brassicicola KACC40036. According to the growth stage of the radish seedlings, inoculum concentration, and incubation temperature of radish, development of black spot on four cultivars has been investigated. The results showed that younger seedlings were more sensitive to A. brassicicola than older seedlings, and the disease severity depended on the concentration of the spore suspension. The disease severity of plants incubated in humidity chamber at $25^{\circ}C$ was greater than that of plants grown at $20^{\circ}C$ or $30^{\circ}C$. Taken together, we suggest the following method for screening for radish plants that are resistant to A. brassicicola: 1) inoculate 16-day-old radish seedlings with an A. brassicicola spore suspension ($2.0{\times}10^5spores{\cdot}mL^{-1}$) using the spray method, 2) incubate the inoculated plants in a humidity chamber at $25^{\circ}C$ for 24 h and then transfer the plants to a growth chamber at $25^{\circ}C$ with 80% relative humidity under a 12 h light/dark cycle, and 3) assess the disease severity of the plants two days after inoculation.

• Journal of Bio-Environment Control
• /
• v.29 no.3
• /
• pp.239-244
• /
• 2020

Effect of 6kg large unit with the carton box (20% open ratio) and MA box (10,000cc·m^-2·day^-1·atm^-1 oxygen transmission rates modified atmosphere package), and the 100g small unit with MA film on asparagus sensory quality were evaluated. The CO₂ concentration depended largely on the packing unit and maintained at around 3% in small MA packages, whereas in the MA box increased to 12%. Ethylene concentration rapidly increased until after 3 days of storage in MA packages and then decreased to maintain 5μL·L^-1. Unrelated to the unit size, the lower weight loss was obtained in MA packages. A significant difference in visual quality was shown since the 15th day, the best and worst were the MA box and small MA package on the finish day. Off-odor was the highest in small MA packages and the lowest in the carton box (< 3.0). Although there was no significant difference in firmness among all treatments, the packages showed the highest firmness in tips and stems, respectively. The sugar content and hue angle decreased during storage, but there was no statistical difference in all treatments. EL was lowest and highest in small MA package and carton box, respectively. On the 10th day, the total aerobic bacteria was lowest in small MA packages, but no significant difference on the 20th day. E. coli was not found in all treatments on the 10th day, while it was the lowest in the MA box on the 20th day. The mold and yeast were not observed during the whole storage. Based on the above results, the carton box packaged with 10,000cc OTR film was more effective in maintaining the quality of green asparagus with the suitable CO₂ concentration for asparagus cold storage.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.12 no.2
• /
• pp.95-106
• /
• 2010

The performance of Community Land Model version 3.5 - Dynamic Global Vegetation Model (CLM-DGVM) was evaluated through a comparison with the observation over temperate deciduous forest in Gwangneung, Korea. Influence of plant phenology, composition of plant functional type, and climate variability on carbon exchanges was also examined through sensitivity test. To get equilibrium carbon storage, the model was run for 400 years driven by the observed atmospheric data at the deciduous forest of the year 2006. We run the model for 2006 with the equilibrium carbon storage at Gwangneung forest and compared the model output with the observation. A comparison of leaf area index (LAI) between the model and observation indicated that the simulated phenology poorly represented the timing of budburst, leaf-fall, and evolution of LAI. Senescence of the phenology was delayed about four weeks and the simulated maximum LAI (of 5.8 $m^2$ $m^{-2}$) was greater than the observed value (of 4.5 $m^2$ $m^{-2}$). The overestimated LAI contributed to overestimation of both gross primary productivity (GPP) and ecosystem respiration $(R_e)$ through increased photosynthesis and foliar autotropic respiration $(R_a)$, respectively. Despite the discrepancy between the simulated and observed LAI, the simulated tree carbon storage amounts were comparable with the reported values at the site. Change in plant phenology from the simulated to the observed reduced more than six weeks of the plant growth period, resulting in the decreased amount of GPP and $R_e$. These values, however, were still higher (~10% of GPP and 40% of $R_e$) than the observed values. The effect of change in plant functional type composition (from dominant temperate deciduous forest to the coexistence of temperate deciduous and needle leaf forests) on the estimated amount of GPP and $R_e$ was marginal. The influence of climate variability on carbon storage amounts was not significant. The simulated inter-annual variation of GPP and $R_e$ from 1994 to 2003 depended on annual mean air temperature and total radiation but not on precipitation. Other deficiencies of CLM3.5-DGVM have been discussed.