• Journal of Radiation Protection and Research
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• v.37 no.2
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• pp.90-95
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• 2012

A radio-tracer experiment was performed in a greenhouse to investigate the effectiveness of the simultaneous application of K and Ca as a countermeasure for reducing the radiocaesium and radiostrontium uptake by rice. Paddy soil (loam of pH 6.5) in soil boxes was spiked with $^{137}Cs$ and $^{85}Sr$, and treated with K and Ca in the forms of KCl and $Ca(OH)_2$, respectively, at agrochemical grades before transplanting. For the seeds of the control plants, soil-to-plant transfer factors (TF, $m^2\;kg^{-1}-dry$) of $^{137}Cs$ and $^{85}Sr$ were $7.4{\times}10^{-5}$ and $2.1{\times}10^{-4}$, respectively, whereas the corresponding values for the straws were $2.6{\times}10^{-4}$ and $2.2{\times}10^{-2}$, respectively. The TF values of $^{137}Cs$ and $^{85}Sr$ kept decreasing as the level of the simultaneous application of K and Ca (K/Ca, $g\;m^{-2}$) increased up to 33.6/322 and 48.0/460, respectively. The maximum rate of the decrease was around 60% for both radionuclides. Nearly 60% reduction in the TF value of $^{85}Sr$ was observed even at the dosage of 33.6/322, which was considered the optimum dosage based on crop productivity as well as reduction in the radiocaesium and radiostrontium uptake by rice. The optimum dosage may depend on various factors so further experiments need to be made for many different conditions.

• The Korean Journal of Malacology
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• v.18 no.2
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• pp.77-82
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• 2002

This study was performed to find out the optimal kind of additive and concentration of ethylene glycol (EG) as the cryoprotectant on the D-shaped larvae of arkshell, Scapharca broughtonii. The larvae in straws was carried in the programed freezer set uo at 0$^{\circ}C$, frozen to -12$^{\circ}C$ by the freezing rate of -1$^{\circ}C$/min, held for 10 minutes, seeded at -12$^{\circ}C$, finally refrozen to -35$^{\circ}C$ by the freezing rate of -1$^{\circ}C$/min and then directly plunged into liquid nitrogen. The survival of larvae frozen in 1.0 M and 2.0 M ethylene glycol added with 0.5 M sucrose were high (50.5 ${\pm}$ 1.3% and 51.9 ${\pm}$ 1.7%, respectively) in the early D-shaped larvae cryopreserved in 1 M and 2 M ethylene glycol diluted with 0.2 M and 0.5 M fructose, glucose and sucrose. In the late D-shaped larvae were cryopreserved according to five concentrations of ethylene glycol added with 0.5 M sucrose, the survival of larvae frozen in 2.0 M ethylene glycol was the highest as 51.9 ${\pm}$ 1.7%. The morphological differences in cells between unfrozen and frozen-thawed D-shaped larvae were not found by the scanning and transmission electron microscopy.

• Journal of Radiation Protection and Research
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• v.29 no.3
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• pp.165-172
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• 2004

Rice plants were exposed to $I_2$ vapor for 80 min at different growth stages in an exposure box to investigate the parameters concerning direct plant contamination. Deposition velocity $(m\;s^{-1})$ of the $I_2$ vapor for the straws was in the range of $1.4{\times}10^{-5}-1.3{\times}10^{-4}$ depending on the exposure time, being comparatively low during the earlier part of the plant growth. Ear deposition velocity was in the range of $2.5{\times}10^{-5}-6.7{\times}10^{-5}$. Whole-plant deposition velocity was in the range of $1.4{\times}10^{-5}-1.8{\times}10^{-4}$ with the highest from the exposure performed on Aug. 18 (7 d after the start of heading). The time-dependent variation generally decreased when the deposition velocity was normalized to the biomass density No noteworthy tendency in the deposition velocity was observed with regard to the temperature, sunlight and humidity. Translocation factor for the hulled seeds was $3.3{\times}10^{-5}-4.7{\times}10^{-4}$ with the highest from the Aug. 23 exposure. It was found that a leaf deposition even before the ear emergence resulted in a considerable seed translocation.

• The Journal of Engineering Geology
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• v.25 no.4
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• pp.473-484
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• 2015

Geophysical exploration using electric resistivity, ground penetrating radar (GPR), and impedance high-frequency (ZHF) surveys was conducted in Gujwa-eup, Jeju City, Jeju Island, an island in the Korea Strait, to confirm the existence of new caves near known caves. The exploration revealed a number of anomaly zones, presumed to be caves; 27 sites at suitable locations and depth ranges were selected for drilling and further surveys. However, contrary to predictions, most of the anomaly zones were clinker layers or paleosols intercalated with lavas. Only five boreholes intersected caves. The clinker layers and paleosols were possibly detected as anomalies owing to their different physical properties from the other rocks. Two of the five cave-finding boreholes penetrated Yongcheon Cave; a new cave was found at the other. The two boreholes that penetrated Yongcheon Cave were drilled in areas where the cave has not been previously reported, and thus helped correct an error in the cave distribution map. The cave newly discovered in this boring exploration is 180 m long, and it is connected to the upstream part of Dangcheomul Cave (110 m). The cave contains well-developed lava helictites, lava levees, and ropy structures; carbonate speleothems such as soda straws, stalagmites, columns, and curtain shawls are also well preserved. Notably, the unique shape of the carbonate speleothems is attributed to their growth in relation to the cavern water that flowed into the cave along plant roots.

• Journal of Embryo Transfer
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• v.29 no.4
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• pp.397-401
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• 2014

The boar sperm has more lipid droplets and specialty of seminal plasma compared with other species, causing difficulties of freezing sperm and decreases for the utilization of frozen semen into the artificial insemination. However, several studies reported significant results for the recovery of sperm motility and reproductive by addition of cryoprotectants and seminal plasma after thawing. This study was designed to investigate the effects of supplementation of trehalose or glycerol in the LEY (lactose and egg yolk in BTS) solution for the conventional freezing and vitrification process. Two boars aged 16 months were used to collect semen for 2 times in a week. The samples were allotted to 3 freezing solutions (LEY + glycerol 10.5% + OEP 1.5%, LEY + trehalose 1M + OEP 1.5%, and sucrose 1.5M + trehalose 1 M + OEP 1.5%) after centrifugation at 800 g for 10 minutes. Semen was equilibrated in freezing solutions for 10 minutes and injected into plastic straws with 2~3 air bubbles to minimize freezing damages. Vitrification was performed to locate sperm in 5 cm above $LN_2$ for 5 minutes, and the conventional freezing was conducted with an automatic freezer. Motility and survival rates were measured by CASA (Computer assisted sperm an alyzing system) and FITC (Fluorescein isothiocyanate), respectively after thawing semen at $50^{\circ}C$ for 12 seconds. The results were analyzed by ANOVA with STATVIEW statistical program. The vitrificatioin solution (LEY + 10.5% glycerol + 1.5% OEP) presented higher motility (20.9%) than other solutions while the solution (LEY + 1M trehalose + 1.5% OEP) showed the lowest (motility : 5.2%). However, survival rates of vitrified sperms detected by FITC showed 1~4% live sperms in almost of dead sperms at all vitrification solutions' groups, but survival rate of freezing solution of LEY + 1M trehalose + 1.5% OEP LEY and LEY + 10.5% glycerol + 1.5% OEP were showed 49%, and 79%, respectively. There were differences (P<0.05) survival rate of conventional freezing in LEY + 10.5% glycerol + 1.5% OEP and LEY + 1M trehalose + 1.5% OEP and the remaining showed no differences. The results suggested that vitrified boar semen was not enough to be utilized for the artificial insemination, but it showed possibility to utilize for ICSI and conventional freezing with glycerol would be useful method for artificial insemination in pig while we choose the outstanding semen against tolerance to freezing damages.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.290-297
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• 2013

This study was carried out to investigate the effects of a by-product feed-based silage (BF silage) feeding on behavior patterns of growing Hanwoo steers. A total of 10 Hanwoo steers (11 months old, 302kg of body weight) were assigned to 2 dietary treatments: the control (concentrate mix + free access to rice straw), and the treatment (concentrate mix + free access to BF silage). The behavior patterns were observed for 48 hours. The intakes of dry matter (DM) and neutral detergent fiber (NDF) of the treatment group were higher than those of the control group. Eating time, ruminating time and resting time were not different between the control and treatment. But, the intake time per kg DM was higher for the control than treatment. The number of bolus, total chewing frequency, number of ruminating per bolus and number of bolus per minute were not different between the control and treatment. But the chewing frequency per bolus was higher in the treatment than control (p<0.05), and feed value index was lower in treatment than control (p<0.05). Frequencies of drinking and defecating were not different between the two groups, but the frequency of urinating was higher for the treatment (p<0.05) than control. Eating rate, ruminating efficiency and chewing efficiency were much higher in the treatment group than control (p<0.05). These results indicate that the replacement of conventional rice straws with the BF silage (physically effective NDF, about 25%) did not affect the ruminating behaviors of Hanwoo steers significantly.

• Animal Bioscience
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• v.34 no.12
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• pp.1940-1950
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• 2021

Objective: The objective of this study was to explore the effects of maize straw treated with calcium oxide (CaO) and various moisture, on the composition and molecular structure of the fiber, and gas production by fermentation in an in vitro rumen environment. Methods: The experiment used 4×3 Factorial treatment. Maize straws were treated with 4 concentrations of CaO (0%, 3%, 5%, and 7% of dry straw weight) and 3 moisture contents (40%, 50%, and 60%). Scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray fluorescence spectroscopy were employed to measure the surface texture, secondary molecular structure of carbohydrate, and calcium (Ca) content of the maize straw, respectively. The correlation of secondary molecular structures and fiber components of maize straw were analyzed by CORR procedure of SAS 9.2. In vitro rumen fermentation was performed for 6, 12, 24, 48, and 72 h to measure gas production. Results: Overall, the moisture factor had no obvious effect on the experimental results. Neutral detergent fiber (NDF), acid detergent fiber, acid detergent lignin, hemicellulose and cellulose contents decreased (p<0.05) with increasing concentrations of CaO treatment. Surface and secondary molecular structure of maize straw were affected by various CaO and moisture treatments. NDF had positive correlation (p<0.01) with Cell-H (H, height), Cell-A (A, area), CHO-2-H. Hemicellulose had positive correlation (p<0.01) with Lignin-H, Lignin-A, Cell-H, Cell-A. Ca content of maize straw increased as the concentration of CaO was increased (p<0.01). Gas production was highest in the group treated with 7% CaO. Conclusion: CaO can adhere to the surface of the maize straw, and then improve the digestibility of the maize straw in ruminants by modifying the structure of lignocellulose and facilitating the maize straw for microbial degradation.

• Korean Journal of Poultry Science
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• v.45 no.4
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• pp.237-244
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• 2018

In this study, to increase the survival rate of frozen/thaw rooster semen, standard protocols of semen thawing procedures were tested by computer-assisted sperm assay (CASA). We tested 4 different thawing protocols for frozen semen, $5^{\circ}C$ for 2 min, $35^{\circ}C$ for 30 s, $54^{\circ}C$ for 13 s, and $70^{\circ}C$ for 7 s. The pooled semen from 5 to 8 Ogye rooster line was diluted in the HS-1 diluent and frozen in 8% methylacetamide (MA) in liquid nitrogen vapors. To determine standard thawing method, straws were plunged into different temperatures and times. The resulting motilities were recorded by the CASA system. The results of this study showed that the best viability of the spermatozoa was shown by exposure at $5^{\circ}C$ for 2 min. Moreover, the longevity test of thawed sperm at $5^{\circ}C$ for 2 min also supported the higher viability under low temperature preservation of $17^{\circ}C$ for 1 hr. Further research is needed to increase the motility of thawed rooster semen for field application. In addition, the in vivo tests for different rooster lines are also needed for the establishment of avian genetic resource bank.

• Conservation Science in Museum
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• v.29
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• pp.153-162
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• 2023

Clay figure of Baekje, produced by forming and molding various shapes using clay, are mainly excavated from temple sites and provide essential information for studying the Buddhist art of Baekje. Research on clay figures of Baekje primarily focuses on the characteristics of Baekje-era temples in which such figures are excavated, as well as the role and production techniques of clay figures, by comparing regional and morphological characteristics. In particular, research on the manufacturing method of clay figures is mainly carried out by visual observation, whereas precise scientific analysis is required to understand production techniques and characteristics of raw materials in greater detail. In this study, to confirm such production techniques and material characteristics, computed tomography (CT) scans were conducted on the Clay Bodhisattva excavated from the Neungsan-ri Temple site in Buyeo. As a result, it was found that the Clay Bodhisattva was made using a cylindrical core of fine clay, tied together with several thin branches or reeds with straws. The clay used in the figure bore traces indicating the presence of herbaceous plants, which increase adhesion between clay and prevent cracks in the contraction process. On the other hand, the density of the fine clay differs on the inside and outside of the clay figure. Based on this, it is presumed that the clay was applied around the cylindrical core to shape the Clay Bodhisattva. The clay was reapplied on top of the figure to express the detailed shape and pattern.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.1
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• pp.104-109
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• 2010

Hydro-thermal liquefaction technology for rapeseed straws was investigated the biomass conversion rate with different catalysts and reaction temperatures. NaOH and KOH were used for catalysts, and the reaction temperature were ranged from 180 to $320^{\circ}C$ at every $20^{\circ}C$ of intervals for 10 minutes. The reaction was carried out in a 5,000 mL liquefaction system with dispenser and external electrical furnace. Raw materials (160g), 2,000 mL of distilled water and 10% (wt/wt) of catalyst to plant residue were fed into the reactor. It was observed that the maximum crude oil yield was about 36% at temperature range, $260{\sim}280^{\circ}C$ with KOH and at $300^{\circ}C$ with NaOH, respectively. It was observed that the more calorific values of crude oil, the higher reaction temperature with KOH, but it had the reverse pattern in NaOH.