• Journal of Mushroom
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• v.10 no.4
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• pp.151-159
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• 2012

The button mushroom (Agaricus bisporus) is one of the most widely cultivated important edible mushroom species. In the breeding of new button mushroom, 'Seolgang' was developed by crossing two monokaryons 'CM020913-27' and 'SSU423-31'. Because of the secondarily homothallism, only a small percentage of the basidia produce 3 or 4 spores, which are mostly haploid (n) and do not fruit. Single spore cultures derived from these types of spores produce a vegetative mycelium that also contain a variable number of genetically identical nuclei per cell called monokaryon. The lack of clamp connections between monokaryon and dikaryon required a series of mycelial culture and fruiting test. After crossing, hybrids were cultivated on a small scale and on a commercial scale at a farm. For this, the spawn was made by a commercial spawn producer and the spawned compost by a commercial compost producer. Mycelial growth of 'Seolgang' on CDA was better at $20^{\circ}C$ and $25^{\circ}C$ when it was compared with that of '505 Ho'. The mature cap shape of new strain 'Seolgang' is oblate spheroid and the immature cap shape is round to oblate spheroid. The cap diameter was 41.2 mm on average. In comparison with white strain '505 Ho', the strain had a yield that was 9% higher. It produced fruiting bodies which had a higher weight on average per fruiting body and were 19% firmer with a good shelf life. Days of fruiting body were 3-4 days later than those of '505 Ho'. The physical characteristics such as elasticity, chewiness, adhesiveness were better than that of '505 Ho'. Genetic analysis of the new strain 'Seolgang' showed different profiles compared to '505 Ho', CM02913-27, SSU413-31, when RAPD primers A02 and O04 were used.

• Environmental and Resource Economics Review
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• v.16 no.2
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• pp.379-409
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• 2007

Korea's energy sector was one of policy sectors that exhibited the classical bureaucratic governance of an administrative state. Under the regime, government monopolized the policy-making process and controled the market and the civil society. It not only provided energy goods and services directly through public enterprises but also dominated the market activities through public regulations. However, during 1993~2002, stringent reformation efforts were made to transform the governance regime from the past bureaucratic model to the market model, by way of privatization of public enterprises and deregulation. The ideology behind the reformation based on the shared recognition that the market and spontaneous order thereof is the better apparatus than the government and artificial order thereof in solving social problems mote efficiently. From the year of 2003, another round of reformation efforts have been promoted to introduce the participatory governance model, through institutionalization of channels for the wider participation of civil society into the energy policy-making process. This reformation efforts respond to; first, the increasing criticism from the civil society on the closedness of energy policy process and the higher probability of policy failures thereof, and second, the recognition that the self-organizing nature of an open policy process is the better mechanism for evolutionary problem-solving.

• Applied Microscopy
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• v.36 no.4
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• pp.271-277
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• 2006

Mast cells (MCs) are granulated cells that play a pivotal role in allergic reaction and inflammation. The granules of mast cells are known to be rich in zinc (Zn). Male Sprague-Dawley rats were used. We injected $200{\mu}L$ of complete Freund's adjuvant (CFA) subcutaneously in the dorsal aspect of one hindpaw Finally, zinc selenium autometallography(AMG) was done by Danscher's method. The present study showed the ultrastructures of zinc-containing mast cells found in inflammatory area following an complete freund's adjuvant (CFA) inoculation into the rat hindpaw. At light microscopic level, mast cells were round or oval, at average $12{\mu}m$ in diameter, with many filopodia extending from the cell surface. Because the rather small and spherical nucleus was centrally placed; it was frequently obscured by the cytoplasmic granules, it sometimes could not be seen. Mast cells were distributed chiefly in the vicinity of small blood vessels. In most preparation many mast cells were ruptured and their granules escaped into the surrounding tissue. In electron micrographs, The secretory granules were at average $0.5{\mu}m$ in diameter and were limited by a membrane. The cell surface contained numerous microvilli and folds. Their interior was heterogenous in appearance. The nucleus was surrounded by large numbers of prominent vesicels and a well developed Golgi apparatus, but scant endoplasmic reticulum.

• Journal of the Korean Society of Food Culture
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• v.16 no.4
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• pp.310-315
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• 2001

Flavor modifing effects of ${\beta}-cyclodextrin$ on the flavor of Chungkookjang(Korean traditional fermented bean paste) were investigated with varied substitution levels of 10, 20, and 30%. The 20% substituted sample groups showed significantly lower amount of protein and ash contents compared to those of control. The L value of brightness had significantly the largest value of 53.99 with 30% substituted sample group, and lower a and b values. Internal structures of control group observed using the scanning electronic microscope, had irregular round type shape with viscous materials, and they had tendencies to be less rough and organized making even and ordered internal cell structures as the substituted levels were increased. Results of sensory characteristics showed significantly lower off-odor and salty flavor with the 20% substituted sample groups compared to those of control. Results of this study showed the possibilities of flavor moderating effects of ${\beta}-cyclodextrin$ when it was used as one of the flavor modifier of the Chungkookjang. Future studies of finding the optimum level of substitution is further required.

• Restorative Dentistry and Endodontics
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• v.27 no.2
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• pp.113-121
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• 2002

Conventional intraoral radiography continues to be the most widely used image modality for the diagnosis of dental caries. But, conventional intraoral radiography has several shortcomings, including the difficulty of exposing and processing intraoral film of consistently acceptable quality. In addition, radiographic retaking that was the result of processing errors, may result in increased discomfort and radiation dose to the patient. Recently, various digital radiographies substitute for conventional intraoral radiography to overcome these disadvantages. The advantages of digital radiography are numerous. One of advantages Is the elimination of processing errors. In addition, the radiation dose for digital system is approximately 20% to 25% of that required for conventional intraoral radiography Another potential advantage of digital imaging is the ability to perform image quality enhancements such as contrast and density modulation, which may increase diagnostic accuracy. The purpose of this study was to compare the diagnostic ability of artificial proximal defects to conventional intraoral radiography, direct digital image(CDX2000HQ$^{\circledR}$) and indirect digital image(Digora$^{\circledR}$). Artificial defects were made in proximal surfaces of 60 extracted human molars using #1/2, #1, #2 round bur. Five dentists assessed proximal defects on conventional intraoral radiography, direct digital image(CDX2000HQ$^{\circledR}$) and indirect digital image(Digora$^{\circledR}$). ROC(Receiver Operating Characteristic) analysis and Two-way ANOVA test were used for the evaluation of detectability, and following results were acquired. 1. The mean ROC area of conventional intraoral radiography, direct digital image(CDX2000HQ$^{\circledR}$) and indirect digital Image(Digora$^{\circledR}$) were 0.6766, 0.7538, 0.6791(Grade I), 0.7176, 0.7594, 0.7361(Grade II), and 0.7449, 0.7608, 0.7414(Grade III), respectively. 2. Diagnostic ability of direct digital image was higher than other image modalities. But, there was no statistically significant difference among other imaging modalities for Grade I, II, III lesion(p>0.05). In conclusion, when direct and indirect digital system are comparable with conventional intraoral radiography. these systems may be considered an alternative of conventional intraoral radiography for the diagnosis of proximal surface caries.

• Korean Journal of Environment and Ecology
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• v.31 no.5
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• pp.455-460
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• 2017

Since a new (unrecorded) species was reported in 2016, a total of four sea snake species are currently listed in Korean waters. Although the possibility of year-round inhabitation of sea snakes in Korean waters has increased due to climate change, the related studies are scarce because of the lack of human resources and available equipment. We placed posters and banners requesting voluntary information on sea snakes in coastal regions and Jeju Island to obtain information on sea snake distributions in the coasts of South Korea and possible specimens through volunteer activities. As a result, we received total 45 reliable reports, including photographs or video, between March 2013 and December 2016. Eighteen reports on three sea snake species and thirteen capture cases of two species were submitted from Jeju Island and southern coastal regions of Korea mostly between August and November. There were twenty-seven false reports including seven cases of terrestrial snakes, eighteen fishes, and one each of invertebrate and inanimate material. Based on the results, we proposed the effective way of sea snake surveys using volunteers.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.720-730
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• 1997

This study was performed to observe the histopathological response to the bonding resin directly applied on the remaining pulp tissues. 40 teeth from 3 adult dogs were pulpotomized with a sterile round bur and sharp excarvater. In the control group, $Ca(OH)_2$ powder was applied on the pulp tissue and the cavities were sealed with IRM cement. In the experimental group 1, Superbond C&B was applied on the remaining pulp and the cavities conditioned with 10-3 solution were filled with the mixture of the MMA liquid, PMMA powder and Catalyst. Multi-purpose adhesive was used on the remaining pulp tissue in the experimental group 2 and Z-100 was filled in the cavities. In the experimental group 3, Clearfil photobond applied and directly photo-cured on the pulp tissue, then the cavities were treated with CA agent (10% citric acid and 20% $CaCl_2$ aqueous solution) for 20 seconds, washed and applied with Clearfil photobond then filled with Protect liner. The experimental animals were sacrified at the 1st, 2nd, and 4th week. The specimens were routinely processed and stained with H-E for light microscopic observation. The results were as followed : 1. In the experimental group 1, the number and characteristics of the dentin bridge formation case was similar to those in the control group and less cases were observed in the experimental group 2 and 3 than experimental group 3. The inflammatory response in experimental group 1 was less than that in the control group at 1st week but there had been little difference at between 2nd and 4th week. 2. The number of the dentin bridge in experimental group 2 was less than that in control group and experimental group 1. The inflammatory response of the experimental group 1 was similar to that of experimental group 1 but less than that of the control group. A number of bleeding and vascular congestion were observed. The least inflammatory response was seen in the experimental group 2 among all groups. 3. In the experimental group 3, one case of the dentin bridge formation was observed and that was the same as that in the experimental group 2 but smaller than that of the control and experimental group 1. The inflammatory response of the experimental group 3 was least at the 1st week and most at the 4th week in the all group.

• Korean Journal of Veterinary Research
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• v.37 no.1
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• pp.79-86
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• 1997

This study was designed to investigate the effects of superovulation on the growing and mature follicles following gonadotrophin treatments in mature rat by immunohistochemical methods. Eighteen mature rats (Sprague-Duwely, 190~230gm) were randomly alloted into 3 groups. One group was control group, another FSH-treated group was injected intramuscularly with 0.5 units of follicular stimulating hormone(FSH) / rat, and third PMS and HCG-treated group was injected intramuscularly with 20~25IU of pregnant mare serum(PMS) / rat and then at the 48 hrs later, with 20~25IU of human chorionic gonadotropin(HCG) / rat. Half the number of rats were administrated intraperitoneally with bromodeoxyuridine(Brdur, 0.2mg/gm BW once) at 2 hours before exanguination and the remainder of rats were sacrified without Brdur administration. The investigation by immunohistochemical methods using paraffin sections of ovaries was performed by using anti-Brdur antibody and PCNA(proliferating cell nuclear antigen) antibody for labeling proliferating cells in follicles. In immunohistochemical findings, follicles squeezed by peripheral corpus luteum or follicles large follicles with loosly and irregularly distributed granulosa cells and although with compacted granulosa cells, middle follicles with dilated round or oval follicular antrum were confirmed as atretic follicles. The proportions of atretic follicles in control group were 29.8%, 21.7% and 14.2% respectivley at large, middle and small follicles and mean proportions of these all 3 grade follicles were 26.7%. The proportions of atretic follicles in FSH-treated group were 35.4%, 24.9% and 10.4% respectively at large, middle and small follicles and mean proportions of these all 3 grade follicles were 28.1%. The proportions of atretic follicles in PMS and HCG-treated group were 44.7%, 24.0% and 12.7% respectively at large, middle and small follicles, and mean proportions of these all 3 grade follicles were 29.7%. The above findings reveal that the group with higher proportion of atretic follicles were ordered as large, middle and small follicles in size, and these proportions were increased in hormone treated two groups with more number of more growing and mature follicles when compared with control group.

• Restorative Dentistry and Endodontics
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• v.30 no.2
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• pp.95-101
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• 2005

The aim of this study was to evaluate the microleakage of teeth according to root canal preparation with & without apical enlargement in various size of apical foramen. 60 extracted one canal roots were cross-cutted at 5 mm from root apex and divided into two groups according to their apical foramen size of large (L) and small (S). Each group was subdivided into two groups accordance with their cross-sectional configuration at 5 mm from apex, round (R) and ovoid (O); SR Group, SO Group LR Group, LO Group. Each group was shaped in .02 taper by Quantec series Nickel-Titanium (NiTi) rotary file, obturated by lateral condensation method. Leakage was measured using a fluid transport model under 40 $cmH_2O$ pressure. After the leakage test, blocks which had showed the leakage retreated with .04 taper and ,06 taper and evaluated the degree of fluid filtration in each group. The data was analysed statistically using chi-square test and fisher's exact test. The results obtained were as follows : 1. Significant difference in leakage was found in groups which had different apical foramen size in .02 taper instrumentation (p < 0.05), but not in .04 taper instrumentation (p > 0.05) 2. The difference in microleakage according to the shape of canal was not evident at 5 mm from apex (p > 0.05). 3. There was correlation between .02 taper instrumentation and .04 taper instrumentation in LR group, LO group (p < 0.05).

• Restorative Dentistry and Endodontics
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• v.25 no.3
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• pp.435-445
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• 2000

The purpose of this study was to compare the leakage of four different obturation techniques in conjunction with immediate apical barrier of ${\beta}$-tricalcium phosphate(TCP) in teeth with open apex. Eighty single-rooted human premolar teeth were prepared and sectioned horizontally, so maximum diameter in apex was 4mm. Apical defects that were similar to open apex, were created with #1/2 round bur and SF104R bur. The apical foramen were opened to a size 80 file extended 3mm beyond the apex. The teeth were placed into the oasis block soaked saline to simulate periapical tissue often associated with pulpless teeth and received apical barriers consisting of TCP followed by obturation using lateral condensation technique, vertical condensation technique, continuous wave technique and thermoplasticized gutta-percha injection technique. Two unobturated teeth served as positive and negative controls. Teeth were immersed in resorcinol-formaldehyde resin for S days at $4^{\circ}C$, and the resin was allowed to polymerize completely for 4 days at room temperature. Teeth were then sectioned horizontally at 1.5mm(level 1), 2.5mm(level 2) and 3.5mm(level 3) from the apex, and examined under a stereomicroscope at ${\times}40$ magnification. The photographs were taken at ${\times}40$ magnification of the filling in each level and scanned. The leakage length in tooth/resin interface was measured at each of the three levels. Each ratio of leakage was obtained by calculating the ratio of the leakage length of canal wall infiltrated with resin to the total length of the canal and was analyzed statistically(One-way ANOVA and Scheffe test). The result were as follows : 1. At the level 1, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), but there was statistically significant(p<0.05). 2. At the level 2, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), and the most leakage in the continuous wave technique group(group 3). There was statistically significant difference between the thermoplasticized gutta-percha injection technique group and the continuous wave technique group(p<0.05). 3. At the level 3, there was the least leakage in the thermoplasticized gutta-percha injection technique group(group 4), but there were no statistically significant differences between other groups(p>0.05). These results suggest that thermoplasticized gutta-percha injection technique which had 1mm apical gutta-percha matrix after the formation of TCP apical barrier, can demonstrate favorable apical sealing.