• Bulletin of the Korean Chemical Society
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• v.26 no.10
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• pp.1597-1599
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• 2005

• Journal of Life Science
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• v.22 no.6
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• pp.794-798
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• 2012

Paratuberculosis (Johne's disease), a chronic wasting disease caused by Mycobacterium avium subspecies paratuberculosis (MAP), is a major cause of economic loss in the cattle industry. In Korea, national monitoring of breeding stock for MAP has been implemented. In this study, we report the results of serological testing to determine the prevalence of MAP in breeding stock of Korean native and dairy cattle during 2008 and 2009. A total of 3,927 serum samples were submitted (3,692 Korean native cattle and 235 dairy cattle) to Animal Disease Diagnostic Division, Animal, Plant and Fisheries Quarantine and Inspection Agency. The samples were classified into four different age groups for MAP; group 1 (${\leq}2$ year, n = 1,509), group 2 (>2 years to ${\leq}3$ years, n = 486), group 3 (>3 years to ${\leq}4$ years, n = 441), and group 4 (>4 years, n = 1,491). Overall seroprevalence of MAP in this study was 0.5% (21/3,927), which was much lower than that of conventional cattle (1.2-16.4%) in Korea. Also, the seroprevalence was determined by age groups: three of group 1 (0.2%), two of group 2 (0.4%), three of group 3 (0.7%), and 13 of group 4 (0.9%) were seropositive for MAP, respectively. Although seropositive samples were found in all age groups, the seroprevalence tended to increase with age. Our study showed that the seroprevalence of MAP in pure-bred breeding dairy cattle (0%) was lower than that in pure-bred breeding Korean native cattle (0.6%).

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.1092-1098
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• 2012

Aroma compounds in sun-dried salt according to saltern material and packaging box were extracted by the headspace and were isolated by using GC-MS. These compounds were identified including ketones, heterocyclic compounds and six other compounds. Major aroma compounds in salts were identified as 4-methyl-2-pentanone, 5-methyl-3-hexanone, 4-methyl-3-penten-2-one, 2-hexanol, benzothiazole, 2,4-bis(1,1-dimethylethyl)-phenol, and 1,3,5-tri-tert-butyl benzene. However, we found no significant differences according to the saltern materials in three salts. Salts stored in Chamaceyparis obtusa (Sieb. et Zucc.) had more diverse aroma profiling than those in Pinus densiflora and Paulownia coreana. We consider that it need to research the development of high value added products for new aromatic salt.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2073-2076
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• 2010

• Journal of Animal Science and Technology
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• v.61 no.4
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• pp.225-233
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• 2019

The aim of this study was to produce porcine tetraploid (4N) parthenogenetic embryos using various methods and evaluate their developmental potential. In method 1 (M1), porcine 4N parthenogenetic embryos were obtained by inhibiting extrusion of both first (PB1) and second (PB2) polar bodies; in methods 2 (M2) and 3 (M3), 4N parthenogenetic embryos were obtained by electrofusion of 2-cell stage diploid parthenogenetic embryos derived from inhibition of PB2 or PB1 extrusion, respectively. We found no differences in the rates of cleavage or blastocyst formation or the proportion of 4N embryos among M1, M2, and M3 groups. The different methods also did not influence apoptosis rates (number of TUNEL-positive cells/number of total cells) or expression levels of apoptosis-related BAX and BCL2L1 genes. However, total cell and EdU (5-ethynyl-2'-deoxyuridine)-positive cell numbers in 4N parthenogenetic blastocysts derived from M1 were higher (p < 0.05) than those for M2 and M3 groups. Our results suggest that, although porcine 4N parthenogenetic embryos could be produced by a variety of methods, inhibition of PB1 and PB2 extrusion (M1) is superior to electrofusion of 2-cell stage diploid parthenogenetic embryos derived from inhibition of PB2 (M2) or PB1 (M3) extrusion.

• Journal of the Korean Ceramic Society
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• v.37 no.10
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• pp.968-974
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• 2000

Nb$_2$O$_{5}$와 MnO 첨가에 따른 Pb$_{0.6}$Sr$_{0.4}$TiO$_3$반도체 세라믹의 미세구조와 전기적 특성은 유전특성, I(current)-V(voltage) 측정, 그리고 복소 임피던스 측정 등을 이용하여 고찰하였다. Nb 도핑량이 0.4 mol% 이하인 경우 Nb 도핑량에 따라 전도성과 입성장은 증가되었으나 그 이상의 도핑량에서는 Sr이나 Pb 공공의 생성으로 인하여 전도성이 감소되고 입성장도 억제되는 것을 관찰할 수 있었다. 0.4 mol% Nb-doped Pb$_{0.6}$Sr$_{0.4}$TiO$_3$에 0.01 mol% MnO를 첨가한 경우 비저항비($ ho$$_{max}$/$\rho$/min/)가 $10^2$에서 $10^4$으로 크게 향상되었다. 그리고 전이 온도 주변에서 여러 개의 변곡점을 지니는 비옴성 거동이 발견되었다. 이와 같은 현상은 입계에 존재하는 Mn 이온이 부분적으로 편석되어 표면 전하의 보상 효과에 영향을 미치는 것이라고 사료된다.

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.715-720
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• 2004

Amineterminated, ethylenediamine core polyamidoamine starburst dendrimers of generation 2 (G2), generation 4 (G4) and generation 6 (G6) have been successfully surface-modified via an amide coupling reaction with 4-ethyl, 4'-(3-propionic) bipyridinium cation and the electrochemical behavior of the resulting dendrimers were investigated in aqueous potassium chloride electrolyte solutions. The 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide-mediated reaction resulted in 25-39% end-group functionalization. The water-soluble 4-ethyl, 4'-(3-propylamide) bipyridinium dibromide dendrimers (G2-V2+, G4-V2+ and G6-V2+) were characterized by $^1H$ NMR and UV-Vis spectroscopic methods. The cyclic voltammetric and chronoamperometric experiments were performed to determine the diffusion coefficient and the number of electrons transferred in the process of the first reduction of the viologen-functionalized dendrimers. Adsorption of viologen-functionalized dendrimers at electrode surface was evidenced in the voltammograms. Experimentally determined diffusion coefficients were in good agreement with the values expected from the Stokes-Einstein relation, while the number of electrons transferred concurred with the extent of functionalization determined by $^1H$ NMR and UV-Vis spectra.

• Journal of the Korean Institute of Rural Architecture
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• v.5 no.2
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• pp.10-19
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• 2003

The purpose of this study was to analyze the formation and change of road-block-lot of the old inner city in cheongju The result of this study are as follows; (I)Among others a system roads of in around the old castle in cheongju city is most of feature north and south direction of road. Lot system is organic relations of north and south direction of road. Therefore, urban tissue in around the old castle in cheongju city is established order road system keep on the change of expansion urban tissue. (2) Block type classified into non-division, 2division and over 3division. (3) The square block remains mostly in Cheongju old castle, two-division block was around south of castle. And block of the grid-form street system divided into over 3 division. Through the guideline about characteristic of block type, residential area should be developed as a characteristics area in the urban area.

• Journal of Mushroom
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• v.15 no.4
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• pp.269-272
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• 2017

We developed a log-burying cultivation technique for Grifola frondosa using oak logs and surveyed its annual yield characteristics. As a result of G. frondosa log cultivation, the harvesting period of the 'Yipsae1ho' cultivar was delayed by approximately 10-15 days compared to that of the Dabak cultivar, and the fruit color of the 'Yipsae1ho' cultivar was dark brown, while that of the 'Dabak' cultivar was grayish brown. Yield of the 'Yipsae1ho' cultivar was $16.0 kg/m^2$ in the first year, $15.4kg/m^2$ in the second year, $9.5 kg/m^2$ in the third year, $4.6 kg/m^2$ in the fourth year, and $4.6kg/m^2$ in the fifth year, while yield of the 'Dabak' cultivar was $12.3kg/m^2$ in the first year, $11.5kg/m^2$ in the second year, $12.7kg/m^2$ in the third year, $6.2 kg/m^2$ in the fourth year, and $8.2kg/m^2$ in the fifth year. Total yield of the 'Yipsae1ho' cultivar ($50.0 kg/m^2$) was slightly lower than that of the 'Dabak' cultivar ($50.8kg/m^2$). The optimum period for log-burying cultivation of Grifola frondosa is estimated to be 3 years.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.947-952
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• 2015

The aim of this study was to evaluate the effects of grape juice on colon carcinogenesis induced by azoxymethane (AOM) and expression of NF-kB, iNOS and TNF-${\alpha}$. Methods: Forty male Wistar rats were divided into 7 groups: G1, control; G2, 15 mg/kg AOM; G3, 1% grape juice 2 weeks before AOM; G4, 2% grape juice 2 weeks before AOM; G5, 1% grape juice 4 weeks after AOM; G6, 2% grape juice 4 weeks after AOM; G7, 2% grape juice without AOM. Histological changes and aberrant crypt foci (ACF) were studied, while RNA expression of NF-kB, TNF- and iNOS was evaluated by qPCR. Results: The number of ACF was higher in G2, and G4 presented a smaller number of crypts per focus than G5 (p=0.009) and G6. Small ACF (1-3) were more frequent in G4 compared to G2, G5 and G6 (p=0.009, p=0.009 and p=0.041, respectively). RNA expression of NF-kB was lower in G3 and G4 compared to G2 (p=0.004 and p=0.002, respectively). A positive correlation was observed between TNF-${\alpha}$ and NF-kB gene expression (p=0.002). In conclusion, the administration of 2% grape juice before AOM reduced the crypt multiplicity, attenuating carcinogenesis. Lower expression of NF-kB was observed in animals exposed to grape juice for a longer period of time, regardless of concentration.