• 한국식품조리과학회지
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• 제11권3호
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• pp.261-266
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• 1995

3 종류의 생선(광어, 새우, 굴) homogenate와 tryptic soy broth(TSB)에 Staphylococcus aureus와 Listeria monocytogenes를 접종하여 35$^{\circ}C$에서의 증식과 냉장(5$^{\circ}C$) 및 동결저장(-2$0^{\circ}C$) 하였을 때 각 세균의 거동을 조사하였다. S. aureus는 생선 homogenate와 액체배지 모두 35$^{\circ}C$에서 큰 차이없이 빠르게 증식하였다. 5$^{\circ}C$에 3주간 저장하였을 때 S. aureus는 1-1.6 log cycle 감소하였으나 -2$0^{\circ}C$에서는 6주간의 저장기간 동안 0.3-1.2 log cycle의 세균수 감소를 나타내었다. L. monocytogenes는 35$^{\circ}C$에서 광어 homogenate, 새우 homogenate와 TSB에서 증식이 빨랐으나 굴 homogenate에서는 유도기를 거친 후에 증식이 진행되었다. 5$^{\circ}C$에서 L. monocytogenes는 광어 homogenate, 새우 homogenate와 TSB에서 3주간 증식이 진행되어 세균수가 3.8-5 log cycle 증가하였으나 굴 homogenate에서는 2.2 log cycle의 증가에 불과하였다. -2$0^{\circ}C$에 6주간 저장하였을 때 L. monocytogenes의 세균수는 광어 homogenate, 새우 homogenate 및 TSB에서 1.5-1.8 log cycle 감소하였으나 굴 homogenate에서는 2.8 log cycle 감소하였다

• 한국식품조리과학회지
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• 제27권3호
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• pp.21-28
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• 2011

In this study, we analyzed flower tea activity against oral bacteria. Lagerstroemia indica, Paeonia suffruticosa and Hemerocallis fulva showed high extract yields. Bellis perennis, Punica granatum and Cercis chinensis showed the high rates of yield by ethanol extraction. Extract yield seemed to be related to the characteristics of the specimens rather than to the solvent. Streptococcus mutans, Streptococcus obrinus, Porphyromonas gingivalis and Prevotella intermedia were used to investigate extracts activity against bacteria; the former two cause dental caries and the latter two cause halitosis. Cornus officinalis, L. indica, P. granatum and P.s uffruticosa showed high antibacterial activities against S. mutans. In specimens extracted with ethanol, P. suffruticosa, Camellia sinensis, Camellia japonica L. and Rosa hybrida showed high antibacterial activities. L. indica, P. granatum and C. officinalis showed high antibacterial activities against S. sobrinus. C. officinalis, P. granatum, L. indica and P. suffruticosa showed high activities for specimens extracted with ethanol. The results show that the warm extracts of C. officinalis, L. indica and P. granatum may be effective to prevent dental caries. In particular, the ethanol-based extracts of C. officinalis, P. suffruticosa and C. sinensis were effective to prevent dental caries and thus may be highly marketable. Chrysanthemum zawadskii, R. hybrida, P. granatum, C. japonica L. and Zinnia elegans showed high antibacterial activity against P.gingivalis. R. hybrida showed the highest ethanol extract activity, followed by P. suffruticosa, P. granatum, C. japonica L. and L. indica. R. hybrida, P. granatum, C. morifolium and C. japonica showed high activity against Pr.intermedia in the order named. C. zawadskii, P. granatum, L. indica, C. japonica and A. princeps showed high ethanol extract activity. Thus, the warm extracts of R. hybrida, P. granatum and C. japonica may be helpful to reduce halitosis. In addition, the ethanol-based extracts of P. granatum, C. japonica and L. indica are expected to be highly marketable as mouthwashes.

• Toxicological Research
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• 제8권2호
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• pp.331-342
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• 1992

The chicken major histocompatibility complex (MHC), the B complex, is beginning to be analyzed at the DNA level. Inbred lines of chickens have been reported to possess 3~5 MHC class II genes. To further analyzed the molecular structure of the chicken MHC class II genes, cDNA clones coding for chicken MHC class II (B-L) ${\beta}$ chain molecules were isolated from chicken spleen and liver. Tissue-specific transcription of B-L ${\beta}$genes was studied by Northern blot analysis. A high level of expression was detected for spleen poly(A)$^+$ RNA whereas a faint signal was detected for liver poly(A)$^+$ RNA. Twenty-nine cDNA clones were isolated from the spleen and eight cDNA clones were isolated from the liver. Based on restriction maps, most clones could be clustered into one family of genes. Four cDNA clones were sequenced (S7, S10 and S19 from the spleen and L1, which was identical to S19, from the liver). Complete amino acid sequences of B-L ${\beta}$ chain molecules were predicated from the nucleotide sequences of the cDNA clones. Although both the nature and the location of the conserved residues were similar in chicken and mammalian sequences, some species-specific differences were found, suggesting that the structures of the B-L molecules are similar, but not identical to their mammalian counterparts.

• 생약학회지
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• 제4권2호
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• pp.67-70
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• 1973

In Peucedanum japonicum and Aster tataricus L. chlorogenic acid was identified by methods of P.P.C. and T.L.C. $L-Phenylalanine-U-^{14}C\;and\;sodium\;acetate-2-^{14}C$ were administered to Peucedanum japonicum, $L-Tyrosine-U-^{14}C$ to Aster tataricus and $caffeic\;acid-carboxyl-^{14}C\;and\;L-tyrosine-U-^{14}C$ to Fagopyrum esculentum $M_{OENCH}$. The incorporation of each compound into chlorogenic acid was compared. $L-Phenylalanine-U-^{14}C$ showed higher incorporation to chlorogenic acid than sodium $acetate-2-^{14}C$ in Peucedanum japonicum. $Caffeic{\;}acid-carboxyl-^{14}C$ was higher to chlorogenic acid than $L-tyrosine-U-^{14}C$ in Fagopyrum esculentum. $L-Tyrosine-U-^{14}C$ was comparatively low in Aster tataricus.

• 한국식품저장유통학회지
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• 제16권5호
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• pp.636-643
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• 2009

세척 당근에 E. coli O157:H7과 L. monocytogenes를 인위적으로 접종한 후 UV-C 조사 처리에 따른 저장 중 미생물수 변화를 조사하였다. 당근에 접종된 E. coli O157:H7과 L. monocytogenes의 초기 균수가 6-7 log CFU/mL가 되게하였고, 사용된 UV-C 조사선량은 1, 3, 5, $10\;kJ/m^2$이었으며 조사된 시료는 $4{\pm}1^{\circ}C$에서 8일 동안 저장하였다. UV-C 조사는 E. coli O157:H7과 L. monocytogenes의 미생물 수에 있어서 조사선량이 증가할수록 유의적으로(p<0.05) 감소하는 것을 나타냈다. 특히, $10\;kJ/m^2$ 처리구는 대조구와 비교하여 E. coli O157:H7과 L. monocytogenes의 미생물 수를 각각 2.35, 2.38 log CFU/g 감소시켰다. 품질 변화에서는 UV-C 조사 5, $10\;kJ/m^2$ 처리구가 저장 중 당근 표면 $L^*$ value의 급격한 증가와 $a^*$, $b^*$ value의 감소 및 백화현상을 유의적으로(p<0.05) 억제시켰다. 관능적 품질 평가는 5, $10\;kJ/m^2$ 처리구가 대조구에 비해 유의적으로(p<0.05) 높게 나타났다. 따라서 본 연구결과, UV-C 조사 처리는 세척 당근의 저장 중 미생물학적 안전성 확보와 품질유지 향상에 효과적인 것으로 판단된다.

• 한국미생물·생명공학회지
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• 제48권4호
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• pp.547-555
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• 2020

미세조류는 효율적으로 바이오매스를 증가시킬 수 있으며 유용한 생물학적 자원들을 축적할 수 있기 때문에 에너지 및 식품 생산 등 다양한 분야에서 유망한 자원으로써 주목받고 있다. 본 연구에서는 4종의 미세조류(Chlorella vulgaris, Mychonastes homosphaera, Coelastrella sp., Coelastrella vacuolata)를 선정하여 이들의 성장, CO2 동화, CO2 농도에 따른 미세조류의 지질 생성 특성을 분석하였다. 각 미세조류의 크기는 C. vulgaris가 가장 작았으며, M. homosphaera, C. vacuolata, Coelastrella sp. 순으로 큰 크기를 나타냈다. C. vulgaris는 다른 3종의 미세조류와 비교해서 크기가 가장 작으며 성장과 CO2 동화 속도가 가장 빠르게 나타났다. 또한, 초기 바이오매스가 증가함에 따라 CO2 동화 속도는 최대 9.62 mmol·day-1·l-1를 나타냈으며, 다른 3종의 미세조류(약 3 mmol·day-1·l-1)보다 3배 이상 높은 CO2 동화 속도를 보여주었다(p < 0.05). M. homosphaera를 제외하고 3종의 미세조류는 CO2 농도와 CO2 동화 비속도 사이에 양의 상관관계(positive correlation)를 나타냈다. 특히, C. vulgaris는 다른 3종의 미세조류와 비교해 더 높은 CO2 동화 비속도를 보여주었다(14.6 vs. ≤ 11.9 mmol·day-1·l-1). 4종의 미세조류는 CO2 농도가 증가함에 따라 지질 함량이 증가했으며 그 중에서 C. vulgaris는 최대 18 mg·l-1를 나타내 다른 3종의 미세조류(최대 12 mg·l-1)보다 최소 50% 이상 높은 지질 함량을 보여주었다. 4종의 미세조류 중 C. vulgaris가 효율적으로 CO2를 동화하며 다른 미세조류보다 높은 바이오매스와 지질 생산이 가능함을 시사한다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권1호
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• pp.90-96
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• 2008

We compared the effects of supplementing $L-lysine{\cdot}SO_4$ to L-lysine HCl on growth performance, nutrient digestibility and nitrogen retention in weaning pigs. A total of 96 crossbred pigs, weaned at $21{\pm}3$ days of age and with an average initial body weight (BW) $6.23{\pm}0.01kg$, were given one of 4 treatments, which translated into 6 replicates of 4 pigs in each pen. The animals were randomly assigned to four dietary treatments according to a randomized completely block design (RCBD) as follows: 1) control-no synthetic lysine, lysine deficient (0.80% total lysine); 2) L-C (= 0.2% L-lysine HCl); 3) K-L-S (= 0.332% $L-lysine{\cdot}SO_4$, A company); 4) C-L-S (= 0.332% $L-lysine{\cdot}SO_4$, B company). Diets were formulated with corn, soy bean meal, and corn gluten meal as the major ingredients, and all nutrients except the lysine met or exceeded NRC requirements (1998). The lysine content of supplemented synthetic lysine was the same in all treatment groups except the control. No clinical health problems associated with the dietary treatments were observed. During the entire experimental period, body weight, average daily gain (ADG) and feed efficiency (G:F ratio) increased (p<0.01) in pigs fed the experimental diets supplemented with L-lysine??HCl or $L-lysine{\cdot}SO_4$ produced by A company, irrespective of the two synthetic lysine sources. Although the supplementation of $L-lysine{\cdot}SO_4$ produced by B company tended to improve the ADG and G:F ratio, significant differences were not seen among all treatments and tended to be lower than the L-C (L-lysine HCl) and K-L-S ($L-lysine{\cdot}SO_4$ groups using the product from A company). The digestibility of crude protein (CP) was increased by the supplementation of synthetic lysine (p<0.05), irrespective of the L-lysine source (L-C, K-L-S, C-L-S). The results of this study showed that ADG, G:F ratio, and CP digestibility improved when $L-lysine{\cdot}SO_4$ or L-lysine HCl was supplemented into the weaning pigs' diet. There was a clear difference in efficacy between the two $lysine{\cdot}SO_4$ products based upon the growth performance of weaning pigs. Consequently, the bioavailability of $lysine{\cdot}SO_4$ products should be evaluated before supplementation of synthetic lysine in swine diets.

• 한국식품조리과학회지
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• 제13권2호
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• pp.106-112
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• 1997

향신료인 allspice(Pimenta dioica L.)를 액체배지에 첨가하여 2종류의 식중독세균(Escherichia coli 0157:H7과 Staphylococcus aureus 196E)의 증식과 저온저장중 생존에 미치는 항균효과를 조사하였다 저농도(0~2%, w/v)의 allspice를 함유한 tryptic soy broth(TSB)에 E. coli와 S. aureus를 $10^{5}$~$10^{6}$ cells/$m\ell$가 되게 접종하여 35$^{\circ}C$에서의 증식과 냉장(5$^{\circ}C$)및 냉동(-2$0^{\circ}C$)저장중 생존억제효과를 생균수의 변화로서 조사하였다. 35$^{\circ}C$에서의 E. coli 증식은 1%이내의 향신료 농도에서는 증식이 저해되지 않았으나, 2%의 allspice 존재하에서는 긴 유도기를 거친 후에 증식이 시작되었다. 35$^{\circ}C$에서의 S. aureus의 증식은 0.1%와 0.3%의 allspice 존재하에서는 긴 유도기를 거친 후에 증식이 시작되었으나 0.5~2%에서는 세균의 증식이 억제되어 사멸하였다. 5$^{\circ}C$에서 냉장한 경우에는 E. coli와 S aureus 모두 0.3%의 allspice에 의해 생존이 크게 억제되었으며 0.5%이상의 농도에서는 저장말기에 사멸하였다. -2$0^{\circ}C$에 동결저장하였을 때 E. coli는 저장기간이 길어질수록, 첨가한 향신료의 농도가 높을수록 생존 억제효과가 증대되었다. 동결저장중 S. aureus의 생균수는 저장초기에 급격히 감소한 후 거의 일정수준을 유지하였으며 첨가한 향신료의 농도에 따른 생균수의 차이는 나타나지 않았다. 동결저장에서 0.1%의 향신료를 첨가했을 때 E. coli와 S. aureus는 대조구의 생균수에 비해 1/100이하로 생균수가 감소하여 allspice는 우수한 항균효과를 나타내었다.다.

• 한국수산과학회지
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• 제48권1호
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• pp.76-81
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• 2015

The effects of temperature, photon irradiance, and photoperiod on the growth of Sargassum horneri embryos were examined for female plants collected at Chokpo in Tongyeoung, Gyeongnam Prefecture, Korea on 27 December 2011. Mature plant receptacles were detached, and fertilized eggs were cultured in the laboratory at temperatures of $5-25^{\circ}C$ with photon irradiances of $10-80{\mu}mol\;m^{-2}s^{-1}$ under 14L:10D and 10L:14D photoperiods. Germination and embryo growth were rapid at $20-25^{\circ}C$ and $40{\mu}mol\;m^{-2}s^{-1}$ under 14L:10D. The number of rhizoids in the germinated young thalli was high at high photon irradiances ($40-80{\mu}mol\;m^{-2}s^{-1}$) and $15-20^{\circ}C$. At $20^{\circ}C$ and 14L:10D, vigorous growth of main and lateral branches was observed; however, at $5^{\circ}C$ under both photoperiods, plant growth decreased markedly. In the present study, S. horneri grew well at high temperatures ($20-25^{\circ}C$) and high photon irradiances ($40-80{\mu}mol\;m^{-2}s^{-1}$) with a 14L:10D photoperiod.

• Journal of Power Electronics
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• 제17권4호
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• pp.905-913
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• 2017

To enhance the zero-voltage switching (ZVS) range and power density of the phase-shift full-bridge (PSFB) ZVS converters used in geophysical exploration, an additional resonant inductor is used as a leakage inductance and a blocking capacitor which is equivalent to interlayer capacitance is integrated into a novel integrated inductor-capacitor-transformer (L-C-T). The leakage inductance and equivalent interlayer capacitance of the novel integrated L-C-T are difficult to determine by conventional methods. To address this issue, this paper presents accurate and efficient methods to compute the leakage inductance and equivalent interlayer capacitance. Moreover, the accuracy of this methodology, which is based on electromagnetic energy and Lebedev's method, is verified by an experimental analysis and a finite element analysis (FEA). Taking the problems of the novel integrated L-C-T into consideration, the losses of the integrated L-C-T are analyzed and the temperature rise of the integrated L-C-T is determined by FEA. Finally, a PSFB ZVS converter prototype with the novel integrated L-C-T is designed and tested.