• 한국산림과학회지
• /
• 제68권1호
• /
• pp.11-17
• /
• 1985

지위지수(地位指數)의 사정(査定)의 기초(基礎)가 되는 수고생장곡선(樹高生長曲線)을 작성(作成)하기 위하여 수고(樹高)(H)를 수령(樹令)(A)의 함수(凾數)로 표시(表示)한 10개(個)의 모형(模型)을 수용(授用)한 결과(結果) $H=K-ab^A$식(式)이 가장 적합(適合)한 것으로 나타났다. 이 모형(模型)에 따라 낙엽송림(林)의 수고추정식(樹高推定式) $H=28.364-26.125(0.818)^A$ ($R^2=0.999$)와 잣나무림(林)의 수고추정식(樹高推定式) $H=26.331-25.125(0.886)^A$ ($R^2=0.999$)를 각각 도출(導出)하였다 그 다음, 추정(推定)된 수고생장곡선(樹高生長曲線)에 의하여 Bryant 법(法)의 계산과정(計算過程)을 거쳐 두 수종(樹種)의 지위지수표(地位指數表) 및 지위지수곡선(地位指數曲線)을 작성(作成)하고, 이를 비교(比較)하여 보면 지위지수급(地位指數級) 6-18에서는 낙엽송이 잣나무보다 높게 추정(推定)되고, 지위지수급(地位指數級) 20에서는 잣나무가 낙엽송보다 다소 높게 추정(推定)되었다.

• Journal of the Korean Wood Science and Technology
• /
• 제10권3호
• /
• pp.133-134
• /
• 1982

This experiment has been made to investigate the absorption of watersoluble zinc chloride by Pinus densiflora S. et Z. at different moisture content, under soaking process, to decide the optimum content condition for the maximum absorption of zinc chloride by the wood tested and to investigate the concentration of zinc chloride affecting each moisture content of wood. Material was cut in the Dept. of Forest, College of Agr. S.N.U. Suwon, Korea. Sample was divided into sap and heartwood group and cut $2{\times}2{\times}2\;cm$ in size, having exact three dimensions, using the part of D.B.H. The numbers of sample were 20 pieces for each moisture content condition for both sap and heartwood. Especially, the samples were protected from exposure to keep moisture content in green condition. The ranges of moisture content tested were as the table 3 and 4. The conclusions were as follows: 1. With 3% zinc chloride solution, the rate of absorption decreased with the time increased, if the air seasoned Korean red pine (Pinus densiflora S. et Z.) was treated in steeping process. Initial absorption for 30 minutes was more than 50% of total absorpon for 24 hours. 2. Rate of absorption was same under the green condition, while rate of absorption under the moisture content 7 to 30% varied. 3. Although it was not quite proportional change in the absorption with the difference of moisture content, the great change in the absorption occured by seasoning. With exception sap green condition, sapwood twice more permeable than the heartwood in the oven dried condition and it has been observed the nearly same amount of absorption at the moisture content of 7%, 10% and 15% respectively in heartwood. 4. It was better from water in wood from view-point of absorption of zinc chloride solution, but it was difficult practically to obtain the smallest moisture content, and then it was decided that values of allowable moisture content, on the basis of mean absorption, were 15% to 20% in the sapwood, and in the heartwood, 10% to 15%. The mean absorption for each moisture content in the sap and the heartwood were as following. 5. In general, the concentration of zinc chloride after steeping was nearly same between moisture content and sap and heartwood respectively.

• Journal of Microbiology and Biotechnology
• /
• 제22권8호
• /
• pp.1170-1176
• /
• 2012

In this study, we aimed to evaluate the effect of ${\alpha}$-cyperone on S. aureus. We used a hemolysin test to examine the hemolytic activity in supernatants of S. aureus cultured with increasing concentrations of ${\alpha}$-cyperone. In addition, we evaluated the production of ${\alpha}$-hemolysin (Hla) by Western blotting. Real-time RT-PCR was performed to test the expression of hla (the gene encoding Hla) and agr (accessory gene regulator). Furthermore, we investigated the protective effect of ${\alpha}$-cyperone on Hla-induced injury of A549 lung cells by live/dead and cytotoxicity assays. We showed that in the presence of subinhibitory concentrations of ${\alpha}$-cyperone, Hla production was markedly inhibited. Moreover, ${\alpha}$-cyperone protected lung cells from Hla-induced injury. These findings indicate that ${\alpha}$-cyperone is a promising inhibitor of Hla production by S. aureus and protects lung cells from this bacterium. Thus, ${\alpha}$-cyperone may provide the basis for a new strategy to combat S. aureus pneumonia.

• 한국수정란이식학회지
• /
• 제15권3호
• /
• pp.247-253
• /
• 2000

This study was undertaken to optimize enucleation and reconstitution methods for the production of cloned mice by somatic cell nuclear transfer Outbred ICR mouse oocytes at the metapahse- II stage were retrieved from female mice superovulated by PMSG and hCG. In Experiment 1, oocytes were enucleated in medium supplemented with cytochalasin B (CCB) of 3 levels (0, 7.5 or 15 $\mu\textrm{g}$/mL), and higher rate of encleation was obtained at 7.5 and 15 $\mu\textrm{g}$/mL than at $\mu\textrm{g}$/mL. In Experiment 2, oocytes enucleated in 7.5 $\mu\textrm{g}$/mL CCB-containing medium were reconstituted with different types of somatic cell by following methods; 1) cumulus cells by direct cell injection, 2) cumulus cells by electric fusion (1.25 kV/cm, 2 pulses for each 70 $mutextrm{s}$) or 3) STO cells by the electrofusion. Electrofusion of STO cells with enucleated oocytes yielded the greatest (P<0.05) rate of reconstitution without lysis (76%) than any other combinations. Although significant decrease in the rate of somatic cell introduction was found, the electrofusion of cumulus cells yielded better rate of reconstitution than direct injection (0 vs. 18%). In Experiment 3, the duration of electric stimulation for the fusion was changed to either 50 $mutextrm{s}$ or 90 $mutextrm{s}$, but no significant improvement of reconstitution efficacy was obtained. In conclusion, this study showed that ICR mouse oocytes could be used for the production of reconstituted oocytes and a fusion method of 1.25 KV/cm with 2 pulses using 570 cell was the optimal.

• Applied Biological Chemistry
• /
• 제15권3호
• /
• pp.229-240
• /
• 1972

토성에 따라 합리적인 PCP시용량을 결정하고 아울러 어독해의 추정으로 무어독 처리방법을 강구하기위한 기초자료를 얻고자 물리 화학적 성질을 달리하는 수종의 충북지방 답토양을 시료로 하여 PCP의 흡착관계를 살펴본바 그 결과는 다음과 같다 1. 토양의 점토함량, 전질소, 유기물, CEC, 치환성염기, 인산흡수계수등과 PCP 흡착과의 사이에는 正의 상관이, pH와는 부(負)의 상관을 보여 주었으나 모두 유의성은 인정되지 않았다. 그러나 점토함량, $H^+$, Mg 및 CEC와 PCP흡착과는 비교적 큰값을 보여주어 주목할만한 일이었다. 2. 토성별로 PCP흡착은 식토>양로>사질양토의 순이었다. 3. $H_2O_2$처리 토양에서의 PCP흡착은 현저하게 저하하지만 그 줄어든 비율은 부식의 함량에 비례하지는 않았다. 4. 치환성 염기처리토양에서의 PCP흡착은 $H^+$-토양>$K^+$-토양>$Na^+$-토양> $Ca^{++}$-토양>$Mg^{++}$-토양의 순이었다. 5. PCP의 흡착관계를 Langmuir's adsorption isotherm과 Freundlicr's adsorption isotherm으로 표현가능하며 이로서 PCP의 최대 흡착량과 결합 energy 및 흡착층(吸着層)의 길이를 산출할수 있었다. 6. 토성별로 PCP 최대흡착량을 보면 식양토는 213.13mg/100gr, 양토는 $97.28{\sim}121.59mg/100gr$, 사양토는 $32.93{\sim}91.74mg/100gr$ 이 었다. 7. 무어독처리를 위한 한계시용량의 혼합토층의 깊이는 진천토양이 0.88cm로 가장 얕은 그리고 내산리 사질양토는 4.29cm로 가장 깊은 혼합시용을 요한다.

• 한국가축번식학회지
• /
• 제17권2호
• /
• pp.141-148
• /
• 1993

This studies were carried out to investigate the effects of co-culture with cumulus cells, oviduct epithelial cells and uterine endometrium cells on the in-vitro fertilization and cleavage rate of bovine follicular oocytes. The ovaries were obtained from slaughtered Korean native cows. The follicular oocytes surrounded with cumulus cells were recovered by aspirating follicular fluids from the visible follicles of diameter 3~5 mm. The follicular oocytes were cultured in TCM-199 medium containing hormones and 10% FCS for 24~48 hrs in a incubator with 5% CO2 in air at 38.5$^{\circ}C$ and then matured oocytes were again cultured for 12~18 hrs with motile capacitated sperm by preincubation. The results obtained in these experiments were summarized as follows: 1. The in vitro maturatin and fertilization rate of bovine oocytes co-cultured with cumulus cells in TCM-199 medium were 64.0~74.1% and 40.0~58.6% respectively. And in-vitro fertilization rate of cumulus-enclosed oocytes(55.4%) were significantly(p<0.05) higher than cumulus-denuded oocytes(23.1%). 2. The in-vitro maturatin and fertilization rate of bovine oocytes co-cultured with 1$\times$104 cells/ml, 1$\times$106 cells/ml, 1$\times$108 cells/ml and 1$\times$1015 cells/ml oviduct epithelial cells in TCM-199 medium were 59.3% and 40.7%, 64.0% and 48.0%, 58.3% and 37.5%, 52.0% and 32.0%, respectively. 3. The in-vitro maturation and fertilization rate of bovine oocytes co-cultured with 1$\times$104 cells/ml, 1$\times$106 cells/ml, 1$\times$108 cells/ml and 1$\times$1015 cells/ml uterine endometrium cells in TCM-199 medium were 56.0% and 36.0%, 60.7% and 42.9%, 59.3% and 37.0%, 52.0% and 36.0%, respectively. 4. When the in-vitro fertilized oocytes were co-cultured with cumulus cells, oviduct epithelial cells and uterine endometrium cells, the development rate to be blastocyst was 12.2%, 15.6% and 11.7%, respectively and rates were higher than that of control, 2.1%(P<0.05).

• Applied Biological Chemistry
• /
• 제23권3호
• /
• pp.184-188
• /
• 1980

감귤원토양중 잔류하는 농약성분과 구리함량을 알아보기 위해 1979년 10월말부터 1980년 6월초까지 남제주군 서귀읍 일원에서 실험을 실시하였다. 토양시료는 감귤원의 개원년수에 따라 각각 5년, 10년, 15년, 20년 및 30년된 과원을 임의로 선정하여 각 10점씩 채취하였으며, 각 시료는 다시 토심에 따라 $0{\sim}10cm,\;10{\sim}20cm$, 그리고 $20{\sim}40cm$로 나누어 조사하였다. 실험결과를 요약하면 아래와 같다. 1. 모든 시료에서 유기염소제 살비제인 Kelthane과 Akar 및 구리를 검출할 수 있었으며, Kelthane의 잔류량이 Akar에 비해 높은 수준을 나타냈다. 2. Kelthane, Akar 및 구리의 잔류량은 감귤원의 재배년한에 비례하여 증가하였으며, 토심이 깊어짐에 따라 낮아지는 경향을 보여주었다. 3. Kelthane의 잔류수준은 $trace\;{\sim}l.359ppm$이었으며 조사된 토양전충에 대한 총 잔류량을 5년차 감률원은 0.274ppm, 10년차는 0.441ppm, 15년차는 0.758ppm, 20년차는 0.975ppm, 그리고 30년 이상은 1.310ppm이었으며, 토심별 평균 잔류량은 표층토가 0.327ppm, 중층토가 0.236ppm 그리고, 심층토가 0.189ppm이었고, 총 평균잔류량은 0.25ppm이었다. 4. Akar의 잔류수준은 $trace\;{\sim}0.925ppm$이 었고, 전충토양에 대한 총 잔류량은 5년차가 0.082ppm, 10년차가 0.135ppm, 15년차는 0.178ppm 20년차는 0.591ppm, 그리고 30년 이상은 0.818ppm이었으며, 토심별 평균 잔류량은 표층토가 0.163ppm, 중층토가 0.113ppm 그리고 심층토가 0.085ppm을 나타냈으며 총 평균잔류량은 0.120ppm이었다. 5. 토양중 구리함량은 $trace\;{\sim}40.734ppm$ 범위이었으며 전충토양중의 총 잔류량은 5년차는 2.980ppm, 10년차는 3.300ppm, 15년차는 4.808ppm, 20년차는 8.434ppm, 그리고 30년 이상은 13.001ppm의 수준이었고 토심별로는 표층토 3.187ppm, 중층토 1.732ppm, 그리고 심층토는 1.585ppm을 나타냈으며 총 평균 잔류량은 2.168ppm이었다.

• Journal of Microbiology and Biotechnology
• /
• 제27권6호
• /
• pp.1078-1089
• /
• 2017

Biofilm formation of Staphylococcus aureus is one of its mechanisms of drug resistance. Anti-biofilm screening of 106 compounds from marine-derived fungi displayed that 12 compounds inhibited S. aureus biofilm formation by >50% at the concentration of $100{\mu}g/ml$, and only secalonic acid D (SAD) and B inhibited by >90% at $6.25{\mu}g/ml$ without inhibiting cell growth after 24-h incubation. Meanwhile, it was found that the double bond between C-1 and C-10 of citrinin derivatives and the C-C connection position of two chromone monomers may be important for their anti-biofilm activities. Moreover, SAD slightly facilitated biofilm eradication and influenced its architecture. Furthermore, SAD slowed the cell growth rate in the preceding 18-h incubation and differentially regulated transcriptional expression of several genes, such as agr, isaA, icaA, and icaD, associated with biofilm formation in planktonic and biofilm cells, which may be the reason for the anti-biofilm activity of SAD. Finally, SAD acted synergistically against S. aureus growth and biofilm formation with other antibiotics. These findings indicated that various natural products from marine-derived fungi, such as SAD, could be used as a potential biofilm inhibitor against S. aureus.

• 농업과학연구
• /
• 제3권2호
• /
• pp.184-191
• /
• 1976

북방형(北方型) 목초(牧草)의 하고성(夏枯性) 방제(防除)하기 위하여 1976년(年) 7월(月)1일(日)부터 8(월)月14일(日)까지 Orchard grass, Tall fescue, Red clover, Alfalfa, Crabgrass의 5초종(草種)에 보리짚을 $100g/m^2$, $200g/m^2$, $300g/m^2$ 피복(被覆)하고 목초(牧草)의 성장(成長), 수량(收量) 및 영양성분(營養成分)에 미치는 영향(影響)을 검토(檢討)한 결과(結果) 다음과 같은 결론(結論)을 얻었다. 보리짚 피복(被覆)에 의하여 피복구(被覆區) 지온(地溫)은 무처리구(無處理區)에 비(比)하여 $1.0{\sim}3.04^{\circ}C$의 강하현상(降下現象)을 나타내었다. 피복처리구(被覆處理區)는 무처리구(無處理區)에 비(比)하여 6.0~45%의 성장효과(成長效果)를 나타내었다. $100g/m^2$ 피복구(被覆區)는 무처리구(無處理區)에 비하여 32.77%의 증수효과(增收效果)를 나타내었고 $300g/m^2$구(區) 이상은 부식(腐蝕)에 의하여 7.75%의 감수현상(減收現象)을 표현(表現)하였다. 피복처리구(被覆處理區)에서 생산된 목초(牧草)는 무처리구(無處理區)에 비하여 조단백질(粗蛋白質) 및 가용무질소물(可溶無窒素物)의 증가(增加)를 가져왔고 조지방(粗脂肪), 조섬유(粗纖維) 및 조회분(粗灰分)은 감소현상(減少現象)을 나타내었다.

• 농업과학연구
• /
• 제3권2호
• /
• pp.160-169
• /
• 1976

한국산(韓國産) Pinus속(屬)의 Diploxylon아속(亞屬)의 소나무, 중곰솔, 곰솔, 금강소나무에 대(對)한 류별(類別)을 알아보기 위(爲)하여 GLC에 의(依)한 monoterpene 조성(組成)을 분석(分析) 연구(硏究)하여 다음과 같은 결과(結果)를 얻었다. 소나무, 중곰솔, 곰솔, 금강소나무의 monoterpene은 ${\alpha}$-pinene, camphene, ${\beta}$-pinene, myrcene, limonene, ${\beta}$-phellandrene, terpinolene 외(外)에 2개의 미지(未知)의 조성분(組成分)으로 구성(構成)되어 있다. 소나무와 금강소나무의 주요(主要) monoterpene조성(組成)은 ${\alpha}$-pinene, ${\beta}$-phellandrene, myrcene, terpinolene 이다. 중곰솔의 주요(主要) monoterpene 조성(組成)은 ${\beta}$-pinene, ${\beta}$-phellandrene, ${\alpha}$-plnene, terpinolene 이다. 곰솔의 주요(主要) monoterpene 조성(組成)은 ${\beta}$-pinene, ${\alpha}$-pinene, ${\beta}$-phellandrene, limonene 이다. 소나무, 중곰솔, 곰솔, 금강소나무에서 모두 monoterpene 조성분(組成分)은 개체간에 큰 차이(差異)가 있었다. 중곰솔은 monoterpene 조성(組成)에 있어서 소나무와 곰솔의 중간에 해당되었다. 소나무와 곰솔을 구별(區別)하는 가장 좋은 분류적기준(分類的基準)이 되는 monoterpene의 주성분(組成分)은 ${\alpha}$-pinene, ${\beta}$-pinene, myrcene이었고 소나무는 ${\alpha}$-pinene이 ${\beta}$-pinene보다 항상 많았고 중곰솔을 그 반대(反對)였다. 안면도와 치악산(産) 소나무의 산지별(産地別) 차이(差異)에서는 ${\alpha}$-pinene에서 유이성(有異性)이 보였으나 이는 개체 사이의 변이(變異)가 큰 것에 기인(起因)하는 것으로 추측(推測)된다.