• Journal of Crop Science and Biotechnology
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• 제10권2호
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• pp.92-97
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• 2007

Antibiotics used for suppressing Agrobacterium in plant transformation procedure might have negligible effects on plant tissues and regeneration. The effects of antibiotics on growth suppression of Agrobacterium and plant regeneration were investigated for enhancing Agrobacterium-mediated transformation using wheat mature embryos. Antibiotics tested, except carbenicillin, were able to suppress that embryos were coated with a layer of Agrobacterium cells in callus induction medium. Agrobacterium growth was suppressed minimally at 50 mg/l of timentin, while cefotaxime and clavamox were completely suppressed at relative high concentration of 250 mg/l. In the treatment of carbenicillin, initiation of growth suppression of Agrobacterium occurred at 750 mg/l of concentration because Agrobacterium KYRT1 contains the carbenicillin resistant gene. In Agrobacterium inoculation, effects of antibiotics were significantly different on the rate of callus induction and shoot formation. Almost embryos were induced calli at 50 mg/l of timentin whereas callus induction rate was achieved above 90% at 100 mg/l and 250 mg/l of cefotaxime and clavamox, respectively. Shoot formation rate was higher in the treatment of timentin than that of cefotaxime and clavamox at 500 mg/l of concentration, respectively. Timentin can be used as a good antibiotics in Agrobacterium-mediated wheat transformation.

• 대한치과의사협회지
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• 제53권7호
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• pp.485-499
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• 2015

Purpose: Delayed intentional replantation was introduced as a new alternative to treat the teeth with severe periodontal involvement. The purpose of this study was to elucidate the possibility of delayed intentional replantation and establish theoretical backgrounds. Materials and Methods: Studies were performed into the following two subjects; (1)Clinical evaluation of patients who underwent delayed intentional replantation using clinical and radiographic data. Severe periodontitis involved teeth were carefully extracted and proper time for delayed replantation was evaluated by analyzing inflammation markers (IL-6, TNF-${\alpha}$). (2) Theoretical studies for efficacy of delayed intentional replantation using (-)-Epigallocatechin-3-gallate (EGCG) for preservation of periodontal ligament cells on root surface by minimizing inflammation and treatment of inflammatory extraction sockets. Results: Meaningful success ratio and survival rate were found in delayed intentional replantation showing reduced bone loss and maintained bone level. Additionally, viability of EGCG applied periodontal ligament cells was much higher than control group. Also, EGCG promoted healing of inflammatory extraction sockets by inhibiting inflammatory cell proliferation. Conclusion: Within the limitations of this study, 1-2 weeks after extraction is an appropriate time to do delayed intentional replantation. Also, EGCG provides helpful effects on viability of periodontal ligament cells and periodontium.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1990년도 Proceedings of International Symposium on Korean Ginseng, 1990, Seoul, Korea
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• pp.58-64
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• 1990

The effects of ginseng saponins, G-Rbl and G-Rc on the rat liver LDH A-gene transcnptional activity was investigated during pro-replicative phase of rat liver after partial hepatectomy. Changes in LDH A-mRNA levels in regenerating rat liver after intraperitoneal administrations of G-Rbl of G-Rc were tested by slot blot hybridization methods. The results showed that G-Rbl (1 mg/100g B.W) and G-Rc (1 ma/100g B.W) caused marked increases of LDH A-mRNA contents by respectively 1.9- and 1.5-fold in rat liver at 5·hours after partial hepatectomy. Dose dependent effect of G-Rbl and G-Rc (1-25 mg/100g B.W) on the LDH A-mRNA levels on regenerating rat liver were also analyzed. The maximal in- creases of liver LDH A-mRNA levels were observed with the doses of 1 mg for G-Rbl and 5 mg for G-Rc However, when the administration doses of G-Kbl and G-Rc were increased to 20 mg, G-Rbl caused a marked decrease of LDH A-mRNA level to 61% of those in sham-operated rat liver In contrast, G-Rc slightly decreased the liver LDH A-mRNA contents by 30% as compared to those of the maximum value but still maintained 22% higher LDH A-mRNA levels then those of sham-operated rate liver. On the basis of these experimental results, we conclude that ginseng saponin, G-Rb 1 and G·Rc have stimulatory effect at the lower concentration (1 mg/100g B.W) and inhibitory effect at the higher concentration (20 moi loos 5.W) on the LDH A-gene transcription during regeneration of rat liver, Additionally we also investigated the stimulatory effects of ginsenosides on the protein and DNA synthetic activities in hepatocyte primary cell cultures isolated from regenerating rat liver. Both of G·Rc and -Re increased the synthetic rates of hepatocytes proteins and DNA at the administration doses of 50 ug and 100 ug/3 ml/dish respectively representing 1.3-1.6 fold increases. From these results we postulate that G-Rc and -Re may have a mitogen enhancer activity for the hepatocyte proliferation during rat liver regeneration period. Keywords Inductive effects of ginsenosides, G-Rb, -Rc, and -Re, rat LDH A-gene transcription, the sin thetic rate of proteins and DNA in regeneration rat liver.

• 한국환경생태학회지
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• 제29권5호
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• pp.785-790
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• 2015

대면적 개벌의 대안으로서, 대상 개벌은 생산림지의 생태 조건 보전과 임분 재생을 모두 고려하는 작업법이다. 그러나 우리나라에서는 대상 벌채 기법의 적용 및 효율성에 대한 연구를 찾아보기 어렵다. 본 연구는 강원도 삼척에서 2012년부터 2014년까지 소나무림 대상 벌채 (10m, 20m 및 40m) 처리 전 후의 하층식생 반응 및 소나무 재생과 임분 환경 변화와의 상관성을 방형구법을 적용하여 조사 및 분석하였다. 하층식생 피도 및 종다양성은 대상 벌채 넓이에 상관없이 교목 종 및 광선호 종의 확장에 의해 증가하는 경향이었고, 신갈나무, 맑은대쑥 및 산딸기 등의 벌채 후 잔존 교목 및 광선호 종들의 활발한 증가가 관찰되었다. 대상 벌채 구역의 소나무 정착은 수관층 환경 (광량 및 수관열림도) 및 토양나출도와는 정의 상관, 그리고 하층식생 및 임상 목질잔해물의 피도와는 음의 상관을 나타내었다.

• 한국동물학회지
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• 제14권4호
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• pp.199-204
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• 1971

放射線照射에 의해서 尿 및 血液內에 다량의 deoxycytidine (CdR)이 流出하는 것을 볼수가 있는데, 이것이 DNA의 合成이나 分解와 어떤 관련성이 있으며, 아울러 어느 臟器의 DNA가 放射線感受性이 큰지의 여부를 밝히기 위해서 400R의 X 線을 흰쥐에 全身照射시켜, 간, 지라 및 흉선을 切除하여 均質化시킨 후, CdR-2-$^14 C$을 써서 DNA의 合成率 및 分解率을 測定하였다. DNA의 合成率은 흉선의 경우, 照射후 1 $\\sim$ 3日에 가장 심한 抑制現象이 나타났으며 5日후 부터는 점차 回復됨을 볼 수 있었고, 한편 간과 지라의 경우는 抑制의 정도가 흉선에 비해서 적었으며 回復도 훨씬 빨리 이루어졌다. DNA의 分解率은 지라와 흉선의 경우 비슷하여서 照射후 1日에 영향이 極大로 나타냈으며 回復도 아주 늦게 일어남을 볼 수 있었는데 반해서, 간의 경우는 分解도 덜 일어났으며 回復도 아주 빨리 일어남을 알 수 있었다. 이와 같은 결과는 각종 臟器의 放射線感受性의 차와 再生能의 차에 의해서 나타나는 현상임을 알 수 있고 CdR의 流出量의 增加는 放射線에 의한 DNA合成의 抑制와 DNA分解의 促進의 두가지 요인에 기인하는 것으로 추정되었으며, 전자의 경우는 흉선이, 후자의 경우는 지라와 흉선이 같은 정도의 重要性을 지니고 있음을 알 수 있었다.

• Korean Chemical Engineering Research
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• 제61권3호
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• pp.368-377
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• 2023

천연가스복합발전 공정은 일반 석탄 화력발전 공정에 비해 이산화탄소 배출량이 낮아 최근에 발전 플랜트로서 많은 관심을 받고 있다. 그럼에도 불구하고 이산화탄소 배출을 완전히 억제하기는 어려우므로 이산화탄소 포집공정이 필요하며 본 연구에서는 천연가스복합발전 플랜트에서 발생하는 배기가스 내 낮은 이산화탄소 농도를 고려해 포집공정을 구성하고 운전조건을 최적화하는 연구를 수행하였다. 최적화 연구를 위해 상용 시뮬레이션 프로그램으로 천연가스복합발전 공정과 습식 이산화탄소 포집공정이 결합된 전체 공정을 모델링 하였으며, 이를 이용해 다양한 조건에서 이산화탄소 흡수율, 흡수제 재생율, 천연가스복합발전 공정 내 전력 손실율을 종합적으로 고려한 최적 운전조건을 도출하였다. 특히 본 연구에서는 기존에 이산화탄소 포집공정에서 포집된 이산화탄소 톤당 에너지 소모량만을 주요 지표로 검토하던 것과 달리, 천연가스복합발전 공정 내 스팀 사용으로 인한 발전효율 저감, 운전조건 변화에 따른 이산화탄소 흡수율 및 흡수제 재생율 변화의 측면도 함께 고려하여 공정 전반의 성능을 종합적으로 고려할 수 있도록 하였다. 결론적으로 재생탑 재비기 온도가 120 ℃가 되었을 때 가장 좋은 결과를 보이는 것으로 나타났으며, 그 원인을 분석하였다.

• 상하수도학회지
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• 제29권1호
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• pp.65-75
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• 2015

In this study, cation and anion exchange process for performance evaluation was conducted. A pilot plant for the ultrpure water production was installed with the capacity of $25m^3/d$. The various production rate and regeneration of ion exchange rate were tested to investigate the design parameters. The test resulst was applied to calculate the operating costs. Changing the flow rate of the ion exchange capacity of the reproduction reviewed the cation exchange process as opposed to the design value is 120 to 164% efficiency, whereas both anion exchange process is 82 to 124% efficiency, respectively. This results can be applied for more large scale plant if the scale up parameters are consdiered. The ion exchange capacity of the application in accordance with the design value characteristic upon application equipment is expected to be needed. In this study, the performance of cation and anion exchange resin process was evaluated with pilot plant($25m^3/d$). The ion exchange capacity along with space velocity and regeneration volume was evaluated. In results, the operation results was compared with design parameters.

• 한국자동차공학회논문집
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• 제19권3호
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• pp.52-56
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• 2011

Active regeneration in CDPF requires $O_2$ which regenerates soot at high temperature. However, small amount of NO can interrupt $O_2$ regeneration in CDPF. To verify this phenomena, soot oxidation experiments using a flow reactor with a $Pr/CeO_2$ catalyst are carried out to simulate Catalyzed Diesel Particulate Filter (CDPF) phenomena. Catalytic soot oxidation with and without small amount of NO is conducted under tight contact condition. As the heating rate rises, the temperature gap of maximum reaction rate is increased between with and without 50ppm NO. To accelerate the $NO_2$ de-coupling effect, CTO process is performed to eliminate interfacial contact for that time. As CTO process is extended, temperature which indicates peak reaction rate increases. From this result, it is found that small amount of NO can affect tight contact soot oxidation by removal of interfacial contact between soot and catalyst.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.1461-1467
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• 2009

The electric railway is a clean and energy saving system, because it requires relatively less energy than automobiles by transporting the same passengers or goods. Six thousands of vehicles are operated on Korean urban transit system. This system is 95% of regeneration system. Especially, the VVVF-Inverter vehicle has a merit of the highest regeneration rate. Energy consumption is 90% for traction and 10% for auxiliary supply. Braking energy is about 40% of energy consumption. Up to 40% of the tractive power of vehicles capable of returning energy to the power supply can be regenerated during braking and that this energy can be used to feed vehicles which are accelerating at the same time. The energy generated by braking vehicle would simply be converted into waste heat by its braking resistors if no other vehicle is accelerating at exactly the same time. Such synchronized braking and accelerating can not be coordinated, the ESS(energy storage system) stores the energy generated during braking and discharges it again when a vehicle accelerates. This paper presents field tests about the energy saving rate of the developed ESS. when the ESS is on/off, energy saving rate of the ESS is tested. The verification test in the field focused on energy saving.

• Journal of Plant Biotechnology
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• 제4권3호
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• pp.129-134
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• 2002

We report the development of a new selection system for the transformation of pepper plants by mannose. In order to achieve this, we first tested several factors related to regeneration conditions. Among the 30 inbred lines examined, line P9l5 was able to generate shoots at the highest rate from both cotyledons and hyporotyls in MS media. A dosage curve for optimizing the selection conditions was established by mixing mannose (range 0-50 g/L) and sucrose (range 0-30 g/L). The least selection pressure on shoot formation was created by a mixture of sucrose and mannose at 20 g/L and 15 g/L, respectively, and the threshold for ultimate tissue death was 50 g/L of mannose irrespective of the sucrose concentration. However, we found that mannose itself was not the sole inhibitor of pepper shoot development. High concentrations of sucrose (30 g/L) contributed additively to the inhibition of shoot formation at higher mannose concentrations. Genotype preference is a major factor that enhances regeneration ability in mannose media, as was observed in MS media. P9l5 and P410 line had high regeneration rates under mannose selection conditions in the presence of Agrobacterium infection. Different virulence levels of Agrobacterium strains did change the regeneration rates, probably due to interaction with the specificities of the inbred lines. Taken together, P9l5 offers the best pepper inbred line for transformation and we recommend a selection condition of 20 g/L of sucrose and 15 g/L or more of mannose up to 50 g/L in media.