• Asian-Australasian Journal of Animal Sciences
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• 제18권1호
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• pp.42-47
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• 2005

The possibility of using Moringa oleifera as a ruminant protein supplement was investigated by comparison between nutritive and anti-nutritive value of its different morphological parts with that of conventionally used Leucaena leucocephala leaf meal (LL). Parameters determined were chemical composition, rumen degradable protein (RDP), acid detergent insoluble protein (ADIP), pepsin soluble protein (PESP), non-protein nitrogen (NPN) total soluble protein (TSP) and protein potentially digested in the intestine (PDI). Total phenols (TP) and total extractable tannins (TET) were also evaluated as anti-nutritive factors. In vitro gas production characteristics were measured and organic matter digestibility (OMD) was estimated basing on 24 h-gas production. Crude protein content ranged from 265-308 g/kg DM in M. oleifera leaves (MOL) and seed cake (MOC) respectively. Leucaena leucocephala and Moringa oleifera soft twigs and leaves (MOLSTL) had CP content of 236 and 195 g/kg DM while Moringa oleifera soft twigs alone (MOST) and Moringa oleifera bucks (MOB) had 160, 114 and 69.3 g/kg DM respectively. RDP was highest in (MOC) (181 g/kg DM) followed by (MOL) (177 g/kg DM) and was lowest in MOB (40 g/kg DM). The proportion of the protein that was not available to the animal (ADIP) was (p<0.05) higher in MOL and MOC (72 and 73 g/kg DM) respectively and lowest in LL (29 g/kg DM). The PDI was high in LL (74 g/kg DM) followed by MOC (55 g/kg DM) then MOL (16 g/kg DM). PESP was highest (p<0.05) in MOC followed by MOL then LL (273, 200 and 163 g/kg DM respectively). MOC exhibited highest NPN content (116 g/kg DM) and was lowest in MOB (18 g/kg DM) (p<0.05). Highly (p<0.05) TSP was observed in MOC and MOL (308 and 265 g/kg DM respectively) followed by LL (236 g/kg DM). MOL had negligible TET (20 g/kg DM) when compared with about 70 g/kg DM in LL. Highly (p<0.05) b and a+b values were observed for MOLSTL (602 and 691 g/kg DM respectively) followed by MOL (490 and 538 g/kg DM). Highest c value was observed in MOSTL followed by MOC and MOL (0.064, 0.056 and 0.053 rate/hour) respectively. OMD was highest (p<0.05) for MOSTL followed by MOC and then MOL (579, 579 and 562 g/kg DM respectively). LL exhibited lower (p<0.05) OMD (467 g/kg DM). It was concluded from this study that the high crude protein content in MOL and MOLST could be well utilized by ruminant animals and increase animal performance however, high proportion of unavailable protein to the lower gut of animals and high rumen degradable protein due to negligible tannin content render it a relatively poor protein supplement for ruminants. MOC can be a best alternative protein supplement to leaves and leaves and soft twigs for ruminants.

• Clinical and Experimental Reproductive Medicine
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• 제25권3호
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• pp.299-304
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• 1998

Despite the rapid development of assisted reproductive technologies (ART) in recent years, implantation rates after replacement of embryos into the uterine cavity remains low. Several techniques such as culture conditions based on formulations of human tubal fluid and various ART techniques as GIFT, ZIFT, TET have been adopted in recent years to improve embryo viability in vitro and implantation rates. Also, coculture of human IVF-derived embryos have been used in an effort to increase the number of viable embryos following IVF and to improve synchrony between the developing embryo and the uterine environment. The aim of this study was to evaluate whether the use of co culture with autologous cumulus cells has a significant beneficial effect on the development of embryos in vitro and its relation to the pregnancy rates in 120 patients with previous failed IVF-ET from September, 1995 to January 1998. We obtained the results from which significant improvement in the quality of viable embryos were observed using a coculture system with autologous cumulus cells, but pregnancy rates in this group of patients did not differ from the rate in the standard IVF group during the same period. Our study shows that a simplified short-term coculture system with autologous cumulus cells may help rescue moderate quality embryos to cleave regularly.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 1998년도 학술발표회 논문집
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• pp.632-637
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• 1998

The purpose of this study of this study is to find tide and tidal current variation by three dimensional numerical model of tide and tidal current in the bay of Cheonsu in Korea. On the basis of the observed data on water temperature and salinity data and wind data of summer(July) in the bay of Cheonsu in Korea, water circulation in the bay of Cheonsu is investigated with use of a robust diagnostic numerical model, including calculated co-range and co-tidal charts of M2 tide are similar to the observed ones. The residual flow Pattern at the surface layer during summer formed clockwise circulation in the front coastal the dike of the Sosam A zone(Ganwor island) and Taeju island. The residual flow pattern at the 15m layer during formed clockwise circulation in the front Taeju island. The residual flow Pattern at the surface layer formed anti-clockwise circulation in the upper Sangmok and Naepasu island.

• Reproductive and Developmental Biology
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• 제37권3호
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• pp.109-115
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• 2013

Until recently the most popular tetracycline-inducible gene expression system has been the one developed by Gossen and Bujard. In this study, we tested the latest version of same system and the results are summarized as follows: Compared with previous one, the difference of new system are minor changes of nucleotide sequences in transactivator and tetracycline response element (TRE) regions. Sensitivity to the doxycycline (a tetracycline derivative) was improved. Leakiness of GFP marker gene expression in non-inducible condition was significantly decreased. Higher expression of the marker gene was observed when the cells were fed with doxycycline-containing medium. Optimal insertion site of woodchuck posttranscriptional regulatory element (WPRE) sequence which was known to increase gene expression was different depending on the origin of cells. In chicken embryonic fibroblast, location of WPRE sequence at 3' end of TRE resulted in the highest GFP expression. In bovine embryonic fibroblasts, 3' end of transactivator was the best site for the GFP expression.

• Reproductive and Developmental Biology
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• 제34권3호
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• pp.193-199
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• 2010

We report here the production of transgenic chickens that can regulate human erythropoietin (hEPO) gene expression. The glycoprotein hormone hEPO is an essential for viability and growth of the erythrocytic progenitors. Retrovirus vector system used in this study has two features including tetracycline-controllable promoter and woodchuck hepatitis virus posttranscriptional regulator element (WPRE). The former is for to reduce the possibility of physiological disturbance due to constitutional and unregulated expression of hEPO gene in the transgenic chicken. The latter is for maximum expression of the foreign gene when we turn-on the gene expression. A replication-defective Moloney murine leukemia virus (MoMLV)-based vectors packaged with vesicular stomatitis virus G glycoprotein (VSV-G) was injected beneath the blastoderm of non-incubated chicken embryos (stage X). Out of 325 injected eggs, 28 chicks hatched after 21 days of incubation and 16 hatched chicks were found to express the hEPO gene delivered by the vector. The biological activity of the recombinant hEPO in transgenic chicken serum was comparable to its commercially available counterpart. The recombinant hEPO in transgenic chicken serum had N- and O-linked carbohydrate simillar to that produced from in vitro cultured cells transformed with hEPO gene.

• Membrane and Water Treatment
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• 제7권4호
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• pp.355-365
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• 2016

The improvement of fouling resistance of porous polymeric membrane is one of the most important targets in membrane preparation for water purification in many process like wastewater treatment. Membranes can be modified by various techniques, including the treatment of polymer material, blending of hydrophilic polymer into polymer solution, and post treatment of fabricated membrane. This research proposed the modifications of morphology and surface property of hydrophobic membrane by blending polyethersulfone (PES) with three polymeric additives, polyvinylpyrrolidone (PVP), Pluronic F127 (Plu), and Tetronic 1307 (Tet). PES hollow fiber membranes were fabricated via dry-wet spinning process by using a spinneret with inner and outer diameter of 0.7 and 1.0 mm, respectively. The morphology changes of PES blend membrane by those additives, as well as the change of performance in ultrafiltration module were comparatively observed. The surface structure of membranes was characterized by atomic force microscopy and Fourier transform infra red spectroscopy. The cross section morphology of PES blend hollow fiber membranes was investigated by scanning electron microscopy. The results showed that all polymeric additives blended in this system affected to improve the performances of PES membrane. The ultra-filtration experiment confirmed that PES-PVP membrane showed the best performance among the three membranes on the basis of filtration stability.

• 대한전자공학회논문지
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• 제26권5호
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• pp.38-45
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• 1989

보론이 100ppm으로 도우핑된 비정질 실리콘을 이용한 쌍극 박막 트랜지스터를 CVD 방법으로 제작하여 전기적 특성을 조사하였다. 쌍극 박막 트랜지스터에 인가한 트레인 전압이 증가하면 정공채널의 드레인 전류는 전자와 정공의 주입에 의해 크게 증가한다. 또한 게이트 전압의 인가 시간에 따른 드레인 전류는 streched exponential로 감소하는데, 이는 전자축적층에 의해 생기는 댕글린 본드 밀도의 변화가 수소의 확산과 동일한 시간 의존성을 갖는 것을 의미한다. 이러한 실험 결과로 부터 보론이 도우핑된 수소화된 비정질 실리콘에 게이트 전압을 인가하거나, 빛 조사시 도우핑 효율이 변화함을 알 수 있다.

• 생약학회지
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• 제38권1호
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• pp.62-66
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• 2007

Ethanol extract from Salvia miltiorrhiza (SME) was tested for breast cancer chemoprevention and metastasis by measuring the activites of cytochrome P45O 1A1, aromatase, ornithine decarboxylase (ODC), and matrix metalloproteinase (MMP)-9. SME significantly inhibited cytochrome P45O 1A1-mediated ethoxyresorufin O-deethylase (EROD) activity in a dose-dependent manner in a concentration range of 100${\sim}$l,200 ${\mu}g/ml$ (p<0.01). Microsomal aromatase (estrogen synthase) activity was suppressed 54.9%${\sim}$77.5% by the SME at concentration of 600${\sim}$l,200 ${\mu}g/ml$. ODC activity induced by 12-O-tet-radecanoylphorbol-13-acetate (TPA) was significantly reduced by the SME 900 and 1,200 ${\mu}g/ml$ (p<0.05) in MCF-7 breast cancer cells. In addition, SME (900 and 1,200 ${\mu}g/ml$) markedly inhibited MMP-9 activity, a key role in cancer metastasis. Therefore, SME is worth further investigation with respect to breast cancer chemoprevention or therapy.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1992년도 추계학술대회
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• pp.117-122
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• 1992

In systems in which inductive coupling between a pancake-shaped coil on the surface of the body and a similar coil within the body is utilized for the transfort of electromagnetic energy, the minimization of temperature rise in the tissue is intimately related to the achievement of minimum losses in the region of the implanted coil. The new class of amplifiers, named "class E", for inverter is defined and is illustrated by a detailed description and a set of desist equations for one simple member of the class. For TET circuit the authors measured 65 to 76 percent efficiency at 1985kHz at 30 to 50 W output from IRF250 MOSFET transistor.

• 대한기계학회논문집B
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• 제37권11호
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• pp.1015-1022
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• 2013

본 연구에서는 현재 개발중인 200kW 급 마이크로 가스터빈의 운전 특성을 모사하였다. 세부적인 성능 데이터를 이용하여 부분부하 제어방식(터빈 입구온도 제어방식(constant TIT control)과 터빈 출구온도 제어방식(constant TET control))과 외기온도에 따른 성능 및 작동특성을 분석하였다. 넓은 운전 범위에 대하여 압축기 서지마진과 터빈 입출구 온도 같은 작동 파라미터의 민감도를 단위 연료량 변화에 따라 예측하였다. 정상상태 계산으로 부분부하 변동 시 최대서지마진의 감소에 대한 정보를 민감도 분석을 통해 알 수 있다.