• Title/Summary/Keyword: 응집 현상

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Optimization of Human Thrombopoietin Production in Insert Cells Using Baculovirus Expression System (베큘로 바이러스 발현 시스템에 의한 곤충세포에서의 인간 트롬보포이에틴 생산 최적화)

  • 고여욱;손미영;박상규;안혜경;박승국;박명환;양재명
    • KSBB Journal
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    • v.13 no.2
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    • pp.181-186
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    • 1998
  • In order to obtain high-level production of recombinant human thrombopoietin (rhTPO) in insect cell line, HTI-TN-5B1-4 (TN5), conditions for optimal rhTPO expression such as multiplicity of infection (MOI), the cell density at infection, harvesting time and type of culture method as well as growth media were determined. When TN5 cells were cultured as anchorage-dependent state in 60-mm dish, cell density $2\times^6$ cells,MOI of 10 and Garvesting the culture media at 72 hr post-infection wrere the cinditions for highest rh TPO production. High production of rhTPO was also achieved by using EXPRESS FIVE serum free media rather than SF900II serum free media-1. Anchorage-dependent TN5 cells were adapted as a suspension culture when they were grown in the presence of heparin. TN5 cells were successfully cultured at 0.2 L scale in suspension culture without having aggregation. When TN5 cells were cultured as suspension state, cell density of $0.6\times10^6$ cells/mL, MOI of 1 and harvesting the culture media at 72 hr post-infection, gave the highest yield of rhTPO.

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Synthesis of ceramic particles by hydrothermal method (수열법에 의한 세라믹분말 합성)

  • 김판채;최종건
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06b
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    • pp.219-222
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    • 1996
  • 수열법은 밀폐용기중에서 10$0^{\circ}C$이상의 가열, 가압된 수용액이 반응에 관여하는 것으로써, 수정, CaCO3, AlPO4, GaPO4 등과 같은 단결정의 육성 뿐만 아니라 균일분산계로부터 균일한 결정성의 미립자 합성에도 폭넓게 이용되고 있다. 세라믹분말의 합성에 있어서, 이 방법은 특히 형상, 입자크기의 제어가 용이할 뿐만 아니라 고상법, 졸-겔법, 공침법에서와 같은 열처리, 분쇄과정이 필요없기 때문에 고순도의 초미립자를 얻을 수 있는 장점이 있다. 근년 미국, 일본에서는 수열법을 이용한 유전, 압전체 등 세라믹분말의 일부가 공업적인 규모로 대량 생산되고 있다. 그러나 이에 대한 국내 기술은 아직 초기단계에 이르고 있는 실정이다. 따라서 본 연구실에서는 수열법에 의한 단결정 육성 (예; 자수정, CaCO3, AlPO4, GaPO4, KTP, Emerald 등), 박막제조 (예; GaP, PbTiO3, BaTiO3 등), 정제 (고령토, 장석, 도석 등), 원석처리 (진주, 인공 emerald, 비취 등) 그리고 각종 세라믹분말의 합성 등과 같은 다양한 기반기술의 축적과 동시에 공업화에 대응한 수열장치를 위하여 반응용기의 대형화, 엄밀한 밀폐방식, 실용적인 수열조건 등을 개발해 오고 있다. 본 발표에서는 현재까지의 연구개발 내용 중에서 결정성 미립자에 관련한 세라믹분말의 합성에 대한 일부의 결과들을 보고한다. 일반적으로 수열장치는 전기로, 반응용기, 온도 및 압력제어계 등을 기본으로 하고 있으며 시판용의 대부분이 교반기가 부착된 수직형 (vertical type)이다. 이와 같은 방식에 있어서는 엄밀한 밀폐가 곤란, 반응온도의 한계성 (25$0^{\circ}C$ 이하), 증진율의 한계성 (소량생산) 등과 같은 점이 있기 때문에 본 연구실에서는 개폐식 전기로내에 엄밀한 밀폐가 가능한 수평식(horizontal type)의 반응용기를 채택한 뒤 이를 회전 또는 시이소(seesaw)식으로 움직일 수 있도록 하여 연속공정화, 온도구배의 자율조절 그리고 보다 저온에서도 인위적인 이온의 확산을 효율적으로 유도할 수 있도록 하였다. 이와 같은 방식은 기존의 방식과 비교하여 반응용기 내에 응집현상과 미반응물이 존재하지 않으며 또한 단분산으로 결정성 미립자를 대량적으로 얻을 수 있는 장점이 있었다. 다음은 이상과 같이 본 연구실에서 자체 개발한 수열장치를 이용하여 PbTiO3, (Pb,La)TiO3Mn, BaTiO3, ZnSiO4:Mn, CaWO4 등과 같은 세라믹분말에 대한 합성 실험의 결과이다. 압전성, 초전성이 우수한 PbTiO3 및 (Pb,La)TiO3:Mn 분말의 수열합성은 PbO, TiO2, La2O3 등의 분말을 출발원료로 하여 합성도도 25$0^{\circ}C$부근의 알카리성 용액중에서 결정성 PbTiO3 및 (Pb,La)TiO3:Mn 미립자를 단상으로 얻었으며 입자의 형상 및 크기는 합성온도와 수열용매의 종류에 의존하였다. 유전체로서 폭넓게 응용되고 있는 BaTiO3 분말은 Ba(OH)2.8H2O, TiO2와 같은 최적의 출발원료를 선택함으로써 15$0^{\circ}C$ 부근의 저온영역에서도 용이하게 합성할 수 있었다. 특히 본 연구에서는 수용성인 Ba(OH)2.8H2O를 사용함으로써 host-guest적인 반응을 유도시키는데 있어 물의 가장 실용적이고 효과적인 수열용매임도 알았다. ZnSiO4:Mn, CaWO4, MgWO4와 같은 형광체 분말은 공업적으로 고상반응 또는 습식법에 의해 얻어지고 있으나 이들 방법에 있어서는 분쇄공정으로 인한 형광특성의 저하와 같은 문제점이 있다. 따라서 본 연구에서는 수열법을 이용하여 이들 화합물의 합성을 시도하였으며 그 결과 합성온도 30$0^{\circ}C$ 부근의 알칼리성 용액중에서 수열적으로 얻어짐을 알았다. 여기서의 합성분말을 이용하여 실제 조명램프로 제조한 결과 녹색, 청색 발광용 형광체로서 우수한 형광특성을 나타내었다. 천연에서 소량 산출되고 있는 고가의 (Li,Al)MnO2(OH)2:Co 분말은 도자기의 전사지용 청색안료로써 이용되고 있다. 본 연구실에서는 LiOH.H2O, Al(OH)3, MnO2 등의 분말을 출발원료로 하고 24$0^{\circ}C$ 온도 부근 그리고 물을 수열용매로 하여 천연산에 필적하는 (Li,Al)MnO2(OH)2:Co 분말을 인공적으로 합성하였다.

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Longest First Binary Search on Prefix Length for IP Address Lookup (최장 길이 우선 검색에 기초한 프리픽스 길이에 따른 이진 IP 검색 구조)

  • Chu Ha-Neul;Lim Hye-Sook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.8B
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    • pp.691-700
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    • 2006
  • Based on the destination IP address of incoming packets, the Internet routers determine next hops and forward packets toward final destinations through If address lookup. The bandwidth of communication links increases exponentially fast as well as the routing table size grows significant as the number of single host networks attached to the Internet increases. Since packets should be processed at wire-speed, the increased link speed reduces the processing time of a packet in routers, and hence more efficient and fast IP address lookup algorithms and architectures are required in the next generation routers. Most of the previous IP lookup schemes compare routing prefixes of shorter length first with a given input IP address. Since IP address lookup needs to find the most specific route of the given input, search continues until the longest matched prefix is found while it keeps remembering the current test matching prefix. In this paper, based on binary search on prefix length, we proposed a new IP address lookup algorithm which compares longer prefixes first. The proposed scheme is consisted of multiple tries with prefixes on leaves only. The trie composed of the longest prefixes is primarily searched whether there is a match with the given input. This processing is repeated for the trio of the next longer prefixes until there finds a match. Hence the proposed algorithm provides the fast search speed. The proposed algorithm also provides the incremental update of prefixes while the previous binary search on length scheme does not provide the incremental update because of pre-processing requirement. In this paper, we performed extensive simulations and showed the performance comparisons with related works.

Immune Activity of Mosidae and Quality Characteristics of Brown Rice Dasik Using Mosidae Powder (모시대의 면역 활성 탐색 및 모시대 분말 첨가 현미다식의 품질 특성)

  • Kim, Ae-Jung;Han, Myung-Ryun;Kim, Myung-Hwan;Tae, Ki-Hwan;Lee, Soo-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.5
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    • pp.548-554
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    • 2009
  • The principal objective of this study was to evaluate the immune activity of Mosidae and the physiochemical characteristics of brown rice Dasik prepared with Mosidae (Adenophora remotiflora) powder. We assessed the effects of Mosidae ethanol extract (MEE) on the production of IL-6T, IL-12 and TNF-$\alpha$ by peritoneal exudate macrophages (PEMs) using ELISA. We also determined general compositions, and conducted Hunter's color values, sensory evaluation, and the mechanical characteristics of Mosidae Dasik stored at room temperature ($20^{\circ}C$). With MEE treatment, ILI-6 (75% of LPS: positive control), IL-12 (35.7% of LPS) and TNF-$\alpha$ (27.32% of LPS) were proliferated at a dose of $1000{\mu}g/mL$. In the general compositions of the samples, fat contents of Mosidae Dasik significantly decreased (p<0.05). The more Mosidae powder was added to the samples, the more was the luminance, and Hunter's a and b were significantly decreased (p<0.05). As more Mosidae powder was added to the samples, springiness score was significantly decreased, but the score of hardness, gumminess and chewiness were increased (p<0.05). The results of sensory evaluation showed that there were significant differences in the color, taste and overall quality of the samples (p<0.05), but there was no significant difference in texture. We note that, among the samples evaluated herein, Mosidae stimulates some kinds of cytokines from machrophage and 1% Mosidae Dasik (MPD1) for the best commercial value.

Antibacterial Activity of Hippophae rhamnoides Leaf Extract and the Stability of a Cream with the Extract (비타민나무 잎 추출물의 항균 활성 및 크림의 안정성)

  • Chae, Kyo-Young;Kim, Jung-Eun;Park, Soo-Nam
    • Microbiology and Biotechnology Letters
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    • v.40 no.1
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    • pp.43-49
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    • 2012
  • In this study, we investigated the antibacterial activity and stability of a cream containing Hippophae rhamnoides leaf extract. The MIC values of ethyl acetate fraction from an H. rhamnoides leaf on Escherichia coli, Pityrosporum ovale, Propionibacterium acnes and Staphylococcus aureus were 0.5%, 0.25%, 0.25% and 0.06%, respectively. Stability evaluations, pH, viscosity and absorbance of the cream containing 0.25% ethyl acetate fraction of H. rhamnoides, were performed. The cream was measured under 4 different temperature conditions under sunlight at 2-week intervals for 12 weeks. The viscosity and pH were measured by a comparison of the experimental cream with a similar control cream. The H. rhamnoides extract was found to have contributed to the stability of the emulsion product via a protective effect in maintaining the viscosity of the cream against sunlight. The absorbance variations of the experimental cream at 270 nm were, under sunlight; $45^{\circ}C$, $37^{\circ}C$, $25^{\circ}C$, and $4^{\circ}C$. In addition, any change in color or smell was not observed through the 12 weeks of the experimental period. These results indicated that the cream containing 0.25% ethyl acetate fraction of H. rhamnoides leaf extract was stable. Accordingly, this suggests that further study is needed to provide additional information for manufacturers, who are seeking the application of the extract to improve anti-oxidant and antibacterial activities and the stability of cosmetic products.

Preparation of Halloysite-Based Tubular Media for Enhanced Methylene Blue Adsorption (메틸렌 블루 흡착능 향상을 위한 할로이사이트 기반 튜브형 담체 연구)

  • Jeon, Junyeong;Cho, Yebin;Kim, Jongwook;Shin, Seung Gu;Jeon, Jong-Rok;Lee, Younki
    • Clean Technology
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    • v.27 no.4
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    • pp.359-366
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    • 2021
  • Halloysite nanotubes (HNTs), the multiwalled clay mineral with the composition of Al2Si2O5(OH)4·nH2O, have been highlighted as a low-cost adsorbent for the removal of dyes from wastewater. Although a powder of halloysite presents a high specific surface area, forming media are significantly considered due to sludge-clogging induced by the water-bound agglomeration. However, higher firing temperature to achieve the structural durability of the media and lower utilization rate due to longer penetration depth into the media act as hurdles to increase the dye-adsorption capacity. In this work, the retention of the adsorption capacity of halloysite was evaluated with methylene blue solution after the heat treatment at 750 ℃. In order to improve the utilization rate, tubular media were fabricated by extrusion. The images taken by transmission electron microscopy show that HNTs present excellent structural stability under heat treatment. The HNTs also provide superb capacity retention for MB adsorption (93%, 18.5 mg g-1), while the diatomite and Magnesol® XL show 22% (7.65 mg g-1) and 6% (11.7 mg g-1), respectively. Additionally, compositing with lignin enhances adsorption capacity, and the heat treatment under the hydrogen atmosphere accelerates the adsorption in the early stage. Compared to the rod-type, the tubular halloysite media rapidly increases methylene blue adsorption capacity.

The Process of Overcoming Prejudice and Discrimination Experiences of Mothers with Disabilities (장애아동 어머니가 겪는 편견 및 차별경험 극복과정)

  • Oh, Yeon Soo
    • The Journal of the Korea Contents Association
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    • v.19 no.2
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    • pp.477-490
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    • 2019
  • This study analyzes the process of overcoming prejudice and discrimination experiences of mothers with disabilities and looks for improvement points. It is interviewed 9 mothers of children with disabilities who were experiencing prejudice and discrimination while raising children with disabilities. The data collection was conducted from October to November, 2018 and one by on one in depth interview by using semi - structured questionnaires. Data analysis was done through consensual qualitative research (CQR). The result of CQR while it is a experiencing the process of prejudice and discrimination as well as coping the raising disabled children. 'Prejudice and discrimination experience of mothers with disabilities' and 'overcoming of discrimination experiences of mothers with disabilities' were derived. And the seven sub-regions, 28 categories, were finally constructed. The results of the study are as follows. Firstly, Prejudice and discrimination experiences of mothers with disabilities in raising children with disabilities are view of looking at children with disabilities comparing to those of normal children and children with disabilities. It seems that they want to treat the disabled child as the general child with an attitude of understanding and accepting the disabled child rather than looking at the disabled child with wrong perception, prejudice, stereotypes and rejection. Secondly, The process of overcoming the discrimination experiences of the mother of the disabled child is strengthening the cohesion and cohesion within the family in the process of accepting and coping with the disability family of the child with disabilities even if they raise the child with disability and have difficulties such as recognition bias and discrimination of the general public. Based on the results of this study, we suggested practical and policy implications for the mother's psychological stability of the child with disability and the disabled child's healthy life.

Preparation and Characterization of Physicochemical and Sensory Properties of Bread Enriched with Two Types of Wild Grape Extract (제조방법이 다른 두 종류의 머루즙 첨가가 빵의 이화학적 및 관능적 특성에 미치는 영향)

  • Lee, Byung-Yong;Lee, Malp-Eum;O, Jin-Hwan;Kim, Eun-Cho;Surh, Jeong-Hee
    • Korean journal of food and cookery science
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    • v.26 no.5
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    • pp.636-648
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    • 2010
  • Two types of wild grape extracts(WGE) prepared by different methods were added into butter-top bread at different concentrations(0, 5, 10, 15, 20% of water). Then, the resulting breads were analyzed for their physicochemical and sensory properties in order to identify whether or not the WGE-enriched breads were comparable to control bread in terms of qualities and preferences. Wild grape sugar mixture(WGS), which was prepared by osmotic dehydration of wild grape fruits with the same amounts of sugar, presented significantly lower moisture content and titratable acidity as well as higher pH and sugar content compared to wild grape juice(WGJ), which was produced by boiling the fruits in a vacuum jar and squeezing. The pH of the doughs and breads containing WGE tended to decrease with increasing amounts of WGE, and this phenomenon was more appreciable in those containing WGJ than WGS. This was presumably due to the higher contents of tartaric acid in WGJ. For both types of extracts, hardness, gumminess, and chewiness of the doughs decreased with the addition of WGE, nevertheless, which properties were not remained in the resulting breads. This could be partially attributed to the relatively high degree of baking loss and lower pH of the WGE-enriched breads than those of control bread. Contrary to the mechanical analyses, the sensory properties of the breads were dependent on the WGE type. That is, WGJ-enriched bread showed lower consistency and moistness than control bread, which consequently led to relatively lower overall acceptability. However, WGS addition did not adversely affect the sensory properties of the bread. In particular, addition of 5% WGS somewhat improved the physical and sensory qualities of the bread. Thus, WGE-enriched bread could be produced without loss of bread quality when prepared with 5% WGS.