• Title/Summary/Keyword: Cell retention

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Analysis of the Interface Trap Effect on Electrical Characteristic and Reliability of SANOS Memory Cell Transistor (SANOS 메모리 셀 트랜지스터에서 Tunnel Oxide-Si Substrate 계면 트랩에 따른 소자의 전기적 특성 및 신뢰성 분석)

  • Park, Sung-Soo;Choi, Won-Ho;Han, In-Shik;Na, Min-Ki;Om, Jae-Chul;Lee, Seaung-Suk;Bae, Gi-Hyun;Lee, Hi-Deok;Lee, Ga-Won
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.94-95
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    • 2007
  • In this paper, the dependence of electrical characteristics of Silicon-$Al_2O_3$-Nitride-Oxide-Silicon (SANOS) memory cell transistors and program speed, reliability of memory device on interface trap between Si substrate and tunneling oxide was investigated. The devices were fabricated by the identical processing in a single lot except the deposition method of the charge trapping layer, nitride. In the case of P/E speed, it was shown that P/E speed is slower in the SONOS cell transistors with larger interface trap density by charge blocking effect, which is confirmed by simulation results. However, the data retention characteristics show much less dependence on interface trap. Therefore, to improve SANOS memory characteristic, it is very important to optimize the interface trap and charge trapping layer.

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Investigation on the Rheological Properties of Coating Colors by immobilization cell (Immobilization cell을 이용한 도공액 특성 연구)

  • Park, Si-Han;Kim, Gyeong-Dong;Kim, Song-Ju;Heo, Yong-Seong
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2003.11a
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    • pp.139-147
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    • 2003
  • Coater runnability of the paper coating and final product properties can be affected by the immobilization of coating color and the dewatering into the base paper. During the dewatering, the rheological properties and solids content of a coating are dramatically changed. For the purpose of obtaining better coater runnability and high quality of coater paper many papermakers are trying to improve the water retention of paper coatings by using some additives such as thickener and co-binder. In this study, we tried to investigate the rheological properties and the immobilization point of coatings with immobilization cell during the dewatering of coatings.

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광합성세균에 의한 미생물막의 형성

  • Oh, Kwang-Keun;Lee, Cheol-Woo;Jeon, Yeong-Joong;Lee, Jae-Heung
    • Microbiology and Biotechnology Letters
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    • v.24 no.6
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    • pp.733-737
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    • 1996
  • The formation of microbial films(biofilm) by a non-sulfur phototrophic bacteria, Rhodopseudomonas capsulata, on inorganic media was studied. Porous ceramic beads(PCB) were superior to other immobilizing media for the biofilm formation in a packed-bed reactor. It was found that the formation of microbial films favored a lower hydraulic retention time, showing a higher ratio of cells attatched to the media to those suspended in the solution. The cell concentration in the biofilm reactor was as high as 11,400mg/l, which is 8-folds of the cell concentration in an ordinary suspended treatment. It was observed that the formation of micribial film by R. capsulata followed a general serial process of cell attachment, microcolony formation, and biofilm formation. The microbial films thus formed was very stable even for an extremely high volumetric BOD loading rate of 15gBOD/l day. The scanning electron micrographs of the microbial films showed that the cells were attached to both the surface and pores of the media.

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Flexible Display Device with Organic Composite Film

  • Choi, Yang-Kyu;Yarimaga, Oktay;Kim, Tae-Won;Jung, Yun-Kyung;Park, Hyun-Gyu
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1233-1236
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    • 2008
  • This study presents the fabrication process and display characteristics of a flexible organic polymer display device that consists of a thin substrate of Polyether Sulfone, a multilayer serpentine-type microheater array that is fabricated on the substrate, and a UV-sensitive polydiacetylene (PDA)-polyvinyl alcohol (PVA) composite film. A retention time of one second is achieved with cell sizes of $500{\mu}m$ and $700{\mu}m$ with cell-to-cell distances of $100{\mu}m$ and $200{\mu}m$, respectively.

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Development of multi-cell flows in the three-layered configuration of oxide layer and their influence on the reactor vessel heating

  • Bae, Ji-Won;Chung, Bum-Jin
    • Nuclear Engineering and Technology
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    • v.51 no.4
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    • pp.996-1007
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    • 2019
  • We investigated the influence of the aspect ratio (H/R) of the oxide layer on the reactor vessel heating in three-layer configuration. Based on the analogy between heat and mass transfers, we performed mass transfer experiments to achieve high Rayleigh numbers ranging from $6.70{\times}10^{10}$ to $7.84{\times}10^{12}$. Two-dimensional (2-D) semi-circular apparatuses having the internal heat source were used whose surfaces of top, bottom and side simulate the interfaces of the oxide layer with the light metal layer, the heavy metal layer, and the reactor vessel, respectively. Multi-cell flow pattern was identified when the H/R was reduced to 0.47 or less, which promoted the downward heat transfer from the oxide layer and possibly mitigated the focusing effect at the upper metallic layer. The top boundary condition greatly affected the natural convection of the oxide layer due to the presence of secondary flows underneath the cold light metal layer.

Prostate spindle cell neoplasm associated with early voiding difficulty after transurethral resection of the prostate

  • Chang Lim Hyun;Jung Sik Huh;Kyung Kgi Park
    • Journal of Medicine and Life Science
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    • v.20 no.2
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    • pp.94-98
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    • 2023
  • This report presents the case of 75-year-old men with spindle cell neoplasm. The patient underwent percutaneous nephrolithotomy and transurethral resection of the prostate (TURP) for renal stones and benign prostatic hyperplasia. One month postoperatively, the patient was able to void without any difficulty. Five months later, the patient experienced difficulty voiding and presented to the emergency room with severe pelvic pain. Computed tomography (CT) showed regrowth of the prostate mass into the posterior bladder and penile root. The prostate-specific antigen level remained constant at 1.14 ng/mL during the pre-and postoperative periods. Five months before the TURP operation, the patient's CT scan showed a soft and mildly enlarged prostate with no protrusion into the bladder. Biopsy of the prostate, however, showed a protruding mass, indicative of a spindle cell neoplasm. The patient was subsequently treated with the chemotherapeutic drug adriamycin. Unfortunately, treatment was unsuccessful, and the patient died 18 months later.

Change in Cell Size and Buoyant Density of Pseudomonas diminuta in Response to Osmotic Shocks

  • Lee, So-Hee;Cho, Yu-Ree;Choi, Yong-Jin;Kim, Chan-Wha
    • Journal of Microbiology and Biotechnology
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    • v.11 no.2
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    • pp.326-328
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    • 2001
  • Pseudomonas diminuta (ATCC 19146) has been typically used in the bacterial challenge test for validation of the sterilizing filtration process. Cell size is critical for determining the retention characteristics of membrane filters with pore-size of $0.2{\mu}m$. The changes of cell sizes after osmotic shocks at 150, 260, 500, and 700 mosM were measured by a particle size analyzer and the changes of their buoyant densities were analyzed with a Percoll gradient. The results indicated that there were no significant differences when cells were cultured in 260 mosM medium and osmotically shocked at 500 and 700 mosM. However, the osmotically shocked cells at 150 mosM showed a 38% increase of the cell size compared to the cells at 260 mosM. From these study, we concluded that the worst case condition for validation of a sterilizing filter would be 500 mosM, not because of changes in the cell size, but due to decrease in cell viability under those conditions.

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Effects of Direct Cell Contact Between Monocytes and Fibroblasts on the Interleukin-6 Production and Cell Proliferation of Human Gingival and Peri - odontal Ligament Fibroblasts (치은섬유아세포와 치주인대섬유아세포의 interleukin-6 분비 및 세포성장에 미치는 단핵구세포주와 섬유아세포의 세포간 접촉작용)

  • Kim, Soo-Ah;Lee, Ho;Kim, Hyung-Seop;Oh, Kwi-Ok
    • Journal of Periodontal and Implant Science
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    • v.29 no.4
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    • pp.803-823
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    • 1999
  • In order to reveal immunopathogenesis of periodontal tissue destruction, it is important to clarify the molecular mechanism of trafficking and retention of activated leukocytes, including monocytes/macrophages. Gingival fibroblasts may be involved in the regulation of inflammatory cell accumulation in the extravascular periodontal connective tissues via cytokine production and surface expression of adhesion molecules. In this study, it was investigated the molecular basis for the adhesive interactions between monocytes and fibroblasts such as peri-odontal ligament fibroblast(PDLF), human gingival fibroblast(HGF), and human dermal fibroblast(HDF). First, it was examined the evidence whether monocyte-fibroblast cell contact may cause signal transduction in fibroblasts. Being directly in contact with fixed human monocyte cell line THP-1, or U937, upregulation of IL-6 production, $TNF-{\alpha}$ mRNA expression and increased cell proliferation could be seen for fibroblasts. IL-6 production induced by monocyte- fibroblast coculture were further increased when fibroblasts had been pretreated with $IFN-{\gamma}$ or $IL-1{\beta}$ , and monocytes with LPS. Next, it was examined the expression of ICAM-1 which has been known to be involved in accumulation and activation of leukocytes in inflammatory diseases such as periodontitis. ICAM-1 was upregulated up to 10-fold on PDLF, HGF, and HDF by exposure to $IFN-{\gamma}$ or $IL-1{\beta}$. Furthermore, anti-ICAM-1 monoclonal antibody clearly blocked cocultureinduced IL-6 production by fibroblasts, suggesting that $ICAM-1/{\beta}_2$integrin pathway is involved in periodontal fibroblastmonocyte interaction. Overall, these findings provide evidence that periodontal fibroblasts could be involved in the accumulation and retention of monocytes/macrophages in periodontal inflammatory lesion at least in part by ICAM-1 expression. In addition, periodontal fibroblast-monocyte interaction could cause activation signals in fibroblasts intracellularly which result in cytokine production and cell proliferation. Thus, periodontal fibroblasts are speculated to play an important role in immunoregulation and tissue destruction in chronic periodontal diseases by interaction with monocytes/macrophages.

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Effect on Gene Expression Profile of Rat Hippocampus Caused by Administration of Memory Enhancing Herbal Extract (육미지황탕가미방이 흰쥐의 기억능력과 중추신경계 유전자 발현에 미치는 영향)

  • Choi So Eop;Bae Hyun Su;Shin Min Kyu;Hong Moo Chang
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.5
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    • pp.1025-1034
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    • 2002
  • The herbal extract (YMT_02) is a modified herbal extracts from Yukmijihwang-tang (YMJ) to promote memory-enhancing. The YMJ extracts has been widely used as an anti-aging herbal medicine for hundred years in Asian countries. The purpose of this study is to; 1) quantitatively evaluate the memory-enhancing effect of YMT_02 by behavior task, 2) identify candidate genes responsible for enhancing memory by cDNA microarray and 3) assess the anti-oxidant effect of YMT_02 on PC12 cell. Memory retention abilities are addressed by passive avoidance task with Sprague-Dawley (SD) male rat. Before the training session, the rats are subdivided into four groups and administrated with YMT_02, Ginkgo biloba, Soya lecithin and normal saline for 10 days. The retention test was performed. 24 hours after the training session. The retention time of the YMT_02 group was significantly (p<0.05) delayed (~100%), whereas Ginkgo biloba and Soya lecithin treatment delayed 20% and 10% respectively. The hippocampi of YMT_02 and control group were dissected and mANA was further purified. After synthesizing cDNA using oligo-dT primer, the cDNA were applied to Incyte rat GEMTM 2 cDNA microarray. The microarray results show that prealbumin(transthyretin), phosphotidylethanolamine N-methyltransferase, and PEP-19 are expressed abundantly in the YMT_02 treated group. Especially, PEP-19 is a neuron-specific protein, which inhibits apoptotic processes in neuronal cell. On the other hand, transcripts of RAB15, glutamate receptor subunit 2 and CDK108 are abundant in control group. Besides, neuronal genes involved in neuronal death or neurodegeneration such as neuronal-pentraxin and spectrin are abundantly expressed in control group. Additionally, the YMT_02 shows an anti oxidative effect in the PC12 cell. The list of differentially expressed genes may implicate further insight on the action and mechanism behind the memory-enhancing effect of herbal extracts YMT_02, for example, anti-apoptotic, anti-oxidative, and neuroprotective effects.

Nitrogen Utilization of Cell Mass from Lysine Production in Goats

  • Seo, S.;Kim, H.J.;Lee, S.Y.;Ha, Jong K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.4
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    • pp.561-566
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    • 2008
  • Two experiments were conducted to evaluate nutritive value of cell mass from lysine production (CMLP) as a protein supplement for ruminants. In each experiment, animals were fed a diet containing 40% of forages and 60% of concentrates, mainly composed of rice straw and ground corn, respectively, to meet the maintenance requirements, and the diets were formulated to supply equal amounts of energy and nitrogen among treatments. In order to investigate the effect of CMLP on ruminal fermentation (Experiment 1), three Korean native goats weighing $26.1{\pm}1.4kg$ were allotted into individual cages with a $3{\times}3$ Latin square design. Each animal was fed one of three protein sources (CMLP, soybean meal (SBM), and urea). Rumen pH, bacterial and fungal counts, volatile fatty acid concentrations and acetate to propionate ratio were not significantly different among treatments. Concentration of propionate, however, was higher in SBM treatment (14.1 mM) than in CMLP (8.7 mM) or urea (9.3 mM) treatments. There was significantly more branch-chain volatile fatty acid production in CMLP (1.9 mM) and SBM (1.8 mM) treatments than in urea (1.3 mM) treatment. The number of protozoa was the highest in urea treatment, followed by CMLP and SBM treatment with significant differences. A metabolic trial (Experiment 2) was conducted to measure in vivo nutrient digestibility and nitrogen retention in Korean native goats fed CMLP and SBM. Two heavy ($35.0{\pm}1.2kg$) and two light ($25.0{\pm}0.9kg$) Korean native goats, caged individually, were used in this experiment. A heavy and a light animal were paired and supplemented with either CMLP or SBM. The animals fed CMLP showed a trend of lower total tract digestibility in all the nutrients measured; however, there was no statistical significance except for digestibility of ether extract. Nitrogen digestibility of CMLP was estimated to be about 7% units lower than that of SBM. There was a tendency for lower nitrogen retention in CMLP treatment (35.9%) compared to SBM treatment (42.3%). In summary, CMLP can be a good protein source for ruminant animals from nutritional and economic perspectives and may replace some, if not all, of SBM in a diet without losing nitrogen utilization efficiency. Further research is warranted for investigating the effect of CMLP fed with easily fermentable forage and the effective level of CMLP for replacing SBM.