• Title/Summary/Keyword: cell area

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Squamous cell carcinoma of the skin in an Australian shepherd dog (개에서 피부 편평상피세포암의 발생과 치료 예)

  • 권오덕
    • Korean Journal of Veterinary Service
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    • v.24 no.1
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    • pp.101-107
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    • 2001
  • Squamous cell carcinoma of the skin was diagnosed in an 11-year-old, Australian shepherd dog with a hard mass on the right rump area. On histopathological examination of the tumor showed laminated keratin "pearls" surrounded by proliferated squamous cells, and mitotic figures. The dog was treated by surgical excision and chemotherapy with vinblastine sulfate, cyclophosphamide and prednisolone for 4 weeks. The tumor was effectively treated with a combination of surgery and chemotherapy.motherapy.

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Effect of operating temperature using Ni-Al-$ZrH_2$ anode in molten carbonate fuel cell (Ni-Al-$ZrH_2$ 연료극을 사용한 용융탄산염 연료전지의 온도의 영향)

  • Seo, Dongho;Jang, Seongcheol;Yoon, Sungpil;Nam, Suk Woo;Oh, In-Hwan;Lim, Tae-Hoon;Hong, Seong-Ahn;Han, Jonghee
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.134-134
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    • 2010
  • Fuel cell is a device that directly converts chemical energy in the form of a fuel into electrical energy by way of an electrochemical reaction. In the anode for a high temperature fuel cell, nickel or nickel alloy has been used in consideration of the cost, oxidation catalystic ability of hydrogen which is used as fuel, electron conductivity, and high temperature stability in reducing atmosphere. Most MCFC stacks currently operate at an average temperature of $650^{\circ}C$. There is some gains with decreased temperature in MCFC to diminish the electrolyte loss from evaporation and the material corrosion, which could improve the MCFC life. However, operating temperature has a strong related on a number of electrode reaction rates and ohmic losses. Baker et al. reported the effect of temperature (575 to $650^{\circ}C$). The rates of cell voltage loss were 1.4mV/$^{\circ}C$ for a reduction in temperature from 650 to $600^{\circ}C$, and 2.16mV/$^{\circ}C$ for a decrease from 600 to $575^{\circ}C$. The two major contributors responsible for the change in cell voltage with reducing operation temperature are the ohmic polarization and electrode polarization. It appears that in the temperature range of 550 to $650^{\circ}C$, about 1/3 of the total change in cell voltage with decreasing temperature is due to an increase in ohmic polarization, and the electrode polarization at the anode and cathode. In addition, the oxidation reaction of hydrogen on an ordinary nickel alloy anode in MCFC is generally considered to take place in the three phase zone, but anyway the area contributing to this reaction is limited. Therefore, in order to maintain a high performance of the fuel cell, it is necessary to keep this reaction responsible area as wide as possible, that is, it is needed to keep the porosity and specific surface area of the anode at a high level. In this study effective anodes are prepared for low temperature MCFC capable of enhancing the cell performance by using zirconium hydride at least in part of anode material.

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Life Cycle Analysis of Stem Cell Technology Based on Diffusion Model : Focused on the Research Stage (확산 모형을 이용한 줄기 세포 기술의 수명 주기 분석 : 연구 단계를 중심으로)

  • Jang, In-young;Hong, Jungsik;Kim, Taegu
    • Journal of Korean Institute of Industrial Engineers
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    • v.41 no.5
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    • pp.488-498
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    • 2015
  • Research on stem cells can be divided into three categories : pluripotent stem cell, adult stem cell, and induced pluripotent stem cell. Technology life cycle (TLC) on research stage is analyzed for the three stem cell categories based on diffusion model. Three diffusion models-logistic, Bass, and Bass model with integration constant (BMIC)-are applied to the number of articles related to each stem cell category in SCOPUS lists. Two different parameter estimation methods is used for each of logistic and Bass model. Results show that (1) the current year, 2015, lies in growth period at pluripotent stem cell and adult stem cell, and lies in growth period or maturity period at induced pluripotent stem cell. (2) Model fitness is the highest at BMIC model. (3) Imitation effect works best at the research area of induced pluripotent stem cell.

Morphology and Histochemistry of the Skin of the Mud Loach, Misgurnus mizolepis, in Relation to Cutaeneous Respiration

  • Park, Jong-Young;Kim, Ik-Soo;Kim, So-Young
    • Animal cells and systems
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    • v.5 no.4
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    • pp.303-308
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    • 2001
  • The skin structure of Misgurnus mizolepis was studied based on the microanatomical investigation of skin fragments taken from four regions. The epidermis was distinguished by two types of skin glands, a small mucous cell and a large club cell. The mucous cell was acid sulfomucins (some sialomucins) but the club cell did not give any histochemical tests for mucosubstances. The presence of a well defined lymphatic system with small lymphocytes was established in the stratum germinativum layer of the epidermis. A large number of blood capillaries run very close to each other just below the basement membrane, and a definite area giving AB and PAS positive was present between the basement membrane and scale. These structural features of skin in M. mizolepis seem to be closely related with cutaneous respiration.

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Electric-field induced si-graphene heterostructure solar cell using top gate

  • Won, Ui-Yeon;Yu, U-Jong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.287.2-287.2
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    • 2016
  • Silicon has considerably good characteristics on electron, hole mobility and its price. With 2-D sinlge-layer Graphene/n-Si heterojunction solar cell shows that in one sun condition exhibit power conversion efficiency(PCE) of 10.1%. This photovoltaic effect was achieved by applying gate voltage to the Schottky junction of the heterostructure solar cell. Energy band diagram shows that Schottky barrier between Si and graphene can be adjust by the external electric field. because of the fermi level of the graphene can be changed by external gate voltage, we can control the Schottkky barrier of the heterostructure solar cell. The ratio between generated power of solar cell and consumption electrical power is remarkable. Since we use the graphene as the top gate electrode, most of the sun light can penetrate into the active area.

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Improvement of Hydrocarbon Recovery by Two-Stage Cell-Recycle Extraction in the Cultivation of Botryococcus braunii

  • An, Jin-Young;Sim, Sang-Jun;Kim, Byung-Woo;Lee, Jin-Suk
    • Journal of Microbiology and Biotechnology
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    • v.14 no.5
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    • pp.932-937
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    • 2004
  • In situ extraction by organic solvent was studied in order to improve the recovery yield of hydrocarbon from the culture of Botryococcus braunii, a green colonial microalga. When the solvent mixture of octanol as an extractive solvent and n-octane as a biocompatible solvent was added to a two-phase column, the algal growth was seriously inhibited, even at a low concentration of polar octanol. Therefore, a two-stage cell-recycle extraction process was proposed to improve the contact area between the organic phase and the aqueous phase. The hydrocarbon recovery with in situ cell-recycle extraction showed a three-fold increase (57% of cell) in yield over that with two-phase extraction. In addition, over 60% of the hydrocarbon could be recovered without serious cell damage by downstream separation when this process was applied to the culture broth after batch fermentation.

Metal-assisted grown Si films and semiconducting nanowires for solar cells

  • Kim, Jun-Dong
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2010.05a
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    • pp.13-13
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    • 2010
  • The solar energy conversion will take 10 % global energy need by 2033. A thin film type solar cell has been considered as one of the promising candidates for a large area applicable solar cell fabrication at a low cost. The metal-assisted growth of microcrystalline Si (mc-Si) films has been reported for a quality Si film synthesis at a low temperature. It discusses the spontaneous growth of a Si film above a metal-layer for a thin film solar cell. Quite recently, a substantial demand of nanomaterials has been addressed for cost-effective solar cells. The nanostructure provides a large photoactive surface at a fixed volume, which is an advantage in the effective use of solar power. But the promising of nanostructure active solar cell has not been much fulfilled due mainly to the difficulty in architecture of nanostructures. We present here the Si nanowire (SiNW)-embedded Schottky solar cell. Multiple SiNWs were connected to two different metals to form a Schottky or an ohmic contact according to the metal work function values. It discusses the scheme of rectifying contact between metals and SiNWs and the SiNW-embedded Schottky solar cell performances.

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EXPRESSION OF DOMINANT NEGATIVE p63 ISOFORM IN WELL-DIFFERENCIATED ORAL SQUAMOUS CELL CARCINOMA (분화도 좋은 구강 편평상피세포암종에서 Dominant Negative p63 isoform의 발현)

  • Kim, In-Su;Kim, Chul-Hwan;Kim, Kyung-Wook
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.3
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    • pp.191-198
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    • 2007
  • The p53 which is well known as tumor suppressor gene is located at 17p13. p53 is a sequence-specific DNA binding transcription factor that responds to certain cytotoxic stresses, such as DNA damage, by enhancing the transcription of genes that regulate cell-cycle progression as well as programmed cell death. The p63 gene that is located at 3q27-29, is recognized members of the p53 family, and responsible for the transcription of 6 isoforms. Three isoforms ($TAp63{\alpha}$, $TAp63{\beta}$, $TAp63{\gamma}$) contain an N-terminal transactivation (TA) domain and can induce apoptosis. The other 3 isoforms (${\Delta}Np63{\alpha}$, ${\Delta}Np63{\beta}$, ${\Delta}Np63{\gamma}$) lack the TA domain and may function in a dominant-negative fashion by inhibiting the transactivation functions of p53 and TAp63 proteins, and thus act as oncoproteins. A number of studies have investigated the role of p63 in human squamous cell carcinomas from different organs. Only a few studies have examined ${\Delta}Np63$ isoform in oral squamous cell carcinoma including normal epithelium. This study aimed to evaluate expression of ${\Delta}Np63$ isoform in human oral squamous cell carcinoma tissue and normal mucosa. The 3 cases of well differenciated oral squamous cell carcinoma specimen including adjacent normal mucosa were examined, and immunohistochemical study with monoclonal antibody(4A4) and tumor cell apoptosis analysis with Transmission Electon Microscopy were studied. And, RT-PCR analysis was done for expression of ${\Delta}Np63$ isoform. The results were as followed. 1. Normal gingiva showed the restricted p63 expression in basal cell layer. 2. Well differentiated squamous cell carcinoma showed mainly p63 expression in overall area of malignancy, especially in basal cell layer to adjacent stromal tissue. 3. Tumor cells around keratinized area with no p63 expression disclosed less micro-organelle in decreased size cytoplasm and severe chromatin margination with nuclear destruction that means apoptosis. 4. Comparison of mRNA expression of ${\Delta}Np63$ isoform by RT-PCR showed variable expression of ${\Delta}Np63$ isoform, but ${\Delta}Np63{\alpha}$ was most highly expressed in all 3 tumor specimen. From theses results, it should be suggested that ${\Delta}Np63$ isoform expression in well differentiated squamous cell carcinoma was closely related to tumor oncogenesis, expecially overexpression of ${\Delta}Np63{\alpha}$ is a most important factor in tumor genesis of oral squamous cell carcinoma.

Performance analysis of session admission control based on area for software download in cellular CDMA systems (셀룰러 CDMA 시스템에서 소프트웨어 다운로드를 위한 영역 기반 세션수락제어방식 성능분석)

  • 김광식;조무호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.5A
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    • pp.294-304
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    • 2003
  • For an efficient software download in cellular CDMA systems, session admission control based on area (SACA) is presented. In the SACA scheme, the base station only allows mobile terminal to start session when the mobile locates near the base station of a cell. A mobile that is located near cell center can request software download session, but the mobile that is far away from the center can request session only after arriving near the cell center. Session duration time follows exponential and Pareto distribution. Performance is analyzed in terms of handoff rate, mean channel holding time, session blocking probability and handoff forced termination probability. As analysis results, handoff rate between cells in the proposed scheme is reduced to 30 ~ 250 % compared to conventional scheme, according to traffic characteristics such as terminal speed, session duration time and the size of the allowable zone area in a cell for the start of the session. And new session blocking probability slightly decreases to 5 ~ 20 %, but handoff session forced termination probability drastically decreases to 35 ~ 220 %.

Cell Grouping Design for Wireless Network using Artificial Bee Colony (인공벌군집을 적용한 무선네트워크 셀 그룹핑 설계)

  • Kim, Sung-Soo;Byeon, Ji-Hwan
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.39 no.2
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    • pp.46-53
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    • 2016
  • In mobile communication systems, location management deals with the location determination of users in a network. One of the strategies used in location management is to partition the network into location areas. Each location area consists of a group of cells. The goal of location management is to partition the network into a number of location areas such that the total paging cost and handoff (or update) cost is a minimum. Finding the optimal number of location areas and the corresponding configuration of the partitioned network is a difficult combinatorial optimization problem. This cell grouping problem is to find a compromise between the location update and paging operations such that the cost of mobile terminal location tracking is a minimum in location area wireless network. In fact, this is shown to be an NP-complete problem in an earlier study. In this paper, artificial bee colony (ABC) is developed and proposed to obtain the best/optimal group of cells for location area planning for location management system. The performance of the artificial bee colony (ABC) is better than or similar to those of other population-based algorithms with the advantage of employing fewer control parameters. The important control parameter of ABC is only 'Limit' which is the number of trials after which a food source is assumed to be abandoned. Simulation results for 16, 36, and 64 cell grouping problems in wireless network show that the performance of our ABC is better than those alternatives such as ant colony optimization (ACO) and particle swarm optimization (PSO).