• Title/Summary/Keyword: plasma cells

Search Result 1,288, Processing Time 0.026 seconds

Identification and Characterization of Phytochrome-Regulated Phospholipase D in Oat Cells (Avena sativa L.)

  • Park, Cheon;Park, Moon-Hwan;Chae, Quae
    • BMB Reports
    • /
    • v.29 no.6
    • /
    • pp.535-539
    • /
    • 1996
  • The activation of phospholipase D (PLD) catalyzes hydrolysis of phosphatidylcholine (PC) to phosphatidic acid (PA) and choline in plants as well as animals. To determine the presence of PLD in oat cells, we prepared inside-out plasma membrane and cytosolic fractions from oat tissues. PLD activities in both cytosol and plasma membrane were detected by ion chromatography method. The activity of PLD in plasma membrane was dependent upon $Ca^{2+}$ concentration and was heat stable. To investigate whether G-protein couples to PLD, the effects of $GTP{\gamma}S$ and $GDP{\beta}S$ on the PLD activity were measured. PLD activity was dramatically increased 300~400% in the presence of 50 ${\mu}M$ $GTP{\gamma}S$ but not in the presence of 50 ${\mu}M$ $GDP{\beta}S$. These results indicate that G-protein may be involved in regulation of PLD activity. To identify whether PLD is regulated by red light receptor, phytochrome, we irradiated red, far-red, or red/far-red/red light on oat protoplasts. PLD activity has increased 5-fold and 3-fold by treatment with red light and red/far-red/red light, respectively. In contrast, irradiation with far-red light had little or no effect on PLD activity. These results suggest that phytochrome regulates PLD activity through activation of G-protein in oat cells.

  • PDF

Enviromental Application of Plasma Technology

  • Lee, Won-Ju
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.119.1-119.1
    • /
    • 2014
  • Toxic waste disposal: Many people think that when toxic waste is dumped into the ocean or into the air, it disappears. This belief is incorrect. Rather than disappearing, it accumulates over time and slowly destroys the environment. Ultimately, it leads to the destruction of human race. Plasma is environmentally friendly: Plasma is environmentally friendly because it is created and disappears. When plasma is formed on the earth, you need certain conditions such as accelerating electrons by an electrical discharge or a particle accelerator. When this is gone, plasma completely disappears, leaving no impact on the environment. Plasmas produce radicals: Even if plasma density is low at atmospheric pressure, many radicals (excited states of molecules) are created. These radicals are chemically very aggressive. So instead of using harmful chemicals, plasma can be utilized for less of an impact on the environment. Plasma can reach very high temperatures: Plasma is also useful because when you control the density, you can easily reach high temperatures up to $5000{\sim}6000^{\circ}C$ at atmosphere pressure. Because of this heat and the chemical aggressiveness of the plasma, there are many green applications for plasma technology. Pulsed power technology: Pulsed electric field for extraction, drying and killing bacteria. Treatment of biological tissue by pulsed electric fields: Extraction of substances from cells: Sterilisation, Medical applications, Growth stimulation, Food preparation. Each application has its specialities, especially with respect to pulse shape and electric field strength.

  • PDF

STUDY ON THE IMPROVEMENT OF LIGHT TRAPPING IN THE SILICON-BASED THIN-FILM SOLAR CELLS (실리콘 박막 태양전지에서 광 포획(light trapping) 개선에 관한 연구)

  • Jeon Sang Won;Lee Jeong Chul;Ahn Sae Jin;Yun Jae Ho;Kim Seok Ki;Park Byung Ok;Song Jinsoo;Yoon Kyung Hoon
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.192-195
    • /
    • 2005
  • The silicon thin film solar cells were fabricated by 13.56 MHz PECVD (Plasma-Enhanced Chemical-Vapor Deposition) and 60 MHz VHF PECVD (Very High-Frequency Plasma-Enhanced Chemical-Vapor Deposition). We focus on textured ZnO:Al films prepared by RF sputtering and post deposition wet chemical etching and studied the surface morphology and optical properties. These films were optimized the light scattering properties of the textured ZnO:Al after wet chemical etching. Finally, the textured ZnO:Al films were successfully applied as substrates for silicon thin films solar cells. The efficiency of tandem solar cells with $0.25 cm^2$ area was $11.8\%$ under $100mW/cm^2$ light intensity. The electrical properties of tandem solar cells were measured with solar simulator (AM 1.5, $100 mW/cm^2)$ and spectral response measurements.

  • PDF

Studies on Transport Mechanisms of Turtle Bladder I . Epithelium of Urinary Bladder (Turtle bladder의 수송기작(輸送機作)에 관한 연구 : I. 방광(膀胱)의 상피조직(上皮組織))

  • Jeon, Jin-Seok
    • Applied Microscopy
    • /
    • v.19 no.2
    • /
    • pp.119-137
    • /
    • 1989
  • It has been shown in this and earlier investigation that the turtle bladder mucosa has three main cell types on their mucosal surface. They are the granular cells, ${\alpha}$ CA cells, and ${\beta}$ CA cells. The three major transport mechanisms that occurs in the turtle bladder are sodium reabsorption, proton secretion, and bicarbonate secretion. In the present work the trans-port mechanisms by bladder epithelial cells of freshwater turtle, Pseudemys scripta, are summarized as follows. 1. The granular cells play an important role in sodium transport, while the ${\alpha}$ and ${\beta}$ CA cells do not appear to play a determining role in sodium transport. 2. It appears that the active sodium transport in the granular cells occurs in two-step process, implying that first, sodium diffuses into the cells, followed by an energy-dependent efflux step, which is catalyzed by the ouabain-sensitive Na-K ATPase. 3. The ${\alpha}$ type of CA cells are responsible for the proton secretion using the proton pump on the apical plasma membrane, while the ${\beta}$ type of CA cells are believed to be responsible for bicarbonate secretion. 4. When looked at under freeze-fracture electron microscopy, the apical plasma membrane of ${\alpha}$ cells have a characteristic population of rod-shaped intramembranous particles which are believed to be components of the proton pumps. Conversely, ${\beta}$ type of CA cells show rod-shaped particles in their basolateral plasma membranes, which is consistent with the proton absorptive, bicarbonate secretory mechanism. 5. In the turtle bladder, the ${\alpha}$ and ${\beta}$ type of cells are believed to be both responsible for proton transport, but in opposite directions.

  • PDF

The effect of RF electric fields from an atmospheric micro-plasma needle device on the death of cells (침형 상압 마이크로 플라즈마 장치에서 발생하는 전기장이 세포 사멸에 미치는 효과)

  • Yoon, Hyun-Jin;Shon, Chae-Hwa;Kim, Gyoo-Cheon;Lee, Hae-June
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.57 no.12
    • /
    • pp.2249-2254
    • /
    • 2008
  • A non-thermal micron size plasma needle is applicable for medical treatment because it includes radicals, charged particles, ultraviolet emission, and strong electric fields. The electric fields around the plasma needle device driven by a radio frequency wave are investigated in order to calculate the power delivered to the cell. A commercial multi-physics code, CFD-ACE, was utilized for the calculation of electric fields for the optimization of the needle structure. The electric field and energy absorption profiles are presented with the variation of the device structure and the distance between the needle and tissues. The living tissues effectively absorb the radio frequency power from the plasma needle device with the covered pyrex structure.

The study on the electrical and optical characteristics of a new structure for color ac plasma displays (새로운 전극구조를 가진 ac-PDP의 전기 광학적 특성에 관한 연구 (II))

  • Ko, Ji-Sung;Lee, Woo-Geun;Lee, Jae-Young;Park, Jae-Moon;Cho, Jung-Soo;Park, Chung-Hoo
    • Proceedings of the KIEE Conference
    • /
    • 1999.07e
    • /
    • pp.2230-2232
    • /
    • 1999
  • A new type ac plasma display panel(PDP) cells are designed and tested electrically and optically. One cell has the structure of sin discharge path shape and small electrode area. The other cells have the non-symmetric structure with a same electrode area. They show a higher luminous efficienccy and a lower power consumption about 25% improvement than the conventional standard ac PDP cells.

  • PDF

Improvement of the Accuracy of Optical Simulation Using by the Multi-cube UV Source in PDP Cells (Multi-cube UV source 이용한 PDP에서 광학시뮬레이션의 정확성 개선에 관한 연구)

  • Kang, Jung-Won;Eom, Chul-Whan
    • Journal of the Semiconductor & Display Technology
    • /
    • v.6 no.2 s.19
    • /
    • pp.41-44
    • /
    • 2007
  • Optical simulation of the rear and front panel geometries were needed to improve the luminance and efficiency in PDP cells. The 3-dimensional optical code can be used to analyze the variation of geometries and changing of optical properties. In order to improve the accuracy of simulated results, a new UV source, called a multi-cubes UV source, was designed. To design the source, at first UV distribution was calculated with the plasma fluid code and then the UV distribution was transformed to the multi-cube structures in the optical code. Compared to the results from existing UV source, called a planar UV source, could be improved the accuracy of visible light distribution. Simulated results were also compared to the visible distribution measured with the ICCD in a real PDP cell.

  • PDF

Sputter Deposition and Surface Treatment of $TiO_{2}$ films for Dye-Sensitized Solar Cells using Reactive RF Plasma (RF 스퍼터링 증착된 $TiO_{2}$ 박막의 염료감응형 태양전지 적용 연구)

  • Kim, Mi-Jeong;Seo, Hyun-Woong;Choi, Jin-Young;Jo, Jae-Suk;Kim, Hee-Je
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2007.06a
    • /
    • pp.309-312
    • /
    • 2007
  • Sputter deposition followed by surface treatment was studied using reactive RF plasma as a method for preparing titanium oxide($TiO_{2}$) films on indium tin oxide(ITO) coated glass substrate for dye-sensitized solar cells(DSSCs). Anatase structure $TiO_{2}$ films deposited by reactive RF magnetron sputtering under the conditions of $Ar/O_{2}$(5%) mixtures, RF power of 600W and substrate temperature of $400^{\circ}C$ were surface-treated by inductive coupled plasma(ICP) with $Ar/O_{2}$ mixtures at substrate temperature of $400^{\circ}C$, and thus the films were applied to the DSSCs, The $TiO_{2}$ Films made on these exhibited the BET specific surface area of 95, the pore volume of $0.3cm^{2}$ and the TEM particle size of ${\sim}25$ nm. The DSSCs made of this $TiO_{2}$ material exhibited an energy conversion efficiency of about 2.25% at $100mW/cm^{2}$ light intensity.

  • PDF

Plasma Textured Glass Surface Morphologies for Amorphous Silicon Thin Film Solar Cells-A review

  • Hussain, Shahzada Qamar;Balaji, Nagarajan;Kim, Sunbo;Raja, ayapal;Ahn, Shihyun;Park, Hyeongsik;Le, Anh Huy Tuan;Kang, Junyoung;Yi, Junsin;Razaq, Aamir
    • Transactions on Electrical and Electronic Materials
    • /
    • v.17 no.2
    • /
    • pp.98-103
    • /
    • 2016
  • The surface morphology of the front transparent conductive oxide (TCO) films plays a vital role in amorphous silicon thin film solar cells (a-Si TFSCs) due to their high transparency, conductivity and excellent light scattering properties. Recently, plasma textured glass surface morphologies received much attention for light trapping in a-Si TFSCs. We report various plasma textured glass surface morphologies for the high efficiency of a-Si TFSCs. Plasma textured glass surface morphologies showed high rms roughness, haze ratio with micro- and nano size surface features and are proposed for future high efficiency of a-Si TFSCs.

Ultrastructure of the Rectum Epithelial Cells in the Mosquito Larvae, Culex pipiens pallens (빨간집모기 유충 내에 있는 직장 상피세포들의 미세구조)

  • Yu, Chai-Hyeock
    • Applied Microscopy
    • /
    • v.29 no.2
    • /
    • pp.223-230
    • /
    • 1999
  • The epithelium of the rectum in the mosquito larvae, Culex pipiens pallens: Culicidae, was observed with electron microscope. The rectum of posterior hindgut was composed of epithelial tissue which were covered with cuticular intima on the luminal side, connective tissue and muscular tissue. The rectal epithelial cells were squamous absorptive cells, and apical plasma membranes were highly folded to form apical infoldings with mitochondria inserted them. The lateral plasma membranes were irregularly infolded and well developed mitochondria were found closely associated with infoldings . And intercellular spaces (or channels) were formed between the epithelial cells, whereas speptate junction was found near the apical zone between them. Also basal plasma membrane were infolded which made basal infoldings ('basal labyrinth'), and were covered with thin basal lamina. Rcetal epithelium was surrounded by the connective tissue which was contained axon and tracheole cells. Connective tissue was covered with the bundles of circular and longitudinal muscles.

  • PDF