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Sample records for cell nenryo denchi

  1. Fuel cell power generation facility; Nenryo denchi hatsuden sochi

    Energy Technology Data Exchange (ETDEWEB)

    Hara, T.; Kato, K. [Aishin AW Co. Ltd., Aichi (Japan); Tanizaki, K.; Ishiko, C. [Equos Research Co. Ltd., Tokyo (Japan)

    1996-07-12

    In a fuel cell power generation facility with a carbon monoxide removal equipment to remove carbon monoxide in a reformed gas by oxidation, a reversed flow of the residual reformed gas in the reformed gas feeding line to the fuel reforming equipment cannot be prevented by a previous suspension technique. This invention aims to present a method to prevent a reversed flow of the residual reformed gas and to protect effectively the fuel cell power generation facility against the danger of catching fire or explosion. This invention relates to a fuel cell power generation facility installed with a fuel reforming equipment and a carbon monoxide removal equipment to remove carbon monoxide in the reformed gas by oxidation, which is equipped with reversed flow prevention devices on the oxidizer gas feeding duct to the carbon monoxide removal equipment, on the reformed gas feeding duct from the fuel reforming equipment to the carbon monoxide removal equipment and on the source fuel feeding duct to the fuel reforming equipment. The reversed flow prevention devices are made of direction control valves or pressure control valves. 2 figs.

  2. Electrolyte for phosphoric acid fuel cell. Rinsangata nenryo denchi no denkaieki

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Y.; Uede, M.; Yamaken, H. (Yamaha Motor Co. Ltd., Shizuoka (Japan))

    1991-02-14

    When the phosphoric fuel cell is used in cold districts, the electrolyte used in the cell solidifies and freezes because its freezing point is high, and the cell can not be used any more. The object of this invention is to provide a fuel cell which does not freeze even the cell is shutdown in low temperature environment by adding non-conjugating inorganic salt to strong phosphoric acid to lower the freezing point. The phosphoric acid used in accordance with this invention is desirable generally to be of 80 to 105% if calculated in terms of orthophosphoric acid to maintain the cell performance. As the negative ions constituting the non-conjugating inorganic salt, sulphate ion, carbonate ion, silicate ion, and boric acid ion are desirable. In concrete, ZnSO{sub 4}, NiSO{sub 4}, Na{sub 2}SO{sub 4}, BeSO{sub 4}, CdSO{sub 4}, CoSO{sub 4}, FeSO{sub 4}, K{sub 2}CO{sub 3}, Na{sub 2}CO{sub 3}, CaCO{sub 3}, MgCO{sub 3}, K{sub 2}SiO{sub 3}, Na{sub 2}B{sub 4}O{sub 7}, etc. can be quoted. Excessive addition of inorganic salt results rather in the precipitation of the added inorganic salt to cause freezing, and addition of 20wt% or less is desirable. 1 fig.

  3. Development of an overall technology for phosphoric acid fuel cells. ; Research and development of a fuel cell power generation system for business use. Rinsangata nenryo denchi no sogoteki gijutsu kaihatsu. ; Gyomuyo nenryo denchi hatsuden system no kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This paper reports the research and development work on a fuel cell power generation system using phosphoric acid fuel cells for business use. The system researches have included pre-investigation on loads, and discussions on methods to recover heat generated from fuel cells, a performance test, an actual load test, and a trap test in the operational tests. High-temperature thermal output from the fuel cells will be used in a double-effect absorption water freezing/heating machine as a load for air conditioning of guest rooms in a hotel. Low-temperature thermal output will be connected to a part of the hot-water supply systems in a kitchen and guest rooms. The elementary researches have been performed for studies on fuel cell technologies and improvement of fuel cell characteristics. High-performance cooling technologies, reforming technologies, and inverter technologies have been studied, and the system for 100-kW class plant machines has been reviewed. The elementary researches have been used to execute a basic design for a 200-kW fuel cell power plant for business use. A high-performance turbine and a compressor have been developed. Developments have been made on tertiary system catalysts, and capacity increase in phosphoric acid storage system using separators with composite ribs as technologies for improving the fuel cell characteristics. 30 figs., 7 tabs.

  4. FY 1998 annual report on the development of fuel cell power generation techniques. Research and development of solid electrolyte fuel cells (research results); 1998 nendo nenryo denchi gijutsu kaihatsu. Kotai denkaishitsugata nenryo denchi no kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Described herein are the FY 1998 research and development results of solid electrolyte fuel cells. For R and D of the tubular type cell by the wet processing technique, the tests are conducted to evaluate the initial performance and long-term durability for continuous operation of the single tubular cell. For development of the several-kW class modules, computer-aided simulations are conducted. For R and D of material and substrate techniques, the thermal cycle characteristics, cell characteristics and stress of the cell modules are evaluated, in order to evaluate their reliability. The thermal cycle test results indicate that performance of the single-stage cell is unaffected by the thermal cycles. It is found by the stress evaluation that use of the separator plate having a higher thermal expansion coefficient than the electrolyte plate and use of the sealant having a thermal expansion coefficient close to that of the electrolyte plate are effective means to reduce stresses. For the research to reduce costs of the cell materials, their chemical, mechanical and thermal characteristics are evaluated. For the system research, the areas for which the compact systems are suitable and their optimization are studied. (NEDO)

  5. FY 1999 Report on research and development of power generation by solid electrolyte fuel cell. Research and development of solid electrolyte fuel cell; 1999 nendo nenryo denchi hatsuden gijutsu kaihatsu kotai denkaishitsugata nenryo denchi no kenkyu kaihatsu kenkyu seika

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-06-01

    This project is aimed at establishment of the module basic technology and commercialization of the solid electrolyte fuel cell in the early stage by designing, construction, operation and performance evaluation of a several kW-class module which incorporates the cylindrical cell fabricated by the wet process. The FY 1999 R and D efforts include (1) cell performance demonstration study: the cylindrical single cell fabricated by the wet process is demonstration-tested to determine the initial performance and durability for continuous operation, thereby comparing the external reforming with internal reforming in output, with the internal reforming rate as the parameter, (2) development of a several kW-class module: the adequate cell arrangement structure within the module is studied by the computer-aided simulation, and the tests for confirming thermal cycle durability of the modified bundle are conducted using the module power generation unit and the several kW-class module is tested, and (3) development of the technology for designing a thermally supported module: the effects of, e.g., air and fuel supply conditions on the module performance are analyzed using the analytical model as the base. Expansion of the module level to the process simulation model has been completed, based on these results. (NEDO)

  6. Guide to the effective use of cogeneration and fuel cell (Akita Prefecture); Cogeneration nenryo denchi katsuyo guide (Akitaken)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    General cogeneration and fuel cells are separately described in this guidebook. There is a view that a fuel cell is a highly efficient energy system in which both electric power and heat are effectively utilized, and it regards the fuel cell as representative of one of the utilization modes of cogeneration. Following this view, a fuel cell is given a position in parallel with general cogeneration. This guidebook expects that it will be read at private businesses and factories and various public departments within the prefecture where the introduction and utilization of general cogeneration and fuel cells are under study, and describes the procedures to follow when using the energy systems and names the offices to which the readers should refer as need arises. It also expects that people at large in the prefecture who are interested in general cogeneration and fuel cells will be among the readers, and various information is stated for them outlining the energy systems, explaining their merits, and mentioning cases of their application in the past. (NEDO)

  7. Activation method of the fuel electrode of a methanol fuel cell. Methanol nenryo denchi no nenryokyoku no kasseika hoho

    Energy Technology Data Exchange (ETDEWEB)

    Ozeki, H.; Tanizaki, K.; Dokoshi, H. (Aisin AW Co. Ltd., Aichi (Japan))

    1992-09-04

    It is known that, with the addition of 1-2% of oxygen to the fuel in a methanol fuel cell, carbon monoxide adsorbed on a platinum catalyst is oxidized to carbon dioxide, liberated from the platinum catalyst and exhausted from the fuel chamber. However, in this method, the efficiency of the fuel cell decreases because oxygen is always contained in the fuel and burnt directly in the fuel electrode. Moreover, in case platinum-ruthenium is used as a catalyst in the fuel electrode, the catalyst adsorbs oxygen very well and a small amount of hydrogen or oxygen should be supplied from the outside in order to activate the catalyst. The invention concerns an activation method of the oxygen-adsorbing fuel electrode of a methanol fuel cell, in which water in the electrolyte solution in the methanol fuel cell is eletrolyzed by the use of the fuel cell as a cathode with an external power supply so as to remove the oxygen adsorbed in the fuel electrode. 7 figs.

  8. FY 1993 report on the results of the commissioned research and development project. R and D of SOFC (solid oxide fuel cells); 1983 nendo nenryo denchi hatsuden gijutsu kaihatsu seika hokokusho. SOFC kotai denkaishitsugata nenryo denchi no kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-05-01

    The research and development project is carried out for fuel cell power generation technologies and solid electrolyte type fuel cells, and the reports on the FY 1993 results issued by the participant organizations are summarized. For R and D of the modules, Fuji Electric conducted the R and D for the large-area, cell-stacked type, and Sanyo Electric for the composite cell-stacked type. For R and D of the materials and fundamental technologies, Fine Ceramics Center conducted the R and D for microscopic structures of the electrode, Fujikura for electrode structures produced by spraying or the like, Mitsubishi Heavy Industries for multi-functional fuel electrodes, Murata Seisakusho for co-sintering technologies, and Mitsui Shipbuilding for current collecting technologies. For R and D of the systems, Central Research Institute of Electric Power Industry conducted the R and D for the systems, Electric Power Development and Mitsubishi Heavy Industries jointly for designs of the cell peripheries, and the Japan Research and Development Center for Metals for elementary technologies for the peripheral devices. (NEDO)

  9. Operating state distinction and operation control methods of the fuel cell stack; Nenryo denchi sutakku no unten jotai hanbetsu hoho oyobi unten seigyo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, M.; Nakajima, H.; Shiraishi, K. [Equosu Resarch Co. Ltd., Tokyo (Japan)

    1997-09-19

    In the operation of the fuel cell stack, output decrease is caused by surplus or deficient water content in part or whole of the fuel cell stack. The purpose of the invention is to provide operating state distinction and operation control methods, whereby the output abnormality is discovered in the early stage, and is quickly adjusted to the normal state. In accordance with the invention, time course voltage patterns of the cell block, composed of one or plural unit cells in the fuel cell stack that has solid oxide films as electrolytes, are classified by various operation conditions of the fuel cell, and stored in the memory in advance. Time course voltage patterns are measured by one unit cell or by the cell block; operation conditions are judged, compared and calculated while the measured time course voltage patterns and the patterns in the memory are compared; proper setting of operation conditions is selected; and command for adjusting to the setting is delivered to the unit cell or cell block in the fuel cell stack. 6 figs.

  10. FY 2000 report on the results of the R and D of solid oxide fuel cells (SOFC); 2000 nendo kotai denkaishitsugata nenryo denchi no kenkyu kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-05-01

    Development of fuel cell power generation technology and R and D of solid oxide fuel cells were carried out, and reports of the FY 2000 results of companies were summed up. As to the R and D of the cell module, the R and D on the wet type cylinder module were made jointly by Toto Ltd., Kyushu Electric Power Co. and Nippon Steel Corp. As to the R and D of materials/basic technology, the following were conducted: evaluation of reliability of the cell module (evaluation of thermal cycle characteristics, etc.) by Chubu Electric Power Co., evaluation of reliability of the cell module (cell characteristics/stress evaluation) by Tokyo Gas Co. Ltd., cost reduction of cell materials (evaluation of chemical characteristics) by Central Research Institute of Electric Power Industry, and cost reduction of cell materials (evaluation of mechanical/thermal characteristics) by Japan Fine Ceramics Center. Concerning the system study, study of the system (adaptation fields of the small system and the optimization) was conducted by Nippon Steel Corp. (NEDO)

  11. Hear recovery properties from fuel cell system for telecommunications use; Tsushin`yo nenryo denchi system no fuirudotesuto ni okeru hainetsu kaishu tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Ishizawa, M.; Iida, S.; Abe, I.; Amanuma, H. [NTT Integrated Information and Energy Systems Laboratories Tokyo (Japan); Uekusa, T.; Waragai, S. [NTT Power and Building Eacilities Inc., Tokyo (Japan)

    1997-12-20

    NTT is developing a phosphoric acid fuel cell energy system for telecommunication co-generation systems to reduce energy costs and help preserve the environment. Fuel cells are used to provide electrical power to telecommunication equipment and the heat energy that is generated is used by the absorption refrigerator to cool the telecommunication rooms throughout the year. We fieldtested this fuel cell energy system in a telephone office for three years. Heat recovered water from fuel cell stack coolant was supplied to the absorption refrigerator and further extra-heat was recovered by a heat exchanger. The toral heat recovery amount was about 86000 kca/h (the heat recovery efficiency was 20%) under 200kW operation. The absorption refrigerator was supplied about 49000kcal/h of heat and operated with 0.7 of coefficient of performance throughtout the year. The electrical efficiency was maintained more than 38% after 13000h operation. 12 refs., 10 figs., 3 tabs.

  12. Heat recovery properties from fuel cell system for telecommunications use; Tsushin`yo nenryo denchi system ni okeru hainetsu kaishu tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Ishizawa, M.; Iida, S.; Abe, I.; Yamamoto, M. [NTT Integrated Information and Energy Systems Laboratories, Tokyo (Japan)

    1997-08-20

    NTT is developing a phosphoric-acid fuel-cell energy system for telecommunication co-generation systems to reduce energy costs and help preserve the environment. Fuel cells are used to provide electrical power to telecommunication equipment and the heat energy that is generated is used by the absorption refrigerators to cool the telecommunication rooms throughout the year. We field-tested this fuel-cell energy system in a telephone office. Two heat recovery methods were applied in the test: one uses direct steam heat recovery from fuel-cell stack coolant to keep the heat recovery temperature high and to avoid requiring a heat exchanger for the recovery; the other uses heat recovery from the reformer exhaust gas that is directly in contact with the heat recovery water to recover heat more economically. Our field tests confirmed that the average efficiency of heat recovery from fuel-cell stack coolant is 16%, and from the reformer exhaust gas is 9% under 80-kW continuous operation. Maximum total efficiency including electrical power efficiency was confirmed to be about 73% under the condition of 100-kW and an S/C ratio of 2.5 in the winter period: heat recovery from the fuel-cell stack coolant was 23%, from the reformer exhaust gas was 10%, and from electrical conversion was about 40%. 9 refs., 12 figs., 1 tab.

  13. Achievement report for fiscal 1997 on research and development of solid electrolyte fuel cells; Kotai denkaishitsugata nenryo denchi no kenkyu kaihatsu 1997 nendo seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    This paper describes the achievements in fiscal 1997 on research and development of solid electrolyte fuel cells. Fuji Electric has demonstrated possibilities of film type cells of predominantly metallic flat plate supporting type of a large-area cell lamination system, and seal-less stack structure. Sanyo Electric has discussed making thinner the composite cell lamination type anode, optimization in sintering temperature, and sealing materials. The Fine Ceramic Center has performed a 1,000-hour test on an La(Sr) MnO{sub 3}-YSZ electrode, in which A-site defect amount was decreased to 0.1-0.02 to stabilize micro-structure air electrodes for an extended period of time. Fujikura has discussed functional materials for high dispersion and slanting in a fuel electrode Ni/YSZ. Mitsubishi Heavy Industries has fabricated MgO-based fuel electrodes on a trial basis, and performed internal reformation and power generation tests by using full-size stacks. Murata Manufacturing Company has verified long-term power generation properties and stability of a three-layered co-sintered film of flat plate type. Mitsui Shipbuilding has reached a near final conclusion on the basic structure of gas separator cells. The Central Electric Power Research Institute has completed a conceptual design on a 300-MW class composite power generation system in which SOFC and gas turbines are combined. The Electric Power Development Company has discussed problems in SOFC composite power generation development using coal gasified fuel. (NEDO)

  14. Fundamental analysis of thermally regenerative fuel cell utilizing solar heat; Taiyonetsu wo riyosuru netsu saiseigata nenryo denchi no kiso tokusei no kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Ando, Y.; Tanaka, T.; Takashima, T.; Doi, T. [Electrotechnical Laboratory, Tsukuba (Japan); Aosawa, T.; Kogoshi, S. [Science University of Tokyo, Tokyo (Japan)

    1997-11-25

    Study was made on a thermally regenerative fuel cell using solar heat. The thermally regenerative fuel cell was devised which is composed of 2-propanol liquid-phase endothermic dehydrogenation at nearly 100degC, and acetone liquid- phase exothermic hydrogenation at nearly 30degC as reverse reaction. This low-temperature dehydrogenation can relatively easily utilize a flat solar heat concentrator. 2-propanol dehydrogenation generates acetone and hydrogen. Generated acetone generates electric power in hydrogenation, generating propanol. This propanol regenerates acetone and hydrogen in dehydrogenation. The activity of Ru and Pt composite catalyst was considerably higher than that of Ru or Pt single catalyst. The activity was also higher in carbon felt or carbon cloth carrier than carbon plate carrier. The open circuit voltage of the fuel cell was estimated to be 110-120mV, nearly consisting with theoretical values. Short circuit current was also estimated to be 9-11mA, suggesting reduction of its internal resistance as an important subject. 4 refs., 5 figs., 2 tabs.

  15. Research and development of molten carbonate fuel cell power generation systems. ; Supporting studies. Yoyu tansan'engata nenryo denchi hatsuden system no kenkyu kaihatsu. ; Support kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This paper reports supporting studies including material technology development for molten carbonate fuel cell power generation systems. Discussions have been given on metallic materials for cathodes and anodes, separator materials, and separator material plating technologies. Ribbed anodes have been discussed. Investigations have been made on ceramics as to adjustment of electrolyte plate materials as an integrating technology, sheet forming conditions, and degreasing behavior in the integrated products. Cathode material development and ceramic material property evaluation have been made. Paper electrolyte plates have been developed, from which electrolyte plate matrices have been obtained that are more difficult to break, and exhibit good cell characteristics. For coal gas handling technology development, discussions have been made on a dry refining technology and an inorganic salt type gas refining technology. In order to develop a capacity increasing technology, a simulation method has been discussed by assuming a model plant. The Texaco oxygen blowing process has been discussed as a coal gasification system, and the dry system as a gas refining system. The PSA system and the inorganic salt system have been discussed to develop a high-performance gas separating and refining technology. 8 tabs.

  16. FY 1999 Report on the technical results. Part 2-1. Development of fuel cell power generation technologies (Research and development of molten carbonate fuel cell power generation system); 1999 nendo nenryo denchi hatsuden gijutsu kaihatsu seika hokokusho. 2-1. Yoyu tansan'engata nenryo denchi (hatsuden system no kenkyu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-01

    This research and development project is aimed at modification and improvement of the stacking technologies, to improve service life and performance of the molten carbonate fuel cell power generation system and reduce its cost. For the cross-flow type stack, optimization of the anode firing conditions leads to controlled reduction of the fine pores, and incorporation of the cathode with MgO successfully leads to controlled elution of NiO and Ni short-cut. For the separator, the service life is extended by treatment of the material with Al and controlling its rigidity. The cell life prediction method is improved to enhance its accuracy. The cell life of -4.3mV/1,000h is achieved by these technologies. For the parallel-flow type stack, the electrodes are improved to achieve the cell life of -1.4mV/1,000h, the technologies for producing the separator for a 1m{sup 2} class unit are developed, and the basic structures of a large-capacity stack are designed. For the internal reforming type, a 200kW class reforming stack is constructed, and operated for 5,259 hours. The causes for electrolyte loss are analyzed by developing the relationships between operating temperature and electrolyte loss, electrolyte mass and sustainability of the cell characteristics, and steam partial pressure over the cathode and electrolyte loss, and also by testing the Ni short-cut. (NEDO)

  17. Report on achievement in developing fuel cell power generation technology in fiscal 1998. Research and development of molten carbonate fuel cell power generation system (Test of the research result report); 1998 nendo nenryo denchi hatsuden gijutsu kaihatsu seika hokokusho. Yoyu tansan'engata nenryo denchi hatsuden system no kenkyu kaihatsu (kenkyu seika no honbun)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    This paper summarizes the text of the research result report in the separate volume II-1 from among the fiscal 1998 report on the achievement made on researching and developing a molten carbonate fuel cell (MCFC) power generation system. For the AC-DC type system whose high performance and large capacity stacks are being developed, detail designs were made on 250-kW class stack module assembly and installation procedure. At the same time, processing and forming were continued on such main components as electrodes, electrolyte plates and separators. The cells were assembled as modules, sintered, installed and adjusted. Aids were given by the process and control (PAC) test on devices and piping of the fuel cell system block. Cell life extension is also under study. For the parallel flow type stack, two 250-kW stacks were fabricated, and an overall adjustment test was begun thereon in March. For the reformer, an internal reforming system was developed for the 200-kW class system, whose adjustment test is scheduled for April 1999. Capacity increase is also under discussion. For practical use of MCFC, stack life of 40,000 hours is said required. The current status is at the level of exceeding 10,000 hours, but the necessity is seen in suppressing voltage drop associated with lapse of time. (NEDO)

  18. Research and development of a phosphoric acid fuel cell power generation system. ; Research and development of a fuel cell power generation system used in an isolated island. Rinsangata nenryo denchi no sogoteki gijutsu kaihatsu. ; Ritoyo nenryo denchi hatsuden system no kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This paper reports the research and development work on a fuel cell system using phosphoric acid fuel cells to be used in an isolated island. The system researches have included discussions on a technology to link alternating current with a diesel engine generator, a technology for optimal operation with a diesel engine generator, measures against salt damage to the present system, and a methanol acquiring method. The elementary researches have conducted development of composite electrodes, a composite electrode cell technology, and a methanol reforming technology with high load followability. The trial fabrication and operational researches of the power plant have performed plant design, trial fabrication of the fuel cells and reforming devices, and investigative studies on promoting introduction of the present system. In the system researches, an inverter has been designed to suppress overall voltage harmonic distortion the inverter generates to below 2% to 3%. The element researches have realized mass production of 3600-cm[sup 2] class composite electrode substrates. A small methanol reformer experiment has been carried out to verify the reformer's load responsiveness. A life evaluation on the catalyst combusting catalyst has discovered no deterioration in the catalyst in a 1000-hour continuous operation. 8 figs., 4 tabs.

  19. Achievement report for fiscal 1998 on development of power generation using fuel cells. Research and development of molten carbonate fuel cell (II-2, text of the achievement); 1998 nendo nenryo denchi hatsuden gijutsu kaihatsu seika hokokusho. Yoyu tansan'engata nenryo denchi hatsuden system no kenkyu kaihatsu (II-2, kenkyu seika no honbun)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    The effort aims at developing a 1000kW-class power plant and also at using gasified coal as fuel in the future. The fuel system facilities include a high-temperature blower. The exhaust heat recovery facilities comprise a heat recovery steam generator (HRSG) and a turbine compressor. As for the electrical system facilities, an inverter is installed, tested, and adjusted. Control system facilities are also tested and adjusted. In relation with the operation of the plant, coordination is conducted about technological and process-related matters with the Kawagoe thermal power station of Chubu Electric Power Co., Inc., where the fuel cell power plant is to be constructed, which is for the smooth execution of a test run. Ceramic-based cathode materials are being developed, which is for the fabrication of stacks improved in performance, higher in current density, longer in life, and lower in cost. Also exerted are efforts at developing multiple-function electrolyte plates and metallic materials (for example for separator plating). The extent of the acceptability of impurities concentration and gas refining systems are also under study, which is to prepare for future coal gasification. Reference is also made to the study of a total system. (NEDO)

  20. Fiscal 1998 research report. Survey on data collection for development of new energy technology (fuel cell); 1998 nendo chosa hokokusho. Shin energy gijutsu kaihatsu kankei data shu sakusei chosa (nenryo denchi)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    This report is composed of Part 1: the development trend of fuel cells in fiscal 1998, and Part 2: the collected data and appendices. Part 1 includes 4 chapters, (1) The outline of the development trend, (2) Stationary fuel cell, (3) The development trend of fuel cell vehicles, and (4) The development trend of small transportable fuel cells. The report newly includes the development trend of small-capacity fuel cells and the report on 1998 Fuel Cell Seminar notable as an international conference on fuel cell summarizing the trend of fuel cells in fiscal 1998, as compared with the fiscal 1997 report. Part 2 is the collected data on domestic and foreign demonstration operation results of fuel cells, and technical development of every fuel cell. In addition to various collected data on the whole of fuel cells and their use techniques, Part 2 includes the principle, features, system configuration, performance simulation technique, application and market analysis of fuel cells, and the national policy and concerned laws on a subsidy system for introduction of fuel cells, for example. (NEDO)

  1. Fiscal 1996 result reports of the researches under consignment from NEDO. Developments of fuel cell technology, polymer electrolyte fuel cell, fuel cell power generation system technology, and high-voltage type several tens kW class distributed power source system; Shin energy sangyo gijutsu sogo kaihatsu kiko itaku gyomu 1996 nendo seika hokokusho. Nenryo denchi gijutsu kaihatsu, kotai kobunshigata nenryo denchi no kenkyu kaihatsu, hatsuden system gijutsu kaihatsu, koden`atsugata suju kW kyu bunsan dengen system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This paper precisely reports the research result on development of fuel cell technology in fiscal 1996. On verification of cell durability, the cell test result in hydrogen including CO of 100ppm using Pt-Ru catalyst as CO resistant catalyst showed that the loss percent of cell voltage decreases with an increase in Ru content. On development of stack technology, the carbon humidification plate superior in chemical stability was developed as one of the parts for layered stacks. The separator with a water- permeable carbon plate and serpentine flow fields was fabricated for highly layered stacks, and achieved the target performance in single cell power generation test. On establishment of design basis for compact fuel processor, the bench-scale test was conducted of Ru/{gamma}-Al2O3 and Pt-Ru/{gamma}-Al2O3 catalysts as advanced CO selective oxidation catalyst for CO reducers. On demonstration test for the several tens kW class stationary power plant, the system configuration of power generation plants using natural gas as fuel was studied. 106 figs., 38 tabs.

  2. Research and development of molten carbonate fuel cell power generation systems. ; Development of stacks and peripheral systems. Yoyu tansan'engata nenryo denchi hatsuden system no kenkyu kaihatsu. ; Sutakku oyobi shuhen system no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This paper reports research and development of molten carbonate fuel cell power generation systems of composite large-capacity type, variation large-capacity type, and internal reforming type. Development works on the composite large-capacity type stacks included trial fabrication of basic modules and composite large-capacity cells, development of high-performance long-life electrodes, electrolyte plates, and high corrosion resistant cell constitutive materials, heat resistant cycling tests and life tests, and development of a technology to use higher pressures in fuel cells, and a technology to cool and seal laminar cells. Development works on the variation large-capacity stacks have performed studies on electrode life extension, pressurized operation technologies, tightening methods, fabrication of thin plate processed separators, electrodes, and electrolyte plates, power generation tests on large-area cells, and cooling characteristics analysis. In order to establish an internal reforming fuel cell technology, elucidation has been given on deactivation mechanisms in internal reforming catalysts, as well as discussions on structures of internal reforming fuel cells. As stack operational researches, evaluation tests have been given on 10-kW and 100-kW class stacks. Discussions have been given on heat exchange type and two-step catalyst combustion type reformers as peripheral devices. 26 figs., 6 tabs.

  3. FY 1994 report on the results of the R and D of solid oxide fuel cells (SOFC); 1994 nendo SOFC kotai denkaishitsugata nenryo denchi no kenkyu kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    Development of fuel cell power generation technology and R and D of solid oxide fuel cells were carried out, and reports of the FY 1994 results of companies were summed up. As to the R and D of the cell module, R and D were conducted of 'large area cell' by Fuji Electric Corporate R and D, Ltd. and 'combined cell module' by Sanyo Electric Co. As to the R and D of materials/basic technology, the following were conducted: 'R and D of the electrode micro structure' by Japan Fine Ceramics Center, 'R and D of the electrode structure by thermal spraying method by Fujikura Ltd., 'R and D of the multi-functional fuel electrode' by Mitsubishi Heavy Industries, Ltd., 'R and D of the cofiring technology' by Murata Mfg. Co., and 'R and D of the current collecting technology' by Mitsui Engineering and Shipbuilding Co. Concerning the R and D of the system, 'the system study' by Central Research Institute of Electric Power Industry' and 'development of element technology for periphery devices' by The Japan Research and Development Center for Metals. (NEDO)

  4. Research and development of molten carbonate fuel cell power generation systems. ; Researches on a total system. Yoyu tansan'engata nenryo denchi hatsuden system no kenkyu kaihatsu. ; Total system no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    This paper reports conceptional designs for practical units for a molten carbonate fuel cell power generation system and coal gasification technologies. Before advancing the conceptional designs for practical units to be used in electric utility businesses, investigations have been given on literatures on about 60 cases of molten carbonate fuel cell power generation systems that had been published inside and outside Japan so far. Discussions have been given on profiles of these plants as seen from the design results. This paper summarizes the target specifications to the plants, which may be used as basics for conceptional designs of megawatt class plants. The target specifications cover operating conditions, fuel conditions, environmental conditions, and economies. Investigations made for coal gasification technologies include those on literatures such as the 'U.S. Coolwater Project' and the 'pressurized two-step jet bed gasification furnace developed by the Electric Utility Research Center', as well as the '200 t/d jet bed coal gasification furnace' to be developed by NEDO and a dry gas refining plant. Target specifications for MCFC power generation plants have been established by dividing the plants into 0.5 to 1 million kW class, 200 to 500 thousand kW class, and 10 to 50 thousand kW class. 1 tab.

  5. Fiscal 1997 report on the results of the international standardization R and D. R and D of the standardization of a method to test acceleration life of phosphorous acid fuel cells; 1997 nendo seika hokokusho kokusai hyojun soseigata kenkyu kaihatsu. Rinsangata nenryo denchi no kasoku jumyo shiken hoho no hyojunka ni kansuru kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    As for fuel cells, which are expected as a new clean energy, the R and D are being proceeded with in various fields of the world, but the standardization has not been made both in Japan and abroad. In Japan, the situation is that the information on technical terms, indication method, performance test method, and environment/safety test methods of the phosphorous acid fuel cell power generation is publicly spread. In relation to the international promotion of fuel cells to be predicted, it is necessary to internationally standardize cells themselves which are a key component of fuel cell power generation facilities. Phosphorous acid fuel cells are expected of the earliest commercialization of all, but the common test method to evaluate life characteristics of the cell stack has not been established yet. In the R and D, for the purpose of internationally standardizing test methods to evaluate life characteristics of the cell stack, a study on the acceleration life test method of phosphoric acid fuel cells was conducted in terms of the technical trend, data, standard, etc. A plan was prepared on general rules of the method to test acceleration life at the cell reaction part of the small cell, and activities also were started for setting up a technical committee for the fuel cell power system in President`s Advisory Committee on Future Technology. 29 figs., 20 tabs.

  6. 1998 Annual Study Report. Research and development of solid polymer type fuel cells (Development of techniques for power generation systems and several tens kW class, distributed power source systems); 1998 nendo seika hokokusho. Kotai kobunshigata nenryo denchi no kenkyu kaihatsu (hatsuden system gijutsu no kaihatsu / koden'atsugata su 10kW kyu bunsan dengen system no kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    The cells are tested using a CO-containing synthetic reforming gas in 1998, to verify the long-term characteristics of the solid polymer type fuel cells. The cells, equipped with the anode catalyst developed therefor, are tested for extended periods, to confirm the performance and stability in the synthetic gas flow. For development of the catalyst, the optimum content of Ru in the Pt and Ru alloy composition is determined. For the cell tests, the single- and 3-cell units are tested for extended periods. For verification of commercial viability of the stacked cell systems, the cell-humidifying techniques are developed, which can uniformly humidify each cell in the stacked unit with a number of cells, after investigating the effects of temporal changes in water permeability, pretreatment conditions and film thickness. These techniques are used to develop and operate a 10kW, stacked cell unit, which successfully generates power of 10.6 kW at the rated current density, exceeding the target of 10 kW. For development of design bases for compact fuel treatment system, the techniques which allow reduction of CO concentration to 10 ppm or less at high repeatability are developed. (NEDO)

  7. Achievement report (edition B) for fiscal 1999 on development of technology to manufacture coal gas for fuel cells. Studies by using pilot test facilities (Volumes for equipment fabrication and constructions, and trial run design); 1999 nendo seika hokokusho (B ban). Nenryo denchi you sekitan gas seizo gijutsu kaihatsu - Pilot setsubi ni yoru kenkyu (kisokoji kiki seisaku hen shiunten sekkei hen)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    With an objective to develop a coal gas manufacturing system for fuel cells, research and development has been performed on a oxygen-blown coal gasifier and researches on a technology to purify gases for fuel cells. This paper summarizes the achievements in fiscal 1999. The current fiscal year has performed, among other the pilot plant construction works, execution of the above-the-ground constructions for the operation center and compressor room building, construction of the cooling water tanks, and partial improvement of roads in the plant site. In the gasifier facilities, items of equipment were fabricated, some of the outsourced articles were procured, and the installations thereof were carried out. For the gas purifying equipment, installation of the gas analyzer room was executed. In the trial run design, discussions were given on the systematic improvements in the test items, the gas sampling procedures, the unit protecting interlock, and the facility protecting logic. For the trial run design, establishment has been implemented on the efficient and functional test plans by establishing priority on the tests to be executed, so that the development items demanded in the pilot test and research can be achieved within the limited test processes. (NEDO)

  8. Fiscal 1993 international research cooperation project. Feasibility study of finding out the seeds of international joint research (technology for environmental preservation using biotechnology, technology for effective use unused hydrocarbon resource, technology of solid electrolyte fuel cells for high-efficient electric vehicles); 1993 nendo kokusai kenkyu kyoryoku jigyo. Kokusai kyodo kenkyu seeds hakkutsu no tame no FS chosa (biotechnology ni yoru kankyo taisaku gijutsu, miriyo tanka suiso shigen no yuko riyo gijutsu, kokoritsu denki jidosha no kotai denkaishitsu nenryo denchi gijutsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    This project is aimed at internationally cooperating in the R and D of industrial technology and improving industrial technology of Japan. For it, the following three technologies were investigated: 1) environmental preservation technology using biotechnology, 2) technology for effective use of unused hydrocarbon resource, 3) solid electrolyte fuel cell (SOFC) technology for high-efficient electric vehicles. In 1), bio-remediation is a choice as the result of trially using technologies for remediation of the environment polluted by pollutant, but it is not a technically completed one, but one which will be improved by trial and error. By the application of gene engineering, the use of gene recombination enables wide spread of decomposition genes. In 2), technical subjects were studied such as superheavy distillate, oil shale, coalhead methane and methane hydrate. In 3), designed were cylinder type and planar type SOFC of 850degC operation and 10kW output. Accumulation and weight of a total SOFC system are 81 liters and 100 kg in cylinder type and 136 liters and 200 kg in planar type. The vehicle can be equipped with the SOFC. 171 refs., 72 figs., 54 tabs.

  9. Cell with scrolled electrodes. Uzumaki jo denkyokutai wo sonaeta denchi

    Energy Technology Data Exchange (ETDEWEB)

    Kamibayashi, M.; Morioka, Y. (Sanyo Electric Co. Ltd., Osaka (Japan))

    1990-10-03

    Non-sintered electrode plates produced by direct filling of paste state active materials in metal fiber felt type porous body are proposed recently for use as electrode plates for alkali cells and the like. Although this type of electrode plates can be produced with a simple facility because sintering process is not required, it has a shorcoming of internal short circuiting because metal fibers pass through the separator due to fuzzing of metal fiber. According to this invention, a sheet comprising metallic fibers oriented at right angles against the scrolled direction of the electrode plate is stacked on the surface of the metal fiber felt type porous body sheet when it is scrolled with the interposed separator. As the result, fibers are not bent and does not protrude from the surface of sheet to pass through the separator because each metallic fiber comprising the metallic sheet on the surface are arranged at a right angle against the direction of scrolling of the porous sheet. 2 figs., 1 tab.

  10. Simulation of PV/FC power hybrid system. Change of system capacity with load form factor; Taiyoko hatsuden nenryo denchi hybrid system no simulation. Fuka keijoritsu ni yoru system yoryo no henka

    Energy Technology Data Exchange (ETDEWEB)

    Sekiguchi, N.; Tani, T. [Science University of Tokyo, Tokyo (Japan)

    1997-11-25

    Study is conducted of a photovoltaic/fuel-cell hybrid system whose power storage is a hydrogen storage that uses a hydrogen absorbing alloy. In a simulation in this research, the solar cell conversion efficiency is changed from 15.0% to 21.0% and the fuel cell power conversion efficiency from 40.0% to 50.0%, and the resultant changes in the capacity and operation rate are investigated for each of the devices in the system. The findings follow. A 1.0% change in the solar cell conversion efficiency results in a 4.8kW change in the solar cell capacity and a 1.6-ton change in the hydrogen storage capacity. With a 1.0% change in the fuel cell power conversion efficiency, there is a 14.7kW change in the solar cell capacity and a 5.3-ton change in the hydrogen storage capacity. The fuel cell capacity is not dependent on the solar cell conversion efficiency or fuel cell power conversion efficiency but on the maximum load in each of the load form factors. The rate of occurrence of an operation rate of less than 30% is 54.7% both in DC/DC converter and hydrogen generator, 24.6% in fuel cells, and 16.7% in the DC/DC inverter. 7 refs., 7 figs., 1 tab.

  11. Production method of thin film solar cell; Hakumaku taiyo denchi no seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Oki, K.; Watanabe, T.; Matsui, M.

    1996-01-23

    This invention relates to the film formation of chalcopyrite type compound semiconductor used for thin film solar cell. In the case of CuInS2 thin film, heteromorphic phases such as CuIn5S8, Cu2S, and In2S3 are formed on the top surface together with the CuInS2 phase, resulting in the decrease in junction property when n-type semiconductor layer such as CdS layer is formed on it. According to the invention, p-type semiconductor layer made of chalcopyrite type compound semiconductor is dipped into an ammonia water before being laminated with n-type semiconductor layer. Although higher concentration and higher temperature of the ammonia water accelerates the heteromorphic phase film removal velocity, it also gives rise to higher evaporation rate of ammonia. The preferable concentration and temperature are, therefore, 0.01 - 50% and 5 - 80{degree}C, respectively. In this way, the chalcopyrite type compound semiconductor thin film free from heteromorphic phases on its surface can be produced. The thin film solar cell produced by using such thin film has a high conversion efficiency because of a good junction property with n-type semiconductor. 1 fig.

  12. Thin film solar cell and its production method; Hakumaku taiyo denchi oyobi sono seiho

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, H.; Yamamoto, K.; Mishima, T.; Matsuda, T. [Daido Hokusan Co. Ltd., Osaka (Japan). Sakai Lab.

    1997-01-17

    An attempt has been made to replace the single crystal silicon substrate for other inexpensive substrate coated with Si thin film for cost saving in the silicon solar cell production. It was found, however, a big difference in thermal expansion coefficient between the substrate and Si brought about a big warp of the substrate when the Si film was made thick enough for solar cell use. This invention solves the problem. The Si thin film is grown through a mask having many holes with constant interval instead of being grown as a continuous layer. The Si film is, therefore, formed in island structure which rises from many holes. The island structure crystals exist, being separated from each other. They consist of discontinuous points. So that they can expand thermally in accordance with the thermal expansion of the substrate. Even if there is a difference in thermal expansion between the inexpensive substrate and Si crystal film, little warp takes place in the laminate. 8 figs.

  13. Development of coal gas production technology acceptable for fuel cells; Nenryo denchiyo sekitan gas seizo gijutsu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, T. [Center for Coal Utilization, Japan, Tokyo (Japan); Kimura, N.; Omata, K. [Electric Power Development Co. Ltd., Tokyo (Japan)

    1996-09-01

    In utilizing coal for high-efficiency direct power generation using fuel cells, it is necessary that coal be fed into the fuel cells after having been made into ash-free gaseous fuel. Research and development works are being carried out with an objective to develop a coal gasification furnace most suitable for fuel cells and establish a system to refine coal up to the one that can be fed into fuel cells. Fiscal 1995 has conducted investigations on coal gasification technologies, air separation technologies, and gas refining technologies as the important element technologies, and a trial design on integrated coal gasification fuel cell (IGFC) systems. This paper reports from among the above items the result of the trial design on an IGFC system using molten carbonate fuel cells. The paper describes system comparison on paths of produced gases and anode waste gas, comparison on refining processes using a wet system and a dry system, and parameter studies on oxygen concentration in gasifying agents. It was made clear that the suitable furnace is an oxygen blown coal gasification furnace, and the power generation efficiency at the system terminal can be higher than 53%. 11 figs., 6 tabs.

  14. Technological development for super-high efficiency solar cells. Technological development for super-high efficiency singlecrystalline silicon solar cells (super-high efficiency singlecrystalline Si solar cells); Chokokoritsu taiyo denchi no gijutsu kaihatsu. Chokokoritsu tankessho silicon taiyo denchi no gijutsu kaihatsu (chokokoritsu tankessho silicon taiyo denchi cell no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on technological development of super-high efficiency singlecrystalline silicon solar cells in fiscal 1994. (1) On development of high-performance light receiving layer, the fine electrode for receiving surfaces was designed to reduce serial resistance, and the high-quality oxide passivation film was studied to reduce surface recombination velocity. (2) On development of forming technology of back heterojunction, the high-quality cell with B-doped fine crystalline Si film on its back was studied by heat treatment of the fine crystalline Si film, and the cell structure with high back reflectance of light was also studied. (3) On analysis for high-efficiency cells, the relation between the back recombination velocity at the interface between p-type substrate and back passivation film, and the internal collection efficiency as probe light was injected from the back, was calculated by numerical simulation. As a result, the cell back recombination velocity could be evaluated by measuring the spectral internal collection efficiency to back injection. 15 figs., 6 tabs.

  15. Roof-mounted solar cell and method of mounting. Yane secchi gata taiyo denchi oyobi sono secchi hoho

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, M.; Minami, K.; Yamaki, T. (Sanyo Electric Co. Ltd., Osaka (Japan))

    1991-09-02

    This invention provides a roof-mounted solar cell which can be readily installed on the existing roofs without impairing the roofs and excels in durability. In this invention, a solar cell panal is made by placing at least one solar cell module into a frame and this panel is mounted on a roof via a spacer in a freely movable arrangement. The frame and the material under the eaves are fixed by means of a wire. In addition, a roughly L-shaped clamp made of a shape memory alloy is fixed to the material under the eaves. This clamp and the frame of the solar cell panel can be fixed by means of a wire. At installation, a frame to assemble the solar cell module is mounted by means of a spacer in freely movable arrangement. After this frame is ficed to the part under the eave, the solar cell module is fixed into the frame body. Durability is improved because the vibration (e.g., of earthquakes) is mutually released through the frame, wires and the roofs, thus enhancing its durability. 12 figs., 1 tab.

  16. On practicality of a hybrid car with solar cells; Taiyo denchi wo tosaishita hybrid car no jitsuyosei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, K.; Nagayoshi, H.; Kamisako, K. [Tokyo University of Agriculture and Technology, Tokyo (Japan)

    1997-11-25

    The paper stated a development of a hybrid car which is a parallel type with gasoline engine and electric motor as driving source (connecting each according to the situation) and is also equipped with solar cells. Specifications are gasoline engine of 1200cc, induction motor of 5.5kW, lead battery of 288V and 7.2kWh, monocrystal silicon solar cells of 180W maximum output, and body weight of 1100kg. The rear wheel is driven by electric motor, and the front wheel by gasoline engine. The car is loaded with battery charge use solar cells on hood and roof. To enhance cleaning degree, 1.6kW solar cells are installed as an installed power system and used for battery charge. Even by an electric motor with output less than that of the usual electric car, harmful exhaust gas emitted in start-up can be controlled. This is because the electric motor can be used in accelerating. It was confirmed that the power required for it could be supplied by solar cells installed on the car. The hybrid car is practically useful for prevention of local air pollution. 5 refs., 4 figs., 2 tabs.

  17. Stabilized efficiency of stacked a-Si solar cell; Sekisogata a-Si taiyo denchi no anteika koritsu

    Energy Technology Data Exchange (ETDEWEB)

    Takahisa, K.; Kojima, T.; Nakamura, K.; Koyanagi, T.; Yanagisawa, T. [Electrotechnical Laboratory, Tsukuba (Japan)

    1997-11-25

    Different types of tests combining light and temperature were carried out in a laboratory on predicting long-term performance of stacked amorphous silicon solar cells. Cell terminals were left open, xenon was used as an irradiation light source, and cell temperature was controlled within {+-} 2 degC of the setting. The result of the experiment may be summarized as follows: with regard to the deterioration characteristics, the speed in which the efficiency changes reached a maximum within 10 hours, and thereafter the change has slowed down gradually in the case of temperature at 50 degC; in the case of 25 degC, the maximization is reached between 500 and 1000 hours; the stabilization efficiency turns out to be a pessimistic value according to the saturated value derived from an experimental expression, hence the value would have to be expressed by specifying cell temperatures, light intensities and elapsed time; the minimum value of seasonal variation may be estimated at about 85% as a pessimistic value; for recovery characteristics, the saturated value for the recovery tends to become lower as the lower the value immediately before the recovery; and if the light intensity is varied, the deterioration characteristic shifts to that at an individual light intensity. 4 refs., 11 figs., 2 tabs.

  18. Resin composite for sealing and its use in a solar cell. Fushiyo jushi soseibutsu oyobi sore wo mochiita taiyo denchi

    Energy Technology Data Exchange (ETDEWEB)

    Toma, H.; Mimura, T.; Takehara, N.

    1994-01-28

    This invention presents resin composites for sealing of a solar cell composed of a hardening resin and a thermoplastic resin which has a number average molecular weight larger than that of the hardening resin and is soluble in the hardening resin, and the invention affords a solar cell to endure a long-term stable operation and to give a good performance. The hardening resin includes unsaturated polyester resin, phenolic resin, alkyd resin, unsaturated acrylic resin, epoxy resin, polyurethane resin, melamine resin, diallyl phthalate resin, their oligomers and their modifications. The thermoplastic resin includes saturated polyester resin, phenolic resin, acrylic resin, styrene resin, epoxy resin, polyurethane resin, polyvinyl acetate resin, polyvinyl chloride resin, polyvinyl alcohol resin, polyacetal resin, their modifications and their copolymer resin. 2 figs., 3 tabs.

  19. Estimation of the charge quantity from solar cell to battery; Taiyo denchi ni yoru chikudenchi eno juden yosoku

    Energy Technology Data Exchange (ETDEWEB)

    Tsutsumi, K.; Nishitani, M. [Daiichi University, College of Technology, Kagoshima (Japan)

    1996-10-27

    In performing an experiment of running a small electric vehicle by installing solar cells in it and by charging the storage battery at a specific voltage, an estimation was made on the charge quantity to the battery for each solar altitude and inclination of a module at different hours. The solar altitude was determined at Daiichi University, College of Technology, according to the month and the time of day from a formula using day-declination and time equation of a chronological table of science. The quantity of global solar radiation was determined by resolving the solar radiation into its direct and diffuse components on the basis of the extra-terrestrial solar radiation quantity with the change in radius vector taken into consideration; and then, the global solar radiation on the inclined face was obtained from the angle of inclination and incidence. On the roof of a Daiichi University building, solar cell modules were installed facing north and south at 0{degree}, 30{degree}, 45{degree}, 60{degree} and 90{degree} each, so that a short-circuit current was measured for each differently inclined angle. As a result of the experiment, shown in an regression formula is a relation between the temperature conversion value of the maximum output of the solar cell at the standard temperature of 25{degree}C and the quantity of solar radiation on the inclined surface. Consequently, it enabled the prediction of a charging quantity, in the case of running a small vehicle with solar cells installed, from the quantity of solar radiation on the inclined surface in the clear weather. 2 refs., 4 figs., 2 tabs.

  20. Technological development for super-high efficiency solar cells. Technological development for crystalline compound solar cells (high-efficiency III-V tandem solar cells); Chokokoritsu taiyo denchi no gijutsu kaihatsu. Kessho kagobutsu taiyo denchi no gijutsu kaihatsu (III-V zoku kagobutsu handotai taiyo denchi no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on technological development of III-V compound semiconductor solar cells in fiscal 1994. (1) On development of epitaxial growth technology of lattice mismatching systems, the optimum structure of InGaAs strain intermediate layers was studied for reducing a dislocation density by lattice mismatching of GaAs layer grown on Si substrate and difference in thermal expansion coefficient. The effect of strain layer on dislocation reduction was found only at 250dyne/cm in strain energy. Growth of GaAs layers on the Si substrate treated by hydrofluoric acid at low temperature was attempted by MBE method. As a dislocation distribution was controlled by laying different atoms at hetero-interface, the dislocation density of growing layer surfaces decreased by concentration of dislocation at hetero-interface. (2) On development of high-efficiency tandem cell structure, tunnel junction characteristics, cell formation process and optimum design method of lattice matching tandem cells were studied, while thin film cell formation was basically studied for lattice mismatching tandem cells. 45 figs., 8 tabs.

  1. Concentration characteristics and cell arrangement in luminescent concentrator PV modules; Keiko shukogata taiyo denchi module no cell haichi to shuko tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Inamura, A. [Science University of Tokyo, Tokyo (Japan); Sakuta, K. [Electrotechnical Laboratory, Tsukuba (Japan)

    1997-11-25

    A luminescent concentrator PV module requires no tracking equipment and can use scattered light. A mini PV module was prepared from a luminescent plate of 100times100times3mm, and a single-crystalline PV cell of 100times20mm. Characteristics of various prototype modules with different PV cell areas and cell arrangements were also measured. Four kinds of edge reflecting materials with different reflectances by various white coating were applied to Al sashes for module frames, and each sash was fixed on one edge of the luminescent plate. In experiment, 3 other edges were covered with black tapes to reduce each reflectance to 0%. Although PV module output was affected by reflectance of edges, the output was satisfactory at 90% or more in reflectance showing no difference in output. A concentrating efficiency decreased with an increase in luminescent plate (concentrator) area, while it was improved by cell arrangement with short optical pass length, and cell arrangement hardly affected by edge reflection. 4 refs., 7 figs.

  2. Technological development for super-high efficiency solar cells. Survey on the commercialization on analysis; Chokokoritsu taiyo denchi no gijutsu kaihatsu. Jitsuyoka kaiseki ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the survey results on analysis of super-high efficiency solar cells for practical use in fiscal 1994. (1) On the survey on crystalline compound solar cells, it was pointed out that the present study target is III-V compound semiconductor solar cell, and efficiencies of 36-39% are theoretically expected by use of two-junction cells. (2) On structure of super-high efficiency solar cells of 40%, selection of upper and lower cell materials for multi-junction cells, high-efficiency tandem Si solar cells, and the merit and possibility of light collection operation were surveyed, and their issues were discussed. (3) On physical properties of mixed crystalline semiconductors and characteristic evaluation of solar cells, impurities, trap center, minority carrier life, and applicability of supper lattice structure to high-efficiency solar cells were surveyed. (4) On fabrication technology of compound semiconductor solar cells, various problems of and approaches to electrode formation and antireflection film technologies, the meaning and issues of thin film substrate technology and continuous process, trial calculation of costs, safety, and resource problem were surveyed.

  3. Indirect solar-pumped laser diode using a solar cell; Taiyo denchi wo mochiita taiyoko kansetsu reikigata handotai laser no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kanamori, Y.; Yugami, H.; Naito, H.; Arashi, H. [Tohoku University, Sendai (Japan). Faculty of Engineering

    1996-10-27

    This paper describes the operating characteristics of a stabilizing circuit using commercial electricity, those of a stabilizing circuit using solar cells, relation between the quantity of solar radiation and the maximum output of a semiconductor laser diode (LD), and simulation results of annual LD output in Sendai City. The stabilizing circuit for the solar-cell driven LD was structured such that the output of the solar cell panels was guided to a DC/DC converter, that the voltage was set at a prescribed value and that the current was stabilized with the use of power MOSFET. The solar cells used in the experiment were monocrystal silicone solar cells with the maximum output of 53W each. In the experiment, the LD was protected by stabilizing the current at a set value when an excess current was supplied to the stabilizing circuit. As a result of the simulation of the annual LD output from the meteorological data of Sendai City, it was predicted that a solar cell of approximately 1kW was able to provide an annual output of 102MJ and that the efficiency was highest with four sheets of the solar cell. Consequently, consistency proved to be essential between the LD and the solar cell output. 3 refs., 7 figs.

  4. Prismatic lithium/thionyl chloride cells, EP series''. Kakugata enka thionylter dot lithium denchi EP series''

    Energy Technology Data Exchange (ETDEWEB)

    Kogure, M.; Ide, M.; Mizutani, M. (Japan Storage Battery Co. Ltd., Kyoto (Japan))

    1990-06-25

    This paper reports on a new type lithium-thionyl chloride cell of high safety. Its structure and characteristics are summerized as follows: first, a porous solid of carbon black, that is the positive electrode, including electrolyte solution of SOCl {sub 2} occupies central part of the interio of a prismatic case made of a stainless steel plate, that is the negative electrode, and a thin plate of lithium covers the inner surface of the steel plate, a glass fibre layer being placed in between the lithium plate and the carbon black solid; second, the cell continues to discharge at constant voltage (3.6V) until its life finishes, for instance, for over 10 years when connected to a risistor of 150k {omega}, third, the cell is effectively used at temperatures between {minus} 55 and 85 centigrade; fourth, the cell is preserved for a long duration without scarcely suffering in its efficiency, its capacity decrea-sing at the rate of 0.5 - 1.0% per year; fifth, the cell does not burst, catch fire or explode even if it is short-circuited, swing violently and then fallen from a height of 1.9m to concrete floor, crushed and, in particular, heated in various ways (it is so de-vised that SOCl {sub 2} vapor escapes through the glass seal adjacent to the positive terminal at temperatures about 160 centigrade). 2 refs., 10 figs.

  5. Control method for light deterioration of amorphous solar cell. 2. Temperature effect method; Amorphous taiyo denchi no hikari rekka yokuseiho. 2. Ondo kokaho

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, H.; Itsumi, J.; Sano, N. [Kumamoto Institute of Technology, Kumamoto (Japan)

    1997-11-25

    Experimental studies have been carried out on suppressing early deterioration in amorphous silicon solar cells. The amorphous silicon solar cell is characterized by deterioration due to light irradiation and restoration due to temperature rise. An exposure experiment was performed under three conditions: installation in natural environment, installation with rear side of the solar cells covered with an insulating material, and installation with rear side of the solar cells covered with warming elements and an insulating material. Tests were made on suppressing progress of the early deterioration caused by temperature conditions. As a result, the efficiency in the natural condition was found to decrease as largely as 32% in an open circuit condition and 58% in a short circuit condition. The efficiency reduction rate was smaller in the open circuit condition when the insulation material was installed, but in the short circuit condition, resistance characteristics caused by rain water and electrolytic corrosion were exhibited. For the case with warming elements installed, the reduction in the efficiency was more remarkable, contrary to the expectation. The cause was determined that water existing between the rear side and the warming elements was warmed up, accelerating the electrolytic action, and resulting in deterioration advanced over a wide area in the rear side. 6 refs., 6 figs., 3 tabs.

  6. Development of measurement device for evaluation of solar cell module output. 2; Taiyo denchi module shutsuryoku hyokayo sokuteiki no kaihatsu. 2

    Energy Technology Data Exchange (ETDEWEB)

    Minoda, M.; Itsumi, J. [Kumamoto Institute of Technology, Kumamoto (Japan)

    1996-10-27

    Enhancement in design efficiency may be attained as well as utilization in maintenance if on-the-spot data is made available, for the purpose of flexibly dealing with changes in design or matching with a house structure, in calculating the power generation output of a solar cell (PV) module. Under the circumstances, a small-sized compound measuring device was produced as a prototype which, using an I-V curve tracer, measured output and condition of a roof at the time of installation, compared with the optimum operation and predicted the power generation. The device was structured with the main body consisting of a computing part, measurement controller and power supply and with various sensor modules. The electron load control method was employed in order to measure I-V characteristics of the PV module, since it was desirable to use a variable load and to cover the range from the release voltage of a solar cell to the short-circuit state through the maximum output point. The reference module method was used for the system evaluation. The device was presumably applicable to a PV system design by incorporating a sensor module for measuring design environment data, which was essential at the time of a system design, in addition to those for measuring output. 9 refs., 4 figs., 3 tabs.

  7. Temperature dependence of the early degradation in a-Si solar cells; Amorphous Si taiyo denchi no shoki rekka no ondo izonsei

    Energy Technology Data Exchange (ETDEWEB)

    Takahisa, K.; Kojima, T.; Nakamura, K.; Koyanagi, T.; Yanagisawa, T. [Electrotechnical Laboratory, Tsukuba (Japan)

    1997-11-25

    Discussions were given on early degradation in up to about ten minutes in amorphous silicon solar cells. The experiment has used a model cell of single junction layer for power use with a Glass/ITO/P-i-n:a-Si/Al structure. Test samples were annealed at 130 degC for 30 minutes to eliminate hysteresis of degradation during storage. Xenon was used as an irradiation light source, and the temperatures were varied from 0 to 100 degC and the measurement time was set to 0.1 to 500 minutes. The result of the experiment may be summarized as follows: with regard to time-based degradation pattern for conversion efficiency, the tilt of a pattern to express degradation rate varies with temperature conditions, and changes in 10 to 20 minutes of light irradiation as a boundary; in long-term degradation after 20 minutes, the higher the environmental temperature, the lower the degradation is suppressed, but the rate of initial degradation up to about 10 minutes is higher as the higher the temperature; and the degradation rate increases as the higher the temperature in the initial degradation of about 10 minutes, whereas, corresponding to this fact, it is estimated that a phenomenon is involved, in which carrier recombination defect may increase. 4 refs., 7 figs., 1 tab.

  8. Control method for light deterioration of amorphous solar cell. Temperature effect method; Amorphous taiyo denchi no hikari rekka yokuseiho. Ondo kokaho

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, H.; Yokoyama, S.; Itsumi, J. [Kumamoto Institute of Technology, Kumamoto (Japan)

    1996-10-27

    This paper describes a proposed method for suppressing light deterioration (temperature effect method), in which an annealing effect was always expected by laminating an NEM element and a heat insulation material on the back side of a-Si solar cell module and thereby raising the temperature in the back side of the module, and also describes an outdoor exposure test device completed for the method. The NEM element consisted of conductive potassium titanate and high molecular polymer and was a self temperature-controlling organic exothermic body that required no outside temperature control device. It was provided with a heat generating temperature of 45-75{degree}C as the exothermic property of the element and capable of generating heating temperature arbitrarily according to the purpose. The NEM element varied a resistance value against the ambient temperature and kept the element temperature constant. Measurement was commenced starting April 19, 1996, using the completed outdoor exposure test device and a measuring circuit. The deterioration phenomenon was and from then on continuously examined under the following conditions: (1) measurements were those of clear days only, and (2) measurements to be used were those between 10:00 and 14:00 with the quantity of solar radiation on a constant level. 4 refs., 4 figs., 1 tab.

  9. Technological development for super-high efficiency solar cells. Technological development for crystalline compound solar cells (research and development of composite materials on solar cells under microgravity environment); Chokokoritsu taiyo denchi no gijutsu kaihatsu. Kessho kagobutsu taiyo denchi no gijutsu kaihatsu (bisho juryoku kankyo wo riyoshita taiyo denchiyo zairyo kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on development of composite materials for solar cells under microgravity environment in fiscal 1994. (1) On a thin film capillary method, 26 experiments of GaSb thin film crystal growth were conducted using the especially prepared high-accuracy electric furnace under microgravity. The wettability of thin film crystals was improved by refining equipment. Rhombus crystal planes and large crystal grains were observed in GaSb thin film crystals prepared under microgravity. (2) On a liquid phase method, the effect of the gravity on crystal structure and grain morphology was studied for synthesis of CdS fine grains. (3) On technological development of composite materials, the solidification experiment of Cu-In-Se melt was conducted under short time microgravity of 10{sup -4}g for 10 sec. As a result, more uniform texture and more high crystallinity were obtained under microgravity, and In in melt was concentrated by surface tension effect. It was suggested that high-quality CIS thin films will be obtained by Se doping into Cu-In composite films under microgravity environment.

  10. Research on fabrication technology for thin film solar cells for practical use. Research on low-cost fabrication technology for large-area modules (production technology for amorphous silicon solar cell modules); Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Daimenseki module no tei cost seizo gijutsu (amorphous taiyo denchi module seizo no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on the fabrication technology of amorphous Si solar cell modules in fiscal 1994. (1) On process technology for prototype film substrate solar cells, an advanced preprocessing equipment for film substrates, stepping roll type film forming technology, and prototype submodules were studied. A conversion efficiency of 7.2% was achieved by use of the submodule formed in an effective region of 40 {times} 40cm{sup 2}. (2) On efficiency improvement technology for film substrate solar cells, p/i and n/i interfaces, forming condition for Ag film electrodes, film thickness of transparent electrode ITO, and optimum transmissivity were studied. (3) On technology for advanced solar cells, high-quality a-SiGe: H film, ion control in plasma CVD, and a-Si film formation by plasma CVD using SiH2Cl2 were studied as production technology of narrow gap materials. (4) On advanced two-layer tandem solar cells, the defect density in optical degradation of a-Si cells by reverse bias dark current was evaluated, and outdoor exposure data were analyzed. 4 figs., 1 tab.

  11. Research on fabrication technology for thin film solar cells for practical use. Technological development for qualitative improvement (development of fabrication technology of thin film polycrystalline Si solar cell); Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Kohinshitsuka gijutsu (usumaku takessho silicon kei taiyo denchi seizo no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on the fabrication technology of thin film polycrystalline Si solar cells in fiscal 1994. (1) On the fabrication technology of high-quality Si thin films, the new equipment was studied which allows uniform stable melting recrystallization over a large area. The new equipment adopted a heating method based on RTP system, and is now under adjustment. (2) On the fabrication technology of light/carrier confinement structure, degradation of hydrogen-treated thin film Si solar cells by light irradiation was examined. As a result, since any characteristic degradation was not found even by long time light irradiation, the high quality of the cells was confirmed regardless of hydrogen-treatment. Fabrication of stable reproducible fine texture structure became possible by using fabrication technology of light confinement structure by texture treatment of cell surfaces. (3) On low-cost process technology, design by VEST process, estimation of cell characteristics by simulation, and characteristics of prototype cells were reported. 33 figs., 1 tab.

  12. Research on fabrication technology for thin film solar cells for practical use. Technological development for qualitative improvement (CuInSe2 based PV cell); Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Kohinshitsuka gijutsu (CuInSe2 taiyo denchi seizo no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on the fabrication technology of CuInSe2 based PV cell in fiscal 1994. (1) On formation of high-quality CIGS thin films by bilayer method, Mo film was deposited on a glass substrate by sputtering, and CIGS film with different Ga/In ratios was next formed on the substrate by quaternary simultaneous deposition at different In and Ga deposition speeds. In addition, CdS film was deposited on the CIGS film, and ZnO and ITO films were finally deposited on it by sputtering to complete solar cell. This solar cell offered the maximum conversion efficiency among cells using CIGS film. (2) On formation of high-quality CIGS thin films by three-stage method, a certain correlation was found between substrate temperature and CIGS film composition by monitoring substrate temperature in film forming process. This phenomenon allowed rigorous control of CIS film compositions important for CIS thin film solar cells. (3) On low-cost process technology for thin film formation, Cu(In,Ga)S2 solid solution film was fabricated by expanded selenic process. 3 figs.

  13. Research on fabrication technology for thin film solar cells for practical use. Technological development for qualitative improvement (improvement of conversion efficiency of amorphous silicon solar cells after degradation); Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Kohinshitsuka gijutsu (amorphous taiyo denchi no shoki rekkago koritsu kojo no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on technological development for qualitative improvement of a-Si solar cells after initial degradation in fiscal 1994. On the fabrication technology of light-stable a-Si films, the film formation method possible to control combined hydrogen by repetitive formation/treatment was developed. The obtained high-quality light-stable a-Si film was featured by low defect density in a wide optical band gap range, and defect density of nearly 3 {times} 10{sup 16}/cm{sup -3} after light irradiation. The light degradation rate of the cell where the a-Si film was applied to i layer was relatively stable by 10% or less. The a-Si/a-Si double-layer tandem cell fabricated by this technology produced a high conversion efficiency of 10.5%. By applying {mu}c-Si material to photoactive layer as narrow band gap material, the cell with optical sensitivity even in long wavelength ranges more than 1000nm was obtained. The a-Si/{mu}c-Si double-layer tandem cell produced an initial efficiency of 8.0% and an efficiency after degradation of 7.5%. 12 figs., 3 tabs.

  14. Research on fabrication technology for thin film solar cells for practical use. Research on low-cost fabrication technology for large-area modules (CdS/CdTe solar cell modules); Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Daimenseki module no tei cost seizo gijutsu (CdTe taiyo denchi module seizo no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on the fabrication technology of CdS/CdTe solar cell modules in fiscal 1994. (1) On the fabrication technology for high-efficiency large-area solar cells, high-quality CdTe active layer was studied. S content taken in the active layer at sintering of CdTe decreased with an increase in formed CdTe, resulting in improvement of Voc of cells. (2) On the window layer with wide band gap, the solar cell superior in collection efficiency and photoelectric characteristics could be obtained using the newly developed mixed crystal film of Cd(1-x)Zn(x)S. (3) On the forming technology of large-area coating/sintering films, improvement of CdS film quality was studied by pressurized processing of printed CdS films. As a result, improvement of film density and light transmissivity was confirmed. (4) On the leveling process technology of CdTe films, smooth surface films were obtained by experiment using an equipment simultaneously exciting samples in all directions as one of uniform coating methods of films. 7 figs.

  15. Analysis and evaluation for practical application of photovoltaic power generation system. Analysis and evaluation for development of extra-high efficiency solar cells (fundamental research on extra-high efficiency Si solar cells); Taiyoko hatsuden system jitsuyoka no tame no kaiseki hyoka. Chokokoritsu taiyo denchi no gijutsu kaihatsu no tame no kaiseki hyoka (chokokoritsu silicon taiyo denchi gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Sekikawa, T.; Suzuki, E.; Ishikawa, K.; Takato, H.; Yui, N.; Shimokawa, R. [Electrotechnical Laboratory, Tsukuba (Japan)

    1994-12-01

    Described herein are the results of the FY1994 research program for analysis and evaluation for development of extra-high efficiency silicon solar cells. It is necessary for development of extra-high efficiency Si solar cells to extend as far as possible service life of minority carriers and to develop the evaluation techniques. Noting photoluminescence (PL) observable even with Si, the method of evaluating characteristics of minority carriers, which are not limited in samples, is developed to experimentally determine their service life from transitional response of the PL characteristics. Si has an extremely low quantum effect, because it is an indirect transitional semiconductor, and needs measurement of very high sensitivity. A rapid heat annealing apparatus and others to generate carriers in the infrared and ultraviolet regions are provided in consideration that these are possible means to increase efficiency. These possibilities will be pursued by developing the annealing techniques. 1 fig.

  16. Analysis and evaluation for practical application of photovoltaic power generation system. Analysis and evaluation for thin substrate polycrystalline solar cells (compound semiconductors and their fabrication technologies); Taiyoko hatsuden system jitsuyoka no tame no kaiseki hyoka. Usumaku taiyo denchi jitsuyoka no tame no kaiseki hyoka (kagobutsu taiyo denchi zairyo oyobi seisaku gijutsu no kaiseki hyoka)

    Energy Technology Data Exchange (ETDEWEB)

    Oyagi, H.; Okada, Y.; Yamaguchi, H.; Shiota, T.; Kuroda, S.; Igarashi, O.; Tanino, H.; Makita, Y.; Yamada, A.; Kimura, S.; Ohara, A.; Niki, S.; Shibata, H.; Fons, P. [Electrotechnical Laboratory, Tsukuba (Japan)

    1994-12-01

    Described herein are the results of the FY1994 research program for analysis and evaluation for thin-film compound semiconductor solar cells. The study on epitaxial growth and optical properties of the thin films of CuInSe2 and CuGaSe2 evaluates the thin epitaxial films grown under various conditions, showing morphology of the defects at the interface of heteroepitaxial growth. These results are used to set the growth conditions under which a thin film of high luminescence by exciter recombination is produced. The study also gives information of luminescence transition in the vicinity of the band ends and of energy level between the bands. The study on structural analysis of the epitaxially grown thin films of CuInSe2 investigates dependence of lattice constants of the MBE-grown CIS layer on film thickness by the X-ray diffractometry based on the bond method. The study on epitaxial growth by the Se(CH3)2-halogen transfer method tests epitaxial growth of the single-crystalline Mo on a substrate of single-crystalline sapphire. 5 figs.

  17. Achievement report for fiscal 1997. Technological development for practical application of a solar energy power generation system/development of technology to manufacture thin film solar cells (development of technology to manufacture applied type thin film solar cells with new construction) (development of technology to manufacture micro light collection type solar cells); 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu, oyogata shinkozo usumaku taiyo denchi no seizo gijutsu kaihatsu (micro shukogata taiyo denchi no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    These technological developments are intended to demonstrate module efficiency of a micro light collection type solar cell of 15% by fiscal 2000, and obtain prospect on the module manufacturing cost of 140 yen per watt. Discussions given during fiscal 1997 are as follows: development has been performed on a design method to decide construction of a non-tracking micro light collection type module; in the state of cells being integrated on the module, the cells are arranged minutely and discretely, whereas, with discussions on a method to form them and assessment of the optical system as the main objective, single crystal silicon solar cells with a size smaller than 5 mm were fabricated on a trial basis; problems of forming micro cells by using the wafer cutting process were clarified; micro cells operating on light collection were fabricated trially to extract technological problems in light collecting operation and discuss technical problems in mass production; and development was performed on an evaluation method to analyze the cells' light collecting operation, and discussions were given on a method to estimate power generation amount from the light collection type modules. (NEDO)

  18. Achievement report for fiscal 1997. Technological development for practical application of a solar energy power generation system/development of technology to manufacture thin film solar cells/development of technology to manufacture low-cost large-area modules/development of technology to manufacture next generation thin film solar cells (development of technology to manufacture applied type thin film solar cells with new construction); 1997 nendo tiayoko hatsuden system jitsuyoka gijutsu kaihatsu. Usumaku taiyo denchi no seizo gijutsu kaihatsu, tei cost daimenseki module esizo gijutsu kaihatsu (jisedai usumaku taiyo denchi no seizo gijutsu kaihatsu, oyogata shinkozo usumaku taiyo denchi no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    A thin film single crystal silicon solar cell module is developed, in which a porous silicon layer is formed on the surface of a long-sized single crystal silicon substrate, a single crystal silicon film is integrated on the layer by epitaxially growing the film thereon to form a solar cell, and the solar cell is peeled off from the silicon substrate and transferred to a plastic film substrate. The achievements during this fiscal year may be summarized as follows: simultaneous formation of a porous silicon layer on a silicon substrate, reduction of anode formation current density from 200 mA/cm{sup 2} to 10 mA/cm{sup 2}, development of a silicon epitaxial device using a carbon heater, and attainment of aperture conversion efficiency of 11.8% in a thin film single crystal silicon solar cell. Three kinds of methods were developed to peel off the solar cell. A method was developed to grind silicon substrate surface from which the solar cell has been peeled off. A technology was developed to obtain a long-sized silicon substrate of about 30 cm times 10 cm times 0.1 cm from a 4-inch silicon ingot by using a wire saw. (NEDO)

  19. Development of practical application technology for photovoltaic power generation systems in fiscal 1997. Development of technologies to manufacture thin film solar cells, development of technologies to manufacture low-cost large-area modules, development of technologies to manufacture next-generation thin film solar cells (development of technologies to manufacture CIS solar cell modules); 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu. Usumaku taiyo denchi no seizo gijutsu kaihatsu, tei cost daimenseki module seizo gijutsu kaihatsu, jisedai usumaku taiyo denchi no seizo gijutsu kaihatsu (CIS taiyo denchi module no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Research and development was made with an objective to achieve conversion efficiency of 13% in a 30 cm times 30 cm size submodule of a CIS-based thin film solar cell, and to develop a manufacturing technology that can achieve 140 yen/Wp. This paper describes the achievements attained during fiscal 1997. In fiscal 1997, based on the achievements reached during the previous year, a submodule with a size of 10 cm times 30 cm was fabricated for an attempt of improving the open voltage and short circuit current density. Simultaneously, the applicability thereof to a module with an area as large as 30 cm times 30 cm was evaluated. As a result of experimental discussions, enhancement in the open voltage was verified by increasing amount of Ga or sulfur, but it was not possible to achieve 600 mV or higher. In the research of component technologies to establish a mass production process, research and development was made on a high-resistance buffer layer film forming technology, a high-quality window layer film forming technology, a high-quality metallic rear electrode film forming technology, and patterning technologies. The outdoor exposure test was continued on laminated mini-modules with a size of 10 cm times 10 cm. (NEDO)

  20. Development of technology for thin substrate polycrystalline solar cells for practical use. Survey on analysis for practical use; Usugata takessho taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Jitsuyoka kaiseki ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the survey results on the manufacturing technology trend of thin substrate solar cells for practical use in fiscal 1994. In production of Si raw material, as electron beam melting and ingot production are combined, C, P, Ca and Al are removed by evaporation, while Fe and Ti by solidifying segregation. As the basic technology of continuous casting for substrate production, a drop coagulation method for Si melt is under investigation which is more advantageous in unidirectional solidification and cell conversion efficiency than conventional methods. The cost and future of single crystal Si and polycrystal Si were compared on the basis of document survey. Every institute commonly uses FZ substrates to produce single crystal Si cells, and SiO2 for surface passivation. New cell structure, hetero-structure, thin cell, crystalline defect and lifetime are under investigation for ultrahigh-efficiency solar cells. The technology trend was also surveyed through academic societies and conferences. 5 tabs.

  1. Research and development of evaluation system for photovoltaic power generation system. Research and development of evaluation systems for photovoltaic cells and modules; Taiyoko hatsuden system hyoka gijutsu no kenkyu kaihatsu. Taiyo denchi hyoka system no kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on R and D of the evaluation system for solar cells in fiscal 1994. (1) On development of the performance evaluation method for solar cells, data collection, analysis and measurement of atmospheric conditions necessary for outdoor measurement were carried out to improve the measurement accuracy of laminated solar cells. The validity of measurement methods was verified by comparing experimental results with outdoor measurement ones to improve the indoor measurement accuracy by multiple light source solar simulator. Generated energy in solar cell module level was also studied in field. (2) On development of the reliability evaluation method for solar cells, deterioration data were collected and analyzed by long-term exposure test. As a result, it was clarified that Pmax values are directly affected by seasonal change in air mass, and deterioration of solar cells is hardly found after exposure test for one year, showing a stable state. The characteristic recovery experiment of amorphous solar cell modules was carried out, and the accelerated deterioration test method of thin film cell modules was also studied. 2 figs.

  2. Achievement report for fiscal 1997 on development of technologies for practical photovoltaic system under New Sunshine Program. Manufacture of thin-film solar cell / low-cost and large-area module / next-generation thin-film solar cell (Manufacture of thin-film polycrystalline solar module); 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu, tei cost daimenseki module seizo gijutsu kaihatsu, jisedai usumaku taiyo denchi no seizo gijutsu kaihatsu (usumaku takessho taiyo denchi module no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Fiscal 1997 is the first year of another 4-year-long research and development phase. In addition to researches for improving on thin-film polycrystalline Si cell efficiency that have been under way, new efforts are started, which include the development of practicality-conscious thin film producing technologies aiming at higher throughput and yield and the development of modularization process technologies which are necessary for putting thin-film cells to practical use. Concerning the formation of a power generation layer on a polycrystalline Si thin film formed by the ZMR (zone-melting recrystallization) process, studies are conducted for improvement on its throughput and yield using a new CVD (chemical vapor deposition) unit. A method of modularization is evaluated, which involves a laminate of a thin-film cell attached to a resin-coated, reinforced glass substrate and an EVA (ethylene vinyl acetate) back film. A remarkable achievement is earned toward the practicalization of technologies of thin film formation enhanced in quality and throughput and technologies of thin film modularization. (NEDO)

  3. Research and development of evaluation system for photovoltaic power generation system. Survey on research and development of solar cell evaluation system; Taiyoko hatsuden system hyoka gijutsu no kenkyu kaihatsu. Taiyo denchi hyoka system no kenkyu kaihatsu chosa

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the survey results on R and D of solar cell evaluation systems in fiscal 1994. The performance/reliability evaluation subcommittee continuously analyzed technical issues and discussed solution measures from the last fiscal year. On development of performance evaluation methods, improvement of measurement accuracy for laminated solar cells is the study issue to be solved. Although laminated solar cells are measured by multiple light source solar simulator, difficult spectrum compensation causes measurement errors. Collection and analysis of data for determining atmospheric conditions, and outdoor measurement experiment under the atmospheric conditions for reference solar light were carried out. The study on incident angle characteristics of laminated solar cells clarified that the deviation from COS characteristics is 1.0% or less at an incident angle of 30{degree}. The study on generated energy in solar cell module level in field clarified that generated energy and generation efficiency are proportional to intensity of solar radiation. 1 tab.

  4. Research on fabrication technology for thin film solar cells for practical use. Survey on the commercialization analysis; Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Jitsuyoka kaiseki ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the survey results on the technological trend, safety and latest technologies of thin film solar cells in fiscal 1994. As the fabrication technology for amorphous film solar cells, three-electrode plasma CVD was surveyed as fabrication method for high-mobility materials, and hydrogen radical CVD as fabrication method for high-photostable films. Current foreign and domestic reliability tests were surveyed for reliability evaluation of solar cells. In order to ascertain the performance, efficiency, physical properties and optimum structure of polycrystalline Si thin film solar cells, previously reported test results on physical properties such as carrier concentration, carrier lifetime and mobility of films were surveyed together with device simulation results. In addition, technologies for high-efficiency CuInSe2 system and CdTe system solar cells, technologies for cost reduction and mass production, and environmental influence were surveyed. Estimation of production costs for cell modules, and safety of thin film solar cells were also surveyed.

  5. Change of the equivalent circuit constants accompanied by the degradation and recovery of efficiency on a-Si solar cells; A-Si taiyo denchi no koritsu no rekka to kaifuku ni tomonau toka kairo teisu no henka

    Energy Technology Data Exchange (ETDEWEB)

    Takahisa, K.; Kojima, T.; Nakamura, K.; Koyanagi, T.; Yanagisawa, T. [Electrotechnical Laboratory, Tsukuba (Japan)

    1997-11-25

    Investigations were given on how the equivalent circuit constants change when efficiency of amorphous silicon solar cells changes with time in light degradation and temperature recovery. In the experiment, light irradiation tests under a constant temperature and light intensity condition, followed by recovery tests under a constant temperature and constant weak light intensity or constant temperature condition were repeated continuously. According to the result of an experiment on single layer type cells, the change in each equivalent circuit constant in association with degradation in efficiency and file factor and variation in recovery is reversible mostly. However, a slightly irreversible component was recognized only in the initial degradation process in series resistance and diode factor values. With regard to stacked cells, it was suggested that the main players to determine cell characteristics during the processes of deterioration and recovery take turns among the three layers as follows: the shape of the time-based change in the efficiency comes different and is not saturating; as the efficiency decreases, the extent of the change increases in the diode factor and series resistance; and the path the deterioration takes differs from that the recovery takes. 2 refs., 12 figs.

  6. 29th Solar Energy Promotion Committee Meeting - 4th Solar Cell Liaison Meeting. (Report for fiscal 1991); Dai 29 kai taiyo energy suisuin iinkai dai 4 kai taiyo denchi renrakukai. 1991 nendo hokoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-04-21

    The above-named events took place in Tokyo in the period of April 21-24, 1992, and a total of 55 essays were presented. Presented in the session of the thin-film/a-Si systems were 27 essays, which were 'Light-induced degradation and its mechanism in a-Si:H and its multilayers,' 'Light-induced ESR (electron spin resonance) in a-Si{sub 1-x}N{sub x}:H,' 'Distribution of hydrogen surrounding light-induced defects,' 'Equilibration temperature and hydrogen diffusion in a-Si:H,' etc. Presented in the session of the thin-film compound systems were 6 essays, which were 'Local structure studies of CuInSe{sub 2} thin films,' 'Characterization of CuInSe{sub 2} bilayer films fabricated by ICB (ionized cluster beam) techniques,' etc. Presented in the session of the crystal compound systems were 7 essays, which were 'heteroepitaxy of In{sub x}Ga{sub 1-x}As/GaAs,' 'cell efficiency calculation for optimization of cell structure,' etc. Presented in the session of the crystal/Si systems were 15 essays which were 'Preparation of textured AR film,' 'Development of amorphous/thin film polycrystalline silicon tandem cell,' 'Development of high efficiency polycrystalline silicon thin-film solar cells,' 'Production of SOG (spin on glass)-Si from metallic grade silicon,' etc. (NEDO)

  7. Fiscal 1999 research and development of technologies for practical application of photovoltaic power generation systems. Development of ultrahigh-efficiency crystalline compound solar cell manufacturing technology (Survey of peripheral element technologies - Survey of environmental adaptation of next-generation solar cell development); 1999 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Chokokoritsu kessho kagobutsu taiyo denchi no seizo gijutsu kaihatsu (shuhen yoso gijutsu ni kansuru chosa kenkyu - jisedai taiyo denchi kaihatsu kankyo tekioka chosa)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Surveys are conducted of photovoltaic power system development projects and their utilization in Japan and overseas, and a discussion is made on the progress, technical challenges, effects, and implementation systems relating to the solar cell application technology development project under the New Sunshine Program. Compiled in the report are the results of surveys of the research and development of photovoltaic power systems and their diffusion in the U.S. and European nations, and the research and development strategies for and the trends of the development of various types of solar cells in these countries. The trends of research and development of non-conventional type solar cells are also collected, which include 3 cases of TPV (thermophotovoltaic) devices, 5 cases of new inorganic materials, 1 case of new organic materials, and 4 cases of dye-sensitized solar cells. In relation to the status of resources of crystalline compound-based solar cell materials, raw materials for solar cells other than silicon are taken up, and their reserves, manufacturing methods, quantities yielded and consumed, costs, etc., are surveyed. These are all taken into consideration in discussing the basic approach to the study of future research and development as it ought to be. (NEDO)

  8. 32nd Solar Energy Promotion Committee Meeting - 7th Solar Cell Liaison Meeting. Report for fiscal 1994; Dai 32 kai taiyo energy suishin iinkai dai 7 kai taiyo denchi renrakukai (1994 nendo hokoku)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-24

    The above-named events were convened in the period of April 24-27, 1995, when a total of 77 presentations were given on research achievements. In the session on thin type Si polycrystalline systems, 12 essays were presented concerning the thermodynamics of phosphorus and titanium in silicon, etc. In addition, a discussion was held on the 'Technological tasks remaining to be discharged toward industrialization.' In the session on thin film polycrystalline silicon systems, 5 essays were presented and 'Technological tasks related to thin film polycrystalline silicon solar cell' was discussed. In the session on ultrahigh efficiency Si systems, 5 essays were presented and 'Tasks related to the development of ultrahigh frequency single crystal Si solar cell' was discussed. At the symposium, 'Adoption of new energy to be accelerated following the formulation of the New Energy Introduction Guidelines' and 'Outlook for thin film solar cell practical application' were taken up. Various essays were presented and a discussion was held in each of the other sessions on ultrahigh efficiency III-V group systems, thin film chalcopyrite/II-VI group systems, international collaboration, matters related to systems, and thin film a-Si systems. (NEDO)

  9. Dependence of open-circuit voltage of SnO2-nSi solar cells; SnO2-nSi taiyo denchi no sanka ondo menhoi izonsei

    Energy Technology Data Exchange (ETDEWEB)

    Shinoda, S.; Shimizu, A.; Yano, K.; Kasuga, M. [Yamanashi University, Yamanashi (Japan). Faculty of Engineering

    1997-11-25

    Although metal(or semiconductor)-semiconductor solar cells, SnO2-nSi solar cell for example, are superior in cost and efficiency, its barrier height and open-circuit voltage V(oc) are lower than those of p-n junctions. To improve these defects, study was made on the dependence of V(oc) on oxidation temperature and surface orientation using various solar cells prepared from (100)Si and (111)Si under various oxidation conditions. As a result, the density of surface states increases with a decrease in oxidation temperature of Si substrates, resulting in an increase in diode factor and V(oc). In this case, since oxide films are extremely thin and contribution of non-terminated bonds is large in the initial oxidation stage, the quantity of dangling bonds is larger in (100) plane than (111) plane, resulting in an increase in diode factor and V(oc). Since the surface energy level (the degree of electrons dominated by acceptor-like surface state from this level to the top of a valence band) of (100) Si is lower than that of (111) Si, the effective barrier height and V(oc) increase. 28 refs., 6 figs., 2 tabs.

  10. 31st Solar Energy Promotion Committee Meeting - 6th Solar Cell Liaison Meeting. Report for fiscal 1993; Dai 31 kai taiyo energy suishin iinkai dai 6 kai taiyo denchi renrakukai (1993 nendo hokoku)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-04-25

    The above-named events were convened in the period of April 25-28, 1994, when a total of 71 presentations were given on research achievements. Presented in the session on thin film systems were 21 essays concerning the low cost manufacturing technology of low-area modules, development of film substrate a-Si solar cells, etc. Discussed at the symposium were the 'Autonomous development of photovoltaic power generation' and 'Practical application and research and development.' Presented in the session on crystalline Si systems were 17 essays concerning real-time observation of epitaxial growth using STM (scanning tunneling microscope), research on single crystal silicon manufacturing technology, etc. Discussed in the session on international cooperation was 'How international joint research should be.' Presented in the session on systems were 11 essays including the research and development of photovoltaic modules integrated with construction materials. Presented in the session on III-V group systems were 7 essays including the development of crystallized compound solar cell technology. Presented in the session on chalcopyrite II-VI group systems were 9 essays including the development of large area CdS/CdTe solar cell. (NEDO)

  11. FY 1999 research and development of technologies for commercialization of photovoltaic power generation systems. Development of technologies for production of thin-film solar cells and low-cost, large-area modules (Development of technologies for high-reliability CdTe solar cell modules); 1999 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu / tei cost daimenseki module seizo gijutsu kaihatsu (koshinraisei CdTe taiyo denchi module no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    The research and development project is implemented for production of low-cost, large-area modules of CdTe solar cells by the high-quality film-making process and high-function patterning, and the FY 1999 results are reported. The research program for the large-area TCO film-making technologies involves investigations on improvement of SnO{sub 2} film quality by the mist method and continuous film-making, which lead to continuous, stable production of 34 substrates of low resistance of 9.7{omega} on the average. The program for production of the large-area, thin-film CdS/CdTe solar cells involves production of TCO and CdS by the mist method, and patterning of the laminated TCO/CdS film by laser scribing. The CdTe film is formed by the atmospheric pressure CSS method, and treated with CdCl{sub 2} to improve its crystallinity. The CdTe film is patterned by sand blasting, and provided with the carbon and silver electrodes by screen printing, to complete the cell. The process is totally effected at the atmospheric pressure, needing no vacuum device. The CdTe solar cell assembly (130 cells connected in series, opening area: 5,413cm{sup 2}), fabricated on a trial basis, achieves a conversion efficiency of 10%. (NEDO)

  12. Development of practical application technology for photovoltaic power generation systems in fiscal 1997. Development of technologies to manufacture next-generation thin film solar cells, development of technologies to manufacture CIS solar cell modules, development of technologies to increase high-quality film area; 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu. Jisedai usumaku taiyo denchi module no seizo gijutsu kaihatsu, CIS taiyo denchi module no seizo gijutsu kaihatsu, kohinshitsumaku no daimensekika gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    With an objective to improve efficiency and reduce cost of CIS-based thin film solar cells, research and development has been made on technologies to increase high-quality CIS film area and technologies to increase speed in the manufacturing process. This paper describes the achievements attained during fiscal 1997. The research covered development of technologies to form high-grade Cu (In, Ga) Se{sub 2} (CIGS) film by using the multi-dimensional deposition process, component technologies for forming a rear electrode, a buffer layer and a transparent electrode, and patterning technologies. As a result of the research, thickness of the CIGS film was reduced to half as much as that of the conventional films, having achieved conversion efficiency of 13.1%, which corresponds to about 90% of the conventional CIGS solar cells. In addition, elucidation was made on the effect of an MoSe{sub 2} layer existing on interface with CIGS/Mo in a CIGS solar cell imposed on solar cell characteristics. In developing an Mo film laser scribing technology, intensity dependence of laser energy was made clear, the energy being required for scribing according to surface condition of the Mo film. (NEDO)

  13. Achievement report for fiscal 1997 on developing practical application technology for photovoltaic power generation systems under the New Sunshine Project. Development of technologies to manufacture thin film solar cells, development of technologies to manufacture low-cost large-area modules, and development of technologies to manufacture new type amorphous solar cells; 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu. Usumaku taiyo denchi no seizo gijutsu kaihatsu, tei cost daimenseki module seizo gijutsu kaihatsu, shingata amorphous taiyo denchi no seizo gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Development will be made on high-performance a-solar cells as part of developing practical application technology for a-solar cells for electric power use. Development will be also made on a low-cost process technology. This paper describes the achievements attained during fiscal 1997. Quality improvement has been realized by using a high RF power hydrogen dilution process on a-Si films for front cells of lamination type cells. Four times faster film forming speed was obtained even by using the VHF plasma CVD process, with film quality equivalent to those made by using the conventional RF process maintained. By optimizing the light enclosing construction, the short circuit current was enhanced by over 20%. Discussions were given on forming homogenous a-Si films by optimizing the conditions for forming films on large-area substrates, which resulted in forming film of 30 cm times 40 cm size with good homogeneity at a film forming speed three times faster than the conventional speed. A surface electrode was formed successfully with good uniformity on a substrate with a size of 60 cm times 90 cm. Productivity greater by over three times the conventional productivity was achieved in patterning of transparent electrodes by using high-output laser. Simultaneous and collective patterning and very small and long size collective patterning were realized in a-Si film selection patterning by using the plasma CVD process. (NEDO)

  14. Changes of the temperature coefficients of the characteristics which accompany degradation and recovery of a-Si solar cells; A-Si taiyo denchi no hikari (denryu) rekka oyobi kaifuku ni tomonau tokusei ondo keisu no henka

    Energy Technology Data Exchange (ETDEWEB)

    Yanagisawa, T.; Koyanagi, T.; Nakamura, K.; Takahisa, K.; Kojima, T. [electrotechnical Laboratory, Tsukuba (Japan)

    1996-10-27

    Pursuant to the measuring of temperature dependency of the characteristics such as conversion efficiency, during the process of degradation in a-Si solar cells due to light and electric current and the process of recovery by annealing, this paper describes changes in temperature coefficients, correlation between the characteristic parameters and the degradation, and the results of the examination of their characteristics. The conversion efficiency {mu} degraded approximately by 45% of the initial value each by the irradiation under a light intensity with 3 SUN accelerated and by the infusion of current at 20mA/cm{sup 2}; and then, the efficiency recovered to 70-75% of the degradation by subsequent annealing. In addition, in the temperature dependency at 80{degree}C against at 20{degree}C, Isc slightly increased while Vcc greatly decreased. This slight increase in Isc was mainly due to the decrease in the width of the forbidden band, while the decrease in Vcc was due to the increase in the reverse saturation current. The temperature dependency of {mu}N was negative, becoming small in accordance with the degradation. The temperature dependency of FF/FFO was negative initially both in light and current, but it decreased with the degradation and turned to positive. The temperature coefficients of I-V parameters reversibly changed corresponding to the degradation and recovery of these parameters and stayed in a good correlation. 7 refs., 8 figs., 1 tab.

  15. Achievement report for fiscal 1997 on development of technologies for practical photovoltaic system under New Sunshine Program. Manufacture of thin-film solar cell and of low-cost/large-area module (Manufacture of high-reliability CdTe solar module); 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi no seizo gijutsu kaihatsu, tei cost daimenseki module seizo gijutsu kaihatsu (koshinraisei CdTe taiyo denchi module no seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The target is a low-cost CdS/CdTe solar cell of a large area (60cm times 90cm), the establishment of mass-production technologies for the cell, and the enhancement of production efficiency. A thin film formation technology of subjecting CdS film organic metal to pyrolysis is established, which reduces photoabsorption loss in the shortwave domain of wavelength of not longer than 500nm, reduces reflection loss in the film, and improves on short-circuit current density. Improvement is also achieved on CdTe film quality and junction quality by use of a proximity sublimation method in a vacuum, when a conversion rate of 16.0% (1cm{sup 2}) is attained which is the highest in the world. Based on the results of the above-said efforts, a 3.3mm-thick glass substrate is employed for CdTe film to develop into a 30cm times 60cm-large size, with the film thereon uniformly thick over a large area thanks to a normal pressure proximity sublimation method. Studies are made toward a process nearer to the ultimate product and, using the patterning technique, a 30cm times 60cm-large CdTe solar cell is tentatively built realizing a conversion rate of 9.8%. (NEDO)

  16. Development of technology for thin substrate polycrystalline solar cells for practical use. Development of elementary technologies for low-cost polycrystalline cell modules; Usugata takessho taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Takessho cell module tei cost ka yoso gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on development of elementary technologies for low-cost polycrystalline cell modules in fiscal 1994. (1) On development of elementary technologies for mass production, fast surface machining, fast electrode forming and fast forming of junctions and antireflection films were studied. Surface machining by rotating grindstone was studied as fast cutting of fine grooves on Si substrates, resulting in possible fast machining superior in shape accuracy. Electrode properties equivalent or superior to previous ones were obtained by fast electrode forming using a fast printing/sintering equipment even at transfer speed 7.5 times as high as that of conventional methods. Simultaneous fast forming of junctions and antireflection films were achieved by heat treatment after deposition on Si substrate surfaces while heat-decomposing Ti and P compound gas. (2) On development of module structure, an optimum cell group angle, low reflection rate at glass surface, and fast wiring were studied. 5 figs., 2 tabs.

  17. Achievement report for fiscal 1997. Technological development for practical application of a solar energy power generation system /development of technology to manufacture solar cells/development of technology to manufacture thin film solar cells (development of technology to manufacture materials and substrates (development of technology to manufacture silicon crystal based high-quality materials and substrates)); 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Taiyo denchi seizo gijutsu kaihatsu, usumaku taiyo denchi seizo gijutsu kaihatsu, zairyo kiban seizo gijutsu kaihatsu (silicon kesshokei kohinshitsu zairyo kiban no seizo gujutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    It is intended to develop thin film solar cells capable of mass production with high photo-stability and at low cost. Thus, the objective of the present research is to analyze the growth process of micro crystal silicon based thin films, the crystal being a high quality silicon crystal based material, and develop technology to manufacture high-quality micro crystal silicon thin films based on the findings therefrom. It was found that, when silicon source is available in cathode, pure hydrogen plasma forms micro crystal silicon films by using the plasma as a result of the chemical transportation effect from the silicon source. It was revealed that the crystal formation due to hydrogen plasma exposure is performed substantially by the crystals forming the films due to the chemical transportation effect, rather than crystallization in the vicinity of the surface. The crystal formation under this experiment was concluded that the formation takes place during film growth accompanied by diffusion of film forming precursors on the surface on which the film grows. According to the result obtained so far, the most important issue in the future is particularly the control of crystal growing azimuth by reducing the initially formed amorphous layer by controlling the stress in the initial phase for film formation, and by controlling the film forming precursors. (NEDO)

  18. Development of practical application technology for photovoltaic power generation systems in fiscal 1997. Development of technologies to manufacture ultra high efficiency crystal compound solar cells; 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu. Chokokoritsu kessho kagobutsu taiyo denchi no seizo gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Research and development was made for the purpose of achieving by the end of fiscal 2000 conversion efficiency of 30% or higher in a 5-cm square tandem solar cell using hypercomplex compound semiconductors, and establishing a new low-cost cell structure. In developing a large area cell manufacturing technology, a totally organic MOCVD process was used for epitaxial growth for forming the cell structure in manufacturing a 2.5-cm square GaInP single junction cell. Conversion efficiency of 13.1% was attained, but this is still insufficient as the conversion efficiency for a top cell. In the epitaxial growth in the GaAs cell structure, conversion efficiency as good as 22.1% was obtained. Also for a GaInAs cell being a bottom cell, a 2.5-cm square cell was fabricated on a trial basis. When a GaAs/GaAs laminated cell is formed by using the mechanical stacking method, the conversion efficiency has risen to 27.5% in total, thus having nearly achieved the goal for fiscal 1997. Fundamental discussion has begun on epitaxial growth of GaInNAs and nitride mixed crystal, which has a possibility as a new bottom cell material. (NEDO)

  19. Analysis and evaluation for practical application of photovoltaic power generation system. Research and development of elemental technologies for thin-type solar cells; Taiyoko hatsuden system jitsuyoka no tame no kaiseki hyoka. Usugata takessho taiyo denchi jitsuyoka no tame no kaiseki hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Sekikawa, T.; Shimokawa, R.; Yui, N.; Takato, H.; Takahashi, T.; Ishii, K.; Suzuki, E.; Nagai, K.; Kawanami, H.; Tanimoto, J.; Sakuta, H.; Iwata, Y.; Saito, N.; Koyama, K.; Sawada, S. [Electrotechnical Laboratory, Tsukuba (Japan)

    1994-12-01

    Described herein are the results of the FY1994 research program for analysis and evaluation for thin substrate polycrystalline solar cells. In order to analyze the structures of the grain boundaries in and interfaces with the cell substrate, and their effects on electrical activity, the photoluminescence (PL) measurement which enables spectroscopic analysis is applied to electromagnetically cast Si crystals. There are good correlations among PL luminous intensity, MBIC output and dislocation density for the grain boundary which contains many strains and serves as the dislocation source, because carriers in such a grain boundary easily disappear to reduce its luminous intensity at the band ends. Concrete scenarios for realizing thin-film silicon solar cells of high efficiency are presented, based on the analysis of the light-contained thin-film silicon solar cells of high output current, made in the previous year on a trial basis. An alumina substrate of high reflectivity is produced by the experiments of combining various devices. It is expected to realize high output current for the thin-film solar cells. 3 figs.

  20. Achievement report for fiscal 1997 on developing a silicon manufacturing process with reduced energy consumption. Investigation and research on analyzing practical application of a technology to manufacture solar cell silicon raw materials; 1997 nendo energy shiyo gorika silicon seizo process kaihatsu. Taiyo denchi silicon genryo seizo gijutsu no jitsuyoka kaiseki ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    This paper describes the achievement in fiscal 1997 of analyzing practical application of a technology to manufacture solar cell silicon raw materials. Silicon consumption for solar cells in fiscal 1997 has increased to 2000-ton level, and the supply has been very tight. For drastic improvement in the demand and supply situation, development of SOG-Si manufacturing technology and its early practical application are desired. The development of the NEDO mass-production technology using melting and refining has completed constructing the process facilities in fiscal 1998, and will enter the stage of operational research. However, insufficiency in the basic data about behavior of impurities is inhibiting the development. In the substrate manufacturing technology, discussions have shown progress on use of diversifying silicons outside the standard by using the electromagnetic casting process. For slicing and processing the substrates, development of a high-performance slicing equipment and automatic rough rinsing machine is under way. Properties required on silicon raw materials vary considerably widely because of difference in cell making systems and conditions, which is attributable to unknown impurity behavior. When 1GW production is assumed, the cell module manufacturing cost is calculated as 137 yen/W, for which low-cost mass production for its realization, slicing productivity enhancement, and cost reduction are required. The paper also describes site surveys in overseas countries. (NEDO)

  1. Research and development of system to utilize photovoltaic energy. Survey on the high-durability and low-cost materials for constructing the solar-cell module and its structure; Taiyoko hatsuden riyo system no kenkyu. Taiyo denchi module yo kotaikyusei tei cost zairyo, kozo ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the results obtained during fiscal 1994 on a survey on the high-durability and low-cost materials for constructing the solar-cell module and on its structure. With respect to forms and materials used in the present solar-cell modules, identification was made on the current status of products commercially available and developed inside and outside Japan. Main types of solar cells used for electric power are of crystal-based silicon. Amorphous silicon and CdS-CdTe are used for consumer applications of indoor and outdoor use. As regards transparent resin materials, fluorine resin, PET, acryl, and polyimide are used as surface materials, and EVA, silicon and PVB are often used as fillers. Developments inside and outside Japan are limited to systems of polycarbonate, methacryl, fluorine, polyurethane, acryl and polyester. Butyl rubber and polyurethane are used as sealing materials. Developments are being performed on silicon rubber, polychloroprene rubber and EPT rubber for shaped materials, and silicon systems, urethane systems and polysulfide systems for non-shaped materials. 3 figs., 8 tabs.

  2. Development of technology for thin substrate polycrystalline solar cells for practical use. Development of manufacturing technologies for low-cost substrates (technical development for production of high purity silicon); Usugata takessho taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Tei cost kiban seizo gijutsu kaihatsu (taiyo denchiyo silicon seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on development of manufacturing technologies of Si for solar cells in fiscal 1994. (1) P in Si could be successfully reduced to 0.1ppmw by EB melting method. The condition possible to reduce P in Si while continuously supplying metal Si was found. The 20kg class EB melting equipment was also designed and manufactured which can be connected with solidifying rough refining process. (2) Use of a water-cooling copper mold was studied using a small melting equipment for cost reduction in solidifying rough refining process. As a result, the prospect of crucible-free technology for removal of P and solidifying rough refining was obtained. (3) B in Si could be successfully reduced to the target of 0.1ppmw by vapor addition method using a plasma melting equipment. (4) The prototype SOG-Si achieved a conversion efficiency of 14.1% as solar cell. In addition, the advanced solar cell prepared by efficiency enhancement process achieved a conversion efficiency of 15.9%. 3 figs.

  3. Development of technology for thin substrate polycrystalline solar cells for practical use. Development of manufacturing technologies for low-cost substrates (low-cost Si sheets by continuous casting method); Usugata takessho taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Tei cost kiban seizo gijutsu kaihatsu (renzoku cast ho ni yoru tei cost Si kiban seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on manufacturing of low-cost Si substrates by continuous casting method in fiscal 1994. (1) On manufacturing of ingots of 16 piece size, the ingot of nearly 170kg was manufactured by batch process using the Si melt injection unit prepared in last year. (2) On oxygen and carbon contents in wafers, the contents were measured by FT-IR after slicing of the ingot. As a result, the oxygen and carbon contents could be successfully reduced to the targets of 10ppma and 5ppma or less, respectively. (3) The resistivity distribution of the ingot ranged over the target of 1-2ohm-cm. (4) Cells of 100 {times} 100mm{sup 2} wide and 350{mu}m thick were verified by in-house evaluation process. Although lower cell conversion efficiency was found at the center top of the ingot, a vertical efficiency stability was nearly sufficient as a whole. (5) On the crystal growth unit prepared in fiscal 1994, any problems were not found on automatic driving and vibration during moving. 8 figs.

  4. New Sunshine Program for fiscal 2000. Development of photovoltaic power system commercialization technology (Development of ultrahigh-efficiency crystalline compound solar cell manufacturing technology - Surveys and studies of peripheral key technologies/Surveys of environmentally-friendliness enhancement for next-generation solar cell development); 2000 nendo New sunshine keikaku seika hokokusho. Taiyoko hatsuden system jitsuyoka gijutsu kaihatsu - Chokokoritsu kessho kagobutsu taiyo denchi no seizo gijutsu kaihatsu (Shuhen yoso gijutsu ni kansuru kenkyu chosa, Jisedai taiyodenchi kaihatsu kankyo tekioka chosa)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Though the trends of solar cell development are becoming increasingly diverse across the world, yet none has emerged to promise a stable solar cell supply in the future. Under the circumstances, studies were conducted to clarify strategies for solar cell technology development which would be well adapted to Japan's social environments, with the trends of development in the United States and European countries taken into consideration. The surveys covered the research and development and diffusion of photovoltaic power generation in the United States and European countries, and their solar cell research and development strategies and trends of development were put together. Surveys were also conducted into the research and development of unconventional types of solar cells, such as the dye-sensitized solar cell, organic solar cell, conjugate polymer solar cell, and the polymer/C{sub 60} based solar cell, and into the status of resources of materials for solar cells such as gallium, arsenic, cadmium, tellurium, indium, selenium, and germanium. Regarding the future of photovoltaic power generation research and development, it was concluded that commercialization technology development and basic research and development should continue. Also pointed out was the importance of the enlargement of the market for photovoltaic power generation systems. (NEDO)

  5. Alternative fuels. Daitai nenryo

    Energy Technology Data Exchange (ETDEWEB)

    Kim, E. (Japan Automobile Research Inst. Inc., Tsukuba (Japan))

    1992-05-05

    Evaluation of alternative fuels has been conducted by various agencies since the first oil crisis in 1973 and at that time, the development of coal, oil shale, tar sand and such synthetic fuels as coal liquefaction oil etc. was pursued in several countries like Japan and the U.S.A. as national projects. However, since the second oil crisis, due to the progress of energy saving and other measures, demand and supply of petrolium has been relaxed and synthetic oil development projects have greatly been reduced in Japan as well as other countries. At the present, because of the environmental problems, the stress has been shifted to natural gas whose cost is lower than that of coal and whose exhaust gas is expected to be cleaner than that of coal. In this article, with regard to methanol and compressible natural gas which are most expected domestically as well as overseas as alternative fuels, evaluation from the viewpoint of character, evaluation from the viewpoint 'of utilization technique and evaluation from the viewpoint of production and supply are discussed respectively. 3 refs.

  6. Achievement report for fiscal 1997 on development of technologies for practical photovoltaic system under New Sunshine Program. Manufacture of thin-film solar cell and of low-cost/large-area module (Formation of low-temperature film); 1997 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usukau taiyo denchi no seizo gijutsu kaihatsu, tei cost daimenseki module seizo gijutsu kaihatsu (teion maku keisei gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    A polycrystalline Si thin film formation technology is developed, which uses the flux process in which a reaction occurs between the target crystal and a flux component which is eutectic. Using this process, a crystal grain relatively large in diameter is obtained at a relatively low temperature. This method is now attracting attention as one of the technologies for producing crystalline Si film for use in thin-film polycrystalline Si solar cells. Especially when Al is used for flux, since Al is automatically doped into the target crystalline Si film, it is expected that the resulting film will serve as the ground for a photoactive layer provided with the BSF (back surface field) function which is important for the improvement of solar cell efficiency. A polycrystalline Si thin film is formed on a 2cm times 2cm-large glass substrate at a temperature not higher than 600 degrees C. It is recognized that films selectively oriented towards the (111) or (100) plane are acquired when other processes are employed. It is expected that the said Al-doped film provides a ground on which a BSF function-provided photoactive layer will be formed. (NEDO)

  7. Analysis and evaluation for practical application of photovoltaic power generation system. Analysis and evaluation for thin substrate polycrystalline solar cells (alloy-base amorphous materials, PIN layers, strains in the interface, and effects of impurities); Taiyoko hatsuden system jitsuyoka no tame no kaiseki hyoka. Usumaku taiyo denchi jitsuyoka no tame no kaiseki hyoka (gokinkei amorphous zairyo pin kakuso kaimen ni okeru yugami fujunbutsu nado no eikyo)

    Energy Technology Data Exchange (ETDEWEB)

    Matsuda, A.; Oeda, H.; Yamasaki, S.; Hata, N.; Kondo, M.; Toshima, Y.; Sakata, I.; Ganguly, G.; Suzuki, A.; Kamei, T.; Okushi, H.; Nonaka, H.; Oda, N.; Katagiri, H.; Ichimura, N.; Kokubu, K.; Nakamura, K.; Sekikawa, T.; Yamanaka, M. [Electrotechnical Laboratory, Tsukuba (Japan)

    1994-12-01

    Described herein are the results of the FY1994 research program for analysis and evaluation for thin film solar cells. The study on quantitative analysis of hydrogen atoms in a plasma determines quantity of hydrogen atoms in the plasma of monosilane diluted with hydrogen. It is found, contrary to expectation, that quantity of hydrogen atoms in the plasma decreases as it is more diluted with hydrogen. The study on light-induced degradation of the thin chlorine-base amorphous silicon films confirms that the plasma CVD method with 20% of dichlorosilane gas added to monosilane gas produces the thin amorphous silicon film 3 times faster than the conventional method. The thin film has essentially the same defect density as the one prepared by the conventional method, showing good photoelectric characteristics. The thin film of chlorinated amorphous silicon has a 1 digit lower defect density than the conventional one of amorphous silicon, as revealed by the accelerated degradation test with irradiated laser light and the constant current method to determine saturated defect density. 3 figs.

  8. Influence of spectral solar radiation to the generating power of photovoltaic module; Taiyo denchi shutsuryoku eno taiyoko supekutoru eno eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Minaki, S.; Ishihara, Y.; Todaka, T.; Harada, K. [Doshisha University, Kyoto (Japan); Oshiro, T.; Nakamura, H. [Japan quality Assurance Organization, Tokyo (Japan)

    1997-11-25

    As to the influence of spectral solar radiation to generating power of solar cells, a study was conducted from the aspects of season, time zone, intensity of solar radiation, etc. In the study, spectral responsive variation correction coefficients were introduced as evaluation values expressing the influence of spectral solar radiation. For the spectral distribution, an all sky spectral pyranometer by wavelength was used, and data were used which were obtained in the measurement in experimental facilities of the solar techno center. Concerning solar cell relative spectral sensitivity values, used were relative spectral sensitivity values of monocrystal and amorphous standard solar cells to the short-circuit current. Spectral response variation correction coefficients are coefficients correcting variations in conversion efficiency of solar cells due to changes in the spectral distribution. The changes of spectral responsive variation correction coefficients were studied using data obtained during April 1994 and March 1996. As a result, it was found that the coefficients showed large changes in summer and small ones in winter and that amorphous solar cells indicate this trend conspicuously. 3 refs., 6 figs., 3 tabs.

  9. Verification test for an electric vehicle using capacitor-battery series connection for battery load levelling; Denchi no fuka heijunka no tame no kyapashita to denchi no chokuretsu setsuzoku hoshiki wo saiyoshita denki jidosha no jissho shiken

    Energy Technology Data Exchange (ETDEWEB)

    Miyaoka, K.; Takehara, J.; Kato, S. [Chugoku Electric Power Co. Inc., Hiroshima (Japan)

    1998-03-25

    For the prolongation of the distance that an electric vehicle (EV) can cover on a single charge and of the service life of the EV battery unit, a system is developed, in which the battery unit and the capacitor unit are connected in series for the levelling-off of battery peak loads, and the system is tested aboard a running real vehicle. Installed on the real vehicle is a battery unit that is a series connection of 20 12V-38Ah seal-type lead-acid batteries, each battery consisting of two cells connected in parallel. Driving the vehicle is a DC brushless motor capable of a maximum operation of 9000rpm. Also installed is a capacitor unit that is a parallel connection of 40 2.3V-1800F capacitors, each capacitor consisting of two capacitors connected in parallel. Findings are described below. In a 0-400m acceleration test, 22.5 seconds is recorded with the capacitor unit in operation, meaning an improvement of 0.7 seconds. The maximum speed remains unchanged at 110km/h, which agrees with the pre-calculated value. Although the battery peak load reduction rate in a 15-mode drive pattern marks 23%, the distances covered on a single charge in this drive pattern turn out to be almost the same whether the capacitor unit is in operation or not. 3 refs., 15 figs., 3 tabs.

  10. Forced-circulation solar water heater using a solar battery; Taiyo denchi wo mochiita kyosei junkanshiki taiyonetsu onsuiki

    Energy Technology Data Exchange (ETDEWEB)

    Asai, S.; Mizuno, T. [Yazaki Resources Co. Ltd., Shizuoka (Japan)

    1996-10-27

    For the purpose of satisfying demands for qualitative improvement on tapwater temperature and pressure, an indirect-type solar water heater using solar cells, in which a closed type hot water storage tank connected directly to the water supply is integrated with a solar collector, was examined for its characteristics and performance. The heat collecting medium is a water solution of polypropylene glycol, which circulates through the solar collector pump, cistern, solar collector, and heat exchanger (hot water storage tank). The results of the test are summarized below. When comparison is made between the two solar collector pump control methods, the solar cells direct connection method and the differential thermo method utilizing temperature difference between the solar collector and the hot water storage tank, they are alike in collecting heat on clear days, but on cloudy days the latter collects 5% more than the former. In winter, when the heat exchanger heat transfer area is 0.4m{sup 2} large, a further increase in the area improves but a little the heat collecting efficiency. An increase in the medium flow rate and temperature, or in the Reynolds number, enhances the heat collecting efficiency. 13 figs., 6 tabs.

  11. Forced-circulation solar water heater using a solar battery; Taiyo denchi wo mochiita kyosei junkahshiki taiyonetsu onsuiki

    Energy Technology Data Exchange (ETDEWEB)

    Asai, S.; Mizuno, T. [Yazaki Corp., Tokyo (Japan)

    1997-11-25

    Optimal operation control was discussed on a forced-circulation solar water heater using solar cells not only as the power supply of a heat collecting pump, but also for controlling operation of the heat collecting pump. With this system, when the amount of power generated by solar cells reaches a sufficient level for operating the heat collecting pump, the heat collecting pump starts operation, wherein the heat collecting medium circulates in the system. The discussion was given by using simulation based on experimental expressions such as the relation expression between insolation and heat collecting medium flow rate as derived from the result of the system`s heat collecting performance test. As a result, the following conclusions were obtained: optimal insolation for activating the discussed system is from 50 to 100 W/m {sup 2}, and the heat collected within this range is within -1.5% of the collected heat amount at an optimum value; optimal activating insolation for the case of 1000 to 2000 W/m {sup 2} with low daily cumulative insolation is from 0 to 50 W/m {sup 2}, whereas the optimal activating insolation amount increases as the daily cumulative insolation amount increases; and the optimal activating insolation amount increases as water to be supplied requires higher temperature. 1 ref., 17 figs., 2 tabs.

  12. NEDO fuel/storage technology subcommittee. 18th project report meeting; NEDO nenryo chozo gijutsu bunkakai. Dai 18 kai jigyo hokokukai

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-09-01

    Taro Yamayasu, a NEDO (New Energy and Industrial Technology Development Organization) director, reports fuel and storage technologies, taking reference to the research and development of technologies relating to fuel cell power generation, cell power storage system of a novel type, ceramic gas turbine, superconductor-generated power application, wide-area energy utilization network system (urbane eco-energy system), high-temperature superconductor-supported flywheel power storage, demonstration of a novel method of load levelling, demonstration test for the establishment of a centralized control system, and so forth. Reported also is research and development involving a molten carbonate fuel cell power generation system, current status of distributed cell power storage system development (large lithium secondary storage battery technology development), current status of superconductor-generated power application technology, regenerative cycle type 2-shaft ceramic gas turbine for a 300kW-class cogeneration system, high-density latent heat transportation, and so forth. (NEDO)

  13. Research report for fiscal 1998. Research into the trends of low-carbon automotive fuel manufacturing technologies; 1998 nendo jidoshayo teitanso nenryo no seizo gijutsu doko chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Studies are made of optimum materials and methods for manufacturing low-carbon fuels for reduction in greenhouse gas emissions. When their thermal dynamic limits and the technological maturity are considered, it is inferred that no extensive improvement will be achieved by merely improving on the efficiency of the existing fuels. The use of various high-efficiency driving power sources utterly different in mechanism from the conventional ones, such as those for fuel cell-powered automobiles, and the promotion of the use of low-carbon fuels such as methanol and methane for all kinds of driving power sources including those for the said fuel cell-powered automobiles, will become necessary. The use will also be necessary of recyclable materials. The biomass resources, in particular, since they absorb CO2 gas in their growing process by virtue of photosynthesis, may be said to be free of CO2 gas emissions. They have their own problems, however, which involve the economy of energy consumed for their production, harvesting, transportation, and conversion into fuels. It is therefore required that their whole life cycle be studied before their greenhouse gas reduction effect may be correctly assessed. The quantities of resources available for the production of automotive low-carbon fuels, manufacturing technologies, etc., are first of all put in order for easy perusal. An effective way is assessed for the whole including the life cycle. (NEDO)

  14. Technological development for super-high efficiency solar cells. Technological development of solar-high efficiency singlecrystalline silicon solar cells (high quality singlecrystalline silicon substrates); Chokokoritsu taiyo denchi no gijutsu kaihatsu. Chokokoritsu tankessho silicon taiyo denchi no gijutsu kaihatsu (kohinshitsu tankessho silicon kiban no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on technological development for high quality efficiency singlecrystalline silicon substrates in fiscal 1994. (1) On electromagnetic casting/once FZ bath method, a Si single crystal of 600mm long was successfully obtained by improvement of power source frequency and furnace parts. High carbon content resulted in no single crystal including solids. In undoped electromagnetic casting ingots, resistivities over 1500ohm-cm were obtained because of effective preventive measures from contaminants. (2) On electromagnetic melting CZ method, since vibration and temperature control of melt surface by magnetic shield was insufficient for stable pulling of single crystals, its practical use was hopeless. (3) On electron beam melting CZ method, a Si single crystal of 25mm in diameter was obtained by preventive measures from evaporation of Si and influence of deposits, and improved uniform deposition distribution in a furnace. The oscillation circuit constant of power source, and water-cooling copper crucible structure were also analyzed for the optimum design of electromagnetic melting furnaces. 3 figs., 1 tab.

  15. Shunt and series resistance of photovoltaic module evaluated from the I-V curve; I-V tokusei kara hyokashita taiyo denchi no shunt teiko to chokuretsu teiko

    Energy Technology Data Exchange (ETDEWEB)

    Asano, K.; Kawamura, H.; Yamanaka, S.; Kawamura, H.; Ono, H. [Meijo University, Nagoya (Japan)

    1997-11-25

    With an objective of discussing I-V characteristics when a shadow has appeared on part of a photovoltaic module, evaluations were given as a first stage of the study on saturation current, shunt resistance and series resistance for the solar cell module. As a result of measuring change in amount of power generated in a sunny day with a shadow appearing over the solar cell module, reduction in power generation capability of about 23% was verified. In other words, the I-V characteristics of the solar cell module change largely because of existence of the shadow caused on the module. The I-V characteristics curve may be expressed and calculated as a function of the shunt resistance and series resistance. By curve-fitting measurement data for a case of changing insolation without existence of partial shadow, values of the shunt resistance and series resistance were derived. As a result, it was found that the calculations agree well with measurements. It was made also clear that each parameter shows temperature dependence. 6 refs., 10 figs., 1 tab.

  16. Study of installation of PV systems at campus; Campus ni okeru taiyoko hatsuden donyu ni kansuru kenkyu (taiyo denchi nomi wo secchishita baai no yobi kento)

    Energy Technology Data Exchange (ETDEWEB)

    Tsuboi, N.; Tanaka, H.; Okumiya, M. [Nagoya University, Nagoya (Japan)

    1997-11-25

    In terms of energy consumption, environmentality and economical efficiency in the case of installing the photovoltaic power system on the rooftop of the university campus, a comparative study was conducted with other power generation systems. As objects to be comparatively studied, selected were the all-electric type centralized space heating/cooling system, cogeneration system, nighttime heat storage system and centralized system with solar cells installed. The panel area of the PV system is 10,000m{sup 2} on the rooftop and 7,000{sup 2} on the outer wall. About data on solar radiation, average values obtained in Nagoya were used. Assessment was made in terms of energy consumption amount at the time of operation, system COP, emission amounts of CO2, NOx and SOx at the time of manufacturing and operation, initial cost, running cost, etc. As a result of the study, an effect of reducing global warming gas was admitted in the PV system. However, the initial cost of the solar cell panel was high, and the life cycle cost of the PV system was lower than other systems. 1 ref., 7 figs., 3 tabs.

  17. FY 1998 annual report on the fuel/storage working group. 19th R and D activity report; 1998 nendo nenryo chozo gijutsu bunkakai. Dai 19 kai jigyo hokokukai

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-09-01

    Summarized herein are the FY 1998 R and D activities by the fuel/storage working group, extracted from the 19th R and D activity report by NEDO. Mr. Kadoi, a NEDO's director, outlined the R and D activities for development of techniques for fuel cell power generation, development of decentralized cell power storage systems, demonstration of new load-leveling techniques, development of techniques for superlow-loss type power system components, development of techniques for ceramic gas turbines, pioneer R and D for MGC superhigh-efficiency turbine system techniques, demonstration tests for establishing centralized load controlling systems, development of techniques for network systems utilizing wide-area energy, development of techniques for application of superconductor-aided power systems, R and D for power storage aided by a high-temperature, superconducting flywheel, R and D for basic techniques for applying superconductors, and pioneer R and D for basic techniques for AC superconducting power equipment. The individual NEDO's researchers reported their results, which include outline of the fuel/storage technique development group, and current statuses of fuel cell technique development, new cell-aided power storage technique development, and superconductor technique development. (NEDO)

  18. Studies of flat-plate solar air collectors with absorber plates made of amorphous silicon photovoltaic modules; Amorphous taiyo denchi module wo shunetsuban to shita heibangata kukishiki shunetsuki no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Ito, S.; Miura, N. [Kanagawa Institute of Technology, Kanagawa (Japan)

    1996-10-27

    A light/heat hybrid air type heat collector has been developed in which heat is collected by solar cell panels. In Type 1 heat collector provided with a glass cover, two modules are connected in series and placed under a glass cover to serve as a heat collecting plate, each module built of a steel plate and two thin-film amorphous solar cells bonded to the steel plate. Air runs under the heat collecting plate. Type 2 heat collector is a Type 1 heat collector minus the glass cover. Air is taken in by a fan, runs in a vinyl chloride tube, and then through the heat collector where it is heated by the sun, and goes out at the exit. Heat collecting performance was subjected to theoretical analysis. This heat collector approximated in point of heat collection a model using a board painted black, which means that the new type functions effectively as an air-type heat collector. Operating as a photovoltaic power generator, the covered type generated approximately 20% less than the uncovered type under 800W/m{sup 2} insolation conditions. Type 1 has been in service for five months, and Type 2 for 2 months. At present, both are free of troubles such as deformation and the amorphous solar cell modules have deteriorated but a little. 4 refs., 9 figs.

  19. Study on the best utilization of solar energy. Experimental study of hydrogen generation by water electrolysis using solar battery; Taiyo energy no yuko riyo ni kansuru kenkyu. Taiyo denchi riyosui denki bunkai suiso hassei field test

    Energy Technology Data Exchange (ETDEWEB)

    Kawashima, Y.; Murai, K.; Nakai, T. [Himeji Institute of Technology, Hyogo (Japan)

    1997-11-25

    Shortcomings of solar energy are that it is subject to weather and is not available in the nighttime. The weak points may be effectively made up for when solar energy collected on a fine day is stored in the form of hydrogen energy for recovery as required. In this report, power generated by solar cells is used for the electrolysis of water for the generation of hydrogen. The amounts of the thus-generated hydrogen and hydrogen energy are determined and, on the basis of the measured amount of insolation, the solar energy availability rate (hydrogen conversion performance) is calculated. The amount of hydrogen generated in fiscal 1996 is also calculated for every month. The hydrogen generation level is quite low in the TiO2 wet type solar cell, approximately 0.2% at most. The current efficiency is fairly high in hydrogen generation using electrolysis, which is approximately 96-97%. The efficiency is higher when several units of electrolyte are connected in series until the solar cell optimum voltage is attained. A linear relationship is found between the daily summation of insolation and the amount of hydrogen generated. 1 ref., 7 figs., 2 tabs.

  20. Design and construction of radiant panel for cooling and heating with photovoltaic and thermoelectric element modules; Taiyo denchi to netsuden soshi module wo mochiita fukusha reidanbo panel no sekkei oyobi shisaku

    Energy Technology Data Exchange (ETDEWEB)

    Sato, M.; Tani, T. [Science University of Tokyo, Tokyo (Japan); Kadotani, K.; Imaizumi, H. [Komatsu Ltd., Tokyo (Japan)

    1997-11-25

    Utilizing cooling properties and current voltage characteristics of a small cooling panel using thermoelectric elements which had been fabricated previously on a trial basis, design and prototype production were executed on a large radiant cooling and heating panel driven by photovoltaic cell modules. The panel design set the cooling area to about 0.5 m {sup 2} and the number of elements to 70 pieces, and optimum number of elements in series and parallel connection was derived. As a result of the analysis, it was made clear that the optimum number of thermoelectric module arrays in series and parallel connection varies depending on insolation intensity. It was found preferable that the number of parallel connection array be set to one to two in a region or time period in which low insolation intensity is distributed in greater amount. In the case where high insolation intensity is distributed in a greater amount, setting it to two to three is preferable. By using the structured design method and the HASP Tokyo data, thermoelectric element modules were interconnected with 35 modules in series and two in parallel on a cooling panel installed on the roof of the Science University of Tokyo. A simulation result revealed that the average temperature difference on the cooled surface in summer is 4.37 degC, and the solar cell utilization rate is 0.67. It is necessary in the future to improve heat dissipation efficiency and area ratio. 1 ref., 12 figs., 5 tabs.

  1. Output characteristic of photovoltaic module on different installing conditions. Comparison with calculated value and measured value; Secchi joken no kotonaru taiyo denchi module no shutsuryoku tokusei. Suchi kaiseki to jissokuchi tono hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, T.; Morita, Y.; Iwawaki, H.; Fujisawa, T.; Tani, T. [Science University of Tokyo, Tokyo (Japan)

    1997-11-25

    The paper studied output characteristics of photovoltaic modules different in installation conditions on the basis of the energy balance state. In the study, an energy balance equation was constructed for insolation intensity, heat losses from PV surface/back, and output, in order to calculate cell temperatures in each installation condition. A comparative study was made between calculated results and measured data obtained on the top of the school building. The results indicated the following: The thickness of thermal boundary layer became approximately 27mm at insolation intensity of 800 W/m{sup 2}, ambient air temperature of 25degC, and wind velocity of 0.5m/s. When widening air gap from 20mm to 40mm, the cell temperature decreased 4degC, and the output increased 1.6%. In the case of installing photovoltaic modules on the roof considering the relation between the air gap in the heat balance state and the thickness of thermal boundary layer, heat from PV back was released outside the air gap if widening the air gap to more than 30-40mm. The type with a heat insulating material on the panel back decreased in output from other types. 5 refs., 7 figs., 4 tabs.

  2. Research on fabrication technology for thin film solar cells for practical use. Research on low-cost fabrication technology for large-area modules (Over-layered TCO on tempered glass for solar cell); Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Daimenseki module no tei cost seizo gijutsu (kyoka class fukugo tomei doden kiban seizo no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on the fabrication technology of over-layered TCO on tempered glass in fiscal 1994. (1) On the fabrication technology of heat-resistant over-layered TCO, thermal deformation of TCO substrates was studied by both experiment and numerical computation. The thermal deformation increased with carrier concentration. As the observation result on change in lattice strain of heated TCO films by high-temperature X-ray diffraction, lattice strain was largely affected by thermal expansion. (2) On development of the low-temperature heat treatment method of TCO films, a technological prospect was obtained for fabrication of low-resistance TCO films by heat treatment without strength deterioration of tempered TCO substrates. (3) On development of cost reduction technology, the large-area CVD equipment was devised on the basis of the inline tempering method which tempers substrate glass by air cooling after formation of SnO2 film as fabrication method of tempered TCO. The TCO substrate tempered by air cooling could endure the drop test of 227g and 1.5m. 5 figs., 1 tab.

  3. Achievement report for fiscal 1998 on area consortium research and development business, 1st year. Area consortium energy research and development (biofuel production by advanced function bioreactor); 1998 nendo chiiki consortium energy bun'ya. Kokino bio reactor ni yoru bio nenryo seisan ni kansuru kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Studies were made to produce ethanol directly from starch and cellulose and to collect biodiesel fuels from waste oil by an enzymatic method. For an increase in the yield of biodiesel fuel production, lipase enzymes were explored and optimum reaction conditions were sought for. Starch decomposition was quick for conversion into the target material in a system with the co-expression of amylase and glucoamylase present on the yeast cell surface layer. There was dramatically rapid progress in the increase of enzymatic activity in the cell, although dependent on cell membrane surface treatment conditions. In the generation of acetaminophen by recombinant cohesive yeasts, highly active and expressive yeasts were automatically fixed in the porous support (intelligent bioreactor) while those deactivated or dead were automatically removed. For the construction of a fuzzy control system for this reaction, basic models were investigated, built on the basis of the enzymatic model of reaction and substance balance. A high-precision structural analysis was conducted for the exploration of secondary structure stabilizing factors in protein and peptide and for the elucidation of correlations between structure and function. (NEDO)

  4. Study of fuel control strategy based on an fuel behavior model for starting conditions; Nenryo kyodo model ni motozuita shidoji no nenryo hosei hosho ni tsuite no kosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Y.; Uchida, M.; Iwano, H.; Oba, H. [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    We have applied a fuel behavior model to a fuel injection system which we call SOFIS (Sophisticated and Optimized Fuel Injection System) so that we get air/fuel ratio control accuracy and good driveability. However the fuel behavior under starting conditions is still not clear. To meet low emission rules and to get better driveability under starting conditions, better air/fuel ratio control is necessary. Now we have understood the ignition timing, injection timing, and injection pulse width required in such conditions. In former days, we analyzed the state of the air/fuel mixture under cold conditions and made a new fuel behavior model which considered fuel loss such as hydrocarbons and dissolution into oil and so on. Al this time, we have applied this idea to starting. We confirm this new model offers improved air/fuel ratio control. 6 refs., 9 figs., 3 tabs.

  5. Development of technology for thin substrate polycrystalline solar cells for practical use. Development of manufacturing technologies for low-cost substrates (low-cost Si substrates); Usugata takessho taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Tei cost kiban seizo gijutsu kaihatsu (usugata takessho kigan seizo gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on manufacturing technologies for low-cost high-quality Si substrates in fiscal 1994. (1) On the 220mm square type electromagnetic casting technology, development of fast stable casting technology was studied using the previously installed 220mm square type electromagnetic casting furnace. As a result, continuous stable casting was achieved at high casting speed up to 3.0mm/min. Any degradation of crystalline quality due to high speed casting was not found. (2) On the 350mm square type electromagnetic casting furnace, oscillation circuit constants were analyzed for design of the power source for No.4 electromagnetic casting furnace. In graphite heating experiment using the 350mm square type water-cooling copper crucible heated by 1000kW high-frequency power source, sufficient heat quantity was obtained for initial melting of Si. Any problems in Si melting were not found through Al block melting test. 6 figs.

  6. Achievement report for fiscal 1997 on the development of technologies for utilizing biological resources such as complex biosystems. Development of technologies for producing substitute fuel for petroleum by utilizing organisms; 1997 nendo fukugo seibutsukei nado seibutsu shigen riyo gijutsu kaihatsu seika hokokusho. Seibutsu riyo sekiyu daitai nenryo seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Technologies of producing useful substances using the substance decomposing/producing functions of complex biosystems and methods of their handling are developed. In the utilization of microbes in the digestive tracts of termites and longicorns, it is made clear that several kinds of termites cleave the {beta}-O-4 ether linkage. In relation to technologies for wood decomposing complex microbial system construction and complex vector system development, a screening system is constructed in which strains that exhibit complex actions are combined. Concerning the advanced utilization of tropical oil plants, conditions are determined for inducing callus out of oil palm tissues. Out of oil palm sarcocarp tissues, mRNA (messenger ribonucleic acid) is isolated for the construction of a cDNA (complementary deoxyribonucleic acid) library. For the purpose of isolating a powerful promoter, a partial base sequence is determined for ubiquitin that frequently expresses itself in cells. A pathogenic bacterium ailing the oil palm is sampled for identification, and it is inferred that the bacterium is a kind of Ganoderma boninense. (NEDO)

  7. FY 1997 report on the results of the industrial technology R and D project. Development of technology to use biological resources such as the complex biological system (Development of biological use petroleum substitution fuel production technology); 1997 nendo fukugo seibutsukei nado seibutsu shigen riyo gijutsu kaihatsu seika hokokusho. Seibutsu riyo sekiyu daitai nenryo seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Experimental researches were conducted and the FY 1997 results were reported with the aim of establishing analytical technology for the complex biological system by which the complex biological system can be analyzed in such a state as it is using the molecular biological method. In the study of the molecular genetic analytical technology, PCR primers used for amplification of topoisomerase II genes of the whole eukaryote was designed. As to the histochemical analytical technology, a study was made on the new constitution microorganism detection method by the hybridization method and the antibody specific dyeing method, and the following were conducted: manifestation in quantity of colibacillus and the recovery, refining, and construction of peptide library by fuzzy display method. Concerning the functional analytical technology, technological researches were made such as the environmental adaptation mechanism of high thermophile and the information transfer mechanism among bacteria through cell membranes for elucidation of the special environment detection/response mechanism and the special environment adaptation/resistance mechanism. As to the separation/culture technology, various anaerobic microorganisms were separated from marine sponge for the development of a method of culturing in 3D matrices. (NEDO)

  8. Improvement of the efficiency characteristics on the photovoltaic generation system based on a generation control circuit. Part 3. Research on architectural systematization of energy conversion devices; Dosaten seigyo kairo wo mochiita taiyo denchi hatsuden koritsu no kaizen. 3. Energy henkan no kenchiku system ka ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, T.; Ito, N.; Kimura, G.; Fukao, S.; Sunaga, N.; Tsunoda, M.; Muro, K. [Tokyo Metropolitan University, Tokyo (Japan)

    1996-10-27

    In introducing a photovoltaic power generation system to urban homes, the general practice is to install a large number of solar cell panels on the roof. However, as is often the case, a part of the solar cell panels is in the shadows (partial shadows) of neighboring homes, electric poles, cables and trees. Under the circumstances, studies were made on the numerous changes in the lowered generating capacity of individual solar cells by the partial shadows. Developed by the authors were the generation point control principle, in which the generation point was individually controlled on serially connected plural solar cell modules, and a practical circuit system based on that principle with the effects verified in a field test. In the test, the generated power of the system was 476W without partial shadows, and was 323W with partial shadows and without the operation of the generation point control circuit, increasing to 406W with partial shadows and with the operation of the circuit. As a result, compared with the case where no generation point control circuit was employed, the effectiveness of the proposed circuit was evident. 3 refs., 10 figs., 1 tab.

  9. Change of environmental factors in different site which effect the conversion efficiency of photovoltaic module. Comparison of the environmental factors in Shinjuku Tokyo with the one in Chino Nagano; Kotonaru chiten ni okeru taiyo denchi no henkan koritsu ni eikyo wo ataeru kankyo inshi no henka. Tokyoto Shinjukuku to Naganoken Chinoshi no kankyo inshi no hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Higuchi, T.; Tani, T.; Hirata, Y.; Inasaka, T. [Science University of Tokyo, Tokyo (Japan)

    1997-11-25

    Environmental factors affecting conversion efficiency of solar cells were measured in Tokyo and Nagano to comparatively study the difference. In the study, measurement was made of intensity of global solar radiation on an inclined surface (insolation intensity), ambient air temperature, and distribution of spectral solar radiation at the two points. Also measured were output characteristics of polycrystal silicon solar cell modules and amorphous silicon solar cell modules. The result of the comparative analysis was as follows: The annual inclined global solar radiation amount integrated in 1996 is 27% more in Nagano than in Tokyo. The weighted average insolation intensity in Nagano is 0.09 kW/m{sup 2} higher in Tokyo. The weighted average cell temperature in Nagano is 4degC lower than in Tokyo. The effective spectral ratio in Nagano is 1-2% lower both in polycrystal Si and amorphous Si than in Tokyo. Thus, it was inferred from that environmental factors are different that conversion efficiencies of photovoltaic modules were different. 6 refs., 5 figs., 5 tabs.

  10. Method for estimation of the output electric power of PV module with considering environmental factors. Method for estimation of output using I-V curves; Kankyo inshi wo koryoshita taiyo denchi module no shutsuryoku keisanho. I-V tokusei curve ni yoru keisan

    Energy Technology Data Exchange (ETDEWEB)

    Yamagami, Y.; Tani, T. [Science University of Tokyo, Tokyo (Japan)

    1996-10-27

    Based on the basic quality equation of photovoltaic (PV) cell, a quality equation of PV module has been constructed by considering the spectral distribution of solar radiation and its intensity. A calculation method has been also proposed for determining the output from current-voltage (I-V) curves. Effectiveness of this method was examined by comparing calculated results and observed results. Amorphous Si (a-Si) and polycrystal Si PV modules were examined. By considering the environmental factors, differences of the annual output between the calculated and observed values were reduced from 2.50% to 0.95% for the a-Si PV module, and from 2.52% to 1.24% for the polycrystal Si PV module, which resulted in the reduction more than 50%. For the a-Si PV module, the environmental factor most greatly affecting the annual output was the spectral distribution of solar radiation, which was 3.86 times as large as the cell temperature, and 1.04 times as large as the intensity of solar radiation. For the polycrystal PV module, the environmental factor most greatly affecting the annual output was the cell temperature, which was 7.05 times as large as the spectral distribution of solar radiation, and 1.74 times as large as the intensity of solar radiation. 6 refs., 4 figs., 1 tab.

  11. Change of photovoltaic module conversion efficiency with the environmental factors in different site. Comparison of the conversion efficiency in Tokyo with the one in Nagano; Kotonaru chiten ni okeru taiyo denchi module no shutsuryoku tokusei no henka. Tokyoto Shinjukuku to Naganoken Chinoshi tono hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Higuchi, T.; Tani, T.; Hirata, Y.; Inasaka, T. [Science University of Tokyo, Tokyo (Japan)

    1997-11-25

    Assuming that photovoltaic power systems were installed at two points, Shinjuku Tokyo and Chino Nagano, a study was conducted of difference in generated output of the systems caused by the difference in environmental factors. In the study, it was assumed that two of the photovoltaic power system with rated capacity of 3kW were installed at the two points, and the annual generated output was calculated and compared by the conventional method considering only cell temperature and the output estimation method considering intensity of solar radiation, cell temperature, and spectral distribution of solar radiation. The result of the study was as follows: the difference in output ratio at the two points was 1.7% or lower under the influence of intensity of solar radiation and cell temperature. On the other hand, under the influence of the distribution of spectral solar radiation, the difference is larger than under other environmental factors, 2.4% in polycrystalline Si and 5.5% in amorphous Si. The generated output estimated by the conventional method and the spectral method produced a difference between 81 kWh in Tokyo and 258 kWh in Nagano in amorphous Si. This is because environmental factors such as intensity of solar radiation and distribution of spectral solar radiation are different between the two points. 1 ref., 2 figs., 3 tabs.

  12. Evaluation of PV modules integrated with roofing materials; Kenzai ittaigata taiyo denchi module no hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Morizane, M.; Yagiura, T.; Nakashima, S.; Yagi, H.; Murata, K.; Uchihashi, K.; Tsuda, S.; Nakano, S. [Sanyo Electric Co. Ltd., Osaka (Japan); Ito, M.; Kurimoto, T.; Yamakawa, H.; Fujiwara, T. [Kubota Corp., Osaka (Japan)

    1997-11-25

    PV modules unified with building materials which are low in cost, easy to install and excellent in designing were developed and were evaluated in various tests. As to the basic structure of this module, seamless and unified construction with the back metal plate was adopted considering improvement in fire prevention and cost reduction. About the installation, module is easy to install by just fit connection with the frame, and easy to remove with no use of special tools. Concerning intensity and durability requested for this module, tests on reliability such as torsion strength and wind pressure resistance were conducted according to JIS standards, and it was confirmed that there were no problems. Also on the long-term durability, tests on long-term reliability were carried out by doubling test terms of the temperature/humidity cycle test, salt water resistance test, etc., and the reliability the same as that of the existing type was confirmed. In the verification test using a model house, no changes were seen in electrical characteristics and appearance, and waterproof was also favorable one and a half year after the installation. 4 refs., 7 figs., 5 tabs.

  13. Stem Cells

    Science.gov (United States)

    Stem cells are cells with the potential to develop into many different types of cells in the body. They serve as a repair ... body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  14. Upgrading of brown coal by slurry-dewatering; Kattan no yuchu dassui ni yoru clean kotai nenryo no seizo

    Energy Technology Data Exchange (ETDEWEB)

    Okuma, O.; Shimizu, T.; Inoue, T.; Shigehisa, T.; Deguchi, T.; Katsushima, S. [Kobe Steel, Ltd., Kobe (Japan)

    1996-10-28

    This paper describes an outline of solid fuel production process from brown coal and the investigation results of its elemental techniques. Dried coal is produced by this process which consists of a dewatering of crushed brown coal in oil-based solvent, a solid and liquid separation of slurry, and a remained oil recovery by heating. This process is characterized by the higher thermal efficiency compared with usual drying and the restraint of spontaneous combustion of product coal. It was revealed that solid fuel with low moisture, low ash, low sulfur, and suppressed spontaneous combustion property can be produced from Australian brown coal through this process. From the comparison between kerosene and fuel oil A, it was confirmed that the oil content during dewatering was smaller and the oil recovery by heating was easier by using a solvent with lower boiling point. It was also confirmed that the spontaneous combustion property can be suppressed using small amount of asphalt by solving asphalt in the solvent and adsorbing asphalt on the surface of brown coal. From these results, low rank coals including brown coal, which are difficult to use, are expected to be used as clean coal with low ash and low sulfur through this process. 2 refs., 7 figs., 2 tabs.

  15. Analysis of fuel spray characteristics for premixed lean diesel combustion; Kihaku yokongo diesel kikan ni okeru nenryo funmu kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, S.; Harada, a.; Miyamoto, T.; Akagawa, H.; Tsujimura, K.

    1997-10-01

    Premixed lean diesel combustion (PREDIC) makes it possible to achieve low NOx emission. It is an important factor to make the homogeneous spray formation for PREDIC. In this paper presents I the effect of the spray dispersion on emission characteristic were analyzed with the spray observation and engine test. Pintle type nozzle, which has different feature from orifice type nozzle, are used to form the hollow cone spray. As a result, the pintle type nozzle having grooves to generate the swirl flow, makes the reduced penetration in comparison with the hole nozzle under low ambient gas pressure. And it could improve THC, CO emissions at low NOx emission condition. 7 refs., 12 figs., 1 tab.

  16. Cell-cell channels

    National Research Council Canada - National Science Library

    Baluška, F; Volkmann, Dieter; Barlow, P. W

    2006-01-01

    ...-Negative Bacteria Pheromone-Responsive Conjugative Plasmids in E. faecalis Nonpheromone-Responsive Plasmids in G+ Bacteria 21 22 27 28 Section II: Ciliate Cells 3. The Tetrahymena Conjugation Ju...

  17. Fuel cells

    Science.gov (United States)

    Hooie, D. T.; Harrington, B. C., III; Mayfield, M. J.; Parsons, E. L.

    1992-07-01

    The primary objective of DOE's Fossil Energy Fuel Cell program is to fund the development of key fuel cell technologies in a manner that maximizes private sector participation and in a way that will give contractors the opportunity for a competitive posture, early market entry, and long-term market growth. This summary includes an overview of the Fuel Cell program, an elementary explanation of how fuel cells operate, and a synopsis of the three major fuel cell technologies sponsored by the DOE/Fossil Energy Phosphoric Acid Fuel Cell program, the Molten Carbonate Fuel Cell program, and the Solid Oxide Fuel Cell program.

  18. Polymer electric battery to challenge light weight of portable machines; Keitai kiki no keiryoka ni idomu porima denchi

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Masayuki.

    1999-06-01

    Polymer electric battery is one of lithium secondary battery, roughly divided into two types. One type is to use the Li ion active polymer as electrode active matter and polyaniline was used as a positive electrode in a part of the coin type secondary battery. Recently, organic sulfur polymer has been paid attention as the positive electrode materials with high energy density, an example of a larger capacity by compounding sulfur was reported and its further development was expected. Another type of polymer electric battery is to use solid polyelectrolyte (SPE) into separators and binders of batteries. Polymer electric battery had a character to be packaged by the soft aluminum minute film since the shape solidified from polymer at the interior was independent on a case. (NEDO)

  19. Influence of angle of inclination on power of solar module; Taiyo denchi module no keisha kakudo to shutsuryoku tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Tsutsumi, K.; Nishitani, M. [Dai Ichi University, College of Technology, Kagoshima (Japan)

    1997-11-25

    Experiment/study were conducted on the influence of angle of inclination on output of solar modules. In the experiment, changing the angle of inclination of the photovoltaic module installed on the top of school building to 0, 30, 60 and 90 degC, the global radiation on an inclined surface was measured by pyranometer equipped with the module, and at the same time output characteristics were measured by I-V curve tracer. In the I-V curve tracer, voltage, current, and output capability diagram are illustrated automatically changing bias voltage to get the maximum output. The global radiation on an inclined surface and the maximum output indicated an almost proportional relation and were expressed in a recursion method. Moreover, measurement of the global radiation is usually conducted using the amount of global radiation on a horizontal surface, and the global radiation on an inclined surface is calculated as a sum of the direct solar radiation amount and the sky solar radiation amount after determining a penetration rate by the relational equation. By calculating the global radiation on an inclined surface, it becomes possible to calculate the maximum output of photovoltaic modules by this recursion method. 1 ref., 6 figs., 1 tab.

  20. Cell Motility

    CERN Document Server

    Lenz, Peter

    2008-01-01

    Cell motility is a fascinating example of cell behavior which is fundamentally important to a number of biological and pathological processes. It is based on a complex self-organized mechano-chemical machine consisting of cytoskeletal filaments and molecular motors. In general, the cytoskeleton is responsible for the movement of the entire cell and for movements within the cell. The main challenge in the field of cell motility is to develop a complete physical description on how and why cells move. For this purpose new ways of modeling the properties of biological cells have to be found. This long term goal can only be achieved if new experimental techniques are developed to extract physical information from these living systems and if theoretical models are found which bridge the gap between molecular and mesoscopic length scales. Cell Motility gives an authoritative overview of the fundamental biological facts, theoretical models, and current experimental developments in this fascinating area.

  1. Photovoltaic Cells

    Directory of Open Access Journals (Sweden)

    Karolis Kiela

    2012-04-01

    Full Text Available The article deals with an overview of photovoltaic cells that are currently manufactured and those being developed, including one or several p-n junction, organic and dye-sensitized cells using quantum dots. The paper describes the advantages and disadvantages of various photovoltaic cells, identifies the main parameters, explains the main reasons for the losses that may occur in photovoltaic cells and looks at the ways to minimize them.Article in Lithuanian

  2. Electrochemical Cell

    DEFF Research Database (Denmark)

    1999-01-01

    The invention relates to a rechargeable electrochemical cell comprising a negative electrode, an electrolyte and a positive electrode in which the positive electrode structure comprises a lithium cobalt manganese oxide of the composition Li¿2?Co¿y?Mn¿2-y?O¿4? where 0 ... for capacity losses in lithium ion cells and lithium-alloy cells....

  3. Types of Stem Cells

    Science.gov (United States)

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... stem cells blog from the International Society for Stem Cell Research. Learn About Stem Cells From Lab to You ...

  4. Cell suicide

    International Nuclear Information System (INIS)

    May, E.; Coffigny, H.

    2000-01-01

    In the fight of the cell against the damages caused to its DNA by genotoxic agents and specially by ionizing radiations, the p53 protein plays a central part. It intervenes in the proliferation control and the differentiation but also in the keeping of genome integrity. It can direct the damages cells toward suicide, or apoptosis, to avoid the risk of tumor appearance that would be fatal to the whole organism. That is by the disordered state of cells suicide programs that the tumor cells are going to develop. The knowledge of apoptosis mechanisms, to eventually start them on demand, rises up broad hopes in the cancer therapy. (N.C.)

  5. Fuel Cells

    DEFF Research Database (Denmark)

    Smith, Anders; Pedersen, Allan Schrøder

    2014-01-01

    Fuel cells have been the subject of intense research and development efforts for the past decades. Even so, the technology has not had its commercial breakthrough yet. This entry gives an overview of the technological challenges and status of fuel cells and discusses the most promising applications...

  6. Fuel Cells

    Science.gov (United States)

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  7. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    '. This paper is about tech-noscience, and about the proliferation of connections and interdependencies created by it.More specifically, the paper is about stem cells. Biotechnology in general has the power to capture the imagination. Within the field of biotechnology nothing seems more provocative...... and tantalizing than stem cells, in research, in medicine, or as products....

  8. Solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Tsukamoto, Moriaki; Hayashibara, Mitsuo

    1988-08-18

    Concerning the exsisting solar cell utilizing wavelength transition, the area of the solar cell element necessary for unit electric power output can be made small, but transition efficiency of the solar cell as a whole including a plastic plate with phosphor is not high. This invention concerns a solar cell which is appropriate for transferring the light within a wide spectrum range of the sunlight to electricilty efficiently, utilizes wavelength transition and has high efficiency per unit area. In other words, the solar cell of this invention has the feature of providing in parallel with a photoelectric transfer layer a layer of wavelength transitioning material (phosphor) which absorbs the light within the range of wavelength of low photoelectric transfer efficiency at the photoelectric transfer layer and emits the light within the range of wavelength in which the photoelectric transfer rate is high on the light incident side of the photoelectric transfer layer. (5 figs)

  9. Bi-Cell Unit for Fuel Cell.

    Science.gov (United States)

    The patent concerns a bi-cell unit for a fuel cell . The bi-cell unit is comprised of two electrode packs. Each of the electrode packs includes an...invention relates in general to a bi-cell unit for a fuel cell and in particular, to a bi-cell unit for a hydrazine-air fuel cell .

  10. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  11. Electrochemical cell

    Science.gov (United States)

    Redey, L.I.; Myles, K.M.; Vissers, D.R.; Prakash, J.

    1996-07-02

    An electrochemical cell is described with a positive electrode having an electrochemically active layer of at least one transition metal chloride. A negative electrode of an alkali metal and a compatible electrolyte including an alkali metal salt molten at cell operating temperature is included in the cell. The electrolyte is present at least partially as a corrugated {beta}{double_prime} alumina tube surrounding the negative electrode interior to the positive electrode. The ratio of the volume of liquid electrolyte to the volume of the positive electrode is in the range of from about 0.1 to about 3. A plurality of stacked electrochemical cells is disclosed each having a positive electrode, a negative electrode of an alkali metal molten at cell operating temperature, and a compatible electrolyte. The electrolyte is at least partially present as a corrugated {beta}{double_prime} alumina sheet separating the negative electrode and interior to the positive electrodes. The alkali metal is retained in a porous electrically conductive ceramic, and seals for sealing the junctures of the electrolyte and the adjacent electrodes at the peripheries thereof. 8 figs.

  12. FY 1998 annual report on the conversion of fuel at Igumnovskaya thermal power plant; Igumnovskaya hatsudensho nenryo tenkan 1998 nendo chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    As part of the industrially advanced countries' joint action on the basis of the United Nations Framework Convention on Climate Change (UNFCCC), a thermal power plant in Igumnovskaya (I-plant), Russia was selected as the candidate for rationalization by conversion of fuel from coal to natural gas and introduction of combined-cycle generation, for investigation of the effect on reduction of greenhouse gas generation. The I-plant is located in one of the Russia's largest chemical industry regions, supplying power and steam to the factories in the region. The draft rationalization plan adopts a combination of a coal-fired 300,000 kWh plant that has not been completed and obsolete facilities in the I-plant as the reference case. The plan is drafted to construct a 450,000 kWh combined cycle unit and 3-200 t/h boilers, while effectively utilizing the existing facilities. It requires an investment of US$340 million. The construction works are scheduled to start in 2002 for the initial start-up in 2004. It is expected to reduce CO2 emissions by 1.8 million tons a year and cumulatively 52.7 million tons in the 30-year period from 2005. (NEDO)

  13. Improvement of lean combustion characteristics of heavy-hydrocarbon fuels with hydrogen addition; Suiso tenka ni yoru kokyu tanka suisokei nenryo no kihaku nensho no kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Y. [Saitama Institute of Technology, Saitama (Japan); Ishizuka, S. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

    1999-09-25

    The Lewis numbers of lean heavy-hydrocarbon fuels are larger than unity, and hence, their flames are prone to extinction in a shear flow, which occurs in a turbulent combustion. Here, propane is used as a representative fuel of heavy-hydrocarbon fuels because the Lewis number of lean propane/air mixtures is larger than unity, and an attempt to improve its combustion characteristics by hydrogen addition has been made. A tubular flame burner is used to evaluate its improvement, since a rotating, stretched vortex flow is established in the burner. The results show that with' hydrogen addition, the fuel concentration, the flame diameter and the flame temperature at extinction are reduced and its combustion characteristics are improved. However, it is found that the effective equivalence ration at extinction cannot become so small as that of lean methane/air mixture, which has a Lewis number less than unity. (author)

  14. Numerical simulation of fuel sprays and combustion in a premixed lean diesel engine; Kihaku yokongo diesel kikan ni okeru nenryo funmu to nensho no suchi simulation

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, T.; Harada, A.; Sasaki, S.; Shimazaki, N.; Hashizume, T.; Akagawa, H.; Tsujimura, K.

    1997-10-01

    Fuel sprays and combustion in a direct injection Premixed lean Diesel Combustion (PREDIC) engine, which can make smokeless combustion with little NOx emission, is studied numerically. Numerical simulation was carried out by means of KIVA II based computer code with a combustion submodel. The combustion submodel describes the formation of combustible fuel vapor by turbulent mixing and four-step chemical reaction which includes low temperature oxidation. Comparison between computation and experiment shows qualitatively good agreement in terms of heat release rate and NO emission. Computational results indicate that the combustion is significantly influenced by fuel spray characteristics and injection timing to vary NO emission. 10 refs., 8 figs., 1 tab.

  15. Effects of fuel and air mixing on WOT output in direct injection gasoline engine; Chokufun gasoline kikan ni okeru nenryo to kuki no kongo to shutsuryoku seino

    Energy Technology Data Exchange (ETDEWEB)

    Noda, T.; Iriya, Y.; Naito, K.; Mitsumoto, H.; Iiyama, A. [Nissan Motor Co. Ltd., Tokyo (Japan)

    1997-10-01

    The effects of in-cylinder charge motion and the characteristics of the fuel spray and piston crown shape on WOT output in a direct injection gasoline engine are investigated. The fuel and air mixing process in a cylinder is analyzed by computer simulation and LIF method visualization. As a result, the technical factors to achieve enough mixing in a DI gasoline engine equipped with bowl in piston optimized for stratified combustion are clarified. 7 refs., 9 figs., 1 tab.

  16. Effect of fuel composition on poly aromatic hydrocarbons in particulate matter from DI diesel engine; Particulate chu no PAH ni oyobosu nenryo sosei no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, S.; Tatani, T.; Yoshida, H.; Takizawa, H.; Miyoshi, K.; Ikebe, H. [COSMO Research Institute, Tokyo (Japan)

    1997-10-01

    The effect of fuel composition on poly aromatic hydrocarbons (PAH) in particulate matter from DI diesel engine was investigated by using deeply desulfurized fuel and model fuel which properties are not interrelated. It was found that the deeply desulfurized fuel have effect on reducing PAH emissions. Furthermore, it was suggested that poly aromatics in the fuel affect PAH emissions and the influence of tri-aromatics in the fuel was promoted by the coexistence of mono-aromatics or naphthene. PAH formation scheme from each fuel component was proposed by chemical thermodynamic data. 4 refs., 8 figs., 3 tabs.

  17. Historical review of the progress in direct coal liquefaction technology in the 21st century; Sekita kara ekitai nenryo wo tsukuru (chokusetsu ekika)

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, R. [Hokkaido National Industrial Research Institute, Hokkaido (Japan)

    2000-05-20

    Direct coal liquefaction technology under high pressure and temperature was established by Friedrich Bergius in Germany in 1913. Then, Matthias Pier, I.G. Farbenindustrie, realized the industrial production of gasoline from brown coal based on Bergius method in 1927. During World War 2, the industrial production of gasoline from coals was carried out in Germany, the U.K. and Japan. After World War 2, the U.S. Bureau of Mines evaluated the IG process economically. As a result, it was clarified that a coproduction of coal chemicals with gasoline turned to economic advantages for coal liquefaction process. The coproduction of coal chemicals from coal liquefaction process was examined in Japan during 1956-1962. On occurring of the first oil crisis in 1973, a variety of modern coal liquefaction processes, such as SRC process, EDS process, H-Coal process, new IG process and LSE process, were developed in the U.S., Germany and the U.K.. In Japan, the Sunshine Program under AIST, MITI was started in 1974. Under the Sunshine Program, NEDO promoted the development of coal liquefaction technology, Regarding BCL process for the liquefaction of brown coal, the operation of 50 t/d pilot plant was begun from 1988 and continued by 1990 in Victoria, Australia. As to NEDOL initiated from 1996 and continued by 1998 at Kashima, Ibaraki. Results of both process development unit for the upgrading of coal liquids is under construction at Funakawa, Akita to complete coal liquefaction technologies in Japan. Coal liquefaction technologies being developed in Japan are expected to be commercialized in China or Indonesia in the near future. (author)

  18. Study of recent fuel oil cost in air lines (Part 2). Saikin no airline no nenyuhi ni kansuru ichikosatsu (2); Nenryo shohi to hiyo tai koka

    Energy Technology Data Exchange (ETDEWEB)

    Tanabe, Yoshikazu.

    1989-03-01

    Through an arrangement of published data about American air lines during 1985 through 1987, the overall expense vs. transportation fee (expense vs. effect) was studied as a main viewpoint. As a result, the fuel oil cost, even in case of wide fuselage plane, high in transportation efficiency, was high in ratio, 32 to 52% (3 to 5 times as high as that 12 to 14 years ago), and fluctuated connectedly with the oil price. While the jet fuel price fluctuated connectedly with the oil price per equal volume with 1.3 to 1.4 of price ratio. Further, the flight range ratio was recorded to be approx. 0.06 to 0.24 km/kg. While the transportation efficiency was lower than approx. 5000kg*km/kg with a wide range of overall expense, approx. 9 to 87 cents per compensative transportation ton*km. Because even a sudden decrease in transportation quantity did not decrease the overall expense, it was known to be important in management to secure the transportation quantity. 30 refs., 15 figs., 1 tab.

  19. Electrochemical cell

    Science.gov (United States)

    Kaun, T.D.

    An improved secondary electrochemical cell is disclosed having a negative electrode of lithium aluminum, a positive electrode of iron sulfide, a molten electrolyte of lithium chloride and potassium chloride, and the combination that the fully charged theoretical capacity of the negative electrode is in the range of 0.5 to 1.0 that of the positive electrode. The cell thus is negative electrode limiting during discharge cycling. Preferably, the negative electrode contains therein, in the approximate range of 1 to 10 volume % of the electrode, an additive from the materials of graphitized carbon, aluminum-iron alloy, and/or magnesium oxide.

  20. Solar cells

    International Nuclear Information System (INIS)

    1980-01-01

    A method of producing solar cells is described which consists of producing a substantially monocrystalline tubular body of silicon or other suitable semiconductor material, treating this body to form an annular rectifying junction and then cutting it longitudinally to form a number of nearly flat ribbons from which the solar cells are fabricated. The P=N rectifying junction produced by the formation of silicon dioxide on the layers at the inner and outer surfaces of the body can be formed by ion-implantation or diffusion. (U.K.)

  1. Tuning Collective Cell Migration by Cell-Cell Junction Regulation

    NARCIS (Netherlands)

    Friedl, P.; Mayor, R.

    2017-01-01

    Collective cell migration critically depends on cell-cell interactions coupled to a dynamic actin cytoskeleton. Important cell-cell adhesion receptor systems implicated in controlling collective movements include cadherins, immunoglobulin superfamily members (L1CAM, NCAM, ALCAM), Ephrin/Eph

  2. Energy storage cells

    Energy Technology Data Exchange (ETDEWEB)

    Gulia, N.V.

    1980-01-01

    The book deals with the characteristics and potentialities of energy storage cells of various types. Attention is given to electrical energy storage cells (electrochemical, electrostatic, and electrodynamic cells), mechanical energy storage cells (mechanical flywheel storage cells), and hybrid storage systems.

  3. Squamous Cell Carcinoma

    Science.gov (United States)

    ... Kids’ zone Video library Find a dermatologist Squamous cell carcinoma Overview Squamous cell carcinoma: This man's skin ... a squamous cell carcinoma on his face. Squamous cell carcinoma: Overview Squamous cell carcinoma (SCC) is a ...

  4. Learn About Stem Cells

    Science.gov (United States)

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... ISSCR Get Involved Media © 2015 International Society for Stem Cell Research Terms of Use Disclaimer Privacy Policy

  5. Electrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.H.; Kubala, D.M.; Bennett, R.J.

    1977-01-13

    The high energy densities of primary cells on the basis of lithium or sodium as anode material, liquid cathode materials and nonaqueous electrolytes could not previously be fully utilised, because volume changes appearing during the discharge process inside the cell lead to an increase of cell impedance. In order to overcome this disadvantage, according to the invention a tube consisting of carbon which is slotted in the longitudinal direction is used as the cathode current collector. It is elastic in the radial direction and exerts an even pressure in the beaker-shaped cell vessel on the separator and therefore on the anode material touching the inner wall of the vessel. In order to achieve the elastic deformability of the cathode current collector, acetylene soot is used, to which are added as described in the invention, elastomers and/or mixed polymers in quantities of 10 to 30% by weight. Further claims concern the use of at least one oxyhalide of an element of groups V or VI or a halide of an element of groups IV, V or VI of the periodic table in the cathode solution.

  6. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  7. Fuel cells:

    DEFF Research Database (Denmark)

    Sørensen, Bent

    2013-01-01

    A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil...... and nuclear fuel-based energy technologies....

  8. Stem Cells

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 12; Issue 3. Stem Cells: A Dormant Volcano Within Our Body? Devaveena Dey Annapoorni Rangarajan. General Article Volume 12 Issue 3 March 2007 pp 27-34. Fulltext. Click here to view fulltext PDF. Permanent link:

  9. Photovoltaic cell

    Science.gov (United States)

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  10. Fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Enomoto, Hirofumi.

    1989-05-22

    This invention aims to maintain a long-term operation with stable cell output characteristics by uniformly supplying an electrolyte from the reserver to the matrix layer over the entire matrix layer, and further to prevent the excessive wetting of the catalyst layer by smoothly absorbing the volume change of the electrolyte, caused by the repeated stop/start-up of the fuel cell, within the reserver system. For this purpose, in this invention, an electrolyte transport layer, which connects with an electrolyte reservor formed at the electrode end, is partly formed between the electrode material and the catalyst layer; a catalyst layer, which faces the electrolyte transport layer, has through-holes, which connect to the matrix, dispersely distributed. The electrolyte-transport layer is a thin sheet of a hydrophilic fibers which are non-wovens of such fibers as carbon, silicon carbide, silicon nitride or inorganic oxides. 11 figs.

  11. Tuning Collective Cell Migration by Cell-Cell Junction Regulation.

    Science.gov (United States)

    Friedl, Peter; Mayor, Roberto

    2017-04-03

    Collective cell migration critically depends on cell-cell interactions coupled to a dynamic actin cytoskeleton. Important cell-cell adhesion receptor systems implicated in controlling collective movements include cadherins, immunoglobulin superfamily members (L1CAM, NCAM, ALCAM), Ephrin/Eph receptors, Slit/Robo, connexins and integrins, and an adaptive array of intracellular adapter and signaling proteins. Depending on molecular composition and signaling context, cell-cell junctions adapt their shape and stability, and this gradual junction plasticity enables different types of collective cell movements such as epithelial sheet and cluster migration, branching morphogenesis and sprouting, collective network migration, as well as coordinated individual-cell migration and streaming. Thereby, plasticity of cell-cell junction composition and turnover defines the type of collective movements in epithelial, mesenchymal, neuronal, and immune cells, and defines migration coordination, anchorage, and cell dissociation. We here review cell-cell adhesion systems and their functions in different types of collective cell migration as key regulators of collective plasticity. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  12. Electrorefining cell evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Bronson, M.C.; Thomas, R.L. (ed.)

    1989-04-14

    Operational characteristics of the LANL electrorefining cell, a modified LANL electrorefining cell, and an advanced electrorefining cell (known as the CRAC cell) were determined. Average process yields achieved were: 75% for the LANL cell, 82% for the modified LANL cell, and 86% for the CRAC cell. All product metal from the LANL and modified LANL cells was within foundry specifications. Metal from one run in the CRAC cell exceeded foundry specifications for tantalum. The LANL and modified LANL cells were simple in design and operation, but product separation was more labor intensive than with the CRAC cell. The CRAC cell was more complicated in design but remained relatively simple in operation. A decision analysis concluded that the modified LANL cell was the preferred cell. It was recommended that the modified LANL cell be implemented by the Plutonium Recovery Project at Rocky Flats and that development of the CRAC cell continue. 8 refs., 22 figs., 12 tabs.

  13. Basal Cell Carcinoma

    Science.gov (United States)

    ... Kids’ zone Video library Find a dermatologist Basal cell carcinoma Overview Basal cell carcinoma: This skin cancer ... that has received years of sun exposure. Basal cell carcinoma: Overview Basal cell carcinoma (BCC) is the ...

  14. Stem Cell Basics

    Science.gov (United States)

    ... healthy cells replace damaged cells in adult organisms. Stem cell research is one of the most fascinating areas of ... as with many expanding fields of scientific inquiry, research on stem cells raises scientific questions as rapidly as it generates ...

  15. Sickle cell anemia

    Science.gov (United States)

    Anemia - sickle cell; Hemoglobin SS disease (Hb SS); Sickle cell disease ... Sickle cell anemia is caused by an abnormal type of hemoglobin called hemoglobin S. Hemoglobin is a protein inside red blood cells ...

  16. DNA-cell conjugates

    Science.gov (United States)

    Hsiao, Shih-Chia; Francis, Matthew B.; Bertozzi, Carolyn; Mathies, Richard; Chandra, Ravi; Douglas, Erik; Twite, Amy; Toriello, Nicholas; Onoe, Hiroaki

    2016-05-03

    The present invention provides conjugates of DNA and cells by linking the DNA to a native functional group on the cell surface. The cells can be without cell walls or can have cell walls. The modified cells can be linked to a substrate surface and used in assay or bioreactors.

  17. Potency of Stem Cells

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Potency of Stem Cells. Totipotent Stem Cells (Zygote + first 2 divisions). -Can form placenta, embryo, and any cell of the body. Pluripotent (Embryonic Stem Cells). -Can form any cell of the body but can not form placenta, hence no embryo. Multipotent (Adult stem cells).

  18. Skin Stem Cells in Skin Cell Therapy

    Directory of Open Access Journals (Sweden)

    Mollapour Sisakht

    2015-12-01

    Full Text Available Context Preclinical and clinical research has shown that stem cell therapy is a promising therapeutic option for many diseases. This article describes skin stem cells sources and their therapeutic applications. Evidence Acquisition Compared with conventional methods, cell therapy reduces the surgical burden for patients because it is simple and less time-consuming. Skin cell therapy has been developed for variety of diseases. By isolation of the skin stem cell from the niche, in vitro expansion and transplantation of cells offers a surprising healing capacity profile. Results Stem cells located in skin cells have shown interesting properties such as plasticity, transdifferentiation, and specificity. Mesenchymal cells of the dermis, hypodermis, and other sources are currently being investigated to promote regeneration. Conclusions Because skin stem cells are highly accessible from autologous sources and their immunological profile is unique, they are ideal for therapeutic approaches. Optimization of administrative routes requires more investigation own to the lack of a standard protocol.

  19. NKT Cell Responses to B Cell Lymphoma.

    Science.gov (United States)

    Li, Junxin; Sun, Wenji; Subrahmanyam, Priyanka B; Page, Carly; Younger, Kenisha M; Tiper, Irina V; Frieman, Matthew; Kimball, Amy S; Webb, Tonya J

    2014-06-01

    Natural killer T (NKT) cells are a unique subset of CD1d-restricted T lymphocytes that express characteristics of both T cells and natural killer cells. NKT cells mediate tumor immune-surveillance; however, NKT cells are numerically reduced and functionally impaired in lymphoma patients. Many hematologic malignancies express CD1d molecules and co-stimulatory proteins needed to induce anti-tumor immunity by NKT cells, yet most tumors are poorly immunogenic. In this study, we sought to investigate NKT cell responses to B cell lymphoma. In the presence of exogenous antigen, both mouse and human NKT cell lines produce cytokines following stimulation by B cell lymphoma lines. NKT cell populations were examined ex vivo in mouse models of spontaneous B cell lymphoma, and it was found that during early stages, NKT cell responses were enhanced in lymphoma-bearing animals compared to disease-free animals. In contrast, in lymphoma-bearing animals with splenomegaly and lymphadenopathy, NKT cells were functionally impaired. In a mouse model of blastoid variant mantle cell lymphoma, treatment of tumor-bearing mice with a potent NKT cell agonist, α-galactosylceramide (α-GalCer), resulted in a significant decrease in disease pathology. Ex vivo studies demonstrated that NKT cells from α-GalCer treated mice produced IFN-γ following α-GalCer restimulation, unlike NKT cells from vehicle-control treated mice. These data demonstrate an important role for NKT cells in the immune response to an aggressive hematologic malignancy like mantle cell lymphoma.

  20. Epithelial cell polarity, stem cells and cancer

    DEFF Research Database (Denmark)

    Martin-Belmonte, Fernando; Perez-Moreno, Mirna

    2011-01-01

    After years of extensive scientific discovery much has been learned about the networks that regulate epithelial homeostasis. Loss of expression or functional activity of cell adhesion and cell polarity proteins (including the PAR, crumbs (CRB) and scribble (SCRIB) complexes) is intricately related......, deregulation of adhesion and polarity proteins can cause misoriented cell divisions and increased self-renewal of adult epithelial stem cells. In this Review, we highlight some advances in the understanding of how loss of epithelial cell polarity contributes to tumorigenesis....

  1. Modeling cell-in-cell structure into its biological significance

    OpenAIRE

    He, M-f; Wang, S; Wang, Y; Wang, X-n

    2013-01-01

    Although cell-in-cell structure was noted 100 years ago, the molecular mechanisms of ?entering' and the destination of cell-in-cell remain largely unclear. It takes place among the same type of cells (homotypic cell-in-cell) or different types of cells (heterotypic cell-in-cell). Cell-in-cell formation affects both effector cells and their host cells in multiple aspects, while cell-in-cell death is under more intensive investigation. Given that cell-in-cell has an important role in maintainin...

  2. Sickle Cell Disease

    Science.gov (United States)

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells are shaped like a crescent or sickle. They ... last as long as normal, round red blood cells. This leads to anemia. The sickle cells also ...

  3. Host cell reactivation in mammalian cells

    International Nuclear Information System (INIS)

    Lytle, C.D.; Benane, S.G.; Stafford, J.E.

    1976-01-01

    The survival of UV-irradiated herpes simplex virus was determined in cultured Potoroo (a marsupial) and human cells under lighting conditions which promoted photereactivation. Photoreactivation was readily demonstrated for herpes virus in two lines of Potoroo cells with dose reduction factors of 0.7 to 0.8 for ovary cells and 0.5 to 0.7 for kidney cells. Light from Blacklite (near UV) lamps was more effective than from Daylight (mostly visible) lamps, suggesting that near UV radiation was more effecient for photoreactivation in Potoroo cells. The quantitative and qualitative aspects of this photoreactivation were similar to those reported for a similar virus infecting chick embryo cells. UV-survival curves of herpes virus in Potoroo cells indicated a high level of 'dark' host cell reactivation. No photoreactivation was found for UV-irradiated vaccinia virus in Potoroo cells. A similar photoreactivation study was done using special control lighting (lambda>600 nm) and human cells with normal repair and with cells deficient in excision repair (XP). No photoreactivation was found for UV-irradiated herpes virus in either human cell with either Blacklite or Daylight lamps as the sources of photoreactivating light. This result contrasts with a report of photoreactivation for a herpes virus in the same XP cells using incandescent lamps. (author)

  4. Fuel cell-fuel cell hybrid system

    Science.gov (United States)

    Geisbrecht, Rodney A.; Williams, Mark C.

    2003-09-23

    A device for converting chemical energy to electricity is provided, the device comprising a high temperature fuel cell with the ability for partially oxidizing and completely reforming fuel, and a low temperature fuel cell juxtaposed to said high temperature fuel cell so as to utilize remaining reformed fuel from the high temperature fuel cell. Also provided is a method for producing electricity comprising directing fuel to a first fuel cell, completely oxidizing a first portion of the fuel and partially oxidizing a second portion of the fuel, directing the second fuel portion to a second fuel cell, allowing the first fuel cell to utilize the first portion of the fuel to produce electricity; and allowing the second fuel cell to utilize the second portion of the fuel to produce electricity.

  5. Are mesenchymal stromal cells immune cells?

    NARCIS (Netherlands)

    M.J. Hoogduijn (Martin)

    2015-01-01

    textabstractMesenchymal stromal cells (MSCs) are considered to be promising agents for the treatment of immunological disease. Although originally identified as precursor cells for mesenchymal lineages, in vitro studies have demonstrated that MSCs possess diverse immune regulatory capacities.

  6. Galvanic cells: setting up the Daniell cell.

    OpenAIRE

    Milla González, Miguel

    2008-01-01

    With the reagents (0.05M copper nitrate solution, 0.05M zinc nitrate solution) and material (glassware, potentiometer, electric wire) availabe in the laboratory, the user must set up the Daniell cell. Different configurations can be possible if the half cells are filled with either electrolyte solution. The cell connections to the measuring device can also be changed. In all instances, an explanation of the set up cell is obtained as well as of the measured potential difference.

  7. Inside the Cell

    Science.gov (United States)

    ... NIGMS Home > Science Education > Inside the Cell Inside the Cell Seeing Cells Classroom Poster Order a Free Copy Spotlight The Cell’s Mailroom The Proteasome: The Cell’s Trash Processor in ...

  8. Stem Cell Information: Glossary

    Science.gov (United States)

    ... Long-term self-renewal Meiosis Mesenchymal stem cells Mesoderm Microenvironment Mitosis Multipotent Neural stem cell Neurons Oligodendrocyte ... layers. The three layers are the ectoderm , the mesoderm , and the endoderm . Hematopoietic stem cell - A stem ...

  9. Lung cancer - small cell

    Science.gov (United States)

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  10. [Natural killer cells complot with dendritic cells].

    Science.gov (United States)

    Bielawska-Pohl, Aleksandra; Pajtasz-Piasecka, Elżbieta; Duś, Danuta

    2013-03-18

    Dendritic cells (DC) were initially considered as antigen presenting cells participating in the polarization of the immune response. Further understanding of their biology allowed determining their additional functions such as immunoregulatory and cytotoxicity. Until recently natural killer (NK) cells were known as a homogeneous population of lymphocytes capable of non-specific recognizing and eliminating target cells. Now it is widely accepted that NK cells, as a heterogeneous population, may also possess immunomodulatory functions. Moreover, the most recent analysis of the interactions between DC and NK cells revealed the exceptional functions of these cells. As a result of these studies the existence of bitypic cell population was postulated. The distinguishing features of these hybrid cells are: the expression of surface receptors typical for NK cells and DC, the cytotoxic activity, the production of interferons as well as their ability to present antigen after prior stimulation. Despite the lack of strong direct evidence that the same cell can be both cytotoxic and effectively present the antigen at the same time, there are experimental findings suggesting that generated ex vivo bitypic cells may be used in antitumor therapy. 

  11. NK cells and T cells: mirror images?

    NARCIS (Netherlands)

    Versteeg, R.

    1992-01-01

    The expression of MHC class I molecules protects cells against lysis by natural killer (NK) cells. It is possible that NK cells are 'educated' to recognize self MHC class I molecules and that the combination of self peptide and MHC class I molecule blocks NK-mediated lysis. Here, Rogier Versteeg

  12. Snail modulates cell metabolism in MDCK cells

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Misako, E-mail: haraguci@m3.kufm.kagoshima-u.ac.jp [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Indo, Hiroko P. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Iwasaki, Yasumasa [Health Care Center, Kochi University, Kochi 780-8520 (Japan); Iwashita, Yoichiro [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Fukushige, Tomoko [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Majima, Hideyuki J. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Izumo, Kimiko; Horiuchi, Masahisa [Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Kanekura, Takuro [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Furukawa, Tatsuhiko [Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Ozawa, Masayuki [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan)

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  13. Cell control report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This extensive report provides an essential overview of cells and their use as factory automation building blocks. The following issues are discussed in depth: Cell integration Cell software and standards Future technologies applied to cells Plus Cell control applications including: - rotary parts manufacturing - diesel engine component development - general cell control development at the General Electric Corporation - a vendor list.

  14. GSPEL - Fuel Cell Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Fuel Cell Lab (FCL)Established to investigate, integrate, testand verifyperformance and technology readiness offuel cell systems and fuel reformers for use with...

  15. Squamous cell skin cancer

    Science.gov (United States)

    ... that reflect light more, such as water, sand, concrete, and areas that are painted white. The higher ... - skin - squamous cell; Skin cancer - squamous cell; Nonmelanoma skin cancer - squamous ...

  16. Sony Co., Ltd.: An outlook is made for merchandising of the manganese acid lithium ion battery; Mangansan richiumuion denchi no shohinka ni medo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    Sony Co., Ltd. sells the manganese acid lithium ion battery that a battery is 1 by 2 as to the next generation lithium ion during 99 years. It is characteristics that a price is restrained because manganese is used for the proper pole material instead of cobalt of the rare metal. It becomes mass production by Koriyama factory where a lithium ion battery is being manufactured improving an existent production line. It is seen when some percents of manufacture cost goes down more than cobalt acid battery of news file before. A manganese acid lithium ion battery uses manganese acid lithium for the proper pole of the battery. The efficiency of the charge of the usual lithium ion battery is good, and composition is easy, and uses cobalt acid lithium, which is easy to produce. One side where a material fee is cheap, the stability at the high temperature of manganese acid is low, and composition is difficult. Only NEC Moli Energy corporation who is the subsidiary company of NEC succeeds in the mass production. NEC Moli Energy corporation is extending market share by the price competition power. It seems to have the possibility that manganese acid becomes the main force with a battery by two by new entering of Sony Co., Ltd. of the lithium ion battery extreme big enterprises. (translated by NEDO)

  17. Effect of PV module output power on module temperature; Taiyo denchi no shutsuryoku henka ga module hyomen ondo ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Hongo, T.; Kitamura, A. [Kansai Electric Power Co. Inc., Osaka (Japan); Igaki, K.; Mizumoto, T. [Kanden Kako Co. Inc., Osaka (Japan)

    1996-10-27

    Effect of the photovoltaic (PV) module output power variation on the module surface temperature has been investigated by field measurements. PV modules with capacity of 54 W were used for the temperature measurements. Three 2 kW-class PV systems were operated. T-type thermocouples were used for measuring temperatures. Measurement time intervals were 15 minutes, 30 minutes, 60 minutes, and 24 hours. Measurement period was between May 25, 1995 and June 25, 1996. The surface temperature increased during non-loaded PV output, and decreased during load-carrying PV output. Difference of the surface temperature between non-loaded PV output and load-carrying PV output was 3.5{degree}C at maximum through a year. The surface temperature was saturated within 30 minutes. When PV output was changed in 30 or 60 minutes interval, the variation of surface temperature was distinctly observed. When PV output was changed in 15 minutes interval, it was not observed distinctly. There was no difference of the surface temperatures during the time zones with less solar radiation, such as in the morning and evening, and at night. Except these time zones, difference of the surface temperatures was 3.5{degree}C at maximum. 4 figs.

  18. Study on property-gradient polymer electrolyte for rechargeable lithium batteries; Lithium niji denchi no tame no keisha tokusei kobunshi denkaishitsu no sosei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Kokumi, Z.; Kanemura, S.; Inaba, M.; Takehara, Z.; Yao, K.; Uchimoto, Y. [Kyoto University, Kyoto (Japan)

    1997-02-01

    This paper describes the fundamental experiments for creating property-gradient polymer electrolyte for rechargeable lithium batteries. The rechargeable lithium battery is composed of an anodic composite agent section with high ion conductivity, a separator equivalent section with high mechanical strength (high bridging degree), and a section surpressing the precipitation of metal lithium by contacting with it. The continuous property-gradient polymer electrolyte was tried to be synthesized by means of the plasma polymerization method. As a result, plasma polymerization electrolyte with high ion conductivity could be prepared from the liquid phase by using a monomer with low vapor pressure. Porous material simulating the anodic composite agent was impregnated by the monomer, which was plasma-polymerized. As a result, it was found that the bridging degree decreased from the surface towards the inside of the plasma-polymerized porous material. In addition, polymer was prepared using fluorine-base monomer. Thus, LiF thin film could be prepared through the reaction between the polymer and metal lithium. 3 figs.

  19. Method for estimation of the spectral distribution that influence electric power of PV module; Taiyo denchi shutsuryoku ni eikyo wo ataeru bunko nissha bunpu no suiteiho

    Energy Technology Data Exchange (ETDEWEB)

    Yamagami, Y.; Tani, T. [Science University of Tokyo, Tokyo (Japan)

    1997-11-25

    A method was proposed for estimating the spectral distribution using air mass, precipitable water, and clear indexes which are generally obtainable, and a comparative study was made between the spectral distribution obtained by this method and the measured data using output power of PV modules, etc. as indexes. When solar light comes into the atmosphere, it dissipates receiving scattering/absorption by various gases and aerosols. Direct light component and scattered light component which arrive at the earth surface become functions of air mass and precipitable water. The wavelength distribution of scattered light in cloudy sky is not dependent upon air mass, but affected strongly by absorption band by steam of clouds. By relational equations considered of these, output power and short-circuit current of PV modules are obtained to make a comparison with the measured data. As a result, it was found that this method estimated the spectral distribution with accuracy. Further, seasonal changes in the spectral distribution were well reproduced. The simulation of the module output in Sapporo and Okinawa brought a result that the output in Okinawa is 1.93% larger than in Okinawa. 5 refs., 5 figs., 6 tabs.

  20. Analysis of output characteristics of PV modules under natural sunlight; Shizen taiyokoka ni okeru taiyo denchi module shutsuryoku tokusei no kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Murai, Y.; Igari, S. [Japan Quality Assurance of Organization, Tokyo (Japan)

    1997-11-25

    The paper measured current/voltage characteristics of various PV modules under natural light and analyzed various characteristics such as generated output and module power generation efficiency. In the experiment, installing various PV modules at the solar techno center located at north latitude 34.7deg and east longitude 137.6deg, measurement was made by I-V curve tracer, pyranometer, and thermocouple buried on the module back. As a result, the following were confirmed: As to the monthly mean power generation efficiency, the crystalline system is lowest in summer and highest in winter, and the amorphous system highest in summer and lowest in winter. Concerning the power generation efficiency and illuminance, the gap of power generation efficiency between at high illuminance and at low illuminance is large in the crystalline system and small in amorphous system. Relating to the azimuth angle of module installation and the generated output, the installation inclined 15deg angle west in summer and 15deg angle east in fall/winter generates more power in the crystalline system. On the contrary, the installation on the south face generates more power in the amorphous system. 4 refs., 8 figs., 3 tabs.

  1. The hallmarks of cell-cell fusion.

    Science.gov (United States)

    Hernández, Javier M; Podbilewicz, Benjamin

    2017-12-15

    Cell-cell fusion is essential for fertilization and organ development. Dedicated proteins known as fusogens are responsible for mediating membrane fusion. However, until recently, these proteins either remained unidentified or were poorly understood at the mechanistic level. Here, we review how fusogens surmount multiple energy barriers to mediate cell-cell fusion. We describe how early preparatory steps bring membranes to a distance of ∼10 nm, while fusogens act in the final approach between membranes. The mechanical force exerted by cell fusogens and the accompanying lipidic rearrangements constitute the hallmarks of cell-cell fusion. Finally, we discuss the relationship between viral and eukaryotic fusogens, highlight a classification scheme regrouping a superfamily of fusogens called Fusexins, and propose new questions and avenues of enquiry. © 2017. Published by The Company of Biologists Ltd.

  2. Cell mechanics: a dialogue

    Science.gov (United States)

    Tao, Jiaxiang; Li, Yizeng; Vig, Dhruv K.; Sun, Sean X.

    2017-03-01

    Under the microscope, eukaryotic animal cells can adopt a variety of different shapes and sizes. These cells also move and deform, and the physical mechanisms driving these movements and shape changes are important in fundamental cell biology, tissue mechanics, as well as disease biology. This article reviews some of the basic mechanical concepts in cells, emphasizing continuum mechanics description of cytoskeletal networks and hydrodynamic flows across the cell membrane. We discuss how cells can generate movement and shape changes by controlling mass fluxes at the cell boundary. These mass fluxes can come from polymerization/depolymerization of actin cytoskeleton, as well as osmotic and hydraulic pressure-driven flow of water across the cell membrane. By combining hydraulic pressure control with force balance conditions at the cell surface, we discuss a quantitative mechanism of cell shape and volume control. The broad consequences of this model on cell mechanosensation and tissue mechanics are outlined.

  3. [Exosomes and Immune Cells].

    Science.gov (United States)

    Seo, Naohiro

    2017-05-01

    In addition to the cytokines and cytotoxic granules, exosomes have been known as the intercellular communicator and cytotoxic missile of immune cells for the past decade. It has been well known that mature dendritic cell(DC)-derived exosomes participate in the T cell and natural killer(NK)cell activation, while immature DCs secrete tolerogenic exosomes for regulatory T(Treg)cell generation. Treg cell-derived EVs act as a suppressor against pathogenic type-1 T helper(Th1)cell responses. CD8+ T cells produce tumoricidal exosomes for preventing tumor invasion and metastasis transiently after T cell receptor(TCR)-mediated stimulation. Thus, immune cells produce functional exosomes in the activation state- and/or differentiation stage-dependent manner. In this review, the role of immune cell-derived exosomes will be introduced, focusing mainly on immune reaction against tumor.

  4. Tracking adult stem cells

    NARCIS (Netherlands)

    Snippert, H.J.G.; Clevers, H.

    2011-01-01

    The maintenance of stem-cell-driven tissue homeostasis requires a balance between the generation and loss of cell mass. Adult stem cells have a close relationship with the surrounding tissue--known as their niche--and thus, stem-cell studies should preferably be performed in a physiological context,

  5. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  6. Mammalian cell biology

    International Nuclear Information System (INIS)

    Elkind, M.M.

    1975-01-01

    Progress is reported on the following research projects: the effects of N-ethyl-maleimide and hydroxyurea on hamster cells in culture; sensitization of synchronized human cells to x rays by N-ethylmaleimide; sensitization of hypoxic mammalian cells with a sulfhydryl inhibitor; damage interaction due to ionizing and nonionizing radiation in mammalian cells; DNA damage relative to radioinduced cell killing; spurious photolability of DNA labeled with methyl- 14 C-thymidine; radioinduced malignant transformation of cultured mouse cells; a comparison of properties of uv and near uv light relative to cell function and DNA damage; Monte Carlo simulation of DNA damage and repair mechanisms; and radiobiology of fast neutrons

  7. Molten carbonate fuel cell

    Science.gov (United States)

    Kaun, T.D.; Smith, J.L.

    1986-07-08

    A molten electrolyte fuel cell is disclosed with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas. The cell enclosures collectively provide an enclosure for the array and effectively avoid the problems of electrolyte migration and the previous need for compression of stack components. The fuel cell further includes an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

  8. Mesenchymal Stem Cells

    DEFF Research Database (Denmark)

    Horwood, Nicole J.; Dazzi, Francesco; Zaher, Walid

    2012-01-01

    Mesenchymal stem cells (MSC) are stem cell populations present among the bone marrow stroma and a number of other tissues that are capable of multi-lineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. MSC provide supportive stroma for growth...... and differentiation of hematopoietic stem cells (HSC) and hematopoiesis. These cells have been described as important immunoregulators due to their ability to suppress T cells proliferation. MSC can also directly contribute to tissue repair by migrating to sites of injury and providing a source of cells...

  9. Removable hot cell liners

    International Nuclear Information System (INIS)

    Fitzgibbon, F.J.; Shaffer, D.S.; Ledbetter, J.M.; Wood, W.T.

    1978-01-01

    In 1959 the Los Alamos Scientific Laboratory (LASL) proposed design requirements for an alpha-gamma box system. Among the requirements was a provision for conveniently removing a contaminated cell liner (alpha-gamma box) from an operating cell. Various situations, such as a change in program direction, outmoded equipment, or an unexpected development, could result in a decision to replace a cell liner and reuse the cell for another purpose. The contaminated cell liners could either be stored temporarily for possible future use or disposed of at the LASL contaminated Waste Disposal Area. LASL's experience removing used hot cell liners from operating cells is described

  10. Cell-Based Therapy

    Directory of Open Access Journals (Sweden)

    Masaaki Kitada

    2012-01-01

    Full Text Available Cell transplantation is a strategy with great potential for the treatment of Parkinson's disease, and many types of stem cells, including neural stem cells and embryonic stem cells, are considered candidates for transplantation therapy. Mesenchymal stem cells are a great therapeutic cell source because they are easy accessible and can be expanded from patients or donor mesenchymal tissues without posing serious ethical and technical problems. They have trophic effects for protecting damaged tissues as well as differentiation ability to generate a broad spectrum of cells, including dopamine neurons, which contribute to the replenishment of lost cells in Parkinson's disease. This paper focuses mainly on the potential of mesenchymal stem cells as a therapeutic cell source and discusses their potential clinical application in Parkinson's disease.

  11. NK Cell Exhaustion

    Science.gov (United States)

    Bi, Jiacheng; Tian, Zhigang

    2017-01-01

    Natural killer cells are important effector lymphocytes of the innate immune system, playing critical roles in antitumor and anti-infection host defense. Tumor progression or chronic infections, however, usually leads to exhaustion of NK cells, thus limiting the antitumor/infection potential of NK cells. In many tumors or chronic infections, multiple mechanisms might contribute to the exhaustion of NK cells, such as dysregulated NK cell receptors signaling, as well as suppressive effects by regulatory cells or soluble factors within the microenvironment. Better understanding of the characteristics, as well as the underlying mechanisms of NK cell exhaustion, not only should increase our understanding of the basic biology of NK cells but also could reveal novel NK cell-based antitumor/infection targets. Here, we provide an overview of our current knowledge on NK cell exhaustion in tumors, and in chronic infections. PMID:28702032

  12. Fuel cells seminar

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    This year`s meeting highlights the fact that fuel cells for both stationary and transportation applications have reached the dawn of commercialization. Sales of stationary fuel cells have grown steadily over the past 2 years. Phosphoric acid fuel cell buses have been demonstrated in urban areas. Proton-exchange membrane fuel cells are on the verge of revolutionizing the transportation industry. These activities and many more are discussed during this seminar, which provides a forum for people from the international fuel cell community engaged in a wide spectrum of fuel cell activities. Discussions addressing R&D of fuel cell technologies, manufacturing and marketing of fuel cells, and experiences of fuel cell users took place through oral and poster presentations. For the first time, the seminar included commercial exhibits, further evidence that commercial fuel cell technology has arrived. A total of 205 papers is included in this volume.

  13. Cell fusion of bone marrow cells and somatic cell reprogramming by embryonic stem cells

    OpenAIRE

    Bonde, Sabrina; Pedram, Mehrdad; Stultz, Ryan; Zavazava, Nicholas

    2010-01-01

    Bone marrow transplantation is a curative treatment for many diseases, including leukemia, autoimmune diseases, and a number of immunodeficiencies. Recently, it was claimed that bone marrow cells transdifferentiate, a much desired property as bone marrow cells are abundant and therefore could be used in regenerative medicine to treat incurable chronic diseases. Using a Cre/loxP system, we studied cell fusion after bone marrow transplantation. Fused cells were chiefly Gr-1+, a myeloid cell mar...

  14. Quantitative characterization of cell behaviors through cell cycle progression via automated cell tracking.

    Directory of Open Access Journals (Sweden)

    Yuliang Wang

    Full Text Available Cell behaviors are reflections of intracellular tension dynamics and play important roles in many cellular processes. In this study, temporal variations in cell geometry and cell motion through cell cycle progression were quantitatively characterized via automated cell tracking for MCF-10A non-transformed breast cells, MCF-7 non-invasive breast cancer cells, and MDA-MB-231 highly metastatic breast cancer cells. A new cell segmentation method, which combines the threshold method and our modified edge based active contour method, was applied to optimize cell boundary detection for all cells in the field-of-view. An automated cell-tracking program was implemented to conduct live cell tracking over 40 hours for the three cell lines. The cell boundary and location information was measured and aligned with cell cycle progression with constructed cell lineage trees. Cell behaviors were studied in terms of cell geometry and cell motion. For cell geometry, cell area and cell axis ratio were investigated. For cell motion, instantaneous migration speed, cell motion type, as well as cell motion range were analyzed. We applied a cell-based approach that allows us to examine and compare temporal variations of cell behavior along with cell cycle progression at a single cell level. Cell body geometry along with distribution of peripheral protrusion structures appears to be associated with cell motion features. Migration speed together with motion type and motion ranges are required to distinguish the three cell-lines examined. We found that cells dividing or overlapping vertically are unique features of cell malignancy for both MCF-7 and MDA-MB-231 cells, whereas abrupt changes in cell body geometry and cell motion during mitosis are unique to highly metastatic MDA-MB-231 cells. Taken together, our live cell tracking system serves as an invaluable tool to identify cell behaviors that are unique to malignant and/or highly metastatic breast cancer cells.

  15. Plant stem cell niches.

    Science.gov (United States)

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

  16. Bacterial Cell Wall Components

    Science.gov (United States)

    Ginsberg, Cynthia; Brown, Stephanie; Walker, Suzanne

    Bacterial cell-surface polysaccharides cells are surrounded by a variety of cell-surface structures that allow them to thrive in extreme environments. Components of the cell envelope and extracellular matrix are responsible for providing the cells with structural support, mediating intercellular communication, allowing the cells to move or to adhere to surfaces, protecting the cells from attack by antibiotics or the immune system, and facilitating the uptake of nutrients. Some of the most important cell wall components are polysaccharide structures. This review discusses the occurrence, structure, function, and biosynthesis of the most prevalent bacterial cell surface polysaccharides: peptidoglycan, lipopolysaccharide, arabinogalactan, and lipoarabinomannan, and capsular and extracellular polysaccharides. The roles of these polysaccharides in medicine, both as drug targets and as therapeutic agents, are also described.

  17. What are Stem Cells?

    Directory of Open Access Journals (Sweden)

    Ahmadshah Farhat

    2014-05-01

    Full Text Available   Stem cells are undifferentiated self regenerating multi potential cells. There are three types of stem cells categories by the ability to form after cells and correlated with the body’s development process. Totipotent: these stem cells can form an entire organism such as fertilized egg. Ploripotent: ploripotent cells are those that can form any cell in the body but cannot form an entire organism such as developing embryo’s totipotent cells become ploripotent  Multipotent: Multi potent stem cells are those that can only form specific cells in the body such as blood cells based. Based on the sources of stem cells we have three types of these cells: Autologous: Sources of the patient own cells are (Autologous either the cells from patient own body or his or her cord blood. For this type of transplant the physician now usually collects the periphery rather than morrow because the procedure is easier on like a bane morrow harvest it take place outside of an operating room, and the patient does not to be under general unsetting . Allogenic: Sources of stem cells from another donore are primarily relatives (familial allogenic or completely unrelated donors. Xenogenic: In these stem cells from different species are transplanted e .g striatal porcine fetal mesan cephalic (FVM xenotransplants for Parkinson’s disease. On sites of isolation such as embryo, umbilical cord and other body tissues stem cells are named embnyonic, cord blood, and adult stem cells. The scope of results and clinical application of stem cells are such as: Neurodegenerative conditions (MS,ALS, Parkinson’s, Stroke, Ocular disorders- Glaucoma, retinitis Pigmentosa (RP, Auto Immune Conditions (Lupus, MS,R. arthritis, Diabetes, etc, Viral Conditions (Hepatitis C and AIDS, Heart Disease, Adrenal Disorders, Injury(Nerve, Brain, etc, Anti aging (hair, skin, weight control, overall well being/preventive, Emotional disorders, Organ / Tissue Cancers, Blood cancers, Blood diseases

  18. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    Directory of Open Access Journals (Sweden)

    Quanwen Liu

    2016-01-01

    Full Text Available In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bundles. The hair-cell-like cells exhibited rapid permeation of FM1-43FX. The whole-cell patch-clamp technique was used to measure the membrane currents of cells differentiated for 7 days on chicken utricle stromal cells and analyze the biophysical properties of the hair-cell-like cells by recording membrane properties of cells. The results suggested that the hair-cell-like cells derived from inner ear multipotent cells were functional following differentiation in an enabling environment.

  19. Pluripotent Stem Cells for Schwann Cell Engineering

    NARCIS (Netherlands)

    Ma, Ming-San; Boddeke, Erik; Copray, Sjef

    Tissue engineering of Schwann cells (SCs) can serve a number of purposes, such as in vitro SC-related disease modeling, treatment of peripheral nerve diseases or peripheral nerve injury, and, potentially, treatment of CNS diseases. SCs can be generated from autologous stem cells in vitro by

  20. Regulation of cell polarity by cell adhesion receptors.

    Science.gov (United States)

    Ebnet, Klaus; Kummer, Daniel; Steinbacher, Tim; Singh, Amrita; Nakayama, Masanori; Matis, Maja

    2017-07-22

    The ability of cells to polarize is an intrinsic property of almost all cells and is required for the devlopment of most multicellular organisms. To develop cell polarity, cells integrate various signals derived from intrinsic as well as extrinsic sources. In the recent years, cell-cell adhesion receptors have turned out as important regulators of cellular polarization. By interacting with conserved cell polarity proteins, they regulate the recruitment of polarity complexes to specific sites of cell-cell adhesion. By initiating intracellular signaling cascades at those sites, they trigger their specific subcellular activation. Not surprisingly, cell-cell adhesion receptors regulate diverse aspects of cell polarity, including apico-basal polarity in epithelial and endothelial cells, front-to-rear polarity in collectively migrating cells, and planar cell polarity during organ development. Here, we review the recent developments highlighting the central roles of cell-cell adhesion molecules in the development of cell polarity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Cell cycle control by components of cell anchorage

    OpenAIRE

    Gad, Annica

    2005-01-01

    Extracellular factors, such as growth factors and cell anchorage to the extracellular matrix, control when and where cells may proliferate. This control is abolished when a normal cell transforms into a tumour cell. The control of cell proliferation by cell anchorage was elusive and less well studied than the control by growth factors. Therefore, we aimed to clarify at what points in the cell cycle and through which molecular mechanisms cell anchorage controls cell cycle pro...

  2. The cell cycle as a brake for β-cell regeneration from embryonic stem cells.

    Science.gov (United States)

    El-Badawy, Ahmed; El-Badri, Nagwa

    2016-01-13

    The generation of insulin-producing β cells from stem cells in vitro provides a promising source of cells for cell transplantation therapy in diabetes. However, insulin-producing cells generated from human stem cells show deficiency in many functional characteristics compared with pancreatic β cells. Recent reports have shown molecular ties between the cell cycle and the differentiation mechanism of embryonic stem (ES) cells, assuming that cell fate decisions are controlled by the cell cycle machinery. Both β cells and ES cells possess unique cell cycle machinery yet with significant contrasts. In this review, we compare the cell cycle control mechanisms in both ES cells and β cells, and highlight the fundamental differences between pluripotent cells of embryonic origin and differentiated β cells. Through critical analysis of the differences of the cell cycle between these two cell types, we propose that the cell cycle of ES cells may act as a brake for β-cell regeneration. Based on these differences, we discuss the potential of modulating the cell cycle of ES cells for the large-scale generation of functionally mature β cells in vitro. Further understanding of the factors that modulate the ES cell cycle will lead to new approaches to enhance the production of functional mature insulin-producing cells, and yield a reliable system to generate bona fide β cells in vitro.

  3. Regulatory T cells and B cells: implication on autoimmune diseases

    OpenAIRE

    Wang, Ping; Zheng, Song Guo

    2013-01-01

    The regulatory T (Treg) cells play an important role in the maintenance of homeostasis and the prevention of autoimmune diseases. Although most studies are focusing on the role of Treg cells in T cells and T cells-mediated diseases, these cells also directly affect B cells and other non-T cells. This manuscript updates the role of Treg cells on the B cells and B cell-mediated diseases. In addition, the mechanisms whereby Treg cells suppress B cell responses have been discussed.

  4. Sickle Cell Trait

    Science.gov (United States)

    ... cell trait toolkit » Sickle cell trait fact sheet » SCT and Athletes Some people with SCT have been ... ill. Recommendations on Screening of Student Athletes for SCT Recommendations of the Advisory Committee on Heritable Disorders ...

  5. Antioxidants: Protecting Healthy Cells

    Science.gov (United States)

    ... and Nutrients Antioxidants - Protecting Healthy Cells Print Email Antioxidants - Protecting Healthy Cells Reviewed by Taylor Wolfram, MS, ... to cardiovascular disease and certain types of cancers. Antioxidants — such as vitamins C and E and carotenoids, ...

  6. Fuel cells: Project Volta

    Energy Technology Data Exchange (ETDEWEB)

    Vellone, R.; Di Mario, F.

    1987-09-01

    This paper discusses research and development in the field of fuel cell power plants. Reference is made to the Italian research Project Volta. Problems related to research program financing and fuel cell power plant marketing are discussed.

  7. Border cell release

    DEFF Research Database (Denmark)

    Mravec, Jozef

    2017-01-01

    Plant border cells are specialised cells derived from the root cap with roles in the biomechanics of root growth and in forming a barrier against pathogens. The mechanism of highly localised cell separation which is essential for their release to the environment is little understood. Here I present...... in situ analysis of Brachypodium distachyon, a model organism for grasses which possess type II primary cell walls poor in pectin content. Results suggest similarity in spatial dynamics of pectic homogalacturonan during dicot and monocot border cell release. Integration of observations from different...... species leads to the hypothesis that this process most likely does not involve degradation of cell wall material but rather employs unique cell wall structural and compositional means enabling both the rigidity of the root cap as well as detachability of given cells on its surface....

  8. Giant Cell Arteritis

    Science.gov (United States)

    Giant cell arteritis is a disorder that causes inflammation of your arteries, usually in the scalp, neck, and arms. ... arteries, which keeps blood from flowing well. Giant cell arteritis often occurs with another disorder called polymyalgia ...

  9. Fluorescence live cell imaging.

    Science.gov (United States)

    Ettinger, Andreas; Wittmann, Torsten

    2014-01-01

    Fluorescence microscopy of live cells has become an integral part of modern cell biology. Fluorescent protein (FP) tags, live cell dyes, and other methods to fluorescently label proteins of interest provide a range of tools to investigate virtually any cellular process under the microscope. The two main experimental challenges in collecting meaningful live cell microscopy data are to minimize photodamage while retaining a useful signal-to-noise ratio and to provide a suitable environment for cells or tissues to replicate physiological cell dynamics. This chapter aims to give a general overview on microscope design choices critical for fluorescence live cell imaging that apply to most fluorescence microscopy modalities and on environmental control with a focus on mammalian tissue culture cells. In addition, we provide guidance on how to design and evaluate FP constructs by spinning disk confocal microscopy. © 2014 Elsevier Inc. All rights reserved.

  10. FUEL CELL ELECTRODE MATERIALS

    Science.gov (United States)

    FUEL CELL ELECTRODE MATERIALS. RAW MATERIAL SELECTION INFLUENCES POLARIZATION BUT IS NOT A SINGLE CONTROLLING FACTOR. AVAILABLE...DATA INDICATES THAT AN INTERRELATIONSHIP OF POROSITY, AVERAGE PORE VOLUME, AND PERMEABILITY CONTRIBUTES TO ELECTRODE FUEL CELL BEHAVIOR.

  11. Basal cell nevus syndrome

    Science.gov (United States)

    ... nevus syndrome Basal cell nevus syndrome - face References Evans DG, Farndon PA. Nevoid basal cell carcinoma syndrome. ... A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among ...

  12. Merkel Cell Carcinoma

    Science.gov (United States)

    ... H, Shuda M, Chang Y, et al . “Clonal integration of a polyomavirus in human Merkel cell carcinoma.” ... look at it under the microscope. This process continues until the surgeon no longer sees cancer cells. ...

  13. Separators for electrochemical cells

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Steven Allen; Anakor, Ifenna Kingsley; Farrell, Greg Robert

    2018-01-16

    Provided are separators for use in an electrochemical cell comprising (a) an inorganic oxide and (b) an organic polymer, wherein the inorganic oxide comprises organic substituents. Also provided are electrochemical cells comprising such separators.

  14. Dendritic cell vaccines.

    Science.gov (United States)

    Mosca, Paul J; Lyerly, H Kim; Clay, Timothy M; Morse, Michael A; Lyerly, H Kim

    2007-05-01

    Dendritic cells are antigen-presenting cells that have been shown to stimulate tumor antigen-specific T cell responses in preclinical studies. Consequently, there has been intense interest in developing dendritic cell based cancer vaccines. A variety of methods for generating dendritic cells, loading them with tumor antigens, and administering them to patients have been described. In recent years, a number of early phase clinical trials have been performed and have demonstrated the safety and feasibility of dendritic cell immunotherapies. A number of these trials have generated valuable preliminary data regarding the clinical and immunologic response to DC-based immunotherapy. The emphasis of dendritic cell immunotherapy research is increasingly shifting toward the development of strategies to increase the potency of dendritic cell vaccine preparations.

  15. Stem Cell Transplant

    Science.gov (United States)

    ... Graft-versus-host disease: A potential risk when stem cells come from donors If you receive a transplant ... medications and blood products into your body. Collecting stem cells for transplant If a transplant using your own ...

  16. NIA Aging Cell Repository

    Data.gov (United States)

    Federal Laboratory Consortium — To facilitate aging research on cells in culture, the NIA provides support for the NIA Aging Cell Repository, located at the Coriell Institute for Medical Research...

  17. Sickle cell anemia.

    OpenAIRE

    ŘÍHOVÁ, Tereza

    2013-01-01

    This thesis is about the disease called sickle cell anemia, or drepanocytosis. In this thesis is described the history of the disease, pathophysiology, laboratory features, various clinical features, diferencial diagnosis, quality of life in sickle cell anemia and therapy.

  18. Mesenchymal Stem Cells

    DEFF Research Database (Denmark)

    Horwood, Nicole J.; Dazzi, Francesco; Zaher, Walid

    2012-01-01

    and differentiation of hematopoietic stem cells (HSC) and hematopoiesis. These cells have been described as important immunoregulators due to their ability to suppress T cells proliferation. MSC can also directly contribute to tissue repair by migrating to sites of injury and providing a source of cells......Mesenchymal stem cells (MSC) are stem cell populations present among the bone marrow stroma and a number of other tissues that are capable of multi-lineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. MSC provide supportive stroma for growth...... for differentiation and/or providing bystander support for resident stromal cells. This chapter discusses the cellular and molecular properties of MSC, the mechanisms by which they can modulate immune responses and the clinical applications of MSC in disorders such as graft-versus-host disease and aplastic anaemia...

  19. Diagram of Cell to Cell Communication

    Science.gov (United States)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  20. Cell Factory Engineering

    DEFF Research Database (Denmark)

    Davy, Anne Mathilde; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    2017-01-01

    focused on individual strategies or cell types, but collectively they fall under the broad umbrella of a growing field known as cell factory engineering. Here we condense >130 reviews and key studies in the art into a meta-review of cell factory engineering. We identified 33 generic strategies......-review provides general strategy guides for the broad range of applications of rational engineering of cell factories....

  1. Anterior Horn Cell Diseases

    Directory of Open Access Journals (Sweden)

    Merve Firinciogullari

    2016-09-01

    Full Text Available The anterior horn cells control all voluntary movement. Motor activity, respiratory, speech, and swallowing functions are dependent upon signals from the anterior horn cells. Diseases that damage the anterior horn cells, therefore, have a profound impact. Symptoms of anterior horn cell loss (weakness, falling, choking lead patients to seek medical attention. In this article, anterior horn diseases were reviewed, diagnostic criteria and management were discussed in detail. [Archives Medical Review Journal 2016; 25(3.000: 269-303

  2. Skeletal (stromal) stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Kermani, Abbas Jafari; Zaher, Walid

    2015-01-01

    Skeletal (marrow stromal) stem cells (BMSCs) are a group of multipotent cells that reside in the bone marrow stroma and can differentiate into osteoblasts, chondrocytes and adipocytes. Studying signaling pathways that regulate BMSC differentiation into osteoblastic cells is a strategy....../preadipocyte factor 1 (Dlk1/Pref-1), the Wnt co-receptor Lrp5 and intracellular kinases. This article is part of a Special Issue entitled: Stem Cells and Bone....

  3. Red blood cell production

    Science.gov (United States)

    ... bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts give rise to all of the formed elements in blood. If a hemocytoblast commits to becoming a cell called a proerythroblast, it will develop into a new red blood cell. The formation of a red blood ...

  4. Criticality in cell differentiation

    Indian Academy of Sciences (India)

    Indrani Bose

    2017-11-09

    Nov 9, 2017 ... Cell differentiation is an important process in living organisms. Differentiation is mostly based on binary decisions with the progenitor cells choosing between two specific lineages. The differentiation dynamics have both deterministic and stochastic components. Several theoretical studies suggest that cell ...

  5. NCAM regulates cell motility

    DEFF Research Database (Denmark)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna

    2002-01-01

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells independe...

  6. Dazlin' pluripotent stem cells

    NARCIS (Netherlands)

    Welling, M.A.

    2014-01-01

    Pluripotent embryonic stem cells (ESCs) can be isolated from the inner cell mass (ICM) of blastocyst embryos and differentiate into all three germ layers in vitro. However, despite their similar origin, mouse embryonic stem cells represent a more naïve ICM-like pluripotent state whereas human

  7. Textured perovskite cells

    NARCIS (Netherlands)

    Deelen, J. van; Tezsevin, Y.; Barink, M.

    2017-01-01

    Most research of texturization of solar cells has been devoted to Si based cells. For perovskites, it was assumed that texturization would not have much of an impact because of the relatively low refractive indexes lead to relatively low reflection as compared to the Si based cells. However, our

  8. Cell phones and cancer

    Science.gov (United States)

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of ...

  9. Stem cell heterogeneity revealed

    DEFF Research Database (Denmark)

    Andersen, Marianne S; Jensen, Kim B

    2016-01-01

    The skin forms a protective, water-impermeable barrier consisting of heavily crosslinked epithelial cells. However, the specific role of stem cells in sustaining this barrier remains a contentious issue. A detailed analysis of the interfollicular epidermis now proposes a model for how a composite...... of cells with different properties are involved in its maintenance....

  10. Criticality in cell differentiation

    Indian Academy of Sciences (India)

    Cell differentiation is an important process in living organisms. Differentiation is mostly based on binary decisions with theprogenitor cells choosing between two specific lineages. The differentiation dynamics have both deterministic andstochastic components. Several theoretical studies suggest that cell differentiation is a ...

  11. Sickle Cell Disease

    Science.gov (United States)

    ... the sickle cell gene on to their kids. Symptoms of sickle cell disease Anemia is a common symptom of SCD. It occurs from a lack of ... SCD cannot be prevented since it is genetic. Sickle cell disease treatment ... of SCD, your symptoms, and your overall health. Most treatment options aim ...

  12. Sickle cell test

    Science.gov (United States)

    ... blood cells that carries oxygen. In sickle cell disease, a person has two abnormal hemoglobin S genes. A person with sickle cell trait has only one of these abnormal genes and no symptoms, or only mild ones. This test does not ...

  13. Aneuploidy in stem cells

    NARCIS (Netherlands)

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to

  14. Biomarkers of cell senescence

    Science.gov (United States)

    Dirmi, Goberdhan P.; Campisi, Judith; Peacocke, Monica

    1996-01-01

    The present invention provides a biomarker system for the in vivo and in vitro assessment of cell senescence. In the method of the present invention, .beta.-galactosidase activity is utilized as a means by which cell senescence may be assessed either in in vitro cell cultures or in vivo.

  15. Mouse Leydig Tumor Cells

    Directory of Open Access Journals (Sweden)

    Bo-Syong Pan

    2011-01-01

    Full Text Available Cordycepin is a natural pure compound extracted from Cordyceps sinensis (CS. We have demonstrated that CS stimulates steroidogenesis in primary mouse Leydig cell and activates apoptosis in MA-10 mouse Leydig tumor cells. It is highly possible that cordycepin is the main component in CS modulating Leydig cell functions. Thus, our aim was to investigate the steroidogenic and apoptotic effects with potential mechanism of cordycepin on MA-10 mouse Leydig tumor cells. Results showed that cordycepin significantly stimulated progesterone production in dose- and time-dependent manners. Adenosine receptor (AR subtype agonists were further used to treat MA-10 cells, showing that A1, A 2A , A 2B , and A3, AR agonists could stimulate progesterone production. However, StAR promoter activity and protein expression remained of no difference among all cordycepin treatments, suggesting that cordycepin might activate AR, but not stimulated StAR protein to regulate MA-10 cell steroidogenesis. Meanwhile, cordycepin could also induce apoptotic cell death in MA-10 cells. Moreover, four AR subtype agonists induced cell death in a dose-dependent manner, and four AR subtype antagonists could all rescue cell death under cordycepin treatment in MA-10 cells. In conclusion, cordycepin could activate adenosine subtype receptors and simultaneously induce steroidogenesis and apoptosis in MA-10 mouse Leydig tumor cells.

  16. Mutagenesis in mammalian cells

    International Nuclear Information System (INIS)

    Burki, H.J.

    1981-01-01

    Mutagenic processes in synchronous cultures of Chinese hamster ovary cells have been studied. There is a difference in the induction of mutants by ultraviolet light during the cell cycle. There appears to be a sensitive period in the middle of the G1 stage of the cell cycle suggesting some mutagenic mechanism is present at that time. Studies indicate that mutation induction during the cell cycle is also mutagen specific since exposure to ethyl nitrosourea in the same system produces different results. Two clones have been isolated which are ultrasensitive to ultraviolet light. These cells are being used to determine if this hypermutability is cell-cycle dependent, related to cell cycle biochemistry, or to repair processes independent of cell cycle. Tritium and bromodeoxyuridine induced damage to synchronously dividing cell cultures are also being studied in relation to DNA replication. Cell killing by ionizing radiation is also related to the cell cycle. Sensitive times in the cell cycle for mutation induction by ionization radiation are identified

  17. Mast cell activation disease

    African Journals Online (AJOL)

    EL-HAKIM

    Blood basophils also participate in allergic and other inflammatory reactions in the same way as mast cells.4. The capacity of mast cells and basophil to release mediators of anaphylaxis in response to cell activation, also termed releasability, depends on a number of different factors, including the primary underlying disease ...

  18. Nanostructured Organic Solar Cells

    DEFF Research Database (Denmark)

    Radziwon, Michal Jędrzej; Rubahn, Horst-Günter; Madsen, Morten

    Recent forecasts for alternative energy generation predict emerging importance of supporting state of art photovoltaic solar cells with their organic equivalents. Despite their significantly lower efficiency, number of application niches are suitable for organic solar cells. This work reveals...... the principles of bulk heterojunction organic solar cells fabrication as well as summarises major differences in physics of their operation....

  19. Spermatogonial stem cells

    NARCIS (Netherlands)

    de rooij, D. G.; Grootegoed, J. A.

    1998-01-01

    The mammalian seminiferous epithelium consists of a highly complex yet well-organized cell population, with germ cells in mitosis and meiosis and postmeiotic cells undergoing transformation to become spermatozoa. To study the factors which control renewal and differentiation of spermatogonial stem

  20. Place Cells, Grid Cells, Attractors, and Remapping

    Directory of Open Access Journals (Sweden)

    Kathryn J. Jeffery

    2011-01-01

    Full Text Available Place and grid cells are thought to use a mixture of external sensory information and internal attractor dynamics to organize their activity. Attractor dynamics may explain both why neurons react coherently following sufficiently large changes to the environment (discrete attractors and how firing patterns move smoothly from one representation to the next as an animal moves through space (continuous attractors. However, some features of place cell behavior, such as the sometimes independent responsiveness of place cells to environmental change (called “remapping”, seem hard to reconcile with attractor dynamics. This paper suggests that the explanation may be found in an anatomical separation of the two attractor systems coupled with a dynamic contextual modulation of the connection matrix between the two systems, with new learning being back-propagated into the matrix. Such a scheme could explain how place cells sometimes behave coherently and sometimes independently.

  1. When Blood Cells Bend: Understanding Sickle Cell Disease

    Science.gov (United States)

    ... Subscribe April 2012 Print this issue When Blood Cells Bend Understanding Sickle Cell Disease Send us your ... Diabetes? Sound Health Wise Choices Living with Sickle Cell Disease See a sickle cell disease expert regularly. ...

  2. Fuel cell catalyst degradation

    DEFF Research Database (Denmark)

    Arenz, Matthias; Zana, Alessandro

    2016-01-01

    Fuel cells are an important piece in our quest for a sustainable energy supply. Although there are several different types of fuel cells, the by far most popular is the proton exchange membrane fuel cell (PEMFC). Among its many favorable properties are a short start up time and a high power density...... increasing focus. Activity of the catalyst is important, but stability is essential. In the presented perspective paper, we review recent efforts to investigate fuel cell catalysts ex-situ in electrochemical half-cell measurements. Due to the amount of different studies, this review has no intention to give...

  3. Transparent ultraviolet photovoltaic cells.

    Science.gov (United States)

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future.

  4. Human mesenchymal stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem; Kassem, Moustapha

    2008-01-01

    Mesenchymal stem cells (MSC) are a group of clonogenic cells present among the bone marrow stroma and capable of multilineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. Due to their ease of isolation and their differentiation potential, MSC are being...... introduced into clinical medicine in variety of applications and through different ways of administration. Here, we discuss approaches for isolation, characterization and directing differentiation of human mesenchymal stem cells (hMSC). An update of the current clinical use of the cells is also provided....

  5. Fuel Cell/Electrochemical Cell Voltage Monitor

    Science.gov (United States)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  6. Pancreatic cancer stem cells.

    Science.gov (United States)

    Lee, Cheong J; Dosch, Joseph; Simeone, Diane M

    2008-06-10

    Cellular heterogeneity in cancer was observed decades ago by studies in mice which showed that distinct subpopulations of cells within a tumor mass are capable of driving tumorigenesis. Conceptualized from this finding was the stem-cell hypothesis for cancer, which suggests that only a specific subset of cancer cells within each tumor is responsible for tumor initiation and propagation, termed tumor initiating cells or cancer stem cells (CSCs). Recent data has been provided to support the existence of CSCs in human blood cell-derived cancers and solid organ tumors of the breast, brain, prostate, colon, and skin. Study of human pancreatic cancers has also revealed a specific subpopulation of cancer cells that possess the characteristics of CSCs. These pancreatic cancer stem cells express the cell surface markers CD44, CD24, and epithelial-specific antigen, and represent 0.5% to 1.0% of all pancreatic cancer cells. Along with the properties of self-renewal and multilineage differentiation, pancreatic CSCs display upregulation of important developmental genes that maintain self-renewal in normal stem cells, including Sonic hedgehog (SHH) and BMI-1. Signaling cascades that are integral in tumor metastasis are also upregulated in the pancreatic CSC. Understanding the biologic behavior and the molecular pathways that regulate growth, survival, and metastasis of pancreatic CSCs will help to identify novel therapeutic approaches to treat this dismal disease.

  7. The Human Cell Atlas.

    Science.gov (United States)

    Regev, Aviv; Teichmann, Sarah A; Lander, Eric S; Amit, Ido; Benoist, Christophe; Birney, Ewan; Bodenmiller, Bernd; Campbell, Peter; Carninci, Piero; Clatworthy, Menna; Clevers, Hans; Deplancke, Bart; Dunham, Ian; Eberwine, James; Eils, Roland; Enard, Wolfgang; Farmer, Andrew; Fugger, Lars; Göttgens, Berthold; Hacohen, Nir; Haniffa, Muzlifah; Hemberg, Martin; Kim, Seung; Klenerman, Paul; Kriegstein, Arnold; Lein, Ed; Linnarsson, Sten; Lundberg, Emma; Lundeberg, Joakim; Majumder, Partha; Marioni, John C; Merad, Miriam; Mhlanga, Musa; Nawijn, Martijn; Netea, Mihai; Nolan, Garry; Pe'er, Dana; Phillipakis, Anthony; Ponting, Chris P; Quake, Stephen; Reik, Wolf; Rozenblatt-Rosen, Orit; Sanes, Joshua; Satija, Rahul; Schumacher, Ton N; Shalek, Alex; Shapiro, Ehud; Sharma, Padmanee; Shin, Jay W; Stegle, Oliver; Stratton, Michael; Stubbington, Michael J T; Theis, Fabian J; Uhlen, Matthias; van Oudenaarden, Alexander; Wagner, Allon; Watt, Fiona; Weissman, Jonathan; Wold, Barbara; Xavier, Ramnik; Yosef, Nir

    2017-12-05

    The recent advent of methods for high-throughput single-cell molecular profiling has catalyzed a growing sense in the scientific community that the time is ripe to complete the 150-year-old effort to identify all cell types in the human body. The Human Cell Atlas Project is an international collaborative effort that aims to define all human cell types in terms of distinctive molecular profiles (such as gene expression profiles) and to connect this information with classical cellular descriptions (such as location and morphology). An open comprehensive reference map of the molecular state of cells in healthy human tissues would propel the systematic study of physiological states, developmental trajectories, regulatory circuitry and interactions of cells, and also provide a framework for understanding cellular dysregulation in human disease. Here we describe the idea, its potential utility, early proofs-of-concept, and some design considerations for the Human Cell Atlas, including a commitment to open data, code, and community.

  8. Cell and Tissue Engineering

    CERN Document Server

    2012-01-01

    Cell and Tissue Engineering” introduces the principles and new approaches in cell and tissue engineering. It includes both the fundamentals and the current trends in cell and tissue engineering, in a way useful both to a novice and an expert in the field. The book is composed of 13 chapters all of which are written by the leading experts. It is organized to gradually assemble an insight in cell and tissue function starting form a molecular nano-level, extending to a cellular micro-level and finishing at the tissue macro-level. In specific, biological, physiological, biophysical, biochemical, medical, and engineering aspects are covered from the standpoint of the development of functional substitutes of biological tissues for potential clinical use. Topics in the area of cell engineering include cell membrane biophysics, structure and function of the cytoskeleton, cell-extracellular matrix interactions, and mechanotransduction. In the area of tissue engineering the focus is on the in vitro cultivation of ...

  9. Enteroendocrine cell types revisited

    DEFF Research Database (Denmark)

    Engelstoft, Maja S; Egerod, Kristoffer Lihme; Lund, Mari L

    2013-01-01

    The GI-tract is profoundly involved in the control of metabolism through peptide hormones secreted from enteroendocrine cells scattered throughout the gut mucosa. A large number of recently generated transgenic reporter mice have allowed for direct characterization of biochemical and cell...... biological properties of these previously highly elusive enteroendocrine cells. In particular the surprisingly broad co-expression of six functionally related hormones in the intestinal enteroendocrine cells indicates that it should be possible to control not only the hormone secretion but also the type...... and number of enteroendocrine cells. However, this will require a more deep understanding of the factors controlling differentiation, gene expression and specification of the enteroendocrine cells during their weekly renewal from progenitor cells in the crypts of the mucosa....

  10. Stem Cell Pathology.

    Science.gov (United States)

    Fu, Dah-Jiun; Miller, Andrew D; Southard, Teresa L; Flesken-Nikitin, Andrea; Ellenson, Lora H; Nikitin, Alexander Yu

    2018-01-24

    Rapid advances in stem cell biology and regenerative medicine have opened new opportunities for better understanding disease pathogenesis and the development of new diagnostic, prognostic, and treatment approaches. Many stem cell niches are well defined anatomically, thereby allowing their routine pathological evaluation during disease initiation and progression. Evaluation of the consequences of genetic manipulations in stem cells and investigation of the roles of stem cells in regenerative medicine and pathogenesis of various diseases such as cancer require significant expertise in pathology for accurate interpretation of novel findings. Therefore, there is an urgent need for developing stem cell pathology as a discipline to facilitate stem cell research and regenerative medicine. This review provides examples of anatomically defined niches suitable for evaluation by diagnostic pathologists, describes neoplastic lesions associated with them, and discusses further directions of stem cell pathology.

  11. Mammary gland stem cells

    DEFF Research Database (Denmark)

    Fridriksdottir, Agla J R; Petersen, Ole W; Rønnov-Jessen, Lone

    2011-01-01

    Distinct subsets of cells, including cells with stem cell-like properties, have been proposed to exist in normal human breast epithelium and breast carcinomas. The cellular origins of epithelial cells contributing to gland development, tissue homeostasis and cancer are, however, still poorly...... understood. The mouse is a widely used model of mammary gland development, both directly by studying the mouse mammary epithelial cells themselves and indirectly, by studying development, morphogenesis, differentiation and carcinogenesis of xenotransplanted human breast epithelium in vivo. While in early...... studies, human or mouse epithelium was implanted as fragments into the mouse gland, more recent technical progress has allowed the self-renewal capacity and differentiation potential of distinct cell populations or even individual cells to be interrogated. Here, we review and discuss similarities...

  12. Human regulatory B cells control the TFH cell response.

    Science.gov (United States)

    Achour, Achouak; Simon, Quentin; Mohr, Audrey; Séité, Jean-François; Youinou, Pierre; Bendaoud, Boutahar; Ghedira, Ibtissem; Pers, Jacques-Olivier; Jamin, Christophe

    2017-07-01

    Follicular helper T (T FH ) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of T FH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on T FH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate T FH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing T FH cell maturation. In cocultures they differentiated B cells into CD138 + plasma and IgD - CD27 + memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented T FH cell development. Added to T FH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3 + CXCR5 + PD-1 + follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on T FH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Human Breg cells control T FH cell maturation, expand follicular regulatory T cells, and inhibit the T FH cell-mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the T FH cell-dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  13. Well-Controlled Cell-Trapping Systems for Investigating Heterogeneous Cell-Cell Interactions.

    Science.gov (United States)

    Kamiya, Koki; Abe, Yuta; Inoue, Kosuke; Osaki, Toshihisa; Kawano, Ryuji; Miki, Norihisa; Takeuchi, Shoji

    2018-03-01

    Microfluidic systems have been developed for patterning single cells to study cell-cell interactions. However, patterning multiple types of cells to understand heterogeneous cell-cell interactions remains difficult. Here, it is aimed to develop a cell-trapping device to assemble multiple types of cells in the well-controlled order and morphology. This device mainly comprises a parylene sheet for assembling cells and a microcomb for controlling the cell-trapping area. The cell-trapping area is controlled by moving the parylene sheet on an SU-8 microcomb using tweezers. Gentle downward flow is used as a driving force for the cell-trapping. The assembly of cells on a parylene sheet with round and line-shaped apertures is demonstrated. The cell-cell contacts of the trapped cells are then investigated by direct cell-cell transfer of calcein via connexin nanopores. Finally, using the device with a system for controlling the cell-trapping area, three different types of cells in the well-controlled order are assembled. The correct cell order rate obtained using the device is 27.9%, which is higher than that obtained without the sliding parylene system (0.74%). Furthermore, the occurrence of cell-cell contact between the three cell types assembled is verified. This cell-patterning device will be a useful tool for investigating heterogeneous cell-cell interactions. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Involvement of plant stem cells or stem cell-like cells in dedifferentiation

    Directory of Open Access Journals (Sweden)

    Fangwei eJiang

    2015-11-01

    Full Text Available Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation.

  15. What is Sickle Cell Disease?

    Science.gov (United States)

    ... Congenital Anemias Including Sickle Cell Disease (SCD) and Beta-Thalassemia. Are you an adult with sickle cell disease ... Severe Congenital Anemias Including Sickle Cell Disease and Beta-Thalassemia. Are you 16 or older with sickle cell ...

  16. Membrane Cells for Brine Electrolysis.

    Science.gov (United States)

    Tingle, M.

    1982-01-01

    Membrane cells were developed as alternatives to mercury and diaphragm cells for the electrolysis of brine. Compares the three types of cells, focusing on the advantages and disadvantages of membrane cells. (JN)

  17. Leveling of battery load and extension of battery life by serial connection of electric double layer capacitors with batteries for electric vehicles. Experimental results on the small model; Denki jidoshayo denchi to denki nijuso capacitor no chokuretsu setsuzoku ni yoru denchi futan no heijunka oyobi denchijumyo no enshinka. (kogata model ni yoru jikken seika). Kogata model ni yoru jikken seika

    Energy Technology Data Exchange (ETDEWEB)

    Takehara, J.; Okubo, N.; Miyaoka, K. [Chugoku Electric Power Co. Inc., Hiroshima (Japan)

    1996-10-25

    The load leveling method of batteries for electric vehicles was studied for extension of a battery life and mileage every charging. Under large load fluctuation conditions such as deceleration and acceleration, use of electric power sources other than battery for peek load at acceleration can improve a battery life, output power capacity and mileage every charging. Combination of effective recovery of regenerative power at deceleration with its discharge at acceleration is one of the effective methods. The electric double layer capacitors are serially connected with the batteries, regenerative power is charged only into the capacitors, and both voltages of the battery and capacitor are applied to a power circuit. Battery load is reduced by load on the capacitor. Until the capacitor is re-charged by regenerative power after full discharge, power is supplied only by battery through a diode. Capacitor power is used as effectively as possible until approaching considerably low voltage. As peak load of the battery is reduced by 30%, the mileage increases by 5.7%, and the battery cycle life becomes 1.5 times longer. 7 refs., 5 figs., 3 tabs.

  18. Epithelial Cell Cultures

    Directory of Open Access Journals (Sweden)

    Imran S. Chaudhry

    2011-01-01

    Full Text Available The biological effects of only a finite number of tobacco toxins have been studied. Here, we describe exposure of cultures of human bronchial epithelial cells to low concentrations of tobacco carcinogens: nickel sulphate, benzo(bfluoranthene, N-nitrosodiethylamine, and 4-(methylnitrosamino-1-(3-pyridyl-1-butanone (NNK. After a 24-hour exposure, EGFR was expressed in cell membrane and cytoplasm, BCL-2 was expressed only in the irregular nuclei of large atypical cells, MKI67 was expressed in nuclei with no staining in larger cells, cytoplasmic BIRC5 with stronger nuclear staining was seen in large atypical cells, and nuclear TP53 was strongly expressed in all cells. After only a 24-hour exposure, cells exhibited atypical nuclear and cytoplasmic features. After a 48-hour exposure, EGFR staining was localized to the nucleus, BCL-2 was slightly decreased in intensity, BIRC5 was localized to the cytoplasm, and TP53 staining was increased in small and large cells. BCL2L1 was expressed in both the cytoplasm and nuclei of cells at 24- and 48-hour exposures. We illustrate that short-termexposure of a bronchial epithelial cell line to smoking-equivalent concentrations of tobacco carcinogens alters the expression of key proliferation regulatory genes, EGFR, BCL-2, BCL2L1, BIRC5, TP53, and MKI67, similar to that reported in biopsy specimens of pulmonary epithelium described to be preneoplastic lesions.

  19. Mast Cell Function

    Science.gov (United States)

    da Silva, Elaine Zayas Marcelino; Jamur, Maria Célia

    2014-01-01

    Since first described by Paul Ehrlich in 1878, mast cells have been mostly viewed as effectors of allergy. It has been only in the past two decades that mast cells have gained recognition for their involvement in other physiological and pathological processes. Mast cells have a widespread distribution and are found predominantly at the interface between the host and the external environment. Mast cell maturation, phenotype and function are a direct consequence of the local microenvironment and have a marked influence on their ability to specifically recognize and respond to various stimuli through the release of an array of biologically active mediators. These features enable mast cells to act as both first responders in harmful situations as well as to respond to changes in their environment by communicating with a variety of other cells implicated in physiological and immunological responses. Therefore, the critical role of mast cells in both innate and adaptive immunity, including immune tolerance, has gained increased prominence. Conversely, mast cell dysfunction has pointed to these cells as the main offenders in several chronic allergic/inflammatory disorders, cancer and autoimmune diseases. This review summarizes the current knowledge of mast cell function in both normal and pathological conditions with regards to their regulation, phenotype and role. PMID:25062998

  20. CELL RESPIRATION STUDIES

    Science.gov (United States)

    Daland, Geneva A.; Isaacs, Raphael

    1927-01-01

    1. The oxygen consumption of blood of normal individuals, when the hemoglobin is saturated with oxygen, is practically zero within the limits of experimental error of the microspirometer used. 2. The oxygen consumed in a microspirometer by the blood of patients with chronic myelogenous leucemia with a high white blood cell count, and of one with leucocytosis from sepsis, was proportional to the number of adult polymorphonuclear neutrophils in the blood. 3. No correlation could be made between the rate of oxygen absorption and the total number of white blood cells in the blood, or the total number of immature cells, or the number of red blood cells, or the amount of oxyhemoglobin. 4. The blood of patients with chronic myelogenous leucemia continued to use oxygen in the microspirometer longer than that of normal individuals, and the hemoglobin, in the leucemic bloods, became desaturated even though exposed to air. 5. In blood in which the bulk. of the cells were immature and the mature cells few, the oxygen consumption was lower than in blood in which the mature cells predominated. The rate of oxygen consumption of the immature cells was relatively low as compared to the mature. 6. The slower rate of oxygen absorption by the immature leucocytes in chronic myelogenous leucemia as compared to the mature cells, places them, in accord with Warburg's reports, in the class of the malignant tissues in this respect rather than in the group of young or embryonic cells. PMID:19869329

  1. Simple Cell Balance Circuit

    Science.gov (United States)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  2. NKT cells in leishmaniasis.

    Science.gov (United States)

    Zamora-Chimal, Jaime; Hernández-Ruiz, Joselín; Becker, Ingeborg

    2017-04-01

    The role of NKT cells in the resistance or susceptibility towards Leishmania infections remains to be defined, since controversial data persist. The response of these cells seems to depend on many variables such as the infection site, the number of infecting parasites, the virulence of the strain and the Leishmania species. We here revise the activation pathways leading to NKT cell activation. NKT cells can be activated by the direct pathway, in which Leishmania glycolipids are presented by CD1d molecules on antigen presenting cells, such as dendritic cells (DC), leading to the secretion of diverse cytokines by NKT. NKT cells can also be activated by the indirect pathway, in which Leishmania glycolipids, such as LPG, stimulate TLR2 in DC, inducing their IL-12 production, which in turn activates NKT cells. The review further analyzes the role of NKT cells in disease development, both in humans as in mouse models. Finally we propose the activation of NKT cells for controlling Leishmania infections. Copyright © 2016 Elsevier GmbH. All rights reserved.

  3. Biology of Schwann cells.

    Science.gov (United States)

    Kidd, Grahame J; Ohno, Nobuhiko; Trapp, Bruce D

    2013-01-01

    The fundamental roles of Schwann cells during peripheral nerve formation and regeneration have been recognized for more than 100 years, but the cellular and molecular mechanisms that integrate Schwann cell and axonal functions continue to be elucidated. Derived from the embryonic neural crest, Schwann cells differentiate into myelinating cells or bundle multiple unmyelinated axons into Remak fibers. Axons dictate which differentiation path Schwann cells follow, and recent studies have established that axonal neuregulin1 signaling via ErbB2/B3 receptors on Schwann cells is essential for Schwann cell myelination. Extracellular matrix production and interactions mediated by specific integrin and dystroglycan complexes are also critical requisites for Schwann cell-axon interactions. Myelination entails expansion and specialization of the Schwann cell plasma membrane over millimeter distances. Many of the myelin-specific proteins have been identified, and transgenic manipulation of myelin genes have provided novel insights into myelin protein function, including maintenance of axonal integrity and survival. Cellular events that facilitate myelination, including microtubule-based protein and mRNA targeting, and actin based locomotion, have also begun to be understood. Arguably, the most remarkable facet of Schwann cell biology, however, is their vigorous response to axonal damage. Degradation of myelin, dedifferentiation, division, production of axonotrophic factors, and remyelination all underpin the substantial regenerative capacity of the Schwann cells and peripheral nerves. Many of these properties are not shared by CNS fibers, which are myelinated by oligodendrocytes. Dissecting the molecular mechanisms responsible for the complex biology of Schwann cells continues to have practical benefits in identifying novel therapeutic targets not only for Schwann cell-specific diseases but other disorders in which axons degenerate. Copyright © 2013 Elsevier B.V. All rights

  4. Solar cell shingle

    Science.gov (United States)

    Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G. (Inventor)

    1977-01-01

    A solar cell shingle was made of an array of solar cells on a lower portion of a substantially rectangular shingle substrate made of fiberglass cloth or the like. The solar cells may be encapsulated in flourinated ethylene propylene or some other weatherproof translucent or transparent encapsulant to form a combined electrical module and a roof shingle. The interconnected solar cells were connected to connectors at the edge of the substrate through a connection to a common electrical bus or busses. An overlap area was arranged to receive the overlap of a cooperating similar shingle so that the cell portion of the cooperating shingle may overlie the overlap area of the roof shingle. Accordingly, the same shingle serves the double function of an ordinary roof shingle which may be applied in the usual way and an array of cooperating solar cells from which electrical energy may be collected.

  5. NCAM regulates cell motility

    DEFF Research Database (Denmark)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna

    2002-01-01

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells...... independently of homophilic NCAM interactions. Expression of the transmembrane 140 kDa isoform of NCAM (NCAM-140) caused a significant reduction in cellular motility, probably through interference with factors regulating cellular attachment, as NCAM-140-expressing cells exhibited a decreased attachment...... to a fibronectin substratum compared with NCAM-negative cells. Ectopic expression of the cytoplasmic part of NCAM-140 also inhibited cell motility, presumably via the non-receptor tyrosine kinase p59(fyn) with which NCAM-140 interacts. Furthermore, we showed that the extracellular part of NCAM acted as a paracrine...

  6. The human cell atlas

    DEFF Research Database (Denmark)

    Regev, Aviv; Teichmann, Sarah A.; Lander, Eric S.

    2017-01-01

    The recent advent of methods for high-throughput single-cell molecular profiling has catalyzed a growing sense in the scientific community that the time is ripe to complete the 150-year-old effort to identify all cell types in the human body. The Human Cell Atlas Project is an international...... collaborative effort that aims to define all human cell types in terms of distinctive molecular profiles (such as gene expression profiles) and to connect this information with classical cellular descriptions (such as location and morphology). An open comprehensive reference map of the molecular state of cells...... in healthy human tissues would propel the systematic study of physiological states, developmental trajectories, regulatory circuitry and interactions of cells, and also provide a framework for understanding cellular dysregulation in human disease. Here we describe the idea, its potential utility, early...

  7. Cell Factory Engineering

    DEFF Research Database (Denmark)

    Davy, Anne Mathilde; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    2017-01-01

    Rational approaches to modifying cells to make molecules of interest are of substantial economic and scientific interest. Most of these efforts aim at the production of native metabolites, expression of heterologous biosynthetic pathways, or protein expression. Reviews of these topics have largely...... focused on individual strategies or cell types, but collectively they fall under the broad umbrella of a growing field known as cell factory engineering. Here we condense >130 reviews and key studies in the art into a meta-review of cell factory engineering. We identified 33 generic strategies...... in the field, all applicable to multiple types of cells and products, and proven successful in multiple major cell types. These apply to three major categories: production of native metabolites and/or bioactives, heterologous expression of biosynthetic pathways, and protein expression. This meta...

  8. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Amitkumar B Pandav

    2012-01-01

    Full Text Available Plasma cell granuloma, also known as inflammatory pseudotumor is a tumor-like lesion that manifests primarily in the lungs. But it may occur in various other anatomic locations like orbit, head and neck, liver and rarely in the oral cavity. We here report an exceedingly rare case of gingival plasma cell granuloma in a 58 year old woman who presented with upper gingival polypoidal growth. The histopathological examination revealed a mass composed of proliferation of benign spindle mesenchymal cells in a loose myxoid and fibrocollagenous stroma along with dense infiltrate of chronic inflammatory cells predominantly containing plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma.

  9. Cell Therapy in Dermatology

    Science.gov (United States)

    Petrof, Gabriela; Abdul-Wahab, Alya; McGrath, John A.

    2014-01-01

    Harnessing the regenerative capacity of keratinocytes and fibroblasts from human skin has created new opportunities to develop cell-based therapies for patients. Cultured cells and bioengineered skin products are being used to treat patients with inherited and acquired skin disorders associated with defective skin, and further clinical trials of new products are in progress. The capacity of extracutaneous sources of cells such as bone marrow is also being investigated for its plasticity in regenerating skin, and new strategies, such as the derivation of inducible pluripotent stem cells, also hold great promise for future cell therapies in dermatology. This article reviews some of the preclinical and clinical studies and future directions relating to cell therapy in dermatology, particularly for inherited skin diseases associated with fragile skin and poor wound healing. PMID:24890834

  10. Basal cell carcinoma of the skin with areas of squamous cell carcinoma: a basosquamous cell carcinoma?

    OpenAIRE

    de Faria, J

    1985-01-01

    The diagnosis of basosquamous cell carcinoma is controversial. A review of cases of basal cell carcinoma showed 23 cases that had conspicuous areas of squamous cell carcinoma. This was distinguished from squamous differentiation and keratotic basal cell carcinoma by a comparative study of 40 cases of compact lobular and 40 cases of keratotic basal cell carcinoma. Areas of intermediate tumour differentiation between basal cell and squamous cell carcinoma were found. Basal cell carcinomas with ...

  11. Synaptic Cell Adhesion

    OpenAIRE

    Missler, Markus; Südhof, Thomas C.; Biederer, Thomas

    2012-01-01

    Chemical synapses are asymmetric intercellular junctions that mediate synaptic transmission. Synaptic junctions are organized by trans-synaptic cell adhesion molecules bridging the synaptic cleft. Synaptic cell adhesion molecules not only connect pre- and postsynaptic compartments, but also mediate trans-synaptic recognition and signaling processes that are essential for the establishment, specification, and plasticity of synapses. A growing number of synaptic cell adhesion molecules that inc...

  12. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  13. Different cell fates from cell-cell interactions: core architectures of two-cell bistable networks.

    Science.gov (United States)

    Rouault, Hervé; Hakim, Vincent

    2012-02-08

    The acquisition of different fates by cells that are initially in the same state is central to development. Here, we investigate the possible structures of bistable genetic networks that can allow two identical cells to acquire different fates through cell-cell interactions. Cell-autonomous bistable networks have been previously sampled using an evolutionary algorithm. We extend this evolutionary procedure to take into account interactions between cells. We obtain a variety of simple bistable networks that we classify into major subtypes. Some have long been proposed in the context of lateral inhibition through the Notch-Delta pathway, some have been more recently considered and others appear to be new and based on mechanisms not previously considered. The results highlight the role of posttranscriptional interactions and particularly of protein complexation and sequestration, which can replace cooperativity in transcriptional interactions. Some bistable networks are entirely based on posttranscriptional interactions and the simplest of these is found to lead, upon a single parameter change, to oscillations in the two cells with opposite phases. We provide qualitative explanations as well as mathematical analyses of the dynamical behaviors of various created networks. The results should help to identify and understand genetic structures implicated in cell-cell interactions and differentiation. Copyright © 2012 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  14. Bacterial Cell Mechanics.

    Science.gov (United States)

    Auer, George K; Weibel, Douglas B

    2017-07-25

    Cellular mechanical properties play an integral role in bacterial survival and adaptation. Historically, the bacterial cell wall and, in particular, the layer of polymeric material called the peptidoglycan were the elements to which cell mechanics could be primarily attributed. Disrupting the biochemical machinery that assembles the peptidoglycan (e.g., using the β-lactam family of antibiotics) alters the structure of this material, leads to mechanical defects, and results in cell lysis. Decades after the discovery of peptidoglycan-synthesizing enzymes, the mechanisms that underlie their positioning and regulation are still not entirely understood. In addition, recent evidence suggests a diverse group of other biochemical elements influence bacterial cell mechanics, may be regulated by new cellular mechanisms, and may be triggered in different environmental contexts to enable cell adaptation and survival. This review summarizes the contributions that different biomolecular components of the cell wall (e.g., lipopolysaccharides, wall and lipoteichoic acids, lipid bilayers, peptidoglycan, and proteins) make to Gram-negative and Gram-positive bacterial cell mechanics. We discuss the contribution of individual proteins and macromolecular complexes in cell mechanics and the tools that make it possible to quantitatively decipher the biochemical machinery that contributes to bacterial cell mechanics. Advances in this area may provide insight into new biology and influence the development of antibacterial chemotherapies.

  15. Atmospheric Absorption Cell Characterization.

    Science.gov (United States)

    1982-06-01

    was adequate for making empty cell measurements and filling the cell with artificial atmospheres. The procedure used in pumping and fillin the cell...carbon dioxide, nitrogen, and nitrous oxide. The artificial atmospheres in the cell used for these measurements are summarized in Table IV. Figures...LD_l -_10J J« LUZ . jr-U «—• »r—• «-CD CO — Q- —a CD -j" \\z — OC I — h- \\_IC\\J CM LUD -ÜU T 1 r 00*001 00󈧌 00*09 00*0

  16. Cancer stem cell metabolism.

    Science.gov (United States)

    Peiris-Pagès, Maria; Martinez-Outschoorn, Ubaldo E; Pestell, Richard G; Sotgia, Federica; Lisanti, Michael P

    2016-05-24

    Cancer is now viewed as a stem cell disease. There is still no consensus on the metabolic characteristics of cancer stem cells, with several studies indicating that they are mainly glycolytic and others pointing instead to mitochondrial metabolism as their principal source of energy. Cancer stem cells also seem to adapt their metabolism to microenvironmental changes by conveniently shifting energy production from one pathway to another, or by acquiring intermediate metabolic phenotypes. Determining the role of cancer stem cell metabolism in carcinogenesis has become a major focus in cancer research, and substantial efforts are conducted towards discovering clinical targets.

  17. Nanocrystal Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ilan [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

  18. Littoral Cells 2005

    Data.gov (United States)

    California Natural Resource Agency — Littoral cells along the California Coast. Originally digitized by Melanie Coyne from the Assessment and Atlas of Shoreline Erosion Along the California Coast...

  19. Microencapsulation Of Living Cells

    Science.gov (United States)

    Chang, Manchium; Kendall, James M.; Wang, Taylor G.

    1989-01-01

    In experimental technique, living cells and other biological materials encapsulated within submillimeter-diameter liquid-filled spheres. Sphere material biocompatible, tough, and compliant. Semipermeable, permitting relatively small molecules to move into and out of sphere core but preventing passage of large molecules. New technique promises to make such spherical capsules at high rates and in uniform, controllable sizes. Capsules injected into patient through ordinary hypodermic needle. Promising application for technique in treatment of diabetes. Also used to encapsulate pituitary cells and thyroid hormone adrenocortical cells for treatment of other hormonal disorders, to encapsulate other secreting cells for transplantation, and to package variety of pharmaceutical products and agricultural chemicals for controlled release.

  20. Applications of Cell Microencapsulation.

    Science.gov (United States)

    Opara, Emmanuel C

    2017-01-01

    The goal of this chapter is to provide an overview of the different purposes for which the cell microencapsulation technology can be used. These include immunoisolation of non-autologous cells used for cell therapy; immobilization of cells for localized (targeted) delivery of therapeutic products to ablate, repair, or regenerate tissue; simultaneous delivery of multiple therapeutic agents in cell therapy; spatial compartmentalization of cells in complex tissue engineering; expansion of cells in culture; and production of different probiotics and metabolites for industrial applications. For each of these applications, specific examples are provided to illustrate how the microencapsulation technology can be utilized to achieve the purpose. However, successful use of the cell microencapsulation technology for whatever purpose will ultimately depend upon careful consideration for the choice of the encapsulating polymers, the method of fabrication (cross-linking) of the microbeads, which affects the permselectivity, the biocompatibility and the mechanical strength of the microbeads as well as environmental parameters such as temperature, humidity, osmotic pressure, and storage solutions.The various applications discussed in this chapter are illustrated in the different chapters of this book and where appropriate relevant images of the microencapsulation products are provided. It is hoped that this outline of the different applications of cell microencapsulation would provide a good platform for tissue engineers, scientists, and clinicians to design novel tissue constructs and products for therapeutic and industrial applications.

  1. A brief history of T cell help to B cells.

    Science.gov (United States)

    Crotty, Shane

    2015-03-01

    In celebration of the 50th anniversary of the discovery of B cells, I take a look back at the history of T cell help to B cells, which was discovered 47 years ago. In addition, I summarize and categorize the distinct molecules that are expressed by CD4(+) T cells that constitute 'help' to B cells, and particularly the molecules expressed by T follicular helper (TFH) cells, which are the specialized providers of help to B cells.

  2. Regulation of beta cell replication

    DEFF Research Database (Denmark)

    Lee, Ying C; Nielsen, Jens Høiriis

    2008-01-01

    Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

  3. Fuel Cell Demonstration Program

    Energy Technology Data Exchange (ETDEWEB)

    Gerald Brun

    2006-09-15

    In an effort to promote clean energy projects and aid in the commercialization of new fuel cell technologies the Long Island Power Authority (LIPA) initiated a Fuel Cell Demonstration Program in 1999 with six month deployments of Proton Exchange Membrane (PEM) non-commercial Beta model systems at partnering sites throughout Long Island. These projects facilitated significant developments in the technology, providing operating experience that allowed the manufacturer to produce fuel cells that were half the size of the Beta units and suitable for outdoor installations. In 2001, LIPA embarked on a large-scale effort to identify and develop measures that could improve the reliability and performance of future fuel cell technologies for electric utility applications and the concept to establish a fuel cell farm (Farm) of 75 units was developed. By the end of October of 2001, 75 Lorax 2.0 fuel cells had been installed at the West Babylon substation on Long Island, making it the first fuel cell demonstration of its kind and size anywhere in the world at the time. Designed to help LIPA study the feasibility of using fuel cells to operate in parallel with LIPA's electric grid system, the Farm operated 120 fuel cells over its lifetime of over 3 years including 3 generations of Plug Power fuel cells (Lorax 2.0, Lorax 3.0, Lorax 4.5). Of these 120 fuel cells, 20 Lorax 3.0 units operated under this Award from June 2002 to September 2004. In parallel with the operation of the Farm, LIPA recruited government and commercial/industrial customers to demonstrate fuel cells as on-site distributed generation. From December 2002 to February 2005, 17 fuel cells were tested and monitored at various customer sites throughout Long Island. The 37 fuel cells operated under this Award produced a total of 712,635 kWh. As fuel cell technology became more mature, performance improvements included a 1% increase in system efficiency. Including equipment, design, fuel, maintenance

  4. c-Myc-Dependent Cell Competition in Human Cancer Cells.

    Science.gov (United States)

    Patel, Manish S; Shah, Heta S; Shrivastava, Neeta

    2017-07-01

    Cell Competition is an interaction between cells for existence in heterogeneous cell populations of multicellular organisms. This phenomenon is involved in initiation and progression of cancer where heterogeneous cell populations compete directly or indirectly for the survival of the fittest based on differential gene expression. In Drosophila, cells having lower dMyc expression are eliminated by cell competition through apoptosis when present in the milieu of cells having higher dMyc expression. Thus, we designed a study to develop c-Myc (human homolog) dependent in vitro cell competition model of human cancer cells. Cells with higher c-Myc were transfected with c-myc shRNA to prepare cells with lower c-Myc and then co-cultured with the same type of cells having a higher c-Myc in equal ratio. Cells with lower c-Myc showed a significant decrease in numbers when compared with higher c-Myc cells, suggesting "loser" and "winner" status of cells, respectively. During microscopy, engulfment of loser cells by winner cells was observed with higher expression of JNK in loser cells. Furthermore, elimination of loser cells was prevented significantly, when co-cultured cells were treated with the JNK (apoptosis) inhibitor. Above results indicate elimination of loser cells in the presence of winner cells by c-Myc-dependent mechanisms of cell competition in human cancer cells. This could be an important mechanism in human tumors where normal cells are eliminated by c-Myc-overexpressed tumor cells. J. Cell. Biochem. 118: 1782-1791, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. Glycoprotein on cell surfaces

    International Nuclear Information System (INIS)

    Muramatsu, T.

    1975-01-01

    There are conjugated polysaccharides in cell membranes and outside of animal cells, and they play important role in the control of cell behavior. In this paper, the studies on the glycoprotein on cell surfaces are reported. It was found that the glycoprotein on cell surfaces have both N-glycoside type and O-glycoside type saccharic chains. Therefore it can be concluded that the basic structure of the saccharic chains in the glycoprotein on cell surfaces is similar to that of blood serum and body fluid. The main glycoprotein in the membranes of red blood corpuscles has been studied most in detail, and it also has both types of saccharic chains. The glycoprotein in liver cell membranes was found to have only the saccharic chains of acid type and to be in different pattern from that in endoplasmic reticula and nuclear membranes, which also has the saccharic chains of neutral type. The structure of the saccharic chains of H-2 antigen, i.e. the peculiar glycoprotein on the surfaces of lymph system cells, has been studied, and it is similar to the saccharic chains of glycoprotein in blood serum. The saccharic chain structures of H-2 antigen and TL antigen are different. TL, H-2 (D), Lna and H-2 (K) are the glycoprotein on cell surfaces, and are independent molecules. The analysis of the saccharic chain patterns on cell surfaces was carried out, and it was shown that the acid type saccharic chains were similar to those of ordinary glycoprotein, because the enzyme of pneumococci hydrolyzed most of the acid type saccharic chains. The change of the saccharic chain patterns of glycoprotein on cell surfaces owing to canceration and multiplication is complex matter. (Kako, I.)

  6. Molecular mechanisms controlling the cell cycle in embryonic stem cells.

    Science.gov (United States)

    Abdelalim, Essam M

    2013-12-01

    Embryonic stem (ES) cells are originated from the inner cell mass of a blastocyst stage embryo. They can proliferate indefinitely, maintain an undifferentiated state (self-renewal), and differentiate into any cell type (pluripotency). ES cells have an unusual cell cycle structure, consists mainly of S phase cells, a short G1 phase and absence of G1/S checkpoint. Cell division and cell cycle progression are controlled by mechanisms ensuring the accurate transmission of genetic information from generation to generation. Therefore, control of cell cycle is a complicated process, involving several signaling pathways. Although great progress has been made on the molecular mechanisms involved in the regulation of ES cell cycle, many regulatory mechanisms remain unknown. This review summarizes the current knowledge about the molecular mechanisms regulating the cell cycle of ES cells and describes the relationship existing between cell cycle progression and the self-renewal.

  7. Single-cell sequencing in stem cell biology.

    Science.gov (United States)

    Wen, Lu; Tang, Fuchou

    2016-04-15

    Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

  8. Small cell glioblastoma or small cell carcinoma

    DEFF Research Database (Denmark)

    Hilbrandt, Christine; Sathyadas, Sathya; Dahlrot, Rikke H

    2013-01-01

    was admitted to the hospital with left-sided loss of motor function. A MRI revealed a 6 cm tumor in the right temporoparietal area. The histology was consistent with both glioblastoma multiforme (GBM) and small cell lung carcinoma (SCLC) but IHC was suggestive of a SCLC metastasis. PET-CT revealed...

  9. The cell biology of T-dependent B cell activation

    DEFF Research Database (Denmark)

    Owens, T; Zeine, R

    1989-01-01

    The requirement that CD4+ helper T cells recognize antigen in association with class II Major Histocompatibility Complex (MHC) encoded molecules constrains T cells to activation through intercellular interaction. The cell biology of the interactions between CD4+ T cells and antigen-presenting cells...

  10. Retinal stem cells and potential cell transplantation treatments

    Directory of Open Access Journals (Sweden)

    Tai-Chi Lin

    2014-11-01

    Full Text Available The retina, histologically composed of ten delicate layers, is responsible for light perception and relaying electrochemical signals to the secondary neurons and visual cortex. Retinal disease is one of the leading clinical causes of severe vision loss, including age-related macular degeneration, Stargardt's disease, and retinitis pigmentosa. As a result of the discovery of various somatic stem cells, advances in exploring the identities of embryonic stem cells, and the development of induced pluripotent stem cells, cell transplantation treatment for retinal diseases is currently attracting much attention. The sources of stem cells for retinal regeneration include endogenous retinal stem cells (e.g., neuronal stem cells, Müller cells, and retinal stem cells from the ciliary marginal zone and exogenous stem cells (e.g., bone mesenchymal stem cells, adipose-derived stem cells, embryonic stem cells, and induced pluripotent stem cells. The success of cell transplantation treatment depends mainly on the cell source, the timing of cell harvesting, the protocol of cell induction/transplantation, and the microenvironment of the recipient's retina. This review summarizes the different sources of stem cells for regeneration treatment in retinal diseases and surveys the more recent achievements in animal studies and clinical trials. Future directions and challenges in stem cell transplantation are also discussed.

  11. Mesenchymal stem cells: cell biology and potential use in therapy

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Kristiansen, Malthe; Abdallah, Basem M

    2004-01-01

    Mesenchymal stem cells are clonogenic, non-haematopoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages e.g. osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages e.g. neuronal-like cells. Several methods...

  12. Hydrogen and fuel cells

    International Nuclear Information System (INIS)

    2006-06-01

    This road-map proposes by the Group Total aims to inform the public on the hydrogen and fuel cells. It presents the hydrogen technology from the production to the distribution and storage, the issues as motor fuel and fuel cells, the challenge for vehicles applications and the Total commitments in the domain. (A.L.B.)

  13. T-cell costimulation

    DEFF Research Database (Denmark)

    Owens, T

    1996-01-01

    The CD40L molecule expressed by CD4+ regulatory T lymphocytes is known to deliver signals that activate B cells and macrophages. It now appears that CD40L regulates T cells themselves, during both their development and their participation in adaptive immune responses....

  14. Cell phone explosion.

    Science.gov (United States)

    Atreya, Alok; Kanchan, Tanuj; Nepal, Samata; Pandey, Bhuwan Raj

    2016-03-01

    Cell phone explosions and resultant burn injuries are rarely reported in the scientific literature. We report a case of cell phone explosion that occurred when a young male was listening to music while the mobile was plugged in for charging. © The Author(s) 2015.

  15. The Constitution by Cell

    Science.gov (United States)

    Greenhut, Stephanie; Jones, Megan

    2010-01-01

    On their visit to the National Archives Experience in Washington, D.C., students in Jenni Ashley and Gay Brock's U.S. history classes at the Potomac School in McLean, Virginia, participated in a pilot program called "The Constitution by Cell." Armed with their cell phones, a basic understanding of the Constitution, and a willingness to…

  16. MICROBIAL FUEL CELL

    DEFF Research Database (Denmark)

    2008-01-01

    A novel microbial fuel cell construction for the generation of electrical energy. The microbial fuel cell comprises: (i) an anode electrode, (ii) a cathode chamber, said cathode chamber comprising an in let through which an influent enters the cathode chamber, an outlet through which an effluent...

  17. Cell Proliferation in Neuroblastoma

    Science.gov (United States)

    Stafman, Laura L.; Beierle, Elizabeth A.

    2016-01-01

    Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed. PMID:26771642

  18. T-cell count

    Science.gov (United States)

    ... count URL of this page: //medlineplus.gov/ency/article/003516.htm T-cell count To use the sharing features on this ... as hepatitis or mononucleosis Lower than normal T-cell levels may be due to: Acute viral infections Aging Cancer Immune system diseases, such as HIV/AIDS ...

  19. Methanol Fuel Cell

    Science.gov (United States)

    Voecks, G. E.

    1985-01-01

    In proposed fuel-cell system, methanol converted to hydrogen in two places. External fuel processor converts only part of methanol. Remaining methanol converted in fuel cell itself, in reaction at anode. As result, size of fuel processor reduced, system efficiency increased, and cost lowered.

  20. Mesangial cell biology

    International Nuclear Information System (INIS)

    Abboud, Hanna E.

    2012-01-01

    Mesangial cells originate from the metanephric mesenchyme and maintain structural integrity of the glomerular microvascular bed and mesangial matrix homeostasis. In response to metabolic, immunologic or hemodynamic injury, these cells undergo apoptosis or acquire an activated phenotype and undergo hypertrophy, proliferation with excessive production of matrix proteins, growth factors, chemokines and cytokines. These soluble factors exert autocrine and paracrine effects on the cells or on other glomerular cells, respectively. MCs are primary targets of immune-mediated glomerular diseases such as IGA nephropathy or metabolic diseases such as diabetes. MCs may also respond to injury that primarily involves podocytes and endothelial cells or to structural and genetic abnormalities of the glomerular basement membrane. Signal transduction and oxidant stress pathways are activated in MCs and likely represent integrated input from multiple mediators. Such responses are convenient targets for therapeutic intervention. Studies in cultured MCs should be supplemented with in vivo studies as well as examination of freshly isolated cells from normal and diseases glomeruli. In addition to ex vivo morphologic studies in kidney cortex, cells should be studied in their natural environment, isolated glomeruli or even tissue slices. Identification of a specific marker of MCs should help genetic manipulation as well as selective therapeutic targeting of these cells. Identification of biological responses of MCs that are not mediated by the renin–angiotensin system should help development of novel and effective therapeutic strategies to treat diseases characterized by MC pathology.

  1. Mesangial cell biology

    Energy Technology Data Exchange (ETDEWEB)

    Abboud, Hanna E., E-mail: Abboud@uthscsa.edu

    2012-05-15

    Mesangial cells originate from the metanephric mesenchyme and maintain structural integrity of the glomerular microvascular bed and mesangial matrix homeostasis. In response to metabolic, immunologic or hemodynamic injury, these cells undergo apoptosis or acquire an activated phenotype and undergo hypertrophy, proliferation with excessive production of matrix proteins, growth factors, chemokines and cytokines. These soluble factors exert autocrine and paracrine effects on the cells or on other glomerular cells, respectively. MCs are primary targets of immune-mediated glomerular diseases such as IGA nephropathy or metabolic diseases such as diabetes. MCs may also respond to injury that primarily involves podocytes and endothelial cells or to structural and genetic abnormalities of the glomerular basement membrane. Signal transduction and oxidant stress pathways are activated in MCs and likely represent integrated input from multiple mediators. Such responses are convenient targets for therapeutic intervention. Studies in cultured MCs should be supplemented with in vivo studies as well as examination of freshly isolated cells from normal and diseases glomeruli. In addition to ex vivo morphologic studies in kidney cortex, cells should be studied in their natural environment, isolated glomeruli or even tissue slices. Identification of a specific marker of MCs should help genetic manipulation as well as selective therapeutic targeting of these cells. Identification of biological responses of MCs that are not mediated by the renin–angiotensin system should help development of novel and effective therapeutic strategies to treat diseases characterized by MC pathology.

  2. Perovskite Solar Cell

    Indian Academy of Sciences (India)

    Organic–inorganic halide perovskite, a newcomerin the solar cell industry has proved its potential forincreasing efficiency rapidly from 3.8% in 2009 to 22.1% in2016. High efficiency, flexibility, and cell architecture of theemerging hybrid halide perovskite have caught the attentionof researchers and technologists in the field.

  3. Fuel cell sesquicentennial

    Science.gov (United States)

    Cohn, E. M.

    1979-01-01

    The development of fuel cell technology is summarized, and the potential for utility-type fuel cell installations is assessed on the occasion of the 150th anniversary of the construction of the first fuel cell by Sir William Grove. The only functional fuel-cell systems developed to date, the hydrogen-oxygen cells used by NASA, are indicated, and hydrazine and alcohol (methanol) cells are considered. Areas requiring development before the implementation of fuel cells as general purpose utility-type electric generators include catalysts for naturally occurring hydrocarbons or processes for low-cost methanol or hydrazine production, efficient means of scrubbing and enriching air, self-regulating systems, and 15- to 20-fold power density increases. It is argued that although ideas for eliminating certain of the above-mentioned problems have been proposed, fuel-cell systems can never be expected to equal the efficiency, reliability and low cost of conventional power plants, and thus developmental support should be discontinued.

  4. Cystic Granular Cell Ameloblastoma

    OpenAIRE

    Thillaikarasi, Rathnavel; Balaji, Jayaram; Gupta, Bhawna; Ilayarja, Vadivel; Vani, Nandimandalam Venkata; Vidula, Balachander; Saravanan, Balasubramaniam; Ponniah, Irulandy

    2010-01-01

    Ameloblastoma is a locally aggressive benign epithelial odontogenic tumor, while unicystic ameloblastoma is a relatively less aggressive variant. Although rare in unicystic or cystic ameloblastoma, granular cell change in ameloblastoma is a recognized phenomenon. The purpose of the present article is to report a case of cystic granular cell ameloblastoma in 34-year old female.

  5. Cancer stem cells revisited

    NARCIS (Netherlands)

    Batlle, Eduard; Clevers, Hans

    2017-01-01

    The cancer stem cell (CSC) concept was proposed four decades ago, and states that tumor growth, analogous to the renewal of healthy tissues, is fueled by small numbers of dedicated stem cells. It has gradually become clear that many tumors harbor CSCs in dedicated niches, and yet their

  6. Biosensors for Cell Analysis.

    Science.gov (United States)

    Zhou, Qing; Son, Kyungjin; Liu, Ying; Revzin, Alexander

    2015-01-01

    Biosensors first appeared several decades ago to address the need for monitoring physiological parameters such as oxygen or glucose in biological fluids such as blood. More recently, a new wave of biosensors has emerged in order to provide more nuanced and granular information about the composition and function of living cells. Such biosensors exist at the confluence of technology and medicine and often strive to connect cell phenotype or function to physiological or pathophysiological processes. Our review aims to describe some of the key technological aspects of biosensors being developed for cell analysis. The technological aspects covered in our review include biorecognition elements used for biosensor construction, methods for integrating cells with biosensors, approaches to single-cell analysis, and the use of nanostructured biosensors for cell analysis. Our hope is that the spectrum of possibilities for cell analysis described in this review may pique the interest of biomedical scientists and engineers and may spur new collaborations in the area of using biosensors for cell analysis.

  7. Solar cell concentrating system

    International Nuclear Information System (INIS)

    Garg, H.P.; Sharma, V.K.; Agarwal, R.K.

    1986-11-01

    This study reviews fabrication techniques and testing facilities for different solar cells under concentration which have been developed and tested. It is also aimed to examine solar energy concentrators which are prospective candidates for photovoltaic concentrator systems. This may provide an impetus to the scientists working in the area of solar cell technology

  8. Programmed cell death

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The purpose of this conference to provide a multidisciplinary forum for exchange of state-of-the-art information on the role programmed cell death plays in normal development and homeostasis of many organisms. This volume contains abstracts of papers in the following areas: invertebrate development; immunology/neurology; bcl-2 family; biochemistry; programmed cell death in viruses; oncogenesis; vertebrate development; and diseases.

  9. Mammary gland stem cells

    Indian Academy of Sciences (India)

    Mammary gland stem cells (MaSC) have not been identified in spite of extensive research spanning over several decades. This has been primarily due to the complexity of mammary gland structure and its development, cell heterogeneity in the mammary gland and the insufficient knowledge about MaSC markers.

  10. Cell-in-Cell Death Is Not Restricted by Caspase-3 Deficiency in MCF-7 Cells

    Science.gov (United States)

    Wang, Shan; He, Meifang; Li, Linmei; Liang, Zhihua; Zou, Zehong

    2016-01-01

    Purpose Cell-in-cell structures are created by one living cell entering another homotypic or heterotypic living cell, which usually leads to the death of the internalized cell, specifically through caspase-dependent cell death (emperitosis) or lysosome-dependent cell death (entosis). Although entosis has attracted great attention, its occurrence is controversial, because one cell line used in its study (MCF-7) is deficient in caspase-3. Methods We investigated this issue using MCF-7 and A431 cell lines, which often display cell-in-cell invasion, and have different levels of caspase-3 expression. Cell-in-cell death morphology, microstructures, and signaling pathways were compared in the two cell lines. Results Our results confirmed that MCF-7 cells are caspase-3 deficient with a partial deletion in the CASP-3 gene. These cells underwent cell death that lacked typical apoptotic properties after staurosporine treatment, whereas caspase-3-sufficient A431 cells displayed typical apoptosis. The presence of caspase-3 was related neither to the lysosome-dependent nor to the caspase-dependent cell-in-cell death pathway. However, the existence of caspase-3 was associated with a switch from lysosome-dependent cell-in-cell death to the apoptotic cell-in-cell death pathway during entosis. Moreover, cellular hypoxia, mitochondrial swelling, release of cytochrome C, and autophagy were observed in internalized cells during entosis. Conclusion The occurrence of caspase-independent entosis is not a cell-specific process. In addition, entosis actually represents a cellular self-repair system, functioning through autophagy, to degrade damaged mitochondria resulting from cellular hypoxia in cell-in-cell structures. However, sustained autophagy-associated signal activation, without reduction in cellular hypoxia, eventually leads to lysosome-dependent intracellular cell death. PMID:27721872

  11. Normal Untreated Jurkat Cells

    Science.gov (United States)

    2004-01-01

    Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. The objective of the research was to define a way to differentiate between effects due to microgravity and those due to possible stress from non-optimal spaceflight conditions. These Jurkat cells, a human acute T-cell leukemia was obtained to evaluate three types of potential experimental stressors: a) Temperature elevation; b) Serum starvation; and c) Centrifugal force. The data from previous spaceflight experiments showed that actin filaments and cell shape are significantly different for the control. These normal cells serve as the baseline for future spaceflight experiments.

  12. Fuel cells : emerging markets

    International Nuclear Information System (INIS)

    Callaghan Jerram, L.; Adamson, K.A.; Butler, J.; Huleatt-James, N.

    2009-01-01

    This presentation highlighted the findings of the 2009 review of the fuel cell industry and emerging markets as they appeared in Fuel Cell Today (FCT), a benchmark document on global fuel cell activity. Since 2008, the industry has seen a 50 per cent increase in fuel cell systems shipped, from 12,000 units to 18,000 units. Applications have increased for backup power for datacentres, telecoms and light duty vehicles. The 2009 review focused on emerging markets which include non-traditional regions that may experience considerable diffusion of fuel cells within the next 5 year forecast period. The 2009 review included an analysis on the United Arab Emirates, Mexico, Brazil and India and reviewed primary drivers, likely applications for near-term adoption, and government and private sector activity in these regions. The presentation provided a forecast of the global state of the industry in terms of shipments as well as a forecast of countries with emerging markets

  13. Cell manipulation in microfluidics

    International Nuclear Information System (INIS)

    Yun, Hoyoung; Kim, Kisoo; Lee, Won Gu

    2013-01-01

    Recent advances in the lab-on-a-chip field in association with nano/microfluidics have been made for new applications and functionalities to the fields of molecular biology, genetic analysis and proteomics, enabling the expansion of the cell biology field. Specifically, microfluidics has provided promising tools for enhancing cell biological research, since it has the ability to precisely control the cellular environment, to easily mimic heterogeneous cellular environment by multiplexing, and to analyze sub-cellular information by high-contents screening assays at the single-cell level. Various cell manipulation techniques in microfluidics have been developed in accordance with specific objectives and applications. In this review, we examine the latest achievements of cell manipulation techniques in microfluidics by categorizing externally applied forces for manipulation: (i) optical, (ii) magnetic, (iii) electrical, (iv) mechanical and (v) other manipulations. We furthermore focus on history where the manipulation techniques originate and also discuss future perspectives with key examples where available. (topical review)

  14. Solar cell radiation handbook

    Science.gov (United States)

    Tada, H. Y.; Carter, J. R., Jr.; Anspaugh, B. E.; Downing, R. G.

    1982-01-01

    The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  15. Toward sustainable fuel cells

    DEFF Research Database (Denmark)

    Stephens, Ifan; Rossmeisl, Jan; Chorkendorff, Ib

    2016-01-01

    A quarter of humanity's current energy consumption is used for transportation (1). Low-temperature hydrogen fuel cells offer much promise for replacing this colossal use of fossil fuels with renewables; these fuel cells produce negligible emissions and have a mileage and filling time equal to a r......% of the annual automotive vehicle production. Lowering the Pt loading in a fuel cell to a sustainable level requires the reactivity of Pt to be tuned so that it accelerates oxygen reduction more effectively (3). Two reports in this issue address this challenge (4, 5)....... to a regular gasoline car. However, current fuel cells require 0.25 g of platinum (Pt) per kilowatt of power (2) as catalysts to drive the electrode reactions. If the entire global annual production of Pt were devoted to fuel cell vehicles, fewer than 10 million vehicles could be produced each year, a mere 10...

  16. HTPEM Fuel Cell Impedance

    DEFF Research Database (Denmark)

    Vang, Jakob Rabjerg

    As part of the process to create a fossil free Denmark by 2050, there is a need for the development of new energy technologies with higher efficiencies than the current technologies. Fuel cells, that can generate electricity at higher efficiencies than conventional combustion engines, can...... potentially play an important role in the energy system of the future. One of the fuel cell technologies, that receives much attention from the Danish scientific community is high temperature proton exchange membrane (HTPEM) fuel cells based on polybenzimidazole (PBI) with phosphoric acid as proton conductor....... This type of fuel cell operates at higher temperature than comparable fuel cell types and they distinguish themselves by high CO tolerance. Platinum based catalysts have their efficiency reduced by CO and the effect is more pronounced at low temperature. This Ph.D. Thesis investigates this type of fuel...

  17. Cell fusions in mammals

    DEFF Research Database (Denmark)

    Larsson, Lars-Inge; Bjerregaard, Bolette; Talts, Jan Fredrik

    2008-01-01

    Cell fusions are important to fertilization, placentation, development of skeletal muscle and bone, calcium homeostasis and the immune defense system. Additionally, cell fusions participate in tissue repair and may be important to cancer development and progression. A large number of factors appear...... to regulate cell fusions, including receptors and ligands, membrane domain organizing proteins, proteases, signaling molecules and fusogenic proteins forming alpha-helical bundles that bring membranes close together. The syncytin family of proteins represent true fusogens and the founding member, syncytin-1......, has been documented to be involved in fusions between placental trophoblasts, between cancer cells and between cancer cells and host ells. We review the literature with emphasis on the syncytin family and propose that syncytins may represent universal fusogens in primates and rodents, which work...

  18. Cell Control Engineering

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo

    1996-01-01

    The engineering process of creating cell control systems is described, and a Cell Control Engineering (CCE) concept is defined. The purpose is to assist people, representing different disciplines in the organisation, to implement cell controllers by addressing the complexity of having many systems...... in physically and logically different and changing manufacturing environments. The defined CCE concept combines state-of-the-art of commercially available enabling technologies for automation system software development, generic cell control models and guidelines for the complete engineering process....... It facilitates the understanding of the task and structure of cell controllers and uses this knowledge directly in the implementation of the system. By applying generic models CCE facilitates reuse of software components and maintenance of applications. In many enterprises, software makes up an increasing part...

  19. Photovoltaic solar cell

    Science.gov (United States)

    Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

    2015-09-08

    A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

  20. CCL22-specific T Cells

    DEFF Research Database (Denmark)

    Martinenaite, Evelina; Munir Ahmad, Shamaila; Hansen, Morten

    2016-01-01

    Tumor cells and tumor-infiltrating macrophages produce the chemokine CCL22, which attracts regulatory T cells (Tregs) into the tumor microenvironment, decreasing anticancer immunity. Here, we investigated the possibility of targeting CCL22-expressing cells by activating specific T cells. We...... analyzed the CCL22 protein signal sequence, identifying a human leukocyte antigen A2- (HLA-A2-) restricted peptide epitope, which we then used to stimulate peripheral blood mononuclear cells (PMBCs) to expand populations of CCL22-specific T cells in vitro. T cells recognizing an epitope derived from...... the signal-peptide of CCL22 will recognize CCL22-expressing cells even though CCL22 is secreted out of the cell. CCL22-specific T cells recognized and killed CCL22-expressing cancer cells. Furthermore, CCL22-specific T cells lysed acute monocytic leukemia cells in a CCL22 expression-dependent manner. Using...

  1. Time evolution of cell size distributions in dense cell cultures

    Science.gov (United States)

    Khain, Evgeniy

    2015-03-01

    Living cells in a dense system are all in contact with each other. The common assumption is that such cells stop dividing due to a lack of space. Recent experimental observations have shown, however, that cells continue dividing for a while, but other cells in the system must shrink, to allow the newborn cells to grow to a normal size. Due to these ``pressure'' effects, the average cell size dramatically decreases with time, and the dispersion in cell sizes decreases, too. The collective cell behavior becomes even more complex when the system is expanding: cells near the edges are larger and migrate faster, while cells deep inside the colony are smaller and move slower. This exciting experimental data still needs to be described theoretically, incorporating the distribution of cell sizes in the system. We propose a mathematical model for time evolution of cell size distribution both in a closed and open system. The model incorporates cell proliferation, cell growth after division, cell shrinking due to ``pressure'' from other cells, and possible cell detachment from the interface of a growing colony. This research sheds light on physical and biological mechanisms of cell response to a dense environment and on the role of mechanical stresses in determining the distribution of cell sizes in the system.

  2. Oscillating Cell Culture Bioreactor

    Science.gov (United States)

    Freed, Lisa E.; Cheng, Mingyu; Moretti, Matteo G.

    2010-01-01

    To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid

  3. Immunology of Langerhans Cells

    OpenAIRE

    TAMAKI,Kunihiko

    1990-01-01

    Langerhans cells (LC) are antigen-presenting cells residing in the epidermis of the skin. These cells show characteristic dendritic features and are continually repopulated by precursor cells originating in bone marrow. In this review, we will discuss about the characteristics of these cells.

  4. Quantitative imaging of epithelial cell scattering identifies specific inhibitors of cell motility and cell-cell dissociation

    NARCIS (Netherlands)

    Loerke, D.; le Duc, Q.; Blonk, I.; Kerstens, A.; Spanjaard, E.; Machacek, M.; Danuser, G.; de Rooij, J.

    2012-01-01

    The scattering of cultured epithelial cells in response to hepatocyte growth factor (HGF) is a model system that recapitulates key features of metastatic cell behavior in vitro, including disruption of cell-cell adhesions and induction of cell migration. We have developed image analysis tools that

  5. Radioresistance and hypoxic cells

    International Nuclear Information System (INIS)

    Ando, Koichi

    1989-01-01

    Current progress to explore further understanding of tumor hypoxia was reviewed. At subcellular level, hypoxia induces specific proteins, inhibits DNA synthesis as well as initiation of DNA replicon. Radioresistant characteristics of hypoxic cells is questioned in condition where irradiated cells were kept hypoxia during colony formation. Chronically hypoxic cells recovered from the inner layer of V79 multicellular spheroids are more sensitive to radiation than those from the oxic, outer layer. A novel sandwich culture method, which enables to reoxygenate chronic hypoxia, implies that chronically hypoxic cells are less sensitive to radiation after reoxygenation than oxic cells. For in vivo tumor, two types of tumor hypoxia are reported: diffusion-limited, chronic hypoxia and perfusion-limited, acute hypoxia. Evidence supporting the existence of perfusion-limited hypoxia is provided by an elegant method using vital staining and cell sorter. Data of our own laboratory also implies 2 types of tumor hypoxia; fractional hypoxia and incomplete hypoxia. Fractional hypoxia corresponds to a radioresistant tail on a biphasic tumor cell survival curves while tumors with incomplete hypoxia demonstrate only single component with radioresistant characteristics, instead. (author)

  6. Basic cell culture.

    Science.gov (United States)

    Pollard, J W

    1990-01-01

    This article will describe the basic techniques required for successful cell culture. It will also act to introduce some of the other chapters in this volume. It is not intended, as this volume is not, to describe the establishment of a tissue culture laboratory, nor to provide a historical or theoretical survey of cell culture. There are several books that adequately cover these areas, including the now somewhat dated but still valuable volume by Paul (1), the multi-authored Methods in Enzymology volume edited by Jakoby and Pastan (2), and the new edition of Freshney (3). Instead, this chapter's focus will be on the techniques for establishing primary rodent cell cultures from embryos and adult skin, maintaining and subculturing these fibro-blasts and their transformed derivatives, and the isolation of genetically pure strains. The cells described are all derived from Chinese hamsters since, to date, these cells, have proved to be the most useful for somatic cell genetics (4,5). The techniques, however, are generally applicable to most fibroblastic cell types.

  7. Cell line provenance.

    Science.gov (United States)

    Freshney, R Ian

    2002-07-01

    Cultured cell lines have become an extremely valuable resource, both in academic research and in industrial biotechnology. However, their value is frequently compromised by misidentification and undetected microbial contamination. As detailed elsewhere in this volume, the technology, both simple and sophisticated, is available to remedy the problems of misidentification and contamination, given the will to apply it. Combined with proper records of the origin and history of the cell line, assays for authentication and contamination contribute to the provenance of the cell line. Detailed records should start from the initiation or receipt of the cell line, and should incorporate data on the donor as well as the tissue from which the cell line was derived, should continue with details of maintenance, and include any accidental as well as deliberate deviations from normal maintenance. Records should also contain details of authentication and regular checks for contamination. With this information, preferably stored in a database, and suitable backed up, the provenance of the cell line so created makes the cell line a much more valuable resource, fit for validation in industrial applications and more likely to provide reproducible experimental results when disseminated for research in other laboratories.

  8. Llgl1 Connects Cell Polarity with Cell-Cell Adhesion in Embryonic Neural Stem Cells.

    Science.gov (United States)

    Jossin, Yves; Lee, Minhui; Klezovitch, Olga; Kon, Elif; Cossard, Alexia; Lien, Wen-Hui; Fernandez, Tania E; Cooper, Jonathan A; Vasioukhin, Valera

    2017-06-05

    Malformations of the cerebral cortex (MCCs) are devastating developmental disorders. We report here that mice with embryonic neural stem-cell-specific deletion of Llgl1 (Nestin-Cre/Llgl1 fl/fl ), a mammalian ortholog of the Drosophila cell polarity gene lgl, exhibit MCCs resembling severe periventricular heterotopia (PH). Immunohistochemical analyses and live cortical imaging of PH formation revealed that disruption of apical junctional complexes (AJCs) was responsible for PH in Nestin-Cre/Llgl1 fl/fl brains. While it is well known that cell polarity proteins govern the formation of AJCs, the exact mechanisms remain unclear. We show that LLGL1 directly binds to and promotes internalization of N-cadherin, and N-cadherin/LLGL1 interaction is inhibited by atypical protein kinase C-mediated phosphorylation of LLGL1, restricting the accumulation of AJCs to the basolateral-apical boundary. Disruption of the N-cadherin-LLGL1 interaction during cortical development in vivo is sufficient for PH. These findings reveal a mechanism responsible for the physical and functional connection between cell polarity and cell-cell adhesion machineries in mammalian cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Analysis of Cell Cycle Dynamics using Probabilistic Cell Cycle Models

    Science.gov (United States)

    Gurkan-Cavusoglu, Evren; Schupp, Jane E.; Kinsella, Timothy J.; Loparo, Kenneth A.

    2013-01-01

    In this study, we develop asynchronous probabilistic cell cycle models to quantitatively assess the effect of ionizing radiation on a human colon cancer cell line. We use both synchronous and asynchronous cell populations and follow treated cells for up to 2 cell cycle times. The model outputs quantify the changes in cell cycle dynamics following ionizing radiation treatment, principally in the duration of both G1 and G2/M phases. PMID:22254270

  10. Myeloproliferative neoplasm stem cells.

    Science.gov (United States)

    Mead, Adam J; Mullally, Ann

    2017-03-23

    Myeloproliferative neoplasms (MPNs) arise in the hematopoietic stem cell (HSC) compartment as a result of the acquisition of somatic mutations in a single HSC that provides a selective advantage to mutant HSC over normal HSC and promotes myeloid differentiation to engender a myeloproliferative phenotype. This population of somatically mutated HSC, which initiates and sustains MPNs, is termed MPN stem cells. In >95% of cases, mutations that drive the development of an MPN phenotype occur in a mutually exclusive manner in 1 of 3 genes: JAK2 , CALR , or MPL The thrombopoietin receptor, MPL, is the key cytokine receptor in MPN development, and these mutations all activate MPL-JAK-STAT signaling in MPN stem cells. Despite common biological features, MPNs display diverse disease phenotypes as a result of both constitutional and acquired factors that influence MPN stem cells, and likely also as a result of heterogeneity in the HSC in which MPN-initiating mutations arise. As the MPN clone expands, it exerts cell-extrinsic effects on components of the bone marrow niche that can favor the survival and expansion of MPN stem cells over normal HSC, further sustaining and driving malignant hematopoiesis. Although developed as targeted therapies for MPNs, current JAK2 inhibitors do not preferentially target MPN stem cells, and as a result, rarely induce molecular remissions in MPN patients. As the understanding of the molecular mechanisms underlying the clonal dominance of MPN stem cells advances, this will help facilitate the development of therapies that preferentially target MPN stem cells over normal HSC. © 2017 by The American Society of Hematology.

  11. Conversion of primordial germ cells to pluripotent stem cells: methods for cell tracking and culture conditions.

    Science.gov (United States)

    Nagamatsu, Go; Suda, Toshio

    2013-01-01

    Primordial germ cells (PGCs) are unipotent cells committed to germ lineage: PGCs can only differentiate into gametes in vivo. However, upon fertilization, germ cells acquire the capacity to differentiate into all cell types in the body, including germ cells. Therefore, germ cells are thought to have the potential for pluripotency. PGCs can convert to pluripotent stem cells in vitro when cultured under specific conditions that include bFGF, LIF, and the membrane-bound form of SCF (mSCF). Here, the culture conditions which efficiently convert PGCs to pluripotent embryonic germ (EG) cells are described, as well as methods used for identifying pluripotent candidate cells during culture.

  12. PLUTONIUM ELECTROREFINING CELLS

    Science.gov (United States)

    Mullins, L.J. Jr.; Leary, J.A.; Bjorklund, C.W.; Maraman, W.J.

    1963-07-16

    Electrorefining cells for obtaining 99.98% plutonium are described. The cells consist of an impure liquid plutonium anode, a molten PuCl/sub 3/-- alkali or alkaline earth metal chloanode, a molten PuCl/sub 3/-alkali or alkaline earth metal chloride electrolyte, and a nonreactive cathode, all being contained in nonreactive ceramic containers which separate anode from cathode by a short distance and define a gap for the collection of the purified liquid plutonium deposited on the cathode. Important features of these cells are the addition of stirrer blades on the anode lead and a large cathode surface to insure a low current density. (AEC)

  13. Protoparvovirus cell entry

    DEFF Research Database (Denmark)

    Ros, Carlos; Bayat, Nooshin; Wolfisberg, Raphael

    2017-01-01

    and oncolytic activities while being nonpathogenic for humans. The PtPVs invade and replicate within the nucleus making extensive use of the transport, transcription and replication machineries of the host cells. In order to reach the nucleus, PtPVs need to cross over several intracellular barriers and traffic...... through different cell compartments, which limit their infection efficiency. In this review we summarize molecular interactions, capsid structural transitions and hijacking of cellular processes, by which the PtPVs enter and deliver their single-stranded DNA genome into the host cell nucleus...

  14. Quantum dot solar cells

    CERN Document Server

    Wu, Jiang

    2013-01-01

    The third generation of solar cells includes those based on semiconductor quantum dots. This sophisticated technology applies nanotechnology and quantum mechanics theory to enhance the performance of ordinary solar cells. Although a practical application of quantum dot solar cells has yet to be achieved, a large number of theoretical calculations and experimental studies have confirmed the potential for meeting the requirement for ultra-high conversion efficiency. In this book, high-profile scientists have contributed tutorial chapters that outline the methods used in and the results of variou

  15. Solar cell array interconnects

    Science.gov (United States)

    Carey, Paul G.; Thompson, Jesse B.; Colella, Nicolas J.; Williams, Kenneth A.

    1995-01-01

    Electrical interconnects for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb-Sn) no-clean fluxless solder cream, whereby the high breakage of thin (copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb-Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value.

  16. Fuel cell systems

    International Nuclear Information System (INIS)

    Kotevski, Darko

    2003-01-01

    Fuel cell systems are an entirely different approach to the production of electricity than traditional technologies. They are similar to the batteries in that both produce direct current through electrochemical process. There are six types of fuel cells each with a different type of electrolyte, but they all share certain important characteristics: high electrical efficiency, low environmental impact and fuel flexibility. Fuel cells serve a variety of applications: stationary power plants, transport vehicles and portable power. That is why world wide efforts are addressed to improvement of this technology. (Original)

  17. The effect of foxp3-overexpressing Treg cells on non-small cell lung cancer cells.

    Science.gov (United States)

    Peng, Jiangzhou; Yu, Zigang; Xue, Lei; Wang, Jiabin; Li, Jun; Liu, Degang; Yang, Qiang; Lin, Yihui

    2018-04-01

    The aim of the present study was to investigate the novel mechanisms of forkhead box protein P3 (foxp3) in T regulatory (Treg) cells in lung cancer behavior. Treg cells were isolated from the peripheral blood of healthy volunteers and then co‑cultured with 95D cells. A plasmid overexpressing foxp3 was constructed and transfected into Treg cells and an MTS assay was performed to assess cell viability. Flow cytometry was performed to evaluate cell apoptosis and reverse transcription‑quantitative polymerase chain reaction was used to measure mRNA expression. A Transwell assay was used to assess cell invasion. Treg cells were successfully isolated from peripheral blood with purity of 94.26%. Foxp3 expression in Treg cells was significantly increased following co‑culture with 95D cells, while matrix metalloproteinase‑9 expression was upregulated in 95D cells co‑cultured with Treg cells. The apoptosis, invasion and migration abilities of 95D cells were suppressed by co‑culture with Treg cells, whereas the adhesive ability was enhanced. Foxp3 overexpression in Treg cells enhanced the viability and invasiveness of 95D cells, whereas cell adhesion and migration were decreased. The results of the present study demonstrate that the viability and invasiveness of 95D cells are enhanced by foxp3 overexpression in Treg cells, indicating that increased levels of foxp3 in the tumor microenvironment may promote tumor cell growth.

  18. WideCells Group PLC.

    Science.gov (United States)

    Hollands, Peter

    2017-07-01

    WideCells Group PLC (Manchester, UK) is a global stem cell services company with the aim of leading a transformation in cord blood banking and stem cell treatment. There are three key divisions: WideCells, WideAcademy and CellPlan. WideCells provides contract, collaborative and in-house research, and stem cell processing and storage facilities for a wide range of human tissues. WideAcademy, the education and training branch of the WideCells Group, aims to become the thought leader in stem cell technology, influencing and informing the next generation of healthcare professionals working in stem cell technology. CellPlan is a first-of-its-kind medical insurance plan to make stem cell treatment accessible and affordable by providing access to renowned specialists and hospitals globally with financial cover for cord blood transplantation and for participation in clinical trials using cord blood.

  19. Sickle Cell Disease (For Parents)

    Science.gov (United States)

    ... disease, such as hemoglobin SC disease or sickle beta thalassemia . How Is Sickle Cell Disease Diagnosed? Sickle cell ... Test: Hemoglobin Electrophoresis Prenatal Genetic Counseling Genetic Testing Beta Thalassemia Sickle Cell Disease The Truth About Transfusions About ...

  20. Fuel cells: Problems and prospects

    OpenAIRE

    Shukla, AK; Ramesh, KV; Kannan, AM

    1986-01-01

    n recent years, fuel cell technology has advanced significantly. Field trials on certain types of fuel cells have shown promise for electrical use. This article reviews the electrochemistry, problems and prospects of fuel cell systems.

  1. Cell Adhesions: Actin-Based Modules that Mediate Cell-Extracellular Matrix and Cell-Cell Interactions

    Science.gov (United States)

    Bachir, Alexia; Horwitz, Alan Rick; Nelson, W. James; Bianchini, Julie M.

    2018-01-01

    Cell adhesions link cells to the extracellular matrix (ECM) and to each other, and depend on interactions with the actin cytoskeleton. Both cell-ECM and cell-cell adhesion sites contain discrete, yet overlapping functional modules. These modules establish physical association with the actin cytoskeleton, locally modulate actin organization and dynamics, and trigger intracellular signaling pathways. Interplay between these modules generates distinct actin architectures that underlie different stages, types, and functions of cell-ECM and cell-cell adhesions. Actomyosin contractility is required to generate mature, stable adhesions, as well as sense and translate the mechanical properties of the cellular environment to changes in cell organization and behavior. In this chapter we discuss the organization and function of different adhesion modules and how they interact with the actin cytoskeleton. We highlight the molecular mechanisms of mechanotransduction in adhesions, and how adhesion molecules mediate crosstalk between cell-ECM and cell-cell adhesion sites. PMID:28679638

  2. Stem Cell Transplants (For Teens)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Stem Cell Transplants KidsHealth / For Teens / Stem Cell Transplants What's ... Take to Recover? Coping Print What Are Stem Cells? As you probably remember from biology class, every ...

  3. Fuel cell system with interconnect

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhien; Goettler, Richard

    2016-12-20

    The present invention includes an integrated planar, series connected fuel cell system having electrochemical cells electrically connected via interconnects, wherein the anodes of the electrochemical cells are protected against Ni loss and migration via an engineered porous anode barrier layer.

  4. Sertoli-Leydig cell tumor

    Science.gov (United States)

    Sertoli-stromal cell tumor; Arrhenoblastoma; Androblastoma; Ovarian cancer - Sertoli-Leydig cell tumor ... PA: Elsevier Saunders; 2013:chap 13. Prat J. Ovarian sex cord - stromal and steroid cell tumors. In: Mutter GL, Prat J, eds. Pathology of ...

  5. FUEL CELLS IN ENERGY PRODUCTION

    OpenAIRE

    Huang, Xiaoyu

    2011-01-01

    The purpose of this thesis is to study fuel cells. They convert chemical energy directly into electrical energy with high efficiency and low emmission of pollutants. This thesis provides an overview of fuel cell technology.The basic working principle of fuel cells and the basic fuel cell system components are introduced in this thesis. The properties, advantages, disadvantages and applications of six different kinds of fuel cells are introduced. Then the efficiency of each fuel cell is p...

  6. The cell biology of T-dependent B cell activation

    DEFF Research Database (Denmark)

    Owens, T; Zeine, R

    1989-01-01

    The requirement that CD4+ helper T cells recognize antigen in association with class II Major Histocompatibility Complex (MHC) encoded molecules constrains T cells to activation through intercellular interaction. The cell biology of the interactions between CD4+ T cells and antigen-presenting cells...... includes multipoint intermolecular interactions that probably involve aggregation of both polymorphic and monomorphic T cell surface molecules. Such aggregations have been shown in vitro to markedly enhance and, in some cases, induce T cell activation. The production of T-derived lymphokines that have been...... implicated in B cell activation is dependent on the T cell receptor for antigen and its associated CD3 signalling complex. T-dependent help for B cell activation is therefore similarly MHC-restricted and involves T-B intercellular interaction. Recent reports that describe antigen-independent B cell...

  7. Mast cells & Company

    Directory of Open Access Journals (Sweden)

    Friederike eJönsson

    2012-02-01

    Full Text Available Classically, allergy depends on IgE antibodies and on high-affinity IgE receptors expressed by mast cells and basophils. This long accepted IgE/FcεRI/mast cell paradigm, on which the definition of immediate hypersensitivity was based in the Gell and Coomb’s classification, appears too reductionist. Recently accumulated evidence indeed requires that not only IgE but also IgG antibodies, that not only FcεRI but also FcγR of the different types, that not only mast cells and basophils but also neutrophils, monocytes, macrophages, eosinophils, and other myeloid cells by considered as important players in allergy. This view markedly changes our understanding of allergic diseases and, possibly, their treatment.

  8. Acoustics Noise Test Cell

    Data.gov (United States)

    Federal Laboratory Consortium — The Acoustic Noise Test Cell at the NASA/Caltech Jet Propulsion Laboratory (JPL) is located adjacent to the large vibration system; both are located in a class 10K...

  9. Hurthle Cell Cancer

    Science.gov (United States)

    ... breath Hurthle cell cancer Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  10. Schwann Cell Myelination

    Science.gov (United States)

    Salzer, James L.

    2015-01-01

    Myelinated nerve fibers are essential for the rapid propagation of action potentials by saltatory conduction. They form as the result of reciprocal interactions between axons and Schwann cells. Extrinsic signals from the axon, and the extracellular matrix, drive Schwann cells to adopt a myelinating fate, whereas myelination reorganizes the axon for its role in conduction and is essential for its integrity. Here, we review our current understanding of the development, molecular organization, and function of myelinating Schwann cells. Recent findings into the extrinsic signals that drive Schwann cell myelination, their cognate receptors, and the downstream intracellular signaling pathways they activate will be described. Together, these studies provide important new insights into how these pathways converge to activate the transcriptional cascade of myelination and remodel the actin cytoskeleton that is critical for morphogenesis of the myelin sheath. PMID:26054742

  11. Lipocytes (fat cells) (image)

    Science.gov (United States)

    ... to energy output, there is no expansion of fat cells (lipocytes) to accommodate excess. It is only when more calories are taken in than used that the extra fat is stored in the lipocytes and the person ...

  12. Thin Solid Oxide Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material, at least one metal and a catalyst...... material, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same. The present invention also relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous...... cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material and a catalyst material, wherein the electrolyte material is doper zirconia, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same...

  13. Plasma cell leukemia

    DEFF Research Database (Denmark)

    Fernández de Larrea, C; Kyle, R A; Durie, B G M

    2013-01-01

    Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic......-pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds...... regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem cell transplantation if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding...

  14. Conjugated Polymer Solar Cells

    National Research Council Canada - National Science Library

    Paraschuk, Dmitry Y

    2006-01-01

    This report results from a contract tasking Moscow State University as follows: Conjugated polymers are promising materials for many photonics applications, in particular, for photovoltaic and solar cell devices...

  15. Fuel Exhaling Fuel Cell.

    Science.gov (United States)

    Manzoor Bhat, Zahid; Thimmappa, Ravikumar; Devendrachari, Mruthyunjayachari Chattanahalli; Kottaichamy, Alagar Raja; Shafi, Shahid Pottachola; Varhade, Swapnil; Gautam, Manu; Thotiyl, Musthafa Ottakam

    2018-01-18

    State-of-the-art proton exchange membrane fuel cells (PEMFCs) anodically inhale H 2 fuel and cathodically expel water molecules. We show an unprecedented fuel cell concept exhibiting cathodic fuel exhalation capability of anodically inhaled fuel, driven by the neutralization energy on decoupling the direct acid-base chemistry. The fuel exhaling fuel cell delivered a peak power density of 70 mW/cm 2 at a peak current density of 160 mA/cm 2 with a cathodic H 2 output of ∼80 mL in 1 h. We illustrate that the energy benefits from the same fuel stream can at least be doubled by directing it through proposed neutralization electrochemical cell prior to PEMFC in a tandem configuration.

  16. White Blood Cell Disorders

    Science.gov (United States)

    ... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... sample? Analysis of cell surface proteins Chromosomal analysis Cultures for bacteria Determination of the original arrangement of ...

  17. Plasma Cell Disorders

    Science.gov (United States)

    ... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... sample? Analysis of cell surface proteins Chromosomal analysis Cultures for bacteria Determination of the original arrangement of ...

  18. Fuel cells flows study

    International Nuclear Information System (INIS)

    Riva, R.; Bador, B.; Marchand, M.; Lebaigue, O.

    1999-01-01

    Fuel cells are energy converters, which directly and continuously produce electricity from paired oxidation reduction-reactions: In most cases, the reactants are oxygen and hydrogen with water as residue. There are several types of fuel cells using various electrolytes and working at different temperatures. Proton Exchange Membrane Fuel Cells are, in particular, studied in the GESTEAU facility. PEMFC performance is chiefly limited by two thermal-hydraulic phenomena: the drying of membranes and the flooding of gas distributors. Up to now, work has been focused on water flooding of gas channels. This has showed the influence of flow type on the electrical behaviour of the cells and the results obtained have led to proposals for new duct geometries. (authors)

  19. Managing sickle cell disease

    OpenAIRE

    Claster, Susan; Vichinsky, Elliott P

    2003-01-01

    Advances are being made in the management of sickle cell disease for all age groups. This review discusses the progress in amelioration of symptoms, problems unique to particular age groups, and the types of drugs and treatments currently under investigation

  20. Cell Centred Database (CCDB)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Cell Centered Database (CCDB) is a web accessible database for high resolution 2D, 3D and 4D data from light and electron microscopy, including correlated imaging.

  1. Sperm cell proteomics.

    Science.gov (United States)

    Oliva, Rafael; de Mateo, Sara; Estanyol, Josep Maria

    2009-02-01

    The spermatozoon is an accessible cell which can be easily purified and therefore it is particularly well suited for proteomic analysis. It is also an extremely differentiated cell with very marked genetic, cellular, functional and chromatin changes as compared to other cells, and has profound implications for fertility, embryo development and heredity. The recent developments in MS have boosted the potential for identification and study of the sperm proteins. Catalogues of hundreds to thousands of spermatozoan proteins in human and in model species are becoming available setting up the basis for subsequent research, diagnostic applications and the development of specific treatments. The present article reviews the available scientific publications dealing with the composition and function of the sperm cell using an MS proteomic approach.

  2. Beta Cell Breakthroughs

    Science.gov (United States)

    ... enough islets into a patient to achieve insulin independence." The so-called "Edmonton protocol" has some major ... in response to Melton's article in Cell, Baylor College of Medicine researcher Jake Kushner, MD, argued that ...

  3. T-Cell Lymphoma

    Science.gov (United States)

    ... Cell Lymphoma (AITL) is a rare, aggressive type accounting for about seven percent of all patients with ... 100 Buildings Worldwide Will Join the Lymphoma Research Foundation to Light Red to Raise Awareness for Blood ...

  4. Photovoltaic solar cell

    Science.gov (United States)

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

    2013-11-26

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  5. CAM and NK Cells

    Directory of Open Access Journals (Sweden)

    Kazuyoshi Takeda

    2004-01-01

    Full Text Available It is believed that tumor development, outgrowth and metastasis are under the surveillance of the immune system. Although both innate and acquired immune systems play roles, innate immunity is the spearhead against tumors. Recent studies have revealed the critical role of natural killer (NK cells in immune surveillance and that NK cell activity is considerably influenced by various agents, such as environmental factors, stress, foods and drugs. Some of these NK cell stimulants have been used in complementary and alternative medicine (CAM since ancient times. Therefore, the value of CAM should be re-evaluated from this point of view. In this review, we overview the intimate correlation between NK cell functions and CAM agents, and discuss possible underlying mechanisms mediating this. In particular, neuro-immune crosstalk and receptors for CAM agents are the most important and interesting candidates for such mechanisms.

  6. Renal cell carcinoma

    Science.gov (United States)

    ... lining of very small tubes (tubules) in the kidney. ... Kidney cancer; Hypernephroma; Adenocarcinoma of renal cells; Cancer - kidney ... Follow your provider's recommendations in the treatment of kidney disorders, especially those that may require dialysis.

  7. Nanodiamond internalization in cells and the cell uptake mechanism

    International Nuclear Information System (INIS)

    Perevedentseva, E.; Hong, S.-F.; Huang, K.-J.; Chiang, I.-T.; Lee, C.-Y.; Tseng, Y.-T.; Cheng, C.-L.

    2013-01-01

    Cell type-dependent penetration of nanodiamond in living cells is one of the important factors for using nanodiamond as cellular markers/labels, for drug delivery as well as for other biomedical applications. In this work, internalization of 100 nm nanodiamonds by A549 lung human adenocarcinoma cell, Beas-2b non-tumorigenic human bronchial epithelial cell, and HFL-1 fibroblast-like human fetal lung cell is studied and compared. The penetration of nanodiamond into the cells was observed using confocal fluorescence imaging and Raman imaging methods. Visualization of the nanodiamond in cells allows comparison of the internalization for diamond nanoparticles in cancer A549 cell, non-cancer HFL-1, and Beas-2b cells. The dose-dependent and time-dependent behavior of nanodiamond uptake is observed in both cancer as well as non-cancer cells. The mechanism of nanodiamond uptake by cancer and non-cancer cells is analyzed by blocking different pathways. The uptake of nanodiamond in both cancer and non-cancer cells was found predominantly via clathrin-dependent endocytosis. In spite of observed similarity in the uptake mechanism for cancer and non-cancer cells, the nanodiamond uptake for cancer cell quantitatively exceeds the uptake for non-cancer cells, for the studied cell lines. The observed difference in internalization of nanodiamond by cancer and non-cancer cells is discussed

  8. Nanodiamond internalization in cells and the cell uptake mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Perevedentseva, E. [National Dong Hwa University, Department of Physics (China); Hong, S.-F.; Huang, K.-J. [National Dong Hwa University, Department of Life Sciences (China); Chiang, I.-T.; Lee, C.-Y. [National Dong Hwa University, Department of Physics (China); Tseng, Y.-T. [National Dong Hwa University, Department of Life Sciences (China); Cheng, C.-L., E-mail: clcheng@mail.ndhu.edu.tw [National Dong Hwa University, Department of Physics (China)

    2013-08-15

    Cell type-dependent penetration of nanodiamond in living cells is one of the important factors for using nanodiamond as cellular markers/labels, for drug delivery as well as for other biomedical applications. In this work, internalization of 100 nm nanodiamonds by A549 lung human adenocarcinoma cell, Beas-2b non-tumorigenic human bronchial epithelial cell, and HFL-1 fibroblast-like human fetal lung cell is studied and compared. The penetration of nanodiamond into the cells was observed using confocal fluorescence imaging and Raman imaging methods. Visualization of the nanodiamond in cells allows comparison of the internalization for diamond nanoparticles in cancer A549 cell, non-cancer HFL-1, and Beas-2b cells. The dose-dependent and time-dependent behavior of nanodiamond uptake is observed in both cancer as well as non-cancer cells. The mechanism of nanodiamond uptake by cancer and non-cancer cells is analyzed by blocking different pathways. The uptake of nanodiamond in both cancer and non-cancer cells was found predominantly via clathrin-dependent endocytosis. In spite of observed similarity in the uptake mechanism for cancer and non-cancer cells, the nanodiamond uptake for cancer cell quantitatively exceeds the uptake for non-cancer cells, for the studied cell lines. The observed difference in internalization of nanodiamond by cancer and non-cancer cells is discussed.

  9. Liquid fuel cells

    Directory of Open Access Journals (Sweden)

    Grigorii L. Soloveichik

    2014-08-01

    Full Text Available The advantages of liquid fuel cells (LFCs over conventional hydrogen–oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented.

  10. Liquid fuel cells.

    Science.gov (United States)

    Soloveichik, Grigorii L

    2014-01-01

    The advantages of liquid fuel cells (LFCs) over conventional hydrogen-oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented.

  11. Liquid fuel cells

    Science.gov (United States)

    2014-01-01

    Summary The advantages of liquid fuel cells (LFCs) over conventional hydrogen–oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented. PMID:25247123

  12. Syndecans and cell adhesion

    DEFF Research Database (Denmark)

    Couchman, J R; Chen, L; Woods, A

    2001-01-01

    Now that transmembrane signaling through primary cell-matrix receptors, integrins, is being elucidated, attention is turning to how integrin-ligand interactions can be modulated. Syndecans are transmembrane proteoglycans implicated as coreceptors in a variety of physiological processes, including...... cell adhesion, migration, response to growth factors, development, and tumorigenesis. This review will describe this family of proteoglycans in terms of their structures and functions and their signaling in conjunction with integrins, and indicate areas for future research....

  13. Stem cells in psoriasis.

    Science.gov (United States)

    Hou, Ruixia; Li, Junqin; Niu, Xuping; Liu, Ruifeng; Chang, Wenjuan; Zhao, Xincheng; Wang, Qiang; Li, Xinhua; Yin, Guohua; Zhang, Kaiming

    2017-06-01

    Psoriasis is a complex chronic relapsing inflammatory disease. Although the exact mechanism remains unknown, it is commonly accepted that the development of psoriasis is a result of multi-system interactions among the epidermis, dermis, blood vessels, immune system, neuroendocrine system, metabolic system, and hematopoietic system. Many cell types have been confirmed to participate in the pathogenesis of psoriasis. Here, we review the stem cell abnormalities related to psoriasis that have been investigated recently. Copyright © 2016. Published by Elsevier B.V.

  14. Mouse ES cell-derived hematopoietic progenitor cells.

    Science.gov (United States)

    Kim, Eun-Mi; Manzar, Gohar; Zavazava, Nicholas

    2013-01-01

    Future stem cell-based therapies will benefit from the new discoveries being made on pluripotent stem cells such as embryonic stem (ES) cells and induced pluripotent stem (IPS) cells. Understanding the genes regulating pluripotency has opened new opportunities to generate patient-tailored therapies. However, protocols for deriving progenitor cells of therapeutic grade from these pluripotent stem cells are not yet worked out. In particular the potential of these cells in treating diseases when compared to their adult progenitor counterparts is unknown. This is crucial work that needs to be studied in detail because we will need to determine engraftment potential of these cells and their ability for multi-lineage engraftment in the in vivo setting before any clinical applications. The ability of these cells to engraft is dependent on their expression of cell surface markers which guide their homing patterns. In this review, I discuss murine hematopoietic progenitor cells derived from mouse ES cells. Stem cells in the bone marrow are found in the bone marrow niches. Our knowledge of the bone marrow niches is growing and will ultimately lead to improved clinical transplantation of bone marrow cells. We are, however, a long way in appreciating how hematopoietic progenitor cells migrate and populate lymphoid tissues. One of the variables in generating hematopoietic progenitor cells is that different labs use different approaches in generating progenitor cells. In some cases, the ES cell lines used show some variability as well. The cell culture media used by the different investigators highly influence the maturation level of the cells and their homing patterns. Here, mouse ES cell-derived progenitor cells are discussed.

  15. Avian Primordial Germ Cells.

    Science.gov (United States)

    Tagami, Takahiro; Miyahara, Daichi; Nakamura, Yoshiaki

    2017-01-01

    Germ cells transmit genetic information to the next generation through gametogenesis. Primordial germ cells (PGCs) are the first germ-cell population established during development, and are the common origins of both oocytes and spermatogonia. Unlike in other species, PGCs in birds undergo blood circulation to migrate toward the genital ridge, and are one of the major biological properties of avian PGCs. Germ cells enter meiosis and arrest at prophase I during embryogenesis in females, whereas in males they enter mitotic arrest during embryogenesis and enter meiosis only after birth. In chicken, gonadal sex differentiation occurs as early as embryonic day 6, but meiotic initiation of female germ cells starts from a relatively late stage (embryonic day 15.5). Retinoic acid controls meiotic entry in developing chicken gonads through the expressions of retinaldehyde dehydrogenase 2, a major retinoic acid synthesizing enzyme, and cytochrome P450 family 26, subfamily B member 1, a major retinoic acid-degrading enzyme. The other major biological property of avian PGCs is that they can be propagated in vitro for the long term, and this technique is useful for investigating proliferation mechanisms. The main factor involved in chicken PGC proliferation is fibroblast growth factor 2, which activates the signaling of MEK/ERK and thus promotes the cell cycle and anti-apoptosis. Furthermore, the activation of PI3K/Akt signaling is indispensable for the proliferation and survival of chicken PGCs.

  16. Hematopoietic stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Eleftheria Hatzimichael

    2010-08-01

    Full Text Available Eleftheria Hatzimichael1, Mark Tuthill21Department of Haematology, Medical School of Ioannina, University of Ioannina, Ioannina, Greece; 2Department of Medical Oncology, Hammersmith Hospital, Imperial College National Health Service Trust, London, UKAbstract: More than 25,000 hematopoietic stem cell transplantations (HSCTs are performed each year for the treatment of lymphoma, leukemia, immune-deficiency illnesses, congenital metabolic defects, hemoglobinopathies, and myelodysplastic and myeloproliferative syndromes. Before transplantation, patients receive intensive myeloablative chemoradiotherapy followed by stem cell “rescue.” Autologous HSCT is performed using the patient’s own hematopoietic stem cells, which are harvested before transplantation and reinfused after myeloablation. Allogeneic HSCT uses human leukocyte antigen (HLA-matched stem cells derived from a donor. Survival after allogeneic transplantation depends on donor–recipient matching, the graft-versus-host response, and the development of a graft versus leukemia effect. This article reviews the biology of stem cells, clinical efficacy of HSCT, transplantation procedures, and potential complications.Keywords: hematopoietic stem cell transplantation, complications

  17. Live-cell imaging.

    Science.gov (United States)

    Cole, Richard

    2014-01-01

    It would be hard to argue that live-cell imaging has not changed our view of biology. The past 10 years have seen an explosion of interest in imaging cellular processes, down to the molecular level. There are now many advanced techniques being applied to live cell imaging. However, cellular health is often under appreciated. For many researchers, if the cell at the end of the experiment has not gone into apoptosis or is blebbed beyond recognition, than all is well. This is simply incorrect. There are many factors that need to be considered when performing live-cell imaging in order to maintain cellular health such as: imaging modality, media, temperature, humidity, PH, osmolality, and photon dose. The wavelength of illuminating light, and the total photon dose that the cells are exposed to, comprise two of the most important and controllable parameters of live-cell imaging. The lowest photon dose that achieves a measureable metric for the experimental question should be used, not the dose that produces cover photo quality images. This is paramount to ensure that the cellular processes being investigated are in their in vitro state and not shifted to an alternate pathway due to environmental stress. The timing of the mitosis is an ideal canary in the gold mine, in that any stress induced from the imaging will result in the increased length of mitosis, thus providing a control model for the current imagining conditions.

  18. Fiscal 1993 achievement report on next-generation industrial structure technology (Advanced materials for extreme environments - Development of methane fueled aeroengine); 1993 nendo chotaikankyosei senshin zairyo no kenkyu kaihatsu seika hokokusho. Methane nenryo kokukiyo engine no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    Efforts were exerted to develop advanced materials for use under extreme environments, which were intermetallic compounds and fiber reinforced intermetallic compound composite materials excellent in heat resistance, specific strength, oxidation resistance, or the like. For the development of intermetallic compounds, efforts were made to develop Ti-Al-X (X=metal) high specific strength intermetallic compounds and Nb-Al-X (X=metal) high melting point intermetallic compounds. Ternary phase diagrams were prepared and the effect of added elements on basic characteristics was investigated. Basics of element technologies (texture control, melting, casting, and isothermal rolling) for manufacturing panel materials were studied and, in the case of Ti-Al-X systems, Ti-Al thin panels were fabricated. In the case of Nb-Al-X systems, items were experimentally fabricated by casting in an effort to study precision casting technology optimization. For the development of composite materials, efforts were made to develop SiC based and SiMC (M=metal) based fibers, and studies were carried out to complex them with Ti-Al based matrices. (NEDO)

  19. Report for fiscal 1998 on results of research and development of silicon-based polymeric material. Material research for the liquid methane fueled aircraft engine; 1998 nendo keisokei kobunshi zairyo no kenkyu kaihatsu seika hokokusho. Methane nenryo kokukiyo engine kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Research was conducted for the purpose of establishing basic technology concerning molecular design, synthesis, material formation, and evaluation of silicon-based polymers which are expected to provide superior electronic/optical functions, high heat/combustion resistance and dynamic properties. The research subjects were such as following: research and development of silicon-based polymeric materials with sea-island microstructures; research and development of silicon-based polymeric materials with sea-island microstructures; research and development on IPN formation with silicon-based polymers; research and development of hybrid silicon polymers with organometallic compounds; research and development of silicon containing polymer materials with ring structures; general committee for investigation and research; the optimized low-temperature Wurtz synthesis and modification of polysilanes; study of unsaturated and hypercoordinate organosilicon compounds; basic studies on the synthesis and properties of silicon-based high polymers; studies of new monomer-synthesis and their polymerization reaction; studies on new method of preparation and functionalization of polysilanes; novel applications of silicon-based polymers in imaging devices for information display, memory, and recordings; and molecular design of silicon-containing {pi}-conjugated and {sigma}-conjugated compounds. (NEDO)

  20. Fiscal 1997 survey report. Basic survey on trends of waste use type production facilities and waste fuel production facilities; 1997 nendo chosa hokokusho. Haikibutsu riyogata seizo shisetsu oyobi haikibutsu nenryo seizo shisetsu doko kiso chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    This survey was made to obtain the basic data for future spread and promotion of No.6 type (waste use type production facilities) and No.7 type (waste fuel production facilities) which were added to the objects having been subsidized since fiscal 1997 under `the environmental harmony type energy community project.` In the former, the kiln in the cement industry and the blast furnace in the steel industry can be extremely large places to receive waste plastic since the facilities are distributed in every area and the treatment capacity is large. However, the effective collection, transportation and sorting of large quantity of waste plastic, especially the problem of removal of vinyl chloride, is a big bottleneck. As to the use of waste plastic using gasification technology, there are no actual results on the commercial basis. That is, however, appropriate for treatment of the waste difficult in treatment, and can be expected of the usage in the chemical industry. In the latter, in the facilities using industrial waste raw materials as fuel, solidification and liquefaction are both operated on a commercial basis. In relation to the solidification and use as fuel of general waste, the treatment of combustion ash is preventing the expansion of use of waste in the industrial field because of a large quantity of chlorine included in the products. 92 refs., 54 figs., 35 tabs.

  1. FY 1999 report on the model project on the effective utilization of waste-base biomass fuels. Basic survey for the feasibility; 1999 nendo haikibutsukei biomass nenryo yuko riyo model jigyo jisshi kanosei kiso chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Survey on the waste biomass was conducted for Thailand, Malaysia, Indonesia, Vietnam, Laos, Nepal, Butan, Myanmar and Cambodia to study feasibility of the project for the concrete utilization of biomass resources. In Thailand, it is expected to construct large-scale model plants for biomass resources such as rice hulls, bagasse, wood waste and oil palm. In Malaysia, expected are the cogeneration at 5MW class palm oil plant, large-scale power plant using wood waste, plant using the biomass from waste palm oil, etc. In Indonesia, there is a great potentiality, but it is necessary to handle it carefully in consideration of the unstable situation of the society. In Vietnam, the detailed survey of feasibility is needed on the project for efficiency heightening at state-run plants, the assumed national plants (recommended by the government), etc. In Laos, small-scale power generation using the forestry waste such as sawdust is expected. (NEDO)

  2. Research on the general analytical method of fossil fuel cycle from a viewpoint of the global environment. 3; Chikyu kankyo kara mita sogoteki kaseki nenryo cycle bunseki hyoka shuho no chosa. 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    The general analysis/assessment method of a fossil fuel cycle was studied. Seven kinds of power generation plants such as LNG cycle and coal cycle ones, and four kinds of transport and treatment systems of recovered CO2 such as ocean and underground systems were studied as case studies on life cycle analysis. As data necessary for life cycle analysis, the database was constructed which stores the facilities and operational energy required for a total energy system from mining of fossil fuel to treatment of recovered CO2, and the quantity of environmental waste such as CO2 emission. As a result, the decrease rate of energy balance defined as ratio of input energy to power plant output was estimated to be 14-43% and 20-60% in LNG cycle and coal cycle, respectively. Even if the recovery rate of CO2 in power plants reached 80-90%, reduction of total CO2 emission was limited to only 20-40% because of CO2 emission during mining, liquefaction and transport of fuel. 168 refs., 48 figs., 102 tabs.

  3. Proceedings of the Joint Meeting of The Fuel Society of Japan (1991). 28th Coal Science Conference/91st Coke Meeting; (Sha) nenryo kyokai godo taikai happyo ronbunshu (1991). Dai 28 kai sekitan kagaku kaigi dai 91 kai cokes tokubetsukai

    Energy Technology Data Exchange (ETDEWEB)

    1991-11-07

    Relating to coke, studies are made on the rapid coke production method, oven investigation during carbonization, and operational management/control. As to coal science, studies are mainly on the brown coal two-stage liquefaction (BCL) method, and data on the pilot plant and PSU are reported. Concerning bituminous coal liquefaction, PSU data mostly including the NEDOL process, and characteristics of liquefaction residue and its effective utilization by thermal decomposition are reported. Regarding the liquefaction mechanism, an experimentally extensive study on catalyst, solvent and reaction conditions is made using model materials and coal itself on the bench scale and also in the pilot plant. Engineering subjects on residue, solvent deashing, scale attachment and coprocessing are also reported. Relations of decomposition process to coal chemical structure changes and reaction conditions are investigated. As to coal gasification, studies, which are not many, are conducted on material balance, heat balance, and image characteristics of char for gasification and factors controlling reactivity.

  4. Spray characteristics of dimethyl ether (D.M.E.) as on alternative fuel for diesel engine; Daitai diesel nenryo to shite no dimethyl ether (D.M.E.) no funmu tokusei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Wakai, K.; Nishida, K.; Yoshizaki, T.; Hiroyasu, H. [Hiroshima University, Hiroshima (Japan)

    1997-10-01

    D.M.E. which was paid attention to as on alternative fuel for a diesel engine, was injected by using Bosch type injection pump and a hole nozzle into a high pressure and high temperature vessel. The spray was observed by using schlieren photography. Spray characteristics, such as, the tip penetration, the cone angle and the volume of the spray were and were compared with a diesel fuel spray. The following thing, and so on were found out as a results. The spray angle of the DME spray of atmosphere pressure Pa=0.1Mpa spreads out large in comparison with the diesel fuel spray, and the way of the change by the pressure is contrary to the case of the diesel fuel spray. 3 refs., 6 figs., 1 tab.

  5. Three-dimensional analysis of internal flow characteristics in the injection nozzle tip of direct-injection diesel engines; Sanjigen suchi kaiseki ni yoru DI diesel kikan no nenryo funsha nozzle nai ryudo tokusei no kaimei

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, H.; Matsui, Y.; Kimura, S. [Nissan Motor Co. Ltd. Tokyo (Japan)

    1997-10-01

    To reduce the exhaust emissions and fuel consumption of direct-injection diesel engines, it is essential to optimize the fuel injection equipment closely related to combustion and emission characteristics. In this study, three-dimensional computation has been applied to investigate the effects of the injection nozzle specifications (e.g., sac volume, round shape at the inlet of the nozzle hole) and needle tip deviation on internal flow characteristics. The computational results revealed that the effects of the nozzle specifications and needle tip deviation with a smaller needle lift on internal flow characteristics and a general approach to optimize the injection nozzle specifications were obtained. 3 refs., 10 figs., 1 tab.

  6. Study of a fuel injection quantity sensor in diesel engine. Part 3. Experimental evaluation of the improved type micro turbine sensor; Diesel kikan ni okeru nenryo funsharyo sensor no kenkyu. 3. Funsharyo keisoku no seido kojo ni kansuru jikken hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Maehara, H.; Iwasaki, T.; Kobayashi, T. [Zexel Corp., Tokyo (Japan)

    1997-10-01

    A Micro Turbine Sensor has been developed to measure fuel injection quantity and injection rate. Previous reports described results of experiments on the MTS which were carried out under steady and unsteady flow conditions. The MTS has been improved in shape of a holder tip and a detecting procedure for rotating speed of a turbine. As a result revolution speed of the turbine increased 18% over the conventional type holder under steady flow condition. Furthermore the measurement resolution of the MTS came up to about 2(mm{sup 3}/pulse) at 20(mm{sup 3}/stroke) under intermittent spray conditions using fuel injection pump. 11 refs., 11 figs., 1 tab.

  7. Injection and spray characteristics of a variable orifice nozzle applied the jerk type fuel injection pump for DI diesel engine; Jerk shiki nenryo funsha pump wo mochiita kahen funko nozzle no funsha funmu tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, T.; Matsui, K.; Iwasaki, T.; Kobayashi, T. [Zexel Corp., Tokyo (Japan); Matsumoto, Y. [The University of Tokyo, Tokyo (Japan)

    1997-10-01

    A Variable Orifice Nozzle (VON) by changing a cross-sectional area of the nozzle injection hole, for improving a rate of injection and injection duration, has been developed to study its injection and spray characteristics. The nozzle geometry was optimized to analyze a nozzle internal flow by computational method. Results show that, injection and spray pattern responded to the nozzle orifice cross-sectional area which is changing larger to smaller in the part load range. This results suggest to contribute a combustion improvement which decreasing NOx and soot. 14 refs., 10 figs.

  8. Dynamic programming for reduction of fuel consumption in a photovoltaic/wind/diesel generating system; Doteki keikakuho ni yoru taiyoko/furyoku/diesel hatsuden system no nenryo shohiryo no sakugen

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, K.; Kenmoku, Y.; Sakakibara, T. [Toyohashi University of Technology, Aichi (Japan); Nakagawa, S. [Maizuru National College of Technology, Kyoto (Japan); Kawamoto, T. [Shizuoka University, Shizuoka (Japan)

    1997-11-25

    Dynamic programming is employed in the study of the operation of the diesel engine in a photovoltaic/wind-force/diesel-engine power generating system, which aims at reduction in the system fuel consumption and at determining an optimum system constitution. The parameters set in this system are the photovoltaic/wind-force supply rate, photovoltaic/wind-force power generation ratio, and battery capacity. An island in Ise Bay, with an annual load power of approximately 1.59-million kWh and mean daily load power of approximately 4336kWh is assumed as the location for the system. Observation data of Ommaezaki Weather Station are utilized for the calculation of the amount of photovoltaic/wind-force power generation. It is found as the result that the fuel consumption of the diesel engine in this system decreases to 82-84% when the natural energy supply rate is 20%. It is also found that the fuel consumption of the system records the minimum at a photovoltaic/wind-force ratio of 60/40, irrespective of the battery capacity or natural energy supply rate, and this ratio is the optimum ratio. 3 refs., 9 figs., 1 tab.

  9. Microbial Cell Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Doktycz, Mitchel John [ORNL; Sullivan, Claretta [Eastern Virginia Medical School; Mortensen, Ninell P [ORNL; Allison, David P [ORNL

    2011-01-01

    Atomic force microscopy (AFM) is finding increasing application in a variety of fields including microbiology. Until the emergence of AFM, techniques for ivnestigating processes in single microbes were limited. From a biologist's perspective, the fact that AFM can be used to generate high-resolution images in buffers or media is its most appealing feature as live-cell imaging can be pursued. Imaging living cells by AFM allows dynamic biological events to be studied, at the nanoscale, in real time. Few areas of biological research have as much to gain as microbiology from the application of AFM. Whereas the scale of microbes places them near the limit of resolution for light microscopy. AFM is well suited for the study of structures on the order of a micron or less. Although electron microscopy techniques have been the standard for high-resolution imaging of microbes, AFM is quickly gaining favor for several reasons. First, fixatives that impair biological activity are not required. Second, AFM is capable of detecting forces in the pN range, and precise control of the force applied to the cantilever can be maintained. This combination facilitates the evaluation of physical characteristics of microbes. Third, rather than yielding the composite, statistical average of cell populations, as is the case with many biochemical assays, the behavior of single cells can be monitored. Despite the potential of AFM in microbiology, there are several limitations that must be considered. For example, the time required to record an image allows for the study of gross events such as cell division or membrane degradation from an antibiotic but precludes the evaluation of biological reactions and events that happen in just fractions of a second. Additionally, the AFM is a topographical tool and is restricted to imaging surfaces. Therefore, it cannot be used to look inside cells as with opticla and transmission electron microscopes. other practical considerations are the

  10. Microfluidics for single cell analysis

    DEFF Research Database (Denmark)

    Jensen, Marie Pødenphant

    Isolation and manipulation of single cells have gained an increasing interest from researchers because of the heterogeneity of cells from the same cell culture. Single cell analysis can ensure a better understanding of differences between individual cells and potentially solve a variety of clinical...... problems. In this thesis lab on a chip systems for rare single cell analysis are investigated. The focus was to develop a commercial, disposable device for circulating tumour cell (CTC) analysis. Such a device must be able to separate rare cells from blood samples and subsequently capture the specific...... cells, and simultaneously be fabricated and operated at low costs and be user-friendly. These challenges were addressed through development of two microfluidic devices, one for rare cell isolation based on pinched flow fractionation (PFF) and one for single cell capture based on hydrodynamic trapping...

  11. Germline and Pluripotent Stem Cells.

    Science.gov (United States)

    Reik, Wolf; Surani, M Azim

    2015-11-02

    Epigenetic mechanisms play an essential role in the germline and imprinting cycle. Germ cells show extensive epigenetic programming in preparation for the generation of the totipotent state, which in turn leads to the establishment of pluripotent cells in blastocysts. The latter are the cells from which pluripotent embryonic stem cells are derived and maintained in culture. Following blastocyst implantation, postimplantation epiblast cells develop, which give rise to all somatic cells as well as primordial germ cells, the precursors of sperm and eggs. Pluripotent stem cells in culture can be induced to undergo differentiation into somatic cells and germ cells in culture. Understanding the natural cycles of epigenetic reprogramming that occur in the germline will allow the generation of better and more versatile stem cells for both therapeutic and research purposes. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

  12. Anti-regulatory T cells

    DEFF Research Database (Denmark)

    Andersen, Mads Hald

    2017-01-01

    Our initial understanding of immune-regulatory cells was based on the discovery of suppressor cells that assure peripheral T-cell tolerance and promote immune homeostasis. Research has particularly focused on the importance of regulatory T cells (Tregs) for immune modulation, e.g. directing host...... responses to tumours or inhibiting autoimmunity development. However, recent studies report the discovery of self-reactive pro-inflammatory T cells—termed anti-regulatory T cells (anti-Tregs)—that target immune-suppressive cells. Thus, regulatory cells can now be defined as both cells that suppress immune...... reactions as well as effector cells that counteract the effects of suppressor cells and support immune reactions. Self-reactive anti-Tregs have been described that specifically recognize human leukocyte antigen-restricted epitopes derived from proteins that are normally expressed by regulatory immune cells...

  13. Bidirectional regulation between B cells and T cells

    NARCIS (Netherlands)

    Margry, B.

    2014-01-01

    B cells were often thought of as simple precursors of end-stage effector cells that are merely in charge of antibody production. Research in the last decades has shown that B cells possess important other roles as well, including their involvement in the regulation and functioning of T cell-mediated

  14. Mesenchymal stem cells differentiate into hepatocyte-like cells ...

    African Journals Online (AJOL)

    ... failure was induced in vitro into hepatocytes-like cells by three cell culture media (serum-free medium (group 1), auto serum-containing medium (group 2) and medium supplemented with fetal bovine serum (FBS) (group 3)). Cell morphology, cell growth curve, amount of urea and glycogen and mRNA expressions of ALB, ...

  15. A fine romance: T follicular helper cells and B cells.

    Science.gov (United States)

    King, Cecile

    2011-06-24

    T follicular helper (Tfh) cells help B cells to generate affinity-matured antibodies. Three papers in this issue of Immunity (Choi et al., 2011; Kerfoot et al., 2011; Kitano et al., 2011) provide information about the reciprocal relationship between B cells and Tfh cells. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Establishment of cell lines with rat spermatogonial stem cell characteristics

    NARCIS (Netherlands)

    van Pelt, Ans M. M.; Roepers-Gajadien, Hermien L.; Gademan, Iris S.; Creemers, Laura B.; de Rooij, Dirk G.; van Dissel-Emiliani, Federica M. F.

    2002-01-01

    Spermatogonial cell lines were established by transfecting a mixed population of purified rat A(s) (stem cells), A(pr) and A(al) spermatogonia with SV40 large T antigen. Two cell lines were characterized and found to express Hsp90alpha and oct-4, specific markers for germ cells and A spermatogonia,

  17. Optimizing cell viability in droplet-based cell deposition

    NARCIS (Netherlands)

    Hendriks, Jan; Visser, C.W.; Henke, S.J.; Leijten, Jeroen Christianus Hermanus; Saris, Daniël B.F.; Sun, Chao; Lohse, Detlef; Karperien, Hermanus Bernardus Johannes

    2015-01-01

    Biofabrication commonly involves the use of liquid droplets to transport cells to the printed structure. However, the viability of the cells after impact is poorly controlled and understood, hampering applications including cell spraying, inkjet bioprinting, and laser-assisted cell transfer. Here,

  18. Fuel Cell Electrodes for Hydrogen-Air Fuel Cell Assemblies.

    Science.gov (United States)

    The report describes the design and evaluation of a hydrogen-air fuel cell module for use in a portable hydrid fuel cell -battery system. The fuel ... cell module consists of a stack of 20 single assemblies. Each assembly contains 2 electrically independent cells with a common electrolyte compartment

  19. Cell supermarket: Adipose tissue as a source of stem cells

    Science.gov (United States)

    Adipose tissue is derived from numerous sources, and in recent years has been shown to provide numerous cells from what seemingly was a population of homogeneous adipocytes. Considering the types of cells that adipose tissue-derived cells may form, these cells may be useful in a variety of clinical ...

  20. Stabilization Of Apoptotic Cells: Generation Of Zombie Cells

    Directory of Open Access Journals (Sweden)

    José A. Sánchez Alcázar

    2015-08-01

    Stabilization of apoptotic cells can be used for reliable detection and quantification of apoptosis in cultured cells and may allow a safer administration of apoptotic cells in clinical applications. Furthermore, it opens new avenues in the functional reconstruction of apoptotic cells for longer preservation.

  1. An Effective Feedback Loop between Cell-Cell Contact Duration and Morphogen Signaling Determines Cell Fate.

    Science.gov (United States)

    Barone, Vanessa; Lang, Moritz; Krens, S F Gabriel; Pradhan, Saurabh J; Shamipour, Shayan; Sako, Keisuke; Sikora, Mateusz; Guet, Călin C; Heisenberg, Carl-Philipp

    2017-10-23

    Cell-cell contact formation constitutes an essential step in evolution, leading to the differentiation of specialized cell types. However, remarkably little is known about whether and how the interplay between contact formation and fate specification affects development. Here, we identify a positive feedback loop between cell-cell contact duration, morphogen signaling, and mesendoderm cell-fate specification during zebrafish gastrulation. We show that long-lasting cell-cell contacts enhance the competence of prechordal plate (ppl) progenitor cells to respond to Nodal signaling, required for ppl cell-fate specification. We further show that Nodal signaling promotes ppl cell-cell contact duration, generating a positive feedback loop between ppl cell-cell contact duration and cell-fate specification. Finally, by combining mathematical modeling and experimentation, we show that this feedback determines whether anterior axial mesendoderm cells become ppl or, instead, turn into endoderm. Thus, the interdependent activities of cell-cell signaling and contact formation control fate diversification within the developing embryo. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. β-Cell regeneration through the transdifferentiation of pancreatic cells: Pancreatic progenitor cells in the pancreas.

    Science.gov (United States)

    Kim, Hyo-Sup; Lee, Moon-Kyu

    2016-05-01

    Pancreatic progenitor cell research has been in the spotlight, as these cells have the potential to replace pancreatic β-cells for the treatment of type 1 and 2 diabetic patients with the absence or reduction of pancreatic β-cells. During the past few decades, the successful treatment of diabetes through transplantation of the whole pancreas or isolated islets has nearly been achieved. However, novel sources of pancreatic islets or insulin-producing cells are required to provide sufficient amounts of donor tissues. To overcome this limitation, the use of pancreatic progenitor cells is gaining more attention. In particular, pancreatic exocrine cells, such as duct epithelial cells and acinar cells, are attractive candidates for β-cell regeneration because of their differentiation potential and pancreatic lineage characteristics. It has been assumed that β-cell neogenesis from pancreatic progenitor cells could occur in pancreatic ducts in the postnatal stage. Several studies have shown that insulin-producing cells can arise in the duct tissue of the adult pancreas. Acinar cells also might have the potential to differentiate into insulin-producing cells. The present review summarizes recent progress in research on the transdifferentiation of pancreatic exocrine cells into insulin-producing cells, especially duct and acinar cells.

  3. Asymmetric cell division during T cell development controls downstream fate

    Science.gov (United States)

    Pham, Kim; Shimoni, Raz; Charnley, Mirren; Ludford-Menting, Mandy J.; Hawkins, Edwin D.; Ramsbottom, Kelly; Oliaro, Jane; Izon, David; Ting, Stephen B.; Reynolds, Joseph; Lythe, Grant; Molina-Paris, Carmen; Melichar, Heather; Robey, Ellen; Humbert, Patrick O.; Gu, Min

    2015-01-01

    During mammalian T cell development, the requirement for expansion of many individual T cell clones, rather than merely expansion of the entire T cell population, suggests a possible role for asymmetric cell division (ACD). We show that ACD of developing T cells controls cell fate through differential inheritance of cell fate determinants Numb and α-Adaptin. ACD occurs specifically during the β-selection stage of T cell development, and subsequent divisions are predominantly symmetric. ACD is controlled by interaction with stromal cells and chemokine receptor signaling and uses a conserved network of polarity regulators. The disruption of polarity by deletion of the polarity regulator, Scribble, or the altered inheritance of fate determinants impacts subsequent fate decisions to influence the numbers of DN4 cells arising after the β-selection checkpoint. These findings indicate that ACD enables the thymic microenvironment to orchestrate fate decisions related to differentiation and self-renewal. PMID:26370500

  4. Plant cell wall polysaccharide analysis during cell elongation

    DEFF Research Database (Denmark)

    Guo, Xiaoyuan

    Plant cell walls are complex structures whose composition and architecture are important to various cellular activities. Plant cell elongation requires a high level of rearrangement of the cell wall polymers to enable cell expansion. However, the cell wall polysaccharides dynamics during plant cell...... elongation is poorly understood. This PhD project aims to elucidate the cell wall compositional and structural change during cell elongation by using Comprehensive Microarray Polymer Profiling (CoMPP), microscopic techniques and molecular modifications of cell wall polysaccharide. Developing cotton fibre......, pea and Arabidopsis thaliana were selected as research models to investigate different types of cell elongation, developmental elongation and tropism elongation. A set of comprehensive analysis covering 4 cotton species and 11 time points suggests that non-cellulosic polysaccharides contribute...

  5. Reprogramming of retinoblastoma cancer cells into cancer stem cells.

    Science.gov (United States)

    Yue, Fengming; Hirashima, Kanji; Tomotsune, Daihachiro; Takizawa-Shirasawa, Sakiko; Yokoyama, Tadayuki; Sasaki, Katsunori

    2017-01-22

    Retinoblastoma is the most common intraocular malignancy in pediatric patients. It develops rapidly in the retina and can be fatal if not treated promptly. It has been proposed that a small population of cancer cells, termed cancer stem cells (CSCs), initiate tumorigenesis from immature tissue stem cells or progenitor cells. Reprogramming technology, which can convert mature cells into pluripotent stem cells (iPS), provides the possibility of transducing malignant cancer cells back to CSCs, a type of early stage of cancer. We herein took advantage of reprogramming technology to induce CSCs from retinoblastoma cancer cells. In the present study, the 4 Yamanaka transcription factors, Oct4, Sox2, Klf4 and c-myc, were transduced into retinoblastoma cells (Rbc51). iPS-like colonies were observed 15 days after transduction and showed significantly enhanced CSC properties. The gene and protein expression levels of pluripotent stem cell markers (Tra-1-60, Oct4, Nanog) and cancer stem cell markers (CD133, CD44) were up-regulated in transduced Rbc51 cells compared to control cells. Moreover, iPS-like CSCs could be sorted using the Magnetic-activated cell sorting (MACS) method. A sphere formation assay demonstrated spheroid formation in transduced Rbc51 cells cultured in serum free media, and these spheroids could be differentiated into Pax6-, Nestin-positive neural progenitors and rhodopsin- and recoverin-positive mature retinal cells. The cell viability after 5-Fu exposure was higher in transduced Rbc51 cells. In conclusion, CSCs were generated from retinoblastoma cancer cells using reprogramming technology. Our novel method can generate CSCs, the study of which can lead to better understanding of cancer-specific initiation, cancer epigenetics, and the overlapping mechanisms of cancer development and pluripotent stem cell behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Cell proliferation alterations in Chlorella cells under stress conditions

    International Nuclear Information System (INIS)

    Rioboo, Carmen; O'Connor, Jose Enrique; Prado, Raquel; Herrero, Concepcion; Cid, Angeles

    2009-01-01

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  7. Cell proliferation alterations in Chlorella cells under stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rioboo, Carmen [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); O' Connor, Jose Enrique [Laboratorio de Citomica, Unidad Mixta de Investigacion CIPF-UVEG, Centro de Investigacion Principe Felipe, Avda. Autopista del Saler, 16, 46013 Valencia (Spain); Prado, Raquel; Herrero, Concepcion [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); Cid, Angeles, E-mail: cid@udc.es [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain)

    2009-09-14

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  8. Basal cell carcinoma: pathophysiology.

    Science.gov (United States)

    Sehgal, Virendra N; Chatterjee, Kingshuk; Pandhi, Deepika; Khurana, Ananta

    2014-01-01

    Basal cell carcinoma (BCC) is the most common skin cancer in humans, which typically appears over the sun-exposed skin as a slow-growing, locally invasive lesion that rarely metastasizes. Although the exact etiology of BCC is unknown, there exists a well-established relationship between BCC and the pilo-sebaceous unit, and it is currently thought to originate from pluri-potential cells in the basal layer of the epidermis or the follicle. The patched/hedgehog intracellular signaling pathway plays a central role in both sporadic BCCs and nevoid BCC syndrome (Gorlin syndrome). This pathway is vital for the regulation of cell growth, and differentiation and loss of inhibition of this pathway is associated with development of BCC. The sonic hedgehog protein is the most relevant to BCC; nevertheless, the Patched (PTCH) protein is the ligand-binding component of the hedgehog receptor complex in the cell membrane. The other protein member of the receptor complex, smoothened (SMO), is responsible for transducing hedgehog signaling to downstream genes, leading to abnormal cell proliferation. The importance of this pathway is highlighted by the successful use in advanced forms of BCC of vismodegib, a Food and Drug Administration-approved drug, that selectively inhibits SMO. The UV-specific nucleotide changes in the tumor suppressor genes, TP53 and PTCH, have also been implicated in the development of BCC.

  9. Limbal stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Fernandes Merle

    2004-01-01

    Full Text Available The past two decades have witnessed remarkable progress in limbal stem cell transplantation. In addition to harvesting stem cells from a cadaver or a live related donor, it is now possible to cultivate limbal stem cells in vitro and then transplant them onto the recipient bed. A clear understanding of the basic disease pathology and a correct assessment of the extent of stem cell deficiency are essential. A holistic approach towards management of limbal stem cell deficiency is needed. This also includes management of the underlying systemic disease, ocular adnexal pathology and dry eye. Conjunctival limbal autografts from the healthy contralateral eye are performed for unilateral cases. In bilateral cases, tissue may be harvested from a cadaver or a living related donor; prolonged immunosuppression is needed to avoid allograft rejection in such cases. This review describes the surgical techniques, postoperative treatment regimes (including immunosuppression for allografts, the complications and their management. The short and long-term outcomes of the various modalities reported in the literature are also described.

  10. Alkaline fuel cells applications

    Science.gov (United States)

    Kordesch, Karl; Hacker, Viktor; Gsellmann, Josef; Cifrain, Martin; Faleschini, Gottfried; Enzinger, Peter; Fankhauser, Robert; Ortner, Markus; Muhr, Michael; Aronson, Robert R.

    On the world-wide automobile market technical developments are increasingly determined by the dramatic restriction on emissions as well as the regimentation of fuel consumption by legislation. Therefore there is an increasing chance of a completely new technology breakthrough if it offers new opportunities, meeting the requirements of resource preservation and emission restrictions. Fuel cell technology offers the possibility to excel in today's motive power techniques in terms of environmental compatibility, consumer's profit, costs of maintenance and efficiency. The key question is economy. This will be decided by the costs of fuel cell systems if they are to be used as power generators for future electric vehicles. The alkaline hydrogen-air fuel cell system with circulating KOH electrolyte and low-cost catalysed carbon electrodes could be a promising alternative. Based on the experiences of Kordesch [K. Kordesch, Brennstoffbatterien, Springer, Wien, 1984, ISBN 3-387-81819-7; K. Kordesch, City car with H 2-air fuel cell and lead-battery, SAE Paper No. 719015, 6th IECEC, 1971], who operated a city car hybrid vehicle on public roads for 3 years in the early 1970s, improved air electrodes plus new variations of the bipolar stack assembly developed in Graz are investigated. Primary fuel choice will be a major issue until such time as cost-effective, on-board hydrogen storage is developed. Ammonia is an interesting option. The whole system, ammonia dissociator plus alkaline fuel cell (AFC), is characterised by a simple design and high efficiency.

  11. Cell Culturing of Cytoskeleton

    Science.gov (United States)

    2004-01-01

    Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. Cell culturing, such as this bone cell culture, is an important part of biomedical research. The BioDyn payload includes a tissue engineering investigation. The commercial affiliate, Millenium Biologix, Inc., has been conducting bone implant experiments to better understand how synthetic bone can be used to treat bone-related illnesses and bone damaged in accidents. On STS-95, the BioDyn payload will include a bone cell culture aimed to help develop this commercial synthetic bone product. Millenium Biologix, Inc., is exploring the potential for making human bone implantable materials by seeding its proprietary artificial scaffold material with human bone cells. The product of this tissue engineering experiment using the Bioprocessing Modules (BPMs) on STS-95 is space-grown bone implants, which could have potential for dental implants, long bone grafts, and coating for orthopedic implants such as hip replacements.

  12. RELIABILITY EVALUATION OF PRIMARY CELLS

    African Journals Online (AJOL)

    Dr Obe

    ABSTRACT. Evaluation of the reliability of a primary cell took place in three stages: 192 cells went through a slow-discharged test. A designed experiment was conducted on 144 cells; there were three factors in the experiment: Storage temperature (three levels), thermal shock (two levels) and date code (two levels). 16 cells ...

  13. Sickle Cell Crisis (For Teens)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Sickle Cell Crisis (Pain Crisis) KidsHealth / For Teens / Sickle Cell ... drepanocíticas (Crisis de dolor) What Is a Sickle Cell Crisis? Sickle cell disease changes the shape of ...

  14. Stem Cells in Burn Eschar

    NARCIS (Netherlands)

    van der Veen, V. C.; Vlig, M.; van Milligen-Kummer, F.J.; de Vries, S.I.; Middelkoop, E.; Ulrich, M.

    2012-01-01

    This study compares mesenchymal cells isolated from excised burn wound eschar with adipose-derived stem cells (ASCs) and dermal fibroblasts in their ability to conform to the requirements for multipotent mesenchymal stem cells (MSCs). A population of multipotent stem cells in burn eschar could be an

  15. Sickle Cell Disease (For Teens)

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Sickle Cell Disease KidsHealth / For Teens / Sickle Cell Disease What's in ... Well? Print en español Anemia falciforme What Is Sickle Cell Disease? Sickle cell disease is a blood disorder that's ...

  16. Seventh Edition Fuel Cell Handbook

    Energy Technology Data Exchange (ETDEWEB)

    NETL

    2004-11-01

    Provides an overview of fuel cell technology and research projects. Discusses the basic workings of fuel cells and their system components, main fuel cell types, their characteristics, and their development status, as well as a discussion of potential fuel cell applications.

  17. Advanced Microscopy of Microbial Cells

    DEFF Research Database (Denmark)

    Haagensen, Janus Anders Juul; Regenberg, Birgitte; Sternberg, Claus

    2011-01-01

    Growing awareness of heterogeneity in cells of microbial populations has emphasized the importance of advanced microscopy for visualization and understanding of the molecular mechanisms underlying cell-to-cell variation. In this review, we highlight some of the recent advances in confocal...... for visualization of variation between cells in phenotypic traits such as gene expression....

  18. Primordial germ cell-like cells differentiated in vitro from skin-derived stem cells.

    Directory of Open Access Journals (Sweden)

    Katja Linher

    Full Text Available BACKGROUND: We have previously demonstrated that stem cells isolated from fetal porcine skin have the potential to form oocyte-like cells (OLCs in vitro. However, primordial germ cells (PGCs, which must also be specified during the stem cell differentiation to give rise to these putative oocytes at more advanced stages of culture, were not systematically characterized. The current study tested the hypothesis that a morphologically distinct population of cells derived from skin stem cells prior to OLC formation corresponds to putative PGCs, which differentiate further into more mature gametes. METHODOLOGY/PRINCIPAL FINDINGS: When induced to differentiate in an appropriate microenvironment, a subpopulation of morphologically distinct cells, some of which are alkaline phosphatase (AP-positive, also express Oct4, Fragilis, Stella, Dazl, and Vasa, which are markers indicative of germ cell formation. A known differentially methylated region (DMR within the H19 gene locus, which is demethylated in oocytes after establishment of the maternal imprint, is hypomethylated in PGC-like cells compared to undifferentiated skin-derived stem cells, suggesting that the putative germ cell population undergoes imprint erasure. Additional evidence supporting the germ cell identity of in vitro-generated PGC-like cells is that, when labeled with a Dazl-GFP reporter, these cells further differentiate into GFP-positive OLCs. SIGNIFICANCE: The ability to generate germ cell precursors from somatic stem cells may provide an in vitro model to study some of the unanswered questions surrounding early germ cell formation.

  19. Cell-cell interactions mediate cytoskeleton organization and collective endothelial cell chemotaxis.

    Science.gov (United States)

    Shamloo, Amir

    2014-09-01

    This study investigates the role of cell-cell and cell-ligand interactions in cytoskeleton organization of endothelial cells (ECs) and their directional migration within a microfluidic device. The migration of ECs in response to a biochemical factor was studied. Mathematical analysis of the cell migration pathways and cellular cytoskeleton revealed that directional migration, migration persistence length, migration speed, and cytoskeletal stress fiber alignment can be mediated by the level of cell contacts as well as the presence or absence of a biochemical polarizing factor. It was shown that in the presence of a biochemical polarizing factor, higher cell density and more frequent cell contacts has a reinforcing effect on collective cell chemotaxis. In contrast, in the absence of a polarizing factor, high cell density can decrease or suppress the ability of the cells to migrate. Also, the correlation of actin stress fiber organization and alignment with directional migration of ECs was investigated. It was shown that in the presence of a biochemical polarizing factor, stress fibers within the cytoskeleton of ECs can be significantly aligned parallel to the gradient direction when the cells have higher level of contacts. The results also show that the organization and alignment of actin stress fibers is mediated by cell adhesion junctions during collective cell migration and introduce cell-cell interactions as a key factor during collective cell chemotaxis. © 2014 Wiley Periodicals, Inc.

  20. Proton exchange membrane fuel cells

    CERN Document Server

    Qi, Zhigang

    2013-01-01

    Preface Proton Exchange Membrane Fuel CellsFuel CellsTypes of Fuel CellsAdvantages of Fuel CellsProton Exchange Membrane Fuel CellsMembraneCatalystCatalyst LayerGas Diffusion MediumMicroporous LayerMembrane Electrode AssemblyPlateSingle CellStackSystemCell Voltage Monitoring Module (CVM)Fuel Supply Module (FSM)Air Supply Module (ASM)Exhaust Management Module (EMM)Heat Management Module (HMM)Water Management Module (WMM)Internal Power Supply Module (IPM)Power Conditioning Module (PCM)Communications Module (COM)Controls Module (CM)SummaryThermodynamics and KineticsTheoretical EfficiencyVoltagePo

  1. Materials as stem cell regulators

    Science.gov (United States)

    Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

    2014-01-01

    The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine. PMID:24845994

  2. The role of Rap1 in cell-cell junction formation

    NARCIS (Netherlands)

    Kooistra, M.R.H.

    2008-01-01

    Both epithelial and endothelial cells form cell-cell junctions at the cell-cell contacts to maintain tissue integrity. Proper regulation of cell-cell junctions is required for the organisation of the tissue and to prevent leakage of blood vessels. In endothelial cells, the cell-cell junctions are

  3. Trophoblast lineage cells derived from human induced pluripotent stem cells

    International Nuclear Information System (INIS)

    Chen, Ying; Wang, Kai; Chandramouli, Gadisetti V.R.; Knott, Jason G.; Leach, Richard

    2013-01-01

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro

  4. Trophoblast lineage cells derived from human induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying, E-mail: ying.chen@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Wang, Kai; Chandramouli, Gadisetti V.R. [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Knott, Jason G. [Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University (United States); Leach, Richard, E-mail: Richard.leach@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Department of Obstetrics, Gynecology and Women’s Health, Spectrum Health Medical Group (United States)

    2013-07-12

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro.

  5. Fuel cells in transportation

    Energy Technology Data Exchange (ETDEWEB)

    Erdmann, G. [Technische Univ., Berlin (Germany); Hoehlein, B. [Research Center Juelich (Germany)

    1996-12-01

    A promising new power source for electric drive systems is the fuel cell technology with hydrogen as energy input. The worldwide fuel cell development concentrates on basic research efforts aiming at improving this new technology and at developing applications that might reach market maturity in the very near future. Due to the progress achieved, the interest is now steadily turning to the development of overall systems such as demonstration plants for different purposes: electricity generation, drive systems for road vehicles, ships and railroads. This paper does not present results concerning the market potential of fuel cells in transportation but rather addresses some questions and reflections that are subject to further research of both engineers and economists. Some joint effort of this research will be conducted under the umbrella of the IEA Implementing Agreement 026 - Annex X, but there is a lot more to be done in this challenging but also promising fields. (EG) 18 refs.

  6. Cell Phone Detection Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, Richard M.; Bunch, Kyle J.; Puzycki, David J.; Slaugh, Ryan W.; Good, Morris S.; McMakin, Douglas L.

    2007-10-01

    A team composed of Rick Pratt, Dave Puczyki, Kyle Bunch, Ryan Slaugh, Morris Good, and Doug McMakin teamed together to attempt to exploit cellular telephone features and detect if a person was carrying a cellular telephone into a Limited Area. The cell phone’s electromagnetic properties were measured, analyzed, and tested in over 10 different ways to determine if an exploitable signature exists. The method that appears to have the most potential for success without adding an external tag is to measure the RF spectrum, not in the cell phone band, but between 240 and 400MHz. Figures 1- 7 show the detected signal levels from cell phones from three different manufacturers.

  7. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology (Finland). Dept. of Electrical and Communications Engineering

    1998-12-31

    Photovoltaic research began at the Electron Physics Laboratory of the Helsinki University of Tehnology in 1993, when the laboratory joined the national NEMO 2 research program. During the early stages of the photovoltaic research the main objective was to establish necessary measurement and characterisation routines, as well as to develop the fabrication process. The fabrication process development work has been supported by characterisation and theoretical modelling of the solar cells. Theoretical investigations have been concerned with systematic studies of solar cell parameters, such as diffusion lengths, surface recombination velocities and junction depths. The main result of the modelling and characterisation work is a method which is based on a Laplace transform of the so-called spatial collection efficiency function of the cell. The basic objective of the research has been to develop a fabrication process cheap enough to be suitable for commercial production

  8. Solid Oxide Electrolyser Cell

    DEFF Research Database (Denmark)

    Jensen, Søren Højgaard

    Solid oxide fuel cells (SOFCs) produced at Risø National Laboratory was tested as steam electrolysers under various current densities, operating temperatures and steam partial pressures. At 950 °C and a cell voltage of 1.48V the current density was -3.6A/cm2 with app. 30% H2 + 70% H2O in the inlet...... it is possible to achieve a production price of 0.7 US$/kg H2 with an electricity price of 1.3 US¢/kWh. The cell voltage was measured as function of time. In test ofabout two month of duration a long-term degradation was observed. At 850 °C, -0.5 A/cm2 with 50 vol% H2 the degradation rate was app. 20 mV/1000h...

  9. Human leukaemic cells

    International Nuclear Information System (INIS)

    Andronikashvili, E.L.; Mosulishvili, L.M.; Belokobil'skiy, A.I.; Kharabadze, N.E.; Shonia, N.I.; Desai, L.S.; Foley, G.E.

    1976-01-01

    The results of the determination of trace elements in nucleic acids and histones in human leukaemic cells by activation analysis are reported. The Cr 2+ , Fe 2+ , Zn 2+ , Co 2+ and Sb 2+ content of DNA and RNA of leukaemic cells compared to that of lymphocytes from a patient with infectious mononucleosis or a normal donor are shown tabulated. Similar comparisons are shown for the same trace metal content of histones isolated from the same type of cells. It is felt that the results afford further interesting speculation that trace metals may be involved in the interactions between histones and DNA (especially at the binding sites of histones to DNA), which affect transcription characteristics. (U.K.)

  10. ELECTROMOTIVE FORCE, EMF (CELLS)

    Energy Technology Data Exchange (ETDEWEB)

    Archer, M.D.; Feldberg, S.W.

    1998-09-16

    The voltage or electric potential difference across the terminals of a cell when no current is drawn from it. The emf of a cell is the sum of the electric potential differences (PDs) produced by a separation of charges (electrons or ions) that can occur at each phase boundary (or interface) in the cell. The magnitude of each PD depends on the chemical nature of the two contacting phases. Thus, at the interface between two different metals, some electrons will have moved from the metal with a higher free energy of electrons to the metal with a lower free energy of electrons. The resultant charge separation will produce a PD (just as charge separation produces a voltage across a capacitor) that, at equilibrium, exactly opposes further electron flow. Similarly, PDs can be produced when electrons partition across a metal/solution interface or metal/solid interface, and when ions partition across a solution/membrane/solution interface.

  11. Cell proliferation in carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, S.M.; Ellwein, L.B. (Univ. of Nebraska Medical Center, Omaha (USA))

    1990-08-31

    Chemicals that induce cancer at high doses in animal bioassays often fail to fit the traditional characterization of genotoxins. Many of these nongenotoxic compounds (such as sodium saccharin) have in common the property that they increase cell proliferation in the target organ. A biologically based, computerized description of carcinogenesis was used to show that the increase in cell proliferation can account for the carcinogenicity of nongenotoxic compounds. The carcinogenic dose-response relationship for genotoxic chemicals (such as 2-acetylaminofluorene) was also due in part to increased cell proliferation. Mechanistic information is required for determination of the existence of a threshold for the proliferative (and carcinogenic) response of nongenotoxic chemicals and the estimation of risk for human exposure.

  12. Dense pattern optical multipass cell

    Science.gov (United States)

    Silver, Joel A [Santa Fe, NM

    2009-01-13

    A multiple pass optical cell and method comprising providing a pair of opposed cylindrical mirrors having curved axes with substantially equal focal lengths, positioning an entrance hole for introducing light into the cell and an exit hole for extracting light from the cell, wherein the entrance hole and exit hole are coextensive or non-coextensive, introducing light into the cell through the entrance hole, and extracting light from the cell through the exit hole.

  13. Dense pattern multiple pass cells

    Science.gov (United States)

    Silver, Joel A.; Bomse, David S.

    2010-09-21

    An optical cell and a method of operating an optical cell comprising employing a first mirror comprising a first hole therein at approximately a center of the first mirror and through which laser light enters the cell, employing a second mirror comprising a second hole therein at approximately a center of the second mirror and through which laser light exits the cell, and forming a Lissajous pattern of spots on the mirrors by repeated reflection of laser light entering the cell.

  14. Radiosensitivity of mesothelioma cell lines

    International Nuclear Information System (INIS)

    Haekkinen, A.M.; Laasonen, A.; Linnainmaa, K.; Mattson, K.; Pyrhoenen, S.

    1996-01-01

    The present study was carried out in order to examine the radiosensitivity of malignant pleural mesothelioma cell lines. Cell kinetics, radiation-induced delay of the cell cycle and DNA ploidy of the cell lines were also determined. For comparison an HeLa and a human foetal fibroblast cell line were simultaneously explored. Six previously cytogenetically and histologically characterized mesothelioma tumor cell lines were applied. A rapid tiazolyl blue microtiter (MTT) assay was used to analyze radiosensitivity and cell kinetics and DNA ploidy of the cultured cells were determined by flow cytometry. The survival fraction after a dose of 2 Gy (SF2), parameters α and β of the linear quadratic model (LQ-model) and mean inactivation dose (D MID ) were also estimated. The DNA index of four cell lines equaled 1.0 and two cell lines equaled 1.5 and 1.6. Different mesothelioma cell lines showed a great variation in radiosensitivity. Mean survival fraction after a radiation dose of 2 Gy (SF2) was 0.60 and ranged from 0.36 to 0.81 and mean α value was 0.26 (range 0.48-0.083). The SF2 of the most sensitive diploid mesothelioma cell line was 0.36: Less than that of the foetal fibroblast cell line (0.49). The survival fractions (0.81 and 0.74) of the two most resistant cell lines, which also were aneuploid, were equal to that of the HeLa cell line (0.78). The α/β ratios of the most sensitive cell lines were almost an order of magnitude greater than those of the two most resistant cell lines. Radiation-induced delay of the most resistant aneuploid cell line was similar to that of HeLa cells but in the most sensitive (diploid cells) there was practically no entry into the G1 phase following the 2 Gy radiation dose during 36 h. (orig.)

  15. Interband Cascade Photovoltaic Cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Rui Q. [Univ. of Oklahoma, Norman, OK (United States); Santos, Michael B. [Univ. of Oklahoma, Norman, OK (United States); Johnson, Matthew B. [Univ. of Oklahoma, Norman, OK (United States)

    2014-09-24

    In this project, we are performing basic and applied research to systematically investigate our newly proposed interband cascade (IC) photovoltaic (PV) cells [1]. These cells follow from the great success of infrared IC lasers [2-3] that pioneered the use of quantum-engineered IC structures. This quantum-engineered approach will enable PV cells to efficiently convert infrared radiation from the sun or other heat source, to electricity. Such cells will have important applications for more efficient use of solar energy, waste-heat recovery, and power beaming in combination with mid-infrared lasers. The objectives of our investigations are to: achieve extensive understanding of the fundamental aspects of the proposed PV structures, develop the necessary knowledge for making such IC PV cells, and demonstrate prototype working PV cells. This research will focus on IC PV structures and their segments for utilizing infrared radiation with wavelengths from 2 to 5 μm, a range well suited for emission by heat sources (1,000-2,000 K) that are widely available from combustion systems. The long-term goal of this project is to push PV technology to longer wavelengths, allowing for relatively low-temperature thermal sources. Our investigations address material quality, electrical and optical properties, and their interplay for the different regions of an IC PV structure. The tasks involve: design, modeling and optimization of IC PV structures, molecular beam epitaxial growth of PV structures and relevant segments, material characterization, prototype device fabrication and testing. At the end of this program, we expect to generate new cutting-edge knowledge in the design and understanding of quantum-engineered semiconductor structures, and demonstrate the concepts for IC PV devices with high conversion efficiencies.

  16. Clear cell chondrosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, R.; David, R.; Cierney, G. III

    1985-01-01

    The clinical, radiologic, and histopathologic features of three cases of clear cell chondrosarcoma are described. On radiographs, this rather benign-appearing tumor resembles a chondroblastoma when it occurs at the end of a long bone, and may occasionally show a calcified matrix. However, it has distinctive tumor cells with a centrally placed vesicular nucleus surrounded by clear cytoplasm. The lesion has a low-grade malignancy and is amenable to en bloc surgical resection, which results in a much better prognosis than that of conventional chondrosarcoma.

  17. Iron sulphide solar cells

    Science.gov (United States)

    Ennaoui, A.; Tributsch, H.

    1984-12-01

    The abundant, naturally occurring natural compound pyrite (FeS2) can be used as a semiconducting material for photoelectrochemical and photovoltaic solar cells. Unlike most of the intensively studied photoactive materials, pyrite solar cell production would never be limited by the availability of the elements or by their compatibility with the environment. An energy gap of 0.95 eV has been determined for pyrite, and it is noted that the theoretical efficiency limit for solar energy conversion in this material is of the order of 15-20 percent.

  18. Rectenna solar cells

    CERN Document Server

    Moddel, Garret

    2013-01-01

    Rectenna Solar Cells discusses antenna-coupled diode solar cells, an emerging technology that has the potential to provide ultra-high efficiency, low-cost solar energy conversion. This book will provide an overview of solar rectennas, and provide thorough descriptions of the two main components: the diode, and the optical antenna. The editors discuss the science, design, modeling, and manufacturing of the antennas coupled with the diodes. The book will provide concepts to understanding the challenges, fabrication technologies, and materials required to develop rectenna structures. Written by e

  19. The illuminated plant cell.

    Science.gov (United States)

    Mathur, Jaideep

    2007-11-01

    The past decade has provided biologists with a palette of genetically encoded, multicolored fluorescent proteins. The living plant cell turned into a 'coloring book' and today, nearly every text-book organelle has been highlighted in scintillating fluorescent colors. This review provides a concise listing of the earliest representative fluorescent-protein probes used to highlight various targets within the plant cell, and introduces the idea of using the numerous multicolor, subcellular probes for the development of an early intracellular response profile of plants.

  20. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Electrical and Communications Engineering

    1998-10-01

    Photovoltaic research in the Electron Physics Laboratory started in 1993, when laboratory joined the national TEKES/NEMO 2 research program. Since the beginning of the project, characterization as well as experimentally orientated development of the fabrication process of the solar cells were carried out parallery. The process development research started by the initiatives of the Finnish industry. At the moment a large amount of the laboratory personnel works on solar cell research and the financing comes mainly from external projects. The funding for the research has come from TEKES, Ministry of Education, Finnish Academy, GETA graduate school, special equipment grants of the university, and from the laboratory

  1. Printed biofuel cells

    Science.gov (United States)

    Wang, Joseph; Windmiller, Joshua Ray; Jia, Wenzhao

    2016-11-22

    Methods, systems, and devices are disclosed for implementing a biofuel cell device for extracting energy from a biofuel. In one aspect, a biofuel cell device includes a substrate, an anode including a catalyst to facilitate the conversion of a fuel in a biological fluid in an oxidative process that releases electrons captured at the anode, thereby extracting energy from the fuel substance, a cathode configured on the substrate adjacent to the anode and separated from the anode by a spacing region, and a load electrically coupled to the anode and cathode via electrical interconnects to obtain the extracted energy as electrical energy.

  2. Carbon Nanotube Solar Cells

    OpenAIRE

    Klinger, Colin; Patel, Yogeshwari; Postma, Henk W. Ch.

    2012-01-01

    We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabr...

  3. Fingerprints in cancer cells

    International Nuclear Information System (INIS)

    Servomaa, K.

    1994-01-01

    Gene research has shown that factors causing cancer, or carcinogens, may leave marks typical of each particular carcinogen (fingerprints) in the genotype of the cell. Radiation, for instance, may leave such fingerprints in a cancer cell. In particular, the discovery of a gene called p53 has yielded much new information on fingerprints. It has been discovered, for example, that toxic fungus and UV-radiation each leave fingerprints in the p53 gene. Based on the detection of fingerprints, it may be possible in the future to tell a cancer patient what factor had trigged the maglinancy

  4. Silicon heterojunction solar cells

    CERN Document Server

    Fahrner, W R; Neitzert, H C

    2006-01-01

    The world of today must face up to two contradictory energy problems: on the one hand, there is the sharply growing consumer demand in countries such as China and India. On the other hand, natural resources are dwindling. Moreover, many of those countries which still possess substantial gas and oil supplies are politically unstable. As a result, renewable natural energy sources have received great attention. Among these, solar-cell technology is one of the most promising candidates. However, there still remains the problem of the manufacturing costs of such cells. Many attempts have been made

  5. Gingival squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Amit Walvekar

    2017-01-01

    Full Text Available Oral squamous cell carcinoma (OSCC is the most common epithelial malignancy affecting the oral cavity. The most common sites for the development are lateral surface of tongue and floor of mouth; the least common sites are soft palate, gingiva, and buccal mucosa. Gingival squamous cell carcinoma can mimic a multitude of oral lesions and enlargements, especially those of inflammatory origin. In addition, predisposing and presenting factors are different from those of other OSCCs. Careful examination as well as routine biopsy are crucial for accurate diagnosis.

  6. Microfluidic Cell Culture Device

    Science.gov (United States)

    Takayama, Shuichi (Inventor); Cabrera, Lourdes Marcella (Inventor); Heo, Yun Seok (Inventor); Smith, Gary Daniel (Inventor)

    2014-01-01

    Microfluidic devices for cell culturing and methods for using the same are disclosed. One device includes a substrate and membrane. The substrate includes a reservoir in fluid communication with a passage. A bio-compatible fluid may be added to the reservoir and passage. The reservoir is configured to receive and retain at least a portion of a cell mass. The membrane acts as a barrier to evaporation of the bio-compatible fluid from the passage. A cover fluid may be added to cover the bio-compatible fluid to prevent evaporation of the bio-compatible fluid.

  7. Colorectal Cancer Stem Cells and Cell Death

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, Veronica [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Gaggianesi, Miriam [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Department of Cellular and Molecular Oncology, IRCCS Fondazione Salvatore Maugeri, Via Salvatore Maugeri, 27100 Pavia, PV (Italy); Spina, Valentina; Iovino, Flora [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Dieli, Francesco [Departement of Biopathology and Medicine Biotechnologies, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Stassi, Giorgio, E-mail: giorgio.stassi@unipa.it [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Department of Cellular and Molecular Oncology, IRCCS Fondazione Salvatore Maugeri, Via Salvatore Maugeri, 27100 Pavia, PV (Italy); Todaro, Matilde [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy)

    2011-04-11

    Nowadays it is reported that, similarly to other solid tumors, colorectal cancer is sustained by a rare subset of cancer stem–like cells (CSCs), which survive conventional anticancer treatments, thanks to efficient mechanisms allowing escape from apoptosis, triggering tumor recurrence. To improve patient outcomes, conventional anticancer therapies have to be replaced with specific approaches targeting CSCs. In this review we provide strong support that BMP4 is an innovative therapeutic approach to prevent colon cancer growth increasing differentiation markers expression and apoptosis. Recent data suggest that in colorectal CSCs, protection from apoptosis is achieved by interleukin-4 (IL-4) autocrine production through upregulation of antiapoptotic mediators, including survivin. Consequently, IL-4 neutralization could deregulate survivin expression and localization inducing chemosensitivity of the colon CSCs pool.

  8. Recent Progress in Cell Reprogramming Technology for Cell Transplantation Therapy.

    Science.gov (United States)

    Yamashita, Toru; Abe, Koji

    2016-01-01

    The discovery of induced pluripotent stem (iPS) cells opened the gate for reprogramming technology with which we can change the cell fate through overexpression of master transcriptional factors. Now we can prepare various kinds of neuronal cells directly induced from somatic cells. It has been reported that overexpression of a neuron-specific transcriptional factors might change the cell fate of endogenous astroglia to neuronal cells in vivo. In addition, some research groups demonstrated that chemical compound can induce chemical-induced neuronal cells, without transcriptional factors overexpression. In this review, we briefly review recent progress in the induced neuronal (iN) cells, and discuss the possibility of application for cell transplantation therapy.

  9. Induced pluripotent stem cell lines derived from human somatic cells.

    Science.gov (United States)

    Yu, Junying; Vodyanik, Maxim A; Smuga-Otto, Kim; Antosiewicz-Bourget, Jessica; Frane, Jennifer L; Tian, Shulan; Nie, Jeff; Jonsdottir, Gudrun A; Ruotti, Victor; Stewart, Ron; Slukvin, Igor I; Thomson, James A

    2007-12-21

    Somatic cell nuclear transfer allows trans-acting factors present in the mammalian oocyte to reprogram somatic cell nuclei to an undifferentiated state. We show that four factors (OCT4, SOX2, NANOG, and LIN28) are sufficient to reprogram human somatic cells to pluripotent stem cells that exhibit the essential characteristics of embryonic stem (ES) cells. These induced pluripotent human stem cells have normal karyotypes, express telomerase activity, express cell surface markers and genes that characterize human ES cells, and maintain the developmental potential to differentiate into advanced derivatives of all three primary germ layers. Such induced pluripotent human cell lines should be useful in the production of new disease models and in drug development, as well as for applications in transplantation medicine, once technical limitations (for example, mutation through viral integration) are eliminated.

  10. Bio optofluidics cell sorter: cell-BOCS concept and applications

    Science.gov (United States)

    Roth, Tue; Glückstad, Jesper

    2012-03-01

    The cell-BOCS is a novel microfluidics based cell-sorting instrument utilizing next generation optical trapping technology developed at the Technical University of Denmark. It is targeted emerging bio-medical research and diagnostics markets where it for certain applications offers a number of advantages over conventional fluorescence activated cell-sorting (FACSTM) technology. Advantages include gentle handling of cells, sterile sorting, easy operation, small footprint and lower cost allowing out-of-core-facility use. Application examples are found within sorting of fragile transfected cells, high value samples and primary cell lines, where traditional FACS technology has limited application due to it's droplet-based approach to cell-sorting. In the diagnostics field, in particular applying the cell-BOCS for isolating pure populations of circulating tumor cells is an area that has generated a lot of interest.

  11. Microencapsulating and Banking Living Cells for Cell-Based Medicine

    Directory of Open Access Journals (Sweden)

    Wujie Zhang

    2011-01-01

    Full Text Available A major challenge to the eventual success of the emerging cell-based medicine such as tissue engineering, regenerative medicine, and cell transplantation is the limited availability of the desired cell sources. This challenge can be addressed by cell microencapsulation to overcome the undesired immune response (i.e., to achieve immunoisolation so that non-autologous cells can be used to treat human diseases, and by cell/tissue preservation to bank living cells for wide distribution to end users so that they are readily available when needed in the future. This review summarizes the status quo of research in both cell microencapsulation and banking the microencapsulated cells. It is concluded with a brief outlook of future research directions in this important field.

  12. Stochastic models for cell division

    Science.gov (United States)

    Stukalin, Evgeny; Sun, Sean

    2013-03-01

    The probability of cell division per unit time strongly depends of age of cells, i.e., time elapsed since their birth. The theory of cell populations in the age-time representation is systematically applied for modeling cell division for different spreads in generation times. We use stochastic simulations to address the same issue at the level of individual cells. Our approach unlike deterministic theory enables to analyze the size fluctuations of cell colonies at different growth conditions (in the absence and in the presence of cell death, for initially synchronized and asynchronous cell populations, for conditions of restricted growth). We find the simple quantitative relation between the asymptotic values of relative size fluctuations around mean values for initially synchronized cell populations under growth and the coefficients of variation of generation times. Effect of initial age distribution for asynchronous growth of cell cultures is also studied by simulations. The influence of constant cell death on fluctuations of sizes of cell populations is found to be essential even for small cell death rates, i.e., for realistic growth conditions. The stochastic model is generalized for biologically relevant case that involves both cell reproduction and cell differentiation.

  13. Fuel Cell Testing - Degradation of Fuel Cells and its Impact on Fuel Cell Applications

    OpenAIRE

    PFRANG Andreas

    2008-01-01

    Fuel cells are expected to play a major role in the future energy supply, especially polymer electrolyte membrane fuel cells could become an integral part in future cars. Reduction of degradation of fuel cell performance while keeping fuel cell cost under control is the key for an introduction into mass markets.

  14. Focal Adhesion Kinase regulates cell-cell contact formation in epithelial cells via modulation of Rho

    International Nuclear Information System (INIS)

    Playford, Martin P.; Vadali, Kavita; Cai Xinming; Burridge, Keith; Schaller, Michael D.

    2008-01-01

    Focal Adhesion Kinase (FAK) is a non-receptor tyrosine kinase that plays a key role in cellular processes such as cell adhesion, migration, proliferation and survival. Recent studies have also implicated FAK in the regulation of cell-cell adhesion. Here, evidence is presented showing that siRNA-mediated suppression of FAK levels in NBT-II cells and expression of dominant negative mutants of FAK caused loss of epithelial cell morphology and inhibited the formation of cell-cell adhesions. Rac and Rho have been implicated in the regulation of cell-cell adhesions and can be regulated by FAK signaling. Expression of active Rac or Rho in NBT-II cells disrupted formation of cell-cell contacts, thus promoting a phenotype similar to FAK-depleted cells. The loss of intercellular contacts in FAK-depleted cells is prevented upon expression of a dominant negative Rho mutant, but not a dominant negative Rac mutant. Inhibition of FAK decreased tyrosine phosphorylation of p190RhoGAP and elevated the level of GTP-bound Rho. This suggests that FAK regulates cell-cell contact formation by regulation of Rho

  15. Cell Cycle Related Differentiation of Bone Marrow Cells into Lung Cells

    Energy Technology Data Exchange (ETDEWEB)

    Dooner, Mark; Aliotta, Jason M.; Pimental, Jeffrey; Dooner, Gerri J.; Abedi, Mehrdad; Colvin, Gerald; Liu, Qin; Weier, Heinz-Ulli; Dooner, Mark S.; Quesenberry, Peter J.

    2007-12-31

    Green-fluorescent protein (GFP) labeled marrow cells transplanted into lethally irradiated mice can be detected in the lungs of transplanted mice and have been shown to express lung specific proteins while lacking the expression of hematopoietic markers. We have studied marrow cells induced to transit cell cycle by exposure to IL-3, IL-6, IL-11 and steel factor at different times of culture corresponding to different phases of cell cycle. We have found that marrow cells at the G1/S interface have a 3-fold increase in cells which assume a lung phenotype and that this increase is no longer seen in late S/G2. These cells have been characterized as GFP{sup +} CD45{sup -} and GFP{sup +} cytokeratin{sup +}. Thus marrow cells with the capacity to convert into cells with a lung phenotype after transplantation show a reversible increase with cytokine induced cell cycle transit. Previous studies have shown the phenotype of bone marrow stem cells fluctuates reversibly as these cells traverse cell cycle, leading to a continuum model of stem cell regulation. The present studies indicate that marrow stem cell production of nonhematopoietic cells also fluctuates on a continuum.

  16. Sertoli cells maintain Leydig cell number and peritubular myoid cell activity in the adult mouse testis.

    Directory of Open Access Journals (Sweden)

    Diane Rebourcet

    Full Text Available The Sertoli cells are critical regulators of testis differentiation and development. In the adult, however, their known function is restricted largely to maintenance of spermatogenesis. To determine whether the Sertoli cells regulate other aspects of adult testis biology we have used a novel transgenic mouse model in which Amh-Cre induces expression of the receptor for Diphtheria toxin (iDTR specifically within Sertoli cells. This causes controlled, cell-specific and acute ablation of the Sertoli cell population in the adult animal following Diphtheria toxin injection. Results show that Sertoli cell ablation leads to rapid loss of all germ cell populations. In addition, adult Leydig cell numbers decline by 75% with the remaining cells concentrated around the rete and in the sub-capsular region. In the absence of Sertoli cells, peritubular myoid cell activity is reduced but the cells retain an ability to exclude immune cells from the seminiferous tubules. These data demonstrate that, in addition to support of spermatogenesis, Sertoli cells are required in the adult testis both for retention of the normal adult Leydig cell population and for support of normal peritubular myoid cell function. This has implications for our understanding of male reproductive disorders and wider androgen-related conditions affecting male health.

  17. Cell wall, cytoskeleton, and cell expansion in higher plants.

    Science.gov (United States)

    Bashline, Logan; Lei, Lei; Li, Shundai; Gu, Ying

    2014-04-01

    To accommodate two seemingly contradictory biological roles in plant physiology, providing both the rigid structural support of plant cells and the adjustable elasticity needed for cell expansion, the composition of the plant cell wall has evolved to become an intricate network of cellulosic, hemicellulosic, and pectic polysaccharides and protein. Due to its complexity, many aspects of the cell wall influence plant cell expansion, and many new and insightful observations and technologies are forthcoming. The biosynthesis of cell wall polymers and the roles of the variety of proteins involved in polysaccharide synthesis continue to be characterized. The interactions within the cell wall polymer network and the modification of these interactions provide insight into how the plant cell wall provides its dual function. The complex cell wall architecture is controlled and organized in part by the dynamic intracellular cytoskeleton and by diverse trafficking pathways of the cell wall polymers and cell wall-related machinery. Meanwhile, the cell wall is continually influenced by hormonal and integrity sensing stimuli that are perceived by the cell. These many processes cooperate to construct, maintain, and manipulate the intricate plant cell wall--an essential structure for the sustaining of the plant stature, growth, and life.

  18. Choosing Cell Fate Through a Dynamic Cell Cycle.

    Science.gov (United States)

    Chen, Xinyue; Hartman, Amaleah; Guo, Shangqin

    2015-01-01

    A close relationship between proliferation and cell fate specification has been well documented in many developmental systems. In addition to the gradual cell fate changes accompanying normal development and tissue homeostasis, it is now commonly appreciated that cell fate could also undergo drastic changes, as illustrated by the induction of pluripotency from many differentiated somatic cell types during the process of Yamanaka reprogramming. Strikingly, the drastic cell fate change induced by Yamanaka factors (Oct4, Sox2, Klf4, and c-Myc) is preceded by extensive cell cycle acceleration. Prompted by our recent discovery that progression toward pluripotency from rare somatic cells could bypass the stochastic phase of reprogramming and that a key feature of these somatic cells is an ultrafast cell cycle (~8 h/cycle), we assess whether cell cycle dynamics could provide a general framework for controlling cell fate. Several potential mechanisms on how cell cycle dynamics may impact cell fate determination by regulating chromatin, key transcription factor concentration, or their interactions are discussed. Specific challenges and implications for studying and manipulating cell fate are considered.

  19. BRACHYURY confers cancer stem cell characteristics on colorectal cancer cells.

    Science.gov (United States)

    Sarkar, Debalina; Shields, Brian; Davies, Melanie L; Müller, Jürgen; Wakeman, Jane A

    2012-01-15

    Cancer stem cells (CSCs) are initiating cells in colorectal cancer (CRC). Colorectal tumours undergo epithelial to mesenchymal transition (EMT)-like processes at the invasive front, enabling invasion and metastasis, and recent studies have linked this process to the acquisition of stem cell-like properties. It is of fundamental importance to understand the molecular events leading to the establishment of cancer initiating cells and how these mechanisms relate to cellular transitions during tumourigenesis. We use an in vitro system to recapitulate changes in CRC cells at the invasive front (mesenchymal-like cells) and central mass (epithelial-like cells) of tumours. We show that the mesoderm inducer BRACHYURY is expressed in a subpopulation of CRC cells that resemble invasive front mesenchymal-like cells, where it acts to impose characteristics of CSCs in a fully reversible manner, suggesting reversible formation and modulation of such cells. BRACHYURY, itself regulated by the oncogene β-catenin, influences NANOG and other 'stemness' markers including a panel of markers defining CRC-CSC whose presence has been linked to poor patient prognosis. Similar regulation of NANOG through BRACHYURY was observed in other cells lines, suggesting this might be a pathway common to cancer cells undergoing mesenchymal transition. We suggest that BRACHYURY may regulate NANOG in mesenchymal-like CRC cells to impose a 'plastic-state', allowing competence of cells to respond to signals prompting invasion or metastasis. Copyright © 2011 UICC.

  20. Chromosome aberrations and cell survival in irradiated mammalian cells

    International Nuclear Information System (INIS)

    Tremp, J.

    1981-01-01

    A possible correlation between chromosome aberrations and reduced proliferation capacity or cell death was investigated. Synchronized Chinese hamster fibroblast cells were irradiated with 300 rad of x rays in early G 1 . Despite synchronization the cells reached the subsequent mitosis at different times. The frequency of chromosome aberrations was determined in the postirradiation division at 2-h intervals. The highest frequency occurred in cells with a first cell cycle of medium length. The colony-forming ability of mitotic cells was measured in parallel samples by following the progress of individual mitoses. The proportion of cells forming macrocolonies decreased with increasing cell cycle length, and the number of non-colony-forming cells increased. Irrespective of various first cell cycle lengths and different frequencies of chromosome aberrations, the number of cells forming microcolonies remained constant. A correlation was found between the absence of chromosome aberrations and the ability of cells to form macrocolonies. However, cells with a long first cell cycle formed fewer macrocolonies than expected

  1. Asymmetric cell division in polyploid giant cancer cells and low eukaryotic cells.

    Science.gov (United States)

    Zhang, Dan; Wang, Yijia; Zhang, Shiwu

    2014-01-01

    Asymmetric cell division is critical for generating cell diversity in low eukaryotic organisms. We previously have reported that polyploid giant cancer cells (PGCCs) induced by cobalt chloride demonstrate the ability to use an evolutionarily conserved process for renewal and fast reproduction, which is normally confined to simpler organisms. The budding yeast, Saccharomyces cerevisiae, which reproduces by asymmetric cell division, has long been a model for asymmetric cell division studies. PGCCs produce daughter cells asymmetrically in a manner similar to yeast, in that both use budding for cell polarization and cytokinesis. Here, we review the results of recent studies and discuss the similarities in the budding process between yeast and PGCCs.

  2. Selfish cells in altruistic cell society - a theoretical oncology.

    Science.gov (United States)

    Chigira, M

    1993-09-01

    In multicellular organisms, internal evolution of individual cells is strictly forbidden and 'evolutional' DNA replication should be performed only by the sexual reproduction system. Wholistic negative control system called 'homeostasis' serves all service to germ line cells. All somatic cells are altruistic to the germ line cells. However, in malignant tumors, it seems that individual cells replicate and behave 'selfishly' and evolve against the internal microenvironment. Tumor cells only express the occult selfishness which is programmed in normal cells a priori. This phenomenon is based on the failure of identical DNA replication, and results in 'autonomy' and 'anomie' of cellular society as shown in tumor cells. Genetic programs of normal cells connote this cellular autonomy and anomie introduced by the deletion of regulators on structure genes. It is rather paradoxical that the somatic cells get their freedom from wholistic negative regulation programmed internally. However, this is not a true paradox, since multicellular organisms have clearly been evolved from 'monads' in which cells proliferate without wholistic regulation. Somatic cells revolt against germ cell DNA, called 'selfish replicator' by Dawkins. It is an inevitable destiny that the 'selfishness' coded in genome should be revenged by itself. Selfish replicator in germ cell line should be revolted by its selfishness in the expansion of somatic cells, since they have an orthogenesis to get more selfishness in order to increase their genome. Tumor heterogeneity and progression can be fully explained by this self-contradictory process which produces heterogeneous gene copies different from the original clone in the tumor, although 'selfish' gene replication is the final target of being. Furthermore, we have to discard the concept of clonality of tumor cells since genetic instability is a fundamental feature of tumors. Finally, tumor cells and proto-oncogenes can be considered as the ultimate parasite

  3. Activation of glioma cells generates immune tolerant NKT cells.

    Science.gov (United States)

    Tang, Bo; Wu, Wei; Wei, Xiaowei; Li, Yang; Ren, Gang; Fan, Wenhai

    2014-12-12

    Therapeutic outcomes of glioma are currently not encouraging. Tumor tolerance plays an important role in the pathogenesis of glioma. It is reported that micro RNAs (miR) are associated with tumor development. This study aims to investigate the role of miR-92a in the development of tolerant natural killer T (NKT) cells. In this study, U87 cells (a human glioma cell line) and primary glioma cells were prepared. The assessment of miR-92a was performed by real time RT-PCR. The expression of interleukin (IL)-10 and IL-6 in NKT cells was evaluated by flow cytometry. Results showed that abundant IL-6(+) IL-10(+) NKT cells were detected in glioma tissue. Cultures of glioma cells and NKT cells induced the expression of IL-6 and IL-10 in NKT cells. Glioma cells expressed miR-92a; the latter played a critical role in the induction of IL-6 and IL-10 expression in NKT cells. The expression of the antitumor molecules, including perforin, Fas ligand, and interferon-γ, was significantly attenuated compared with control NKT cells. The IL-6(+) IL-10(+) NKT cells showed less capability in the induction of apoptosis in glioma cells, but showed the immune suppressor functions on CD8(+) T cell activities. We conclude that glioma-derived miR-92a induces IL-6(+) IL-10(+) NKT cells; this fraction of NKT cells can suppress cytotoxic CD8(+) T cells. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Cell biology of mesangial cells: the third cell that maintains the glomerular capillary.

    Science.gov (United States)

    Kurihara, Hidetake; Sakai, Tatsuo

    2017-03-01

    The renal glomerulus consists of glomerular endothelial cells, podocytes, and mesangial cells, which cooperate with each other for glomerular filtration. We have produced monoclonal antibodies against glomerular cells in order to identify different types of glomerular cells. Among these antibodies, the E30 clone specifically recognizes the Thy1.1 molecule expressed on mesangial cells. An injection of this antibody into rats resulted in mesangial cell-specific injury within 15 min, and induced mesangial proliferative glomerulonephritis in a reproducible manner. We examined the role of mesangial cells in glomerular function using several experimental tools, including an E30-induced nephritis model, mesangial cell culture, and the deletion of specific genes. Herein, we describe the characterization of E30-induced nephritis, formation of the glomerular capillary network, mesangial matrix turnover, and intercellular signaling between glomerular cells. New molecules that are involved in a wide variety of mesangial cell functions are also introduced.

  5. Cloning mice and ES cells by nuclear transfer from somatic stem cells and fully differentiated cells.

    Science.gov (United States)

    Wang, Zhongde

    2011-01-01

    Cloning animals by nuclear transfer (NT) has been successful in several mammalian species. In addition to cloning live animals (reproductive cloning), this technique has also been used in several species to establish cloned embryonic stem (ntES) cell lines from somatic cells. It is the latter application of this technique that has been heralded as being the potential means to produce isogenic embryonic stem cells from patients for cell therapy (therapeutic cloning). These two types of cloning differ only in the steps after cloned embryos are produced: for reproductive cloning the cloned embryos are transferred to surrogate mothers to allow them to develop to full term and for therapeutic cloning the cloned embryos are used to derive ntES cells. In this chapter, a detailed NT protocol in mouse by using somatic stem cells (neuron and skin stem cells) and fully differentiated somatic cells (cumulus cells and fibroblast cells) as nuclear donors is described.

  6. Fake news portrayals of stem cells and stem cell research.

    Science.gov (United States)

    Marcon, Alessandro R; Murdoch, Blake; Caulfield, Timothy

    2017-10-01

    This study examines how stem cells and stem cell research are portrayed on websites deemed to be purveyors of distorted and dubious information. Content analysis was conducted on 224 articles from 2015 to 2016, compiled by searching with the keywords 'stem cell(s)' on a list of websites flagged for containing either 'fake' or 'junk science' news. Articles contained various exaggerated positive and negative claims about stem cells and stem cell science, health and science related conspiracy theories, and statements promoting fear and mistrust of conventional medicine. Findings demonstrate the existence of organized misinformation networks, which may lead the public away from accurate information and facilitate a polarization of public discourse.

  7. Development of PEM fuel cell technology at international fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, D.J.

    1996-04-01

    The PEM technology has not developed to the level of phosphoric acid fuel cells. Several factors have held the technology development back such as high membrane cost, sensitivity of PEM fuel cells to low level of carbon monoxide impurities, the requirement to maintain full humidification of the cell, and the need to pressurize the fuel cell in order to achieve the performance targets. International Fuel Cells has identified a hydrogen fueled PEM fuel cell concept that leverages recent research advances to overcome major economic and technical obstacles.

  8. 2-Aminopurine overrides multiple cell cycle checkpoints in BHK cells.

    OpenAIRE

    Andreassen, P R; Margolis, R L

    1992-01-01

    BHK cells blocked at any of several points in the cell cycle override their drug-induced arrest and proceed in the cycle when exposed concurrently to the protein kinase inhibitor 2-aminopurine (2-AP). For cells arrested at various points in interphase, 2-AP-induced cell cycle progression is made evident by arrival of the drug-treated cell population in mitosis. Cells that have escaped from mimosine G1 arrest, from hydroxyurea or aphidicolin S-phase arrest, or from VM-26-induced G2 arrest subs...

  9. NASA Facts, Solar Cells.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    The design and function of solar cells as a source of electrical power for unmanned space vehicles is described in this pamphlet written for high school physical science students. The pamphlet is one of the NASA Facts Science Series (each of which consists of four pages) and is designed to fit in the standard size three-ring notebook. Review…

  10. Dental pulp stem cells

    DEFF Research Database (Denmark)

    Ashri, N. Y.; Ajlan, S. A.; Aldahmash, Abdullah M.

    2015-01-01

    Inflammatory periodontal disease is a major cause of loss of tooth-supporting structures. Novel approaches for regeneration of periodontal apparatus is an area of intensive research. Periodontal tissue engineering implies the use of appropriate regenerative cells, delivered through a suitable sca...

  11. Granular Cell Tumor

    African Journals Online (AJOL)

    Necrosis within the tumor was absent, no mitosis was. Granular cell tumors are seldom diagnosed identified in the section and the edges of the accurately clinically. The lesion in this case was sample were tumor free (Figure 2). mistaken for a sebaceous cyst and following ulceration resembled carcinoma of the vulvar.

  12. Cell Membrane Coating Nanotechnology.

    Science.gov (United States)

    Fang, Ronnie H; Kroll, Ashley V; Gao, Weiwei; Zhang, Liangfang

    2018-03-27

    Nanoparticle-based therapeutic, prevention, and detection modalities have the potential to greatly impact how diseases are diagnosed and managed in the clinic. With the wide range of nanomaterials available, the rational design of nanocarriers on an application-specific basis has become increasingly commonplace. Here, a comprehensive overview is provided on an emerging platform: cell-membrane-coating nanotechnology. As a fundamental unit of biology, cells carry out a wide range of functions, including the remarkable ability to interface and interact with their surrounding environment. Instead of attempting to replicate such functions via synthetic techniques, researchers are now directly leveraging naturally derived cell membranes as a means of bestowing nanoparticles with enhanced biointerfacing capabilities. This top-down technique is facile, highly generalizable, and has the potential to greatly augment existing nanocarriers. Further, the introduction of a natural membrane substrate onto nanoparticles surfaces has enabled additional applications beyond those traditionally associated with nanomedicine. Despite its relative youth, there exists an impressive body of literature on cell membrane coating, which is covered here in detail. Overall, there is still significant room for development, as researchers continue to refine existing workflows while finding new and exciting applications that can take advantage of this developing technology. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Criticality in cell differentiation

    Indian Academy of Sciences (India)

    Indrani Bose

    2017-11-09

    Nov 9, 2017 ... diverse as ecosystems, financial markets, population biology and complex diseases (Scheffer et al. 2009, 2012). Similar studies on the signatures of regime .... and in the maintenance of homeostasis in adult tissues. (Semrau and van Oudenaarden 2015). Cell differentiation occurs when the undifferentiated ...

  14. The cell phone dilemma

    International Nuclear Information System (INIS)

    Mertens, J.; Wiedemann, P.

    2008-01-01

    It is explored if and how the Media generate social technophobias and in particular provoke antagonism against Cell Phones. The role of science and politics in this context is discussed. The authors caution against a progressive creation of hysteria in risk debates. (orig.)

  15. Infections and endothelial cells

    NARCIS (Netherlands)

    Keller, Tymen T.; Mairuhu, Albert T. A.; de Kruif, Martijn D.; Klein, Saskia K.; Gerdes, Victor E. A.; ten Cate, Hugo; Brandjes, Dees P. M.; Levi, Marcel; van Gorp, Eric C. M.

    2003-01-01

    Systemic infection by various pathogens interacts with the endothelium and may result in altered coagulation, vasculitis and atherosclerosis. Endothelium plays a role in the initiation and regulation of both coagulation and fibrinolysis. Exposure of endothelial cells may lead to rapid activation of

  16. Goblet cell carcinoids

    DEFF Research Database (Denmark)

    Olsen, Ingrid Holst; Holt, Nanna; Langer, Seppo W

    2015-01-01

    BACKGROUND: Appendiceal goblet cell carcinoids (GCCs) exhibit neuroendocrine and adenocarcinoma features. PATIENTS AND METHODS: Analysis of demography, pathology, prognostic markers, treatment and survival in 83 GCC patients (f/m: 56/27) diagnosed 1992-2013. RESULTS: Median age for f/m was 59...

  17. Cell Phone RF Radiation

    Science.gov (United States)

    Abdul-Razzaq, Wathiq

    2015-01-01

    In a recent article in "Physics Today," Meredith and Redish emphasized the need to make introductory physics courses beneficial for life sciences majors. In this study, a lab activity is proposed to measure the intensity of electromagnetic waves emitted by cell phones and connect these measurements to various standards, biological…

  18. Solid Oxide Fuel Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The solid oxide fuel cell comprising a metallic support material, an active anode layer consisting of a good hydrocarbon cracking catalyst, an electrolyte layer, an active cathode layer, and a transition layer consisting of preferably a mixture of LSM and a ferrite to the cathode current collector...

  19. Reliance Cell Operator

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Reliance Cell Operator. Reliance was the only bidder for cellular licences for Assam and NE. Services allowed only in Guwahati and Shillong due to “security reasons”. Only major cities in the country with only one operator.

  20. FUEL CELL BIBLIOGRAPHY

    Science.gov (United States)

    References in this bibliography on fuel cells are arranged alphabetically by the authors. References for which no author is cited are arranged alphabetically by title under the general heading, Anon. The numerous references cover the time period of 1895 to 1961.

  1. Criticality in cell differentiation

    Indian Academy of Sciences (India)

    The differentiation dynamics have both deterministic andstochastic components. Several theoretical studies suggest that cell differentiation is a bifurcation phenomenon, well-knownin dynamical systems theory. The bifurcation point has the character of a critical point with the system dynamics exhibitingspecific features in its ...

  2. Mammalian cell biology

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Progress is reported on studies of the molecular biology and functional changes in cultured mammalian cells following exposure to x radiation, uv radiation, fission neutrons, or various chemical environmental pollutants alone or in combinations. Emphasis was placed on the separate and combined effects of polycyclic aromatic hydrocarbons released during combustion of fossil fuels and ionizing and nonionizing radiations. Sun lamps, which emit a continuous spectrum of near ultraviolet light of 290 nm to 315 nm were used for studies of predictive cell killing due to sunlight. Results showed that exposure to uv light (254 nm) may not be adequate to predict effects produced by sunlight. Data are included from studies on single-strand breaks and repair in DNA of cultured hamster cells exposed to uv or nearultraviolet light. The possible interactions of the polycyclic aromatic hydrocarbon 7,12-dimethylbenz(a)-anthracene (DmBA) alone or combined with exposure to x radiation, uv radiation (254 nm) or near ultraviolet simulating sunlight were compared for effects on cell survival

  3. Cell Towers and Songbirds

    Science.gov (United States)

    Klosterman, Michelle; Mesa, Jennifer; Milton, Katie

    2009-01-01

    This article describes how our common addiction to cell phones was used to launch a discussion about their use, impacts on the environment, and connections to issues of civic concern. By encouraging middle school science students to adopt the perspectives of special-interest groups debating communication tower restrictions designed to protect…

  4. Fuel cell electronics packaging

    National Research Council Canada - National Science Library

    Kuang, Ken; Easler, Keith

    2007-01-01

    ... more energy independent. Despite the fact that the primary focus of the new initiative revolved around automotive technologies, the President's Hydrogen Fuel Initiative was crafted into a balanced program that benefited a wide range of technologies and applications, including micro, portable, stationary fuel cells. This massive effort was given an addition...

  5. Cell control with agents

    NARCIS (Netherlands)

    Ir Peter Boots; Ir. Dick van Schenk Brill

    2000-01-01

    A software system is described that uses the agent concept in the Cell Control layer. Important design goals are: the system continues as good as possible after a process crash, crashed processes are recreated whenever possible, and equivalent workstations are allocated dynamically. This project is

  6. Human leukaemic cells

    International Nuclear Information System (INIS)

    Andronikashvili, E.L.; Mosulishvili, L.M.; Belokobil'skiy, A.I.; Kharabadze, N.E.; Shonia, N.I.; Desai, L.S.; Foley, G.E.

    1976-01-01

    Trace metals were measured by neutron-activation analyses in purified nucleic acids and histone(s) of lymphocytes from patients with acute lymphocytic leukaemia or infectious mononucleosis, and from normal donors. DNA isolated from lymphocytes of a patient with infectious mononucleosis and a normal donor showed a high content of Cr 2+ , Sb 2+ , Fe 2+ , Zn 2+ , whereas DNA of lymphoblasts from a patient with acute lymphocytic leukaemia had a lower content of these trace metals, but the Co 2+ content was 20-fold higher than in DNA of normal donor lymphocytic cells. Total histones from leukaemic cells had higher contents of most of the trace metals except for Zn 2+ , which was present in lesser concentration than in histones from normal donor lymphocytic cells. Lysine-rich (F1) histones showed lower contents of Cr 2+ , Sb 2+ and Co 2+ , whereas arginine-rich (F3) histones had significantly higher contents of these trace metals. These observations may be of interest in that F3 histones more effectively inhibit RNA synthesis in human lymphocytic cells than do other species of histones. (author)

  7. Sickle cell anemia

    African Journals Online (AJOL)

    salah

    to chronic pain, strokes and premature death has been reported by CBS News,. U.S.A. in background of the fact that ..... Since the pain of sickle cell ane- mia comes from blood vessels be- ing blocked off, another method ... from the umbilical cord and placenta at child birth. Cord blood transplants are especially promising for ...

  8. Eukaryotic Cell Panorama

    Science.gov (United States)

    Goodsell, David S.

    2011-01-01

    Diverse biological data may be used to create illustrations of molecules in their cellular context. This report describes the scientific results that support an illustration of a eukaryotic cell, enlarged by one million times to show the distribution and arrangement of macromolecules. The panoramic cross section includes eight panels that extend…

  9. Unmasking circulating tumor cells

    NARCIS (Netherlands)

    Swennenhuis, Joost Franciscus

    2017-01-01

    The number of Circulating Tumor Cells (CTCs) that can be isolated from blood of cancer patients is prognostic for the course of the disease. A higher number of CTCs correlates with a worse prognosis. A change from a higher number to a lower number of CTCs indicates a benefit of the current treatment

  10. Intraosseous acinic cell carcinoma

    African Journals Online (AJOL)

    2011-12-17

    Dec 17, 2011 ... provisional diagnosis of benign odontogenic tumor was given. Intraosseous acinic cell carcinoma. V Hiremath, N Mishra1, SG Patil2. Departments of Oral Pathology and 1Oral Medicine and Radiology, Mansarovar Dental College, Bhopal, 2 Department Of. Oral and Maxillofacial Surgery, H.K.E' S.N. Dental ...

  11. Nature's Solar Cell

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 2. Nature's Solar Cell. Stephen Suresh Gautham Nadig. Research News Volume 1 Issue 2 February 1996 pp 102-104. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/02/0102-0104 ...

  12. Sickle Cell Anemia Bibliography.

    Science.gov (United States)

    Christy, Steven C.

    Presents sources for the acquisition of medical, social, psychological, educational, and practical knowledge of sickle cell anemia. The materials listed are designed to help parents, educators, and public service workers. Materials include journal articles, films, brochures, slides, and fact sheets. The usual bibliographic information is given.…

  13. Porcine embryonic stem cells

    DEFF Research Database (Denmark)

    Hall, Vanessa Jane

    2008-01-01

    The development of porcine embryonic stem cell lines (pESC) has received renewed interest given the advances being made in the production of immunocompatible transgenic pigs. However, difficulties are evident in the production of pESCs in-vitro. This may largely be attributable to differences...

  14. Stem cell therapy for diabetes

    Directory of Open Access Journals (Sweden)

    K O Lee

    2012-01-01

    Full Text Available Stem cell therapy holds immense promise for the treatment of patients with diabetes mellitus. Research on the ability of human embryonic stem cells to differentiate into islet cells has defined the developmental stages and transcription factors involved in this process. However, the clinical applications of human embryonic stem cells are limited by ethical concerns, as well as the potential for teratoma formation. As a consequence, alternative forms of stem cell therapies, such as induced pluripotent stem cells, umbilical cord stem cells and bone marrow-derived mesenchymal stem cells, have become an area of intense study. Recent advances in stem cell therapy may turn this into a realistic treatment for diabetes in the near future.

  15. Beta cell adaptation in pregnancy

    DEFF Research Database (Denmark)

    Nielsen, Jens Høiriis

    2016-01-01

    Pregnancy is associated with a compensatory increase in beta cell mass. It is well established that somatolactogenic hormones contribute to the expansion both indirectly by their insulin antagonistic effects and directly by their mitogenic effects on the beta cells via receptors for prolactin...... and growth hormone expressed in rodent beta cells. However, the beta cell expansion in human pregnancy seems to occur by neogenesis of beta cells from putative progenitor cells rather than by proliferation of existing beta cells. Claes Hellerström has pioneered the research on beta cell growth for decades......, but the mechanisms involved are still not clarified. In this review the information obtained in previous studies is recapitulated together with some of the current attempts to resolve the controversy in the field: identification of the putative progenitor cells, identification of the factors involved...

  16. Dendritic cell neoplasms: an overview.

    Science.gov (United States)

    Kairouz, Sebastien; Hashash, Jana; Kabbara, Wadih; McHayleh, Wassim; Tabbara, Imad A

    2007-10-01

    Dendritic cell neoplasms are rare tumors that are being recognized with increasing frequency. They were previously classified as lymphomas, sarcomas, or histiocytic neoplasms. The World Health Organization (WHO) classifies dendritic cell neoplasms into five groups: Langerhans' cell histiocytosis, Langerhans' cell sarcoma, Interdigitating dendritic cell sarcoma/tumor, Follicular dendritic cell sarcoma/tumor, and Dendritic cell sarcoma, not specified otherwise (Jaffe, World Health Organization classification of tumors 2001; 273-289). Recently, Pileri et al. provided a comprehensive immunohistochemical classification of histiocytic and dendritic cell tumors (Pileri et al., Histopathology 2002;59:161-167). In this article, a concise overview regarding the pathological, clinical, and therapeutic aspects of follicular dendritic, interdigitating dendritic, and Langerhans' cell tumors is presented.

  17. Clear cells in acral melanoma.

    Science.gov (United States)

    Schmuth, M; Spötl, L; Zelger, B; Weinlich, G; Zelger, B

    2001-01-01

    Acral melanoma may present clinically and histologically with atypical features causing a delay in proper diagnosis. The aim of the present study was to assess the frequency of a histological variant with clear cell changes. Clinical information, hematoxylin & eosin stained paraffin sections and immunohistochemical staining profiles were reviewed in 49 cases of acral melanoma. Twenty-one (43%) specimens contained tumor cells with clear cell changes in focal areas, whereas in 7 (14%) specimens clear cells were the major tumor constituting cells. The tumor thickness ranged from melanoma in situ to 14 mm. Immunohistochemistry demonstrated weak staining for S100 and HMB45 as well as strong positivity for Melan A and NK1C3. Recognition of clear cell features is important since differential diagnosis includes a variety of other clear cell malignancies, among them metastasis from renal cell carcinoma, clear cell sarcoma and hidradenocarcinoma.

  18. BIOLOGICALLY INSPIRED HARDWARE CELL ARCHITECTURE

    DEFF Research Database (Denmark)

    2010-01-01

    Disclosed is a system comprising: - a reconfigurable hardware platform; - a plurality of hardware units defined as cells adapted to be programmed to provide self-organization and self-maintenance of the system by means of implementing a program expressed in a programming language defined as DNA...... language, where each cell is adapted to communicate with one or more other cells in the system, and where the system further comprises a converter program adapted to convert keywords from the DNA language to a binary DNA code; where the self-organisation comprises that the DNA code is transmitted to one...... or more of the cells, and each of the one or more cells is adapted to determine its function in the system; where if a fault occurs in a first cell and the first cell ceases to perform its function, self-maintenance is performed by that the system transmits information to the cells that the first cell has...

  19. Pericytes limit tumor cell metastasis

    DEFF Research Database (Denmark)

    Xian, Xiaojie; Håkansson, Joakim; Ståhlberg, Anders

    2006-01-01

    Previously we observed that neural cell adhesion molecule (NCAM) deficiency in beta tumor cells facilitates metastasis into distant organs and local lymph nodes. Here, we show that NCAM-deficient beta cell tumors grew leaky blood vessels with perturbed pericyte-endothelial cell-cell interactions...... and deficient perivascular deposition of ECM components. Conversely, tumor cell expression of NCAM in a fibrosarcoma model (T241) improved pericyte recruitment and increased perivascular deposition of ECM molecules. Together, these findings suggest that NCAM may limit tumor cell metastasis by stabilizing...... the microvessel wall. To directly address whether pericyte dysfunction increases the metastatic potential of solid tumors, we studied beta cell tumorigenesis in primary pericyte-deficient Pdgfb(ret/ret) mice. This resulted in beta tumor cell metastases in distant organs and local lymph nodes, demonstrating a role...

  20. Stem Cells and Tissue Engineering

    CERN Document Server

    Pavlovic, Mirjana

    2013-01-01

    Stem cells are the building blocks for all other cells in an organism. The human body has about 200 different types of cells and any of those cells can be produced by a stem cell. This fact emphasizes the significance of stem cells in transplantational medicine, regenerative therapy and bioengineering. Whether embryonic or adult, these cells can be used for the successful treatment of a wide range of diseases that were not treatable before, such as osteogenesis imperfecta in children, different forms of leukemias, acute myocardial infarction, some neural damages and diseases, etc. Bioengineering, e.g. successful manipulation of these cells with multipotential capacity of differentiation toward appropriate patterns and precise quantity, are the prerequisites for successful outcome and treatment. By combining in vivo and in vitro techniques, it is now possible to manage the wide spectrum of tissue damages and organ diseases. Although the stem-cell therapy is not a response to all the questions, it provides more...