40 results on '"Stapfer, G"'
Search Results
2. Detector description and performance for the first coincidence observations between LIGO and GEO
- Author
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Abbott, B., Abbott, R., Adhikari, R., Ageev, A., Allen, B., Amin, R., Anderson, S.B., Anderson, W.G., Araya, M., Armandula, H., Asiri, F., Aufmuth, P., Aulbert, C., Babak, S., Balasubramanian, R., Ballmer, S., Barish, B.C., Barker, D., Barker-Patton, C., Barnes, M., Barr, B., Barton, M.A., Bayer, K., Beausoleil, R., Belczynski, K., Bennett, R., Berukoff, S.J., Betzwieser, J., Bhawal, B., Bilenko, I.A., Billingsley, G., Black, E., Blackburn, K., Bland-Weaver, B., Bochner, B., Bogue, L., Bork, R., Bose, S., Brady, P.R., Braginsky, V.B., Brau, J.E., Brown, D.A., Brozek, S., Bullington, A., Buonanno, A., Burgess, R., Busby, D., Butler, W.E., Byer, R.L., Cadonati, L., Cagnoli, G., Camp, J.B., Cantley, C.A., Cardenas, L., Carter, K., Casey, M.M., Castiglione, J., Chandler, A., Chapsky, J., Charlton, P., Chatterji, S., Chen, Y., Chickarmane, V., Chin, D., Christensen, N., Churches, D., Colacino, C., Coldwell, R., Coles, M., Cook, D., Corbitt, T., Coyne, D., Creighton, J.D.E., Creighton, T.D., Crooks, D.R.M., Csatorday, P., Cusack, B.J., Cutler, C., D'Ambrosio, E., Danzmann, K., Davies, R., Daw, E., DeBra, D., Delker, T., DeSalvo, R., Dhurandar, S., Dı́az, M., Ding, H., Drever, R.W.P., Dupuis, R.J., Ebeling, C., Edlund, J., Ehrens, P., Elliffe, E.J., Etzel, T., Evans, M., Evans, T., Fallnich, C., Farnham, D., Fejer, M.M., Fine, M., Finn, L.S., Flanagan, É., Freise, A., Frey, R., Fritschel, P., Frolov, V., Fyffe, M., Ganezer, K.S., Giaime, J.A., Gillespie, A., Goda, K., González, G., Goßler, S., Grandclément, P., Grant, A., Gray, C., Gretarsson, A.M., Grimmett, D., Grote, H., Grunewald, S., Guenther, M., Gustafson, E., Gustafson, R., Hamilton, W.O., Hammond, M., Hanson, J., Hardham, C., Harry, G., Hartunian, A., Heefner, J., Hefetz, Y., Heinzel, G., Heng, I.S., Hennessy, M., Hepler, N., Heptonstall, A., Heurs, M., Hewitson, M., Hindman, N., Hoang, P., Hough, J., Hrynevych, M., Hua, W., Ingley, R., Ito, M., Itoh, Y., Ivanov, A., Jennrich, O., Johnson, W.W., Johnston, W., Jones, L., Jungwirth, D., Kalogera, V., Katsavounidis, E., Kawabe, K., Kawamura, S., Kells, W., Kern, J., Khan, A., Killbourn, S., Killow, C.J., Kim, C., King, C., King, P., Klimenko, S., Kloevekorn, P., Koranda, S., Kötter, K., Kovalik, J., Kozak, D., Krishnan, B., Landry, M., Langdale, J., Lantz, B., Lawrence, R., Lazzarini, A., Lei, M., Leonhardt, V., Leonor, I., Libbrecht, K., Lindquist, P., Liu, S., Logan, J., Lormand, M., Lubinski, M., Lück, H., Lyons, T.T., Machenschalk, B., MacInnis, M., Mageswaran, M., Mailand, K., Majid, W., Malec, M., Mann, F., Marin, A., Márka, S., Maros, E., Mason, J., Mason, K., Matherny, O., Matone, L., Mavalvala, N., McCarthy, R., McClelland, D.E., McHugh, M., McNamara, P., Mendell, G., Meshkov, S., Messenger, C., Mitrofanov, V.P., Mitselmakher, G., Mittleman, R., Miyakawa, O., Miyoki, S., Mohanty, S., Moreno, G., Mossavi, K., Mours, B., Mueller, G., Mukherjee, S., Myers, J., Nagano, S., Nash, T., Naundorf, H., Nayak, R., Newton, G., Nocera, F., Nutzman, P., Olson, T., O'Reilly, B., J. Ottaway, D., Ottewill, A., Ouimette, D., Overmier, H., Owen, B.J., Papa, M.A., Parameswariah, C., Parameswariah, V., Pedraza, M., Penn, S., Pitkin, M., Plissi, M., Pratt, M., Quetschke, V., Raab, F., Radkins, H., Rahkola, R., Rakhmanov, M., Rao, S.R., Redding, D., Regehr, M.W., Regimbau, T., Reilly, K.T., Reithmaier, K., Reitze, D.H., Richman, S., Riesen, R., Riles, K., Rizzi, A., Robertson, D.I., Robertson, N.A., Robison, L., Roddy, S., Rollins, J., Romano, J.D., Romie, J., Rong, H., Rose, D., Rotthoff, E., Rowan, S., Rüdiger, A., Russell, P., Ryan, K., Salzman, I., Sanders, G.H., Sannibale, V., Sathyaprakash, B., Saulson, P.R., Savage, R., Sazonov, A., Schilling, R., Schlaufman, K., Schmidt, V., Schofield, R., Schrempel, M., Schutz, B.F., Schwinberg, P., Scott, S.M., Searle, A.C., Sears, B., Seel, S., Sengupta, A.S., Shapiro, C.A., Shawhan, P., Shoemaker, D.H., Shu, Q.Z., Sibley, A., Siemens, X., Sievers, L., Sigg, D., Sintes, A.M., Skeldon, K., Smith, J.R., Smith, M., Smith, M.R., Sneddon, P., Spero, R., Stapfer, G., Strain, K.A., Strom, D., Stuver, A., Summerscales, T., Sumner, M.C., Sutton, P.J., Sylvestre, J., Takamori, A., Tanner, D.B., Tariq, H., Taylor, I., Taylor, R., Thorne, K.S., Tibbits, M., Tilav, S., Tinto, M., Tokmakov, K.V., Torres, C., Torrie, C., Traeger, S., Traylor, G., Tyler, W., Ugolini, D., Vallisneri, M., van Putten, M., Vass, S., Vecchio, A., Vorvick, C., Vyatchanin, S.P., Wallace, L., Walther, H., Ward, H., Ware, B., Watts, K., Webber, D., Weidner, A., Weiland, U., Weinstein, A., Weiss, R., Welling, H., Wen, L., Wen, S., Whelan, J.T., Whitcomb, S.E., Whiting, B.F., Willems, P.A., Williams, P.R., Williams, R., Willke, B., Wilson, A., Winjum, B.J., Winkler, W., Wise, S., Wiseman, A.G., Woan, G., Wooley, R., Worden, J., Yakushin, I., Yamamoto, H., Yoshida, S., Zawischa, I., Zhang, L., Zotov, N., Zucker, M., and Zweizig, J.
- Published
- 2004
- Full Text
- View/download PDF
3. Lunar base thermoelectric power station study
- Author
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Determan, William, Frye, Patrick, Mondt, Jack, Fleurial, Jean-Pierre, Johnson, Ken, Stapfer, G, Brooks, Michael D, and Heshmatpour, Ben
- Published
- 2006
4. influence of the SARS-CoV-2 lockdown on patients with inflammatory rheumatic diseases on their adherence to immunomodulatory medication: a cross sectional study over 3 months in Germany.
- Author
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Hasseli, R, Müller-Ladner, U, Keil, F, Broll, M, Dormann, A, Fräbel, C, Hermann, W, Heinmüller, C -J, Hoyer, B F, Löffler, F, Özden, F, Pfeiffer, U, Saech, J, Schneidereit, T, Schlesinger, A, Schwarting, A, Specker, C, Stapfer, G, Steinmüller, M, and Storck-Müller, K
- Subjects
DRUG therapy for rheumatism ,PATIENT compliance ,CROSS-sectional method ,ACADEMIC medical centers ,QUESTIONNAIRES ,PRIMARY health care ,TERMINATION of treatment ,DESCRIPTIVE statistics ,STAY-at-home orders ,DEPARTMENTS ,HEALTH behavior ,HEALTH facilities ,COVID-19 pandemic ,IMMUNOMODULATORS ,MEDICAL practice ,RHEUMATISM - Abstract
Objectives To evaluate the influence of the SARS-CoV-2 pandemic on the adherence of patients with inflammatory rheumatic diseases (IRD) to their immunomodulatory medication during the three-month lockdown in Germany. Methods From 16
th March until 15th June 2020, IRD patients from private practices and rheumatology departments were asked to answer a questionnaire addressing their behaviour with respect to their immunomodulating therapy. Eight private practices and nine rheumatology departments that included rheumatology primary care centres and university hospitals participated. A total of 4252 questionnaires were collected and evaluated. Results The majority of patients (54%) were diagnosed with RA, followed by psoriatic arthritis (14%), ankylosing spondylitis (10%), connective tissue diseases (12%) and vasculitides (6%). Most of the patients (84%) reported to continue their immunomodulatory therapy. Termination of therapy was reported by only 3% of the patients. The results were independent from the type of IRD, the respective immunomodulatory therapy and by whom the patients were treated (private practices vs rheumatology departments). Younger patients (<60 years) reported just as often as older patients to discontinue their therapy. Conclusion The data show that most of the patients continued their therapy in spite of the pandemic. A significant change in behaviour with regard to their immunomodulatory therapy was not observed during the three months of observation. The results support the idea that the immediate release of recommendations of the German Society of Rheumatology were well received, supporting the well-established physician–patient relationship in times of a crisis. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
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5. Search for gravitational waves from primordial black hole binary coalescences in the galactic halo
- Author
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Abbott, B., Abbott, R., Adhikari, R., Ageev, A., Allen, B., Amin, R., Anderson, S., Anderson, W., Araya, M., Armandula, H., Ashley, M., Asiri, F., Aufmuth, P., Aulbert, C., Babak, S., Balasubramanian, R., Ballmer, S., Barish, B., Barker, C., Barker, D., Barnes, M., Barr, B., Barton, M., Bayer, K., Beausoleil, R., Belczynski, K., Bennett, R., Berukoff, S., Betzwieser, J., Bhawal, B., Bilenko, I., Billingsley, G., Black, E., Blackburn, K., Blackburn, L., Bland, B., Bochner, B., Bogue, L., Bork, R., Bose, S., Brady, P., Braginsky, V., Brau, J., Brown, D., Bullington, A., Bunkowski, A., Buonanno, A., Burgess, R., Busby, D., Butler, W., Byer, R., Cadonati, L., Cagnoli, G., Camp, J., Cantley, C., Cardenas, L., Carter, K., Casey, M., Castiglione, J., Chandler, A., Chapsky, J., Charlton, P., Chatterji, S., Chelkowski, S., Chen, Y., Chickarmane, V., Chin, D., Christensen, N., Churches, D., Cokelaer, T., Colacino, C., Coldwell, R., Coles, M., Cook, D., Corbitt, T., Coyne, D., Creighton, J., Creighton, T., Crooks, D., Csatorday, P., Cusack, B., Cutler, C., D'Ambrosio, E., Danzmann, K., Daw, E., DeBra, D., Delker, T., Dergachev, V., DeSalvo, R., Dhurandhar, S., Di Credico, A., Diaz, M., Ding, H., Drever, R., Dupuis, R., Edlund, J., Ehrens, P., Elliffe, E., Etzel, T., Evans, M., Evans, T., Fairhurst, S., Fallnich, C., Farnham, D., Fejer, M., Findley, T., Fine, M., Finn, L., Franzen, K., Freise, A., Frey, R., Fritschel, P., Frolov, V., Fyffe, M., Ganezer, K., Garofoli, J., Giaime, J., Gillespie, A., Goda, K., Gonzalez, G., Gossler, S., Grandclement, P., Grant, A., Gray, C., Gretarsson, A., Grimmett, D., Grote, H., Grunewald, S., Guenther, M., Gustafson, E., Gustafson, R., Hamilton, W., Hammond, M., Hanson, J., Hardham, C., Harms, J., Harry, G., Hartunian, A., Heefner, J., Hefetz, Y., Heinzel, G., Heng, I., Hennessy, M., Hepler, N., Heptonstall, A., Heurs, M., Hewitson, M., Hild, S., Hindman, N., Hoang, P., Hough, J., Hrynevych, M., Hua, W., Ito, M., Itoh, Y., Ivanov, A., Jennrich, O., Johnson, B., Johnson, W., Johnston, W., Jones, D., Jones, L., Jungwirth, D., Kalogera, V., Katsavounidis, E., Kawabe, K., Kawamura, S., Kells, W., Kern, J., Khan, A., Killbourn, S., Killow, C., Kim, C., King, C., King, P., Klimenko, S., Koranda, S., Kotter, K., Kovalik, J., Kozak, D., Krishnan, B., Landry, M., Langdale, J., Lantz, B., Lawrence, R., Lazzarini, A., Lei, M., Leonor, I., Libbrecht, K., Libson, A., Lindquist, P., Liu, S., Logan, J., Lormand, M., Lubinski, M., Lück, H., Lyons, T., Machenschalk, B., MacInnis, M., Mageswaran, M., Mailand, K., Majid, W., Malec, M., Mann, F., Marin, A., Marka, S., Maros, E., Mason, J., Mason, K., Matherny, O., Matone, L., Mavalvala, N., McCarthy, R., McClelland, D., McHugh, M., McNabb, J., Mendell, G., Mercer, R., Meshkov, S., Messaritaki, E., Messenger, C., Mitrofanov, V., Mitselmakher, G., Mittleman, R., Miyakawa, O., Miyoki, S., Mohanty, S., Moreno, G., Mossavi, K., Mueller, G., Mukherjee, S., Murray, P., Myers, J., Nagano, S., Nash, T., Nayak, R., Newton, G., Nocera, F., Noel, J., Nutzman, P., Olson, T., O'Reilly, B., Ottaway, D., Ottewill, A., Ouimette, D., Overmier, H., Owen, B., Pan, Y., Papa, M., Parameshwaraiah, V., Parameswaran, A., Parameswariah, C., Pedraza, M., Penn, S., Pitkin, M., Plissi, M., Prix, R., Quetschke, V., Raab, F., Radkins, H., Rahkola, R., Rakhmanov, M., Rao, S., Rawlins, K., Ray-Majumder, S., Re, V., Redding, D., Regehr, M., Regimbau, T., Reid, S., Reilly, K., Reithmaier, K., Reitze, D., Richman, S., Riesen, R., Riles, K., Rivera, B., Rizzi, A., Robertson, D., Robertson, N., Robison, L., Roddy, S., Rollins, J., Romano, J., Romie, J., Rong, H., Rose, D., Rotthoff, E., Rowan, S., Rüdiger, A., Russell, P., Ryan, K., Salzman, I., Sandberg, V., Sanders, G., Sannibale, V., Sathyaprakash, B., Saulson, P., Savage, R., Sazonov, A., Schilling, R., Schlaufman, K., Schmidt, V., Schnabel, R., Schofield, R., Schutz, B., Schwinberg, P., Scott, S., Seader, S., Searle, A., Sears, B., Seel, S., Seifert, F., Sengupta, A., Shapiro, C., Shawhan, P., Shoemaker, D., Shu, Q., Sibley, A., Siemens, X., Sievers, L., Sigg, D., Sintes, A., Smith, J., Smith, M., Sneddon, P., Spero, R., Stapfer, G., Steussy, D., Strain, K., Strom, D., Stuver, A., Summerscales, T., Sumner, M., Sutton, P., Sylvestre, J., Takamori, A., Tanner, D., Tariq, H., Taylor, I., Taylor, R., Thorne, K., Tibbits, M., Tilav, S., Tinto, M., Tokmakov, K., Torres, C., Torrie, C., Traylor, G., Tyler, W., Ugolini, D., Ungarelli, C., Vallisneri, M., van Putten, M., Vass, S., Vecchio, A., Veitch, J., Vorvick, C., Vyachanin, S., Wallace, L., Walther, H., Ward, H., Ware, B., Watts, K., Webber, D., Weidner, A., Weiland, U., Weinstein, A., Weiss, R., Welling, H., Wen, L., Wen, S., Whelan, J., Whitcomb, S., Whiting, B., Wiley, S., Wilkinson, C., Willems, P., Williams, P., Williams, R., Willke, B., Wilson, A., Winjum, B., Winkler, W., Wise, S., Wiseman, A., Woan, G., Woods, D., Wooley, R., Worden, J., Wu, W., Yakushin, I., Yamamoto, H., Yoshida, S., Zaleski, K., Zanolin, M., Zawischa, I., Zhang, L., Zhu, R., Zotov, N., Zucker, M., and Zweizig, J.
- Published
- 2005
6. Seebeck Coefficient Measured With Differential Heat Pulses
- Author
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Zoltan, L, Wood, C, and Stapfer, G
- Subjects
Physical Sciences - Abstract
Common experimental errors reduced because pulse technique suppresses drifts in thermoelectric measurements. Differential-heat-pulse apparatus measures Seebeck coefficient in semiconductors at temperatures up to 1,900 K. Sample heated to measuring temperature in furnace. Ends of sample then differentially heated a few degrees more by lamps. Differential temperature rise and consequent Seebeck voltage measured via thermocouple leads. Because pulse technique used, errors that often arise from long-term drifts in thermoelectric measurements suppressed. Apparatus works with temperature differences of only few degrees, further increasing accuracy of coefficients obtained.
- Published
- 1986
7. Measurement of Seebeck coefficient using a light pulse
- Author
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Wood, C, Zoltan, D, and Stapfer, G
- Subjects
Instrumentation And Photography - Abstract
A high-temperature (1900 K) Seebeck coefficient apparatus is described in which small thermal gradients are generated in a sample by light pulses transmitted via light pipes. By employing an analog subtraction circuit, the Seebeck coefficient is displayed directly on an X-Y recorder. This technique presents a convenient, accurate, and rapid method for measuring the Seebeck coefficient in highly doped semiconductors as a function of temperature. The nature of the resulting display (X-Y recording) is a valuable tool in determining validity of the data. A straight line results (i.e., a minimum of hysteresis) only if all potential experimental errors are minimized. Under these conditions, the error of measurements of the Seebeck coefficient is estimated to be less than + or - 1 percent.
- Published
- 1985
- Full Text
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8. Thermoelectric conversion for space nuclear power
- Author
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Ewell, R and Stapfer, G
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Spacecraft Propulsion And Power - Abstract
A lightweight, high performance nuclear reactor power system can offer significant advantages for many space missions. Conceptual design has been completed for the SP-100, a system which utilizes many thermoelectric converters and is capable of delivering 100 kilowatts of electrical power. A reference design, using thermoelectric materials with an average figure of merit of 0.001/K and a reactor heat pipe temperature of 1500 K, is presented which has a mass of 2280 kg not including contingency. The sensitivity of system mass to changes in the configuration and thermoelectric material properties are presented
- Published
- 1982
9. The long-term performance degradation of a radioisotope thermoelectric generator using silicon germanium
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Stapfer, G and Truscello, V. C
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Spacecraft Propulsion And Power - Abstract
The successful utilization of a radioisotope thermoelectric generator (RTG) as the power source for spaceflight missions requires that the performance of such an RTG be predictable throughout the mission. Several mechanisms occur within the generator which tend to degrade the performance as a function of operating time. The impact which these mechanisms have on the available output power of an RTG depends primarily on such factors as time, temperature and self-limiting effects. The relative magnitudes, rates and temperature dependency of these various degradation mechanisms have been investigated separately by coupon experiments as well as 4-couple and 18-couple module experiments. This paper discusses the different individual mechanisms and summarizes their combined influence on the performance of an RTG. Also presented as part of the RTG long-term performance characteristics is the sensitivity of the available RTG output power to variations of the individual degradation mechanisms thus identifying the areas of greatest concern for a successful long-term mission.
- Published
- 1976
10. Sublimation behavior of silicon nitride /Si3N4/ coated silicon germanium /SiGe/ unicouples
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Stapfer, G and Truscello, V. C
- Subjects
Nonmetallic Materials - Abstract
For the Multi-Hundred Watt (MHW) Radioisotope Thermoelectric Generator (RTG), the silicon germanium unicouples are coated with silicon nitride to minimize degradation mechanisms which are directly attributable to material sublimation effects. A program is under way to determine the effective vapor suppression of this coating as a function of temperature and gas environment. The results of weight loss experiments, using Si3N4 coated hot shoes (SiMo), operating over a temperature range from 900 C to 1200 C, are analyzed and discussed. These experiments were conducted both in high vacuum and at different pressures of carbon monoxide (CO) to determine its effect on the coating. Although the results show a favorable vapor suppression at all operating temperatures, the pressure of the CO and the thickness of the coating have a decided effect on the useful lifetime of the coating.
- Published
- 1975
11. Silicon germanium technology program at JPL
- Author
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Stapfer, G and Truscello, V. C
- Subjects
Mechanical Engineering - Abstract
Review of the results of a program aimed at obtaining a better understanding of the long-term performance of a thermoelectric generator using silicon germanium. The results obtained concern the contact resistivity of the thermoelectric couples, the electrical resistance of the multifoil thermal insulation, and the application of resistance coatings to the unicouples in order to prevent the loss of output power due to internal shunting paths.
- Published
- 1974
12. Advanced thermoelectric material development at JPL
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Stapfer, G and Lockwood, A
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Spacecraft Propulsion And Power - Abstract
A large number of planetary missions under consideration for the next two decades will be using radioisotope thermoelectric generators to provide the necessary spacecraft electrical power. Performance, reliability, lifetime and cost of these RTGs are expected to be more demanding and will require the development of advanced thermoelectric materials. An advanced thermoelectric materials development program is being conducted by JPL and is the subject of this paper. Under this program, alloys of rare earth chalcogenides have been synthesized and their thermoelectric properties evaluated. The selection of specific compounds on which the program is currently concentrating is influenced by criteria such as low thermal conductivity, reasonably high operating temperatures (not less than 1000 C) and stability of the compounds. The paper discusses the rationale, approach and current status of the program. In addition, the thermoelectric and thermophysical property measurement used to evaluate the materials are described. The preliminary results and analysis of these experimental data are also given.
- Published
- 1980
13. Nuclear power source for electric propulsion
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Mondt, J. F, Stapfer, G, and Hsieh, T
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Spacecraft Propulsion And Power - Abstract
A low specific weight (20 to 40 Kg/Kwe), long life (6 to 10 year), 100 to 400 KWe nuclear electric propulsion (NEP) system can deliver 2,000 to 10,000 Kg payloads for intensive study of our solar system. The nuclear power source is about 80% of the NEP system mass, thus the NASA program is focused on developing the power source technology. Because of the long life requirements, direct thermal to electric energy conversion technology (thermionic and thermoelectric) is being pursued. In order to meet the low specific weight it is necessary to develop a 10 to 15% conversion module with a 875 K minimum heat rejection temperature and a 1675 K maximum input temperature. The thermoionic converter is about 9% efficient at these temperatures. The thermoelectric converter is limited to a 1300 K input temperature. So, the thermionic program is focused on improving the efficiency while the thermoelectric program is focused on increasing the temperature.
- Published
- 1979
14. Performance testing of thermoelectric generators including Voyager and LES 8/9 flight results
- Author
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Garvey, L and Stapfer, G
- Subjects
Spacecraft Propulsion And Power - Abstract
Several thermoelectric generators ranging in output power from 0.5 to 155 W have been completed or are undergoing testing at JPL. These generators represent a wide range of technologies, using Bi2Te3, PbTe and SiGe thermoelectric materials. Several of these generators are of a developmental type, such as HPG S/N2, and others are representative of Transit and Multi-Hundred Watt (MHW) Technology. Representative flight performance data of LES 8/9 and Voyager RTG's are presented and compared with the DEGRA computer program based on the data observed from tests of SiGe couples, modules and MHW generators.
- Published
- 1979
15. Selenide technology evaluation program at JPL
- Author
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Stapfer, G and Garvey, L
- Subjects
Spacecraft Propulsion And Power - Abstract
Results are presented for experimental and analytical investigations of the overall performance of a selenide radioisotope thermoelectric generator intended to provide the electrical power for interplanetary spaceprobes such as the Galileo mission to Jupiter. The discussion focuses on technology areas of concern, electrical properties of the selenide thermoelectric materials used, and thermal conductivity of these materials for superior performance. It is shown that the selenide thermoelectric materials offer the advantage of high conversion efficiency. The long-life requirement on the power system for the Galileo mission necessitates proper design, known fabrication techniques, and reproducible assembly techniques in order to ensure stability of the thermoelectric properties. However, the thermophysical properties - sublimation and creep - of the p-material remains an area of considerable concern.
- Published
- 1978
16. Analytical predictions of selenide RTG power degradation
- Author
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Noon, E. L, Stapfer, G, and Raag, V
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Energy Production And Conversion - Abstract
A mathematical model for the performance and degradation analysis of an RTG using the newly developed selenide thermoelectric materials has been developed at JPL. The computerized model is quite comprehensive and enables the accurate detailing of the electrical and thermal effects that take place within the thermocouple under any desired set of operation conditions, including heat input, ambient temperature and load conditions. The paper discusses the logic flow of the computer model and presents the time and temperature dependent results for various degradation mechanisms and rates as they have been established to date.
- Published
- 1978
17. Development of the data base for a degradation model of a selenide RTG
- Author
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Stapfer, G and Truscello, V. C
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Spacecraft Propulsion And Power - Abstract
The paper is concerned with the evaluation of the materials used in a selenide radioisotope thermoelectric generator (RTG). These materials are composed of n-type gadolinium selenide and n-type copper selenide. A three-fold evaluation approach is being used: (1) the study of the rate of change of the thermal conductivity of the material, (2) the investigation of the long-term stability of the material's Seebeck voltage and electrical resistivity under current and temperature gradient conditions, and (3) determination of the physical behavior and compatibility of the material with surrounding insulation at elevated temperatures. Programmatically, the third category of characteristic evaluation is being emphasized.
- Published
- 1977
18. A model to predict the degradation of a SiGe thermopile.
- Author
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Stapfer, G and Truscello, V
- Subjects
Nuclear Engineering - Abstract
Discussion of the various phenomena which affect the available output power of a typical radioisotope thermoelectric generator (RTG), including estimates of the magnitude of these effects. Power degradation, as well as the corresponding changes in operating temperature, are calculated by means of a computer code which systematically accounts for the time- and temperature-dependent variables. A model for predicting available output power of an RTG is developed which includes changes in performance due to fuel decay, alteration of bulk thermoelectric properties, changes in electrode contacts, geometry changes due to material sublimation, and degradation of the thermal insulation.
- Published
- 1972
19. Preliminary testing of a SNAP-19 TAGS RTG in support of the Pioneer F and G missions.
- Author
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Stapfer, G
- Subjects
Nuclear Engineering - Abstract
This paper presents the results of a preliminary performance evaluation of the SNAP-19 TAGS thermoelectric generator which was selected as the power source for the Pioneer Space Flight Mission. The performance of the SNAP-19 generator was evaluated at various input powers and fin-root temperatures. Results of this evaluation are analyzed and discussed. Tests were also performed to provide the Pioneer Flight Project Management with applicable data such as generator thermal dynamic behavior during launch and prior to deployment. These special tests measure generator performance as a function of fin-root temperature and the dynamic frequency response of the generator.
- Published
- 1972
20. Silicon-germanium technology program of the Jet Propulsion Laboratory.
- Author
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De Winter, F and Stapfer, G
- Subjects
Nuclear Engineering - Abstract
The outer planetary exploration missions studied by the Jet Propulsion Laboratory require silicon-germanium radioisotope thermoelectric generators (RTGs) in which the factors of safety are as low as is compatible with the reliable satisfaction of the power needs. Work on silicon germanium sublimation performed at the Jet Propulsion Laboratory is presented. Analytical modeling work on the solid-diffusion process involved in the steady-state (free) sublimation of silicon germanium is described. Analytical predictions are made of the sublimation suppression which can be achieved by using a cover gas. A series of accelerated (high-temperature) tests which were performed on simulated hardware (using four SiGe couples) to study long-term sublimation and reaction mechanisms are also discussed.
- Published
- 1972
21. The thermoelectric generator test program at JPL.
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Stapfer, G and Rouklove, P
- Subjects
Propulsion Systems - Abstract
Discussion of the test results and analysis performed on data obtained from eight thermoelectric generators exhibiting a total combined operating time of about 21 years. Three (3) SNAP-19 type generators are discussed. Generator SN-20, the engineering model of the units presently operating on the Nimbus S/C, has been in operation for over 4 years and has shown drastic degradation after losing the internal cover gas. Generator SN-21, with more than four years of operating time, is operated in an air environment. The performance of this generator appears predictable and stable. For the last 2 years of operation generator degradation has been negligible. Generator SN-31, which utilizes the TAGS material for the P thermoelectric leg, is similar in design to the units to be used on the Pioneer S/C and has operated for over two years in an all-argon atmosphere.
- Published
- 1972
22. The long term behavior of SNAP-19 generators which use the TAGS thermoelectric material
- Author
-
Stapfer, G and Truscello, V
- Subjects
Nuclear Engineering - Abstract
SNAP 19 TAGS thermoelectric generator life tests at high temperature in Ar, predicting long term performance including thermoelectric material and isotope fuel decay effects
- Published
- 1971
23. Performance testing and evaluation of a high temperature silicon germanium thermoelectric generator
- Author
-
Stapfer, G and Truscello, V
- Subjects
Nuclear Engineering - Abstract
Performance tests of high temperature silicon- germanium alloy thermoelectric generator for outer planet mission spacecraft
- Published
- 1971
24. Thermionic converter life-test program
- Author
-
Stapfer, G
- Subjects
Auxiliary Systems - Abstract
Solar energy thermionic converter life test program and equipment, noting failure due to loss of intraelectrode Cs
- Published
- 1969
25. Electrical testing of a six-converter generator.
- Author
-
Shimada, K and Stapfer, G
- Subjects
Auxiliary Systems - Abstract
Electrical testing of six converter solar energy thermionic generator, discussing overheating and dual current mode anomalies
- Published
- 1968
26. The development and use of an integrated thermoelectric life and performance testing system.
- Author
-
Selwitz, L and Stapfer, G
- Subjects
Facilities, Research, And Support - Abstract
Integrated thermoelectric life and performance testing system including environmental chambers, automatic control systems and central data scanning and recording system
- Published
- 1966
27. High temperature material interactions of thermoelectric systems using silicon germanium.
- Author
-
Stapfer, G and Truscello, V. C
- Subjects
Nuclear Engineering - Abstract
The efficient use of silicon germanium thermoelectric material for radioisotope thermoelectric generators (RTG) is achieved by operation at relatively high temperatures. The insulation technique which is most appropriate for this application uses multiple layers of molybdenum foil and astroquartz. Even so, the long term operation of these materials at elevated temperatures can cause material interaction to occur within the system. To investigate these material interactions, the Jet Propulsion Laboratory is currently testing a number of thermoelectric modules which use four silicon germanium thermoelectric couples in conjunction with the multifoil thermal insulation. The paper discusses the results of the ongoing four-couple module test program and correlates test results with those of a basic material test program.
- Published
- 1973
28. The behavior of xenon when used as a fill-gas in a silicon germanium radioisotope thermoelectric generator.
- Author
-
De Winter, F and Stapfer, G
- Subjects
Nuclear Engineering - Published
- 1973
29. The design of a nuclear power supply with a 50 year life expectancy: the JPL Voyager's SiGe MHW RTG.
- Author
-
de Winter, F., Stapfer, G., and Medina, E.
- Abstract
Between 25 and 30 years ago, the IECEC Proceedings carried a series of papers by the present authors and other members of a JPL team on the problems and the desirable design features associated with the MHW RTGs to be used to power JPL's Voyager I and II spacecraft. The Voyager I and II spacecraft successfully completed their original 12 year missions 10 years ago and are at distances of over 55 AU and 70 AU from the sun. The power systems worked almost precisely as predicted. The Voyager spacecraft seem to have several decades of life left to make measurements outside the solar system. This paper gives a technical overview of the design process and problems [ABSTRACT FROM PUBLISHER]
- Published
- 2000
- Full Text
- View/download PDF
30. Development of segmented thermoelectric multicouple converter technology.
- Author
-
Fleurial, J.-P., Johnson, K., Mondt, J., Sakamoto, J., Snyder, J., Chen-Kuo Huang, Blair, R., Stapfer, G., Caillat, T., Frye, P., Determan, W., Heshmatpour, B., Brooks, M., and Tuttle, K.
- Published
- 2006
- Full Text
- View/download PDF
31. Pathologic Alterations of the Kidneys and Heart in Patients with Ankylosing Spondylitis.
- Author
-
Jung, O., Stapfer, G., Ditting, T., Geiger, H., and Lange, U.
- Subjects
- *
KIDNEY diseases , *HEART diseases , *ANKYLOSING spondylitis , *ANKYLOSIS , *SPONDYLITIS - Abstract
Objective: The occurrence of a variety of pathological lesions of the kidneys and heart have been described in patients with ankylosing spondylitis (AS). The frequency of these alterations and whether they are specific for AS has been discussed controversially. Methods: Outpatients with AS were studied to determine the frequency of cardiac and renal alterations and to assess the associated clinical and demographic factors. Results: A total of 77 patients with AS participated in the study. The majority were male (84.4%) and HLA-B27 positive (84.4%). Mean age was 48.3 ± 1.5 years and mean duration of diagnosed AS was 15.4 ± 1.2 years. Hypertension was present in 36.4% and diabetes mellitus in 13.0%. Impaired renal function (defined by a decrease in GFR) combined with markers of kidney damage suspective for chronic kidney disease were present in 3 patients (3.9%). Proteinuria was present in 10 patients (12.9%) with a proteinuria of >1,000 mg/day in one and a proteinuria of >1,000 mg/day in 9 patients. Within the proteinuric patients 5 had concomitant diabetes mellitus and 7 patients had concomitant systemic hypertension. Pathologic alterations of the heart were found in 25 patients (37.3%). Echocardiographic abnormalities were present in 20 patients (including aortic, mitral and tricuspid insufficiency, left ventricular dysfunction, pericardial effusion). Electrocardiographic abnormalities were present in 12 patients (including atrioventricular, left and right branch block as well as sinus bradycardia). Patients with cardiac abnormalities were older (54.2 ± 2.9 vs. 44.9 ± 1.7 years, P < 0.01) and had a longer duration of diagnosed AS (20.6 ± 2.1 vs. 13.9 ± 1.6 years, P < 0.02) as compared to non-affected patients. Conclusions: In our study, cardiac abnormalities were frequently seen in patients with AS, while renal disease was more rare and might be due to diseases not related to AS, e.g. diabetes mellitus, in most of patients as well. It therefore appears questionable -- in contrast to cardiac involvement -- whether chronic kidney disease is part of the extraskeletal manifestations seen in AS, or at least that AS has a high impact on renal integrity. [ABSTRACT FROM AUTHOR]
- Published
- 2004
32. Copper-selenide system, P-Type TPM-217
- Author
-
Stapfer, G
- Published
- 1977
- Full Text
- View/download PDF
33. Testing of the SNAP-27 ten-couple modules
- Author
-
Stapfer, G
- Published
- 1969
- Full Text
- View/download PDF
34. Behavior of xenon when used as a fill-gas in a silicon germanium radioisotope thermoelectric generator
- Author
-
Stapfer, G
- Published
- 1973
35. Silicon-germanium technology program of the Jet Propulsion Laboraory
- Author
-
Stapfer, G
- Published
- 1972
36. PRELIMINARY TESTING OF A SNAP-19 TAGS RTG IN SUPPORT OF THE PIONEER F AND G MISSIONS.
- Author
-
Stapfer, G
- Published
- 1970
37. The influence of the SARS-CoV-2 lockdown on patients with inflammatory rheumatic diseases on their adherence to immunomodulatory medication: a cross sectional study over 3 months in Germany.
- Author
-
Hasseli R, Müller-Ladner U, Keil F, Broll M, Dormann A, Fräbel C, Hermann W, Heinmüller CJ, Hoyer BF, Löffler F, Özden F, Pfeiffer U, Saech J, Schneidereit T, Schlesinger A, Schwarting A, Specker C, Stapfer G, Steinmüller M, Storck-Müller K, Strunk J, Thiele A, Triantafyllias K, Vagedes D, Wassenberg S, Wilden E, Zeglam S, and Schmeiser T
- Subjects
- Adult, Antirheumatic Agents therapeutic use, Cross-Sectional Studies, Female, Germany, Humans, Immunologic Factors therapeutic use, Male, Middle Aged, SARS-CoV-2, COVID-19 prevention & control, Drug Prescriptions statistics & numerical data, Medication Adherence statistics & numerical data, Practice Patterns, Physicians' statistics & numerical data, Quarantine statistics & numerical data, Rheumatic Diseases drug therapy
- Abstract
Objectives: To evaluate the influence of the SARS-CoV-2 pandemic on the adherence of patients with inflammatory rheumatic diseases (IRD) to their immunomodulatory medication during the three-month lockdown in Germany., Methods: From 16th March until 15th June 2020, IRD patients from private practices and rheumatology departments were asked to answer a questionnaire addressing their behaviour with respect to their immunomodulating therapy. Eight private practices and nine rheumatology departments that included rheumatology primary care centres and university hospitals participated. A total of 4252 questionnaires were collected and evaluated., Results: The majority of patients (54%) were diagnosed with RA, followed by psoriatic arthritis (14%), ankylosing spondylitis (10%), connective tissue diseases (12%) and vasculitides (6%). Most of the patients (84%) reported to continue their immunomodulatory therapy. Termination of therapy was reported by only 3% of the patients. The results were independent from the type of IRD, the respective immunomodulatory therapy and by whom the patients were treated (private practices vs rheumatology departments). Younger patients (<60 years) reported just as often as older patients to discontinue their therapy., Conclusion: The data show that most of the patients continued their therapy in spite of the pandemic. A significant change in behaviour with regard to their immunomodulatory therapy was not observed during the three months of observation. The results support the idea that the immediate release of recommendations of the German Society of Rheumatology were well received, supporting the well-established physician-patient relationship in times of a crisis., (© The Author(s) 2021. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
- Full Text
- View/download PDF
38. Pathologic alterations of the heart and the kidney in patients with ankylosing spondylitis.
- Author
-
Lange U, Stapfer G, Ditting T, Geiger H, Teichmann J, Müller-Ladner U, and Jung O
- Subjects
- Adult, Electrocardiography, Female, Heart Diseases complications, Heart Diseases pathology, Humans, Kidney pathology, Kidney Diseases complications, Kidney Diseases pathology, Male, Middle Aged, Myocardium pathology, Heart Diseases diagnosis, Kidney Diseases diagnosis, Spondylitis, Ankylosing complications
- Abstract
Background: The occurrence of a variety of pathological lesions of the heart and kidneys have been described in patients with ankylosing spondylitis (AS). The frequency of these alterations and whether they are specific for AS has been discussed controversially. -, Methods: Outpatients with AS were studied to determine the frequency of cardiac and renal alterations and to assess the associated clinical and demographic factors. -, Results: A total of 77 patients with AS participated in the study (male 84.4%, mean age 48.3 +/- 1.5 years, mean duration of disease 15.4 +/- 1.2 years). Hypertension was present in 36.4% and diabetes mellitus in 13.0%. Impaired renal function (defined by a decrease in GFR) combined with markers of kidney damage suspective for chronic kidney disease were present in 3 patients (3.9%). Pathologic alterations of the heart were found in 25 patients (37.3%). Echocardiographic abnormalities were present in 20 patients (e.g. aortic and mitral insufficiency). Electrocardiographic abnormalities were present in 12 patients (e.g. atrioventricular, left and right branch block). Patients with cardiac abnormalities were older (54.2 +/- 2.9 vs. 44.9 +/- 1.7 years) and had a longer duration of disease (20.6 +/- 2.1 vs. 13.9 +/- 1.6 years) as compared to non-affected patients. -, Conclusion: In our study, cardiac abnormalities were frequently seen in patients with AS, while renal disease was more rare and might be due to diseases not related to AS in most of patients. In contrast to cardiac involvement, it therefore appears questionable, that chronic kidney disease is part of the extraskeletal manifestations, or at least that AS has a high impact on renal integrity.
- Published
- 2007
39. Limits on gravitational-wave emission from selected pulsars using LIGO data.
- Author
-
Abbott B, Abbott R, Adhikari R, Ageev A, Allen B, Amin R, Anderson SB, Anderson WG, Araya M, Armandula H, Ashley M, Asiri F, Aufmuth P, Aulbert C, Babak S, Balasubramanian R, Ballmer S, Barish BC, Barker C, Barker D, Barnes M, Barr B, Barton MA, Bayer K, Beausoleil R, Belczynski K, Bennett R, Berukoff SJ, Betzwieser J, Bhawal B, Bilenko IA, Billingsley G, Black E, Blackburn K, Blackburn L, Bland B, Bochner B, Bogue L, Bork R, Bose S, Brady PR, Braginsky VB, Brau JE, Brown DA, Bullington A, Bunkowski A, Buonanno A, Burgess R, Busby D, Butler WE, Byer RL, Cadonati L, Cagnoli G, Camp JB, Cantley CA, Cardenas L, Carter K, Casey MM, Castiglione J, Chandler A, Chapsky J, Charlton P, Chatterji S, Chelkowski S, Chen Y, Chickarmane V, Chin D, Christensen N, Churches D, Cokelaer T, Colacino C, Coldwell R, Coles M, Cook D, Corbitt T, Coyne D, Creighton JD, Creighton TD, Crooks DR, Csatorday P, Cusack BJ, Cutler C, D'Ambrosio E, Danzmann K, Daw E, DeBra D, Delker T, Dergachev V, DeSalvo R, Dhurandhar S, Di Credico A, Díaz M, Ding H, Drever RW, Dupuis RJ, Edlund JA, Ehrens P, Elliffe EJ, Etzel T, Evans M, Evans T, Fairhurst S, Fallnich C, Farnham D, Fejer MM, Findley T, Fine M, Finn LS, Franzen KY, Freise A, Frey R, Fritschel P, Frolov VV, Fyffe M, Ganezer KS, Garofoli J, Giaime JA, Gillespie A, Goda K, González G, Gossler S, Grandclément P, Grant A, Gray C, Gretarsson AM, Grimmett D, Grote H, Grunewald S, Guenther M, Gustafson E, Gustafson R, Hamilton WO, Hammond M, Hanson J, Hardham C, Harms J, Harry G, Hartunian A, Heefner J, Hefetz Y, Heinzel G, Heng IS, Hennessy M, Hepler N, Heptonstall A, Heurs M, Hewitson M, Hild S, Hindman N, Hoang P, Hough J, Hrynevych M, Hua W, Ito M, Itoh Y, Ivanov A, Jennrich O, Johnson B, Johnson WW, Johnston WR, Jones DI, Jones L, Jungwirth D, Kalogera V, Katsavounidis E, Kawabe K, Kawamura S, Kells W, Kern J, Khan A, Killbourn S, Killow CJ, Kim C, King C, King P, Klimenko S, Koranda S, Kötter K, Kovalik J, Kozak D, Krishnan B, Landry M, Langdale J, Lantz B, Lawrence R, Lazzarini A, Lei M, Leonor I, Libbrecht K, Libson A, Lindquist P, Liu S, Logan J, Lormand M, Lubinski M, Lück H, Lyons TT, Machenschalk B, MacInnis M, Mageswaran M, Mailand K, Majid W, Malec M, Mann F, Marin A, Márka S, Maros E, Mason J, Mason K, Matherny O, Matone L, Mavalvala N, McCarthy R, McClelland DE, McHugh M, McNabb JW, Mendell G, Mercer RA, Meshkov S, Messaritaki E, Messenger C, Mitrofanov VP, Mitselmakher G, Mittleman R, Miyakawa O, Miyoki S, Mohanty S, Moreno G, Mossavi K, Mueller G, Mukherjee S, Murray P, Myers J, Nagano S, Nash T, Nayak R, Newton G, Nocera F, Noel JS, Nutzman P, Olson T, O'Reilly B, Ottaway DJ, Ottewill A, Ouimette D, Overmier H, Owen BJ, Pan Y, Papa MA, Parameshwaraiah V, Parameswariah C, Pedraza M, Penn S, Pitkin M, Plissi M, Prix R, Quetschke V, Raab F, Radkins H, Rahkola R, Rakhmanov M, Rao SR, Rawlins K, Ray-Majumder S, Re V, Redding D, Regehr MW, Regimbau T, Reid S, Reilly KT, Reithmaier K, Reitze DH, Richman S, Riesen R, Riles K, Rivera B, Rizzi A, Robertson DI, Robertson NA, Robison L, Roddy S, Rollins J, Romano JD, Romie J, Rong H, Rose D, Rotthoff E, Rowan S, Rüdiger A, Russell P, Ryan K, Salzman I, Sandberg V, Sanders GH, Sannibale V, Sathyaprakash B, Saulson PR, Savage R, Sazonov A, Schilling R, Schlaufman K, Schmidt V, Schnabel R, Schofield R, Schutz BF, Schwinberg P, Scott SM, Seader SE, Searle AC, Sears B, Seel S, Seifert F, Sengupta AS, Shapiro CA, Shawhan P, Shoemaker DH, Shu QZ, Sibley A, Siemens X, Sievers L, Sigg D, Sintes AM, Smith JR, Smith M, Smith MR, Sneddon PH, Spero R, Stapfer G, Steussy D, Strain KA, Strom D, Stuver A, Summerscales T, Sumner MC, Sutton PJ, Sylvestre J, Takamori A, Tanner DB, Tariq H, Taylor I, Taylor R, Taylor R, Thorne KA, Thorne KS, Tibbits M, Tilav S, Tinto M, Tokmakov KV, Torres C, Torrie C, Traylor G, Tyler W, Ugolini D, Ungarelli C, Vallisneri M, van Putten M, Vass S, Vecchio A, Veitch J, Vorvick C, Vyachanin SP, Wallace L, Walther H, Ward H, Ware B, Watts K, Webber D, Weidner A, Weiland U, Weinstein A, Weiss R, Welling H, Wen L, Wen S, Whelan JT, Whitcomb SE, Whiting BF, Wiley S, Wilkinson C, Willems PA, Williams PR, Williams R, Willke B, Wilson A, Winjum BJ, Winkler W, Wise S, Wiseman AG, Woan G, Wooley R, Worden J, Wu W, Yakushin I, Yamamoto H, Yoshida S, Zaleski KD, Zanolin M, Zawischa I, Zhang L, Zhu R, Zotov N, Zucker M, Zweizig J, Kramer M, and Lyne AG
- Abstract
We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars.
- Published
- 2005
- Full Text
- View/download PDF
40. Opposite regulation of tissue factor expression by calcineurin in monocytes and endothelial cells.
- Author
-
Hölschermann H, Rascher C, Oelschläger C, Stapfer G, Langenstein A, Staubitz A, Maus U, Tillmanns H, Bang H, and Haberbosch W
- Subjects
- Calcineurin Inhibitors, Cells, Cultured, Cyclosporine pharmacology, Endothelium, Vascular cytology, Endothelium, Vascular drug effects, Endothelium, Vascular enzymology, Enzyme Activation drug effects, Enzyme Inhibitors pharmacology, Gene Expression Regulation drug effects, Humans, Monocytes drug effects, Monocytes enzymology, Peptidylprolyl Isomerase metabolism, RNA, Messenger antagonists & inhibitors, RNA, Messenger biosynthesis, Thromboplastin genetics, Transcriptional Activation drug effects, Umbilical Veins, Calcineurin physiology, Endothelium, Vascular metabolism, Monocytes metabolism, Thromboplastin antagonists & inhibitors, Thromboplastin biosynthesis
- Abstract
Tissue factor (TF), the primary initiator of blood coagulation with structural homology to the cytokine receptor family, has been implicated in various vascular processes including metastasis, angiogenesis, and atherosclerosis. Within the vasculature, monocytes and endothelial cells (EC) can be activated to synthesize TF depending on the induction of NF-kappaB. Despite the undisputed value of cyclosporin A (CsA) as an immunosuppressant, problems have emerged due to induction of vascular changes by a poorly understood mechanism. We demonstrate that CsA has opposite effects on TF gene expression, inhibiting NF-kappaB-mediated TF gene transcription in monocytes but enhancing it in EC. To test whether CsA binding proteins (cyclophilins) can mediate these CsA effects we used a nonimmunosuppressant analog of CsA that binds to cyclophilins but does not inhibit the Ca2+/calmodulin-dependent phosphatase calcineurin (Cn). This drug lacked regulatory function for NF-kappaB and TF expression suggesting that Cn is responsible for the inverse gene regulation. The key function of Cn was supported by experiments demonstrating that other phosphatase inhibitors also either positively or negatively regulated NF-kappaB in monocytes and EC. Calcineurin was demonstrated to regulate NF-kappaB activation at the level of IkappaBalpha degradation, because agonist-induced phosphorylation and subsequent degradation of IkappaBalpha is prevented by Cn inhibitors in monocytes but enhanced in EC. These data identify Cn as an opposite regulator in generating transcriptionally active NF-kappaB, and they confirm the presumption that the ability of Cn to participate in NF-kappaB transactivation is not T cell specific.
- Published
- 2001
- Full Text
- View/download PDF
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