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1. The thermal neutron capture cross section of the radioactive isotope $^{60}$Fe

Author

Heftrich, T., Bichler, M., Dressler, R., Eberhardt, K., Endres, A., Glorius, J., Göbel, K., Hampel, G., Heftrich, M., Käppeler, F., Lederer, C., Mikorski, M., Plag, R., Reifarth, R., Stieghorst, C., Schmidt, S., Schumann, D., Slavkovská, Z., Sonnabend, K., Wallner, A., Weigand, M., Wiehl, N., and Zauner, S.

Subjects
Nuclear Experiment, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

50% of the heavy element abundances are produced via slow neutron capture reactions in different stellar scenarios. The underlying nucleosynthesis models need the input of neutron capture cross sections. One of the fundamental signatures for active nucleosynthesis in our galaxy is the observation of long-lived radioactive isotopes, such as $^{60}$Fe with a half-life of $2.60\times10^6$ yr. To reproduce this $\gamma$-activity in the universe, the nucleosynthesis of $^{60}$Fe has to be understood reliably. A $^{60}$Fe sample produced at the Paul-Scherrer-Institut was activated with thermal and epithermal neutrons at the research reactor at the Johannes Gutenberg-Universit\"at Mainz. The thermal neutron capture cross section has been measured for the first time to $\sigma_{\text{th}}=0.226 \ (^{+0.044}_{-0.049})$ b. An upper limit of $\sigma_{\text{RI}} < 0.50$ b could be determined for the resonance integral. An extrapolation towards the astrophysicaly interesting energy regime between $kT$=10 keV and 100 keV illustrates that the s-wave part of the direct capture component can be neglected., Comment: 8 pages, 8 Figs, accepted for publication at PRC

Published
2015
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2. V2:Performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz

Author

Karch, J., Sobolev, Yu., Beck, M., Eberhardt, K., Hampel, G., Heil, W., Kieser, R., Reich, T., Trautmann, N., and Ziegner, M.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

The performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz with a maximum peak energy of 10 MJ is described. The solid deuterium converter with a volume of V=160 cm3 (8 mol), which is exposed to a thermal neutron fluence of 4.5x10^13 n/cm2, delivers up to 550 000 UCN per pulse outside of the biological shield at the experimental area. UCN densities of ~ 10/cm3 are obtained in stainless steel bottles of V ~ 10 L resulting in a storage efficiency of ~20%. The measured UCN yields compare well with the predictions from a Monte Carlo simulation developed to model the source and to optimize its performance for the upcoming upgrade of the TRIGA Mainz into a user facility for UCN physics., Comment: 23 pages, 8 figures

Published
2013
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3. Cubic boron nitride: a new prospective material for ultracold neutron application

Author

Sobolev, Yu., Lauer, Th., Borisov, Yu., Daum, M., Fresne, N. du, Goeltl, L., Hampel, G., Heil, W., Knecht, A., Keunecke, M., Kratz, J. V., Lang, T., Meister, M., Plonka-Spehr, Ch., Pokotilovski, Yu., Reichert, P., Schmidt, U., Krist, Th., Wiehl, N., and Zenner, J.

Subjects
Nuclear Experiment
Abstract

For the first time, the neutron optical wall-potential of natural cubic boron nitride (cBN) was measured at the ultracold neutron (UCN) source of the research reactor TRIGA Mainz using the time-of-flight method (TOF). The samples investigated had a wall-potential of (305 +/- 15) neV. This value is in good agreement with the result extracted from neutron reflectometry data and theoretical expectations. Because of its high critical velocity for UCN and its good dielectric characteristics, cubic boron nitride coatings (isotopically enriched) will be useful for a number of applications in UCN experiments.

Published
2009
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4. An Improved Neutron Electric Dipole Moment Experiment

Author

Kuźniak, M., Altarev, I., Ban, G., Bison, G., Bodek, K., Burghoff, M., Daum, M., Eberhardt, K., Fierlinger, P., Gutsmiedl, E., Hampel, G., Heil, W., Henneck, R., Khomutov, N., Kirch, K., Kistryn, St., Knappe-Grueneberg, S., Knecht, A., Knowles, P., Kratz, J. V., Lauer, T., Lauss, B., Lefort, T., Mtchedlishvili, A., Naviliat-Cuncic, O., Paul, S., Pazgalev, A. S., Petzold, G., Plonka-Spehr, C., Quéméner, G., Rebreyend, D., Roccia, S., Rogel, G., Sander-Thoemmes, T., Schnabel, A., Severijns, N., Sobolev, Yu., Stoepler, R., Trahms, L., Tur, M., Weis, A., Wiehl, N., Zejma, J., and Zsigmond, G.

Subjects
Nuclear Experiment
Abstract

A new measurement of the neutron EDM, using Ramsey's method of separated oscillatory fields, is in preparation at the new high intensity source of ultra-cold neutrons (UCN) at the Paul Scherrer Institute, Villigen, Switzerland (PSI). The existence of a non-zero nEDM would violate both parity and time reversal symmetry and, given the CPT theorem, might lead to a discovery of new CP violating mechanisms. Already the current upper limit for the nEDM (|d_n|<2.9E-26 e.cm) constrains some extensions of the Standard Model. The new experiment aims at a two orders of magnitude reduction of the experimental uncertainty, to be achieved mainly by (1) the higher UCN flux provided by the new PSI source, (2) better magnetic field control with improved magnetometry and (3) a double chamber configuration with opposite electric field directions. The first stage of the experiment will use an upgrade of the RAL/Sussex/ILL group's apparatus (which has produced the current best result) moved from Institut Laue-Langevin to PSI. The final accuracy will be achieved in a further step with a new spectrometer, presently in the design phase., Comment: Flavor Physics & CP Violation Conference, Taipei, 2008

Published
2008

7. RF power dependence study of large area YBCO thin films

Author

Ma, Zhengxiang, Obaldia, E. de, Hampel, G., Polakos, P., Mankiewich, P., Batlogg, B., Prusseit, W., Kinder, H., Anderson, A., Oates, D.E., Ono, R., and Beall, J.

Subjects
Thin films -- Research, High temperature superconductors -- Research, Business, Electronics, Electronics and electrical industries
Abstract

A study was conducted on the radio frequency power dependence of large area YBCO thin films on LaAlO3 substrates. A coplanar waveguide resonator method was employed in determining the changes of inductance and loss vs circulating microwave currents. Correlations were observed between the radio frequency power dependence and penetration depth, crystal structures and other film properties.

Published
1997

8. Characterization of the terminal column of TRIGA Mark II reactor of Mainz through of alanine pellets

Author

GALLO, Salvatore, Schmitz T, BARTOLOTTA, Antonio, COLLURA, Giorgio, Hampel G, PANZECA, Salvatore, MARRALE, Maurizio, Gallo S, Schmitz T, Bartolotta A, Collura G, Hampel G, Panzeca S, and Marrale M

Subjects
Settore FIS/01 - Fisica Sperimentale, MC simulation, Alanine, ESR, EPR, Neutron, Fluka, Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)
Abstract

We have studied the ESR response of alanine pellets with and without gadolinium exposed to the thermal column of the TRIGA Mark II research reactor at the University of Mainz (Germany). The choice of Gd as additive nucleus is due to its very high capture cross section to thermal neutrons and to the possibility for secondary particles produced after interaction with thermal neutrons of releasing their energy in the neighborhood of the reaction site. In particular, it was found that low concentration (5% by weight) of Gd brings about a neutron sensitivity enhancement of more than 10 times without heavily reducing tissue equivalence. Monte Carlo (MC) simulations of both response of alanine and Gd-alanine pellets with FLUKA code were performed and the results were compared with the experimental values.

Published
2017

9. Neutron velocity distribution from a superthermal solid 2H2 ultracold neutron source

Author

Altarev, I., Daum, M., Frei, A., Gutsmiedl, E., Hampel, G., Hartmann, F., Heil, W., Knecht, A., Kratz, J., Lauer, T., Meier, M., Paul, S., Schmidt, U., Sobolev, Y., Wiehl, N., and Zsigmond, G.

Abstract

We have determined for the first time the velocity distribution of neutrons from a solid 2H2 ultracold neutron (UCN) source. The spectrum rises sharply above 4.5m/s and has a maximum around 7m/s after transport in an 8m long guide. The number of neutrons in the UCN velocity range (< 7m/s) may be increased by a factor of two by placing the experiment 1m above the UCN source level

Published
2018

10. Combined fit of spectrum and composition data as measured by the Pierre Auger Observatory (vol 4, 038, 2017)

Author

Aab, A., Abreu, P., Aglietta, M., Samarai, Al, Albuquerque, I., Allekotte, I. F. M., Almela, I., Alvarez, Castillo, Alvarez-Muniz, J., Anastasi, Jessica, Anchordoqui, G. A., Rada, B., Ringa, S., Aramo, C., Arqueros, F., Arsene, N., Asorey, H., Assis, P., Aublin, J., Avila, G., Badescu, A. M., Balaceanu, A., Barreira, Luz, Beatty, R. J., Becker, J. J., Bellido, K. H., Berat, J. A., Bertaina, C., Bertou, M. E., Biermann, X., Billoir, P. L., Biteau, P., Blaess, J., Blanco, S. G., Blazek, A., Bleve, J., Bohacova, C., Boncioli, M., Bonifazi, D., Borodai, C., Botti, N., Brack, A. M., Brancus, J., Bretz, I., Bridgeman, T., Briechle, A., Buchholz, F. L., Bueno, P., Buitink, A., Buscemi, S., Caballero-Mora, M., Caccianiga, K. S., Cancio, L., Canfora, A., Caramete, F., Caruso, L., Castellina, R., Cataldi, Alessia, Cazon, G., Chavez, L., Chinellato, A. G., Chudoba, J. A., Clay, J., Colalillo, R. W., Coleman, R., Collica, A., Coluccia, L., Conceicao, M. R., Contreras, R., Cooper, F., Coutu, M. J., Covault, S., Cronin, C. E., D'Amico, J., Daniel, S., Dasso, B., Daumiller, S., Dawson, K., B. R., Almeida, De, Costa, ROSANNA MARIA STEFANIA, Jong, De, S. J., Mauro, De, de Mello Neto, J. R. T., Mitri, De, Oliveira, De, Souza, De, Debatin, V., Deligny, J., DI GIULIO, Augusto, Matteo, Di, Diaz, Castro, Diogo, M. L., Dobrigkeit, F., D'Olivo, C., Dorosti, J. C., Dos, Anjos, Dova, R. C., Dundovic, M. T., Ebr, A., Engel, J., Erdmann, R., Erfani, M., Escobar, M., Espadanal, C. O., Etchegoyen, J., Falcke, A., Farrar, H., Fauth, G., Fazzini, A. C., Fick, N., Figueira, B., Filipcic, J. M., Fratu, A., Freire, O., Fujii, M. M., Fuster, T., Gaior, A., Garcia, R., Garcia-Pinto, B., Gate, D., Gemmeke, F., Gherghel-Lascu, H., Ghia, A., Giaccari, P. L., Giammarchi, U., Giller, M., LAS CASAS, Maria Carmela, Glaser, D. G., Golup, C., Gomez, Berisso, Gomez, Vitale, Gonzalez, P. F., Gorgi, N., Gorham, A., Grillo, P., Grubb, A. F., Guarino, T. D., Guedes, F., Hampel, G. P., Hansen, M. R., Harari, P., Harrison, D., Harton, T. A., Haungs, J. L., Hebbeker, A., Heck, T., Heimann, D., Herve, P., Hill, A. E., Hojvat, G. C., Holt, C., Homola, E., Hor, P., J. R., El, Horvath, P., Hrabovsky, M., Huege, T., Hulsman, J., Insolia, A., Isar, P. G., J, T, Jansen, I., Johnsen, S., Josebachuili, J. A., Kaapa, M., Kambeitz, A., Kampert, O., Katkov, K. H., Keilhauer, I., Kemp, B., Kemp, E., Kieckhafer, J., Klages, R. M., Kleifges, H. O., Kleinfeller, M., Krause, J., Krohm, R., Kuempel, N., Mezek, D., Kukec, G., Kunka, N., Awad, Kuotb, A., Lahurd, D., Lauscher, M., Legumina, R., Leigui de Oliveira, Letessier-Selvon, M. A., Lhenry-Yvon, A., Link, I., Lopes, K., Lopez, L., Lopez, Casado, Luce, A., Lucero, Q., Malacari, A., Mallamaci, M., AYSAR M. M., Yasin, At, D., Mantsch, P., Mariazzi, A. G., Maris, I. C., Marsella, G., Martello, D., Martinez, H., Martinez, Bravo, Masias, Meza, Mathes, J. J., Mathys, H. J., Matthews, S., Matthews, J., Matthiae, J. A. J., Mayotte, G., Mazur, E., Medina, P. O., Medina-Tanco, C., Melo, G., Menshikov, D., Micheletti, A., Middendorf, M. I., Minaya, L., Miramonti, I. A., Mitrica, L., Mockler, B., Mollerach, D., Montanet, S., Morello, F., Mostafa, C., Mueller, M., Mueller, A. L., Muller, G., Mueller, M. A., Mussa, S., Naranjo, R., Nellen, I., Nguyen, L., Niculescu-Oglinzanu, P. H., Niechciol, M., Niemietz, M., Niggemann, L., Nitz, T., Nosek, D., Novotny, D., Nozka, V., Nunez, H., Ochilo, L. A., Oikonomou, L., Olinto, F., Palatka, A., Pallotta, M., Papenbreer, J., Parente, P., Parra, G., Paul, A., Pech, T., Pedreira, M., Pekala, F., Pelayo, J., Pena-Rodriguez, R., Pereira, J., Perlin, L. A. S., Perrone, M., Peters, L., Petrera, C., Phuntsok, S., Piegaia, J., Pierog, R., Pieroni, T., Pimenta, P., Pirronello, SILVIA MARIA GRAZIA, Platino, V., Plum, M., Porowski, M., Prado, C., Privitera, R. R., Prouza, P., Quel, M., Querchfeld, E. J., Quinn, S., Ramos-Pollan, S., Rautenberg, R., Ravignani, J., Revenu, D., Ridky, B., Risse, J., Ristori, M., Rizi, P., Rodrigues de Carvalho, Rodriguez, Fern, Ez, G., Rodriguez, Rojo, Rogozin, J., Roncoroni, D., Roth, M. J., Roulet, M., Rovero, E., Ruehl, A. C., Saffi, P., Saftoiu, S. J., Salamida, A., Salazar, F., Saleh, H., Greus, A., Salesa, F., Salina, G., Sanchez, F., Sanchez-Lucas, P., Santos, E. M., Santos, E., Sarazin, F., Sarmento, R., Sarmiento, C. A., Sato, R., Schauer, M., Scherini, V., Schieler, H., Schimp, M., Schmidt, D., Scholten, O., Schovanek, P., Schroeder, F. G., Schulz, A., Schulz, J., Schumacher, J., Sciutto, S. J., Segreto, A., Settimo, M., Shadkam, A., Shellard, R. C., Sigl, G., Silli, G., Sima, O., Smialkowski, A., Smida, R., Snow, G. R., Sommers, P., Sonntag, S., Sorokin, J., Squartini, R., Stanca, D., Stanic, S., Stasielak, J., Stassi, P., Strafella, F., Suarez, F., Suarez, Duran, Sudholz, M., Suomijarvi, T., Supanitsky, T., Swain, A. D., Szadkowski, J., Taboada, Z., Taborda, A., Tapia, O. A., Theodoro, A., Timmermans, V. M., Todero, Peixoto, Tomankova, C. J., Tome, L., Torralba, Elipe, Travnicek, G., Trini, P., Ulrich, M., Unger, R., Urban, M., Valdes, Galicia, Valino, J. F., Valore, I., Van, Aar, Van, Bodegom, van den Berg, A. M., Van, Vliet, BONILLA VARELA, Adelaida, Vargas, Cardenas, Varner, B., Vazquez, G., Vazquez, J. R., Veberic, R. A., Vergara, Quispe, Verzi, I. D., Vicha, V., Villasenor, J., Vorobiov, L., Wahlberg, S., Wainberg, H., Walz, O., Watson, D., Weber, A. A., Weindl, M., Wiencke, A., Wilczynski, L., Winchen, H., Wirtz, T., Wittkowski, M., Wundheiler, D., Yang, B., Yelos, L., Yushkov, D., Zas, A., Zavrtanik, E., Zavrtanik, D., Zepeda, M., Zimmermann, A., Ziolkowski, B., Zong, M., Zong, Z., and Pierre Auger Collaboration

Published
2018

11. Auslegung und Optimierung einer Bestrahlungseinrichtung für die Bor-Neutroneneinfangtherapie an autotransplantierten Organen

Author

Knorr, Jürgen, Baumann, M., Otto, G., Hampel, G., Technische Universität Dresden, Wortmann, Birgit, Knorr, Jürgen, Baumann, M., Otto, G., Hampel, G., Technische Universität Dresden, and Wortmann, Birgit

Abstract

Es besteht ein großer Bedarf an einer Therapie für Krebserkrankungen mit diffusen, nicht operablen Metastasen an vitalen Organen. Bei Metastasenbildung werden die Patienten im Allgemeinen nicht für eine Transplantation mit Spenderorganen vorgesehen. Das bedeutet, bei Nichtansprechen einer Chemotherapie gibt es derzeit keine Therapiealternative für diese Patienten. Wenn eine Transplantation der betroffenen Organe möglich ist, besteht eine Chance für die Anwendung eines neuen therapeutischen Konzeptes. Dieses Konzept basiert auf der Bestrahlung des isolierten Organs (Autotransplantation) mittels der Bor-Neutronen-Einfang-Therapie (BNCT). Das betreffende Organ des Patienten wird dabei zeitweise explantiert und in diesem Zeitraum einer Bestrahlungstherapie unterzogen. Diese Therapieform erfordert kein Spenderorgan und es kann dementsprechend auch zu keinen Abstoßungsreaktionen des Immunsystems durch körperfremdes Gewebe kommen. Erstmalig wurde dieses Verfahren im Dezember 2001 an der Universität Pavia an einem Patienten erfolgreich durchgeführt und damit die prinzipielle Machbarkeit belegt. Bis heute wurde in Pavia noch ein weiterer Patient mit diesem Verfahren behandelt. Nach diesen ersten Heilungsversuchen ist es jetzt erforderlich den therapeutischen Nutzen der Methode reproduzierbar nachzuweisen und diese dann für die Routineanwendung verfügbar zu machen. Das ist eine wesentliche Voraussetzung für die erfolgreiche Einführung dieser Therapieform. Im Rahmen dieser Arbeit soll eine für diese Therapieform optimierte Bestrahlungseinrichtung entwickelt werden. Als Referenzorgan wird die Leber betrachtet, aufgrund ihrer hohen Wahrscheinlichkeit für eine Metastasenbildung, des Mangels an Spenderorganen und fehlender Therapiealternativen. Als geeignete Referenzneutronenquelle bietet sich der TRIGA-Reaktor an. Für diesen Reaktortyp wird die Bestrahlungseinrichtung mit technischen Details und Abmessungen konzipiert.:1. Einleitung 2. Grundlagen 2.1 Krebserkrankungen der Leber 2

Published
2018

12. Comparison of EPR response of pure alanine and alanine with gadolinium dosimeters exposed to TRIGA Mainz reactor

Author

Panzeca, S., Marrale, M., Schmitz, T., Gallo, S., Hampel, G., Longo, A., Tranchina, L., Brai, M., PANZECA, S, MARRALE, M, SCHMITZ, T, GALLO, S, HAMPEL, G, LONGO, A, TRANCHINA, L, and BRAI, M

Subjects
Gadolinium, ESR, EPR, Alanine, FLUKA, Settore ING-IND/18 - Fisica Dei Reattori Nucleari, Settore FIS/01 - Fisica Sperimentale, Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)
Abstract

The development of Neutron Capture Therapy (NCT) for cancer treatments has stimulated the research for beam characterization in order to optimize the therapy procedures. The NCT has found to be promising for treatments of tumours which hardly can be treated with other techniques, such as gliomas. Alongside with the improvements of this technique, the development of procedures for the beam characterization arouses great interest in order to optimize the therapy protocol by reliably determining the various (neutronic and photonic) components of the mixed beam usually employed for therapy. Electron Paramagnetic Resonance (EPR) dosimetry for electron and photon beams with alanine has attracted the attention of many research groups for dosimetric purposes. Furthermore, the applications of EPR dosimetry for high LET radiation beams, such as carbon ions and neutrons, are continuously increasing. This is because of the very good dosimetric features of alanine EPR detectors such as: tissue equivalence for photon beams, linearity of its dose-response over a wide range, high stability of radiation induced free radicals, no destructive read-out procedure, no need of sample treatment before EPR signal measurement and low cost of the dosimeters. Moreover, in order to improve the sensitivity to thermal neutrons of alanine dosimeters the addition of nuclei such as gadolinium oxidewas previously studied. The choice of Gd as additive nucleus is due to its very high capture cross section to thermal neutrons and to the possibility for secondary particles produced after interaction with thermal neutrons of releasing their energy in the neighbourhood of the reaction site. In particular, it was found that low concentration (i.e. 5% by weight) of gadolinium oxide brings about an neutron sensitivity enhancement of more than 10 times without heavily reducing tissue equivalence. We have studied the response of alanine pellets with and without gadolinium exposed to the thermal column of the TRIGA Mark II research reactor at the University of Mainz. Pure alanine dosimeters used were produced by Synergy Health (Germany) whereas the Gd-added dosimeters were produced at the University of Palermo. The irradiations were performed inside polyethylene holders to guarantee charged particles equilibrium conditions. The results of EPR experiments are compared to Monte Carlo (MC) simulations aimed at obtaining information about the contribution of the various components to the total dose measured by means of EPR dosimeters. For alanine dosimeters a good agreement between experimental data and MC simulation have been achieved.

Published
2015

26. Additional results from the first dedicated search for neutron–mirror–neutron oscillations

Author

Bodek, K., Kistryn, S., Kuźniak, M., Zejma, J., Burghoff, M., Knappe-Grüneberg, S., Sander-Thoemmes, T., Schnabel, A., Trahms, L., Ban, G., Lefort, T., Naviliat-Cuncic, O., Khomutov, N., Knowles, Paul E., Pazgalev, Anatoly S., Weis, Antoine, Rogel, G., Quéméner, G., Rebreyend, D., Roccia, S., Bison, Georg, Severijns, N., Eberhardt, K., Hampel, G., Heil, W., Kratz, J.V., Lauer, T., Plonka-Spehr, C., Sobolev, Yu., Wiehl, N., Altarev, I., Fierlinger, P., Gutsmiedl, E., Paul, S., Stoepler, R., Daum, M., Henneck, R., Kirch, K., Knecht, A., Lauss, B., Mtchedlishvili, A., Petzoldt, G., and Zsigmond, G.

Abstract

The existence of a mirror world holding a copy of our ordinary particle spectrum could lead to oscillations between the neutron (n) and its mirror partner (n′). Such oscillations could manifest themselves in storage experiments with ultracold neutrons whose storage lifetime would depend on the applied magnetic field. Here, extended details and measurements from the first dedicated experimental search for nn′ oscillations published in [G. Ban, K. Bodek, M. Daum, R. Henneck, S. Heule, M. Kasprzak, N. Khomutov, K. Kirch, S. Kistryn, A. Knecht, P. Knowles, M. Kuźniak, T. Lefort, A. Mtchedlishvili, O. Naviliat-Cuncic, C. Plonka, G. Quéméner, M. Rebetez, D. Rebreyend, S. Roccia, G. Rogel, M. Tur, A. Weis, J. Zejma, G. Zsigmond, Direct experimental limit on neutron mirror–neutron oscillations, Phys. Rev. Lett. 99 (2007) 161603] will be presented, focussing on a possible dependence of the UCN counts on the magnetic field and its direction. However, at present no significant change in the averaged UCN counts with respect to the applied magnetic field has been found.

Published
2009

27. An Improved Neutron Electric Dipole Moment Experiment

Author

Bodek, K., Kistryn, St, Kuzniak, M., Zejma, J., Burghoff, M., Knappe-Gruneberg, S., Sander-Thoemmes, T., Schnabel, A., Trahms, L., Ban, G., Lefort, T., Naviliat-Cuncic, O., Khomutov, N., Knowles, P., Pazgalev, A. S., Weis, A., Rogel, G., Quemener, G., Rebreyend, D., Roccia, S., Tur, M., Bison, G., Severijns, N., Eberhardt, K., Hampel, G., Heil, W., Kratz, J. V., Lauer, T., Plonka-Spehr, C., Sobolev, Yu, Wiehl, N., Altarev, I., Fierlinger, P., Gutsmiedl, E., Stephan Paul, Stoepler, R., Daum, M., Henneck, R., Kirch, K., Knecht, A., Lauss, B., Mtchedlishvili, A., Petzold, G., Zsigmond, G., Vernay, Emmanuelle, Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Institut Laue-Langevin (ILL), and ILL

Subjects
[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

A new measurement of the neutron EDM, using Ramsey's method of separated oscillatory fields, is in preparation at the new high intensity source of ultra-cold neutrons (UCN) at the Paul Scherrer Institute, Villigen, Switzerland (PSI). The existence of a non-zero nEDM would violate both parity and time reversal symmetry and, given the CPT theorem, might lead to a discovery of new CP violating mechanisms. Already the current upper limit for the nEDM (|d_n, Flavor Physics & CP Violation Conference, Taipei, 2008

Published
2008

28. Towards a new measurement of the neutron electric dipole moment

Author

Altarev, I., Ban, G., Bison, Georg, Bodek, K., Burghoff, M., Cvijovic, Milan, Daum, M., Fierlinger, P., Gutsmiedl, E., Hampel, G., Heil, W., Henneck, R., Horras, M., Khomutov, N., Kirch, K., Kistryn, S., Knappe-Grüneberg, S., Knecht, A., Knowles, Paul E., Kozela, A., Kratz, J. V., Kuchler, F., Kuźniak, M., Lauer, T., Lauss, B., Lefort, T., Mtchedlishvili, A., Naviliat-Cuncic, O., Paul, S., Pazgalev, Anatoly S., Petzoldt, G., Pierre, E., Plonka-Spehr, C., Quéméner, G., Rebreyend, D., Roccia, S., Rogel, G., Sander-Thoemmes, T., Schnabel, A., Severijns, N., Sobolev, Yu., Stoepler, R., Trahms, L., Weis, Antoine, Wiehl, N., Zejma, J., Zsigmond, G., Altarev, I., Ban, G., Bison, Georg, Bodek, K., Burghoff, M., Cvijovic, Milan, Daum, M., Fierlinger, P., Gutsmiedl, E., Hampel, G., Heil, W., Henneck, R., Horras, M., Khomutov, N., Kirch, K., Kistryn, S., Knappe-Grüneberg, S., Knecht, A., Knowles, Paul E., Kozela, A., Kratz, J. V., Kuchler, F., Kuźniak, M., Lauer, T., Lauss, B., Lefort, T., Mtchedlishvili, A., Naviliat-Cuncic, O., Paul, S., Pazgalev, Anatoly S., Petzoldt, G., Pierre, E., Plonka-Spehr, C., Quéméner, G., Rebreyend, D., Roccia, S., Rogel, G., Sander-Thoemmes, T., Schnabel, A., Severijns, N., Sobolev, Yu., Stoepler, R., Trahms, L., Weis, Antoine, Wiehl, N., Zejma, J., and Zsigmond, G.

Abstract

The effort towards a new measurement of the neutron electric dipole moment (nEDM) at the Paul Scherrer Institut's (PSI) new high intensity source of ultracold neutrons (UCN) is described. The experimental technique relies on Ramsey's method of separated oscillatory fields, using UCN in vacuum with the apparatus at ambient temperature. In the first phase, R&D towards the upgrade of the RAL/Sussex/ILL apparatus is being performed at the Institut Laue-Langevin (ILL). In the second phase the apparatus, moved from ILL to PSI, will allow an improvement in experimental sensitivity by a factor of 5. In the third phase, a new spectrometer should gain another order of magnitude in sensitivity. The improvements will be mainly due to (1) much higher UCN intensity, (2) improved magnetometry and magnetic field control, and (3) a double chamber configuration with opposite electric field directions.

Published
2009

29. The new paradigm for wireless network optimization: a synergy of automated processes and human intervention

Author

Hampel, G., primary, Abush-Magder, D., additional, Diaz, A., additional, Drabeck, L.M., additional, Flanagan, M.J., additional, Graybeal, J.M., additional, Hobby, J.D., additional, MacDonald, M., additional, Polakos, P.A., additional, Srinivasan, J., additional, Trickey, H., additional, Zhang, L., additional, and Rittenhouse, G., additional

Published
2005
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31. Experience with cellulose acetate-coated activated charcoal haemoperfusion in the treatment of severe hypnotic drug intoxication.

Author

Crome, P., Hampel, G., Widdop, B., and Goulding, R.

Abstract

A haemoperfusion column containing activated charcoal coated with cellulose acetate was used to treat 7 patients with barbiturate or ethchlorvynol poisoning. Six of the patients showed marked lightening of coma and all showed a significant fall in plasma drug concentration. Plasma drug clearance and platelet loss were similar to those reported for other coated charcoal columns. Cellulose acetate-coated charcoal haemoperfusion may reduce the period of coma in severe poisoning with barbiturates and other hypnotic drugs and thus the morbidity and mortality. [ABSTRACT FROM PUBLISHER]

Published
1980

32. RF power dependence study of large area YBCO thin films.

Author

Zhengxiang Ma, De Obaldia, E., Hampel, G., Polakos, P., Mankiewich, P., Batlogg, B., Prusseit, W., Kinder, H., Anderson, A., Oates, D.E., Ono, R., and Beall, J.

Subjects
SUPERCONDUCTING thin films, PERSONAL communication service systems, MAGNETIC properties of yttrium barium copper oxide, SPUTTERING (Physics), RADIO frequency
Abstract

In an effort to develop HTS superconducting filters with sufficient power handling capability for PCS (Personal Communication Services) base station transmit applications, we have undertaken a study of the power dependence of large area YBCO thin films on LaAlO/sub 3/ substrates. We employed a coplanar-wave-guide (CPW) resonator technique to obtain the changes of loss and inductance versus circulating microwave currents in the films. Data have been collected on uniform large area (2" diameter) films grown by coevaporation and off-axis sputtering techniques under varying deposition conditions. We found correlations between the RF power dependence and other film properties such as penetration depth and crystal structure. The most intrinsic sample, from the coevaporation technique, characterized by the smallest penetration depth, good orthorhombicity and absence of tetragonal phase, shows the least amount of nonlinearity. Such correlations can be used to prescreen films for fabrication and monitor the film production line. However, films from coevaporation and off-axis sputtering show very distinct power dependent behaviors. [ABSTRACT FROM PUBLISHER]

Published
1997
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34. Thrombin and Histamine Stimulate the Phosphorylation of Elongation Factor 2 in Human Umbilical Vein Endothelial Cells

Author

Mackie, K P, Nairn, A C, Hampel, G, Lam, G, and Jaffe, E A

Abstract

The effects of thrombin and histamine on protein phosphorylation in intact cultured human umbilical vein endothelial cells (HUVEC) prelabeled with 32PO4were investigated. Incubation of HUVEC with either thrombin or histamine, agonists known to induce rapid transient increases in intracellular calcium levels in HUVEC, caused a rapid reversible increase in the phosphorylation of a protein with a Mr= 100,000 independent of the presence of extracellular calcium. Immunological and biochemical studies demonstrated that this Mr= 100,000 protein is elongation factor 2 (EF-2), a substrate previously shown to be phosphorylated by calcium/calmodulin-dependent protein kinase III (Nairn, A. C., and Palfrey, H. C. (1987) J. Biol. Chem. 262, 17299–17303). EF-2 is crucial for protein synthesis because it catalyzes the translocation of peptidyl-tRNA on the ribosome. Phosphoamino acid analysis of the EF-2 immunoprecipitated from HUVEC revealed that all of the thrombin-stimulated phosphorylation occurred on threonine. EF-2 was also phosphorylated when HUVEC were treated with the calcium ionophore, ionomycin. Phosphorylation of EF-2 was not increased by treatment with D-Phe-Pro-Arg-chloromethyl ketone thrombin, phorbol dibutyrate, forskolin, or 8-bromo-cGMP. The transient nature of the phosphorylation of EF-2 is consistent with it having a role in mediating some of the transient effects of thrombin and histamine on endothelial cell protein synthesis and functional capabilities.

Published
1989
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35. Correlation between thrombin-induced prostacyclin production and inositol trisphosphate and cytosolic free calcium levels in cultured human endothelial cells.

Author

Jaffe, E A, Grulich, J, Weksler, B B, Hampel, G, and Watanabe, K

Abstract

Cultured human umbilical vein endothelial cells (HUVEC) stimulated with thrombin are known to synthesize prostacyclin at least in part from arachidonate released by phospholipase A2, an enzyme directly activated by calcium. In this study, thrombin stimulation of Quin 2-loaded HUVEC caused rapid and dose-dependent rises in inositol trisphosphate (IP3) and cytosolic free calcium (Ca2+i) levels which preceded a similarly dose-dependent rise in prostacyclin production measured as 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha) by radioimmunoassay (ED50 = 0.6-0.7 units/ml for all three effects). Thrombin induced these effects in the absence of extracellular calcium (EGTA) or in the presence of either 8-bromo-cAMP or the calmodulin inhibitor W7. Thrombin inactivated with either diisopropyl fluorophosphate or D-Phe-Pro-Arg-chloromethyl ketone was inactive. In contrast, Quin 2-loaded cultured bovine aortic endothelial cells failed to respond to thrombin, although stimulation with trypsin elevated IP3 and Ca2+i levels and increased 6-keto-PGF1 alpha production. Restimulation of HUVEC with thrombin or histamine 5 min after an initial stimulation with thrombin (2 units/ml for 5 min) failed to induce a second rise in either IP3 or Ca2+i levels or further production of 6-keto-PGF1 alpha, whereas restimulation with ionomycin in the presence or absence of extracellular calcium elevated Ca2+i levels and induced further 6-keto-PGF1 alpha production. However, if the initial stimulation with thrombin was terminated by addition of D-Phe-Pro-Arg-chloromethyl ketone within 10-60 s, restimulation with a second dose of thrombin induced second rises in both IP3 and Ca2+i levels and additional 6-keto-PGF1 alpha production that were greatest when the initial thrombin stimulus was briefest. These results are consistent with the conclusion that IP3 acts as a second messenger by which thrombin elevates Ca2+i levels and initiates prostacyclin synthesis in HUVEC and that in vivo endothelial cells may be stimulated multiple times to synthesize prostacyclin if each period of stimulation is brief.

Published
1987
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36. Additional results from the first dedicated search for neutron–mirror–neutron oscillations

Author

Bodek, K., Kistryn, S., Kuźniak, M., Zejma, J., Burghoff, M., Knappe-Grüneberg, S., Sander-Thoemmes, T., Schnabel, A., Trahms, L., Ban, G., Lefort, T., Naviliat-Cuncic, O., Khomutov, N., Knowles, Paul E., Pazgalev, Anatoly S., Weis, Antoine, Rogel, G., Quéméner, G., Rebreyend, D., Roccia, S., Bison, Georg, Severijns, N., Eberhardt, K., Hampel, G., Heil, W., Kratz, J.V., Lauer, T., Plonka-Spehr, C., Sobolev, Yu., Wiehl, N., Altarev, I., Fierlinger, P., Gutsmiedl, E., Paul, S., Stoepler, R., Daum, M., Henneck, R., Kirch, K., Knecht, A., Lauss, B., Mtchedlishvili, A., Petzoldt, G., Zsigmond, G., Bodek, K., Kistryn, S., Kuźniak, M., Zejma, J., Burghoff, M., Knappe-Grüneberg, S., Sander-Thoemmes, T., Schnabel, A., Trahms, L., Ban, G., Lefort, T., Naviliat-Cuncic, O., Khomutov, N., Knowles, Paul E., Pazgalev, Anatoly S., Weis, Antoine, Rogel, G., Quéméner, G., Rebreyend, D., Roccia, S., Bison, Georg, Severijns, N., Eberhardt, K., Hampel, G., Heil, W., Kratz, J.V., Lauer, T., Plonka-Spehr, C., Sobolev, Yu., Wiehl, N., Altarev, I., Fierlinger, P., Gutsmiedl, E., Paul, S., Stoepler, R., Daum, M., Henneck, R., Kirch, K., Knecht, A., Lauss, B., Mtchedlishvili, A., Petzoldt, G., and Zsigmond, G.

Abstract

The existence of a mirror world holding a copy of our ordinary particle spectrum could lead to oscillations between the neutron (n) and its mirror partner (n′). Such oscillations could manifest themselves in storage experiments with ultracold neutrons whose storage lifetime would depend on the applied magnetic field. Here, extended details and measurements from the first dedicated experimental search for nn′ oscillations published in [G. Ban, K. Bodek, M. Daum, R. Henneck, S. Heule, M. Kasprzak, N. Khomutov, K. Kirch, S. Kistryn, A. Knecht, P. Knowles, M. Kuźniak, T. Lefort, A. Mtchedlishvili, O. Naviliat-Cuncic, C. Plonka, G. Quéméner, M. Rebetez, D. Rebreyend, S. Roccia, G. Rogel, M. Tur, A. Weis, J. Zejma, G. Zsigmond, Direct experimental limit on neutron mirror–neutron oscillations, Phys. Rev. Lett. 99 (2007) 161603] will be presented, focussing on a possible dependence of the UCN counts on the magnetic field and its direction. However, at present no significant change in the averaged UCN counts with respect to the applied magnetic field has been found.

37. Neutron velocity distribution from a superthermal solid 2H2 ultracold neutron source

Author

Altarev, I., Daum, M., Frei, A., Gutsmiedl, E., Hampel, G., Hartmann, F., Heil, W., Knecht, A., Kratz, J., Lauer, T., Meier, M., Paul, S., Schmidt, U., Sobolev, Y., Wiehl, N., Zsigmond, G., Altarev, I., Daum, M., Frei, A., Gutsmiedl, E., Hampel, G., Hartmann, F., Heil, W., Knecht, A., Kratz, J., Lauer, T., Meier, M., Paul, S., Schmidt, U., Sobolev, Y., Wiehl, N., and Zsigmond, G.

Abstract

We have determined for the first time the velocity distribution of neutrons from a solid 2H2 ultracold neutron (UCN) source. The spectrum rises sharply above 4.5m/s and has a maximum around 7m/s after transport in an 8m long guide. The number of neutrons in the UCN velocity range (< 7m/s) may be increased by a factor of two by placing the experiment 1m above the UCN source level

38. Towards a new measurement of the neutron electric dipole moment

Author

Altarev, I., Ban, G., Bison, Georg, Bodek, K., Burghoff, M., Cvijovic, Milan, Daum, M., Fierlinger, P., Gutsmiedl, E., Hampel, G., Heil, W., Henneck, R., Horras, M., Khomutov, N., Kirch, K., Kistryn, S., Knappe-Grüneberg, S., Knecht, A., Knowles, Paul E., Kozela, A., Kratz, J. V., Kuchler, F., Kuźniak, M., Lauer, T., Lauss, B., Lefort, T., Mtchedlishvili, A., Naviliat-Cuncic, O., Paul, S., Pazgalev, Anatoly S., Petzoldt, G., Pierre, E., Plonka-Spehr, C., Quéméner, G., Rebreyend, D., Roccia, S., Rogel, G., Sander-Thoemmes, T., Schnabel, A., Severijns, N., Sobolev, Yu., Stoepler, R., Trahms, L., Weis, Antoine, Wiehl, N., Zejma, J., Zsigmond, G., Altarev, I., Ban, G., Bison, Georg, Bodek, K., Burghoff, M., Cvijovic, Milan, Daum, M., Fierlinger, P., Gutsmiedl, E., Hampel, G., Heil, W., Henneck, R., Horras, M., Khomutov, N., Kirch, K., Kistryn, S., Knappe-Grüneberg, S., Knecht, A., Knowles, Paul E., Kozela, A., Kratz, J. V., Kuchler, F., Kuźniak, M., Lauer, T., Lauss, B., Lefort, T., Mtchedlishvili, A., Naviliat-Cuncic, O., Paul, S., Pazgalev, Anatoly S., Petzoldt, G., Pierre, E., Plonka-Spehr, C., Quéméner, G., Rebreyend, D., Roccia, S., Rogel, G., Sander-Thoemmes, T., Schnabel, A., Severijns, N., Sobolev, Yu., Stoepler, R., Trahms, L., Weis, Antoine, Wiehl, N., Zejma, J., and Zsigmond, G.

Abstract

The effort towards a new measurement of the neutron electric dipole moment (nEDM) at the Paul Scherrer Institut's (PSI) new high intensity source of ultracold neutrons (UCN) is described. The experimental technique relies on Ramsey's method of separated oscillatory fields, using UCN in vacuum with the apparatus at ambient temperature. In the first phase, R&D towards the upgrade of the RAL/Sussex/ILL apparatus is being performed at the Institut Laue-Langevin (ILL). In the second phase the apparatus, moved from ILL to PSI, will allow an improvement in experimental sensitivity by a factor of 5. In the third phase, a new spectrometer should gain another order of magnitude in sensitivity. The improvements will be mainly due to (1) much higher UCN intensity, (2) improved magnetometry and magnetic field control, and (3) a double chamber configuration with opposite electric field directions.

39. Auslegung und Optimierung einer Bestrahlungseinrichtung für die Bor-Neutroneneinfangtherapie an autotransplantierten Organen

Author

Wortmann, Birgit, Knorr, Jürgen, Baumann, M., Otto, G., Hampel, G., and Technische Universität Dresden

Subjects
ddc:621.3, ddc:620, Bestrahlungseinrichtung, BNCT, autotransplantiert, Leber, ATTLA, MCNP, irradiation, facility, BNCT, autotransplanted, liver, ATTLA, MCNP
Abstract

Es besteht ein großer Bedarf an einer Therapie für Krebserkrankungen mit diffusen, nicht operablen Metastasen an vitalen Organen. Bei Metastasenbildung werden die Patienten im Allgemeinen nicht für eine Transplantation mit Spenderorganen vorgesehen. Das bedeutet, bei Nichtansprechen einer Chemotherapie gibt es derzeit keine Therapiealternative für diese Patienten. Wenn eine Transplantation der betroffenen Organe möglich ist, besteht eine Chance für die Anwendung eines neuen therapeutischen Konzeptes. Dieses Konzept basiert auf der Bestrahlung des isolierten Organs (Autotransplantation) mittels der Bor-Neutronen-Einfang-Therapie (BNCT). Das betreffende Organ des Patienten wird dabei zeitweise explantiert und in diesem Zeitraum einer Bestrahlungstherapie unterzogen. Diese Therapieform erfordert kein Spenderorgan und es kann dementsprechend auch zu keinen Abstoßungsreaktionen des Immunsystems durch körperfremdes Gewebe kommen. Erstmalig wurde dieses Verfahren im Dezember 2001 an der Universität Pavia an einem Patienten erfolgreich durchgeführt und damit die prinzipielle Machbarkeit belegt. Bis heute wurde in Pavia noch ein weiterer Patient mit diesem Verfahren behandelt. Nach diesen ersten Heilungsversuchen ist es jetzt erforderlich den therapeutischen Nutzen der Methode reproduzierbar nachzuweisen und diese dann für die Routineanwendung verfügbar zu machen. Das ist eine wesentliche Voraussetzung für die erfolgreiche Einführung dieser Therapieform. Im Rahmen dieser Arbeit soll eine für diese Therapieform optimierte Bestrahlungseinrichtung entwickelt werden. Als Referenzorgan wird die Leber betrachtet, aufgrund ihrer hohen Wahrscheinlichkeit für eine Metastasenbildung, des Mangels an Spenderorganen und fehlender Therapiealternativen. Als geeignete Referenzneutronenquelle bietet sich der TRIGA-Reaktor an. Für diesen Reaktortyp wird die Bestrahlungseinrichtung mit technischen Details und Abmessungen konzipiert.:1. Einleitung 2. Grundlagen 2.1 Krebserkrankungen der Leber 2.2 Makroskopischer und mikroskopischer Aufbau der Leber 2.3 Beschreibung der Therapieform BNCT 2.4 Biologische Wirkung der Bestrahlung 2.5 Dosiswirkungsbeziehungen 2.6 Kinetik des B-10-Pharmakons 2.7 TRIGA-Reaktor als Referenzneutronenquelle 2.8 Vorgehen beim Aufbau einer Strahlentherapie 2.9 Vorgehen für die Auslegung und Optimierung der spezifischen Bestrahlungseinrichtung am TRIGA-Reaktor in Mainz 2.10 Ausblick 3. Dosimetrie 3.1 Strahlungsfeldgrößen und Dosisbegriff 3.2 Wechselwirkungen der Strahlung mit Materie 3.2.1. Wechselwirkung von Neutronen mit Materie 3.2.2. Wechselwirkung von Photonen mit Materie 3.2.3. Wechselwirkung von Protonen, alpha-Teilchen und Elektronen mit Materie 3.3 Berechnung des Strahlentransportes und der Strahlungsfeldgrößen 3.4 Berechnung der Dosis aus den Strahlungsfeldgrößen 3.5 Berechnung der gewichteten Gesamtdosis und der Dosisanteile der BNCT 4. Anforderungen an die Bestrahlungseinrichtung 4.1 Anforderungen der Therapieform 4.2 Anforderungen aus medizinischer Sicht 4.3 Anforderungen des Medizinproduktegesetzes (MPG) und der zugehörigen Richtlinie 93/42/EWG 4.4 Anforderungen der Referenz-Neutronenquelle 4.4.1 Atomgesetz (AtG) und Verordnungen 4.4.2 Strahlenschutzverordnung (StrlSchV) 5. Programme 5.1 MCNP 5.2 ATTILA 5.3 SCALE 6. Basisdaten für die Berechnungen 6.1 Leber 6.2 TRIGA Mark II Reaktor in Mainz 6.2.1 Aufbau 6.2.2 Abmessungen 6.2.3 Materialien 6.2.4 Leistungshistorie 6.2.5 Energiespektrum und Stärke der Quelle 6.2.6 Vereinfachungen und Randbedingungen 6.3 Wirkungsquerschnitte 7. Rechenmodelle 7.1 Modell zur Bestimmung optimaler Parameter für die Therapieform 7.2 Modelle des TRIGA Mark II Reaktors in Mainz 7.2.1 Modell zur Bestimmung der Quellverteilung 7.2.2 Modell zur Strahlcharakterisierung 7.2.3 Modell für die Bestimmung der Dosisanteile für das autotransplantierte Organ 8. Ergebnisse der Berechnungen 8.1 Darstellung der Ergebnisse 8.2 Optimale Parameter für die geplante Therapieform 8.2.1 Energieverteilung der Quelle 8.2.2 Ausdehnung, Intensitäts- und Winkelverteilung der Quelle 8.2.3 Positionierung des Organs im Strahlenfeld 8.2.4 Bor-Konzentration und Bor-Konzentrationsverhältnis 8.2.5 Zusammenfassung 8.3 Auslegung und Optimierung der Bestrahlungseinrichtung am TRIGA-Mark II Reaktor in Mainz 8.3.1 Charakteristik der Quelle 8.3.2 Festlegung der Position der Bestrahlungseinrichtung 8.3.3 Vergleich der Berechnungen mit Messungen 8.3.4 Optimierung der konstruktiven Ausführung 8.3.4.1 Kollimator 8.3.4.2 Absorber 8.3.4.3 Konverter 8.3.4.4 Filter 8.3.4.5 Abstand der Bestrahlungsposition von der Reaktorkernmitte 8.3.4.6 Zusammenfassung der optimierten konstruktiven Ausführung der Bestrahlungseinrichtung 8.3.5 Dosierungsfehler 8.3.5.1 Diskretisierungsfehler 8.3.5.2 Einfluss der Reaktorfahrweise 8.3.5.3 Einfluss der Aktivierung der Strukturmaterialien 8.4 Wärmebilanz 9. Optimierte Bestrahlungseinrichtung und Maßnahmen für den Umbau 10. Ablaufplan für die Therapie 11. Zielerreichung 12. Zusammenfassung 13. Literaturverzeichnis ANHANG

Published
2007

40. Quantitative bioimaging of p-boronophenylalanine in thin liver tissue sections as a tool for treatment planning in boron neutron capture therapy.

Author

Reifschneider O, Schütz CL, Brochhausen C, Hampel G, Ross T, Sperling M, and Karst U

Subjects
Boron Neutron Capture Therapy, Fructose chemistry, Humans, Liver radiation effects, Liver Neoplasms chemistry, Molecular Imaging, Boron chemistry, Boron Compounds chemistry, Fructose analogs & derivatives, Isotopes chemistry, Liver chemistry, Liver Neoplasms radiotherapy, Radiopharmaceuticals chemistry
Abstract

An analytical method using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was developed and applied to assess enrichment of 10B-containing p-boronophenylalanine-fructose (BPA-f) and its pharmacokinetic distribution in human tissues after application for boron neutron capture therapy (BNCT). High spatial resolution (50 μm) and limits of detection in the low parts-per-billion range were achieved using a Nd:YAG laser of 213 nm wavelength. External calibration by means of 10B-enriched standards based on whole blood proved to yield precise quantification results. Using this calibration method, quantification of 10B in cancerous and healthy tissue was carried out. Additionally, the distribution of 11B was investigated, providing 10B enrichment in the investigated tissues. Quantitative imaging of 10B by means of LA-ICP-MS was demonstrated as a new option to characterise the efficacy of boron compounds for BNCT.

Published
2015
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41. Cellular uptake and in vitro antitumor efficacy of composite liposomes for neutron capture therapy.

Author

Peters T, Grunewald C, Blaickner M, Ziegner M, Schütz C, Iffland D, Hampel G, Nawroth T, and Langguth P

Subjects
Brain Neoplasms pathology, Contrast Media pharmacokinetics, Gadolinium DTPA pharmacokinetics, Glioma pathology, Humans, In Vitro Techniques, Magnetic Resonance Imaging methods, Monte Carlo Method, Tumor Cells, Cultured, Brain Neoplasms radiotherapy, Cell Proliferation radiation effects, Glioma radiotherapy, Liposomes, Neutron Capture Therapy, Neutrons
Abstract

Background: Neutron capture therapy for glioblastoma has focused mainly on the use of (10)B as neutron capture isotope. However, (157)Gd offers several advantages over boron, such as higher cross section for thermal neutrons and the possibility to perform magnetic resonance imaging during neutron irradiation, thereby combining therapy and diagnostics. We have developed different liposomal formulations of gadolinium-DTPA (Magnevist®) for application in neutron capture therapy of glioblastoma. The formulations were characterized physicochemically and tested in vitro in a glioma cell model for their effectiveness., Methods: Liposomes entrapping gadolinium-DTPA as neutron capture agent were manufactured via lipid/film-extrusion method and characterized with regard to size, entrapment efficiency and in vitro release. For neutron irradiation, F98 and LN229 glioma cells were incubated with the newly developed liposomes and subsequently irradiated at the thermal column of the TRIGA reactor in Mainz. The dose rate derived from neutron irradiation with (157)Gd as neutron capturing agent was calculated via Monte Carlo simulations and set in relation to the respective cell survival., Results: The liposomal Gd-DTPA reduced cell survival of F98 and LN229 cells significantly. Differences in liposomal composition of the formulations led to distinctly different outcome in cell survival. The amount of cellular Gd was not at all times proportional to cell survival, indicating that intracellular deposition of formulated Gd has a major influence on cell survival. The majority of the dose contribution arises from photon cross irradiation compared to a very small Gd-related dose., Conclusions: Liposomal gadolinium formulations represent a promising approach for neutron capture therapy of glioblastoma cells. The liposome composition determines the uptake and the survival of cells following radiation, presumably due to different uptake pathways of liposomes and intracellular deposition of gadolinium-DTPA. Due to the small range of the Auger and conversion electrons produced in (157)Gd capture, the proximity of Gd-atoms to cellular DNA is a crucial factor for infliction of lethal damage. Furthermore, Gd-containing liposomes may be used as MRI contrast agents for diagnostic purposes and surveillance of tumor targeting, thus enabling a theranostic approach for tumor therapy.

Published
2015
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42. Value of emergency toxicological investigations in differential diagnosis of coma.

Author

Helliwell M, Hampel G, Sinclair E, Huggett A, and Flanagan RJ

Subjects
Acute Disease, Adolescent, Adult, Aged, Cerebral Hemorrhage complications, Cerebral Hemorrhage diagnosis, Child, Child, Preschool, Coma chemically induced, Coma etiology, Diagnosis, Differential, Female, Humans, Male, Middle Aged, Pharmaceutical Preparations analysis, Poisoning metabolism, Respiration, Artificial, Coma diagnosis, Emergencies, Poisoning diagnosis
Abstract

Out of 208 cases of coma of unknown aetiology referred to the poisons unit of this hospital during 1978 for emergency toxicological investigations, 108 were found to be due to self-poisoning medical conditions, mainly neurological, accounted for coma in 90 patients; the cause was not ascertained in the remaining 10 cases. More than one preparation had been ingested by 58 (54%) of the poisoned patients, although barbiturates were the drugs most commonly encountered in the severe cases. Toxicological investigations should be considered in the differential diagnosis of coma when history, physical examination, and emergency biochemical measurements yield little diagnostic information.

Published
1979
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