Circular tour of the centre of Höchst Frankfurt am Main

CIRCULAR TOUR OF THE CENTRE OF HÖCHST FRANKFURT AM MAIN Circular tour of the centre of Höchst Frankfurt am Main / Lederer, Anne (Rights reserved) ( -

Additive Dose Response Models: Explicit Formulation and the Loewe Additivity Consistency Condition

Lederer S, M. H. Dijkstra T, Heskes T. Additive Dose Response Models: Explicit Formulation and the Loewe Additivity Consistency Condition. Frontiers in Pharmacology. 2018;9: 31

Measurement of the N 14 (n,p) C 14 cross section at the CERN n_TOF facility from subthermal energy to 800 keV

Background: The 14N(n,p)14C reaction is of interest in neutron capture therapy, where nitrogen-related dose is the main component due to low-energy neutrons, and in astrophysics, where 14N acts as a neutron poison in the s process. Several discrepancies remain between the existing data obtained in partial energy ranges: thermal energy, keV region, and resonance region. Purpose: We aim to measure the 14N(n,p)14C cross section from thermal to the resonance region in a single measurement for the first time, including characterization of the first resonances, and provide calculations of Maxwellian averaged cross sections (MACS). Method: We apply the time-of-flight technique at Experimental Area 2 (EAR-2) of the neutron time-of-flight (n_TOF) facility at CERN. 10B(n,a)7Li and 235U(n,f) reactions are used as references. Two detection systems are run simultaneously, one on beam and another off beam. Resonances are described with the R-matrix code sammy. Results: The cross section was measured from subthermal energy to 800 keV, resolving the first two resonances (at 492.7 and 644 keV). A thermal cross section was obtained (1.809±0.045 b) that is lower than the two most recent measurements by slightly more than one standard deviation, but in line with the ENDF/B-VIII.0 and JEFF-3.3 evaluations. A 1/v energy dependence of the cross section was confirmed up to tens of keV neutron energy. The low energy tail of the first resonance at 492.7 keV is lower than suggested by evaluated values, while the overall resonance strength agrees with evaluations. Conclusions: Our measurement has allowed determination of the 14N(n,p) cross section over a wide energy range for the first time. We have obtained cross sections with high accuracy (2.5%) from subthermal energy to 800 keV and used these data to calculate the MACS for kT=5 to kT=100 keV.We thank Mr. Wilhelmus Vollenberg for the preparation of the adenine samples. This work was partially supported by Spanish Ministerio de Ciencia e Innovación (PID2020- 117969RB-I00), Junta de Andalucía (FEDER Andalucia 2014-2020) Projects No. P20-00665 and No. B-FQM-156- UGR20. This work was also supported by the UK Science and Facilities Council (ST/M006085/1, ST/P004008/1), by the European Research Council ERC-2015-StG No. 677497, and by the funding agencies of the n_TOF participating in- stitutes. P.T. acknowledges support from the Spanish Ministry of Science, Innovation and Universities under the FPU Grant No. FPU17/02305.Article signat per 132 autors/es: Pablo Torres-Sánchez, Javier Praena, Ignacio Porras, Marta Sabaté-Gilarte, Claudia Lederer-Woods, Oliver Aberle, Victor Alcayne, Simone Amaducci, Józef Andrzejewski, Laurent Audouin, Vicente Bécares, Victor Babiano-Suarez, Michael Bacak, Massimo Barbagallo, František Beˇcváˇr, Giorgio Bellia, Eric Berthoumieux, Jon Billowes, Damir Bosnar, Adam Brown, Maurizio Busso, Manuel Caamaño, Luis Caballero, Francisco Calviño, Marco Calviani, Daniel Cano-Ott, Adria Casanovas, Francesco Cerutti, Yonghao Chen, Enrico Chiaveri, Nicola Colonna, Guillem Cortés, Miguel Cortés-Giraldo, Luigi Cosentino, Sergio Cristallo, Lucia-Anna Damone, Maria Diakaki, Mirco Dietz, César Domingo-Pardo, Rugard Dressler, Emmeric Dupont, Ignacio Durán, Zinovia Eleme, Beatriz Fernández-Domínguez, Alfredo Ferrari, Francisco Javier Ferrer, Paolo Finocchiaro, Valter Furman, Kathrin Göbel, Ruchi Garg, Aleksandra Gawlik-Ramiega, Benoit Geslot, Simone Gilardoni, Tudor Glodariu, Isabel Gonçalves, Enrique González-Romero, Carlos Guerrero, Frank Gunsing, Hideo Harada, Stephan Heinitz, Jan Heyse, David Jenkins, Erwin Jericha, Franz Käppeler, Yacine Kadi, Atsushi Kimura, Niko Kivel, Michael Kokkoris, Yury Kopatch, Milan Krtiˇcka, Deniz Kurtulgil, Ion Ladarescu, Helmut Leeb, Jorge Lerendegui-Marco, Sergio Lo Meo, Sarah-Jane Lonsdale, Daniela Macina, Alice Manna, Trinitario Martínez, Alessandro Masi, Cristian Massimi, Pierfrancesco Mastinu, Mario Mastromarco, Francesca Matteucci, Emilio-Andrea Maugeri, Annamaria Mazzone, Emilio Mendoza, Alberto Mengoni, Veatriki Michalopoulou, Paolo Maria Milazzo, Federica Mingrone, Agatino Musumarra, Alexandru Negret, Ralf Nolte, Francisco Ogállar, Andreea Oprea, Nikolas Patronis, Andreas Pavlik, Jarosław Perkowski, Luciano Persanti, José-Manuel Quesada, Désirée Radeck, Diego Ramos-Doval, Thomas Rauscher, René Reifarth, Dimitri Rochman, Carlo Rubbia, Alok Saxena, Peter Schillebeeckx, Dorothea Schumann, Gavin Smith, Nikolay Sosnin, Athanasios Stamatopoulos, Giuseppe Tagliente, José Tain, Zeynep Talip, Ariel Tarifeño-Saldivia, Laurent Tassan-Got, Andrea Tsinganis, Jiri Ulrich, Sebastian Urlass, Stanislav Valenta, Gianni Vannini, Vincenzo Variale, Pedro Vaz, Alberto Ventura, Vasilis Vlachoudis, Rosa Vlastou, Anton Wallner, PhilipJohn Woods, Tobias Wright, and Petar Žugec.Postprint (published version

Benefits from using mixed precision computations in the ELPA-AEO and ESSEX-II eigensolver projects

We first briefly report on the status and recent achievements of the ELPA-AEO (Eigenvalue Solvers for Petaflop Applications - Algorithmic Extensions and Optimizations) and ESSEX II (Equipping Sparse Solvers for Exascale) projects. In both collaboratory efforts, scientists from the application areas, mathematicians, and computer scientists work together to develop and make available efficient highly parallel methods for the solution of eigenvalue problems. Then we focus on a topic addressed in both projects, the use of mixed precision computations to enhance efficiency. We give a more detailed description of our approaches for benefiting from either lower or higher precision in three selected contexts and of the results thus obtained

First Results of the 140^{140}Ce(n,γ)141^{141}Ce Cross-Section Measurement at n_TOF

An accurate measurement of the $^{140}$Ce(n,γ) energy-dependent cross-section was performed at the n_TOF facility at CERN. This cross-section is of great importance because it represents a bottleneck for the s-process nucleosynthesis and determines to a large extent the cerium abundance in stars. The measurement was motivated by the significant difference between the cerium abundance measured in globular clusters and the value predicted by theoretical stellar models. This discrepancy can be ascribed to an overestimation of the $^{140}$Ce capture cross-section due to a lack of accurate nuclear data. For this measurement, we used a sample of cerium oxide enriched in $^{140}$Ce to 99.4%. The experimental apparatus consisted of four deuterated benzene liquid scintillator detectors, which allowed us to overcome the difficulties present in the previous measurements, thanks to their very low neutron sensitivity. The accurate analysis of the p-wave resonances and the calculation of their average parameters are fundamental to improve the evaluation of the $^{140}$Ce Maxwellian-averaged cross-section

First results of the140ce(N,ү)141ce cross-section measurement at n_tof

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)An accurate measurement of the140Ce(n,ү) energy-dependent cross-section was performed at the n_TOF facility at CERN. This cross-section is of great importance because it represents a bottleneck for the s-process nucleosynthesis and determines to a large extent the cerium abundance in stars. The measurement was motivated by the significant difference between the cerium abundance measured in globular clusters and the value predicted by theoretical stellar models. This discrepancy can be ascribed to an overestimation of the140Ce capture cross-section due to a lack of accurate nuclear data. For this measurement, we used a sample of cerium oxide enriched in140Ce to 99.4%. The experimental apparatus consisted of four deuterated benzene liquid scintillator detectors, which allowed us to overcome the difficulties present in the previous measurements, thanks to their very low neutron sensitivity. The accurate analysis of the p-wave resonances and the calculation of their average parameters are fundamental to improve the evaluation of the140Ce Maxwellian-averaged cross-section.Peer reviewe

First Results of the 140^{140}Ce(n,γ)141^{141}Ce Cross-Section Measurement at n_TOF

An accurate measurement of the $^{140}$Ce(n,γ) energy-dependent cross-section was performed at the n_TOF facility at CERN. This cross-section is of great importance because it represents a bottleneck for the s-process nucleosynthesis and determines to a large extent the cerium abundance in stars. The measurement was motivated by the significant difference between the cerium abundance measured in globular clusters and the value predicted by theoretical stellar models. This discrepancy can be ascribed to an overestimation of the $^{140}$Ce capture cross-section due to a lack of accurate nuclear data. For this measurement, we used a sample of cerium oxide enriched in $^{140}$Ce to 99.4%. The experimental apparatus consisted of four deuterated benzene liquid scintillator detectors, which allowed us to overcome the difficulties present in the previous measurements, thanks to their very low neutron sensitivity. The accurate analysis of the p-wave resonances and the calculation of their average parameters are fundamental to improve the evaluation of the $^{140}$Ce Maxwellian-averaged cross-section

Study of the photon strength functions and level density in the gamma decay of the n+U-234 reaction

The accurate calculations of neutron-induced reaction cross sections are relevant for many nuclear applications. The photon strength functions and nuclear level densities are essential inputs for such calculations. These quantities for U-235 are studied using the measurement of the gamma de-excitation cascades in radiative capture on U-234 with the Total Absorption Calorimeter at n_TOF at CERN. This segmented 4 pi gamma calorimeter is designed to detect gamma rays emitted from the nucleus with high efficiency. This experiment provides information on gamma multiplicity and gamma spectra that can be compared with numerical simulations. The code DICEBOXC is used to simulate the gamma cascades while GEANT4 is used for the simulation of the interaction of these gammas with the TAC materials. Available models and their parameters are being tested using the present data. Some preliminary results of this ongoing study are presented and discussed

Measurement and analysis of the 246Cm and 248Cm neutron capture cross-sections at the EAR2 of the n_TOF facility at CERN

The 246Cm(n,γ) and 248Cm(n,γ) cross-sections have been measured at the Experimental Area 2 (EAR2) of the n_TOF facility at CERN with three C6D6 detectors. This measurement is part of a collective effort to improve the capture cross-section data for Minor Actinides (MAs), which are required to estimate the production and transmutation rates of these isotopes in light water reactors and innovative reactor systems. In particular, the neutron capture in 246Cm and 248Cm open the path for the formation of other Cm isotopes and heavier elements such as Bk and Cf and the knowledge of (n,γ) cross-sections of these Cm isotopes plays an important role in the transport, transmutation and storage of the spent nuclear fuel. The reactions 246Cm(n,γ) and 248Cm(n,γ) have been the two first capture measurements analyzed at n_TOF EAR2. Until this experiment and two recent measurements performed at J-PARC, there was only one set of data of the capture cross-sections of 246Cm and 248Cm, that was obtained in 1969 in an underground nuclear explosion experiment. In the measurement at n_TOF a total of 13 resonances of 246Cm between 4 and 400 eV and 5 of 248Cm between 7 and 100 eV have been identified and fitted. The radiative kernels obtained for 246Cm are compatible with JENDL-5, but some of them are not with JENDL-4, which has been adopted by JEFF-3.3 and ENDF/B-VIII.0. The radiative kernels obtained for the first three 248Cm resonances are compatible with JENDL-5, however, the other two are not compatible with any other evaluation and are 20 and 60% larger than JENDL-5

International Impact of COVID-19 on the Diagnosis of Heart Disease

BACKGROUND The coronavirus disease 2019 (COVID-19) pandemic has adversely affected diagnosis and treatment of noncommunicable diseases. Its effects on delivery of diagnostic care for cardiovascular disease, which remains the leading cause of death worldwide, have not been quantified.OBJECTIVES The study sought to assess COVID-19`s impact on global cardiovascular diagnostic procedural volumes and safety practices.METHODS The International Atomic Energy Agency conducted a worldwide survey assessing alterations in cardiovascular procedure volumes and safety practices resulting from COVID-19. Noninvasive and invasive cardiac testing volumes were obtained from participating sites for March and April 2020 and compared with those from March 2019. Availability of personal protective equipment and pandemic-related testing practice changes were ascertained.RESULTS Surveys were submitted from 909 inpatient and outpatient centers performing cardiac diagnostic procedures, in 108 countries. Procedure volumes decreased 42% from March 2019 to March 2020, and 64% from March 2019 to April 2020. Transthoradc echocardiography decreased by 59%, transesophageat echocardiography 76%, and stress tests 78%, which varied between stress modalities. Coronary angiography (invasive or computed tomography) decreased 55% (p < 0.001 for each procedure). hi multivariable regression, significantly greater reduction in procedures occurred for centers in countries with lower gross domestic product. Location in a low-income and lower-middle-income country was associated with an additional 22% reduction in cardiac procedures and less availability of personal protective equipment and teteheatth.CONCLUSIONS COVID-19 was associated with a significant and abrupt reduction in cardiovascular diagnostic testing across the globe, especially affecting the world's economically challenged. Further study of cardiovascular outcomes and COVID-19-related changes in care delivery is warranted. (C) 2021 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation