93 results on '"Thorsten Weber"'
Search Results
2. Electron Scattering from 1-Methyl-5-Nitroimidazole: Cross-Sections for Modeling Electron Transport through Potential Radiosensitizers
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Ana I. Lozano, Lidia Álvarez, Adrián García-Abenza, Carlos Guerra, Fábris Kossoski, Jaime Rosado, Francisco Blanco, Juan Carlos Oller, Mahmudul Hasan, Martin Centurion, Thorsten Weber, Daniel S. Slaughter, Deepthy M. Mootheril, Alexander Dorn, Sarvesh Kumar, Paulo Limão-Vieira, Rafael Colmenares, and Gustavo García
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electron scattering cross-sections ,electron impact molecular fragmentation ,molecular radiosensitizers ,radiation damage ,ionization ,dissociation ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
In this study, we present a complete set of electron scattering cross-sections from 1-Methyl-5-Nitroimidazole (1M5NI) molecules for impact energies ranging from 0.1 to 1000 eV. This information is relevant to evaluate the potential role of 1M5NI as a molecular radiosensitizers. The total electron scattering cross-sections (TCS) that we previously measured with a magnetically confined electron transmission apparatus were considered as the reference values for the present analysis. Elastic scattering cross-sections were calculated by means of two different schemes: The Schwinger multichannel (SMC) method for the lower energies (below 15 eV) and the independent atom model-based screening-corrected additivity rule with interferences (IAM-SCARI) for higher energies (above 15 eV). The latter was also applied to calculate the total ionization cross-sections, which were complemented with experimental values of the induced cationic fragmentation by electron impact. Double differential ionization cross-sections were measured with a reaction microscope multi-particle coincidence spectrometer. Using a momentum imaging spectrometer, direct measurements of the anion fragment yields and kinetic energies by the dissociative electron attachment are also presented. Cross-sections for the other inelastic channels were derived with a self-consistent procedure by sampling their values at a given energy to ensure that the sum of the cross-sections of all the scattering processes available at that energy coincides with the corresponding TCS. This cross-section data set is ready to be used for modelling electron-induced radiation damage at the molecular level to biologically relevant media containing 1M5NI as a potential radiosensitizer. Nonetheless, a proper evaluation of its radiosensitizing effects would require further radiobiological experiments.
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- 2023
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3. Blockchain-Based Reference Architecture for Automated, Transparent, and Notarized Attestation of Compliance Adaptations
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Thorsten Weber and Rüdiger Buchkremer
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cloud computing ,software ,configuration ,compliance ,blockchain ,smart contracts ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
With cloud computing, organizations must comply with applicable laws, policies, and best practices. Companies typically rely on cloud service providers to implement and adopt regulations. This consulting phase is often time-consuming, costly, and not transparent. Organizations must trust the third party’s implementation and associated documentation processes. To resolve this dilemma, we present a blockchain-based reference architecture for the automated, transparent, and notarized attestation of such compliance adaptations. Before proposing a solution, our approach is to understand the underlying research context. We conduct a machine-learning-supported systematic literature review to create a knowledge base. A reference architecture, including a prototype for configuring intrusion-detection systems, is developed using design science research. A mixed-methods-based approach is used for the evaluation of the proposed architecture. A quantitative survey is then used to show that the user experience of the developed prototype can be rated as positive, with an average value of 0.7. Finally, two focus group discussions are used to analyze the presented prototype qualitatively. As a result, we demonstrate how to actively support secure and trustworthy communication between a cloud service provider and an organization applying blockchain configurations.
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- 2022
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4. Investigating resonant low-energy electron attachment to formamide: Dynamics of model peptide bond dissociation and other fragmentation channels
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Guglielmo Panelli, Ali Moradmand, Brandon Griffin, Kyle Swanson, Thorsten Weber, Thomas N. Rescigno, C. William McCurdy, Daniel S. Slaughter, and Joshua B. Williams
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Physics ,QC1-999 - Abstract
We report experimental results on three-dimensional momentum-imaging measurements of anions generated via dissociative electron attachment to gaseous formamide. From the momentum images, we analyze the angular and kinetic-energy distributions for NH_{2}^{−}, O^{−}, and H^{−} fragments and discuss the possible electron attachment and dissociation mechanisms for multiple resonances for two ranges of incident electron energies, from 5.3 to 6.8 eV and from 10.0 to 11.5 eV. Ab initio theoretical results for the angular distributions of the NH_{2}^{−} anion for ∼6-eV incident electrons, when compared with the experimental results, strongly suggest that one of the two resonances producing this fragment is a ^{2}A^{′′} Feshbach resonance.
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- 2021
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5. Photoelectron and fragmentation dynamics of the H^{+}+H^{+} dissociative channel in NH_{3} following direct single-photon double ionization
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Kirk A. Larsen, Thomas N. Rescigno, Travis Severt, Zachary L. Streeter, Wael Iskandar, Saijoscha Heck, Averell Gatton, Elio G. Champenois, Richard Strom, Bethany Jochim, Dylan Reedy, Demitri Call, Robert Moshammer, Reinhard Dörner, Allen L. Landers, Joshua B. Williams, C. William McCurdy, Robert R. Lucchese, Itzik Ben-Itzhak, Daniel S. Slaughter, and Thorsten Weber
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Physics ,QC1-999 - Abstract
We report measurements on the H^{+}+H^{+} fragmentation channel following direct single-photon double ionization of neutral NH_{3} at 61.5 eV, where the two photoelectrons and two protons are measured in coincidence using three-dimensional (3D) momentum imaging. We identify four dication electronic states that contribute to H^{+}+H^{+} dissociation, based on our multireference configuration-interaction calculations of the dication potential energy surfaces. The extracted branching ratios between these four dication electronic states are presented. Of the four dication electronic states, three dissociate in a concerted process, while the fourth undergoes a sequential fragmentation mechanism. We find evidence that the neutral NH fragment or intermediate NH^{+} ion is markedly rovibrationally excited. We also identify differences in the relative emission angle between the two photoelectrons as a function of their energy sharing for the four different dication states, which bare some similarities to previous observations made on atomic targets.
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- 2020
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6. Photoelectron Diffraction Imaging of a Molecular Breakup Using an X-Ray Free-Electron Laser
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Gregor Kastirke, Markus S. Schöffler, Miriam Weller, Jonas Rist, Rebecca Boll, Nils Anders, Thomas M. Baumann, Sebastian Eckart, Benjamin Erk, Alberto De Fanis, Kilian Fehre, Averell Gatton, Sven Grundmann, Patrik Grychtol, Alexander Hartung, Max Hofmann, Markus Ilchen, Christian Janke, Max Kircher, Maksim Kunitski, Xiang Li, Tommaso Mazza, Niklas Melzer, Jacobo Montano, Valerija Music, Giammarco Nalin, Yevheniy Ovcharenko, Andreas Pier, Nils Rennhack, Daniel E. Rivas, Reinhard Dörner, Daniel Rolles, Artem Rudenko, Philipp Schmidt, Juliane Siebert, Nico Strenger, Daniel Trabert, Isabel Vela-Perez, Rene Wagner, Thorsten Weber, Joshua B. Williams, Pawel Ziolkowski, Lothar Ph. H. Schmidt, Achim Czasch, Florian Trinter, Michael Meyer, Kiyoshi Ueda, Philipp V. Demekhin, and Till Jahnke
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Physics ,QC1-999 - Abstract
A central motivation for the development of x-ray free-electron lasers has been the prospect of time-resolved single-molecule imaging with atomic resolution. Here, we show that x-ray photoelectron diffraction—where a photoelectron emitted after x-ray absorption illuminates the molecular structure from within—can be used to image the increase of the internuclear distance during the x-ray-induced fragmentation of an O_{2} molecule. By measuring the molecular-frame photoelectron emission patterns for a two-photon sequential K-shell ionization in coincidence with the fragment ions, and by sorting the data as a function of the measured kinetic energy release, we can resolve the elongation of the molecular bond by approximately 1.2 a.u. within the duration of the x-ray pulse. The experiment paves the road toward time-resolved pump-probe photoelectron diffraction imaging at high-repetition-rate x-ray free-electron lasers.
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- 2020
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7. Trading User Data: A Blockchain Based Approach.
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Thorsten Weber and Wolfgang Prinz
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- 2019
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8. The Future of Human-AI Collaboration: A Taxonomy of Design Knowledge for Hybrid Intelligence Systems.
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Dominik Dellermann, Adrian Calma, Nikolaus Lipusch, Thorsten Weber, Sascha Weigel, and Philipp Ebel
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- 2019
9. Digitization and New Work: A Qualitative Guide for Small and Medium-Sized Enterprises to Take Action.
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Laura Wasser, Thorsten Weber, and Rüdiger Buchkremer
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- 2022
10. Humoral immune response and live-virus neutralization of the SARS-CoV-2 omicron (BA.1) variant after COVID-19 mRNA vaccination in children and young adults with chronic kidney disease
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Maximilian Stich, Veronica Di Cristanziano, Burkhard Tönshoff, Lutz Thorsten Weber, Jörg Dötsch, Marian Theodor Rammer, Susanne Rieger, Eva Heger, Sven F. Garbade, Kathrin Burgmaier, Louise Benning, Claudius Speer, Sandra Habbig, and Sophie Haumann
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Nephrology ,Pediatrics, Perinatology and Child Health - Abstract
Background Data on humoral immune response to standard COVID-19 vaccination are scarce in adolescent patients and lacking for children below 12 years of age with chronic kidney disease including kidney transplant recipients. Methods We therefore investigated in this retrospective two-center study (DRKS00024668; registered 23.03.2021) the humoral immune response to a standard two-dose mRNA vaccine regimen in 123 CKD patients aged 5–30 years. A live-virus assay was used to assess the serum neutralizing activity against the SARS-CoV-2 omicron (BA.1) variant. Results Children aged 5–11 years had a comparable rate and degree of immune response to adolescents despite lower vaccine doses (10 µg vs. 30 µg BNT162b2). Treatment with two (odds ratio 9.24) or three or more (odds ratio 17.07) immunosuppressants was an independent risk factor for nonresponse. The immune response differed significantly among three patient cohorts: 48 of 77 (62.3%) kidney transplant recipients, 21 of 26 (80.8%) patients on immunosuppressive therapy, and 19 of 20 (95.0%) patients with chronic kidney disease without immunosuppressive therapy responded. In the kidney transplant recipients, immunosuppressive regimens comprising mycophenolate mofetil, an eGFR of 2, and female sex were independent risk factors for nonresponse. Two of 18 (11.1%) and 8 of 16 (50.0%) patients with an anti-S1-RBD IgG of 100–1411 and > 1411 BAU/mL, respectively, showed a neutralization activity against the omicron variant. Conclusion A standard mRNA vaccine regimen in immunosuppressed children and adolescents with kidney disease elicits an attenuated humoral immune response with effective live virus neutralization against the omicron variant in approximately 10% of the patients, underlying the need for omicron-adapted vaccination. Graphical abstract
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- 2022
11. Repetitive administration of rituximab can achieve and maintain clinical remission in patients with MCD or FSGS
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Thomas Osterholt, Polina Todorova, Lucas Kühne, Rasmus Ehren, Lutz Thorsten Weber, Franziska Grundmann, Thomas Benzing, Paul Thomas Brinkkötter, and Linus Alexander Völker
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Multidisciplinary - Abstract
Minimal change disease (MCD) and focal segmental glomerulosclerosis (FSGS) are glomerulopathies associated with nephrotic syndrome. Primary forms of these diseases are treated with various regimes of immunosuppression. Frequently relapsing or glucocorticoid-dependent courses remain challenging. Here, a B-cell-depleting strategy with rituximab represents a salvage option although data are sparse in the adult population. In particular, there is limited evidence on the efficacy of restoring remission after initial successful treatment with rituximab and whether patients benefit from an individualized, relapse-based approach. We identified 13 patients who received multiple therapies with rituximab from the FOrMe-registry (NCT03949972), a nationwide registry for MCD and FSGS in Germany, or from the University Hospital of Cologne. Disease status, changes in serum creatinine, proteinuria, and time to relapse were evaluated. Relapse-free survival was compared to the patients’ previous therapy regimens. Through all treatment cycles, an improvement of disease activity was shown leading to a complete remission in 72% and partial remission in 26% after 3 ($$p p < 0.001) and 6 months ($$p p < 0.001). Relapse-free survival increased from 4.5 months (95%-CI 3–10 months) to 21 months (95%-CI 16–32 months) ($$p p < 0.001) compared to previous immunosuppression regimens with no loss in estimated glomerular filtration over time (p = 0.53). Compared to continuous B-cell depletion, an individualized relapse-based approach led to a reduced rituximab exposure and significant cost savings. Relapse-based administration of rituximab in patients with MCD/FSGS with an initial good clinical response did not result in a decreased efficacy at a median follow-up duration of 110 months. Thus, reinduction therapies may provide an alternative to continuous B-cell-depletion and reduce the long-term side effects of continuous immunosuppression.
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- 2023
12. Electron and Positron Scattering Cross Sections from CO
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Ana I, Lozano, Adrián, García-Abenza, Francisco, Blanco Ramos, Mahmudul, Hasan, Daniel S, Slaughter, Thorsten, Weber, Robert P, McEachran, Ronald D, White, Michael J, Brunger, Paulo, Limão-Vieira, and Gustavo, García Gómez-Tejedor
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In this Review, we present a comparative study between electron and positron scattering cross sections from CO
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- 2022
13. AB INITIO MODELING OF ULTRAFAST NONLINEAR OPTICAL SIGNALS IN MOLECULAR SYSTEMS INVOLVING ELECTRONIC TRANSITIONS
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Richard Thurston, Daniel Slaughter, Liang Tan, and Thorsten Weber
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- 2022
14. Clinical Aspects of the Subsequent SARS-CoV-2 Waves in Children from 2020 to 2022-Data from a Local Cohort in Cologne, Germany (
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Meike, Meyer, Esra, Ruebsteck, Felix, Dewald, Florian, Klein, Clara, Lehmann, Christoph, Huenseler, and Lutz Thorsten, Weber
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COVID-19 Testing ,Adolescent ,SARS-CoV-2 ,Child, Preschool ,Germany ,Infant, Newborn ,COVID-19 ,Humans ,Infant ,Child ,Retrospective Studies - Abstract
Almost two and a half years after the appearance of the first cases of SARS-CoV-2 in December 2019, more than 500 million people have been infected with SARS-CoV-2 and over 6 million have died of it worldwide. In terms of the pediatric cohort, it already became evident at an early stage that the infection causes milder symptoms in children and rarely runs a fatal course.This work presents data gathered over a period of over two years in patients between the age of 0 and 18 years. The aim is to provide information on the clinical aspects of the five different SARS-CoV-2 waves.Between 13 March 2020 and 22 April 2022, all nucleic acid amplification tests (NAATs) of children who received a swab for SARS-CoV-2 at our clinic were included. Data were collected on standardized questionnaires. The analysis of the data was anonymized and retrospective.We investigated 21,635 NAATs, of which 1028 of the tests were positive (4.8%). The highest rate of positive results was observed in the fifth wave (541/2.292 NAATs (23.6%)). Most of the children who were hospitalized were hospitalized in wave three (22.9%). The availability of a vaccine was followed by a decrease in positive NAATs in the corresponding age group thereafter.These data underline the fact that children infected with SARS-CoV-2, regardless of which VOC, are often only mildly affected. Vaccinations seem to remain the key to avoid massive numbers of infected people and a potential collapse of the healthcare systems.
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- 2022
15. From an E-Business Revenue Model to Its Software Reference Architecture.
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Volker Gruhn and Thorsten Weber
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- 2005
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16. Dynamics of dissociative electron attachment to model peptides
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Joshua Williams, Thomas Rescigno, Sylwia Ptasinska, Dipayan Chakraborty, C McCurdy, Thorsten Weber, Kyle Swanson, Brandon Griffin, Ali Moradmand, Guglielmo Panelli, and Daniel Slaughter
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- 2022
17. A kinematically complete measurement of the direct photo double ionization of ethylene molecules
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Thorsten Weber, Daniel Slaughter, Sun Lee, Wael Iskandar, and Moniruzzaman Shaikh
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- 2022
18. Phenotypic Variability in Siblings With Autosomal Recessive Polycystic Kidney Disease
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Ramona Ajiri, Kathrin Burgmaier, Nurver Akinci, Ilse Broekaert, Anja Büscher, Ismail Dursun, Ali Duzova, Loai Akram Eid, Marc Fila, Michaela Gessner, Ibrahim Gokce, Laura Massella, Antonio Mastrangelo, Monika Miklaszewska, Larisa Prikhodina, Bruno Ranchin, Nadejda Ranguelov, Rina Rus, Lale Sever, Julia Thumfart, Lutz Thorsten Weber, Elke Wühl, Alev Yilmaz, Jörg Dötsch, Franz Schaefer, Max Christoph Liebau, UCL - (SLuc) Département de pédiatrie, UCL - SSS/IREC/PEDI - Pôle de Pédiatrie, UCL - (SLuc) Service de pédiatrie générale, and Ajiri R., Burgmaier K., Akinci N., Broekaert I., Büscher A., Dursun I., Duzova A., Eid L. A., Fila M., Gessner M., et al.
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Internal Diseases ,LIVER ,GENETICS ,ARPKD ,Medizin ,CHILDREN ,PKHD1 ,Sağlık Bilimleri ,İç Hastalıkları ,Clinical Medicine (MED) ,CONGENITAL HEPATIC-FIBROSIS ,UROLOGY & NEPHROLOGY ,Health Sciences ,Fibrocystin ,Klinik Tıp (MED) ,ÜROLOJİ VE NEFROLOJİ ,PRENATAL-DIAGNOSIS ,Internal Medicine Sciences ,Klinik Tıp ,RENAL-TRANSPLANTATION ,MUTATIONS ,PKD ,Dahili Tıp Bilimleri ,CLINICAL MEDICINE ,Ciliopathies ,Tıp ,CLINICAL-EXPERIENCE ,Nefroloji ,Nephrology ,DZIP1L ,Medicine - Abstract
© 2022 International Society of NephrologyIntroduction: Autosomal recessive polycystic kidney disease (ARPKD) is a rare monogenic disorder characterized by early onset fibrocystic hepatorenal changes. Previous reports have documented pronounced phenotypic variability even among siblings in terms of patient survival. The underlying causes for this clinical variability are incompletely understood. Methods: We present the longitudinal clinical courses of 35 sibling pairs included in the ARPKD registry study ARegPKD, encompassing data on primary manifestation, prenatal and perinatal findings, genetic testing, and family history, including kidney function, liver involvement, and radiological findings. Results: We identified 70 siblings from 35 families with a median age of 0.7 (interquartile range 0.1–6.0) years at initial diagnosis and a median follow-up time of 3.5 (0.2–6.2) years. Data on PKHD1 variants were available for 37 patients from 21 families. There were 8 patients from 7 families who required kidney replacement therapy (KRT) during follow-up. For 44 patients from 26 families, antihypertensive therapy was documented. Furthermore, 37 patients from 24 families had signs of portal hypertension with 9 patients from 6 families having substantial hepatic complications. Interestingly, pronounced variability in the clinical course of functional kidney disease was documented in only 3 sibling pairs. In 17 of 20 families of our cohort of neonatal survivors, siblings had only minor differences of kidney function at a comparable age. Conclusion: In patients surviving the neonatal period, our longitudinal follow-up of 70 ARPKD siblings from 35 families revealed comparable clinical courses of kidney and liver diseases in most families. The data suggest a strong impact of the underlying genotype.
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- 2022
19. Mathematik erleben um zu lernen – das Erkundungskonzept für die Vorlesung Arithmetik und Geometrie im Lehramtsstudium für die Grundschule
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Andreas Eichler, Elisabeth Rathgeb-Schnierer, and Thorsten Weber
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- 2022
20. IPNA clinical practice recommendations for the diagnosis and management of children with steroid-sensitive nephrotic syndrome
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Trautmann, Agnes, Boyer, Olivia, Hodson, Elisabeth, Bagga, Arvind, Gipson, Debbie S., Samuel, Susan, Wetzels, Jack, Alhasan, Khalid, Banerjee, Sushmita, Bhimma, Rajendra, Bonilla-Felix, Melvin, Cano, Francisco, Christian, Martin, Hahn, Deirdre, Kang, Hee Gyung, Nakanishi, Koichi, Safouh, Hesham, Trachtman, Howard, Xu, Hong, Cook, Wendy, Vivarelli, Marina, Haffner, Dieter, Bouts, Antonia, Dossier, Claire, Emma, Francesco, Kemper, Markus, Topaloglu, Rezan, Waters, Aoife, Thorsten Weber, Lutz, Zurowska, Alexandra, Gibson, Keisha L., Greenbaum, Larry, Massengill, Susan, Selewski, David, Srivastava, Tarak, Wang, Chia-shi, Wenderfer, Scott, Johnstone, Lilian, Larkins, Nicholas, Wong, William, Alba, Agnes A., Ha, T. S., Mokham, Masoumeh, Zhong, Xuhui, Hamada, Riku, Iijima, Kazumoto, Ishikura, Kenji, Nozu, Kandai, Bresolin, Nilzete, de Jesus Gonzalez, Nilka, Restrepo, Jaime, Anochie, Ifeoma, McCulloch, Mignon, Pediatrics, Paediatric Nephrology, ARD - Amsterdam Reproduction and Development, and AII - Amsterdam institute for Infection and Immunity
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Steroid-sensitive nephrotic syndrome ,All institutes and research themes of the Radboud University Medical Center ,Frequently relapsing nephrotic syndrome ,Nephrology ,Steroid toxicity ,Pediatrics, Perinatology and Child Health ,SSNS ,Steroid-dependent nephrotic syndrome ,Renal disorders Radboud Institute for Health Sciences [Radboudumc 11] ,Children ,Pediatrics ,Immunosuppressive treatment - Abstract
Contains fulltext : 290812.pdf (Publisher’s version ) (Open Access) Idiopathic nephrotic syndrome is the most frequent pediatric glomerular disease, affecting from 1.15 to 16.9 per 100,000 children per year globally. It is characterized by massive proteinuria, hypoalbuminemia, and/or concomitant edema. Approximately 85-90% of patients attain complete remission of proteinuria within 4-6 weeks of treatment with glucocorticoids, and therefore, have steroid-sensitive nephrotic syndrome (SSNS). Among those patients who are steroid sensitive, 70-80% will have at least one relapse during follow-up, and up to 50% of these patients will experience frequent relapses or become dependent on glucocorticoids to maintain remission. The dose and duration of steroid treatment to prolong time between relapses remains a subject of much debate, and patients continue to experience a high prevalence of steroid-related morbidity. Various steroid-sparing immunosuppressive drugs have been used in clinical practice; however, there is marked practice variation in the selection of these drugs and timing of their introduction during the course of the disease. Therefore, international evidence-based clinical practice recommendations (CPRs) are needed to guide clinical practice and reduce practice variation. The International Pediatric Nephrology Association (IPNA) convened a team of experts including pediatric nephrologists, an adult nephrologist, and a patient representative to develop comprehensive CPRs on the diagnosis and management of SSNS in children. After performing a systematic literature review on 12 clinically relevant PICO (Patient or Population covered, Intervention, Comparator, Outcome) questions, recommendations were formulated and formally graded at several virtual consensus meetings. New definitions for treatment outcomes to help guide change of therapy and recommendations for important research questions are given.
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- 2022
21. DEVELOPING BELIEFS IN ELEMENTARY TEACHER STUDENTS
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Thorsten Weber, Andreas Eichler, and Elisabeth Rathgeb-Schnierer
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- 2021
22. APPLYING AUGMENTED REALITY ON SMART GLASSES TO MINIMIZE HUMAN ERROR IN HANDS-FREE TECHNICAL TRAINING
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Rüdiger Buchkremer and Thorsten Weber
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Hands free ,Computer science ,Human–computer interaction ,Human error ,Technical training ,Augmented reality - Published
- 2021
23. Professionsbezogene Anforderungen und Hochschulmathematik : Kontinuitätsüberzeugungen angehender Grundschullehrkräfte im ersten Semester
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Thorsten Weber and Thorsten Weber
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- Teachers—Training of, Mathematics—Study and teaching, Schools
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Im Fokus der Arbeit steht der Übergang von der Schule zur Hochschule, explizit die Überzeugungen der Studierenden zum Zusammenhang zwischen Schulmathematik und Hochschulmathematik sowie die Überzeugungen der Studierenden zur Relevanz der Hochschulmathematik für die zukünftige Lehrtätigkeit. Neben einer theoretisch fundierten Begriffsbildung rund um die Problematik der doppelten Diskontinuität basieren die Erkenntnisse der Studie auf quantitativen Daten, die mittels Fragebogen zu Beginn des Studiums und zum Ende des ersten Semesters an drei deutschen Universitäten erhoben wurden. Übergeordnetes Ziel ist es herauszuarbeiten, mit welchen Kontinuitätsüberzeugungen Grundschullehramtsstudierende ins Studium starten und welchen Einfluss das erste Semester auf diese Überzeugungen hat. Die Daten zeigen, dass die Problematik der doppelten Diskontinuität im Grundschullehramtsstudium aktuell ist und auch schon zu Studienbeginn von der Universität abhängen könnte, an der studiert wird. Zudem zeigt die Studie vielfältige Ergebnisse zu bestimmten Überzeugungen, zu denen auch Wechselwirkungen zwischen Überzeugungen und Studium analysiert werden.
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- 2024
24. Monitoring Remote Service Platforms Using Artificial IntelligenceBased Distributed Intrusion Detection
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Thorsten Weber and Rüdiger Buchkremer
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Service (business) ,Computer science ,business.industry ,Distributed intrusion detection ,business ,Computer network - Abstract
Monitoring Remote Service Platforms Using Artificial IntelligenceBased Distributed Intrusion Detection
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- 2021
25. The future of human-AI collaboration: a taxonomy of design knowledge for hybrid intelligence systems
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Thorsten Weber, Philipp Ebel, Sascha Weigel, Adrian Calma, Dominik Dellermann, and Nikolaus Lipusch
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Information management ,FOS: Computer and information sciences ,Structured analysis ,Computer Science - Artificial Intelligence ,Computer science ,05 social sciences ,Computer Science - Human-Computer Interaction ,artificial intelligence, human-ai interaction, human-in-the-loop, hybrid intelligence, machine learning ,information management ,02 engineering and technology ,Design knowledge ,Data science ,Pipeline (software) ,050105 experimental psychology ,Field (computer science) ,Human-Computer Interaction (cs.HC) ,Artificial Intelligence (cs.AI) ,business studies ,Artificial general intelligence ,Taxonomy (general) ,0202 electrical engineering, electronic engineering, information engineering ,Systems design ,020201 artificial intelligence & image processing ,0501 psychology and cognitive sciences ,other research area - Abstract
Recent technological advances, especially in the field of machine learning, provide astonishing progress on the road towards artificial general intelligence. However, tasks in current real-world business applications cannot yet be solved by machines alone. We, therefore, identify the need for developing socio-technological ensembles of humans and machines. Such systems possess the ability to accomplish complex goals by combining human and artificial intelligence to collectively achieve superior results and continuously improve by learning from each other. Thus, the need for structured design knowledge for those systems arises. Following a taxonomy development method, this article provides three main contributions: First, we present a structured overview of interdisciplinary research on the role of humans in the machine learning pipeline. Second, we envision hybrid intelligence systems and conceptualize the relevant dimensions for system design for the first time. Finally, we offer useful guidance for system developers during the implementation of such applications.
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- 2021
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26. High-Resolution Momentum Imaging—From Stern’s Molecular Beam Method to the COLTRIMS Reaction Microscope
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K. Ullmann, J. Ullrich, M. H. Prior, Lutz Spielberger, S. Voss, V. Frohne, T. Jahnke, R. Moshammer, Rami Ali, Alexander Dorn, V. Mergel, Markus Schöffler, S. Schößler, L. Schmidt, Allen Landers, Achim Czasch, Michael Schulz, R E Olson, Daniel Fischer, Horst Schmidt-Böcking, Reinhard Dörner, Sebastian Eckart, C. L. Cocke, Thorsten Weber, and Ottmar Jagutzki
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Physics ,Microscope ,Photon ,Measure (physics) ,Electron ,01 natural sciences ,010305 fluids & plasmas ,Computational physics ,law.invention ,Momentum ,law ,Quantum process ,0103 physical sciences ,Particle ,010306 general physics ,Molecular beam - Abstract
Multi-particle momentum imaging experiments are now capable of providing detailed information on the properties and the dynamics of quantum systems in Atomic, Molecular and Photon (AMO) physics. Historically, Otto Stern can be considered the pioneer of high-resolution momentum measurements of particles moving in a vacuum and he was the first to obtain sub-atomic unit (a.u.) momentum resolution (Schmidt-Böcking et al. in The precision limits in a single-event quantum measurement of electron momentum and position, these proceedings [1]). A major contribution to modern experimental atomic and molecular physics was his so-called molecular beam method [2], which Stern developed and employed in his experiments. With this method he discovered several fundamental properties of atoms, molecules and nuclei [2, 3]. As corresponding particle detection techniques were lacking during his time, he was only able to observe the averaged footprints of large particle ensembles. Today it is routinely possible to measure the momenta of single particles, because of the tremendous progress in single particle detection and data acquisition electronics. A “state-of-the-art” COLTRIMS reaction microscope [4–11] can measure, for example, the momenta of several particles ejected in the same quantum process in coincidence with sub-a.u. momentum resolution. Such setups can be used to visualize the dynamics of quantum reactions and image the entangled motion of electrons inside atoms and molecules. This review will briefly summarize Stern’s work and then present in longer detail the historic steps of the development of the COLTRIMS reaction microscope. Furthermore, some benchmark results are shown which initially paved the way for a broad acceptance of the COLTRIMS approach. Finally, a small selection of milestone work is presented which has been performed during the last two decades.
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- 2021
27. Role of dipole-forbidden autoionizing resonances in nonresonant one-color two-photon single ionization of N2
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C. William McCurdy, Thomas N. Rescigno, Roger Y. Bello, Daniel Slaughter, Thorsten Weber, Kirk A. Larsen, and Robert R. Lucchese
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Physics ,Photon ,Photoionization ,Photoelectric effect ,Kinetic energy ,01 natural sciences ,010305 fluids & plasmas ,Ion ,Dipole ,Ionization ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Physics::Atomic Physics ,Atomic physics ,010306 general physics ,Excitation - Abstract
We present an experimental and theoretical energy- and angle-resolved study on the photoionization dynamics of nonresonant one-color two-photon single-valence ionization of neutral ${\mathrm{N}}_{2}$ molecules. Using 9.3-eV photons produced via high-order harmonic generation and a three-dimensional momentum imaging spectrometer, we detect the photoelectrons and ions produced from one-color two-photon ionization in coincidence. Photoionization of ${\mathrm{N}}_{2}$ populates the $X$ $^{2}\mathrm{\ensuremath{\Sigma}}_{g}^{+}, A$ $^{2}\mathrm{\ensuremath{\Pi}}_{u}$, and $B$ $^{2}\mathrm{\ensuremath{\Sigma}}_{u}^{+}$ ionic states of ${\mathrm{N}}_{2}{}^{+}$, where the photoelectron angular distributions associated with the $X$ $^{2}\mathrm{\ensuremath{\Sigma}}_{g}^{+}$ and $A$ $^{2}\mathrm{\ensuremath{\Pi}}_{u}$ states both vary with changes in photoelectron kinetic energy of only a few hundred meV. We attribute the rapid evolution in the photoelectron angular distributions to the excitation and decay of dipole-forbidden autoionizing resonances that belong to series of different symmetries, all of which are members of the Hopfield series, and compete with the direct two-photon single ionization.
- Published
- 2020
28. A Generic Approach for the Automated Notarization of Cloud Configurations Using Blockchain-Based Trust
- Author
-
Thorsten Weber and Thorsten Weber
- Subjects
- Technological innovations, Business enterprises—Finance, Financial risk management
- Abstract
The use of cloud applications is becoming increasingly popular due to their scalability and cost advantages. However, companies need help in adopting cloud applications due to their internal policies and compliance requirements. Trust and security are crucial factors that influence the adoption of cloud applications. This book proposes a cloud architecture that addresses this challenge by shifting the trust for compliance-driven configurations of cloud applications from the cloud application provider to the blockchain. The architecture was developed using design science research and evaluated using mixed-method semi-structured guided interviews. The results show that the proposed architecture can significantly reduce adoption risk due to compliance-driven cloud application configurations, shifting trust from the cloud provider to the blockchain. This book presents an innovative approach to address the challenge of adopting cloud applications, and enhancing trust and security for businesses.
- Published
- 2023
29. Double Core-Hole Generation in O2 Molecules Using an X-Ray Free-Electron Laser: Molecular-Frame Photoelectron Angular Distributions
- Author
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Philipp V. Demekhin, Kiyoshi Ueda, Sebastian Eckart, Alexander Hartung, Florian Trinter, Benjamin Erk, Averell Gatton, Daniel Rolles, D. Trabert, Nico Strenger, Michael Meyer, Rene Wagner, Andreas Pier, Isabel Vela-Perez, Philipp Schmidt, Jacobo Montaño, G. Nalin, Y. Ovcharenko, Rebecca Boll, Nils Anders, Patrik Grychtol, Artem Rudenko, Thorsten Weber, K. Fehre, Tommaso Mazza, Sven Grundmann, Lothar Ph. H. Schmidt, Maksim Kunitski, Daniel E. Rivas, Juliane Siebert, V. Music, Nils Rennhack, T. M. Baumann, Markus Ilchen, M. Weller, Markus Schöffler, Jonas Rist, Joshua B. Williams, Max Kircher, Till Jahnke, Alberto De Fanis, G. Kastirke, Reinhard Dörner, Achim Czasch, C. Janke, M. Hofmann, Xiang Li, Pawel Ziolkowski, and Niklas Melzer
- Subjects
Core (optical fiber) ,Materials science ,Microscope ,law ,X-ray ,Free-electron laser ,General Physics and Astronomy ,Molecule ,Electron ,Laser ,Molecular physics ,law.invention ,Ion - Abstract
We report on a multiparticle coincidence experiment performed at the European X-ray Free-Electron Laser at the Small Quantum Systems instrument using a COLTRIMS reaction microscope. By measuring two ions and two electrons in coincidence, we investigate double core-hole generation in O_{2} molecules in the gas phase. Single-site and two-site double core holes have been identified and their molecular-frame electron angular distributions have been obtained for a breakup of the oxygen molecule into two doubly charged ions. The measured distributions are compared to results of calculations performed within the frozen- and relaxed-core Hartree-Fock approximations.
- Published
- 2020
30. Photoelectron and fragmentation dynamics of the H++H+ dissociative channel in NH3 following direct single-photon double ionization
- Author
-
Itzik Ben-Itzhak, Robert R. Lucchese, Bethany Jochim, Richard Strom, Joshua B. Williams, Elio G. Champenois, Wael Iskandar, Robert Moshammer, Thomas N. Rescigno, Reinhard Dörner, Zachary L. Streeter, Daniel Slaughter, Kirk A. Larsen, Saijoscha Heck, Travis Severt, Demitri Call, C. William McCurdy, D. Reedy, Thorsten Weber, Averell Gatton, and Allen L. Landers
- Subjects
Physics ,010304 chemical physics ,Double ionization ,Photoelectric effect ,01 natural sciences ,Potential energy ,Dissociation (chemistry) ,Dication ,Ion ,Fragmentation (mass spectrometry) ,Excited state ,0103 physical sciences ,Atomic physics ,010306 general physics - Abstract
Author(s): Larsen, KA; Rescigno, TN; Severt, T; Streeter, ZL; Iskandar, W; Heck, S; Gatton, A; Champenois, EG; Strom, R; Jochim, B; Reedy, D; Call, D; Moshammer, R; Dorner, R; Landers, AL; Williams, JB; McCurdy, CW; Lucchese, RR; Ben-Itzhak, I; Slaughter, DS; Weber, T | Abstract: We report measurements on the H++H+ fragmentation channel following direct single-photon double ionization of neutral NH3 at 61.5 eV, where the two photoelectrons and two protons are measured in coincidence using three-dimensional (3D) momentum imaging. We identify four dication electronic states that contribute to H++H+ dissociation, based on our multireference configuration-interaction calculations of the dication potential energy surfaces. The extracted branching ratios between these four dication electronic states are presented. Of the four dication electronic states, three dissociate in a concerted process, while the fourth undergoes a sequential fragmentation mechanism. We find evidence that the neutral NH fragment or intermediate NH+ ion is markedly rovibrationally excited. We also identify differences in the relative emission angle between the two photoelectrons as a function of their energy sharing for the four different dication states, which bare some similarities to previous observations made on atomic targets.
- Published
- 2020
31. Distinguishing resonance symmetries with energy-resolved photoion angular distributions from ion-pair formation in O
- Author
-
Kirk A, Larsen, Robert R, Lucchese, Daniel S, Slaughter, and Thorsten, Weber
- Abstract
We present a combined experimental and theoretical study on the photodissociation dynamics of ion-pair formation in O
- Published
- 2020
32. REIMAGINING OF OPTICAL KERR EFFECT SPECTROSCOPY: DEVELOPMENT OF A NEW SPECTROSCOPIC TECHNIQUE
- Author
-
Niranjan Shivaram, Matthew M. Brister, Liang Tan, Thorsten Weber, Richard Thurston, and Daniel Slaughter
- Subjects
Materials science ,Kerr effect ,business.industry ,Optoelectronics ,business ,Spectroscopy - Published
- 2020
33. Time-resolved ultrafast transient polarization spectroscopy to investigate nonlinear processes and dynamics in electronically excited molecules on the femtosecond time scale
- Author
-
Ali Belkacem, Niranjan Shivaram, Daniel Slaughter, Thorsten Weber, Richard Thurston, and Matthew M. Brister
- Subjects
Chemical Physics (physics.chem-ph) ,010302 applied physics ,Kerr effect ,Materials science ,physics.chem-ph ,FOS: Physical sciences ,Physics::Optics ,Polarization (waves) ,01 natural sciences ,010305 fluids & plasmas ,Nonlinear system ,Engineering ,Excited state ,Physics - Chemical Physics ,0103 physical sciences ,Femtosecond ,Physical Sciences ,Chemical Sciences ,Molecule ,Atomic physics ,Spectroscopy ,Instrumentation ,Ultrashort pulse ,Applied Physics - Abstract
We report a novel experimental technique to investigate ultrafast dynamics in photoexcited molecules by probing the third-order nonlinear optical susceptibility. A non-colinear 3-pulse scheme is developed to probe the ultrafast dynamics of excited electronic states using the optical Kerr effect by time-resolved polarization spectroscopy. Optical heterodyne and optical homodyne detection are demonstrated to measure the third-order nonlinear optical response for the S1 excited state of liquid nitrobenzene, which is populated by 2-photon absorption of a 780 nm 35 fs excitation pulse., 12 pages, 4 figures. Changes from previous version: added panel labels to figures 3-4
- Published
- 2020
34. Angle-resolved non-resonant two-photon single ionization of argon using 9.3 eV photons produced via high harmonic generation
- Author
-
Thorsten Weber, Kirk A. Larsen, and Daniel Slaughter
- Subjects
Physics ,Quantum Physics ,Argon ,Photon ,Scattering ,Atomic Physics (physics.atom-ph) ,chemistry.chemical_element ,FOS: Physical sciences ,Photoionization ,Photoelectric effect ,01 natural sciences ,010305 fluids & plasmas ,Ion ,Physics - Atomic Physics ,chemistry ,Ionization ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,High harmonic generation ,Physics::Atomic Physics ,Atomic physics ,010306 general physics ,Quantum Physics (quant-ph) ,Optics (physics.optics) ,Physics - Optics - Abstract
We present an experimental study on the photoionization dynamics of non-resonant one-color two-photon single valence ionization of neutral argon atoms. Using 9.3 eV photons produced via high harmonic generation and a 3-D momentum imaging spectrometer, we detect the photoelectrons and ions produced from non-resonant two-photon ionization in coincidence. Photoionization from the $3p$ orbital produces a photoelectron scattering wave function with $p$ and $f$ partial wave components, which interfere and result in a photoelectron angular distribution with peak amplitude perpendicular to the VUV polarization. The comparison between the present results and two previous sets of theoretical calculations [Pan, C. & Starace, A. F. (1991). $\textit{Physical Review A}$, 44(1), 324., and Moccia, R., Rahman, N. K., & Rizzo, A. (1983). $\textit{Journal of Physics B: Atomic and Molecular Physics}$, 16(15), 2737.] indicates that electron-electron correlation contributes appreciably to the two-photon ionization dynamics., 7 pages, 4 figures, 1 table
- Published
- 2020
35. Mechanisms and dynamics of the NH$_2^{+}$ + H$^{+}$ and NH$^{+}$ + H$^{+}$ + H fragmentation channels upon single-photon double ionization of NH$_3$
- Author
-
Saijoscha Heck, Bethany Jochim, Zachary L. Streeter, D. Reedy, Averell Gatton, Thorsten Weber, Thomas N. Rescigno, Allen Landers, Kirk A. Larsen, Travis Severt, Robert R. Lucchese, Demitri Call, Wael Iskandar, C. William McCurdy, Robert Moshammer, Reinhard Dörner, Elio G. Champenois, Richard Strom, Daniel Slaughter, Joshua B. Williams, and Itzik Ben-Itzhak
- Subjects
double ionization ,intersystem crossing ,Atomic Physics (physics.atom-ph) ,Double ionization ,physics.chem-ph ,FOS: Physical sciences ,autoionization ,Photoionization ,physics.atom-ph ,01 natural sciences ,Dissociation (chemistry) ,Physics - Atomic Physics ,010305 fluids & plasmas ,Fragmentation (mass spectrometry) ,Autoionization ,Physics - Chemical Physics ,0103 physical sciences ,010306 general physics ,photoionization ,Physics ,Chemical Physics (physics.chem-ph) ,non-adiabatic dynamics ,photodissociation ,Optics ,Condensed Matter Physics ,Atomic and Molecular Physics, and Optics ,3. Good health ,Dication ,Intersystem crossing ,Excited state ,COLTRIMS ,Atomic physics - Abstract
We present state-selective measurements on the NH$_2^{+}$ + H$^{+}$ and NH$^{+}$ + H$^{+}$ + H dissociation channels following single-photon double ionization at 61.5 eV of neutral NH$_{3}$, where the two photoelectrons and two cations are measured in coincidence using 3-D momentum imaging. Three dication electronic states are identified to contribute to the NH$_2^{+}$ + H$^{+}$ dissociation channel, where the excitation in one of the three states undergoes intersystem crossing prior to dissociation, producing a cold NH$_2^+$ fragment. In contrast, the other two states directly dissociate, producing a ro-vibrationally excited NH$_2^+$ fragment with roughly 1 eV of internal energy. The NH$^{+}$ + H$^{+}$ + H channel is fed by direct dissociation from three intermediate dication states, one of which is shared with the NH$_2^{+}$ + H$^{+}$ channel. We find evidence of autoionization contributing to each of the double ionization channels. The distributions of the relative emission angle between the two photoelectrons, as well as the relative angle between the recoil axis of the molecular breakup and the polarization vector of the ionizing field, are also presented to provide insight on both the photoionization and photodissociation mechanisms for the different dication states., Comment: 18 pages, 21 figures, 3 tables
- Published
- 2020
- Full Text
- View/download PDF
36. Investigating resonant low-energy electron attachment to formamide: dynamics of model peptide bond dissociation and other fragmentation channels
- Author
-
Ali Moradmand, Guglielmo Panelli, Brandon Griffin, C. William McCurdy, Thomas N. Rescigno, Kyle Swanson, Daniel Slaughter, Thorsten Weber, and Joshua B. Williams
- Subjects
Physics ,Formamide ,Chemical Physics (physics.chem-ph) ,Atomic Physics (physics.atom-ph) ,physics.chem-ph ,Ab initio ,FOS: Physical sciences ,Electron ,Molecular physics ,physics.atom-ph ,Dissociation (psychology) ,Physics - Atomic Physics ,Ion ,Momentum ,chemistry.chemical_compound ,chemistry ,Fragmentation (mass spectrometry) ,Computer Science::Systems and Control ,Physics - Chemical Physics ,medicine ,medicine.symptom ,Feshbach resonance ,Astrophysics::Galaxy Astrophysics - Abstract
We report experimental results on three-dimensional momentum imaging measurements of anions generated via dissociative electron attachment to gaseous formamide. From the momentum images, we analyze the angular and kinetic energy distributions for NH$_2^{-}$, O$^{-}$, and H$^{-}$ fragments and discuss the possible electron attachment and dissociation mechanisms for multiple resonances for two ranges of incident electron energies, from 5.3~eV to 6.8~eV, and from 10.0~eV to 11.5~eV. {\it Ab initio} theoretical results for the angular distributions of the NH$_2^{-}$ anion for $\sim$6~eV incident electrons, when compared with the experimental results, strongly suggest that one of the two resonances producing this fragment is a $^2$A$''$ Feshbach resonance., Comment: 10 pages, 6 figures
- Published
- 2020
- Full Text
- View/download PDF
37. Photoelectron Diffraction Imaging of a Molecular Breakup Using an X-Ray Free-Electron Laser
- Author
-
Jonas Rist, Reinhard Dörner, Thorsten Weber, Averell Gatton, Y. Ovcharenko, Lothar Ph. H. Schmidt, Philipp V. Demekhin, Isabel Vela-Perez, C. Janke, Benjamin Erk, Rene Wagner, M. Hofmann, Andreas Pier, Niklas Melzer, Markus Ilchen, Sebastian Eckart, Patrik Grychtol, Juliane Siebert, M. Weller, Max Kircher, Nils Rennhack, Artem Rudenko, Maksim Kunitski, Markus Schöffler, Nils Anders, Xiang Li, Achim Czasch, Sven Grundmann, Michael Meyer, Kiyoshi Ueda, Joshua B. Williams, Philipp Schmidt, Till Jahnke, Alexander Hartung, Florian Trinter, Alberto De Fanis, Daniel Rolles, Rebecca Boll, Pawel Ziolkowski, V. Music, G. Kastirke, D. Trabert, T. M. Baumann, Nico Strenger, K. Fehre, Tommaso Mazza, Daniel E. Rivas, G. Nalin, and Jacobo Montaño
- Subjects
Diffraction ,QC1-999 ,Astrophysics::High Energy Astrophysical Phenomena ,Analytical chemistry ,General Physics and Astronomy ,Kinetic energy ,01 natural sciences ,010305 fluids & plasmas ,Ion ,law.invention ,law ,Ionization ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Molecule ,ddc:530 ,Physics::Atomic Physics ,010306 general physics ,Physics ,Quantum Physics ,X-ray ,Free-electron laser ,Laser ,Condensed Matter Physics ,Biomedical Imaging ,Astronomical and Space Sciences - Abstract
Physical review / X Expanding access 10(2), 021052 (2020). doi:10.1103/PhysRevX.10.021052, A central motivation for the development of x-ray free-electron lasers has been the prospect of time-resolved single-molecule imaging with atomic resolution. Here, we show that x-ray photoelectron diffraction—where a photoelectron emitted after x-ray absorption illuminates the molecular structure from within—can be used to image the increase of the internuclear distance during the x-ray-induced fragmentation of an O$_2$ molecule. By measuring the molecular-frame photoelectron emission patterns for a two-photon sequential $K$-shell ionization in coincidence with the fragment ions, and by sorting the data as a function of the measured kinetic energy release, we can resolve the elongation of the molecular bond by approximately 1.2 a.u. within the duration of the x-ray pulse. The experiment paves the road toward time-resolved pump-probe photoelectron diffraction imaging at high-repetition-rate x-ray free-electron lasers., Published by APS, College Park, Md.
- Published
- 2020
- Full Text
- View/download PDF
38. Ultrafast dynamics of excited electronic states in nitrobenzene measured by ultrafast transient polarization spectroscopy
- Author
-
Daniel Slaughter, Thorsten Weber, Richard Thurston, Ali Belkacem, Elio G. Champenois, Niranjan Shivaram, Matthew M. Brister, Pavan Muddukrishna, Liang Z. Tan, and Said Bakhti
- Subjects
Kerr effect ,Dephasing ,Wave packet ,physics.chem-ph ,FOS: Physical sciences ,010402 general chemistry ,01 natural sciences ,Atomic ,Physical Chemistry ,Particle and Plasma Physics ,quant-ph ,Theoretical and Computational Chemistry ,Physics - Chemical Physics ,0103 physical sciences ,Nuclear ,Physical and Theoretical Chemistry ,Spectroscopy ,Chemical Physics (physics.chem-ph) ,Quantum Physics ,010304 chemical physics ,Chemistry ,Molecular ,0104 chemical sciences ,Intersystem crossing ,Excited state ,Femtosecond ,physics.optics ,Atomic physics ,Quantum Physics (quant-ph) ,Ultrashort pulse ,Physics - Optics ,Physical Chemistry (incl. Structural) ,Optics (physics.optics) - Abstract
We investigate ultrafast dynamics of the lowest singlet excited electronic state in liquid nitrobenzene using Ultrafast Transient Polarization Spectroscopy (UTPS), extending the well-known technique of Optical-Kerr Effect (OKE) spectroscopy to excited electronic states. The third-order non-linear response of the excited molecular ensemble is highly sensitive to details of excited state character and geometries and is measured using two femtosecond pulses following a third femtosecond pulse that populates the S1 excited state. By measuring this response as a function of time delays between the three pulses involved, we extract the dephasing time of the wave-packet on the excited state. The dephasing time measured as a function of time-delay after pump excitation shows oscillations indicating oscillatory wave-packet dynamics on the excited state. From the experimental measurements and supporting theoretical calculations, we deduce that the wave-packet completely leaves the S1 state surface after three traversals of the inter-system crossing between the singlet S1 and triplet T2 states., Comment: Manuscript 15 pages, 4 figures, 1 table. Supporting Information 5 pages
- Published
- 2019
- Full Text
- View/download PDF
39. Distinguishing resonance symmetries with energy-resolved photoion angular distributions from ion-pair formation in O2 following two-photon absorption of a 9.3 eV femtosecond pulse
- Author
-
Daniel Slaughter, Kirk A. Larsen, Thorsten Weber, and Robert R. Lucchese
- Subjects
physics.chem-ph ,FOS: Physical sciences ,General Physics and Astronomy ,010402 general chemistry ,Kinetic energy ,01 natural sciences ,Two-photon absorption ,Dissociation (chemistry) ,Ion ,symbols.namesake ,Engineering ,quant-ph ,Physics - Chemical Physics ,0103 physical sciences ,Physical and Theoretical Chemistry ,Chemical Physics (physics.chem-ph) ,Physics ,Quantum Physics ,Chemical Physics ,010304 chemical physics ,Degenerate energy levels ,Photodissociation ,Resonance ,0104 chemical sciences ,Physical Sciences ,Chemical Sciences ,Rydberg formula ,symbols ,physics.optics ,Atomic physics ,Quantum Physics (quant-ph) ,Physics - Optics ,Optics (physics.optics) - Abstract
We present a combined experimental and theoretical study on the photodissociation dynamics of ion-pair formation in O$_2$ following resonant two-photon absorption of a 9.3 eV femtosecond pulse, where the resulting O$^+$ ions are detected using 3-D momentum imaging. Ion-pair formation states of $^3\Sigma^-_g$ and $^3\Pi_g$ symmetry are accessed through predissociation of optically dark continuum Rydberg states converging to the B $^2\Sigma^-_g$ ionic state, which are resonantly populated via a mixture of both parallel-parallel and parallel-perpendicular two-photon transitions. This mixture is evident in the angular distribution of the dissociation relative to the light polarization, and varies with the kinetic energy release (KER) of the fragmenting ion-pair. The KER-dependent photoion angular distribution reveals the underlying two-photon absorption dynamics involved in the ion-pair production mechanism and indicates the existence of two nearly degenerate continuum resonances possessing different symmetries, which can both decay by coupling to ion-pair states of the same total symmetry through internal conversion., Comment: 8 pages, 5 figures, 1 table
- Published
- 2020
40. Selective bond scission in formic acid by low-energy electrons
- Author
-
Thomas N. Rescigno, C. William McCurdy, Brandon Griffin, Daniel Slaughter, Ali Belkacem, Ali Moradmand, Thorsten Weber, Joshua B. Williams, and C. S. Trevisan
- Subjects
History ,Formic acid ,Radical ,Electron ,Resonance (chemistry) ,Photochemistry ,Computer Science Applications ,Education ,Ion ,chemistry.chemical_compound ,chemistry ,Deuterium ,Isotopologue ,Bond cleavage - Abstract
We report recent results of mass-resolved anion fragment momentum imaging experiments to investigate dissociative electron attachment to formic acid, for incident energies between 5 eV and 9 eV. A remarkable site-selectivity is found for a resonance at 8.5 eV by comparing anion fragment yields for two deuterated isotopologues of formic acid. This results in an H− fragment from the O-H bond of the transient anion, with negligible contribution from C-H break. In contrast, a lower-energy resonance at 7.1 eV dissociates by C–H or O–H break to produce H− and the neutral radicals HOCO or HCOO.
- Published
- 2020
41. Determination of Interatomic Potentials of He2 , Ne2 , Ar2 , and H2 by Wave Function Imaging
- Author
-
Thorsten Weber, J. Voigtsberger, R. Dörner, Till Jahnke, M. Waitz, L. Ph. H. Schmidt, S. Zeller, Maksim Kunitski, A. Kalinin, Florian Trinter, Sebastian Eckart, Achim Czasch, and Markus Schöffler
- Subjects
Physics ,010304 chemical physics ,General Physics and Astronomy ,Interatomic potential ,Curvature ,01 natural sciences ,Diatomic molecule ,Schrödinger equation ,Momentum ,symbols.namesake ,Recoil ,0103 physical sciences ,symbols ,Atomic physics ,010306 general physics ,Wave function ,Energy (signal processing) - Abstract
We report on a direct method to measure the interatomic potential energy curve of diatomic systems. A cold target recoil ion momentum spectroscopy reaction microscope was used to measure the squares of the vibrational wave functions of H_{2}, He_{2}, Ne_{2}, and Ar_{2}. The Schrodinger equation relates the curvature of the wave function to the potential V(R) and therefore offers a simple but elegant way to extract the shape of the potential.
- Published
- 2018
42. Attosecond coherent control of oxygen dissociation by XUV-IR laser fields using three-dimensional momentum imaging
- Author
-
Niranjan Shivaram, Predrag Ranitovic, Dipanwita Ray, Daniel Slaughter, Thorsten Weber, Flavius Sturm, T. W. Wright, Ali Belkacem, I. Zalyubovskya, and Xiao-Min Tong
- Subjects
Physics ,General Physics ,Infrared ,Attosecond ,Electron ,01 natural sciences ,Mathematical Sciences ,010305 fluids & plasmas ,Ion ,Coherent control ,Ionization ,Excited state ,Physical Sciences ,Chemical Sciences ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Physics::Chemical Physics ,Atomic physics ,010306 general physics ,Ultrashort pulse - Abstract
Author(s): Ranitovic, P; Sturm, FP; Tong, XM; Wright, TW; Ray, D; Zalyubovskya, I; Shivaram, N; Belkacem, A; Slaughter, DS; Weber, T | Abstract: We have performed ultrafast three-dimensional ion momentum imaging spectroscopy on the dissociative single ionization of oxygen molecules using attosecond pulse trains with a broad energy spectrum of 5-30 eV. High-resolution momentum imaging allows clear identification of vibrational structures corresponding to the predissociation of highly excited cationic states. By adding a pump infrared field that is synchronized with and polarized orthogonally to the XUV pulse train, and an additional probe IR field, we demonstrate how the yield of O+ ions can be steered between different dissociation channels by coherently controlling the coupling between multiple O2+∗ electronic states on an attosecond time scale. Time-dependent calculations in a single active electron approximation allow a qualitative analysis of ion yields for two orientations of the molecular axis.
- Published
- 2018
43. Risk Factors for Early Dialysis Dependency in Autosomal Recessive Polycystic Kidney Disease
- Author
-
Kathrin Burgmaier, Kevin Kunzmann, Gema Ariceta, Carsten Bergmann, Anja Katrin Buescher, Mathias Burgmaier, Ismail Dursun, Ali Duzova, Loai Eid, Florian Erger, Markus Feldkoetter, Matthias Galiano, Michaela Geßner, Heike Goebel, Ibrahim Gokce, Dieter Haffner, Nakysa Hooman, Bernd Hoppe, Augustina Jankauskiene, Guenter Klaus, Jens König, Mieczyslaw Litwin, Laura Massella, Djalila Mekahli, Engin Melek, Sevgi Mir, Lars Pape, Larisa Prikhodina, Bruno Ranchin, Raphael Schild, Tomas Seeman, Lale Sever, Rukshana Shroff, Neveen A. Soliman, Stella Stabouli, Malgorzata Stanczyk, Yilmaz Tabel, Katarzyna Taranta-Janusz, Sara Testa, Julia Thumfart, Rezan Topaloglu, Lutz Thorsten Weber, Dorota Wicher, Elke Wühl, Simone Wygoda, Alev Yilmaz, Katarzyna Zachwieja, Ilona Zagozdzon, Klaus Zerres, Jörg Dötsch, Franz Schaefer, Max Christoph Liebau, Nadejda Ranguelov, Nathalie Godefroid, Laure Collard, Jacques Lombet, Julie Maquet, Gesa Schalk, Uwe Querfeld, Bodo B. Beck, Thomas Benzing, Reinhard Buettner, Franziska Grundmann, Christine Kurschat, Kerstin Benz, Anja Tzschoppe, Björn Buchholz, Rainer Buescher, Karsten Häffner, Martin Pohl, Oliver Gross, Jenny Krügel, Johanna Stock, Ludwig Patzer, Jun Oh, Wanja Bernhardt, Anke Doyon, Tobias Vinke, Anja Sander, Michael Henn, Ute Derichs, Rolf Beetz, Nikola Jeck, Bärbel Lange-Sperandio, Sabine Ponsel, Franziska Kusser, Barbara Uetz, Marcus Benz, Silke Schmidt, Christina Huppertz-Kessler, Birgitta Kranz, Andrea Titieni, Donald Wurm, Heinz E. Leichter, Martin Bald, Heiko Billing, Marwa M. Nabhan, Luis Enrique Lara, Fotios Papachristou, Francesco Emma, Rimante Cerkauskiene, Karolis Azukaitis, Anna Wasilewska, Irena Balasz-Chmielewska, Monika Miklaszewska, Marcin Tkaczyk, Przemyslaw Sikora, Marcin Zaniew, Ania Niemirska, Jolanta Antoniewicz, Justyna Lesiak, Alberto Caldas Afonso, Ana Teixeira, Gordana Milosevski-Lomic, Dusan Paripović, Amira Peco-Antic, Svetlana Papizh, Aysun Karabay Bayazit, Ali Anarat, Alper Soylu, Salih Kavukcu, Cengiz Candan, Salim Caliskan, Nur Canpolat, Sevinc Emre, Harika Alpay, Nurver Akinci, Secil Conkar, Hakan M. Poyrazoglu, Ruhan Dusunsel, Çukurova Üniversitesi, Burgmaier, Kathrin, Kunzmann, Kevin, Ariceta, Gema, Bergmann, Carsten, Buescher, Anja Katrin, Burgmaier, Mathias, Dursun, Ismail, Duzova, Ali, Eid, Loai, Erger, Florian, Feldkoetter, Markus, Galiano, Matthias, Gessner, Michaela, Goebel, Heike, Gokce, Ibrahim, Haffner, Dieter, Hooman, Nakysa, Hoppe, Bernd, Jankauskiene, Augustina, Klaus, Guenter, Koenig, Jens, Litwin, Mieczyslaw, Massella, Laura, Mekahli, Djalila, Melek, Engin, Mir, Sevgi, Pape, Lars, Prikhodina, Larisa, Ranchin, Bruno, Schild, Raphael, Seeman, Tomas, Sever, Late, Shroff, Rukshana, Soliman, Neveen A., Stabouli, Stella, Stanczyk, Malgorzata, Tabel, Yilmaz, Taranta-Janusz, Katarzyna, Testa, Sara, Thumfart, Julia, Topaloglu, Rezan, Weber, Lutz Thorsten, Wicher, Dorota, Wuehl, Elke, Wygoda, Simone, Yilmaz, Alev, Zachwieja, Katarzyna, Zagozdzon, Ilona, Zerres, Klaus, Doetsch, Joerg, Schaefer, Franz, and Liebau, Max Christoph
- Subjects
Male ,0301 basic medicine ,Time Factors ,medicine.medical_treatment ,ARPKD ,Medizin ,030232 urology & nephrology ,PROTEIN ,Oligohydramnios ,Pediatrics ,PKHD1 MUTATIONS ,0302 clinical medicine ,Pregnancy ,Risk Factors ,Prospective Studies ,ENCODES ,GENOTYPE-PHENOTYPE CORRELATIONS ,Obstetrics ,Hazard ratio ,Autosomal Recessive Polycystic Kidney Disease ,CLINICAL-EXPERIENCE ,Female ,Apgar score ,Life Sciences & Biomedicine ,renal replacement therapy ,medicine.medical_specialty ,GENETICS ,PKHD1 ,Risk Assessment ,Ultrasonography, Prenatal ,03 medical and health sciences ,Renal Dialysis ,medicine ,Humans ,Renal replacement therapy ,Dialysis ,Polycystic Kidney, Autosomal Recessive ,Retrospective Studies ,Science & Technology ,business.industry ,Infant, Newborn ,Infant ,Retrospective cohort study ,medicine.disease ,030104 developmental biology ,ciliopathy ,Pediatrics, Perinatology and Child Health ,business ,oligohydramnios ,Follow-Up Studies - Abstract
OBJECTIVE: To identify prenatal, perinatal, and postnatal risk factors for dialysis within the first year of life in children with autosomal recessive polycystic kidney disease (ARPKD) as a basis for parental counseling after prenatal and perinatal diagnosis. STUDY DESIGN: A dataset comprising 385 patients from the ARegPKD international registry study was analyzed for potential risk markers for dialysis during the first year of life. RESULTS: Thirty-six out of 385 children (9.4%) commenced dialysis in the first year of life. According to multivariable Cox regression analysis, the presence of oligohydramnios or anhydramnios, prenatal kidney enlargement, a low Apgar score, and the need for postnatal breathing support were independently associated with an increased hazard ratio for requiring dialysis within the first year of life. The increased risk associated with Apgar score and perinatal assisted breathing was time-dependent and vanished after 5 and 8 months of life, respectively. The predicted probabilities for early dialysis varied from 1.5% (95% CI, 0.5%-4.1%) for patients with ARPKD with no prenatal sonographic abnormalities to 32.3% (95% CI, 22.2%-44.5%) in cases of documented oligohydramnios or anhydramnios, renal cysts, and enlarged kidneys. CONCLUSIONS: This study, which identified risk factors associated with onset of dialysis in ARPKD in the first year of life, may be helpful in prenatal parental counseling in cases of suspected ARPKD. ispartof: JOURNAL OF PEDIATRICS vol:199 pages:22-+ ispartof: location:United States status: published
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- 2018
44. A near-field study on the transition from localized to propagating plasmons on 2D nano-wedges
- Author
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Stephan Irsen, Thomas Kiel, Thorsten Weber, Stefan Linden, and Kurt Busch
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Range (particle radiation) ,Materials science ,Condensed matter physics ,Electron energy loss spectroscopy ,FOS: Physical sciences ,Physics::Optics ,Near and far field ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Surface plasmon polariton ,Atomic and Molecular Physics, and Optics ,Computer Science::Emerging Technologies ,0103 physical sciences ,Scanning transmission electron microscopy ,Nano ,010306 general physics ,0210 nano-technology ,Plasmon ,Optics (physics.optics) ,Localized surface plasmon ,Physics - Optics - Abstract
In this manuscript we report on a near field study of two-dimensional plasmonic gold nano-triangles using electron energy loss spectroscopy in combination with scanning transmission electron microscopy, as well as discontinuous Galerkin time-domain computations. With increasing nano-triangle size, we observe a transition from localized surface plasmons on small nano-triangles to non-resonant propagating surface plasmon polaritons on large nano-triangles. Furthermore we demonstrate that nano-triangles with a groove cut can support localized as well as propagating plasmons in the same energy range.
- Published
- 2017
45. Unambiguous observation of F-atom core-hole localization in CF4 through body-frame photoelectron angular distributions
- Author
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J. Sartor, Cynthia S. Trevisan, Averell Gatton, Bishwanath Gaire, I. Ben-Itzhak, Markus Schöffler, R. Dörner, Sebastian Eckart, R. R. Lucchese, Joshua B. Williams, Allen Landers, Travis Severt, Ali Belkacem, Jonas Rist, Thorsten Weber, J. Neff, A. Moradmand, Thomas N. Rescigno, Philipp Stammer, Ben Berry, C. W. McCurdy, A. Menssen, and Till Jahnke
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Physics ,Body frame ,Core (optical fiber) ,Photon ,010304 chemical physics ,Ab initio quantum chemistry methods ,0103 physical sciences ,Atom ,Atomic physics ,Photoelectric effect ,010306 general physics ,01 natural sciences - Abstract
Citation: McCurdy, C. W., Rescigno, T. N., Trevisan, C. S., Lucchese, R. R., Gaire, B., Menssen, A., . . . Weber, T. (2017). Unambiguous observation of F-atom core-hole localization in CF4 through body-frame photoelectron angular distributions. Physical Review A, 95(1). doi:10.1103/PhysRevA.95.011401
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- 2017
46. Erratum: Electron Localization in Dissociating H2+ by Retroaction of a Photoelectron onto Its Source [Phys. Rev. Lett. 116 , 043001 (2016)]
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Gregor Schiwietz, Jonas Rist, Markus Schöffler, L. Ph. H. Schmidt, Felix Sturm, T. Jahnke, J. Voigtsberger, M. Weller, M. Waitz, F. Wiegandt, S. Zeller, G. Kastirke, D. Aslitürk, Thorsten Weber, H. K. Gill, R. Dörner, N. Wechselberger, Joshua B. Williams, D. Metz, T. Bauer, C. Goihl, and Florian Trinter
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Physics ,General Physics and Astronomy ,Atomic physics ,Electron localization function - Published
- 2016
47. Bond-rearrangement and ionization mechanisms in the photo-double-ionization of simple hydrocarbons (C2H4,C2H3F, and1,1−C2H2F2) near and above threshold
- Author
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I. Ben-Itzhak, S. Zeller, C. Janke, D. Reedy, Ali Belkacem, Thorsten Weber, A. L. Landers, J. Neff, Jyoti Rajput, Averell Gatton, Bishwanath Gaire, and F. Wiegandt
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Physics ,010304 chemical physics ,Double ionization ,Electron ,01 natural sciences ,Molecular physics ,Dissociation (chemistry) ,Ion ,Electronegativity ,Recoil ,Ionization ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Molecule ,Physics::Atomic Physics ,Physics::Chemical Physics ,010306 general physics - Abstract
We investigate bond-rearrangement driven by photo-double-ionization (PDI) near and above the double-ionization threshold in a sequence of carbon-carbon double-bonded hydrocarbon molecules: ethylene, fluoroethylene, and 1,1-difluoroethylene. We employ the kinematically complete cold target recoil ion momentum spectroscopy method to resolve all photo-double-ionization events leading to two-ion fragments. We observe changes in the branching ratios of different dissociative ionization channels depending on the presence of no, one, or two fluorine atoms. The role of the fluorine atom in the bond-rearrangement channels is intriguing, as evident by the reordering of the threshold energies of the PDI in the fluorinated molecules. These effects offer a compelling argument that the electronegativity of the fluorine (or the polarity of the molecule) strongly influences the potential energy surfaces of the molecules and drives bond rearrangement during the dissociation process. The energy sharing and the relative angle between the three-dimensional momentum vectors of the two electrons enable us to distinguish between knockout and other ionization mechanisms of the PDI processes.
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- 2016
48. Electron Localization in DissociatingH2+by Retroaction of a Photoelectron onto Its Source
- Author
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Markus Schöffler, H. K. Gill, F. Wiegandt, Thorsten Weber, Joshua B. Williams, C. Goihl, D. Metz, Till Jahnke, N. Wechselberger, Felix Sturm, T. Bauer, J. Voigtsberger, Florian Trinter, M. Weller, G. Kastirke, Gregor Schiwietz, Jonas Rist, S. Zeller, M. Waitz, D. Aslitürk, R. Dörner, and L. Ph. H. Schmidt
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Physics ,Photon ,010308 nuclear & particles physics ,General Physics and Astronomy ,Electron ,01 natural sciences ,Dissociation (chemistry) ,Electron localization function ,Ionization ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,Symmetry breaking ,Electric potential ,Atomic physics ,010306 general physics ,Ground state - Abstract
We investigate the dissociation of H_{2}^{+} into a proton and a H^{0} after single ionization with photons of an energy close to the threshold. We find that the p^{+} and the H^{0} do not emerge symmetrically in the case of the H_{2}^{+} dissociating along the 1sσ_{g} ground state. Instead, a preference for the ejection of the p^{+} in the direction of the escaping photoelectron can be observed. This symmetry breaking is strongest for very small electron energies. Our experiment is consistent with a recent prediction by Serov and Kheifets [Phys. Rev. A 89, 031402 (2014)]. In their model, which treats the photoelectron classically, the symmetry breaking is induced by the retroaction of the long-range Coulomb potential onto the dissociating H_{2}^{+}.
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- 2016
49. Two-Particle Interference of Electron Pairs on a Molecular Level
- Author
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Fernando Martín, C. Schober, Julian Lower, Joshua B. Williams, D. Metz, Felipe Morales, K. Mertens, Shungo Miyabe, L. Ph. H. Schmidt, C. W. McCurdy, Till Jahnke, Reinhard Dörner, Markus Schöffler, S. Klumpp, Jens Viefhaus, M. Waitz, Michael Martins, Thorsten Weber, M. Pitzer, M. Keiling, Horst Schmidt-Böcking, Thomas N. Rescigno, and UAM. Departamento de Química
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General Physics ,Photon ,Atomic Physics (physics.atom-ph) ,FOS: Physical sciences ,General Physics and Astronomy ,Electron ,physics.atm-clus ,Interference (wave propagation) ,01 natural sciences ,physics.atom-ph ,Mathematical Sciences ,Physics - Atomic Physics ,Engineering ,quant-ph ,Molecular levels ,Ionization ,0103 physical sciences ,Emitted electron ,ddc:550 ,Angular emission ,Physics - Atomic and Molecular Clusters ,010306 general physics ,Physics ,Electron pair ,Quantum Physics ,010308 nuclear & particles physics ,Química ,Physical Sciences ,Quasiparticle ,Particle ,Atomic physics ,Atomic and Molecular Clusters (physics.atm-clus) ,Quantum Physics (quant-ph) ,Sign (mathematics) - Abstract
We investigate the photodouble ionization of H2 molecules with 400 eV photons. We find that the emitted electrons do not show any sign of two-center interference fringes in their angular emission distributions if considered separately. In contrast, the quasiparticle consisting of both electrons (i.e., the "dielectron") does. The work highlights the fact that nonlocal effects are embedded everywhere in nature where many-particle processes are involved, This work was funded by the Deutsche Forschungsgemeinschaft (DFG), the BMBF, the European COST Action Grant No. XLIC CM1204, the European Research Council Advanced XCHEM Grant No. 290853, and the MINECO Project Grant No. FIS2013-42002-R. J. L. thanks the DFG for support. We are grateful to the staff of PETRA III for excellent support during the beam time. Raw data are archived at the Goethe-University Frankfurt am Main and are available on request
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- 2016
50. Publisher Correction: Imaging the square of the correlated two-electron wave function of a hydrogen molecule
- Author
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D. Metz, F. Martín, Joshua B. Williams, M. Pitzer, Julian Lower, Markus Schöffler, Thorsten Weber, C. Schober, Vladislav V. Serov, Anatoli Kheifets, L. Ph. H. Schmidt, Luca Argenti, K. Mertens, U. Lenz, S. Klumpp, Jens Viefhaus, Till Jahnke, Florian Trinter, M. Waitz, Roger Y. Bello, R. Dörner, Alicia Palacios, M. Keiling, and Michael Martins
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Physics::General Physics ,Science ,Physics::Medical Physics ,General Physics and Astronomy ,02 engineering and technology ,General Biochemistry, Genetics and Molecular Biology ,Square (algebra) ,03 medical and health sciences ,Projection (mathematics) ,Quantum mechanics ,ddc:530 ,Wave function ,lcsh:Science ,030304 developmental biology ,Physics ,0303 health sciences ,Multidisciplinary ,Electronic correlation ,Hydrogen molecule ,Zero (complex analysis) ,General Chemistry ,021001 nanoscience & nanotechnology ,Publisher Correction ,Uncorrelated ,Section (category theory) ,lcsh:Q ,ddc:500 ,0210 nano-technology - Abstract
Nature Communications 9(1), 2259 (2018). doi:10.1038/s41467-018-04740-5, The toolbox for imaging molecules is well-equipped today. Some techniques visualize the geometrical structure, others the electron density or electron orbitals. Molecules are many-body systems for which the correlation between the constituents is decisive and the spatial and the momentum distribution of one electron depends on those of the other electrons and the nuclei. Such correlations have escaped direct observation by imaging techniques so far. Here, we implement an imaging scheme which visualizes correlations between electrons by coincident detection of the reaction fragments after high energy photofragmentation. With this technique, we examine the H2 two-electron wave function in which electron–electron correlation beyond the mean-field level is prominent. We visualize the dependence of the wave function on the internuclear distance. High energy photoelectrons are shown to be a powerful tool for molecular imaging. Our study paves the way for future time resolved correlation imaging at FELs and laser based X-ray sources., Published by Nature Publishing Group UK, [London]
- Published
- 2018
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