| 1. |
- Zettergren, Henning, et al.
(författare)
-
Roadmap on dynamics of molecules and clusters in the gas phase
- 2021
-
Ingår i: European Physical Journal D. - : Springer Science and Business Media LLC. - 1434-6060 .- 1434-6079. ; 75:5
-
Tidskriftsartikel (refereegranskat)abstract
- This roadmap article highlights recent advances, challenges and future prospects in studies of the dynamics of molecules and clusters in the gas phase. It comprises nineteen contributions by scientists with leading expertise in complementary experimental and theoretical techniques to probe the dynamics on timescales spanning twenty order of magnitudes, from attoseconds to minutes and beyond, and for systems ranging in complexity from the smallest (diatomic) molecules to clusters and nanoparticles. Combining some of these techniques opens up new avenues to unravel hitherto unexplored reaction pathways and mechanisms, and to establish their significance in, e.g. radiotherapy and radiation damage on the nanoscale, astrophysics, astrochemistry and atmospheric science.
|
|
| 2. |
- Curbis, F, et al.
(författare)
-
HIGHLIGHTS FROM THE CONCEPTUAL DESIGN REPORT OF THE SOFT X-RAY LASER AT MAX IV
- 2021
-
Ingår i: Proceedings of IPAC2021.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The SXL (Soft X-ray Laser) project developed a conceptual design for a soft X-ray Free Electron Laser (FEL) in the 1-5 nm wavelength range, driven by the existing MAX IV 3 GeV linac. In this contribution we will focus on the FEL operation modes developed for the first phase of the project based on two different linac modes. The design work was supported by the Knut and Alice Wallenberg foundation and by several Swedish universities and organizations (
|
|
| 3. |
|
|
| 4. |
- Garg, D., et al.
(författare)
-
Fragmentation Dynamics of Fluorene Explored Using Ultrafast XUV-Vis Pump-Probe Spectroscopy
- 2022
-
Ingår i: Frontiers in Physics. - : Frontiers Media SA. - 2296-424X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- We report on the use of extreme ultraviolet (XUV, 30.3 nm) radiation from the Free-electron LASer in Hamburg (FLASH) and visible (Vis, 405 nm) photons from an optical laser to investigate the relaxation and fragmentation dynamics of fluorene ions. The ultrashort laser pulses allow to resolve the molecular processes occurring on the femtosecond timescales. Fluorene is a prototypical small polycyclic aromatic hydrocarbon (PAH). Through their infrared emission signature, PAHs have been shown to be ubiquitous in the universe, and they are assumed to play an important role in the chemistry of the interstellar medium. Our experiments track the ionization and dissociative ionization products of fluorene through time-of-flight mass spectrometry and velocity-map imaging. Multiple processes involved in the formation of each of the fragment ions are disentangled through analysis of the ion images. The relaxation lifetimes of the excited fluorene monocation and dication obtained through the fragment formation channels are reported to be in the range of a few tens of femtoseconds to a few picoseconds.
|
|
| 5. |
- Gryzlova, E. V., et al.
(författare)
-
Influence of an atomic resonance on the coherent control of the photoionization process
- 2022
-
Ingår i: Physical Review Research. - 2643-1564. ; 4:3
-
Tidskriftsartikel (refereegranskat)abstract
- In coherent control schemes, pathways connecting an initial and a final state can be independently controlled by manipulating the complex amplitudes of their transition matrix elements. For paths characterized by the absorption of multiple photons, these quantities depend on the magnitude and phase between the intermediate steps, and are expected to be strongly affected by the presence of resonances. We investigate the coherent control of the photoemission process in neon using a phase-controlled two-color extreme ultraviolet pulse with frequency in proximity of an excited energy state. Using helium as a reference, we show that the presence of such a resonance in neon modifies the amplitude and phase of the asymmetric emission of photoelectrons. Theoretical simulations based on perturbation theory are in fair agreement with the experimental observations.
|
|
| 6. |
- Lee, J. W. L., et al.
(författare)
-
The kinetic energy of PAH dication and trication dissociation determined by recoil-frame covariance map imaging
- 2022
-
Ingår i: Physical Chemistry, Chemical Physics - PCCP. - : Royal Society of Chemistry (RSC). - 1463-9076 .- 1463-9084. ; 24:38, s. 23096-23105
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated the dissociation of dications and trications of three polycyclic aromatic hydrocarbons (PAHs), fluorene, phenanthrene, and pyrene. PAHs are a family of molecules ubiquitous in space and involved in much of the chemistry of the interstellar medium. In our experiments, ions are formed by interaction with 30.3 nm extreme ultraviolet (XUV) photons, and their velocity map images are recorded using a PImMS2 multi-mass imaging sensor. Application of recoil-frame covariance analysis allows the total kinetic energy release (TKER) associated with multiple fragmentation channels to be determined to high precision, ranging 1.94-2.60 eV and 2.95-5.29 eV for the dications and trications, respectively. Experimental measurements are supported by Born-Oppenheimer molecular dynamics (BOMD) simulations.
|
|
| 7. |
- Lee, J. W.L., et al.
(författare)
-
Time-resolved relaxation and fragmentation of polycyclic aromatic hydrocarbons investigated in the ultrafast XUV-IR regime
- 2021
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 12:1
-
Tidskriftsartikel (refereegranskat)abstract
- Polycyclic aromatic hydrocarbons (PAHs) play an important role in interstellar chemistry and are subject to high energy photons that can induce excitation, ionization, and fragmentation. Previous studies have demonstrated electronic relaxation of parent PAH monocations over 10-100 femtoseconds as a result of beyond-Born-Oppenheimer coupling between the electronic and nuclear dynamics. Here, we investigate three PAH molecules: fluorene, phenanthrene, and pyrene, using ultrafast XUV and IR laser pulses. Simultaneous measurements of the ion yields, ion momenta, and electron momenta as a function of laser pulse delay allow a detailed insight into the various molecular processes. We report relaxation times for the electronically excited PAH*, PAH(+*) and PAH(2+*) states, and show the time-dependent conversion between fragmentation pathways. Additionally, using recoil-frame covariance analysis between ion images, we demonstrate that the dissociation of the PAH(2+) ions favors reaction pathways involving two-body breakup and/or loss of neutral fragments totaling an even number of carbon atoms. Polycyclic aromatic hydrocarbons play an important role in interstellar chemistry, where interaction with high energy photons can induce ionization and fragmentation reactions. Here the authors, with XUV-IR pump-probe experiments, investigate the ultrafast photoinduced dynamics of fluorene, phenanthrene and pyrene, providing insight into their preferred reaction channels.
|
|
| 8. |
- Manschwetus, B., et al.
(författare)
-
Ultrafast ionization and fragmentation dynamics of polycyclic atomatic hydro-carbons by XUV radiation
- 2020
-
Ingår i: Free Electron Laser. - : IOP Publishing. - 1742-6588. ; 1412
-
Konferensbidrag (refereegranskat)abstract
- In the interstellar medium polycyclic aromatic hydrocarbon molecules (PAH) are exposed to strong ionizing radation leading to complex organic photochemistry. We investigated these ultrafast fragmentation reac-tions after ionization of the PAHs phenanthrene, fluorene and pyrene at a wavelength of 30.3 nm using pump probe spectroscopy at a free electron laser. We observe double ionization and afterwards hydrogen abstraction and acetylene loss with characteristic time scales for the reaction processes below one hundred femtoseconds.
|
|
| 9. |
- Sodergren, S. C., et al.
(författare)
-
International Validation of the EORTC QLQ-ANL27, a Field Study to Test the Anal Cancer–Specific Health-Related Quality of Life Questionnaire
- 2023
-
Ingår i: International Journal of Radiation Oncology Biology Physics. - : Elsevier BV. - 0360-3016. ; 115:5, s. 1155 - 1164
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: The European Organisation for Research and Treatment of Cancer (EORTC) health-related quality of life questionnaire for anal cancer (QLQ-ANL27) supplements the EORTC cancer generic measure (QLQ-C30) to measure concerns specific to people with anal cancer treated with chemoradiotherapy. This study tested the psychometric properties and acceptability of the QLQ-ANL27. Methods and Materials: People with anal cancer were recruited from 15 countries to complete the QLQ-C30 and QLQ-ANL27 and provide feedback on the QLQ-ANL27. Item responses, scale structure (multitrait scaling, factor analysis), reliability (internal consistency and reproducibility) and sensitivity (known group comparisons and responsiveness to change) of the QLQ-ANL27 were evaluated. Results: Data from 382 people were included in the analyses. The EORTC QLQ-ANL27 was acceptable, comprehensive, and easy to complete, taking an average 8 minutes to complete. Psychometric analyses supported the EORTC QLQ-ANL27 items and reliability (Cronbach's α ranging from 0.71-0.93 and test-retest coefficients above 0.7) and validity of the scales (particularly nonstoma bowel symptoms and pain/discomfort). Most scales distinguished people according to treatment phase and performance status. Bowel (nonstoma), pain/discomfort, and vaginal symptoms were sensitive to deteriorations over time. The stoma-related scales remained untested because of low numbers of people with a stoma. Revisions to the scoring and question ordering of the sexual items were proposed. Conclusions: The QLQ-ANL27 has good psychometric properties and is available in 16 languages for people treated with chemoradiotherapy for anal cancer. It is used in clinical trials and has a potential role in clinical practice.
|
|
| 10. |
- Trkulja, C. L., et al.
(författare)
-
Rational antibody design for undruggable targets using kinetically controlled biomolecular probes
- 2021
-
Ingår i: Science Advances. - : American Association for the Advancement of Science (AAAS). - 2375-2548. ; 7:16
-
Tidskriftsartikel (refereegranskat)abstract
- Several important drug targets, e.g., ion channels and G protein-coupled receptors, are extremely difficult to approach with current antibody technologies. To address these targets classes, we explored kinetically controlled proteases as structural dynamics-sensitive druggability probes in native-state and disease-relevant proteins. By using low-Reynolds number flows, such that a single or a few protease incisions are made, we could identify antibody binding sites (epitopes) that were translated into short-sequence antigens for antibody production. We obtained molecular-level information of the epitope-paratope region and could produce high-affinity antibodies with programmed pharmacological function against difficult-to-drug targets. We demonstrate the first stimulus-selective monoclonal antibodies targeting the transient receptor potential vanilloid 1 (TRPV1) channel, a clinically validated pain target widely considered undruggable with antibodies, and apoptosis-inducing antibodies selectively mediating cytotoxicity in KRAS-mutated cells. It is our hope that this platform will widen the scope of antibody therapeutics for the benefit of patients.
|
|
