H. Olof Jönsson
A5048508271- Advanced X-ray Imaging Techniques
- Enzyme Structure and Function
- Advanced Electron Microscopy Techniques and Applications
- Laser-Plasma Interactions and Diagnostics
- Laser-Matter Interactions and Applications
- Particle Accelerators and Free-Electron Lasers
- X-ray Spectroscopy and Fluorescence Analysis
- Laser-induced spectroscopy and plasma
- Atmospheric aerosols and clouds
- Protein Structure and Dynamics
- Intensive Care Unit Cognitive Disorders
- Mass Spectrometry Techniques and Applications
- Remote Sensing and LiDAR Applications
- Photosynthetic Processes and Mechanisms
- Cardiac Arrest and Resuscitation
- Ion-surface interactions and analysis
- Atmospheric chemistry and aerosols
- Visual perception and processing mechanisms
- Lipid Membrane Structure and Behavior
- Remote Sensing in Agriculture
- Laser Material Processing Techniques
- High-pressure geophysics and materials
- Neurobiology and Insect Physiology Research
- Animal Behavior and Reproduction
- Glass properties and applications
KTH Royal Institute of Technology
2019-2024
AlbaNova
2020-2022
Uppsala University
2011-2019
Swedish Institute of Space Physics
2016
We present a proof-of-concept three-dimensional reconstruction of the giant mimivirus particle from experimentally measured diffraction patterns an x-ray free-electron laser. Three-dimensional imaging requires assembly many two-dimensional into internally consistent Fourier volume. Since each is randomly oriented when exposed to pulse, relative orientations have be retrieved data alone. achieve this with modified version expand, maximize and compress algorithm validate our result using new...
Proteins that contain metal cofactors are expected to be highly radiation sensitive since the degree of X-ray absorption correlates with presence high-atomic-number elements and energy. To explore effects local damage in serial femtosecond crystallography (SFX), Clostridium ferredoxin was used as a model system. The protein contains two [4Fe-4S] clusters serve probes for radiation-induced electronic structural changes. High-dose room-temperature SFX datasets were collected at Linac Coherent...
Unravelling the interaction of biological macromolecules with ligands and substrates at high spatial temporal resolution remains a major challenge in structural biology. The development serial crystallography methods X-ray free-electron lasers subsequently synchrotron light sources allows new approaches to tackle this challenge. Here, polyimide tape drive designed for mix-and-diffuse experiments is reported. structure lysozyme bound by competitive inhibitor chitotriose was determined using...
We describe femtosecond X-ray diffraction data sets of viruses and nanoparticles collected at the Linac Coherent Light Source.The establish first large benchmark for coherent methods freely available to public, bolster development algorithms that are essential developing this novel approach as a useful imaging technique.Applications 2D reconstructions, orientation classification finally 3D by assembling patterns into volume.
Significance X-ray Free-Electron Lasers have opened the door to a new era in structural biology, enabling imaging of biomolecules and dynamics that were impossible access with conventional methods. A vast majority experiments, including Serial Femtosecond Crystallography, use liquid jet deliver sample into interaction region. We observed changes carrying water during exposure, showing how it transforms from phase plasma. This ultrafast transition provides evidence any biological structure...
In structural determination of crystalline proteins using intense femtosecond X-ray lasers, damage processes lead to loss coherence during the exposure. We use a nonthermal description for dynamics calculate ultrafast ionization and subsequent atomic displacement. These effects degrade Bragg diffraction on time scales gate imaging. This process is intensity resolution dependent. At high intensities signal gated by affecting low information first. lower intensities, displacement dominates...
Understanding how ice nucleates and grows into larger crystals is of crucial importance for many research fields. The purpose this study was to shed light on the phase structure once a nucleus formed inside metastable water droplet. Wide-angle X-ray scattering (WAXS) performed micron-sized droplets evaporatively cooled temperatures where homogeneous nucleation occurs. We found that our weak hits more cubic compared strong are completely hexagonal. Due efficient heat removal caused by...
Results of coherent diffractive imaging experiments performed with soft X-rays (1-2 keV) at the Linac Coherent Light Source are presented. Both organic and inorganic nano-sized objects were injected into XFEL beam as an aerosol focused aerodynamic lens. The high intensity femtosecond duration X-ray pulses produced by allow structural information to be recorded diffraction before particle is destroyed. Images formed using iterative methods phase single shot patterns. Strategies for improving...
Serial femtosecond X-ray crystallography of protein nanocrystals using ultrashort and intense pulses from an free-electron laser has proved to be a successful method for structural determination. However, due significant variations in diffraction pattern quality pulse only fraction the collected frames can used. Experimentally, temporal profile is not known vary with every shot. This simulation study describes how shape affects damage dynamics, which ultimately biological interpretation...
Single particle imaging (SPI) using X-ray pulses has become increasingly attainable with the advent of high-intensity free electron lasers. Eliminating need for crystallized samples enables structural studies molecules previously inaccessible by conventional crystallography. While this emerging technique already demonstrates substantial promise, some obstacles to be overcome before SPI can reach its full potential. One such problem is determining spatial orientation sample at time...
Serial crystallography of membrane proteins often employs high-viscosity injectors (HVIs) to deliver micrometre-sized crystals the X-ray beam. Typically, carrier medium is a lipidic cubic phase (LCP) media, which can also be used nucleate and grow crystals. However, despite fact that LCP widely with HVIs, potential impact injection process on structure has not been reported hence yet well understood. The self-assembled affected by pressure, dehydration temperature changes, all occur during...
Background Nursing procedures that are routinely performed in the intensive care unit ( ICU ) assumed to have minimal side effects. However, these may sometimes cause physiological changes negatively affect patient. We hypothesized associated with routine nursing common. Methods A clinical observational study of 16 critically ill patients a nine‐bed mixed university hospital . All were observed, and data collected subsequently analyzed. Minor defined as respiratory or circulatory variables,...
The evolution of bismuth crystal structure upon excitation its A1g phonon has been intensely studied with short pulse optical lasers. Here we present the first-time observation a hard x-ray induced ultrafast phase transition in single at high intensities (~1014 W/cm2). lattice was followed using recently demonstrated single-shot probing setup. time (111) Bragg peak intensity showed strong dependence on fluence. After exposure to sufficiently intense pulse, dropped zero within 300 fs, i.e....
White noise techniques have been used widely to investigate sensory systems in both vertebrates and invertebrates. stimuli are powerful their ability rapidly generate data that help the experimenter decipher spatio-temporal dynamics of neural behavioral responses. One type white stimuli, maximal length shift register sequences (m-sequences), recently become particularly popular for extracting response kernels insect motion vision. We here use such m-sequences extract impulse responses figure...
Serial femtosecond crystallography is an emerging and promising method for determining protein structures, making use of the ultrafast bright X-ray pulses from free-electron lasers. The upcoming laser sources will produce well above 1000 per second pose a new challenge: how to quickly determine successful crystal hits avoid high-rate data deluge. Proposed here hit-finding scheme based on detecting photons plasma emission after sample has been intercepted by laser. Plasma spectra are...
Abstract Single Particle Imaging (SPI) with intense coherent X-ray pulses from free-electron lasers (XFELs) has the potential to produce molecular structures without need for crystallization or freezing. Here we present a dataset of 285,944 diffraction patterns aerosolized Coliphage PR772 virus particles injected into femtosecond Linac Coherent Light Source (LCLS). Additional exposures background information are also deposited. The data were collected at Atomic, Molecular and Optical Science...
Water and ice are routinely studied with X-rays to reveal their diverse structures anomalous properties. We employ a hybrid collisional-radiative/molecular-dynamics method explore how femtosecond X-ray pulses interact hexagonal ice. find that makes phase transition into crystalline plasma where its initial structure is maintained up tens of femtoseconds. The ultrafast melting process occurs anisotropically, different geometric configurations the melt on time scales. transient state...
The evolution of the bismuth crystal structure upon excitation its A$_{1g}$ phonon has been intensely studied with short pulse optical lasers. Here we present first-time observation a hard x-ray induced ultrafast phase transition in single crystal, at high intensities (~$10^{14}$ W/cm$^2$). lattice was followed using recently demonstrated single-shot probing setup. time (111) Bragg peak intensity showed strong dependence on fluence. After exposure to sufficiently intense pulse, dropped zero...