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Protein crystallography is an established method to study the atomic structures of macromolecules and their complexes. A prerequisite for successful structure determination is diffraction‐quality crystals, which may require extensive optimization of both the protein and the conditions, and hence projects can stretch over an extended period, with multiple users being involved. The workflow from crystallization and crystal treatment to deposition and publication is well defined, and therefore an electronic laboratory information management system (LIMS) is well suited to management of the data. Completion of the project requires key information on all the steps being available and this information should also be made available according to the FAIR principles. As crystallized samples are typically shipped between facilities, a key feature to be captured in the LIMS is the exchange of metadata between the crystallization facility of the home laboratory and, for example, synchrotron facilities. On completion, structures are deposited in the Protein Data Bank (PDB) and the LIMS can include the PDB code in its database, completing the chain of custody from crystallization to structure deposition and publication. A LIMS designed for macromolecular crystallography, IceBear, is available as a standalone installation and as a hosted service, and the implementation of key features for the capture of metadata in IceBear is discussed as an example. [ABSTRACT FROM AUTHOR]

Coherent scatter echoes from disintegrating meteors and from the unstable ionospheric E‐region can overlap considerably between 90 and 110 km altitudes. As the physical origin of plasma irregularities produced by meteor trails differs starkly from that of E‐region auroral irregularities, this has consequences for winds as well as electrodynamic studies, thereby introducing a need to distinguish between the two types of echoes. To that goal, we have developed a novel separation algorithm to automatically sort through arbitrarily large data sets in the region of overlap. This proves very useful when the 3D location of echoes is available. The algorithm uses a definition of crowding, or clustering, in both time and space and has been developed and tested with a comprehensive data set obtained from the recently built Canadian icebear 3D radar. We discuss the characteristics belonging to the two classes of echoes, and present statistical results about the location of each type of echo as a function of conditions. Our proposed algorithm can be applied to any coherent scatter echo data with high resolution 3D location information. Plain Language Summary: Radars measure turbulence in space plasma by bouncing a signal off of sharp plasma density gradients in the ionosphere. For decades, such coherent radars have been useful tools to investigate the ionosphere. However, when probing E‐region plasma, a coherent radar will pick up plasma produced by meteors as they enter Earth's atmosphere. We have developed an automatic algorithm to separate meteor trail echoes, as they are called, from space plasma measurements. We demonstrate the efficiency of this algorithm on the icebear 3D data set, which has an unprecedented resolution, and offers accurate 3D location data for space plasma turbulence. Key Points: Using new data from icebear 3D, we find that ionospheric turbulence overlap with meteor trail echoes between 90 and 110 km altitudeThe starkly different patterns of clustering in time and space of high latitude ionospheric turbulence and meteoric echoes are used to distinguish the echo typesThe spatial and temporal separation between observed meteor trail echoes is normally several orders of magnitude above that of ionospheric turbulence echoes at high latitudes [ABSTRACT FROM AUTHOR]

The Ionospheric Continuous‐wave E region Bistatic Experimental Auroral Radar (ICEBEAR) has been reconfigured using a phase error minimization and stochastic antenna location perturbation technique. The resulting 45‐baseline sparse non‐uniform coplanar T‐shaped array, ICEBEAR‐3D, is used for aperture synthesis radar imaging of low elevation targets. The reconfigured receiver antenna array now has a field of view ±45° azimuth and 0°–45° elevation at 0.1° angular resolution. Within this field of view no aliasing occurs. Radar targets are imaged using the Suppressed Spherical Wave Harmonic Transform (Suppressed‐SWHT) technique. This imaging method uses precalculated constant coefficient matrices to solve the integral transform from visibility to brightness through direct matrix multiplication. The method then suppresses image artefacts (dirty beam) due to undersampling by combining brightness maps of differing harmonic order. Measuring elevation angles of targets at low elevations with radar interferometers has been a long standing problem. ICEBEAR‐3D elucidates the underlying misinterpretations of the conventional geometry for vertical interferometry especially for low elevation angles. The proper phase reference vertical interferometry geometry is given which allows radar interferometers to unambiguously measure elevation angles from zenith to horizon without special calibration. The receiver antenna array reconfiguration, Suppressed‐SWHT imaging technique, and proper geometry for vertical interferometry are validated by showing agreement of the meteor trail altitude distribution with numerous data sets from other radars. Key Points: Ionospheric Continuous‐wave E region Bistatic Experimental Auroral Radar receiver antenna array reconfiguration design based on a phase error minimization techniqueAperture synthesis imaging using the Suppressed Spherical Wave Harmonic Transform (Suppressed‐SHWT)Application of the proper geometry for vertical interferometry resolves low elevation angles unambiguously [ABSTRACT FROM AUTHOR]

For the first time, near infrared (NIR) auroral emissions measured from space have been compared with E‐region coherent scatter. The E‐region coherent scatter observations were obtained by the 49.5 MHz Ionospheric Continuous‐wave E‐region Bistatic Experimental Auroral Radar (ICEBEAR) in western Canada. NIR emissions integrated over 650–1,100 nm wavelengths were obtained from the Fast Auroral Imager instrument onboard e‐POP on CASSIOPE (now Swarm‐E) with a 1 s temporal resolution (same as ICEBEAR), with the instrument slewed to the center of the ICEBEAR field‐of‐view. The coherent echoes and the NIR emissions are expected to originate below 120 km altitude. The radar spectra indicated that the turbulence was very weak. The location of all coherent echoes corresponded to NIR emission brightness values of more than 250 kR (kilo‐Rayleighs) and less than 1,250 kR. When the emissions were very bright, the electric fields were seemingly too weak to produce plasma instabilities, explaining why no radar echoes were detected. By contrast, even if the electric field happened to be relatively strong in dark regions, the background plasma densities were too small to generate detectable coherent scatter radar echoes. The Doppler shifts of the coherent scatter spectra were clustered around 465 and ± 250 m/s. These magnitudes did not agree with the quiet 350 m/s ion‐acoustic speed expected from the weaker electric fields that should have prevailed under weak turbulence situations. The unexpected Doppler shifts were potentially due to either unexpected strong electric fields and altitude variations, or ambient km‐size density gradients at 110 km. Plain Language Summary: The aurora occurs when the atmosphere stops energetic charged particles. It is a signature of atmospheric ionization. Emissions in the near infrared (NIR) are known to correspond to electrons stopped near 110 km altitude. When the ionospheric electric field exceeds approximately 20 mV/m the relative drift between ions and electrons below 120 km becomes strong enough that the plasma becomes unstable to a mechanism known as the "Farley‐Buneman instability mechanism." Radars can detect structures generated by this instability. For the results presented here, the 49.5 MHz Ionospheric Continuous‐wave E‐region Bistatic Experimental Auroral Radar (ICEBEAR) radar detected 3 m structures generated by the instability. The Fast Auroral Imager onboard the Swarm‐E satellite provided NIR observations coming from approximately 110 km altitude simultaneously with overlapping radar observations. The results revealed that radar echoes were seen in the region of NIR emissions only if the emissions were between 250 and 1,250 kR brightness, indicating that under very bright emissions, the auroral electric field was too weak to trigger instability. When the emissions were too faint, the plasma density was too small to warrant detection of structures by ICEBEAR even if irregularities were to be present. The radar data also indicated that turbulence was weak even though the observed Doppler shifts were not what is expected from such situations. Key Points: First time comparisons between Auroral Near Infrared Emissions and E‐region coherent scatter dataCoherent E‐region echoes only occur when integrated auroral brightness at 650–1,100 nm wavelengths is between 250 and 1,250 kRayleighsFor the available data, a vast majority of the E‐region coherent echoes are associated with weak turbulence situations [ABSTRACT FROM AUTHOR]

The web‐based IceBear software is a versatile tool to monitor the results of crystallization experiments and is designed to facilitate supervisor and student communications. It also records and tracks all relevant information from crystallization setup to PDB deposition in protein crystallography projects. Fully automated data collection is now possible at several synchrotrons, which means that the number of samples tested at the synchrotron is currently increasing rapidly. Therefore, the protein crystallography research communities at the University of Oulu, Weizmann Institute of Science and Diamond Light Source have joined forces to automate the uploading of sample metadata to the synchrotron. In IceBear, each crystal selected for data collection is given a unique sample name and a crystal page is generated. Subsequently, the metadata required for data collection are uploaded directly to the ISPyB synchrotron database by a shipment module, and for each sample a link to the relevant ISPyB page is stored. IceBear allows notes to be made for each sample during cryocooling treatment and during data collection, as well as in later steps of the structure determination. Protocols are also available to aid the recycling of pins, pucks and dewars when the dewar returns from the synchrotron. The IceBear database is organized around projects, and project members can easily access the crystallization and diffraction metadata for each sample, as well as any additional information that has been provided via the notes. The crystal page for each sample connects the crystallization, diffraction and structural information by providing links to the IceBear drop‐viewer page and to the ISPyB data‐collection page, as well as to the structure deposited in the Protein Data Bank. [ABSTRACT FROM AUTHOR]