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Shell galaxies make a class of tidally distorted galaxies, characterised by wide concentric arc(s), extending out to large galactocentric distances with sharp outer edges. Recent observations of young massive star clusters in the prominent outer shell of NGC 474 suggest that such systems host extreme conditions of star formation. In this paper, we present a hydrodynamic simulation of a galaxy merger and its transformation into a shell galaxy. We analyse how the star formation activity evolves with time, location-wise within the system, and what are the physical conditions for star formation. During the interaction, an excess of dense gas appears, triggering a starburst, i.e. an enhanced star formation rate and a reduced depletion time. Star formation coincides with regions of high molecular gas fraction, such as the galactic nucleus, spiral arms, and occasionally the tidal debris during the early stages of the merger. Tidal interactions scatter stars into a stellar spheroid, while the gas cools down and reforms a disc. The morphological transformation after coalescence stabilises the gas and thus quenches star formation, without the need for feedback from an active galactic nucleus. This evolution shows similarities with a compaction scenario for compact quenched spheroids at high-redshift, yet without a long red nugget phase. Shells appear after coalescence, during the quenched phase, implying that they do not host the conditions necessary for in situ star formation. The results suggest that shell-forming mergers might be part of the process of turning blue late-type galaxies into red and dead early-types., Accepted for publication by MNRAS, 13 pages

The outer parts of the Milky Way's disc are significantly out of equilibrium. Using only distances and proper motions of stars from Gaia's Early Data Release 3, in the range |b, Comment: 15 pages, MNRAS accepted version. 7 minute video summary available at https://youtu.be/6zQvMivZONk

Background Approximately 90% of children and adolescents with type 1 diabetes in Sweden use continuous glucose monitoring (CGM), either as real-time CGM or intermittently scanned CGM to monitor their glucose levels. Time in target range (TIT) is an easily understandable metric for assessing glycemic control. Objective The aim of this study was to examine the relation between TIT and hemoglobin A1c (HbA1c). Subjects and methods Subjects were recruited from three diabetes care centers in Sweden. Glucose data were collected for 133 children and adolescents with type 1 diabetes through CGM using Diasend. Subjects with registration time over 80% were included in the analysis. HbA1c was collected from SWEDIABKIDS, the Swedish pediatric diabetes quality registry. TIT was defined as 3.9 to 7.8 mmol/L (70-140 mg/dL) and time in range (TIR) as 3.9 to 10 mmol/L (70-180 mg/dL). Results During the period of 60 days, 105 subjects provided complete data for analysis. Mean age was 12.2 (±3.3) years, mean HbA1c was 53.9 (±8.2) mmol/mol or 7.1% (±0.7%). Mean sensor glucose value was 8.6 (±1.3) mmol/L, mean coefficient of variation was 42.2% (±7.2%), mean TIT was 40.9% (±SD 12.2%), and mean TIR was 60.8% (±13.1%). There was a significant nonlinear relation between TIT during 60 days and HbA1c, R2 = 0.69. Conclusion This study suggests a nonlinear relation between time spent in glucose target range and HbA1c. The finding implies that time spent in TIT could be a useful metric in addition to HbA1c to assess glycemic control.