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The modelling and simulation of nuclear reactors is increasingly carried out with open-source tools. To researchers, the most appealing benefits are the possibility to study and verify existing implementations and the freedom to add code for prototyping new concepts and models. Further, there is no direct dependency on a software manufacturer, which generally makes open-source codes a solid basis for collaboration. An important downside however is that the responsibility of controlling quality and reliability lies with the users. For actively developed code this is a continuous task and demands considerable resources which should be bundled. In the area of Computational Fluid Dynamics, a well-established open-source solution is OpenFOAM. Its development follows agile principles with a strong focus on maintainability and usability. This increases the demands on users to keep their setups functional. Since 2020, HZDR is creating an IT environment that supports the centralized and continuous maintenance of OpenFOAM code and simulation setups developed by members of the German nuclear safety research community. The project focuses on work relevant for the reactor cooling system and is referred to as OpenFOAM_RCS. Both, an addon to the OpenFOAM release from The OpenFOAM Foundation and a dedicated repository for simulation setups are supplied. The basis for the project is the web-based software development environment GitLab provided by the Helmholtz Federated IT Services (HIFIS), which allows for a high degree of automation with the help of continuous integration and deployment pipelines. Part of the project is the creation of a validation workflow Validation workflows should, among other things: (1) allow for continuous and automated checks of the setup input syntax; (2) frequently validate the simulation results by comparison against reference solutions; (3) be able to evaluate the impact of model substitutions on the overall “goodness” of results; (4) automatically create self-contained reports; (5) be executable on different environments, i.e. be portable and scalable; (5) allow for easy integration of new setups, i.e. be adaptable; (6) enable design point studies; (7) be comprehensible, ideally be self-documenting; (8) follow well-defined standards. All aforementioned requirements can be fulfilled with the popular and actively developed Python-based workflow management system Snakemake (Mölder et al., 2021), which was originally written for Bioinformatics workflows, but is far more versatile. In this work Snakemake is configured to embed all setups archived in OpenFOAM_RCS in a single workflow. Execution of simulation setups is controlled via so-called Snakefiles, which list inputs and outputs of a simulation, the required resources as well as the commands to run them. Within a top-level configuration file utilizing the easy to read markup language YAML, all setups to be incorporated in a workflow are listed. Once properly configured, users can run the workflow in four steps: (1) configuration, i.e. assembly of selected setups; (2) running the simulations; (3) post-processing the simulations; (4) creating HTML reports gathering all generated plots together with runtime statistics and provenance information. The third step can be executed on a workstation or a cluster. For the latter case, a top-level job organizes the workflow and automatically submits sub-jobs to the cluster. The proposed framework provides the opportunity to reduce cost and effort for CFD validation and verification. It also is of great help for complex model development such as multi-phase CFD where a large range of test cases and test conditions is mandatory to judge the performance of a given model choice. This work is carried out in the frame of a current research project funded by the German Federal Ministry for Environment, Nature Conservation, Nuclear Safety and Consumer Protection, project number 1501604.

Extrinsic apoptosis relies on TNF-family receptor activation by immune cells or receptor-activating biologics. Here, we monitored cell cycle progression at minutes resolution to relate apoptosis kinetics and cell-to-cell heterogeneities in death decisions to cell cycle phases. Interestingly, we found that cells in S phase delay TRAIL receptor-induced death in favour for mitosis, thereby passing on an apoptosis-primed state to their offspring. This translates into two distinct fates, apoptosis execution post mitosis or cell survival from inefficient apoptosis. Transmitotic resistance is linked to Mcl-1 upregulation from mid S phase onwards, which allows cells to pass through mitosis with activated caspase-8, and with cells escaping apoptosis after mitosis sustaining sublethal DNA damage. Antagonizing Mcl-1 by BH3-mimetics suppresses cell cycle-dependent delays in apoptosis, prevents apoptosis-resistant progression through mitosis and averts unwanted survival from apoptosis induction. Cell cycle progression therefore modulates signal transduction during extrinsic apoptosis, with Mcl-1 governing decision making between death, proliferation and survival from inefficient apoptosis induction. Cell cycle progression thus is a crucial process from which cell-to-cell heterogeneities in fates and treatment outcomes emerge in isogenic cell populations during extrinsic apoptosis signalling.

The use of digital technologies and social media has become an increasingly significant means for engagement in many fields, and that of cultural heritage is no exception. Specifically, Holocaust museums have long been committed to providing historical and educational content to their audiences, and to this end digital communication channels and social media in particular figure among the means employed. Despite this, relatively few research studies have investigated the potential of Holocaust museums' use of social media as new memory ecologies. This preliminary study investigates how three prominent Holocaust museums (Yad Vashem in Israel, the United States Holocaust Memorial Museum in Washington D.C., and the Auschwitz-Birkenau Memorial and Museum in Poland) use Twitter, Facebook and Instagram to enhance knowledge and understanding of historical and remembrance events among the general public. Using a mixed-methods approach, we analysed the museums' social media profiles on Facebook, Twitter and Instagram to investigate the topics and phrases that appear most often in the posted contents. Through latent semantic analyses, we determined the words most frequently used by the three museums themselves and within the three social media channels. Additionally, we employed topic modelling to determine underlying themes. This approach allowed us to identify possible similarities and differences between the museums' communication output and their social media channels. Moreover, to illustrate these potential similarities and differences, we also conducted 2-Mode network analyses. Our results show that the museums' use of each social media channel exhibits different types of topical foci. For example, Twitter posts specifically include terminology on "education", Facebook communication is more centred on the "camps" and the "Nazi" regime, while on Instagram the combination of "murdered" and "photo" can often be found. Furthermore, similarities were also found, namely that the topic of "Auschwitz" is omnipresent and that all museums appear to focus on the 1941-1945 timeframe.