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On February 6, 2023, southeastern Turkey was hit by two of the most devastating earthquakes in the instrumental period of the country, with Mw 7.8 and Mw 7.5, respectively. Both earthquakes caused massive damage in Turkey and Syria. In this study, we analyze the rupture processes of main- and aftershocks by combining different seismic source characterization techniques using teleseismic, regional, and local data. We perform finite source inversion and back projection-based analyses for the two main shocks and invert for probabilistic centroid moment tensor solutions of both main and aftershocks (M≥4). The first earthquake was bilateral and ruptured a seismic gap along the East Anatolian Fault, with rupture first propagating to the north-east for ~200 km, and in a latter phase propagating to the SSW, probably coming to a halt only on a branch extending into the Mediterranean Sea. The total length of the rupture likely exceeds 500 km. The second event ruptured the EW-oriented Sürgü-Misis Fault to the NW of the first event. It shows a highly concentrated rupture near the epicenter, Rupture directivity analyses for M≥5.3 earthquakes provide additional insights into dynamic source aspects. Preliminary moment tensor solutions of numerous aftershocks indicate a remarkable variability of rupturing mechanisms, suggesting stress changes and the activation of multiple faults in the vicinity of the main ruptures. With our work, we aim to shed light onto multiple aspects of the complex rupture evolution and hope to provide new insights towards a better understanding of the devastating 2023 Türkiye earthquake sequence., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The characterization of a seismic source is crucial to understand seismogenic processes. Simplified source models, e.g., a moment tensor, may not be suited for certain physical processes, such as landslides or complex earthquake ruptures. We propose here a double source model to reproduce landslide processes, with two opposite oriented forces representing the detachment and impact of a sliding mass. A double source model is also suited to characterize complex earthquake ruptures, as it allows modeling the failure of two patches along a single or on two different faults. The inversion for a double source is implemented in a Bayesian bootstrap-based probabilistic inversion scheme with uncertainty estimation for all parameters. In the case of landslides, the source is described by two independent single forces and earthquakes are described by two dependent double-couples. The double single-force model includes 16 free parameters and the double double-couple model includes 18. Here we show the results obtained in the analysis of three different landslides (Val Bondasca-Switzerland 2017, Anak Krakatoa-Indonesia 2018 and Uttarakhand-India 2021) and two complex earthquake ruptures (Alaska 2018, South Sandwich islands 2021). Our findings show that our approach can resolve the landslide geometry and slope orientation. For the case of earthquakes, we were able to resolve the focal mechanism along two faults, which were active during the Alaska 2018 earthquake, as well as the time delay and orientation of the South Sandwich doublet in 2021., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

MARIA S. MERIAN-Berichte

Bioactive compound design based on natural product (NP) structure may be limited because of partial coverage of NP-like chemical space and biological target space. These limitations can be overcome by combining NP-centered strategies with fragment-based compound design through combination of NP-derived fragments to afford structurally unprecedented “pseudo-natural products” (pseudo-NPs). The design, synthesis, and biological evaluation of a collection of indomorphan pseudo-NPs that combine biosynthetically unrelated indole- and morphan-alkaloid fragments are described. Indomorphane derivative Glupin was identified as a potent inhibitor of glucose uptake by selectively targeting and upregulating glucose transporters GLUT-1 and GLUT-3. Glupin suppresses glycolysis, reduces the levels of glucose-derived metabolites, and attenuates the growth of various cancer cell lines. Our findings underscore the importance of dual GLUT-1 and GLUT-3 inhibition to efficiently suppress tumor cell growth and the cellular rescue mechanism, which counteracts glucose scarcity.