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Mixed-phase clouds are common in Arctic cyclones, but their representation in global atmospheric models is still challenging. The aim of the study is to evaluate and improve the ratio of ice and liquid water within mixed-phase clouds simulated by two general circulation models (GCM): ARPEGE (operational at Météo-France) and LMDZ (the atmospheric component of the IPSL-CM Earth System Model). For that evaluation, we consider ERA5 reanalysis for the overall dynamics and for the cloud representation, DARDAR satellite products which provide the ice water content (IWC) as well as categorization masks along CloudSat-CALIPSO tracks. This work focuses on an Arctic cyclone that occurred in May 2019 near Svalbard and has been sampled several times by CloudSat-CALIPSO.Compared to satellite observations, LMDZ simulations provide quite realistic IWC while ARPEGE underestimates this quantity. However, by comparing liquid and ice occurrences between models and observations, both GCMs clearly miss occurrences of liquid phase at temperature lower than -30°C but they all overestimate the liquid occurrence in the whole negative temperature range between 0°C and -30°C.In order to improve such liquid and ice occurrences, different liquid/ice partition functions are tested in the two models. In particular, different shapes and extensions to lower temperatures are considered. This helps to improve the occurrence of liquid water at the lowest temperatures but does not correct the overestimation between 0°C and -30°C. As temperature does not discriminate liquid-ice partition properly, different other predictors are tested and distance from the cloud top appears to be the most relevant., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Frequency and voltage stability is a challenge as power systems move towards a more renewable future. This study focuses on the power system of Suðuroy, Faroe Islands, which is in the transition towards 100% renewables. The impact of three events on the frequency and voltage responses has been simulated based on 2020, 2023, 2026 and 2030 and with different settings using a measurement validated model. These results show that additional ancillary services, provided by e.g., batteries and synchronous condensers, are required to keep the stability level at the same level as today. The isolated power system in Suðuroy (~10% of total annual demand) will be connected to the main grid (~90% of total annual demand) in the future (2026 according to the RoadMap), and thus the system has also been studied with this interconnection. According to the simulation results, the main grid contributes significantly to the power system stability in Suðuroy when the systems are interconnected. The impact of how the main grid has been represented is also analysed by conducting simulations using a detailed model of the main grid or approximated models. The results show that the suggested approximated models do not show a sufficiently accurate response compared to the detailed model; especially when batteries in the main grid are contributing with active power regulation. Therefore, new approximated models of power systems with high shares of inverter-based technologies should be developed with this consideration. Finally, the contribution from wind turbine inertia emulation is analysed and shows that the system frequency nadir can be improved with the emulated inertia feature switched on.

Fragestellung: Verschiedene Organisationen haben in den letzten 10 Jahren ihre Definitionen des periprothetischen Infektes (PPI) bei Blut-und Synovialproben publiziert mit einigen Alleinstellungsmerkmalen, vor allem aber deutlichen Überschneidungen in den richtungsweisenden Tests. Die Einführung [zum vollständigen Text gelangen Sie über die oben angegebene URL]

Fragestellung: Frakturen der Metatarsalia (MT) gehören zu den häufigsten Brüchen des Fuß- und Sprunggelenkes. Allerdings fehlen valide Daten zur Verteilung dieser Frakturen. Das Ziel dieser Arbeit war die Verteilung von Metatarsalfrakturen sowie mögliche Einflussfaktoren in [zum vollständigen Text gelangen Sie über die oben angegebene URL]

Hintergrund: Die Überproduktion reaktiver Sauerstoffspezies wird als oxidativer Stress bezeichnet. Dieser tritt bei mehreren Netzhauterkrankungen auf, einschließlich dem Glaukom, der AMD oder Gefäßverschlüssen. Wasserstoffperoxid (H2O2) kann in vitro verwendet werden, um oxidativen[zum vollständigen Text gelangen Sie über die oben angegebene URL], 183. Versammlung des Vereins Rheinisch-Westfälischer Augenärzte