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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

Contains fulltext : 285375.pdf (Publisher’s version ) (Open Access) This report offers a summary of the main findings of the international conference “Sustainable Rural Transformation in Africa”, held virtually from 26 May to 27 May 2020. The conference concluded the Interdisciplinary Fellow Group of the same name which operated between February and May 2020 at the Merian Center for Advanced Studies in Africa (MIASA), located at the University of Ghana. Bringing together researchers from different countries, as well as different disciplines, the conference created a space for discussions beyond topical silos. The conference focused on the impacts of large-scale agricultural investments on socio-economic structures and rural livelihoods—also taking into account a water-energy-food nexus approach; resource-based conflicts as well as mobility and urbanization. While common patterns of rural transformations could be identified, the debates concluded that there is a need to be more cognizant of the ambiguities of change and nuances that call into question simplistic assumptions. Sustainable Rural Transformation in Africa, 26 mei 2020

Objectives To assess inter observer variability of renal blood oxygenation level dependent MRI (BOLD MRI) using a new method of analysis called the concentric objects (CO) technique in comparison with the classical ROI (region of interest) based technique. Methods MR imaging (3 T) was performed before and after furosemide in 10 chronic kidney disease (CKD) patients (mean eGFR 43 ± 24 ml/min/1.73 m2) and 10 healthy volunteers (eGFR 101 ± 28 ml/min1.73 m2) and R2 maps were determined on four coronal slices. In the CO technique R2 values were based on a semi automatic procedure that divided each kidney in six equal layers whereas in the ROI technique all circles (ROIs) were placed manually in the cortex and medulla. The mean R2values as assessed by two independent investigators were compared. Results With the CO technique inter observer variability was 0.7–1.9 across all layers in non CKD versus 1.6–3.8 in CKD. With the ROI technique median variability for cortical and medullary R2 values was 3.6 and 6.8 in non CKD versus 4.7 and 12.5 in CKD; similar results were observed after furosemide. Conclusion The CO technique offers a new investigator independent highly reproducible alternative to the ROI based technique to estimate renal tissue oxygenation in CKD.

The goal of this study was to investigate the effect of sodium intake on renal tissue oxygenation in humans. To this purpose we measured renal hemodynamics renal sodium handling and renal oxygenation in normotensive (NT) and hypertensive (HT) subjects after 1 week of a high sodium and 1 week of a low sodium diet. Renal oxygenation was measured using blood oxygen level dependent magnetic resonance. Tissue oxygenation was determined by the measurement of R2 maps on 4 coronal slices covering both kidneys. The mean R2 values in the medulla and cortex were calculated with a low R2 indicating a high tissue oxygenation. Ten male NT (mean age: 26.5+/ 7.4 years) and 8 matched HT subjects (mean age: 28.8+/ 5.7 years) were studied. Cortical R2 was not different under the 2 conditions of salt intake. Medullary R2 was significantly lower under low sodium than high sodium in both NT and HT subjects (28.1+/ 0.8 versus 31.3+/ 0.6 s( 1); P

We have studied the interactive effects of salinity and light on Avicennia germinans mangrove seedlings in greenhouse and field experiments. We hypothesized that net photosynthesis, growth, and survivorship rates should increase more with an increase in light availability for plants growing at low salinity than for those growing at high salinity. This hypothesis was supported by our results for net photosynthesis and growth. Net daily photosynthesis did increase more with increasing light for low-salinity plants than for high-salinity plants. Stomatal conductance, leaf-level transpiration, and internal CO2 concentrations were lower at high than at low salinity.

An international forum exchange of knowledge of power systems impacts of wind power has been formed under the IEA Implementing Agreement on Wind Energy. The task 'Design and Operation of Power Systems with Large Amounts of Wind Power Production' will analyse existing case studies from different power systems. There is a multitude of studies made and ongoing related to cost of wind integration. However, the results are not easy to compare. This paper summarises the results from 10 countries and outlines the sudies made at European Wind Energy Association and the European system operators UCTE and ETSO. A more in-depth review of the studies is needed to draw conclusions on the range of integration costs for wind power. State-of-the art review process will seek for reasons behind the wide range of results for costs of wind integration-definitions for wind penetration, reserves and costs; different power system and load characteristics and operational rules; underlying assumptions on variability of wind etc.