Saxon State Ministry for Science and the Arts

The Progressive Stress Method (PSM) and the Multi-Level Stress Method (MLM) are two crucial methodologies employed in studying the aging and failure mechanism of insulating materials subjected to high voltage stress. Each method has its pros and cons. The presented study highlights the importance of understanding the relationship between the Progressive Stress Method and the Multi-Level Stress Method in assessing the aging and failure of insulating materials. The findings revealed that for the investigated insulation material and chosen testing conditions, the aging process of insulation is remarkably similar under both stress methods. However, it is observed that at Progressive Stress Method the measured breakdown voltage is higher than in comparison with MLM. In some cases, the application of PSM leads to a shorter testing time procedure. Under certain conditions, the results obtained by PSM might be converted into MLM lifetime values which allows an effective approximation of lifetime characteristics for applied insulation materials.

Abstract Remote sensing-based data on vegetation conditions provide important information for agriculture. In this study, the potential uses of the freely available High-Resolution Vegetation Phenology and Productivity Product (HR-VPP) are tested. This test examines the 2018 drought year in the state of Saxony, Germany, and the capabilities and limitations of the HR-VPP product in use with Integrated Administration and Control System (IACS) data. The results show that field and crop type-specific spatial (re)analyses of a drought are possible and that there is still great potential in this data analysis. Using the data in a new proposed VPP-based Farm-Level Temporal Comparison Indicator (VPP-FLTCI), it was not possible to tease out patterns in why farms applied for state drought aid in 2018 compared to other farms. In the future, even better and more detailed analyses based on the HR-VPP can be expected, as the data series with now a total of 5 years is still very short to generate sufficient references, especially in Central European agriculture, which is characterized by crop rotation.

Usutu virus (USUV) is a mosquito-borne flavivirus that is widely distributed in southern and central Europe. The zoonotic virus circulates primarily between birds and mosquitoes, can, however, in rare cases infect other mammals including humans. In the past, USUV has been repeatedly associated with mass mortalities in birds, primarily blackbirds and owls. Birds commonly succumb either due to the peracute nature of the infection or due to severe encephalitis. In Germany, USUV has spread rapidly since its first detection in 2010 in mosquitoes under the presence of susceptible host and vector species. Nonetheless, there is to date limited access to whole genome sequences resulting in the absence of in-depth phylogenetic and phylodynamic analyses. In this study, 118 wild and captive birds were sequenced using a nanopore sequencing platform with prior target enrichment via amplicons. Due to the high abundancy of Europe 3 and Africa 3 in Germany an ample quantity of associated whole genome sequences was generated and the most recent common ancestor could be determined for each lineage. The corresponding clock phylogeny revealed an introduction of USUV Europe 3 and Africa 3 into Germany three years prior to their first isolation in the avifauna in 2011 and 2014, respectively. Based on the clustering and temporal history of the lineages, evidence exists for the genetic evolution of USUV within Germany as well as new introductions thereof into the country.

This study was conducted to examine effects of ensiling, toasting or ensiling plus toasting in partial-crop field peas and faba beans harvested each with 375 g dry matter/kg (Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie (BBCH) scale 79 and 81, respectively) on gas production and post-ruminal crude protein (PRCP) concentration byin vitro incubation in ruminal fluid batch-cultures. The silages made from partial-crop field peas and faba beans (Rostock Model Silages) had a pH of 4.3 and 4.6, respectively, and were not typically lactic acid dominated. The silages remained stable after opening for 100 h (peas) and 168 h (faba beans). Toasting was simulated in a drying oven at 160 °C for 60 min. Post-incubation pH and gas accumulation profiles were little affected by treatment. Ensiling did not alter effective PRCP. Toasting and ensiling plus toasting increased effective PRCP up to 25 and 20%-points in peas and up to 35 and 11%-points in faba beans, respectively. Ensiling increased non-protein nitrogen and soluble protein concentration, whilst toasting decreased soluble protein. Significant correlations existed between protein fraction B3 (neutral detergent-insoluble protein) and effective PRCP (r≥0.84;P<0.05) and fraction C (acid detergent-insoluble protein) and effective PRCP (r≥0.79;P<0.05). Ensiling and toasting both decreased arginine and lysine levels. It was concluded that partial-crop peas and faba beans with BBCH 79 and 81, respectively, can provide readily available nutrients and high-quality fibre in the residual plant. However, preserving by ensiling required balance between the reduction of non-protein nitrogen and fermentability characteristics. Toasting reduced protein solubility and increased PRCP, but it was not clear if PRCP was usable for ruminants or was partially bound into Maillard polymers.

Forest liming is a management tool that has and continues to be used extensively across northern Europe to counteract acidification processes from anthropogenic sulfur and nitrogen (N) deposition. In this study, we quantified how liming affects soil organic carbon (SOC) stocks and attempt to disentangle the mechanisms responsible for the often-contrasting processes that regulate net soil carbon (C) fluxes. Using a paired-plot experimental design we compared SOC stocks in limed plots with adjacent unlimed control plots at 28 experimental sites to 60-cm soil depth in mature broadleaf and coniferous forests across Germany. Historical soil data from a subset of the paired experiment plots was analyzed to assess how SOC stocks in both control and limed plots had changed between 1990 and 2019. Overall, we found that forest floor C stocks have been accumulating over time, particularly in the control plots. Liming however largely offsets this organic layer buildup, which means that nutrients remain mobile and are not bound in soil organic matter complexes. Results from the paired plot analysis showed that forest floor C stocks were significantly lower in limed plots than the control ( 34 %, 8.4 ± 1.7 Mg C ha-1), but did not significantly affect SOC stocks in the mineral soil, when all sites are pooled together. In the forest floor layers, SOC stocks exhibited an exponential decrease with increasing pH, highlighting how lime-induced improvements in the biochemical environment stimulate organic matter (OM) decomposition. Nevertheless, for both forest floor and mineral soils, the magnitude and direction of the belowground C changes hinged directly on the inherent site characteristics, namely, forest type (conifer versus broadleaf), soil pH, soil texture and the soil SOC stocks. On the other hand, SOC stock decreases were often offset by other processes that fostered C accumulation, such as improved forest productivity or increased carbon stabilization, which correspondingly translated to an overall variable response by SOC stocks, particularly in the mineral soil. Lastly, we measured soil carbon dioxide (CO2) and soil methane (CH4) flux immediately after a re-liming event at three of the experimental sites. Here, we found that (1) liming doubles CH4 uptake in the long-term, (2) highlighted that soil organic matter mineralization processes respond quickly to liming, though the duration and size of the CO2 flush varied between sites, and (3) lime-derived CO2 contributed very little to total CO2 emissions over the measurement period.

This paper deals with medium frequency resonance effects in electrical machine windings, which can be excited by harmonic components of voltage source converters. The topic is getting more and more relevant with steadily increasing switching frequencies. For squirrel-cage induction machines with form-wound coils an algorithm is presented, which allows the prediction of first machine differential mode resonance frequencies already at design stage. Examples of the experimental model verification and interpretation of resonance frequencies complete the article.