Dekra (Germany)

With the integration of renewable energies the share of inverters in the grid increases and thus the inertia of the system is weakened. Grid-forming inverter coupled loads can contribute to system inertia. Handling of short circuits becomes a challenge. In contrast to synchronous generators, a grid-forming inverter coupled load decelerates during a fault, in dependence on the gridforming control, and can shorten the critical clearing time of the system. In this paper, we present a control scheme based on the virtual synchronous machine for a grid-forming inverter coupled load and propose different methods that change the frequency behavior during fault. Therefore, different current limitation methods and the adjustment of parameters during fault are analyzed. Good transient stability can be achieved with the help of the appropriate method and parameterization. Changing the inertia constant and adjusting the active power setpoint have proven to be particularly effective which is shown in MATLAB/Simulink simulations.

Emotion, Narration, and Ethics. The Ethical Relevance of Anticipatory Emotions in the Parables of the Gospel of Matthew.

Coronary heart disease is associated with high morbidity andmortality. Endothelial dysfunction in affected patients is linked to long-term atherosclerotic disease progression and cardiovascular event rates. The present paper reports on changes in the levels of endothelial progenitor cells (VEGFR2/CD133/CD34), essential for endothelial repair, and of endothelial microvesicles (CD31/annexin V) as indicators of endothelial lesion, in patients undergoing coronary bypass surgery with respect both to baseline levels and to counts in healthy subjects. In an observational descriptive study, 31 patients scheduled for coronary revascularization surgery were compared with those of 25 healthy controls. In a subsequent longitudinal study, patients undergoing surgery were monitored at5 timepoints up until 48h after surgery. Endothelial progenitor cell (VEGFR2/CD133/CD34) and endothelial microvesicle (CD31/annexin V) levels were quantified by flow cytometry. Baseline endothelial progenitor cell counts in coronary patients were significantly lower than those of healthy controls (p<0.001); however, after surgery, levels rose steadily over all 5timepoints to 48h with statistically significant differences (p<0.001) between intra-operative and 48h after surgery (T5). Endothelial microvesicle levels were significantly higher in coronary patients prior to surgery than in healthy controls (p<0.001), and despite declining at 48h remained significantly higher than those of controls (p<0.001). Coronary surgery has hada positive impact on the endothelium in the patients, prompting a decrease in signs of endothelial dysfunction and a considerable improvement in the endothelial repair mechanisms involved in angiogenesis, playing an important role in the inflammatory response and the remodelling process of ischemic myocardium in postoperative period.

Basically, collaboration and competition are historically well known aspects of economic behaviour. In Germany, they did come as associations, guilds, and collectives. These entities had been established to adjust imbalances between economical partners of different sizes.