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We investigated several layered perovskite derivatives of the family AnBnO3n+2, such as LaTiO3.41, CaNbO3.41 and SrNbO3.41, which can be considered as a stacking of blocks consisting of 5 perovskite layers. Electric transport across these layers takes place via intrinsic tunnelling. Mesa devices with a cross-sectional area of 50 to 200 µm2 and a height between 30 and 500 nm were fabricated by electron-beam lithography and ion-beam etching. Both dc I-V characteristics and pulsed current injection have shown switching between different resistive states in these materials. The resistive states have long-term stability, which makes them interesting for memory applications. The transport experiments suggest that switching and resistive memory are controlled by trapping and release of charge carriers. Furthermore, photoelectron and NEXAFS spectroscopy of cleaved LaTiO3.41 surfaces have been performed. The results are compared to recent correlated band theory (LDA+U) calculations.
BACKGROUND:
Coronavirus disease 2019 (COVID-19) can cause acute respiratory distress syndrome (ARDS).
OBJECTIVE:
This single centre cross-section study aimed to grade the severity of pneumonia by bed-side lung ultrasound (LUS).
METHODS:
A scoring system discriminates 5 levels of lung opacities: A-lines (0 points),≥3 B-line (1 point), coalescent B-lines (2 points), marked pleural disruptions (3 points), consolidations (4 points). LUS (convex 1–5 MHz probe) was performed at 6 defined regions for each hemithorax either in supine or prone position. A lung aeration score (LAS, maximum 4 points) was allocated for each patient by calculating the arithmetic mean of the examined lung areas. Score levels were correlated with ventilation parameters and laboratory markers.
RESULTS:
LAS of 20 patients with ARDS reached from 2.58 to 3.83 and was highest in the lateral right lobe (Mean 3.67). Ferritin levels (Mean 1885μg/l; r = 0.467; p = 0.051) showed moderate correlation in spearman roh calculation. PaCO2 level (Mean 46.75 mmHg; r = 0.632; p = 0.005) correlated significantly with LAS, while duration of ventilation, Horovitz index, CRP, LDH and IL-6 did not.
CONCUSIONS:
The proposed LAS describes severity of lung opacities in COVID-19 patients and correlates with CO2 retention in patients with ARDS.
The water balance of the Rivers Spree, Schwarze Elster and Lusatian Neisse is profoundly disturbed due to large-scale open-cast lignite mining activities and water management. Together with continental climate conditions this affects
water resources and water users in the region. Driven by scenarios of the regional climate model STAR which assume increasing temperature and decreasing precipitation, two hydrological models, the Soil and Water Integrated Model
SWIM and the catchment model EGMO simulate declining natural discharges in the region. Thus, decreasing managed discharges are simulated with the long term water management model WBalMo. The refinement of the simulation time step of WBalMo from months to weeks improves the consideration of climate variability and is also associated with higher simulated managed discharges in
early summer. Management scenarios in terms of a reduced outlet capacity of a mining lake reservoir result in higher releases from other reservoirs and slightly
reduced summer discharges in downstream river sections.
Auswirkungen von Unsicherheiten in Klimaszenarien auf die regionale Wassermengenbewirtschaftung
(2014)
In den Lausitzer Flusseinzugsgebieten von Schwarzer Elster, Dahme, Spree und Lausitzer Neiße zeigen sich durch Braunkohlebergbau und vielfältige Bewirtschaftungseinflüsse deutliche Unterschiede zwischen natürlichem Abflussgeschehen und bewirtschafteten Abflüssen. Die möglichen Auswirkungen klimatischer Änderungen werden durch eine Klimawandelimpaktstudie mit dem statistischen Regionalen Klimamodell STAR (3 Klimaszenarien), den hydrologischen Modellen SWIM und EGMO
sowie dem Langfristbewirtschaftungsmodell WBalMo untersucht. Durch niedrigere natürliche Abflüsse und den angenommenen Rückgang der Sümpfungswassermengen aus dem Braunkohlebergbau werden mit WBalMo abnehmende bewirtschaftete Abflüsse simuliert. Unsicherheiten bestehen dabei auf Grund der genutzten Klimaszenarien und hydrologischen Modelle, sowie hinsichtlich der Annahmen
zur zukünftigen wirtschaftlichen Entwicklung (u.a. Braunkohleförderung und –verstromung).
A slow-fast trait continuum at the whole community level in relation to land-use intensification
(2024)
AbstractOrganismal functional strategies form a continuum from slow- to fast-growing organisms, in response to common drivers such as resource availability and disturbance. However, whether there is synchronisation of these strategies at the entire community level is unclear. Here, we combine trait data for 2800 above- and belowground taxa from 14 trophic guilds spanning a disturbance and resource availability gradient in German grasslands. The results indicate that most guilds consistently respond to these drivers through both direct and trophically mediated effects, resulting in a ‘slow-fast’ axis at the level of the entire community. Using 15 indicators of carbon and nutrient fluxes, biomass production and decomposition, we also show that fast trait communities are associated with faster rates of ecosystem functioning. These findings demonstrate that ‘slow’ and ‘fast’ strategies can be manifested at the level of whole communities, opening new avenues of ecosystem-level functional classification.