Fernerkundung zum Schutz des Regenwaldes

Die Zerstoerung der Regenwaelder hat ein noch nie dagewesenes Ausmass erreicht. Weltraumgestuetzten Aufklaerungssystemen kommt bei der Erfassung dieser grossflaechigen Umweltzerstoerung eine herausragende Rolle zu. Spezialkameras auf der russischen Raumstation MIR, die in 400 km Hoehe alle 90 Minuten die Erde umkreist, liefern Aufnahmen von den Regenwaeldern mit einer bisher nicht gesehenen Qualitaet. Mit einer Bodenaufloesung von ca. 7,5 Metern erlauben die Farbaufnahmen eine detailgenaue Analyse der Vorgaenge in den weitraeumigen, unzugaenglichen Regenwaldgebieten

Hybrid material additive manufacturing: interlocking interfaces for fused filament fabrication on laser powder bed fusion substrates

The fabrication of polymer–metal hybrids in an additive process makes it possible to further improve the geometrical and material adaption in a multi-material design. In this work, PLA is fabricated through a fused filament fabrication process on AlSi10Mg structures manufactured by laser powder bed fusion. The mechanical connection is realised by form fit, for which different geometries are examined through tensile tests. Deep penetration of the PLA into the metallic structures is achieved by optimisation of the process parameters. The penetration depth is assessed through the use of micro-computed tomography. Finally, the interplay of mechanisms leading to a firm connection is discussed

Functional aplasia of the contralateral A1 segment influences clinical outcome in patients with occlusion of the distal internal carotid artery

Background: The importance of an A1 aplasia remains unclear in stroke patients. In this work, we analyze the impact of an A1 aplasia contralateral to an acute occlusion of the distal internal carotid artery (ICA) on clinical outcomes. Methods: We conducted a retrospective study of consecutive stroke patients treated with mechanical thrombectomy at 12 tertiary care centers between January 2015 and February 2021 due to an occlusion of the distal ICA. Functional A1 aplasia was defined as the absence of A1 or hypoplastic A1 (>50% reduction to the contralateral site). Functional independence was measured by the modified Rankin Scale (mRS ≤ 2). Results: In total, 81 out of 1068 (8%) patients had functional A1 aplasia contralateral to distal ICA occlusion. Patients with functional contralateral A1 aplasia were more severely affected on admission (median NIHSS 18, IQR 15–23 vs. 17, IQR 13–21; aOR: 0.672, 95% CI: 0.448–1.007, p = 0.054) and post-interventional ischemic damage was larger (median ASPECTS 5, IQR 1–7, vs. 6, IQR 3–8; aOR: 1.817, 95% CI: 1.184–2.789, p = 0.006). Infarction occurred more often within the ipsilateral ACA territory (20/76, 26% vs. 110/961, 11%; aOR: 2.482, 95% CI: 1.389–4.437, p = 0.002) and both ACA territories (8/76, 11% vs. 5/961, 1%; aOR: 17.968, 95% CI: 4.979–64.847, p ≤ 0.001). Functional contralateral A1 aplasia was associated with a lower rate of functional independence at discharge (6/81, 8% vs. 194/965, 20%; aOR: 2.579, 95% CI: 1.086–6.122, p = 0.032) and after 90 days (5/55, 9% vs. 170/723, 24%; aOR: 2.664, 95% CI: 1.031–6.883, p = 0.043). Conclusions: A functional A1 aplasia contralateral to a distal ICA occlusion is associated with a poorer clinical outcome

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements