1,543 research outputs found

    Substantiation data for hypersonic cruise vehicle wing structure evaluation - Volume 1, sections 1-10

    Get PDF
    Trajectory, load, aerodynamic heating, materials, structural, and thermal analyses for hypersonic cruise vehicle wing

    Monitoring the Mauna Loa (Hawaii) eruption of November–December 2022 from space: Results from GOES-R, Sentinel-2 and Landsat-8/9 observations

    Get PDF
    Mauna Loa, one of the most actives volcanoes on Earth, is a shield volcano, located on the Island of Hawaii (USA). On 27 November 2022, after about 38 years of quiescence, a new eruptive activity took place at the Moku‘āweoweo caldera, continuing in the following days (i.e. until 10 December) from the fissure vents opening on the Northeast Rift Zone. In this work, we investigate the Mauna Loa November − December 2022 eruption from space, integrating the information from different satellite sensors. The analysis of short-wave infrared (SWIR) data, at 10 min temporal resolution, from the Advanced Baseline Imager (ABI), aboard the Geostationary Operational Environmental Satellites − R series (GOES-R), performed through the Normalised Hotspot Indices (NHI), indicates that the Mauna Loa eruption started on 27 November in between 23:10–23:20 LT (28 November at 09:10–09:20 UTC). The same analysis shows the increase of thermal activity and its progressive reduction from the early morning of 28 November, in agreement with the eruption migration from the summit caldera to the Northeast Rift Zone. By analysing the second phase of eruption through SWIR data from the Multispectral Instrument (MSI) and Operational Land Imager (OLI), respectively aboard Sentinel-2 and Landsat 8/9 satellites, we estimated a maximum lava flow length of 17 km. Moreover, we retrieved values of the volcanic radiative power (VRP) up to 65 GW, and a time-averaged discharge rate (TADR) of ∼1000 (±500) m3/s. These results show that SWIR observations, at different spatial and temporal resolution, may give an important contribution to the monitoring, mapping and characterisation of intense lava effusions

    CaRe-CNN: Cascading Refinement CNN for Myocardial Infarct Segmentation with Microvascular Obstructions

    Full text link
    Late gadolinium enhanced (LGE) magnetic resonance (MR) imaging is widely established to assess the viability of myocardial tissue of patients after acute myocardial infarction (MI). We propose the Cascading Refinement CNN (CaRe-CNN), which is a fully 3D, end-to-end trained, 3-stage CNN cascade that exploits the hierarchical structure of such labeled cardiac data. Throughout the three stages of the cascade, the label definition changes and CaRe-CNN learns to gradually refine its intermediate predictions accordingly. Furthermore, to obtain more consistent qualitative predictions, we propose a series of post-processing steps that take anatomical constraints into account. Our CaRe-CNN was submitted to the FIMH 2023 MYOSAIQ challenge, where it ranked second out of 18 participating teams. CaRe-CNN showed great improvements most notably when segmenting the difficult but clinically most relevant myocardial infarct tissue (MIT) as well as microvascular obstructions (MVO). When computing the average scores over all labels, our method obtained the best score in eight out of ten metrics. Thus, accurate cardiac segmentation after acute MI via our CaRe-CNN allows generating patient-specific models of the heart serving as an important step towards personalized medicine.Comment: Accepted at VISIGRAPP 2024, 12 page

    Holz von Vitis vinifera im Raster-Elektronenmikroskop

    Get PDF
    Charakteristische Gewebeteile und Zellelemente vom Holz des Weinstockes, Vitis vinifera L., wurden raster-elektronenmikroskopisch abgebildet. Dabei wurde auf die Ausbildung der lebenden, septierten Holzfasern besonderer Wert gelegt. Lebende, septierte Fasern treten auch im Bast auf (Bastfasern). Sie bilden alternierend mit dem Weichbast selbständige Gewebekomplexe und dienen wie die Holzfasern neben ihrer Stützfunktion vorwiegend der Stärkespeicherung. Die Bastfasern sind im Durchschnitt kürzer als die Holzfasern. Andere morphologische Unterschiede wurden nicht festgestellt.Bois de Vitis vinifera au microscope électronique à balayageLes parties caractéristiques du tissu et les éléments cellulaires du bois de vigne (Vitis vinifera L.) furent reproduits par microscopie électronique à balayage On s'est concentré particulièrement sur la formation des fibres vivantes et cloisonnées du bois. Des fibres vivantes et cloisonnées sont présentes également dans le phloème. Elles forment alternativement avec le liber mou un complexe de tissus indépendants et servent comme les fibres libriformes du xylème, en plus de leur rôle de support, surtout au stockage de l 'amidon. Les fibres de phloème sont en moyenne plus courtes que les fibres de xylème. D'autres différences morphologiques n'ont pas été constatées

    Generalized Hamiltonian structures for Ermakov systems

    Full text link
    We construct Poisson structures for Ermakov systems, using the Ermakov invariant as the Hamiltonian. Two classes of Poisson structures are obtained, one of them degenerate, in which case we derive the Casimir functions. In some situations, the existence of Casimir functions can give rise to superintegrable Ermakov systems. Finally, we characterize the cases where linearization of the equations of motion is possible

    MicroRNA expression is altered in an ovalbumin-induced asthma model and targeting miR-155 with antagomirs reveals cellular specificity

    Full text link
    ©2015 Plank et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source arecredited. MicroRNAs are post-transcriptional regulators of gene expression that are differentially regulated during development and in inflammatory diseases. A role for miRNAs in allergic asthma is emerging and further investigation is required to determine whether they may serve as potential therapeutic targets. We profiled miRNA expression in murine lungs from an ovalbumin-induced allergic airways disease model, and compared expression to animals receiving dexamethasone treatment and non-allergic controls. Our analysis identified 29 miRNAs that were significantly altered during allergic inflammation. Target prediction analysis revealed novel genes with altered expression in allergic airways disease and suggests synergistic miRNA regulation of target mRNAs. To assess the impacts of one induced miRNA on pathology, we targeted miR-155-5p using a specific antagomir. Antagomir administration successfully reduced miR-155-5p expression with high specificity, but failed to alter the disease phenotype. Interestingly, further investigation revealed that antagomir delivery has variable efficacy across different immune cell types, effectively targeting myeloid cell populations, but exhibiting poor uptake in lymphocytes. Our findings demonstrate that antagomir-based targeting of miRNA function in the lung is highly specific, but highlights cell-specificity as a key limitation to be considered for antagomir-based strategies as therapeutics
    • …
    corecore