ERC DarkMix : Large Eddy Observatory, Voitsumra Experiment 2019 (LOVE19)

The weak-wind Stable Boundary Layer (wwSBL) is poorly described by theory and breaks basic assumptions necessary for observations of turbulence. Understanding the wwSBL requires distributed observations capable of separating between submeso and turbulent scales. To this end, we present the Large Eddy Observatory, Voitsumra Experiment 2019 (LOVE19) which featured 1350m of fiber optic distributed sensing of air temperature and wind speed, as well as an experimental wind direction method, at scales as fine as 1s and 0.127m, in addition to a suite of point observations of turbulence and ground-based remote sensing. Additionally, flights with a fiber optic cable attached to a tethered balloon provide an unprecedented detailed view of the boundary layer structure with a resolution of 0.254m and 10s between 1-200m height. We anticipate that these data will be of interest to boundary layer researchers, but also may be applicable to other communities that study the exchange between the atmosphere and the surface. The novelty of the DTS data, supported by additional observations, hopefully allows the investigation of research questions that could not be adequately addressed before. A pdf detailing the experiment documentation (LOVE19_AE-Documentation.pdf) is provided to give an overview of the experiment and data in addition to a submitted (and hopefully future) Earth System Science Data (ESSD) manuscript. The AE-Documentation is volume 65 of the Arbeitsergebnisse, Universität Bayreuth, Mikrometeorologie publication series. All data are provided as self-describing netcdfs. Two example scripts (as python-based Jupyter Notebooks) are provided, reconstructing the example figures from the ESSD paper. The examples demonstrate the unique capabilities of the LOVE19 data for examining boundary layer processes: 1) FODS observations between 1m and ~200m height during a period of gravity waves propagating across the entire boundary layer and 2) tracking a near-surface, transient submeso structure that causes an intermittent burst of turbulence

Tumor Microvasculature in Lung Cancer and Diffusion-Weighted MRI: Preliminary Results

International audienceAngiogenesis is critically important in invasive tumor growth and metastasis. Many recent studies have focused on the microvasculature in tumor. The most often studied tumor tissues are from animals; rarely human tumors are selected. The analysis of microvasculature may provide useful information to understand the microperfusion of blood in tumor. One question is whether integration of histological analysis of the microvasculature in combination with diffusion-weighted MRI (DWI) gives coherent information about microperfusion. In this work, we aim to achieve the quantitative analysis of microvasculature in human tumor and attempt to compare the vessel features with blood perfusion in tumor. We applied a novel automatic procedure to extract blood vessels and reconstruct the 3D vessel structures in lung tumor based on serial histological tumor tissue slides. The digitized histological tissue slide is in 2D with fine resolution down to cellular level. The method was tested on a stack of 288 serial slides of a human lung tumor. We compared the vessel area fraction in two specific lung tumor regions with the perfusion-related parameter from IVIM (intravoxel incoherent motion) of DWI. High perfusion was observed in tumor sample with high vessel area fraction, hence our preliminary results indicate a possible relation between DWI and histological parameters, which shall be consolidated in future studies

Benefit of Contact Force Sensing Catheter Technology for Successful Left Atrial Anterior Line Formation: A Prospective Randomized Trial

Introduction. The value of contact force information for ablation of LA anterior line is unknown. In a prospective randomized clinical trial, we investigated if information on contact force during left atrial (LA) anterior line ablation reduces total radiofrequency time and results in higher rates of bidirectional line block in patients undergoing pulmonary vein isolation (PVI) plus substrate modification. Methods. We included patients with indication for pulmonary vein isolation (PVI) and additional substrate modification. For LA anterior line ablation, patients were randomized to contact force information visible (n=35) or blinded (n=37). Patients received contrast enhanced cardiac magnetic resonance imaging (cMRI) before and 3-6 months after ablation to visualize the LA anterior line. Primary endpoint was radiofrequency time to achieve bidirectional line block. Secondary endpoints were completeness of the LA anterior line on cMRI, distribution of contact force, procedural data, adverse events, and 12 months success rate. Results. In 72 patients (64±9 years, 68% male), bidirectional LA anterior line block was achieved in 70 (97%) patients. Radiofrequency time to bidirectional block did not differ significantly across groups (contact force information visible 23±18min versus contact force information blinded 21±15min, p=0.50). The LA anterior line was discernable on cMRI in 40 patients (82%) without significant differences across randomization groups (p=0.46). No difference in applied contact force was found depending on cMRI line visibility. Twelve-month success and adverse event rates were comparable across groups. Conclusion. Information on contact force does not significantly improve the ablation of LA anterior lines. Clinical Trial Registration. The trial was registered at http://www.clinicaltrials.gov by identifier: NCT02217657