The FIRE-IN project: Tsunami-risk related practitioner challenges and 3rd cycle overall results.

This article summarizes the methodology for the identification of practitioners' challenges, in the context of the H2020 funded project FIRE-IN (Fire and Rescue Innovation Network) activities. The project consisted of five thematic areas or "Thematic Working Groups", as they are called, i.e., Search and Rescue Emergency Response, Structure Fires, Landscape Fires Crisis Mitigation, Natural Hazard Mitigation and Chemical Biological Radiological Nuclear and Explosives, and three iterations, each one including the identification of capability challenges, the screening for solutions, that can potentially address these challenges, and the request for ideas regarding future innovations that will complement already existing ones and will assist in covering capability gaps. This article focuses on the natural hazard mitigation working group and tsunamis in the Mediterranean region as a case study for the 3rd and last iteration of the project. The scenario of a tsunami occurrence in the Mediterranean is the basis for the FIRE-IN 3rd cycle workshop, as an indicative example of a high impact - low probability event, which aims to identify practitioners' Future Common Capability Challenges in Europe. The current status of the tsunami hazard in Europe, national and international tsunami risk mitigation measures and procedures and operational experience from recent events are also discussed. Focus is provided on the natural hazard mitigation and tsunami related practitioners' challenges, while results from the FIRE-IN request for ideas process and the interaction between practitioners, researchers and industry are also discussed. The aim is to present practitioners' current and future capability challenges , one of the main outcomes of the FIRE-IN project, and to provide further guidelines to stakeholders of disaster management towards a safer Europe, mainly, through preparedness and adaptation for stronger and resilient societies.

Broken Global Symmetries and Defect Conformal Manifolds.

Just as exactly marginal operators allow one to deform a conformal field theory along the space of theories known as the conformal manifold, appropriate operators on conformal defects allow for deformations of the defects. When a defect breaks a global symmetry, there is a contact term in the conservation equation with an exactly marginal defect operator. The resulting defect conformal manifold is the symmetry breaking coset, and its Zamolodchikov metric is expressed as the two-point function of the exactly marginal operator. As the Riemann tensor on the conformal manifold can be expressed as an integrated four-point function of the marginal operators, we find an exact relation to the curvature of the coset space. We confirm this relation against previously obtained four-point functions for insertions into the 1/2 BPS Wilson loop in N=4 SYM and 3D N=6 theory and the 1/2 BPS surface operator of the 6D N=(2,0) theory.

Common and Uncommon Artifacts in T1 FLAIR SAG Sequences of MRI Brain.

OBJECTIVE: This study aims at identifying, classifying, and measuring the frequency the different artifacts that show up in the images of the Sagittal T1 Fluid Attenuated Inversion Recovery (FLAIR) sequence. MATERIALS AND METHODS: A total of 101 subjects underwent brain magnetic resonance imaging examination with the following sequences: Axial T1 FLAIR, Axial T2-weighted imaging, Diffusion Weighted Imaging, 2D Multiple Echo Recombined Gradient Echo, Sagittal T1 FLAIR, Coronal T2 Turbo Spin Echo, Spin Echo T1-weighted imaging, and 3D Fast Spoiled Gradient-echo. In these images, we observed the following categories of artifacts: (a) ghost artifacts, (b) aliasing behind the occipital bone, (c) aliasing inside the sphenoid cavity, (d) susceptibility artifacts, and (e) pulsation artifacts. In order to recognize and verify the artifacts, we used not only the Sagittal T1 FLAIR sequence, but also Sagittal reconstructions from the 3-dimensional Fast Spoiled Gradient-echo sequence and the other routine sequences. RESULTS: Aliasing artifacts and especially aliasing of nose are present in 41% of the cases. In 45% of these cases the uncommon aliasing artifacts, which took place into the brain parenchyma (sphenoid cavity, subarachnoid bay, or pituitary) originated from nose. In 33% of the subjects, ghost artifacts are presented, which stem from the nose, the orbits, or other pulsating structures (pulsation artifacts) or even from fat tissue. Moreover, susceptibility artifacts comprise 8% of all the artifacts. Finally, 19% of brains were presented without artifact. CONCLUSIONS: We suggest in addition to T1 FLAIR, the application of Sagittal SE or TSE sequences in magnetic resonance imaging examination of brain, trying to include the nose in the square of FOV.

Reduction of motion, truncation and flow artifacts using BLADE sequences in cervical spine MR imaging.

PURPOSE: To assess the efficacy of the BLADE technique (MR imaging with 'rotating blade-like k-space covering') to significantly reduce motion, truncation, flow and other artifacts in cervical spine compared to the conventional technique. MATERIALS AND METHODS: In eighty consecutive subjects, who had been routinely scanned for cervical spine examination, the following pairs of sequences were compared: a) T2 TSE SAG vs. T2 TSE SAG BLADE and b) T2 TIRM SAG vs. T2 TIRM SAG BLADE. A quantitative analysis was performed using the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measures. A qualitative analysis was also performed by two radiologists, who graded seven image characteristics on a 5-point scale (0: non-visualization; 1: poor; 2: average; 3: good; 4: excellent). The observers also evaluated the presence of image artifacts (motion, truncation, flow, indentation). RESULTS: In quantitative analysis, the CNR values of the CSF/SC between TIRM SAG and TIRM SAG BLADE were found to present statistically significant differences (p < 0.001). Regarding motion and truncation artifacts, the T2 TSE BLADE SAG was superior compared to the T2 TSE SAG, and the T2 TIRM BLADE SAG was superior compared to the T2 TIRM SAG. Regarding flow artifacts, T2 TIRM BLADE SAG eliminated more artifacts than T2 TIRM SAG. CONCLUSIONS: In cervical spine MRI, BLADE sequences appear to significantly reduce motion, truncation and flow artifacts and improve image quality. BLADE sequences are proposed to be used for uncooperative subjects. Nevertheless, more research needs to be done by testing additional specific pathologies.

Elimination of motion, pulsatile flow and cross-talk artifacts using blade sequences in lumbar spine MR imaging.

The purpose of this study is to evaluate the ability of T2 turbo spin echo (TSE) axial and sagittal BLADE sequences in reducing or even eliminating motion, pulsatile flow and cross-talk artifacts in lumbar spine MRI examinations. Forty four patients, who had routinely undergone a lumbar spine examination, participated in the study. The following pairs of sequences with and without BLADE were compared: a) T2 TSE Sagittal (SAG) in thirty two cases, and b) T2 TSE Axial (AX) also in thirty two cases. Both quantitative and qualitative analyses were performed based on measurements in different normal anatomical structures and examination of seven characteristics, respectively. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion, pulsatile flow and cross-talk artifacts was evaluated. Based on the results of the qualitative analysis for the different sequences and anatomical structures, the BLADE sequences were found to be significantly superior to the conventional ones in all the cases. The BLADE sequences eliminated the motion artifacts in all the cases. In our results, it was found that in the examined sequences (sagittal and axial) the differences between the BLADE and conventional sequences regarding the elimination of motion, pulsatile flow and cross-talk artifacts were statistically significant. In all the comparisons, the T2 TSE BLADE sequences were significantly superior to the corresponding conventional sequences regarding the classification of their image quality. In conclusion, this technique appears to be capable of potentially eliminating motion, pulsatile flow and cross-talk artifacts in lumbar spine MR images and producing high quality images in collaborative and non-collaborative patients.